Membrane fusion during HSV-1 entry

HSV-1 进入期间的膜融合

• 批准号: 7447258
• 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 2011-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7447258
• 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.

描述（由申请人提供）：单纯疱疹病毒（HSV）以及可能的所有疱疹病毒使用两种方法进入细胞：（1）直接融合：病毒将其脂质双层与细胞表面的质膜融合；（2）受体介导的内吞作用（RME）：在内吞作用和pH降低后，病毒与内体膜融合。我们的长期目标是了解 HSV-1 诱导的直接融合和 RME 膜融合过程中发生的分子事件。我们最近在 HSV-1 病毒与细胞融合过程中发现了一种融合中间体（半融合）。这是对任何疱疹病毒或任何使用两种以上蛋白质介导膜融合的病毒的融合中间体的首次描述。我们的初步数据与 HSV-1 进入需要内吞作用和低 pH 值的细胞表面发生的半融合一致。本应用的重点是检查我们新提出的疱疹病毒 RME 模型中的膜融合。该模型的一个独特之处是所提出的半融合事件的细胞表面位置。我们在此概述了通过将半融合位点与细胞标记共定位来确定 HSV-1 RME 期间半融合的细胞位置的实验。我们还将使用阻断内吞作用和内体 pH 降低的药物来确定这些过程是否是半融合发生所必需的。由于疱疹病毒进入发生在中性 pH 值的细胞表面，并且假定发生在晚期内涵体的低 pH 值下，因此可测试的预测是 HSV-1 融合机制必须在中性和低 pH 值下都起作用。为了验证这一预测，我们将检查低 pH 条件下的 HSV-1 膜融合，并将其与中性 pH 条件下的膜融合进行比较。从该应用中获得的结果将建立 HSV-1 RME 模型。详细了解直接融合和 RME 过程中诱导的膜融合对于促进抑制剂的设计以阻止半融合、完全融合和病毒传播是必要的。 公共健康相关性：该项目的目的是表征 1 型单纯疱疹病毒 (HSV-1) 通过受体介导的内吞作用进入细胞期间的膜融合事件。 HSV-1 通过多种途径进入细胞，因此需要对每种途径的机制进行复杂的了解，以便于设计抗病毒药物以阻止病毒进入和传播。