ABSTRACT: Leukemia Inhibitory Factor (LIF) plays an essential role in the maintenance of pluripotency of mouse embryonic stem cells (mESCs). LIF withdrawal induces mESC differentiation. To define noval pluripotent factors downstream of LIF signaling, cDNA microarray was used and seveal well-known pluripotent genes were found to respond to LIF withdrawal, including Klf4, Esrrb, Tbx3, and Prdm14. mESCs were cultured in presence or absence of LIF for two days and RNAs extracted from these cells were subjected to microarray analysis
Project description:Leukemia Inhibitory Factor (LIF) plays an essential role in the maintenance of pluripotency of mouse embryonic stem cells (mESCs). LIF withdrawal induces mESC differentiation. To define noval pluripotent factors downstream of LIF signaling, cDNA microarray was used and seveal well-known pluripotent genes were found to respond to LIF withdrawal, including Klf4, Esrrb, Tbx3, and Prdm14.
Project description:Mouse embryonic stem cells (mESCs) fluctuate between a naïve inner cell mass (ICM)-like state and a primed epiblast-like state of pluripotency in serum, but are harnessed exclusively in a distinctive, apparently more naïve state of pluripotency (the ground state) with inhibitors for mitogen-activated protein kinase (MAPK) and glycogen synthase kinase 3 pathways (2i). Understanding the mechanism ensuring a naïve state of pluripotency would be critical in realizing a full potential of ESCs. We show here that PRDM14, a PR domain-containing transcriptional regulator, ensures a naïve pluripotency by a dual mechanism: Antagonizing fibroblast growth factor receptor (FGFR) signaling that is activated paradoxically by the core transcriptional circuitry for pluripotency and directs a primed state and repressing de novo DNA methyltransferases that create a primed epiblast-like epigenome. PRDM14 exerts these functions by recruiting polycomb repressive complex 2 (PRC2) specifically to key targets and repressing their expression. Mouse Embryonic Stem Cells (mESCs) or mESC-like cells with different Prdm14 genotypes {Prdm14(+/+), Prdm14(-/-), and Prdm14(-/-) rescued with Avitag-EGFP-Prdm14 transgene [Prdm14(-/-)+AGP14]} are cultured on MEF in different medium [2i, Serum(day 2), Serum+MEK inhibitor (PD0325901) (day 2), Serum without LIF (day2)].
Project description:Tbx3, a member of the T-box family, plays important roles in development, stem cells, nuclear reprogramming and cancer. Loss of Tbx3 induces differentiation in mouse embryonic stem cells (mESCs). However, we show that mESCs exist in an alternate stable pluripotent state in the absence of Tbx3. In-depth transcriptome analysis of this mESC state reveals Dppa3 as a direct downstream target of Tbx3. Also Tbx3 facilitates the cell fate transition from pluripotent cells to mesoderm progenitors by directly repressing Wnt pathway members required for differentiation. Wnt signaling regulates differentiation of mESCs into mesoderm progenitors and helps maintain a naïve pluripotent state. We show that Tbx3, a downstream target of Wnt signaling, fine-tunes these divergent roles of Wnt signaling in mESCs. In conclusion, we identify a signaling-TF axis that controls the exit of mESCs from a self-renewing pluripotent state towards mesoderm differentiation. ChIPSeq and RNASeq (population and single cell) was performed on the indicated cell lines. Replicates are indicated as needed. The mm9 genome assembly was used. For single cell mRNA-Seq preparation, SSEA1+DAPI- mESCs were sorted and collected.
Project description:Transcriptomic analysis of mouse embryonic stem cells (mESC) maintained in the pluripotent state or allowed to differentiate for 3 or 7 days by leukaemia inhibitory factor (LIF) withdrawal.
Project description:The TET family of FE(II) and 2-oxoglutarate-dependent enzymes (Tet1/2/3) promote DNA demethylation by converting 5-methylcytosine to 5-hydroxymethylcytosine (5hmC), which they further oxidize into 5-formylcytosine and 5-carboxylcytosine. Tet1 is robustly expressed in mouse embryonic stem cells (mESCs) and has been implicated in mESC maintenance. Here we demonstrate that, unlike genetic deletion, RNAi-mediated depletion of Tet1 in mESCs led to a significant reduction in 5hmC and loss of mESC identity. The differentiation phenotype due to Tet1 depletion positively correlated with the extent of 5hmC loss. Meta-analyses of genomic datasets suggested interaction between Tet1 and leukemia inhibitory factor (LIF) signaling. LIF signaling is known to promote self-renewal and pluripo-tency in mESCs partly by opposing MAPK/ERK mediated differentiation. Withdrawal of LIF leads to differentiation of mESCs. We discovered that Tet1 depletion impaired LIF-dependent Stat3-mediated gene activation by affecting Stat3's ability to bind to its target sites on chromatin. Nanog overexpression or inhibition of MAPK/ERK signaling, both known to maintain mESCs in the absence of LIF, rescued Tet1 depletion, further supporting the dependence of LIF/Stat3 signaling on Tet1. These data support the conclusion that analysis of mESCs in the hours/days immediately following efficient Tet1 depletion reveals Tet1’s normal physiological role in maintaining the pluripotent state that may be subject to homeostatic compensation in genetic models. Genome-wide mapping of 5hmC and microarray gene expression profiling in E14Tg2a mESCs after transfection with indicated siRNAs: Tet1 siRNA #1 (Invitrogen, MSS284895), Tet1 siRNA #2 (Invitrogen, MSS284897), and Control siRNA duplex targeting firefly luciferase.
