Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
7243
pubmed:dateCreated
2009-5-8
pubmed:abstractText
Translation elongation factors facilitate protein synthesis by the ribosome. Previous studies identified two universally conserved translation elongation factors, EF-Tu in bacteria (known as eEF1A in eukaryotes) and EF-G (eEF2), which deliver aminoacyl-tRNAs to the ribosome and promote ribosomal translocation, respectively. The factor eIF5A (encoded by HYP2 and ANB1 in Saccharomyces cerevisiae), the sole protein in eukaryotes and archaea to contain the unusual amino acid hypusine (N(epsilon)-(4-amino-2-hydroxybutyl)lysine), was originally identified based on its ability to stimulate the yield (endpoint) of methionyl-puromycin synthesis-a model assay for first peptide bond synthesis thought to report on certain aspects of translation initiation. Hypusine is required for eIF5A to associate with ribosomes and to stimulate methionyl-puromycin synthesis. Because eIF5A did not stimulate earlier steps of translation initiation, and depletion of eIF5A in yeast only modestly impaired protein synthesis, it was proposed that eIF5A function was limited to stimulating synthesis of the first peptide bond or that eIF5A functioned on only a subset of cellular messenger RNAs. However, the precise cellular role of eIF5A is unknown, and the protein has also been linked to mRNA decay, including the nonsense-mediated mRNA decay pathway, and to nucleocytoplasmic transport. Here we use molecular genetic and biochemical studies to show that eIF5A promotes translation elongation. Depletion or inactivation of eIF5A in the yeast S. cerevisiae resulted in the accumulation of polysomes and an increase in ribosomal transit times. Addition of recombinant eIF5A from yeast, but not a derivative lacking hypusine, enhanced the rate of tripeptide synthesis in vitro. Moreover, inactivation of eIF5A mimicked the effects of the eEF2 inhibitor sordarin, indicating that eIF5A might function together with eEF2 to promote ribosomal translocation. Because eIF5A is a structural homologue of the bacterial protein EF-P, we propose that eIF5A/EF-P is a universally conserved translation elongation factor.
pubmed:grant
pubmed:commentsCorrections
http://linkedlifedata.com/resource/pubmed/commentcorrection/19424157-10834843, http://linkedlifedata.com/resource/pubmed/commentcorrection/19424157-10987361, http://linkedlifedata.com/resource/pubmed/commentcorrection/19424157-1105576, http://linkedlifedata.com/resource/pubmed/commentcorrection/19424157-11448174, http://linkedlifedata.com/resource/pubmed/commentcorrection/19424157-12493761, http://linkedlifedata.com/resource/pubmed/commentcorrection/19424157-12869712, http://linkedlifedata.com/resource/pubmed/commentcorrection/19424157-15210970, http://linkedlifedata.com/resource/pubmed/commentcorrection/19424157-16214807, http://linkedlifedata.com/resource/pubmed/commentcorrection/19424157-16215987, http://linkedlifedata.com/resource/pubmed/commentcorrection/19424157-16449648, http://linkedlifedata.com/resource/pubmed/commentcorrection/19424157-16914118, http://linkedlifedata.com/resource/pubmed/commentcorrection/19424157-16987817, http://linkedlifedata.com/resource/pubmed/commentcorrection/19424157-17476569, http://linkedlifedata.com/resource/pubmed/commentcorrection/19424157-17578650, http://linkedlifedata.com/resource/pubmed/commentcorrection/19424157-17913637, http://linkedlifedata.com/resource/pubmed/commentcorrection/19424157-1850732, http://linkedlifedata.com/resource/pubmed/commentcorrection/19424157-18544041, http://linkedlifedata.com/resource/pubmed/commentcorrection/19424157-19424145, http://linkedlifedata.com/resource/pubmed/commentcorrection/19424157-5529301, http://linkedlifedata.com/resource/pubmed/commentcorrection/19424157-592398, http://linkedlifedata.com/resource/pubmed/commentcorrection/19424157-641056, http://linkedlifedata.com/resource/pubmed/commentcorrection/19424157-7419605, http://linkedlifedata.com/resource/pubmed/commentcorrection/19424157-776695, http://linkedlifedata.com/resource/pubmed/commentcorrection/19424157-8122109, http://linkedlifedata.com/resource/pubmed/commentcorrection/19424157-8253832, http://linkedlifedata.com/resource/pubmed/commentcorrection/19424157-8307948, http://linkedlifedata.com/resource/pubmed/commentcorrection/19424157-9056761, http://linkedlifedata.com/resource/pubmed/commentcorrection/19424157-9419357, http://linkedlifedata.com/resource/pubmed/commentcorrection/19424157-9582285, http://linkedlifedata.com/resource/pubmed/commentcorrection/19424157-965377
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
1476-4687
pubmed:author
pubmed:issnType
Electronic
pubmed:day
7
pubmed:volume
459
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
118-21
pubmed:dateRevised
2011-8-1
pubmed:meshHeading
pubmed:year
2009
pubmed:articleTitle
Hypusine-containing protein eIF5A promotes translation elongation.
pubmed:affiliation
Laboratory of Gene Regulation and Development, NICHD, National Institutes of Health, Bethesda, Maryland 20892, USA.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't, Research Support, N.I.H., Extramural, Research Support, N.I.H., Intramural