Hall H, Vorherr T, Schachner M
Department of Neurobiology, Swiss Federal Institute of Technology, Zürich.
Glycobiology. 1995 Jun;5(4):435-41. doi: 10.1093/glycob/5.4.435.
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.
几种识别分子所表达的N-连接HNK-1碳水化合物介导了出生后早期小脑神经元与层粘连蛋白α1链末端球状结构域的G2结构域的黏附（H. Hall等人，待发表）。为了更精确地确定这个结合位点，使用了源自G2的合成肽进行结合和竞争研究。包含G2的氨基酸残基3431 - 3451的肽5-G2以浓度依赖性和饱和性方式抑制携带HNK-1的糖脂与层粘连蛋白之间的相互作用。仅与该序列部分重叠的肽干扰较小。包含来自G2的其他氨基酸序列的肽，以及源自G1和G3的肽或肽5-G2的 scrambled 版本，均未显示出显著效果。还证实了肽5-G2与HNK-1糖脂的直接结合。此外，肽5-G2以浓度依赖性和饱和性方式干扰出生后早期小脑神经元与层粘连蛋白的黏附。这些观察结果表明，层粘连蛋白G2结构域的氨基酸残基3431 - 3451参与了HNK-1碳水化合物介导的细胞黏附。
