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1.
Genes Dev ; 34(7-8): 598-618, 2020 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-32115407

RESUMEN

Gastrulation in the early postimplantation stage mammalian embryo begins when epiblast cells ingress to form the primitive streak or develop as the embryonic ectoderm. The DNA dioxygenase Tet1 is highly expressed in the epiblast and yet continues to regulate lineage specification during gastrulation when its expression is diminished. Here, we show how Tet1 plays a pivotal role upstream of germ layer lineage bifurcation. During the transition from naive pluripotency to lineage priming, a global reconfiguration redistributes Tet1 from Oct4-cobound promoters to distal regulatory elements at lineage differentiation genes, which are distinct from high-affinity sites engaged by Oct4. An altered chromatin landscape in Tet1-deficient primed epiblast-like cells is associated with enhanced Oct4 expression and binding to Nodal and Wnt target genes, resulting in collaborative signals that enhance mesendodermal and inhibit neuroectodermal gene expression during lineage segregation. A permissive role for Tet1 in neural fate induction involves Zic2-dependent engagement at neural target genes at lineage priming, is dependent on the signaling environment during gastrulation, and impacts neural tube closure after gastrulation. Our findings provide mechanistic information for epigenetic integration of pluripotency and signal-induced differentiation cues.


Asunto(s)
Diferenciación Celular/genética , Linaje de la Célula/genética , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Células Madre Pluripotentes/citología , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas/metabolismo , Animales , Células Cultivadas , Cromatina/metabolismo , Embrión de Mamíferos , Eliminación de Gen , Regulación del Desarrollo de la Expresión Génica , Estratos Germinativos/metabolismo , Ratones , Factor 3 de Transcripción de Unión a Octámeros/metabolismo , Transducción de Señal/genética , Factores de Transcripción/metabolismo
2.
Org Biomol Chem ; 20(7): 1493-1499, 2022 02 16.
Artículo en Inglés | MEDLINE | ID: mdl-35107115

RESUMEN

Few methods are known for the synthesis of nitroindole derivatives. A simple and practical Cs2CO3-promoted method for the synthesis of 6-nitroindole derivatives from enaminones and nitroaromatic compounds has been developed. Two new C-C and C-N bonds were formed in a highly regioselective manner under transition metal-free conditions.

3.
Org Biomol Chem ; 19(10): 2277-2283, 2021 03 18.
Artículo en Inglés | MEDLINE | ID: mdl-33624664

RESUMEN

A three-component [3 + 2 + 1] annulation strategy for the synthesis of biologically and pharmaceutically active 2,3-diarylpyridine derivatives by using a series of allylic alcohols, ketones, and ammonium acetate as substrates has been developed. The method proceeds efficiently under metal-free conditions, and the desired heterocycles could be obtained in a site-specific selectivity manner with good functional group tolerance.

4.
J Virol ; 92(13)2018 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-29643244

RESUMEN

Human immunodeficiency virus type 1 (HIV-1) can infect nondividing cells via passing through the nuclear pore complex. The nuclear membrane-imbedded protein SUN2 was recently reported to be involved in the nuclear import of HIV-1. Whether SUN1, which shares many functional similarities with SUN2, is involved in this process remained to be explored. Here we report that overexpression of SUN1 specifically inhibited infection by HIV-1 but not that by simian immunodeficiency virus (SIV) or murine leukemia virus (MLV). Overexpression of SUN1 did not affect reverse transcription but led to reduced accumulation of the 2-long-terminal-repeat (2-LTR) circular DNA and integrated viral DNA, suggesting a block in the process of nuclear import. HIV-1 CA was mapped as a determinant for viral sensitivity to SUN1. Treatment of SUN1-expressing cells with cyclosporine (CsA) significantly reduced the sensitivity of the virus to SUN1, and an HIV-1 mutant containing CA-G89A, which does not interact with cyclophilin A (CypA), was resistant to SUN1 overexpression. Downregulation of endogenous SUN1 inhibited the nuclear entry of the wild-type virus but not that of the G89A mutant. These results indicate that SUN1 participates in the HIV-1 nuclear entry process in a manner dependent on the interaction of CA with CypA.IMPORTANCE HIV-1 infects both dividing and nondividing cells. The viral preintegration complex (PIC) can enter the nucleus through the nuclear pore complex. It has been well known that the viral protein CA plays an important role in determining the pathways by which the PIC enters the nucleus. In addition, the interaction between CA and the cellular protein CypA has been reported to be important in the selection of nuclear entry pathways, though the underlying mechanisms are not very clear. Here we show that both SUN1 overexpression and downregulation inhibited HIV-1 nuclear entry. CA played an important role in determining the sensitivity of the virus to SUN1: the regulatory activity of SUN1 toward HIV-1 relied on the interaction between CA and CypA. These results help to explain how SUN1 is involved in the HIV-1 nuclear entry process.


