A COPI coat subunit interacts directly with an early-Golgi localized Arf exchange factor.

ABSTRACT: Arf (ADP-ribosylation factor) family small G proteins are crucial regulators of intracellular transport. The active GTP-bound form of Arf interacts with a set of proteins--effectors--which mediate the downstream signalling events of Arf activation. A well-studied class of Arf1 effectors comprises the coat complexes, such as the cis-Golgi-localized COPI (coat protein complex I) coat, and trans-Golgi network-endosomal clathrin coats. At least five different coats require Arf1-GTP to localize to organelle membranes. How a single Arf protein recruits different coat complexes to distinct membrane sites raises the question of how specificity is achieved. Here, we propose a molecular mechanism of this specificity for the COPI coat by showing a direct and specific interaction between a COPI subuni

SUBMITTER: Deng Y 

PROVIDER: S-EPMC2613206 | biostudies-literature | 2009 Jan

REPOSITORIES: biostudies-literature