First Author | George A | Year | 1996 |
Journal | J Biol Chem | Volume | 271 |
Issue | 51 | Pages | 32869-73 |
PubMed ID | 8955126 | Mgi Jnum | J:37297 |
Mgi Id | MGI:84699 | Doi | 10.1074/jbc.271.51.32869 |
Citation | George A, et al. (1996) The carboxyl-terminal domain of phosphophoryn contains unique extended triplet amino acid repeat sequences forming ordered carboxyl-phosphate interaction ridges that may be essential in the biomineralization process. J Biol Chem 271(51):32869-73 |
abstractText | Phosphophoryns (PPs), a family of Asp and Ser(P)-rich dentin proteins, are considered to be archetypal regulators of several aspects of extracellular matrix (ECM) biomineralization. We have cloned a rat incisor PP gene, Dmp2, from our odontoblast cDNA library and localized it to mouse chromosome 5q21 within 2 centimorgans of Dmp1, another tooth-specific ECM protein. The carboxyl-terminal region of Dmp2 protein (60 residue % Ser, 31 residue % Asp) is divided into two domains, one with unique repetitive blocks of [DSS]n,3</=14, the other with [SD]m = 2,3. Conformational analysis shows the phosphorylated form of the [DS*S*]n repeats to have a unique structure with well defined ridges of phosphates and carboxyls available for counter ion binding. The [S*D]m domains have different phosphate and carboxylate interaction edges and thus different calcium ion and apatite surface binding properties. These two domains and the colocalization of Dmp1 and Dmp2 genes at a position equivalent to the dentinogenesis imperfecta type II location on human 4q21 all suggest that the PPs are indeed involved in some aspect of ECM mineralization. |