Project description:Using microarray-based comparative genome hybridizations (mCGH), the genomic content of Wolbachia pipientis wMel from Drosophila melanogaster was compared to the Wolbachia from D. innubila (wInn), D. santomea (wSan), and three strains from D. simulans (wAu, wRi, wSim).
Project description:Using microarray-based comparative genome hybridizations (mCGH), the genomic content of Wolbachia pipientis wMel from Drosophila melanogaster was compared to the Wolbachia from D. innubila (wInn), D. santomea (wSan), and three strains from D. simulans (wAu, wRi, wSim). Cy3- and Cy5-labeled probes were synthesized from a pool of three distinct GenomiPhi amplifications to reduce bias. One flip-dye experiment (two hybridizations) was performed with each of three independent pools, yielding a total of six hybridizations/strain. With 4-8 printed replicates per slide this yielded 24-48 replicated spots per gene to compare across the study. Ratios were normalized using iterative log mode centering. The geometric mean ratio was calculated for all good spots in each flip-dye experiment.
Project description:Wolbachia, an endosymbiotic bacterium, is being investigated as a vector control agent in several insect species. Along with the well known classical reproductive parasitism Wolbachia employs against its host to spread within the population, it is emerging that the bacteria can protect the host against pathogens and reduced pathogen transmission. Anopheles mosquitoes, which transmit malaria, have never been found to harbour Wolbachia in nature, and despite numerous transinfection attempts, no stable line has been developed. However recently, two strains of Wolbachia, wAlbB from Aedes albopictus, and wRi from Drosophila simulans were cultured in Anopheles gambiae Sua5B cells. These cell lines provides an amenable system to study Wolbachia-Anopheles interaction in the absence of a stable transinfected line. It has been proposed that the compromised vector competence of Wolbachia infected insects is due to an up regulation of the basal immune state. We therefore completed a genome wide expression profile of Wolbachia infected Anopheles, assessing both wAlbB and wRi infected cells in parallel against uninfected Sua5B cells.
Project description:Wolbachia is a maternally transmitted bacterium that manipulates arthropod and nematode biology in myriad ways. The Wolbachia strain colonizing Drosophila melanogaster creates sperm-egg incompatibilities and protects its host against RNA viruses, making it a promising tool for vector control. Despite successful trials using Wolbachia-transfected mosquitoes for Dengue control, knowledge of how Wolbachia and viruses jointly affect insect biology remains limited. Using the Drosophila melanogaster model, transcriptomics and gene expression network analyses revealed pathways with altered expression and splicing due to Wolbachia colonization and virus infection. Included are metabolic pathways previously unknown to be important for Wolbachia-host interactions. Additionally, Wolbachia-colonized flies exhibit a dampened transcriptomic response to virus infection, consistent with early blocking of virus replication. Finally, using Drosophila genetics, we show Wolbachia and expression of nucleotide metabolism genes have interactive effects on virus replication. Understanding the mechanisms of pathogen blocking will contribute to the effective development of Wolbachia-mediated vector control programs.
Project description:Lymphatic filarial nematodes maintain a mutualistic association with the intracellular bacterium Wolbachia. Wolbachia populations expand following infection of the mammalian host, to support larval growth and development. Utilizing transcriptomic data from Brugia malayi over the first two weeks post-infection, we present an analysis of the biochemical pathways that are involved in Wolbachia population growth and regulation in support of larval development. In Wolbachia, we observe coordinated regulation of carbon metabolism with an alternating pattern of glycolysis and TCA cycle pathways reminiscent of the ‘Warburg effect’. Wolbachia's purine, pyrimidine and haem biosynthesis and Type IV secretion pathways are also upregulated and correlate with the upregulation of the nematode’s DNA replication pathway. In the nematode we observe up-regulation of the autophagy pathway, a key regulator of Wolbachia populations. These findings support a key role for nucleotide and haem provisioning from Wolbachia in support of the larval growth and development of its nematode host.
Project description:Wolbachia, an endosymbiotic bacterium, is being investigated as a vector control agent in several insect species. Along with the well known classical reproductive parasitism Wolbachia employs against its host to spread within the population, it is emerging that the bacteria can protect the host against pathogens and reduced pathogen transmission. Anopheles mosquitoes, which transmit malaria, have never been found to harbour Wolbachia in nature, and despite numerous transinfection attempts, no stable line has been developed. However recently, two strains of Wolbachia, wAlbB from Aedes albopictus, and wRi from Drosophila simulans were cultured in Anopheles gambiae Sua5B cells. These cell lines provides an amenable system to study Wolbachia-Anopheles interaction in the absence of a stable transinfected line. It has been proposed that the compromised vector competence of Wolbachia infected insects is due to an up regulation of the basal immune state. We therefore completed a genome wide expression profile of Wolbachia infected Anopheles, assessing both wAlbB and wRi infected cells in parallel against uninfected Sua5B cells. Two strains of Wolbachia, wRi from Drosophila simulans and wAlbB from Aedes albopictus were transfered into Anopheles gambiae Sua5B cells via the shell vial technique. After over 30 passages, these Wolbachia infected cells lines were then compared, in parallel, to the original uninfected Sua5B cells using Affymetrix microarrays.
Project description:Transcriptional profiling of Drosophila melanogaster larval testes with and without the wMel strain of Wolbachia and found that 296 genes had at least a 1.5 fold change [q-value (%)<5%] in transcript levels, with 167 genes up-regulated and 129 genes down-regulated when comparing Wolbachia-infected flies to uninfected ones. Differential expression of genes related to metabolism, immunity, reproduction and other functions were observed.
Project description:We characterized the miRNA composition of the nucleus and the cytoplasm of uninfected cells and compared it with the one of cells infected with the endosymbiotic bacterium Wolbachia strain wMelPop-CLA. We found an overall increase of small RNAs between 18 and 28 nucleotides in both cellular compartments in Wolbachia-infected cells and identified specific miRNAs induced and/or suppressed by the Wolbachia infection. We discuss the mechanisms that the cell may use to shuttle miRNAs between the cytoplasm and the nucleus. In addition, we identified piRNAs that changed their abundance in response to Wolbachia infection. The miRNAs and piRNAs identified in this study provide promising leads for investigations into the host-endosymbiont interactions and for better understanding of how Wolbachia manipulates the host miRNA machinery in order to facilitate its persistent replication in infected cells.