Regulation of Glucose Uptake and Inflammation by FOXO1 and FOXO3 in Skeletal Muscle
Ontology highlight
ABSTRACT:
ORGANISM(S): Mus musculus
PROVIDER: GSE105778 | GEO | 2018/12/10
REPOSITORIES: GEO
Similar Datasets
Project description:Forkhead Box O (FOXO) transcription factors are versatile players in diverse cellular processes, affecting tumorigenesis, metabolism, stem cell maintenance and lifespan. To understand the transcriptional output of FOXO3 activation, we investigate features that define the subset of enhancer binding events that actually contribute to gene regulation. We show FOXO3 transcriptional output is determined by the amount of bound FOXO3, which in turn is determined by motif presence, pre-existing enhancer activity and accessibility. In this manner, FOXO3 amplifies pre-existing levels of activity marks and potentiates enhancer RNA transcription. We conclude that not only enhancer presence and sequence content, but also the pre-existing activity dictates FOXO3 binding and transcriptional output. Considering the flexible and cell type specific nature of regulatory regions and their activity, our observations provide a novel explanation for the diversity in FOXO transcriptional programs and introduce chromatin context as a new player in the regulation of FOXO activity in ageing and disease. Examination of histone modifications and transcriptome changes upon FOXO activation
2013-11-26 | E-GEOD-50243 | biostudies-arrayexpress
Project description:Aims/hypothesis: While lipid deposition in skeletal muscle is considered to be involved in obesity-associated insulin resistance, neutral intramyocellular lipid (IMCL) accumulation per se does not necessarily induce insulin resistance. We previously demonstrated that overexpression of the lipid droplet coat protein perilipin 2 augments intramyocellular lipid content while improving insulin sensitivity. Another member of the perilipin family, perilipin 5 (PLIN5), is predominantly expressed in oxidative tissues like skeletal muscle. Here we investigated the effects of PLIN5 overexpression M-bM-^@M-^S in comparison with effects of PLIN2 M-bM-^@M-^S on skeletal muscle lipid levels, gene expression profiles and insulin sensitivity. Methods: Gene electroporation was used to overexpress PLIN5 in tibialis anterior muscle of rats fed a high fat diet. Eight days after electroporation, insulin-mediated glucose uptake in skeletal muscle was measured by means of a hyperinsulinemic euglycemic clamp. Electron microscopy, fluorescence microscopy and lipid extractions were performed to investigate IMCL accumulation. Gene expression profiles were obtained using microarrays. Results: TAG storage and lipid droplet size increased upon PLIN5 overexpression. Despite the higher IMCL content, insulin sensitivity was not impaired and DAG and acylcarnitine levels were unaffected. In contrast to the effects of PLIN2 overexpression, microarray data analysis revealed a gene expression profile favoring FA oxidation and improved mitochondrial function. Conclusions/interpretation: Both PLIN2 and PLIN5 increase neutral IMCL content without impeding insulin-mediated glucose uptake. As opposed to the effects of PLIN2 overexpression, overexpression of PLIN5 in skeletal muscle promoted expression of a cluster of genes under control of PPARM-NM-1 and PGC1M-NM-1 involved in FA catabolism and mitochondrial oxidation. Rats received a high fat diet for 3 weeks; 2 weeks after start of the diet intervention Plin5 (OXPAT) or Plin2 (ADRP) were overexpressed in either the right or left tibialis anterior muscle. One week later pooled tibialis anterior muscle samples were analysed on microarrays.
2013-01-29 | E-GEOD-43832 | biostudies-arrayexpress
Project description:FOXO transcription factors are key players in diverse cellular responses affecting tumorigenesis, stem cell maintenance and lifespan. To gain insight into mechanisms of FOXO regulated gene expression, we studied genome-wide effects of FOXO3 activation. Profiling RNA polymerase II (RNAPII) changes shows FOXO3 regulates gene expression through transcription initiation. Correlative analysis of FOXO3 and RNAPII ChIP-seq profiles demonstrates FOXO3 to act as a transcriptional activator. Furthermore, this analysis reveals a significant part of FOXO3 gene regulation proceeds through enhancer regions. FOXO3 binds to and activates enhancers as shown by the presence of and changes in enhancer-specific histone modifications and RNAPII occupancy. In addition, FOXO3-mediated enhancer regulation correlates with regulation of adjacent genes and existence of chromatin loops between FOXO3 bound enhancers and regulated genes. Combined, our data elucidate how FOXOs regulate gene transcription and provide insight into mechanisms by which FOXOs can induce different gene expression programs depending on chromatin architecture.
