Receptor for Wnt proteins. Most of frizzled receptors are coupled to the beta-catenin canonical signaling pathway, which leads to the activation of disheveled proteins, inhibition of GSK-3 kinase, nuclear accumulation of beta-catenin and activation of Wnt target genes. A second signaling pathway involving PKC and calcium fluxes has been seen for some family members, but it is not yet clear if it represents a distinct pathway or if it can be integrated in the canonical pathway, as PKC seems to be required for Wnt-mediated inactivation of GSK-3 kinase. Both pathways seem to involve interactions with G-proteins. May be involved in transduction and intercellular transmission of polarity information during tissue morphogenesis and/or in differentiated tissues. Activated by Wnt8. Could have an antagonizing activity in the morphogenesis during development. Expressed in liver, lung, brain, testis, stomach, kidney, eye, skeletal muscle and skin. Expressed from blastula stage, peak expression at late gastrula stage. Expression localizes in neural fold at neurula stage; in the dorsal region of midbrain, hindbrain and spinal cord at tadpole stage. Lys-Thr-X-X-X-Trp motif interacts with the PDZ domain of Dvl (Disheveled) family members and is involved in the activation of the Wnt/beta-catenin signaling pathway. The FZ domain is involved in binding with Wnt ligands. Belongs to the G-protein coupled receptor Fz/Smo family.