Characterization of chromatin and gene expression changes during fasting in mouse liver [ChIP-Seq]
Ontology highlight
ABSTRACT:
ORGANISM(S): Mus musculus
PROVIDER: GSE72084 | GEO | 2016/12/20
SECONDARY ACCESSION(S): PRJNA292913
REPOSITORIES: GEO
Similar Datasets
Project description:During fasting the liver supplies the organism’s energy demands by producing glucose and ketones. Fuel production during fasting is temporally organized whereby glucose serves as the major fuel produced in short-term fasting while ketones are produced in longer fasts as gluconeogenic precursors deplete1. However, the regulatory process dictating this temporally-organized metabolic output is unexplored. Here we show that a cascade of transcription factors (TFs) sequentially activated by hormonal signals, TF gene expression and assisted loading onto specific ‘fasting enhancers’ generate a framework for the temporal organization of fuel production during fasting. Fasting led to massive chromatin re-organization, exposing enhancers in which a complex set of regulatory signals converge to regulate transcription. Glucagon secreted in early fasting activates cAMP responsive element binding protein (CREB) leading to increased expression of many TF genes, including CCAAT enhancer binding protein β (C/EBPβ) which relaxes chromatin, thereby potentiating glucocorticoid receptor (GR) binding to fasting enhancers upon its activation by corticosterone in mid-term fasting. Then, GR augments glucagon-dependent gluconeogenesis but also supports a peroxisome proliferator receptor α (PPARα)-dependent ketogenic gene program to sustain ketogenesis during prolonged fasting. Our results bridge over a long-lasting gap between the characterized temporal organization of fuel output during fasting and the undefined role of transcription and chromatin regulation in generating this output. Because a de-regulated response to fasting is a hallmark of diabetes progression, these findings may promote our understanding of this complex disease
2016-12-20 | GSE72085 | GEO
Project description:During fasting the liver supplies the organism’s energy demands by producing glucose and ketones. Fuel production during fasting is temporally organized whereby glucose serves as the major fuel produced in short-term fasting while ketones are produced in longer fasts as gluconeogenic precursors deplete1. However, the regulatory process dictating this temporally-organized metabolic output is unexplored. Here we show that a cascade of transcription factors (TFs) sequentially activated by hormonal signals, TF gene expression and assisted loading onto specific ‘fasting enhancers’ generate a framework for the temporal organization of fuel production during fasting. Fasting led to massive chromatin re-organization, exposing enhancers in which a complex set of regulatory signals converge to regulate transcription. Glucagon secreted in early fasting activates cAMP responsive element binding protein (CREB) leading to increased expression of many TF genes, including CCAAT enhancer binding protein β (C/EBPβ) which relaxes chromatin, thereby potentiating glucocorticoid receptor (GR) binding to fasting enhancers upon its activation by corticosterone in mid-term fasting. Then, GR augments glucagon-dependent gluconeogenesis but also supports a peroxisome proliferator receptor α (PPARα)-dependent ketogenic gene program to sustain ketogenesis during prolonged fasting. Our results bridge over a long-lasting gap between the characterized temporal organization of fuel output during fasting and the undefined role of transcription and chromatin regulation in generating this output. Because a de-regulated response to fasting is a hallmark of diabetes progression, these findings may promote our understanding of this complex disease
2016-12-20 | GSE72086 | GEO
Project description:During fasting, bodily homeostasis is maintained due to hepatic production of glucose (via gluconeogenesis) and ketone bodies (via ketogenesis). The major hormones governing hepatic fuel production are glucagon and glucocorticoids who initiate a complex transcriptional program aimed at supporting gluconeogenesis and ketogenesis. Here, we found that in addition to the known metabolic genes induced by glucagon and glucocorticoids, these hormones each induce a set of genes encoding transcription factors (TFs) thereby initiating transcriptional cascades. Glucocorticoids activate the glucocorticoid receptor (GR) that induces the genes encoding two TFs - C/EBPβ and PPARα. Transcriptomic analysis combined with gene silencing revealed the role of C/EBPβ as an amplifier of hormone-induced gluconeogenesis. In contrast, the GR-PPARα cascade initiated a secondary transcriptional wave of genes supporting ketogenesis. We show that a dual treatment of glucocorticoids with a PPARα agonist leads to synergistic induction of ketogenic genes and that this induction is dependent on protein synthesis. Genome-wide analysis of enhancer dynamics revealed numerous enhancers activated by the GR-PPARα cascade. These enhancers are proximal to ketogenic genes, are enriched for the PPARα binding motif and show increased PPARα binding as profiled by ChIP-seq. In summary, this study reveals abundant TF cascades occurring during fasting. These cascades serve two separated purposes: the amplification of the primary gluconeogenic transcriptional program and the induction of a secondary gene program aimed at enhancing ketogenesis.
