Functions of the Cdc14-Family Phosphatase Clp1p in the Cell Cycle Regulation of Schizosaccharomyces pombe : A Dissertation

摘要: In order to generate healthy daughter cells, nuclear division and cytokinesis need be coordinated. Premature of the cytoplasm in absence chromosome segregation or proliferation without might lead aneuploidy cancer. The cyclin dependent kinases, CDKs, are a main regulator cell cycle. Timely increase decrease their activity is required for cycle progression. To enter mitosis, mitotic CDK needs rise. stays elevated until completed exit from mitosis requires activity. Observations several experimental systems suggest that coordination with regulated through Prolonged high activity, as it occurs when delayed, was found oppose cytokinesis. Prevention may therefore provide mechanism prevent precocious segregation. polyploidy progression next should inhibited completed, presumably by inhibition fission yeast Schizosaccharomyces pombe, signaling cascade called Septation Initiation Network (SIN) SIN essential cytokinesis, triggering execution constriction actomyosin ring. activation cascade, thus opposed preventing S. pombe delay entry into response delayed due defects contractile ring thereby accumulation multinucleate, non viable cells. This safeguard against multinucleate cells termed checkpoint. checkpoint keeps low, key coordinator between How functions not known. Cdc14-family phosphatases highly conserved humans, but were only characterized Saccharomyces cerevisiae at time this thesis initiated. Cdc14 had been identified effector homologous SIN, network (MEN), which mitosis. describes identification Cdc14-like phosphatase Clp1p component opposes activate each other positive feedback loop. maintains an active delays entry. We further regulates Concluding, discoveries adding the…