title: DNA replication and repair in a human melanoma cell-line resistant to ultra-violet-radiation.
abstract: The effect of ultra-violet (U.V.)-irradiation on DNA replication was studied in a U.V.-resistant, human melanoma cell-line (MM96). Semi-conservative synthesis of DNA was decreased about five-fold by a U.V.-dose of 100 ergs/mm2. The size of DNA fragments synthesized in irradiated cells at short times after U.V. was smaller than those synthesized in unirradiated cells. Elongation of these fragments occurred with time, and 6 hours after irradiation cells synthesized DNA in fragments of the same size as obtained in unirradiated cells. In this post-replication repair process, elongation appeared to involve de novo synthesis and was not inhibited by theophylline.
mesh_terms: D002460:Cell Line; D004260:DNA Repair / Q000187:drug effects / Q000528:radiation effects*; D004261:DNA Replication / Q000187:drug effects / Q000528:radiation effects*; D013806:Theophylline / Q000494:pharmacology; D014466:Ultraviolet Rays
chemical_list: D013806:Theophylline