Abstract
Bradykinin and phorbol 12-myristate 13-acetate stimulate adenylate cyclase activity in serum-depleted cultured airway smooth muscle via a protein kinase C (PKC)-dependent pathway. The probable target is the type II adenylate cyclase, which can integrate coincident signals from both PKC and Gs. Therefore, activation of Gs (by cholera-toxin pre-treatment) amplified the bradykinin-stimulated cyclic AMP signal and concurrently attenuated the partial activation of extracellular-signal-regulated kinase-2 (ERK-2) by bradykinin. We have previously demonstrated that, in order to induce full activation of ERK-2 with bradykinin, it is necessary to obliterate PKC-stimulated cyclic AMP formation. We concluded that the cyclic AMP signal limits the magnitude of ERK-2 activation [Pyne, Moughal, Stevens, Tolan and Pyne (1994) Biochem. J. 304, 611-616]. The present study indicates that the bradykinin-stimulated ERK-2 pathway is entirely cyclic AMP-sensitive, and suggests that coincident signal detection by adenylate cyclase may be an important physiological route for the modulation of early mitogenic signalling. Furthermore, the direct inhibition of adenylate cyclase activity enables bradykinin to induce DNA synthesis, indicating that the PKC-dependent activation of adenylate cyclase limits entry of cells into the cell cycle. These studies suggest that the mitogenicity of an agonist may be governed, in part, by its ability to stimulate an inhibitory cyclic AMP signal pathway in the cell. The activation of adenylate cyclase by PKC appears to be downstream of phospholipase D. However, in cells that were maintained in growth serum (i.e. were not growth-arrested), bradykinin was unable to elicit a PKC-stimulated cyclic AMP response. The lesion in the signal-response coupling was not at the level of either the receptor or phospholipase D, which remain functionally operative and suggests modification occurs at either PKC or adenylate cyclase itself. These studies are discussed with respect to the cell signal regulation of mitogenesis in airway smooth muscle.
Full text
PDF



Images in this article
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Boarder M. R. A role for phospholipase D in control of mitogenesis. Trends Pharmacol Sci. 1994 Feb;15(2):57–62. doi: 10.1016/0165-6147(94)90111-2. [DOI] [PubMed] [Google Scholar]
- Cook S. J., McCormick F. Inhibition by cAMP of Ras-dependent activation of Raf. Science. 1993 Nov 12;262(5136):1069–1072. doi: 10.1126/science.7694367. [DOI] [PubMed] [Google Scholar]
- Durieux M. E., Lynch K. R. Signalling properties of lysophosphatidic acid. Trends Pharmacol Sci. 1993 Jun;14(6):249–254. doi: 10.1016/0165-6147(93)90021-b. [DOI] [PubMed] [Google Scholar]
- Jacobowitz O., Iyengar R. Phorbol ester-induced stimulation and phosphorylation of adenylyl cyclase 2. Proc Natl Acad Sci U S A. 1994 Oct 25;91(22):10630–10634. doi: 10.1073/pnas.91.22.10630. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kolch W., Heidecker G., Kochs G., Hummel R., Vahidi H., Mischak H., Finkenzeller G., Marmé D., Rapp U. R. Protein kinase C alpha activates RAF-1 by direct phosphorylation. Nature. 1993 Jul 15;364(6434):249–252. doi: 10.1038/364249a0. [DOI] [PubMed] [Google Scholar]
- Lange-Carter C. A., Pleiman C. M., Gardner A. M., Blumer K. J., Johnson G. L. A divergence in the MAP kinase regulatory network defined by MEK kinase and Raf. Science. 1993 Apr 16;260(5106):315–319. doi: 10.1126/science.8385802. [DOI] [PubMed] [Google Scholar]
- McKenzie F. R., Seuwen K., Pouysségur J. Stimulation of phosphatidylcholine breakdown by thrombin and carbachol but not by tyrosine kinase receptor ligands in cells transfected with M1 muscarinic receptors. Rapid desensitization of phosphocholine-specific (PC) phospholipase D but sustained activity of PC-phospholipase C. J Biol Chem. 1992 Nov 15;267(32):22759–22769. [PubMed] [Google Scholar]
- Purkiss J. R., Boarder M. R. Stimulation of phosphatidate synthesis in endothelial cells in response to P2-receptor activation. Evidence for phospholipase C and phospholipase D involvement, phosphatidate and diacylglycerol interconversion and the role of protein kinase C. Biochem J. 1992 Oct 1;287(Pt 1):31–36. doi: 10.1042/bj2870031. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Pyne N. J., Freissmuth M., Pyne S. Phosphorylation of the recombinant spliced variants of the alpha-sub-unit of the stimulatory guanine-nucleotide binding regulatory protein (Gs) by the catalytic sub-unit of protein kinase A. Biochem Biophys Res Commun. 1992 Jul 31;186(2):1081–1086. doi: 10.1016/0006-291x(92)90857-h. [DOI] [PubMed] [Google Scholar]
- Pyne N. J., Moughal N., Stevens P. A., Tolan D., Pyne S. Protein kinase C-dependent cyclic AMP formation in airway smooth muscle: the role of type II adenylate cyclase and the blockade of extracellular-signal-regulated kinase-2 (ERK-2) activation. Biochem J. 1994 Dec 1;304(Pt 2):611–616. doi: 10.1042/bj3040611. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Pyne S., Pyne N. J. Bradykinin stimulates phospholipase D in primary cultures of guinea-pig tracheal smooth muscle. Biochem Pharmacol. 1993 Feb 9;45(3):593–603. doi: 10.1016/0006-2952(93)90132-g. [DOI] [PubMed] [Google Scholar]
- Pyne S., Pyne N. J. Bradykinin-stimulated phosphatidate and 1,2-diacylglycerol accumulation in guinea-pig airway smooth muscle: evidence for regulation 'down-stream' of phospholipases. Cell Signal. 1994 Mar;6(3):269–277. doi: 10.1016/0898-6568(94)90031-0. [DOI] [PubMed] [Google Scholar]
- Pyne S., Pyne N. J. Differential effects of B2 receptor antagonists upon bradykinin-stimulated phospholipase C and D in guinea-pig cultured tracheal smooth muscle. Br J Pharmacol. 1993 Sep;110(1):477–481. doi: 10.1111/j.1476-5381.1993.tb13835.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Rubin C. S., Erlichman J., Rosen O. M. Cyclic AMP-dependent protein kinase from bovine heart muscle. Methods Enzymol. 1974;38:308–315. doi: 10.1016/0076-6879(74)38047-0. [DOI] [PubMed] [Google Scholar]
- Stevens P. A., Pyne S., Grady M., Pyne N. J. Bradykinin-dependent activation of adenylate cyclase activity and cyclic AMP accumulation in tracheal smooth muscle occurs via protein kinase C-dependent and -independent pathways. Biochem J. 1994 Jan 1;297(Pt 1):233–239. doi: 10.1042/bj2970233. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Wu J., Dent P., Jelinek T., Wolfman A., Weber M. J., Sturgill T. W. Inhibition of the EGF-activated MAP kinase signaling pathway by adenosine 3',5'-monophosphate. Science. 1993 Nov 12;262(5136):1065–1069. doi: 10.1126/science.7694366. [DOI] [PubMed] [Google Scholar]

