Mitotic Exit Control: A Space and Time Odyssey

Department of Genetics, University of Cambridge, Cambridge CB2 3EH, UK.
Current biology: CB (Impact Factor: 9.57). 10/2011; 21(20):R857-9. DOI: 10.1016/j.cub.2011.09.023
Source: PubMed


The mitotic exit network (MEN), a protein kinase cascade under the switch-like control of the small GTPase Tem1, triggers exit from mitosis in budding yeast. Now it emerges that signals from both Tem1 and the yeast Polo kinase Cdc5 converge onto the MEN kinase Cdc15 to accurately restrict MEN activation to late mitosis.

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    • "The process of cell separation is regulated by the RAM network (Regulation of Ace2 and Morphogenesis) (Saputo et al., 2012), whose activation is closely linked to the completion of mitosis and cytokinesis. In S. cerevisiae exit from mitosis and entry into cytokinesis is controlled by the Mitotic Exit Network (MEN) a GTPase regulated kinase cascade (reviewed in Bardin and Amon, 2001; de Bettignies and Johnston, 2003; McCollum and Gould, 2001; Segal, 2011). A similar cascade, the Septation Initiation Network (SIN), has been reported in Schizosaccharomyces pombe and Aspergillus nidulans, although in these organisms its primary role appears to be in regulating septation rather than mitotic exit (Bruno et al., 2001; Kim et al., 2006; Kim et al., 2009; Krapp et al., 2004). "
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