Neller Kira C M, Klenov Alexander, Guzman Juan C, Hudak Katalin A
Department of Biology, York University, Toronto, ON, Canada.
Department of Electrical Engineering and Computer Science, York University, Toronto, ON, Canada.
Front Plant Sci. 2018 May 3;9:589. doi: 10.3389/fpls.2018.00589. eCollection 2018.
The American pokeweed plant, , displays broad-spectrum resistance to plant viruses and is a heavy metal hyperaccumulator. However, little is known about the regulation of biotic and abiotic stress responses in this non-model plant. To investigate the control of miRNAs in gene expression, we sequenced the small RNA transcriptome of pokeweed treated with jasmonic acid (JA), a hormone that mediates pathogen defense and stress tolerance. We predicted 145 miRNAs responsive to JA, most of which were unique to pokeweed. These miRNAs were low in abundance and condition-specific, with discrete expression change. Integration of paired mRNA-Seq expression data enabled us to identify correlated, novel JA-responsive targets that mediate hormone biosynthesis, signal transduction, and pathogen defense. The expression of approximately half the pairs was positively correlated, an uncommon finding that we functionally validated by mRNA cleavage. Importantly, we report that a pokeweed-specific miRNA targets the transcript of , novel evidence that a miRNA regulates a JA biosynthesis enzyme. This first large-scale small RNA study of a Phytolaccaceae family member shows that miRNA-mediated control is a significant component of the JA response, associated with widespread changes in expression of genes required for stress adaptation.
美国商陆植物对植物病毒具有广谱抗性，并且是一种重金属超积累植物。然而，对于这种非模式植物中生物和非生物胁迫响应的调控知之甚少。为了研究微小RNA（miRNA）对基因表达的调控，我们对用茉莉酸（JA）处理的商陆小RNA转录组进行了测序，茉莉酸是一种介导病原体防御和胁迫耐受性的激素。我们预测了145个对JA有响应的miRNA，其中大多数是商陆特有的。这些miRNA丰度较低且具有条件特异性，表达变化离散。配对的mRNA测序表达数据的整合使我们能够鉴定出介导激素生物合成、信号转导和病原体防御的相关的、新的JA响应靶标。大约一半的配对表达呈正相关，这一不常见的发现我们通过mRNA切割进行了功能验证。重要的是，我们报道了一种商陆特有的miRNA靶向[具体基因名称未给出]的转录本，这是miRNA调控JA生物合成酶的新证据。这项对商陆科家族成员的首次大规模小RNA研究表明，miRNA介导的调控是JA响应的重要组成部分，与胁迫适应所需基因表达的广泛变化相关。
