TcZC3HTTP, a regulatory element that contributes to Trypanosoma cruzi cell proliferation

Abstract Post-transcriptional regulation of gene expression is a critical process for adapting and surviving Trypanosoma cruzi , a parasite with a complex life cycle. RNA binding proteins (RBPs) are key players in this regulation, forming ribonucleoprotein complexes (mRNPs) and RNA granules that control transcript stability, localization, degradation, and translation modulation. Understanding the specific roles of individual RBPs is crucial for unraveling the details of this regulatory network. In this study, we generated null mutants of the TcZC3HTTP gene, a specific RBP in the Trypanosoma family, characterized by a C3H zinc finger and a DNAJ domain associated with RNA and protein binding, respectively. Through cell growth assays, we demonstrated that the absence of TcZC3HTTP or the expression of an additional tagged version significantly impacted epimastigote growth, indicating its contribution to cell proliferation. TcZC3HTTP was found to associate with mRNAs involved in cell cycle and division in epimastigotes, while nutritionally stressed parasites exhibited associations with mRNAs coding for other RBPs and rRNA. Furthermore, our analysis of TcZC3HTTP protein partners revealed the presence of several enzymes during normal growth conditions, whereas starvation conditions enriched ribosomal proteins and other RBPs. This study provides insights into the post-transcriptional regulation of gene expression in T. cruzi , highlighting the role of TcZC3HTTP as an RBP involved in cell proliferation and uncovering its versatile functions in different cellular contexts. Importance Understanding how Trypanosoma cruzi , the causative agent of Chagas disease, regulates gene expression is crucial for developing targeted interventions. In this study, we investigated the role of TcZC3HTTP, an RNA binding protein, in post-transcriptional regulation. Our findings demonstrate that TcZC3HTTP is essential for the growth and proliferation of epimastigotes, a stage of the parasite’s life cycle. We identified its associations with specific mRNAs involved in cell cycle and division and its interactions with enzymes and other RBPs under normal and starvation conditions. These insights shed light on the regulatory network underlying gene expression in T. cruzi and reveal the multifaceted functions of RBPs in this parasite. Such knowledge enhances our understanding of the parasite’s biology and opens avenues for developing novel therapeutic strategies targeting post-transcriptional gene regulation in T. cruzi .