Differential potentiation of mitogen-stimulated phosphoinositide hydrolysis in protein kinase C-depleted Swiss 3T3 cells
- 1 September 1990
- journal article
- research article
- Published by Portland Press Ltd. in Biochemical Journal
- Vol. 270 (2) , 557-560
- https://doi.org/10.1042/bj2700557
Abstract
In Swiss 3T3 cells, depletion of protein kinase C (PKC) by prolonged incubation with phorbol esters protentiates the formation of total inositol phosphates in response to bombesin or vasopressin [Blakeley, Corps and Brown (1989) Biochem. J. 258, 177-185]. The characteristics of the accumulation of inositol phosphates in control and PKC-depleted cells stimulated by bombesin, vasopressin or prostaglandin F2a (PGF2a) have now been compared. The potentiation of the PGF2a response was greater than that of the vasopressin response which was, in turn, greater than that of the bombesin response. The time courses of the responses to all three agonists were biphasic, and both phases of the response were amplified in the PKC-depleted cells. These results provide further evidence for the involvement of a PKC-mediated negative-feedback loop regulating phosphoinositide hydrolysis in response to several 3T3 cell mitogens. The differential potentiation of the response to these agonists suggests that PKC might act at multiple sites within the signal transduction pathway.This publication has 28 references indexed in Scilit:
- The insulin receptor tyrosyl kinase phosphorylates holomeric forms of the guanine nucleotide regulatory proteins Gi and GoFEBS Letters, 1987
- Effects of bombesin and insulin on inositol (1,4,5) trisphosphate and inositol (1,3,4) trisphosphate formation in Swiss 3T3 cellsCell, 1986
- α‐Thrombin‐induced inositol phosphate formation in go‐arrested and cycling hamster lung fibroblasts: Evidence for a protein kinase C‐mediated desensitization responseJournal of Cellular Physiology, 1986
- Antibody probing of Western blots which have been stained with india inkAnalytical Biochemistry, 1986
- Phorbol ester inhibition of the hormone-stimulated phosphoinositide cycle in WRK-1 cellsBiochemical Journal, 1986
- PDGF-induced receptor phosphorylation and phosphoinositide hydrolysis are unaffected by protein kinase C activation in mouse Swiss 3T3 and human skin fibroblastsBiochemical and Biophysical Research Communications, 1986
- Protein kinase C phosphorylates the inhibitory guanine‐nucleotide‐binding regulatory component and apparently suppresses its function in hormonal inhibition of adenylate cyclaseEuropean Journal of Biochemistry, 1985
- Bidirectional control of cytosolic free calcium by thyrotropin-releasing hormone in pituitary cellsNature, 1985
- 1,2-Diacylglycerol and phorbol ester inhibit agonist-induced formation of inositol phosphates in human platelets: possible implications for negative feedback regulation of inositol phospholipid hydrolysis.Proceedings of the National Academy of Sciences, 1985
- Tumour‐promoting phorbol esters inhibit agonist‐induced phosphatidate formation and Ca2+ flux in human plateletsFEBS Letters, 1985