Neural stem/progenitor cell properties of glial cells in the adult mouse auditory nerve - Lang, Hainan; Xing, Yazhi; Brown, Lashardai N.; Samuvel, Devadoss J.; Panganiban, Clarisse H.; Havens, Luke T.; Balasubramanian, Sundaravadivel; Wegner, Michael; Krug, Edward L.; Barth, Jeremy L. (Scientific Reports, 2015)
The auditory nerve is the primary conveyor of hearing information from sensory hair cells to the brain. It has been believed that loss of the auditory nerve is irreversible in the adult mammalian ear, resulting in sensorineural hearing loss. We examined the regenerative potential of the auditory nerve in a mouse model of auditory neuropathy. Following neuronal degeneration, quiescent glial cells converted to an activated state showing a decrease in nuclear chromatin condensation, altered histone deacetylase expression and up-regulation of numerous genes associated with neurogenesis or development. Neurosphere formation assays showed that adult auditory nerves contain neural stem/progenitor cells (NSPs) that were within a Sox2-positive glial population. Production of neurospheres from auditory nerve cells was stimulated by acute neuronal injury and hypoxic conditioning. These results demonstrate that a subset of glial cells in the adult auditory nerve exhibit several characteristics of NSPs and are therefore potential targets for promoting auditory nerve regeneration.
EVALuna2:4976

Neuroblastoma RAS Viral Oncogene Homolog (NRAS) Is a Novel Prognostic Marker and Contributes to Sorafenib Resistance in Hepatocellular Carcinoma - Dietrich, Peter; Gaza, Anne; Wormser, Laura; Fritz, Valerie; Hellerbrand, Claus; Boßerhoff, Anja Katrin (Neoplasia, 2019)
Inhibition of the RAS-RAF-ERK-pathway using sorafenib as a first-line and regorafenib as a second-line treatment approach is the only effective therapeutic strategy for advanced hepatocellular carcinoma (HCC). Recent studies suggest that wild-type KRAS and HRAS isoforms could majorly contribute to HCC progression and sorafenib resistance. In contrast, the role of neuroblastoma RAS viral oncogene homolog (NRAS) in HCC remained elusive. In this study, wild-type NRAS was found to be overexpressed in HCC cell lines, preclinical HCC models, and human HCC tissues. Moreover, NRAS overexpression correlated with poor survival and proliferation in vivo. However, siRNA-pool-mediated NRAS knockdown showed only slight effects on HCC proliferation, clonogenicity, and AKT activity. We determined that KRAS upregulation served as a functional compensatory mechanism in the absence of NRAS, which was overcome by combined inhibition of NRAS and KRAS in HCC cells. Furthermore, NRAS expression was elevated in sorafenib-resistant compared to nonresistant HCC cells, and NRAS knockdown enhanced sorafenib efficacy in resistant cells. In summary, NRAS appears to be a prognostic marker in HCC and contributes to sorafenib resistance. Regarding potential therapeutic strategies, NRAS inhibition in HCC should be combined with KRAS inhibition to prevent KRAS-mediated rescue effects.
CRIS-Team WoS Importer:2019-03-20

Neuromuscular endplate pathology in recessive desminopathies: Lessons from man and mice - Durmus, Hacer; Ayhan, Ozgecan; Cirak, Sebahattin; Deymeer, Feza; Parman, Yesim; Franke, Andre; Eiber, Nane; Chevessier, Frederic; Schlötzer-Schrehardt, Ursula; Clemen, Christoph S.; Hashemolhosseini, Said; Schröder, Rolf; et al. (Neurology, 2016)
To assess the clinical, genetic, and myopathologic findings in 2 cousins with lack of desmin, the response to salbutamol in one patient, and the neuromuscular endplate pathology in a knock-in mouse model for recessive desminopathy.We performed clinical investigations in the patients, genetic studies for linkage mapping, exome sequencing, and qPCR for transcript quantification, assessment of efficacy of (3-month oral) salbutamol administration by muscle strength assessment, 6-minute walking test (6MWT), and forced vital capacity, analysis of neuromuscular endplate pathology in a homozygous R349P desmin knock-in mouse by immunofluorescence staining of the hind limb muscles, and quantitative 3D morphometry and expression studies of acetylcholine receptor genes by quantitative PCR.Both patients had infantile-onset weakness and fatigability, facial weakness with bilateral ptosis and ophthalmoparesis, generalized muscle weakness, and a decremental response over 10% on repetitive nerve stimulation. Salbutamol improved 6MWT and subjective motor function in the treated patient. Genetic analysis revealed previously unreported novel homozygous truncating desmin mutation c.345dupC leading to protein truncation and consequent fast degradation of the mutant mRNA. In the recessive desminopathy mouse with low expression of the mutant desmin protein, we demonstrated fragmented motor endplates with increased surface areas, volumes, and fluorescence intensities in conjunction with increased ? and ? acetylcholine receptor subunit expression in oxidative soleus muscle.The patients were desmin-null and had myopathy, cardiomyopathy, and a congenital myasthenic syndrome. The data from man and mouse demonstrate that the complete lack as well as the markedly decreased expression of mutant R349P desmin impair the structural and functional integrity of neuromuscular endplates.
EVALuna2:4994

Neuropeptide Y restores non-receptor-mediated vasoconstrictive action in superior mesenteric arteries in portal hypertension - Hartl, Johannes; Dietrich, Peter; Moleda, Lukas; Mueller-Schilling, Martina; Wiest, Reiner (Liver International, 2015)
Vascular hyporeactivity to vasoconstrictors contributes to splanchnic arterial vasodilatation and hemodynamic dysregulation in portal hypertension. Neuropeptide Y (NPY), a sympathetic cotransmitter, has been shown to improve adrenergic vascular contractility in portal hypertensive rats and markedly attenuate hyperdynamic circulation. To further characterize the NPY-effects in portal hypertension, we investigated its role for non-receptor-mediated vasoconstriction in the superior mesenteric artery (SMA) of portal vein ligated (PVL) and sham-operated rats.Ex vivo SMA perfusion of PVL and sham rats was used to analyse the effects of NPY on pressure response to non-receptor-mediated vasoconstriction. Dose-response curves to KCl (30-300 mM) were used to bypass G protein-coupled receptor mechanisms. Potential involvement of the cyclooxygenase-pathway was tested by non-selective cyclooxygenase-inhibition using indomethacin.KCl-induced vascular contractility but not vascular sensitivity was significantly attenuated in PVL rats as compared with sham rats. Administration of NPY resulted in an augmentation of KCl-evoked vascular sensitivity being not different between study groups. However, KCl-induced vascular contractility was markedly more enhanced in PVL rats, thus, vascular response was no more significantly different between PVL and sham rats after addition of NPY. Administration of indomethacin abolished the NPY-induced enhancement of vasoconstriction.Receptor-independent vascular contractility is impaired in mesenteric arteries in portal hypertension. NPY improves non-receptor mediated mesenteric vasoconstriction more effective in portal hypertension than in healthy conditions correcting splanchnic vascular hyporesponsiveness. This beneficial vasoactive action of NPY adds to its well known more pronounced effects on adrenergic vasoconstriction in portal hypertension making it a promising therapeutic agent in portal hypertension.
EVALuna2:4721

New insights into the clinical and molecular spectrum of the novel CYFIP2-related neurodevelopmental disorder and impairment of the WRC-mediated actin dynamics - Begemann, Anaïs; Sticht, Heinrich; Begtrup, Amber; Vitobello, Antonio; Faivre, Laurence; Banka, Siddharth; Alhaddad, Bader; Asadollahi, Reza; Becker, Jessica; Bierhals, Tatjana; Brown, Kathleen E.; Bruel, Ange Line; et al. (Genetics in Medicine, 2020)
Purpose: A few de novo missense variants in the cytoplasmic FMRP-interacting protein 2 (CYFIP2) gene have recently been described as a novel cause of severe intellectual disability, seizures, and hypotonia in 18 individuals, with p.Arg87 substitutions in the majority. Methods: We assembled data from 19 newly identified and all 18 previously published individuals with CYFIP2 variants. By structural modeling and investigation of WAVE-regulatory complex (WRC)-mediated actin polymerization in six patient fibroblast lines we assessed the impact of CYFIP2 variants on the WRC. Results: Sixteen of 19 individuals harbor two previously described and 11 novel (likely) disease-associated missense variants. We report p.Asp724 as second mutational hotspot (4/19 cases). Genotype–phenotype correlation confirms a consistently severe phenotype in p.Arg87 patients but a more variable phenotype in p.Asp724 and other substitutions. Three individuals with milder phenotypes carry putative loss-of-function variants, which remain of unclear pathogenicity. Structural modeling predicted missense variants to disturb interactions within the WRC or impair CYFIP2 stability. Consistent with its role in WRC-mediated actin polymerization we substantiate aberrant regulation of the actin cytoskeleton in patient fibroblasts. Conclusion: Our study expands the clinical and molecular spectrum of CYFIP2-related neurodevelopmental disorder and provides evidence for aberrant WRC-mediated actin dynamics as contributing cellular pathomechanism.
CRIS-Team Scopus Importer:2020-11-13
Keywords: CYFIP2; epilepsy; intellectual disability; WASF; WAVE-regulatory complex (WRC)

Next Generation Sequencing (NGS): What Can Be Sequenced? - Boßerhoff, Anja Katrin; Kappelmann-Fenzl, Melanie (Next Generation Sequencing and Data Analysis, 2021)

Nfat/calcineurin signaling promotes oligodendrocyte differentiation and myelination by transcription factor network tuning. - Weider, Matthias; Starost, Laura Julia; Groll, Katharina; Küspert, Melanie; Sock, Elisabeth; Wedel, Miriam; Fröb, Franziska; Schmitt, Christian; Baroti, Tina; Hartwig, Anna; Hillgärtner, Simone; Piefke, Sandra; et al. (Nature Communications, 2018)
Oligodendrocytes produce myelin for rapid transmission and saltatory conduction of action potentials in the vertebrate central nervous system. Activation of the myelination program requires several transcription factors including Sox10, Olig2, and Nkx2.2. Functional interactions among them are poorly understood and important components of the regulatory network are still unknown. Here, we identify Nfat proteins as Sox10 targets and regulators of oligodendroglial differentiation in rodents and humans. Overall levels and nuclear fraction increase during differentiation. Inhibition of Nfat activity impedes oligodendrocyte differentiation in vitro and in vivo. On a molecular level, Nfat proteins cooperate with Sox10 to relieve reciprocal repression of Olig2 and Nkx2.2 as precondition for oligodendroglial differentiation and myelination. As Nfat activity depends on calcium-dependent activation of calcineurin signaling, regulatory network and oligodendroglial differentiation become sensitive to calcium signals. NFAT proteins are also detected in human oligodendrocytes, downregulated in active multiple sclerosis lesions and thus likely relevant in demyelinating disease.
UnivIS-Import:2018-09-11:Pub.2018.med.IB.LPCIPDBI.nfatca

Nkx2.2 is a direct target gene of Sox10 in oligodendroglia - Weider, Matthias; Schmitt, Christian; Hillgärtner, Simone; Wegner, Michael (2017)
EVALuna2:33484

Nociception in the Glycine Receptor Deficient Mutant Mouse Spastic - Grömer, Teja Wolfgang; Triller, Antoine; Zeilhofer, Hanns Ulrich; Becker, Kristina; Eulenburg, Volker; Becker, Cord-Michael (Frontiers in Molecular Neuroscience, 2022)
Glycine receptors (GlyRs) are the primary mediators of fast inhibitory transmission in the mammalian spinal cord, where they modulate sensory and motor signaling. Mutations in GlyR genes as well as some other genes underlie the hereditary disorder hyperekplexia, characterized by episodic muscle stiffness and exaggerated startle responses. Here, we have investigated pain-related behavior and GlyR expression in the spinal cord of the GlyR deficient mutant mouse spastic (spa). In spastic mice, the GlyR number is reduced due to a β subunit gene (Glrb) mutation resulting in aberrant splicing of GlyRβ transcripts. Via direct physical interaction with the GlyR anchoring protein gephyrin, this subunit is crucially involved in the postsynaptic clustering of heteromeric GlyRs. We show that the mutation differentially affects aspects of the pain-related behavior of homozygous Glrbspa/Glrbspa mice. While response latencies to noxious heat were unchanged, chemically induced pain-related behavior revealed a reduction of the licking time and an increase in flinching in spastic homozygotes during both phases of the formalin test. Mechanically induced nocifensive behavior was reduced in spastic mice, although hind paw inflammation (by zymosan) resulted in allodynia comparable to wild-type mice. Immunohistochemical staining of the spinal cord revealed a massive reduction of dotted GlyRα subunit immunoreactivity in both ventral and dorsal horns, suggesting a reduction of clustered receptors at synaptic sites. Transcripts for all GlyRα subunit variants, however, were not reduced throughout the dorsal horn of spastic mice. These findings suggest that the loss of functional GlyRβ subunits and hence synaptically localized GlyRs compromises sensory processing differentially, depending on stimulus modality.
CRIS-Team Scopus Importer:2022-06-03
Keywords: glycine receptor; glycinergic inhibition; nociception; pain; spastic; synaptic clustering

Non-alcoholic fatty liver disease, obesity and the metabolic syndrome - Dietrich, Peter; Hellerbrand, Claus (Best Practice & Research in Clinical Gastroenterology, 2014)
Nonalcoholic fatty liver disease (NAFLD) is now recognized as the most common cause of chronic liver disease worldwide. Its prevalence has increased to more than 30% of adults in developed countries and its incidence is still rising. The majority of patients with NAFLD have simple steatosis but in up to one third of patients, NAFLD progresses to its more severe form nonalcoholic steatohepatitis (NASH). NASH is characterized by liver inflammation and injury thereby determining the risk to develop liver fibrosis and cancer. NAFLD is considered the hepatic manifestation of the metabolic syndrome. However, the liver is not only a passive target but affects the pathogenesis of the metabolic syndrome and its complications. Conversely, pathophysiological changes in other organs such as in the adipose tissue, the intestinal barrier or the immune system have been identified as triggers and promoters of NAFLD progression. This article details the pathogenesis of NAFLD along with the current state of its diagnosis and treatment.
EVALuna2:4701

Noncanonical NF-?B activation by the oncoprotein Tio occurs through a nonconserved TRAF3-binding motif - de Jong, Sarah Jill; Albrecht, Jens-Christian; Giehler, Fabian; Kieser, Arnd; Sticht, Heinrich; Biesinger, Brigitte (Science Signaling, 2013)
Members of the nuclear factor ?B (NF-?B) family of transcription factors regulate many cellular functions. Activation of NF-?B signaling is commonly classified as occurring through canonical or noncanonical pathways. Most NF-?B-inducing stimuli, including the viral oncoprotein Tio, lead to a concerted activation of both NF-?B pathways; however, extensive crosstalk at multiple levels between these signaling cascades restricts the ability to discriminate between the canonical and the noncanonical effects. We showed that noncanonical NF-?B activation by Tio depends on a distinct sequence motif that directly recruits tumor necrosis factor receptor-associated factor 3 (TRAF3). Through its TRAF3-binding motif, Tio triggered a ubiquitin-independent depletion of TRAF3 from the cytosol, which prevented TRAF3 from inhibiting signaling through the noncanonical NF-?B cascade. Furthermore, the Tio-TRAF3 interaction did not affect components of the canonical NF-?B signaling pathway or the expression of target genes; thus, Tio induced noncanonical NF-?B independently of crosstalk with the canonical pathway. Together, these data identify a distinct molecular mechanism of noncanonical NF-?B activation that should enable studies into the particular functions of this pathway.
EVALuna2:8187

Novel method of isolating nuclei of human oligodendrocyte precursor cells reveals substantial developmental changes in gene expression and H3K27ac histone modification - Kozlenkov, Alexey; Vadukapuram, Ramu; Zhou, Ping; Fam, Peter; Wegner, Michael; Dracheva, Stella (Glia, 2023)
Oligodendrocyte precursor cells (OPCs) generate differentiated mature oligodendrocytes (MOs) during development. In adult brain, OPCs replenish MOs in adaptive plasticity, neurodegenerative disorders, and after trauma. The ability of OPCs to differentiate to MOs decreases with age and is compromised in disease. Here we explored the cell specific and age-dependent differences in gene expression and H3K27ac histone mark in these two cell types. H3K27ac is indicative of active promoters and enhancers. We developed a novel flow-cytometry-based approach to isolate OPC and MO nuclei from human postmortem brain and profiled gene expression and H3K27ac in adult and infant OPCs and MOs genome-wide. In adult brain, we detected extensive H3K27ac differences between the two cell types with high concordance between gene expression and epigenetic changes. Notably, the expression of genes that distinguish MOs from OPCs appears to be under a strong regulatory control by the H3K27ac modification in MOs but not in OPCs. Comparison of gene expression and H3K27ac between infants and adults uncovered numerous developmental changes in each cell type, which were linked to several biological processes, including cell proliferation and glutamate signaling. A striking example was a subset of histone genes that were highly active in infant samples but fully lost activity in adult brain. Our findings demonstrate a considerable rearrangement of the H3K27ac landscape that occurs during the differentiation of OPCs to MOs and during postnatal development of these cell types, which aligned with changes in gene expression. The uncovered regulatory changes justify further in-depth epigenetic studies of OPCs and MOs in development and disease.
CRIS-Team Scopus Importer:2023-09-22
Keywords: development; epigenetics; OPC

Novel mutation in CNTNAP1 results in congenital hypomyelinating neuropathy. - Mehta, Paulomi; Küspert, Melanie; Bale, Tejus; Brownstein, Catherine A.; Towne, Meghan C.; De Girolami, Umberto; Shi, Jiahai; Beggs, Alan H.; Darras, Basil T.; Wegner, Michael; Piao, Xianhua; Agrawal, Pankaj B. (Muscle & Nerve, 2017)
UnivIS-Import:2018-09-05:Pub.2017.med.IB.LPCIPDBI.novelm
Keywords: CNTNAP1; congenital neuropathy; exome sequencing; hypomyelination; missense mutation; nerve conduction

NR2F1 shapes mitochondria in the mouse brain, providing new insights into Bosch-Boonstra-Schaaf optic atrophy syndrome. - Bonzano, Sara; Dallorto, Eleonora; Molineris, Ivan; Michelon, Filippo; Crisci, Isabella; Gambarotta, Giovanna; Neri, Francesco; Oliviero, Salvatore; Beckervordersandforth, Ruth; Lie, Dieter Chichung; Peretto, Paolo; Bovetti, Serena; et al. (Disease Models & Mechanisms, 2023)
The nuclear receptor NR2F1 acts as a strong transcriptional regulator in embryonic and postnatal neural cells. In humans, mutations in the NR2F1 gene cause Bosch-Boonstra-Schaaf optic atrophy syndrome (BBSOAS), a rare neurodevelopmental disorder characterized by multiple clinical features including vision impairment, intellectual disability and autistic traits. In this study, we identified, by genome-wide and in silico analyses, a set of nuclear-encoded mitochondrial genes as potential genomic targets under direct NR2F1 transcriptional control in neurons. By combining mouse genetic, neuroanatomical and imaging approaches, we demonstrated that conditional NR2F1 loss of function within the adult mouse hippocampal neurogenic niche results in a reduced mitochondrial mass associated with mitochondrial fragmentation and downregulation of key mitochondrial proteins in newborn neurons, the genesis, survival and functional integration of which are impaired. Importantly, we also found dysregulation of several nuclear-encoded mitochondrial genes and downregulation of key mitochondrial proteins in the brain of Nr2f1-heterozygous mice, a validated BBSOAS model. Our data point to an active role for NR2F1 in the mitochondrial gene expression regulatory network in neurons and support the involvement of mitochondrial dysfunction in BBSOAS pathogenesis.
EVALuna2:537078

N-Terminus to Arginine Side-Chain Cyclization of Linear Peptidic Neuropeptide y Y4Receptor Ligands Results in Picomolar Binding Constants - Konieczny, Adam; Conrad, Marcus; Ertl, Fabian J.; Gleixner, Jakob; Gattor, Albert O.; Grätz, Lukas; Schmidt, Maximilian F.; Neu, Eduard; Horn, Anselm; Wifling, David; Gmeiner, Peter; Clark, Timothy; et al. (Journal of Medicinal Chemistry, 2021)
The family of neuropeptide Y (NPY) receptors comprises four subtypes (Y1R, Y2R, Y4R, Y5R), which are addressed by at least three endogenous peptides, i.e., NPY, peptide YY, and pancreatic polypeptide (PP), the latter showing a preference for Y4R. A series of cyclic oligopeptidic Y4R ligands were prepared by applying a novel approach, i.e., N-terminus to arginine side-chain cyclization. Most peptides acted as Y4R partial agonists, showing up to 60-fold higher Y4R affinity compared to the linear precursor peptides. Two cyclic hexapeptides (18, 24) showed higher Y4R potency (Ca2+ aequorin assay) and, with pKi values >10, also higher Y4R affinity compared to human pancreatic polypeptide (hPP). Compounds such as 18 and 24, exhibiting considerably lower molecular weight and considerably more pronounced Y4R selectivity than PP and previously described dimeric peptidic ligands with high Y4R affinity, represent promising leads for the preparation of labeled tool compounds and might support the development of drug-like Y4R ligands.
CRIS-Team Scopus Importer:2021-12-03

Nuclear AREG affects a low-proliferative phenotype and contributes to drug resistance of melanoma - Seefried, Felix; Haller, Lucia; Fukuda, Shinji; Thongmao, Aranya; Schneider, Nadja; Utikal, Jochen; Higashiyama, Shigeki; Boßerhoff, Anja Katrin; Kuphal, Silke (International Journal of Cancer, 2022)
AMPHIREGULIN (AREG) is a multifaceted molecule, which acts not only as an extracellular ligand for EGF receptor (EGFR), but also as an intracellular signaling molecule. It remains elusive, however, whether AREG has a tumor suppressive or oncogenic role in melanoma. Here, we found that several melanoma cell lines express AREG, but the expression does not correlate with that of EGFR. Recombinant AREG and the neutralizing antibody experiments showed that intracellular AREG plays an important role in melanoma, implying a divergent function of AREG in addition to the role as a ligand for EGFR. Further investigation of this mechanism revealed that particularly nuclear-localized AREG regulates IGF-1R, P21 (Cip1/Waf1), TP53 and JARID1B protein accumulation in the nucleus. Furthermore, manipulation of nuclear AREG levels has influence on heterochromatin condensation (HP1beta, SETDB1) and trimethylation of histones H3K9 and H3K4. As these molecules correspond to previously identified markers for slow-cycling drug resistant cells, we speculate that nuclear AREG predisposes cells to resistance to therapy. According to the hypothesis, we detected the accumulation of AREG in the nucleus of SK-Mel-28-VR, which was cultured under Vemurafenib (VR) selection pressure, and this correlates with JARID1B expression. Here, knockdown of AREG makes the previously resistant cells more sensitive to VR treatment, resulting in inhibited proliferation. Taken together, we suggest that nuclear AREG affects a slow-cycling phenotype and increases resistance to VR, raising a possibility that AREG might be a potential therapeutic target for resistance in melanoma.
CRIS-Team WoS Importer:2022-09-16

Nuclear Egress Complexes of HCMV and Other Herpesviruses: Solving the Puzzle of Sequence Coevolution, Conserved Structures and Subfamily-Spanning Binding Properties - Marschall, Manfred; Häge, Sigrun; Conrad, Marcus; Alkhashrom, Sewar; Kicuntod, Jintawee; Schweininger, Johannes; Kriegel, Mark; Loesing, Josephine; Tillmanns, Julia; Neipel, Frank; Eichler, Jutta; Muller, Yves; et al. (Viruses, 2020)
Herpesviruses uniquely express two essential nuclear egress-regulating proteins forming a heterodimeric nuclear egress complex (core NEC). These core NECs serve as hexameric lattice-structured platforms for capsid docking and recruit viral and cellular NEC-associated factors that jointly exert nuclear lamina as well as membrane-rearranging functions (multicomponent NEC). The regulation of nuclear egress has been profoundly analyzed for murine and human cytomegaloviruses (CMVs) on a mechanistic basis, followed by the description of core NEC crystal structures, first for HCMV, then HSV-1, PRV and EBV. Interestingly, the highly conserved structural domains of these proteins stand in contrast to a very limited sequence conservation of the key amino acids within core NEC-binding interfaces. Even more surprising, although a high functional consistency was found when regarding the basic role of NECs in nuclear egress, a clear specification was identified regarding the limited, subfamily-spanning binding properties of core NEC pairs and NEC multicomponent proteins. This review summarizes the evolving picture of the relationship between sequence coevolution, structural conservation and properties of NEC interaction, comparing HCMV to alpha-, beta- and gamma-herpesviruses. Since NECs represent substantially important elements of herpesviral replication that are considered as drug-accessible targets, their putative translational use for antiviral strategies is discussed.
CRIS-Team WoS Importer:2020-08-07

Nuclear import of isoforms of the cytomegalovirus kinase pUL97 is mediated by differential activity of NLS1 and NLS2 both acting through classical importin-? binding - Webel, Rike; Solbak, Sara M. O.; Held, Christian; Milbradt, Jens; Groß, Andrea; Eichler, Jutta; Wittenberg, Thomas; Jardin, Christophe; Sticht, Heinrich; Fossen, Torgils; Marschall, Manfred (Journal of General Virology, 2012)
The multifunctional protein kinase pUL97 of human cytomegalovirus (HCMV) strongly determines the efficiency of virus replication. Previously, the existence of two pUL97 isoforms that arise from alternative translational initiation and show a predominant nuclear localization was described. Two bipartite nuclear localization sequences, NLS1 and NLS2, were identified in the N terminus of the large isoform, whilst the small isoform exclusively contained NLS2. The current study found the following: (i) pUL97 nuclear localization in HCMV-infected primary fibroblasts showed accumulations in virus replication centres and other nuclear sections; (ii) in a quantitative evaluation system for NLS activity, the large isoform showed higher efficiency of nuclear translocation than the small isoform; (iii) NLS1 was mapped to aa 6-35 and NLS2 to aa 190-213; (iv) using surface plasmon resonance spectroscopy, the binding of both NLS1 and NLS2 to human importin-? was demonstrated, stressing the importance of individual arginine residues in the bipartite consensus motifs; (v) nuclear magnetic resonance spectroscopy of pUL97 peptides confirmed an earlier statement about the functional requirement of NLS1 embedding into an intact ?-helical structure; and (vi) a bioinformatics investigation of the solvent-accessible surface suggested a high accessibility of NLS1 and an isoform-specific, variable accessibility of NLS2 for interaction with importin-?. Thus, the nucleocytoplasmic transport mechanism of the isoforms appeared to be differentially regulated, and this may have consequences for isoform-dependent functions of pUL97 during virus replication.
EVALuna2:8160

Null mutation in PGAP1 impairing Gpi-anchor maturation in patients with intellectual disability and encephalopathy - Murakami, Yoshiko; Tawamie, Hasan; Maeda, Yusuke; Büttner, Christian; Buchert, Rebecca; Radwan, Farah; Schaffer, Susann; Sticht, Heinrich; Aigner, Michael; Reis, André; Kinoshita, Taroh; Abou Jamra, Rami (PLoS Genetics, 2014)
Many eukaryotic cell-surface proteins are anchored to the membrane via glycosylphosphatidylinositol (GPI). There are at least 26 genes involved in biosynthesis and remodeling of GPI anchors. Hypomorphic coding mutations in seven of these genes have been reported to cause decreased expression of GPI anchored proteins (GPI-APs) on the cell surface and to cause autosomal-recessive forms of intellectual disability (ARID). We performed homozygosity mapping and exome sequencing in a family with encephalopathy and non-specific ARID and identified a homozygous 3 bp deletion (p.Leu197del) in the GPI remodeling gene PGAP1. PGAP1 was not described in association with a human phenotype before. PGAP1 is a deacylase that removes an acyl-chain from the inositol of GPI anchors in the endoplasmic reticulum immediately after attachment of GPI to proteins. In silico prediction and molecular modeling strongly suggested a pathogenic effect of the identified deletion. The expression levels of GPI-APs on B lymphoblastoid cells derived from an affected person were normal. However, when those cells were incubated with phosphatidylinositol-specific phospholipase C (PI-PLC), GPI-APs were cleaved and released from B lymphoblastoid cells from healthy individuals whereas GPI-APs on the cells from the affected person were totally resistant. Transfection with wild type PGAP1 cDNA restored the PI-PLC sensitivity. These results indicate that GPI-APs were expressed with abnormal GPI structure due to a null mutation in the remodeling gene PGAP1. Our results add PGAP1 to the growing list of GPI abnormalities and indicate that not only the cell surface expression levels of GPI-APs but also the fine structure of GPI-anchors is important for the normal neurological development.
EVALuna2:9210

Olfactory ensheathing cells abutting the embryonic olfactory bulb express Frzb, whose deletion disrupts olfactory axon targeting - Rich, Constance A.; Perera, Surangi N.; Andratschke, Jacqueline; Stolt, Claus; Buehler, Dennis P.; Southard-Smith, E. Michelle; Wegner, Michael; Britsch, Stefan; Baker, Clare V. H. (Glia, 2018)
We and others previously showed that in mouse embryos lacking the transcription factor Sox10, olfactory ensheathing cell (OEC) differentiation is disrupted, resulting in defective olfactory axon targeting and fewer gonadotropin-releasing hormone (GnRH) neurons entering the embryonic forebrain. The underlying mechanisms are unclear. Here, we report that OECs in the olfactory nerve layer express Frzb-encoding a secreted Wnt inhibitor with roles in axon targeting and basement membrane breakdown-from embryonic day (E)12.5, when GnRH neurons first enter the forebrain, until E16.5, the latest stage examined. The highest levels of Frzb expression are seen in OECs in the inner olfactory nerve layer, abutting the embryonic olfactory bulb. We find that Sox10 is required for Frzb expression in OECs, suggesting that loss of Frzb could explain the olfactory axon targeting and/or GnRH neuron migration defects seen in Sox10-null mice. At E16.5, Frzb-null embryos show significant reductions in both the volume of the olfactory nerve layer expressing the maturation marker Omp and the number of Omp-positive olfactory receptor neurons in the olfactory epithelium. As Omp upregulation correlates with synapse formation, this suggests that Frzb deletion indeed disrupts olfactory axon targeting. In contrast, GnRH neuron entry into the forebrain is not significantly affected. Hence, loss of Frzb may contribute to the olfactory axon targeting phenotype, but not the GnRH neuron phenotype, of Sox10-null mice. Overall, our results suggest that Frzb secreted from OECs in the olfactory nerve layer is important for olfactory axon targeting.
EVALuna2:35737

Olfactory ensheathing glia are required for embryonic olfactory axon targeting and the migration of gonadotropin-releasing hormone neurons - Barraud, Perrine; St John, James A.; Stolt, Claus; Wegner, Michael; Baker, Clare V. H. (Biology Open, 2013)
Kallmann's syndrome is caused by the failure of olfactory axons and gonadotropin-releasing hormone (GnRH) neurons to enter the embryonic forebrain, resulting in anosmia and sterility. Sox10 mutations have been associated with Kallmann's syndrome phenotypes, but their effect on olfactory system development is unknown. We recently showed that Sox10 is expressed by neural crest-derived olfactory ensheathing cells (OECs). Here, we demonstrate that in homozygous Sox10(lacZ/lacZ) mouse embryos, OEC differentiation is disrupted; olfactory axons accumulate in the ventromedial olfactory nerve layer and fewer olfactory receptor neurons express the maturation marker OMP (most likely owing to the failure of axonal targeting). Furthermore, GnRH neurons clump together in the periphery and a smaller proportion enters the forebrain. Our data suggest that human Sox10 mutations cause Kallmann's syndrome by disrupting the differentiation of OECs, which promote embryonic olfactory axon targeting and hence olfactory receptor neuron maturation, and GnRH neuron migration to the forebrain.
EVALuna2:4943

Olig2 regulates Sox10 expression in oligodendrocyte precursors through an evolutionary conserved distal enhancer. - Küspert, Melanie; Hammer, Alexander; Bösl, Michael; Wegner, Michael (Nucleic Acids Research, 2011)
The HMG-domain transcription factor Sox10 is expressed throughout oligodendrocyte development and is an important component of the transcriptional regulatory network in these myelin-forming CNS glia. Of the known Sox10 regulatory regions, only the evolutionary conserved U2 enhancer in the distal 5′-flank of the Sox10 gene exhibits oligodendroglial activity. We found that U2 was active in oligodendrocyte precursors, but not in mature oligodendrocytes. U2 activity also did not mediate the initial Sox10 induction after specification arguing that Sox10 expression during oligodendroglial development depends on the activity of multiple regulatory regions. The oligodendroglial bHLH transcription factor Olig2, but not the closely related Olig1 efficiently activated the U2 enhancer. Olig2 bound U2 directly at several sites including a highly conserved one in the U2 core. Inactivation of this site abolished the oligodendroglial activity of U2 in vivo. In contrast to Olig2, the homeodomain transcription factor Nkx6.2 repressed U2 activity. Repression may involve recruitment of Nkx6.2 to U2 and inactivation of Olig2 and other activators by protein-protein interactions. Considering the selective expression of Nkx6.2 at the time of specification and in differentiated oligodendrocytes, Nkx6.2 may be involved in limiting U2 activity to the precursor stage during oligodendrocyte development. The Author(s) 2010. Published by Oxford University Press.2010This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/ licenses/by-nc/2.5), which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. © The Author(s) 2010.
UnivIS-Import:2015-04-14:Pub.2011.med.IB.LPCIPDBI.olig2r

Oligodendroglial-specific transcriptional factor SOX10 is ubiquitously expressed in human gliomas. - Wegner, Michael; Stolt, Claus; et al. (Journal of Neuro-Oncology, 2006)
UnivIS-Import:2015-03-09:Pub.2006.med.IB.LPCIPDBI.oligod

