Plants have the ability to colonize highly diverse environments. The zinc and cadmium hyperaccumulator Arabidopsis halleri has adapted to establish populations on soils covering an extreme range of metal availabilities. The A. halleri ZIP6 gene presents several hallmarks of hyperaccumulation candidate genes: it is constitutively highly expressed in roots and shoots and is associated with a zinc accumulation quantitative trait locus. Here, we show that AhZIP6 is duplicated in the A. halleri genome. The two copies are expressed mainly in the vasculature in both A. halleri and Arabidopsis thaliana, indicative of conserved cis regulation, and acquired partial organ specialization. Yeast complementation assays determined that AhZIP6 is a zinc and cadmium transporter. AhZIP6 silencing in A. halleri or expression in A. thaliana alters cadmium tolerance, but has no impact on zinc and cadmium accumulation. AhZIP6‐silenced plants display reduced cadmium uptake upon short‐term exposure, adding AhZIP6 to the limited number of Cd transporters supported by in planta evidence. Altogether, our data suggest that AhZIP6 is key to fine‐tune metal homeostasis in specific cell types. This study additionally highlights the distinct fates of duplicated genes in A. halleri.

中文翻译：

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拟南芥锌和镉ZIP6转运蛋白的两个副本对镉的耐受性具有明显的影响。

植物具有在高度多样化的环境中定殖的能力。锌和镉超富集拟南芥已适应在土壤中建立覆盖范围极广的金属利用率的种群。该A. halleri ZIP6基因礼物的超富集的候选基因几个特点：它是组成非常根和枝条中表达，并与锌的积累数量性状位点有关。在这里，我们显示AhZIP6在A. halleri基因组中重复。这两个拷贝主要在A. halleri和拟南芥的脉管系统中表达，表明顺式是保守的调节，并获得部分器官专长。酵母互补测定确定AhZIP6是锌和镉转运蛋白。在A. halleri中沉默AhZIP6或在拟南芥中表达可以改变镉耐受性，但对锌和镉积累没有影响。使AhZIP6沉默的植物在短期暴露后显示出减少的镉吸收，使AhZIP6增加到植物证据支持的有限数量的Cd转运蛋白上。总而言之，我们的数据表明，AhZIP6是微调特定细胞类型中金属稳态的关键。这项研究还强调了A. halleri中重复基因的独特命运。