title: Identification of DNA sequence responsible for 5-bromodeoxyuridine-induced gene amplification.
abstract: Bromodeoxyuridine (BrdUrd) treatment of the prolactin nonproducing subclone of GH cells (rat pituitary tumor cells) induces amplification of a 20-kilobase DNA fragment including all of the prolactin gene coding sequences. This amplified DNA segment, which is flanked by two unamplified regions, thus designates a unit of BrdUrd-induced amplified sequence. Cloned DNA segments, 10.3 kilobases long, from the 5' end of the rat prolactin gene of BrdUrd-responsive and -nonresponsive cells, were ligated to the thymidine kinase gene of herpes simplex virus type 1 (HSV1TK), and the hybrid DNA was transferred to thymidine kinase-deficient mouse fibroblast cells by transfection. The HSV1TK gene and the rat prolactin gene were amplified together in drug-treated transfectants carrying the hybrid DNA HSV1TK gene and rat prolactin gene of BrdUrd-responsive GH cells. These results suggest that the 10.3-kilobase DNA segment at the 5' end of the rat prolactin gene of BrdUrd-responsive GH cells carries the information for drug-induced gene amplification (amplicon) and that another gene, such as the HSV1TK gene, is also amplified when the latter is placed adjacent to this segment.
mesh_terms: D000818:Animals; D001483:Base Sequence; D001973:Bromodeoxyuridine / Q000494:pharmacology*; D002460:Cell Line; D003001:Cloning, Molecular; D004247:DNA / Q000235:genetics*; D004274:DNA, Recombinant; D005784:Gene Amplification; D005814:Genes, Viral; D051379:Mice; D011388:Prolactin / Q000235:genetics; D051381:Rats; D018139:Simplexvirus / Q000235:genetics; D013937:Thymidine Kinase / Q000235:genetics; D014162:Transfection
chemical_list: D004274:DNA, Recombinant; D011388:Prolactin; D004247:DNA; D013937:Thymidine Kinase; D001973:Bromodeoxyuridine