Project description:Esrrb is a transcription factor implicated in embryonic stem (ES) cell self-renewal, yet its knockout causes intrauterine lethality due to defects in trophoblast development. Here we show that in trophoblast stem (TS) cells, Esrrb is a downstream target of fibroblast growth factor (Fgf) signalling and is critical to drive TS cell self-renewal. In contrast to its occupancy of pluripotency-associated loci in ES cells, Esrrb sustains the stemness of TS cells by direct binding and regulation of TS cell-specific transcription factors including Elf5 and Eomes. To elucidate the mechanisms whereby Esrrb controls the expression of its targets, we characterized its TS cell-specific interactome by mass spectrometry. Unlike in ES cells, Esrrb interacts in TS cells with the histone demethylase Lsd1 and with the RNA Polymerase II-associated Integrator complex. Our findings provide new insights into both, the general and context-dependent wiring of transcription factor networks in stem cells by master transcription factors.
Project description:Trophoblast stem cells (TSCs) are derived from the trophoectoderm of a blastocyst and can maintain self-renewal in vitro. Meanwhile, essential insights into the molecular mechanisms controlling placental developmental could be gained by using TSCs that can differentiate into the various placental trophoblast cell types in vitro. Esrrb is a transcription factor with pivotal roles in maintaining TSCs’ self-renewal, but the exact transcriptional networks that Esrrb involved in TSCs are largely unknown. In the present study, we elucidated the function of Esrrb during TSC self-renewal and differentiation. We demonstrate that precise levels of Essrb are critical for TSCs stemness maintenance and normal trophoblast differentiation, as Esrrb depletion results in down-regulation of the key TSC-specific transcription factors, consequently causing TSCs differentiation and forced expression of Esrrb can partially block TSCs differentiation in the absence of FGF4. This function of Esrrb is exerted by directly binding and activating a core set of TSC-specific target genes including Cdx2, Eomes, Sox2, Fgfr4 and BMP4. Furthermore, we investigate the role of Esrrb in reprogramming of mouse embryonic fibroblasts (MEFs) to induced TSCs (iTSCs). We show that Esrrb can facilitate the conversion of iTSCs from MEFs. Moreover, Esrrb can substitute for Eomes during this conversion process. Our findings provide a better understanding of the molecular mechanism of Esrrb in maintaining TSCs self-renewal and iTSCs reprogramming.
Project description:Trophoblast stem cells (TSCs) are derived from the trophoectoderm of a blastocyst and can maintain self-renewal in vitro. Meanwhile, essential insights into the molecular mechanisms controlling placental developmental could be gained by using TSCs that can differentiate into the various placental trophoblast cell types in vitro. Esrrb is a transcription factor with pivotal roles in maintaining TSCs’ self-renewal, but the exact transcriptional networks that Esrrb involved in TSCs are largely unknown. In the present study, we elucidated the function of Esrrb during TSC self-renewal and differentiation. We demonstrate that precise levels of Essrb are critical for TSCs stemness maintenance and normal trophoblast differentiation, as Esrrb depletion results in down-regulation of the key TSC-specific transcription factors, consequently causing TSCs differentiation and forced expression of Esrrb can partially block TSCs differentiation in the absence of FGF4. This function of Esrrb is exerted by directly binding and activating a core set of TSC-specific target genes including Cdx2, Eomes, Sox2, Fgfr4 and BMP4. Furthermore, we investigate the role of Esrrb in reprogramming of mouse embryonic fibroblasts (MEFs) to induced TSCs (iTSCs). We show that Esrrb can facilitate the conversion of iTSCs from MEFs. Moreover, Esrrb can substitute for Eomes during this conversion process. Our findings provide a better understanding of the molecular mechanism of Esrrb in maintaining TSCs self-renewal and iTSCs reprogramming.
Project description:Chickarmane2006 - Stem cell switch reversible
Kinetic modeling approach of the transcriptional dynamics of the embryonic stem cell switch.
This model is described in the article:
Transcriptional dynamics of the embryonic stem cell switch.
