Berestyanaya A. Epigenetic aspects of radiation aging plants

The thesis devoted to the study of physiological, biochemical, molecular biological and epigenetic mechanisms of radiation-induced aging in monocarpic plants. Increasing tension hydrolytic processes under radiation induction of aging have been identified in flax cotyledons when irradiated with different doses of UV and X-ray. Experiments on cotyledons of flax and flowers of morning glory demonstrated an interconnection between increased rate of decay of chlorophylls and anthocyanin and increment in the activity of ribonucleases. Experimentally proved that under the influence of UV as well as X-rays methylation in transcribed region of the genome and satellite DNA changes significantly. Methylation occus in site specific DNA sequences depending on the stage of plant organ aging. It was established than the nature of cytosine methylation in site specific DNA sequences changed during aging in cotyledon of flax. When this is the case either hypomethylation or preservation of the previous level of methylation of cytosine in specific sequencts of DNA. The presented results confirm the validity of the hypothesis that aging in plants is controlled by epigenetic processes with the choice of a particular epigenome pattern.