Transcription factors that behave as master regulators during mammalian embryogenesis function as molecular rheostats

Three transcription factors, Sox2, Oct-3/4 and Nanog, have been identified as master regulators that orchestrate mammalian embryogenesis as well as the self-renewal and pluripotency of ES (embryonic stem) cells. Efforts to understand how these transcription factors function have shown that they have a special property in common. Small changes in the expression of any one of these factors dramatically alter the self-renewal and pluripotency of ES cells. In this way, each functions as a molecular rheostat to control the behaviour of ES cells. Recent studies have begun to examine the molecular mechanisms that regulate the levels of these transcription factors. In this issue of the Biochemical Journal, Mullin and co-workers report that Nanog can self-associate to form dimers. Importantly, they also show that the domain responsible for dimerization is also needed for Nanog to sustain the self-renewal of ES cells in the absence of the cytokine LIF (leukaemia inhibitory factor). On the basis of their studies, they propose a novel mechanism for regulating the interactions between Nanog and other nuclear proteins.

Download Full-text

182. NOVEL SIGNALLING IN MOUSE EMBRYONIC STEM CELLS GENERATES PRIMITIVE ECTODERM-LIKE CELLS

Reproduction Fertility and Development ◽

10.1071/srb09abs182 ◽

2009 ◽

Vol 21 (9) ◽

pp. 100

Author(s):

M. B. Morris ◽

N. Hamra ◽

A. C. Lonic ◽

F. Felquer

Keyword(s):

Es Cells ◽

Embryonic Stem ◽

Cell Types ◽

Leukaemia Inhibitory Factor ◽

Signalling Pathways ◽

Specific Cell ◽

Self Renewal ◽

Mouse Es Cells ◽

Homogeneous Production ◽

Extracellular Molecules

The phenotypic status of embryonic stem (ES) cells is controlled in part by signalling pathways which translate inputs mediated by extracellular molecules. An important extracellular protagonist in mouse ES cells is LIF (leukaemia inhibitory factor) which interacts with the gp130–LIFR receptor complex to activate a number of downstream signalling pathways, including the STAT3, MEK/ERK and PI3K/Akt. These pathways, together with others, interact in complex and sometimes competing ways to generate the well-known characteristics of mouse ES cells of self-renewal, high rates of proliferation, and pluripotence. The addition of a second molecule, L-proline, to the extracellular environment alters the pluripotent status of mouse ES cells, converting them to a second pluripotent population equivalent to the primitive ectoderm of the pre-gastrulating embryo. This conversion, from ES cells to primitive ectoderm-like cells, primes the latter for directed differentiation to specific cell types (1). Here we show, using inhibitor studies and kinome array analysis, that this small molecule appears to work by (i) changing the balance in activity of signalling pathways already stimulated by LIF and (ii) activating additional signalling pathways. Specifically, L-proline rapidly further activates the LIF-stimulated MEK/ERK pathway, tipping the balance in favour of primitive-ectoderm formation and away from ES-cell self-renewal sustained by LIF-mediated activation of the STAT3 pathway. In addition, L-proline rapidly stimulates other pathways including p38, mTOR and PI3K/Akt each of which contributes, to a greater or lesser extent, to the conversion to primitive ectoderm-like cells. These results indicate that (i) L-proline acts in novel ways to stimulate embryo-like developmental progression in ES cells and (ii) through the addition of small, nontoxic activators and inhibitors of signalling pathways, the differentiation of pluripotent ES cells might be controlled sufficiently well for the homogeneous production of specific cell types suitable for use in animal models of human disease.

Download Full-text

Fgf and Esrrb integrate epigenetic and transcriptional networks that regulate self-renewal of trophoblast stem cells

Nature Communications ◽

10.1038/ncomms8776 ◽

2015 ◽

Vol 6 (1) ◽

Cited By ~ 54

Author(s):

Paulina A. Latos ◽

Angela Goncalves ◽

David Oxley ◽

Hisham Mohammed ◽

Ernest Turro ◽

...

