Major secreted protease of mast cells with suspected roles in vasoactive peptide generation, extracellular matrix degradation, and regulation of gland secretion. Preferential cleavage: Phe-|-Xaa > Tyr-|-Xaa > Trp-|-Xaa > Leu-|-Xaa. Secretory granules. Mast cells. Belongs to the peptidase S1 family. Granzyme subfamily.