A mitochondrial magnesium transporter functions in Arabidopsis pollen development
A mitochondrial magnesium transporter functions in Arabidopsis pollen development
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线粒体镁转运蛋白在拟南芥花粉发育中发挥作用
DOI：
10.1093/mp/ssn031
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发表时间：
2008-07-01
期刊：
影响因子：
27.5
通讯作者：
Luan, Sheng
中科院分区：
文献类型：
--
作者：
Li, Le-Gong;Sokolov, Lubomir N.;Luan, Sheng
镁是植物细胞中丰富的二价阳离子，在许多生理过程中起着重要作用。我们之前已经描述了一个10个成员的拟南芥基因家族的鉴定，该基因家族编码假定的镁运输（MGT）蛋白。在这里，我们报道了MGT家族的成员AtMGT5，作为一种双功能的mg转运蛋白，以浓度依赖的方式运作，即它在微摩尔水平上作为mg的进口蛋白，并促进毫摩尔范围内的出口。AtMGT5蛋白定位于线粒体，表明AtMGT5介导细胞质和线粒体之间的mg运输。AtMGT5基因在花发育早期花药中特异表达。对两个独立的AtMGT5基因T-DNA插入突变体的检测表明，AtMGT5在花粉发育和雄性育性中起重要作用。该研究表明Mg2+在细胞质和线粒体之间的转运在植物雄性配子体发生中起着关键作用。
Magnesium is an abundant divalent cation in plant cells and plays a critical role in many physiological processes. We have previously described the identification of a 10-member Arabidopsis gene family encoding putative magnesium transport (MGT) proteins. Here, we report that a member of the MGT family, AtMGT5, functions as a dual-functional Mg-transporter that operates in a concentration-dependent manner, namely it serves as a Mg-importer at micromolar levels and facilitates the efflux in the millimolar range. The AtMGT5 protein is localized in the mitochondria, suggesting that AtMGT5 mediates Mg-trafficking between the cytosol and mitochondria. The AtMGT5 gene was exclusively expressed in anthers at early stages of flower development. Examination of two independent T-DNA insertional mutants of AtMGT5 gene demonstrated that AtMGT5 played an essential role for pollen development and male fertility. This study suggests a critical role for Mg2+ transport between cytosol and mitochondria in male gametogenesis in plants.