Keyword(s):

Stem Cells ◽

Transcription Factor ◽

Transcription Factors ◽

Rna Polymerase Ii ◽

Es Cells ◽

Embryonic Stem ◽

Transcriptional Networks ◽

Self Renewal ◽

Downstream Target ◽

Trophoblast Stem

Abstract Esrrb (oestrogen-related receptor beta) 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 using 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.

Download Full-text

Sox2 and Oct‐3/4: a versatile pair of master regulators that orchestrate the self‐renewal and pluripotency of embryonic stem cells

Wiley Interdisciplinary Reviews Systems Biology and Medicine ◽

10.1002/wsbm.12 ◽

2009 ◽

Vol 1 (2) ◽

pp. 228-236 ◽

Cited By ~ 96

Author(s):

Angie Rizzino

Keyword(s):

Stem Cells ◽

Embryonic Stem Cells ◽

Embryonic Stem ◽

The Self ◽

Self Renewal ◽

Master Regulators

Download Full-text

Repression of Nanog Gene Transcription by Tcf3 Limits Embryonic Stem Cell Self-Renewal

Molecular and Cellular Biology ◽

10.1128/mcb.00368-06 ◽

2006 ◽

Vol 26 (20) ◽

pp. 7479-7491 ◽

Cited By ~ 203

Author(s):

Laura Pereira ◽

Fei Yi ◽

Bradley J. Merrill

Keyword(s):

Stem Cells ◽

Transcription Factors ◽

Molecular Mechanisms ◽

Inner Cell Mass ◽

Cell Mass ◽

Regulatory Region ◽

Embryonic Stem ◽

Dual Function ◽

Self Renewal ◽

Nanog Gene

ABSTRACT The dual function of stem cells requires them not only to form new stem cells through self-renewal but also to form lineage-committed cells through differentiation. Embryonic stem cells (ESC), which are derived from the blastocyst inner cell mass, retain properties of self-renewal and the potential for lineage commitment. To balance self-renewal and differentiation, ESC must carefully control the levels of several transcription factors, including Nanog, Sox2, and Oct4. While molecular mechanisms promoting transcription of these genes have been described, mechanisms preventing excessive levels in self-renewing ESC remain unknown. By examining the function of the TCF family of transcription factors in ESC, we have found that Tcf3 is necessary to limit the steady-state levels of Nanog mRNA, protein, and promoter activity in self-renewing ESC. Chromatin immunoprecipitation and promoter reporter assays showed that Tcf3 bound to a promoter regulatory region of the Nanog gene and repressed its transcriptional activity in ESC through a Groucho interaction domain-dependent process. The absence of Tcf3 caused delayed differentiation of ESC in vitro as elevated Nanog levels persisted through 5 days of embryoid body formation. These new data support a model wherein Tcf3-mediated control of Nanog levels allows stem cells to balance the creation of lineage-committed and undifferentiated cells.

Download Full-text

SC1 Promotes MiR124-3p Expression to Maintain the Self-Renewal of Mouse Embryonic Stem Cells by Inhibiting the MEK/ERK Pathway

Cellular Physiology and Biochemistry ◽

10.1159/000485945 ◽

2017 ◽

Vol 44 (5) ◽

pp. 2057-2072 ◽

Cited By ~ 6

Author(s):

Qing Wei ◽

Hongliang Liu ◽

Zhiying Ai ◽

Yongyan Wu ◽

Yingxiang Liu ◽

...

Keyword(s):

