Nucleoside modifications in the regulation of gene expression: focus on tRNA.

Nucleoside modifications in the regulation of gene expression: focus on tRNA.
Cell Mol Life Sci. 2016 Apr 19;
Authors: Duechler M, Leszczyńska G, Sochacka E, Nawrot B
Abstract
Both, DNA and RNA nucleoside modifications contribute to the complex multi-level regulation of gene expression. Modified bases in tRNAs modulate protein translation rates in a highly dynamic manner. Synonymous codons, which differ by the third nucleoside in the triplet but code for the same amino acid, may be utilized at different rates according to codon-anticodon affinity. Nucleoside modifications in the tRNA anticodon loop can favor the interaction with selected codons by stabilizing specific base pairs. Similarly, weakening of base pairing can discriminate against binding to near-cognate codons. mRNAs enriched in favored codons are translated in higher rates constituting a fine-tuning mechanism for protein synthesis. This so-called codon bias establishes a basic protein level, but sometimes it is necessary to further adjust the production rate of a particular protein to actual requirements, brought by, e.g., stages in circadian rhythms, cell cycle progression or exposure to stress. Such an adjustment is realized by the dynamic change of tRNA modifications resulting in the preferential translation of mRNAs coding for example for stress proteins to facilitate cell survival. Furthermore, tRNAs contribute in an entirely different way to another, less specific ...

Source: Cellular and Molecular Life Sciences : CMLS - April 18, 2016 Category: Cytology Authors: Duechler M, Leszczyńska G, Sochacka E, Nawrot B Tags: Cell Mol Life Sci Source Type: research