大麦黄矮病毒侵染小麦miRNA鉴定和特征分析

大麦黄矮病毒(barley yellow dwarf viruses, BYDVs)引起的小麦黄矮病严重威胁我国麦类生产,造成严重经济损失。植物中的miRNA调控植物生长发育、信号转导及对外界压力的反应,通过调控植物抗性基因的表达影响植物与病原物的互作。本研究对感染BYDV-GAV后3 d、7 d及健康对照的‘小偃6号’小麦样品进行miRNA测序,合并去冗余后分别得到99、96、95个已知的miRNA序列和806、809、1 024个新miRNA序列。对这些miRNA进行差异表达分析,BYDV-GAV侵染后3 d和7 d的小麦样品,与对照相比上调表达的miRNA数量分别为3个和7个,下调表达的为14个和12个。将差异表达的miRNA利用psRNATarget进行靶基因预测,共得到1 254个靶标基因。靶基因的KEGG和GO富集分析,进一步明确了其功能及作用通路。对14个病毒病症状相关的靶基因进行定量分析,结果表明随病毒侵染时间的延长,这些靶基因出现差异性表达,显示miRNA参与了寄主与病毒的互作。研究结果有助于揭示BYDV-GAV与寄主小麦的互作机理。

Identification and characterization of miRNAs in wheat infected with barley yellow dwarf viruses

The wheat yellow dwarf disease caused by barley yellow dwarf viruses (BYDVs) seriously threatens the wheat production of China and causes huge economic losses to grain production.MicroRNAs (miRNAs) regulate plant growth and development,signal transduction and the response to external stresses,and affect plant-pathogen interactions by regulating plant resistance genes.In our study,miRNA sequencing was performed on wheat samples at 0 d,3 d,and 7 d infected by BYDV-GAV.As a result,99,96 and 95 known miRNAs after merging and eliminating the redundant miRNAs,whereas 806,809 and 1024 new miRNA sequences were obtained,respectively.Differential expression analysis of these miRNAs showed that the number of miRNAs up-regulated in BYDV-GAV-infected wheat samples at 3 d and 7 d was 3 and 7 respectively,and the down-regulated expression was 14 and 12 compared with the mock samples.Subsequently,1254 target genes were predicted by psRNATarget.The KEGG and GO enrichment analysis of target genes further clarified their functions and pathways.Quantitative analysis of 14 target genes related to viral disease symptoms revealed that these target genes were differentially expressed with change in days post viral infection,indicating that miRNAs are involved in the interaction between host and virus.This study laid a foundation for revealing the interaction mechanism between BYDV-GAV and host wheat plant.