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Identification of a novel mechanism of regulation of Ah (dioxin) receptor function.

ABSTRACT: Ah receptor (AhR) is a ligand-activated transcription factor that mediates pleiotropic effects of environmental pollutants such as 2,3, 7,8-tetrachlorodibenzo-p-dioxin on host animals. In addition to induction of drug-metabolizing enzymes, the liganded AhR complex was found to activate gene expression of a factor designated AhR repressor (AhRR), which inhibits AhR function by competing with AhR for dimerizing with Arnt and binding to the XRE sequence. Thus, AhR and AhRR form a regulatory circuit in the xenobiotic signal transduction pathway and provide a novel mechanism of regulation of AhR function that may determine tissue-specific sensitivity to environmental pollutants.

SUBMITTER: Mimura J

PROVIDER: S-EPMC316371 | biostudies-literature | 1999 Jan

REPOSITORIES: biostudies-literature

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Identification of a novel mechanism of regulation of Ah (dioxin) receptor function.

Mimura J J Ema M M Sogawa K K Fujii-Kuriyama Y Y

Genes & development 19990101 1

Ah receptor (AhR) is a ligand-activated transcription factor that mediates pleiotropic effects of environmental pollutants such as 2,3, 7,8-tetrachlorodibenzo-p-dioxin on host animals. In addition to induction of drug-metabolizing enzymes, the liganded AhR complex was found to activate gene expression of a factor designated AhR repressor (AhRR), which inhibits AhR function by competing with AhR for dimerizing with Arnt and binding to the XRE sequence. Thus, AhR and AhRR form a regulatory circuit ...[more]

PMID: 9887096

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CH223191 is a ligand-selective antagonist of the Ah (Dioxin) receptor.

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