Role of matrix metalloproteinases in synaptic plasticity

基质金属蛋白酶在突触可塑性中的作用

基本信息

批准号：
7624572
负责人：
GEORGE W. HUNTLEY
金额：
$ 36.02万
依托单位：
ICAHN SCHOOL OF MEDICINE AT MOUNT SINAI
依托单位国家：
美国
项目类别：
财政年份：
2007
资助国家：
美国
起止时间：
2007-07-04 至 2012-05-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7624572
关键词：
Actins Active Sites Acute Address Adhesions Adult Area Behavioral Biochemical Brain Cell surface Chemosensitization Cytoskeleton Data Dendritic Spines Electric Stimulation Employee Strikes Endopeptidases Extracellular Matrix Extracellular Matrix Proteins Family Functional disorder Gelatinase B Goals Hippocampus (Brain)Image Injury Integrins Learning Life Link Matrix Metalloproteinases Mediating Memory Methods Molecular Morphology Neurons Peptide Hydrolases Physiology Plastics Process Proteins Proteolysis Protocols documentation Publishing Rattus Reagent Regulation Role Signal Transduction Slice Synapses Synaptic plasticity Testing Time Tissues Urethane Vertebral column Whole-Cell Recordings base cell motility dentate gyrus extracellular in vivo insight long term memory loss of function novel receptor research study response skills two-photon

项目摘要

DESCRIPTION (provided by applicant): The long-term goal is to understand mechanisms of synaptic functional and structural plasticity in brain. This is important because such plasticity represents cellular mechanisms enabling memory. Matrix metalloproteinases (MMPs) are a family of extracellular peptidases whose targets include extracellular matrix (ECM). Canonically, they function to remodel the pericellular microenvironment. Here, we address the novel hypothesis that in brain, regulated MMP-mediated extracellular proteolysis coordinates synaptic signaling and remodeling during synaptic and behavioral plasticity. In Aim 1, regulation and activation of MMP-9 during synaptic plasticity is studied in vivo using electrical stimulation protocols and field recordings to elicit different forms of synaptic plasticity in area CA1. Pharmacological methods are used to establish the timecourse over which levels of MMP-9 protein and proteolytic activity are regulated; gain- and loss-of- function approaches are used to establish functional roles of MMP-9 in synaptic physiology and plasticity; novel reagents and methods including the use of fluorescently tagged MMP active-site directed probes are used to determine if MMP-9 is activated globally during plasticity or locally in relationship to plastic synapses. In Aim 2, effects of active MMP-9 on neuronal form and function are tested. Gain- and loss-of- function approaches combined with two-photon time-lapse imaging of living dendritic spines and whole-cell recording will be applied to acute hippocampal slices to: a) characterize changes in spine motility, morphology and actin dynamics in relationship to MMP-mediated potentiation; and b) determine the relationship between MMP-9 mediated structural plasticity and integrin activation. In Aim 3, a hippocampal- dependent learning and memory task will be used in conjunction with subsequent biochemical, anatomical and loss-of-function approaches in order to determine: a) the timecourse and localization of learning-induced MMP-9 activation; and b) the effects of neutralizing proteolytic activity on strength of memory. The experiments will reveal new, fundamental roles for MMPs in normal brain function, and provide new insight into molecular mechanisms that regulate synaptic and behavioral plasticity.

描述（由申请人提供）：长期目标是了解大脑突触功能和结构可塑性的机制。这很重要，因为这种可塑性代表了能够记忆的细胞机制。基质金属蛋白酶（MMP）是一个细胞外肽酶家族，其靶标包括细胞外基质（ECM）。在规范上，它们起作用可重塑周围的微环境。在这里，我们解决了一个新的假设，即在大脑中，MMP介导的细胞外蛋白水解坐标在突触和行为可塑性过程中突触信号传导和重塑。在AIM 1中，使用电刺激方案和现场记录在体内研究了MMP-9在突触可塑性过程中的调节和激活，以在CA1区域引起不同形式的突触可塑性。药理学方法用于确定MMP-9蛋白质和蛋白水解活性的水平；功能丧失方法用于建立MMP-9在突触生理和可塑性中的功能作用。新型试剂和方法，包括使用荧光标记的MMP有效探针的使用，用于确定在可塑性期间或与塑料突触的关系中，MMP-9是否在全球范围内激活。在AIM 2中，测试了主动MMP-9对神经元形式和功能的影响。生命树突状刺和全细胞记录的两光子的延时成像的增益和功能丧失方法将应用于急性海马切片至： b）确定MMP-9介导的结构可塑性与整合素激活之间的关系。在AIM 3中，将与随后的生化，解剖学和功能丧失方法一起使用海马依赖的学习和记忆任务，以确定：a）学习诱导的MMP-9激活的时间和定位； b）中和蛋白水解活性对记忆力强度的影响。该实验将揭示MMP在正常脑功能中的新的，基本的作用，并提供对调节突触和行为可塑性的分子机制的新见解。