Muscarinic receptor-stimulated cytosol-membrane translocation of RhoA.
Receptor-mediated phospholipase D activation in human embryonic kidney (HEK) cells stably expressing the m3 muscarinic acetylcholine receptor (mAChR) apparently involves the small G protein RhoA. Here, activation of RhoA was examined by measuring cytosol-membrane translocation, which is a sign of RhoA activation. RhoA translocation was induced by guanosine 5'-O-(3-thio)triphosphate in digitonin-permeabilized HEK cells, and in intact cells by the agonist-activated mAChR and by direct activation of heterotrimeric G proteins. RhoA translocation was also induced by the phosphotyrosine phosphatase inhibitor pervanadate, while the tyrosine kinase inhibitors tyrphostin 23 and genistein inhibited the mAChR-induced RhoA translocation. These data suggest that translocation and thus activation of RhoA by the G protein-coupled m3 mAChR in HEK cells apparently involves a tyrosine kinase-dependent reaction.
Keller
J
J
Institut für Pharmakologie, Universität GH Essen, Germany.
Schmidt
M
M
Hussein
B
B
Rümenapp
U
U
Jakobs
K H
KH
D001285:Atropine / Q000494:pharmacology; D001692:Biological Transport; D002217:Carbachol / Q000494:pharmacology; D002396:Catechols / Q000494:pharmacology; D002460:Cell Line; D002462:Cell Membrane / Q000378:metabolism; D002463:Cell Membrane Permeability; D003600:Cytosol / Q000378:metabolism; D004072:Digitonin / Q000494:pharmacology; D004791:Enzyme Inhibitors; D019204:GTP-Binding Proteins / Q000378:metabolism*; D019833:Genistein; D016244:Guanosine 5'-O-(3-Thiotriphosphate) / Q000494:pharmacology; D006801:Humans; D007529:Isoflavones / Q000494:pharmacology; D007668:Kidney / Q000166:cytology / Q000196:embryology; D018721:Muscarinic Agonists / Q000494:pharmacology; D018727:Muscarinic Antagonists / Q000494:pharmacology; D009570:Nitriles / Q000494:pharmacology; D017027:Protein Tyrosine Phosphatases / Q000037:antagonists & inhibitors; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors; D043587:Receptor, Muscarinic M3; D011976:Receptors, Muscarinic / Q000235:genetics / Q000502:physiology*; D020032:Tyrphostins; D014638:Vanadates / Q000494:pharmacology; D020742:rhoA GTP-Binding Protein
D002396:Catechols; D004791:Enzyme Inhibitors; D007529:Isoflavones; D018721:Muscarinic Agonists; D018727:Muscarinic Antagonists; D009570:Nitriles; D043587:Receptor, Muscarinic M3; D011976:Receptors, Muscarinic; D020032:Tyrphostins; C076715:pervanadate; D016244:Guanosine 5'-O-(3-Thiotriphosphate); D014638:Vanadates; D001285:Atropine; D002217:Carbachol; D019833:Genistein; D011505:Protein-Tyrosine Kinases; D017027:Protein Tyrosine Phosphatases; D019204:GTP-Binding Proteins; D020742:rhoA GTP-Binding Protein; D004072:Digitonin; C060641:tyrphostin A23