E-GEOD-59460
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ABSTRACT:
OTHER RELATED OMICS DATASETS IN: PRJNA255376PRJNA255427
PROVIDER: E-GEOD-59460 | ExpressionAtlas | 2015-01-28
REPOSITORIES: ExpressionAtlas
Similar Datasets
Project description:Mammalian transcriptomes display complex circadian rhythms with multiple phases of gene expression that cannot be accounted for by current models of the molecular clock. We have determined the underlying mechanisms by measuring nascent RNA transcription around the clock in mouse liver. Unbiased examination of eRNAs that cluster in specific circadian phases identified functional enhancers driven by distinct transcription factors (TFs). We further identify on a global scale the components of the TF cistromes that function to orchestrate circadian gene expression. Integrated genomic analyses also revealed novel mechanisms by which a single circadian factor controls opposing transcriptional phases. These findings shed new light on the diversity and specificity of TF function in the generation of multiple phases of circadian gene transcription in a mammalian organ. The goal of this experiment was to determine direct targets of Rev-erb{alpha} in mouse liver. All samples were collected at ZT10, when Rev-erb{alpha} protein levels and genomic binding are maximal. All mice were housed and harvested together (n=5 per genotype). All mice were male, 10-12 week old on C57Bl/6 background. RNA was extracted, processed, and hybridized from each mouse liver individually (each sample represents a single mouse).
2015-01-06 | E-GEOD-59460 | biostudies-arrayexpress
Project description:Mammalian transcriptomes display complex circadian rhythms with multiple phases of gene expression that cannot be accounted for by current models of the molecular clock. We have determined the underlying mechanisms by measuring nascent RNA transcription around the clock in mouse liver. Unbiased examination of eRNAs that cluster in specific circadian phases identified functional enhancers driven by distinct transcription factors (TFs). We further identify on a global scale the components of the TF cistromes that function to orchestrate circadian gene expression. Integrated genomic analyses also revealed novel mechanisms by which a single circadian factor controls opposing transcriptional phases. These findings shed new light on the diversity and specificity of TF function in the generation of multiple phases of circadian gene transcription in a mammalian organ. The goal of this experiment was to determine direct targets of Rev-erb{alpha} in mouse liver. All samples were collected at ZT10, when Rev-erb{alpha} protein levels and genomic binding are maximal.
2015-01-06 | GSE59460 | GEO
Project description:Using chromatin immuno-precipitation (ChIP) combined with deep sequencing (ChIP-seq) we obtained a time resolved and genome-wide map of BMAL1 binding in mouse liver, which allowed to identify over two thousand binding sites with peak binding narrowly centered around Zeitgeber time (ZT) 6. Annotation of BMAL1 targets confirms carbohydrate and lipid metabolism as the major output of the circadian clock in mouse liver. Moreover, transcription regulators are largely overrepresented, several of which also exhibit circadian activity. Genes of the core circadian oscillator stand out as strongly bound, often at promoter and distal sites. Genomic sequence analysis of the sites identified E- boxes and tandem E1-E2 consensus elements. Electromobility shift assays (EMSA) showed that E1-E2 sites are bound by a dimer of BMAL1/CLOCK heterodimers with a spacing-dependent cooperative interaction that was further validated in transactivation assays. BMAL1 target genes showed cyclic mRNA expression profiles with a phase distribution centered at ZT10. Importantly, sites with E1-E2 elements showed tighter phases both in binding and mRNA accumulation. Finally, comparing the temporal accumulation of precursor mRNA and mature mRNA helped distinguish direct BMAL1 targets from targets with more complex regulation, and showed how transcriptional and post-transcriptional regulation contribute differentially to circadian expression phase. Together, our analysis of a dynamic protein-DNA interactome uncovered how genes of the core circadian oscillator are wired together and drive phase-specific circadian output programs in a complex tissue. ChIP-Seq of BMAL1 in mouse liver during one circadian cycle at 4 hour time resolution presented in this Series (GSE26602). mRNA profiling data used in this study are already published (Kornmann et al, PLoS Biol 2007) and have been deposited on ArrayExpress repository (accession number: E-MEXP-842).
2011-02-23 | E-GEOD-26602 | biostudies-arrayexpress
Project description:Obesity and liver diseases are associated with the disruption of the circadian clock that orchestrates mammalian physiology to optimize nutrient metabolism and storage. We show here that the activity of the circadian clock regulator BMAL1 is perturbed during liver fibrosis in humans. To understand the impact of BMAL1 perturbation in obesity and liver diseases, we assessed the impact of a high fat diet or leptin deficiency on Bmal1 knockout mice. While Bmal1 knockout mice were prone to obesity, they were protected against insulin resistance, hepatic steatosis, inflammation, and fibrosis. In addition to direct transcriptional regulation of metabolic programs by BMAL1, we show that adaptation disruption of the growth hormone and sex hormone pathways plays a critical role in this protection. Similar endocrine perturbations correlate with the development of liver fibrosis in humans, but were absent in hepatocyte specific Bmal1 knockout mice. This suggestsing that systemic endocrine perturbation associated with circadian disruptionthe disruption of BMAL1 activity is critical for the pathogenesis of metabolic and liver diseases.
