Regulates renal phosphate and uric acid excretion (PubMed:26051469). Regulates bone mineralization by osteoblasts and cartilage mineralization by chondrocytes (PubMed:11414762, PubMed:12421822, PubMed:15843468, PubMed:22766095). Regulates the mineralization of the extracellular matrix of the craniofacial complex, such as teeth, bone and cartilage (PubMed:26927967). Increases dental pulp stem cell proliferation (By similarity). Interacts (via ASARM motif) with PHEX; the interaction is zinc-dependent. Expressed in osteocytes (at protein level) (PubMed:12421822, PubMed:15221418). Expressed by chondrocytes, specifically in the hypertrophic zone of the bone growth plate (at protein level) (PubMed:22766095). Expressed in osteoblasts in bone (at protein level) (PubMed:11414762, PubMed:15221418, PubMed:18597632). Expressed by osteoblasts within the metaphysis (at protein level) (PubMed:15221418, PubMed:22766095). Expressed at low levels in white fat, brown fat, testes, brain and aorta (PubMed:12421822). Expressed in the craniofacial complex (at protein level) (PubMed:26927967). Expressed in odontoblasts, ameloblasts and in predentin during tooth development (at protein level) (PubMed:22042093). Expressed in the kidney (at protein level) (PubMed:26051469). Expressed in osteocytes in mandibular condylar cartilage and tibial cartilage (at protein level) (PubMed:26428891). Expressed in salivary glands (PubMed:15329369). Detected at 16 days post coitum (dpc) in both epithelial and mesenchymal components of the tooth organ (PubMed:26927967). Also detected at 16 dpc and 18 dpc in mandibular bone osteocytes (PubMed:26428891). Detected at 15 dpc in the bone collar (PubMed:26428891). Detected at 13 dpc in the cartilage matrix (PubMed:26428891). Detected at postnatal day 3 in odontoblasts and ameloblasts (PubMed:22042093). At postnatal day 5, expression is decreased in dental papilla cells, but increased in the predentin (PubMed:22042093). By postnatal day 9, is only detected in the predentin (PubMed:22042093). Detected at postnatal day 2 in osteoblasts, the calcified cartilage cores in primary metaphyseal bone and in osterocytes embedded in cortical bone matrix (PubMed:15221418). At postnatal day 84 expression is detected in the osteocytes of cortical and trabecular bone (PubMed:15221418). Induced by ascorbate and beta-glycerophosphate (PubMed:11414762, PubMed:12421822). Induced expression during bone fracture healing, with low levels of expression being detected in fibroblast-like cells at 6 days post-fracture, and increased expression at 10 days post-fracture in late hypertrophic chondrocytes. At 14 days post-fracture, expression is detected in osteocytes, osteoblasts, and hypertrophic chondrocytes. By 28 days post-fracture, expression was highest in osteocytes and lower in osteoblasts (PubMed:15221418). Down-regulated by 1-alpha-25-dihydroxyvitamin D3 (calcitriol) (PubMed:11414762). The acidic serine aspartate-rich MEPE-associated (ASARM) motif is sufficient when phosphorylated to inhibit bone mineralization by osteoblasts and cartilage mineralization by chondrocytes by binding hydroxyapatite crystals during the mineralization stage (PubMed:15843468, PubMed:22766095, PubMed:26051469). It can also inhibit dentin mineralization (By similarity). The dentonin region is sufficient to promote dental pulp stem cell proliferation. It can also stimulate bone formation, osteoblast differentiation, and activate integrin signaling pathways. Phosphorylated on serine residues in the ASARM motif; the phosphorylation is important for the inhibition of bone mineralization. Cleaved by CTSB/cathepsin B; the cleavage is blocked by metalloprotease PHEX. Mutant mice exhibit increased cancellous bone mass and no loss of trabecular bone characteristics (PubMed:12421822, PubMed:26051469). They also exhibit decreased biomechanical strength in their bones and increased skeletal mineralization (PubMed:15843468). In craniofacial complex development, mutant mice also exhibit hypermineralization in predentin, dentin and enamel of teeth and decreased expression of AMBN, ENAM, IBSP, DMP1, DSPP and SPP1 (PubMed:26927967). Mutant mice also exhibit hyperphostatemia and increased expression of SLC34A1/NPT2a, SLC34A3/NPT2c and VEGF in the kidney (PubMed:26051469). Hyperuricemia and reduced fractional excretion of uric acid was also exhibited (PubMed:26051469). As mutant mice age, bone mineral density and content is increased (PubMed:26051469). It has been proposed that MEPE is cleaved and generate 2 peptides dentonin and ASARM peptide. Belongs to the PF07175/osteoregulin family. Truncated N-terminus. Truncated N-terminus.