Novel Translational Control Mechanisms in Host Range Restriction of Poxvirus

痘病毒宿主范围限制的新型翻译控制机制

• 批准号: 10463680
• 负责人: Junpeng Deng
• 金额: $ 42.24万
• 依托单位: UNIVERSITY OF TEXAS HLTH SCIENCE CENTER
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-09-22 至 2025-08-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10463680
• 关键词: Address; Binding; Codon Nucleotides; Complex; Crystallization; DNA; DNA Binding; DNA Binding Domain; Dangerousness; Data; Development; Genes; Genetic Variation; Host Defense; Human Genome; Immune response; Infection; Interferons; Knock-out; Knowledge; Mammalian Cell; Mediating; Modeling; Molecular; Orthopoxvirus; Pathway interactions; Pattern recognition receptor; Peptide Initiation Factors; Phenylalanine; Play; Poxviridae; Process; Protein Biosynthesis; Proteins; Regulation; Resistance; Ribosomal RNA; Ribosomes; Rodent; Role; Signal Transduction; Species Specificity; Specificity; Structure; Transfection; Transfer RNA; Translation Initiation; Translations; Vaccinia virus; Viral; Viral Pathogenesis; Virus; Virus Diseases; antagonist; antiviral drug development; arms race; cellular targeting; cytosolic receptor; ds-DNA; emerging pathogen; experimental study; genome-wide; inhibitor; insight; novel; overexpression; poxvirus vectors; pressure; response; ribosome profiling; tRNA Methyltransferases; transcriptome sequencing; vector vaccine

All viruses rely on host translational machinery for protein synthesis. As such, translation control constitutes a universal host defense against viruses. A new understanding on how host regulates translation in response to viral infection and how viruses evade this host response will provide fundamental insight into viral pathogenesis and benefit the development of new antiviral strategies. Poxviruses include some dangerous emerging pathogens as well as some promising vaccine vectors. Unlike many other viruses, poxvirus host range is not affected by the entry step but restricted by intracellular processes. Particularly, cellular translational control pathways have a profound impact on poxvirus host range, and poxvirus inhibitors of these pathways could manifest as critical host-range factors. The best-known example is PKR-mediated control of translation initiation and its antagonism by two vaccinia virus (VACV) host-range proteins E3 and K3. Much less is understood about a PKR-independent pathway targeted by two critical VACV host-range proteins, K1 and C7. VACV with deletion in both K1 and C7 fails to replicate in most mammalian cells due to a shut-off of viral and host protein synthesis. Intriguingly, the translational shut-off is independent of PKR and RNaseL and appears not to involve any translation initiation factors. A paralogous pair of interferon-stimulated genes, SAMD9 and SAMD9L (SAMD9&L), were recently identified by us and others as the specific targets of K1 and C7. However, how they regulate protein synthesis and restrict poxvirus host range is unknown and is the focus of this proposal. We have made sustained contributions to the understanding of K1/C7 and their cellular targets for over a decade, including the determination of the structures of K1/C7 and the identification of SAMD9L as a cellular target of K1/C7. In addition, we have obtained compelling preliminary data that led to our novel hypotheses, which will be addressed separately with the following specific aims. Aim 1. To determine how SAMD9 is activated to inhibit protein synthesis. Aim 2. To determine how activated SAMD9 inhibits protein synthesis. Aim 3. To determine the molecular basis underlying the host species-specific SAMD9&L inhibition by OPXV inhibitors.

所有病毒都依赖宿主翻译机制来合成蛋白质。因此，翻译 控制构成了宿主对病毒的普遍防御。对如何主持的新认识 调节对病毒感染的反应以及病毒如何逃避宿主反应的翻译 提供对病毒发病机制的基本见解并有利于新型抗病毒药物的开发 策略。 痘病毒包括一些危险的新兴病原体以及一些有前途的疫苗 向量。与许多其他病毒不同，痘病毒的宿主范围不受进入步骤的影响，但 受细胞内过程的限制。特别是，细胞翻译控制途径具有 对痘病毒宿主范围产生深远影响，这些途径的痘病毒抑制剂可以 表现为关键的宿主范围因素。最著名的例子是 PKR 介导的控制 两种牛痘病毒 (VACV) 宿主范围蛋白 E3 的翻译起始及其拮抗作用 和K3。对于两个关键靶点的 PKR 独立通路了解甚少。 VACV 宿主范围蛋白、K1 和 C7。 K1 和 C7 均缺失的 VACV 无法复制 在大多数哺乳动物细胞中，由于病毒和宿主蛋白质合成的关闭。有趣的是， 翻译关闭独立于 PKR 和 RNaseL，并且似乎不涉及任何 翻译起始因素。一对旁系同源干扰素刺激基因 SAMD9 和 SAMD9L (SAMD9&L)，最近被我们和其他人确定为 K1 的具体目标 和C7。然而，它们如何调节蛋白质合成并限制痘病毒宿主范围尚不清楚。 未知，也是本提案的重点。 我们为了解 K1/C7 及其细胞做出了持续的贡献 十多年来的目标，包括K1/C7结构的确定和 鉴定 SAMD9L 作为 K1/C7 的细胞靶标。此外，我们还获得了令人信服的 初步数据导致了我们的新假设，这些假设将与 遵循特定目标。 目标 1. 确定 SAMD9 如何被激活以抑制蛋白质合成。 目标 2. 确定激活的 SAMD9 如何抑制蛋白质合成。 目标 3. 确定宿主物种特异性 SAMD9&L 的分子基础 OPXV 抑制剂的抑制作用。