Oligodendroglial α-synucleinopathy-driven neuroinflammation in multiple system atrophy - Hoffmann, Alana; Ettle, Benjamin; Battis, Kristina; Reiprich, Simone; Schlachetzki, Johannes; Masliah, Eliezer; Wegner, Michael; Kuhlmann, Tanja; Riemenschneider, Markus J.; Winkler, Jürgen (Brain Pathology, 2018)
Neuroinflammation and oligodendroglial cytoplasmic α-synuclein (α-syn) inclusions (GCIs) are important neuropathological characteristics of multiple system atrophy (MSA). GCIs are known to interfere with oligodendroglial maturation and consequently result in myelin loss. The neuroinflammatory phenotype in the context of MSA, however, remains poorly understood. Here, we demonstrate MSA-associated neuroinflammation being restricted to myeloid cells and tightly linked to oligodendroglial α-syncleinopathy. In human putaminal post-mortem tissue of MSA patients, neuroinflammation was observed in white matter regions only. This locally restricted neuroinflammation coincided with elevated numbers of α-syn inclusions, while gray matter with less α-synucleinopathy remained unaffected. In order to analyze the temporal pattern of neuroinflammation, a transgenic mouse model overexpressing human α-syn under the control of an oligodendrocyte-specific myelin basic protein (MBP) promoter (MBP29-hα-syn mice) was assessed in a pre-symptomatic and symptomatic disease stage. Strikingly, we detected an increased neuroinflammation in regions with a high α-syn load, the corpus callosum and the striatum, of MBP29-hα-syn mice, already at a pre-symptomatic stage. Furthermore, this inflammatory response was restricted to myeloid cells being highly proliferative and showing an activated, phagocytic phenotype. In contrast, severe astrogliosis was observed only in gray matter regions of MSA patients as well as MBP29-hα-syn mice. To further characterize the influence of oligodendrocytes on initiation of the myeloid immune response, we performed RNA sequencing analysis of α-syn overexpressing primary oligodendrocytes. A distinct gene expression profile including upregulation of cytokines important for myeloid cell attraction and proliferation was detected in α-syn overexpressing oligodendrocytes. Additionally, microdissected tissue of MBP29-hα-syn mice exhibited a similar cellular gene expression profile in white matter regions even pre-symptomatically. Collectively, these results imply an early crosstalk between neuroinflammation and oligodendrocytes containing α-syn inclusions leading to an immune response locally restricted to white matter regions in MSA.
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Oligodendrogliogenic and neurogenic adult subependymal zone neural stem cells constitute distinct lineages and exhibit differential responsiveness to Wnt signalling - Ortega, Felipe; Gascon, Sergio; Masserdotti, Giacomo; Deshpande, Aditi; Simon, Christiane; Fischer, Judith; Dimou, Leda; Lie, Dieter Chichung; Schroeder, Timm; Berninger, Benedikt (Nature Cell Biology, 2013)
The adult mouse subependymal zone (SEZ) harbours adult neural stem cells (aNSCs) that give rise to neuronal and oligodendroglial progeny. However it is not known whether the same aNSC can give rise to neuronal and oligodendroglial progeny or whether these distinct progenies constitute entirely separate lineages. Continuous live imaging and single-cell tracking of aNSCs and their progeny isolated from the mouse SEZ revealed that aNSCs exclusively generate oligodendroglia or neurons, but never both within a single lineage. Moreover, activation of canonical Wnt signalling selectively stimulated proliferation within the oligodendrogliogenic lineage, resulting in a massive increase in oligodendrogliogenesis without changing lineage choice or proliferation within neurogenic clones. In vivo activation or inhibition of canonical Wnt signalling respectively increased or decreased the number of Olig2 and PDGFR- ? positive cells, suggesting that this pathway contributes to the fine tuning of oligodendrogliogenesis in the adult SEZ.
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Oligomer-prone E57K-mutant alpha-synuclein exacerbates integration deficit of adult hippocampal newborn neurons in transgenic mice - Regensburger, Martin; Schreglmann, Sebastian R.; Stoll, Svenja; Rockenstein, Edward; Loskarn, Sandra; Xiang, Wei; Masliah, Eliezer; Winner, Beate (Brain Structure & Function, 2017)
In the adult mammalian hippocampus, new neurons are constantly added to the dentate gyrus. Adult neurogenesis is impaired in several neurodegenerative mouse models including ?-synuclein (a-syn) transgenic mice. Among different a-syn species, a-syn oligomers were reported to be the most toxic species for neurons. Here, we studied the impact of wild-type vs. oligomer-prone a-syn on neurogenesis. We compared the wild-type a-syn transgenic mouse model (Thy1-WTS) to its equivalent transgenic for oligomer-prone E57K-mutant a-syn (Thy1-E57K). Transgenic a-syn was highly expressed within the hippocampus of both models, but was not present within adult neural stem cells and neuroblasts. Proliferation and survival of newly generated neurons were unchanged in both transgenic models. Thy1-WTS showed a minor integration deficit regarding mushroom spine density of newborn neurons, whereas Thy1-E57K exhibited a severe reduction of all spines. We conclude that cell-extrinsic a-syn impairs mushroom spine formation of adult newborn neurons and that oligomer-prone a-syn exacerbates this integration deficit. Moreover, our data suggest that a-syn reduces the survival of newborn neurons by a cell-intrinsic mechanism during the early neuroblast development. The finding of increased spine pathology in Thy1-E57K is a new pathogenic function of oligomeric a-syn and precedes overt neurodegeneration. Thus, it may constitute a readout for therapeutic approaches.
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Oncogenic insult to the brain: Sox proteins rise to the occasion. - Wüst, Hannah; Wegner, Michael (TRANSLATIONAL CANCER RESEARCH, 2018)
UnivIS-Import:2018-09-05:Pub.2018.med.IB.LPCIPDBI.oncoge

Onset of Spinal Cord Astrocyte Precursor Emigration from the Ventricular Zone Involves the Zeb1 Transcription Factor - Ohayon, David; Garces, Alain; Joly, Willy; Soukkarieh, Chadi; Takagi, Tsuyoshi; Sabourin, Jean-Charles; Agius, Eric; Darling, Douglas S.; Barbara, Pascal De Santa; Higashi, Yujiro; Stolt, Claus; Hugnot, Jean-Philippe; et al. (Cell Reports, 2016)
During spinal cord development, astrocyte precursors arise from neuroepithelial progenitors, delaminate from the ventricular zone, and migrate toward their final locations where they differentiate. Although the mechanisms underlying their early specification and late differentiation are being deciphered, less is known about the temporal control of their migration. Here, we show that the epithelial-mesenchymal transition regulator Zeb1 is expressed in glial precursors and report that loss of Zeb1 function specifically delays the onset of astrocyte precursor delamination from the ventricular zone, correlating with transient deregulation of the adhesion protein Cadherin-1. Consequently, astrocyte precursor invasion into the Zeb1(-/-) mutant white matter is delayed, and induction of their differentiation is postponed. These findings illustrate how fine regulation of adhesive properties influences the onset of neural precursor migration and further support the notion that duration of exposure of migrating astrocyte precursors to environmental cues and/or their correct positioning influence the timing of their differentiation.
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Oral intake of xanthohumol attenuates lipoteichoic acid-induced inflammatory response in human PBMCs - Jung, Finn; Staltner, Raphaela; Tahir, Ammar; Baumann, Anja; Burger, Katharina; Halilbasic, Emina; Hellerbrand, Claus; Bergheim, Ina (European Journal of Nutrition, 2022)
Purpose The aim of the study was to determine if xanthohumol, a prenylated chalcone found in Hop (Humulus lupulus), has anti-inflammatory effects in healthy humans if applied in low doses achievable through dietary intake. Methods In a placebo-controlled single-blinded cross-over design study, 14 healthy young men and women either consumed a beverage containing 0.125 mg xanthohumol or a placebo. Peripheral blood mononuclear cells (PBMCs) were isolated before and 1 h after the intake of the beverages. Subsequently, PBMCs were stimulated with or without lipoteichoic acid (LTA) for 24 and 48 h. Concentrations of interleukin-1 beta (IL-1 beta), interleukin-6 (IL-6) and soluble cluster of differentiation (sCD14) protein were determined in cell culture supernatant. Furthermore, hTLR2 transfected HEK293 cells were stimulated with LTA in the presence or absence of xanthohumol and sCD14. Results The stimulation of PBMCs with LTA for 24 and 48 h resulted in a significant induction of IL-1 beta, IL-6, and sCD14 protein release in PBMCs of both, fasted subjects and subjects after the ingestion of the placebo. In contrast, after ingesting xanthohumol, LTA-dependent induction of IL-1 beta, IL-6, and sCD14 protein release from PBMCs was not significantly higher than in unstimulated cells after 48 h. In hTLR2 transfected HEK293 cells xanthohumol significantly suppressed the LTA-dependent activation of cells, an effect attenuated when cells were co-incubated with sCD14. Conclusion The results of our study suggest that an ingestion of low doses of xanthohumol can suppress the LTA-dependent stimulation of PBMCs through mechanisms involving the interaction of CD14 with TLR2. Study registered at ClinicalTrials.gov (NCT04847193, 22.03.2022).
CRIS-Team WoS Importer:2022-07-29

Orchestration of Neuronal Differentiation and Progenitor Pool Expansion in the Developing Cortex by SoxC Genes - Chen, Chao; Lee, Garrett A.; Pourmorady, Ariel; Sock, Elisabeth; Donoghue, Maria J. (The Journal of Neuroscience, 2015)
As the cerebral cortex forms, specialized molecular cascades direct the expansion of progenitor pools, the differentiation of neurons, or the maturation of discrete neuronal subtypes, together ensuring that the correct amounts and classes of neurons are generated. In several neural systems, the SoxC transcriptional regulators, particularly Sox11 and Sox4, have been characterized as functioning exclusively and redundantly in promoting neuronal differentiation. Using the mouse cerebral cortex as a model, Sox11 and Sox4 were examined in the formation of the most complex part of the mammalian brain. Anticipated prodifferentiation roles were observed. Distinct expression patterns and mutant phenotypes, however, reveal that Sox11 and Sox4 are not redundant in the cortex, but rather act in overlapping and discrete populations of neurons. In particular, Sox11 acts in early-born neurons; binding to its partner protein, Neurogenin1, leads to selective targeting and transactivation of a downstream gene, NeuroD1. In addition to neuronal expression, Sox4 was unexpectedly expressed in intermediate progenitor cells, the transit amplifying cell of the cerebral cortex. Sox4 mutant analyses reveal a requirement for Sox4 in IPC specification and maintenance. In intermediate progenitors, Sox4 partners with the proneural gene Neurogenin2 to activate Tbrain2 and then with Tbrain2 to maintain this cell fate. This work reveals an intricately structured molecular architecture for SoxC molecules, with Sox11 acting in a select set of cortical neurons and Sox4 playing an unanticipated role in designating secondary progenitors.
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Organogenesis relies on Sox4, Sox11, and Sox12 for survival of neural and mesenchymal progenitor cells. - Sock, Elisabeth; Wegner, Michael; et al. (Nature Communications, 2010)
UnivIS-Import:2015-03-09:Pub.2010.med.IB.LPCIPDBI.organo

Oxidative stress-induced posttranslational modifications of alpha-synuclein: specific modification of alpha-synuclein by 4-hydroxy-2-nonenal increases dopaminergic toxicity - Xiang, Wei; Schlachetzki, Johannes; Helling, Stefan; Bussmann, Julia C.; Berlinghof, Marvin; Schäffer, Tilman; Marcus, Katrin; Winkler, Jürgen; Klucken, Jochen; Becker, Cord-Michael; Klucken, Jochen (Molecular and Cellular Neuroscience, 2013)
Aggregation and neurotoxicity of misfolded alpha-synuclein (?Syn) are crucial mechanisms for progressive dopaminergic neurodegeneration associated with Parkinson's disease (PD). Posttranslational modifications (PTMs) of ?Syn caused by oxidative stress, including modification by 4-hydroxy-2-nonenal (HNE-?Syn), nitration (n-?Syn), and oxidation (o-?Syn), have been implicated to promote oligomerization of ?Syn. However, it is yet unclear if these PTMs lead to different types of oligomeric intermediates. Moreover, little is known about which PTM-derived ?Syn species exerts toxicity to dopaminergic cells. In this study, we directly compared aggregation characteristics of HNE-?Syn, n-?Syn, and o-?Syn. Generally, all of them promoted ?Syn oligomerization. Particularly, HNE-?Syn and n-?Syn were more prone to forming oligomers than unmodified ?Syn. Moreover, these PTMs prevented the formation of amyloid-like fibrils, although HNE-?Syn and o-?Syn were able to generate protofibrillar structures. The cellular effects associated with distinct PTMs were studied by exposing modified ?Syn to dopaminergic Lund human mesencephalic (LUHMES) neurons. The cellular toxicity of HNE-?Syn was significantly higher than other PTM species. Furthermore, we tested the toxicity of HNE-?Syn in dopaminergic LUHMES cells and other cell types with low tyrosine hydroxylase (TH) expression, and additionally analyzed the loss of TH-immunoreactive cells in HNE-?Syn-treated LUHMES cells. We observed a selective toxicity of HNE-?Syn to neurons with higher TH expression. Further mechanistic studies showed that HNE-modification apparently increased the interaction of extracellular ?Syn with neurons. Moreover, exposure of differentiated LUHMES cells to HNE-?Syn triggered the production of intracellular reactive oxygen species, preceding neuronal cell death. Antioxidant treatment effectively protected cells from the damage triggered by HNE-?Syn. Our findings suggest a specific pathological effect of HNE-?Syn on dopaminergic neurons.
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Oxidative stress-induced posttranslational modifications of human hemoglobin in erythrocytes - Xiang, Wei; Weisbach, Volker Günter; Sticht, Heinrich; Seebahn, Angela; Bussmann, Julia; Zimmermann, Robert; Becker, Cord-Michael (Archives of Biochemistry and Biophysics, 2013)
Posttranslational modifications (PTMs) have been reported in hemoglobin (Hb) treated with ROS/RNS in cell-free experiments. However, little is known about oxidative PTMs of Hb occurring within the erythrocytes. The aim of this study is to characterize the patterns of Hb PTMs in erythrocytes under oxidative stress. Using mass spectrometry, we investigated specifically methionine/tryptophan oxidation, tyrosine nitration, and the modification via 4-hydroxynonenal (HNE), a product of lipid-peroxidation, on Hb. We demonstrated that the treatment with H(2)O(2)/nitrite induced higher levels of Hb oxidation/nitration in purified Hb preparations than in unpurified hemolysates and erythrocytes, indicating that ROS/RNS are primarily removed by antioxidative mechanisms. We further studied Hb from erythrocytes exposed to ?-irradiation. An irradiation of 30-100 Gy triggered a remarkable increase of intracellular ROS. However, 30 Gy did not induce apparent changes in Hb oxidation/nitration and hemolysis, while Hb oxidation/nitration and hemolysis were significantly enhanced by 100 Gy, suggesting that Hb oxidation/nitration are the consequence of overwhelmed antioxidative mechanisms after oxidative attack and reflect the severity of the oxidative damage of erythrocytes. Although irradiation was known to induce lipid-peroxidation, we could not detect HNE-Hb adducts in irradiated erythrocytes. Analyzing PTM patterns suggests Hb nitration as a more suitable indicator of the oxidative damage of erythrocytes.
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p27kip1 Is Required for Functionally Relevant Adult Hippocampal Neurogenesis in Mice - Hoerster, Henrik; Garthe, Alexander; Walker, Tara L.; Ichwan, Muhammad; Steiner, Barbara; Khan, Muhammad Amir; Lie, Dieter Chichung; Nicola, Zeina; Ramirez-Rodriguez, Gerardo; Kempermann, Gerd (Stem Cells, 2017)
We asked whether cell-cycle associated protein p27kip1 might be involved in the transition of precursor cells to postmitotic maturation in adult hippocampal neurogenesis. p27kip1 was expressed throughout the dentate gyrus with a strong nuclear expression in early postmitotic, calretinin-positive neurons and neuronally determined progenitor cells (type-3 and some type-2b), lower or absent expression in radial glia-like precursor cells (type-1) and type-2a cells and essentially no expression in granule cells. This suggested a transitory role in late proliferative and early postmitotic phases of neurogenesis. Inconsistent with a role limited to cell cycle arrest the acute stimuli, voluntary wheel running (RUN), environmental enrichment (ENR) and kainate-induced seizures increased p27kip1 expressing cells. Sequential short-term combination of RUN and ENR yielded more p27kip1 cells than either stimulus alone, indicating an additive effect. In vitro, p27kip1 was lowly expressed by proliferating precursor cells but increased upon differentiation. In p27kip1-/- mice neurogenesis was reduced in vivo, whereas the number of proliferating cells was increased. Accordingly, the microdissected dentate gyrus of p27kip1-/- mice generated more colonies in the neurosphere assay and an increased number of larger spheres with the differentiation potential unchanged. In p27kip1-/- monolayer cultures, proliferation was increased and cell cycle genes were upregulated. In the Morris water maze p27kip1-/- mice learned the task but were specifically impaired in the reversal phase explainable by the decrease in adult neurogenesis. We conclude that p27kip1 is involved in the decisive step around cell-cycle exit and plays an important role in activity-regulated and functionally relevant adult hippocampal neurogenesis. Stem Cells 2017;35:787-799.
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Palmoplantar Pustular Psoriasis Is Associated with Missense Variants in CARD14, but Not with Loss-of-Function Mutations in IL36RN in European Patients - Moessner, Rotraut; Frambach, Yvonne; Wilsmann-Theis, Dagmar; Loehr, Sabine; Jacobi, Arnd; Weyergraf, Ansgar; Mueller, Michael; Philipp, Sandra; Renner, Regina; Traupe, Heiko; Burkhardt, Harald; Kingo, Kuelli; et al. (Journal of Investigative Dermatology, 2015)
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Paradoxical antidepressant effects of alcohol are related to acid sphingomyelinase and its control of sphingolipid homeostasis - Müller, Christiane; Kalinichenko, Liubov; Tiesel, Jens; Witt, Matthias; Stöckl, Thomas; Sprenger, Eva; Fuchser, Jens; Beckmann, Janine; Praetner, Marc; Huber, Sabine; Amato, Davide; Mühle, Christiane; et al. (Acta Neuropathologica, 2016)
Alcohol is a widely consumed drug that can lead to addiction and severe brain damage. However, alcohol is also used as self-medication for psychiatric problems, such as depression, frequently resulting in depression-alcoholism comorbidity. Here, we identify the first molecular mechanism for alcohol use with the goal to self-medicate and ameliorate the behavioral symptoms of a genetically induced innate depression. An induced over-expression of acid sphingomyelinase (ASM), as was observed in depressed patients, enhanced the consumption of alcohol in a mouse model of depression. ASM hyperactivity facilitates the establishment of the conditioned behavioral effects of alcohol, and thus drug memories. Opposite effects on drinking and alcohol reward learning were observed in animals with reduced ASM function. Importantly, free-choice alcohol drinking-but not forced alcohol exposure-reduces depression-like behavior selectively in depressed animals through the normalization of brain ASM activity. No such effects were observed in normal mice. ASM hyperactivity caused sphingolipid and subsequent monoamine transmitter hypo-activity in the brain. Free-choice alcohol drinking restores nucleus accumbens sphingolipid- and monoamine homeostasis selectively in depressed mice. A gene expression analysis suggested strong control of ASM on the expression of genes related to the regulation of pH, ion transmembrane transport, behavioral fear response, neuroprotection and neuropeptide signaling pathways. These findings suggest that the paradoxical antidepressant effects of alcohol in depressed organisms are mediated by ASM and its control of sphingolipid homeostasis. Both emerge as a new treatment target specifically for depression-induced alcoholism.
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Patch-clamp studies and cell viability assays suggest a distinct site for viroporin inhibitors on the E protein of SARS-CoV-2 - Breitinger, Ulrike; Sedky, Christine Adel; Sticht, Heinrich; Breitinger, Hans Georg (Virology Journal, 2023)
Background: SARS-CoV-2 has caused a worldwide pandemic since December 2019 and the search for pharmaceutical targets against COVID-19 remains an important challenge. Here, we studied the envelope protein E of SARS-CoV and SARS-CoV-2, a highly conserved 75–76 amino acid viroporin that is crucial for virus assembly and release. E protein channels were recombinantly expressed in HEK293 cells, a membrane-directing signal peptide ensured transfer to the plasma membrane. Methods: Viroporin channel activity of both E proteins was investigated using patch-clamp electrophysiology in combination with a cell viability assay. We verified inhibition by classical viroporin inhibitors amantadine, rimantadine and 5-(N,N-hexamethylene)-amiloride, and tested four ivermectin derivatives. Results: Classical inhibitors showed potent activity in patch-clamp recordings and viability assays. In contrast, ivermectin and milbemycin inhibited the E channel in patch-clamp recordings but displayed only moderate activity on the E protein in the cell viability assay, which is also sensitive to general cytotoxic activity of the tested compounds. Nemadectin and ivermectin aglycon were inactive. All ivermectin derivatives were cytotoxic at concentrations > 5 µM, i.e. below the level required for E protein inhibition. Conclusions: This study demonstrates direct inhibition of the SARS-CoV-2 E protein by classical viroporin inhibitors. Ivermectin and milbemycin inhibit the E protein channel but their cytotoxicity argues against clinical application.
CRIS-Team Scopus Importer:2023-07-21
Keywords: Cell viability assay; E protein; Ivermectin derivatives; Patch-clamp electrophysiology; SARS-CoV-2; Viroporin inhibitors; Viroporins

Pathogenic SCN2A variants cause early-stage dysfunction in patient-derived neurons - Asadollahi, Reza; Delvendahl,; Muff, R.; Tan, G.; Rodrieguez, D. G.; Turan, Sören; Russo, M.; Oneda, B.; Joset, P.; Boonsawat, P.; Masood, R.; Mocera, M.; et al. (Human Molecular Genetics, 2023)
Pathogenic heterozygous variants in SCN2A, which encodes the neuronal sodium channel Na(V)1.2, cause different types of epilepsy or intellectual disability (ID)/autism without seizures. Previous studies using mouse models or heterologous systems suggest that Na(V)1.2 channel gain-of-function typically causes epilepsy, whereas loss-of-function leads to ID/autism. How altered channel biophysics translate into patient neurons remains unknown. Here, we investigated iPSC-derived early-stage cortical neurons from ID patients harboring diverse pathogenic SCN2A variants [p.(Leu611Valfs*35); p.(Arg937Cys); p.(Trp1716*)] and compared them with neurons from an epileptic encephalopathy (EE) patient [p.(Glu1803Gly)] and controls. ID neurons consistently expressed lower Na(V)1.2 protein levels. In neurons with the frameshift variant, Na(V)1.2 mRNA and protein levels were reduced by similar to 50%, suggesting nonsense-mediated decay and haploinsufficiency. In other ID neurons, only protein levels were reduced implying Na(V)1.2 instability. Electrophysiological analysis revealed decreased sodium current density and impaired action potential (AP) firing in ID neurons, consistent with reduced Na(V)1.2 levels. In contrast, epilepsy neurons displayed no change in Na(V)1.2 levels or sodium current density, but impaired sodium channel inactivation. Single-cell transcriptomics identified dysregulation of distinct molecular pathways including inhibition of oxidative phosphorylation in neurons with SCN2A haploinsufficiency and activation of calcium signaling and neurotransmission in epilepsy neurons. Together, our patient iPSC-derived neurons reveal characteristic sodium channel dysfunction consistent with biophysical changes previously observed in heterologous systems. Additionally, our model links the channel dysfunction in ID to reduced Na(V)1.2 levels and uncovers impaired AP firing in early-stage neurons. The altered molecular pathways may reflect a homeostatic response to Na(V)1.2 dysfunction and can guide further investigations.
CRIS-Team WoS Importer:2023-05-26

Pathogenic WDFY3 variants cause neurodevelopmental disorders and opposing effects on brain size - Le Duc, Diana; Giulivi, Cecilia; Hiatt, Susan M.; Napoli, Eleonora; Panoutsopoulos, Alexios; Harlan De Crescenzo, Angelo; Kotzaeridou, Urania; Syrbe, Steffen; Anagnostou, Evdokia; Azage, Meron; Bend, Renee; Begtrup, Amber; et al. (Brain, 2019)
The underpinnings of mild to moderate neurodevelopmental delay remain elusive, often leading to late diagnosis and interventions. Here, we present data on exome and genome sequencing as well as array analysis of 13 individuals that point to pathogenic, heterozygous, mostly de novo variants in WDFY3 (significant de novo enrichment P = 0.003) as a monogenic cause of mild and non-specific neurodevelopmental delay. Nine variants were protein-truncating and four missense. Overlapping symptoms included neurodevelopmental delay, intellectual disability, macrocephaly, and psychiatric disorders (autism spectrum disorders/attention deficit hyperactivity disorder). One proband presented with an opposing phenotype of microcephaly and the only missense-variant located in the PH-domain of WDFY3. Findings of this case are supported by previously published data, demonstrating that pathogenic PH-domain variants can lead to microcephaly via canonical Wnt-pathway upregulation. In a separate study, we reported that the autophagy scaffolding protein WDFY3 is required for cerebral cortical size regulation in mice, by controlling proper division of neural progenitors. Here, we show that proliferating cortical neural progenitors of human embryonic brains highly express WDFY3, further supporting a role for this molecule in the regulation of prenatal neurogenesis. We present data on Wnt-pathway dysregulation in Wdfy3-haploinsufficient mice, which display macrocephaly and deficits in motor coordination and associative learning, recapitulating the human phenotype. Consequently, we propose that in humans WDFY3 loss-of-function variants lead to macrocephaly via downregulation of the Wnt pathway. In summary, we present WDFY3 as a novel gene linked to mild to moderate neurodevelopmental delay and intellectual disability and conclude that variants putatively causing haploinsufficiency lead to macrocephaly, while an opposing pathomechanism due to variants in the PH-domain of WDFY3 leads to microcephaly.
CRIS-Team Scopus Importer:2019-09-17
Keywords: WDFY3; brain size; intellectual disability; neurodevelopmental delay

Pathogenic WDFY3 variants cause neurodevelopmental disorders and opposing effects on brain size - Le Duc, D.; Giulivi, C.; Hiatt, S. M.; Napoli, E.; Panoutsopoulos, A.; De Crescenzo, A.; Kotzaeridou, U.; Syrbe, S.; Anagnostou, E.; Azage, M.; Bend, R.; Begtrup, A.; et al. (EUROPEAN JOURNAL OF HUMAN GENETICS, 2019)
CRIS-Team WoS Importer:2019-10-25

Pathophysiologie der alkoholischen Fettleber - Hellerbrand, Claus (Alkoholische Leber- und Krebserkrankungen, 2019)
CRIS-Team WoS Importer:2021-10-18

Pattern of Functional TTX-Resistant Sodium Channels Reveals a Developmental Stage of Human iPSC- and ESC-Derived Nociceptors - Eberhardt, Esther; Havlicek, Steven; Schmidt, Diana; Link, Andrea; Neacsu, Cristian; Kohl, Zacharias; Hampl, Martin; Kist, Andreas; Klinger, Alexandra; Nau, Carla; Schüttler, Jürgen; Alzheimer, Christian; et al. (Stem Cell Reports, 2015)
Human pluripotent stem cells (hPSCs) offer the opportunity to generate neuronal cells, including nociceptors. Using a chemical-based approach, we generated nociceptive sensory neurons from HUES6 embryonic stem cells and retrovirally reprogrammed induced hPSCs derived from fibroblasts. The nociceptive neurons expressed respective markers and showed tetrodotoxin-sensitive (TTXs) and -resistant (TTXr) voltage-gated sodium currents in patch-clamp experiments. In contrast to their counterparts from rodent dorsal root ganglia, TTXr currents of hPSC-derived nociceptors unexpectedly displayed a significantly more hyperpolarized voltage dependence of activation and fast inactivation. This apparent discrepancy is most likely due to a substantial expression of the developmentally important sodium channel NAV1.5. In view of the obstacles to recapitulate neuropathic pain in animal models, our data advance hPSC-derived nociceptors as a better model to study developmental and pathogenetic processes in human nociceptive neurons and to develop more specific small molecules to attenuate pain.
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PBAF Subunit Pbrm1 Selectively Influences the Transition from Progenitors to Pre-Myelinating Cells during Oligodendrocyte Development - Waldhauser, Vanessa; Baroti, Tina; Fröb, Franziska; Wegner, Michael (Cells, 2023)
Oligodendrocyte development is accompanied by defined changes in the state of chromatin that are brought about by chromatin remodeling complexes. Many such remodeling complexes exist, but only a few have been studied for their impact on oligodendrocytes as the myelin-forming cells of the central nervous system. To define the role of the PBAF remodeling complex, we focused on Pbrm1 as an essential subunit of the PBAF complex and specifically deleted it in the oligodendrocyte lineage at different times of development in the mouse. Deletion in late oligodendrocyte progenitor cells did not lead to substantial changes in the ensuing differentiation and myelination processes. However, when Pbrm1 loss had already occurred in oligodendrocyte progenitor cells shortly after their specification, fewer cells entered the pre-myelinating state. The reduction in pre-myelinating cells later translated into a comparable reduction in myelinating oligodendrocytes. We conclude that Pbrm1 and, by inference, the activity of the PBAF complex is specifically required at the transition from oligodendrocyte progenitor to pre-myelinating oligodendrocyte and ensures the generation of normal numbers of myelinating oligodendrocytes.
CRIS-Team Scopus Importer:2023-07-28
Keywords: chromatin remodeling; glia; myelin; oligodendrocyte; polybromo-1

Peptide labeling with photoactivatable trifunctional cadaverine derivative and identification of interacting partners by biotin transfer - App, Christine; Knop, Jana; Huff, Thomas; Seebahn, Angela; Becker, Cord-Michael; Iavarone, Federica; Castagnola, Massimo; Hannappel, Ewald (Analytical Biochemistry, 2014)
A new photoactivatable trifunctional cross-linker, cBED (cadaverine-2-[6-(biotinamido)-2-(p-azidobenzamido) hexanoamido]ethyl-1,3'-dithiopropionate), was synthesized by chemical conversion of sulfo-SBED (sulfosuccinimidyl-2-[6-(biotinamido)-2-(p-azidobenzamido) hexanoamido]ethyl-1,3'-dithiopropionate) with cadaverine. This cross-linker was purified by reversed-phase high-performance liquid chromatography (RP-HPLC) and characterized using matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) analysis. cBED is based on sulfo-SBED that has a photoactivatable azido group, a cleavable disulfide bond for label transfer methods, and a biotin moiety for highly sensitive biotin/avidin detection. By ultraviolet (UV) light, the azido group is converted to a reactive nitrene, transforming transient bindings of interacting structures to covalent bonds. In contrast to the sulfo-N-hydroxysuccinimide (sulfo-NHS) moiety of sulfo-SBED, which attaches quite unspecifically to amino groups, cBED includes a cadaverine moiety that can be attached by transglutaminase more specifically to certain glutamine residues. For instance, thymosin ?4 can be labeled with cBED using tissue transglutaminase. By high-resolution HPLC/ESI-MS (electrospray ionization-mass spectrometry) and tandem MS (MS/MS) of the trypsin digest, it was established that glutamine residues at positions 23 and 36 were labeled, whereas Q39 showed no reactivity. The covalent binding of cBED to thymosin ?4 did not influence its G-actin sequestering activity, and the complex could be used to identify new interaction partners. Therefore, cBED can be used to better understand the multifunctional role of thymosin ?4 as well as of other proteins and peptides.
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Peptides presenting the binding site of human CD4 for the HIV-1 envelope glycoprotein gp120 - Meier, Julia; Kaßler, Kristin; Sticht, Heinrich; Eichler, Jutta (Beilstein Journal of Organic Chemistry, 2012)
Based on the structure of the HIV-1 glycoprotein gp120 in complex with its cellular receptor CD4, we have designed and synthesized peptides that mimic the binding site of CD4 for gp120. The ability of these peptides to bind to gp120 can be strongly enhanced by increasing their conformational stability through cyclization, as evidenced by binding assays, as well as through molecular-dynamics simulations of peptide-gp120 complexes. The specificity of the peptide-gp120 interaction was demonstrated by using peptide variants, in which key residues for the interaction with gp120 were replaced by alanine or D-amino acids.
EVALuna2:26259

Performance of scientific cameras with different sensor types in measuring dynamic processes in fluorescence microscopy. - Jung, Jasmin; Weisenburger, S; Albert, S; Gilbert, Daniel; Friedrich, Oliver; Eulenburg, Volker; Kornhuber, Johannes; Groemer, Teja W. (Microscopy research and technique, 2013)
The plethora of available scientific cameras of different types challenges the biologically oriented experimenter when picking the appropriate camera for his experiment. In this study, we chose to investigate camera performances in a typical nonsingle molecule situation in life sciences, that is, quantitative measurements of fluorescence intensity changes from video data with typically skewed intensity distributions. Here, intensity profile dynamics of pH-sensors upon triggered changes of pH-environments in living cells served as a model system. The following camera types were tested: sCMOS, CCD (scientific and nonscientific) and EM-CCD (back- and front-illuminated). We found that although the EM-CCD cameras achieved the best absolute spatial SNR (signal-to-noise ratio) values, the sCMOS was at least of equal performance when the spatial SNR was related to the effective dynamic range, and it was superior in terms of temporal SNR. In the measurements of triggered intensity changes, the sCMOS camera had the advantage that it used the smallest fraction of its dynamic range when depicting intensity changes, and thus featured the best SNR at full usage of its dynamic range.

