Baylies M K, Martinez Arias A, Bate M
Development. 1995 Nov;121(11):3829-37. doi: 10.1242/dev.121.11.3829.
The final pattern of the Drosophila larval body wall muscles depends critically on the prior segregation of muscle founder cells. We would like to understand the underlying molecular mechanisms which ensure the precise allocation and placement of these muscle founder cells. We have begun our analysis by examining the role of the segment polarity genes, known to be involved in the patterning of the ectoderm. Mutations in only one member of this class, wingless (wg), lead to the complete loss of a subset of muscle founder cells characterised by the expression of S59. Using the GAL4-targetted expression system, we find that Wingless, a secreted glycoprotein and well characterized signalling molecule, acts directly on the mesoderm to ensure the formation of S59-expressing founder cells. Moreover, we present evidence that Wg can signal across germ layers and that, in the wild-type embryo, Wg from the ectoderm could constitute an inductive signal for the initiation of the development of a subset of somatic muscles.
果蝇幼虫体壁肌肉的最终模式严重依赖于肌肉始祖细胞先前的分离。我们希望了解确保这些肌肉始祖细胞精确分配和定位的潜在分子机制。我们通过研究已知参与外胚层模式形成的节段极性基因的作用来开始我们的分析。仅这一类中的一个成员无翅（wg）发生突变，就会导致以S59表达为特征的一部分肌肉始祖细胞完全缺失。使用GAL4靶向表达系统，我们发现无翅蛋白，一种分泌型糖蛋白和特征明确的信号分子，直接作用于中胚层以确保表达S59的始祖细胞的形成。此外，我们提供的证据表明Wg可以跨胚层发出信号，并且在野生型胚胎中，来自外胚层的Wg可以构成启动一部分体壁肌肉发育的诱导信号。
