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：
8078178
负责人：
GEORGE W. HUNTLEY
金额：
$ 35.66万
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 2013-05-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8078178
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中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实现记忆的细胞机制。基质金属蛋白酶 (MMP) 是细胞外肽酶家族，其靶标包括细胞外基质 (ECM)。通常，它们的作用是重塑细胞周微环境。在这里，我们提出了一个新的假设，即在大脑中，受调节的 MMP 介导的细胞外蛋白水解在突触和行为可塑性过程中协调突触信号传导和重塑。在目标 1 中，使用电刺激方案和现场记录在体内研究突触可塑性期间 MMP-9 的调节和激活，以引发 CA1 区不同形式的突触可塑性。使用药理学方法确定 MMP-9 蛋白水平和蛋白水解活性受到调节的时间过程；使用功能获得和丧失方法来确定 MMP-9 在突触生理学和可塑性中的功能作用；新的试剂和方法，包括使用荧光标记的 MMP 活性位点定向探针，用于确定 MMP-9 在可塑性过程中是否被全局激活，或与可塑性突触相关的局部激活。在目标 2 中，测试了活性 MMP-9 对神经元形态和功能的影响。功能获得和丧失的方法与活体树突棘的双光子延时成像和全细胞记录相结合，将应用于急性海马切片，以：a）表征脊柱运动、形态和肌动蛋白动力学变化的关系MMP 介导的增强作用； b) 确定 MMP-9 介导的结构可塑性和整合素激活之间的关系。在目标 3 中，海马依赖性学习和记忆任务将与随后的生化、解剖和功能丧失方法结合使用，以确定： a) 学习诱导的 MMP-9 激活的时间过程和定位； b) 中和蛋白水解活性对记忆强度的影响。这些实验将揭示 MMP 在正常大脑功能中的新的基本作用，并为调节突触和行为可塑性的分子机制提供新的见解。