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Sample records for mouse embryonic neocortex

  1. DGCR8 Promotes Neural Progenitor Expansion and Represses Neurogenesis in the Mouse Embryonic Neocortex

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    Nadin Hoffmann

    2018-04-01

    Full Text Available DGCR8 and DROSHA are the minimal functional core of the Microprocessor complex essential for biogenesis of canonical microRNAs and for the processing of other RNAs. Conditional deletion of Dgcr8 and Drosha in the murine telencephalon indicated that these proteins exert crucial functions in corticogenesis. The identification of mechanisms of DGCR8- or DROSHA-dependent regulation of gene expression in conditional knockout mice are often complicated by massive apoptosis. Here, to investigate DGCR8 functions on amplification/differentiation of neural progenitors cells (NPCs in corticogenesis, we overexpress Dgcr8 in the mouse telencephalon, by in utero electroporation (IUEp. We find that DGCR8 promotes the expansion of NPC pools and represses neurogenesis, in absence of apoptosis, thus overcoming the usual limitations of Dgcr8 knockout-based approach. Interestingly, DGCR8 selectively promotes basal progenitor amplification at later developmental stages, entailing intriguing implications for neocortical expansion in evolution. Finally, despite a 3- to 5-fold increase of DGCR8 level in the mouse telencephalon, the composition, target preference and function of the DROSHA-dependent Microprocessor complex remain unaltered. Thus, we propose that DGCR8-dependent modulation of gene expression in corticogenesis is more complex than previously known, and possibly DROSHA-independent.

  2. Abundant Occurrence of Basal Radial Glia in the Subventricular Zone of Embryonic Neocortex of a Lissencephalic Primate, the Common Marmoset Callithrix jacchus

    Science.gov (United States)

    Kelava, Iva; Reillo, Isabel; Murayama, Ayako Y.; Kalinka, Alex T.; Stenzel, Denise; Tomancak, Pavel; Matsuzaki, Fumio; Lebrand, Cécile; Sasaki, Erika; Schwamborn, Jens C.; Okano, Hideyuki; Borrell, Víctor

    2012-01-01

    Subventricular zone (SVZ) progenitors are a hallmark of the developing neocortex. Recent studies described a novel type of SVZ progenitor that retains a basal process at mitosis, sustains expression of radial glial markers, and is capable of self-renewal. These progenitors, referred to here as basal radial glia (bRG), occur at high relative abundance in the SVZ of gyrencephalic primates (human) and nonprimates (ferret) but not lissencephalic rodents (mouse). Here, we analyzed the occurrence of bRG cells in the embryonic neocortex of the common marmoset Callithrix jacchus, a near-lissencephalic primate. bRG cells, expressing Pax6, Sox2 (but not Tbr2), glutamate aspartate transporter, and glial fibrillary acidic protein and retaining a basal process at mitosis, occur at similar relative abundance in the marmoset SVZ as in human and ferret. The proportion of progenitors in M-phase was lower in embryonic marmoset than developing ferret neocortex, raising the possibility of a longer cell cycle. Fitting the gyrification indices of 26 anthropoid species to an evolutionary model suggested that the marmoset evolved from a gyrencephalic ancestor. Our results suggest that a high relative abundance of bRG cells may be necessary, but is not sufficient, for gyrencephaly and that the marmoset's lissencephaly evolved secondarily by changing progenitor parameters other than progenitor type. PMID:22114084

  3. Laminar and Temporal Expression Dynamics of Coding and Noncoding RNAs in the Mouse Neocortex

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    Sofia Fertuzinhos

    2014-03-01

    Full Text Available The hallmark of the cerebral neocortex is its organization into six layers, each containing a characteristic set of cell types and synaptic connections. The transcriptional events involved in laminar development and function still remain elusive. Here, we employed deep sequencing of mRNA and small RNA species to gain insights into transcriptional differences among layers and their temporal dynamics during postnatal development of the mouse primary somatosensory neocortex. We identify a number of coding and noncoding transcripts with specific spatiotemporal expression and splicing patterns. We also identify signature trajectories and gene coexpression networks associated with distinct biological processes and transcriptional overlap between these processes. Finally, we provide data that allow the study of potential miRNA and mRNA interactions. Overall, this study provides an integrated view of the laminar and temporal expression dynamics of coding and noncoding transcripts in the mouse neocortex and a resource for studies of neurodevelopment and transcriptome.

  4. Comparative Analysis Between Flaviviruses Reveals Specific Neural Stem Cell Tropism for Zika Virus in the Mouse Developing Neocortex

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    Jean-Baptiste Brault

    2016-08-01

    Full Text Available The recent Zika outbreak in South America and French Polynesia was associated with an epidemic of microcephaly, a disease characterized by a reduced size of the cerebral cortex. Other members of the Flavivirus genus, including West Nile virus (WNV, can cause encephalitis but were not demonstrated to cause microcephaly. It remains unclear whether Zika virus (ZIKV and other flaviviruses may infect different cell populations in the developing neocortex and lead to distinct developmental defects. Here, we describe an assay to infect mouse E15 embryonic brain slices with ZIKV, WNV and dengue virus serotype 4 (DENV-4. We show that this tissue is able to support viral replication of ZIKV and WNV, but not DENV-4. Cell fate analysis reveals a remarkable tropism of ZIKV infection for neural stem cells. Closely related WNV displays a very different tropism of infection, with a bias towards neurons. We further show that ZIKV infection, but not WNV infection, impairs cell cycle progression of neural stem cells. Both viruses inhibited apoptosis at early stages of infection. This work establishes a powerful comparative approach to identify ZIKV-specific alterations in the developing neocortex and reveals specific preferential infection of neural stem cells by ZIKV.

  5. Mouse visual neocortex supports multiple stereotyped patterns of microcircuit activity.

    Science.gov (United States)

    Sadovsky, Alexander J; MacLean, Jason N

    2014-06-04

    Spiking correlations between neocortical neurons provide insight into the underlying synaptic connectivity that defines cortical microcircuitry. Here, using two-photon calcium fluorescence imaging, we observed the simultaneous dynamics of hundreds of neurons in slices of mouse primary visual cortex (V1). Consistent with a balance of excitation and inhibition, V1 dynamics were characterized by a linear scaling between firing rate and circuit size. Using lagged firing correlations between neurons, we generated functional wiring diagrams to evaluate the topological features of V1 microcircuitry. We found that circuit connectivity exhibited both cyclic graph motifs, indicating recurrent wiring, and acyclic graph motifs, indicating feedforward wiring. After overlaying the functional wiring diagrams onto the imaged field of view, we found properties consistent with Rentian scaling: wiring diagrams were topologically efficient because they minimized wiring with a modular architecture. Within single imaged fields of view, V1 contained multiple discrete circuits that were overlapping and highly interdigitated but were still distinct from one another. The majority of neurons that were shared between circuits displayed peri-event spiking activity whose timing was specific to the active circuit, whereas spike times for a smaller percentage of neurons were invariant to circuit identity. These data provide evidence that V1 microcircuitry exhibits balanced dynamics, is efficiently arranged in anatomical space, and is capable of supporting a diversity of multineuron spike firing patterns from overlapping sets of neurons. Copyright © 2014 the authors 0270-6474/14/347769-09$15.00/0.

  6. Multiple embryonic origins of nitric oxide synthase-expressing GABAergic neurons of the neocortex

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    Lorenza eMagno

    2012-09-01

    Full Text Available Cortical GABAergic interneurons in rodents originate in three subcortical regions: the medial ganglionic eminence (MGE, the lateral/caudal ganglionic eminence (LGE/CGE and the preoptic area (POA. Each of these neuroepithelial precursor domains contributes different interneuron subtypes to the cortex. nNOS-expressing neurons represent a heterogenous population of cortical interneurons. We examined the development of these cells in the mouse embryonic cortex and their abundance and distribution in adult animals. Using genetic lineage tracing in transgenic mice we find that nNOS type I cells originate only in the MGE whereas type II cells have a triple origin in the MGE, LGE/CGE and POA. The two populations are born at different times during development, occupy different layers in the adult cortex and have distinct neurochemical profiles. nNOS neurons are more numerous in the adult cortex than previously reported and constitute a significant proportion of the cortical interneuron population. Our data suggest that the heterogeneity of nNOS neurons in the cortex can be attributed to their multiple embryonic origins which likely impose distinct genetic specification programs.

  7. Degenerative changes and cell death in long-living homo- and heterotopic transplants from embryonic germ layers of rat neocortex.

    Science.gov (United States)

    Petrova, E S; Otellin, V A

    2003-09-01

    Morphological study of allotransplants of rat embryonic neocortex 14-18 months after transplantation into the neocortex, lateral cerebral ventricle, and sciatic nerve of adult animals revealed death of nerve and glial cells in the delayed postoperation period independently on the site of transplantation. After heterotopic transplantation the count of degenerated neurons was 2 times higher that after homotopic transplantation. In heterotopic transplants a considerable number of grafted neurons underwent reversible and irreversible degenerative changes accompanied by their premature aging. Neuronal death is probably determined by insufficiency of trophic influence from afferent structures and target tissues. We hypothesized that antiapoptotic preparations can be used for prevention of transplanted cell death. It was also found that degeneration of neurons was associated with impaired vascularization of transplants and pronounced immune reaction of the recipient in late posttransplantation period. Transplantation of embryonic brain structures can serve as a model system in studies concerning involutive and pathological processes in the central nervous system and in the search for factors improving survival of neurons.

  8. the production of mouse embryonic stem cells

    Indian Academy of Sciences (India)

    MADU

    What history tells us VII. Twenty-five years ago: the production of mouse embryonic stem cells ... cells into the cavity of the blastocyst, it will be possible to test the effect of .... to the use of efficient immunosuppressive drugs like cyclosporin – was ...

  9. Fate of Cajal-Retzius neurons in the postnatal mouse neocortex

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    Tara G Chowdhury

    2010-03-01

    Full Text Available Cajal-Retzius (CR neurons play a critical role in cortical neuronal migration, but their exact fate after the completion of neocortical lamination remains a mystery. Histological evidence has been unable to unequivocally determine whether these cells die or undergo a phenotypic transformation to become resident interneurons of Layer 1 in the adult neocortex. To determine their ultimate fate, we performed chronic in vivo two-photon imaging of identified CR neurons during postnatal development in mice that express the green fluorescent protein (GFP under the control of the early B-cell factor 2 (Ebf2 promoter. We find that, after birth, virtually all CR neurons in mouse neocortex express Ebf2. Although postnatal CR neurons undergo dramatic morphological transformations, they do not migrate to deeper layers. Instead, their gradual disappearance from the cortex is due to apoptotic death during the second postnatal week. A small fraction of CR neurons present at birth survive into adulthood. We conclude that, in addition to orchestrating cortical layering, a subset of CR neurons must play other roles beyond the third postnatal week.

  10. Hedgehog Signalling in the Embryonic Mouse Thymus

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    Alessandro Barbarulo

    2016-07-01

    Full Text Available T cells develop in the thymus, which provides an essential environment for T cell fate specification, and for the differentiation of multipotent progenitor cells into major histocompatibility complex (MHC-restricted, non-autoreactive T cells. Here we review the role of the Hedgehog signalling pathway in T cell development, thymic epithelial cell (TEC development, and thymocyte–TEC cross-talk in the embryonic mouse thymus during the last week of gestation.

  11. Generation of thalamic neurons from mouse embryonic stem cells.

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    Shiraishi, Atsushi; Muguruma, Keiko; Sasai, Yoshiki

    2017-04-01

    The thalamus is a diencephalic structure that plays crucial roles in relaying and modulating sensory and motor information to the neocortex. The thalamus develops in the dorsal part of the neural tube at the level of the caudal forebrain. However, the molecular mechanisms that are essential for thalamic differentiation are still unknown. Here, we have succeeded in generating thalamic neurons from mouse embryonic stem cells (mESCs) by modifying the default method that induces the most-anterior neural type in self-organizing culture. A low concentration of the caudalizing factor insulin and a MAPK/ERK kinase inhibitor enhanced the expression of the caudal forebrain markers Otx2 and Pax6. BMP7 promoted an increase in thalamic precursors such as Tcf7l2 + /Gbx2 + and Tcf7l2 + /Olig3 + cells. mESC thalamic precursors began to express the glutamate transporter vGlut2 and the axon-specific marker VGF, similar to mature projection neurons. The mESC thalamic neurons extended their axons to cortical layers in both organotypic culture and subcortical transplantation. Thus, we have identified the minimum elements sufficient for in vitro generation of thalamic neurons. These findings expand our knowledge of thalamic development. © 2017. Published by The Company of Biologists Ltd.

  12. THIP, a hypnotic and antinociceptive drug, enhances a tonic GABAA receptor mediated conductance in mouse neocortex

    DEFF Research Database (Denmark)

    Drasbek, Kim Ryun; Jensen, Kimmo

    2006-01-01

    its cellular actions in the neocortex are uncertain, we studied the effects of THIP on neurons in slices of frontoparietal neocortex of 13- to 19-day-old (P13-19) mice. Using whole-cell patch-clamp recordings, we found that the clinically relevant THIP concentration of 1 μM induced a robust tonic GABA...... suggest that THIP activates an extrasynaptic GABA(A) receptor-mediated conductance in the neocortex, which may alter the cortical network activity....

  13. Defective neuronal migration and inhibition of bipolar to multipolar transition of migrating neural cells by Mesoderm-Specific Transcript, Mest, in the developing mouse neocortex.

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    Ji, Liting; Bishayee, Kausik; Sadra, Ali; Choi, Seunghyuk; Choi, Wooyul; Moon, Sungho; Jho, Eek-Hoon; Huh, Sung-Oh

    2017-07-04

    Brain developmental disorders such as lissencephaly can result from faulty neuronal migration and differentiation during the formation of the mammalian neocortex. The cerebral cortex is a modular structure, where developmentally, newborn neurons are generated as a neuro-epithelial sheet and subsequently differentiate, migrate and organize into their final positions in the cerebral cortical plate via a process involving both tangential and radial migration. The specific role of Mest, an imprinted gene, in neuronal migration has not been previously studied. In this work, we reduced expression of Mest with in utero electroporation of neuronal progenitors in the developing embryonic mouse neocortex. Reduction of Mest levels by shRNA significantly reduced the number of neurons migrating to the cortical plate. Also, Mest-knockdown disrupted the transition of bipolar neurons into multipolar neurons migrating out of the sub-ventricular zone region. The migrating neurons also adopted a more tangential migration pattern upon knockdown of the Mest message, losing their potential to attach to radial glia cells, required for radial migration. The differentiation and migration properties of neurons via Wnt-Akt signaling were affected by Mest changes. In addition, miR-335, encoded in a Mest gene intron, was identified as being responsible for blocking the default tangential migration of the neurons. Our results suggest that Mest and its intron product, miR-335, play important roles in neuronal migration with Mest regulating the morphological transition of primary neurons required in the formation of the mammalian neocortex. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.

  14. Quantitative analysis of neuronal mosaic formation in the mouse neocortex and hippocampus

    International Nuclear Information System (INIS)

    Reznikov, K.Yu.; Nazarevskaya, G.D.; Deryabin, V.E.

    1987-01-01

    The authors obtain mathematical confirmation of the nonrandomness of mosaic formation of neuronal groups in the cerebral cortex, characterize this process quantitatively, and compare its scale with the formation of the modular organization of the cortex. Mice were used in the experiments and were injected with 3 H-thymidine while pregnant. Mapping in the neocortex was carried out on frontal semithin brain sections from mice receiving 3 H-thymidine from E15 through E17, whereas mapping in the hippocampus was carried out on paraffin and semithin frontal brain sections from animals receiving the isotope from E13 through E17

  15. Impact of 2-bromopropane on mouse embryonic stem cells and ...

    African Journals Online (AJOL)

    This study shows that 2-BP (5 to 10 μM) induces apoptotic processes in mouse embryonic stem cells (ESC-B5), but exerts no effects at treatment dosages below 5 μM. In ESC-B5 cells, 2-BP directly increased the content of reactive oxygen species (ROS), significantly increased the cytoplasmic free calcium and nitric oxide ...

  16. In vitro differentiation of mouse embryonic stem cells into functional ...

    African Journals Online (AJOL)

    Studies have shown that embryonic stem (ES) cells can be successfully differentiated into liver cells, which offer the potential unlimited cell source for a variety of end-stage liver disease. In our study, in order to induce mouse ES cells to differentiate into hepatocyte-like cells under chemically defined conditions, ES cells ...

  17. In vitro differentiation of mouse embryonic stem cells into neurons of the dorsal forebrain

    Czech Academy of Sciences Publication Activity Database

    Jing, Y.; Machoň, Ondřej; Hampl, Aleš; Dvořák, P.; Xing, Y.; Krauss, S.

    2011-01-01

    Roč. 31, č. 5 (2011), s. 715-727 ISSN 0272-4340 R&D Projects: GA ČR GA204/08/1618 Institutional research plan: CEZ:AV0Z50520514; CEZ:AV0Z50390512 Keywords : embryonic stem cells * differentiation * neocortex Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.969, year: 2011

  18. Intact calcium signaling in adrenergic-deficient embryonic mouse hearts.

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    Peoples, Jessica N; Taylor, David G; Katchman, Alexander N; Ebert, Steven N

    2018-01-22

    Mouse embryos that lack the ability to produce the adrenergic hormones, norepinephrine (NE) and epinephrine (EPI), due to disruption of the dopamine beta-hydroxylase (Dbh -/- ) gene inevitably perish from heart failure during mid-gestation. Since adrenergic stimulation is well-known to enhance calcium signaling in developing as well as adult myocardium, and impairments in calcium signaling are typically associated with heart failure, we hypothesized that adrenergic-deficient embryonic hearts would display deficiencies in cardiac calcium signaling relative to adrenergic-competent controls at a developmental stage immediately preceding the onset of heart failure, which first appears beginning or shortly after mouse embryonic day 10.5 (E10.5). To test this hypothesis, we used ratiometric fluorescent calcium imaging techniques to measure cytosolic calcium transients, [Ca 2+ ] i in isolated E10.5 mouse hearts. Our results show that spontaneous [Ca 2+ ] i oscillations were intact and robustly responded to a variety of stimuli including extracellular calcium (5 mM), caffeine (5 mM), and NE (100 nM) in a manner that was indistinguishable from controls. Further, we show similar patterns of distribution (via immunofluorescent histochemical staining) and activity (via patch-clamp recording techniques) for the major voltage-gated plasma membrane calcium channel responsible for the L-type calcium current, I Ca,L , in adrenergic-deficient and control embryonic cardiac cells. These results demonstrate that despite the absence of vital adrenergic hormones that consistently leads to embryonic lethality in vivo, intracellular and extracellular calcium signaling remain essentially intact and functional in embryonic mouse hearts through E10.5. These findings suggest that adrenergic stimulation is not required for the development of intracellular calcium oscillations or extracellular calcium signaling through I Ca,L and that aberrant calcium signaling does not likely contribute

  19. Differentiation of Mouse Embryonic Stem Cells into Ventral Foregut Precursors

    DEFF Research Database (Denmark)

    Rothová, Michaela; Hölzenspies, Jurriaan J; Livigni, Alessandra

    2016-01-01

    Anterior definitive endoderm (ADE), the ventral foregut precursor, is both an important embryonic signaling center and a unique multipotent precursor of liver, pancreas, and other organs. Here, a method is described for the differentiation of mouse embryonic stem cells (mESCs) to definitive...... endoderm with pronounced anterior character. ADE-containing cultures can be produced in vitro by suspension (embryoid body) culture or in a serum-free adherent monolayer culture. ESC-derived ADE cells are committed to endodermal fates and can undergo further differentiation in vitro towards ventral foregut...

  20. Enhanced astrocytic nitric oxide production and neuronal modifications in the neocortex of a NOS2 mutant mouse.

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    Yossi Buskila

    Full Text Available BACKGROUND: It has been well accepted that glial cells in the central nervous system (CNS produce nitric oxide (NO through the induction of a nitric oxide synthase isoform (NOS2 only in response to various insults. Recently we described rapid astroglial, NOS2-dependent, NO production in the neocortex of healthy mice on a time scale relevant to neuronal activity. To explore a possible role for astroglial NOS2 in normal brain function we investigated a NOS2 knockout mouse (B6;129P2-Nos2(tm1Lau/J, Jackson Laboratory. Previous studies of this mouse strain revealed mainly altered immune responses, but no compensatory pathways and no CNS abnormalities have been reported. METHODOLOGY/PRINCIPAL FINDINGS: To our surprise, using NO imaging in brain slices in combination with biochemical methods we uncovered robust NO production by neocortical astrocytes of the NOS2 mutant. These findings indicate the existence of an alternative pathway that increases basal NOS activity. In addition, the astroglial mutation instigated modifications of neuronal attributes, shown by changes in the membrane properties of pyramidal neurons, and revealed in distinct behavioral abnormalities characterized by an increase in stress-related parameters. CONCLUSIONS/SIGNIFICANCE: The results strongly indicate the involvement of astrocytic-derived NO in modifying the activity of neuronal networks. In addition, the findings corroborate data linking NO signaling with stress-related behavior, and highlight the potential use of this genetic model for studies of stress-susceptibility. Lastly, our results beg re-examination of previous studies that used this mouse strain to examine the pathophysiology of brain insults, assuming lack of astrocytic nitrosative reaction.

  1. MicroRNA Cluster miR-17-92 Regulates Neural Stem Cell Expansion and Transition to Intermediate Progenitors in the Developing Mouse Neocortex

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    Shan Bian

    2013-05-01

    Full Text Available During development of the embryonic neocortex, tightly regulated expansion of neural stem cells (NSCs and their transition to intermediate progenitors (IPs are critical for normal cortical formation and function. Molecular mechanisms that regulate NSC expansion and transition remain unclear. Here, we demonstrate that the microRNA (miRNA miR-17-92 cluster is required for maintaining proper populations of cortical radial glial cells (RGCs and IPs through repression of Pten and Tbr2 protein. Knockout of miR-17-92 and its paralogs specifically in the developing neocortex restricts NSC proliferation, suppresses RGC expansion, and promotes transition of RGCs to IPs. Moreover, Pten and Tbr2 protectors specifically block silencing activities of endogenous miR-17-92 and control proper numbers of RGCs and IPs in vivo. Our results demonstrate a critical role for miRNAs in promoting NSC proliferation and modulating the cell-fate decision of generating distinct neural progenitors in the developing neocortex.

  2. Photo-transfection of mouse embryonic stem cells with plasmid DNA using femtosecond laser pulses

    CSIR Research Space (South Africa)

    Thobakgale, Lebogang

    2017-01-01

    Full Text Available This presentation is about the photo-transfection of mouse embryonic stem cells with plasmid DNA using femtosecond laser pulses. It outlines the background on embryonic stem cells (ES) and phototransfection....

  3. Mouse oocytes nucleoli rescue embryonic development of porcine enucleolated oocytes.

    Science.gov (United States)

    Morovic, Martin; Strejcek, Frantisek; Nakagawa, Shoma; Deshmukh, Rahul S; Murin, Matej; Benc, Michal; Fulka, Helena; Kyogoku, Hirohisa; Pendovski, Lazo; Fulka, Josef; Laurincik, Jozef

    2017-12-01

    It is well known that nucleoli of fully grown mammalian oocytes are indispensable for embryonic development. Therefore, the embryos originated from previously enucleolated (ENL) oocytes undergo only one or two cleavages and then their development ceases. In our study the interspecies (mouse/pig) nucleolus transferred embryos (NuTE) were produced and their embryonic development was analyzed by autoradiography, transmission electron microscopy (TEM) and immunofluorescence (C23 and upstream binding factor (UBF)). Our results show that the re-injection of isolated oocyte nucleoli, either from the pig (P + P) or mouse (P + M), into previously enucleolated and subsequently matured porcine oocytes rescues their development after parthenogenetic activation and some of these develop up to the blastocyst stage (P + P, 11.8%; P + M, 13.5%). In nucleolus re-injected 8-cell and blastocyst stage embryos the number of nucleoli labeled with C23 in P + P and P + M groups was lower than in control (non-manipulated) group. UBF was localized in small foci within the nucleoli of blastocysts in control and P + P embryos, however, in P + M embryos the labeling was evenly distributed in the nucleoplasm. The TEM and autoradiographic evaluations showed the formation of functional nucleoli and de novo rRNA synthesis at the 8-cell stage in both, control and P + P group. In the P + M group the formation of comparable nucleoli was delayed. In conclusion, our results indicate that the mouse nucleolus can rescue embryonic development of enucleolated porcine oocytes, but the localization of selected nucleolar proteins, the timing of transcription activation and the formation of the functional nucleoli in NuTE compared with control group show evident aberrations.

  4. Dual effects of fluoxetine on mouse early embryonic development

    International Nuclear Information System (INIS)

    Kim, Chang-Woon; Choe, Changyong; Kim, Eun-Jin; Lee, Jae-Ik; Yoon, Sook-Young; Cho, Young-Woo; Han, Sunkyu; Tak, Hyun-Min; Han, Jaehee; Kang, Dawon

    2012-01-01

    Fluoxetine, a selective serotonin reuptake inhibitor, regulates a variety of physiological processes, such as cell proliferation and apoptosis, in mammalian cells. Little is known about the role of fluoxetine in early embryonic development. This study was undertaken to investigate the effect of fluoxetine during mouse early embryonic development. Late two-cell stage embryos (2-cells) were cultured in the presence of various concentrations of fluoxetine (1 to 50 μM) for different durations. When late 2-cells were incubated with 5 μM fluoxetine for 6 h, the percentage that developed into blastocysts increased compared to the control value. However, late 2-cells exposed to fluoxetine (5 μM) over 24 h showed a reduction in blastocyst formation. The addition of fluoxetine (5 μM) together with KN93 or KN62 (calcium/calmodulin-dependent protein kinase II (CaMKII) inhibitors) failed to increase blastocyst formation. Fluoxetine treatment inhibited TREK-1 and TREK-2, members of the two-pore domain K + channel family expressed in mouse embryos, activities, indicating that fluoxetine-induced membrane depolarization in late 2-cells might have resulted from TREK inhibition. In addition, long-term exposure to fluoxetine altered the TREK mRNA expression levels. Furthermore, injection of siRNA targeting TREKs significantly decreased blastocyst formation by ∼ 30% compared to injection of scrambled siRNA. Long-term exposure of fluoxetine had no effect on blastocyst formation of TREK deficient embryos. These results indicate that low-dose and short-term exposures of late 2-cells to fluoxetine probably increase blastocyst formation through activation of CaMKII-dependent signal transduction pathways, whereas long-term exposure decreases mouse early embryonic development through inhibition of TREK channel gating. Highlights: ► Short-term exposure of 2-cells to fluoxetine enhances mouse blastocyst formation. ► The enhancive effect of fluoxetine is resulted from CaMKII activation

  5. Dual effects of fluoxetine on mouse early embryonic development

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Chang-Woon [Department of Physiology and Institute of Health Sciences, Gyeongsang National University School of Medicine, Jinju 660-751 (Korea, Republic of); Department of Obstetrics and Gynecology, Samsung Changwon Hospital, Sungkyunkwan University, Changwon 630-723 (Korea, Republic of); Choe, Changyong [National Institute of Animal Science, RDA, Cheonan 330-801 (Korea, Republic of); Kim, Eun-Jin [Department of Physiology and Institute of Health Sciences, Gyeongsang National University School of Medicine, Jinju 660-751 (Korea, Republic of); Lee, Jae-Ik [Department of Obstetrics and Gynecology, Gyeongsang National University Hospital, Jinju 660-702 (Korea, Republic of); Yoon, Sook-Young [Fertility Center of CHA Gangnam Medical Center, CHA University, Seoul 135-081 (Korea, Republic of); Cho, Young-Woo; Han, Sunkyu; Tak, Hyun-Min; Han, Jaehee [Department of Physiology and Institute of Health Sciences, Gyeongsang National University School of Medicine, Jinju 660-751 (Korea, Republic of); Kang, Dawon, E-mail: dawon@gnu.ac.kr [Department of Physiology and Institute of Health Sciences, Gyeongsang National University School of Medicine, Jinju 660-751 (Korea, Republic of)

    2012-11-15

    Fluoxetine, a selective serotonin reuptake inhibitor, regulates a variety of physiological processes, such as cell proliferation and apoptosis, in mammalian cells. Little is known about the role of fluoxetine in early embryonic development. This study was undertaken to investigate the effect of fluoxetine during mouse early embryonic development. Late two-cell stage embryos (2-cells) were cultured in the presence of various concentrations of fluoxetine (1 to 50 μM) for different durations. When late 2-cells were incubated with 5 μM fluoxetine for 6 h, the percentage that developed into blastocysts increased compared to the control value. However, late 2-cells exposed to fluoxetine (5 μM) over 24 h showed a reduction in blastocyst formation. The addition of fluoxetine (5 μM) together with KN93 or KN62 (calcium/calmodulin-dependent protein kinase II (CaMKII) inhibitors) failed to increase blastocyst formation. Fluoxetine treatment inhibited TREK-1 and TREK-2, members of the two-pore domain K{sup +} channel family expressed in mouse embryos, activities, indicating that fluoxetine-induced membrane depolarization in late 2-cells might have resulted from TREK inhibition. In addition, long-term exposure to fluoxetine altered the TREK mRNA expression levels. Furthermore, injection of siRNA targeting TREKs significantly decreased blastocyst formation by ∼ 30% compared to injection of scrambled siRNA. Long-term exposure of fluoxetine had no effect on blastocyst formation of TREK deficient embryos. These results indicate that low-dose and short-term exposures of late 2-cells to fluoxetine probably increase blastocyst formation through activation of CaMKII-dependent signal transduction pathways, whereas long-term exposure decreases mouse early embryonic development through inhibition of TREK channel gating. Highlights: ► Short-term exposure of 2-cells to fluoxetine enhances mouse blastocyst formation. ► The enhancive effect of fluoxetine is resulted from Ca

  6. Visualization of Functional Neuropeptide Y Receptors in the Mouse Hippocampus and Neocortex Using [35S]GTPγS Binding

    DEFF Research Database (Denmark)

    Elbrønd-Bek, Heidi; Gøtzsche, Casper René; Skinbjerg, Mette

    2015-01-01

    The peptide transmitter neuropeptide Y (NPY) has been implicated in a plethora of actions in the central nervous system, including the hippocampus and neocortex (NeoCx). Previous studies using traditional receptor autoradiography show that NPY receptor binding is altered under various pathophysio......The peptide transmitter neuropeptide Y (NPY) has been implicated in a plethora of actions in the central nervous system, including the hippocampus and neocortex (NeoCx). Previous studies using traditional receptor autoradiography show that NPY receptor binding is altered under various...

  7. Mouse embryonic retina delivers information controlling cortical neurogenesis.

    Directory of Open Access Journals (Sweden)

    Ciro Bonetti

    2010-12-01

    Full Text Available The relative contribution of extrinsic and intrinsic mechanisms to cortical development is an intensely debated issue and an outstanding question in neurobiology. Currently, the emerging view is that interplay between intrinsic genetic mechanisms and extrinsic information shape different stages of cortical development. Yet, whereas the intrinsic program of early neocortical developmental events has been at least in part decoded, the exact nature and impact of extrinsic signaling are still elusive and controversial. We found that in the mouse developing visual system, acute pharmacological inhibition of spontaneous retinal activity (retinal waves-RWs during embryonic stages increase the rate of corticogenesis (cell cycle withdrawal. Furthermore, early perturbation of retinal spontaneous activity leads to changes of cortical layer structure at a later time point. These data suggest that mouse embryonic retina delivers long-distance information capable of modulating cell genesis in the developing visual cortex and that spontaneous activity is the candidate long-distance acting extrinsic cue mediating this process. In addition, these data may support spontaneous activity to be a general signal coordinating neurogenesis in other developing sensory pathways or areas of the central nervous system.

  8. GATA-1 directly regulates Nanog in mouse embryonic stem cells

    Energy Technology Data Exchange (ETDEWEB)

    Li, Wen-Zhong; Ai, Zhi-Ying [College of Life Sciences, Northwest A& F University, Yangling 712100 (China); Key Laboratory of Animal Biotechnology, Ministry of Agriculture, Northwest A& F University, Yangling 712100 (China); Wang, Zhi-Wei [School of Life Sciences and Medical Center, University of Science and Technology of China, Hefei, Anhui 230027 (China); Chen, Lin-Lin [College of Life Sciences, Northwest A& F University, Yangling 712100 (China); Key Laboratory of Animal Biotechnology, Ministry of Agriculture, Northwest A& F University, Yangling 712100 (China); Guo, Ze-Kun, E-mail: gzknwaf@126.com [College of Veterinary Medicine, Northwest A& F University, Yangling 712100 (China); Key Laboratory of Animal Biotechnology, Ministry of Agriculture, Northwest A& F University, Yangling 712100 (China); Zhang, Yong, E-mail: zylabnwaf@126.com [College of Veterinary Medicine, Northwest A& F University, Yangling 712100 (China); Key Laboratory of Animal Biotechnology, Ministry of Agriculture, Northwest A& F University, Yangling 712100 (China)

    2015-09-25

    Nanog safeguards pluripotency in mouse embryonic stem cells (mESCs). Insight into the regulation of Nanog is important for a better understanding of the molecular mechanisms that control pluripotency of mESCs. In a silico analysis, we identify four GATA-1 putative binding sites in Nanog proximal promoter. The Nanog promoter activity can be significantly repressed by ectopic expression of GATA-1 evidenced by a promoter reporter assay. Mutation studies reveal that one of the four putative binding sites counts for GATA-1 repressing Nanog promoter activity. Direct binding of GATA-1 on Nanog proximal promoter is confirmed by electrophoretic mobility shift assay and chromatin immunoprecipitation. Our data provide new insights into the expanded regulatory circuitry that coordinates Nanog expression. - Highlights: • The Nanog proximal promoter conceives functional element for GATA-1. • GATA-1 occupies the Nanog proximal promoter in vitro and in vivo. • GATA-1 transcriptionally suppresses Nanog.

  9. Comparison of the metabolic activation of environmental carcinogens in mouse embryonic stem cells and mouse embryonic fibroblasts

    Science.gov (United States)

    Krais, Annette M.; Mühlbauer, Karl-Rudolf; Kucab, Jill E.; Chinbuah, Helena; Cornelius, Michael G.; Wei, Quan-Xiang; Hollstein, Monica; Phillips, David H.; Arlt, Volker M.; Schmeiser, Heinz H.

    2015-01-01

    We compared mouse embryonic stem (ES) cells and fibroblasts (MEFs) for their ability to metabolically activate the environmental carcinogens benzo[a]pyrene (BaP), 3-nitrobenzanthrone (3-NBA) and aristolochic acid I (AAI), measuring DNA adduct formation by 32P-postlabelling and expression of xenobiotic-metabolism genes by quantitative real-time PCR. At 2 μM, BaP induced Cyp1a1 expression in MEFs to a much greater extent than in ES cells and formed 45 times more adducts. Nqo1 mRNA expression was increased by 3-NBA in both cell types but induction was higher in MEFs, as was adduct formation. For AAI, DNA binding was over 450 times higher in MEFs than in ES cells, although Nqo1 and Cyp1a1 transcriptional levels did not explain this difference. We found higher global methylation of DNA in ES cells than in MEFs, which suggests higher chromatin density and lower accessibility of the DNA to DNA damaging agents in ES cells. However, AAI treatment did not alter DNA methylation. Thus mouse ES cells and MEFs have the metabolic competence to activate a number of environmental carcinogens, but MEFs have lower global DNA methylation and higher metabolic capacity than mouse ES cells. PMID:25230394

  10. Specialized mouse embryonic stem cells for studying vascular development.

    Science.gov (United States)

    Glaser, Drew E; Burns, Andrew B; Hatano, Rachel; Medrzycki, Magdalena; Fan, Yuhong; McCloskey, Kara E

    2014-01-01

    Vascular progenitor cells are desirable in a variety of therapeutic strategies; however, the lineage commitment of endothelial and smooth muscle cell from a common progenitor is not well-understood. Here, we report the generation of the first dual reporter mouse embryonic stem cell (mESC) lines designed to facilitate the study of vascular endothelial and smooth muscle development in vitro. These mESC lines express green fluorescent protein (GFP) under the endothelial promoter, Tie-2, and Discomsoma sp. red fluorescent protein (RFP) under the promoter for alpha-smooth muscle actin (α-SMA). The lines were then characterized for morphology, marker expression, and pluripotency. The mESC colonies were found to exhibit dome-shaped morphology, alkaline phosphotase activity, as well as expression of Oct 3/4 and stage-specific embryonic antigen-1. The mESC colonies were also found to display normal karyotypes and are able to generate cells from all three germ layers, verifying pluripotency. Tissue staining confirmed the coexpression of VE (vascular endothelial)-cadherin with the Tie-2 GFP+ expression on endothelial structures and smooth muscle myosin heavy chain with the α-SMA RFP+ smooth muscle cells. Lastly, it was verified that the developing mESC do express Tie-2 GFP+ and α-SMA RFP+ cells during differentiation and that the GFP+ cells colocalize with the vascular-like structures surrounded by α-SMA-RFP cells. These dual reporter vascular-specific mESC permit visualization and cell tracking of individual endothelial and smooth muscle cells over time and in multiple dimensions, a powerful new tool for studying vascular development in real time.

  11. Gene function in early mouse embryonic stem cell differentiation

    Directory of Open Access Journals (Sweden)

    Campbell Pearl A

    2007-03-01

    Full Text Available Abstract Background Little is known about the genes that drive embryonic stem cell differentiation. However, such knowledge is necessary if we are to exploit the therapeutic potential of stem cells. To uncover the genetic determinants of mouse embryonic stem cell (mESC differentiation, we have generated and analyzed 11-point time-series of DNA microarray data for three biologically equivalent but genetically distinct mESC lines (R1, J1, and V6.5 undergoing undirected differentiation into embryoid bodies (EBs over a period of two weeks. Results We identified the initial 12 hour period as reflecting the early stages of mESC differentiation and studied probe sets showing consistent changes of gene expression in that period. Gene function analysis indicated significant up-regulation of genes related to regulation of transcription and mRNA splicing, and down-regulation of genes related to intracellular signaling. Phylogenetic analysis indicated that the genes showing the largest expression changes were more likely to have originated in metazoans. The probe sets with the most consistent gene changes in the three cell lines represented 24 down-regulated and 12 up-regulated genes, all with closely related human homologues. Whereas some of these genes are known to be involved in embryonic developmental processes (e.g. Klf4, Otx2, Smn1, Socs3, Tagln, Tdgf1, our analysis points to others (such as transcription factor Phf21a, extracellular matrix related Lama1 and Cyr61, or endoplasmic reticulum related Sc4mol and Scd2 that have not been previously related to mESC function. The majority of identified functions were related to transcriptional regulation, intracellular signaling, and cytoskeleton. Genes involved in other cellular functions important in ESC differentiation such as chromatin remodeling and transmembrane receptors were not observed in this set. Conclusion Our analysis profiles for the first time gene expression at a very early stage of m

  12. In vitro differentiation of mouse embryonic stem cells into functional ...

    African Journals Online (AJOL)

    Jane

    2011-08-22

    Aug 22, 2011 ... hepatocyte transplantation therapy and toxicity screening in drug discovery. Key words: Embryonic stem cells, hepatic-like cells, in vitro differentiation, sodium butyrate, ... from embryonic stem (ES) cell or induced pluripotent.

  13. Mouse Embryonic Stem Cell Adherent Cell Differentiation and Cytotoxicity (ACDC) assay

    Science.gov (United States)

    The Embryonic Stem Cell Test (EST) is an assay which evaluates xenobiotic-induced effects using three endpoints: mouse embryonic stem cell (mESC) differentiation, mESC viability, and 3T3-cell viability. Our research goal was to develop an improved high-throughput assay by establi...

