Gene Symbol: nr1i2
Description: nuclear receptor subfamily 1, group I, member 2
Alias: PXR, nuclear receptor subfamily 1 group I member 2, pregnane X receptor
Species: zebrafish

Top Publications

  1. Bresolin T, de Freitas Rebelo M, Celso Dias Bainy A. Expression of PXR, CYP3A and MDR1 genes in liver of zebrafish. Comp Biochem Physiol C Toxicol Pharmacol. 2005;140:403-7 pubmed
    The Pregnane X Receptor (PXR) is a nuclear receptor involved in the transcriptional regulation of drug-metabolizing enzymes and transporters...
  2. Ekins S, Reschly E, Hagey L, Krasowski M. Evolution of pharmacologic specificity in the pregnane X receptor. BMC Evol Biol. 2008;8:103 pubmed publisher
    The pregnane X receptor (PXR) shows the highest degree of cross-species sequence diversity of any of the vertebrate nuclear hormone receptors...
  3. Krasowski M, Yasuda K, Hagey L, Schuetz E. Evolution of the pregnane x receptor: adaptation to cross-species differences in biliary bile salts. Mol Endocrinol. 2005;19:1720-39 pubmed
    The pregnane X receptor (PXR) regulates the metabolism and elimination of bile salts, steroids, and xenobiotics...
  4. Krasowski M, Yasuda K, Hagey L, Schuetz E. Evolutionary selection across the nuclear hormone receptor superfamily with a focus on the NR1I subfamily (vitamin D, pregnane X, and constitutive androstane receptors). Nucl Recept. 2005;3:2 pubmed
    ..selection of most NR genes, with two possible exceptions being the ligand-binding domains (LBDs) of the pregnane X receptor (PXR, NR1I2) and the constitutive androstane receptor (CAR, NR1I3), two proteins involved in the regulation ..
  5. Moore L, Maglich J, McKee D, Wisely B, Willson T, Kliewer S, et al. Pregnane X receptor (PXR), constitutive androstane receptor (CAR), and benzoate X receptor (BXR) define three pharmacologically distinct classes of nuclear receptors. Mol Endocrinol. 2002;16:977-86 pubmed publisher
    ..of nuclear receptors contains a phylogenetically diverse array of receptors related to the mammalian pregnane X receptor (PXR) (NR1I2) and constitutive androstane receptor (CAR) (NR1I3)...
  6. Reschly E, Bainy A, Mattos J, Hagey L, Bahary N, Mada S, et al. Functional evolution of the vitamin D and pregnane X receptors. BMC Evol Biol. 2007;7:222 pubmed
    The vitamin D receptor (VDR) and pregnane X receptor (PXR) are nuclear hormone receptors of the NR1I subfamily that show contrasting patterns of cross-species variation...
  7. Bainy A, Kubota A, Goldstone J, Lille Lang y R, Karchner S, Celander M, et al. Functional characterization of a full length pregnane X receptor, expression in vivo, and identification of PXR alleles, in zebrafish (Danio rerio). Aquat Toxicol. 2013;142-143:447-57 pubmed publisher
    The pregnane X receptor (PXR) (nuclear receptor NR1I2) is a ligand activated transcription factor, mediating responses to diverse xenobiotic and endogenous chemicals. The properties of PXR in fish are not fully understood...
  8. Jeon H, Lee Y, Kim M, Choi S, Park B, Lee S. Integrated biomarkers induced by chlorpyrifos in two different life stages of zebrafish (Danio rerio) for environmental risk assessment. Environ Toxicol Pharmacol. 2016;43:166-74 pubmed publisher
    ..The expression level of NR1I2, a CYP gene transcriptional regulator, UGT1a1, and MDR1 were all up-regulated in the CHL-treated embryos...
