Linked Life Data

884680

Source:http://linkedlifedata.com/resource/pubmed/id/884680

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
9
pubmed:dateCreated
1977-9-29
pubmed:abstractText
Cancer patients and tumor-bearing animals excrete high levels of modified purines and pyrimidines some of which, e.g., N2,N2-dimethylguanosine, can originate only from transfer RNA (tRNA). Until recently, it could not be ascertained whether the high level of excretion of such compounds is due to cell death or specific tRNA turnover. However, an approach to this problem became feasible, with beta-aminoisobutyric acid as a probe. This compound is a terminal degradation product of thymine which is present in both DNA and tRNA. Since the pathway of synthesis of thymine is different in the two macromolecules, it and its end product, beta-aminoisobutyric acid can be differentially labeled with [14C]formate and [3H3]methylmethionine as precursors. Therefore the ratio of the two labels in the excreted beta-aminoisobutyric acid is a measure of the macromolecular origin of the degradation product. We have found from such analysis that tRNA's are not homogeneous in their turnover rate. There is a subpopulation that turns over much faster than the rest. The turnover rate of a subpopulation of tRNA's in tumor tissue exceeds the turnover rate of tRNA's in normal tissue. Such rapid degradation of tRNA's must be the source of the massive excretion of modified nucleosides by cancer patients which can be 10-fold higher than in normal subjects.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0008-5472
pubmed:author
pubmed:issnType
Print
pubmed:volume
37
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
3362-6
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1977
pubmed:articleTitle
High turnover rate of transfer RNA in tumor tissue.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.