Cloning and Localization Analysis of a Novel FMRFamide-like Neuropeptide Gene (Dd-flp-1) from Migration Plant-parasitic Nematode (Ditylenchus destructor) on Sweet-potato in China
Abstract：FMRFamide-like peptides (FLPs) play an important role in infection, feeding and reproduction of plant parasitic nematode. A novel FMRFamide-like neuropeptide gene was isolated from Ditylenchus destructor by EST analysis and RACE methods. The full length cDNA of Dd-flp-1 consisted of 891 bp, with a 681 bp ORF encoding a 227 amino acid protein and the predicted molecular weight was 25.36 kD. The protein included a signal peptide of 43 amino acids on the N- terminal and a predicted FMRF domain with five FLPs as NFLRFG on the C- terminal. It was a typical FLP-1-type protein, named Dd-flp-1(GenBank accession No: GU198750). Phylogenic analysis suggested that Dd-FLP-1 had a homology to free live nematodes, animal parasitism nematodes and other migratory plant-parasitic nematodes which might indicate association of the evolution of flp genes from plant parasitism nematodes and their habits. In situ hybridization analysis showed that the transcripts of Dd-flp-1 accumulated exclusively within the circumpharyngeal nerve ring, retrovesicular ganglion and ventral cord of D. destructor. The results suggested that the major functions of DD-FLP-1 were closed with feeding, moving and excreting in D.destructor. This study will provide the foundation and theoretical basis for research on the flp gene function and developing novel plant parasite control targets by RNAi
