Inhibition of uracil-DNA glycosylase increases SCEs in BrdU-treated and visible light-irradiated cells

Journal Article · Fri Nov 01 04:00:00 EST 1985 · Exp. Cell Res.; (United States)

DOI:https://doi.org/10.1016/0014-4827(85)90501-4· OSTI ID:6227901

Maldonado, A; Hernandez, P; Gutierrez, C

The authors have approached the study of the ability of different types of lesions produced by DNA-damaging agents to develop sister-chromatid exchanges (SCEs) by analyzing SCE levels observed in Allium cepa L cells with BrdU-substituted DNA and exposed to visible light (VL), an irradiation which produces uracil residues in DNA after debromination of bromouracil and enhances SCE levels but only above a certain dose. They have partially purified an uracil-DNA glycosylase activity from A. cepa L root meristem cells, which removes uracil from DNA, the first step in the excision repair of this lesion. This enzyme was inhibited in vitro by 6-amino-uracil and uracil but not by thymine. When cells exposed to VL, at a dose that did not produce per se an SCE increase, were immediately post-treated with these inhibitors of uracil-DNA glycosylase, a significant increase in SCE levels was obtained. Moreover, SCE levels in irradiated cells dropped to control level when a short holding time elapsed between exposure to VL and the beginning of post-treatment with the inhibitor. Thus, our results showed that inhibitors of uracil-DNA glycosylase enhanced SCE levels in cells with unifilarly BrdU-substituted DNA exposed to visible light; and indicated the existence of a very rapid repair of SCE-inducing lesions produced by visible light irradiation of cells with unifilarly BrdU-containing DNA.

• Research Organization: Instituto de Biologia Celular, Madrid, Spain
• OSTI ID: 6227901
• Journal Information: Exp. Cell Res.; (United States), Journal Name: Exp. Cell Res.; (United States) Vol. 1; ISSN ECREA
• Country of Publication: United States
• Language: English

Related Subjects

560400* -- Other Environmental Pollutant Effects
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ALLIUM CEPA
ANTIMETABOLITES
AZINES
BIOLOGICAL RECOVERY
BIOLOGICAL REPAIR
BROMOURACILS
BUDR
CHROMOSOMAL ABERRATIONS
DNA REPAIR
DRUGS
ELECTROMAGNETIC RADIATION
ENZYMES
GLYCOSYL HYDROLASES
HETEROCYCLIC COMPOUNDS
HYDROLASES
HYDROXY COMPOUNDS
INHIBITION
KINETICS
MUTATIONS
NUCLEOSIDES
NUCLEOTIDES
ORGANIC BROMINE COMPOUNDS
ORGANIC COMPOUNDS
ORGANIC HALOGEN COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
PLANTS
PYRIMIDINES
RADIATIONS
RECOVERY
REPAIR
RIBOSIDES
SISTER CHROMATID EXCHANGES
THYMINE
URACILS
VISIBLE RADIATION