Identification and characterization of conserved microRNAs in Rheum ribes root

MicroRNAs (miRNAs) are a group of short non-coding RNA molecules with a length of about 18-24 nucleotides, which control target genes expression at the post-transcriptional level. There are no reports of miRNA detection in Rheum ribes plant. Therefore, in the present study, in order to predict potential conserved miRNAs and their target genes in R.ribes roots, total RNA was extracted from the root tissue and sequenced. Then, non-coding transcripts were identified in R.ribes transcriptome and considered as miRNA precursor candidate sequences. In this study, 82047 transcripts were created from R.ribes root by de novo assembly method. By searching the homology of these transcripts with mirbas database and secondary structure prediction, 4 conserved miRNAs belonging to mir396, mir164, mir319 and mir168 families were identified. 574 transcripts from R.ribes root transcriptome were targeted by these miRNAs. In general, due to the regulatory role of identified miRNAs on a wide range of genes, these miRNAs can be used to identify genes related to secondary metabolites.