The Arabidopsis UVH1 gene is a homolog of the yeast repair endonuclease RAD1.
Ultraviolet radiation induces DNA damage products, largely in the form of pyrimidine dimers, that are both toxic and mutagenic. In most organisms, including Arabidopsis, these lesions are repaired both through a dimer-specific photoreactivation mechanism and through a less efficient light-independent mechanism. Several mutants defective in this "dark repair" pathway have been previously described. The mechanism of this repair has not been elucidated, but is thought to be homologous to the nucleotide excision repair mechanisms found in other eukaryotes. Here we report the complementation of the Arabidopsis uvh1 dark repair mutant with the Arabidopsis homolog of the yeast nucleotide excision repair gene RAD1, which encodes one of the subunits of the 5'-repair endonuclease. The uvh1-2 mutant allele carries a glycine-->aspartate amino acid change that has been previously identified to produce a null allele of RAD1 in yeast. Although Arabidopsis homologs of genes involved in nucleotide excision repair are readily identified by searching the genomic database, it has not been established that these homologs are actually required for dark repair in plants. The complementation of the Arabidopsis uvh1 mutation with the Arabidopsis RAD1 homolog clearly demonstrates that the mechanism of nucleotide excision repair is conserved among the plant, animal, and fungal kingdoms.
Fidantsef
A L
AL
Section of Plant Biology, University of California, Davis, California 95616, USA.
Mitchell
D L
DL
Britt
A B
AB
D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000201:enzymology* / Q000235:genetics*; D029681:Arabidopsis Proteins; D001483:Base Sequence; D004249:DNA Damage; D017931:DNA Primers / Q000235:genetics; D004260:DNA Repair; D045643:DNA Repair Enzymes; D018744:DNA, Plant / Q000235:genetics; D004268:DNA-Binding Proteins; D004706:Endodeoxyribonucleases; D004720:Endonucleases / Q000235:genetics*; D017343:Genes, Plant; D005816:Genetic Complementation Test; D008969:Molecular Sequence Data; D009154:Mutation; D030821:Plants, Genetically Modified; D012441:Saccharomyces cerevisiae / Q000201:enzymology / Q000235:genetics; D029701:Saccharomyces cerevisiae Proteins; D017386:Sequence Homology, Amino Acid; D014466:Ultraviolet Rays
D029681:Arabidopsis Proteins; D017931:DNA Primers; D018744:DNA, Plant; D004268:DNA-Binding Proteins; D029701:Saccharomyces cerevisiae Proteins; D004706:Endodeoxyribonucleases; D004720:Endonucleases; C069266:RAD1 protein, S cerevisiae; C539269:XPF protein, Arabidopsis; D045643:DNA Repair Enzymes