Fig. 3. Differential localization of Hh-GFP, HhN-GFP and Hhc85s-GFP in the plasma membrane. (A-C) Extracellular labeling of Hh-GFP (A), HhN-GFP (B) and Hhc85s-GFP (C) showing their distribution at the apical versus basolateral plane. (a-c) AP z sections of the same wing discs in A-C. (a') AP z sections of a wing disc double-stained with anti-Hh antibody (green) and anti-DE-cadherin (purple) as an apical region marker. The three Hh forms occur in the extracellular space on the apical side of the producing cells (asterisk), while only lipid-unmodified forms of Hh appear in the apical extracellular space in the A compartment (arrows in apical planes and Z sections). Wild-type Hh forms an extracellular gradient in the basolateral A cells next to the AP compartment, while the lipid-unmodified forms are poorly represented and do not form a gradient (arrowheads in basolateral panels and z sections).