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Membrane curvature induced by Arf1-GTP is essential for vesicle formation.

ABSTRACT: The GTPase Arf1 is considered as a molecular switch that regulates binding and release of coat proteins that polymerize on membranes to form transport vesicles. Here, we show that Arf1-GTP induces positive membrane curvature and find that the small GTPase can dimerize dependent on GTP. Investigating a possible link between Arf dimerization and curvature formation, we isolated an Arf1 mutant that cannot dimerize. Although it was capable of exerting the classical role of Arf1 as a coat receptor, it could not mediate the formation of COPI vesicles from Golgi-membranes and was lethal when expressed in yeast. Strikingly, this mutant was not able to deform membranes, suggesting that GTP-induced dimerization of Arf1 is a critical step inducing membrane curvature during the formation of coated vesicles.

SUBMITTER: Beck R

PROVIDER: S-EPMC2575275 | biostudies-literature | 2008 Aug

REPOSITORIES: biostudies-literature

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Membrane curvature induced by Arf1-GTP is essential for vesicle formation.

Beck Rainer R Sun Zhe Z Adolf Frank F Rutz Chistoph C Bassler Jochen J Wild Klemens K Sinning Irmgard I Hurt Ed E Brügger Britta B Béthune Julien J Wieland Felix F

Proceedings of the National Academy of Sciences of the United States of America 20080808 33

The GTPase Arf1 is considered as a molecular switch that regulates binding and release of coat proteins that polymerize on membranes to form transport vesicles. Here, we show that Arf1-GTP induces positive membrane curvature and find that the small GTPase can dimerize dependent on GTP. Investigating a possible link between Arf dimerization and curvature formation, we isolated an Arf1 mutant that cannot dimerize. Although it was capable of exerting the classical role of Arf1 as a coat receptor, i ...[more]

PMID: 18689681

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Dataset Information

Membrane curvature induced by Arf1-GTP is essential for vesicle formation.

Publications

Membrane curvature induced by Arf1-GTP is essential for vesicle formation.

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