Search Organism: All OrganismsArabidopsis thalianaBacillus subtilis 168Bos taurusCaenorhabditis elegansCanis familiarisDanio rerioDrosophila melanogasterEquus caballusEscherichia coli K12Gallus gallusHomo sapiensMacaca mulattaMus musculusNematostella vectensisOryza sativaPan troglodytesRattus norvegicusSaccharomyces cerevisiaeSchizosaccharomyces pombeStrongylocentrotus purpuratusTakifugu rubripesXenopus laevis home help / support contribute downloads mirrors about us Mol. Biol. Cell Jun (2008); 19(6):2500-8 HOPS proofreads the trans-SNARE complex for yeast vacuole fusion- Starai VJ, Hickey CM, Wickner W Department of Biochemistry, Dartmouth Medical School, Hanover, NH 03755, USA- Abstract: The fusion of yeast vacuoles, like other organelles, requires a Rab-family guanosine triphosphatase -Ypt7p-, a Rab effector and Sec1-Munc18 -SM- complex termed HOPS -homotypic fusion and vacuole protein sorting-, and soluble N-ethylmaleimide-sensitive factor attachment protein receptors -SNAREs-- The central 0-layer of the four bundled vacuolar SNAREs requires the wild-type three glutaminyl -Q- and one arginyl -R- residues for optimal fusion- Alterations of this layer dramatically increase the K-m- value for SNAREs to assemble trans-SNARE complexes and to fuse- We now find that added purified HOPS complex strongly suppresses the fusion of vacuoles bearing 0-layer alterations, but it has little effect on the fusion of vacuoles with wild-type SNAREs- HOPS proofreads at two levels, inhibiting the formation of trans-SNARE complexes with altered 0-layers and suppressing the ability of these mismatched 0-layer trans-SNARE complexes to support membrane fusion- HOPS proofreading also extends to other parts of the SNARE complex, because it suppresses the fusion of trans-SNARE complexes formed without the N-terminal Phox homology domain of Vam7p -Q-c--- Unlike some other SM proteins, HOPS proofreading does not require the Vam3p -Q-a-- N-terminal domain- HOPS thus proofreads SNARE domain and N-terminal domain structures and regulates the fusion capacity of trans-SNARE complexes, only allowing full function for wild-type SNARE configurations- This is the most direct evidence to date that HOPS is directly involved in the fusion event- [PUBMED: 18385512] Copyright © 2009, Tyers Lab, The Samuel Lunenfeld Research Institute, Mount Sinai Hospital, All Rights Reserved. terms and conditions - privacy policy - Osprey Network Visualization System BioGRID: A General Repository for Interaction Datasets. Chris Stark, Bobby-Joe Breitkreutz, Teresa Reguly, Lorrie Boucher, Ashton Breitkreutz, Mike Tyers. Nucleic Acids Res. Jan 1;34:D535-9.