Pavlov Michael Y, Liljas Anders, Ehrenberg Måns
Department of Cell and Molecular Biology, Uppsala University, Husargatan 3, Box 596, Uppsala 75124, Sweden.
Department of Biochemistry and Structural Biology, Lund University, Box 124, 22100 Lund, Sweden.
Philos Trans R Soc Lond B Biol Sci. 2017 Mar 19;372(1716). doi: 10.1098/rstb.2016.0185.
Two sets of ribosome structures have recently led to two different interpretations of what limits the accuracy of codon translation by transfer RNAs. In this review, inspired by this intermezzo at the Ribosome Club, we briefly discuss accuracy amplification by energy driven proofreading and its implementation in genetic code translation. We further discuss general ways by which the monitoring bases of 16S rRNA may enhance the ultimate accuracy (d-values) and how the codon translation accuracy is reduced by the actions of Mg ions and the presence of error inducing aminoglycoside antibiotics. We demonstrate that complete freezing-in of cognate-like tautomeric states of ribosome-bound nucleotide bases in transfer RNA or messenger RNA is not compatible with recent experiments on initial codon selection by transfer RNA in ternary complex with elongation factor Tu and GTP. From these considerations, we suggest that the sets of 30S subunit structures from the Ramakrishnan group and 70S structures from the Yusupov/Yusupova group may, after all, reflect two sides of the same coin and how the structurally based intermezzo at the Ribosome Club may be resolved simply by taking the dynamic aspects of ribosome function into account.This article is part of the themed issue 'Perspectives on the ribosome'.
最近,两组核糖体结构引发了对于限制转运RNA进行密码子翻译准确性因素的两种不同解读。在这篇综述中,受核糖体俱乐部这段插曲的启发,我们简要讨论了能量驱动校对的准确性放大作用及其在遗传密码翻译中的实现方式。我们还进一步探讨了16S rRNA的监测碱基提高最终准确性(d值)的一般方式,以及镁离子的作用和诱导错误的氨基糖苷类抗生素的存在如何降低密码子翻译的准确性。我们证明,转运RNA或信使RNA中与核糖体结合的核苷酸碱基类似同源互变异构体状态的完全固定,与最近关于转运RNA在与延伸因子Tu和GTP形成的三元复合物中进行初始密码子选择的实验结果不相符。基于这些考虑,我们认为,拉马克里希南团队的30S亚基结构集和尤苏波夫/尤苏波娃团队的70S结构集,或许终究反映了同一枚硬币的两面,以及如何通过考虑核糖体功能的动态方面来简单地解决核糖体俱乐部基于结构的插曲。本文是主题为“核糖体的视角”特刊的一部分。