Asunto(s)
Cápside/metabolismo , Núcleo Celular/metabolismo , Ciclofilina A/metabolismo , Infecciones por VIH/virología , VIH-1/patogenicidad , Proteínas de la Membrana/metabolismo , Proteínas Asociadas a Microtúbulos/metabolismo , Proteínas Nucleares/metabolismo , Transporte Activo de Núcleo Celular , Células HeLa , Humanos , Integración Viral
5.
Biochem Biophys Res Commun ; 443(3): 1048-53, 2014 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-24365151

RESUMEN

SRG3 plays essential roles both in early mouse embryogenesis and in extra-embryonic vascular development. As one of the core components of the SWI/SNF-like BAF complex, SRG3 serves as the scaffold protein and its protein level controls the stability of the BAF complex, which controls diverse physiological processes through transcriptional regulation. However, little is known about how the protein level of SRG3 is regulated in mammalian cells. Previously, we identified a murine ubiquitin ligase (Wwp2) and demonstrated that it interacts with pluripotency-associated key transcription factor Oct4 and RNA polymerase II large subunit Rpb1, promoting their ubiquitination and degradation. Here, we report that Wwp2 acts as a ubiquitin ligase of SRG3. Our results show that Wwp2 and SRG3 form protein complexes and co-localize in the nucleus in mammalian cells. The interaction is mediated through the WW domain of Wwp2 and the PPPY motif of SRG3, respectively. Importantly, Wwp2 promotes ubiquitination and degradation of SRG3 through the ubiquitin-proteasome system. The expression of a catalytically inactive mutant of Wwp2 abolishes SRG3 ubiquitination. Collectively, our study opens up a new avenue to understand how the protein level of SRG3 is regulated in mammalian cells.


Asunto(s)
Complejos Multiproteicos/metabolismo , Proteolisis , Factores de Transcripción/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitinación , Animales , Proteínas Cromosómicas no Histona , Células HEK293 , Humanos , Mamíferos/metabolismo , Ratones , Unión Proteica
6.
Health Inf Sci Syst ; 12(1): 21, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38464463

RESUMEN

Cancer is a complex gene mutation disease that derives from the accumulation of mutations during somatic cell evolution. With the advent of high-throughput technology, a large amount of omics data has been generated, and how to find cancer-related driver genes from a large number of omics data is a challenge. In the early stage, the researchers developed many frequency-based driver genes identification methods, but they could not identify driver genes with low mutation rates well. Afterwards, researchers developed network-based methods by fusing multi-omics data, but they rarely considered the connection among features. In this paper, after analyzing a large number of methods for integrating multi-omics data, a hierarchical weak consensus model for fusing multiple features is proposed according to the connection among features. By analyzing the connection between PPI network and co-mutation hypergraph network, this paper firstly proposes a new topological feature, called co-mutation clustering coefficient (CMCC). Then, a hierarchical weak consensus model is used to integrate CMCC, mRNA and miRNA differential expression scores, and a new driver genes identification method HWC is proposed. In this paper, the HWC method and current 7 state-of-the-art methods are compared on three types of cancers. The comparison results show that HWC has the best identification performance in statistical evaluation index, functional consistency and the partial area under ROC curve. Supplementary Information: The online version contains supplementary material available at 10.1007/s13755-024-00279-6.

