Project description:The Helicoverpa armigera single-capsid nucleopolyhedrovirus (HaSNPV) can be propagated using H. zea insect cell cultures, for use as a biopesticide against Heliothine agricultural pests.This study sequenced, assembled and functionally annotated 29,586 transcript sequences from cultured H. zea cells using Illumina 100 bps and paired-end transcriptome sequencing (RNA-seq). From these sequences, a genome-scale microarray platform was constructed and validated for effective expression analysis of H. zea genes. This array also included probes for all HaSNPV genes, thereby allowing virus and host gene changes to be monitored simultaneously.
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:The Helicoverpa armigera single-capsid nucleopolyhedrovirus (HaSNPV) can be propagated using H. zea insect cell cultures, for use as a biopesticide against Heliothine agricultural pests.This study sequenced, assembled and functionally annotated 29,586 transcript sequences from cultured H. zea cells using Illumina 100 bps and paired-end transcriptome sequencing (RNA-seq). From these sequences, a genome-scale microarray platform was constructed and validated for effective expression analysis of H. zea genes. This array also included probes for all HaSNPV genes, thereby allowing virus and host gene changes to be monitored simultaneously. A 4x180,000 SurePrint Agilent expression array (Agilent, Santa Clara, CA) was employed so that a high number of probes can be included to test all 29,586 assembled H. zea sequences and to eventually select a best probe for each transcript. Two biological replicates for uninfected H. zea cells and two other biological replicates for infected samples at 18 hours post infection were analyzed. Six Agilent 60-mer oligonucleotide probes were designed by eArray (Agilent) for each transcript, in which each orientation had three probes randomly distributed across the sequences. Probes that had potential cross-hybridization (Xhyb) were removed. The final probe set for H. zea sequences included 153,583 probes. In addition, probes for all 135 H.armigera single-capsid nucleopolyhedrovirus (HaSNPV) genes were added to investigate host-virus interaction in culture.
Project description:Sterols are essential nutrients for insects because, in contrast to mammals, no insect (or arthropod for that matter) can synthesize sterols de novo. Cholesterol is the most common sterol in insects, but it is not found in plants in large quantities; plant-feeding insects typically generate their cholesterol by metabolizing phytosterols. However, different plants species can contain different types of phytosterols, and some phytosterols are not readily converted to cholesterol. In this study we examined, using artificial diets containing single sterols, how typical (cholesterol and stigmasterol) and atypical (cholestanol and cholestanone) sterols/steroids affect the performance of a generalist caterpillar (Helicoverpa zea), restricting this analysis to midgut tissue because this is where sterol/steroid absorption occurs, and the midgut is the putative site of dietary sterol/steroid metabolism. In general, H. zea performed best on the cholesterol and stigmasterol treatments; performance was reduced on cholestanol, and was very poor on cholestanone. We compared the transcript profiles of larval guts in response to differentially suitable sterols, using the optimal sterol, cholesterol, as a control, using a two-color reference design microarray experiment. Midgut gene expression patterns differed between the treatments; relative to cholesterol, differences were lowest on the stigmasterol treatment, intermediate on the cholestanol treatment, and greatest on the cholestanone treatment. Transcriptional profiling comparing Helicoverpa zea gut tissue from third instar larvae exposed to four different dietary sterols, namely Cholesterol (CON), Cholestanol (ChStanol), Cholestan-3-one (Ch3one) and Stigmasterol (Stigma). Two-color reference design. Biological replicates: 4 (5 individuals per replicate). 12 samples total.
