20(S)-hydroxy Cholesterol

20(S)-hydroxy Cholesterol is an allosteric agonist of the smoothened (Smo) receptor that activates the hedgehog (Hh) signaling pathway with an EC50 value of approxiately 3 ?M in a gene transcription reporter assay using NIH3T3 cells.{21991} 20(S)-hydroxy Cholesterol is necessary for normal Hh signaling. It induces Smo accumulation in primary cilia, an early event in signaling, and binds to the extracellular, cysteine-rich domain of Smo.{21991,40043} 20(S)-hydroxy Cholesterol also stimulates osteogenic differentiation of pluripotent bone marrow stromal cells, a process mediated via Hh and Notch signaling.{40041,18498,40042}