2012-12-30 | GSE36835 | GEO
Project description:The mammalian FoxO transcription factors - FoxO1, FoxO3, FoxO4 - function in the nucleus to direct transcription of specific gene targets governing cellular survival, proliferation, metabolism, differentiation and oxidative defense. Activation of PI3K by extracellular growth factors leads to AKT-mediated phosphorylation of FoxO1, FoxO3 and FoxO4, resulting in their sequestration in the cytoplasm such that they are unable to regulate their gene targets. Our study identified FoxOs as novel tumor suppressors in kidney cancer (Gan et al, 2010, Cancer Cell). To understand the tumor suppression function of FoxOs in kidney cancer cells, we performed gene expression profiling in human kidney cancer cells upon FoxO1 or FoxO3 reactivation in order to identify the key transcriptomic alterations mediating FoxO tumor suppression function in kidney cancer cells. We generated RCC4 and UMRC2 cell lines (two human kidney cancer cells with low endogenous FoxO1 and FoxO3 expression) with stable expression of FoxO1(TA)ERT2 or FoxO3(TA)ERT2 construct, which expressed a fusion protein consisting of FoxO(TA) (containing three Ser/Thr AKT phosphorylation sites mutated to alanine) fused to the T2-modified estrogen receptor (ERT2) moiety. We documented that the FoxO(TA)ERT2 fusion protein sequestered FoxO(TA) in the cytoplasm and that 4OHT treatment resulted in rapid translocation of FoxO(TA)ERT2 into the nucleus. We also established stable cell lines with ERT2 expression as control cell lines. (For simplicity, ERT2, FoxO1(TA)ERT2 and FoxO3(TA)ERT2 cell lines will be referred to as EV (empty vector), FoxO1 and FoxO3, respectively, hereafter). We then conducted comparative transcriptome analysis (using the Human Genome U133 Plus 2.0 Array) of EV, FoxO1, or FoxO3-expressing RCC4 and UMRC2 cells at 12 hours with or without 100 nm 4OHT treatment (cultured in DMEM+10% FBS with puromycin selection). To enrich for more proximal actions of FoxO, we selected the 12 hour time point as time course studies revealed dramatic transcriptional changes of known FoxO targets (such as Cyclin D1), yet no discernable cellular phenotypes (apoptosis and cell cycle arrest). We generated 4 transcriptome datasets: FoxO1 RCC4, FoxO3 RCC4, FoxO1 UMRC2, and FoxO3 UMRC2 (by comparing transcriptome data with or without 4OHT treatment), and normalized these transcriptome data against 4OHT-treated EV cells, which show modest 4OHT-induced transcriptional changes.
2011-10-20 | E-GEOD-23926 | biostudies-arrayexpress
Project description:MuRF1 is a muscle-specific E3 ubiquitin ligase and component of the ubiquitin proteasome system. MuRF1 is transcriptionally upregulated under conditions that cause muscle loss, in both rodents and humans, and is a recognized marker of muscle atrophy. In this study, we used in vivo electroporation to determine if MuRF1 overexpression alone can cause muscle atrophy and, in combination with ubiquitin proteomics, identify the endogenous MuRF1 substrates in skeletal muscle. Tibialis anterior (TA) muscles were transfected with an untagged MuRF1 plasmid or control plasmid for 14 days. A total of 963 ubiquitination sites, corresponding to 250 proteins, were quantified from the TA muscle. Statistical analysis revealed that the overexpression of MuRF1 resulted in significant upregulation of 153 ubiquitination sites on 45 proteins and significant downregulation of 16 sites on 11 proteins. Substrates of MuRF1 include contractile and metabolic proteins, deubiquitinases, p62, and VCP. Moreover, MuRF1-mediated ubiquitination leads to destabilization and breakdown of the sarcomere and reveals a role for MuRF1 in the regulation of additional proteolytic pathways in skeletal muscle.
2021-07-07 | PXD023872 | Pride
Project description:Forkhead Box O (FOXO) transcription factors are versatile players in diverse cellular processes, affecting tumorigenesis, metabolism, stem cell maintenance and lifespan. To understand the transcriptional output of FOXO3 activation, we investigate features that define the subset of enhancer binding events that actually contribute to gene regulation. We show FOXO3 transcriptional output is determined by the amount of bound FOXO3, which in turn is determined by motif presence, pre-existing enhancer activity and accessibility. In this manner, FOXO3 amplifies pre-existing levels of activity marks and potentiates enhancer RNA transcription. We conclude that not only enhancer presence and sequence content, but also the pre-existing activity dictates FOXO3 binding and transcriptional output. Considering the flexible and cell type specific nature of regulatory regions and their activity, our observations provide a novel explanation for the diversity in FOXO transcriptional programs and introduce chromatin context as a new player in the regulation of FOXO activity in ageing and disease.
2013-11-26 | GSE50243 | GEO
Project description:FOXO transcription factors are central regulators of longevity from worms to humans. FOXO3 – the FOXO isoform associated with exceptional human longevity – preserves adult neural stem cell pools. Here we identify FOXO3 direct targets genome-wide in primary cultures of adult neural progenitor cells (NPCs). Interestingly, FOXO3-bound sites are enriched for motifs for bHLH transcription factors and FOXO3 shares common targets with the pro-neuronal bHLH transcription factor ASCL1/MASH1 in NPCs. Analysis of the chromatin landscape reveals that FOXO3 and ASCL1 are particularly enriched at the enhancers of genes involved in neurogenic pathways. Intriguingly, FOXO3 inhibits ASCL1-dependent neurogenesis in NPCs and direct neuronal conversion in fibroblasts. FOXO3 also restrains neurogenesis in vivo. Our study identifies a genome-wide interaction between the pro-longevity transcription factor FOXO3 and the cell fate determinant ASCL1, and raises the possibility that FOXO3’s ability to restrain ASCL1-dependent neurogenesis may help preserve the neural stem cell pool. ChIP-seq profiles of two transcription factors (FOXO3 and ASCL1) and three histone marks (H3K4me1, H3K4me3 and H3K27me3) in adult mouse neural progenitor cells.
