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: 10490440
• 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/10490440
• 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虫媒病毒疾病，每年感染人数高达 4 亿，死亡人数达 25,000 人。相关的黄病毒寨卡病毒（ZIKV）也已在热带和亚热带地区迅速传播，DENV 和 ZIKV 感染的疫情现已蔓延至美国大陆。目前还没有针对这两种病毒的有效抗病毒药物，没有批准在美国使用的 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病毒感染所需的细胞途径，因为这些可能代表抗病毒治疗的新靶标。我们和其他人已经确定了宿主内质网膜蛋白复合物（EMC）是多种黄病毒（包括 DENV 和 ZIKV）感染所需的。 EMC 似乎起到分子伴侣的作用，促进内质网中多通道膜蛋白的生物发生。然而，EMC 如何支持黄病毒感染尚不清楚。引人注目的是，我们发表的研究结果表明，在感染过程中，EMC 是黄病毒复制所必需的，通过在翻译后早期步骤促进黄病毒 NS4A 和 NS4B 的生物发生。这两种蛋白都是病毒复制所必需的非结构性多次跨膜蛋白。该提案的目标是定义 EMC 如何支持 DENV 和 ZIKV 复制。基于强有力的初步数据，我们的中心假设是，EMC 作为分子伴侣，促进选定的黄病毒编码的多次跨膜蛋白的正确生物发生。该提案利用了一位在黄病毒宿主生物学方面拥有丰富经验的研究者 (Tai) 和另一位在病毒感染期间劫持的 ER 质量控制机制 (Tsai) 方面的互补优势。该项目的具体目标是 (1) 定义并验证 EMC 依赖性的病毒决定因素； (2)确定EMC在黄病毒复制中的具体作用； (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 支持黄病毒感染的机制，从而深入了解这些医学上重要的病毒所共有的新漏洞。它还将增加我们对需要 EMC 的其他病毒的了解。