The firstly discovered AhR function is its role in xenobiotic metabolism via the genomic pathway.
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Endogenous functions are described, involving alternative pathways such as the non-genomic pathway.
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A strong involvement in cell physiology (proliferation, adhesion and migration) was related.
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AhR also have physiological roles identified by KO-models, the most common of which is vascular.
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But these results in KO-models are species-specific and have to be considered with precaution.
Abstract
Animals and humans are exposed each day to a multitude of chemicals in the air, water and food. They have developed a battery of enzymes and transporters that facilitate the biotransformation and elimination of these compounds. Moreover, a majority of these enzymes and transporters are inducible due to the activation of xenobiotic receptors which act as transcription factors for the regulation of their target genes (such as xenobiotic metabolizing enzymes, see below §4 for the AhR). These receptors include several members of the nuclear/steroid receptor family (CAR for Constitutive Androstane Receptor, PXR for Pregnane X Receptor) but also the Aryl hydrocarbon Receptor or AhR, a member of the bHLH-PAS family (basic Helix-Loop-Helix - Period/ARNT/Single minded). In addition to the regulation of xenobiotic metabolism, numerous alternative functions have been characterized for the AhR since its discovery. These alternative functions will be described in this review along with its endogenous functions as revealed by experiments performed on knock-out animals.