Calcium-Sensitive Proteases

Calpain and cathepsin are calcium-sensitive proteases. Calpains are a family of 14 cysteine proteases that are involved in a range of cellular processes. These include remodeling of cytoskeletal attachments to the plasma membrane during cell fusion and cell motility, proteolytic modification of molecules in signal transduction pathways, degradation of enzymes controling progression through the cell cycle, regulation of gene expression, substrate degradation in some apoptotic pathways, and an involvement in long-term potentiation.

Cathepsins are lysosomal calcium-sensitive proteases that have a key role in cellular protein turnover. This group of proteases includes serine proteases (cathepsins A and G), aspartic proteases (cathepsin D and E) and cysteine proteases (cathepsins B, C, F, H, K, L, O, S, W and Z). The main function of cathepsins is protein recycling within the lysosome but they are also known to be involved in a range of other physiological, as well as pathological processes. These include maturation of the MHC class II complex, bone remodeling, keratinocyte differentiation, tumor progression and metastasis, osteo- and rheumatoid arthritis, and atherosclerosis.

Calcium Sensitive Protease Gene Data