Thyroglobulin
Sign in to saveAlso known as uniprot:P01266, TG
Thyroglobulin (Tg) is a 660 kDa, dimeric glycoprotein produced by the follicular cells of the thyroid and used entirely within the thyroid gland. Tg is secreted and accumulated at hundreds of grams per litre in the extracellular compartment of the thyroid follicles, accounting for approximately half of the protein content of the thyroid gland. Human TG (hTG) is a homodimer of subunits each containing 2768 amino acids as synthesized (a short signal peptide of 19 amino acids may be removed from the N-terminus in the mature protein).
Protein · UniProt
Thyroglobulin
- Gene
- TG
- Organism
- Homo sapiens (Human)
- Length
- 2,768 aa
- Molecular mass
- 304,790 Da
- Evidence
- 1: Evidence at protein level
Acts as a substrate for the production of iodinated thyroid hormones thyroxine (T4) and triiodothyronine (T3) (PubMed:17532758, PubMed:32025030). The synthesis of T3 and T4 involves iodination of selected tyrosine residues of TG/thyroglobulin followed by their oxidative coupling in the thyroid follicle lumen (PubMed:32025030). Following TG re-internalization and lysosomal-mediated proteolysis, T3 and T4 are released from the polypeptide backbone leading to their secretion into the bloodstream (PubMed:32025030). One dimer produces 7 thyroid hormone molecules (PubMed:32025030)
Swiss-Prot (reviewed) · via UniProt
Clinical Trials
25 registered- COMPLETEDPostoperative HyperthyroidismHeidelberg University · NCT01095341
- COMPLETEDAssessment of Dried Blood Spot Thyroglobulin and Urinary Iodine Concentration in Pregnant WomenSwiss Federal Institute of Technology · NCT03176706
- COMPLETEDTG Gene Mutations and Congenital HypothyroidismUniversity of Sao Paulo · NCT00493103
- COMPLETEDPredicting Prognosis and Recurrence of Thyroid Cancer Via New Biomarkers, Urinary Exosomal Thyroglobulin and Galectin-3National Taiwan University Hospital · NCT03488134
- ACTIVE_NOT_RECRUITINGDiagnostic Accuracy of Fluorodeoxyglucose-18 PET in the Evaluation of RPTC With Patient's Raised Thyroglobulin LevelSuperior University · NCT07062211
- ACTIVE_NOT_RECRUITINGUrinary Exosomal Biomarkers of Thyroglobulin and Galectin-3 for Prognosis and Follow-up in Patients of Thyroid CancerNational Taiwan University Hospital · NCT04948437
~5 min read
Article
8 sectionsContents
- Function
- Clinical significance
- Half-life and clinical elevation
- Thyroglobulin antibodies
- Interactions
- References
- Further reading
- External links
Thyroglobulin (Tg) is a 660 kDa, dimeric glycoprotein produced by the follicular cells of the thyroid and used entirely within the thyroid gland. Tg is secreted and accumulated at hundreds of grams per litre in the extracellular compartment of the thyroid follicles, accounting for approximately half of the protein content of the thyroid gland. Human TG (hTG) is a homodimer of subunits each containing 2768 amino acids as synthesized (a short signal peptide of 19 amino acids may be removed from the N-terminus in the mature protein).
Thyroglobulin is in all vertebrates the main precursor to thyroid hormones, which are produced when thyroglobulin's tyrosine residues are combined with iodine and the protein is subsequently cleaved. Each thyroglobulin molecule contains approximately 16 tyrosine residues, but only around 10 of these are subject to iodination by thyroperoxidase in the follicular colloid. It takes two iodinated tyrosines to make a thyroid hormone molecule; therefore, each Tg molecule forms approximately 5 thyroid hormone molecules.