Rothbächer U, Laurent M N, Blitz I L, Watabe T, Marsh J L, Cho K W
Department of Developmental and Cell Biology, University of California, Irvine 92717-2300, USA.
Dev Biol. 1995 Aug;170(2):717-21. doi: 10.1006/dbio.1995.1249.
Wnt genes encode secreted growth factors that exhibit potent effects on both embryonic and postembryonic development in vertebrates and invertebrates. Recently, the dishevelled (dsh), shaggy/zeste-white 3, and armadillo genes have been shown to participate in Wnt (wingless; wg) signaling in Drosophila. Vertebrate genes that have sequence similarities to all of these Drosophila genes have been identified. To determine whether these structurally conserved components of insect wg signaling represent a functionally conserved Wnt signaling pathway in vertebrates, we investigated the role of Drosophila dsh in Xenopus Wnt signaling. Xenopus embryos ectopically injected with Drosophila dsh mRNA developed duplicated axes similar to those seen in embryos injected with Wnt mRNAs. The involvement of dsh function in the Wnt signaling pathway in Xenopus was demonstrated using two assays which are specifically sensitive to Wnt signaling: synergistic induction of dorsal mesoderm with bFGF and the specific induction of a Wnt-responsive reporter gene. These findings support the notion that the intracellular response to the Wnt signal has been conserved during evolution to such an extent that its components may be interchanged between distantly related species.
Wnt基因编码分泌型生长因子，对脊椎动物和无脊椎动物的胚胎发育及胚后发育均具有显著影响。最近研究表明，在果蝇中，蓬乱蛋白（dsh）、蓬乱/小体白色3基因以及犰狳基因参与Wnt（无翅基因；wg）信号传导。已鉴定出与所有这些果蝇基因具有序列相似性的脊椎动物基因。为了确定昆虫wg信号传导中这些结构保守的成分在脊椎动物中是否代表功能保守的Wnt信号通路，我们研究了果蝇dsh在非洲爪蟾Wnt信号传导中的作用。异位注射果蝇dsh mRNA的非洲爪蟾胚胎发育出了与注射Wnt mRNA的胚胎相似的重复轴。利用对Wnt信号特别敏感的两种检测方法，证明了dsh功能在非洲爪蟾Wnt信号通路中的参与：bFGF协同诱导背侧中胚层以及Wnt反应性报告基因的特异性诱导。这些发现支持了这样一种观点，即Wnt信号的细胞内反应在进化过程中得到了高度保守，以至于其成分可以在远缘物种之间互换。
