Global distribution of DNA hydroxymethylation and DNA methylation in chronic lymphocytic leukemia
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE113386 | GEO | 2019/01/23
REPOSITORIES: GEO
Similar Datasets
Project description:Methylation at the 5-position of cytosine is a well-studied epigenetic pathway. In addition to 5-methylcytosine (5mC), substantial amounts of 5-hydroxymethylcytosine (5hmC) also referred to as the 6th DNA base, have been detected in certain tissues, most notably the brain. However, the genomic distribution of this cytosine modification is unknown. Here, we have developed an immunoprecipitation technique (5hmC-IP) to examine the occurrence of 5hmC in human DNA from brain frontal lobe tissue. The distribution of 5hmC was compared to that of 5mC. We show that 5hmC is more selectively targeted to genes than is 5mC. 5hmC is found at promoters and is particularly enriched in intragenic regions (gene bodies) but is largely absent from non-gene regions. 5hmC peaks at transcription start sites did not correlate with gene expression levels or H3K4me3 peaks. However, presence of 5hmC in gene bodies was more positively correlated with gene expression levels than was presence of 5mC. Promoters of testis-specific genes showed strong 5mC peaks in brain DNA but were almost completely devoid of 5hmC. Our data provide a first overview of the genomic distribution of 5hmC in human brain and will set the stage for further functional characterization of this novel DNA modification. Comparison between 5hmC and 5mC profiles
2011-03-01 | E-GEOD-27051 | biostudies-arrayexpress
Project description:Methylation at the 5-position of cytosine is a well-studied epigenetic pathway. In addition to 5-methylcytosine (5mC), substantial amounts of 5-hydroxymethylcytosine (5hmC) also referred to as the 6th DNA base, have been detected in certain tissues, most notably the brain. However, the genomic distribution of this cytosine modification is unknown. Here, we have developed an immunoprecipitation technique (5hmC-IP) to examine the occurrence of 5hmC in human DNA from brain frontal lobe tissue. The distribution of 5hmC was compared to that of 5mC. We show that 5hmC is more selectively targeted to genes than is 5mC. 5hmC is found at promoters and is particularly enriched in intragenic regions (gene bodies) but is largely absent from non-gene regions. 5hmC peaks at transcription start sites did not correlate with gene expression levels or H3K4me3 peaks. However, presence of 5hmC in gene bodies was more positively correlated with gene expression levels than was presence of 5mC. Promoters of testis-specific genes showed strong 5mC peaks in brain DNA but were almost completely devoid of 5hmC. Our data provide a first overview of the genomic distribution of 5hmC in human brain and will set the stage for further functional characterization of this novel DNA modification.
2011-03-01 | GSE27051 | GEO
Project description:Genomic imprinting is a important biological process, which leads to parental specific gene expressions. Improper gene imprinting results in several developmental abnormalities, cancer and other diseases. Studies in mice indicated genomic imprinting establishment relied on parental allele-specific DNA methylation during gametogenesis. Despite the fact that genomic imprinting is highly conserved in mammalian, the species specific pattern exists. Until now, except that of in mouse, informations about imprinting patterns is little, especially in primates. Through generation genome-wide 5mC and 5hmC profiles for two types of haploid genomes from rhesus monkeys, including parthenogenetic haploid ESCs ( PG ha ESCs) (derived from rhesus monkey parthenogenetic embryos) and sperms. We clearly characterized and distinguished methylome (5mC) from hydroxymethylome (5hmC)(which can not discriminate from methylome in traditional bisulfite (BS) sequencing) in haploid genomes. Based on these information, we determined distribution patterns of 5mC and 5hmC in ha ESCs and sperms. Interestingly, both 5hmC levels and distribution patterns were similar in ha ESCs and sperms, and 5hmC which is enriched in the regions with low 5mC frequency. Meanwhile through comparing DNA methylation and hydroxymethylation status between sperms and ha ESCs, we first provided a fundamental information of monkey imprinted differentially methylated regions (DMRs) distribution in monkey chromosomes. Second, we observed that DMRs did not overlap with hydroxymethylated regions (DMR or DhMR), suggesting that establishment of imprinted regions was not interfered by 5hmC. Our results demonstrate DNA methylation profiling of PG ha ESCs and sperms can be uesed as a powerful and effective method to map and characterize imprinted regions in non-human primates genome.
