Identification and dissection of a complex DNA repair sensitivity phenotype in Baker's yeast

PLoS Genet. 2008 Jul 11;4(7):e1000123. doi: 10.1371/journal.pgen.1000123.

Abstract

Complex traits typically involve the contribution of multiple gene variants. In this study, we took advantage of a high-density genotyping analysis of the BY (S288c) and RM strains of Saccharomyces cerevisiae and of 123 derived spore progeny to identify the genetic loci that underlie a complex DNA repair sensitivity phenotype. This was accomplished by screening hybrid yeast progeny for sensitivity to a variety of DNA damaging agents. Both the BY and RM strains are resistant to the ultraviolet light-mimetic agent 4-nitroquinoline 1-oxide (4-NQO); however, hybrid progeny from a BYxRM cross displayed varying sensitivities to the drug. We mapped a major quantitative trait locus (QTL), RAD5, and identified the exact polymorphism within this locus responsible for 4-NQO sensitivity. By using a backcrossing strategy along with array-assisted bulk segregant analysis, we identified one other locus, MKT1, and a QTL on Chromosome VII that also link to the hybrid 4-NQO-sensitive phenotype but confer more minor effects. This work suggests an additive model for sensitivity to 4-NQO and provides a strategy for mapping both major and minor QTL that confer background-specific phenotypes. It also provides tools for understanding the effect of genetic background on sensitivity to genotoxic agents.

MeSH terms

  • 4-Nitroquinoline-1-oxide / pharmacology
  • Adenosine Triphosphatases / genetics*
  • Adenosine Triphosphatases / metabolism
  • Chromosomes, Fungal / drug effects
  • Chromosomes, Fungal / genetics
  • Crosses, Genetic
  • DNA Damage / drug effects
  • DNA Helicases
  • DNA Repair / drug effects*
  • Genetic Linkage
  • Genome, Fungal
  • Microbial Sensitivity Tests
  • Mutagens / pharmacology*
  • Oligonucleotide Array Sequence Analysis
  • Phenotype
  • Polymorphism, Genetic
  • Quantitative Trait, Heritable
  • Saccharomyces cerevisiae / drug effects*
  • Saccharomyces cerevisiae / genetics*
  • Saccharomyces cerevisiae / metabolism
  • Saccharomyces cerevisiae Proteins / genetics*
  • Saccharomyces cerevisiae Proteins / metabolism
  • Spores, Fungal / drug effects
  • Spores, Fungal / genetics
  • Spores, Fungal / metabolism
  • Two-Hybrid System Techniques

Substances

  • MKT1 protein, S cerevisiae
  • Mutagens
  • Saccharomyces cerevisiae Proteins
  • 4-Nitroquinoline-1-oxide
  • Adenosine Triphosphatases
  • RAD5 protein, S cerevisiae
  • DNA Helicases