The aryl hydrocarbon receptor, more than a xenobiotic-interacting protein

Robert Barouki1, Xavier Coumoul, Pedro M Fernandez-Salguero

  • 1INSERM, UMR-S 747, 75270 Paris Cedex 06, France. robert.barouki@univ-paris5.fr

FEBS Letters
|April 7, 2007
PubMed

Insights

The aryl hydrocarbon receptor (AhR) is crucial for xenobiotic toxicity. Recent research explores its physiological roles in normal cells, including cell growth and gene regulation.

Area of Science:

  • Biochemistry
  • Molecular Biology
  • Toxicology

Background:

  • The aryl hydrocarbon receptor (AhR) is a well-known mediator of toxic responses to environmental pollutants.
  • Its role in xenobiotic metabolism and carcinogenesis has been extensively studied.
  • Emerging research highlights the AhR's involvement in normal physiological processes.

Purpose of the Study:

  • To review the current understanding of the aryl hydrocarbon receptor's (AhR) physiological functions under normal cellular conditions.
  • To summarize research investigating the AhR's role in endogenous cellular processes beyond xenobiotic metabolism.

Main Methods:

  • Literature review of studies investigating aryl hydrocarbon receptor (AhR) function.
  • Analysis of research on AhR's involvement in cell proliferation, differentiation, gene regulation, and cell motility.
  • Synthesis of findings related to endogenous AhR activation mechanisms.

Main Results:

  • The aryl hydrocarbon receptor (AhR) is implicated in fundamental cellular activities such as proliferation and differentiation.
  • Endogenous ligands and activation pathways for the AhR are increasingly being identified.
  • AhR signaling influences gene expression, tumor development, and cell migration.

Conclusions:

  • The aryl hydrocarbon receptor (AhR) plays significant physiological roles in normal cellular functions.
  • Further research into the AhR's endogenous functions is essential for understanding both normal physiology and disease.
  • Understanding the AhR's dual role in toxicity and physiology opens new avenues for therapeutic strategies.

Related Concept Videos

Transducer Mechanism: Nuclear Receptors01:31

Transducer Mechanism: Nuclear Receptors

Nuclear receptors, or NRs, are unique transcription factors that regulate gene transcription and affect the cellular pathways involved in reproduction, development, or metabolism. Their ability to be stimulated by small lipophilic ligands and control vital cellular processes makes them ideal drug targets. Nearly 10-15% of currently prescribed drugs target these receptors.
About 48 different soluble family members of nuclear receptors are identified that can be divided into two main classes:
Drug-Receptor Interactions01:29

Drug-Receptor Interactions

Drug-receptor interaction describes the binding of receptors by drugs, but not all drug-receptor interactions result in activation and tissue response. For instance, the binding of agonists activates the receptor to generate a cellular reaction, while antagonists bind to receptors without causing their activation.
Several parameters, such as the drug's affinity for its receptor and its efficacy, which is its ability to activate the receptor, determine the drug's effect on the tissue.
The Two-State Receptor Model01:29

The Two-State Receptor Model

The two-state receptor model explains a drug's interaction with receptors, such as G protein-coupled receptors and ligand-gated ion channels, to induce or inhibit a biological response. When no natural ligands are present, a receptor exists in an equilibrium of inactive (Ri) and active (Ra) conformations. The inactive form does not produce a response, while the active form generates a basal effect known as constitutive activity.
The binding affinity of a drug determines its interaction with one...
Cell Signaling in Plants01:25

Cell Signaling in Plants

Plant cells communicate to coordinate their cycle of growth, flowering and fruiting, and activities in roots, shoots, and leaves in response to the changing environmental conditions. Plant signaling is distinct from animal signaling. Plants primarily utilize enzyme-linked receptors, whereas the largest class of cell-surface receptors in animals are G-protein coupled receptors (GPCRs). Unlike animals, receptor tyrosine kinases are rare in plants. Instead, plants have a diverse class of...
Assembly of Signaling Complexes01:30

Assembly of Signaling Complexes

Multiprotein signaling complexes are formed in a dynamic process involving protein-protein interactions at the cytoplasmic domain of transmembrane receptors or enzymatic and non-enzymatic proteins associated with the receptor. These complexes ensure the activation and propagation of intracellular signals that regulate cell functions.
Interaction domains in cell signaling
Interaction domains recognize exposed features of their binding partners containing post-translationally modified sequences,...
Internal Receptors01:31

Internal Receptors

Many cellular signals are hydrophilic and therefore cannot pass through the plasma membrane. However, small or hydrophobic signaling molecules can cross the hydrophobic core of the plasma membrane and bind to internal, or intracellular, receptors that reside within the cell. Many mammalian steroid hormones use this mechanism of cell signaling, as does nitric oxide (NO) gas.