Promotion of Met-tRNA i Met Binding to Ribosomes by yIF2, a Bacterial IF2 Homolog in Yeast
10.1126/science.280.5370.1757
Crossref journal-article
American Association for the Advancement of Science (AAAS)
Science (221)
Abstract

Delivery of the initiator methionine transfer RNA (Met-tRNA i Met ) to the ribosome is a key step in the initiation of protein synthesis. Previous results have indicated that this step is catalyzed by the structurally dissimilar translation factors in prokaryotes and eukaryotes—initiation factor 2 (IF2) and eukaryotic initiation factor 2 (eIF2), respectively. A bacterial IF2 homolog has been identified in both eukaryotes and archaea. By using a combination of molecular genetic and biochemical studies, the Saccharomyces cerevisiae IF2 homolog is shown to function in general translation initiation by promoting Met-tRNA i Met binding to ribosomes. Thus, the mechanism of protein synthesis in eukaryotes and prokaryotes is more similar than was previously realized.

Bibliography

Choi, S. K., Lee, J. H., Zoll, W. L., Merrick, W. C., & Dever, T. E. (1998). Promotion of Met-tRNA i Met Binding to Ribosomes by yIF2, a Bacterial IF2 Homolog in Yeast. Science, 280(5370), 1757–1760.

Authors 5
  1. Sang Ki Choi (first)
  2. Joon H. Lee (additional)
  3. Wendy L. Zoll (additional)
  4. William C. Merrick (additional)
  5. Thomas E. Dever (additional)
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  29. We thank G. Pavitt for purified yeast eIF2 M. Cigan for the IMT4 plasmid C. Moehle and S. Green for plasmid pRG166 P. Sutrave and S. Hughes for the FUN12 cDNA clone and A. Sachs for advice on the yeast in vitro translation assays; A. Hinnebusch G. Pavitt J. Anderson and L. Phan and members of the Dever and Hinnebusch laboratories for helpful discussions; and A. Hinnebusch and R. Rolfes for comments on the manuscript. We thank T. Donahue for discussions and for communicating results before publication. Supported in part by National Institutes of Health grant 26796 (W.C.M.) and a training grant in cellular and molecular biology (GM08056 to W.L.Z.).
Dates
Type When
Created 23 years ago (July 27, 2002, 5:37 a.m.)
Deposited 1 year, 7 months ago (Jan. 13, 2024, 12:27 a.m.)
Indexed 2 months, 4 weeks ago (May 27, 2025, 8:57 a.m.)
Issued 27 years, 2 months ago (June 12, 1998)
Published 27 years, 2 months ago (June 12, 1998)
Published Print 27 years, 2 months ago (June 12, 1998)
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@article{Choi_1998, title={Promotion of Met-tRNA i Met Binding to Ribosomes by yIF2, a Bacterial IF2 Homolog in Yeast}, volume={280}, ISSN={1095-9203}, url={http://dx.doi.org/10.1126/science.280.5370.1757}, DOI={10.1126/science.280.5370.1757}, number={5370}, journal={Science}, publisher={American Association for the Advancement of Science (AAAS)}, author={Choi, Sang Ki and Lee, Joon H. and Zoll, Wendy L. and Merrick, William C. and Dever, Thomas E.}, year={1998}, month=jun, pages={1757–1760} }