Small RNA Binding to 5′ mRNA Coding Region Inhibits Translational Initiation
Small RNA Binding to 5′ mRNA Coding Region Inhibits Translational Initiation
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DOI：
10.1016/j.molcel.2008.10.027
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发表时间：
2008-12-26
期刊：
影响因子：
16
通讯作者：
Vogel, Joerg
中科院分区：
文献类型：
--
作者：
Bouvier, Marie;Sharma, Cynthia M.;Vogel, Joerg
小非编码 RNA (sRNA) 主要通过掩蔽 Shine-Dalgarno (SD) 或 AUG 起始密码子序列来抑制细菌 mRNA，从而阻止 30S 核糖体进入，从而阻止翻译起始。然而，许多最近鉴定的 sRNA 缺乏明显的 SD 和 AUG 互补性，表明 sRNA 介导的翻译控制也可能发生在其他 mRNA 位点。我们报告沙门氏菌 RybB sRNA 通过与 5' 编码区配对来抑制 ompN mRNA 翻译。对 30S 与 ompN 和不相关 mRNA 结合的系统反义干扰的结果表明，即使没有 SD 和 AUG 起始密码子配对，sRNA 也可以通过将 mRNA 内的序列隔离到第五个密码子来充当翻译抑制子。这种用于 mRNA 5' 编码区翻译控制的“五密码子窗口”不仅对 sRNA 靶标预测具有影响，而且还可能适用于 RNA 热传感器和核糖开关等顺式调控系统。
Small noncoding RNAs (sRNAs) have predominantly been shown to repress bacterial mRNAs by masking the Shine-Dalgarno (SD) or AUG start codon sequence, thereby preventing 30S ribosome entry and, consequently, translation initiation. However, many recently identified sRNAs lack obvious SD and AUG complementarity, indicating that sRNA-mediated translational control could also take place at other mRNA sites. We report that Salmonella RybB sRNA represses ompN mRNA translation by pairing with the 5' coding region. Results of systematic antisense interference with 30S binding to ompN and unrelated mRNAs suggest that sRNAs can act as translational repressors by sequestering sequences within the mRNA down to the fifth codon, even without SD and AUG start codon pairing. This "five codon window" for translational control in the 5' coding region of mRNA not only has implications for sRNA target predictions but might also apply to cis-regulatory systems such as RNA thermosensors and riboswitches.