Taylor D B, Gartner T K
Department of Biology, Memphis State University, Tennessee 38152.
J Biol Chem. 1992 Jun 15;267(17):11729-33.
The platelet fibrinogen (Fg) receptor (GPIIb/IIIa) is an integrin which plays a critical role in hemostasis by recognizing at least the four adhesive ligands: Fg, fibronectin (Fn), vitronectin (Vn), and von Willebrand factor (vWf). We reported that residues 309-312 of GPIIb alpha appear to comprise at least part of a Fg binding site on the Fg receptor (Gartner, T. K., and Taylor, D. B. (1990) Thromb. Res. 60, 291-309). Here we report that the peptide GPIIb alpha 300-312 (G13) inhibits platelet aggregation and binds Fg and Vn. Significantly, this peptide inhibits the adhesion of stimulated platelets to Fg, Fn, Vn, and vWf, but not the adhesion of resting platelets to Fn. Thus, GPIIb 300-312 may constitute a specific but common recognition site on GPIIb/IIIa for both LGGAKQAGDV- and RGD-containing ligands.
血小板纤维蛋白原（Fg）受体（GPIIb/IIIa）是一种整合素，通过识别至少四种黏附配体，即纤维蛋白原（Fg）、纤连蛋白（Fn）、玻连蛋白（Vn）和血管性血友病因子（vWf），在止血过程中发挥关键作用。我们曾报道，GPIIbα的309 - 312位残基似乎构成了Fg受体上Fg结合位点的至少一部分（加特纳，T.K.，和泰勒，D.B.（1990年）《血栓形成研究》60卷，291 - 309页）。在此我们报道，肽段GPIIbα300 - 312（G13）可抑制血小板聚集，并能结合Fg和Vn。值得注意的是，该肽段可抑制活化血小板与Fg、Fn、Vn和vWf的黏附，但不影响静息血小板与Fn的黏附。因此，GPIIb 300 - 312可能构成了GPIIb/IIIa上针对含LGGAKQAGDV和含RGD配体的一个特异性但共同的识别位点。
