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1.
J Vis Exp ; (207)2024 May 17.
Article En | MEDLINE | ID: mdl-38829111

The human enteric nervous system, ENS, is a large network of glial and neuronal cell types with remarkable neurotransmitter diversity. The ENS controls bowel motility, enzyme secretion, and nutrient absorption and interacts with the immune system and the gut microbiome. Consequently, developmental and acquired defects of the ENS are responsible for many human diseases and may contribute to symptoms of Parkinson's disease. Limitations in animal model systems and access to primary tissue pose significant experimental challenges in studies of the human ENS. Here, a detailed protocol is presented for effective in vitro derivation of the ENS lineages from human pluripotent stem cells, hPSC, using defined culture conditions. Our protocol begins with directed differentiation of hPSCs to enteric neural crest cells within 15 days and yields diverse subtypes of functional enteric neurons within 30 days. This platform provides a scalable resource for developmental studies, disease modeling, drug discovery, and regenerative applications.


Cell Differentiation , Enteric Nervous System , Neural Crest , Pluripotent Stem Cells , Humans , Enteric Nervous System/cytology , Pluripotent Stem Cells/cytology , Cell Differentiation/physiology , Neural Crest/cytology , Cytological Techniques/methods , Neurons/cytology
2.
Stem Cell Res Ther ; 15(1): 130, 2024 May 03.
Article En | MEDLINE | ID: mdl-38702837

BACKGROUND: Hyaluronan (HA) is an extracellular glycosaminoglycan polysaccharide with widespread roles throughout development and in healthy and neoplastic tissues. In pluripotent stem cell culture it can support both stem cell renewal and differentiation. However, responses to HA in culture are influenced by interaction with a range of cognate factors and receptors including components of blood serum supplements, which alter results. These may contribute to variation in cell batch production yield and phenotype as well as heighten the risks of adventitious pathogen transmission in the course of cell processing for therapeutic applications. MAIN: Here we characterise differentiation of a human embryo/pluripotent stem cell derived Mesenchymal Stromal Cell (hESC/PSC-MSC)-like cell population by culture on a planar surface coated with HA in serum-free media qualified for cell production for therapy. Resulting cells met minimum criteria of the International Society for Cellular Therapy for identification as MSC by expression of. CD90, CD73, CD105, and lack of expression for CD34, CD45, CD14 and HLA-II. They were positive for other MSC associated markers (i.e.CD166, CD56, CD44, HLA 1-A) whilst negative for others (e.g. CD271, CD71, CD146). In vitro co-culture assessment of MSC associated functionality confirmed support of growth of hematopoietic progenitors and inhibition of mitogen activated proliferation of lymphocytes from umbilical cord and adult peripheral blood mononuclear cells, respectively. Co-culture with immortalized THP-1 monocyte derived macrophages (Mɸ) concurrently stimulated with lipopolysaccharide as a pro-inflammatory stimulus, resulted in a dose dependent increase in pro-inflammatory IL6 but negligible effect on TNFα. To further investigate these functionalities, a bulk cell RNA sequence comparison with adult human bone marrow derived MSC and hESC substantiated a distinctive genetic signature more proximate to the former. CONCLUSION: Cultivation of human pluripotent stem cells on a planar substrate of HA in serum-free culture media systems is sufficient to yield a distinctive developmental mesenchymal stromal cell lineage with potential to modify the function of haematopoietic lineages in therapeutic applications.


Cell Differentiation , Hyaluronic Acid , Mesenchymal Stem Cells , Pluripotent Stem Cells , Humans , Mesenchymal Stem Cells/metabolism , Mesenchymal Stem Cells/cytology , Hyaluronic Acid/pharmacology , Hyaluronic Acid/metabolism , Pluripotent Stem Cells/metabolism , Pluripotent Stem Cells/cytology , Culture Media, Serum-Free/pharmacology , Cell Lineage , Cells, Cultured , Cell Culture Techniques/methods , Coculture Techniques
3.
Dev Cell ; 59(9): 1093-1095, 2024 May 06.
Article En | MEDLINE | ID: mdl-38714156

In this issue of Developmental Cell, Fowler et al. applied genetic lineage-tracing mouse models to support the notion that artery endothelial cells are the predominant source of hematopoietic stem cells. They leveraged this and developed a method capable of efficiently differentiating human pluripotent stem cells into HLF+HOXA+ hematopoietic progenitors.


