Linked Life Data

8286391

Source:http://linkedlifedata.com/resource/pubmed/id/8286391

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1994-2-18
pubmed:abstractText
Selenocysteine is cotranslationally introduced into a growing polypeptide in response to certain UGA codons in selenoprotein mRNAs. The biosynthesis of this amino acid initiates by aminoacylation of specific tRNAs (designated tRNA([Ser]Sec)) with serine and subsequent conversion of the serine moiety to selenocysteine. The resulting selenocysteyl-tRNA then donates selenocysteine to protein. In most higher vertebrate cells and tissues examined, multiple selenocysteine isoacceptors have been described. Two of these have been determined to differ by only a single modified residue in the wobble position of the anticodon. In addition, the steady-state levels and relative distributions of these isoacceptors have been shown to be influenced by the presence of selenium. In order to gain a better understanding of the relationship between these tRNAs and how they are regulated, both the Xenopus selenocysteine tRNA gene and an in vitro synthesized RNA have each been injected into Xenopus oocytes and their maturation analyzed. In this system, selenium enhanced RNA stability and altered the distribution of isoacceptors that differ by a single ribose methylation. Interestingly, the biosynthesis of one of these modified nucleosides (5-methylcarboxymethyl-2'-O-methyluridine), which has been identified only in the wobble position of selenocysteine tRNA, also occurs in oocytes. Examination of the modified residues in both the naturally occurring Xenopus selenocysteine tRNA and the products generated from exogenous templates in oocytes demonstrated the faithful reconstruction of the biosynthetic pathway for these tRNAs.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
18
pubmed:volume
33
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
601-5
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1994
pubmed:articleTitle
Reconstitution of the biosynthetic pathway of selenocysteine tRNAs in Xenopus oocytes.
pubmed:affiliation
Laboratory of Experimental Carcinogenesis, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.