Conclusion
Our study shows that Jmjd7, a histone demethylase, functions as a negative regulator of osteoclastogenesis, and may be a therapeutic target of bone-related diseases.
Methods
Murine macrophage-like cell line, RAW 264.7 cells, or murine bone marrow macrophages (BMMs) were treated with a receptor activator of nuclear factor B ligand (RANKL) alone or RANKL with macrophage colony-stimulating factor (M-CSF), respectively, to induce differentiation of osteoclast. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to screen different arrays of histone demethylases. Chromatin immunoprecipitation (ChIP) assay was used to examine occupancy of jumonji domain containing 7 (Jmjd7) in the promoter regions of different osteoclast-related genes. Jmjd7 was knocked down using siRNA. Dentine slice assay was used to evaluate bone-resorptive functions.
Objective
To identify and verify the histone modifier during osteoclastogenesis.
Results
Among the screened histone demethylases, Jmjd7 was significantly downregulated during differentiation of osteoclast. The occupancy of Jmjd7 at the promoter regions of osteoclast-related genes was also decreased. Knockdown of Jmjd7 in RAW 264.7 cells and BMMs enhanced differentiation of osteoclast and increased the expression of osteoclast-related genes, such as c-fos, Dc-stamp, CtsK, Acp5, and Nfatc1. Bone resorptive functions of the cells were also increased.