A nuclear poly(ADP-ribose)-dependent signalosome confers DNA damage-induced IkappaB kinase activation.
Mol Cell
; 36(3): 365-78, 2009 Nov 13.
Article
em En
| MEDLINE
| ID: mdl-19917246
ABSTRACT
Upon genotoxic stresses, cells activate IkappaB kinases (IKKs) and the transcription factor NF-kappaB to modulate apoptotic responses. The SUMO-1 ligase PIASy and the kinase ataxia talengiectasia mutated (ATM) have been implicated to SUMOylate and phosphorylate nuclear IKKgamma (NEMO) in a consecutive mode of action, which in turn results in activation of cytoplasmic IKK holocomplexes. However, the nuclear signals and scaffold structures that initiate IKKgamma recruitment and activation are unknown. Here, we show that poly(ADP-ribose)-polymerase-1 (PARP-1) is the DNA proximal regulator, which senses DNA strand breaks and, through poly(ADP-ribose) (PAR) synthesis, assembles IKKgamma, PIASy, and ATM in a dynamic manner. Signalosome formation involves direct protein-protein interactions and binding to ADP-ribose polymers through PAR binding motifs (PARBM). Activated PARP-1 and a PARBM in PIASy are required to trigger IKKgamma SUMOylation, which in turn permits IKK and NF-kappaB activation, as well as NF-kappaB-regulated resistance to apoptosis.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Poli Adenosina Difosfato Ribose
/
Dano ao DNA
/
Transdução de Sinais
/
Quinase I-kappa B
Idioma:
En
Ano de publicação:
2009
Tipo de documento:
Article