Small GTPase involved in membrane trafficking control (By similarity). Regulates integrin internalization and recycling, but does not influence the traffic of endosomally translocated receptors in general (By similarity). As a result, may regulate cell adhesion and migration (By similarity). During the mitosis of adherent cells, controls the endosomal trafficking of integrins which is required for the successful completion of cytokinesis (By similarity). Involved in neurite growth (PubMed:19745841). Following SBF2/MTMT13-mediated activation in response to starvation-induced autophagy, binds to and regulates SNARE protein VAMP8 endolysosomal transport required for SNARE-mediated autophagosome-lysosome fusion (By similarity). Modulates protein levels of the cargo receptors TMED2 and TMED10, and required for appropriate Golgi localization of TMED10 (By similarity). Interacts with the cytoplasmic tail of integrins ITGA1, ITGA2, ITGA5, ITGA6, ITGA11 and ITGB1; this interaction is dependent upon its GDP/GTP cycle (By similarity). Interacts with RABGEF1 (via VPS9 domain) (By similarity). Interacts with ANKRD27 (By similarity). Interacts (in GTP-bound form) with VAMP8 in response to starvation; the interaction probably regulates VAMP8 endolysosomal trafficking (By similarity). Interacts (active GTP-bound form) with TMED10; the interaction is indirect and regulates TMED10 abundance and localization at the Golgi (By similarity). Colocalizes with ANKRD27 and VAMP7 in neurites (PubMed:19745841). During mitosis, in mid-telophase, localized in the ingressing cleavage furrow (By similarity). In late telophase, detected at the opposite poles of the daughter cells, in vesicles at the base of lamellipodia formed by the separating daughter cells (By similarity). Belongs to the small GTPase superfamily. Rab family.