The Role of RANKL in Bone Remodeling

Bone is a dynamic tissue resulting from coordinated phases of resorption and formation constantly,which is called bone remodeling.Receptor activator of nuclear factor κB ligand(RANKL)plays a pivotal role in the coupled balance between bone resorption and bone formation,and has the abilities to induce osteoclastogenesis,activating osteoclasts and inhibiting osteoclast apoptosis.RANKL is originally found in activated T cells,but the main sources of RANKL in bone remodeling in vivo are osteocytes,osteoblasts and marrow stromal cells.RANKL/RANK/OPG system plays a significant role in the process of osteoblasts controlling osteoclastogenesis,at the meantime,the crux of maintaining the balance of bone remodeling.This paper reviews RANKL and its molecular mechanism of action in bone.