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P55073 · IOD3_HUMAN

  • Protein
    Thyroxine 5-deiodinase
  • Gene
    DIO3
  • Status
    UniProtKB reviewed (Swiss-Prot)
  • Amino acids
  • Protein existence
    Evidence at protein level
  • Annotation score
    5/5

Function

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.

Caution

It is uncertain whether Met-1 or Met-27 is the initiator.

Catalytic activity

Kinetics

KM SUBSTRATE pH TEMPERATURE[C] NOTES EVIDENCE
4.3 nML-thyroxine
Vmax pH TEMPERATURE[C] NOTES EVIDENCE
1.4 pmol/min/mg

Features

Showing features for active site.

TypeIDPosition(s)Description
Active site170

GO annotations

AspectTerm
Cellular Componentendosome membrane
Cellular Componentintracellular membrane-bounded organelle
Cellular Componentplasma membrane
Molecular Functionthyroxine 5'-deiodinase activity
Molecular Functionthyroxine 5-deiodinase activity
Biological Processbrown fat cell proliferation
Biological Processhormone biosynthetic process
Biological Processpositive regulation of multicellular organism growth
Biological Processresponse to hypoxia
Biological Processretinal cone cell apoptotic process
Biological Processretinal cone cell development
Biological Processthyroid hormone catabolic process
Biological Processthyroid hormone metabolic process

Keywords

Enzyme and pathway databases

Names & Taxonomy

Protein names

  • Recommended name
    Thyroxine 5-deiodinase
  • EC number
  • Alternative names
    • 5DIII
    • DIOIII
    • Type 3 DI
    • Type III iodothyronine deiodinase

Gene names

    • Name
      DIO3
    • Synonyms
      ITDI3, TXDI3

Organism names

  • Taxonomic identifier
  • Taxonomic lineage
    Eukaryota > Metazoa > Chordata > Craniata > Vertebrata > Euteleostomi > Mammalia > Eutheria > Euarchontoglires > Primates > Haplorrhini > Catarrhini > Hominidae > Homo

Accessions

  • Primary accession
    P55073
  • Secondary accessions
    • G3XAM0
    • Q8WVN5

Proteomes

Organism-specific databases

Subcellular Location

Cell membrane
; Single-pass type II membrane protein
Endosome membrane
; Single-pass type II membrane protein

Features

Showing features for topological domain, transmembrane.

Type
IDPosition(s)Description
Topological domain1-44Cytoplasmic
Transmembrane45-67Helical; Signal-anchor for type II membrane protein
Topological domain68-304Extracellular

Keywords

Disease & Variants

Features

Showing features for mutagenesis.

TypeIDPosition(s)Description
Mutagenesis170Complete loss of activity.

Variants

We now provide the "Disease & Variants" viewer in its own tab.

The viewer provides 346 variants from UniProt as well as other sources including ClinVar and dbSNP.

Go to variant viewer

Organism-specific databases

Miscellaneous

Chemistry

Genetic variation databases

PTM/Processing

Features

Showing features for chain.

TypeIDPosition(s)Description
ChainPRO_00001543231-304Thyroxine 5-deiodinase

Proteomic databases

PTM databases

Expression

Tissue specificity

Expressed in placenta and several fetal tissues.

Gene expression databases

Organism-specific databases

Interaction

Subunit

Homodimer. May undergo minor heretodimerization with DIO1 and DIO2.

Protein-protein interaction databases

Miscellaneous

Family & Domains

Sequence similarities

Belongs to the iodothyronine deiodinase family.

Keywords

Phylogenomic databases

Family and domain databases

Sequence

  • Sequence status
    Complete
  • Length
    304
  • Mass (Da)
    33,947
  • Last updated
    2014-05-14 v4
  • MD5 Checksum
    40A1B8AA6D633FC8314F9F4F210148D3
MPRQATSRLVVGEGEGSQGASGPAATMLRSLLLHSLRLCAQTASCLVLFPRFLGTAFMLWLLDFLCIRKHFLGRRRRGQPEPEVELNSEGEEVPPDDPPICVSDDNRLCTLASLKAVWHGQKLDFFKQAHEGGPAPNSEVVLPDGFQSQHILDYAQGNRPLVLNFGSCTUPPFMARMSAFQRLVTKYQRDVDFLIIYIEEAHPSDGWVTTDSPYIIPQHRSLEDRVSAARVLQQGAPGCALVLDTMANSSSSAYGAYFERLYVIQSGTIMYQGGRGPDGYQVSELRTWLERYDEQLHGARPRRV

Computationally mapped potential isoform sequences

There is 1 potential isoform mapped to this entry

View all
EntryEntry nameGene nameLength
A0A8V8TPY2A0A8V8TPY2_HUMANDIO3131

Sequence caution

The sequence AAB35616.2 differs from that shown. Reason: Frameshift
The sequence AAH17717.2 differs from that shown. Reason: Erroneous initiation Truncated N-terminus.

Features

Showing features for sequence conflict, non-standard residue.

Type
IDPosition(s)Description
Sequence conflict29in Ref. 1; AAB35616
Sequence conflict79in Ref. 1; AAB35616
Non-standard residue170Selenocysteine

Keywords

Sequence databases

Nucleotide SequenceProtein SequenceMolecule TypeStatus
S79854
EMBL· GenBank· DDBJ
AAB35616.2
EMBL· GenBank· DDBJ
mRNA Frameshift
AL049836
EMBL· GenBank· DDBJ
-Genomic DNA No translation available.
BC017717
EMBL· GenBank· DDBJ
AAH17717.2
EMBL· GenBank· DDBJ
mRNA Different initiation

Genome annotation databases

Similar Proteins

Disclaimer

Any medical or genetic information present in this entry is provided for research, educational and informational purposes only. It is not in any way intended to be used as a substitute for professional medical advice, diagnosis, treatment or care. Our staff consists of biologists and biochemists that are not trained to give medical advice.
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