FIGURE 2.

CK2 stabilizes Smo and Ci and up-regulates Hh target gene expression. A, wild-type (WT) wing disc was stained with anti-En antibody. B, wing disc expressing UAS-CK2βRNAi by ptc-Gal4 was stained for En. C and C′, wing disc coexpressing UAS-CK2βRNAi with UAS-CK2β by ptc-Gal4 was stained for En (C) and FLAG (C′). White lines in A–C indicate the A/P boundaries that are defined by Ci staining (data not shown). D–F, wing discs coexpressing UAS-CK2βRNAi with UAS-GFP by ap-Gal4 were stained for Smo (D), Ci (D′), Ptc-lacZ (E), or En (F). GFP expression in D″ marks the RNAi cells. G and G′, wild-type wing imaginal disc was immunostained for endogenous Smo and Ci. H–K, wing discs from flies expressing UAS-FLAG-CK2α (H), UAS-FLAG-CK2β (I), UAS-FLAG-CK2αKM (J), or UAS-FLAG-CK2αKM plus UAS-CK2β (K) by MS1096 Gal4 were stained for Ci. L–L″, wing disc coexpressing UAS-FLAG-CK2α with UAS-CK2β by MS1096 Gal4 was stained for Ci, Smo, and dpp-lacZ. M–N′, wing discs coexpressing UAS-FLAG-CK2α with UAS-CK2β by act>CD2>Gal4 were stained for CD2 (green), Ci (red), Dpp-lacZ (blue), or Smo (gray). Clones were marked by the lack of CD2 staining (M) or by the elevation of Ci (N). Arrows in M′ and N indicate the stabilization of Ci, arrows in M″ indicate the elevated dpp-lacZ expression, and arrows in N′ indicate the accumulation of Smo in both A- and P-compartment cells that was induced by overexpressing CK2α with CK2β. All wing imaginal discs shown in this study were oriented with anterior on the left and ventral on the top.