Project description:Nitric oxide (NO) is a gaseous intercellular signaling molecule that also plays a role in host-parasite relations. NO acts rapidly, either via regulation of soluble guanylate cyclase, or by direct interactions with enzymes and other proteins, and has also been shown to have effects on gene expression. Here, we use SAGE (Serial Analysis of Gene Expression) to identify NO-responsive changes in gene expression in Schistosoma mansoni following a 3 hour exposure to sodium nitroprusside, an NO donor. Overall, these results indicate that NO does not rapidly induce large-scale changes in schistosome gene expression, but that expression of particular genes of interest appear to respond to NO. Keywords: Schistosoma, SAGE, NOS, nitric oxide, gene expression
Project description:Protein variation in blood-dwelling schistosome worms generated by differential splicing of micro-exon gene transcripts. The infective schistosome cercaria develops from an undifferentiated germ ball within the daughter sporocyst in the molluscan host, during which considerable morphological development and synthesis of proteins essential for infection occurs. The free-living, non-feeding cercaria is notable for its swimming and host location behaviour. On contact with host skin it rapidly penetrates, replaces its tegument surface membranes, and begins body remodelling, before crossing the dermis to exit the skin via a blood vessel. Such a ‘violent’ transition from snail to fresh water to mammalian host should be accompanied by remarkable changes in the patterns of gene expression. All gene models from version E of the S. mansoni genome (www.GeneDB.org) were incorporated into a 350K feature Roche-NimbleGen, high-density oligonucleotide array. From a map-ordered list, every 13th 50mer was chosen as a probe. Double-stranded cDNA from three biological replicates each of germ balls, cercariae, and day 3 schistosomula was hybridised to the array without amplification. Statistical analysis was carried out using programmes from the Bioconductor suite (Gentleman et al. 2004 Genome Biol 5(10):R80). More than 1000 loci were shown to be differentially expressed in each of the comparisons between the three life cycle stages. Gene ontology (GO) analysis was then carried out to discover the categories enriched in each stage. In addition custom categories based on biological function (e.g. stress response) or parasite tissue (e.g. tegument) were analysed.
Project description:The schistosome homolog of hnf4 is involved in parasite blood feeding and stem cell biology. In order to understand the function of hnf4, we performed RNAseq on either control(RNAi) or hnf4(RNAi) parasites to see the transcriptional consequences of hnf4 RNAi
Project description:Protein variation in blood-dwelling schistosome worms generated by differential splicing of micro-exon gene transcripts. The infective schistosome cercaria develops from an undifferentiated germ ball within the daughter sporocyst in the molluscan host, during which considerable morphological development and synthesis of proteins essential for infection occurs. The free-living, non-feeding cercaria is notable for its swimming and host location behaviour. On contact with host skin it rapidly penetrates, replaces its tegument surface membranes, and begins body remodelling, before crossing the dermis to exit the skin via a blood vessel. Such a ‘violent’ transition from snail to fresh water to mammalian host should be accompanied by remarkable changes in the patterns of gene expression. All gene models from version E of the S. mansoni genome (www.GeneDB.org) were incorporated into a 350K feature Roche-NimbleGen, high-density oligonucleotide array. From a map-ordered list, every 13th 50mer was chosen as a probe. Double-stranded cDNA from three biological replicates each of germ balls, cercariae, and day 3 schistosomula was hybridised to the array without amplification. Statistical analysis was carried out using programmes from the Bioconductor suite (Gentleman et al. 2004 Genome Biol 5(10):R80). More than 1000 loci were shown to be differentially expressed in each of the comparisons between the three life cycle stages. Gene ontology (GO) analysis was then carried out to discover the categories enriched in each stage. In addition custom categories based on biological function (e.g. stress response) or parasite tissue (e.g. tegument) were analysed. Three biological replicates each of germ balls, cercariae, day 3 in vitro cultured schistosomula, and eggs were used. No technical replicates were included. This is the first genome-wide microarray platform for S. mansoni. It was used to investigate the gene expression patterns of the above lifecycle stages. The first three are the stages before, during and after penetration of mammalian host skin.
Project description:Schistosomes infect more than 200 million of the world's poorest people. These parasites live in the vasculature, producing eggs that spur a variety of chronic, potentially life-threatening, pathologies exacerbated by the long lifespan of schistosomes, that can thrive in the host for decades. How schistosomes maintain their longevity in this immunologically hostile environment is unknown. Here, we demonstrate that somatic stem cells in Schistosoma mansoni are biased towards generating a population of cells expressing factors associated exclusively with the schistosome host-parasite interface, a structure called the tegument. We show cells expressing these tegumental factors are short-lived and rapidly turned over. We suggest that stem cell-driven renewal of this tegumental lineage represents an important strategy for parasite survival in the context of the host vasculature.
Project description:Nitric oxide (NO) is a gaseous intercellular signaling molecule that also plays a role in host-parasite relations. NO acts rapidly, either via regulation of soluble guanylate cyclase, or by direct interactions with enzymes and other proteins, and has also been shown to have effects on gene expression. Here, we use SAGE (Serial Analysis of Gene Expression) to identify NO-responsive changes in gene expression in Schistosoma mansoni following a 3 hour exposure to sodium nitroprusside, an NO donor. Overall, these results indicate that NO does not rapidly induce large-scale changes in schistosome gene expression, but that expression of particular genes of interest appear to respond to NO. Keywords: Schistosoma, SAGE, NOS, nitric oxide, gene expression Adult S. mansoni perfused from infected Swiss-Webster female mice (obtained from the NIAID Schistosomiasis Resource Center) 42-49 days postinfection were maintained in culture (RPMI medium) overnight and then exposed for 3 hours to either 1 mM sodium nitroprusside (SNP), a well-characterized NO donor, or to RPMI alone. Worms remained viable and motile following treatment. Total RNA was extracted with Trizol (Invitrogen) and treated with DNAse 1 (Ambion) to remove contaminating genomic DNA, and Long-SAGE libraries constructed.
Project description:Suppression subtractive hybridization(SSH) libraries of Schistosoma japanicum female and male worms were constructed by using Clontech PCR-selectTM cDNA subtraction kit. S.japonicum cDNA microarrays were fabricated using female and male cDNA clones originating from SSH libraries. female-associated and Male-associated differentially expressed gene clones were obtained, Analysis of gender-associated differentially expressed genes helps to determine which genes are important to sexual maturation of schistosome and better understand schistosome biology and host-parasite relationship, facilitate the discovery of novel gene products that could represent targets for the development of new drugs and vaccines to control chitosomiasis. Keywords: gender-associated