Mode of action of the hemin-controlled inhibitor of protein synthesis.
- 1 January 1978
- journal article
- research article
- Published by Proceedings of the National Academy of Sciences in Proceedings of the National Academy of Sciences
- Vol. 75 (1), 243-247
- https://doi.org/10.1073/pnas.75.1.243
Abstract
Despite the finding that the hemin-controlled translational inhibitor in reticulocyte lysates is a cyclic AMP-independent protein kinase that phosphorylates the small subunit of the initiation factor eIF-2, the mechanism of inhibition of translation remained unexplained. Whereas treatment of hemin-containing lysates with inhibitor in the presence of ATP inhibited translation, the same treatment of highly purified eIF-2 did not affect its ability to form a ternary complex with initiator Met-tRNA and GTP or a 40S initiation complex. We have isolated from ribosomal salt washes a protein (eIF-2 stimulating protein) that enhances the capacity of unphosphorylated eIF-2 to form ternary or 40S initiation complexes but has no effect on the phosphorylated factor. At low concentrations, eIF-2 is virtually inactive without this stimulating protein. Therefore, the translational inhibitor acts by converting eIF-2 to a form that is not stimulated by the stimulating protein.Keywords
This publication has 19 references indexed in Scilit:
- Translational control by protein kinase in Artemia salina and wheat germ.Proceedings of the National Academy of Sciences, 1977
- Mechanism of translational control by hemin in reticulocyte lysates.Proceedings of the National Academy of Sciences, 1977
- Phosphorylation of initiation factor eIF-2 and the control of reticulocyte protein synthesisCell, 1977
- Role of 3':5'-cyclic-AMP-dependent protein kinase in regulation of protein synthesis in reticulocyte lysates.Proceedings of the National Academy of Sciences, 1977
- Additional evidence that the hemin-controlled translational repressor from rabbit reticulocytes is a protein kinaseBiochemical and Biophysical Research Communications, 1977
- Partial reaction of peptide initiation inhibited by the reticulocyte hemin-controlled repressorBiochemical and Biophysical Research Communications, 1976
- Regulation of protein synthesis in rabbit reticulocyte lysates: purification and initial characterization of the cyclic 3':5'-AMP independent protein kinase of the heme-regulated translational inhibitor.Proceedings of the National Academy of Sciences, 1976
- Regulation of protein synthesis in reticulocyte lysates: phosphorylation of methionyl-tRNAf binding factor by protein kinase activity of translational inhibitor isolated from hemedeficient lysates.Proceedings of the National Academy of Sciences, 1976
- Specificity of the protein kinase activity associated with the hemin-controlled repressor of rabbit reticulocyte.Proceedings of the National Academy of Sciences, 1976
- PROTEIN MEASUREMENT WITH THE FOLIN PHENOL REAGENTJournal of Biological Chemistry, 1951