Role of Protein Kinase Cα in Signaling from the Histamine H1 Receptor to the Nucleus
- Institute of Cell Signalling and School of Biomedical Sciences, Medical School, Queen's Medical Centre, Nottingham, United Kingdom
Abstract
Stimulation of histamine H1 receptors produced a marked activation of inositol phospholipid hydrolysis, intracellular calcium mobilization, and stimulation of the c-fos promoter in CHO-H1 cells expressing the H1 receptor at a level of 3 pmol/mg protein. The latter response was determined using a luciferase-based reporter gene (pGL3). This response to histamine was not sensitive to inhibition by pertussis toxin but could be completely attenuated by the protein kinase C (PKC) inhibitor Ro-31-8220, or by 24-h pretreatment with the phorbol esters phorbol 12,13-dibutyrate or phorbol-12-myristate-13-acetate. Several isoforms of PKC can be detected in CHO-H1 cells (α, δ, ε, μ, ι, ζ) but only PKCα and PKCδ were down-regulated by prolonged treatment with phorbol esters. Of the two isoforms that were down-regulated, only protein kinase Cα was translocated to CHO-H1 cell membranes after stimulation with either histamine or phorbol esters. The PKC inhibitor Gö6976, which inhibits PKCα but not PKCδ, was also able to significantly attenuate the c-fos-luciferase response to histamine. The mitogen-activated protein kinase kinase inhibitor PD 98059 markedly inhibited the response to histamine, suggesting that the likely major target for PKCα was the mitogen-activated protein kinase pathway. These data suggest that the histamine H1 receptor can signal to the nucleus via PKCα after activation of phospholipase Cβ.
Footnotes
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Send reprint requests to: Professor S. J. Hill, Institute of Cell Signalling, Queen's Medical Centre, Nottingham, NG7 2UH, UK. E-mail:stephen.hill{at}nottingham.ac.uk
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This work was supported financially by the Medical Research Council and Wellcome Trust.
- Abbreviations:
- SRE
- serum response element
- CRE
- cAMP response element
- CHO
- Chinese hamster ovary
- PKC
- protein kinase C
- DMEM
- Dulbecco's modified Eagle's medium
- PDBu
- phorbol 12,13-dibutyrate
- PAGE
- polyacrylamide gel electrophoresis
- AM
- acetoxymethyl ester
- BAPTA
- 1,2-bis(2-aminophenoxy)ethane-N,N,N′,N′-tetraacetic acid
- IBD
- ingenol-3,20-dibenzoate
- PMA
- phorbol-12-myristate-13-acetate
- MAP
- mitogen-activated protein
- MEK
- mitogen-activated protein kinase kinase
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- Received September 13, 2000.
- Accepted January 11, 2001.
- The American Society for Pharmacology and Experimental Therapeutics
