Quantitative polymorphism of tandem repeats as a method of epigenetic regulation of the of human cells response to oxidative stress

Abstract

The spatial organization of chromatin is important for the normal functioning of the cell. Genome repeat cluster sizes can affect the chromatin spatial configuration and function. The 1q12 heterochromatin loci movement from the periphery to the center of the nucleus is the cells’ universal response to various types of stress. We hypothesized that a large 1q12 domain could affect chromatin movement, thereby inhibiting adaptive response (AR). Using the FISH method, we shown that in the control, 1q12 loci are located near the surface of the nucleus; in the lymphocyte nuclei of schizophrenic patients and irradiated control cells, 1q12 loci are located in the central regions of the nucleus. During prolonged cultivation, the irradiated cells with a large Large f-SatIII amount die and the population is enriched with the cells with low f-SatIII content. In intact SZ patients’ lymphocytes and in irradiated cells we found an increase in SATIII RNA levels. The size of heterochromatin 1q12 loci in human cells can affect to the proliferation and cells’ adaptive response to stress. Quantitative polymorphism of tandem genome repeats is one of the epigenetic mechanisms of genome expression’s regulation.