Biology Department, Grinnell College, Grinnell, IA, USA.
Chemistry Department, Grinnell College, Grinnell, IA, USA.
J Neurochem. 2021 Jan;156(1):38-47. doi: 10.1111/jnc.15173. Epub 2020 Sep 21.
N-acetylaspartylglutamate (NAAG) is a common neurotransmitter in the mammalian nervous system; however, it has never been reported in the nervous system of the fruit fly, Drosophila melanogaster. Using antiserum against NAAG, we localized NAAG-like immunoreactivity to neurons in the ventral nerve cord and to type Is glutamatergic nerve terminals in larval neuromuscular junctions. Using liquid chromatography tandem mass spectrometry (LC-MS), we failed to find NAAG but found the related peptide N-acetylaspartylglutamylglutamate (NAAG ) in Drosophila CNS and body wall tissue. This is the first report of any NAAG-family peptide in the nervous system of Drosophila and is also the first report of NAAG being present in a much higher concentration than NAAG in the nervous system of any species. Thus, the larval fruit fly presents an interesting model for the study of the functional role of NAAG of which very little is known-especially in the absence of an abundance of NAAG.
N-乙酰天门冬酰谷氨酸（NAAG）是哺乳动物神经系统中的一种常见神经递质；然而，它从未在果蝇的神经系统中被报道过。使用针对 NAAG 的抗血清，我们将 NAAG 样免疫反应性定位到腹神经索中的神经元以及幼虫肌肉神经节中的 I 型谷氨酸能神经末梢。使用液相色谱串联质谱（LC-MS），我们未能找到 NAAG，但在果蝇中枢神经系统和体壁组织中发现了相关肽 N-乙酰天门冬酰谷氨酸酰谷氨酸（NAAG）。这是 NAAG 家族肽在果蝇神经系统中的首次报道，也是 NAAG 在任何物种的神经系统中存在的浓度比 NAAG 高得多的首次报道。因此，幼虫果蝇为研究 NAAG 的功能作用提供了一个有趣的模型，而关于 NAAG 的功能作用，我们知之甚少——尤其是在缺乏大量 NAAG 的情况下。
