Overcoming host Genetic Redundancy and Pathogen Subversion to Define new host-viral Interfaces

项目摘要/摘要 病毒已经进化出复杂的机制来劫持宿主的细胞机器。对于他们来说， 东道主已经开发出了自己复杂的防御系统。定义这些对立的策略是如何 共同进化增加了我们对传染病的了解，并提供了新的机会 发现生物学中未被探索的领域。我们对宿主细胞防御系统的理解是 由于宿主基因组中的遗传冗余，这一点是有限的。另一个复杂的问题是，成功的病原体 能够在感染期间使宿主的抗病毒网络失活。我们最近建立了一个新的 克服这些障碍的基因筛查平台。首先，我们绕过了基因冗余 通过识别抗病毒基因的功能筛选获得宿主基因组。第二，我们两个都用 我们筛选流水线中的强毒和弱毒病毒株。重要的是，这些衰减 病毒具有关键的免疫逃避蛋白的缺失或突变，但人们对此知之甚少 拮抗宿主抗病毒限制因子。我们预测这些病毒的无毒株将 对限制因素变得敏感，否则这些限制因素就会阻碍分子鉴定。使用这个 战略，其中一个项目将是识别古老的抗病毒基因，揭示宿主未被认识的区域- 病原体冲突。例如，我们正在揭开流感免疫逃避蛋白NS1是如何 使用对比屏幕和 野生型和NS1缺陷病毒。我们正在将这些研究扩展到其他毒力减弱的病毒 配对也是如此。另一个项目是利用新发现的抗病毒分子来抑制不同的病毒 并定义了抑制病毒的分子机制。在这里，我们将重点放在玉石上 组蛋白乙酰化调节组蛋白家族。我们的目标是揭示 Jade家族，并确定它是否组装了一个协调的抗病毒表观遗传程序。另一个项目 是利用新发现的宿主-病原体冲突来发现宿主的生理功能- 鲜为人知的蛋白质。在这方面，我们的重点是CD300受体家族 蛋白质。CD300基因正在经历快速的正选择，但它们的生理功能仍然存在 很大程度上是未被开发的。我们先前证明CD300lf是小鼠诺如病毒的蛋白受体。 我们将使用我们开发的生化、遗传和细胞工具来研究诺如病毒-CD300。 相互作用以定义CD300受体的生理配体。确定这些化合物的配体 孤儿受体将提供对这些快速进化的蛋白质的功能洞察。总而言之，我们 绘制发现新的宿主-病原体界面的路线图，定义它们的分子相互作用 在宿主防御过程中，以及这与这些蛋白质和途径的生理功能之间的关系。

Project Summary/Abstract Viruses have evolved sophisticated mechanisms to hijack host cellular machinery. For their part, hosts have developed their own intricate defense systems. Defining how these opposing strategies have co-evolved increases our understanding of infectious diseases and provides new opportunities to discover unexplored areas of biology. Our understanding of host cellular defense systems has been limited due to genetic redundancy in host genomes. A further complication is that successful pathogens are able to inactivate host antiviral networks during infection. We have recently established a new genetic screening platform that overcomes these roadblocks. First, we bypass genetic redundancy in host genomes through a gain of function screen that identifies antiviral genes. Second, we use both virulent and attenuated strains of viruses in our screening pipeline. Importantly, these attenuated viruses have deletions or mutations in critical, yet poorly understood, immune evasion proteins that antagonize host antiviral restriction factors. We predict that the avirulent strains of these viruses will become sensitive to restriction factors that have otherwise defied molecular identification. Using this strategy, one project will be to identify ancient antiviral genes that reveal unappreciated areas of host- pathogen conflict. For example, we are unmasking how the influenza immune evasion protein, NS1 orchestrates a complex, multifaceted rewiring of host antiviral networks using comparative screens with wild-type and NS1-deficient viruses. We are extending these studies to other virulent-attenuated virus pairings as well. Another project takes newly identified antiviral molecules that inhibit disparate virus families and define the molecular mechanism underlying viral inhibition. Here, we focus on the JADE family of proteins that regulate histone acetylation. We aim to uncover functional redundancy in the JADE family and to determine if it assembles a concerted antiviral epigenetic program. Another project is to leverage newly identified host-pathogen conflicts to discover the physiological functions of host- proteins that are poorly understood. In this regard, we are focusing on the CD300 family of receptor proteins. CD300 genes are undergoing rapid positive selection, yet their physiological function remains largely unexplored. We previously demonstrated that CD300lf is a protein receptor for murine norovirus. We will employ the biochemical, genetic, and cellular tools we developed for studying norovirus-CD300 interactions to define the physiological ligands of CD300 receptors. Determining the ligands for these orphan receptors will provide functional insight into these rapidly evolving proteins. Taken together, we plot a road map for discovering new host-pathogen interfaces, defining their molecular interactions during host defense, and how this relates to the physiological functions of these proteins and pathways.