7.
bioRxiv ; 2024 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-38370615

RESUMEN

Facultative heterochromatinization of genomic regulators by Polycomb repressive complex (PRC) 1 and 2 is essential in development and differentiation; however, the underlying molecular mechanisms remain obscure. Using genetic engineering, molecular approaches, and live-cell single-molecule imaging, we quantify the number of proteins within condensates formed through liquid-liquid phase separation (LLPS) and find that in mouse embryonic stem cells (mESCs), approximately 3 CBX2 proteins nucleate many PRC1 and PRC2 subunits to form one non-stoichiometric condensate. We demonstrate that sparse CBX2 prevents Polycomb proteins from migrating to constitutive heterochromatin, demarcates the spatial boundaries of facultative heterochromatin, controls the deposition of H3K27me3, regulates transcription, and impacts cellular differentiation. Furthermore, we show that LLPS of CBX2 is required for the demarcation and deposition of H3K27me3 and is essential for cellular differentiation. Our findings uncover new functional roles of LLPS in the formation of facultative heterochromatin and unravel a new mechanism by which low-abundant proteins nucleate many other proteins to form compartments that enable them to execute their functions.

8.
Methods Mol Biol ; 2618: 133-145, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36905514

RESUMEN

Dendritic cells (DCs) represent one of the most important immune cell subsets in preventing the host from pathogen invasion by promoting both innate and adaptive immunity. Most research on human dendritic cells has focused on the easy-to-obtain dendritic cells derived in vitro from monocytes (MoDCs). However, many questions remain unanswered regarding the role of different dendritic cell types. The investigation of their roles in human immunity is hampered by their rarity and fragility, which especially holds true for type 1 conventional dendritic cells (cDC1s) and for plasmacytoid dendritic cells (pDCs). In vitro differentiation from hematopoietic progenitors emerged as a common way to produce different DC types, but the efficiency and reproducibility of these protocols needed to be improved and the extent to which the DCs generated in vitro resembled their in vivo counterparts required a more rigorous and global assessment. Here, we describe a cost-effective and robust in vitro differentiation system for the production of cDC1s and pDCs equivalent to their blood counterparts, from cord blood CD34+ hematopoietic stem cells (HSCs) cultured on a stromal feeder layer with a combination of cytokines and growth factors.


Asunto(s)
Células Dendríticas , Células Madre Hematopoyéticas , Humanos , Reproducibilidad de los Resultados , Diferenciación Celular , Antígenos CD34/metabolismo
9.
Health Inf Sci Syst ; 11(1): 55, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37981988

RESUMEN

Essential proteins play a vital role in development and reproduction of cells. The identification of essential proteins helps to understand the basic survival of cells. Due to time-consuming, costly and inefficient with biological experimental methods for discovering essential proteins, computational methods have gained increasing attention. In the initial stage, essential proteins are mainly identified by the centralities based on protein-protein interaction (PPI) networks, which limit their identification rate due to many false positives in PPI networks. In this study, a purified PPI network is firstly introduced to reduce the impact of false positives in the PPI network. Secondly, by analyzing the similarity relationship between a protein and its neighbors in the PPI network, a new centrality called neighborhood similarity centrality (NSC) is proposed. Thirdly, based on the subcellular localization and orthologous data, the protein subcellular localization score and ortholog score are calculated, respectively. Fourthly, by analyzing a large number of methods based on multi-feature fusion, it is found that there is a special relationship among features, which is called dominance relationship, then, a novel model based on dominance relationship is proposed. Finally, NSC, subcellular localization score, and ortholog score are fused by the dominance relationship model, and a new method called NSO is proposed. In order to verify the performance of NSO, the seven representative methods (ION, NCCO, E_POC, SON, JDC, PeC, WDC) are compared on yeast datasets. The experimental results show that the NSO method has higher identification rate than other methods.

