Control of subsynaptic domain organization and nanocolumn alignment by neurexin-3

neurexin-3 控制突触亚域组织和纳米柱排列

• 批准号: 10429177
• 负责人: Jason Aoto
• 金额: $ 22.33万
• 依托单位: UNIVERSITY OF COLORADO DENVER
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-03-04 至 2024-02-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10429177
• 关键词: 3-Dimensional; AMPA Receptors; Ablation; Address; Adhesions; Alternative Splicing; Architecture; Biology; Brain; Brain region; Cell Adhesion Molecules; Characteristics; Communication; Confocal Microscopy; DLG4 gene; Data; Data Analyses; Data Collection; Detection; Ensure; Epitopes; Essential Genes; Etiology; Excitatory Synapse; Exhibits; Exons; Functional disorder; Genes; Genetic; Genomics; Hippocampus (Brain); Image; Individual; Inhibitory Synapse; Instruction; Knockout Mice; Knowledge; Lead; Ligands; Link; Maintenance; Mediating; Mental Health; Mental disorders; Microscopy; Molecular; Molecular Structure; Mus; Mutation; N-Methyl-D-Aspartate Receptors; Neurons; Peptide Signal Sequences; Phenotype; Play; Presynaptic Terminals; Property; Protein Isoforms; Proteins; Publishing; Resolution; Role; Schizophrenia; Sequence Homology; Signal Transduction; Site; Structure; Substance Use Disorder; Synapses; Synaptic Cleft; Synaptic Transmission; Testing; Work; autism spectrum disorder; cell type; conditional knockout; density; experimental study; extracellular; insight; interest; mouse genetics; nano; nanocolumn; nanoscale; neuropsychiatry; neurotransmitter release; postsynaptic; postsynaptic density protein; presynaptic; promoter; receptor; scaffold; stress disorder; synaptic function; synaptogenesis; tool; trafficking

Project Summary/Abstract Efficient synaptic communication between neurons requires precise transcellular alignment of the presynaptic terminal with the postsynaptic specialization. The sites of neurotransmitter release and detection are not random; instead the active zone release machinery is locally enriched and precisely aligned transsynaptically with locally enriched postsynaptic scaffolds and receptors. Recently, super-resolution microscopy approaches have revealed that many proteins critical for synaptic transmission are not uniformly distributed but highly enriched in subsynaptic domains (SSDs). These SSDs are aligned to form transsynaptic nanocolumns that are commonly thought to regulate the efficacy of synaptic transmission. An outstanding question is: how are SSDs regulated, localized and aligned into transsynaptic nanocolumns? Transsynaptic cell adhesion molecules have been proposed to control the nanoscale organization of synapses because they span the synaptic cleft and are capable of participating in bidirectional signaling via intracellular and extracellular sequences. Underscoring the importance of adhesion molecules, mutations in genes that encode these proteins are commonly linked to mental health and substance use disorders. While adhesion molecules studied thus far cluster in SSDs in or around the synapse, the endogenous manipulation of presynaptic adhesion proteins has yet to reveal an instructive role for these molecules in controlling transsynaptic SSD properties. Using 3D dSTORM superresolution imaging, we have identified neurexin-3 (Nrxn3) as the first neurexin and first presynaptic adhesion molecule necessary for the nanoscale organization of excitatory synapses. Conditional ablation of neurexin-3 in primary hippocampal cultures significantly reduced the synaptic density, volume and transsynaptic alignment of active zone and postsynaptic SSDs. We hypothesize that distinct Nrxn3 signaling sequences govern SSD properties and nanocolumn alignment and that neurexin-3 forms presynaptic SSDs directly aligned with postsynaptic density SSDs. This proposal builds on our preliminary and published data that neurexin-3 is necessary for subsynaptic organization and critical for AMPAR-mediated synaptic transmission. We will utilize 3D dSTORM imaging, molecular structure/function approaches and mouse genetics to test our hypothesis in two specific aims. First, we will directly examine the role of neurexin-3 on AMPA-receptor SSDs at excitatory synapses and systematically perform structure/function experiments to determine the intracellular and extracellular signaling sequences of neurexin-3 required for nanoscale organization and SSD alignment. Second, we will investigate the subsynaptic localization and transsynaptic alignment of endogenous neurexin-3. Together, our findings will provide critical insight into how neurexin-3 signaling governs subsynaptic architecture and how dysfunction of neurexin-3 can contribute to the etiologies that underlie neuropsychiatric, neurodevelopmental and substance use disorders.

项目摘要/摘要 神经元之间有效的突触通信需要精确的突触前的跨对准 终端具有突触后专业化。神经递质释放和检测的位置不是 随机的;相反，活动区释放机械在本地富集并精确地对齐。 具有局部富集的突触后支架和受体。最近，超分辨率显微镜方法 已经揭示了许多至关重要的突触传播的蛋白质不是均匀分布的，但高度分布 富含突触域（SSD）。这些SSD是一致的 通常认为调节突触传播的功效。一个杰出的问题是：SSD如何 受调节，本地化并对齐转染色纳米colloclumns？跨突触细胞粘附分子具有 被提议控制纳米级突触组织，因为它们跨越了突触裂。 能够通过细胞内和细胞外序列参与双向信号。强调 粘附分子的重要性，编码这些蛋白质的基因中的突变通常与 心理健康和药物使用障碍。迄今为止在SSD中研究的粘附分子在或 在突触周围，突触前粘附蛋白的内源性操纵尚未揭示 这些分子在控制透射性SSD特性中的启发性作用。使用3D DSTORM 超分辨率成像，我们已经确定Neurexin-3（NRXN3）为第一个神经毒素和第一个突触前 纳米级兴奋性突触组织所需的粘附分子。条件消融 原发性海马培养物中的Neurexin-3显着降低了突触密度，体积和 活性区和突触后SSD的跨突触比对。我们假设不同的NRXN3信号传导 序列控制SSD特性和纳米颜色对齐，而Neurexin-3形成突触前SSD 直接与突触后密度SSD对齐。该建议建立在我们的初步和已发布的数据基础上 Neurexin-3对于次触及组织是必不可少的，对于AMPAR介导的突触至关重要 传播。我们将利用3D DSTORM成像，分子结构/功能方法和小鼠 遗传学以两个具体目标检验我们的假设。首先，我们将直接检查Neurexin-3在 兴奋性突触处的AMPA受体SSD，并系统地执行结构/功能实验 确定纳米级所需的神经3的细胞内和细胞外信号传导序列 组织和SSD对齐。其次，我们将研究突触的次触及定位和跨突触 内源性神经3的比对。一起，我们的发现将提供有关神经素3的批判性见解 信号传导控制突触次突的结构以及神经3的功能障碍如何有助于病因 这是神经精神病，神经发育和物质使用障碍的基础。