Shh and Ptc are associated with taste bud maintenance in the adult mouse.

In mammals, taste receptor cells are organized into taste buds on tongue. Taste buds are trophically maintained by taste neurons and under continuous renewal, even in adults. We found that the receptor for Sonic hedgehog (Shh), Patched1 (Ptc), was expressed around taste buds where cells were proliferating, and that Shh was expressed within basal cells of taste buds. Denervation caused the loss of Shh and Ptc expression before the degeneration of taste buds.