MEASLES VIRUS AND ITS CELLULAR RECEPTOR CD46

麻疹病毒及其细胞受体CD46

• 批准号: 6534165
• 负责人: THILO STEHLE
• 金额: $ 21.01万
• 依托单位: MASSACHUSETTS GENERAL HOSPITAL
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-09-30 至 2004-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6534165
• 关键词: CD antigens; X ray crystallography; antiviral antibody; epitope mapping; measles virus; microorganism hemagglutinin; polymerase chain reaction; protein structure function; receptor binding; receptor expression; site directed mutagenesis; tissue /cell culture; virus antigen; virus receptors

The goal of this proposal is to understand the interactions between measles virus and its cellular receptor in order to provide a basis for the design of anti-viral drugs. Despite an available vaccine, measles remains one of the major causes of child death worldwide, and our work will guide efforts to find new ways to control this pathogen. We will determine the three- dimensional structures of measles virus hemagglutinin and of human CD46, a measles virus receptor. The physiological role for CD46 is as a cofactor that accelerates the deactivation of the third and fourth complement components, thereby protecting host cells from complement-dependent attack. It appears that measles virus and the physiological ligands for CD46 bind to discrete parts of the molecule. Specifically, the extracellular portion of CD46 consists of four short consensus repeats (SCRs) that contain binding sites for the measles virus hemagglutinin (in SCR1-SCR2) and complement regulatory activity (in SCR2-SCR4). One can therefore envisage the discovery of selective anti-viral inhibitors. The experiments described in Specific Aim 1 concern the expression, crystallization and X-ray structure determination of several two-domain CD46 fragments as well as a fragment that comprises all four SCRs. Since the molecule probably has some interdomain flexibility, studying the two-domain fragments increases the likelihood of obtaining crystals that can diffract to molecular resolution. Crystals for the SCR1-SCR2 fragment have already been produced, and the structure determination of this fragment has been achieved. In Specific Aim 2, we will use this structural information as a guide to carry out site-directed mutagenesis experiments and measles virus binding studies that will probe the interactions with the virus in more detail. In parallel, we will express and crystallize a soluble form of the measles virus hemagglutinin protein that contains the CD46 binding site, and we will determine its crystal structure as part of Aim 2. These structural studies are a necessary antecedent for rational drug design against measles virus. They are also likely to provide insights into strategies for vaccine and drug design against paramyxoviruses such as respiratory syncytial virus in general.

本研究的目的是了解麻疹病毒与其细胞受体之间的相互作用，为抗病毒药物的设计提供依据。 尽管有可用的疫苗，麻疹仍然是全球儿童死亡的主要原因之一，我们的工作将指导寻找控制这种病原体的新方法的努力。 我们将确定麻疹病毒血凝素和人CD 46（麻疹病毒受体）的三维结构。 CD 46的生理作用是作为辅助因子，加速第三和第四补体成分的失活，从而保护宿主细胞免受补体依赖性攻击。 麻疹病毒和CD 46的生理配体似乎与分子的离散部分结合。 具体而言，CD 46的细胞外部分由四个短的共有重复序列（SCR）组成，其含有麻疹病毒血凝素（在SCR 1-SCR 2中）和补体调节活性（在SCR 2-SCR 4中）的结合位点。因此，人们可以设想发现选择性抗病毒抑制剂。 具体目标1中描述的实验涉及几种双结构域CD 46片段以及包含所有四种SCR的片段的表达、结晶和X射线结构测定。 由于该分子可能具有一定的域间柔性，因此研究双域片段增加了获得能够达到分子分辨率的晶体的可能性。 SCR 1-SCR 2片段的晶体已经产生，并且已经实现了该片段的结构测定。 在具体目标2中，我们将使用这种结构信息作为指导，进行定点诱变实验和麻疹病毒结合研究，这些研究将更详细地探测与病毒的相互作用。 与此同时，我们将表达和结晶含有CD 46结合位点的麻疹病毒血凝素蛋白的可溶性形式，我们将确定其晶体结构作为目标2的一部分。 这些结构研究是合理设计抗麻疹病毒药物的必要前提。 它们也可能为针对副粘病毒（如呼吸道合胞病毒）的疫苗和药物设计策略提供见解。