Inhibition of Nitrate Transporter 1.1-Controlled Nitrate Uptake Reduces Cadmium Uptake in Arabidopsis
Inhibition of Nitrate Transporter 1.1-Controlled Nitrate Uptake Reduces Cadmium Uptake in Arabidopsis
复制标题
抑制硝酸盐转运蛋白 1.1 控制的硝酸盐吸收可减少拟南芥中的镉吸收
DOI：
10.1104/pp.114.243766
复制
发表时间：
2014-10-01
期刊：
影响因子：
7.4
通讯作者：
Jin, Chong Wei
中科院分区：
文献类型：
--
作者：
Mao, Qian Qian;Guan, Mei Yan;Jin, Chong Wei
确定减少镉在植物中积累的机制是最大限度地减少受污染作物中镉的膳食吸收的先决条件。在这里，我们表明，镉抑制硝酸盐转运蛋白1.1（NRT1.1）介导的硝酸盐（NO3-）的吸收在拟南芥（拟南芥）和损害NO3-根的稳态。在含NO3-的培养基中，NRT1.1突变体中NRT1.1功能的丧失导致根和芽中镉和其他几种金属的水平降低，并导致在镉存在下的更好的生物量生产，而在无NO3-的培养基中，NRT1.1突变体和野生型植物之间没有差异。这些结果表明，抑制NRT1.1活性减少镉的吸收，从而提高镉的耐受性在NO3-吸收依赖的方式。此外，使用治疗旋转系统，允许同步吸收NO3-和营养阳离子和异步吸收镉，nrt1.1突变体有类似的镉水平，野生型植物，但较低的营养金属水平，而相反的效果是使用治疗旋转允许同步吸收NO3-和镉和异步吸收营养阳离子。我们的结论是，虽然抑制NRT1.1介导的NO3-吸收镉可能有负面影响的氮营养在植物中，它有一个积极的影响，镉解毒，减少镉进入根系。NRT1.1可能通过一种共同的机制调节镉和其他阳离子的吸收。
Identification of mechanisms that decrease cadmium accumulation in plants is a prerequisite for minimizing dietary uptake of cadmium from contaminated crops. Here, we show that cadmium inhibits nitrate transporter 1.1 (NRT1.1)-mediated nitrate (NO3-) uptake in Arabidopsis (Arabidopsis thaliana) and impairs NO3- homeostasis in roots. In NO3--containing medium, loss of NRT1.1 function in nrt1.1 mutants leads to decreased levels of cadmium and several other metals in both roots and shoots and results in better biomass production in the presence of cadmium, whereas in NO3--free medium, no difference is seen between nrt1.1 mutants and wild-type plants. These results suggest that inhibition of NRT1.1 activity reduces cadmium uptake, thus enhancing cadmium tolerance in an NO3- uptake-dependent manner. Furthermore, using a treatment rotation system allowing synchronous uptake of NO3- and nutrient cations and asynchronous uptake of cadmium, the nrt1.1 mutants had similar cadmium levels to wild-type plants but lower levels of nutrient metals, whereas the opposite effect was seen using treatment rotation allowing synchronous uptake of NO3- and cadmium and asynchronous uptake of nutrient cations. We conclude that, although inhibition of NRT1.1-mediated NO3- uptake by cadmium might have negative effects on nitrogen nutrition in plants, it has a positive effect on cadmium detoxification by reducing cadmium entry into roots. NRT1.1 may regulate the uptake of cadmium and other cations by a common mechanism.