Department of Chemistry and Biochemistry, Alberta RNA Research and Training Institute, University of Lethbridge, 4401 University Drive, Lethbridge, AB T1K 3M4, Canada.
Department Of Chemistry And Biochemistry, University of Montana, Missoula, MT 59812, USA.
Viruses. 2020 Feb 8;12(2):190. doi: 10.3390/v12020190.
Viral infections are responsible for numerous deaths worldwide. Flaviviruses, which contain RNA as their genetic material, are one of the most pathogenic families of viruses. There is an increasing amount of evidence suggesting that their 5' and 3' non-coding terminal regions are critical for their survival. Information on their structural features is essential to gain detailed insights into their functions and interactions with host proteins. In this study, the 5' and 3' terminal regions of Murray Valley encephalitis virus and Powassan virus were examined using biophysical and computational modeling methods. First, we used size exclusion chromatography and analytical ultracentrifuge methods to investigate the purity of transcribed RNAs. Next, we employed small-angle X-ray scattering techniques to study solution conformation and low-resolution structures of these RNAs, which suggest that the 3' terminal regions are highly extended as compared to the 5' terminal regions for both viruses. Using computational modeling tools, we reconstructed 3-dimensional structures of each RNA fragment and compared them with derived small-angle X-ray scattering low-resolution structures. This approach allowed us to reinforce that the 5' terminal regions adopt more dynamic structures compared to the mainly double-stranded structures of the 3' terminal regions.
病毒感染是造成全球众多死亡的原因之一。黄病毒属含有 RNA 作为遗传物质，是最具致病性的病毒家族之一。越来越多的证据表明，它们的 5'和 3'非编码末端区域对其存活至关重要。了解它们的结构特征对于深入了解它们的功能以及与宿主蛋白的相互作用至关重要。在这项研究中，使用生物物理和计算建模方法研究了默里谷脑炎病毒和波瓦桑病毒的 5'和 3'末端区域。首先，我们使用大小排阻色谱法和分析超速离心法来研究转录 RNA 的纯度。接下来，我们采用小角度 X 射线散射技术研究了这些 RNA 的溶液构象和低分辨率结构，结果表明，与 5'末端区域相比，两种病毒的 3'末端区域都高度延伸。使用计算建模工具，我们重建了每个 RNA 片段的 3 维结构，并将其与衍生的小角度 X 射线散射低分辨率结构进行了比较。这种方法使我们能够强化这样一种观点，即与 3'末端区域主要的双链结构相比，5'末端区域采用了更具动态的结构。
