Indexed on: 01 Dec '17Published on: 08 May '17Published in: Plant Molecular Biology Reporter
MicroRNAs (miRNAs) are small, single-stranded, non-coding endogenous RNAs that play vital roles in the regulation of gene expression at the post-transcriptional level. Several studies of miRNAs in diploid and tetraploid Paulownia plants have been reported; however, miRNAs involved in response to drought stress have not yet been investigated. In this study, six small RNA libraries of Paulownia fortunei, two drought-treated and four controls, were built and then sequenced on an Illumina/Solexa GAIIx platform. A total of 30 conserved miRNAs and 88 novel miRNAs were identified in the sRNA libraries. Among them, 22 miRNAs in common were differentially expressed both in diploid and tetraploid P. fortunei under the drought stress. Degradome sequencing was used to identify the target genes of the miRNAs. Moreover, nine differentially expressed miRNAs and ten target genes were validated by quantitative real-time polymerase chain reaction (qRT-PCR). This study has provided data for further research into the molecular mechanisms associated with drought stress in diploid and autotetraploid P. fortunei plants.