Selective role for beta-protein kinase C in signaling for O-2 generation but not degranulation or adherence in differentiated HL60 cells

J Biol Chem. 1998 Oct 16;273(42):27292-9. doi: 10.1074/jbc.273.42.27292.


A role for protein kinase C (PKC) isotypes is implicated in the activation of phagocytic cell functions. An antisense approach was used to selectively deplete beta-PKC, both betaI- and betaII-PKC, but not alpha-PKC, delta-PKC, or zeta-PKC in HL60 cells differentiated to a neutrophil-like phenotype (dHL60 cells). Depletion of beta-PKC in dHL60 cells elicited selective inhibition of O-2 generation triggered by fMet-Leu-Phe, immune complexes, or phorbol myristate acetate, an activator of PKC. In contrast, neither ligand-elicited beta-glucuronidase (azurophil granule) release nor adherence to fibronectin was inhibited by beta-PKC depletion. Ligand-induced phosphorylation of a subset of proteins was reduced in beta-PKC-depleted dHL60 cells. Phosphorylation of p47(phox) and translocation of p47(phox) to the membrane are essential for activation of the NADPH oxidase and generation of O-2. beta-PKC depletion had no effect on the level of p47(phox) in dHL60 cells but did significantly decrease ligand-induced phosphorylation of this protein. Furthermore, translocation of p47(phox) to the membrane in response to phorbol myristate acetate or fMet-Leu-Phe was reduced in beta-PKC-depleted cells. These results indicate that beta-PKC is essential for signaling for O-2 generation but not cell adherence or azurophil degranulation. Depletion of beta-PKC inhibited ligand-induced phosphorylation of p47(phox), translocation of p47(phox) to the membrane, and activation of O-2 generation.

Publication types

  • Comparative Study
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Biological Transport
  • Cell Adhesion
  • Cell Degranulation
  • Cell Differentiation
  • Fibronectins / metabolism
  • HL-60 Cells
  • Humans
  • Isoenzymes / genetics
  • Isoenzymes / metabolism*
  • Ligands
  • N-Formylmethionine Leucyl-Phenylalanine / pharmacology
  • NADPH Oxidases
  • Neutrophils / metabolism*
  • Oligonucleotides, Antisense
  • Phosphoproteins / metabolism
  • Phosphorylation
  • Protein Kinase C / genetics
  • Protein Kinase C / metabolism*
  • Protein Kinase C beta
  • Protein Kinase C-alpha
  • Protein Kinase C-delta
  • Reactive Oxygen Species / metabolism*
  • Signal Transduction
  • Superoxides / metabolism*
  • Tetradecanoylphorbol Acetate / pharmacology


  • Fibronectins
  • Isoenzymes
  • Ligands
  • Oligonucleotides, Antisense
  • Phosphoproteins
  • Reactive Oxygen Species
  • Superoxides
  • N-Formylmethionine Leucyl-Phenylalanine
  • NADPH Oxidases
  • neutrophil cytosolic factor 1
  • protein kinase C zeta
  • PRKCA protein, human
  • PRKCD protein, human
  • Protein Kinase C
  • Protein Kinase C beta
  • Protein Kinase C-alpha
  • Protein Kinase C-delta
  • Tetradecanoylphorbol Acetate