TRAF1 is a TNF inducible regulator of NF-kappaB activation.
Tumor necrosis factor receptor (TNFR)-associated factor TRAF1 was first identified as a component of the TNFR2 signalling complex. Unlike the other members of the TRAF family, TRAF1 lacks the N-terminal ring finger motif and has a tissue specific expression. Here we demonstrate that expression of TRAF1 is induced by TNF and the protein kinase C (PKC) activator PMA, but not by interleukin-1 (IL-1). TNF-induced upregulation of TRAF1 could be prevented by pretreatment of the cells with the proteasome inhibitor MG-132, whereas the PKC inhibitor Ro31-8220 was without effect. Interestingly, overexpression of TRAF1 in HEK293T completely prevented NF-kappaB activation induced by TNF, IL-1, or overexpression of TRAF2 or TRAF6. These data suggest that inducible expression of TRAF1 may serve a negative regulatory function in NF-kappaB signalling pathways.
Carpentier
I
I
Department of Molecular Biology, Flanders Interuniversity Institute for Biotechnology, University of Gent, K.L. Ledeganckstraat 35, B-9000, Gent, Belgium.
Beyaert
R
R
D004305:Dose-Response Relationship, Drug; D005786:Gene Expression Regulation; D017930:Genes, Reporter; D006367:HeLa Cells; D006801:Humans; D007375:Interleukin-1 / Q000378:metabolism; D015850:Interleukin-6 / Q000378:metabolism; D007700:Kinetics; D016328:NF-kappa B / Q000378:metabolism*; D010957:Plasmids; D011233:Precipitin Tests; D011506:Proteins / Q000378:metabolism / Q000502:physiology*; D015398:Signal Transduction; D047990:TNF Receptor-Associated Factor 1; D047992:TNF Receptor-Associated Factor 2; D013755:Tetradecanoylphorbol Acetate / Q000378:metabolism; D013997:Time Factors; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism*
D007375:Interleukin-1; D015850:Interleukin-6; D016328:NF-kappa B; D011506:Proteins; D047990:TNF Receptor-Associated Factor 1; D047992:TNF Receptor-Associated Factor 2; D014409:Tumor Necrosis Factor-alpha; D013755:Tetradecanoylphorbol Acetate