Rat Mrp2 gene expression is regulated by an interleukin-1β-stimulated biphasic response with enhanced transcription and subcellular shuttling of YB-1

YB-1 is activated during the hepatic acute phase response. IL-1β promotes a rapid nuclear YB-1 protein shuttling in hepatoma cells within 90 min and a transcriptional induction thereafter. This biphasic response may explain the IL-1β-mediated suppression of Mrp2 expression in endotoxemic rats.