Transcriptome analyses give insights into selenium-stress responses and selenium tolerance mechanisms in Arabidopsis
Transcriptome analyses give insights into selenium-stress responses and selenium tolerance mechanisms in Arabidopsis
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DOI：
10.1111/j.1399-3054.2007.01002.x
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发表时间：
2008-02-08
影响因子：
6.4
通讯作者：
Pilon-Smits, Elizabeth A. H.
中科院分区：
文献类型：
--
作者：
Van Hoewyk, Doug;Takahashi, Hideki;Pilon-Smits, Elizabeth A. H.
硒酸盐的化学性质与硫酸盐相似，可以通过相同的转运蛋白和酶被植物吸收和同化。与许多其他生物体相比，硒 (Se) 尚未被证明对高等植物是必需的。过量的硒有毒并限制发育。硒缺乏和毒性都在世界范围内造成问题。为了更好地了解硒对植物代谢的影响以及涉及硒耐受性的植物机制，研究了在有或没有硒酸盐的情况下生长的拟南芥植物的转录组，并鉴定了硒响应基因。根和芽在基因调控和代谢方面表现出不同的与硒相关的变化。许多参与硫（S）吸收和同化的基因被上调。因此，硒处理提高了植物中硫酸盐的水平，但有机硫代谢物的数量减少了。 Se 也上调了调节乙烯和茉莉酸合成和信号传导的转录本。乙烯或茉莉酸反应途径缺陷的拟南芥突变体表现出对硒的耐受性降低，表明这两种应激激素在硒耐受性中发挥着重要作用。据报道，硒酸盐上调了多种转录本，这些转录本也是由盐和渗透压胁迫诱导的。硒酸盐似乎会抑制植物发育，正如细胞壁合成和生长素调节蛋白相关基因的下调所表明的那样。本研究中发现的硒响应基因可能有助于培育能够更好地耐受和积累硒的植物，这可能会增强硒植物修复的有效性或用作硒强化食品。
Selenate is chemically similar to sulfate and can be taken up and assimilated by plants via the same transporters and enzymes. In contrast to many other organisms, selenium (Se) has not been shown to be essential for higher plants. In excess, Se is toxic and restricts development. Both Se deficiency and toxicity pose problems worldwide. To obtain better insights into the effects of Se on plant metabolism and into plant mechanisms involved in Se tolerance, the transcriptome of Arabidopsis plants grown with or without selenate was studied and Se-responsive genes identified. Roots and shoots exhibited different Se-related changes in gene regulation and metabolism. Many genes involved in sulfur (S) uptake and assimilation were upregulated. Accordingly, Se treatment enhanced sulfate levels in plants, but the quantity of organic S metabolites decreased. Transcripts regulating the synthesis and signaling of ethylene and jasmonic acid were also upregulated by Se. Arabidopsis mutants defective in ethylene or jasmonate response pathways exhibited reduced tolerance to Se, suggesting an important role for these two stress hormones in Se tolerance. Selenate upregulated a variety of transcripts that were also reportedly induced by salt and osmotic stress. Selenate appeared to repress plant development, as suggested by the downregulation of genes involved in cell wall synthesis and auxin-regulated proteins. The Se-responsive genes discovered in this study may help create plants that can better tolerate and accumulate Se, which may enhance the effectiveness of Se phytoremediation or serve as Se-fortified food.