PDF(Pubmed)
Abstract：
Excessive reactive oxygen species stress due to salinity poses a significant threat to the growth of Glycyrrhiza uralensis Fisch. To adapt to salt stress, G. uralensis engages in alternative splicing (AS) to generate a variety of proteins that help it withstand the effects of salt stress. While several studies have investigated the impact of alternative splicing on plants stress responses, the mechanisms by which AS interacts with transcriptional regulation to modulate the salt stress response in G. uralensis remain poorly understood. In this study, we utilized high-throughput RNA sequencing data to perform a comprehensive analysis of AS events at various time points in G. uralensis under salt stress, with exon skipping (SE) being the predominant AS type. KEGG enrichment analysis was performed on the different splicing genes (DSG), and pathways associated with AS were significantly enriched, including RNA transport, mRNA surveillance, and spliceosome. This indicated splicing regulation of genes, resulting in AS events under salt stress conditions. Moreover, plant response to salt stress pathways were also enriched, such as mitogen-activated protein kinase signaling pathway - plant, flavonoid biosynthesis, and oxidative phosphorylation. We focused on four differentially significant genes in the MAPK pathway by AS and qRT-PCR analysis. The alternative splicing type of MPK4 and SnRK2 was skipped exon (SE). ETR2 and RbohD were retained intron (RI) and alternative 5\'splice site (A5SS), respectively. The expression levels of isoform1 of these four genes displayed different but significant increases in different tissue sites and salt stress treatment times. These findings suggest that MPK4, SnRK2, ETR2, and RbohD in G. uralensis activate the expression of isoform1, leading to the production of more isoform1 protein and thereby enhancing resistance to salt stress. These findings suggest that salt-responsive AS directly and indirectly governs G. uralensis salt response. Further investigations into AS function and mechanism during abiotic stresses may offer novel references for bolstering plant stress tolerance.
摘要：
盐度引起的过度活性氧胁迫对甘草的生长构成重大威胁。为了适应盐压力，G.uralensis参与可变剪接（AS）以产生各种蛋白质，帮助其承受盐胁迫的影响。虽然一些研究已经调查了可变剪接对植物胁迫反应的影响，AS与转录调节相互作用以调节G.uralensis的盐应激反应的机制仍然知之甚少。在这项研究中,我们利用高通量RNA测序数据对盐胁迫下的uralensis中不同时间点的AS事件进行了综合分析，外显子跳跃（SE）是主要的AS类型。对不同剪接基因（DSG）进行KEGG富集分析，与AS相关的通路显著丰富，包括RNA转运，mRNA监测，和剪接体。这表明基因的剪接调控，导致盐胁迫条件下的AS事件。此外，植物对盐胁迫的反应途径也得到了丰富，如丝裂原活化蛋白激酶信号通路-植物，类黄酮生物合成，和氧化磷酸化。我们通过AS和qRT-PCR分析重点研究了MAPK途径中的四个差异显著基因。MPK4和SnRK2的选择性剪接类型被跳过外显子(SE)。ETR2和RbohD保留了内含子（RI）和5'选择性剪接位点（A5SS），分别。这四个基因的isoform1的表达水平在不同的组织部位和盐胁迫处理时间显示出不同但显着的增加。这些发现表明，uralensis中的MPK4，SnRK2，ETR2和RbohD激活了isoform1的表达，导致产生更多的isoform1蛋白，从而增强了对盐胁迫的抵抗力。这些发现表明，盐响应性AS直接和间接地控制着乌拉尔草的盐响应。对非生物胁迫期间AS功能和机制的进一步研究可能为增强植物胁迫耐受性提供新的参考。
