title: The induction and repair of lesions produced by the photolysis of (6-4) photoproducts in normal and UV-hypersensitive human cells.
abstract: A radioimmunoassay was used to study the induction and repair of damage produced by the photolysis of (6-4) photoproducts in normal and UV-sensitive human cells. Photochemical conditions were established to optimize the production of photolyzed (6-4) photoproducts in human cell DNA with minimal induction of other photoproducts. The repair of this photoproduct, presumed to be a Dewar pyrimidinone, was similar to that determined for the (6-4) photoproduct, with most of the antibody-binding sites removed within 4 h post-photolysis. Whereas xeroderma pigmentosum group A cells were deficient in the repair of this lesion, an XP variant and two cell lines selectively hypersensitive to UVB-irradiation were shown to have normal repair. The radioimmunoassay was further used to demonstrate the alkali-lability of the (6-4) photolysis product.
authors.affiliation: University of Texas System Cancer Center, Smithville 78957.
authors.forename: D L
authors.initials: DL
authors.lastname: Mitchell
mesh_terms: D004260:DNA Repair; D006801:Humans; D066298:In Vitro Techniques; D009993:Osmium Tetroxide; D010782:Photolysis; D011740:Pyrimidine Dimers / Q000378:metabolism*; D011863:Radioimmunoassay; D013057:Spectrum Analysis; D014466:Ultraviolet Rays
chemical_list: D011740:Pyrimidine Dimers; D009993:Osmium Tetroxide