  14. Embryonic Lethality of Mitochondrial Pyruvate Carrier 1 Deficient Mouse Can Be Rescued by a Ketogenic Diet

    OpenAIRE

    Vanderperre, Beno?t; Herzig, S?bastien; Krznar, Petra; H?rl, Manuel; Ammar, Zeinab; Montessuit, Sylvie; Pierredon, Sandra; Zamboni, Nicola; Martinou, Jean-Claude

    2016-01-01

    Mitochondrial import of pyruvate by the mitochondrial pyruvate carrier (MPC) is a central step which links cytosolic and mitochondrial intermediary metabolism. To investigate the role of the MPC in mammalian physiology and development, we generated a mouse strain with complete loss of MPC1 expression. This resulted in embryonic lethality at around E13.5. Mouse embryonic fibroblasts (MEFs) derived from mutant mice displayed defective pyruvate-driven respiration as well as perturbed metabolic p...

  15. Resveratrol Enhances Self-Renewal of Mouse Embryonic Stem Cells.

    Science.gov (United States)

    Li, Na; Du, Zhaoyu; Shen, Qiaoyan; Lei, Qijing; Zhang, Ying; Zhang, Mengfei; Hua, Jinlian

    2017-07-01

    Resveratrol (RSV) has been shown to affect the differentiation of several types of stem cells, while the detailed mechanism is elusive. Here, we aim to investigate the function of RSV in self-renewal of mouse embryonic stem cells (ESCs) and the related mechanisms. In contrast with its reported roles, we found unexpectedly that differentiated ESCs or iPSCs treated by RSV would not show further differentiation, but regained a naïve pluripotency state with higher expressions of core transcriptional factors and with the ability to differentiate into all three germ layers when transplanted in vivo. In accordance with these findings, RSV also enhanced cell cycle progression of ESCs via regulating cell cycle-related proteins. Finally, enhanced activation of JAK/STAT3 signaling pathway and suppressed activation of mTOR were found essential in enhancing the self-renewal of ESCs by RSV. Our finding discovered a novel function of RSV in enhancing the self-renewal of ESCs, and suggested that the timing of treatment and concentration of RSV determined the final effect of it. Our work may contribute to understanding of RSV in the self-renewal maintenance of pluripotent stem cells, and may also provide help to the generation and maintenance of iPSCs in vitro. J. Cell. Biochem. 118: 1928-1935, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  16. Rab3 proteins involved in vesicle biogenesis and priming in embryonic mouse chromaffin cells

    DEFF Research Database (Denmark)

    Schonn, Jean-Sébastien; van Weering, Jan R T; Mohrmann, Ralf

    2010-01-01

    The four Rab3 paralogs A-D are involved in exocytosis, but their mechanisms of action are hard to study due to functional redundancy. Here we used a quadruple Rab3 knock-out (rab3a, rab3b, rab3c, rab3d null, here denoted ABCD(-/-)) mouse line to investigate Rab3 function in embryonic mouse adrena...

  17. Dioxin induces genomic instability in mouse embryonic fibroblasts.

    Directory of Open Access Journals (Sweden)

    Merja Korkalainen

    Full Text Available Ionizing radiation and certain other exposures have been shown to induce genomic instability (GI, i.e., delayed genetic damage observed many cell generations later in the progeny of the exposed cells. The aim of this study was to investigate induction of GI by a nongenotoxic carcinogen, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD. Mouse embryonic fibroblasts (C3H10T1/2 were exposed to 1, 10 or 100 nM TCDD for 2 days. Micronuclei (MN and expression of selected cancer-related genes were assayed both immediately and at a delayed point in time (8 days. For comparison, similar experiments were done with cadmium, a known genotoxic agent. TCDD treatment induced an elevated frequency of MN at 8 days, but not directly after the exposure. TCDD-induced alterations in gene expression were also mostly delayed, with more changes observed at 8 days than at 2 days. Exposure to cadmium produced an opposite pattern of responses, with pronounced effects immediately after exposure but no increase in MN and few gene expression changes at 8 days. Although all responses to TCDD alone were delayed, menadione-induced DNA damage (measured by the Comet assay, was found to be increased directly after a 2-day TCDD exposure, indicating that the stability of the genome was compromised already at this time point. The results suggested a flat dose-response relationship consistent with dose-response data reported for radiation-induced GI. These findings indicate that TCDD, although not directly genotoxic, induces GI, which is associated with impaired DNA damage response.

  18. Cultured embryonic non-innervated mouse muzzle is capable of generating a whisker pattern.

    Science.gov (United States)

    Andrés, F L; Van Der Loos, H

    1983-01-01

    The whisker pattern on the muzzle of the mouse is mapped in the contralateral parietal neocortex, each whisker follicle projecting to its own multineuronal unit ('barrel'). To determine the role, if any, of the peripheral innervation in the establishment of the vibrissal array, we cultured non-innervated prospective whiskerpads from 9- and 10-day-old embryos, mostly on chorioallantoic membrane. The results show that skin, alone, is capable of generating the whisker pattern, thus adducing a strong argument for the hypothesis that the central brain maps have their origin in the periphery. Copyright © 1983. Published by Elsevier Ltd.

  19. Lipofection improves gene targeting efficiency in E14 TG2a mouse embryonic stem cells

    OpenAIRE

    Sandra M. López-Heydeck

    2009-01-01

    Electroporation has been the method of election for transfection of murine embryonic stem cells for over 15 years; however, it is a time consuming protocol because it requires large amounts of DNA and cells, as well as expensive and delicate equipment. Lipofection is a transfection method that requires lower amounts of cells and DNA than electroporation, and has proven to be effi cient in a large number of cell lines. It has been shown that after lipofection, mouse embryonic stem cells remain...

  20. Redox Disrupting Potential of ToxCast™Chemicals Ranked by Activity in Mouse Embryonic Stem Cells

    Science.gov (United States)

    Little is known regarding the adverse outcome pathways responsible for developmental toxicity following exposure to chemicals. An evaluation of Toxoast™ Phase I chemicals in an adherent mouse embryonic stem cell (mESC) assay revealed a redox sensitive pathway that correlated with...

  1. REDOX DISRUPTING POTENTIAL OF TOXCAST CHEMICALS RANKED BY ACTIVITY IN MOUSE EMBRYONIC STEM CELLS

    Science.gov (United States)

    To gain insight regarding the adverse outcome pathways leading to developmental toxicity following exposure to chemicals, we evaluated ToxCast™ Phase I chemicals in an adherent mouse embryonic stem cell (mESC) assay and identified a redox sensitive pathway that correlated with al...

  2. Fingerprinting of neurotoxic compounds using a mouse embryonic stem cell dual luminescence reporter assay

    NARCIS (Netherlands)

    Colaianna, M.; Ilmjärv, S.; Peterson, H.; Ilse Kern, I.; Julien, S.; Baquié, M.; allocca, G.; Bosgra, S.; Sachinidis, A.; Hengstler, J.G.; Leist, M.; Krause, K.H.

    2017-01-01

    Identification of neurotoxic drugs and environmental chemicals is an important challenge. However, only few tools to address this topic are available. The aim of this study was to develop a neurotoxicity/developmental neurotoxicity (DNT) test system, using the pluripotent mouse embryonic stem cell

  3. Assessment of a 42 metal salts chemical library in mouse embryonic stem cells

    Science.gov (United States)

    The developmental effects of xenobiotics on differentiation can be profiled using mouse embryonic stem cells (mESCs). The adherent cell differentiation and cytotoxicity (ACDC) technique was used to evaluate a library of 42 metal and metaloid salts. Jl mESCs were allowed to prolif...

  4. In vitro pancreas organogenesis from dispersed mouse embryonic progenitors

    DEFF Research Database (Denmark)

    Greggio, Chiara; De Franceschi, Filippo; Figueiredo-Larsen, Evan Manuel

    2014-01-01

    The pancreas is an essential organ that regulates glucose homeostasis and secretes digestive enzymes. Research on pancreas embryogenesis has led to the development of protocols to produce pancreatic cells from stem cells (1). The whole embryonic organ can be cultured at multiple stages...... expanding progenitors and differentiate into endocrine, acinar and ductal cells and which spontaneously self-organize to resemble the embryonic pancreas. We show here that the in vitro process recapitulates many aspects of natural pancreas development. This culture system is suitable to investigate how...... cells cooperate to form an organ by reducing its initial complexity to few progenitors. It is a model that reproduces the 3D architecture of the pancreas and that is therefore useful to study morphogenesis, including polarization of epithelial structures and branching. It is also appropriate to assess...

  5. Generation of stomach tissue from mouse embryonic stem cells.

    Science.gov (United States)

    Noguchi, Taka-aki K; Ninomiya, Naoto; Sekine, Mari; Komazaki, Shinji; Wang, Pi-Chao; Asashima, Makoto; Kurisaki, Akira

    2015-08-01

    Successful pluripotent stem cell differentiation methods have been developed for several endoderm-derived cells, including hepatocytes, β-cells and intestinal cells. However, stomach lineage commitment from pluripotent stem cells has remained a challenge, and only antrum specification has been demonstrated. We established a method for stomach differentiation from embryonic stem cells by inducing mesenchymal Barx1, an essential gene for in vivo stomach specification from gut endoderm. Barx1-inducing culture conditions generated stomach primordium-like spheroids, which differentiated into mature stomach tissue cells in both the corpus and antrum by three-dimensional culture. This embryonic stem cell-derived stomach tissue (e-ST) shared a similar gene expression profile with adult stomach, and secreted pepsinogen as well as gastric acid. Furthermore, TGFA overexpression in e-ST caused hypertrophic mucus and gastric anacidity, which mimicked Ménétrier disease in vitro. Thus, in vitro stomach tissue derived from pluripotent stem cells mimics in vivo development and can be used for stomach disease models.

  6. Thalidomide induced early gene expression perturbations indicative of human embryopathy in mouse embryonic stem cells

    International Nuclear Information System (INIS)

    Gao, Xiugong; Sprando, Robert L.; Yourick, Jeffrey J.

    2015-01-01

    Developmental toxicity testing has traditionally relied on animal models which are costly, time consuming, and require the sacrifice of large numbers of animals. In addition, there are significant disparities between human beings and animals in their responses to chemicals. Thalidomide is a species-specific developmental toxicant that causes severe limb malformations in humans but not in mice. Here, we used microarrays to study transcriptomic changes induced by thalidomide in an in vitro model based on differentiation of mouse embryonic stem cells (mESCs). C57BL/6 mESCs were allowed to differentiate spontaneously and RNA was collected at 24, 48, and 72 h after exposure to 0.25 mM thalidomide. Global gene expression analysis using microarrays revealed hundreds of differentially expressed genes upon thalidomide exposure that were enriched in gene ontology (GO) terms and canonical pathways associated with embryonic development and differentiation. In addition, many genes were found to be involved in small GTPases-mediated signal transduction, heart development, and inflammatory responses, which coincide with clinical evidences and may represent critical embryotoxicities of thalidomide. These results demonstrate that transcriptomics in combination with mouse embryonic stem cell differentiation is a promising alternative model for developmental toxicity assessment. - Highlights: • Studied genomic changes in mouse embryonic stem cells upon thalidomide exposure • Identified gene expression changes that may represent thalidomide embryotoxicity • The toxicogenomic changes coincide well with known thalidomide clinical outcomes. • The mouse embryonic stem cell model is suitable for developmental toxicity testing. • The model has the potential for high-throughput screening of a multitude of compounds

  7. Thalidomide induced early gene expression perturbations indicative of human embryopathy in mouse embryonic stem cells

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Xiugong, E-mail: xiugong.gao@fda.hhs.gov; Sprando, Robert L.; Yourick, Jeffrey J.

    2015-08-15

    Developmental toxicity testing has traditionally relied on animal models which are costly, time consuming, and require the sacrifice of large numbers of animals. In addition, there are significant disparities between human beings and animals in their responses to chemicals. Thalidomide is a species-specific developmental toxicant that causes severe limb malformations in humans but not in mice. Here, we used microarrays to study transcriptomic changes induced by thalidomide in an in vitro model based on differentiation of mouse embryonic stem cells (mESCs). C57BL/6 mESCs were allowed to differentiate spontaneously and RNA was collected at 24, 48, and 72 h after exposure to 0.25 mM thalidomide. Global gene expression analysis using microarrays revealed hundreds of differentially expressed genes upon thalidomide exposure that were enriched in gene ontology (GO) terms and canonical pathways associated with embryonic development and differentiation. In addition, many genes were found to be involved in small GTPases-mediated signal transduction, heart development, and inflammatory responses, which coincide with clinical evidences and may represent critical embryotoxicities of thalidomide. These results demonstrate that transcriptomics in combination with mouse embryonic stem cell differentiation is a promising alternative model for developmental toxicity assessment. - Highlights: • Studied genomic changes in mouse embryonic stem cells upon thalidomide exposure • Identified gene expression changes that may represent thalidomide embryotoxicity • The toxicogenomic changes coincide well with known thalidomide clinical outcomes. • The mouse embryonic stem cell model is suitable for developmental toxicity testing. • The model has the potential for high-throughput screening of a multitude of compounds.

  8. Study on the immunity state of mouse exposed to mobile phone radiation during embryonic phase

    International Nuclear Information System (INIS)

    Pei Yinhui; Gao Hui

    2008-01-01

    Objective: To study the effect of mobile phone radiation on mouse which exposed to radiation during embryonic phase. Methods: Pregnant mice were exposed to mobile phone radiation. The mice's netrophile phage percentage and spleen lymphocyte transformation rate were detected respectively 2 months after birth. Results: The netrophile phage percentage of experimental mice was seemly the same as that of control group, and there was no significant difference (P>0.05), but the spleen transformation rate showed the diverse trend. Conclusion: The specific cellular immunity of mice, which ex- posed to mobile phone radiation during embryonic phase, was seen to be in a state of decreasement. (authors)

  9. Laser fusion of mouse embryonic cells and intra-embryonic fusion of blastomeres without affecting the embryo integrity.

    Science.gov (United States)

    Krivokharchenko, Alexander; Karmenyan, Artashes; Sarkisov, Oleg; Bader, Michael; Chiou, Arthur; Shakhbazyan, Avetik

    2012-01-01

    Manipulation with early mammalian embryos is the one of the most important approach to study preimplantation development. Artificial cell fusion is a research tool for various biotechnological experiments. However, the existing methods have various disadvantages, first of them impossibility to fuse selected cells within multicellular structures like mammalian preimplantation embryos. In our experiments we have successfully used high repetition rate picosecond near infrared laser beam for fusion of pairs of oocytes and oocytes with blastomeres. Fused cells looked morphologically normal and keep their ability for further divisions in vitro. We also fused two or three blastomeres inside four-cell mouse embryos. The presence of one, two or three nuclei in different blastomeres of the same early preimplantation mouse embryo was confirmed under UV-light after staining of DNA with the vital dye Hoechst-33342. The most of established embryos demonstrated high viability and developed in vitro to the blastocyst stage. We demonstrated for the first time the use of laser beam for the fusion of various embryonic cells of different size and of two or three blastomeres inside of four-cell mouse embryos without affecting the embryo's integrity and viability. These embryos with blastomeres of various ploidy maybe unique model for numerous purposes. Thus, we propose laser optical manipulation as a new tool for investigation of fundamental mechanisms of mammalian development.

  10. Mouse oocytes nucleoli rescue embryonic development of porcine enucleolated oocytes

    Czech Academy of Sciences Publication Activity Database

    Morovic, M.; Strejček, F.; Nakagawa, S.; Deshmukh, R.S.; Murin, M.; Benc, M.; Fulka, Helena; Kyogoku, H.; Pendovski, L.; Fulka, J.; Laurinčik, Jozef

    2017-01-01

    Roč. 25, č. 6 (2017), s. 675-685 ISSN 0967-1994 R&D Projects: GA MŠk EF15_003/0000460 Institutional support: RVO:68378050 ; RVO:67985904 Keywords : Embryo * Interspecies nucleolar transfer * Mouse * Nucleolus * Olcytes * Pig Subject RIV: EB - Genetics ; Molecular Biology OBOR OECD: Reproductive biology (medical aspects to be 3); Developmental biology (UZFG-Y) Impact factor: 1.053, year: 2016

  11. Combinatorial binding in human and mouse embryonic stem cells identifies conserved enhancers active in early embryonic development.

    Directory of Open Access Journals (Sweden)

    Jonathan Göke

    2011-12-01

    Full Text Available Transcription factors are proteins that regulate gene expression by binding to cis-regulatory sequences such as promoters and enhancers. In embryonic stem (ES cells, binding of the transcription factors OCT4, SOX2 and NANOG is essential to maintain the capacity of the cells to differentiate into any cell type of the developing embryo. It is known that transcription factors interact to regulate gene expression. In this study we show that combinatorial binding is strongly associated with co-localization of the transcriptional co-activator Mediator, H3K27ac and increased expression of nearby genes in embryonic stem cells. We observe that the same loci bound by Oct4, Nanog and Sox2 in ES cells frequently drive expression in early embryonic development. Comparison of mouse and human ES cells shows that less than 5% of individual binding events for OCT4, SOX2 and NANOG are shared between species. In contrast, about 15% of combinatorial binding events and even between 53% and 63% of combinatorial binding events at enhancers active in early development are conserved. Our analysis suggests that the combination of OCT4, SOX2 and NANOG binding is critical for transcription in ES cells and likely plays an important role for embryogenesis by binding at conserved early developmental enhancers. Our data suggests that the fast evolutionary rewiring of regulatory networks mainly affects individual binding events, whereas "gene regulatory hotspots" which are bound by multiple factors and active in multiple tissues throughout early development are under stronger evolutionary constraints.

  12. Pluripotent State Induction in Mouse Embryonic Fibroblast Using mRNAs of Reprogramming Factors

    Directory of Open Access Journals (Sweden)

    Ahmed Kamel El-Sayed

    2014-11-01

    Full Text Available Reprogramming of somatic cells has great potential to provide therapeutic treatments for a number of diseases as well as provide insight into mechanisms underlying early embryonic development. Improvement of induced Pluripotent Stem Cells (iPSCs generation through mRNA-based methods is currently an area of intense research. This approach provides a number of advantages over previously used methods such as DNA integration and insertional mutagenesis. Using transfection of specifically synthesized mRNAs of various pluripotency factors, we generated iPSCs from mouse embryonic fibroblast (MEF cells. The genetic, epigenetic and functional properties of the iPSCs were evaluated at different times during the reprogramming process. We successfully introduced synthesized mRNAs, which localized correctly inside the cells and exhibited efficient and stable translation into proteins. Our work demonstrated a robust up-regulation and a gradual promoter de-methylation of the pluripotency markers, including non-transfected factors such as Nanog, SSEA-1 (stage-specific embryonic antigen 1 and Rex-1 (ZFP-42, zinc finger protein 42. Using embryonic stem cells (ESCs conditions to culture the iPS cells resulted in formation of ES-like colonies after approximately 12 days with only five daily repeated transfections. The colonies were positive for alkaline phosphatase and pluripotency-specific markers associated with ESCs. This study revealed the ability of pluripotency induction and generation of mouse mRNA induced pluripotent stem cells (mRNA iPSCs using transfection of specifically synthesized mRNAs of various pluripotency factors into mouse embryonic fibroblast (MEF cells. These generated iPSCs exhibited molecular and functional properties similar to ESCs, which indicate that this method is an efficient and viable alternative to ESCs and can be used for further biological, developmental and therapeutic investigations.

  13. LASP-01: Distribution of Mouse Embryonic Stem Cells Expressing MicroRNAs | Frederick National Laboratory for Cancer Research

    Science.gov (United States)

    The Laboratory Animal Sciences Program manages the expansion, processing, and distribution of1,501 genetically engineered mouse embryonic stem cell (mESC) linesharboring conditional microRNA transgenes. The Laboratory Animal Sciences Prog

  14. Inference of Transcriptional Network for Pluripotency in Mouse Embryonic Stem Cells

    International Nuclear Information System (INIS)

    Aburatani, S

    2015-01-01

    In embryonic stem cells, various transcription factors (TFs) maintain pluripotency. To gain insights into the regulatory system controlling pluripotency, I inferred the regulatory relationships between the TFs expressed in ES cells. In this study, I applied a method based on structural equation modeling (SEM), combined with factor analysis, to 649 expression profiles of 19 TF genes measured in mouse Embryonic Stem Cells (ESCs). The factor analysis identified 19 TF genes that were regulated by several unmeasured factors. Since the known cell reprogramming TF genes (Pou5f1, Sox2 and Nanog) are regulated by different factors, each estimated factor is considered to be an input for signal transduction to control pluripotency in mouse ESCs. In the inferred network model, TF proteins were also arranged as unmeasured factors that control other TFs. The interpretation of the inferred network model revealed the regulatory mechanism for controlling pluripotency in ES cells

  15. Embryonic Lethality of Mitochondrial Pyruvate Carrier 1 Deficient Mouse Can Be Rescued by a Ketogenic Diet

    Science.gov (United States)

    Krznar, Petra; Hörl, Manuel; Ammar, Zeinab; Montessuit, Sylvie; Pierredon, Sandra; Zamboni, Nicola; Martinou, Jean-Claude

    2016-01-01

    Mitochondrial import of pyruvate by the mitochondrial pyruvate carrier (MPC) is a central step which links cytosolic and mitochondrial intermediary metabolism. To investigate the role of the MPC in mammalian physiology and development, we generated a mouse strain with complete loss of MPC1 expression. This resulted in embryonic lethality at around E13.5. Mouse embryonic fibroblasts (MEFs) derived from mutant mice displayed defective pyruvate-driven respiration as well as perturbed metabolic profiles, and both defects could be restored by reexpression of MPC1. Labeling experiments using 13C-labeled glucose and glutamine demonstrated that MPC deficiency causes increased glutaminolysis and reduced contribution of glucose-derived pyruvate to the TCA cycle. Morphological defects were observed in mutant embryonic brains, together with major alterations of their metabolome including lactic acidosis, diminished TCA cycle intermediates, energy deficit and a perturbed balance of neurotransmitters. Strikingly, these changes were reversed when the pregnant dams were fed a ketogenic diet, which provides acetyl-CoA directly to the TCA cycle and bypasses the need for a functional MPC. This allowed the normal gestation and development of MPC deficient pups, even though they all died within a few minutes post-delivery. This study establishes the MPC as a key player in regulating the metabolic state necessary for embryonic development, neurotransmitter balance and post-natal survival. PMID:27176894

  16. Mouse Rad9b is essential for embryonic development and promotes resistance to DNA damage

    Science.gov (United States)

    Leloup, Corinne; Hopkins, Kevin M.; Wang, Xiangyuan; Zhu, Aiping; Wolgemuth, Debra J.; Lieberman, Howard B.

    2010-01-01

    RAD9 participates in promoting resistance to DNA damage, cell cycle checkpoint control, DNA repair, apoptosis, embryogenesis, and regulation of transcription. A paralogue of RAD9 (named RAD9B) has been identified. To define the function of mouse Rad9b (Mrad9b), embryonic stem (ES) cells with a targeted gene deletion were constructed and used to generate Mrad9b mutant mice. Mrad9b−/− embryos are resorbed after E7.5 while some of the heterozygotes die between E12.5 and a few days after birth. Mrad9b is expressed in embryonic brain and Mrad9b+/− embryos exhibit abnormal neural tube closure. Mrad9b−/− mouse embryonic fibroblasts are not viable. Mrad9b−/− ES cells are more sensitive to gamma rays and mitomycin C than Mrad9b+/+ controls, but show normal gamma-ray-induced G2/M checkpoint control. There is no evidence of spontaneous genomic instability in Mrad9b−/− cells. Our findings thus indicate that Mrad9b is essential for embryonic development and mediates resistance to certain DNA damaging agents. PMID:20842695

  17. Live imaging of mitosis in the developing mouse embryonic cortex.

    Science.gov (United States)

    Pilaz, Louis-Jan; Silver, Debra L

    2014-06-04

    Although of short duration, mitosis is a complex and dynamic multi-step process fundamental for development of organs including the brain. In the developing cerebral cortex, abnormal mitosis of neural progenitors can cause defects in brain size and function. Hence, there is a critical need for tools to understand the mechanisms of neural progenitor mitosis. Cortical development in rodents is an outstanding model for studying this process. Neural progenitor mitosis is commonly examined in fixed brain sections. This protocol will describe in detail an approach for live imaging of mitosis in ex vivo embryonic brain slices. We will describe the critical steps for this procedure, which include: brain extraction, brain embedding, vibratome sectioning of brain slices, staining and culturing of slices, and time-lapse imaging. We will then demonstrate and describe in detail how to perform post-acquisition analysis of mitosis. We include representative results from this assay using the vital dye Syto11, transgenic mice (histone H2B-EGFP and centrin-EGFP), and in utero electroporation (mCherry-α-tubulin). We will discuss how this procedure can be best optimized and how it can be modified for study of genetic regulation of mitosis. Live imaging of mitosis in brain slices is a flexible approach to assess the impact of age, anatomy, and genetic perturbation in a controlled environment, and to generate a large amount of data with high temporal and spatial resolution. Hence this protocol will complement existing tools for analysis of neural progenitor mitosis.

  18. Characterization of Bovine 5′-flanking Region during Differentiation of Mouse Embryonic Stem Cells

    Directory of Open Access Journals (Sweden)

    Hye-Jeong Jang

    2015-12-01

    Full Text Available Embryonic stem cells (ESCs have been used as a powerful tool for research including gene manipulated animal models and the study of developmental gene regulation. Among the critical regulatory factors that maintain the pluripotency and self-renewal of undifferentiated ESCs, NANOG plays a very important role. Nevertheless, because pluripotency maintaining factors and specific markers for livestock ESCs have not yet been probed, few studies of the NANOG gene from domestic animals including bovine have been reported. Therefore, we chose mouse ESCs in order to understand and compare NANOG expression between bovine, human, and mouse during ESCs differentiation. We cloned a 600 bp (−420/+181 bovine NANOG 5′-flanking region, and tagged it with humanized recombinant green fluorescent protein (hrGFP as a tracing reporter. Very high GFP expression for bovine NANOG promoter was observed in the mouse ESC line. GFP expression was monitored upon ESC differentiation and was gradually reduced along with differentiation toward neurons and adipocyte cells. Activity of bovine NANOG (−420/+181 promoter was compared with already known mouse and human NANOG promoters in mouse ESC and they were likely to show a similar pattern of regulation. In conclusion, bovine NANOG 5-flanking region functions in mouse ES cells and has characteristics similar to those of mouse and human. These results suggest that bovine gene function studied in mouse ES cells should be evaluated and extrapolated for application to characterization of bovine ES cells.

  19. The phenotype of FancB-mutant mouse embryonic stem cells

    OpenAIRE

    Kim, Tae Moon; Ko, Jun Ho; Choi, Yong Jun; Hu, Lingchuan; Hasty, Paul

    2011-01-01

    Fanconi anemia (FA) is a rare autosomal recessive disease characterized by bone marrow failure, developmental defects and cancer. There are multiple FA genes that enable the repair of interstrand crosslinks (ICLs) in coordination with a variety of other DNA repair pathways in a way that is poorly understood. Here we present the phenotype of mouse embryonic stem (ES) cells mutated for FancB. We found FancB-mutant cells exhibited reduced cellular proliferation, hypersensitivity to the crosslink...

  20. Endogenous production of fibronectin is required for self-renewal of cultured mouse embryonic stem cells

    OpenAIRE

    Hunt, Geoffrey C.; Singh, Purva; Schwarzbauer, Jean E.

    2012-01-01

    Pluripotent cells are attached to the extracellular matrix (ECM) as they make cell fate decisions within the stem cell niche. Here we show that the ubiquitous ECM protein fibronectin is required for self-renewal decisions by cultured mouse embryonic stem (mES) cells. Undifferentiated mES cells produce fibronectin and assemble a fibrillar matrix. Increasing the level of substrate fibronectin increased cell spreading and integrin receptor signaling through focal adhesion kinase, while concomita...

  1. [Activation of nucleolar organizers during in vitro cultivation of mouse R1 embryonic stem cells].

    Science.gov (United States)

    Kunafina, E R; Chaplina, M V; Filiasova, E I; Gibanova, N V; Khodarovich, Iu M; Larionov, O A; Zatsepina, O V

    2005-01-01

    We studies the activities of ribosomal genes (nucleolus forming regions of chromosomes) at successive stages of cultivation of the mouse R1 embryonic stem cells. The total number and number of active nucleolar organizers were estimated by means of in situ hybridization with mouse rDNA probes and argentophilic staining of nucleolus forming chromosomes regions from the 16th until the 32nd passages. The data we obtained suggest that the total number of nucleolar organizers per metaphase plate was constant (as a rule, eight), while the mean number of active nucleolar organizers progressively increased from the early (16th) to the late (32nd) passages: 5.2 +/- 0.4 versus 7.4 +/- 0.9 argentophilic organizers per cell. Cell heterogeneity by the number of active nucleolar organizers also increased during the late passages. Taken together, these data suggest activation of DNA transcription and synthesis of ribosomes during cultivation of mouse R1 embryonic stem cells. Based on the experimental and published data, it has been proposed that activation of ribosomal genes correlates in time with a decreased capacity of embryonic stem cells for pluripotent differentiation.

  2. Rac1 modulates cardiomyocyte adhesion during mouse embryonic development

    Energy Technology Data Exchange (ETDEWEB)

    Abu-Issa, Radwan, E-mail: rabuissa@umich.edu

    2015-01-24

    Highlights: • Conditional knockout of Rac1 using Nkx2.5 Cre line is lethal at E13.5. • The myocardium of the mutant is thin and disorganized. • The phenotype is not due to cardiomyocyte low proliferation or apoptosis. • The phenotype is due to specific defect in cardiomyocyte adhesion. - Abstract: Rac1, a member of the Rho subfamily of small GTPases, is involved in morphogenesis and differentiation of many cell types. Here we define a role of Rac1 in cardiac development by specifically deleting Rac1 in the pre-cardiac mesoderm using the Nkx2.5-Cre transgenic driver line. Rac1-conditional knockout embryos initiate heart development normally until embryonic day 11.5 (E11.5); their cardiac mesoderm is specified, and the heart tube is formed and looped. However, by E12.5-E13.5 the mutant hearts start failing and embryos develop edema and hemorrhage which is probably the cause for the lethality observed soon after. The hearts of Rac1-cKO embryos exhibit disorganized and thin myocardial walls and defects in outflow tract alignment. No significant differences of cardiomyocyte death or proliferation were found between developing control and mutant embryos. To uncover the role of Rac1 in the heart, E11.5 primary heart cells were cultured and analyzed in vitro. Rac1-deficient cardiomyocytes were less spread, round and loosely attached to the substrate and to each other implying that Rac1-mediated signaling is required for appropriate cell–cell and/or cellmatrix adhesion during cardiac development.

  3. Rac1 modulates cardiomyocyte adhesion during mouse embryonic development

    International Nuclear Information System (INIS)

    Abu-Issa, Radwan

    2015-01-01

    Highlights: • Conditional knockout of Rac1 using Nkx2.5 Cre line is lethal at E13.5. • The myocardium of the mutant is thin and disorganized. • The phenotype is not due to cardiomyocyte low proliferation or apoptosis. • The phenotype is due to specific defect in cardiomyocyte adhesion. - Abstract: Rac1, a member of the Rho subfamily of small GTPases, is involved in morphogenesis and differentiation of many cell types. Here we define a role of Rac1 in cardiac development by specifically deleting Rac1 in the pre-cardiac mesoderm using the Nkx2.5-Cre transgenic driver line. Rac1-conditional knockout embryos initiate heart development normally until embryonic day 11.5 (E11.5); their cardiac mesoderm is specified, and the heart tube is formed and looped. However, by E12.5-E13.5 the mutant hearts start failing and embryos develop edema and hemorrhage which is probably the cause for the lethality observed soon after. The hearts of Rac1-cKO embryos exhibit disorganized and thin myocardial walls and defects in outflow tract alignment. No significant differences of cardiomyocyte death or proliferation were found between developing control and mutant embryos. To uncover the role of Rac1 in the heart, E11.5 primary heart cells were cultured and analyzed in vitro. Rac1-deficient cardiomyocytes were less spread, round and loosely attached to the substrate and to each other implying that Rac1-mediated signaling is required for appropriate cell–cell and/or cellmatrix adhesion during cardiac development

  4. Mouse androgenetic embryonic stem cells differentiated to multiple cell lineages in three embryonic germ layers in vitro.

    Science.gov (United States)

    Teramura, Takeshi; Onodera, Yuta; Murakami, Hideki; Ito, Syunsuke; Mihara, Toshihiro; Takehara, Toshiyuki; Kato, Hiromi; Mitani, Tasuku; Anzai, Masayuki; Matsumoto, Kazuya; Saeki, Kazuhiro; Fukuda, Kanji; Sagawa, Norimasa; Osoi, Yoshihiko

    2009-06-01

    The embryos of some rodents and primates can precede early development without the process of fertilization; however, they cease to develop after implantation because of restricted expressions of imprinting genes. Asexually developed embryos are classified into parthenote/gynogenote and androgenote by their genomic origins. Embryonic stem cells (ESCs) derived from asexual origins have also been reported. To date, ESCs derived from parthenogenetic embryos (PgESCs) have been established in some species, including humans, and the possibility to be alternative sources for autologous cell transplantation in regenerative medicine has been proposed. However, some developmental characteristics, which might be important for therapeutic applications, such as multiple differentiation capacity and transplantability of the ESCs of androgenetic origin (AgESCs) are uncertain. Here, we induced differentiation of mouse AgESCs and observed derivation of neural cells, cardiomyocytes and hepatocytes in vitro. Following differentiated embryoid body (EB) transplantation in various mouse strains including the strain of origin, we found that the EBs could engraft in theoretically MHC-matched strains. Our results indicate that AgESCs possess at least two important characteristics, multiple differentiation properties in vitro and transplantability after differentiation, and suggest that they can also serve as a source of histocompatible tissues for transplantation.

  5. Essential roles of BCCIP in mouse embryonic development and structural stability of chromosomes.

    Directory of Open Access Journals (Sweden)

    Huimei Lu

    2011-09-01

    Full Text Available BCCIP is a BRCA2- and CDKN1A(p21-interacting protein that has been implicated in the maintenance of genomic integrity. To understand the in vivo functions of BCCIP, we generated a conditional BCCIP knockdown transgenic mouse model using Cre-LoxP mediated RNA interference. The BCCIP knockdown embryos displayed impaired cellular proliferation and apoptosis at day E7.5. Consistent with these results, the in vitro proliferation of blastocysts and mouse embryonic fibroblasts (MEFs of BCCIP knockdown mice were impaired considerably. The BCCIP deficient mouse embryos die before E11.5 day. Deletion of the p53 gene could not rescue the embryonic lethality due to BCCIP deficiency, but partially rescues the growth delay of mouse embryonic fibroblasts in vitro. To further understand the cause of development and proliferation defects in BCCIP-deficient mice, MEFs were subjected to chromosome stability analysis. The BCCIP-deficient MEFs displayed significant spontaneous chromosome structural alterations associated with replication stress, including a 3.5-fold induction of chromatid breaks. Remarkably, the BCCIP-deficient MEFs had a ∼20-fold increase in sister chromatid union (SCU, yet the induction of sister chromatid exchanges (SCE was modestly at 1.5 fold. SCU is a unique type of chromatid aberration that may give rise to chromatin bridges between daughter nuclei in anaphase. In addition, the BCCIP-deficient MEFs have reduced repair of irradiation-induced DNA damage and reductions of Rad51 protein and nuclear foci. Our data suggest a unique function of BCCIP, not only in repair of DNA damage, but also in resolving stalled replication forks and prevention of replication stress. In addition, BCCIP deficiency causes excessive spontaneous chromatin bridges via the formation of SCU, which can subsequently impair chromosome segregations in mitosis and cell division.

  6. Ochratoxin A Inhibits Mouse Embryonic Development by Activating a Mitochondrion-Dependent Apoptotic Signaling Pathway

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    Yan-Der Hsuuw

    2013-01-01

    Full Text Available Ochratoxin A (OTA, a mycotoxin found in many foods worldwide, causes nephrotoxicity, hepatotoxicity, and immunotoxicity, both in vitro and in vivo. In the present study, we explored the cytotoxic effects exerted by OTA on the blastocyst stage of mouse embryos, on subsequent embryonic attachment, on outgrowth in vitro, and following in vivo implantation via embryo transfer. Mouse blastocysts were incubated with or without OTA (1, 5, or 10 μM for 24 h. Cell proliferation and growth were investigated using dual differential staining; apoptosis was measured using the terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL assay; and embryo implantation and post-implantation development were assessed by examination of in vitro growth and the outcome of in vivo embryo transfer, respectively. Blastocysts treated with 10 μM OTA displayed a significantly increased level of apoptosis and a reduction in total cell number. Interestingly, we observed no marked difference in implantation success rate between OTA-pretreated and control blastocysts either during in vitro embryonic development (following implantation in a fibronectin-coated culture dish or after in vivo embryo transfer. However, in vitro treatment with 10 μM OTA was associated with increased resorption of post-implantation embryos by the mouse uterus, and decreased fetal weight upon embryo transfer. Our results collectively indicate that in vitro exposure to OTA triggers apoptosis and retards early post-implantation development after transfer of embryos to host mice. In addition, OTA induces apoptosis-mediated injury of mouse blastocysts, via reactive oxygen species (ROS generation, and promotes mitochondrion-dependent apoptotic signaling processes that impair subsequent embryonic development.

  7. Flow-cytometric analysis of mouse embryonic stem cell lipofection using small and large DNA constructs.

    Science.gov (United States)

    McLenachan, Samuel; Sarsero, Joseph P; Ioannou, Panos A

    2007-06-01

    Using the lipofection reagent LipofectAMINE 2000 we have examined the delivery of plasmid DNA (5-200 kb) to mouse embryonic stem (mES) cells by flow cytometry. To follow the physical uptake of lipoplexes we labeled DNA molecules with the fluorescent dye TOTO-1. In parallel, expression of an EGFP reporter cassette in constructs of different sizes was used as a measure of nuclear delivery. The cellular uptake of DNA lipoplexes is dependent on the uptake competence of mES cells, but it is largely independent of DNA size. In contrast, nuclear delivery was reduced with increasing plasmid size. In addition, linear DNA is transfected with lower efficiency than circular DNA. Inefficient cytoplasmic trafficking appears to be the main limitation in the nonviral delivery of large DNA constructs to the nucleus of mES cells. Overcoming this limitation should greatly facilitate functional studies with large genomic fragments in embryonic stem cells.

  8. Metastable primordial germ cell-like state induced from mouse embryonic stem cells by Akt activation

    Energy Technology Data Exchange (ETDEWEB)

    Yamano, Noriko [Graduate School of Frontier Biosciences, Osaka University, 2-2 Yamada-oka, Suita, Osaka 565-0871 (Japan); Kimura, Tohru, E-mail: tkimura@patho.med.osaka-u.ac.jp [Department of Pathology, Medical School, Osaka University, 2-2 Yamada-oka, Suita, Osaka 565-0871 (Japan); Watanabe-Kushima, Shoko [Graduate School of Frontier Biosciences, Osaka University, 2-2 Yamada-oka, Suita, Osaka 565-0871 (Japan); Shinohara, Takashi [Department of Molecular Genetics, Graduate School of Medicine, Kyoto University, Kyoto 606-8501 (Japan); Nakano, Toru, E-mail: tnakano@patho.med.osaka-u.ac.jp [Graduate School of Frontier Biosciences, Osaka University, 2-2 Yamada-oka, Suita, Osaka 565-0871 (Japan); Department of Pathology, Medical School, Osaka University, 2-2 Yamada-oka, Suita, Osaka 565-0871 (Japan)

    2010-02-12

    Specification to primordial germ cells (PGCs) is mediated by mesoderm-induction signals during gastrulation. We found that Akt activation during in vitro mesodermal differentiation of embryonic stem cells (ESCs) generated self-renewing spheres with differentiation states between those of ESCs and PGCs. Essential regulators for PGC specification and their downstream germ cell-specific genes were expressed in the spheres, indicating that the sphere cells had commenced differentiation to the germ lineage. However, the spheres did not proceed to spermatogenesis after transplantation into testes. Sphere cell transfer to the original feeder-free ESC cultures resulted in chaotic differentiation. In contrast, when the spheres were cultured on mouse embryonic fibroblasts or in the presence of ERK-cascade and GSK3 inhibitors, reversion to the ESC-like state was observed. These results indicate that Akt signaling promotes a novel metastable and pluripotent state that is intermediate to those of ESCs and PGCs.

