Nucleotide excision repair endonuclease genes in Drosophila melanogaster.
Nucleotide excision repair (NER) is the primary pathway for the removal of ultraviolet light-induced damage and bulky adducts from DNA in eukaryotes. During NER, the helix is unwound around the damaged site, and incisions are made on the 5' and 3' sides, to release an oligonucleotide carrying the lesion. Repair synthesis can then proceed, using the intact strand as a template. The incisions flanking the lesion are catalyzed by different structure-specific endonucleases. The 5' incision is made by a heterodimer of XPF and ERCC1 (Rad1p-Rad10p in Saccharomyces cerevisiae), and the 3' incision is made by XPG (Rad2p in S. cerevisiae). We previously showed that the Drosophila XPF homologue is encoded by the meiotic recombination gene mei-9. We report here the identification of the genes encoding the XPG and ERCC1 homologues (XPG(Dm) and ERCC1(Dm)). XPG(Dm) is encoded by the mus201 gene; we found frameshift mutations predicted to produce truncated XPG(Dm) proteins in each of two mus201 alleles. These mutations cause defects in nucleotide excision repair and hypersensitivity to alkylating agents and ultraviolet light, but do not cause hypersensitivity to ionizing radiation and do not impair viability or fertility. ERCC1(Dm) interacts strongly in a yeast two-hybrid assay with MEI-9, indicative of the presumed requirement for these polypeptides to dimerize to form the functional endonuclease. The Drosophila Ercc1 gene maps to polytene region 51D1-2. The nucleotide excision repair gene mus210 maps nearby (51E-F) but is distinct from Ercc1.
Sekelsky
J J
JJ
Department of Genetics, Section of Molecular and Cellular Biology, University of California, Davis, CA 95616, USA. sekelsky@unc.edu
Hollis
K J
KJ
Eimerl
A I
AI
Burtis
K C
KC
Hawley
R S
RS
D000483:Alleles; D000595:Amino Acid Sequence; D000818:Animals; D002874:Chromosome Mapping; D004260:DNA Repair / Q000235:genetics*; D004268:DNA-Binding Proteins / Q000235:genetics*; D029721:Drosophila Proteins; D004331:Drosophila melanogaster / Q000201:enzymology / Q000235:genetics*; D004706:Endodeoxyribonucleases / Q000235:genetics; D004720:Endonucleases / Q000235:genetics*; D005260:Female; D045585:Flap Endonucleases; D016368:Frameshift Mutation; D019476:Insect Proteins / Q000235:genetics / Q000378:metabolism; D008297:Male; D008969:Molecular Sequence Data; D005810:Multigene Family; D009687:Nuclear Proteins; D011506:Proteins / Q000235:genetics*; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D014157:Transcription Factors; D020798:Two-Hybrid System Techniques; D000099250:DNA Excision Repair Protein ERCC-5
D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; D004706:Endodeoxyribonucleases; D004720:Endonucleases; D045585:Flap Endonucleases; D019476:Insect Proteins; D009687:Nuclear Proteins; D011506:Proteins; D014157:Transcription Factors; D000099250:DNA Excision Repair Protein ERCC-5; C097527:MEI-9 protein, Drosophila