1. BRET-Based Biosensors to Measure Agonist Efficacies in Histamine H 1 Receptor-Mediated G Protein Activation, Signaling and Interactions with GRKs and β-Arrestins.
- Author
-
Verweij EWE, Bosma R, Gao M, van den Bor J, Al Araaj B, de Munnik SM, Ma X, Leurs R, and Vischer HF
- Subjects
- Energy Transfer, G-Protein-Coupled Receptor Kinases metabolism, GTP-Binding Proteins metabolism, HEK293 Cells, Humans, Receptors, G-Protein-Coupled metabolism, Receptors, Histamine H1 metabolism, beta-Arrestins metabolism, Biosensing Techniques, Histamine pharmacology
- Abstract
The histamine H
1 receptor (H1 R) is a G protein-coupled receptor (GPCR) and plays a key role in allergic reactions upon activation by histamine which is locally released from mast cells and basophils. Consequently, H1 R is a well-established therapeutic target for antihistamines that relieve allergy symptoms. H1 R signals via heterotrimeric Gq proteins and is phosphorylated by GPCR kinase (GRK) subtypes 2, 5, and 6, consequently facilitating the subsequent recruitment of β-arrestin1 and/or 2. Stimulation of a GPCR with structurally different agonists can result in preferential engagement of one or more of these intracellular signaling molecules. To evaluate this so-called biased agonism for H1 R, bioluminescence resonance energy transfer (BRET)-based biosensors were applied to measure H1 R signaling through heterotrimeric Gq proteins, second messengers (inositol 1,4,5-triphosphate and Ca2+ ), and receptor-protein interactions (GRKs and β-arrestins) in response to histamine, 2-phenylhistamines, and histaprodifens in a similar cellular background. Although differences in efficacy were observed for these agonists between some functional readouts as compared to reference agonist histamine, subsequent data analysis using an operational model of agonism revealed only signaling bias of the agonist Br-phHA-HA in recruiting β-arrestin2 to H1 R over Gq biosensor activation.- Published
- 2022
- Full Text
- View/download PDF