油菜苗期低温胁迫响应miRNA的鉴定及其靶基因预测分析OA

Low temperature stress severely influence the geographical distribution,growth and development,yield,and quality of rapeseed.In this study,to explore miRNAs response to low temperature and their target genes,elucidate the regulatory mechanism of resistance to low temperature stress in rapeseed,we used cold resistant rape-seed seedling leaves subjected to 6 hours of-3℃ stress and room temperature as material,constructed miRNA li-braries for high-throughput sequencing and bioinformatics analysis.A total of 76 known miRNAs and 200 novel miRNAs were identified,with 11 differentially expressed miRNAs,of which 5 were up-regulated and 6 down-regu-lated,and 618 corresponding target genes were predicted.GO analysis showed that the target genes were highly en-riched in regulation of COPI vesicle coat,intracellular protein transport,and transporter activity items in the three categories of cell component,biological process,and molecular function,respectively.KEGG analysis indicated that target genes have been enriched in endocytosis,RNA transport and amino sugar and nucleotide sugar metabolism.The qRT-PCR validation of differentially expressed miRNAs and their target genes showed that the five miRNAs exhibited negative regulatory relationships with their target genes.As a result,miRNAs in rapeseed can respond to low temperature stress by negatively regulating target genes,which can provide miRNAs and candidate target genes for the study of low-temperature stress mechanisms in rapeseed.