Desulfated galactosaminoglycans are potential ligands for galectins: evidence from frontal affinity chromatography.
Galectins, a group of beta-galactoside-binding lectins, are involved in multiple functions through specific binding to their oligosaccharide ligands. No previous work has focused on their interaction with glycosaminoglycans (GAGs). In the present work, affinities of established members of human galectins toward a series of GAGs were investigated, using frontal affinity chromatography. Structurally-defined keratan sulfate (KS) oligosaccharides showed significant affinity to a wide range of galectins if Gal residue(s) remained unsulfated, while GlcNAc sulfation had relatively little effect. Consistently, galectins showed much higher affinity to corneal type I than cartilageous type II KS. Unexpectedly, galectin-3, -7, and -9 also exerted significant affinity to desulfated, GalNAc-containing GAGs, i.e., chondroitin and dermatan, but not at all to hyaluronan and N-acetylheparosan. These observations revealed that the integrity of 6-OH of betaGalNAc is important for galectin recognition of these galactosaminoglycans, which were shown, for the first time, to be implicated as potential ligands of galectins.
Iwaki
Jun
J
Lectin Application and Analysis Team, Research Center for Medical Glycoscience, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba Central 2, 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568, Japan.
Minamisawa
Toshikazu
T
Tateno
Hiroaki
H
Kominami
Junko
J
Suzuki
Kiyoshi
K
Nishi
Nozomu
N
Nakamura
Takanori
T
Hirabayashi
Jun
J
D002807:Chondroitin / Q000737:chemistry; D002846:Chromatography, Affinity; D037161:Galectins / Q000737:chemistry*; D006801:Humans; D008024:Ligands; D009844:Oligosaccharides / Q000737:chemistry*; D011134:Polysaccharides / Q000737:chemistry*; D013431:Sulfates / Q000737:chemistry*
D037161:Galectins; D008024:Ligands; D009844:Oligosaccharides; D011134:Polysaccharides; D013431:Sulfates; D002807:Chondroitin; C007815:galactosaminoglycan