Functional characterization of neurons in the Drosophila medulla, which is the first processing center for color vision, using a behavioural assay

眼睛的功能之一是检测环境中的颜色信息。在果蝇中，内部的光感受器细胞R7和R8专门完成这一任务，而外部的光感受器细胞R1-R6参与运动检测。R1-R6投射到视叶的外层，板层，而R7和R8投射到更深的层，髓质。延髓含有约20,000个神经元，属于至少17种不同的细胞类型，被认为是颜色视觉的主要处理中心。然而，单个细胞类型的功能仍不清楚。虽然宿主实验室目前正在表征延髓的连通性，并正在重建电路的解剖结构，但分析每种细胞类型的功能是重要的。我建议使用宿主实验室与维尔茨堡的海森堡实验室合作建立的颜色视觉行为测试来对不同类别的延髓神经元进行功能表征。为了实现这一目标，我将开发工具，允许我专门操纵延髓中每种特定细胞类型的神经元活动。然后，我将抑制个别类别的延髓神经元，并测试各自的苍蝇在行为测试中区分蓝光和绿光的能力。这项拟议的研究将为果蝇延髓的解剖图谱增加功能数据，并将为深入了解大脑中颜色信息处理的机制提供洞察。

One of the functions of the eye is the detection of color information in the environment. In Drosophila, the inner photoreceptor cells R7 and R8 are specialized for this task, while the outer photoreceptors R1-R6 are involved in motion detection. R1-R6 project to the outer part of the optic lobe, the lamina, while R7 and R8 target a deeper layer, the medulla. The medulla contains ~20,000 neurons belonging to at least 17 different cell types and is thought to be the main processing center for color vision. However, the function of the individual cell types is still unknown. While the host lab is currently characterizing connectivity in the medulla, and is reconstructing the anatomy of the circuitry, it is important to analyze the function of each cell type. I propose to functionally characterize different classes of medulla neurons by using a color vision behavioral assay that has been established in the host lab, in collaboration with the Heisenberg lab in Würzburg. In order to achieve this goal, I will develop tools that allow me to manipulate neuronal activity exclusively in each particular cell type in the medulla. I will then inhibit individual classes of medulla neurons and test the respective flies for their ability to discriminate between blue and green light in a behavioral assay. The proposed study will add functional data to the anatomical map of the Drosophila medulla and will provide insight into the mechanism of color information processing in the brain.