2'-O-Methylation can increase the abundance and lifetime of alternative RNA conformational states.
2'-O-Methylation can increase the abundance and lifetime of alternative RNA conformational states.
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DOI：
10.1093/nar/gkaa928
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发表时间：
2020-12-02
影响因子：
14.9
通讯作者：
Al-Hashimi HM
中科院分区：
文献类型：
--
作者：
Abou Assi H;Rangadurai AK;Shi H;Liu B;Clay MC;Erharter K;Kreutz C;Holley CL;Al-Hashimi HM
2'-O-甲基 (Nm) 是一种高度丰富的转录后 RNA 修饰，通过尚未完全了解的机制发挥着重要的生物学作用。有证据表明，Nm 可以通过使核糖褶皱平衡偏向典型双链体中形成的 C3'-endo 构象来改变 RNA 的生物活性。然而，人们对 Nm 如何更广泛地改变含有凸起和内部环的柔性 RNA 的动态整体知之甚少。在这里，使用 NMR 和 HIV-1 反式激活反应 (TAR) 元件作为模型系统，我们表明 Nm 优先稳定 Nm 修饰的核苷酸配对的替代二级结构，将低密度短寿命激发态的丰度和寿命增加多达 10 倍。稳定程度随着 Nm 修饰数量的增加而增加，并且还取决于 Mg2+。通过 phi 值分析，Nm 修饰还为构象交换的过渡态结构提供了罕见的见解。我们的结果表明，Nm 可以通过调节 Nm 修饰的 RNA 的二级结构整体来改变其生物活性，并确立 Nm 作为发现和表征 RNA 激发态构象的工具的实用性。
2′-O-Methyl (Nm) is a highly abundant post-transcriptional RNA modification that plays important biological roles through mechanisms that are not entirely understood. There is evidence that Nm can alter the biological activities of RNAs by biasing the ribose sugar pucker equilibrium toward the C3′-endo conformation formed in canonical duplexes. However, little is known about how Nm might more broadly alter the dynamic ensembles of flexible RNAs containing bulges and internal loops. Here, using NMR and the HIV-1 transactivation response (TAR) element as a model system, we show that Nm preferentially stabilizes alternative secondary structures in which the Nm-modified nucleotides are paired, increasing both the abundance and lifetime of low-populated short-lived excited states by up to 10-fold. The extent of stabilization increased with number of Nm modifications and was also dependent on Mg2+. Through phi-value analysis, the Nm modification also provided rare insights into the structure of the transition state for conformational exchange. Our results suggest that Nm could alter the biological activities of Nm-modified RNAs by modulating their secondary structural ensembles as well as establish the utility of Nm as a tool for the discovery and characterization of RNA excited state conformations.
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DOI：
10.1261/rna.065136.117
发表时间：
2018-04
期刊：
RNA (New York, N.Y.)
影响因子：
--
作者：
Didychuk AL;Butcher SE;Brow DA
通讯作者：
Brow DA
影响因子：
14.9
作者：
Chu, Chia-Chieh;Plangger, Raphael;Al-Hashimi, Hashim M.
通讯作者：
Al-Hashimi, Hashim M.
影响因子：
16.6
作者：
Alvey HS;Gottardo FL;Nikolova EN;Al-Hashimi HM
通讯作者：
Al-Hashimi HM
影响因子：
4.5
作者：
Dönmez, G;Hartmuth, K;Lührmann, R
通讯作者：
Lührmann, R
影响因子：
64.8
作者：
Cavaille, J;Nicoloso, M;Bachellerie, JP
通讯作者：
Bachellerie, JP