Inhibition of viral entry by interferon-induced proteins

干扰素诱导蛋白抑制病毒进入

基本信息

批准号：
10418696
负责人：
Gregory B Melikian
金额：
$ 35.6万
依托单位：
EMORY UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2018
资助国家：
美国
起止时间：
2018-07-01 至 2024-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10418696
关键词：
Acute Affect Animal Model Antiviral Response Binding Proteins Biological Assay Biophysics Biosensor Cell Culture Techniques Cell membrane Cells Cellular biology Chemicals Chimera organism Competence Data Dengue Dimerization Ebola Electrons Endosomes Exhibits Future IFITM1 gene Image Imaging Device Imaging Techniques Infection Infection prevention Influenza Influenza A virus Integral Membrane Protein Integration Host Factors Interferons Label Laboratories Lassa virus Link Lipids Measures Mechanics Mediating Membrane Microscopy Modeling Modulus Murine leukemia virus Pathway interactions Phenotype Phosphatidylinositols Phosphoric Monoester Hydrolases Positioning Attribute Property Protein Family Proteins Publishing Reporting Resistance Resolution Role SARS coronavirus Severe Acute Respiratory Syndrome Site Technical Expertise Testing Time Transmembrane Transport VAPA gene Vesicle Viral Virus Visualization West Nile virus endosome membrane experimental study fluidity human pathogen in vivo innovation insight late endosome light microscopy lipid metabolism mechanical properties member novel novel virus particle protein distribution protein expression protein transport recruit trafficking virology virus envelope

项目摘要

Interferon-inducible transmembrane proteins (IFITMs) exhibit broad antiviral activity, both in cell culture and in vivo. IFITM expression has been shown to prevent infection of important human pathogens, including influenza, Ebola, West Nile and SARS viruses, by blocking viral fusion with target cells. The existence of IFITM-resistant viruses, such as Murine Leukemia and Lassa viruses, suggests that restriction occurs in a cellular compartment- specific manner. The mechanism by which fusion of diverse viruses is inhibited by IFITMs and the escape mechanisms from IFITM restriction are not understood, due in part to difficulties associated with visualization of their dynamic distribution in living cells. We made and validated functional fluorescently-tagged IFITM proteins and imaged, for the first time, single virus/IFITM co-trafficking and fusion. Pilot experiments suggest that viruses that co-traffic with IFITMs are trapped at a hemifusion stage, unable to form a fusion pore, whereas resistant viruses appear to be transported through endosomes devoid of IFITMs. We also discovered a novel role for phosphoinositides in viral fusion and the IFITM restriction phenotype. Our working hypothesis is that IFITMs block virus entry by: (i) trapping viral fusion at a dead-end hemifusion stage through by altering the properties of cell membranes; and (ii) favoring non-productive fusion with intralumenal vesicles within enlarged multivesicular compartments. We will test the working hypothesis using a panel of validated IFITM-sensitive and –resistant pseudoviruses and a powerful combination of virology, cell biology, membranebiophysics and advanced imaging techniques. Specifically, we will: (1) elucidate whether dynamic colocalization of IFITMs with viruses is a prerequisite for restriction; (2) determine whether IFITMs inhibit viral fusion by altering the mechanical properties of cell membranes that disfavor the transition from hemifusion to full fusion and/or through diverting the virus entry to a non-productive pathway; and (3) delineate the role of phosphoinositides in the IFITM restriction phenotype. Insights into the mechanism of IFITM-mediated virus restriction will provide important clues on how cells mount efficient antiviral responses and suggest new strategies for preventing infection.

干扰素诱导的跨膜蛋白（IFITM）暴露于细胞培养和中体内。 IFITM表达已被证明可以防止感染重要的人类病原体，包括影响力，埃博拉病毒，西尼罗河和SARS病毒通过阻断与靶细胞的病毒融合。抗IFITM的存在病毒，例如鼠白血病和LASSA病毒，表明限制发生在细胞室中 - 具体方式。 IFITM和逃生抑制潜水病毒融合的机制尚不清楚来自IFITM限制的机制，部分原因是与可视化的可视化相关性它们在活细胞中的动态分布。我们制作并验证了功能性荧光标记的IFITM蛋白并首次对单个病毒/IFITM进行成像。试验实验表明病毒与IFITM的同时人交通被困在半置阶段，无法形成融合孔，而抗性病毒似乎是通过缺乏IFITM的内体运输的。我们还发现了一个新颖的角色病毒融合和IFITM限制表型中的磷酸肌醇。我们的工作假设是通过：（i）通过更改特性，通过以下细胞膜；（ii）在增加的多细胞中，支持与量身内蔬菜的非生产性融合车厢。我们将使用一组经过验证的IFITM敏感和耐药性测试工作假设伪病毒以及病毒学，细胞生物学，膜生物物理学和高级成像的强大组合技术。具体而言，我们将：（1）阐明IFITM与病毒的动态共定位是否为一个限制的先决条件；（2）确定IFITS是否通过改变机械性能抑制病毒融合不利于从半分裂到完全融合和/或通过转移病毒的过渡的细胞膜进入非生产途径；（3）描述磷酸肌醇在IFITM限制中的作用表型。对IFITM介导的病毒限制机制的见解将为如何提供有关如何的重要线索细胞安装有效的抗病毒反应，并提出预防感染的新策略。