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

Abstract

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.

Editorial for the Special Issue “Phytotoxicity of Heavy Metals in Contaminated Soils”

“…At high concentrations, heavy metals act as catalysts in the oxidative degradation of biological macromolecules, leading to DNA damage by oxidative stress. Bölükbaşı and Karakaş [ 2 ] exposed Carthamus tinctorius L. (Safflower) seeds to different concentrations of Cu heavy metal solution and reported that high doses of Cu have a genotoxic effect on safflower plants. The presence of a substantial amount of polymorphism in the safflower plants exposed to Cu heavy metal stress was observed, as well as altered DNA methylation patterns, a crucial defence mechanism utilized by the safflower plant.…”