Fate of lesions that elicit sister chromatid exchanges (FLE-SCE) produced in DNA by alkylating agents in vivo.
A study was made on the effect of ethyl methanesulfonate (EMS) or dimethylnitrosamine (DMN) on the frequency of SCE occurring in the first, in the second or at the same locus in both divisions. This was done with a previously reported in vivo protocol which allowed us to determine the fate of lesions that elicit SCE (FLE-SCE) in two cell divisions after mutagen treatment. The results showed that EMS-induced DNA lesions that cause SCE are persistent, and that some of them were produced in the second-division or were generated from SCE non-inducing lesions. We inferred this by the analysis of the response in cell populations. DMN seems to induce SCE mainly during the second division, but by inhibiting DNA synthesis as was interpreted from the cell frequency distribution with respect to the number of SCE in first and in second cell division.
Morales-Ramírez
P
P
Departamento de Radiobiología, Instituto Nacional de Investigaciones Nucleares, México, D.F. Mexico.
Rodríguez-Reyes
R
R
Vallarino-Kelly
T
T
D000477:Alkylating Agents / Q000633:toxicity*; D000818:Animals; D004247:DNA / Q000187:drug effects*; D004249:DNA Damage; D004128:Dimethylnitrosamine / Q000633:toxicity*; D005020:Ethyl Methanesulfonate / Q000633:toxicity*; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D012854:Sister Chromatid Exchange
D000477:Alkylating Agents; D004247:DNA; D005020:Ethyl Methanesulfonate; D004128:Dimethylnitrosamine