Genome-wide identification and characterization of drought responsive MicroRNAs in Solanum tuberosum L.

MicroRNAs (miRNAs) are small non-coding RNAs that function as negative post-transcriptional regulators during plant growth and development in response to biotic and abiotic stresses. The objective of this study was to use next-generation sequencing (miRNA-sequencing) technology to identify drought responsive miRNAs from potato (Solanum tuberosum L.). After inducing small RNA under experimental conditions of aeration without watering for 1, 3, and 6 h compared to those at 0 h control, NGS was used to identify drought responsive miRNAs. From these drought responsive miRNAs, 21 known miRNAs and 19 novel miRNAs were selected. Of them, 38 were subjected to expression level analysis under four abiotic stresses (drought, salt, cold and abscisic acid) treatment through northern blot while two novel miRNAs were subjected to quantitative reverse transcription PCR (qRT-PCR) to determine their expression levels. The effects of other abiotic stresses such as cold, salt, and ABA treatments on the expression levels of the 38 drought responsive miRNAs were also analyzed. Putative target gene regulatory network of novel miRNAs were determined through computational analysis.