Feige J J, Baird A
Salk Institute, Laboratories for Neuroendocrinology, La Jolla, California 92138-9216.
J Biol Chem. 1988 Oct 5;263(28):14023-9.
We have examined the glycosylation of the basic fibroblast growth factor (bFGF) receptor to determine whether carbohydrates contribute to receptor structure and function. Using a combination of cross-linking and radioreceptor assays, we demonstrated that the two bFGF receptors in baby hamster kidney cells have protein cores of 100 and 125 kDa. They are glycosylated to high mannose forms of 115 and 140 kDa and further processed to their mature forms of 130 and 150 kDa. Because peptide:N-glycosidase F, but not endo-alpha-N-acetylgalactosamidase can reduce the size of the bFGF receptors, the carbohydrate residues of the receptor appear all N-linked. The inability of deglycosylated receptors to bind 125I-bFGF supports the notion that the carbohydrate residues are required for receptor function. Furthermore, the capacity of the wheat germ agglutinin lectin to inhibit 125I-bFGF binding and the biological activity of bFGF suggests that N-acetylglucosamine residues are functionally significant components of the receptor.
我们检测了碱性成纤维细胞生长因子（bFGF）受体的糖基化情况，以确定碳水化合物是否对受体的结构和功能有影响。通过交联和放射受体分析相结合的方法，我们证明了幼仓鼠肾细胞中的两种bFGF受体具有100 kDa和125 kDa的蛋白质核心。它们被糖基化为115 kDa和140 kDa的高甘露糖形式，并进一步加工成130 kDa和150 kDa的成熟形式。由于肽：N-糖苷酶F而非内切α-N-乙酰半乳糖胺酶可减小bFGF受体的大小，因此受体的碳水化合物残基似乎均为N-连接型。去糖基化受体无法结合125I-bFGF，这支持了碳水化合物残基是受体功能所必需的这一观点。此外，麦胚凝集素抑制125I-bFGF结合以及bFGF生物活性的能力表明，N-乙酰葡糖胺残基是受体的功能重要组成部分。
