FMRFamides and FMRFamide-like peptides are neuropeptides. Potent inhibitor of the activity of the dissected pharyngeal myogenic muscle system (PubMed:16187307). Acts as a ligand for the npr-22 receptor in vitro (PubMed:16377032). Acts as a ligand for the npr-22 receptor in vitro. Acts as a ligand for the npr-22 receptor in vitro. Each flp gene is expressed in a distinct set of neurons (PubMed:15236235). Flp-11 is expressed in the DD, VD and DVB motor neurons, the PVC and URX interneurons, and the AUA, BAG, DA, LUA, and SAB neurons (PubMed:15236235). Also expressed in head muscle, socket or sheath cells and uterine cells (PubMed:15236235). Expressed exclusively in PHC sensory neurons in males (PubMed:15236235, PubMed:28065609). Expressed from the comma stage of embryogenesis, during all larval stages, and in adults (PubMed:9685599). In males, highly expressed in PHC sensory neurons during the L4 larval stage (PubMed:28065609). Belongs to the FARP (FMRFamide related peptide) family.