Structural insights into ribosome translocation.
Structural insights into ribosome translocation.
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DOI：
10.1002/wrna.1354
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发表时间：
2016-09
期刊：
影响因子：
--
通讯作者：
Ermolenko DN
中科院分区：
文献类型：
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作者：
Ling C;Ermolenko DN
在蛋白质合成过程中，tRNA和mRNA从核糖体的A位转移到P位，再到E位，从而使核糖体能够翻译一个又一个密码子的mRNA。核糖体沿mRNA的移位是由普遍保守的核糖体GTP酶、细菌中的延伸因子G(EF-G)和真核生物中的延伸因子2(EF-2)诱导的。最近的结构和单分子研究表明，tRNA和mRNA在核糖体内的移位伴随着平行于亚基间界面平面的大小核糖体亚基之间的循环正向和反向旋转。此外，在核糖体易位期间，小核糖体亚基的‘头’结构域相对于小核糖体亚基的其余部分绕与亚基间旋转轴垂直的轴进行前后旋转。TRNA/mRNA易位也与EF-G的IV结构域对接到核糖体小亚基的A位相连，后者将核糖体和tRNA的热驱动运动转化为核糖体内tRNA/mRNA的正向移位。尽管最近对核糖体易位的分子机制的了解取得了巨大的进展，但核糖体、EF-G和tRNA在易位过程中的结构重排序列仍未完全确定，有待进一步研究。《电线RNA 2016》，7：620-636。DOI：10.1002/wrna.1354有关本文的更多资源，请访问WIRESS网站。
During protein synthesis, tRNA and mRNA are translocated from the A to P to E sites of the ribosome thus enabling the ribosome to translate one codon of mRNA after the other. Ribosome translocation along mRNA is induced by the universally conserved ribosome GTPase, elongation factor G (EF‐G) in bacteria and elongation factor 2 (EF‐2) in eukaryotes. Recent structural and single‐molecule studies revealed that tRNA and mRNA translocation within the ribosome is accompanied by cyclic forward and reverse rotations between the large and small ribosomal subunits parallel to the plane of the intersubunit interface. In addition, during ribosome translocation, the ‘head’ domain of small ribosomal subunit undergoes forward‐ and back‐swiveling motions relative to the rest of the small ribosomal subunit around the axis that is orthogonal to the axis of intersubunit rotation. tRNA/mRNA translocation is also coupled to the docking of domain IV of EF‐G into the A site of the small ribosomal subunit that converts the thermally driven motions of the ribosome and tRNA into the forward translocation of tRNA/mRNA inside the ribosome. Despite recent and enormous progress made in the understanding of the molecular mechanism of ribosome translocation, the sequence of structural rearrangements of the ribosome, EF‐G and tRNA during translocation is still not fully established and awaits further investigation. WIREs RNA 2016, 7:620–636. doi: 10.1002/wrna.1354 For further resources related to this article, please visit the WIREs website.