A quantitative assay of deoxyribonucleic acid strand breaks and their repair in mammalian cells

Journal Article · Thu Jul 15 00:00:00 EDT 1982 · Anal. Biochem.; (United States)

DOI:https://doi.org/10.1016/0003-2697(82)90229-9· OSTI ID:6373174

Blakely, W F ^[1]; Ward, J F; Joner, E I

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1. Univ. of California, San Diego

The alkaline/filter DNA elution technique measure single-strand DNA breaks in mammalian cells based on the DNA molecular weight dependent retention of the macromolecule on 2-..mu..m-pore-size filters. Described here is a modification of the technique which uses (/sup 3/H)thymidine-labeled DNA of ..gamma..-irradiated cells as an internal reference. Thus, an increased precision is obtained in the assessment of this type of DNA damage at biologically significant radiation doses (i.e., where cell survival occurs). The measure of DNA damage is based on the actual initial DNA elution rate, i.e., arithmetic ratio of the elution of ''test'' DNA (i.e., /sup 14/C-labeled DNA) relative to the elution of ''reference'' DNA (i.e., /sup 3/H-labeled DNA). The repair of this damage on postirradiation incubation of the cells is detected as a decrease in the rate of ''test'' DNA eluted relative to ''reference'' DNA from unincubated cells. For Chinese hamster V79-171 cells irradiated with 5 Gy (500 rads), repair can be resolved into two first-order processes having rate constants (at 24/sup 0/C) of approx.0.190 and approx.0.017 min/sup -1/.

• OSTI ID: 6373174
• Journal Information: Anal. Biochem.; (United States), Journal Name: Anal. Biochem.; (United States) Vol. 124:1; ISSN ANBCA
• Country of Publication: United States
• Language: English

Related Subjects

560111* -- Radiation Effects on Biochemicals-- In Vitro-- (-1987)
560121 -- Radiation Effects on Cells-- External Source-- (-1987)
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
AZINES
BIOLOGICAL EFFECTS
BIOLOGICAL RADIATION EFFECTS
BIOLOGICAL RECOVERY
BIOLOGICAL REPAIR
CHEMICAL ANALYSIS
DNA
ELECTROMAGNETIC RADIATION
GAMMA RADIATION
HETEROCYCLIC COMPOUNDS
IONIZING RADIATIONS
LABELLED COMPOUNDS
NUCLEIC ACIDS
NUCLEOSIDES
NUCLEOTIDES
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
PYRIMIDINES
QUANTITATIVE CHEMICAL ANALYSIS
RADIATION EFFECTS
RADIATIONS
RADIOINDUCTION
RECOVERY
REPAIR
RIBOSIDES
STRAND BREAKS
THYMIDINE
TRITIUM COMPOUNDS