RNA-Seq analysis of a Reciprocal Transplant experiment for two strains of Spodoptera frugiperda fed on rice or corn, in laboratory and natural populations
ABSTRACT: We wished to investigate if adaptation to host-plant diet is the basis of differentiation for two strains of Spodoptera frugiperda (Lepidoptera:Noctuidae). We performed reciprocal transplant experiments in laboratory conditions, feeding each strain (sf-C and sf-R) with artificial diet, corn plants or rice plants. RNA-Seq was performed on pooled 4th instar larvae from this experiment. We compared this transcriptional response with that of individual 4th instar larvae collected in corn and grass fields in Florida.
Project description:Rice, the world’s most important food crop, is attacked by multiple herbivores and pathogens.the rice striped stem borer (SSB) Chilo suppressalis is one of another most important rice insect pests. Here, we use Affymetrix Whole-Genome rice arrays to detect SSB infestation responsive genes. RNA samples from five damaged stems of SSB-challenged 24 h rice plants or five stems from unchallenged plants (for control samples) were used to array analysis. Two replicate biological experiments of SSB treatment rice arrays and one control samples array were peformed.
Project description:KMD is genetically engenered to be highly resistant to lepidopteran pests through expressing a synthetic cry1Ab gene and its parent non-transgenic rice is Xiushui 11.The developmental duration of BPH feeding on KMD2 was significantly delayed. And moreover, the fecundity of BPH was significantly lower when fed on Bt rice than on the non-Bt parental plants.To investigate unintended effects in KMD2 that causes changes in BPH performance, we performed microarray (GeneChip) analysis to compare the gene expression profiles between Bt rice and non-transgenic parental plants in response to BPH infestation. We used microarrays to detect Bt-independent variation, which might render Bt rice more defensive or less nutritious to BPH. For BPH treatment, 10 second-instar nymphs were infested onto each 30-day-old seedling. After 72 h, the BPH nymphs were carefully removed and rice shoots of both BPH-infested and non-infested plants were sampled for microarray analysis. There were four treatments: Xiushui 11-non infested, Xiushui 11-BPH infested, KMD2-non infested, KMD2-BPH infested, three biological replications.
Project description:In the present study molecular interactions between potato plants, Colorado potato beetle (CPB) larvae and Potato virus YNTN (PVYNTN) were investigated by analyzing gene expression in potato leaves. mRNA samples of secondary PVYNTN-infected (CPB_PVY) and healthy potato plants (CPB_H) cultivar Igor and of RNAi coi1-silenced (CPB_coi1) and non-transformed (CPB_NT) potato plants cultivar Desiree collected 24 h post CPB infestation and respective control non-infested samples (CONT_PVY, CONT_H, CONT_coi1, CONT_NT).
Project description:The green rice leafhopper (GRH), Nephotettix cincticeps Uhler, is a major insect pest of cultivated rice in temperate Asia. GRH2-near-isogenic line (NIL) TGRH11, GRH4-NIL (TGRH16) and GRH2/GRH4-pyramided line (PYL) TGRH29 were developed by introducing the GRH2 and GRH4 from indica rice (DV85). We identified GRH-inducible genes in respective rice lines. Furthermore, we compared the gene expression levels between NILs/PYL and control plants (T65). The gene expression changes in respective rice lines were detected by comparison between GRH-infested and pre-infested plants. Seedlings at the second-leaf stage were infested with 10 to 15 first- or second-instar nymphs in test tubes and shoots were collected at 30 h after GRH infestation. Detached-leaf blades at heading stage were infested with 10 to 15 first- or second-instar nymphs in test tubes and samples were collected at 30 h after GRH infestation. For each treatment, two biological replicates were performed.
Project description:Nematodes such as Steinernema carpocapsae are used as organic pesticides because of their ability to prey on live insects. They do so thanks to their symbiotic bacteria, that they release within the hemocoel of insects. In this study we wanted to study how Spodoptera frugiperda, a Lepidoptera pest of crops becoming invasive around the world, defend themselves against the nematodes. We infested S. frugiperda larvae with nematodes and dissected three tissues: the midgut, the fat body and the hemocytes at two time-points: 8 h and 15 h after infestation. We performed single-end RNA-seq on these samples to study the tissue specificity of S. fru response, as well as its dynamic.
Project description:Drosophila larvae were infected with Erwinia bacteria (Ecc15) by introducing concentrated bacterial pellet into the fly medium. The tracheae were dissected 24h later. Three genotypes of larvae were compared: wt (CantonS), RelE20 and PGRP-LA, each present in unchallenged and infected conditions. 3 independent repeats were performed.
Project description:The unsurpassed simplicity of the fruitfly’s airway epithelium, that is made of homogenous epithelial cells only, favours its use as a model to study general features and response characteristics of airway epithelia in general. All epithelial cells are able to launch an immune response as characterized by the expression of antimicrobial peptide genes. Infection induces a complex change in the expression profile of these epithelial cells. Outstanding are a priming of the immune system and the launch of a survival program, presumably to counteract infection induced apoptotic signals, which comprises the concurrent expression of known longevity genes such as dFoxo, and dThor. In regions of the airway epithelium with strong immune reactions, a complex remodelling of the airways can be observed, which is characterized by metaplasia and presumably also by hyperplasia of the affected epithelial cells. At the transcriptional level, this reorganization of the airway epithelium is mirrored by a recapitulation of genetic programs that are characteristic for early phases of airway development. Taken together, the response characteristics of the fly’s airway epithelium towards infections discloses features that are known from inflammatory diseases of the human lung, thus opening the opportunity to study fundamental aspects of these diseases in the fly. Keywords:infection, Erwinia c., third instar larva, airway epithelium, two-colour microarray Infection of the airway epithelium by the gram-negativ bacteria Erwinia carotovora. For the infection experiments third instar larvae of the GFP-reporter strain YW DD1 were used and only isolated when the whole epithelium of the airway epithelium showed GFP expression. Uninfected larvae were used as controls. In general, four replicates were performed including dye-swaps. A table of significantly-regulated genes from the SAM-output and GeneTraffic-output has been linked as a supplementary file at the foot of this record.
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.
Project description:In the present study we analyzed the function of one member of Drosophila CLPs namely Drosophila IDGF3 with a special focus on immunity. We found that Idgf3 mutants are homozygous viable, and have defects in hemolymph clotting, which is the earliest of Drosophila larvae response after injury. We could further demonstrate that IDGF3 contributes to fly immunity: idgf3 mutants show increased sensitivity to Gram-negative bacteria as well as increased mortality after nematode infections. IDGF3 overexpression leads to a hyper-coagulation phenotype in larvae and a decrease in viability of adult flies. Transcription profiling further confirmed that IDGF3 is involved in the activation of innate defense mechanisms and signal pathways connected to wound healing and regenerative processes. A large fraction of immune- and regenerative genes require IDGF3 for their induction, suggesting that ΓÇô similar to Chi3l1- IDGF3 is a key regulators of the epithelial response to injury and infection.