Figure 7. Hh and Dpp are transported by cytonemes in the wing disc.
Depictions of transverse sections of the wing disc columnar epithelium showing that (upper drawing) basal cytonemes move Hh (blue) from the cells that make it in the posterior compartment to anterior compartment cells across the compartment border (dashed line) that activate Hh signal transduction and express Dpp (red). Dpp movement from the A/P signaling center is via apical cytonemes (lower drawing).