Pharmacological inhibition of mtorc2 reduces migration and metastasis in melanoma - Guenzle, Jessica; Akasaka, Harue; Joechle, Katharina; Reichardt, Wilfried; Venkatasamy, Aina; Hoeppner, Jens; Hellerbrand, Claus; Fichtner-Feigl, Stefan; Lang, Sven A. (International Journal of Molecular Sciences, 2021)
Despite recent advances in therapy, liver metastasis from melanoma is still associated with poor prognosis. Although targeting the mTOR signaling pathway exerts potent anti-tumor activity, little is known about specific mTORC2 inhibition regarding liver metastasis. Using the novel mTORC2 specific inhibitor JR-AB2-011, we show significantly reduced migration and invasion capacity by-impaired activation of MMP2 in melanoma cells. In addition, blockade of mTORC2 induces cell death by non-apoptotic pathways and reduces tumor cell proliferation rate dose-dependently. Furthermore, therapy with JR-AB2-011 as determined by in vivo imaging and necropsy. Hence, our study for a significant reduction of liver metastasis was detected in a syngeneic murine metastasis model upon the first time highlights the impact of the pharmacological blockade of mTORC2 as a potent novel anti-cancer approach for liver metastasis from melanoma.
CRIS-Team Scopus Importer:2021-01-08
Keywords: Melanoma; Metastasis; Migration; MTORC2

Phenotype of the first patient harboring a de novo in-frame deletion in the LisH (LIS1 homology) domain of the WDR26 gene - Steindl, K.; Kraemer, D.; Gogoll, L.; Zanoni, P.; Sticht, Heinrich; Rauch, A. (EUROPEAN JOURNAL OF HUMAN GENETICS, 2019)
CRIS-Team WoS Importer:2019-10-25

Phenotypic variability in a large Czech family with a Dynamin 2-associated Charcot-Marie-Tooth neuropathy - Haberlova, J.; Mazanec, R.; Ridzon, P.; Barankova, L.; Nuernberg, G.; Nuernberg, P.; Sticht, Heinrich; Hühne, Kathrin; Seeman, P.; Rautenstrauss, Bernd (Journal of Neurogenetics, 2011)
Mutations in the Dynamin 2 gene (DNM2) cause autosomal dominant centronuclear myopathy or autosomal dominant (AD) Charcot-Marie-Tooth (CMT) disease. Here the authors report one large Czech family with 15 members affected with an AD CMT phenotype of extraordinary variability. Genetic linkage analysis using SNP arrays revealed a locus of about 9.6 Mb on chromosome 19p13.1-13.2. In this critical interval, 373 genes were located. The only gene herein known to be associated with an intermediate type of CMT was Dynamin 2 (DNM2). Subsequent sequence analysis of the DNM2 gene in the index patient revealed a novel missense mutation p.Met580Thr. This missense mutation segregated with the neuropathy, indicating the causal character of this mutation. The phenotype of CMT in this family shows mild to moderate impairment with relatively preserved upper limbs and a very broad range of the onset of clinical symptoms from an early onset around the age of 12 to the late onset during the fifth decade. Electrophysiology showed an intermediate type of peripheral neuropathy. The motor median nerve conduction velocity varied from 36 m/s to normal values with signs of asymmetrical affection of peripheral nerves. No additional symptoms such as cranial nerve involvement, cataract, and signs of neutropenia or myopathy syndrome were observed in any member of the family yet. The progression was slow with no loss of ambulation. The authors suggest that the characterization of clinical variability in a single family may help to direct the genetic analysis directly to the rarely observed DNM2 mutations.
EVALuna2:26266

Phosphorylation Modulates the Subcellular Localization of SOX11 - Balta, Elli-Anna; Wittmann, Marie-Theres; Jung, Matthias; Sock, Elisabeth; Häberle, Benjamin; Heim, Birgit; Von Zweydorf, Felix; Heppt, Jana; von Wittgenstein, Julia; Gloeckner, Christian Johannes; Lie, Dieter Chichung (Frontiers in Molecular Neuroscience, 2018)
SOX11 is a key Transcription Factor (TF) in the regulation of embryonic and adult neurogenesis, whose mutation has recently been linked to an intellectual disability syndrome in humans. SOX11's transient activity during neurogenesis is critical to ensure the precise execution of the neurogenic program. Here, we report that SOX11 displays differential subcellular localizations during the course of neurogenesis. Western-Blot analysis of embryonic mouse brain lysates indicated that SOX11 is post-translationally modified by phosphorylation. Using Mass Spectrometry, we found 10 serine residues in the SOX11 protein that are putatively phosphorylated. Systematic analysis of phospho-mutant SOX11 resulted in the identification of the S30 residue, whose phosphorylation promotes nuclear over cytoplasmic localization of SOX11. Collectively, these findings uncover phosphorylation as a novel layer of regulation of the intellectual disability gene Sox11.
EVALuna2:35742

Phosphorylation of the neurogenic transcription factor SOX11 on serine 133 modulates neuronal morphogenesis - Balta, Elli-Anna; Schäffner, Iris; Wittmann, Marie-Theres; Sock, Elisabeth; Von Zweydorf, Felix; von Wittgenstein, Julia; Steib, Kathrin; Heim, Birgit; Kremmer, Elisabeth; Häberle, Benjamin; Ueffing, Marius; Lie, Dieter Chichung; et al. (Scientific Reports, 2018)
The intellectual disability gene, Sox11, encodes for a critical neurodevelopmental transcription factor with functions in precursor survival, neuronal fate determination, migration and morphogenesis. The mechanisms regulating SOX11's activity remain largely unknown. Mass spectrometric analysis uncovered that SOX11 can be post-translationally modified by phosphorylation. Here, we report that phosphorylatable serines surrounding the high-mobility group box modulate SOX11's transcriptional activity. Through Mass Spectrometry (MS), co-immunoprecipitation assays and in vitro phosphorylation assays followed by MS we verified that protein kinase A (PKA) interacts with SOX11 and phosphorylates it on S133. In vivo replacement of SoxC factors in developing adult-generated hippocampal neurons with SOX11 S133 phospho-mutants indicated that phosphorylation on S133 modulates dendrite development of adult-born dentate granule neurons, while reporter assays suggested that S133 phosphorylation fine-tunes the activation of select target genes. These data provide novel insight into the control of the critical neurodevelopmental regulator SOX11 and imply SOX11 as a mediator of PKA-regulated neuronal development.
EVALuna2:35738

Phototherapy-induced elevation of serum level of melanoma inhibitory activity - Datz, Elisabeth; Zeman, Florian; Koller, Michael; Szeimies, Rolf Markus; Berneburg, Mark; Landthaler, Michael; Boßerhoff, Anja Katrin; Karrer, Sigrid (Photodermatology Photoimmunology & Photomedicine, 2019)
Background: Phototherapy is a frequently used treatment modality for a variety of dermatologic diseases. UV radiation has different effects on the skin, for example increased production and release of cytokines and other proteins, and is involved in the initiation and progression of skin cancer. Objective of this clinical trial was to investigate potential systemic effects of UV phototherapy on cytokine profiles in blood. Methods: In a prospective, mono-centric, one-armed study, the serum levels of the melanoma tumour marker “melanoma inhibitory activity” (MIA), Il-1α, Il-4, Il-6, Il-10, TNF-α and IFN-γ of 115 patients with different skin diseases were compared before and 24-48 hours as well as 2-4 weeks after the first phototherapy with PUVA (psoralen and ultraviolet A), UVA or UVB, or both. Data were analysed using linear mixed models. Results: Estimated marginal means of MIA levels were 6.05 ng/mL (95%-CI: 5.37-6.72, range: 2.83-14.49) before the first treatment, which had significantly increased to 6.79 ng/mL 2-4 weeks after the first phototherapy (CI 95%: 6.12-7.47, range: 3.09-15.45; P = 0.0042). MIA levels 2-4 weeks after the first phototherapy were significantly higher than 24-48 hours after the first phototherapy (P = 0.0083). 2-4 weeks after the first treatment, TNF-α levels had decreased significantly (P = 0.033) more in patients with psoriasis who had responded well to phototherapy than in patients unresponsive to treatment. Serum levels of the other cytokines had not changed significantly. Conclusions: Short-term phototherapy significantly increased the serum levels of the melanoma tumour marker MIA. The potential clinical relevance of these findings (ie an increased risk of melanoma) is unclear and should be further investigated.
CRIS-Team Scopus Importer:2019-07-30
Keywords: melanoma; melanoma inhibitory activity; phototherapy; psoriasis; skin diseases; study; UV therapy

Pirin is a prognostic marker of human melanoma that dampens the proliferation of malignant cells by downregulating JARID1B/KDM5B expression - Penas, Cristina; Arroyo-Berdugo, Yoana; Apraiz, Aintzane; Rasero, Javier; Muñoa-Hoyos, Iraia; Andollo, Noelia; Cancho-Galán, Goikoane; Izu, Rosa; Gardeazabal, Jesús; Ezkurra, Pilar A.; Subiran, Nerea; Alvarez-Dominguez, Carmen; et al. (Scientific Reports, 2023)
Originally considered to act as a transcriptional co-factor, Pirin has recently been reported to play a role in tumorigenesis and the malignant progression of many tumors. Here, we have analyzed the diagnostic and prognostic value of Pirin expression in the early stages of melanoma, and its role in the biology of melanocytic cells. Pirin expression was analyzed in a total of 314 melanoma biopsies, correlating this feature with the patient’s clinical course. Moreover, PIR downregulated primary melanocytes were analyzed by RNA sequencing, and the data obtained were validated in human melanoma cell lines overexpressing PIR by functional assays. The immunohistochemistry multivariate analysis revealed that early melanomas with stronger Pirin expression were more than twice as likely to develop metastases during the follow-up. Transcriptome analysis of PIR downregulated melanocytes showed a dampening of genes involved in the G1/S transition, cell proliferation, and cell migration. In addition, an in silico approach predicted that JARID1B as a potential transcriptional regulator that lies between PIR and its downstream modulated genes, which was corroborated by co-transfection experiments and functional analysis. Together, the data obtained indicated that Pirin could be a useful marker for the metastatic progression of melanoma and that it participates in the proliferation of melanoma cells by regulating the slow-cycling JARID1B gene.
CRIS-Team Scopus Importer:2023-06-30

Pivotal Role for CD16+ Monocytes in Immune Surveillance of the Central Nervous System - Waschbisch, Anne; Schröder, Sina; Schraudner, Dana; Sammet, Laura; Weksler, Babette; Melms, Arthur; Pfeifenbring, Sabine; Stadelmann, Christine; Schwab, Stefan; Linker, Ralf A. (Journal of Immunology, 2016)
Monocytes represent a heterogeneous population of primary immune effector cells. At least three different subsets can be distinguished based on expression of the low-affinity Fc?RIII: CD14(++)CD16 -: classical monocytes, CD14(++)CD16(+) intermediate monocytes, and CD14(+)CD16 ++: non-classical monocytes. Whereas CD16 -: classical monocytes are considered key players in multiple sclerosis (MS), little is known on CD16(+) monocytes and how they contribute to the disease. In this study, we examined the frequency and phenotype of monocyte subpopulations in peripheral blood, cerebrospinal fluid (CSF), and brain biopsy material derived from MS patients and controls. Furthermore, we addressed a possible monocyte dysfunction in MS and analyzed migratory properties of monocyte subsets using human brain microvascular endothelial cells. Our ex vivo studies demonstrated that CD16(+) monocyte subpopulations are functional but numerically reduced in the peripheral blood of MS patients. CD16(+) monocytes with an intermediate-like phenotype were found to be enriched in CSF and dominated the CSF monocyte population under noninflammatory conditions. In contrast, an inversed CD16(+) to CD16 -: CSF monocyte ratio was observed in MS patients with relapsing-remitting disease. Newly infiltrating, hematogenous CD16(+) monocytes were detected in a perivascular location within active MS lesions, and CD16(+) monocytes facilitated CD4(+) T cell trafficking in a blood -: brain barrier model. Our findings support an important role of CD16(+) monocytes in the steady-state immune surveillance of the CNS and suggest that CD16(+) monocytes shift to sites of inflammation and contribute to the breakdown of the blood-brain barrier in CNS autoimmune diseases.
EVALuna2:22432

PKCζ-interacting protein ZIP3 is generated by intronic polyadenylation, and is expressed in the brain and retina of the rat. - Urbanczyk, Andreas; Jünemann, Anselm; Enz, Ralf (Biochemical Journal, 2011)
Scaffold proteins contain multiple protein - protein interaction modules that physically assemble functionally related proteins into larger complexes. ZIPs [PKC (protein kinase C) ζ-interacting proteins] link the enzymatic activity of the atypical PKC isoforms PKCλ/ι or PKCζ to target proteins and are associated with neurodegenerative disorders. In the rat, alternative splicing generates three ZIP variants. Previously, we identified the ZIP3 transcript, containing 13 C-terminal amino acids encoded by intron 4, in the rat CNS (central nervous system). In the present study, we identified intronic polyadenylation signals in rat and hu man ZIP genes [known as SQSTM1 (sequestosome-1) in humans] and detected the corresponding ZIP3-like transcripts. In addition, we generated ZIP3-specific immune sera and observed expression of the protein in the brain and retina of the adult rat. In the retina, ZIP3 is present in nuclear layers where it co-localizes with PKCζ. An immune serum recognizing all three ZIP isoforms labelled the same cells as the newly generated ZIP3-specific antibodies and, in addition, stained both synaptic layers of the retina. There, ZIPs are localized in axon terminals of rod bipolar cells that also contain ZIP-interacting PKCζ and GABA C (γ-aminobutyric acid type C) receptors. In summary, we detected ZIP3-like transcripts in ratand human-derived samples and describe the expression of ZIP3 in the rat CNS. © The Authors Journal compilation © 2011 Biochemical Society.
UnivIS-Import:2015-04-14:Pub.2011.med.IB.profes_1.pkc950
Keywords: γ-aminobutyric acid type C (GABA; p62; Protein kinase Cζ-interacting protein 3 (ZIP3); Retina; Sequestosome-1 (SQSTM1)

Placental failure in mice lacking the mammalian homolog of glial cells missing, GCMa - Wegner, Michael; et al. (Molecular and Cellular Biology, 2000)
The GCM family of transcription factors consists of Drosophila melanogaster GCM, an important regulator of gliogenesis in the fly, and its two mammalian homologs, GCMa and GCMb. To clarify the function of these mammalian homologs, we deleted GCMa in mice. Genetic ablation of murine GCMa (mGCMa) is embryonic lethal, with mice dying between 9.5 and 10 days postcoitum. At the time of death, no abnormalities were apparent in the embryo proper. Nervous system development, in particular, was not impaired, as might have been expected in analogy to Drosophila GCM. Instead, placental failure was the cause of death. In agreement with the selective expression of mGCMa in labyrinthine trophoblasts, mutant placentas did not develop a functional labyrinth layer, which is necessary for nutrient and gas exchange between maternal and fetal blood. Only a few fetal blood vessels entered the placenta, and these failed to thrive and branch normally. Labyrinthine trophoblasts did not differentiate. All other layers of the placenta, including spongiotrophoblast and giant cell layer, formed normally. Our results indicate that mGCMa plays a critical role in trophoblast differentiation and the signal transduction processes required for normal vascularization of the placenta.
UnivIS-Import:2015-03-05:Pub.2000.med.IB.LPCIPDBI.placen

PNUTS forms a trimeric protein complex with GABAC receptors and protein phosphatase 1. - Rose, Melanie; Dütting, Eva; Schröder, Nadja; Sticht, Heinrich; Brandstätter, Johann Helmut; Enz, Ralf (Molecular and Cellular Neuroscience, 2008)
Phosphorylation and dephosphorylation of neurotransmitter receptors represent an important mechanism to regulate synaptic signal transduction. Here, we identified PNUTS, a targeting subunit of protein phosphatase 1 (PP1) as a new binding partner of GABAC receptors. In the mammalian retina, PNUTS is co-expressed with GABAC receptors and PP1 in bipolar cells. PNUTS and PP1 were detected in membrane protein preparations of the retina and precipitate with GABAC receptor specific antibodies. Furthermore, PNUTS shuttles from the nucleus to the membrane in cells co-expressing GABAC receptors. We show simultaneous binding of PP1 and GABAC receptors to different domains of PNUTS, demonstrating that PNUTS cross-links PP1 and GABAC receptors. Finally, modeling studies showed that the PP1 docking motif of PNUTS fits into the binding pocket on the enzyme surface, despite a C-terminal adjacent proline. We suggest that PNUTS targets PP1 to synaptic sites, acting as a temporary bridge between the phosphatase and GABAC receptors. © 2007 Elsevier Inc. All rights reserved.
UnivIS-Import:2015-04-14:Pub.2008.med.IB.profes_1.pnutsf_1
Keywords: Docking motif; GABA receptor; PP1C; Protein interaction; Retina; rho subunit

Polymorphisms in the Hsp70 gene locus are genetically associated with systemic lupus erythematosus - Fuernrohr, Barbara G.; Wach, Sven; Kelly, Jennifer A.; Haslbeck, Martin; Weber, Christian K.; Stach, Christian M.; Hueber, Axel J.; Graef, Daniela; Spriewald, Bernd M.; Manger, Karin; Herrmann, Martin; Kaufman, Kenneth M.; et al. (Annals of the Rheumatic Diseases, 2010)
Background: Heat shock proteins (Hsps) play a role in the delivery and presentation of antigenic peptides and are thought to be involved in the pathogenesis of multifactorial diseases. Objective: To investigate genes encoding cytosolic Hsp70 proteins for associations of allelic variants with systemic lupus erythematosus (SLE). Methods: Case-control studies of two independent Caucasian SLE cohorts were performed. In a haplotype-tagging single-nucleotide polymorphism approach, common variants of HspA1L, HspA1A and HspA1B were genotyped and principal component analyses were performed for the cohort from the Oklahoma Medical Research Foundation (OMRF). Relative quantification of mRNA was carried out for each Hsp70 gene in healthy controls. Conditional regression analysis was performed to determine if allelic variants in Hsp70 act independently of HLA-DR3. Results: On analysis of common genetic variants of HspA1L, HspA1A and HspA1B, a haplotype significantly associated with SLE in the Erlangen-SLE cohort was identified, which was confirmed in the OMRF cohort. Depending on the cohorts, OR ranging from 1.43 to 1.88 and 2.64 to 3.16 was observed for individuals heterozygous and homozygous for the associated haplotype, respectively. Patients carrying the risk haplotype or the risk allele more often displayed autoantibodies to Ro and La in both cohorts. In healthy controls bearing this haplotype, the amount of HspA1A mRNA was significantly increased, whereas total Hsp70 protein concentration was not altered. Conclusions: Allelic variants of the Hsp70 genes are significantly associated with SLE in Caucasians, independently of HLA-DR3, and correlate with the presence of autoantibodies to Ro and La. Hence, the Hsp70 gene locus appears to be involved in SLE pathogenesis.

Pontocerebellar hypoplasia due to bi-allelic variants in MINPP1 - Appelhof, Bart; Wagner, Matias; Hoefele, Julia; Heinze, Anja; Roser, Timo; Koch-Hogrebe, Margarete; Roosendaal, Stefan D.; Dehghani, Mohammadreza; Mehrjardi, Mohammad Yahya Vahidi; Torti, Erin; Houlden, Henry; Maroofian, Reza; et al. (European Journal of Human Genetics, 2021)
Pontocerebellar hypoplasia (PCH) describes a group of rare heterogeneous neurodegenerative diseases with prenatal onset. Here we describe eight children with PCH from four unrelated families harboring the homozygous MINPP1 (NM_004897.4) variants; c.75_94del, p.(Leu27Argfs*39), c.851 C > A, p.(Ala284Asp), c.1210 C > T, p.(Arg404*), and c.992 T > G, p.(Ile331Ser). The homozygous p.(Leu27Argfs*39) change is predicted to result in a complete absence of MINPP1. The p.(Arg404*) would likely lead to a nonsense mediated decay, or alternatively, a loss of several secondary structure elements impairing protein folding. The missense p.(Ala284Asp) affects a buried, hydrophobic residue within the globular domain. The introduction of aspartic acid is energetically highly unfavorable and therefore predicted to cause a significant reduction in protein stability. The missense p.(Ile331Ser) affects the tight hydrophobic interactions of the isoleucine by the disruption of the polar side chain of serine, destabilizing the structure of MINPP1. The overlap of the above-mentioned genotypes and phenotypes is highly improbable by chance. MINPP1 is the only enzyme that hydrolyses inositol phosphates in the endoplasmic reticulum lumen and several studies support its role in stress induced apoptosis. The pathomechanism explaining the disease mechanism remains unknown, however several others genes of the inositol phosphatase metabolism (e.g., INPP5K, FIG4, INPP5E, ITPR1) are correlated with phenotypes of neurodevelopmental disorders. Taken together, we present MINPP1 as a novel autosomal recessive pontocerebellar hypoplasia gene.
CRIS-Team Scopus Importer:2021-05-14

Postnatal Sox6 Regulates Synaptic Function of Cortical Parvalbumin-Expressing Neurons - Munguba, Hermany; Chattopadhyaya, Bidisha; Nilsson, Stephan; Carrico, Josianne N.; Memic, Fatima; Oberst, Polina; Batista-Brito, Renata; Munoz-Manchado, Ana Belen; Wegner, Michael; Fishell, Gordon; Di Cristo, Graziella; Hjerling-Leffler, Jens (Journal of Neuroscience, 2021)
Cortical parvalbumin-expressing (Pvalb(+)) neurons provide robust inhibition to neighboring pyramidal neurons, crucial for the proper functioning of cortical networks. This class of inhibitory neurons undergoes extensive synaptic formation and maturation during the first weeks after birth and continue to dynamically maintain their synaptic output throughout adulthood. While several transcription factors, such as Nkx2-1, Lhx6, and Sox6, are known to be necessary for the differentiation of progenitors into Pvalb(+) neurons, which transcriptional programs underlie the postnatal maturation and maintenance of Pvalb(+) neurons' innervation and synaptic function remains largely unknown. Because Sox6 is continuously expressed in Pvalb(+) neurons until adulthood, we used conditional knock-out strategies to investigate its putative role in the postnatal maturation and synaptic function of cortical Pvalb(+) neurons in mice of both sexes. We found that early postnatal loss of Sox6 in Pvalb(+) neurons leads to failure of synaptic bouton growth, whereas later removal in mature Pvalb(+) neurons in the adult causes shrinkage of already established synaptic boutons. Paired recordings between Pvalb(+) neurons and pyramidal neurons revealed reduced release probability and increased failure rate of Pvalb(+) neurons' synaptic output. Furthermore, Pvalb(+) neurons lacking Sox6 display reduced expression of full-length tropomyosin-receptor kinase B (TrkB), a key modulator of GABAergic transmission. Once re-expressed in neurons lacking Sox6, TrkB was sufficient to rescue the morphologic synaptic phenotype. Finally, we showed that Sox6 mRNA levels were increased by motor training. Our data thus suggest a constitutive role for Sox6 in the maintenance of synaptic output from Pvalb(+) neurons into adulthood.
CRIS-Team WoS Importer:2021-11-12

Post-transcriptional regulation of Argonaute2 in malignant melanoma - Linck-Paulus, L.; Voeller, D.; Meister, G.; Boßerhoff, Anja Katrin (EXPERIMENTAL DERMATOLOGY, 2019)
CRIS-Team WoS Importer:2019-03-26

Posttranslational modification and mutation of histidine 50 trigger alpha synuclein aggregation and toxicity - Xiang, Wei; Menges, Stefanie; Schlachetzki, Johannes; Meixner, Holger; Hoffmann, Anna-Carin; Schlötzer-Schrehardt, Ursula; Becker, Cord-Michael; Winkler, Jürgen; Klucken, Jochen; Klucken, Jochen (Molecular Neurodegeneration, 2015)
Aggregation and aggregation-mediated formation of toxic alpha synuclein (aSyn) species have been linked to the pathogenesis of sporadic and monogenic Parkinson's disease (PD). A novel H50Q mutation of aSyn, resulting in the substitution of histidine by glutamine, has recently been identified in PD patients. We have previously shown that the lipid peroxidation product 4-hydroxy-2-nonenal (HNE) induces the formation of HNE-aSyn adducts, thereby promoting aSyn oligomerization and increasing its extracellular toxicity to human dopaminergic neurons. Intriguingly, we identified histidine 50 (H50) of aSyn as one of the HNE modification target residues. These converging lines of evidence support the hypothesis that changes in H50 via posttranslational modification (PTM) and mutation trigger the formation of aggregated, toxic aSyn species, which interfere with cellular homeostasis. In the present study, we aim to elucidate 1) the role of H50 in HNE-mediated aSyn aggregation and toxicity, and 2) the impact of H50 mutation on aSyn pathology. Besides the PD-related H50Q, we analyze a PD-unrelated control mutation, in which H50 is replaced by an arginine residue (H50R).Analysis of HNE-treated aSyn revealed that H50 is the most susceptible residue of aSyn to HNE modification and is crucial for HNE-mediated aSyn oligomerization. Overexpression of aSyn with substituted H50 in H4 neuroglioma cells reduced HNE-induced cell damage, indicating a pivotal role of H50 in HNE modification-induced aSyn toxicity. Furthermore, we showed in vitro that H50Q/R mutations substantially increase the formation of high density and fibrillar aSyn species, and potentiate the oligomerization propensity of aSyn in the presence of a nitrating agent. Cell-based experiments also revealed that overexpression of H50Q aSyn in H4 cells promotes aSyn oligomerization. Importantly, overexpression of both H50Q/R aSyn mutants in H4 cells significantly increased cell death when compared to wild type aSyn. This increase in cell death was further exacerbated by the application of H2O2.A dual approach addressing alterations of H50 showed that either H50 PTM or mutation trigger aSyn aggregation and toxicity, suggesting an important role of aSyn H50 in the pathogenesis of both sporadic and monogenic PD.
EVALuna2:4709

Potent Tau Aggregation Inhibitor D-Peptides Selected against Tau-Repeat 2 Using Mirror Image Phage Display - Malhis, Marwa; Kaniyappan, Senthilvelrajan; Aillaud, Isabelle; Chandupatla, Ram Reddy; Ramirez, Lisa Marie; Zweckstetter, Markus; Horn, Anselm; Mandelkow, Eckhard; Sticht, Heinrich; Funke, Susanne Aileen (ChemBioChem, 2021)
Alzheimer's disease and other Tauopathies are associated with neurofibrillary tangles composed of Tau protein, as well as toxic Tau oligomers. Therefore, inhibitors of pathological Tau aggregation are potentially useful candidates for future therapies targeting Tauopathies. Two hexapeptides within Tau, designated PHF6* (275-VQIINK-280) and PHF6 (306-VQIVYK-311), are known to promote Tau aggregation. Recently, the PHF6* segment has been described as the more potent driver of Tau aggregation. We therefore employed mirror-image phage display with a large peptide library to identify PHF6* fibril binding peptides consisting of D-enantiomeric amino acids. The suitability of D-enantiomeric peptides for in vivo applications, which are protease stable and less immunogenic than L-peptides, has already been demonstrated. The identified D-enantiomeric peptide MMD3 and its retro-inverso form, designated MMD3rev, inhibited in vitro fibrillization of the PHF6* peptide, the repeat domain of Tau as well as full-length Tau. Dynamic light scattering, pelleting assays and atomic force microscopy demonstrated that MMD3 prevents the formation of tau β-sheet-rich fibrils by diverting Tau into large amorphous aggregates. NMR data suggest that the D-enantiomeric peptides bound to Tau monomers with rather low affinity, but ELISA (enzyme-linked immunosorbent assay) data demonstrated binding to PHF6* and full length Tau fibrils. In addition, molecular insight into the binding mode of MMD3 to PHF6* fibrils were gained by in silico modelling. The identified PHF6*-targeting peptides were able to penetrate cells. The study establishes PHF6* fibril binding peptides consisting of D-enantiomeric amino acids as potential molecules for therapeutic and diagnostic applications in AD research.
CRIS-Team Scopus Importer:2021-09-17
Keywords: Alzheimer's disease; D-peptides; phage display; tau aggregation inhibitors; therapy

Pre-incubation of corneal donor tissue with soluble CD83 improves graft survival via the induction of pro-resolving macrophages - Peckert-Maier, Katrin; Schoenberg, Alfrun; Wild, Andreas; Royzman, Dmytro; Braun, Gabriele; Hadrian, Karina; Tripal, Philipp; Cursiefen, Claus; Steinkasserer, Alexander; Zinser, Elisabeth; Bock, Felix (WOUND REPAIR AND REGENERATION, 2022)
CRIS-Team WoS Importer:2022-09-16

Premature Osteoarthritis as Presenting Sign of Type II Collagenopathy: A Case Report and Literature Review - Husar-Memmer, Emma; Ekici, Arif Bülent; Al Kaissi, Ali; Sticht, Heinrich; Manger, Bernhard; Schett, Georg; Zwerina, Jochen (Seminars in Arthritis and Rheumatism, 2013)
Osteoarthritis (OA) is a frequent, chronic, and often disabling disease. Early-onset OA should prompt rheumatologists to search for underlying causes. We describe the clinical presentation and diagnosis of a patient with severe premature OA.We report a patient with severe polyarticular OA starting in young adulthood due to a heterozygous mutation in the COL2A1 gene. We discuss the clinical features, diagnosis, and known mutations of previously reported cases identified through a PubMed literature review.A 43-year-old Caucasian woman of normal stature presented with a 24-year history of symmetrical polyarticular OA involving both large and small joints. At the time of presentation, the patient already underwent 6 joint replacement surgeries. Family history was unremarkable. Clinical, serologic, radiographic, and histologic studies did not reveal any specific cause for this unusual clinical presentation. Genetic analysis revealed a heterozygous COL2A1 mutation (R519C) consistent with the clinical phenotype. Reviewing the literature, we discuss the clinical spectrum of type II collagenopathies emphasizing premature OA as the sole clinical manifestation.Unusual clinical presentations of OA should prompt investigations to search for an underlying cause. Type II collagenopathy should be considered in young adults with severe symmetrical OA even in the absence of other clinical features. A correct diagnosis allows classification and genetic counseling of the patient.
EVALuna2:9163

PreMosa: extracting 2D surfaces from 3D microscopy mosaics - Blasse, Corinna; Saalfeld, Stephan; Etournay, Raphael; Sagner, Andreas; Eaton, Suzanne; Myers, Eugene W. (Bioinformatics, 2017)

Prenatal androgen receptor activation determines adult alcohol and water drinking in a sex-specific way - Huber, Sabine; Zoicas, Iulia; Reichel, Martin; Mühle, Christiane; Büttner, Christian; Ekici, Arif Bülent; Eulenburg, Volker; Lenz, Bernd; Kornhuber, Johannes; Müller, Christian P. (Addiction Biology, 2017)
Alcohol use disorders are major psychiatric disorders. Correlational studies in humans suggested organizational hormonal effects during embryonic development as a risk factor for adult alcohol dependence. Permanent changes can be induced by the activity of sex hormones, like testosterone. Here, we demonstrate a relationship between prenatal androgen receptor (AR)-activation and adult alcohol as well as water drinking in mice in a sex-dependent fashion. Prenatal AR inhibition using the antagonist flutamide decreased adult male alcohol consumption. In contrast, prenatal AR activation by dihydrotestosterone (DHT) led to an increase in adult alcohol consumption in females. These effects were different in adult water drinking, flutamide increased water consumption in females and DHT increased water consumption in males. Prenatal flutamide reduced locomotion and anxiety in adult males but was ineffective in females. We found that prenatal AR activation controls adult levels of monoaminergic modulatory transmitters in the brain and blood hormone levels in a sex-specific way. RNA-Seq analysis confirmed a prenatal AR mediated control of adult expression of alcohol drinking-related genes like Bdnf and Per2. These findings demonstrate that prenatal androgen activity is a risk factor for the establishment of alcohol consumption in adults by its organizational effects.
EVALuna2:4035

Prevalence and stability of lysozyme in cheese - Schneider, Nadine; Werkmeister, Knut; Becker, Cord-Michael; Pischetsrieder, Monika (Food Chemistry, 2011)
The use of the preservative and potential allergen hen egg white lysozyme in cheese production has to be declared. In the present study, an HPLC method with fluorescence detection (HPLC-FLD) was optimised and validated for the analysis of lysozyme in cheese. Lysozyme was detected in concentrations between 30.8 and 386.2 mg/kg cheese in 30 out of 46 analysed commercial cheese samples. During cheese production and storage for 0-54 weeks a lysozyme satellite peak (LSP) was detected, which totals up to 18% of the lysozyme content. Mass spectrometry and peptide mass fingerprint revealed that LSP possesses the same primary structure as lysozyme. Since disulphide scrambling could not be detected, LSP was assigned to a conformational isomer of lysozyme. As a consequence, LSP was included in the HPLC-FLD analysis of lysozymes in cheese. © 2011 Elsevier Ltd. All rights reserved.
UnivIS-Import:2015-03-09:Pub.2011.nat.dchph.llmch.preval
Keywords: Cheese; Fluorescence detection; Hen egg white lysozyme; HPLC; Lysozyme degradation

Probing the potential of CnaB-type domains for the design of tag/catcher systems - Pröschel, Marlene; Kraner, Max; Horn, Anselm; Schäfer, Lena; Sonnewald, Uwe; Sticht, Heinrich (PLoS ONE, 2017)
Building proteins into larger, post-translational assemblies in a defined and stable way is still a challenging task. A promising approach relies on so-called tag/catcher systems that are fused to the proteins of interest and allow a durable linkage via covalent intermolecular bonds. Tags and catchers are generated by splitting protein domains that contain intramolecular isopeptide or ester bonds that form autocatalytically under physiological conditions. There are already numerous biotechnological and medical applications that demonstrate the usefulness of covalent linkages mediated by these systems. Additional covalent tag/catcher systems would allow creating more complex and ultra-stable protein architectures and networks. Two of the presently available tag/catcher systems were derived from closely related CnaB-domains of Streptococcus pyogenes and Streptococcus dysgalactiae proteins. However, it is unclear whether domain splitting is generally tolerated within the CnaBfamily or only by a small subset of these domains. To address this point, we have selected a set of four CnaB domains of low sequence similarity and characterized the resulting tag/catcher systems by computational and experimental methods. Experimental testing for intermolecular isopeptide bond formation demonstrated two of the four systems to be functional. For these two systems length and sequence variations of the peptide tags were investigated revealing only a relatively small effect on the efficiency of the reaction. Our study suggests that splitting into tag and catcher moieties is tolerated by a significant portion of the naturally occurring CnaB-domains, thus providing a large reservoir for the design of novel tag/catcher system

Probing the role of intercalating protein sidechains for kink formation in DNA - Sandmann, Achim; Sticht, Heinrich (PLoS ONE, 2018)
Protein binding can induce DNA kinks, which are for example important to enhance the specificity of the interaction and to facilitate the assembly of multi protein complexes. The respective proteins frequently exhibit amino acid sidechains that intercalate between the DNA base steps at the site of the kink. However, on a molecular level there is only little information available about the role of individual sidechains for kink formation. To unravel structural principles of protein-induced DNA kinking we have performed molecular dynamics (MD) simulations of five complexes that varied in their architecture, function, and identity of intercalated residues. Simulations were performed for the DNA complexes of wildtype proteins (Sac7d, Sox-4, CcpA, TFAM, TBP) and for mutants, in which the intercalating residues were individually or combined replaced by alanine. The work revealed that for systems with multiple intercalated residues, not all of them are necessarily required for kink formation. In some complexes (Sox-4, TBP), one of the residues proved to be essential for kink formation, whereas the second residue has only a very small effect on the magnitude of the kink. In other systems (e.g. Sac7d) each of the intercalated residues proved to be individually capable of conferring a strong kink suggesting a partially redundant role of the intercalating residues. Mutation of the key residues responsible for kinking either resulted in stable complexes with reduced kink angles or caused conformational instability as evidenced by a shift of the kink to an adjacent base step. Thus, MD simulations can help to identify the role of individual inserted residues for kinking, which is not readily apparent from an inspection of the static structures. This information might be helpful for understanding protein-DNA interactions in more detail and for designing proteins with altered DNA binding properties in the future.
EVALuna2:33714

