Probable guanine nucleotide exchange factor (GEF) which may activate RAB10. Promotes the exchange of GDP to GTP, converting inactive GDP-bound Rab proteins into their active GTP-bound form. According to PubMed:8056341, it may bind to ISRE-like element (interferon-stimulated response element) of MYC P2 promoter. Expressed ubiquitously. Highest expression in bone marrow, medium in peripheral blood lymphocytes and lowest in spleen. In brain, breast, and prostate, higher expression was seen in normal cells than in tumor cells. Expression is regulated in a growth- and cell cycle-dependent manner. Highly expressed in fetal liver. By serum in low-passage fibroblasts.