Activation of the Ahr signalling pathway by polychlorobiphenyls causes a marked induction of cytochrome P450 only after depletion of vitellogenin in Sparus aurata

► PCBs active Ahr causing a marked induction of CYP1A1 only after depletion of Vtg. ► The data show the systemic exploration of the ubiquitin system as a target of environmental. ► PCBs modulate the activity of receptors and display cross-talk between the pathways involved.