Institute of Chemistry and Cell Biology, Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA. randy_king@hms.harvard.edu
Small-molecule antagonists of Hedgehog-pathway signaling, such as cyclopamine, have been known for some time. Now, small-molecule agonists of the Hedgehog pathway have also been identified. The finding that both antagonists and agonists target the protein Smoothened supports the emerging hypothesis that Smoothened may be regulated by endogenous small molecules.