UTP and ATP increase extracellular signal-regulated kinase 1/2 phosphorylation in bovine chromaffin cells through epidermal growth factor receptor transactivation.
Adenosine triphosphate (ATP) is coreleased with catecholamines from adrenal medullary chromaffin cells in response to sympathetic nervous system stimulation and may regulate these cells in an autocrine or paracrine manner. Increases in extracellular signal-regulated kinase (ERK) 1/2 phosphorylation were observed in response to ATP stimulation of bovine chromaffin cells. The signaling pathway involved in ATP-mediated ERK1/2 phosphorylation was investigated via Western blot analysis. ATP and uridine 5'-triphosphate (UTP) increased ERK1/2 phosphorylation potently, peaking between 5 and 15 min. The mitogen-activated protein kinase (MAPK/ERK)-activating kinase (MEK) inhibitor PD98059 blocked this response. UTP, which is selective for G-protein-coupled P2Y receptors, was the most potent agonist among several nucleotides tested. Adenosine 5'-O-(3-thio) triphosphate (ATPgammaS) and ATP were also potent agonists, characteristic of the P2Y(2) or P2Y(4) receptor subtypes, whereas agonists selective for P2X receptors or other P2Y receptor subtypes were weakly effective. The receptor involved was further characterized by the nonspecific P2 antagonists suramin and reactive blue 2, which each partially inhibited ATP-mediated ERK1/2 phosphorylation. Inhibitors of protein kinase C (PKC), protein kinase A (PKA), Ca(2+)/calmodulin-dependent protein kinase II (CaMKII), and phosphoinositide-3 kinase (PI3K) had no effect on ATP-mediated ERK1/2 phosphorylation. The Src inhibitor PP2, epidermal growth factor receptor (EGFR) inhibitor AG1478, and metalloproteinase inhibitor GM6001 decreased ATP-mediated ERK1/2 phosphorylation. These results suggest nucleotide-mediated ERK1/2 phosphorylation is mediated by a P2Y(2) or P2Y(4) receptor, which stimulates metalloproteinase-dependent transactivation of the EGFR.
Luke
Toni M
TM
University of Nebraska Medical Center, 985800 Nebraska Medical Center, Omaha, NE, 68198-5800, USA.
Hexum
Terry D
TD
J Cell Biol. 2001 Apr 30;153(3):491-501
11331301
Mol Pharmacol. 2004 Sep;66(3):601-11
15322252
Methods Enzymol. 1983;103:305-12
6321889
J Neurochem. 1995 Nov;65(5):2080-6
7595493
EMBO J. 1997 Dec 1;16(23):7032-44
9384582
Clin Med (Lond). 2002 Jan-Feb;2(1):45-53
11871639
Pharmacol Rev. 2006 Mar;58(1):58-86
16507883
J Biol Chem. 2000 May 5;275(18):13789-92
10788500
J Biol Chem. 1998 Sep 4;273(36):23110-7
9722539
Peptides. 2001 Mar;22(3):439-44
11287099
Nature. 1999 Dec 23-30;402(6764):884-8
10622253
Nature. 1996 Oct 10;383(6600):547-50
8849729
Fed Proc. 1983 Sep;42(12):2923-8
6136425
Cell Physiol Biochem. 2006;18(1-3):123-34
16914897
Brain Res. 2004 Dec 31;1030(2):183-92
15571668
J Biol Chem. 1998 Feb 20;273(8):4695-704
9468531
Biochem Biophys Res Commun. 1997 Oct 9;239(1):287-90
9345312
J Biol Chem. 1998 Jan 30;273(5):2653-60
9446569
Cell Signal. 2002 Aug;14(8):649-54
12020764
Mol Neurobiol. 2005;31(1-3):169-83
15953819
Eur J Pharmacol. 2004 Feb 6;485(1-3):137-40
14757133
FEBS Lett. 1999 Nov 19;461(3):273-6
10567710
J Biol Chem. 2000 Aug 18;275(33):25342-50
10840035
J Biol Chem. 2004 Feb 27;279(9):8212-8
14670955
J Biol Chem. 1996 Aug 9;271(32):19443-50
8702633
Nat Neurosci. 2005 Sep;8(9):1160-8
16116443