Authors

Discussion

Leishmaniasis and Chagas disease are global infectious diseases for which treatments are challenged and vaccines are not available. The causative agents are digenetic and obligate intracellular protozoan trypanosomatids, that present a peculiar gene expression regulation, occurring preferentially at the post transcriptional level, mediated by trans-regulator elements such as ribonucleoprotein complexes (mRNPs). Our objective is to molecularly verify and characterize RNA Binding Proteins (RBPs) as essential regulators for parasite survival and pathology. 8 amastigote-specific mRNA-bound RBPs were selected that display known RNA-binding domains (Pablos, Ferreira et al., 2019). Knockout lines were generated in L. mexicana for 3 of these and preliminary promastigote growth analysis revealed a decreased replication rate. Another 3 RBPs are likely essential even to promastigote stages as  CRISPR-cas9 assisted knockout has failed repeatedly. For these candidates, a low-cost inducible depletion strategy is being optimized to analyse RBPs essential to all stages. These findings suggest at least 6 relevant targets that contribute to parasite fitness for further investigation, with focus on evaluating the impact upon amastigote stage viability and virulence. Building upon this, 6 RBPs have been tagged for immunoprecipitations to identify RNA targets; providing insight into vulnerable functional pathways. We hope to extend this investigation into orthologous essential RBPs in T. cruzi amastigotes; examining conserved RBP function and the potential for common combative strategies.

Key words: Trypanosomatids, Leishmania, Trypanosoma cruzi, RBP, RNA, Drug Targets.