Defining the architecture and activation mechanisms of SynGAP

定义SynGAP的架构和激活机制

• 批准号: 10646985
• 负责人: Eric Steven Underbakke
• 金额: $ 17.38万
• 依托单位: IOWA STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-02-01 至 2025-01-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10646985
• 关键词: Affinity; Allosteric Regulation; Architecture; Biological Assay; Biological Markers; Brain; Brain Diseases; C-terminal; C2 Domain; Characteristics; Chemicals; Communication; Complex; Computer Models; Coupled; Cytoskeleton; Data; Deuterium; Development; Disease; Docking; Excitatory Synapse; Exhibits; Fluorescent Probes; Foundations; Functional disorder; Future; GTPase-Activating Proteins; Glutamate Receptor; Goals; Guanosine Triphosphate Phosphohydrolases; Holoenzymes; Human; Hybrids; Hydrogen; Intellectual functioning disability; Knowledge; Learning; Long-Term Potentiation; Maps; Mass Spectrum Analysis; Membrane; Membrane Proteins; Memory; Mental disorders; Modeling; Molecular; Molecular Conformation; Molecular Neurobiology; Monomeric GTP-Binding Proteins; Movement; Multiprotein Complexes; Mutagenesis; Mutation; N-terminal; Neurons; Outcome; PH Domain; Pathway interactions; Phosphorylation; Phosphorylation Site; Play; Protein Dynamics; Protein Footprinting; Proteins; Proteomics; Public Health; Research; Roentgen Rays; Role; Schizophrenia; Shapes; Signal Transduction; Signaling Protein; Specificity; Spectrum Analysis; Structural Models; Structure; Surface Plasmon Resonance; Synapses; Synaptic plasticity; Tail; Tertiary Protein Structure; Therapeutic; activated Protein C; autism spectrum disorder; biophysical techniques; biophysical tools; crosslink; density; design; frontier; link protein; postsynaptic; protein function; protein structure; ras GTPase-Activating Proteins; restraint; scaffold; structural biology; structural determinants; tool

Project Summary Excitatory synapses exhibit characteristic proteinaceous microcompartments at the membrane known as the post-synaptic density (PSD). The PSD is richly organized into multi-protein complexes composed of glutamate receptors, scaffolds, cytoskeleton, and signaling effectors. The dynamic reorganizations of the higher-order architecture and composition of PSD signaling complexes underlies synaptic plasticity, learning, and memory. Dissecting the interactions and allosteric communication mechanisms of the PSD is a prerequisite for understanding the molecular underpinnings of synaptic plasticity. Synaptic signaling complexes are large and highly dynamic, problematic targets for mainstay structural biology approaches. The overarching goals of this project are to surmount the challenges of structural characterization of PSD signaling complexes by applying a battery of protein footprinting, spectroscopies, chemical tools, and proteomics approaches to probe protein structure in biologically relevant milieu. This project focuses on the architecture, activation mechanisms, and scaffolding roles of SynGAP, an abundant PSD GTPase-activating protein. SynGAP is critical to brain development, long-term potentiation, and spatial learning. Importantly, SynGAP mutations in humans are associated with autism spectrum disorders, schizophrenia, and intellectual disability. Despite its ubiquity and central signaling role, the architecture and signaling mechanisms of SynGAP remain largely unknown. Defining the molecular mechanisms of SynGAP signaling is critical for understanding the basis of brain disorders caused by SynGAP dysfunction. Hybrid structural biology approaches will be integrated to build a structural model of the multi-domain holoenzyme. These approaches are uniquely amenable to characterizing dynamic protein interfaces and conformational changes in solution. Phosphorylation-induced conformational changes will be defined to determine activation mechanisms. SynGAP apparently regulates opposing pathways dictating synaptic strength via dual specificity toward both Ras and Rap. Specificity switching mechanisms will be revealed by mapping structural determinants of Ras and Rap interactions. By dissecting the structural basis for SynGAP function the proposed research will be a vital contribution to the ongoing movement to characterize the molecular architecture of the PSD. Resolving SynGAP signaling complex structure and mechanisms will clarify the basis of SynGAP-linked neuronal disorders and spur the development of future therapeutics.

项目摘要 兴奋性突触在膜上表现出特征性的蛋白质微区室， 突触后密度（PSD）。PSD丰富地组织成多蛋白质复合物， 谷氨酸受体、支架、细胞骨架和信号效应物。企业的动态重组 PSD信号复合物的高级结构和组成是突触可塑性的基础， 学习和记忆。剖析PSD的相互作用和变构通讯机制 是理解突触可塑性的分子基础的先决条件。突触信号 复合物是大的和高度动态的，对于主流结构生物学方法来说是有问题的目标。 该项目的总体目标是克服结构表征的挑战， PSD信号复合物通过应用一系列蛋白质足迹，光谱学，化学工具， 和蛋白质组学方法来探测生物相关环境中的蛋白质结构。这个项目 着重于SynGAP的结构、激活机制和支架作用，SynGAP是一种丰富的PSD GTP酶激活蛋白。SynGAP对大脑发育、长时程增强和空间功能至关重要。 学习重要的是，人类的SynGAP突变与自闭症谱系障碍有关， 精神分裂症和智力残疾。尽管其无处不在和中央信号作用， SynGAP的信号传导机制仍不清楚。定义的分子机制 SynGAP信号传导对于理解SynGAP引起的大脑疾病的基础至关重要 功能障碍混合结构生物学方法将被整合，以建立一个结构模型， 多结构域全酶这些方法是唯一适合于表征动态蛋白质 界面和溶液中的构象变化。磷酸化诱导的构象变化 将被定义以确定激活机制。SynGAP明显调节相反的途径 通过对Ras和Rap的双重特异性决定突触强度。特异性转换 机制将通过绘制Ras和Rap相互作用的结构决定因素来揭示。通过 解剖SynGAP功能的结构基础，拟议的研究将是一个至关重要的贡献， 正在进行的运动，以表征PSD的分子结构。解决SynGAP 信号复合物的结构和机制将阐明SynGAP相关神经元疾病的基础 并促进未来治疗学的发展。