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Background Aims: Human pluripotent stem cells, including embryonic stem cells and induced pluripotent stem cells, offer groundbreaking therapeutic potential for degenerative diseases and cellular repair. Despite their significance, a comprehensive bibliometric analysis in this field, particularly in relation to age-related macular degeneration (AMD), is yet to be conducted. This study aims to map the foundational and emerging areas in stem cell and AMD research through bibliometric analysis., Methods: This study analyzed articles and reviews on stem cells and AMD from 2000 to 2022, sourced from the Web of Science Core Collection. We used VOSviewer and CiteSpace for analysis and visualization of data pertaining to countries, institutions, authors, journals, references and key words. Statistical analyses were conducted using R language and Microsoft Excel 365., Results: In total, 539 publications were included, indicating an increase in global literature on stem cells and AMD from 2000 to 2022. The USA was the leading contributor, with 239 papers and the highest H-index, also the USA had the highest average citation rate per article (59.82). Notably, 50% of the top 10 institutions were from the USA, with the University of California system being the most productive. Key authors included Masayo Takahashi, Michiko Mandai, Dennis Clegg, Pete J. Coffey, Boris Stanzel, and Budd A. Tucker. Investigative Ophthalmology & Visual Science published the majority of relevant papers (n = 27). Key words like "clinical trial," "stem cell therapy," "retinal organoid," and "retinal progenitor cells" were predominant., Conclusions: Research on stem cells and AMD has grown significantly, highlighting the need for increased global cooperation. Current research prioritizes the relationship between "ipsc," "induced pluripotent stem cell," "cell culture," and "human embryonic stem cell." As stem cell culture and safety have advanced, focus has shifted to prognosis and complications post-transplantation, signifying the movement of stem cell research from labs to clinical settings., Competing Interests: Declaration of Competing Interest The authors have no commercial, proprietary or financial interest in the products or companies described in this article., (Copyright © 2024 International Society for Cell & Gene Therapy. Published by Elsevier Inc. All rights reserved.)

As the most well-studied modification in mRNA, m 6 A has been shown to regulate multiple biological processes, including RNA degradation, processing, and translation. Recent studies showed that m 6 A modification is enriched in chromatin-associated RNAs and nascent RNAs, suggesting m 6 A might play regulatory roles in chromatin contexts. Indeed, in the past several years, a number of studies have clarified how m 6 A and its modulators regulate different types of chromatin states. Specifically, in the past 2-3 years, several studies discovered the roles of m 6 A and/or its modulators in regulating constitutive and facultative heterochromatin, shedding interesting lights on RNA-dependent heterochromatin formation in mammalian cells. This review will summarize and discuss the mechanisms underlying m 6 A's regulation in different types of heterochromatin, with a specific emphasis on the regulation in mammalian embryonic stem cells, which exhibit distinct features of multiple heterochromatin marks., Competing Interests: Declaration of Competing Interest None., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

This paper provides an identification and detailed assessment of hormetic dose responses of embryonic stem cells (ESCs) with particular emphasis on cell renewal (proliferation) and differentiation, underlying mechanistic foundations and potential therapeutic implications. Hormetic dose responses were commonly reported, being induced by a broad range of chemicals, including pharmaceuticals (e.g., atorvastatin, isoproterenol, lithium, nicotine, ouabain), dietary supplements (e.g., curcumin, multiple ginsenosides, resveratrol), endogenous agents (e.g., estrogen, hydrogen peroxide, melatonin), and physical stressor agents (e.g., hypoxia, ionizing radiation). ESC-hormetic dose responses are similar for other stem cell types (e.g., adipose-derived stem cells, apical papilla, bone marrow stem cells, dental pulp stem cells, endothelial stem cells, muscle stem cells, periodontal ligament stem cells, neural stem cells), indicating a high degree of generality for the hormetic-stem cells response. The widespread occurrence of hormetic dose responses shown by ESCs and other stem cells suggests that the hormetic dose response may represent a fundamental and highly conserved evolutionary strategy., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Rats have long been an ideal model for disease research in the field of biomedicine, but the bottleneck of in vitro culture of rat embryonic stem (ES) cells hindered the wide application as genetic disease models. Here, we optimized a special medium which we named 5N-medium for rat embryonic stem cells, which improved the in vitro cells with better morphology and higher pluripotency. We then established a drug selection schedule harboring a prior selection of 12 h that achieved a higher positive selection ratio. These treatments induced at least 50% increase of homologous recombination efficiency compared with conventional 2i culture condition. Moreover, the ratio of euploid ES clones also increased by 50% with a higher germline transmission rate. Finally, we successfully knocked in a 175 kb human Bacterial Artificial Chromosome (BAC) fragment to rat ES genome through recombinase mediated cassette exchange (RMCE). Hence, we provide a promising system for generating sophisticated rat models which could be benefit for biomedical researches., Competing Interests: Declaration of competing interest The authors have declared no conflict of interest., (Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.)

Age-dependent dysregulation of transcription regulatory machinery triggers modulations in the gene expression levels leading to the decline in cellular fitness. Tracking of these transcripts along the temporal axis in multiple species revealed a spectrum of evolutionarily conserved pathways, such as electron transport chain, translation regulation, DNA repair, etc. Recent shreds of evidence suggest that aging deteriorates the transcription machinery itself, indicating the hidden complexity of the aging transcriptomes. This reinforces the need for devising novel computational methods to view aging through the lens of transcriptomics. Here, we present Homeostatic Divergence Score (HDS) to quantify the extent of messenger RNA (mRNA) homeostasis by assessing the balance between spliced and unspliced mRNA repertoire in single cells. We validated its utility in two independent aging datasets, and identified sets of genes undergoing age-related breakdown of transcriptional homeostasis. Moreover, testing of our method on a subpopulation of human embryonic stem cells revealed a set of differentially processed transcripts segregating these subpopulations. Our preliminary analyses in this direction suggest that mRNA processing level information offered by single-cell RNA sequencing (scRNA-seq) data is a superior determinant of chronological age as compared to transcriptional noise., Competing Interests: Declaration of interest The authors declare no conflicts of interest., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Exposure to many kinds of bisphenols (BPs) is common, and the effects of BP mixtures may differ from those of individual BPs. Therefore, evaluating combined exposure effects is necessary. Our study evaluated the individual and combined exposure effects of bisphenol A (BPA), bisphenol S (BPS) and bisphenol AF (BPAF) on embryonic development using an embryonic stem cell test (EST) and a concentration additive (CA) model at relatively high doses to uncover the interaction model of the three BPs. Environmentally relevant concentrations were then used to evaluate the possible effects of the individual and combined BPs at actual human exposure levels. Exposure to relatively high-dose BPA, BPS and BPAF inhibited embryonic stem cell differentiation into cardiomyocytes and exhibited weak embryo toxicity. Individually, BPA, BPS and BPAF inhibited endoderm, mesoderm and ectoderm marker expression but enhanced pluripotency marker expression. Combined exposure to BPs had an additive effect on cardiomyocyte differentiation and embryonic stem cell proliferation based on the CA model. Environmentally relevant individual or combined BP doses (10 ng/ml individual BPA, BPS and BPAF doses or 1 ng/ml and 10 ng/ml BP mixture doses) failed to cause oxidative stress, DNA damage or apoptosis changes in stem cell differentiation. The cardiomyocyte differentiation ratio also did not change significantly. Individual and combined exposure to environmentally relevant BP doses led to a significant increase in collagen expression. BPAF and the combination of BPs increased the type 1 collagen level, while the combination also increased the type 3 collagen level, which may be related to p38 pathway activation. The p38 pathway inhibitor SB203580 inhibited the increase in collagen during cardiomyocyte differentiation caused by low-dose BPs. These results suggest that relatively high-dose BPs in combination have an additive effect on cardiomyocyte differentiation. Low-dose BPs individually and in combination may affect cardiomyocyte collagen through the p38 pathway., (Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.)

