M. Bignami , A. Vitelli , A. Di Muccio , M. Terlizzese , A. Calcagnile , G.A. Zapponi , P.H.M. Lohman , L. den Engelse , E. Dogliotti
{"title":"Relationship between specific alkylated bases and mutations at two gene loci induced by ethylnitrosourea and diethyl sulfate in CHO cells","authors":"M. Bignami , A. Vitelli , A. Di Muccio , M. Terlizzese , A. Calcagnile , G.A. Zapponi , P.H.M. Lohman , L. den Engelse , E. Dogliotti","doi":"10.1016/0167-8817(88)90006-5","DOIUrl":null,"url":null,"abstract":"<div><p>DNA adduct formation and induction of mutations at gene loci, hypoxanthine-guanine-phosphoribosyltranferase (HPRT) and Na,K-ATPase, were determined simultaneously in Chinese hamster ovary (CHO) cells after treatment with 2 ethylating agents, ethylnitrosourea (ENU) or diethyl sulfate (DES). Doses of DES and ENU, which resulted in equal levels of <em>O</em><sup>6</sup>-ethylguanine (O<sup>6</sup>-EtGua) and <em>O</em><sup>6</sup>-ethylthymine (O<sup>4</sup>-EtThy) in the DNA, were found to induce very similar frequencies of 6-thioguanine-resistant (6-TG<sup>r</sup>) mutants. Formation of these DNA adducts might therefore be correlated with mutations induced at the HPRT locus.</p><p>When, however, the same analysis was applied to ouabain-resistant (our<sup>r</sup>) mutants, it was found that, at similar levels of O<sup>6</sup>-EtGua and O<sup>4</sup>-EtThy, DES induced many more oua<sup>r</sup> mutants than ENU. This result supports the notion that primary DNA lesions other than O<sup>6</sup>-EtGua and O<sup>4</sup>-EtThy are involved in the fixation of ENU- and DES-induced mutations at the Na,K-ATPase gene locus.</p></div>","PeriodicalId":100936,"journal":{"name":"Mutation Research/DNA Repair Reports","volume":null,"pages":null},"PeriodicalIF":0.0000,"publicationDate":"1988-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0167-8817(88)90006-5","citationCount":"16","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Mutation Research/DNA Repair Reports","FirstCategoryId":"1085","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/0167881788900065","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 16
Abstract
DNA adduct formation and induction of mutations at gene loci, hypoxanthine-guanine-phosphoribosyltranferase (HPRT) and Na,K-ATPase, were determined simultaneously in Chinese hamster ovary (CHO) cells after treatment with 2 ethylating agents, ethylnitrosourea (ENU) or diethyl sulfate (DES). Doses of DES and ENU, which resulted in equal levels of O6-ethylguanine (O6-EtGua) and O6-ethylthymine (O4-EtThy) in the DNA, were found to induce very similar frequencies of 6-thioguanine-resistant (6-TGr) mutants. Formation of these DNA adducts might therefore be correlated with mutations induced at the HPRT locus.
When, however, the same analysis was applied to ouabain-resistant (ourr) mutants, it was found that, at similar levels of O6-EtGua and O4-EtThy, DES induced many more ouar mutants than ENU. This result supports the notion that primary DNA lesions other than O6-EtGua and O4-EtThy are involved in the fixation of ENU- and DES-induced mutations at the Na,K-ATPase gene locus.