Investigating the Role of LRRK2 Hyperactivity in Autophagic and Synaptic Deficits

研究 LRRK2 过度活跃在自噬和突触缺陷中的作用

• 批准号: 10549286
• 负责人: Dan Dou
• 金额: $ 3.5万
• 依托单位: UNIVERSITY OF PENNSYLVANIA
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10549286
• 关键词: Affect; Age; Aging; Autophagocytosis; Axon; Biogenesis; Clinical; Complement; Complex; Data; Dementia; Dependence; Development; Disease; Disease model; Environment; Foundations; Functional disorder; Future; Genetic; Goals; Homeostasis; Human; Hyperactivity; Idiopathic Parkinson Disease; Image; Impaired cognition; Impairment; Induced pluripotent stem cell derived neurons; LRRK2 gene; Label; Link; Lysosomes; Mentors; Mitochondria; Motor; Mutation; Nerve Degeneration; Neurodegenerative Disorders; Neurons; Organelles; PHluorin; Parkinson Disease; Pathogenesis; Pathogenicity; Pathologic; Pathway interactions; Patients; Peptide Hydrolases; Phospho-Specific Antibodies; Phosphorylation; Phosphotransferases; Physicians; Physiological; Play; Population; Prevalence; Process; Proteins; Regulation; Repression; Research; Rodent; Role; Scientist; Severities; Synapses; Synaptic Transmission; Synaptic Vesicles; Synaptophysin; Testing; Therapeutic; Training; Transmembrane Transport; Travel; Vesicle; Work; Writing; age related; burden of illness; causal variant; cognitive impairment in Parkinson' s; dominant genetic mutation; experimental study; fluorescence imaging; healthy aging; human disease; improved; in vivo; induced pluripotent stem cell; inhibitor; neuronal cell body; non-motor symptom; presynaptic; rab GTP-Binding Proteins; recruit; retrograde transport; therapeutically effective; vesicle transport; vesicular release

PROJECT SUMMARY Parkinson’s disease (PD) is the second-most prevalent neurodegenerative disease and the fastest- growing. PD increases in both prevalence and severity with age, and the disease burden is projected to dramatically increase in coming decades as the population ages. Current therapies do not address the underlying neurodegeneration, and development of improved therapeutics is hindered by poor understanding of the pathogenesis. Changes in homeostatic regulation of both autophagy and synaptic transmission have been implicated in not only PD but also physiological aging. Leucine-rich repeat kinase 2 (LRRK2) is a leading candidate for a nexus bridging autophagy and PD pathogenesis. Mutations in LRRK2 are the most common genetic cause of PD, and increased LRRK2 kinase activity has also been linked to idiopathic PD. There is accumulating evidence that multiple PD-causative pathways may converge on disrupting autophagy through mechanisms dependent on LRRK2 activity. Recently, LRRK2 was shown to phosphorylate a subset of Rab GTPases, providing an important opportunity to make advances in the understanding of mechanisms downstream of LRRK2. The goal of this proposal is to elucidate the role that LRRK2 may play in autophagy and synaptic homeostasis, in the context of pathogenic mutations associated with PD. Our preliminary data suggests that the most common pathogenic mutation in LRRK2, p.G2019S, disrupts autophagic vesicle (AV) transport in the axons of rodent and iPSC-derived human neurons. We hypothesize that multiple pathogenic PD mutations disrupt autophagy and synaptic vesicle precursor (SVP) transport through mechanisms dependent on increased LRRK2 kinase activity. To test this hypothesis, we will exploit iPSC-derived neurons as a human disease model. Experiments proposed in Aim 1a will explore whether LRRK2-p.G2019S causes deficits in AV cargo degradation, as a potential mechanism of neurodegeneration. In Aim 1b, we will determine whether the VPS35-p.D620N mutation, a different pathogenic PD mutation that increases LRRK2 activity, causes similar autophagy deficits as LRRK2-p.G2019S. Finally, in Aim 2, we will explore whether SVP transport from the soma to the axon is impaired by mutations causing LRRK2 hyperactivity, with potential ramifications for synaptic homeostasis. Collectively, we expect that these Aims will help elucidate mechanisms by which multiple causes of PD can converge on a LRRK2-dependent pathway to disrupt neuronal autophagy and synaptic homeostasis. Additionally, this work may provide a foundation for future work to shed light on pathways by which physiological aging alters these processes in the absence of diseases of aging. To complement this research plan, a comprehensive training plan will help the trainee meet specific Research Goals, Professional Goals (including writing, mentoring, and presentation), and Clinical Goals (tying together an integrated physician-scientist training pathway), all in a supportive, collaborative scientific environment.

项目摘要 帕金森氏病（PD）是最流行的神经退行性疾病，是最快的 生长。 PD的患病率和严重程度随着年龄的增长而增加，伯恩疾病预计 随着人口年龄的增长，在未来几十年中动态增加。当前疗法没有解决 不良的理解阻碍了潜在的神经变性和改善治疗的发展 发病机理。自噬和突触传播的体内平衡调节的变化具有 不仅与PD有关，还与身体衰老有关。富含亮氨酸的重复激酶2（LRRK2）是领先 Nexus桥接自噬和PD发病机理的候选者。 LRRK2中的突变是最常见的 PD的遗传原因和LRRK2激酶活性增加也与特发性PD有关。有 累积证据表明多种PD促途径可能会在破坏自噬通过 机制取决于LRRK2活性。最近，显示LRRK2可以磷酸化Rab的子集 GTPases，提供了一个重要的机会，可以进步对机制的理解 LRRK2的下游。该提案的目的是阐明LRRK2在自噬中扮演的角色 和突触稳态，在与PD相关的致病突变的背景下。我们的初步数据 表明LRRK2，P.G2019S中最常见的致病突变破坏了自噬囊泡（AV） 在啮齿动物和IPSC衍生的人类神经元的轴突中运输。我们假设多种致病性 PD突变破坏自噬和突触囊泡前体（SVP）通过机制运输 取决于LRRK2激酶活性的增加。为了检验该假设，我们将利用IPSC衍生的神经元 作为人类疾病模型。 AIM 1A中提出的实验将探讨LRRK2-P.G2019S是否原因 AV货物降解的缺陷，是神经退行性的潜在机制。在AIM 1B中，我们将确定 VPS35-P.D620N突变是否会增加LRRK2活性的不同致病性PD突变， 引起与LRRK2-P.G2019S相似的自噬防御能力。最后，在AIM 2中，我们将探讨是否高级副总裁 从SOMA到轴突的运输受到引起LRRK2多动症的突变的损害，潜力 突触稳态的后果。总的来说，我们希望这些目标将有助于阐明机制 通过这种原因，PD的多种原因可以在LRRK2依赖性途径上收敛以破坏神经元自噬 和突触稳态。此外，这项工作可能为将来的工作提供基础，以阐明 在没有衰老疾病的情况下，身体衰老会改变这些过程的途径。到 补充该研究计划，一项全面的培训计划将有助于学员满足特定的研究 目标，职业目标（包括写作，心理和演示）以及临床目标（将 在支持性的协作科学环境中，是一种综合的物理科学训练途径）。