The physiological Role of the Neuropeptide AF9/FLP21

摘要

FMRFamide-like neuropeptides have potent effects on nematodes. Here we provide an analysis of the physiological role of the neuropeptide FLP-21 (AF9) by defining the phenotype of a flp-21 deletion mutant, pkl601, and by determining the effect of exogenous FLP-21. flp-21(pk1601) animals have impaired locomotion, increased pharyngeal activity and retain eggs as adults. The increased pharyngeal activity of flp-21(pk1601) animals suggests this peptide may exert a tonic inhibitory influence. This is supported by the observation that exogenous FLP-21 inhibits the pharynx. Previous data have indicated that FLP-21 activates the NPY-like receptor, NPR-1. However, npr-1(ky13) animals, which are null for npr-1, do not have the same locomotor, pharyngeal or egg-laying deficit as flp-21(pk1601) animals. We tested whether FLP-21 signals through NPR-1 to inhibit the pharynx and found that npr-1(ky13) animals respond to FLP-21. These data indicate that FLP-21 has a physiological role in regulating the locomotor, pharyngeal and egg-laying circuits of C. elegans and furthermore that it exerts it actions through additonal receptors to NPR-1.