Trace derivatives of kynurenine potently activate the aryl hydrocarbon receptor (AHR)
Open accessAbstract
Cellular metabolites act as important signaling cues, but are subject to complex unknown chemistry. Kynurenine is a tryptophan metabolite that plays a crucial role in cancer and the immune system. Despite its atypical, non-ligand-like, highly polar structure, kynurenine activates the aryl hydrocarbon receptor (AHR), a PER, ARNT, SIM (PAS) family transcription factor that responds to diverse environmental and cellular ligands. The activity of kynurenine is increased 100-1000-fold by incubation or long-term storage and relies on the hydrophobic ligand-binding pocket of AHR, with identical structural signatures for AHR induction before and after activation. We purified trace-active derivatives of kynurenine and identified two novel, closely related condensation products, named trace-extended aromatic condensation products (TEACOPs), which are active at low picomolar levels. The synthesized compound for one of the predicted structures matched the purified compound in both chemical structure and AHR pharmacology. Our study provides evidence that kynurenine acts as an AHR pro-ligand, which requires novel chemical conversions to act as a receptor agonist.
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Recent docking studies allowed prediction of the binding modes of several AhR ligands and led to the discovery of novel AhR agonists and SAhRMs.
“On the basis of these novel approaches, recent docking studies not only allowed prediction of the binding modes of several AhR ligands but also led to the discovery of novel AhR agonists and SAhRMs25,27–30.”
From Modeling the binding of diverse ligands within the Ah receptor ligand binding domain (2019) · cites this paper as [29]
The Modeling section (page not available) describes docking several AHR ligands to predict their interactions. The Discussion (page not available) reports discovery of two potent new AHR-activating compounds, but attributes that discovery to a combination of methods rather than docking alone. Our copy does not identify the compounds as SAhRMs. (LLM, conf=0.86)
Experimental — accuracy not yet measuredSuch ligands may function as pro-ligands through conversion to real AHR ligands with higher binding potencies, as exemplified by kynurenine and its trace derivatives.
“They may rather function as “pro-ligands” through further conversion to “real” AHR ligands with much higher binding potencies, as exemplified by kynurenine and its trace derivatives52.”
From Structural basis for the ligand-dependent activation of heterodimeric AHR-ARNT complex (2025) · cites this paper as [52]
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“Similarly, the Trp metabolite Kyn is the source of trace-extended aromatic condensation products (TEACOPs), which are highly potent AHR agonists 68 .”
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“Kynurenine (and its metabolites), FICZ and ITE are high affinity endogenous agonists that cause AhR activation in pM to nM concentrations [2,7,44].”
BackgroundDu, W., Jiang, S., Yin, S., Wang, R., Zhang, C., Yin, B., Li, J., Li, L., Qi, N., Zhou, Y. Q., et al. (2024) · Proceedings of the National Academy of Sciences · doi:10.1073/pnas.2400385121 · Cited by 78 · see citing works
“In addition, kynurenic acid was reported to activate AhR in immune cells ( 34 ), while restoring AhR signaling exert beneficial effects on metabolic syndrome ( 35 ).”
Tryptophan: From Diet to Cardiovascular Diseases
Melhem, N. J., & Taleb, S. (2021) · International Journal of Molecular Sciences · doi:10.3390/ijms22189904 · Cited by 72 · see citing works
“Recently, two trace-active derivatives of Kyn named trace-extended aromatic condensation products (TEACOPs) have been identified and considered as high affinity AHR ligands [61].”
BackgroundLigands and agonists of the aryl hydrocarbon receptor AhR: Facts and myths
Sládeková, L., Mani, S., & Dvořák, Z. (2023) · Biochemical Pharmacology · doi:10.1016/j.bcp.2023.115626 · Cited by 70 · see citing works
Insights into teleost interferon-gamma biology: An update
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Kynurenine pathway and human systems
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Structural basis for the ligand-dependent activation of heterodimeric AHR-ARNT complex
Diao, X., Shang, Q., Guo, M., Huang, Y., Zhang, M., Chen, X., Liang, Y., Sun, X., Zhou, F., Zhuang, J., et al. (2025) · Nature communications · doi:10.1038/s41467-025-56574-7 · Cited by 72 · see citing works
“They may rather function as “ pro-ligands ” through further conversion to “ real ” AHR ligands with much higher binding potencies, as exempli fi ed by kynurenine and its trace derivatives 52 .”