  9. Kubota A, Bainy A, Woodin B, Goldstone J, Stegeman J. The cytochrome P450 2AA gene cluster in zebrafish (Danio rerio): expression of CYP2AA1 and CYP2AA2 and response to phenobarbital-type inducers. Toxicol Appl Pharmacol. 2013;272:172-9 pubmed publisher
    ..The results identify a CYP2 subfamily in zebrafish that includes genes apparently induced by PB-type chemicals and PXR agonists, the first concrete in vivo evidence for a PB-type response in fish.

More Information


  1. Cunha V, Rodrigues P, Santos M, Moradas Ferreira P, Ferreira M. Danio rerio embryos on Prozac - Effects on the detoxification mechanism and embryo development. Aquat Toxicol. 2016;178:182-9 pubmed publisher
    ..e., abcb4, abcc1, abcc2, abcg2, cyp1a, cyp3a65, gst, sod, cat, ahr, pxr, ppar?, ppar?, ppar?, rxraa, rxrab, rxrbb, rxrga, rxrgb, raraa, rarab, rarga evaluated...
  2. Krasowski M, Ai N, Hagey L, Kollitz E, Kullman S, Reschly E, et al. The evolution of farnesoid X, vitamin D, and pregnane X receptors: insights from the green-spotted pufferfish (Tetraodon nigriviridis) and other non-mammalian species. BMC Biochem. 2011;12:5 pubmed publisher
    The farnesoid X receptor (FXR), pregnane X receptor (PXR), and vitamin D receptor (VDR) are three closely related nuclear hormone receptors in the NR1H and 1I subfamilies that share the property of being activated by bile salts...
  3. Fernandez I, Santos A, Cancela M, Laizé V, Gavaia P. Warfarin, a potential pollutant in aquatic environment acting through Pxr signaling pathway and ?-glutamyl carboxylation of vitamin K-dependent proteins. Environ Pollut. 2014;194:86-95 pubmed publisher
    ..Expression of pregnane X receptor (pxr), the nuclear receptor binding vitamin K, was ubiquitous in zebrafish and suggests that warfarin ..
  4. Fidler A, Holland P, Reschly E, Ekins S, Krasowski M. Activation of a tunicate (Ciona intestinalis) xenobiotic receptor orthologue by both natural toxins and synthetic toxicants. Toxicon. 2012;59:365-72 pubmed publisher
    ..The solitary tunicate Ciona intestinalis (Phylum Chordata) genome encodes an orthologue of the vertebrate pregnane X receptor (PXR) and vitamin D receptor (VDR), here denoted CiVDR/PXR?...
  5. Li X, Ma J, Fang Q, Li Y. Transcription alterations of microRNAs, cytochrome P4501A1 and 3A65, and AhR and PXR in the liver of zebrafish exposed to crude microcystins. Toxicon. 2013;73:17-22 pubmed publisher
    ..cytochromes P450s CYP1A1 and CYP3A65, and their receptors, aryl hydrocarbon receptor (AhR, for CYP1A1) and pregnane X receptor (PXR, for CYP3A65), in the liver of zebrafish were evaluated after 24 h of 50, 200, or 800 ?g/L of crude ..
  6. Fernández I, Vijayakumar P, Marques C, Cancela M, Gavaia P, Laizé V. Zebrafish vitamin K epoxide reductases: expression in vivo, along extracellular matrix mineralization and under phylloquinone and warfarin in vitro exposure. Fish Physiol Biochem. 2015;41:745-59 pubmed publisher
    ..Expression of vkor genes can represent a reliable indicator to infer VK nutritional status in fish, while ZFB1 cells could represent a suitable in vitro tool to get insights into the mechanisms underlying VK action on fish bone. ..
  7. Lister A, Regan C, Van Zwol J, Van der Kraak G. Inhibition of egg production in zebrafish by fluoxetine and municipal effluents: a mechanistic evaluation. Aquat Toxicol. 2009;95:320-9 pubmed publisher
    ..induced by all treatments of effluent, while EE(2) caused a reduction in the expression levels of CYP1A1, PXR, and CYP3A65...