2013-08-13 | E-GEOD-48336 | biostudies-arrayexpress
Project description:FOXO transcription factors are key players in diverse cellular responses affecting tumorigenesis, stem cell maintenance and lifespan. To gain insight into mechanisms of FOXO regulated gene expression, we studied genome-wide effects of FOXO3 activation. Profiling RNA polymerase II (RNAPII) changes shows FOXO3 regulates gene expression through transcription initiation. Correlative analysis of FOXO3 and RNAPII ChIP-seq profiles demonstrates FOXO3 to act as a transcriptional activator. Furthermore, this analysis reveals a significant part of FOXO3 gene regulation proceeds through enhancer regions. FOXO3 binds to and activates enhancers as shown by the presence of and changes in enhancer-specific histone modifications and RNAPII occupancy. In addition, FOXO3-mediated enhancer regulation correlates with regulation of adjacent genes and existence of chromatin loops between FOXO3 bound enhancers and regulated genes. Combined, our data elucidate how FOXOs regulate gene transcription and provide insight into mechanisms by which FOXOs can induce different gene expression programs depending on chromatin architecture. seven 4C view point were analyzed on DLD1 colon carcinoma cells containing 4OH-Tamoxifen inducible FOXO3A3-ER (DL23 cells, Kops et al., 2002, Mol Cell Biol), to investigate 3D topology around FOXO3 bound regions and FOXO3 regulated genes before and 4 hours after addition of tamoxifen. 4C procedure, as published before (Splinter et al., 2001, Genes Dev). Cells are cross linked using 1% formaldehyde for 10min at room temperature, nuclei are isolated, after which chromatin is digested with DpnII and subsequently ligated under diluted conditions. After reversal of the cross links the DNA is purified and treated with the second restriction enzyme treatment (Csp). After a second re-ligation step the sample is purified and ligated fragments are analyzed by inverse PCR.
2012-12-30 | E-GEOD-36835 | biostudies-arrayexpress
Project description:Circadian rhythms are responsive to a variety of external cues, light and metabolism being the most important. In mammals, the light signal is sensed by the retina and transmitted to the SCN master clock, where it is translated into the molecular oscillator via regulation of clock gene transcription. The signalling pathways governing the molecular translation from metabolic signals to circadian output in peripheral oscillators, in contrast, are less understood. FOXO transcription factors are known to translate external metabolic cues to internal transcriptional programs. In the past couple of years it has become evident that both FOXO transcription factors and the circadian clock are of key importance in the underlying mechanisms of ageing and the regulation of metabolism. We now show FOXO3 to be a crucial modulator of circadian rhythmicity via direct transcriptional regulation of Clock, a core component of the molecular oscillator, and identify FOXO3 as a novel link in the circadian feedback loop, which is required for circadian rhythms in liver. We propose that FOXO3 directly feeds back into the circadian oscillator in response to metabolic cues. We performed a microarray study on synchronized NIH 3T3 cells upon transient knock-down of FoxO3 (siO3). Cells were harvested for RNA isolation 24h (time1), 30h(time2), 36h(time3) and 42h(time4) after synchronization. Experimental samples were hybridized against a reference pool of cRNA, which was derived from unsynchronized NIH 3T3 cells. AS controlgroup a scrambled siRNA was transfected. Experiments were performed 4 times, of each sample group two samples were labeled with cy5 and co-hybridized with reference RNA labeled with cy3, and two samples were labeled and hybridized in the opposite way. Microarrays used were Mouse Whole Genome Gene Expression Microarrays V1 (Agilent Technologies, Belgium)
2014-06-03 | E-GEOD-41555 | biostudies-arrayexpress
Project description:Forkhead BoxO (FoxO) transcription factors expressed in adult skeletal muscle promote muscle atrophy during various catabolic conditions. We have identified the genome wide target genes and biological networks regulated by FoxO in skeletal muscle during Colon-26 (C-26) cancer cachexia. In this dataset, we include the expression data obtained from the tibialis anterior muscles of control and severely cachectic Colon-26 mice in which FoxO-dependent transcription was either intact (AAV9-EV) or inhibited (AAV9-d.n.FoxO). These data were used to obtain 543 FoxO target genes during cancer. These target genes were identified as those genes whose expression was both differentially regulated in skeletal muscle in response to cancer (control AAV9-EV vs. C26 AAV9-EV), and differentially regulated in the presence of d.n.FoxO (C26 AAV9-EV vs. C26 AAV9-d.n.FoxO).
2014-12-31 | GSE56555 | GEO