Fig. 5
From: Tissue-specific roles of de novo DNA methyltransferases
De novo methyltransferases play primordial role in ossification. Mesenchymal progenitor cells (MPC) differentiate to chondroblasts (CB) then chondrocytes (CC) and osteoblasts (OB) then osteocytes (OC). DNMT3B is a key regulator of this process. In the absence of Dnmt3b delayed CC maturation, osteoarthritis, impaired fracture healing is observed. Osteoclasts (OCl), responsible for bone resorption and maintaining homeostasis of ossification are differentiating from MPC (macrophages) themselves originating from myeloblasts (MB). In the absence of Dnmt3a increased bone mass was reported. Skeletal muscle development also requires DNMT3A. In knockouts decreased body weight was reported. MPSC: myogenic progenitor stem cells; MB: myoblasts; MF: myofibrillul; MT: myotube