RNA-Seq reveals that overexpression of the RNA-binding protein TcUBP1 switches the gene expression pattern towards that of the infective form of Trypanosoma cruzi

SABALETTE, KB; SOTELO-SILVEIRA, JR; SMIRCICH, P; DE GAUDENZI, JG*

JOURNAL OF BIOLOGICAL CHEMISTRY

AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC

Lugar: Bethesda, Maryland; Año: 2023

0021-9258

Trypanosomesregulate gene expression mainly by using post-transcriptional mechanisms. Keyfactors responsible for carrying out this regulation are RNA-binding proteins(RBPs), affecting subcellular localization, translation, and/or transcriptstability. Trypanosoma cruzi U-rich RBP 1 (TcUBP1) is a small proteinthat modulates the expression of several surface glycoproteins of thetrypomastigote infective stage of the parasite. Its mRNA targets are known butthe impact of its overexpression at the transcriptome level in theinsect-dwelling epimastigote cells has not yet been investigated. Thus, in thepresent study, by using a tetracycline-inducible system, we generated apopulation of TcUBP1-overexpressing parasites and analyzed its effect byRNA-seq methodology. This allowed us to identify 793 up- and 371 down-regulatedgenes with respect to the wild-type control sample. Among the up-regulatedgenes, it was possible to identify members coding for the TcSsuperfamily, MASP, MUCI/II, and protein kinases,whereas among the down-regulated transcripts, we found mainly genes coding forribosomal, mitochondrial, and synthetic pathway proteins. RNA-seq comparisonwith two previously published datasets revealed that the expression profile ofthis TcUBP1-overexpressing replicative epimastigote form resembles thetransition to the infective metacyclic trypomastigote stage. We identifiednovel cis-regulatory elements in the 3´-untranslated region of theaffected transcripts and confirmed that UBP1m -a signature TcUBP1 bindingelement previously characterized in our lab- is enriched in the list ofstabilized genes. We can conclude that the overall effect of TcUBP1overexpression on the epimastigote transcriptome is mainly the stabilization ofmRNAs coding for proteins that are important for parasite infection. *Corresponding author.