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Tian H, Wang L, Hardy R, Kozhaya L, Placek L, Fleming E, Oh J, Unutmaz D, Yao X. Bioassay-Driven, Fractionation-Empowered, Focused Metabolomics for Discovering Bacterial Activators of Aryl Hydrocarbon Receptor. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2024; 35:518-526. [PMID: 38308645 DOI: 10.1021/jasms.3c00386] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2024]
Abstract
Aryl hydrocarbon receptor (AhR) is a transcription factor that regulates gene expression upon ligand activation, enabling microbiota-dependent induction, training, and function of the host immune system. A spectrum of metabolites, encompassing indole and tryptophan derivatives, have been recognized as activators. This work introduces an integrated, mass spectrometry-centric workflow that employs a bioassay-guided, fractionation-based methodology for the identification of AhR activators derived from human bacterial isolates. By leveraging the workflow efficiency, the complexities inherent in metabolomics profiling are significantly reduced, paving the way for an in-depth and focused mass spectrometry analysis of bioactive fractions isolated from bacterial culture supernatants. Validation of AhR activator candidates used multiple criteria─MS/MS of the synthetic reference compound, bioassay of AhR activity, and elution time confirmation using a C-13 isotopic reference─and was demonstrated for N-formylkynurenine (NFK). The workflow reported provides a roadmap update for improved efficiency of identifying bioactive metabolites using mass spectrometry-based metabolomics. Mass spectrometry datasets are accessible at the National Metabolomics Data Repository (PR001479, Project DOI: 10.21228/M8JM7Q).
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Affiliation(s)
- Huidi Tian
- Department of Chemistry, University of Connecticut, Storrs, Connecticut 06269, United States
| | - Lei Wang
- Department of Chemistry, University of Connecticut, Storrs, Connecticut 06269, United States
| | - Rachel Hardy
- The Jackson Laboratory, 10 Discovery Drive, Farmington, Connecticut 06032, United States
| | - Lina Kozhaya
- The Jackson Laboratory, 10 Discovery Drive, Farmington, Connecticut 06032, United States
| | - Lindsey Placek
- The Jackson Laboratory, 10 Discovery Drive, Farmington, Connecticut 06032, United States
| | - Elizabeth Fleming
- The Jackson Laboratory, 10 Discovery Drive, Farmington, Connecticut 06032, United States
| | - Julia Oh
- The Jackson Laboratory, 10 Discovery Drive, Farmington, Connecticut 06032, United States
| | - Derya Unutmaz
- The Jackson Laboratory, 10 Discovery Drive, Farmington, Connecticut 06032, United States
| | - Xudong Yao
- Department of Chemistry, University of Connecticut, Storrs, Connecticut 06269, United States
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Farooqi AA, Rakhmetova V, Kapanova G, Tanbayeva G, Mussakhanova A, Abdykulova A, Ryskulova AG. Role of Ubiquitination and Epigenetics in the Regulation of AhR Signaling in Carcinogenesis and Metastasis: "Albatross around the Neck" or "Blessing in Disguise". Cells 2023; 12:2382. [PMID: 37830596 PMCID: PMC10571945 DOI: 10.3390/cells12192382] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2023] [Revised: 09/25/2023] [Accepted: 09/27/2023] [Indexed: 10/14/2023] Open
Abstract
The molecular mechanisms and signal transduction cascades evoked by the activation of aryl hydrocarbon receptor (AhR) are becoming increasingly understandable. AhR is a ligand-activated transcriptional factor that integrates environmental, dietary and metabolic cues for the pleiotropic regulation of a wide variety of mechanisms. AhR mediates transcriptional programming in a ligand-specific, context-specific and cell-type-specific manner. Pioneering cutting-edge research works have provided fascinating new insights into the mechanistic role of AhR-driven downstream signaling in a wide variety of cancers. AhR ligands derived from food, environmental contaminants and intestinal microbiota strategically activated AhR signaling and regulated multiple stages of cancer. Although AhR has classically been viewed and characterized as a ligand-regulated transcriptional factor, its role as a ubiquitin ligase is fascinating. Accordingly, recent evidence has paradigmatically shifted our understanding and urged researchers to drill down deep into these novel and clinically valuable facets of AhR biology. Our rapidly increasing realization related to AhR-mediated regulation of the ubiquitination and proteasomal degradation of different proteins has started to scratch the surface of intriguing mechanisms. Furthermore, AhR and epigenome dynamics have shown previously unprecedented complexity during multiple stages of cancer progression. AhR not only transcriptionally regulated epigenetic-associated molecules, but also worked with epigenetic-modifying enzymes during cancer progression. In this review, we have summarized the findings obtained not only from cell-culture studies, but also from animal models. Different clinical trials are currently being conducted using AhR inhibitors and PD-1 inhibitors (Pembrolizumab and nivolumab), which confirm the linchpin role of AhR-related mechanistic details in cancer progression. Therefore, further studies are required to develop a better comprehension of the many-sided and "diametrically opposed" roles of AhR in the regulation of carcinogenesis and metastatic spread of cancer cells to the secondary organs.
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Affiliation(s)
- Ammad Ahmad Farooqi
- Institute of Biomedical and Genetic Engineering (IBGE), Islamabad 54000, Pakistan
| | - Venera Rakhmetova
- Department of Internal Diseases, Medical University of Astana, Astana 010000, Kazakhstan
| | - Gulnara Kapanova
- Faculty of Medicine and healthcare, Al-Farabi Kazakh National University, 71 Al-Farabi Ave, Almaty 050040, Kazakhstan (G.T.)
