Figure 2. EGFR signaling modulates Cic-mediated repression of mirr. (A and B) Lateral views of stage-10 wild-type (A and A’) and cicΔC2 (B and B’) egg chambers carrying the mirrP2 (mirr-lacZ; ref. 33) enhancer trap. Double stainings with anti-β-galactosidase (A and B, green) and DAPI (A’ and B’, blue) are shown. (C and D) Dorsal views of stage-10 mosaic egg chambers expressing Cic (C and C’) and CicΔC2 (D and D’) proteins in clones marked by expression of GFP (C and D, green). (C’ and D’) show anti-β-galactosidase stainings of mirr-lacZ expression (red). Only CicΔC2 causes full repression of mirr-lacZ. (E and F) Lateral views of stage-10 wild-type (E and E’) and cicΔC2 (F and F’) egg chambers carrying the M2-lacZ (pipe-lacZ; ref. 12) reporter. Stainings with anti-β-galactosidase and anti-Gurken antibodies (E and F, green) and DAPI (E’ and F’, blue) are shown; the Gurken signals are indicated with asterisks. A single genomic cicΔC2 transgene (see ref. 22) leads to expanded pipe-lacZ expression by an average of 1.3 cells (n = 20) in the dorsal-posterior region (arrowhead in panel F). (G and H) Lateral views of stage-10 mosaic egg chambers expressing Cic (G and G’) and CicΔC2 (H and H’) proteins in clones marked by expression of GFP (G and H, green). G’ and H’ show anti-β-galactosidase stainings of M1-lacZ (pipe-lacZ; ref. 12) expression (red). Note that Cic-expressing clones show partial derepression of pipe-lacZ close to the endogenous pipe domain (arrowheads, G’), whereas CicΔC2 causes robust derepression of the reporter in all positions.