NuPath, a brighter TRUPATH-derived BRET sensor, exposes subtle and constitutive GPCR G protein activity
- NuPath retains the TRUPATH sensor layout but swaps the luciferase donor for NanoLuc and the acceptor for eYFP, and works in standard 96-well plates without a transfer step.
- Matched comparisons across six GPCRs and several G protein subtypes showed much larger agonist responses for most Gα sensors, while the GαOA sensor gave similar signal with less variability.
- The wider dynamic range revealed receptor-specific Gβγ pairing preferences that TRUPATH largely missed, and it detected inverse agonists dampening constitutive signalling at the growth hormone secretagogue receptor.
💡 Points Based on the abstract
A brighter sensor is only as good as its pharmacology. Before I trust the new Gβγ pairing preferences, I want them checked against orthogonal readouts, because overexpressed, tagged subunits can manufacture selectivity. The inverse-agonist detection at the ghrelin receptor is the more useful result: constitutive activity is where TRUPATH went blind, and it matters for screening.