The function of ARHGEF10, a known guanine nucleotide exchange factor (GEF) for RhoA with proposed roles in various diseases, is poorly understood. To understand the precise function of this protein, we raised a monoclonal antibody against ARHGEF10 and determined its localization in HeLa cells. ARHGEF10 was found to localize to vesicles containing Rab6, Rab8, and/or NPY-Venus in a Rab6-dependent manner. These vesicles were known to originate from the Golgi apparatus and contain secreted or membrane proteins. Ectopic expression of an N-terminal truncated ARHGEF10 mutant led to the generation of large vesicle-like structures containing both Rab6 and Rab8. On the other hand, small interfering RNA-mediated ARHGEF10 knockdown impaired the localization of Rab8 to these exocytotic vesicles. Furthermore, the invasiveness of MDA-MB231 cells was markedly decreased by knockdown of ARHGEF10, as well as of Rab8. From these results, we propose that ARHGEF10 acts in exocytosis and tumor invasion in a Rab8-dependent manner.
- Received January 29, 2016.
- Accepted August 13, 2016.
- © 2016. Published by The Company of Biologists Ltd