Furin-like protease which cleaves proproteins at the RX(K/R)R consensus motif (PubMed:24671950). During neuronal development, regulates the formation and extension of dendrite branches and cellular positioning of various type of neurons (PubMed:23932402, PubMed:25232734, PubMed:26974341, PubMed:28846083). Together with chin-1 and cdc-42, plays a role in the development of the neuropil and is required for the guidance of axons from neurons, including SubL pioneer neurons and AIY interneurons, into the nerve ring (PubMed:28846083). Its role in axon guidance in glia and pioneer neurons may be through ensuring the fmi-1 protein is correctly localized to the nerve ring (PubMed:28846083). Promotes the formation, extension and self-avoidance of dendritic branches of PVD and FLP mechanosensory neurons (PubMed:23932402, PubMed:25232734, PubMed:26974341). In PVD neurons, regulates plasma membrane levels of branching receptor dma-1 by targeting it to late endosomes and thus promotes normal dendrite branching and dendrite self-avoidance (PubMed:26974341). Also controls dendrite extension in AIY and D-type motoneurons, dendrite branching in AQR sensory neurons and VC4/5 motoneurons, the normal number of dendritic branches in AVL neurons and the positioning of HSN and ALM/PLM neurons (PubMed:25232734). Dispensable for maintaining dendrite branching in adults (PubMed:25232734). Also regulates dauer-specific dendritic branching of IL2 neurons and dauer-specific nictation behavior (PubMed:23932402). Under adverse environmental conditions, may promote dauer formation by processing insulin-like proteins ins-1 and ins-18, two daf-2/InsR antagonists (PubMed:24671950). Binds 3 calcium ions per subunit. Interacts (via extracellular domain) with receptor dma-1 (via extracellular domain); the interaction promotes dma-1 internalization. In most neurons, localizes exclusively within the cell bodies, but in ventral cord neurons, localizes in both the neuronal cell bodies and processes. Expressed in the nervous system including the ventral nerve cord, the nerve ring and the retrovesicular ganglion, and in epithelial cells (PubMed:23932402, PubMed:24671950, PubMed:25232734). Expressed in IL2 neurons (PubMed:23932402). Expressed in PVD mechanosensory neurons (PubMed:25232734). Expressed in pharynx with strong expression in the g2 pharyngeal gland cells and vpi pharyngeal intestinal valve cells (PubMed:23932402, PubMed:25232734). Expressed in intestine (PubMed:24671950). Expressed in embryos, larvae and adults (PubMed:25232734). Broadly expressed in embryos (PubMed:28846083). Expressed broadly in neuronal and epithelial cells throughout the head during the dauer stage (PubMed:23932402). Several defects in neuron development (PubMed:25232734, PubMed:26974341). In PVD mechanosensory neurons, tertiary and quaternary branching is decreased, secondary and ectopic tertiary branching is increased, the length of dendritic branches is also reduced and branches tend to overlap (PubMed:25232734, PubMed:26974341). Secondary dendrite branches are trapped next to primary branches (PubMed:26974341). In a sax-7 (nj48) or dma-1 (wy686) mutant background, significantly less secondary dendrites are trapped (PubMed:26974341). Increased dma-1 protein levels in PVD neuron dendrites (PubMed:26974341). In addition, abnormal dendrite branches in FLP neurons, reduced axonal extension in AIY interneurons, abnormal positioning of touch receptor ALM and HSN motoneuron, formation of ectopic branching in AVL, loss of sensory AQR branching in the nerve ring, and impaired extension and formation of branches near the vulva in VC4/5 motoneurons (PubMed:26974341). RNAi-mediated knockdown at the L1 larval stage but not at the L4 larval stage causes defects in the dendritic branching of PVD neurons (PubMed:26974341). Belongs to the peptidase S8 family. Furin subfamily.