14-3-3 phosphorylation in Parkinson's disease

帕金森病中的 14-3-3 磷酸化

• 批准号: 10660102
• 负责人: Talene Alene Yacoubian
• 金额: $ 7.19万
• 依托单位: UNIVERSITY OF ALABAMA AT BIRMINGHAM
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-09-15 至 2025-05-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10660102
• 关键词: Affect; Binding; Biological Assay; Brain; Cell Communication; Cells; Clinical; Data; Dementia with Lewy Bodies; Detergents; Disease; Disease Progression; Disinhibition; Event; Functional disorder; Genes; Goals; Human; Idiopathic Parkinson Disease; Immunoprecipitation; Impaired cognition; Impairment; Intervention; Knock-in; Knock-in Mouse; LRRK2 gene; Lead; Lewy Body Disease; Ligation; Link; Measures; Mediating; Mitochondria; Modeling; Molecular Chaperones; Mus; Mutation; Nerve Degeneration; Neurodegenerative Disorders; Neuronal Injury; Neurotoxins; Outcome; Oxidative Stress; Oxidative Stress Induction; Parkinson Disease; Pathogenesis; Pathologic; Pathology; Patients; Pesticides; Phosphorylation; Phosphotransferases; Process; Protein Isoforms; Proteins; Publishing; Research; Risk; Risk Factors; Role; Rotenone; Severities; Stress; Surface Plasmon Resonance; Testing; Toxic effect; Toxin; Variant; alpha synuclein; autosome; brain tissue; genome wide association study; in vivo; link protein; mimetics; mouse model; mutant; neurotoxicity; novel; paracrine; pre-clinical; prevent; protective effect; protein transport; response; sporadic Parkinson' s Disease; therapeutic target; tool; transmission process

PROJECT SUMMARY Two critical proteins linked to Parkinson’s disease (PD) are alpha-synuclein (αsyn) and LRRK2. Mutations in either gene cause autosomal dominant forms of PD, and GWAS studies have pointed to variants in both genes as risk factors for developing idiopathic PD. Although both proteins lead to a similar pathological outcome, how these two proteins cause neuronal injury and how they interact in the disease process are not well understood. Our key discovery is that 14-3-3θ is a major regulator of both αsyn and LRRK2 and could be the missing link between αsyn and LRRK2. 14-3-3s are multifunctional, highly expressed brain proteins that act as chaperones, affect protein trafficking, and modulate enzymatic activity of their binding partners. Our research has highlighted the role of these critical proteins in PD and their interplay with both αsyn and LRRK2. We have observed that 14-3-3θ acts as a chaperone to reduce αsyn aggregation and cell-to-cell transmission, and this same 14-3-3 isoform reduces the kinase activity and toxicity of mutant LRRK2. While our data clearly points to a potentially critical role for 14-3-3 dysfunction in Parkinson’s disease, a key question that remains is how 14-3-3θ’s endogenous functions could become impaired in PD. We propose that aberrant phosphorylation of 14-3-3θ is the critical pathophysiologic event, and that increases in 14-3-3θ phosphorylation promotes LRRK2 and αsyn effects in disease. In support of this hypothesis, we recently published data showing that 14-3-3θ phosphorylation at S232 is dramatically elevated in the detergent-insoluble fractions from human PD and DLB brains. This increase in S232 phosphorylation correlates with cognitive decline and pathological severity measures, consistent with a role of S232 phosphorylation in the pathogenesis of neurodegeneration. In addition, we have observed that mitochondrial stress promotes 14-3-3θ phosphorylation at S232 in culture. The S232D phosphomimetic mutant loses its protective effects in neurotoxin and αsyn culture models. Based on these data, we hypothesize that oxidative stress is a key upstream inducer of excessive 14-3-3θ phosphorylation, leading to αsyn and LRRK2 toxicity. We recently created a conditional knock-in (KI) 14-3-3θ S232D mouse line that will serve as the critical tool to understand the impact of 14-3-3 phosphorylation in PD. In Aim 1, we will test how 14-3-3θ phosphorylation alters interactions with αsyn and modulates subsequent αsyn pathology. In Aim 2, we will test the impact of 14-3-3 phosphorylation on its interaction with LRRK2 and LRRK2 function. In Aim 3, we will examine whether 14-3-3θ phosphorylation occurs early in sporadic PD and whether oxidative stress mediates toxicity via excessive 14-3-3 phosphorylation.

项目摘要 与帕金森氏病（PD）相关的两种关键蛋白质是α-核蛋白（αSyn）和LRRK2。突变 一个基因引起PD的常染色体显性形式，而GWAS研究指出了这两个基因的变异 作为开发特发性PD的风险因素。尽管两种蛋白质都会带来类似的病理结果，但如何 这两种蛋白质会导致神经元损伤及其在疾病过程中的相互作用尚未得到很好的了解。 我们的关键发现是14-3-3θ是αSyn和LRRK2的主要调节剂，可能是缺失的链接 在αSyn和lrrk2之间。 14-3-3s是多功能的高表达脑蛋白，充当伴侣， 影响蛋白质运输，并调节其结合伴侣的酶活性。我们的研究强调了 这些临界蛋白在PD及其与αSyn和LRRK2的相互作用的作用。我们已经观察到 14-3-3θ充当伴侣，以减少αSyn聚集和细胞向细胞传输，并且相同的14-3-3 同工型降低突变LRRK2的激酶活性和毒性。 虽然我们的数据清楚地表明了14-3-3功能障碍在帕金森氏病中的潜在至关重要的作用，这是关键 剩下的问题是14-3-3θ的内源性功能如何在PD中受到损害。我们提出了这一点 14-3-3θ的异常磷酸化是关键的病理生理事件，它在14-3-3θ中增加 磷酸化促进LRRK2和αSyn对疾病的影响。为了支持这一假设，我们最近 已发表的数据表明，在检测器 - 不溶于验证器中，S232处的14-3θ光年化显着升高 人类PD和DLB大脑的馏分。 S232磷酸化的这种增加与认知相关 衰落和病理严重程度测量，与S232磷酸化在发病机理中的作用一致 神经变性。此外，我们观察到线粒体应力促进14-3-3θ 培养中S232处的磷酸化。 S232D磷酸化突变体在神经毒素中失去了保护作用 和αsyn培养模型。 基于这些数据，我们假设氧化应激是超过14-3-3θ的关键上游诱导剂 磷酸化，导致αSyn和LRRK2毒性。我们最近创建了一个有条件的敲门（KI）14-3-3θ S232D小鼠系列将作为了解PD中14-3-3磷酸化的影响的关键工具。 在AIM 1中，我们将测试14-3θ光磷酸化如何改变与αSyn的相互作用并调节随后的αSyn 病理。在AIM 2中，我们将测试14-3-3磷酸化对其与LRRK2和LRRK2相互作用的影响 功能。在AIM 3中，我们将检查14-3-3θ磷酸化是否发生在零星PD中，以及是否发生 氧化应激通过过量的14-3-3磷酸化介导毒性。