Use

Calpain proteinases are defined currently as papain-like neutral proteases that are calcium activated. Calpains 1 and 2 are composed of a large subunit, which is proteolytically active, and a small subunit (also called calpain-4), or enhancer protein, that is not proteolytically active. A second small subunit, Calpain Small-2, has been identified. When coexpressed with calpain large subunits, calpain small-2 helps fold the large subunit, but does not stay associated, acting like a chaparonin. Other calpain proteins identified to date (calpain 5, 6, 8, 9, 10, 11, 12, 13, 14, 15) are not thought to require small subunit-1 for activation, but little is known about the newer small subunits. Domains in the large subunit include the amino terminal domain-I, the proteinase domain-II, domain-III, and the EF-hand domain-IV (Domain-T in calpains 5 & 6, Domain-N for calpain-7). Calpain-7 domain-N does not have the standard calpain EF hand domain for binding calcium, making it unclear whether it is calcium regulated. In place of the EF hand calcium-binding domain IV, Calpain-7 has a sequence most closely resembling Domain-III, with unknown function. Calpain-7 is widely distributed, found in most tissues analyzed. RP4Calpain-7 recognizes latent and amino-processed Calpain-7; the latent large subunit is 93 Kd, and the amino terminal truncation at activation yields an approximately 58 Kd form. Cleavage of the carboxyterminal region generates smaller forms of Calpain-7, but it is not clear if these forms are proteolytically active. RP4Calpain-7 works well for Western Blotting applications, and when used against the reduced protein identifies bands at 93 Kd, 68 Kd, and a series of further cleaved forms. Rat, mouse and human Calpain-7 are detected with RP4Calpain-7. A recommended starting concentration for Western blots is 1:1000 when using colorimetric substrates such as BCIP/NBT, and 1:5000 for chemiluminescent substrates. Higher concentrations of antibody may be needed for samples from more distantly related species

FOR RESEARCH USE ONLY. NOT FOR USE IN HUMANS.

Triple Point Biologics products are sold exclusively through Abcam. For availability, pricing and buying information please select your country below and press 'Go'. You will be relocated to the relevant datasheet page on Abcam's website.