Investigating physiologic and pathophysiologic connections between the Parkinson's disease protein alpha-synuclein and RNA binding proteins

研究帕金森病蛋白 α-突触核蛋白和 RNA 结合蛋白之间的生理和病理生理联系

• 批准号: 10744556
• 负责人: Vikram Khurana
• 金额: $ 83.13万
• 依托单位: BRIGHAM AND WOMEN'S HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-08-01 至 2028-07-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10744556
• 关键词: Affect; Alzheimer' s disease related dementia; Autopsy; Binding; Biological Assay; Biology; Body Composition; Brain; CRISPR interference; CRISPR/Cas technology; Cellular Membrane; Complex; Cytoplasmic Granules; Cytosol; Data; Dementia with Lewy Bodies; Disease; Enzymatic Biochemistry; Enzymes; Exonuclease; Functional disorder; Gene Expression Regulation; Genes; Genetic; Homeostasis; Human; Human Genetics; Impaired cognition; In Vitro; Induced pluripotent stem cell derived neurons; Investigation; Knowledge; Lead; Left; Lesion; Lewy Bodies; Lewy Body Dementia; Lewy Body Disease; Link; Maps; Measures; Membrane; Membrane Proteins; Messenger RNA; Metabolism; Modeling; Mutation; Nerve Degeneration; Neurons; Parkinson Disease; Parkinson' s Dementia; Pathogenesis; Pathology; Pathway Analysis; Pathway interactions; Patients; Physiological; Point Mutation; Protein Biosynthesis; Proteins; Publications; RNA; RNA Interference; RNA-Binding Proteins; Research; Ribonucleoproteins; Risk; Role; SNCA gene; Sampling; Surveys; System; Testing; Toxic effect; Transcript; alpha synuclein; clinically significant; decapping enzyme; dopaminergic neuron; experimental study; genetic analysis; induced pluripotent stem cell; knock-down; mRNA Decay; mRNA decapping; model organism; mouse model; neurotoxicity; novel; novel therapeutic intervention; prevent; prospective; protein aggregation; protein function; protein transport; reconstitution; response; scaffold; sporadic Parkinson' s Disease; synucleinopathy; tau Proteins; therapeutic target; trafficking; translation factor

Neuronal aggregation of the protein alpha-synuclein (αS) in Lewy bodies is a hallmark of key Alzheimer Disease and Related Disorders (ADRDs) including Lewy Body Dementia (LBD), Parkinson’s disease with dementia (PDD) and mixed AD/LB dementia. Collectively these disorders affect millions of US citizens. Understanding mechanisms of αS toxicity thus holds key import for understanding and treating ADRD. αS reversibly associates with cellular membranes in neurons and this interaction is clearly important for toxicity, but the underlying mechanisms remain unclear. Moreover, αS is also highly abundant in the cytosol. What αS is doing in different cellular compartments and how this may be relevant to neurotoxicity when αS abnormally accumulates in ADRD remains unknown. Our previous extensive genetic and physical αS interaction mapping connected αS not only to membrane trafficking proteins but also to a surprising number of RNA-binding proteins (RBPs). However, while RBP dysregulation and loss of RNA homeostasis are clearly important contributors to neurodegeneration in general, a direct link between αS and RBPs was elusive until now. We recently found that αS can perturb RNA homeostasis by directly interacting with and disrupting the mRNA decapping machinery found in Processing Bodies, membraneless ribonucleoprotein complexes responsible for mRNA turnover. αS strongly interacts with decapping proteins of P-bodies in neurons. Importantly, the exact same (N-terminus) αS region is responsible for binding to membranes and to P-body proteins. This sets up a dichotomous relationship whereby alterations at the membrane can directly affect gene regulation through redistributing αS between membrane and cytosolic compartments. On the basis of our findings in human iPSC neurons and postmortem brain, we hypothesize that αS shuttles between membranes and P-bodies and, upon accumulation to toxic levels, disrupts P- body composition and mRNA turnover. Model organism and human genetics analyses also support a causal influence of the P-body pathway in modulating αS toxicity an PD risk. Here, we will, first, rigorously test these connections by measuring P-body perturbations in a wide-range of synucleinopathy models, postmortem brain and mouse models and assess the direct impact of P-body genes on neurotoxicity. Second, we will investigate which specific mRNA transcripts and subclasses of mRNAs are impacted by αS accumulation or mutation. Finally, we will investigate how αS modulates decapping enzymology and composition in a fully in vitro reconstituted system. We anticipate that this study will reveal that RNA homeostasis disruption is a key aspect of Lewy body disease pathogenesis and motivate new treatment strategies for ADRD.

路易体中蛋白质 α-突触核蛋白 (αS) 的神经元聚集是关键的标志 阿尔茨海默病及相关疾病 (ADRD)，包括路易体痴呆 (LBD)、 帕金森病伴痴呆 (PDD) 和混合性 AD/LB 痴呆。 因此，了解 αS 毒性的机制至关重要。 对于理解和治疗 ADRD 具有重要意义。 在神经元中，这种相互作用显然对毒性很重要，但潜在的机制 此外，αS 在细胞质中的含量也很高。 细胞区室以及当 αS 异常时这与神经毒性的关系 我们之前广泛的遗传和身体αS在ADRD中的积累仍然未知。 相互作用作图不仅将 αS 连接到膜运输蛋白，而且还连接到 然而，RNA 结合蛋白 (RBP) 的数量惊人，但 RBP 却失调和丢失。 RNA稳态的变化显然是神经退行性变的重要贡献者，是神经退行性疾病的直接影响因素。 到目前为止，αS 和 RBP 之间的联系还难以捉摸，我们最近发现 αS 可以扰乱 RNA。 通过直接相互作用并破坏 mRNA 脱帽机制来实现体内平衡 加工体，负责 mRNA 周转的无膜核糖核蛋白复合物。 αS 与神经元中 P 体的脱帽蛋白强烈相互作用。 （N 末端）αS 区域负责与膜和 P 体蛋白结合。 建立二分关系，膜的改变可以直接影响基因 通过在膜和胞质区室之间重新分配 αS 进行调节。 根据我们在人类 iPSC 神经元和死后大脑中的发现，我们追求 αS 在膜和 P-体之间穿梭，当积累到毒性水平时，会破坏 P-体 身体成分和 mRNA 更新也进行分析。 在此，我们支持 P 体途径在调节 αS 毒性和 PD 风险中的因果影响。 首先，将通过测量各种 P 体扰动来严格测试这些连接 突触核蛋白病模型、死后大脑和小鼠模型，并评估 其次，我们将研究哪些特定的 mRNA 转录物和 P-body 基因对神经毒性的影响。 mRNA 的亚类受到 αS 积累或突变的影响。 αS 如何在完全体外重构的系统中调节脱盖酶学和成分。 我们预计这项研究将揭示 RNA 稳态破坏是 Lewy 的一个关键方面 身体疾病发病机制和动机 ADRD 的新治疗策略。