Fabritius-Vilpoux Kathia, Bisch-Knaden Sonja, Harzsch Steffen
Fakultät für Naturwissenschaften, Institut für Neurobiologie, Universität Ulm, Albert-Einstein-Allee 11, 89069, Ulm, Germany.
Invert Neurosci. 2008 Dec;8(4):177-97. doi: 10.1007/s10158-008-0081-7. Epub 2008 Nov 13.
The homeobox transcription factor Engrailed is involved in controlling segmentation during arthropod germ band formation but also in establishing individual neuronal identities during later embryogenesis. In Crustacea, most studies analysing the expression of Engrailed so far have focussed on its function as segment polarity gene. In continuation to these previous studies, we analysed the neuronal expression of the Engrailed protein by immunohistochemistry in the embryonic nerve cord of a parthenogenetic crustacean, the Marbled Crayfish (Marmorkrebs). We paid particular attention to the individual identification of Engrailed expressing putative neuroblasts in the crayfish embryos. Engrailed positive cells in the neuroectoderm were counted, measured and mapped from 38 to 65% of embryonic development. That way, several Engrailed positive putative neuroblasts and putative neurons were identified. Our findings are compared with earlier studies on Engrailed expression during germ band formation in Crustacea. Recent data on neurogenesis in an amphipod crustacean have provided compelling evidence for the homology of several identified neuroblasts between this amphipod and insects. The present report may serve as a basis to explore the question if during crustacean neurogenesis additional communalities with insects exist.
同源异型框转录因子En（Engrailed）参与节肢动物胚带形成过程中的体节控制，也参与后期胚胎发育过程中个体神经元身份的建立。在甲壳纲动物中，目前大多数分析En表达的研究都集中在其作为体节极性基因的功能上。在这些先前研究的基础上，我们通过免疫组织化学分析了孤雌生殖的甲壳动物大理石纹螯虾胚胎神经索中En蛋白的神经元表达。我们特别关注小龙虾胚胎中表达En的假定神经母细胞的个体识别。在胚胎发育的38%至65%阶段，对神经外胚层中En阳性细胞进行计数、测量和定位。通过这种方式，识别出了几个En阳性的假定神经母细胞和假定神经元。我们的研究结果与早期关于甲壳纲动物胚带形成过程中En表达的研究进行了比较。最近关于一种双足甲壳动物神经发生的数据为该双足甲壳动物和昆虫之间几个已识别神经母细胞的同源性提供了有力证据。本报告可作为探讨甲壳动物神经发生过程中是否存在与昆虫的其他共性这一问题的基础。
