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The tethering complex HOPS catalyzes assembly of the soluble SNARE Vam7 into fusogenic trans-SNARE complexes

The fusion of yeast vacuolar membranes depends on the disassembly of cis–soluble N-ethylmaleimide–sensitive factor attachment protein receptor (SNARE) complexes and the subsequent reassembly of new SNARE complexes in trans. The disassembly of cis-SNARE complexes by Sec17/Sec18p releases the soluble...

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Autores principales: Zick, Michael, Wickner, William
Formato: Online Artículo Texto
Lenguaje:English
Publicado: The American Society for Cell Biology 2013
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3843000/
https://www.ncbi.nlm.nih.gov/pubmed/24088569
http://dx.doi.org/10.1091/mbc.E13-07-0419
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author Zick, Michael
Wickner, William
author_facet Zick, Michael
Wickner, William
author_sort Zick, Michael
collection PubMed
description The fusion of yeast vacuolar membranes depends on the disassembly of cis–soluble N-ethylmaleimide–sensitive factor attachment protein receptor (SNARE) complexes and the subsequent reassembly of new SNARE complexes in trans. The disassembly of cis-SNARE complexes by Sec17/Sec18p releases the soluble SNARE Vam7p from vacuolar membranes. Consequently, Vam7p needs to be recruited to the membrane at future sites of fusion to allow the formation of trans-SNARE complexes. The multisubunit tethering homotypic fusion and vacuole protein sorting (HOPS) complex, which is essential for the fusion of vacuolar membranes, was previously shown to have direct affinity for Vam7p. The functional significance of this interaction, however, has been unclear. Using a fully reconstituted in vitro fusion reaction, we now show that HOPS facilitates membrane fusion by recruiting Vam7p for fusion. In the presence of HOPS, unlike with other tethering agents, very low levels of added Vam7p suffice to induce vigorous fusion. This is a specific recruitment of Vam7p rather than an indirect stimulation of SNARE complex formation through tethering, as HOPS does not facilitate fusion with a low amount of a soluble form of another vacuolar SNARE, Vti1p. Our findings establish yet another function among the multiple tasks that HOPS performs to catalyze the fusion of yeast vacuoles.
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spelling pubmed-38430002014-02-16 The tethering complex HOPS catalyzes assembly of the soluble SNARE Vam7 into fusogenic trans-SNARE complexes Zick, Michael Wickner, William Mol Biol Cell Articles The fusion of yeast vacuolar membranes depends on the disassembly of cis–soluble N-ethylmaleimide–sensitive factor attachment protein receptor (SNARE) complexes and the subsequent reassembly of new SNARE complexes in trans. The disassembly of cis-SNARE complexes by Sec17/Sec18p releases the soluble SNARE Vam7p from vacuolar membranes. Consequently, Vam7p needs to be recruited to the membrane at future sites of fusion to allow the formation of trans-SNARE complexes. The multisubunit tethering homotypic fusion and vacuole protein sorting (HOPS) complex, which is essential for the fusion of vacuolar membranes, was previously shown to have direct affinity for Vam7p. The functional significance of this interaction, however, has been unclear. Using a fully reconstituted in vitro fusion reaction, we now show that HOPS facilitates membrane fusion by recruiting Vam7p for fusion. In the presence of HOPS, unlike with other tethering agents, very low levels of added Vam7p suffice to induce vigorous fusion. This is a specific recruitment of Vam7p rather than an indirect stimulation of SNARE complex formation through tethering, as HOPS does not facilitate fusion with a low amount of a soluble form of another vacuolar SNARE, Vti1p. Our findings establish yet another function among the multiple tasks that HOPS performs to catalyze the fusion of yeast vacuoles. The American Society for Cell Biology 2013-12-01 /pmc/articles/PMC3843000/ /pubmed/24088569 http://dx.doi.org/10.1091/mbc.E13-07-0419 Text en © 2013 Zick and Wickner. This article is distributed by The American Society for Cell Biology under license from the author(s). Two months after publication it is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0). “ASCB®,” “The American Society for Cell Biology®,” and “Molecular Biology of the Cell®” are registered trademarks of The American Society of Cell Biology.
spellingShingle Articles
Zick, Michael
Wickner, William
The tethering complex HOPS catalyzes assembly of the soluble SNARE Vam7 into fusogenic trans-SNARE complexes
title The tethering complex HOPS catalyzes assembly of the soluble SNARE Vam7 into fusogenic trans-SNARE complexes
title_full The tethering complex HOPS catalyzes assembly of the soluble SNARE Vam7 into fusogenic trans-SNARE complexes
title_fullStr The tethering complex HOPS catalyzes assembly of the soluble SNARE Vam7 into fusogenic trans-SNARE complexes
title_full_unstemmed The tethering complex HOPS catalyzes assembly of the soluble SNARE Vam7 into fusogenic trans-SNARE complexes
title_short The tethering complex HOPS catalyzes assembly of the soluble SNARE Vam7 into fusogenic trans-SNARE complexes
title_sort tethering complex hops catalyzes assembly of the soluble snare vam7 into fusogenic trans-snare complexes
topic Articles
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3843000/
https://www.ncbi.nlm.nih.gov/pubmed/24088569
http://dx.doi.org/10.1091/mbc.E13-07-0419
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