Zafar_2026_J.Insect.Physiol__104977

The tobacco beetle, Lasioderma serricorne (F.) (Coleoptera: Ptinidae), is a highly adaptable generalist insect pest that inflicts billions of dollars in damage to stored food and tobacco products worldwide. Despite the neurotoxic effects of nicotine, L. serricorne thrives on tobacco, likely due to specific adaptations; however, the underlying molecular mechanisms remain uncharacterized. To investigate, we performed a comparative transcriptome analysis of L. serricorne larvae reared on tobacco versus an artificial diet. Bioinformatic analysis revealed a significant upregulation of genes involved in metabolic detoxification in tobacco fed larvae, including 92 cytochrome P450 (CYPs), 74 ATP-binding cassette (ABC) transporters, 37 glutathione S-transferases (GSTs), 30 UDP-glycosyltransferases (UGTs) and 21 carboxylesterases (CarEs). Spatiotemporal profiling identified several ABC transporters and CYPs as midgut-enriched, indicating roles in xenobiotic metabolism. RNAi-mediated knockdown of LsCYP6TC1, a tobacco-induced CYP, reduced transcript abundance and decreased larval survival to 36.1% compared to controls. Notably, co-silencing of LsABCA1 and LsABCG1 significantly reduced larval survival (77.1%). These results indicate that both Phase I (oxidation via CYPs) and Phase III (efflux via ABC transporters) detoxification play critical roles in tobacco tolerance. Our findings offer valuable insights into insect adaptation to dietary shifts and suggest the specific detoxification genes could be targeted for developing innovative pest management strategies.