GPCR Overview – Internalization
PathHunter® GPCR Internalization assays are whole cell functional assays that measure GPCR receptor recycling and desensitization. These non-imaging, non-antibody-based chemiluminescent assays provide a direct and quantitative measurement of internalized GPCR localized to intracellular endosomes and allow the fate of unlabelled, activated GPCRs to be monitored in live cells without the requirement of expensive microscopy.
Two Formats – One Simple Answer
Regardless of the biology, pharmacology, rate of internalization and/or recycling of the receptor:ligand pair being studied, DiscoveRx offers a novel, EFC-based GPCR endocytosis assay for any target to enable your drug discovery programs.
PathHunter® Total GPCR Internalization System, the large portion of β-galactosidase called Enzyme Acceptor or EA is localized exclusively to intracellular endosomes and PK is fused to the GPCR of interest. GPCR activation results in internalization of the receptor and trafficking to endosomes.
PathHunter® Activated GPCR Internalization Assays detect Arrestin-mediated GPCR internalization. In this system, the small enzyme fragment of β-galactosidase called ProLink™ (PK) is localized to intracellular endosomes and the larger complementing enzyme fragment termed Enzyme Acceptor or EA is fused to β-Arrestin. Stimulation of the receptor results in Arrestin binding to the activated GPCR, internalization of the receptor and trafficking to cellular endosomes.
In both formats, complementation of the two enzyme fragments results in an increase in enzyme activity that can be easily measured using PathHunter® Detection Reagents.
PathHunter® GPCR Internalization Advantage
- Direct functional readout – uncover novel classes of compounds like superagonists, functional antagonists
- Universal assay conditions – works across all GPCR classes and receptor families, ideal for profiling and lead optimization
- Stable cell lines – results in predictable pharmacology and reproducibility
- Chemiluminescent, gain-of-signal assays – no antibodies, radioactivity or imaging
- Standard instrumentation – no complex data analysis, normalization or pit/vesicle spot detection required
Measure Compound Efficacy and Potency Differences
DADLE reference compound for OPRD1
SNC-80 strong internalizing compound
DAMGO weakly internalizing
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* All 3 compounds are strongly internalizing
* Oxo-M more potent than Acetylcholine and Carbachol (reference compounds for M2)
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Related Products - PathHunter® GPCR Internalization Assays
PathHunter® Internalization GPCR Assays