Investigation of nano- and balk ZnO particles effects on genes expression level of peroxidase and Δ1- pyrroline-5-carboxylate synthetase and peroxidase activity and proline content in Lepidiumdraba seedlings

Evaluation effects of ZnO nanoparticles on peroxidase activity, gene expression of peroxidase enzyme, proline content and expression of proline-5-carboxylate synthetase (P5CS) gene in L. draba seedlings in compared to the effects of its balk form.

L. draba seedlings were grown in the presence of different concentrations of these particles for 7 days in fully-random designs with three repetitions; thereafter the mentioned parameters were measured.

While the peroxidase activity was significantly evaluated in the presence of nano and balk particle in the concentration more than 100 and 50 mg/L respectively, in them, the gene expression level of peroxidase was the same as the control. On the other hand, in the treated seedlings, proline content was significantly increased in accordance to the rising nanoparticle doses in media, while, no significant difference was seen in the P5CS gene expression in different treatments rather than control sample. In the balk treated seedlings, content of this amino acid were significantly increased up to 100 mg/L concentrations and dramatically decreased in the presence of doses more than 250 mg/L in compared to the control sample. Gene expression level of P5CS was the same as the control in the presence of the balk form up to 500 mg/L and significantly decreased at the highest concentration.

Based on the results, it seems that nanoparticle has fewer effects rather than the balk form on the mentioned parameters, which may be due to release less Zn ion in this condition.