Centre for Applied Geosciences, Geomicrobiology, University of Tuebingen, Sigwartstrasse 10, 72076, Tuebingen, Germany.
Plant Mol Biol. 2014 Jun;85(3):301-16. doi: 10.1007/s11103-014-0186-9. Epub 2014 Apr 12.
Rice is one of the most important staple foods worldwide, but it often contains inorganic arsenic, which is toxic and gives rise to severe health problems. Rice plants take up arsenate As(V) via the phosphate transport pathways, though it is not known how As(V), as compared to phosphate, modifies the expression of phosphate transporters (PTs). Therefore, the impact of As(V) or phosphate (Pi) on the gene expression of PTs and several Pi signaling regulators was investigated. Rice plants were grown on medium containing different As(V) or Pi concentrations. Growth was evaluated and the expression of tested genes was quantified at different time points, using quantitative RT-PCR (qPCR). The As and P content in plants was determined using inductively coupled plasma mass spectrometry (ICP-MS). As(V) elicited diverse and opposite responses of different PTs in roots and shoots, while Pi triggered a more shallow and uniform transcriptional response in several tested genes. Only a restricted set of genes, including PT2, PT3, PT5 and PT13 and two SPX-MFS family members, was particularly responsive to As(V). Despite some common reactions, the responses of the analyzed genes were predominantly ion-specific. The possible reasons and consequences are discussed.
水稻是全球最重要的主食之一，但它常含有无机砷，这是一种有毒物质，会引发严重的健康问题。水稻通过磷酸盐转运途径摄取砷酸盐 As(V)，但目前尚不清楚 As(V)与磷酸盐相比如何修饰磷酸盐转运蛋白 (PT) 的表达。因此，研究了 As(V)或磷酸盐 (Pi) 对 PTs 和几种 Pi 信号调节剂基因表达的影响。将水稻种植在含有不同 As(V)或 Pi 浓度的培养基上。使用定量 RT-PCR (qPCR) 在不同时间点评估生长并定量测试基因的表达。使用电感耦合等离子体质谱 (ICP-MS) 测定植物中的 As 和 P 含量。As(V)在根和茎中引发不同 PT 的不同和相反的反应，而 Pi 在几个测试基因中引发更浅和更均匀的转录反应。只有一组受限制的基因，包括 PT2、PT3、PT5 和 PT13 以及两个 SPX-MFS 家族成员，对 As(V)特别敏感。尽管存在一些共同反应，但分析基因的反应主要是离子特异性的。讨论了可能的原因和后果。
