This study presents data demonstrating the presence of
FMRFamide-related
peptides (FaRPs) in potato
cyst nematodes (
PCN). Five transcripts of FaRP encoding genes, designated gpflp-1 to gpflp-5, were characterised using RACE. In terms of ORFs, gpflp-1 was 444 base pairs (bp) long and coded for four copies of the FaRP, PF3 (
KSAYMRFamide) whilst gpflp-2 was 309 bp long and encoded one copy of the
peptide, KNKFEFIRFamide. gpflp-3 (420 bp) Encoded two copies of
KHEYLRFamide (
AF2) and the genes gpflp-4 and gpflp-5 encoded a total of 11 FaRPs, most of which are novel to
PCN.
FMRFamide-related
peptide (FaRP)-like immunoreactivity was observed in both
PCN species, Globodera pallida and Globodera rostochiensis, using an antiserum raised against the invertebrate
peptide,
FMRFamide. Immunopositive neurones were found throughout the central nervous system in the ventral and dorsal nerve cords and the circumpharyngeal and perianal nerve rings. Reactive neurones were also present peripherally, innervating the highly muscular pharynx with a nerve net and ring-like structures. Positive immunostaining was also observed in neurones running toward the stylet protractor muscles and/or the anterior sensory apparatus. This study implicates a role for FaRPs in feeding, host penetration and sensory function of
PCN. This is the first study to characterise FaRP encoding genes from a plant-parasitic nematode using a targeted PCR based RACE approach and further underlines the importance and diversity of this
neuropeptide group in the phylum Nematoda.