Fig. 5. Differential regulation of dac by Dll along the PD axis of the antenna. Dac (red in all panels) expression expands distally in a Dll1/Dll3 hypomorphic antennal disc (A,A'). Dll protein (green in all panels) still is detected in these mutants. The overlap of Dll and Dac is yellow in all panels. In the antenna, the consequences to dac expression of loss of Dll vary with the PD position of the clone (B,B',C and C'). dac expression is activated non-cell autonomously (arrowheads in B') around a Dll-null clone (arrow in B,B') in a4. By contrast, dac expression is lost in a Dll-null clone in a3 (arrowhead in C,C').