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Nucleation, stabilization, and disassembly of branched actin networks.

ABSTRACT: Arp2/3 complex is an actin filament nucleation and branching machinery conserved in all eukaryotes from yeast to human. Arp2/3 complex branched networks generate pushing forces that drive cellular processes ranging from membrane remodeling to cell and organelle motility. Several molecules regulate these processes by directly inhibiting or activating Arp2/3 complex and by stabilizing or disassembling branched networks. Here, we review recent advances in our understanding of Arp2/3 complex regulation, including high-resolution cryoelectron microscopy (cryo-EM) structures that illuminate the mechanisms of Arp2/3 complex activation and branch formation, and novel cellular pathways of branch formation, stabilization, and debranching. We also identify major gaps in our understanding of Arp2/3 complex inhibition and branch stabilization and disassembly.

SUBMITTER: Gautreau AM

PROVIDER: S-EPMC9018471 | biostudies-literature | 2022 May

REPOSITORIES: biostudies-literature

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Nucleation, stabilization, and disassembly of branched actin networks.

Gautreau Alexis M AM Fregoso Fred E FE Simanov Gleb G Dominguez Roberto R

Trends in cell biology 20211123 5

Arp2/3 complex is an actin filament nucleation and branching machinery conserved in all eukaryotes from yeast to human. Arp2/3 complex branched networks generate pushing forces that drive cellular processes ranging from membrane remodeling to cell and organelle motility. Several molecules regulate these processes by directly inhibiting or activating Arp2/3 complex and by stabilizing or disassembling branched networks. Here, we review recent advances in our understanding of Arp2/3 complex regulat ...[more]

PMID: 34836783

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