The incorporation of O4-methylthymidine into V79A cell DNA when present in the cell culture medium.
Saffhill, Roy Fox, Margaret
Saffhill, Roy
Fox, Margaret
Citations
Altmetric:
Abstract
When Chinese hamster V79A cells are cultured in the presence of O4-methyl-[6-3H]-thymidine the incorporation of this modified nucleoside into newly synthesised DNA is observed. The radioactivity incorporated has been identified as O4-methylthymidine by digesting the DNA to 3'-monophosphates with spleen phosphodiesterase followed by treatment with alkaline phosphatase to give O4-methylthymidine as the major radioactive product. The radioactivity associated with the latter co-chromatographs with authentic O4-methylthymidine in several chromatographic systems. Once incorporated the modified nucleoside appears to be rapidly removed from the DNA with half-life of 2-3 h. There is no evidence of demethylation of the O4-methylthymidine to give thymidine, in either the culture medium or within the cells once incorporated into DNA. Although the levels of incorporation observed are low, (being only 125 O4-methylthymidine residues per 10(8) thymidine residues at a modified nucleoside concentration of 10(-5) M), they may still be relevant as similar levels are apparently produced in the DNA of the cultured cells on treatment with biologically significant doses of carcinogenic alkylating agents.
Authors
Description
Date
1980-06
Publisher
Collections
Keywords
Type
Article
Citation
The incorporation of O4-methylthymidine into V79A cell DNA when present in the cell culture medium. 1980, 1 (6):487-93 Carcinogenesis