Org-1, the Drosophila ortholog of Tbx1, is a direct activator of known identity genes during muscle specification
Schaub C, Nagaso H, Jin H, Frasch M (2012)
Publication Status: Published
Publication Type: Journal article, Original article
Publication year: 2012
Journal
Publisher: COMPANY OF BIOLOGISTS LTD
Book Volume: 139
Pages Range: 1001-1012
Journal Issue: 5
DOI: 10.1242/dev.073890
Abstract
Members of the T-Box gene family of transcription factors are important players in regulatory circuits that generate myogenic and cardiogenic lineage diversities in vertebrates. We show that during somatic myogenesis in Drosophila, the single ortholog of vertebrate Tbx1, optomotor-blind-related-gene-1 (org-1), is expressed in a small subset of muscle progenitors, founder cells and adult muscle precursors, where it overlaps with the products of the muscle identity genes ladybird (lb) and slouch (slou). In addition, org-1 is expressed in the lineage of the heart-associated alary muscles. org-1 null mutant embryos lack Lb and Slou expression within the muscle lineages that normally co-express org-1. As a consequence, the respective muscle fibers and adult muscle precursors are either severely malformed or missing, as are the alary muscles. To address the mechanisms that mediate these regulatory interactions between Org-1, Lb and Slou, we characterized distinct enhancers associated with somatic muscle expression of lb and slou. We demonstrate that these lineage-and stage-specific cis-regulatory modules (CRMs) bind Org-1 in vivo, respond to org-1 genetically and require T-box domain binding sites for their activation. In summary, we propose that org-1 is a common and direct upstream regulator of slou and lb in the developmental pathway of these two neighboring muscle lineages. Cross-repression between slou and lb and combinatorial activation of lineage-specific targets by Org-1-Slou and Org-1- Lb, respectively, then leads to the distinction between the two lineages. These findings provide new insights into the regulatory circuits that control the proper pattering of the larval somatic musculature in Drosophila.
Authors with CRIS profile
Christoph Schaub
Lehrstuhl für Entwicklungsbiologie
Hong Jin
Lehrstuhl für Entwicklungsbiologie
Manfred Frasch
Lehrstuhl für Entwicklungsbiologie
Involved external institutions
United States (USA) (US)How to cite
APA:
Schaub, C., Nagaso, H., Jin, H., & Frasch, M. (2012). Org-1, the Drosophila ortholog of Tbx1, is a direct activator of known identity genes during muscle specification. Development, 139(5), 1001-1012. https://dx.doi.org/10.1242/dev.073890
MLA:
Schaub, Christoph, et al. "Org-1, the Drosophila ortholog of Tbx1, is a direct activator of known identity genes during muscle specification." Development 139.5 (2012): 1001-1012.
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