DIO2

Type II iodothyronine deiodinase (iodothyronine 5'-deiodinase, iodothyronine 5'-monodeiodinase) is an is_associated_with::enzyme that in humans is encoded by the DIO2 is_associated_with::gene.

Function
The protein encoded by this gene belongs to the is_associated_with::iodothyronine deiodinase family. It activates is_associated_with::thyroid hormone by converting the is_associated_with::prohormone is_associated_with::thyroxine (T4) by outer ring deiodination (ORD) to bioactive 3,3',5-triiodothyronine (T3). It is highly expressed in the thyroid, and may contribute significantly to the relative increase in thyroidal T3 production in patients with is_associated_with::Graves' disease and thyroid is_associated_with::adenomas. This protein contains selenocysteine (Sec) residues 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. Alternative splicing results in multiple transcript variants encoding different isoforms.

Interactions
DIO2 has been shown to interact with is_associated_with::USP33.