Project description:We revealed a close positive relationship between Ptrf transcription and adipose mass in mice, and single-nucleus transcriptomics indicated the involment of impariment of adipogenic differentiation, adipocyte metabolism, transportation of multiple nutrients and altered regulatory network in Ptrf knockout-induced decrease of fat mass.
Project description:Enhancers are developmentally-controlled transcriptional regulatory regions whose activities are modulated through histone modifications or histone variant deposition. Here, we show by genome-wide mapping that the newly discovered DNA modification 5-hydroxymethylcytosine (5hmC) is dynamically associated with transcription factor binding to distal regulatory sites during neural differentiation of mouse P19 cells as well as during adipocyte differentiation of mouse 3T3-L1 cells. Functional annotation reveals that regions gaining 5hmC are associated with genes expressed either in neural tissues when P19 cells undergo neural differentiation or in adipose tissue when 3T3-L1 cells undergo adipocyte differentiation. Furthermore, distal regions gaining 5hmC together with H3K4me2 and H3K27ac in P19 cells behave as differentiation-dependent transcriptional enhancers. Identified regions are enriched in motifs for transcription factors regulating specific cell fates like Meis1 in P19 cells and PPARgamma in 3T3-L1 cells. Accordingly, a fraction of hydroxymethylated Meis1 sites were associated with a dynamic engagement of the 5mC hydroxylase Tet1. In addition, kinetic studies of cytosine hydroxymethylation of selected enhancers indicated that DNA hydroxymethylation is an early event of enhancer activation. Hence, acquisition of 5hmC in cell-specific distal regulatory regions may represent a major event of enhancer progression toward an active state and participate in selective activation of tissue-specific genes MEIS1 and H3K27ac genome-wide distributions were determined using ChIP-seq. Cells used in this study are P19.6 mouse embryonal carnicoma cells and P19.6 cells treated for 48 hours with 1M-BM-5M all-trans retinoic acid (RA). ChIP samples were done by SM-CM-)randour A.A. Libraries were prepared and sequenced by the IGBMC sequencing facility (Strasbourg, France) by an Illumina Genome Analyzer II.
Project description:Enhancers are developmentally-controlled transcriptional regulatory regions whose activities are modulated through histone modifications or histone variant deposition. Here, we show by genome-wide mapping that the newly discovered DNA modification 5-hydroxymethylcytosine (5hmC) is dynamically associated with transcription factor binding to distal regulatory sites during neural differentiation of mouse P19 cells as well as during adipocyte differentiation of mouse 3T3-L1 cells. Functional annotation reveals that regions gaining 5hmC are associated with genes expressed either in neural tissues when P19 cells undergo neural differentiation or in adipose tissue when 3T3-L1 cells undergo adipocyte differentiation. Furthermore, distal regions gaining 5hmC together with H3K4me2 and H3K27ac in P19 cells behave as differentiation-dependent transcriptional enhancers. Identified regions are enriched in motifs for transcription factors regulating specific cell fates like Meis1 in P19 cells and PPARgamma in 3T3-L1 cells. Accordingly, a fraction of hydroxymethylated Meis1 sites were associated with a dynamic engagement of the 5mC hydroxylase Tet1. In addition, kinetic studies of cytosine hydroxymethylation of selected enhancers indicated that DNA hydroxymethylation is an early event of enhancer activation. Hence, acquisition of 5hmC in cell-specific distal regulatory regions may represent a major event of enhancer progression toward an active state and participate in selective activation of tissue-specific genes Genome-wide 5hmC distribution was determined using hMeDIP-seq. Cells used in this study are P19.6 mouse embryonal carnicoma cells and P19.6 cells treated for 48 hours with 1M-BM-5M all-trans retinoic acid (RA), as well as 3T3-L1 cells and 3T3-L1 derived adipocytes differentiated with dexamethasone, insulin and IBMX (differentiation cocktail - DC). Individual hMeDIP samples from P19.6 ord 3T3-L1 cells were pooled for library preparation. Libraries were prepared and sequenced at the IBL sequencing facility (Lille, France) with an Illumina Genome Analyser II.
Project description:Muscular dystrophy is a group of diseases that cause progressive weakness and degeneration of the skeletal muscles that control movement. Lacking the caveolae component polymerase I transcription release factor (PTRF) causes a secondary deficiency of caveolins resulting in muscular dystrophy. To investigate the effect of PTRF deletion on skeletal muscle, we created gene-edited mice with PTRF knockout (KO). We then performed RNA-seq of soleus and quadriceps muscles from soleus and quadriceps muscles of 3 months old WT (n=3) and PTRF KO mice (n=3) and analyzed the data for gene expression profiling. 12933 genes were detected across all 12 libraries. The hierarchy clustering of co-expressed genes revealed a clear split between PTRF KO and WT mice for both skeletal muscles. Differential expression analysis identified 1293 and 705 differentially expressed genes (DEGs) in the soleus and quadriceps, respectively. 971 and 534 DEGs were up-regulated, and 322 and 171 DEGs were down-regulated in the soleus and quadriceps of PTRF KO mice, respectively.
