Effect of various inhibitors of DNA synthesis on the repair of DNA photoproducts

Journal Article · Fri Sep 09 04:00:00 EDT 1983 · Biochim. Biophys. Acta - Gene Struct. Expr.; (United States)

DOI:https://doi.org/10.1016/0167-4781(83)90082-9· OSTI ID:6964074

Clarkson, J M; Mitchell, D L ^[1]

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1. University of Texas System Cancer Center, Smithville, TX (USA). Science Park-Research Division

The effect on DNA repair of several inhibitors of DNA synthesis has been investigated in CHO cells. Three assays were employed following ultraviolet irradiation of G/sub 1/ cells: unscheduled DNA synthesis, removal of antibody binding sites and alkaline elution. Cytosine arabinoside and aphidicolin were found to reduce unscheduled DNA synthesis in a dose-dependent manner without affecting the removal of antibody-binding sites. Strand rejoining was also inhibited. These results are consistent with the hypothesis that inhibition is due to premature chain termination during repair synthesis some time after excision of the lesion. Conversely, inhibition of unscheduled DNA synthesis by novobiocin is paralleled by inhibition of excision of the lesion. However, no inhibition of incision was apparent. Since nalidixic acid, an inhibitor of topoisomerase II, did not inhibit excision, it is unlikely that the primary site of action of novobiocin is this topoisomerase. The possibility that a second topoisomerase and/or a polymerase are affected is discussed in the light of previously-published data.

• OSTI ID: 6964074
• Journal Information: Biochim. Biophys. Acta - Gene Struct. Expr.; (United States), Journal Name: Biochim. Biophys. Acta - Gene Struct. Expr.; (United States) Vol. 740:4
• Country of Publication: United States
• Language: English

Related Subjects

560121* -- Radiation Effects on Cells-- External Source-- (-1987)
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
BIOLOGICAL EFFECTS
BIOLOGICAL RADIATION EFFECTS
BIOLOGICAL RECOVERY
BIOLOGICAL REPAIR
BIOSYNTHESIS
CELL CULTURES
DNA
ELECTROMAGNETIC RADIATION
ENZYME INHIBITORS
INHIBITION
NEAR ULTRAVIOLET RADIATION
NUCLEIC ACIDS
ORGANIC COMPOUNDS
RADIATION EFFECTS
RADIATIONS
RECOVERY
REPAIR
SYNTHESIS
TESTING
ULTRAVIOLET RADIATION