Molecular determinants of synaptic diversity at the nanoscale

纳米尺度突触多样性的分子决定因素

• 批准号: 10543065
• 负责人: Dariya Bakshinskaya
• 金额: $ 4.16万
• 依托单位: UNIVERSITY OF CALIFORNIA BERKELEY
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-12-10 至 2023-11-09
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10543065
• 关键词: Action Potentials; Acute; Address; Behavior; Binding; Cells; Chronic; Communication; Data; Development; Diglycerides; Disease; Drosophila melanogaster; Electrophysiology (science); Elements; Evoked Potentials; Excitatory Synapse; Frequencies; Functional Imaging; Functional disorder; Genetic; Glutamates; Goals; Health; Heterogeneity; Human; Individual; Knowledge; Learning; Measures; Membrane; Memory; Methods; Modeling; Molecular; Morphology; Nanostructures; Nerve Degeneration; Nervous System; Nervous System Physiology; Neurodegenerative Disorders; Neurodevelopmental Disorder; Neuromuscular Junction; Neurons; Neurosciences; Optics; Parkinson Disease; Physiology; Probability; Process; Property; Proteins; Research; Resolution; Role; Schizophrenia; Sensory; Shapes; Site; Structural Protein; Synapses; Synaptic Transmission; Synaptic Vesicles; System; Testing; Therapeutic; Time; Training; Work; analog; autism spectrum disorder; experimental study; fly; frontier; imaging modality; improved; in vivo; information processing; inhibitor; insight; interest; knock-down; nano; nanometer; nanoscale; nervous system disorder; neural; neural circuit; novel; overexpression; pharmacologic; presynaptic; structural imaging; tool; transmission process; ultra high resolution

-Abstract - Synapses are the fundamental units of communication in the nervous system and reliable synaptic transmission is central to key nervous system processes such as learning, memory, and sensory adaptation. Moreover, due to dysfunctions at the synapse, many neurological diseases may develop. While electrophysiological studies of synaptic transmission have been around for a long time, only the recent development of optical quantal analysis (OQA) tools has made possible to correlate morphological and structural elements to transmission properties of individual synapses. Studies using OQA have revealed a much larger diversity in synaptic transmission, even among neighboring synapses, than was previously thought. The advent of higher-resolution OQA, such as the one developed in our lab called “QuaSOR”, and super-resolution structural imaging methods opens up an exciting frontier of being able to investigate how neural activity shapes (and is shaped by) synaptic diversity, what are the molecular determinants and mechanisms the set this diversity, and how do these molecular determinants shape synaptic diversity. By using OQA, we've shown that synaptic diversity, as measured by difference in synaptic strength (i.e., probability of action potential evoked transmission; Pr ) is extremely heterogeneous (Pr: 0.01–0.5) within a single neuron synapsing onto a single target cell. This high degree of heterogeneity leads us to the central hypothesis of my thesis which is that synaptic strength is set by a very precise, local distribution of key proteins. To test this hypothesis I will use the model glutamatergic synapse–Drosophila melanogaster larval neuromuscular junction (NMJ)– where I will investigate hundreds of synapses in parallel, in vivo, and address synaptic heterogeneity from both functional and structural perspectives at single synapse resolution (50-100nm). For my thesis I am being trained in synaptic physiology, fly genetics, and advanced super-resolution functional/structural imaging and analysis. In Aim 1 of my thesis, I will establish the degree of functional synaptic heterogeneity in vivo single synapses using QuaSOR. Specifically, I have completed the preliminary experiments investigating the extent of basal synaptic heterogeneity and addressing the relationship between basal strength of synapses (basal Pr) and synaptic adaptation to higher frequencies. Through super-resolution structural imaging experiments proposed for Aim 2, I will investigate some of the key proteins at the synapse and determine whether it's the local quantities, the relative abundance between them (ratios), and/or the nanolocalization within the synapse that shape synaptic diversity. Finally, for Aim 3, through chronic and acute manipulations, I will determine the role of Unc-13a in shaping this diversity. Through the combination of super resolution structural and functional imaging, this proposed work will yield much needed insight into the molecular determinants that may shape synaptic diversity.

-抽象的 - 突触是神经系统中交流的基本单位和可靠的突触 传播是关键神经系统过程的核心，例如学习，记忆和感觉适应。 此外，由于突触的功能障碍，许多神经系统疾病可能出现。尽管 突触传播的电生理研究已经存在很长时间了，只有最近 光学量化分析（OQA）工具的开发已成为可能与形态和结构相关联 单个突触传播特性的元素。使用OQA的研究显示了更大的 突触传播的多样性，甚至在相邻的突触中，都比以前认为的。冒险 高分辨率的OQA，例如在我们的实验室中开发的名为“ Quasor”和超分辨率结构的OQA 成像方法开辟了一个令人兴奋的领域，即能够研究神经活动的形状（并且是 由突触多样性塑造，分子决定剂和机制是什么，设定了这种多样性，以及 这些分子决定剂如何塑造突触多样性。 通过使用OQA，我们已经表明，通过合成强度差异来衡量的合成多样性（即 动作电位的概率引起的传播； PR）在一个单一的异质性（PR：0.01-0.5） 神经元突触到单个目标细胞上。这种高度的异质性使我们进入了中心假设 在我的论文中，突触强度是由非常精确的关键蛋白质的局部分布来设定的。测试这个 假设我将使用谷氨酸能突触 - 嗜血杆菌的模型 （NMJ） - 我将在其中研究数百个平行，体内的突触，并解决突触异质性 从单个突触分辨率（50-100nm）处的功能和结构角度来看。对于我的论文我是 接受突触生理，蝇遗传学和高级超分辨率功能/结构成像的训练 和分析。在我的论文的目标1中，我将在体内建立功能性突触异质性的程度 使用Quasor的突触。具体而言，我已经完成了研究的初步实验 基础突触异质性并解决突触基础强度（基底PR）和 突触适应较高的频率。通过超级分辨率的结构成像实验提出的 对于AIM 2，我将研究突触中的一些关键蛋白质，并确定它是否是局部数量， 它们之间的相对抽象（比率）和/或突触中突触的纳米定位 多样性。最后，对于AIM 3，通过慢性和急性操纵，我将确定UNC-13A在 塑造这种多样性。通过超级分辨率结构和功能成像的结合， 建议的工作将对可能塑造突触多样性的分子确定剂产生急需的见解。