EBR clonal analysis and Ft–Ds interaction. (A–C′) ft ^ΔE and ft^EBR1/2 cause a reduction of apical Ex, unlike ft^EBR1. XY confocal micrographs third instar wing imaginal discs containing ft^EBR1 (A and A′), ft^ΔE (B and B′), and ft^EBR1/2 (C and C′) mutant clones (marked by absence of RFP shown in red) with Ex staining (shown in gray). (D–I′)ft^ΔE and ft^EBR1/2 cause an increase of apical Dlish and Dachs, unlike ft^EBR1. XY confocal micrographs third instar wing imaginal discs containing ft^EBR1 (D, D′, G, and G′), ft^ΔE (E, E′, H, and H′) and ft^EBR1/2 (F, F′, I, and I′) mutant clones (marked by absence of RFP shown in red) with Dlish (D–F′) or Dachs (G–I′) staining (shown in gray). (J–K′) Loss of ds subtly increases Ex. XY confocal micrographs of the same third instar wing imaginal disc showing the pouch (J and J′) and the hinge (K and K′) containing ds^38K mutant clones (marked by absence of RFP shown in red) with Ex staining (shown in gray). All XY images are orientated as dorsal up. Clonal boundaries are marked by yellow dotted lines. Scale bars are 10 µm. (L) Ft^ΔECD interacts with Ds^ICD. S2R⁺ cell expression and IP of FLAG-tagged Ds^ICD in the presence of Ft^ΔECD, compared to FLAG-bead controls. Ft presents as multiple bands due to proteolytic processing (Feng and Irvine, 2009; Sopko et al., 2009). (M) Ft^ICD directly binds Ds^ICD. In vitro transcribed and translated Ds^ICD was incubated with bacterially expressed and purified GST alone or GST::Ft^ICD and subjected to GST-purification. The expression and presence of proteins was analyzed by immunoblotting with the indicated antibodies. WB, Western blot. Source data are available for this figure: SourceData F5.