Long noncoding RNAs (lncRNAs) affect gene expression through a wide range of mechanisms and are considered as important regulators in many essential biological processes. A large number of lncRNA transcripts have been predicted or identified in plants in recent years. However, the biological functions for most of them are still unknown. In this study, we identified an Arabidopsis (Arabidopsis thaliana) lncRNA, DROUGHT INDUCED lncRNA (DRIR), as a novel positive regulator of the plant response to drought and salt stress. DRIR was expressed at a low level under nonstress conditions but can be significantly activated by drought and salt stress as well as by abscisic acid (ABA) treatment. We identified a T-DNA insertion mutant, drir D , which had higher expression of the DRIR gene than the wild-type plants. The drir D mutant exhibits increased tolerance to drought and salt stress. Overexpressing DRIR in Arabidopsis also increased tolerance to drought and salt stress of the transgenic plants. The drir D mutant and the overexpressing seedlings are more sensitive to ABA than the wild type in stomata closure and seedling growth. Genome-wide transcriptome analysis demonstrated that the expression of a large number of genes was altered in drir D and the overexpressing plants. These include genes involved in ABA signaling, water transport, and other stress-relief processes. Our study reveals a mechanism whereby DRIR regulates the plant response to abiotic stress by modulating the expression of a series of genes involved in the stress response.

Data availabilitySummary statistics generated by COVID-19 Host Genetics Initiative are available online (https://www.covid19hg.org/results/r6/). The analyses described here use the freeze 6 data. The COVID-19 Host Genetics Initiative continues to regularly release new data freezes. Summary statistics for samples from individuals of non-European ancestry are not currently available owing to the small individual sample sizes of these groups, but the results for 23 loci lead variants are reported in Supplementary Table 3. Individual-level data can be requested directly from the authors of the contributing studies, listed in Supplementary Table 1.

In 1874, the German scientist Johann Ludwig Wilhelm Thudichum identified sphingolipids, as a class of lipids highly enriched in the central nervous system (CNS). Sphingolipids are the second most abundant membrane lipids after phospholipids (Merrill et al., 1997). This class of lipids shows great diversity and complexity, and has been implicated in CNS development and function. Indeed, sphingolipids are not only structural components of the cell membrane, they play important roles in cellular processes such as endocytosis, intracellular trafficking, and signal transduction (Hannun & Obeid, 2008).