Cell Differentiation , Hematopoiesis , Hematopoietic Stem Cells , Pluripotent Stem Cells , Hematopoietic Stem Cells/cytology , Hematopoietic Stem Cells/metabolism , Animals , Humans , Pluripotent Stem Cells/cytology , Pluripotent Stem Cells/metabolism , Mice , Cell Lineage , Endothelial Cells/cytology , Endothelial Cells/metabolism
4.
Int J Mol Sci ; 25(9)2024 Apr 29.
Article En | MEDLINE | ID: mdl-38732061

Embryonic stem-like cells (ES-like cells) are promising for medical research and clinical applications. Traditional methods involve "Yamanaka" transcription (OSKM) to derive these cells from somatic cells in vitro. Recently, a novel approach has emerged, obtaining ES-like cells from spermatogonia stem cells (SSCs) in a time-related process without adding artificial additives to cell cultures, like transcription factors or small molecules such as pten or p53 inhibitors. This study aims to investigate the role of the Nanog in the conversion of SSCs to pluripotent stem cells through both in silico analysis and in vitro experiments. We used bioinformatic methods and microarray data to find significant genes connected to this derivation path, to construct PPI networks, using enrichment analysis, and to construct miRNA-lncRNA networks, as well as in vitro experiments, immunostaining, and Fluidigm qPCR analysis to connect the dots of Nanog significance. We concluded that Nanog is one of the most crucial differentially expressed genes during SSC conversion, collaborating with critical regulators such as Sox2, Dazl, Pou5f1, Dnmt3, and Cdh1. This intricate protein network positions Nanog as a pivotal factor in pathway enrichment for generating ES-like cells, including Wnt signaling, focal adhesion, and PI3K-Akt-mTOR signaling. Nanog expression is presumed to play a vital role in deriving ES-like cells from SSCs in vitro. Finding its pivotal role in this path illuminates future research and clinical applications.


Nanog Homeobox Protein , Nanog Homeobox Protein/metabolism , Nanog Homeobox Protein/genetics , Animals , Male , Embryonic Stem Cells/metabolism , Embryonic Stem Cells/cytology , Cell Differentiation , Mice , MicroRNAs/genetics , MicroRNAs/metabolism , Spermatogonia/cytology , Spermatogonia/metabolism , Computer Simulation , Gene Regulatory Networks , RNA, Long Noncoding/genetics , RNA, Long Noncoding/metabolism , Pluripotent Stem Cells/metabolism , Pluripotent Stem Cells/cytology , Gene Expression Profiling , Computational Biology/methods , Humans
5.
Cell Rep ; 43(5): 114219, 2024 May 28.
Article En | MEDLINE | ID: mdl-38748874

Defining the molecular networks orchestrating human brain formation is crucial for understanding neurodevelopment and neurological disorders. Challenges in acquiring early brain tissue have incentivized the use of three-dimensional human pluripotent stem cell (hPSC)-derived neural organoids to recapitulate neurodevelopment. To elucidate the molecular programs that drive this highly dynamic process, here, we generate a comprehensive trans-omic map of the phosphoproteome, proteome, and transcriptome of the exit of pluripotency and neural differentiation toward human cerebral organoids (hCOs). These data reveal key phospho-signaling events and their convergence on transcriptional factors to regulate hCO formation. Comparative analysis with developing human and mouse embryos demonstrates the fidelity of our hCOs in modeling embryonic brain development. Finally, we demonstrate that biochemical modulation of AKT signaling can control hCO differentiation. Together, our data provide a comprehensive resource to study molecular controls in human embryonic brain development and provide a guide for the future development of hCO differentiation protocols.


Brain , Cell Differentiation , Organoids , Humans , Organoids/metabolism , Brain/metabolism , Brain/embryology , Animals , Mice , Pluripotent Stem Cells/metabolism , Pluripotent Stem Cells/cytology , Proteome/metabolism , Signal Transduction , Transcriptome/genetics , Proteomics/methods , Neurogenesis , Proto-Oncogene Proteins c-akt/metabolism
6.
Cell Rep ; 43(5): 114232, 2024 May 28.
Article En | MEDLINE | ID: mdl-38761378

The advent of novel 2D and 3D models for human development, including trophoblast stem cells and blastoids, has expanded opportunities for investigating early developmental events, gradually illuminating the enigmatic realm of human development. While these innovations have ushered in new prospects, it has become essential to establish well-defined benchmarks for the cell sources of these models. We aimed to propose a comprehensive characterization of pluripotent and trophoblastic stem cell models by employing a combination of transcriptomic, proteomic, epigenetic, and metabolic approaches. Our findings reveal that extended pluripotent stem cells share many characteristics with primed pluripotent stem cells, with the exception of metabolic activity. Furthermore, our research demonstrates that DNA hypomethylation and high metabolic activity define trophoblast stem cells. These results underscore the necessity of considering multiple hallmarks of pluripotency rather than relying on a single criterion. Multiplying hallmarks alleviate stage-matching bias.


