| First Author | Unnikrishnan A | Year | 2009 |
| Journal | Free Radic Biol Med | Volume | 46 |
| Issue | 11 | Pages | 1488-99 |
| PubMed ID | 19268524 | Mgi Jnum | J:148954 |
| Mgi Id | MGI:3847179 | Doi | 10.1016/j.freeradbiomed.2009.02.021 |
| Citation | Unnikrishnan A, et al. (2009) Oxidative stress alters base excision repair pathway and increases apoptotic response in apurinic/apyrimidinic endonuclease 1/redox factor-1 haploinsufficient mice. Free Radic Biol Med 46(11):1488-99 |
| abstractText | Apurinic/apyrimidinic endonuclease 1/redox factor-1 (APE1/Ref-1) is the redox regulator of multiple stress-inducible transcription factors, such as NF-kappaB, and the major 5'-endonuclease in base excision repair (BER). We utilized mice containing a heterozygous gene-targeted deletion of APE1/Ref-1 (Apex(+/-)) to determine the impact of APE1/Ref-1 haploinsufficiency on the processing of oxidative DNA damage induced by 2-nitropropane (2-NP) in the liver tissue of mice. APE1/Ref-1 haploinsufficiency results in a significant decline in NF-kappaB DNA-binding activity in response to oxidative stress in liver. In addition, loss of APE1/Ref-1 increases the apoptotic response to oxidative stress, in which significant increases in GADD45g expression, p53 protein stability, and caspase activity are observed. Oxidative stress displays a differential impact on monofunctional (UNG) and bifunctional (OGG1) DNA glycosylase-initiated BER in the liver of Apex(+/-) mice. APE1/Ref-1 haploinsufficiency results in a significant decline in the repair of oxidized bases (e.g., 8-OHdG), whereas removal of uracil is increased in liver nuclear extracts of mice using an in vitro BER assay. Apex(+/-) mice exposed to 2-NP displayed a significant decline in 3'-OH-containing single-strand breaks and an increase in aldehydic lesions in their liver DNA, suggesting an accumulation of repair intermediates of failed bifunctional DNA glycosylase-initiated BER. |
