Before and after the spindle assembly checkpoint: An APC/C Point of View

The Laboratory of Molecular and Cellular Biology, the National Institute of Diabetes and Digestive and Kidney Diseases, the National Institutes of Health, Bethesda, Maryland 20892-0840, USA.
Cell cycle (Georgetown, Tex.) (Impact Factor: 4.57). 10/2006; 5(18):2168-71.
Source: PubMed


On May 17-21, 2006 the Cold Spring Harbor Laboratory meeting on the cell cycle reunited over 350 researchers to discuss new findings in the cell cycle field. A common thread that connected numerous presentations was the regulation of the anaphase promoting complex/cyclosome (APC/C). This was also the main theme of the lecture given by the keynote speaker, Marc Kirschner (Harvard), who talked about "The unexpected importance of UbcH10 in both the G(1)/S transition and the initiation of anaphase", and it is also the main focus in this summary.

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    • "In late mitosis, Cdc20 is degraded by Cdh1/APC and leads to the complete replacement of Cdc20/APC by Cdh1/APC [7,8]. Recent studies demonstrated that UbcH10 supplementation promotes dissociation of the spindle assembly checkpoint proteins Mad2 and BubR1 from Cdc20, and then activates Cdc20/APC, which leads to cyclin A and securin degradation [9,10]. These results suggest that UbcH10 is potentially involved in the termination of the spindle assembly checkpoint and further implies that aberrant UbcH10 expression impairs the spindle assembly checkpoint resulting in chromosomal instability [11,12]. "
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