title: Regulation of endocytosis, nuclear translocation, and signaling of fibroblast growth factor receptor 1 by E-cadherin.
abstract: Fibroblast growth factor (FGF) receptors (FGFRs) signal to modulate diverse cellular functions, including epithelial cell morphogenesis. In epithelial cells, E-cadherin plays a key role in cell-cell adhesion, and its function can be regulated through endocytic trafficking. In this study, we investigated the location, trafficking, and function of FGFR1 and E-cadherin and report a novel mechanism, based on endocytic trafficking, for the coregulation of E-cadherin and signaling from FGFR1. FGF induces the internalization of surface FGFR1 and surface E-cadherin, followed by nuclear translocation of FGFR1. The internalization of both proteins is regulated by common endocytic machinery, resulting in cointernalization of FGFR1 and E-cadherin into early endosomes. By blocking endocytosis, we show that this is a requisite, initial step for the nuclear translocation of FGFR1. Overexpression of E-cadherin blocks both the coendocytosis of E-cadherin and FGFR1, the nuclear translocation of FGFR1 and FGF-induced signaling to the mitogen-activated protein kinase pathway. Furthermore, stabilization of surface adhesive E-cadherin, by overexpressing p120ctn, also blocks internalization and nuclear translocation of FGFR1. These data reveal that conjoint endocytosis and trafficking is a novel mechanism for the coregulation of E-cadherin and FGFR1 during cell signaling and morphogenesis.
authors.affiliation: Institute for Molecular Bioscience, The University of Queensland, Brisbane, Australia 4072.
authors.forename: David M
authors.initials: DM
authors.lastname: Bryant
authors.forename: Fiona G
authors.initials: FG
authors.lastname: Wylie
authors.forename: Jennifer L
authors.initials: JL
authors.lastname: Stow
mesh_terms: D021581:Active Transport, Cell Nucleus; D015820:Cadherins / Q000378:metabolism*; D051177:Catenins; D002448:Cell Adhesion; D015815:Cell Adhesion Molecules / Q000378:metabolism; D045744:Cell Line, Tumor; D002467:Cell Nucleus / Q000378:metabolism; D018076:DNA, Complementary / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D004705:Endocytosis; D011992:Endosomes / Q000378:metabolism; D004847:Epithelial Cells / Q000378:metabolism; D006801:Humans; D015151:Immunoblotting; D020935:MAP Kinase Signaling System; D008856:Microscopy, Fluorescence; D010750:Phosphoproteins / Q000378:metabolism; D010957:Plasmids / Q000378:metabolism; D021381:Protein Transport; D020794:Receptor Protein-Tyrosine Kinases / Q000378:metabolism*; D051496:Receptor, Fibroblast Growth Factor, Type 1; D017468:Receptors, Fibroblast Growth Factor / Q000378:metabolism*; D015398:Signal Transduction; D013997:Time Factors; D014162:Transfection; D000095002:Delta Catenin
chemical_list: D015820:Cadherins; D051177:Catenins; D015815:Cell Adhesion Molecules; D018076:DNA, Complementary; D010750:Phosphoproteins; D017468:Receptors, Fibroblast Growth Factor; C496348:FGFR1 protein, human; D020794:Receptor Protein-Tyrosine Kinases; D051496:Receptor, Fibroblast Growth Factor, Type 1; D000095002:Delta Catenin; C000722347:CTNND1 protein, human