How Do Hedgehog Ligands Interact with Their Receptors?
Hedgehog ligands exert their effects by binding to a receptor called Patched (Ptch). In the absence of Hedgehog ligands, Ptch inhibits another protein called Smoothened (Smo). When Hedgehog ligands bind to Ptch, this inhibition is relieved, allowing Smo to activate the downstream signaling cascade. This leads to the activation of Gli transcription factors, which regulate the expression of target genes involved in cell proliferation, differentiation, and tissue patterning.
