Project description:During the over 300 million years of co-evolution between herbivorous insects and their host plants, a dynamic equilibrium of evolutionary arms race has been established. However, the co-adaptation between insects and their host plants is a complex process, often driven by multiple evolutionary mechanisms. We found that various lepidopteran pests that use maize as a host exhibit differential adaptation to the plant secondary metabolites, benzoxazinoids (BXs). Notably, the Spodoptera genus, including Spodoptera frugiperda (fall armyworm) and Spodoptera litura (cotton leafworm), demonstrate greater tolerance to BXs compared to other insects. Through comparative transcriptomic analysis of the midgut, we identified four candidate genes potentially involved in BXs detoxification in S. frugiperda. Subsequently, we confirmed two UGT genes, Sfru33T10 and Sfru33F32, as key players in BXs detoxification using CRISPR/Cas9 gene-editing technology. Phylogenetic analysis revealed that Sfru33T10 evolved independently within the Noctuidae family and is involved in the glycosylation of HDMBOA, while Sfru33F32 evolved independently within the Spodoptera genus and functions as a key detoxification enzyme responsible for the glycosylation of both DIMBOA and HMBOA. Our study demonstrates that the UGT gene family plays a crucial role in the adaptation of noctuid insects to maize, with multiple independent evolutionary events within the Noctuidae family and the Spodoptera genus contributing significantly to host adaptation.
2024-09-18 | GSE276946 | GEO
Project description:Genome Sequencing of the Malaysian Fall Armyworm (Spodoptera frugiperda)
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.
2023-09-01 | GSE233976 | GEO
Project description:Genome sequencing of Spodoptera frugiperda Benzon susceptible (fall armyworm) larval principal pseudohaplotype
| PRJNA867421 | ENA
Project description:Identification and characterization of highly active promoters from the fall armyworm, Spodoptera frugiperda
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:Although most known mycoviruses are asymptomatic or reduce the virulence of their host fungi, those that confer hypervirulence to entomopathogenic fungus still need to be explored. Here, we discovered and studied a novel mycovirus in Metarhizium flavoviride, isolated from Laodelphax striatellus. Based on molecular analysis, we tentatively designated the mycovirus as Metarhizium flavoviride partitivirus 1 (MfPV1), a novel species in genus Gammapartitivirus, family Partitiviridae. MfPV1 has two double-stranded (ds) RNAs as its genome, 1,775 and 1,575 bp in size respectively, encapsidated in isometric particles. When we transfected commercial strains of M. anisopliae and M. pingshaense with MfPV1, conidiation was significantly enhanced (t-test; P-value < 0. 01), and the significantly higher mortality rates of the larvae of Plutella xylostella and Spodoptera frugiperda, two important lepidopteran pests were found in virus-transfected strains (ANOVA; P-value < 0.05). Transcriptomic analysis showed that transcript levels of pathogenesis-related genes in MfPV1-infected M. anisopliae were obviously altered, suggesting increased production of metarhizium adhesin-like protein, hydrolyzed protein and destruxin synthetase. Further studies are required to elucidate the mechanism whereby MfPV1 enhances the expression of pathogenesis-related genes and virulence of Metarhizium to lepidopteran pests. This study presents experimental evidence that the transfection of other entomopathogenic fungal species with a mycovirus can confer significant hypervirulence and provides a good example that mycoviruses could be used as synergistic agent to enhance the biocontrol activity of entomopathogenic fungi.