Structure, Folding, and Misfolding of PMP22

PMP22 的结构、折叠和错误折叠

• 批准号: 8039908
• 负责人: Bruce D Carter
• 金额: $ 30.53万
• 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 2013-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8039908
• 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; public health relevance; trafficking

DESCRIPTION (provided by applicant): 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. PUBLIC HEALTH RELEVANCE: Studies of the structure, folding, and stability of the human peripheral myelin protein 22 (PMP22) will be undertaken to unravel the molecular basis for Charcot-Marie Tooth Disease, a peripheral neuropathy. Results from this work are expected to contribute to novel therapeutic strategies for this human disease.

描述（由申请人提供）：编码外周髓蛋白蛋白22（PMP22）的基因中的遗传显性突变会导致其序列的单个氨基酸变化，导致髓鞘有缺陷，这是基本的人类外周神经病，Charcot-Marie-Marie-Marie-Marie-Marie-Marie-Marie-Marie-Marie-Marie-Marie-Marie-Marie-Marie-Marie-tool疾病型IA（CMTD）。据认为，CMTD突变在分泌途径早期导致PMP22的错误组装，从而导致蛋白质功能的丧失以及可能形成潜在的细胞毒性聚集体。该项目的总体目标是阐明与CMTD相关的突变对这种关键膜蛋白的结构，稳定性和折叠所产生的扰动的分子生物物理性质。我们还试图测试化学伴侣是否可以纠正通常观察到的PMP22 CMTD突变体形式的折叠缺陷。 AIM 1。使用NMR光谱法表征人PMP22的野生型（WT）和CMTD突变体的结构。 AIM 1将检验以下假设：PMP22的CMTD突变体形式在构象和/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生产和维持中的作用，并将提供有关氨基酸突变如何导致CMTD的生物物理见解。 PMP22结构的测定也将增加到当前人类膜蛋白结构的稀疏画廊。 AIM 2。表征PMP22的WT和CMTD突变体形式的稳定性和折叠动力学。 AIM 2将检验以下假设：PMP22与疾病相关的突变破坏蛋白质的稳定性。 AIM 2还将检验以下假设：与野生型蛋白质相比，与疾病相关的PMP22倍数更慢，/或效率低下。我们还将测试PMP22的CMTD突变体形式是否容易发生。目标3。确定化学伴侣是否可以增加PMP22的CMTD突变体形式的细胞表面表达。 AIM 3将检验以下假设：PMP22类似于其他与涉及蛋白质误配的疾病有关的人类膜蛋白，并且已经确定，使用化学伴侣可以恢复适当的折叠和运输。 公共卫生相关性：对人周围髓磷脂蛋白22（PMP22）的结构，折叠和稳定性的研究，以揭示周围神经病charcot-marie牙齿疾病的分子基础。这项工作的结果有望为这种人类疾病的新型治疗策略做出贡献。