Early expressed Clb proteins allow accumulation of mitotic cyclin by inactivating proteolytic machinery during S phase.
Periodic accumulation and destruction of mitotic cyclins are important for the initiation and termination of M phase. It is known that both APC(Cdc20) and APC(Hct1) collaborate to destroy mitotic cyclins during M phase. Here we show that this relationship between anaphase-promoting complex (APC) and Clb proteins is reversed in S phase such that the early Clb kinases (Clb3, Clb4, and Clb5 kinases) inactivate APC(Hct1) to allow Clb2 accumulation. This alternating antagonism between APC and Clb proteins during S and M phases constitutes an oscillatory system that generates undulations in the levels of mitotic cyclins.
Yeong
F M
FM
Institute of Molecular and Cell Biology, Singapore 117609, Singapore.
Lim
H H
HH
Wang
Y
Y
Surana
U
U
D064173:Anaphase-Promoting Complex-Cyclosome; D015152:Blotting, Northern; D015153:Blotting, Western; D064199:Cdc20 Proteins; D064200:Cdh1 Proteins; D018797:Cell Cycle Proteins / Q000378:metabolism; D019926:Cyclin B / Q000378:metabolism*; D016213:Cyclins / Q000378:metabolism*; D005434:Flow Cytometry; D005656:Fungal Proteins / Q000378:metabolism; D017353:Gene Deletion; D008025:Ligases / Q000378:metabolism; D008856:Microscopy, Fluorescence; D008938:Mitosis; D008954:Models, Biological; D009154:Mutation; D010766:Phosphorylation; D010957:Plasmids / Q000378:metabolism; D011485:Protein Binding; D016196:S Phase; D029701:Saccharomyces cerevisiae Proteins; D013997:Time Factors; D014158:Transcription, Genetic; D043743:Ubiquitin-Protein Ligase Complexes; D044767:Ubiquitin-Protein Ligases; D015003:Yeasts / Q000378:metabolism
C577495:CDC20 protein, S cerevisiae; C577583:CDH1 protein, S cerevisiae; C093749:CLB2 protein, S cerevisiae; D064199:Cdc20 Proteins; D064200:Cdh1 Proteins; D018797:Cell Cycle Proteins; D019926:Cyclin B; D016213:Cyclins; D005656:Fungal Proteins; D029701:Saccharomyces cerevisiae Proteins; D043743:Ubiquitin-Protein Ligase Complexes; D064173:Anaphase-Promoting Complex-Cyclosome; D044767:Ubiquitin-Protein Ligases; D008025:Ligases