During FMRFamide-like peptide (FaRPs or FLP) and neuropeptide-like protein (NLP) precursor processing, catalyzes the removal of Arg or Lys residues from the C-terminus following the initial endoprotease cleavage (PubMed:17564681, PubMed:12657671). By processing neuropeptides, modulates basal acetylcholine release at the ventral cord neuromuscular junctions (PubMed:12657671, PubMed:22275875). Involved in egg-laying, defecation and locomotion (PubMed:11813735, PubMed:17564681, PubMed:22275875). By processing FLP neuropeptides, regulates the turning step of male mating behavior (PubMed:17611271). Involved in reducing pharyngeal pumping in response to high CO(2) levels (PubMed:25101962). Release of C-terminal arginine or lysine residues from polypeptides. Binds 1 zinc ion per subunit. Predominantly localizes to axons in the nerve ring. Expression is restricted to the nervous system. Belongs to the peptidase M14 family.