Mechanism of viral RNP recognition by the envelope glycoprotein and its role in RNA segment packaging in Rift Valley Fever phlebovirus

裂谷热白蛉病毒包膜糖蛋白识别病毒RNP的机制及其在RNA片段包装中的作用

• 批准号: 10057583
• 负责人: Shinji Makino
• 金额: $ 23.7万
• 依托单位: UNIVERSITY OF TEXAS MED BR GALVESTON
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-06-10 至 2022-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10057583
• 关键词: Africa; Africa South of the Sahara; Agriculture; Animals; Antiviral Agents; Antiviral Response; Attenuated Live Virus Vaccine; Binding Sites; Biological; Biological Assay; Bioterrorism; Bunyaviridae; Categories; Cattle; Cells; Centers for Disease Control and Prevention (U.S.); Code; Country; Culicidae; Cytoplasm; Cytoplasmic Tail; Data; Development; Disease; Disease Outbreaks; Domestic Animals; Economics; Elements; Encephalitis; Endemic Diseases; Epidemic; Evolution; Gene Expression; General Population; Genome; Genomics; Genus Phlebovirus; Glycoproteins; Goals; Golgi Apparatus; Human; Immune response; Infection; Innate Immune Response; Interferons; Knowledge; Life Cycle Stages; Livestock; Mediating; Messenger RNA; Movement; National Institute of Allergy and Infectious Disease; Nonstructural Protein; North America; Nucleocapsid Proteins; Panic; Patients; Population; Production; Proteins; Public Health; RNA; RNA Viruses; RNA chemical synthesis; RNA-Directed RNA Polymerase; Reagent; Regulation; Research; Retina; Retinal Vasculitis; Ribonucleoproteins; Rift Valley Fever; Role; Ruminants; Sheep; Signal Transduction; Structure; System; Testing; Translating; Vaccines; Viral; Viral Genome; Viral Hemorrhagic Fevers; Viral Packaging; Viral Pathogenesis; Virion; Virulence Factors; Virus; Virus Assembly; Virus Replication; Visual impairment; design; economic impact; genomic RNA; insight; macula; mosquito-borne; mutant; novel; particle; pathogen; programs; transmission process; vector; viral RNA; viral genomics

Rift Valley fever Phlebovirus (RVFV), a bunyavirus, belongs to the NIAID Category A list of pathogens and the CDC list of potential bioterrorism agents. RVFV causes a disease that is endemic in sub-Saharan Africa and can emerge in explosive, mosquito-borne epidemics that decimate herds of sheep and cattle, resulting in enormous economic losses. In humans, RVFV infection may cause hemorrhagic fever, encephalitis, and retinal vasculitis. Many different mosquitoes, including several species native to North America, are competent vectors for RVFV transmission. The introduction of RVFV into North America would likely cause panic in the general population, and the effects on livestock could have a devastating economic impact. The lack of availability of licensed vaccines or anti-RVFV reagents for use in humans or domestic animals is of great concern. RVFV carries a tripartite, single-stranded, negative-sense RNA genome, including L RNA encoding L protein, M RNA encoding two major envelope glycoproteins, Gn and Gc, and S RNA encoding N and NSs. NSs is the major virulence factor that efficiently suppresses host antiviral responses. The S RNA uses an ambi-sense strategy for gene expression; NSs is translated from the mRNA that is transcribed from the antigenomic-sense S RNA, whereas N protein is produced from the mRNA that is transcribed from the genomic-sense S RNA. One of the essential steps in virus replication and dissemination is the packaging of viral genome into virus particles, however, the mechanisms of viral RNA packaging in RVFV and other bunyaviruses are largely unknown. Insight into the underlying rules and mechanisms that govern the packaging of viral RNA genome into RVFV particles is valuable for understanding the regulation of virus replication, virus evolution, and the pathogenesis of the virus. This knowledge is also critical for the development of antiviral drugs that can inhibit infectious virus production or for the development of a live- attenuated vaccine strain. We propose that a direct interaction of Gn with the viral RNA segments is the primary factor that influences the packaging efficiencies of viral RNAs into RVFV particles. The present application will clarify the mechanism and biological significance of efficient packaging of antigenomic S RNA into virus particles by characterizing the direct interaction of Gn with antigenomic S RNA, identify the Gn- binding sites in viral RNAs, and examine the importance of antigenomic S RNA packaging for RVFV replication. The data obtained from the proposed studies will clarify the fundamental mechanisms that drive viral RNA packaging in RVFV and other bunyaviruses, with the overall goal of informing the design of novel antivirals and vaccines.

裂谷热白蛉病毒 (RVFV) 是一种布尼亚病毒，属于 NIAID A 类病原体清单和 CDC 潜在生物恐怖主义制剂清单。裂谷热病毒引起的疾病在撒哈拉以南非洲地区流行，并可能以蚊子传播的爆炸性流行病的形式出现，导致羊群和牛群大量死亡，造成巨大的经济损失。在人类中，RVFV 感染可能导致出血热、脑炎和视网膜血管炎。许多不同的蚊子，包括原产于北美的几种蚊子，都是裂谷热病毒传播的有效媒介。裂谷热病毒传入北美可能会引起普通民众的恐慌，而对牲畜的影响可能会造成毁灭性的经济影响。缺乏用于人类或家畜的许可疫苗或抗RVFV试剂令人非常担忧。 RVFV携带三部分、单链、负义RNA基因组，包括编码L蛋白的L RNA、编码两种主要包膜糖蛋白Gn和Gc的M RNA以及编码N和NS的S RNA。 NSs 是有效抑制宿主抗病毒反应的主要毒力因子。 S RNA 使用双义策略进行基因表达； NS 是由反基因组正义 S RNA 转录的 mRNA 翻译而来，而 N 蛋白是由基因组正义 S RNA 转录的 mRNA 产生。病毒复制和传播的重要步骤之一是将病毒基因组包装到病毒颗粒中，然而，RVFV和其他布尼亚病毒中病毒RNA包装的机制很大程度上未知。深入了解控制病毒RNA基因组包装成RVFV颗粒的基本规则和机制对于理解病毒复制、病毒进化和病毒发病机制的调控具有重要意义。这些知识对于开发能够抑制传染性病毒产生的抗病毒药物或开发减毒活疫苗株也至关重要。我们认为 Gn 与病毒 RNA 片段的直接相互作用是影响病毒 RNA 包装成 RVFV 颗粒的效率的主要因素。本申请将通过表征Gn与反基因组S RNA的直接相互作用，阐明反基因组S RNA有效包装到病毒颗粒中的机制和生物学意义，鉴定病毒RNA中的Gn结合位点，并检验反基因组S RNA的重要性用于 RVFV 复制的包装。从拟议研究中获得的数据将阐明驱动 RVFV 和其他布尼亚病毒中病毒 RNA 包装的基本机制，总体目标是为新型抗病毒药物和疫苗的设计提供信息。