Conventional protein kinase C isoenzymes undergo dephosphorylation in neutrophil-like HL-60 cells treated by chelerythrine or sanguinarine
Language English Country Switzerland Media print-electronic
Document type Journal Article, Research Support, Non-U.S. Gov't
- MeSH
- Alkaloids chemistry pharmacology MeSH
- Benzophenanthridines chemistry pharmacology MeSH
- Cell-Free System MeSH
- Cell Death drug effects MeSH
- Phosphorylation drug effects MeSH
- HL-60 Cells MeSH
- Isoquinolines chemistry pharmacology MeSH
- Isoenzymes metabolism MeSH
- Humans MeSH
- NADPH Oxidases metabolism MeSH
- Neutrophils cytology drug effects enzymology MeSH
- Protein Serine-Threonine Kinases metabolism MeSH
- Protein Kinase C metabolism MeSH
- 3-Phosphoinositide-Dependent Protein Kinases MeSH
- Respiratory Burst drug effects MeSH
- Substrate Specificity drug effects MeSH
- Protein Transport drug effects MeSH
- Dose-Response Relationship, Drug MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Names of Substances
- Alkaloids MeSH
- Benzophenanthridines MeSH
- chelerythrine MeSH Browser
- Isoquinolines MeSH
- Isoenzymes MeSH
- NADPH Oxidases MeSH
- PDPK1 protein, human MeSH Browser
- Protein Serine-Threonine Kinases MeSH
- Protein Kinase C MeSH
- 3-Phosphoinositide-Dependent Protein Kinases MeSH
- sanguinarine MeSH Browser
The quaternary benzo[c]phenanthridine alkaloid chelerythrine is widely used as an inhibitor of protein kinase C (PKC). However, in biological systems chelerythrine interacts with an array of proteins. In this study, we examined the effects of chelerythrine and sanguinarine on conventional PKCs (cPKCs) and PKC upstream kinase, phosphoinositide-dependent protein kinase 1 (PDK1), under complete inhibition conditions of PKC-dependent oxidative burst. In neutrophil-like HL-60 cells, sanguinarine and chelerythrine inhibited N-formyl-Met-Leu-Phe, phorbol 12-myristate 13-acetate (PMA)-, and A23187-induced oxidative burst with IC(50) values not exceeding 4.6 micromol/L, but the inhibition of PMA-stimulated cPKC activity in intact cells required at least fivefold higher alkaloid concentrations. At concentrations below 10 micromol/L, sanguinarine and chelerythrine prevented phosphorylation of approximately 80 kDa protein and sequestered approximately 60 kDa phosphoprotein in cytosol. Moreover, neither sanguinarine nor chelerythrine impaired PMA-stimulated translocation of autophosphorylated PKCalpha/betaII isoenzymes, but both alkaloids induced dephosphorylation of the turn motif in PKCalpha/betaII. The dephosphorylation did not occur in unstimulated cells and it was not accompanied by PKC degradation. Furthermore, cell treatment with sanguinarine or chelerythrine resulted in phosphorylation of approximately 70 kDa protein by PDK1. We conclude that PKC-dependent cellular events are affected by chelerythrine primarily by multiple protein interactions rather than by inhibition of PKC activity.
References provided by Crossref.org
12-O-Tetradecanoylphorbol-13-acetate increases cardiomyogenesis through PKC/ERK signaling