Deciphering the Molecular Features Underlying LRP1-Mediated Tau Spread

一些神经退行性疾病，如阿尔茨海默病(AD)，其特点是扩散和 蛋白tau的聚集。最近，我们发现了一种细胞受体，LRP1(低密度脂蛋白 受体相关蛋白1)，调节tau的传播途径。LRP1基因敲除可阻止tau扩散 在人类iPS神经元和小鼠脑中，表明tau-LRP1相互作用可能是一个重要的 疾病干预的切入点。不幸的是，对tau-LRP1分子复合体的详细了解 仍然是缺乏的。因此，本项目的主要目标是定义tau-LRP1结构界面和 了解对tau结构的翻译后修饰(PTM)如何影响tau的吸收和扩散。在……里面 前期工作，我们已经开发了纯化和测量tau和LRP1之间相互作用的协议。我们 已经建立了蜂窝平台来模拟tau的传播，并已经表明这个过程可以受到影响 由Tau PTMS提供。为了充分开展这项工作，我们提出了三个目标。在目标1中，我们将使用tr-fret在 Tau和LRP1之间的体外亲和力和质谱图蛋白质-蛋白质界面。在目标2中，我们 我将研究tau磷酸化如何影响tau-lrp1复合体，以及这对tau扩散有什么影响。 和聚合。在目标3中，我们将重点介绍改变赖氨酸残基的tau PTM。我们将评估泛素化是否 或者乙酰化可以影响tau-LRP1的相互作用，如果它们影响tau聚集，如果它们促进或抑制 Tau在细胞中的摄取和种植。创新的实验方法和综合分析概述 这将提供重要的机制洞察力，并发展我们对致病tau调控的理解。 广告。这将是开发和评估潜在的阿尔茨海默病治疗方法的重要第一步。

Several neurodegenerative diseases, such as Alzheimer’s disease (AD), are characterized by the spread and aggregation of the protein tau. Recently, we identified a cellular receptor, LRP1 (Low-density lipoprotein Receptor-related Protein 1), that regulates the tau spread pathway. Knockdown of LRP1 prevents tau spread in human iPS neurons and the mouse brain, suggesting that the tau-LRP1 interaction could be an important entry point for disease intervention. Unfortunately, a detailed understanding of the tau-LRP1 molecular complex is still lacking. Therefore, the main objective of this project is to define the tau-LRP1 structural interface and discern how post-translation modifications (PTMs) to tau’s structure influence tau uptake and spread. In preliminary work, we have developed protocols to purify and measure interactions between tau and LRP1. We have established cellular platforms to model tau propagation and have shown that this process can be influenced by tau PTMs. To fully develop this work, we propose three aims. In Aim 1, we will use TR-FRET to establish in vitro affinities between tau and LRP1 and mass spectrometry to map the protein-protein interface. In Aim 2, we will look at how tau phosphorylation can influence the tau-LRP1 complex and what effect this has on tau spread and aggregation. In Aim 3, we will focus on tau PTMs that alter lysine residues. We will assess if ubiquitination or acetylation can impact the tau-LRP1 interaction, if they influence tau aggregation, and if they promote or inhibit tau uptake and seeding in cells. The innovative experimental methods and comprehensive analyses outlined herein will provide important mechanistic insight and develop our understanding of pathogenic tau regulation in AD. This will be an essential first step forward for the development and evaluation of potential AD therapeutics.