The Kynurenine Pathway and Indole Pathway in Tryptophan Metabolism Influence Tumor Progression
Lu, Z., Zhang, C., Zhang, J., Su, W., Wang, G., & Wang, Z. (2025) · Cancer Medicine · doi:10.1002/cam4.70703 · Cited by 74 · see citing works
Feng, X., Liao, D., Liu, D., Ping, A., Li, Z., & Bian, J. (2020) · Journal of Medicinal Chemistry · doi:10.1021/acs.jmedchem.0c00925 · Cited by 62 · see citing works
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Guenin‐Macé, L., Morel, J., Doisne, J., Schiavo, A., Boulet, L., Mayau, V., Gonçalves, P., Duchatelet, S., Hovnanian, A., Bondet, V., et al. (2020) · JCI Insight · doi:10.1172/jci.insight.140598 · Cited by 60 · see citing works
“Known agonists of AHR include Kyn, a low-affinity ligand whose physiological relevance is doubtful (42), and indole derivatives originating from bacterial degradation of Trp.”
BackgroundPark, A., Yang, Y., Lee, Y., Kim, M. S., Park, Y., Jung, H., Kim, T., Lee, H. G., Choi, I., & Yoon, S. R. (2019) · Journal of Clinical Medicine · doi:10.3390/jcm8060842 · Cited by 62 · see citing works
“Kynurenine enters the cells via AHR (aryl hydrocarbon receptor) [13].”
BackgroundTanaka, M., Szabó, Á., & Vécsei, L. (2024) · International Journal of Molecular Sciences · doi:10.3390/ijms252312767 · Cited by 62 · see citing works
“Over the decades, it has become clear that certain KYN metabolites, such as KYN, KYNA, AA, XA, and CA function as ligands for the AhR, a key transcription factor involved in immune regulation [286–288].”
Metabolic modeling reveals a multi-level deregulation of host-microbiome metabolic networks in IBD
Taubenheim, J., Kadibalban, A. S., Zimmermann, J., Taubenheim, C., Tran, F., Schreiber, S., Rosenstiel, P. C., Aden, K., & Kaleta, C. (2025) · Nature Communications · doi:10.1038/s41467-025-60233-2 · Cited by 64 · see citing works
“Interestingly, indole is an anti-in fl ammatory agonist of the aryl hydrocarbon receptor and has been reported as bene fi cial during colonic in fl ammation 54 – 57 .”
Immunomodulatory Effects of Genetic Alterations Affecting the Kynurenine Pathway
Boros, F. A., & Vécsei, L. (2019) · Frontiers in Immunology · doi:10.3389/fimmu.2019.02570 · Cited by 58 · see citing works
Iizuka, T., Yin, P., Zuberi, A., Kujawa, S. A., Coon, J. S., Björvang, R. D., Damdimopoulou, P., Pacyga, D. C., Strakovsky, R. S., Flaws, J. A., et al. (2022) · Proceedings of the National Academy of Sciences · doi:10.1073/pnas.2208886119 · Cited by 57 · see citing works
Indole scaffolds as a promising class of the aryl hydrocarbon receptor ligands
Dvořák, Z., Poulíková, K., & Mani, S. (2021) · European Journal of Medicinal Chemistry · doi:10.1016/j.ejmech.2021.113231 · Cited by 56 · see citing works
Kynurenine induces T cell fat catabolism and has limited suppressive effects in vivo
Siska, P. J., Jiao, J., Matos, C., Singer, K., Berger, R. S., Dettmer, K., Oefner, P. J., Cully, M. D., Wang, Z., QuinnIII, W. J., et al. (2021) · EBioMedicine · doi:10.1016/j.ebiom.2021.103734 · Cited by 56 · see citing works
“However, there are also structural chemistry data that suggest Lkynurenine to be a weak binding agonist to AhR, and that more potent AhR agonists can be formed from L-kynurenine through aromatic condensation [55].”
