Identification of conserved miRNAs and their target genes in the damask rose (Rosa damascena Mill.)

miRNAs genes are regulatory elements that their main role is to downregulate gene expression at the mRNAs level. miRNAs also play important roles in several plant pathways related to important cellular activities such as growth, reproduction, differentiation, morphogenesis, apoptosis and, response to abiotic and biotic stresses. This research was conducted to identify conserved miRNAs and their target genes using next generation sequencing data in the damask rose (Rosa damascena Mill.). Although bioinformatics methods have been developed as the most efficient strategy for target miRNA identification, high-throughput experimental strategies are still in high demand. Bioinformatics tools (Cmii, psRNATarget, WEGO, Blast2GO) and laboratory method (real-time PCR) were used to identify new miRNAs, predict and determine the ontology of the target genes involved in the production of scent and color in the damask rose, respectively. Using EST and RNA-seq data based on Rosa lucieae homology, four miRNA families, including: miR5021, miR2673, miR156, and miR838, were selected as candidate miRNAs. In the next step, for the quantitative evaluation of the real-time PCR to validate the expression level of the selected miR5021 in two samples (white and hot-pink) and the biological stage (young and bud) of the damask rose, foliar spraying with the concentrations of zero (control) and 300 μM of methyl Jasmonate for 48 hours was made. Result showed the highest relative expression of miR5021 belonging to the pink sample on the young development stage. These findings accelerate future prospective studies on the regulatory mechanisms of miRNAs in Rosa damascena.