A Sensitive Approach to Map Genome-wide 5-Hydroxymethylcytosine and 5-Formylcytosine at Single-base Resolution
Ontology highlight
ABSTRACT:
ORGANISM(S): Mus musculus
SUBMITTER: Shengxi Guan
PROVIDER: E-GEOD-64186 | biostudies-arrayexpress |
REPOSITORIES: biostudies-arrayexpress
Similar Datasets
Project description:DNA methylation at 5-position of cytosine (5mC) is one of the best studied epigenetic modifications that plays important roles in diverse biological processes. Iterative oxidation of 5mC by the Ten-eleven translocation (Tet) family of proteins generates 5-hydroxymethylcytosine (5hmC), 5-formylcytosine (5fC), and 5-carboxylcytosine (5caC), which can be further processed by DNA repair proteins leading to DNA demethylation. Functional characterization of the Tet proteins has been complicated by the redundancy between the three Tet proteins. Using the CRISPR/Cas9 technology, we have generated mouse embryonic stem cells (ESCs) deficient for all three Tet proteins (TKO). Whole genome bisulphite sequencing (WGBS) analysis revealed that Tet-mediated DNA demethylation mainly occurs distal enhancers as well as promoters that significantly overlap with 5hmC, 5fC and 5caC. Characterization of the Tet TKO ESCs revealed a function for Tet proteins in cell fate restriction as Tet TKO ESCs tend to adopt both primed pluripotent stem cell-like state and 2-cell embryo-like state. In addition, Tet TKO ESCs exhibit elongated telomeres. Thus, our study reveals a role of Tet proteins not only in DNA demethylation, but also in cell fate restriction and telomere maintenance. 2 samples for WGBS and 2 samples for RNA-seq
2014-09-22 | E-GEOD-56986 | biostudies-arrayexpress
Project description:TET proteins oxidize 5-methylcytosine (5mC) to 5-hydroxymethylcytosine (5hmC), 5-formylcytosine (5fC), and 5-carboxylcytosine (5caC). 5fC and 5caC are excised by mammalian DNA glycosylase TDG, implicating 5mC oxidation in DNA demethylation. Here we show that the genomic locations of 5fC can be determined by coupling chemical reduction with biotin tagging. Genome-wide mapping of 5fC in mouse embryonic stem cells (mESCs) reveals that 5fC preferentially occurs at poised enhancers among other gene regulatory elements. Application to Tdg null mESCs further suggests that 5fC production coordinates with p300 in remodeling epigenetic states of enhancers. This process, which is not influenced by 5hmC, appears to be associated with further oxidation of 5hmC and commitment to demethylation through 5fC. Finally, we resolved 5fC at base-resolution by hydroxylamine-based protection from bisulfite-mediated deamination, thereby confirming sites of 5fC accumulation. Our results reveal roles of active 5mC/5hmC oxidation and TDG-mediated demethylation in epigenetic tuning at regulatory elements. We report here a chemical labeling method that effectively differentiates 5fC from 5mC, 5hmC, and 5caC in genomic DNA. First, we quantitatively protect endogenous 5hmC with a regular glucose using b-glucosytransferase-catalyzed 5hmC glucosylation. Then, we selectively reduce 5fC with NaBH4 to 5hmC, and chemically label the resulting 5hmC (from 5fC) with an azide-modified glucose. Biotin can be installed subsequently for specific enrichment of 5fC. Our method thereby provides an effective tool of general utility for the genomic localization of 5fC. Here we provide genome-wide profiles of 5hmC, 5fC, and p300 in Tdg fl/fl and Tdg-/- mESCs as well as a 5fC control (Non-NaBH4) and polyA RNA-Seq expression data. Genome-wide profiles of 5hmC and 5fC in mESCs differentiated to embryoid bodies are also included. We also report the development and application of a single-base resolution method for the detection of 5fC in genomic DNA by hydroylamine mediated protection of 5fC from deamination during bisulfite treatment, or 5fC Chemical Assisted Bisulfite Sequencing (fCAB-Seq). We applied this method in parallel with conventional ChIP-Methyl-Seq to H3K4me1 ChIP enriched DNA from Tdg fl/fl and Tdg-/- mice.
