Regulation of Cdc2p and Cdc13p is required for cell cycle arrest induced by defective RNA splicing in fission yeast.
Screening of cdc mutants of fission yeast for those whose cell cycle arrest is independent of the DNA damage checkpoint identified the RNA splicing-deficient cdc28 mutant. A search for mutants of cdc28 cells that enter mitosis with unspliced RNA resulted in the identification of an orb5 point mutant. The orb5+ gene, which encodes a catalytic subunit of casein kinase II, was found to be required for cell cycle arrest in other mutants with defective RNA metabolism but not for operation of the DNA replication or DNA damage checkpoints. Loss of function of wee1+ or rad24+ also suppressed the arrest of several splicing mutants. Overexpression of the major B-type cyclin Cdc13p induced cdc28 cells to enter mitosis. The abundance of Cdc13p was reduced, and the phosphorylation of Cdc2p on tyrosine 15 was maintained in splicing-defective cells. These results suggest that regulation of Cdc13p and Cdc2p is required for G2 arrest in splicing mutants.
Shimada
Midori
M
Department of Biochemistry and Cell Biology, Graduate School of Medicine, Nagoya City University, 1 Kawasumi, Mizuho-cho, Mizuho-ku, Nagoya 467-8601, Japan.
Namikawa-Yamada
Chisato
C
Nakanishi
Makoto
M
Murakami
Hiroshi
H
D017398:Alternative Splicing; D015152:Blotting, Northern; D016203:CDC2 Protein Kinase / Q000096:biosynthesis* / Q000235:genetics; D017489:CDC28 Protein Kinase, S cerevisiae / Q000235:genetics; D047390:Casein Kinase II / Q000378:metabolism; D002453:Cell Cycle; D018797:Cell Cycle Proteins / Q000235:genetics; D002460:Cell Line; D002470:Cell Survival; D019926:Cyclin B / Q000096:biosynthesis* / Q000235:genetics; D004247:DNA / Q000378:metabolism; D004249:DNA Damage; D016195:G2 Phase; D015966:Gene Expression Regulation, Fungal; D005838:Genotype; D015151:Immunoblotting; D047908:Intracellular Signaling Peptides and Proteins / Q000235:genetics; D008938:Mitosis; D009154:Mutation; D009687:Nuclear Proteins / Q000235:genetics; D010766:Phosphorylation; D017354:Point Mutation; D011505:Protein-Tyrosine Kinases / Q000235:genetics; D012313:RNA / Q000378:metabolism; D012326:RNA Splicing; D012568:Schizosaccharomyces / Q000235:genetics*; D029702:Schizosaccharomyces pombe Proteins / Q000096:biosynthesis* / Q000235:genetics / Q000378:metabolism; D013997:Time Factors
C498823:Cdc13 protein, S pombe; D018797:Cell Cycle Proteins; D019926:Cyclin B; D047908:Intracellular Signaling Peptides and Proteins; D009687:Nuclear Proteins; D029702:Schizosaccharomyces pombe Proteins; C501114:rad24 protein, S pombe; D012313:RNA; D004247:DNA; C068689:wee1 protein, S pombe; D011505:Protein-Tyrosine Kinases; D047390:Casein Kinase II; C479661:casein kinase II, S pombe; D016203:CDC2 Protein Kinase; D017489:CDC28 Protein Kinase, S cerevisiae; C469447:cdc2 protein, S pombe