title: Complementation of the oxidatively damaged DNA repair defect in Cockayne syndrome A and B cells by Escherichia coli formamidopyrimidine DNA glycosylase.
abstract: Repair of the oxidized purine 8-oxo-7,8-dihydroguanine (8-oxoGua) is inefficient in cells belonging to the B complementation group of Cockayne syndrome (CS-B), a developmental and neurological disorder characterized by defective transcription-coupled repair. We show here that cells belonging to the A complementation group (CS-A) are also defective in repair of 8-oxoGua and we demonstrate that expression of the Escherichia coli formamidopyrimidine DNA glycosylase (FPG) completely corrects the repair deficiency in both CS-A and CS-B cells. Phenotypically, CS-A cells are normally sensitive to toxicity and micronuclei induced by the oxidizing agent potassium bromate. CS-B cells display sensitivity to elevated concentrations of potassium bromate but this is not compensated by FPG expression, suggesting toxicity of lesions that are not FPG substrates. The data indicate that 8-oxoGua is not a major toxic and clastogenic lesion in CS cells.
authors.affiliation: Experimental Oncology B Laboratory, Department of Translational Oncology, Istituto Nazionale Ricerca Cancro, Largo Rosanna Benzi n. 10, 16132 Genova, Italy.
authors.forename: Monica
authors.initials: M
authors.lastname: Ropolo
authors.forename: Paolo
authors.initials: P
authors.lastname: Degan
authors.forename: Mara
authors.initials: M
authors.lastname: Foresta
authors.forename: Mariarosaria
authors.initials: M
authors.lastname: D'Errico
authors.forename: Denise
authors.initials: D
authors.lastname: Lasigliè
authors.forename: Eugenia
authors.initials: E
authors.lastname: Dogliotti
authors.forename: Gianluigi
authors.initials: G
authors.lastname: Casartelli
authors.forename: Simonetta
authors.initials: S
authors.lastname: Zupo
authors.forename: Alessandro
authors.initials: A
authors.lastname: Poggi
authors.forename: Guido
authors.initials: G
authors.lastname: Frosina
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001959:Bromates / Q000494:pharmacology; D002273:Carcinogens / Q000494:pharmacology; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured / Q000187:drug effects; D003057:Cockayne Syndrome / Q000235:genetics*; D003114:Colony-Forming Units Assay; D004249:DNA Damage; D004260:DNA Repair; D043382:DNA-Formamidopyrimidine Glycosylase / Q000235:genetics / Q000378:metabolism*; D004926:Escherichia coli / Q000201:enzymology*; D005260:Female; D005347:Fibroblasts / Q000187:drug effects; D005816:Genetic Complementation Test; D005822:Genetic Vectors; D006801:Humans; D007668:Kidney / Q000378:metabolism / Q000473:pathology; D008297:Male; D015162:Micronucleus Tests; D014158:Transcription, Genetic; D001749:Urinary Bladder Neoplasms / Q000378:metabolism / Q000473:pathology
chemical_list: D001959:Bromates; D002273:Carcinogens; C019536:potassium bromate; D043382:DNA-Formamidopyrimidine Glycosylase