TaEIL1, a wheat homologue of AtEIN3, acts as a negative regulator in the wheat-stripe rust fungus interaction
TaEIL1, a wheat homologue of AtEIN3, acts as a negative regulator in the wheat-stripe rust fungus interaction
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TaEIL1 是 AtEIN3 的小麦同源物，在小麦-条锈菌相互作用中充当负调节因子
DOI：
10.1111/mpp.12044
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发表时间：
2013-09-01
影响因子：
4.9
通讯作者：
Kang, Zhensheng
中科院分区：
文献类型：
--
作者：
Duan, Xiaoyuan;Wang, Xiaojie;Kang, Zhensheng
转录因子在植物发育和防御反应的转录调控中起着至关重要的作用。越来越多的证据表明，EIN3参与植物对病原体感染和环境刺激的防御反应。然而，EIN3在小麦抗小麦锈病（Pst）中的作用尚不清楚。本研究基于小麦- pst互作cDNA文库中的序列片段，通过cDNA末端快速扩增（RACE）分离出TaEIL1。TaEIL1蛋白含有典型的ein3结合结构域，瞬时表达分析表明TaEIL1定位于细胞核。酵母单杂交实验表明，TaEIL1具有转录活性，其c端是激活转录所必需的。TaEIL1转录本受环境应激刺激调控，在水杨酸（SA）处理下转录本减少。当小麦叶片受Pst胁迫时，亲和互作中TaEIL1的转录量约为不亲和互作的3倍。通过大麦条纹花叶病毒（BSMV）病毒诱导的基因沉默（VIGS）系统敲除TaEIL1使Pst的生长减弱，菌丝缩短，菌丝分枝减少，吸器母细胞减少，菌落大小减小。此外，Pst无毒小种CYR23引发坏死加剧，表明在taeil1沉默的小麦植株中，超敏反应得到加强。因此，防御相关基因的上调和蔗糖丰度的增加可能有助于增强小麦对CYR31的抗病能力。综上所述，抑制TaEIL1转录本可以增强小麦对条锈病的抗性。
Transcription factors (TFs) play crucial roles in the transcriptional regulation of plant development and defence responses. Increasing evidence has implicated ETHYLENE INSENSITIVE3 (EIN3) in the plant defence response to pathogen infection and environmental stimuli. However, the role of EIN3 in wheat resistance to Puccinia striiformis f. sp. tritici (Pst) is not clear. Here, TaEIL1 was isolated by rapid amplification of cDNA ends (RACE) based on a sequence fragment from a wheat-Pst interaction cDNA library. The TaEIL1 protein contains a typical EIN3-binding domain, and transient expression analyses indicated that TaEIL1 is localized in the nucleus. Yeast one-hybrid assay revealed that TaEIL1 exhibits transcriptional activity, and its C-terminus is necessary for the activation of transcription. TaEIL1 transcripts were regulated by environmental stress stimuli and were decreased under salicylic acid (SA) treatment. When wheat leaves were challenged with Pst, the transcript level of TaEIL1 in the compatible interaction was approximately three times higher than that in the incompatible interaction. Knocking down TaEIL1 through the Barley stripe mosaic virus (BSMV) virus-induced gene silencing (VIGS) system attenuated the growth of Pst, with shortened hyphae and reduced hyphal branches, haustorial mother cells and colony size. Moreover, enhanced necrosis was triggered by the Pst avirulent race CYR23, indicating that the hypersensitive response was strengthened in TaEIL1-silenced wheat plants. Thus, the up-regulation of defence-related genes and increased sucrose abundance might contribute to the enhanced disease resistance of wheat to the virulent race CYR31. Taken together, the results suggested that the suppression of TaEIL1 transcripts could enhance the resistance of wheat to stripe rust fungus.