Project description:Muscle larva of a parasitic nematode Trichinella spp. lives a portion of muscle fiber transformed to a nurse cell (NC). The NC is formed from miss-differentiated muscle satellite cells which have fused with a parasite-invaded degenerating myofiber. Though originating from muscle cells, the NC is of non-muscular type.The NC is multinuclear and hypertrophic. Molecular mechanism of the NC development remains largely unknown. The microarray project was aimed at characterization of the NC transcriptome. The NCs were isolated by enzymatic digestion from infected mouse striated muscles. Murine C2C12 myogenic cell line (ATCC) was cultured in vitro. Differentiation of myoblasts into myotubes was carried out for 6 days in a high-glucose DMEM supplemented with 2% heat-inactivated horse serum, on the plates covered with laminin and collagen IV.The NC transcriptome was referred to the transcriptomes of C2C12 myoblasts and C2C12 myotubes in two sets of camparative expression microarray hybridization experiments, NC vs myoblasts and NC vs myotubes, respectively.
Project description:We present the first study to confirm the existence of DNA methylation in the parasitic nematode Trichinella spiralis, and we characterize the methylomes of the three life-cycle stages of this food-borne infectious human pathogen. We observe a drastic increase in DNA methylation during the transition from the new born to mature stage, and we further identify parasitism-related genes that show changes in DNA methylation status between life cycle stages. We also evaluated differential gene expression among the three life stages using Illumina HiSeq 2000 RNA-seq technology.
Project description:Trichinella spiralis is a highly destructive parasitic nematode that invades and destroys intestinal epithelial cells, injures many different tissues during its migratory phase, and occupies and transforms myotubes during the final phase of its life cycle. Mice deficient in the IL-1 family receptor for the DAMP, IL-33 (called ST2), display reduced intestinal Th2 responses and impaired mast cell activation. IL-33 was constitutively expressed in intestinal epithelial cells, where it became concentrated in nuclei within 2 days of infection. Nuclear localization was an innate response to infection that occurred in intestinal regions where worms were actively migrating. We isolated intestinal epithelial cells from uninfected mice (cytoplasmic IL-33) and mice at 2 days post-infection (nuclear IL-33) to compare global expression profiles. We used microarrays to characterize the global gene expression that occurs in intestinal epithelial cells following T. spiralis-induced nuclear translocation of IL-33.
Project description:Trichinellosis of human and other mammals was caused through the ingestion of the parasite,Trichinella spiralis,contaminated meat. It is a typical zoonotic disease that affects more than 10 million people world-wide. Parasites of Trichinella genus are unique intracellular pathogens. Adult Trichinella parasites directly release newborn larvae which invade striated muscle cells and causes diseases. In this study, we profiled the global transcriptome in the three developmental stages of T. spiralis. The transcriptomic analysis revealed the global gene expression patterns from newborn larval stage through muscle larval stage to adults. Thousands of genes with stage-specific transcriptional patterns were described and novel genes involving host-parasite interaction were identified. More than 45% of the protein-coding genes showed evidence of transcription from both sense and antisense strands which suggests the importance of RNA-mediated gene regulation in the parasite. This study presents a first deep analysis of the transcriptome of T. spiralis, providing insight information of the parasite biology.
Project description:Trichinella spiralis is a highly destructive parasitic nematode that invades and destroys intestinal epithelial cells, injures many different tissues during its migratory phase, and occupies and transforms myotubes during the final phase of its life cycle. Mice deficient in the IL-1 family receptor for the DAMP, IL-33 (called ST2), display reduced intestinal Th2 responses and impaired mast cell activation. IL-33 was constitutively expressed in intestinal epithelial cells, where it became concentrated in nuclei within 2 days of infection. Nuclear localization was an innate response to infection that occurred in intestinal regions where worms were actively migrating. We isolated intestinal epithelial cells from uninfected mice (cytoplasmic IL-33) and mice at 2 days post-infection (nuclear IL-33) to compare global expression profiles. We used microarrays to characterize the global gene expression that occurs in intestinal epithelial cells following T. spiralis-induced nuclear translocation of IL-33. Intestinal epithelial cells were isolated from Rag2-/- mice at day zero (uninfected) or two days post-infection with T. ispiralis for RNA extraction and hybridization on Affymetrix microarrays.
Project description:Publication of the genome from the clade I organism, Trichinella spiralis, has provided us an avenue to address more holistic problems in parasitology; namely the processes of adaptation and the evolution of parasitism. Parasitism among nematodes has evolved in multiple, independent events. Deciphering processes that drive species diversity and adaptation are keys to understanding parasitism and advancing control strategies. Studies have been put forth on morphological and physiological aspects of parasitism and adaptation in nematodes; however, data is now coming available to investigate adaptation, host switching and parasitism at the genomic level. Herein we compare proteomic data from the clade I parasite, Trichinella spiralis with data from Brugia malayi (clade III), Meloidogyne hapla and Meloidogyne incognita (clade IV), and free-living nematodes belonging to the genera Caenorhabditis and Pristionchus (clade V). We explore changes in protein family birth/death and expansion/reduction over the course of metazoan evolution using Homo sapiens, Drosophila melanogaster and Saccharomyces cerevisiae as outgroups for the phylum Nematoda. We further examine relationships between these changes and the ability and/or result of nematodes adapting to their environments. Data are consistent with gene loss occurring in conjunction with nematode specialization resulting from parasitic worms acclimating to well-defined, environmental niches. We observed evidence for independent, lateral gene transfer events involving conserved genes that may have played a role in the evolution of nematode parasitism. In general, parasitic nematodes gained proteins through duplication and lateral gene transfer, and lost proteins through random mutation and deletions. Data suggest independent acquisition rather than ancestral inheritance among the Nematoda followed by selective gene loss over evolutionary time. Data also show that parasitism and adaptation affected a broad range of proteins, especially those involved in sensory perception, metabolism, and transcription/translation. New protein gains with functions related to regulating transcription and translation, and protein family expansions with functions related to morphology and body development have occurred in association with parasitism. Further gains occurred as a result of lateral gene transfer and in particular, with the cyanase protein family In contrast, reductions and/or losses have occurred in protein families with functions related to metabolic process and signal transduction. Taking advantage of the independent occurrences of parasitism in nematodes, which enabled us to distinguish changes associated with parasitism from species specific niche adaptation, our study provides valuable insights into nematode parasitism at a proteome level using T. spiralis as a benchmark for early adaptation to or acquisition of parasitism.