AtRAD1, a plant homologue of human and yeast nucleotide excision repair endonucleases, is involved in dark repair of UV damages and recombination

• Published in: The Plant journal : for cell and molecular biology Vol. 21; no. 6; pp. 507 - 518
• Main Authors: Gallego, Francesca, Fleck, Oliver, Li, Anatoliy, Wyrzykowska, Joanna, Tinland, Bruno
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Science Ltd 01.03.2000; Blackwell Science
• Subjects: Amino Acid Sequence; Arabidopsis - genetics; Arabidopsis thaliana; AtRAD1 gene; Biological and medical sciences; deoxyribonuclease; DNA - radiation effects; DNA Damage; DNA Repair; DNA Repair Enzymes; DNA, Complementary - chemistry; DNA-Binding Proteins; Down-Regulation; Endonucleases - metabolism; Exonucleases - metabolism; Fundamental and applied biological sciences. Psychology; Humans; Molecular and cellular biology; Molecular genetics; Molecular Sequence Data; Mutagenesis. Repair; nucleotide excision repair; Oligonucleotides, Antisense - metabolism; Open Reading Frames; Recombination, Genetic; Saccharomyces cerevisiae - genetics; Saccharomyces cerevisiae Proteins; Schizosaccharomyces - genetics; Schizosaccharomyces pombe Proteins; Ultraviolet Rays; Yeast; Excision; Enzyme; Esterases; Structure function relationship; Fungi; Arabidopsis thaliana; Characterization; Ultraviolet radiation; Cruciferae; Dicotyledones; DNA; Angiospermae; Hydrolases; Isolation; Ascomycetes; Spermatophyta; Experimental plant; Repair; Saccharomyces cerevisiae; Thallophyta
• ISSN: 0960-7412; 1365-313X
• DOI: 10.1046/j.1365-313x.2000.00694.x

Summary Plants are unique in the obligatory nature of their exposure to sunlight and consequently to ultraviolet (UV) irradiation. However, our understanding of plant DNA repair processes lags far behind the current knowledge of repair mechanisms in microbes, yeast and mammals, especially concerning the universally conserved and versatile dark repair pathway called nucleotide excision repair (NER). Here we report the isolation and functional characterization of Arabidopsis thaliana AtRAD1, which encodes the plant homologue of Saccharomyces cerevisiae RAD1, Schizosaccharomyces pombe RAD16 and human XPF, endonucleolytic enzymes involved in DNA repair and recombination processes. Our results indicate that AtRAD1 is involved in the excision of UV‐induced damages, and allow us to assign, for the first time in plants, the dark repair of such DNA lesions to NER. The low efficiency of this repair mechanism, coupled to the fact that AtRAD1 is ubiquitously expressed including tissues that are not accessible to UV light, suggests that plant NER has other roles. Possible ‘UV‐independent’ functions of NER are discussed with respect to features that are particular to plants.