Surgical smoke is widespread in operating rooms, and fine particles are the main toxic components. However, the effect of fine particles in surgical smoke on embryonic development has not yet been studied. This study evaluated the effect of fine particles in surgical smoke on embryonic development and compared it with that of atmospheric fine particles. Afterwards, differentiated cardiomyocytes were purified, and the effect of exposure to fine particles in surgical smoke on cardiomyocyte differentiation was evaluated. Fine particles in surgical smoke exhibited weak embryotoxicity toward an embryonic stem cell test model, and their inhibitory effect on cardiomyocyte differentiation was slightly stronger than that of atmospheric fine particles. Fine particles in surgical smoke specifically inhibited the differentiation of the mesoderm lineage and promoted the differentiation of the ectoderm lineage. Furthermore, fine particles in surgical smoke reduced the beating rate of purified cardiomyocytes, promoted mitophagy, reduced ATP production and increased the reactive oxygen species (ROS) content. Antioxidants attenuated the inhibition of cardiomyocyte differentiation and the reduction in the cardiomyocyte beating rate caused by fine particles in surgical smoke and simultaneously restored mitophagy and other processes to the control levels. However, mitophagy inhibitors treatment blocked only the inhibition of cardiomyocyte differentiation caused by fine particles in surgical smoke; it had little effect on other changes caused by fine particles. Based on the results described above, we propose that fine particles in surgical smoke and atmospheric fine particles exhibit similar levels of toxicity toward embryonic development. Fine particles in surgical smoke potentially affect the beating of cardiomyocytes by damaging mitochondria and increasing oxidative stress., (Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.)

Recent advances in synthetic human embryology has provided a previously inexistent molecular portrait of human development. Models of synthetic human embryonic tissues capitalize on the self-organizing capabilities of human embryonic stem cells when they are cultured on biomimetic conditions that simulate in vivo human development. In this Review, we discuss these models and how they have shed light on the early stages of human development including amniotic sac development, gastrulation and neurulation. We discuss the mechanisms underlying the molecular logic of embryonic tissue self-organization that have been dissected using synthetic models of human embryology and explore future challenges in the field. Geared with technological advances in bioengineering, high resolution gene expression and imaging tools, these models are set to transform our understanding of the mechanistic basis of embryonic tissue self-organization during human development and how they may go awry in disease., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Early human post-implantation development involves extensive growth combined with a series of complex morphogenetic events. The lack of precise spatial and temporal control over these processes leads to pregnancy loss. Given the ethical and technical limitations in studying the natural human embryo, alternative approaches are needed to investigate mechanisms underlying this critical stage of human development. Here, we present an overview of the different stem cells and stem cell-derived models which serve as useful, albeit imperfect, tools in understanding human embryogenesis. Current models include stem cells that represent each of the three earliest lineages: human embryonic stem cells corresponding to the epiblast, hypoblast-like stem cells and trophoblast stem cells. We also review the use of human embryonic stem cells to model complex aspects of epiblast morphogenesis and differentiation. Additionally, we propose that the combination of both embryonic and extra-embryonic stem cells to form three-dimensional embryo models will provide valuable insights into cell-cell chemical and mechanical interactions that are essential for natural embryogenesis., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Animal-free assessment of compound-induced developmental neurotoxicity will most likely be based on batteries of multiple in vitro tests. The optimal battery is built by combining tests with complementary biological domains that together ideally cover all relevant toxicity pathways. Thus, biological domain definition, i.e. which biological processes and cell types are represented, is an important assay characteristic for determining the place of assays in testing strategies. The murine neural embryonic stem cell test (ESTn) is employed to predict the developmental neurotoxicity of compounds. The aim of this study was to explore the biological domain of ESTn according to three groups of biomarker genes of early (neuro)development: morphogenetic regulators, Hox genes and cell type markers for the ectodermal and neural lineages. These biomarker groups were selected based on their crucial regulatory role in (neuro)development. Analysis of these genes in a series of previously generated whole transcriptome datasets of ESTn showed that at day 7 in culture cell differentiation resembled hindbrain/branchial/thoracic development between E6.5-E12.5 in vivo, with subsequent development into a mixed cell culture containing different neural subtypes, astrocytes and oligodendrocytes by day 13. In addition, the selected biomarkers showed common and distinct responses to compound exposure. Monitoring the biological domain of ESTn through gene expression patterns of morphogenetic regulators, Hox genes and cell type markers proved instrumental in providing mechanistic understanding of compound effects on neural differentiation in ESTn, and can aid in positioning of the test in a battery of complementary in vitro tests in integrated approaches to testing and assessment., (Copyright © 2021 Elsevier B.V. All rights reserved.)

