Barley Long Non-Coding RNAs and Their Tissue-Specific Co-expression Pattern with Coding-Transcripts

Long non-coding RNAs (lncRNA) with non-protein or small peptide-coding potential transcripts are emerging regulatory molecules. With the advent of next-generation sequencing technologies and novel bioinformatics tools, a tremendous number of lncRNAs has been identified in several plant species. Recent reports demonstrated roles of plant lncRNAs such as development and environmental response. Here, we reported a genome-wide discovery of ~8,000 barley lncRNAs and measured their expression pattern upon excessive boron (B) treatment. According to the tissue-based comparison, leaves have a greater number of B-responsive differentially expressed lncRNAs than the root. Functional annotation of the coding transcripts, which were co-expressed with lncRNAs, revealed that molecular function of the ion transport, establishment of localization, and response to stimulus significantly enriched only in the leaf. On the other hand, 32 barley endogenous target mimics (eTM) as lncRNAs, which potentially decoy the transcriptional suppression activity of 18 miRNAs, were obtained. Presented data including identification, expression measurement, and functional characterization of barley lncRNAs suggest that B-stress response might also be regulated by lncRNA expression via cooperative interaction of miRNA-eTM-coding target transcript modules.