  9. In vitro generation of motor neuron precursors from mouse embryonic stem cells using mesoporous nanoparticles

    DEFF Research Database (Denmark)

    Garcia-Bennett, Alfonso E; König, Niclas; Abrahamsson, Ninnie

    2014-01-01

    nanoparticles could be effective for stem cell differentiation in vitro. Materials & methods: We used a mouse embryonic stem cell line expressing green fluorescent protein under the promoter for the MN-specific gene Hb9 to visualize the level of MN differentiation. The differentiation of stem cells......Aim: Stem cell-derived motor neurons (MNs) are utilized to develop replacement strategies for spinal cord disorders. Differentiation of embryonic stem cells into MN precursors involves factors and their repeated administration. We investigated if delivery of factors loaded into mesoporous...... was evaluated by expression of MN-specific transcription factors monitored by quantitative real-time PCR reactions and immunocytochemistry. Results: Mesoporous nanoparticles have strong affiliation to the embryoid bodies, penetrate inside the embryoid bodies and come in contact with differentiating cells...

  10. Mouse embryonic stem cell culture for generation of three-dimensional retinal and cortical tissues.

    Science.gov (United States)

    Eiraku, Mototsugu; Sasai, Yoshiki

    2011-12-15

    Generation of compound tissues with complex structures is a major challenge in cell biology. In this article, we describe a protocol for mouse embryonic stem cell (ESC) culture for in vitro generation of three-dimensional retinal tissue, comparing it with the culture protocol for cortical tissue generation. Dissociated ESCs are reaggregated in a 96-well plate with reduced cell-plate adhesion and cultured as floating aggregates. Retinal epithelium is efficiently generated when ESC aggregates are cultured in serum-free medium containing extracellular matrix proteins, spontaneously forming hemispherical vesicles and then progressively transforming into a shape reminiscent of the embryonic optic cup in 9-10 d. In long-term culture, the ESC-derived optic cup generates a fully stratified retinal tissue consisting of all major neural retinal components. In contrast, the cortical differentiation culture can be started without exogenous extracellular matrix proteins, and it generates stratified cortical epithelia consisting of four distinct layers in 13 d.

  11. Sertad1 encodes a novel transcriptional co-activator of SMAD1 in mouse embryonic hearts

    Energy Technology Data Exchange (ETDEWEB)

    Peng, Yin [Department of Genetics, The University of Alabama at Birmingham, Birmingham, AL 35294 (United States); Zhao, Shaomin [Department of Genetics, The University of Alabama at Birmingham, Birmingham, AL 35294 (United States); School of Traditional Chinese Medicine, Capital Medical University, Beijing 100069 (China); Song, Langying [Department of Genetics, The University of Alabama at Birmingham, Birmingham, AL 35294 (United States); Wang, Manyuan [School of Traditional Chinese Medicine, Capital Medical University, Beijing 100069 (China); Jiao, Kai, E-mail: kjiao@uab.edu [Department of Genetics, The University of Alabama at Birmingham, Birmingham, AL 35294 (United States)

    2013-11-29

    Highlights: •SERTAD1 interacts with SMAD1. •Sertad1 is expressed in mouse embryonic hearts. •SERTAD1 is localized in both cytoplasm and nucleus of cardiomyocytes. •SERTAD1 enhances expression of BMP target cardiogenic genes as a SMAD1 co-activator. -- Abstract: Despite considerable advances in surgical repairing procedures, congenital heart diseases (CHDs) remain the leading noninfectious cause of infant morbidity and mortality. Understanding the molecular/genetic mechanisms underlying normal cardiogenesis will provide essential information for the development of novel diagnostic and therapeutic strategies against CHDs. BMP signaling plays complex roles in multiple cardiogenic processes in mammals. SMAD1 is a canonical nuclear mediator of BMP signaling, the activity of which is critically regulated through its interaction partners. We screened a mouse embryonic heart yeast two-hybrid library using Smad1 as bait and identified SERTAD1 as a novel interaction partner of SMAD1. SERTAD1 contains multiple potential functional domains, including two partially overlapping transactivation domains at the C terminus. The SERTAD1-SMAD1 interaction in vitro and in mammalian cells was further confirmed through biochemical assays. The expression of Sertad1 in developing hearts was demonstrated using RT-PCR, western blotting and in situ hybridization analyses. We also showed that SERTAD1 was localized in both the cytoplasm and nucleus of immortalized cardiomyocytes and primary embryonic cardiomyocyte cultures. The overexpression of SERTAD1 in cardiomyocytes not only enhanced the activity of two BMP reporters in a dose-dependent manner but also increased the expression of several known BMP/SMAD regulatory targets. Therefore, these data suggest that SERTAD1 acts as a SMAD1 transcriptional co-activator to promote the expression of BMP target genes during mouse cardiogenesis.

  12. Msx-2 expression and glucocorticoid-induced overexpression in embryonic mouse submandibular glands.

    Science.gov (United States)

    Jaskoll, T; Luo, W; Snead, M L

    1998-01-01

    It is well known that the process of branching morphogenesis requires epithelial-mesenchymal interactions. One outstanding model for the study of tissue interactions during branching morphogenesis is the embryonic mouse submandibular gland (SMG). Although it has been clearly demonstrated that the branching pattern is dependent on interactions between the epithelium and the surrounding mesenchyme, little is known about the molecular mechanism underlying the branching process. One group of transcription factors that likely participates in the control of epithelial-mesenchymal inductive interactions are the Msx-class of homeodomain-containing proteins. In this paper, we focus on Msx-2 because its developmental expression is correlated with inductive interactions, suggesting that Msx-2 may play a functional role during cell-cell interactions. We demonstrate the expression of Msx-2 mRNA and protein to be primarily in the branching epithelia with progressive embryonic (E13 to E15) SMG development and, to a lesser extent, in the mesenchyme. We also show that Msx-2 is expressed by embryonic SMG primordia cultured under defined conditions. In addition, to begin to delineate a functional role for Msx-2, we employed an experimental strategy by using exogenous glucocorticoid (CORT) treatment of embryonic SMGs in vitro and in vivo to significantly enhance branching morphogenesis and evaluate the effect of CORT treatment on embryonic SMG Msx-2 expression. A marked increase in Msx-2 transcripts and protein is detected with in vitro and in vivo CORT treatment. Our studies indicate that one mechanism of CORT regulation of salivary gland morphogenesis is likely through the modulation of Msx-2 gene expression.

  13. Two pore channel 2 differentially modulates neural differentiation of mouse embryonic stem cells.

    Directory of Open Access Journals (Sweden)

    Zhe-Hao Zhang

    Full Text Available Nicotinic acid adenine dinucleotide phosphate (NAADP is an endogenous Ca(2+ mobilizing nucleotide presented in various species. NAADP mobilizes Ca(2+ from acidic organelles through two pore channel 2 (TPC2 in many cell types and it has been previously shown that NAADP can potently induce neuronal differentiation in PC12 cells. Here we examined the role of TPC2 signaling in the neural differentiation of mouse embryonic stem (ES cells. We found that the expression of TPC2 was markedly decreased during the initial ES cell entry into neural progenitors, and the levels of TPC2 gradually rebounded during the late stages of neurogenesis. Correspondingly, TPC2 knockdown accelerated mouse ES cell differentiation into neural progenitors but inhibited these neural progenitors from committing to neurons. Overexpression of TPC2, on the other hand, inhibited mouse ES cell from entering the early neural lineage. Interestingly, TPC2 knockdown had no effect on the differentiation of astrocytes and oligodendrocytes of mouse ES cells. Taken together, our data indicate that TPC2 signaling plays a temporal and differential role in modulating the neural lineage entry of mouse ES cells, in that TPC2 signaling inhibits ES cell entry to early neural progenitors, but is required for late neuronal differentiation.

  14. Data on the potential impact of food supplements on the growth of mouse embryonic stem cells.

    Science.gov (United States)

    Correia, Marcelo; Sousa, Maria I; Rodrigues, Ana S; Perestrelo, Tânia; Pereira, Sandro L; Ribeiro, Marcelo F; Ramalho-Santos, João

    2016-06-01

    The use of new compounds as dietary supplements is increasing, but little is known in terms of possible consequences of their use. Pluripotent stem cells are a promising research tool for citotoxicological research for evaluation of proliferation, cell death, pluripotency and differentiation. Using the mouse embryonic stem cell (mESC) model, we present data on three different compounds that have been proposed as new potential supplements for co-adjuvant disease treatments: kaempferol, berberine and Tauroursodeoxycholic acid (TUDCA). Cell number and viability were monitored following treatment with increased concentrations of each drug in pluripotent culture conditions.

  15. BLM has early and late functions in homologous recombination repair in mouse embryonic stem cells

    DEFF Research Database (Denmark)

    Chu, W K; Hanada, K; Kanaar, R

    2010-01-01

    function of BLM remains unclear. Multiple roles have been proposed for BLM in the homologous recombination (HR) repair pathway, including 'early' functions, such as the stimulation of resection of DNA double-strand break ends or displacement of the invading strand of DNA displacement loops, and 'late......' roles, such as dissolution of double Holliday junctions. However, most of the evidence for these putative roles comes from in vitro biochemical data. In this study, we report the characterization of mouse embryonic stem cells with disruption of Blm and/or Rad54 genes. We show that Blm has roles both...

  16. Depletion of Tcf3 and Lef1 maintains mouse embryonic stem cell self-renewal

    OpenAIRE

    Ye, Shoudong; Zhang, Tao; Tong, Chang; Zhou, Xingliang; He, Kan; Ban, Qian; Liu, Dahai; Ying, Qi-Long

    2017-01-01

    ABSTRACT Mouse and rat embryonic stem cell (ESC) self-renewal can be maintained by dual inhibition of glycogen synthase kinase 3 (GSK3) and mitogen-activated protein kinase kinase (MEK). Inhibition of GSK3 promotes ESC self-renewal by abrogating T-cell factor 3 (TCF3)-mediated repression of the pluripotency network. How inhibition of MEK mediates ESC self-renewal, however, remains largely unknown. Here, we show that inhibition of MEK can significantly suppress lymphoid enhancer factor 1 (LEF1...

  17. Refined mapping of a quantitative trait locus on chromosome 1 responsible for mouse embryonic death.

    Directory of Open Access Journals (Sweden)

    Magalie Vatin

    Full Text Available Recurrent spontaneous abortion (RSA is defined as the loss of three or more consecutive pregnancies during the first trimester of embryonic intrauterine development. This kind of human infertility is frequent among the general population since it affects 1 to 5% of women. In half of the cases the etiology remains unelucidated. In the present study, we used interspecific recombinant congenic mouse strains (IRCS in the aim to identify genes responsible for embryonic lethality. Applying a cartographic approach using a genotype/phenotype association, we identified a minimal QTL region, of about 6 Mb on chromosome 1, responsible for a high rate of embryonic death (∼30%. Genetic analysis suggests that the observed phenotype is linked to uterine dysfunction. Transcriptomic analysis of the uterine tissue revealed a preferential deregulation of genes of this region compared to the rest of the genome. Some genes from the QTL region are associated with VEGF signaling, mTOR signaling and ubiquitine/proteasome-protein degradation pathways. This work may contribute to elucidate the molecular basis of a multifactorial and complex human disorder as RSA.

  18. Rhein Induces Oxidative Stress and Apoptosis in Mouse Blastocysts and Has Immunotoxic Effects during Embryonic Development

    Directory of Open Access Journals (Sweden)

    Chien-Hsun Huang

    2017-09-01

    Full Text Available Rhein, a glucoside chemical compound found in a traditional Chinese medicine derived from the roots of rhubarb, induces cell apoptosis and is considered to have high potential as an antitumor drug. Several previous studies showed that rhein can inhibit cell proliferation and trigger mitochondria-related or endoplasmic reticulum (ER stress-dependent apoptotic processes. However, the side effects of rhein on pre- and post-implantation embryonic development remain unclear. Here, we show that rhein has cytotoxic effects on blastocyst-stage mouse embryos and induces oxidative stress and immunotoxicity in mouse fetuses. Blastocysts incubated with 5–20 μM rhein showed significant cell apoptosis, as well as decreases in their inner cell mass cell numbers and total cell numbers. An in vitro development assay showed that rhein affected the developmental potentials of both pre- and post-implantation embryos. Incubation of blastocysts with 5–20 μM rhein was associated with increased resorption of post-implantation embryos and decreased fetal weight in an embryo transfer assay. Importantly, in an in vivo model, intravenous injection of dams with rhein (1, 3, and 5 mg/kg body weight/day for four days resulted in apoptosis of blastocyst-stage embryos, early embryonic developmental injury, and decreased fetal weight. Intravenous injection of dams with 5 mg/kg body weight/day rhein significantly increased the total reactive oxygen species (ROS content of fetuses and the transcription levels of antioxidant proteins in fetal livers. Additional work showed that rhein induced apoptosis through ROS generation, and that prevention of apoptotic processes effectively rescued the rhein-induced injury effects on embryonic development. Finally, the transcription levels of the innate-immunity related genes, CXCL1, IL-1 β and IL-8, were down-regulated in the fetuses of dams that received intravenous injections of rhein. These results collectively show that rhein has

  19. UTX and UTY demonstrate histone demethylase-independent function in mouse embryonic development.

    Directory of Open Access Journals (Sweden)

    Karl B Shpargel

    2012-09-01

    Full Text Available UTX (KDM6A and UTY are homologous X and Y chromosome members of the Histone H3 Lysine 27 (H3K27 demethylase gene family. UTX can demethylate H3K27; however, in vitro assays suggest that human UTY has lost enzymatic activity due to sequence divergence. We produced mouse mutations in both Utx and Uty. Homozygous Utx mutant female embryos are mid-gestational lethal with defects in neural tube, yolk sac, and cardiac development. We demonstrate that mouse UTY is devoid of in vivo demethylase activity, so hemizygous X(Utx- Y(+ mutant male embryos should phenocopy homozygous X(Utx- X(Utx- females. However, X(Utx- Y(+ mutant male embryos develop to term; although runted, approximately 25% survive postnatally reaching adulthood. Hemizygous X(+ Y(Uty- mutant males are viable. In contrast, compound hemizygous X(Utx- Y(Uty- males phenocopy homozygous X(Utx- X(Utx- females. Therefore, despite divergence of UTX and UTY in catalyzing H3K27 demethylation, they maintain functional redundancy during embryonic development. Our data suggest that UTX and UTY are able to regulate gene activity through demethylase independent mechanisms. We conclude that UTX H3K27 demethylation is non-essential for embryonic viability.

  20. Systematic identification of cis-regulatory sequences active in mouse and human embryonic stem cells.

    Directory of Open Access Journals (Sweden)

    Marica Grskovic

    2007-08-01

    Full Text Available Understanding the transcriptional regulation of pluripotent cells is of fundamental interest and will greatly inform efforts aimed at directing differentiation of embryonic stem (ES cells or reprogramming somatic cells. We first analyzed the transcriptional profiles of mouse ES cells and primordial germ cells and identified genes upregulated in pluripotent cells both in vitro and in vivo. These genes are enriched for roles in transcription, chromatin remodeling, cell cycle, and DNA repair. We developed a novel computational algorithm, CompMoby, which combines analyses of sequences both aligned and non-aligned between different genomes with a probabilistic segmentation model to systematically predict short DNA motifs that regulate gene expression. CompMoby was used to identify conserved overrepresented motifs in genes upregulated in pluripotent cells. We show that the motifs are preferentially active in undifferentiated mouse ES and embryonic germ cells in a sequence-specific manner, and that they can act as enhancers in the context of an endogenous promoter. Importantly, the activity of the motifs is conserved in human ES cells. We further show that the transcription factor NF-Y specifically binds to one of the motifs, is differentially expressed during ES cell differentiation, and is required for ES cell proliferation. This study provides novel insights into the transcriptional regulatory networks of pluripotent cells. Our results suggest that this systematic approach can be broadly applied to understanding transcriptional networks in mammalian species.

  1. Redundant role of protein kinase C delta and epsilon during mouse embryonic development.

    Directory of Open Access Journals (Sweden)

    Sergio Carracedo

    Full Text Available Protein Kinase C delta and epsilon are mediators of important cellular events, such as cell proliferation, migration or apoptosis. The formation of blood vessels, i.e., vasculo- and angiogenesis, is a process where these isoforms have also been shown to participate. However, mice deficient in either Protein Kinase C delta or epsilon are viable and therefore their individual contribution to the formation of the vasculature appeared so far dispensable. In this study, we show that double null mutation of Protein Kinase C delta and epsilon causes embryonic lethality at approximately E9.5. At this stage, whole mount staining of the endothelial marker CD31 in double null embryos revealed defective blood vessel formation. Moreover, culture of double deficient mouse allantois showed impaired endothelial cell organization, and analyses of double deficient embryo sections showed dilated vessels, decreased endothelial-specific adherent junctions, and decreased contact of endothelial cells with mural cells. Protein kinase C delta and epsilon also appeared essential for vascular smooth muscle cell differentiation, since α-smooth muscle actin, a classical marker for vascular smooth muscle cells, was almost undetectable in double deficient embryonic aorta at E9.5. Subsequent qPCR analyses showed decreased VE-cadherin, Vegfr2, Cd31, Cdh2, Ets1, and Fli-1, among other angiogenesis related transcripts in double deficient embryos. Taken together, these data suggest for the first time an in vivo redundant role between members of the novel Protein Kinase C subfamily that allows for mutual compensation during mouse embryonic development, with vasculogenesis/angiogenesis as an obvious common function of these two Protein Kinase Cs. Protein Kinase C delta and epsilon might therefore be useful targets for inhibiting vasculo- and/or angiogenesis.

  2. Contribution of Mouse Embryonic Stem Cells and Induced Pluripotent Stem Cells to Chimeras through Injection and Coculture of Embryos

    OpenAIRE

    Guo, Jitong; Wu, Baojiang; Li, Shuyu; Bao, Siqin; Zhao, Lixia; Hu, Shuxiang; Sun, Wei; Su, Jie; Dai, Yanfeng; Li, Xihe

    2014-01-01

    Blastocyst injection and morula aggregation are commonly used to evaluate stem cell pluripotency based on chimeric contribution of the stem cells. To assess the protocols for generating chimeras from stem cells, 8-cell mouse embryos were either injected or cocultured with mouse embryonic stem cells and induced pluripotent stem cells, respectively. Although a significantly higher chimera rate resulted from blastocyst injection, the highest germline contribution resulted from injection of 8-cel...

  3. Symmetry breaking, germ layer specification and axial organisation in aggregates of mouse embryonic stem cells.

    Science.gov (United States)

    van den Brink, Susanne C; Baillie-Johnson, Peter; Balayo, Tina; Hadjantonakis, Anna-Katerina; Nowotschin, Sonja; Turner, David A; Martinez Arias, Alfonso

    2014-11-01

    Mouse embryonic stem cells (mESCs) are clonal populations derived from preimplantation mouse embryos that can be propagated in vitro and, when placed into blastocysts, contribute to all tissues of the embryo and integrate into the normal morphogenetic processes, i.e. they are pluripotent. However, although they can be steered to differentiate in vitro into all cell types of the organism, they cannot organise themselves into structures that resemble embryos. When aggregated into embryoid bodies they develop disorganised masses of different cell types with little spatial coherence. An exception to this rule is the emergence of retinas and anterior cortex-like structures under minimal culture conditions. These structures emerge from the cultures without any axial organisation. Here, we report that small aggregates of mESCs, of about 300 cells, self-organise into polarised structures that exhibit collective behaviours reminiscent of those that cells exhibit in early mouse embryos, including symmetry breaking, axial organisation, germ layer specification and cell behaviour, as well as axis elongation. The responses are signal specific and uncouple processes that in the embryo are tightly associated, such as specification of the anteroposterior axis and anterior neural development, or endoderm specification and axial elongation. We discuss the meaning and implications of these observations and the potential uses of these structures which, because of their behaviour, we suggest to call 'gastruloids'. © 2014. Published by The Company of Biologists Ltd.

  4. Overproduction of Upper-Layer Neurons in the Neocortex Leads to Autism-like Features in Mice

    Directory of Open Access Journals (Sweden)

    Wei-Qun Fang

    2014-12-01

    Full Text Available Summary: The functional integrity of the neocortex depends upon proper numbers of excitatory and inhibitory neurons; however, the consequences of dysregulated neuronal production during the development of the neocortex are unclear. As excess cortical neurons are linked to the neurodevelopmental disorder autism, we investigated whether the overproduction of neurons leads to neocortical malformation and malfunction in mice. We experimentally increased the number of pyramidal neurons in the upper neocortical layers by using the small molecule XAV939 to expand the intermediate progenitor population. The resultant overpopulation of neurons perturbs development of dendrites and spines of excitatory neurons and alters the laminar distribution of interneurons. Furthermore, these phenotypic changes are accompanied by dysregulated excitatory and inhibitory synaptic connection and balance. Importantly, these mice exhibit behavioral abnormalities resembling those of human autism. Thus, our findings collectively suggest a causal relationship between neuronal overproduction and autism-like features, providing developmental insights into the etiology of autism. : Fang et al. generated a mouse model with excessive excitatory neurons in the neocortex by manipulating embryonic neurogenesis. Overproduction of neurons results in autism-like anatomical and behavioral features. These findings suggest a causal relationship between overproduction of neurons and cortical malfunction and provide developmental insights into the etiology of autism.

  5. Evaluation of an adherent mouse embryonic stem cell in vitro assay to predict developmental toxicity of ToxCast chemicals.

    Science.gov (United States)

    The potential for most environmental chemicals to produce developmental toxicity is unknown. Mouse embryonic stem cell (mESC) assays are an alternative in vitro model to assess chemicals. The chemical space evaluated using mESC and compared to in vivo is limited. We used an adher...

  6. Developing predictions of in vivo developmental toxicity of ToxCast chemicals using mouse embryonic stem cells.

    Science.gov (United States)

    Developing predictions of in vivo developmental toxicity of ToxCast chemicals using mouse embryonic stem cells S. Hunter, M. Rosen, M. Hoopes, H. Nichols, S. Jeffay, K. Chandler1, Integrated Systems Toxicology Division, National Health and Environmental Effects Research Labor...

  7. A vector-based system for the differentiation of mouse embryonic stem cells toward germ-line cells

    Directory of Open Access Journals (Sweden)

    Reza Ebrahimzadeh-Vesal

    2014-08-01

    Conclusion: In this study, we demonstrated the in vitro generation of mouse embryonic stem cells to germ cells by using a backbone vector containing the fusion gene Stra8-EGFP. The Stra8 gene is a retinoic acid-responsive protein and is able to regulate meiotic initiation.

  8. Exogenous transforming growth factor-β1 enhances smooth muscle differentiation in embryonic mouse jejunal explants.

    Science.gov (United States)

    Coletta, Riccardo; Roberts, Neil A; Randles, Michael J; Morabito, Antonino; Woolf, Adrian S

    2017-01-13

    An ex vivo experimental strategy that replicates in vivo intestinal development would in theory provide an accessible setting with which to study normal and dysmorphic gut biology. The current authors recently described a system in which mouse embryonic jejunal segments were explanted onto semipermeable platforms and fed with chemically defined serum-free media. Over 3 days in organ culture, explants formed villi and they began to undergo spontaneous peristalsis. As defined in the current study, the wall of the explanted gut failed to form a robust longitudinal smooth muscle (SM) layer as it would do in vivo over the same time period. Given the role of transforming growth factor β1 (TGFβ1) in SM differentiation in other organs, it was hypothesized that exogenous TGFβ1 would enhance SM differentiation in these explants. In vivo, TGFβ receptors I and II were both detected in embryonic longitudinal jejunal SM cells and, in organ culture, exogenous TGFβ1 induced robust differentiation of longitudinal SM. Microarray profiling showed that TGFβ1 increased SM specific transcripts in a dose dependent manner. TGFβ1 proteins were detected in amniotic fluid at a time when the intestine was physiologically herniated. By analogy with the requirement for exogenous TGFβ1 for SM differentiation in organ culture, the TGFβ1 protein that was demonstrated to be present in the amniotic fluid may enhance intestinal development when it is physiologically herniated in early gestation. Future studies of embryonic intestinal cultures should include TGFβ1 in the defined media to produce a more faithful model of in vivo muscle differentiation. Copyright © 2017 The Authors Journal of Tissue Engineering and Regenerative Medicine Published by John Wiley & Sons, Ltd. Copyright © 2017 The Authors Journal of Tissue Engineering and Regenerative Medicine Published by John Wiley & Sons, Ltd.

  9. Gene expression analysis of mouse embryonic stem cells following levitation in an ultrasound standing wave trap.

    Science.gov (United States)

    Bazou, Despina; Kearney, Roisin; Mansergh, Fiona; Bourdon, Celine; Farrar, Jane; Wride, Michael

    2011-02-01

    In the present paper, gene expression analysis of mouse embryonic stem (ES) cells levitated in a novel ultrasound standing wave trap (USWT) (Bazou et al. 2005a) at variable acoustic pressures (0.08-0.85 MPa) and times (5-60 min) was performed. Our results showed that levitation of ES cells at the highest employed acoustic pressure for 60 min does not modify gene expression and cells maintain their pluripotency. Embryoid bodies (EBs) also expressed the early and late neural differentiation markers, which were also unaffected by the acoustic field. Our results suggest that the ultrasound trap microenvironment is minimally invasive as the biologic consequences of ES cell replication and EB differentiation proceed without significantly affecting gene expression. The technique holds great promise in safe cell manipulation techniques for a variety of applications including tissue engineering and regenerative medicine. Copyright © 2011 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  10. The phenotype of FancB-mutant mouse embryonic stem cells

    International Nuclear Information System (INIS)

    Kim, Tae Moon; Ko, Jun Ho; Choi, Yong Jun; Hu Lingchuan; Hasty, Paul

    2011-01-01

    Fanconi anemia (FA) is a rare autosomal recessive disease characterized by bone marrow failure, developmental defects and cancer. There are multiple FA genes that enable the repair of interstrand crosslinks (ICLs) in coordination with a variety of other DNA repair pathways in a way that is poorly understood. Here we present the phenotype of mouse embryonic stem (ES) cells mutated for FancB. We found FancB-mutant cells exhibited reduced cellular proliferation, hypersensitivity to the crosslinking agent mitomycin C (MMC), increased spontaneous and MMC-induced chromosomal abnormalities, reduced spontaneous sister chromatid exchanges (SCEs), reduced gene targeting, reduced MMC-induced Rad51 foci and absent MMC-induced FancD2 foci. Since FancB is on the X chromosome and since ES cells are typically XY, FancB is an excellent target for an epistatic analysis to elucidate FA's role in ICL repair.

  11. Isolation and characterization of node/notochord-like cells from mouse embryonic stem cells

    DEFF Research Database (Denmark)

    Winzi, Maria K.; Hyttel, Poul; Dale, Jacqueline Kim

    2011-01-01

    The homeobox gene Noto is expressed in the node and its derivative the notochord. Here we use a targeted Noto-GFP reporter to isolate and characterize node/notochord-like cells derived from mouse embryonic stem cells. We find very few Noto-expressing cells after spontaneous differentiation. However......, the number of Noto-expressing cells was increased when using Activin A to induce a Foxa2- and Brachyury-expressing progenitor population, whose further differentiation into Noto-expressing cells was improved by simultaneous inhibition of BMP, Wnt, and retinoic acid signaling. Noto-GFP(+) cells expressed...... the node/notochord markers Noto, Foxa2, Shh, Noggin, Chordin, Foxj1, and Brachyury; showed a vacuolarization characteristic of notochord cells; and can integrate into midline structures when grafted into Hensen's node of gastrulating chicken embryos. The ability to generate node/notochord-like cells...

  12. Single-Step Generation of Conditional Knockout Mouse Embryonic Stem Cells

    Directory of Open Access Journals (Sweden)

    Matyas Flemr

    2015-07-01

    Full Text Available Induction of double-strand DNA breaks (DSBs by engineered nucleases, such as CRISPR/Cas9 or transcription activator-like effector nucleases (TALENs, stimulates knockin of exogenous DNA fragments via homologous recombination (HR. However, the knockin efficiencies reported so far have not allowed more complex in vitro genome modifications such as, for instance, simultaneous integration of a DNA fragment at two distinct genomic sites. We developed a reporter system to enrich for cells with engineered nuclease-assisted HR events. Using this system in mouse embryonic stem cells (mESCs, we achieve single-step biallelic and seamless integration of two loxP sites for Cre recombinase-mediated inducible gene knockout, as well as biallelic endogenous gene tagging with high efficiency. Our approach reduces the time and resources required for conditional knockout mESC generation dramatically.

  13. Dissecting Transcriptional Heterogeneity in Pluripotency: Single Cell Analysis of Mouse Embryonic Stem Cells.

    Science.gov (United States)

    Guedes, Ana M V; Henrique, Domingos; Abranches, Elsa

    2016-01-01

    Mouse Embryonic Stem cells (mESCs) show heterogeneous and dynamic expression of important pluripotency regulatory factors. Single-cell analysis has revealed the existence of cell-to-cell variability in the expression of individual genes in mESCs. Understanding how these heterogeneities are regulated and what their functional consequences are is crucial to obtain a more comprehensive view of the pluripotent state.In this chapter we describe how to analyze transcriptional heterogeneity by monitoring gene expression of Nanog, Oct4, and Sox2, using single-molecule RNA FISH in single mESCs grown in different cell culture medium. We describe in detail all the steps involved in the protocol, from RNA detection to image acquisition and processing, as well as exploratory data analysis.

  14. Isolation and characterization of node/notochord-like cells from mouse embryonic stem cells.

    Science.gov (United States)

    Winzi, Maria K; Hyttel, Poul; Dale, Jacqueline Kim; Serup, Palle

    2011-11-01

    The homeobox gene Noto is expressed in the node and its derivative the notochord. Here we use a targeted Noto-GFP reporter to isolate and characterize node/notochord-like cells derived from mouse embryonic stem cells. We find very few Noto-expressing cells after spontaneous differentiation. However, the number of Noto-expressing cells was increased when using Activin A to induce a Foxa2- and Brachyury-expressing progenitor population, whose further differentiation into Noto-expressing cells was improved by simultaneous inhibition of BMP, Wnt, and retinoic acid signaling. Noto-GFP(+) cells expressed the node/notochord markers Noto, Foxa2, Shh, Noggin, Chordin, Foxj1, and Brachyury; showed a vacuolarization characteristic of notochord cells; and can integrate into midline structures when grafted into Hensen's node of gastrulating chicken embryos. The ability to generate node/notochord-like cells in vitro will aid the biochemical characterization of these developmentally important structures.

  15. The orphan adhesion-GPCR GPR126 is required for embryonic development in the mouse.

    Directory of Open Access Journals (Sweden)

    Helen Waller-Evans

    2010-11-01

    Full Text Available Adhesion-GPCRs provide essential cell-cell and cell-matrix interactions in development, and have been implicated in inherited human diseases like Usher Syndrome and bilateral frontoparietal polymicrogyria. They are the second largest subfamily of seven-transmembrane spanning proteins in vertebrates, but the function of most of these receptors is still not understood. The orphan Adhesion-GPCR GPR126 has recently been shown to play an essential role in the myelination of peripheral nerves in zebrafish. In parallel, whole-genome association studies have implicated variation at the GPR126 locus as a determinant of body height in the human population. The physiological function of GPR126 in mammals is still unknown. We describe a targeted mutation of GPR126 in the mouse, and show that GPR126 is required for embryonic viability and cardiovascular development.

  16. The phenotype of FancB-mutant mouse embryonic stem cells

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Tae Moon; Ko, Jun Ho; Choi, Yong Jun; Hu Lingchuan [Department of Molecular Medicine and Institute of Biotechnology, University of Texas Health Science Center at San Antonio, 15355 Lambda Drive, San Antonio, TX 78245 (United States); Hasty, Paul, E-mail: hastye@uthscsa.edu [Department of Molecular Medicine and Institute of Biotechnology, University of Texas Health Science Center at San Antonio, 15355 Lambda Drive, San Antonio, TX 78245 (United States)

    2011-07-01

    Fanconi anemia (FA) is a rare autosomal recessive disease characterized by bone marrow failure, developmental defects and cancer. There are multiple FA genes that enable the repair of interstrand crosslinks (ICLs) in coordination with a variety of other DNA repair pathways in a way that is poorly understood. Here we present the phenotype of mouse embryonic stem (ES) cells mutated for FancB. We found FancB-mutant cells exhibited reduced cellular proliferation, hypersensitivity to the crosslinking agent mitomycin C (MMC), increased spontaneous and MMC-induced chromosomal abnormalities, reduced spontaneous sister chromatid exchanges (SCEs), reduced gene targeting, reduced MMC-induced Rad51 foci and absent MMC-induced FancD2 foci. Since FancB is on the X chromosome and since ES cells are typically XY, FancB is an excellent target for an epistatic analysis to elucidate FA's role in ICL repair.

  17. Chondroitin Sulfate Is Indispensable for Pluripotency and Differentiation of Mouse Embryonic Stem Cells

    Science.gov (United States)

    Izumikawa, Tomomi; Sato, Ban; Kitagawa, Hiroshi

    2014-01-01

    Chondroitin sulfate (CS) proteoglycans are present on the surfaces of virtually all cells and in the extracellular matrix and are required for cytokinesis at early developmental stages. Studies have shown that heparan sulfate (HS) is essential for maintaining mouse embryonic stem cells (ESCs) that are primed for differentiation, whereas the function of CS has not yet been elucidated. To clarify the role of CS, we generated glucuronyltransferase-I-knockout ESCs lacking CS. We found that CS was required to maintain the pluripotency of ESCs and promoted initial ESC commitment to differentiation compared with HS. In addition, CS-A and CS-E polysaccharides, but not CS-C polysaccharides, bound to E-cadherin and enhanced ESC differentiation. Multiple-lineage differentiation was inhibited in chondroitinase ABC-digested wild-type ESCs. Collectively, these results suggest that CS is a novel determinant in controlling the functional integrity of ESCs via binding to E-cadherin.

  18. Vitamin B12 Metabolism during Pregnancy and in Embryonic Mouse Models

    Directory of Open Access Journals (Sweden)

    Maira A. Moreno-Garcia

    2013-09-01

    Full Text Available Vitamin B12 (cobalamin, Cbl is required for cellular metabolism. It is an essential coenzyme in mammals for two reactions: the conversion of homocysteine to methionine by the enzyme methionine synthase and the conversion of methylmalonyl-CoA to succinyl-CoA by the enzyme methylmalonyl-CoA mutase. Symptoms of Cbl deficiency are hematological, neurological and cognitive, including megaloblastic anaemia, tingling and numbness of the extremities, gait abnormalities, visual disturbances, memory loss and dementia. During pregnancy Cbl is essential, presumably because of its role in DNA synthesis and methionine synthesis; however, there are conflicting studies regarding an association between early pregnancy loss and Cbl deficiency. We here review the literature about the requirement for Cbl during pregnancy, and summarized what is known of the expression pattern and function of genes required for Cbl metabolism in embryonic mouse models.

  19. Dual Function of Wnt Signaling during Neuronal Differentiation of Mouse Embryonic Stem Cells

    Directory of Open Access Journals (Sweden)

    Hanjun Kim

    2015-01-01

    Full Text Available Activation of Wnt signaling enhances self-renewal of mouse embryonic and neural stem/progenitor cells. In contrast, undifferentiated ES cells show a very low level of endogenous Wnt signaling, and ectopic activation of Wnt signaling has been shown to block neuronal differentiation. Therefore, it remains unclear whether or not endogenous Wnt/β-catenin signaling is necessary for self-renewal or neuronal differentiation of ES cells. To investigate this, we examined the expression profiles of Wnt signaling components. Expression levels of Wnts known to induce β-catenin were very low in undifferentiated ES cells. Stable ES cell lines which can monitor endogenous activity of Wnt/β-catenin signaling suggest that Wnt signaling was very low in undifferentiated ES cells, whereas it increased during embryonic body formation or neuronal differentiation. Interestingly, application of small molecules which can positively (BIO, GSK3β inhibitor or negatively (IWR-1-endo, Axin stabilizer control Wnt/β-catenin signaling suggests that activation of that signaling at different time periods had differential effects on neuronal differentiation of 46C ES cells. Further, ChIP analysis suggested that β-catenin/TCF1 complex directly regulated the expression of Sox1 during neuronal differentiation. Overall, our data suggest that Wnt/β-catenin signaling plays differential roles at different time points of neuronal differentiation.

  20. Development of pacemaker properties and rhythmogenic mechanisms in the mouse embryonic respiratory network

    Science.gov (United States)

    Chevalier, Marc; Toporikova, Natalia; Simmers, John; Thoby-Brisson, Muriel

    2016-01-01

    Breathing is a vital rhythmic behavior generated by hindbrain neuronal circuitry, including the preBötzinger complex network (preBötC) that controls inspiration. The emergence of preBötC network activity during prenatal development has been described, but little is known regarding inspiratory neurons expressing pacemaker properties at embryonic stages. Here, we combined calcium imaging and electrophysiological recordings in mouse embryo brainstem slices together with computational modeling to reveal the existence of heterogeneous pacemaker oscillatory properties relying on distinct combinations of burst-generating INaP and ICAN conductances. The respective proportion of the different inspiratory pacemaker subtypes changes during prenatal development. Concomitantly, network rhythmogenesis switches from a purely INaP/ICAN-dependent mechanism at E16.5 to a combined pacemaker/network-driven process at E18.5. Our results provide the first description of pacemaker bursting properties in embryonic preBötC neurons and indicate that network rhythmogenesis undergoes important changes during prenatal development through alterations in both circuit properties and the biophysical characteristics of pacemaker neurons. DOI: http://dx.doi.org/10.7554/eLife.16125.001 PMID:27434668

  1. Differential radiosensitivity of mouse embryonic neurons and glia in cell culture

    International Nuclear Information System (INIS)

    Dambergs, R.; Kidson, C.

