Project description:Electro-addressable in vitro transcription system for random access and rewriting in dynamic DNA storage
| PRJNA1291395 | ENA
Project description:Magnetic DNA random access memory with exponentially scalable repeated file accessing, efficient encoding, and nanopore sequence reading
Project description:Replicates of strains used in comparison of microarray to RAPD analysis for the publication. Findings from use of an open-reading frame-specific Campylobacter jejuni DNA microarray to investigate genetic diversity among clinical isolates associated with 5 independent clusters of infection were compared with data from random amplified polymeric DNA (RAPD) and Penner serotyping analyses. The DNA microarray provides a highly specific epidemiological typing tool for analysis of C. jejuni isolates and reveals both divergent and highly conserved gene classes among isolates Set of arrays that are part of repeated experiments Keywords: Biological Replicate
Project description:Systemic inflammatory reactions mediated by chronic infections activate microglia in the central nervous system (CNS) and have been postulated to exacerbate neurodegenerative diseases. We now demonstrate in vivo that repeated systemic challenge of mice with bacterial lipopolysaccharides (LPS) maintains an elevated microglial inflammatory response and triggers neurodegeneration. Repeated chronic intraperitoneal application of LPS over four consecutive days induced loss of dopaminergic neurons in the substantia nigra, a process that was accompanied by decreased levels of dopamine in the striatum. In contrast, total cumulative LPS dose given intraperitoneally within a single acute application did not induce a decrease in dopamine levels nor neurodegeneration. Mice that received repeated systemic LPS application showed increased microglial activation, elevated production of proinflammatory cytokines and activation of the classical complement and its associated phagosome pathway in the brain. Loss of dopaminergic neurons induced by repeated systemic LPS application was rescued in complement C3 deficient mice, confirming an involvement of the complement system in neurodegeneration. Thus, our data demonstrate that repeated systemic exposure to bacterial LPS induces a microglial phagosomal inflammatory response, leading to complement-dependent damage of dopaminergic neurons.
Project description:High throughput sequencing is frequently used to discover the location of regulatory interactions on chromatin. However, techniques that enrich DNA where regulatory activity takes place, such as chromatin immunoprecipitation (ChIP), often yield less DNA than optimal for sequencing library preparation. Existing protocols for picogram-scale libraries require concomitant fragmentation of DNA, pre-amplification, or long overnight steps. We report a simple and fast library construction method that produces libraries from sub-nanogram quantities of DNA. This protocol yields conventional libraries with barcodes suitable for multiplexed sample analysis on the Illumina platform. We demonstrate the utility of this method by constructing a ChIP-seq library from 100 pg of ChIP DNA that demonstrates equivalent genomic coverage of target regions to a library produced from a larger scale experiment. Application of this method allows whole genome studies from samples where material or yields are limiting. Comparison of ChIP-seq libraries constructed from 100 pg DNA (this study) and nanograms of DNA (modENCODE). ChIP antibody: H3K27me3, Active Motif 31955.
Project description:Reporter genes integrated into the genome are a powerful tool to reveal effects of regulatory elements and local chromatin context on gene expression. However, so far such reporter assays have been of low throughput. Here we describe a multiplexing approach for the parallel monitoring of transcriptional activity of thousands of randomly integrated reporters. More than 27,000 distinct reporter integrations in mouse embryonic stem cells, obtained with two different promoters, show ~1,000-fold variation in expression levels. Data analysis indicates that lamina-associated domains act as attenuators of transcription, likely by reducing access of transcription factors to binding sites. Furthermore, chromatin compaction is predictive of reporter activity. We also found evidence for cross-talk between neighboring genes, and estimate that enhancers can influence gene expression on average over ~20 kb. The multiplexed reporter assay is highly flexible in design and can be modified to query a wide range of aspects of gene regulation. mRNA profiles of 11 mouse embryonic cell lines each harboring multiple barcoded reporter constructs with mouse PGK promoter integrated at random positions in the genome, single replicate.
