Identification, expression analysis, and potential roles of microRNAs in the regulation of polysaccharide biosynthesis in Polygonatum cyrtonema Hua

MicroRNAs (miRNAs) are a group of endogenous small non-coding RNAs with important roles in plant growth, development, and metabolic processes. Polygonatum cyrtonema Hua (P. cyrtonema) is an Chinese traditional medicinal herb broad pharmacological functions, polysaccharides the main biological substance accumulated P. rhizome. However, regulation process polysaccharide biosynthesis remains largely unknown.To elucidate miRNAs their targets involved cyrtonema, four RNA libraries were constructed from flower, leaf, rhizome, root tissues sequenced. A total 69 conserved 5 novel identified, which 6 (miR156a-5p, miR156f-5p, miR395a-5, miR396a-3p, miR396g-3p, miR397-5p-1) down-regulated 7 (miR160, miR160h-1, miR160e-5p, miR319b-1, miR319-1, miR319c-5p-3, miR319c-1) up-regulated rhizomes compared tissues. Bioinformatics analysis showed that predicted these mostly transcription factors functional genes enriched secondary metabolite biosynthetic pathways, paired identified carbohydrate metabolism. qRT-PCR expression demonstrated metabolism existed negative correlation in. MiR396a-3p one its target genes, abfA, possibly pathway. This first report on identification potential thus providing molecular evidence for role cyrtonema.