Cdc20, an Activator at Last

Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA 94115, USA.
Molecular cell (Impact Factor: 14.02). 12/2008; 32(4):460-1. DOI: 10.1016/j.molcel.2008.11.006
Source: PubMed


Cdc20 was first identified as an essential gene required for the metaphase-to-anaphase transition in yeast. Subsequent work suggested that the Drosophila Cdc20 homolog, Fizzy, was required for the turnover of mitotic cyclins (reviewed in Thornton and Toczyski, 2006). It soon became apparent that Fizzy/Cdc20 and a similar protein, Fizzy-related/Cdh1, promoted anaphase-promoting complex (APC) function, although the mechanism by which it did this was not clear. What was clear early on, however, was that the regulation of APC activity on its substrates relied largely on the regulation of Cdc20 and Cdh1. Thus, not only were these molecules required for APC function, they were also the targets of its regulation, either by their degradation, their phosphorylation, or the binding of protein inhibitors. Now, Kimata et al. (2008) have exploited an unusual APC substrate, Nek2A, which they had previously shown interacts directly with the core APC independently of Cdc20, to identify a previously unappreciated role for Cdc20 in direct APC activation.

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