Influenza virus host shutoff mechanism

流感病毒宿主关闭机制

• 批准号: 10237177
• 负责人: TORU TAKIMOTO
• 金额: $ 38.5万
• 依托单位: UNIVERSITY OF ROCHESTER
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-09-25 至 2023-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10237177
• 关键词: Affect; Antiviral Agents; Attention; Attenuated; Attenuated Vaccines; Baculoviruses; Biological Assay; C-terminal; Cell Nucleus; Cells; Cleavage And Polyadenylation Specificity Factor; Cytoplasm; Data; Elements; Eukaryotic Initiation Factors; Foundations; Gene Expression; Growth; Host Defense Mechanism; Human; Immune Evasion; Immune response; In Vitro; Inflammation; Inflammatory; Influenza A Virus, H1N1 Subtype; Influenza A virus; Innate Immune Response; Integration Host Factors; Learning; Location; Lung; Mass Spectrum Analysis; Mediating; Messenger RNA; Molecular; Mutation; Nuclear Export; Open Reading Frames; Outcome; Pathogenicity; Play; Poly(A)-Binding Proteins; Polynucleotide Adenylyltransferase; Protein Analysis; Protein Biosynthesis; Proteins; RNA Polymerase II; Reporting; Research; Ribosomal Frameshifting; Ribosomes; Role; Safety; Site; System; Testing; Transcript; Translating; Translations; Vaccines; Viral; Viral Genes; Viral Proteins; Virus; Virus Diseases; Virus Replication; base; comparative; cytokine; endonuclease; improved; in vivo; influenzavirus; mRNA Precursor; mRNA Transcript Degradation; mouse model; mutant; novel; overexpression; pandemic disease; prevent; protective efficacy; protein expression; recombinant virus; response; vaccine efficacy

Virus infection induces a wide range of host defense mechanisms, such as the innate immune response and inflammation. Some viruses express accessory proteins to induce general shutoff of host protein synthesis, which is considered to be one of the major viral strategies to counteract host antiviral activity and immune response. Influenza A virus is one of these viruses and expresses two proteins NS1 and PA-X to induce host shutoff. PA-X is a novel protein found to be expressed from PA mRNA by ribosomal frameshifting. PA-X is composed of an endonuclease domain of PA with a unique C-terminal region. Recent studies including ours indicate that mRNA degradation is the major strategy for host shutoff. The PA-X is more active in shutoff activity than NS-1, and it contains multiple regions involved in specific mRNA degradation. Characterization of a mutant 2009 pandemic H1N1 virus expressing reduced amount of PA-X indicates that PA-X plays a significant role in antagonizing host innate and acquired immune responses. The mechanism of how PA-X induces shutoff is not known. However, a recent study showed that PA-X selectively degrades host RNA polymerase II transcripts, and that pre- mRNAs under 3’-processing are susceptible for PA-X degradation. We also found that PA-X localizes and degrades mRNAs in both the nucleus and cytoplasm, suggesting that PA-X has multiple strategies to capture and degrade pre-mRNAs and mature mRNAs in cells. This project will reveal the mechanism of how PA-X targets and degrades host pre-mRNA in the nucleus (Aim 1), and mature mRNAs in the cytoplasm (Aim 2). Using viruses having various shutoff activities, we will determine the functional interaction between PA-X and NS1 to unveil how IAV adjusts the level of shutoff to create optimum condition for viral replication. Because the shutoff activity directly affects host immune responses, we will test a hypothesis that efficacy of live attenuated vaccine can be improved by suppressing shutoff activity. Overall, the proposed study will provide a foundation for understanding 1) the mechanism by which influenza viruses modulate host gene expression, 2) the mechanism by which viral gene expression is optimized, and 3) the impact of PA-X on viral pathogenicity and host immune response. Upon completion of these studies, we will learn the unique multiple strategy of PA-X in inducing host shutoff in infected cells, and its impact on viral pathogenicity and immune evasion.

