title: VEGF autoregulates its proliferative and migratory ERK1/2 and p38 cascades by enhancing the expression of DUSP1 and DUSP5 phosphatases in endothelial cells.
abstract: Vascular endothelial growth factor (VEGF) is a key angiogenic factor that regulates proliferation and migration of endothelial cells via phosphorylation of extracellular signal-regulated kinase-1/2 (ERK1/2) and p38, respectively. Here, we demonstrate that VEGF strongly induces the transcription of two dual-specificity phosphatase (DUSP) genes DUSP1 and DUSP5 in endothelial cells. Using fluorescence microscopy, fluorescence lifetime imaging (FLIM), and fluorescence cross-correlation spectroscopy (FCCS), we found that DUSP1/mitogen-activated protein kinases phosphatase-1 (MKP-1) was localized in both the nucleus and cytoplasm of endothelial cells, where it existed in complex with p38 (effective dissociation constant, K(D)(eff), values of 294 and 197 nM, respectively), whereas DUSP5 was localized in the nucleus of endothelial cells in complex with ERK1/2 (K(D)(eff) 345 nM). VEGF administration affected differentially the K(D)(eff) values of the DUSP1/p38 and DUSP5/ERK1/2 complexes. Gain-of-function and lack-of-function approaches revealed that DUSP1/MKP-1 dephosphorylates primarily VEGF-phosphorylated p38, thereby inhibiting endothelial cell migration, whereas DUSP5 dephosphorylates VEGF-phosphorylated ERK1/2 inhibiting proliferation of endothelial cells. Moreover, DUSP5 exhibited considerable nuclear anchoring activity on ERK1/2 in the nucleus, thereby diminishing ERK1/2 export to the cytoplasm decreasing its further availability for activation.
authors.affiliation: University of Ioannina, Greece.
authors.forename: Sofia
authors.initials: S
authors.lastname: Bellou
authors.forename: Mark A
authors.initials: MA
authors.lastname: Hink
authors.forename: Eleni
authors.initials: E
authors.lastname: Bagli
authors.forename: Ekaterini
authors.initials: E
authors.lastname: Panopoulou
authors.forename: Philippe I H
authors.initials: PI
authors.lastname: Bastiaens
authors.forename: Carol
authors.initials: C
authors.lastname: Murphy
authors.forename: Theodore
authors.initials: T
authors.lastname: Fotsis
mesh_terms: D002465:Cell Movement / Q000502:physiology; D002467:Cell Nucleus / Q000187:drug effects / Q000378:metabolism; D049109:Cell Proliferation; D002478:Cells, Cultured; D004347:Drug Interactions; D054638:Dual Specificity Phosphatase 1 / Q000235:genetics / Q000378:metabolism; D054637:Dual-Specificity Phosphatases / Q000235:genetics / Q000378:metabolism; D042783:Endothelial Cells / Q000166:cytology* / Q000201:enzymology*; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism*; D006706:Homeostasis; D006801:Humans; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3 / Q000378:metabolism; D054639:Mitogen-Activated Protein Kinase Phosphatases / Q000378:metabolism*; D010766:Phosphorylation; D014018:Tissue Distribution; D014158:Transcription, Genetic / Q000502:physiology; D014471:Umbilical Veins / Q000166:cytology; D015854:Up-Regulation / Q000502:physiology; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism* / Q000494:pharmacology; D048051:p38 Mitogen-Activated Protein Kinases / Q000378:metabolism
chemical_list: D042461:Vascular Endothelial Growth Factor A; D048049:Extracellular Signal-Regulated MAP Kinases; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D048051:p38 Mitogen-Activated Protein Kinases; D054639:Mitogen-Activated Protein Kinase Phosphatases; C517019:DUSP1 protein, human; C442320:DUSP5 protein, human; D054638:Dual Specificity Phosphatase 1; D054637:Dual-Specificity Phosphatases