AKT-like kinase promotes cell survival during nutritional stress in tripanosomatids

Abstract

Tritryps are protozoan parasites that belong to the Trypanosomatidae family, which encompasses the etiologic agents of leishmaniasis, African and American trypanosomiasis. These parasites undergo different stress conditions across their life cycle, such as nutritional stress, which needs to be deadened in order to guarantee the survival of the parasite inside its vector and mammal hosts. Here we show that the lack of the serine threonine kinase PKB / AKT-like function, either by allosteric inhibition of its Plekstrin domain (PH) in T. cruzi, the reduction of the gene transcripts in T. brucei by RNAi assays, or by AKT-like gene knockout in L. major, reduce the tolerance to nutritional stress of parasites that triggers apoptosis-like events, including DNA fragmentation, mitochondrial damage and loss of plasma membrane integrity. Additionally, we observed that double knockout of Akt-like in L. major impairs its infective capacity. This work confirms some of the previously described functions regarding parasite survival for AKT-like kinases in the Leishmania genus. The present work also provides strong evidence of the probable function of Akt-like in T. cruzi and T. brucei survival and infectivity. Author summaryEndemic countries for neglected tropical diseases are called to play a paramount role in the discovery of new drug candidates through the application of new drug development strategies. Rational drug design method have proven to be compatible with the development of new drug for orphan and neglected diseases since it substantially reduces the costs of discovery and development, a desirable condition for public funded initiatives. Previously we have identified a new parasite protein kinase (AKT-like) as promising new target candidate by means of computational tools and probed its biological role in trypanosomatids. Here we show that inhibition of the AKT-like kinase in trypanosomatids by different approaches (chemical inhibition, interference RNA and gene knockout) decreases the fitness and survival of the parasites in vitro, interfering with the capacity of the parasites to react and survive stress conditions similar to those experienced by the cell in the natural life cycle. Additionally our results strongly supports the potential of a new family of compounds previously described by bioinformatics means as potential trypanocidal agents. Altogether we show that the specific inhibition of the AKT-like is a promising strategy for the further development of anti-trypanosome drugs.