Calmodulin-dependent kinase II regulates osteoblast differentiation through regulation of Osterix

► CaMKII regulates the BMP4-induced osteoblastogenesis. ► CaMKII increases the protein levels and the protein stability, transcriptional activity of Osterix. ► CamKII inhibitor KN-93 inhibits Osterix-induced osteoblast differentiation and above-mentioned effects of CamKII on Osterix. ► Knockdown of CaMKII decreased the protein levels and transcriptional activity of Osterix.