油菜盐胁迫响应miRNA及其靶基因鉴定

Identification of miRNAs and their target genes in response to salt stress in Brassica napus

油菜是世界上重要的油料作物之一,然而土壤盐胁迫严重抑制油菜的生长发育和籽粒产量。前人研究表明,在盐胁迫下,植物通过表达一些miRNA,并调控其靶基因的表达,进而提高植物自身的盐胁迫抗性。本研究分别在200 mmol·L^(-1) NaCl处理(T)和对照(C)条件下培养油菜,取其地上部(S)和根(R)构建了12个小RNA文库进行高通量测序。通过对全基因组的miRNA进行差异表达分析,一共鉴定到了26个差异表达的miRNA,并预测了171个相应的靶基因。结合前期转录组的基因差异表达以及本研究的miRNA差异表达结果,推测miRNA156-SPL15-WRKY、miRNA397-LAC12-木质素、miR169-NFYA5和miR399-UBC29-泛素化等通路可能参与了油菜盐胁迫抗性调控。本研究所鉴定的miRNA及其核心靶基因丰富了油菜盐胁迫抗性的表观调控机制,并为油菜盐胁迫抗性的遗传改良提供了优异的基因资源。

Brassica napusL. is one of the important oil crops in the world. However soil salt stress severely inhibited its growth and development. Previous studies have shown that under salt stress, plants increase their own salt stress resistance by expressing some miRNAs and regulating the expression of their target genes. In this study,rapeseed was cultured under 200 mmol·L^(-1)NaCl treatment and control, and took the shoot and root to construct 12 small RNA libraries for high-throughput sequencing. Through the differential expression analysis of miRNAs in the whole genome, a total of 26 differentially expressed miRNAs were identified and 171 corresponding target genes were predicted. Combining the differential expression of genes in the early transcriptome and the results of the differential expression of miRNAs in this study, it is speculated that miRNA156-SPL15-WRKY, miRNA397-LAC12-xylogen, miR169-NFYA5 and miR399-UBC29-ubiquitination pathways might be involved in the regulation of salt stress resistance in B. napus.