10.
Genome Biol ; 23(1): 122, 2022 05 30.
Artículo en Inglés | MEDLINE | ID: mdl-35637459

RESUMEN

DNA methylation plays vital roles in both prokaryotes and eukaryotes. There are three forms of DNA methylation in prokaryotes: N6-methyladenine (6mA), N4-methylcytosine (4mC), and 5-methylcytosine (5mC). Although many sequencing methods have been developed to sequence specific types of methylation, few technologies can be used for efficiently mapping multiple types of methylation. Here, we present NT-seq for mapping all three types of methylation simultaneously. NT-seq reliably detects all known methylation motifs in two bacterial genomes and can be used for identifying de novo methylation motifs. NT-seq provides a simple and efficient solution for detecting multiple types of DNA methylation.


Asunto(s)
5-Metilcitosina , Epigenoma , Metilación de ADN , Genoma Bacteriano , Genómica
11.
Math Biosci Eng ; 19(9): 9168-9199, 2022 06 22.
Artículo en Inglés | MEDLINE | ID: mdl-35942754

RESUMEN

This study aimed to develop a 5G + "mixed computing" + deep learning-based next-generation intelligent health-monitoring platform for an ethylene cracking furnace tube based on 5G communication technology, with the goal of improving the health management level of the key component of ethylene production, that is, the cracking furnace tube, and focusing on the key common technical difficulties of ethylene production of tube outer-surface temperature sensing and tube slagging diagnosis. It also integrated the edge-fog-cloud "mixed computing" technology and deep learning technology in artificial intelligence, which had a higher degree in the research and development of automation and intelligence, and was more versatile in an industrial environment. The platform included a 5G-based tube intelligent temperature-measuring device, a 5G-based intelligent peep door gearing, a 5G-based edge-fog-cloud collaboration mechanism, and a mixed deep learning-related application. The platform enhanced the automation and intelligence of the enterprise, which could not only promote the quality and efficiency of the enterprise but also protect the safe operation of the cracking furnace device and lead the technological progress and transformation and upgrading of the industry through the application.


Asunto(s)
Inteligencia Artificial , Inteligencia , Automatización , Etilenos
12.
RSC Adv ; 11(49): 30937-30942, 2021 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-35498930

RESUMEN

A straightforward aerobic oxidative esterification of aryl aldehydes with alcohols has been developed for the synthesis of substituted esters by employing vitamin B1 as a cost-effective, metal-free, and eco-friendly NHC catalyst. Air is used as a green terminal oxidant. The reaction is a useful addition to the existing NHC-catalytic oxidative esterification.

13.
Protein Cell ; 12(10): 756-768, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34405377

RESUMEN

N6-methyladenine (N6-mA, m6dA, or 6mA), a prevalent DNA modification in prokaryotes, has recently been identified in higher eukaryotes, including mammals. Although 6mA has been well-studied in prokaryotes, the function and regulatory mechanism of 6mA in eukaryotes are still poorly understood. Recent studies indicate that 6mA can serve as an epigenetic mark and play critical roles in various biological processes, from transposable-element suppression to environmental stress response. Here, we review the significant advances in methodology for 6mA detection and major progress in understanding the regulation and function of this non-canonical DNA methylation in eukaryotes, predominantly mammals.


Asunto(s)
Adenina/análogos & derivados , Reparación del ADN , ADN/metabolismo , Epigénesis Genética , Genoma , Adenina/metabolismo , Aminopirina N-Demetilasa/genética , Aminopirina N-Demetilasa/metabolismo , Animales , Cromatografía Líquida de Alta Presión , ADN/genética , Metilación de ADN , Metilasas de Modificación del ADN/genética , Metilasas de Modificación del ADN/metabolismo , Regulación de la Expresión Génica , Heterocromatina/química , Heterocromatina/metabolismo , Humanos , Immunoblotting , Mamíferos , Espectrometría de Masas
14.
Mol Immunol ; 123: 40-59, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32413788