Trophoblasts , Humans , Trophoblasts/metabolism , Trophoblasts/cytology , DNA Methylation , Pluripotent Stem Cells/metabolism , Pluripotent Stem Cells/cytology , Models, Biological , Embryo Implantation , Cell Differentiation , Epigenesis, Genetic , Transcriptome/genetics , Proteomics/methods
7.
Genome Biol ; 25(1): 122, 2024 May 13.
Article En | MEDLINE | ID: mdl-38741214

BACKGROUND: Pluripotent states of embryonic stem cells (ESCs) with distinct transcriptional profiles affect ESC differentiative capacity and therapeutic potential. Although single-cell RNA sequencing has revealed additional subpopulations and specific features of naive and primed human pluripotent stem cells (hPSCs), the underlying mechanisms that regulate their specific transcription and that control their pluripotent states remain elusive. RESULTS: By single-cell analysis of high-resolution, three-dimensional (3D) genomic structure, we herein demonstrate that remodeling of genomic structure is highly associated with the pluripotent states of human ESCs (hESCs). The naive pluripotent state is featured with specialized 3D genomic structures and clear chromatin compartmentalization that is distinct from the primed state. The naive pluripotent state is achieved by remodeling the active euchromatin compartment and reducing chromatin interactions at the nuclear center. This unique genomic organization is linked to enhanced chromatin accessibility on enhancers and elevated expression levels of naive pluripotent genes localized to this region. In contradistinction, the primed state exhibits intermingled genomic organization. Moreover, active euchromatin and primed pluripotent genes are distributed at the nuclear periphery, while repressive heterochromatin is densely concentrated at the nuclear center, reducing chromatin accessibility and the transcription of naive genes. CONCLUSIONS: Our data provide insights into the chromatin structure of ESCs in their naive and primed states, and we identify specific patterns of modifications in transcription and chromatin structure that might explain the genes that are differentially expressed between naive and primed hESCs. Thus, the inversion or relocation of heterochromatin to euchromatin via compartmentalization is related to the regulation of chromatin accessibility, thereby defining pluripotent states and cellular identity.


Pluripotent Stem Cells , Single-Cell Analysis , Humans , Pluripotent Stem Cells/metabolism , Pluripotent Stem Cells/cytology , Genome, Human , Euchromatin/genetics , Euchromatin/metabolism , Chromatin/metabolism , Human Embryonic Stem Cells/metabolism , Human Embryonic Stem Cells/cytology , Heterochromatin/metabolism , Embryonic Stem Cells/metabolism , Chromatin Assembly and Disassembly
8.
Stem Cell Res Ther ; 15(1): 139, 2024 May 12.
Article En | MEDLINE | ID: mdl-38735988

The concept of "stemness" incorporates the molecular mechanisms that regulate the unlimited self-regenerative potential typical of undifferentiated primitive cells. These cells possess the unique ability to navigate the cell cycle, transitioning in and out of the quiescent G0 phase, and hold the capacity to generate diverse cell phenotypes. Stem cells, as undifferentiated precursors endow with extraordinary regenerative capabilities, exhibit a heterogeneous and tissue-specific distribution throughout the human body. The identification and characterization of distinct stem cell populations across various tissues have revolutionized our understanding of tissue homeostasis and regeneration. From the hematopoietic to the nervous and musculoskeletal systems, the presence of tissue-specific stem cells underlines the complex adaptability of multicellular organisms. Recent investigations have revealed a diverse cohort of non-hematopoietic stem cells (non-HSC), primarily within bone marrow and other stromal tissue, alongside established hematopoietic stem cells (HSC). Among these non-HSC, a rare subset exhibits pluripotent characteristics. In vitro and in vivo studies have demonstrated the remarkable differentiation potential of these putative stem cells, known by various names including multipotent adult progenitor cells (MAPC), marrow-isolated adult multilineage inducible cells (MIAMI), small blood stem cells (SBSC), very small embryonic-like stem cells (VSELs), and multilineage differentiating stress enduring cells (MUSE). The diverse nomenclatures assigned to these primitive stem cell populations may arise from different origins or varied experimental methodologies. This review aims to present a comprehensive comparison of various subpopulations of multipotent/pluripotent stem cells derived from stromal tissues. By analysing isolation techniques and surface marker expression associated with these populations, we aim to delineate the similarities and distinctions among stromal tissue-derived stem cells. Understanding the nuances of these tissue-specific stem cells is critical for unlocking their therapeutic potential and advancing regenerative medicine. The future of stem cells research should prioritize the standardization of methodologies and collaborative investigations in shared laboratory environments. This approach could mitigate variability in research outcomes and foster scientific partnerships to fully exploit the therapeutic potential of pluripotent stem cells.


