Investigating the pathomechanisms underlying Charcot-Marie-Tooth Disease

项目总结 Charcot-Marie-Tooth(CMT)病是一种在遗传和临床上具有异质性的疾病。 以长运动和感觉受损为特征的遗传性周围神经病 轴突。这个项目的总体目标是确定分子和细胞过程 在不同的CMT基因之间共享，以帮助解决治疗该疾病的共同靶点 目前是不治之症。我们实验室广泛研究氨基酰-tRNA合成酶(AARs)， 参与CMT的最大基因家族，并发现了一个AARS的核功能， TyrRS被证明与CMT的发病有关，同时作为转录的 氧化应激下的调节器。目标1旨在了解核AAR如何在 氧化应激反应在小鼠生理中起作用，如果它是小鼠生理反应的共同点 CMT连锁的AARs。到目前为止的研究结果表明，小鼠的核TyrRs导致 听觉系统的新陈代谢和紊乱。这项提案旨在执行一项 纵向研究以确定听力损失是否为退行性的，以及在听力损失中的位置 通路有缺陷(如感觉上皮、螺旋神经节、脑干、中脑)，而 还使用组织样本上的RNA测序来检查负责的分子靶标。 此外，我们还发现CMT连接的AARs具有相似的核定位反应 仅在神经细胞中进行氧化应激治疗。目标1也着手调查这一点 明显的细胞类型特异性，检查更多的细胞系，并评估与 易位属性。更广泛地说，我想要了解多个 CMT基因和亚型对细胞器和信号有一个整体的看法 肌萎缩侧索硬化症的发病机制。因此，在目标2中，作为博士后实习生，我将 研究不同表型亚型的一系列CMT蛋白。患者派生，诱导 对于每个突变体，多能干细胞将被分化为两种相关的CMT细胞类型： 运动神经元和雪旺细胞。因为有证据表明线粒体缺陷 和某些CMT亚型的氧化应激，我将专门研究线粒体 使用成像和细胞分析的形态、动力学和功能，以及探索 氧化应激水平、应激相关损伤和潜在的通路在慢性应激中的影响 特定于细胞类型的方式。在这项提案期间，教学、写作研讨会、 掌握技术技能和参加会议将被强调，以使我具备 在神经科学领域从事独立职业所需的专业发展。

PROJECT SUMMARY Charcot-Marie-Tooth (CMT) disease is a genetically and clinically heterogeneous group of inherited peripheral neuropathies that is characterized by damage to long motor and sensory axons. The overall goal of this project is to identify the molecular and cellular processes that are shared between different CMT genes to help address a common target for treatment for this currently incurable disease. Our lab extensively studies aminoacyl-tRNA synthetases (aaRS), the largest gene family involved in CMT, and discovered the nuclear function of one aaRS, TyrRS, was shown to be associated to CMT pathogenesis while acting as a transcriptional regulator under oxidative stress. Aim 1 sets out to understand how the nuclear aaRS function in oxidative stress response plays a role in mouse physiology and if it is the commonality between CMT-linked aaRS. Findings so far suggest nuclear TyrRS in mice leads to an increased metabolism and disruption in the auditory system. This proposal sets out to perform a longitudinal study to determine if the hearing loss is degenerative and where in the auditory pathway there is a defect (e.g., sensory epithelium, spiral ganglion, brainstem, midbrain) while also examining the molecular targets responsible using RNA-Sequencing on tissue samples. Additionally, we uncovered that CMT-linked aaRS share a similar nuclear localization response upon oxidative stress treatment in neuronal cells only. Aim 1 also sets out to investigate this apparent cell type specificity, examine more cell lines, and evaluate the factor responsible for the translocation property. More broadly, I want to understand the connection between multiple CMT genes and subtypes to have a holistic view of the cellular organelles and signaling pathways underlying CMT pathomechanisms. Therefore, in Aim 2 as a postdoctoral trainee I will study a range of CMT proteins across subtypes of varying phenotypes. Patient derived, induced pluripotent stem cells will be differentiated into two relevant CMT cell types for each mutant: motor neurons and Schwann cells. Because there is evidence suggesting mitochondrial defects and oxidative stress in some CMT subtypes, I will specifically investigate mitochondrial morphology, dynamics, and function using imaging and cell-based assays, as well as, exploring the levels of oxidate stress, stress-related damage, and potential pathways affected in CMT in a cell type specific manner. During this proposal, activities such as teaching, writing workshops, mastery of technical skills, and conference participation will be emphasized to equip me with the professional development needed for an independent career in neuroscience.