MOLECULAR MECHANISMS OF GLUTAMATE RECEPTOR CHANNELS

谷氨酸受体通道的分子机制

• 批准号: 2622983
• 负责人: Anthony L Auerbach
• 金额: $ 17.82万
• 依托单位: STATE UNIVERSITY OF NEW YORK AT BUFFALO
• 依托单位国家: 美国
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-04-01 至 2003-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2622983
• 关键词: Xenopus; Xenopus oocyte; animal genetic material tag; calcium ion; chemical binding; genetic markers; glutamate receptor; hippocampus; laboratory rat; magnesium ion; molecular site; neurons; neuropharmacology; neurotransmitter antagonist; protein structure function; receptor binding; recombinant proteins; site directed mutagenesis; tissue /cell culture

The long term goal of this research is to understand the mechanisms by which synapses in the brain are changed by activity and environmental stimuli. We focus on a specific type of synaptic receptor - the NMDA class of glutamate receptor - that plays an important role in long-term changes in synaptic function, the regulation of cell-death, and the generation of patterned activity in neuronal networks. These processes require that the NMDA receptors allow the appropriate amount of calcium ion to pass through its pore and enter the neuron, and be blocked by extracellular magnesium ion over an appropriate range of membrane potentials and concentrations. Thus, in order to understand the molecular bases of synaptic plasticity, we must understand the mechanisms that determine the divalent cation permeability and block of NMDA receptors. We will use recombinant DNA technology to make point mutations in the receptor protein, and then study the altered functions of mutant receptors (expressed in oocytes) using single-channel patch clamp methods. We will investigate how the pore residues, and the subunit composition of the receptor, determine the affinity for calcium and magnesium, if the channel conductance is regulated by electrostatic mechanisms, and the mechanisms by which subconductance levels are generated. We will also investigate the subunit composition (type and copy number) of receptors by studying the patterns of subconductance states that are apparent in receptors composed of different mixtures of wild type and mutant subunits. An understanding of the molecular mechanisms of operation of NMDA receptors channels will provide insight into the basis of developmental, degenerative and other diseases of the nervous system.

这项研究的长期目标是通过以下方式了解其机制： 大脑中的哪些突触会因活动和环境而改变 刺激。 我们专注于一种特定类型的突触受体 - NMDA 谷氨酸受体一类 - 在长期作用中发挥着重要作用 突触功能的变化、细胞死亡的调节以及 神经元网络中模式活动的产生。 这些过程 需要NMDA受体允许适量的钙 离子通过其孔进入神经元，并被 细胞外镁离子在适当的膜范围内 潜力和浓度。 因此，为了理解 突触可塑性的分子基础，我们必须了解 决定二价阳离子渗透性和阻滞的机制 NMDA 受体。 我们将利用重组DNA技术来证明这一点 受体蛋白突变，然后研究改变的功能 使用单通道贴片突变受体（在卵母细胞中表达） 夹紧方法。 我们将研究孔隙残留物如何，以及 受体的亚基组成，确定对钙的亲和力 和镁，如果通道电导受静电调节 机制，以及亚电导水平的机制 生成的。 我们还将研究亚基组成（类型和 通过研究亚电导模式来确定受体的拷贝数 在由不同混合物组成的受体中明显的状态 野生型和突变型亚基。 对分子的理解 NMDA 受体通道的运作机制将提供见解 成为发育、退行性疾病和其他疾病的基础 神经系统。