Aryl hydrocarbon receptor (AHR) is a ligand-activated transcription factor that mediates the biological and toxic effects of dioxin-like compounds []. Upon ligand binding, the receptor translocates into the nucleus where it heterodimerises with ARNT (AHR nuclear translocator) []. The aryl hydrocarbon receptor repressor (AHRR) competes with AHR for the binding of ARNT, and thereby repressing AHR's transcription activity [].
