FIG. 6.

Differential responses of target sites to E(spl) and proneural proteins in vivo. The effects of misexpressing E(spl) (B, D, E, and F) and L’sc (H to J) proteins on expression of Gbe-B1-lacZ (B, D, H), Gbe-A1-lacZ (E, I), and Gbe-A2-lacZ (F, J). The patterns of Gal4 expression [and hence ectopic E(spl) and L’sc expression] are visualized by using UAS-LacZ (A, C, and D). Repression of Gbe-B1-lacZ by E(spl)Mβ (B) and E(spl)Mδ (D). LacZ expression from Gbe-A1-lacZ is also repressed by ectopic Mδ (E); however Gbe-A2-lacZ is insensitive to ectopic Mδ (F). Widespread expression of L’sc by using 765-Gal4 has no effect on Gbe-B1-lacZ expression but results in strong activation of Gbe-A1-lacZ and Gbe-A2-lacZ. Expression was detected by X-Gal staining for ∼16 h.