function:Calcium-regulated non-lysosomal thiol-protease which catalyzes limited proteolysis of substrates involved in cytoskeletal remodeling and signal transduction. This small subunit may act as a tissue-specific chaperone of the large subunit, possibly by helping it fold into its correct conformation for activity.,similarity:Contains 4 EF-hand domains.,subcellular location:Translocates to the plasma membrane upon calcium binding.,subunit:Heterodimer of a large (catalytic) and a small (regulatory) subunit.,