- Scientific Center of Anti-Infectious Drugs, 75 Al-Farabi Ave, Almaty 050040, Kazakhstan
| | - Gulnur Tanbayeva
- Faculty of Medicine and healthcare, Al-Farabi Kazakh National University, 71 Al-Farabi Ave, Almaty 050040, Kazakhstan (G.T.)
| | - Akmaral Mussakhanova
- Department of Public Health and Management, Astana Medical University, Astana 010000, Kazakhstan;
| | - Akmaral Abdykulova
- Department of General Medical Practice, General Medicine Faculty, Asfendiyarov Kazakh National Medical University, Almaty 050000, Kazakhstan;
| | - Alma-Gul Ryskulova
- Department of Public Health and Social Sciences, Kazakhstan Medical University “KSPH”, Utenos Str. 19A, Almaty 050060, Kazakhstan;
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Meta-Analysis of Transcriptome Data Detected New Potential Players in Response to Dioxin Exposure in Humans. Int J Mol Sci 2020; 21:ijms21217858. [PMID: 33113971 PMCID: PMC7672605 DOI: 10.3390/ijms21217858] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Revised: 10/18/2020] [Accepted: 10/21/2020] [Indexed: 12/26/2022] Open
Abstract
Dioxins are one of the most potent anthropogenic poisons, causing systemic disorders in embryonic development and pathologies in adults. The mechanism of dioxin action requires an aryl hydrocarbon receptor (AhR), but the downstream mechanisms are not yet precisely clear. Here, we performed a meta-analysis of all available transcriptome datasets taken from human cell cultures exposed to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Differentially expressed genes from different experiments overlapped partially, but there were a number of those genes that were systematically affected by TCDD. Some of them have been linked to toxic dioxin effects, but we also identified other attractive targets. Among the genes that were affected by TCDD, there are functionally related gene groups that suggest an interplay between retinoic acid, AhR, and Wnt signaling pathways. Next, we analyzed the upstream regions of differentially expressed genes and identified potential transcription factor (TF) binding sites overrepresented in the genes responding to TCDD. Intriguingly, the dioxin-responsive element (DRE), the binding site of AhR, was not overrepresented as much as other cis-elements were. Bioinformatics analysis of the AhR binding profile unveils potential cooperation of AhR with E2F2, CTCFL, and ZBT14 TFs in the dioxin response. We discuss the potential implication of these predictions for further dioxin studies.
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Sun L, Ye Z, Ling Y, Cai S, Xu J, Fan C, Zhong Y, Shen Q, Li Y. Relationship between polycyclic aromatic hydrocarbons and rheumatoid arthritis in US general population, NHANES 2003-2012. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 704:135294. [PMID: 31791769 DOI: 10.1016/j.scitotenv.2019.135294] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Revised: 10/16/2019] [Accepted: 10/28/2019] [Indexed: 06/10/2023]
Abstract
The purpose of this study was to explore the association between urinary concentrations of polycyclic aromatic hydrocarbon (PAH) metabolites and the prevalence of rheumatoid arthritis (RA). Cross-sectional data were analyzed from the National Health and Nutrition Examination Survey (NHANES) 2003-2012 using levels of nine monohydroxylated urinary PAH metabolites as exposure. Multivariable logistic regression was used to examine the association between urinary biomarkers of PAHs and RA. All of the models were adjusted for age, sex, race, education level, marital status, smoking, BMI, physical activity, energy, diabetes, and survey cycle. Ultimately, 6,072 adults (3,108 men and 2,964 women) 20 years of age or older were analyzed. In the quartile analyses, compared with the lowest quartile, increased RA prevalence was observed in the participants with the highest quartile of 2-hydroxynapthalene (OR = 1.89, 95% CI = 1.28-2.78), 3-hydroxyfluorene (OR = 1.55, 95% CI = 1.07-2.25), 2-hydroxyfluorene (OR = 1.51, 95% CI = 1.02-2.24), 3-hydroxyphenanthrene (OR = 1.50, 95% CI = 1.09-2.07), and 9-hydroxyfluorene (OR = 1.60, 95% CI = 1.10-2.33) in a fully adjusted model, respectively. In the subgroup analysis of current smokers, compared with the participants with lower urinary PAH scores, those with higher scores had a dramatically increased prevalence of RA (OR = 15.46, 95% CI = 3.11-76.75) in the adjusted model. There was a significant interaction between all of the urinary PAH metabolite levels and smoking status in the relationship with RA (P < 0.05). High levels of urinary PAH metabolites are positively associated with RA prevalence in the US general population. PAH exposure and smoking may potentially interact to increase the prevalence of RA. Further prospective studies are needed to clarify the possible effect of PAHs on RA.
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Affiliation(s)
- Lingling Sun
- Department of Orthopaedics, the Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Zhaoming Ye
- Department of Orthopaedics, the Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Yuxiao Ling
- School of Public Health, Hangzhou Medical College, Hangzhou, China
| | - Shaofang Cai
- Department of Science and Education, the Second Affiliated Hospital of Xiamen Medical College, Xiamen, China
| | - Jianling Xu
- Department of Orthopaedics, Pujiang People's Hospital, Jinhua, China
| | - Chunhong Fan
- School of Public Health, Hangzhou Medical College, Hangzhou, China
| | - Yaohong Zhong
- School of Public Health, Hangzhou Medical College, Hangzhou, China
| | - Qing Shen
- School of Public Health, Hangzhou Medical College, Hangzhou, China
| | - Yingjun Li
- School of Public Health, Hangzhou Medical College, Hangzhou, China.
