RESUMO
Objective: To provide a good start for the study of miRNA in Astragalus membranaceus, the miRNAs and their targets were predicted using bioinformatics approach, then the drought-induced expression pattern was analyzed using quantitative RT-PCR. Methods: The deep sequencing data downloaded from public database were assembled using Trinity to establish the transcriptome database. Bioinformatics method was employed to predict miRNAs and their targets, functional classification analyses of targets were conducted. Stem-loop fluorescence quantitative PCR method was used to validate miRNAs, and the drought-induced expression patterns of miRNA were also determined. Results: A transcriptome database with 88 263 sequences was obtained. Based on the transcriptomic sequences, 17 miRNA, classified into 17 families, generated from 17 stem-loop precursors, were identified. A total of 145 genes were predicted to be regulated by these miRNAs, and these genes were involved into diversified biological processes including gene transcription regulation, substance metabolism, signal transduction, stress response, and post translational modification of protein. Eight miRNAs were randomly selected for expression analysis and the results indicated that miR2118 and miR166 might be involved in drought stress response. Conclusion: The miRNAs, the corresponding targets and the drought response miRNAs identified in this study will provide a solid basis for understanding the biological functions of miRNAs in A. membranaceus.
