Structural and functional analysis of TcCARP1 and TcCARP3 in Trypanosoma cruzi

GABRIEL FERRI; IVAN CAMPEOTTO; MARTIN M. EDREIRA

Mar del Plata

Congreso; XXXI Reunión Anual de la Sociedad Argentina de Protozoología (SAP); 2019

Sociedad Argentina de Protozoología

With no vaccines or new drugs developed in the last 50 years, Chagas Disease treatment currently relies entirely in two drugs introduced in the 70s, benznidazole and nifurtimox. These drugs produce serious side effects including sterility and blindness and are not effective during the chronic stages of the infection. Accordingly, there is an urgent need of more efficient and better-tolerated therapies. Several strategies have been followed to expand the repertoire of new anti-parasitic drugs. Among these strategies is targeted drug design, based in the screening for inhibitors against distinguish molecular targets, usually a protein with an enzymatic activity. An effective molecular target must be an essential gene, that could be inhibited (druggable) to achieve a lost in viability and virulence of the parasite. In addition, the ideal target should be parasite-specific, with no counterparts in humans, but with orthologs in other trypanosomatid pathogen. Within these potential targets are signal transduction pathways, which have so far remained largely unexplored in trypanosomatids. Of special interest is cAMP-mediated signaling, since cAMP has been shown to play critical roles in T. cruzi cell cycle and host cell invasion. In this regard, the relevance of cAMP-mediated signalling in another closely related parasite, T. brucei, was demonstrated by the pharmacological validation of trypanosomal phosphodiesterases (PDEs) as drug targets, the inhibition of which caused a dramatic increase of intracellular cAMP, immediately stalling cell proliferation and triggering cell death within days. Furthermore, on the track of resistance to T. brucei PDE inhibitors were identified a group of kinetoplastid unique proteins, called cAMP Response Proteins (CARPs), as mediators of the cAMP signalling involved in cell death. The present research focuses on the identification and characterization of TcCARP1 and TcCARP3 from T. cruzi, both sui generis to kinetoplastids. It has been shown that TcCARP1 and TcCARP3 presented a significant increase in both gene expression and protein translation during host cell invasion, only in virulent strain parasites. The aim of this research was to elucidate CARPs mediated signaling in T. cruzi, through protein-protein studies, subcellular localization and oxidative stress assays; providing structural and functional analysis of CARPs proteins, not only to increase our knowledge about T. cruzi biology but also to target CARPs for the design and development of novel therapeutic agents against Chagas disease.