Alkaline phosphatase, tissue-nonspecific isozyme; This isozyme plays a key role in skeletal mineralization by regulating levels of diphosphate (PPi); Belongs to the alkaline phosphatase family.

Osteocalcin; Constitutes 1-2% of the total bone protein. It binds strongly to apatite and calcium.

Osteocalcin; Constitutes 1-2% of the total bone protein. It binds strongly to apatite and calcium.

Alkaline phosphatase, tissue-nonspecific isozyme; This isozyme plays a key role in skeletal mineralization by regulating levels of diphosphate (PPi); Belongs to the alkaline phosphatase family.

Osteocalcin; Constitutes 1-2% of the total bone protein. It binds strongly to apatite and calcium.

Dentin matrix acidic phosphoprotein 1; May have a dual function during osteoblast differentiation. In the nucleus of undifferentiated osteoblasts, unphosphorylated form acts as a transcriptional component for activation of osteoblast- specific genes like osteocalcin. During the osteoblast to osteocyte transition phase it is phosphorylated and exported into the extracellular matrix, where it regulates nucleation of hydroxyapatite.

Osteocalcin; Constitutes 1-2% of the total bone protein. It binds strongly to apatite and calcium.

Fibroblast growth factor 23 C-terminal peptide; Regulator of phosphate homeostasis. Inhibits renal tubular phosphate transport by reducing SLC34A1 levels. Upregulates EGR1 expression in the presence of KL (By similarity). Acts directly on the parathyroid to decrease PTH secretion (By similarity). Regulator of vitamin-D metabolism. Negatively regulates osteoblast differentiation and matrix mineralization.

Osteocalcin; Constitutes 1-2% of the total bone protein. It binds strongly to apatite and calcium.

Phosphate-regulating neutral endopeptidase PHEX; Peptidase that cleaves SIBLING (small integrin-binding ligand, N-linked glycoprotein)-derived ASARM peptides, thus regulating their biological activity. Cleaves ASARM peptides between Ser and Glu or Asp residues. Regulates osteogenic cell differentiation and bone mineralization through the cleavage of the MEPE-derived ASARM peptide. Promotes dentin mineralization and renal phosphate reabsorption by cleaving DMP1- and MEPE-derived ASARM peptides. Inhibits the cleavage of MEPE by CTSB/cathepsin B thus preventing MEPE degradation.

Osteocalcin; Constitutes 1-2% of the total bone protein. It binds strongly to apatite and calcium.

Parathyroid hormone; PTH elevates calcium level by dissolving the salts in bone and preventing their renal excretion. Stimulates [1-14C]-2-deoxy-D- glucose (2DG) transport and glycogen synthesis in osteoblastic cells.

25-hydroxyvitamin D-1 alpha hydroxylase, mitochondrial; A cytochrome P450 monooxygenase involved in vitamin D metabolism and in calcium and phosphorus homeostasis. Catalyzes the rate-limiting step in the activation of vitamin D in the kidney, namely the hydroxylation of 25-hydroxyvitamin D3/calcidiol at the C1alpha- position to form the hormonally active form of vitamin D3, 1alpha,25- dihydroxyvitamin D3/calcitriol that acts via the vitamin D receptor (VDR). Has 1alpha-hydroxylase activity on vitamin D intermediates of the CYP24A1-mediated inactivation pathway. Converts 24R,25-dihydrox [...]

Fibroblast growth factor 23 C-terminal peptide; Regulator of phosphate homeostasis. Inhibits renal tubular phosphate transport by reducing SLC34A1 levels. Upregulates EGR1 expression in the presence of KL (By similarity). Acts directly on the parathyroid to decrease PTH secretion (By similarity). Regulator of vitamin-D metabolism. Negatively regulates osteoblast differentiation and matrix mineralization.

25-hydroxyvitamin D-1 alpha hydroxylase, mitochondrial; A cytochrome P450 monooxygenase involved in vitamin D metabolism and in calcium and phosphorus homeostasis. Catalyzes the rate-limiting step in the activation of vitamin D in the kidney, namely the hydroxylation of 25-hydroxyvitamin D3/calcidiol at the C1alpha- position to form the hormonally active form of vitamin D3, 1alpha,25- dihydroxyvitamin D3/calcitriol that acts via the vitamin D receptor (VDR). Has 1alpha-hydroxylase activity on vitamin D intermediates of the CYP24A1-mediated inactivation pathway. Converts 24R,25-dihydrox [...]

Klotho peptide; May have weak glycosidase activity towards glucuronylated steroids. However, it lacks essential active site Glu residues at positions 239 and 872, suggesting it may be inactive as a glycosidase in vivo. May be involved in the regulation of calcium and phosphorus homeostasis by inhibiting the synthesis of active vitamin D (By similarity). Essential factor for the specific interaction between FGF23 and FGFR1 (By similarity).