Multipotent Stem Cells , Pluripotent Stem Cells , Humans , Pluripotent Stem Cells/cytology , Pluripotent Stem Cells/metabolism , Multipotent Stem Cells/cytology , Multipotent Stem Cells/metabolism , Cell Differentiation , Stromal Cells/cytology , Stromal Cells/metabolism , Animals
9.
Nat Commun ; 15(1): 3931, 2024 May 10.
Article En | MEDLINE | ID: mdl-38729993

MYC plays various roles in pluripotent stem cells, including the promotion of somatic cell reprogramming to pluripotency, the regulation of cell competition and the control of embryonic diapause. However, how Myc expression is regulated in this context remains unknown. The Myc gene lies within a ~ 3-megabase gene desert with multiple cis-regulatory elements. Here we use genomic rearrangements, transgenesis and targeted mutation to analyse Myc regulation in early mouse embryos and pluripotent stem cells. We identify a topologically-associated region that homes enhancers dedicated to Myc transcriptional regulation in stem cells of the pre-implantation and early post-implantation embryo. Within this region, we identify elements exclusively dedicated to Myc regulation in pluripotent cells, with distinct enhancers that sequentially activate during naive and formative pluripotency. Deletion of pluripotency-specific enhancers dampens embryonic stem cell competitive ability. These results identify a topologically defined enhancer cluster dedicated to early embryonic expression and uncover a modular mechanism for the regulation of Myc expression in different states of pluripotency.


Enhancer Elements, Genetic , Gene Expression Regulation, Developmental , Pluripotent Stem Cells , Proto-Oncogene Proteins c-myc , Animals , Mice , Proto-Oncogene Proteins c-myc/metabolism , Proto-Oncogene Proteins c-myc/genetics , Pluripotent Stem Cells/metabolism , Pluripotent Stem Cells/cytology , Transcription, Genetic , Embryo, Mammalian/metabolism , Embryonic Stem Cells/metabolism , Female , Male
10.
Expert Rev Endocrinol Metab ; 19(3): 217-227, 2024 May.
Article En | MEDLINE | ID: mdl-38693782

INTRODUCTION: Type 1 diabetes (T1D) mellitus is an autoimmune disease in which immune cells, predominantly effector T cells, destroy insulin-secreting beta-cells. Beta-cell destruction led to various consequences ranging from retinopathy and nephropathy to neuropathy. Different strategies have been developed to achieve normoglycemia, including exogenous glucose compensation, whole pancreas transplantation, islet transplantation, and beta-cell replacement. AREAS COVERED: The last two decades of experience have shown that indigenous glucose compensation through beta-cell regeneration and protection is a peerless method for T1D therapy. Tremendous studies have tried to find an unlimited source for beta-cell regeneration, on the one hand, and beta-cell protection against immune attack, on the other hand. Recent advances in stem cell technology, gene editing methods, and immune modulation approaches provide a unique opportunity for both beta-cell regeneration and protection. EXPERT OPINION: Pluripotent stem cell differentiation into the beta-cell is considered an unlimited source for beta-cell regeneration. Devising engineered pancreas-specific regulatory T cells using Chimeric Antigen Receptor (CAR) technology potentiates an effective immune tolerance induction for beta-cell protection. Beta-cell regeneration using pluripotent stem cells and beta-cell protection using pancreas-specific engineered regulatory T cells promises to develop a curative protocol in T1D.


