Identification of the sulfated monosaccharides of GlyCAM-1, an endothelial-derived ligand for L-selectin
Biochemistry, 1994•ACS Publications
Revised Manuscript Received February 10, 1994s abstract: L-Selectin, a receptor bearing a
C-type lectin domain, mediates the initial attachment of lymphocytes to high endothelial
venules of lymph nodes. One of the endothelial-derived ligands for L-selectin is GlyCAM-1
(previously known as Sgp50), a mucin-like glycoprotein with sulfated, sialylated, and
fucosylated O-linked oligosaccharidechains. Sialylation, sulfation, and fucosylation appear
to be required for the avid interaction of this ligand with L-selectin, but the exact …
C-type lectin domain, mediates the initial attachment of lymphocytes to high endothelial
venules of lymph nodes. One of the endothelial-derived ligands for L-selectin is GlyCAM-1
(previously known as Sgp50), a mucin-like glycoprotein with sulfated, sialylated, and
fucosylated O-linked oligosaccharidechains. Sialylation, sulfation, and fucosylation appear
to be required for the avid interaction of this ligand with L-selectin, but the exact …
Revised Manuscript Received February 10, 1994s abstract: L-Selectin, a receptor bearing a C-type lectin domain, mediates the initial attachment of lymphocytes to high endothelial venules of lymph nodes. One of the endothelial-derived ligands for L-selectin is GlyCAM-1 (previously known as Sgp50), a mucin-like glycoprotein with sulfated, sialylated, and fucosylated O-linked oligosaccharidechains. Sialylation, sulfation, and fucosylation appear to be required for the avid interaction of this ligand with L-selectin, but the exact carbohydrate structures involved in recognition remain undefined. In this study, we examine the nature of the sulfate-modified carbohydrates ofGlyCAM-1. GlyCAM-1 was metabolically labeled in lymph node organ culturewith 35S04 and a panel of tritiated carbohydrate precursors. Mild hydrolysis conditions were established that released sulfated oligosaccharides without cleavage of sulfate esters. Low molecular weight and singly charged fragments, obtained by a combination of gel filtration and anion-exchange chromatography, were analyzed. The structural identification of the fragments relied on the use of a variety of radiolabeledsugar precursors, further chemical and enzymatic hydrolysis, and high-pH anion-exchange chromatography analysis. Sulfated constituents of GlyCAM-1 were identified as Gal-6-SC> 4, GlcNAc-6-SC> 4,(S04-6) Gal/31—* 4GlcNAc, and Gal/31—*-4 (S04-6) GlcNAc. In the accompanying paper [Hemmerich, S., & Rosen, S. D.(1994) Biochemistry 33, 4830-4835] evidence is presented that (S04-6) Gal/? l—>-4GlcNAc formsthe core of a sulfated sialyl Lewis x structure that maycomprise a recognition determinant on GlyCAM-1.
L-Selectin is a primary lymphocyte adhesion molecule involved in lymphocyte binding to high endothelial venules (HEV) 1 of lymph nodes during lymphocyte recirculation (Gallatin et al., 1983). The widespread distributionof L-selectin on all classes of leukocytes underlies its more general function in a broad spectrum of leukocyte-endothelial interactions [reviewed in Picker and Butcher (1992) andRosen
ACS Publications