Probing the Structure of the Escherichia coli Periplasmic Proteins HdeA and YmgD by Molecular Dynamics Simulations - Socher, Eileen; Sticht, Heinrich (Journal of Physical Chemistry B, 2016)
HdeA and YmgD are structurally homologous proteins in the periplasm of Escherichia coli. HdeA has been shown to represent an acid-activated chaperone, whereas the function of YmgD has not yet been characterized. We performed pH-titrating molecular dynamics simulations (pHtMD) to investigate the structural changes of both proteins and to assess whether YmgD may also exhibit an unfolding behavior similar to that of HdeA. The unfolding pathway of HdeA includes partially unfolded dimer structures, which represent a prerequisite for subsequent dissociation. In contrast to the coupled unfolding and dissociation of HdeA, YmgD displays dissociation of the folded subunits, and the subunits do not undergo significant unfolding even at low pH values. The differences in subunit stability between HdeA and YmgD may be explained by the structural features of helix D, which represents the starting point of unfolding in HdeA. In summary, the present study suggests that YmgD either is not an acid-activated chaperone or, at least, does not require unfolding for activation.
EVALuna2:26301

Profiling of gallbladder carcinoma reveals distinct miRNA profiles and activation of STAT1 by the tumor suppressive miRNA-145-5p - Goeppert, Benjamin; Truckenmueller, Felicia; Ori, Alessandro; Fritz, Valerie; Albrecht, Thomas; Fraas, Angelika; Scherer, Dominique; Silos, Rosa Gonzalez; Sticht, Carsten; Gretz, Norbert; Mehrabi, Arianeb; Bewerunge-Hudler, Melanie; et al. (Scientific Reports, 2019)
Gallbladder carcinoma (GBC) is a biliary tract cancer with few treatment options and poor prognosis. Radical surgery is the only potentially curative treatment option but most patients diagnosed with GBC are unresectable. Thus, there is a great need for the development of new treatment options including targeted therapy. Here, we aimed at identifying deregulated miRNAs and affected pathways involved in GBC development and progression. We performed global miRNA profiling of 40 GBC and 8 normal gallbladder tissues and identified large differences with 30% of miRNAs being differentially expressed (false discovery rate: FDR < 0.001). We found 24 miRNAs to be differentially regulated in GBC with poor outcome (p < 0.05) of which miR-145-5p was the most downregulated miRNA. Overexpression of miR-145-5p significantly reduced cell proliferation and colony formation. Gene expression analysis of cells expressing miR-145-5p mimics revealed activation of the Signal transducer and activator of transcription 1 (STAT1) signaling pathway which is mainly tumor suppressive. Furthermore, the activation of STAT1 by miR-145-5p was specifically observed in gallbladder carcinoma and cholangiocarcinoma but not in hepatocellular carcinoma cells. The Protein Tyrosine Phosphatase Receptor Type F (PTPRF) is downregulated upon miR-145 expression and may be involved in STAT1 regulation. In addition, we found that the STAT1-regulated protein IRF7 is downregulated in GBC compared to normal gallbladder tissue and low IRF7 expression is associated with significantly lower overall survival of GBC patients. Thus, this study identified GBC patient subgroups and provides new mechanistic insights in the tumor suppressive function of miR-145-5p leading to activation of STAT1 signaling.
CRIS-Team WoS Importer:2019-03-29

Programming of neural progenitors of the adult subependymal zone towards a glutamatergic neuron lineage by neurogenin 2 - Péron, Sophie; Miyakoshi, Leo M.; Brill, Monika S.; Manzano-Franco, Diana; Serrano-López, Julia; Fan, Wenqiang; Marichal, Nicolás; Ghanem, Alexander; Conzelmann, Karl Klaus; Karow, Marisa; Ortega, Felipe; Gascón, Sergio; et al. (Stem Cell Reports, 2023)
Although adult subependymal zone (SEZ) neural stem cells mostly generate GABAergic interneurons, a small progenitor population expresses the proneural gene Neurog2 and produces glutamatergic neurons. Here, we determined whether Neurog2 could respecify SEZ neural stem cells and their progeny toward a glutamatergic fate. Retrovirus-mediated expression of Neurog2 induced the glutamatergic lineage markers TBR2 and TBR1 in cultured SEZ progenitors, which differentiated into functional glutamatergic neurons. Likewise, Neurog2-transduced SEZ progenitors acquired glutamatergic neuron hallmarks in vivo. Intriguingly, they failed to migrate toward the olfactory bulb and instead differentiated within the SEZ or the adjacent striatum, where they received connections from local neurons, as indicated by rabies virus-mediated monosynaptic tracing. In contrast, lentivirus-mediated expression of Neurog2 failed to reprogram early SEZ neurons, which maintained GABAergic identity and migrated to the olfactory bulb. Our data show that NEUROG2 can program SEZ progenitors toward a glutamatergic identity but fails to reprogram their neuronal progeny.
CRIS-Team Scopus Importer:2023-12-15
Keywords: adult neurogenesis; adult subventricular zone; fate reprogramming; neural specification; neural stem cell; neurogenin 2; olfactory bulb; proneural gene

Progress towards a "next generation" NDDO-based semiempirical technique. - Clark, Timothy; Winget, Paul; Horn, Anselm; Martin, Bodo; et al. (ACS National Meeting Book of Abstracts, 2002)

Prolonged glial expression of Sox4 in the central nervous system leads to architectural cerebellar defects and ataxia. - Sock, Elisabeth; Wegner, Michael; et al. (The Journal of Neuroscience, 2007)
UnivIS-Import:2015-03-09:Pub.2007.med.IB.LPCIPDBI.prolon

Properties of Oligomeric Interaction of the Cytomegalovirus Core Nuclear Egress Complex (NEC) and Its Sensitivity to an NEC Inhibitory Small Molecule - Kicuntod, Jintawee; Alkhashrom, Sewar; Häge, Sigrun; Diewald, Benedikt; Müller, Regina; Hahn, Friedrich; Lischka, Peter; Sticht, Heinrich; Eichler, Jutta; Marschall, Manfred (Viruses, 2021)
Herpesviral nuclear egress is a regulated process shared by all family members, ensuring the efficient cytoplasmic release of viral capsids. In the case of human cytomegalovirus (HCMV), the core of the nuclear egress complex (NEC) consists of the pUL50-pUL53 heterodimer that builds hexameric lattices for capsid binding and multicomponent interaction, including NEC-associated host factors. A characteristic feature of NEC interaction is the N-terminal hook structure of pUL53 that binds to an alpha-helical groove of pUL50, thus termed as hook-into-groove interaction. This central regulatory element is essential for viral replication and shows structural-functional conservation, which has been postulated as a next-generation target of antiviral strategies. However, a solid validation of this concept has been missing. In the present study, we focused on the properties of oligomeric HCMV core NEC interaction and the antiviral activity of specifically targeted prototype inhibitors. Our data suggest the following: (i) transiently expressed, variably tagged versions of HCMV NEC proteins exert hook-into-groove complexes, putatively in oligomeric assemblies that are distinguishable from heterodimers, as shown by in vitro assembly and coimmunoprecipitation approaches; (ii) this postulated oligomeric binding pattern was further supported by the use of a pUL50::pUL53 fusion construct also showing a pronounced multi-interaction potency; (iii) using confocal imaging cellular NEC-associated proteins were found partly colocalized with the tagged core NECs; (iv) a small inhibitory molecule, recently identified by an in vitro binding inhibition assay, was likewise active in blocking pUL50-pUL53 oligomeric assembly and in exerting antiviral activity in HCMV-infected fibroblasts. In summary, the findings refine the previous concept of HCMV core NEC formation and nominate this drug-accessible complex as a validated antiviral drug target.
CRIS-Team WoS Importer:2021-04-09

Prosequence switching: an effective strategy to produce biologically active E. coli heat-stable enterotoxin STh - Weiglmeier, Philipp R.; Berkner, Hanna; Seebahn, Angela; Vogel, Nicolas; Schreiber, Rainer; Woehrl, Birgitta M.; Schwarzinger, Stephan; Roesch, Paul (Journal of Biomolecular Structure & Dynamics, 2014)
Enterotoxigenic Escherichia coli (ETEC) infections account for the majority of cases of acute secretory diarrhea. The causative agents are enterotoxins secreted by ETEC, among them is the heat-stable enterotoxin, STh. STh is a 19-amino acid peptide containing three disulfide bonds that stimulates fluid secretion in the bowel by binding to the receptor domain of intestinal guanylyl cyclase C (GC-C). Since GC-C agonists have pharmacologic potential for diagnosis and treatment of disorders such as constipation-predominant irritable bowel syndrome (IBS-C), chronic constipation, and colorectal carcinoma, it is crucial to develop methods for the large-scale production of STh and related peptides. Here, we present a strategy for recombinant expression of STh that relies on the use of the prosequence of human uroguanylin to support proper folding and disulfide bond formation. The chimeric protein CysCys-STh consisting of the propeptide of uroguanylin as N-terminus and the STh peptide as C-terminus was expressed in E. coli, and an efficient purification protocol was developed. Trypsin digestion of this protein released the enterotoxin which could be obtained in high purity. NMR and mass spectrometry confirmed the identity and homogeneity of the toxin, and its biological activity was confirmed by a cell-based in vivo assay. The expression scheme introduced here represents a cost-efficient and scalable way of STh production.
EVALuna2:4705

Prospero-related homeobox 1 gene (Prox1) is regulated by canonical Wnt signaling and has a stage-specific role in adult hippocampal neurogenesis - Karalay, Oezlem; Doberauer, Kathrin; Vadodaria, Krishna C.; Knobloch, Marlen; Berti, Lucia; Miquelajauregui, Amaya; Schwark, Manuela; Jagasia, Ravi; Taketo, Makoto M.; Tarabykin, Victor; Lie, Dieter Chichung; Jessberger, Sebastian (Proceedings of the National Academy of Sciences of the United States of America, 2011)
Neural stem cells (NSCs) generate new granule cells throughout life in the mammalian hippocampus. Canonical Wnt signaling regulates the differentiation of NSCs towards the neuronal lineage. Here we identified the prospero-related homeodomain transcription factor Prox1 as a target of ?-catenin-TCF/LEF signaling in vitro and in vivo. Prox1 overexpression enhanced neuronal differentiation whereas shRNA-mediated knockdown of Prox1 impaired the generation of neurons in vitro and within the hippocampal niche. In contrast, Prox1 was not required for survival of adult-generated granule cells after they had matured, suggesting a role for Prox1 in initial granule cell differentiation but not in the maintenance of mature granule cells. The data presented here characterize a molecular pathway from Wnt signaling to a transcriptional target leading to granule cell differentiation within the adult brain and identify a stage-specific function for Prox1 in the process of adult neurogenesis.
EVALuna2:26323

Protective capacity of neutralizing and non-neutralizing antibodies against glycoprotein B of cytomegalovirus - Bootz, Anna; Karbach, Astrid; Spindler, Johannes; Kropff, Barbara; Reuter, Nina; Sticht, Heinrich; Winkler, Thomas; Britt, William J.; Mach, Michael (PLoS Pathogens, 2017)
Human cytomegalovirus (HCMV) is an important, ubiquitous pathogen that causes severe clinical disease in immunocompromised individuals, such as organ transplant recipients and infants infected in utero. Antiviral chemotherapy remains problematic due to toxicity of the available compounds and the emergence of viruses resistant to available antiviral therapies. Antiviral antibodies could represent a valuable alternative strategy to limit the clinical consequences of viral disease in patients. The envelope glycoprotein B (gB) of HCMV is a major antigen for the induction of virus neutralizing antibodies. However, the role of anti-gB antibodies in the course of the infection in-vivo remains unknown. We have used a murine CMV (MCMV) model to generate and study a number of anti-gB monoclonal antibodies (mAbs) with differing virus-neutralizing capacities. The mAbs were found to bind to similar antigenic structures on MCMV gB that are represented in HCMV gB. When mAbs were used in immunodeficient RAG-/- hosts to limit an ongoing infection we observed a reduction in viral load both with mAbs having potent neutralizing capacity in-vitro as well as mAbs classified as non-neutralizing. In a therapeutic setting, neutralizing mAbs showed a greater capacity to reduce the viral burden compared to non-neutralizing antibodies. Efficacy was correlated with sustained concentration of virus neutralizing mAbs in-vivo rather than their in-vitro neutralizing capacity. Combinations of neutralizing mAbs further augmented the antiviral effect and were found to be as potent in protection as polyvalent serum from immune animals. Prophylactic administration of mAbs before infection was also protective and both neutralizing and non-neutralizing mAbs were equally effective in preventing lethal infection of immunodeficient mice. In summary, our data argue that therapeutic application of potently neutralizing mAbs against gB represent a strategy to modify the outcome of CMV infection in immunodeficient hosts. When present before infection, both neutralizing and non-neutralizing anti-gB exhibited protective capacity.
EVALuna2:33722

Protein kinase CK2 interacts at the neuromuscular synapse with Rapsyn, Rac1, 14-3-3?, and Dok-7 proteins and phosphorylates the latter two - Herrmann, Dustin; Straubinger, Marion; Hashemolhosseini, Said (Journal of Biological Chemistry, 2015)
Previously, we demonstrated that the protein kinase CK2 associates with and phosphorylates the receptor tyrosine kinase MuSK (muscle specific receptor tyrosine kinase) at the neuromuscular junction (NMJ), thereby preventing fragmentation of the NMJs (Cheusova, T., Khan, M. A., Schubert, S. W., Gavin, A. C., Buchou, T., Jacob, G., Sticht, H., Allende, J., Boldyreff, B., Brenner, H. R., and Hashemolhosseini, S. (2006) Genes Dev. 20, 1800-1816). Here, we asked whether CK2 interacts with other proteins involved in processes at the NMJ, which would be consistent with the previous observation that CK2 appears enriched at the NMJ. We identified the following proteins to interact with protein kinase CK2: (a) the ? and ? subunits of the nicotinic acetylcholine receptors with weak interaction, (b) dishevelled (Dsh), and (c) another four proteins, Rapsyn, Rac1, 14-3-3?, and Dok-7, with strong interaction. CK2 phosphorylated 14-3-3? at serine residue 235 and Dok-7 at several serine residues but does not phosphorylate Rapsyn or Rac1. Furthermore, phosphomimetic Dok-7 mutants aggregated nicotinic acetylcholine receptors in C2C12 myotubes with significantly higher frequency than wild type Dok-7. Additionally, we mapped the interacting epitopes of all four binding partners to CK2 and thereby gained insights into the potential role of the CK2/Rapsyn interaction.
EVALuna2:4975

Protein stability and domain topology determine the transcriptional activity of the mammalian glial cells missing homolog, GCMb - Wegner, Michael; et al. (Journal of Biological Chemistry, 2000)
The glial cells missing (GCM) family of transcription factors consists of Drosophila GCM and the mammalian proteins GCMa and GCMb. They are expressed in a highly restricted manner during development and are known or assumed to be important regulators of developmental fate decisions. As the biochemical properties of GCMb have not been studied so far, we have undertaken a detailed structure-function analysis of the mouse GCMb (mGCMb) protein. DNA-binding specificity was very similar to that of other GCM proteins. Nevertheless, mGCMb was only a weak transcriptional activator in a number of different tissue culture systems. Interestingly, this was not due to an intrinsic absence of transactivation potential. In effect, we were able to identify two separate transactivation domains within mGCMb, one carboxyl- terminally adjacent to the DNA-binding domain and the second within the extreme carboxyl terminus. Activity of both transactivation domains was, however, modulated by an inhibitory region unique to mGCMb and located between the two transactivation domains. Furthermore, pulse-chase experiments proved that the mGCMb protein has a half-life approximately four times shorter than mGCMa. Introduction of the above mentioned inhibitory domain of mGCMb into mGCMa shortened the half-life of mGCMa to a value typical of mGCMb with a concomitant reduction in transactivation potential. Given the strong correlation between protein stability and transactivation potential, functional differences between the two mammalian GCM homologs are likely due to differences in stability with a single inhibitory region in mGCMb being involved in the reduction of both.
UnivIS-Import:2015-03-05:Pub.2000.med.IB.LPCIPDBI.protei_18

Protein zero Gene expression is regulated by the glial transcription factor Sox10 - Wegner, Michael; et al. (Molecular and Cellular Biology, 2000)
Myelinating glia express high levels of a unique set of genes which code for structural proteins of the myelin sheath. Few transcription factors have so far been implicated in the regulation of any myelin gene. Here we show that the protein zero (P0) gene, a myelin gene exclusively expressed in the Schwann cell lineage of the peripheral nervous system, is controlled in its expression by the high-mobility-group domain protein Sox10 both in tissue culture and in vivo. Induction of wild-type Sox10, but not of other transcription factors or Sox10 mutants, strongly increased endogenous P0 expression in tissue culture. This activation was mediated by the P0 promoter, which was stimulated by Sox10 in transient transfections. Detailed analyses revealed the involvement of a proximal and a distal promoter region. The distal region functioned only in conjunction with the proximal one and contained a single Sox consensus binding site, which accounted for most of its activity. In contrast, the proximal region mediated Sox10 responsiveness on its own. It contained multiple binding sites for Sox proteins, with two high-affinity sites being the most significant. P0 expression also depended on Sox10 in vivo, as evident from the analysis of Schwann cell precursors in mouse embryos with Sox10 mutation at day 12.5 of embryogenesis. To our knowledge this is the most conclusive link to date between a glial transcription factor and cell-specific activation of myelin gene expression.
UnivIS-Import:2015-03-05:Pub.2000.med.IB.LPCIPDBI.protei

Proteomic analysis of the multimeric nuclear egress complex of human cytomegalovirus - Milbradt, Jens; Kraut, Alexandra; Hutterer, Corina; Sonntag, Ellen; Schmeiser, Cathrin; Ferro, Myriam; Wagner, Sabrina; Lenac, Tihana; Claus, Claudia; Pinkert, Sandra; Hamilton, Stuart T.; Rawlinson, William D.; et al. (Molecular & Cellular Proteomics, 2014)
Herpesviral capsids are assembled in the host cell nucleus before being translocated into the cytoplasm for further maturation. The crossing of the nuclear envelope represents a major event that requires the formation of the nuclear egress complex (NEC). Previous studies demonstrated that human cytomegalovirus (HCMV) proteins pUL50 and pUL53, as well as their homologs in all members of Herpesviridae, interact with each other at the nuclear envelope and form the heterodimeric core of the NEC. In order to characterize further the viral and cellular protein content of the multimeric NEC, the native complex was isolated from HCMV-infected human primary fibroblasts at various time points and analyzed using quantitative proteomics. Previously postulated components of the HCMV-specific NEC, as well as novel potential NEC-associated proteins such as emerin, were identified. In this regard, interaction and colocalization between emerin and pUL50 were confirmed by coimmunoprecipitation and confocal microscopy analyses, respectively. A functional validation of viral and cellular NEC constituents was achieved through siRNA-mediated knockdown experiments. The important role of emerin in NEC functionality was demonstrated by a reduction of viral replication when emerin expression was down-regulated. Moreover, under such conditions, reduced production of viral proteins and deregulation of viral late cytoplasmic maturation were observed. Combined, these data prove the functional importance of emerin as an NEC component, associated with pUL50, pUL53, pUL97, p32/gC1qR, and further regulatory proteins. Summarized, our findings provide the first proteomics-based characterization and functional validation of the HCMV-specific multimeric NEC.
EVALuna2:8226

Proteomic interaction patterns between human cyclins, the cyclin-dependent kinase ortholog pUL97 and additional cytomegalovirus proteins - Steingruber, Mirjam; Kraut, Alexandra; Socher, Eileen; Sticht, Heinrich; Reichel, Anna; Stamminger, Thomas; Amin, Bushra; Coute, Yohann; Hutterer, Corina; Marschall, Manfred (Viruses, 2016)
The human cytomegalovirus (HCMV)-encoded cyclin-dependent kinase (CDK) ortholog pUL97 associates with human cyclin B1 and other types of cyclins. Here, the question was addressed whether cyclin interaction of pUL97 and additional viral proteins is detectable by mass spectrometry-based approaches. Proteomic data were validated by coimmunoprecipitation (CoIP), Western blot, in vitro kinase and bioinformatic analyses. Our findings suggest that: (i) pUL97 shows differential affinities to human cyclins; (ii) pUL97 inhibitor maribavir (MBV) disrupts the interaction with cyclin B1, but not with other cyclin types; (iii) cyclin H is identified as a new high-affinity interactor of pUL97 in HCMV-infected cells; (iv) even more viral phosphoproteins, including all known substrates of pUL97, are detectable in the cyclin-associated complexes; and (v) a first functional validation of pUL97-cyclin B1 interaction, analyzed by in vitro kinase assay, points to a cyclin-mediated modulation of pUL97 substrate preference. In addition, our bioinformatic analyses suggest individual, cyclin-specific binding interfaces for pUL97-cyclin interaction, which could explain the different strengths of interactions and the selective inhibitory effect of MBV on pUL97-cyclin B1 interaction. Combined, the detection of cyclin-associated proteins in HCMV-infected cells suggests a complex pattern of substrate phosphorylation and a role of cyclins in the fine-modulation of pUL97 activities.
Keywords: CDK ortholog pUL97; Cyclin-associated protein complexes; Human cyclins; Human cytomegalovirus; Molecular modeling; Proteomic analysis

Publisher Correction: Nfat/calcineurin signaling promotes oligodendrocyte differentiation and myelination by transcription factor network tuning - Weider, Matthias; Starost, Laura Julia; Groll, Katharina; Küspert, Melanie; Sock, Elisabeth; Wedel, Miriam; Fröb, Franziska; Schmitt, Christian; Baroti, Tina; Hartwig, Anna; Hillgärtner, Simone; Piefke, Sandra; et al. (Nature Communications, 2018)
The originally published version of this Article omitted Tanja Kuhlmann and Michael Wegner as jointly supervising authors. This has now been corrected in both the PDF and HTML versions of the Article.
EVALuna2:35744

Qualitative Determination of Specific Protein Glycation Products by Matrix-Assisted Laser Desorption/Ionization Mass Spectrometry Peptide Mapping - Humeny, Andreas; Kislinger, Thomas; Becker, Cord-Michael; Pischetsrieder, Monika (Journal of Agricultural and Food Chemistry, 2002)
The nonenzymatic reaction between reducing sugars and proteins, known as the Maillard reaction, has received increased recognition from nutritional science and medical research. The development of new analytical techniques for the detection of protein-bound Maillard products is therefore crucial. In this study, we applied peptide mapping by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry to investigate the formation of structurally specific Maillard products on glycated lysozyme (AGE-lysozyme), produced upon incubation with D-glucose. In parallel, we synthesized Nε-(carboxymethyl)lysine-modified lysozyme (CML-lysozyme) and Nε-(carboxyethyl)lysine-modified lysozyme, two well-described glycation products, as model substances. 3-Deoxyglucosone-modified lysozyme and methylglyoxal-modified lysozyme were prepared as examples of glycation products incubated with dicarbonyl compounds. We were able to detect specific modifications on AGE-lysozyme, which were assigned to CML, imidazolone A, and the Amadori product.
UnivIS-Import:2015-03-09:Pub.2002.nat.dchph.llmch.qualit
Keywords: Imidazolone A; Maillard reaction; MALDI-TOF-MS peptide mapping; N; Protein glycation

Qualitative Determination of the Early Maillard-Products by MALDITOF Mass Spectrometry Peptide Mapping - Kislinger, Thomas; Humeny, Andreas; Seeber, Silke; Peich, Carlo; Becker, Cord-Michael; Pischetsrieder, Monika (European Food Research and Technology, 2002)
Matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS) was used to qualitatively study the formation of early Maillard products of lysozyme, produced upon incubation with seven different sugars (D-ribose, L-rhamnose, D-glucose, D-fructose, D-galactose, D-lactose, D-maltose) in solution, in the presence of oxygen. MALDI-TOF mass spectra of intact lysozyme revealed a heterogeneous distribution of glycation products, detected by significant mass increase and peak broadening. Therefore, to get more detailed information about the nature of the glycation products, we performed MALDI-TOF MS peptide mapping analysis. In each of the peptide mapping spectra we were able to detect the early glycation products (Amadori products/glucosylamines) with high selectivity. We were able to distinguish between the Amadori products of the different sugars, due to the characteristic mass increases of the glycated peptides. Furthermore, variations of the modification pattern were observed, very likely due to the different relativities of the seven reducing sugars. Other, more advanced glycation products of the initially formed Maillard products were also detected. Further studies regarding the nature of these late Maillard products are in progress. Here we report, for the first time, the use of MALDI-TOF MS peptide mapping as a quick and highly selective method for the detection of early stage Maillard products produced upon incubation of lysozyme with seven different reducing sugars.
UnivIS-Import:2015-03-09:Pub.2002.nat.dchph.llmch.qualit_2
Keywords: Maillard reaction; Amadori products; MALDI-TOF MS peptide mapping

Quantification of dsDNA functionalization efficiency in THz biosensors - Weisenstein, C.; Schmeck, M.; Schaar, Dominik; Wigger, A. K.; Boßerhoff, Anja Katrin; Bolivar, P. Haring (International Conference on Infrared, Millimeter, and Terahertz Waves, IRMMW-THz, 2019)
In the past, THz bioanalytical techniques have been proven to be viable tools for label-free detection of biomolecules. However, significant improvements in the detection limit are needed to apply THz biosensors in biomedical diagnosis. To determine detection limits of the biosensor and the absolute amount of sample volume, quantitative measurements are required. We present label-free THz sensing of dsDNA and implement an approach based on reference investigations to quantify the dsDNA functionalization density. Defined functionalization densities are vital to maximize the adsorption of a dsDNA groove-binding protein, which acts as a tumor marker for malignant melanoma.
CRIS-Team Scopus Importer:2019-11-19

Quantitative assessment of glial cells in the human and guinea pig enteric nervous system with an anti-Sox8/9/10 antibody. - Wegner, Michael; et al. (Journal of Comparative Neurology, 2008)
Quantitative changes of enteric glia (EGC) have been implicated in gastrointestinal disorders. To facilitate future studies of EGC in human pathology, we aimed to characterize thoroughly glial markers in the human enteric nervous system (ENS) and to compare EGC in man and guinea pig. Whole-mount preparations of the enteric nerve plexuses from human and guinea pig ileum and colon were labeled with antibodies against S100b, glial fibrillary acidic protein (GFAP), and p75NGFR and the transcription factors Sox8/9/10 and neuronally counterstained. Abundant immunoreactivity (IR) for S100b, GFAP, p75NGFR, and Sox8/9/10 was detected in EGC of all studied regions. Although the cytoplasmatic staining pattern of most markers did not permit glial quantification, the nuclear localization of Sox8/9/10-IR allowed to identify and count all EGC individually. In both man and guinea pig, myenteric ganglia were larger and contained more EGC and neurons than submucous ganglia. Furthermore, there were more EGC in the human than in the guinea pig myenteric plexus (MP), glial density was consistently higher in the human ENS, and the glia index (glia:neuron ratio) ranged from 1.3 to 1.9 and from 5.9 to 7.0 in the human submucous plexus (SMP) and MP, respectively, whereas, in guinea pig, the glia index was 0.8-1.0 in the SMP and 1.7 in the MP. The glia index was the most robust quantitative descriptor within one species. This is a comprehensive set of quantitative EGC measures in man and guinea pig that provides a basis for pathological assessment of glial proliferation and/or degeneration in the diseased gut. © 2008 Wiley-Liss, Inc.
UnivIS-Import:2015-03-09:Pub.2008.med.IB.LPCIPDBI.quanti
Keywords: Enteric glial cells; Enteric nervous system; Glia index; Human pathology; Morphometry; Myenteric plexus; Submucous plexus

Quantitative detection of disseminated melanoma cells by trp-1 transcript analysis reveals stochastic distribution of pulmonary metastases - Kyjacova, Lenka; Saup, Rafael; Rothley, Melanie; Schmaus, Anja; Wagner, Tabea; Boßerhoff, Anja Katrin; Garvalov, Boyan K.; Thiele, Wilko; Sleeman, Jonathan P. (Journal of Clinical Medicine, 2021)
A better understanding of the process of melanoma metastasis is required to underpin the development of novel therapies that will improve patient outcomes. The use of appropriate animal models is indispensable for investigating the mechanisms of melanoma metastasis. However, reliable and practicable quantification of metastases in experimental mice remains a challenge, particularly if the metastatic burden is low. Here, we describe a qRT-PCR-based protocol that employs the melanocytic marker Trp-1 for the sensitive quantification of melanoma metastases in the murine lung. Using this protocol, we were able to detect the presence of as few as 100 disseminated melanoma cells in lung tissue. This allowed us to quantify metastatic burden in a spontaneous syngeneic B16-F10 metastasis model, even in the absence of visible metastases, as well as in the autochthonous Tg(Grm1)/Cyld−/− melanoma model. Importantly, we also observed an uneven distribution of disseminated melanoma cells amongst the five lobes of the murine lung, which varied considerably from animal to animal. Together, our findings demonstrate that the qRT-PCR-based detection of Trp-1 allows the quantification of low pulmonary metastatic burden in both transplantable and autochthonous murine melanoma models, and show that the analysis of lung metastasis in such models needs to take into account the stochastic distribution of metastatic lesions amongst the lung lobes.
CRIS-Team Scopus Importer:2021-12-03
Keywords: Animal models; Lung; Melanoma; Metastasis; Mice; Trp-1

Quantitative methods to study epithelial morphogenesis and polarity - Sagner, Andreas; Aigouy, B.; Collinet, Claudio; Merkel, Matthias; Sagner, Andreas (Methods in Cell Biology, 2017)
Keywords: Polarity; Quantitative biology; Morphogenesis; Multiscale analysis; Tissue deformation; Cells; Genetic mosaics; Epithelia; Microscopy; Image processing

Quantum mechanical/molecular mechanical (QM/MM) docking: an evaluation for known test systems - Beierlein, Frank; Lanig, Harald; Schürer, Gudrun; Horn, Anselm; Clark, Timothy (Molecular Physics, 2003)
A combined quantum mechanical/molecular mechanical (QM/MM) docking approach for the investigation of protein-inhibitor complexes is presented. Starting points for QM/MM optimizations are generated with AutoDock. The subsequent semiempirical AM1 QM/MM optimization of the complex obtained by the docking procedure gives a more detailed description of the binding mode and the electronic properties of the ligand. As we use a flexible protein environment in the QM/MM optimizations, we are able to simulate limited structural changes of the enzyme upon binding a ligand, even within a simple geometry optimization. The method was validated using a set of structurally known protein-inhibitor complexes, whose crystallographic data were taken from the Protein Data Bank. In addition to protein structures taken directly from complexes with the inhibitors, structures of uncomplexed HIV-1-protease and thrombin were also used successfully for QM/MM docking experiments. By comparing the resulting structures with those obtained using protein structures from protein-inhibitor complexes, we find that the method is able to simulate the effect of the induced fit when a simple optimization is adequate to reproduce the protein movement. Describing the ligand quantum mechanically gives a detailed view of its electronic properties, for example its polarization within the active site of the enzyme. This study suggests strongly that a QM/MM molecular dynamics approach will be able to simulate the induced fit in general cases.