Diabetes Mellitus, Type 1 , Insulin-Secreting Cells , Islets of Langerhans Transplantation , Regeneration , Humans , Diabetes Mellitus, Type 1/therapy , Diabetes Mellitus, Type 1/immunology , Insulin-Secreting Cells/physiology , Islets of Langerhans Transplantation/methods , Animals , Pluripotent Stem Cells , Pancreas Transplantation/methods
11.
Nat Genet ; 56(5): 758-766, 2024 May.
Article En | MEDLINE | ID: mdl-38741017

Human pluripotent stem (hPS) cells can, in theory, be differentiated into any cell type, making them a powerful in vitro model for human biology. Recent technological advances have facilitated large-scale hPS cell studies that allow investigation of the genetic regulation of molecular phenotypes and their contribution to high-order phenotypes such as human disease. Integrating hPS cells with single-cell sequencing makes identifying context-dependent genetic effects during cell development or upon experimental manipulation possible. Here we discuss how the intersection of stem cell biology, population genetics and cellular genomics can help resolve the functional consequences of human genetic variation. We examine the critical challenges of integrating these fields and approaches to scaling them cost-effectively and practically. We highlight two areas of human biology that can particularly benefit from population-scale hPS cell studies, elucidating mechanisms underlying complex disease risk loci and evaluating relationships between common genetic variation and pharmacotherapeutic phenotypes.


Genetics, Population , Genomics , Humans , Genomics/methods , Pluripotent Stem Cells , Genetic Variation , Phenotype , Single-Cell Analysis/methods , Disease/genetics
12.
Stem Cell Reports ; 19(5): 710-728, 2024 May 14.
Article En | MEDLINE | ID: mdl-38701780

Heterogeneity among both primed and naive pluripotent stem cell lines remains a major unresolved problem. Here we show that expressing the maternal-specific linker histone H1FOO fused to a destabilizing domain (H1FOO-DD), together with OCT4, SOX2, KLF4, and LMYC, in human somatic cells improves the quality of reprogramming to both primed and naive pluripotency. H1FOO-DD expression was associated with altered chromatin accessibility around pluripotency genes and with suppression of the innate immune response. Notably, H1FOO-DD generates naive induced pluripotent stem cells with lower variation in transcriptome and methylome among clones and a more uniform and superior differentiation potency. Furthermore, we elucidated that upregulation of FKBP1A, driven by these five factors, plays a key role in H1FOO-DD-mediated reprogramming.


Cellular Reprogramming , Histones , Induced Pluripotent Stem Cells , Kruppel-Like Factor 4 , Cellular Reprogramming/genetics , Humans , Induced Pluripotent Stem Cells/cytology , Induced Pluripotent Stem Cells/metabolism , Histones/metabolism , Cell Differentiation/genetics , Kruppel-Like Transcription Factors/metabolism , Kruppel-Like Transcription Factors/genetics , SOXB1 Transcription Factors/metabolism , SOXB1 Transcription Factors/genetics , Chromatin/metabolism , Pluripotent Stem Cells/metabolism , Pluripotent Stem Cells/cytology , Transcription Factors/metabolism , Transcription Factors/genetics , Transcriptome
13.
Sci Rep ; 14(1): 10420, 2024 05 07.
Article En | MEDLINE | ID: mdl-38710730

In the mouse embryo, the transition from the preimplantation to the postimplantation epiblast is governed by changes in the gene regulatory network (GRN) that lead to transcriptional, epigenetic, and functional changes. This transition can be faithfully recapitulated in vitro by the differentiation of mouse embryonic stem cells (mESCs) to epiblast-like cells (EpiLCs), that reside in naïve and formative states of pluripotency, respectively. However, the GRN that drives this conversion is not fully elucidated. Here we demonstrate that the transcription factor OCT6 is a key driver of this process. Firstly, we show that Oct6 is not expressed in mESCs but is rapidly induced as cells exit the naïve pluripotent state. By deleting Oct6 in mESCs, we find that knockout cells fail to acquire the typical morphological changes associated with the formative state when induced to differentiate. Additionally, the key naïve pluripotency TFs Nanog, Klf2, Nr5a2, Prdm14, and Esrrb were expressed at higher levels than in wild-type cells, indicating an incomplete dismantling of the naïve pluripotency GRN. Conversely, premature expression of Oct6 in naïve cells triggered a rapid morphological transformation mirroring differentiation, that was accompanied by the upregulation of the endogenous Oct6 as well as the formative genes Sox3, Zic2/3, Foxp1, Dnmt3A and FGF5. Strikingly, we found that OCT6 represses Nanog in a bistable manner and that this regulation is at the transcriptional level. Moreover, our findings also reveal that Oct6 is repressed by NANOG. Collectively, our results establish OCT6 as a key TF in the dissolution of the naïve pluripotent state and support a model where Oct6 and Nanog form a double negative feedback loop which could act as an important toggle mediating the transition to the formative state.


