图1 小麦中miRNA和其靶基因组成的调控网络

小麦条锈病，由小麦条锈菌（Pst）引起，是全球范围内对小麦最具破坏性的疾病之一。miRNA是重要的调控元件，在植物器官发育，蔬菜相变，以及防御反应中发挥非常关键的作用。在本项研究中，西北农林科技大学旱区作物逆境生物学国家重点实验室康振生教授和王晓杰教授领衔的课题组系统探讨了miRNA在小麦抗条锈菌侵染中的作用。

课题组选用小麦品种Xingzi 9104（XZ），分别构建无毒性Pst种CYR32处理的和无菌水处理的miRNA文库，并进行测序分析（小RNA测序数据分析由联川生物承担完成）。测序共获得了596个miRNA候选者。研究人员使用微阵列在Pst处理的成年植株上对420个小麦特异的miRNA候选者进行了筛查。分析了候选miRNA的丰度，并使用qRT-PCR对一组候选miRNAs的表达水平进行测定。qRT-PCR结果表明，一些miRNA参与了小麦和Pst间不相容的互作。此外，研究人员鉴定出一些miRNAs在不同的叶片中存在差异表达。研究人员进一步采用降解组测序技术对小麦miRNA的靶基因进行了确认（降解组测序项目由联川生物承担完成）。发现大部分被注释的靶基因与信号转导，能量代谢，以及其他功能有关。研究人员对选定的一些靶基因，使用qRT-PCR进行了相对表达量分析，发现RabGAP/TBC结构域蛋白，锌指蛋白和富含半胱氨酸的类受体蛋白激酶41可能在XZ和CYR32间不相容的互作中发挥重要的作用。有趣的是，miRNA与靶基因似乎构成了一个复杂的调控网络，调节小麦和Pst的互作。

此项研究数据为评估miRNA在小麦和Pst互作中的重要调控作用奠定了基础。（来源：生物通）

Exploration of microRNAs and their targets engaging in the resistance interaction between wheat and stripe rust

Abstract  Wheat stripe rust, caused by Puccinia striiformis f. sp. tritici (Pst), is one of the most destructive diseases of wheat worldwide. miRNAs are important regulators, they play very central roles in plant organ development, vegetable phase change and defense responses. In this study, two miRNA libraries from wheat cultivar Xingzi 9104 (XZ) challenged with the avirulent Pst race CYR32 and sterile water were constructed, respectively. A total of 596 miRNA candidates were obtained. 420 wheat-specific candidate miRNAs were screened in adult plants challenged with Pst using microarray-based analyses. We analyzed the abundance of candidate miRNAs, and the levels of a subset of candidate miRNAs were determined by quantitative real time PCR (qRT-PCR). The qRT-PCR results indicated that some miRNAs were involved in the incompatible interaction between wheat and Pst. In addition, we identified some miRNAs differentially expressed in different leaves. Additionally, the target genes of wheat miRNAs were confirmed by using degradome sequencing technology. Most of the annotated target genes are related to signal transduction, energy metabolism, and other functions. We selected some target genes for relative expression analysis using qRT-PCR, and found that RabGAP/TBC domain-containing protein, zinc finger protein and Cysteine-rich receptor-like protein kinase 41 may play important role in the incompatible interaction between XZ and CYR32. Intriguingly, miRNAs and target gene seem to form a complicated regulation network that regulates the wheat-Pst interaction. Our data provide the foundation for evaluating the important regulatory roles of miRNAs in the wheat-Pst interaction.

原文链接：http://journal.frontiersin.org/article/10.3389/fpls.2015.00469/full