MUC5AC and colitis: Then, PAPS translocases Slc35b3 are responsible for transporting PAPS to Golgi apparatus to participate in the mucin sulfation reaction.27–29 Intestinal deficiency of Papss2 has been reported to compromise mucin sulfation and gut barrier on colitis challenge.30 In our study, the RNA sequencing data showed a significant increase in Papss2 and Slc35b3 expression in IAA-treated colitis mice (Figure 3d).