Cathepsin D Inhibitor Screening Kit (Fluorometric)

Apoptosis is often mediated by the traditional caspase-mediated cleavage cascade. In addition, alternative proteolytic enzymes such as the lysosomal cathepsin proteases can also initiate or propagate proapoptotic signals. Cathepsins are lysosomal proteases that play an important role in mammalian cellular turnover such as bone resorption. Cathepsins are often used as sensitive markers in a variety of toxicological investigations. Cathepsin D is a lysosomal aspartyl protease belonging to the peptidase A1 family and is used as a marker of breast cancer tumor.

 The Cathepsin D Inhibitor Screening Kit (Fluorometric) provides a simple, fast and convenient way for screening of cathepsin D inhibitors based on fluorometric method. The assay utilizes the preferred cathepsin-D substrate sequence GKPILFFRLK(Dnp)-D-R-NH2 labeled with MCA. While cleavage of the synthetic substrate by cathepsin-D, the released fluorescence (Ex/Em = 328/460 nm) can be easily quantified using a fluorecence microtiter plate reader or a fluorometer. The relative efficacy of the test inhibitor is compared to the positive control inhibitor Pepstatin A (IC50 <0.1 nM). The kit is suitable for high throughput screening (HTS) and can be assayed in 96-well plate.