Number and brightness analysis to study spatio-temporal distribution of the angiotensin II AT1 and the endothelin-1 ETA receptors: Influence of ligand binding

Publication date: Available online 6 March 2019Source: Biochimica et Biophysica Acta (BBA) - General SubjectsAuthor(s): Nadir Planes, Michelle A. Digman, Patrick P.M.L. Vanderheyden, Enrico Gratton, Catherina Caballero-GeorgeAbstractThe angiotensin II AT1 and the endothelin 1 ETA receptors play a crucial role in the pathogenesis of cardiovascular diseases like hypertension, heart failure, stroke, pulmonary hypertension, and cardiac hypertrophy. Both receptors are members of the rhodopsion-like superfamily of G protein-coupled receptors which can exist as monomers, dimers, and higher order aggregates.Recently, oligomerization of these two receptors have been described by several biophysical methods based mainly on luminescence and fluorescence energy transfer. Since this oligomerization can occur either spontaneously or it can be induced by ligand-binding, the aim of this work was to address whether the oligomerization of these receptors occurs upon ligand-binding. For this purpose the Number and Brightness analysis, a method that allows the identification, localization, and quantification of protein aggregates in the plasma membrane of a single cell, was used. An advantage of this method is that it is not limited to certain dyes specially required for Fluorescence Resonance Energy Transfer measurements.Our results showed that stably transfected angiotensin II AT1 receptors and transiently transfected endothelin 1 ETA receptors, were found as monomeric, dimeric, and tetrameric...
Source: Biochimica et Biophysica Acta (BBA) General Subjects - Category: Biochemistry Source Type: research