Technical Data
Calpastatin, Domain IV
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. Calpastatin, a specific endogenous inhibitor of calpain, has a predicted molecular weight of ~77kD and an internal repeat of four homologous domains which allow it to inhibit multiple calpain molecules simultaneously. It functions by binding to calpain when calpain binds calcium. When calpastatin is subjected to proteolytic digestion, fragments of calpastatin as small as 15kD still retain inhibitory activity.

Cellular Localization: Cytoplasmic and Nuclear

Suitable for use in Western Blot and Immunocytochemistry. Other applications not tested.

Recommended Dilution:
Optimal dilutions to be determined by the researcher.

Storage and Stability:
May be stored at 4C for short-term only. For long-term storage and to avoid repeated freezing and thawing, aliquot Store at -20C. Aliquots are stable for at least 12 months at -20C. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap. Further dilutions can be made in assay buffer.
100ul-20CBlue IceBovineMouse
Not determined
Purified bovine skeletal muscle 80 kDa subunit of m-Calpastatin. Epitope: This antibody recognizes an epitope between amino acid residues 543-673 (domain IV) of human calpastatin.
0.05% Sodium Azide; Raw Ascites
This antibody does not crossreact with calpains or calmodulin. Species Crossreactivity: Crossreacts with bovine, human, porcine and rat. Not yet tested in other species.
Intended for research use only. Not for use in human, therapeutic, or diagnostic applications.
Boehm ML et al. Changes in the calpains and calpastatin during postmortem storage of bovine muscle. J Anim Sci 76:2415-34 (1998). Cong J et al. Effect of monoclonal antibodies specific for the 28-kDa subunit on catalytic properties of the calpains. J Biol Chem 268:25740-7 (1993). Lane RD et al. A comparison of the intracellular distribution of mu-calpain, m-calpain, and calpastatin in proliferating human A431 cells. Exp Cell Res 203:5-16 (1992).