GTP-binding protein involved in Golgi vesicle trafficking (PubMed:15356266, PubMed:34830155). May modulate vesicle budding and uncoating within the Golgi apparatus (PubMed:15356266). May recruit the lipid transfer protein VPS13 to Golgi membranes (PubMed:34830155). Recruits polyadenylate-binding protein PAB1 to COPI vesicles, and this is required for correct localization of the asymmetrically distributed ASH1 mRNA (PubMed:15356266). Interacts with RUD3 (PubMed:15356266, PubMed:15504911, PubMed:19141284, PubMed:20601958). Interacts with VPS13 (via C-terminal part); the interaction is direct (PubMed:34830155). Present with 19300 molecules/cell in log phase SD medium. Belongs to the small GTPase superfamily. Arf family.