Repair of ionizing radiation DNA base damage in ataxia-telangiectasia cells
Micrococcus luteus endonuclease sensitive sites were measured by alkaline elution in normal human and ataxia-telangiectasia (AT) fibroblasts after ionizing radiation. Due to the sensitivity of this assay, repair of base damage after 3 to 6 kilorads has been measured after oxic or hypoxic radiation. With 5.5 kilorads of oxic radiation, more than 50% of the base damage was removed after 1.5 h of repair incubation in all cells, including exr+ and exr- AT cells, and approximately 75% was removed by 4 h. After 3 or 4.5 kilorads of hypoxic X-irradiation, repair was equivalent in normal and exr- AT cells. This study included three exr- AT strains which have been reported to be deficient in the removal of gamma-ray base damage at higher doses. Since these strains repaired ionizing radiation base damage normally at lower doses, which are more relevant to survival, it is concluded that the X-ray hypersensitivity of AT cells is probably not related to the repair of base damage.
- Research Organization:
- National Cancer Institute, Bethesda, MD
- OSTI ID:
- 5528936
- Journal Information:
- Cancer Res.; (United States), Journal Name: Cancer Res.; (United States)
- Country of Publication:
- United States
- Language:
- English
Similar Records
Repair of gamma-ray-induced DNA base damage in xeroderma pigmentosum cells
Ataxia-telangiectasia homo- and heterozygous cells show a normal repair and fixation response to anisotonic NaCl treatment after irradiation
Related Subjects
FIBROBLASTS
DNA REPAIR
RADIOSENSITIVITY
BIOLOGICAL PATHWAYS
DNA
ENDONUCLEASES
X RADIATION
ANIMAL CELLS
BIOLOGICAL RECOVERY
BIOLOGICAL REPAIR
CONNECTIVE TISSUE CELLS
DNA-ASE
ELECTROMAGNETIC RADIATION
ENZYMES
ESTERASES
HYDROLASES
IONIZING RADIATIONS
NUCLEIC ACIDS
ORGANIC COMPOUNDS
PHOSPHODIESTERASES
RADIATIONS
RECOVERY
REPAIR
SOMATIC CELLS
560121* - Radiation Effects on Cells- External Source- (-1987)