Long non-coding RNAs in the alkaline stress response in sugar beet (Beta vulgaris L.)

BACKGROUND: Long noncoding RNAs (lncRNAs) play crucial roles in regulating numerous biological processes in which complicated mechanisms are involved. Nonetheless, little is known about the number, features, sequences, and possible effects of lncRNAs on plant responses to alkaline stress. RESULTS: Leaf samples collected based on the control Beta vulgaris L., as well as those under short-term and long-term alkaline treatments, were subjected to high-throughput RNA sequencing, through which a total of 8535 lncRNAs with reliable expression were detected. Of these lncRNAs, 102 and 49 lncRNA expression profiles were altered after short- and long-term alkaline stress, respectively. Moreover, 7 lncRNAs were recognized as precursors to 17 previously identified miRNAs. Four lncRNAs responsive to alkaline stress were estimated as targets for 8 miRNAs. Moreover, computational analysis predicted 4318 potential target genes as lncRNAs responsive to alkaline stress. Analysis of functional annotations showed that the abovementioned possible target genes were involved in various bioprocesses, such as kinase activity, structural constituents of ribosomes, the ribonucleoprotein complex and protein metabolic processes. Association analysis provided convincing proof of the interplay of specific candidate target genes with lncRNAs. CONCLUSION: LncRNAs likely exert vital roles during the regulation of the alkaline stress response and adaptation in plants through interaction with protein-coding genes. The findings of this study contribute to comprehensively examining lncRNAs in Beta vulgaris L. and shed more light on the possible roles and modulating interplays of lncRNAs responsive to alkaline stress, thereby laying a certain basis for functional analyses of these types of Beta vulgaris L. lncRNAs in the future.