Insights into AT₁ Receptor Activation through AngII Binding Studies

This study investigates the binding of angiotensin II (AngII) to the angiotensin II type 1 receptor (AT₁R), taking into consideration several known activation elements that have been observed for G-protein-coupled receptors (GPCRs). In order to determine the crucial interactions of AngII upon binding, several MD simulations were implemented using AngII conformations derived from experimental data (NMR ROEs) and in silico flexible docking methodologies. An additional goal was to simulate the induced activation mechanism and examine the already known structural rearrangements of GPCRs upon activation. Performing MD simulations to the AT₁R – AngII – lipids complex, a series of dynamic changes in the topology of AngII and the intracellular part of the receptor were observed. Overall, the present study proposes a complete binding profile of AngII to the AT₁R, as well as the key transitional elements of the receptor and the agonist peptide upon activation through NMR and in silico studies.