At implantation, the mouse embryo undergoes a critical transformation which requires the precise spatiotemporal control of signalling pathways necessary for morphogenesis and developmental progression. The role played by such signalling pathways during this transition are largely unexplored, due to the inaccessibility of the embryo during the implantation when it becomes engulfed by uterine tissues. Genetic studies demonstrate that mutant embryos for BMPs die around gastrulation. Here we have aimed to dissect the role of BMPs during pre-to post-implantation transition by using a protocol permitting the development of the embryo beyond implantation stages in vitro and using stem cells to mimic post-implantation tissue organisation. By assessing both the canonical and non-canonical mechanisms of BMP, we show that the loss of canonical BMP activity compromises the extra-embryonic ectoderm development. Our analyses demonstrate that BMP signalling maintains stem cell populations within both embryonic/extra-embryonic tissues during pre-to post-implantation development. These results may provide insight into the role played by BMP signalling in controlling early embryogenesis., Competing Interests: Declaration of competing interest The authors declare no competing or financial interests., (Published by Elsevier Inc.)

Nuclear transporter Importin (Imp, Ipo) 13 is known to transport various mammalian cargoes into/out of the nucleus, but its role in directing cell-fate is unclear. Here we examine the role of Imp13 in the maintenance of pluripotency and differentiation of embryonic stem cells (ESCs) for the first time, using an embryonic body (EB)-based model. When induced to differentiate, Ipo13 -/- ESCs displayed slow proliferation, reduced EB size, and lower expression of the proliferation marker KI67, concomitant with an increase in the number of TUNEL + nuclei compared to wildtype ESCs. At days 5 and 10 of differentiation, Ipo13 -/- EBs also showed enhanced loss of the pluripotency transcript OCT3/4, and barely detectable clusters of OCT3/4 positive cells. Day 5 Ipo13 -/- EBs further exhibited reduced levels of the mesodermal markers Brachyury and Mixl1, correlating with reduced numbers of haemoglobinised cells generated. Our findings suggest that Imp13 is critical to ESC survival as well as early post-gastrulation differentiation., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2020 Elsevier Inc. All rights reserved.)

We previously demonstrated that AKR vs. DBA/2 mouse bone marrow derived macrophages have higher levels of free cholesterol and lower levels of esterified cholesterol after cholesterol loading, and that AKR, but not DBA/2, macrophages induced C/EBP homologous protein (CHOP) expression after cholesterol loading. We earlier determined that the free and esterified cholesterol level effect is due to a truncation in the sterol O-acyltransferase 1 (Soat1) gene, encoding acetyl-coenzyme A acetyltransferase 1 (ACAT1). Here we examined the mechanism for the differential induction of CHOP by cholesterol loading. CHOP was induced in both strains after incubation with tunicamycin, indicating both strains have competent endoplasmic reticulum stress pathways. CHOP was induced when DBA/2 macrophages were cholesterol loaded in the presence of an ACAT inhibitor, indicating that the difference in free cholesterol levels were responsible for this strain effect. This finding was confirmed in macrophages derived from DBA/2 embryonic stem cells. Cholesterol loading of Soat1 gene edited cells, mimicking the AKR allele, led to increased free cholesterol levels and restored CHOP induction. The upstream pathway of free cholesterol induced endoplasmic reticulum stress was investigated; and, RNA-dependent protein kinase-like endoplasmic reticulum kinase (PERK) and inositol-requiring enzyme 1 α protein kinase (IRE1α) pathways were required for maximal CHOP expression., (Copyright © 2020 Elsevier B.V. All rights reserved.)

The methylcytosine oxidase TET proteins play important roles in DNA demethylation and development. In developing embryos, TET2 are upregulated during pre-implantation development, and significantly expressed in the trophectoderm and inner cell mass. In this study, we identified Barx2 as a new target of Tet2. Tet2 bound and demethylated the promoter of Barx2 in mouse embryonic stem cells (mESCs) to maintain the expression of Barx2. During mESC differentiation, Tet2 bound the promoter of Barx2 in day 4 embryonic bodies but not in day 8 EBs. However, Barx2 expression remained unchanged. Thus, Tet2 functioned as a demethylase and maintained the expression of Barx2 in undifferentiated and early differentiated mESCs., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Inc. All rights reserved.)

The DNA demethylase TET1 is highly expressed in embryonic stem cells and is important both for lineage commitment, and reprogramming to naïve pluripotency. TET1 interacts with the pluripotency transcription factor NANOG which may contribute to its biological activity in pluripotent cells. However, how TET1 interacts with other proteins is largely unknown. Here, we characterise the physical interaction between TET1 and NANOG using embryonic stem cells and bacterial expression systems. TET1 and NANOG interact through multiple binding sites that act independently. Critically, mutating conserved hydrophobic and aromatic residues within TET1 and NANOG abolishes the interaction. On chromatin, NANOG is predominantly localised at ESC enhancers. While TET1 binds to CpG dinucleotides in promoters using its CXXC domain, TET1 also binds to enhancers, though the mechanism involved is unknown. Comparative ChIP-seq analysis identifies genomic loci bound by both TET1 and NANOG, that correspond predominantly to pluripotency enhancers. Importantly, around half of NANOG transcriptional target genes are associated with TET1-NANOG co-bound sites. These results indicate a mechanism by which TET1 protein may be targeted to specific sites of action at enhancers by direct interaction with a transcription factor., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Multicellular organisms develop from a single cell, the zygote. This feature is referred to as totipotency. In the mouse, only the zygote and the 2-cell stage embryo display this attribute. Cells resembling the embryonic 2-cell stage blastomeres were identified in embryonic stem (ES) cell cultures as '2-cell-like cells' (2CLCs). This discovery brought the first cellular model with the possibility to investigate some features of the totipotent embryo and the molecular mechanisms regulating totipotency in vitro. In this article, we discuss the latest advancements on the research on 2CLCs, which have uncovered an intricate reprogramming process regulated by proteins as well as metabolites and ncRNAs. These recent findings have shed light on the combinatorial regulation of 2-cell-like cell emergence and the nature of their unique attributes., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

How does an embryo acquire totipotency and develop into an adult is a fundamental scientific question. Stem cells derived from pre-implantation embryos or reprogrammed from somatic cells with totipotency features have been established. They have enriched molecular features, including transcription, epigenetic modification, chromatin structure and metabolism, similar to early embryos from 2 cell (2C) to morula. Functionally, they display a broader developmental potential to differentiate into cell types in the embryonic and extraembryonic tissues. The expanded developmental potential was further demonstrated by inducing these stem cells into embryo-like structures alone or aggregating with other embryo-derived stem cells. The synthetic embryo-like structures not only facilitate the dissection of key events in early embryonic development, but also serve as a model for investigating pregnancy related complications., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

