Santoro S A, Lawing W J
Cell. 1987 Mar 13;48(5):867-73. doi: 10.1016/0092-8674(87)90083-3.
Two distinct sequences of amino acids, RGDS and HHLGGAKQAGDV, each inhibit the binding of fibrinogen, fibronectin, and von Willebrand factor to the platelet membrane glycoprotein IIb-IIIa complex. We have employed radiolabeled, photoactivatable aryl azide derivatives of the two sequences to explore the relationship between the binding sites for these peptides on the glycoprotein IIb-IIIa complex. Each probe specifically labeled only the glycoprotein IIb-IIIa complex of intact platelets. Since each peptide inhibited labeling of the receptor complex by the other, the peptides compete for binding sites on the receptor complex. However, the binding sites do not appear to be identical. Whereas the RGDS probe specifically labeled both glycoproteins IIb and IIIa, the HHLGGAKQA-GDV probe specifically labeled only glycoprotein IIb.
两种不同的氨基酸序列，RGDS和HHLGGAKQAGDV，各自都能抑制纤维蛋白原、纤连蛋白和血管性血友病因子与血小板膜糖蛋白IIb-IIIa复合物的结合。我们利用这两种序列的放射性标记、可光活化的芳基叠氮衍生物，来探究这些肽在糖蛋白IIb-IIIa复合物上的结合位点之间的关系。每种探针仅特异性标记完整血小板的糖蛋白IIb-IIIa复合物。由于每种肽都能抑制另一种肽对受体复合物的标记，所以这些肽在受体复合物上竞争结合位点。然而，这些结合位点似乎并不相同。RGDS探针特异性标记糖蛋白IIb和IIIa，而HHLGGAKQA-GDV探针仅特异性标记糖蛋白IIb。
