Roles of the transcriptional regulation mediated by the nitrate-responsive cis-element in higher plants
Roles of the transcriptional regulation mediated by the nitrate-responsive cis-element in higher plants
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DOI：
10.1016/j.bbrc.2011.07.008
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发表时间：
2011-08-12
影响因子：
3.1
通讯作者：
Yanagisawa, Shuichi
中科院分区：
文献类型：
--
作者：
Konishi, Mineko;Yanagisawa, Shuichi
硝酸盐是陆地植物的主要氮源，同时也是调节基因表达、代谢和植物生长的信号分子。硝酸盐还原酶（NR）和亚硝酸盐还原酶（NIR）基因是硝酸盐同化途径中的酶，是典型的硝酸盐诱导基因。我们之前通过分析拟南芥的 NIR 基因启动子，鉴定了第一个用于硝酸盐诱导转录的真实硝酸盐响应顺式元件 (NRE)。在这里，我们使用转基因拟南芥植物进一步描述了 NRE 介导的调节。第一的。 NRE 介导的调节被证明是对由预先存在的成分引起的硝酸盐的主要反应，因为 NRE 介导的 GUS 报告基因的硝酸盐诱导表达不受蛋白质合成抑制剂放线菌酮处理的影响。其次，我们发现 NRE 样序列存在于各种双子叶和单子叶 NIR 基因启动子中的相似位置，并且它们也在拟南芥中驱动硝酸盐诱导型表达。这表明 NRE 介导的调节在高等植物中可能是保守的。最后，NRE 介导的 GUS 报告基因表达在转基因拟南芥植物中产生昼间表达。这种表达在一天开始时达到峰值，并在白天下降，这与报道的硝酸盐含量的昼夜模式非常相似，表明 NRE 介导的调节在控制昼夜表达中的作用，以响应昼夜循环中硝酸盐含量的波动。这些发现进一步阐明了高等植物中 NRE 介导的调节系统的作用。 (C) 2011 Elsevier Inc. 保留所有权利。
Nitrate is a major nitrogen source for land plants but also acts as a signaling molecule that regulates gene expression, metabolism and plant growth. The genes for nitrate reductase (NR) and nitrite reductase (NIR), which are enzymes in the nitrate assimilation pathway, are typical nitrate-inducible genes. We previously identified the first authentic nitrate-responsive cis-element (NRE) for nitrate-inducible transcription by the analysis of the NIR gene promoter from Arabidopsis. Here we further characterize NRE-mediated regulation using transgenic Arabidopsis plants. First. NRE-mediated regulation is shown to be a primary response to nitrate that is caused by pre-existing components, because the NRE-mediated nitrate-inducible expression of the GUS reporter gene is unaffected by treatment with the protein synthesis inhibitor cycloheximide. Second, we show that NRE-like sequences are present in various dicotyledonous and monocotyledonous NIR gene promoters at similar positions and that they also drive nitrate-inducible expression in Arabidopsis. This suggests that NRE-mediated regulation might be conserved in higher plants. Finally, the NRE-mediated expression of the GUS reporter gene is shown to produce diurnal expression in transgenic Arabidopsis plants. This expression peaked at the beginning of the day and decreased during the day which is very similar to the reported diurnal pattern of the nitrate content, suggesting a role of NRE-mediated regulation in controlling diurnal expression in response to oscillation of the nitrate content over a day/night cycle. These findings further clarify the roles of the NRE-mediated regulatory system in higher plants. (C) 2011 Elsevier Inc. All rights reserved.