[DNA damage in cells exposed to ionizing radiation].
Ionizing radiation induces variety of structural lesions in DNA of irradiated organisms. Their formation depends largely on the degree of cell oxygenation, the level of endogenous antioxidants, on DNA-protein complexes and compactization of DNA in the chromatin and activity of DNA repair systems. All ionizing radiation-induced DNA lesions can arbitrarily be divided into two groups. Group 1 includes singly damaged sites (single-sites): base modification, single-strand breaks, alkaline-labile sites (including a basic sites). Group 2 contains: locally multiply damaged sites (clustered lesions), double-strand breaks, intermolecular cross-links. The yields of lesions of group 2 increases with high linear energy transfer of radiation and these lesions play a dominant role in the radiation death, formation of chromosome and gene mutations, cell transformation.
Gaziev
A I
AI
Pushchino State University, Russia. gaziev@venus.iteb.serpukhov.su
D000818:Animals; D004249:DNA Damage / Q000528:radiation effects*; D006801:Humans; D011839:Radiation, Ionizing