Chickarmane V, Troein C, Nuber UA, Sauro HM, Peterson C
PLoS Computational Biology. 2006; 2(9):e123
Abstract:
Recent ChIP experiments of human and mouse embryonic stem cells have elucidated the architecture of the transcriptional regulatory circuitry responsible for cell determination, which involves the transcription factors OCT4, SOX2, and NANOG. In addition to regulating each other through feedback loops, these genes also regulate downstream target genes involved in the maintenance and differentiation of embryonic stem cells. A search for the OCT4-SOX2-NANOG network motif in other species reveals that it is unique to mammals. With a kinetic modeling approach, we ascribe function to the observed OCT4-SOX2-NANOG network by making plausible assumptions about the interactions between the transcription factors at the gene promoter binding sites and RNA polymerase (RNAP), at each of the three genes as well as at the target genes. We identify a bistable switch in the network, which arises due to several positive feedback loops, and is switched on/off by input environmental signals. The switch stabilizes the expression levels of the three genes, and through their regulatory roles on the downstream target genes, leads to a binary decision: when OCT4, SOX2, and NANOG are expressed and the switch is on, the self-renewal genes are on and the differentiation genes are off. The opposite holds when the switch is off. The model is extremely robust to parameter changes. In addition to providing a self-consistent picture of the transcriptional circuit, the model generates several predictions. Increasing the binding strength of NANOG to OCT4 and SOX2, or increasing its basal transcriptional rate, leads to an irreversible bistable switch: the switch remains on even when the activating signal is removed. Hence, the stem cell can be manipulated to be self-renewing without the requirement of input signals. We also suggest tests that could discriminate between a variety of feedforward regulation architectures of the target genes by OCT4, SOX2, and NANOG.
This model is hosted on BioModels Database
and identified by: MODEL7957907314
.
To cite BioModels Database, please use: BioModels Database: An enhanced, curated and annotated resource for published quantitative kinetic models
.
To the extent possible under law, all copyright and related or neighbouring rights to this encoded model have been dedicated to the public domain worldwide. Please refer to CC0 Public Domain Dedication
for more information.
Project description:Chickarmane2006 - Stem cell switch irreversible
Kinetic modeling approach of the transcriptional dynamics of the embryonic stem cell switch.
This model is described in the article:
Transcriptional dynamics of the embryonic stem cell switch.
Chickarmane V, Troein C, Nuber UA, Sauro HM, Peterson C
PLoS Computational Biology. 2006; 2(9):e123
Abstract:
Recent ChIP experiments of human and mouse embryonic stem cells have elucidated the architecture of the transcriptional regulatory circuitry responsible for cell determination, which involves the transcription factors OCT4, SOX2, and NANOG. In addition to regulating each other through feedback loops, these genes also regulate downstream target genes involved in the maintenance and differentiation of embryonic stem cells. A search for the OCT4-SOX2-NANOG network motif in other species reveals that it is unique to mammals. With a kinetic modeling approach, we ascribe function to the observed OCT4-SOX2-NANOG network by making plausible assumptions about the interactions between the transcription factors at the gene promoter binding sites and RNA polymerase (RNAP), at each of the three genes as well as at the target genes. We identify a bistable switch in the network, which arises due to several positive feedback loops, and is switched on/off by input environmental signals. The switch stabilizes the expression levels of the three genes, and through their regulatory roles on the downstream target genes, leads to a binary decision: when OCT4, SOX2, and NANOG are expressed and the switch is on, the self-renewal genes are on and the differentiation genes are off. The opposite holds when the switch is off. The model is extremely robust to parameter changes. In addition to providing a self-consistent picture of the transcriptional circuit, the model generates several predictions. Increasing the binding strength of NANOG to OCT4 and SOX2, or increasing its basal transcriptional rate, leads to an irreversible bistable switch: the switch remains on even when the activating signal is removed. Hence, the stem cell can be manipulated to be self-renewing without the requirement of input signals. We also suggest tests that could discriminate between a variety of feedforward regulation architectures of the target genes by OCT4, SOX2, and NANOG.
