Probes to differentiate AD brain beta-amyloid from model beta-amyloid systems

区分 AD 大脑 β-淀粉样蛋白与模型 β-淀粉样蛋白系统的探针

基本信息

批准号：
8581545
负责人：
HARRY LEVINE
金额：
$ 22.5万
依托单位：
UNIVERSITY OF KENTUCKY
依托单位国家：
美国
项目类别：
财政年份：
2013
资助国家：
美国
起止时间：
2013-07-01 至 2015-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8581545
关键词：
Acetylene Affect Affinity Affinity Chromatography Alkynes Alzheimer&apos s Disease Amyloid beta-Protein Animal Model Animals Azides Binding Binding Sites Biochemical Biological Models Biotin Brain Brain Mass Carbohydrates Cessation of life Characteristics Chemistry Complex Congo Red Copper Couples Data Dementia Disease Drug Design Drug Targeting Etiology Goals Histologic Human Image In Vitro Libraries Ligand Binding Ligands Lipids Mass Spectrum Analysis Modeling Neurons Parents Phase Phospholipids Photoaffinity Labels Pittsburgh Compound-B Property Proteins Proteomics Radioisotopes Reaction Research Research Personnel Resistance Series Staging Streptavidin Structure Synaptosomes System Techniques Temperature Thioflavin S Work adduct amyloid pathology analog beta amyloid pathology cycloaddition design human disease in vivo innovation insight interest new therapeutic target novel particle public health relevance reconstitution scaffold stoichiometry thioflavine

项目摘要

DESCRIPTION (provided by applicant): Animal models of Alzheimer's disease (AD) recapitulate early phases of the human condition, but not the later stages of neuronal death and dementia. These models develop histologically similar, but distinguishable A beta amyloid pathology. The imaging ligand Pittsburgh Compound B (PIB) binds insoluble A beta from human, animal and synthetic systems with nM affinity. However, the stoichiometry of PIB binding to human AD brain is approximately 500- to 10,000-fold greater than that in animal models or synthetic A beta fibrils. Other A beta ligands such as Thioflavin S and Congo Red do not discriminate between human, animal, and synthetic A beta fibrils. We hypothesize that the difference in PIB binding between human brain and animal A beta fibrils is integral to the mechanism of neuronal death and dementia in human AD, and contributes to the lack of complete recapitulation of the disease in animal models. Preliminary data indicate that uncharacterized biochemical components in addition to A beta are required for the high binding stoichiometry of PIB in AD brain, which resides in a denaturation-resistant assembly. The proposed work will generate photoaffinity probes for the human A beta PIB binding site that also contain a tag to enable affinity purification and we will utilize these probes to affinity isolate nd identify protein and lipid components contacting the PIB ligand in the AD brain by mass spectral analysis. Specific Aim 1. Synthesize and optimize a series of photoaffinity ligands with handles for affinity tags that are selective for the PIB binding site of human AD brain. Specific Aim 2. Identify the protein and lipid components that form the PIB ligand binding site of AD brain using MR-PIB and mass spectrometry. The long term goal of this project is to use the identified components and structure of the human AD A beta fibril and its PIB ligand binding pocket to provide insight into unique properties of human AD A beta assemblies that contribute to AD. Ultimately we will determine the differences between human and AD animal models A beta assemblies to elucidate AD-related cellular and environmental mechanisms that will inform the improvement of animal models and identify potential novel drug targets.

描述（由申请人提供）：阿尔茨海默病（AD）的动物模型重现了人类疾病的早期阶段，但没有重现神经元死亡和痴呆的后期阶段。这些模型形成组织学相似但可区分的 Aβ 淀粉样蛋白病理学。成像配体匹兹堡化合物 B (PIB) 以 nM 亲和力结合来自人类、动物和合成系统的不溶性 Aβ。然而，PIB 与人类 AD 大脑结合的化学计量比动物模型或合成 A β 原纤维中的化学计量高约 500 至 10,000 倍。其他 A β 配体（例如硫磺素 S 和刚果红）不会区分人类、动物和合成 A β 原纤维。我们假设人脑和动物 A β 原纤维之间 PIB 结合的差异是人类 AD 中神经元死亡和痴呆机制不可或缺的一部分，并导致动物模型中缺乏对该疾病的完整重现。初步数据表明，AD 脑中 PIB 的高结合化学计量需要除 Aβ 之外的未表征的生化成分，PIB 存在于抗变性组装体中。拟议的工作将为人类 A beta PIB 结合位点生成光亲和探针，该探针还包含一个标签以实现亲和纯化，我们将利用这些探针进行亲和分离，并通过质谱鉴定与 AD 脑中 PIB 配体接触的蛋白质和脂质成分分析。具体目标 1. 合成并优化一系列带有亲和标签手柄的光亲和配体，这些配体对人 AD 脑的 PIB 结合位点具有选择性。具体目标 2. 使用 MR-PIB 和质谱法鉴定形成 AD 大脑 PIB 配体结合位点的蛋白质和脂质成分。该项目的长期目标是利用已确定的人类 AD A β 原纤维及其 PIB 配体结合袋的成分和结构，深入了解导致 AD 的人类 AD A β 组装体的独特特性。最终，我们将确定人类和 AD 动物模型 A beta 组件之间的差异，以阐明 AD 相关的细胞和环境机制，从而为动物模型的改进提供信息并确定潜在的新药物靶点。