目的 利用生物信息学手段预测甘草Glycyrrhiza uralensis 的microRNA（miRNA），并实验验证其存在，确定相应的靶基因，为理解甘草miRNA的生物学功能奠定基础。方法 下载公共核酸数据库中的甘草高通量测序序列和表达序列、标签序列，使用Trinity和Assembler等软件拼接以获得转录本数据。基于miRNA前体序列在植物物种间的保守性，将miRBase数据库中的已知植物miRNA前体与甘草转录组序列进行Blast比对，按照miRNA前体应具备的标准进行筛选。通过stem-loop qRT-PCR实验验证miRNA。使用psRNATarget软件进行miRNA的靶基因预测，并对靶基因进行功能分析。结果 序列拼接获得88 263条甘草转录组数据。使用这些数据预测到分属于17个家族的49个miRNA序列，以及相应的30个茎环结构前体，随机选取其中12个，经实验验证，确实存在。这些miRNA靶向的172个基因主要参与基因转录调控、信号转导、发育调控和防御反应等生物学过程。结论 新预测的甘草miRNA及其靶基因为进一步研究miRNA在甘草中的生物学功能奠定了基础。

Objective To provide a good start for understanding the roles of micoRNA in Glycyrrhiza uralensis, the microRNAs and their target genes were predicted using bioinformatic approach. Methods The deep sequencing data and EST sequences downloaded from public database were assembled using the Trinity and Assembler softwares to establish the transcriptome database. Since most of the plant miRNAs were conserved in plant species, all plant miRNAs stem-loop precursors were aligned to the assembled transcriptome database and the putative miRNA precursors were identified according to a rigorous criterion. psRNATarget was employed to predicted the targets of miRNA. Results A general transcriptome database with 88 and 263 sequences was obtained. Based on the transcriptomic sequences, 49 miRNA, classified into 17 families, arising from 30 stem-loop precursors, were identified. A total of 172 genes were predicted to be regulated by these miRNA, and these genes were involved into diversified biological processes including gene transcription regulation, signal transduction, development regulation, and defense response. Conclusion The miRNAs and the corresponding target genes identified in this study will provide a solid basis for understanding their biological functions in G. uralensis.

国家自然科学基金资助（31370356）；中央民族大学学术团队建设项目（2015C8）；国家大学生创新创业训练计划（GCCX2014110045）