Publication details for Dr Elaine FitchesYang, S., Fitches, E., Pyati, P. & Gatehouse, J.A. (2015). Effect of insecticidal fusion proteins containing spider toxins targeting sodium and calcium ion channels on pyrethroid-resistant strains of peach-potato aphid (Myzus persicae). Pest Management Science 71(7): 951-956.
- Publication type: Journal Article
- ISSN/ISBN: 1526-498X, 1526-4998
- DOI: 10.1002/ps.3872
- Keywords: Biopesticide, Insecticide resistance, Homoptera/Hemiptera, Voltage-gated ion channels, Fitness cost.
- Further publication details on publisher web site
- Durham Research Online (DRO) - may include full text
Author(s) from Durham
BACKGROUND: The recombinant fusion proteins Pl1a/GNA and Hv1a/GNA contain the spider venom peptides δ-amaurobitoxin-PI1a or ω-hexatoxin-Hv1a respectively, linked to snowdrop lectin (GNA). Pl1a targets receptor site 4 of insect voltage-gated sodium channels (NaCh), while Hv1a targets voltage-gated calcium channels. Insecticide-resistant strains of peach-potato aphid (Myzus persicae) contain mutations in NaCh. The pyrethroid-resistant kdr (794J) and super-kdr (UKO) strains contain mutations at residues L1014 and M918 in the channel α-subunit respectively, while the kdr + super-kdr strain (4824J), insensitive to pyrethroids, contains mutations at both L1014 and M918.
RESULTS: Pl1a/GNA and Hv1a/GNA fusion proteins have estimated LC50 values of 0.35 and 0.19 mg mL−1 when fed to wild-type M. persicae. For insecticide-resistant aphids, LC50 for the Pl1a/GNA fusion protein increased by 2–6-fold, correlating with pyrethroid resistance (wild type < kdr < super-kdr < kdr + super-kdr strains). In contrast, LC50 for the Hv1a/GNA fusion protein showed limited correlation with pyrethroid resistance.
CONCLUSION: Mutations in the sodium channel in pyrethroid-resistant aphids also protect against a fusion protein containing a sodium-channel-specific toxin, in spite of differences in ligand–channel interactions, but do not confer resistance to a fusion protein targeting calcium channels. The use of fusion proteins with differing targets could play a role in managing pesticide resistance.