Topology of the main proteins involved in thyroid hormone synthesis <b>[Abstract in English]</b>

Abstract

Aims: To describe the topology of the main proteins related to thyroid synthesis through science articles from data bases. Source of data: Articles were retrieved from Pubmed and Scielo data base using the key-words related to the theme. Summary of the findings: Thyroid hormones are stored in the colloid, a substance found in the thyroid follicle and the site of the highest expressed glycoprotein of the thyroid cell, thyroglobulin, which is a 660 kDa single polypeptide protein, which gene is located on chromosome 8 (8q24.21-8q24.23) and contains 48 exons. The incorporation of iodine in tyrosine residues in thyroglobulin is catalyzed by another protein, thyroperoxidase. Thyroperoxidase requires hydrogen peroxide (H2O2) for the iodine oxidation in this reaction, and in the presence of sufficient cytosolic iodine, H2O2 is rate limiting in the biosynthesis of thyroid hormones. The generation of H2O2 is regulated by thyroid oxidase (ThOx or DuOx). Structural and topological studies of the proteins involved in thyroid hormone synthesis provide the basis for the best understanding of thyroid function at molecular and atomic resolution. Conclusions: Studies looking at structural and topological characteristics of thyroid proteins and their production can provide better understanding into the identification at molecular level of mutations and interactions with receptors, drugs and immunocomplexes, that have medical relevance.