Rice metal-nicotianamine transporter, OsYSL2, is required for the long-distance transport of iron and manganese
Rice metal-nicotianamine transporter, OsYSL2, is required for the long-distance transport of iron and manganese
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DOI：
10.1111/j.1365-313x.2010.04158.x
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发表时间：
2010-05-01
期刊：
影响因子：
7.2
通讯作者：
Nishizawa, Naoko K.
中科院分区：
文献类型：
--
作者：
Ishimaru, Yasuhiro;Masuda, Hiroshi;Nishizawa, Naoko K.
水稻（Oryza sativa）在世界上大多数人口的饮食中是不可或缺的。因此，改变铁（Fe）的吸收和动态平衡，从而增加铁在籽粒中的积累是一个重要的靶点。我们之前分离了OsYSL2，这是一种功能性铁[Fe(II)]-和锰[Mn(II)]-烟胺复合物转运蛋白，在韧皮部细胞和发育中的种子中表达。我们制备了OsYSL2的RNAi （OsYSL2i）和过表达系（OXOsYSL2）。OsYSL2i系营养发育阶段，铁、锰在茎部含量降低，铁在根部含量升高。在繁殖阶段，正电子发射示踪成像系统分析显示，铁在OsYSL2i中向芽和种子的转运受到抑制。OsYSL2i种子中铁和锰的含量降低，尤其是胚乳中铁和锰的含量降低。此外，与野生型相比，OXOsYSL2的铁浓度在种子和芽中较低，而在根中较高。此外，当蔗糖转运子启动子驱动OsYSL2表达时，精米中的铁浓度比野生型高4.4倍。这些结果表明，OsYSL2表达的改变改变了铁的定位，OsYSL2是铁转运的关键铁-烟胺转运蛋白，对铁的转运至关重要，特别是在芽和胚乳中。
P>Rice (Oryza sativa) is indispensable in the diet of most of the world's population. Thus, it is an important target in which to alter iron (Fe) uptake and homeostasis, so as to increase Fe accumulation in the grain. We previously isolated OsYSL2, a functional iron [Fe(II)]- and manganese [Mn(II)]-nicotianamine complex transporter that is expressed in phloem cells and developing seeds. We produced RNAi (OsYSL2i) and overexpression lines (OXOsYSL2) of OsYSL2. At the vegetative stage in an OsYSL2i line, the Fe and Mn concentrations were decreased in the shoots, and the Fe concentration was increased in the roots. At the reproductive stage, positron-emitting tracer imaging system analysis revealed that Fe translocation to the shoots and seeds was suppressed in OsYSL2i. The Fe and Mn concentrations were decreased in the seeds of OsYSL2i, especially in the endosperm. Moreover, the Fe concentration in OXOsYSL2 was lower in the seeds and shoots, but higher in the roots, compared with the wild type. Furthermore, when OsYSL2 expression was driven by the sucrose transporter promoter, the Fe concentration in the polished rice was up to 4.4-fold higher compared with the wild type. These results indicate that the altered expression of OsYSL2 changes the localization of Fe, and that OsYSL2 is a critical Fe-nicotianamine transporter important for Fe translocation, especially in the shoots and endosperm.