ATR/Chk1 Pathway is Activated by Oxidative Stress in Response to UVA Light in Human Xeroderma Pigmentosum Variant Cells.
Photochem Photobiol
; 95(1): 345-354, 2019 01.
Article
em En
| MEDLINE
| ID: mdl-30362123
The crucial role of DNA polymerase eta in protecting against sunlight-induced tumors is evidenced in Xeroderma Pigmentosum Variant (XP-V) patients, who carry mutations in this protein and present increased frequency of skin cancer. XP-V cellular phenotypes may be aggravated if proteins of DNA damage response (DDR) pathway are blocked, as widely demonstrated by experiments with UVC light and caffeine. However, little is known about the participation of DDR in XP-V cells exposed to UVA light, the wavelengths patients are mostly exposed. Here, we demonstrate the participation of ATR kinase in protecting XP-V cells after receiving low UVA doses using a specific inhibitor, with a remarkable increase in sensitivity and γH2AX signaling. Corroborating ATR participation in UVA-DDR, a significant increase in Chk1 protein phosphorylation, as well as S-phase cell cycle arrest, is also observed. Moreover, the participation of oxidative stress is supported by the antioxidant action of N-acetylcysteine (NAC), which significantly protects XP-V cells from UVA light, even in the presence of the ATR inhibitor. These findings indicate that the ATR/Chk1 pathway is activated to control UVA-induced oxidatively generated DNA damage and emphasizes the role of ATR kinase as a mediator of genomic stability in pol eta defective cells.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Raios Ultravioleta
/
Xeroderma Pigmentoso
/
Estresse Oxidativo
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Proteínas Mutadas de Ataxia Telangiectasia
/
Quinase 1 do Ponto de Checagem
Limite:
Humans
Idioma:
En
Revista:
Photochem Photobiol
Ano de publicação:
2019
Tipo de documento:
Article
País de afiliação:
Brasil
País de publicação:
Estados Unidos