Apc3, otherwise known as Cdc27, is one of the subunits of the anaphase-promoting complex or cyclosome. The anaphase-promoting complex is a multiprotein subunit E3 ubiquitin ligase complex that controls segregation of chromosomes and exit from mitosis in eukaryotes [1, 2]. The protein members of this family contain TPR repeats just as those of Apc7 do, and it appears that these TPR units bind the C-termini of the APC co-activators CDH1 and CDC20 [3].

1: The anaphase-promoting complex: proteolysis in mitosis and beyond. Peters JM; Mol Cell. 2002;9:931-943. PMID:12049731

2: The anaphase promoting complex/cyclosome: a machine designed to destroy. Peters JM; Nat Rev Mol Cell Biol. 2006;7:644-656. PMID:16896351

3: TPR subunits of the anaphase-promoting complex mediate binding to the activator protein CDH1. Vodermaier HC, Gieffers C, Maurer-Stroh S, Eisenhaber F, Peters JM; Curr Biol. 2003;13:1459-1468. PMID:12956947