    1977-01-01

    The responses of neurons and glial cells to ultraviolet and γ-radiation were studied in cell cultures of embryonic mouse brains. A decrease in the ratio of glia to neurons occurred after both forms of irradiation. [ 3 H]thymidine labelling followed by autoradiography revealed that all glia were capable of replication, whereas 70 percent of neurons were non-replicating under the conditions of the study. Ultraviolet radiation caused a decrease in the proportion of replicating neurons but did not affect the proportion of replicating glia, whereas γ-radiation caused a decrease in DNA replication in both cell types. Levels of ultraviolet radiation-induced unscheduled DNA synthesis were lower in neurons than in glia. It is concluded that sensitivity to both ionizing and ultraviolet radiation of neurons and glial cells in embryonic brain cultures is determined primarily by the capacity for and state of DNA replication. Neurons which have already reached the stage of terminal differentiation are more resistant than replicating neurons of glial cells

  2. Generation of eggs from mouse embryonic stem cells and induced pluripotent stem cells.

    Science.gov (United States)

    Hayashi, Katsuhiko; Saitou, Mitinori

    2013-08-01

    Oogenesis is an integrated process through which an egg acquires the potential for totipotency, a fundamental condition for creating new individuals. Reconstitution of oogenesis in a culture that generates eggs with proper function from pluripotent stem cells (PSCs) is therefore one of the key goals in basic biology as well as in reproductive medicine. Here we describe a stepwise protocol for the generation of eggs from mouse PSCs, such as embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs). ESCs and iPSCs are first induced into primordial germ cell-like cells (PGCLCs) that are in turn aggregated with somatic cells of female embryonic gonads, the precursors for adult ovaries. Induction of PGCLCs followed by aggregation with the somatic cells takes up to 8 d. The aggregations are then transplanted under the ovarian bursa, in which PGCLCs grow into germinal vesicle (GV) oocytes in ∼1 month. The PGCLC-derived GV oocytes can be matured into eggs in 1 d by in vitro maturation (IVM), and they can be fertilized with spermatozoa by in vitro fertilization (IVF) to obtain healthy and fertile offspring. This method provides an initial step toward reconstitution of the entire process of oogenesis in vitro.

  3. Mechanical control of notochord morphogenesis by extra-embryonic tissues in mouse embryos.

    Science.gov (United States)

    Imuta, Yu; Koyama, Hiroshi; Shi, Dongbo; Eiraku, Mototsugu; Fujimori, Toshihiko; Sasaki, Hiroshi

    2014-05-01

    Mammalian embryos develop in coordination with extraembryonic tissues, which support embryonic development by implanting embryos into the uterus, supplying nutrition, providing a confined niche, and also providing patterning signals to embryos. Here, we show that in mouse embryos, the expansion of the amniotic cavity (AC), which is formed between embryonic and extraembryonic tissues, provides the mechanical forces required for a type of morphogenetic movement of the notochord known as convergent extension (CE) in which the cells converge to the midline and the tissue elongates along the antero-posterior (AP) axis. The notochord is stretched along the AP axis, and the expansion of the AC is required for CE. Both mathematical modeling and physical simulation showed that a rectangular morphology of the early notochord caused the application of anisotropic force along the AP axis to the notochord through the isotropic expansion of the AC. AC expansion acts upstream of planar cell polarity (PCP) signaling, which regulates CE movement. Our results highlight the importance of extraembryonic tissues as a source of the forces that control the morphogenesis of embryos. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  4. Embryoid bodies formation and differentiation from mouse embryonic stem cells in collagen/Matrigel scaffolds.

    Science.gov (United States)

    Zhou, Jin; Zhang, Ye; Lin, Qiuxia; Liu, Zhiqiang; Wang, Haibin; Duan, Cuimi; Wang, Yanmeng; Hao, Tong; Wu, Kuiwu; Wang, Changyong

    2010-07-01

    Embryonic stem (ES) cells have the potential to develop into any type of tissue and are considered as a promising source of seeding cells for tissue engineering and transplantation therapy. The main catalyst for ES cells differentiation is the growth into embryoid bodies (EBs), which are utilized widely as the trigger of in vitro differentiation. In this study, a novel method for generating EBs from mouse ES cells through culture in collagen/Matrigel scaffolds was successfully established. When single ES cells were seeded in three dimensional collagen/Matrigel scaffolds, they grew into aggregates gradually and formed simple EBs with circular structures. After 7 days' culture, they formed into cystic EBs that would eventually differentiate into the three embryonic germ layers. Evaluation of the EBs in terms of morphology and potential to differentiate indicated that they were typical in structure and could generate various cell types; they were also able to form into tissue-like structures. Moreover, with introduction of ascorbic acid, ES cells differentiated into cardiomyocytes efficiently and started contracting synchronously at day 19. The results demonstrated that collagen/Matrigel scaffolds supported EBs formation and their subsequent differentiation in a single three dimensional environment. Copyright 2010 Institute of Genetics and Developmental Biology and the Genetics Society of China. Published by Elsevier Ltd. All rights reserved.

  5. DNA context represents transcription regulation of the gene in mouse embryonic stem cells

    Science.gov (United States)

    Ha, Misook; Hong, Soondo

    2016-04-01

    Understanding gene regulatory information in DNA remains a significant challenge in biomedical research. This study presents a computational approach to infer gene regulatory programs from primary DNA sequences. Using DNA around transcription start sites as attributes, our model predicts gene regulation in the gene. We find that H3K27ac around TSS is an informative descriptor of the transcription program in mouse embryonic stem cells. We build a computational model inferring the cell-type-specific H3K27ac signatures in the DNA around TSS. A comparison of embryonic stem cell and liver cell-specific H3K27ac signatures in DNA shows that the H3K27ac signatures in DNA around TSS efficiently distinguish the cell-type specific H3K27ac peaks and the gene regulation. The arrangement of the H3K27ac signatures inferred from the DNA represents the transcription regulation of the gene in mESC. We show that the DNA around transcription start sites is associated with the gene regulatory program by specific interaction with H3K27ac.

  6. A reliable and economical method for gaining mouse embryonic fibroblasts capable of preparing feeder layers.

    Science.gov (United States)

    Jiang, Guangming; Wan, Xiaoju; Wang, Ming; Zhou, Jianhua; Pan, Jian; Wang, Baolong

    2016-08-01

    Mouse embryonic fibroblasts (MEFs) are widely used to prepare feeder layers for culturing embryonic stem cells (ESCs) or induced pluripotent stem cells (iPSCs) in vitro. Transportation lesions and exorbitant prices make the commercially obtained MEFs unsuitable for long term research. The aim of present study is to establish a method, which enables researchers to gain MEFs from mice and establish feeder layers by themselves in ordinary laboratories. MEFs were isolated from ICR mouse embryos at 12.5-17.5 day post-coitum (DPC) and cultured in vitro. At P2-P7, the cells were inactivated with mitomycin C or by X-ray irradiation. Then they were used to prepare feeder layers. The key factors of the whole protocol were analyzed to determine the optimal conditions for the method. The results revealed MEFs isolated at 12.5-13.5 DPC, and cultured to P3 were the best choice for feeder preparation, those P2 and P4-P5 MEFs were also suitable for the purpose. The P3-P5 MEFs treated with 10 μg/ml of mitomycin C for 3 h, or irradiated with X-ray at 1.5 Gy/min for 25 Gy were the most suitable feeder cells. Treating MEFs with 10 μg/ml of mitomycin C for 2.5 h, 15 μg/ml for 2.0 h, or irradiating the cells with 20 Gy of X-ray at 2.0 Gy/min could all serve as alternative methods for P3-P4 cells. Our study provides a reliable and economical way to obtain large amount of qualified MEFs for long term research of ESCs or iPSCs.

  7. Structural organization and chromosomal assignment of the mouse embryonic TEA domain-containing factor (ETF) gene.

    Science.gov (United States)

    Suzuki, K; Yasunami, M; Matsuda, Y; Maeda, T; Kobayashi, H; Terasaki, H; Ohkubo, H

    1996-09-01

    Embryonic TEA domain-containing factor (ETF) belongs to the family of proteins structurally related to transcriptional enhancer factor-1 (TEF-1) and is implicated in neural development. Isolation and characterization of the cosmid clones encoding the mouse ETF gene (Etdf) revealed that Etdf spans approximately 17.9 kb and consists of 12 exons. The exon-intron structure of Etdf closely resembles that of the Drosophila scalloped gene, indicating that these genes may have evolved from a common ancestor. The multiple transcription initiation sites revealed by S1 protection and primer extension analyses are consistent with the absence of the canonical TATA and CAAT boxes in the 5'-flanking region, which contains many potential regulatory sequences, such as the E-box, N-box, Sp1 element, GATA-1 element, TAATGARAT element, and B2 short interspersed element (SINE) as well as several direct and inverted repeat sequences. The Etdf locus was assigned to the proximal region of mouse chromosome 7 using fluorescence in situ hybridization and linkage mapping analyses. These results provide the molecular basis for studying the regulation, in vivo function, and evolution of Etdf.

  8. Loss of ATF2 function leads to cranial motoneuron degeneration during embryonic mouse development.

    Directory of Open Access Journals (Sweden)

    Julien Ackermann

    2011-04-01

    Full Text Available The AP-1 family transcription factor ATF2 is essential for development and tissue maintenance in mammals. In particular, ATF2 is highly expressed and activated in the brain and previous studies using mouse knockouts have confirmed its requirement in the cerebellum as well as in vestibular sense organs. Here we present the analysis of the requirement for ATF2 in CNS development in mouse embryos, specifically in the brainstem. We discovered that neuron-specific inactivation of ATF2 leads to significant loss of motoneurons of the hypoglossal, abducens and facial nuclei. While the generation of ATF2 mutant motoneurons appears normal during early development, they undergo caspase-dependent and independent cell death during later embryonic and foetal stages. The loss of these motoneurons correlates with increased levels of stress activated MAP kinases, JNK and p38, as well as aberrant accumulation of phosphorylated neurofilament proteins, NF-H and NF-M, known substrates for these kinases. This, together with other neuropathological phenotypes, including aberrant vacuolisation and lipid accumulation, indicates that deficiency in ATF2 leads to neurodegeneration of subsets of somatic and visceral motoneurons of the brainstem. It also confirms that ATF2 has a critical role in limiting the activities of stress kinases JNK and p38 which are potent inducers of cell death in the CNS.

  9. Golga5 is dispensable for mouse embryonic development and postnatal survival.

    Science.gov (United States)

    McGee, Lynessa J; Jiang, Alex L; Lan, Yu

    2017-07-01

    Golgins are a family of coiled-coil proteins located at the cytoplasmic surface of the Golgi apparatus and have been implicated in maintaining Golgi structural integrity through acting as tethering factors for retrograde vesicle transport. Whereas knockdown of several individual golgins in cultured cells caused Golgi fragmentation and disruption of vesicle trafficking, analysis of mutant mouse models lacking individual golgins have discovered tissue-specific developmental functions. Recently, homozygous loss of function of GOLGA2, of which previous in vitro studies suggested an essential role in maintenance of Golgi structure and in mitosis, has been associated with a neuromuscular disorder in human patients, which highlights the need for understanding the developmental roles of the golgins in vivo. We report here generation of Golga5-deficient mice using CRISPR/Cas9-mediated genome editing. Although knockdown studies in cultured cells have implicated Golga5 in maintenance of Golgi organization, we show that Golga5 is not required for mouse embryonic development, postnatal survival, or fertility. Moreover, whereas Golga5 is structurally closely related to Golgb1, we show that inactivation of Golga5 does not enhance the severity of developmental defects in Golgb1-deficient mice. The Golga5-deficient mice enable further investigation of the roles and functional specificity of golgins in development and diseases. © 2017 Wiley Periodicals, Inc.

  10. In vitro differentiation and maturation of mouse embryonic stem cells into hepatocytes

    International Nuclear Information System (INIS)

    Ishii, Takamichi; Yasuchika, Kentaro; Fujii, Hideaki; Hoppo, Toshitaka; Baba, Shinji; Naito, Masato; Machimoto, Takafumi; Kamo, Naoko; Suemori, Hirofumi; Nakatsuji, Norio; Ikai, Iwao

    2005-01-01

    It is difficult to induce the maturation of embryonic stem (ES) cells into hepatocytes in vitro. We previously reported that Thy1-positive mesenchymal cells derived from the mouse fetal liver promote the maturation of hepatic progenitor cells. Here, we isolated alpha-fetoprotein (AFP)-producing cells from mouse ES cells for subsequent differentiation into hepatocytes in vitro by coculture with Thy1-positive cells. ES cells expressing green fluorescent protein (GFP) under the control of an AFP promoter were cultured under serum- and feeder layer-free culture conditions. The proportion of GFP-positive cells plateaued at 41.6 ± 12.2% (means ± SD) by day 7. GFP-positive cells, isolated by flow cytometry, were cultured in the presence or absence of Thy1-positive cells as a feeder layer. Isolated GFP-positive cells were stained for AFP, Foxa2, and albumin. The expression of mRNAs encoding tyrosine amino transferase, tryptophan 2,3-dioxygenase, and glucose-6-phosphatase were only detected following coculture with Thy1-positive cells. Following coculture with Thy1-positive cells, the isolated cells produced and stored glycogen. Ammonia clearance activity was also enhanced following coculture. Electron microscopic analysis indicated that the cocultured cells exhibited the morphologic features of mature hepatocytes. In conclusion, coculture with Thy1-positive cells in vitro induced the maturation of AFP-producing cells isolated from ES cell cultures into hepatocytes

  11. Resveratrol protects mouse embryonic stem cells from ionizing radiation by accelerating recovery from DNA strand breakage.

    Science.gov (United States)

    Denissova, Natalia G; Nasello, Cara M; Yeung, Percy L; Tischfield, Jay A; Brenneman, Mark A

    2012-01-01

    Resveratrol has elicited many provocative anticancer effects in laboratory animals and cultured cells, including reduced levels of oxidative DNA damage, inhibition of tumor initiation and progression and induction of apoptosis in tumor cells. Use of resveratrol as a cancer-preventive agent in humans will require that its anticancer effects not be accompanied by damage to normal tissue stem or progenitor cells. In mouse embryonic stem cells (mESC) or early mouse embryos exposed to ethanol, resveratrol has been shown to suppress apoptosis and promote survival. However, in cells exposed to genotoxic stress, survival may come at the expense of genome stability. To learn whether resveratrol can protect stem cells from DNA damage and to study its effects on genomic integrity, we exposed mESC pretreated with resveratrol to ionizing radiation (IR). Forty-eight hours pretreatment with a comparatively low concentration of resveratrol (10 μM) improved survival of mESC >2-fold after exposure to 5 Gy of X-rays. Cells pretreated with resveratrol sustained the same levels of reactive oxygen species and DNA strand breakage after IR as mock-treated controls, but repaired DNA damage more rapidly and resumed cell division sooner. Frequencies of IR-induced mutation at a chromosomal reporter locus were not increased in cells pretreated with resveratrol as compared with controls, indicating that resveratrol can improve viability in mESC after DNA damage without compromising genomic integrity.

  12. Inhibition of chondroitin sulfate glycosaminoglycans incorporation affected odontoblast differentiation in cultured embryonic mouse molars.

    Science.gov (United States)

    Liu, Lipei; Chen, Weiting; Li, Lefeng; Xu, Fangfang; Jiang, Beizhan

    2017-12-01

    Chondroitin sulfate proteoglycan (CSPG) is an important component of extracellular matrix (ECM), it is composed of a core protein and one or more chondroitin sulfate glycosaminoglycan side chains (CS-GAGs). To investigate the roles of its CS-GAGs in dentinogenesis, the mouse mandibular first molar tooth germs at early bell stage were cultivated with or without β-xyloside. As expected, the CS-GAGs were inhibited on their incorporation to CSPGs by β-xyloside, accompanied by the change of morphology of the cultured tooth germs. The histological results and the transmission electron microscopy (TEM) investigation indicated that β-xyloside exhibited obvious inhibiting effects on odontoblasts differentiation compared with the control group. Meanwhile the results of immunohistochemistry, in situ hybridization and quantitative RT-PCR for type I collagen, dentin matrix acidic phosphoprotein 1 and dentin sialophosphoprotein, the products of differentiated odontoblasts, further proved that odontoblasts differentiation was inhibited. Collagen fibers detected in TEM decreased and arranged in disorder as well. Thus we conclude that the inhibition of CS-GAGs incorporation to CSPGs can affect odontoblast differentiation in cultured embryonic mouse molars.

  13. ZO-1 and ZO-2 are required for extra-embryonic endoderm integrity, primitive ectoderm survival and normal cavitation in embryoid bodies derived from mouse embryonic stem cells.

    Directory of Open Access Journals (Sweden)

    Dominic C Y Phua

    Full Text Available The Zonula Occludens proteins ZO-1 and ZO-2 are cell-cell junction-associated adaptor proteins that are essential for the structural and regulatory functions of tight junctions in epithelial cells and their absence leads to early embryonic lethality in mouse models. Here, we use the embryoid body, an in vitro peri-implantation mouse embryogenesis model, to elucidate and dissect the roles ZO-1 and ZO-2 play in epithelial morphogenesis and de novo tight junction assembly. Through the generation of individual or combined ZO-1 and ZO-2 null embryoid bodies, we show that their dual deletion prevents tight junction formation, resulting in the disorganization and compromised barrier function of embryoid body epithelial layers. The disorganization is associated with poor microvilli development, fragmented basement membrane deposition and impaired cavity formation, all of which are key epithelial tissue morphogenetic processes. Expression of Podocalyxin, which positively regulates the formation of microvilli and the apical membrane, is repressed in embryoid bodies lacking both ZO-1 and ZO-2 and this correlates with an aberrant submembranous localization of Ezrin. The null embryoid bodies thus give an insight into how the two ZO proteins influence early mouse embryogenesis and possible mechanisms underlying the embryonic lethal phenotype.

  14. Rigid microenvironments promote cardiac differentiation of mouse and human embryonic stem cells

    Science.gov (United States)

    Arshi, Armin; Nakashima, Yasuhiro; Nakano, Haruko; Eaimkhong, Sarayoot; Evseenko, Denis; Reed, Jason; Stieg, Adam Z.; Gimzewski, James K.; Nakano, Atsushi

    2013-04-01

    While adult heart muscle is the least regenerative of tissues, embryonic cardiomyocytes are proliferative, with embryonic stem (ES) cells providing an endless reservoir. In addition to secreted factors and cell-cell interactions, the extracellular microenvironment has been shown to play an important role in stem cell lineage specification, and understanding how scaffold elasticity influences cardiac differentiation is crucial to cardiac tissue engineering. Though previous studies have analyzed the role of matrix elasticity on the function of differentiated cardiomyocytes, whether it affects the induction of cardiomyocytes from pluripotent stem cells is poorly understood. Here, we examine the role of matrix rigidity on cardiac differentiation using mouse and human ES cells. Culture on polydimethylsiloxane (PDMS) substrates of varied monomer-to-crosslinker ratios revealed that rigid extracellular matrices promote a higher yield of de novo cardiomyocytes from undifferentiated ES cells. Using a genetically modified ES system that allows us to purify differentiated cardiomyocytes by drug selection, we demonstrate that rigid environments induce higher cardiac troponin T expression, beating rate of foci, and expression ratio of adult α- to fetal β- myosin heavy chain in a purified cardiac population. M-mode and mechanical interferometry image analyses demonstrate that these ES-derived cardiomyocytes display functional maturity and synchronization of beating when co-cultured with neonatal cardiomyocytes harvested from a developing embryo. Together, these data identify matrix stiffness as an independent factor that instructs not only the maturation of already differentiated cardiomyocytes but also the induction and proliferation of cardiomyocytes from undifferentiated progenitors. Manipulation of the stiffness will help direct the production of functional cardiomyocytes en masse from stem cells for regenerative medicine purposes.

  15. Cerium oxide nanoparticles stimulate proliferation of primary mouse embryonic fibroblasts in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Popov, Anton L., E-mail: antonpopovleonid@gmail.com [Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Pushchino, Moscow region (Russian Federation); Popova, Nelly R. [Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Pushchino, Moscow region (Russian Federation); Selezneva, Irina I. [Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Pushchino, Moscow region (Russian Federation); Pushchino State Institute of Natural sciences, Pushchino, Moscow region (Russian Federation); Akkizov, Azamat Y. [Kabardino-Balkarian State University, Nalchik (Russian Federation); Ivanov, Vladimir K. [Kurnakov Institute of General and Inorganic Chemistry, Russian Academy of Sciences, Moscow (Russian Federation); National Research Tomsk State University, Tomsk (Russian Federation)

    2016-11-01

    The increasing application of cell therapy technologies in the treatment of various diseases requires the development of new effective methods for culturing primary cells. The major limitation for the efficient use of autologous cell material is the low rate of cell proliferation. Successful cell therapy requires sufficient amounts of cell material over a short period of time with the preservation of their differentiation and proliferative potential. In this regard, the development of novel, highly efficient stimulators of proliferative activity in stem cells is a truly urgent task. In this paper we have demonstrated that citrate-stabilized cerium oxide nanoparticles (nanoceria) enhance the proliferative activity of primary mouse embryonic fibroblasts in vitro. Cerium oxide nanoparticles stimulate cell proliferation in a wide range of concentrations (10{sup −3} M–10{sup −9} M) through reduction of intracellular levels of reactive oxygen species (ROS) during the lag phase of cell growth and by modulating the expression level of the major antioxidant enzymes. We found the optimal concentration of nanoceria, which provides the greatest acceleration of cell proliferation in vitro, while maintaining the levels of intracellular ROS and mRNA of antioxidant enzymes in the physiological range. Our results confirm that nanocrystalline ceria can be considered as a basis for effective and inexpensive supplements in cell culturing. - Highlights: • Citrate-stabilized cerium oxide nanoparticles are shown to stimulate proliferation of primary embryonic cells in vitro. • Some of mechanisms involved in stimulating of the proliferation by CeO{sub 2} have been uncovered. • The most effective (optimal) concentration of CeO{sub 2} nanoparticles for stimulation of proliferation was determined.

  16. Interactions between the otitis media gene, Fbxo11, and p53 in the mouse embryonic lung.

    Science.gov (United States)

    Tateossian, Hilda; Morse, Susan; Simon, Michelle M; Dean, Charlotte H; Brown, Steve D M

    2015-12-01

    Otitis media with effusion (OME) is the most common cause of hearing loss in children, and tympanostomy (ear tube insertion) to alleviate the condition remains the commonest surgical intervention in children in the developed world. Chronic and recurrent forms of otitis media (OM) are known to have a very substantial genetic component; however, until recently, little was known of the underlying genes involved. The Jeff mouse mutant carries a mutation in the Fbxo11 gene, a member of the F-box family, and develops deafness due to a chronic proliferative OM. We previously reported that Fbxo11 is involved in the regulation of transforming growth factor beta (TGF-β) signalling by regulating the levels of phospho-Smad2 in the epithelial cells of palatal shelves, eyelids and airways of the lungs. It has been proposed that FBXO11 regulates the cell's response to TGF-β through the ubiquitination of CDT2. Additional substrates for FBXO11 have been identified, including p53. Here, we have studied both the genetic and biochemical interactions between FBXO11 and p53 in order to better understand the function of FBXO11 in epithelial development and its potential role in OM. In mice, we show that p53 (also known as Tp53) homozygous mutants and double heterozygous mutants (Jf/+ p53/+) exhibit similar epithelial developmental defects to Fbxo11 homozygotes. FBXO11 and p53 interact in the embryonic lung, and mutation in Fbxo11 prevents the interaction with p53. Both p53 and double mutants show raised levels of pSMAD2, recapitulating that seen in Fbxo11 homozygotes. Overall, our results support the conclusion that FBXO11 regulates the TGF-β pathway in the embryonic lung via cross-talk with p53. © 2015. Published by The Company of Biologists Ltd.

  17. Overexpression of histone demethylase Fbxl10 leads to enhanced migration in mouse embryonic fibroblasts

    Energy Technology Data Exchange (ETDEWEB)

    Rohde, Magdalena; Sievers, Elisabeth; Janzer, Andreas [Institute of Pathology, University of Bonn, Sigmund-Freud-Strasse 25, 53127 Bonn (Germany); Willmann, Dominica [Urologische Klinik/Frauenklinik und Zentrale Klinische Forschung, Klinikum der Universität Freiburg, Breisacherstrasse 66, 79106 Freiburg (Germany); Egert, Angela; Schorle, Hubert [Department of Developmental Pathology, Institute of Pathology, University of Bonn, Sigmund-Freud-Strasse 25, 53127 Bonn (Germany); Schüle, Roland [Urologische Klinik/Frauenklinik und Zentrale Klinische Forschung, Klinikum der Universität Freiburg, Breisacherstrasse 66, 79106 Freiburg (Germany); Kirfel, Jutta, E-mail: Jutta.Kirfel@ukb.uni-bonn.de [Institute of Pathology, University of Bonn, Sigmund-Freud-Strasse 25, 53127 Bonn (Germany)

    2016-11-01

    Cell migration is a central process in the development and maintenance of multicellular organisms. Tissue formation during embryonic development, wound healing, immune responses and invasive tumors all require the orchestrated movement of cells to specific locations. Histone demethylase proteins alter transcription by regulating the chromatin state at specific gene loci. FBXL10 is a conserved and ubiquitously expressed member of the JmjC domain-containing histone demethylase family and is implicated in the demethylation of H3K4me3 and H3K36me2 and thereby removing active chromatin marks. However, the physiological role of FBXL10 in vivo remains largely unknown. Therefore, we established an inducible gain of function model to analyze the role of Fbxl10 and compared wild-type with Fbxl10 overexpressing mouse embryonic fibroblasts (MEFs). Our study shows that overexpression of Fbxl10 in MEFs doesn’t influence the proliferation capability but leads to an enhanced migration capacity in comparison to wild-type MEFs. Transcriptome and ChIP-seq experiments demonstrated that Fbxl10 binds to genes involved in migration like Areg, Mdk, Lmnb1, Thbs1, Mgp and Cxcl12. Taken together, our results strongly suggest that Fbxl10 plays a critical role in migration by binding to the promoter region of migration-associated genes and thereby might influences cell behaviour to a possibly more aggressive phenotype. - Highlights: • Migration capability of MEFs is enhanced after Fbxl10 upregulation. • Overexpression of Fbxl10 induced migration-associated genes. • Fbxl10 binds directly to migration-associated genes.

  18. NDR Kinases Are Essential for Somitogenesis and Cardiac Looping during Mouse Embryonic Development.

    Directory of Open Access Journals (Sweden)

    Debora Schmitz-Rohmer

    Full Text Available Studies of mammalian tissue culture cells indicate that the conserved and distinct NDR isoforms, NDR1 and NDR2, play essential cell biological roles. However, mice lacking either Ndr1 or Ndr2 alone develop normally. Here, we studied the physiological consequences of inactivating both NDR1 and NDR2 in mice, showing that the lack of both Ndr1/Ndr2 (called Ndr1/2-double null mutants causes embryonic lethality. In support of compensatory roles for NDR1 and NDR2, total protein and activating phosphorylation levels of the remaining NDR isoform were elevated in mice lacking either Ndr1 or Ndr2. Mice retaining one single wild-type Ndr allele were viable and fertile. Ndr1/2-double null embryos displayed multiple phenotypes causing a developmental delay from embryonic day E8.5 onwards. While NDR kinases are not required for notochord formation, the somites of Ndr1/2-double null embryos were smaller, irregularly shaped and unevenly spaced along the anterior-posterior axis. Genes implicated in somitogenesis were down-regulated and the normally symmetric expression of Lunatic fringe, a component of the Notch pathway, showed a left-right bias in the last forming somite in 50% of all Ndr1/2-double null embryos. In addition, Ndr1/2-double null embryos developed a heart defect that manifests itself as pericardial edemas, obstructed heart tubes and arrest of cardiac looping. The resulting cardiac insufficiency is the likely cause of the lethality of Ndr1/2-double null embryos around E10. Taken together, we show that NDR kinases compensate for each other in vivo in mouse embryos, explaining why mice deficient for either Ndr1 or Ndr2 are viable. Ndr1/2-double null embryos show defects in somitogenesis and cardiac looping, which reveals their essential functions and shows that the NDR kinases are critically required during the early phase of organogenesis.

  19. Overexpression of histone demethylase Fbxl10 leads to enhanced migration in mouse embryonic fibroblasts

    International Nuclear Information System (INIS)

    Rohde, Magdalena; Sievers, Elisabeth; Janzer, Andreas; Willmann, Dominica; Egert, Angela; Schorle, Hubert; Schüle, Roland; Kirfel, Jutta

    2016-01-01

    Cell migration is a central process in the development and maintenance of multicellular organisms. Tissue formation during embryonic development, wound healing, immune responses and invasive tumors all require the orchestrated movement of cells to specific locations. Histone demethylase proteins alter transcription by regulating the chromatin state at specific gene loci. FBXL10 is a conserved and ubiquitously expressed member of the JmjC domain-containing histone demethylase family and is implicated in the demethylation of H3K4me3 and H3K36me2 and thereby removing active chromatin marks. However, the physiological role of FBXL10 in vivo remains largely unknown. Therefore, we established an inducible gain of function model to analyze the role of Fbxl10 and compared wild-type with Fbxl10 overexpressing mouse embryonic fibroblasts (MEFs). Our study shows that overexpression of Fbxl10 in MEFs doesn’t influence the proliferation capability but leads to an enhanced migration capacity in comparison to wild-type MEFs. Transcriptome and ChIP-seq experiments demonstrated that Fbxl10 binds to genes involved in migration like Areg, Mdk, Lmnb1, Thbs1, Mgp and Cxcl12. Taken together, our results strongly suggest that Fbxl10 plays a critical role in migration by binding to the promoter region of migration-associated genes and thereby might influences cell behaviour to a possibly more aggressive phenotype. - Highlights: • Migration capability of MEFs is enhanced after Fbxl10 upregulation. • Overexpression of Fbxl10 induced migration-associated genes. • Fbxl10 binds directly to migration-associated genes.

  20. Protective effects of resveratrol on ethanol-induced apoptosis in embryonic stem cells and disruption of embryonic development in mouse blastocysts

    International Nuclear Information System (INIS)

    Huang, L.-H.; Shiao, N.-H.; Hsuuw, Y.-D.; Chan, W.-H.

    2007-01-01

    Previous studies have established that ethanol induces apoptosis, but the precise molecular mechanisms are currently unclear. Here, we show that 0.3-1.0% (w/v) ethanol induces apoptosis in mouse blastocysts and that resveratrol, a grape-derived phytoalexin with known antioxidant and anti-inflammatory properties, prevents ethanol-induced apoptosis and inhibition of cell proliferation. Moreover, ethanol-treated blastocysts show normal levels of implantation on culture dishes in vitro but a reduced ability to reach the later stages of embryonic development. Pretreatment with resveratrol prevented ethanol-induced disruption of embryonic development in vitro and in vivo. In an in vitro cell-based assay, we further found that ethanol increases the production of reactive oxygen species in ESC-B5 embryonic stem cells, leading to an increase in the intracellular concentrations of cytoplasmic free Ca 2+ and NO, loss of mitochondrial membrane potential, mitochondrial release of cytochrome c, activation of caspase-9 and -3, and apoptosis. These changes were blocked by pretreatment with resveratrol. Based on these results, we propose a model for the protective effect of resveratrol on ethanol-induced cell injury in blastocysts and ESC-B5 cells

  1. Selection-independent generation of gene knockout mouse embryonic stem cells using zinc-finger nucleases.

    Directory of Open Access Journals (Sweden)

    Anna Osiak

    Full Text Available Gene knockout in murine embryonic stem cells (ESCs has been an invaluable tool to study gene function in vitro or to generate animal models with altered phenotypes. Gene targeting using standard techniques, however, is rather inefficient and typically does not exceed frequencies of 10(-6. In consequence, the usage of complex positive/negative selection strategies to isolate targeted clones has been necessary. Here, we present a rapid single-step approach to generate a gene knockout in mouse ESCs using engineered zinc-finger nucleases (ZFNs. Upon transient expression of ZFNs, the target gene is cleaved by the designer nucleases and then repaired by non-homologous end-joining, an error-prone DNA repair process that introduces insertions/deletions at the break site and therefore leads to functional null mutations. To explore and quantify the potential of ZFNs to generate a gene knockout in pluripotent stem cells, we generated a mouse ESC line containing an X-chromosomally integrated EGFP marker gene. Applying optimized conditions, the EGFP locus was disrupted in up to 8% of ESCs after transfection of the ZFN expression vectors, thus obviating the need of selection markers to identify targeted cells, which may impede or complicate downstream applications. Both activity and ZFN-associated cytotoxicity was dependent on vector dose and the architecture of the nuclease domain. Importantly, teratoma formation assays of selected ESC clones confirmed that ZFN-treated ESCs maintained pluripotency. In conclusion, the described ZFN-based approach represents a fast strategy for generating gene knockouts in ESCs in a selection-independent fashion that should be easily transferrable to other pluripotent stem cells.

  2. EXAMINATION OF THE GERM CELL CHIMERA FORMING POTENTIAL OF MOUSE EMBRYONIC STEM CELLS

    Directory of Open Access Journals (Sweden)

    V.B. CÂRSTEA

    2007-05-01

    Full Text Available The aim of this study was to examine the factors, which influence the chimeraforming potential of mouse embryonic stem cells (ES cells. In our work, we examinethe chimera producing ability of R1 and R1/E mouse ES cell lines. We found that thepassage number affects chimera-forming capability of the ES cells. With theincreasing of the passage number, it could be getting less chimera animal, and onlythe R1/E ES cell line derived cells could contribute to the germ cells. At first, wecompared the marker of pluripotency using immunostaining and RT PCR, but wecould not find any difference between the R1 and R1/E cell in this way. Atchromosome analysis, we found, that the number of aneuploid cells, in R1 ES cellline, dramatically increased after 10 passages. We thought that the reason is thatduring the cell division Y chromosome could not arrange correctly between the twonewly derived progeny cells. To prove our conception, we made X and YchromosomeFISH analyses. We found, that the aneuploid R1 and R1/E ES cellscontain only one X and one Y chromosome, so not the loss of Y chromosome causethe problem at the germ cell formation. At last, we made the karyotypeanalysis of R1 and R1/E ES cells at different passages. The karyotype analysisdemonstrated that in the case of R1 ES cell line, the 41 and 42-chromosomecontaining cells hold trisomy. With the increasing of the passages number, thenumber of trisomy containing aneuploid cells increased. The aneuploid ES cells cancontribute to the different tissuses of chimera animals, but cannot form viable germcells.

  3. EXAMINATION OF THE GERM CELL CHIMERA FORMING POTENTIAL OF MOUSE EMBRYONIC STEM CELLS

    Directory of Open Access Journals (Sweden)

    CÂRSTEA V. B

    2007-01-01

    Full Text Available The aim of this study was to examine the factors, which influence the chimeraforming potential of mouse embryonic stem cells (ES cells. In our work, we examinethe chimera producing ability of R1 and R1/E mouse ES cell lines. We found that thepassage number affects chimera-forming capability of the ES cells. With theincreasing of the passage number, it could be getting less chimera animal, and onlythe R1/E ES cell line derived cells could contribute to the germ cells. At first, wecompared the marker of pluripotency using immunostaining and RT PCR, but wecould not find any difference between the R1 and R1/E cell in this way. Atchromosome analysis, we found, that the number of aneuploid cells, in R1 ES cellline, dramatically increased after 10 passages. We thought that the reason is thatduring the cell division Y chromosome could not arrange correctly between the twonewly derived progeny cells. To prove our conception, we made X and YchromosomeFISH analyses. We found, that the aneuploid R1 and R1/E ES cellscontain only one X and one Y chromosome, so not the loss of Y chromosome causethe problem at the germ cell formation. At last, we made the karyotypeanalysis of R1 and R1/E ES cells at different passages. The karyotype analysisdemonstrated that in the case of R1 ES cell line, the 41 and 42-chromosomecontaining cells hold trisomy. With the increasing of the passages number, thenumber of trisomy containing aneuploid cells increased. The aneuploid ES cells cancontribute to the different tissuses of chimera animals, but cannot form viable germcells.

  4. p75 neurotrophin receptor is involved in proliferation of undifferentiated mouse embryonic stem cells

    Energy Technology Data Exchange (ETDEWEB)

    Moscatelli, Ilana; Pierantozzi, Enrico; Camaioni, Antonella; Siracusa, Gregorio [Department of Public Health and Cell Biology, Section of Histology and Embryology, University of Rome Tor Vergata, Via Montpellier 1, 00133 Rome (Italy); Campagnolo, Luisa, E-mail: campagno@med.uniroma2.it [Department of Public Health and Cell Biology, Section of Histology and Embryology, University of Rome Tor Vergata, Via Montpellier 1, 00133 Rome (Italy)

    2009-11-01

    Neurotrophins and their receptors are known to play a role in the proliferation and survival of many different cell types of neuronal and non-neuronal lineages. In addition, there is much evidence in the literature showing that the p75 neurotrophin receptor (p75{sup NTR}), alone or in association with members of the family of Trk receptors, is expressed in a wide variety of stem cells, although its role in such cells has not been completely elucidated. In the present work we have investigated the expression of p75{sup NTR} and Trks in totipotent and pluripotent cells, the mouse pre-implantation embryo and embryonic stem and germ cells (ES and EG cells). p75{sup NTR} and TrkA can be first detected in the blastocyst from which ES cell lines are derived. Mouse ES cells retain p75{sup NTR}/TrkA expression. Nerve growth factor is the only neurotrophin able to stimulate ES cell growth in culture, without affecting the expression of stem cell markers, alkaline phosphatase, Oct4 and Nanog. Such proliferation effect was blocked by antagonizing either p75{sup NTR} or TrkA. Interestingly, immunoreactivity to anti-p75{sup NTR} antibodies is lost upon ES cell differentiation. The expression pattern of neurotrophin receptors in murine ES cells differs from human ES cells, that only express TrkB and C, and do not respond to NGF. In this paper we also show that, while primordial germ cells (PGC) do not express p75{sup NTR}, when they are made to revert to an ES-like phenotype, becoming EG cells, expression of p75{sup NTR} is turned on.

  5. p75 neurotrophin receptor is involved in proliferation of undifferentiated mouse embryonic stem cells

    International Nuclear Information System (INIS)

    Moscatelli, Ilana; Pierantozzi, Enrico; Camaioni, Antonella; Siracusa, Gregorio; Campagnolo, Luisa

    2009-01-01

    Neurotrophins and their receptors are known to play a role in the proliferation and survival of many different cell types of neuronal and non-neuronal lineages. In addition, there is much evidence in the literature showing that the p75 neurotrophin receptor (p75 NTR ), alone or in association with members of the family of Trk receptors, is expressed in a wide variety of stem cells, although its role in such cells has not been completely elucidated. In the present work we have investigated the expression of p75 NTR and Trks in totipotent and pluripotent cells, the mouse pre-implantation embryo and embryonic stem and germ cells (ES and EG cells). p75 NTR and TrkA can be first detected in the blastocyst from which ES cell lines are derived. Mouse ES cells retain p75 NTR /TrkA expression. Nerve growth factor is the only neurotrophin able to stimulate ES cell growth in culture, without affecting the expression of stem cell markers, alkaline phosphatase, Oct4 and Nanog. Such proliferation effect was blocked by antagonizing either p75 NTR or TrkA. Interestingly, immunoreactivity to anti-p75 NTR antibodies is lost upon ES cell differentiation. The expression pattern of neurotrophin receptors in murine ES cells differs from human ES cells, that only express TrkB and C, and do not respond to NGF. In this paper we also show that, while primordial germ cells (PGC) do not express p75 NTR , when they are made to revert to an ES-like phenotype, becoming EG cells, expression of p75 NTR is turned on.

  6. Implantable Self-Powered Low-Level Laser Cure System for Mouse Embryonic Osteoblasts' Proliferation and Differentiation.

    Science.gov (United States)

    Tang, Wei; Tian, Jingjing; Zheng, Qiang; Yan, Lin; Wang, Jiangxue; Li, Zhou; Wang, Zhong Lin

    2015-08-25

    Bone remodeling or orthodontic treatment is usually a long-term process. It is highly desirable to speed up the process for effective medical treatment. In this work, a self-powered low-level laser cure system for osteogenesis is developed using the power generated by the triboelectric nanogenerator. It is found that the system significantly accelerated the mouse embryonic osteoblasts' proliferation and differentiation, which is essential for bone and tooth healing. The system is further demonstrated to be driven by a living creature's motions, such as human walking or a mouse's breathing, suggesting its practical use as a portable or implantable clinical cure for bone remodeling or orthodontic treatment.

