Project description:Genome wide DNA methylation profiling of somatic and pluripotent cells from different lineages (mesoderm, endoderm and parthenogenetic germ cells) The Illumina Infinium 27k Human DNA methylation Beadchip v1.2 was used to obtain DNA methylation profiles across approximately 27,000 CpGs. Samples included 1 Human ES cell line, 2 beta cells, 2 beta-iPS cells, 1 fibroblast, 2 fibroblast-iPS cells, 2 parthenogenetic cells and 3 parthenogenetic-iPS cells. Molecular reprogramming of somatic cells into human induced pluripotent stem cells (iPSCs) is accompanied by extensive changes in gene expression patterns and epigenetic marks. To better understand the link between gene expression and DNA methylation, we have profiled human somatic cells from different embryonic cell types (endoderm, mesoderm and parthenogenetic germ cells) and the iPSCs generated from them. We show that reprogramming is accompanied by extensive DNA methylation in CpG-poor promoters, sparing CpG-rich promoters. Intriguingly, methylation in CpG-poor promoters occurred not only in downregulated genes, but also in genes that are not expressed in the parental somatic cells or their respective iPSCs. These genes are predominantly tissue-specific genes of other cell types from different lineages. Our results suggest a role of DNA methylation in the silencing of the somatic cell identity by global non-specific methylation of tissue-specific genes from all lineages, regardless of their expression in the parental somatic cells. Genomic DNA from each sample was bisulfite converted, DNA was applied to BeadChips (Illumina). 13 samples included, Human ES cell as control.
Project description:We apply cellular reprogramming to an induced pluripotent cell state to human cell lines and primary samples exhibiting Chronic Myoloid Leukemia (CML). Addtionally, we generated an inducible CML BCR-ABL transgenic mouse model. Biological replicates (duplicates) were available for all samples. DNA methylation profiles for all cells were generated using Reduced Representation Bisulfite Sequencing (RRBS). DNA methylation profiling of human leukemia cell lines, primary cells, derived iPS cells as well as transgenic mouse models for CML in duplicates using RRBS.
Project description:Genome wide DNA methylation profiling of somatic and pluripotent cells from different lineages (mesoderm, endoderm and parthenogenetic germ cells) The Illumina Infinium 27k Human DNA methylation Beadchip v1.2 was used to obtain DNA methylation profiles across approximately 27,000 CpGs. Samples included 1 Human ES cell line, 2 beta cells, 2 beta-iPS cells, 1 fibroblast, 2 fibroblast-iPS cells, 2 parthenogenetic cells and 3 parthenogenetic-iPS cells. Molecular reprogramming of somatic cells into human induced pluripotent stem cells (iPSCs) is accompanied by extensive changes in gene expression patterns and epigenetic marks. To better understand the link between gene expression and DNA methylation, we have profiled human somatic cells from different embryonic cell types (endoderm, mesoderm and parthenogenetic germ cells) and the iPSCs generated from them. We show that reprogramming is accompanied by extensive DNA methylation in CpG-poor promoters, sparing CpG-rich promoters. Intriguingly, methylation in CpG-poor promoters occurred not only in downregulated genes, but also in genes that are not expressed in the parental somatic cells or their respective iPSCs. These genes are predominantly tissue-specific genes of other cell types from different lineages. Our results suggest a role of DNA methylation in the silencing of the somatic cell identity by global non-specific methylation of tissue-specific genes from all lineages, regardless of their expression in the parental somatic cells.
Project description:DNA methylation patterns are established in early embryogenesis and are critical for cellular differentiation. To investigate the role of CG methylation in potential enhancer formation, we assessed H3K4me1 modification in murine embryonic fibroblasts (MEFs) derived from the DNA methylation mutant Lsh(-/-) mice. We report here de novo formation of putative enhancer elements at CG hypomethylated sites that can be dynamically altered. We found a subset of differentially enriched H3K4me1 regions clustered at neuronal lineage genes and overlapping with known cis-regulatory elements present in brain tissue. Reprogramming of Lsh(-/-) MEFs into induced pluripotent stem (iPS) cells leads to increased neuronal lineage gene expression of premarked genes and enhanced differentiation potential of Lsh(-/-) iPS cells toward the neuronal lineage pathway compared with WT iPS cells in vitro and in vivo. The state of CG hypomethylation and H3K4me1 enrichment is partially maintained in Lsh(-/-) iPS cells. The acquisition of H3K27ac and activity of subcloned fragments in an enhancer reporter assay indicate functional activity of several of de novo H3K4me1-marked sequences. Our results suggest a functional link of H3K4me1 enrichment at CG hypomethylated sites, enhancer formation, and cellular plasticity.