Project description:An analysis of the impact of infection by Buchnera aphidicola APS (isolated from Acyrthosiphon pisum strain LL01) on gene expression of S2 cells. All comparisons are made against a pool of RNA from S2 cells not exposed to B. aphidicola. B. aphidicola freshly isolated from the aphids, and data are collected at 1, 6 and 24 hours after exposure of S2 cells to the B. aphidicola preparation. Keywords: time course, Buchnera aphidicola APS, aphids, Drosophila melanogaster S2 cells
Project description:Buchnera aphidicola is an intracellular bacterial symbiont of aphids and maintains a small genome of only 600 kbps. Buchnera is thought to maintain only genes relevant to the symbiosis with its aphid host. Curiously, the Buchnera genome contains gene clusters coding for flagellum basal body structural proteins and for flagellum type III export machinery. These structures have been shown to be highly expressed and present in large numbers on Buchnera cells. No recognizable pathogenicity factors or secreted proteins have been identified in the Buchnera genome, and the relevance of this protein complex to the symbiosis is unknown. Here, we show isolation of Buchnera flagellum basal body proteins from the cellular membrane of Buchnera, confirming the enrichment of flagellum basal body proteins relative to other proteins in the Buchnera proteome. This will facilitate studies of the structure and function of the Buchnera flagellum structure, and its role in this model symbiosis.
Project description:An analysis of the impact of infection by Buchnera aphidicola APS (isolated from Acyrthosiphon pisum strain LL01) on gene expression of S2 cells. All comparisons are made against a pool of RNA from S2 cells not exposed to B. aphidicola. B. aphidicola freshly isolated from the aphids, and data are collected at 1, 6 and 24 hours after exposure of S2 cells to the B. aphidicola preparation. Keywords: time course, Buchnera aphidicola APS, aphids, Drosophila melanogaster S2 cells All comparisons are made against a pool of RNA from S2 cells not exposed to B. aphidicola. B. aphidicola freshly isolated from the aphids, and data are collected at 1, 6 and 24 hours after exposure of S2 cells to the B. aphidicola preparation.
Project description:Heat stress experiments imposed on Buchnera aphidicola within intact Schizaphis graminum hosts. NOTE: normalized values in GEO are NOT those derived from intensive analyses described in paper. Please see Wilcox et al. 2002 for description. Keywords = reduced bacterial genome, stress response Keywords: repeat sample
Project description:Heat stress experiments imposed on Buchnera aphidicola within intact Schizaphis graminum hosts. NOTE: normalized values in GEO are NOT those derived from intensive analyses described in paper. Please see Wilcox et al. 2002 for description. Keywords = reduced bacterial genome, stress response
Project description:Background: The best studied insect-symbiont system is that of aphids and their primary bacterial endosymbiont Buchnera aphidicola. Buchnera inhabits specialized host cells called bacteriocytes, provides nutrients to the aphid and has co-speciated with its aphid hosts for the past 150 million years. We have used a single microarray to examine gene expression in the pea aphid, Acyrthosiphon pisum, and its resident Buchnera. Very little is known of gene expression in aphids, few studies have examined gene expression in Buchnera, and no study has examined simultaneously the expression profiles of a host and its symbiont. Expression profiling of aphids, in studies such as this, will be critical for assigning newly discovered A. pisum genes to functional roles. In particular, because aphids possess many genes that are absent from Drosophila and other holometabolous insect taxa, aphid genome annotation efforts cannot rely entirely on homology to the best-studied insect systems. Development of this dual-genome array represents a first attempt to characterize gene expression in this emerging model system. Results: We chose to examine heat shock response because it has been well characterized both in Buchnera and in other insect species. Our results from the Buchnera of A. pisum show responses for the same gene set as an earlier study of heat shock response in Buchnera for the host aphid Schizaphis graminum. Additionally, analyses of aphid transcripts showed the expected response for homologs of known heat shock genes as well as responses for several genes with unknown functional roles. Conclusions: We examined gene expression under heat shock of an insect and its bacterial symbiont in a single assay using a dual-genome microarray. Further, our results indicate that microarrays are a useful tool for inferring functional roles of genes in A. pisum and other insects and suggest that the pea aphid genome may contain many gene paralogs that are differentially regulated. Keywords: Stress response