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

• 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
• 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' 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

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：我作为独立研究人员职业的主要目标是了解不可或缺的一体 膜蛋白在内质网（ER）拥挤的环境中折叠。忠诚的破坏 过程导致许多人类疾病，包括阿尔茨海默氏症，帕金森氏症和charcot-marie-tooth病 （CMTD）。通过更好地理解这一过程，我希望最终确定治疗的新型治疗策略 患有这些疾病的患者。 CMTD是周围神经系统（PNS）和 折磨2500人中有1人。超过80％的患有这种疾病的患者在蛋白质编码中有突变 PMP22基因。 PMP22是一种四面体整合膜蛋白，在质膜（PM）上高度表达 PNS的骨髓雪旺细胞。 CMTD患者PMP22的基因剂量不当导致过多或 Schwann细胞PM的PMP22太少。据信，PM的PMP22的变化量会导致髓鞘 这些患者观察到异常。目前尚无CMTD的治疗方法。 PMP22在ER下方折叠 ER质量控制（QC）系统的监视。该系统都可以帮助PMP22折叠并介导 最终决定是将PMP22转向PM还是将蛋白质保留在急诊室中并最终靶向 它是为了退化。该提案的目标是了解调解该决策过程的因素。以前的 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 导致PM表达不同的系统。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的丰富膜域。已经显示了PNS的另一种膜蛋白P0的膜蛋白 ER中的胆固醇对于细胞表面运输是必需的。源自pmp22 - / - 小鼠显示的Schwann细胞显示 与WT Schwann细胞相比，迁移和广告能力降低和PM胆固醇含量降低。这 表明PMP22与富含胆固醇的结构域的关联对于Schwann细胞功能很重要。是我的 可以通过改变其蛋白质相互作用网络来调节PMP22细胞表面运输的假设 通过改变其与富含胆固醇的膜结构域相关的能力。为了解决这一假设，我 威尔：（1）在ER中发现PMP22相互作用的突变特异性变化，以调节其细胞表面运输 （2）检查导致PMP22与富含胆固醇的膜结构域关联的因素并评估影响 PMP22贩运的胆固醇协会。该建议的结果将发现新颖的蛋白质相互作用，并且 影响PMP22贩运和胆固醇协会的因素。这些信息将为科学家打开新颖的途径 试图为患有CMTD的患者开发治疗。