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Vesicle fusion observed by content transfer across a tethered lipid bilayer.

ABSTRACT: Synaptic transmission is achieved by exocytosis of small, synaptic vesicles containing neurotransmitters across the plasma membrane. Here, we use a DNA-tethered freestanding bilayer as a target architecture that allows observation of content transfer of individual vesicles across the tethered planar bilayer. Tethering and fusion are mediated by hybridization of complementary DNA-lipid conjugates inserted into the two membranes, and content transfer is monitored by the dequenching of an aqueous content dye. By analyzing the diffusion profile of the aqueous dye after vesicle fusion, we are able to distinguish content transfer across the tethered bilayer patch from vesicle leakage above the patch.

SUBMITTER: Rawle RJ

PROVIDER: S-EPMC3192961 | biostudies-literature | 2011 Oct

REPOSITORIES: biostudies-literature

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Vesicle fusion observed by content transfer across a tethered lipid bilayer.

Rawle Robert J RJ van Lengerich Bettina B Chung Minsub M Bendix Poul Martin PM Boxer Steven G SG

Biophysical journal 20111001 8

Synaptic transmission is achieved by exocytosis of small, synaptic vesicles containing neurotransmitters across the plasma membrane. Here, we use a DNA-tethered freestanding bilayer as a target architecture that allows observation of content transfer of individual vesicles across the tethered planar bilayer. Tethering and fusion are mediated by hybridization of complementary DNA-lipid conjugates inserted into the two membranes, and content transfer is monitored by the dequenching of an aqueous c ...[more]

PMID: 22004762

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