Stress granules in virus infections

病毒感染中的应激颗粒

• 批准号: 10578897
• 负责人: Malathi Krishnamurthy
• 金额: $ 49.01万
• 依托单位: UNIVERSITY OF TOLEDO
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-01-01 至 2025-12-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10578897
• 关键词: Antiviral Response; Binding; Biochemical; Cells; Cellular Stress; Complex; Cytoplasm; Double-Stranded RNA; Drug Targeting; Ebola virus VP35 protein; Encephalomyocarditis virus; Endoribonucleases; Endosomes; Eukaryotic Initiation Factors; Event; Future; G3BP1 gene; Immune response; Immune signaling; Infection; Innate Immune Response; Interferons; Knock-out; Ligands; Ligase; Messenger RNA; Methods; Molecular; Mutagenesis; Nature; Outcome; Oxidative Stress; Pathway interactions; Pattern; Pattern recognition receptor; Phase; Phosphorylation; Physiological; Production; Protein Kinase; Proteins; Proteomics; RNA; RNA-Binding Proteins; Resistance; Ribonucleases; Role; Signal Pathway; Signal Transduction; Stimulus; Stress; Stress Tests; Testing; Time; Toll-like receptors; Transfection; Translations; Viral; Viral Pathogenesis; Viral Proteins; Virus; Virus Diseases; Work; biological adaptation to stress; drug development; experimental study; helicase; mutant; new therapeutic target; novel; oligoadenylate; pathogen; protein protein interaction; receptor; recruit; response; stress granule; transcriptomics; translation factor; undergraduate research; undergraduate student; virus host interaction

Stress granules (SG) are non-membranous, phase-separated complexes of stalled mRNA, translation factors and RNA binding proteins that are formed transiently in the cytoplasm in response to diverse stress signals, including viral infections. SG formed during viral infection, antiviral stress granules (avSG), are distinct from canonical SG in that they recruit antiviral proteins and components of signaling pathways to function as a platform to mount an effective antiviral response. However, the composition, temporal changes and function of avSG during viral infections are still poorly understood. The dynamic nature of SG suggest that host cells use avSG as a signaling hub for antiviral defense. On the other hand, viruses have evolved mechanisms to antagonize SG formation and repurpose SG to facilitate replication highlighting an important role in viral pathogenesis. How the stress-specific differences in SG composition, assembly and dynamics impact the outcome of viral infections remains unclear and represents a critical gap in our understanding of signaling events and host-virus interactions. Our recent work has highlighted a role for avSG as a platform for the activation of pattern recognition receptors (PRRs) by dsRNA pathogen associated molecular patterns (PAMPs) and subsequent interferon (IFN) response during viral infections. DsRNAs produced during viral infections serve as PAMPs to stimulate interferon (IFN) production by binding the cytosolic Rig-like helicases (RLHs), endosomal Toll-like receptors (TLRs), dsRNA-dependent protein kinase (PKR) or 2’-5’oligoadenylate synthetase (OAS). Furthermore, virus infection induces degradation of viral and cellular RNAs by the activity of interferon-induced endoribonuclease, RNase L. We have recently shown that dsRNA products of RNase L activity function as PAMPs and activate PKR, phosphorylate eukaryotic translation initiation factor-2 (eIF2) to suppress translation and induce avSG formation. Our results demonstrate that avSG assembly provides a platform for efficient interaction of RNA ligands with PRRs to enhance interferon production and antiviral effect. Our overarching hypothesis for this proposal is that composition, assembly and disassembly of avSG change during viral infection to allow host cells to respond and clear infection by limiting damage. In preliminary studies we show that activation of RNase L induces avSG formation marked by SG protein, G3BP1 and contain antiviral proteins Rig-I, PKR, OAS and RNase L. We developed a novel method to purify avSG and biochemically characterized protein-protein interactions in avSG that will be used in this proposal. We will test our central hypothesis with the following specific aims. Aim 1: To determine stress-specific differences in SG composition in canonical SG and avSG, Aim 2: To determine the physiological role of dynamic change in avSG composition in virus infections. Completion of these aims will allow us to build on the advances in purifying avSG to dissect the antiviral role of SG by following the dynamics of assembly or disassembly and analyzing the avSG composition to provide correlation of stress response pathways and innate signaling.

应力颗粒（SG）是停滞mRNA的非月相分离的复合物，翻译因子 和RNA结合蛋白，这些蛋白在细胞质中瞬时形成，以响应于潜水的应激信号， 包括病毒感染。在病毒感染期间形成的SG，抗病毒应激颗粒（AVSG）与 规范SG是因为它们募集抗病毒蛋白和信号通路的成分，以充当 安装有效抗病毒反应的平台。但是，组成，临时变化和功能 病毒感染期间的AVSG仍然很少了解。 SG的动态性质表明宿主细胞使用 AVSG作为抗病毒防御的信号枢纽。另一方面，病毒已经发展到 拮抗SG形成并复制SG，以促进复制突出在病毒中的重要作用 发病。 SG组成，组装和动态的应力特异性差异如何影响 病毒感染的结果尚不清楚，这代表了我们对 信号事件和主机病毒相互作用。我们最近的工作强调了AVSG作为平台的角色 用于通过DSRNA病原体相关的分子模式激活模式识别受体（PRR） （PAMP）和随后的干扰素（IFN）在病毒感染过程中反应。病毒期间产生的dsrNA 感染是通过结合胞质钻机样解旋酶来刺激干扰素（IFN）产生的小型弹药 （RLHS），内体收费受体（TLR），DSRNA依赖性蛋白激酶（PKR）或2'-5'-5'oligoadenylate 合成酶（OAS）。此外，病毒感染通过活性诱导病毒和细胞RNA降解 干扰素诱导的内核酸酶RNase L.我们最近表明RNase L的DsRNA产物 活性功能充当pamps并激活PKR，磷酸化真核翻译起始因子-2（EIF2） 抑制翻译并诱导AVSG形成。我们的结果表明，AVSG大会提供了 RNA配体与PRR有效相互作用的平台以增强干扰产生和抗病毒作用。 我们对该提议的总体假设是AVSG的组成，组装和拆卸 病毒感染期间的变化，使宿主细胞通过限制损害做出反应和清除感染。在 初步研究我们表明，RNase L的激活诱导SG蛋白标记的AVSG形成G3BP1 并包含抗病毒蛋白RIG-I，PKR，OAS和RNaseL。我们开发了一种新的方法来净化AVSG 在此提案中将使用的AVSG中蛋白质 - 蛋白质相互作用具有生化特征的蛋白质 - 蛋白质相互作用。我们将 通过以下特定目的测试我们的中心假设。目标1：确定应力特异性差异 典型SG和AVSG中的SG组成，目标2：确定动态变化的物理作用 病毒感染中的AVSG组成。这些目标的完成将使我们能够在进步的基础上建立 纯化AVSG通过遵循组装或拆卸的动态来剖析SG的抗病毒作用 分析AVSG组成，以提供应力响应途径和先天信号的相关性。