| Function | Bone protein that constitutes 1-2% of the total bone protein, and which acts as a negative regulator of bone formation. Functions to limit bone formation without impairing bone resorption or mineralization. It binds strongly to apatite and calcium. The uncarboxylated form acts as a hormone secreted by osteoblasts, which regulates different cellular processes, such as energy metabolism, male fertility and brain development. Regulates of energy metabolism by acting as a hormone favoring pancreatic beta-cell proliferation, insulin secretion and sensitivity and energy expenditure. Uncarboxylated osteocalcin hormone also promotes testosterone production in the testes: acts as a ligand for G protein-coupled receptor GPRC6A at the surface of Leydig cells, initiating a signaling response that promotes the expression of enzymes required for testosterone synthesis in a CREB-dependent manner. Also acts as a regulator of brain development: osteocalcin hormone crosses the blood-brain barrier and acts as a ligand for GPR158 on neurons, initiating a signaling response that prevents neuronal apoptosis in the hippocampus, favors the synthesis of all monoamine neurotransmitters and inhibits that of gamma-aminobutyric acid (GABA). Osteocalcin also crosses the placenta during pregnancy and maternal osteocalcin is required for fetal brain development. |
| Protein Name | OsteocalcinBone Gla ProteinBgpGamma-Carboxyglutamic Acid-Containing Protein |
| Database Links | Reactome: R-HSA-159740Reactome: R-HSA-159763Reactome: R-HSA-159782Reactome: R-HSA-8940973 |
| Cellular Localisation | Secreted |
| Alternative Protein Names | Osteocalcin proteinBone Gla Protein proteinBgp proteinGamma-Carboxyglutamic Acid-Containing Protein proteinBGLAP protein |
Information sourced from Uniprot.org
