ELF18-INDUCED LONG NONCODING RNA 11 negatively regulates the innate immune response by suppressing Pathogenesis-related Lipase 5

Abstract

Long noncoding RNAs (lncRNAs) are essential components of diverse biological processes. However, lncRNAs involved in the innate immune response remain poorly unknown in plants. Here, we isolated ten lncRNAs named ELF18-INDUCED LONG NONCODING RNA (ELENA2 to 11) from custom lncRNA array datasets generated from Arabidopsis seedlings treated with pathogen-associated molecular patterns (PAMPs; elf18 and flg22). Each ELENA exhibited different expression patterns in a tissue- and PAMP-specific manner. ELENA11 is an intergenic lncRNA that is located between AT5G24170 and Pathogenesis-Related Lipase 5 (PRLIP5; AT5G24180). ELENA11-overexpressing plants showed reduced PRLIP5 expression and callose deposition compared to wild-type plants under elf18 and flg22 treatments, whereas ELENA11 knockout plants showed enhanced PRLIP5 expression and callose deposition, indicating that ELENA11 acts as a negative regulator of PRLIP5 expression. In addition, ELENA11-overexpressing plants were more susceptible to disease caused by Pseudomonas syringae pv. tomato DC3000 than wild-type plants, whereas ELENA11 knockout plants were resistant. These results demonstrate that ELENA11 plays a distinct role in PAMP-triggered innate immune responses by repressing PRLIP5 expression.