Molecular basis for the dual function of Eps8 on actin dynamics: bundling and capping.

ABSTRACT: Actin capping and cross-linking proteins regulate the dynamics and architectures of different cellular protrusions. Eps8 is the founding member of a unique family of capping proteins capable of side-binding and bundling actin filaments. However, the structural basis through which Eps8 exerts these functions remains elusive. Here, we combined biochemical, molecular, and genetic approaches with electron microscopy and image analysis to dissect the molecular mechanism responsible for the distinct activities of Eps8. We propose that bundling activity of Eps8 is mainly mediated by a compact four helix bundle, which is contacting three actin subunits along the filament. The capping activity is mainly mediated by a amphipathic helix that binds within the hydrophobic pocket at the barbed ends of a

SUBMITTER: Hertzog M 

PROVIDER: S-EPMC2879411 | biostudies-literature | 2010 Jun

REPOSITORIES: biostudies-literature