Molecular Characterization of miRNAs in Carrying Brassica Yellows Virus.

microRNAs (miRNAs) influence many biological processes at the post-transcriptional level. However, the molecular characterization of miRNAs in the response to Brassica yellows virus (BrYV) stress remains unclear. In this study, we present the results of miRNA profiling in under two different treatments: treatment one (raised on turnip plants), and treatment two (raised on ). A total of 72 known and 113 novel mature miRNAs were identified in both non-viruliferous and viruliferous aphids, under treatment one. In treatment two, 72 known and 112 novel mature miRNAs were identified in BrYV-free aphids; meanwhile, 71 known and 115 novel miRNAs were identified in BrYV-carrying aphids. Moreover, eight upregulated and four downregulated miRNAs were identified in viruliferous aphids under treatment two, whereas only two miRNAs were differentially expressed under treatment one. These results indicated the relative BrYV level could influence miRNA expression in aphids. KEGG enrichment analysis showed the predicted genes targeted by differentially expressed miRNAs were primarily involved in Peroxisome, neuroactive ligand-receptor interaction, and metabolism of xenobiotics by cytochrome P450 pathways. Taken together, these findings reveal the effect of BrYV on miRNAs in and provide key clues for further studies on the molecular mechanisms of BrYV transmission via aphids.