Project description:Tbx3, a member of the T-box family, plays important roles in development, stem cells, nuclear reprogramming and cancer. Loss of Tbx3 induces differentiation in mouse embryonic stem cells (mESCs). However, we show that mESCs exist in an alternate stable pluripotent state in the absence of Tbx3. In-depth transcriptome analysis of this mESC state reveals Dppa3 as a direct downstream target of Tbx3. Also Tbx3 facilitates the cell fate transition from pluripotent cells to mesoderm progenitors by directly repressing Wnt pathway members required for differentiation. Wnt signaling regulates differentiation of mESCs into mesoderm progenitors and helps maintain a naïve pluripotent state. We show that Tbx3, a downstream target of Wnt signaling, fine-tunes these divergent roles of Wnt signaling in mESCs. In conclusion, we identify a signaling-TF axis that controls the exit of mESCs from a self-renewing pluripotent state towards mesoderm differentiation.
Project description:Transcriptional profiling of XiGFP Epiblast Stem Cells (EpiSCs) overexpressing Klf2, Prdm14, Prdm14+Klf2, or vector control. Cells cultured in activin and bFGF (day 0) or on day 2 and day 4 after transfer to serum and LIF on feeder cells and sorting for dsRed expression to remove feeder cells.
Project description:Naive pluripotent embryonic stem cells (ESCs) and embryonic germ cells (EGCs) are derived from the preimplantation epiblast and primordial germ cells (PGCs), respectively. We investigated whether differences exist between ESCs and EGCs, in view of their distinct developmental origins. PGCs are programmed to undergo global DNA demethylation; however, we find that EGCs and ESCs exhibit equivalent global DNA methylation levels. Importantly, inhibition of Erk and Gsk3b by 2i conditions leads to pronounced reduction in DNA methylation in both cell types. This is driven by Prdm14 and is associated with downregulation of Dnmt3a and Dnmt3b. However, genomic imprints are maintained in 2i, and we report derivation of EGCs with intact genomic imprints. Collectively, our findings establish that culture in 2i instills a naive pluripotent state with a distinctive epigenetic configuration that parallels molecular features observed in both the preimplantation epiblast and nascent PGCs. EGC lines were derived from E8.5 mouse embryos using three different protocols: FCS+LIF on MEFs (FCS, n = 4)), FCS+LIF on MEFs for 48 hours followed by 2i+LIF (2is, n = 4), and direct derivation into 2i+LIF (2i, n = 4). ESC lines were derived in either FCS+LIF on MEFs or in 2i+LIF conditions and once established the cell lines were also switched between the two culture environments (n = 5 for each culture condition). All cell lines were derived from genetically identical embryos.
Project description:The TET family of FE(II) and 2-oxoglutarate-dependent enzymes (Tet1/2/3) promote DNA demethylation by converting 5-methylcytosine to 5-hydroxymethylcytosine (5hmC), which they further oxidize into 5-formylcytosine and 5-carboxylcytosine. Tet1 is robustly expressed in mouse embryonic stem cells (mESCs) and has been implicated in mESC maintenance. Here we demonstrate that, unlike genetic deletion, RNAi-mediated depletion of Tet1 in mESCs led to a significant reduction in 5hmC and loss of mESC identity. The differentiation phenotype due to Tet1 depletion positively correlated with the extent of 5hmC loss. Meta-analyses of genomic datasets suggested interaction between Tet1 and leukemia inhibitory factor (LIF) signaling. LIF signaling is known to promote self-renewal and pluripo-tency in mESCs partly by opposing MAPK/ERK mediated differentiation. Withdrawal of LIF leads to differentiation of mESCs. We discovered that Tet1 depletion impaired LIF-dependent Stat3-mediated gene activation by affecting Stat3's ability to bind to its target sites on chromatin. Nanog overexpression or inhibition of MAPK/ERK signaling, both known to maintain mESCs in the absence of LIF, rescued Tet1 depletion, further supporting the dependence of LIF/Stat3 signaling on Tet1. These data support the conclusion that analysis of mESCs in the hours/days immediately following efficient Tet1 depletion reveals Tet1’s normal physiological role in maintaining the pluripotent state that may be subject to homeostatic compensation in genetic models.
Project description:The TET family of FE(II) and 2-oxoglutarate-dependent enzymes (Tet1/2/3) promote DNA demethylation by converting 5-methylcytosine to 5-hydroxymethylcytosine (5hmC), which they further oxidize into 5-formylcytosine and 5-carboxylcytosine. Tet1 is robustly expressed in mouse embryonic stem cells (mESCs) and has been implicated in mESC maintenance. Here we demonstrate that, unlike genetic deletion, RNAi-mediated depletion of Tet1 in mESCs led to a significant reduction in 5hmC and loss of mESC identity. The differentiation phenotype due to Tet1 depletion positively correlated with the extent of 5hmC loss. Meta-analyses of genomic datasets suggested interaction between Tet1 and leukemia inhibitory factor (LIF) signaling. LIF signaling is known to promote self-renewal and pluripo-tency in mESCs partly by opposing MAPK/ERK mediated differentiation. Withdrawal of LIF leads to differentiation of mESCs. We discovered that Tet1 depletion impaired LIF-dependent Stat3-mediated gene activation by affecting Stat3's ability to bind to its target sites on chromatin. Nanog overexpression or inhibition of MAPK/ERK signaling, both known to maintain mESCs in the absence of LIF, rescued Tet1 depletion, further supporting the dependence of LIF/Stat3 signaling on Tet1. These data support the conclusion that analysis of mESCs in the hours/days immediately following efficient Tet1 depletion reveals Tet1’s normal physiological role in maintaining the pluripotent state that may be subject to homeostatic compensation in genetic models.