Cell-intrinsic mechanisms of presynaptic assembly

突触前组装的细胞内在机制

• 批准号: 10884589
• 负责人: PERI T KURSHAN
• 金额: $ 10.16万
• 依托单位: ALBERT EINSTEIN COLLEGE OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-08-01 至 2023-12-14
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10884589
• 关键词: Actins; Address; Affect; Alleles; Axon; Binding; Biological; Biological Models; Biology; Brain; Caenorhabditis elegans; Cell Adhesion; Cell Adhesion Molecules; Cells; Cues; Cytoskeleton; Data; Defect; Dependence; Development; Disease; Disparate; Functional disorder; Genetic; Goals; Growth Cones; In Vitro; Integral Membrane Protein; Intellectual functioning disability; Kidney; Kinesin; Knowledge; Mammals; Mediating; Modeling; Molecular; Molecular Motors; Motor; Mutation; Nematoda; Nervous System; Neurodevelopmental Disorder; Optics; Phase; Physical condensation; Polymers; Positioning Attribute; Process; Protein Biosynthesis; Protein Isoforms; Proteins; Publishing; Recording of previous events; Research; Role; Scaffolding Protein; Schizophrenia; Signal Transduction; Site; Stereotyping; Synapses; Synaptic Cleft; System; Testing; Therapeutic Intervention; Translations; Vesicle; autism spectrum disorder; extracellular; genetic approach; imaging approach; in vivo; information processing; innovation; mutant; nephrin; neural circuit; neuronal circuitry; neuropsychiatric disorder; new therapeutic target; novel therapeutic intervention; podocyte; polymerization; preservation; presynaptic; programs; protein transport; recruit; scaffold; synaptic function; synaptogenesis; trafficking

PI: Kurshan, Peri T. PROJECT SUMMARY/ABSTRACT Synapses are the fundamental information processing units in the brain and their dysfunction leads to neurodevelopmental and neuropsychiatric disorders. Synapse development and organization is mediated in part by a class of transmembrane proteins called synaptic cell-adhesion molecules (sCAMs), and mutations in sCAM genes is highly associated with diseases such as autism, schizophrenia and intellectual disability, among others. The dominant model for synapse formation suggests that it is initiated by the trans-synaptic binding of sCAMs, however in vivo evidence for that model is lacking. Here we propose to uncover non-trans- synaptic cell-intrinsic molecular programs for presynaptic assembly that mediate the localization, trafficking and subcellular functions of sCAMs and other integral presynaptic proteins. Our preliminary evidence suggests that the intracellular domains of the presynaptic sCAMs neurexin and syg-2/nephrin are cell-autonomously required for presynaptic organization. Moreover, we find that the localization of neurexin to the presynaptic active zone is mediated by intracellular interactions with active zone scaffold proteins and kinesin motors. Finally, we have found that the dependence of sCAMs and other active zone proteins on transport by kinesins depends on the stage of axonal outgrowth. Based on these findings, we hypothesize that presynaptic assembly is mediated in large part by cell-intrinsic mechanisms. We propose to pursue three Specific Aims to characterize the mechanisms that govern (1) the intracellular recruitment of sCAMs, (2) the intracellular organization of proper synapse spacing by sCAM-mediated cytoskeletal rearrangement, and (3) the delivery and reallocation of sCAMs and other active zone proteins by kinesin- dependent and independent mechanisms at different stages of axonal outgrowth (Aim 3). To investigate these hypotheses, we leverage the genetic tractability and stereotyped nervous system of the nematode C. elegans, along with innovative imaging and genetic approaches. C. elegans has a long history of revealing fundamental synaptic biology and our previous published results and preliminary data position us well to take advantage of the power of this system. Collectively our proposed research will reveal how cell-intrinsic mechanisms govern the function of sCAMs in synapse formation. These studies have the potential to uncover the molecular mechanisms underlying neurodevelopmental disorders that result from defects in sCAM function, and thus provide targets for the development of specific therapeutic interventions.

PI：Kurshan，Peri T. 项目摘要/摘要 突触是大脑中的基本信息处理单元，其功能障碍导致 神经发育和神经精神疾病。突触发展和组织在 一类称为突触细胞粘附分子（骗局）的跨膜蛋白的一部分，以及突变 骗局基因与自闭症，精神分裂症和智力残疾等疾病高度相关， 等等。突触形成的主要模型表明它是由反式突触引发的 骗局的结合，但是缺乏该模型的体内证据。在这里，我们建议发现非交易 - 用于介导定位，贩运和 骗局和其他积分突触前蛋白的亚细胞功能。 我们的初步证据表明，突触前骗局神经毒素的细胞内结构域和 SYG-2/肾素是突触前组织所需的细胞自主。而且，我们发现 神经毒素在突触前活性区域的定位是通过与活性区的细胞内相互作用介导的 脚手架蛋白和动力素电动机。最后，我们发现骗局和其他活动的依赖性 驱动蛋白运输时的区域蛋白取决于轴突生长的阶段。基于这些发现，我们 假设突触前组装在很大程度上是通过细胞中性机制介导的。我们建议 追求三个特定的目的，以表征（1）细胞内募集的机制 骗局，（2）骗局介导的细胞骨架的适当突触间距的细胞内组织 重排，（3）驱动蛋白 - 在轴突产物的不同阶段的依赖和独立机制（AIM 3）。 为了研究这些假设，我们利用 线虫秀丽隐杆线虫，以及创新的成像和遗传方法。秀丽隐杆线虫有很长的 揭示基本突触生物学的历史以及我们先前发表的结果和初步数据的历史 定位我们充分利用该系统的力量。我们拟议的研究集体将揭示 细胞中的机制如何控制骗局在突触形成中的功能。这些研究具有 可能发现由神经发育障碍的分子机制的潜力 骗局功能的缺陷，因此为开发特定治疗干预措施提供了目标。