Viral and cellular mechanisms of HSV fusion and entry

HSV融合和进入的病毒和细胞机制

• 批准号: 10673420
• 负责人: ANTHONY V NICOLA
• 金额: $ 37.4万
• 依托单位: WASHINGTON STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-05-15 至 2024-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10673420
• 关键词: Address; Biochemistry; Biological Assay; Blindness; Cell Culture Techniques; Cell fusion; Cell surface; Cells; Cellular biology; Chimeric Proteins; Clinical; Complex; Data; Defect; Development; Disease; Encephalitis; Endosomes; Epithelial Cells; Experimental Designs; Glycoproteins; Goals; Heparan Sulfate Proteoglycan; Heparitin Sulfate; Herpes Labialis; Herpesviridae; Herpesviridae Infections; Herpesvirus 1; Human; Immunocompromised Host; In Vitro; Infection; Integration Host Factors; Intervention; Knowledge; Laboratories; Lytic Phase; Mammalian Cell; Maps; Mediating; Mediator of activation protein; Membrane Fusion; Membrane Glycoproteins; Modeling; Molecular; Molecular Conformation; Molecular Virology; Morbidity - disease rate; Nature; Neonatal; Neurons; Outcome; PVRL1; Pathway interactions; Penetration; Play; Prevention; Process; Proteins; Recurrence; Regulation; Research; Role; Sexually Transmitted Diseases; Shapes; Simplexvirus; Site; Specificity; Structure; Surface; Techniques; Testing; Therapeutic; Time; Vaccines; Viral; Viral Envelope Proteins; Virus; Virus Diseases; Virus-Cell Membrane Interaction; antibody detection; cell type; env Gene Products; genital infection; human pathogen; inhibiting antibody; inhibitor; innovation; insight; latent infection; mortality; neonatal infection; novel; novel strategies; pathogen; prevent; receptor

Herpesviruses are ubiquitous pathogens that cause significant morbidity and mortality worldwide. Herpes simplex virus (HSV) causes cold sores and sexually transmitted infections. Grave outcomes of HSV infection include neonatal disease, blindness, and disseminated infections of the immunocompromised. Our long-term goal is a comprehensive understanding of the entry mechanisms of this important group of pathogens. Although much progress has been made, the complex mechanisms of herpesvirus fusion and entry remain enigmatic. This has posed a roadblock to developing clinically effective entry inhibitors. HSV enters most cultured mammalian cells and commandeers diverse entry pathways. An emerging concept in herpesvirology is that endosomal pH of the host cell is required for viral entry, often in a cell type specific manner. However, the mechanistic role that low pH plays in herpesviral entry is not clear. The HSV envelope proteins gB, gD, and the gH/gL heterodimer are required but are likely not sufficient for membrane fusion and entry in the context of HSV infection. Envelope protein gC is the principal mediator of viral attachment to cell surface heparan sulfate proteoglycans during entry. However, this interaction is dispensable for viral entry in cell culture and does not explain the infection defect of gC-deleted viruses. We recently revealed a new, post-attachment function for gC in HSV entry. gC influences the fusion protein gB and promotes efficient penetration of HSV from endosomes during entry. gC elevates the pH-threshold of fusion- associated conformational changes in the fusion protein gB. We formulated complementary yet independent aims to delineate previously unrecognized functions of HSV-1 gC. In Specific Aim 1, we will elucidate gC's role in fusion and entry by employing a battery of assays in the context of the required HSV envelope proteins and cellular receptors. Specific Aim 2 encompasses structure-function studies of gC pertinent to entry and infection of epithelial cells, the main target of primary and recurrent HSV infection. Our experimental design employs techniques of cell biology, biochemistry, and molecular virology. Completion of the aims will reveal detailed insight into the multifunctional nature of HSV-1 gC and will fill critical knowledge gaps about how the complex fusion mechanism of herpesviruses is triggered in pathophysiologically relevant cell types. These studies will aid in the development of new preventions and therapeutics for HSV.

疱疹病毒是无处不在的病原体，在全球范围内引起大量发病率和死亡率。单纯疱疹病毒（HSV）会引起唇疱疹和性传播感染。 HSV感染的严重结局包括新生儿疾病，失明和免疫功能低下的传播感染。我们的长期目标是对这一重要病原体的进入机制的全面理解。尽管取得了很大的进展，但疱疹病毒融合和进入的复杂机制仍然是神秘的。这为开发临床有效的进入抑制剂带来了障碍。 HSV进入大多数培养的哺乳动物细胞和指挥官各种入口途径。疱疹病毒学中的一个新兴概念是，宿主细胞的内体pH是病毒细胞所必需的，通常是特定于细胞类型的方式。但是，低pH值在疱疹病毒进入中的机械作用尚不清楚。需要HSV包膜蛋白GB，GD和GH/GL异二聚体，但在HSV感染的背景下可能不足以进行膜融合和进入。包膜蛋白GC是进入细胞表面硫酸盐蛋白聚糖的主要介体。然而，这种相互作用对于细胞培养的病毒进入是可分配的，并且不能解释GC缺失病毒的感染缺陷。我们最近透露了HSV条目中GC的新的，后连接功能。 GC会影响融合蛋白GB，并在进入过程中促进HSV从内体中有效渗透。 GC提高了融合蛋白GB中融合相关构象变化的pH阈值。我们制定了互补而独立的旨在描述HSV-1 GC的先前未识别功能。在特定目标1中，我们将在所需的HSV包膜蛋白和细胞受体的背景下使用一系列测定法，阐明GC在融合和进入中的作用。具体目标2涵盖了与上皮细胞的进入和感染有关的GC的结构 - 功能研究，这是原发性和复发性HSV感染的主要靶标。我们的实验设计采用细胞生物学，生物化学和分子病毒学技术。目标的完成将揭示对HSV-1 GC多功能性质的详细见解，并将填补有关如何在病理生理相关的细胞类型中触发疱疹病毒的复杂融合机制的关键知识差距。这些研究将有助于开发HSV的新预防和治疗剂。