Purification and characterization of the N-terminal domain of galectin-4 from rat small intestine

Using affinity chromatography on lactose-agarose, five beta-galactoside binding lectins of 14 to 20 kDa were detected in the rat small intestinal mucosa. The prominant proteins of 17 and 19 kDa were purified to homogeneity by 2D-electrophoresis. Direct N-terminal sequencing of the 17 kDa protein and intrachain sequencing of the 19 kDa protein produced sequences which are part of the N-terminal domain of the L-36/galectin-4. A rabbit polyclonal antibody was raised against the 19 kDa lectin, which specifically recognized the 17 and 19 kDa lectins and detected a related 36 kDa protein in human undifferentiated HT29 cells.