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Bian Y, Li Y, Shrestha G, Wen X, Cai B, Wang K, Wan X. ITE, an endogenous aryl hydrocarbon receptor ligand, suppresses endometrial cancer cell proliferation and migration. Toxicology 2019; 421:1-8. [PMID: 30953668 DOI: 10.1016/j.tox.2019.03.017] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2018] [Revised: 02/16/2019] [Accepted: 03/29/2019] [Indexed: 01/16/2023]
Abstract
BACKGROUND Identification of new molecular targets for the treatment of endometrial cancer (EC) is an important clinical goal, especially for the patients which were resistant to conventional therapies. The aryl hydrocarbon receptor (AhR) is a ligand- activated transcription factor known primarily as the mediator of dioxin toxicity. However, the AhR can also inhibit cellular proliferation in a ligand-dependent manner and act as a tumor suppressor in mice, thus may be a potential anticancer target. In this study, we investigated if the endogenous AhR ligand 2-(1'H-indole-3'-carbonyl)-thiazole-4-carboxylic acid methyl ester (ITE) regulated proliferation and migration of EC cells via AhR. METHODS We used quantitative real-time PCR and western blot to assess the expression of AhR in EC tissues and paired adjacent normal tissues. In addition, we conducted transwell assay to test whether the treatment of ITE altered the locomotive potential and proliferation of EC cells. Next, we conducted mouse xenograft models to further explore the in vivo effect of ITE. RESULTS We found that the AhR protein and RNA levels were increased mildly in EC tissues relative to the para-tumor normal endometrial tissues. Besides, ITE suppressed EC cells proliferation and migration in vitro, and also suppressed EC cells xenograft growth in mice. CONCLUSIONS Our results strongly supported the possibility of using the ITE as a small molecular compound for the treatment of EC.
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Affiliation(s)
- Yiding Bian
- Clinical and Translational Research Center, Shanghai First Maternity and Infant Hospital, Tongji University School of Medicine, Shanghai, PR China
| | - Yiran Li
- Department of Gynecology, Shanghai First Maternity and Infant Hospital, Tongji University School of Medicine, Shanghai, PR China
| | - Garima Shrestha
- Clinical and Translational Research Center, Shanghai First Maternity and Infant Hospital, Tongji University School of Medicine, Shanghai, PR China
| | - Xiaoli Wen
- Clinical and Translational Research Center, Shanghai First Maternity and Infant Hospital, Tongji University School of Medicine, Shanghai, PR China
| | - Bailian Cai
- Clinical and Translational Research Center, Shanghai First Maternity and Infant Hospital, Tongji University School of Medicine, Shanghai, PR China
| | - Kai Wang
- Clinical and Translational Research Center, Shanghai First Maternity and Infant Hospital, Tongji University School of Medicine, Shanghai, PR China.
| | - Xiaoping Wan
- Department of Gynecology, Shanghai First Maternity and Infant Hospital, Tongji University School of Medicine, Shanghai, PR China.
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Sharma RP, Schuhmacher M, Kumar V. Review on crosstalk and common mechanisms of endocrine disruptors: Scaffolding to improve PBPK/PD model of EDC mixture. ENVIRONMENT INTERNATIONAL 2017; 99:1-14. [PMID: 27697394 DOI: 10.1016/j.envint.2016.09.016] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Revised: 09/18/2016] [Accepted: 09/19/2016] [Indexed: 06/06/2023]
Abstract
Endocrine disruptor compounds (EDCs) are environment chemicals that cause harmful effects through multiple mechanisms, interfering with hormone system resulting in alteration of homeostasis, reproduction and developmental effect. Many of these EDCs have concurrent exposure with crosstalk and common mechanisms which may lead to dynamic interactions. To carry out risk assessment of EDCs' mixture, it is important to know the detailed toxic pathway, crosstalk of receptor and other factors like critical window of exposure. In this review, we summarize the major mechanism of actions of EDCs with the different/same target organs interfering with the same/different class of hormone by altering their synthesis, metabolism, binding and cellular action. To show the impact of EDCs on life stage development, a case study on female fertility affecting germ cell is illustrated. Based on this summarized discussion, major groups of EDCs are classified based on their target organ, mode of action and potential risk. Finally, a conceptual model of pharmacodynamic interaction is proposed to integrate the crosstalk and common mechanisms that modulate estrogen into the predictive mixture dosimetry model with dynamic interaction of mixture. This review will provide new insight for EDCs' risk assessment and can be used to develop next generation PBPK/PD models for EDCs' mixture analysis.
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Affiliation(s)
- Raju Prasad Sharma
- Center of Environmental Food and Toxicological Technology (TecnATox), Departament d'Enginyeria Química, Universitat Rovira i Virgili, Tarragona, Catalonia, Spain
| | - Marta Schuhmacher
- Center of Environmental Food and Toxicological Technology (TecnATox), Departament d'Enginyeria Química, Universitat Rovira i Virgili, Tarragona, Catalonia, Spain
| | - Vikas Kumar
- Center of Environmental Food and Toxicological Technology (TecnATox), Departament d'Enginyeria Química, Universitat Rovira i Virgili, Tarragona, Catalonia, Spain.
