Coordination and propagation of cell fate choice in neural circuit assembly

神经回路组装中细胞命运选择的协调和传播

• 批准号: 10230499
• 负责人: Yu-Chieh Chen
• 金额: $ 6.6万
• 依托单位: NEW YORK UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-07-01 至 2024-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10230499
• 关键词: Address; Area; Axon; Bioinformatics; Cell Adhesion Molecules; Cell surface; Cells; Clustered Regularly Interspaced Short Palindromic Repeats; Code; Color; Color Visions; Data; Detection; Development; Developmental Biology; Diffuse intrinsic pontine glioma; Distal; Drosophila genus; Ensure; Event; Eye; Face; Generations; Genes; Genetic; Human; Immunoglobulins; Interneurons; Invertebrates; Knowledge; Logic; Mediating; Modeling; Molecular; Motion; Neurodegenerative Disorders; Neurons; Neuropil; Neurosciences; Olfactory Pathways; Optic Lobe; Pathway interactions; Pattern; Peripheral; Photoreceptors; Population; Production; Proteins; Reagent; Retina; Rodent; Role; Sensory; Site; Sorting - Cell Movement; Specific qualifier value; Specificity; Synapses; System; Technology; Testing; Training; Transgenic Organisms; Work; Writing; axon guidance; candidate marker; cell fate specification; cell type; data dissemination; experimental study; fascinate; fly; gain of function; genetic approach; genetic manipulation; insight; member; mutant; neural circuit; neuronal circuitry; novel; novel therapeutic intervention; overexpression; programs; reconstruction; regenerative; sensory system; single cell analysis; single-cell RNA sequencing; skills; tool; transcription factor; transcriptome; transcriptome sequencing

Project Summary How vast numbers of neurons are specified into correct cell fates and connected with proper targets during development represents a fascinating area of developmental neuroscience. Mechanisms of stochastic and deterministic cell specification programs to achieve neuronal diversity have been extensively studied. Over the last decades, a number of cell surface molecules have also been identified that mediate axon guidance and connectivity. However, little is known about the coordination between neuronal specification and specific connectivity patterns, especially when two synaptic partners undergo two different modes of cell specification (stochastic vs. deterministic). The Drosophila color vision circuit is an appealing model to address this question due to our deep knowledge of its development, its precise neuronal connectivity, and the availability of powerful genetic tools for cell-type specific manipulations. In the fly retina, pale (p) and yellow (y) subtypes of color photoreceptors (R7 and R8) are stochastically specified, whereas their synaptic partners in the optic lobe are produced through highly deterministic programs. How do stochastically determined p/y R7 and R8 find their targets that are deterministically specified in the optic lobes? How is this decision propagated to their downstream targets during circuit formation? What molecules direct these events? Previous work from our lab has identified Dpr11 and DIPg, which are members of an interacting network of immunoglobulin superfamily proteins, as critical regulators of the synaptic connection between yR7 and its downstream target. We hypothesize that different pairs of cell adhesion molecules mediate the matching of other synaptic partners. By using single-cell RNA sequencing technology, CRISPR gene editing, and sophisticated genetic manipulation in the Drosophila color vision circuit, we aim to identify cell adhesion molecules that direct synaptic partner matching and the molecular logic for coordinating between cell-type specification and the synaptic connectivity at the system level. We will define the synaptic connectivity as well as generate cell-type specific transgenic reagents and higher-depth transcriptomes of relevant cell types (Aim 1). We will use a candidate approach combined with transcriptome analysis of sorted targeted neurons of color photoreceptors to identify the molecules required for synaptic partner matching (Aim 2). We will compare whether a given neuron uses the same or different molecular codes for matching its pre- and post-synaptic partners. Finally, we will study how the synaptic partner choices propagate to neurons further downstream by perturbating the cell fates of R7 and R8 (Aim 3). Successful completion of this proposal will uncover novel molecular mechanisms regulating synaptic pairing and probe the fundamental principles underlying the propagation of cell fate choices during circuit assembly. The principles identified here will be significant and applicable to other neuronal circuits facing similar developmental challenges, such as the olfactory system in rodents and color vision in humans.

项目摘要 大量神经元是如何被指定为正确的细胞命运并与正确的靶点相联系的 发展是发展神经科学中一个引人入胜的领域。随机和随机机制 实现神经元多样性的确定性细胞规范方案已经得到了广泛的研究。超过了 在过去的几十年里，一些细胞表面分子也被发现，它们介导轴突引导和 连通性。然而，对神经元规范和特异性之间的协调知之甚少。 连接模式，特别是当两个突触伙伴经历两种不同的细胞规范模式时 (随机性与确定性)果蝇的色觉回路是解决这个问题的一个有吸引力的模型 由于我们对其发展的深入了解，其精确的神经元连接，以及 强大的基因工具，可用于细胞类型的特定操作。在苍蝇视网膜中，苍白(P)和黄色(Y)亚型 彩色光感受器(R7和R8)是随机指定的，而它们在视叶的突触伙伴 都是通过高度确定性的程序产生的。随机确定的p/y R7和R8如何找到 它们的目标是在视叶中确定的吗？这一决定是如何传播给他们的 在线路形成过程中的下游目标？是什么分子指导着这些事件？我们实验室以前的工作 已经确定Dpr11和Dipg是免疫球蛋白超家族相互作用网络的成员 蛋白质，作为yr7与其下游靶标之间突触连接的关键调节因子。我们 假设不同的细胞黏附分子对调节其他突触伙伴的匹配。通过 使用单细胞RNA测序技术、CRISPR基因编辑和复杂的遗传操作 果蝇的色觉回路，我们的目标是识别直接突触伙伴的细胞黏附分子 匹配和细胞类型规范与突触连通性协调的分子逻辑 在系统级别。我们将定义突触连接以及产生特定细胞类型的转基因 相关细胞类型的试剂和更深入的转录本(目标1)。我们将使用候选方法 结合转录组分析分选的彩色光感受器靶神经元鉴定 突触配对所需的分子(目标2)。我们将比较给定的神经元是否使用 用于匹配突触前和突触后伙伴的相同或不同的分子代码。最后，我们将研究如何 突触伙伴的选择通过扰乱R7和R7的细胞命运而传播到更下游的神经元 R8(目标3)。这一提议的成功完成将揭示新的分子调控机制 突触配对和探索细胞命运选择传播的基本原理 电路组件。这里确定的原理将具有重要意义，并适用于其他神经元电路 面临着类似的发育挑战，例如啮齿动物的嗅觉系统和人类的色觉。