Physical Biochemistry and Biology of Amyloid Beta-Protein

描述（由申请人提供）：阿尔茨海默病（AD）是一种严重危害老年人的疾病。两种淀粉样蛋白形成蛋白与AD相关，淀粉样蛋白ß-蛋白（ß）和tau蛋白。最近的证据支持一种假说，即“淀粉样蛋白级联假说”，该假说认为亚ß寡聚物是阿尔茨海默病的精神经致病因子。本提案的总体目标是了解asas及其片段的结构生物学，并建立正式的结构-活性关系。从长远来看，我们寻求获得由asas形成的邻近神经毒素结构的原子分辨率测定，并在此过程中，首次实现疾病修饰性AD治疗的发展。将采用多学科策略，采用互补的实验和计算方法。这一策略在过去被非常成功地使用过，为asass系统提供了新的见解。提出了三个具体的目标，系统地和逻辑地从体外对asas及其寡聚物的生物物理研究（目标1），到体外和体内对选定的这些组装物的生物活性研究（目标2），再到确定选定的组装物对神经元中差异基因表达的影响（目标3）。综上所述，这些研究将为后续治疗性化合物的开发和人体临床试验提供理论和实验基础。目的1。确定阿斯和陶组装的结构动力学。a.利用扫描Tyr诱变来阐明亚ß寡聚化的机制。b.确定分子内转弯形成的动力学及其对ass组装的影响。c.确定初级结构变化对生物相关和理论上重要的α -肽的构象和组装动力学的影响。目标2。目的：确定亚氏组装体的生物学效应。a.确定asas组装体对培养的神经细胞系和原代神经元的细胞毒性作用。b.确定asas组件对果蝇眼睛发育、运动和寿命的影响。目标3。利用生物信息学方法识别和验证ad相关基因，该方法考虑了asas组装结构、神经元类型和神经元衰老。

DESCRIPTION (provided by applicant): Alzheimer's disease (AD) is a devastating disease of the aged. Two amyloid-forming proteins are associated with AD, the amyloidß-protein (Aß) and tau. Recent evidence supports an hypothesis, the "amyloid cascade hypothesis," that posits that Aß oligomers are the seminal neuropathogenetic agents in AD. The overall goal of this proposal is to understand the structural biology of Aß, and fragments thereof, and to establish formal structure-activity relationships. In the long run, we seek to obtain an atomic-resolution determination of the structure of the proximate neurotoxins formed by Aß, and in doing so, enable the development, for the first time, of disease-modifying AD treatments. A multidisciplinary strategy, employing complementary experimental and computational approaches, will be employed. This strategy has been used very successfully in the past, providing novel insights into the Aß system. Three specific aims are proposed that systematically and logically progress from in vitro biophysical studies of Aß and its oligomeric assemblies (Aim 1), to in vitro and in vivo studies of the biological activity of selected such assemblies (Aim 2), to determination of the effects of selected assemblies on differential gene expression in neurons (Aim 3). Taken together, these studies will provide the theoretical and experimental foundation for subsequent therapeutic compound development and clinical testing in humans. Aim 1. To determine the structural dynamics of Aß and tau assembly. a. To use scanning Tyr mutagenesis to elucidate mechanisms of Aß oligomerization. b. To determine the dynamics of intramolecular turn formation and its effects on Aß assembly. c. To determine the effects of primary structure changes on the conformations and assembly dynamics of biologically relevant and theoretically important Aß peptides. Aim 2. To determine the biological effects of Aß assemblies. a. To determine the cytotoxic effects of Aß assemblies on cultured neuronal cell lines and primary neurons. b. To determine the effects of Aß assemblies on Drosophila eye development, locomotion, and longevity. Aim 3. To identify and validate AD-relevant genes using a bioinformatics approach that considers Aß assembly structure, neuron type, and neuron senescence.