Wagner Nicole
Institute of Anatomy and Cell Biology, Julius-Maximilians University Wuerzburg, Koellikerstraße 6, Wuerzburg, Germany.
J Morphol. 2017 Jul;278(7):987-996. doi: 10.1002/jmor.20692. Epub 2017 Apr 26.
Drosophila melanogaster has recently emerged as model system for studying synaptic transmission and plasticity during adulthood, aging and neurodegeneration. However, still little is known about the basic neuronal mechanisms of synaptic function in the adult fly. Per se, adult Drosophila neuromuscular junctions should be highly suited for studying these aspects as they allow for genetic manipulations in combination with ultrastructural and electrophysiological analyses. Although different neuromuscular junctions of the adult fly have been described during the last years, a direct ultrastructural comparison with their larval counterpart is lacking. The present study was designed to close this gap by providing a detailed ultrastructural comparison of the larval and the adult neuromuscular junction of the ventrolongitudinal muscle. Assessment of several parameters revealed similarities but also major differences in the ultrastructural organisation of the two model neuromuscular junctions. While basic morphological parameters are retained from the larval into the adult stage, the analysis discovered major differences of potential functional relevance in the adult: The electron-dense membrane apposition of the presynaptic and postsynaptic membrane is shorter, the subsynaptic reticulum is less elaborated and the number of synaptic vesicles at a certain distance of the presynaptic membrane is higher.
黑腹果蝇最近已成为研究成年期、衰老期和神经退行性变过程中突触传递和可塑性的模型系统。然而，对于成年果蝇突触功能的基本神经元机制仍知之甚少。就其本身而言，成年果蝇的神经肌肉接头应该非常适合研究这些方面，因为它们允许将基因操作与超微结构和电生理分析相结合。尽管在过去几年中已经描述了成年果蝇的不同神经肌肉接头，但缺乏与其幼虫对应物的直接超微结构比较。本研究旨在通过提供腹纵肌幼虫和成年神经肌肉接头的详细超微结构比较来填补这一空白。对几个参数的评估揭示了两种模型神经肌肉接头超微结构组织中的相似之处，但也存在主要差异。虽然基本形态学参数从幼虫期保留到成年期，但分析发现成年期存在潜在功能相关性的主要差异：突触前膜和突触后膜的电子致密膜附着较短，突触下网不太发达，突触前膜一定距离处的突触小泡数量较多。
