title: Integrin β3 crosstalk with VEGFR accommodating tyrosine phosphorylation as a regulatory switch.
abstract: Integrins mediate cell adhesion, migration, and survival by connecting intracellular machinery with the surrounding extracellular matrix. Previous studies demonstrated the importance of the interaction between β(3) integrin and VEGF type 2 receptor (VEGFR2) in VEGF-induced angiogenesis. Here we present in vitro evidence of the direct association between the cytoplasmic tails (CTs) of β(3) and VEGFR2. Specifically, the membrane-proximal motif around (801)YLSI in VEGFR2 mediates its binding to non-phosphorylated β(3)CT, accommodating an α-helical turn in integrin bound conformation. We also show that Y(747) phosphorylation of β(3) enhances the above interaction. To demonstrate the importance of β(3) phosphorylation in endothelial cell functions, we synthesized β(3)CT-mimicking Y(747) phosphorylated and unphosphorylated membrane permeable peptides. We show that a peptide containing phospho-Y(747) but not F(747) significantly inhibits VEGF-induced signaling and angiogenesis. Moreover, phospho-Y(747) peptide exhibits inhibitory effect only in WT but not in β(3) integrin knock-out or β(3) integrin knock-in cells expressing β(3) with two tyrosines substituted for phenylalanines, demonstrating its specificity. Importantly, these peptides have no effect on fibroblast growth factor receptor signaling. Collectively these data provide novel mechanistic insights into phosphorylation dependent cross-talk between integrin and VEGFR2.
authors.affiliation: Department of Molecular Cardiology, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, United States of America.
authors.forename: Xiaoxia Z
authors.initials: XZ
authors.lastname: West
authors.forename: Nahum
authors.initials: N
authors.lastname: Meller
authors.forename: Nikolay L
authors.initials: NL
authors.lastname: Malinin
authors.forename: Lalit
authors.initials: L
authors.lastname: Deshmukh
authors.forename: Julia
authors.initials: J
authors.lastname: Meller
authors.forename: Ganapati H
authors.initials: GH
authors.lastname: Mahabeleshwar
authors.forename: Malory E
authors.initials: ME
authors.lastname: Weber
authors.forename: Bethany A
authors.initials: BA
authors.lastname: Kerr
authors.forename: Olga
authors.initials: O
authors.lastname: Vinogradova
authors.forename: Tatiana V
authors.initials: TV
authors.lastname: Byzova
mesh_terms: D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D000818:Animals; D004789:Enzyme Activation / Q000187:drug effects; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism; D061307:Human Umbilical Vein Endothelial Cells / Q000187:drug effects / Q000201:enzymology; D006801:Humans; D066298:In Vitro Techniques; D039661:Integrin beta3 / Q000737:chemistry / Q000378:metabolism*; D009682:Magnetic Resonance Spectroscopy; D051379:Mice; D008810:Mice, Inbred C57BL; D008969:Molecular Sequence Data; D018919:Neovascularization, Physiologic; D010455:Peptides / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology; D010766:Phosphorylation / Q000187:drug effects; D019000:Phosphotyrosine / Q000378:metabolism*; D011485:Protein Binding / Q000187:drug effects; D020239:Receptor Cross-Talk / Q000187:drug effects; D015398:Signal Transduction / Q000187:drug effects; D042461:Vascular Endothelial Growth Factor A / Q000494:pharmacology; D040301:Vascular Endothelial Growth Factor Receptor-2 / Q000737:chemistry / Q000378:metabolism*
chemical_list: D039661:Integrin beta3; D010455:Peptides; D042461:Vascular Endothelial Growth Factor A; D019000:Phosphotyrosine; D040301:Vascular Endothelial Growth Factor Receptor-2; D048049:Extracellular Signal-Regulated MAP Kinases