2024-08-18 | GSE252319 | GEO
Project description:During fasting, bodily homeostasis is maintained due to hepatic production of glucose (via gluconeogenesis) and ketone bodies (via ketogenesis). The major hormones governing hepatic fuel production are glucagon and glucocorticoids who initiate a complex transcriptional program aimed at supporting gluconeogenesis and ketogenesis. Here, we found that in addition to the known metabolic genes induced by glucagon and glucocorticoids, these hormones each induce a set of genes encoding transcription factors (TFs) thereby initiating transcriptional cascades. Glucocorticoids activate the glucocorticoid receptor (GR) that induces the genes encoding two TFs - C/EBPβ and PPARα. Transcriptomic analysis combined with gene silencing revealed the role of C/EBPβ as an amplifier of hormone-induced gluconeogenesis. In contrast, the GR-PPARα cascade initiated a secondary transcriptional wave of genes supporting ketogenesis. We show that a dual treatment of glucocorticoids with a PPARα agonist leads to synergistic induction of ketogenic genes and that this induction is dependent on protein synthesis. Genome-wide analysis of enhancer dynamics revealed numerous enhancers activated by the GR-PPARα cascade. These enhancers are proximal to ketogenic genes, are enriched for the PPARα binding motif and show increased PPARα binding as profiled by ChIP-seq. In summary, this study reveals abundant TF cascades occurring during fasting. These cascades serve two separated purposes: the amplification of the primary gluconeogenic transcriptional program and the induction of a secondary gene program aimed at enhancing ketogenesis.
2024-08-18 | GSE252318 | GEO
Project description:During fasting, bodily homeostasis is maintained due to hepatic production of glucose (via gluconeogenesis) and ketone bodies (via ketogenesis). The major hormones governing hepatic fuel production are glucagon and glucocorticoids who initiate a complex transcriptional program aimed at supporting gluconeogenesis and ketogenesis. Here, we found that in addition to the known metabolic genes induced by glucagon and glucocorticoids, these hormones each induce a set of genes encoding transcription factors (TFs) thereby initiating transcriptional cascades. Glucocorticoids activate the glucocorticoid receptor (GR) that induces the genes encoding two TFs - C/EBPβ and PPARα. Transcriptomic analysis combined with gene silencing revealed the role of C/EBPβ as an amplifier of hormone-induced gluconeogenesis. In contrast, the GR-PPARα cascade initiated a secondary transcriptional wave of genes supporting ketogenesis. We show that a dual treatment of glucocorticoids with a PPARα agonist leads to synergistic induction of ketogenic genes and that this induction is dependent on protein synthesis. Genome-wide analysis of enhancer dynamics revealed numerous enhancers activated by the GR-PPARα cascade. These enhancers are proximal to ketogenic genes, are enriched for the PPARα binding motif and show increased PPARα binding as profiled by ChIP-seq. In summary, this study reveals abundant TF cascades occurring during fasting. These cascades serve two separated purposes: the amplification of the primary gluconeogenic transcriptional program and the induction of a secondary gene program aimed at enhancing ketogenesis.
2024-08-18 | GSE252317 | GEO
Project description:Metabolic homeostasis in mammals critically depends on the regulation of fasting-induced genes by CREB in the liver. Previous genome-wide analysis has shown that only a small percentage of CREB target genes are induced in response to fasting-associated signaling pathways. The precise molecular mechanisms by which CREB specifically targets these genes in response to alternating hormonal cues remain to be elucidated. We performed chromatin immunoprecipitation coupled to high-throughput sequencing of CREB in livers from both fasted and re-fed mice. In order to quantitatively compare the extent of CREB-DNA interactions genome-wide between these two physiological conditions we developed a novel, robust analysis method, termed the M-bM-^@M-^Xsingle sample independenceM-bM-^@M-^Y (SSI) test that greatly reduced the number of false positive peaks. We found that CREB remains constitutively bound to its target genes in the liver regardless of the metabolic state. Integration of the CREB cistrome with expression microarrays of fasted and re-fed mouse livers and ChIP-seq data for additional transcription factors revealed that the gene expression switches between the fasted and fed states are associated with co-localization of additional transcription factors at CREB sites. Our results support a model in which CREB is constitutively bound to thousands of potential target genes and combinatorial interactions between DNA-binding factors are necessary to achieve the specific transcriptional response of the liver to fasting. Furthermore, our genome-wide analysis identifies thousands of novel CREB target genes in liver, including a previously unknown role for CREB in regulating ER stress genes in response to nutrient influx. CREB ChIP-seq was performed on mouse liver from fasted and re-fed mice, using 5 separate biological replicates for each condition. GR and C/EBP(beta) ChIP-seq were performed as single replicates on ad-lib fed mice.
