title: Relative repair of adenovirus damaged by sunlamp, UV and gamma-irradiation in Cockayne syndrome fibroblasts is different from that in xeroderma pigmentosum fibroblasts.
abstract: The DNA repair capacities of three unrelated Cockayne syndrome (CS) fibroblast strains were compared to that of three unrelated xeroderma pigmentosum (XP) strains for three different DNA damaging agents using a sensitive host cell reactivation (HCR) technique. Adenovirus type 2 (Ad 2) was treated with either UV light, gamma-rays or sunlamp-irradiation and subsequently assayed for its ability to form viral structural antigens (Vag) in the CS and XP strains using immunofluorescent straining. D37 values for the survival of Ad 2 Vag synthesis in the CS and XP strains, expressed as a percentage of those obtained in normal strains, were used as a measure of DNA repair capacity. Percent HCR values in the XP strains XP25RO, XP2BE and XP5BE respectively were lowest for UV (6, 14 and 6%), intermediate for sunlamp-irradiation (18, 32 and 10%) and highest for gamma-irradiation (65, 61 and 60%), whereas for the CS strains CS1BE, CS3BE and CS278CTO respectively, percent HCR values were lowest for UV (26, 30 and 34%), intermediate for gamma-irradiation (61, 64 and 69%) and near normal for sunlamp-irradiation (82, 73 and 89%). These results suggest that the 'spectrum of lesions' which is defectively repaired in CS is not the same as that which is defectively repaired in XP.
authors.forename: A J
authors.initials: AJ
authors.lastname: Rainbow
mesh_terms: D000260:Adenoviruses, Human / Q000378:metabolism / Q000528:radiation effects*; D002478:Cells, Cultured; D003057:Cockayne Syndrome / Q000378:metabolism*; D004249:DNA Damage; D004260:DNA Repair; D004392:Dwarfism / Q000378:metabolism*; D005347:Fibroblasts / Q000378:metabolism; D005455:Fluorescent Antibody Technique; D005720:Gamma Rays; D006801:Humans; D013472:Sunlight / Q000009:adverse effects*; D014466:Ultraviolet Rays / Q000009:adverse effects*; D014983:Xeroderma Pigmentosum / Q000378:metabolism*