Identification of immunological expressed sequence tags in the mealworm beetle Tenebrio molitor

Understanding the evolutionary ecology of immune responses to persistent infection could provide fundamental insight into temporal dynamics or interactive mechanisms that could be co-opted for antibiotic treatment regimes. Additionally, identification of novel molecules involved in these processes could provide novel compounds for biotechnological development. The beetle Tenebrio molitor displays a high level of induced antimicrobial activity coincident with persistent immuno-resistant Staphylococcus aureus, and is the first invertebrate model for persistent infection. Here we present expressed sequence tags (ESTs) detected by suppression-subtraction hybridization of Tenebrio larvae after infection with S. aureus. Amongst others, we identified mRNAs coding for various oxidative enzymes and two antimicrobial peptides. These ESTs provide a foundation for mechanistic study of Tenebrio's immune system.

Highlights► Tenebrio molitor is the only insect model for persistent infection. ► SSH used to study expressed sequence tags after infection with gram+S. aureus. ► We observed the up-regulation of numerous oxidative enzymes. ► We also find the strong up-regulation of two antimicrobial peptides. ► Interestingly one of them is an attacin, known to be active against gram− bacteria.