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Topological arrangement of the intracellular membrane fusion machinery
Soluble N-ethylmaleimide–sensitive factor attachment protein receptors (SNAREs) form a four-helix coiled-coil bundle that juxtaposes two bilayers and drives a basal level of membrane fusion. The Sec1/Munc18 (SM) protein binds to its cognate SNARE bundle and accelerates the basal fusion reaction. The...
Autores principales: | , , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
The American Society for Cell Biology
2011
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3135485/ https://www.ncbi.nlm.nih.gov/pubmed/21633111 http://dx.doi.org/10.1091/mbc.E11-03-0190 |
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author | Rathore, Shailendra S. Ghosh, Nilanjan Ouyang, Yan Shen, Jingshi |
author_facet | Rathore, Shailendra S. Ghosh, Nilanjan Ouyang, Yan Shen, Jingshi |
author_sort | Rathore, Shailendra S. |
collection | PubMed |
description | Soluble N-ethylmaleimide–sensitive factor attachment protein receptors (SNAREs) form a four-helix coiled-coil bundle that juxtaposes two bilayers and drives a basal level of membrane fusion. The Sec1/Munc18 (SM) protein binds to its cognate SNARE bundle and accelerates the basal fusion reaction. The question of how the topological arrangement of the SNARE helices affects the reactivity of the fusion proteins remains unanswered. Here we address the problem for the first time in a reconstituted system containing both SNAREs and SM proteins. We find that to be fusogenic a SNARE topology must support both basal fusion and SM stimulation. Certain topological combinations of exocytic SNAREs result in basal fusion but cannot support SM stimulation, whereas other topologies support SM stimulation without inducing basal fusion. It is striking that of all the possible topological combinations of exocytic SNARE helices, only one induces efficient fusion. Our results suggest that the intracellular membrane fusion complex is designed to fuse bilayers according to one genetically programmed topology. |
format | Online Article Text |
id | pubmed-3135485 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2011 |
publisher | The American Society for Cell Biology |
record_format | MEDLINE/PubMed |
spelling | pubmed-31354852011-09-30 Topological arrangement of the intracellular membrane fusion machinery Rathore, Shailendra S. Ghosh, Nilanjan Ouyang, Yan Shen, Jingshi Mol Biol Cell Articles Soluble N-ethylmaleimide–sensitive factor attachment protein receptors (SNAREs) form a four-helix coiled-coil bundle that juxtaposes two bilayers and drives a basal level of membrane fusion. The Sec1/Munc18 (SM) protein binds to its cognate SNARE bundle and accelerates the basal fusion reaction. The question of how the topological arrangement of the SNARE helices affects the reactivity of the fusion proteins remains unanswered. Here we address the problem for the first time in a reconstituted system containing both SNAREs and SM proteins. We find that to be fusogenic a SNARE topology must support both basal fusion and SM stimulation. Certain topological combinations of exocytic SNAREs result in basal fusion but cannot support SM stimulation, whereas other topologies support SM stimulation without inducing basal fusion. It is striking that of all the possible topological combinations of exocytic SNARE helices, only one induces efficient fusion. Our results suggest that the intracellular membrane fusion complex is designed to fuse bilayers according to one genetically programmed topology. The American Society for Cell Biology 2011-07-15 /pmc/articles/PMC3135485/ /pubmed/21633111 http://dx.doi.org/10.1091/mbc.E11-03-0190 Text en © 2011 Rathore et al. 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 Rathore, Shailendra S. Ghosh, Nilanjan Ouyang, Yan Shen, Jingshi Topological arrangement of the intracellular membrane fusion machinery |
title | Topological arrangement of the intracellular membrane fusion machinery |
title_full | Topological arrangement of the intracellular membrane fusion machinery |
title_fullStr | Topological arrangement of the intracellular membrane fusion machinery |
title_full_unstemmed | Topological arrangement of the intracellular membrane fusion machinery |
title_short | Topological arrangement of the intracellular membrane fusion machinery |
title_sort | topological arrangement of the intracellular membrane fusion machinery |
topic | Articles |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3135485/ https://www.ncbi.nlm.nih.gov/pubmed/21633111 http://dx.doi.org/10.1091/mbc.E11-03-0190 |
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