RISAP Is a TGN-Associated RAC5 Effector Regulating Membrane Traffic during Polar Cell Growth in Tobacco

Journal article


Publication Details

Author(s): Stephan O, Cottier S, Fahlen S, Montes Rodriguez A, Sun J, Eklund DM, Klahre U, Kost B
Journal: Plant Cell
Publisher: American Society of Plant Biologists
Publication year: 2014
Volume: 26
Journal issue: 11
Pages range: 4426-4447
ISSN: 1040-4651


Abstract


RAC/ROP GTPases coordinate actin dynamics and membrane traffic during polar plant cell expansion. In tobacco (Nicotiana tabacum), pollen tube tip growth is controlled by the RAC/ROP GTPase RAC5, which specifically accumulates at the apical plasma membrane. Here, we describe the functional characterization of RISAP, a RAC5 effector identified by yeast (Saccharomyces cerevisiae) two-hybrid screening. RISAP belongs to a family of putative myosin receptors containing a domain of unknown function 593 (DUF593) and binds via its DUF593 to the globular tail domain of a tobacco pollen tube myosin XI. It also interacts with F-actin and is associated with a subapical trans-Golgi network (TGN) compartment, whose cytoplasmic position at the pollen tube tip is maintained by the actin cytoskeleton. In this TGN compartment, apical secretion and endocytic membrane recycling pathways required for tip growth appear to converge. RISAP overexpression interferes with apical membrane traffic and blocks tip growth. RAC5 constitutively binds to the N terminus of RISAP and interacts in an activation-dependent manner with the C-terminal half of this protein. In pollen tubes, interaction between RAC5 and RISAP is detectable at the subapical TGN compartment. We present a model of RISAP regulation and function that integrates all these findings.



FAU Authors / FAU Editors

Kost, Benedikt Prof. Dr.
Lehrstuhl für Zellbiologie
Montes Rodriguez, Adriana
Lehrstuhl für Zellbiologie


External institutions
Ruprecht-Karls-Universität Heidelberg
Swedish University of Agricultural Sciences / Sveriges Lantbruksuniversitet (SLU)


How to cite

APA:
Stephan, O., Cottier, S., Fahlen, S., Montes Rodriguez, A., Sun, J., Eklund, D.M.,... Kost, B. (2014). RISAP Is a TGN-Associated RAC5 Effector Regulating Membrane Traffic during Polar Cell Growth in Tobacco. Plant Cell, 26(11), 4426-4447. https://dx.doi.org/10.1105/tpc.114.131078

MLA:
Stephan, Octavian, et al. "RISAP Is a TGN-Associated RAC5 Effector Regulating Membrane Traffic during Polar Cell Growth in Tobacco." Plant Cell 26.11 (2014): 4426-4447.

BibTeX: 

Last updated on 2018-10-08 at 09:39