title: Activation of Cdh1-dependent APC is required for G1 cell cycle arrest and DNA damage-induced G2 checkpoint in vertebrate cells.
abstract: Anaphase-promoting complex (APC) is activated by two regulatory proteins, Cdc20 and Cdh1. In yeast and Drosophila, Cdh1-dependent APC (Cdh1-APC) activity targets mitotic cyclins from the end of mitosis to the G1 phase. To investigate the function of Cdh1 in vertebrate cells, we generated clones of chicken DT40 cells disrupted in their Cdh1 loci. Cdh1 was dispensable for viability and cell cycle progression. However, similarly to yeast and Drosophila, loss of Cdh1 induced unscheduled accumulation of mitotic cyclins in G1, resulting in abrogation of G1 arrest caused by treatment with rapamycin, an inducer of p27(Kip1). Further more, we found that Cdh1(-/-) cells fail to maintain DNA damage-induced G2 arrest and that Cdh1-APC is activated by X-irradiation-induced DNA damage. Thus, activation of Cdh1-APC plays a crucial role in both cdk inhibitor-dependent G1 arrest and DNA damage-induced G2 arrest.
authors.affiliation: Department of Tumor Genetics and Biology, Kumamoto University School of Medicine, 2-2-1 Honjo, Kumamoto 860-0811, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Sudo
authors.forename: Y
authors.initials: Y
authors.lastname: Ota
authors.forename: S
authors.initials: S
authors.lastname: Kotani
authors.forename: M
authors.initials: M
authors.lastname: Nakao
authors.forename: Y
authors.initials: Y
authors.lastname: Takami
authors.forename: S
authors.initials: S
authors.lastname: Takeda
authors.forename: H
authors.initials: H
authors.lastname: Saya
mesh_terms: D064173:Anaphase-Promoting Complex-Cyclosome; D000818:Animals; D064199:Cdc20 Proteins; D018797:Cell Cycle Proteins / Q000037:antagonists & inhibitors / Q000378:metabolism; D002460:Cell Line; D002469:Cell Separation; D002645:Chickens; D003001:Cloning, Molecular; D050760:Cyclin-Dependent Kinase Inhibitor p27; D004249:DNA Damage; D018076:DNA, Complementary / Q000378:metabolism; D004330:Drosophila; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005434:Flow Cytometry; D005656:Fungal Proteins / Q000378:metabolism*; D016193:G1 Phase; D016195:G2 Phase; D008025:Ligases / Q000378:metabolism*; D008938:Mitosis; D011233:Precipitin Tests; D011485:Protein Binding; D020133:Reverse Transcriptase Polymerase Chain Reaction; D029701:Saccharomyces cerevisiae Proteins; D020123:Sirolimus / Q000494:pharmacology; D013997:Time Factors; D025521:Tumor Suppressor Proteins / Q000037:antagonists & inhibitors; D025801:Ubiquitin / Q000378:metabolism; D043743:Ubiquitin-Protein Ligase Complexes; D044767:Ubiquitin-Protein Ligases; D014965:X-Rays
chemical_list: C577495:CDC20 protein, S cerevisiae; D064199:Cdc20 Proteins; D018797:Cell Cycle Proteins; D018076:DNA, Complementary; D004791:Enzyme Inhibitors; D005656:Fungal Proteins; D029701:Saccharomyces cerevisiae Proteins; D025521:Tumor Suppressor Proteins; D025801:Ubiquitin; D050760:Cyclin-Dependent Kinase Inhibitor p27; D043743:Ubiquitin-Protein Ligase Complexes; D064173:Anaphase-Promoting Complex-Cyclosome; D044767:Ubiquitin-Protein Ligases; D008025:Ligases; D020123:Sirolimus