SBF1

Acts as an adapter for the phosphatase MTMR2 to regulate MTMR2 catalytic activity and subcellular location. Promotes the exchange of GDP to GTP, converting inactive GDP-bound Rab proteins into their active GTP-bound form. May function as a guanine nucleotide exchange factor (GEF) activating RAB28. Acts as a suppressor of autophagy in neurons. Together with its binding partner, the phosphatase MTMR2, plays a role in dephosphorylation of phosphoinositides critical for autophagy initiation and autophagosome maturation. Plays a role in positively regulating late-stage radial sorting of large caliber axons, a process leading to myelination by Schwann cells, possibly via regulating endosomal trafficking (By similarity). Inhibits myoblast differentiation in vitro and induces oncogenic transformation in fibroblasts..

Function from UniProtKB (O95248), read 2026-09-23. CC BY 4.0.