Schmidt-Ott U, González-Gaitán M, Jäckle H, Technau G M
Abteilung Zellbiologie, Universität Mainz, Germany.
Proc Natl Acad Sci U S A. 1994 Aug 30;91(18):8363-7. doi: 10.1073/pnas.91.18.8363.
The development of the insect head tagma involves massive rearrangements and secondary fusions of segment anlagen during embryogenesis. Due to the lack of reliable morphological markers, the number, identity, and sequence of the head segments, particularly in the pregnathal region, are still a matter of ongoing debates. We examined the complex array of internal structures of the embryonic Drosophila melanogaster head such as the sensory structures and nerves of the peripheral and stomatogastric nervous systems, and we used embryonic head mutations causing a lack of overlapping segment anlagen to unravel the segmental identity and the sequence of the neural elements. Our results provide evidence for seven distinct segments in the Drosophila head, each characterized by a specific set of sensory neurons, consistent with the proposal that insects, myriapods, and crustaceans share a monophyletic evolutionary tree from a common annelid-like ancestor.
昆虫头部体节的发育在胚胎发生过程中涉及大量的重排和体节原基的二次融合。由于缺乏可靠的形态学标记，头部体节的数量、特征及顺序，尤其是在孕腹区，仍然是一个存在争议的问题。我们研究了黑腹果蝇胚胎头部内部结构的复杂阵列，如外周和口胃神经系统的感觉结构和神经，并且我们使用导致体节原基缺乏重叠的胚胎头部突变来阐明神经元件的体节特征和顺序。我们的结果为果蝇头部的七个不同体节提供了证据，每个体节都有一组特定的感觉神经元，这与昆虫、多足类和甲壳类从共同的类环节动物祖先共享一个单系进化树的观点一致。
