Ectopic expression of the serine protease inhibitor PI9 modulates death receptor-mediated apoptosis.
Fiche publication
Date publication
août 2007
Auteurs
Membres identifiés du Cancéropôle Est :
Dr MICHEAU Olivier
Tous les auteurs :
Kummer JA, Micheau O, Schneider P, Bovenschen N, Broekhuizen R, Quadir R, Strik MC, Hack CE, Tschopp J
Lien Pubmed
Résumé
Apoptosis is a highly controlled process, whose triggering is associated with the activation of caspases. Apoptosis can be induced via a subgroup of the tumor necrosis factor (TNF) receptor superfamily, which recruit and activate pro-caspase-8 and -10. Regulation of apoptosis is achieved by several inhibitors, including c-FLICE-inhibitory protein, which prevents apoptosis by inhibiting the pro-apoptotic activation of upstream caspases. Here we show that the human intracellular serine protease inhibitor (serpin), protease inhibitor 9 (PI9), inhibits TNF-, TNF-related apoptosis-inducing ligand- and Fas ligand-mediated apoptosis in certain TNF-sensitive cell lines. The reactive center P1 residue of PI9 was required for this inhibition since PI9 harboring a Glu --> Ala mutation in its reactive center failed to impair death receptor-induced cell death. This suggests a classical serpin-protease interaction. Indeed, PI9 inhibited apoptotic death by directly interacting with the intermediate active forms of caspase-8 and -10. This indicates that PI9 can regulate pro-apoptotic apical caspases.
Référence
Cell Death Differ. 2007 Aug;14(8):1486-96