Metalloprotease. Binds 1 zinc ion per subunit. Nematocyte and pharyngeal gland. Expressed in the early planula stage of Nematostella in single cells of the ectoderm. These cells are thin and elongated as would be expected of developing nematocytes. In the later stages, the expression expands to an additional domain of large thick cells in the pharynx. The size and richness of vesicles suggest that these cells are not nematocytes but gland cells, and in the polyp stage, they become the major expression domain of this protein.