Sun Mingkuan, Zeng Xiankun, Xie Wei
The Key Laboratory of Developmental Genes and Human Disease, Institute of Life Sciences, Southeast University, Nanjing, 210096, China.
Sci China Life Sci. 2016 Jan;59(1):68-77. doi: 10.1007/s11427-015-4946-9. Epub 2015 Oct 26.
Drosophila neurexin (DNRX) plays a critical role in proper architecture development and synaptic function in vivo. However, the temporal and spatial expression pattern of DNRX still remains unclear. For this study, we generated a novel Drosophila transgenic strain termed the DNRX-Gal4 transgenic line, with characteristic features in agreement with the endogenous DNRX expression pattern. DNRX expression was examined by driving the expression of a GFP reporter (nuclear-localized and membrane- localized GFP) using the DNRX-Gal4 promoter. We found that DNRX was expressed preferentially in central and motor neurons in embryos, larvae and adults, but not in glial cells. DNRX was expressed in pre- and post-synaptic areas in third instar larvae neuromuscular junctions (NMJs). Reporter expression was also observed in the salivary glands, guts, wings and legs of adult flies. In the adult brain, reporter expression was observed throughout several brain regions, including the mushroom body (MBs), antennal lobe (AL) and optic lobe neurons, which is consistent with endogenous DNRX expression via antibody staining. Interestingly, DNRX was also expressed in clock neurons. Meanwhile, we found that DNRX expression in the MBs was required for olfactory learning and memory.
果蝇神经连接蛋白（DNRX）在体内正常的结构发育和突触功能中起着关键作用。然而，DNRX的时空表达模式仍不清楚。在本研究中，我们构建了一种新型的果蝇转基因品系，称为DNRX-Gal4转基因系，其特征与内源性DNRX表达模式一致。通过使用DNRX-Gal4启动子驱动绿色荧光蛋白（GFP）报告基因（核定位和膜定位GFP）的表达来检测DNRX的表达。我们发现，DNRX在胚胎、幼虫和成虫的中枢神经元和运动神经元中优先表达，但在神经胶质细胞中不表达。DNRX在三龄幼虫神经肌肉接头（NMJ）的突触前和突触后区域表达。在成年果蝇的唾液腺、肠道、翅膀和腿部也观察到报告基因的表达。在成年果蝇大脑中，在包括蘑菇体（MB）、触角叶（AL）和视叶神经元在内的几个脑区都观察到了报告基因的表达，这与通过抗体染色检测到的内源性DNRX表达一致。有趣的是，DNRX也在时钟神经元中表达。同时，我们发现MB中DNRX的表达是嗅觉学习和记忆所必需的。
