| Autor: |
Annie Andrieux, Gérard Marguerie, J J Ryckewaert, Mark H. Ginsberg, Agnès Chapel, G Hudry-Clergeon, Edward F Plow |
| Rok vydání: |
1989 |
| Předmět: |
|
| Zdroj: |
Journal of Biological Chemistry. 264:9258-9265 |
| ISSN: |
0021-9258 |
| DOI: |
10.1016/s0021-9258(18)60523-x |
| Popis: |
Platelet membrane GPIIbIIIa is a member of the family receptors named integrins that recognize RGD sequences in their ligands. GPIIbIIIa interacts with at least three different adhesive ligands: fibrinogen, fibronectin, and von Willebrand factor. These interactions are inhibited by RGD-containing peptides and by peptides corresponding to a sequence unique to fibrinogen in the COOH-terminal domain of its γ chain (HLGGAKQAGDV). Two RGD sequences are present in fibrinogen Aα chain: an RGDS sequence at A α 572–575, and an RGDF sequence at Aα 95–98. Polyclonal antibodies raised against the RGDF sequence and the γ COOH-terminal domain both reacted specifically with fibrinogen in solid phase enzyme-linked immunosorbent assays and immunoprecipitated the protein in solution. The Fab fragments prepared from these antibodies inhibited fibrinogen-platelet interaction and aggregation. These results demonstrate that these two sequences are both accessible within the fibrinogen molecule and are both implicated in ligand binding and cell-cell interaction. In addition, by further examining the interaction of the γ chain peptide with platelets, it was found that RGDF and the γ peptide produced a similar dose-dependent inhibition of the binding of the labeled γ peptide to ADP-stimulated platelets. These results provide evidence that the RGDF sequence present at the Aα 95–98 constitutes with the γ 401–411 sequence two recognition sites interacting with the same site or with mutually exclusive sites on GPIIbIIIa. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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