After fertilization, mouse embryos go through preimplantation development to give rise to blastocyst. Two key molecular events, zygotic genome activation (ZGA) and the first cell lineage specification, are essential for the process. Recent advances in low-input epigenomics profiling techniques allow the analysis of these events at a molecular level, which revealed a critical role of epigenetic and chromatin reprogramming in ZGA and the first cell lineage specification. Additionally, the establishment of an in vitro embryonic stem cell (ESC) to two-cell embryo-like conversion system have also contributed to the molecular understanding of preimplantation development. In this review, we summarize recent advances in epigenetic regulation of mouse preimplantation development, point out the remaining questions, and propose strategies to tackle these questions., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

The placenta is an essential organ for the fetus, but its regulatory mechanism for formation of functional trophoblast lineage remains elusive in humans. Although widely known in mice, TEAD4 and its downstream targets CDX2 and GATA3 have not been determined in human models. In this work, we used a human model of trophoblast transition from BAP (BMP4, A83-01 and PD173074)-treated human embryonic stem cells (hESCs) and performed multiple gain- and loss-of-function tests of TEAD4, CDX2 or GATA3 to study their roles during this process. Although hESCs with TEAD4 deletion maintain pluripotency, their trophoblast transition potentials are attenuated. This impaired trophoblast transition could be rescued by separately overexpressing TEAD4, CDX2 or GATA3. Furthermore, trophoblast transition from hESCs is also attenuated by knockout of CDX2 but remains unaffected with deletion of GATA3. However, CDX2-overexpressed hESCs maintain pluripotency, whereas overexpression of GATA3 in hESCs leads to spontaneous differentiation including trophoblast lineage. In brief, our findings using a human model of trophoblast transition from BAP-treated hESCs reveal transcription roles of TEAD4, CDX2 and GATA in humans that are different from those in mice. We hope that this evidence can aid in understanding the distinct transcriptional network regulating trophoblast development in humans., Competing Interests: Declaration of competing interest The authors of this paper declare no conflict of interest., (Copyright © 2020 Elsevier B.V. All rights reserved.)

The importance of oxygen tension in in vitro cultures and its effect on embryonic stem cell (ESC) differentiation has been widely acknowledged. Research has mainly focussed on ESC maintenance or on one line of differentiation and only few studies have examined the potential relation between oxygen tension during ESC maintenance and differentiation. In this study we investigated the influence of atmospheric (20%) versus physiologic (5%) oxygen tension in ESC cultures and their differentiation within the cardiac and neural embryonic stem cell tests (ESTc, ESTn). Oxygen tension was set at 5% or 20% and cells were kept in these conditions from starting up cell culture until use for differentiation. Under these oxygen tensions, ESC culture showed no differences in proliferation and gene and protein expression levels. Differentiation was either performed in the same or in the alternative oxygen tension compared to ESC culture creating four different experimental conditions. Cardiac differentiation in 5% instead of 20% oxygen resulted in reduced development of spontaneously beating cardiomyocytes and lower expression of cardiac markers Nkx2.5, Myh6 and MF20 (myosin), regardless whether ESC had been cultured in 5% or 20% oxygen tension. As compared to the control (20% oxygen during stem cell maintenance and differentiation), neural differentiation in 5% oxygen with ESC cultured in 20% oxygen led to more cardiac and neural crest cell differentiation. The opposite experimental condition of neural differentiation in 20% oxygen with ESC cultured in 5% oxygen resulted in more glial differentiation. ESC that were maintained and differentiated in 5% oxygen showed an increase in neural crest and oligodendrocytes as compared to 20% oxygen during stem cell maintenance and differentiation. This study showed major effects on ESC differentiation in ESTc and ESTn of oxygen tension, which is an important variable to consider when designing and developing a stem cell-based in vitro system., (Copyright © 2020 International Society of Differentiation. Published by Elsevier B.V. All rights reserved.)

Glucocorticoids can promote cardiomyocyte maturation. However, the mechanism underlying glucocorticoid-mediated cardiomyocyte maturation is still unclear. Mitophagy plays a key role in cardiomyocyte maturation. Based on current knowledge, our study evaluated the effects of the glucocorticoid dexamethasone (100 nM) on the maturation of mouse embryonic stem cell-derived cardiomyocytes and the role of mitophagy in this maturation. The results showed that dexamethasone can promote embryonic stem cell-derived cardiomyocyte maturation, inhibit cardiomyocyte proliferation, and promote myocardial fiber arrangement. However, dexamethasone did not affect mitochondrial morphology in cardiomyocytes. Glucocorticoid receptor inhibitors (RU486, 1 nM) can inhibit dexamethasone-mediated cardiomyocyte maturation. Additionally, dexamethasone can promote mitophagy in embryonic stem cell-derived cardiomyocytes and induce LC3 and lysosomal aggregation in mitochondria. The inhibition of mitophagy can inhibit the cardiomyocyte maturation effect of dexamethasone. Furthermore, our research found that dexamethasone may mediate the occurrence of mitophagy in cardiomyocytes through Parkin. The siRNA-mediated inhibition of Parkin expression can inhibit mitochondrial autophagy caused by dexamethasone, thus inhibiting cardiomyocyte maturation. Overall, our study found that dexamethasone can promote embryonic stem cell-derived cardiomyocyte maturation through Parkin-mediated mitophagy., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Study of early human embryo development is essential for advancing reproductive and regenerative medicine. Traditional human embryological studies rely on embryonic tissue specimens, which are difficult to acquire due to technical challenges and ethical restrictions. The availability of human stem cells with developmental potentials comparable to pre-implantation and peri-implantation human embryonic and extraembryonic cells, together with properly engineered in vitro culture environments, allow for the first time researchers to generate self-organized multicellular structures in vitro that mimic the structural and molecular features of their in vivo counterparts. The development of these stem cell-based, synthetic human embryo models offers a paradigm-shifting experimental system for quantitative measurements and perturbations of multicellular development, critical for advancing human embryology and reproductive and regenerative medicine without using intact human embryos., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

The common marmoset (marmoset; Callithrix jacchus) harbors various desired features as a non-human primate (NHP) model for neuroscience research. Recently, efforts have been made to induce neural cells in vitro from marmoset pluripotent stem cells (PSCs), including embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs), which are characterized by their capacity to differentiate into all cell types from the three germ layers. Successful generation of marmoset neural cells is not only invaluable for understanding neural development and for modeling neurodegenerative and psychiatric disorders, but is also necessary for the phenotypic screening of genetically-modified marmosets. However, differences in the differentiation propensity among PSC lines hamper the applicability and the reproducibility of differentiation methods. To overcome this limitation, we evaluated the efficacy of small molecules for neural differentiation of marmoset ESCs (cjESCs) and iPSCs using multiple differentiation methods. By immunochemical and transcriptomic analyses, we confirmed that our methods using the small molecules are efficient for various differentiation protocols by either enhancing the yield of a mixture of neural cells including both neurons and glial cells, or a pure population of neurons. Collectively, our findings optimized in vitro neural differentiation methods for marmoset PSCs, which would ultimately help enhance the utility of the animal model in neuroscience., (Copyright © 2019 Elsevier B.V. and Japan Neuroscience Society. All rights reserved.)

