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Cytokinesis requires localized ?-actin filament production by an actin isoform specific nucleator.

ABSTRACT: Cytokinesis is initiated by the localized assembly of the contractile ring, a dynamic actomyosin structure that generates a membrane furrow between the segregating chromosomal masses to divide a cell into two. Here we show that the stabilization and organization of the cytokinetic furrow is specifically dependent on localized ?-actin filament assembly at the site of cytokinesis. ?-actin filaments are assembled directly at the furrow by an anillin-dependent pathway that enhances RhoA-dependent activation of the formin DIAPH3, an actin nucleator. DIAPH3 specifically generates homopolymeric filaments of ?-actin in vitro. By employing enhancers and activators, cells can achieve acute spatio-temporal control over isoform-specific actin arrays that are required for distinct cellular functions.

SUBMITTER: Chen A

PROVIDER: S-EPMC5691081 | biostudies-other | 2017 Nov

REPOSITORIES: biostudies-other

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Cytokinesis requires localized β-actin filament production by an actin isoform specific nucleator.

Chen A A Arora P D PD McCulloch C A CA Wilde A A

Nature communications 20171116 1

Cytokinesis is initiated by the localized assembly of the contractile ring, a dynamic actomyosin structure that generates a membrane furrow between the segregating chromosomal masses to divide a cell into two. Here we show that the stabilization and organization of the cytokinetic furrow is specifically dependent on localized β-actin filament assembly at the site of cytokinesis. β-actin filaments are assembled directly at the furrow by an anillin-dependent pathway that enhances RhoA-dependent ac ...[more]

PMID: 29146911

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