Fig. 5. Widerborst polarizes independently of Dsh and Fmi and is needed for polarization of cortical domains. Arrows point distally. (A) Widerborst (green) and Coracle (red) in a dsh¹ pupal wing (aged 27 hours after puparium formation). Wdb is normally polarized. (B) Widerborst (green) and coracle (red) in a stan³ pupal wing (aged 27 hours after puparium formation). Wdb is normally polarized. (C) Frizzled, Flamingo, and Wdb staining in a pupal wing expressing Frizzled under the control of PatchedGAL4. Both Frizzled and Flamingo proteins were detected with mouse monoclonal antibodies and the red channel is a composite of their two patterns. In adjacent cells, Flamingo is repolarized perpendicular to the normal proximal-distal axis, but Wdb is normally polarized. (D) Flamingo and Frizzled, from the same image shown in C. (E) Wdb, from the same image shown in C. Fz-overexpressing cells are shaded red. (F) Wdb and Coracle, from the same image shown in C. (G-I) Wdb (G; red in H) and Fmi (I; green in H) in wings expressing dominant negative Wdb under the control of PatchedGAL4. Expression of dnWdb disrupts the polarization of wild-type Wdb up to five cells away from the overexpression domain. Fmi fails to polarize in dnWdb-expressing cells (H,I). Fmi also fails to polarize in cells near the dnWdb-expressing domain (asterisks in I). (J-L) Wdb (J; red in K) and Dsh (L; green in K) in wings expressing dominant negative Wdb under the control of PatchedGAL4. Expression of dnWdb disrupts the polarization of wild type Wdb in adjacent cells. Dsh fails to polarize in dnWdb-expressing cells (K,L). Dsh also fails to polarize in cells adjacent to the dnWdb-expressing domain (asterisks in L).