We hypothesized that NF-κB is an essential modulator to prevent cholestasis in Mdr2−/− mice, because protein levels and hepatocyte nuclear translocation of phosphorylated NF-κB P65 were markedly elevated in the liver tissues of Mdr2−/− DSS animals (Fig. 5a, Supplementary Fig. 7a–c), and RNA-seq data showed a pronounced negative correlation between Nfκb and genes involved in BA metabolism (Fig. 5b). This evidence concerns the gene NFKB1 and cholestasis.