Mapping the optic lobes for color vision

项目摘要 本提案是5 R 01 EY 017916 -04“色觉视叶标测”的更新。视觉 果蝇眼睛收集的信息首先在视叶、视板、视髓和视小叶中处理 复杂.髓质是色觉神经网络中的第一个中继，但它是色觉神经网络中的第二步。 运动检测路径。在上一个授予期间，我们已经定义了70多种细胞类型， 在投射到小叶复合体之前重叠视网膜定位图。因为髓质含有有限的 神经元和连接的数量，可以在精致的细节研究，我们可以解决基本的 关于复杂神经结构的发展和功能的问题。我们提出的实验， 了解视神经元多样性是如何产生的，以及这些神经元如何建立其视网膜定位 与感光细胞的联系这将产生知识和工具，我们将使用这些知识和工具来分析 通过电生理学和行为测定，观察单个神经元在视通路中的功能。三个具体 目标将帮助我们实现这些目标。（一）.顺序成神经细胞（NB）转换产生神经元 多样性我们已经发现，NBs作为一种分化波从髓质产生， 神经上皮在与序列相似的过程中顺序表达至少三种转录因子 在胚胎NB中观察到。从这些NB中出现的神经元维持这些基因的表达， 变成不同的细胞类型。我们将确定新的NB和神经元标记物，并确定成人神经元细胞 由TF的组合标记的来自幼虫神经元的类型。 （二）、髓质神经上皮的区域化和成神经细胞的特化。神经元的类型 由顺序产生的NB产生的不同区域的新月形髓质外 增殖中心（OPC）。在中央部分，年轻的NB产生局部柱状细胞， 它们产生了，以及少量的非柱状神经元迁移到占据它们的神经元。 在整个成人髓质中的视网膜定位位置。我们将分析NB的谱系如何被它们的 沿着OPC定位。然后，我们将操纵NB的位置恒等式并分析其结果 对髓质神经元组成的影响。因此，我们将定义组合转录因子编码 指定髓质神经元类型，并将其与它们的成年命运相关联。（三）、个别髓质的功能 神经元我们将记录这些神经元对各种光刺激的电生理活动。我们 我将继续我们对参与运动检测的神经元的分析，并扩展对延髓神经元的分析 参与了染色质通路。在目标1和2中产生的工具将允许我们沉默或刺激这些 神经元通过“交叉”表达来分析苍蝇的运动和颜色行为， 模拟器

PROJECT SUMMARY This proposal is a renewal of 5R01EY017916-04 "Mapping the optic lobes for color vision". Visual information gathered by the Drosophila eye is first processed in the optic lobes, lamina, medulla and lobula complex. The medulla is the first relay in the neural network for color vision, but it is the second step in the motion detection pathway. In the previous granting period, we have defined over 70 cell types that form overlapping retinotopic maps before projecting to the lobula complex. Because the medulla contains a finite number of neurons and connections that can be studied in exquisite detail, we can address fundamental questions about the development and function of a sophisticated neural structure. We present experiments to understand how optic neuron diversity is generated and how these neurons establish their retinotopic connections to photoreceptors. This will produce knowledge and tools that we will then use to analyze the function of individual neurons in optic pathways through electrophysiology and behavior assays. Three specific aims will help us reach these goals. (1). Sequential neuroblast (NB) switching generates neuronal diversity. We have discovered that the NBs generated as a wave of differentiation from the medulla neuroepithelium express sequentially at least three transcription factors in a process similar to the sequence observed in embryonic NBs. The neurons emerging from these NBs maintain expression of these genes and become different cell types. We will identify new NB and neuronal markers and identify the adult neuronal cell types derived from larval neurons marked by combinations of TFs. (2). Regionalization of medulla neuroepithelium and specialization of neuroblasts. The types of neurons generated by the sequentially generated NBs differ in distinct regions of the crescent shaped medulla Outer Proliferation Center (OPC). In the central part, young NBs produce both local columnar cells that remain where they were generated, as well as a smaller number of non-columnar neurons that migrate to occupy their retinotopic position in the entire adult medulla. We will analyze how the lineage of NBs is modified by their position along the OPC. We will then manipulate the positional identity of NBs and analyze the consequence on the neuronal composition of the medulla. We will thus define the combinatorial transcription factor code specifying medulla neuron types and will relate it to their adult fates. (3). Function of individual medulla neurons. We will record electrophysiological activity of these neurons in response to various light stimuli. We will continue our analysis of neurons involved in motion detection and extend this analysis of medulla neurons involved in chromatic pathways. The tools generated in aims 1 and 2 will allow us to silence of stimulate these neurons through 'intersectional' expression to analyze the motion and color behavior of flies using our flight simulator.