Parathyroid hormone

PTH
Available structures
PDB	Ortholog search: PDBe RCSB
List of PDB id codes
	1BWX, 1ET1, 1FVY, 1HPH, 1HPY, 1HTH, 1ZWA, 1ZWB, 1ZWD, 1ZWE, 1ZWF, 1ZWG, 2L1X, 3C4M
Identifiers
Aliases	PTH, PTH1, parathyroid hormone, Parathyroid hormone, FIH1
External IDs	OMIM: 168450; MGI: 97799; HomoloGene: 266; GeneCards: PTH; OMA:PTH - orthologs
Gene location (Human)
Chr.	Chromosome 11 (human)
End	13,496,181 bp
Gene location (Mouse)
Chr.	Chromosome 7 (mouse)
End	112,987,777 bp
RNA expression pattern
	Top expressed in
	testicle; ; retinal pigment epithelium; ; muscle tissue; ; body of stomach; ; fundus; ; embryo; ; fallopian tube; ; smooth muscle tissue; ; ganglionic eminence; ; mammary gland;
	Top expressed in
	trachea; ; parathyroid; ; esophagus; ; superior colliculus; ; medulla oblongata; ; pancreas; ; submandibular gland; ; morula; ; thymus; ; gastrula;
	More reference expression data
	More reference expression data
Gene ontology
Molecular function	transcription factor activity, RNA polymerase II distal enhancer sequence-specific binding; hormone activity; parathyroid hormone receptor binding; type 1 parathyroid hormone receptor binding; protein N-terminus binding; receptor ligand activity; peptide hormone receptor binding; DNA-binding transcription factor activity, RNA polymerase II-specific; protein binding;
Cellular component	intracellular anatomical structure; extracellular region; extracellular space;
Biological process	positive regulation of signal transduction; positive regulation of cell proliferation in bone marrow; positive regulation of osteoclast proliferation; response to fibroblast growth factor; hormone-mediated apoptotic signaling pathway; cAMP metabolic process; response to ethanol; response to parathyroid hormone; skeletal system development; positive regulation of ossification; response to lead ion; response to nutrient levels; G protein-coupled receptor signaling pathway; response to vitamin D; negative regulation of apoptotic process in bone marrow cell; negative regulation of transcription by RNA polymerase II; cellular macromolecule biosynthetic process; cellular calcium ion homeostasis; homeostasis of number of cells within a tissue; response to cadmium ion; Rho protein signal transduction; positive regulation of glucose import; positive regulation of glycogen biosynthetic process; bone resorption; positive regulation of bone mineralization; regulation of gene expression; positive regulation of transcription by RNA polymerase II; cell-cell signaling; activation of phospholipase C activity; negative regulation of chondrocyte differentiation; positive regulation of inositol phosphate biosynthetic process; negative regulation of bone mineralization involved in bone maturation; regulation of signaling receptor activity; adenylate cyclase-activating G protein-coupled receptor signaling pathway; calcium ion transport; magnesium ion homeostasis; bone mineralization; phosphate ion homeostasis; calcium ion homeostasis; negative regulation of calcium ion transport;
	Sources:Amigo / QuickGO
Orthologs
	5741
	19226
	ENSG00000152266
	ENSMUSG00000059077
	P01270
	Q9Z0L6
	NM_000315; NM_001316352
	NM_020623
	NP_000306; NP_001303281
	NP_065648
	Wikidata
View/Edit Human	View/Edit Mouse

Parathyroid hormone (PTH), also known as parathormone or parathyrin, is a peptide hormone secreted by the parathyroid glands. It plays a critical role in regulating serum calcium and phosphate levels through its actions on bone, kidneys, and the small intestine. PTH increases serum calcium levels and is opposed by calcitonin. It also promotes the synthesis of calcitriol, the active form of vitamin D.

PTH is secreted in response to low blood serum calcium (Ca²⁺) levels and is a key regulator of bone remodeling, the continuous process of bone resorption and formation. PTH indirectly stimulates osteoclast activity, promoting the release of calcium from the bone matrix to restore serum calcium levels. The bones serve as a reservoir of calcium, releasing it as needed to maintain homeostasis in the face of fluctuating metabolism, stress, and nutritional status.

Produced primarily by the chief cells of the parathyroid glands, PTH is a polypeptide prohormone (precursor to a hormone) consisting of 84 amino acids and has a molecular mass of approximately 9500 Da. Its gene is located on chromosome 11 in humans.

PTH exerts its biological effects via two main receptors. The Parathyroid hormone 1 receptor, activated by the 34 N-terminal amino acids of PTH, is highly expressed in bone and kidney cells. The Parathyroid hormone 2 receptor is predominantly found in the central nervous system, pancreas, testes, and placenta. The hormone has a short half-life of approximately 4 minutes. Dysregulation of PTH secretion, as seen in conditions like hypoparathyroidism, hyperparathyroidism, and paraneoplastic syndromes, can result in bone disease, hypocalcemia, or hypercalcemia.