Maintenance of NF-kappa B activity is dependent on protein synthesis and the continuous presence of external stimuli.
The activation of NF-kappa B-like activities (called NF-kappa B) by tumor necrosis factor alpha (TNF alpha) and the phorbol ester phorbol 12-myristate 13-acetate (PMA) were compared. High levels of NF-kappa B activity were found 2 to 4 min after TNF alpha addition to human HL60 cells and lasted for at least 3 h, although the half-life of active NF-kappa B was less than 30 min. Inactive NF-kappa B, however, was relatively stable. NF-kappa B activation by TNF alpha was initially cycloheximide insensitive, but maintenance of NF-kappa B activity required ongoing protein synthesis and continuous stimulation by TNF alpha. Thus, the cells did not remain in an activated state without stimulation. In HL60 cells, NF-kappa B induction by PMA required 30 to 45 min and was completely dependent on de novo protein synthesis, while PMA (and interleukin-1) induced NF-kappa B activity rapidly in mouse 70Z/3 cells via a protein synthesis-independent mechanism. The NF-kappa B-like activities obtained under each condition behaved identically in methylation interference and native proteolytic fingerprinting assays. The NF-kappa B-like factors induced are thus all very similar or identical. We suggest that cell-specific differences in the protein kinase C-dependent activation of NF-kappa B may exist and that TNF alpha and PMA may induce expression of the gene(s) encoding NF-kappa B.
Hohmann
H P
HP
Central Research Units, F. Hoffmann-La Roche Ltd., Basel, Switzerland.
Remy
R
R
Scheidereit
C
C
van Loon
A P
AP
D000818:Animals; D001483:Base Sequence; D001665:Binding Sites; D003513:Cycloheximide / Q000494:pharmacology; D004268:DNA-Binding Proteins / Q000378:metabolism; D006801:Humans; D066298:In Vitro Techniques; D008745:Methylation; D051379:Mice; D008969:Molecular Sequence Data; D016328:NF-kappa B / Q000096:biosynthesis / Q000378:metabolism*; D010449:Peptide Mapping; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D013997:Time Factors; D014407:Tumor Cells, Cultured; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology
D004268:DNA-Binding Proteins; D016328:NF-kappa B; D014409:Tumor Necrosis Factor-alpha; D003513:Cycloheximide; D013755:Tetradecanoylphorbol Acetate