Stem cells are crucial in the field of tissue regeneration and developmental biology. Embryonic stem cells (ESCs) which are pluripotent in nature are derived from the inner cell mass of blastocyst. The gene expression profiles of ESCs and Induced pluripotent stem cells (iPSCs) were compared to identify the differences. Spermatogonial stem cells (SSCs) are also known as Germ-line stem cells (GSCs) present in testis is having the capability of producing the sperm in their whole lifetime. Therefore can be reprogrammed into pluripotent cells called male germline pluripotent cells (gPSCs). It is very difficult to interpret the larger genomic data sets which are available in public databases without high computational facilities. In order to identify the similar groups We studied the co-expression, clustering of the transcriptome and variation of the transcriptome of the GSCs, gPSCs, ESCs and other cell types using fuzzy clustering using AutoSOME. The series matrix file with GSE ID GSE11274 was retrieved and subjected to the various normalization methods, corresponding rows and columns were clustered using p values, ensemble runs, and different running modes. Transcriptome analysis using the proposed approach intuitively and consistently characterized the variation in cell-cell significantly. Collectively, our results suggest that the GSCs and the ESCs displayed differential gene expression profiles, and the GSCs possessed the potential to acquire pluripotency based on the high expression of epigenetic factors and transcription factors. These data may provide novel insights into the reprogramming mechanism of GSCs., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Recently, it has become possible to recapitulate embryonic patterning in vitro using embryonic stem cells. The technical advantages and reduced complexity of these embryoids make them ideally suited to rigorously test long standing paradigms for pattern formation in the mammalian embryo. Here, we discuss insights into the underlying mechanisms that have been gained from stem cell models to date, focusing on models for gastrulation., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Introduction: The first lineage separation in mammalian development occurs when totipotent cells of the zygote give rise to the inner cell mass and the trophectoderm. The lineages are strictly separated by an epigenetic barrier. In vitro derivatives of these lineages embryonic stem cells (ESC) and trophoblast stem cells (TSC) are used to study the requirements needed to overcome the barrier in ESC to TSC conversion approaches., Methods: Different combinations of TSC transcription factors were induced in ESC for three days. Cells were kept in TS medium with fetal bovine serum (FBS) or the chemically defined TX medium. Obtained cells were analysed for OCT4 levels, TSC surface marker levels, expression of TSC markers and methylation status of Elf5, Oct4 and Nanog promoters. Further, long-term culture stability and in vitro and in vivo differentiation was tested., Results: Overexpression of Gata3, Eomes, Tfap2c, Ets2 and Cdx2 in ESC resulted in induction of TSC fate. Overexpression of Cdx2 or four factors (Gata3, Eomes, Tfap2c and Ets2) resulted in complete conversion only when cells were cultured in TX medium. The obtained induced TSC (iTSC) display characteristics of bona fide TSC in terms of marker expression and promoter methylation patterns. The generated converted cells were shown to display self-renewal and to be capable to differentiate into TSC derivatives in vitro and in vivo., Conclusion: Gata3, Eomes, Tfap2c, Ets2 and Cdx2 overexpression in ESC resulted in stable iTSC fate independent of culture conditions. For four factors or Cdx2 alone, TX medium is required for complete TSC conversion., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

It has become clear during recent years that stem cells undergo metabolic remodeling during their activation process. While these metabolic switches take place in pluripotency as well as adult stem cell populations, the rules that govern the switch are not clear. In this review, we summarize some of the transitions in adult and pluripotent cell types and will propose that the key function in this process is the generation of epigenetic metabolites that govern critical epigenetic modifications, and therefore stem cell states., (© 2020 Elsevier Inc. All rights reserved.)

Morphogens play an essential role in cell fate specification and patterning including in laying out the mammalian body plan during gastrulation. In vivo studies have shed light on the signaling pathways involved in this process and the phenotypes associated with their disruption, however, several important open questions remain regarding how morphogens function in space and time. Self-organized patterning systems based on embryonic stem cells have emerged as a powerful platform for beginning to address these questions that is complementary to in vivo approaches. Here we review recent progress in understanding morphogen signaling dynamics and patterning in early mammalian development by taking advantage of cutting-edge embryonic stem cell technology., (© 2020 Elsevier Inc. All rights reserved.)

Embryonic Stem cells are widely studied to elucidate the disease and developmental processes because of their capability to differentiate into cells of any lineage, Pervasive transcription is a distinct feature of all multicellular organisms and genomic elements such as enhancers and bidirectional or unidirectional promoters regulate these processes. Thousands of loci in each species produce a class of transcripts called noncoding RNAs (ncRNAs), that are well known for their influential regulatory roles in multiple biological processes including stem cell pluripotency and differentiation. The number of lncRNA species increases in more complex organisms highlighting the importance of RNA-based control in the evolution of multicellular organisms. Over the past decade, numerous studies have shed light on lncRNA biogenesis and functional significance in the cell and the organism. In this review, we focus primarily on lncRNAs affecting the stem cell state and developmental pathways., (© 2020 Elsevier Inc. All rights reserved.)

In eukaryotes, DNA is highly compacted within the nucleus into a structure known as chromatin. Modulation of chromatin structure allows for precise regulation of gene expression, and thereby controls cell fate decisions. Specific chromatin organization is established and preserved by numerous factors to generate desired cellular outcomes. In embryonic stem (ES) cells, chromatin is precisely regulated to preserve their two defining characteristics: self-renewal and pluripotent state. This action is accomplished by a litany of nucleosome remodelers, histone variants, epigenetic marks, and other chromatin regulatory factors. These highly dynamic regulatory factors come together to precisely define a chromatin state that is conducive to ES cell maintenance and development, where dysregulation threatens the survival and fitness of the developing organism., (© 2020 Elsevier Inc. All rights reserved.)

