Abstract
The tripeptide Arg-Gly-Asp acid (RGD) is a protein sequence in the binding of proteins to cell surfaces, and is involved in various biological processes such as cell adhesion to the extracellular matrix, platelet activation, hemostasis, etc. The C2 domain of the Von Willebrand Factor (VWF), containing the RGD motif, plays an important role in the initial homeostasis process. It binds to the αIIbβ3 integrin and stimulates platelet aggregation. We have investigated, using the molecular Dynamic (MD) simulation method, the effect of the RGD-peptide length, and temperature variation, on the binding to the αIIbβ3 integrin receptor. We examined 10 different structural modes of the αIIbβ3 at three different temperatures; 237 K, 310 K and 318 K. Our findings show that the amino acids that form a binding pocket include Asp224, Tyr234, Ser226, Tyr190, Tyr189, Trp260, Trp262, Asp259, Lys253, Arg214, Asp217, Ser161 and Ala218 and that the ligand-receptor interaction was increased at higher temperatures. It was also found that the increase in the number of ligands’ amino acids and their types (% glycine) plays an important role in the stability, conformation, and ligand-receptor interaction.
Communicated by Ramaswamy H. Sarma
Acknowledgements
This paper is part of the Ph.D. thesis in nanomedicine by Hossein Arzani, supported by a grant from the Research Council of the Shahid Beheshti University of Medical Sciences.
Disclosure statement
No potential conflict of interest was reported by the authors.