Modeling DNA Methylation Profiles and Epigenetic Analysis of Safflower (Carthamus tinctorius L.) Seedlings Exposed to Copper Heavy Metal

Heavy metals are chemical elements with high density that can be toxic or poisonous even at low concentrations. They are widely distributed in the environment due to industrial activities, mining, pesticide use, automotive emissions and domestic wastes. This study aimed to investigate the toxic effects of copper (Cu) heavy metal on safflower plants in terms of genetic and epigenetic parameters. Safflower seeds were exposed to different concentrations of Cu heavy metal solution (20, 40, 80, 160, 320, 640, 1280 mg L-1) for three weeks, and changes in the genomic template stability (GTS) and methylation pattern in the root tissues were analyzed using PCR and coupled restriction enzyme digestion-random amplification (CRED-RA) techniques. The results indicated that high doses of Cu have genotoxic effects on the genome of safflower plants. Epigenetic analysis revealed four different methylation patterns, with the highest total methylation rate of 95.40% observed at a 20 mg L-1 concentration, and the lowest rate of 92.30% observed at 160 mg L-1. Additionally, the maximum percentage of non-methylation was detected at 80 mg L-1. These results suggest that changes in the methylation patterns can serve as an important mechanism of protection against Cu toxicity. Furthermore, safflower can be used as a biomarker to determine the pollution in soils contaminated with Cu heavy metal.

Automated summary

Heavy metals are toxic and widely distributed in the environment. This study investigated the toxic effects of copper heavy metal on safflower plants in terms of genetic and epigenetic parameters. The results showed that high doses of copper had genotoxic effects on the safflower genome. Epigenetic analysis revealed different methylation patterns, indicating that changes in methylation can serve as a mechanism of protection against copper toxicity. Safflower can also be used as a biomarker to determine soil pollution caused by copper heavy metal.