Site‐specific inhibition of integrin αvβ3‐vitronectin association by a ser‐asp‐val sequence through an Arg‐Gly‐Asp‐binding site of the integrin

Y Choi, E Kim, Y Lee, MH Han, IC Kang - Proteomics, 2010 - Wiley Online Library
Y Choi, E Kim, Y Lee, MH Han, IC Kang
Proteomics, 2010Wiley Online Library
A functional proteomic technology using protein chip and molecular simulation was used to
demonstrate a novel biomolecular interaction between P11, a peptide containing the Ser‐
Asp‐Val (SDV) sequence and integrin αvβ3. P11 (HSDVHK) is a novel antagonistic peptide
of integrin αvβ3 screened from hexapeptide library through protein chip system. An in silico
docking study and competitive protein chip assay revealed that the SDV sequence of P11 is
able to create a stable inhibitory complex onto the vitronectin‐binding site of integrin αvβ3 …
Abstract
A functional proteomic technology using protein chip and molecular simulation was used to demonstrate a novel biomolecular interaction between P11, a peptide containing the Ser‐Asp‐Val (SDV) sequence and integrin αvβ3. P11 (HSDVHK) is a novel antagonistic peptide of integrin αvβ3 screened from hexapeptide library through protein chip system. An in silico docking study and competitive protein chip assay revealed that the SDV sequence of P11 is able to create a stable inhibitory complex onto the vitronectin‐binding site of integrin αvβ3. The Arg‐Gly‐Asp (RGD)‐binding site recognition by P11 was site specific because the P11 was inactive for the complex formation of a denatured form of integrin–vitronectin. P11 showed a strong antagonism against αvβ3‐GRGDSP interaction with an IC50 value of 25.72±3.34 nM, whereas the value of GRGDSP peptide was 1968.73±444.32 nM. The binding‐free energies calculated from the docking simulations for each P11 and RGD peptide were −3.99 and −3.10 kcal/mol, respectively. The free energy difference between P11 and RGD corresponds to approximately a 4.5‐fold lower Ki value for the P11 than the RGD peptide. The binding orientation of the docked P11 was similar to the crystal structure of the RGD in αvβ3. The analyzed docked poses suggest that a divalent metal–ion coordination was a common driving force for the formation of both SDV/αvβ3 and RGD/αvβ3 complexes. This is the first report on the specific recognition of the RGD‐binding site of αvβ3 by a non‐RGD containing peptide using a computer‐assisted proteomic approach.
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