Quantum mechanical/molecular mechanical (QM/MM) docking: A new protocol and its evaluation for known test systems. - Horn, Anselm; Beierlein, Frank; Lanig, Harald; Schürer, Gudrun; Clark, Timothy (2004)

Radial glia phagocytose axonal debris from degenerating overextending axons in the developing olfactory bulb - Amaya, Daniel A.; Wegner, Michael; Stolt, Claus; Chehrehasa, Fatemeh; Ekberg, Jenny A. K.; St John, James A. (Journal of Comparative Neurology, 2015)
Axon targeting during the development of the olfactory system is not always accurate, and numerous axons overextend past the target layer into the deeper layers of the olfactory bulb. To date, the fate of the mis-targeted axons has not been determined. We hypothesized that following overextension, the axons degenerate, and cells within the deeper layers of the olfactory bulb phagocytose the axonal debris. We utilized a line of transgenic mice that expresses ZsGreen fluorescent protein in primary olfactory axons. We found that overextending axons closely followed the filaments of radial glia present in the olfactory bulb during embryonic development. Following overextension into deeper layers of the olfactory bulb, axons degenerated and radial glia responded by phagocytosing the resulting debris. We used in vitro analysis to confirm that the radial glia had phagocytosed debris from olfactory axons. We also investigated whether the fate of overextending axons was altered when the development of the olfactory bulb was perturbed. In mice that lacked Sox10, a transcription factor essential for normal olfactory bulb development, we observed a disruption to the morphology and positioning of radial glia and an accumulation of olfactory axon debris within the bulb. Our results demonstrate that during early development of the olfactory system, radial glia play an important role in removing overextended axons from the deeper layers of the olfactory bulb.
EVALuna2:4966

RanBPM is expressed in synaptic layers of the mammalian retina and binds to metabotropic glutamate receptors. - Seebahn, Angela; Rose, Melanie; Enz, Ralf (FEBS letters, 2008)
In the central nervous system, synaptic signal transduction depends on the regulation of neurotransmitter receptors by interacting proteins. Here, we searched for proteins interacting with two metabotropic glutamate receptor type 8 isoforms (mGlu8a and mGlu8b) and identified RanBPM. RanBPM is expressed in several brain regions, including the retina. There, RanBPM is restricted to the inner plexiform layer where it co-localizes with the mGlu8b isoform and processes of cholinergic amacrine cells expressing mGlu2 receptors. RanBPM interacts with mGlu2 and other group II and group III receptors, except mGlu6. Our data suggest that RanBPM might be associated with mGlu receptors at synaptic sites. © 2008 Federation of European Biochemical Societies.
UnivIS-Import:2017-12-18:Pub.2008.med.IB.profes_1.ranbpm
Keywords: mGlu2; mGlu8b; Protein interaction; RanBP9; RanBPM; Retina

Rare frameshift mutation in SERPINA3 contributes to generalized pustular psoriasis - Hüffmeier, Ulrike; Sticht, Heinrich; Wenzel, J.; Wilsmann-Theis, D.; Wolff, K.; Löhr, Sabine; Frey, Benjamin; Hahn, M.; Ekici, Arif Bülent; Uebe, S.; Thiel, Christian; Wiesmann da Silva Reis, André; et al. (EUROPEAN JOURNAL OF HUMAN GENETICS, 2019)
CRIS-Team WoS Importer:2019-10-25

Rare Loss-of-Function Mutation in SERPINA3 in Generalized Pustular Psoriasis - Frey, Silke; Sticht, Heinrich; Wilsmann-Theis, Dagmar; Gerschütz, Anne; Wolf, Katharina; Löhr, Sabine; Haskamp, Stefan; Frey, Benjamin; Hahn, Madelaine; Ekici, Arif Bülent; Uebe, Steffen; Thiel, Christian; et al. (Journal of Investigative Dermatology, 2020)
CRIS-Team Scopus Importer:2020-03-06

Rare slow channel congenital myasthenic syndromes without repetitive compound muscle action potential and dramatic response to low dose fluoxetine - Durmus, Hacer; Sticht, Heinrich; Ceylaner, Serdar; Hashemolhosseini, Said; Deymeer, Feza (Acta Neurologica Belgica, 2020)
Congenital myasthenic syndromes are rare hereditary disorders caused by mutations associated with proteins of the neuromuscular junction. Abnormal ‘‘gain of function’’ mutations result in prolonged nicotinic acetylcholine receptor channel open state causing a rare subtype of CMS, slow-channel CMS (SCCMS). Mutations in the delta subunit encoding the gene, CHRND, resulting in SCCMS are extremely rare. An important clue to the diagnosis of SCCMS is repetitive CMAP’s. Fluoxetine, usually at high doses, is used to treat SCCMS. The mutation, recently described in one patient, was identified by whole exome sequencing and validated, and its segregation with the disease was ascertained by Sanger sequencing. Here, we describe clinical and genetic findings of an early onset SCCMS patient carrying a very rare missense mutation c.880C > T in CHRND causing a highly conserved leucine to phenylalanine substitution in the M2 domain of CHRND. The patient had no repetitive CMAP. He had a dramatic response to fluoxetine at low–moderate doses (40 mg/day), increasing over months: Being wheelchair bound, he could walk independently after treatment. Rare cases may offer insight into the pathological gating mechanism leading to CMS. SCCMS should be suspected even without a repetitive CMAP. Fluoxetine at relatively low doses can be a very effective treatment.
CRIS-Team Scopus Importer:2020-10-16
Keywords: AChR delta subunit; CHRND; Congenital myasthenic syndromes; Fluoxetine; Slow channel

Rational design of ?-sheet ligands against A?42-induced toxicity - Hochdoerffer, Katrin; Maerz-Berberich, Julia; Nage-Steger, Luitgard; Epple, Matthias; Meyer-Zaika, Wolfgang; Horn, Anselm; Sticht, Heinrich; Sinha, Sharmistha; Bitan, Gal; Schrader, Thomas (Journal of the American Chemical Society, 2011)
A ?-sheet-binding scaffold was equipped with long-range chemical groups for tertiary contacts toward specific regions of the Alzheimer's A? fibril. The new constructs contain a trimeric aminopyrazole carboxylic acid, elongated with a C-terminal binding site, whose influence on the aggregation behavior of the A?(42) peptide was studied. MD simulations after trimer docking to the anchor point (F19/F20) suggest distinct groups of complex structures each of which featured additional specific interactions with characteristic A? regions. Members of each group also displayed a characteristic pattern in their antiaggregational behavior toward A?. Specifically, remote lipophilic moieties such as a dodecyl, cyclohexyl, or LPFFD fragment can form dispersive interactions with the nonpolar cluster of amino acids between I31 and V36. They were shown to strongly reduce Thioflavine T (ThT) fluorescence and protect cells from A? lesions (MTT viability assays). Surprisingly, very thick fibrils and a high ?-sheet content were detected in transmission electron microscopy (TEM) and CD spectroscopic experiments. On the other hand, distant single or multiple lysines which interact with the ladder of stacked E22 residues found in A? fibrils completely dissolve existing ?-sheets (ThT, CD) and lead to unstructured, nontoxic material (TEM, MTT). Finally, the triethyleneglycol spacer between heterocyclic ?-sheet ligand and appendix was found to play an active role in destabilizing the turn of the U-shaped protofilament. Fluorescence correlation spectroscopy (FCS) and sedimentation velocity analysis (SVA) provided experimental evidence for some smaller benign aggregates of very thin, delicate structure (TEM, MTT). A detailed investigation by dynamic light scattering (DLS) and other methods proved that none of the new ligands acts as a colloid. The evolving picture for the disaggregation mechanism by these new hybrid ligands implies transformation of well-ordered fibrils into less structured aggregates with a high molecular weight. In the few cases where fibrillar components remain, these display a significantly altered morphology and have lost their acute cellular toxicity.
EVALuna2:26270

Recent advances in practical methods for liver cell biology: A short overview - Torres, Sandra; Abdullah, Zeinab; Brol, Maximilian J.; Hellerbrand, Claus; Fernandez, Mercedes; Fiorotto, Romina; Klein, Sabine; Königshofer, Philipp; Liedtke, Christian; Lotersztajn, Sophie; Nevzorova, Yulia A.; Schierwagen, Robert; et al. (International Journal of Molecular Sciences, 2020)
Molecular and cellular research modalities for the study of liver pathologies have been tremendously improved over the recent decades. Advanced technologies offer novel opportunities to establish cell isolation techniques with excellent purity, paving the path for 2D and 3D microscopy and high-throughput assays (e.g., bulk or single-cell RNA sequencing). The use of stem cell and organoid research will help to decipher the pathophysiology of liver diseases and the interaction between various parenchymal and non-parenchymal liver cells. Furthermore, sophisticated animal models of liver disease allow for the in vivo assessment of fibrogenesis, portal hypertension and hepatocellular carcinoma (HCC) and for the preclinical testing of therapeutic strategies. The purpose of this review is to portray in detail novel in vitro and in vivo methods for the study of liver cell biology that had been presented at the workshop of the 8th meeting of the European Club for Liver Cell Biology (ECLCB-8) in October of 2018 in Bonn, Germany.
CRIS-Team Scopus Importer:2020-03-31
Keywords: Fibrogenesis; Hepatic stellate cells; Hepatocellular cancer; In vitro models; Steatosis

Recovery of a dilated left ventricle after cessation of cocaine and HVAD (TM) explanation using a titanium plug - Elbayomi, Mohamed; Weyand, Michael; Seitz, Tatjana; Heim, Christian; Steger, Katrin; Tandler, Rene (Journal of Cardiac Surgery, 2022)
The ultimate goal in the treatment of end-stage heart failure is the recovery of cardiac function following mechanical assistance of the left ventricle. The HVAD (TM) pump (HeartWare Inc.) left ventricular assist device (LVAD) can be explanted without resternotomy. This article illustrates that the usage of a custom-made mechanical plug (manufactured by INNOVO Solutions GmbH), which can be inserted into the LVAD's sewing ring, is feasible. This mechanical plug explicitly designed for device explantation is a viable alternative to the current standard of care. This article adopts a less invasive technique to explant the pump. The following case illustrates this technique.
CRIS-Team WoS Importer:2022-11-25

Reduced muscle strength in ether lipid-deficient mice is accompanied by altered development and function of the neuromuscular junction - Dorninger, Fabian; Herbst, Ruth; Kravic, Bojana; Camurdanoglu, Bahar Z.; Macinkovic, Igor; Zeitler, Gerhard; Forss-Petter, Sonja; Strack, Siegfried; Khan, Muzamil Majid; Waterham, Hans R.; Rudolf, Ruediger; Hashemolhosseini, Said; et al. (Journal of Neurochemistry, 2017)
Inherited deficiency in ether lipids, a subgroup of phospholipids whose biosynthesis needs peroxisomes, causes the fatal human disorder rhizomelic chondrodysplasia punctata. The exact roles of ether lipids in the mammalian organism and, therefore, the molecular mechanisms underlying the disease are still largely enigmatic. Here, we used glyceronephosphate O-acyltransferase knockout (Gnpat KO) mice to study the consequences of complete inactivation of ether lipid biosynthesis and documented substantial deficits in motor performance and muscle strength of these mice. We hypothesized that, probably in addition to previously described cerebellar abnormalities and myelination defects in the peripheral nervous system, an impairment of neuromuscular transmission contributes to the compromised motor abilities. Structurally, a morphologic examination of the neuromuscular junction (NMJ) in diaphragm muscle at different developmental stages revealed aberrant axonal branching and a strongly increased area of nerve innervation in Gnpat KO mice. Post-synaptically, acetylcholine receptor (AChR) clusters colocalized with nerve terminals within a widened endplate zone. In addition, we detected atypical AChR clustering, as indicated by decreased size and number of clusters following stimulation with agrin, in vitro. The turnover of AChRs was unaffected in ether lipid-deficient mice. Electrophysiological evaluation of the adult diaphragm indicated that although evoked potentials were unaltered in Gnpat KO mice, ether lipid deficiency leads to fewer spontaneous synaptic vesicle fusion events but, conversely, an increased post-synaptic response to spontaneous vesicle exocytosis. We conclude from our findings that ether lipids are essential for proper development and function of the NMJ and may, therefore, contribute to motor performance. Read the Editorial Highlight for this article on page 463.
EVALuna2:33477

Re-evaluation of neuronal P2X7 expression using novel mouse models and a P2X7-specific nanobody - Kaczmarek-Hajek, Karina; Zhang, Jiong; Kopp, Robin; Grosche, Antje; Rissiek, Bjoern; Saul, Anika; Bruzzone, Santina; Engel, Tobias; Jooss, Tina; Krautloher, Anna; Schuster, Stefanie; Magnus, Tim; et al. (eLife, 2018)
The P2X7 channel is involved in the pathogenesis of various CNS diseases. An increasing number of studies suggest its presence in neurons where its putative functions remain controversial for more than a decade. To resolve this issue and to provide a model for analysis of P2X7 functions, we generated P2X7 BAC transgenic mice that allow visualization of functional EGFP-tagged P2X7 receptors in vivo. Extensive characterization of these mice revealed dominant P2X7-EGFP protein expression in microglia, Bergmann glia, and oligodendrocytes, but not in neurons. These findings were further validated by microglia- and oligodendrocyte-specific P2X7 deletion and a novel P2X7-specific nanobody. In addition to the first quantitative analysis of P2X7 protein expression in the CNS, we show potential consequences of its overexpression in ischemic retina and post-traumatic cerebral cortex grey matter. This novel mouse model overcomes previous limitations in P2X7 research and will help to determine its physiological roles and contribution to diseases.
EVALuna2:35806

Regulation of Boundary Cap Neural Crest Stem Cell Differentiation after Transplantation. - Wegner, Michael; et al. (Stem cells, 2009)
Success of cell replacement therapies for neurological disorders will depend largely on the optimization of strategies to enhance viability and control the developmental fate of stem cells after transplantation. Once transplanted, stem/progenitor cells display a tendency to maintain an undifferentiated phenotype or differentiate into inappropriate cell types. Gain and loss of function experiments have revealed key transcription factors which drive differentiation of immature stem/progenitor cells toward more mature stages and eventually to full differentiation. An attractive course of action to promote survival and direct the differentiation of transplanted stem cells to a specific cell type would therefore be to force expression of regulatory differentiation molecules in already transplanted stem cells, using inducible gene expression systems which can be controlled from the outside. Here, we explore this hypothesis by employing a tetracycline gene regulating system (Tet-On) to drive the differentiation of boundary cap neural crest stem cells (bNCSCs) toward a sensory neuron fate after transplantation. We induced the expression of the key transcription factor Runx1 in Sox10-expressing bNCSCs. Forced expression of Runx1 strongly increased transplant survival in the enriched neurotrophic environment of the dorsal root ganglion cavity, and was sufficient to guide differentiation of bNCSCs toward a nonpeptidergic nociceptive sensory neuron phenotype both in vitro and in vivo after transplantation. These findings suggest that exogenous activation of transcription factors expression after transplantation in stem/progenitor cell grafts can be a constructive approach to control their survival as well as their differentiation to the desired type of cell and that the Tet-system is a useful tool to achieve this. © AlphaMed Press.
UnivIS-Import:2015-03-09:Pub.2009.med.IB.LPCIPDBI.regula
Keywords: In vitro; Mouse; Sensory neuron; Tet-system; Transcription factor; Transgene

Regulation of murine placentogenesis by the retroviral genes Syncytin-A, Syncytin-B and Peg10 - Henke, Christine; Ruebner, Matthias; Faschingbauer, Florian; Stolt, Claus; Schäfer, Natascha; Lang, Nadine; Beckmann, Matthias; Strissel, Pamela; Strick, Reiner (Differentiation, 2013)
The murine placenta has a trichorial structure with two multinucleated syncytiotrophoblast (SCT) layers representing a barrier between the maternal and fetal blood system. Genes of endogenous retroviruses and retrotransposon-derived paternally expressed genes (Peg), remnants of past infections and integrations in the genome, have essential functions in placentogenesis. Previous studies showed that the envelope genes Syncytin-A and Syncytin-B were essential for cell-cell fusion of the SCT. The goal of this study was to analyze the temporal localization and expression of nine genes throughout placental development from embryonic day (E)8.5 to E18.5 using in situ-hybridization and absolute RNA-quantification. These included a comparison of previously characterized genes from the labyrinth Syncytin-A, Syncytin-B, Gcm1, the junctional zone PL-1, PL-2, Plf, Tpbpa with two further characterized genes Peg10 and Tpbpb. Syncytin-A and Syncytin-B RNA localized to SCT-I and SCT-II, respectively. Peg10 RNA localized to all extraembryonic tissues, specifically to the parietal and sinusoidal TGC of the labyrinth layer, which is in contact with SCT-I and the maternal blood. All three retroviral/retrotransposon-derived genes showed the highest expression at E16.5, but Peg10 with 188,917.1 molecules/ng cDNA was 208-fold and 106.8-fold higher expressed than Syncytin-A and Syncytin-B, respectively. Tpbpb localized to the junctional zone and showed the highest expression at E16.5 along with PL-2, Plf, Tpbpa, but not PL-1, which decreased in expression at E10.5. To investigate a role of Syncytin-A, Syncytin-B and Peg10 in cell-cell fusion, we established a cell culture system with fractionated primary trophoblasts from murine placentae. Culturing trophoblasts for up to 72h partly resembled trophoblast development in vivo according to the nine marker genes. Knockdown of Syncytin-A demonstrated a functional regulation of cell-cell fusion, where knockdown of Peg10 showed no involvement in cell fusion. Due to the expression of Peg10 in TGCs, we propose an essential functional role in the fetal-maternal blood system.
EVALuna2:4934

Regulation of Sox9 by Sonic Hedgehog (Shh) is essential for patterning and formation of tracheal cartilage. - Wegner, Michael; et al. (Developmental Dynamics, 2010)
We report that Sonic Hedgehog (Shh) regulates both formation and patterning of tracheal cartilage by controlling the expression pattern and level of the chondrogenic gene, Sox9. In Shh-/- tracheo-esophageal tubes, Sox9 expression is transient and not restricted ventrally to the site of chondrogenesis, and is absent at the time of chondrogenesis, resulting in the failure of tracheal cartilage formation. Inhibition of Hedgehog signalling with cyclopamine in tracheal cultures prevents tracheal cartilage formation, while treatment of Shh-/- tracheal explant with exogenous Shh peptide rescues cartilage formation. Both exogenous Bmp4 and Noggin rescue cartilage phenotype in Shh-/- tracheal culture, while promoting excessive cartilage development in wild-type trachea through induction of Sox9 expression. The ventral and segmented expression of Sox9 in tracheal primordia under Shh modulated by Bmp4 and Noggin thus determine where and when tracheal cartilage develops. These results indicate that Shh signalling is a critical determinant in tracheal cartilage development. © 2009 Wiley-Liss, Inc.
UnivIS-Import:2015-03-09:Pub.2010.med.IB.LPCIPDBI.regula
Keywords: Mouse; Shh; Sox9; Tracheal cartilage

Reinhard Pharmazeutische Biologie 1, Grundlagen für Studium und Praxis - Dingermann, Theodor; Kreis, Wolfgang; Rimpler, Horst; Zündorf, Ilse (Wissenschaftliche Verlagsgesellschaft mbH, 2009)

Reinhard Pharmazeutische Biologie, Grundlagen und Humanbiologie - Dingermann, Theodor; Kreis, Wolfgang; Nieber, Karen; Rimpler, Horst; Zündorf, Ilse (Wissenschaftliche Verlagsgesellschaft, 2016)

Relative Quantification of N-(Carboxymethyl)lysine, Imidazolone A, and the Amadori Product in Glycated Lysozyme be MALDI-TOF Mass Spectrometry - Kislinger, Thomas; Humeny, Andreas; Peich, Carlo; Zhang, Xiaohong; Niwa, Toshimitsu; Pischetsrieder, Monika; Becker, Cord-Michael (Journal of Agricultural and Food Chemistry, 2003)
The nonenzymatic glycation of proteins by reducing sugars, also known as the Maillard reaction, has received increasing recognition from nutritional science and medical research. In this study, we applied matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) to perform relative and simultaneous quantification of the Amadori product, which is an early glycation product, and of Nε-(carboxymethyl)lysine and imidazolone A, two important advanced glycation end products. Therefore, native lysozyme was incubated with D-glucose for increasing periods of time (1, 4, 8, and 16 weeks) in phosphate-buffered saline pH 7.8 at 50 °C. After enzymatic digestion with endoproteinase Glu-C, the N-terminal peptide fragment (m/z 838; amino acid sequence KVFGRCE) and the C-terminal peptide fragment (m/z 1202; amino acid sequence VQAWIRGCRL) were used for relative quantification of the three Maillard products. Amadori product, Nε-(carboxymethyl)lysine, and imidazolone A were the main glycation products formed under these conditions. Their formation was dependent on glucose concentration and reaction time. The kinetics were similar to those obtained by competitive ELISA, an established method for quantification of Nε-(carboxymethyl)lysine and imidazolone A. Inhibition experiments showed that coincubation with Nα-acetylargine suppressed formation of imidazolone A but not of the Amadori product or Nε-(carboxymethyl)lysine. The presence of Nα-acetyllysine resulted in the inhibition of lysine modifications but in higher concentrations of imidazolone A. o-Phenylenediamine decreased the yield of the Amadori product and completely inhibited the formation of Nε-(carboxymethyl)lysine and imidazolone A. MALDI-TOF-MS proved to be a new analytical tool for the simultaneous, relative quantification of specific products of the Maillard reaction. For the first time, kinetic data of defined products on specific sites of glycated protein could be measured. This characterizes MALDI-TOF-MS as a valuable method for monitoring the Maillard reaction in the course of food processing.
UnivIS-Import:2015-03-09:Pub.2003.nat.dchph.llmch.relati
Keywords: Amadori product; Imidazolone A; Maillard reaction; MALDI-TOF-MS; N; Protein glycation

Renal tubular secretion of pramipexole - Knop, Jana; Hoier, Eva; Ebner, Thomas; Fromm, Martin; Müller, Fabian (European Journal of Pharmaceutical Sciences, 2015)
The dopamine agonist pramipexole is cleared predominantly by the kidney with a major contribution of active renal secretion. Previously the organic cation transporter 2 (OCT2) was shown to be involved in the uptake of pramipexole by renal tubular cells, while the mechanism underlying efflux into tubular lumen remains unclear. Cimetidine, a potent inhibitor of multidrug and toxin extrusion proteins 1 (MATE1) and 2-K (MATE2-K), decreases renal pramipexole clearance in humans. We hypothesized that, in addition to OCT2, pramipexole may be a substrate of MATE-mediated transport. Pramipexole uptake was investigated using MDCK or HEK cells overexpressing OCT2, MATE1 or MATE2-K and the respective vector controls (Co). Transcellular pramipexole transport was investigated in MDCK cells single- or double-transfected with OCT2 and/or MATE1 and in Co cells, separating a basal from an apical compartment in a model for renal tubular secretion. Pramipexole uptake was 1.6-, 1.1-, or 1.6-folds in cells overexpressing OCT2, MATE1 or MATE2-K, respectively as compared to Co cells (p<0.05). In transcellular transport experiments, intracellular pramipexole accumulation was 1.7-folds in MDCK-OCT2 (p<0.001), and transcellular pramipexole transport was 2.2- and 4.0-folds in MDCK-MATE1 and MDCK-OCT2-MATE1 cells as compared to Co cells (p<0.001). Transcellular pramipexole transport was pH dependent and inhibited by cimetidine with IC50 values of 12?M and 5.5?M in MATE1 and OCT2-MATE1 cells, respectively. Taken together, coordinate activity of OCT2-mediated uptake and MATE-mediated efflux determines pramipexole renal secretion. Reduced OCT2 or MATE transport activity due to genetic variation or drug-drug interactions may affect pramipexole renal secretion.
EVALuna2:8692

Repetitive injury and absence of monocytes promote astrocyte self-renewal and neurological recovery - Lange Canhos, Luisa; Chen, Muxin; Falk, Sven; Popper, Bastian; Straub, Tobias; Götz, Magdalena; Sirko, Swetlana (Glia, 2020)
Unlike microglia and NG2 glia, astrocytes are incapable of migrating to sites of injury in the posttraumatic cerebral cortex, instead relying on proliferation to replenish their numbers and distribution in the affected region. However, neither the spectrum of their proliferative repertoire nor their postinjury distribution has been examined in vivo. Using a combination of different thymidine analogs and clonal analysis in a model of repetitive traumatic brain injury, we show for the first time that astrocytes that are quiescent following an initial injury can be coerced to proliferate after a repeated insult in the cerebral cortex grey matter. Interestingly, this process is promoted by invasion of monocytes to the injury site, as their genetic ablation (using CCR2−/− mice) increased the number of repetitively dividing astrocytes at the expense of newly proliferating astrocytes in repeatedly injured parenchyma. These differences profoundly affected both the distribution of astrocytes and recovery period for posttraumatic behavior deficits suggesting key roles of astrocyte self-renewal in brain repair after injury.
CRIS-Team Scopus Importer:2020-08-07
Keywords: astrocyte topology; cognitive disfunction; inflammation; reactive gliosis; self-renew; TBI

Replacement of mouse Sox10 by the Drosophila ortholog Sox100B provides evidence for co-option of SoxE proteins into vertebrate-specific gene-regulatory networks through altered expression. - Sock, Elisabeth; Wegner, Michael; et al. (Developmental Biology, 2010)
Neural crest cells and oligodendrocytes as the myelinating glia of the central nervous system exist only in vertebrates. Their development is regulated by complex regulatory networks, of which the SoxE-type high-mobility-group domain transcription factors Sox8, Sox9 and Sox10 are essential components. Here we analyzed by in ovo electroporation in chicken and by gene replacement in the mouse whether the Drosophila ortholog Sox100B can functionally substitute for vertebrate SoxE proteins. Sox100B overexpression in the chicken neural tube led to the induction of neural crest cells as previously observed for vertebrate SoxE proteins. Furthermore, many aspects of neural crest and oligodendrocyte development were surprisingly normal in mice in which the Sox10 coding information was replaced by Sox100B arguing that Sox100B integrates well into the gene-regulatory networks that drive these processes. Our results therefore provide strong evidence for a model in which SoxE proteins were co-opted to these gene-regulatory networks mainly through the acquisition of novel expression patterns. However, later developmental defects in several neural crest derived lineages in mice homozygous for the Sox100B replacement allele indicate that some degree of functional specialization and adaptation of SoxE protein properties have taken place in addition to the co-option event. © 2010 Elsevier Inc.
UnivIS-Import:2015-03-09:Pub.2010.med.IB.LPCIPDBI.replac
Keywords: Glia; High-mobility-group; Neural crest; Oligodendrocyte; Satellite glia; Schwann cell; Sry

Replacement of related POU transcription factors leads to severe defects in mouse forebrain development. - Sock, Elisabeth; Reiprich, Simone; Müller, Jana; Stolt, Claus; Wegner, Michael; et al. (Developmental Biology, 2009)
Related transcription factors of the POU protein family show extensive overlap of expression in vivo and exhibit very similar biochemical properties in vitro. To study functional equivalence of class III POU proteins in vivo, we exchanged the Oct-6 gene by Brn-1 in the mouse. Brn-1 can fully replace Oct-6 in Schwann cells and rescue peripheral nervous system development in these mice. The same mice, however, exhibit severe defects in forebrain development arguing that Oct-6 and Brn-1 are not functionally equivalent in the central nervous system. The cause of the observed forebrain phenotype is complex, but anteriorly expanded Wnt1 expression contributes. Oct-6 normally represses Wnt1 expression in the early diencephalon and replacement by Brn-1 as a weaker inhibitor is no longer sufficient to maintain the necessary level of repression in the mouse mutant. The extent of functional equivalence between related transcription factors is thus strongly dependent on the analyzed tissue. © 2009 Elsevier Inc. All rights reserved.
UnivIS-Import:2015-03-09:Pub.2009.med.IB.LPCIPDBI.replac
Keywords: Brain malformation; Brn-1; Functional equivalence; Homeodomain; Oct-6; Redundancy; Transcription factor; Wnt signalling

Replacement of the Sox10 transcription factor by Sox8 reveals incomplete functional equivalence. - Wegner, Michael; Stolt, Claus; et al. (Development, 2006)
Sox8 and Sox10 are two closely related transcription factors of the Sox protein family with overlapping expression patterns during development. They are believed to perform very similar functions because several developmental processes, including enteric nervous system development and oligodendrocyte differentiation, are regulated by both Sox proteins. To analyze the extent of functional equivalence between the two Sox proteins, we employed targeted mutagenesis to replace Sox10 with Sox8 in the mouse. In mice that expressed Sox8 instead of Sox10, Sox10 deficiency was phenotypically rescued to different extents in affected tissues. Whereas development of glial cells and neurons in the sensory and sympathetic parts of the peripheral nervous system was almost normal when Sox10 was replaced by Sox8, melanocyte development was as defective as in Sox10-deficient mice. The ability of Sox8 to rescue the defects in enteric nervous system development and oligodendrocyte differentiation of Sox10-deficient mice was limited. We conclude that the extent of functional equivalence depends on the tissue and that, despite their relatedness, Sox8 and Sox10 have more unique functions than previously appreciated.
UnivIS-Import:2015-03-09:Pub.2006.med.IB.LPCIPDBI.replac
Keywords: Glia; High-mobility-group; Neural crest; Oligodendrocyte; Redundancy; Sry

Reprogramming a maize plant: transcriptional and metabolic changes induced by the fungal biotroph Ustilago maydis - Doehlemann, Gunther; Wahl, Ramon; Horst, Robin J.; Voll, Lars M.; Usadel, Bjoern; Poree, Fabien; Stitt, Mark; Pons-Kuehnemann, Joern; Sonnewald, Uwe; Kahmann, Regine; Kaemper, Joerg (Plant Journal, 2008)
The fungal pathogen Ustilago maydis establishes a biotrophic relationship with its host plant maize (Zea mays). Hallmarks of the disease are large plant tumours in which fungal proliferation occurs. Previous studies suggested that classical defence pathways are not activated. Confocal microscopy, global expression profiling and metabolic profiling now shows that U. maydis is recognized early and triggers defence responses. Many of these early response genes are downregulated at later time points, whereas several genes associated with suppression of cell death are induced. The interplay between fungus and host involves changes in hormone signalling, induction of antioxidant and secondary metabolism, as well as the prevention of source leaf establishment. Our data provide novel insights into the complexity of a biotrophic interaction.
Keywords: microarray; biotrophy; Zea mays; Ustilago maydis; metabolite profiling; defence signalling

Reprogramming of pericyte-derived cells of the adult human brain into induced neuronal cells - Karow, Marisa; Sanchez, Rodrigo; Schichor, Christian; Masserdotti, Giacomo; Ortega, Felipe; Heinrich, Christophe; Gascon, Sergio; Khan, Muhammad A.; Lie, Dieter Chichung; Dellavalle, Arianna; Cossu, Giulio; Goldbrunner, Roland; et al. (Cell Stem Cell, 2012)
Reprogramming of somatic cells into neurons provides a new approach toward cell-based therapy of neurodegenerative diseases. A major challenge for the translation of neuronal reprogramming into therapy is whether the adult human brain contains cell populations amenable to direct somatic cell conversion. Here we show that cells from the adult human cerebral cortex expressing pericyte hallmarks can be reprogrammed into neuronal cells by retrovirus-mediated coexpression of the transcription factors Sox2 and Mash1. These induced neuronal cells acquire the ability of repetitive action potential firing and serve as synaptic targets for other neurons, indicating their capability of integrating into neural networks. Genetic fate-mapping in mice expressing an inducible Cre recombinase under the tissue-nonspecific alkaline phosphatase promoter corroborated the pericytic origin of the reprogrammed cells. Our results raise the possibility of functional conversion of endogenous cells in the adult human brain to induced neuronal fates.
EVALuna2:26316

Responsiveness of B cells is regulated by the hinge region of IgD - Uebelhart, Rudolf; Hug, Eva; Bach, Martina P.; Wossning, Thomas; Duehren-Von Minden, Marcus; Horn, Anselm; Tsiantoulas, Dimitrios; Kometani, Kohei; Kurosaki, Tomohiro; Binder, Christoph J.; Sticht, Heinrich; Nitschke, Lars; et al. (Nature Immunology, 2015)
Mature B cells express immunoglobulin M (IgM)- and IgD-isotype B cell antigen receptors, but the importance of IgD for B cell function has been unclear. By using a cellular in vitro system and corresponding mouse models, we found that antigens with low valence activated IgM receptors but failed to trigger IgD signaling, whereas polyvalent antigens activated both receptor types. Investigations of the molecular mechanism showed that deletion of the IgD-specific hinge region rendered IgD responsive to monovalent antigen, whereas transferring the hinge to IgM resulted in responsiveness only to polyvalent antigen. Our data suggest that the increased IgD/IgM ratio on conventional B-2 cells is important for preferential immune responses to antigens in immune complexes, and that the increased IgM expression on B-1 cells is essential for B-1 cell homeostasis and function.
EVALuna2:26294

Restricted expression of mGCMa in kidney ind thymus - Hashemolhosseini, Said; Hadjihannas, Michel; Haase, Christian; Amann, Kerstin Ute; Wegner, Michael (Mechanisms of Development, 2002)
UnivIS-Import:2015-04-14:Pub.2002.forsch.sonder.sfb423.restri

Restricted expression of mouse GCMa/Gcm1 in kidney and thymus - Hashemolhosseini, Said; Stolt, Claus; Wegner, Michael; et al. (Mechanisms of Development, 2002)
Mouse Glial Cells Missing a (mGCMa) belongs to a small family of transcription factors named after the prototypical GCM from Drosophila. mGCMa was expected to regulate gliogenesis, but instead found to be primarily expressed during development in trophoblasts of chorion and labyrinth. Its deletion causes abnormal placental labyrinth formation and results in embryonic lethality. Here we identify kidney and thymus as sites of mGCMa expression. In thymus, mGCMa is restricted to few small clusters of cells, in kidney to the S3 segment of proximal tubules. mGCMa expression is primarily postnatal, arguing for a role in organ function rather than organ development. © 2002 Elsevier Science Ireland Ltd. All rights reserved.
UnivIS-Import:2015-04-14:Pub.2002.med.IB.LPCIPDBI.restri
Keywords: GCM; Kidney; Thymus; Proximal tubule; S3 segment

RKIP regulates differentiation-related features in melanocytic cells - Penas, Cristina; Apraiz, Aintzane; Muñoa, Iraia; Arroyo-Berdugo, Yoana; Rasero, Javier; Ezkurra, Pilar A.; Velasco, Veronica; Subiran, Nerea; Boßerhoff, Anja Katrin; Alonso, Santos; Asumendi, Aintzane; Boyano, Maria D. (Cancers, 2020)
Raf Kinase Inhibitor Protein (RKIP) has been extensively reported as an inhibitor of key signaling pathways involved in the aggressive tumor phenotype and shows decreased expression in several types of cancers. However, little is known about RKIP in melanoma or regarding its function in normal cells. We examined the role of RKIP in both primary melanocytes and malignant melanoma cells and evaluated its diagnostic and prognostic value. IHC analysis revealed a significantly higher expression of RKIP in nevi compared with early-stage (stage I–II, AJCC 8th) melanoma biopsies. Proliferation, wound healing, and collagen-coated transwell assays uncovered the implication of RKIP on the motility but not on the proliferative capacity of melanoma cells as RKIP protein levels were inversely correlated with the migration capacity of both primary and metastatic melanoma cells but did not alter other parameters. As shown by RNA sequencing, endogenous RKIP knockdown in primary melanocytes triggered the deregulation of cellular differentiation-related processes, including genes (i.e., ZEB1, THY-1) closely related to the EMT. Interestingly, NANOG was identified as a putative transcriptional regulator of many of the deregulated genes, and RKIP was able to decrease the activation of the NANOG promoter. As a whole, our data support the utility of RKIP as a diagnostic marker for early-stage melanomas. In addition, these findings indicate its participation in the maintenance of a differentiated state of melanocytic cells by modulating genes intimately linked to the cellular motility and explain the progressive decrease of RKIP often described in tumors.
CRIS-Team Scopus Importer:2020-06-16
Keywords: Biomarker; Cell motility; Differentiation; Melanocytes; Melanoma; RKIP; Transcriptome analysis

RNA interference machinery-mediated gene regulation in mouse adult neural stem cells - Cernilogar, Filippo M.; Di Giaimo, Rossella; Rehfeld, Frederick; Cappello, Silvia; Lie, Dieter Chichung (BMC Neuroscience, 2015)
Neurogenesis in the brain of adult mammals occurs throughout life in two locations: the subventricular zone of the lateral ventricle and the subgranular zone of the dentate gyrus in the hippocampus. RNA interference mechanisms have emerged as critical regulators of neuronal differentiation. However, to date, little is known about its function in adult neurogenesis.Here we show that the RNA interference machinery regulates Doublecortin levels and is associated with chromatin in differentiating adult neural progenitors. Deletion of Dicer causes abnormal higher levels of Doublecortin. The microRNA pathway plays an important role in Doublecortin regulation. In particular miRNA-128 overexpression can reduce Doublecortin levels in differentiating adult neural progenitors.We conclude that the RNA interference components play an important role, even through chromatin association, in regulating neuron-specific gene expression programs.
EVALuna2:26327