2016-12-08 | GSE75817 | GEO
Project description:DNA methylation at the 5-position of cytosine (5-mC) is a key epigenetic mark critical for varius biological and pathological processes. 5-mC can be converted to 5-hydroxymethylcytosine (5-hmC) by the Ten-Eleven Translocation (TET) family of DNA hydroxylases. Here we report that "loss of 5-hmC" is an epigenetic hallmark of melanoma with diagonostic and prognostic implications. Genome-wide mapping of 5-hmC in nevi and melanomas for the first time revealed loss of 5-hmC landscape in the melanoma epigenome. Downregulation of Isocitrate Dehydrogenase 2 (IDH2) and TET family enzymes proved to be one of the mechanisms underlying the loss of 5-hmC during melanoma development, and rebuilding the 5-hmC landscape in the melanoma epigenome by reintroducing active TET2 or IDH2 suppressed melanoma growth and increased tumor-free survival. Thus, our study establishes that "loss of 5-hmC" is a new epigenetic hallmark of melanoma and links IDH and TET family enzymes-mediated 5-hmC putative tumor suppressor pathway to the suppression of melanoma progression. Determine the genome-wide distribution of 5mC and 5hmC in benign nevus tissue, melanoma tissue, A2058 MOCK cells (overexpressing empty vector), A2058 TET2 cells (overexpressing wild type human TET), and A2058 TET2M cells (overexpressing mutant human TET).
2012-09-18 | E-GEOD-38231 | biostudies-arrayexpress
Project description:Identification the genome-wide distribution of 5-hmC in WT-MSCs and Tet2-/--MSCs by Genome-wide 5hmc Profiling.
2018-02-13 | GSE100072 | GEO
Project description:Adipose tissue is important for systemic metabolic homeostasis in response to environmental changes, and adipogenesis involves dynamic transcriptional regulation. DNA methylation on cytosine (C) of CpG (5mC) is an abundant epigenetic modification that mediates genomic imprinting and regulates gene expression. TET family enzymes (TET1, TET2 and TET3) oxidize the 5mC in DNA to 5-hydroxylmethylcytosine (5hmC), which associates with transcriptional activation. Through a phenotypic screen, we found TET inhibition decreased adipocyte differentiation from mesenchymal stem cells (MSCs). Comparing with the undifferentiated MSCs, the differentiated adipocytes exhibited much higher levels of 5hmC and slightly increased 5fC and 5caC. Higher 5hmC associated with better differentiation at single cell level. TET1 is upregulated in differentiation and depletion of it significantly impaired the gain of 5hmC. Furthermore, Tet1 depletion significantly hampered the adipocyte differentiation in vitro and adipose tissue maintenance in vivo. Using RNA-seq, 5mC and 5hmC-DNA immunoprecipitation, we found that Tet1 knockout led to decreased expression of genes associated with lipid metabolism and fat cell differentiation. Genes with loss of 5mC or gain of 5hmC in adipocytes include Lipe, Bmp4 and Rxra etc. Rxra is one of the critical TET1 modulated genes for adipose development, as RXRα agonist partially rescued the inhibitory effect of Tet1 knockout. Together, TET1-mediated active DNA demethylation plays an important role in adipose tissue.
2021-06-30 | GSE144644 | GEO
Project description:Adipose tissue is important for systemic metabolic homeostasis in response to environmental changes, and adipogenesis involves dynamic transcriptional regulation. DNA methylation on cytosine (C) of CpG (5mC) is an abundant epigenetic modification that mediates genomic imprinting and regulates gene expression. TET family enzymes (TET1, TET2 and TET3) oxidize the 5mC in DNA to 5-hydroxylmethylcytosine (5hmC), which associates with transcriptional activation. Through a phenotypic screen, we found TET inhibition decreased adipocyte differentiation from mesenchymal stem cells (MSCs). Comparing with the undifferentiated MSCs, the differentiated adipocytes exhibited much higher levels of 5hmC and slightly increased 5fC and 5caC. Higher 5hmC associated with better differentiation at single cell level. TET1 is upregulated in differentiation and depletion of it significantly impaired the gain of 5hmC. Furthermore, Tet1 depletion significantly hampered the adipocyte differentiation in vitro and adipose tissue maintenance in vivo. Using RNA-seq, 5mC and 5hmC-DNA immunoprecipitation, we found that Tet1 knockout led to decreased expression of genes associated with lipid metabolism and fat cell differentiation. Genes with loss of 5mC or gain of 5hmC in adipocytes include Lipe, Bmp4 and Rxra etc. Rxra is one of the critical TET1 modulated genes for adipose development, as RXRα agonist partially rescued the inhibitory effect of Tet1 knockout. Together, TET1-mediated active DNA demethylation plays an important role in adipose tissue.
