Structural determinants of viral RNAs resistant to exoribonucleases in the alphavirus supergroup

甲病毒超群中抗核糖核酸外切酶的病毒RNA的结构决定因素

• 批准号: 10311545
• 负责人: Quentin Vicens
• 金额: $ 19.09万
• 依托单位: UNIVERSITY OF COLORADO DENVER
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-12-15 至 2023-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10311545
• 关键词: 3-Dimensional; Address; Alphavirus; Biochemical; Biological Assay; Biology; Chemicals; Computing Methodologies; Data; Digestion; Distant; Elements; Evolution; Exonuclease; Exoribonucleases; Family; Flavivirus; Foundations; Future; Genome; Hepatitis E virus; Infection; Knowledge; Learning; Light; Membrane Proteins; Methods; Modeling; Mutagenesis; Nucleotides; Pathogenicity; Pathway interactions; Plant Viruses; Process; Production; RNA; RNA Folding; RNA Viruses; Resistance; Role; Structure; Surface; Taxonomy; Techniques; Testing; Time; Tombusviridae; Variant; Viral; Virus; Virus Diseases; Work; X-Ray Crystallography; base; chikungunya; human pathogen; improved; member; molecular clock; resistance mechanism; structural biology; three dimensional structure; viral RNA; virome

Summary Structured elements within genomes of RNA viruses have critical roles during infection. Examples are exonuclease-resistant RNAs (xrRNAs) that resist degradation by host cellular exoribonucleases, leading to the production of viral subgenomic RNAs. Detailed three-dimensional structural studies of xrRNAs from flaviviruses and a subset of plant viruses led to a mechanistic model in which xrRNAs block enzymatic digestion using a ring-like structure that braces against the protein surface. Very recently, a new xrRNA class was found in the more distantly related and diverse alphavirus supergroup, which includes several important human pathogens. Initially found in the Benyviridae and several other virus families, this xrRNA has no obvious similarity to those previously studied. Thus, we do not know how it folds, how it blocks the host exonuclease, and how widespread it is distributed. These fundamental gaps in knowledge block progress in understanding what could be a pervasive and important RNA element in the alphavirus supergroup and beyond. In addition, because xrRNAs have been found in several major superfamilies of viruses, they may represent a `molecular clock' that could help us understand virus evolution and pathogenicity. To that end, understanding the fold of the xrRNA from Benyviridae is critical. Here, we propose to address these key unknowns and enable future studies by pursuing two aims. First, we will determine the structural basis of exonuclease resistance by the new class of xrRNA from Benyviridae. This aim will use advanced structural biology methods to inform not only on the mechanism for resistance to degradation, but also enable accurate searches for similar motifs throughout the alphavirus supergroup. Second, we will determine the distribution of the xrRNA fold from Benyviridae across the viral world. This aim combines computational and biochemical approaches, which has previously led to successfully characterizing xrRNAs that were also considered `exotic' at the time. Exploring how widespread this new class of xrRNAs is has the potential to illuminate the biology of viruses of diverse but related alphavirus supergroup members, expand our knowledge of RNA structure in the viral world, and motivate futures studies into the roles of xrRNAs in virus-induced disease.

概括 RNA 病毒基因组内的结构元件在感染过程中发挥着关键作用。例子是 核酸外切酶抗性 RNA (xrRNA) 可抵抗宿主细胞核糖核酸外切酶的降解，从而导致 病毒亚基因组RNA的产生。黄病毒 xrRNA 的详细三维结构研究 植物病毒的一个子集产生了一个机制模型，其中 xrRNA 使用 支撑蛋白质表面的环状结构。最近，一个新的 xrRNA 类别在 关系更远、更多样化的甲病毒超群，其中包括几种重要的人类病原体。 该 xrRNA 最初在 Benyviridae 和其他几个病毒科中发现，与那些病毒没有明显的相似性。 以前研究过。因此，我们不知道它如何折叠，如何阻断宿主核酸外切酶，以及如何 它分布广泛。这些知识上的根本差距阻碍了我们理解什么可以取得进展 是甲病毒超群及其他超群中普遍且重要的RNA元件。另外，因为 xrRNA 已在几个主要病毒超科中被发现，它们可能代表一个“分子钟” 可以帮助我们了解病毒的进化和致病性。为此，了解 xrRNA 的折叠 来自苯尼病毒科的病毒至关重要。在这里，我们建议解决这些关键的未知因素，并通过以下方式实现未来的研究： 追求两个目标。首先，我们将通过新的核酸外切酶抗性确定外切核酸酶抗性的结构基础。 来自 Benyviridae 的 xrRNA 类别。这一目标将使用先进的结构生物学方法来不仅告知 抗降解机制，而且还能够准确搜索相似的基序 整个甲病毒超群。其次，我们将确定 xrRNA 折叠的分布 病毒世界中的本尼病毒科。这一目标结合了计算和生化方法， 此前，我们已经成功地表征了当时也被认为是“异国情调”的xrRNA。 探索这种新型 xrRNA 的广泛分布有可能阐明病毒的生物学特性 多样化但相关的甲病毒超群成员，扩展我们对病毒世界中RNA结构的了解， 并激发未来对 xrRNA 在病毒引起的疾病中的作用的研究。