Transcriptional Architecture and Chromatin Landscape of the Core Circadian Clock in Mammals
Ontology highlight
ABSTRACT:
ORGANISM(S): Mus musculus
SUBMITTER: Joseph Takahashi
PROVIDER: E-GEOD-39860 | biostudies-arrayexpress |
REPOSITORIES: biostudies-arrayexpress
Publications
Transcriptional architecture and chromatin landscape of the core circadian clock in mammals.
Koike Nobuya N Yoo Seung-Hee SH Huang Hung-Chung HC Kumar Vivek V Lee Choogon C Kim Tae-Kyung TK Takahashi Joseph S JS
Science (New York, N.Y.) 20120830 6105
The mammalian circadian clock involves a transcriptional feed back loop in which CLOCK and BMAL1 activate the Period and Cryptochrome genes, which then feedback and repress their own transcription. We have interrogated the transcriptional architecture of the circadian transcriptional regulatory loop on a genome scale in mouse liver and find a stereotyped, time-dependent pattern of transcription factor binding, RNA polymerase II (RNAPII) recruitment, RNA expression, and chromatin states. We find ...[more]
Similar Datasets
Project description:The mammalian circadian clock involves a transcriptional feedback loop in which CLOCK and BMAL1 activate the Period and Cryptochrome genes, which then feedback and repress their own transcription. We have interrogated the transcriptional architecture of the circadian transcriptional regulatory loop on a genome scale in mouse liver and find a stereotyped, time-dependent pattern of transcription factor binding, RNA polymerase II (RNAPII) recruitment, RNA expression and chromatin states. We find that the circadian transcriptional cycle of the clock consists of three distinct phases - a poised state, a coordinated de novo transcriptional activation state, and a repressed state. Interestingly only 22% of mRNA cycling genes are driven by de novo transcription, suggesting that both transcriptional and post-transcriptional mechanisms underlie the mammalian circadian clock. We also find that circadian modulation of RNAPII recruitment and chromatin remodeling occurs on a genome-wide scale far greater than that seen previously by gene expression profiling. Examination of 9 transcriptional regulators, 2 RNAPII and 6 histone modifications every 4hr during the circadian cycle in mouse liver
2012-08-31 | E-GEOD-39977 | biostudies-arrayexpress
Project description:Genetic and molecular approaches have been critical for elucidating the mechanism of the mammalian circadian clock. Here, we demonstrate that the ClockM-NM-^T19 mutant behavioral phenotype is significantly modified by mouse strain genetic background. We map a suppressor of the ClockM-NM-^T19 mutation to a M-bM-^HM-<900 kb interval on mouse chromosome 1 and identify the transcription factor, Usf1, as the responsible gene. A SNP in the promoter of Usf1 causes elevation of its transcript and protein in strains that suppress the Clock mutant phenotype. USF1 competes with the CLOCK:BMAL1 complex for binding to E-box sites in target genes. Saturation binding experiments demonstrate reduced affinity of the CLOCKM-NM-^T19:BMAL1 complex for E-box sites, thereby permitting increased USF1 occupancy on a genome-wide basis. We propose that USF1 is an important modulator of molecular and behavioral circadian rhythms in mammals. DOI:http://dx.doi.org/10.7554/eLife.00426.001. Examination of 3 transcriptional regulators in mouse liver at ZT8
2013-04-21 | E-GEOD-44609 | biostudies-arrayexpress
Project description:We used genome-wide sequencing methods to study stimulus-dependent enhancer function in neurons. We identified ~12,000 neuronal activity-regulated enhancers that are bound by the general transcriptional co-activator CBP in an activity-dependent manner. A function of CBP at enhancers may be to recruit RNA polymerase II (RNAPII), as we also observed activity-regulated RNAPII binding to thousands of enhancers. Remarkably, RNAPII at enhancers transcribes bi-directionally a novel class of enhancer RNAs (eRNAs) within enhancer domains defined by the presence of histone H3 that is mono-methylated at lysine 4 (H3K4me1). The level of eRNA expression at neuronal enhancers positively correlates with the level of mRNA synthesis at nearby genes, suggesting that eRNA synthesis occurs specifically at enhancers that are actively engaged in promoting mRNA synthesis. These findings reveal that a widespread mechanism of enhancer activation involves RNAPII binding and eRNA synthesis. Examination of genome-wide binding of three types of modified histones, four transcription factors, and RNA polymerase II (ChIP-Seq), as well as RNA expression (RNA-Seq) before and after membrane depolarization via application of extracellular potassium.
