Genome-wide analysis of lncRNA in wheat (Triticum aestivum) and functional characterization of TalncR9 in response to drought stress

Long noncoding RNAs (lncRNAs) play essential roles in a variety of biological processes in plants. While many lncRNAs have been identified, their functional roles in wheat (<i>Triticum aestivum</i>) remain largely unknown. In this study, we identified 2830 lncRNAs in wheat using RNA-sequencing data derived from drought treatment, among which 323 were found to be significantly responsive to drought stress. GO and KEGG analyses indicated that the target genes were significantly enriched in categories related to binding and catalytic activities, response to various stimuli, plant hormone signal transduction, and other stress resistance pathways. Additionally, we identified 56 TalncRNAs that could potentially serve as target mimics for 38 different miRNAs. A ceRNA network was constructed, which included 19 lncRNA-miRNA-mRNA interactions, comprising 9 lncRNAs, 6 miRNAs, and 14 mRNAs. Silencing <i>TalncR9</i> in wheat reduced drought tolerance, decreased soluble sugar and proline levels, and increasing MDA levels. <i>TalncR9</i> overexpression in <i>Arabidopsis</i> enhanced drought resistance, increasing germination rates and root length under mannitol treatment. <i>TalncR9</i> up-regulated drought-related genes (<i>LEA30</i>, <i>DREB2</i>, etc.) in transgenic line. These results demonstrate <i>TalncR9</i>'s role as a positive drought regulator and provide insights for improving wheat resilience.