Neural Circuits Underlying Multisensory Control of Orientation in Drosophila

项目概要/摘要： 大脑如何结合来自不同模态的感官刺激来指导行为目前还不清楚。 在单细胞水平上理解。在这里，我们建议使用模式生物果蝇来研究 多感觉整合的神经回路基础在两种特定定向行为的背景下发展起来 在我们的实验室里。在一个范例中，气味将行走的苍蝇的方向转换为风（机械感觉）线索： 苍蝇在没有气味时顺风定向，在有吸引力的气味时逆风定向。在第二 范例中，厌恶的风刺激和吸引人的视觉刺激总和来引导系留的 飞的飞。我们发现了一种新的机械感觉通路， 苍蝇的触角的运动，并将此信息传输到中央复合体，大脑的一个区域 与航海有关。结合文献信息和我们自己的初步数据， 实验室，这表明了一个模型，不同的感觉流可能是如何对齐和整合在 中央综合体我们建议使用光遗传学激活，化学遗传学沉默，全细胞 电生理学和功能成像，以测试候选中枢复合神经元在多- 方向感控制。我们还将测试另一种假设，即多感官 这两种行为需要下行神经元的整合。这项研究将提供一个全面的 细胞水平的解释如何感觉流相结合，以控制一个模式生物的方向。

Project Summary/Abstract: How the brain combines sensory stimuli from different modalities to guide behavior is currently not understood at a single-cell level. Here we propose to use the model organism Drosophila to investigate the neural circuit basis of multi-sensory integration in the context of two specific orientation behaviors developed in our lab. In one paradigm, odor switches the orientation of walking flies to a wind (mechanosensory) cue: flies orient downwind in the absence of odor and upwind in the presence of an attractive odor. In the second paradigm, an aversive wind stimulus and attractive visual stimulus sum to guide orientation of a tethered flying fly. We have discovered a novel mechanosensory pathway that computes wind direction from movements of the fly's antennae, and transmits this information to the central complex, a region of the brain implicated in navigation. Combined with information from the literature and preliminary data from our own lab, this suggests a model for how different sensory streams might be aligned and integrated within the central complex. We propose to use optogenetic activation, chemogenetic silencing, whole-cell electrophysiology, and functional imaging to test the role of candidate central complex neurons in multi- sensory control of orientation. We will additionally test the alternative hypothesis that multi-sensory integration in descending neurons is required for the two behaviors. This study will provide a comprehensive cellular-level account of how sensory streams are combined to control the orientation of a model organism.