Related Experiment Video
Updated: Oct 29, 2025
Detecting Virus and Salivary Proteins of a Leafhopper Vector in the Plant Host
Published on: September 14, 2021
FMRFamide-Like Peptide 22 Influences the Head Movement, Host Finding, and Infection of Heterodera glycines
Jia You1,2, Fengjuan Pan1, Shuo Wang1
1Key Laboratory of Soybean Molecular Design Breeding, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Harbin, China.
Abstract:
The FMRFamide-like peptides (FLPs) represent the largest family of nematode neuropeptides and are involved in multiple parasitic activities. The immunoreactivity to FMRFamide within the nervous system of Heterodera glycines, the most economically damaging parasite of soybean [Glycine max L. (Merr)], has been reported in previous research. However, the family of genes encoding FLPs of H. glycines were not identified and functionally characterized. In this study, an FLP encoding gene Hg-flp-22 was cloned from H. glycines, and its functional characterization was uncovered by using in vitro RNA interference and application of synthetic peptides. Bioinformatics analysis showed that flp-22 is widely expressed in multiple nematode species, where they encode the highly conserved KWMRFamide motifs. Quantitative real-time (qRT)-PCR results revealed that Hg-flp-22 was highly expressed in the infective second-stage juveniles (J2s) and adult males. Silencing of Hg-flp-22 resulted in the reduced movement of J2s to the host root and reduced penetration ability, as well as a reduction in their subsequent number of females. Behavior and infection assays demonstrated that application of synthetic peptides Hg-FLP-22b (TPQGKWMRFa) and Hg-FLP-22c (KMAIEGGKWVRFa) significantly increased the head movement frequency and host invasion abilities in H. glycines but not in Meloidogyne incognita. In addition, the number of H. glycines females on the host roots was found to be significantly higher in Hg-FLP-22b treated nematodes than the ddH2O-treated control J2s. These results presented in this study elucidated that Hg-flp-22 plays a role in regulating locomotion and infection of H. glycines. This suggests the potential of FLP signaling as putative control targets for H. glycines in soybean production.
Insights
The FMRFamide-like peptide 22 (Hg-flp-22) gene in soybean cyst nematode regulates movement and root invasion. Targeting this gene offers potential control strategies for this damaging parasite.
Area of Science:
- Nematology
- Molecular Biology
- Biochemistry
Background:
- FMRFamide-like peptides (FLPs) are crucial for nematode parasitic activities.
- The soybean cyst nematode (SCN), *Heterodera glycines*, is a major threat to soybean production.
- Genes encoding FLPs in *H. glycines* remained uncharacterized.
Purpose of the Study:
- To clone and functionally characterize the *Hg-flp-22* gene in *H. glycines*.
- To investigate the role of *Hg-flp-22* in nematode locomotion and host infection.
- To explore the potential of FLP signaling as a control target for SCN.
Main Methods:
- Gene cloning and bioinformatics analysis of *Hg-flp-22*.
- In vitro RNA interference (RNAi) to silence *Hg-flp-22* expression.
- Application of synthetic Hg-FLP-22 peptides in behavioral and infection assays.
Main Results:
- *Hg-flp-22* is conserved across nematode species and highly expressed in infective J2s and adult males.
- Silencing *Hg-flp-22* impaired J2 movement, root penetration, and subsequent female development.
- Synthetic Hg-FLP-22 peptides enhanced *H. glycines* locomotion and invasion, increasing female numbers.
Conclusions:
- *Hg-flp-22* plays a significant role in regulating *H. glycines* locomotion and host infection.
- FLP signaling represents a promising target for developing novel SCN control strategies.
- This research provides insights into nematode neuropeptide function and pest management.
