A family of small GTP-binding proteins of the ras superfamily that control intracellular vesicle budding, cargo sorting, transport, tethering, and fusion. Different members of the family are involved in particular transport systems, e.g. rab7 is a marker of vesicles directed to endosomal/lysosomal compartments and mutations are associated with Charcot–Marie–Tooth disease type 2B. Rab11 plays a central role in plasma membrane recycling and there is a large family of rab11 interacting proteins. The rab escort protein-1 (REP1, 653 aa) is component A of rab geranylgeranyl transferase (EC 18.104.22.168), a heterodimeric enzyme (A and B subunits) that attaches a geranylgeranyl moiety to rab1A and rab3A: mutations cause choroideaemia. Rim1α (1692 aa), a rab3a-interacting molecule, is involved in long-term potentiation in the hippocampus.
Subjects: Medicine and Health.