Project description:This SuperSeries is composed of the following subset Series: GSE34344: Transcriptional analysis of physiological pathways in a generalist herbivore: responses to different host plants and plant structures by the cotton bollworm (CBW) Helicoverpa armigera [CottonStructures] GSE34346: Transcriptional analysis of physiological pathways in a generalist herbivore: responses to different host plants and plant structures by the cotton bollworm (CBW) Helicoverpa armigera [DifferentHost] Refer to individual Series
Project description:Cotton seeds (Gossypium hirsutum cv. CCRI12) were grown in a growth chamber under 29/25°C temperature and a 16:8 h light:dark cycle, and water was added every two days. All plants were used in experiments at the 6-7 fully expanded true leaf stage, which occurred 5-6 weeks after sowing. Cotton bollworm (CBW; Helicoverpa armigera) larvae were reared on an artificial diet and maintained at 27 ± 2°C, 75 ± 10% relative humidity, and 14:10 h light:dark in the laboratory. For insect treatment, seven H. armigera larvae (third instars) were placed on a group of three plants, which were kept within plastic bags (30 × 40 cm), until time of harvest, with samples for each time point maintained separately. Undamaged plants maintained under the same conditions were used as controls. Cotton leaves from control plants and plants exposed to H. armigera were harvested at 6 h, 12 h, 24 h, and 48 h after onset of herbivory. For each treatment group and time point, cotton leaves were harvested from the three plants per treatment group and flash frozen in liquid nitrogen. For each time point, three replicate treatments and controls were performed. For insect treatment, seven H. armigera larvae (third instars) were placed on a group of three plants, which were kept within plastic bags (30 × 40 cm), until time of harvest, with samples for each time point maintained separately. Undamaged plants maintained under the same conditions were used as controls. Cotton leaves from control plants and plants exposed to H. armigera were harvested at 6 h, 12 h, 24 h, and 48 h after onset of herbivory. For each treatment group and time point, cotton leaves were harvested from the three plants per treatment group and flash frozen in liquid nitrogen. For each time point, three replicate treatments and controls were performed.
Project description:Cotton seeds (Gossypium hirsutum cv. CCRI12) were grown in a growth chamber under 29/25°C temperature and a 16:8 h light:dark cycle, and water was added every two days. All plants were used in experiments at the 6-7 fully expanded true leaf stage, which occurred 5-6 weeks after sowing. Cotton bollworm (CBW; Helicoverpa armigera) larvae were reared on an artificial diet and maintained at 27 ± 2°C, 75 ± 10% relative humidity, and 14:10 h light:dark in the laboratory. For insect treatment, seven H. armigera larvae (third instars) were placed on a group of three plants, which were kept within plastic bags (30 Ã? 40 cm), until time of harvest, with samples for each time point maintained separately. Undamaged plants maintained under the same conditions were used as controls. Cotton leaves from control plants and plants exposed to H. armigera were harvested at 6 h, 12 h, 24 h, and 48 h after onset of herbivory. For each treatment group and time point, cotton leaves were harvested from the three plants per treatment group and flash frozen in liquid nitrogen. For each time point, three replicate treatments and controls were performed. For insect treatment, seven H. armigera larvae (third instars) were placed on a group of three plants, which were kept within plastic bags (30 Ã? 40 cm), until time of harvest, with samples for each time point maintained separately. Undamaged plants maintained under the same conditions were used as controls. Cotton leaves from control plants and plants exposed to H. armigera were harvested at 6 h, 12 h, 24 h, and 48 h after onset of herbivory. For each treatment group and time point, cotton leaves were harvested from the three plants per treatment group and flash frozen in liquid nitrogen. For each time point, three replicate treatments and controls were performed. In this study we present dynamic transcriptome analysis and volatile profiling of cotton plants fed upon by larvae of a leaf-chewing herbivore CBW. Plant transcriptomic changes induced by CBW were analyzed using Affymetrixâ??s Cotton GeneChips. Samples from a time course of six hour to 48 hours following onset of CBW feeding were analyzed to identify target genes and key pathways involved in the activation of herbivory-induced indirect defense and to explore genetic basis of such defense. In addition, we monitored the accumulation of VOCs, which represent changes in cotton plant phenotype, following CBW infestation.
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.
Project description:Transcriptional profiling comparing gut tissue from fifth instar larvae exposed to five different diets, namely cotton fruit or boll (B), cotton flower bud or square (SQ), cotton leaf (L), pinto bean-based artificial diet (PB) and wheat-based artificial Lepidoptera diet (BIO). The generalist lepidopteran herbivore Helicoverpa armigera can consume host plants in more than 40 plant families, and often utilizes several different tissues on the same plant. It is believed that generalists owe their success to the deployment of various members of multigene families of detoxicative and digestive enzymes, a strategy that may also be responsible for rapid evolution of insecticide resistance. However studies of generalist adaptations have been limited to specific genes or gene families, and an overview of how these adaptations are orchestrated at the transcriptional level is lacking. To investigate the previously-shown CBW preferences for different cotton plant structures, we measured net weight gain of larvae that fed on different cotton organs and compared the transcript profiles of larval guts in response to these organs and towards two different artificial diets commonly used for laboratory rearing of this species, using a two-color alternating loop design microarray experiment.