Organ-on-a-chip systems have the potential to revolutionize drug screening and disease modeling through the use of human stem cell-derived cardiomyocytes. The predictive power of these tissue models critically depends on the functional assembly and maturation of human cells that are used as building blocks for organ-on-a-chip systems. To resemble a more adult-like phenotype on these heart-on-a-chip systems, the surrounding micro-environment of individual cardiomyocyte needs to be controlled. Herein, we investigated the impact of four microenvironmental cues: cell seeding density, types and percentages of non-myocyte populations, the types of hydrogels used for tissue inoculation and the electrical conditioning regimes on the structural and functional assembly of human pluripotent stem cell-derived cardiac tissues. Utilizing a novel, plastic and open-access heart-on-a-chip system that is capable of continuous non-invasive monitoring of tissue contractions, we were able to study how different micro-environmental cues affect the assembly of the cardiomyocytes into a functional cardiac tissue. We have defined conditions that resulted in tissues exhibiting hallmarks of the mature human myocardium, such as positive force-frequency relationship and post-rest potentiation., (Copyright © 2019 International Society of Matrix Biology. Published by Elsevier B.V. All rights reserved.)

Embryonic stem cells have the capacities of self-renewal and pluripotency. Pluripotency establishment (somatic cell reprogramming), maintenance, and execution (differentiation) require orchestrated regulatory mechanisms of a cell's molecular machinery, including signaling pathways, epigenetics, transcription, translation, and protein degradation. RNA binding proteins (RBPs) take part in every process of RNA regulation and recent studies began to address their important functions in the regulation of pluripotency and reprogramming. Here, we discuss the roles of RBPs in key regulatory steps in the control of pluripotency and reprogramming. Among RNA binding proteins are a group of RNA helicases that are responsible for RNA structure remodeling with important functional implications. We highlight the largest family of RNA helicases, DDX (DEAD-box) helicase family and our current understanding of their functions specifically in the regulation of pluripotency and reprogramming., (© 2020 Elsevier Inc. All rights reserved.)

At least two distinct pluripotent states, referred to as naïve and primed, define the early mammalian embryo. In the mouse, the pluripotent epiblast cells in the pre/peri-implantation embryo are the source of naïve embryonic stem cells (ESCs). After the embryo implants, the epiblast lineage generates a restricted or primed population of stem cells, referred to as epiblast stem cells (EpiSCs). ESCs can be cultured in EpiSC media to generate epiblast-like cells (EpiLCs). The differentiation of naive ESCs into primed EpiLCs permits insights into the development and differentiation of the pluripotent epiblast lineage. This chapter describes the generation and characterization of EpiSCs as well as EpiLCs., (© 2020 Elsevier Inc. All rights reserved.)

Stem cell therapy using bone marrow derived or mesenchymal stem cells has become a popular option for cardiovascular disease treatment, however the administration of embryonic stem cells has been mostly experimental. Remarkably, most of these ongoing clinical trials involve adult patients, but little is known regarding the safety and efficacy of stem cell therapy in newborns and children battling congenital heart diseases. Furthermore, cell delivery methods involve the administration of stem cells without pre-differentiation, and without consideration for the consequent process of cardiac development. Interestingly, in-vitro studies have demonstrated that the differentiation of embryonic stem cells into cardiomyocytes imitates the stages of cardiogenesis. Wnt signaling plays a profound role during the earliest stages of cardiogenesis and cardiac differentiation. In fact inappropriate Wnt signaling is associated with numerous cardiac disorders especially congenital heart disease. Furthermore, cell-extracellular matrix interactions were shown to be critical for stem cell differentiation and adequate cardiogenesis. Since extracellular matrix molecules are fundamental for maintenance and repair during heart disease and congenital heart disease, they may offer a novel approach for therapy. Herein we aim to review the critical role of Wnt signaling, as well as the profound importance of cell extracellular matrix interaction, during cardiogenesis. Both of these processes are crucial for precise stem cell differentiation into cardiomyocytes and developing efficacious regenerative therapy for congenital heart disease., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Based on a previous finding that fusion of a somatic cell with an embryonic stem (ES) cell reprogrammed the somatic cell, genes for reprogramming transcription factors were selected and induced pluripotent stem (iPS) cell technology was developed. The cell fusion itself produced a tetraploid cell. To avoid nuclear fusion, a method for cytoplasmic fusion using a microtunnel device was developed. However, the ES cell was too small for cell pairing at the device. Therefore, in the present study, ES cell enlargement was carried out with the colchicine derivative demecolcine (DC). DC induced enlargement of ES cells without loss of their stemness. When an enlarged ES cell was paired with a somatic cell in the microtunnel device, cytoplasmic fusion was observed. The present method may be useful for further development of reprogramming techniques for iPS cell preparation without gene transfection., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Rett syndrome (RTT) is a childhood neurodevelopmental disorder caused by mutations in MECP2. To study the molecular mechanisms underlying RTT, four sublines of H1 hESCs were generated, carrying a hemizygous knockout or mutant allele of MECP2. Exons 3 and 4 of MECP2 were targeted using the CRISPR/Cas9 nuclease system., (Copyright © 2019 The Authors. Published by Elsevier B.V. All rights reserved.)

Induced pluripotent stem cells (iPSCs) show huge variations in their differentiation potential, even in the same condition. However, methods for predicting these differentiation tendencies, especially in the early stage of differentiation, are still scarce. This study aimed to establish a simple and practical system to predict the differentiation tendency of iPSC lines using embryoid bodies (EBs) with identified parameters in the early stage. We compared four human iPSC lines in terms of the morphology and maintenance of EBs and their gene expression levels of specific markers for three germ-layers. Furthermore, the differentiation potentials of these iPSC lines into melanocytes, which are ectoderm-derived cells, were also compared and correlated with the above parameters. The results showed that iPSC lines forming regular, smooth, and not cystic EBs, which could be maintained in culture for a relatively longer time, also expressed higher levels of ectoderm-specific markers and lower levels of mesoderm/endoderm markers. Additionally, these iPSC lines showed greater potential in melanocyte differentiation using EB-based protocol, and the induced melanocytes expressed melanocytic markers and presented characteristics that were similar to those of normal human melanocytes. By contrast, iPSC lines that formed cystic EBs with bright or dark cavities and expressed relatively lower levels of ectoderm-specific markers failed in the melanocyte differentiation. Collectively, the differentiation tendency of human iPSC lines may be predicted by specific parameters in the EB stage. The formation and maintenance of optimal EBs and the expression of germ layer-specific markers are particularly important and practical for the prediction assay in the early stage., (Copyright © 2019 Elsevier Inc. All rights reserved.)