  7. Canonical Wnt signaling induces a primitive endoderm metastable state in mouse embryonic stem cells.

    Science.gov (United States)

    Price, Feodor D; Yin, Hang; Jones, Andrew; van Ijcken, Wilfred; Grosveld, Frank; Rudnicki, Michael A

    2013-04-01

    Activation of the canonical Wnt signaling pathway synergizes with leukemia inhibitory factor (LIF) to maintain pluripotency of mouse embryonic stem cells (mESCs). However, in the absence of LIF, Wnt signaling is unable to maintain ESCs in the undifferentiated state. To investigate the role of canonical Wnt signaling in pluripotency and lineage specification, we expressed Wnt3a in mESCs and characterized them in growth and differentiation. We found that activated canonical Wnt signaling induced the formation of a reversible metastable primitive endoderm state in mESC. Upon subsequent differentiation, Wnt3a-stimulated mESCs gave rise to large quantities of visceral endoderm. Furthermore, we determined that the ability of canonical Wnt signaling to induce a metastable primitive endoderm state was mediated by Tbx3. Our data demonstrates a specific role for canonical Wnt signaling in promoting pluripotency while at the same time priming cells for subsequent differentiation into the primitive endoderm lineage. Copyright © 2013 AlphaMed Press.

  8. Mesenchymal and embryonic characteristics of stem cells obtained from mouse dental pulp.

    Science.gov (United States)

    Guimarães, Elisalva Teixeira; Cruz, Gabriela Silva; de Jesus, Alan Araújo; Lacerda de Carvalho, Acácia Fernandes; Rogatto, Silvia Regina; Pereira, Lygia da Veiga; Ribeiro-dos-Santos, Ricardo; Soares, Milena Botelho Pereira

    2011-11-01

    Several studies have demonstrated that human dental pulp is a source of mesenchymal stem cells. To better understand the biological properties of these cells we isolated and characterized stem cells from the dental pulp of EGFP transgenic mice. The pulp tissue was gently separated from the roots of teeth extracted from C57BL/6 mice, and cultured under appropriate conditions. Flow cytometry, RT-PCR, light microscopy (staining for alkaline phosphatase) and immunofluorescence were used to investigate the expression of stem cell markers. The presence of chromosomal abnormalities was evaluated by G banding. The mouse dental pulp stem cells (mDPSC) were highly proliferative, plastic-adherent, and exhibited a polymorphic morphology predominantly with stellate or fusiform shapes. The presence of cell clusters was observed in cultures of mDPSC. Some cells were positive for alkaline phosphatase. The karyotype was normal until the 5th passage. The Pou5f1/Oct-4 and ZFP42/Rex-1, but not Nanog transcripts were detected in mDPSC. Flow cytometry and fluorescence analyses revealed the presence of a heterogeneous population positive for embryonic and mesenchymal cell markers. Adipogenic, chondrogenic and osteogenic differentiation was achieved after two weeks of cell culture under chemically defined in vitro conditions. In addition, some elongated cells spontaneously acquired a contraction capacity. Our results reinforce that the dental pulp is an important source of adult stem cells and encourage studies on therapeutic potential of mDPSC in experimental disease models. Copyright © 2011 Elsevier Ltd. All rights reserved.

  9. CD71(high) population represents primitive erythroblasts derived from mouse embryonic stem cells.

    Science.gov (United States)

    Chao, Ruihua; Gong, Xueping; Wang, Libo; Wang, Pengxiang; Wang, Yuan

    2015-01-01

    The CD71/Ter119 combination has been widely used to reflect dynamic maturation of erythrocytes in vivo. However, because CD71 is expressed on all proliferating cells, it is unclear whether it can be utilized as an erythrocyte-specific marker during differentiation of embryonic stem cells (ESCs). In this study, we revealed that a population expressing high level of CD71 (CD71(high)) during mouse ESC differentiation represented an in vitro counterpart of yolk sac-derived primitive erythroblasts (EryPs) isolated at 8.5days post coitum. In addition, these CD71(high) cells went through "maturational globin switching" and enucleated during terminal differentiation in vitro that were similar to the yolk sac-derived EryPs in vivo. We further demonstrated that the formation of CD71(high) population was regulated differentially by key factors including Scl, HoxB4, Eaf1, and Klf1. Taken together, our study provides a technical advance that allows efficient segregation of EryPs from differentiated ESCs in vitro for further understanding molecular regulation during primitive erythropoiesis. Copyright © 2014. Published by Elsevier B.V.

  10. Cytotoxic Effects of Dillapiole on Embryonic Development of Mouse Blastocysts in Vitro and in Vivo

    Directory of Open Access Journals (Sweden)

    Wen-Hsiung Chan

    2014-06-01

    Full Text Available We examined the cytotoxic effects of dillapiole, a phenylpropanoid with antileishmanial, anti-inflammatory, antifungal, and acaricidal activities, on the blastocyst stage of mouse embryos, subsequent embryonic attachment and outgrowth in vitro, and in vivo implantation via embryo transfer. Blastocysts treated with 2.5–10 μM dillapiole exhibited a significant increase in apoptosis and corresponding decrease in total cell number. Notably, the implantation success rates of blastocysts pretreated with dillapiole were lower than those of their control counterparts. Moreover, in vitro treatment with 2.5–10 μM dillapiole was associated with increased resorption of post-implantation embryos and decreased fetal weight. Our results collectively indicate that dillapiole induces apoptosis and retards early post-implantation development, both in vitro and in vivo. However, the extent to which this organic compound exerts teratogenic effects on early human development is not known at present. Further studies are required to establish effective protection strategies against the cytotoxic effects of dillapiole.

  11. Increasing mouse embryonic fibroblast cells adhesion on superhydrophilic vertically aligned carbon nanotube films

    Energy Technology Data Exchange (ETDEWEB)

    Lobo, A.O., E-mail: loboao@yahoo.com [Laboratory of Biomedical Nanotechnology (NanoBio), Instituto de Pesquisa e Desenvolvimento (IP and D), Universidade do Vale do Paraiba UniVap, Avenida Shishima Hifumi 2911, Sao Jose dos Campos, 12244-000, SP (Brazil) and Laboratory of Biomedical Vibrational Spectroscopy (LEVB), Instituto de Pesquisa e Desenvolvimento (IP and D), Universidade do Vale do Paraiba UniVap, Avenida Shishima Hifumi 2911, Sao Jose dos Campos, 12244-000, SP (Brazil); Marciano, F.R. [Laboratory of Biomedical Nanotechnology (NanoBio), Instituto de Pesquisa e Desenvolvimento (IP and D), Universidade do Vale do Paraiba UniVap, Avenida Shishima Hifumi 2911, Sao Jose dos Campos, 12244-000, SP (Brazil); Laboratory of Biomedical Vibrational Spectroscopy LEVB, Instituto de Pesquisa e Desenvolvimento (IP and D), Universidade do Vale do Paraiba (UniVap), Avenida Shishima Hifumi 2911, Sao Jose dos Campos, 12244-000, SP (Brazil); Ramos, S.C. [Laboratorio Associado de Sensores e Materiais (LAS), Instituto Nacional de Pesquisas Espaciais (INPE), Avenida dos Astronautas 1758, Sao Jose dos Campos, 12.245-970, SP (Brazil); Machado, M.M. [Centro Multidisciplinar para Investigacao Biologica na Area da Ciencia em Animais de Laboratorio (CEMIB), Universidade Estadual de Campinas (UNICAMP), Rua 05 de Junho s/no, Cidade Universitaria ' Zeferino Vaz' , 13083-877, Campinas (Brazil); Corat, E.J. [Laboratorio Associado de Sensores e Materiais (LAS), Instituto Nacional de Pesquisas Espaciais (INPE), Avenida dos Astronautas 1758, Sao Jose dos Campos, 12.245-970, SP (Brazil); Corat, M.A.F. [Centro Multidisciplinar para Investigacao Biologica na Area da Ciencia em Animais de Laboratorio (CEMIB), Universidade Estadual de Campinas (UNICAMP), Rua 05 de Junho s/no, Cidade Universitaria ' Zeferino Vaz' , 13083-877, Campinas (Brazil)

    2011-10-10

    We have analyzed the adhesion of mouse embryonic fibroblasts (MEFs) genetically modified by green fluorescence protein (GFP) gene cultured on vertically-aligned carbon nanotubes (VACNTs) after 6 days. The VACNTs films grown on Ti were obtained by microwave plasma chemical vapor deposition process using Fe catalyst and submitted to an oxygen plasma treatment, for 2 min, at 400 V and 80 mTorr, to convert them to superhydrophilic. Cellular adhesion and morphology were analyzed by scanning electron, fluorescence microscopy, and thermodynamics analysis. Characterizations of superhydrophilic VACNTs films were evaluated by contact angle and X-Ray Photoelectron Spectroscopy. Differences of crowd adhered cells, as well as their spreading on superhydrophilic VACNTs scaffolds, were evaluated using focal adhesion analysis. This study was the first to demonstrate, in real time, that the wettability of VACNTs scaffolds might have enhanced and differential adherence patterns to the MEF-GFP on VACNTs substrates. Highlights: {yields} A simple oxygen plasma treatment was used to obtain superhydrophilic CNT films. {yields} Superhydrophilic CNTs films were successfully produced by incorporation of carboxylic groups. {yields} Cellular adhesion on superhydrophilic VACNT films was analyzed in real time. {yields} Wettability of CNT films directly affects the cellular migration, proliferation and adhesion.

  12. Random mtDNA mutations modulate proliferation capacity in mouse embryonic fibroblasts

    International Nuclear Information System (INIS)

    Kukat, Alexandra; Edgar, Daniel; Bratic, Ivana; Maiti, Priyanka; Trifunovic, Aleksandra

    2011-01-01

    Highlights: → Increased mtDNA mutations in MEFs lead to high level of spontaneous immortalization. → This process is independent of endogenous ROS production. → Aerobic glycolysis significantly contributes to spontaneous immortalization of MEFs. -- Abstract: An increase in mtDNA mutation load leads to a loss of critical cells in different tissues thereby contributing to the physiological process of organismal ageing. Additionally, the accumulation of senescent cells that display changes in metabolic function might act in an active way to further disrupt the normal tissue function. We believe that this could be the important link missing in our understanding of the molecular mechanisms of premature ageing in the mtDNA mutator mice. We tested proliferation capacity of mtDNA mutator cells in vitro. When cultured in physiological levels of oxygen (3%) their proliferation capacity is somewhat lower than wild-type cells. Surprisingly, in conditions of increased oxidative stress (20% O 2 ) mtDNA mutator mouse embryonic fibroblasts exhibit continuous proliferation due to spontaneous immortalization, whereas the same conditions promote senescence in wild-type cells. We believe that an increase in aerobic glycolysis observed in mtDNA mutator mice is a major mechanism behind this process. We propose that glycolysis promotes proliferation and allows a fast turnover of metabolites, but also leads to energy crisis due to lower ATP production rate. This could lead to compromised replication and/or repair and therefore, in rare cases, might lead to mutations in tumor suppressor genes and spontaneous immortalization.

  13. Conditional mutation of Smc5 in mouse embryonic stem cells perturbs condensin localization and mitotic progression.

    Science.gov (United States)

    Pryzhkova, Marina V; Jordan, Philip W

    2016-04-15

    Correct duplication of stem cell genetic material and its appropriate segregation into daughter cells are requisites for tissue, organ and organism homeostasis. Disruption of stem cell genomic integrity can lead to developmental abnormalities and cancer. Roles of the Smc5/6 structural maintenance of chromosomes complex in pluripotent stem cell genome maintenance have not been investigated, despite its important roles in DNA synthesis, DNA repair and chromosome segregation as evaluated in other model systems. Using mouse embryonic stem cells (mESCs) with a conditional knockout allele of Smc5, we showed that Smc5 protein depletion resulted in destabilization of the Smc5/6 complex, accumulation of cells in G2 phase of the cell cycle and apoptosis. Detailed assessment of mitotic mESCs revealed abnormal condensin distribution and perturbed chromosome segregation, accompanied by irregular spindle morphology, lagging chromosomes and DNA bridges. Mutation of Smc5 resulted in retention of Aurora B kinase and enrichment of condensin on chromosome arms. Furthermore, we observed reduced levels of Polo-like kinase 1 at kinetochores during mitosis. Our study reveals crucial requirements of the Smc5/6 complex during cell cycle progression and for stem cell genome maintenance. © 2016. Published by The Company of Biologists Ltd.

  14. Femtosecond laser assisted photo-transfection and differentiation of mouse embryonic stem cells

    Science.gov (United States)

    Thobakgale, Lebogang; Manoto, Sello; Ombinda Lemboumba, Satuurnin; Maaza, Malik; Mthunzi-Kufa, Patience

    2018-02-01

    In tissue engineering research, stem cells have been used as starting material in the synthesis of mammalian cells for the treatment of various cell based diseases. This is done by manipulating the DNA content of the cells to induce a specific effect such as increased proliferation or developing a new cell type through the process of differentiation. Such controlled gene expression of stem cells is achieved by the method of transfection, where exogenous plasmid deoxyribonucleic acid (pDNA) is inserted into a stem cell using chemical, viral or physical methods. In this research, we used femtosecond (fs) laser pulses from a home-build microscope system to perforate the cellular membrane and allow entry of selected pDNA to alter the behaviour of mouse embryonic stem cells (mESCs). In one set of experiments, we induce fluorescence on mESCs using green fluorescence protein plasmid (pGFP) while in other tests; differentiation of mESCs into endoderm cells is performed using Sox-17 plasmid DNA (pSox-17). Primitive endoderm formation was thereafter confirmed using polymerase chain reactions (PCR) and the Sox-17 primer. Cell viability studies using adenosine triphosphate were also conducted. From the data, it was concluded that the photo-transfection method is biocompatible since it was able to induce fluorescence in mESCs. Secondly, it was confirmed that Sox-17 was photo-transfected successfully using 6 μW laser power, 128 fs pulses and 1kHz pulse repetition rate.

  15. Efficient Differentiation of Mouse Embryonic Stem Cells into Insulin-Producing Cells

    Directory of Open Access Journals (Sweden)

    Szu-Hsiu Liu

    2012-01-01

    Full Text Available Embryonic stem (ES cells are a potential source of a variety of differentiated cells for cell therapy, drug discovery, and toxicology screening. Here, we present an efficacy strategy for the differentiation of mouse ES cells into insulin-producing cells (IPCs by a two-step differentiation protocol comprising of (i the formation of definitive endoderm in monolayer culture by activin A, and (ii this monolayer endoderm being induced to differentiate into IPCs by nicotinamide, insulin, and laminin. Differentiated cells can be obtained within approximately 7 days. The differentiation IPCs combined application of RT-PCR, ELISA, and immunofluorescence to characterize phenotypic and functional properties. In our study, we demonstrated that IPCs produced pancreatic transcription factors, endocrine progenitor marker, definitive endoderm, pancreatic β-cell markers, and Langerhans α and δ cells. The IPCs released insulin in a manner that was dose dependent upon the amount of glucose added. These techniques may be able to be applied to human ES cells, which would have very important ramifications for treating human disease.

  16. Neural differentiation of mouse embryonic stem cells as a tool to assess developmental neurotoxicity in vitro.

    Science.gov (United States)

    Visan, Anke; Hayess, Katrin; Sittner, Dana; Pohl, Elena E; Riebeling, Christian; Slawik, Birgitta; Gulich, Konrad; Oelgeschläger, Michael; Luch, Andreas; Seiler, Andrea E M

    2012-10-01

    Mouse embryonic stem cells (mESCs) represent an attractive cellular system for in vitro studies in developmental biology as well as toxicology because of their potential to differentiate into all fetal cell lineages. The present study aims to establish an in vitro system for developmental neurotoxicity testing employing mESCs. We developed a robust and reproducible protocol for fast and efficient differentiation of the mESC line D3 into neural cells, optimized with regard to chemical testing. Morphological examination and immunocytochemical staining confirmed the presence of different neural cell types, including neural progenitors, neurons, astrocytes, oligodendrocytes, and radial glial cells. Neurons derived from D3 cells expressed the synaptic proteins PSD95 and synaptophysin, and the neurotransmitters serotonin and γ-aminobutyric acid. Calcium ion imaging revealed the presence of functionally active glutamate and dopamine receptors. In addition, flow cytometry analysis of the neuron-specific marker protein MAP2 on day 12 after induction of differentiation demonstrated a concentration dependent effect of the neurodevelopmental toxicants methylmercury chloride, chlorpyrifos, and lead acetate on neuronal differentiation. The current study shows that D3 mESCs differentiate efficiently into neural cells involving a neurosphere-like state and that this system is suitable to detect adverse effects of neurodevelopmental toxicants. Therefore, we propose that the protocol for differentiation of mESCs into neural cells described here could constitute one component of an in vitro testing strategy for developmental neurotoxicity. Copyright © 2012 Elsevier Inc. All rights reserved.

  17. Suppression of Red Blood Cell Autofluorescence for Immunocytochemistry on Fixed Embryonic Mouse Tissue.

    Science.gov (United States)

    Whittington, Niteace C; Wray, Susan

    2017-10-23

    Autofluorescence is a problem that interferes with immunofluorescent staining and complicates data analysis. Throughout the mouse embryo, red blood cells naturally fluoresce across multiple wavelengths, spanning the emission and excitation spectra of many commonly used fluorescent reporters, including antibodies, dyes, stains, probes, and transgenic proteins, making it difficult to distinguish assay fluorescence from endogenous fluorescence. Several tissue treatment methods have been developed to bypass this issue with varying degrees of success. Sudan Black B dye has been commonly used to quench autofluorescence, but can also introduce background fluorescence. Here we present a protocol for an alternative called TrueBlack Lipofuscin Autofluorescence Quencher. The protocol described in this unit demonstrates how TrueBlack efficiently quenches red blood cell autofluorescence across red and green wavelengths in fixed embryonic tissue without interfering with immunofluorescent signal intensity or introducing background staining. We also identify optimal incubation, concentration, and multiple usage conditions for routine immunofluorescence microscopy. © 2017 by John Wiley & Sons, Inc. Copyright © 2017 John Wiley & Sons, Inc.

  18. A chronological expression profile of gene activity during embryonic mouse brain development.

    Science.gov (United States)

    Goggolidou, P; Soneji, S; Powles-Glover, N; Williams, D; Sethi, S; Baban, D; Simon, M M; Ragoussis, I; Norris, D P

    2013-12-01

    The brain is a functionally complex organ, the patterning and development of which are key to adult health. To help elucidate the genetic networks underlying mammalian brain patterning, we conducted detailed transcriptional profiling during embryonic development of the mouse brain. A total of 2,400 genes were identified as showing differential expression between three developmental stages. Analysis of the data identified nine gene clusters to demonstrate analogous expression profiles. A significant group of novel genes of as yet undiscovered biological function were detected as being potentially relevant to brain development and function, in addition to genes that have previously identified roles in the brain. Furthermore, analysis for genes that display asymmetric expression between the left and right brain hemispheres during development revealed 35 genes as putatively asymmetric from a combined data set. Our data constitute a valuable new resource for neuroscience and neurodevelopment, exposing possible functional associations between genes, including novel loci, and encouraging their further investigation in human neurological and behavioural disorders.

  19. Cytotoxic Effect of Iron Oxide Nanoparticles on Mouse Embryonic Stem Cells by MTT Assay

    Directory of Open Access Journals (Sweden)

    Homa Mohseni Kouchesfehani

    2016-07-01

    Full Text Available Background: Despite the wide range of applications, there is a serious lack of information on the impact of the nanoparticles on human health and the environment. The present study was done to determine the range of dangerous concentrations of iron oxide nanoparticle and their effects on mouse embryonic stem cells. Methods: Iron oxide nanoparticles with less than 20 nanometers diameter were encapsulated by a PEG-phospholipid. The suspension of iron oxide nanoparticles was prepared using the culture media and cell viability was determined by MTT assay. Results: MTT assay was used to examine the cytotoxicity of iron oxide nanoparticle s. Royan B1 cells were treated with medium containing different concentrations (10, 20, 30, 40, 50, and 60µg/ml of the iron oxide nanoparticle. Cell viability was determined at 12 and 24 hours after treatment which showed significant decreases when concentration and time period increased. Conclusion: The main mechanism of nanoparticles action is still unknown, but in vivo and in vitro studies in different environments suggest that they are capable of producing reactive oxygen species (ROS. Therefore, they may have an effect on the concentration of intracellular calcium, activation of transcription factors, and changes in cytokine. The results of this study show that the higher concentration and duration of treatment of cells with iron oxide nanoparticles increase the rate of cell death.

  20. Comparing the mechanical influence of vinculin, focal adhesion kinase and p53 in mouse embryonic fibroblasts

    International Nuclear Information System (INIS)

    Klemm, Anna H.; Diez, Gerold; Alonso, Jose-Luis; Goldmann, Wolfgang H.

    2009-01-01

    Cytoskeletal reorganization is an ongoing process when cells adhere, move or invade extracellular substrates. The cellular force generation and transmission are determined by the intactness of the actomyosin-(focal adhesion complex)-integrin connection. We investigated the intracellular course of action in mouse embryonic fibroblasts deficient in the focal adhesion proteins vinculin and focal adhesion kinase (FAK) and the nuclear matrix protein p53 using magnetic tweezer and nanoparticle tracking techniques. Results show that the lack of these proteins decrease cellular stiffness and affect cell rheological behavior. The decrease in cellular binding strength was higher in FAK- to vinculin-deficient cells, whilst p53-deficient cells showed no effect compared to wildtype cells. The intracellular cytoskeletal activity was lowest in wildtype cells, but increased in the following order when cells lacked FAK+p53 > p53 > vinculin. In summary, cell mechanical processes are differently affected by the focal adhesion proteins vinculin and FAK than by the nuclear matrix protein, p53.

  1. Essential role of chromatin remodeling protein Bptf in early mouse embryos and embryonic stem cells.

    Directory of Open Access Journals (Sweden)

    Joseph Landry

    2008-10-01

    Full Text Available We have characterized the biological functions of the chromatin remodeling protein Bptf (Bromodomain PHD-finger Transcription Factor, the largest subunit of NURF (Nucleosome Remodeling Factor in a mammal. Bptf mutants manifest growth defects at the post-implantation stage and are reabsorbed by E8.5. Histological analyses of lineage markers show that Bptf(-/- embryos implant but fail to establish a functional distal visceral endoderm. Microarray analysis at early stages of differentiation has identified Bptf-dependent gene targets including homeobox transcriptions factors and genes essential for the development of ectoderm, mesoderm, and both definitive and visceral endoderm. Differentiation of Bptf(-/- embryonic stem cell lines into embryoid bodies revealed its requirement for development of mesoderm, endoderm, and ectoderm tissue lineages, and uncovered many genes whose activation or repression are Bptf-dependent. We also provide functional and physical links between the Bptf-containing NURF complex and the Smad transcription factors. These results suggest that Bptf may co-regulate some gene targets of this pathway, which is essential for establishment of the visceral endoderm. We conclude that Bptf likely regulates genes and signaling pathways essential for the development of key tissues of the early mouse embryo.

  2. Induction of superficial cortical layer neurons from mouse embryonic stem cells by valproic acid.

    Science.gov (United States)

    Juliandi, Berry; Abematsu, Masahiko; Sanosaka, Tsukasa; Tsujimura, Keita; Smith, Austin; Nakashima, Kinichi

    2012-01-01

    Within the developing mammalian cortex, neural progenitors first generate deep-layer neurons and subsequently more superficial-layer neurons, in an inside-out manner. It has been reported recently that mouse embryonic stem cells (mESCs) can, to some extent, recapitulate cortical development in vitro, with the sequential appearance of neurogenesis markers resembling that in the developing cortex. However, mESCs can only recapitulate early corticogenesis; superficial-layer neurons, which are normally produced in later developmental periods in vivo, are under-represented. This failure of mESCs to reproduce later corticogenesis in vitro implies the existence of crucial factor(s) that are absent or uninduced in existing culture systems. Here we show that mESCs can give rise to superficial-layer neurons efficiently when treated with valproic acid (VPA), a histone deacetylase inhibitor. VPA treatment increased the production of Cux1-positive superficial-layer neurons, and decreased that of Ctip2-positive deep-layer neurons. These results shed new light on the mechanisms of later corticogenesis. Copyright © 2011 Elsevier Ireland Ltd and the Japan Neuroscience Society. All rights reserved.

  3. Generation of organized germ layers from a single mouse embryonic stem cell.

    Science.gov (United States)

    Poh, Yeh-Chuin; Chen, Junwei; Hong, Ying; Yi, Haiying; Zhang, Shuang; Chen, Junjian; Wu, Douglas C; Wang, Lili; Jia, Qiong; Singh, Rishi; Yao, Wenting; Tan, Youhua; Tajik, Arash; Tanaka, Tetsuya S; Wang, Ning

    2014-05-30

    Mammalian inner cell mass cells undergo lineage-specific differentiation into germ layers of endoderm, mesoderm and ectoderm during gastrulation. It has been a long-standing challenge in developmental biology to replicate these organized germ layer patterns in culture. Here we present a method of generating organized germ layers from a single mouse embryonic stem cell cultured in a soft fibrin matrix. Spatial organization of germ layers is regulated by cortical tension of the colony, matrix dimensionality and softness, and cell-cell adhesion. Remarkably, anchorage of the embryoid colony from the 3D matrix to collagen-1-coated 2D substrates of ~1 kPa results in self-organization of all three germ layers: ectoderm on the outside layer, mesoderm in the middle and endoderm at the centre of the colony, reminiscent of generalized gastrulating chordate embryos. These results suggest that mechanical forces via cell-matrix and cell-cell interactions are crucial in spatial organization of germ layers during mammalian gastrulation. This new in vitro method could be used to gain insights on the mechanisms responsible for the regulation of germ layer formation.

  4. Biocompatibility effects of biologically synthesized graphene in primary mouse embryonic fibroblast cells

    Science.gov (United States)

    Gurunathan, Sangiliyandi; Han, Jae Woong; Eppakayala, Vasuki; Dayem, Ahmed Abdal; Kwon, Deug-Nam; Kim, Jin-Hoi

    2013-09-01

    Due to unique properties and unlimited possible applications, graphene has attracted abundant interest in the areas of nanobiotechnology. Recently, much work has focused on the synthesis and properties of graphene. Here we show that a successful reduction of graphene oxide (GO) using spinach leaf extract (SLE) as a simultaneous reducing and stabilizing agent. The as-prepared SLE-reduced graphene oxide (S-rGO) was characterized by ultraviolet-visible spectroscopy and Fourier transform infrared spectroscopy. Dynamic light scattering technique was used to determine the average size of GO and S-rGO. Scanning electron microscopy and atomic force microscopy images provide clear surface morphological evidence for the formation of graphene. The resulting S-rGO has a mostly single-layer structure, is stable, and has significant water solubility. In addition, the biocompatibility of graphene was investigated using cell viability, leakage of lactate dehydrogenase and alkaline phosphatase activity in primary mouse embryonic fibroblast (PMEFs) cells. The results suggest that the biologically synthesized graphene has significant biocompatibility with PMEF cells, even at a higher concentration of 100 μg/mL. This method uses a `green', natural reductant and is free of additional stabilizing reagents; therefore, it is an environmentally friendly, simple, and cost-effective method for the fabrication of soluble graphene. This study could open up a promising view for substitution of hydrazine by a safe, biocompatible, and powerful reduction for the efficient deoxygenation of GO, especially in large-scale production and potential biomedical applications.

  5. Highly efficient CRISPR/HDR-mediated knock-in for mouse embryonic stem cells and zygotes.

    Science.gov (United States)

    Wang, Bangmei; Li, Kunyu; Wang, Amy; Reiser, Michelle; Saunders, Thom; Lockey, Richard F; Wang, Jia-Wang

    2015-10-01

    The clustered regularly interspaced short palindromic repeat (CRISPR) gene editing technique, based on the non-homologous end-joining (NHEJ) repair pathway, has been used to generate gene knock-outs with variable sizes of small insertion/deletions with high efficiency. More precise genome editing, either the insertion or deletion of a desired fragment, can be done by combining the homology-directed-repair (HDR) pathway with CRISPR cleavage. However, HDR-mediated gene knock-in experiments are typically inefficient, and there have been no reports of successful gene knock-in with DNA fragments larger than 4 kb. Here, we describe the targeted insertion of large DNA fragments (7.4 and 5.8 kb) into the genomes of mouse embryonic stem (ES) cells and zygotes, respectively, using the CRISPR/HDR technique without NHEJ inhibitors. Our data show that CRISPR/HDR without NHEJ inhibitors can result in highly efficient gene knock-in, equivalent to CRISPR/HDR with NHEJ inhibitors. Although NHEJ is the dominant repair pathway associated with CRISPR-mediated double-strand breaks (DSBs), and biallelic gene knock-ins are common, NHEJ and biallelic gene knock-ins were not detected. Our results demonstrate that efficient targeted insertion of large DNA fragments without NHEJ inhibitors is possible, a result that should stimulate interest in understanding the mechanisms of high efficiency CRISPR targeting in general.

  6. Sp5 induces the expression of Nanog to maintain mouse embryonic stem cell self-renewal.

    Science.gov (United States)

    Tang, Ling; Wang, Manman; Liu, Dahai; Gong, Mengting; Ying, Qi-Long; Ye, Shoudong

    2017-01-01

    Activation of signal transducer and activator of transcription 3 (STAT3) by leukemia inhibitory factor (LIF) maintains mouse embryonic stem cell (mESC) self-renewal. Our previous study showed that trans-acting transcription factor 5 (Sp5), an LIF/STAT3 downstream target, supports mESC self-renewal. However, the mechanism by which Sp5 exerts these effects remains elusive. Here, we found that Nanog is a direct target of Sp5 and mediates the self-renewal-promoting effect of Sp5 in mESCs. Overexpression of Sp5 induced Nanog expression, while knockdown or knockout of Sp5 decreased the Nanog level. Moreover, chromatin immunoprecipitation (ChIP) assays showed that Sp5 directly bound to the Nanog promoter. Functional studies revealed that knockdown of Nanog eliminated the mESC self-renewal-promoting ability of Sp5. Finally, we demonstrated that the self-renewal-promoting function of Sp5 was largely dependent on its zinc finger domains. Taken together, our study provides unrecognized functions of Sp5 in mESCs and will expand our current understanding of the regulation of mESC pluripotency.

  7. RYBP and Cbx7 Define Specific Biological Functions of Polycomb Complexes in Mouse Embryonic Stem Cells

    Directory of Open Access Journals (Sweden)

    Lluis Morey

    2013-01-01

    Full Text Available The Polycomb repressive complex 1 (PRC1 is required for decisions of stem cell fate. In mouse embryonic stem cells (ESCs, two major variations of PRC1 complex, defined by the mutually exclusive presence of Cbx7 or RYBP, have been identified. Here, we show that although the genomic localization of the Cbx7- and RYBP-containing PRC1 complexes overlaps in certain genes, it can also be mutually exclusive. At the molecular level, Cbx7 is necessary for recruitment of Ring1B to chromatin, whereas RYBP enhances the PRC1 enzymatic activity. Genes occupied by RYBP show lower levels of Ring1B and H2AK119ub and are consequently more highly transcribed than those bound by Cbx7. At the functional level, we show that genes occupied by RYBP are primarily involved in the regulation of metabolism and cell-cycle progression, whereas those bound by Cbx7 predominantly control early-lineage commitment of ESCs. Altogether, our results indicate that different PRC1 subtypes establish a complex pattern of gene regulation that regulates common and nonoverlapping aspects of ESC pluripotency and differentiation.

  8. Differentiate or Die: 3-Bromopyruvate and Pluripotency in Mouse Embryonic Stem Cells.

    Directory of Open Access Journals (Sweden)

    Ana Sofia Rodrigues

    Full Text Available Pluripotent embryonic stem cells grown under standard conditions (ESC have a markedly glycolytic profile, which is shared with many different types of cancer cells. Thus, some therapeutic strategies suggest that pharmacologically shifting cancer cells towards an oxidative phenotype, using glycolysis inhibitors, may reduce cancer aggressiveness. Given the metabolic parallels between cancer and stemness would chemotherapeutical agents have an effect on pluripotency, and could a strategy involving these agents be envisioned to modulate stem cell fate in an accessible manner? In this manuscript we attempted to determine the effects of 3-bromopyruvate (3BrP in pluripotency. Although it has other intracellular targets, this compound is a potent inhibitor of glycolysis enzymes thought to be important to maintain a glycolytic profile. The goal was also to determine if we could contribute towards a pharmacologically accessible metabolic strategy to influence cell differentiation.Mouse embryonic stem cells (mESC grown under standard pluripotency conditions (in the presence of Leukemia Inducing Factor- LIF were treated with 3BrP. As a positive control for differentiation other mESCs were grown without LIF. Overall our results demonstrate that 3BrP negatively affects pluripotency, forcing cells to become less glycolytic and with more active mitochondria. These changes in metabolism are correlated with increased differentiation, even under pluripotency conditions (i.e. in the presence of LIF. However, 3BrP also significantly impaired cell function, and may have other roles besides affecting the metabolic profile of mESCs.Treatment of mESCs with 3BrP triggered a metabolic switch and loss of pluripotency, even in the presence of LIF. Interestingly, the positive control for differentiation allowed for a distinction between 3BrP effects and changes associated with spontaneous differentiation/loss of pluripotency in the absence of LIF. Additionally, there was a

  9. Differentiate or Die: 3-Bromopyruvate and Pluripotency in Mouse Embryonic Stem Cells.

    Science.gov (United States)

    Rodrigues, Ana Sofia; Pereira, Sandro L; Correia, Marcelo; Gomes, Andreia; Perestrelo, Tânia; Ramalho-Santos, João

    2015-01-01

    Pluripotent embryonic stem cells grown under standard conditions (ESC) have a markedly glycolytic profile, which is shared with many different types of cancer cells. Thus, some therapeutic strategies suggest that pharmacologically shifting cancer cells towards an oxidative phenotype, using glycolysis inhibitors, may reduce cancer aggressiveness. Given the metabolic parallels between cancer and stemness would chemotherapeutical agents have an effect on pluripotency, and could a strategy involving these agents be envisioned to modulate stem cell fate in an accessible manner? In this manuscript we attempted to determine the effects of 3-bromopyruvate (3BrP) in pluripotency. Although it has other intracellular targets, this compound is a potent inhibitor of glycolysis enzymes thought to be important to maintain a glycolytic profile. The goal was also to determine if we could contribute towards a pharmacologically accessible metabolic strategy to influence cell differentiation. Mouse embryonic stem cells (mESC) grown under standard pluripotency conditions (in the presence of Leukemia Inducing Factor- LIF) were treated with 3BrP. As a positive control for differentiation other mESCs were grown without LIF. Overall our results demonstrate that 3BrP negatively affects pluripotency, forcing cells to become less glycolytic and with more active mitochondria. These changes in metabolism are correlated with increased differentiation, even under pluripotency conditions (i.e. in the presence of LIF). However, 3BrP also significantly impaired cell function, and may have other roles besides affecting the metabolic profile of mESCs. Treatment of mESCs with 3BrP triggered a metabolic switch and loss of pluripotency, even in the presence of LIF. Interestingly, the positive control for differentiation allowed for a distinction between 3BrP effects and changes associated with spontaneous differentiation/loss of pluripotency in the absence of LIF. Additionally, there was a slight

  10. Selective attention without a neocortex.

    Science.gov (United States)

    Krauzlis, Richard J; Bogadhi, Amarender R; Herman, James P; Bollimunta, Anil

    2018-05-01

    Selective attention refers to the ability to restrict neural processing and behavioral responses to a relevant subset of available stimuli, while simultaneously excluding other valid stimuli from consideration. In primates and other mammals, descriptions of this ability typically emphasize the neural processing that takes place in the cerebral neocortex. However, non-mammals such as birds, reptiles, amphibians and fish, which completely lack a neocortex, also have the ability to selectively attend. In this article, we survey the behavioral evidence for selective attention in non-mammals, and review the midbrain and forebrain structures that are responsible. The ancestral forms of selective attention are presumably selective orienting behaviors, such as prey-catching and predator avoidance. These behaviors depend critically on a set of subcortical structures, including the optic tectum (OT), thalamus and striatum, that are highly conserved across vertebrate evolution. In contrast, the contributions of different pallial regions in the forebrain to selective attention have been subject to more substantial changes and reorganization. This evolutionary perspective makes plain that selective attention is not a function achieved de novo with the emergence of the neocortex, but instead is implemented by circuits accrued and modified over hundreds of millions of years, beginning well before the forebrain contained a neocortex. Determining how older subcortical circuits interact with the more recently evolved components in the neocortex will likely be crucial for understanding the complex properties of selective attention in primates and other mammals, and for identifying the etiology of attention disorders. Published by Elsevier Ltd.

  11. Nat1 promotes translation of specific proteins that induce differentiation of mouse embryonic stem cells.

    Science.gov (United States)

    Sugiyama, Hayami; Takahashi, Kazutoshi; Yamamoto, Takuya; Iwasaki, Mio; Narita, Megumi; Nakamura, Masahiro; Rand, Tim A; Nakagawa, Masato; Watanabe, Akira; Yamanaka, Shinya

    2017-01-10

    Novel APOBEC1 target 1 (Nat1) (also known as "p97," "Dap5," and "Eif4g2") is a ubiquitously expressed cytoplasmic protein that is homologous to the C-terminal two thirds of eukaryotic translation initiation factor 4G (Eif4g1). We previously showed that Nat1-null mouse embryonic stem cells (mES cells) are resistant to differentiation. In the current study, we found that NAT1 and eIF4G1 share many binding proteins, such as the eukaryotic translation initiation factors eIF3 and eIF4A and ribosomal proteins. However, NAT1 did not bind to eIF4E or poly(A)-binding proteins, which are critical for cap-dependent translation initiation. In contrast, compared with eIF4G1, NAT1 preferentially interacted with eIF2, fragile X mental retardation proteins (FMR), and related proteins and especially with members of the proline-rich and coiled-coil-containing protein 2 (PRRC2) family. We also found that Nat1-null mES cells possess a transcriptional profile similar, although not identical, to the ground state, which is established in wild-type mES cells when treated with inhibitors of the ERK and glycogen synthase kinase 3 (GSK3) signaling pathways. In Nat1-null mES cells, the ERK pathway is suppressed even without inhibitors. Ribosome profiling revealed that translation of mitogen-activated protein kinase kinase kinase 3 (Map3k3) and son of sevenless homolog 1 (Sos1) is suppressed in the absence of Nat1 Forced expression of Map3k3 induced differentiation of Nat1-null mES cells. These data collectively show that Nat1 is involved in the translation of proteins that are required for cell differentiation.

