Biopolym. Cell. 1986; 2(4):206-211.
Cell Biology
Peculiarities of the mutagenic effect of γ-rays and N-nitrosomethylurea in different periods of the DNA synthesis phase
1, 2Khakimov Kh. A., 2Ergashev A. K. E., 3Makedonov G. P., 3Akifjev A. P.
  1. Institute of Chemical Physics, Academy of Sciences of the USSR
    Moscow, USSR
  2. Institute of Experimental Biology of Plants, Academy of Sciences of the Uzbek SSR
    Tashkent, USSR
  3. N. I. Vavilov Institute of General Genetics, Academy of Sciences of the USSR
    Moscow, USSR


The sensitiveness of the DNA synthesis phase and its different periods to the mutagenic action of γ-irradiation in combination with 5-bromo-2-deoxyuridine (BUDR) and N-nitro-somethylurea was studied in 5-fluorodesoxyuridine-synchronized cells of winter wheat seedlings. In experiments with irradiation the radiosensitizing effect of BUDR in the early S phase was observed. This effect is not found in the middle and late S phases. Such differences in the sensitiveness of different periods of the S phase to the mutagenic action were absent in the experiment with NMU.


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