The aryl hydrocarbon receptor (AhR) mediates biological and toxicological actions of e.g., halogenated aromatic hydrocarbons such as 2,3,7,8-tetrachlorodibenzo-p-dioxin. Although much is known about the biochemical and molecular mechanisms of AhR action, little is known about the control of the expression of the AhR gene itself. Therefore, we aimed at the identification and characterization of regions important for constitutive AhR gene expression. First, we screened 2.6 kb of the 5(')-flanking region of the AhR gene in 91 healthy Caucasian volunteers for naturally occurring genetic variants. Seven variants were detected. However, they do not seem to influence AhR gene expression in lymphocytes. Using a 2.7 kb AhR promoter luciferase reporter gene construct and various deletion constructs, a putative regulatory region was identified and characterized further by electrophoretic mobility shift assays and site-directed mutagenesis. These investigations were confirmed by cotransfection experiments in Drosophila SL2 cells. The obtained results prove an involvement of Sp1 in AhR gene regulation.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.abb.2003.10.005 | DOI Listing |
Ecotoxicol Environ Saf
January 2025
Department of Stomatology, the Affiliated Suzhou Hospital of Nanjing Medical University, Suzhou Municipal Hospital, Gusu School, Nanjing Medical University, No. 242, Guangji Road, Suzhou, Jiangsu Province 215000, China. Electronic address:
Exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in utero can result in osteogenic defect during palatogenesis, but the effects on other craniofacial bones and underlying mechanisms remain to be characterized. By treating pregnant mice with TCDD (40 μg/kg) at the vital craniofacial patterning stages (embryonic day 8.5, 10.
View Article and Find Full Text PDFRespirology
January 2025
School of Health and Biomedical Sciences, RMIT University, Melbourne, Victoria, Australia.
Background And Objective: Asthma-COPD overlap (ACO) is characterized by patients exhibiting features of both asthma and COPD. Currently, there is no specific treatment for ACO. This study aimed to investigate the therapeutic potential of targeting CD131, a shared receptor subunit for IL-3, IL-5 and GM-CSF, in ACO development and in preventing acute viral exacerbations.
View Article and Find Full Text PDFCurr Neuropharmacol
January 2025
Department of Stem Cell Bioengineering, Mossakowski Medical Research Institute, Polish Academy of Sciences, Pawinskiego 5 Str, 02-106 Warsaw, Poland.
The purpose of this review was to analyse the literature regarding the correlation between the level of tryptamine, aryl hydrocarbon receptor (AHR) signalling pathway activation, and monoamine oxidase (MAO)-A and MAO-B activity in health and conditions such as neurodegenerative, neurodevelopmental, and psychiatric disorders. Tryptamine is generated through the decarboxylation of tryptophan by aromatic amino acid decarboxylase (AADC) in the central nervous system (CNS), peripheral nervous system (PNS), endocrine system, and gut bacteria. Organ-specific metabolism of tryptamine, which is mediated by different MAO isoforms, causes this trace amine to have different pharmacokinetics between the brain and periphery.
View Article and Find Full Text PDFCells
January 2025
Research Institute of Medical and Health Sciences, University of Sharjah, Sharjah P.O. Box 27272, United Arab Emirates.
The Kynurenine pathway is crucial in metabolizing dietary tryptophan into bioactive compounds known as kynurenines, which have been linked to glucose homeostasis. The aryl hydrocarbon receptor (AhR) has recently emerged as the endogenous receptor for the kynurenine metabolite, kynurenic acid (KYNA). However, the specific role of AhR in pancreatic β-cells remains largely unexplored.
View Article and Find Full Text PDFESMO Open
January 2025
Division of Molecular Oncology & Immunology, Netherlands Cancer Institute, Amsterdam, The Netherlands; Oncode Institute, Utrecht, The Netherlands. Electronic address:
Background: Many patients with cancer exhibit primary or rapid secondary resistance to targeted therapy (TT). We hypothesized that a higher number of altered oncogenic signaling pathways [pathway alteration load (PAL)] would reduce the benefit of TT which only intervenes in one pathway. This hypothesis was tested in the Drug Rediscovery Protocol (DRUP).
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!