IRT1 and ZIP2 were involved in exogenous hydrogen-rich water-reduced cadmium accumulation in Brassica chinensis and Arabidopsis thaliana

The results of Cd (cadmium) concentration, Cd2+ fluorescent staining, NMT (non-invasive micro-test technology) analysis of Cd absorption revealed the remarkably positive role of HRW in reducing Cd uptake by root of pak choi seedlings. BcIRT1 (iron-regulated transporter 1) and BcZIP2 (zinc-regulated transporter protein 2) are the main Cd transporters in pak choi, but their roles in the process of HRW-reduced Cd uptake is still far from being answered. In this study, we specifically verified the function of IRT1 and ZIP2 in HRW-reduced Cd absorption in pak choi and Arabidopsis thaliana. Heterologous and homologous expression in Arabidopsis thaliana displayed that Cd concentrations in wild-type (Col-0) and transgenic A. thaliana of IRT1 and ZIP2 were significantly reduced by HRW, except for irt1- and zip2-mutant. NMT detection showed that HRW not only decreased Cd2+ influx in root of WT and transgenic lines, but also enhanced the competition between Zn and Cd. Taken together, the HRW-induced reduction of Cd accumulation in plants may be result from depressing the expression of BcIRT1 and BcZIP2 and affecting the preference of BcIRT1 and BcZIP2 in ion uptake.

Automated summary

The study shows that hydrogen-rich water (HRW) plays a positive role in reducing cadmium uptake by the roots of pak choi seedlings, possibly by inhibiting Cd2+ influx and affecting the expression of Cd transporter proteins.