Gene and Protein Information
Species	TM	AA	Chromosomal Location	Gene Symbol	Gene Name	Reference
Human	-	420	8p11.21	IDO2	indoleamine 2,3-dioxygenase 2
Mouse	-	405	8 A2	Ido2	indoleamine 2,3-dioxygenase 2
Rat	-	403	16q12.5	Ido2	indoleamine 2,3-dioxygenase 2

Previous and Unofficial Names

indoleamine 2 | INDOL1 | indoleamine-pyrrole 2,3 dioxygenase-like 1

Database Links
Alphafold	Q6ZQW0 (Hs), Q8R0V5 (Mm)
BRENDA	1.13.11.52
ChEMBL Target	CHEMBL3627587 (Hs), CHEMBL2189159 (Mm)
Ensembl Gene	ENSG00000188676 (Hs), ENSMUSG00000031549 (Mm), ENSRNOG00000025365 (Rn)
Entrez Gene	169355 (Hs), 209176 (Mm), 681319 (Rn)
Human Protein Atlas	ENSG00000188676 (Hs)
KEGG Enzyme	1.13.11.52
KEGG Gene	hsa:169355 (Hs), mmu:209176 (Mm), rno:681319 (Rn)
OMIM	612129 (Hs)
Pharos	Q6ZQW0 (Hs)
RefSeq Nucleotide	NM_194294 (Hs), NM_145949 (Mm)
RefSeq Protein	NP_919270 (Hs), NP_666061 (Mm)
UniProtKB	Q6ZQW0 (Hs), Q8R0V5 (Mm)
Wikipedia	IDO2 (Hs)

Enzyme Reaction
EC Number: 1.13.11.52 Description Reaction Reference D-tryptophan + O(2) <=> N-formyl-D-kynurenine L-tryptophan + O(2) <=> N-formyl-L-kynurenine

Download all structure-activity data for this target as a CSV file

Inhibitors
Key to terms and symbols	View all chemical structures	Click column headers to sort
Ligand Sp. Action Value Parameter Reference tryptanthrin 5i Hs Inhibition 6.0 pKi 2 ⤷ pKi 6.0 (Ki 9.7x10-7 M) [2] tryptanthrin 5i Hs Inhibition 5.7 – 6.3 pIC50 2 ⤷ pIC50 6.3 (IC50 4.5x10-7 M) [2] Description: Inhibition of enzyme activity when hIDO2 is expressed in U87 human glioblastoma cells. pIC50 5.7 (IC50 1.8x10-6 M) [2] Description: Inhibition of enzymatic activity of recombinant human IDO2. example 184 [WO2014186035] Hs Inhibition >6.0 pIC50 1 ⤷ pIC50 >6.0 (IC50 <1x10-6 M) [1] Description: Inhibition of recombinant human IDO2 (14-420)-mediated kynurenine formation from tryptophan, detected by LC/MS/MS analysis

Immunopharmacology Comments

IDO2 is an enzyme in the tryptophan-kynurenine pathway. It is expressed in immune cells (e.g. dendritic cells and monocytes) which suggests that it plays some role in immune function, but its precise function remains to be fully elucidated. Mice lacking Ido2 produce greater amounts of interleukin-6 (IL-6) and have elevated levels of activated (phosphorylated) Stat3 compared to wild type mice in response to LPS exposure [3]. Overexpression of Ido2 (in mouse macrophages) has the opposite effect, i.e. suppression of IL-6 production and Stat3 activation. These results suggest that pharmacological modulation of Ido2 could be exploited to regulate IL-6/Stat3 signalling as a mechanism to treat immune disorders.

Physiological Consequences of Altering Gene Expression
Ido2 knockout mice are more susceptible to LPS endotoxin-induced shock and death than wild type mice. Species:  Mouse Tissue:  Technique:  References:  3