Escherichia coli str. K-12 substr. MG1655
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ABSTRACT:
PROVIDER: PRJNA224578 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Despite the prevalence of antisense transcripts in bacterial transcriptomes, little is known about how their synthesis is controlled. We report that a major function of the Escherichia coli termination factor Rho and its co-factor NusG is suppression of ubiquitous antisense transcription genome-wide. Rho binds C-rich unstructured nascent RNA (high C/G ratio) prior to its ATP-dependent dissociation of transcription complexes. NusG is required for efficient termination at minority subsets (~20%) of both antisense and sense Rho-dependent terminators with lower C/G ratio sequences. In contrast, a widely studied nusA deletion proposed to compromise Rho-dependent termination had no effect on antisense or sense Rho-dependent terminators in vivo. Global co-localization of the nucleoid-associated protein H-NS with Rho-dependent terminators and genetic interactions between hns and rho suggest that H-NS aids Rho in suppression of antisense transcription. The combined actions of Rho, NusG, and H-NS appear to be analogous to the Sen1-Nrd1-Nab3 and nucleosome systems that suppress antisense transcription in eukaryotes. RNA-seq experiments were performed on ribosome-depleted RNA from cells treated with 20 ug/ml bicyclomycin or untreated cells. The series contains 4 datasets.
2012-11-01 | E-GEOD-41939 | biostudies-arrayexpress
Project description:We report that inhibition of rho by treatment with bicyclomycin, a potential inhibitor of rho affects H-NS binding to chromosome across most of the binding sites. For the current study, we have flag tagged H-NS by homologous recomination method. Cells were grown in the presence and absence of antibiotic bicylomyin. Chromatin immunoprecipitation was performed and anti flag antibody was used for immunoprecipitation. Immunoprecipitated samples both from BCM- and BCM + conditions were sequenced using HiSeq 1000 model. Input DNA was used as control for this experiment which was also sequenced. The 50-mer reads obtained were then mapped to Escherichia coli Mg1655 K-12 genome. Further analysis was carried out to calculate the ChIP signal score. We observed a drop in ChIP signal for bcm+ condition as compared to bcm-.
2014-01-01 | GSE51582 | GEO
Project description:Despite the prevalence of antisense transcripts in bacterial transcriptomes, little is known about how their synthesis is controlled. We report that a major function of the Escherichia coli termination factor Rho and its co-factor NusG is suppression of ubiquitous antisense transcription genome-wide. Rho binds C-rich unstructured nascent RNA (high C/G ratio) prior to its ATP-dependent dissociation of transcription complexes. NusG is required for efficient termination at minority subsets (~20%) of both antisense and sense Rho-dependent terminators with lower C/G ratio sequences. In contrast, a widely studied nusA deletion proposed to compromise Rho-dependent termination had no effect on antisense or sense Rho-dependent terminators in vivo. Global co-localization of the nucleoid-associated protein H-NS with Rho-dependent terminators and genetic interactions between hns and rho suggest that H-NS aids Rho in suppression of antisense transcription. The combined actions of Rho, NusG, and H-NS appear to be analogous to the Sen1-Nrd1-Nab3 and nucleosome systems that suppress antisense transcription in eukaryotes. Tiling expression microarray experiments were performed in cells treated with 20 ug/ml bicyclomycin or cells deleted for nusG, or a partial deletion of nusA. Labeled cDNAs were hybridized to an E. coli K-12 MG1655 tiling array with overlapping probes at ~12bp spacing across the entire genome. The series contains 14 datasets.
2012-11-01 | E-GEOD-41938 | biostudies-arrayexpress
Project description:Transcription termination factor Rho is essential in enterobacteria. We inhibited Rho activity with bicyclomycin and used microarray experiments to assess Rho function on a genome-wide scale. Rho is a global regulator of gene expression that matches E. coli transcription to translational needs. Remarkably, genes that are most repressed by Rho are prophages and other horizontally-acquired portions of the genome. Elimination of these foreign DNA elements increases resistance to bicyclomycin. Although rho remains essential, such reduced-genome bacteria no longer require Rho cofactors NusA and NusG. Thus, Rho termination, supported by NusA and NusG, is required to suppress the toxic activity of foreign DNA. Global regulation of transcription termination by Rho, NusA, and NusG. Experiment Overall Design: Two sets of experiments are presented. First, treatment of E. coli with Rho inhibitor bicyclomycin was performed in strains MG1655 and O157:H7 EDL933 for twenty minutes at concentrations of 10, 25, or 100 micrograms/milliliter. In the second set of experiments the reduced-genome strain MDS42 was treated with bicyclomycin as well as having deletions of the genes nusA and nusG. Total RNA was extracted and hybridized to the Affymetrix E. coli Genome 2.0 array, which contains complete genome coverage of four strains of E. coli.
