Specialized roles of the two mitotic cyclins in somatic cells: cyclin A as an activator of M phase-promoting factor.

@article{Fung2007SpecializedRO,
  title={Specialized roles of the two mitotic cyclins in somatic cells: cyclin A as an activator of M phase-promoting factor.},
  author={T. Fung and H. T. Ma and R. Poon},
  journal={Molecular biology of the cell},
  year={2007},
  volume={18 5},
  pages={
          1861-73
        }
}
The role of cyclin B-CDC2 as M phase-promoting factor (MPF) is well established, but the precise functions of cyclin A remain a crucial outstanding issue. Here we show that down-regulation of cyclin A induces a G2 phase arrest through a checkpoint-independent inactivation of cyclin B-CDC2 by inhibitory phosphorylation. The phenotype is rescued by expressing cyclin A resistant to the RNA interference. In contrast, down-regulation of cyclin B disrupts mitosis without inactivating cyclin A-CDK… Expand
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