Namba R, Minden J S
Department of Biological Sciences and Center for Light Microscope Imaging and Biotechnology, Carnegie Mellon University, Pittsburgh, Pennsylvania, 15213, USA.
Dev Biol. 1999 Aug 15;212(2):465-76. doi: 10.1006/dbio.1999.9349.
In an attempt to study the fates of cells in the dorsal head region of Drosophila embryos at gastrulation, we used the photoactivated gene expression system to mark small numbers of cells in selected mitotic domains. We found that mitotic domain 20, which is a cluster of approximately 30 cells on the dorsal posterior surface, gives rise to various ectodermal cell types in the head, including dorsal pouch epithelium, the optic lobe, and head sensory organs, including Bolwig's organ, the larval photoreceptor organ. We found that the optic lobe and larval photoreceptors share the same origin of a few adjacent cells near the center of mitotic domain 20, suggesting that within the mitotic domain, there is a subdomain from which the larval visual system is specified. In addition to the components of the larval visual system, this central region of mitotic domain 20 also generates a part of the eye-antennal disc placode; cells that gives rise to the adult visual system. We also observed that a significant amount of cell death occurred within this domain and used cell ablation experiments to determine the ability of the embryo to compensate for cell loss.
为了研究果蝇胚胎原肠胚形成期头部背侧区域细胞的命运，我们使用光激活基因表达系统标记选定有丝分裂区域中的少量细胞。我们发现有丝分裂区域20，即位于背侧后表面的大约30个细胞的簇，产生头部的各种外胚层细胞类型，包括背袋上皮、视叶以及头部感觉器官，包括博尔威格氏器，即幼虫光感受器器官。我们发现视叶和幼虫光感受器起源于有丝分裂区域20中心附近的一些相邻细胞，这表明在有丝分裂区域内，存在一个指定幼虫视觉系统的子区域。除了幼虫视觉系统的组成部分外，有丝分裂区域20的这个中心区域还产生眼触角盘基板的一部分；产生成体视觉系统的细胞。我们还观察到在这个区域内发生了大量细胞死亡，并使用细胞消融实验来确定胚胎补偿细胞损失的能力。
