Cell cycle regulation of induced mutagenesis in yeast

Mutat Res. 1995 Jul;329(2):143-52. doi: 10.1016/0027-5107(95)00030-m.


The Saccharomyces cerevisiae CDC7 gene encodes a protein kinase that functions in three aspects of DNA metabolism: replication, repair, and meiotic recombination. It is likely that these functions overlap and share common elements. The cell cycle dependence of Cdc7 associated DNA repair was examined by UV irradiating a wild type and hypomutable cdc7-7 strain throughout the cell cycle. Both the wild type strain and the cdc7-7 mutant stain delay entry into S phase by 40-60 min when exposed to UV mutagenesis. Cells in G1 are the most sensitive to lethal UV damage while cells in S phase sustain fewer lethal hits. The yield of mutants is greatest for the CDC7 wild type strain when S phase cells are mutagenized. This peak of induced mutagenesis is absent in the cdc7-7 strain. Cdc7 protein may be required for error-prone DNA repair or for translesion error-prone DNA replication and not for the checkpoints in G1 phase. Because Cdc28 protein kinase and Dbf4 protein, a Cdc7 kinase regulator, are also important for induced mutagenesis and the CDC7 promoter is not induced in response to DNA damage, Cdc7 protein kinase may be regulated post-translationally following DNA damage, in the same manner as it is regulated during the cell cycle.

Publication types

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

MeSH terms

  • Cell Cycle / radiation effects*
  • Cell Cycle Proteins*
  • DNA Damage
  • DNA Repair
  • Fungal Proteins / genetics
  • G1 Phase / radiation effects
  • Mutagenesis*
  • Promoter Regions, Genetic / radiation effects
  • Protein Kinases / genetics
  • Protein Kinases / physiology*
  • Protein-Serine-Threonine Kinases*
  • Recombinant Fusion Proteins / biosynthesis
  • Saccharomyces cerevisiae / cytology*
  • Saccharomyces cerevisiae / genetics
  • Saccharomyces cerevisiae / radiation effects
  • Saccharomyces cerevisiae Proteins*
  • Ultraviolet Rays
  • beta-Galactosidase / biosynthesis
  • beta-Galactosidase / genetics


  • Cell Cycle Proteins
  • Dbf4 protein, S cerevisiae
  • Fungal Proteins
  • Recombinant Fusion Proteins
  • Saccharomyces cerevisiae Proteins
  • Protein Kinases
  • CDC7 protein, S cerevisiae
  • Protein-Serine-Threonine Kinases
  • beta-Galactosidase