Deep Sequencing Identifies Tissue-Specific MicroRNAs And Their Target In Salvia Miltiorrhiza

Salvia miltiorrhiza is one of the most popular traditional medicinal herbs in Asian nations. Its dried root contains a number of tanshinones, protocatechuic aldehyde, salvianolic acid B and rosmarinic, and is used for the treatment of various diseases. The finding of microRNAs(miRNAs) and their target genes will help understand their biological role on the biosynthesis of tanshinones in S.miltiorrhiza.In the present study, a total of 452 known miRNAs corresponding to 589 precursor miRNAs(pre-miRNAs), and 40 novel mi RNAs corresponding to 24 pre-miRNAs were identified in different tissues of S.miltiorrhiza by high-throughput sequencing, respectively. Among them, 62 miRNAs express only in root, 95 mi RNAs express only in stem, 19 miRNAs express only in leaf, and 71 miRNAs express only in flower, respectively.By the degradome analysis, 69 targets potentially cleaved by 25 miRNAs were identified. Among them, acetyl-CoA C-acetyltransferase was cleaved by miR5072, and involved in the biosynthesis of tanshinones. This study provided valuable information for understanding the tissuespecific expression patterns of miRNAs in S.miltiorrhiza and offered a foundation for future studies of the mi RNA-mediated biosynthesis of tanshinones.