Fluorescence Correlation Spectroscopy in Drug Discovery: Study of Alexa532-Endothelin 1 Binding to the Endothelin ET<SUB>A</SUB> Receptor to Describe the Pharmacological Profile of Natural Products

Abstract

Fluorescence correlation spectroscopy and the newly synthesized Alexa532-ET1 were used to study the dynamics of the endothelin ETA receptor-ligand complex alone and under the influence of a semisynthetic selective antagonist and a fungal extract on living A10 cells. Dose-dependent increase of inositol phosphate production was seen for Alexa532-ET1, and its binding was reduced to 8% by the selective endothelin ETA antagonist BQ-123, confirming the specific binding of Alexa532-ET1 to the endothelin ETA receptor. Two different lateral mobilities of the receptor-ligand complexes within the cell membrane were found allowing the discrimination of different states for this complex. BQ-123 showed a strong binding affinity to the "inactive" receptor state characterized by the slow diffusion time constant. A similar effect was observed for the fungal extract, which completely displaced Alexa532-ET1 from its binding to the "inactive" receptor state. These findings suggest that both BQ-123 and the fungal extract act as inverse agonists.

Description

Keywords

Citation

Caballero-George, Catherina, Sorkalla, Thomas, Jakobs, Daniel, Bolanos, Jessica, Raja, Huzefa, Shearer, Carol, Bermingham, Eldredge, and Haeberlein, Hanns. 2012. "<a href="https://repository.si.edu/handle/10088/21220">Fluorescence Correlation Spectroscopy in Drug Discovery: Study of Alexa532-Endothelin 1 Binding to the Endothelin ET<SUB>A</SUB> Receptor to Describe the Pharmacological Profile of Natural Products</a>." <em>Scientific World Journal</em>, 524169–524169. <a href="https://doi.org/10.1100/2012/524169">https://doi.org/10.1100/2012/524169</a>.

Endorsement

Review

Supplemented By

Referenced By