Regulation of neuronal calcium transfer between mitochondria and lysosomes in health and neurodegeneration.

健康和神经变性中线粒体和溶酶体之间神经元钙转移的调节。

• 批准号: 10456299
• 负责人: Wesley J. Peng
• 金额: $ 5.18万
• 依托单位: NORTHWESTERN UNIVERSITY AT CHICAGO
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-09-30 至 2023-09-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10456299
• 关键词: Apoptosis; Automobile Driving; Biological Assay; Calcium; Cells; Data; Dementia; Development; Disease; Disease model; Electron Microscopy; Fostering; Functional disorder; Goals; Health; Homeostasis; Human; Image; Induced pluripotent stem cell derived neurons; Link; Lysosomes; Mediating; Membrane; Microscopy; Midbrain structure; Mitochondria; Modeling; Molecular; Mutation; Nerve Degeneration; Neurodegenerative Disorders; Neuroglia; Neurons; Optics; Organelles; PARK9 gene; Parkinsonian Disorders; Pathologic; Pathologic Processes; Pathway interactions; Patient-Focused Outcomes; Patients; Physicians; Physiological; Process; Production; Regulation; Research; Research Training; Resolution; Role; Scientist; Signal Transduction; Site; Syndrome; Techniques; aging brain; atypical parkinsonism; cell motility; cell type; differentiation protocol; dopaminergic neuron; human disease; improved; insight; live cell imaging; live cell microscopy; loss of function mutation; neurotransmitter release; new therapeutic target; novel; sensor

PROJECT SUMMARY Inter-organelle contact sites, which form dynamically between two different organelles and represent sites for metabolite transfer, have become increasingly appreciated as essential regulators of cellular homeostasis. Recently, our lab identified novel membrane contact sites between mitochondria and lysosomes in non-neuronal cells, which allow for bidirectional regulation of lysosomal and mitochondrial dynamics including mitochondrial fission and highlight a new pathway through which the two organelles can interact. Interestingly, both mitochondria and lysosomes are implicated in cellular calcium homeostasis, and dysfunction in both organelles has been linked to neurodegenerative disease. Calcium homeostasis is particularly important in neurons, where in addition to regulating functions such as ATP production and cellular signaling, calcium also modulates excitability and neurotransmitter release, suggesting that a more tightly-regulated mechanism of calcium transfer between organelles could be beneficial in neuronal cell types. Importantly, our preliminary data in non-neuronal cells suggest that activation of lysosomal calcium release increases mitochondrial calcium and that disruption of mitochondria-lysosome contact sites alters these calcium dynamics. Given these data, elucidating if and how mitochondria-lysosome contact sites transfer calcium in neurons will be critical for understanding how calcium dyshomeostasis may contribute to pathologic processes such as neurodegeneration. In this project, I propose to investigate the mechanisms and regulation of calcium dynamics at mitochondria-lysosome contact sites and their subsequent dysfunction in neurodegenerative disease using advanced microscopy techniques including super-resolution live cell microscopy and calcium imaging in long-term cultures of human induced pluripotent stem cell (iPSC)-derived neurons. In Aim 1, I will investigate the mechanisms of bidirectional calcium transfer at mitochondria-lysosome contact sites using human-derived cortical neurons. Additionally, as several lysosomal calcium transporters, including ATP13A2, have been implicated in neurodegenerative diseases, dysregulation of calcium dynamics between the two organelles may represent a potential pathway driving neurodegeneration. In Aim 2, I will investigate how disease-linked loss-of-function mutations in ATP13A2, which cause Kufor-Rakeb syndrome, an atypical form of parkinsonism with dementia, alter mitochondria-lysosome contact site dynamics and calcium homeostasis, and further contribute to downstream dysfunction in both organelles in patient-derived cortical and midbrain dopaminergic neurons. Together, the proposed research and training plan will offer important opportunities to not only acquire new experimental techniques in advanced imaging and human disease modeling to foster my development as a physician-scientist, but to also gain insight into the molecular mechanisms underlying neurodegeneration. A better understanding of these neuronal pathways will facilitate the identification of novel therapeutic targets, which may ultimately improve patient outcomes.

项目总结 细胞器间接触部位，在两个不同的细胞器之间动态形成并代表部位 对于代谢物的转移，已经越来越被认为是细胞内稳态的基本调节器。 最近，我们实验室在非神经细胞中发现了线粒体和溶酶体之间新的膜接触部位。 细胞，允许双向调节溶酶体和包括线粒体在内的线粒体动力学 并突出了两个细胞器可以相互作用的新途径。有趣的是，两者 线粒体和溶酶体与细胞内钙稳态和两个细胞器的功能障碍有关 与神经退行性疾病有关。钙稳态在神经元中尤其重要，在那里 除了调节ATP的产生和细胞信号转导等功能外，钙还可以调节 兴奋性和神经递质释放，表明钙转运机制受到更严格的调控 细胞器之间的相互作用对神经细胞类型可能是有益的。重要的是，我们的非神经性疾病的初步数据 细胞提示，溶酶体钙释放的激活增加了线粒体钙，并破坏了 线粒体-溶酶体接触部位改变了这些钙动力学。给出这些数据，阐明是否以及如何 线粒体-溶酶体接触部位在神经元中转运钙将是理解钙如何 动态平衡失调可能导致神经变性等病理过程。在这个项目中，我建议 探讨线粒体-溶酶体接触部位钙动力学的机制和调节 在神经退行性疾病中使用先进的显微镜技术，包括 长期培养的人诱导多能细胞的超分辨活细胞显微镜和钙成像 干细胞(IPSC)来源的神经元。在目标1中，我将研究双向钙转移的机制 使用人源性皮质神经元的线粒体-溶酶体接触部位。此外，由于几个溶酶体 包括ATP13A2在内的钙转运体与神经退行性疾病、调节失调有关 这两个细胞器之间的钙动力学变化可能代表了一条潜在的驱动神经退变的途径。 在目标2中，我将研究ATP13A2中与疾病相关的功能丧失突变是如何导致Kufor-Rakeb的 帕金森综合征是痴呆的一种非典型形式，它改变了线粒体-溶酶体接触部位的动力学 和钙稳态，并进一步促进患者来源的两个细胞器的下游功能障碍 皮质和中脑多巴胺能神经元。总之，拟议的研究和培训计划将提供 不仅获得先进成像和人类新实验技术的重要机会 疾病建模促进了我作为一名内科科学家的发展，同时也获得了对分子的洞察 神经退化的潜在机制。对这些神经元通路的更好理解将有助于 确定新的治疗靶点，这可能最终改善患者的结果。