title: Fibroblast growth factor receptor-mediated rescue of x-ephrin B1-induced cell dissociation in Xenopus embryos.
abstract: The Eph family of receptor tyrosine kinases and their membrane-bound ligands, the ephrins, have been implicated in regulating cell adhesion and migration during development by mediating cell-to-cell signaling events. Genetic evidence suggests that ephrins may transduce signals and become tyrosine phosphorylated during embryogenesis. However, the induction and functional significance of ephrin phosphorylation is not yet clear. Here, we report that when we used ectopically expressed proteins, we found that an activated fibroblast growth factor (FGF) receptor associated with and induced the phosphorylation of ephrin B1 on tyrosine. Moreover, this phosphorylation reduced the ability of overexpressed ephrin B1 to reduce cell adhesion. In addition, we identified a region in the cytoplasmic tail of ephrin B1 that is critical for interaction with the FGF receptor; we also report FGF-induced phosphorylation of ephrins in a neural tissue. This is the first demonstration of communication between the FGF receptor family and the Eph ligand family and implicates cross talk between these two cell surface molecules in regulating cell adhesion.
authors.affiliation: Basic Research Laboratory, National Cancer Institute, Frederick, Maryland 21702, USA.
authors.forename: L D
authors.initials: LD
authors.lastname: Chong
authors.forename: E K
authors.initials: EK
authors.lastname: Park
authors.forename: E
authors.initials: E
authors.lastname: Latimer
authors.forename: R
authors.initials: R
authors.lastname: Friesel
authors.forename: I O
authors.initials: IO
authors.lastname: Daar
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites; D002448:Cell Adhesion / Q000187:drug effects; D002642:Chick Embryo; D017124:Conserved Sequence; D004625:Embryo, Nonmammalian / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism; D036387:Ephrin-B1; D005346:Fibroblast Growth Factors / Q000494:pharmacology; D015870:Gene Expression; D008565:Membrane Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D008969:Molecular Sequence Data; D009154:Mutation / Q000235:genetics; D010766:Phosphorylation / Q000187:drug effects; D019000:Phosphotyrosine / Q000378:metabolism; D011485:Protein Binding; D020239:Receptor Cross-Talk / Q000187:drug effects; D017468:Receptors, Fibroblast Growth Factor / Q000235:genetics / Q000378:metabolism*; D017479:Receptors, Platelet-Derived Growth Factor / Q000502:physiology; D012160:Retina / Q000187:drug effects / Q000196:embryology / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects; D014982:Xenopus laevis / Q000196:embryology
chemical_list: D036387:Ephrin-B1; D008565:Membrane Proteins; D017468:Receptors, Fibroblast Growth Factor; D019000:Phosphotyrosine; D005346:Fibroblast Growth Factors; D017479:Receptors, Platelet-Derived Growth Factor; D020928:Mitogen-Activated Protein Kinases