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Cytokinesis is not controlled by calmodulin or myosin light chain kinase in the Caenorhabditis elegans early embryo.

ABSTRACT: Furrow ingression in animal cell cytokinesis is controlled by phosphorylation of myosin II regulatory light chain (mRLC). In Caenorhabditis elegans embryos, Rho-dependent Kinase (RhoK) is involved in, but not absolutely required for, this phosphorylation. The calmodulin effector myosin light chain kinase (MLCK) can also phosphorylate mRLC and is widely regarded as a candidate for redundant function with RhoK. However, our results show that RNA mediated interference against C. elegans calmodulin and candidate MLCKs had no effect on cytokinesis in wild-type or RhoK mutant embryos, ruling out the calmodulin/MLCK pathway as the missing regulator of cytokinesis in the C. elegans early embryo.

SUBMITTER: Batchelder EL

PROVIDER: S-EPMC2144740 | biostudies-literature | 2007 Sep

REPOSITORIES: biostudies-literature

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Cytokinesis is not controlled by calmodulin or myosin light chain kinase in the Caenorhabditis elegans early embryo.

Batchelder Ellen L EL Thomas-Virnig Christina L CL Hardin Jeffery D JD White John G JG

FEBS letters 20070814 22

Furrow ingression in animal cell cytokinesis is controlled by phosphorylation of myosin II regulatory light chain (mRLC). In Caenorhabditis elegans embryos, Rho-dependent Kinase (RhoK) is involved in, but not absolutely required for, this phosphorylation. The calmodulin effector myosin light chain kinase (MLCK) can also phosphorylate mRLC and is widely regarded as a candidate for redundant function with RhoK. However, our results show that RNA mediated interference against C. elegans calmodulin ...[more]

PMID: 17716666

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