Switch to
Predicate | Object |
---|---|
rdf:type | |
lifeskim:mentions | |
pubmed:issue |
1
|
pubmed:dateCreated |
1980-7-22
|
pubmed:abstractText |
Poly(uridylic acid) [poly(U)] and poly(xanthidylic acid) [poly(X)] strongly stimulate the IF-2-dependent binding of fMET-tRNA to 30-S ribosomal subunits from Escherichia coli [Van der Laken et al. (1979) FEBS Lett. 100, 230-234]. The N-formylmethionine moiety is incorporated into poly(phenylalanine) upon subsequent addition of other components required for protein synthesis when poly(U) is used as template. This paper shows that N-acetylated Phe-tRNAPhe (AcPhe-tRNA), but not Phe-tRNAPhe or tRNAPhe, competes with fMET-tRNA for binding to poly(U)-programmed 30-S ribosomal subunits. The two species of N-blocked aminoacyl-tRNA are bound to poly(U)-programmed and poly(X)-programmed 30-S subunits in a ratio that is linearly dependent on the ratio of the two species added. With poly(U) as template there is no apparent preference for either fMET-tRNA or AcPhe-tRNA, whereas with poly(X) there is a 2-3-fold preference for fMET-tRNA. The initiation factor IF-2, which is strictly required for the binding of N-blocked aminoacyl-tRNAs, has a higher affinity for fMET-tRNA than for AcPhe-tRNA. It is concluded that (a) interaction of the 30-S ribosomal subunit with poly(U) or poly(X) leads to IF-2-dependent binding of N-blocked aminoacyl-tRNA; (b) the initiation factor IF-2-discriminates in favour of fMET-TRNA; (c) the presence of the cognate codon discriminates in favour of the corresponding N-blocked aminoacyl-tRNA.
|
pubmed:language |
eng
|
pubmed:journal | |
pubmed:citationSubset |
IM
|
pubmed:chemical |
http://linkedlifedata.com/resource/pubmed/chemical/Codon,
http://linkedlifedata.com/resource/pubmed/chemical/Eukaryotic Initiation Factor-2,
http://linkedlifedata.com/resource/pubmed/chemical/Peptide Initiation Factors,
http://linkedlifedata.com/resource/pubmed/chemical/Polyribonucleotides,
http://linkedlifedata.com/resource/pubmed/chemical/Proteins,
http://linkedlifedata.com/resource/pubmed/chemical/RNA, Messenger,
http://linkedlifedata.com/resource/pubmed/chemical/RNA, Transfer, Amino Acyl
|
pubmed:status |
MEDLINE
|
pubmed:month |
Feb
|
pubmed:issn |
0014-2956
|
pubmed:author | |
pubmed:issnType |
Print
|
pubmed:volume |
104
|
pubmed:owner |
NLM
|
pubmed:authorsComplete |
Y
|
pubmed:pagination |
19-33
|
pubmed:dateRevised |
2007-7-23
|
pubmed:meshHeading |
pubmed-meshheading:6989597-Codon,
pubmed-meshheading:6989597-Escherichia coli,
pubmed-meshheading:6989597-Eukaryotic Initiation Factor-2,
pubmed-meshheading:6989597-Kinetics,
pubmed-meshheading:6989597-Peptide Initiation Factors,
pubmed-meshheading:6989597-Polyribonucleotides,
pubmed-meshheading:6989597-Proteins,
pubmed-meshheading:6989597-RNA, Messenger,
pubmed-meshheading:6989597-RNA, Transfer, Amino Acyl,
pubmed-meshheading:6989597-Ribosomes,
pubmed-meshheading:6989597-Structure-Activity Relationship
|
pubmed:year |
1980
|
pubmed:articleTitle |
The role of the codon and the initiation factor IF-2 in the selection of N-blocked aminoacyl-tRNA for initiation.
|
pubmed:publicationType |
Journal Article
|