Delivery of intrahemocoelic peptides for insect pest management

•Transcytosis across the gut epithelium can be exploited for insect pest control.•Luteovirus coat proteins deliver neurotoxins from the insect gut into the hemocoel.•Plant lectins also deliver intrahemocoelic toxins from the insect gut.•Entomopathogenic fungi deliver intrahemocoelic toxins via the insect cuticle.

The extensive use of chemical insecticides for insect pest management has resulted in insecticide resistance now being recorded in >500 species of insects and mites. Although gut-active toxins such as those derived from Bacillus thuringiensis (Bt) have been successfully used for insect pest management, a diverse range of insect-specific insecticidal peptides remains an untapped resource for pest management efforts. These toxins act within the insect hemocoel (body cavity) and hence require a delivery system to access their target site. Here, we summarize recent developments for appropriate delivery of such intrahemocoelic insect toxins, via fusion to a second protein such as a plant lectin or a luteovirus coat protein for transcytosis across the gut epithelium, or via entomopathogenic fungi.