  12. Phosphatidylinositol 3,4,5-trisphosphate modulation in SHIP2-deficient mouse embryonic fibroblasts.

    Science.gov (United States)

    Blero, Daniel; Zhang, Jing; Pesesse, Xavier; Payrastre, Bernard; Dumont, Jacques E; Schurmans, Stéphane; Erneux, Christophe

    2005-05-01

    SHIP2, the ubiquitous SH2 domain containing inositol 5-phosphatase, includes a series of protein interacting domains and has the ability to dephosphorylate phosphatidylinositol 3,4,5-trisphosphate [PtdIns(3,4,5)P(3)]in vitro. The present study, which was undertaken to evaluate the impact of SHIP2 on PtdIns(3,4,5)P(3) levels, was performed in a mouse embryonic fibroblast (MEF) model using SHIP2 deficient (-/-) MEF cells derived from knockout mice. PtdIns(3,4,5)P(3) was upregulated in serum stimulated -/- MEF cells as compared to +/+ MEF cells. Although the absence of SHIP2 had no effect on basal PtdIns(3,4,5)P(3) levels, we show here that this lipid was significantly upregulated in SHIP2 -/- cells but only after short-term (i.e. 5-10 min) incubation with serum. The difference in PtdIns(3,4,5)P(3) levels in heterozygous fibroblast cells was intermediate between the +/+ and the -/- cells. In our model, insulin-like growth factor-1 stimulation did not show this upregulation. Serum stimulated phosphoinositide 3-kinase (PI 3-kinase) activity appeared to be comparable between +/+ and -/- cells. Moreover, protein kinase B, but not mitogen activated protein kinase activity, was also potentiated in SHIP2 deficient cells stimulated by serum. The upregulation of protein kinase B activity in serum stimulated cells was totally reversed in the presence of the PI 3-kinase inhibitor LY-294002, in both +/+ and -/- cells. Altogether, these data establish a link between SHIP2 and the acute control of PtdIns(3,4,5)P(3) levels in intact cells.

  13. Characterization and comparison of osteoblasts derived from mouse embryonic stem cells and induced pluripotent stem cells.

    Science.gov (United States)

    Ma, Ming-San; Kannan, Vishnu; de Vries, Anneriek E; Czepiel, Marcin; Wesseling, Evelyn M; Balasubramaniyan, Veerakumar; Kuijer, Roel; Vissink, Arjan; Copray, Sjef C V M; Raghoebar, Gerry M

    2017-01-01

    New developments in stem cell biology offer alternatives for the reconstruction of critical-sized bone defects. One of these developments is the use of induced pluripotent stem (iPS) cells. These stem cells are similar to embryonic stem (ES) cells, but can be generated from adult somatic cells and therefore do not raise ethical concerns. Proper characterization of iPS-derived osteoblasts is important for future development of safe clinical applications of these cells. For this reason, we differentiated mouse ES and iPS cells toward osteoblasts using osteogenic medium and compared their functionality. Immunocytochemical analysis showed significant expression of bone markers (osteocalcin and collagen type I) in osteoblasts differentiated from ES and iPS cells on days 7 and 30. An in vitro mineralization assay confirmed the functionality of osteogenically differentiated ES and iPS cells. Gene expression arrays focusing on osteogenic differentiation were performed in order to compare the gene expression pattern in both differentiated and undifferentiated ES cells and iPS cells. We observed a significant upregulation of osteogenesis-related genes such as Runx2, osteopontin, collagen type I, Tnfsf11, Csf1, and alkaline phosphatase upon osteogenic differentiation of the ES and iPS cells. We further validated the expression of key osteogenic genes Runx2, osteopontin, osteocalcin, collagen type I, and osterix in both differentiated and undifferentiated ES and iPS cells by means of quantified real-time polymerase chain reaction. We conclude that ES and iPS cells are similar in their osteogenic differentiation capacities, as well as in their gene expression patterns.

  14. Single cell lineage analysis of mouse embryonic stem cells at the exit from pluripotency

    Directory of Open Access Journals (Sweden)

    Jamie Trott

    2013-08-01

    Understanding how interactions between extracellular signalling pathways and transcription factor networks influence cellular decision making will be crucial for understanding mammalian embryogenesis and for generating specialised cell types in vitro. To this end, pluripotent mouse Embryonic Stem (mES cells have proven to be a useful model system. However, understanding how transcription factors and signalling pathways affect decisions made by individual cells is confounded by the fact that measurements are generally made on groups of cells, whilst individual mES cells differentiate at different rates and towards different lineages, even in conditions that favour a particular lineage. Here we have used single-cell measurements of transcription factor expression and Wnt/β-catenin signalling activity to investigate their effects on lineage commitment decisions made by individual cells. We find that pluripotent mES cells exhibit differing degrees of heterogeneity in their expression of important regulators from pluripotency, depending on the signalling environment to which they are exposed. As mES cells differentiate, downregulation of Nanog and Oct4 primes cells for neural commitment, whilst loss of Sox2 expression primes cells for primitive streak commitment. Furthermore, we find that Wnt signalling acts through Nanog to direct cells towards a primitive streak fate, but that transcriptionally active β-catenin is associated with both neural and primitive streak commitment. These observations confirm and extend previous suggestions that pluripotency genes influence lineage commitment and demonstrate how their dynamic expression affects the direction of lineage commitment, whilst illustrating two ways in which the Wnt signalling pathway acts on this network during cell fate assignment.

  15. The effects of silver nanoparticles on mouse embryonic stem cell self-renewal and proliferation

    Directory of Open Access Journals (Sweden)

    Pavan Rajanahalli

    2015-01-01

    Full Text Available Silver nanoparticles (AgNPs are gaining rapid popularity in many commonly used medical and commercial products for their unique anti-bacterial properties. The molecular mechanisms of effects of AgNPs on stem cell self-renewal and proliferation have not yet been well understood. The aim of the work is to use mouse embryonic stem cells (mESCs as a cellular model to evaluate the toxicity of AgNPs. mESC is a very special cell type which has self-renewal and differentiation properties. The objective of this project is to determine the effects of AgNPs with different surface chemical compositions on the self-renewal and cell cycle of mESCs. Two different surface chemical compositions of AgNPs, polysaccharide-coated and hydrocarbon-coated, were used to test their toxic effects on self-renewal and proliferation of mESCs. The results indicated that both polysaccharide-coated and hydrocarbon-coated AgNPs changed the cell morphology of mESCs. Cell cycle analysis indicated that AgNPs induced mESCs cell cycle arrest at G1 and S phases through inhibition of the hyperphosphorylation of Retinoblastoma (Rb protein. Furthermore, AgNPs exposure reduced Oct4A isoform expression which is responsible for the pluripotency of mESCs, and induced the expression of several isoforms OCT4B-265, OCT4B-190, OCT4B-164 which were suggested involved in stem cell stresses responses. In addition, the evidence of reactive oxygen species (ROS production with two different surface chemical compositions of AgNPs supported our hypothesis that the toxic effect AgNPs exposure is due to overproduction of ROS which altered the gene expression and protein modifications. Polysaccharide coating reduced ROS production, and thus reduced the AgNPs toxicity.

  16. Transient inhibition of cell proliferation does not compromise self-renewal of mouse embryonic stem cells.

    Science.gov (United States)

    Wang, Ruoxing; Guo, Yan-Lin

    2012-10-01

    Embryonic stem cells (ESCs) have unlimited capacity for self-renewal and can differentiate into various cell types when induced. They also have an unusual cell cycle control mechanism driven by constitutively active cyclin dependent kinases (Cdks). In mouse ESCs (mESCs). It is proposed that the rapid cell proliferation could be a necessary part of mechanisms that maintain mESC self-renewal and pluripotency, but this hypothesis is not in line with the finding in human ESCs (hESCs) that the length of the cell cycle is similar to differentiated cells. Therefore, whether rapid cell proliferation is essential for the maintenance of mESC state remains unclear. We provide insight into this uncertainty through chemical intervention of mESC cell cycle. We report here that inhibition of Cdks with olomoucine II can dramatically slow down cell proliferation of mESCs with concurrent down-regulation of cyclin A, B and E, and the activation of the Rb pathway. However, mESCs display can recover upon the removal of olomoucine II and are able to resume normal cell proliferation without losing self-renewal and pluripotency, as demonstrated by the expression of ESC markers, colony formation, embryoid body formation, and induced differentiation. We provide a mechanistic explanation for these observations by demonstrating that Oct4 and Nanog, two major transcription factors that play critical roles in the maintenance of ESC properties, are up-regulated via de novo protein synthesis when the cells are exposed to olomoucine II. Together, our data suggest that short-term inhibition of cell proliferation does not compromise the basic properties of mESCs. Copyright © 2012 Elsevier Inc. All rights reserved.

  17. Endogenous production of fibronectin is required for self-renewal of cultured mouse embryonic stem cells.

    Science.gov (United States)

    Hunt, Geoffrey C; Singh, Purva; Schwarzbauer, Jean E

    2012-09-10

    Pluripotent cells are attached to the extracellular matrix (ECM) as they make cell fate decisions within the stem cell niche. Here we show that the ubiquitous ECM protein fibronectin is required for self-renewal decisions by cultured mouse embryonic stem (mES) cells. Undifferentiated mES cells produce fibronectin and assemble a fibrillar matrix. Increasing the level of substrate fibronectin increased cell spreading and integrin receptor signaling through focal adhesion kinase, while concomitantly inducing the loss of Nanog and Oct4 self-renewal markers. Conversely, reducing fibronectin production by mES cells growing on a feeder-free gelatin substrate caused loss of cell adhesion, decreased integrin signaling, and decreased expression of self-renewal markers. These effects were reversed by providing the cells with exogenous fibronectin, thereby restoring adhesion to the gelatin substrate. Interestingly, mES cells do not adhere directly to the gelatin substrate, but rather adhere indirectly through gelatin-bound fibronectin, which facilitates self-renewal via its effects on cell adhesion. These results provide new insights into the mechanism of regulation of self-renewal by growth on a gelatin-coated surface. The effects of increasing or decreasing fibronectin levels show that self-renewal depends on an intermediate level of cell-fibronectin interactions. By providing cell adhesive signals that can act with other self-renewal factors to maintain mES cell pluripotency, fibronectin is therefore a necessary component of the self-renewal signaling pathway in culture. Copyright © 2012 Elsevier Inc. All rights reserved.

  18. 14-3-3σ regulates β-catenin-mediated mouse embryonic stem cell proliferation by sequestering GSK-3β.

    Directory of Open Access Journals (Sweden)

    Tzu-Ching Chang

    Full Text Available Pluripotent embryonic stem cells are considered to be an unlimited cell source for tissue regeneration and cell-based therapy. Investigating the molecular mechanism underlying the regulation of embryonic stem cell expansion is thus important. 14-3-3 proteins are implicated in controlling cell division, signaling transduction and survival by interacting with various regulatory proteins. However, the function of 14-3-3 in embryonic stem cell proliferation remains unclear.In this study, we show that all seven 14-3-3 isoforms were detected in mouse embryonic stem cells. Retinoid acid suppressed selectively the expression of 14-3-3σ isoform. Knockdown of 14-3-3σ with siRNA reduced embryonic stem cell proliferation, while only 14-3-3σ transfection increased cell growth and partially rescued retinoid acid-induced growth arrest. Since the growth-enhancing action of 14-3-3σ was abrogated by β-catenin knockdown, we investigated the influence of 14-3-3σ overexpression on β-catenin/GSK-3β. 14-3-3σ bound GSK-3β and increased GSK-3β phosphorylation in a PI-3K/Akt-dependent manner. It disrupted β-catenin binding by the multiprotein destruction complex. 14-3-3σ overexpression attenuated β-catenin phosphorylation and rescued the decline of β-catenin induced by retinoid acid. Furthermore, 14-3-3σ enhanced Wnt3a-induced β-catenin level and GSK-3β phosphorylation. DKK, an inhibitor of Wnt signaling, abolished Wnt3a-induced effect but did not interfere GSK-3β/14-3-3σ binding.Our findings show for the first time that 14-3-3σ plays an important role in regulating mouse embryonic stem cell proliferation by binding and sequestering phosphorylated GSK-3β and enhancing Wnt-signaled GSK-3β inactivation. 14-3-3σ is a novel target for embryonic stem cell expansion.

  19. Mouse embryonic stem cells, but not somatic cells, predominantly use homologous recombination to repair double-strand DNA breaks.

    Science.gov (United States)

    Tichy, Elisia D; Pillai, Resmi; Deng, Li; Liang, Li; Tischfield, Jay; Schwemberger, Sandy J; Babcock, George F; Stambrook, Peter J

    2010-11-01

    Embryonic stem (ES) cells give rise to all cell types of an organism. Since mutations at this embryonic stage would affect all cells and be detrimental to the overall health of an organism, robust mechanisms must exist to ensure that genomic integrity is maintained. To test this proposition, we compared the capacity of murine ES cells to repair DNA double-strand breaks with that of differentiated cells. Of the 2 major pathways that repair double-strand breaks, error-prone nonhomologous end joining (NHEJ) predominated in mouse embryonic fibroblasts, whereas the high fidelity homologous recombinational repair (HRR) predominated in ES cells. Microhomology-mediated end joining, an emerging repair pathway, persisted at low levels in all cell types examined. The levels of proteins involved in HRR and microhomology-mediated end joining were highly elevated in ES cells compared with mouse embryonic fibroblasts, whereas those for NHEJ were quite variable, with DNA Ligase IV expression low in ES cells. The half-life of DNA Ligase IV protein was also low in ES cells. Attempts to increase the abundance of DNA Ligase IV protein by overexpression or inhibition of its degradation, and thereby elevate NHEJ in ES cells, were unsuccessful. When ES cells were induced to differentiate, however, the level of DNA Ligase IV protein increased, as did the capacity to repair by NHEJ. The data suggest that preferential use of HRR rather than NHEJ may lend ES cells an additional layer of genomic protection and that the limited levels of DNA Ligase IV may account for the low level of NHEJ activity.

  20. Preclinical study of mouse pluripotent parthenogenetic embryonic stem cell derivatives for the construction of tissue-engineered skin equivalent.

    Science.gov (United States)

    Rao, Yang; Cui, Jihong; Yin, Lu; Liu, Wei; Liu, Wenguang; Sun, Mei; Yan, Xingrong; Wang, Ling; Chen, Fulin

    2016-10-22

    Embryonic stem cell (ESC) derivatives hold great promise for the construction of tissue-engineered skin equivalents (TESE). However, harvesting of ESCs destroys viable embryos and may lead to political and ethical concerns over their application. In the current study, we directed mouse parthenogenetic embryonic stem cells (pESCs) to differentiate into fibroblasts, constructed TESE, and evaluated its function in vivo. The stemness marker expression and the pluripotent differentiation ability of pESCs were tested. After embryoid body (EB) formation and adherence culture, mesenchymal stem cells (MSCs) were enriched and directed to differentiate into fibroblastic lineage. Characteristics of derived fibroblasts were assessed by quantitative real-time PCR and ELISA. Functional ability of the constructed TESE was tested by a mouse skin defects repair model. Mouse pESCs expressed stemness marker and could form teratoma containing three germ layers. MSCs could be enriched from outgrowths of EBs and directed to differentiate into fibroblastic lineage. These cells express a high level of growth factors including FGF, EGF, VEGF, TGF, PDGF, and IGF1, similar to those of ESC-derived fibroblasts and mouse fibroblasts. Seeded into collagen gels, the fibroblasts derived from pESCs could form TESE. Mouse skin defects could be successfully repaired 15 days after transplantation of TESE constructed by fibroblasts derived from pESCs. pESCs could be induced to differentiate into fibroblastic lineage, which could be applied to the construction of TESE and skin defect repair. Particularly, pESC derivatives avoid the limitations of political and ethical concerns, and provide a promising source for regenerative medicine.

  1. Differentiation of mouse embryonic stem cells into cardiomyocytes via the hanging-drop and mass culture methods.

    Science.gov (United States)

    Fuegemann, Christopher J; Samraj, Ajoy K; Walsh, Stuart; Fleischmann, Bernd K; Jovinge, Stefan; Breitbach, Martin

    2010-12-01

    Herein, we describe two protocols for the in vitro differentiation of mouse embryonic stem cells (mESCs) into cardiomyocytes. mESCs are pluripotent and can be differentiated into cells of all three germ layers, including cardiomyocytes. The methods described here facilitate the differentiation of mESCs into the different cardiac subtypes (atrial-, ventricular-, nodal-like cells). The duration of cell culture determines whether preferentially early- or late-developmental stage cardiomyocytes can be obtained preferentially. This approach allows the investigation of cardiomyocyte development and differentiation in vitro, and also allows for the enrichment and isolation of physiologically intact cardiomyocytes for transplantation purposes. © 2010 by John Wiley & Sons, Inc.

  2. Mouse Embryonic Fibroblasts (MEF) Exhibit a Similar but not Identical Phenotype to Bone Marrow Stromal Stem Cells (BMSC)

    DEFF Research Database (Denmark)

    Saeed, Hamid; Taipaleenmäki, Hanna; Aldahmash, Abdullah M

    2012-01-01

    Mouse embryonic fibroblasts have been utilized as a surrogate stem cell model for the postnatal bone marrow-derived stromal stem cells (BMSC) to study mesoderm-type cell differentiation e.g. osteoblasts, adipocytes and chondrocytes. However, no formal characterization of MEF phenotype has been...... by real-time PCR analysis. Compared to BMSC, MEF exhibited a more enhanced differentiation into adipocyte and chondrocyte lineages. Interestingly, both MEF and BMSC formed the same amount of heterotopic bone and bone marrow elements upon in vivo subcutaneous implantation with hydroxyapatite...... and differentiation to osteoblasts, adipocytes and chondrocytes....

  3. Quantitative relationships in delphinid neocortex

    DEFF Research Database (Denmark)

    Mortensen, Heidi S.; Pakkenberg, Bente; Dam, Maria

    2014-01-01

    total number of brain cells in cetaceans, and even fewer have used unbiased counting methods. In this study, using stereological methods, we estimated the total number of cells in the neocortex of the long-finned pilot whale (Globicephala melas) brain. For the first time, we show that a species...

  4. Differentiation of cartilaginous anlage in entire embryonic mouse limbs cultured in a rotating bioreactor.

    Science.gov (United States)

    Duke, P.; Oakley, C.; Montufar-Solis, D.

    The embryonic mammalian limb is sensitive both in vivo and in vitro to changes in gravitational force. Hypergravity of centrifugation and microgravity of space decreased size of elements due to precocious or delayed chondrogenesis respectively. In recapitulating spaceflight experiments, premetatarsals were cultured in suspension in a low stress, low sheer rotating bioreactor, and found to be shorter than those cultured in standard culture dishes, and cartilage development was delayed. This study only measured length of the metatarsals, and did not account for possible changes in width and/or in form of the skeletal elements. Shorter cartilage elements in limbbuds cultured in the bioreactor may be due to the ability of the system to reproduce a more in vivo 3D shape than traditional organ cultures. Tissues subjected to traditional organ cultures become flattened by their own weight, attachment to the filter, and restrictions imposed by nutrient diffusion. The purpose of the current experiment was to determine if entire limb buds could be successfully cultured in the bioreactor, and to compare the effects on 3D shape with that of culturing in a culture dish system. Fore and hind limbs from E11-E13 ICR mouse embryos were placed either in the bioreactor, in Trowell culture, or fixed as controls. Limbbuds were cultured for six days, fixed, and processed either as whole mounts or embedded for histology. Qualitative analysis revealed that the Trowell culture specimens were flattened, while bioreactor culture specimens had a more in vivo-like 3D limb shape. Sections of limbbuds from both types of cultures had excellent cartilage differentiation, with apparently more cell maturation, and hypertrophy in the specimens cultured in the bioreactor. Morphometric quantitation of the cartilaginous elements for comparisons of the two culture systems was complicated due to some limb buds fusing together during culture. This problem was especially noticeable in the younger limbs, and

  5. Differentiation of cartilaginous anlagen in entire embryonic mouse limbs cultured in a rotating bioreactor

    Science.gov (United States)

    Montufar-Solis, D.; Oakley, C. R.; Jefferson, Y.; Duke, P. J.

    2003-10-01

    Mechanisms involved in development of the embryonic limb have remained the same throughout eons of genetic and environmental evolution under Earth gravity (lg). During the spaceflight era it has been of interest to explore the ancient theory that form of the skeleton develops in response to gravity, and that changes in gravitational forces can change the developmental pattern of the limb. This has been shown in vivo and in vitro, allowing the hypergravity of centrifugation and microgravity of space to be used as tools to increase our knowledge of limb development. In recapitulations of spaceflight experiments, premetatarsals were cultured in suspension in a bioreactor, and found to be shorter and less differentiated than those cultured in standard culture dishes. This study only measured length of the metatarsals, and did not account for possible changes due to the skeletal elements having a more in vivo 3D shape while in suspension vs. flattened tissues compressed by their own weight. A culture system with an outcome closer to in vivo and that supports growth of younger limb buds than traditional systems will allow studies of early Hox gene expression, and contribute to the understanding of very early stages of development. The purpose of the current experiment was to determine if entire limb buds could be cultured in the bioreactor, and to compare the growth and differentiation with that of culturing in a culture dish system. Fore and hind limbs from E11-E13 ICR mouse embryos were cultured for six days, either in the bioreactor or in center-well organ culture dishes, fixed, and embedded for histology. E13 specimens grown in culture dishes were flat, while bioreactor culture specimens had a more in vivo-like 3D limb shape. Sections showed excellent cartilage differentiation in both culture systems, with more cell maturation, and hypertrophy in the specimens cultured in the bioreactor. Younger limb buds fused together during culture, so an additional set of El 1

  6. Transient inhibition of cell proliferation does not compromise self-renewal of mouse embryonic stem cells

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Ruoxing [Department of Biological Sciences, The University of Southern Mississippi, 118 College Drive 5018, Hattiesburg, MS 39406 (United States); Guo, Yan-Lin, E-mail: yanlin.guo@usm.edu [Department of Biological Sciences, The University of Southern Mississippi, 118 College Drive 5018, Hattiesburg, MS 39406 (United States)

    2012-10-01

    Embryonic stem cells (ESCs) have unlimited capacity for self-renewal and can differentiate into various cell types when induced. They also have an unusual cell cycle control mechanism driven by constitutively active cyclin dependent kinases (Cdks). In mouse ESCs (mESCs). It is proposed that the rapid cell proliferation could be a necessary part of mechanisms that maintain mESC self-renewal and pluripotency, but this hypothesis is not in line with the finding in human ESCs (hESCs) that the length of the cell cycle is similar to differentiated cells. Therefore, whether rapid cell proliferation is essential for the maintenance of mESC state remains unclear. We provide insight into this uncertainty through chemical intervention of mESC cell cycle. We report here that inhibition of Cdks with olomoucine II can dramatically slow down cell proliferation of mESCs with concurrent down-regulation of cyclin A, B and E, and the activation of the Rb pathway. However, mESCs display can recover upon the removal of olomoucine II and are able to resume normal cell proliferation without losing self-renewal and pluripotency, as demonstrated by the expression of ESC markers, colony formation, embryoid body formation, and induced differentiation. We provide a mechanistic explanation for these observations by demonstrating that Oct4 and Nanog, two major transcription factors that play critical roles in the maintenance of ESC properties, are up-regulated via de novo protein synthesis when the cells are exposed to olomoucine II. Together, our data suggest that short-term inhibition of cell proliferation does not compromise the basic properties of mESCs. -- Highlights: Black-Right-Pointing-Pointer Inhibition of Cdks slows down mESCs proliferation. Black-Right-Pointing-Pointer mESCs display remarkable recovery capacity from short-term cell cycle interruption. Black-Right-Pointing-Pointer Short-term cell cycle interruption does not compromise mESC self-renewal. Black

  7. Generation of Otic Sensory Neurons from Mouse Embryonic Stem Cells in 3D Culture

    Directory of Open Access Journals (Sweden)

    Michael Perny

    2017-12-01

    Full Text Available The peripheral hearing process taking place in the cochlea mainly depends on two distinct sensory cell types: the mechanosensitive hair cells and the spiral ganglion neurons (SGNs. The first respond to the mechanical stimulation exerted by sound pressure waves on their hair bundles by releasing neurotransmitters and thereby activating the latter. Loss of these sensorineural cells is associated with permanent hearing loss. Stem cell-based approaches aiming at cell replacement or in vitro drug testing to identify potential ototoxic, otoprotective, or regenerative compounds have lately gained attention as putative therapeutic strategies for hearing loss. Nevertheless, they rely on efficient and reliable protocols for the in vitro generation of cochlear sensory cells for their implementation. To this end, we have developed a differentiation protocol based on organoid culture systems, which mimics the most important steps of in vivo otic development, robustly guiding mouse embryonic stem cells (mESCs toward otic sensory neurons (OSNs. The stepwise differentiation of mESCs toward ectoderm was initiated using a quick aggregation method in presence of Matrigel in serum-free conditions. Non-neural ectoderm was induced via activation of bone morphogenetic protein (BMP signaling and concomitant inhibition of transforming growth factor beta (TGFβ signaling to prevent mesendoderm induction. Preplacodal and otic placode ectoderm was further induced by inhibition of BMP signaling and addition of fibroblast growth factor 2 (FGF2. Delamination and differentiation of SGNs was initiated by plating of the organoids on a 2D Matrigel-coated substrate. Supplementation with brain-derived neurotrophic factor (BDNF and neurotrophin-3 (NT-3 was used for further maturation until 15 days of in vitro differentiation. A large population of neurons with a clear bipolar morphology and functional excitability was derived from these cultures. Immunostaining and gene expression

  8. Transient inhibition of cell proliferation does not compromise self-renewal of mouse embryonic stem cells

    International Nuclear Information System (INIS)

    Wang, Ruoxing; Guo, Yan-Lin

    2012-01-01

    Embryonic stem cells (ESCs) have unlimited capacity for self-renewal and can differentiate into various cell types when induced. They also have an unusual cell cycle control mechanism driven by constitutively active cyclin dependent kinases (Cdks). In mouse ESCs (mESCs). It is proposed that the rapid cell proliferation could be a necessary part of mechanisms that maintain mESC self-renewal and pluripotency, but this hypothesis is not in line with the finding in human ESCs (hESCs) that the length of the cell cycle is similar to differentiated cells. Therefore, whether rapid cell proliferation is essential for the maintenance of mESC state remains unclear. We provide insight into this uncertainty through chemical intervention of mESC cell cycle. We report here that inhibition of Cdks with olomoucine II can dramatically slow down cell proliferation of mESCs with concurrent down-regulation of cyclin A, B and E, and the activation of the Rb pathway. However, mESCs display can recover upon the removal of olomoucine II and are able to resume normal cell proliferation without losing self-renewal and pluripotency, as demonstrated by the expression of ESC markers, colony formation, embryoid body formation, and induced differentiation. We provide a mechanistic explanation for these observations by demonstrating that Oct4 and Nanog, two major transcription factors that play critical roles in the maintenance of ESC properties, are up-regulated via de novo protein synthesis when the cells are exposed to olomoucine II. Together, our data suggest that short-term inhibition of cell proliferation does not compromise the basic properties of mESCs. -- Highlights: ► Inhibition of Cdks slows down mESCs proliferation. ► mESCs display remarkable recovery capacity from short-term cell cycle interruption. ► Short-term cell cycle interruption does not compromise mESC self-renewal. ► Oct4 and Nanog are up-regulated via de novo synthesis by cell cycle interruption.

  9. A Nestin-cre transgenic mouse is insufficient for recombination in early embryonic neural progenitors

    Directory of Open Access Journals (Sweden)

    Huixuan Liang

    2012-09-01

    Nestin-cre transgenic mice have been widely used to direct recombination to neural stem cells (NSCs and intermediate neural progenitor cells (NPCs. Here we report that a readily utilized, and the only commercially available, Nestin-cre line is insufficient for directing recombination in early embryonic NSCs and NPCs. Analysis of recombination efficiency in multiple cre-dependent reporters and a genetic mosaic line revealed consistent temporal and spatial patterns of recombination in NSCs and NPCs. For comparison we utilized a knock-in Emx1cre line and found robust recombination in NSCs and NPCs in ventricular and subventricular zones of the cerebral cortices as early as embryonic day 12.5. In addition we found that the rate of Nestin-cre driven recombination only reaches sufficiently high levels in NSCs and NPCs during late embryonic and early postnatal periods. These findings are important when commercially available cre lines are considered for directing recombination to embryonic NSCs and NPCs.

  10. Derivation of mouse embryonic stem cell lines from tyrosine hydroxylase reporter mice crossed with a human SNCA transgenic mouse model of Parkinson's disease

    Directory of Open Access Journals (Sweden)

    Margarita Chumarina

    2017-03-01

    Full Text Available Mouse embryonic stem cell (mESC lines were derived by crossing heterozygous transgenic (tg mice expressing green fluorescent protein (GFP under the control of the rat tyrosine hydroxylase (TH promoter, with homozygous alpha-synuclein (aSYN mice expressing human mutant SNCAA53T under the control of the mouse Prion promoter (MoPrP, or wildtype (WT mice. The expression of GFP and human aSYN was validated by immunocytochemistry in midbrain neuron cultures upon differentiation of mESC lines using stromal cell-derived inducing activity. These mESC lines can help to study the impact of human aSYN expression in neurons and oligodendrocytes, and also trace GFP-expressing midbrain neurons.

  11. Influence of high- and low-LET radiation on the cardiac differentiation of mouse embryonic stem cells

    Energy Technology Data Exchange (ETDEWEB)

    Helm, Alexander

    2013-07-19

    The in utero exposure to ionising radiation poses a risk for the radiosensitive developing embryo. Effects of low-LET radiation on different developmental stages of the embryo are relatively well known due to experimental studies and epidemiological data. Data for effects on the very early stage of the embryonic development, particularly the effects of high-LET radiation instead are rather limited. However, unanticipated exposures of the early embryo to ionising radiation may occur through diagnostic or therapeutic applications or through radiation accidents. Additionally, protons and carbon ions are increasingly used in radiotherapy. Thus, a risk estimation of high-LET exposure especially to the early embryo is of a certain importance. To address this topic, pluripotent mouse embryonic stem cells resembling the blastocyst stage were irradiated with high-LET carbon ions or low-LET X-rays and subsequently differentiated to mimic the early embryonic development. The occurrence of spontaneously contracting cardiomyocytes was used as a marker to asses the radiation effects on the differentiation. Among others, cell inactivation, cell death and gene expression were analysed. A delay in the cardiac differentiation after radiation exposure was found. The results point to radiation-induced cell killing as the main effector of the developmental delay. Carbon ions were found to be more effective than X-rays.

  12. Omcg1 is critically required for mitosis in rapidly dividing mouse intestinal progenitors and embryonic stem cells.

    Science.gov (United States)

    Léguillier, Teddy; Vandormael-Pournin, Sandrine; Artus, Jérôme; Houlard, Martin; Picard, Christel; Bernex, Florence; Robine, Sylvie; Cohen-Tannoudji, Michel

    2012-07-15

    Recent studies have shown that factors involved in transcription-coupled mRNA processing are important for the maintenance of genome integrity. How these processes are linked and regulated in vivo remains largely unknown. In this study, we addressed in the mouse model the function of Omcg1, which has been shown to participate in co-transcriptional processes, including splicing and transcription-coupled repair. Using inducible mouse models, we found that Omcg1 is most critically required in intestinal progenitors. In absence of OMCG1, proliferating intestinal epithelial cells underwent abnormal mitosis followed by apoptotic cell death. As a consequence, the crypt proliferative compartment of the small intestine was quickly and totally abrogated leading to the rapid death of the mice. Lack of OMCG1 in embryonic stem cells led to a similar cellular phenotype, with multiple mitotic defects and rapid cell death. We showed that mutant intestinal progenitors and embryonic stem cells exhibited a reduced cell cycle arrest following irradiation, suggesting that mitotic defects may be consecutive to M phase entry with unrepaired DNA damages. These findings unravel a crucial role for pre-mRNA processing in the homeostasis of the small intestine and point to a major role of OMCG1 in the maintenance of genome integrity.

  13. Omcg1 is critically required for mitosis in rapidly dividing mouse intestinal progenitors and embryonic stem cells

    Directory of Open Access Journals (Sweden)

    Teddy Léguillier

    2012-05-01

    Recent studies have shown that factors involved in transcription-coupled mRNA processing are important for the maintenance of genome integrity. How these processes are linked and regulated in vivo remains largely unknown. In this study, we addressed in the mouse model the function of Omcg1, which has been shown to participate in co-transcriptional processes, including splicing and transcription-coupled repair. Using inducible mouse models, we found that Omcg1 is most critically required in intestinal progenitors. In absence of OMCG1, proliferating intestinal epithelial cells underwent abnormal mitosis followed by apoptotic cell death. As a consequence, the crypt proliferative compartment of the small intestine was quickly and totally abrogated leading to the rapid death of the mice. Lack of OMCG1 in embryonic stem cells led to a similar cellular phenotype, with multiple mitotic defects and rapid cell death. We showed that mutant intestinal progenitors and embryonic stem cells exhibited a reduced cell cycle arrest following irradiation, suggesting that mitotic defects may be consecutive to M phase entry with unrepaired DNA damages. These findings unravel a crucial role for pre-mRNA processing in the homeostasis of the small intestine and point to a major role of OMCG1 in the maintenance of genome integrity.

  14. Extract of mouse embryonic stem cells induces the expression of pluripotency genes in human adipose tissue-derived stem cells.

    Science.gov (United States)

    Salehi, Paria Motamen; Foroutan, Tahereh; Javeri, Arash; Taha, Masoumeh Fakhr

    2017-11-01

    In some previous studies, the extract of embryonic carcinoma cells (ECCs) and embryonic stem cells (ESCs) have been used to reprogram somatic cells to more dedifferentiated state. The aim of this study was to investigate the effect of mouse ESCs extract on the expression of some pluripotency markers in human adipose tissue-derived stem cells (ADSCs). Human ADSCs were isolated from subcutaneous abdominal adipose tissue and characterized by flow cytometric analysis for the expression of some mesenchymal stem cell markers and adipogenic and osteogenic differentiation. Frequent freeze-thaw technique was used to prepare cytoplasmic extract of ESCs. Plasma membranes of the ADSCs were reversibly permeabilized by streptolysin-O (SLO). Then the permeabilized ADSCs were incubated with the ESC extract and cultured in resealing medium. After reprogramming, the expression of some pluripotency genes was evaluated by RT-PCR and quantitative real-time PCR (qPCR) analyses. Third-passaged ADSCs showed a fibroblast-like morphology and expressed mesenchymal stem cell markers. They also showed adipogenic and osteogenic differentiation potential. QPCR analysis revealed a significant upregulation in the expression of some pluripotency genes including OCT4 , SOX2 , NANOG , REX1 and ESG1 in the reprogrammed ADSCs compared to the control group. These findings showed that mouse ESC extract can be used to induce reprogramming of human ADSCs. In fact, this method is applicable for reprogramming of human adult stem cells to a more pluripotent sate and may have a potential in regenerative medicine.

  15. Activation of GSK3β by Sirt2 is required for early lineage commitment of mouse embryonic stem cell.

    Directory of Open Access Journals (Sweden)

    Xiaoxing Si

    Full Text Available Sirt2, a member of the NAD(+-dependent protein deacetylase family, is increasingly recognized as a critical regulator of the cell cycle, cellular necrosis and cytoskeleton organization. However, its role in embryonic stem cells (ESCs remains unclear. Here we demonstrate that Sirt2 is up-regulated during RA (retinoic acid-induced and embryoid body (EB differentiation of mouse ESCs. Using lentivirus-mediated shRNA methods, we found that knockdown of Sirt2 compromises the differentiation of mouse ESCs into ectoderm while promoting mesoderm and endoderm differentiation. Knockdown of Sirt2 expression also leads to the activation of GSK3β through decreased phosphorylation of the serine at position 9 (Ser9 but not tyrosine at position 216 (Tyr216. Moreover, the constitutive activation of GSK3β during EB differentiation mimics the effect of Sirt2 knockdown, while down-regulation of GSK3β rescues the effect of Sirt2 knockdown on differentiation. In contrast to the effect on lineage differentiation, Sirt2 knockdown and GSK3β up-regulation do not change the self-renewal state of mouse ESCs. Overall, our report reveals a new function for Sirt2 in regulating the proper lineage commitment of mouse ESCs.

  16. Merkel Cell Polyomavirus Small T Antigen Induces Cancer and Embryonic Merkel Cell Proliferation in a Transgenic Mouse Model.

    Science.gov (United States)

    Shuda, Masahiro; Guastafierro, Anna; Geng, Xuehui; Shuda, Yoko; Ostrowski, Stephen M; Lukianov, Stefan; Jenkins, Frank J; Honda, Kord; Maricich, Stephen M; Moore, Patrick S; Chang, Yuan

    2015-01-01

    Merkel cell polyomavirus (MCV) causes the majority of human Merkel cell carcinomas (MCC) and encodes a small T (sT) antigen that transforms immortalized rodent fibroblasts in vitro. To develop a mouse model for MCV sT-induced carcinogenesis, we generated transgenic mice with a flox-stop-flox MCV sT sequence homologously recombined at the ROSA locus (ROSAsT), allowing Cre-mediated, conditional MCV sT expression. Standard tamoxifen (TMX) administration to adult UbcCreERT2; ROSAsT mice, in which Cre is ubiquitously expressed, resulted in MCV sT expression in multiple organs that was uniformly lethal within 5 days. Conversely, most adult UbcCreERT2; ROSAsT mice survived low-dose tamoxifen administration but developed ear lobe dermal hyperkeratosis and hypergranulosis. Simultaneous MCV sT expression and conditional homozygous p53 deletion generated multi-focal, poorly-differentiated, highly anaplastic tumors in the spleens and livers of mice after 60 days of TMX treatment. Mouse embryonic fibroblasts from these mice induced to express MCV sT exhibited anchorage-independent cell growth. To examine Merkel cell pathology, MCV sT expression was also induced during mid-embryogenesis in Merkel cells of Atoh1CreERT2/+; ROSAsT mice, which lead to significantly increased Merkel cell numbers in touch domes at late embryonic ages that normalized postnatally. Tamoxifen administration to adult Atoh1CreERT2/+; ROSAsT and Atoh1CreERT2/+; ROSAsT; p53flox/flox mice had no effects on Merkel cell numbers and did not induce tumor formation. Taken together, these results show that MCV sT stimulates progenitor Merkel cell proliferation in embryonic mice and is a bona fide viral oncoprotein that induces full cancer cell transformation in the p53-null setting.

  17. Gene expression response to EWS–FLI1 in mouse embryonic cartilage

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    Miwa Tanaka

    2014-12-01

    Full Text Available Ewing's sarcoma is a rare bone tumor that affects children and adolescents. We have recently succeeded to induce Ewing's sarcoma-like small round cell tumor in mice by expression of EWS–ETS fusion genes in murine embryonic osteochondrogenic progenitors. The Ewing's sarcoma precursors are enriched in embryonic superficial zone (eSZ cells of long bone. To get insights into the mechanisms of Ewing's sarcoma development, gene expression profiles between EWS–FLI1-sensitive eSZ cells and EWS–FLI1-resistant embryonic growth plate (eGP cells were compared using DNA microarrays. Gene expression of eSZ and eGP cells (total, 30 samples was evaluated with or without EWS–FLI1 expression 0, 8 or 48 h after gene transduction. Our data provide useful information for gene expression responses to fusion oncogenes in human sarcoma.

  18. Characterization and comparison of osteoblasts derived from mouse embryonic stem cells and induced pluripotent stem cells

    NARCIS (Netherlands)

    Ma, Ming San; Kannan, Vishnu; de Vries, Anneriek E; Czepiel, Marcin; Wesseling, Evelyn; Balasubramaniyan, Veerakumar; Kuijer, Roelof; Vissink, Arjan; Copray, Sjef; Raghoebar, Gerry

    New developments in stem cell biology offer alternatives for the reconstruction of critical-sized bone defects. One of these developments is the use of induced pluripotent stem (iPS) cells. These stem cells are similar to embryonic stem (ES) cells, but can be generated from adult somatic cells and

  19. In vitro labelling of mouse embryonic stem cells with SPIO nanoparticles

    Czech Academy of Sciences Publication Activity Database

    Krejčí, Jana; Pacherník, J.; Hampl, Aleš; Dvořák, Petr

    2008-01-01

    Roč. 27, č. 3 (2008), s. 164-173 ISSN 0231-5882 Grant - others:GA ČR(CZ) GA301/08/0717 Institutional research plan: CEZ:AV0Z50040507; CEZ:AV0Z50040702 Keywords : embryonic stem cells * differentiation * magnetic labelling Subject RIV: BO - Biophysics Impact factor: 0.697, year: 2008

  20. Evaluation of a Mouse Embryonic Stem Cell Adherent Cell Differentiation and Cytotoxicity (ACDC) assay (SOT)

    Science.gov (United States)

    The Embryonic Stem Cell Test (EST) has been used to evaluate the effects of xenobiotics using three endpoints, stem cell differentiation, stem cell viability and 3T3-cell viability. Our research goal is to establish amodel system that would evaluate chemical effects using a singl...

