Calpain 1 (Calcium-activated neutral protease, Calcium-activated neutral proteinase 1, Calpain 1 large subunit, CANP, CANP I, CANP1, Capa-1, Capa1, Capn1,mu-Calpain, muCANP, muCL, u-Calpain)

The calpain (calcium-dependent protease or calcium-activated neutral protease) system consists of two ubiquitous forms of calpain (mu-calpain and m-calpain), a tissue specific calpain (n-calpain), and a calpain inhibitory protein (calpastatin). The calpain system has been detected in every vertebrate tissue examined, and has been suggested to play a regulatory role in cellular protein metabolism. This regulatory role may have important implications in platelet aggregation and pathologies associated with altered calcium homeostasis and protein metabolism such as ischemic cell injury and degenerative diseases. Inhibitors of calpain have been shown to block dexamethasone and low level irradiation induced apoptosis in thymocytes suggesting that calpain has a regulatory or mechanistic role in apoptotic cell death.Mu and M Calpains are heterodimers consisting of 28kD and 80kD subunits. The 28kD subunit is identical in the two isoforms, but the 80kD subunits differ with ~50% sequence similarity. 28kD / 80kD complexes are thought to be inactive proenzymes which, upon binding of calcium, undergo conformational changes that promotes cleavage of the 28kD subunit and results in enzyme activation. Applications: Suitable for use in ELISA, Western Blot, Flow Cytometry, Immunocytochemistry and Immunohistochemistry. Other applications not tested. Recommended Dilution: Immunohistochemistry (frozen): 1:50 Western Blot: 1:500 detects a band at ~80kD representing M Calpain in bovine platelets Flow Cytometry: 1:50 Immunocytochemistry: staining of M Calpain in LLC-PK1 cells results in diffuse cytoplasmic pattern Optimal dilutions to be determined by the researcher. Storage and Stability: May be stored at 4 degrees C for short-term only. Aliquot to avoid repeated freezing and thawing. Store at -20 degrees C. Aliquots are stable for at least 12 months. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap.