Fig. 3. sens and br-Z1, but not sc expression can by-pass repression of SOP formation in the wing margin by the unliganded EcR/USP complex. (A,A') Wing discs 0 hours APF with C96-GAL4 driving UAS-sc and UAS-GFP (A). sc misexpression does not by-pass EcR/USP repression. 22C10 expression (A') reveals only a slight advancement in sensory neuron differentiation. (B,B') Wing disc 0 hours APF with C96-GAL4 driving UAS-sens and UAS-GFP (B). 22C10 expression shows precocious differentiation of the sensory neurons (B'). (C,C') Control wing disc 2.5 hours APF with C96-GAL4 driving UAS-GFP. 22C10 is beginning to be expressed in the margin (C'). (D,D') Wing disc 2.5 hours APF with C96-GAL4 driving UAS-br-Z1 and UAS-GFP (D). Labeling with 22C10 shows the precociously differentiating neurons in the margin (D'). Note that their axons are projecting abnormally instead of following along the anterior margin. A differentiating sensory neuron is also seen in the posterior margin (arrow).