Cell Differentiation , Gene Regulatory Networks , Mouse Embryonic Stem Cells , Nanog Homeobox Protein , Animals , Mice , Nanog Homeobox Protein/metabolism , Nanog Homeobox Protein/genetics , Cell Differentiation/genetics , Mouse Embryonic Stem Cells/metabolism , Mouse Embryonic Stem Cells/cytology , Pluripotent Stem Cells/metabolism , Pluripotent Stem Cells/cytology , Gene Expression Regulation, Developmental , Octamer Transcription Factor-3/metabolism , Octamer Transcription Factor-3/genetics , Germ Layers/metabolism , Germ Layers/cytology , Mice, Knockout
14.
Theriogenology ; 225: 67-80, 2024 Sep 01.
Article En | MEDLINE | ID: mdl-38795512

Here, we examined the effects of the BMP signaling pathway inhibitor LDN-193189 on the pluripotency of porcine embryonic stem cells (ESCs) in the absence of feeder cells using molecular and transcriptomic techniques. Additionally, the effects of some extracellular matrix components on porcine ESC pluripotency were evaluated to develop an optimized and sustainable feeder-free culture system for porcine ESCs. Feeder cells were found to play an important role in supporting the pluripotency of porcine ESCs by blocking trophoblast and mesodermal differentiation through the inhibition of the BMP pathway. Additionally, treatment with LDN-193189, an inhibitor of the BMP pathway, maintained the pluripotency and homogeneity of porcine ESCs for an extended period in the absence of feeder cells by stimulating the secretion of chemokines and suppressing differentiation, based on transcriptome analysis. Conclusively, these results suggest that LDN-193189 could be a suitable replacement for feeder cells in the maintenance of porcine ESC pluripotency during culture. Additionally, these findings contribute to the understanding of pluripotency gene networks and comparative embryogenesis.


Embryonic Stem Cells , Pyrazoles , Signal Transduction , Animals , Swine , Embryonic Stem Cells/drug effects , Signal Transduction/drug effects , Pyrazoles/pharmacology , Pyrimidines/pharmacology , Bone Morphogenetic Proteins/metabolism , Pluripotent Stem Cells/drug effects , Cell Differentiation/drug effects , Smad Proteins/metabolism , Smad Proteins/genetics , Feeder Cells , Cell Culture Techniques
15.
Cell Mol Life Sci ; 81(1): 210, 2024 May 08.
Article En | MEDLINE | ID: mdl-38717553

The cytoophidium is an evolutionarily conserved subcellular structure formed by filamentous polymers of metabolic enzymes. In vertebrates, inosine monophosphate dehydrogenase (IMPDH), which catalyses the rate-limiting step in guanosine triphosphate (GTP) biosynthesis, is one of the best-known cytoophidium-forming enzymes. Formation of the cytoophidium has been proposed to alleviate the inhibition of IMPDH, thereby facilitating GTP production to support the rapid proliferation of certain cell types such as lymphocytes, cancer cells and pluripotent stem cells (PSCs). However, past studies lacked appropriate models to elucidate the significance of IMPDH cytoophidium under normal physiological conditions. In this study, we demonstrate that the presence of IMPDH cytoophidium in mouse PSCs correlates with their metabolic status rather than pluripotency. By introducing IMPDH2 Y12C point mutation through genome editing, we established mouse embryonic stem cell (ESC) lines incapable of forming IMPDH polymers and the cytoophidium. Our data indicate an important role of IMPDH cytoophidium in sustaining a positive feedback loop that couples nucleotide biosynthesis with upstream metabolic pathways. Additionally, we find that IMPDH2 Y12C mutation leads to decreased cell proliferation and increased DNA damage in teratomas, as well as impaired embryo development following blastocoel injection. Further analysis shows that IMPDH cytoophidium assembly in mouse embryonic development begins after implantation and gradually increases throughout fetal development. These findings provide insights into the regulation of IMPDH polymerisation in embryogenesis and its significance in coordinating cell metabolism and development.


