Fig. 4. Hh signaling is unaffected in dor mutant cells. (A) A confocal section of a Rab-7GFP/c765-Gal4 wing imaginal disc, stained with anti-Ptc (blue) and anti-Hh (red) antibodies. (a) Magnification of boxed area in A. The staining shows co-localization of Hh, Ptc and Rab-7 at the AP compartment border (circles in a). There are also spots of Ptc and Hh colocalization that do not colocalize with Rab7 (arrowheads in a); these are probably early endosomes. The inset in a shows detail of the co-localization of the three proteins at some of these spots. Rab-7 shows doughnut-shaped GFP emission (arrow) surrounding the Ptc and Hh spots (arrowheads). (B) dor⁸ mutant clones (labeled by the lack of ß-gal staining, blue) at the AP compartment border showing high accumulation of Hh (green) and Ptc (red) proteins because of the inhibition of lysosomal degradation. (C) Plot showing the green color pixel intensity of the cells in clone 1 (blue line) and clone 2 (red line) [corresponding to boxed areas in B (green panel)] with respect to the distance of the cells to the AP border. The same intensity (Hh accumulation) is seen in the A cells located at the same distance from the AP compartment border (arrowhead in B and C), whether Hh crosses (from the P compartment) a wild type (clone 1) or mutant (clone 2) area. (D) dor⁸ mutant clones (labeled by the lack of GFP staining, blue) close to the AP boundary showing no alteration in activation of the Hh targets [as shown by the expression of dpp-lacZ (red) (arrowhead) compared with its expression in the wild-type area (arrow)]. Scale bars: 50 µm in A,B,D; 15 µm in a.