STRUCTURE OF A GLUTAMATE RECEPTOR BINDING DOMAIN

谷氨酸受体结合域的结构

• 批准号: 7721328
• 负责人: ROBERT E OSWALD
• 金额: $ 2.69万
• 依托单位: CORNELL UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-08-01 至 2009-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7721328
• 关键词: Agonist; Amyotrophic Lateral Sclerosis; Binding; Binding Sites; Brain; Cations; Cell membrane; Collaborations; Computer Retrieval of Information on Scientific Projects Database; Condition; Crystallization; Disease; Drug Delivery Systems; Electron Spin Resonance Spectroscopy; Epilepsy; Extracellular Domain; Funding; GluR2 subunit AMPA receptor; Glutamate Receptor; Glutamates; Grant; Institution; Ion Channel; Ions; Ischemic Brain Injury; Laboratories; Length; Ligand Binding; Ligand Binding Domain; Ligands; Link; Lobe; Measurement; Measures; Motion; NMR Spectroscopy; Neuraxis; Neurons; Neurotransmitter Receptor; Pliability; Proteins; Range; Research; Research Personnel; Resolution; Resources; Source; Structure; Time; United States National Institutes of Health; Work; X-Ray Crystallography; extracellular; protein function; receptor binding

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Glutamate receptors are the major excitatory neurotransmitter receptors in vertebrate brain and are involved in a variety of normal and pathological neuronal functions. These proteins function by binding glutamate in an extracellular domain and opening an intrinsic ion channel that allows cations to flow in and out of the neuron. Drugs targeted to glutamate receptors may have considerable potential for treating such diverse disorders as epilepsy, amyotrophic lateral sclerosis, and ischemic brain damage. We are studying two important glutamate receptors (GluR2 and GluR3), using X-ray crystallography and NMR and ESR spectroscopy to understand the structure and dynamics and to compare the results with the function of the protein measured using single channel recording (measurement of ion conductance across the cell membrane). The structural work is done on the extracellular ligand-binding domains of the proteins (GluR2 S1S2 and GluR3 S1S2), which are a soluble constructs derived from the full-length proteins. The proteins have a bilobed structure with the binding site for glutamate and derivatives at the interface between the two lobes. For GluR2, previous work has suggested that the degree to which the lobes close upon binding of ligand may relate to the function of the protein. Our initial work with NMR spectroscopy and our recent crystal structures, suggest that the relationship between structure and function may be more complicated, involving protein flexibility. Obtaining additional structures, under conditions that reveal the range of possible motions, is essential for understanding the functional consequences of agonist binding. In collaboration with the Sondermann laboratory, we have obtained the structures of GluR2 S1S2 bound to several new ligands (1.5 to 1.7 angstrom resolution). The time requested in this cycle will be used to determine structures of GluR2 S1S2 with three new ligands under two crystallization conditions that we suspect will provide an indication of the range of possible motions of the protein. We also have crystals for GluR3 S1S2, the structure of which has not yet been determined. This protein is also available bound to at three different ligands. In addition the importance of understanding its crucial function in the central nervous system, the rationale for expanding these studies to the GluR3 subtype is that our functional studies of GluR3 have advanced considerably in recent years, and the hope of understanding in detail the link between structural changes in the binding domain to the conductance of ions through the cell membrane is very promising with this subtype. We have determined the conditions and have grown all of the crystals to be used in these studies. As noted above, the crystals that we have obtained from GluR2 diffract to high resolution (1.5 to 1.7 angstroms), and we anticipate similar results from the new crystals that we have obtained.

该副本是利用众多研究子项目之一 由NIH/NCRR资助的中心赠款提供的资源。子弹和 调查员（PI）可能已经从其他NIH来源获得了主要资金， 因此可以在其他清晰的条目中代表。列出的机构是 对于中心，这不一定是调查员的机构。 谷氨酸受体是脊椎动物大脑中的主要兴奋性神经递质受体，参与了多种正常和病理神经元功能。这些蛋白质通过在细胞外结构域中结合谷氨酸并打开固有离子通道，从而使阳离子流入和流出神经元。针对谷氨酸受体的药物可能具有治疗诸如癫痫，肌萎缩性侧面硬化症和缺血性脑损伤等多种疾病的潜力。我们使用X射线晶体学以及NMR和ESR光谱研究了两个重要的谷氨酸受体（GLUR2和GLUR3），以了解结构和动力学，并将结果与​​使用单个通道记录测量的蛋白质的功能进行比较（在细胞膜中测量离子电导率的测量）。结构工作是在蛋白质的细胞外配体结合结构域（GlUR2 S1S2和GlUR3 S1S2）上完成的，该结构是从全长蛋白中得出的可溶构建体。蛋白质在两个裂片之间的界面处具有谷氨酸和衍生物的结合位点的双重结构。对于GlUR2，以前的工作表明，配体结合后裂片接近的程度可能与蛋白质的功能有关。我们与NMR光谱法和最近的晶体结构的最初工作表明，结构和功能之间的关系可能更复杂，涉及蛋白质柔韧性。在揭示可能的运动范围的条件下获得其他结构对于理解激动剂结合的功能后果至关重要。 与Sondermann实验室合作，我们获得了与几种新配体（1.5至1.7 Angstrom分辨率）结合的Glur2 S1S2的结构。在此周期中要求的时间将用于确定在两个结晶条件下使用三个新配体的Glur2 S1S2的结构，我们怀疑这将表明该蛋白质的可能运动范围。我们也有用于GlUR3 S1S2的晶体，尚未确定其结构。该蛋白也可在三种不同的配体处结合。除了了解其在中枢神经系统中其关键功能的重要性外，将这些研究扩展到GLUR3亚型的理由是，近年来，我们对GlUR3的功能研究已经相当大得多，并且详细了解结构变化之间的结构变化与通过细胞膜的结构变化之间的结构变化与该子类型的链接非常有希望。 我们已经确定了这些条件，并种植了这些研究中使用的所有晶体。如上所述，我们从GlUR2衍射到高分辨率（1.5至1.7埃斯特罗姆）获得的晶体，我们预计我们获得的新晶体会产生相似的结果。