Comparative lectinology: Delineating glycan-specificity profiles of the chicken galectins using neoglycoconjugates in a cell assay

Abstract

A major aspect of carbohydrate-dependent galectin functionality is their cross-linking capacity. Using a cell surface as biorelevant platform for galectin binding and a panel of 40 glycans as sensor part of a fluorescent polyacrylamide neoglycopolymer for profiling galectin reactivity, properties of related proteins can be comparatively analyzed. The group of the chicken galectins (CGs) is an especially suited system toward this end due to its relatively small size, compared with mammalian galectins. The experiments reveal particularly strong reactivity toward N-acetyllactosamine repeats for all tested CGs and shared reactivity of CG-1A and CG-2 to histo-blood group ABH determinants. In cross-species comparison, CG-1B's properties closely resembled those of human galectin-1, as was the case for the galectin-2 (but not galectin-3) ortholog pair. Although binding-site architectures are rather similar, reactivity patterns can well differ.