The classification, characters and maturation methods of VPEs were sum- marized, and its regulation function to vacuolar was also analyzed. Furthermore, effects of the enzyme in vacuolar-mediated plant defense mechanism were discussed to point out that VPEs were divided into 3 subfamilies via autocatalytic mature including seed-type VPE, vegetative-type VPE and new-type VPE. Especially, seed- type VPE mediated the process of storage protein, while vegetative-type VPE and new-type VPE regulated and controlled programmed death of plant cells.
