Role of the AtRad1p endonuclease in homologous recombination in plants.
Using a specific recombination assay, we show in the plant Arabidopsis thaliana that AtRad1 protein plays a role in the removal of non-homologous tails in homologous recombination. Recombination in the presence of non-homologous overhangs is reduced 11-fold in the atrad1 mutant compared with the wild-type plants. AtRad1p is the A. thaliana homologue of the human Xpf and Saccharomyces cerevisiae Rad1 proteins. Rad1p is a subunit of the Rad1p/Rad10p structure-specific endonuclease that acts in nucleotide excision repair and inter-strand crosslink repair. This endonuclease also plays a role in mitotic recombination to remove non-homologous, 3'-ended overhangs from recombination intermediates. The Arabidopsis atrad1 mutant (uvh1), unlike rad1 mutants known from other eukaryotes, is hypersensitive to ionizing radiation. This last observation may indicate a more important role for the Rad1/Rad10 endonuclease in recombination in plants. This is the first direct demonstration of the involvement of AtRad1p in homologous recombination in plants.
Dubest
Sandra
S
UMR 6547 BIOMOVE, Université Blaise Pascal, 24 ave. des Landais, 63177 Aubière, France.
Gallego
Maria E
ME
White
Charles I
CI
D000818:Animals; D017360:Arabidopsis / Q000235:genetics* / Q000378:metabolism / Q000528:radiation effects; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D004260:DNA Repair; D045643:DNA Repair Enzymes; D004268:DNA-Binding Proteins; D004720:Endonucleases / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D018515:Plant Leaves / Q000502:physiology; D011839:Radiation, Ionizing; D011995:Recombination, Genetic; D029701:Saccharomyces cerevisiae Proteins
D029681:Arabidopsis Proteins; D004268:DNA-Binding Proteins; D029701:Saccharomyces cerevisiae Proteins; D004720:Endonucleases; C069266:RAD1 protein, S cerevisiae; D045643:DNA Repair Enzymes