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7
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Wang L, Liang XF, Zhang WB, Mai KS, Huang Y, Shen D. Amnesic shellfish poisoning toxin stimulates the transcription of CYP1A possibly through AHR and ARNT in the liver of red sea bream Pagrus major. MARINE POLLUTION BULLETIN 2009; 58:1643-1648. [PMID: 19665739 DOI: 10.1016/j.marpolbul.2009.07.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2009] [Revised: 07/02/2009] [Accepted: 07/03/2009] [Indexed: 05/28/2023]
Abstract
To investigate the role of detoxification-related liver genes in amnesic shellfish poisoning toxin metabolism, red sea bream Pagrus major were exposed to domoic acid (DA, 2mugg(-1) wet weight) for 24h. Hepatic mRNA expression levels of AHR, ARNT, CYP1 and GSTs were determined by semi-quantitative RT-PCR. The cytosolic factors aryl hydrocarbon receptor (AHR) and aryl hydrocarbon receptor nuclear translocator (ARNT) mRNA levels of DA exposure group were substantially enhanced by 113.3% and 90.9%, respectively. Consistent with this result, the phase I xenobiotic metabolizing enzyme (XME) cytochrome P-450 1A (CYP1A) was significantly induced. In contrast, the transcriptions of three major phase II XME glutathione S-transferases as well as heat shock protein 70 were not significantly affected by DA exposure. These results suggest a possible role of CYP1A after DA exposure in the toxin metabolism of marine fish, possibly through the AHR/ARNT signaling pathway.
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Affiliation(s)
- Lin Wang
- College of Life Science and Technology, Jinan University, Guangzhou 510632, China
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Tian Y. Ah receptor and NF-kappaB interplay on the stage of epigenome. Biochem Pharmacol 2008; 77:670-80. [PMID: 19014911 DOI: 10.1016/j.bcp.2008.10.023] [Citation(s) in RCA: 110] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2008] [Revised: 10/16/2008] [Accepted: 10/21/2008] [Indexed: 12/15/2022]
Abstract
The aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor that belongs to the basic helix-loop-helix/Per-ARNT-Sim (bHLH-PAS) family. Its ligands include many natural and synthetic compounds, some of which, such as polyhalogenated aromatic hydrocarbons and polycyclic aromatic hydrocarbons, are important environmental contaminants. NF-kappaB is a pleiotropic factor that regulates many physiological and pathophysiological processes including the immune and inflammatory responses. In the past decade, accumulating evidence suggests close interactions between AhR and NF-kappaB pathways, and these interactions are potentially important mechanisms for many pathological processes such as the chemical-induced immune dysfunctions, carcinogenesis and alteration of xenobiotic metabolism and disposition. AhR-NF-kappaB interaction has become a mechanistic linchpin linking certain pathological responses induced by environmental insults. Furthermore, the AhR-NF-kappaB interaction provides basis for therapeutic applications of certain AhR ligands to treat human diseases. The effects of AhR-NF-kappaB on the epigenome are an important area that is not well understood. In this review, I highlight current research regarding the AhR-NF-kappaB(RelA) interactions with emphasis on the epigenetic impacts of these interactions on chromatin modifications and transcription elongation control.
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Affiliation(s)
- Yanan Tian
- Interdisciplinary Graduate Program of Toxicology, Department of Veterinary Physiology and Pharmacology, Texas A&M University, College Station, TX 77843-4466, USA.
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Cheshenko K, Pakdel F, Segner H, Kah O, Eggen RIL. Interference of endocrine disrupting chemicals with aromatase CYP19 expression or activity, and consequences for reproduction of teleost fish. Gen Comp Endocrinol 2008; 155:31-62. [PMID: 17459383 DOI: 10.1016/j.ygcen.2007.03.005] [Citation(s) in RCA: 221] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2006] [Revised: 03/05/2007] [Accepted: 03/09/2007] [Indexed: 11/28/2022]
Abstract
Many natural and synthetic compounds present in the environment exert a number of adverse effects on the exposed organisms, leading to endocrine disruption, for which they were termed endocrine disrupting chemicals (EDCs). A decrease in reproduction success is one of the most well-documented signs of endocrine disruption in fish. Estrogens are steroid hormones involved in the control of important reproduction-related processes, including sexual differentiation, maturation and a variety of others. Careful spatial and temporal balance of estrogens in the body is crucial for proper functioning. At the final step of estrogen biosynthesis, cytochrome P450 aromatase, encoded by the cyp19 gene, converts androgens into estrogens. Modulation of aromatase CYP19 expression and function can dramatically alter the rate of estrogen production, disturbing the local and systemic levels of estrogens. In the present review, the current progress in CYP19 characterization in teleost fish is summarized and the potential of several classes of EDCs to interfere with CYP19 expression and activity is discussed. Two cyp19 genes are present in most teleosts, cyp19a and cyp19b, primarily expressed in the ovary and brain, respectively. Both aromatase CYP19 isoforms are involved in the sexual differentiation and regulation of the reproductive cycle and male reproductive behavior in diverse teleost species. Alteration of aromatase CYP19 expression and/or activity, be it upregulation or downregulation, may lead to diverse disturbances of the above mentioned processes. Prediction of multiple transcriptional regulatory elements in the promoters of teleost cyp19 genes suggests the possibility for several EDC classes to affect cyp19 expression on the transcriptional level. These sites include cAMP responsive elements, a steroidogenic factor 1/adrenal 4 binding protein site, an estrogen-responsive element (ERE), half-EREs, dioxin-responsive elements, and elements related to diverse other nuclear receptors (peroxisome proliferator activated receptor, retinoid X receptor, retinoic acid receptor). Certain compounds including phytoestrogens, xenoestrogens, fungicides and organotins may modulate aromatase CYP19 activity on the post-transcriptional level. As is shown in this review, diverse EDCs may affect the expression and/or activity of aromatase cyp19 genes through a variety of mechanisms, many of which need further characterization in order to improve the prediction of risks posed by a contaminated environment to teleost fish population.
