Endosomal protein probably involved in endocytosis. Probably not involved in vacuolar trafficking. Interacts with VPS9A (PubMed:18055610). Interacts with TCTP1 (PubMed:20736351). Widely expressed. Activated by VPS9A. Although this sequence lacks the C-terminal cysteine motifs subject to isoprenylation in other Rab proteins, it does have N-terminal N-myristoylation and S-palmitoylation. Belongs to the small GTPase superfamily. Rab family.