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. Widely expressed, especially in the eye anlage, otic vesicle and developing somites. Minimal expression in oocytes and embryos prior to mid-blastula transition. Readily detected in the presomitic tissue from late gastrulae. By neurula stages, somitic expression is broader and also appears in developing neural structures and other anterior structures (eye anlage). By late neurula, the posterior expression is condensed into two stripes on each side, expression in the anterior tissues remains high in the developing eye. During tailbud stages, expression is still high in the eye vesicle, otic vesicle and other anterior regions, as well as the presomitic mesoderm. In the tadpole, highly expressed in the head, eye and otic vesicle, branchial arches and midportion of the somites. 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.