Linked Life Data

8557663

Source:http://linkedlifedata.com/resource/pubmed/id/8557663

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1996-2-26
pubmed:abstractText
The eIF4 group initiation factors carry out recognition of the mRNA cap, unwinding of mRNA secondary structure, and binding of mRNA to the 43 S preinitiation complex. Infection by picornaviruses results in proteolytic cleavage of one of these factors, eIF4G, an event that severely restricts cap-dependent translation but permits cap-independent initiation to proceed from internal ribosome entry sequences in picornaviral RNAs. The 5'-untranslated region (5'-UTR) of eIF4G mRNA resembles such picornaviral sequences in being unusually long and containing multiple open reading frames and a polypyrimidine tract. When inserted upstream of a luciferase reporter gene, this 5'-UTR served as a translational enhancer in four different cell lines. Mutation of all four upstream ATG codons to AAG did not alter the translational enhancement. The presence of the eIF4G 5'-UTR between an RNA hairpin and the luciferase cistron stimulated expression 119-fold. Similarly, the presence of the 5'-UTR between the two cistrons of a bicistronic mRNA stimulated expression of the downstream cistron 42-fold. These results indicate that the eIF4G 5'-UTR directs internal initiation. The ability to continue synthesis of eIF4G when the cell is unable to carry out normal cap-dependent translation may represent an autoregulatory mechanism or be part of the cellular response to stresses that interrupt cap-dependent translation.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
12
pubmed:volume
271
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
623-6
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1996
pubmed:articleTitle
Internal initiation of translation directed by the 5'-untranslated region of the mRNA for eIF4G, a factor involved in the picornavirus-induced switch from cap-dependent to internal initiation.
pubmed:affiliation
Department of Biochemistry and Molecular Biology, Louisiana State University Medical Center, Shreveport 71130-3932, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.