CONICET | Buscador de Institutos y Recursos Humanos

The AMP-activated protein kinase (AMPK) is a heterotrimeric enzyme involved in maintaining energy homeostasis in many organisms. Trypanosoma cruzi, the causative agent of Chagas disease, affects between 6 and 7 million people. During the transition between the mammal host and the insect vector, T. cruzi faces nutritional, oxidative, osmotic and other types of stress, all of which can prompt the parasite to remodel its metabolism and force it to re-establish their homeostasis. The ability to respond to stress, allows the parasite to differentiate and survive. It was shown that T. brucei AMPK is involved in the differentiation from the slender to stumpy stages and in surface protein expression changes in response to nutritional stress. We identified four candidates for the AMPK subunits of T. cruzi (α1 and α2 catalytic subunits, β and γ regulatory subunits). Its expression in T. cruzi epimastigotes was confirmed by RT-PCR, Western blot with a phospho-AMPKα specific antibody, mass spectrometry and by incorporation of 32P to the specific AMPK substrate SAMS in a kinase activity assay. This last assay also allowed us to observe the upregulation of AMPK activity under epimastigote starvation, and the inhibition of this activity with dorsomorphin, a specific inhibitor. Also, each of these subunits can revert the ‗glucose dependent? phenotype of S. cerevisiae conditional mutants alternatively lacking one subunit of the AMPK ortholog SNF1. Our results show, for the first time, the presence of a functional AMPK ortholog in T. cruzi. In the future, we aim to discover its role through the life cycle and stress responses of this parasite.