Regulation of BMP-induced osteoblastic differentiation by Ubc9 knockdown-mediated inhibition of SUMO modification

BackgroundBone morphogenetic proteins (BMPs) belong to the transforming growth factor-β (TGF-β) superfamily. BMPs can induce ectopic bone formation, and they play an important role in osteoblast differentiation. SUMOylation, which is a ubiquitin-like post-translational modification, has been reported to regulate various biological events such as the response to DNA damage, tumorigenesis, mitotic chromosome segregation, and transcription. Although Smad4, which acts as a transcriptional factor in BMP signaling, is a target of SUMOylation, the effect of its SUMOylation on osteoblast differentiation remains unclear.ConclusionThese findings suggest that Ubc9 inhibits osteoblastic differentiation induced by BMP, at least in part, via SUMOylation of Smad4 and that the SUMOylation pathway is involved in osteoblastic differentiation in vivo.