fig1

Figure 1. The off and on states of the Hedgehog (Hh) signaling pathway. Patched (Ptch) inhibits the activity of smoothened, which prevents the suppressor of fused-Gli1/2 complex from entering the nucleus and promotes Gli3 nuclear accumulation, leading to low expression of Hh target genes. Hh binding to Ptch activates the Hh signaling pathway by promoting Gli1/2 expression