Cyclopamine (CyA) induces vp edge length reduction. Confocal projections of the Op in larvae treated with CyA. Images are lateral views with dorsal upwards and anterior towards the left. (A-C) Wild-type larvae treated with CyA (B) display a reduction in vp edge length and phenocopy ihha mutants (C). (D) Mutants treated with CyA look similar to untreated siblings. (E) Measurements of vj, jp and vp edge lengths for all four treatment categories. Lengths of vj and jp are not statistically different when compared between all possible combinations of treatments. Length of the vp edge is significantly reduced in CyA-treated wild-type larvae compared with wild-type controls, but is not significantly different from ihha mutants treated with CyA or ethanol. Data are presented as mean±s.d., **P<0.01 by Tukey-Kramer test, ne5 per treatment category. vp, edge connecting v and p; vj, edge connecting v and j; jp, edge connecting j and p. Scale bar: 50 μm.