2013-05-01 | E-GEOD-45674 | biostudies-arrayexpress
Project description:Glucocorticoid receptor (GR) is an essential transcription factor (TF), controlling metabolism, development and immune responses. SUMOylation regulates chromatin occupancy and target gene expression of GR in a locus-selective manner, but the mechanism of regulation has remained elusive. Here, we show using selective isolation of chromatin-associated proteins that the protein network around chromatin-bound GR is affected by SUMOylation, with several nuclear receptor coregulators and chromatin modifiers being more avidly associated with SUMOylation-deficient than SUMOylation competent GR. This difference is reflected in our chromatin accessibility and gene expression data, showing that the SUMOylation-deficient GR is more potent in opening chromatin at glucocorticoid-regulated enhancers and inducing expression of their target loci. Our results thus show that SUMOylation determines GR specificity by regulating the chromatin protein network and accessibility at GR-driven enhancers. We speculate that a similar mechanism is utilized by many other SUMOylated TFs.
2021-09-08 | PXD015183 | Pride
Project description:The discovery of FoxO1 as an effector of insulin action on gene expression filled a gap in our knowledge of insulin signaling. The metabolic impact of hepatic FoxO1 has been demonstrated in genetic mouse models showing that FoxO1 inhibition can reverse diabetes. However, the gamut of FoxO1 targets is unknown, due to the lack of robust genome-wide chromatin occupancy data. To elucidate the genomic architecture of the FoxO1 effect on liver metabolism, we integrated genome-wide ChIP-seq and RNA-seq. During the physiological transition from fasting to refeeding, hepatic FoxO1 translocated from the nucleus to the cytoplasm. At the same time points, cistrome analysis demonstrated that 60% of FoxO1 target sites were cleared by refeeding. RNA-seq from mice following acute liver-specific FoxO1 ablation allowed us to integrate the data in a comprehensive FoxO1 regulome. We identified four distinct classes of FoxO1 targets. Class I targets are enriched in genes regulating cell homeostasis, have FoxO1 sites clustered in promoters and do not show regulation with fasting/refeeding. Class II is comprised of canonical FoxO1 metabolic targets coordinately regulated with other fasting-inducible TFs, such as PPARA, CREB, and GR through promoters. Class III is enriched in glucose metabolic genes regulated through active enhancers, as detected by H3K4me1 and H3K27ac histone marks. Class IV is comprised of triglyceride (TG) and lipoprotein metabolism genes, regulated through intron sites, and characterized by an uneven response to fasting/refeeding regulation.
2022-05-24 | GSE151545 | GEO
Project description:The discovery of FoxO1 as an effector of insulin action on gene expression filled a gap in our knowledge of insulin signaling. The metabolic impact of hepatic FoxO1 has been demonstrated in genetic mouse models showing that FoxO1 inhibition can reverse diabetes. However, the gamut of FoxO1 targets is unknown, due to the lack of robust genome-wide chromatin occupancy data. To elucidate the genomic architecture of the FoxO1 effect on liver metabolism, we integrated genome-wide ChIP-seq and RNA-seq. During the physiological transition from fasting to refeeding, hepatic FoxO1 translocated from the nucleus to the cytoplasm. At the same time points, cistrome analysis demonstrated that 60% of FoxO1 target sites were cleared by refeeding. RNA-seq from mice following acute liver-specific FoxO1 ablation allowed us to integrate the data in a comprehensive FoxO1 regulome. We identified four distinct classes of FoxO1 targets. Class I targets are enriched in genes regulating cell homeostasis, have FoxO1 sites clustered in promoters and do not show regulation with fasting/refeeding. Class II is comprised of canonical FoxO1 metabolic targets coordinately regulated with other fasting-inducible TFs, such as PPARA, CREB, and GR through promoters. Class III is enriched in glucose metabolic genes regulated through active enhancers, as detected by H3K4me1 and H3K27ac histone marks. Class IV is comprised of triglyceride (TG) and lipoprotein metabolism genes, regulated through intron sites, and characterized by an uneven response to fasting/refeeding regulation.
2022-05-24 | GSE151544 | GEO
Project description:The Glucocorticoid Receptor (GR) is a potent metabolic regulator and a major drug target. While GR was shown to play various important roles in circadian biology, its rhythmic genomic actions have never been studied. Here we mapped GR’s genome-wide chromatin occupancy in mouse livers throughout the day/night cycle. We show how GR partitions metabolic processes during fasting (cellular maintenance, gluconeogenesis) and feeding (lipid and amino acid metabolism) by time-dependent binding and target gene regulation. Highlighting the dominant role GR plays in synchronizing circadian pathways, we find that the majority of oscillating genes harbor GR binding sites and depend on GR for amplitude stability . Surprisingly, this rhythmic pattern is altered by exposure to high fat diet in a ligand-independent manner. We show how the remodeling of oscillatory gene expression and GR binding result from a concomitant increase with Stat5 co-occupancy in obese mice, and that loss of GR reduces circulating glucose and triglycerides differentially during feeding and fasting. Altogether, our findings highlight GR’s fundamental role in the rhythmic orchestration of hepatic metabolism.
2019-10-24 | PXD014030 | Pride