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: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:Laodelphax striatellus is naturally infected with the Wolbachia strain wStri, which significantly increase the fecundity of its host. Wolbachia-infected females produce 30%–40% more eggs than Wolbachia-uninfected females. MicroRNAs (miRNAs) are a class of endogenous non-coding small RNAs that play critical roles in the regulation of gene expression at post-transcriptional level. Here we report the differentially expressed miRNAs between Wolbachia-infected and Wolbachia-uninfected strains of L. striatellus ovaries. Our data may be helpful to explore the molecular mechanisms by which Wolbachia increase the fecundity of Laodelphax striatellus.
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:The Drosophila-Wolbachia system is being used to study the molecular nature of the interactions between a host and a symbiont. This system offers a unique opportunity for such a study since the Drosophila genome sequence is available, several Wolbachi genomes will also be available soon and there are at least three known Wolbachia strains infecting Drosophila: a) mod+ strain that induces cytoplasmic incompatibility, b) mod- strain that cannot induce cytoplasmic incompatibility, and c) popcorn strain, a virulent strain which reduces in half the adult lifespan of Drosophila due to its massive proliferation in adult brain. The Drosophila-Wolbachia interaction manifests itself in 3 main ways; first, destruction of the CNS in infected adults, second, induction of some kind of modification or imprinting in the male germ-line resulting in an early failure in embryonic development, (cytoplasmic incompatability (CI)) and third, modification of the female germ-line resulting in resistance to modified sperm. We are interested in identifying Drosophila genes with changes in expression due to Wolbachia infection. We have generated a series of isogenic fly lines (those being used in the IGF P-element project) which we have infected with Wolbachia strains, infection is readily cured by growth on medium containing tetracycline. Thus, we have equivalent genetic background with and without the parasite. We have tested all of the transgenic lines for the level of CI and find strain-specific levels ranging from 0-50%. We also have a strain of D. simulans that shows over 95% CI. Plan: For our initial experiments we wish to make 4 comparisons, in all cases 2 day old males will be collected and for each comparison we will isolate 3 independent biological replicates: Melanogaster no CI [tet] x Melanogaster no CI [+wol] Melanogaster high CI [tet] x Melanogaster high CI [+wol] We will therefore identify genes with changed expression levels in the male upon Wolbachia infection by comparing the melanogaster strains with high or no CI in the presence of tetracycline and Wolbachia. We also hope to identify similar genes in simulans (where we expect the magnitude of the effect to be larger), differences between melanogaster and simulans are controlled for in the mel v sim comparison.
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:We used microarray analysis to screen the Drosophila genome for effects of Wolbachia infection on transcript levels in wildtype adult immature ovaries. Keywords: Comparative expression analysis of infection effect