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Fig. 9. Ectopic btd activity in wing induces spatially discriminated
expression of leg developmental markers. (A) Large btd-expressing
clone (blue) induces hth activity (green), but only on the periphery
(B), resembling the disposition of the normal leg disc. (C) Another
btd-expressing clone showing non-homogenous gain of Dll and dac
activity: all cells express Dll (red) but only about half gain
dac (green, D). (E) Another clone (arrow) showing a spatial
deployment of dac and Dll resembling closely that along the
PD axis in the normal leg (F): dac activity alone (green),
dac and Dll (yellow), and Dll only (red). In the
normal leg, these patterns of gene expression would correspond to the
positions of the femur, tibia and tarsus, respectively.