Detection of DNA single-strand breaks during the repair of UV damage in xeroderma pigmentosum cells
In this investigation, xeroderma pigmentosum (XP) fibroblasts, XP12BE, were uv-irradiated and then incubated with cytosine arabinoside and hydroxyurea for 4 hr to inhibit the polymerase step of DNA excision repair. By alkaline elution, DNA single-strand breaks (SSB) were detected in XP cells with this regimen with an efficiency of 0.1-0.2 SSB per 10/sup 9/ daltons of DNA per J m/sup -2/. There was an approximately linear relation between the SSB frequency and uv dose over a range of 0.2 to 25 J m/sup -2/. This effect was approximately two orders of magnitude greater in excision-proficient normal human fibroblasts than in XP cells. These results support the conclusion that a low residual level of DNA excision repair occurs in XP group A cells and that the SSB generated during this repair can be accumulated with this polymerase inhibitor.
- Research Organization:
- National Cancer Inst., Bethesda, MD
- OSTI ID:
- 5849805
- Journal Information:
- Radiat. Res.; (United States), Vol. 93:1
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
DNA
BIOLOGICAL RADIATION EFFECTS
STRAND BREAKS
RADIOINDUCTION
BIOLOGICAL REPAIR
ENZYME INHIBITORS
EXPERIMENTAL DATA
EXTREME ULTRAVIOLET RADIATION
HYDROXYUREA
XP CELLS
AMIDES
ANIMAL CELLS
BIOLOGICAL EFFECTS
BIOLOGICAL RECOVERY
DATA
ELECTROMAGNETIC RADIATION
HYDROXY COMPOUNDS
INFORMATION
NUCLEIC ACIDS
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
RADIATION EFFECTS
RADIATIONS
RECOVERY
REPAIR
ULTRAVIOLET RADIATION
560111* - Radiation Effects on Biochemicals- In Vitro- (-1987)