Investigating the synaptic pathology of Autism

研究自闭症的突触病理学

基本信息

批准号：
10053341
负责人：
Stephen Edward Paucha Smith
金额：
$ 54.53万
依托单位：
SEATTLE CHILDREN'S HOSPITAL
依托单位国家：
美国
项目类别：
财政年份：
2017
资助国家：
美国
起止时间：
2017-12-01 至 2022-10-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10053341
关键词：
Acute Affect Agonist Animal Model Animals Behavior Behavioral Binding Characteristics Chemicals Chemosensitization Co-Immunoprecipitations Complex DNA Sequence Alteration Data Disease Drug Targeting Equilibrium Feedback Fragile X Syndrome Gene Mutation Gene Proteins Genes Genetic Models Genetic study Glutamate Receptor Glutamates Goals Homeostasis Knock-out Link Longevity Measurement Metabotropic Glutamate Receptors Modeling Molecular Morphology Mutation N-Methyl-D-Aspartate Receptors N-Methylaspartate Neurodevelopmental Disorder Neurons Organism Output Pathogenesis Pathologic Pathology Pattern Pharmaceutical Preparations Physiological Process Protein Engineering Proteins Publishing Risk Science Signal Transduction Slice Stereotyping Structure Synapses System Technology Testing Therapeutic Translating UBE3A gene Variant autism spectrum disorder base design gene product graph theory in vitro Assay information processing insight kinase inhibitor link protein mathematical model member mouse model network models new technology novel overexpression predictive modeling protein complex protein function response scaffold small molecule stem synaptic function targeted treatment therapeutic target tool transmission process vector

项目摘要

PROJECT SUMMARY Genetic mutations that confer autism risk often occur in genes that are expressed at the glutamate synapse. The protein products of these genes form a highly interconnected protein interaction network (PIN), and represent attractive therapeutic targets since they are expressed throughout the lifespan and can be acutely targeted with small molecule drugs. However, the dynamic, network-scale behavior of this PIN in normal or disease states is poorly understood. Here, we apply a novel PIN-mapping technology, quantitative multiplex co-immunoprecipitation, to explore the input-output relationships of an autism-linked PIN at the glutamate synapse as it responds to physiological inputs. Our target system is a 20-member PIN, consisting of glutamate receptors, scaffolds, and signal transduction molecules; mutations in the genes encoding all target proteins have been genetically linked to autism. We first show that, in wild-type animals, our target PIN changes its pattern of co-associations in a stereotyped manner in response to acute stimulation with KCl or glutamate, using cultured neurons or acute slices. We then model the input-output relationships of the PIN system, and demonstrate that the PIN produces specific, recognizable signatures in response to stimulation through the mGluR or NMDA receptors. In the context of physiological glutamate stimulation, the PIN integrates the two inputs to produce a coordinated cellular response- potentiation or de-potentiation. Based on these and other preliminary observations and published data, we propose that mutations that contribute to autism risk disrupt information flow through this PIN, such that the balance between LTP-like potentiation and LTD-like depotentiaion is altered, ultimately leading to an organism-level imbalance between excitation and inhibition. We will test this hypothesis by modeling the PIN response to mGluR or NMDA stimulation in three distinct, well-characterized animal models of autism- the Fragile X knockout, Shank3 knockout, and Ube3a overexpressing models. We will characterize the input-output relationships for mGluR or NMDA stimulation, and mathematically model their integration using a vector transformation model in principal component space. We will define specific mechanisms by which autism-linked mutations disrupt either input-output relationships, or disrupt signal integration in the context of physiological stimulation. In addition, we will treat two of our animal models (Shank3 and Fragile X) with drugs that have been previously demonstrated to rescue autism- like behaviors. We will model the response of the PIN to the drug with or without concurrent stimulation to define a PIN signature associated with behavioral rescue. In summary we propose to (1) define normal information flow through a PIN consisting of the protein products of autism-liked genes; (2) define how information flow is disrupted in mouse models of autism, with the goal of understanding the system sufficiently to design targeted drug treatments and (3) define how the PIN responds to drugs that correct behavior, which could serve as a template for the design of PIN-modifying treatments to restore normal synaptic function.

项目概要导致自闭症风险的基因突变通常发生在谷氨酸突触表达的基因中。这些基因的蛋白质产物形成高度互连的蛋白质相互作用网络（PIN），并且代表有吸引力的治疗靶点，因为它们在整个生命周期中表达，并且可以急剧变化以小分子药物为目标。然而，该 PIN 的动态、网络规模行为在正常或人们对疾病状态知之甚少。在这里，我们应用了一种新颖的 PIN 映射技术，定量多重分析免疫共沉淀，探索与自闭症相关的 PIN 在谷氨酸上的输入输出关系突触响应生理输入。我们的目标系统是一个由 20 个成员组成的 PIN，由谷氨酸组成受体、支架和信号转导分子；编码所有目标蛋白的基因发生突变与自闭症有遗传联系。我们首先证明，在野生型动物中，我们的目标 PIN 发生了变化以刻板方式响应 KCl 或谷氨酸的急性刺激的共关联模式，使用培养的神经元或急性切片。然后我们对 PIN 系统的输入输出关系进行建模，并且证明 PIN 会产生特定的、可识别的特征来响应通过 mGluR 或 NMDA 受体。在生理性谷氨酸刺激的背景下，PIN 将两者结合起来输入产生协调的细胞反应——增强或去增强。基于这些和其他初步观察和已发表的数据，我们认为导致自闭症风险的突变会扰乱信息通过该 PIN 流动，从而实现类 LTP 增强和类 LTD 之间的平衡去电位被改变，最终导致机体水平上兴奋和抑制之间的不平衡。我们将通过对三种不同的 mGluR 或 NMDA 刺激的 PIN 反应进行建模来检验这一假设：特征明确的自闭症动物模型 - Fragile X 基因敲除、Shank3 基因敲除和 Ube3a 过度表达模型。我们将描述 mGluR 或 NMDA 刺激的输入输出关系，并使用主成分空间中的向量变换模型对它们的积分进行数学建模。我们将定义与自闭症相关的突变破坏输入输出关系的具体机制，或在生理刺激的情况下破坏信号整合。此外，我们还将治疗我们的两个动物模型（Shank3 和 Fragile X）使用先前已被证明可以拯救自闭症的药物 - 喜欢的行为。我们将模拟 PIN 对药物的反应，无论是否同时刺激定义与行为救援相关的 PIN 签名。总之，我们建议（1）定义正常信息流经由自闭症样基因的蛋白质产物组成的 PIN； (2) 定义如何自闭症小鼠模型中的信息流被破坏，目的是充分理解该系统设计靶向药物治疗；(3) 定义 PIN 如何响应纠正行为的药物，其中可以作为设计 PIN 修改治疗的模板，以恢复正常的突触功能。