Structural Mechanisms of Alphavirus Membrane Fusion

甲病毒膜融合的结构机制

基本信息

批准号：
10612929
负责人：
Wei Zhang
金额：
$ 38.85万
依托单位：
UNIVERSITY OF MINNESOTA
依托单位国家：
美国
项目类别：
财政年份：
2022
资助国家：
美国
起止时间：
2022-04-22 至 2027-03-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10612929
关键词：
Address Affect Alphavirus Antiviral Therapy Area Arthritis Back Biochemical Biochemistry Biological Assay Biological Models Biophysics Capsid Cells Cellular Membrane Centrifugation Chimeric Proteins Complex Cryo-electron tomography Cryoelectron Microscopy Cytoplasm Deposition Disease Disease Outbreaks Drops Early Endosome Economic Burden Encephalitis Endosomes Environment Equus caballus Event Flavivirus Glycoproteins Goals Human Human papillomavirus 16 E1 protein Image In Vitro Knowledge Length Licensing Lipid Bilayers Liposomes Mediating Membrane Membrane Fusion Membrane Lipids Methods Modeling Molecular Molecular Conformation Molecular Structure Mutagenesis Mutation Orthobunyavirus Process Proteins RNA Viruses Reaction Recurrence Research Rubella virus Sindbis Virus Site Structural Models Structural Protein Structure System Testing Vaccines Viral Viral Envelope Proteins Viral Genome Viral Proteins Virus Virus Assembly Virus Diseases Work antiviral drug development insight mutant novel prevent protein structure prototype receptor receptor mediated endocytosis recombinant virus uptake

项目摘要

Alphaviruses, a group of enveloped RNA viruses, cause persistent arthritis and encephalitis among horses and humans. Currently, no licensed vaccine or antiviral therapy is available to prevent or cure the disease. A critical step in enveloped virus infection is membrane fusion between the viral and the host cellular membranes, a process leading to cytoplasmic delivery of the viral genome. Alphaviruses enter the host cell via receptor- mediated endocytosis. The viral E1 protein mediates membrane fusion through conformational changes upon acidification in the early endosomes. The other viral envelope protein, E2, functions as a molecular chaperon for the E1 protein during virus assembly and plays a role in virus capsid core uptake at the budding site and release after membrane fusion. We have obtained exciting, unprecedented images that captured robust alphavirus membrane fusion events with target liposomes by cryo-electron microscopy. Using coordinated biochemical, biophysical, cryo-electron microscopy, and cryo-electron tomography methods, we will investigate the molecular structures of the E1 and E2 proteins in a prototype alphavirus, Sindbis virus, at specific fusion stages. We will test specific predictions about the alphavirus membrane fusion mechanism based on our structural results by generating and characterizing mutants of the glycoproteins. We will test the fusion function of key mutations in the context of recombinant viruses. Completing this research will advance our understanding about how alphavirus glycoproteins promote membrane fusion.

Alphaviruses是一组包裹的RNA病毒，在马和人类中引起持续性关节炎和脑炎。目前，尚无持牌疫苗或抗病毒疗法可预防或治愈该疾病。包围病毒感染的关键步骤是病毒和宿主细胞膜之间的膜融合，这是导致病毒基因组细胞质递送的过程。 α病毒通过受体介导的内吞作用进入宿主细胞。病毒E1蛋白通过早期内体酸化后构象变化介导膜融合。其他病毒包膜蛋白E2充当病毒组装过程中E1蛋白的分子伴侣，并在萌芽位点在病毒capsid核心摄取中起作用，并在膜融合后释放。我们获得了令人兴奋的，前所未有的图像，这些图像通过冷冻电子显微镜捕获了与靶脂质体的鲁棒膜融合事件。使用协调的生化，生物物理，冷冻电子显微镜和冷冻电子层析成像方法，我们将在特定融合阶段研究原型α和sindbis病毒中E1和E2蛋白的分子结构。我们将通过产生和表征糖蛋白突变体来测试有关α病毒膜融合机制的特定预测。我们将在重组病毒的背景下测试关键突变的融合功能。完成这项研究将提高我们对α病毒糖蛋白如何促进膜融合的理解。