Ryu, JC Youn, JY Kim, YJ Kwon, OS Song, YS Kim, HT Cho, KH Chang, IM 2024-01-21T15:06:24Z 2024-01-21T15:06:24Z 2022-01-10 1999-09 1383-5718 https://pubs.kist.re.kr/handle/201004/141947 This paper describes the spectrum of mutations induced by 4-nitroquinoline N-oxide (4-NQO) in the lad target gene of the transgenic Big Blue(R) Rat2 cell line. There are only a few report for the mutational spectrum of 4-NQO in a mammalian system although its biological and genetic effects have been well studied. Big Blue(R) Rat2 cells were treated with 0.03125, 0.0625 or 0.125 mu g/ml of 4-NQO, the highest concentration giving 85% survival. Our results indicated that the mutant frequency (MF) induced by 4-NQO was dose-dependent with increases from three- to seven-fold. The DNA sequence analysis of lad mutants from the control and 4-NQO treatment groups revealed an obvious difference in the spectra of mutations. In spontaneous mutants, transition (60%) mutations, especially G:C --> A:T transition (45%), were most frequent. However, the major type of base substitution after treatment of 4-NQO was transversions (68.8%), especially G:C --> T:A (43.8%), while only 25% of mutants were transitions. These results are consistent with those produced by 4-NQO in other systems and the transgenic assay system will be a powerful tool to postulate more accurately the mechanism of chemical carcinogenesis involved. (C) 1999 Elsevier Science B.V, All rights reserved. English ELSEVIER SCIENCE BV Mutation spectrum of 4-nitroquinoline N-oxide in the lacI transgenic Big Blue((R)) Rat2 cell line Article 10.1016/S1383-5718(99)00136-9 1 MUTATION RESEARCH-GENETIC TOXICOLOGY AND ENVIRONMENTAL MUTAGENESIS, v.445, no.1, pp.127 - 135 MUTATION RESEARCH-GENETIC TOXICOLOGY AND ENVIRONMENTAL MUTAGENESIS 445 1 127 135 N scie scopus 000082839400012 2-s2.0-0032829015 Biotechnology & Applied Microbiology Genetics & Heredity Toxicology Biotechnology & Applied Microbiology Genetics & Heredity Toxicology Article SHUTTLE VECTORS COLORIMETRIC ASSAY ESCHERICHIA-COLI MAMMALIAN-CELLS BLUE(R) RAT2 P53 GENE DNA MICE EFFICIENT 1-OXIDE 4-nitroquinoline N-oxide Big Blue((R)) Rat2 cell line lacI gene mutational spectrum