Cathepsin D is a normal lysosomal protease that is expressed in all cells. It is an aspartyl protease with a pH optimum in the range of 3-5，and contains two N-linked oligosaccharides. Cathepsin D is synthesized as an inactive 52 kDa pro-enzyme. Activation involves the proteolytic removal of the 43 amino acid profragment and an internal cleavage to generate the two-chain form made up of 34 and 14 kDa subunits. Cathepsin D contains the mannose-6-phosphate lysosomal localization signal that targets the enzyme to the lysosomal compartment where it functions in the normal degradation of proteins. In certain tumor cells，Cathepsin D is abnormally processed and is secreted in its 52 kDa precursor form. Numerous clinical studies as well as in vitro evidence suggest that cathepsin D plays an important role in malignant transformation and may be a useful prognostic indicator for breast cancer.
应用类型
Western blot analysis （0.5-4 ug/ml） and in immunoprecipitation. However， the optimal conditions should be determined individually. The purified antibody detects both the 52 kDa proform and the 34 kDa cleaved fragment of Cathepsin D.
免疫原
Synthetic peptide surrounding amino acid 140 of mouse cathepsins D
