Structure, Folding, and Misfolding of PMP22

PMP22 的结构、折叠和错误折叠

• 批准号: 8247008
• 负责人: Bruce D Carter
• 金额: $ 30.58万
• 依托单位: VANDERBILT UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-04-01 至 2014-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8247008
• 关键词: Afferent Neurons; Amino Acids; Biological; Cell Line; Cell surface; Cells; Charcot-Marie-Tooth Disease; Chemicals; Coculture Techniques; Defect; Disease; Genes; Goals; Human; Human Cell Line; Kinetics; Lead; Link; Maintenance; Membrane Proteins; Modeling; Molecular; Molecular Chaperones; Molecular Conformation; Mutation; Myelin; Myelin Proteins; NMR Spectroscopy; Nature; Pathway interactions; Peripheral; Peripheral Nervous System Diseases; Production; Proteins; Research; Role; Schwann Cells; Structure; Structure-Activity Relationship; Testing; Transgenic Mice; Work; base; cytotoxic; human PMP22 protein; human disease; insight; mouse model; mutant; novel therapeutics; overexpression; protein function; protein structure; trafficking

Project Summary Genetically dominant mutations in the gene that encodes peripheral myelin protein 22 (PMP22) lead to single amino acid changes in its sequence that result in defective myelin, underlying the common human peripheral neuropathy, Charcot-Marie-Tooth Disease Type IA (CMTD). It is believed that CMTD mutations result in misassembly of PMP22 early in the secretory pathway, resulting in the loss of protein function and also in the formation of potentially cytotoxic aggregates. The overall goal of this project is to elucidate the molecular biophysical nature of the perturbations made by CMTD-associated mutations to the structure, stability and folding of this critical membrane protein. We also seek to test whether chemical chaperones can correct the folding defects normally observed for CMTD mutant forms of PMP22. Aim 1. Characterize the structures of the wild type (WT) and CMTD mutant forms of human PMP22 using NMR spectroscopy. Aim 1 will test the hypothesis that CMTD mutant forms of PMP22 differ from the WT protein in terms of conformation and/or oligomeric state. Structural information will also illuminate PMP22's structure/function relationships and its role in myelin production and maintenance, and will provide biophysical insight into how amino acid mutations result in CMTD. Determination of PMP22's structure will also add to the currently sparse gallery of human membrane protein structures. Aim 2. Characterize the stability and folding kinetics of WT and CMTD mutant forms of PMP22. Aim 2 will test the hypothesis that disease-related mutations of PMP22 destabilize the protein. Aim 2 will also test the hypothesis that disease-related mutant forms of PMP22 fold more slowly and/or inefficiently than the wild type protein. We will also test whether CMTD mutant forms of PMP22 are aggregation-prone. Aim 3. Determine whether chemical chaperones can increase the cell surface expression of CMTD mutant forms of PMP22. Aim 3 will test the hypothesis that PMP22 is akin to other human membrane proteins that are linked to diseases involving protein misassembly and for which it has already been established that proper folding and trafficking can be restored using chemical chaperones.

项目概要 编码外周髓磷脂蛋白 22 (PMP22) 的基因发生显性遗传突变 导致其序列中的单个氨基酸发生变化，从而导致髓鞘质缺陷，这是 常见的人类周围神经病，IA 型腓骨肌萎缩症 (CMTD)。这是 认为 CMTD 突变导致 PMP22 在分泌途径早期错误组装， 导致蛋白质功能丧失，并形成潜在的细胞毒性物质 聚合体。该项目的总体目标是阐明分子生物物理性质 CMTD 相关突变对结构、稳定性和折叠造成的干扰 这种关键的膜蛋白。我们还试图测试化学伴侣是否可以纠正 通常在 PMP22 的 CMTD 突变体形式中观察到的折叠缺陷。 目标 1. 表征野生型 (WT) 和 CMTD 突变体形式的结构 使用核磁共振波谱法检测人 PMP22。目标 1 将检验 CMTD 突变体的假设 PMP22 的形式在构象和/或寡聚状态方面与 WT 蛋白不同。 结构信息还将阐明 PMP22 的结构/功能关系及其在 髓磷脂的产生和维持，并将提供有关氨基酸如何产生的生物物理学见解 突变导致 CMTD。 PMP22结构的确定也将补充到目前的 人类膜蛋白结构的稀疏画廊。 目标 2. 表征 WT 和 CMTD 突变体形式的稳定性和折叠动力学 PMP22。目标 2 将检验以下假设：PMP22 的疾病相关突变会破坏细胞的稳定性 蛋白质。目标 2 还将检验以下假设：与疾病相关的 PMP22 突变形式会折叠 比野生型蛋白质更慢和/或效率低。我们还将测试 CMTD 是否 PMP22 的突变形式具有聚集倾向。 目标 3. 确定化学伴侣是否可以增加细胞表面表达 PMP22 的 CMTD 突变体形式。目标 3 将检验 PMP22 与其他物质相似的假设 人膜​​蛋白与涉及蛋白质错误组装的疾病有关 已经确定可以使用以下方法恢复正确的折叠和运输 化学伴侣。