| Studies of the ethylation of rat liver transfer ribonucleic acid after administration of L-ethionine. | |
| | |
MedLine Citation:
|
PMID: 5085644 Owner: NLM Status: MEDLINE |
Abstract/OtherAbstract:
|
1. The ethylated nucleosides present in tRNA isolated from the livers of rats treated with 0.5g of l-ethionine/kg body wt. were investigated. Evidence that this tRNA contained N(2)-ethylguanine, N(2)N(2)-diethylguanine, N(2)-ethyl-N(2)-methylguanine, 7-ethylguanine, two ethylated pyrimidines and ethylated ribose groups was obtained. 2. Ethylation of bacterial tRNA was catalysed by extracts containing tRNA methylases prepared from rat liver by using S-adenosyl-l-ethionine as an ethyl donor, but the rate of ethylation was 20 times less than the rate of methylation with S-adenosyl-l-methionine as a methyl donor. 3. The principal product of such ethylation in vitro was N(2)-ethylguanine and traces of the other ethylated guanines and pyrimidines found in tRNA isolated from rats treated with ethionine in vivo were also found. 1-Ethyladenine was not formed, although 1-methyl-adenine is a major product of methylation of bacterial tRNA by these extracts, and 1-ethyladenine was not present in the rat liver tRNA isolated from ethionine-treated animals. 4. After injection of actinomycin D (15mg/kg body wt.) or l-methionine (1.0g/kg body wt.) before the ethionine, ethylation of tRNA was diminished by about 80% but not completely abolished. Administration of 1-aminocyclopentanecarboxylic acid (2.5g/kg body wt.) to inhibit the formation of S-adenosyl-l-ethionine inhibited ethylation of tRNA by 44%. 5. These results suggest that not all of the ethylation of tRNA that occurs in the livers of rats treated with ethionine is mediated by the action of tRNA methylases acting with S-adenosyl-l-ethionine as a substrate, but that this pathway does occur and accounts for a major part of the observed ethylation. 6. The results are discussed with reference to ethionine-induced hepatocarcinogenesis. |
| | |
Authors:
|
A E Pegg |
Related Documents
:
|
21236294 - Effects of the alpha- and gamma-polymorphs of glycine on the behavior of catalepsy pron... 6861754 - Exchange of histones h1 and h5 between chromatin fragments. a preference of h5 for high... 7276514 - Rex mutant in the norway rat. 1409104 - Morphological, immunohistochemical, stereological and nuclear shape characteristics of ... 1751524 - The influence of hypothyroidism on the transport of phosphate and on the lipid composit... 10727734 - Myelination in the splenium of the corpus callosum in adult male and female rats. |
Publication Detail:
|
Type: Journal Article |
Journal Detail:
|
Title: The Biochemical journal Volume: 128 ISSN: 0264-6021 ISO Abbreviation: Biochem. J. Publication Date: 1972 Jun |
Date Detail:
|
Created Date: 1973-01-16 Completed Date: 1973-01-16 Revised Date: 2010-09-13 |
Medline Journal Info:
|
Nlm Unique ID: 2984726R Medline TA: Biochem J Country: ENGLAND |
Other Details:
|
Languages: eng Pagination: 59-68 Citation Subset: IM |
Export Citation:
|
APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
|
Animals Carbon Isotopes Dactinomycin Ethionine / metabolism* Guanine / analysis Liver / metabolism* Liver Neoplasms / etiology Male Methionine Methylation Pyrimidines / analysis RNA, Bacterial / metabolism RNA, Transfer / metabolism* Rats Ribose / analysis |
| Chemical | |
Reg. No./Substance:
|
0/Carbon Isotopes; 0/Pyrimidines; 0/RNA, Bacterial; 13073-35-3/Ethionine; 50-69-1/Ribose; 50-76-0/Dactinomycin; 63-68-3/Methionine; 73-40-5/Guanine; 9014-25-9/RNA, Transfer |
| Comments/Corrections | |
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
Previous Document: 3-hydroxybutyrate dehydrogenase in tissues from normal and ketonaemic sheep.
Next Document: Lipoprotein lipase activity in the adipose tissue of rats adapted to controlled feeding schedules.