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T-SNARE Transmembrane Domain Clustering Modulates Lipid Organization and Membrane Curvature.

ABSTRACT: The t-SNARE complex plays a central role in neuronal fusion. Its components, syntaxin-1 and SNAP25, are largely present in individual clusters and partially colocalize at the presumptive fusion site. How these protein clusters modify local lipid composition and membrane morphology is largely unknown. In this work, using coarse-grained molecular dynamics, the transmembrane domains (TMDs) of t-SNARE complexes are shown to form aggregates leading to formation of lipid nanodomains, which are enriched in cholesterol, phosphatidylinositol 4,5-bisphosphate, and gangliosidic lipids. These nano-domains induce membrane curvature that would promote a closer contact between vesicle and plasma membrane.

SUBMITTER: Sharma S

PROVIDER: S-EPMC5802331 | biostudies-literature | 2017 Dec

REPOSITORIES: biostudies-literature

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t-SNARE Transmembrane Domain Clustering Modulates Lipid Organization and Membrane Curvature.

Sharma Satyan S Lindau Manfred M

Journal of the American Chemical Society 20171213 51

The t-SNARE complex plays a central role in neuronal fusion. Its components, syntaxin-1 and SNAP25, are largely present in individual clusters and partially colocalize at the presumptive fusion site. How these protein clusters modify local lipid composition and membrane morphology is largely unknown. In this work, using coarse-grained molecular dynamics, the transmembrane domains (TMDs) of t-SNARE complexes are shown to form aggregates leading to formation of lipid nanodomains, which are enriche ...[more]

PMID: 29231734

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