» Articles » PMID: 8435068

A Protein Kinase Inhibitor, Staurosporine, Enhances the Expression of Phorbol Dibutyrate Binding Sites in Human Polymorphonuclear Leucocytes

Overview
Journal Biochem J
Specialty Biochemistry
Date 1993 Feb 1
PMID 8435068
Citations 3
Authors
Affiliations
Soon will be listed here.
Abstract

Staurosporine, a potent protein kinase C (PKC) inhibitor, was studied for its effects on the binding of phorbol 12,13-dibutyrate (PDBu) to human polymorphonuclear leucocytes (PMNs). Treatment of PMNs with staurosporine concentrations in the range 50 nM-2 microM at 37 degrees C (but not at 4 degrees C) and with 1 nM [3H]PDBu at both temperatures enhanced specific PDBu binding to PMNs by approx. 10-600% relative to control values. The potentiation was rapid (detectable within 1 min) and reached a plateau after 10 min of cell treatment. Scatchard analysis of the binding showed that staurosporine increased the total number of PDBu-binding sites (Bmax) from (178 +/- 9) x 10(3) (control) to (324 +/- 15) x 10(3) sites per PMN and lowered the apparent dissociation constant (Kd) from 9.6 +/- 0.8 (control) to 3.3 +/- 0.3 nM. In Ca(2+)-depleted cells, staurosporine induced similar changes in Kd values, whereas the Bmax. increased by 60%. Treatment of PMNs with 500 nM staurosporine enhanced PDBu binding in the particulate fraction by 120 +/- 7% and decreased PDBu binding in the soluble fraction by 69 +/- 4%, whereas PKC histone-phosphorylating activity of both fractions was almost completely inhibited. Incubation of staurosporine-pretreated particulate fractions with soluble fractions enriched the particulate fraction in PDBu-binding sites at the expense of the soluble fraction, without altering the binding affinity of PDBu for either fraction. Stimulation of PMNs with chemotactic N-formyl peptides induced a transient increase in PDBu binding. This effect was potentiated by approx. 52% by staurosporine. These results show that, in addition to its interference with PKC protein-phosphorylating activity, staurosporine enhances both PDBu-binding capacity and affinity to PMNs, through a mechanism involving Ca(2+)-dependent and -independent processes. Alterations of PDBu binding to soluble and particulate fractions suggest that the enhanced binding capacity in intact PMNs may be due to translocation of PDBu receptors, presumably PKC units. This phenomenon may affect PKC-dependent cellular responses mediated by physiological stimulation.

Citing Articles

NADPH oxidase-dependent reactive oxygen species mediate amplified TLR4 signaling and sepsis-induced mortality in Nrf2-deficient mice.

Kong X, Thimmulappa R, Kombairaju P, Biswal S J Immunol. 2010; 185(1):569-77.

PMID: 20511556 PMC: 2913313. DOI: 10.4049/jimmunol.0902315.


Stimulatory and suppressive signal transduction regulates vasoactive intestinal peptide receptor-1 (VPAC-1) in primary mouse CD4 T cells.

Vomhof-DeKrey E, Dorsam G Brain Behav Immun. 2008; 22(7):1024-1031.

PMID: 18555660 PMC: 2771589. DOI: 10.1016/j.bbi.2008.04.006.


Ca2+-controlled competitive diacylglycerol binding of protein kinase C isoenzymes in living cells.

Lenz J, Reusch H, Albrecht N, Schultz G, Schaefer M J Cell Biol. 2002; 159(2):291-302.

PMID: 12391024 PMC: 2173038. DOI: 10.1083/jcb.200203048.

References
1.
Ferrante A, Thong Y . Optimal conditions for simultaneous purification of mononuclear and polymorphonuclear leucocytes from human blood by the Hypaque-Ficoll method. J Immunol Methods. 1980; 36(2):109-17. DOI: 10.1016/0022-1759(80)90036-8. View

2.
Tischler A, Ruzicka L, Dobner P . A protein kinase inhibitor, staurosporine, mimics nerve growth factor induction of neurotensin/neuromedin N gene expression. J Biol Chem. 1991; 266(2):1141-6. View

3.
Kaibuchi K, Takai Y, NISHIZUKA Y . Cooperative roles of various membrane phospholipids in the activation of calcium-activated, phospholipid-dependent protein kinase. J Biol Chem. 1981; 256(14):7146-9. View

4.
Lehrer R, Cohen L . Receptor-mediated regulation of superoxide production in human neutrophils stimulated by phorbol myristate acetate. J Clin Invest. 1981; 68(5):1314-20. PMC: 370927. DOI: 10.1172/jci110378. View

5.
Castagna M, Takai Y, Kaibuchi K, Sano K, Kikkawa U, NISHIZUKA Y . Direct activation of calcium-activated, phospholipid-dependent protein kinase by tumor-promoting phorbol esters. J Biol Chem. 1982; 257(13):7847-51. View