BackgroundLi, L., Dai, Y., & Xia, Y. (2022) · European Journal of Medicinal Chemistry · doi:10.1016/j.ejmech.2022.114845 · Cited by 56 · see citing works
The Role of the Kynurenine/AhR Pathway in Diseases Related to Metabolism and Cancer
Shadboorestan, A., Koual, M., Dairou, J., & Coumoul, X. (2023) · International Journal of Tryptophan Research · doi:10.1177/11786469231185102 · Cited by 56 · see citing works
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How Ah Receptor Ligand Specificity Became Important in Understanding Its Physiological Function
Murray, I. A., & Perdew, G. H. (2020) · International Journal of Molecular Sciences · doi:10.3390/ijms21249614 · Cited by 52 · see citing works
“Recent evidence has cast doubt upon the veracity of kynurenine as a bone fide AHR ligand, rather in vitro/modeling data is presented suggesting that kynurenine is a proligand which can undergo condensation reactions to generate so-called trace-extended aromatic condensation products (TEACOPs) with greatly enhanced AHR…”
BackgroundMetabolite activation of tumorigenic signaling pathways in the tumor microenvironment
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The aryl hydrocarbon receptor is a tumor suppressor–like gene in glioblastoma
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“Kynurenine activity as an AhR agonist is cell context– dependent (26 –36), and a recent study showed that, under storage conditions, the AhR activity of kynurenine can be increased by up to a 1000-fold because of formation of potent polycyclic condensation products (35).”
BackgroundYan, B., Mao, X., Hu, S., Wang, S., Liu, X., & Sun, J. (2023) · International Immunopharmacology · doi:10.1016/j.intimp.2023.110166 · Cited by 42 · see citing works
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“Kynurenic acid activates the AHR and may be responsible for the apparent activation by kynurenine (Sadik et al., 2020 ), although spontaneous changes in kynurenine structure can re - portedly generate compounds with picomolar potency (Seok et al., 2018 ).”
Álvarez-Rodríguez, M., Pereiro, P., Reyes‐López, F. E., Tort, L., Figueras, A. J., & Novoa, B. (2018) · Frontiers in Immunology · doi:10.3389/fimmu.2018.01575 · Cited by 40 · see citing works
The IDO Metabolic Trap Hypothesis for the Etiology of ME/CFS
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“For example, kynurenine is spontaneously converted to trace condensation products called TEACOPs that are potent activators of the aryl hydrocarbon receptor (AHR), a transcription factor that controls the development of Treg cells [53].”
BackgroundAHR signaling in the development and function of intestinal immune cells and beyond
Cervantes‐Barragán, L., & Colonna, M. (2018) · Seminars in Immunopathology · doi:10.1007/s00281-018-0694-9 · Cited by 39 · see citing works
“Although kynurenine is a low-affinity AHR agonist, two novel condensation products derived from kynurenine, called trace extended aromatic condensation products (TEACOPs), were recently shown to be active at low picomolar levels; this suggests that kynurenine may act as an AHR pro-ligand that requires a yet undefined…”
BackgroundZuo, X., Zhang, T., Dong, X., Liu, J., & Liu, Y. (2025) · Food Research International · doi:10.1016/j.foodres.2025.115766 · Cited by 38 · see citing works
Serotonin Modulates AhR Activation by Interfering with CYP1A1-Mediated Clearance of AhR Ligands
Manzella, C. R., Ackerman, M. T., Singhal, M., Ticho, A. L., Ceh, J., Alrefai, W. A., Saksena, S., Dudeja, P. K., & Gill, R. K. (2019) · Cellular Physiology and Biochemistry · doi:10.33594/000000209 · Cited by 37 · see citing works
“Other endogenous ligands include both bacteria-derived indoles and condensation products of the TRP-derived metabolite kynurenine [13, 14].”
BackgroundAryl Hydrocarbon Receptor Signalling in the Control of Gut Inflammation
Marafini, I., Monteleone, I., Laudisi, F., & Monteleone, G. (2024) · International Journal of Molecular Sciences · doi:10.3390/ijms25084527 · Cited by 39 · see citing works
“AHR agonists can also derive from dietary tryptophan, a ubiquitous dietary amino acid that is metabolized by commensal microorganisms (e.g., Lactobacillus reuteri ) [35,36].”
BackgroundProgress in the development of kynurenine and quinoline-3-carboxamide-derived drugs
Boros, F. A., & Vécsei, L. (2020) · Expert Opinion on Investigational Drugs · doi:10.1080/13543784.2020.1813716 · Cited by 36 · see citing works
Dopamine is an aryl hydrocarbon receptor agonist
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Self-citationAryl Hydrocarbon Receptor Plasma Agonist Activity Correlates With Disease Activity in Progressive MS
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Aryl hydrocarbon receptor: From pathogenesis to therapeutic targets in aging-related tissue fibrosis
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The Aryl Hydrocarbon Receptor (AHR): Peacekeeper of the Skin
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“Instead, kynurenine may act as a pro-ligand, and its derivatives or Trace-Extended Aromatic Condensation Products (TEACOPs) are the actual AHR ligands, capable of eliciting a response at even picomolar concentrations [53].”
