Figure 10
From: Apigenin-induced lysosomal degradation of β-catenin in Wnt/β-catenin signaling
A model depicting the involvement of autophagy-lysosomal system in apigenin-induced degradation of β-catenin during Wnt signaling. In the presence of Wnt, Wnt ligand binds to its cognate receptor Frizzled and co-receptor LRP5/6. Dishevelled (DVL) moves from the cytoplasm to the plasma membrane and associates with Frizzled (step 1). Axin complex, including β-catenin and GSK3β, will also be translocated to the cell membrane and bind to phosphorylated LRP5/6 through Axin (step 2). β-catenin is stabilized and accumulated in the cytoplasm (step 3), and then enters the nucleus to associate with TCF/LEF and activates the expression of Wnt-responsive genes (step 4). Apigenin treatment suppresses the AKT/mTOR signaling pathway and induces the sequestration and degradation of β-catenin inside the lysosome (step 5), contributing to down-regulation of β-catenin during Wnt signaling.
