Regulation of IL-17 by lncRNA of IRF-2 in the pearl oyster.

Long noncoding RNAs (lncRNAs), once thought to be nonfunctional, have recently been shown to participate in the multilevel regulation of transcriptional, posttranscriptional and epigenetic modifications and to play important roles in various biological processes, including immune responses. However, the expression and roles of lncRNAs in invertebrates, especially nonmodel organisms, remain poorly understood. In this study, by comparing a transcriptome to the PfIRF-2 genomic structure, we identified lncIRF-2 in the PfIRF-2 genomic intron. The results of the RNA interference (RNAi) and the nucleus grafting experiments indicated that PfIRF-2 might have a negative regulatory effect on lncIRF-2, and PfIRF-2 and lncIRF-2 may have a positive regulatory effect on PfIL-17. Additionally, lncIRF-2, PfIRF-2 and PfIL-17 were involved in responses to the nucleus graft. These results will enhance the knowledge of lncIRF-2, IRF-2, and IL-17 functions in both pearl oysters and other invertebrates.