Fig. 6. The JAK/STAT repression of wg in the disc epithelium is not mediated by known wg regulators. (A,B) A third instar eye disc carrying wg-lacZ in a wild-type background (A) or in a stat92E^85C9 Minute background (B). Heterozygous tissue (green), Dac (red), wg-lacZ (anti-ß-Gal, blue). Dac expression is lost in tissue that ectopically expresses wg (B). (C,D) A third instar eye disc carrying a wild-type (C) or a stat92E^85C9 M⁺ (D) chromosome. Heterozygous tissue (green), Hth (red), Elav (blue). Hth is expanded in both dorsal and ventral domains of stat92E^85C9 M⁺ eye discs (D, arrowheads). (E,F) A third instar eye disc carrying pnr>GFP in a wild-type (E) or a hop^M13/Y background (F). pnr>GFP (green) and Phalloidin (red). pnr is expanded posteriorly in the peripodial membrane of hop^M13 eye discs (F); increased pnr expression also evident in xz sections from the anterior (yellow box) and posterior (blue box) regions of the disc. (G,H) A late-third instar eye disc carrying pnr>GFP in a wild-type (G) or GMR-upd (H) background. pnr>GFP (green) and Phalloidin (red). Ectopic upd expression represses pnr to the region anterior to the furrow (H, arrow). (I) Model of JAK/STAT activity in Drosophila eye imaginal discs. fng, fringe; N^act, activated Notch receptors; Iro-C, Iroquois-C; A, apical; B, basal; D, dorsal; V, ventral; DP, disc proper; PM, peripodial membrane.