Recombinant luciferase from firefly (Photinus pyralis) or Renilla (Renilla reniformis, Sea pansy) catalyse ATP-dependent cleavage of luciferin and promote generation of bioluminescence. Luminescence-based reporters are used to quantify cell viability or target gene expression.
For measuring cell viability the intracellular ATP level is used as indicator. The CellTiter-Glo® Luminescent Cell Viability Assay is a homogeneous method of determining the number of viable cells in culture based on quantitation of the ATP present, which signals the presence of metabolically active cells. The CellTiter-Glo® Assay is designed for use with multiwell plate formats making it ideal for automated high-throughput screening (HTS), cell proliferation and cytotoxicity assays.
Target gene expression / Pathway activity
When applied to measure taget gene expression, luciferase, fused to the promotor of the target gene, is transiently or stabely transfected into cells. Usually, the intensity of emitted luminescence light is measured on single well basis by plate readers upon cell-lysis and addition of luciferin (see protocols section).