Gene networks associated with recovery of Tribolium castaneum after exposure to pyrethroid treated insect netting

The use of pyrethroid-treated long-lasting insecticide netting (LLIN) has become a common stored product pest management strategy. Although effective against many stored product insects, some species can recover after exposure to LLIN in the presence of food, including Tribolium castaneum (Coleoptera: Tenebrionidae). Understanding physiological processes that underly food -mediated recovery are of particular importance to improving the efficacy of LLIN, especially in flour mills and food facilities where flour spillage is common. To identify genes whose expression patterns are linked to recovery in the presence of food, we exposed adult T. castaneum to either alpha cypermethrin -treated LLINor to a sham treatment, then allowed them to recover either in the presence of flour, cellulose (a non-nutritive substrate), or no substrate for up to seven days. After four days LLIN post-exposure, over 60%, 30%, and 0% of the beetles from the flour, cellulose, and no-substrate treatments had recovered. We performed RNA-Seq analysis and gene network co-expression analysis on affected and recovered insects to identify gene networks associated with recovery in the cellulose and flour treatments. We also performed gene ontology and KEGG pathway enrichment analyses on eigengenes of interest, especially those whose expression levels were highest in individuals that had recovered in the presence of cellulose. We discuss our findings and the broader implications of genetic networks which facilitate metabolic recovery and resistance to pyrethroid insecticides.