Project description:The aim of this experiment was to compare the transciptome of the fall armyworm (Spodoptera frugiperda) strain SUS (a laboratory insecticide-susceptible standard) with organophosphate (OP) and pyrethroid (PYR) resistant strains were collected in cornfields located in Minas Gerais and Mato Grosso States, Brazil, in 2008 and maintained in the laboratory under selection with chlorpyrifos (at increasing discriminating doses from 100 up to 400 µg of insecticide/g of insect in a topical bioassay) or lambda-cyhalothrin (from 8.4 up to 27 µg of insecticide/g of insect) respectively The custom microarray used in this study was designed using the Agilent eArray platform (Agilent Technologies). A SurePrint HD (8×15k) expression array was designed using the base composition and the best probe methodologies to design sense orientation 60-mer probes with a 3′ bias. The FAW EST database (SPODOBASE) was used as the reference transcriptome (Negre, Hotelier et al. 2006). These sequences are derived from 8 cDNA libraries as follows: Sf1F: Fat body, Sf1H: Hemocyte, Sf1M: Midgut, Sf1P: Pool of various tissues, Sf2H: Immune Challenged hemocytes, Sf2L: Sf21 Cell lines sequences, Sf2M: Xenobiotic Induced Midgut and Sf9L: Sf9 cell lines sequences. All assembled contigs and singlets were kindly sent by the website maintainers. The BLAST2GO software v.2.3.1 (http://www.blast2go.org) was used to annotate the EST database. 60-mer probes were designed for all 7,552 assembled contigs and 5,519 annotated singlets (BlastX), totaling 13,071 sequences. For contigs encoding detoxification enzymes (P450s, GSTs and CEs) three probes were designed. Additional probe groups for 15 control genes were also included. For reference all sequences are included in the zip file with array data. References: Negre, V., T. Hotelier, et al. (2006). "SPODOBASE : an EST database for the lepidopteran crop pest Spodoptera." BMC Bioinformatics 7: 322.
Project description:The histone 3 lysine 9 acetylation (H3K9ac) is an epigenetic marker widely distributed in plant genome, which could eThe histone 3 lysine 9 acetylation (H3K9ac) is an epigenetic marker widely distributed in plant genome, which could enhance gene transcription involved in stress-responsive gene expression. The physiological and molecular mechanisms underlying plant responses to insects are being increasingly studied, while epigenetic modifications such as histone acetylation and their potential regulation at the genomic level of transcription of hidden genes in plants damaged by insects remain largely unknown. In current study, we provided the genome-wide profiles of H3K9ac in rice (Oryza sativa) infested by fall armyworm (Spodoptera frugiperda, FAW) using chromatin immunoprecipitation sequencing (ChIP-Seq) and RNA sequencing (RNA-seq). RNA-seq data revealed that 3269 and 4609 genes were up-regulated at 3 h and 12 h after infestation with FAW, respectively. ChIP-Seq analysis revealed 1617 and 2617 genes modified by H3K9ac in rice infested with FAW at 3 h and 12 h, respectively, and H3K9ac was mainly enriched in the transcription start sites of genes.
