Fig. 2

Major signaling pathways affected by mutated FAT1. A Wnt/β-catenin signaling pathway: FAT1 can bind to β-catenin. Mutated FAT1 releases β-catenin from proteasomal degradation complex, which enhances the nuclear translocation and transcriptional activity of β-catenin. B Hippo/YAP1 activation and receptor tyrosine kinase (RTK) signaling pathways: Mutated FAT1 releases YAP1 from Hippo complex and activates it as a transcription factor. Mutated FAT1 also enhances HER3 activation and IRS1 expression, which may contribute to activation of multiple RTK signaling pathways. A potential link between YAP1 and ERBB signaling may be due to an autocrine loop through their ligand EGF and NRGs