Structural Study of Tau and Binding Partners

细胞骨架基础结构是细胞生命的基本过程，如：运动、分裂、形态和细胞内运输。细胞骨架的微管(MT)成分是一种固有的动态结构，但在一些人的神经系统中，MT保持了100多年的稳定。稳定的MTS既维持突触连接，又作为突触功能所需的细胞内运输的高速公路。这些过程对衰老的影响很敏感，并且随着时间的推移与功能性突触的丧失有关。此外，细胞骨架的改变是阿尔茨海默氏症和帕金森氏症等神经退行性疾病的特征，这些疾病通常在晚年表现出来。这项建议的研究旨在获得参与在MT高速公路上稳定和运输的蛋白质的一些第一个结构特征。Tau蛋白被神经元用来稳定其MTS，也是与阿尔茨海默病相关的两种主要蛋白质沉积之一。从历史上看，由于tau的构象灵活性，一直缺乏关于tau的结构信息。这里的方法是解决tau与MAP结合的结构，这将使tau锁定在单一构象中，并绕过微管蛋白的聚集倾向。这些结构信息将补充其他研究，并提供一个连贯的结构框架，以了解不同构象状态的tau和微管之间的相互作用，为药物设计和预防或纠正tau沉积提供新的场所。目前，关于MTS和细胞内转运之间的相互作用缺乏结构信息。我建议启动对几个额外的MT结合域的研究，以便在分子水平上阐明微管成核、生长、减少、切断、稳定和调节所涉及的相互作用，这些都是细胞内运输所必需的。

The cytoskeletal infrastructure underlies fundamental processes of cellular life such as: motility, division, morphology, and intracellular transport. The microtubule (MT) component of the cytoskeleton is an inherently dynamic structure and yet the MTs are stabilized for more than 100 years within the nervous system of some individuals. The stabilized MTs both maintain synaptic connections and serve as a highway for the intracellular transport required for synapsis function. These processes are sensitive to the effects of aging and correlated with the loss of functional synapsis over time. Additionally, alterations of the cytoskeleton are characteristic to neurodegenerative diseases such as Alzheimer's and Parkinson's disease, which typically manifest later in life. The research in this proposal is aimed at obtaining some of the first structural characterization of the proteins involved in stabilizing and trafficking upon the MT highway. The protein tau is used by neurons to stabilize its MTs and is also one of two major protein deposits associated with Alzheimer's disease. Historically, structural information on tau has be lacking due to its conformational flexibility. The approach here is to solve the structure of tau bound to mapmodulin, which will lock tau into a single conformation and circumvent the aggregation tendencies of tubulin. The structural information will complement other studies and provide a coherent structural framework for understanding the interactions between the different conformational states of tau and microtubules providing new venues for drug design and the prevention or correction of tau deposition. Currently there is an absence of structural information regarding interactions between MTs and intracellular transport. I propose to initiate studies on several additional MT binding domains in order to clarify at the molecular level the interactions involved in microtubule nucleation, growth, reduction, severing, stabilization, and regulation, that are required for intracellular transport.