Enhancer-mediated Etv4 activation stimulates osteogenic differentiation

Enhancers, as cis-regulatory elements, play pivotal roles in transcriptional homeostasis. The abnormality in enhancers is highly associated with various diseases, including osteoporosis. However, the landscape of active enhancers underlying bone diseases remains incomplete. By conducting an integrative analysis of transcriptome and ChIP-seq data, we identify enh11 as an active enhancer during osteoblastogenesis. CRISPR/Cas9-mediated deletion of enh11 inhibits cell differentiation of pre-osteoblast MC3T3-E1 cells. The osteoblast-specific knockout of enh11 reduces bone formation and decreases bone mass in mice. In addition, Etv4 is identified as the downstream target of enh11. Functional experiments both in vitro and in vivo validate that Etv4 promotes osteogenesis and bone formation. Mechanistically, enh11 upregulates the expression of Etv4 to promote osteogenesis, probably via binding to the transcription factor Stat3. These findings not only deepen our comprehension of the molecular mechanisms of enh11 underlying bone formation but also highlight enh11 and Etv4 as promising therapeutic targets for osteoporosis.