Halder G, Callaerts P, Gehring W J
Biozentrum, University of Basel, Switzerland.
Science. 1995 Mar 24;267(5205):1788-92. doi: 10.1126/science.7892602.
The Drosophila gene eyeless (ey) encodes a transcription factor with both a paired domain and a homeodomain. It is homologous to the mouse Small eye (Pax-6) gene and to the Aniridia gene in humans. These genes share extensive sequence identity, the position of three intron splice sites is conserved, and these genes are expressed similarly in the developing nervous system and in the eye during morphogenesis. Loss-of-function mutations in both the insect and in the mammalian genes have been shown to lead to a reduction or absence of eye structures, which suggests that ey functions in eye morphogenesis. By targeted expression of the ey complementary DNA in various imaginal disc primordia of Drosophila, ectopic eye structures were induced on the wings, the legs, and on the antennae. The ectopic eyes appeared morphologically normal and consisted of groups of fully differentiated ommatidia with a complete set of photoreceptor cells. These results support the proposition that ey is the master control gene for eye morphogenesis. Because homologous genes are present in vertebrates, ascidians, insects, cephalopods, and nemerteans, ey may function as a master control gene throughout the metazoa.
果蝇的无眼基因（ey）编码一种兼具配对结构域和同源结构域的转录因子。它与小鼠的小眼（Pax - 6）基因以及人类的无虹膜基因同源。这些基因具有广泛的序列同一性，三个内含子剪接位点的位置是保守的，并且这些基因在发育中的神经系统以及形态发生过程中的眼睛中表达相似。已证明昆虫和哺乳动物基因中的功能丧失突变会导致眼睛结构减少或缺失，这表明ey在眼睛形态发生中起作用。通过在果蝇的各种成虫盘原基中靶向表达ey互补DNA，在翅膀、腿部和触角上诱导出了异位眼结构。异位眼在形态上看起来正常，由具有完整感光细胞组的完全分化的小眼群组成。这些结果支持了ey是眼睛形态发生的主控基因这一观点。由于同源基因存在于脊椎动物、海鞘、昆虫、头足类动物和纽形动物中，ey可能在整个后生动物中作为主控基因发挥作用。