2022-01-26 | GSE150102 | GEO
Project description:Obesity and liver diseases are associated with the disruption of the circadian clock that orchestrates mammalian physiology to optimize nutrient metabolism and storage. We show here that the activity of the circadian clock regulator BMAL1 is perturbed during liver fibrosis in humans. To understand the impact of BMAL1 perturbation in obesity and liver diseases, we assessed the impact of a high fat diet or leptin deficiency on Bmal1 knockout mice. While Bmal1 knockout mice were prone to obesity, they were protected against insulin resistance, hepatic steatosis, inflammation, and fibrosis. In addition to direct transcriptional regulation of metabolic programs by BMAL1, we show that adaptation of the growth hormone and sex hormone pathways plays a critical role in this protection. Similar endocrine perturbations correlate with the development of liver fibrosis in humans, suggesting that endocrine perturbation associated with circadian disruption is critical for the pathogenesis of metabolic and liver diseases.
2022-01-26 | GSE190221 | GEO
Project description:Hepatic lipid metabolism is highly dynamic, and disruption of several circadian transcriptional regulators results in hepatic steatosis. This includes genetic disruption of the glucocorticoid receptor (GR) as the liver develops. To address the functional role of GR in the adult liver, we used an acute hepatocyte-specific GR knockout model (hepGRKO) to study temporal hepatic lipid metabolism governed by GR at several pre- and postprandial timepoints. Lipidomics analysis revealed significant temporal lipid metabolism, with GR disruption resulting in impaired regulation of specific triglycerides, non-esterified fatty acids, and sphingolipids. This correlated with increased number and size of lipid droplets and mildly reduced mitochondrial respiration, most noticeably in the postprandial phase. Proteomics and transcriptomics analyses suggest that dysregulated lipid metabolism originates from pronounced induced expression of enzymes involved in fatty acid synthesis, -oxidation, and sphingolipid metabolism. Integration of GR cistromic data suggests that induced genes are a result of regulatory actions secondary to direct GR effects on transcription.
2023-09-07 | PXD041168 | Pride
Project description:The PAR-domain basic leucine zipper (PAR bZip) transcription factors DBP, TEF, and HLF accumulate in a highly circadian manner in several peripheral tissues, including liver and kidney. Mice devoid of all three of these proteins are born at expected Mendelian ratios, but are epilepsy-prone, age at an accelerated rate and die prematurely. In the hope of identifying PAR bZip target genes whose altered expression might contribute to the high morbidity and mortality of PAR bZip triple knockout mice, we compared the liver and kidney transcriptomes of these animals to those of wild-type or heterozygous mutant mice. These experiments revealed that PAR bZip proteins control the expression of many enzymes and regulators involved in detoxification and drug metabolism, such as cytochrome P450 enzymes, carboxylesterases, and constitutive androstane receptor (CAR). Indeed, PAR bZip triple knockout mice are hypersensitive to xenobiotic compounds, and the deficiency in detoxification may contribute to their early ageing.
2006-12-20 | E-MEXP-565 | biostudies-arrayexpress
Project description:Over the past decade, genome-wide assays have underscored the broad sweep of circadian gene expression. A substantial fraction of the transcriptome undergoes oscillations in many organisms and tissues, which governs the many biochemical, physiological and behavioral functions under circadian control. Based predominantly on the transcription feedback loops important for core circadian timekeeping, it is commonly assumed that this widespread mRNA cycling reflects circadian transcriptional cycling. To address this issue, we directly measured dynamic changes in mouse liver transcription using Nascent-Seq. Many genes are rhythmically transcribed over the 24h day, which include precursors of several non-coding RNAs as well as the expected set of core clock genes. Surprisingly however, nascent RNA rhythms overlap poorly with mRNA abundance rhythms assayed by RNA-seq. This is because most mouse liver genes with rhythmic mRNA expression manifest poor transcriptional rhythms, indicating a prominent role of post-transcriptional regulation in setting mRNA cycling amplitude. To gain further insight into circadian transcriptional regulation, we also characterized the rhythmic transcription of liver genes targeted by the transcription factors CLOCK and BMAL1; they directly target other core clock genes and sit at the top of the molecular circadian clock hierarchy in mammals. CLK:BMAL1 rhythmically bind at the same discrete phase of the circadian cycle to all target genes, which not surprisingly have a much higher percentage of rhythmic transcription than the genome as a whole. However, there is a surprisingly heterogeneous set of cycling transcription phases of direct target genes, which even include core clock genes. This indicates a disconnect between rhythmic DNA binding and the peak of transcription, which is likely due to other transcription factors that collaborate with CLK:BMAL1. In summary, the application of Nascent-Seq to a mammalian tissue provides surprising insights into the rhythmic control of gene expression and should have broad applications beyond the analysis of circadian rhythms. CLK and BMAL1 DNA binding profile in the mouse liver at ZT8, sequenced along an Input sample using GAII (ChIP-Seq) Supplementary file ChIPSeq_Mouse_Liver_Processed_data_Table1.txt represents annotated CLK and BMAL1 peaks.
