The Hh pathway modulates GB cell migration non-autonomously.

<p>(A,B) wt embryos stained with anti-Ptc and anti-Trh antibodies. Ptc protein is detected in vesicles in Ptc-expressing cells. (C,D) <i>ptclacZ</i> embryos stained with anti-ßgal and anti-Trh. Ptc expression is detected by nuclear ßgal presence. Scale bars are 50 μm in A and 10 μm in B–D. (E–H) Ventral views of stage 16 embryos stained with 2A12 to visualise the tracheal lumen. (I–I″) Dorsal, lateral and ventral views of the same stage 16 embryo expressing Hh in the VNC and stained with 2A12. Excess Hh in the VNC phenocopies the <i>ptc</i> mutant tracheal phenotype, but only on the ventral/lateral side of the embryo. (J–K) btl > tauGFP wt stage 15 embryo stained with anti-DSRF and GFP (J) and btlmoeGFP stage 15 embryos overexpressing Hh in the VNC and stained with anti-DSRF and GFP (K) or only DSRF (K′).