InterPro domain: IPR027097

Mad2 is a central component of the spindle assembly checkpoint, which is a feedback control that prevents cells with incompletely assembled spindles from leaving mitosis [ 1 , 2 ]. In Saccharomyces cerevisiae, it is a component of the mitotic checkpoint complex (MCC) which consists of MAD2, MAD3, BUB3 and CDC20, and of the MAD2-CDC20 subcomplex, both of which appear to be assembled during mitoisis independently of the kinetochore. MCC and presumably the MAD2-CDC20 subcomplex inhibit the ubiquitin ligase activity of the anaphase promoting complex/cyclosome (APC/C) by preventing its activation by CDC20 [ 3 , 3 , 4 ].

1. The mitotic feedback control gene MAD2 encodes the alpha-subunit of a prenyltransferase. Nature 366, 82-4
2. Two complexes of spindle checkpoint proteins containing Cdc20 and Mad2 assemble during mitosis independently of the kinetochore in Saccharomyces cerevisiae. Eukaryotic Cell 4, 867-78
3. Bub3 interaction with Mad2, Mad3 and Cdc20 is mediated by WD40 repeats and does not require intact kinetochores. EMBO J. 20, 6648-59
4. The spindle checkpoint of budding yeast depends on a tight complex between the Mad1 and Mad2 proteins. Mol. Biol. Cell 10, 2607-18