Mode of action of the heme-controlled translational inhibitor: relationship of eukaryotic initiation factor 2-stimulating protein to translation restoring factor.
- 1 January 1981
- journal article
- research article
- Published by Proceedings of the National Academy of Sciences in Proceedings of the National Academy of Sciences
- Vol. 78 (1) , 220-223
- https://doi.org/10.1073/pnas.78.1.220
Abstract
The translation restoring factor (RF) and the eukaryotic initiation factor 2 (eIF-2) stimulating protein (ESP) were purified to near homogeneity from the postribosomal supernatant and the ribosomal salt wash, respectively, of rabbit reticulocyte lysate. They were isolated in the form of eIF-2 complexes, apparently in a 1:1 ratio. Their virtually identical sodium dodecyl sulfate/polyacrylamide gel electrophoretic patterns show, in addition to the eIF-2 .alpha.(38,000), .beta.(52,000) and .gamma.(54,000) bands, peptide bands at .apprx. 80, 65, 57, 40 and 32 kilodaltons. The apparent MW of either complex is .apprx. 450,000, whereas that of free translation restoring factor (RF) is .apprx. 250,000. At 0.5 mM Mg2+, both ESP and RF stimulate ternary complex (eIF-2.cntdot.GTP.cntdot.Met-tRNAi) formation catalytically with unphosphorylated eIF-2. Phosphorylation of the eIF-2 .alpha. subunit by preincubation with eIF-2 .alpha. kinase and ATP, which virtually blocks eIF-2-ESP interaction, results in only partial blocking of the interaction with RF. This may explain the translation-restoring activity of RF.This publication has 16 references indexed in Scilit:
- Purification and properties of the double-stranded RNA-activated eukaryotic initiation factor 3 kinase from rabbit reticulocytes.Proceedings of the National Academy of Sciences, 1980
- Further studies on the mode of action of the heme-controlled translational inhibitor: stimulating protein acts at level of binary complex formation.Proceedings of the National Academy of Sciences, 1979
- Further studies on the mode of action of the heme-controlled translational inhibitor.Proceedings of the National Academy of Sciences, 1979
- Regulation of protein synthesis in rabbit reticulocyte lysates: Additional initiation factor required for formation of ternary complex (eIF-2·GTP·Met-tRNA f ) and demonstration of inhibitory effect of heme-regulated protein kinaseProceedings of the National Academy of Sciences, 1979
- Regulation of protein synthesis in rabbit reticulocyte lysates: purification and characterization of heme-reversible translational inhibitor.Proceedings of the National Academy of Sciences, 1978
- Mode of action of the hemin-controlled inhibitor of protein synthesis: studies with factors from rabbit reticulocytes.Proceedings of the National Academy of Sciences, 1978
- Mode of action of the hemin-controlled inhibitor of protein synthesis.Proceedings of the National Academy of Sciences, 1978
- Purification and characterization of initiation factor IF-E2 from rabbit reticulocytes.Journal of Biological Chemistry, 1976
- Control of protein synthesis by hemin. Isolation and characterization of a supernatant factor from rabbit reticulocyte lysateBiochimica et Biophysica Acta (BBA) - Nucleic Acids and Protein Synthesis, 1976
- Control of globin synthesis: The role of hemeJournal of Molecular Biology, 1972