Send to

Choose Destination
Biochem Biophys Res Commun. 2000 Jun 7;272(2):472-6.

Properties and intracellular localization of calpain activator protein.

Author information

Department of Experimental Medicine-Biochemistry Section, University of Genoa, Italy.


In this paper, we have further analyzed the properties of calpain activator (CA) in order to better define its physiological function. The activator shows a pH optimum approximately 7.8-8.0, independently of the nature of the buffer used. Although the maximal activity is observed with human acid-denatured globin, the effect of CA is detectable with other protein substrates, such as casein and insulin. A comparable activating effect is observed also with the synthetic substrate Succ-Leu-Tyr-AMC. The activatory effect has been evaluated in a reconstructed system, using plasma membrane Ca(2+)-ATPase as substrate. CA is localized in erythrocyte precursor cells on the inner surface of the plasma membrane in very high amount and its level profoundly decreases up to 10% of the original value when cells reach the terminal differentiated state.

[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center