Selenium-enhanced arsenic uptake by As-hyperaccumulators Pteris vittata and Pteris cretica is known, but how it impacts antimony (Sb) uptake and associated mechanisms are unclear. Here, we investigated the effects of 2.5 μM selenate (Se2.5) on Sb uptake by two plants after growing for 10 days under hydroponics containing 10 or 50 μM antimonate (SbV) (Sb10 or Sb50). Both plants were efficient in taking up SbV, which was reduced to SbIII (17–40 %) and mainly accumulated in the roots (86−97 %). The addition of Se increased the Sb contents by 78–97 and 29–33 % to 242–1358 and 132–697 mg kg−1 in P. vittata and P. cretica roots. Compared with the Sb10 and Sb50 treatments, addition of Se increased the SbV reduction, with more increase in P. vittata than P. cretica roots (181–273 % vs. 17–29 %). Enhanced GSH-GSSG cycle mediated by glutathione peroxidase (GPX) and glutathione reductase (GR) may play an important role in SbV reduction in the roots. Compared with the Sb treatments, addition of Se increased the GPX and GR activity by 71–97 and 2–50 % in P. vittata roots, and 59–153 and 22–63 % in P. cretica roots. Besides, Se upregulated the expression of arsenate reductases PvHAC1 and PvACR2 in P. vittata roots by 1.7−3.4 folds but not in P. cretica. Se-enhanced SbV reduction in P. vittata explains why it was more effective in Sb accumulation than P. cretica. Taken together, Se is effective in increasing the Sb uptake in both plants probably by promoting SbV reduction via GSH-GSSG cycle and/or PvHAC1/PvACR2, suggesting that Se may be used to enhance phytostabilization of Sb-contaminated soils.

中文翻译：

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硒通过促进锑酸盐减少来增加 As-hyperaculator Pteris vittata 和 Pteris cretica 中的锑摄取：GSH-GSSG 循环和砷酸盐还原酶 HAC1/ACR2


硒增强砷被 As-hypercumulator Pteris vittata 和 Pteris cretica 吸收是已知的，但它如何影响锑 （Sb） 的摄取和相关机制尚不清楚。在这里，我们研究了 2.5 μM 硒酸盐 （Se2.5） 在含有 10 或 50 μM 锑酸盐 （SbV） （Sb10 或 Sb50） 的水培下生长 10 天后对两株植物 Sb 吸收的影响。两种植物都能有效地吸收 SbV，其降低为 SbIII （17-40 %），主要在根中积累 （86-97 %）。添加 Se 使 P. vittata 和 P. cretica 根中的 Sb 含量增加了 78-97% 和 29-33%，达到 242-1358 和 132-697 mg kg-1。与 Sb10 和 Sb50 处理相比，添加 Se 增加了 SbV 的降低，P. vittata 的增加比 P. cretica 根增加更多（181-273 % 对 17-29 %）。谷胱甘肽过氧化物酶 （GPX） 和谷胱甘肽还原酶 （GR） 介导的增强 GSH-GSSG 循环可能在根系 SbV 减少中发挥重要作用。与 Sb 处理相比，添加 Se 使 P. vittata 根的 GPX 和 GR 活性提高了 71-97 和 2-50%，P. cretica 根的 GPX 和 GR 活性提高了 59-153 和 22-63%。此外，Se 将 P. vittata 根中砷酸盐还原酶 PvHAC1 和 PvACR2 的表达上调了 1.7−3.4 倍，但在 P. cretica 中则不上调。P. vittata 中 Se 增强的 SbV 降低解释了为什么它在 Sb 积累中比 P. cretica 更有效。综上所述，Se 可能通过 GSH-GSSG 循环和/或 PvHAC1/PvACR2 促进 SbV 减少，从而有效增加两种植物对 Sb 的吸收，这表明 Se 可用于增强 Sb 污染土壤的植物稳定性。