Iron toxicity-induced DNA damage, DNA methylation changes, and LTR retrotransposon polymorphisms in Zea mays

Abstract

The impact of Fe2+ (iron)toxicity on genomic instability, DNA methylation status, and Long Terminal Repeat Retrotransposons (LTR RTs) polymorphisms on Zea mays is unknown. We investigated the toxicity of Fe2+ using Random Amplified Polymorphic DNA (RAPD), Coupled Restriction Enzyme Digestion-Random Amplification (CRED-RA) and Inter Retrotransposon Amplified Polymorphism (IRAP) assays in Zea mays seedlings, respectively. The results indicated that each dose of FeSO4 (50, 100, 200, and 300 mg/L) had a reducing effect on Genomic Template Stability (GTS) and increasing in RAPD pattern changes (DNA damage). The value of DNA methylation rised gradually depending on FeSO4 doses. Moreover, five LTR RTs (Wltr2105, Nikita-N57, Sukkula, Nikita-E2647, and Stowaway) of the maize genome revealed polymorphism in all FeSO4 doses. Furthermore, the present study indicated that there is a relationship between DNA methylation alterations and LTR RTs mobilization. It was concluded that iron caused DNA methylation changes as well as genotoxic damage in the maize genome. Also, considering the increase in some LTR RTs polymorphism we can say that it may be a part of the defense mechanism of the plant during stress