Flavivirus non-coding RNAs and the Host mRNA Decay Machinery

黄病毒非编码 RNA 和宿主 mRNA 衰变机制

• 批准号: 9238132
• 负责人: Jeffrey Wilusz
• 金额: $ 37.09万
• 依托单位: COLORADO STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-09-28 至 2021-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9238132
• 关键词: 3' Untranslated Regions; 5' Untranslated Regions; Biological; Bovine Viral Diarrhea Viruses; Cataloging; Catalogs; Cell Line; Cells; Cellular Structures; Complex; Cytopathology; Data; Dengue Virus; Detection; Digestion; Disease; Elements; Enzymes; Exonuclease; Exoribonucleases; Family; Feedback; Flaviviridae; Flavivirus; Flavivirus Infections; Foundations; Gene Expression; Gene Expression Process; Goals; Hepatitis C virus; Hepatitis C-Like Viruses; Human; Indium; Infection; Insecta; Internal Ribosome Entry Site; Laboratories; Mammalian Cell; Maps; Mediating; Messenger RNA; MicroRNAs; Molecular; Nature; Pathway interactions; Play; Poly A; Process; Property; Publishing; Quality Control; RNA; RNA Decay; RNA Degradation; RNA Viruses; Regulation; Repression; Research Design; Role; Series; Structure; Testing; Transcript; Transcription Initiation Site; Untranslated RNA; Untranslated Regions; Viral; Viral Pathogenesis; Virus; Virus Replication; West Nile virus; Work; Zika Virus; cell growth regulation; genome-wide; inhibitor/antagonist; insight; mRNA Decay; mRNA Stability; member; novel; novel strategies; pathogen; poly A specific exoribonuclease; polyadenylated messenger RNA; research study; transcriptome; tumorigenesis; viral RNA; virus host interaction

The Flaviviridae are a family of positive-sense RNA viruses that contain numerous important human pathogens. Many of the molecular mechanisms that underlie how these RNA viruses cause cytopathology and disease are not clearly described. The cellular mRNA decay machinery, in particularly the 5'-3' pathway mediated by the exoribonuclease Xrn1, plays a major role in regulating the abundance and quality of gene expression in the cell. Understudied, but nevertheless very important aspects of flavivirus-host interactions, include how viral RNAs are protected from degradation by the cellular mRNA decay machinery and what are the implications of the viral RNA stabilization strategies on the regulation of cellular mRNA stability. We have recently observed that flaviviruses repress the activity of Xrn1 through trapping the enzyme using unique structured regions of the viral RNA. Interestingly, it is the 5' UTR IRES region that is responsible for this Xrn1 repression in Hepatitis C virus and Bovine Viral Diarrhea virus. These observations serve as the foundation for this proposal to gain in-depth mechanistic insights into molecular mechanisms of Xrn1 repression and regulation that are disrupted by flavivirus RNAs. In Aim 1, we will identify the sequence/structural requirements of IRES-mediated Xrn1 repression and determine whether this is a common property of other viral IRES elements. The goal of Aim 2 is understand at a mechanistic level why the repression of Xrn1 by flavivirus RNAs results in the apparent shut down of the entire 5'-3' mRNA decay pathway – not just the exonucleolytic digestion step. Uncovering the interplay and feedback regulation of the decay factors in the 5'-3' RNA decay pathway will provide novel insights into how the cell normally regulates this decay pathway and integrate it into the overall process of gene expression. In the third aim we will expand our studies on Xrn1 stalling and investigate whether it is an approach used by the cell to remodel cellular transcripts. In the final Aim, we will characterize key biological aspects of Xrn1 repression from the perspective of both the cell and the virus. A key focus of this part will be on the dysregulation of cellular mRNA stability by flaviviruses that results in dramatic changes in cellular gene expression that could play a significant role in HCV-mediated oncogenesis.

Flaviviridae是一个阳性RNA病毒的家族，其中包含许多重要人类 病原体。这些RNA病毒如何引起细胞病理学的许多分子机制 和疾病未清楚地描述。细胞mRNA衰变机械，特别是5'-3'途径 由Exoriboncleplease XRN1介导，在调节基因的抽象和质量中起着重要作用 在细胞中的表达。研究了Flavivirus-Host相互作用的非常重要的方面，但 包括如何保护病毒RNA免受细胞mRNA衰变机械的降解，什么是 病毒RNA稳定策略对细胞mRNA稳定性调节的影响。我们有 最近观察到，黄病毒通过使用独特的酶捕获酶来反映XRN1的活性 病毒RNA的结构化区域。有趣的是，是该XRN1负责的5'UTR IRES地区 丙型肝炎病毒和牛病毒腹泻病毒的抑制。这些观察是 这项提出的建议是对XRN1表达和分子机制的深入机械见解和 FLAVIVIRUS RNA破坏的调节。在AIM 1中，我们将确定序列/结构要求 IRES介导的XRN1表达的表达，并确定这是否是其他病毒IRES的共同特性 元素。 AIM 2的目标是在机械级别上理解为什么Flavivivirus XRN1的表达 RNA导致整个5'-3'mRNA衰减途径的明显关闭 - 不仅仅是核解核解液 消化步骤。发现5'-3'RNA衰减中衰减因子的相互作用和反馈调节 途径将为细胞正常调节该衰减途径的方式提供新的见解并将其整合到 基因表达的总体过程。在第三个目标中，我们将扩大有关XRN1失速的研究和 研究这是否是细胞用于重塑细胞转录本的方法。在最终目标中，我们将 从细胞和病毒的角度来表征XRN1表达的关键生物学方面。一个 该部分的关键重点将是通过黄病毒导致细胞mRNA稳定性的失调 细胞基因表达的急剧变化，可能在HCV介导的肿瘤发生中起重要作用。