A Trypanosoma cruzi zinc finger protein that is implicated in the control of epimastigote-specific gene expression and metacyclogenesis

Abstract

Trypanosoma cruzi has three biochemically and morphologically distinct developmental stages that are programmed to rapidly respond to environmental changes the parasite faces during its life cycle. Unlike other eukaryotes, Trypanosomatid genomes contain protein coding genes that are transcribed into polycistronic pre-mRNAs and have their expression controlled by post-transcriptional mechanisms. Transcriptome analyses comparing three stages of the T. cruzi life cycle revealed changes in gene expression that reflect the parasite adaptation to distinct environments. Several genes encoding RNA binding proteins (RBPs), known to act as key post-transcriptional regulatory factors, were also differentially expressed. We characterized one T. cruzi RBP, named TcZH3H12, which contains a zinc finger domain and is up-regulated in epimastigotes compared to trypomastigotes and amastigotes. TcZC3H12 knockout (KO) epimastigotes showed decreased growth rates and increased capacity to differentiate into metacyclic trypomastigotes. Transcriptome analyses comparing wild type and TcZC3H12 KOs revealed a TcZC3H12-dependent expression of epimastigote-specific genes such as genes encoding amino acid transporters and proteins associated with differentiation (PADs). RNA immunoprecipitation assays showed that transcripts from the PAD family interact with TcZC3H12. Taken together, these findings suggest that TcZC3H12 positively regulates the expression of genes involved in epimastigote proliferation and also acts as a negative regulator of metacyclogenesis.

Disruption of Active Trans-Sialidase Genes Impairs Egress from Mammalian Host Cells and Generates Highly Attenuated Trypanosoma cruzi Parasites

“…The expression profile of aTS genes was evaluated based on the previously described transcriptome sequencing (RNA-seq) data obtained from tissue culture trypomastigotes and intracellular amastigotes harvested at 60 and 96 h postinfection (hpi) of human fibroblasts ( 20 ). We also incorporated in this analysis RNA-seq data obtained from in vitro cultured epimastigotes of the CL Brener cloned strain, which were more recently reported ( 21 ). Since the RNA-seq reads were mapped to the T. cruzi CL Brener reference genome, available in TriTrypDB, TS mRNA levels based on RNA-seq data were evaluated for only 11 aTS genes.…”

“…The corresponding aTS genes were also retrieved from TriTrypDB v52 ( http://TriTrypDB.org ) after BLAST searches with each sequence used as a query. The RNA-seq data from T. cruzi CL Brener strain during the different life cycle stages, including epimastigotes, trypomastigotes, and amastigotes at 60 and 96 h postinfection, were obtained from our previously published data ( 20 , 21 ). Raw counts were normalized to counts per million (cpm) and converted in log 2 cpm.…”

The gene repertoire of the main cysteine protease of Trypanosoma cruzi, cruzipain, reveals four sub-types with distinct active sites

“…To create the expression profile of cruzipains in T. cruzi ’s life cycle different forms (epimastigote, trypomastigote, and amastigote) , we obtained the RNA-seq data from CL Brener 51 , 52 bioprojects PRJNA389925 and PRJNA389926, respectively, deposited in NCBI database. Read quality was analyzed with FastQC ( http://www.bioinformatics.babraham.ac.uk/ projects/fastqc/) and low-quality reads (Per Sequence Quality Scores < 25 and read length < 50) were removed with Trimmomatic 53 .…”

Kinetoplastid cell biology and genetics, from the 2020 British Society for Parasitology Trypanosomiasis and Leishmaniasis symposium, Granada, Spain

“…Differentiation in T. brucei is induced by the activity of several key mRNA-binding proteins including, but not limited to, zinc-finger proteins (ZFPs) 1, 2 and 3 and RNA-binding proteins (RBPs) 6, 7 and 10. Using T. cruzi transcriptome data from cultured epimastigotes, cultured trypomastigotes and intracellular amastigotes Tavares and colleagues identify differentially expressed RBP-encoding genes (Tavares et al ., 2020). They identify TcZH3H12, a zinc-finger RBP with a T. brucei orthologue that is upregulated in insect-infecting forms.…”