Despite the threat to human health posed by some single-stranded RNA viruses, little is understood about their assembly. The goal of this work is to introduce a new tool for watching an RNA genome direct its own packaging and encapsidation by proteins. Contrast variation small-angle X-ray scattering (CV-SAXS) is a powerful tool with the potential to monitor the changing structure of a viral RNA through this assembly process. The proteins, though present, do not contribute to the measured signal. As a first step in assessing the feasibility of viral genome studies, the structure of encapsidated MS2 RNA was exclusively detected with CV-SAXS and compared with a structure derived from asymmetric cryo-EM reconstructions. Additional comparisons with free RNA highlight the significant structural rearrangements induced by capsid proteins and invite the application of time-resolved CV-SAXS to reveal interactions that result in efficient viral assembly.

中文翻译：

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通过小角度 X 射线散射对比变化可视化病毒基因组。


尽管一些单链RNA病毒对人类健康构成威胁，但人们对它们的组装却知之甚少。这项工作的目标是引入一种新工具来观察 RNA 基因组通过蛋白质指导其自身的包装和衣壳化。对比度变化小角 X 射线散射 (CV-SAXS) 是一种强大的工具，有潜力通过该组装过程监测病毒 RNA 的结构变化。这些蛋白质虽然存在，但对测量信号没有贡献。作为评估病毒基因组研究可行性的第一步，我们专门使用 CV-SAXS 检测了衣壳化的 MS2 RNA 结构，并与源自不对称冷冻电镜重建的结构进行了比较。与游离 RNA 的其他比较突出了衣壳蛋白诱导的显着结构重排，并邀请应用时间分辨 CV-SAXS 来揭示导致有效病毒组装的相互作用。