A new dominant peroxiredoxin allele identified by whole-genome re-sequencing of random mutagenized yeast causes oxidant-resistance and premature aging

Aging (Albany NY). 2010 Aug;2(8):475-86. doi: 10.18632/aging.100187.


The combination of functional genomics with next generation sequencing facilitates new experimental strategies for addressing complex biological phenomena. Here, we report the identification of a gain-of-function allele of peroxiredoxin (thioredoxin peroxidase, Tsa1p) via whole-genome re-sequencing of a dominantSaccharomyces cerevisiae mutant obtained by chemical mutagenesis. Yeast strain K6001, a screening system for lifespan phenotypes, was treated with ethyl methanesulfonate (EMS). We isolated an oxidative stress-resistant mutant (B7) which transmitted this phenotype in a background-independent, monogenic and dominant way. By massive parallel pyrosequencing, we generated an 38.8 fold whole-genome coverage of the strains, which differed in 12,482 positions from the reference (S288c) genome. Via a subtraction strategy, we could narrow this number to 13 total and 4 missense nucleotide variations that were specific for the mutant. Via expression in wild type backgrounds, we show that one of these mutations, exchanging a residue in the peroxiredoxin Tsa1p, was responsible for the mutant phenotype causing background-independent dominant oxidative stress-resistance. These effects were not provoked by altered Tsa1p levels, nor could they be simulated by deletion, haploinsufficiency or over-expression of the wild-type allele. Furthermore, via both a mother-enrichment technique and a micromanipulation assay, we found a robust premature aging phenotype of this oxidant-resistant strain. Thus, TSA1-B7 encodes for a novel dominant form of peroxiredoxin, and establishes a new connection between oxidative stress and aging. In addition, this study shows that the re-sequencing of entire genomes is becoming a promising alternative for the identification of functional alleles in approaches of classic molecular genetics.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alleles*
  • Animals
  • Base Sequence
  • Benzene Derivatives / toxicity
  • Cell Proliferation*
  • Ethyl Methanesulfonate / toxicity
  • Gene Expression
  • Genome, Fungal*
  • Haploinsufficiency
  • Mutagenesis
  • Mutagens / toxicity
  • Oxidants / toxicity
  • Oxidative Stress / genetics*
  • Peroxidases / genetics*
  • Phenotype
  • Saccharomyces cerevisiae / genetics
  • Saccharomyces cerevisiae / growth & development
  • Saccharomyces cerevisiae Proteins / genetics*
  • Sequence Analysis
  • Sequence Analysis, DNA


  • Benzene Derivatives
  • Mutagens
  • Oxidants
  • Saccharomyces cerevisiae Proteins
  • Ethyl Methanesulfonate
  • Peroxidases
  • Tsa1 protein, S cerevisiae
  • cumene hydroperoxide