Abstract
Macrophages are mainly divided into two populations, which play a different role in physiological and pathological conditions. The differentiation of these cells may be regulated by transcription factors. However, it is unclear how to modulate these transcription factors to affect differentiation of these cells. Here, we found that lncLy6C, a novel ultraconserved lncRNA, promotes differentiation of Ly6Chigh inflammatory monocytes into Ly6Clow/neg resident macrophages. We demonstrate that gut microbiota metabolites butyrate upregulates the expression of lncLy6C. LncLy6C deficient mice had markedly increased Ly6Chigh pro-inflammatory monocytes and reduced Ly6Cneg resident macrophages. LncLy6C not only bound with transcription factor C/EBPβ but also bound with multiple lysine methyltransferases of H3K4me3 to specifically promote the enrichment of C/EBPβ and H3K4me3 marks on the promoter region of Nr4A1, which can promote Ly6Chigh into Ly6Cneg macrophages. As a result, lncLy6C causes the upregulation of Nr4A1 to promote Ly6Chigh inflammatory monocytes to differentiate into Ly6Cint/neg resident macrophages.