Protein kinase C is involved in the early signals of interferon-alpha but not of interferon-gamma in U937 cells.
Increasing interest is being focused on the role of protein kinase C (PKC) in the mode of action of interferons (IFNs). Here we report that IFN-alpha induced a transient translocation of PKC from the cytosol to the particulate fraction of U937 cells. In contrast, after IFN-gamma treatment, no significant change in PKC activity could be observed. IFN-induced changes in membrane potential were also examined by means of a potential sensitive oxonal dye and flow cytometry. Hyperpolarization was induced by both IFN-alpha and IFN-gamma. The protein kinase inhibitor H-7 blocked the hyperpolarization induced by IFN-alpha but not by IFN-gamma. These concordant results suggest that PKC is involved in the early signals of IFN-alpha but not of IFN-gamma in U937 cells.
Csermely
P
P
Department of Pathology, Uniformed Services University, F. Edward Herbert School of Medicine, Bethesda, MD 20814.
Balint
E
E
Grimley
P M
PM
Aszalos
A
A
D019307:1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine; D002460:Cell Line; D006801:Humans; D007370:Interferon Type I / Q000502:physiology*; D007371:Interferon-gamma / Q000502:physiology; D007546:Isoquinolines / Q000494:pharmacology; D008564:Membrane Potentials / Q000187:drug effects; D010879:Piperazines / Q000494:pharmacology; D011493:Protein Kinase C / Q000502:physiology*; D047428:Protein Kinase Inhibitors; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology*
D007370:Interferon Type I; D007546:Isoquinolines; D010879:Piperazines; D047428:Protein Kinase Inhibitors; D007371:Interferon-gamma; D019307:1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine; D011493:Protein Kinase C