Characterization of initiation factor eIF-3 from wheat germ.

J W Checkley; L Cooley; J M Ravel

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PubMed · 6906354

Characterization of initiation factor eIF-3 from wheat germ.

J W Checkley·L Cooley·J M Ravel

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Abstract

Initiation factor eIF-3 has been isolated from the 120 mM KCl postribosomal supernatant of wheat germ by chromatography on DEAE-cellulose and phosphocellulose. Glycerol gradient centrifugation and polyacrylamide gel electrophoresis under nondenaturing conditions indicate that the eIF-3 prepared in this manner is at least 85% pure. Polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate shows that the wheat germ eIF-3 contains 11 polypeptides, ranging in molecular weight from about 25,000 to 120,000. Eight of the polypeptides are present in equimolar amounts; two of the polypeptides are present at molar ratios of about 0.5; and one is present at a molar ratio of about 0.3. The highly purified wheat germ eIF-3 does not prevent the association of wheat germ 40S and 60 S ribosomal subunits to a significant extent. Wheat germ eIF-3 does not increase appreciably the ability of eIF-2 to form a ternary complex with Met-tRNAf and GTP. It does, however, enhance the binding of Met-tRNAf to 40 S ribosomal subunits in the presence of eIF-2 and GTP.

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Eukaryotic Initiation Factor-3 Kinetics Macromolecular Substances Magnesium Molecular Weight Peptide Initiation Factors Plants Protein Biosynthesis RNA, Transfer, Amino Acyl RNA, Transfer, Met Ribosomes Triticum Journal Article Research Support, U.S. Gov't, P.H.S.

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J W Checkley, L Cooley, J M Ravel. 1981-02-25. Characterization of initiation factor eIF-3 from wheat germ.. https://pubmed.ncbi.nlm.nih.gov/6906354/

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