Related Experiment Video
Updated: Aug 5, 2026

Measuring G-protein-coupled Receptor Signaling via Radio-labeled GTP Binding
Published on: June 9, 2017
G protein signaling capabilities at the bradykinin 2 receptor
Shradha V Darira1,2,3, Laurie P Sutton4
1Department of Biological Sciences, University of Maryland Baltimore County, Baltimore, MD, 21250, USA.
Abstract:
The bradykinin 2 receptor (B2R) is one of two members of the kinin receptor family and is a G protein-coupled receptor (GPCR) that regulates important physiological processes including pain, inflammation, and cardiovascular homeostasis. Functionally, B2R is activated by the kinin peptides, bradykinin and kallidin. Carboxypeptidase cleavage of bradykinin and kallidin results in the formation of des-Arg9-bradykinin (DABK) and des-Arg10-kallidin (DAKD) respectively, which are classically described as agonists of the bradykinin 1 receptor (B1R), the other member of the kinin family. Affinity binding studies have reported that DABK and DAKD can also bind to B2R. Upon activation, B2R signals through the recruitment of heterotrimeric G proteins, and earlier work has highlighted the promiscuous G protein coupling to B2R in response to bradykinin. However, a comprehensive G protein activation profile of the B2R receptor when activated by the other endogenous agonists has not yet been established. In this study, we used Bioluminescence Resonance Energy Transfer (BRET)-based in vitro assays to monitor the coupling of 14 different Gα proteins upon B2R activation. Our results show that there is a shift in G protein activation profiles and kinetics among the different peptides. By analyzing responses across a range of agonist concentrations, we further identified biased signaling among these peptides, with differential activation of specific Gα subtypes. These results improve understanding of intracellular mechanisms through which the kinin system regulates different aspects of its physiological role and provide valuable information for the design of drugs targeting the kinin receptors.
More Related Videos
09:21BRET-based G Protein Biosensors for Measuring G Protein-Coupled Receptor Activity in Live Cells
Published on: November 7, 2025
07:41A Kinetic Fluorescence-based Ca2+ Mobilization Assay to Identify G Protein-coupled Receptor Agonists, Antagonists, and Allosteric Modulators
Published on: February 20, 2018
Related Concept Videos
Amplifying Signals via Enzymatic Cascade
Activation and Inactivation of G Proteins
Amplifying Signals via Second Messengers
GPCRs Regulate Adenylyl Cylase Activity
Two...
G-protein Coupled Receptors
G-protein Coupled Receptors