Membrane fusion during HSV-1 entry

HSV-1 进入期间的膜融合

• 批准号: 7843510
• 负责人: Robert James Geraghty
• 金额: $ 7.55万
• 依托单位: UNIVERSITY OF MINNESOTA
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-05-15 至 2012-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7843510
• 关键词: Address; Binding; Cell fusion; Cell membrane; Cell surface; Cells; Data; Endocytosis; Endosomes; Event; Glycoproteins; Goals; Herpesviridae; Herpesvirus 1; Lipid Bilayers; Location; Measures; Mediating; Membrane; Membrane Fusion; Methods; Modeling; Molecular; Process; Proteins; Research; Route; Simplexvirus; Site; Testing; Virus; design; inhibitor/antagonist; late endosome; novel; public health relevance; receptor binding; receptor mediated endocytosis; research study

DESCRIPTION (provided by applicant): Herpes simplex virus (HSV), and likely all herpesviruses, use two methods to enter cells: (1) direct fusion: the virus fuses its lipid bilayer with the plasma membrane at the cell surface and (2) receptor-mediated endocytosis (RME): the virus fuses with an endosomal membrane after endocytosis and a reduction in pH. Our long-term goal is to understand the molecular events occurring during HSV-1-induced membrane fusion for both direct fusion and RME. We have recently identified a fusion intermediate (hemifusion) during virus-to- cell fusion for HSV-1. This is the first description of a fusion intermediate for any herpesvirus or any virus that uses more than two proteins to mediate membrane fusion. Our preliminary data are consistent with hemifusion occurring at the cell surface in cells that require endocytosis and low pH for HSV-1 entry. The focus of this application is to examine membrane fusion in our newly proposed model for herpesvirus RME. A unique aspect of this model is the proposed cell-surface location of the hemifusion event. We outline experiments here to establish the cellular location of hemifusion during HSV-1 RME by co- localizing the site of hemifusion with cellular markers. We will also use pharmacological agents that block endocytosis and endosomal pH reduction to determine if those processes are required for hemifusion to occur. Because herpesvirus entry occurs at the cell surface at neutral pH and is postulated to occur at the low pH of a late endosome, a testable prediction is that the HSV-1 fusion machinery must function at both neutral and low pH. To test that prediction, we will examine HSV-1 membrane fusion at low pH and compare it to that at neutral pH. The results obtained from this application will establish a model for HSV-1 RME. A detailed understanding of membrane fusion induced during direct fusion and RME is necessary to facilitate the design of inhibitors to block hemifusion, full fusion, and virus spread. PUBLIC HEALTH RELEVANCE: The aim of this project is to characterize the membrane fusion events during herpes simplex virus type 1 (HSV-1) entry into cells via receptor-mediated endocytosis. HSV-1 enters cells by multiple routes so the intricate understanding of the mechanism of each route is required to facilitate the design of anti-virals to block virus entry and spread.

DESCRIPTION (provided by applicant): Herpes simplex virus (HSV), and likely all herpesviruses, use two methods to enter cells: (1) direct fusion: the virus fuses its lipid bilayer with the plasma membrane at the cell surface and (2) receptor-mediated endocytosis (RME): the virus fuses with an endosomal membrane after endocytosis and a reduction in pH.我们的长期目标是了解直接融合和RME在HSV-1诱导的膜融合过程中发生的分子事件。我们最近确定了HSV-1病毒至细胞融合期间的融合中间体（半裂）。这是对任何疱疹病毒或任何使用两个以上蛋白质介导膜融合的病毒的融合中间体的第一个描述。我们的初步数据与需要内吞作用的细胞表面上的半分解和HSV-1进入的pH值低。该应用的重点是在我们新提出的疱疹病毒RME模型中检查膜融合。该模型的一个独特方面是半分类事件的拟议的细胞表面位置。我们在这里概述了在HSV-1 RME期间建立半分解的细胞位置，通过将半分解部位与细胞标记进行定位。我们还将使用阻断内吞作用和降低内体pH的药理剂来确定是否需要这些过程才能发生。由于疱疹病毒的进入在中性pH下发生在细胞表面，并假定在晚期内体的低pH值时发生，因此可检验的预测是HSV-1融合机械必须在中性和低pH值下起作用。为了测试该预测，我们将检查低pH值的HSV-1膜融合，并将其与中性pH进行比较。从本应用程序获得的结果将建立HSV-1 RME的模型。需要对直接融合和RME诱导的膜融合的详细理解，对于促进抑制剂的设计以阻断下半分泌，完全融合和病毒扩散。 公共卫生相关性：该项目的目的是表征单纯疱疹病毒1型（HSV-1）通过受体介导的内吞作用进入细胞的膜融合事件。 HSV-1通过多个路线进入细胞，因此需要对每种途径机理的复杂理解，以促进抗病毒的设计以阻止病毒进入和扩散。