Deep Sequencing ◽

Small Rna ◽

Es Cells ◽

Embryonic Stem ◽

The Self ◽

Erk Pathway ◽

Self Renewal ◽

Mouse Es Cells ◽

Rna Deep Sequencing ◽

Small Rna Deep Sequencing

Background/Aims: Self-renewal is one of the most important features of embryonic stem (ES) cells. SC1 is a small molecule modulator that effectively maintains the self-renewal of mouse ES cells in the absence of leukemia inhibitory factor (LIF), serum and feeder cells. However, the mechanism by which SC1 maintains the undifferentiated state of mouse ES cells remains unclear. Methods: In this study, microarray and small RNA deep-sequencing experiments were performed on mouse ES cells treated with or without SC1 to identify the key genes and microRNAs that contributed to self-renewal. Results: SC1 regulates the expressions of pluripotency and differentiation factors, and antagonizes the retinoic acid (RA)-induced differentiation in the presence or absence of LIF. SC1 inhibits the MEK/ERK pathway through Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis and pathway reporting experiments. Small RNA deep-sequencing revealed that SC1 significantly modulates the expression of multiple microRNAs with crucial functions in ES cells. The expression of miR124-3p is upregulated in SC1-treated ES cells, which significantly inhibits the MEK/ERK pathway by targeting Grb2, Sos2 and Egr1. Conclusion: SC1 enhances the self-renewal capacity of mouse ES cells by modulating the expression of key regulatory genes and pluripotency-associated microRNAs. SC1 significantly upregulates miR124-3p expression to further inhibit the MEK/ ERK pathway by targeting Grb2, Sos2 and Egr1.

Download Full-text

ZMYM2 inhibits NANOG-mediated reprogramming

Wellcome Open Research ◽

10.12688/wellcomeopenres.15250.1 ◽

2019 ◽

Vol 4 ◽

pp. 88 ◽

Cited By ~ 3

Author(s):

Moyra Lawrence ◽

Thorold W. Theunissen ◽

Patrick Lombard ◽

David J. Adams ◽

José C. R. Silva

Keyword(s):

Stem Cells ◽

Stem Cell ◽

Embryonic Stem Cell ◽

Somatic Cells ◽

Embryonic Stem ◽

The Self ◽

Negative Regulator ◽

Leukaemia Inhibitory Factor ◽

Self Renewal ◽

Epiblast Stem Cells

Background: NANOG is a homeodomain-containing transcription factor which forms one of the hubs in the pluripotency network and plays a key role in the reprogramming of somatic cells and epiblast stem cells to naïve pluripotency. Studies have found that NANOG has many interacting partners and some of these were shown to play a role in its ability to mediate reprogramming. In this study, we set out to analyse the effect of NANOG interactors on the reprogramming process. Methods: Epiblast stem cells and somatic cells were reprogrammed to naïve pluripotency using MEK/ERK inhibitor PD0325901, GSK3β inhibitor CHIR99021 and Leukaemia Inhibitory Factor (together termed 2i Plus LIF). Zmym2 was knocked out using the CRISPR/Cas9 system or overexpressed using the PiggyBac system. Reprogramming was quantified after ZMYM2 deletion or overexpression, in diverse reprogramming systems. In addition, embryonic stem cell self renewal was quantified in differentiation assays after ZMYM2 removal or overexpression. Results: In this work, we identified ZMYM2/ZFP198, which physically associates with NANOG as a key negative regulator of NANOG-mediated reprogramming of both epiblast stem cells and somatic cells. In addition, ZMYM2 impairs the self renewal of embryonic stem cells and its overexpression promotes differentiation. Conclusions: We propose that ZMYM2 curtails NANOG’s actions during the reprogramming of both somatic cells and epiblast stem cells and impedes embryonic stem cell self renewal, promoting differentiation.

Download Full-text

Pluripotency and differentiation of embryonic stem cells

E3S Web of Conferences ◽

10.1051/e3sconf/202018504034 ◽

2020 ◽

Vol 185 ◽

pp. 04034

Author(s):

Yinyin Liu ◽

Haibo Zhao ◽

Liang Liang ◽

Peilei Fan ◽

Yujia Zhao ◽

...

Keyword(s):

Transcription Factors ◽

Regenerative Medicine ◽

Inner Cell Mass ◽

Es Cells ◽

Cell Mass ◽

Embryonic Stem ◽

Early Embryo ◽

Self Renewal ◽

Extracellular Signals ◽

And Function

Mouse embryonic stem (ES) cells derive from the inner cell mass of an early embryo called blastocyst, making them promising resource for regenerative medicine. They possess two unique properties: self-renewal and pluripotency. Different ways can be used to assess which extracellular signal and factor inside ES cells has an impact on the pluripotency of ES cells. Nowadays, many extracellular signals and transcription factors have been identified, such as extracellular signals like LIF and transcription factors like Oct4. Studying the mechanism and function of these factors offers great insight and advance our understanding of pluripotency and self-renewal and thus shed light on regenerative medicine.