RESUMEN

Dendritic cells (DCs) are mononuclear phagocytes that are specialized in the induction and functional polarization of effector lymphocytes, thus orchestrating immune defenses against infections and cancer. The population of DC encompasses distinct cell types that vary in their efficacy for complementary functions and are thus likely involved in defending the body against different threats. Plasmacytoid DCs specialize in the production of high levels of the antiviral cytokines type I interferons. Type 1 conventional DCs (cDC1s) excel in the activation of cytotoxic CD8+ T cells (CTLs) which are critical for defense against cancer and infections by intracellular pathogens. Type 2 conventional DCs (cDC2s) prime helper CD4+ T cells for the production of type 2 cytokines underpinning immune defenses against worms or of IL-17 promoting control of infections by extracellular bacteria or fungi. Hence, clinically manipulating the development and functions of DC types could have a major impact for improving treatments against many diseases. However, the rarity and fragility of human DC types is impeding advancement towards this goal. To overcome this roadblock, major efforts are ongoing to generate in vitro large numbers of distinct human DC types. We review here the current state of this research field, emphasizing recent breakthrough and proposing future priorities. We also pinpoint the necessity to develop a consensus nomenclature and rigorous methodologies to ensure proper identification and characterization of human DC types. Finally, we elaborate on how faithful in vitro models of human DC types can accelerate our understanding of the biology of these cells and the engineering of next generation vaccines or immunotherapies against viral infections or cancer.


Asunto(s)
Células Dendríticas/citología , Células Dendríticas/fisiología , Modelos Teóricos , Animales , Presentación de Antígeno/fisiología , Linfocitos T CD8-positivos/inmunología , Citocinas/metabolismo , Células Dendríticas/patología , Humanos , Activación de Linfocitos , Reproducibilidad de los Resultados
15.
Cell Rep ; 30(7): 2150-2169.e9, 2020 02 18.
Artículo en Inglés | MEDLINE | ID: mdl-32075734

RESUMEN

Reprogramming somatic cells into induced pluripotent stem cells (iPSCs) involves the reactivation of endogenous pluripotency genes and global DNA demethylation, but temporal resolution of these events using existing markers is limited. Here, we generate murine transgenic lines harboring reporters for the 5-methylcytosine dioxygenase Tet1 and for Oct4. By monitoring dual reporter fluorescence during pluripotency entry, we identify a sequential order of Tet1 and Oct4 activation by proximal and distal regulatory elements. Full Tet1 activation marks an intermediate stage that accompanies predominantly repression of somatic genes, preceding full Oct4 activation, and distinguishes two waves of global DNA demethylation that target distinct genomic features but are uncoupled from transcriptional changes. Tet1 knockout shows that TET1 contributes to both waves of demethylation and activates germline regulatory genes in reprogramming intermediates but is dispensable for Oct4 reactivation. Our dual reporter system for time-resolving pluripotency entry thus refines the molecular roadmap of iPSC maturation.


Asunto(s)
Desmetilación del ADN , Proteínas de Unión al ADN/metabolismo , Células Madre Pluripotentes Inducidas/metabolismo , Factor 3 de Transcripción de Unión a Octámeros/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Animales , Reprogramación Celular , Proteínas de Unión al ADN/genética , Epigenómica , Femenino , Genómica , Células Madre Pluripotentes Inducidas/citología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Factor 3 de Transcripción de Unión a Octámeros/genética , Embarazo , Proteínas Proto-Oncogénicas/genética , Transcriptoma
16.
Nat Cell Biol ; 21(8): 1041-1051, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31371824

RESUMEN

Endometrial disorders represent a major gynaecological burden. Current research models fail to recapitulate the nature and heterogeneity of these diseases, thereby hampering scientific and clinical progress. Here we developed long-term expandable organoids from a broad spectrum of endometrial pathologies. Organoids from endometriosis show disease-associated traits and cancer-linked mutations. Endometrial cancer-derived organoids accurately capture cancer subtypes, replicate the mutational landscape of the tumours and display patient-specific drug responses. Organoids were also established from precancerous pathologies encompassing endometrial hyperplasia and Lynch syndrome, and inherited gene mutations were maintained. Endometrial disease organoids reproduced the original lesion when transplanted in vivo. In summary, we developed multiple organoid models that capture endometrial disease diversity and will provide powerful research models and drug screening and discovery tools.


