Carbohydrate recognition in the peripheral nervous system: a calcium-dependent membrane binding site for HNK-1 reactive glycolipids potentially involved in Schwann cell adhesion.
The carbohydrate determinants recognized by the HNK-1 antibody are potential cell-cell recognition ligands in the peripheral nervous system (PNS). The HNK-1 reactive sulfoglucuronylneolacto (SGNL) glycolipids specifically support Schwann cell adhesion, suggesting the presence of a cell surface receptor specific for SGNL-oligosaccharides. We directly probed PNS membranes for receptors complementary to SGNL determinants using a synthetic radioligand consisting of radioiodinated serum albumin derivatized with multiple SGNL-oligosaccharides. A high-affinity, saturable, calcium-dependent binding site for this ligand was found in PNS myelin membranes. Binding activity was carbohydrate-specific (most potently inhibited by SGNL-lipids compared to other glycolipids) and PNS-specific (absent from comparable central nervous system membranes). The SGNL-specific binding activity on PNS membranes reported here may be involved in peripheral myelination or myelin stabilization.
Needham
L K
LK
Department of Pharmacology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205.
Schnaar
R L
RL
D000818:Animals; D001665:Binding Sites / Q000187:drug effects; D002118:Calcium / Q000494:pharmacology; D002240:Carbohydrate Sequence; D002448:Cell Adhesion; D015815:Cell Adhesion Molecules / Q000737:chemistry; D002462:Cell Membrane / Q000378:metabolism; D004285:Dogs; D005915:Globosides / Q000494:pharmacology; D006017:Glycolipids / Q000276:immunology / Q000378:metabolism*; D008969:Molecular Sequence Data; D009186:Myelin Sheath / Q000737:chemistry* / Q000187:drug effects / Q000378:metabolism; D010525:Peripheral Nerves / Q000737:chemistry*; D011869:Radioligand Assay; D012583:Schwann Cells / Q000737:chemistry / Q000378:metabolism*; D012584:Sciatic Nerve / Q000737:chemistry; D013433:Sulfoglycosphingolipids / Q000494:pharmacology
D015815:Cell Adhesion Molecules; D005915:Globosides; D006017:Glycolipids; D013433:Sulfoglycosphingolipids; C024032:globotetraosylceramide; D002118:Calcium