Function and Regulation of PMP22 in CMT1A and HNPP

PMP22 在 CMT1A 和 HNPP 中的功能和调控

基本信息

批准号：
10350403
负责人：
Kathryn Renae Moss
金额：
$ 12.3万
依托单位：
JOHNS HOPKINS UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2021
资助国家：
美国
起止时间：
2021-09-21 至 2026-08-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10350403
关键词：
Adherens Junction Adhesions Affect Aging Award Axon Biophysics Canis familiaris Career Transition Award Cell Adhesion Cell membrane Cell model Cells Charcot-Marie-Tooth Disease Complement Complex Confocal Microscopy Cultured Cells Development Disease Electrical Resistance Electron Microscopy Gene Dosage Genes Goals Hereditary neuropathy with liability to pressure palsies Human Inherited Intercellular Junctions Investigation Knowledge Label MDCK cell Membrane Membrane Microdomains Mentorship Microscopy Modeling Modification Molecular Neurobiology Morphology Myelin Nerve Nerve Fibers PMP22 gene Pathogenesis Peripheral Nerves Peripheral Nervous System Diseases Phase Phenotype Positioning Attribute Regulation Research Research Personnel Resolution Role Schwann Cells Tamoxifen Technical Expertise Techniques Therapeutic Tight Junctions Training Vesicle Work biophysical properties biophysical techniques career confocal imaging dosage dysmyelination improved kidney epithelial cell mouse model mutant myelination overexpression palmitoylation protein function recombinase-mediated cassette exchange success therapeutically effective therapy development

项目摘要

Project Summary/Abstract The fact that both duplication and deletion of the Peripheral Myelin Protein 22 (PMP22) gene cause dysmyelinating peripheral neuropathy illustrates the importance of PMP22 for peripheral myelin integrity. PMP22 duplication causes Charcot-Marie-Tooth Disease Type 1A (CMT1A) and PMP22 deletion causes Hereditary Neuropathy with Liability to Pressure Palsies (HNPP). Although CMT1A and HNPP are the most common inherited peripheral neuropathies, research on them is underfunded and there are currently no disease-modifying treatments. This is largely due to the fact that PMP22 function and the consequence of altered PMP22 expression remain unclear. Thus, there is a critical need to expand knowledge of what PMP22 does in myelin, how it is regulated and when precise expression is required as a means to improve therapeutic potential of CMT1A and HNPP. This proposal aims to utilize cutting-edge techniques, including conditional mouse models and super resolution microscopy, and knowledge of cell adhesion and membrane biophysics to advance understanding of CMT1A and HNPP pathomechanisms. My central hypothesis is that PMP22 gene dosage and lipid raft association govern localization and organization of myelin adherens and tight junctions; a function that is most critical during development. In Aim 1, I will determine how PMP22 regulates adhesion junction organization in peripheral nerve myelin during development and aging with super resolution and electron microscopy. I will aid the interpretation of these studies by evaluating the effects of altered PMP22 expression on prototypical adherens and tight junctions in Madin-Darby Canine Kidney (MDCK) epithelial cells. The temporal requirement for precise PMP22 expression in myelin will also be defined by generating powerful conditional mouse models of CMT1A and HNPP. In Aim 2, I will determine how palmitoylation impacts PMP22 lipid raft association and regulation of adhesion junctions and define the biophysical properties of PMP22 within the plasma membrane using MDCK and Schwann cell models of CMT1A and HNPP and advanced biophysical methods. This K22 Career Transition Award will provide me with additional training, mentorship and expertise in cell adhesion, membrane biophysics and microscopy, thereby enabling my proposed research and facilitating my transition to independence. This training will complement my previous training in cell and molecular neurobiology and my current peripheral nerve training, and the expertise acquired during Phase I will be applied to more complex models in Phase II to expand mechanistic details. Completion of these aims will accelerate progress towards my long-term goal of developing an independent academic research career studying pathomechanisms of CMT1A and HNPP as a means to improve their therapeutic potential. The training and mentorship provided by this award will expand my technical skills and expertise, positioning me for success as an independent investigator.

项目概要/摘要外周髓磷脂蛋白 22 (PMP22) 基因的重复和缺失都会导致髓鞘形成障碍周围神经病说明了 PMP22 对于外周髓磷脂完整性的重要性。 PMP22 重复导致 1A 型腓骨肌萎缩症 (CMT1A) 和 PMP22 缺失导致伴有压力性麻痹的遗传性神经病（HNPP）。虽然 CMT1A 和 HNPP 是最常见的遗传性周围神经病，对其研究资金不足，目前尚无疾病缓解治疗。这主要是由于 PMP22 的功能和结果 PMP22 表达的改变仍不清楚。因此，迫切需要扩展 PMP22 的知识髓磷脂中的作用、其调节方式以及何时需要精确表达作为改善治疗的手段 CMT1A 和 HNPP 的潜力。该提案旨在利用尖端技术，包括条件小鼠模型和超分辨率显微镜，以及细胞粘附和膜生物物理学知识加深对 CMT1A 和 HNPP 病理机制的了解。我的中心假设是 PMP22 基因剂量和脂筏关联控制髓磷脂粘附和紧密的定位和组织路口；开发过程中最关键的功能。在目标 1 中，我将确定 PMP22 如何在发育和衰老过程中调节周围神经髓磷脂的粘附连接组织分辨率和电子显微镜。我将通过评估这些研究的影响来帮助解释这些研究 Madin-Darby 犬肾 (MDCK) 中原型粘附体和紧密连接上 PMP22 表达的改变上皮细胞。髓磷脂中 PMP22 精确表达的时间要求也将由下式定义：生成强大的 CMT1A 和 HNPP 条件小鼠模型。在目标 2 中，我将确定如何棕榈酰化影响 PMP22 脂筏关联和粘附连接的调节，并定义使用 MDCK 和 Schwann 细胞模型研究质膜内 PMP22 的生物物理特性 CMT1A 和 HNPP 以及先进的生物物理方法。这个 K22 职业转型奖将为我提供细胞粘附、膜生物物理学和显微镜学方面的额外培训、指导和专业知识，从而实现我提出的研究并促进我向独立的过渡。此次培训将补充我之前接受的细胞和分子神经生物学培训以及我目前的周围神经培训，以及在第一阶段获得的专业知识将应用于第二阶段更复杂的模型，以扩展机制细节。完成这些目标将加速实现我的长期目标：研究 CMT1A 和 HNPP 病理机制的独立学术研究生涯提高他们的治疗潜力。该奖项提供的培训和指导将扩展我的能力技术技能和专业知识使我能够成为一名成功的独立调查员。