TABLE 2.
Suggested terms to define the pathway processes at different levels being compared for bias
| Term | Examples of assay principles |
|---|---|
| Accumulation | Ca2+ or cAMP accumulation |
| Binding/coupling | Proximity |
| Activation | Receptor conformation and G protein activation, for example, GTPase activity, GTPγS binding, or recruitment of downstream effectors. |
| Dissociation | G protein dissociation/rearrangement |
| Phosphorylation | Incorporation of 32P in a specific protein. Two‐dimensional phosphopeptide mapping after orthophosphate labelling, MS‐based identification of phosphorylation sites, Phosphosite‐specific antibody assays or arrays |
| Recruitment | Subcellular redistribution |
| Signalling | Downstream cellular second messenger levels |
| Internalization | ELISA, flow cytometry, diffusion‐enhanced resonance energy transfer (DERET), enhanced bystander BRET (ebBRET), (confocal) microscopy, antibody‐feeding experiments, real‐time internalization by SNAP‐tagged receptors |
| Tissue phenotype | Blood vessel contraction, cell migration, hormone secretion, heart rate, force of contraction, glandular secretion. |
| Transcription | Differential gene arrays after agonism, qPCR, and gene reporter assay. |