MODELING OF DNA DAMAGE REPAIR INDUCED BY HEAVY IONS IN MAMMALIAN CELLS

In this paper the mathematical description of main DNA repair pathways of single-strand break (SSB), base damage (BD), and double-strand break (DSB) in mammalian and human cells are proposed. The model shows key molecular mechanisms of DNA recovery through the single-strand DNA repair, base excision repair (BER), nonhomologous end-joining (NHEJ). To formalize the molecular mechanisms the dynamic system of differential equations describing the chemical kinetics of protein interactions according the modern concepts of molecular biology is constructed. Taking into account three repair pathways it makes possible to describe the cell's response to heavy charged particles influence. The proposed model is validated for main mechanisms of SSB repair, BER, NHEJ. In the course of the work, the time-dependent dynamics of formations and repairs of key DNA damage types (BD, SSB, DSB, cluster damages) in human cells under 56Fe ions (E = 600 Mev/u) exposure are calculated. A comparative analysis of the DNA damages and theirs repair under 12C (E = 270 MeV/u) and 56Fe (E = 600 Mev/u) ions exposure at 1 Gy was carried out.