Switch to
| Predicate | Object |
|---|---|
| rdf:type | |
| lifeskim:mentions | |
| pubmed:issue |
1
|
| pubmed:dateCreated |
1978-12-20
|
| pubmed:abstractText |
The formation of 30-S initiation complexes depends strongly on initiation factor IF-3; at molar ratios of IF-3 to 30-S ribosomes up to one a stimulation is observed, whereas at ratios higher than one, initiation complex formation declines strongly. The target of the observed inhibition of fMet-tRNA binding at high concentrations of IF-3 is the 30-S initiation complex itself. On the one hand addition of IF-3 to preformed 30-S initiation complexes leads to a release of bound fMet-tRNA which is linear with the amount of factor added, whereas no effect on isolated 70-S initiation complexes is seen. The release of fMet-tRNA from preformed 30-S initiation complexes is accompanied by a release of IF-2 in a one-to-one molar ratio which is in agreement with our previous findings showing that binding of fMet-tRNA takes place via a binary complex: IF-2 . fMet-tRNA (Eur. J. Biochem. 66, 181--192 and 77, 69--75). On the other hand increasing amounts of both IF-2 and fMet-tRNA relieve the IF-3-induced inhibition of 30-S initiation complex formation. From these findings it is concluded that IF-3 and the IF-2 . fMet-tRNA complex are mutually exclusive on the 30-S ribosome. This implies that under our experimental conditions MS2 RNA binding precedes fMet-tRNA binding if one accepts that the presence of IF-3 on the 30-S subunit is obligatory for messenger binding.
|
| pubmed:language |
eng
|
| pubmed:journal | |
| pubmed:citationSubset |
IM
|
| pubmed:chemical | |
| pubmed:status |
MEDLINE
|
| pubmed:month |
Aug
|
| pubmed:issn |
0014-2956
|
| pubmed:author | |
| pubmed:issnType |
Print
|
| pubmed:day |
15
|
| pubmed:volume |
89
|
| pubmed:owner |
NLM
|
| pubmed:authorsComplete |
Y
|
| pubmed:pagination |
213-20
|
| pubmed:dateRevised |
2007-7-23
|
| pubmed:meshHeading |
pubmed-meshheading:359327-Escherichia coli,
pubmed-meshheading:359327-Kinetics,
pubmed-meshheading:359327-Methionine,
pubmed-meshheading:359327-N-Formylmethionine,
pubmed-meshheading:359327-Peptide Initiation Factors,
pubmed-meshheading:359327-Protein Binding,
pubmed-meshheading:359327-RNA, Transfer,
pubmed-meshheading:359327-Ribosomes
|
| pubmed:year |
1978
|
| pubmed:articleTitle |
Initiation factor IF-3 and the binary complex between initiation factor IF-2 and formylmethionyl-tRNA are mutually exclusive on the 30-S ribosomal subunit.
|
| pubmed:publicationType |
Journal Article
|