2021-06-30 | GSE144613 | GEO
Project description:Through parallel processing of genomic DNA with bisulfite and oxidative bisulfite treatments on Illumina 450K arrays we resolved both 5mC and 5hmC in glioblastoma tissues. We developed and applied a novel technique for estimating 5mC, 5hmC, and unmethylated proportions from array data to glioblastoma tissues and compare with normal brain tissue. Genomic distribution of 5hmC was associated with features of transcription despite the glioblastoma genome being relatively depleted of 5hmC. When integrating 5mC and 5hmC data using a Gaussian finite mixture model approach, we observed significant associations between 5hmC levels and gene-sets involved in immune and RNA regulatory processes. We also observed an enrichment of 5hmC in introns, enhancer regions, and genes that are actively transcribed in glioblastomas from TCGA. Significant differences in patient survival were observed among classes of 5hmC obtained from a recursively partitioned mixture model.
2016-08-22 | GSE73895 | GEO
Project description:Through parallel processing of genomic DNA with bisulfite and oxidative bisulfite treatments on Illumina 450K arrays we resolved both 5mC and 5hmC in glioblastoma tissues. We developed and applied a novel technique for estimating 5mC, 5hmC, and unmethylated proportions from array data to glioblastoma tissues and compare with normal brain tissue. Genomic distribution of 5hmC was associated with features of transcription despite the glioblastoma genome being relatively depleted of 5hmC. When integrating 5mC and 5hmC data using a Gaussian finite mixture model approach, we observed significant associations between 5hmC levels and gene-sets involved in immune and RNA regulatory processes. We also observed an enrichment of 5hmC in introns, enhancer regions, and genes that are actively transcribed in glioblastomas from TCGA. Significant differences in patient survival were observed among classes of 5hmC obtained from a recursively partitioned mixture model. Glioblastoma dervied (n=30) DNA was subjected to tandem bisulfite and oxidative bisulfite conversion with an input of 4ug per sample using the TrueMethyl® kit v.1.1 (Cambridge Epigenetix) protocol optimized for Illumina HumanMethylation450 arrays.
2016-08-22 | E-GEOD-73895 | biostudies-arrayexpress
Project description:Cytosine DNA bases can be methylated by DNA methyltransferases and subsequently oxidized by TET proteins. The resulting 5-hydroxymethylcytosine (5hmC), 5-formylcytosine (5fC), and 5-carboxylcytosine (5caC) are considered demethylation intermediates as well as stable epigenetic marks. To dissect the contribution of these cytosine modifying enzymes, we generated combinations of Tet knockout (KO) embryonic stem cells (ESCs) and systematically measured protein and DNA modification levels at the transition from naive to primed pluripotency. Whereas the increase of genomic 5-methylcytosine (5mC) levels during exit from pluripotency correlated with an upregulation of the de novo DNA methyltransferases DNMT3A and DNMT3B, the subsequent oxidation steps turned out to be far more complex. The strong increase of oxidized cytosine bases (5hmC, 5fC, and 5caC) was accompanied by a drop in TET2 levels, yet the analysis of KO cells suggested that TET2 is responsible for most 5fC formation. The comparison of modified cytosine and enzyme levels in Tet KO cells revealed distinct and differentiation-dependent contributions of TET1 and TET2 to 5hmC and 5fC formation arguing against a processive mechanism of 5mC oxidation. The apparent independent steps of 5hmC and 5fC formation suggest yet to be identified mechanisms regulating TET activity and may constitute another layer of epigenetic regulation.
2020-07-24 | PXD019514 | Pride