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Remodeling of actin filaments by ADF/cofilin proteins.

ABSTRACT: Cofilin/ADF proteins play key roles in the dynamics of actin, one of the most abundant and highly conserved eukaryotic proteins. We used cryoelectron microscopy to generate a 9-Å resolution three-dimensional reconstruction of cofilin-decorated actin filaments, the highest resolution achieved for a complex of F-actin with an actin-binding protein. We show that the cofilin-induced change in the filament twist is due to a unique conformation of the actin molecule unrelated to any previously observed state. The changes between the actin protomer in naked F-actin and in the actin-cofilin filament are greater than the conformational changes between G- and F-actin. Our results show the structural plasticity of actin, suggest that other actin-binding proteins may also induce large but different conformational changes, and show that F-actin cannot be described by a single molecular model.

SUBMITTER: Galkin VE

PROVIDER: S-EPMC3251117 | biostudies-literature | 2011 Dec

REPOSITORIES: biostudies-literature

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Remodeling of actin filaments by ADF/cofilin proteins.

Galkin Vitold E VE Orlova Albina A Kudryashov Dmitri S DS Solodukhin Alexander A Reisler Emil E Schröder Gunnar F GF Egelman Edward H EH

Proceedings of the National Academy of Sciences of the United States of America 20111207 51

Cofilin/ADF proteins play key roles in the dynamics of actin, one of the most abundant and highly conserved eukaryotic proteins. We used cryoelectron microscopy to generate a 9-Å resolution three-dimensional reconstruction of cofilin-decorated actin filaments, the highest resolution achieved for a complex of F-actin with an actin-binding protein. We show that the cofilin-induced change in the filament twist is due to a unique conformation of the actin molecule unrelated to any previously observe ...[more]

PMID: 22158895

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