Linked Life Data

16519677

Source:http://linkedlifedata.com/resource/pubmed/id/16519677

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
2006-3-7
pubmed:abstractText
Eukaryotic translation initiation factor 5A (eIF5A) is the only cellular protein that contains the unusual amino acid hypusine [N(epsilon)-(4-amino-2-hydroxybutyl)lysine]. Vertebrates carry two genes that encode two eIF5A isoforms, eIF5A-1 and eIF5A-2, which, in humans, are 84% identical. eIF5A-1 mRNA (1.3 kb) and protein (18 kDa) are constitutively expressed in human cells. In contrast, expression of eIF5A-2 mRNA (0.7-5.6 kb) and eIF5A-2 protein (20 kDa) varies widely. Whereas eIF5A-2 mRNA was demonstrable in most cells, eIF5A-2 protein was detectable only in the colorectal and ovarian cancer-derived cell lines SW-480 and UACC-1598, which showed high overexpression of eIF5A-2 mRNA. Multiple forms of eIF5A-2 mRNA (5.6, 3.8, 1.6 and 0.7 kb) were identified as the products of one gene with various lengths of 3'-UTR, resulting from the use of different polyadenylation (AAUAAA) signals. The eIF5A-1 and eIF5A-2 precursor proteins were modified comparably in UACC-1598 cells and both were similarly stable. When eIF5A-1 and eIF5A-2 coding sequences were expressed from mammalian vectors in 293T cells, eIF5A-2 precursor was synthesized at a level comparable to that of eIF5A-1 precursor, indicating that the elements causing inefficient translation of eIF5A-2 mRNA reside outside of the open reading frame. On sucrose gradient separation of cytoplasmic RNA, only a small portion of total eIF5A-2 mRNA was associated with the polysomal fraction, compared with a much larger portion of eIF5A-1 mRNA in the polysomes. These findings suggest that the failure to detect eIF5A-2 protein even in eIF5A-2 mRNA positive cells is, at least in part, due to inefficient translation.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
1742-464X
pubmed:author
pubmed:issnType
Print
pubmed:volume
273
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1102-14
pubmed:dateRevised
2009-7-24
pubmed:meshHeading
pubmed-meshheading:16519677-Base Sequence, pubmed-meshheading:16519677-Cell Line, pubmed-meshheading:16519677-Cell Line, Tumor, pubmed-meshheading:16519677-Humans, pubmed-meshheading:16519677-Lysine, pubmed-meshheading:16519677-Molecular Sequence Data, pubmed-meshheading:16519677-Neoplasms, pubmed-meshheading:16519677-Oxidoreductases Acting on CH-NH Group Donors, pubmed-meshheading:16519677-Peptide Initiation Factors, pubmed-meshheading:16519677-Polyadenylation, pubmed-meshheading:16519677-Polyribosomes, pubmed-meshheading:16519677-Protein Biosynthesis, pubmed-meshheading:16519677-Protein Isoforms, pubmed-meshheading:16519677-Protein Precursors, pubmed-meshheading:16519677-Protein Processing, Post-Translational, pubmed-meshheading:16519677-RNA, Messenger, pubmed-meshheading:16519677-RNA-Binding Proteins, pubmed-meshheading:16519677-Transfection
pubmed:year
2006
pubmed:articleTitle
Differential expression of eIF5A-1 and eIF5A-2 in human cancer cells.
pubmed:affiliation
Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD 20892-4340, USA.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't, Research Support, N.I.H., Intramural