Abstract
Osteoclasts are required for bone resorption. A new study in mice indicates that osteoclast differentiation is stabilized by DNA methylation at Irf8 (encoding interferon regulatory factor 8) mediated by DNA methyltransferase 3a (Dnmt3a), which suppresses Irf8 gene expression. The activity of Dnmt3 in osteoclasts requires elevated oxidative metabolism.