Synthesis, Storage, and Release
| Oxytocin, prepropeptide | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Identifiers | |||||||||||||
| Symbols | OXT; OT; OT-NPI | ||||||||||||
| External IDs | OMIM: 167050 MGI: 97453 HomoloGene: 55494 GeneCards: OXT Gene | ||||||||||||
|
|||||||||||||
| Orthologs | |||||||||||||
| Species | Human | Mouse | |||||||||||
| Entrez | 5020 | 18429 | |||||||||||
| Ensembl | ENSG00000101405 | ENSMUSG00000027301 | |||||||||||
| UniProt | P01178 | P35454 | |||||||||||
| RefSeq (mRNA) | NM_000915.2 | NM_011025.3 | |||||||||||
| RefSeq (protein) | NP_000906.1 | NP_035155.1 | |||||||||||
| Location (UCSC) | Chr 20: 3.05 – 3.05 Mb |
Chr 2: 130.58 – 130.58 Mb |
|||||||||||
| PubMed search | |||||||||||||
The oxytocin peptide is synthesized as an inactive precursor protein from the OXT gene. This precursor protein also includes the oxytocin carrier protein neurophysin I. The inactive precursor protein is progressively hydrolyzed into smaller fragments (one of which is neurophysin I) via a series of enzymes. The last hydrolysis that releases the active oxytocin nonapeptide is catalyzed by peptidylglycine alpha-amidating monooxygenase (PAM).
The activity of the PAM enzyme system is dependent upon vitamin C (ascorbate), which is a necessary vitamin cofactor. By chance, sodium ascorbate by itself was found to stimulate the production of oxytocin from ovarian tissue over a range of concentrations in a dose-dependent manner. Many of the same tissues (e.g. ovaries, testes, eyes, adrenals, placenta, thymus, pancreas) where PAM (and oxytocin by default) is found are also known to store higher concentrations of vitamin C.
Read more about this topic: Oxytocin
Famous quotes containing the word release:
“The shallow consider liberty a release from all law, from every constraint. The wise man sees in it, on the contrary, the potent Law of Laws.”
—Walt Whitman (1819–1892)