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High-resolution temporal analysis reveals a functional timeline for the molecular regulation of cytokinesis.

ABSTRACT: To take full advantage of fast-acting temperature-sensitive mutations, thermal control must be extremely rapid. We developed the Therminator, a device capable of shifting sample temperature in ~17 s while simultaneously imaging cell division in vivo. Applying this technology to six key regulators of cytokinesis, we found that each has a distinct temporal requirement in the Caenorhabditis elegans zygote. Specifically, myosin-II is required throughout cytokinesis until contractile ring closure. In contrast, formin-mediated actin nucleation is only required during assembly and early contractile ring constriction. Centralspindlin is required to maintain division after ring closure, although its GAP activity is only required until just prior to closure. Finally, the chromosomal passenger complex is required for cytokinesis only early in mitosis, but not during metaphase or cytokinesis. Together, our results provide a precise functional timeline for molecular regulators of cytokinesis using the Therminator, a powerful tool for ultra-rapid protein inactivation.

SUBMITTER: Davies T

PROVIDER: S-EPMC4245203 | biostudies-literature | 2014 Jul

REPOSITORIES: biostudies-literature

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High-resolution temporal analysis reveals a functional timeline for the molecular regulation of cytokinesis.

Davies Tim T Jordan Shawn N SN Chand Vandana V Sees Jennifer A JA Laband Kimberley K Carvalho Ana X AX Shirasu-Hiza Mimi M Kovar David R DR Dumont Julien J Canman Julie C JC

Developmental cell 20140701 2

To take full advantage of fast-acting temperature-sensitive mutations, thermal control must be extremely rapid. We developed the Therminator, a device capable of shifting sample temperature in ~17 s while simultaneously imaging cell division in vivo. Applying this technology to six key regulators of cytokinesis, we found that each has a distinct temporal requirement in the Caenorhabditis elegans zygote. Specifically, myosin-II is required throughout cytokinesis until contractile ring closure. In ...[more]

PMID: 25073157

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High-resolution temporal analysis reveals a functional timeline for the molecular regulation of cytokinesis.

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High-resolution temporal analysis reveals a functional timeline for the molecular regulation of cytokinesis.

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