The Amyloidogenesis in Descendants of Soybean Grow Under Radionuclide Contamination in Chornobyl Zone for Several Generations

Namik Rashydov
Institute Cell Biology and Genetic Engineering of Nas of Ukraine, Kyiv, Ukraine

Abstract

The prion-like proteins have a unique biochemical memory through destructive self-organizing conformation changes. Plants may synthesize prion-like proteins, able to self-assemble into amyloid fibrils, and amyloidogenesis may be activated in response to radionuclide pollution. Hence, we suggested that soybean plants that grew several generations at the Chornobyl aliened zone on the plot contaminated by 137Cs, 90Sr, 241Am, etc., might produce the appearance of proteins with prion-like properties. Our previous proteomic studies of soybean seeds sown for several years in soil contaminated with radioactive isotopes revealed that since the second generation, the contents of the cupin superfamily proteins, glycinin, and conglycinin proteins in the matured seeds were increased (Gábrišová et al., 2016). These prion-like proteins are known to trigger allergies. In the current study, the contents of prion-like proteins in soybean seeds were estimated by the ratio between alpha-helices and beta-sheets determined with the ATR-FTIR spectroscopy (Nicolet FTIR IS50 spectrometer, Thermo Fisher Scientific, USA). Obtained specters were analyzed with OMNIC software (Thermo Fisher Scientific, USA). Experimental soybean seeds were 3rd and 5th generations of plants’ descendants cultivated on soil contaminated with radionuclides. The data obtained indicate a significant increase in the proportion of β-sheets, up to 20-30%, in the soybean proteome from the radioactively contaminated territory, which may reveal the appearance of proteins with prion-like properties. At the same time, the ratio of β-sheets and α-helices decreased during three generations to control values. The results demonstrated a probable transition of the alpha-state of proteins to beta-conformation in descendants of plants that were cultivated on radionuclide-polluted soil, assuming increasing the contents of prion-like proteins. Experiments elucidating the appearance of prion-like proteins in plants could have consequences for mammal health, as consuming such proteins may be dangerous. Keywords: prion-like proteins, FTIR-spectrometry, proteins with β-sheets, radionuclide contamination. This work was supported by the National Research Foundation of Ukraine (project number 2020.02.0316).