passages.id: split_4_validation_1206_passage
passages.type: progene_text
passages.text: We show that the S252W mutation allows the mesenchymal splice form of FGFR2 ( FGFR2c ) to bind and to be activated by the mesenchymally expressed ligands FGF7 or FGF10 and the epithelial splice form of FGFR2 ( FGFR2b ) to be activated by FGF2 , FGF6 , and FGF9 .