Cdc14 and the temporal coordination between mitotic exit and chromosome segregation

Abstract

Cell division involves the inheritance of a complete set of the genome in the form of chromosomes. One of the strategies employed by eukaryotic cells is to maintain replicated sister chromatids together until the anaphase onset. A protein complex named cohesin holds sisters together following replication until anaphase when cleavage of cohesin by the protease separase initiates segregation. Recent studies in budding yeast have shown that cohesin cleavage alone is not sufficient for the segregation of the entire genome. Instead, repetitive regions, such as the ribosomal DNA (rDNA) array and telomeres, require additional mechanisms during mitotic disjunction. The segregation of such chromosome regions is delayed and needs specific cell cycle regulators such as the FEAR network and the conserved phosphatase Cdc14, all of which orchestrate the timely completion of chromosome segregation before mitotic exit. Future studies will be targeted towards unravelling the nature of the additional segregation requirements for repetitive regions and the specifics of its cell cycle control. ©2005 Landes Bioscience.