Project description:The aim of this experiment was to compare the transciptome of the fall armyworm (Spodoptera frugiperda) strain SUS (a laboratory insecticide-susceptible standard) with organophosphate (OP) and pyrethroid (PYR) resistant strains were collected in cornfields located in Minas Gerais and Mato Grosso States, Brazil, in 2008 and maintained in the laboratory under selection with chlorpyrifos (at increasing discriminating doses from 100 up to 400 M-BM-5g of insecticide/g of insect in a topical bioassay) or lambda-cyhalothrin (from 8.4 up to 27 M-BM-5g of insecticide/g of insect) respectively The custom microarray used in this study was designed using the Agilent eArray platform (Agilent Technologies). A SurePrint HD (8M-CM-^W15k) expression array was designed using the base composition and the best probe methodologies to design sense orientation 60-mer probes with a 3M-bM-^@M-2 bias. The FAW EST database (SPODOBASE) was used as the reference transcriptome (Negre, Hotelier et al. 2006). These sequences are derived from 8 cDNA libraries as follows: Sf1F: Fat body, Sf1H: Hemocyte, Sf1M: Midgut, Sf1P: Pool of various tissues, Sf2H: Immune Challenged hemocytes, Sf2L: Sf21 Cell lines sequences, Sf2M: Xenobiotic Induced Midgut and Sf9L: Sf9 cell lines sequences. All assembled contigs and singlets were kindly sent by the website maintainers. The BLAST2GO software v.2.3.1 (http://www.blast2go.org) was used to annotate the EST database. 60-mer probes were designed for all 7,552 assembled contigs and 5,519 annotated singlets (BlastX), totaling 13,071 sequences. For contigs encoding detoxification enzymes (P450s, GSTs and CEs) three probes were designed. Additional probe groups for 15 control genes were also included. For reference all sequences are included in the zip file with array data. References: Negre, V., T. Hotelier, et al. (2006). "SPODOBASE : an EST database for the lepidopteran crop pest Spodoptera." BMC Bioinformatics 7: 322. Two-condition experiment. Slide 1: SUS vs. OP S. fugiperda strains. Slide 2: SUS vs. PYR S. fugiperda strains. Biological replicates: 4 pools of RNA extracted from four pools of 5 second instar larvae. Technical Replicates: None, the biological replicates incorporated a dye swap. Total replication: four replicates for each strain.
Project description:The fall armyworm (FAW) Spodoptera frugiperda is one of the most severe economic pests of multiple crops globally. Control of this pest is often achieved using insecticides; however, over time, S. frugiperda has developed resistance to new mode of action compounds, including diamides. Previous studies have indicated diamide resistance is a complex developmental process involving multiple detoxification genes. Still, the mechanism underlying the possible involvement of microRNAs in post-transcriptional regulation of resistance has not yet been elucidated. In this study, a global screen of microRNAs (miRNAs) revealed 109 known and 63 novel miRNAs. Nine miRNAs (four known and five novel) were differentially expressed between insecticide-resistant and -susceptible strains. Gene Ontology analysis predicted putative target transcripts of the differentially expressed miRNAs encoding significant genes belonging to detoxification pathways. Additionally, miRNAs are involved in response to diamide exposure, indicating they are probably associated with the detoxification pathway. Thus, this study provides comprehensive evidence for the link between repressed miRNA expression and induced target transcripts that possibly mediate diamide resistance through post-transcriptional regulation. These findings highlight important clues for further research to unravel the roles and mechanisms of miRNAs in conferring diamide resistance.
Project description:Accurate chromosome segregation requires assembly of the multiprotein kinetochore complex at centromeres. In most eukaryotes, kinetochore assembly is primed by the histone H3 variant CenH3, which physically interacts with components of the inner kinetochore constitutive-centromere-associated-network (CCAN). Unexpected to its critical function, previous work identified that select eukaryotic lineages, including several insects, have lost CenH3, while having retained homologs of the CCAN. These findings imply alternative CCAN assembly pathways in these organisms that function in CenH3-independent manners. Here, we study the composition and assembly of CenH3-independent kinetochores of Lepidoptera. We show that lepidopteran kinetochores consist of previously identified CCAN homologs as well as additional components including a divergent CENP-T homolog, which are required for accurate mitotic progression. Our study focuses on CENP-T that we find both necessary and sufficient to recruit the Mis12 outer kinetochore complex. In addition, CRISPR-mediated gene editing in Bombyx mori establishes an essential function of CENP-T in vivo. Finally, the retention of CENP-T homologs in other independently-derived CenH3-deficient insects indicates a conserved mechanism of kinetochore assembly between these lineages. Our study provides the first functional insights into CCAN-based kinetochore assembly pathways that function independently of CenH3, thus contributing to the emerging picture of an unexpected plasticity to build a kinetochore.