DNA methylation regulates the expression of salt tolerance gene FtNHX1 in Tartary buckwheat

DNA methylation is an important part of epigenetics, which can regulate gene expression, cell differentiation, growth and development in plants. In this study, the salt-sensitive variety Chuanqiao No.2 of Tartary buckwheat was used as experimental material. Different concentrations of 5-azaC were used to infect Tartary buckwheat leaves and combined with gene expression analysis, it is determined that the appropriate concentration of 5-azaC treatment is 100 µM. DNA methylation often occurs in the gene promoter region, causing gene transcription changes, and thus regulating the response to salt stress. By CpG island prediction and promoter region methylation site analysis of FtNHX1 gene, it was found that FtNHX1 gene expression was significantly regulated by DNA methylation. Moreover, after salt stress for 6 h, DNA methylation rate of FtNHX1 gene was increased. This increase of DNA methylation rate in a short time may inhibit over-expression of FtNHX1 gene.