Uncovering Protein Interactions and Membrane Phase Preferences that alter the Plasma Membrane trafficking of Peripheral Myelin Protein 22

揭示改变外周髓鞘蛋白质膜运输的蛋白质相互作用和膜相偏好 22

基本信息

批准号：
10011580
负责人：
Justin Tyler Marinko
金额：
$ 1.59万
依托单位：
VANDERBILT UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2019
资助国家：
美国
起止时间：
2019-07-01 至 2020-12-12
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10011580
关键词：
Actins Address Adhesions Affect Alzheimer&apos s Disease Binding Biological Biological Assay Cell membrane Cell physiology Cell surface Cells Charcot-Marie-Tooth Disease Cholesterol Collaborations Confocal Microscopy Crowding Cytoskeleton DNA Sequence Alteration Data Disease Endoplasmic Reticulum Environment Flow Cytometry Gene Deletion Gene Dosage Gene Duplication Genes Goals Hela Cells Hereditary neuropathy with liability to pressure palsies Hydrophobicity Impairment Individual Integral Membrane Protein Lead Link Mass Spectrum Analysis Mediating Membrane Membrane Proteins Microscopy Missense Mutation Molecular Molecular Conformation Monitor Mus Mutate Mutation Mutation Analysis Myelin Neurodegenerative Disorders Neuropathy PMP22 gene Parkinson Disease Patients Peripheral Nervous System Peripheral Nervous System Diseases Phase Play Post-Translational Protein Processing Process Protein Glycosylation Proteins Proteomics Quality Control Rattus Research Research Personnel Role Schwann Cells Scientist Small Interfering RNA Syndrome System Testing Therapeutic Transfection Vesicle Work base career human disease knock-down member migration mutant novel novel therapeutics overexpression palmitoylation preference protein expression protein folding screening small molecule small molecule libraries symptom management trafficking

项目摘要

PROJECT SUMMARY: A major goal of my career as an independent researcher is to understand how integral membrane proteins fold in the crowded environment of the endoplasmic reticulum (ER). Disruptions in the fidelity of this process lead to a number of human diseases including Alzheimer’s, Parkinson’s and Charcot-Marie-Tooth Disease (CMTD). By better understanding this process, I hope to eventually identify novel therapeutic strategies for treating patients afflicted with these diseases. CMTD is the most common neuropathy of the peripheral nervous system (PNS) and afflicts 1 in 2,500 individuals. Over 80% of patients afflicted with this disease have a mutation in the protein encoding PMP22 gene. PMP22 is a tetraspan integral membrane protein that is highly expressed at the plasma membrane (PM) of myelinating Schwann cells of the PNS. Improper gene dosage of PMP22 in CMTD patients results in either too much or too little PMP22 at the PM of Schwann cells. The altered amount of PMP22 at the PM is believed to cause the myelin abnormalities observed in these patients. There are currently no treatments for CMTD. PMP22 folds in the ER under the surveillance of the ER quality control (QC) system. This system both helps PMP22 to fold as well as mediates the ultimate decision whether to traffic PMP22 forward towards the PM or to retain the protein in the ER and ultimately target it for degradation. The goals of this proposal are to understand the factors that mediate this decision process. Previous results show that wild type (WT) PMP22 and PMP22 disease mutants have different protein interactions in the ER QC system leading to varying PM expression. Preliminary data shows that selective modulation of protein expression in ER can alter the cell surface trafficking of PMP22 and its disease mutants. Additionally, PMP22 associates with cholesterol rich membrane domains at the PM. It has been shown for another membrane protein of the PNS, P0, that association with cholesterol in the ER is necessary for cell surface trafficking. Schwann cells derived from PMP22 -/- mice show decreased migration and adhesion capabilities and lower PM cholesterol content compared to WT Schwann cells. This indicates that PMP22 association with cholesterol rich domains is important for Schwann cell function. It is my hypothesis that PMP22 cell surface trafficking can be modulated by both changing its protein interaction network in the ER and through altering its ability to associate with cholesterol rich membrane domains. To address this hypothesis, I will: (1) uncover mutation specific changes to the PMP22 interactome in the ER that modulate its cell surface trafficking and (2) examine the factors that cause PMP22 to associate with cholesterol rich membrane domains and assess the effects of cholesterol association on PMP22 trafficking. The results from this proposal will uncover novel protein interactions and factors that affect PMP22 trafficking and cholesterol association. This information will open novel avenues for scientists attempting to develop therapeutics for patients who suffer from CMTD.

项目摘要：作为一名独立研究人员，我职业生涯的一个主要目标是了解如何整合膜蛋白在内质网 (ER) 的拥挤环境中折叠，其保真度受到破坏。这一过程会导致许多人类疾病，包括阿尔茨海默病、帕金森病和腓骨肌萎缩症（CMTD）通过更好地理解这个过程，我希望最终找到新的治疗策略。患有这些疾病的患者是最常见的周围神经系统 (PNS) 和神经病。每 2,500 人中就有 1 人患有这种疾病，超过 80% 的患者的蛋白质编码存在突变。 PMP22 基因 PMP22 是一种四跨整合膜蛋白，在质膜 (PM) 上高度表达。 CMTD 患者的 PMP22 基因剂量不当会导致 PNS 的髓鞘化雪旺细胞过多或过少。雪旺细胞 PM 处的 PMP22 含量太少据信 PM 处 PMP22 含量的改变会导致髓鞘质的形成。目前尚无针对 ER 中 PMP22 折叠的治疗方法。 ER 质量控制 (QC) 系统的监视该系统既帮助 PMP22 折叠又调节 PMP22 的折叠。最终决定是将 PMP22 向前输送至 PM 还是将蛋白质保留在 ER 中并最终靶向该提案的目标是了解影响这一决策过程的因素。结果表明，野生型（WT）PMP22 和 PMP22 疾病突变体在 ER QC 中具有不同的蛋白质相互作用初步数据表明，ER 中蛋白质表达的选择性调节。可以改变 PMP22 及其疾病突变体的细胞表面运输，此外，PMP22 与胆固醇相关。 PM 上丰富的膜结构域已被证明与 PNS 的另一种膜蛋白 P0 相关。内质网中的胆固醇对于源自 PMP22 -/- 小鼠的雪旺细胞表面运输是必需的。与 WT 雪旺细胞相比，迁移和粘附能力降低，PM 胆固醇含量降低。表明 PMP22 与富含胆固醇的结构域的关联对于雪旺细胞功能很重要。假设 PMP22 细胞表面运输可以通过改变其蛋白质相互作用网络来调节 ER 并通过改变其与富含胆固醇的膜域相关的能力来解决这一假设。将：(1) 揭示 ER 中 PMP22 相互作用组的突变特异性变化，调节其细胞表面运输 (2) 检查导致 PMP22 与富含胆固醇的膜域结合的因素并评估其影响该提案的结果将揭示新的蛋白质相互作用和影响 PMP22 运输和胆固醇关联的因素这一信息将为科学家开辟新的途径。尝试为患有 CMTD 的患者开发治疗方法。