STOP1 regulates the expression of HsfA2 and GDHs that are critical for low-oxygen tolerance in Arabidopsis
STOP1 regulates the expression of HsfA2 and GDHs that are critical for low-oxygen tolerance in Arabidopsis
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DOI：
10.1093/jxb/erz124
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发表时间：
2019-06-01
影响因子：
6.9
通讯作者：
Koyama, Hiroyuki
中科院分区：
文献类型：
--
作者：
Enomoto, Takuo;Tokizawa, Mutsutomo;Koyama, Hiroyuki
STOP1 （SENSITIVE TO PROTON RHIZOTOXICITY 1）转录因子调控植物根系中与多重胁迫耐受相关的基因表达。在这项研究中，我们研究了拟南芥中stop1突变体对低氧胁迫敏感的机制。转录组学分析显示，与低氧耐量有关的两个基因，即谷氨酸脱氢酶1 （GDH1）和GDH2，在stop1突变体中的表达水平低于野生型。gdh1gdh2双突变体对低氧条件的敏感性部分归因于stop1突变体的低氧敏感性。两种转录因子STOP2和热休克因子A2 （HsfA2）在stop1突变体中的表达水平较低。植物内互补实验表明，CaMV35S::STOP2或CaMV35S::HsfA2部分恢复了stop1突变体的低氧耐受性，同时恢复了调节低ph耐受性的基因和编码分子伴侣的基因的表达。顺式元件预测和植物启动子分析显示，STOP1直接激活HsfA2的表达。烟草中也检测到类似的依赖于stop1的低氧敏感性。抑制NtSTOP1诱导低氧敏感性，与野生型相比，NtHsfA2和NtGDHs的表达水平较低。结果表明，STOP1通过转录调控多向调控低氧耐受性。
The SENSITIVE TO PROTON RHIZOTOXICITY 1 (STOP1) transcription factor regulates gene expression associated with multiple stress tolerances in plant roots. In this study, we investigated the mechanism responsible for the sensitivity of the stop1 mutant to low-oxygen stress in Arabidopsis. Transcriptomic analyses revealed that two genes involved in low-oxygen tolerance, namely GLUTAMATE DEHYDROGENASE 1 (GDH1) and GDH2, showed lower expression levels in the stop1 mutant than in the wild-type. Sensitivity of the gdh1gdh2 double-mutant to low-oxygen conditions was partly attributable to the low-oxygen sensitivity of the stop1 mutant. Two transcription factors, STOP2 and HEAT SHOCK FACTOR A2 (HsfA2), were expressed at lower levels in the stop1 mutant. An in planta complementation assay indicated that CaMV35S::STOP2 or CaMV35S::HsfA2 partially rescued the low-oxygen tolerance of the stop1 mutant, which was concomitant with recovered expression of genes regulating low-pH tolerance and genes encoding molecular chaperones. Prediction of cis-elements and in planta promoter assays revealed that STOP1 directly activated the expression of HsfA2. Similar STOP1-dependent low-oxygen sensitivity was detected in tobacco. Suppression of NtSTOP1 induced low-oxygen sensitivity, which was associated with lower expression levels of NtHsfA2 and NtGDHs compared with the wild-type. Our results indicated that STOP1 pleiotropically regulates low-oxygen tolerance by transcriptional regulation.