OSKM factors cooperatively engage chromatin to initiate reprogramming
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE36570 | GEO | 2012/11/16
SECONDARY ACCESSION(S): PRJNA153727
REPOSITORIES: GEO
Similar Datasets
Project description:Reprogramming cells from one fate to another, using transcription factors, generates cells for research and potential therapy, yet little is known about the initial engagement of reprogramming factors with the genome. We mapped the interactions between Oct4, Sox2, Klf4, and c-Myc (OSKM) and the human genome during the first 48 hours of cellular reprogramming to pluripotency. Unlike that reported in ES/iPS cells, we find extensive overlap in the initial binding of OSKM, demonstrating that the initial regulatory network differs markedly from that in pluripotency. OSK act as pioneer factors for c-Myc, and c-Myc enhances the engagement of OSK, including at many genes that are required for conversion to pluripotency. Distal enhancer sites in closed chromatin dominate the initial OSKM distribution. Hierarchical chromatin binding during reprogramming resembles that employed during development. Four chIP-seq data sets (Oct4, Sox2, Klf4, and c-Myc) are included, one lane per factor, no replicates. Also included is an input lane from the same conditions and two mock lentiviral controls (no exogenous OSKM factors) treated with Oct4 IP and c-Myc IP.
2012-11-16 | E-GEOD-36570 | biostudies-arrayexpress
Project description:Forced expression of four transcription factors Oct4,Sox2, Klf4 and Myc (OSKM) induces somatic cell reprogramming towards pluripotency. Major efforts have been made to characterize the molecular events involved in this process. Yet, it remains elusive how gene expression change, epigenetic landscape remodelling and cell fate conversion are triggered by expression of these Yamanaka factors.To address this gap,we utilized a secondary inducible reprogramming system and performed genome-wide profilings of Oct4 binding, histone modification(H3K4me3/H3K27me3/H3K4me1/H3K27ac), and gene expression analysis during this process. Through integrative analysis, we revealed stage-specific Oct4 binding and enhancer signatures in consistence with gene expression changes,in which the initial regression of somatic program is followed by the gradual acquisition of pluripotent program. Oct4 preferatially binds to H3K4me1 marked enhancer regions and Oct4 binding is positively correlated with active mark H3K27ac. Moreover,we observed significant enhancer activation of epigenetic related genes, especially acetylation associated genes, prior to pluripotency network activation, suggesting a pivotal role of epigenetic remodelling in the process of pluripotency acquisition and maintenance. We used ChIP-seq to explore the global changes of Oct4 binding profiling during OSKM-mediated somatic cell reprogramming. The exogenous Oct4 was tagged with 3XFlag, thus we used anti-flag antibody to monitor exogenous Oct4 changes; anti-Oct4 antibody which recognizes both endogenous and exogenous Oct4 was used to monitor total Oct4 changes during iPSC induction. In addition, we also examined genome-wide H3K4me1/H3K27ac/H3K4me3/H3K27me3/RNAPII profiling during 3Flag-OSKM 2' reprogramming.
2015-12-31 | E-GEOD-67520 | biostudies-arrayexpress
Project description:While the reprogramming factors OCT4, SOX2, KLF4, and MYC (OSKM) can reactivate the pluripotency network in terminally differentiated cells, they also regulate expression of non-pluripotency genes in other contexts, such as the mouse primitive endoderm. The primitive endoderm is an extraembryonic lineage established alongside the pluripotent epiblast in the blastocyst, and is the progenitor pool for extraembryonic endoderm stem (XEN) cells. Several studies have shown that endodermal genes are upregulated in fibroblasts undergoing reprogramming, although whether endodermal genes promote or inhibit acquisition of pluripotency is unclear. We show that, in fibroblasts undergoing conventional reprogramming, OSKM-induced expression of endodermal genes leads to formation of induced XEN (iXEN) cells, which possess key properties of blastocyst-derived XEN cells, including morphology, transcription profile, self-renewal, and multipotency. Our data show that iXEN cells arise in parallel to iPS cells, indicating that OSKM are sufficient to drive cells to two distinct fates during reprogramming. Sequence-based mRNA transcriptional profiling of three different cell lines (MEF, XEN, iXEN) with multiple biological replicates, under two different growth medium conditions (ESC medium, XEN medium) for XEN and iXEN cells.
