Neuronal cell recognition in Drosophila

轴突和树突投射分离成不同的突触单位是神经系统组织的基本原则，也是大脑信息处理的结构基础。允许投射神经元识别其突触伙伴并启动突触发生的分子机制在很大程度上是未知的。利用果蝇视觉和嗅觉系统的系统遗传镶嵌方法，我们已经确定了不同的控制机制，这些机制对于感觉轴突连接到正确的中枢神经系统伙伴神经元至关重要。本应用中提出的研究旨在了解细胞识别特异性的分子基础，细胞识别特异性协调多种神经元亚型组装成功能不同的微电路。为此，我们打算在视觉和嗅觉系统之间的比较方法中探索神经元识别身份产生的两种不同发育机制的分子基础。首先，通过确定锌指蛋白红杉在投射光感受器神经元中的时间表达动态如何控制层特异性神经支配。其次，通过表征染色质调节因子Psc如何协调嗅觉神经元的感觉和突触身份的分化。从这些分析中，我们期望更好地理解大脑神经网络的特异性是如何在基因组中编码的。

The segregation of axon and dendrite projections into distinct synaptic units is a fundamental principle of nervous system organization and the structural basis for information processing in the brain. The molecular mechanisms that allow projecting neurons to recognize their synaptic partners and initiate synaptogenesis are largely unknown. Using a systematic genetic mosaic approach in the Drosophila visual and olfactory system, we have identified distinct control mechanisms, which are critical for sensory axons to connect to their correct CNS partner neurons. The research proposed in this application is aimed at understanding the molecular basis of cellular recognition specificity that coordinates the assembly of multiple neuronal subtypes into functionally distinct microcircuits. To this end we intend to explore, in a comparative approach between the visual and the olfactory system, the molecular basis of two different developmental mechanisms for the generation of neuronal recognition identity. First, by determining how the temporal expression dynamics of the Zn finger protein Sequoia in projecting photoreceptor neurons controls layer specific innervation. And second, by characterizing how the chromatin regulator Psc coordinates the differentiation of sensory and synaptic identity of olfactory neurons. From these analyses we are expecting to obtain a better understanding of how the specificity of neural brain networks is encoded in the genome.