CONICET | Buscador de Institutos y Recursos Humanos

Characterization of the Major Facilitator Superfamily (MFS) proteins of Rhodnius prolixus and study of their role in detoxificationChagas disease affects around eight million people worldwide. The causative agent is the protozoan parasite Trypanosoma cruzi, transmitted to mammals by the feces of triatomine insects.The most important vector species are Triatoma infestans in the Southern Cone and Rhodnius prolixus in the Andean region and in Central America. Given the absence of vaccines and efficienttreatments in the chronic stage, reduction of triatomine population is the method choice for the control of disease. Vector control efforts have been based mainly on the application of pyrethroid insecticides. However, in the last decades it has been repeatedly reported the presence of Triatoma infestans after spraying with pyrethroid insecticides, which was associated with the emergence of insecticide resistance. Hence, the study of detoxification mechanisms and the discovery of targets for new insecticides are fundamental research fields for the improvement of pest managementstrategies. The MFS proteins are ATP-independent and transport a wide range of small solutes in favor of an electrochemical gradient. Previous results of our group indicated a decrease in the expression of some MFS genes after treatment with deltamethrin in T. infestans and after intoxication with an essential oil in Aedes aegypti larvae. These results suggest that some MFS transporters could have a role in the response to xenobiotics. In the present work we carriedout a study of MFS proteins and their implication in detoxification in triatomines using R. prolixus. With the objective of performing a complete characterization of MFS transporters in R. prolixus physiology and their role in the response to a toxic compound, we combined bioinformatic and molecular strategies. First, we performed a phylogenetic analysis of these proteins along with those previously reported in Drosophila melanogaster and T. infestans. These results allowed us toidentify possible candidates to be involved in the response to toxic compounds according to previous results found in those species. We found 7 candidates (RPRC010040, RPRC002229,RPRC010038, RPRC010027, RPRC008199, RPRC003332 and RPRC013855) and Selected RPRC010038 to analyze his expression in different tissues by RT-PCR. We found that it is expressed in crop, fat body, salivary glands, Malpighian tubules, nervous system and midgut, but not in rectum. Moreover, we performed quantitative PCR assays to evaluate gene expression changes after three hours of intoxication with the pyrethroid deltamethrin and we did not find significant changes from control. Here we present the first approach to the study of the role of MFS transporters in triatomine detoxification. The results contribute to the knowledge about detoxifying mechanisms in triatomine insects, valuable for the development of new vector control strategies.