The Ras-related superfamily of guanine nucleotide binding proteins, which includes the R-Ras, Rap, Ral/Rec and Rho/Rab subfamilies, exhibit 30-60% homology with Ras p21. Accumulating data suggests an important role for Rab proteins, either in endocytosis or in biosynthetic protein transport. The transport of newly synthesized proteins from the endoplasmic reticulum to various stacks of the Golgi complex and to secretory vesicles involves, at each stage, the movement of carrier vesicles; a process that appears to involve Rab protein function. The possibility that Rab proteins might also direct the exocytosis from secretory vesicles to the plasma membrane is supported by the observation that in yeast, the Sec4 protein, which is 40% homologous to Rab proteins, is associated with secretory vesicles. At least eight members of the Rab subfamily have been identified, each of which is found at a particular stage of a membrane transport pathway. Rab 6, also known as RAB6B, RAB6A or RAB6A, is a 208 amino acid protein that is ubiquitously expressed and is a member of the small GTPase superfamily.
Function: RAB6A belongs to the small GTPase superfamily. It may be involved in protein transport. It is a regulator of membrane traffic from the Golgi apparatus towards the endoplasmic reticulum (ER) and has a low GTPase activity.
Subunit: Interacts with CCDC64; leads to its accumulation in the pericentrosomal region (By similarity). Interacts with SCYL1BP1. Interacts with VSP52 and RABGAP1. Interacts with GCC2 (via its GRIP domain). Interacts with RAB6IP1 (via its RUN 1 domain). Isoform 1 interacts with RAB6KIFL. Isoform 2 does not interact with RAB6KIFL. Isoform 1 interacts with BICD1. Isoform 2 interacts with BICD1. Isoform 1 interacts with BICD2. Isoform 2 interacts with BICD2. Interacts with TMF1. Isoform 1 (GTP-bound) interacts with DYNLRB1; the interaction is direct. Isoform 2 (GDP-bound) interacts with DYNLRB1; the interaction is direct. Interacts with PIFO.