Dentin sialophosphoprotein (DSPP) is highly expressed by odontoblasts, the cell type responsible for dentin formation. DSPP therefore has been extensively studied as a regulator of dentinogenesis. Besides defective dentinogenesis in teeth, Dspp-deficient mice also display reduced blood vessels in the transition zone of femurs. However, the exact role and underlying mechanisms of DSPP in the process of blood vessel formation remain enigmatic. Here, we show that dentin sialoprotein (DSP), the NH