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Updated: May 10, 2026

Dual DNA Rulers to Study the Mechanism of Ribosome Translocation with Single-Nucleotide Resolution
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Dual DNA Rulers to Study the Mechanism of Ribosome Translocation with Single-Nucleotide Resolution

Published on: July 8, 2019

リボソームによるストップコドンの解読中の異常な塩基配列

Israel S Fernández1, Chyan Leong Ng, Ann C Kelley

  • 1MRC Laboratory of Molecular Biology, Cambridge CB2 0QH, UK.

Nature
|July 2, 2013
PubMed
まとめ

偽ウリジンの改変により,トランスファーRNA (tRNA) がストップコドンを読み取ることができ,異常な塩基配列が求められます. この構造的研究はリボソームを明らかにします.

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Transfer RNA Synthesis02:36

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One of the unique features of tRNA is the presence of modified bases. In some tRNAs, modified bases account for nearly 20% of the total bases in the molecule. Altogether, these unusual bases protect the tRNA from enzymatic degradation by RNases.
Each of these chemical modifications is carried by a specific enzyme, post-transcription. All of these enzymes have unique base and site-specificity. Methylation, the most common chemical modification, is carried by at least nine different enzymes, with...
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Aminoacyl-tRNA synthetases are present in both eukaryotes and bacteria. Though eukaryotes have 20 different aminoacyl-tRNA synthetases to couple to 20 amino acids, many bacteria do not have genes for all of these aminoacyl-tRNA synthetases. Despite this, they still use all 20 amino acids to synthesize their proteins. For instance, some bacteria do not have the gene encoding the enzyme that couples glutamine with its partner tRNA. In these organisms, one enzyme adds glutamic acid to all of the...