Characterization of the Molecular Interactions That Govern the Packaging of Viral RNA Segments into Rift Valley Fever Phlebovirus Particles.
Characterization of the Molecular Interactions That Govern the Packaging of Viral RNA Segments into Rift Valley Fever Phlebovirus Particles.
复制标题
控制病毒 RNA 片段包装成裂谷热白蛉病毒颗粒的分子相互作用的表征。
DOI：
10.1128/jvi.00429-21
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发表时间：
2021
影响因子：
5.4
通讯作者：
Makino,Shinji
中科院分区：
文献类型：
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作者：
Tercero,Breanna;Narayanan,Krishna;Terasaki,Kaori;Makino,Shinji
裂谷热静脉病毒（RVFV）具有单链、负义RNA基因组，由L、M和S片段组成。病毒粒子携带两种包膜糖蛋白Gn和Gc，沿着有核糖核蛋白复合物（RNP），RNP由携带N蛋白和病毒聚合酶L蛋白的双核苷酸化基因组组成。定量分析包装成RVFV颗粒的病毒RNA片段的概况表明，所有三个基因组RNA片段具有相似的包装能力，而在反基因组RNA片段中，作为表达RVFV毒力因子NS的mRNA的转录模板的反基因组S RNA显示出显著更高的包装能力。为了描述控制RVFV RNA片段包装的因素，我们表征了RVFV感染细胞中Gn和病毒RNP之间的相互作用。免疫共沉淀分析表明，在RVFV感染的细胞中，Gn与N蛋白、L蛋白和病毒RNA相互作用。此外，紫外线交联和免疫沉淀分析显示，第一次在布尼亚病毒，Gn和RVFV感染的细胞中的所有病毒RNA片段之间的直接相互作用的存在。值得注意的是，Gn结合RVFV RNA片段的能力的分析表明与它们各自的包装能力正相关，并强调了Gn对反基因组S RNA的结合偏好，在反基因组RNA片段中，这表明存在将反基因组S RNA掺入感染性RVFV颗粒的选择机制。总的来说，我们的研究结果阐明了Gn和病毒RNA片段之间的直接相互作用的重要性，在确定其效率纳入RVFV particle.IMPORTANCERift谷热静脉病毒，布尼亚病毒，是一种蚊媒，分段RNA病毒，可导致严重的疾病，在人类和反刍动物。RVFV生命周期中的一个重要步骤是病毒RNA片段的包装，以产生感染性病毒颗粒，用于传播到新宿主。然而，在布尼亚病毒中调节病毒RNA包装效率的机制方面存在关键的知识空白。我们研究RVFV中RNA包装机制的研究揭示了病毒包膜糖蛋白Gn与感染细胞中病毒RNA片段之间的直接相互作用，这在布尼亚病毒中尚属首次。此外，我们的数据强烈表明Gn和病毒RNA之间的直接相互作用在确定将病毒RNA片段掺入RVFV颗粒的效率中的关键作用。阐明RVFV中RNA包装的基本机制对于开发抗病毒药物和减毒活疫苗具有重要价值。
Rift Valley fever phlebovirus (RVFV) has a single-stranded, negative-sense RNA genome, consisting of L, M, and S segments. The virion carries two envelope glycoproteins, Gn and Gc, along with ribonucleoprotein complexes (RNPs), composed of encapsidated genomes carrying N protein and the viral polymerase, L protein. A quantitative analysis of the profile of viral RNA segments packaged into RVFV particles showed that all three genomic RNA segments had similar packaging abilities, whereas among antigenomic RNA segments, the antigenomic S RNA, which serves as the template for the transcription of mRNA expressing the RVFV virulence factor, NSs, displayed a significantly higher packaging ability. To delineate the factor(s) governing the packaging of RVFV RNA segments, we characterized the interactions between Gn and viral RNPs in RVFV-infected cells. Coimmunoprecipitation analysis demonstrated the interaction of Gn with N protein, L protein, and viral RNAs in RVFV-infected cells. Furthermore, UV-cross-linking and immunoprecipitation analysis revealed, for the first time in bunyaviruses, the presence of a direct interaction between Gn and all the viral RNA segments in RVFV-infected cells. Notably, analysis of the ability of Gn to bind to RVFV RNA segments indicated a positive correlation with their respective packaging abilities and highlighted a binding preference of Gn for antigenomic S RNA, among the antigenomic RNA segments, suggesting the presence of a selection mechanism for antigenomic S RNA incorporation into infectious RVFV particles. Collectively, the results of our study illuminate the importance of a direct interaction between Gn and viral RNA segments in determining their efficiency of incorporation into RVFV particles.IMPORTANCERift Valley fever phlebovirus, a bunyavirus, is a mosquito-borne, segmented RNA virus that can cause severe disease in humans and ruminants. An essential step in RVFV life cycle is the packaging of viral RNA segments to produce infectious virus particles for dissemination to new hosts. However, there are key gaps in knowledge regarding the mechanisms that regulate viral RNA packaging efficiency in bunyaviruses. Our studies investigating the mechanism of RNA packaging in RVFV revealed the presence of a direct interaction between the viral envelope glycoprotein, Gn, and the viral RNA segments in infected cells, for the first time in bunyaviruses. Furthermore, our data strongly indicate a critical role for the direct interaction between Gn and viral RNAs in determining the efficiency of incorporation of viral RNA segments into RVFV particles. Clarifying the fundamental mechanisms of RNA packaging in RVFV would be valuable for the development of antivirals and live-attenuated vaccines.