Structural Insights into Riboswitch Control of the Biosynthesis of Queuosine, a Modified Nucleotide Found in the Anticodon of tRNA
Structural Insights into Riboswitch Control of the Biosynthesis of Queuosine, a Modified Nucleotide Found in the Anticodon of tRNA
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DOI：
10.1016/j.molcel.2009.02.019
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发表时间：
2009-03-27
期刊：
影响因子：
16
通讯作者：
Feigon, Juli
中科院分区：
文献类型：
--
作者：
Kang, Mijeong;Peterson, Robert;Feigon, Juli
修饰的核苷酸队列 (Q) 几乎普遍存在于特定 tRNA 的反密码子摆动位置中。在许多细菌中，Q 的生物合成受到一类称为核糖开关的 mRNA 调节元件的调节。 preQ(1) 核糖开关存在于参与 Q 前体 preQ(0) 和 preQ(1) 合成的细菌基因 5'UTR 中，包含已知的最小适体结构域。我们报道了与 preQ(1) 结合的枯草芽孢杆菌 preQ(1) 核糖开关适体结构域的溶液结构，它是一个独特的紧凑假结，具有三个环和两个茎，在两个茎之间的连接处封装了 preQ(1)。假结仅在存在 preQ(1) 的情况下形成，并且适体结构域的 3' A 丰富尾部是假结的组成部分。在没有 preQ(1) 的情况下，富含 A 的尾部形成反终止子的一部分。这些结构研究提供了对 preQ(1) 生物合成的核糖开关转录控制的深入了解。(1)
The modified nucleotide queuosine (Q) is almost universally found in the anticodon wobble position of specific tRNAs. In many bacteria, biosynthesis of Q is modulated by a class of regulatory mRNA elements called riboswitches. The preQ(1) riboswitch, found in the 5'UTR of bacterial genes involved in synthesis of the Q precursors preQ(0) and preQ(1), contains the smallest known aptamer domain. We report the solution structure of the preQ(1) riboswitch aptamer domain from Bacillus subtilis bound to preQ(1), which is a unique compact pseudoknot with three loops and two stems that encapsulates preQ(1) at the junction between the two stems. The pseudoknot only forms in the presence of preQ(1), and the 3' A-rich tail of the aptamer domain is an integral part of the pseudoknot. In the absence of preQ(1), the A-rich tail forms part of the antiterminator. These structural studies provide insight into riboswitch transcriptional control of preQ(1) biosynthesis.(1)