FIGURE 1.

Wnt/β-catenin signaling is off or on state. In steady-state, β-catenin is inactivated by a “destruction complex,” and phosphorylation, ubiquitinylated, and degraded of β-catenin is mediated by the protein complex. Wnt on state; Wnt molecules transmit the intracellular signal in the intracellular matrix through interacting with FZD receptors and LRP5/6. After that, the interaction triggers the intracellular signal cascade and promotes the accumulation of non-phosphorylated β-catenin, which translocates into the nucleus, and cooperates with TCF/LEF to trigger the transcription of Wnt target genes. Once Wnt ligands bind to co-receptors on cytomembrane, the combination of FZD and DVL could provide a recruitment platform for the β-catenin destruction. Wnt/β-catenin controls the expression of various downstream mediators implicated in renal fibrosis, such as Snail1, MMP-7, PAI-1, Twist, and FSP1.