Linked Life Data

10501483

Source:http://linkedlifedata.com/resource/pubmed/id/10501483

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:dateCreated
1999-10-7
pubmed:abstractText
Translation initiation of poliovirus and hepatitis C virus (HCV) RNA occurs by entry of ribosomes to the internal RNA sequence, called the internal ribosomal entry site (IRES). Both IRES bind to the La protein and are thought to require the protein for their translation initiation activity, although they are greatly different in both the primary and predicted secondary structures. To compare the La protein requirement for these IRES, we took advantage of I-RNA from the yeast Saccharomyces cerevisiae, which has been reported to bind to La protein and block poliovirus IRES-mediated translation initiation. In a cell-free translation system prepared from HeLa cells, yeast I-RNA inhibited translation initiation on poliovirus RNA as expected, but did not significantly inhibit translation initiation on HCV RNA. However, the translation initiation directed by either IRES was apparently inhibited by I-RNA in rabbit reticulocyte lysates, in which La protein is limiting. I-RNA-mediated inhibition of HCV IRES-dependent translation in rabbit reticulocyte lysates was reversed by exogenous addition of purified recombinant La protein of smaller amounts than necessary to reverse poliovirus IRES-dependent translation. These results suggest that HCV IRES requires lower concentrations of La protein for its function than does poliovirus IRES. Immunofluorescence studies showed that HCV infection appeared not to affect the subcellular localization of La protein, which exists mainly in the nucleus, although La protein redistributed to the cytoplasm after poliovirus infection. The data are compatible with the low requirement of La protein for HCV IRES activity.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0022-1317
pubmed:author
pubmed:issnType
Print
pubmed:volume
80 ( Pt 9)
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2319-27
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1999
pubmed:articleTitle
Lower concentration of La protein required for internal ribosome entry on hepatitis C virus RNA than on poliovirus RNA.
pubmed:affiliation
Department of Microbiology, Institute of Medical Science, The University of Tokyo, Japan.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't