Skip to main content
PMC home page
Proceedings of the National Academy of Sciences of the United States of America logoLink to Proceedings of the National Academy of Sciences of the United States of America
. 1979 Apr;76(4):1741–1745. doi: 10.1073/pnas.76.4.1741

Further studies on the mode of action of the heme-controlled translational inhibitor.

C de Haro, S Ochoa
PMCID: PMC383466  PMID: 377282

Abstract

We have isolated [de Haro, C. & Ochoa, S. (1978) Proc. Natl. Acad. Sci. USA 75, 2713-2716] a protein factor (eIF-2 stimulating protein, ESP) that is essential for formation of ternary and 40S initiation complexes by the eukaryotic polypeptide chain initiation factor 2 (eIF-2) at the low concentrations of eIF-2 present in reticulocyte lysates. The fact that stimulation of complex formation by ESP is virtually abolished when the small (38,000 daltons) subunit of eIF-2 is phosphorylated by ATP in the presence of eIF-2 kinase (heme-controlled inhibitor, HCI) is consistent with the notion that HCI inhibits translation in lysates by blocking the interaction of eIF-2 with ESP. Our present work, with highly purified eIF-2 and ESP, has additionally established that, unlike phosphorylation of the small subunit, phosphorylation of the middle (52,000 daltons) subunit of eIF-2, which does not lead to translational inhibition in lysates, does not affect eIF-2-ESP interaction. This provides further support for our model of translational inhibition by HCI.

