Patched (Ptc) is a conserved 12-pass transmembrane protein receptor that plays an obligate negative regulatory role in the Hedgehog signaling pathway in insects and vertebrates. Patched is an essential gene in embryogenesis that is important for proper segmentation in the fly embryo, mutations in which may be embryonic lethal. Patched functions as the receptor for the Hedgehog protein and controls its spatial distribution, in part via endocytosis of bound Hedgehog protein, which is then targeted for lysosomal degradation.