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: 10584530
• 负责人: Jason Aoto
• 金额: $ 18.44万
• 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/10584530
• 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; Image; Individual; Inhibitory Synapse; Knockout Mice; Knowledge; Ligands; Link; Maintenance; Mediating; Mental Health; Mental disorders; Molecular; Molecular Structure; Mus; Mutation; N-Methyl-D-Aspartate Receptors; Neurons; Peptide Signal Sequences; Phenotype; Play; Presynaptic Terminals; Property; Protein Isoforms; Proteins; Publishing; 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; superresolution imaging; superresolution microscopy; synaptic function; synaptogenesis; tool

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突触前的精确跨细胞排列 具有突触后特化的终末。神经递质释放和检测的部位不是 随机；相反，活动区释放机制是局部丰富的，并跨突触精确对齐 局部富含突触后支架和受体。最近，超分辨率显微镜技术的出现 揭示了许多对突触传递至关重要的蛋白质并不是均匀分布的，而是高度分布的 富含突触下域(SSD)。这些固态硬盘被排列以形成跨突触纳米柱，这些纳米柱 通常被认为是调节突触传递的功效。一个悬而未决的问题是：固态硬盘怎么样 调节、定位并排列成跨突触的纳米柱？跨突触细胞黏附分子 被提出控制突触的纳米级组织，因为它们跨越突触间隙，并且 能够通过细胞内和细胞外序列参与双向信号传递。强调 黏附分子的重要性，编码这些蛋白质的基因突变通常与 精神健康和药物使用障碍。虽然到目前为止研究的黏附分子聚集在或 在突触周围，突触前黏附蛋白的内源性操纵尚未揭示出 这些分子在控制跨突触SSD属性方面的指导作用。使用3D dSTORM 在超分辨成像中，我们发现了第一个神经尿蛋白NRXN3(NRXN3) 兴奋性突触的纳米级组织所必需的黏附分子。有条件的消融 在原代培养的海马神经元中，Neuresin-3显著降低突触密度、体积和 活动区和突触后SSD的跨突触排列。我们假设不同的NRXN3信号 序列控制着SSD的属性和纳米柱的比对，以及neuresin-3形成突触前SSD 与突触后密度固态硬盘直接对准。这项建议建立在我们初步和已公布的数据基础上 Neuresin-3是突触亚组织所必需的，对AMPAR介导的突触至关重要 变速箱。我们将利用3D dSTORM成像、分子结构/功能方法和鼠标 遗传学在两个特定的目标上测试我们的假设。首先，我们将直接研究neuresin-3在 兴奋性突触上的AMPA受体固态硬盘，并系统地进行结构/功能实验 确定纳米级所需的Neuresin-3的细胞内和细胞外信号序列 组织和固态硬盘协调。第二，我们将研究突触下定位和跨突触 内源性Neuresin-3的比对。综上所述，我们的发现将为Neuresin-3如何 信号调控突触下的结构以及neuresin-3功能障碍如何在病因中起作用 这是神经精神、神经发育和物质使用障碍的基础。