Caspases are a family of protease enzymes that play essential roles in programmed cell death. Caspase activity is measured by a short peptide containing specific cleavage sequences that are recognized by the caspase and are covalently attached to a colorimetric or fluorogenic detection probe. Initiator caspases (caspase 2, 8, 9 and 10) initiate the apoptosis signal and the executioner caspases (caspase 3, 6, and 7) carry out the mass proteolysis that leads to apoptosis.
Caspase-2 Colorimetric Assay Kit provides a simple procedure for assaying the activity of caspases that recognize the sequence VDVAD. Consequently, the chromophore p-nitroanilide (pNA) can be detected, after cleavage from the labeled substrate VDVAD-AFC. The pNA can be quantified using a spectrophotometer or a microplate reader at 405 nm. Comparison of pNA absorbance from an apoptotic sample vs pNA absorbance of control allows determination of the fold increase in caspase-2 activity.