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Cell-intrinsic and -extrinsic mechanisms promote cell-type-specific cytokinetic diversity.

ABSTRACT: Cytokinesis, the physical division of one cell into two, is powered by constriction of an actomyosin contractile ring. It has long been assumed that all animal cells divide by a similar molecular mechanism, but growing evidence suggests that cytokinetic regulation in individual cell types has more variation than previously realized. In the four-cell Caenorhabditis elegans embryo, each blastomere has a distinct cell fate, specified by conserved pathways. Using fast-acting temperature-sensitive mutants and acute drug treatment, we identified cell-type-specific variation in the cytokinetic requirement for a robust formin^CYK-1-dependent filamentous-actin (F-actin) cytoskeleton. In one cell (P2), this cytokinetic variation is cell-intrinsically regulated, whereas in another cell (EMS) this variation is cell-extrinsically regulated, dependent on both Src^SRC-1 signaling and direct contact with its neighbor cell, P2. Thus, both cell-intrinsic and -extrinsic mechanisms control cytokinetic variation in individual cell types and can protect against division failure when the contractile ring is weakened.

SUBMITTER: Davies T

PROVIDER: S-EPMC6054530 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature

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Cell-intrinsic and -extrinsic mechanisms promote cell-type-specific cytokinetic diversity.

Davies Tim T Kim Han X HX Romano Spica Natalia N Lesea-Pringle Benjamin J BJ Dumont Julien J Shirasu-Hiza Mimi M Canman Julie C JC

eLife 20180720

Cytokinesis, the physical division of one cell into two, is powered by constriction of an actomyosin contractile ring. It has long been assumed that all animal cells divide by a similar molecular mechanism, but growing evidence suggests that cytokinetic regulation in individual cell types has more variation than previously realized. In the four-cell <i>Caenorhabditis elegans</i> embryo, each blastomere has a distinct cell fate, specified by conserved pathways. Using fast-acting temperature-sensi ...[more]

PMID: 30028292

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Cell-intrinsic and -extrinsic mechanisms promote cell-type-specific cytokinetic diversity.

Publications

Cell-intrinsic and -extrinsic mechanisms promote cell-type-specific cytokinetic diversity.

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