The Nature of the Alkylation Lesion in Mammalian Cells
- 1 January 1975
- book chapter
- Published by Springer Nature
Abstract
Methylating agents may produce as many as nine alkylated purine and pyrimidine adducts in DNA, as well as forming phosphotriesters and inducing apurinic sites and strand breaks. Although some of these products are formed in proportionately small amounts, there are sufficient sites affected in the DNA of a mammalian cell to make even the most minor product of potential biological significance. It is not possible to specify the exact reaction sites resulting in biological damage, but it is possible to quantitate the excision-repair of such damage both in the bulk of the DNA and at DNA growing points. Excision-repair can be measured in the bulk of the DNA by determining the specific activity of the NaC1 eluate of a benzoylated naphthoylated DEAE-cellulose column of extracts of cells after treatment and incubation in the presence of hydroxyurea and labeled thymidine. The average number of nucleotides inserted per methyl methanesulfonate-induced methyl group is 0.1, per apurinic site is 9. Repair in growing-point regions after methyl methanesulfonate treatment occurs to approximately the same extent as in the bulk of the DNA.Keywords
This publication has 29 references indexed in Scilit:
- Reaction of N-methyl-N-nitrosourea (MNUA) with 32P-labelled DNA: evidence for formation of phosphotriestersChemico-Biological Interactions, 1973
- Methylation of DNA by 3H-14C-methyl-labelled N-methyl-N-nitrosourea—Evidence for transfer of the intact methyl groupChemico-Biological Interactions, 1973
- DNA replication in human cells treated with methyl methanesulfonateMutation Research - Fundamental and Molecular Mechanisms of Mutagenesis, 1973
- The value of hydroxyurea in assessing repair synthesis of DNA in HeLa cellsChemico-Biological Interactions, 1972
- Reaction of alkylating mutagens and carcinogens with nucleic acids: detection and estimation of a small extent of methylation at O-6 of guanine in DNA by methyl methanesulphonate in vitroChemico-Biological Interactions, 1972
- Repair replication in mammalian cells after X-irradiationMutation Research - Fundamental and Molecular Mechanisms of Mutagenesis, 1972
- Endonuclease II of Escherichia coli. Degradation of partially depurinated deoxyribonucleic acidBiochemistry, 1971
- Failure of alkylated HEp.2 cells to replicate newly synthesized DNAMutation Research - Fundamental and Molecular Mechanisms of Mutagenesis, 1971
- Quantitative aspects of the repair of alkylated DNA in cultured mammalian cellsChemico-Biological Interactions, 1971
- Specific excision of methylation products from DNA of Escherichia coli treated with N-methyl-N′-nitro-N-nitrosoguanidineChemico-Biological Interactions, 1970