Evidence for ethylation of rat liver deoxyribonucleic acid after administration of ethionine.
1. Administration of a large dose (500mg/kg body wt.) of (3)H-labelled l-ethionine to rats resulted in the incorporation of a small amount of radioactivity into the liver DNA. Considerable evidence that this radioactivity was not due to contamination of the isolated DNA with labelled protein, RNA, S-adenosyl-l-ethionine or l-ethionine was obtained. 2. After acidic hydrolysis of the DNA isolated from the livers of rats treated with labelled l-ethionine, virtually all of the radioactivity present in the DNA was found in a fraction with similar chromatographic properties to 7-ethylguanine. 3. Treatment of rats with comparable doses of l-methionine did not lead to the formation of 7-methylguanine in the liver DNA. 4. These results are discussed in relation to the induction of liver tumours by ethionine.
D000478:Alkylation; D000818:Animals; D002273:Carcinogens; D002852:Chromatography, Ion Exchange; D004247:DNA / Q000032:analysis / Q000378:metabolism*; D005001:Ethionine / Q000378:metabolism*; D006147:Guanine / Q000032:analysis; D006868:Hydrolysis; D008099:Liver / Q000378:metabolism*; D008113:Liver Neoplasms / Q000139:chemically induced; D008297:Male; D008715:Methionine / Q000378:metabolism; D051381:Rats; D014316:Tritium
D002273:Carcinogens; D014316:Tritium; D006147:Guanine; D004247:DNA; D008715:Methionine; D005001:Ethionine