ISSN: 2329-8936
Vibha Mandhan and Kashmir Singh
Stevia rebaudiana Bertoni, due to its nutritional importance and its emerging use as natural sweetener, is gaining attention worldwide. To better understand the gene regulatory network of this plant, we have initiated high-throughput small RNAs sequencing to discover novel microRNAs (miRNAs). miRNAs are a class of short endogenous non-coding small RNA molecules of about 18-22 nucleotides in length whose main function is to down regulate gene expression in different manners like translational repression, mRNA cleavage and epigenetic modification. We constructed S. rebaudiana sRNA library and after sequencing it using illumina genome analyzer II, a total of 30,472,534 reads representing 2,509,190 distinct sequences were obtained. From these reads, twelve 12 novel miRNAs were predicted whose precursors were potentially generated from stevia EST and nucleotide sequences. All novel sequences have not been described earlier in stevia or other plant species. Putative target genes were predicted for most novel miRNAs which include mainly mRNA encoding enzymes regulating essential plant metabolic and signaling pathways. Our result has increased the number of miRNAs in stevia, which should be useful for further investigation into the biological functions and evolution of miRNAs in stevia and other plant species.