TY - JOUR
T1 - Key proteolytic cleavage site and full-length form of DSPP
AU - Sun, Y.
AU - Lu, Y.
AU - Chen, S.
AU - Prasad, M.
AU - Wang, X.
AU - Zhu, Q.
AU - Zhang, J.
AU - Ball, H.
AU - Feng, J.
AU - Butler, W. T.
AU - Qin, C.
N1 - Funding Information:
This work was supported by NIH Grant DE005092 (CQ).
PY - 2010/5
Y1 - 2010/5
N2 - It is known that dentin sialophosphoprotein (DSPP) is processed into NH2- and COOHterminal fragments, but its key cleavage site has not been identified, nor has its full-length form been discovered. The objectives of this study were to identify the key cleavage site during DSPP processing and to search for full-length DSPP in vivo. We generated a construct encoding DSPP, in which Asp452, a cleavage site residue, was replaced by Ala 452. The pulp-odontoblast complex and dentin were extracted, chromatographically separated, and assessed by Stains-All staining, Western immunoblotting, and mass spectrometry. These studies showed that the substitution of Asp452 by Ala452 completely blocks the cleavage of mouse DSPP in the transfected cells, indicating that the NH 2-terminal peptide bond of Asp452 is essential for the initiation of DSPP proteolytic processing. The results of this study revealed the presence of full-length DSPP and its processed fragments in extracts from the pulp/odontoblast and dentin.
AB - It is known that dentin sialophosphoprotein (DSPP) is processed into NH2- and COOHterminal fragments, but its key cleavage site has not been identified, nor has its full-length form been discovered. The objectives of this study were to identify the key cleavage site during DSPP processing and to search for full-length DSPP in vivo. We generated a construct encoding DSPP, in which Asp452, a cleavage site residue, was replaced by Ala 452. The pulp-odontoblast complex and dentin were extracted, chromatographically separated, and assessed by Stains-All staining, Western immunoblotting, and mass spectrometry. These studies showed that the substitution of Asp452 by Ala452 completely blocks the cleavage of mouse DSPP in the transfected cells, indicating that the NH 2-terminal peptide bond of Asp452 is essential for the initiation of DSPP proteolytic processing. The results of this study revealed the presence of full-length DSPP and its processed fragments in extracts from the pulp/odontoblast and dentin.
KW - Dentin extracellular matrix
KW - Dentin phosphoprotein
KW - Dentin sialophosphoprotein
KW - Dentin sialoprotein
KW - Proteolytic processing
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U2 - 10.1177/0022034510363109
DO - 10.1177/0022034510363109
M3 - Article
C2 - 20332332
AN - SCOPUS:77951129751
SN - 0022-0345
VL - 89
SP - 498
EP - 503
JO - Journal of dental research
JF - Journal of dental research
IS - 5
ER -