Synonyms:Dentin matrix protein 4, DMP 4, DMP4, FAM20C, Protein FAM20C, RNS Background:Golgi serine/threonine protein kinase that phosphorylates secretory pathway proteins within Ser-x-Glu/pSer motifs and plays a key role in biomineralization of bones and teeth(PubMed:22582013, PubMed:23754375, PubMed:25789606). Constitutes the main protein kinase for extracellular proteins, generating the majority of the extracellular phosphoproteome(PubMed:26091039). Mainly phosphorylates proteins within the Ser-x-Glu/pSer motif, but also displays a broader substrate specificity(PubMed:26091039). Phosphorylates casein as well as a number of proteins involved in biomineralization such as AMELX, AMTN, ENAM and SPP1(PubMed:22582013, PubMed:25789606). In addition to its role in biomineralization, also plays a role in lipid homeostasis, wound healing and cell migration and adhesion(PubMed:26091039).