2008-06-20 | E-GEOD-10345 | biostudies-arrayexpress
Project description:Transcription termination factor Rho is essential in enterobacteria. We inhibited Rho activity with bicyclomycin and used microarray experiments to assess Rho function on a genome-wide scale. Rho is a global regulator of gene expression that matches E. coli transcription to translational needs. Remarkably, genes that are most repressed by Rho are prophages and other horizontally-acquired portions of the genome. Elimination of these foreign DNA elements increases resistance to bicyclomycin. Although rho remains essential, such reduced-genome bacteria no longer require Rho cofactors NusA and NusG. Thus, Rho termination, supported by NusA and NusG, is required to suppress the toxic activity of foreign DNA. Global regulation of transcription termination by Rho, NusA, and NusG. Keywords: Antibiotic treatment
2008-05-16 | GSE10345 | GEO
Project description:We report that inhibition of rho by treatment with bicyclomycin, a potential inhibitor of rho affects H-NS binding to chromosome across most of the binding sites. For the current study, we have flag tagged H-NS by homologous recomination method. Cells were grown in the presence and absence of antibiotic bicylomyin. Chromatin immunoprecipitation was performed and anti flag antibody was used for immunoprecipitation. Immunoprecipitated samples both from BCM- and BCM + conditions were sequenced using HiSeq 1000 model. Input DNA was used as control for this experiment which was also sequenced. The 50-mer reads obtained were then mapped to Escherichia coli Mg1655 K-12 genome. Further analysis was carried out to calculate the ChIP signal score. We observed a drop in ChIP signal for bcm+ condition as compared to bcm-. ChIP-seq data generated by Hiseq 1000 model of samples with bcm+ and bcm- in biological duplicates along with Input DNA as control
2014-01-01 | E-GEOD-51582 | biostudies-arrayexpress
Project description:Despite the prevalence of antisense transcripts in bacterial transcriptomes, little is known about how their synthesis is controlled. We report that a major function of the Escherichia coli termination factor Rho and its co-factor NusG is suppression of ubiquitous antisense transcription genome-wide. Rho binds C-rich unstructured nascent RNA (high C/G ratio) prior to its ATP-dependent dissociation of transcription complexes. NusG is required for efficient termination at minority subsets (~20%) of both antisense and sense Rho-dependent terminators with lower C/G ratio sequences. In contrast, a widely studied nusA deletion proposed to compromise Rho-dependent termination had no effect on antisense or sense Rho-dependent terminators in vivo. Global co-localization of the nucleoid-associated protein H-NS with Rho-dependent terminators and genetic interactions between hns and rho suggest that H-NS aids Rho in suppression of antisense transcription. The combined actions of Rho, NusG, and H-NS appear to be analogous to the Sen1-Nrd1-Nab3 and nucleosome systems that suppress antisense transcription in eukaryotes.
2012-11-01 | GSE41939 | GEO
Project description:Despite the prevalence of antisense transcripts in bacterial transcriptomes, little is known about how their synthesis is controlled. We report that a major function of the Escherichia coli termination factor Rho and its co-factor NusG is suppression of ubiquitous antisense transcription genome-wide. Rho binds C-rich unstructured nascent RNA (high C/G ratio) prior to its ATP-dependent dissociation of transcription complexes. NusG is required for efficient termination at minority subsets (~20%) of both antisense and sense Rho-dependent terminators with lower C/G ratio sequences. In contrast, a widely studied nusA deletion proposed to compromise Rho-dependent termination had no effect on antisense or sense Rho-dependent terminators in vivo. Global co-localization of the nucleoid-associated protein H-NS with Rho-dependent terminators and genetic interactions between hns and rho suggest that H-NS aids Rho in suppression of antisense transcription. The combined actions of Rho, NusG, and H-NS appear to be analogous to the Sen1-Nrd1-Nab3 and nucleosome systems that suppress antisense transcription in eukaryotes.
2012-11-01 | GSE41938 | GEO
Project description:Despite the prevalence of antisense transcripts in bacterial transcriptomes, little is known about how their synthesis is controlled. We report that a major function of the Escherichia coli termination factor Rho and its co-factor NusG is suppression of ubiquitous antisense transcription genome-wide. Rho binds C-rich unstructured nascent RNA (high C/G ratio) prior to its ATP-dependent dissociation of transcription complexes. NusG is required for efficient termination at minority subsets (~20%) of both antisense and sense Rho-dependent terminators with lower C/G ratio sequences. In contrast, a widely studied nusA deletion proposed to compromise Rho-dependent termination had no effect on antisense or sense Rho-dependent terminators in vivo. Global co-localization of the nucleoid-associated protein H-NS with Rho-dependent terminators and genetic interactions between hns and rho suggest that H-NS aids Rho in suppression of antisense transcription. The combined actions of Rho, NusG, and H-NS appear to be analogous to the Sen1-Nrd1-Nab3 and nucleosome systems that suppress antisense transcription in eukaryotes.
2012-11-01 | GSE41936 | GEO
Project description:The transcription termination factor Rho is a global regulator of RNA polymerase (RNAP). Although individual Rho-dependent terminators have been studied extensively, less is known about the sites of RNAP regulation by Rho on a genome-wide scale. Using chromatin immunoprecipitation and microarrays (ChIP-chip), we examined changes in the distribution of Escherichia coli RNAP in response to the Rho-specific inhibitor bicyclomycin (BCM). We found ~200 Rho-terminated loci that were divided evenly into two classes: intergenic (at the ends of genes) and intragenic (within genes). The intergenic class contained noncoding RNAs such as small RNAs (sRNAs) and transfer RNAs (tRNAs), establishing a previously unappreciated role of Rho in termination of stable RNA synthesis. The intragenic class of terminators included a novel set of short antisense transcripts, as judged by a shift in the distribution of RNAP in BCM-treated cells that was opposite to the direction of the corresponding gene. These Rho-terminated antisense transcripts point to a novel role of noncoding transcription in E. coli gene regulation that may resemble the ubiquitous noncoding transcription recently found to play myriad roles in eukaryotic gene regulation. Chromatin immunoprecipitation (ChIP) experiments were performed using antibodies against RNA polymerase (Beta or Beta' subunit) in cells treated with 20ug/ml bicyclomycin or untreated cells. Differentially labeled ChIP DNA and genomic DNA were competitively hybridized to an E. coli K-12 MG1655 tiling array with overlapping probes at ~12bp spacing across the entire genome. The series contains 4 datasets.
2010-05-18 | E-GEOD-16562 | biostudies-arrayexpress