Nesterenko O. Modification of radiobiological reactions of pea plants (Pisum sativum L.)with abiotic stressors

In the study biochemical, genetic, proteomic and morphological responses of Pisum sativum L . on acute radiation exposure in combination with salinity or hyperthermia were analyzed. For the first time we used a complex combined approach to study reactions of the pea seedlings to stressors after preliminary irradiation. The received results on growth parameters show that comparatively low doses of ionizing radiation assists plants in resistance to salt and temperature stressors, however this resistance is short term. These data could integrally characterize molecular, genetic, structural and metabolic changes in pea seedlings on their initial growth phase. For this purpose, the average growth rate of roots was compared with the theoretically expected growth rate that was calculated as an additive int eraction of stress factors. “Crosstalk” signal systems means the growth of organism’s resistance to one stress factor as a result of adaptation to another stressor. It is a result of interconnection and “dialogue” of various signal systems of plant. Signif icant deviation from additivity towards synergism or antagonism has been demonstrated in terms of growth parameters of plants, which may indicate the appearance of signal systems crosstalk. The quantification of this amino acid is useful to aassess the physiological status of signal systems crosstalk and more generally to understand stress tolerance of plants. For the first time the data concerning the impact of different types of stress and its combinations on the activity of plant mobile genetic elements were obtained. The appearance of new amplicons of LTR retrosposons were shown. It indi cates the possible destruction of epigenetic silencing and the increasing mobility of retro transposons. To understand the response to acute ionizing radiation in combination with salinity proteome changes were investigated. Analysis of proteomic data show ed that the stress factors being studied significantly affect to change both quality and quantitative amount in the content of pea seedlings proteins. As a result of the 2 DE analysis 223 protein spots were isolated, of which 54 statistically significantly differed in comparison with at least one of the experimental groups. We observed modification of synthesis of some proteins that belong to important signal systems . Their significant role in the stress signals transduction and in the processes of forming an active response to the unfavorable nfirmed by fluctuations proteins concentration between groups. The most widespread type of stressors interactions that was observed cooperative antagonistic.