Neural circuits in zebrafish: form, function and plasticity

 描述（由申请人提供）：我们建议将行为幼斑马鱼神经活动的全脑双光子成像与从相同动物提取的详细解剖和连接信息相结合。最终的目标是生成大脑神经回路的定量模型，解释感觉信息的动态处理以及这些回路产生的运动输出。解剖数据将通过两种互补技术生成：1）全脑EM数据集将从用于钙成像的同一条鱼制备。相应的数据集将相互配准，然后将在EM堆栈中识别功能相关的神经元集合，并通过稀疏重建分析这些子网络中的连通性。2)基于EM的连接信息将由跨突触病毒追踪技术补充。这两种用于识别突触连接的技术具有互补的优势和劣势，因此非常适合与体内双光子钙成像研究相结合。这种方法的独特之处在于，全脑钙成像、病毒追踪和EM重建这三种技术都可以在同一只动物身上完成。然后可以在特定刺激和量化行为输出的背景下分析功能，解剖和行为数据，并随后合成为理论框架。为此，我们将从简单反射行为的定量模型开始，如视动反射和视动反射，其中感觉输入到运动输出的转换相对简单且定义明确。这些基本模型将作为一个支架，可以完善和补充额外的数据，从结构功能研究的鱼在更复杂的行为分析，涉及更复杂的刺激，不同的方式和塑料的变化。因此，构建这种“虚拟鱼”的过程将是一个迭代的、开放的过程，需要研究团队的理论和实验组之间持续和双向的信息交换。

 DESCRIPTION (provided by applicant): We propose to combine whole brain 2-photon imaging of neural activity in behaving larval zebrafish with detailed anatomical and connectivity information extracted from the same animals. The final goal is to generate quantitative models of brain wide neural circuits that explain the dynamic processing of sensory information as well as the generation of motor output by these circuits. Anatomical data will be generated by two complementary technologies: 1) whole brain EM data sets will be prepared from the same fish that were used for calcium imaging. Respective data sets will be registered to each other, functionally relevant neuronal ensembles will then be identified in the EM stacks and connectivity will be analyzed in these sub-networks via sparse reconstruction. 2) EM based connectivity information will be supplemented by trans-synaptic viral tracing technology. These two technologies for identifying synaptic connections have complementary strengths and weaknesses and are thus ideally suited for combination with in-vivo 2-photon calcium imaging studies. The specific power of this approach is that all three techniques, whole brain calcium imaging, viral tracing and EM reconstruction, can be done in the same animal. Functional, anatomical and behavioral data can then be analyzed in the context of the specific stimuli and quantified behavioral output and subsequently synthesized into a theoretical framework. To that end we will start with quantitative models of simple reflex behaviors, like the optomotor and optokinetic reflex, where the transformation of sensory input to motor output is relatively straightforward and well defined. These elementary models will serve as a scaffold that can be refined and complemented by additional data from structure function studies from fish performing in more sophisticated behavioral assays that involve more complex stimuli, different modalities and plastic changes. As such the process of building such a "virtual fish" will be an iterative, open ended process that requires continuous and bidirectional exchange of information between the theoretical and experimental groups of the research team.