Project description:We report the application of next generation RNA sequencing to analyze the transcriptional response of Drosophila adult flies to infection by the insect pathogenic nematodes Heterorhabditis bacteriophora and their mutualistic bacteria Photorhabdus luminescens, either separately or together. We find that Heterorhabditis and Photorhabdus differentially modulate a large number of genes, many of which participate in metabolic functions, stress responses, repression of gene transcription and neuronal activities. We have also identified Drosophila genes with potential role in nematode recognition and others with putative anti-nematode properties. These findings generate novel insights into how the host immune function is shaped to respond against nematode parasites and their associated bacteria. Transcriptional profiles of Drosophila wild-type adult flies infected with Heterorhabditis bacteriophora carrying or lacking Photorhabdus or the bacteria alone were generated at 12 and 30 hours post infection using Illumina deep sequencing technology.
Project description:We report the application of next generation RNA sequencing to analyze the transcriptional response of Drosophila adult flies to infection by the insect pathogenic nematodes Heterorhabditis bacteriophora and their mutualistic bacteria Photorhabdus luminescens, either separately or together. We find that Heterorhabditis and Photorhabdus differentially modulate a large number of genes, many of which participate in metabolic functions, stress responses, repression of gene transcription and neuronal activities. We have also identified Drosophila genes with potential role in nematode recognition and others with putative anti-nematode properties. These findings generate novel insights into how the host immune function is shaped to respond against nematode parasites and their associated bacteria.
Project description:Entomopathogenic nematodes (EPNs) of the genera Heterorhabditis are obligate and lethal insect parasites. In recent years they have been used increasingly as biological control agents. These EPNs are symbiotically associated with bacteria of the genera Photorhabdus. The bacterial symbionts are essential to kill the host (within 24-48 hours) and digest its tissues to provide nutrients for themselves as well for expanding nematodes. Drosophila larvae are suitable insect hosts and part of the tripartite model system we used before to show the importance of haemolymph clotting and eicosanoids during the infection. We used the well-established tripartite model (Drosophila, nematodes, bacteria), DNA chips and bioinformatic tools to compare gene expression in non-infected and infected fly larvae. We focused on the early time point of nematode infection and therefore infected Drosophila larvae using H. bacteriophora harbouring GFP-labelled P. luminescens bacteria. Infected (GFP positive) larvae were collected 6 hours after infection.
