Indoleamine 2,3-dioxygenase 2 (IDO2) is a protein that in humans is encoded by the IDO2 gene.[1]
Function
IDO2 (indolamine-2,3-dioxygenase) is an enzyme with protein size of 420 amino acids (47 kDa) that is used for catabolism of tryptophan. In organisms, other enzymes participate in L-tryptophan cleavage, namely IDO1 and TDO. Despite of IDO1 and IDO2 are closely related enzymes originating by gene duplication and sharing high level (43%) of sequence homology,[2][3] they differentiate by their kinetics, function and expression pattern. Genes encoding IDO1 and IDO2 have similar genomic structure and are situated closely to each other on chromosome 8.[4] IDO2 is produced in a very limited type of tissues as kidney, liver or antigen presenting cells.[5] IDO2 is less active on substrates of IDO1, better catabolizing other Trp derivates as 5-methoxytryptophan. There are several isoforms in population that comes from alternative splicing.[6] As well as IDO1, IDO2 has been reported in Treg differentiation in vitro,[7] suggesting a role in tolerance maintenance. Its expression has been found in several cancers, gastric, colon or renal tumores.[8]
↑Löb S, Königsrainer A, Zieker D, Brücher BL, Rammensee HG, Opelz G, Terness P (January 2009). "IDO1 and IDO2 are expressed in human tumors: levo- but not dextro-1-methyl tryptophan inhibits tryptophan catabolism". Cancer Immunology, Immunotherapy. 58 (1): 153–7. doi:10.1007/s00262-008-0513-6. PMID18418598.
Further reading
Ball HJ, Sanchez-Perez A, Weiser S, Austin CJ, Astelbauer F, Miu J, McQuillan JA, Stocker R, Jermiin LS, Hunt NH (July 2007). "Characterization of an indoleamine 2,3-dioxygenase-like protein found in humans and mice". Gene. 396 (1): 203–13. doi:10.1016/j.gene.2007.04.010. PMID17499941.
Metz R, Duhadaway JB, Kamasani U, Laury-Kleintop L, Muller AJ, Prendergast GC (August 2007). "Novel tryptophan catabolic enzyme IDO2 is the preferred biochemical target of the antitumor indoleamine 2,3-dioxygenase inhibitory compound D-1-methyl-tryptophan". Cancer Research. 67 (15): 7082–7. doi:10.1158/0008-5472.CAN-07-1872. PMID17671174.
Huttunen R, Syrjänen J, Aittoniemi J, Oja SS, Raitala A, Laine J, Pertovaara M, Vuento R, Huhtala H, Hurme M (February 2010). "High activity of indoleamine 2,3 dioxygenase enzyme predicts disease severity and case fatality in bacteremic patients". Shock. 33 (2): 149–54. doi:10.1097/SHK.0b013e3181ad3195. PMID19487973.
Cetindere T, Nambiar S, Santourlidis S, Essmann F, Hassan M (February 2010). "Induction of indoleamine 2, 3-dioxygenase by death receptor activation contributes to apoptosis of melanoma cells via mitochondrial damage-dependent ROS accumulation". Cellular Signalling. 22 (2): 197–211. doi:10.1016/j.cellsig.2009.09.013. PMID19799997.
Sørensen RB, Køllgaard T, Andersen RS, van den Berg JH, Svane IM, Straten P, Andersen MH (March 2011). "Spontaneous cytotoxic T-Cell reactivity against indoleamine 2,3-dioxygenase-2". Cancer Research. 71 (6): 2038–44. doi:10.1158/0008-5472.CAN-10-3403. PMID21406395.
Meininger D, Zalameda L, Liu Y, Stepan LP, Borges L, McCarter JD, Sutherland CL (December 2011). "Purification and kinetic characterization of human indoleamine 2,3-dioxygenases 1 and 2 (IDO1 and IDO2) and discovery of selective IDO1 inhibitors". Biochimica et Biophysica Acta. 1814 (12): 1947–54. doi:10.1016/j.bbapap.2011.07.023. PMID21835273.
