Regulation and Function of Gamma-Secretase

描述（由申请人提供）：本提案的目的是阐明内源性γ-分泌酶的调节，了解阿尔茨海默病（AD）的潜在机制，并为药物开发提供分子基础。γ-分泌酶作为阿尔茨海默病和癌症的药物靶点已被广泛研究。目前关于γ-分泌酶的大多数知识主要来自在细胞模型中使用γ-分泌酶的一种或多种组分的外源表达的研究。不同的γ-分泌酶复合物和底物特异性是否与细胞类型相关，可能与细胞谱系和组织相关，目前还知之甚少。拟开展的研究将探讨内源性γ-分泌酶复合物的调节和功能。本申请的第一个目的是阐明γ-分泌酶活性和特异性在上皮、造血神经元起源中的机制。第二个具体目标是检查γ-分泌酶复合物内的活性位点的形状，并确定从上皮细胞系、造血细胞系和神经元细胞系分离的γ-分泌酶复合物的化学计量。最后，第三个目的是确定PS1突变敲入中γ-分泌酶活性的机制和特异性，并分析活性位点结构和复合物组成。拟议的研究将全面了解内源性γ-分泌酶，并提供γ-分泌酶的结构和功能的见解，并可能导致更好地了解γ-分泌酶在AD和癌症以及开发更有效的治疗AD，恶性肿瘤和其他人类疾病。

DESCRIPTION (provided by applicant): The objectives of this proposal are to elucidate the regulation of endogenous gamma-secretase and to understand the mechanism underlying Alzheimer's disease (AD) as well as to provide a molecular basis of drug development. gamma-Secretase as a drug target for Alzheimer's disease and cancer has been extensively investigated. Most of knowledge today on gamma-secretase mainly comes from studies that used an exogenous expression of one or more of the components of gamma-secretase in cellular models. Whether distinct gamma-secretase complexes and substrate specificity are associated with cell types, and possibly cell lineage and tissues is poorly understood. The proposed studies will investigate the regulation and function of the endogenous gamma-secretase complexes. The first aim of this application is to elucidate the mechanism of gamma-secretase activity and specificity in epithelial, hematopoietic neuronal origins. The second specific aim is to examine the shape of the active site within the gamma-secretase complex and determine the stoichiometry of the gamma-secretase complexes isolated from epithelial, hematopoietic and neuronal cell lines. Lastly, the third aim is to determine the mechanism and specificity of gamma-secretase activity in the PS1 mutation knock-in and analyze active site structure and complex composition. The proposed studies will develop a comprehensive understanding of endogenous gamma-secretase and provide insights into the structure and function of gamma-secretase and may lead to a better understanding of gamma-secretase in AD and cancer as well as the development more effective treatment for AD, malignancies and other human disorders.