NMR STRUCTURAL STUDIES OF PRION PROTEINS WITH POINT MUTATIONS

点突变朊病毒蛋白的核磁共振结构研究

• 批准号: 7447340
• 负责人: PETER Edwin WRIGHT
• 金额: $ 38.91万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
• 依托单位国家: 美国
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-06-15 至 2008-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7447340
• 关键词: Address; Behavior; Binding; Binding Sites; Chemicals; Disease; Disease susceptibility; Dominant-Negative Mutation; Exhibits; Genes; Gerstmann-Straussler-Scheinker Disease; Imagery; Inherited; Knowledge; Laboratories; Lead; Maps; Measures; Methods; Mus; Mutant Strains Mice; Mutation; Nature; Numbers; Patients; Pharmaceutical Preparations; Phenotype; Point Mutation; Predisposition; Preparation; Prion Diseases; Prions; Property; Proteins; Quinacrine; Resolution; Sampling; Scrapie; Site; Solutions; Structure; System; Techniques; Testing; Therapeutic; analog; base; design; insight; iterative design; mutant; novel; polypeptide; programs; research study; small molecule; three dimensional structure

Although a large amount of structural information is available on the cellular prion protein from a number of species, little beyond the bare knowledge of secondary structure content available from CD spectra is available for the disease-causing scrapie form of the protein. Given the multimeric and insoluble nature of this form of the protein, it appears unlikely that high-resolution structural information will be forthcoming on this form of the protein in the absence of breakthroughs in sample preparation or spectroscopic techniques. One approach to this problem is to examine the underlying structural basis for the enhanced disease susceptibility of mutant forms of the protein found in familial prion diseases, together with the reduced susceptibility found for certain dominant negative prion protein mutants. In order to address this question, this project will investigate the structure and dynamics of three mutant forms of the minimal infective domain (PrP90-231) of the mouse prion protein. In Specific Aim 1, the high-resolution NMR solution structures will be calculated and polypeptide chain dynamics will be analyzed for two mutant proteins that exhibit dominant negative phenotypes (that is, exhibit a lower propensity for prion disease than wild-type). These studies will have direct relevance and utility for the Program, providing detailed structural information that can be used for structure-based design of therapeutics. A control system, the P102L mutant protein frequently found in the inherited Gerstmann-Straussler-Scheinker disease, will be studied in Specific Aim 2. A high-resolution solution structure will be calculated for this protein, which shows increased propensity for prion formation. Polypeptide chain dynamics measured by NMR will also be an important component of this part of the project. Specific Aim 3 involves the direct visualization of the sites of binding of the therapeutic drugs developed in this Program using the technique of NMR chemical shift mapping. The studies in Specific Aims 1-3 should prove to be of direct use to other components of the Program Project, by providing information vital to the iterative design of novel, effective therapeutics. In addition, it is anticipated that important insights will be gained into the structural basis of the conversion of prion proteins to insoluble disease-causing forms.

尽管可以从许多物种的细胞prion蛋白上获得大量的结构信息，但除了对CD光谱可用的二级结构含量的裸露知识可用于该蛋白质的引起疾病的crapie形式。鉴于这种蛋白质形式的多种和不溶性的性质，如果在样品制备或光谱技术中没有突破性的情况下，这种蛋白质的高分辨率结构信息似乎不可能出现在这种形式的蛋白质上。解决此问题的一种方法是检查家族型prion疾病中发现的蛋白质突变形式增强的疾病敏感性，以及对于某些主要的负prion蛋白突变体发现的易感性降低。为了解决这个问题，该项目将研究最小的三种突变形式的结构和动力学 小鼠prion蛋白的感染结构域（PRP90-231）。在特定的目标1中，将计算高分辨率NMR溶液结构，并将分析两种表现出显性阴性表型的突变蛋白的多肽链动力学（也就是说，比野生型的prion病倾向较低）。这些研究将对该计划具有直接的相关性和实用性，提供可用于基于结构的治疗设计的详细结构信息。将在特定的目标2中研究了一个控制系统，即在遗传的Gerstmann-Straussler-Scheinker病中经常发现的P102L突变蛋白。将计算出该蛋白的高分辨率溶液结构，这表明对prion形成的倾向增加。 NMR测量的多肽链动力学也将是该项目的重要组成部分。特定目标3涉及直接 使用NMR化学移位映射技术在该程序中开发的治疗药物结合位点的可视化。特定目标1-3中的研究应被证明是直接用于程序项目的其他组件，通过提供对新颖，有效疗法的迭代设计至关重要的信息。此外，预计重要的见解将获得prion蛋白转化为不溶性造成病的形式的结构基础。