2010-04-14 | E-GEOD-21161 | biostudies-arrayexpress
Project description:Acute leukemia are characterized by deregulation of transcriptional networks that control the lineage specificity of gene expression. The aberrant overexpression of the Spi-1/PU.1 transcription factor leads to erythroleukemia. To determine how Spi-1 mechanistically influences the transcriptional program, we combined a ChIP-seq analysis with transcriptional profiling in cells from an erythroleukemic mouse model. We show that Spi-1 displays a selective DNA-binding that does not often cause transcriptional modulation. We report that Spi-1 controls transcriptional activation and repression through distinct Spi-1 recruitment to chromatin. We revealed several parameters impacting on Spi-1-mediated transcriptional activation. Gene activation is facilitated by Spi-1 occupancy close to transcriptional starting site of genes devoid of CGIs. Moreover, in those regions Spi-1 acts by binding to multiple motifs tightly clustered and with similar orientation. Finally, in contrast to the myeloid and lymphoid B cells in which Spi-1 exerts a physiological activity, in the erythroleukemic cells, lineage-specific cooperating factors do not play a prevalent role in Spi-1-mediated transcriptional activation. Thus, our work describes a new mechanism of gene activation through clustered site occupancy of Spi-1 particularly relevant in regard to the strong expression of Spi-1 in the erythroleukemic cells. Chromatin immunoprecipitations of Spi-1, H3K36me3, RNApolII,mouse IgG followed by sequencing were performed on spleen-derived erythroleukemic cells of spi-1 transgenic mice. In case of Spi-1, reads obtained from the two different mice represent biological replicates and were merged for bioinformatic analysis. Input DNA from each ChIP experiments have been pooled and sequenced as one control.
2012-06-30 | E-GEOD-33611 | 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.M-BM- We have determined the underlyingM-BM- mechanisms by measuring nascent RNA transcription around the clock in mouse liver. Unbiased examination of eRNAs that cluster in specific circadian phasesM-BM- 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 genomicM-BM- analysesM-BM- 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. Nascent RNA transcripts in mouse liver were profiled at 8 time points of the 24 hour light-dark cycle. Static state mRNAs in WT and Rev-erbA -/- mice were profiled using microarray (GSE59460).
2014-11-21 | E-GEOD-59486 | biostudies-arrayexpress
Project description:Microarray-based enrichment of selected genomic loci is a powerful method for genome complexity reduction. Since the vast majority of exons in vertebrate genomes are smaller than 150 nt, we have explored the use of short fragment libraries (85-110bp) to achieve higher enrichment specificity by reducing carryover and adverse effects of flanking intronic sequences. These short fragment libraries were enriched for 1.69 Mb of exonic sequences, using custom 244K microarrays, and sequenced using AB/SOLiD. High enrichment specificity (60 M-bM-^@M-^S 75%) was obtained at 67-213x average coverage, with 77-92% and 90-98% of targeted regions covered with more than 25% and 10% of the average coverage, respectively. As a more appropriate measure of the evenness of coverage, which is relatively independent of sequencing depth, we introduce the evenness of coverage parameter E. E values up to 75% were achieved. To verify the accuracy of SNP/mutation detection we evaluated 384 known non-reference SNPs in the targeted regions. At ~ 200x average sequence coverage, we were able to survey 96.4% of 1.69 Mb of genomic sequence with only 4.2% false negative calls while 3.6% of targeted regions were marked as unsurveyed. A total of 1197 new variants were detected. Verification revealed only 8 false positive calls, resulting in an overall false positive rate of less than 1 per ~200,000 bp (0.0005%, equivalent to an overall phred score of 55). 4 samples + capture design file
2010-02-01 | E-GEOD-18542 | biostudies-arrayexpress
