Generating functional diversity from molecular homogeneity at glutamatergic synapses

从谷氨酸突触的分子同质性产生功能多样性

• 批准号: 10583404
• 负责人: DION KAI DICKMAN
• 金额: $ 39.46万
• 依托单位: UNIVERSITY OF SOUTHERN CALIFORNIA
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-12-01 至 2027-11-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10583404
• 关键词: Action Potentials; Address; Alzheimer' s Disease; Automobile Driving; Biological Models; Botulinum Toxins; Calcium; Calibration; Chemosensitization; Clustered Regularly Interspaced Short Palindromic Repeats; Communication; Coupling; Data; Defect; Development; Disease; Drosophila genus; Electrophysiology (science); Epilepsy; Etiology; Failure; Functional disorder; Genes; Genetic; Glutamates; Goals; Health; Heterogeneity; Homologous Gene; Individual; Knowledge; Mammals; Mental disorders; Microscopy; Modeling; Molecular; Molecular Machines; Motor; Motor Neurons; Muscle; Muscle Contraction; Mutagenesis; Nanostructures; Nervous System; Neurodegenerative Disorders; Neurodevelopmental Disorder; Neuromuscular Junction; Neurons; Neurophysiology - biologic function; Orthologous Gene; Phase; Positioning Attribute; Process; Property; Protein Isoforms; RNA Splicing; Reagent; Reporter; Role; Schizophrenia; Site; Structure; Synapses; Synaptic plasticity; System; Toxic effect; Vesicle; autism spectrum disorder; botulinum toxin type C; experience; experimental study; fly; imaging approach; innovation; insight; nanoscale; nervous system disorder; neural; neural circuit; neuropsychiatric disorder; neurotransmission; neurotransmitter release; postsynaptic; presynaptic; prevent; ratiometric; scaffold; superresolution imaging; synaptic function; therapeutically effective; transmission process; ultra high resolution

PROJECT SUMMARY Synapses are fundamental units of communication in the nervous system, where immense diversity in structure and function serve to tune and calibrate information transfer. Defects in the ability of synapses to properly diversify contribute to the etiology of a variety of neurodevelopmental, psychiatric, and neurodegenerative diseases. One means of generating diversity in synaptic function is through molecular heterogeneity, where combinations of distinct genes are expressed at individual synapses to enable specific functional properties. However, it has become increasingly clear, though difficult to resolve, that remarkable synaptic diversity can be achieved from a limited set of molecular machinery. In principle, the Drosophila neuromuscular junction (NMJ) is a uniquely powerful model to address how synaptic diversity is generated given the sophisticated genetic, electrophysiological, and imaging approaches. In this system, two distinct motor neurons converge to co-innervate individual muscle targets, where transmission from a strong and weak input together drive muscle contraction in the motor circuit. However, an inability to selectively isolate transmission from either input has been a major limitation towards understanding synaptic diversity in this system. Here, we propose to use expression of a unique Botulinum NeuroToxin (BoNT) to selectively silence transmission at strong or weak synaptic inputs. Preliminary data suggests that while each neuron is largely composed of the same molecular machinery at active zones, one core component, previously thought to function universally at all active zones, actually subserves dramatically different roles at strong vs weak synapses. We will use BoNT silencing, super resolution imaging, and the latest calcium reporters targeted to release sites to illuminate differences in active zone nanostructure and function between strong and weak synapses. We will also leverage new innovations in CRISPR mutagenesis to dissect the specialized functions of eight core active zone components at strong vs weak synapses. Finally, we will interrogate how these core active zone components are uniquely targeted for modulation and remodeling at strong vs weak synapses in the context of homeostatic synaptic plasticity. Together, these approaches will unlock fundamental insights into how glutamatergic synaptic diversity is established and adaptively modified through plasticity. Ultimately, this understanding will illuminate key mechanisms through which heterogeneous functional properties at glutamatergic release sites are enabled by a limited molecular toolkit.

项目总结 突触是神经系统中交流的基本单位，在那里 结构和功能上的多样性有助于调整和校准信息传输。产品中的缺陷 突触适当多样化的能力有助于多种疾病的病因学 神经发育、精神和神经退行性疾病。一种生成 突触功能的多样性是通过分子的异质性实现的，其中不同的组合 基因在单个突触上表达，以实现特定的功能特性。然而，它 已经变得越来越清楚，尽管很难解决，但显著的突触多样性可以 是通过一套有限的分子机器实现的。原则上，果蝇的神经肌肉 连接(NMJ)是一个独特的强大的模型，以解决如何产生突触多样性给定 先进的遗传、电生理和成像方法。在这个系统中，有两个 不同的运动神经元会聚在一起共同神经支配单个肌肉靶点，在那里传递 从强弱输入共同驱动肌肉收缩的马达回路。然而，一个 无法有选择地将传播与任何一种输入隔离，一直是对 了解这个系统中的突触多样性。在这里，我们建议使用唯一的 肉毒神经毒素选择性沉默强突触或弱突触的传递 投入。初步数据表明，虽然每个神经元主要由相同的 活动区的分子结构，一个核心组件，以前被认为起作用 在所有活动区普遍存在，实际上在强势和弱势中扮演着截然不同的角色 突触。我们将使用BONT消音、超分辨率成像和最新的钙记者 有针对性地释放部位，以阐明活动区纳米结构和功能的差异 强突触和弱突触之间。我们还将利用CRISPR的新创新 用诱变技术剖析八个核心活性区域成分的特殊功能 VS弱突触。最后，我们将询问这些核心活动区组件是如何 唯一针对强突触与弱突触的调制和重塑 动态平衡突触可塑性。结合起来，这些方法将开启对以下问题的基本见解 谷氨酸能突触多样性是如何通过可塑性建立和适应性修改的。 最终，这种理解将阐明异构性的关键机制 谷氨酸能释放部位的功能特性是由有限的分子工具箱实现的。