FUNCTIONAL ANALYSIS OF RSV ENVELOPE GLYCOPROTEIN

RSV 包膜糖蛋白的功能分析

• 批准号: 6376573
• 负责人: Paul Bates
• 金额: $ 26.24万
• 依托单位: UNIVERSITY OF PENNSYLVANIA
• 依托单位国家: 美国
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-07-01 至 2003-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6376573
• 关键词: Retroviridae; Rous sarcoma virus; conformation; enzyme linked immunosorbent assay; gene mutation; glycoproteins; laboratory mouse; laboratory rabbit; membrane fusion; molecular cloning; monoclonal antibody; protein structure function; receptor binding; virus envelope; virus infection mechanism; virus protein; virus receptors; western blottings

Enveloped viruses utilize glycoproteins on their surface to mediate entry into the target host cell. Conserved features in many viral glycoproteins suggest that they function in a similar manner to accomplish the common goal of viral entry into the host. Entry involves both recognition of specific receptors on the host surface and fusion of the viral and host cell membranes. The viral glycoproteins mediate both of these events. For many viruses, viral entry takes place after endocytosis where the acidic environment of the endosome triggers conformational changes in the viral glycoprotein(s) that result in membrane fusion. Fusion appears to require the concerted action of several oligomeric glycoproteins, thus the conformational changes are likely to also be synchronous and this synchrony is easily obtained with a trigger such as a low pH environment. Retroviruses, including Rous sarcoma virus (RSV), and a number of other virus families enter cells in a pH-independent manner. Thus, the cue for the proposed glycoprotein conformational changes for these pH-independent viruses is unclear. Indeed, the relevant conformational changes that lead to fusion are ill- defined for viruses utilizing a neutral pH entry pathway. Although the glycoproteins of many pH-dependent and independent viruses are similar, the study of neutral pH entry has been slowed by our lack of knowledge about, or ability to trigger, a fusogenic conformation for the viral glycoproteins. The overall goal of this project is to analyze viral entry in a model retroviral system. Because of the availability of a cloned host receptor (Tva) that is easily manipulated and a well characterized viral envelope protein, RSV represents an ideal system to study pH-independent retroviral entry. This analysis will focus on the molecular details of the interaction of the viral envelope protein and the receptor, the effects of this interaction on the Env protein, the regions in Env that mediate these effects, and finally the relationship of changes that occur in Env to membrane fusion. The specific aims to be pursued are: 1) Produce mutations in defined regions of env and study their effects separately on a) receptor binding, b) receptor-induced conformational changes of envelope, c) membrane fusion, and d) infection. 2) Employ a genetic selection strategy to isolate viruses with alterations in envelope that allow escape from soluble receptor or that suppress of an envelope or receptor defect. 3) Determine the consequences of the Tva/EnvA interaction: cooperative effects on conformational changes, characterization of activated EnvA, and analysis of the effects of peptides to conserved regions of TM.

包裹的病毒利用表面上的糖蛋白进行介导 进入目标主机单元。 许多病毒的保守特征 糖蛋白表明它们以类似的方式起作用 实现病毒进入宿主的共同目标。 进入涉及 两者都识别宿主表面上特定受体和融合 病毒和宿主细胞膜的。病毒糖蛋白介导 这两个事件。 对于许多病毒，病毒进入之后发生 内吞作用，内体触发的酸性环境 导致病毒糖蛋白的构象变化 膜融合。 融合似乎需要一致的行动 几种低聚糖蛋白，因此构象变化是 也可能是同步的，并且可以轻松获得此同步 诸如低pH环境之类的触发因素。逆转录病毒，包括弹药 肉瘤病毒（RSV），其他许多病毒家族进入细胞 以pH无关的方式。因此，提出的糖蛋白的提示 这些独立于pH的病毒的构象变化尚不清楚。 确实，导致融合的相关构象变化是不良的 用于使用中性pH进入途径的病毒定义。虽然 许多pH依赖性和独立病毒的糖蛋白相似， 我们缺乏知识的中性pH输入的研究减慢了 关于触发或触发能力，病毒的融合构象 糖蛋白。 该项目的总体目标是分析病毒 进入模型逆转录病毒系统。 由于可用 克隆的宿主受体（TVA）容易被操纵且井 表征病毒包膜蛋白，RSV代表了一个理想的系统 研究pH非依赖性逆转录病毒进入。 该分析将重点放在 病毒包膜蛋白与 受体，这种相互作用对env蛋白的影响， ENV中调解这些影响的地区，最后是关系 膜融合中发生的变化。 具体目的 被追捕是：1）在确定的环境区域中产生突变 它们分别对A）受体结合的影响，B）受体诱导 信封的构象变化，c）膜融合和D） 感染。 2）采用遗传选择策略来分离病毒 随着信封的改变，可以逃离可溶的受体或 抑制信封或受体缺陷。 3）确定 TVA/Enva互动的后果：合作对 构象变化，激活Enva的表征和分析 肽对TM保守区域的影响。