Glutathione imparts stress tolerance against <i>Alternaria brassicicola</i> infection via miRNA mediated gene regulation
收藏资源简介：
Glutathione (GSH) is well known to play a crucial role in imparting resistance against various pathogen invasions. Nevertheless, the role of GSH in regulating miRNA-mediated defense response is yet to be explored. To decipher the GSH-mediated regulation of miRNA expression during necrotrophic infection in <i>Arabidopsis thaliana</i>, wild-type Col-0 and <i>AtECS1</i>, the transgenic line exhibiting enhanced GSH content, were infected with necrotrophic pathogen <i>Alternaria brassicicola. AtECS1</i> plants exhibited enhanced resistance as compared to wild-type. MiRNA next-generation sequencing (NGS) was performed to compare the miRNA expression in Col-0 and <i>AtECS</i>1 leaves. Under control condition, differentially expressed 96 known miRNAs and 17 novel miRNAs viz. ath-miR8167f, ath-miR1886.3, ath-miR3932b-5p, etc. were identified. However, under infected condition, 73 known and 43 novel differentially expressed miRNAs viz. ath-miR5652, ath-miR160b, ath-miR865-5p, etc. were identified. Functional annotation and enrichment analysis revealed that several miRNAs that target defense-related genes like leucine-rich repeat protein kinase, MYB transcription factors, TCP8, etc. were down regulated in the <i>AtECS1</i> line, which, in turn, relieves the repression of their target gene expression, leading to resistance against infection. Together, the present investigation suggests that GSH plays a decisive role in modulating the miRNA-mediated regulation of defense-related genes during pathogen invasion.
谷胱甘肽（Glutathione, GSH）在抵御各类病原菌侵染过程中发挥关键作用，这一点已被广泛证实。然而，谷胱甘肽在调控miRNA介导的植物防御反应中的作用仍有待深入探究。 为解析拟南芥（Arabidopsis thaliana）在死体营养型病原菌侵染期间谷胱甘肽介导的miRNA表达调控机制，本研究以野生型Col-0以及谷胱甘肽含量提升的转基因株系AtECS1为实验材料，接种死体营养型病原菌芸苔链格孢（Alternaria brassicicola）。实验结果显示，相较于野生型植株，AtECS1株系的抗病性显著增强。 通过miRNA高通量测序（miRNA next-generation sequencing, NGS）对Col-0与AtECS1叶片中的miRNA表达谱进行比较分析。在正常培养（对照）条件下，共鉴定得到96个已知差异表达miRNA以及17个新型差异表达miRNA，包括ath-miR8167f、ath-miR1886.3、ath-miR3932b-5p等。 而在病原菌侵染条件下，共鉴定得到73个已知差异表达miRNA以及43个新型差异表达miRNA，包括ath-miR5652、ath-miR160b、ath-miR865-5p等。 功能注释与富集分析结果表明，AtECS1株系中多个靶向防御相关基因的miRNA呈现下调表达趋势，这些靶向防御基因包括富亮氨酸重复序列蛋白激酶、MYB转录因子、TCP8等；miRNA的下调表达会解除其对靶基因表达的抑制作用，进而增强植株对病原菌侵染的抗性。 综上，本研究证实谷胱甘肽在病原菌侵染过程中，通过调控miRNA介导的防御相关基因表达发挥决定性作用。
