Project description:Gut and rest of body tissue from fifth instar larvae which fed for three days a diet containing different doses of gossypol. Transcriptional profiling comparing gut and rest of body samples for three gossypol concentrations (0%, 0.016%-hormetic dose & 0.16%-detrimental dose). Hormesis is a biphasic biological response characterized by the stimulatory effect at relatively low amounts of chemical compounds otherwise known to be detrimental at higher concentrations. A hormetic response in larval growth rates has been observed in cotton-feeding insects in response to increasing concentrations of gossypol, a toxic metabolite found in the pigment glands of some Malvaceae plants. We investigated the developmental effect of gossypol in the cotton bollworm, Helicoverpa armigera, an important heliothine pest species, by exposing larvae to different doses of this metabolite in their diet. In addition, we sought to determine the underlying transcriptional responses to different gossypol doses. Larval weight gain, pupal weight and larval development time were measured in feeding experiments and a hormetic response was seen for the first two characters. On the basis of net larval weight gain responses to gossypol, three treatments, that is 0%, 0.016% and 0.16% gossypol , were selected for transcript profiling in the gut and the rest of the body in a two-color double reference design microarray experiment.
Project description:Gut and rest of body tissue from fifth instar larvae which fed for three days a diet containing different doses of gossypol. Transcriptional profiling comparing gut and rest of body samples for three gossypol concentrations (0%, 0.016%-hormetic dose & 0.16%-detrimental dose). Hormesis is a biphasic biological response characterized by the stimulatory effect at relatively low amounts of chemical compounds otherwise known to be detrimental at higher concentrations. A hormetic response in larval growth rates has been observed in cotton-feeding insects in response to increasing concentrations of gossypol, a toxic metabolite found in the pigment glands of some Malvaceae plants. We investigated the developmental effect of gossypol in the cotton bollworm, Helicoverpa armigera, an important heliothine pest species, by exposing larvae to different doses of this metabolite in their diet. In addition, we sought to determine the underlying transcriptional responses to different gossypol doses. Larval weight gain, pupal weight and larval development time were measured in feeding experiments and a hormetic response was seen for the first two characters. On the basis of net larval weight gain responses to gossypol, three treatments, that is 0%, 0.016% and 0.16% gossypol , were selected for transcript profiling in the gut and the rest of the body in a two-color double reference design microarray experiment. Two-color double reference design. Reference sample was the 0% (CT) gossypol condition (either Gut or Rest of Body) or one of two experimental conditions {0.016(T5) and 0.16%(T7)}. Biological replicates: 4 (10 individuals per replicate). 32 samples total.
Project description:The transcriptional response of H. armigera larvae was analyzed after feeding on gossypol supplemented diet, a toxic secondary metabolite produced in cotton plants, to detect potential detoxification enzymes possibly involved in detoxification of gossypol by H. armigera.
Project description:The transcriptional response of H. armigera larvae was analyzed after feeding on gossypol supplemented diet, a toxic secondary metabolite produced in cotton plants, to detect potential detoxification enzymes possibly involved in detoxification of gossypol by H. armigera. A one-color microarray-based gene expression analysis was performed with Cy3 labeled cRNA of gut and rest of the body of H. armigera larvae that fed on 0.016%, 0.16% gossypol and control diet. For each treatment and tissue four biological replicates were used.
Project description:Insect development requires genes to be expressed in strict spatiotemporal order. The degree of histone acetylation regulates insect development, via histone acetyltransferases (HATs) and histone deacetylases (HDACs). Although HDAC3 is required for early embryonic development, its functions in Helicoverpa armigera remain unclear. We treated H. armigera with HDAC3 siRNA and RGFP966, a specific inhibitor, examining how HDAC3 loss-of-function affects growth and development. HDAC3 siRNA and RGFP966 treatment increased mortality at each growth-stage and altered metamorphosis, hampering pupation and causing abnormal wing development, reduced egg production, and reduced hatching rate. RNA-seq analysis identified 2,788 differentially expressed genes (≥ two-fold change; P ≤ 0.05) between siHDAC3- and siNC-treated larvae. Kr-h1, were differentially expressed in HDAC3 knockdown larvae. Pathway enrichment analysis revealed significant enrichment of genes involved in the Hippo, MAPK, and Wnt signaling pathways following HDAC3 knockdown. Histone H3K9 acetylation was increased in H. armigera after siHDAC3 treatment. In conclusion, HDAC3-knockdown dysregulated 20-hydroxyecdysone hormone-related and apoptosis-related genes in H. armigera, affecting many basic processes, including cell cycle regulation, metabolism, and signal transduction. The Result showed that HDAC3 gene can serve as a potential target for fighting against Helicoverpa armigera.