GTP-binding protein. Can activate phospholipase D with very low efficiency. Important for normal function of the Golgi apparatus (By similarity). The GTP-bound form interacts with GOLGA1, GOLGA4 and RGPD8. The GTP-bound form directly interacts with ARFIP2; this interaction leads to an increase in the amount of bound GTP at steady state level. Binds to SCOC, preferentially in its GTP-bound form. May interact with UNC119 (By similarity). Belongs to the small GTPase superfamily. Arf family.