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Affiliation(s)
- Ksenia Cheshenko
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Ueberlandstrasse 133, Postfach 611, CH 8600 Dübendorf, Switzerland
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Yang S, Tian F, Li Z. Molecular graph fingerprint: a new molecular structural characterization method for the modelling and prediction of chromatographic retention behaviour of several persistent organic pollutants. SAR AND QSAR IN ENVIRONMENTAL RESEARCH 2008; 19:541-553. [PMID: 18853301 DOI: 10.1080/10629360802083822] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
How to extract and characterize information on molecular microstructures is deemed to be the key task to accurately simulate and predict molecular properties. In terms of atomic attributes, atoms in a molecule are divided into three levels. Based upon that, inter-atomic correlations are mapped to certain reasonable spatial coordinates in virtue of radial distribution function, generating the novel molecular graph fingerprint (MoGF), which essentially provides insight into molecular inner structures. MoGF, committing itself to transformation of molecular structures into characteristic graph curves, shows valuable advantages such as easy calculation, experimental parameters-free, rich information content, and structural significance and intuitive expressions. QSRR studies were performed for 115 polychlorinated dibenzofurans (PCDFs), 41 polychlorinated dibenzo-p-dioxins (PCDDs), 62 polychlorinated naphthalenes (PCNs), and 210 polychlorinated biphenyls (PCBs including the biphenyl)) tested for their retention behaviours on gas chromatographic column DB-5. The resulting PLS models showed good performances with correlation coefficients for both training and test sets above 0.97.
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Affiliation(s)
- S Yang
- College of Bioengineering, Chongqing University, Chongqing, China
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11
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Mandal PK. Dioxin: a review of its environmental effects and its aryl hydrocarbon receptor biology. J Comp Physiol B 2005; 175:221-30. [PMID: 15900503 DOI: 10.1007/s00360-005-0483-3] [Citation(s) in RCA: 374] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2004] [Revised: 01/27/2005] [Accepted: 03/08/2005] [Indexed: 12/20/2022]
Abstract
A highly persistent trace environmental contaminant and one of the most potent toxicants known is dioxin (2,3,7,8-tetrachlorodibenzo-para-dioxin or TCDD). TCDD induces a broad spectrum of biological responses, including induction of cytochrome P-450 1A1 (CYP1A1), disruption of normal hormone signaling pathways, reproductive and developmental defects, immunotoxicity, liver damage, wasting syndrome, and cancer. Its classification was upgraded from "possible human carcinogen" (group 2B) to "human carcinogen" (group 1) by the International Agency for Research on Cancer (IARC) in 1997. Exposure to TCDD may also cause changes in sex ratio, and tumor promotion in other animals. Because of the growing public and scientific concern, toxicological studies have been initiated to analyze the short- and long-term effects of dioxin. TCDD brings about a wide variety of toxic and biochemical effects via aryl hydrocarbon receptor (AhR)-mediated signaling pathways. Essential steps in this adaptive mechanism include AhR binding of ligand in the cytoplasm of cells associated with two molecules of chaperone heatshock protein (Hsp90) and AhR interactive protein, translocation of the receptor to the nucleus, dimerization with the Ah receptor nuclear translocator, and binding of this heterodimeric transcription factor (present in CYP1A) to dioxin-responsive elements upstream of promoters that regulate the expression of genes involved in xenobiotic metabolism.
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Affiliation(s)
- Prabir K Mandal
- Department of Biology, University of North Florida, 4567 St. John's Bluff Road (South), Jacksonville, FL, 32224, USA.
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12
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Matsumura F. On the significance of the role of cellular stress response reactions in the toxic actions of dioxin. Biochem Pharmacol 2003; 66:527-40. [PMID: 12906918 DOI: 10.1016/s0006-2952(03)00157-6] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Dioxin is known to cause many toxic effects that vary greatly in different tissues, ages, genders, and species. In this review, an attempt has been made to sort out major signaling pathways involved in the expression of the toxicities of dioxin. The major strategy adopted in analyzing its major signaling pathways is to view the toxic actions of dioxin as the result of the Ah receptor-mediated expression of a major cellular emergency stress response signal. Evidence pointing to the similarities between the symptoms of poisoning by dioxin and those produced by chronic administration of typical stressors, particularly lipopolysaccharides (LPS), bacterial endotoxins, has been assembled and analyzed. The common symptoms are wasting syndrome, atherosclerosis, fatty liver, and thymic atrophy. On the other hand, oxidative stress caused by cytochrome P450 induction is one of the typical stresses of dioxin poisoning, but not LPS poisoning. One of the major means through which dioxin triggers stress responses via "stress-activated kinase pathways" is stimulation of the cellular production of cytokines/autocrines, particularly growth factors. In the case of hepatocytes for instance, transforming growth factor-alpha plays a pivotal role in the dioxin-induced activation of the epidermal growth factor receptor and the extracellular signal-related kinase pathway, which acts as a signal to suppress apoptosis induced by cellular stress. These observations as well as additional experimental data support the idea that one of the major functions of the Ah receptor could be the elicitation of cellular stress response reactions. Another key point in understanding the toxic action of dioxin is that, unlike other cases of stressors, dioxin signaling becomes chronically sustained because of its extreme persistence in the human body, its half-life of 7-10 years, and its selective accumulation in fatty target tissues.
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Affiliation(s)
- Fumio Matsumura
- Department of Environmental Toxicology, University of California, One Shields Avenue, Davis, CA, USA.
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Pelkonen O, Hukkanen J, Honkakoski P, Hakkola J, Viitala P, Raunio H. In vitro screening of cytochrome P450 induction potential. ERNST SCHERING RESEARCH FOUNDATION WORKSHOP 2002:105-37. [PMID: 11975192 DOI: 10.1007/978-3-662-04383-7_6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- O Pelkonen
- Department of Pharmacology and Toxicology, University of Oulu, 90014 Oulu, Finland.
