Monitoring Gq-coupled receptor response through inositol phosphate quantification with the IP-One assay
- PMID: 22646860
- DOI: 10.1517/17460441.2011.608658
Monitoring Gq-coupled receptor response through inositol phosphate quantification with the IP-One assay
Abstract
Introduction: G-protein-coupled receptors (GPCRs) are transmembrane proteins that play a key role in the signal transduction of extracellular stimuli. GPCRs associate to a complex assembly of intracellular proteins regulating a large variety of signaling pathways. In particular, the production of inositol 1,4,5 triphosphate (IP3) signs the activation of Gq-coupled receptors. However, its very short half-life makes its assessment too challenging for drug screening operations and the monitoring of calcium release, triggered by IP3, has been extensively used as a downstream readout of this signaling pathway. Recently, a new homogeneous time-resolved fluorescence (HTRF) assay, detecting a downstream metabolite of IP3, inositol monophosphate (IP1), has overcome the drawbacks of the IP3 quantification, allowing its use in primary or secondary screening.
Areas covered: This review provides an overview of the use of the IP-One assay in screening processes, providing comparisons with results obtained with other existing techniques traditionally used to investigate Gq-coupled receptors. Moreover, the review highlights two key features of the IP-One assay, the discrimination of slow acting compounds and the characterization of inverse agonists, which are impossible to achieve using calcium release.
Expert opinion: The IP-One assay is well established to perform screening in the pharmaceutical industry. A number of criteria can be taken into account, including the impact of the sensitivity improvement of the assay, to position the IP-One assay in the different stages of the drug screening process. Moreover, the IP-One assay can be used as a valuable solution to investigate new research concepts such as ligand-biased signaling or receptor heteromerization.
Similar articles
-
Quantifying Gq Signaling Using the IP1 Homogenous Time-Resolved Fluorescence (HTRF) Assay.Methods Mol Biol. 2025;2861:23-32. doi: 10.1007/978-1-0716-4164-4_2. Methods Mol Biol. 2025. PMID: 39395094
-
D-myo-inositol 1-phosphate as a surrogate of D-myo-inositol 1,4,5-tris phosphate to monitor G protein-coupled receptor activation.Anal Biochem. 2006 Nov 1;358(1):126-35. doi: 10.1016/j.ab.2006.08.002. Epub 2006 Aug 30. Anal Biochem. 2006. PMID: 16965760
-
Comparison on functional assays for Gq-coupled GPCRs by measuring inositol monophospate-1 and intracellular calcium in 1536-well plate format.Curr Chem Genomics. 2008 Jul 11;1:70-8. doi: 10.2174/1875397300801010070. Curr Chem Genomics. 2008. PMID: 20161830 Free PMC article.
-
Regulation of inositol phospholipid and inositol phosphate metabolism in chemoattractant-activated human polymorphonuclear leukocytes.J Cell Biochem. 1987 Dec;35(4):345-59. doi: 10.1002/jcb.240350409. J Cell Biochem. 1987. PMID: 3126197 Review.
-
GPCR responses in vascular smooth muscle can occur predominantly through dual transactivation of kinase receptors and not classical Gαq protein signalling pathways.Life Sci. 2013 May 30;92(20-21):951-6. doi: 10.1016/j.lfs.2013.03.017. Epub 2013 Apr 9. Life Sci. 2013. PMID: 23583575 Review.
Cited by
-
Delineation of the GPRC6A receptor signaling pathways using a mammalian cell line stably expressing the receptor.J Pharmacol Exp Ther. 2013 Nov;347(2):298-309. doi: 10.1124/jpet.113.206276. Epub 2013 Sep 5. J Pharmacol Exp Ther. 2013. PMID: 24008333 Free PMC article.
-
A Broad G Protein-Coupled Receptor Internalization Assay that Combines SNAP-Tag Labeling, Diffusion-Enhanced Resonance Energy Transfer, and a Highly Emissive Terbium Cryptate.Front Endocrinol (Lausanne). 2015 Nov 9;6:167. doi: 10.3389/fendo.2015.00167. eCollection 2015. Front Endocrinol (Lausanne). 2015. PMID: 26617570 Free PMC article.
-
Optogenetic induction of hibernation-like state with modified human Opsin4 in mice.Cell Rep Methods. 2022 Nov 14;2(11):100336. doi: 10.1016/j.crmeth.2022.100336. eCollection 2022 Nov 21. Cell Rep Methods. 2022. PMID: 36452866 Free PMC article.
-
Quantifying Gq Signaling Using the IP1 Homogenous Time-Resolved Fluorescence (HTRF) Assay.Methods Mol Biol. 2025;2861:23-32. doi: 10.1007/978-1-0716-4164-4_2. Methods Mol Biol. 2025. PMID: 39395094
-
In Vivo Non-radioactive Assessment of mGlu5 Receptor-Activated Polyphosphoinositide Hydrolysis in Response to Systemic Administration of a Positive Allosteric Modulator.Front Pharmacol. 2018 Jul 31;9:804. doi: 10.3389/fphar.2018.00804. eCollection 2018. Front Pharmacol. 2018. PMID: 30108503 Free PMC article.
LinkOut - more resources
Full Text Sources
