Magnesium uptake characteristics in Arabidopsis revealed by 28Mg tracer studies
Magnesium uptake characteristics in Arabidopsis revealed by 28Mg tracer studies
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DOI：
10.1007/s00425-018-2936-4
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发表时间：
2018-06
期刊：
影响因子：
4.3
通讯作者：
Takaaki Ogura;N. Kobayashi;H. Suzuki;R. Iwata;T. Nakanishi;K. Tanoi
中科院分区：
文献类型：
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作者：
Takaaki Ogura;N. Kobayashi;H. Suzuki;R. Iwata;T. Nakanishi;K. Tanoi
主要结论拟南芥根中的 Mg2+ 吸收系统对 Gd3+- 和 Fe2+ 敏感，并在 AtMRS2 转运蛋白的参与下对 1 小时内变化的 Mg2+ 浓度做出响应。摘要镁 (Mg2+) 吸收及其活性调节机制尚未阐明。为了解决这些问题，有必要揭示根部吸收Mg2+的特征。因此，我们首先利用28Mg研究了1周龄拟南芥植物根部对Mg2+的吸收特性。响应低 Mg2+ 条件，根部 Mg2+ 吸收系统在 1 小时内上调。这种诱导在拟南芥“线粒体RNA剪接2/镁转运”突变体atmrs2-4/atmgt6和atmrs2-7/atmgt7中受到抑制，而拟南芥野生型中AtMRS2-4/AtMGT6和AtMRS2-7/AtMGT7基因的表达对Mg2+条件没有反应。此外，当 Mg2+ 重新供应到环境中时，缺镁引起的 Mg2+ 吸收系统会在 5 分钟内关闭。抑制研究表明，在 Mg2+ 充足的条件下，Mg2+ 吸收的本构机制对许多二价和三价阳离子敏感，特别是 Gd3+ 和 Fe2+，但对 K+ 不敏感。
Main conclusionThe Mg2+uptake system in Arabidopsis roots is Gd3+- and Fe2+-sensitive, and responds to a changing Mg2+concentration within 1 h with the participation of AtMRS2 transporters.AbstractMagnesium (Mg2+) absorption and the mechanism regulating its activity have not been clarified yet. To address these issues, it is necessary to reveal the characteristics of Mg2+uptake in roots. Therefore, we first investigated the Mg2+uptake characteristics in roots of 1-week-old Arabidopsis plants using28Mg. The Mg2+uptake system in roots was up-regulated within 1 h in response to the low Mg2+condition. This induction was inhibited in Arabidopsis “mitochondrial RNA splicing 2/magnesium transport” mutantsatmrs2-4/atmgt6andatmrs2-7/atmgt7, while the expression ofAtMRS2-4/AtMGT6andAtMRS2-7/AtMGT7genes in the Arabidopsis wild-type was not responsive to Mg2+conditions. In addition, the Mg deficiency-induced Mg2+uptake system was shut-down within 5 min when Mg2+was resupplied to the environment. An inhibition study showed that the constitutive mechanism functioning in Mg2+uptake under Mg2+sufficient conditions was sensitive to a number of divalent and trivalent cations, particularly Gd3+and Fe2+, but not to K+.