Haynie J L, Bryant P J
J Exp Zool. 1986 Mar;237(3):293-308. doi: 10.1002/jez.1402370302.
We have studied the organization and development of the eye-antenna imaginal disc of Drosophila melanogaster. We examined the pattern of gynandromorph mosaicism and determined the "sturt distances" between 42 different structures of the head, antenna, and maxillary palpus. A morphogenetic map based on these sturt distances resembles more closely in size and shape that of a single thoracic segment than that of two or more adjacent segments, suggesting that the eye-antenna disc is derived from a single embryonic body segment. We examined the morphology of the eye-antenna discs in situ in late third-instar larvae in serial cross sections. The two discs are connected medially by a thin cellular membrane that probably serves to join the two discs during evagination and morphogenesis of the adult head. A fate map of the imaginal disc was established by cutting the mature disc into fragments and transplanting the fragments into host larvae for metamorphosis. The peripodial layer of the eye-antenna disc is thickened in several regions, and our data suggest that these thickened areas represent primordia of adult head structures. A comparison of the location of precursors in the imaginal disc with those of the differentiated structures of the adult head revealed the nature of the morphogenetic movements that must occur during evagination and differentiation.
我们研究了黑腹果蝇眼触角成虫盘的组织与发育。我们检查了雌雄嵌合体的镶嵌模式，并确定了头部、触角和下颚须42种不同结构之间的“斯特特距离”。基于这些斯特特距离构建的形态发生图谱在大小和形状上更类似于单个胸节，而非两个或更多相邻节段，这表明眼触角盘源自单个胚胎体节。我们在三龄晚期幼虫的连续横切面上原位检查了眼触角盘的形态。两个盘通过一层薄细胞膜在中间相连，这层膜可能在成虫头部外翻和形态发生过程中起到连接两个盘的作用。通过将成熟盘切成片段并将片段移植到宿主幼虫中进行变态，建立了成虫盘的命运图谱。眼触角盘的围蛹层在几个区域增厚，我们的数据表明这些增厚区域代表成虫头部结构的原基。将成虫盘中前体的位置与成虫头部分化结构的位置进行比较，揭示了外翻和分化过程中必然发生的形态发生运动的本质。
