鸭茅响应水淹胁迫的miRNA差异表达分析

水淹胁迫是限制我国西南地区鸭茅产量和品质提升的主要环境因子，已经成为一种不容忽视的非生物胁迫。鉴定鸭茅耐涝相关的功能基因，并探究其调控机制是鸭茅种质创新，提高鸭茅耐涝能力的必要途径。以鸭茅耐涝品种“滇北”为试验材料，分别经水淹胁迫处理0、8和24 h后，利用Illumina Hiseq测序平台对鸭茅叶片进行小RNA测序。结果表明，在水淹胁迫处理下共鉴定得到208个差异表达基因（DEGs），经过筛选后有38个基因上调表达，34个基因下调表达，共占差异表达基因的34.62%。“滇北”鸭茅在水淹胁迫下差异表达基因主要属于miR166、miR167、miR159、miR396和miR156这5个miRNA基因家族。基于对差异miRNA进行靶基因预测及靶基因的GO和KEGG功能分析，发现这些靶基因主要参与细胞生理过程、代谢过程、IL-17信号通路、Th17细胞分化等植物逆境响应过程，为进一步揭示鸭茅在水淹胁迫下的分子调控机制提供了研究线索。

A differential gene expression analysis of miRNA in Dactylis glomerata in response to flooding stress

Waterlogging stress is the main environmental factor that restricts the improvement of yield and quality of orchard grass （Dactylis glomerata） in Southwest China， and it has become a category of abiotic stress that can’t be ignored， from a research perspective. This research aimed to identify functional genes related to waterlogging tolerance of orchard grass， and explore its regulation mechanisms， as a means of improving the waterlogging tolerance of this grass. In this research， the waterlogging tolerant variety “Dian bei” was studied. After being subjected to flooding stress for 0， 8 and 24 h， RNA was extracted from orchard grass leaves and sequencing was carried out using an Illumina Hiseq sequencing platform. A total of 208 differentially expressed genes were identified under flooding stress， 38 genes were up-regulated and 34 genes were down-regulated， accounting for 34.62% of the differentially expressed genes （DEGs）. The genes identified as differentially in “Dian bei” orchard grass under flooding stress mainly belong to five miRNA gene families： miR166， miR167， miR159， miR396 and miR156. Based on the predicted function of target genes of differentially expressed miRNA and functional analysis using GO（gene ontology） and KEGG （kyoto encyclopedia of genes and genomes） of target genes， it was determined that the identified DEGs were mainly involved in plant stress response processes， such as cellular processes， metabolic processes， the IL-17 signaling pathway， Th17 cell differentiation， and others. These results provide initial direction for further study of the molecular regulation and response mechanisms of orchard grass under flooding stress.