Receptor for Wnt proteins. Functions in the canonical Wnt/beta-catenin signaling pathway. The canonical Wnt/beta-catenin signaling pathway leads to the activation of disheveled proteins, inhibition of GSK-3 kinase, nuclear accumulation of beta-catenin and activation of Wnt target genes (By similarity). 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 (Probable). Expressed in the lens, otic placode (medial wall of the vesicle) and in epibranchial placode. Also expressed in the developing somites (dermomyotome). Somites and placodal expression appears at stage 9. At this stage, more obvious expression is detected in the neural tube (midbrain and rostral hindbrain), and persists through about stage 15. Strongly expressed in the ectoderm and around the otic placodes at stage 12. At stage 16, otic expression declines, expression in epibranchial placodes begins and peaks at stage 20. Expression in the lens of the eye is first seen at about stage 15, more evident at stage 16. At stage 17, seen in the ectoderm and mesenchyme of the limb primordia. Detected at stage 20 in the lip of the optic cup, in the mesenchyme surrounding the eye, in the ectoderm overlying the lens and in the ectoderm caudal and ventral of the olfactory placodes. From stages 20-30, expressed in cartilage and in the dermomyotomes and migrating sclerotomal cells forming vertebrae. 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.