G-protein-coupled receptor-mediated MAPK and PI3-kinase signaling is maintained in Chinese hamster ovary cells after γ-irradiation.

To expedite G-protein-coupled receptor (GPCR) drug screening studies, cell lines amenable to transfection (e.g. CHO cells) have been widely used as cellular models.

An emerging role for kinase screening in GPCR drug discovery.

GPCRs are a large class of cell-surface receptors that are involved in a diverse array of biological processes, including many that are critical to diseases. As a result, GPCRs are a major focus for drug discovery research, and have been highly amenable to therapeutic intervention. However, the successes to date may represent the 'low-hanging fruit' (ie, outcomes that have been easiest to achieve).

Aequorin-based functional assays for G-protein-coupled receptors, ion channels, and tyrosine kinase receptors.

Aequorin is a photoprotein originating from jellyfish, whose luminescent activity is dependent on the concentration of calcium ions. Due to the high sensitivity and low background linked to luminescent assays, as well as to its absence of toxicity and its large linear dynamic range, aequorin has been used as an intracellular calcium indicator since its discovery in the early 1960s. The first applications of aequorin involved its microinjection in cells.

Adaptation of aequorin functional assay to high throughput screening.

AequoScreen, a cellular aequorin-based functional assay, has been optimized for luminescent high-throughput screening (HTS) of G protein-coupled receptor (GPCRs). AequoScreen is a homogeneous assay in which the cells are loaded with the apoaequorin cofactor coelenterazine, diluted in assay buffer, and injected into plates containing the samples to be tested. A flash of light is emitted following the calcium increase resulting from the activation of the GPCR by the sample.