Caspase-6 Colorimetric Assay Kit provides a simple procedure for assaying the activity of caspases that recognize the sequence VEID. Consequently, the user can detect the chromophore p-nitroanilide (pNA), after cleavage from the labeled substrate VEID-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-6 activity.
There are two classes of caspases that involve in apoptosis; initiators (activation by receptor cluster) and effectors (activation by mitochondrial permeability transition). Proapoptotic signals autocatalytically activate initiator caspases, such as Caspase 8 and Caspase 9. As a consequence, activated initiator caspases then process effector caspases, such as Caspase 3 and Caspase 7, which in turn cause cell collapse. As a resume, 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.