NPF binding to Arp2 is allosterically linked to the release of ArpC5's N-terminal tail and conformational changes in Arp2/3 complex.

ABSTRACT: Arp2/3 complex generates branched actin networks essential for numerous motile functions of the cell. It comprises seven subunits: actin-related proteins (Arps) 2 and 3 and five scaffolding subunits (ArpC1-5). The complex adopts two major conformations: inactive, with the Arps interacting end-to-end, and active, with the Arps aligned side-by-side like subunits in the actin filament. Activation involves several cofactors, including ATP, WASP-family nucleation-promoting factors (NPFs), actin monomers, and the mother actin filament. NPFs bind to two sites, one on Arp2-ArpC1 and one on Arp3, delivering actin subunits at the barbed end of the Arps to initiate branch elongation. However, the mechanisms by which each NPF drives the equilibrium toward activation remain unclear. We present two cryo

SUBMITTER: Saks AJ 

PROVIDER: S-EPMC11873952 | biostudies-literature | 2025 Feb

REPOSITORIES: biostudies-literature