RNA-seq analysis identifies different transcriptomic types and developmental trajectories of primary melanomas - Kunz, Manfred; Loeffler-Wirth, Henry; Dannemann, Michael; Willscher, Edith; Doose, Gero; Kelso, Janet; Kottek, Tina; Nickel, Birgit; Hopp, Lydia; Landsberg, Jenny; Hoffmann, Steve; Tueting, Thomas; et al. (Oncogene, 2018)
Recent studies revealed trajectories of mutational events in early melanomagenesis, but the accompanying changes in gene expression are far less understood. Therefore, we performed a comprehensive RNA-seq analysis of laser-microdissected melanocytic nevi (n = 23) and primary melanoma samples (n = 57) and characterized the molecular mechanisms of early melanoma development. Using self-organizing maps, unsupervised clustering, and analysis of pseudotime (PT) dynamics to identify evolutionary trajectories, we describe here two transcriptomic types of melanocytic nevi (N1 and N2) and primary melanomas (M1 and M2). N1/M1 lesions are characterized by pigmentation-type and MITF gene signatures, and a high prevalence of NRAS mutations in M1 melanomas. N2/M2 lesions are characterized by inflammatory-type and AXL gene signatures with an equal distribution of wild-type and mutated BRAF and low prevalence of NRAS mutations in M2 melanomas. Interestingly, N1 nevi and M1 melanomas and N2 nevi and M2 melanomas, respectively, cluster together, but there is no clustering in a stage-dependent manner. Transcriptional signatures of M1 melanomas harbor signatures of BRAF/MEK inhibitor resistance and M2 melanomas harbor signatures of anti-PD-1 antibody treatment resistance. Pseudotime dynamics of nevus and melanoma samples are suggestive for a switch-like immune-escape mechanism in melanoma development with downregulation of immune genes paralleled by an increasing expression of a cell cycle signature in late-stage melanomas. Taken together, the transcriptome analysis identifies gene signatures and mechanisms underlying development of melanoma in early and late stages with relevance for diagnostics and therapy.
EVALuna2:196749

Robo3A and Robo3B expression is regulated via alternative promoters and mRNA stability - Ruedel, Anke; Schott, Mandy; Schubert, Thomas; Boßerhoff, Anja Katrin (Cancer Cell International, 2016)
Background: The transmembrane receptor family Roundabout (Robo) was described to have an essential role in the developing nervous system. Recent studies demonstrated that Robo3 shows an altered expression in rheumatoid arthritis as well as in melanoma. Context and purpose of the study: Until today no detailed studies of the two Robo3 isoforms (Robo3A and Robo3B) and their roles in rheumatoid arthritis synovial fibroblasts, respectively malignant melanoma are available. To get a better understanding regarding the role of Robo3A and Robo3B in the molecular process of rheumatoid arthritis and melanoma the exact characterization of expression and regulation is object of this study. Results: mRNA and protein expression of the transcriptional variants were analyzed by quantitative RT-PCR respectively western blotting and revealed particularly enhanced expression of Robo3B in rheumatoid arthritis and melanoma. Promoter assays and inhibitor studies also disclosed that there is apparently a cell- and isoform-specific regulation of the Robo3 expression. Finally, dissimilar mRNA stabilities of Robo3A and Robo3B are identified as decisive posttranscriptional gene expression control. Conclusion: In summary, this study supported an isotype specific role of Robo3B in disease hinting to different functional roles of each isoform.
CRIS-Team Scopus Importer:2022-08-05
Keywords: Malignant melanoma; Repellent factor; Rheumatoid arthritis; Robo

Rod photoreceptor ribbon synapses in DBA/2J mice show progressive age-related structural changes. - Fuchs, Michaela; Scholz, Michael; Sendelbeck, Anna; Atorf, Jenny; Schlegel, Christine Julie; Enz, Ralf; Brandstätter, Johann Helmut (PLoS ONE, 2012)
The DBA/2J mouse is a commonly used animal model in glaucoma research. The eyes of DBA/2J mice show severe age-related changes that finally lead to the degeneration of retinal ganglion cells and the optic nerve. Recent electroretinogram studies identified functional deficits, which suggest that also photoreceptor cells are involved in the pathological processes occurring in the DBA/2J mouse retina. In a comparative study, we examined anatomical and molecular changes in the retinae of DBA/2J and C57BL/6 control mice with light and electron microscopy and with PCR analyses. In the retina of the DBA/2J mouse, we found a thinning of the outer plexiform layer, the first synaptic layer in the transfer of visual signals, and age-dependent and progressive degenerative structural changes at rod photoreceptor ribbon synapses. The structural ribbon changes represent a photoreceptor synaptic phenotype that has not yet been described in this animal model of secondary angle-closure glaucoma. Furthermore, genes of the classical complement cascade were upregulated in the photoreceptor cells of aging DBA/2J mice, suggesting a putative link between ribbon synapse degradation and the innate immune system. © 2012 Fuchs et al.
UnivIS-Import:2015-04-14:Pub.2012.med.IB.profes_1.rodpho

Role of Amino Acid Transporter SNAT1/SLC38A1 in Human Melanoma - Böhme-Schäfer, Ines; Lörentz, Sandra; Boßerhoff, Anja Katrin (Cancers, 2022)
The tumor metabolism is an important driver of cancer cell survival and growth, as rapidly dividing tumor cells exhibit a high demand for energetic sources and must adapt to microenviron-mental changes. Therefore, metabolic reprogramming of cancer cells and the associated deregulation of nutrient transporters are a hallmark of cancer cells. Amino acids are essential for cancer cells to synthesize the necessary amount of protein, DNA, and RNA. Although cancer cells can synthesize glutamine de novo, most cancer cells show an increased uptake of glutamine from the tumor microen-vironment. Especially SNAT1/SLC38A1, a member of the sodium neutral amino acid transporter (SNAT) family, plays an essential role during major net import of glutamine. In this study, we revealed a significant upregulation of SNAT1 expression in human melanoma tissue in comparison to healthy epidermis and an increased SNAT1 expression level in human melanoma cell lines when compared to normal human melanocytes (NHEMs). We demonstrated that functional inhibition of SNAT1 with α-(methylamino) isobutyric acid (MeAIB), as well as siRNA-mediated downregulation reduces cancer cell growth, cellular migration, invasion, and leads to induction of senescence in melanoma cells. Consequently, these results demonstrate that the amino acid transporter SNAT1 is essential for cancer growth, and indicates a potential target for cancer chemotherapy.
CRIS-Team Scopus Importer:2022-05-06
Keywords: amino acid transporter; melanoma; tumor metabolism

Role of astrocytes in the neurogenic niches - Schneider, Julia; Karpf, Julian; Beckervordersandforth, Ruth (Astrocytes, 2019)
In the mammalian brain, highly specialized astrocytes serve as neural stem cells (NSCs) that divide and give rise to new neurons, in a process called neurogenesis. During embryonic development NSCs generate almost all neurons of the brain. Soon after birth the neurogenic potential of NSCs is highly reduced, and neurogenesis occurs only in two specialized brain regions called the neurogenic niches. Niche cells are essential to stem cells as they provide structural and nutritional support, and control fundamental stem cell decisions. Astrocytes, major components of the adult neurogenic niches, are evolving as important regulators of neurogenesis, by controlling NSC proliferation, fate choice, and differentiation of the progeny. Therefore, astrocytes contribute to neurogenesis in two ways: As NSCs and as niche cells. This review highlights the role of astrocyte-like NSCs during development and adulthood, and summarizes how niche astrocytes control the process of adult neurogenesis.
CRIS-Team Scopus Importer:2019-07-30
Keywords: Adult neurogenesis; Astrocytes; Neural stem cell niche; Neural stem cells

Role of fibroblast growth factor signalling in hepatic fibrosis - Seitz, Tatjana; Hellerbrand, Claus (Liver International, 2021)
Fibrotic remodelling is a highly conserved protective response to tissue injury and it is essential for the maintenance of structural and functional tissue integrity. Also hepatic fibrosis can be considered as a wound-healing response to liver injury, reflecting a balance between liver repair and scar formation. In contrast, pathological fibrosis corresponds to impaired wound healing. Usually, the liver regenerates after acute injury. However, if the damaging mechanisms persist, the liver reacts with progressive and uncontrolled accumulation of extracellular matrix proteins. Eventually, excessive fibrosis can lead to cirrhosis and hepatic failure. Furthermore, cirrhosis is the major risk factor for the development of hepatocellular cancer (HCC). Therefore, hepatic fibrosis is the most critical pathological factor that determines the morbidity and mortality of patients with chronic liver disease. Still, no effective anti-fibrogenic therapies exist, despite the very high medical need. The regulation of fibroblast growth factor (FGF) signalling is a prerequisite for adequate wound healing, repair and homeostasis in various tissues and organs. The FGF family comprises 22 proteins that can be classified into paracrine, intracrine and endocrine factors. Most FGFs signal through transmembrane tyrosine kinase FGF receptors (FGFRs). Although FGFRs are promising targets for the treatment of HCC, the expression and function of FGFR-ligands in hepatic fibrosis is still poorly understood. This review summarizes the latest advances in our understanding of FGF signalling in hepatic fibrosis. Furthermore, the potential of FGFs as targets for the treatment of hepatic fibrosis and remaining challenges for the field are discussed.
CRIS-Team Scopus Importer:2021-04-02
Keywords: FGF; fibroblast growth factors; fibrosis; hepatic stellate cells; wound healing

Role of Fibroblast Growth Factors in the Crosstalk of Hepatic Stellate Cells and Uveal Melanoma Cells in the Liver Metastatic Niche - Seitz, Tatjana; John, Nora; Sommer, Judith; Dietrich, Peter; Thasler, Wolfgang E.; Hartmann, Arndt; Evert, Katja; Lang, Sven A.; Boßerhoff, Anja Katrin; Hellerbrand, Claus (International Journal of Molecular Sciences, 2022)
Hepatic metastasis is the critical factor determining tumor-associated mortality in different types of cancer. This is particularly true for uveal melanoma (UM), which almost exclusively metastasizes to the liver. Hepatic stellate cells (HSCs) are the precursors of tumor-associated fibroblasts and support the growth of metastases. However, the underlying mechanisms are widely unknown. Fibroblast growth factor (FGF) signaling is dysregulated in many types of cancer. The aim of this study was to analyze the pro-tumorigenic effects of HSCs on UM cells and the role of FGFs in this crosstalk. Conditioned medium (CM) from activated human HSCs significantly induced proliferation together with enhanced ERK and JNK activation in UM cells. An in silico database analysis revealed that there are almost no mutations of FGF receptors (FGFR) in UM. However, a high FGFR expression was found to be associated with poor survival for UM patients. In vitro, the pro-tumorigenic effects of HSC-CM on UM cells were abrogated by a pharmacological inhibitor (BGJ398) of FGFR1/2/3. The expression analysis revealed that the majority of paracrine FGFs are expressed by HSCs, but not by UM cells, including FGF9. Furthermore, the immunofluorescence analysis indicated HSCs as a cellular source of FGF9 in hepatic metastases of UM patients. Treatment with recombinant FGF9 significantly enhanced the proliferation of UM cells, and this effect was efficiently blocked by the FGFR1/2/3 inhibitor BGJ398. Our study indicates that FGF9 released by HSCs promotes the tumorigenicity of UM cells, and thus suggests FGF9 as a promising therapeutic target in hepatic metastasis.
CRIS-Team Scopus Importer:2022-10-28
Keywords: fibroblast growth factor 9; fibroblast growth factors; hepatic metastasis; hepatic stellate cells; uveal melanoma

Role of glial 14-3-3 gamma protein in autoimmune demyelination - Lee, De-Hyung; Steinacker, Petra; Seubert, Silvia; Turnescu-Uzat, Tanja; Melms, Arthur; Manzel, Arndt; Otto, Markus; Linker, Ralf (Journal of Neuroinflammation, 2015)
The family of 14-3-3 proteins plays an important role in the regulation of cell survival and death. Here, we investigate the role of the 14-3-3 gamma (14-3-3 ?) subunit for glial responses in autoimmune demyelination.Expression of 14-3-3 ? in glial cell culture was investigated by reverse transcription polymerase chain reaction (RT-PCR) and immunocytochemistry. 14-3-3 ? knockout mice were subjected to murine myelin oligodendrocyte-induced experimental autoimmune encephalomyelitis (MOG-EAE), an animal model mimicking inflammatory features and neurodegenerative aspects of multiple sclerosis (MS).Expression studies in cell culture confined expression of 14-3-3 ? to both, oligodendrocytes (OL) and astrocytes. RT-PCR analysis revealed an increased expression of 14-3-3 ? mRNA in the spinal cord during the late chronic phase of MOG-EAE. At that stage, EAE was more severe in 14-3-3 ? knockout mice as compared to age- and gender-matched controls. Histopathological analyses on day 56 post immunization (p.i.) revealed significantly enhanced myelin damage as well as OL injury and secondary, an increase in axonal injury and gliosis in 14-3-3 ? -/- mice. At the same time, deficiency in 14-3-3 ? protein did not influence the immune response. Further histological studies revealed an increased susceptibility towards apoptosis in 14-3-3 ?-deficient OL in the inflamed spinal cord.These data argue for a pivotal role of 14-3-3 ?-mediated signalling pathways for OL protection in neuroinflammation.
EVALuna2:22340

Role of mammalian target of rapamycin complex 2 in primary and secondary liver cancer - Joechle, Katharina; Cramer, Thorsten; Neumann, Ulf Peter; Lang, Sven Arke; Guenzle, Jessica; Hellerbrand, Claus; Strnad, Pavel (World Journal of Gastrointestinal Oncology, 2021)
The mammalian target of rapamycin (mTOR) acts in two structurally and functionally distinct protein complexes, mTOR complex 1 (mTORC1) and mTOR complex 2 (mTORC2). Upon deregulation, activated mTOR signaling is associated with multiple processes involved in tumor growth and metastasis. Compared with mTORC1, much less is known about mTORC2 in cancer, mainly because of the unavailability of a selective inhibitor. However, existing data suggest that mTORC2 with its two distinct subunits Rictor and mSin1 might play a more important role than assumed so far. It is one of the key effectors of the PI3K/AKT/mTOR pathway and stimulates cell growth, cell survival, metabolism, and cytoskeletal organization. It is not only implicated in tumor progression, metastasis, and the tumor microenvironment but also in resistance to therapy. Rictor, the central subunit of mTORC2, was found to be upregulated in different kinds of cancers and is associated with advanced tumor stages and a bad prognosis. Moreover, AKT, the main downstream regulator of mTORC2/Rictor, is one of the most highly activated proteins in cancer. Primary and secondary liver cancer are major problems for current cancer therapy due to the lack of specific medical treatment, emphasizing the need for further therapeutic options. This review, therefore, summarizes the role of mTORC2/Rictor in cancer, with special focus on primary liver cancer but also on liver metastases.
CRIS-Team Scopus Importer:2021-12-10
Keywords: Cholangiocellular carcinoma; Hepatocellular carcinoma; Liver cancer; Liver metastases; Mammalian target of rapamycin; Mammalian target of rapamycin complex 2; Rictor

Role of melanoma inhibitory activity in melanocyte senescence - Feuerer, Lena; Lamm, Susanne; Henz, Ingmar; Kappelmann-Fenzl, Melanie; Haferkamp, Sebastian; Meierjohann, Svenja; Hellerbrand, Claus; Kuphal, Silke; Boßerhoff, Anja Katrin (Pigment Cell & Melanoma Research, 2019)
The protein melanoma inhibitory activity (MIA) is known to be expressed in melanoma and to support melanoma progression. Interestingly, previous studies also observed the expression of MIA in nevi. Concentrating on these findings, we revealed that MIA expression is correlated with a senescent state in melanocytes. Induction of replicative or oncogene-induced senescence resulted in increased MIA expression in vitro. Notably, MIA knockdown in senescent melanocytes reduced the percentage of senescence-associated beta-Gal-positive cells and enhanced proliferation. Using the melanoma mouse model Tg(Grm1), MIA-deficient mice supported the impact of MIA on senescence by showing a significantly earlier tumor onset compared to controls. In melanocytes, MIA knockdown led to a downregulation of the cell cycle inhibitor p21 in vitro and in vivo. In contrast, after induction of hTERT in human melanoma cells, p21 regulation by MIA was lost. In summary, our data show for the first time that MIA is a regulator of cellular senescence in human and murine melanocytes.
CRIS-Team Scopus Importer:2019-07-02
Keywords: melanocyte; melanoma inhibitory activity; oncogene-induced senescence; p21; senescence; telomerase

Role of mitochondrial fusion dynamics in adult hippocampal NSC lineage progression - Wendler, S. M. V.; Wani, G.; Goebel, J.; Conzelmann, K-K.; Lie, Dieter Chichung; Bergami, M. (GLIA, 2019)
CRIS-Team WoS Importer:2020-01-10

Role of Mitochondrial Metabolism in the Control of Early Lineage Progression and Aging Phenotypes in Adult Hippocampal Neurogenesis - Beckervordersandforth, Ruth; Ebert, Birgit; Schäffner, Iris; Moss, Jonathan; Fiebig, Christian; Shin, Jaehoon; Moore, Darcie L.; Ghosh, Laboni; Trinchero, Mariela F.; Stockburger, Carola; Friedland, Kristina; Steib, Kathrin; et al. (Neuron, 2017)
EVALuna2:4763

Role of the N-terminus for the stability of an amyloid-β fibril with three-fold symmetry - Söldner, Christian; Sticht, Heinrich; Horn, Anselm (PLoS ONE, 2017)
A key player in Alzheimer's disease is the peptide amyloid-beta (Aβ), whose aggregation into small soluble oligomers, protofilaments, and fibrils finally leads to plaque deposits in human brains. The aggregation behavior of Aβ is strongly modulated by the nature and composition of the peptide's environment and by its primary sequence properties. The N-terminal residues of Aβ play an important role, because they are known to change the peptide's aggregation propensity. Since these residues are for the first time completely resolved at the molecular level in a three-fold symmetric fibril structure derived from a patient, we chose that system as template for a systematic investigation of the influence of the N-terminus upon structural stability. Using atomistic molecular dynamics simulations, we examined several fibrillar systems comprising three, six, twelve and an infinite number of layers, both with and without the first eight residues. First, we found that three layers are not sufficient to stabilize the respective Aβ topology. Second, we observed a clear stabilizing effect of the N-terminal residues upon the overall fibril fold: truncated Aβ systems were less stable than their full-length counterparts. The N-terminal residues Arg5, Asp7, and Ser8 were found to form important interfilament contacts stabilizing the overall fibril structure of three-fold symmetry. Finally, similar structural rearrangements of the truncated Aβ species in different simulations prompted us to suggest a potential mechanism involved in the formation of amyloid fibrils with three-fold symmetry.
EVALuna2:33720

Role of the Pbrm1 subunit and the PBAF complex in Schwann cell development - Polanetzki, Vanessa; Fröb, Franziska; Baroti, Tina; Schimmel, Margit; Tamm, Ernst R.; Wegner, Michael (Scientific Reports, 2022)
Myelin sheath formation in the peripheral nervous system and the ensuing saltatory conduction rely on differentiated Schwann cells. We have previously shown that transition of Schwann cells from an immature into a differentiated state requires Brg1 that serves as the central energy generating subunit in two related SWI/SNF-type chromatin remodelers, the BAF and the PBAF complex. Here we used conditional deletion of Pbrm1 to selectively interfere with the PBAF complex in Schwann cells. Despite efficient loss of Pbrm1 early during lineage progression, we failed to detect any substantial alterations in the number, proliferation or survival of immature Schwann cells as well as in their rate and timing of terminal differentiation. As a consequence, postnatal myelin formation in peripheral nerves appeared normal. There were no inflammatory alterations in the nerve or other signs of a peripheral neuropathy. We conclude from our study that Pbrm1 and very likely the PBAF complex are dispensable for proper Schwann cell development and that Schwann cell defects previously observed upon Brg1 deletion are mostly attributable to altered or absent function of the BAF complex.
CRIS-Team Scopus Importer:2022-02-25

Role of two single nucleotide polymorphisms in secreted frizzled related protein 1 and bladder cancer risk - Rogler, Anja; Hoja, Sabine; Socher, Eileen; Nolte, Elke; Wach, Sven; Wieland, Wolf; Hofstädter, Ferdinand; Goebell, Peter; Wullich, Bernd; Hartmann, Arndt; Stoehr, Robert (International Journal of Clinical and Experimental Pathology, 2013)
In this study, we determined the genotype distribution of two single nucleotide polymorphisms (SNPs) in secreted frizzled related protein 1 (SFRP1), rs3242 and rs921142, in a Caucasian bladder cancer case-control study. Allelic variants of the SNPs were determined using restriction fragment length polymorphism (RFLP) analysis and partly verified by sequencing analysis. Overall, DNA from 188 consecutive and 215 early-onset bladder cancer patients (≤45 years) as well as from 332 controls was investigated. Potential microRNA binding sites were determined for rs3242, and microRNA expression was analysed in cell lines and tumour specimens. We observed a remarkable distribution difference in rs3242 between bladder cancer patients and healthy controls (p=0.05). Additionally, we found a significant difference in genotype distribution (p=0.032), resulting from the difference of early-onset patients and the control group (p=0.007). The risk allele T showed increased frequency in the early-onset patient group (p=0.002). Genotype-dependent differences of microRNA binding capacity were predicted in SFRP1 mRNA for two microRNAs. Hsa-miR-3646 showed strong expression in cell lines and tumour tissue, whereas hsa-miR-603 exhibited weak expression. The rs921142 SNP showed no significant association with bladder cancer risk. This is the first study to describe an association of the SFRP1 SNP rs3242 and bladder cancer risk as well as the influence of rs3242 on genotype-dependent microRNA capacity on SFRP1 mRNA. The onset of bladder seems to be associated with the increased occurrence of the T-allele in rs3242.
Keywords: Bladder cancer; Microrna; Sfrp1; Snp; Wnt signalling pathway

ROS is the boss - Hahn, Jonas; Kienhofer, Deborah; Stoof, Julia; Csepregi, Janka Zsofia; Reinwald, Christiane; Maueröder, Christian; Urbonaviciute, Vilma; Munoz, Luis Enrique; Hultqvist, Malin; Podolska, Malgorzata; Biermann, Mona; Leppkes, Moritz; et al. (2017)
EVALuna2:13467

SARS-CoV-2-seronegative subjects target CTL epitopes in the SARS-CoV-2 nucleoprotein cross-reactive to common cold coronaviruses - Schmidt, Kristin; Nganou-Makamdop, K.; Tenbusch, Matthias; El Kenz, B.; Maier, Clara; Lapuente, Dennis; Überla, Klaus; Spriewald, Bernd; Bergmann, Sabrina; Harrer, Ellen; Harrer, Thomas (JOURNAL OF THE INTERNATIONAL AIDS SOCIETY, 2021)
CRIS-Team WoS Importer:2021-11-26

Schwann cells and their transcriptional network: Evolution of key regulators of peripheral myelination - Stolt, Claus; Wegner, Michael (Brain Research, 2016)
As derivatives of the neural crest, Schwann cells represent a vertebrate invention. Their development and differentiation is under control of a newly constructed, vertebrate-specific regulatory network that contains Sox10, Oct6 and Krox20 as cornerstones and central regulators of peripheral myelination. In this review, we discuss the function and relationship of these transcription factors among each other and in the context of their regulatory network, and present ideas of how neofunctionalization may have helped to recruit them to their novel task in Schwann cells. This article is part of a Special Issue entitled SI: Myelin Evolution.
EVALuna2:4985

scRNA sequencing uncovers a TCF4-dependent transcription factor network regulating commissure development in mouse - Wittmann, Marie-Theres; Katada, Sayako; Sock, Elisabeth; Kirchner, Philipp; Ekici, Arif Bülent; Wegner, Michael; Nakashima, Kinichi; Lie, Dieter Chichung; Reis, André (Development, 2021)
Transcription factor 4 (TCF4) is a crucial regulator of neurodevelopment and has been linked to the pathogenesis of autism, intellectual disability and schizophrenia. As a class I bHLH transcription factor (TF), it is assumed that TCF4 exerts its neurodevelopmental functions through dimerization with proneural class II bHLH TFs. Here, we aim to identify TF partners of TCF4 in the control of interhemispheric connectivity formation. Using a new bioinformatic strategy integrating TF expression levels and regulon activities from single cell RNA-sequencing data, we find evidence that TCF4 interacts with non-bHLH TFs and modulates their transcriptional activity in Satb2+ intercortical projection neurons. Notably, this network comprises regulators linked to the pathogenesis of neurodevelopmental disorders, e.g. FOXG1, SOX11 and BRG1. In support of the functional interaction of TCF4 with non-bHLH TFs, we find that TCF4 and SOX11 biochemically interact and cooperatively control commissure formation in vivo, and regulate the transcription of genes implicated in this process. In addition to identifying new candidate interactors of TCF4 in neurodevelopment, this study illustrates how scRNA-Seq data can be leveraged to predict TF networks in neurodevelopmental processes.
CRIS-Team Scopus Importer:2021-08-13
Keywords: Commissure development; Gene regulatory networks; Mouse; Protein-protein interaction; Single-cell RNA sequencing; SOX11; TCF4

Secretome analysis of mesenchymal stem cell factors fostering oligodendroglial differentiation of neural stem cells in vivo - Agrelo, Iria Samper; Schira-Heinen, Jessica; Beyer, Felix; Groh, Janos; Bütermann, Christine; Estrada, Veronica; Poschmann, Gereon; Bribian, Ana; Jadasz, Janusz J.; Lopez-Mascaraque, Laura; Kremer, David; Martini, Rudolf; et al. (International Journal of Molecular Sciences, 2020)
Mesenchymal stem cell (MSC)-secreted factors have been shown to significantly promote oligodendrogenesis from cultured primary adult neural stem cells (aNSCs) and oligodendroglial precursor cells (OPCs). Revealing underlying mechanisms of how aNSCs can be fostered to differentiate into a specific cell lineage could provide important insights for the establishment of novel neuroregenerative treatment approaches aiming at myelin repair. However, the nature of MSC-derived differentiation and maturation factors acting on the oligodendroglial lineage has not been identified thus far. In addition to missing information on active ingredients, the degree to which MSC-dependent lineage instruction is functional in vivo also remains to be established. We here demonstrate that MSC-derived factors can indeed stimulate oligodendrogenesis and myelin sheath generation of aNSCs transplanted into different rodent central nervous system (CNS) regions, and furthermore, we provide insights into the underlying mechanism on the basis of a comparative mass spectrometry secretome analysis. We identified a number of secreted proteins known to act on oligodendroglia lineage differentiation. Among them, the tissue inhibitor of metalloproteinase type 1 (TIMP-1) was revealed to be an active component of the MSC-conditioned medium, thus validating our chosen secretome approach.
CRIS-Team Scopus Importer:2020-06-26
Keywords: Glial fate modulation; Mesenchymal stem cells; Myelin; Neural stem cells; Oligodendroglia; Secretome; Spinal cord; TIMP-1; Transplantation

Secrets to a healthy Sox life: Lessons for melanocytes. - Wegner, Michael (Pigment Cell Research, 2005)
Sox proteins are transcriptional regulators with a high-mobility-group domain as sequence-specific DNA-binding domain. For function, they generally require other transcription factors as partner proteins. Sox proteins furthermore affect DNA topology and may shape the conformation of enhancer-bound multiprotein complexes as architectural proteins. Recent studies suggest that Sox proteins are tightly regulated in their expression by many signalling pathways, and that their transcriptional activity is subject to post-translational modification and sequestration mechanisms. Sox proteins are thus ideally suited to perform their many different functions as transcriptional regulators throughout mammalian development. Their unique properties also cause Sox proteins to escape detection in many standard transcription assays. In melanocytes, studies have so far focused on the Sox10 protein which functions both during melanocyte specification and at later times in the melanocyte lineage. During specification, Sox10 activates the Mitf gene as the key regulator of melanocyte development. At later stages, it ensures cell-type specific expression of melanocyte genes such as Dopachrome tautomerase. Both activities require cooperation with transcriptional partner proteins such as Pax-3, CREB and eventually Mitf. If predictions can be made from other cell lineages, further functions of Sox proteins in melanocytes may still lie ahead. Copyright © Blackwell Munksgaard 2005.
UnivIS-Import:2015-03-09:Pub.2005.med.IB.LPCIPDBI.secret
Keywords: Bending; Co-activator; High-mobility-group; Mitf; Sry; Transcription factor

Selection and Characterization of Tau Binding ᴅ-Enantiomeric Peptides with Potential for Therapy of Alzheimer Disease - Dammers, Christina; Yolcu, Deniz; Kukuk, Laura; Willbold, Dieter; Pickhardt, Marcus; Mandelkow, Eckhard; Horn, Anselm; Sticht, Heinrich; Malhis, Marwa Nidal; Will, Nadja; Schuster, Judith; Funke, Susanne Aileen (PLoS ONE, 2016)
A variety of neurodegenerative disorders, including Alzheimer disease (AD), are associated with neurofibrillary tangles composed of the tau protein, as well as toxic tau oligomers. Inhibitors of pathological tau aggregation, interrupting tau self-assembly, might be useful for the development of therapeutics. Employing mirror image phage display with a large peptide library (over 109 different peptides), we have identified tau fibril binding peptides consisting of d-enantiomeric amino acids. d-enantiomeric peptides are extremely protease stable and not or less immunogenic than l-peptides, and the suitability of d-peptides for in vivo applications have already been demonstrated. Phage display selections were performed using fibrils of the d-enantiomeric hexapeptide VQIVYK, representing residues 306 to 311 of the tau protein, as a target. VQIVYK has been demonstrated to be important for fibril formation of the full lengths protein and forms fibrils by itself. Here, we report on d-enantiomeric peptides, which bind to VQIVYK, tau isoforms like tau3RD (K19) as well as to full lengths tau fibrils, and modulate the aggregation of the respective tau form. The peptides are able to penetrate cells and might be interesting for therapeutic and diagnostic applications in AD research.
EVALuna2:33727

Selective Biodetection Platform for Melanoma Diagnosis Using Functionalized THz Metamaterials - Richter, Merle; Loth, Yannik; Wigger, Anna K.; Rachinger, Nicole; Nordhoff, Daniela; Stock, Daniel; Boßerhoff, Anja Katrin; Bolivar, Peter Haring (International Conference on Infrared, Millimeter, and Terahertz Waves, IRMMW-THz, 2023)
In this contribution, we propose a promising diagnostic platform for various biosensing tasks. More precisely, we demonstrate its capabability of selective and sensitive detection of the early growth response protein 2 (EGR2). This protein is a transcription factor, which is found in increased activities in melanoma cells. The analysis was performed with the proposed THz biosensor on a complex sample of nucleus proteins. Categorically, the sensor belongs to the frequency selective surface type metamaterials and is composed of an array unit cells, each containing an asymmetric double split ring resonator. The single resonator elements are slits in a metallic layer and are enhanced by an undercut etch. This enables the active area of the sensor to be functionalized selectively. On one sensor chip, multiple query fields containing the metamaterial array are located, thereby enabling internal referencing and multiple analyses to take place in one measurement sequence.
CRIS-Team Scopus Importer:2023-12-08

Selective expression of sense and antisense transcripts of the sushi-ichi-related retrotransposon - derived family during mouse placentogenesis - Henke, Christine; Strissel, Pamela; Schubert, Maria-Theresa; Mitchell, Megan; Stolt, Claus; Faschingbauer, Florian; Beckmann, Matthias; Strick, Reiner (Retrovirology, 2015)
LTR-retrotransposons became functional neogenes through evolution by acquiring promoter sequences, regulatory elements and sequence modification. Mammalian retrotransposon transcripts (Mart1-9), also called sushi-ichi-related retrotransposon-homolog (SIRH) genes, are a class of Ty3/gypsy LTR-retroelements showing moderate homology to the sushi-ichi LTR-retrotransposon in pufferfish. Rtl1/Mart1 and Peg10/Mart2 expression in mouse placenta and demonstration of their functional roles during placental development exemplifies their importance in cellular processes. In this study, we analyzed all eleven mouse Mart genes from the blastocyst stage and throughout placentogenesis in order to gain information about their expression and regulation.Quantitative PCR, in situ hybridization (ISH) and immunoblotting showed various expression patterns of the 11 mouse Mart genes through different placental stages. Zcchc5/Mart3, Zcchc16/ Mart4 and Rgag1/Mart9 expression was undetectable. Rtl1/Mart1, Peg10/Mart2, Rgag4/Mart5 - Cxx1a,b,c/Mart8b,c,a gene expression was very low at the blastocyst stage. Later placental stages showed an increase of expression for Rtl1/Mart1, Rgag4/Mart5 - Cxx1a,b,c/Mart8b,c,a, the latter up to 1,489 molecules/ng cDNA at E9.5. From our recently published findings Peg10/Mart2 was the most highly expressed Mart gene. ISH demonstrated sense and antisense transcript co-localization of Rgag4/Mart5 to Cxx1a,b,c/Mart8b,c,a in trophoblast subtypes at the junctional zone, with an accumulation of antisense transcripts in the nuclei. To validate these results, we developed a TAG-aided sense/antisense transcript detection (TASA-TD) method, which verified sense and antisense transcripts for Rtl1/Mart1, Rgag4/Mart5 - Cxx1a,b,c/Mart8b,c,a. Except for Rtl1/Mart1 and Cxx1a,b/Mart8b,c all other Mart genes showed a reduced amount of antisense transcripts. Northern blot and 5' and 3' RACE confirmed both sense and antisense transcripts for Ldoc1/Mart7 and Cxx1a,b,c/Mart8b,c,a. Immunoblotting demonstrated a single protein throughout all placental stages for Ldoc1/Mart7, but for Cxx1a,b,c/Mart8b,c,a a switch occurred from a 57 kDa protein at E10.5 and E14.5 to a 25 kDa protein at E16.5 and E18.5.RNA and protein detection of mouse Mart genes support neo-functionalization of retrotransposons in mammalian genomes. Undetectable expression of Zcchc5/Mart3, Zcchc16/Mart4 and Rgag1/Mart9 indicate no role during mouse placentogenesis. Rgag4/Mart5 to Cxx1a,b,c/Mart8b,c,a gene expression support a role for differentiation from the ectoplacental cone. Mart antisense transcripts and protein alterations predict unique and complex molecular regulation in a time directed manner throughout mouse placentogenesis.
EVALuna2:4979