Project description:Transposable elements (TE) have been shown to contrain functional transcription factor (TF) binding sites for long, but the extent to which TEs contribute TF binding sites is not well know. Here, we comprehensively mapped binding sites for 26 pairs of orthologous TFs, in two pairs of human and mouse cell lines (i.e., leukemia, and lymphoblast), along with epigenomic profiles representing DNA methylation and six histone modifications. We found that on average, 20% of TF binding sites were embedded in TEs. We further identified 710 TF-TE relationships in which certain TE subfamilies enriched for TF binidng sites. TE-derived TF binding peaks were also strongly associated with decreased DNA methylation and increased enhancer-associated histone marks. Most of the TE-derived TF binding sites were species-specific, but we also identified conserved binding sites. Additionally, 66% of TE-derived TF binding events were cell-type specific, associated with cell-type specific epigenetic landscape. For data usage terms and conditions, please refer to http://www.genome.gov/27528022 and http://www.genome.gov/Pages/Research/ENCODE/ENCODEDataReleasePolicyFinal2008.pdf To evaluate the contribution of transposable elements (TE) to transcription factor (TF) binding landscapes, we profiled ChIP-seq datasets for 26 TFs in two cell lines in human and mouse, generated by the ENCODE and MouseENCODE consortia. The epigenomic profiles were evaluated from six histone modification in each of the cell lines, also generated by the consortia. We added DNA methylation to the epigenomic profiles, using two complementary techniques, MeDIP-seq and MRE-seq. The mouse data related to this study are available through GSE57230: http://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE57230
2014-05-09 | E-GEOD-56774 | biostudies-arrayexpress
Project description:Transposable elements (TE) have been shown to contrain functional transcription factor (TF) binding sites for long, but the extent to which TEs contribute TF binding sites is not well know. Here, we comprehensively mapped binding sites for 26 pairs of orthologous TFs, in two pairs of human and mouse cell lines (i.e., leukemia, and lymphoblast), along with epigenomic profiles representing DNA methylation and six histone modifications. We found that on average, 20% of TF binding sites were embedded in TEs. We further identified 710 TF-TE relationships in which certain TE subfamilies enriched for TF binidng sites. TE-derived TF binding peaks were also strongly associated with decreased DNA methylation and increased enhancer-associated histone marks. Most of the TE-derived TF binding sites were species-specific, but we also identified conserved binding sites. Additionally, 66% of TE-derived TF binding events were cell-type specific, associated with cell-type specific epigenetic landscape. For data usage terms and conditions, please refer to http://www.genome.gov/27528022 and http://www.genome.gov/Pages/Research/ENCODE/ENCODEDataReleasePolicyFinal2008.pdf To evaluate the contribution of transposable elements (TE) to transcription factor (TF) binding landscapes, we profiled ChIP-seq datasets for 26 TFs in two cell lines in human and mouse, generated by the ENCODE and MouseENCODE consortia. The epigenomic profiles were evaluated from six histone modification in each of the cell lines, also generated by the consortia. We added DNA methylation to the epigenomic profiles, using two complementary techniques, MeDIP-seq and MRE-seq. The human data related to this study are available through GSE56774: http://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE56774
2014-05-09 | E-GEOD-57230 | biostudies-arrayexpress
Project description:AB SOLID sequencing of ribosome-depleted RNA from S. Cerevisiae, S. Paradoxus, S. Mikatae, and S. Bayanus These four yeast species were grown in complete media and total RNA was sequenced. Cross-Species Gene Expression using RNA-Seq Data was examined. Eight samples examined: two biological replicates of each species
2011-12-31 | E-GEOD-32679 | biostudies-arrayexpress
Project description:Our system recapitulates expected characteristics of the well characterized H3.3 histone variant, and show that we gain additional information by using a kinetic approach. Additionaly, our results on the less-studied MacroH2A2 variant revealed differential dynamic profiles of this M-bM-^@M-^\repressiveM-bM-^@M-^] histone variant. Our results represent a novel approach to histone dynamics in mammalian cells, reveal unanticipated dynamic behavior of the MacroH2A2 variant in pluripotent cells, and provide a resource for future studies of tissuespecific histone dynamics in vivo. We use a pulse-chase strategy for carrying out genome-wide measurements of histone dynamics to several histone variants in murine embryonic stem cells and somatic tissues. Genomic binding profiles of histone dynamics in normal ES cells, along with their differentiated counter parts, in MEFs, determined by ChIP-seq.
2014-08-08 | E-GEOD-57665 | biostudies-arrayexpress