Transcriptomas salivares e intestinais revelam proteínas específicas e expressão gênica diferencial em Rhodnius neglectus infectado e não infectado por Trypanosoma cruzi

Abstract

Rhodnius neglectus is a potential vector of Trypanosoma cruzi (Tc), the causative agent of Chagas disease. During blood feeding, the salivary glands (SGs) and intestine (INT) are actively needed. The saliva of SGs is injected into the vertebrate host, modulating immune responses and favoring feeding for INT digestion. Tc infection significantly alters the physiology of these tissues; however, studies that assess this are still scarce. To better understand them, this study aimed to evaluate the global transcriptional expression of genes in SGs and INT in fasting (FA), Fed (FE) and Fed in the presence of Tc (FE + Tc). In FA, the expression of transcripts related to homeostasis maintenance proteins during periods of stress was predominant. Therefore, transcripts for Tret1-Like and Hsp70Ba proteins were increased. As expected, in the FE group, the presence of blood seemed to be responsible for the alterations found, since most of the expressed transcripts were related to digestion, such as transcripts for the proteases and Cathepsin D. In FE + Tc, there was decrease expression of blood processing genes for the insect metabolism (e.g. Antigen-5 precursor, Pr13a, Obp), detoxication (Sult1) in INT and acid phosphatases in SG. We also found less transcriptional expression of lipocalins and nitrophorins in SG and two new proteins, Pacifastin and Diptericin, in INT. Several transcripts of unknown proteins with investigative potential were found in both tissues. Our results also show that the presence of Tc is capable of altering the expression in both tissues for a long or short time. While in SG homeostasis seems to be reestablished on day 9, changes in INT are still evident. The information generated in this work can serve as a guide for future studies on the parasite-vector interaction and contribute to the understanding of food physiology and post-meal / infection in triatomines.