Deciphering the roles of aryl hydrocarbon receptor (AHR) in regulating carcinogenesis
Chong, Z. X., Yong, C. Y., Ong, H. K., Yeap, S. K., & Ho, W. Y. (2023) · Toxicology · doi:10.1016/j.tox.2023.153596 · Cited by 32 · see citing works
Targeting amino acid-metabolizing enzymes for cancer immunotherapy
Grobben, Y. (2024) · Frontiers in Immunology · doi:10.3389/fimmu.2024.1440269 · Cited by 33 · see citing works
Tryptophan and Its Metabolites in Lung Cancer: Basic Functions and Clinical Significance
Li, C., & Zhao, H. (2021) · Frontiers in Oncology · doi:10.3389/fonc.2021.707277 · Cited by 30 · see citing works
“Interestingly, KYN can directly bind and activate the AhR, with a high affinity at low picomolar levels (95).”
BackgroundA microbially produced AhR ligand promotes a Tph1-driven tolerogenic program in multiple sclerosis
Zelante, T., Paolicelli, G., Fallarino, F., Gargaro, M., Vascelli, G., Zuani, M. D., Frič, J., Lázničková, P., Kohoutková, M. H., Macchiarulo, A., et al. (2024) · Scientific Reports · doi:10.1038/s41598-024-57400-8 · Cited by 31 · see citing works
“The AhR mutation H285A, is known to also disrupt FICZ and L-Kyn binding to the the AhR ligand-binding pocket 24 .”
BackgroundDiscrete interplay of gut microbiota L-tryptophan metabolites in host biology and disease
Ranhotra, H. S. (2023) · Molecular and Cellular Biochemistry · doi:10.1007/s11010-023-04867-0 · Cited by 27 · see citing works
“Seok et al.observed that the AhR activity of kynurenine increases 100–1000-fold with incubation or during long-term storage [129].”
Kynurenine Relaxes Arteries of Normotensive Women and Those With Preeclampsia
Worton, S. A., Pritchard, H. A. T., Greenwood, S. L., Alakrawi, M., Heazell, A. E. P., Wareing, M., Greenstein, A. S., & Myers, J. (2021) · Circulation Research · doi:10.1161/circresaha.120.317612 · Cited by 27 · see citing works
Boyt, D., Boland, L. K., Burand, A. J., Brown, A. J., & Ankrum, J. A. (2020) · Journal of The Royal Society Interface · doi:10.1098/rsif.2019.0815 · Cited by 26 · see citing works
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Decreased IDO1-dependent tryptophan metabolism in aged lung during influenza
Cho, S. J., Hong, K. S., Schenck, E. J., Lee, S. F., Harris, R. M., Yang, J., Choi, A. M. K., & Stout-Delgado, H. W. (2020) · European Respiratory Journal · doi:10.1183/13993003.00443-2020 · Cited by 22 · see citing works
“Recent work has illustrated that kynurenine can bind to aryl hydrocarbon receptor and result in heightened kynurenine activity [21].”
BackgroundCirac, A., Tsaktanis, T., Beyer, T., Linnerbauer, M., Andlauer, T. F. M., Grummel, V., Nirschl, L., Lößlein, L., Quintana, F. J., Hemmer, B., et al. (2021) · Neurology Neuroimmunology & Neuroinflammation · doi:10.1212/nxi.0000000000001043 · Cited by 22 · see citing works
The aryl hydrocarbon receptor as a model PAS sensor
Vazquez-Rivera, E., Rojas, B. L., Parrott, J. C., Shen, A. L., Xing, Y., Carney, P. R., & Bradfield, C. A. (2021) · Toxicology Reports · doi:10.1016/j.toxrep.2021.11.017 · Cited by 21 · see citing works
Self-citationThe kynurenine pathway; A new target for treating maternal features of preeclampsia?
Worton, S. A., Greenwood, S. L., Wareing, M., Heazell, A. E. P., & Myers, J. (2019) · Placenta · doi:10.1016/j.placenta.2019.04.007 · Cited by 22 · see citing works
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Summers, B. S., Broome, S. T., Pang, T. W. R., Mundell, H. D., Belic, N. K., Tom, N., Ng, M. L., Yap, M. L., Sen, M. K., Sedaghat, S., et al. (2024) · International Journal of Tryptophan Research · doi:10.1177/11786469241248287 · Cited by 20 · see citing works
“94 AhR activation regulates a diverse set of biological processes including metabolising environmental toxins, cellular oxidation/antioxidation and immune regulation in the CNS. 95 Immune regulation mediated by AhR can result in both anti-and pro-inflammatory effects, 95-97 as previously reviewed.”