Selenium-binding protein 1 is down-regulated in malignant melanoma - Schott, Mandy; de Jel, Miriam Martha; Engelmann, Julia C.; Renner, Philipp; Geissler, Edward K.; Boßerhoff, Anja Katrin; Kuphal, Silke (Oncotarget, 2018)
Selenium-binding protein 1 (SELENBP1) expression is reduced in various epithelial cancer entities compared to corresponding normal tissue and has already been described as a tumor suppressor involved in the regulation of cell proliferation, senescence, migration and apoptosis. We identified SELENBP1 to be down-regulated in cutaneous melanoma, a malignant cancer of pigment-producing melanocytes in the skin, which leads to the assumption that SELENBP1 also functions as tumor suppressor in the skin, as shown by others e.g. for prostate or lung carcinoma. However, in vitro analyses indicate that SELENBP1 re-expression in human melanoma cell lines has no impact on cell proliferation, migration or tube formation of the tumor cells themselves when compared to control-transfected cells. Interestingly, supernatant taken from melanoma cell lines transfected with a SELENBP1 re-expression plasmid led to suppression of vessel formation of HMEC cells. Furthermore, SELENBP1 re-expression alters the sensitivity of melanoma cells for Vemurafenib treatment. The data also hint to a functional interaction of SELENBP1 with GPX1 (Glutathione peroxidase 1). Low SELENBP1 mRNA levels correlate inversely with GPX1 expression in melanoma. The re-expression of SELENBP1 combined with down-regulation of GPX1 expression led to reduction of the proliferation of melanoma cells. In summary, SELENBP1 influences the tumor microenvironment and SELENBP1 action is functionally influenced by GPX1.
EVALuna2:34070

Sequential requirement of Sox4 and Sox11 during development of the sympathetic nervous system. - Wegner, Michael; Sock, Elisabeth; et al. (Development, 2010)
The highly related transcription factors Sox4 and Sox11 are expressed in the developing sympathetic nervous system. In the mouse, Sox11 appears first, whereas Sox4 is prevalent later. Using mouse mutagenesis and overexpression strategies in chicken, we studied the role of both SoxC proteins in this tissue. Neither Sox4 nor Sox11 predominantly functioned by promoting pan-neuronal or noradrenergic differentiation of sympathetic neurons as might have been expected from studies in neuronal precursors of the central nervous system. The transcriptional network that regulates the differentiation of sympathetic neurons remained intact and expression of noradrenergic markers showed only minor alterations. Instead, Sox11 was required in early sympathetic ganglia for proliferation of tyrosine hydroxylase-expressing cells, whereas Sox4 ensured the survival of these cells at later stages. In the absence of both Sox4 and Sox11, sympathetic ganglia remained hypoplastic throughout embryogenesis because of consecutive proliferation and survival defects. As a consequence, sympathetic ganglia were rudimentary in the adult and sympathetic innervation of target tissues was impaired leading to severe dysautonomia. © 2010. Published by The Company of Biologists Ltd.
UnivIS-Import:2015-03-09:Pub.2010.med.IB.LPCIPDBI.sequen
Keywords: Apoptosis; Chicken; Conditional mutagenesis; Mouse; Noradrenergic differentiation; Proliferation; Sympathoadrenal lineage

'Shared-Hook' and 'Changed-Hook' Binding Activities of Herpesviral Core Nuclear Egress Complexes Identified by Random Mutagenesis - Lösing, Josephine; Haege, Sigrun; Schütz, Martin; Wagner, Sabrina; Wardin, Julia; Sticht, Heinrich; Marschall, Manfred (Cells, 2022)
Herpesviruses replicate their genomes and assemble their capsids in the host cell nucleus. To progress towards morphogenesis in the cytoplasm, herpesviruses evolved the strategy of nuclear egress as a highly regulated process of nucleo-cytoplasmic capsid transition. The process is conserved among alpha-, beta- and gamma-herpesviruses and involves the formation of a core and multicomponent nuclear egress complex (NEC). Core NEC is assembled by the interaction between the nucleoplasmic hook protein, i.e., pUL53 (human cytomegalovirus, HCMV), and the integral membrane-associated groove protein, i.e., pUL50. Our study aimed at the question of whether a panherpesviral NEC scaffold may enable hook-into-groove interaction across herpesviral subfamilies. For this purpose, NEC constructs were generated for members of all three subfamilies and analyzed for multi-ligand interaction using a yeast two-hybrid (Y2H) approach with randomized pUL53 mutagenesis libraries. The screening identified ten library clones displaying cross-viral shared hook-into-groove interaction. Interestingly, a slightly modified Y2H screening strategy provided thirteen further changed-hook pUL53 clones having lost parental pUL50 interaction but gained homolog interaction. In addition, we designed a sequence-predicted hybrid construct based on HCMV and Epstein-Barr virus (EBV) core NEC proteins and identified a cross-viral interaction phenotype. Confirmation was provided by applying protein-protein interaction analyses in human cells, such as coimmunoprecipitation settings, confocal nuclear rim colocalization assays, and HCMV Delta UL53 infection experiments with pUL53-complementing cells. Combined, the study provided the first examples of cross-viral NEC interaction patterns and revealed a higher yield of human cell-confirmed binding clones using a library exchange rate of 3.4 than 2.7. Thus, the study provides improved insights into herpesviral NEC protein binding specificities of core NEC formation. This novel information might be exploited to gain a potential target scaffold for the development of broadly acting NEC-directed inhibitory small molecules.
CRIS-Team WoS Importer:2023-01-27

Simiate and the focal adhesion kinase FAK1 cooperate in the regulation of dendritogenesis - Rama, Ramya; Derlig, Kristin; Vießmann, Nina; Gossmann, Roman; Oriold, Fabian; Gießl, Andreas; Brandstätter, Johann Helmut; Enz, Ralf; Dahlhaus, Regina (Scientific Reports, 2022)
Despite the crucial importance of dendritogenesis for the correct functioning of neurons, the molecular mechanisms underlying neuronal arborisation are still not well understood. Current models suggest that distinct parts and phases of dendritic development are regulated by the expression of distinct transcription factors, that are able to target the cytoskeleton. Two proteins recently implicated in dendritogenesis are the Focal Adhesion Kinase FAK1 and the Actin-binding protein Simiate. Using heterologous expression systems as well as mouse brain extracts in combination with coprecipitation assays, we show that Simiate is able to associate with FAK1. Differential centrifugation experiments further revealed the interaction to be present in cytosolic as well as nuclear fractions. Inside the nucleus though, Simiate preferentially binds to a FAK1 isoform of 80 kDa, which has previously been shown to regulate transcription factor activity. Investigating the function of both proteins in primary hippocampal cultures, we further found that FAK1 and Simiate have distinct roles in dendritogenesis: While FAK1 increases dendrite length and number, Simiate preferentially enhances growth and branching. However, if being confined to the nucleus, Simiate selectively triggers primary dendrite formation, enhancing transcription activity at the same time. Since the effect on primary dendrites is specifically re-normalized by a co-expression of FAK1 and Simiate in the nucleus, the data implies that the two proteins interact to counterbalance each other in order to control dendrite formation. Looking at the role of the cytosolic interaction of FAK1 and Simiate, we found that neurotrophin induced dendritogenesis causes a striking colocalisation of FAK1 and Simiate in dendritic growth cones, which is not present otherwise, thus suggesting that the cytosolic interaction stimulates growth cone mediated dendritogenesis in response to certain external signals. Taken together, the data show that FAK1 and Simiate exert several and distinct actions during the different phases of dendritogenesis and that these actions are related to their subcellular localisation and their interaction.
CRIS-Team Scopus Importer:2022-07-15

Simiate is an Actin binding protein involved in filopodia dynamics and arborization of neurons - Derlig, Kristin; Ehrhardt, Toni; Giessi, Andreas; Brandstätter, Johann Helmut; Enz, Ralf; Dahlhaus, Regina (Frontiers in Cellular Neuroscience, 2014)
The Actin cytoskeleton constitutes the functional base for a multitude of cellular processes extending from motility and migration to cell mechanics and morphogenesis. The latter is particularly important to neuronal cells since the accurate functioning of the brain crucially depends on the correct arborization of neurons, a process that requires the formation of several dozens to hundreds of dendritic branches. Recently, a model was proposed where different transcription factors are detailed to distinct facets and phases of dendritogenesis and exert their function by acting on the Actin cytoskeleton, however, the proteins involved as well as the underlying molecular mechanisms are largely unknown. Here, we demonstrate that Simiate, a protein previously indicated to activate transcription, directly associates with both, G- and F-Actin and in doing so, affects Actin polymerization and Actin turnover in living cells. Imaging studies illustrate that Simiate particularly influences filopodia dynamics and specifically increases the branching of proximal, but not distal dendrites of developing neurons. The data suggests that Simiate functions as a direct molecular link between transcription regulation on one side, and dendritogenesis on the other, wherein Simiate serves to coordinate the development of proximal and distal dendrites by acting on the Actin cytoskeleton of filopodia and on transcription regulation, hence supporting the novel model.
EVALuna2:4699

Single expressed glycine receptor domains reconstitute functional ion channels without subunit-specific desensitization behavior - Meiselbach, Heike; Vogel, Nico; Langlhofer, Georg; Stangl, Sabine; Schleyer, Barbara; Bahnassawy, Lamia'A; Sticht, Heinrich; Breitinger, Hans-Georg; Becker, Cord-Michael; Villmann, Carmen (Journal of Biological Chemistry, 2014)
Cys loop receptors are pentameric arrangements of independent subunits that assemble into functional ion channels. Each subunit shows a domain architecture. Functional ion channels can be reconstituted even from independent, nonfunctional subunit domains, as shown previously for GlyR?1 receptors. Here, we demonstrate that this reconstitution is not restricted to ?1 but can be transferred to other members of the Cys loop receptor family. A nonfunctional GlyR subunit, truncated at the intracellular TM3-4 loop by a premature stop codon, can be complemented by co-expression of the missing tail portion of the receptor. Compared with ?1 subunits, rescue by domain complementation was less efficient when GlyR?3 or the GABAA/C subunit ?1 was used. If truncation disrupted an alternative splicing cassette within the intracellular TM3-4 loop of ?3 subunits, which also regulates receptor desensitization, functional rescue was not possible. When ?3 receptors were restored by complementation using domains with and without the spliced insert, no difference in desensitization was found. In contrast, desensitization properties could even be transferred between ?1/?3 receptor chimeras harboring or lacking the ?3 splice cassette proving that functional rescue depends on the integrity of the alternative splicing cassette in ?3. Thus, an intact ?3 splicing cassette in the TM3-4 loop environment is indispensable for functional rescue, and the quality of receptor restoration can be assessed from desensitization properties.
EVALuna2:4694

SiRNA-Knockdown einer neuen Argonaute2 Spleißvariante verringert die tumorigenen Eigenschaften von Melanomzellen. - Linck, Lisa; Boßerhoff, Anja Katrin (JOURNAL DER DEUTSCHEN DERMATOLOGISCHEN GESELLSCHAFT, 2018)
EVALuna2:203603

Site-specific formation of Maillard, oxidation, and condensation products from whey proteins during reaction with lactose - Meltretter, Jasmin; Seeber, Silke; Humeny, Andreas; Becker, Cord-Michael; Pischetsrieder, Monika (Journal of Agricultural and Food Chemistry, 2007)
Heat treatment of dairy products leads to structural changes of proteins, which can severely decrease the nutritional value [Mauron, J. J. Nutr. Sci. Vitaminol. (Tokyo) 1990, 36(Suppl. 1), S57-69]. In this study, model solutions of the two main whey proteins, α-lactalbumin and β-lactoglobulin, respectively, were incubated with lactose, and modifications were monitored by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). Lactulosyl residues were the most abundant modifications of α-lactalbumin and β-lactoglobulin. Up to four of these adducts were identified on the proteins. Enzymatical digest with endoproteinase AspN prior to mass spectrometric analysis allowed the detection of further modifications and their localization in the amino acid sequence. Most prominent modifications were lactulosyllysine, Nε-carboxymethyllysine, oxidation of lysine to aminoadipic semialdehyde, oxidation of methionine to methionine sulfoxide, cyclization of N-terminal glutamic acid to a pyrrolidone, and oxidation of cysteine or tryptophan. The presence of methionine oxidation was deduced from a control protein that had been oxidized by hydrogen peroxide. These studies establish MALDI-TOF-MS as a reliable tool to monitor chemical modifications of nutritional proteins during food processing. © 2007 American Chemical Society.
UnivIS-Import:2015-03-09:Pub.2007.nat.dchph.llmch.sitesp
Keywords: α-lactalbumin; β-lactoglobulin; Glycation; Maillard reaction; Matrix-assisted laser desorption/ionization mass spectrometry; Milk; Oxidation; Site specific

Smaller, Stronger, More Stable: Peptide Variants of a SARS-CoV-2 Neutralizing Miniprotein - Weißenborn, Lucas; Richel, Elie; Hueseman, Helena; Welzer, Julia; Beck, Silvan; Schäfer, Simon; Sticht, Heinrich; Überla, Klaus; Eichler, Jutta (International Journal of Molecular Sciences, 2022)
Based on the structure of a de novo designed miniprotein (LCB1) in complex with the receptor binding domain (RBD) of the SARS-CoV-2 spike protein, we have generated and characterized truncated peptide variants of LCB1, which present only two of the three LCB1 helices, and which fully retained the virus neutralizing potency against different SARS-CoV-2 variants of concern (VOC). This antiviral activity was even 10-fold stronger for a cyclic variant of the two-helix peptides, as compared to the full-length peptide. Furthermore, the proteolytic stability of the cyclic peptide was substantially improved, rendering it a better potential candidate for SARS-CoV-2 therapy. In a more mechanistic approach, the peptides also served as tools to dissect the role of individual mutations in the RBD for the susceptibility of the resulting virus variants to neutralization by the peptides. As the peptides reported here were generated through chemical synthesis, rather than recombinant protein expression, they are amenable to further chemical modification, including the incorporation of a wide range of non-proteinogenic amino acids, with the aim to further stabilize the peptides against proteolytic degradation, as well as to improve the strength, as well the breadth, of their virus neutralizing capacity.
CRIS-Team WoS Importer:2022-06-24
Keywords: SARS-CoV-2; virus; peptides; structure-based design; synthetic peptides; peptide mimics

Small ubiquitin-related modifier (SUMO) pathway-mediated enhancement of human cytomegalovirus replication correlates with a recruitment of SUMO-1/3 proteins to viral replication compartments - Scherer, Myriam; Reuter, Nina; Wagenknecht, Nadine; Otto, Victoria; Sticht, Heinrich; Stamminger, Thomas (Journal of General Virology, 2013)
Recent studies have suggested that the small ubiquitin-related modifier (SUMO) conjugation pathway may play an important role in intrinsic antiviral resistance and thus for repression of herpesviral infections. In particular, it was shown that the herpes simplex virus type-1 regulatory protein ICP0 acts as a SUMO-targeted ubiquitin ligase (STUbL), inducing the widespread degradation of SUMO-conjugated proteins during infection. As the IE1 protein of human cytomegalovirus (HCMV) is known to mediate a de-SUMOylation of PML, we investigated whether HCMV uses a similar mechanism to counteract intrinsic antiviral resistance. We generated primary human fibroblasts stably expressing FLAG-SUMO-1 or FLAG-SUMO-3 and analysed the SUMOylation pattern after HCMV infection or isolated IE1 expression. However, Western blot experiments did not reveal a global loss of SUMO conjugates, either in HCMV-infected or in IE1-expressing cells, arguing against a function of IE1 as an STUbL. Interestingly, we observed that FLAG-SUMO-1 and FLAG-SUMO-3, subsequent to IE1-mediated promyelocytic leukemia protein (PML) de-SUMOylation and the consequent disruption of PML nuclear bodies, were recruited into viral replication compartments. This raised the question of whether FLAG-SUMO-1/3 might promote HCMV replication. Intriguingly, overexpression of FLAG-SUMO-1/3 enhanced accumulation of viral DNA, which correlated with an increase in viral replication and in virus particle release. Together, these data indicate that HCMV, in contrast to other herpesviruses, has evolved subtle mechanisms enabling it to utilize the SUMO conjugation pathway for its own benefit, resulting in an overall positive effect of SUMO conjugation for HCMV replication.
EVALuna2:8191

Soluble CD83 improves and accelerates wound healing by the induction of pro-resolving macrophages - Royzman, Dmytro; Peckert-Maier, Katrin; Stich, Lena; König, Christina; Wild, Andreas; Tauchi, Miyuki; Ostalecki, Christian; Kiesewetter, Franklin; Seyferth, Stefan; Lee, Geoffrey; Eming, Sabine A.; Fuchs, Maximilian; et al. (Frontiers in Immunology, 2022)
To facilitate the recovery process of chronic and hard-to-heal wounds novel pro-resolving treatment options are urgently needed. We investigated the pro-regenerative properties of soluble CD83 (sCD83) on cutaneous wound healing, where sCD83 accelerated wound healing not only after systemic but also after topical application, which is of high therapeutic interest. Cytokine profile analyses revealed an initial upregulation of inflammatory mediators such as TNFα and IL-1β, followed by a switch towards pro-resolving factors, including YM-1 and IL-10, both expressed by tissue repair macrophages. These cells are known to mediate resolution of inflammation and stimulate wound healing processes by secretion of growth factors such as epidermal growth factor (EGF) and vascular endothelial growth factor (VEGF), which promote vascularization as well as fibroblast and keratinocyte differentiation. In conclusion, we have found strong wound healing capacities of sCD83 beyond the previously described role in transplantation and autoimmunity. This makes sCD83 a promising candidate for the treatment of chronic- and hard-to-heal wounds.
CRIS-Team Scopus Importer:2022-10-28
Keywords: CD83; macrophages; stem cells; therapy; tissue regeneration; wound healing

Solution structure of the autophagy-related protein LC3C reveals a polyproline II motif on a mobile tether with phosphorylation site - Krichel, Carsten; Möckel, Christina; Schillinger, Oliver; Huesgen, Pitter F.; Sticht, Heinrich; Strodel, Birgit; Weiergräber, Oliver H.; Willbold, Dieter; Neudecker, Philipp (Scientific Reports, 2019)
(Macro-)autophagy is a compartmental degradation pathway conserved from yeast to mammals. The yeast protein Atg8 mediates membrane tethering/hemifusion and cargo recruitment and is essential for autophagy. The human MAP1LC3/GABARAP family proteins show high sequence identity with Atg8, but MAP1LC3C is distinguished by a conspicuous amino-terminal extension with unknown functional significance. We have determined the high-resolution three-dimensional structure and measured the backbone dynamics of MAP1LC3C by NMR spectroscopy. From Ser18 to Ala120, MAP1LC3C forms an α-helix followed by the ubiquitin-like tertiary fold with two hydrophobic binding pockets used by MAP1LC3/GABARAP proteins to recognize targets presenting LC3-interacting regions (LIRs). Unlike other MAP1LC3/GABARAP proteins, the amino-terminal region of MAP1LC3C does not form a stable helix α1 but a "sticky arm" consisting of a polyproline II motif on a flexible linker. Ser18 at the interface between this linker and the structural core can be phosphorylated in vitro by protein kinase A, which causes additional conformational heterogeneity as monitored by NMR spectroscopy and molecular dynamics simulations, including changes in the LIR-binding interface. Based on these results we propose that the amino-terminal polyproline II motif mediates specific interactions with the microtubule cytoskeleton and that Ser18 phosphorylation modulates the interplay of MAP1LC3C with its various target proteins.
CRIS-Team Scopus Importer:2019-10-15

SomethiNG 2 talk about-Transcriptional regulation in embryonic and adult oligodendrocyte precursors - Küspert, Melanie; Wegner, Michael (Brain Research, 2016)
Glial cells that express the chondroitin sulfate proteoglycan NG2 represent an inherently heterogeneous population. These so-called NG2-glia are present during development and in the adult CNS, where they are referred to as embryonic oligodendrocyte precursors and adult NG2-glia, respectively. They give rise to myelinating oligodendrocytes at all times of life. Over the years much has been learnt about the transcriptional network in embryonic oligodendrocyte precursors, and several transcription factors from the HLH, HMG-domain, zinc finger and homeodomain protein families have been identified as main constituents. Much less is known about the corresponding network in adult NG2-glia. Here we summarize and discuss current knowledge on functions of each of these transcription factor families in NG2-glia, and where possible compare transcriptional regulation in embryonic oligodendrocyte precursors and adult NG2-glia. This article is part of a Special Issue entitled SI:NG2-glia (Invited only).
EVALuna2:4984

Sox10, a novel transcriptional modulator in glial cells - Sock, Elisabeth; Wegner, Michael; et al. (Journal of Neuroscience, 1998)
Sox proteins are characterized by possession of a DNA-binding domain with similarity to the high-mobility group domain of the sex determining factor SRY. Here, we report on Sox10, a novel protein with predominant expression in glial cells of the nervous system. During development Sox10 first appeared in the forming neural crest and continued to be expressed as these cells contributed to the forming PNS and finally differentiated into Schwann cells. In the CNS, Sox10 transcripts were originally confined to glial precursors and later detected in oligodendrocytes of the adult brain. Functional studies failed to reveal autonomous transcriptional activity for Sox10. Instead, Sox10 functioned synergistically with the POU domain protein Tst-1/Oct6/SCIP with which it is coexpressed during certain stages of Schwann cell development. Synergy depended on binding to adjacent sites in target promoters, was mediated by the N-terminal regions of both proteins, and could not be observed between Sox10 and several other POU domain proteins. Interestingly, Sox10 also modulated the function of Pax3 and Krox-20, two other transcription factors involved in Schwann cell development. We propose a role for Sox10 in conferring cell specificity to the function of other transcription factors in developing and mature gila.
UnivIS-Import:2015-03-05:Pub.1998.med.IB.LPCIPDBI.sox10a
Keywords: Neural crest; Oligodendrocyte; POU; Schwann cell; Sox; Synergy

Sox10 cooperates with the mediator subunit 12 during terminal differentiation of myelinating glia - Vogl, Michael; Reiprich, Simone; Küspert, Melanie; Kosian, Thomas; Schrewe, Heinrich; Nave, Klaus-Armin; Wegner, Michael (The Journal of Neuroscience, 2013)
Several transcription factors are essential for terminal differentiation of myelinating glia, among them the high-mobility-group-domain-containing protein Sox10. To better understand how these factors exert their effects and shape glial expression programs, we identified and characterized a physical and functional link between Sox10 and the Med12 subunit of the Mediator complex that serves as a conserved multiprotein interphase between transcription factors and the general transcription machinery. We found that Sox10 bound with two of its conserved domains to the C-terminal region of Med12 and its close relative, Med12-like. In contrast to Med12-like, substantial amounts of Med12 were detected in both Schwann cells and oligodendrocytes. Its conditional glia-specific deletion in mice led to terminal differentiation defects that were highly reminiscent of those obtained after Sox10 deletion. In support of a functional cooperation, both proteins were jointly required for Krox20 induction and were physically associated with the critical regulatory region of the Krox20 gene in myelinating Schwann cells. We conclude that Sox10 functions during terminal differentiation of myelinating glia, at least in part by Med12-dependent recruitment of the Mediator complex.
EVALuna2:4941

Sox10 is an active nucleocytoplasmic shuttle protein, and shuttling is crucial for Sox10-mediated transactivation - Wegner, Michael; Stamminger, Thomas; Glaser, Gabriele; et al. (Molecular and Cellular Biology, 2002)
Sox10 belongs to a family of transcription regulators characterized by a DNA-binding domain known as the HMG box. It plays fundamental roles in neural crest development, peripheral gliogenesis, and terminal differentiation of oligodendrocytes. In accord with its function as transcription factor, Sox10 contains two nuclear localization signals and is most frequently detected in the nucleus. In this study, we report that Sox10 is an active nucleocytoplasmic shuttle protein, competent of both entering and exiting the nucleus. We identified a functional Rev-type nuclear export signal within the DNA-binding domain of Sox10. Mutational inactivation of this nuclear export signal or treatment of cells with the CRM1-specific export inhibitor leptomycin B inhibited nuclear export and consequently nucleocytoplasmic shuttling of Sox10. Importantly, the inhibition of the nuclear export of Sox10 led to decreased transactivation of transfected reporters and endogenous target genes, arguing that continuous nucleocytoplasmic shuttling is essential for the function of Sox10. To our knowledge this is the first time that nuclear export has been reported and shown to be functionally relevant for any Sox protein.
UnivIS-Import:2015-03-09:Pub.2002.med.IB.LPCIPDBI.sox10i

Sox10 is required for Schwann-cell homeostasis and myelin maintenance in the adult peripheral nerve. - Fröb, Franziska; Kichko, Tetyana; Reeh, Peter; Wegner, Michael; et al. (Glia, 2011)
The transcription factor Sox10 functions during multiple consecutive stages of Schwann-cell development in the peripheral nervous system (PNS). Although Sox10 continues to be expressed in mature Schwann cells of the adult peripheral nerve, it is currently unclear whether it is still functional. Here, we used a genetic strategy to selectively delete Sox10 in glia of adult mice in a tamoxifen-dependent manner. The tamoxifen-treated mice developed a severe peripheral neuropathy that was associated with dramatic alterations in peripheral nerve structure and function. Demyelination and axonal degeneration were as much evident as signs of neuroinflammation. Compound action potentials exhibited pathophysiological alterations. Sox10-deleted Schwann cells persisted in the peripheral nerve, but did not exhibit a mature, myelinating phenotype arguing that Sox10 is rather required for differentiation and maintenance of the differentiated state than for survival. Our report is the first evidence that Sox10 is still essentially required for Schwann-cell function in the adult PNS and establishes a useful model in which to study human peripheral neuropathies. © 2011 Wiley-Liss, Inc..
UnivIS-Import:2015-03-09:Pub.2011.med.IB.LPCIPDBI.sox10i
Keywords: Charcot-Marie-Tooth disease; Conditional mouse mutagenesis; Glia; High-mobility-group; Myelin; Peripheral neuropathy; Sry; Transcriptional control

Sox10 is required for Schwann cell identity and progression beyond the immature Schwann cell stage. - Wegner, Michael; et al. (The Journal of Cell Biology, 2010)
Mutations in the transcription factor SOX10 cause neurocristopathies, including Waardenburg-Hirschsprung syndrome and peripheral neuropathies in humans. This is partly attributed to a requirement for Sox10 in early neural crest for survival, maintenance of pluripotency, and specification to several cell lineages, including peripheral glia. As a consequence, peripheral glia are absent in Sox10-deficient mice. Intriguingly, Sox10 continues to be expressed in these cells after specification. To analyze glial functions after specification, we specifically deleted Sox10 in immature Schwann cells by conditional mutagenesis. Mutant mice died from peripheral neuropathy before the seventh postnatal week. Nerve alterations included a thinned perineurial sheath, increased lipid and collagen deposition, and a dramatically altered cellular composition. Nerve conduction was also grossly aberrant, and neither myelinating nor non-myelinating Schwann cells formed. Instead, axons of different sizes remained unsorted in large bundles. Schwann cells failed to develop beyond the immature stage and were unable to maintain identity. Thus, our study identifies a novel cause for peripheral neuropathies in patients with SOX10 mutations. © 2010 Finzsch et al.
UnivIS-Import:2015-03-09:Pub.2010.med.IB.LPCIPDBI.sox10i

SOX10 mutations in patients with Waardenburg-Hirschsprung disease - Wegner, Michael; et al. (Nature Genetics, 1998)
Waardenburg syndrome (WS; deafness with pigmentary abnormalities) and Hirschsprung's disease (HSCR; aganglionic megacolon) are congenital disorders caused by defective function of the embryonic neural crest1,2. WS and HSCR are associated in patients with Waardenburg-Shah syndrome (WS4), whose symptoms are reminiscent of the white coat-spotting and aganglionic megacolon displayed by the mouse mutants Dom (Dominant megacolon), piebald-lethal (s(l)) and lethal spotting (ls). The s(l) and ls phenotypes are caused by mutations in the genes encoding the Endothelin-B receptor (Ednrb) and Endothelin 3 (Edn3), respectively. The identification of Sox10 as the gene mutated in Dom mice (B.H. et al., manuscript submitted) prompted us to analyse the role of its human homologue SOX10 in neural crest defects. Here we show that patients from four families with WS4 have mutations in SOX10, whereas no mutation could be detected in patients with HSCR alone. These mutations are likely to result in haploinsufficiency of the SOX10 product. Our findings further define the locus heterogeneity of Waardenburg- Hirschsprung syndromes, and point to an essential role of SOX10 in the development of two neural crest-derived human cell lineages.
UnivIS-Import:2015-03-05:Pub.1998.med.IB.LPCIPDBI.sox10m

Sox10 promotes the formation and maintenance of giant congenital nevus and melanoma. - Wegner, Michael; et al. (Nature Cell Biology, 2012)
UnivIS-Import:2015-03-09:Pub.2012.med.IB.LPCIPDBI.sox10p

Sox10 regulates ciliary neurotrophic factor gene expression in Schwann cells. - Wegner, Michael; et al. (Proceedings of the National Academy of Sciences of the United States of America, 2006)
Ciliary neurotrophic factor (Cntf) plays an essential role in postnatal maintenance of spinal motoneurons. Whereas the expression of this neurotrophic factor is low during embryonic development, it is highly up-regulated after birth in myelinating Schwann cells of rodents. To characterize the underlying transcriptional mechanisms, we have analyzed and compared the effects of various glial transcription factors. In contrast to Pit-1, Oct-1, Unc-86 homology region (POU) domain class 3, transcription factor 1 (Oct6/SCIP/Tst-1) and paired box gene 3 (Pax3), SRY-box-containing gene 10 (Sox10) induces Cntf expression in Schwann cells. Subsequent promoter analysis using luciferase reporter gene and EMSA identified the corresponding response elements within the Cntf promoter. Overexpression of Sox10 in primary sciatic nerve Schwann cells leads to a > 100-fold up-regulation of Cntf protein, and suppression of Sox10 by RNA interference in the spontaneously immortalized Schwann cell line 32 reduces Cntf expression by > 80%. Mice with heterozygous inactivation of the Sox10 gene show significantly reduced Cntf protein levels in sciatic nerves, indicating that Sox10 is necessary and sufficient for regulating Cntf expression in the peripheral nervous system. © 2006 by The National Academy of Sciences of the USA.
UnivIS-Import:2015-03-09:Pub.2006.med.IB.LPCIPDBI.sox10r
Keywords: Hirschsprung disease; Neuropathy; Oct6; Pax3; Promoter

SOX10 structure function analysis in the chicken reveals important insights into its role in human neurocristopathies. - Müller, Jana; Wegner, Michael; et al. (Human Molecular Genetics, 2010)
UnivIS-Import:2015-03-09:Pub.2010.med.IB.LPCIPDBI.sox10s

SOX11 and SOX4 drive the reactivation of an embryonic gene program during murine wound repair - Miao, Qi; Hill, Matthew C.; Chen, Fengju; Mo, Qianxing; Ku, Amy T.; Ramos, Carlos; Sock, Elisabeth; Lefebvre, Véronique; Nguyen, Hoang (Nature Communications, 2019)
Tissue injury induces changes in cellular identity, but the underlying molecular mechanisms remain obscure. Here, we show that upon damage in a mouse model, epidermal cells at the wound edge convert to an embryonic-like state, altering particularly the cytoskeletal/extracellular matrix (ECM) components and differentiation program. We show that SOX11 and its closest relative SOX4 dictate embryonic epidermal state, regulating genes involved in epidermal development as well as cytoskeletal/ECM organization. Correspondingly, postnatal induction of SOX11 represses epidermal terminal differentiation while deficiency of Sox11 and Sox4 accelerates differentiation and dramatically impairs cell motility and re-epithelialization. Amongst the embryonic genes reactivated at the wound edge, we identify fascin actin-bundling protein 1 (FSCN1) as a critical direct target of SOX11 and SOX4 regulating cell migration. Our study identifies the reactivated embryonic gene program during wound repair and demonstrates that SOX11 and SOX4 play a central role in this process.
CRIS-Team Scopus Importer:2019-09-17

Sox11 gene disruption causes congenital anomalies of the kidney and urinary tract (CAKUT). - Neirijnck, Yasmine; Reginensi, Antoine; Renkema, Kirsten Y.; Massa, Filippo; Kozlov, Vladimir M.; Dhib, Haroun; Bongers, Ernie M. H. F.; Feitz, Wout F.; Van Eerde, Albertien M.; Lefebvre, Veronique; Knoers, Nine V. A. M.; Tabatabaei, Mansoureh; et al. (Kidney International, 2018)
Congenital abnormalities of the kidney and the urinary tract (CAKUT) belong to the most common birth defects in human, but the molecular basis for the majority of CAKUT patients remains unknown. Here we show that the transcription factor SOX11 is a crucial regulator of kidney development. SOX11 is expressed in both mesenchymal and epithelial components of the early kidney anlagen. Deletion of Sox11 in mice causes an extension of the domain expressing Gdnf within rostral regions of the nephrogenic cord and results in duplex kidney formation. On the molecular level SOX11 directly binds and regulates a locus control region of the protocadherin B cluster. At later stages of kidney development, SOX11 becomes restricted to the intermediate segment of the developing nephron where it is required for the elongation of Henle's loop. Finally, mutation analysis in a cohort of patients suffering from CAKUT identified a series of rare SOX11 variants, one of which interferes with the transactivation capacity of the SOX11 protein. Taken together these data demonstrate a key role for SOX11 in normal kidney development and may suggest that variants in this gene predispose to CAKUT in humans.
UnivIS-Import:2018-09-05:Pub.2018.med.IB.LPCIPDBI.sox11g
Keywords: CAKUT; duplex kidneys; kidney induction; nephron; Sox11

Sox11 is an Activity-Regulated Gene with Dentate-Gyrus-Specific Expression Upon General Neural Activation - von Wittgenstein, Julia; Zheng, Fang; Wittmann, Marie-Theres; Balta, Elli-Anna; Ferrazzi, Fulvia; Schäffner, Iris; Häberle, Benjamin; Valero Aracama, Maria Jesus; Koehl, Muriel; Miranda, Carlos J.; Kaspar, Brian K.; Ekici, Arif Bülent; et al. (Cerebral Cortex, 2020)
Neuronal activity initiates transcriptional programs that shape long-term changes in plasticity. Although neuron subtypes differ in their plasticity response, most activity-dependent transcription factors (TFs) are broadly expressed across neuron subtypes and brain regions. Thus, how region- and neuronal subtype-specific plasticity are established on the transcriptional level remains poorly understood. We report that in young adult (i.e., 6-8 weeks old) mice, the developmental TF SOX11 is induced in neurons within 6 h either by electroconvulsive stimulation or by exploration of a novel environment. Strikingly, SOX11 induction was restricted to the dentate gyrus (DG) of the hippocampus. In the novel environment paradigm, SOX11 was observed in a subset of c-FOS expressing neurons (ca. 15%); whereas around 75% of SOX11+ DG granule neurons were c-FOS+, indicating that SOX11 was induced in an activity-dependent fashion in a subset of neurons. Environmental enrichment or virus-mediated overexpression of SOX11 enhanced the excitability of DG granule cells and downregulated the expression of different potassium channel subunits, whereas conditional Sox11/4 knock-out mice presented the opposite phenotype. We propose that Sox11 is regulated in an activity-dependent fashion, which is specific to the DG, and speculate that activity-dependent Sox11 expression may participate in the modulation of DG neuron plasticity.
CRIS-Team Scopus Importer:2020-05-29
Keywords: dentate gyrus; hippocampus; immediate early gene; plasticity; Sox11

