Secondary neurons are arrested in an immature state by formation of epithelial vesicles during neurogenesis of the spider Cupiennius salei.
Secondary neurons are arrested in an immature state by formation of epithelial vesicles during neurogenesis of the spider Cupiennius salei.
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DOI：
10.1186/1742-9994-1-3
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发表时间：
2004-10-25
影响因子：
2.8
通讯作者：
Stollewerk A
中科院分区：
文献类型：
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作者：
Stollewerk A
在蜘蛛Cupiennius salei约30组神经前体产生的每半节在早期神经发生。腹侧神经节的初级神经前体组内陷后的分析表明，次级神经前体出现在胚胎发育后期，部分不分化，直到幼虫阶段。与初级组相反，次级内陷细胞在内陷后不会彼此分离，而是保持其上皮特征并形成所谓的上皮囊泡。如染料标记所示，上皮囊泡内的次级神经前体不显示任何分化的形态学特征，表明内陷后上皮囊泡的形成导致相应神经前体分化的延迟。大约一半的次级神经前体群在胚胎发生过程中不相互分离，这表明它们为幼虫和成虫阶段提供神经前体。次级神经前体通过上皮小泡的形成而被阻止在未成熟状态。这一机制有利于胚胎发育过程中幼虫神经前体的产生。我讨论了进化过程中发生的变化，在节肢动物组神经前体形成，并提出了一个模型的基本模式的神经发生。
In the spider Cupiennius salei about 30 groups of neural precursors are generated per hemi-segment during early neurogenesis. Analysis of the ventral neuromeres after invagination of the primary neural precursor groups revealed that secondary neural precursors arise during late embryogenesis that partially do not differentiate until larval stages. In contrast to the primary groups, the secondary invaginating cells do not detach from each other after invagination but maintain their epithelial character and form so-called epithelial vesicles. As revealed by dye labeling, secondary neural precursors within epithelial vesicles do not show any morphological features of differentiation indicating that the formation of epithelial vesicles after invagination leads to a delay in the differentiation of the corresponding neural precursors. About half of the secondary neural precursor groups do not dissociate from each other during embryogenesis indicating that they provide neural precursors for larval and adult stages. Secondary neural precursors are arrested in an immature state by formation of epithelial vesicles. This mechanism facilitates the production of larval neural precursors during embryogenesis. I discuss the evolutionary changes that have occured during neural precursor formation in the arthropod group and present a model for the basal mode of neurogenesis.