Thyroid peroxidase is a key enzyme in thyroid hormone biosynthesis and one of the major antigen in thyroid autoimmune disease. It is a type I glycosylated transmembrane protein localized to the apical part of thyroid follicular cells. It catalyzes iodide oxidation, iodination of tyrosine residues and coupling of iodotyrosines to generate the iodothyronines T4 and T3. The enzymatic reactions of TPO require the presence of iodide, H2O2 and thyroglobulin. The single-copy human gene, located on the short arm of chromosome 2p25 is comprised of 17 exons and 16 introns spanning about 150 kb. Its expression is under the control of thyroid-specific transcription factors such as TTF-1, TTF-2 and PAX. Multiple transcript variants encoding distinct isoforms have been identified for the protein.The pathological role of the protein has been identified in Grave's disease and total iodide organification defect (TIOD).
Intended for research use only. Not for use in human, therapeutic, or diagnostic applications.