Skip to main content
Figure 1 | Breast Cancer Research

Figure 1

From: Key signaling nodes in mammary gland development and cancer: β-catenin

Figure 1

Canonical and noncanonical Wnt signaling pathways. In the absence of Wnt ligand (left panel), β-catenin is bound by a destruction complex within which Axin and adenomatous polyposis coli (APC) serve as scaffolds. Bound β-catenin is phosphorylated by glycogen synthase kinase-3β (GSK3β) and casein kinase 1 (CK1), then ubiquitinated by beta-transducing repeat-containing protein (β-TrCP) and targeted for proteasomal destruction. Binding of Wnt ligand (right panel) inhibits the destruction complex, allowing β-catenin to accumulate in the cytoplasm and translocate to the nucleus, where it binds Lef/T-cell factor (TCF) transcription factors and activates target genes. In addition, Wnt5a can activate noncanonical signaling pathways in cell-context-specific ways. DKK, Dickkopf; FRP, frizzled-related protein; Lgs, legless; LRP, low-density lipoprotein-related protein; Pygo2, pygopus homolog 2; WIF, Wnt inhibitory factor.

Back to article page