Differential expression profiles in the midgut of Triatoma infestans infected with Trypanosoma cruzi.

Diego S Buarque,Glória R C Braz,Anita M Tanaka-Azevedo,Cícera M Gomes,Aparecida S Tanaka,Sergio Schenkman,Rafael M Martins,Felipe A A Oliveira

doi:10.1371/journal.pone.0061203

Abstract

Chagas disease, or American trypanosomiasis, is a parasitic disease caused by the protozoan Trypanosoma cruzi and is transmitted by insects from the Triatominae subfamily. To identify components involved in the protozoan-vector relationship, we constructed and analyzed cDNA libraries from RNA isolated from the midguts of uninfected and T. cruzi-infected Triatoma infestans, which are major vectors of Chagas disease. We generated approximately 440 high-quality Expressed Sequence Tags (ESTs) from each T. infestans midgut cDNA library. The sequences were grouped in 380 clusters, representing an average length of 664.78 base pairs (bp). Many clusters were not classified functionally, representing unknown transcripts. Several transcripts involved in different processes (e.g., detoxification) showed differential expression in response to T. cruzi infection. Lysozyme, cathepsin D, a nitrophorin-like protein and a putative 14 kDa protein were significantly upregulated upon infection, whereas thioredoxin reductase was downregulated. In addition, we identified several transcripts related to metabolic processes or immunity with unchanged expressions, including infestin, lipocalins and defensins. We also detected ESTs encoding juvenile hormone binding protein (JHBP), which seems to be involved in insect development and could be a target in control strategies for the vector. This work demonstrates differential gene expression upon T. cruzi infection in the midgut of T. infestans. These data expand the current knowledge regarding vector-parasite interactions for Chagas disease.

Highlights

Parasitic diseases transmitted by arthropods have been some of the most severe causes of human death in the world, especially in developing countries
Yellow fever, dengue and African trypanosomiasis are examples of arthropod-borne diseases transmitted to humans [1]; Chagas disease, or American trypanosomiasis, is another example of this type of disease
Chagas disease remains prevalent in many Latin American countries, affecting an estimated eight million people [3], and it is correlated with poor living conditions

Summary

Introduction

Parasitic diseases transmitted by arthropods have been some of the most severe causes of human death in the world, especially in developing countries. Yellow fever, dengue and African trypanosomiasis are examples of arthropod-borne diseases transmitted to humans [1]; Chagas disease, or American trypanosomiasis, is another example of this type of disease. Chagas disease is caused by the protozoan parasite Trypanosoma cruzi and is transmitted by insects from the Triatominae subfamily [2]. Chagas disease remains prevalent in many Latin American countries, affecting an estimated eight million people [3], and it is correlated with poor living conditions. In contrast to the majority of parasites that transmit arthropod-borne diseases, T. cruzi is not inoculated in the host’s saliva because this protozoan does not infect the salivary glands of the vector insect. The host becomes infected via mucosa or at bite sites [5]

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