title: Excision repair of UV-induced pyrimidine dimers in human skin in vivo.
abstract: The induction and loss of pyrimidine dimers in human skin in vivo was determined using UV endonuclease, alkaline sucrose sedimentations, and the fluorescent detection of nonradiolabeled DNA. The number of dimers induced following exposure of the skin to radiation emitted from a Burdick UV-800 sunlamp was quantitated by reacting the extracted DNA with Micrococcus luteus endonuclease specific for pyrimidine dimers. Exposure to 15 and 30 seconds of radiation emitted from this lamp produced the formation of 12.8 and 23.6 dimers per 10(8) daltons DNA, respectively. Approximately 50% of the dimers induced were lost 58 min after irradiation. Only a small percentage (less than 10) remained 24 hr postirradiation. These data partially characterize the process by which pyrimidine dimers are excised from human skin DNA in vivo.
mesh_terms: D000328:Adult; D002499:Centrifugation, Density Gradient; D004260:DNA Repair / Q000528:radiation effects*; D004720:Endonucleases / Q000378:metabolism; D005260:Female; D006801:Humans; D008297:Male; D011740:Pyrimidine Dimers / Q000378:metabolism / Q000528:radiation effects*; D012867:Skin / Q000378:metabolism* / Q000528:radiation effects; D014466:Ultraviolet Rays
chemical_list: D011740:Pyrimidine Dimers; D004720:Endonucleases