Frizzled; 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 inv [...]

Frizzled-3; 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 i [...]

Frizzled-4; 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 i [...]

Protein-serine O-palmitoleoyltransferase porcupine; Protein-serine O-palmitoleoyltransferase that acts as a key regulator of the Wnt signaling pathway by mediating the attachment of palmitoleate, a 16-carbon monounsaturated fatty acid (C16:1), to Wnt proteins. Serine palmitoleylation of Wnt proteins is required for efficient binding to frizzled receptors (By similarity). Also facilitates the glycosylation of Wnt family members, including wg and Wnt5. The cotranslational disulfide bond formation of wg competes with the N-glycosylation. Porc stimulates the post-translational N- glycosyla [...]

Frizzled-2; 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 i [...]

Protein shifted; Required for normal accumulation and movement of lipid- modified hedgehog (hh) morphogen. May act by stabilizing the interaction between heparan sulfate proteoglycans (HSPGs) and hh, HSPGs being required for diffusion of hh morphogen. Not involved in wingless (wg) morphogen movement, suggesting that it may provide HSPG specificity for Hh.

Palmitoleoyl-protein carboxylesterase NOTUM; Carboxylesterase that acts as a key negative regulator of the Wnt signaling pathway by specifically mediating depalmitoleoylation of WNT proteins. Serine palmitoleoylation of WNT proteins is required for efficient binding to frizzled receptors. Also acts as a regulator of long-range activity of Hedgehog (hh), possibly by regulating the switch between low and high level hh pathway signaling. Belongs to the pectinacetylesterase family. Notum subfamily.

Protein wntless; A segment polarity gene required for wingless (wg)-dependent patterning processes, acting in both wg-sending cells and wg-target cells. In non-neuronal cells wls directs wg secretion. The wls traffic loop encompasses the Golgi, the cell surface, an endocytic compartment and a retrograde route leading back to the Golgi, and involves clathrin-mediated endocytosis and the retromer complex (a conserved protein complex consisting of Vps35 and Vps26). In neuronal cells (the larval motorneuron NMJ), the wg signal moves across the synapse via the release of wls-containing exos [...]

Axin (Axn) encodes the key scaffolding protein for the canonical Wnt signalling pathway. In the absence of signal, it targets the product of arm for proteolysis inhibiting Wnt signalling. In the presence of signal, it forms a part of the membrane activation complex, disrupting the product of arm degradation. This pathway play roles in cell proliferation (imaginal disc), differentiation (embryonic patterning), death and stemness.