Epigenetic investigation of the amaranthus hypochondriacus genotype exposed to salt stress

Amaranth (Amaranthus hypochondriacus) is classified as a pseudocereal due to prsence of high amount of protein, carbohydrates, and essential minerals. It is also significant for sustainable agricultural production owing to its remarkable tolerance to various environmental stresses like salt stress, throughout its life cycle, negatively impacting growth and development, with yield losses. Plants, have evolved various genomic defense mechanisms against these stresses. Among these mechanisms, epigenetic modifications regulate gene expression at the transcriptional level, enhancing stress tolerance. the study aimed to investigate DNA methylation based changes in salt-stressed A. hypochondriacus plants within the scope of epigenetic studies. The experimental plants were initially grown under in vitro conditions on Murashige& Skoog (MS) medium for four weeks. It was followed by their exposure to 200 mM NaCl for durations of 3, 6, and 9 days. Subsequently, DNA was isolated from root and leaf tissues, and the CRED-iPBS method was applied to determine alterations in DNA methylation patterns. According to the results, average polymorphism percentage in leaf tissues was 38.33%, 44.42%, and 54.16% after 3, 6, and 9 daysrespectively, while corresponding percentages in root tissues were 40.50%, 53.85%, and 58.33%. Class-based methylation analysis revealed that total methylation rates (TMO) in roots decreased from 68.4% to 64.3%, indicating slight hypomethylation, whereas leaves maintained methylation levels without significant decline. Thus, a loss of methylation in roots and relative methylation maintenance in leaves was observed. These findings demonstrate that epigenetic responses exhibit different profiles in root and leaf tissues and display significant variations depending on the duration of stress. The study indicates that differences in DNA methylation are associated with responses to salt stress. It is anticipated that the obtained data will provide insights for similar studies and contribute to a deeper understanding of the related epigenetic processes.