The P2Y2 nucleotide receptor mediates vascular cell adhesion molecule-1 expression through interaction with VEGF receptor-2 (KDR/Flk-1)

J Biol Chem. 2004 Aug 20;279(34):35679-86. doi: 10.1074/jbc.M401799200. Epub 2004 Jun 2.

Abstract

UTP stimulates the expression of pro-inflammatory vascular cell adhesion molecule-1 (VCAM-1) in endothelial cells through activation of the P2Y(2) nucleotide receptor P2Y(2)R. Here, we demonstrated that activation of the P2Y(2)R induced rapid tyrosine phosphorylation of vascular endothelial growth factor receptor (VEGFR)-2 in human coronary artery endothelial cells (HCAEC). RNA interference targeting VEGFR-2 or inhibition of VEGFR-2 tyrosine kinase activity abolishes P2Y(2)R-mediated VCAM-1 expression. Furthermore, VEGFR-2 and the P2Y(2)R co-localize upon UTP stimulation. Deletion or mutation of two Src homology-3-binding sites in the C-terminal tail of the P2Y(2)R or inhibition of Src kinase activity abolished the P2Y(2)R-mediated transactivation of VEGFR-2 and subsequently inhibited UTP-induced VCAM-1 expression. Moreover, activation of VEGFR-2 by UTP leads to the phosphorylation of Vav2, a guanine nucleotide exchange factor for Rho family GTPases. Using a binding assay to measure the activity of the small GTPases Rho, we found that stimulation of HCAEC by UTP increased the activity of RhoA and Rac1 (but not Cdc42). Significantly, a dominant negative form of RhoA inhibited P2Y(2)R-mediated VCAM-1 expression, whereas expression of dominant negative forms of Cdc42 and Rac1 had no effect. These data indicate a novel mechanism whereby a nucleotide receptor transactivates a receptor tyrosine kinase to generate an inflammatory response associated with atherosclerosis.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Arteriosclerosis / etiology
  • Arteriosclerosis / metabolism
  • Binding Sites
  • Cell Line
  • Coronary Vessels / physiology
  • Endothelium, Vascular / physiology*
  • Humans
  • Molecular Sequence Data
  • Phosphorylation
  • Rabbits
  • Receptors, Purinergic P2 / chemistry
  • Receptors, Purinergic P2 / metabolism*
  • Receptors, Purinergic P2Y2
  • Signal Transduction / drug effects
  • Structure-Activity Relationship
  • Uridine Triphosphate / pharmacology
  • Vascular Cell Adhesion Molecule-1 / biosynthesis*
  • Vascular Endothelial Growth Factor Receptor-2 / agonists
  • Vascular Endothelial Growth Factor Receptor-2 / chemistry
  • Vascular Endothelial Growth Factor Receptor-2 / metabolism*

Substances

  • P2RY2 protein, human
  • Receptors, Purinergic P2
  • Receptors, Purinergic P2Y2
  • Vascular Cell Adhesion Molecule-1
  • Vascular Endothelial Growth Factor Receptor-2
  • Uridine Triphosphate