BackgroundThe aryl hydrocarbon receptor: A diagnostic and therapeutic target in glioma
Lim, T. X., Ahamed, M., & Reutens, D. C. (2021) · Drug Discovery Today · doi:10.1016/j.drudis.2021.09.021 · Cited by 20 · see citing works
Regulation of host immune responses by Lactobacillus through aryl hydrocarbon receptors
Huang, Z., Xie, L., & Huang, Z. (2023) · Medicine in Microecology · doi:10.1016/j.medmic.2023.100081 · Cited by 19 · see citing works
IDO-triggered swellable polymeric micelles for IDO inhibition and targeted cancer immunotherapy.
Park, J., Nah, Y., & Kim, W. J. (2023) · Journal of Controlled Release · doi:10.1016/j.jconrel.2023.09.050 · Cited by 19 · see citing works
Immunomodulatory actions of a kynurenine-derived endogenous electrophile
Carreño, M., Pires, M. F., Woodcock, S. R., Brzóska, T., Ghosh, S., Salvatore, S. R., Chang, F., Khoo, N. K. H., Dunn, M., Connors, N., et al. (2022) · Science Advances · doi:10.1126/sciadv.abm9138 · Cited by 18 · see citing works
Lu, Z., Hsu, C., Younis, N. K., Mustafa, M. A., Matveeva, E. A., Al-Juboory, Y. H. O., Adil, M., Athab, Z. H., & Abdulraheem, M. N. (2024) · Apmis · doi:10.1111/apm.13401 · Cited by 19 · see citing works
“Tryptophan metabolism through indolea-mine 2,3-dioxygenase (IDO) yields L-kynurenine and kynurenic acid, both of which have the potential to activate AhR within immune cells [172, 173].”
BackgroundExploring tryptophan metabolism in cardiometabolic diseases
Mouttoulingam, N., & Taleb, S. (2024) · Trends in Endocrinology and Metabolism · doi:10.1016/j.tem.2024.11.009 · Cited by 17 · see citing works
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“KYN is a moderate-affinity ligand of AHR and is sufficient to activate the transcriptional activity of genes downstream of AHR [48,49].”
BackgroundAryl hydrocarbon receptor role in chronic inflammatory skin diseases: a narrative review
Dec, M., & Arasiewicz, H. (2024) · Advances in Dermatology and Allergology · doi:10.5114/ada.2023.135617 · Cited by 18 · see citing works
“…modest affinity, the physiological implications of which remain uncertain and indole derivatives originating from bacterial degradation of Trp. Guenin-Macé et al. made metabolomic analysis and among bacterial metabolites of Trp detected indole-3-acetic acid (IAA)- recognized AHR agonist [58, 59].”
BackgroundInhibition of tryptophan 2,3-dioxygenase impairs DNA damage tolerance and repair in glioma cells
Reed, M. R., Maddukuri, L., Ketkar, A. D., Byrum, S. D., Zafar, M. K., Bostian, A. C. L., Tackett, A. J., & Eoff, R. L. (2021) · NAR Cancer · doi:10.1093/narcan/zcab014 · Cited by 16 · see citing works
The effect of environmental pollution on immune evasion checkpoints of SARS-CoV-2
Engin, A. B., Engin, A., & Engin, A. (2020) · Environmental Toxicology and Pharmacology · doi:10.1016/j.etap.2020.103520 · Cited by 15 · see citing works
Further characterization of tryptophan metabolism and its dysregulation in fibroids
Chuang, T., Quintanilla, D., Boos, D., & Khorram, O. (2022) · F&S Science · doi:10.1016/j.xfss.2022.04.005 · Cited by 15 · see citing works
Maguire, M., Larsen, M. C., Vezina, C. M., Quadro, L., Kim, Y., Tanumihardjo, S. A., & Jefcoate, C. R. E. (2020) · PLoS ONE · doi:10.1371/journal.pone.0228436 · Cited by 13 · see citing works
“Cyp1b1 metabolizes diverse natural substrates in different cell types, including estradiol in vascular cells [20, 21], arachidonic acid in macrophage [22] and natural ligands for the AhR [23, 24].”
