Secreted metalloprotease required for distal tip cell (DTC) migration along the body wall basement membranes, a key step that promotes gonad morphogenesis (PubMed:10588887, PubMed:10376599, PubMed:15556862). Probably acts by remodeling the basement membrane during cell migration (PubMed:10376599). Required to restrict presynaptic growth at the neuromuscular junctions (NMJ) in late larval stage and in adult motor neurons, probably by controlling collagen IV emb-9 degradation, a component of the synapse basement membrane (PubMed:25080592, PubMed:25232106). Also involved in the organization of adult muscle morphology (PubMed:25232106). Has a protease-independent function in promoting the transport from the endoplasmic reticulum to the Golgi apparatus of a variety of secretory cargos (PubMed:22419820, PubMed:26218657). Required for the secretion of insulin-like peptide ins-7, daf-28 and ins-18 and TGF beta-like protein daf-7 (PubMed:26218657). In peripheral tissues, negatively regulates insulin-mediated daf-16 translocation and thereby negatively regulates lifespan and dauer formation (PubMed:26218657). Binds 1 zinc ion per subunit. Expressed by the gonadal distal tip cells (DTCs) (PubMed:10376599). Expressed in muscles, including body wall, vulval and anal depressor muscles (PubMed:10376599, PubMed:25232106, PubMed:26218657). Expressed in motor neurons and in ASI and ASJ neurons (PubMed:26218657). Expressed in some cells at the embryonic stage (260-280 min after the first cleavage) (PubMed:26218657). In hermaphrodites, expression is first detected in gonads in L2 larvae and is limited to the distal tip cells (DTCs), then continues in DTCs throughout L4 larval stage and becomes faint or absent in adults (PubMed:10376599). Also expressed in muscle cells throughout development (PubMed:10376599). At the larval stages, expressed in some head neurons, intestine and excretory cells (PubMed:26218657). The GON domain mediates protease-independent function in ER to Golgi transport. RNAi-mediated knockdown in distal tip cells results in deformation of ER structure and inhibition of protein secretion which are rescued upon GON-domain expression.