Description
Test Principle: This assay employs a two-site sandwich ELISA to quantitate CASP9 in samples. An antibody specific for CASP9 has been pre-coated onto a microplate. Standards and samples are pipetted into the wells and any CASP9 present is bound by the immobilized antibody. After removing any unbound substances, a biotin-conjugated antibody specific for CASP9 is added to the wells. After washing, Streptavidin conjugated Horseradish Peroxidase (HRP) is added to the wells. Following a wash to remove any unbound avidin-enzyme reagent, a substrate solution is added to the wells and color develops in proportion to the amount of CASP9 bound in the initial step. The color development is stopped and the intensity of the color is measured.
Overview: The aspartic acid specific protease caspase-9 has been linked to the mitochondrial death pathway. It is activated during programmed cell death (apoptosis). Induction of stress signalling pathways JNK/SAPK causes release of cytochrome c from mitochondria and activation of apaf-1 (apoptosome), which in turn cleaves the pro-enzyme of caspase-9 into the active form. Caspase-9 is a member of the cysteine-aspartic acid protease (caspase) family. This protein is processed by caspase APAF1; this step is thought to be one of the earliest in the caspase activation cascade. Alternative splicing results in two transcript variants which encode different isoforms