G Protein Dependent Functional Assays

G Protein Dependent Functional Assays

For Research Use Only. Not For Clinical Use.

Creative Biolabs provides G protein dependent functional assay services based on multiple assay formats to accelerate GPCR research and drug development. We can further help speed up your drug discovery by combining high-throughput technology.

Importance of G Protein Dependent Functional Assays

G proteins, also known as guanine nucleotide-binding proteins, typically exist in either an active GTP-bound state or an inactive GDP-bound state. G protein-coupled receptors (GPCRs), one of the most successful therapeutic targets, can activate heterotrimeric G proteins to elicit cellular responses. GPCR-G protein interactions are involved in signal transduction cascades and the modulation of downstream effector events.

Binding assays are helpful to identify new compounds targeting GPCRs. G protein dependent functional assays are essential for further analysis of G protein activation and G protein-mediated biological events, which can help to fully describe the overall characteristics of these compounds and provide useful information on the selection of candidate compounds.

The guanine nucleotide cycle of heterotrimeric G-proteins.Figure 1. The guanine nucleotide cycle of heterotrimeric G-proteins. (Johnston C A & Siderovski D P, 2007)

G Protein Dependent Functional Assay Services

We offer our customers with a comprehensive selection of G protein dependent functional assays to meet their different research needs.

Assays Suitable GPCRs Description
GTPγS binding assay Gαi/o
  • Directly measuring the guanine nucleotide exchange of G proteins, an early event after GPCR activation.
  • Full agonists, partial agonists, neutral antagonists, inverse agonists, and allosteric regulators can be discriminated.
cAMP assay Gαs, Gαi/o
  • Useful tool for elucidating novel functions of orphan GPCRs and understanding physiological implications.
  • Applicable to drug screening for GPCRs.
IP3/IP1 assay Gαq
  • Assessing the activity of phospholipase C (PLC), which can be activated by the stimulation of Gaq or Gai coupled-GPCRs.
  • Applicable to living cells.
Ca2+ assay Gαq
  • Measuring intracellular Ca2+.
  • A popular tool for in GPCR screening.
  • Applicable to living cells.
Reporter assay Any GPCRs
  • Provide an easy way to measure the activation of a specific signaling cascade of interests.
  • Provide a simple high throughput method for screening GPCR targets linked to second messenger pathways.

Our Advantages

  • Customized services based on multiple assays formats.
  • One-stop solutions for all your problems.
  • High-quality and reliable results under strict quality control conditions.
  • Fast turnaround time and competitive price.

Creative Biolabs provides our customers with customized G protein dependent functional assay services in a time- and cost-effective manner. Our experts will work closely with you to fully meet your requirements.

If you are interested in our services or have any specific needs, please feel free to contact us for more details.


  1. ohnston C A & Siderovski D P. Receptor-mediated activation of heterotrimeric G-proteins: current structural insights. Molecular pharmacology, 2007, 72(2): 219-230.
  2. Mahoney J P & Sunahara R K. Mechanistic insights into GPCR–G protein interactions. Current opinion in structural biology, 2016, 41: 247-254.