A Long Noncoding RNA, Antisense IL-7, Promotes Inflammatory Gene Transcription through Facilitating Histone Acetylation and Switch/Sucrose Nonfermentable Chromatin Remodeling

Long noncoding RNAs are important regulators of gene expression in innate immune responses. Antisense IL-7 (IL-7-AS) is a newly discovered long noncoding RNA in human and mouse that has been reported to regulate the expression of IL-6. However, the potential function of IL-7-AS in innate immune system is not fully understood. In this study, we found that the expression of IL-7-AS is primarily dependent on the NF-κB and MAPK signaling pathways in macrophages and intestinal epithelial cells. Functionally, IL-7-AS promotes the expression of several inflammatory genes, including CCL2 , CCL5 , CCL7 , and IL-6 , in cells in response to LPS. Specifically, IL-7-AS physically interacts with p300 to regulate histone acetylation levels around the promoter regions of these gene loci. Moreover, IL-7-AS and p300 complex modulate the assembly of SWI/SNF complex to the promoters. IL-7-AS regulates chemotaxis activity of monocytes to intestine epithelial cells with involvement of CCL2. Therefore, our data indicate a new promoting role for NF-κB/MAPK-responsive IL-7-AS in the transcriptional regulation of inflammatory genes in the innate immune system although modulation of histone acetylation around the promoters of related genes.