Computational Prediction of Conserved microRNAs from Solanum tuberosum

MicroRNAs represent a class of non-coding endogenous small RNAs ~22 nt in length that play important regulatory roles in plant growth and development. Although an explosive increase in number of plant miRNAs have been documented in recent years, by cloning or computational approaches, only limited miRNAs have been reported in potato, which is an important crop worldwide. By searching the known miRNAs from 20 plant species against EST (Expressed Sequence Tags) sequences with bioinformatics methods, 71 miRNAs belonging to 48 families were predicted from this crop. Amongst, 65 were forecasted for the first time. Most potato miRNA families have one to three members, while miR474 has four. Sequence analysis showed that the candidate pre-miRNA sequences varied from 48-224 bp in length.