Iron deficiency enhances cadmium uptake and translocation mediated by the Fe2+ transporters OsIRT1 and OsIRT2 in rice
Iron deficiency enhances cadmium uptake and translocation mediated by the Fe2+ transporters OsIRT1 and OsIRT2 in rice
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DOI：
10.1111/j.1747-0765.2006.00055.x
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发表时间：
2006-08-01
影响因子：
2
通讯作者：
Nishizawa, Naoko K.
中科院分区：
文献类型：
--
作者：
Nakanishi, Hiromi;Ogawa, Ippei;Nishizawa, Naoko K.
在水稻生殖生长阶段，如果从稻田中释放积水（间歇灌溉），镉（Cd）在水稻籽粒中的积累会增加。积水的释放创造了好氧土壤条件，在此条件下，镉变得可溶，铁（Fe）的溶解度降低。我们推测，水稻缺铁诱导铁的吸收和转运，镉也采取和转运在整个过程中。水培缺铁水稻吸收更多的镉比铁充足的水稻，铁的存在增强了镉的运输到地上部。表达水稻铁转运蛋白OsIRT1和OsIRT2的酵母突变体对Cd的敏感性增强，表明OsIRT1和OsIRT2对Cd有吸收作用。我们讨论了镉在水稻籽粒中的积累在生殖阶段的可能性是由铁运输系统介导的。
Cadmium (Cd) accumulation in rice grains is enhanced if ponded water is released from paddy fields during the reproductive stage (intermittent irrigation). The release of ponded water creates aerobic soil conditions under which Cd becomes soluble and iron (Fe) solubility decreases. We hypothesized that Fe shortage in rice induces Fe uptake and translocation and that Cd is also taken up and translocated throughout this process. Hydroponically cultured Fe-deficient rice absorbed more Cd than did Fe-sufficient rice, and the presence of Fe enhanced the translocation of Cd to the shoots. Yeast mutants expressing OsIRT1 and OsIRT2, which encode the rice Fe2+ transporter, became more sensitive to Cd, suggesting that Cd was absorbed by OsIRT1 and OsIRT2. We discuss the possibility that Cd accumulation in rice grains during the reproductive stage is mediated by the Fe transport system.