Immunofluorescent analysis of Mu-Calpain in MCF-7 Cells. Cells were grown on chamber slides and fixed with formaldehyde prior to staining. Cells were probed without (control) or with a Mu-Calpain monoclonal antibody (Product # MA3-941) at a dilution of 1:20 overnight at 4 C, washed with PBS and incubated with a DyLight-488 conjugated secondary antibody (Product # 35503). Mu-Calpain staining (green), F-Actin staining with Phalloidin (red) and nuclei with DAPI (blue) is shown. Images were taken at 60X magnification.
|Tested species reactivity||Bovine, Human, Pig, Rat|
|Published species reactivity||Bovine|
|Host / Isotype||Mouse / IgG1|
|Immunogen||Purified bovine skeletal muscle 80 kDa mu-calpain subunit.|
|Contains||0.05% sodium azide|
|Storage Conditions||-20° C, Avoid Freeze/Thaw Cycles|
|Tested Applications||Dilution *|
|Western Blot (WB)||1:1,000|
* Suggested working dilutions are given as a guide only. It is recommended that the user titrate the product for use in their own experiment using appropriate negative and positive controls.
|Western Blot (WB)||See 1 publications below|
MA3-941 detects mu-calpain from human platelets and erythrocytes, bovine platelets, heart and skeletal muscle, rat myoblasts, kidney, liver and spleen, and pig cultured cells. This antibody does not cross-react with m-calpain, n-calpain, calmodulin or calpastatin.
MA3-941 has been successfully used in Western blot, IF and immunocytochemistry procedures. By Western blot, this antibody detects an ~80 kDa protein representing mu-calpain from human platelets and erythrocytes. Immunocytochemical staining of mu-calpain in porcine LLC-PK1 cells with MA3-941 results in diffuse cytoplasmic staining. This product has not been shown to be effective in immunoprecipitation experiments.
The MA3-941 antigen is purified bovine skeletal muscle 80 kDa mu-calpain subunit. This antibody recognizes an epitope between amino acids 245-265 (domain II) of human mu-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-Calpain, also known as Calpain-I, and m-calpain, also known as Calpain-II, are intracellular, calcium-dependent cysteine proteases.
Mu- and m-calpains are heterodimers consisting of 28 kDa and 80 kDa subunits. The 28 kDa subunit is identical in the two isoforms, but the 80 kDa subunits differ with ~50% sequence similarity. 28 kDa/80 kDa complexes are thought to be inactive proenzymes which, upon binding of calcium, undergo conformational changes that promotes cleavage of the 28 kDa subunit and results in enzyme activation.
For Research Use Only. Not for use in diagnostic procedures. Not for resale without express authorization.
Effect of monoclonal antibodies specific for the 28-kDa subunit on catalytic properties of the calpains.
MA3-941 was used in western blot to study the effect of specific calpain antibodies for the regulation of calpain function
|Cong J,Thompson VF,Goll DE||The Journal of biological chemistry (268:25740)||1993|