Interaction between cdc13+ and cdc2+ in the control of mitosis in fission yeast; dissociation of the G1 and G2 roles of the cdc2+ protein kinase

EMBO J. 1987 Nov;6(11):3441-7.


A cold-sensitive (cs) allele of cdc2, a gene that acts in both the G1 and G2 phases of the fission yeast cell cycle, has been isolated by classical mutagenesis. Further mutagenesis of a cdc2cs strain yielded an extragenic suppressor that rescued the cs cell cycle defect but simultaneously conferred a temperature-sensitive (ts) cdc phenotype. This suppressor mutation was shown to be an allele of cdc13, a previously identified gene. A variety of allele-specific interactions between cdc2 and cdc13 were discovered. These included suppression of cdc13ts alleles by introduction of the cdc2+ gene on a multi-copy plasmid vector. cdc13+ is required in G2 for mitotic initiation and was shown to play no role in the G1 phase of the cell cycle. cdc2+, however, is essential in G1 for DNA replication and in G2 for mitosis. The newly isolated cs allele of cdc2 that is rescued by a ts allele of cdc13 is defective only in its G2 function. cdc13+ cooperates with cdc2+ in the initiation of mitosis but not in the regulation of DNA replication. We propose that the cdc13+ gene product might be a G2-specific substrate of the cdc2+ protein kinase.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Alleles
  • Cell Cycle
  • Crosses, Genetic
  • Genes, Fungal*
  • Genotype
  • Phenotype
  • Protein Kinases / genetics*
  • Saccharomycetales / genetics*
  • Schizosaccharomyces / cytology
  • Schizosaccharomyces / enzymology
  • Schizosaccharomyces / genetics*
  • Suppression, Genetic


  • Protein Kinases