The function of ENSG00000100241 (SBF1, SET binding factor 1) is as follows. Acts as an adapter for the phosphatase MTMR2 to regulate MTMR2 catalytic activity and subcellular location (PubMed:12668758). Promotes the exchange of GDP to GTP, converting inactive GDP-bound Rab proteins into their active GTP-bound form (PubMed:20937701). May function as a guanine nucleotide exchange factor (GEF) activating RAB28 (PubMed:20937701). Acts as a suppressor of autophagy in neurons (PubMed:35580604). Together with its binding partner, the phosphatase MTMR2, plays a role in dephosphorylation of phosphoinositides critical for autophagy initiation and autophagosome maturation (PubMed:35580604). 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 (PubMed:9537414). {ECO:0000250|UniProtKB:Q6ZPE2, ECO:0000269|PubMed:12668758, ECO:0000269|PubMed:20937701, ECO:0000269|PubMed:35580604, ECO:0000269|PubMed:9537414}.