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14
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Pearl LH, Prodromou C. Structure, function, and mechanism of the Hsp90 molecular chaperone. ADVANCES IN PROTEIN CHEMISTRY 2002; 59:157-86. [PMID: 11868271 DOI: 10.1016/s0065-3233(01)59005-1] [Citation(s) in RCA: 160] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- L H Pearl
- Section of Structural Biology, Institute of Cancer Research, Chester Beatty Laboratories, 237 Fulham Road, London SW3 6JB, UK
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15
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Pratt WB, Silverstein AM, Galigniana MD. A model for the cytoplasmic trafficking of signalling proteins involving the hsp90-binding immunophilins and p50cdc37. Cell Signal 1999; 11:839-51. [PMID: 10659992 DOI: 10.1016/s0898-6568(99)00064-9] [Citation(s) in RCA: 123] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
A number of transcription factors and protein kinases involved in signal transduction exist in heterocomplexes with the ubiquitous and essential protein chaperone hsp90. These signalling protein x hsp90 heterocomplexes are assembled by a multiprotein chaperone system comprising hsp90, hsp70, Hop, hsp40, and p23. In the case of transcription factors, the heterocomplexes with hsp90 also contain a high molecular weight immunophilin with tetratricopeptide repeat (TPR) motifs, such as FKBP52 or CyP-40. In the case of the protein kinases, the heterocomplexes contain p50cdc37. The immunophilins bind to a single TPR acceptor site on hsp90, and p50cdc37 binds to an adjacent site so that binding is exclusive for p50cdc37 or an immunophilin. Direct interaction of immunophilins with the transcription factors or p50cdc37 with the protein kinases leads to selection of different heterocomplexes after their assembly by a common mechanism. Studies with the glucocorticoid receptor, for which translocation from the cytoplasm to the nucleus is under hormonal control, suggest that dynamic assembly of the heterocomplexes is required for rapid movement of the receptor through the cytoplasm along cytoskeletal tracts. As for the similar short-range trafficking of vesicles along microtubules, there must be a mechanism for linking the signalling protein solutes to the molecular motors involved in movement. We present here a model in which the immunophilins and p50cdc37 target, respectively, the retrograde or anterograde direction of signalling protein movement by functioning as connectors that link the signalling proteins to the movement machinery.
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Affiliation(s)
- W B Pratt
- Department of Pharmacology, University of Michigan Medical School, Ann Arbor 48109, USA
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16
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Hahn ME. The aryl hydrocarbon receptor: a comparative perspective. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY. PART C, PHARMACOLOGY, TOXICOLOGY & ENDOCRINOLOGY 1998; 121:23-53. [PMID: 9972449 DOI: 10.1016/s0742-8413(98)10028-2] [Citation(s) in RCA: 114] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The aryl hydrocarbon receptor (Ah receptor or AHR) is a ligand-activated transcription factor involved in the regulation of several genes, including those for xenobiotic-metabolizing enzymes such as cytochrome P450 1A and 1B forms. Ligands for the AHR include a variety of aromatic hydrocarbons, including the chlorinated dioxins and related halogenated aromatic hydrocarbons whose toxicity occurs through activation of the AHR. The AHR and its dimerization partner ARNT are members of the emerging bHLH-PAS family of transcriptional regulatory proteins. In this review, our current understanding of the AHR signal transduction pathway in non-mammalian and other non-traditional species is summarized, with an emphasis on similarities and differences in comparison to the AHR pathway in rodents and humans. Evidence and prospects for the presence of a functional AHR in early vertebrates and invertebrates are also examined. An overview of the bHLH-PAS family is presented in relation to the diversity of bHLH-PAS proteins and the functional and evolutionary relationships of the AHR and ARNT to the other members of this family. Finally, some of the most promising directions for future research on the comparative biochemistry and molecular biology of the AHR and ARNT are discussed.
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Affiliation(s)
- M E Hahn
- Biology Department, Woods Hole Oceanographic Institution, MA 02543-1049, USA.
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17
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Lindros KO, Oinonen T, Kettunen E, Sippel H, Muro-Lupori C, Koivusalo M. Aryl hydrocarbon receptor-associated genes in rat liver: regional coinduction of aldehyde dehydrogenase 3 and glutathione transferase Ya. Biochem Pharmacol 1998; 55:413-21. [PMID: 9514075 DOI: 10.1016/s0006-2952(97)00495-4] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The tumor-associated aldehyde dehydrogenase 3 (ALDH3) and the glutathione transferase (GST)Ya form are coded by members of the Ah (aryl hydrocarbon) battery group of genes activated in the liver by polycyclic hydrocarbons such as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). The physiological role of the Ah receptor (AHR), its gene-activating mechanism and its endogenous ligands are still poorly clarified. We had previously observed that 3-methylcholanthrene (3MC) and beta-naphthoflavone (betaNF) induced the AHR-associated CYP1A1/1A2 pair in different liver regions, an effect not explained by the acinar distribution of the AHR protein. Here, we investigated AHR-associated regional induction by comparing the expression patterns of ALDH3 and GSTYa. Analysis of samples from periportal and perivenous cell lysates from 3MC-treated animals revealed that ALDH3 mRNA, protein and benzaldehyde-NADP associated activity were all confined to the perivenous region. In contrast, such regio-specific induction was not seen after beta-NF induction. Immunohistochemically, a peculiar mono- or oligocellular induction pattern of ALDH3 was seen, consistently surrounding terminal hepatic veins after 3MC but mainly in the midzonal region after betaNF. A ligand-specific difference in regional induction of GSTYa1 mRNA was also observed: The constitutive perivenous dominance was preserved after 3MC while induction by betaNF was mainly periportal. A 3MC-betaNF difference was also seen by immunohistochemistry and at the GSTYa protein level, in contrast to that of the AHR-unassociated GSTYb protein. However, experiments with hepatocytes isolated from the periportal or perivenous region to replicate these inducer-specific induction responses in vitro were unsuccessful. These data demonstrate that the different acinar induction patterns by 3MC and betaNF previously observed for CYP1A1 and CYP1A2 are seen also for two other Ah battery genes, GSTYa1 and ALDH3, but in a modified, gene-specific form. We hypothesize that unknown protein(s) operating in vivo and modifying the Ah-mediated response at the common XRE element located upstream of these genes is affected zonespecifically by 3MC and betaNF.
