Stein D, Roth S, Vogelsang E, Nüsslein-Volhard C
Max-Planck-Institute für Entwicklungsbiologie, Tübingen, Federal Republic of Germany.
Cell. 1991 May 31;65(5):725-35. doi: 10.1016/0092-8674(91)90381-8.
Twelve maternal effect loci are required for the production of Drosophila embryos with a correct dorsoventral axis. Analysis of mosaic females indicates that the expression of the genes nudel, pipe, and windbeutel is required in the somatic tissue, presumably in the follicle cells that surround the oocyte. Thus, information coming from outside the egg cell influences dorsoventral pattern formation during embryogenesis. In transplantation experiments, the perivitelline fluid from the compartment surrounding the embryo can restore dorsoventral pattern to embryos from females mutant for nudel, pipe, or windbeutel. The positioning of the transplanted pervitelline fluid also determines the polarity of the restored dorsoventral axis. We propose that the polarizing activity, normally present at the ventral side of the egg, is a ligand for the Toll receptor. Presumably, local activation of the Toll protein by the ligand initiates the formation of the nuclear concentration gradient of the dorsal protein, thereby determining dorsoventral pattern.
要产生具有正确背腹轴的果蝇胚胎，需要12个母体效应基因座。对嵌合体雌性的分析表明，nudel、pipe和windbeutel基因的表达在体细胞组织中是必需的，推测是在围绕卵母细胞的卵泡细胞中。因此，来自卵细胞外部的信息会影响胚胎发育过程中的背腹模式形成。在移植实验中，来自胚胎周围区域的卵周液可以将背腹模式恢复到nudel、pipe或windbeutel突变雌性的胚胎中。移植的卵周液的位置也决定了恢复的背腹轴的极性。我们提出，通常存在于卵腹侧的极化活性是Toll受体的配体。推测，配体对Toll蛋白的局部激活会启动背蛋白核浓度梯度的形成，从而决定背腹模式。