Full text

PDF

Images in this article

1743Image
on p.1743

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Benne R., Edman J., Traut R. R., Hershey J. W. Phosphorylation of eukaryotic protein synthesis initiation factors. Proc Natl Acad Sci U S A. 1978 Jan;75(1):108–112. doi: 10.1073/pnas.75.1.108. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Benne R., Hershey J. W. Purification and characterization of initiation factor IF-E3 from rabbit reticulocytes. Proc Natl Acad Sci U S A. 1976 Sep;73(9):3005–3009. doi: 10.1073/pnas.73.9.3005. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Benne R., Wong C., Luedi M., Hershey J. W. Purification and characterization of initiation factor IF-E2 from rabbit reticulocytes. J Biol Chem. 1976 Dec 10;251(23):7675–7681. [PubMed] [Google Scholar]
  4. Dasgupta A., Das A., Roy R., Ralston R., Majumdar A., Gupta N. K. Protein synthesis in rabbit reticulocytes XXI. Purification and properties of a protein factor (Co-EIF-1) which stimulates Met-tRNAf binding to EIF-1. J Biol Chem. 1978 Sep 10;253(17):6054–6059. [PubMed] [Google Scholar]
  5. Datta A., de Haro C., Sierra J. M., Ochoa S. Role of 3':5'-cyclic-AMP-dependent protein kinase in regulation of protein synthesis in reticulocyte lysates. Proc Natl Acad Sci U S A. 1977 Apr;74(4):1463–1467. doi: 10.1073/pnas.74.4.1463. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Farrell P. J., Balkow K., Hunt T., Jackson R. J., Trachsel H. Phosphorylation of initiation factor elF-2 and the control of reticulocyte protein synthesis. Cell. 1977 May;11(1):187–200. doi: 10.1016/0092-8674(77)90330-0. [DOI] [PubMed] [Google Scholar]
  7. Gross M., Mendelewski J. Additional evidence that the hemin-controlled translational repressor from rabbit reticulocytes is a protein kinase. Biochem Biophys Res Commun. 1977 Jan 24;74(2):559–569. doi: 10.1016/0006-291x(77)90340-0. [DOI] [PubMed] [Google Scholar]
  8. Harbitz I., Hauge J. G. Purification and properties of a methionine formylmethionyl-tRNA-binding initiation factor from pig liver. Arch Biochem Biophys. 1976 Oct;176(2):766–778. doi: 10.1016/0003-9861(76)90221-6. [DOI] [PubMed] [Google Scholar]
  9. Kramer G., Cimadevilla J. M., Hardesty B. Specificity of the protein kinase activity associated with the hemin-controlled repressor of rabbit reticulocyte. Proc Natl Acad Sci U S A. 1976 Sep;73(9):3078–3082. doi: 10.1073/pnas.73.9.3078. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. LOWRY O. H., ROSEBROUGH N. J., FARR A. L., RANDALL R. J. Protein measurement with the Folin phenol reagent. J Biol Chem. 1951 Nov;193(1):265–275. [PubMed] [Google Scholar]
  11. Laemmli U. K. Cleavage of structural proteins during the assembly of the head of bacteriophage T4. Nature. 1970 Aug 15;227(5259):680–685. doi: 10.1038/227680a0. [DOI] [PubMed] [Google Scholar]
  12. Levin D., London I. M. Regulation of protein synthesis: activation by double-stranded RNA of a protein kinase that phosphorylates eukaryotic initiation factor 2. Proc Natl Acad Sci U S A. 1978 Mar;75(3):1121–1125. doi: 10.1073/pnas.75.3.1121. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Levin D., Ranu R. S., Ernst V., London I. M. Regulation of protein synthesis in reticulocyte lysates: phosphorylation of methionyl-tRNAf binding factor by protein kinase activity of translational inhibitor isolated from hemedeficient lysates. Proc Natl Acad Sci U S A. 1976 Sep;73(9):3112–3116. doi: 10.1073/pnas.73.9.3112. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Stanley W. M., Jr Preparation and analysis of L-( 35 S)methionine labeled transfer ribonucleic acids from rabbit liver. Anal Biochem. 1972 Jul;48(1):202–216. doi: 10.1016/0003-2697(72)90183-2. [DOI] [PubMed] [Google Scholar]
  15. Tahara S. M., Traugh J. A., Sharp S. B., Lundak T. S., Safer B., Merrick W. C. Effect of hemin on site-specific phosphorylation of eukaryotic initiation factor 2. Proc Natl Acad Sci U S A. 1978 Feb;75(2):789–793. doi: 10.1073/pnas.75.2.789. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Trachsel H., Staehelin T. Binding and release of eukaryotic initiation factor eIF-2 and GTP during protein synthesis initiation. Proc Natl Acad Sci U S A. 1978 Jan;75(1):204–208. doi: 10.1073/pnas.75.1.204. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Traugh J. A., Traut R. R. Characterization of protein kinases from rabbit reticulocytes. J Biol Chem. 1974 Feb 25;249(4):1207–1212. [PubMed] [Google Scholar]
  18. Walton G. M., Gill G. N. Nucleotide regulation of a eukaryotic protein synthesis initiation complex;. Biochim Biophys Acta. 1975 May 1;390(2):231–245. doi: 10.1016/0005-2787(75)90344-5. [DOI] [PubMed] [Google Scholar]
  19. Walton G. M., Gill G. N. Regulation of ternary (Met-tRNAf - GTP - eukaryotic initiation factor 2) protein synthesis initiation complex formation by the adenylate energy charge. Biochim Biophys Acta. 1976 Jan 19;418(2):195–203. doi: 10.1016/0005-2787(76)90069-1. [DOI] [PubMed] [Google Scholar]
  20. de Haro C., Datta A., Ochoa S. Mode of action of the hemin-controlled inhibitor of protein synthesis. Proc Natl Acad Sci U S A. 1978 Jan;75(1):243–247. doi: 10.1073/pnas.75.1.243. [DOI] [PMC free article] [PubMed] [Google Scholar]
  21. de Haro C., Ochoa S. Mode of action of the hemin-controlled inhibitor of protein synthesis: studies with factors from rabbit reticulocytes. Proc Natl Acad Sci U S A. 1978 Jun;75(6):2713–2716. doi: 10.1073/pnas.75.6.2713. [DOI] [PMC free article] [PubMed] [Google Scholar]

Articles from Proceedings of the National Academy of Sciences of the United States of America are provided here courtesy of National Academy of Sciences

RESOURCES