RNA-Binding Proteins and Host Shut-Off by VSV

RNA 结合蛋白和 VSV 关闭宿主

• 批准号: 9020822
• 负责人: DOUGLAS S. LYLES
• 金额: $ 43.56万
• 依托单位: WAKE FOREST UNIVERSITY HEALTH SCIENCES
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-03-01 至 2019-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9020822
• 关键词: Address; Affect; Antiviral Response; Attenuated; Binding; Cell Nucleus; Cells; Chemicals; Chromatin; Complex; Cytoplasm; Data; Defective Viruses; Development; Disease; Employee Strikes; Gene Expression; Genes; Genetic; Genetic Transcription; Genetic Translation; Goals; Health; High-Throughput Nucleotide Sequencing; Homebound Persons; Human; Immunoblotting; Immunoprecipitation; Integration Host Factors; Laboratories; Malignant Neoplasms; Messenger RNA; Molecular; Nuclear; Nuclear Envelope; Nuclear Pore Complex Proteins; Nuclear RNA; Pathogenicity; Process; Proteins; Proteomics; RNA Interference; RNA Transport; RNA-Binding Proteins; Rhabdoviridae; Ribonucleoproteins; Role; Testing; Translating; Translations; Vaccines; Vesicular stomatitis Indiana virus; Viral; Viral Genes; Viral Matrix Proteins; Viral Proteins; Virus; Virus Assembly; Virus Diseases; Work; base; cellular targeting; chromatin immunoprecipitation; crosslink; inhibitor/antagonist; messenger ribonucleoprotein; multiple myeloma M Protein; mutant; novel; novel virus; particle; prototype; research study

DESCRIPTION (provided by applicant): Many viruses suppress host antiviral responses through the global inhibition of host gene expression, often referred to as "host shut-off". Vesicular stomatitis virus (VSV), the prototype rhabdovirus, is a well-established example of a virus that suppresses antiviral responses through the global inhibition of host gene expression. The host shut-off in VSV-infected cells is particularly extensive, resulting in the inhibition of hst transcription, nuclear-cytoplasmic transport of host mRNA, and translation of host proteins. The work of our laboratory and others has shown that the VSV matrix (M) protein is the major inhibitor of host gene expression in VSV-infected cells, and that the ability of M protein to inhibt host gene expression is genetically separable from its function in virus assembly. The goal of this project is to determine how a relatively small (229 a.a.) protein can have such a profound effect on host gene expression. M protein appears to inhibit host gene expression by binding to host components and interfering with their function. Thus far the only host component identified that binds to M protein and not to mutant M proteins is the RNA-binding protein Rae1. Rae1 is a multifunctional protein that was originally thought to be involved in mRNA transport. However, our recent experiments have shown that the M protein-Rae1 complex in VSV-infected cells primarily inhibits host transcription. Furthermore, silencing Rae1 expression has no effect on nuclear accumulation of host mRNAs induced by VSV infection, demonstrating that the block in their transport is independent of Rae1 expression. Finally, our data indicate that the inhibition o translation by VSV is a downstream effect of the inhibition of transcription, thus raising the question of how the virus counters this inhibition in order for viral mRNAs to be translated. The stimulation of translation of viral mRNAs appears to be due to an activity of M protein that is independent of its host shut-off function and involves novel assembly of ribonucleoprotein particles (RNP) that promote translation. The mechanisms by which M protein affects these three levels of gene expression will be determined according to the following aims: 1) Determine the mechanism by which M protein-Rae1 complexes inhibit host transcription. 2) Determine the role of host RNA-binding proteins in mRNA transport in VSV-infected cells. 3) Determine the role of M protein and host RNA-binding proteins in promoting the selective translation of viral mRNAs in VSV-infected cells. These experiments will use state-of-the-art chromatin and RNP immunoprecipitation approaches combined with high throughput sequencing to analyze host and viral gene expression in cells infected with well-characterized M protein mutants or cells in which expression of key host factors is suppressed by RNA silencing. These experiments should reveal novel mechanisms by which VSV inhibits host gene expression. In addition, they should provide novel information about how cellular RNA-binding proteins like Rae1 can regulate host transcription, and how networks of RNA-binding proteins can control translation that is applicable to other viruses that suppress antiviral responses by the global inhibition of host transcription and RNA transport.

描述（由申请人提供）：许多病毒通过全球抑制宿主基因表达来抑制宿主抗病毒反应，通常称为“宿主关闭”。原型色齿病毒（VSV）是囊泡口腔炎病毒（VSV），是一个公认的病毒的例子，该病毒通过全局抑制宿主基因表达来抑制抗病毒反应。 VSV感染细胞中的宿主关闭特别广泛，导致抑制HST转录，宿主mRNA的核胞质转运和宿主蛋白的翻译。我们实验室和其他实验室的工作表明，VSV基质（M）蛋白是VSV感染细胞中宿主基因表达的主要抑制剂，并且M蛋白抑制宿主基因表达的能力在遗传上与其在病毒组装中的功能上可分开。该项目的目的是确定相对较小的（229 a.A.）蛋白如何对宿主基因表达产生如此深远的影响。 M蛋白似乎通过与宿主成分结合并干扰其功能来抑制宿主基因的表达。迄今为止，唯一确定与M蛋白结合而不是突变M蛋白结合的宿主成分是RNA结合蛋白RAE1。 RAE1是一种多功能蛋白，最初被认为与mRNA转运有关。但是，我们最近的实验表明，VSV感染细胞中的M蛋白-RAE1复合物主要抑制宿主转录。此外，沉默的RAE1表达对VSV感染诱导的宿主mRNA的核积累没有影响，这表明其运输中的块与RAE1表达无关。最后，我们的数据表明，VSV的抑制作用O翻译是转录抑制的下游效应，因此提出了一个问题，即病毒如何反驳这种抑制以使病毒mRNA被翻译。刺激病毒mRNA的翻译似乎是由于M蛋白的活性独立于其宿主关闭功能，并且涉及促进翻译的核糖核蛋白颗粒（RNP）的新型组装。 M蛋白会根据以下目的确定M蛋白影响这三个基因表达的机制：1）确定M蛋白-RAE1复合物抑制宿主转录的机制。 2）确定宿主RNA结合蛋白在VSV感染细胞中mRNA转运中的作用。 3）确定M蛋白和宿主RNA结合蛋白在促进VSV感染细胞中病毒mRNA的选择性翻译中的作用。这些实验将使用最先进的染色质和RNP免疫沉淀方法与高吞吐量测序结合来分析宿主和病毒基因表达，并在感染了特征良好的M蛋白突变体或细胞感染的细胞中，其中关键宿主因子的表达被RNA沉默抑制了关键的宿主因子。这些实验应揭示VSV抑制宿主基因表达的新型机制。此外，他们应提供有关细胞RNA结合蛋白（例如RAE1）如何调节宿主转录的新信息，以及RNA结合蛋白网络如何控制适用于通过全局抑制宿主转录和RNA转运的其他病毒的翻译。