How flaviviruses hijack a host transmembrane protein chaperone to promote viral infection

黄病毒如何劫持宿主跨膜蛋白伴侣以促进病毒感染

• 批准号: 10292571
• 负责人: Andrew W. Tai
• 金额: $ 35.61万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-09-20 至 2025-07-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10292571
• 关键词: Antiviral Agents; Arbovirus Infections; Biogenesis; Biology; Bypass; Cell physiology; Cells; Cessation of life; DNA; Data; Dengue Infection; Dengue Vaccine; Dengue Virus; Dependence; Disease Outbreaks; Endoplasmic Reticulum; Flavivirus; Flavivirus Infections; Goals; Human; Hydrophobicity; Infection; Integral Membrane Protein; Integration Host Factors; Maps; Medical; Membrane Proteins; Modeling; Molecular; Molecular Chaperones; Morbidity - disease rate; Mutation; Nonstructural Protein; Organelles; Pathway interactions; Polyomavirus; Protein-Folding Disease; Proteins; Publishing; Quality Control; Research Personnel; Rest; Role; Testing; United States; Vaccines; Viral; Viral Genome; Viral Proteins; Virus; Virus Diseases; Virus Replication; Yeasts; Yellow Fever; ZIKV infection; Zika Virus; Zika virus vaccine; base; experience; experimental study; insight; mortality; mosquito-borne pathogen; mutant; novel; novel strategies; protein complex; protein degradation; protein folding; virology

Dengue virus (DENV) infection is the most common arboviral disease globally, with up to 400 million infections and 25,000 deaths annually. The related flavivirus Zika virus (ZIKV) has also spread rapidly across the tropics and subtropics, and outbreaks of both DENV and ZIKV infection have now reached the continental United States. There are currently no effective antiviral agents against either virus, no DENV vaccine approved for use in the United States, and no ZIKV vaccine. Our long-term goal is to comprehensively identify and characterize the cellular pathways required for flavivirus infection, as these may represent novel targets for antiviral treatment. We and others have identified the host Endoplasmic Reticulum Membrane Protein Complex (EMC) as required for infection by multiple flaviviruses, including DENV and ZIKV. The EMC appears to function as a molecular chaperone, promoting the biogenesis of multipass membrane proteins in the endoplasmic reticulum. However, how the EMC supports flavivirus infection is unknown. Strikingly, our published findings reveal that during infection, the EMC is required by flavivirus replication by promoting the biogenesis of flavivirus NS4A and NS4B at an early post-translational step. Both proteins are non-structural multipass transmembrane proteins essential for viral replication. The objective of this proposal is to define how the EMC supports DENV and ZIKV replication. Our central hypothesis, based on strong preliminary data, is that the EMC functions as a molecular chaperone for the proper biogenesis of select flavivirus-encoded multipass transmembrane proteins. This proposal leverages the complementary strengths of an investigator with extensive experience in flavivirus-host biology (Tai), and another in ER-quality control mechanisms hijacked during viral infection (Tsai). The specific aims of the project are to (1) Define and validate the viral determinants of EMC dependence; (2) Determine the specific role of the EMC in flaviviral replication; and (3) Characterize DENV and ZIKV mutants that bypass EMC dependency. Successful completion of this project will illuminate the mechanism by which the EMC supports flavivirus infection, thereby providing insights into a novel vulnerability shared by these medically important viruses. It will also increase our understanding of other viruses that require the EMC.

登革热病毒（DENV）感染是全球最常见的丁香病毒疾病，每年多达4亿次感染和25,000例死亡。相关的黄病毒寨卡病毒（ZIKV）也迅速传播到热带和亚热带，DENV和ZIKV感染的爆发现已到达美国大陆。目前尚无针对任何一种病毒的有效抗病毒药，在美国批准了无DENV疫苗，也没有ZIKV疫苗。我们的长期目标是全面识别和表征黄素感染所需的细胞途径，因为这些可能代表了抗病毒药物治疗的新靶标。我们和其他人已经确定了多种黄病毒感染所需的宿主内质网膜蛋白复合物（EMC），包括DENV和ZIKV。 EMC似乎起着分子伴侣的作用，促进了内质网中多石膜蛋白的生物发生。但是，EMC如何支持黄病毒感染是未知的。引人注目的是，我们发表的发现表明，在感染期间，通过在翻译后早期促进Flavivivirus NS4A和NS4B的生物发生，需要通过黄病毒复制来进行EMC。两种蛋白质都是非结构性多层跨膜蛋白，对病毒复制必不可少。该建议的目的是定义EMC如何支持DENV和ZIKV复制。我们的中心假设基于强大的初步数据，是EMC充当分子伴侣，用于适当的精​​选黄病毒编码多通跨膜蛋白的适当生物发生。该提案利用了具有丰富的Flavivirus-Host生物学经验（TAI）的研究者的互补优势，而在病毒感染期间劫持了ER质量控制机制（TSAI）。该项目的具体目的是（1）定义和验证EMC依赖性的病毒决定因素； （2）确定EMC在黄病毒复制中的特定作用； （3）表征绕过EMC依赖性的DENV和ZIKV突变体。该项目的成功完成将阐明EMC支持黄素感染的机制，从而提供对这些医学重要病毒共享的新型脆弱性的见解。这也将增加我们对需要EMC的其他病毒的理解。