The Binding Ability to Matrix Proteins and the Inhibitory Effects on Cell Adhesion of Synthetic Peptides Derived from a Conserved Sequence of Integrins

抄録

The β peptide (113-125), derived from a conserved sequence of the β subunit of integrins, was synthesized to investigate its adhesive properties to matrix proteins and the effects on cell adhesion to immobilized fibronectin. In this study, weobserved that the biotinylated β peptide was able to bind efficiently to immobilized fibronectin, fibrinogen, collagen Type I and vitronectin with different degrees of affinity. It was also demonstrated that biotinylat-ed fibronectin or fibrinogen could bind to the coated β peptide. This kind of binding, which might be non-covalent linkage, was partially blocked by coincubation with the peptide GRGDS or EDTA, but not by SDGRG. Cell adhesion experiments were performed to study the effect of the β peptide. The data showed that the β peptide partially inhibitedboth fibroblast L929 and MC3T3-E1 osteoblastic cells from adhering to immobilized fibronectin in a dosage-dependent manner. In the presence of 100μM concentration of the β peptide, the inhibition rate of cell adhesion was 34% for fibroblast L929 cells and 54. 1% for MC 3T3-E1 osteoblastic cells. This research suggeststhat the β peptide might act independently as an adhesive region of the β subunitof integrins and may occupy the cell-binding site within fibronectin.