2016-03-03 | E-GEOD-77550 | biostudies-arrayexpress
Project description:Oct4, Sox2, Klf4, and cMyc (OSKM) reprogram somatic cells to pluripotency. To gain a mechanistic understanding of their function, we mapped OSKM-binding, stage-specific transcription-factors (TFs), and chromatin-states in discrete reprogramming stages and performed loss- and gain-of-function experiments. We found that early in reprogramming OSK extensively bind somatic-enhancers and initiate their decommissioning by recruiting Hdac1. Concurrently, OSK engage other sites, including specific pluripotency-enhancers, and induce the relocation of somatic TFs to these sites and away from somatic-enhancers, extending somatic-enhancer decommissioning genome-wide. Pluripotency-enhancer selection early in reprogramming occurs predominantly at sites with high OSK-motif densities and requires collaborative binding by OSK. Most pluripotency-enhancers are selected later and occupied by OS and stage-specific-TFs like Esrrb. Overexpression of stage-specific-TFs influences reprogramming efficiency by changing OSK-occupancy, somatic-enhancer decommissioning, and pluripotency-enhancer selection. We propose that collaborative interactions among OSK and with stage-specific-TFs direct both somatic-enhancer decommissioning and pluripotency-enhancer selection, which drives the enhancer reorganization underlying reprogramming
2017-01-19 | GSE90894 | GEO
Project description:Oct4, Sox2, Klf4, and cMyc (OSKM) reprogram somatic cells to pluripotency. To gain a mechanistic understanding of their function, we mapped OSKM-binding, stage-specific transcription-factors (TFs), and chromatin-states in discrete reprogramming stages and performed loss- and gain-of-function experiments. We found that early in reprogramming OSK extensively bind somatic-enhancers and initiate their decommissioning by recruiting Hdac1. Concurrently, OSK engage other sites, including specific pluripotency-enhancers, and induce the relocation of somatic TFs to these sites and away from somatic-enhancers, extending somatic-enhancer decommissioning genome-wide. Pluripotency-enhancer selection early in reprogramming occurs predominantly at sites with high OSK-motif densities and requires collaborative binding by OSK. Most pluripotency-enhancers are selected later and occupied by OS and stage-specific-TFs like Esrrb. Overexpression of stage-specific-TFs influences reprogramming efficiency by changing OSK-occupancy, somatic-enhancer decommissioning, and pluripotency-enhancer selection. We propose that collaborative interactions among OSK and with stage-specific-TFs direct both somatic-enhancer decommissioning and pluripotency-enhancer selection, which drives the enhancer reorganization underlying reprogramming
2017-01-19 | GSE90893 | GEO
Project description:Oct4, Sox2, Klf4, and cMyc (OSKM) reprogram somatic cells to pluripotency. To gain a mechanistic understanding of their function, we mapped OSKM-binding, stage-specific transcription-factors (TFs), and chromatin-states in discrete reprogramming stages and performed loss- and gain-of-function experiments. We found that early in reprogramming OSK extensively bind somatic-enhancers and initiate their decommissioning by recruiting Hdac1. Concurrently, OSK engage other sites, including specific pluripotency-enhancers, and induce the relocation of somatic TFs to these sites and away from somatic-enhancers, extending somatic-enhancer decommissioning genome-wide. Pluripotency-enhancer selection early in reprogramming occurs predominantly at sites with high OSK-motif densities and requires collaborative binding by OSK. Most pluripotency-enhancers are selected later and occupied by OS and stage-specific-TFs like Esrrb. Overexpression of stage-specific-TFs influences reprogramming efficiency by changing OSK-occupancy, somatic-enhancer decommissioning, and pluripotency-enhancer selection. We propose that collaborative interactions among OSK and with stage-specific-TFs direct both somatic-enhancer decommissioning and pluripotency-enhancer selection, which drives the enhancer reorganization underlying reprogramming
2017-01-19 | GSE90892 | GEO
Project description:While the reprogramming factors OCT4, SOX2, KLF4, and MYC (OSKM) can reactivate the pluripotency network in terminally differentiated cells, they also regulate expression of non-pluripotency genes in other contexts, such as the mouse primitive endoderm. The primitive endoderm is an extraembryonic lineage established alongside the pluripotent epiblast in the blastocyst, and is the progenitor pool for extraembryonic endoderm stem (XEN) cells. Several studies have shown that endodermal genes are upregulated in fibroblasts undergoing reprogramming, although whether endodermal genes promote or inhibit acquisition of pluripotency is unclear. We show that, in fibroblasts undergoing conventional reprogramming, OSKM-induced expression of endodermal genes leads to formation of induced XEN (iXEN) cells, which possess key properties of blastocyst-derived XEN cells, including morphology, transcription profile, self-renewal, and multipotency. Our data show that iXEN cells arise in parallel to iPS cells, indicating that OSKM are sufficient to drive cells to two distinct fates during reprogramming.
