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

基本信息

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
项目类别：
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&apos Untranslated Regions 5&apos 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

项目摘要

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.

黄病毒科是一类正义 RNA 病毒，含有许多重要的人类病毒。这些 RNA 病毒如何引起细胞病理学的许多分子机制。细胞 mRNA 降解机制，特别是 5'-3' 途径尚未明确描述。由核糖核酸外切酶 Xrn1 介导，在调节基因的丰度和质量中起主要作用细胞中的表达尚未得到充分研究，但仍然是黄病毒与宿主相互作用的非常重要的方面，包括如何保护病毒 RNA 免受细胞 mRNA 降解机制的降解，以及什么是病毒 RNA 稳定策略对细胞 mRNA 稳定性调节的影响。最近观察到黄病毒通过使用独特的捕获酶来抑制 Xrn1 的活性病毒RNA的结构区域暗示，5'UTR IRES区域负责这个Xrn1。这些观察结果为丙型肝炎病毒和牛病毒性腹泻病毒的抑制奠定了基础。该提案旨在深入了解 Xrn1 抑制的分子机制在目标 1 中，我们将确定被黄病毒 RNA 破坏的序列/结构要求。 IRES 介导的 Xrn1 抑制，并确定这是否是其他病毒 IRES 的共同特性目标 2 的目标是从机制层面理解为什么黄病毒会抑制 Xrn1。 RNA 导致整个 5'-3' mRNA 衰变途径明显关闭——而不仅仅是核酸外切途径揭示 5'-3' RNA 衰变中衰变因子的相互作用和反馈调节。途径将为细胞如何正常调节这种衰变途径并将其整合到在第三个目标中，我们将扩展对 Xrn1 停滞和基因表达的整体过程的研究。研究它是否是细胞用来重塑细胞转录本的方法。从细胞和病毒的角度描述 Xrn1 抑制的关键生物学方面。这一部分的重点是黄病毒对细胞 mRNA 稳定性的失调，从而导致细胞基因表达的巨大变化可能在 HCV 介导的肿瘤发生中发挥重要作用。