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Eukaryotic Polyribosome Profile Analysis
Published on: June 15, 2010
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A novel function for eukaryotic elongation factor 3: Inhibition of stop codon readthrough in yeast
Soushi Kobayashi1, Akira Kaji2, Hideko Kaji3
1Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, 3610 Hamilton Walk, Philadelphia, PA, 19104, USA; Department of Biochemistry and Molecular Biology, Thomas Jefferson University, 1020 Locust Street, Philadelphia, PA, 19107, USA.
Archives of Biochemistry and Biophysics
|March 22, 2023
Summary
Eukaryotic elongation factor 3 (eEF3) assists in protein synthesis termination. This study shows eEF3 helps release factors terminate translation, preventing readthrough of stop codons.
Area of Science:
- Molecular Biology
- Protein Synthesis
- Yeast Genetics
Background:
- Eukaryotic elongation factor 3 (eEF3) is an essential yeast ABCF ATPase.
- Previous research indicated eEF3's role in mRNA release from polysomes.
Purpose of the Study:
- To investigate the function of eEF3 in protein synthesis termination.
- To elucidate the mechanism by which eEF3 interacts with release factors.
Main Methods:
- Utilized a cell-free cricket paralysis virus (CrPV) IRES-mediated bicistronic mRNA translation system.
- Employed yeast S30 extract with partial removal of eEF3.
- Analyzed firefly luciferase expression and polysome profiles.
Main Results:
- Partial removal of eEF3 increased readthrough of the upstream ORF's stop codon.
- eEF3 was found to enhance the release of luciferase from polysomes by eukaryotic release factor 1 (eRF1) and eRF3.
- Demonstrated eEF3's role in facilitating normal protein synthesis termination.
Conclusions:
- eEF3 plays a crucial role in yeast protein synthesis termination.
- eEF3 acts as an accessory factor for eukaryotic release factors (eRFs).
- This function of eEF3 is vital for accurate translation termination.
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