Multiple branches of the meiotic recombination pathway contribute independently to homolog pairing and stable juxtaposition during meiosis in budding yeast

Genes Dev. 2005 Apr 1;19(7):863-74. doi: 10.1101/gad.1293605.

Abstract

A unique aspect of meiosis is the segregation of homologous chromosomes at the meiosis I division. Homologs are physically connected prior to segregation by crossing over between nonsister chromatids. Crossovers arise from the repair of induced double-strand breaks (DSBs). In many organisms, more DSBs are formed than crossovers in a given nucleus. It has been previously suggested that repair of DSBs to noncrossover recombination products aids homolog alignment. Here we explore how two modes of the meiotic recombination pathway (crossover and noncrossover) and meiotic telomere reorganization contribute to the pairing and close juxtaposition of homologous chromosomes in budding yeast. We found that intermediates in the DSB repair pathway leading to both crossover and noncrossover recombination products contribute independently to close, stable homolog juxtaposition (CSHJ), a measurable state of homolog pairing. Analysis of the ndj1delta mutant indicates that the effect of meiotic telomere reorganization on CSHJ is exerted through recombination intermediates at interstitial chromosomal loci, perhaps through the noncrossover branch of the DSB repair pathway. We suggest that transient, early DSB-initiated interactions, including those that give rise to noncrossovers, are important for homolog recognition and juxtaposition.

Publication types

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

MeSH terms

  • Cell Cycle Proteins / genetics
  • Chromosome Pairing / genetics
  • Chromosome Pairing / physiology*
  • Crossing Over, Genetic / genetics
  • Crossing Over, Genetic / physiology*
  • DNA Helicases / genetics
  • DNA-Binding Proteins / genetics
  • Endodeoxyribonucleases
  • Endonucleases / genetics
  • Epistasis, Genetic
  • Esterases / genetics
  • Mutation
  • Nuclear Proteins
  • Saccharomyces cerevisiae Proteins / genetics
  • Saccharomycetales / genetics
  • Saccharomycetales / physiology*
  • Temperature

Substances

  • Cell Cycle Proteins
  • DNA-Binding Proteins
  • Ndj1 protein, S cerevisiae
  • Nuclear Proteins
  • Saccharomyces cerevisiae Proteins
  • Zip1 protein, S cerevisiae
  • Endodeoxyribonucleases
  • Endonucleases
  • Esterases
  • MUS81 protein, S cerevisiae
  • meiotic recombination protein SPO11
  • HFM1 protein, S cerevisiae
  • DNA Helicases