HOPS prevents the disassembly of trans-SNARE complexes by Sec17p/Sec18p during membrane fusion
Open Access
- 14 May 2010
- journal article
- research article
- Published by Springer Science and Business Media LLC in The EMBO Journal
- Vol. 29 (12), 1948-1960
- https://doi.org/10.1038/emboj.2010.97
Abstract
SNARE‐dependent membrane fusion requires the disassembly of cis ‐SNARE complexes (formed by SNAREs anchored to one membrane) followed by the assembly of trans ‐SNARE complexes (SNAREs anchored to two apposed membranes). Although SNARE complex disassembly and assembly might be thought to be opposing reactions, the proteins promoting disassembly (Sec17p/Sec18p) and assembly (the HOPS complex) work synergistically to support fusion. We now report that trans ‐SNARE complexes formed during vacuole fusion are largely associated with Sec17p. Using a reconstituted proteoliposome fusion system, we show that trans ‐SNARE complex, like cis ‐SNARE complex, is sensitive to Sec17p/Sec18p mediated disassembly. Strikingly, HOPS inhibits the disassembly of SNARE complexes in the trans ‐, but not in the cis ‐, configuration. This selective HOPS preservation of trans ‐SNARE complexes requires HOPS:SNARE recognition and is lost when the apposed bilayers are dissolved in Triton X‐100; it is also observed during fusion of isolated vacuoles. HOPS thus directs the Sec17p/Sec18p chaperone system to maximize functional trans ‐SNARE complex for membrane fusion, a new role of tethering factors during membrane traffic.Keywords
This publication has 66 references indexed in Scilit:
- Minimal membrane docking requirements revealed by reconstitution of Rab GTPase-dependent membrane fusion from purified componentsProceedings of the National Academy of Sciences, 2009
- Direct interaction between the COG complex and the SM protein, Sly1, is required for Golgi SNARE pairingThe EMBO Journal, 2009
- Reconstituted membrane fusion requires regulatory lipids, SNAREs and synergistic SNARE chaperonesThe EMBO Journal, 2008
- Membrane fusionNature Structural & Molecular Biology, 2008
- Sec18p and Vam7p remodel trans-SNARE complexes to permit a lipid-anchored R-SNARE to support yeast vacuole fusionThe EMBO Journal, 2007
- Excess vacuolar SNAREs drive lysis and Rab bypass fusionProceedings of the National Academy of Sciences of the United States of America, 2007
- trans-SNARE complex assembly and yeast vacuole membrane fusionProceedings of the National Academy of Sciences, 2007
- Rabs and their effectors: Achieving specificity in membrane trafficProceedings of the National Academy of Sciences, 2006
- Purification of active HOPS complex reveals its affinities for phosphoinositides and the SNARE Vam7pThe EMBO Journal, 2006
- An approach to correlate tandem mass spectral data of peptides with amino acid sequences in a protein databaseJournal of the American Society for Mass Spectrometry, 1994