  8. Jackson J, Kennedy C. Regulation of hepatic abcb4 and cyp3a65 gene expression and multidrug/multixenobiotic resistance (MDR/MXR) functional activity in the model teleost, Danio rerio (zebrafish). Comp Biochem Physiol C Toxicol Pharmacol. 2017;200:34-41 pubmed publisher
    ..In mammals, ligand-mediated pregnane X receptor (PXR) transcriptional activity regulates the induction of P-gp and CYP3A; however, this mechanism has not ..
  9. Blüthgen N, Meili N, Chew G, Odermatt A, Fent K. Accumulation and effects of the UV-filter octocrylene in adult and embryonic zebrafish (Danio rerio). Sci Total Environ. 2014;476-477:207-17 pubmed publisher
    ..Blood levels of 11-ketotestosterone were not altered. The transcriptomics data suggest that OC mainly affects transcription of genes related to developmental processes in the brain and liver as well as metabolic processes in the liver. ..
  10. Zhang Q, Zhang Y, Du J, Zhao M. Environmentally relevant levels of ?-cyhalothrin, fenvalerate, and permethrin cause developmental toxicity and disrupt endocrine system in zebrafish (Danio rerio) embryo. Chemosphere. 2017;185:1173-1180 pubmed publisher
    ..The 3 SPs also caused various alterations to the expression of genes including AhRs, PPAR?, and PXR. These findings suggest that these 3 SPs may cause developmental toxicity to zebrafish larvae by disrupting ..
  11. Chen Q, Jia A, Snyder S, Gong Z, Lam S. Glucocorticoid activity detected by in vivo zebrafish assay and in vitro glucocorticoid receptor bioassay at environmental relevant concentrations. Chemosphere. 2016;144:1162-9 pubmed publisher
    ..The expression of pepck, baiap2 and pxr was up-regulated in zebrafish larvae and the expression of baiap2, pxr and mmp-2 was up-regulated in adult ..
  12. Cheng J, Lv S, Nie S, Liu J, Tong S, Kang N, et al. Chronic perfluorooctane sulfonate (PFOS) exposure induces hepatic steatosis in zebrafish. Aquat Toxicol. 2016;176:45-52 pubmed publisher
  13. Mishra S, Wu S, Fuller A, Wang Z, Rose K, Schey K, et al. Loss of αB-crystallin function in zebrafish reveals critical roles in the development of the lens and stress resistance of the heart. J Biol Chem. 2018;293:740-753 pubmed publisher
  14. Pérez Albaladejo E, Rizzi J, Fernandes D, Lille Langøy R, Karlsen O, Goksøyr A, et al. Assessment of the environmental quality of coastal sediments by using a combination of in vitro bioassays. Mar Pollut Bull. 2016;108:53-61 pubmed publisher
    ..the Po and Danube Rivers was assessed by using a battery of bioassays based on the use of PLHC-1 cells, zebrafish-Pxr-transfected COS-7 cells, and sea bass ovarian subcellular fractions...
  15. Kubota A, Goldstone J, Lemaire B, Takata M, Woodin B, Stegeman J. Role of pregnane X receptor and aryl hydrocarbon receptor in transcriptional regulation of pxr, CYP2, and CYP3 genes in developing zebrafish. Toxicol Sci. 2015;143:398-407 pubmed publisher
    ..Response to a potential agonist for the pregnane X receptor (Pxr) [pregnenolone (PN)] was examined in developing zebrafish, to assess involvement of Pxr in regulation ..
  16. Chang C, Chung H, Su H, Tseng H, Tzou W, Hu C. Regulation of zebrafish CYP3A65 transcription by AHR2. Toxicol Appl Pharmacol. 2013;270:174-84 pubmed publisher
    ..In mammals, CYP3A genes are induced by various xenobiotics through processes mediated by PXR. We previously identified zebrafish CYP3A65 as a CYP3A ortholog that is constitutively expressed in ..