This model is hosted on BioModels Database
and identified by: MODEL7957942740
.
To cite BioModels Database, please use: BioModels Database: An enhanced, curated and annotated resource for published quantitative kinetic models
.
To the extent possible under law, all copyright and related or neighbouring rights to this encoded model have been dedicated to the public domain worldwide. Please refer to CC0 Public Domain Dedication
for more information.
Project description:Cellular differentiation requires cells to undergo dramatic but strictly controlled changes in chromatin organization, transcriptional regulation, and protein production and interaction. To understand the regulatory connections between these processes, we applied a multi-omics approach integrating proteomic, transcriptomic, chromatin accessibility, protein occupancy, and protein-chromatin interaction data acquired during differentiation of mouse embryonic stem cells (ESCs) into post-mitotic neurons. We found extensive remodeling of the chromatin that was preceding changes on RNA and protein levels. We found the pluripotency factor Sox2 as regulator of neuron-specific genes and, as a potential mechanism, revealed its genomic redistribution from pluripotency enhancers to neuronal promoters and concomitant change of its protein interaction network upon differentiation. We identified Atrx as a major Sox2 partner in neurons, whose co-localisation correlated with an increase in active enhancer marks and increased expression of nearby genes, and where deletion of a Sox2-Atrx co-bound site resulted in reduced expression of the proximal gene. Collectively, these findings provide key insights into the regulatory transformation of Sox2 during neuronal differentiation and highlight the significance of multi-omic approaches in understanding gene regulation in complex systems.
Project description:Porcine induced pluripotent stem cells (piPSCs) could serve as a great model system for human stem cell pre-clinical research. However, the pluripotency gene network of piPSCs, especially the function for the core transcription factor ESRRB, was poorly understood. Here, we constructed ESRRB-overexpressing piPSCs (ESRRB-piPSCs). Compared with the control piPSCs (CON-piPSCs), the ESRRB-piPSCs showed flat, monolayered colony morphology. Moreover, the ESRRB-piPSCs showed greater chimeric capacity into trophectoderm than CON-piPSCs. We found that ESRRB could directly regulate the expressions of trophoblast stem cell (TSC)-specific markers, including KRT8, KRT18 and CDX2, through binding to their promoter regions. Mutational analysis proved that the N-terminus zinc finger domain is indispensable for ESRRB to regulate the TSC markers. Furthermore, this regulation needs the participation of OCT4. Accordingly, the cooperation between ESRRB and OCT4 facilitates the conversion from pluripotent state to the trophoblast-like state.
Project description:To investigate the molecular mechanisms underlying the reprogramming of epiblast stem cells (EpiSCs) into embryonic stem cells (ESCs) induced by Esrrb, we performed ChIP-seq analysis of Esrrb, Nanog, Oct4, and Sox2 in Tet-on Esrrb EpiSCs after treatment with doxycycline (Dox).
Project description:During in vitro differentiation, pluripotent stem cells undergo extensive remodeling of their gene expression profiles. While studied extensively at the transcriptome level, much less is known about protein dynamics, which might differ significantly from their mRNA counterparts. Here, we present deep proteome-wide measurements of protein levels during the differentiation of embryonic stem cells.
Project description:Estrogen related receptor beta (Esrrb) is an orphan nuclear receptor that is required for self-renewal and pluripotency in mouse embryonic stem (ES) cells. However, in the early post-implantation mouse embryo, Esrrb is specifically expressed in the extraembryonic ectoderm (ExE) and plays a crucial role in trophoblast development. In this study, to better understand the function of Esrrb in trophoblast lineage cells, we performed microarray analysis of Esrrb-null mutant versus wild-type mouse embryos. To further characterize the regulatory targets of Esrrb, we treated trophoblast stem (TS) cells with either Esrrb inhibitor DES or vehicle and compared their global gene expression profile via RNA-seq analysis. In addition, to ask whether these target genes are directly regulated by Esrrb, we performed Chromatin immunoprecipitation-sequencing (ChIP-seq) analysis of TS cells using anti-Esrrb antibody.