Publication details for Dr Elaine FitchesYang, S., Pyati, P., Fitches, E. & Gatehouse, J.A. (2014). A recombinant fusion protein containing a spider toxin specific for the insect voltage-gated sodium ion channel shows oral toxicity towards insects of different orders. Insect Biochemistry and Molecular Biology 47: 1-11.
- Publication type: Journal Article
- ISSN/ISBN: 0965-1748 (print)
- DOI: 10.1016/j.ibmb.2014.01.007
- Keywords: Neurotoxin, Insecticide, Recombinant protein expression system, Protein transport, Crop protection, Biotechnology.
- Further publication details on publisher web site
- Durham Research Online (DRO) - may include full text
Author(s) from Durham
Recombinant fusion protein technology allows specific insecticidal protein and peptide toxins to display activity in orally-delivered biopesticides. The spider venom peptide δ-amaurobitoxin-PI1a, which targets insect voltage-gated sodium channels, was fused to the “carrier” snowdrop lectin (GNA) to confer oral toxicity.
The toxin itself (PI1a) and an amaurobitoxin/GNA fusion protein (PI1a/GNA) were produced using the yeast Pichia pastoris as expression host. Although both proteins caused mortality when injected into cabbage moth (Mamestra brassicae) larvae, the PI1a/GNA fusion was approximately 6 times as effective as recombinant PI1a on a molar basis. PI1a alone was not orally active against cabbage moth larvae, but a single 30 μg dose of the PI1a/GNA fusion protein caused 100% larval mortality within 6 days when fed to 3rd instar larvae, and caused significant reductions in survival, growth and feeding in 4th – 6th instar larvae. Transport of fusion protein from gut contents to the haemolymph of cabbage moth larvae, and binding to the nerve chord, was shown by Western blotting. The PI1a/GNA fusion protein also caused mortality when delivered orally to dipteran (Musca domestica; housefly) and hemipteran (Acyrthosiphon pisum; pea aphid) insects, making it a promising candidate for development as a biopesticide.