Tyrosine phosphorylation‐dependent activation of NF‐κB

• DOI: 10.1046/j.1432-1327.2001.02028.x
• Publication Date: 2003-03-11T18:25:13Z
• Authors: Antonia Livolsi; Valère Busuttil; Véronique Imbert; Robert T. Abraham; Jean‐François Peyron
• Keywords: Jurkat cells

Phosphorylation of the N‐terminal domain IκB inhibitory subunits induces activation transcription factor NF‐κB. Although serine phosphorylation has been shown to induce ubiquitination and subsequent proteasome‐mediated degradation IκB‐α, little is known about mechanisms that lead release active NF‐κB in T cells as a consequence tyrosine IκB‐α[Imbert, V., Rupec, R.A., Livolsi, A., Pahl, H.L., Traenckner, B.M., Mueller‐Dieckmann, C., Farahifar, D., Rossi, B., Auberger, P., Baeuerle, P. & Peyron, J.F. (1996) Cell 86 , 787–798]. The involvement kinases p56 lck ZAP‐70 this reaction demonstrated here using specific pharmacological inhibitors Jurkat mutants unable express these kinases. prevented both pervanadate‐induced IκB‐α on Tyr42 activation, we observed that, ‐deficient mutants, could still associate with despite Tyr42. Furthermore, SH2 appeared be required for but not phosphorylation. These results show are key components signaling pathway leads phosphotyrosine‐dependent confirm must control at least two different steps Finally, H 2 O which stimulates cells, an activator through IκB‐α.