DIO3
Function
Responsible for the deiodination of T4 (3,5,3',5'-tetraiodothyronine) into RT3 (3,3',5'-triiodothyronine) and of T3 (3,5,3'-triiodothyronine) into T2 (3,3'-diiodothyronine). RT3 and T2 are inactive metabolites. May play a role in preventing premature exposure of developing fetal tissues to adult levels of thyroid hormones. Can regulate circulating fetal thyroid hormone concentrations throughout gestation. Essential role for regulation of thyroid hormone inactivation during embryological development.
Sequence Similarities
Belongs to the iodothyronine deiodinase family.
Tissue Specificity
Expressed in placenta and several fetal tissues.
Cellular localization
- Cell membrane
- Single-pass type II membrane protein
- Endosome membrane
- Single-pass type II membrane protein
Alternative names
ITDI3, TXDI3, DIO3, Thyroxine 5-deiodinase, 5DIII, DIOIII, Type 3 DI, Type III iodothyronine deiodinase