Required for MUC2 post-transcriptional synthesis and secretion. May play a role in the production of mucus by intestinal cells (By similarity). Proto-oncogene that may play a role in cell migration, cell differentiation and cell growth. Promotes cell adhesion (PubMed:23274113). {ECO:0000250, ECO:0000269|PubMed:18199544, ECO:0000269|PubMed:23274113}. This is the function of Ensembl gene identifier ENSG00000106541 (AGR2, anterior gradient 2, protein disulphide isomerase family member).