TRAPPII regulates exocytic Golgi exit by mediating nucleotide exchange on the Ypt31 ortholog RabERAB11.

ABSTRACT: The oligomeric complex transport protein particle I (TRAPPI) mediates nucleotide exchange on the RAB GTPase RAB1/Ypt1. TRAPPII is composed of TRAPPI plus three additional subunits, Trs120, Trs130, and Trs65. Unclear is whether TRAPPII mediates nucleotide exchange on RAB1/Ypt1, RAB11/Ypt31, or both. In Aspergillus nidulans, RabO(RAB1) resides in the Golgi, RabE(RAB11) localizes to exocytic post-Golgi carriers undergoing transport to the apex, and hypA encodes Trs120. RabE(RAB11), but not RabO(RAB1), immunoprecipitates contain Trs120/Trs130/Trs65, demonstrating specific association of TRAPPII with RabE(RAB11) in vivo. hypA1(ts) rapidly shifts RabE(RAB11), but not RabO(RAB1), to the cytosol, consistent with HypA(Trs120) being specifically required for RabE(RAB11) activation. Missense mutation

SUBMITTER: Pinar M 

PROVIDER: S-EPMC4394270 | biostudies-literature | 2015 Apr

REPOSITORIES: biostudies-literature