STEADY-STATE mRNA LEVELS OF NUMEROUS SURFACE GLYCOPROTEINS THAT ARE EXPRESSED IN THE BLOODSTREAM FORM OF THE PARASITE TRYPANOSOMA CRUZI ARE COORDINATELY REGULATED BY TcUBP1

SABALETTE, KARINA B; ROMANIUK, ALBERTINA; NOÉ, GRISELDA ; CASSOLA, ALEJANDRO; FRASCH, ALBERTO C. C.; CAMPO VA; DE GAUDENZI JG

Buenos Aires

Congreso; XXIX REUNIÓN ANUAL DE LA SOCIEDAD ARGENTINA DE PROTOZOOLOGÍA; 2017

Regulation of gene expressionin trypanosomatid parasitic protozoa, including species with complex life cyclesthat cause neglected tropical diseases, is mostly achievedposttranscriptionally. RNA regulons consist of ribonoucleoprotein complexesthat respond to exogenous and/or endogenous cell signals to regulate theco-expression of functionally related proteins. In this regards, TcUBP1 (T. cruzi U-rich RBP 1) plays roles inmRNA turnover and binds transcripts harboring a signature element in their 3′ untranslated regions (UTRs).Among UBP1 targets we found a subset of the TcS (Trans-sialidase/Trans-sialidase-like) superfamily, a largegroup of glycoprotein molecules that are differentially expressed in themammalian stage of the parasite (trypomastigote). The aim of our work is toanalyze the impact of the TcUBP1-TcSinteraction, and the biological function of this RBP as a regulatory factor ofthis gene family. For this purpose, we first analyzed by qPCR the expression offour representative members in two stages of T. cruzi CL Brener wild type parasites, together with a commontarget by amplifying a conserved region present in most of the TcS targets3′ UTRs. Wefound a clear enrichment of 10 to 70 fold difference in infective stagetrypomastigotes over non-infective stage epimastigotes only in TcS transcritps but not in RNA controls(p<0.05, type 3 T-test). Then, a TcUBP1-GFP construction or GFP, as acontrol, was cloned into the pTcINDEX tetracycline inducible vector andtransfected in transgenic epimastigotes expressing tetR. Overexpression of TcUBP1in these cells demonstrated a consequent increase of 5 to 20 times of the TcS targets regarding not induced or GFPcontrols (p<0.05, type 3 T-test). Altogether, our results suggest acoordinately up-regulation effect of numerous TcS transcripts as a specific response to TcUBP1, which could beinvolved in controlling differential expression of trypomastigote surfaceglycoproteins.