Diaz-Benjumea F J, Cohen B, Cohen S M
Differentiation Programme, European Molecular Biology Laboratory, Heidelberg, Germany.
Nature. 1994 Nov 10;372(6502):175-9. doi: 10.1038/372175a0.
The appendage primordia of Drosophila are subdivided into compartments by the localized expression of transcription factors. Interaction between cells in adjacent compartments establishes organizing centres responsible for generating spatial pattern and promoting cell proliferation in the developing appendages. Localized expression of hedgehog (hh) in the posterior compartment of the leg imaginal disc directs expression of wingless (wg) in ventral-anterior cells and decapentaplegic (dpp) in dorsal-anterior cells near the anterior-posterior compartment boundary; wg then acts to specify ventral cell fate and to organize the dorsal-ventral axis of the leg. Interaction between wg-expressing ventral cells and dorsal cells near the anterior-posterior compartment boundary promotes axis formation in the leg. Here we show that the combined action of wg-expressing cells in the ventral-anterior compartment and dpp-expressing cells in the dorsal-anterior compartment activates expression of Distal-less, a gene required for proximal-distal axis formation in the limbs. These results demonstrate that sequential interaction between anterior-posterior and dorsal-ventral compartments establishes the proximal-distal axis of the limbs.
果蝇的附肢原基通过转录因子的局部表达被细分为不同的区域。相邻区域的细胞间相互作用形成了组织中心，这些中心负责在发育中的附肢中产生空间模式并促进细胞增殖。腿部成虫盘后区中刺猬蛋白（hh）的局部表达引导腹侧前部细胞中无翅基因（wg）以及前后区边界附近背侧前部细胞中果蝇转化生长因子β（dpp）的表达；wg随后作用于确定腹侧细胞命运并组织腿部的背腹轴。前后区边界附近表达wg的腹侧细胞与背侧细胞之间的相互作用促进了腿部轴的形成。在此，我们表明腹侧前部区域中表达wg的细胞与背侧前部区域中表达dpp的细胞的联合作用激活了Distal-less的表达，Distal-less是肢体近端-远端轴形成所需的一个基因。这些结果表明，前后区与背腹区之间的顺序性相互作用建立了肢体的近端-远端轴。
