果蝇中央脑蘑菇体与椭球体神经功能联结

Having both simple nervous system and complex cognition activities at the same time, Drosophila melanogaster is probably the first model organism to be depicted out the whole nervous system-cognitive activity map in a decade or two, and therefore favored by a lot of neural biologists. Plasticity -dependent learning and memory behavior is the base for all cognitive activity, and researches on it are the very highlight of booming brain programs in recent years. Our previous results show that there may exist bi-directional synaptic connections between mushroom body, the olfactory center, and ellipsoid body, which is in charge of visual learning and memory. To further verify the existence of these synapses, we will take advantage of the recently-developed super-resolution fluorescent microscopy to observe the possible synaptic connections. Also we’ll trace out single ellipsoid body neurons through its distinct morphology by sequential scanning electron microscopy to look for evidence of synaptic connection between ellipsoid body neuron and mushroom body Kenyon cell. As for the functional connection between these two brain structures, we’ll activate several ellipsoid body neurons via opto-genetic or thermal-genetic methods and simultaneously record the neural activity from both of the two groups of neurons to explore the relationship between them. This work may for the first time reveal the network of interacting mushroom body and ellipsoid body neurons, and may also develop new methods for research on neural circuit-neural activity, and thus we see both scientific significance and application prospect on it.

果蝇兼有相对简单的神经系统（约9万个神经元）与相对复杂的认知行为活动，因可能描绘出完整的神经结构-认知功能图谱而倍受神经生物学家青睐。而可塑性依赖的学习记忆作为一切认知活动的基础，在近来兴起的脑研究计划中占有重要地位。我们之前的研究表明，果蝇中央脑中嗅觉学习记忆中枢蘑菇体与负责调控视觉记忆的椭球体之间可能存在双向的突触联结。为了进一步证实这些突触联结是否存在，我们计划利用荧光超分辨显微成像来观察这些可能产生突触联结的区域，同时结合连续扫描电镜技术来追踪单个椭球体神经元进而寻找其与蘑菇体神经元之间突触存在的证据。在功能上，我们将利用光/热遗传学的手段来特异性地激活少量椭球体神经元，通过实时功能成像来分析椭球体与蘑菇体神经元活动之间的关系。以上工作将首次从神经网络水平揭示果蝇不同高级认知结构之间的关系，同时有可能发展出神经结构-功能图谱研究的新技术与方法，具有重要的科学意义与应用价值。