Succinate receptor 1 signaling mutually depends on subcellular localization and cellular metabolism.

Succinate is a pivotal tricarboxylic acid cycle metabolite but also specifically activates the G- and G-coupled succinate receptor 1 (SUCNR1). Contradictory roles of succinate and succinate-SUCNR1 signaling include reports about its anti- or pro-inflammatory effects. The link between cellular metabolism and localization-dependent SUCNR1 signaling qualifies as a potential cause for the reported conflicts.

Integrated NMR-crystallography-computational approach for molecular recognition studies of human Gαi3 protein by a small molecule inhibitor.

The small molecule IGGi-11 targets Gαi subunits of heterotrimeric guanine nucleotide-binding proteins. Gα subunits are activated by G-protein-coupled receptors in response to extracellular stimuli by accelerating the exchange of GDP for GTP, but they are also activated by intracellular proteins like GIV, of which elevated levels correlate with increased cell migration and cancer metastasis. IGGi-11 disrupts the interaction of Gαi proteins with GIV and inhibits pro-invasive traits of metastatic breast cancer cells without interfering with GPCR signaling.

Protocol to investigate G protein-coupled receptor signaling kinetics and concentration-dependent responses using ONE-GO biosensors.

ONE vector G protein optical (ONE-GO) biosensors are versatile tools to measure the activity of G protein-coupled receptors (GPCRs) in cells. The availability of ONE-GO biosensors for ten active Gα subunits representative of all four G protein families (G, G, G, and G) permits the study of virtually any GPCR. Here, we present a protocol to implement ONE-GO biosensors in cell lines to investigate GPCR signaling kinetics and concentration-dependent responses.

Protocol for detecting endogenous GPCR activity in primary cell cultures using ONE-GO biosensors.

ONE vector G protein Optical (ONE-GO) biosensors can measure the activity of endogenously expressed G protein-coupled receptors (GPCRs) in primary cells. By detecting G proteins that belong to all four families (G, G, G, G) across cell types, these biosensors provide high experimental versatility. We first describe steps to express ONE-GO biosensors in primary cells using lentiviral transduction.

Direct detection of endogenous Gαi activity in cells with a sensitive conformational biosensor.

Activation of heterotrimeric G-proteins (Gαβγ) by G-protein-coupled receptors (GPCRs) is not only a mechanism broadly used by eukaryotes to transduce signals across the plasma membrane, but also the target for a large fraction of clinical drugs. However, approaches typically used to assess this signaling mechanism by directly measuring G-protein activity, like optical biosensors, suffer from limitations. On one hand, many of these biosensors require expression of exogenous GPCRs and/or G-proteins, compromising readout fidelity.