Project description:Abstract Background: Gene transfer by electroporation (electro gene transfer) to muscle results in high level long term transgenic expression, showing great promise for treatment of e.g. protein deficiency syndromes. However little is known about the effects of electro gene transfer on muscle fibres. We have therefore investigated transcriptional changes through gene expression profile analyses, as well as morphological changes evaluated by histological analysis. Electro gene transfer was obtained using a combination of a short high voltage pulse (HV, 1000 V/cm, 100 @s) followed by a long low voltage pulse (LV, 100 V/cm, 400 ms); a pulse combination optimised for efficient and safe gene transfer. Muscles were transfected with green fluorescent protein (GFP) and excised at 4 hours, 48 hours or 3 weeks after treatment. Results: Differentially expressed genes were investigated by microarray analysis, and descriptive statistics were performed to evaluate the effects of 1) electroporation, 2) DNA injection, and 3) time after treatment. The biological significance of the results was assessed by gene annotation and supervised cluster analysis. Generally, electroporation caused down-regulation of structural proteins e.g. sarcospan and catalytic en-zymes such as phosphoenolpuryvate carboxykinase. Injection of DNA induced down-regulation of intracellular transport proteins e.g. sentrin. The effects on muscle fibres were transient as the expression profiles 3 weeks after treatment were closely related with the control muscles. Most interestingly, no changes in the expression of proteins involved in inflammatory responses or muscle regeneration was detected, indicating limited muscle damage and regeneration. Histological analysis revealed structural changes with loss of cell integrity and striation pattern in some fibres after DNA+HV+LV treatment, while electroporation alone caused minor loss of striation pattern but preservation of cell integrity. Conclusion: The small and transient changes found in the gene expression profiles are of great importance, as this demonstrates that electro gene transfer is safe with minor effects on the muscle host cells. These findings are essential for introducing the electro gene transfer to muscle for clinical use. Indeed the HV+LV pulse combination used have been optimised to ensure highly efficient and safe electro gene transfer. Keywords: Electro gene transfer, microarray, affymetrix, gene therapy, skeletal muscle, mouse, time course
Project description:Abstract; Background: Gene transfer by electroporation (electro gene transfer) to muscle results in high level long term transgenic expression, showing great promise for treatment of e.g. protein deficiency syndromes. However little is known about the effects of electro gene transfer on muscle fibres. We have therefore investigated transcriptional changes through gene expression profile analyses, as well as morphological changes evaluated by histological analysis. Electro gene transfer was obtained using a combination of a short high voltage pulse (HV, 1000 V/cm, 100 @s) followed by a long low voltage pulse (LV, 100 V/cm, 400 ms); a pulse combination optimised for efficient and safe gene transfer. Muscles were transfected with green fluorescent protein (GFP) and excised at 4 hours, 48 hours or 3 weeks after treatment. Results: Differentially expressed genes were investigated by microarray analysis, and descriptive statistics were performed to evaluate the effects of 1) electroporation, 2) DNA injection, and 3) time after treatment. The biological significance of the results was assessed by gene annotation and supervised cluster analysis. Generally, electroporation caused down-regulation of structural proteins e.g. sarcospan and catalytic en-zymes such as phosphoenolpuryvate carboxykinase. Injection of DNA induced down-regulation of intracellular transport proteins e.g. sentrin. The effects on muscle fibres were transient as the expression profiles 3 weeks after treatment were closely related with the control muscles. Most interestingly, no changes in the expression of proteins involved in inflammatory responses or muscle regeneration was detected, indicating limited muscle damage and regeneration. Histological analysis revealed structural changes with loss of cell integrity and striation pattern in some fibres after DNA+HV+LV treatment, while electroporation alone caused minor loss of striation pattern but preservation of cell integrity. Conclusion: The small and transient changes found in the gene expression profiles are of great importance, as this demonstrates that electro gene transfer is safe with minor effects on the muscle host cells. These findings are essential for introducing the electro gene transfer to muscle for clinical use. Indeed the HV+LV pulse combination used have been optimised to ensure highly efficient and safe electro gene transfer. Experiment Overall Design: The mice did recieve to their tibialis cranialis muscle either No tretment/control (CTRL), Electroporation only (EP), Plasmid injection only (DNA) or Plasmid DNA and in vivo Electro gene transfer (EP+DNA). Experiment Overall Design: Four hrs, 48 hrs and 3 weeks after treatment the mice were euthanized and the expression profile of the treated muscles were analysed. Experiment Overall Design: The following number of mice were included: Experiment Overall Design: CTRL, 3 mice, Experiment Overall Design: EP at 4 hrs, 1 mouse, Experiment Overall Design: EP at 48 hrs, 1 mouse, Experiment Overall Design: EP at 3 weeks, 1 mouse, Experiment Overall Design: DNA at 4 hrs, 1 mouse, Experiment Overall Design: DNA at 48 hrs, 1 mouse, Experiment Overall Design: DNA at 3 weeks, 1 mouse, Experiment Overall Design: EP+DNA at 4 hrs, 2 mice, Experiment Overall Design: EP+DNA at 48 hrs, 1 mouse, Experiment Overall Design: EP+DNA at 3 weeks, 1 mouse. Experiment Overall Design: A total number of mice 13.
Project description:<p>Energy metabolism is highly interdependent with adaptive cell migration <em>in vivo</em>. Mechanical confinement is a critical physical cue that induces switchable migration modes of the mesenchymal-to-amoeboid transition (MAT). However, the energy states in distinct migration modes, especially amoeboid-like stable bleb (A2) movement, remain unclear. In this report, we developed multivalent DNA framework-based nanomachines to explore strategical mitochondrial trafficking and differential ATP levels during cell migration in mechanically heterogeneous microenvironments. Through single-particle tracking and metabolomic analysis, we revealed that fast A2-moving cells driven by biomimetic confinement recruited back-end positioning of mitochondria for powering highly polarized cytoskeletal networks, preferentially adopting an energy-saving mode compared with a mesenchymal mode of cell migration. We present a versatile DNA nanotool for cellular energy exploration and highlight that adaptive energy strategies coordinately support switchable migration modes for facilitating efficient metastatic escape, offering a new perspective for therapeutic interventions in cancer metastasis.</p>
Project description:Replicates of strains used in comparison of microarray to RAPD analysis for the publication. Findings from use of an open-reading frame-specific Campylobacter jejuni DNA microarray to investigate genetic diversity among clinical isolates associated with 5 independent clusters of infection were compared with data from random amplified polymeric DNA (RAPD) and Penner serotyping analyses. The DNA microarray provides a highly specific epidemiological typing tool for analysis of C. jejuni isolates and reveals both divergent and highly conserved gene classes among isolates Set of arrays that are part of repeated experiments Biological Replicate Computed