Recognition of cognate transfer RNA by the 30S ribosomal subunit
Recognition of cognate transfer RNA by the 30S ribosomal subunit
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DOI：
10.1126/science.1060612
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发表时间：
2001-05-04
期刊：
影响因子：
56.9
通讯作者：
Ramakrishnan, V
中科院分区：
文献类型：
--
作者：
Ogle, JM;Brodersen, DE;Ramakrishnan, V
在抗生素paromomycin存在和不存在的情况下，30S核糖体亚基与A位点的信使RNA和同源转移RNA复合物的晶体结构都在3.1 - 3.3埃的分辨率下得到了解析。同源转移RNA （tRNA）结合可诱导30S亚基的全局结构域移动，并改变16S RNA中普遍保守的必需碱基A1492、A1493和G530的构象。这些碱基与密码子和反密码子之间的前两个碱基对的小凹槽密切相互作用，从而感知沃森-克里克碱基对几何形状并区分近同源tRNA。密码子的第三个或“摆动”位置可以自由容纳某些非规范碱基对。通过部分诱导这些结构变化，paromomycin促进了近同源trna的结合。
Crystal structures of the 30S ribosomal subunit in complex with messenger RNA and cognate transfer RNA in the A site, both in the presence and absence of the antibiotic paromomycin, have been solved at between 3.1 and 3.3 angstroms resolution. Cognate transfer RNA (tRNA) binding induces global domain movements of the 30S subunit and changes in the conformation of the universally conserved and essential bases A1492, A1493, and G530 of 16S RNA. These bases interact intimately with the minor groove of the first two base pairs between the codon and anticodon, thus sensing Watson-Crick base-pairing geometry and discriminating against near-cognate tRNA, The third, or "wobble," position of the codon is free to accommodate certain noncanonical base pairs. By partially inducing these structural changes, paromomycin facilitates binding of near-cognate tRNAs.