Project description:Strigomonas culicis is a kinetoplastid parasite of insects that maintains a mutualistic association with an intracellular symbiotic bacterium, that is highly integrated into the protozoa metabolism: it furnishes essential compounds and divides in synchrony with the nuclear host. The protozoa, conversely, can be rid of the endosymbiont, producing a cured cell line, which presents a diminished ability to colonize the insect host. This obligatory association can represent an intermediate step of the evolution towards the formation of a organelle, therefore representing an interesting model to understand the symbiogenesis theory. Here, we used shotgun proteomics to compare the S. culicis endosymbiont-containing and aposymbiotic strains, revealing a total of 11,305 peptides, and up to 2,213 proteins (2,029 and 1,452 for wild and aposymbiotic, respectively). Gene ontology associated to comparative analysis between both strains revealed that the biological processes most affected by the elimination of the symbiont were the amino acid metabolism, as well as protein synthesis and folding. This large-scale comparison of the protein expression in S. culicis marks a step forward in the comprehension of the role of endosymbiotic bacterium in monoxenic trypanosomatid biology, particularly because these organisms have a polycistronic open reading frame organization and post-transcriptional gene regulation.
Project description:Abstract: The Kinetoplastida (Euglenozoa) are unicellular flagellates that include the trypanosomatid parasites, most notably Trypanosoma brucei, T.cruzi and Leishmania spp. These organisms cause substantial mortality and morbidity in humans and their livestock worldwide as the causative agents of African sleeping sickness, Chagas disease and leishmaniasis respectively. Draft genome sequences are available for several species of both Trypanosoma and Leishmania. Bodo saltans is a free-living heterotroph found worldwide in freshwater and marine habitats, and it is among the closest bodonid relatives of the trypanosomatids. The purpose of a B. saltans genome sequence is to provide an 'out-group' for comparative genomic analysis of the trypanosomatid parasites. It will provide a model of the ancestral trypanosomatid to distinguish those derived parts of the parasite genomes (i.e., unique trypanosomatid adaptations) from those which are a legacy of the free-living ancestor. To aid annotation of the B.saltans genome sequence, total genomic RNA was extracted on four occasions from the total cellular mass of 160ml of B.saltans cell culture, for the purposes of transcription profiling by high throughput sequencing. Cells were unmodified. B.saltans cells were grown in water at 4oC. Total genomic RNA was extracted from a cell pellet using TRIZOL reagent and ethanol precipitated. Poly A+ mRNA was purified from total RNA using oligo dT dyna bead selection and libraries were created using the Illumina RNA-seq protocol. The samples were sequenced on an Illumina HiSeq 2000. 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:We report the application of CAGE (Cap Analysis of Gene Expression) on collections of Daphnia pulex individuals representing three major developmental states. This submission comes from a project of Michael Lynch and was funded by a grant from the National Institutes of Health entitled 'Population Genomics of Daphnia pulex' (Project Number: 1R01GM101672-01A1).