Photoreactivation of cyclobutane dimers and (6-4) photoproducts in the epidermis of the marsupial, Monodelphis domestica.
Radioimmunoassays were used to investigate the repair of cyclobutane pyrimidine dimers and pyrimidine (6-4)pyrimidone photoproducts ((6-4] photoproducts) in the epidermis of the South American opossum, Monodelphis domestica. In the absence of photoreactivating light, both types of photodamage were excised with similar kinetics, 50% of the damage remaining 8 h after UV irradiation in vivo. Exposure of UV-irradiated skin to photoreactivating light resulted in removal of most of the cyclobutane dimers and an enhanced rate of (6-4) photoproduct repair. Photoenhanced excision repair of non-dimer damage increases the range of biologically effective lesions removed by in vivo photoreactivation.
Mitchell
D L
DL
Department of Experimental Carcinogenesis, University of Texas, M.D. Anderson Cancer Center, Smithville 78957.
Applegate
L A
LA
Nairn
R S
RS
Ley
R D
RD
D000818:Animals; D004247:DNA / Q000302:isolation & purification / Q000528:radiation effects; D004249:DNA Damage; D004260:DNA Repair; D008027:Light; D009893:Opossums; D011740:Pyrimidine Dimers / Q000528:radiation effects*; D012867:Skin / Q000528:radiation effects*; D014466:Ultraviolet Rays
D011740:Pyrimidine Dimers; D004247:DNA