Fusion proteins containing insect-specific toxins as pest control agents: snowdrop lectin delivers fused insecticidal spider venom toxin to insect haemolymph following oral ingestion.

摘要: The mannose-specific snowdrop lectin (Galanthus nivalis agglutinin: GNA), when fed to insects, binds the gut epithelium and passes into haemolymph. ability of GNA act as a carrier protein deliver an insecticidal spider venom neurotoxin (Segestria florentina toxin 1: SFI1) haemolymph lepidopteran larvae was investigated. Constructs encoding SFI1 SFI1/GNA fusion were expressed in Pichia pastoris. activity purified recombinant proteins on injection found be comparable published values for SfI1 from [Toxicon 40 (2002) 125]. Whereas neither nor alone showed acute toxicity tomato moth (Lacanobia oleracea), feeding at 2.5% dietary first stadium larvae, causing 100% mortality after 6 days. also significant, dose dependent, towards fourth fifth with growth reduced by up approximately 90% over 4-day assay period compared controls. Delivery intact these insects shown western blotting; samples fusion-fed contained GNA-immunoreactive same molecular weight fusion. similar offer novel effective approach delivering active toxins oral administration, which could used crop protection expression transgenic plants.