Direct observation of the conformational states of formin mDia1 at actin filament barbed ends and along the filament.

ABSTRACT: The fine regulation of actin polymerization is essential to control cell motility and architecture and to perform essential cellular functions. Formins are key regulators of actin filament assembly, known to processively elongate filament barbed ends and increase their polymerization rate. Different models have been extrapolated to describe the molecular mechanism governing the processive motion of formin FH2 domains at polymerizing barbed ends. Using negative stain electron microscopy, we directly identified for the first time two conformations of the mDia1 formin FH2 domains in interaction with the barbed ends of actin filaments. These conformations agree with the speculated open and closed conformations of the "stair-stepping" model. We observed the FH2 dimers to be in the open conforma

SUBMITTER: Maufront J 

PROVIDER: S-EPMC9816646 | biostudies-literature | 2023 Jan

REPOSITORIES: biostudies-literature