2013-04-18 | E-GEOD-41545 | biostudies-arrayexpress
Project description:Background: Interindividual differences in liver functions such as protein synthesis, lipid and carbohydrate metabolism and drug metabolism are influenced by epigenetic factors. The role of the epigenetic machinery in such processes has, however, been barely investigated. 5-hydroxymethylcytosine (5hmC) is a recently re-discovered epigenetic DNA modification that plays an important role in the control of gene expression. Results: In this study, we investigate 5hmC occurrence and genomic distribution in 8 fetal and 7 adult human liver samples in relation to ontogeny and function. LC-MS analysis shows that in the adult liver samples 5hmc comprises up to 1% of the total cytosine content, whereas in all fetal livers it is below 0.125%. Immunohistostaining of liver sections with a polyclonal anti-5hmC antibody shows that 5hmC is detected in most of the hepatocytes. Genome-wide mapping of the distribution of 5hmC in human liver samples by next-generation sequencing shows significant differences between fetal and adult livers. In adult livers, 5hmC occupancy is overrepresented in genes involved in active catabolic and metabolic processes, whereas 5hmC elements which are found in genes exclusively in fetal livers and disappear in the adult state, are more specific to pathways for differentiation and development. Conclusions: Our findings suggest that 5-hydroxymethylcytosine plays an important role in the development and function of the human liver and might be an important determinant for development of liver diseases as well as of the interindividual differences in drug metabolism and toxicity. 8 fetal and 7 adult human liver samples
2013-07-29 | E-GEOD-49291 | biostudies-arrayexpress
Project description:Differentiation of CD4+T-cells into effector subsets is a critical component of the adaptive immune system and an incorrect response can lead to autoimmunity or immune deficiency. Cellular differentiation including T-cell differentiation is accompanied by large-scale epigenetic remodeling, including changes in DNA methylation at key regulators of T-cell differentiation. The TET family of enzymes were recently shown to be able to catalyse methylated cytosine (5mC) into 5-hydroxymethylcytosine (5hmC) enabling a pathway of active removal of DNA methylation. Here, we characterize 5hmC, 5mC and transcriptional dynamics during human CD4+T-cell polarisation in a time series approach and relate these changes to profiles in ex-vivo CD4+memory subsets. We observed large-scale remodelling during early CD4+T-cell differentiation which was predictive of subsequent changes during late time points, these changes were also related to disease associated regions which we show can act as functional regulatory elements. This dataset was designed to assess how 5-hydroxymethylcytosine (5hmC) changes over time during human CD4+T-cell polarization towards Th1 and Th2. We tested an early (1 day) and late (5 day) timepoint to distinguish between replication-independent (early) and replication-dependent (late) changes. When comparing the time-series profiles, we observed an early gain followed by a late loss of 5hmC suggesting active 5hmC remodelling precedes lineage specification in CD4+T-cells. This submission contains the data from genome-wide 5-hydroxymethylcytosine (5hmC) profiling by hMeDIP-seq in primary human CD4+T-cells polarized towards Th1 and Th2 time-series. This submission is part of series containing 5hmC and DNA methylation profiling of the same samples. See related experiments E-MTAB-4685, E-MTAB-4687, E-MTAB-4688, E-MTAB-4689.
2016-07-11 | E-MTAB-4686 | biostudies-arrayexpress
Project description:This SuperSeries is composed of the following subset Series: GSE32050: 5-hydroxymethylcytosine-mediated epigenetic dynamics during neurodevelopment and aging [5hmC Capture and Seq] GSE32187: 5-hydroxymethylcytosine-mediated epigenetic dynamics during neurodevelopment and aging [mRNA profiling] Refer to individual Series
2011-10-29 | E-GEOD-32188 | biostudies-arrayexpress
Project description:Mammalian somatic cells can be directly reprogrammed into induced pluripotent stem cells (iPSCs) by introducing defined sets of transcription factors. Somatic cell reprogramming involves epigenomic reconfiguration, conferring iPSCs with characteristics similar to embryonic stem (ES) cells. Human ES cells contain 5-hydroxymethylcytosine (5hmC), which is generated though the oxidation of 5-methylcytosine (5mC) by the TET family of enzymes. Here we show that 5hmC level increases significantly during reprogramming due to the activation of TET1. During this process, dynamic genome-wide 5hmC modification occurs across the genome with more modifications at telomere-proximal regions. Compared with hES cells, we found iPS cells tend to form large-scale (100kb-1.3Mb) aberrant reprogramming hotspots in subtelomeric regions, most of which display incomplete hydroxymethylation. Strikingly, these 5hmC aberrant hotspots largely coincide (>80%) with previously reported aberrant non-CG methylation regions. Our results suggest that 5hmC modification could play important roles during reprogramming to pluripotency, and contribute to the differences between iPSCs and hESCs. we generated comprehensive genome-wide profiles of 5hmC in somatic cells, iPS cell lines derived from a variety of origins, and multiple hES cell lines.
2013-03-21 | E-GEOD-37050 | biostudies-arrayexpress
Project description:Active DNA demethylation in mammals involves TET-mediated iterative oxidation of 5-methylcytosine (5mC)/5-hydroxymethylcytosine (5hmC) and subsequent excision repair of highly oxidized cytosine bases 5-formylcytosine (5fC)/5-carboxylcytosine (5caC) by Thymine DNA glycosylase (TDG). However, quantitative and high-resolution analysis of active DNA demethylation activity remains challenging. Here we describe M.SssI methylase-assisted bisulfite sequencing (MAB-seq), a method that directly maps 5fC/5caC at single-base resolution. Genome-wide MAB-seq allows systematic identification of 5fC/5caC in Tdg-depleted embryonic stem cells, thereby generating a base-resolution map of active DNA demethylome. A comparison of 5fC/5caC and 5hmC distribution maps indicates that catalytic processivity of TET enzymes correlates with local chromatin accessibility. MAB-seq also reveals strong strand asymmetry of active demethylation within palindromic CpGs. Integrating MAB-seq with other base-resolution mapping methods enables quantitative measurement of cytosine modification states at key transitioning steps of active demethylation pathway, and reveals a regulatory role of 5fC/5caC excision repair in active DNA demethylation cascade. Analysis of 5fC/5caC excision repair-dependent active DNA demethylome by MAB-seq in mouse embryonic stem cells.
