Modeling the effect of radiations with different linear energy transfer on bacterial cells
- Paper number
IAC-10.A1.4.11
- Author
Mr. Oleg Belov, Joint Institute for Nuclear Research, Russia
- Year
2010
- Abstract
Research on the genetic effect of radiations of different quality on biological objects is an important task of space radiobiology related to the performance of interplanetary flights. One of the major adverse effects of the heavy nuclei of galactic radiation is that they induce different types of mutations associated with carcinogenesis. Detailed examination of these issues requires not only experimental research but also applying mathematical modeling methods to the main mechanisms of the induced mutation process. Modeling different mechanisms of the genetic effect of radiations of different quality in cells of higher organisms and humans is difficult without a detailed analysis of the mutation process in bacterial cells. The main mechanism of the formation of mutations in bacterial cells consists in the functioning of the SOS repair system, which is a complicated chain of protein interactions leading to the fixation of DNA primary lesions as gene mutations. In modeling a SOS response, the quantitative estimation of the inducing signal triggering the SOS system is the most difficult task. The main DNA lesions caused by ionizing radiations are single- and double-strand breaks, base lesions, and clustered DNA lesions. The latter two classes of lesions make the main contribution to the formation of an inducing signal. In this work, a mathematical model is developed which describes the dynamics of the inducing signal of the SOS system in Escherichia coli bacterial cells under radiations with different linear energy transfer. Using the earlier model concepts (Krasavin and Kozubek, 1999), the process of the formation of the main pre-mutation DNA lesions is described quantitatively. Also, a model is developed which describes the main DNA repair types leading to the formation of an inducing signal for the SOS system of E. coli cells. Together with the earlier model concepts (Belov et al., 2009), the obtained results are an important step towards the creation of a generalized model of the mutation process induced in bacterial cells by different damaging factors. The proposed approaches will be successfully used in the development of the models of the mutation process in cells of organisms with a higher genome - mammals and humans.
- Abstract document
- Manuscript document
(absent)