APPLICATION OF RADIOBIOLOGICAL METHODS IN STUDYING CHROMATIN DIMINUTION IN CYCLOPS (COPEPODA, CRUSTACEA)

This paper briefly reviews the results of studies on chromosome radiosensitivity in Cyclops kolensis and Cyclops insignis (Copepoda, Crustacea), one of which exhibits chromatin diminution and the other does not. The results of studies of chromatin diminution using radiobiological methods have revealed a sharp decrease in the frequency of chromosomal aberrations in post-diminution cells and a low level of spontaneous chromosomal aberrations during early divisions. Gamma-radiation doses of 1 to 5 Gy slow down the cell cycle in C. kolensis and C. insignis embryos, while irradiation at doses of 20 Gy and higher stops embryo development at the 8–16-cell stage, while the process of chromatin diminution in C. kolensis embryos is not disrupted. A dose of 200 Gy blocks the process of chromatin diminution in C. kolensis.