Sox11 regulates survival and axonal growth of embryonic sensory neurons. - Sock, Elisabeth; Wegner, Michael; et al. (Developmental Dynamics, 2011)
Sensory neurons transduce various stimuli including temperature, pain, and touch from the periphery to the central nervous system. Sensory neuron development is governed by a combination of extracellular cues and specific gene expression. We demonstrated that the transcription factor Sox11 was highly expressed in the developing sensory neurons. To test the function of Sox11, we used a knockin mouse model where the entire coding region of Sox11 was replaced by a LacZ reporter. The ablation of Sox11 caused severe reduction in sensory neuron survival in the trigeminal and dorsal root ganglia, although it did not affect migration of neural crest cells or acquisition of major sensory neuron subtypes. We further demonstrated that ablating Sox11 caused an arrest of axonal outgrowth in vivo and in vitro. This defect could not be fully rescued by blocking cell death. Our data suggest that Sox11 is a key regulator of sensory neuron development. © 2010 Wiley-Liss, Inc.
UnivIS-Import:2015-03-09:Pub.2011.med.IB.LPCIPDBI.sox11r
Keywords: Apoptosis; Axonal growth; Developing embryo; Peripheral nervous system; Sensory neuron; Sox11; Transcription factor

Sox12 deletion in the mouse reveals non-reciprocal redundancy with the related Sox4 and Sox11 transcription factors. - Wegner, Michael; Sock, Elisabeth; et al. (2008)
UnivIS-Import:2015-03-09:Pub.2008.med.IB.LPCIPDBI.sox12d

Sox13 functionally complements the related Sox5 and Sox6 as important developmental modulators in mouse spinal cord oligodendrocytes - Baroti, Tina; Schillinger, Anja; Wegner, Michael; Stolt, Claus (Journal of Neurochemistry, 2016)
The role of transcription factor Sox13, which together with Sox5 and Sox6 belongs to the SoxD family, is only poorly characterized in central nervous system development. Therefore, we analysed whether Sox13 expression and function overlaps with or differs from that of its close relatives Sox5 and Sox6. In the developing mouse spinal cord, we found Sox13 predominantly expressed in neuroepithelial precursors, oligodendroglial and astroglial cells. The substantially overlapping expression with Sox5 and Sox6 in oligodendroglial cells prompted us to study potential roles during specification, lineage progression and differentiation of oligodendrocytes. In contrast to Sox5 and Sox6, Sox13 expression continues after differentiation and even increases in myelinating oligodendrocytes. Sox13 deletion did not interfere with oligodendroglial development, which was normal in Sox13-deficient mice. However, the premature differentiation of oligodendrocyte precursors triggered by loss of Sox6 was slightly more prominent in Sox6/Sox13 double-deficient mice. Sox13 can bind to the same sites in myelin gene promoters as Sox5 and Sox6 in vitro. Reporter gene assays furthermore reveal a similar antagonizing effect on Sox10-dependent transactivation of myelin gene promoters as previously shown for Sox5 and Sox6. This argues that Sox13 is functionally redundant with the other SoxD proteins and complements Sox5 and Sox6 in their role as important modulators of oligodendrocyte development. The transcription factor Sox13 is co-expressed with the related Sox5 and Sox6 in cells of the oligodendroglial lineage. By itself, it has little impact on oligodendrocyte development but supports Sox5 and Sox6 during the process as a functionally redundant transcription factor.
EVALuna2:4987

Sox21-transcriptional Regulation in malignant Melanoma - Rachinger, N.; Boßerhoff, Anja Katrin; Kuphal, Silke (JOURNAL DER DEUTSCHEN DERMATOLOGISCHEN GESELLSCHAFT, 2021)
CRIS-Team WoS Importer:2021-09-24

Sox2: A multitasking networker. - Reiprich, Simone; Wegner, Michael (Neurogenesis, 2014)
UnivIS-Import:2018-09-05:Pub.2014.med.IB.LPCIPDBI.sox2am

Sox5 controls dorsal progenitor and interneuron specification in the spinal cord - Quiroga, Alejandra C.; Stolt, Claus; Diez Del Corral, Ruth; Dimitrov, Spas; Perez-Alcala, Siro; Sock, Elisabeth; Barbas, Julio A.; Wegner, Michael; Morales, Aixa V. (Developmental Neurobiology, 2015)
The basic organization of somatosensory circuits in the spinal cord is already setup during the initial patterning of the dorsal neural tube. Extrinsic signals, such as Wnt and TGF-? pathways, activate combinatorial codes of transcription factors that are responsible for generating a pattern of discrete domains of dorsal progenitors (dp). These progenitors will give rise to distinct dorsal interneurons (dI). The Wnt/ ?catenin signaling pathway controls specification of dp/dI1-3 progenitors and interneurons. According to the current model in the field, Wnt/?catenin activity seems to act in a graded fashion in the spinal cord, as different relative levels determine the identity of adjacent progenitors. However, it is not clear how this activity gradient is controlled and how the identities of dI1-3 are differentially regulated by Wnt signalling. We have determined that two SoxD transcription factors, Sox5 and Sox6, are expressed in restricted domains of dorsal progenitors in the neural tube. Using gain- and loss-of function approaches in chicken embryos, we have established that Sox5 controls cell fate specification of dp2 and dp3 progenitors and, as a result, controls the correct number of the corresponding dorsal interneurons (dI2 and dI3). Furthermore, Sox5 exerts its function by restricting dorsally Wnt signaling activity via direct transcriptional induction of the negative Wnt pathway regulator Axin2. By that way, Sox5 acts as a Wnt pathway modulator that contributes to sharpen the dorsal gradient of Wnt/?catenin activity to control the distinction of two functionally distinct types of interneurons, dI2 and dI3 involved in the somatosensory relay.
EVALuna2:4962

Sox8 and Sox10 jointly maintain myelin gene expression in oligodendrocytes. - Turnescu, Tanja; Arter, Juliane; Reiprich, Simone; Tamm, Ernst R.; Reiprich, Simone; Waisman, Ari; Wegner, Michael (Glia, 2018)
In Schwann cells of the vertebrate peripheral nervous system, induction of myelination and myelin maintenance both depend on the HMG-domain-containing transcription factor Sox10. In oligodendrocytes of the central nervous system, Sox10 is also essential for the induction of myelination. Its role in late phases of myelination and myelin maintenance has not been studied so far. Here, we show that these processes are largely unaffected in mice that lack Sox10 in mature oligodendrocytes. As Sox10 is co-expressed with the related Sox8, we also analyzed oligodendrocytes and myelination in Sox8-deficient mice. Again, we could not detect any major abnormalities. Expression of many myelin genes was only modestly reduced in both mouse mutants. Dramatic reductions in expression levels and phenotypic disturbances became only apparent once Sox8 and Sox10 were both absent. This argues that Sox8 and Sox10 are jointly required for myelin maintenance and impact myelin gene expression. One direct target gene of both Sox proteins is the late myelin gene Mog. Our results point to at least partial functional redundancy between both related Sox proteins in mature oligodendrocytes and are the first report of a substantial function of Sox8 in the oligodendroglial lineage.
EVALuna2:33476
Keywords: glia; HMG; myelin; oligodendrocyte; Sox; Sry

Sox8 is a specific marker for muscle satellite cells and inhibits myogenesis - Wegner, Michael; Glaser, Gabriele; et al. (Journal of Biological Chemistry, 2003)
Sox8 belongs to a family of transcription regulators characterized by a unique DNA-binding domain known as the high mobility group box. Many Sox proteins play fundamental roles in vertebrate development and differentiation processes. Expression of Sox8 is strong during embryonic muscle development and gradually declines postnatally. In this study, we report that in adult skeletal muscle Sox8 is confined to satellite cells. Down-regulation during myogenic differentiation was also detected in cell culture systems and occurred in parallel with down-regulation of the related Sox9. Overexpression of Sox8 or Sox9 on the other hand disrupted myoblasts in their ability to form myotubes. Concomitantly, expression of MyoD and myogenin decreased and basal as well as MyoD-induced activities of the myogenin promoter were strongly reduced in a Sox8-dependent manner. Our data suggest that Sox8 acts as a specific negative regulator of skeletal muscle differentiation, possibly by interfering with the function of myogenic basic helix-loop-helix proteins.
UnivIS-Import:2015-03-09:Pub.2003.med.IB.LPCIPDBI.sox8is

Sox9 and Sox10 influence survival and migration of oligodendrocyte precursors in the spinal cord by regulating PDGF receptor alpha expression. - Stolt, Claus; Wegner, Michael; et al. (Development, 2008)
Specification of the myelin-forming oligodendrocytes of the central nervous system requires the Sox9 transcription factor, whereas terminal differentiation depends on the closely related Sox10. Between specification and terminal differentiation, Sox9 and Sox1O are co-expressed in oligodendrocyte precursors and are believed to exert additional functions. To identify such functions, we have deleted Sox9 specifically in already specified oligodendrocyte precursors of the spinal cord. In the absence of Sox9, oligodendrocyte precursors developed normally and started terminal differentiation on schedule. However, when Sox10 was additionally deleted, oligodendrocyte precursors exhibited an altered migration pattern and were present in reduced numbers because of increased apoptosis rates. Remaining precursors continued to express many characteristic oligodendroglial markers. Aberrant expression of astrocytic and neuronal markers was not observed. Strikingly, we failed to detect PDGF receptor a expression in the mutant oligodendrocyte precursors, arguing that PDGF receptor α is under transcriptional control of Sox9 and Sox10. Altered PDGF receptor α expression is furthermore sufficient to explain the observed phenotype, as PDGF is both an important survival factor and migratory cue for oligodendrocyte precursors. We thus conclude that Sox9 and Sox10 are required in a functionally redundant manner in oligodendrocyte precursors for PDGF-dependent survival and migration.
UnivIS-Import:2015-03-09:Pub.2008.med.IB.LPCIPDBI.sox9an
Keywords: Glia; High-mobility group; PDGF; Redundancy; SoxE; Sry; Transgenic mice

SOX9 controls epithelial branching by activating RET effector genes during kidney development. - Sock, Elisabeth; Wegner, Michael; et al. (Human Molecular Genetics, 2011)
Congenital abnormalities of the kidney and urinary tract are some of the most common defects detected in the unborn child. Kidney growth is controlled by the GDNF/RET signalling pathway, but the molecular events required for the activation of RET downstream targets are still poorly understood. Here we show that SOX9, a gene involved in campomelic dysplasia (CD) in humans, together with its close homologue SOX8, plays an essential role in RET signalling. Expression of SOX9 can be found from the earliest stages of renal development within the ureteric tip, the ureter mesenchyme and in a segment-specific manner during nephrogenesis. Using a tissue-specific knockout approach, we show that, in the ureteric tip, SOX8 and SOX9 are required for ureter branching, and double-knockout mutants exhibit severe kidney defects ranging from hypoplastic kidneys to renal agenesis. Further genetic analysis shows that SOX8/9 are required downstream of GDNF signalling for the activation of RET effector genes such as Sprouty1 and Etv5. At later stages of development, SOX9 is required to maintain ureteric tip identity and SOX9 ablation induces ectopic nephron formation. Taken together, our study shows that SOX9 acts at multiple steps during kidney organogenesis and identifies SOX8 and SOX9 as key factors within the RET signalling pathway. Our results also explain the aetiology of kidney hypoplasia found in a proportion of CD patients. © The Author 2011. Published by Oxford University Press. All rights reserved.
UnivIS-Import:2015-03-09:Pub.2011.med.IB.LPCIPDBI.sox9co

Sox9 in the developing central nervous system: A jack of all trades? - Vogel, Julia; Wegner, Michael (Neural Regeneration Research, 2021)
CRIS-Team Scopus Importer:2020-11-06

SOX9 is expressed in human fetal prostate epithelium and enhances prostate cancer invasion. - Wegner, Michael; et al. (Cancer Research, 2008)
SOX9 is a transcription factor that plays a critical role in the development of multiple tissues. We previously reported that SOX9 in normal human adult prostate was restricted to basal epithelium. SOX9 was also expressed in a subset of prostate cancer (PCa) cells and was increased in relapsed hormone-refractory PCa. Moreover, SOX9 expression in PCa cell lines enhanced tumor cell proliferation and was β-catenin regulated. Here we report additional in vivo results showing that SOX9 is highly expressed during fetal prostate development by epithelial cells expanding into the mesenchyme, suggesting it may contribute to invasive growth in PCa. Indeed, SOX9 overexpression in LNCaP PCa xenografts enhanced growth, angiogenesis, and invasion. Conversely, short hairpin RNA-mediated SOX9 suppression inhibited the growth of CWR22Rv1 PCa xenografts. These results support important functions of SOX9 in both the development and maintenance of normal prostate, and indicate that these functions contribute to PCa tumor growth and invasion. ©2008 American Association for Cancer Research.
UnivIS-Import:2015-03-09:Pub.2008.med.IB.LPCIPDBI.sox9is

Sox9 overexpression exerts multiple stage-dependent effects on mouse spinal cord development - Vogel, Julia; Weider, Matthias; Engler, Lisa; Hillgärtner, Simone; Schmitt, Christian; Hermans-Borgmeyer, Irm; Wegner, Michael (Glia, 2019)
The high-mobility-group (HMG)-domain protein Sox9 is one of few transcription factors implicated in gliogenesis in the vertebrate central nervous system. To further study the role of Sox9 in early spinal cord development, we generated a mouse that allows expression of Sox9 in a temporally and spatially controlled manner. Using this mouse, we show that premature Sox9 expression in neural precursor cells disrupted the neuroepithelium of the ventricular zone. Sox9 also compromised development and survival of neuronal precursors and neurons. Additionally, we observed in these mice substantial increases in oligodendroglial and astroglial cells. Reversing the normal order of appearance of essential transcriptional regulators during oligodendrogenesis, Sox10 preceded Olig2. Our study reinforces the notion that Sox9 has a strong gliogenic activity. It also argues that Sox9 expression has to be tightly controlled to prevent negative effects on early spinal cord structure and neuronal development.
CRIS-Team WoS Importer:2019-11-26

Sox9-overexpression promotes gliogenesis at the expense of neurogenesis in the embryonic mouse spinal cord - Vogel, Julia; Weider, Matthias; Wegner, Michael (GLIA, 2019)
CRIS-Team WoS Importer:2020-01-10

Sox9 regulates melanocytic fate decision of adult hair follicle stem cells - Stüfchen, Isabel; Beyer, Felix; Stäbler, Sebastian; Fischer, Stefan; Kappelmann, Melanie; Beckervordersandforth, Ruth; Boßerhoff, Anja Katrin (iScience, 2023)
The bulge of hair follicles harbors Nestin+ (neural crest like) stem cells, which exhibit the potential to generate various cell types including melanocytes. In this study, we aimed to determine the role of Sox9, an important regulator during neural crest development, in melanocytic differentiation of those adult Nestin+ cells. Immunohistochemical analysis after conditional Sox9 deletion in Nestin+ cells of adult mice revealed that Sox9 is crucial for melanocytic differentiation of these cells and that Sox9 acts as a fate determinant between melanocytic and glial fate. A deeper understanding of factors that regulate fate decision, proliferation and differentiation of these stem cells provides new aspects to melanoma research as melanoma cells share many similarities with neural crest cells. In summary, we here show the important role of Sox9 in melanocytic versus glial fate decision of Nestin+ stem cells in the skin of adult mice.
CRIS-Team Scopus Importer:2023-06-16
Keywords: Cell biology; Developmental biology; Molecular biology

SOX after SOX: SOXession regulates neurogenesis. - Wegner, Michael (Genes & Development, 2011)
Vertebrate embryonic stem (ES) cells give rise to many different cell types in multistep processes. These involve the establishment of a competent state, specification, differentiation, and maturation, and often involve Sox transcription factors. In this issue of Genes & Development, Bergsland and colleagues (pp. 2453-2464) determine the genome-wide binding profile of Sox2, Sox3, and Sox11 as ES cells become specified to neural precursors and differentiate into neurons. An ordered, sequential binding of these Sox proteins to a common set of gene enhancers was found to drive neurogenesis, as Sox proteins first help to preselect neural genes in ES cells and later ensure their proper activation in neural precursors or neurons. © 2011 by Cold Spring Harbor Laboratory Press.
UnivIS-Import:2015-03-09:Pub.2011.med.IB.LPCIPDBI.soxaft
Keywords: Lineage formation; Neural development; Neural stem cells; Sox genes

Sox appeal - Sox10 attracts epigenetic and transcriptional regulators in myelinating glia - Weider, Matthias; Reiprich, Simone; Wegner, Michael (Biological Chemistry, 2013)
Sox10 belongs to the Sox family of high-mobility group-box transcription factors. It fulfils widespread and essential functions in myelinating glia at multiple stages of development such as glial specification, survival and terminal differentiation. To a large extent, these diverse activities can be attributed to its capacity to interact with different transcription factors in distinct regulatory networks. Beyond transcription factors, an increasing number of interaction partners are emerging with alternative impact on gene expression. These include components of the mediator complex, the Brahma-associated factor complex and histone deacetylases. Here, we discuss interactions with functional relevance in myelinating glia and link Sox10 function in these cells not only to gene transcription, but also to epigenetics and chromatin remodeling.
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SoxC transcription factors are required for neuronal differentiation in adult hippocampal neurogenesis. - Wegner, Michael; Sock, Elisabeth; Lie, Dieter Chichung; et al. (Journal of Neuroscience, 2012)
Neural stem cells (NSCs) generate new hippocampal dentate granule neurons throughout adulthood. The genetic programs controlling neuronal differentiation of adult NSCs are only poorly understood. Here we show that, in the adult mouse hippocampus, expression of the SoxC transcription factors Sox4 and Sox11 is initiated around the time of neuronal commitment of adult NSCs and is maintained in immature neurons. Overexpression of Sox4 and Sox11 strongly promotes in vitro neurogenesis from adult NSCs, whereas ablation of Sox4/Sox11 prevents in vitro and in vivo neurogenesis from adult NSCs. Moreover, we demonstrate that SoxC transcription factors target the promoters of genes that are induced on neuronal differentiation of adult NSCs. Finally, we show that reprogramming of astroglia into neurons is dependent on the presence of SoxC factors. These data identify SoxC proteins as essential contributors to the genetic network controlling neuronal differentiation in adult neurogenesis and neuronal reprogramming of somatic cells. © 2012 the authors.
UnivIS-Import:2015-03-09:Pub.2012.med.IB.LPCIPDBI.soxctr

SoxC transcription factors: multifunctional regulators of neurodevelopment - Kavyanifar, Atria; Turan, Sören; Lie, Dieter Chichung (Cell and Tissue Research, 2018)
During development, generation of neurons is coordinated by the sequential activation of gene expression programs by stage- and subtype-specific transcription factor networks. The SoxC group transcription factors, Sox4 and Sox11, have recently emerged as critical components of this network. Initially identified as survival and differentiation factors for neural precursors, SoxC factors have now been linked to a broader array of developmental processes including neuronal subtype specification, migration, dendritogenesis and establishment of neuronal projections, and are now being employed in experimental strategies for neuronal replacement and axonal regeneration in the diseased central nervous system. This review summarizes the current knowledge regarding SoxC factor function in CNS development and disease and their promise for regeneration.
EVALuna2:34133

SoxD proteins influence multiple stages of oligodendrocyte development and modulate SoxE protein function. - Sock, Elisabeth; Wegner, Michael; Stolt, Claus; et al. (Developmental Cell, 2006)
The myelin-forming oligodendrocytes are an excellent model to study transcriptional regulation of specification events, lineage progression, and terminal differentiation in the central nervous system. Here, we show that the group D Sox transcription factors Sox5 and Sox6 jointly and cell-autonomously regulate several stages of oligodendrocyte development in the mouse spinal cord. They repress specification and terminal differentiation and influence migration patterns. As a consequence, oligodendrocyte precursors and terminally differentiating oligodendrocytes appear precociously in spinal cords deficient for both Sox proteins. Sox5 and Sox6 have opposite functions than the group E Sox proteins Sox9 and Sox10, which promote oligodendrocyte specification and terminal differentiation. Both genetic as well as molecular evidence suggests that Sox5 and Sox6 directly interfere with the function of group E Sox proteins. Our studies reveal a complex regulatory network between different groups of Sox proteins that is essential for proper progression of oligodendrocyte development. © 2006 Elsevier Inc. All rights reserved.
UnivIS-Import:2015-03-09:Pub.2006.med.IB.LPCIPDBI.soxdpr
Keywords: DEVBIO

SoxD transcription factor deficiency in Schwann cells delays myelination in the developing peripheral nervous system - Ittner, Ella; Hartwig, Anna; Elsesser, Olga; Wüst, Hannah; Fröb, Franziska; Wedel, Miriam; Schimmel, Margit; Tamm, Ernst R.; Wegner, Michael; Sock, Elisabeth (Scientific Reports, 2021)
The three SoxD proteins, Sox5, Sox6 and Sox13, represent closely related transcription factors with important roles during development. In the developing nervous system, SoxD proteins have so far been primarily studied in oligodendroglial cells and in interneurons of brain and spinal cord. In oligodendroglial cells, Sox5 and Sox6 jointly maintain the precursor state, interfere with terminal differentiation, and thereby ensure the proper timing of myelination in the central nervous system. Here we studied the role of SoxD proteins in Schwann cells, the functional counterpart of oligodendrocytes in the peripheral nervous system. We show that Schwann cells express Sox5 and Sox13 but not Sox6. Expression was transient and ceased with the onset of terminal differentiation. In mice with early Schwann cell-specific deletion of both Sox5 and Sox13, embryonic Schwann cell development was not substantially affected and progressed normally into the promyelinating stage. However, there was a mild and transient delay in the myelination of the peripheral nervous system of these mice. We therefore conclude that SoxD proteins—in stark contrast to their action in oligodendrocytes—promote differentiation and myelination in Schwann cells.
CRIS-Team Scopus Importer:2021-07-16

SoxE factors: Transcriptional regulators of neural differentiation and nervous system development. - Weider, Matthias; Wegner, Michael (Seminars in Cell & Developmental Biology, 2017)
Sox8, Sox9 and Sox10 represent the three vertebrate members of the SoxE subclass of high-mobility-group domain containing Sox transcription factors. They play important roles in the peripheral and central nervous systems as regulators of stemness, specification, survival, lineage progression, glial differentiation and homeostasis. Functions are frequently overlapping, but sometimes antagonistic. SoxE proteins dynamically interact with transcriptional regulators, chromatin changing complexes and components of the transcriptional machinery. By establishing regulatory circuits with other transcription factors and microRNAs, SoxE proteins perform divergent functions in several cell lineages of the vertebrate nervous system, and at different developmental stages in the same cell lineage. The underlying molecular mechanisms are the topic of this review.<br
EVALuna2:33486
Keywords: Brain; Glia; Neural crest; Oligodendrocyte; Schwann cell; Transcriptional network

SoxE function in vertebrate nervous system development. - Stolt, Claus; Wegner, Michael (International Journal of Biochemistry & Cell Biology, 2010)
Sox8, Sox9, and Sox10 as transcription factors of subgroup E of the Sox protein family are essential for many aspects of nervous system development. These SoxE proteins are already required for the initial neural crest induction, but also guarantee survival and maintenance of pluripotency in migrating neural crest stem cells. SoxE proteins are furthermore key regulators of glial specification in both the peripheral and the central nervous systems. At later stages of development, Sox10 plays crucial roles in Schwann cells and oligodendrocytes for terminal differentiation and myelin formation. In both glial cell types, Sox10 controls directly the expression of genes encoding the major myelin proteins. SoxE proteins are well-integrated components of regulatory networks and as such modulated in their activity by cooperating or antagonistic transcription factors such as SoxD or various bHLH proteins. The multiple functions in peripheral and central nervous system development also link SoxE proteins to various human diseases and identify these proteins as promising targets of future therapeutic approaches. © 2009 Elsevier Ltd. All rights reserved.
UnivIS-Import:2015-03-09:Pub.2010.med.IB.LPCIPDBI.soxefu
Keywords: Astrocyte; Differentiation; Oligodendrocyte; Schwann cell; Specification

SoxE proteins are differentially required in mouse adrenal gland development. - Reiprich, Simone; Stolt, Claus; Wegner, Michael; et al. (Molecular Biology of the Cell, 2008)
Sry-box (Sox)8, Sox9, and Sox10 are all strongly expressed in the neural crest. Here, we studied the influence of these closely related transcription factors on the developing adrenal medulla as one prominent neural crest derivative. Whereas Sox9 was not expressed, both Sox8 and Sox10 occurred widely in neural crest cells migrating to the adrenal gland and in the gland itself, and they were down-regulated in cells expressing catecholaminergic traits. Sox10-deficient mice lacked an adrenal medulla. The adrenal anlage was never colonized by neural crest cells, which failed to specify properly at the dorsal aorta and died apoptotically during migration. Furthermore, mutant neural crest cells did not express Sox8. Strong adrenal phenotypes were also observed when the Sox10 dimerization domain was inactivated or when a transactivation domain in the central portion was deleted. Sox8 in contrast had only minimal influence on adrenal gland development. Phenotypic consequences became only visible in Sox8-deficient mice upon additional deletion of one Sox10 allele. Replacement of Sox10 by Sox8, however, led to significant rescue of the adrenal medulla, indicating that functional differences between the two related Sox proteins contribute less to the different adrenal phenotypes of the null mutants than dependence of Sox8 expression on Sox10. © 2008 by The American Society for Cell Biology.
UnivIS-Import:2015-03-09:Pub.2008.med.IB.LPCIPDBI.soxepr

Sp2 is the only glutamine-rich Specificity protein with minor impact on development and differentiation in myelinating glia. - Wegener, Amelie; Küspert, Melanie; Sock, Elisabeth; Philipsen, Sjaak; Suske, Guntram; Wegner, Michael (Journal of Neurochemistry, 2017)
Oligodendrocytes and Schwann cells are the myelinating glia of the vertebrate nervous system and by generation of myelin sheaths allow rapid saltatory conduction. Previous in vitro work had pointed to a role of the zinc finger containing specificity proteins Sp1 and Sp3 as major regulators of glial differentiation and myelination. Here, we asked whether such a role is also evident in vivo using mice with specific deletions of Sp1 or Sp3 in myelinating glia. We also studied glia-specific conditional Sp2- and constitutive Sp4-deficient mice to include all related glutamine-rich Sp factors into our analysis. Surprisingly, we did not detect developmental Schwann cell abnormalities in any of the mutant mice. Oligodendrocyte development and differentiation was also not fundamentally affected as oligodendrocytes were present in all mouse mutants and retained their ability to differentiate and initiate myelin gene expression. The most severe defect we observed was a 50% reduction in Mbp- and proteolipid protein 1 (Plp1)-positive differentiating oligodendrocytes in Sp2 mutants at birth. Unexpectedly, glial development appeared undisturbed even in the joint absence of Sp1 and Sp3. We conclude that Sp2 has a minor effect on the differentiation of myelinating glia, and that glutamine-rich Sp proteins are not essential regulators of the process. (Figure presented.).
EVALuna2:33488
Keywords: C2H2 zinc-finger proteins; glia; myelin; oligodendrocyte; Schwann cell

SPARCL1 is an angiocrine inhibitor of tumorigenesis in colorectal carcinoma - Tenkerian, Clara; Regensburger, Daniela; Langer, Victoria; Klingler, Anika; Borau, Anne; Sticht, Heinrich; Ramming, Andreas; Wohlfahrt, Thomas; Schmid, Benjamin; Meniel, Valerie; Grützmann, Robert; Britzen-Laurent, Nathalie; et al. (CANCER RESEARCH, 2019)
CRIS-Team WoS Importer:2019-10-15

Spartin recruits PKC-ζ via the PKC-ζ interacting proteins ZIP1 and ZIP3 to lipid droplets. - Urbanczyk, Andreas; Enz, Ralf (Journal of Neurochemistry, 2011)
Protein kinase C-ζ interacting proteins (ZIP1-3) recruit the enzymatic activity of the atypical protein kinase C isoforms PKC-λ/ι or PKC-ζ to target proteins. In this study, we searched for binding partners of ZIP3 in the CNS and identified spartin, a multifunctional protein that is mutated in spastic paraplegia type 20. In transfected cells, spartin was present on the surface of lipid droplets (LD), whereas ZIP proteins appeared in intracellular speckles. In the presence of spartin, ZIP1 and ZIP3 were translocated to spartin-positive LD. This translocation was mediated by amino acids 196-393 of spartin that interacted with an N-terminal region of ZIP proteins. Furthermore, ZIP proteins interacted simultaneously with spartin and PKC-ζ, resulting in an enrichment of PKC-ζ on spartin/ZIP-labelled LD. Without spartin, neither ZIP proteins nor PKC-ζ were detected on LD. Interestingly, the presence of the spartin/ZIP/PKC-ζ complex increased LD size. This effect was most pronounced upon incorporation of the ZIP3 isoform into the trimer. Finally, we co-localized spartin, ZIP proteins and PKC-ζ in axon terminals of neurons in the mammalian retina. In summary, we describe spartin as new binding partner of the ZIP/PKC-ζ dimer that recruits PKC-ζ to LD and show that the expressed ZIP isoform regulates LD size. © 2011 The Authors. Journal of Neurochemistry © 2011 International Society for Neurochemistry.
UnivIS-Import:2015-04-14:Pub.2011.med.IB.profes_1.sparti
Keywords: lipid droplets; p62; protein kinase C-ζ interacting protein; retina; sequestosome-1 (SQSTM1); SPG20

SPATA5 mutations cause a distinct autosomal recessive phenotype of intellectual disability, hypotonia and hearing loss - Buchert, Rebecca; Nesbitt, Addie I.; Tawamie, Hasan; Krantz, Ian D.; Medne, Livija; Helbig, Ingo; Matalon, Dena R.; Reis, André; Santani, Avni; Sticht, Heinrich; Abou Jamra, Rami (Orphanet Journal of Rare Diseases, 2016)
We examined an extended, consanguineous family with seven individuals with severe intellectual disability and microcephaly. Further symptoms were hearing loss, vision impairment, gastrointestinal disturbances, and slow and asymmetric waves in the EEG. Linkage analysis followed by exome sequencing revealed a homozygous variant in SPATA5 (c.1822_1824del; p.Asp608del), which segregates with the phenotype in the family. Molecular modelling suggested a deleterious effect of the identified alterations on the protein function. In an unrelated family, we identified compound heterozygous variants in SPATA5 (c.[2081G > A];[989_991delCAA]; p.[Gly694Glu];[.Thr330del]) in a further individual with global developmental delay, infantile spasms, profound dystonia, and sensorineural hearing loss. Molecular modelling suggested an impairment of protein function in the presence of both variants.SPATA5 is a member of the ATPase associated with diverse activities (AAA) protein family and was very recently reported in one publication to be mutated in individuals with intellectual disability, epilepsy and hearing loss. Our results describe new, probably pathogenic variants in SPATA5 that were identified in individuals with a comparable phenotype. We thus independently confirm that bi-allelic pathogenic variants in SPATA5 cause a syndromic form of intellectual disability, and we delineate its clinical presentation.
EVALuna2:9313

Spatially clustering de novo variants in CYFIP2, encoding the cytoplasmic FMRP interacting protein 2, cause intellectual disability and seizures - Zweier, M.; Begemann, A.; Mcwalter, K.; Cho, M. T.; Abela, L.; Banka, S.; Behring, B.; Berger, A.; Brown, C. W.; Carneiro, M.; Chen, J.; Cooper, G. M.; et al. (EUROPEAN JOURNAL OF HUMAN GENETICS, 2019)
CRIS-Team WoS Importer:2019-10-25

Spatially clustering de novo variants in CYFIP2, encoding the cytoplasmic FMRP interacting protein 2, cause intellectual disability and seizures - Zweier, Markus; Begemann, Anais; Mcwalter, Kirsty; Cho, Megan T.; Abela, Lucia; Banka, Siddharth; Behring, Bettina; Berger, Andrea; Brown, Chester W.; Carneiro, Maryline; Chen, Jiani; Cooper, Gregory M.; et al. (European journal of human genetics, 2019)
CYFIP2, encoding the evolutionary highly conserved cytoplasmic FMRP interacting protein 2, has previously been proposed as a candidate gene for intellectual disability and autism because of its important role linking FMRP-dependent transcription regulation and actin polymerization via the WAVE regulatory complex (WRC). Recently, de novo variants affecting the amino acid p.Arg87 of CYFIP2 were reported in four individuals with epileptic encephalopathy. We here report 12 independent patients harboring a variety of de novo variants in CYFIP2 broadening the molecular and clinical spectrum of a novel CYFIP2-related neurodevelopmental disorder. Using trio whole-exome or -genome sequencing, we identified 12 independent patients carrying a total of eight distinct de novo variants in CYFIP2 with a shared phenotype of intellectual disability, seizures, and muscular hypotonia. We detected seven different missense variants, of which two occurred recurrently (p.(Arg87Cys) and p.(Ile664Met)), and a splice donor variant in the last intron for which we showed exon skipping in the transcript. The latter is expected to escape nonsense-mediated mRNA decay resulting in a truncated protein. Despite the large spacing in the primary structure, the variants spatially cluster in the tertiary structure and are all predicted to weaken the interaction with WAVE1 or NCKAP1 of the actin polymerization regulating WRC-complex. Preliminary genotype-phenotype correlation indicates a profound phenotype in p.Arg87 substitutions and a more variable phenotype in other alterations. This study evidenced a variety of de novo variants in CYFIP2 as a novel cause of mostly severe intellectual disability with seizures and muscular hypotonia.
CRIS-Team WoS Importer:2019-04-23