Identifcation and functional analysis of new conserved microRNAs and their targets in potato ( Solanum tuberosum L.)

Abstract

MicroRNAs (miRNAs) are tiny, endogenous, nonprotein-coding, and functionally negative regulators of posttranscriptionalgene regulation. Potato (Solanum tuberosum L.) is a starchy and tuberous crop that is also important for its potassium and vitamincontents. Tough potato is the world s fourth largest food crop, its miRNAs and their targets have not been well studied. Here we reporta comparative genomics approach that was applied to explore miRNAs and their targeted proteins in potato. A total of 120 new miRNAsfrom 110 families were identifed and characterized from the expressed sequence tags. All 120 miRNAs were observed, along with stablestem-loop precursor structures, whose lengths ranged from 42 to 488 nt with an average of 132 nt. Mature miRNAs lengths ranged from18 to 26 nt with an average of 21 nt. Later, 10 miRNAs were randomly selected for validation by reverse-transcription polymerase chainreaction. A total of 433 potential targets were predicted for these new 120 potato miRNAs. Tese targets were involved in regulation,metabolism, transcription factors, growth and development, and other physiological processes. Tese miRNAs and their targets will beuseful to fne-tune potatoes for better food content and higher nutritional value as well biotic and abiotic stress resistance.