25-hydroxyvitamin D-1 alpha hydroxylase, mitochondrial; A cytochrome P450 monooxygenase involved in vitamin D metabolism and in calcium and phosphorus homeostasis. Catalyzes the rate-limiting step in the activation of vitamin D in the kidney, namely the hydroxylation of 25-hydroxyvitamin D3/calcidiol at the C1alpha- position to form the hormonally active form of vitamin D3, 1alpha,25- dihydroxyvitamin D3/calcitriol that acts via the vitamin D receptor (VDR). Has 1alpha-hydroxylase activity on vitamin D intermediates of the CYP24A1-mediated inactivation pathway. Converts 24R,25-dihydrox [...]

Phosphate-regulating neutral endopeptidase PHEX; Peptidase that cleaves SIBLING (small integrin-binding ligand, N-linked glycoprotein)-derived ASARM peptides, thus regulating their biological activity. Cleaves ASARM peptides between Ser and Glu or Asp residues. Regulates osteogenic cell differentiation and bone mineralization through the cleavage of the MEPE-derived ASARM peptide. Promotes dentin mineralization and renal phosphate reabsorption by cleaving DMP1- and MEPE-derived ASARM peptides. Inhibits the cleavage of MEPE by CTSB/cathepsin B thus preventing MEPE degradation.

25-hydroxyvitamin D-1 alpha hydroxylase, mitochondrial; A cytochrome P450 monooxygenase involved in vitamin D metabolism and in calcium and phosphorus homeostasis. Catalyzes the rate-limiting step in the activation of vitamin D in the kidney, namely the hydroxylation of 25-hydroxyvitamin D3/calcidiol at the C1alpha- position to form the hormonally active form of vitamin D3, 1alpha,25- dihydroxyvitamin D3/calcitriol that acts via the vitamin D receptor (VDR). Has 1alpha-hydroxylase activity on vitamin D intermediates of the CYP24A1-mediated inactivation pathway. Converts 24R,25-dihydrox [...]

Parathyroid hormone; PTH elevates calcium level by dissolving the salts in bone and preventing their renal excretion. Stimulates [1-14C]-2-deoxy-D- glucose (2DG) transport and glycogen synthesis in osteoblastic cells.

25-hydroxyvitamin D-1 alpha hydroxylase, mitochondrial; A cytochrome P450 monooxygenase involved in vitamin D metabolism and in calcium and phosphorus homeostasis. Catalyzes the rate-limiting step in the activation of vitamin D in the kidney, namely the hydroxylation of 25-hydroxyvitamin D3/calcidiol at the C1alpha- position to form the hormonally active form of vitamin D3, 1alpha,25- dihydroxyvitamin D3/calcitriol that acts via the vitamin D receptor (VDR). Has 1alpha-hydroxylase activity on vitamin D intermediates of the CYP24A1-mediated inactivation pathway. Converts 24R,25-dihydrox [...]

Sodium-dependent phosphate transport protein 2C; May be involved in actively transporting phosphate into cells via Na(+) cotransport in the renal brush border membrane. Probably mediates 20-30% of the apical influx.

Dentin matrix acidic phosphoprotein 1; May have a dual function during osteoblast differentiation. In the nucleus of undifferentiated osteoblasts, unphosphorylated form acts as a transcriptional component for activation of osteoblast- specific genes like osteocalcin. During the osteoblast to osteocyte transition phase it is phosphorylated and exported into the extracellular matrix, where it regulates nucleation of hydroxyapatite.

Osteocalcin; Constitutes 1-2% of the total bone protein. It binds strongly to apatite and calcium.

Dentin matrix acidic phosphoprotein 1; May have a dual function during osteoblast differentiation. In the nucleus of undifferentiated osteoblasts, unphosphorylated form acts as a transcriptional component for activation of osteoblast- specific genes like osteocalcin. During the osteoblast to osteocyte transition phase it is phosphorylated and exported into the extracellular matrix, where it regulates nucleation of hydroxyapatite.

Fibroblast growth factor 23 C-terminal peptide; Regulator of phosphate homeostasis. Inhibits renal tubular phosphate transport by reducing SLC34A1 levels. Upregulates EGR1 expression in the presence of KL (By similarity). Acts directly on the parathyroid to decrease PTH secretion (By similarity). Regulator of vitamin-D metabolism. Negatively regulates osteoblast differentiation and matrix mineralization.

Dentin matrix acidic phosphoprotein 1; May have a dual function during osteoblast differentiation. In the nucleus of undifferentiated osteoblasts, unphosphorylated form acts as a transcriptional component for activation of osteoblast- specific genes like osteocalcin. During the osteoblast to osteocyte transition phase it is phosphorylated and exported into the extracellular matrix, where it regulates nucleation of hydroxyapatite.

Matrix extracellular phosphoglycoprotein; Promotes renal phosphate excretion and inhibits intestinal phosphate absorption. Promotes bone mineralization by osteoblasts and cartilage mineralization by chondrocytes. Regulates the mineralization of the extracellular matrix of the craniofacial complex, such as teeth, bone and cartilage (By similarity). Promotes dental pulp stem cell proliferation and differentiation. Belongs to the PF07175/osteoregulin family.

