Dual functions of CDC6: a yeast protein required for DNA replication also inhibits nuclear division

EMBO J. 1992 Jun;11(6):2167-76.


The Saccharomyces cerevisiae gene CDC6, whose protein product is required for DNA replication, is transcribed only in late G1 and S phases. We have discovered a critical reason why CDC6 expression is regulated in this fashion. Constitutive CDC6 transcription greatly delayed the initiation of M phase without effecting the G1-S transition or growth rate. This occurred in both fission and budding yeasts. The CDC6-induced M phase delay was dependent on the wee1/mik1 mitotic inhibitor kinases and was greatly accentuated in strains defective for the cdc25/MIH1 mitotic inducer phosphatases, indicating that CDC6 indirectly inhibits activation of the p34cdc2/CDC28 M phase kinase. Thus CDC6 appears to have an important and perhaps unique dual role in S phase, it is first required for the initiation of DNA replication and then actively participates in the suppression of nuclear division.

Publication types

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

MeSH terms

  • Base Sequence
  • Cell Cycle / drug effects
  • Cell Cycle / genetics*
  • Cell Cycle Proteins*
  • Cell Division
  • Cell Nucleus / physiology*
  • Cell Nucleus / ultrastructure
  • DNA Replication / genetics*
  • Fungal Proteins / genetics*
  • Fungal Proteins / metabolism*
  • Genes, Fungal*
  • Mating Factor
  • Mitosis / genetics
  • Molecular Sequence Data
  • Oligodeoxyribonucleotides
  • Peptides / pharmacology
  • Pheromones / pharmacology
  • Plasmids
  • Protein Tyrosine Phosphatases / genetics
  • Protein Tyrosine Phosphatases / metabolism
  • Saccharomyces cerevisiae / cytology
  • Saccharomyces cerevisiae / genetics*
  • Saccharomyces cerevisiae / physiology
  • Saccharomyces cerevisiae Proteins*
  • Transcription, Genetic*
  • ras-GRF1*


  • CDC6 protein, S cerevisiae
  • Cell Cycle Proteins
  • Fungal Proteins
  • Oligodeoxyribonucleotides
  • Peptides
  • Pheromones
  • Saccharomyces cerevisiae Proteins
  • ras-GRF1
  • Mating Factor
  • Protein Tyrosine Phosphatases