Characterization of Odorant Binding and Chemosensory Protein Families in the kissing bug Triatoma infestans; comparative analysis among Heteroptera species

Background Plasticity for detoxification and sensory perception contributes to insects' adaptive capacities and evolutive success, by coping with xenobiotics from the environment or the internal medium. Odorant binding proteins and chemosensory proteins have been traditionally studied in the context of chemoperception. Accumulated evidence from the last few years indicates that these protein families can also mediate insecticide sequestration, leading to a better detoxification and insecticide resistance. The kissing bug Triatoma infestans is the main vector of Trypanosoma cruzi , the protozoan parasite causing Chagas’ disease, in the South Cone. Vectorial transmission of T. cruzi has not been stopped in regions from Argentina where several populations of T. infestans highly resistant to insecticides were reported. Understanding the associated molecular mechanisms of resistance is crucial for designing effective vector control interventions. For this, the study of protein families involved in detoxification is essential. Results We manually corrected predicted gene models and identified new sequences of chemosensory and odorant binding proteins in five Hemiptera species with different feeding habits. Using this information, we data-mined the raw genome sequence of T. infestans to identify and characterize their orthologous by sequence conservation and phylogenetic associations. In total, 26 chemosensory and 49 odorant binding proteins were identified in T. infestans genomic sequence. Phylogenetic analysis, tissue-specific expression and molecular docking with major insecticides were performed to assess possible roles. Conclusions This work represents the first comprehensive genomic analysis of chemosensory and odorant binding protein families across Hemiptera species, and the first characterization of gene families in T. infestans using genomic information. This work contributes to a better understanding of the molecular basis of chemoreception and insecticide resistance in T. infestans .