Identification Of Cadium-Responsive Micro RNAs In Solanum Torvum By High-throught Sequencing

MicroRNAs (miRNAs) play key roles in regulating Cd toxicity tolerance in plants. Solanum torvum is a typical low Cd-accumulating plant that has a high Cd tolerance. Despite its importance, no miRNA has been identified from S. torvum thus far. In this study, high-throughput sequencing of S. torvum small RNAs was used to identify miRNAs that were differentially expressed in response to Cd toxicity. At least 45 miRNA families and 165 individual members within those families were identified in both the control and Cd-treated S. torvum roots. Among these miRNAs,45 miRNAs from 21 miRNA families were differentially expressed in the control and Cd-treated S. torvum plants. Among these 21 differentially expressed miRNA families,6 miRNA families were upregulated in the Cd-treated roots, and 15 miRNA families were downregulated in Cd-treated roots. These results indicated that specific miRNAs are tightly regulated by Cd toxicity in the roots of S. torvum, which may play key roles in the Cd tolerance of S. torvum.