The  S. pombe  CDK5 Orthologue Pef1 Cooperates with Three Cyclins, Clg1, Pas1 and Psl1, to Promote Pre-Meiotic DNA Replication.
Meiosis is a specialized cell division process that mediates genetic information transfer to the next generation. Meiotic chromosomal segregation occurs when DNA replication is completed during the pre-meiotic S phase. Here, we show that  Schizosaccharomyces pombe  Pef1, an orthologue of mammalian cyclin-dependent kinase 5 (CDK5), is required to promote pre-meiotic DNA replication. We examined the efficiency of meiotic initiation using  pat1-114  mutants and found that, meiotic nuclear divisions did not occur in the  pef1Δ pat1-114  strain. Deletion of  pef1  also suppressed the expression of DNA replication factors and the phosphorylation of Cdc2 Tyr-15. The double deletion of  clg1  and  psl1  arrested meiotic initiation in  pat1-114  mutant cells, similar to that of  pef1 -deficient cells. Meiotic progression was also slightly delayed in the  pas1 -deficient strain. Our results reveal that Pef1 regulates cyclin-coordinated meiotic progression.
Matsuda S, Kikkawa U, Nakashima A