Molecular Analysis of BDNF-TrkB Regulation of Synapse Formation and Maintenance

BDNF-TrkB 突触形成和维持调节的分子分析

基本信息

批准号：
8420993
负责人：
Louis French Reichardt
金额：
$ 34.25万
依托单位：
UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
依托单位国家：
美国
项目类别：
财政年份：
2012
资助国家：
美国
起止时间：
2012-09-01 至 2017-04-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8420993
关键词：
Acute Addictive Behavior Adult Affect Alleles Appearance Behavior Binding Biochemical Brain Brain region Brain-Derived Neurotrophic Factor Cell Culture Techniques Cell Surface Proteins Cell surface Cells Cerebellum Detergents Development Disease Drug Delivery Systems Excision Excitatory Synapse Genes Health Heart Diseases Human Human Genetics Image In Vitro Inhibitory Synapse Kinetics Knowledge Ligands Maintenance Mediating Memory Mental Retardation Mental disorders Microscopy Modeling Molecular Molecular Analysis Moods Mutate Mutation Names Neurons Obesity Optics Performance Phosphorylation Post-Translational Protein Processing Protein Biosynthesis Proteins Proteomics Receptor Protein-Tyrosine Kinases Regulation Resistance Resolution Role Running Scaffolding Protein Schizophrenia Side Signal Transduction Site Staging Synapses Walking Work expectation gephyrin granule cell in vivo insight molecular assembly/self assembly motor control neuronal survival neurotrophic factor novel postsynaptic presynaptic protein degradation protein function protein protein interaction receptor reconstruction scaffold synaptogenesis

项目摘要

DESCRIPTION (provided by applicant): We will characterize mechanisms through which TrkB regulates inhibitory synapse formation and maintenance in the cerebellum with the expectation that the insights obtained will prove important for understanding the role of TrkB in many regions of the brain. Extending our prior demonstrations that TrkB controls inhibitory synapse formation throughout the cerebellum and has important pre- and postsynaptic cell- autonomous roles, we will use high resolution stochastic optical reconstruction microscopy (STORM) imaging to characterize the localizations of inhibitory synapse-associated cell surface and synaptic scaffold proteins and determine the effects of TrkB activation and inhibition on their presence at the synapse. Extending our recent observation that adult TrkB activity is required to maintain inhibitory synapses and that reactivation of TrkB signaling after earlier inhibition results in reappearance at the synapse of many synaptic proteins, we will examine the effects of adult TrkB inhibition and reactivation on the molecular composition of these synapses. Using cell culture we will examine in more detail the appearance and disappearance of proteins associated with the synapse following TrkB activation and inactivation. We shall determine whether TrkB functions in part through control of protein synthesis or turnover. We shall also examine the effects of TrkB activity on the kinetics of gephyrin stability, insertion and removal a synaptic sites in cell culture. Finally, we more critically examine our model that TrkB acts in par through control molecular assembly of the proteins that form the synaptic scaffold. We will determine the effects of TrkB activation and inactivation in vivo and in vitro on the distribution f gephyrin and other postsynaptic scaffold proteins in detergent soluble and resistant fractions, the interactions of these proteins with binding partners and on phosphorylation and other post-translational modifications. PUBLIC HEALTH RELEVANCE: This application will characterize mechanisms through which a neurotrophic factor implicated in neuronal survival named brain-derived neurotrophic factor (BDNF) signaling through a receptor tyrosine kinase named (TrkB) regulate synapse formation and maintenance in the cerebellum, a brain region that controls motor performance and coordination, such as walking and running. While the proposed studies focus on the cerebellum, the mechanistic insights are likely to be useful in understanding the function of this protein and its receptor in many regions of the brain, including those involved in memory, mood, and addictive behaviors. Human genetic studies have implicated BDNF in schizophrenia and other mental disorders. Rare human mutations in TrkB result in severe mental retardation, obesity, and cardiac disorders. The major aim of this proposal is to understand the mechanisms through which these genes control synapse formation and neuronal circuit function within the brain with the expectation that discoveries will identify novel targets for drugs to alleviate these devastatig disorders as well as increasing our knowledge of how the brain works in health and disease.

描述（由申请人提供）：我们将描述 TrkB 调节小脑中抑制性突触形成和维持的机制，期望所获得的见解对于理解 TrkB 在大脑许多区域中的作用非常重要。扩展我们之前的证明，即 TrkB 控制整个小脑的抑制性突触形成，并具有重要的突触前和突触后细胞自主作用，我们将使用高分辨率随机光学重建显微镜 (STORM) 成像来表征抑制性突触相关细胞表面的定位和突触支架蛋白并确定 TrkB 激活和抑制对其在突触中存在的影响。扩展我们最近的观察，即成人 TrkB 活性是维持抑制性突触所必需的，并且早期抑制后 TrkB 信号的重新激活会导致许多突触蛋白的突触重新出现，我们将检查成人 TrkB 抑制和重新激活对分子组成的影响这些突触。使用细胞培养，我们将更详细地检查 TrkB 激活和失活后与突触相关的蛋白质的出现和消失。我们将确定 TrkB 是否部分通过控制蛋白质合成或周转来发挥作用。我们还将检查 TrkB 活性对细胞培养物中 gephyrin 稳定性、插入和去除突触位点的动力学的影响。最后，我们更严格地检查了我们的模型，即 TrkB 通过控制形成突触支架的蛋白质的分子组装来发挥作用。我们将确定体内和体外 TrkB 激活和失活对 gephyrin 和其他突触后支架蛋白在洗涤剂可溶性和抗性组分中的分布、这些蛋白与结合伴侣的相互作用以及对磷酸化和其他翻译后修饰的影响。公共健康相关性：本申请将描述与神经元存活有关的神经营养因子（称为脑源性神经营养因子（BDNF））通过名为（TrkB）的受体酪氨酸激酶信号传导调节小脑（小脑是一个大脑区域）突触形成和维持的机制。控制运动表现和协调性，例如行走和跑步。虽然拟议的研究重点关注小脑，但机制见解可能有助于理解这种蛋白质及其受体在大脑许多区域的功能，包括那些与记忆、情绪和成瘾行为有关的区域。人类遗传学研究表明 BDNF 与精神分裂症和其他精神疾病有关。 TrkB 的罕见人类突变会导致严重的智力低下、肥胖和心脏病。该提案的主要目的是了解这些基因控制大脑内突触形成和神经元回路功能的机制，期望这些发现将确定药物的新靶标，以减轻这些破坏性疾病，并增加我们对如何治疗这些疾病的了解。大脑在健康和疾病中发挥作用。