| Wnt family of proteins are a large family of cysteine-rich secreted glycoproteins that regulate cell-cell interactions. They bind to members of the Frizzled family of 7 transmembrane receptors. Binding of Wnt to its receptors leads to activation of at least 3 distinct pathways: i) the canonical beta catenin pathway, ii) the planar cell polarity pathway, and, iii) the calcium pathway. In the canonical beta catenin pathway, binding of Wnt to its receptors leads to stabilization of beta catenin in the cytosol followed by its translocation into the nucleus where it activates the transcription factor Tcf/Lef leading to upregulation of target genes. The non canonical planar cell polarity pathway involves activation of Dishevelled, small G proteins (Rho/Rac) and JNK. The non canonical calcium pathway involves activation of calcium sensitive kinases, PKC and CAMKII by Dishevelled. The Wnt signaling pathway is similar to the Hedgehog pathway in many respects. Abnormalities in the Wnt signaling pathway are associated with a large variety of human malignancies including tumors of breast, colon, pancreas, liver and bone. |
| Pathway Statistics |
| Molecules Involved | 105 |
| Physical Interactions | 77 |
| Enzyme Catalysis | 27 |
| Transport | 11 |
| Genes Transcriptionally Regulated | 114 |
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