Scalable electron tomography for connectomics

用于连接组学的可扩展电子断层扫描

• 批准号: 10410742
• 负责人: Mark H Ellisman
• 金额: $ 291.62万
• 依托单位: HARVARD MEDICAL SCHOOL
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-07-15 至 2025-07-14
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10410742
• 关键词: Address; Affect; Anatomy; Brain; Cells; Cerebellar Cortex; Cerebellar Nuclei; Cerebellum; Chemical Synapse; Chemicals; Collection; Computer Models; Computer software; Coupling; Data Set; Development; Electrical Synapse; Electron Beam; Electron Microscopy; Electrons; Elements; Engineering; Foundations; Gap Junctions; Goals; Image; Label; Machine Learning; Mechanics; Methods; Microscopic; Microtomy; Modeling; Modernization; Molecular Genetics; Morphology; Mus; Nervous system structure; Neurodegenerative Disorders; Neurons; Neurosciences; Optics; Physiology; Purkinje Cells; Reporter; Research; Resolution; Resources; Reverse engineering; Role; Scanning; Scanning Electron Microscopy; Series; Social Behavior; Specificity; Speed; Structure; Synapses; System; Techniques; Testing; Thick; Thinness; Transmission Electron Microscopy; Work; advanced system; base; cell type; cognitive function; comparative; connectome; connexin 36; effective therapy; electron optics; electron tomography; method development; motor control; nanoscale; network models; neural circuit; neural network; neuronal circuitry; next generation; novel; reconstruction; sample collection; tomography; tool; treatment strategy; voltage

Project Summary / Abstract A fundamental goal in neuroscience is understanding how neural network function arises from circuit structure. However, the immense complexity of most brain networks has been a significant barrier to progress. We do not have a comprehensive wiring diagram for any mammalian local circuit, much less a whole brain. We do not yet have a comprehensive list of cell types and how they are defined for even the simplest mammalian neuronal circuit. Moreover, synapse resolution connectomics has focused almost entirely on chemical synapses and ignored electrical synapses formed by gap junctions, which are thought to be crucial for network synchrony and oscillations. Recent advances in automated sample collection and imaging for transmission electron microscopy (TEM) and molecular genetic tools have allowed us to begin detailed mapping of neural network anatomy. Development of intermediate voltage TEMs has demonstrated the ability to volumetrically image through thick (~1 μm) sections with high resolution tomography. Here, we propose combining automated sample collection and imaging using GridTape, with electron microscopic tomography (EMT) and conical beam procession “VortexBeam” imaging. This new combination of approaches will increase both the resolution and throughput of connectomics, while decreasing the number of sections that need to be collected and acquired. The cerebellum is an ideal system to validate our novel platform as part of a systematic effort to reverse engineer a functional neural circuit that is involved in motor control and social behavior. Its basic structure is well ordered, relatively simple and sufficiently described to have inspired computational models that capture aspects of cerebellar function. However, even the most advanced models are limited by an incomplete characterization of the cell types and connectivity within the cerebellum. Here, we propose to validate our next-generation EMT platforms and characterize long-range, local, and gap junctional connectivity in the cerebellum. We will combine tools recently developed in our labs to a circuit that offers the advantages of relative simplicity and a strong starting foundation. These studies will allow us to understand principles of cerebellar circuit organization and may help us determine the role of specific circuit elements in neurodegenerative disorders.

项目总结/摘要 神经科学的一个基本目标是了解神经网络功能如何从电路结构中产生。 然而，大多数大脑网络的巨大复杂性一直是进步的重大障碍。我们不 对于任何哺乳动物的局部电路都没有一个全面的布线图，更不用说整个大脑了。我们还不 我有一个全面的细胞类型列表，以及它们是如何定义的，即使是最简单的哺乳动物神经元 电路.此外，突触分辨连接组学几乎完全集中在化学突触上， 忽略了由缝隙连接形成的电突触，这被认为是网络同步的关键， 振荡透射电子显微镜样品自动采集和成像技术的最新进展 (TEM)分子遗传学工具使我们能够开始详细绘制神经网络解剖图。 中等电压TEM的发展已经证明了通过厚膜的体积成像的能力。 （~1 μm）切片，高分辨率断层扫描。在这里，我们建议将自动化样本采集 和成像使用GridTape，电子显微镜断层扫描（EMT）和锥形束处理 “VortexBeam”成像这种新的方法组合将提高分辨率和吞吐量 连接组学，同时减少需要收集和获取的部分的数量。小脑 是一个理想的系统，以验证我们的新平台，作为系统性工作的一部分， 参与运动控制和社会行为的神经回路。它的基本结构相对来说是有序的 简单和充分的描述，激发了计算模型，捕捉小脑的各个方面， 功能然而，即使是最先进的模型也受到细胞不完整表征的限制 小脑内的类型和连接。在这里，我们建议验证我们的下一代EMT平台 并表征小脑中的长距离、局部和缝隙连接。我们将联合收割机工具 最近在我们的实验室开发的电路，提供了相对简单的优势和强大的启动 基金会这些研究将使我们了解小脑回路组织的原理， 我们确定特定回路元件在神经退行性疾病中的作用。