Calcium-regulated non-lysosomal thiol-protease. Involved in the organization of the actin-related cytoskeleton during embryogenesis. Activated by millimolar concentrations of calcium, and by phosphatidylinositol 4,5-diphosphate, phosphatidylinositol 4-monophosphate, phosphatidylinositol and phosphatidic acid. Additional isoforms seem to exist. Localized to the anterior and posterior embryonic poles just after fertilization. Becomes distributed around the polar buds and just below the pole cells of the posterior pole during cleavage cycles. During these nuclear divisions anterior localization disappears. Localized to actin caps that underlie the plasma membrane, immediately above each nucleus at cleavage cycles 8 and 9. Localized to a small set of nerve, midgut and blood cells in adults. Undergoes calcium-dependent autolytic cleavage between Lys-54 and Asn-55, which is necessary for activation of the protein. This protein binds calcium. Belongs to the peptidase C2 family.