Fig. 4. Coexpression of a dominant negative version of DTcf (DTcf^DN), da or sc suppresses Wg-induced bristle inhibition. Scanning electron micrographs of adult fly heads (A,D,G,J,M) and pupal eyes (6 h APF) immunostained for Ac (B,E,H,K,N) or Da (C,F,I,L,O). (A-C) P[GMR-Gal4], P[UAS-lacZ]; (D-F) P[GMR-Gal4], P[UAS-wg], P[UAS-lacZ]; (G-I) P[GMR-Gal4], P[UAS-wg], P[UAS-TCF^DN]; (J-L) P[GMR-Gal4], P[UAS-wg], P[UAS-da]; (M-O) P[GMR-Gal4], P[UAS-wg], P[UAS-sc]. Ectopic expression of wg via the GMR promoter causes a severe reduction in eye size and completely blocks bristle formation (D). GMR/wg causes a huge decrease in Ac (E) and Da (F) expression. Co-expression of wg with TCF^DN partially suppresses the small eye and loss of bristles (G), as well as the Ac (H) and Da (I) inhibition. Co-expression of wg with da or sc does not significantly alter the small eye phenotype, but fully suppresses the bristle loss (J,M). GMR/wg/da causes a modest increase in Ac levels (K; compared with E). GMR/wg/sc also causes a modest increase in Ac (N) and Da (O) levels. All cultures were maintained at 25°C.