DIO2

Deiodinase, iodothyronine, type II
Identifiers
Symbols	DIO2 ; 5DII; D2; DIOII; SelY; TXDI2
External IDs	OMIM: 601413 MGI: 1338833 HomoloGene: 621 ChEMBL: 2054 GeneCards: DIO2 Gene
EC number	1.97.1.10
Gene ontology Molecular function • thyroxine 5'-deiodinase activity • selenium binding • ubiquitin protein ligase binding Cellular component • plasma membrane • membrane • integral component of membrane Biological process • selenocysteine incorporation • thyroid hormone generation • cellular nitrogen compound metabolic process • thyroid hormone metabolic process • hormone biosynthetic process • small molecule metabolic process • oxidation-reduction process Sources: Amigo / QuickGO
Orthologs
Species	Human	Mouse
Entrez	1734	13371
Ensembl	ENSG00000211448	ENSMUSG00000007682
UniProt	Q92813	Q9Z1Y9
RefSeq (mRNA)	NM_000793	NM_010050
RefSeq (protein)	NP_000784	NP_034180
Location (UCSC)	Chr 14: 80.2 – 80.39 Mb	Chr 12: 90.72 – 90.74 Mb
PubMed search	[1]	[2]

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

Function

The protein encoded by this gene belongs to the iodothyronine deiodinase family. It activates thyroid hormone by converting the prohormone 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 Graves' disease and thyroid 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 USP33.

See also

• Deiodinase