title: Meiosis-specific destruction of the Ume6p repressor by the Cdc20-directed APC/C.
abstract: Meiotic development in yeast requires the coordinated induction of transient waves of gene transcription. The present study investigates the regulation of Ume6p, a mitotic repressor of the "early" class of meiosis-specific genes. Western blot analysis revealed that Ume6p is destroyed early in meiosis by Cdc20p, an activator of the anaphase-promoting complex/cyclosome (APC/C) ubiquitin ligase. This control appears direct as Cdc20p and Ume6p associate in vivo and APC/C(Cdc20) ubiquitylates Ume6p in vitro. Inactivating Cdc20p, or stabilizing Ume6p through mutation, prevented meiotic gene transcription and meiotic progression. During mitotic cell division, Ume6p is protected from destruction by protein kinase A phosphorylation of Cdc20p. Complete elimination of Ume6p in meiotic cells requires association with the meiotic inducer Ime1p. These results indicate that Ume6p degradation is required for normal meiotic gene induction and meiotic progression. These findings demonstrate a direct connection between the transcription machinery and ubiquitin-mediated proteolysis that is developmentally regulated.
authors: Institute for Cancer Research, Fox Chase Cancer Center, Philadelphia, PA 19111, USA.
authors: Michael J
authors: MJ
authors: Mallory
authors: Katrina F
authors: KF
authors: Cooper
authors: Randy
authors: R
authors: Strich
mesh_terms: D000595:Amino Acid Sequence; D064173:Anaphase-Promoting Complex-Cyclosome; D002244:Carbon / Q000378:metabolism; D064199:Cdc20 Proteins; D018797:Cell Cycle Proteins / Q000378:metabolism*; D000242:Cyclic AMP / Q000378:metabolism; D017868:Cyclic AMP-Dependent Protein Kinases / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D015536:Down-Regulation / Q000235:genetics; D005800:Genes, Fungal; D008540:Meiosis; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000378:metabolism; D010766:Phosphorylation; D011485:Protein Binding; D011499:Protein Processing, Post-Translational; D012097:Repressor Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000166:cytology* / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D013379:Substrate Specificity; D014157:Transcription Factors / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D014158:Transcription, Genetic; D043743:Ubiquitin-Protein Ligase Complexes / Q000378:metabolism*; D018631:ras Proteins / Q000378:metabolism
chemical_list: C577495:CDC20 protein, S cerevisiae; D064199:Cdc20 Proteins; D018797:Cell Cycle Proteins; D004268:DNA-Binding Proteins; C080326:IME1 protein, S cerevisiae; D009687:Nuclear Proteins; D012097:Repressor Proteins; D029701:Saccharomyces cerevisiae Proteins; D014157:Transcription Factors; C089979:UME6 protein, S cerevisiae; D002244:Carbon; D000242:Cyclic AMP; D043743:Ubiquitin-Protein Ligase Complexes; D064173:Anaphase-Promoting Complex-Cyclosome; D017868:Cyclic AMP-Dependent Protein Kinases; D018631:ras Proteins