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-核蛋白（αs）的神经元聚集是钥匙的标志 阿尔茨海默氏病和相关疾病（ADRDS），包括Lewy身体痴呆（LBD）， 帕金森氏病（PDD）和混合AD/LB痴呆症。集体这些 疾病会影响数百万美国公民。理解αs毒性的机制，因此保持关键 导入理解和治疗ADRD。 αs可逆地与细胞膜相关联 在神经元和这种相互作用中，对毒性显然很重要，但是潜在的机制 保持不清楚。此外，αs在细胞质中也很丰富。 αs在不同的 细胞隔室以及当α异常时与神经毒性有关 在ADRD中积累仍然未知。我们以前的广泛遗传和物理α 连接αs的相互作用映射不仅与膜运输蛋白，而且还与A RNA结合蛋白（RBP）的惊人数量。但是，虽然RBP失调和损失 RNA的稳态显然是神经变性的重要贡献者，这是直接的 到目前为止，αs和RBP之间的链接难以捉摸。我们最近发现α可以扰动RNA 稳态直接与在 加工体，无膜核糖核蛋白复合物，负责mRNA转换。 αs与神经元中P-bodies的蛋白质的蛋白质强烈相互作用。重要的是，完全一样 （N末端）αS区域负责与膜和P体蛋白结合。这是 建立二分关系，从而在膜上改变可以直接影响基因 通过在膜和胞质室之间重新分布α来调节。在 我们在人IPSC神经元和死后大脑中的发现的基础，我们假设αs 膜和P体之间的班车，并且在积累到有毒水平时，会破坏P- 身体成分和mRNA更新。模型有机体和人类遗传学分析 支持P体途径在调节αS毒性的PD风险中的因果影响。在这里，我们 首先，将通过测量广泛的P体扰动来严格测试这些连接 肌醇模型，验尸大脑和小鼠模型，并评估 p体基因神经毒性。其次，我们将研究哪些特定的mRNA转录本和 mRNA的亚类受到αs积累或突变的影响。最后，我们将调查 αS如何调节完全体外重构系统中的酶学和组成。 我们预计这项研究将揭示RNA稳态破坏是路易的关键方面 身体疾病的发病机理并激发了ADRD的新治疗策略。