Open AccessEffects of X‐Ray Irradiation on Deoxyribonucleotide and DNA Synthesis in Cultured Mouse Embryo Cells
Author(s) -
Slaby Ivan,
Skoog Lambert,
Thelander Lars
Publication year - 1971
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1971.tb01467.x
Subject(s) - ribonucleotide reductase , deoxyribonucleotides , deoxyribonucleotide , dna synthesis , ribonucleotide , thymidine , dna , thymidine kinase , microbiology and biotechnology , biology , embryo , biochemistry , deoxyribonucleoside , irradiation , chemistry , genetics , nucleotide , protein subunit , oligonucleotide , physics , nuclear physics , virus , herpes simplex virus , gene
Cultured secondary mouse embryo cells were irradiated in G 1 ‐phase or in S‐phase with doses of X‐rays which resulted in a depression of DNA synthesis. Pools of dTTP and dATP, as well as the activities of the enzymes ribonucleotide reductase and thymidine kinase were measured at different times after irradiation. After irradiation of G 1 ‐cells the pool sizes of both deoxyribonucleotides and the activity of ribonucleotide reductase—but not of thymidine kinase—were depressed in parallel with DNA synthesis, as compared to the controls. On the other hand, irradiation in S‐phase resulted in an immediate small increase in the pool sizes of the deoxyribonucleotides. Ribonucleotide reductase activity was not affected at early time points after irradiation. Our results indicate that the decreased DNA synthesis observed after X‐ray irradiation was not caused by a depletion of deoxyribonucleotide pools.