Interplay between coronaviruses and nonsense-mediated mRNA decay pathway

冠状病毒与无义介导的 mRNA 衰减途径之间的相互作用

• 批准号: 10358595
• 负责人: Shinji Makino
• 金额: $ 30.92万
• 依托单位: UNIVERSITY OF TEXAS MED BR GALVESTON
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-03-11 至 2024-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10358595
• 关键词: 3' Untranslated Regions; Address; Area; Attenuated; Binding; Binding Proteins; Biological; Biological Models; Biology; Cells; Clinical; Common Cold; Coronavirus; Coronavirus nucleocapsid protein; Country; Cytoplasm; Data; Development; Disease; Domestic Animals; Elements; Ensure; Epidemic; Europe; Exhibits; Far East; Gene Expression; Generations; Genetic Diseases; Genome; Host Defense Mechanism; Human; Introns; Knowledge; Lead; Measures; Mediating; Messenger RNA; Middle East; Middle East Respiratory Syndrome; Middle East Respiratory Syndrome Coronavirus; Molecular; Murine hepatitis virus; Nonsense-Mediated Decay; Northern Africa; Open Reading Frames; Pathogenicity; Pathway interactions; Phenotype; Phosphorylation; Physiological; Play; Post-Transcriptional Regulation; Predisposition; Proteins; Public Health; Quality Control; RNA; RNA Viruses; RNA-Binding Proteins; Research; Respiratory System; Role; SARS coronavirus; Saudi Arabia; Severe Acute Respiratory Syndrome; Structure; Symptoms; Terminator Codon; Testing; Therapeutic Agents; Time; Transcript; Vaccines; Viral; Viral Gene Expression Regulation; Viral Genes; Viral N Protein; Viral Proteins; Virus; Virus Assembly; Virus Replication; coronavirus vaccine; economic impact; endonuclease; gene product; human coronavirus; inhibitor; insight; mRNA Decay; mRNA Stability; mRNA Surveillance; mortality; mutant; novel; novel strategies; premature; prevent; recruit; respiratory; vaccine candidate; viral RNA; virology

Coronaviruses (CoVs), which carry a large, single-stranded, positive-sense RNA genome, cause a variety of diseases in humans and domestic animals. Human CoVs (HCoVs) usually infect the respiratory tract and cause a range of symptoms varying from mild, such as the common cold, to more serious respiratory illnesses like severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS), caused by two highly pathogenic HCoVs, SARS-CoV and MERS-CoV. SARS-CoV caused a worldwide epidemic in 2002- 2003, resulting in more than 8,000 cases with an approximate mortality of 10%, while MERS-CoV emerged in Saudi Arabia in 2012 and has been disseminated into other countries in the Middle East, North Africa, Europe, and East Asia. HCoVs represent a major threat to public health and have the potential to cause a significant negative economic impact. Currently, there are no approved vaccines and therapeutic agents against HCoVs. The development of effective control measures against CoVs requires a comprehensive understanding of viral gene expression strategies and host-CoV interactions. A plethora of studies have focused on investigating CoV biology and have significantly contributed to our understanding of CoV replication mechanisms, including the structure-function analyses of viral RNA elements as well as the viral proteins that are involved in viral replication and assembly. However, there are still gaps in our knowledge of the post-transcriptional regulation of viral gene expression, as only a limited number of studies have addressed this area of CoV research. Particularly, very little is known about the cis-acting viral RNA elements and trans-acting host and viral factors that regulate CoV mRNA transcript stability. One newly emerging research area in virology is understanding interactions between viruses and host mRNA surveillance pathways that prevent generation/accumulation of unwanted gene products. We have demonstrated that CoV mRNAs are the targets of the nonsense-mediated mRNA decay (NMD) pathway, one of the host mRNA surveillance pathways, and that viral N protein protects CoV mRNAs from NMD. Our data suggest the importance of N-mediated NMD suppression for efficient virus replication. The present application will study the interplay between the NMD pathway and CoVs by testing the following hypotheses: UPF1, the principal orchestrator of NMD, binds to the 3’ UTR of CoV mRNAs having specific motifs, undergoes phosphorylation, and recruits SMG6, an endonuclease, leading to endonucleolytic RNA cleavage; N binds to the 3’ UTRs of NMD targets and prevents an NMD factor(s) from accessing these targets and/or N interacts with an NMD factor(s) and sequesters it away from the NMD pathway; and CoV mutants having an increased susceptibility to NMD, cannot replicate as efficiently as the parental viruses. The data obtained from these studies will provide mechanistic insights into NMD of CoV mRNAs and N-mediated NMD pathway suppression, and will reveal the feasibility of novel strategies for attenuating CoVs through increased susceptibility to the NMD pathway.

冠状病毒 (CoV) 携带大型单链正链 RNA 基因组，可引起多种疾病 人类和家畜疾病。人类冠状病毒（HCoV）通常感染呼吸道并 引起一系列症状，从普通感冒等轻微症状到更严重的呼吸道疾病 例如严重急性呼吸系统综合症（SARS）和中东呼吸系统综合症（MERS），由两种疾病引起 高致病性 HCoV、SARS-CoV 和 MERS-CoV。 2002年，SARS-CoV在全球范围内引发流行病 2003 年，导致 8,000 多例病例，死亡率约为 10%，而 MERS-CoV 出现在 2012年在沙特阿拉伯上市，并已传播到中东、北非、欧洲等其他国家， 和东亚。 HCoV 对公共健康构成重大威胁，并有可能造成严重后果 负面经济影响。目前，尚无针对 HCoV 的批准疫苗和治疗药物。 制定针对冠状病毒的有效控制措施需要全面了解病毒 基因表达策略和宿主-冠状病毒相互作用。大量研究都集中在调查冠状病毒 生物学，并为我们对冠状病毒复制机制的理解做出了重大贡献，包括 病毒RNA元件以及参与病毒感染的病毒蛋白的结构功能分析 复制和组装。然而，我们对转录后调控的认识仍然存在差距。 病毒基因表达的研究，因为只有有限数量的研究涉及冠状病毒研究的这一领域。 特别是，对于顺式作用病毒RNA元件和反式作用宿主和病毒因子知之甚少 调节 CoV mRNA 转录稳定性。病毒学的一个新兴研究领域是了解 病毒和宿主 mRNA 监视途径之间的相互作用，防止产生/积累 不需要的基因产物。我们已经证明 CoV mRNA 是无义介导的靶标 mRNA 衰减 (NMD) 途径是宿主 mRNA 监视途径之一，病毒 N 蛋白可保护 来自 NMD 的 CoV mRNA。我们的数据表明 N 介导的 NMD 抑制对于有效病毒的重要性 复制。本申请将通过测试 NMD 途径和 CoV 之间的相互作用来研究 以下假设：UPF1 是 NMD 的主要协调者，与具有以下特征的 CoV mRNA 的 3’UTR 结合 特定基序，经历磷酸化，并招募 SMG6（一种核酸内切酶），导致核酸内切 RNA 切割； N 与 NMD 目标的 3' UTR 结合，并阻止 NMD 因子访问这些目标 目标和/或 N 与 NMD 因子相互作用并将其隔离于 NMD 途径；和冠状病毒 对 NMD 敏感性增加的突变体不能像亲代病毒那样有效地复制。这 从这些研究中获得的数据将为 CoV mRNA 的 NMD 和 N 介导的机制提供见解 NMD 通路抑制，并将揭示通过以下方式减弱 CoV 的新策略的可行性 对 NMD 途径的敏感性增加。