Document Type
Article
Publication Date
8-15-2000
Publication Title
Proceedings of the National Academy of Sciences of the United States of America
Department
Geisel School of Medicine
Abstract
Yeast vacuoles undergo priming, docking, and homotypic fusion, although little has been known of the connections between these reactions. Vacuole-associated Vam2p and Vam6p (Vam2/6p) are components of a 65S complex containing SNARE proteins. Upon priming by Sec18p/NSF and ATP, Vam2/6p is released as a 38S subcomplex that binds Ypt7p to initiate docking. We now report that the 38S complex consists of both Vam2/6p and the class C Vps proteins [Reider, S. E. and Emr, S. D. (1997) Mol. Biol. Cell 8, 2307-2327]. This complex includes Vps33p, a member of the Sec1 family of proteins that bind t-SNAREs. We term this 38S complex HOPS, for homotypic fusion and vacuole protein sorting. This unexpected finding explains how Vam2/6p associates with SNAREs and provides a mechanistic link of the class C Vps proteins to Ypt/Rab action. HOPS initially associates with vacuole SNAREs in "cis" and, after release by priming, hops to Ypt7p, activating this Ypt/Rab switch to initiate docking.
DOI
10.1073/pnas.97.17.9402
Dartmouth Digital Commons Citation
Seals, Darren F.; Eitzen, Gary; Nathan Margolis; Wickner, William T.; and Price, Albert, "A Ypt/Rab Effector Complex Containing the Sec1 Homolog Vps33p is Required for Homotypic Vacuole Fusion" (2000). Dartmouth Scholarship. 1415.
https://digitalcommons.dartmouth.edu/facoa/1415