BackgroundSelf-citationChemical sensing in development and function of intestinal lymphocytes
Cervantes‐Barragán, L., & Colonna, M. (2018) · Current Opinion in Immunology · doi:10.1016/j.coi.2018.01.004 · Cited by 12 · see citing works
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Self-citationAi, Y., Wang, B., Xiao, S., Luo, S., & Wang, Y. (2021) · International Journal of Molecular Sciences · doi:10.3390/ijms222212428 · Cited by 11 · see citing works
“Moreover, kynurenine is an endogenous ligand that promotes tumor proliferation; it can bind to and activate aryl hydrocarbon receptor (AHR) to exert biological effects, both of which contribute to the occurrence and development of tumors [25].”
BackgroundTDO2 promotes bladder cancer progression via AhR-mediated SPARC/FILIP1L signaling
Ding, X., Jin, Y., Shi, X., Wang, Y., Jin, Z., Yin, L., Gao, S., Lei, Y., & Yang, J. (2024) · Biochemical Pharmacology · doi:10.1016/j.bcp.2024.116172 · Cited by 10 · see citing works
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Tryptophan Metabolism Through the Kynurenine Pathway in Glial Cells
Argolo, D. S., de Oliveira, L. M. G., Guillemin, G. J., Barreto, G. E., Butt, A. M., Costa, S. L., & Costa, M. D. F. D. (2025) · Neuroglia · doi:10.3390/neuroglia6010014 · Cited by 10 · see citing works
“It is well established that KYN concentrations below the picomolar level are sufficient to bind to AhRs [64].”
The role of aryl hydrocarbon receptor in antiviral immunity: a focus on RNA viruses
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“…which spontaneously converts in solution to yield trace-extended aromatic condensation products (teAcOPs) that are picomolar agonists of the AhR (Seok et al. 2018). it is known that iDO-1 is regulated by iFN-β, iFN-γ and other cytokines, and by nitric oxide, which participate in host response…”
Mosa, F. E. S., El‐Kadi, A. O. S., & Barakat, K. (2022) · Journal of Molecular Graphics and Modelling · doi:10.1016/j.jmgm.2022.108339 · Cited by 10 · see citing works
Palzkill, V. R., Tan, J., Yang, Q., Morcos, J., Laitano, O., & RYAN, T. E. (2023) · American Journal of Physiology-Heart and Circulatory Physiology · doi:10.1152/ajpheart.00530.2023 · Cited by 9 · see citing works
- Authors
- Seok, S.-H., Ma, Z.-X., Feltenberger, J. B., Chen, H., Chen, H., Scarlett, C., Lin, Z., Satyshur, K. A., Cortopassi, M., Jefcoate, C. R., Ge, Y., Tang, W., Bradfield, C. A., & Xing, Y.
- Affiliations
- University of Wisconsin–Madison (US)
- Corresponding author
- Xing, Yongna
- ORCID
- Venue
- Journal of Biological Chemistry
- Publisher
- Elsevier BV
- Published
- 2018-02
- Volume
- 293
- Issue
- 6
- Pages
- 1994-2005
- ISSN
- 0021-9258 (ISSN-L)
- PMC
- PMC5808761
- OpenAlex
- W2779643604
- Cited by
- 157
- References
- 48
- Citations by year
- 2026: 15 · 2025: 27 · 2024: 16 · 2023: 19 · 2022: 16 · 2021: 16 · 2020: 22 · 2019: 16 · 2018: 10
- FWCI
- 4.37
- Type
- journal article
- Language
- en
- Open access
- hybrid
- doi.org
- Licence
- Locations
- Journal of Biological Chemistry (publishedVersion, cc-by)
- Europe PMC (PubMed Central) (publishedVersion)
- PubMed Central (publishedVersion)
- PubMed (publishedVersion)
- Funders
- DH National Institute for Health Research (NIHR) (R01 GM096060, R35028377)
- Topics
- Life Sciences › Neuroscience › Biological Psychiatry › Tryptophan and brain disorders
- Physical Sciences › Environmental Science › Health, Toxicology and Mutagenesis › Toxic Organic Pollutants Impact
- Life Sciences › Pharmacology, Toxicology and Pharmaceutics › Pharmacology › Pharmacogenetics and Drug Metabolism
- Keywords
- kynurenine, aryl hydrocarbon receptor, tryptophan metabolism, AhR activation, binding pocket, condensation products, transcription factor activation
- MeSH terms
- Animals, Binding Sites, Kinetics, Kynurenine, Ligands, Molecular Structure, Receptors, Aryl Hydrocarbon, Mice
About these checks
Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.
Statistics and arithmetic are recomputed, not judged.
Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.
What counts as a claim ›How we measure confidence ›How we check this ›
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