title: Transcriptional and post-transcriptional regulation of Cdc20 during the spindle assembly checkpoint in S. cerevisiae.
abstract: The anaphase-promoting complex (APC) is a ubiquitin ligase responsible for promoting the degradation of many cell cycle regulators. One of the activators and substrate-binding proteins for the APC is Cdc20. It has been shown previously that Cdc20 can promote its own degradation by the APC in normal cycling cells mainly through a cis-degradation mode (i.e. via an intramolecular mechanism). However, how Cdc20 is degraded during the spindle assembly checkpoint (SAC) is still not fully clear. In this study, we used a dual-Cdc20 system to investigate this issue and found that the cis-degradation mode is also the major pathway responsible for Cdc20 degradation during the SAC. In addition, we found that there is an inverse relationship between APCCdc20activity and the transcriptional activity of the CDC20 promoter, which likely occurs through feedback regulation by APCCdc20substrates, such as the cyclins Clb2 and Clb5. These findings contribute to our understanding of how the inhibition of APCCdc20activity and enhanced Cdc20 degradation are required for proper spindle checkpoint arrest.
authors.affiliation: Institute of Life Sciences, College of Biological Science and Engineering, Fuzhou University, Fuzhou, Fujian Province 350108, China. Electronic address: ruiwen.wang@fzu.edu.cn.
authors.forename: Ruiwen
authors.initials: R
authors.lastname: Wang
authors.affiliation: Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06520-8114, USA.
authors.forename: Janet L
authors.initials: JL
authors.lastname: Burton
authors.affiliation: Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06520-8114, USA. Electronic address: Mark.Solomon@Yale.edu.
authors.forename: Mark J
authors.initials: MJ
authors.lastname: Solomon
mesh_terms: D020816:Amino Acid Motifs; D064173:Anaphase-Promoting Complex-Cyclosome / Q000378:metabolism; D064199:Cdc20 Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D015966:Gene Expression Regulation, Fungal; D059566:M Phase Cell Cycle Checkpoints / Q000235:genetics*; D011401:Promoter Regions, Genetic / Q000235:genetics; D059748:Proteolysis; D012441:Saccharomyces cerevisiae / Q000166:cytology* / Q000235:genetics*; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D013379:Substrate Specificity; D014158:Transcription, Genetic
chemical_list: C577495:CDC20 protein, S cerevisiae; D064199:Cdc20 Proteins; D029701:Saccharomyces cerevisiae Proteins; D064173:Anaphase-Promoting Complex-Cyclosome
keywords: Anaphase-promoting complex; Cdc20; Post-transcriptional regulation; Protein degradation; Spindle assembly checkpoint; Ubiquitination