G-protein signaling

As the largest family of cell surface receptors, G-protein-coupled receptors (GPCR) are involved in over one third of all drug screening efforts.

Cisbio’s expertise in GPCR began more than 20 years ago. Now, you can choose from over 100 products and learn from supporting scientific content to explore the GPCR world.

G proteins simplified pathway

GPCR signals through G proteins, which get their name from the fact that they bind the guanine nucleotides GDP and GTP. The most well-known G proteins are Gs, Gq, and Gi.

Gs- and Gi-coupled receptors

Cyclic AMP (cyclic adenosine 3’,5’-monophosphate, or simply cAMP) is one of the most important GPCR intracellular mediators. In many cell types, cAMP production often results from the regulation of adenylate cyclase by the Gα subunit of heterotrimeric G-proteins. Gαs-coupled GPCRs act to positively stimulate the activity of adenylate cyclase, resulting in an increase in cellular cAMP. Gαi-coupled GPCRs lead to a negative regulation of adenylate cyclase, and thus to a decrease in cAMP production

How to run a cAMP HTRF assay

Watch this video to learn about using a streamlined, no-wash, add-and-read HTRF® cAMP assay kit to monitor GPCR activation.


We guide you toward success

You’ll never be lost with our highly regarded cAMP Guides. Cisbio scientists have worked for many years with numerous Gαi- and Gαs-coupled GPCRs to produce a detailed set of recommendations, summarized in the guide. Thousands of GPCR researchers have already downloaded their copy of this valuable reference!

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Gq coupled receptors

IP-One, the best alternative to calcium flux assays

Cisbio’s platform includes IP-One, a very unique, non-isotopic assay and the best alternative to calcium flux assays. IP-One specifically measures IP-1 levels in cells. Over the past decade, IP-One has demonstrated its efficiency on numerous occasions for discovering and/or characterizing new compounds that target Gαq coupled GPCR. Discover the many benefits of IP-One by watching this short video.


Ready for more? All essential information on IP-One are now available in one convenient eBook. This document offers an in-depth focus on the very unique benefits of IP-One accumulation assay over Calcium Flux technologies.

Download IP-One gq siganling guide
Download IP-One gq guides

Never be at a loss with our acclaimed IP-One Guide. For years Cisbio’s scientists have worked with many Gαq coupled GPCR to produce a set of recommendations summarized in the guide. You’ll find all the guidance and support you need to get your experiment right the first time.