RCC1-Ran-RanGAP Signal for Initiation of Mitosis
In most eukaryotic cells checkpoints ensure that DNA replication is completed before the onset of mitosis. Experimentally these controls can be overrun, e.g., by fusion of S-phase cells with mitotic cells (Johnson and Rao, 1970), by adding 5 mM caffeine (Schlegel and Pardee, 1986) to the medium of S-phase cells, or by okadaic acid (Yamashita et al., 1990), resulting in premature condensation of the chromosomes and in their ‘pulverized’ appearance under the microscope.
KeywordsOkadaic Acid Chromosome Condensation Premature Chromosome Condensation Mitotic Control p34Cdc2 Kinase
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