Project description:Using Illumina platform, deep sequencing of 12 small RNA libraries was performed from Helicoverpa armigera larvae fed on artificial diet (AD) or recombinant Capsicum annuum PI-7 (rCanPI-7) incorporated diet at various time intervals (0.5, 2, 6, 12, 24, and 48h). Several candidate miRNAs (conserved and novel) were differentially expressed in rCanPI-7 fed larvae as compared to the larvae fed on AD. The investigation revealed potential roles of miRNAs in H. armigera protease gene regulation.
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:Insects adapt to plant protease inhibitors (PIs) present in their diet by differentially regulating multiple digestive proteases. However, mechanisms regulating protease gene expression in insects are largely enigmatic. Ingestion of Capsicum annuum protease inhibitor-7 (CanPI-7) arrests growth and development of Helicoverpa armigera (Lepidoptera: noctuidae). Using de novo RNA sequencing and proteomic analysis, we examined the response of H. armigera larvae fed on recombinant C. annuum PI (CanPI) at different time intervals. Here, we present evidence supporting a dynamic transition in H. armigera protease expression upon CanPI feeding with general down-regulation of protease genes at early time points (0.5 to 6 h) and significant up-regulation of specific trypsin, chymotrypsin and aminopeptidase genes at later time points (12 to 48 h).