  1. Cdk2 Inhibition Prolongs G1 Phase Progression in Mouse Embryonic Stem Cells

    Czech Academy of Sciences Publication Activity Database

    Koledová, Z.; Rašková-Kafková, L.; Calábková, L.; Kryštof, Vladimír; Doležel, P.; Divoký, V.

    2010-01-01

    Roč. 19, č. 2 (2010), s. 181-193 ISSN 1547-3287 R&D Projects: GA ČR GA301/08/1649 Institutional research plan: CEZ:AV0Z50380511 Keywords : embryonic stem cells * cell cycle * G1 phase Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 4.791, year: 2010

  2. Novel insights into embryonic stem cell self-renewal revealed through comparative human and mouse systems biology networks.

    Science.gov (United States)

    Dowell, Karen G; Simons, Allen K; Bai, Hao; Kell, Braden; Wang, Zack Z; Yun, Kyuson; Hibbs, Matthew A

    2014-05-01

    Embryonic stem cells (ESCs), characterized by their ability to both self-renew and differentiate into multiple cell lineages, are a powerful model for biomedical research and developmental biology. Human and mouse ESCs share many features, yet have distinctive aspects, including fundamental differences in the signaling pathways and cell cycle controls that support self-renewal. Here, we explore the molecular basis of human ESC self-renewal using Bayesian network machine learning to integrate cell-type-specific, high-throughput data for gene function discovery. We integrated high-throughput ESC data from 83 human studies (~1.8 million data points collected under 1,100 conditions) and 62 mouse studies (~2.4 million data points collected under 1,085 conditions) into separate human and mouse predictive networks focused on ESC self-renewal to analyze shared and distinct functional relationships among protein-coding gene orthologs. Computational evaluations show that these networks are highly accurate, literature validation confirms their biological relevance, and reverse transcriptase polymerase chain reaction (RT-PCR) validation supports our predictions. Our results reflect the importance of key regulatory genes known to be strongly associated with self-renewal and pluripotency in both species (e.g., POU5F1, SOX2, and NANOG), identify metabolic differences between species (e.g., threonine metabolism), clarify differences between human and mouse ESC developmental signaling pathways (e.g., leukemia inhibitory factor (LIF)-activated JAK/STAT in mouse; NODAL/ACTIVIN-A-activated fibroblast growth factor in human), and reveal many novel genes and pathways predicted to be functionally associated with self-renewal in each species. These interactive networks are available online at www.StemSight.org for stem cell researchers to develop new hypotheses, discover potential mechanisms involving sparsely annotated genes, and prioritize genes of interest for experimental validation

  3. Interspecies chimera between primate embryonic stem cells and mouse embryos: monkey ESCs engraft into mouse embryos, but not post-implantation fetuses.

    Science.gov (United States)

    Simerly, Calvin; McFarland, Dave; Castro, Carlos; Lin, Chih-Cheng; Redinger, Carrie; Jacoby, Ethan; Mich-Basso, Jocelyn; Orwig, Kyle; Mills, Parker; Ahrens, Eric; Navara, Chris; Schatten, Gerald

    2011-07-01

    Unequivocal evidence for pluripotency in which embryonic stem cells contribute to chimeric offspring has yet to be demonstrated in human or nonhuman primates (NHPs). Here, rhesus and baboons ESCs were investigated in interspecific mouse chimera generated by aggregation or blastocyst injection. Aggregation chimera produced mouse blastocysts with GFP-nhpESCs at the inner cell mass (ICM), and embryo transfers (ETs) generated dimly-fluorescencing abnormal fetuses. Direct injection of GFP-nhpESCs into blastocysts produced normal non-GFP-fluorescencing fetuses. Injected chimera showed >70% loss of GFP-nhpESCs after 21 h culture. Outgrowths of all chimeric blastocysts established distinct but separate mouse- and NHP-ESC colonies. Extensive endogenous autofluorescence compromised anti-GFP detection and PCR analysis did not detect nhpESCs in fetuses. NhpESCs localize to the ICM in chimera and generate pregnancies. Because primate ESCs do not engraft post-implantation, and also because endogenous autofluorescence results in misleading positive signals, interspecific chimera assays for pluripotency with primate stem cells is unreliable with the currently available ESCs. Testing primate ESCs reprogrammed into even more naïve states in these inter-specific chimera assays will be an important future endeavor. Copyright © 2011 Elsevier B.V. All rights reserved.

  4. Proliferation assay of mouse embryonic stem (ES) cells exposed to atmospheric-pressure plasmas at room temperature

    International Nuclear Information System (INIS)

    Miura, Taichi; Hirano, Kazumi; Ogura, Chika; Ikeguchi, Masamichi; Seki, Atsushi; Nishihara, Shoko; Ando, Ayumi; Kanazawa, Tatsuya; Hamaguchi, Satoshi

    2014-01-01

    Proliferation assays of mouse embryonic stem (ES) cells have been performed with cell culture media exposed to atmospheric-pressure plasmas (APPs), which generate reactive species in the media at room temperature. It is found that serum in cell culture media functions as a scavenger of highly reactive species and tends to protect cells in the media against cellular damage. On the other hand, if serum is not present in a cell culture medium when it is exposed to APP, the medium becomes cytotoxic and cannot be detoxified by serum added afterwards. Plasma-induced cytotoxic media hinder proliferation of mouse ES cells and may even cause cell death. It is also shown by nuclear magnetic resonance spectroscopy that organic compounds in cell culture media are in general not significantly modified by plasma exposure. These results indicate that if there is no serum in media when they are exposed to APPs, highly reactive species (such as OH radicals) generated in the media by the APP exposure are immediately converted to less reactive species (such as H 2 O 2 ), which can no longer readily react with serum that is added to the medium after plasma exposure. This study has clearly shown that it is these less reactive species, rather than highly reactive species, that make the medium cytotoxic to mouse ES cells. (paper)

  5. The miR-17-92 cluster regulates FOG-2 expression and inhibits proliferation of mouse embryonic cardiomyocytes

    Directory of Open Access Journals (Sweden)

    Rui Xiang

    2012-02-01

    Full Text Available MicroRNAs (miRNAs have gradually been recognized as regulators of embryonic development; however, relatively few miRNAs have been identified that regulate cardiac development. A series of recent papers have established an essential role for the miRNA-17-92 (miR-17-92 cluster of miRNAs in the development of the heart. Previous research has shown that the Friend of Gata-2 (FOG-2 is critical for cardiac development. To investigate the possibility that the miR-17-92 cluster regulates FOG-2 expression and inhibits proliferation in mouse embryonic cardiomyocytes we initially used bioinformatics to analyze 3’ untranslated regions (3’UTR of FOG-2 to predict the potential of miR-17-92 to target it. We used luciferase assays to demonstrate that miR-17-5p and miR-20a of miR-17-92 interact with the predicted target sites in the 3’UTR of FOG-2. Furthermore, RT-PCR and Western blot were used to demonstrate the post-transcriptional regulation of FOG-2 by miR-17-92 in embryonic cardiomyocytes from E12.5-day pregnant C57BL/6J mice. Finally, EdU cell assays together with the FOG-2 rescue strategy were employed to evaluate the effect of proliferation on embryonic cardiomyocytes. We first found that the miR-17-5p and miR-20a of miR-17-92 directly target the 3’UTR of FOG-2 and post-transcriptionally repress the expression of FOG-2. Moreover, our findings demonstrated that over-expression of miR-17-92 may inhibit cell proliferation via post-transcriptional repression of FOG-2 in embryonic cardiomyocytes. These results indicate that the miR-17-92 cluster regulates the expression of FOG-2 protein and suggest that the miR-17-92 cluster might play an important role in heart development.

  6. The miR-17-92 cluster regulates FOG-2 expression and inhibits proliferation of mouse embryonic cardiomyocytes.

    Science.gov (United States)

    Xiang, Rui; Lei, Han; Chen, Mianzhi; Li, Qinwei; Sun, Huan; Ai, Jianzhong; Chen, Tielin; Wang, Honglian; Fang, Yin; Zhou, Qin

    2012-02-01

    MicroRNAs (miRNAs) have gradually been recognized as regulators of embryonic development; however, relatively few miRNAs have been identified that regulate cardiac development. A series of recent papers have established an essential role for the miRNA-17-92 (miR-17-92) cluster of miRNAs in the development of the heart. Previous research has shown that the Friend of Gata-2 (FOG-2) is critical for cardiac development. To investigate the possibility that the miR-17-92 cluster regulates FOG-2 expression and inhibits proliferation in mouse embryonic cardiomyocytes we initially used bioinformatics to analyze 3' untranslated regions (3'UTR) of FOG-2 to predict the potential of miR-17-92 to target it. We used luciferase assays to demonstrate that miR-17-5p and miR-20a of miR-17-92 interact with the predicted target sites in the 3'UTR of FOG-2. Furthermore, RT-PCR and Western blot were used to demonstrate the post-transcriptional regulation of FOG-2 by miR-17-92 in embryonic cardiomyocytes from E12.5-day pregnant C57BL/6J mice. Finally, EdU cell assays together with the FOG-2 rescue strategy were employed to evaluate the effect of proliferation on embryonic cardiomyocytes. We first found that the miR-17-5p and miR-20a of miR-17-92 directly target the 3'UTR of FOG-2 and post-transcriptionally repress the expression of FOG-2. Moreover, our findings demonstrated that over-expression of miR-17-92 may inhibit cell proliferation via post-transcriptional repression of FOG-2 in embryonic cardiomyocytes. These results indicate that the miR-17-92 cluster regulates the expression of FOG-2 protein and suggest that the miR-17-92 cluster might play an important role in heart development.

  7. Investigation of a redox-sensitive predictive model of mouse embryonic stem cells differentiation using quantitative nuclease protection assays and glutathione redox status

    Science.gov (United States)

    Investigation of a redox-sensitive predictive model of mouse embryonic stem cell differentiation via quantitative nuclease protection assays and glutathione redox status Chandler KJ,Hansen JM, Knudsen T,and Hunter ES 1. U.S. Environmental Protection Agency, Research Triangl...

  8. Circadian clock components in the rat neocortex

    DEFF Research Database (Denmark)

    Rath, Martin Fredensborg; Rohde, Kristian; Fahrenkrug, Jan

    2013-01-01

    in the rat neocortex. Among these, Per1, Per2, Per3, Cry1, Bmal1, Nr1d1 and Dbp were found to exhibit daily rhythms. The amplitude of circadian oscillation in neocortical clock gene expression was damped and the peak delayed as compared with the SCN. Lesions of the SCN revealed that rhythmic clock gene...... expression in the neocortex is dependent on the SCN. In situ hybridization and immunohistochemistry showed that products of the canonical clock gene Per2 are located in perikarya throughout all areas of the neocortex. These findings show that local circadian oscillators driven by the SCN reside within...... neurons of the neocortex....

  9. A short G1 phase imposes constitutive replication stress and fork remodelling in mouse embryonic stem cells

    DEFF Research Database (Denmark)

    Ahuja, Akshay K.; Jodkowska, Karolina; Teloni, Federico

    2016-01-01

    Embryonic stem cells (ESCs) represent a transient biological state, where pluripotency is coupled with fast proliferation. ESCs display a constitutively active DNA damage response (DDR), but its molecular determinants have remained elusive. Here we show in cultured ESCs and mouse embryos that H2AX...... these marks of replication stress do not impair the mitotic process and are rapidly lost at differentiation onset. Delaying the G1/S transition in ESCs allows formation of 53BP1 nuclear bodies and suppresses ssDNA accumulation, fork slowing and reversal in the following S-phase. Genetic inactivation of fork...... slowing and reversal leads to chromosomal breakage in unperturbed ESCs. We propose that rapid cell cycle progression makes ESCs dependent on effective replication-coupled mechanisms to protect genome integrity....

  10. Transcriptional regulatory program in wild-type and retinoblastoma gene-deficient mouse embryonic fibroblasts during adipocyte differentiation

    DEFF Research Database (Denmark)

    Hakim-Weber, Robab; Krogsdam, Anne-M; Jørgensen, Claus

    2011-01-01

    Although many molecular regulators of adipogenesis have been identified a comprehensive catalogue of components is still missing. Recent studies showed that the retinoblastoma protein (pRb) was expressed in the cell cycle and late cellular differentiation phase during adipogenesis. To investigate...... this dual role of pRb in the early and late stages of adipogenesis we used microarrays to perform a comprehensive systems-level analysis of the common transcriptional program of the classic 3T3-L1 preadipocyte cell line, wild-type mouse embryonic fibroblasts (MEFs), and retinoblastoma gene-deficient MEFs...... of experimental data and computational analyses pinpointed a feedback-loop between Pparg and Foxo1.To analyze the effects of the retinoblastoma protein at the transcriptional level we chose a perturbated system (Rb-/- MEFs) for comparison to the transcriptional program of wild-type MEFs. Gene ontology analysis...

  11. The Role of Controlled Surface Topography and Chemistry on Mouse Embryonic Stem Cell Attachment, Growth and Self-Renewal.

    Science.gov (United States)

    Macgregor, Melanie; Williams, Rachel; Downes, Joni; Bachhuka, Akash; Vasilev, Krasimir

    2017-09-14

    The success of stem cell therapies relies heavily on our ability to control their fate in vitro during expansion to ensure an appropriate supply. The biophysical properties of the cell culture environment have been recognised as a potent stimuli influencing cellular behaviour. In this work we used advanced plasma-based techniques to generate model culture substrates with controlled nanotopographical features of 16 nm, 38 nm and 68 nm in magnitude, and three differently tailored surface chemical functionalities. The effect of these two surface properties on the adhesion, spreading, and self-renewal of mouse embryonic stem cells (mESCs) were assessed. The results demonstrated that physical and chemical cues influenced the behaviour of these stem cells in in vitro culture in different ways. The size of the nanotopographical features impacted on the cell adhesion, spreading and proliferation, while the chemistry influenced the cell self-renewal and differentiation.

  12. Odorant responsiveness of embryonic mouse olfactory sensory neurons expressing the odorant receptors S1 or MOR23.

    Science.gov (United States)

    Lam, Rebecca S; Mombaerts, Peter

    2013-07-01

    The mammalian olfactory system has developed some functionality by the time of birth. There is behavioral and limited electrophysiological evidence for prenatal olfaction in various mammalian species. However, there have been no reports, in any mammalian species, of recordings from prenatal olfactory sensory neurons (OSNs) that express a given odorant receptor (OR) gene. Here we have performed patch-clamp recordings from mouse OSNs that express the OR gene S1 or MOR23, using the odorous ligands 2-phenylethyl alcohol or lyral, respectively. We found that, out of a combined total of 20 OSNs from embryos of these two strains at embryonic day (E)16.5 or later, all responded to a cognate odorous ligand. By contrast, none of six OSNs responded to the ligand at E14.5 or E15.5. The kinetics of the odorant-evoked electrophysiological responses of prenatal OSNs are similar to those of postnatal OSNs. The S1 and MOR23 glomeruli in the olfactory bulb are formed postnatally, but the axon terminals of OSNs expressing these OR genes may be synaptically active in the olfactory bulb at embryonic stages. The upper limit of the acquisition of odorant responsiveness for S1 and MOR23 OSNs at E16.5 is consistent with the developmental expression patterns of components of the olfactory signaling pathway. © 2013 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  13. Establishment of new murine embryonic stem cell lines for the generation of mouse models of human genetic diseases

    Directory of Open Access Journals (Sweden)

    M.A. Sukoyan

    2002-05-01

    Full Text Available Embryonic stem cells are totipotent cells derived from the inner cell mass of blastocysts. Recently, the development of appropriate culture conditions for the differentiation of these cells into specific cell types has permitted their use as potential therapeutic agents for several diseases. In addition, manipulation of their genome in vitro allows the creation of animal models of human genetic diseases and for the study of gene function in vivo. We report the establishment of new lines of murine embryonic stem cells from preimplantation stage embryos of 129/Sv mice. Most of these cells had a normal karyotype and an XY sex chromosome composition. The pluripotent properties of the cell lines obtained were analyzed on the basis of their alkaline phosphatase activity and their capacity to form complex embryoid bodies with rhythmically contracting cardiomyocytes. Two lines, USP-1 and USP-3, with the best in vitro characteristics of pluripotency were used in chimera-generating experiments. The capacity to contribute to the germ line was demonstrated by the USP-1 cell line. This cell line is currently being used to generate mouse models of human diseases.

  14. Defined culture medium for stem cell differentiation: applicability of serum-free conditions in the mouse embryonic stem cell test.

    Science.gov (United States)

    Riebeling, Christian; Schlechter, Katharina; Buesen, Roland; Spielmann, Horst; Luch, Andreas; Seiler, Andrea

    2011-06-01

    The embryonic stem cell test (EST) is a validated method to assess the developmental toxicity potency of chemicals. It was developed to reduce animal use and allow faster testing for hazard assessment. The cells used in this method are maintained and differentiated in media containing foetal calf serum. This animal product is of considerable variation in quality, and individual batches require extensive testing for their applicability in the EST. Moreover, its production involves a large number of foetuses and possible animal suffering. We demonstrate the serum-free medium and feeder cell-free maintenance of the mouse embryonic stem cell line D3 and investigate the use of specific growth factors for induction of cardiac differentiation. Using a combination of bone morphogenetic protein-2, bone morphogenetic protein-4, activin A and ascorbic acid, embryoid bodies efficiently differentiated into contracting myocardium. Additionally, examining levels of intracellular marker proteins by flow cytometry not only confirmed differentiation into cardiomyocytes, but demonstrated significant differentiation into neuronal cells in the same time frame. Thus, this approach might allow for simultaneous detection of developmental effects on both early mesodermal and neuroectodermal differentiation. The serum-free conditions for maintenance and differentiation of D3 cells described here enhance the transferability and standardisation and hence the performance of the EST. Copyright © 2011 Elsevier Ltd. All rights reserved.

  15. Growth and morphogenesis of embryonic mouse organs on non-coated and extracellular matrix-coated Biopore membrane

    Science.gov (United States)

    Hardman, P.; Klement, B. J.; Spooner, B. S.

    1993-01-01

    Embryonic mouse salivary glands, pancreata, and kidneys were isolated from embryos of appropriate gestational age by microdissection, and were cultured on Biopore membrane either non-coated or coated with type I collagen or Matrigel. As expected, use of Biopore membrane allowed high quality photomicroscopy of the living organs. In all organs extensive mesenchymal spreading was observed in the presence of type I collagen or Matrigel. However, differences were noted in the effects of extracellular matrix (ECM) coatings on epithelial growth and morphogenesis: salivary glands were minimally affected, pancreas morphogenesis was adversely affected, and kidney growth and branching apparently was enhanced. It is suggested that these differences in behaviour reflect differences in the strength of interactions between the mesenchymal cells and their surrounding endogenous matrix, compared to the exogenous ECM macromolecules. This method will be useful for culture of these and other embryonic organs. In particular, culture of kidney rudiments on ECM-coated Biopore offers a great improvement over previously used methods which do not allow morphogenesis to be followed in vitro.

  16. Disruption of the Sec24d gene results in early embryonic lethality in the mouse.

    Directory of Open Access Journals (Sweden)

    Andrea C Baines

    Full Text Available Transport of newly synthesized proteins from the endoplasmic reticulum (ER to the Golgi is mediated by the coat protein complex COPII. The inner coat of COPII is assembled from heterodimers of SEC23 and SEC24. Though mice with mutations in one of the four Sec24 paralogs, Sec24b, exhibit a neural tube closure defect, deficiency in humans or mice has not yet been described for any of the other Sec24 paralogs. We now report characterization of mice with targeted disruption of Sec24d. Early embryonic lethality is observed in mice completely deficient in SEC24D, while a hypomorphic Sec24d allele permits survival to mid-embryogenesis. Mice haploinsufficient for Sec24d exhibit no phenotypic abnormality. A BAC transgene containing Sec24d rescues the embryonic lethality observed in Sec24d-null mice. These results demonstrate an absolute requirement for SEC24D expression in early mammalian development that is not compensated by the other three Sec24 paralogs. The early embryonic lethality resulting from loss of SEC24D in mice contrasts with the previously reported mild skeletal phenotype of SEC24D deficiency in zebrafish and restricted neural tube phenotype of SEC24B deficiency in mice. Taken together, these observations suggest that the multiple Sec24 paralogs have developed distinct functions over the course of vertebrate evolution.

  17. Comparison of frailty of primary neurons, embryonic, and aging mouse cortical layers.

    Science.gov (United States)

    Fugistier, Patrick; Vallet, Philippe G; Leuba, Geneviève; Piotton, Françoise; Marin, Pascale; Bouras, Constantin; Savioz, Armand

    2014-02-01

    Superficial layers I to III of the human cerebral cortex are more vulnerable toward Aβ peptides than deep layers V to VI in aging. Three models of layers were used to investigate this pattern of frailty. First, primary neurons from E14 and E17 embryonic murine cortices, corresponding respectively to future deep and superficial layers, were treated either with Aβ(1-42), okadaic acid, or kainic acid. Second, whole E14 and E17 embryonic cortices, and third, in vitro separated deep and superficial layers of young and old C57BL/6J mice, were treated identically. We observed that E14 and E17 neurons in culture were prone to death after the Aβ and particularly the kainic acid treatment. This was also the case for the superficial layers of the aged cortex, but not for the embryonic, the young cortex, and the deep layers of the aged cortex. Thus, the aged superficial layers appeared to be preferentially vulnerable against Aβ and kainic acid. This pattern of vulnerability corresponds to enhanced accumulation of senile plaques in the superficial cortical layers with aging and Alzheimer's disease. Copyright © 2014 Elsevier Inc. All rights reserved.

  18. Generation of tooth-periodontium complex structures using high-odontogenic potential dental epithelium derived from mouse embryonic stem cells.

    Science.gov (United States)

    Zhang, Yancong; Li, Yongliang; Shi, Ruirui; Zhang, Siqi; Liu, Hao; Zheng, Yunfei; Li, Yan; Cai, Jinglei; Pei, Duanqing; Wei, Shicheng

    2017-06-08

    A number of studies have shown that tooth-like structures can be regenerated using induced pluripotent stem cells and mouse embryonic stem (mES) cells. However, few studies have reported the regeneration of tooth-periodontium complex structures, which are more suitable for clinical tooth transplantation. We established an optimized approach to induce high-odontogenic potential dental epithelium derived from mES cells by temporally controlling bone morphogenic protein 4 (BMP4) function and regenerated tooth-periodontium complex structures in vivo. First, immunofluorescence and quantitative reverse transcription-polymerase chain reaction were used to identify the watershed of skin and the oral ectoderm. LDN193189 was then used to inhibit the BMP4 receptor around the watershed, followed by the addition of exogenous BMP4 to promote BMP4 function. The generated dental epithelium was confirmed by western blot analysis and immunofluorescence. The generated epithelium was ultimately combined with embryonic day 14.5 mouse mesenchyme and transplanted into the renal capsules of nude mice. After 4 weeks, the tooth-periodontium complex structure was examined by micro-computed tomography (CT) and hematoxylin and eosin (H&E) staining. Our study found that the turning point of oral ectoderm differentiation occurred around day 3 after the embryoid body was transferred to a common culture plate. Ameloblastin-positive dental epithelial cells were detected following the temporal regulation of BMP4. Tooth-periodontium complex structures, which included teeth, a periodontal membrane, and alveolar bone, were formed when this epithelium was combined with mouse dental mesenchyme and transplanted into the renal capsules of nude mice. Micro-CT and H&E staining revealed that the generated tooth-periodontium complex structures shared a similar histological structure with normal mouse teeth. An optimized induction method was established to promote the differentiation of mES cells into dental

  19. Chromosomal instability in mouse embryonic fibroblasts null for the transcriptional co-repressor Ski

    OpenAIRE

    Marcelain, Katherine; Armisen, Ricardo; Aguirre, Adam; Ueki, Nobuhide; Toro, Jessica; Colmenares, Clemencia; Hayman, Michael J

    2012-01-01

    Ski is a transcriptional regulator that has been considered an oncoprotein, given its ability to induce oncogenic transformation in avian model systems. However, studies in mouse and in some human tumor cells have also indicated a tumor suppressor activity for this protein. We found that Ski−/− mouse embryo fibroblasts exhibit high levels of genome instability, namely aneuploidy, consistent with a tumor suppressor function for Ski. Time-lapse microscopy revealed lagging chromosomes and chroma...

  20. Cyclic mechanical strain maintains Nanog expression through PI3K/Akt signaling in mouse embryonic stem cells

    Energy Technology Data Exchange (ETDEWEB)

    Horiuchi, Rie [Division of Regenerative Medical Engineering, Center for Disease Biology and Integrative Medicine, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-0033 (Japan); Akimoto, Takayuki, E-mail: akimoto@m.u-tokyo.ac.jp [Division of Regenerative Medical Engineering, Center for Disease Biology and Integrative Medicine, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-0033 (Japan); Institute for Biomedical Engineering, Consolidated Research Institute for Advanced Science and Medical Care, Waseda University, 513 Waseda-tsurumaki, Shinjuku, Tokyo 162-0041 (Japan); Hong, Zhang [Institute for Biomedical Engineering, Consolidated Research Institute for Advanced Science and Medical Care, Waseda University, 513 Waseda-tsurumaki, Shinjuku, Tokyo 162-0041 (Japan); Ushida, Takashi [Division of Regenerative Medical Engineering, Center for Disease Biology and Integrative Medicine, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-0033 (Japan)

    2012-08-15

    Mechanical strain has been reported to affect the proliferation/differentiation of many cell types; however, the effects of mechanotransduction on self-renewal as well as pluripotency of embryonic stem (ES) cells remains unknown. To investigate the effects of mechanical strain on mouse ES cell fate, we examined the expression of Nanog, which is an essential regulator of self-renewal and pluripotency as well as Nanog-associated intracellular signaling during uniaxial cyclic mechanical strain. The mouse ES cell line, CCE was plated onto elastic membranes, and we applied 10% strain at 0.17 Hz. The expression of Nanog was reduced during ES cell differentiation in response to the withdrawal of leukemia inhibitory factor (LIF); however, two days of cyclic mechanical strain attenuated this reduction of Nanog expression. On the other hand, the cyclic mechanical strain promoted PI3K-Akt signaling, which is reported as an upstream of Nanog transcription. The cyclic mechanical strain-induced Akt phosphorylation was blunted by the PI3K inhibitor wortmannin. Furthermore, cytochalasin D, an inhibitor of actin polymerization, also inhibited the mechanical strain-induced increase in phospho-Akt. These findings imply that mechanical force plays a role in regulating Nanog expression in ES cells through the actin cytoskeleton-PI3K-Akt signaling. -- Highlights: Black-Right-Pointing-Pointer The expression of Nanog, which is an essential regulator of 'stemness' was reduced during embryonic stem (ES) cell differentiation. Black-Right-Pointing-Pointer Cyclic mechanical strain attenuated the reduction of Nanog expression. Black-Right-Pointing-Pointer Cyclic mechanical strain promoted PI3K-Akt signaling and mechanical strain-induced Akt phosphorylation was blunted by the PI3K inhibitor and an inhibitor of actin polymerization.

  1. Cyclic mechanical strain maintains Nanog expression through PI3K/Akt signaling in mouse embryonic stem cells

    International Nuclear Information System (INIS)

    Horiuchi, Rie; Akimoto, Takayuki; Hong, Zhang; Ushida, Takashi

    2012-01-01

    Mechanical strain has been reported to affect the proliferation/differentiation of many cell types; however, the effects of mechanotransduction on self-renewal as well as pluripotency of embryonic stem (ES) cells remains unknown. To investigate the effects of mechanical strain on mouse ES cell fate, we examined the expression of Nanog, which is an essential regulator of self-renewal and pluripotency as well as Nanog-associated intracellular signaling during uniaxial cyclic mechanical strain. The mouse ES cell line, CCE was plated onto elastic membranes, and we applied 10% strain at 0.17 Hz. The expression of Nanog was reduced during ES cell differentiation in response to the withdrawal of leukemia inhibitory factor (LIF); however, two days of cyclic mechanical strain attenuated this reduction of Nanog expression. On the other hand, the cyclic mechanical strain promoted PI3K-Akt signaling, which is reported as an upstream of Nanog transcription. The cyclic mechanical strain-induced Akt phosphorylation was blunted by the PI3K inhibitor wortmannin. Furthermore, cytochalasin D, an inhibitor of actin polymerization, also inhibited the mechanical strain-induced increase in phospho-Akt. These findings imply that mechanical force plays a role in regulating Nanog expression in ES cells through the actin cytoskeleton-PI3K-Akt signaling. -- Highlights: ► The expression of Nanog, which is an essential regulator of “stemness” was reduced during embryonic stem (ES) cell differentiation. ► Cyclic mechanical strain attenuated the reduction of Nanog expression. ► Cyclic mechanical strain promoted PI3K-Akt signaling and mechanical strain-induced Akt phosphorylation was blunted by the PI3K inhibitor and an inhibitor of actin polymerization.

  2. Estrogen receptor beta-selective agonists stimulate calcium oscillations in human and mouse embryonic stem cell-derived neurons.

    Directory of Open Access Journals (Sweden)

    Lili Zhang

    2010-07-01

    Full Text Available Estrogens are used extensively to treat hot flashes in menopausal women. Some of the beneficial effects of estrogens in hormone therapy on the brain might be due to nongenomic effects in neurons such as the rapid stimulation of calcium oscillations. Most studies have examined the nongenomic effects of estrogen receptors (ER in primary neurons or brain slices from the rodent brain. However, these cells can not be maintained continuously in culture because neurons are post-mitotic. Neurons derived from embryonic stem cells could be a potential continuous, cell-based model to study nongenomic actions of estrogens in neurons if they are responsive to estrogens after differentiation. In this study ER-subtype specific estrogens were used to examine the role of ERalpha and ERbeta on calcium oscillations in neurons derived from human (hES and mouse embryonic stem cells. Unlike the undifferentiated hES cells the differentiated cells expressed neuronal markers, ERbeta, but not ERalpha. The non-selective ER agonist 17beta-estradiol (E(2 rapidly increased [Ca2+]i oscillations and synchronizations within a few minutes. No change in calcium oscillations was observed with the selective ERalpha agonist 4,4',4''-(4-Propyl-[1H]-pyrazole-1,3,5-triyltrisphenol (PPT. In contrast, the selective ERbeta agonists, 2,3-bis(4-Hydroxyphenyl-propionitrile (DPN, MF101, and 2-(3-fluoro-4-hydroxyphenyl-7-vinyl-1,3 benzoxazol-5-ol (ERB-041; WAY-202041 stimulated calcium oscillations similar to E(2. The ERbeta agonists also increased calcium oscillations and phosphorylated PKC, AKT and ERK1/2 in neurons derived from mouse ES cells, which was inhibited by nifedipine demonstrating that ERbeta activates L-type voltage gated calcium channels to regulate neuronal activity. Our results demonstrate that ERbeta signaling regulates nongenomic pathways in neurons derived from ES cells, and suggest that these cells might be useful to study the nongenomic mechanisms of estrogenic compounds.

  3. Toxicity of silver nanoparticles in mouse embryonic stem cells and chemical based reprogramming of somatic cells to sphere cells

    Science.gov (United States)

    Rajanahalli Krishnamurthy, Pavan

    Abstract 1: Silver nanoparticles (Ag Np's) have an interesting surface chemistry and unique plasmonic properties. They are used in a wide variety of applications ranging from consumer products like socks, medical dressing, computer chips and it is also shown to have antimicrobial, anti bacterial activity and wound healing. Ag Np toxicity studies have been limited to date which needs to be critically addressed due to its wide applications. Mouse embryonic stem (MES) cells represent a unique cell population with the ability to undergo both self renewal and differentiation. They exhibit very stringent and tightly regulated mechanisms to circumvent DNA damage and stress response. We used 10 nm coated (polysaccharide) and uncoated Ag Np's to test its toxic effects on MES cells. MES cells and embryoid bodies (EB's) were treated with two concentrations of Ag Np's: 5 microg/ml and 50 ug/ml and exposed for 24, 48 and 72 hours. Increased cell death, ROS production and loss of mitochondrial membrane potential and alkaline phosphatase (AP) occur in a time and a concentration dependant manner. Due to increased cell death, there is a progressive increase in Annexin V (apoptosis) and Propidium Iodide (PI) staining (necrosis). Oct4 and Nanog undergo ubiquitination and dephosphorylation post-translational modifications in MES cells thereby altering gene expression of pluripotency factors and differentiation of EB's into all the three embryonic germ layers with specific growth factors were also inhibited after Ag Np exposure. Flow cytometry analysis revealed Ag Np's treated cells had altered cell cycle phases correlating with altered self renewal capacity. Our results suggest that Ag Np's effect MES cell self renewal, pluripotency and differentiation and serves as a perfect model system for studying toxicity induced by engineered Ag Np's. Abstract 2: The reprogramming of fibroblasts to pluripotent stem cells and the direct conversion of fibroblasts to functional neurons has been

  4. Enrichment of cardiac differentiation of mouse embryonic stem cells by optimizing the hanging drop method.

    Science.gov (United States)

    Chen, Ming; Lin, Yong-Qing; Xie, Shuang-Lun; Wu, Hong-Fu; Wang, Jing-Feng

    2011-04-01

    Hanging drop (HD) culture is used to induce differentiation of embryonic stem cells (ESCs) into other cell types including cardiomyocytes. However, the factors affecting cardiac differentiation of ESCs with this method remain incompletely understood. We have investigated the effects of the starting number of ESCs in embryoid bodies (EBs) and the time of EB adherence to gelatin-coated plates on cardiac differentiation: cardiac differentiation was increased in the EBs by a larger number of ESCs and was decreased by plating EBs at day 4 or earlier. These two factors can thus be optimized to enrich the cardiac differentiation in ESCs using the HD method.

  5. Striking a balance: regulation of transposable elements by Zfp281 and Mll2 in mouse embryonic stem cells.

    Science.gov (United States)

    Dai, Qian; Shen, Yang; Wang, Yan; Wang, Xin; Francisco, Joel Celio; Luo, Zhuojuan; Lin, Chengqi

    2017-12-01

    Transposable elements (TEs) compose about 40% of the murine genome. Retrotransposition of active TEs such as LINE-1 (L1) tremendously impacts genetic diversification and genome stability. Therefore, transcription and transposition activities of retrotransposons are tightly controlled. Here, we show that the Krüppel-like zinc finger protein Zfp281 directly binds and suppresses a subset of retrotransposons, including the active young L1 repeat elements, in mouse embryonic stem (ES) cells. In addition, we find that Zfp281-regulated L1s are highly enriched for 5-hydroxymethylcytosine (5hmC) and H3K4me3. The COMPASS-like H3K4 methyltransferase Mll2 is the major H3K4me3 methylase at the Zfp281-regulated L1s and required for their proper expression. Our studies also reveal that Zfp281 functions partially through recruiting the L1 regulators DNA hydroxymethylase Tet1 and Sin3A, and restricting Mll2 at these active L1s, leading to their balanced expression. In summary, our data indicate an instrumental role of Zfp281 in suppressing the young active L1s in mouse ES cells. © The Author(s) 2017. Published by Oxford University Press on behalf of Nucleic Acids Research.

  6. CRISPR reveals a distal super-enhancer required for Sox2 expression in mouse embryonic stem cells.

    Directory of Open Access Journals (Sweden)

    Yan Li

    Full Text Available The pluripotency of embryonic stem cells (ESCs is maintained by a small group of master transcription factors including Oct4, Sox2 and Nanog. These core factors form a regulatory circuit controlling the transcription of a number of pluripotency factors including themselves. Although previous studies have identified transcriptional regulators of this core network, the cis-regulatory DNA sequences required for the transcription of these key pluripotency factors remain to be defined. We analyzed epigenomic data within the 1.5 Mb gene-desert regions around the Sox2 gene and identified a 13kb-long super-enhancer (SE located 100kb downstream of Sox2 in mouse ESCs. This SE is occupied by Oct4, Sox2, Nanog, and the mediator complex, and physically interacts with the Sox2 locus via DNA looping. Using a simple and highly efficient double-CRISPR genome editing strategy we deleted the entire 13-kb SE and characterized transcriptional defects in the resulting monoallelic and biallelic deletion clones with RNA-seq. We showed that the SE is responsible for over 90% of Sox2 expression, and Sox2 is the only target gene along the chromosome. Our results support the functional significance of a SE in maintaining the pluripotency transcription program in mouse ESCs.

  7. Evaluation of hollow fiber culture for large-scale production of mouse embryonic stem cell-derived hematopoietic stem cells.

    Science.gov (United States)

    Nakano, Yu; Iwanaga, Shinya; Mizumoto, Hiroshi; Kajiwara, Toshihisa

    2018-03-03

    Hematopoietic stem cells (HSCs) have the ability to differentiate into all types of blood cells and can be transplanted to treat blood disorders. However, it is difficult to obtain HSCs in large quantities because of the shortage of donors. Recent efforts have focused on acquiring HSCs by differentiation of pluripotent stem cells. As a conventional differentiation method of pluripotent stem cells, the formation of embryoid bodies (EBs) is often employed. However, the size of EBs is limited by depletion of oxygen and nutrients, which prevents them from being efficient for the production of HSCs. In this study, we developed a large-scale hematopoietic differentiation approach for mouse embryonic stem (ES) cells by applying a hollow fiber (HF)/organoid culture method. Cylindrical organoids, which had the potential for further spontaneous differentiation, were established inside of hollow fibers. Using this method, we improved the proliferation rate of mouse ES cells to produce an increased HSC population and achieved around a 40-fold higher production volume of HSCs in HF culture than in conventional EB culture. Therefore, the HF/organoid culture method may be a new mass culture method to acquire pluripotent stem cell-derived HSCs.

  8. Expression of interleukin-17B in mouse embryonic limb buds and regulation by BMP-7 and bFGF

    International Nuclear Information System (INIS)

    You Zongbing; DuRaine, Grayson; Tien, Janet Y.L.; Lee, Corinne; Moseley, Timothy A.; Reddi, A. Hari

    2005-01-01

    Interleukin-17B (IL-17B) is a member of interleukin-17 family that displays a variety of proinflammatory and immune modulatory activities. In this study, we found that IL-17B mRNA was maximally expressed in the limb buds of 14.5 days post coitus (dpc) mouse embryo and declined to low level at 19.5 dpc. By immunohistochemical staining, the strongest IL-17B signals were observed in the cells of the bone collar in the primary ossification center. The chondrocytes in the resting and proliferative zones were stained moderately, while little staining was seen in the hypertrophic zone. Furthermore, in both C3H10T1/2 and MC3T3-E1 cells, the IL-17B mRNA was up-regulated by recombinant human bone morphogenetic protein-7, but down-regulated by basic fibroblast growth factor via the extracellular signal-regulated kinase pathway. This study provides the first evidence that IL-17B is expressed in the mouse embryonic limb buds and may play a role in chondrogenesis and osteogenesis

  9. Emil Selenka on the embryonic membranes of the mouse and placentation in gibbons and orangutans

    DEFF Research Database (Denmark)

    Carter, A M; Pijnenborg, R

    2016-01-01

    BACKGROUND: Emil Selenka made important contributions to embryology in marsupials, rodents and primates that deserve wider recognition. Here we review his work on early development of the mouse and placentation in the great apes. FINDINGS: Selenka was intrigued by germ layer theory, which led him...... to study inversion of the germ layers in the mouse and other rodents. He found it was growth of the ectoplacental cone that caused a downward shift in the position of the underlying ectoderm and endoderm, leading to an inside-outside inversion of these layers. In primates he made the important discovery...

