Small G proteins: Arf family GTPases in vesicular transport

Abstract

Small GTP-binding proteins of the ADP-ribosylation factor (Arf) family are key components of trafficking vesicles. In the past three decades a number of vesicular carriers, whose formation depends on members of the Arf family were identified, and general molecular mechanisms how these transport carriers form and operate were established. Here we describe discovery and roles of the Arf-dependent carriers of the early secretory pathway, the COPI and COPII vesicles. We will discuss their function with regard to molecular mechanisms in coat recruitment, selection of cargo proteins, vesicle membrane budding/scission, and vesicle uncoating.