Role of the Wnt/β-Catenin Pathway in Renal Osteodystrophy

Figure 2

Wnt/β-catenin pathway and bone formation. On the left, no Wnt ligand is present and the phosphorylation complex, which consists of GSK3β, APC, CK1, and Axin, can freely phosphorylate β-catenin. This phosphorylation signals to an ubiquitin ligase that β-catenin has to be marked by degradation by the proteasome. On the right, a Wnt ligand binds to Frizzled (Fz) receptor and Lrp5/6 coreceptor. This causes Dvl to phosphorylate Lrp5/6, leading to the recruitment and subsequent inactivation of the phosphorylation complex. β-Catenin is free to translocate to the nucleus and act as a transcription factor for osteoblastic genes.