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

EMBO J. 1990 Sep;9(9):2783-90. doi: 10.1002/j.1460-2075.1990.tb07466.x.

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.

Publication types

  • Comparative Study
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • Binding Sites
  • Cell Line
  • Cloning, Molecular
  • Eukaryotic Initiation Factors*
  • Gene Expression
  • HeLa Cells / metabolism
  • Humans
  • Molecular Sequence Data
  • Oligonucleotide Probes
  • Peptide Fragments / isolation & purification
  • Peptide Initiation Factors / genetics*
  • Protein Conformation
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • Sequence Homology, Nucleic Acid
  • Transfection

Substances

  • Eukaryotic Initiation Factors
  • Oligonucleotide Probes
  • Peptide Fragments
  • Peptide Initiation Factors
  • RNA, Messenger
  • eIF-4B