Transcriptome Analysis of the Triatoma infestans (Hemiptera: Reduviidae) Integument

MORICONI, DÉBORA E; DULBECCO, ANDREA B.; JUÁREZ, M PATRICIA; CALDERÓN-FERNÁNDEZ, G. M

Congreso; REUNIÓN CONJUNTA DE SOCIEDADES DE BIOCIENCIAS; 2017

The insect integument, formed by the cuticle and the underlying epidermis, is essential to insect fitness, regulating lipid biosynthesis and storage, insect growth and development. Its participation in insecticide resistance was recently shown in Triatoma infestans; one of the major vectors of Chagas disease in South America. Cuticle thickening together with larger amounts of cuticular hydrocarbons contribute to the cuticular resistance factor in insecticide resistant populations,however, genomic data is scarce. In this study, we performed a transcriptome analysis of the nymph integument in order to identify the genes expressed and their potential role. More than 10% of the transcripts encoded proteins putatively involved in the metabolism of fatty acids and related components (fatty acid synthases, elongases, desaturases, fatty alcohol reductases), structural integument proteins, and components of the insecticide detoxification system (cytochrome P450s, esterases and glutathione transferases). Present work showed a differential expression pattern of several genes related to cuticle lipid biosynthesis, cuticle formation and insecticide detoxification in pyrethroid-resistant insects. These results suggest that the overexpression of some integument genes may contribute to insecticide resistance in T. infestans through mechanisms not only involving a delayed penetration through the cuticle, but also an increased detoxification of the insecticide. The function of relevant genes potentially involved in insecticide resistance was studied by RNA interference. This is the first transcriptome analysis of a triatomine integument, and together with prior biochemical information, will help further understand the integument role in a wide array of mechanisms