The common marmoset (marmoset; Callithrix jacchus) shows anatomical and physiological features that are in common with humans. Establishing induced pluripotent stem cells (iPSCs) from marmosets holds promise for enhancing the utility of the animal model for biomedical and preclinical studies. However, in spite of the presence of some previous reports on marmoset iPSCs, the reprogramming technology in marmosets is still under development. In particular, the efficacy of RNA-based reprogramming has not been thoroughly investigated. In this study, we attempted RNA-based reprogramming for deriving iPSCs from marmoset fibroblasts. Although we failed to derive iPSC colonies from marmoset fibroblasts by using a conventional RNA-based reprogramming method previously validated in human fibroblasts, we succeeded in deriving colony-forming cells with a modified induction medium supplemented with a novel set of small molecules. Importantly, following one-week culture of the colony-forming cells in conventional embryonic stem cell (ESC) medium, we obtained iPSCs which express endogenous pluripotent markers and show a differentiation potential into all three germ layers. Taken together, our results indicate that RNA-based reprogramming, which is valuable for deriving transgene-free iPSCs, is applicable to marmosets., (Copyright © 2019 Elsevier Inc. All rights reserved.)

The differentiation of human induced pluripotent stem cells (hiPSCs) into osteoblasts provides a new paradigm in the field of bone tissue regeneration. The embryoid body (EB) differentiation method is commonly used for the osteogenic differentiation of hiPSCs. However, the spontaneous differentiation process of EBs is poorly understood, as evidenced by the inconsistency of the suspension time among previously reported studies as well as the low osteoblastic differentiation efficiency of hiPSCs. In the present study, we investigated the effects of the suspension culture time of EBs on the osteogenic differentiation of hiPSCs. Under chemically defined conditions, the expression of key genes related to presomitic mesoderm, neural crest, mesenchymal and pre-osteoblast cells in EBs derived from hiPSCs was examined daily by quantitative RT-PCR. Then, EBs with varying times in suspension (3, 5, 7 or 10 days) were attached onto gelatine surfaces, and their osteoblastic differentiation efficiencies after 14 days of culture in osteogenic induction medium were determined. Our results showed that EBs derived from hiPSCs subjected to 4 days of suspension culture produced the most mesenchymal stem cells, and exhibited the best osteogenic differentiation efficiency. Our research is valuable to standardizing, the time in suspension for the osteogenic differentiation of hiPSCs through the EB method, and facilitated the development of a high-efficiency in vitro osteogenic differentiation system for hiPSCs., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Pituitary homeobox 3 (Pitx3) is a key transcription factor that plays an important role in the development and maintenance of midbrain dopaminergic (mDA) neurons. Here, we established a PITX3-mCherry knock-in reporter human embryonic stem cell (hESC) line using the CRISPR/Cas9 system. PITX3-mCherry hESCs maintained pluripotency marker expression and exhibited the capacity to generate all 3 germ layers and a normal karyotype. After differentiation into mDA neurons, most PITX3 immunoreactivity overlapped with the red fluorescence of mCherry. This reporter cell line may be used to study the development of mDA neurons or to enrich mDA populations for transplantation., (Copyright © 2019 The Authors. Published by Elsevier B.V. All rights reserved.)

Caudal-type homeobox 2 (.Cdx2) transcription factor is an essential regulator of differentiation to the intestinal epithelium, somatic mesoderm and trophectoderm function in the mouse. However, the regulation of Cdx2 in these processes is poorly understood. Separation of viable Cdx2 expressing cells during differentiation for downstream experiments is not possible due to its nuclear localization, limiting experimental possibilities and studying Cdx2 regulation. Here, we report generation of a Cdx2-mCherry knock-in reporter mouse embryonic stem cell line (TCMC), for modeling and studying in vitro differentiation of mESCs to intestinal epithelia, somatic mesoderm, and trophectoderm., (Copyright © 2019. Published by Elsevier B.V.)

Neural crest cells are a multipotent embryonic stem cell population that migrate large distances to contribute a variety of tissues. The cranial neural crest, which contribute to tissues of the face and skull, undergo collective migration whose movement has been likened to cancer metastasis. Over the last few years, a variety of mechanisms for the guidance of collective cranial neural crest cell migration have been described: mostly chemical, but more recently mechanical. Here we review these different mechanisms and attempt to integrate them to provide a unified model of collective cranial neural crest cell migration., (Copyright © 2019 The Authors. Published by Elsevier Ltd.. All rights reserved.)

TRIM28 (also known as KAP1 or TIF1β) is the universal co-repressor of the Krüppel-associated box-containing zinc finger proteins (Krab-ZFPs), the largest family of transcription factors in mammals. During early embryogenesis, TRIM28 mediates the transcriptional silencing of many endogenous retroviral elements and genomic imprinted sites. Silencing is initiated by the recruitment of TRIM28 to a target locus by members of the Krab-ZFP. Subsequently, TRIM28 functions as a scaffold protein to recruit chromatin modifying effectors featuring SETDB1, HP1 and the NuRD complex. Although many protein partners involved in silencing have been identified, the molecular basis of the protein interactions that mediate silencing remains largely unclear. In the present study, we identified the first Bbox domain (T28_B1 135-203) as a molecular interface responsible for the formation of higher-order oligomers of TRIM28. The structure of this domain reveals a new interface on the surface of the Bbox domain. Mutants disrupting the interface disrupt the formation of oligomers but have no observed effect on transcriptional silencing defining a single TRIM28 dimer as the functional unit for silencing. Using assembly-deficient mutants, we employed small-angle X-ray scattering and biophysical techniques to characterize binding to member of the Krab-ZFP family. This allows us to narrow and define the binding interface to the center of the coiled-coil region (residues 294-321) of TRIM28 and define mutants that abolish binding to the Krab-ZFP proteins., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Stem cell-based approaches have the potential to address the organ shortage in transplantation. Whereas both embryonic stem cells and induced pluripotent stem cells have been utilized as cellular sources for differentiation and lineage specification, their relative ability to be recognized by immune effector cells is unclear. We determined the expression of immune recognition molecules on hepatocyte-like cells (HLC) generated from murine embryonic stem cells and induced pluripotent stem cells, compared to adult hepatocytes, and we evaluated the impact on recognition by natural killer (NK) cells. We report that HLC lack MHC class I expression, and that embryonic stem cell-derived HLC have higher expression of the NK cell activating ligands Rae1, H60, and Mult1 than induced pluripotent stem cell-derived HLC and adult hepatocytes. Moreover, the lack of MHC class I renders embryonic stem cell-derived HLC, and induced pluripotent stem cell-derived HLC, susceptible to killing by syngeneic and allogeneic NK cells. Both embryonic stem cell-derived HLC, and induced pluripotent stem cell-derived HLC, are killed by NK cells at higher levels than adult hepatocytes. Finally, we demonstrate that the NK cell activation receptor, NKG2D, plays a key role in NK cell cytotoxicity of embryonic stem cell-derived HLC, but not induced pluripotent stem cell-derived HLC., (© 2018 The American Society of Transplantation and the American Society of Transplant Surgeons.)

