Back to Search Start Over

How tRNAs dictate nuclear codon reassignments: Only a few can capture non-cognate codons.

How tRNAs dictate nuclear codon reassignments: Only a few can capture non-cognate codons.

Authors :
Kollmar, Martin
Mühlhausen, Stefanie
Source :
RNA Biology; 2017, Vol. 14 Issue 3, p293-299, 7p
Publication Year :
2017

Abstract

mRNA decoding by tRNAs and tRNA charging by aminoacyl-tRNA synthetases are biochemically separated processes that nevertheless in general involve the same nucleotides. The combination of charging and decoding determines the genetic code. Codon reassignment happens when a differently charged tRNA replaces a former cognate tRNA. The recent discovery of the polyphyly of the yeast CUG sense codon reassignment challenged previous mechanistic considerations and led to the proposal of the so-calledtRNA loss driven codon reassignmenthypothesis. Accordingly, codon capture is caused by loss of a tRNA or by mutations in the translation termination factor, subsequent reduction of the codon frequency through reduced translation fidelity and final appearance of a new cognate tRNA. Critical for codon capture are sequence and structure of the new tRNA, which must be compatible with recognition regions of aminoacyl-tRNA synthetases. The proposed hypothesis applies to all reported nuclear and organellar codon reassignments. [ABSTRACT FROM PUBLISHER]

Details

Language :
English
ISSN :
15476286
Volume :
14
Issue :
3
Database :
Complementary Index
Journal :
RNA Biology
Publication Type :
Academic Journal
Accession number :
121925564
Full Text :
https://doi.org/10.1080/15476286.2017.1279785