Asunto(s)
Evaluación Preclínica de Medicamentos , Neoplasias Endometriales/patología , Organoides/patología , Enfermedades Uterinas/patología , Técnicas de Cultivo de Célula/métodos , Evaluación Preclínica de Medicamentos/métodos , Neoplasias Endometriales/tratamiento farmacológico , Neoplasias Endometriales/metabolismo , Endometrio/patología , Femenino , Humanos , Organoides/efectos de los fármacos , Organoides/metabolismo , Enfermedades Uterinas/tratamiento farmacológico , Enfermedades Uterinas/metabolismo
17.
Cell Death Dis ; 9(9): 924, 2018 09 11.
Artículo en Inglés | MEDLINE | ID: mdl-30206204

RESUMEN

Trophoblast lineages, precursors of the placenta, are essential for post-implantation embryo survival. However, the regulatory network of trophoblast development remains incompletely understood. Here, we report that Cited1, a transcription coactivator, is a robust inducer for trophoblast-like state from mouse embryonic stem cells (ESCs). Depletion of Cited1 in ESCs compromises the trophoblast lineage specification induced by BMP signaling. In contrast, overexpression of Cited1 in ESCs induces a trophoblast-like state with elevated expression of trophoblast marker genes in vitro and generation of trophoblastic tumors in vivo. Furthermore, global transcriptome profile analysis indicates that ectopic Cited1 activates a trophoblast-like transcriptional program in ESCs. Mechanistically, Cited1 interacts with Bmpr2 and Smad4 to activate the Cited1-Bmpr2-Smad1/5/8 axis in the cytoplasm and Cited1-Smad4-p300 complexes in the nucleus, respectively. Collectively, our results show that Cited1 plays an important role in regulating trophoblast lineage specification through activating the BMP signaling pathway.


Asunto(s)
Proteína Morfogenética Ósea 1/metabolismo , Regulación del Desarrollo de la Expresión Génica/genética , Células Madre Embrionarias de Ratones/citología , Proteínas Nucleares/metabolismo , Transactivadores/metabolismo , Trofoblastos/citología , Animales , Proteínas Reguladoras de la Apoptosis , Receptores de Proteínas Morfogenéticas Óseas de Tipo II/metabolismo , Línea Celular , Proteína p300 Asociada a E1A/metabolismo , Femenino , Ratones , Proteínas Nucleares/genética , Placenta/embriología , Embarazo , Transducción de Señal , Proteína Smad4/metabolismo , Transactivadores/genética , Transcripción Genética/genética
18.
Nat Genet ; 49(7): 1061-1072, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28504700

RESUMEN

The mammalian TET enzymes catalyze DNA demethylation. While they have been intensely studied as major epigenetic regulators, little is known about their physiological roles and the extent of functional redundancy following embryo implantation. Here we define non-redundant roles for TET1 at an early postimplantation stage of the mouse embryo, when its paralogs Tet2 and Tet3 are not detectably expressed. TET1 regulates numerous genes defining differentiation programs in the epiblast and extraembryonic ectoderm. In epiblast cells, TET1 demethylates gene promoters via hydroxymethylation and maintains telomere stability. Surprisingly, TET1 represses a majority of epiblast target genes independently of methylation changes, in part through regulation of the gene encoding the transcriptional repressor JMJD8. Dysregulated gene expression in the absence of TET1 causes embryonic defects, which are partially penetrant in an inbred strain but fully lethal in non-inbred mice. Collectively, our study highlights an interplay between the catalytic and non-catalytic activities of TET1 that is essential for normal development.


Asunto(s)
Proteínas de Unión al ADN/fisiología , Desarrollo Embrionario/genética , Proteínas Proto-Oncogénicas/fisiología , Animales , Encéfalo/embriología , Encéfalo/metabolismo , Catálisis , Linaje de la Célula , Cruzamientos Genéticos , Metilación de ADN/fisiología , Proteínas de Unión al ADN/deficiencia , Proteínas de Unión al ADN/genética , Ectodermo/metabolismo , Gástrula/metabolismo , Dosificación de Gen , Regulación del Desarrollo de la Expresión Génica/genética , Técnicas de Inactivación de Genes , Estratos Germinativos/metabolismo , Edad Gestacional , Histona Demetilasas con Dominio de Jumonji/biosíntesis , Histona Demetilasas con Dominio de Jumonji/genética , Ratones , Ratones Endogámicos C57BL , Células Madre Pluripotentes/metabolismo , Proteínas Proto-Oncogénicas/deficiencia , Proteínas Proto-Oncogénicas/genética , Eliminación de Secuencia , Homeostasis del Telómero/fisiología
19.
Stem Cell Res Ther ; 7(1): 79, 2016 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-27236334

