Gómez-Skarmeta J L, Modolell J
Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Cientificas and Universidad Autónoma de Madrid, Spain.
Genes Dev. 1996 Nov 15;10(22):2935-45. doi: 10.1101/gad.10.22.2935.
The homeo box prepattern genes araucan (ara) and caupolican (caup) are coexpressed near the anterior-posterior (AP) compartment border of the developing Drosophila wing in two symmetrical patches located one at each side of the dorsoventral (DV) compartment border. ara-caup expression at these patches is necessary for the specification of the prospective vein L3 and associated sensory organs through the transcriptional activation, in smaller overlapping domains, of rhomboid/veinlet and the proneural genes achaete and scute. We show that ara-caup expression at those patches is mediated by the Hedgehog signal through its induction of high levels of Cubitus interruptus (Ci) protein in anterior cells near to the AP compartment border. The high levels of Ci activate decapentaplegic (dpp) expression, and, together, Ci and Dpp positively control ara-caup. The posterior border of the patches is apparently defined by repression by engrailed. Wingless accumulation at the DV border sets, also by repression, the gap between the two patches. Thus, ara and caup integrate the inputs of genes effecting the primary subdivisions of the wing disc into compartments to define two smaller territories. These in turn help create the even smaller domains of rhomboid/veinlet and achaete-scute expression.
同源异型框预模式基因阿劳坎（ara）和考波利坎（caup）在发育中的果蝇翅膀前后（AP）隔室边界附近共同表达，位于背腹（DV）隔室边界两侧的两个对称区域。在这些区域的ara - caup表达对于通过在较小的重叠区域中转录激活菱形/小静脉以及原神经基因achaete和scute来指定预期的L3静脉和相关感觉器官是必要的。我们表明，这些区域的ara - caup表达是由Hedgehog信号介导的，该信号通过在靠近AP隔室边界的前体细胞中诱导高水平的间断翅脉（Ci）蛋白来实现。高水平的Ci激活了果蝇转化生长因子β（dpp）的表达，并且Ci和Dpp共同正向调控ara - caup。这些区域的后边界显然是由engrailed的抑制作用所界定的。DV边界处的无翅蛋白积累同样通过抑制作用设定了两个区域之间的间隙。因此，ara和caup整合了影响翅盘主要细分到隔室中的基因输入，以定义两个较小的区域。这些区域进而有助于创建更小的菱形/小静脉以及achaete - scute表达区域。
