title: Divergent roles of prokineticin receptors in the endothelial cells: angiogenesis and fenestration.
abstract: Prokineticins are secreted peptides that activate two G protein-coupled receptors: PKR1 and PKR2. Prokineticins induce angiogenesis and fenestration, but the cognate receptors involved in these functions are unknown. We hypothesized a role for prokineticin receptor signaling pathways and expression profiles in determining the selective effects of prokineticins on coronary endothelial cells (H5V). Activation of the PKR1/MAPK/Akt signaling pathway stimulates proliferation, migration, and angiogenesis in H5V cells, in which PKR1 predominates over PKR2. PKR1 was colocalized with Galpha(11) and was internalized following the stimulation of these cells with prokineticin-2. Knock down of PKR1 or Galpha(11) expression in H5V cells effectively inhibited prokineticin-2-induced vessel formation and MAPK/Akt activation, indicating a role for PKR1/Galpha(11) in this process. However, in conditions in which PKR2 predominated over PKR1, these cells displayed a fenestrated endothelial cell phenotype. H5V cells overexpressing PKR2 displayed large numbers of multivesicular bodies and caveolar clusters and a disruption of the distribution of zonula occluden-1 tight junction protein. Prokineticin-2 induced the colocalization of PKR2 with Galpha(12), and activated Galpha(12), which bound to zonula occluden-1 to trigger the degradation of this protein in these cells. Prokineticin-2 induced the formation of vessel-like structures by human aortic endothelial cells expressing only PKR1, and disorganized the tight junctions in human hepatic sinusoidal endothelial cells expressing only PKR2, confirming the divergent roles of these receptors. Our findings show the functional characteristics of coronary endothelial cells depend on the expression of PKR1 and PKR2 levels and the divergent signaling pathways used by these receptors.
authors.affiliation: Institut de Recherche de l'Ecole de Biotechnologie de Strasbourg, Centre National de la Recherche Scientifique, Université de Strasbourg, Illkirch, France.
authors.forename: Célia
authors.initials: C
authors.lastname: Guilini
authors.forename: Kyoji
authors.initials: K
authors.lastname: Urayama
authors.forename: Gulen
authors.initials: G
authors.lastname: Turkeri
authors.forename: Deniz B
authors.initials: DB
authors.lastname: Dedeoglu
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Kurose
authors.forename: Nadia
authors.initials: N
authors.lastname: Messaddeq
authors.forename: Canan G
authors.initials: CG
authors.lastname: Nebigil
mesh_terms: D000818:Animals; D002460:Cell Line; D002465:Cell Movement; D049109:Cell Proliferation; D002478:Cells, Cultured; D004730:Endothelium, Vascular / Q000166:cytology / Q000502:physiology*; D043802:GTP-Binding Protein alpha Subunits, Gq-G11 / Q000378:metabolism; D006801:Humans; D008565:Membrane Proteins / Q000378:metabolism; D051379:Mice; D020929:Mitogen-Activated Protein Kinase Kinases / Q000502:physiology; D023421:Models, Animal; D018919:Neovascularization, Physiologic / Q000502:physiology*; D010750:Phosphoproteins / Q000378:metabolism; D051057:Proto-Oncogene Proteins c-akt / Q000502:physiology; D043562:Receptors, G-Protein-Coupled / Q000235:genetics / Q000502:physiology*; D018000:Receptors, Peptide / Q000235:genetics / Q000502:physiology*; D015398:Signal Transduction / Q000502:physiology; D062826:Zonula Occludens-1 Protein
chemical_list: D008565:Membrane Proteins; C525015:PKR1 protein, mouse; C525016:PKR2 protein, mouse; C470837:PROKR1 protein, human; C470838:PROKR2 protein, human; D010750:Phosphoproteins; D043562:Receptors, G-Protein-Coupled; D018000:Receptors, Peptide; C569042:TJP1 protein, human; C569043:Tjp1 protein, mouse; D062826:Zonula Occludens-1 Protein; D051057:Proto-Oncogene Proteins c-akt; D020929:Mitogen-Activated Protein Kinase Kinases; D043802:GTP-Binding Protein alpha Subunits, Gq-G11