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Role of curvature and phase transition in lipid sorting and fission of membrane tubules.

ABSTRACT: We have recently developed a minimal system for generating long tubular nanostructures that resemble tubes observed in vivo with biological membranes. Here, we studied membrane tube pulling in ternary mixtures of sphingomyelin, phosphatidylcholine and cholesterol. Two salient results emerged: the lipid composition is significantly different in the tubes and in the vesicles; tube fission is observed when phase separation is generated in the tubes. This shows that lipid sorting may depend critically on both membrane curvature and phase separation. Phase separation also appears to be important for membrane fission in tubes pulled out of giant liposomes or purified Golgi membranes.

SUBMITTER: Roux A

PROVIDER: S-EPMC1142567 | biostudies-literature | 2005 Apr

REPOSITORIES: biostudies-literature

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Role of curvature and phase transition in lipid sorting and fission of membrane tubules.

Roux Aurélien A Cuvelier Damien D Nassoy Pierre P Prost Jacques J Bassereau Patricia P Goud Bruno B

The EMBO journal 20050324 8

We have recently developed a minimal system for generating long tubular nanostructures that resemble tubes observed in vivo with biological membranes. Here, we studied membrane tube pulling in ternary mixtures of sphingomyelin, phosphatidylcholine and cholesterol. Two salient results emerged: the lipid composition is significantly different in the tubes and in the vesicles; tube fission is observed when phase separation is generated in the tubes. This shows that lipid sorting may depend critical ...[more]

PMID: 15791208

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