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Updated: Aug 23, 2026

A Kinetic Fluorescence-based Ca2+ Mobilization Assay to Identify G Protein-coupled Receptor Agonists, Antagonists, and Allosteric Modulators
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Translating G protein subunit diversity into functional specificity

Janet D Robishaw1, Catherine H Berlot

  • 1100 N. Academy Ave, Weis Center for Research, Geisinger Clinic, Danville, PA 17822-2614, USA. jrobishaw@geisinger.edu

Current Opinion in Cell Biology
|June 16, 2004
PubMed

Historically, it has been assumed that the functional roles of G proteins in receptor recognition and effector regulation are specified by their diverse alpha subunits. However, the discovery of similarly diverse betagamma subunits that participate in both of these functional processes has called this assumption into question; recent work suggests that G proteins function as heterotrimers whose roles in particular receptor signaling pathways are determined by their specific alphabetagamma subunit combinations. Although much remains to be learned, the assembly of specific alphabetagamma subunit combinations seems to involve both structural and spatial factors.

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