Vein Vein EGFR EGFR Rhomboid Casein Kinase 1 Patched Patched Smoothened Smoothened Cul3 Nedd8 Cubitus interruptus Cubitus interruptus Cubitus interruptus Fused Cubitus interruptus Proteasome Roc1a Nedd8 Cul1 Supernumerary limbs Costal-2 Supernumerary limbs GSK3 Casein Kinase 1 Suppressor of fused Cubitus interruptus Costal-2 Patched Patched Smoothened Smoothened Hedgehog Hedgehog Hedgehog Hedgehog Hedgehog Hedgehog Hedgehog Hedgehog Fused Cubitus interruptus Protein Kinase A Suppressor of fused