Mechanism of actin filament branch formation by Arp2/3 complex revealed by a high-resolution cryo-EM structure of the branch junction

22Citations
Citations of this article
15Readers
Mendeley users who have this article in their library.
Get full text

Abstract

We reconstructed the structure of actin filament branch junctions formed by fission yeast Arp2/3 complex at 3.5 Å resolution from images collected by electron cryomicroscopy. During specimen preparation, all of the actin subunits and Arp3 hydrolyzed their bound adenosine triphosphate (ATP) and dissociated the γ-phosphate, but Arp2 retained the γ-phosphate. Binding tightly to the side of the mother filament and nucleating the daughter filament growing as a branch requires Arp2/3 complex to undergo a dramatic conformational change where two blocks of structure rotate relative to each other about 25° to align Arp2 and Arp3 as the first two subunits in the branch. During branch formation, Arp2/3 complex acquires more than 8,000 Å2 of new buried surface, accounting for the stability of the branch. Inactive Arp2/3 complex binds only transiently to the side of an actin filament, because its conformation allows only a subset of the interactions found in the branch junction.

Cite

CITATION STYLE

APA

Chou, S. Z., Chatterjee, M., & Pollard, T. D. (2022). Mechanism of actin filament branch formation by Arp2/3 complex revealed by a high-resolution cryo-EM structure of the branch junction. Proceedings of the National Academy of Sciences of the United States of America, 119(49). https://doi.org/10.1073/pnas.2206722119

Register to see more suggestions

Mendeley helps you to discover research relevant for your work.

Already have an account?

Save time finding and organizing research with Mendeley

Sign up for free