Fig. 4.

Full-length form of DSPP from the long bone of the D452A-DSPP transgenic mice as well as from wild type mouse dentin was treated with BMP1. DSPP-related proteins were detected by Western immunoblotting using anti-DSP polyclonal antibody. The full-length form of normal DSPP was totally processed, whereas the full-length form of D452A-DSPP were partially cleaved, indicating that D452A substitution could partially block DSPP processing by BMP1. The differences in the ratio of full-length DSPP to DSP indicated that more DSPP molecules were cleaved into DSP in the wild type mice than in the transgenic mice expressing the mutant D452A-DSPP. Normal DSPP or D452A-DSPP lane: 60 μl of sample. DSP lane: 0.1 μg of rat DSP.