ID   IOD2_CHICK              Reviewed;         279 AA.
AC   Q9IAX2;
DT   16-AUG-2004, integrated into UniProtKB/Swiss-Prot.
DT   26-FEB-2008, sequence version 3.
DT   03-AUG-2022, entry version 95.
DE   RecName: Full=Type II iodothyronine deiodinase;
DE            EC=1.21.99.4;
DE   AltName: Full=5DII;
DE   AltName: Full=DIOII;
DE   AltName: Full=Type 2 DI;
DE   AltName: Full=Type-II 5'-deiodinase;
GN   Name=DIO2;
OS   Gallus gallus (Chicken).
OC   Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi;
OC   Archelosauria; Archosauria; Dinosauria; Saurischia; Theropoda;
OC   Coelurosauria; Aves; Neognathae; Galloanserae; Galliformes; Phasianidae;
OC   Phasianinae; Gallus.
OX   NCBI_TaxID=9031;
RN   [1] {ECO:0000305, ECO:0000312|EMBL:AAD33251.1}
RP   NUCLEOTIDE SEQUENCE [MRNA], FUNCTION, BIOPHYSICOCHEMICAL PROPERTIES, AND
RP   TISSUE SPECIFICITY.
RC   TISSUE=Embryo {ECO:0000269|PubMed:10318780}, and
RC   Pituitary {ECO:0000269|PubMed:10318780};
RX   PubMed=10318780; DOI=10.1074/jbc.274.20.13768;
RA   Gereben B., Bartha T., Tu H.M., Harney J.W., Rudas P., Larsen P.R.;
RT   "Cloning and expression of the chicken type 2 iodothyronine 5'-
RT   deiodinase.";
RL   J. Biol. Chem. 274:13768-13776(1999).
CC   -!- FUNCTION: Responsible for the deiodination of T4 (3,5,3',5'-
CC       tetraiodothyronine) into T3 (3,5,3'-triiodothyronine). Essential for
CC       providing the brain with appropriate levels of T3 during the critical
CC       period of development. {ECO:0000250|UniProtKB:Q92813,
CC       ECO:0000269|PubMed:10318780}.
CC   -!- CATALYTIC ACTIVITY:
CC       Reaction=3,3',5-triiodo-L-thyronine + A + H(+) + iodide = AH2 + L-
CC         thyroxine; Xref=Rhea:RHEA:19745, ChEBI:CHEBI:13193,
CC         ChEBI:CHEBI:15378, ChEBI:CHEBI:16382, ChEBI:CHEBI:17499,
CC         ChEBI:CHEBI:58448, ChEBI:CHEBI:533015; EC=1.21.99.4;
CC         Evidence={ECO:0000255|PROSITE-ProRule:PRU10107};
CC   -!- ACTIVITY REGULATION: Not inhibited by N(6)-propylthiouracil.
CC   -!- BIOPHYSICOCHEMICAL PROPERTIES:
CC       Kinetic parameters:
CC         KM=1.1 nM for thyroxine {ECO:0000269|PubMed:10318780};
CC         Vmax=0.34 pmol/min/mg enzyme {ECO:0000269|PubMed:10318780};
CC   -!- SUBCELLULAR LOCATION: Membrane {ECO:0000305}; Single-pass membrane
CC       protein {ECO:0000305}.
CC   -!- TISSUE SPECIFICITY: Highly expressed in liver and in various parts of
CC       the brain including telencephalon, hippocampus, cerebellum, and brain
CC       stem, and weakly expressed in thyroid, lung, and small intestine. Not
CC       detected in skeletal muscle, heart atria or ventricle, gizzard or
CC       kidney. {ECO:0000269|PubMed:10318780}.
CC   -!- SIMILARITY: Belongs to the iodothyronine deiodinase family.
CC       {ECO:0000255}.
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DR   EMBL; AF125575; AAD33251.1; -; mRNA.
DR   VEuPathDB; HostDB:geneid_373903; -.
DR   InParanoid; Q9IAX2; -.
DR   OrthoDB; 977776at2759; -.
DR   PhylomeDB; Q9IAX2; -.
DR   SABIO-RK; Q9IAX2; -.
DR   Proteomes; UP000000539; Unplaced.
DR   GO; GO:0016021; C:integral component of membrane; IEA:UniProtKB-KW.
DR   GO; GO:0004800; F:thyroxine 5'-deiodinase activity; IDA:UniProtKB.
DR   GO; GO:0042446; P:hormone biosynthetic process; IEA:UniProtKB-KW.
DR   GO; GO:0006590; P:thyroid hormone generation; IDA:UniProtKB.
DR   InterPro; IPR000643; Iodothyronine_deiodinase.
DR   InterPro; IPR008261; Iodothyronine_deiodinase_AS.
DR   InterPro; IPR036249; Thioredoxin-like_sf.
DR   PANTHER; PTHR11781; PTHR11781; 1.
DR   Pfam; PF00837; T4_deiodinase; 1.
DR   PIRSF; PIRSF001330; IOD; 1.
DR   SUPFAM; SSF52833; SSF52833; 1.
DR   PROSITE; PS01205; T4_DEIODINASE; 1.
PE   1: Evidence at protein level;
KW   Membrane; Oxidoreductase; Reference proteome; Selenocysteine;
KW   Thyroid hormones biosynthesis; Transmembrane; Transmembrane helix.
FT   CHAIN           1..279
FT                   /note="Type II iodothyronine deiodinase"
FT                   /id="PRO_0000154320"
FT   TRANSMEM        8..28
FT                   /note="Helical"
FT                   /evidence="ECO:0000255"
FT   ACT_SITE        132
FT   NON_STD         132
FT                   /note="Selenocysteine"
FT                   /evidence="ECO:0000303|PubMed:10318780"
FT   NON_STD         265
FT                   /note="Selenocysteine"
FT                   /evidence="ECO:0000303|PubMed:10318780"
SQ   SEQUENCE   279 AA;  31033 MW;  BC249728E2A8E9C1 CRC64;
     MGLLSADLLI TLQILPVFFS NCLFLALYDS VILLKHMVLF LSRSKSARGE WRRMLTSEGL
     RCVWNSFLLD AYKQVKLGGE APNSSVIHIA KGNDGSNSSW KSVGGKCGTK CHLLDFANSE
     RPLVVNFGSA TUPPFTSQLS AFSKLVEEFS GVADFLLVYI DEAHPSDGWA APGISPSSFE
     VKKHRNQEDR CAAAHQLLER FSLPPQCQVV ADCMDNNANV AYGVSFERVC IVQRQKIAYL
     GGKGPFFYNL QEVRLWLEQN FSKRUNPLST EDLSTDVSL