Premium
Purification of active HOPS complex reveals its affinities for phosphoinositides and the SNARE Vam7p
Author(s) -
Stroupe Christopher,
Collins Kevin M,
Fratti Rutilio A,
Wickner William
Publication year - 2006
Publication title -
the embo journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 7.484
H-Index - 392
eISSN - 1460-2075
pISSN - 0261-4189
DOI - 10.1038/sj.emboj.7601051
Subject(s) - rab , biology , gtpase , vacuole , microbiology and biotechnology , snare complex , protein targeting , small gtpase , effector , vacuolar protein sorting , vesicular transport proteins , lipid bilayer fusion , biochemistry , membrane , membrane protein , signal transduction , cytoplasm
Coupling of Rab GTPase activation and SNARE complex assembly during membrane fusion is poorly understood. The homotypic fusion and vacuole protein sorting (HOPS) complex links these two processes: it is an effector for the vacuolar Rab GTPase Ypt7p and is required for vacuolar SNARE complex assembly. We now report that pure, active HOPS complex binds phosphoinositides and the PX domain of the vacuolar SNARE protein Vam7p. These binding interactions support HOPS complex association with the vacuole and explain its enrichment at the same microdomains on docked vacuoles as phosphoinositides, Ypt7p, Vam7p, and the other SNARE proteins. Concentration of the HOPS complex at these microdomains may be a key factor for coupling Rab GTPase activation to SNARE complex assembly.