Project description:Comparative genomic analysis of T. cruzi CLB vs Trypanosoma rangeli (strains SC, Choachí, C23, H14, R1625 and PIT10) and Trypanosoma conorhini
Project description:Trypanosoma cruzi is an obligate intracellular protozoan parasite that causes human Chagas’ disease, a leading cause of heart failure in Latin America. Using Affymetrix oligonucleotide arrays we screened phenotypically diverse human cells (foreskin fibroblasts, microvascular endothelial cells and vascular smooth muscle cells) for a common transcriptional response signature to T. cruzi. A common feature was a prominent type I interferon response, indicative of a secondary response to secreted cytokines. Using transwell plates to distinguish cytokine-dependent and -independent gene expression profiles in T. cruzi-infected cells, a core cytokine-independent response was identified in fibroblasts and endothelial cells that featured metabolic and signaling pathways involved in cell proliferation, amino acid catabolism and response to wounding. Significant downregulation of genes involved in mitotic cell cycle and cell division predicted that T. cruzi infection impedes cell cycle progression in the host cell.
Project description:Trypanosoma cruzi is a protozoan parasite and the etiologic agent of Chagas disease, an important public health problem in Latin America. T. cruzi is diploid, almost exclusively asexual, and displays an extraordinarily diverse population structure both genetically and phenotypically. Yet, to date the genotypic diversity of T. cruzi and its relationship, if any, to biological diversity have not been studied at the whole genome level. In this study, we used whole genome oligonucleotide tiling arrays to compare gene content in biologically disparate T. cruzi strains by comparative genomic hybridization (CGH). We observed that T. cruzi strains display widespread and focal copy number variations (CNV) and a substantially greater level of diversity than can be adequately defined by the current genetic typing methods. As expected, CNV were particularly frequent in gene family-rich regions containing mucins and trans-sialidases but were also evident in core genes. Gene groups that showed little variation in copy numbers among the strains tested included those encoding protein kinases and ribosomal proteins, suggesting these loci were less permissive to CNV. Moreover, frequent variation in chromosome copy numbers were observed, and chromosome-specific CNV signatures were shared by genetically divergent T. cruzi strains, suggesting a greater degree of chromosome exchange than previously thought.
Project description:As Trypanosoma cruzi, the etiological agent of Chagas disease, multiplies in the cytoplasm of nucleated host cells, infection with this parasite is highly likely to affect host cells. We performed an exhaustive transcriptome analysis of T. cruzi-infected HeLa cells using an oligonucleotide microarray containing probes for greater than 47,000 human gene transcripts. In comparison with uninfected cells, those infected with T. cruzi showed greater than threefold up-regulation of 41 genes and greater than threefold down-regulation of 23 genes. Real-time reverse transcriptase-polymerase chain reaction (RT-PCR) of selected, differentially expressed genes confirmed the microarray data. Many of these up- and down-regulated genes were related to cellular proliferation, including seven up-regulated genes encoding proliferation inhibitors and three down-regulated genes encoding proliferation promoters, strongly suggesting that T. cruzi infection inhibits host cell proliferation, which may allow more time for T. cruzi to replicate and produce its intracellular nests. These findings provide new insight into the molecular mechanisms by which intracellular T. cruzi infection influences the host cell, leading to pathogenicity. Keywords: infection response
Project description:Trypanosoma cruzi is a protozoan parasite and the etiologic agent of Chagas disease, an important public health problem in Latin America. T. cruzi is diploid, almost exclusively asexual, and displays an extraordinarily diverse population structure both genetically and phenotypically. Yet, to date the genotypic diversity of T. cruzi and its relationship, if any, to biological diversity have not been studied at the whole genome level. In this study, we used whole genome oligonucleotide tiling arrays to compare gene content in biologically disparate T. cruzi strains by comparative genomic hybridization (CGH). We observed that T. cruzi strains display widespread and focal copy number variations (CNV) and a substantially greater level of diversity than can be adequately defined by the current genetic typing methods. As expected, CNV were particularly frequent in gene family-rich regions containing mucins and trans-sialidases but were also evident in core genes. Gene groups that showed little variation in copy numbers among the strains tested included those encoding protein kinases and ribosomal proteins, suggesting these loci were less permissive to CNV. Moreover, frequent variation in chromosome copy numbers were observed, and chromosome-specific CNV signatures were shared by genetically divergent T. cruzi strains, suggesting a greater degree of chromosome exchange than previously thought. Genomic DNA samples from 16 T. cruzi strains were compared to genomic DNA from the CL Brener strain by competitive hybridizations on whole genome oligonucleotide tiling arrays.
Project description:Chagas’ disease, one of the major public health concerns in Latin America, is caused by the haemophlagelated protozoan Trypanosoma cruzi (T. cruzi). In the past few years congenital transmission of T. cruzi has become more important, and partly responsible for the “globalization of Chagas’ disease”. The congenital transmission, although with low rates, represents the main route of transmission in non-endemic countries and endemic countries without vectorial transmission, and represents one third of the new cases each year. Diverse pathogens, including T. cruzi, are able to cross the placental barrier and infect both the placenta and fetus. However, the exact cellular and molecular mechanisms of host-pathogen interaction between T. cruzi and the placenta has been scarcely studied. The use of microarray analysis to determine expression profiles constitutes a powerful tool in order to identify genes and pathways related to the host response to infections. Here, we analyzed the transcriptomic response of human placental chorionic villi explants (HPCVE) challenged with T. cruzi trypomastigotes at low (105) and high (106) concentrations for 2 and 24 hours
Project description:Trypanosoma cruzi dysregulates the gene expression profile of primary human cardiomyocytes (PHCM) during the early phase of infection through a mechanism which remains to be elucidated. The role that small non-coding RNAs (sncRNA) including PIWI-interacting RNA (piRNA) play in regulating gene expression during the early phase of infection is unknown. To understand how T. cruzi dysregulate gene expression in the heart, we challenged PHCM with T. cruzi trypomastigotes and analyzed sncRNA, especially piRNA, by RNA-sequencing. The parasite induced significant differential expression of host piRNAs. An average of 21,595,866 (88.40%) of clean reads mapped to the human reference genome. The parasite induced 217 unique piRNAs that were significantly differentially expressed (q ≥ 0.8). Of these differentially expressed piRNAs, 6 were known and 211 were novel piRNAs. In silico analysis showed that some of the dysregulated known and novel piRNAs could target and potentially regulate the expression of genes reported to play important roles during T. cruzi infection. This is the first report showing that T. cruzi can induce differential expression of piRNAs in PHCM, advancing our knowledge about the involvement of piRNAs in an infectious disease model.
Project description:The intracellular pathogen Trypanosoma cruzi secretes an activity that blocks TGF-β-dependent induction of connective tissue growth factor (CTGF/CCN2). Here, we address the mechanistic basis for T. cruzi-mediated interference of CTGF/CCN2 expression by examining host cell signaling pathways and the global inhibitory effect on TGF-β-dependent gene expression. We show that the expression of a discrete subset of TGF-β-inducible genes involved in cell proliferation, wound repair, and immune regulation are blocked by the soluble T. cruzi activity, demonstrating that this parasite-derived activity has broad, but specific effects on fibroblast gene regulation.
Project description:Trypanosoma cruzi is a protozoan parasite that causes Chagas’ disease in humans and throughout its life cycle faces different environment changes. Protein methylation is an important post-translational modification by which cells respond and adapt to the environment. To understand the importance of protein methylation in T.cruzi biology, we applied mass spectrometry-based proteomics and report the first proteomic analysis of both arginine and lysine methylproteome in T. cruzi.