Metalloendoprotease which cleaves peptides at the amino side of hydrophobic residues - such as the hormones Akh and Dh31, and the neuropeptides Allatostatins (AST1, AST2, AST3 and AST4), Crz, Drosulfakinins (DSK-I and DSK-II), Lk, sNPF and the tachykinin peptides TK-1, TK-2, TK-4 and TK-5 (PubMed:27919317). Functions in female fertility, memory formation and may also act in regulating insulin signaling and food intake (PubMed:24395329, PubMed:27629706). Likely to be involved in controlling feeding behavior and the expression of insulin-like peptides by cleaving various regulatory peptides that include certain Drosulfakinins, Allatostatins and tachykinin peptides (PubMed:27919317). Required in females for normal patterns of egg laying and hatching (PubMed:24395329). Required in the dorsal paired medial neurons for the proper formation of long-term (LTM) and middle-term memories (MTM) (PubMed:27629706). Also required in the mushroom body neurons where it functions redundantly with neprilysins Nep2 and Nep3, in normal LTM formation (PubMed:27629706). Cleaves angiotensin-1 and tachykinin neuropeptide substance P (PubMed:19880729). Functions in maintaining muscle integrity, possibly independently of its endopeptidase activity (PubMed:22583317). Preferential cleavage of polypeptides between hydrophobic residues, particularly with Phe or Tyr at P1'. Binds 1 zinc ion per subunit. Optimum pH is 7. Interacts (via intracellular domain) with the putative carbohydrate kinase CG3534. In larval muscles, localizes to both the cell surface and sarcoplasmic reticulum membranes that are continuous with the nuclear membrane. Expressed in the gonads and testes of adults, and the adult and larval brain (at protein level) (PubMed:19880729). In embryos, expressed in the pericardial, muscle founder and glia cells (at protein level) (PubMed:19880729). In stage 12 embryos, expressed in specific dorsal muscle founder cells such as DA1 and DO2, and also in the certain pericardial progenitor cells where expression persists throughout embryogenesis (PubMed:19880729, PubMed:24395329). Expressed in the glia cells of the embryonic, larval and adult central nervous system (PubMed:19880729, PubMed:24395329). Expressed in the somatic muscles of larvae, pupae and adults (PubMed:22583317). Isoform A: Detected in the male abdomen (at protein level) (PubMed:19880729). Isoform B: Not detected in the male or female abdomen (at protein level) (PubMed:19880729). Expressed throughout development and in adults (at protein level). Isoform A: Highly expressed in adults and low levels of expression in larvae and pupae (at protein level). Isoform B: High levels of expression in larvae (at protein level), and low levels of expression in embryos (4-24 hr after oviposition), pupae and adults (at protein level). RNAi-mediated knockdown females lay fewer eggs and display a reduced hatch rate when mated to wild-type males (PubMed:24395329). Wild-type females mated to males that undergo RNAi-mediated knockdown, lay the same number of eggs and have a similar hatch rate to those mated to wild-type males (PubMed:24395329). RNAi-mediated knockdown in the dorsal paired medial neurons impairs middle-term (MTM) and long-term memory (LTM), but has no effect on normal aversion learning and anesthesia-resistant memory (ARM) (PubMed:27629706). RNAi-mediated knockdown in all mushroom body neurons has no effect on learning, ARM and LTM (PubMed:27629706). However, simultaneous knockdown with Nep3 does impair LTM, and simultaneous knockdown with both Nep2 and Nep3 results in a further reduction in LTM formation (PubMed:27629706). However, simultaneous knockdown with only Nep2 has no effect on LTM formation (PubMed:27629706). RNAi-mediated knockdown in somatic muscles is pupal lethal (PubMed:22583317, PubMed:27919317). Muscles of second instar larvae display signs of necrotic degeneration, and undergo fewer and weaker contractions leading to a reduction in their crawling speed (PubMed:22583317). Also displays reduced food intake after 10 minutes (47% of control intake) and 20 minutes of feeding (72% of control intake), but not after 40 minutes (PubMed:27919317). Displays an 82% reduction in expression of insulin-like peptide 4 (PubMed:27919317). Belongs to the peptidase M13 family.