Capturing the molecular complexity of tau pathology-associated proteomes involved in the etiology of Alzheimer's disease and related dementias

项目总结/摘要 该项目的目标是捕获病理性tau相关蛋白的分子复杂性， 阿尔茨海默病（AD）和相关tau蛋白病患者的大脑，并获得一个全面的 对它们在tau病理学和相关神经变性的进展中的作用的机械理解。 先前的研究表明微管的特征性时间和拓扑模式的相关性- 相关蛋白tau（MAPT）聚集与观察到的临床表型和进展， 疾病虽然神经纤维缠结（NFT）和其他形式的磷酸化tau聚集体被认为是 在疾病过程中起着举足轻重的作用，我们对它的组成和分子水平了解甚少。 这些不溶性聚集体的环境，以及它们的形成，毒性和在大脑中的传播 区域是规范的。更好地了解AD和原发性tau蛋白病中的磷酸化tau相互作用组， 以及这些蛋白质如何调节受影响的tau蛋白的寡聚化、病理性积累和播种， 神经元和神经胶质对于鉴定新的治疗靶点至关重要。 作为当前技术的限制，NFT和其他神经病理学的深入表征是不可能的。 夹杂物历来难以处理，因为这些聚集体是不溶于洗涤剂的， 对经典的亲和纯化方法是难处理的。为了解决这个问题，我们建立了一个新的 用于邻近标记、纯化和鉴定病理性磷酸化tau相关蛋白的方法 从固定的人体组织中提取蛋白质，然后进行定量蛋白质组学分析。 我们假设病理性tau聚集体的分子环境有助于AD 疾病过程，并建议使用最新的尖端技术来确定和比较 不同患者队列和疾病阶段的磷酸化tau相关蛋白质组，以破译分子 信号网络在疾病发展中的作用，并在功能上验证人类AD的新治疗靶点 病例、小鼠模型和人类类器官模型。我们的三个具体目标是：（i）比较tau病理学- 通过邻近蛋白质组学研究常见的tau蛋白病中的磷酸化tau蛋白包涵体， AD和原发性tau蛋白病患者的脑，（ii）建立tau病理学的时空模式- AD患者队列中疾病阶段、脑区和脑弹性特异性相关蛋白质组， 以及（iii）确定tau病理学相关蛋白在神经变性过程中的功能作用 在人类AD病例、小鼠模型和人脑类器官中。 成功完成这个项目将确定新的分子成分和细胞途径 调节AD和原发性tau蛋白病的发病机制，这可能为AD的治疗提供新的策略。 有效治疗这些毁灭性的疾病。

PROJECT SUMMARY/ABSTRACT The goal of this project is to capture the molecular complexity of pathological tau-associated proteins in the brain of Alzheimer’s disease (AD) and related tauopathy patients via proximity-proteomics and gain a thorough mechanistic understanding of their role in the progression of tau pathology and associated neurodegeneration. Previous studies suggest a correlation of characteristic temporal and topological patterns of microtubule- associated protein tau (MAPT) aggregates with the observed clinical phenotype and the progression of the disease. Although neurofibrillary tangles (NFTs) and other forms of phospho-tau aggregates are believed to play a pivotal role in the disease process, we have a poor understanding of the composition and molecular environment of these insoluble aggregates, and how their formation, toxicity, and spread across the brain regions is regulated. A better understanding of the phospho-tau interactome in AD and primary tauopathies, and how these proteins regulate the oligomerization, pathological accumulation, and seeding of tau in affected neurons and glia is of critical importance for the identification of novel therapeutic targets. As a limitation of current technologies, the in-depth characterization of NFTs and other neuropathologic inclusions has historically been difficult to address, since these aggregates are detergent-insoluble, and thus refractory to classical affinity purification methods. To address this limitation, we have established a novel method for the proximity-labeling, purification and identification of pathological phospho-tau associated proteins from fixed human tissue followed by quantitative proteomics analysis. We hypothesize that the molecular environment of pathological tau aggregates contributes to the AD disease process and propose to use the latest cutting-edge technologies to determine and compare the phospho-tau associated proteome across different patient cohorts and disease stages, to decipher molecular signaling networks in disease development, and to functionally validate novel therapeutic targets in human AD cases, mouse models, and human organoid models. Our three specific aims are: (i) to compare tau pathology- associated proteomes across common tauopathies via proximity proteomics of phospho-tau inclusions in the brain of AD and primary tauopathy patients, (ii) to establish spatiotemporal patterns of tau pathology- associated proteomes specific for disease stages, brain regions, and brain resilience in AD patient cohorts, and (iii) to determine the functional role of tau pathology-associated proteins in neurodegenerative processes in human AD cases, mouse models, and human brain organoids. Successful completion of this project will identify novel molecular components and cellular pathways regulating the pathogenesis of AD and primary tauopathies, which may provide new therapeutic strategies for effective treatment of these devastating disorders.