Proteasome from cytokine-treated human cells shows stimulated BrAAP activity and depressed PGPH activity.
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.
Nelson
J E
JE
Department of Medicine, Mount Sinai School of Medicine, New York, NY 10029, USA. judith.nelson@mountsinai.org
Altschuller-Felberg
C
C
Loukissa
A
A
Cardozo
C
C
D000597:Amino Acids, Branched-Chain / Q000378:metabolism*; D002478:Cells, Cultured; D003374:Coumarins / Q000494:pharmacology; D003546:Cysteine Endopeptidases / Q000378:metabolism*; D010450:Endopeptidases / Q000378:metabolism*; D004730:Endothelium, Vascular / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D007371:Interferon-gamma / Q000494:pharmacology; D007375:Interleukin-1 / Q000494:pharmacology; D015850:Interleukin-6 / Q000494:pharmacology; D049934:Isocoumarins; D008070:Lipopolysaccharides / Q000494:pharmacology; D009097:Multienzyme Complexes / Q000378:metabolism*; D046988:Proteasome Endopeptidase Complex; D011506:Proteins / Q000378:metabolism; D015842:Serine Proteinase Inhibitors / Q000494:pharmacology; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology; D014471:Umbilical Veins / Q000166:cytology / Q000187:drug effects
D000597:Amino Acids, Branched-Chain; D003374:Coumarins; D007375:Interleukin-1; D015850:Interleukin-6; D049934:Isocoumarins; D008070:Lipopolysaccharides; D009097:Multienzyme Complexes; D011506:Proteins; D015842:Serine Proteinase Inhibitors; D014409:Tumor Necrosis Factor-alpha; C046235:3,4-dichloroisocoumarin; D007371:Interferon-gamma; D010450:Endopeptidases; D003546:Cysteine Endopeptidases; C077436:LMP7 protein; D046988:Proteasome Endopeptidase Complex; C114177:peptidylglutamylpeptide hydrolase