AVERNA , Monica

We here describe the purification of calpastatin from human erythrocytes. When calpastatin is purified from tissues, it is necessary to measure its inhibitory activity against calpain in the presence of Ca2+ to specifically identify the protein. Thus, the purification steps necessary to obtain the inhibitor protein were originally designed to...

Immunoblotting is a procedure routinely used to analyze calpastatin expression. However, immunoblotting alone may not be adequate for this task, since calpastatin isoforms can vary by tissue, can be modified by partial digestion, and can undergo posttranslational modifications. Here we describe a method for more precise evaluation of...

The production of recombinant calpastatin in E. coli has become an efficient tool to obtain discrete amounts of a specific calpastatin species that can be present concomitantly with other calpastatin fragments/forms in the same tissue or cell type in a given condition. Indeed, at present, it is still difficult to distinguish the various...