病毒感染诱导多种宿主防御机制，例如先天免疫 一些病毒表达辅助蛋白以诱导宿主的全面关闭。 蛋白质合成，被认为是抵抗宿主抗病毒的主要病毒策略之一 甲型流感病毒是其中一种病毒，表达两种蛋白质。 NS1 和 PA-X 诱导宿主关闭 PA-X 是一种由 PA mRNA 表达的新型蛋白质。 PA-X 是由具有独特 C 末端的 PA 核酸内切酶结构域组成。 最近的研究（包括我们的研究）表明 mRNA 降解是宿主的主要策略。 PA-X 的关闭活动比 NS-1 更活跃，并且它包含多个涉及的区域。 2009 年大流行 H1N1 病毒表达突变体的特异 mRNA 降解特征。 PA-X 量的减少表明 PA-X 在拮抗宿主先天和 然而，PA-X 如何引起关闭的机制尚不清楚。 最近的研究表明，PA-X 选择性降解宿主 RNA 聚合酶 II 转录本，并且预 3'-加工下的 mRNA 很容易被 PA-X 降解。我们还发现 PA-X 定位。 并降解细胞核和细胞质中的 mRNA，表明 PA-X 具有多种策略 捕获并降解细胞中的前体 mRNA 和成熟 mRNA，该项目将揭示其机制。 PA-X 如何靶向并降解细胞核中的宿主前 mRNA（目标 1）以及细胞核中的成熟 mRNA 细胞质（目标 2）。使用具有各种关闭活性的病毒，我们将确定其功能。 PA-X 和 NS1 之间的交互揭示了 IAV 如何调整关闭级别以创造最佳效果 因为关闭活性直接影响宿主的免疫反应，所以我们 将检验一个假设，即可以通过抑制关闭来提高减毒活疫苗的功效 总体而言，拟议的研究将为理解 1）机制奠定基础。 哪些流感病毒调节宿主基因表达，2）病毒基因调节宿主基因表达的机制 表达得到优化，3) PA-X 对病毒致病性和宿主免疫反应的影响。 完成这些研究后，我们将了解 PA-X 诱导宿主的独特多重策略 受感染细胞的关闭及其对病毒致病性和免疫逃避的影响。

项目成果

Key Role of the Influenza A Virus PA Gene Segment in the Emergence of Pandemic Viruses.

甲型流感病毒 PA 基因片段在大流行病毒出现中的关键作用。

• 发表时间: 2020
• 作者: Lutz Iv, Michael M;Dunagan, Megan M;Kurebayashi, Yuki;Takimoto, Toru
• 通讯作者: Takimoto, Toru

Impact of Influenza A Virus Shutoff Proteins on Host Immune Responses.

甲型流感病毒关闭蛋白对宿主免疫反应的影响。

• 发表时间: 2021-06-10
• 影响因子: 7.8
• 作者: Dunagan, Megan M;Hardy, Kala;Takimoto, Toru
• 通讯作者: Takimoto, Toru

Pharmacologic profiling reveals lapatinib as a novel antiviral against SARS-CoV-2 in vitro.

药理学分析表明拉帕替尼是一种新型体外抗 SARS-CoV-2 病毒药物。

• 发表时间: 2022-01
• 影响因子: 3.7
• 作者: Raymonda, M H;Ciesla, J H;Monaghan, M;Leach, J;Asantewaa, G;Smorodintsev;Lutz 4th, M M;Schafer, X L;Takimoto, T;Dewhurst, S;Munger, J;Harris, I S
• 通讯作者: Harris, I S

Specificity and functional interplay between influenza virus PA-X and NS1 shutoff activity.

流感病毒 PA-X 和 NS1 关闭活性之间的特异性和功能相互作用。

• 发表时间: 2018
• 影响因子: 6.7
• 作者: Chaimayo, Chutikarn;Dunagan, Megan;Hayashi, Tsuyoshi;Santoso, Netty;Takimoto, Toru
• 通讯作者: Takimoto, Toru

Safety and immunogenicity of an intranasal sendai virus-based vaccine for human parainfluenza virus type I and respiratory syncytial virus (SeVRSV) in adults.

基于鼻内仙台病毒的成人 I 型副流感病毒和呼吸道合胞病毒 (SeVRSV) 疫苗的安全性和免疫原性。

• 发表时间: 2021-02-01
• 影响因子: 4.8
• 作者: Scaggs Huang, Felicia;Bernstein, David I;Slobod, Karen S;Portner, Allen;Takimoto, Toru;Russell, Charles J;Meagher, Michael;Jones, Bart G;Sealy, Robert E;Coleclough, Christopher;Branum, Kristen;Dickey, Michelle;Buschle, Kristen;McNeal, Monica
• 通讯作者: McNeal, Monica