Homologous recombination in planta is stimulated in the absence of Rad50.
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.
Gherbi
H
H
UMR 6547 BIOMOVE, Université Blaise Pascal, 24 avenue des Landais, 63177 Aubière, France.
Gallego
M E
ME
Jalut
N
N
Lucht
J M
JM
Hohn
B
B
White
C I
CI
D000483:Alleles; D017360:Arabidopsis / Q000235:genetics; D004249:DNA Damage; D004260:DNA Repair; D004268:DNA-Binding Proteins; D005656:Fungal Proteins / Q000502:physiology*; D006579:Heterozygote; D008957:Models, Genetic; D009154:Mutation; D010641:Phenotype; D016133:Polymerase Chain Reaction; D011995:Recombination, Genetic; D029701:Saccharomyces cerevisiae Proteins
D004268:DNA-Binding Proteins; D005656:Fungal Proteins; C086930:RAD50 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins