Crystal structure of an initiation factor bound to the 30S ribosomal subunit
Crystal structure of an initiation factor bound to the 30S ribosomal subunit
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DOI：
10.1126/science.1057766
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发表时间：
2001-01-19
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：
Carter, AP;Clemons, WM;Ramakrishnan, V
在信使RNA上的正确位置启动翻译对于精确的蛋白质合成是必不可少的。在原核生物中，这一过程需要三个起始因子：IF1，IF2和IF3。本文报道了IF1和30S核糖体亚基复合物的晶体结构，IF1的结合封闭了核糖体A位点，并将功能重要的碱基A1492和A1493从16S RNA的螺旋44中翻转出来，将它们埋在IF1的口袋中。IF1的结合引起H44构象的长程变化，并导致30S结构域相对于彼此的移动。该结构解释了核糖体A位点的局部变化如何导致30S亚基构象的全局改变。
Initiation of translation at the correct position on messenger RNA is essential for accurate protein synthesis. In prokaryotes, this process requires three initiation factors: IF1, IF2, and IF3, Here we report the crystal structure of a complex of IF1 and the 30S ribosomal subunit, Binding of IF1 occludes the ribosomal A site and flips out the functionally important bases A1492 and A1493 from helix 44 of 16S RNA, burying them in pockets in IF1. The binding of IF1 causes long-range changes in the conformation of H44 and Leads to movement of the domains of 30S with respect to each other. The structure explains how localized changes at the ribosomal A site lead to global alterations in the conformation of the 30S subunit.