Cell Proliferation , IMP Dehydrogenase , Animals , Female , Mice , DNA Damage , Fetal Development/genetics , Guanosine Triphosphate/metabolism , IMP Dehydrogenase/metabolism , IMP Dehydrogenase/genetics , Mice, Inbred C57BL , Pluripotent Stem Cells/metabolism , Pluripotent Stem Cells/cytology , Cellular Structures/metabolism
16.
Genome Res ; 34(4): 572-589, 2024 May 15.
Article En | MEDLINE | ID: mdl-38719471

Dormancy is a key feature of stem cell function in adult tissues as well as in embryonic cells in the context of diapause. The establishment of dormancy is an active process that involves extensive transcriptional, epigenetic, and metabolic rewiring. How these processes are coordinated to successfully transition cells to the resting dormant state remains unclear. Here we show that microRNA activity, which is otherwise dispensable for preimplantation development, is essential for the adaptation of early mouse embryos to the dormant state of diapause. In particular, the pluripotent epiblast depends on miRNA activity, the absence of which results in the loss of pluripotent cells. Through the integration of high-sensitivity small RNA expression profiling of individual embryos and protein expression of miRNA targets with public data of protein-protein interactions, we constructed the miRNA-mediated regulatory network of mouse early embryos specific to diapause. We find that individual miRNAs contribute to the combinatorial regulation by the network, and the perturbation of the network compromises embryo survival in diapause. We further identified the nutrient-sensitive transcription factor TFE3 as an upstream regulator of diapause-specific miRNAs, linking cytoplasmic MTOR activity to nuclear miRNA biogenesis. Our results place miRNAs as a critical regulatory layer for the molecular rewiring of early embryos to establish dormancy.


Cell Proliferation , MicroRNAs , Pluripotent Stem Cells , Animals , MicroRNAs/genetics , MicroRNAs/metabolism , Mice , Pluripotent Stem Cells/metabolism , Pluripotent Stem Cells/cytology , Gene Expression Regulation, Developmental , Gene Regulatory Networks , Embryonic Development/genetics , Germ Layers/metabolism , Germ Layers/cytology , Blastocyst/metabolism , Blastocyst/cytology , Female
17.
Proc Natl Acad Sci U S A ; 121(22): e2316176121, 2024 May 28.
Article En | MEDLINE | ID: mdl-38771878

The striato-nigral (Str-SN) circuit is composed of medium spiny neuronal projections that are mainly sent from the striatum to the midbrain substantial nigra (SN), which is essential for regulating motor behaviors. Dysfunction of the Str-SN circuitry may cause a series of motor disabilities that are associated with neurodegenerative disorders, such as Huntington's disease (HD). Although the etiology of HD is known as abnormally expanded CAG repeats of the huntingtin gene, treatment of HD remains tremendously challenging. One possible reason is the lack of effective HD model that resembles Str-SN circuitry deficits for pharmacological studies. Here, we first differentiated striatum-like organoids from human pluripotent stem cells (hPSCs), containing functional medium spiny neurons (MSNs). We then generated 3D Str-SN assembloids by assembling striatum-like organoids with midbrain SN-like organoids. With AAV-hSYN-GFP-mediated viral tracing, extensive MSN projections from the striatum to the SN are established, which formed synaptic connection with GABAergic neurons in SN organoids and showed the optically evoked inhibitory postsynaptic currents and electronic field potentials by labeling the striatum-like organoids with optogenetic virus. Furthermore, these Str-SN assembloids exhibited enhanced calcium activity compared to that of individual striatal organoids. Importantly, we further demonstrated the reciprocal projection defects in HD iPSC-derived assembloids, which could be ameliorated by treatment of brain-derived neurotrophic factor. Taken together, these findings suggest that Str-SN assembloids could be used for identifying MSN projection defects and could be applied as potential drug test platforms for HD.


Huntington Disease , Organoids , Humans , Huntington Disease/pathology , Huntington Disease/metabolism , Organoids/pathology , Organoids/metabolism , Substantia Nigra/pathology , Substantia Nigra/metabolism , Corpus Striatum/pathology , Corpus Striatum/metabolism , Neurons/metabolism , Neurons/pathology , Cell Differentiation , GABAergic Neurons/metabolism , GABAergic Neurons/pathology , Pluripotent Stem Cells/metabolism , Optogenetics
18.
Cell Stem Cell ; 31(5): 583-585, 2024 May 02.
Article En | MEDLINE | ID: mdl-38701751

How nuclear RNA homeostasis impacts cellular functions remains elusive. In this issue of Cell Stem Cell, Han et al.1 utilized a controllable protein degradation system targeting EXOSC2 to perturb RNA homeostasis in mouse pluripotent embryonic stem cells, revealing its vital role in orchestrating crucial nuclear events for cellular fitness.


