Project description:DNA Methyltransferase 3A (DNMT3A) is frequently mutated in various hematopoietic malignancies; however, the underlying oncogenic mechanisms remain elusive. Here, we report that DNMT3A mutational âhotspotâ at Arg882 (DNMT3A-R882H) cooperates with constitutively activated RAS in transforming murine hematopoietic stem/progenitor cells (HSPCs) ex vivo and inducing acute leukemias in vivo. DNMT3A-R882H potentiates aberrant transactivation of âstemnessâ gene expression programs, notably transcription factors Meis1, Hox-A, Mn1 and Mycn. Mechanistically, R882-mutated DNMT3A directly binds to cis-regulatory elements of these genes and induces focal CpG hypomethylation reminiscent of what was seen in human leukemias bearing DNMT3A R882 mutation. Furthermore, DNMT3A-R882H induced DNA hypomethylation facilitates gene enhancer/promoter activation and recruitment of Dot1l-associated transcription elongation machineries. Inactivation of Dot1l represses DNMT3AR882H-mediated stem cell gene dysregulation and acute leukemogenicity. In this dataset, we provided enhanced Reduced Representation Bisulfite Sequencing (eRRBS) DNA methylome profiling data showing effect of DNMT3A R882H mutation or WT expression on hematopoietic stem/progenitor cells with NRAS G12D co-transduction. eRRBBs DNA methylome analysis of Lin- enriched hematopoietic stem/progenitor cells with retroviral infection of NRAS G12D alone (EV-RAS), DNMT3A R882H with NRAS G12D (RH-RAS) or DNMT3A WT with NRAS G12D (WT-RAS) at day 16 post-transduction.
Project description:DNA Methyltransferase 3A (DNMT3A) is frequently mutated in various hematopoietic malignancies; however, the underlying oncogenic mechanisms remain elusive. Here, we report that DNMT3A mutational âhotspotâ at Arg882 (DNMT3A-R882H) cooperates with constitutively activated RAS in transforming murine hematopoietic stem/progenitor cells (HSPCs) ex vivo and inducing acute leukemias in vivo. DNMT3A-R882H potentiates aberrant transactivation of âstemnessâ gene expression programs, notably transcription factors Meis1, Hox-A, Mn1 and Mycn. Mechanistically, R882-mutated DNMT3A directly binds to cis-regulatory elements of these genes and induces focal CpG hypomethylation reminiscent of what was seen in human leukemias bearing DNMT3A R882 mutation. Furthermore, DNMT3A-R882H induced DNA hypomethylation facilitates gene enhancer/promoter activation and recruitment of Dot1l-associated transcription elongation machineries. Inactivation of Dot1l represses DNMT3AR882H-mediated stem cell gene dysregulation and acute leukemogenicity. In this dataset, we provided H3K4me1, H3K27ac and H3K79me2 ChIP-seq profiling data showing effect of DNMT3A R882H mutation or WT expression on epigenetic landscapes of hematopoietic stem/progenitor cells with NRAS G12D co-transduction. ChIP-seq analysis of Lin- enriched hematopoietic stem/progenitor cells with retroviral infection of NRAS G12D alone (EV-RAS), DNMT3A R882H with NRAS G12D (RH-RAS) or DNMT3A WT with NRAS G12D (WT-RAS) 3 weeks post-transduction. Antibodies of H3K4me1, H3K27ac and H3K79me2 were used.
Project description:DNA Methyltransferase 3A (DNMT3A) is frequently mutated in various hematopoietic malignancies; however, the underlying oncogenic mechanisms remain elusive. Here, we report that DNMT3A mutational âhotspotâ at Arg882 (DNMT3A-R882H) cooperates with constitutively activated RAS in transforming murine hematopoietic stem/progenitor cells (HSPCs) ex vivo and inducing acute leukemias in vivo. DNMT3A-R882H potentiates aberrant transactivation of âstemnessâ gene expression programs, notably transcription factors Meis1, Hox-A, Mn1 and Mycn. Mechanistically, R882-mutated DNMT3A directly binds to cis-regulatory elements of these genes and induces focal CpG hypomethylation reminiscent of what was seen in human leukemias bearing DNMT3A R882 mutation. Furthermore, DNMT3A-R882H induced DNA hypomethylation facilitates gene enhancer/promoter activation and recruitment of Dot1l-associated transcription elongation machineries. Inactivation of Dot1l represses DNMT3AR882H-mediated stem cell gene dysregulation and acute leukemogenicity. In this dataset, we provided R882H-mutated DNMT3A, H3K4me1, H3K4me3 and H3K27me3 ChIP-seq profiling data of RH-RAS LSCs, and H3K4me1 ChIP-seq data in HOXA9-MEIS1 LSCs. Genome-wide binding of R882H-mutated DNMT3A (Myc tagged; ChIP-seq with 9e10 anti-Myc antibodies) and histone modification profiles for H3K4me1, H3K4me3 and H3K27me3 were generated by ChIP-seq using specific antibodies in RH-RAS LSCs. Genome-wide H3K4me1 histone modification profiles were generated by ChIP-seq using H3K4me1 specific antibody in HOXA9-MEIS1 LSCs.
