Vincent J P, Lawrence P A
Medical Research Council, Laboratory of Molecular Biology, Cambridge, England.
Cell. 1994 Jun 17;77(6):909-15. doi: 10.1016/0092-8674(94)90139-2.
The wingless protein is secreted, but it is not known whether it acts only on cells near to its site of synthesis or whether it has a longer range. Here, we use mosaic Drosophila embryos to estimate the range of wingless as it acts to maintain expression of the engrailed gene. We find that expression of engrailed is often sustained in those wingless- cells that are located near a wildtype patch of tissue, but this is not invariably so. Also, the numbers of cells maintaining engrailed expression are small. From these findings, we argue that wingless-expressing cells sustain engrailed expression only in adjoining cells. The wingless gene is also needed for maintenance of its own expression; using mosaics, we find that the range of this action is short as well.
无翅蛋白是分泌型的，但尚不清楚它是仅作用于其合成位点附近的细胞，还是具有更远的作用范围。在这里，我们使用镶嵌型果蝇胚胎来估计无翅蛋白在维持engrailed基因表达时的作用范围。我们发现，engrailed基因的表达在那些位于野生型组织斑块附近的无翅蛋白阴性细胞中常常得以维持，但并非总是如此。此外，维持engrailed基因表达的细胞数量很少。基于这些发现，我们认为表达无翅蛋白的细胞仅在相邻细胞中维持engrailed基因的表达。无翅基因对于维持其自身的表达也是必需的；通过镶嵌实验，我们发现这种作用的范围也很短。
