Proteasome from cytokine-treated human cells shows stimulated BrAAP activity and depressed PGPH activity

Biochem Cell Biol. 2000;78(2):115-8.

Abstract

The branched chain amino acid-preferring (BrAAP) activity of multicatalytic proteinase complex isolated from human umbilical vein endothelial cells and treated with interferon-gamma was increased more than 2-fold, which was associated with a marked increase in LMP7 expression and decreased peptidylglutamyl peptide-hydrolyzing activity. Increases in BrAAP activity in supernatants from cells treated with interferon-gamma, tumor necrosis factor-alpha, interleukin-1 beta, interleukin-6, or lipopolysaccharide paralleled the increases in LMP7 expression. These findings are consistent with the conclusion that the increased BrAAP activity of LMP-containing multicatalytic proteinase complex results from incorporation of LMP7 or other LMP subunits.

MeSH terms

  • Amino Acids, Branched-Chain / metabolism*
  • Cells, Cultured
  • Coumarins / pharmacology
  • Cysteine Endopeptidases / metabolism*
  • Endopeptidases / metabolism*
  • Endothelium, Vascular / drug effects
  • Endothelium, Vascular / metabolism
  • Humans
  • Interferon-gamma / pharmacology
  • Interleukin-1 / pharmacology
  • Interleukin-6 / pharmacology
  • Isocoumarins
  • Lipopolysaccharides / pharmacology
  • Multienzyme Complexes / metabolism*
  • Proteasome Endopeptidase Complex
  • Proteins / metabolism
  • Serine Proteinase Inhibitors / pharmacology
  • Tumor Necrosis Factor-alpha / pharmacology
  • Umbilical Veins / cytology
  • Umbilical Veins / drug effects

Substances

  • Amino Acids, Branched-Chain
  • Coumarins
  • Interleukin-1
  • Interleukin-6
  • Isocoumarins
  • Lipopolysaccharides
  • Multienzyme Complexes
  • Proteins
  • Serine Proteinase Inhibitors
  • Tumor Necrosis Factor-alpha
  • 3,4-dichloroisocoumarin
  • Interferon-gamma
  • Endopeptidases
  • Cysteine Endopeptidases
  • LMP7 protein
  • Proteasome Endopeptidase Complex
  • peptidylglutamylpeptide hydrolase