Unexpected role of the L-domain of calpastatin during the autoproteolytic activation of human erythrocyte calpain

  title={Unexpected role of the L-domain of calpastatin during the autoproteolytic activation of human erythrocyte calpain},
  author={Roberta De Tullio and Alice Franchi and Antonino Martines and Monica Averna and Marco Pedrazzi and Edon Melloni and Bianca Sparatore},
  journal={Bioscience Reports},
Autoproteolysis of human erythrocyte calpain-1 proceeds in vitro at high [Ca2+], through the conversion of the 80-kDa catalytic subunit into a 75-kDa activated enzyme that requires lower [Ca2+] for catalysis. Importantly, here we detect a similar 75 kDa calpain-1 form also in vivo, in human meningiomas. Although calpastatin is so far considered the specific inhibitor of calpains, we have previously identified in rat brain a calpastatin transcript truncated at the end of the L-domain (cast110, L… 
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