The structure of the oligosaccharides of alpha3beta1 integrin from human ureter epithelium [HCV29] cell line

There is a growing line of evidence that glycosylation of a and β subunits is impor­tant for the function of integrins. Integrin a3β1, from human ureter epithelium cell — line HCV29, was isolated by affinity chromatography on laminin GD6 peptide. Char­acterization of its carbohydrate moieties was carried out using sodium dodecyl sul- fate/polyacrylamide gel electrophoresis followed by Western blotting on Immobilon P and on-blot deglycosylation with peptide .-glycosidase-F. Profiles of N-glycans for each subunit were obtained by matrix-assisted laser desorption/ionization mass spec- trometry. Our findings demonstrated, in both subunits of integrin a3β1, the presence of complex type oligosaccharides with a wide heterogeneity. Bi- tri- and tetra- antennary structures were the most common, while high-mannose type structures were minor. Also the presence of short poly-. -acetyllactosamine entities was shown. These results show that while the predominant oligosaccharides of both subunits are identical, some slight differences between them do exist.