DIO3

Description

The DIO3 (iodothyronine deiodinase 3) is a protein-coding gene located on chromosome 14.

DIO3, also known as Type III iodothyronine deiodinase, is an enzyme encoded by the DIO3 gene in humans. It catalyzes the inactivation of thyroid hormone by converting the prohormone thyroxine (T4) and the bioactive hormone 3,3',5-triiodothyronine (T3) into inactive metabolites, 3,3',5'-triiodothyronine (RT3) and 3,3'-diiodothyronine (T2), respectively. DIO3 is highly expressed in the pregnant uterus, placenta, fetal and neonatal tissues, suggesting that it plays an essential role in the regulation of thyroid hormone inactivation during embryological development. The DIO3 gene was mapped to chromosome 14q32 using fluorescence in situ hybridization (FISH) in 1998. This protein contains a selenocysteine (Sec) residue, which is essential for efficient enzyme activity. It is encoded by the UGA codon, which normally signals translation termination. The 3' UTR of Sec-containing genes have a common stem-loop structure, the sec insertion sequence (SECIS), which is necessary for the recognition of UGA as a Sec codon rather than as a stop signal. DIO3 is part of the DLK1-Dio3 imprinting control region, which is involved in the epigenetic process that causes a subset of genes to be regulated based on their parental origin.

DIO3, also known as Type III iodothyronine deiodinase, converts the thyroid hormones T4 (thyroxine) into RT3 (reverse T3) and T3 (triiodothyronine) into T2 (diiodothyronine). RT3 and T2 are inactive forms of thyroid hormone. This inactivation is crucial during embryonic development as it prevents premature exposure of fetal tissues to adult levels of thyroid hormones. DIO3 regulates circulating fetal thyroid hormone concentrations throughout gestation, ensuring proper development.

DIO3 is also known as 5DIII, D3, DIOIII, TXDI3.

Associated Diseases

WES Whole Exome Sequencing