UVC-induced apoptosis in Dubca cells is independent of JNK activation and p53(Ser-15) phosphorylation.
Biochem Biophys Res Commun
; 383(4): 426-32, 2009 Jun 12.
Article
em En
| MEDLINE
| ID: mdl-19376088
ABSTRACT
Ultraviolet C (UVC) irradiation in mammalian cell lines activates a complex signaling network that leads to apoptosis. By using Dubca cells as a model system, we report the presence of a UVC-induced apoptotic pathway that is independent of c-Jun N-terminal kinases (JNKs) activation and p53 phosphorylation at Ser(15). Irradiation of Dubca cells with UVC results in a rapid JNK activation and phosphorylation of its downstream target c-Jun, as well as, phosphorylation of activating transcription factor 2 (ATF2). Pre-treatment with JNK inhibitor, SP600125, inhibited UVC-induced c-Jun phosphorylation without preventing UVC-induced apoptosis. Similarly, inhibition of UVC-induced p53 phosphorylation did not prevent Dubca cell apoptosis, suggesting that p53(Ser-15) phosphorylation is not associated with UVC-induced apoptosis signaling. The pan-caspase inhibitor z-VAD-fmk inhibited UVC-induced PARP cleavage, DNA fragmentation, and ultimately apoptosis of Dubca cells. Altogether, our study clearly indicates that UVC-induced apoptosis is independent of JNK and p53 activation in Dubca cells, rather, it is mediated through a caspase dependent pathway. Our findings are not in line with the ascribed critical role for JNKs activation, and downstream phosphorylation of targets such as c-Jun and ATF2 in UVC-induced apoptosis.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Serina
/
Raios Ultravioleta
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Proteína Supressora de Tumor p53
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Apoptose
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MAP Quinase Quinase 4
Tipo de estudo:
Prognostic_studies
Limite:
Animals
Idioma:
En
Revista:
Biochem Biophys Res Commun
Ano de publicação:
2009
Tipo de documento:
Article
País de afiliação:
Emirados Árabes Unidos