Download Full-text

Zic3 Is Required for Maintenance of Pluripotency in Embryonic Stem Cells

Molecular Biology of the Cell ◽

10.1091/mbc.e06-07-0624 ◽

2007 ◽

Vol 18 (4) ◽

pp. 1348-1358 ◽

Cited By ~ 85

Author(s):

Linda Shushan Lim ◽

Yuin-Han Loh ◽

Weiwei Zhang ◽

Yixun Li ◽

Xi Chen ◽

...

Keyword(s):

Stem Cells ◽

Transcription Factors ◽

Embryonic Stem Cells ◽

Regulatory Networks ◽

Molecular Mechanisms ◽

Es Cells ◽

Embryonic Stem ◽

Es Cell ◽

Lineage Specification ◽

Mouse Es Cells

Embryonic stem (ES) cell pluripotency is dependent upon sustained expression of the key transcriptional regulators Oct4, Nanog, and Sox2. Dissection of the regulatory networks downstream of these transcription factors has provided critical insight into the molecular mechanisms that regulate ES cell pluripotency and early differentiation. Here we describe a role for Zic3, a member of the Gli family of zinc finger transcription factors, in the maintenance of pluripotency in ES cells. We show that Zic3 is expressed in ES cells and that this expression is repressed upon differentiation. The expression of Zic3 in pluripotent ES cells is also directly regulated by Oct4, Sox2, and Nanog. Targeted repression of Zic3 in human and mouse ES cells by RNA interference–induced expression of several markers of the endodermal lineage. Notably, the expression of Nanog, a key pluripotency regulator and repressor of extraembryonic endoderm specification in ES cells, was significantly reduced in Zic3 knockdown cells. This suggests that Zic3 may prevent endodermal marker expression through Nanog-regulated pathways. Thus our results extend the ES cell transcriptional network beyond Oct4, Nanog, and Sox2, and further establish that Zic3 plays an important role in the maintenance of pluripotency by preventing endodermal lineage specification in embryonic stem cells.

Download Full-text

MicroRNAs and Stem-like Properties: The Complex Regulation Underlying Stemness Maintenance and Cancer Development

Biomolecules ◽

10.3390/biom11081074 ◽

2021 ◽

Vol 11 (8) ◽

pp. 1074

Author(s):

Giuseppina Divisato ◽

Silvia Piscitelli ◽

Mariantonietta Elia ◽

Emanuela Cascone ◽

Silvia Parisi

Keyword(s):

Stem Cells ◽

Molecular Mechanisms ◽

Epithelial Mesenchymal Transition ◽

Embryonic Stem ◽

Cell Types ◽

Cancer Development ◽

Special Focus ◽

Self Renewal ◽

Mesenchymal Transition ◽

Different Cell Types

Embryonic stem cells (ESCs) have the extraordinary properties to indefinitely proliferate and self-renew in culture to produce different cell progeny through differentiation. This latter process recapitulates embryonic development and requires rounds of the epithelial–mesenchymal transition (EMT). EMT is characterized by the loss of the epithelial features and the acquisition of the typical phenotype of the mesenchymal cells. In pathological conditions, EMT can confer stemness or stem-like phenotypes, playing a role in the tumorigenic process. Cancer stem cells (CSCs) represent a subpopulation, found in the tumor tissues, with stem-like properties such as uncontrolled proliferation, self-renewal, and ability to differentiate into different cell types. ESCs and CSCs share numerous features (pluripotency, self-renewal, expression of stemness genes, and acquisition of epithelial–mesenchymal features), and most of them are under the control of microRNAs (miRNAs). These small molecules have relevant roles during both embryogenesis and cancer development. The aim of this review was to recapitulate molecular mechanisms shared by ESCs and CSCs, with a special focus on the recently identified classes of microRNAs (noncanonical miRNAs, mirtrons, isomiRs, and competitive endogenous miRNAs) and their complex functions during embryogenesis and cancer development.

Download Full-text