The protein activator of protein kinase R (PKR) (PACT) is known to play important roles in PKR regulation and microRNA biogenesis. Based on the observation that PACT is specifically expressed in the ventricular zone (VZ) at the mid-neurogenic period, we examine the role of PACT in this embryonic neural stem cell niche. Here, we provide the first evidence that PACT increases neurosphere formation, as well as expression of Notch target genes and the neural stem cell marker Sox2 in primary neural stem cells in vitro. Consistently, introduction of PACT into the mouse embryonic brain in utero increased the fraction of cells localizing to the VZ. We also show that the PACT-enhanced stemness of neural stem cells is PKR-independent. At the molecular level, PACT was revealed to physically interact with C promoter binding factor 1 (CBF1) and dramatically strengthen the association between CBF1 and Notch intracellular domain (NICD), which indicates stabilization of the Notch transcriptional coactivation complex responsible for Notch target gene expression. Taken together, our study indicates that PACT is a novel transcriptional coactivator of the Notch pathway playing a pivotal role during mammalian brain development., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Cynomolgus monkey ES (Cyn ES) cells can be generated in a similar manner as human ES cells. However, Cyn ES cells are difficult to maintain in an undifferentiated state by untrained researchers. For easier culture, we generated an OCT3/4-P2A tdTomato IRES Zeocin R Cyn ES cell line using CRISPR/Cas9 genome editing technology. The stop codon of the endogenous OCT3/4 locus was replaced with the P2A tdTomato IRES Zeocin R pA cassette by homologous recombination. This cell line enables us to isolate pluripotent stem cells and exclude differentiated cells by addition of zeocin, especially for culture without feeder cells., (Copyright © 2019 The Authors. Published by Elsevier B.V. All rights reserved.)

Human pluripotent stem cells (hPSCs) acquire changes at the genomic level upon proliferation and differentiation (Peterson and Loring, 2014). Studies from International Stem Cell Initiative and independent laboratories identified a copy number variant (CNV) in hES cell lines displaying a normal karyotype, which provided a selective advantage to hES cells in culture. In our laboratory we have identified variant H9-hESC (derived from H9-hESC) with normal karyotype, pluripotency expression, differentiation profile but with altered traits of high cell survival and low E-CADHERIN expression., (Copyright © 2019 The Authors. Published by Elsevier B.V. All rights reserved.)

Reduced levels of TERC , the telomerase RNA component, cause dyskeratosis congenita (DC) in patients harboring mutations in TERC, PARN, NOP10, NHP2, NAF1, or DKC1. Inhibition of the noncanonical poly(A) polymerase PAPD5 , or the exosome RNA degradation complex, partially restores TERC levels in immortalized DKC1 mutant cells, but it remains unknown if modulation of posttranscriptional processing of TERC could improve hematopoietic output in DC. We used human embryonic stem cells (hESCs) with a common dyskerin mutation (DKC1_A353V), which have defective telomere maintenance and reduced definitive hematopoietic potential, to understand the effects of reducing EXOSC3 activity, or silencing PAPD5-mediated oligoadenylation, on hematopoietic progenitor specification and function in DC. Reduction of EXOSC3 or PAPD5 levels in DKC1 mutant hESCs led to functional improvements in TERC levels and telomerase activity, with concomitant telomere elongation and reduced levels of DNA damage signaling. Interestingly, the silencing of PAPD5 , but not EXOSC3 , significantly restored definitive hematopoietic potential in DKC1 mutant cells. Mechanistically, we show that PAPD5 inhibition is sustained in differentiated CD34 + cells, with a concomitant increase in mature, functional, forms of TERC , indicating that regulation of PAPD5 is a potential strategy to reverse hematologic dysfunction in DC patients., (© 2019 by The American Society of Hematology.)

Chromatin remodeling is fundamental for the dynamical changes in transcriptional programs that occur during development and stem cell differentiation. The histone acetyltransferase Kat6b is relevant for neurogenesis in mouse embryos, and mutations of this gene cause intellectual disability in humans. However, the molecular mechanisms involved in Kat6b mutant phenotype and the role of this chromatin modifier in embryonic stem (ES) cells remain elusive. In this work, we show that Kat6b is expressed in ES cells and is repressed during differentiation. Moreover, we found that this gene is regulated by the pluripotency transcription factors Nanog and Oct4. To study the functional relevance of Kat6b in ES cells, we generated a Kat6b knockout ES cell line (K6b-/-) using CRISPR/Cas9. Fluorescence correlation spectroscopy analyses suggest a more compact chromatin organization in K6b-/- cells and impaired interactions of Oct4 and Nanog with chromatin. Remarkably, K6b-/- cells showed a reduced efficiency to differentiate to neural lineage. These results reveal a role of Kat6b as a modulator of chromatin plasticity, its impact on chromatin-transcription factors interactions and its influence on cell fate decisions during neural development., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Cystic fibrosis transmembrane conductance regulator (CFTR) is a transmembrane Cl - and HCO 3 - transporter and its malfunction leads to cystic fibrosis (CF) and multiple congenital diseases. The most common mutation in CF patient is DF508 and the patients have increased risk in developing gastrointestinal tumors. To explore the etiology of high cancer risk in DF508-CF patients, we have derived mouse DF508-CFTR embryonic stem (ES) cells and use it as a novel in vitro model to study the role of CFTR from developmental angle. We found the self-renewal properties are intact in DF508-CFTR ES cells. Nevertheless, the differentiation of intestine lineage, the expression of intestine progenitor and major intestine differentiated cell markers is significantly upregulated in DF508-CFTR ES cell differentiated cells. Therefore, CFTR plays an important role in intestine lineage differentiation. Besides, DF508-CFTR ES cells formed teratomas demonstrated enhanced expressions of cell proliferation, migration and epithelial-mesenchymal transition associated marker genes, indicating the tumor suppressive role of CFTR. Taken together, our derived DF508-CFTR ES cells can serve as a new model to study the etiology of CF disease in vitro and malignant teratoma formation in vivo., (Copyright © 2019 Elsevier Inc. All rights reserved.)