Characterization of a 21 amino acid peptide sequence of the laminin G2 domain that is involved in HNK-1 carbohydrate binding and cell adhesion.
The N-linked HNK-1 carbohydrate expressed by several recognition molecules mediates the adhesion of early post-natal cerebellar neurons to the G2 domain of the terminal globular domain of the laminin alpha 1 chain (H. Hall et al., submitted). To define this binding site more precisely, G2-derived synthetic peptides were used for binding and competition studies. Peptide 5-G2, comprising the amino acid residues 3431-3451 of G2, inhibited the interaction between the HNK-1-carrying glycolipid and laminin in a concentration-dependent and saturable manner. Peptides which overlap only partially with this sequence interfered less. Peptides comprising other amino acid sequences from G2, and peptides derived from G1 and G3 or a scrambled version of peptide 5-G2, did not show significant effects. Direct binding of peptide 5-G2 to the HNK-1 glycolipid was also demonstrated. Furthermore, peptide 5-G2 interfered in a concentration-dependent and saturable manner with the adhesion of early postnatal cerebellar neurons to laminin. These observations indicate that amino acid residues 3431-3451 of the laminin G2 domain are involved in HNK-1 carbohydrate-mediated cell adhesion.
Hall
H
H
Department of Neurobiology, Swiss Federal Institute of Technology, Zürich.
Vorherr
T
T
Schachner
M
M
D000595:Amino Acid Sequence; D000818:Animals; D000911:Antibodies, Monoclonal; D001665:Binding Sites; D018959:CD57 Antigens / Q000378:metabolism*; D002448:Cell Adhesion / Q000187:drug effects; D002531:Cerebellum / Q000166:cytology; D007140:Immunoglobulin Fab Fragments; D007797:Laminin / Q000737:chemistry* / Q000378:metabolism*; D051379:Mice; D008813:Mice, Inbred ICR; D008969:Molecular Sequence Data; D009474:Neurons / Q000378:metabolism; D010446:Peptide Fragments / Q000737:chemistry* / Q000378:metabolism* / Q000494:pharmacology; D013329:Structure-Activity Relationship
D000911:Antibodies, Monoclonal; D018959:CD57 Antigens; D007140:Immunoglobulin Fab Fragments; D007797:Laminin; D010446:Peptide Fragments