Homogeneous Fluorescence-based Assay for Detecting Intracellular Calcium Mobilisation

Calcium signaling is a key event in many physiological processes, but has also been linked to pathways that are important in cancer, much as migration, invasion, proliferation and apoptosis.  The role of calcium as a regulator of these processes combined with the altered expression of specific isoforms of calcium pumps and channels in some cancers has created significant interest in these proteins as novel targets for cancer drug discovery.

Calcium flux assays are preferred methods in drug discovery for screening G protein coupled receptors (GPCR). The Screen Quest™ Calcium Assay Kit from amsbio provides a homogeneous fluorescence-based assay for detecting the intracellular calcium mobilisation. Cells expressing a GPCR of interest that signals through calcium are pre-loaded with a fluorogenic cell-permeable calcium indicator which can cross cell membrane. Once inside the cell, the lipophilic blocking groups are cleaved by non-specific cell esterase, resulting in a negatively charged fluorescein dye that stays inside cells, and its fluorescence is greatly enhanced upon binding to calcium. When cells stimulated with screening compounds, the receptor signals release of intracellular calcium, which greatly increase the fluorescence of the calcium indicator.

The Screen Quest Calcium Assay Kit provides an optimised assay method for monitoring G-protein-coupled receptors (GPCRs) and calcium channels. The assay can be performed in a convenient 96-well or 384-well microplate format and easily adapted to automation.