Dentin matrix acidic phosphoprotein 1; May have a dual function during osteoblast differentiation. In the nucleus of undifferentiated osteoblasts, unphosphorylated form acts as a transcriptional component for activation of osteoblast- specific genes like osteocalcin. During the osteoblast to osteocyte transition phase it is phosphorylated and exported into the extracellular matrix, where it regulates nucleation of hydroxyapatite.

Phosphate-regulating neutral endopeptidase PHEX; Peptidase that cleaves SIBLING (small integrin-binding ligand, N-linked glycoprotein)-derived ASARM peptides, thus regulating their biological activity. Cleaves ASARM peptides between Ser and Glu or Asp residues. Regulates osteogenic cell differentiation and bone mineralization through the cleavage of the MEPE-derived ASARM peptide. Promotes dentin mineralization and renal phosphate reabsorption by cleaving DMP1- and MEPE-derived ASARM peptides. Inhibits the cleavage of MEPE by CTSB/cathepsin B thus preventing MEPE degradation.

Dentin matrix acidic phosphoprotein 1; May have a dual function during osteoblast differentiation. In the nucleus of undifferentiated osteoblasts, unphosphorylated form acts as a transcriptional component for activation of osteoblast- specific genes like osteocalcin. During the osteoblast to osteocyte transition phase it is phosphorylated and exported into the extracellular matrix, where it regulates nucleation of hydroxyapatite.

Parathyroid hormone; PTH elevates calcium level by dissolving the salts in bone and preventing their renal excretion. Stimulates [1-14C]-2-deoxy-D- glucose (2DG) transport and glycogen synthesis in osteoblastic cells.

Fibroblast growth factor 23 C-terminal peptide; Regulator of phosphate homeostasis. Inhibits renal tubular phosphate transport by reducing SLC34A1 levels. Upregulates EGR1 expression in the presence of KL (By similarity). Acts directly on the parathyroid to decrease PTH secretion (By similarity). Regulator of vitamin-D metabolism. Negatively regulates osteoblast differentiation and matrix mineralization.

Osteocalcin; Constitutes 1-2% of the total bone protein. It binds strongly to apatite and calcium.

Fibroblast growth factor 23 C-terminal peptide; Regulator of phosphate homeostasis. Inhibits renal tubular phosphate transport by reducing SLC34A1 levels. Upregulates EGR1 expression in the presence of KL (By similarity). Acts directly on the parathyroid to decrease PTH secretion (By similarity). Regulator of vitamin-D metabolism. Negatively regulates osteoblast differentiation and matrix mineralization.

25-hydroxyvitamin D-1 alpha hydroxylase, mitochondrial; A cytochrome P450 monooxygenase involved in vitamin D metabolism and in calcium and phosphorus homeostasis. Catalyzes the rate-limiting step in the activation of vitamin D in the kidney, namely the hydroxylation of 25-hydroxyvitamin D3/calcidiol at the C1alpha- position to form the hormonally active form of vitamin D3, 1alpha,25- dihydroxyvitamin D3/calcitriol that acts via the vitamin D receptor (VDR). Has 1alpha-hydroxylase activity on vitamin D intermediates of the CYP24A1-mediated inactivation pathway. Converts 24R,25-dihydrox [...]

Fibroblast growth factor 23 C-terminal peptide; Regulator of phosphate homeostasis. Inhibits renal tubular phosphate transport by reducing SLC34A1 levels. Upregulates EGR1 expression in the presence of KL (By similarity). Acts directly on the parathyroid to decrease PTH secretion (By similarity). Regulator of vitamin-D metabolism. Negatively regulates osteoblast differentiation and matrix mineralization.

Dentin matrix acidic phosphoprotein 1; May have a dual function during osteoblast differentiation. In the nucleus of undifferentiated osteoblasts, unphosphorylated form acts as a transcriptional component for activation of osteoblast- specific genes like osteocalcin. During the osteoblast to osteocyte transition phase it is phosphorylated and exported into the extracellular matrix, where it regulates nucleation of hydroxyapatite.

Fibroblast growth factor 23 C-terminal peptide; Regulator of phosphate homeostasis. Inhibits renal tubular phosphate transport by reducing SLC34A1 levels. Upregulates EGR1 expression in the presence of KL (By similarity). Acts directly on the parathyroid to decrease PTH secretion (By similarity). Regulator of vitamin-D metabolism. Negatively regulates osteoblast differentiation and matrix mineralization.

Klotho peptide; May have weak glycosidase activity towards glucuronylated steroids. However, it lacks essential active site Glu residues at positions 239 and 872, suggesting it may be inactive as a glycosidase in vivo. May be involved in the regulation of calcium and phosphorus homeostasis by inhibiting the synthesis of active vitamin D (By similarity). Essential factor for the specific interaction between FGF23 and FGFR1 (By similarity).