Remodeling of actin filaments by ADF/cofilin proteins

Proc Natl Acad Sci U S A. 2011 Dec 20;108(51):20568-72. doi: 10.1073/pnas.1110109108. Epub 2011 Dec 7.


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.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Actin Depolymerizing Factors / chemistry*
  • Actins / chemistry*
  • Cofilin 2 / chemistry*
  • Cryoelectron Microscopy / methods
  • Cytoskeleton / chemistry*
  • Gene Library
  • Humans
  • Microscopy, Electron / methods
  • Models, Molecular
  • Molecular Conformation
  • Muscle, Skeletal / metabolism
  • Polymers / chemistry*
  • Protein Conformation
  • Protein Structure, Secondary


  • Actin Depolymerizing Factors
  • Actins
  • Cofilin 2
  • Polymers

Associated data

  • PDB/3J0S