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Cloning and expression of eukaryotic initiation factor 4B cDNA: sequence determination identifies a common RNA recognition motif.

S C Milburn·J W Hershey·M V Davies·K Kelleher·R J Kaufman
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Abstract

Eukaryotic protein synthesis initiation factor 4B (eIF-4B) is an 80,000 dalton polypeptide which is essential for the binding of mRNA to ribosomes. A highly purified preparation of eIF-4B from HeLa cells was subjected to enzymatic cleavage and amino-terminal amino acid sequence analysis. Degenerate oligonucleotide probes were used to isolate a 3851 bp cDNA encoding eIF-4B from a human cDNA library. The DNA encodes a protein comprising 611 residues with a mass of 69,843 daltons. The amino-terminal domain of eIF-4B contains a consensus RNA binding domain present in a number of other RNA binding proteins. Expression of eIF-4B in transfected COS-1 cells yielded a polypeptide which reacted with anti-eIF-4B antiserum and comigrated with purified eIF-4B. Expression of eIF-4B in COS-1 cells resulted in a general inhibition of translation, possibly due to a 50-fold eIF-4B overproduction.

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Amino Acid SequenceAnimalsBase SequenceBinding SitesCell LineCloning, MolecularEukaryotic Initiation FactorsGene ExpressionHeLa CellsHumansMolecular Sequence DataOligonucleotide ProbesPeptide FragmentsPeptide Initiation FactorsProtein ConformationRNA, MessengerSequence Homology, Nucleic AcidTransfectionComparative StudyJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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S C Milburn, J W Hershey, M V Davies, K Kelleher, R J Kaufman. 1990. Cloning and expression of eukaryotic initiation factor 4B cDNA: sequence determination identifies a common RNA recognition motif.. https://doi.org/10.1002/j.1460-2075.1990.tb07466.x

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