RESUMEN

BACKGROUND: Intrinsic factors and extrinsic signals which control unlimited self-renewal and developmental pluripotency in embryonic stem cells (ESCs) have been extensively investigated. However, a much smaller number of factors involved in extra-embryonic trophoblast differentiation from ESCs have been studied. In this study, we investigated the role of the single-stranded DNA binding protein, Ssbp3, for the induction of trophoblast-like differentiation from mouse ESCs. METHODS: Gain- and loss-of-function experiments were carried out through overexpression or knockdown of Ssbp3 in mouse ESCs under self-renewal culture conditions. Expression levels of pluripotency and lineage markers were detected by real-time quantitative reverse-transcription polymerase chain reaction (qRT-PCR) analyses. The global gene expression profile in Ssbp3-overexpressing cells was determined by affymetrix microarray. Gene ontology and pathway terms were analyzed and further validated by qRT-PCR and Western blotting. The methylation status of the Elf5 promoter in Ssbp3-overexpressing cells was detected by bisulfite sequencing. The trophoblast-like phenotype induced by Ssbp3 was also evaluated by teratoma formation and early embryo injection assays. RESULTS: Forced expression of Ssbp3 in mouse ESCs upregulated expression levels of lineage-associated genes, with trophoblast cell markers being the highest. In contrast, depletion of Ssbp3 attenuated the expression of trophoblast lineage marker genes induced by downregulation of Oct4 or treatment with BMP4 and bFGF in ESCs. Interestingly, global gene expression profiling analysis indicated that Ssbp3 overexpression did not significantly alter the transcript levels of pluripotency-associated transcription factors. Instead, Ssbp3 promoted the expression of early trophectoderm transcription factors such as Cdx2 and activated MAPK/Erk1/2 and TGF-ß pathways. Furthermore, overexpression of Ssbp3 reduced the methylation level of the Elf5 promoter and promoted the generation of teratomas with internal hemorrhage, indicative of the presence of trophoblast cells. CONCLUSIONS: This study identifies Ssbp3, a single-stranded DNA binding protein, as a regulator for mouse ESCs to differentiate into trophoblast-like cells. This finding is helpful to understand the regulatory networks for ESC differentiation into extra-embryonic lineages.


Asunto(s)
ADN de Cadena Simple/metabolismo , Proteínas de Unión al ADN/metabolismo , Células Madre Embrionarias de Ratones/metabolismo , Trofoblastos/metabolismo , Animales , Proteína Morfogenética Ósea 4/farmacología , Factor de Transcripción CDX2/genética , Factor de Transcripción CDX2/metabolismo , Diferenciación Celular , ADN de Cadena Simple/genética , Proteínas de Unión al ADN/genética , Embrión de Mamíferos , Factor 2 de Crecimiento de Fibroblastos/farmacología , Perfilación de la Expresión Génica , Regulación del Desarrollo de la Expresión Génica , Ratones , Análisis por Micromatrices , Quinasas de Proteína Quinasa Activadas por Mitógenos/genética , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Células Madre Embrionarias de Ratones/citología , Células Madre Embrionarias de Ratones/efectos de los fármacos , Factor 3 de Transcripción de Unión a Octámeros/genética , Factor 3 de Transcripción de Unión a Octámeros/metabolismo , Regiones Promotoras Genéticas , Unión Proteica , Transducción de Señal , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Factor de Crecimiento Transformador beta/genética , Factor de Crecimiento Transformador beta/metabolismo , Trofoblastos/citología , Trofoblastos/efectos de los fármacos
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