Homologous recombination in planta is stimulated in the absence of Rad50

EMBO Rep. 2001 Apr;2(4):287-91. doi: 10.1093/embo-reports/kve069.


Chromosomal double-strand DNA breaks must be repaired; in the absence of repair the resulting acentromeric (and telomereless) fragments may be lost and/or the broken DNA ends may recombine causing general chromosomal instability. The Rad50/Mre11/Xrs2 protein complex acts at DNA ends and is implicated in both homologous and non-homologous recombination. We have isolated a rad50 mutant of the plant Arabidopsis thaliana and show here that it has a somatic hyper-recombination phenotype in planta. This finding supports the hypothesis of a competition between homologous and illegitimate recombination in higher eukaryotes. To our knowledge, this is the first direct in vivo support for the role of this complex in chromosomal recombination in a multicellular organism and the first description of a mutation of a known gene leading to hyper-recombination in plants.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alleles
  • Arabidopsis / genetics
  • DNA Damage*
  • DNA Repair*
  • DNA-Binding Proteins*
  • Fungal Proteins / physiology*
  • Heterozygote
  • Models, Genetic
  • Mutation
  • Phenotype
  • Polymerase Chain Reaction
  • Recombination, Genetic*
  • Saccharomyces cerevisiae Proteins*


  • DNA-Binding Proteins
  • Fungal Proteins
  • RAD50 protein, S cerevisiae
  • Saccharomyces cerevisiae Proteins