Project description:Bacillus thuringiensis israelensis (Bti) toxins are increasingly used for mosquito control, but little is known about the precise mode of action of each of these toxins, and how they interact to kill mosquito larvae. By using RNA sequencing, we investigated change in gene transcription level and polymorphismvariations associatedwith resistance to each Bti Cry toxin and to the full Bti toxin mixture in the dengue vector Aedes aegypti. The upregulation of genes related to chitin metabolismin all selected strain suggests a generalist, non-toxin-specific response to Bti selection in Aedes aegypti. Changes in the transcription level and/or protein sequences of several putative Cry toxin receptors (APNs, ALPs, α-amylases, glucoside hydrolases, ABC transporters) were specific to each Cry toxin. Selective sweeps associated with Cry4Aa resistancewere detected in 2 ALP and 1 APNgenes. The lack of selection of toxin-specific receptors in the Bti-selected strain supports the hypothesis that Cyt toxin acts as a receptor for Cry toxins in mosquitoes.
Project description:To determine Sigma 54 (SigL) reglons in Bacillus thuringiensis HD73 strain, A sigLmutant, HD(ΔsigL::kan), was constructed with insertion of kanamycin resistance gene cassete. We have employed whole genome microarray expression profiling as a discovery platform to identify the difference of gene expression between mutant and wild-type strains.
Project description:We investigated the gene expression and metabolic regulatory mechanisms associated with the high-level accumulation of ICPs by performing the transcriptomics analysis of B. thuringiensis strain CT-43, using Illumina high throughout sequencing (RNA-seq) technique.
Project description:To determine Sigma 54 (SigL) reglons in Bacillus thuringiensis HD73 strain, A sigLmutant, HD(M-NM-^TsigL::kan), was constructed with insertion of kanamycin resistance gene cassete. We have employed whole genome microarray expression profiling as a discovery platform to identify the difference of gene expression between mutant and wild-type strains. 2 ml samples were separately harvested from B. thuringiensis HD73 and HD(M-NM-^TsigL::kan) strains grown in SchaefferM-bM-^@M-^Ys sporulation medium (SSM) at stages T7 of stationary phase (7 hours after the end of the exponential phase). Three independent repeats were performed for each stain.
Project description:This study aimed at comparing gene transcription using microarrays and protein expression using 2D-DIGE between an Aedes aegypti insecticide-resistant strain (LiTOX) selected for 28 generations at the larval stage with field-collected leaf litter containing persistent Bacillus thuringiensis var. israelensis (Bti) toxins and the parental strain (Bora-Bora) susceptible to all insecticides. We focused on the tissue where the mode of action of the insecticide takes place: the midgut of the larvae.
Project description:We investigated the gene expression and metabolic regulatory mechanisms associated with the high-level accumulation of ICPs by performing the transcriptomics analysis of B. thuringiensis strain CT-43, using Illumina high throughout sequencing (RNA-seq) technique. The bacterial cells were collected at the time points of 7 h, 9 h, 13 h and 22 h for the whole-genome transcriptomics, respectively.
Project description:Transcriptional profiling of C. elegans nasp-1 / btr-1 mutant worms versus wild type N2 strain, both exposed to the bacterial pathogen Bacillus thuringiensis DB27.
Project description:Transcriptional profiling of C. elegans nasp-1 / btr-1 mutant worms versus wild type N2 strain, both exposed to the bacterial pathogen Bacillus thuringiensis DB27. One-condition experiment. C. elegans nasp-1 / btr-1 mutant versus N2, exposed to Bacillus thuringiensis DB27. 3 biological replicates, including 1 dye-swaps.
