Fig. 7. Ptc14 does not internalize Hedgehog. (A,B) Ectopic wild type
PtcWTGFP (A) and Ptc14GFP (B) clones in the wing
imaginal disc stained with anti-Hh antibody (red). (a,b) Detail of the clones
shown in A and B. Only a few vesicles of Hh are observed in the clones
expressing the Ptc14 mutant protein (Ptc14GFP) (b)
compared with those that express the wild-type Ptc protein
(PtcWTGFP, arrows) (a). (C) Ptc (green) and Hh (red) expression in
a wing imaginal disc containing a ptc14 clone (labeled by
the absence of ß-gal staining, blue). Ptc staining inside the clone
(outlined in pale blue) has the same intensity levels than in the wild-type
area (arrow, green panel). (c,c') Magnification of the boxed areas in C.
Ptc and Hh colocalize in spots in the wild-type area (circles) (c). Ptc does
not accumulate in spots (green) in the ptc14 clone.
However, Hh vesicles are still present in the ptc14 clone
(red, arrowheads) (c'). (D) ptc14 clone at the AP
border (shown by the absence of green, GFP) in a shits1
wing disc after 3 hours at the restrictive temperature. In the absence of
dynamin-dependent internalization, Hh (red) accumulates in the
PtcWT territories at the AP border and also in the PtcWT
cells anterior to the mutant clone (arrowhead). However, Hh protein is not
accumulated in the ptc14 mutant cells (asterisk). Note
that the accumulation of Hh anterior to the ptc14 clone
(arrowhead) is higher than the accumulation in wild-type territory at the same
distance from the AP border (arrow). This indicates that Hh diffuses further
through the ptc14 mutant cells than through wild-type
cells. Scale bars: 50 µm.