Homeostasis , RNA, Nuclear , Animals , Mice , RNA, Nuclear/metabolism , RNA, Nuclear/genetics , Exosome Multienzyme Ribonuclease Complex/metabolism , Exosome Multienzyme Ribonuclease Complex/genetics , Cell Nucleus/metabolism , Mouse Embryonic Stem Cells/metabolism , Mouse Embryonic Stem Cells/cytology , Humans , RNA-Binding Proteins/metabolism , RNA-Binding Proteins/genetics , RNA/metabolism , Pluripotent Stem Cells/metabolism , Pluripotent Stem Cells/cytology
19.
Signal Transduct Target Ther ; 9(1): 86, 2024 Apr 08.
Article En | MEDLINE | ID: mdl-38584163

During spaceflight, the cardiovascular system undergoes remarkable adaptation to microgravity and faces the risk of cardiac remodeling. Therefore, the effects and mechanisms of microgravity on cardiac morphology, physiology, metabolism, and cellular biology need to be further investigated. Since China started constructing the China Space Station (CSS) in 2021, we have taken advantage of the Shenzhou-13 capsule to send human pluripotent stem cell-derived cardiomyocytes (hPSC-CMs) to the Tianhe core module of the CSS. In this study, hPSC-CMs subjected to space microgravity showed decreased beating rate and abnormal intracellular calcium cycling. Metabolomic and transcriptomic analyses revealed a battery of metabolic remodeling of hPSC-CMs in spaceflight, especially thiamine metabolism. The microgravity condition blocked the thiamine intake in hPSC-CMs. The decline of thiamine utilization under microgravity or by its antagonistic analog amprolium affected the process of the tricarboxylic acid cycle. It decreased ATP production, which led to cytoskeletal remodeling and calcium homeostasis imbalance in hPSC-CMs. More importantly, in vitro and in vivo studies suggest that thiamine supplementation could reverse the adaptive changes induced by simulated microgravity. This study represents the first astrobiological study on the China Space Station and lays a solid foundation for further aerospace biomedical research. These data indicate that intervention of thiamine-modified metabolic reprogramming in human cardiomyocytes during spaceflight might be a feasible countermeasure against microgravity.


Pluripotent Stem Cells , Weightlessness , Humans , Metabolic Reprogramming , Myocytes, Cardiac/metabolism , Calcium/metabolism , Cell Differentiation , Pluripotent Stem Cells/metabolism
20.
Stem Cell Res Ther ; 15(1): 118, 2024 Apr 24.
Article En | MEDLINE | ID: mdl-38659053

BACKGROUND: Cerebral organoids (COs) are the most advanced in vitro models that resemble the human brain. The use of COs as a model for Alzheimer's disease (AD), as well as other brain diseases, has recently gained attention. This study aimed to develop a human AD CO model using normal human pluripotent stem cells (hPSCs) that recapitulates the pathological phenotypes of AD and to determine the usefulness of this model for drug screening. METHODS: We established AD hPSC lines from normal hPSCs by introducing genes that harbor familial AD mutations, and the COs were generated using these hPSC lines. The pathological features of AD, including extensive amyloid-ß (Aß) accumulation, tauopathy, and neurodegeneration, were analyzed using enzyme-linked immunosorbent assay, Amylo-Glo staining, thioflavin-S staining, immunohistochemistry, Bielschowsky's staining, and western blot analysis. RESULTS: The AD COs exhibited extensive Aß accumulation. The levels of paired helical filament tau and neurofibrillary tangle-like silver deposits were highly increased in the AD COs. The number of cells immunoreactive for cleaved caspase-3 was significantly increased in the AD COs. In addition, treatment of AD COs with BACE1 inhibitor IV, a ß-secretase inhibitor, and compound E, a γ-secretase inhibitor, significantly attenuated the AD pathological features. CONCLUSION: Our model effectively recapitulates AD pathology. Hence, it is a valuable platform for understanding the mechanisms underlying AD pathogenesis and can be used to test the efficacy of anti-AD drugs.


Alzheimer Disease , Amyloid beta-Peptides , Organoids , Pluripotent Stem Cells , Humans , Alzheimer Disease/metabolism , Alzheimer Disease/pathology , Alzheimer Disease/genetics , Organoids/metabolism , Organoids/pathology , Pluripotent Stem Cells/metabolism , Amyloid beta-Peptides/metabolism , Amyloid beta-Peptides/genetics , Amyloid Precursor Protein Secretases/metabolism , Amyloid Precursor Protein Secretases/genetics , Amyloid Precursor Protein Secretases/antagonists & inhibitors , tau Proteins/metabolism , tau Proteins/genetics , Aspartic Acid Endopeptidases/metabolism , Aspartic Acid Endopeptidases/genetics , Brain/metabolism , Brain/pathology , Models, Biological
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