2016-03-03 | GSE77550 | GEO
Project description:Forced expression of four transcription factors Oct4,Sox2, Klf4 and Myc (OSKM) induces somatic cell reprogramming towards pluripotency. Major efforts have been made to characterize the molecular events involved in this process. Yet, it remains elusive how gene expression change, epigenetic landscape remodelling and cell fate conversion are triggered by expression of these Yamanaka factors. To address this gap, we utilized a secondary inducible reprogramming system and performed genome-wide profilings of Oct4 binding, histone modification (H3K4me3/H3K27me3/H3K4me1/H3K27ac), and gene expression analysis during this process. Through integrative analysis, we revealed stage-specific Oct4 binding and enhancer signatures in consistence with gene expression changes, in which the initial regression of somatic program is followed by the gradual acquisition of pluripotent program. Oct4 preferatially binds to H3K4me1 marked enhancer regions and Oct4 binding is positively correlated with active mark H3K27ac. Moreover, we observed significant enhancer activation of epigenetic related genes, especially acetylation associated genes, prior to pluripotency network activation, suggesting a pivotal role of epigenetic remodelling in the process of pluripotency acquisition and maintenance. We used microarrays to explore the global changes of gene expression during OSKM-mediated somatic cell reprogramming.
2015-12-31 | GSE67462 | GEO
Project description:Forced expression of four transcription factors Oct4,Sox2, Klf4 and Myc (OSKM) induces somatic cell reprogramming towards pluripotency. Major efforts have been made to characterize the molecular events involved in this process. Yet, it remains elusive how gene expression change, epigenetic landscape remodelling and cell fate conversion are triggered by expression of these Yamanaka factors.To address this gap,we utilized a secondary inducible reprogramming system and performed genome-wide profilings of Oct4 binding, histone modification(H3K4me3/H3K27me3/H3K4me1/H3K27ac), and gene expression analysis during this process. Through integrative analysis, we revealed stage-specific Oct4 binding and enhancer signatures in consistence with gene expression changes,in which the initial regression of somatic program is followed by the gradual acquisition of pluripotent program. Oct4 preferatially binds to H3K4me1 marked enhancer regions and Oct4 binding is positively correlated with active mark H3K27ac. Moreover,we observed significant enhancer activation of epigenetic related genes, especially acetylation associated genes, prior to pluripotency network activation, suggesting a pivotal role of epigenetic remodelling in the process of pluripotency acquisition and maintenance. We used microarrays to explore the global changes of gene expression during OSKM-mediated somatic cell reprogramming. time series design with bulk population samples collected at different time point of 2nd reprogramming as well as a corresponding iPS cell line. Each sample include two replicates. 2nd mouse embryonic fibroblasts(sample day0) were treated with ES medium supplemented with 1µg/ml Doxcycline and 50µg/ml Vitamin C for 15 days (sample day1-day15); 72 hours after dox and Vc withdrawl, dox-independent iPS cells are collected(sample day18).
2015-12-31 | E-GEOD-67462 | biostudies-arrayexpress
Project description:Forced expression of four transcription factors Oct4,Sox2, Klf4 and Myc (OSKM) induces somatic cell reprogramming towards pluripotency. Major efforts have been made to characterize the molecular events involved in this process. Yet, it remains elusive how gene expression change, epigenetic landscape remodelling and cell fate conversion are triggered by expression of these Yamanaka factors. To address this gap,we utilized a secondary inducible reprogramming system and performed genome-wide profilings of Oct4 binding, histone modification (H3K4me3/H3K27me3/H3K4me1/H3K27ac), and gene expression analysis during this process. Through integrative analysis, we revealed stage-specific Oct4 binding and enhancer signatures in consistence with gene expression changes, in which the initial regression of somatic program is followed by the gradual acquisition of pluripotent program. Oct4 preferatially binds to H3K4me1 marked enhancer regions and Oct4 binding is positively correlated with active mark H3K27ac. Moreover, we observed significant enhancer activation of epigenetic related genes, especially acetylation associated genes, prior to pluripotency network activation, suggesting a pivotal role of epigenetic remodelling in the process of pluripotency acquisition and maintenance.
2015-12-31 | GSE67520 | GEO