INSTITUTO DE INVESTIGACIONES BIOTECNOLOGICAS
Unidad Ejecutora - UE
congresos y reuniones científicas
Characterization of a trypomastigote surface glycoprotein regulon involved in Trypanosoma cruzi infectivity
ROMANIUK, M. ALBERTINA; FRASCH, A. CARLOS; SABALETTE, KARINA BELÉN; CASSOLLA, ALEJANDRO; DE GAUDENZI, JAVIER G; NOE, GRISELDA; CAMPO, VANINA A
Congreso; Congreso SAIB; 2018
ABSTRACTRegulation of gene expression in trypanosomatid parasitic protozoa, including Trypanosoma cruzi, the causative agent of Chagas disease, is mostly achieved post-transcriptionally. Organized subsets of RNAs must be co-regulated in response to extracellular signals. Hence regulons, functionally linked mRNAs modulated by trans-acting factors, regain importance. The RNA-binding protein (RBP) TcUBP1 binds a large variety of transcripts including trans-sialidase/trans-sialidase like (TcS) superfamily, a polymorphic group of surface glycoproteins preferentially expressed in the infective forms of the parasite. In vitro RNA-binding assays showed that a 50-nt cis-element highly conserved in the 3?UTR of most TcS family members mediates the interaction with TcUBP1. When steady-state levels of these mRNAs were analyzed by qPCR in replicative non-infective parasites ectopically expressing TcUBP1-GFP, an average of 12 fold increase was observed in comparison to non-induced and GFP induced controls. Moreover, FISH assays revealed that RNA localization of TcS family transcripts change after induction of TcUBP1-GFP to a perinuclear localization, suggesting a subcellular distribution appropriate for RNA translation. In order to elucidate this, TcS family transcripts are being measured in polysomal fractions of both induced and not-induced cultures. Finally, cell derived trypomastigotes obtained from epimastigotes expressing TcUBP1-GFP showed a 2-fold increased infectivity comparing to the non-induced controls. Altogether, our results point to a coordinately up-regulation effect of TcS proteins as a response to induction of TcUBP1 expression, thus reflecting a switch towards trypomastigote-form mRNA expression patterns.