The Microtubule-Associated Rho Activating Factor GEF-H1 Interacts with Exocyst Complex to Regulate Vesicle Traffic

Ritu Pathak, Violaine D. Delorme-Walker, Michael C. Howell, Anthony N. Anselmo, Michael A. White, Gary M. Bokoch, Céline DerMardirossian

Research output: Contribution to journalArticle

41 Scopus citations

Abstract

The exocyst complex plays a critical role in targeting and tethering vesicles to specific sites of the plasma membrane. These events are crucial for polarized delivery of membrane components to the cell surface, which is critical for cell motility and division. Though Rho GTPases are involved in regulating actin dynamics and membrane trafficking, their role in exocyst-mediated vesicle targeting is not very clear. Herein, we present evidence that depletion of GEF-H1, a guanine nucleotide exchange factor for Rho proteins, affects vesicle trafficking. Interestingly, we found that GEF-H1 directly binds to exocyst component Sec5 in a Ral GTPase-dependent manner. This interaction promotes RhoA activation, which then regulates exocyst assembly/localization and exocytosis. Taken together, our work defines a mechanism for RhoA activation in response to RalA-Sec5 signaling and involvement of GEF-H1/RhoA pathway in the regulation of vesicle trafficking.

Original languageEnglish (US)
Pages (from-to)397-411
Number of pages15
JournalDevelopmental Cell
Volume23
Issue number2
DOIs
StatePublished - Aug 14 2012

    Fingerprint

ASJC Scopus subject areas

  • Molecular Biology
  • Biochemistry, Genetics and Molecular Biology(all)
  • Developmental Biology
  • Cell Biology

Cite this

Pathak, R., Delorme-Walker, V. D., Howell, M. C., Anselmo, A. N., White, M. A., Bokoch, G. M., & DerMardirossian, C. (2012). The Microtubule-Associated Rho Activating Factor GEF-H1 Interacts with Exocyst Complex to Regulate Vesicle Traffic. Developmental Cell, 23(2), 397-411. https://doi.org/10.1016/j.devcel.2012.06.014