2012-11-10 | E-GEOD-36874 | biostudies-arrayexpress
Project description:Over the past decade, genome-wide assays have underscored the broad sweep of circadian gene expression. A substantial fraction of the transcriptome undergoes oscillations in many organisms and tissues, which governs the many biochemical, physiological and behavioral functions under circadian control. Based predominantly on the transcription feedback loops important for core circadian timekeeping, it is commonly assumed that this widespread mRNA cycling reflects circadian transcriptional cycling. To address this issue, we directly measured dynamic changes in mouse liver transcription using Nascent-Seq. Many genes are rhythmically transcribed over the 24h day, which include precursors of several non-coding RNAs as well as the expected set of core clock genes. Surprisingly however, nascent RNA rhythms overlap poorly with mRNA abundance rhythms assayed by RNA-seq. This is because most mouse liver genes with rhythmic mRNA expression manifest poor transcriptional rhythms, indicating a prominent role of post-transcriptional regulation in setting mRNA cycling amplitude. To gain further insight into circadian transcriptional regulation, we also characterized the rhythmic transcription of liver genes targeted by the transcription factors CLOCK and BMAL1; they directly target other core clock genes and sit at the top of the molecular circadian clock hierarchy in mammals. CLK:BMAL1 rhythmically bind at the same discrete phase of the circadian cycle to all target genes, which not surprisingly have a much higher percentage of rhythmic transcription than the genome as a whole. However, there is a surprisingly heterogeneous set of cycling transcription phases of direct target genes, which even include core clock genes. This indicates a disconnect between rhythmic DNA binding and the peak of transcription, which is likely due to other transcription factors that collaborate with CLK:BMAL1. In summary, the application of Nascent-Seq to a mammalian tissue provides surprising insights into the rhythmic control of gene expression and should have broad applications beyond the analysis of circadian rhythms. Mouse liver nascent RNA profile over 6 time points of the 24h light:dark cycle, in duplicate, sequenced using Ilumina GAII (Nascent-Seq); Mouse liver mRNA profile over 6 time points of the 24h light:dark cycle, in duplicate, sequenced using Ilumina HiSeq2000 (RNA-Seq); CLK and BMAL1 DNA binding profile in the mouse liver at ZT8, sequenced along an Input sample using GAII (ChIP-Seq); Mouse liver strand-specific nascent RNA profile over 6 time points of the 24h light:dark cycle, in duplicate, sequenced using Ilumina HiSeq2000 (Strand-specific Nascent-Seq);
2012-11-10 | E-GEOD-36873 | biostudies-arrayexpress
Project description:The circadian clock acts at the genomic level to coordinate internal behavioral and physiologic rhythms via the CLOCK-BMAL transcriptional heterodimer. Although the nuclear receptors REV-ERB? and ? have been proposed to contribute to clock function, their precise roles and importance remain unresolved. To establish their regulatory potential we generated comparative cistromes of both Rev-erb isoforms, which revealed shared recognition at over ~50% of their total sites and extensive overlap with the master clock regulator Bmal. While Rev-erb? has been shown to directly regulate Bmal expression, the cistromic analysis reveals a more profound connection between Bmal and Rev-erb? and ? regulatory circuits than previously suspected. Genes within the intersection of the Bmal and Rev-erb cistromes are highly enriched for both clock and metabolic functions. As predicted by the cistromic analysis, dual depletion of Rev-erb?/? function by creating double-knockout mice (DKOs) profoundly disrupted circadian expression of core clock and lipid homeostatic genes. As a result, DKOs show strikingly altered circadian wheel-running behavior and deregulated lipid metabolism. These data reveal an integral role of Rev-erb?/? in clock function as well as provide a cistromic basis for the integration of circadian rhythm and metabolism. Total RNA was obtained from livers of wild-type and Liver-specific Reverb alpha/beta double knockout mice at ZT 0, 4, 8, 12, 16, and 20.
2012-03-28 | E-GEOD-34018 | biostudies-arrayexpress