Project description:DNMT3a is a de novo DNA methyltransferase expressed robustly after T cell activation that regulates plasticity of CD4+ T cell cytokine expression. Here we show that DNMT3a is critical for directing early CD8+ T cell effector and memory fate decisions. While effector function of DNMT3a knockout T cells is normal, they develop more memory precursor and fewer terminal effector cells in a T cell intrinsic manner compared to wild-type animals. Rather than increasing plasticity of differentiated effector CD8+ T cells, loss of DNMT3a biases differentiation of early effector cells into memory precursor cells. This is attributed in part to ineffective repression of Tcf1 expression in knockout T cells, as DNMT3a localizes to the Tcf7 promoter and catalyzes its de novo methylation in early effector WT CD8+ T cells. This data identifies DNMT3a as a crucial regulator of CD8+ early effector cell differentiation and effector versus memory fate decisions. Examination of global genomic DNA methylation by MBD-seq in naïve CD8 T cells and CD8 T cells 8 days post Vaccinia-Ova infection, comparing OT1 TCR-Tg CD8 T cells isolated from WT and T cell conditional DNMT3a KO mice.
Project description:To examine whether Dnmt3a deficiency resulted in genomic methylation changes we performed an unbiased methylome analysis. Methylated DNA isolated from three Dnmt3a deficient and two WT tumors was immunoprecipitated and subjected to high throughput sequencing (MeDIP-Seq). We observed that genes that were less expressed in Dnmt3a deficient tumors tended to have lower methylation levels in gene bodies. Examination of methylcytosine in two tumor types
Project description:The results of the study uncover conserved features of cancer methylomes and provide a mechanistic explanation for the tumor-promoting effects of Dnmt3a mutations. Whole genome methylation analysis of Mus musculus. Five samples were analyzed, one control sample containing normal healthy lung tissue, two samples containing big (WTB) or small (WTS) Dnmt3a WT tumors, two samples containing big (KOB) or small (KOS) Dnmt3a knock-out tumors
Project description:We investigate the dynamics for Histone marks H3K4me3 and H3K27me3 during Dnmt3a and Dnmt3b knockout in mouse hematopoietic stem cells. The term dko represents double knockout of both Dnmt3a and Dnmt3b, while the term sko denotes single knockout of Dnmt3a. The Wildtype profiles were generated in study GSE47765. Mouse hematopoietic stem cell histone methylation profiles of sko and dko mice were generated generated by deep sequencing, in duplicate, using Illumina Hiseq 2000
Project description:Gains and losses in DNA methylation are prominent genomic features of all mammalian cell types. To gain insight into mechanisms that could promote shifts in DNA methylation patterns and thus contribute to cell fate, including malignant transformation, we performed genome-wide mapping of 5-methylcytosine in purified wild type and Dnmt3a conditional knockout hematopoietic stem cells (HSCs). We generated 1,121 million (control HSCs), and 1,213 million (Dnmt3a knockout HSCs) raw reads; about 81.4% and 88.7%, respectively, were successfully aligned to either strand of the reference genome (mm9), obtainig an average CG coverage of 39.5-fold (wild type) and 47.0-fold (Dnmt3a kockout). Whole genome bisulfite sequencing of secondarily-transplanted wild-type and Dnmt3a conditional knockout hematopoietic stem cells using Illumina HiSeq 2000
Project description:Cytosine methylation is an epigenetic mark usually associated with gene repression. Despite a requirement for de novo DNA methylation for differentiation of embryonic stem cells, its role in somatic stem cells is unknown. Using conditional ablation, we show that loss of either, or both, Dnmt3a or Dnmt3b, progressively impedes hematopoietic stem cell (HSC) differentiation during serial in vivo passage. Concomitantly, HSC self-renewal is immensely augmented in absence of either Dnmt3, particularly Dnmt3a. Dnmt3-KO HSCs show upregulation of HSC multipotency genes and downregulation of early differentiation factors, and the differentiated progeny of Dnmt3-KO HSCs exhibit hypomethylation and incomplete repression of HSC-specific genes. HSCs lacking Dnmt3a manifest hyper-methylation of CpG islands and hypo-methylation of genes which are highly correlated with human hematologic malignancies. These data establish that aberrant DNA methylation has direct pathologic consequences for somatic stem cell development, leading to inefficient differentiation and maintenance of a self-renewal program. Reduced representation bisulfite sequencing (MspI,~40-220bp size fraction) of secondarily-transplanted wild-type and Dnmt3a conditional knockout hematopoietic stem cells. We used microarrays to detail the global expression of genes in secondarily-transplanted control-HSCs and Dnmt3a-KO-HSCs.
Project description:To investigate the global DNA methylation changes in Dnmt3a-KO and Dnmt3ab-dKO HSCs compared to control HSCs, we performed whole genome bisulfite sequencing Mouse hematopoietic stem cell DNA methylation profiles of control, Dnmt3a-KO and Dnmt3ab-dKO HSCs were generated generated by deep sequencing, in duplicate, using Illumina Hiseq 2000