GTPase activator for the Rho-type GTPases. As a GCM1 downstream effector, it is involved in placental development and positively regulates trophoblast cells migration. It regulates cytoskeletal remodeling by controlling the activity of Rho GTPases including RHOA, CDC42 and RAC1 (PubMed:27917469). Expressed in trophoblast cells of placental villi. Palmitoylated. Probably palmitoylated by ZDHHC3 and ZDHHC7.