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标题：Modification of DNA by aflatoxin B1 creates alkali-labile lesions in DNA at positions of guanine and adenine
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作者：A D D'Andrea ; W A Haseltine
期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1978
卷号：75
期号：9
页码：4120-4124
DOI：10.1073/pnas.75.9.4120
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：The damage to DNA by the hepatocarcinogen aflatoxin B1 was investigated. A DNA fragment of known sequence of the lactose promoter-operator region was used as a substrate for modification by aflatoxin B1. The DNA was incubated with aflatoxin B1 in crude mammalian liver extracts or with purified microsomes. Treatment of the DNA incubated in the complete system with either 1 M piperidine or 0.1 M NaOH at 90 degrees revealed alkali-labile lesions in the DNA. The exact location of the cleavage site was determined by comparison of the length of the cleavage products with the known sequence on polyacrylamide gels. The lengths of the cleavage products were the same as those produced by alkali-induced breakage of the same sequence of DNA that had been modified with dimethyl sulfate. The major cleavage products of the aflatoxin B1-modified DNA were at positions of guanine and the minor cleavage products were at positions of adenine. These studies show that modification of DNA by aflatoxin B1 creates alkali-labile sites at positions of guanine and, to a lesser extent, adenine.