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Affiliation(s)
- K O Lindros
- National Public Health Institute, Alcohol Research Center, Helsinki, Finland.
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18
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Csaba G, Inczefi-Gonda A. Effect of combined neonatal imprinting by vitamin A, vitamin D3, benzpyrene and allylestrenol on adult rat thymus glucocorticoid and uterine estrogen receptors. GENERAL PHARMACOLOGY 1997; 29:779-81. [PMID: 9347325 DOI: 10.1016/s0306-3623(97)00019-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
1. Combined neonatal imprinting with allylestrenol, vitamins A and D3 and benzpyrene significantly increased thymic glucocorticoid receptor capacity in male and female animals and decreased receptors affinity in adult females only. 2. Uterine estrogen receptor affinity or density was not influenced. 3. Considering that perinatal treatment with allylestrenol or vitamin D3 decreased glucocorticoid receptor capacity, the dominance of the positive effect of retinol should be surmised. 4. The experiments call attention to the interrelation of different materials acting simultaneously in the perinatal period.
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Affiliation(s)
- G Csaba
- Department of Biology, Semmelweis University of Medicine, Budapest, Hungary
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19
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Abstract
We have provided a historical perspective on a body of steroid receptor research dealing with the structure and physiological significance of the untransformed 9S receptor that has often confused both novice and expert investigators. The frequent controversies and equivocations of earlier studies were due to the fact that the native, hormone-free state of these receptors is a large multiprotein complex that resisted description for many years because of its unstable and dynamic nature. The untransformed 9S state of the steroid and dioxin receptors has provided a unique system for studying the function of the ubiquitous, abundant, and conserved heat shock protein, hsp90. The hormonal control of receptor association with hsp90 provided a method of manipulating the receptor heterocomplex in a manner that was physiologically meaningful. For several steroid receptors, binding to hsp90 was required for the receptor to be in a native hormone-binding state, and for all of the receptors, hormone binding promoted dissociation of the receptor from hsp90 and conversion of the receptor to the DNA-binding state. Although the complexes between tyrosine kinases and hsp90 were discovered earlier, the hormonal regulation or steroid receptor association with hsp90 permitted much more rapid and facile study of hsp90 function. The observations that hsp90 binds to the receptors through their HBDs and that these domains can be fused to structurally different proteins bringing their function under hormonal control provided a powerful linkage between the hormonal regulation of receptor binding to hsp90 and the initial step in steroid hormone action. Because the 9S receptor hsp90 heterocomplexes could be physically stabilized by molybdate, their protein composition could be readily studied, and it became clear that these complexes are multiprotein structures containing a number of unique proteins, such as FKBP51, FKBP52, CyP-40, and p23, that were discovered because of their presence in these structures. Further analysis showed that hsp90 itself exists in a variety of native multiprotein heterocomplexes independent of steroid receptors and other 'substrate' proteins. Cell-free systems can now be used to study the formation of receptor heterocomplexes. As we outlined in the scheme of Fig. 1, the multicomponent receptor-hsp90 heterocomplex assembly system is being reconstituted, and the importance of individual proteins, such as hsp70, p60, and p23, in the assembly process is becoming recognized. It should be noted that our understanding of the mechanism and purpose of steroid receptor heterocomplex assembly is still at an early stage. We can now speculate on the roles of receptor-associated proteins in receptor action, both as individuals and as a group, but their actual functions are still vague or unknown. We can make realistic models about the chaperoning and trafficking of steroid receptors, but we don't yet know how these processes occur, we don't know where chaperoning occurs in the cell (e.g. Is it limited to the cytoplasm? Is it a diffuse process or does chaperoning occur in association with structural elements?), and, with the exception of the requirement for hormone binding, we don't know the extent to which the hsp90-based chaperone system impacts on steroid hormone action. It is not yet clear how far the discovery of this hsp90 heterocomplex assembly system will be extended to the development of a general understanding of protein processing in the cell. Because this assembly system is apparently present in all eukaryotic cells, it probably performs an essential function for many proteins. The bacterial homolog of hsp90 is not an essential protein, but hsp90 is essential in eukaryotes, and recent studies indicate that the development of the cell nucleus from prokaryotic progenitors was accompanied by the duplication of genes for hsp90 and hsp70 (698). (ABSTRACT TRUNCATED)
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Affiliation(s)
- W B Pratt
- Department of Pharmacology, University of Michigan Medical School, Ann Arbor 48109, USA
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20
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Pratt WB. The role of the hsp90-based chaperone system in signal transduction by nuclear receptors and receptors signaling via MAP kinase. Annu Rev Pharmacol Toxicol 1997; 37:297-326. [PMID: 9131255 DOI: 10.1146/annurev.pharmtox.37.1.297] [Citation(s) in RCA: 242] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The multicomponent heat-shock protein (hsp) 90-based chaperone system is an ubiquitous protein-folding system in the cytoplasm of eukaryotes. Several signal transduction systems utilize an interaction with hsp90 as an essential component of the signaling pathway. The steroid and dioxin receptors are bound to hsp90 through their hormone-binding domains, and several of them must be bound to hsp90 in order to have a ligand-binding site. The binding of ligands to these receptors promotes their dissociation from hsp90, an event that is the first step in their signaling pathways. Several protein kinases, including the Src and Raf components of the MAP kinase system, are also bound to hsp90. Genetic studies in yeast have demonstrated that hsp90 is required for normal signaling via steroid and dioxin receptors and for the activity of Src in vivo. The hsp90-based chaperone system has been reconstituted from purified components, permitting detailed analysis of the molecular basis of the chaperone's role in signal transduction.