2014-11-02 | E-GEOD-62631 | biostudies-arrayexpress
Project description:Investigations of 5-hydroxymethylcytosine (5hmC) in biologically and clinically samples and models with low cell numbers have been hampered by the low sensitivity and reproducibility using current 5hmC mapping approaches. Here, we develop a selective 5hmC chemical labeling approach using tagmentation-based library preparation in order to profile nanogram levels of 5hmC isolated from ~1,000 cells (nano-hmC-Seal). Using this technology, we profiled the dynamics of 5hmC across different stages of mouse hematopoietic differentiation. Additionally, applying nano-hmC-Seal to the hematopoietic multipotent progenitor cells in an acute myeloid leukemia (AML) mouse model, we identified leukemia-specific, differentially hydroxymethylated regions that harbor previously reported and as-yet-unidentified functionally relevant factors. The change of 5hmC patterns in AML strongly correlates with the altered gene expression on a global scale. Together, our new approach offers a highly sensitive and robust method to study and detect DNA methylation dynamics from in vivo model and clinical samples. Selective 5hmC chemical labeling approach using tagmentation-based library preparation in order to profile nanogram levels of 5hmC isolated from ~1,000 cells
2016-09-01 | E-GEOD-77967 | biostudies-arrayexpress
Project description:Gene-environment interactions mediated at the epigenetic level may provide an initial step in delivering an appropriate response to environmental changes. 5-hydroxymethylcytosine (5hmC), a DNA base derived from 5-methylcytosine (5mC), accounts for ~40% of modified cytosine in brain and has been implicated in DNA methylation-related plasticity. To identify the role of 5hmC in gene-environment interactions, we exposed both young (6-week-old) and aged (18-month-old) mice to both an enriched environment and a standard environment. Exposure to EE significantly improves learning and memory in aged mice and reduces 5hmC abundance in mouse hippocampus. Furthermore, we mapped the genome-wide distribution of 5hmC and found that the alteration of 5hmC modification occurred mainly at gene bodies. In particular, genes involved in axon guidance are enriched among the genes with altered 5hmC modification. These results together suggest that environmental enrichment could modulate the dynamics of 5hmC in hippocampus, which could potentially contribute to improved learning and memory in aged animals. To identify the role of 5hmC in gene-environment interactions, we exposed both young (6-week-old) and aged (18-month-old) C57B/6 mice to both an enriched environment (EE) and a standard environment. Exposure of mice to EE was achieved by keeping a group of mice in the EE chamber, which is larger than the standard cage, includes novel objects, such as toys of varied color and texture, tunnels, an exercise wheel for voluntary exercise, and extra bedding material, along with free access to food and water. Daily exposure to EE was kept at 5 hours during the daylight cycle for 4 consecutive weeks. Control animals were kept in their small cages that are used as standard housing cages (CE) containing bedding, food and access to water. YC, young mice exposing to control environment, YE, young mice exposing to enriched environment, AC, aged mice exposing to control environment, AE, aged mice exposed to enriched environment. Please note that 5hmC-containing DNA enrichment method was inspired by a unique character of beta-glucotransferase that can specifically add glucose to 5hmC modification. With a modified glucose conjugated with biotin, we are able to purify the 5hmC-containing DNA by biotin-streptavidin-based immunoprecipitation.
2014-09-11 | E-GEOD-61194 | biostudies-arrayexpress
Project description:Fragile X-associated tremor/ataxia syndrome (FXTAS) is a late-onset neurodegenerative disorder in which patients carry premutation alleles of 55-200 CGG repeats on the FMR1 gene. To date, whether alterations in epigenetic regulation modulate FXTAS has gone unexplored. 5-hydroxymethylcytosine (5hmC) converted from 5-methylcytosine (5mC) by the ten-eleven translocation (TET) family of proteins, has been found recently to play key roles in neuronal functions. Here we undertook genome-wide profiling of cerebellar 5hmC in a FXTAS mouse model (rCGG mice) and found that rCGG mice at 16 weeks showed overall reduced 5hmC levels genome-wide compared to age-matched wild-type littermates. However, we also observed gain-of-5hmC regions in repetitive elements, as well as cerebellum-specific enhancers, but not general enhancers. Genomic annotation and motif prediction of wild-type- and rCGG-specific differential 5-hydroxymethylated regions (DhMRs) revealed their high correlation with genes and transcription factors that are important in neuronal developmental and functional pathways. DhMR-associated genes partially overlapped with genes that were differentially associated with ribosomes in CGG mice identified by bacTRAP ribosomal profiling. Taken together, our data strongly indicate a functional role for 5hmC-mediated epigenetic modulation in the etiology of FXTAS, possibly through the regulation of transcription. Examination genome-wide 5hmC in FXTAS mice model
2013-10-17 | E-GEOD-49463 | biostudies-arrayexpress