Thyroid peroxidase
You don't need to be Editor-In-Chief to add or edit content to WikiDoc. You can begin to add to or edit text on this WikiDoc page by clicking on the edit button at the top of this page. Next enter or edit the information that you would like to appear here. Once you are done editing, scroll down and click the Save page button at the bottom of the page.
| thyroid peroxidase
| |
| Identifiers | |
| Symbol | TPO |
| Entrez | 7173 |
| HUGO | 12015 |
| OMIM | 606765 |
| RefSeq | NM_175722 |
| UniProt | P07202 |
| Other data | |
| EC number | 1.11.1.8 |
| Locus | Chr. 2 pter-p24 |
Thyroid peroxidase or Thyroperoxidase (TPO) is an enzyme mainly expressed in the thyroid that liberates iodine for addition onto tyrosine residues on thyroglobulin for the production of thyroxine (T4) or triiodothyronine (T3) (thyroid hormones).
Inorganic iodine enters the body primarily as iodide, I-. After entering the thyroid follicle(or thyroid follicular cell) via a Na+/I- symporter (NIS) on the basolateral side, iodide is shuttled across the apical membrane into the colloid via pendrin, after which thyroid peroxidase oxidizes iodide to atomic iodine (I) or iodinium (I+). The "organification of iodine," the incorporation of iodine to thyroglobulin for the production of thyroid hormone is inseparable from oxidation and is catalyzed by TPO. The chemical reactions catalyzed by thyroid peroxidase occur on the outer apical membrane surface and are mediated by hydrogen peroxide.
Stimulation and inhibition
TPO is stimulated by TSH, which upregulates gene expression. It is inhibited by the thioamide drugs, such as propylthiouracil and methimazole.
Clinical significance
It is a frequent epitope of autoantibodies in autoimmune thyroid disease so the antibody titer can be used to assess disease activity in patients who have developed such antibodies.
External links
 | This medical article is a stub. You can help WikiDoc by expanding it. |
Oxidoreductases: peroxidases (EC 1.11) |
|---|
| Catalase - Cytochrome c peroxidase - Eosinophil peroxidase - Glutathione peroxidase - Horseradish peroxidase - Lactoperoxidase - Myeloperoxidase - Thyroid peroxidase - Deiodinase (Tetraiodothyronine 5' deiodinase) |
Acknowledgement and Attribution Regarding Sources of Content
Some of the initial content on this page may be incorporated in part from copyleft sources in the public domain including wikis such as Wikipedia and AskDrWiki. Drug information for patients came from the The National Library of Medicine. Infectious disease information may have come from the Centers for Disease Control (CDC). Differential Diagnoses are drawn from clinicians as well as an amalgamation of 3 sources: 1.The Disease Database; 2. Kahan, Scott, Smith, Ellen G. In A Page: Signs and Symptoms. Malden, Massachusetts: Blackwell Publishing, 2004:3; 3. Sailer, Christian, Wasner, Susanne. Differential Diagnosis Pocket. Hermosa Beach, CA: Borm Bruckmeir Publishing LLC, 2002:7 .
