GPCR Assay Optimization with Chimeric G Proteins

GPCR assay optimization using chimeric G proteins enables improved signalling control and enhanced assay performance. At Sygnature Discovery, we engineer custom G protein constructs to redirect signalling through preferred pathways, increasing assay sensitivity and streamlining functional readouts across diverse GPCR targets. 

Introduction

Cell-based assays represent an important step in  understanding the functional effects of GPCR  modulation. Having access to high quality cellular tools is critical in driving forward these studies, providing reproducible data and clear insight when you need it most.  One of the major challenges faced when developing robust functional GPCR assays is defining the  optimal signalling components to ensure a reliable downstream assay and lead optimization. While some GPCRs signal amicably via endogenous host cell G proteins, other receptros benefit from  over-expression of a specific G protein to enable coupling and downstream signalling. Additionally, when developing assay systems for orphan receptors lack of information on the target’s signalling  mechanism can present a barrier to assay development and receptor de-orphanization.

This collaboration underscores the multifunctional nature of GDF15-GFRAL-RET, impacting pathways critical for cellular stress response and energy balance. Given its regulatory influence across broad physiological systems, this pathway presents new therapeutic opportunities, particularly in areas such as metabolic disorders and cancer.

Optimizing G Protein Coupling

Using a comprehensive panel of G protein constructs Sygnature Discovery’s assay development team quickly iden­tifyies optimal G proteins partners for your GPCR target, delivering robust functional assays for downstream drug discovery screening.

Figure 1. G protein profiling. Identification of optimal G protein coupling partners for detection of robust functional GPCR responses. A range of G-proteins were co-transfected with taregt receptor to dentify optimal partner for downstream cAMP quantitation assay.

Convenient Assays Delivered

GPCRs signal via a variety of pathways which may or may not be amenable of high throughput assay formats. Using chimeric G proteins, Sygnature Discovery’s assay development team can design robust assay to drive GPCR signalling via pathways and endpoint readouts suited to your preferred screening platforms, resulting in reliable, high-quality data for your drug discovery campaigns.

Figure 2. Gi-coupled GPCR targets driven to signal via Gq pathway using chimeric G proteins to enable high-throughput screening using calcium mobilization assays.