Biological responses of human apurinic endonuclease to radiation-induced DNA damage
- Emory Univ. School of Medicine, Atlanta, GA (United States)
Ionizing radiation produces a variety of DNA damage through active oxygen species such as the superoxide radical (O{sub 2}{sup -}), the hydroxyl radical (OH), and hydrogen peroxide (H{sub 2}O{sub 2}). Previous studies showed that human AP endonuclease, a counterpart of exonuclease III, can functionally replace E. coli exonuclease III to repair methyl methanesulfonate (MMS)-induced but not H{sub 2}O{sub 2}-induced DNA damage. Reduction of radiation-induced cytotoxicity by human AP endonuclease in a radiation-sensitive mutant of E. coli indicated that the AP site is one of the major forms of DNA damage produced by ionizing radiation. The removal of alkylation-induced AP sites and 3{prime}-blocking deoxyribose fragments by human AP endonuclease indicates that this enzyme is playing a pivotal role in the repair of oxidative DNA damage. In the current study, we examined the biological roles of AP endonuclease as being responsible for the repair of radiation-induced DNA damage in human cells.
- Research Organization:
- New York Academy of Sciences, New York, NY (United States)
- OSTI ID:
- 134861
- Report Number(s):
- CONF-9307221--
- Country of Publication:
- United States
- Language:
- English
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