Members of the G protein coupled receptor (GPCR) family play key roles in many physiological functions and have been extensively exploited pharmacologically to treat diseases. Individual GPCRs exert diverse and distinct effects on cellular physiology and transduce signals by activating heterotrimeric G proteins. Mammalian genomes encode 16 different G protein alpha subunits, and each one of them has distinct properties. Here, we developed a single-platform, optical strategy for the direct monitoring of G protein activation in live cells, and using it we profiled the activities of individual GPCRs across a range of different G proteins, simultaneously quantifying both magnitude of their signaling and activation rates. We report that GPCRs engage multiple G proteins with varying efficacy and kinetics, generating fingerprint-like profiles that define individual receptors. We found that different classes of GPCR ligands, including full and partial agonists, allosteric modulators, and antagonists distinctly affected these fingerprints to functionally bias GPCR signaling. Finally, we showed that intracellular signaling modulators further altered the G protein–coupling profiles of GPCRs, which suggests that their differential expression may alter signaling outcomes in a cell-specific manner. . These observations suggest that the diversity of the effects of GPCRs on cellular physiology may be determined by their differential engagement of multiple G proteins with varying signal magnitudes and activation kinetics, properties that may be exploited pharmacologically.

Stress can be a motivational force for decisive action and adapting to novel environment; whereas, exposure to chronic stress contributes to the development of depression and anxiety. However, the molecular mechanisms underlying stress-responsive behaviors are not fully understood. Here, we identified the orphan receptor GPR158 as a novel regulator operating in the prefrontal cortex (PFC) that links chronic stress to depression. GPR158 is highly upregulated in the PFC of human subjects with major depressive disorder. Exposure of mice to chronic stress also increased GPR158 protein levels in the PFC in a glucocorticoid-dependent manner. Viral overexpression of GPR158 in the PFC induced depressive-like behaviors. In contrast GPR158 ablation, led to a prominent antidepressant-like phenotype and stress resiliency. We found that GPR158 exerts its effects via modulating synaptic strength altering AMPA receptor activity. Taken together, our findings identify a new player in mood regulation and introduce a pharmacological target for managing depression.

Members of the R7 family of the regulators of G-protein signaling (R7 RGS)

The Concise Guide to PHARMACOLOGY 2021/22 is the fifth in this series of biennial publications. The Concise Guide provides concise overviews, mostly in tabular format, of the key properties of nearly 1900 human drug targets with an emphasis on selective pharmacology (where available), plus links to the open access knowledgebase source of drug targets and their ligands (https://www.guidetopharmacology.org), which provides more detailed views of target and ligand properties. Although the Concise Guide constitutes over 500 pages, the material presented is substantially reduced compared to information and links presented on the website. It provides a permanent, citable, point‐in‐time record that will survive database updates. The full contents of this section can be found at http://onlinelibrary.wiley.com/doi/bph.15537. In addition to this overview, in which are identified ‘Other protein targets’ which fall outside of the subsequent categorisation, there are six areas of focus: G protein‐coupled receptors, ion channels, nuclear hormone receptors, catalytic receptors, enzymes and transporters. These are presented with nomenclature guidance and summary information on the best available pharmacological tools, alongside key references and suggestions for further reading. The landscape format of the Concise Guide is designed to facilitate comparison of related targets from material contemporary to mid‐2021, and supersedes data presented in the 2019/20, 2017/18, 2015/16 and 2013/14 Concise Guides and previous Guides to Receptors and Channels. It is produced in close conjunction with the Nomenclature and Standards Committee of the International Union of Basic and Clinical Pharmacology (NC‐IUPHAR), therefore, providing official IUPHAR classification and nomenclature for human drug targets, where appropriate.

The type 5 G protein β subunit (Gβ5) can form complexes with members of the Regulator of G protein Signaling 7 (RGS7) family, but the relevance to neuronal G protein signaling is unclear. We report that mouse RGS7/Gβ5 complexes bind to G protein–gated potassium channels and facilitate their functional coupling to GABAB receptors in neurons. These findings identify a novel compartmentalization mechanism critical for ensuring high temporal resolution of neuronal G protein signaling.