Mating-type suppression of the DNA-repair defect of the yeast rad6 delta mutation requires the activity of genes in the RAD52 epistasis group

Curr Genet. 1995 Jun;28(1):12-8. doi: 10.1007/BF00311876.


The RAD6 gene of Saccharomyces cerevisiae is required for post-replication repair of UV-damaged DNA, UV mutagenesis, and sporulation. Here, we show that the radiation sensitivity of a MATa rad6 delta strain can be suppressed by the MAT alpha 2 gene carried on a multicopy plasmid. The a1-alpha 2 suppression is specific to the RAD6 pathway, as mutations in genes required for nucleotide excision repair or for recombinational repair do not show such mating-type suppression. The a1-alpha 2 suppression of the rad6 delta mutation requires the activity of the RAD52 group of genes, suggesting that suppression occurs by channelling of post-replication gaps present in the rad6 delta mutant into the RAD52 recombinational repair pathway. The a1-alpha 2 repressor could mediate this suppression via an enhancement in the expression, or the activity, of recombination genes.

Publication types

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

MeSH terms

  • DNA Damage
  • DNA Repair / genetics*
  • DNA Replication
  • DNA-Binding Proteins / genetics*
  • Epistasis, Genetic
  • Fungal Proteins / genetics*
  • Ligases / genetics*
  • Mutation
  • Plasmids
  • Rad52 DNA Repair and Recombination Protein
  • Radiation Tolerance / genetics
  • Saccharomyces cerevisiae / genetics*
  • Saccharomyces cerevisiae / radiation effects
  • Saccharomyces cerevisiae Proteins*
  • Ubiquitin-Conjugating Enzymes
  • Ultraviolet Rays


  • DNA-Binding Proteins
  • Fungal Proteins
  • RAD52 protein, S cerevisiae
  • Rad52 DNA Repair and Recombination Protein
  • Saccharomyces cerevisiae Proteins
  • RAD6 protein, S cerevisiae
  • Ubiquitin-Conjugating Enzymes
  • Ligases