Project description:The transcription factor MYC is overexpressed in most cancers, where it drives multiple hallmarks of cancer progression. MYC is known to promote oncogenic transcription by binding to active promoters. In addition, MYC has also been shown to invade distal enhancers when expressed at oncogenic levels, but this enhancer binding has been proposed to have low gene-regulatory potential. Here, we demonstrate that MYC enhancer binding directly promotes cancer type-specific gene programs predictive of poor patient prognosis. MYC induces transcription of enhancer RNA through recruitment of RNAPII, rather than regulating RNAPII pause-release as is the case at promoters. This is mediated by MYC-induced H3K9 demethylation by KDM3A and acetylation by GCN5, leading to enhancer-specific BRD4 recruitment through its bromodomains, which facilitates RNAPII recruitment. Thus, we propose that MYC drives prognostic cancer type-specific gene programs by promoting RNAPII recruitment to enhancers through induction of an epigenetic switch.
Project description:High-fat diet and obesity are high risk factors for colorectal cancer. The underlying mechanism is still unclear. Environmental factors alter the epigenome to affect gene expression thus the phenotype. In response to external stimuli, the cis-regulatory regions, especially enhancer loci, are key elements for regulating selective gene expression. We thus explored the effects of high-fat diet and the accompanying obesity on gene expression and the enhancer landscape in colon epithelium. High-fat diet exposed binding sites of transcription factors downstream of signaling pathways important in the initiation and progression of colon cancer. Meantime, colon specific enhancers were lost rendering the cells potential for dedifferentiation. The alteration at enhancer regions drives a specific transcription program promoting colon cancer progression. The comprehensive interrogation of enhancer changes by high-fat diet in colon epithelium provides a number of insights into the underlying biology of high-fat diet and obesity in increasing colon cancer risk, and provides potential therapeutic targets to treat obese colon cancer patients. ChIP sequencing of active enhancer mark h3k27ac in colon epithelium from wild type mice and NAG-1 transgenic mice treated with either low-fat diet or high-fat diet. The gene expression component of the study is included in GSE46843.
Project description:Cellular senescence is a tumor-suppressive program that involves chromatin reorganization and specific changes in gene expression that trigger an irreversible cell-cycle arrest. We combined quantitative mass spectrometry and ChIP deep-sequencing to identify changes in histone modification occurring during cellular senescence. ChIP-seq was carried out using H3K4me3-specific antibodies in growing, quiescent, senescent, or senescent with shRB targeting Rb, IMR90 cells. The control mock data (ChIP-seq using anti-mouse IgG antibody) is available in GEO Sample GSM497500 (Series GSE19898).
Project description:Enhancers are developmentally-controlled transcriptional regulatory regions whose activities are modulated through histone modifications or histone variant deposition. Here, we show by genome-wide mapping that the newly discovered DNA modification 5-hydroxymethylcytosine (5hmC) is dynamically associated with transcription factor binding to distal regulatory sites during neural differentiation of mouse P19 cells as well as during adipocyte differentiation of mouse 3T3-L1 cells. Functional annotation reveals that regions gaining 5hmC are associated with genes expressed either in neural tissues when P19 cells undergo neural differentiation or in adipose tissue when 3T3-L1 cells undergo adipocyte differentiation. Furthermore, distal regions gaining 5hmC together with H3K4me2 and H3K27ac in P19 cells behave as differentiation-dependent transcriptional enhancers. Identified regions are enriched in motifs for transcription factors regulating specific cell fates like Meis1 in P19 cells and PPARgamma in 3T3-L1 cells. Accordingly, a fraction of hydroxymethylated Meis1 sites were associated with a dynamic engagement of the 5mC hydroxylase Tet1. In addition, kinetic studies of cytosine hydroxymethylation of selected enhancers indicated that DNA hydroxymethylation is an early event of enhancer activation. Hence, acquisition of 5hmC in cell-specific distal regulatory regions may represent a major event of enhancer progression toward an active state and participate in selective activation of tissue-specific genes A 6-chip study aiming to characterize regulated genes in P19.6 mouse embryonal carcinoma cells following 48 hours treatment with 1M-BM-5M all-trans retinoic acid. RNAs were prepared from three independent triplicate experiments.
Project description:The functional organization of eukaryotic genomes correlates with specific patterns of histone methylations. Regulatory regions in genomes like enhancers and promoters differ in their extent of methylation of histone H3 at lysine-4 (H3K4), but it is largely unknown how the different methylation states are specified and controlled. Here, we show that the Kdm5c/Jarid1c/SMCX member of the Kdm5 family of H3K4 demethylases can be recruited to both enhancer and promoter elements in embryonic stem cells and neuronal progenitor cells via gene-specific transcription factors. Knockdown of Kdm5c deregulates transcription via local increases in H3K4me3. Our data show that restricting H3K4me3 modification at core promoters dampens transcription, but Kdm5c is required at enhancers for their full activity. Remarkably, an impaired enhancer function activates the intrinsic promoter activity of Kdm5c-bound distal elements. Our results demonstrate that the Kdm5c demethylase plays a crucial and dynamic role in the functional discrimination between enhancers and core promoters. RNA from four independent cultures from each sh Kdm5c #1, sh Kdm5c #2 and non-targeting shRNA polyclonal cell lines were hybridized in dye-swap against a common reference of RNA from IB10 ES cells.