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PubMed · 11743004

A dynamic competition between release factor 2 and the tRNA(Sec) decoding UGA at the recoding site of Escherichia coli formate dehydrogenase H.

J B Mansell·D Guévremont·E S Poole·W P Tate
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Abstract

Factors affecting competition between termination and elongation in vivo during translation of the fdhF selenocysteine recoding site (UGA) were studied with wild-type and modified fdhF sequences. Altering sequences surrounding the recoding site UGA without affecting RNA secondary structure indicated that the kinetics of stop signal decoding have a significant influence on selenocysteine incorporation efficiency. The UGA in the wild-type fdhF sequence remains 'visible' to the factor and forms a site-directed cross-link when mRNA stem-loop secondary structure is absent, but not when it is present. The timing of the secondary structure unfolding during translation may be a critical feature of competition between release factor 2 and tRNA(Sec) for decoding UGA. Increasing the cellular concentration of either of these decoding molecules for termination or selenocysteine incorporation showed that they were able to compete for UGA by a kinetic competition that is dynamic and dependent on the Escherichia coli growth rate. The tRNA(Sec)-mediated decoding can compete more effectively for the UGA recoding site at lower growth rates, consistent with anaerobic induction of fdhF expression.

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Base SequenceEscherichia coliFormate DehydrogenasesHydrogenaseMolecular Sequence DataMultienzyme ComplexesNucleic Acid ConformationPeptide Termination FactorsProtein BiosynthesisRNA, Transfer, Amino Acid-SpecificJournal ArticleResearch Support, Non-U.S. Gov't

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J B Mansell, D Guévremont, E S Poole, W P Tate. 2001-12-17. A dynamic competition between release factor 2 and the tRNA(Sec) decoding UGA at the recoding site of Escherichia coli formate dehydrogenase H.. https://doi.org/10.1093/emboj%2F20.24.7284

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