Project description:The genus Strongyloides spp. include important human parasites. There is also a well studied rodent model, S. ratti. Uniquely among parasitic nematodes, the Strongyloides life-cycle includes both a parasitic female stage and a genetically identical free-living female stage. Differences between these two female forms must be epigenetic, presumably controlled by altered transcription and translation. This is a project to compare the proteome and transcriptome of the parasitic and free-living females of S. ratti. From this we will define the genes and gene products of the parasitic female stage. This approach exploits the currently advanced S. ratti genome sequencing project. This work will give an understanding of the molecular basis of nematode parasitism, and so define new potential drug targets. This data is part of a pre-publication release. For information on the proper use of pre-publication data shared by the Wellcome Trust Sanger Institute (including details of any publication moratoria), please see http://www.sanger.ac.uk/datasharing/
Project description:Strongyloides ratti is a common gastro-intestinal parasite of the rat. The adult parasites are female only, about 2mm long and live in the mucosa of the small intestine. These parasites produce eggs that pass out of the host in its faeces. In the environment infective larval stages develop either directly or after a facultative sexual free-living adult generation. Infective larvae infect hosts by skin penetration.S. ratti is the laboratory analogue of the parasite of humans, S. stercoralis. S. stercoralis is a wide-spread parasite of humans, occurring principally in the tropics and sub-tropics: some 100-200 million people are infected worldwide. Infection of immunosuppressed individuals can result in disseminated strongyloidiasis, in which worms occur throughout the body. This can be fatal unless anti-Strongyloides therapy is given. Other species of Strongyloides parasitise a wide range of vertebrates. As part of the Strongyloides ratti genome project we are profiling the transcriptome of the parasite across its life cycle using RNA-Seq.. This data is part of a pre-publication release. For information on the proper use of pre-publication data shared by the Wellcome Trust Sanger Institute (including details of any publication moratoria), please see http://www.sanger.ac.uk/datasharing/
Project description:Strongyloides ratti is a parasitic nematode of rats and a laboratory model for nematode infection more generally. The response of two lines of S. ratti were compared in contrasting immunological environments: (i) day 5 post infection (p.i.) in naive rats; (ii) day 12 p.i. in naive rats; day 5 p.i. in rats previously immunised with 10 iL3s; and day 12 p.i. in rats previously immunised with 10 iL3s. The gene expression response of parasitic females were assayed using cDNA microarrays. Large numbers of responding genes were found (but with modest fold changes) and clusters of co-expressed genes identified with differences observed between worms taken from naive and previously exposed hosts and from the two time points.
Project description:Strongyloides ratti is a parasitic nematode of rats and a laboratory model for nematode infection more generally. The aim of this experiment was to determine the gene expression response of parasitic females to abiotic factors in its environment ex vivo that may be relevant to its natural environment in the gut in vivo. Thus, we used cDNA arrays to assay transcriptional responses to high and low salt, to RPMI versus PBS media and to 37C versus 40C. A moderate number of gene expression changes were observed.
Project description:Strongyloides ratti is a parasitic nematode of rats and a laboratory model for nematode infection more generally. Selected lines were generated over the course of 20 - 30 generations such that eggs were harvested either at the beginning or towards the end of an infection, termed 'fast' and 'slow' lines, respectively. Phenotypic differences in these lines in their fecundity and response to host immunity were observed. The gene expression response of these lines in both permissive and restrictive immune environments were assayed using cDNA microarrays. Large numbers of responding genes were found (but with modest fold changes) and clusters of co-expressed genes identified. Genes exhibiting female-biased expression responded to host immunity, consistent with increased investment into transmission in restrictive immune environments.
Project description:Project to produce a reference quality genome for Strongyloides ratti, a common gastro-intestinal parasite of the rat and laboratory analogue of the parasite of humans, S. stercoralis
Project description:In previous studies we have shown that the two adult females morphs of S. ratti have very different lifespans. This experiment was designed to try to identify differentially expressed genes in these two adult morphs that may account for these differing lifespans. The genes expressed by S. ratti parasitic females at day 6 p.i. were compared to the genes expressed by S. ratti free living females at 3 days 19 degrees C. This comparison was done using a microarray chip that is spotted with PCR fragments from the libraries that were generated from parasitic females extracted at day 6 and day 15 p.i., and a microarray chip that is spotted with PCR fragments from the libraries that were generated from free-living larval stages L1, L2 and infective L3s and from free-living males and females.