Controlling neural circuits with single-cell resolution in behaving animals

以单细胞分辨率控制行为动物的神经回路

基本信息

批准号：
9275048
负责人：
Christopher Fang-Yen
金额：
$ 35万
依托单位：
UNIVERSITY OF PENNSYLVANIA
依托单位国家：
美国
项目类别：
财政年份：
2013
资助国家：
美国
起止时间：
2013-08-15 至 2019-05-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9275048
关键词：
Algorithms Alpha Cell Animal Model Animals Architecture Axon Behavior Behavior monitoring Biogenic Amines Biological Models Biomedical Engineering Brain Caenorhabditis elegans Calcium Cells Code Computer software Darkness Data Dendrites Development Devices Dimensions Disease Dissection Dopamine Drosophila genus Feedback Financial compensation Fluorescence Food Future Genetic Genetic Models Goals Image Individual Ion Channel Ion Pumps Label Laboratories Larva Lasers Light Lighting Locomotion Methods Modeling Movement Nematoda Nerve Nerve Degeneration Nervous system structure Neurological Models Neurology Neurons Neurotransmitters New York Opsin Optics Organism Pathway interactions Pattern Pennsylvania Performance Process Reagent Resolution Role Serotonin Shapes Signal Transduction Speed Structure Swimming Synapses Synaptic Transmission System Techniques Technology Testing Time Universities Varicosity Vision Work Zebrafish awake base behavioral study design digital dopaminergic neuron experimental study fluorescence imaging image processing improved instrumentation mutant nervous system disorder neural circuit neuron development neuronal cell body neuroregulation new technology next generation optogenetics prediction algorithm public health relevance relating to nervous system spatiotemporal tool

项目摘要

DESCRIPTION (provided by applicant): Neural circuits are the fundamental functional units of the nervous system. A basic understanding of circuit function will provide an important basis for understanding how these circuits malfunction in neurological disorders. The study of neural circuits in small and relatively simple model animals such as C. elegans and Drosophila has many advantages, including genetic manipulability and amenability to optical techniques. Circuit analysis in these organisms has been buoyed by the recent development of 'optogenetic' methods for stimulating and inhibiting neural activity using light-sensitive ion channels and pumps [1]. Progress in optogenetics requires not only development and optimization of new opsin molecules but also new strategies and technologies for perturbing specific opsin-expressing neurons. In this project, we will develop optical and genetic methods for manipulating neural circuits with single- neuron resolution in freely moving C. elegans. This project extends previous work by Dr. Fang-Yen, in which machine vision algorithms and lasers patterned by a digital micromirror device (DMD) were used to achieve spatiotemporal control of neural activity in freely behaving worms [2]. This earlier system was limited to a spatial resolution of about 20-30 microns, which is insufficient to selectively illuminate single neurons in the animal's nerve ring (brain). In this project we will develop a next-generation system capable of resolving single neurons and subcellular features. We will approach this goal in three directions. First, we will develop instrumentation and machine vision algorithms to automatically image and track individual neurons and processes using fluorescence imaging. We will use a dual-magnification optical system to simultaneously track behavior of the entire worm and fluorescence in a smaller region. Second, we will design and implement predictive algorithms to illuminate tracked targets with compensation for the latency due to image processing and data transfer. This system will be designed with real-time feedback such that fine-tuning of its parameters can be done in an automated manner. Third, we will use our system, in combination with other methods, to elucidate the mechanisms of modulation of locomotory behaviors by dopaminergic and serotonergic circuits. By enabling, for the first time, the dynamic perturbation of individual or multiple neurons in a behaving animal, the technology we develop will become an important tool for the analysis of neural circuits, with numerous advantages compared with existing methods. In addition to improving our understanding of the circuit basis of behavior, these studies will help provide a circuit-level context for interpreting genetic mutants, for example in C. elegans models of synaptic transmission, neuronal development, and neurodegeneration. While the focus of this project is on C. elegans, we expect that our methods will be readily extensible to other model organisms. This project will be centered in Dr. Fang-Yen's laboratory but will draw on the expertise of several unpaid consultants at the University of Pennsylvania or nearby. These include Dr. David Raizen (Dept. of Neurology), an expert in C. elegans genetics and behavior, Dr. Brian Chow (Dept. of Bioengineering), an expert on optogenetic reagents, and Dr. Niels Ringstad (New York University), an expert in C. elegans genetics and neurotransmitter signaling.

描述（由申请人提供）：神经回路是神经系统的基本功能单元。对回路功能的基本了解将为理解这些回路在神经系统疾病中如何发生故障提供重要基础。对小型且相对简单的模型动物（例如线虫和果蝇）的神经回路进行研究具有许多优点，包括遗传可操作性和光学技术的适用性。最近使用光敏离子通道和泵刺激和抑制神经活动的“光遗传学”方法的发展推动了这些生物体的电路分析[1]。光遗传学的进展不仅需要开发和优化新的视蛋白分子，还需要扰乱特定表达视蛋白的神经元的新策略和技术。在这个项目中，我们将开发光学和遗传方法，以单神经元分辨率操纵自由移动的秀丽隐杆线虫的神经回路。该项目扩展了 Fang-Yen 博士之前的工作，其中使用机器视觉算法和数字微镜设备 (DMD) 图案化的激光来实现对自由行为蠕虫神经活动的时空控制 [2]。这种早期系统的空间分辨率仅限于约 20-30 微米，不足以选择性地照亮动物神经环（大脑）中的单个神经元。在这个项目中，我们将开发一种能够解析单个神经元和亚细胞特征的下一代系统。我们将从三个方向实现这一目标。首先，我们将开发仪器和机器视觉算法，以使用荧光成像自动成像和跟踪单个神经元和过程。我们将使用双放大光学系统来同时跟踪整个蠕虫的行为和较小区域中的荧光。其次，我们将设计和实现预测算法来照亮跟踪目标，并补偿图像处理和数据传输造成的延迟。该系统将设计为具有实时反馈，以便可以自动方式对其参数进行微调。第三，我们将使用我们的系统与其他方法相结合，阐明多巴胺能和血清素能回路调节运动行为的机制。通过首次实现行为动物中单个或多个神经元的动态扰动，我们开发的技术将成为分析神经回路的重要工具，与现有方法相比具有许多优势。除了提高我们对行为的电路基础的理解之外，这些研究还将有助于提供用于解释的电路级上下文基因突变体，例如线虫突触传递、神经元发育和神经变性模型中的突变体。虽然该项目的重点是秀丽隐杆线虫，但我们预计我们的方法将很容易扩展到其他模式生物。该项目将以方彦博士的实验室为中心，但将利用宾夕法尼亚大学或附近几位无偿顾问的专业知识。其中包括秀丽隐杆线虫遗传学和行为专家 David Raizen 博士（神经病学系）、光遗传学试剂专家 Brian Chow 博士（生物工程系）和 Niels Ringstad 博士（纽约大学），秀丽隐杆线虫遗传学和神经递质信号传导专家。