title: Systemic analysis of tyrosine phosphorylated proteins in angiopoietin-1 induced signaling pathway of endothelial cells.
abstract: Angiogenesis is an essential process in physiological and pathological processes and is well-regulated to maintain the cellular homeostasis by balancing the endothelial cells in proliferation and apoptosis. Angiopoietin-1 (Ang1) regulates angiogenesis as a ligand of Tie 2 receptor tyrosine kinase. However, the regulation pathways are not well-understood. To date, only a few of the signaling molecules involved in the Tie 2 receptor tyrosine kinase-mediated angiogenesis have been identified. In this study, we systematically identified tyrosine-phosphorylated proteins in Ang1-induced signaling cascade in human umbilical vein endothelial cells (HUVECs), employing proteomic analyses combining two-dimensional gel electrophoresis, Western analysis using phosphotyrosine antibody and mass spectrometry (MALDI-TOF MS and nanoLC-ESI-q-TOF tandem MS). We report here the identification, semiquantitative analysis, and kinetic changes of tyrosine-phosphorylated proteins in response to Ang1 in HUVECs and identified 66 proteins among 69 protein spots showing significant changes. Of these, p54nrb was validated as a molecule involved in cell migration. These results suggest that Ang1 induces stabilization of neo-vessel network by regulating the phosphorylations of metabolic and structural proteins.
authors.affiliation: Center for Cell Signaling & Drug Discovery Research, College of Pharmacy and Division of Life & Pharmaceutical Sciences, Ewha Womans University, Seoul 120-750, Korea.
authors.forename: Young Mee
authors.initials: YM
authors.lastname: Kim
authors.forename: Jawon
authors.initials: J
authors.lastname: Seo
authors.forename: Yung Hee
authors.initials: YH
authors.lastname: Kim
authors.forename: Jaeho
authors.initials: J
authors.lastname: Jeong
authors.forename: Hye Joon
authors.initials: HJ
authors.lastname: Joo
authors.forename: Dong-Hee
authors.initials: DH
authors.lastname: Lee
authors.forename: Gou Young
authors.initials: GY
authors.lastname: Koh
authors.forename: Kong-Joo
authors.initials: KJ
authors.lastname: Lee
mesh_terms: D042683:Angiopoietin-1 / Q000494:pharmacology*; D002465:Cell Movement; D002478:Cells, Cultured; D015180:Electrophoresis, Gel, Two-Dimensional / Q000379:methods; D042783:Endothelial Cells / Q000187:drug effects / Q000378:metabolism*; D004730:Endothelium, Vascular / Q000166:cytology / Q000378:metabolism; D006801:Humans; D010766:Phosphorylation; D020543:Proteome / Q000378:metabolism; D011994:Recombinant Proteins / Q000494:pharmacology; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods; D014443:Tyrosine / Q000378:metabolism*
chemical_list: D042683:Angiopoietin-1; D020543:Proteome; D011994:Recombinant Proteins; D014443:Tyrosine