Project description:A custom microarray, based on deep transcriptome sequencing ((GEO accession number: GSE34418), was used to simultaneously investigate expression of over 24,000 Helicoverpa zea insect transcripts and 134 H. armigera nucleopolyhedrovirus (HearNPV) genes throughout the infection process at 0, 12, 24 and 48 hours post infection
Project description:A custom microarray, based on deep transcriptome sequencing ((GEO accession number: GSE34418), was used to simultaneously investigate expression of over 24,000 Helicoverpa zea insect transcripts and 134 H. armigera nucleopolyhedrovirus (HearNPV) genes throughout the infection process at 0, 12, 24 and 48 hours post infection A cutom 8x60,000 SurePrint Agilent expression slide (Agilent, Santa Clara, CA) was used to analyzed eight samples, including biological replicates of HaSNPV-infected cultures at 0, 12, 24 and 48 hpi.The microarray probes included probes for 27,400 H. zea sequences that were validated previously (Nguyen et al., 2012. PLOS ONE, 7(5), e36324) and all 134 H. armigera single-capsid nucleopolyhedrovirus (HearNPV) genes (Accession: NC_002654).
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:One of important insect defense mechanisms is melanization, which are mediated by clip domain serine protease (cSP) cascades and regulated by Serpins. In vitro, activation of melanization can efficiently kill Nucleopolyhedrovirus (NPV). However, quantitative proteomics revealed that the infection of NPV in cotton bollworm Helicoverpa armigera suppressed protein levels of melanization components in the host hemolymph. It also reduced the prophenoloxidase (PPO) activity. In contrast, Serpin-9 and -5 were sequentially up-regulated. Serpin-5 and -9 induced by NPV infection play important roles in regulate host melanization by directly inhibiting their target proteases cSP4 and cSP6 respectively. Furthermore, Serpin-5 or -9 depleted insects exhibited high PO activities and show resistance to NPV infection. Together, our results characterized melanization cascade in H. armigera, and suggests that natural insect virus NPV has evolved a distinct strategy to suppress host immune system. This finding may be exploited to design more potent viruses against agricultural pests.