Alberto C. Frasch
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Primary Section: 44, Microbial Biology Membership Type:
International Member
(elected 2006)
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Research Interests
Our goal is to understand the organization, function and expression of the molecules present in the surface coat of Trypanosoma cruzi, the protozoan agent of Chagas disease. The surface of this parasite is composed of members of two large families; mucins that are involved in protection and cell invasion, and trans-sialidases that incorporate sialic acid from host glycoconjugates to the parasite mucins. The core proteins of mucins are highly diverse in stages of the parasite in mammals but very similar to each other in the insect parasite stages, suggesting their functioning in immune evasion. Characterization of the primary and 3-dimensional structures of the trans-sialidase allowed demonstration of the function of its different domains and its mechanism of action. Lactose derivatives were shown to be inhibitors of its biological activity preventing parasite infection and the pathology caused by trans-sialidase in cells of the immune system. Coordinate expression of mucins and trans-sialidases in different parasite stages is achieved essentially through posttranscriptional mechanisms involving ribonucleoprotein complexes formation in the 3'untranslated region of the transcripts. More recently our group was involved in the modulation of mRNA expression in the hippocampus of mammals subjected to chronic stress. Studies on M6a, a surface neuronal glycoprotein, suggest the involvement of synaptic plasticity in the response to chronic stress.
