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Abstract Translation is the most error‐prone process in protein synthesis; however, it is important that accuracy is maintained because erroneous translation has been shown to affect all domains of life. Translational quality control is maintained by both proteins and RNA through intricate processes. The aminoacyl‐tRNA synthetases help maintain high levels of translational accuracy through the esterification of tRNA and proofreading mechanisms. tRNA is often recognized by an aminoacyl‐tRNA synthetase in a sequence and structurally dependent manner, sometimes involving modified nucleotides. Additionally, some proofreading mechanisms of aminoacyl‐tRNA synthetases require tRNA elements for hydrolysis of a noncognate aminoacyl‐tRNA. Finally, tRNA is also important for proper decoding of the mRNA message by codon and anticodon pairing. Here, recent developments regarding the importance of tRNA in maintenance of translational accuracy are reviewed. © 2019 IUBMB Life, 2019 © 2019 IUBMB Life, 71(8):1150–1157, 2019
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Bacterial wobble modifications of NNA‐decoding tRNAs
Abstract Nucleotides of transfer RNAs (tRNAs) are highly modified, particularly at the anticodon. Bacterial tRNAs that read A‐ending codons are especially notable. The U34 nucleotide canonically present in these tRNAs is modified by a wide range of complex chemical constituents. An additional two A‐ending codons are not read by U34‐containing tRNAs but are accommodated by either inosine or lysidine at the wobble position (I34 or L34). The structural basis for many N34 modifications in both tRNA aminoacylation and ribosome decoding has been elucidated, and evolutionary conservation of modifying enzymes is also becoming clearer. Here we present a brief review of the structure, function, and conservation of wobble modifications in tRNAs that translate A‐ending codons. © 2019 IUBMB Life, 2019 © 2019 IUBMB Life, 71(8):1158–1166, 2019
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- Award ID(s):
- 1818131
- PAR ID:
- 10460036
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- IUBMB Life
- Volume:
- 71
- Issue:
- 8
- ISSN:
- 1521-6543
- Page Range / eLocation ID:
- p. 1158-1166
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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