REM2 and RAB-Like Small GTPase 1 (RSG1) plays a part in targeted membrane trafficking most likely at the level of vesicle fusion with membranes. The RSG1 protein is involved in cilium biogenesis by regulating the transportation of cargo proteins to the basal body and to the apical tips of cilia. RSG1 is a potential effector of the planar cell polarity signaling pathway. RSG1 is also involved in exocytosis in secretory cells.