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Inhibition of Cdc42 during mitotic exit is required for cytokinesis.

ABSTRACT: The role of Cdc42 and its regulation during cytokinesis is not well understood. Using biochemical and imaging approaches in budding yeast, we demonstrate that Cdc42 activation peaks during the G1/S transition and during anaphase but drops during mitotic exit and cytokinesis. Cdc5/Polo kinase is an important upstream cell cycle regulator that suppresses Cdc42 activity. Failure to down-regulate Cdc42 during mitotic exit impairs the normal localization of key cytokinesis regulators-Iqg1 and Inn1-at the division site, and results in an abnormal septum. The effects of Cdc42 hyperactivation are largely mediated by the Cdc42 effector p21-activated kinase Ste20. Inhibition of Cdc42 and related Rho guanosine triphosphatases may be a general feature of cytokinesis in eukaryotes.

SUBMITTER: Atkins BD

PROVIDER: S-EPMC3718968 | biostudies-literature | 2013 Jul

REPOSITORIES: biostudies-literature

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Inhibition of Cdc42 during mitotic exit is required for cytokinesis.

Atkins Benjamin D BD Yoshida Satoshi S Saito Koji K Wu Chi-Fang CF Lew Daniel J DJ Pellman David D

The Journal of cell biology 20130701 2

The role of Cdc42 and its regulation during cytokinesis is not well understood. Using biochemical and imaging approaches in budding yeast, we demonstrate that Cdc42 activation peaks during the G1/S transition and during anaphase but drops during mitotic exit and cytokinesis. Cdc5/Polo kinase is an important upstream cell cycle regulator that suppresses Cdc42 activity. Failure to down-regulate Cdc42 during mitotic exit impairs the normal localization of key cytokinesis regulators-Iqg1 and Inn1-at ...[more]

PMID: 23878274

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