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Affiliation(s)
- W B Pratt
- Department of Pharmacology, University of Michigan, Ann Arbor 48109, USA
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21
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Abstract
2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) and related compounds bind to the intracellular aryl hydrocarbon (Ah) receptor and induce a diverse spectrum of biochemical and toxic responses. Ah receptor agonists also modulate several endocrine pathways, and research in several laboratories has shown that TCDD and related compounds inhibit estrogen (E2)-induced responses in the rodent mammary and uterus and in human breast cancer cell lines. The mechanisms of interaction between the TCDD- and E2-induced signaling pathways are complex and some of the inhibitory effects may be related to 5'-flanking inhibitory-dioxin responsive elements (i-DREs) in target genes. The antiestrogenic and antitumorigenic activity of Ah receptor agonists has been used to prepare a series of relatively non-toxic alkyl polychlorinated dibenzofurans which have clinical potential for treatment of mammary cancer.
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Affiliation(s)
- S Safe
- Texas A&M University, College Station 77843-4466, USA
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22
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Coumailleau P, Poellinger L, Gustafsson JA, Whitelaw ML. Definition of a minimal domain of the dioxin receptor that is associated with Hsp90 and maintains wild type ligand binding affinity and specificity. J Biol Chem 1995; 270:25291-300. [PMID: 7559670 DOI: 10.1074/jbc.270.42.25291] [Citation(s) in RCA: 116] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
The dioxin receptor is a cytoplasmic basic helix-loop-helix/Per-Arnt-Sim homology (bHLH/PAS) protein known to bind planar polycyclic ligands including polycyclic aromatic hydrocarbons, benzoflavones, heterocyclic amines, and halogenated aromatic hydrocarbons, e.g. dioxins. Ligand-induced activation of the dioxin receptor initiates a process whereby the receptor is transformed into a nuclear transcription factor complex with a specific bHLH/PAS partner protein, Arnt. In analogy to the glucocorticoid receptor, the latent dioxin receptor is found associated with the molecular chaperone hsp90. We have defined and isolated a minimal ligand binding domain of the dioxin receptor from the central PAS region, comprising of amino acids 230 to 421, and found this domain to interact with hsp90 in vitro. Expression of the minimal ligand binding domain in wheat germ lysates or bacteria, systems which harbor hsp90 homologs unable to interact with the glucocorticoid or dioxin receptors, resulted in non-ligand binding forms of this minimal 230 to 421 fragment. Importantly, affinity of the minimal ligand binding domain for dioxin was similar to the affinity inherent in the full-length dioxin receptor, and a profile of ligand structures which specifically bound the minimal ligand binding domain was found to be conserved between this domain and the native receptor. These experiments show that the minimal ligand binding domain maintains the quantitative and qualitative aspects of ligand binding exhibited by the full-length receptor, implying that the central ligand binding pocket may exist to accommodate all classes of specific dioxin receptor ligands, and that this pocket is critically dependent upon hsp90 for its ligand binding conformation.
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Affiliation(s)
- P Coumailleau
- Department of Medical Nutrition, Karolinska Institute, Huddinge University Hospital F-60, Sweden
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23
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Antonsson C, Arulampalam V, Whitelaw ML, Pettersson S, Poellinger L. Constitutive function of the basic helix-loop-helix/PAS factor Arnt. Regulation of target promoters via the E box motif. J Biol Chem 1995; 270:13968-72. [PMID: 7775458 DOI: 10.1074/jbc.270.23.13968] [Citation(s) in RCA: 71] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Arnt is a nuclear basic helix-loop-helix (bHLH) transcription factor that, contiguous with the bHLH motif, contains a region of homology (PAS) with the Drosophila factors Per and Sim. Arnt dimerizes in a ligand-dependent manner with the bHLH dioxin receptor, a process that enables the dioxin-(2,3,7,8-tetrachlorodibenzo-p-dioxin)-activated Arnt-dioxin receptor complex to recognize dioxin response elements of target promoters. In the absence of dioxin, Arnt does not bind to this target sequence motif. The constitutive function of Arnt is presently not understood. Here we demonstrate that Arnt constitutively bound the E box motif CACGTG that is also recognized by a number of distinct bHLH factors, including USF and Max. Importantly, amino acids that have been identified to be critical for E box recognition by Max and USF are conserved in Arnt. Consistent with these observations, full-length Arnt, but not an Arnt deletion mutant lacking its potent C-terminal transactivation domain, constitutively activated CACGTG E box-driven reporter genes in vivo. These results indicate a role of Arnt in regulation of a network of target genes that is distinct from that regulated by the Arnt-dioxin receptor complex in dioxin-stimulated cells.
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Affiliation(s)
- C Antonsson
- Department of Medical Nutrition, Karolinska Institute, Novum, Huddinge, Sweden
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