Visualization and 3D Reconstruction of Flame Cells of Taenia solium (Cestoda)

BACKGROUND: Flame cells are the terminal cells of protonephridial systems, which are part of the excretory systems of invertebrates. Although the knowledge of their biological role is incomplete, there is a consensus that these cells perform excretion/secretion activities. It has been suggested that the flame cells participate in the maintenance of the osmotic environment that the cestodes require to live inside their hosts. In live Platyhelminthes, by light microscopy, the cells appear beating their flames rapidly and, at the ultrastructural, the cells have a large body enclosing a tuft of cilia. Few studies have been performed to define the localization of the cytoskeletal proteins of these cells, and it is unclear how these proteins are involved in cell function. METHODOLOGY/PRINCIPAL FINDINGS: Parasites of two different developmental stages of T. solium were used: cysticerci recovered from naturally infected pigs and intestinal adults obtained from immunosuppressed and experimentally infected golden hamsters. Hamsters were fed viable cysticerci to recover adult parasites after one month of infection. In the present studies focusing on flame cells of cysticerci tissues was performed. Using several methods such as video, confocal and electron microscopy, in addition to computational analysis for reconstruction and modeling, we have provided a 3D visual rendition of the cytoskeletal architecture of Taenia solium flame cells. CONCLUSIONS/SIGNIFICANCE: We consider that visual representations of cells open a new way for understanding the role of these cells in the excretory systems of Platyhelminths. After reconstruction, the observation of high resolution 3D images allowed for virtual observation of the interior composition of cells. A combination of microscopic images, computational reconstructions and 3D modeling of cells appears to be useful for inferring the cellular dynamics of the flame cell cytoskeleton

Privatisation and quasi-markets

Paper presented at the EACES First Trento Workshop, University of Trento (IT), 1-2 Mar 1991Available from British Library Document Supply Centre- DSC:8490.3304(7) / BLDSC - British Library Document Supply CentreSIGLEGBUnited Kingdo

Expression of Proteins, Glycoproteins, and Transcripts in the Guts of Fasting, Fed, and <i>Trypanosoma cruzi</i>-Infected Triatomines: A Systematic Review

Chagas disease is caused by the hemoflagellate protozoan Trypanosoma cruzi. The main transmission mechanism for the parasite in endemic areas is contact with the feces of an infected triatomine bug. Part of the life cycle of T. cruzi occurs in the digestive tract of triatomines, where vector and parasite engage in a close interaction at a proteomic–molecular level. This interaction triggers replication and differentiation processes in the parasite that can affect its infectivity for the vertebrate host. With the aim of compiling and analyzing information from indexed publications on transcripts, proteins, and glycoproteins in the guts of fasting, fed, and T. cruzi-infected triatomines in the period 2000–2022, a systematic review was conducted following the PRISMA guidelines. Fifty-five original research articles retrieved from PubMed and ScienceDirect were selected; forty-four papers reported 1–26,946 transcripts, and twenty-one studies described 1–2603 peptides/proteins

Identification of O-Glcnacylated Proteins in Trypanosoma cruzi

International audienceOriginally an anthropozoonosis in the Americas, Chagas disease has spread from its previous borders through migration. It is caused by the protozoan Trypanosoma cruzi. Differences in disease severity have been attributed to a natural pleomorphism in T. cruzi. Several post-translational modifications (PTMs) have been studied in T. cruzi, but to date no work has focused on O-GlcNAcylation, a highly conserved monosaccharide-PTM of serine and threonine residues mainly found in nucleus, cytoplasm, and mitochondrion proteins. O-GlcNAcylation is thought to regulate protein function analogously to protein phosphorylation; indeed, crosstalk between both PTMs allows the cell to regulate its functions in response to nutrient levels and stress. Herein, we demonstrate O-GlcNAcylation in T. cruzi epimastigotes by three methods: by using specific antibodies against the modification in lysates and whole parasites, by click chemistry labeling, and by proteomics. In total, 1,271 putative O-GlcNAcylated proteins and six modification sequences were identified by mass spectrometry (data available via ProteomeXchange, ID PXD010285). Most of these proteins have structural and metabolic functions that are essential for parasite survival and evolution. Furthermore, O-GlcNAcylation pattern variations were observed by antibody detection under glucose deprivation and heat stress conditions, supporting their possible role in the adaptive response. Given the numerous biological processes in which O-GlcNAcylated proteins participate, its identification in T. cruzi proteins opens a new research field in the biology of Trypanosomatids, improve our understanding of infection processes and may allow us to identify new therapeutic targets

Immunolocalization of nuclei after staining with DAPI of control, T₄- and DHT-treated cysticerci.

<p>Phase contrast of the control sections of the slides obtained by Tissue-Teck fixing are shown in upper panel from left to right, control (C), testosterone (T₄) and dihydrotestosterone (DHT). In lower panel, DAPI was used to detect nuclei in frozen tissue sections fixed with Tissue-Teck. Treatment with both steroids induced changes in the distribution of nuclei, which also affected the morphology of FCs. Cysticerci were observed under an SEM Zeiss DSM-950 after five days of treatment with 50 μg/ml of each steroid. Scale bar corresponds to 10 μm.</p

Immunolocalization of α-tubulin (green) of control, T₄ and DHT treated parasites.

<p>Phase contrast of the control sections of the slides obtained by Tissue-Teck fixing are shown in upper panel from left to right, control (C), testosterone (T₄) and dihydrotestosterone (DHT). In lower panel, green tiny spots are produced by the specific binding of the anti-α-tubulin stained with alexa-488 antibody to cytoskeletal α-tubulin. Tubulin protein inside the bladder wall and at the level of the tegument in the tissue of control parasites and those treated with T₄ and DHT. Scale bar corresponds to 10 μm.</p