Functional characterisation of the molecular interactome of emerging viral haemorrhagic fever arenaviruses

新兴病毒性出血热沙粒病毒分子相互作用组的功能特征

• 批准号: 2432890
• 金额: --
• 依托单位: University of Nottingham
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2020
• 资助国家: 英国
• 起止时间: 2020 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2432890
• 关键词: Functional; characterisation; molecular; interactome; emerging

The recent Ebola and Lassa fever epidemics highlight the immense impact human viral haemorrhagic fevers (VHFs) have on human health and on the socio-economic status of the developing world. Arenaviruses are the largest family of VHF-causing viruses; they have worldwide distribution and are endemic in South America and West Africa, mainly in Sierra Leone, Liberia and Nigeria. The current outbreak by the most common arenavirus, Lassa, in Nigeria, makes it imperative to understand the molecular basis of viral pathogenesis and immune evasion, to identify factors that drive viral emergence and to identify drug targets.The Arenaviridae family is divided into Old World (OW - endemic in West Africa) and New World (NW - endemic in South America) viruses based on their phylogeny, geographical distribution and serological cross reactivity. Arenaviruses cause persistent infections in their natural rodent hosts and viral transmission to humans occurs through direct contact with infectious materials or exposure to rodent urine/faeces. Fatality rates are extremely high; there is no vaccine and the few therapeutic options are ineffective. The overarching aim is to map the complex pathways that are responsible for potentiating and antagonising arenavirus infection and, importantly, explore the molecular basis of host adaptation.Despite possessing a small genome and encoding for only 4 proteins, arenaviruses have developed strategies to maintain high levels of replication and avoid host immune responses, implying multiple viral and host protein interactions. Thus far, few host cell protein interactions have been identified.Current knowledge of the modulation of immune factors is restricted to the viral nucleoprotein (NP) and matrix protein (Z) and their inhibition of type I interferon (IFN) induction. Given, the involvement of these proteins in early to late steps of the viral life cycle, it is unlikely that their immunosuppressive function is exclusively limited to this mechanism. Furthermore, they possess structural characteristics that could be fundamental to their ability to modulate different viral processes central to viral spread.In order to unravel the arenavirus interactome and the differential mechanisms between OW and NW viruses, the student will aim to:1) develop proteomic screens for the identification of novel interacting partners of NP and Z. Developing these methods will reveal novel co-factors that define pathogenicity differences. Mutational analysis of NP and Z will inform experiments that can delineate differential mechanisms used by pathogenic and non-pathogenic viral strains. Validation of identified protein interactors will involve CRISPR/Cas9 knockout and CAT4 virus assays conducted via collaboration in Marburg. Linked to this will be the use of structural methods, i.e. X-ray crystallography and NMR, to 2) elucidate the molecular details of the interactions of NP and Z with host factors; exploiting these interactions is key in the application of this research to the design of therapeutics. Structural information will define the molecular details of novel host interactions and will inform the future design of effective therapeutics. NP and Z are highly amenable for structural studies and interactions revealed in Aim 1 will be exploited to obtain protein complex structures.References to learn more:1. Zapata, J.C.; Salvato, M.S. (2013) Arenavirus Variations Due to Host-Specific Adaptation. Viruses 5, 241-278.2. Yun, N.E.; Walker, D.H. (2012) Pathogenesis of Lassa Fever. Viruses 4, 2031-2048

最近的埃博拉和拉沙热疫情突出了人类病毒性出血热对人类健康和发展中世界社会经济地位的巨大影响。阿拉伯病毒是引起VHF的最大病毒家族；它们在世界各地分布，在南美洲和西非流行，主要在塞拉利昂、利比里亚和尼日利亚。目前尼日利亚最常见的沙门氏菌病毒Lassa的暴发使得了解病毒致病和免疫逃避的分子基础，确定驱动病毒出现的因素和确定药物靶点变得至关重要。根据病毒的系统发生、地理分布和血清学交叉反应，Arenaviridae家族分为旧世界(西非特有的)和新世界(南美洲特有的)病毒。禽流感病毒在其自然啮齿动物宿主中引起持续感染，病毒通过直接接触传染病物质或接触啮齿动物的尿液/粪便传播给人类。死亡率极高；没有疫苗，为数不多的治疗选择无效。总体目标是绘制负责增强和拮抗ArenaVirus感染的复杂途径，重要的是探索宿主适应的分子基础。ArenaVirus虽然拥有较小的基因组，仅编码4种蛋白质，但它们已经制定了保持高水平复制和避免宿主免疫反应的策略，这意味着病毒和宿主蛋白的多重相互作用。目前对免疫因子的调节作用仅限于病毒核蛋白(NP)和基质蛋白(Z)及其对I型干扰素(干扰素)诱导的抑制作用。鉴于这些蛋白参与了病毒生命周期的早期和后期，它们的免疫抑制功能不太可能仅限于这一机制。此外，它们具有的结构特征可能是它们调控病毒传播中心不同病毒过程的基础。为了揭开ArenaVirus的相互作用组以及OW和NW病毒之间的差异机制，学生的目标是：1)开发蛋白质组筛选，用于鉴定NP和Z的新的相互作用伙伴。开发这些方法将揭示定义致病性差异的新的辅助因素。对NP和Z的突变分析将为描述致病和非致病病毒株所使用的不同机制的实验提供信息。已确定的蛋白质相互作用的验证将涉及通过在马尔堡合作进行的CRISPR/Cas9基因敲除和CAT4病毒检测。与此相关的是使用结构方法，即X射线结晶学和核磁共振，以2)阐明NP和Z与宿主因子相互作用的分子细节；利用这些相互作用是将这项研究应用于治疗设计的关键。结构信息将定义新的宿主相互作用的分子细节，并将为未来有效疗法的设计提供信息。NP和Z非常适合结构研究，目标1中揭示的相互作用将被用来获得蛋白质复杂结构。参考文献：1.Zapata，J.C.；Salato，M.S.(2013)由于宿主特异性适应而导致的病毒变异。病毒5,241-278.2。云，N.E.；沃克，D.H.(2012)拉沙热的发病机制。病毒4,2031-2048