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α-Synuclein Reduces Tension and Increases Undulations in Simulations of Small Unilamellar Vesicles.

ABSTRACT: Using coarse-grained molecular dynamics simulations we have explored the effect of α-Synuclein (αSyn) on the structural and mechanical properties of small unilamellar vesicles in the fluid-phase. The study is motivated by observations that a high density of membrane-bound αSyn inhibits the fusion of synthetic small unilamellar vesicles. By combining three-dimensional pressure tensor calculations with our recently developed spherical harmonics fluctuation analysis approach, we show a reduction in membrane surface tension and increased membrane undulations when αSyn is bound to the vesicle's outer leaflet at a 200:1 L/P. The protein effects these changes by decreasing the negative pressure in the headgroup region of the outer leaflet and increasing the positive pressure throughout the hydrocarbon core.

SUBMITTER: Braun AR

PROVIDER: S-EPMC4407265 | biostudies-literature | 2015 Apr

REPOSITORIES: biostudies-literature

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α-Synuclein Reduces Tension and Increases Undulations in Simulations of Small Unilamellar Vesicles.

Braun Anthony R AR Sachs Jonathan N JN

Biophysical journal 20150401 8

Using coarse-grained molecular dynamics simulations we have explored the effect of α-Synuclein (αSyn) on the structural and mechanical properties of small unilamellar vesicles in the fluid-phase. The study is motivated by observations that a high density of membrane-bound αSyn inhibits the fusion of synthetic small unilamellar vesicles. By combining three-dimensional pressure tensor calculations with our recently developed spherical harmonics fluctuation analysis approach, we show a reduction in ...[more]

PMID: 25902424

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