title: The pachytene checkpoint in S. cerevisiae depends on Swe1-mediated phosphorylation of the cyclin-dependent kinase Cdc28.
abstract: Mutants defective in meiotic recombination and synaptonemal complex formation undergo checkpoint-mediated arrest in mid-meiotic prophase. In S. cerevisiae, this checkpoint requires Swe1, which phosphorylates and inactivates the cyclin-dependent kinase Cdc28. A swe1 deletion allows mutants that normally arrest in meiotic prophase to sporulate at wild-type levels, though sporulation is delayed. This delay is eliminated by overproducing Clb1, the major cyclin required for meiosis I. The Swe1 protein accumulates and is hyperphosphorylated in checkpoint-arrested cells. Our results suggest that meiotic arrest is mediated both by increasing Swe1 activity and limiting cyclin production, with Swe1 being the primary downstream target of checkpoint control. The requirement for Swe1 distinguishes the pachytene checkpoint from the DNA damage checkpoints operating in vegetative cells.
authors.affiliation: Department of Molecular, Cellular, and Developmental Biology, Yale University, New Haven, Connecticut 06520-8103, USA.
authors.forename: J Y
authors.initials: JY
authors.lastname: Leu
authors.forename: G S
authors.initials: GS
authors.lastname: Roeder
mesh_terms: D017489:CDC28 Protein Kinase, S cerevisiae / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D018797:Cell Cycle Proteins; D016213:Cyclins / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism; D004249:DNA Damage / Q000235:genetics; D004260:DNA Repair / Q000235:genetics; D005656:Fungal Proteins / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism; D015870:Gene Expression; D005800:Genes, Fungal / Q000235:genetics / Q000502:physiology; D008540:Meiosis / Q000235:genetics; D008954:Models, Biological; D009154:Mutation / Q000235:genetics; D010744:Phosphoric Monoester Hydrolases / Q000235:genetics / Q000378:metabolism; D010766:Phosphorylation; D011505:Protein-Tyrosine Kinases / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000166:cytology* / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development; D029701:Saccharomyces cerevisiae Proteins; D013172:Spores, Fungal / Q000201:enzymology / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D013489:Suppression, Genetic / Q000235:genetics; D013997:Time Factors; D015533:Transcriptional Activation / Q000235:genetics
chemical_list: D018797:Cell Cycle Proteins; D016213:Cyclins; D005656:Fungal Proteins; D012333:RNA, Messenger; D029701:Saccharomyces cerevisiae Proteins; C099685:SWE1 protein, S cerevisiae; D011505:Protein-Tyrosine Kinases; D017489:CDC28 Protein Kinase, S cerevisiae; D010744:Phosphoric Monoester Hydrolases