Project description:The Sc2.0 project is building a eukaryotic synthetic genome from scratch. A major milestone has been achieved with all individual Sc2.0 chromosomes assembled. Here, we describe consolidation of multiple synthetic chromosomes using advanced endoreduplication intercrossing with tRNA expression cassettes to generate a strain with 6.5 synthetic chromosomes. The 3D chromosome organization and transcript isoform profiles were evaluated using Hi-C and long-read direct RNA sequencing. We developed CRISPR Directed Biallelic URA3-assisted Genome Scan, or “CRISPR D-BUGS”, to map phenotypic variants caused by specific designer modifications, known as “bugs”. We first fine-mapped a bug in synthetic chromosome II (synII), and then discovered a combinatorial interaction associated with synIII and synX, revealing an unexpected genetic interaction that links transcriptional regulation, inositol metabolism and tRNASerCGA abundance. Finally, to expedite consolidation, we employed chromosome substitution to incorporate the largest chromosome (synIV), thereby consolidating >50% of the Sc2.0 genome in one strain.
Project description:The common bed bug, Cimex lectularius, is an urban pest of global health significance, severely affecting the physical and mental health of humans. In contrast to most other blood-feeding arthropods, bed bugs are not major vectors of pathogens, but the underlying mechanisms for this phenomenon are largely unexplored. Here, we present the first transcriptomics study of bed bugs in response to immune challenges. To study transcriptional variations in bed begs following ingestion of bacteria, we extracted and processed mRNA from immune-related tissues of adult male bed bugs after ingestion of sterile blood or blood laced with the Gram-positive (Gr+) bacterium Bacillus subtilis or the Gram-negative (Gr–) bacterium Escherichia coli. We analyzed mRNA from the bed bugs’ midgut (the primary tissue involved in blood ingestion) and from the rest of their bodies (RoB; body minus head and midgut tissues).
Project description:A frightening resurgence of bed bug infestations has occurred over the last 10 years in the US. Current chemical methods have been inadequate for controlling bed bugs due to widespread insecticide resistance. Little is known about the mechanisms of resistance present in US bed bug populations, making it extremely difficult to develop intelligent strategies to control this pest. We have identified bed bugs collected in Richmond, VA which exhibit both kdr-type (L925I) and metabolic resistance to pyrethroid insecticides. LD50 bioassays determined resistance ratios of ~6000-fold to the insecticide deltamethrin, with contact bioassays confirming cross-resistance to several other labeled formulations. To identify metabolic genes potentially involved in the detoxification of pyrethroids, we performed deep-sequencing of the adult bed bug transcriptome, obtaining more than 2.5 million reads on the 454 titanium platform. Following assembly, analysis of newly identified gene transcripts in both Harlan (susceptible) and Richmond (resistant) bed bugs revealed several candidate cytochrome P450 and carboxyesterase genes which were significantly over-expressed in the resistant strain, consistent with the idea of increased metabolic resistance. These data will accelerate efforts to understand the biochemical basis for insecticide resistance in bed bugs, and provide molecular markers to assist in the surveillance of metabolic resistance.
2011-10-19 | GSE31025 | GEO
Project description:Microbes in the gut of triatomine bugs can negatively affect the growth of Trypanosoma cruzi.
Project description:A frightening resurgence of bed bug infestations has occurred over the last 10 years in the US. Current chemical methods have been inadequate for controlling bed bugs due to widespread insecticide resistance. Little is known about the mechanisms of resistance present in US bed bug populations, making it extremely difficult to develop intelligent strategies to control this pest. We have identified bed bugs collected in Richmond, VA which exhibit both kdr-type (L925I) and metabolic resistance to pyrethroid insecticides. LD50 bioassays determined resistance ratios of ~6000-fold to the insecticide deltamethrin, with contact bioassays confirming cross-resistance to several other labeled formulations. To identify metabolic genes potentially involved in the detoxification of pyrethroids, we performed deep-sequencing of the adult bed bug transcriptome, obtaining more than 2.5 million reads on the 454 titanium platform. Following assembly, analysis of newly identified gene transcripts in both Harlan (susceptible) and Richmond (resistant) bed bugs revealed several candidate cytochrome P450 and carboxyesterase genes which were significantly over-expressed in the resistant strain, consistent with the idea of increased metabolic resistance. These data will accelerate efforts to understand the biochemical basis for insecticide resistance in bed bugs, and provide molecular markers to assist in the surveillance of metabolic resistance. Deep sequencing was performed from total RNA isolated from adult male bed bugs using the Titanium 454 platform
Project description:The goal of this study was to use heterologous microarray hybridization to determine genomic content shared among different vesicomyid symbionts. These symbionts are closely related and can be thought of as different strains of bacteria, facilitating the use of heterologous microarray hybridization to determine genomic content. Keywords: comparative genomic hybridization
Project description:The goal of this study was to use heterologous microarray hybridization to determine genomic content shared among different vesicomyid symbionts. These symbionts are closely related and can be thought of as different strains of bacteria, facilitating the use of heterologous microarray hybridization to determine genomic content. Keywords: comparative genomic hybridization Microarrays were built off the Ruthia magnifica genome and two replicate hybridizations to this organism were used as a baseline for comparisons. Genomic DNA from two other vesicomyid symbionts (Calyptogena kilmeri and C. pacifica symbionts) was also hybridized to the array with three biological replicates for each sample.