Aryl Hydrocarbon Receptor Repressor (AHRR)

AHRR represses signal transduction by the arylhydrocarbon receptor by competing with the arylhydrocarbon receptor nuclear translocator for binding to the arylhydrocarbon receptor. Expression of the repressor is stimulated by the receptor/translocator heterodimer, thereby regulating receptor function through a negative feedback mechanism. In addition, the encoded protein can bind to nuclear factor kappa-B.

Mouse Ahrr inhibited Ahr function by competing with Ahr for dimerizing with Arnt and binding to the XRE. expression of Ahrr was induced by the Ahr-Arnt heterodimer when the latter bound to the XRE of Ahrr, i.e., Ahrr regulated Ahr function by negative feedback and affected expression of target genes induced by dioxin.