  10. Tankyrase 1 and tankyrase 2 are essential but redundant for mouse embryonic development.

    Directory of Open Access Journals (Sweden)

    Y Jeffrey Chiang

    2008-07-01

    Full Text Available Tankyrases are proteins with poly(ADP-ribose polymerase activity. Human tankyrases post-translationally modify multiple proteins involved in processes including maintenance of telomere length, sister telomere association, and trafficking of glut4-containing vesicles. To date, however, little is known about in vivo functions for tankyrases. We recently reported that body size was significantly reduced in mice deficient for tankyrase 2, but that these mice otherwise appeared developmentally normal. In the present study, we report generation of tankyrase 1-deficient and tankyrase 1 and 2 double-deficient mice, and use of these mutant strains to systematically assess candidate functions of tankyrase 1 and tankyrase 2 in vivo. No defects were observed in development, telomere length maintenance, or cell cycle regulation in tankyrase 1 or tankyrase 2 knockout mice. In contrast to viability and normal development of mice singly deficient in either tankyrase, deficiency in both tankyrase 1 and tankyrase 2 results in embryonic lethality by day 10, indicating that there is substantial redundancy between tankyrase 1 and tankyrase 2, but that tankyrase function is essential for embryonic development.

  11. Fate of D3 mouse embryonic stem cells exposed to X-rays or carbon ions.

    Science.gov (United States)

    Luft, S; Pignalosa, D; Nasonova, E; Arrizabalaga, O; Helm, A; Durante, M; Ritter, S

    2014-01-15

    The risk of radiation exposure during embryonic development is still a major problem in radiotoxicology. In this study we investigated the response of the murine embryonic stem cell (mESC) line D3 to two radiation qualities: sparsely ionizing X-rays and densely ionizing carbon ions. We analyzed clonogenic cell survival, proliferation, induction of chromosome aberrations as well as the capability of cells to differentiate to beating cardiomyocytes up to 3 days after exposure. Our results show that, for all endpoints investigated, carbon ions are more effective than X-rays at the same radiation dose. Additionally, in long term studies (≥8 days post-irradiation) chromosomal damage and the pluripotency state were investigated. These studies reveal that pluripotency markers are present in the progeny of cells surviving the exposure to both radiation types. However, only in the progeny of X-ray exposed cells the aberration frequency was comparable to that of the control population, while the progeny of carbon ion irradiated cells harbored significantly more aberrations than the control, generally translocations. We conclude that cells surviving the radiation exposure maintain pluripotency but may carry stable chromosomal rearrangements after densely ionizing radiation. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. Reproductive effects of two neonicotinoid insecticides on mouse sperm function and early embryonic development in vitro.

    Directory of Open Access Journals (Sweden)

    Yi-Hua Gu

    Full Text Available Acetamiprid (ACE and imidacloprid (IMI are two major members in the family of neonicotinoid pesticides, which are synthesized with a higher selectivity to insects. The present study determined and compared in vitro effects of ACE, IMI and nicotine on mammalian reproduction by using an integrated testing strategy for reproductive toxicology, which covered sperm quality, sperm penetration into oocytes and preimplantation embryonic development. Direct chemical exposure (500 µM or 5 mM on spermatozoa during capacitation was performed, and in vitro fertilization (IVF process, zygotes and 2-cell embryos were respectively incubated with chemical-supplemented medium until blastocyst formation to evaluate the reproductive toxicity of these chemicals and monitor the stages mainly affected. Generally, treatment of 500 µM or 5 mM chemicals for 30 min did not change sperm motility and DNA integrity significantly but the fertilization ability in in vitro fertilization (IVF process, indicating that IVF process could detect and distinguish subtle effect of spermatozoa exposed to different chemicals. Culture experiment in the presence of chemicals in medium showed that fertilization process and zygotes are adversely affected by direct exposure of chemicals (PIMI>ACE, whereas developmental progression of 2-cell stage embryos was similar to controls (P>0.05. These findings unveiled the hazardous effects of neonicotinoid pesticides exposure on mammalian sperm fertilization ability as well as embryonic development, raising the concerns that neonicotinoid pesticides may pose reproductive risks on human reproductive health, especially in professional populations.

  13. Characterizing embryonic gene expression patterns in the mouse using nonredundant sequence-based selection

    DEFF Research Database (Denmark)

    Sousa-Nunes, Rita; Rana, Amer Ahmed; Kettleborough, Ross

    2003-01-01

    This article investigates the expression patterns of 160 genes that are expressed during early mouse development. The cDNAs were isolated from 7.5 d postcoitum (dpc) endoderm, a region that comprises visceral endoderm (VE), definitive endoderm, and the node-tissues that are required for the initi...

  14. Mesenchymal and embryonic characteristics of stem cells obtained from mouse dental pulp

    DEFF Research Database (Denmark)

    Guimarães, Elisalva Teixeira; Cruz, Gabriela Silva; de Jesus, Alan Araújo

    2011-01-01

    abnormalities was evaluated by G banding. RESULTS: The mouse dental pulp stem cells (mDPSC) were highly proliferative, plastic-adherent, and exhibited a polymorphic morphology predominantly with stellate or fusiform shapes. The presence of cell clusters was observed in cultures of mDPSC. Some cells were...

  15. Culture conditions have an impact on the maturation of traceable, transplantable mouse embryonic stem cell-derived otic progenitor cells.

    Science.gov (United States)

    Abboud, Nesrine; Fontbonne, Arnaud; Watabe, Isabelle; Tonetto, Alain; Brezun, Jean Michel; Feron, François; Zine, Azel

    2017-09-01

    The generation of replacement inner ear hair cells (HCs) remains a challenge and stem cell therapy holds the potential for developing therapeutic solutions to hearing and balance disorders. Recent developments have made significant strides in producing mouse otic progenitors using cell culture techniques to initiate HC differentiation. However, no consensus has been reached as to efficiency and therefore current methods remain unsatisfactory. In order to address these issues, we compare the generation of otic and HC progenitors from embryonic stem (ES) cells in two cell culture systems: suspension vs. adherent conditions. In the present study, an ES cell line derived from an Atoh1-green fluorescent protein (GFP) transgenic mouse was used to track the generation of otic progenitors, initial HCs and to compare these two differentiation systems. We used a two-step short-term differentiation method involving an induction period of 5 days during which ES cells were cultured in the presence of Wnt/transforming growth factor TGF-β inhibitors and insulin-like growth factor IGF-1 to suppress mesoderm and reinforce presumptive ectoderm and otic lineages. The generated embryoid bodies were then differentiated in medium containing basic fibroblast growth factor (bFGF) for an additional 5 days using either suspension or adherent culture methods. Upon completion of differentiation, quantitative polymerase chain reaction analysis and immunostaining monitored the expression of otic/HC progenitor lineage markers. The results indicate that cells differentiated in suspension cultures produced cells expressing otic progenitor/HC markers at a higher efficiency compared with the production of these cell types within adherent cultures. Furthermore, we demonstrated that a fraction of these cells can incorporate into ototoxin-injured mouse postnatal cochlea explants and express MYO7A after transplantation. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons

  16. Derivation of Traceable and Transplantable Photoreceptors from Mouse Embryonic Stem Cells

    Directory of Open Access Journals (Sweden)

    Sarah Decembrini

    2014-06-01

    Full Text Available Retinal degenerative diseases resulting in the loss of photoreceptors are one of the major causes of blindness. Photoreceptor replacement therapy is a promising treatment because the transplantation of retina-derived photoreceptors can be applied now to different murine retinopathies to restore visual function. To have an unlimited source of photoreceptors, we derived a transgenic embryonic stem cell (ESC line in which the Crx-GFP transgene is expressed in photoreceptors and assessed the capacity of a 3D culture protocol to produce integration-competent photoreceptors. This culture system allows the production of a large number of photoreceptors recapitulating the in vivo development. After transplantation, integrated cells showed the typical morphology of mature rods bearing external segments and ribbon synapses. We conclude that a 3D protocol coupled with ESCs provides a safe and renewable source of photoreceptors displaying a development and transplantation competence comparable to photoreceptors from age-matched retinas.

  17. Binge consumption of ethanol during pregnancy leads to significant developmental delay of mouse embryonic brain

    Science.gov (United States)

    Sudheendran, Narendran; Bake, Shameena; Miranda, Rajesh C.; Larin, Kirill V.

    2014-03-01

    Consumption of alcohol during pregnancy can be severely detrimental to the development of the brain in fetuses. This study explores the usage of optical coherence tomography (OCT) to the study the effects of maternal consumption of ethanol on brain development in mouse fetuses. On gestational day 14.5, fetuses were collected and fixed in 4% paraformaldehyde. A swept-source OCT (SSOCT) system was used to acquire 3D images of the brain of ethanol-exposed and control fetuses. The volume of right and left brain ventricles were measured and used to compare between ethanol-exposed and control fetuses. A total of 5 fetuses were used for each of the two groups. The average volumes of the right and left ventricles were measured to be 0.35 and 0.15 mm3 for ethanol-exposed and control fetuses, respectively. The results demonstrated that there is an alcohol-induced developmental delay in mouse fetal brains.

  18. Correlation between DNA repair of embryonic fibroblasts and different life span of 3 inbred mouse strains

    Energy Technology Data Exchange (ETDEWEB)

    Paffenholz, V.

    1978-02-01

    Primary mouse fibroblast cultures were established from 10 day old embryos of 3 inbred strains with a genetically determined different life expectancy. The capacity for unscheduled DNA synthesis following uv irradiation was studied in these cells at various passage levels of the in vitro ageing process. The mouse fibroblasts show considerable repair synthesis corresponding to the duration of exposure time. The capacity for induction of unscheduled DNA synthesis was different in the cells of each strain and correlated to the natural life span of the animal. In each case, however, the ability to perform repair synthesis was subjected to an age-associated decline, although semiconservative DNA synthesis and proliferative potential of the cell was not changed until the cultures entered phase III passages.

  19. Genomic targets of Brachyury (T in differentiating mouse embryonic stem cells.

    Directory of Open Access Journals (Sweden)

    Amanda L Evans

    Full Text Available The T-box transcription factor Brachyury (T is essential for formation of the posterior mesoderm and the notochord in vertebrate embryos. Work in the frog and the zebrafish has identified some direct genomic targets of Brachyury, but little is known about Brachyury targets in the mouse.Here we use chromatin immunoprecipitation and mouse promoter microarrays to identify targets of Brachyury in embryoid bodies formed from differentiating mouse ES cells. The targets we identify are enriched for sequence-specific DNA binding proteins and include components of signal transduction pathways that direct cell fate in the primitive streak and tailbud of the early embryo. Expression of some of these targets, such as Axin2, Fgf8 and Wnt3a, is down regulated in Brachyury mutant embryos and we demonstrate that they are also Brachyury targets in the human. Surprisingly, we do not observe enrichment of the canonical T-domain DNA binding sequence 5'-TCACACCT-3' in the vicinity of most Brachyury target genes. Rather, we have identified an (AC(n repeat sequence, which is conserved in the rat but not in human, zebrafish or Xenopus. We do not understand the significance of this sequence, but speculate that it enhances transcription factor binding in the regulatory regions of Brachyury target genes in rodents.Our work identifies the genomic targets of a key regulator of mesoderm formation in the early mouse embryo, thereby providing insights into the Brachyury-driven genetic regulatory network and allowing us to compare the function of Brachyury in different species.

  20. Cell-type-specific predictive network yields novel insights into mouse embryonic stem cell self-renewal and cell fate.

    Directory of Open Access Journals (Sweden)

    Karen G Dowell

    Full Text Available Self-renewal, the ability of a stem cell to divide repeatedly while maintaining an undifferentiated state, is a defining characteristic of all stem cells. Here, we clarify the molecular foundations of mouse embryonic stem cell (mESC self-renewal by applying a proven Bayesian network machine learning approach to integrate high-throughput data for protein function discovery. By focusing on a single stem-cell system, at a specific developmental stage, within the context of well-defined biological processes known to be active in that cell type, we produce a consensus predictive network that reflects biological reality more closely than those made by prior efforts using more generalized, context-independent methods. In addition, we show how machine learning efforts may be misled if the tissue specific role of mammalian proteins is not defined in the training set and circumscribed in the evidential data. For this study, we assembled an extensive compendium of mESC data: ∼2.2 million data points, collected from 60 different studies, under 992 conditions. We then integrated these data into a consensus mESC functional relationship network focused on biological processes associated with embryonic stem cell self-renewal and cell fate determination. Computational evaluations, literature validation, and analyses of predicted functional linkages show that our results are highly accurate and biologically relevant. Our mESC network predicts many novel players involved in self-renewal and serves as the foundation for future pluripotent stem cell studies. This network can be used by stem cell researchers (at http://StemSight.org to explore hypotheses about gene function in the context of self-renewal and to prioritize genes of interest for experimental validation.

  1. Perfluorooctane sulfonate disturbs Nanog expression through miR-490-3p in mouse embryonic stem cells.

    Directory of Open Access Journals (Sweden)

    Bo Xu

    Full Text Available Perfluorooctane sulfonate (PFOS poses potential risks to reproduction and development. Mouse embryonic stem cells (mESCs are ideal models for developmental toxicity testing of environmental contaminants in vitro. However, the mechanism by which PFOS affects early embryonic development is still unclear. In this study, mESCs were exposed to PFOS for 24 h, and then general cytotoxicity and pluripotency were evaluated. MTT assay showed that neither PFOS (0.2 µM, 2 µM, 20 µM, and 200 µM nor control medium (0.1% DMSO treatments affected cell viability. Furthermore, there were no significant differences in cell cycle and apoptosis between the PFOS treatment and control groups. However, we found that the mRNA and protein levels of pluripotency markers (Sox2, Nanog in mESCs were significantly decreased following exposure to PFOS for 24 h, while there were no significant changes in the mRNA and protein levels of Oct4. Accordingly, the expression levels of miR-145 and miR-490-3p, which can regulate Sox2 and Nanog expressions were significantly increased. Chrm2, the host gene of miR-490-3p, was positively associated with miR-490-3p expression after PFOS exposure. Dual luciferase reporter assay suggests that miR-490-3p directly targets Nanog. These results suggest that PFOS can disturb the expression of pluripotency factors in mESCs, while miR-145 and miR-490-3p play key roles in modulating this effect.

  2. Myc Decoy Oligodeoxynucleotide Inhibits Growth and Modulates Differentiation of Mouse Embryonic Stem Cells as a Model of Cancer Stem Cells.

    Science.gov (United States)

    Johari, Behrooz; Ebrahimi-Rad, Mina; Maghsood, Faezeh; Lotfinia, Majid; Saltanatpouri, Zohreh; Teimoori-Toolabi, Ladan; Sharifzadeh, Zahra; Karimipoor, Morteza; Kadivar, Mehdi

    2017-01-01

    Myc (c-Myc) alone activates the embryonic stem cell-like transcriptional module in both normal and transformed cells. Its dysregulation might lead to increased cancer stem cells (CSCs) population in some tumor cells. In order to investigate the potential of Myc decoy oligodeoxynucleotides for differentiation therapy, mouse embryonic stem cells (mESCs) were used in this study as a model of CSCs. To our best of knowledge this is the first report outlining the application of Myc decoy in transcription factor decoy "TFD" strategy for inducing differentiation in mESCs. A 20-mer double-stranded Myc transcription factor decoy and scrambled oligodeoxynucleotides (ODNs) were designed, analyzed by electrophoretic mobility shift (EMSA) assay and transfected into the mESCs under 2 inhibitors (2i) condition. Further investigations were carried out using fluorescence and confocal microscopy, cell proliferation and apoptosis analysis, alkaline phosphatase and embryoid body formation assay, real-time PCR and western blotting. EMSA data showed that Myc decoy ODNs bound specifically to c-Myc protein. They were found to be localized in both cytoplasm and nucleus of mESCs. Our results revealed the potential capability of Myc decoy ODNs to decrease cell viability by (16.1±2%), to increase the number of cells arrested in G0/G1 phases and apoptosis by (14.2±3.1%) and (12.1±3.2%), respectively regarding the controls. Myc decoy could also modulate differentiation in mESCs despite the presence of 2i/LIF in our medium the presence of 2i/LIF in our medium. The optimized Myc decoy ODNs approach might be considered as a promising alternative strategy for differentiation therapy investigations. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  3. Anterograde Tracing Method using DiI to Label Vagal Innervation of the Embryonic and Early Postnatal Mouse Gastrointestinal Tract

    Science.gov (United States)

    Murphy, Michelle C.; Fox, Edward A.

    2007-01-01

    The mouse is an extremely valuable model for studying vagal development in relation to strain differences, genetic variation, gene manipulations, or pharmacological manipulations. Therefore, a method using 1, 1′-dioctadecyl-3,3,3′,3′-tetramethylindocarbocyanine perchlorate (DiI) was developed for labeling vagal innervation of the gastrointestinal (GI) tract in embryonic and postnatal mice. DiI labeling was adapted and optimized for this purpose by varying several facets of the method. For example, insertion and crushing of DiI crystals into the nerve led to faster DiI diffusion along vagal axons and diffusion over longer distances as compared with piercing the nerve with a micropipette tip coated with dried DiI oil. Moreover, inclusion of EDTA in the fixative reduced leakage of DiI out of nerve fibers that occurred with long incubations. Also, mounting labeled tissue in PBS was superior to glycerol with n-propyl gallate, which resulted in reduced clarity of DiI labeling that may have been due to DiI leaking out of fibers. Optical sectioning of flattened wholemounts permitted examination of individual tissue layers of the GI tract wall. This procedure aided identification of nerve ending types because in most instances each type innervates a different tissue layer. Between embryonic day 12.5 and postnatal day 8, growth of axons into the GI tract, formation and patterning of fiber bundles in the myenteric plexus and early formation of putative afferent and efferent nerve terminals were observed. Thus, the DiI tracing method developed here has opened up a window for investigation during an important phase of vagal development. PMID:17418900

  4. Evaluation of 309 environmental chemicals using a mouse embryonic stem cell adherent cell differentiation and cytotoxicity assay.

    Directory of Open Access Journals (Sweden)

    Kelly J Chandler

    Full Text Available The vast landscape of environmental chemicals has motivated the need for alternative methods to traditional whole-animal bioassays in toxicity testing. Embryonic stem (ES cells provide an in vitro model of embryonic development and an alternative method for assessing developmental toxicity. Here, we evaluated 309 environmental chemicals, mostly food-use pesticides, from the ToxCast™ chemical library using a mouse ES cell platform. ES cells were cultured in the absence of pluripotency factors to promote spontaneous differentiation and in the presence of DMSO-solubilized chemicals at different concentrations to test the effects of exposure on differentiation and cytotoxicity. Cardiomyocyte differentiation (α,β myosin heavy chain; MYH6/MYH7 and cytotoxicity (DRAQ5™/Sapphire700™ were measured by In-Cell Western™ analysis. Half-maximal activity concentration (AC₅₀ values for differentiation and cytotoxicity endpoints were determined, with 18% of the chemical library showing significant activity on either endpoint. Mining these effects against the ToxCast Phase I assays (∼500 revealed significant associations for a subset of chemicals (26 that perturbed transcription-based activities and impaired ES cell differentiation. Increased transcriptional activity of several critical developmental genes including BMPR2, PAX6 and OCT1 were strongly associated with decreased ES cell differentiation. Multiple genes involved in reactive oxygen species signaling pathways (NRF2, ABCG2, GSTA2, HIF1A were strongly associated with decreased ES cell differentiation as well. A multivariate model built from these data revealed alterations in ABCG2 transporter was a strong predictor of impaired ES cell differentiation. Taken together, these results provide an initial characterization of metabolic and regulatory pathways by which some environmental chemicals may act to disrupt ES cell growth and differentiation.

  5. Expression and loss of alleles in cultured mouse embryonic fibroblasts and stem cells carrying allelic fluorescent protein genes

    Directory of Open Access Journals (Sweden)

    Stringer Saundra L

    2006-10-01

    Full Text Available Abstract Background Loss of heterozygosity (LOH contributes to many cancers, but the rate at which these events occur in normal cells of the body is not clear. LOH would be detectable in diverse cell types in the body if this event were to confer an obvious cellular phenotype. Mice that carry two different fluorescent protein genes as alleles of a locus would seem to be a useful tool for addressing this issue because LOH would change a cell's phenotype from dichromatic to monochromatic. In addition, LOH caused by mitotic crossing over might be discernable in tissues because this event produces a pair of neighboring monochromatic cells that are different colors. Results As a step in assessing the utility of this approach, we derived primary embryonic fibroblast populations and embryonic stem cell lines from mice that carried two different fluorescent protein genes as alleles at the chromosome 6 locus, ROSA26. Fluorescence activated cell sorting (FACS showed that the vast majority of cells in each line expressed the two marker proteins at similar levels, and that populations exhibited expression noise similar to that seen in bacteria and yeast. Cells with a monochromatic phenotype were present at frequencies on the order of 10-4 and appeared to be produced at a rate of approximately 10-5 variant cells per mitosis. 45 of 45 stably monochromatic ES cell clones exhibited loss of the expected allele at the ROSA26 locus. More than half of these clones retained heterozygosity at a locus between ROSA26 and the centromere. Other clones exhibited LOH near the centromere, but were disomic for chromosome 6. Conclusion Allelic fluorescent markers allowed LOH at the ROSA26 locus to be detected by FACS. LOH at this locus was usually not accompanied by LOH near the centromere, suggesting that mitotic recombination was the major cause of ROSA26 LOH. Dichromatic mouse embryonic cells provide a novel system for studying genetic/karyotypic stability and factors

  6. Single cell analysis facilitates staging of Blimp1-dependent primordial germ cells derived from mouse embryonic stem cells.

    Directory of Open Access Journals (Sweden)

    John J Vincent

    Full Text Available The cell intrinsic programming that regulates mammalian primordial germ cell (PGC development in the pre-gonadal stage is challenging to investigate. To overcome this we created a transgene-free method for generating PGCs in vitro (iPGCs from mouse embryonic stem cells (ESCs. Using labeling for SSEA1 and cKit, two cell surface molecules used previously to isolate presumptive iPGCs, we show that not all SSEA1+/cKit+ double positive cells exhibit a PGC identity. Instead, we determined that selecting for cKit(bright cells within the SSEA1+ fraction significantly enriches for the putative iPGC population. Single cell analysis comparing SSEA1+/cKit(bright iPGCs to ESCs and embryonic PGCs demonstrates that 97% of single iPGCs co-express PGC signature genes Blimp1, Stella, Dnd1, Prdm14 and Dazl at similar levels to e9.5-10.5 PGCs, whereas 90% of single mouse ESC do not co-express PGC signature genes. For the 10% of ESCs that co-express PGC signature genes, the levels are significantly lower than iPGCs. Microarray analysis shows that iPGCs are transcriptionally distinct from ESCs and repress gene ontology groups associated with mesoderm and heart development. At the level of chromatin, iPGCs contain 5-methyl cytosine bases in their DNA at imprinted and non-imprinted loci, and are enriched in histone H3 lysine 27 trimethylation, yet do not have detectable levels of Mvh protein, consistent with a Blimp1-positive pre-gonadal PGC identity. In order to determine whether iPGC formation is dependent upon Blimp1, we generated Blimp1 null ESCs and found that loss of Blimp1 significantly depletes SSEA1/cKit(bright iPGCs. Taken together, the generation of Blimp1-positive iPGCs from ESCs constitutes a robust model for examining cell-intrinsic regulation of PGCs during the Blimp1-positive stage of development.

  7. Sodium fluoride induces apoptosis in mouse embryonic stem cells through ROS-dependent and caspase- and JNK-mediated pathways

    International Nuclear Information System (INIS)

    Nguyen Ngoc, Tam Dan; Son, Young-Ok; Lim, Shin-Saeng; Shi, Xianglin; Kim, Jong-Ghee; Heo, Jung Sun; Choe, Youngji; Jeon, Young-Mi; Lee, Jeong-Chae

    2012-01-01

    Sodium fluoride (NaF) is used as a source of fluoride ions in diverse applications. Fluoride salt is an effective prophylactic for dental caries and is an essential element required for bone health. However, fluoride is known to cause cytotoxicity in a concentration-dependent manner. Further, no information is available on the effects of NaF on mouse embryonic stem cells (mESCs). We investigated the mode of cell death induced by NaF and the mechanisms involved. NaF treatment greater than 1 mM reduced viability and DNA synthesis in mESCs and induced cell cycle arrest in the G 2 /M phase. The addition of NaF induced cell death mainly by apoptosis rather than necrosis. Catalase (CAT) treatment significantly inhibited the NaF-mediated cell death and also suppressed the NaF-mediated increase in phospho-c-Jun N-terminal kinase (p-JNK) levels. Pre-treatment with SP600125 or z-VAD-fmk significantly attenuated the NaF-mediated reduction in cell viability. In contrast, intracellular free calcium chelator, but not of sodium or calcium ion channel blockers, facilitated NaF-induced toxicity in the cells. A JNK specific inhibitor (SP600125) prevented the NaF-induced increase in growth arrest and the DNA damage-inducible protein 45α. Further, NaF-mediated loss of mitochondrial membrane potential was apparently inhibited by pifithrin-α or CAT inhibitor. These findings suggest that NaF affects viability of mESCs in a concentration-dependent manner, where more than 1 mM NaF causes apoptosis through hydroxyl radical-dependent and caspase- and JNK-mediated pathways. -- Highlights: ► The mode of NaF-induced cell death and the mechanisms involved were examined. ► NaF induced mainly apoptotic death of mouse embryonic stem cells (mESCs). ► NaF induced mitochondrial-mediated and caspase-dependent apoptosis. ► JNK- and p53-mediated pathways are involved in NaF-mediated apoptosis in the cells. ► ROS are the up-stream effector in NaF-mediated activation of JNK and p53 in mESCs.

  8. Sodium fluoride induces apoptosis in mouse embryonic stem cells through ROS-dependent and caspase- and JNK-mediated pathways

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen Ngoc, Tam Dan [Institute of Oral Biosciences and School of Dentistry (BK21 Program), Chonbuk National University, Jeonju 561-756 (Korea, Republic of); Son, Young-Ok [Graduate Center for Toxicology, School of Medicine, University of Kentucky, Lexington, KY 40536-0305 (United States); Lim, Shin-Saeng [Institute of Oral Biosciences and School of Dentistry (BK21 Program), Chonbuk National University, Jeonju 561-756 (Korea, Republic of); Department of Bioactive Material Sciences and Research Center of Bioactive Materials, Chonbuk National University, Jeonju 561-756 (Korea, Republic of); Shi, Xianglin [Graduate Center for Toxicology, School of Medicine, University of Kentucky, Lexington, KY 40536-0305 (United States); Kim, Jong-Ghee [Institute of Oral Biosciences and School of Dentistry (BK21 Program), Chonbuk National University, Jeonju 561-756 (Korea, Republic of); Heo, Jung Sun [Department of Maxillofacial Biomedical Engineering and Institute of Oral Biology, School of Dentistry, Kyung Hee University, Seoul 130-701 (Korea, Republic of); Choe, Youngji [Institute of Oral Biosciences and School of Dentistry (BK21 Program), Chonbuk National University, Jeonju 561-756 (Korea, Republic of); Jeon, Young-Mi, E-mail: young@jbnu.ac.kr [Institute of Oral Biosciences and School of Dentistry (BK21 Program), Chonbuk National University, Jeonju 561-756 (Korea, Republic of); Lee, Jeong-Chae, E-mail: leejc88@jbnu.ac.kr [Institute of Oral Biosciences and School of Dentistry (BK21 Program), Chonbuk National University, Jeonju 561-756 (Korea, Republic of); Graduate Center for Toxicology, School of Medicine, University of Kentucky, Lexington, KY 40536-0305 (United States); Department of Bioactive Material Sciences and Research Center of Bioactive Materials, Chonbuk National University, Jeonju 561-756 (Korea, Republic of)

    2012-03-15

    Sodium fluoride (NaF) is used as a source of fluoride ions in diverse applications. Fluoride salt is an effective prophylactic for dental caries and is an essential element required for bone health. However, fluoride is known to cause cytotoxicity in a concentration-dependent manner. Further, no information is available on the effects of NaF on mouse embryonic stem cells (mESCs). We investigated the mode of cell death induced by NaF and the mechanisms involved. NaF treatment greater than 1 mM reduced viability and DNA synthesis in mESCs and induced cell cycle arrest in the G{sub 2}/M phase. The addition of NaF induced cell death mainly by apoptosis rather than necrosis. Catalase (CAT) treatment significantly inhibited the NaF-mediated cell death and also suppressed the NaF-mediated increase in phospho-c-Jun N-terminal kinase (p-JNK) levels. Pre-treatment with SP600125 or z-VAD-fmk significantly attenuated the NaF-mediated reduction in cell viability. In contrast, intracellular free calcium chelator, but not of sodium or calcium ion channel blockers, facilitated NaF-induced toxicity in the cells. A JNK specific inhibitor (SP600125) prevented the NaF-induced increase in growth arrest and the DNA damage-inducible protein 45α. Further, NaF-mediated loss of mitochondrial membrane potential was apparently inhibited by pifithrin-α or CAT inhibitor. These findings suggest that NaF affects viability of mESCs in a concentration-dependent manner, where more than 1 mM NaF causes apoptosis through hydroxyl radical-dependent and caspase- and JNK-mediated pathways. -- Highlights: ► The mode of NaF-induced cell death and the mechanisms involved were examined. ► NaF induced mainly apoptotic death of mouse embryonic stem cells (mESCs). ► NaF induced mitochondrial-mediated and caspase-dependent apoptosis. ► JNK- and p53-mediated pathways are involved in NaF-mediated apoptosis in the cells. ► ROS are the up-stream effector in NaF-mediated activation of JNK and p53 in mESCs.

  9. Layered double hydroxide nanoparticles promote self-renewal of mouse embryonic stem cells through the PI3K signaling pathway

    Science.gov (United States)

    Wu, Youjun; Zhu, Rongrong; Zhou, Yang; Zhang, Jun; Wang, Wenrui; Sun, Xiaoyu; Wu, Xianzheng; Cheng, Liming; Zhang, Jing; Wang, Shilong

    2015-06-01

    Embryonic stem cells (ESCs) hold great potential for regenerative medicine due to their two unique characteristics: self-renewal and pluripotency. Several groups of nanoparticles have shown promising applications in directing the stem cell fate. Herein, we investigated the cellular effects of layered double hydroxide nanoparticles (LDH NPs) on mouse ESCs (mESCs) and the associated molecular mechanisms. Mg-Al-LDH NPs with an average diameter of ~100 nm were prepared by hydrothermal methods. To determine the influences of LDH NPs on mESCs, cellular cytotoxicity, self-renewal, differentiation potential, and the possible signaling pathways were explored. Evaluation of cell viability, lactate dehydrogenase release, ROS generation and apoptosis demonstrated the low cytotoxicity of LDH NPs. The alkaline phosphatase activity and the expression of pluripotency genes in mESCs were examined, which indicated that exposure to LDH NPs could support self-renewal and inhibit spontaneous differentiation of mESCs under feeder-free culture conditions. The self-renewal promotion was further proved to be independent of the leukemia inhibitory factor (LIF). Furthermore, cells treated with LDH NPs maintained the potential to differentiate into all three germ layers both in vitro and in vivo through formation of embryoid bodies and teratomas. In addition, we observed that LDH NPs initiated the activation of the PI3K/Akt pathway, while treatment with the PI3K inhibitor LY294002 could block the effects of LDH NPs on mESCs. The results confirmed that the promotion of self-renewal by LDH NPs was associated with activation of the PI3K/Akt signaling pathway. Altogether, our studies identified a new role of LDH NPs in maintaining self-renewal of mouse ES cells which could potentially be applied in stem cell research.Embryonic stem cells (ESCs) hold great potential for regenerative medicine due to their two unique characteristics: self-renewal and pluripotency. Several groups of nanoparticles

  10. Differentiating Mouse Embryonic Stem Cells into Embryoid Bodies by Hanging-Drop Cultures.

    Science.gov (United States)

    Behringer, Richard; Gertsenstein, Marina; Nagy, Kristina Vintersten; Nagy, Andras

    2016-12-01

    Embryonic stem (ES) cells can develop into many types of differentiated tissues if they are placed into a differentiating environment. This can occur in vivo when the ES cells are injected into or aggregated with an embryo, or in vitro if their culture conditions are modified to induce differentiation. There are an increasing number of differentiating culture conditions that can bias the differentiation of ES cells into desired cell types. Determining the mechanisms that control ES cell differentiation into therapeutically important cell types is a quickly growing area of research. Knowledge gained from these studies may eventually lead to the use of stem cells to repair specific damaged tissues. Many times ES cell differentiation proceeds through an intermediate stage called the embryoid body (EB). EBs are round structures composed of ES cells that have undergone some of the initial stages of differentiation. EBs can then be manipulated further to generate more specific cell types. This protocol describes a method to differentiate ES cells into EBs. It produces EBs of comparable size. This aspect is important because the differentiation processes taking place inside an EB are influenced by its size. © 2016 Cold Spring Harbor Laboratory Press.

  11. In vitro differentiation of mouse embryonic stem (mES) cells using the hanging drop method.

    Science.gov (United States)

    Wang, Xiang; Yang, Phillip

    2008-07-23

    Stem cells have the remarkable potential to develop into many different cell types. When a stem cell divides, each new cell has the potential to either remain a stem cell or become another type of cell with a more specialized function, This promising of science is leading scientists to investigate the possibility of cell-based therapies to treat disease. When culture in suspension without antidifferentiation factors, embryonic stem cells spontaneously differentiate and form three-dimensional multicellular aggregates. These cell aggregates are called embryoid bodies(EB). Hanging drop culture is a widely used EB formation induction method. The rounded bottom of hanging drop allows the aggregation of ES cells which can provide mES cells a good environment for forming EBs. The number of ES cells aggregatied in a hanging drop can be controlled by varying the number of cells in the initial cell suspension to be hung as a drop from the lid of Petri dish. Using this method we can reproducibly form homogeneous EBs from a predetermined number of ES cells.

  12. Marked accumulation of valproic acid in embryonic neuroepithelium of the mouse during early organogenesis

    International Nuclear Information System (INIS)

    Dencker, L.; Nau, H.; D'Argy, R.

    1990-01-01

    Valproic acid, an antiepileptic drug, causes neural tube defects in mice and man. 14C-labeled valproic acid (sodium-salt) was administered to pregnant mice on days 8 and 9 of gestation (period of high sensitivity in regard to formation of neural tube defects in this species). Two dose levels of valproic acid (1 and 400 mg/kg) were used; in each case the total radioactivity administered was the same: 400 microCi/kg or 14.7 MBq/kg. Autoradiography combined with computerized densitometry revealed that in low-dose animals most of the radioactivity was confined to maternal liver and kidney, while at high doses more activity was observed in soft tissues and fluids, including amniotic fluid. In the embryo, the neuroepithelium showed the highest concentration, irrespective of dose and survival interval (30 min, 3 h, and 6 h). Upon administration of the high dose, up to five times more radioactivity (approximately 2,000 times more valproic acid) was recovered in embryonic tissues than after the low dose. It is concluded that high doses of VPA saturate the capacities of metabolism, excretion, and protein binding in the maternal organism, resulting in a higher proportion of the dose reaching the embryo, allowing more of the drug to be accumulated by the target organ, the neuroepithelium

  13. Oxygen-controlled automated neural differentiation of mouse embryonic stem cells.

    Science.gov (United States)

    Mondragon-Teran, Paul; Tostoes, Rui; Mason, Chris; Lye, Gary J; Veraitch, Farlan S

    2013-03-01

    Automation and oxygen tension control are two tools that provide significant improvements to the reproducibility and efficiency of stem cell production processes. the aim of this study was to establish a novel automation platform capable of controlling oxygen tension during both the cell-culture and liquid-handling steps of neural differentiation processes. We built a bespoke automation platform, which enclosed a liquid-handling platform in a sterile, oxygen-controlled environment. An airtight connection was used to transfer cell culture plates to and from an automated oxygen-controlled incubator. Our results demonstrate that our system yielded comparable cell numbers, viabilities, metabolism profiles and differentiation efficiencies when compared with traditional manual processes. Interestingly, eliminating exposure to ambient conditions during the liquid-handling stage resulted in significant improvements in the yield of MAP2-positive neural cells, indicating that this level of control can improve differentiation processes. This article describes, for the first time, an automation platform capable of maintaining oxygen tension control during both the cell-culture and liquid-handling stages of a 2D embryonic stem cell differentiation process.

  14. Overexpression of Cardiac-Specific Kinase TNNI3K Promotes Mouse Embryonic Stem Cells Differentiation into Cardiomyocytes.

    Science.gov (United States)

    Wang, Yin; Wang, Shi-Qiang; Wang, Li-Peng; Yao, Yu-Hong; Ma, Chun-Yan; Ding, Jin-Feng; Ye, Jue; Meng, Xian-Min; Li, Jian-Jun; Xu, Rui-Xia

    2017-01-01

    Backgroud/Aims: The biological function of cardiac troponin I-interacting kinase (TNNI3K), a cardiac-specific functional kinase, is largely unknown. We investigated the effect of human TNNI3K (hTNNI3K) on the differentiation of mouse embryonic stem cells (mESCs) into cardiomyocytes. First, the time-space expression of endogenous Tnni3k was detected by real-time polymerase chain reaction (PCR) and western blotting at 16 different time-points over a period of 28 days. Further, action potentials and calcium current with/without 5 µM nifedipine were measured by patch clamp for mESC-derived cardiomyocytes. HTNNI3K and mouse-derived siRNA were transfected into mESC using lentivirus vector to induce hTNNI3K overexpression and knock-down, respectively. The number of troponin-T (cTnT) positive cells was greater in the group with TNNI3K overexpression as compared to that in control group, while less such cells were detected in the mTnni3k knock-down group as evaluated on flow cytometry (FCM) and ImageXpress Micro system. After upregulation of connexin43, cardiac troponin-I (Ctni), Ctni, Gata4 were detected in mESCs with TNNI3K overexpression; however, overexpression of α-Actinin and Mlc2v was not detected. Interestingly, Ctnt, connexin40 and connexin45, the markers of ventricular, atrial, and pacemaker cells, respectively, were detected in by real-time PCR in TNNI3K overexpression group. our study indicated that TNNI3K overexpression promoted mESC differentiating into beating cardiomyocytes and induced up-regulating expression of cTnT by PKCε signal pathway, which suggested a modulation of TNNI3K activity as a potential therapeutic approach for ischemic cardiac disease. © 2017 The Author(s) Published by S. Karger AG, Basel.

  15. Connective tissue growth factor/CCN2-null mouse embryonic fibroblasts retain intact transforming growth factor-β responsiveness

    International Nuclear Information System (INIS)

    Mori, Yasuji; Hinchcliff, Monique; Wu, Minghua; Warner-Blankenship, Matthew; Lyons, Karen M.; Varga, John

    2008-01-01

    Background: The matricellular protein connective tissue growth factor (CCN2) has been implicated in pathological fibrosis, but its physiologic role remains elusive. In vitro, transforming growth factor-β (TGF-β) induces CCN2 expression in mesenchymal cells. Because CCN2 can enhance profibrotic responses elicited by TGF-β, it has been proposed that CCN2 functions as an essential downstream signaling mediator for TGF-β. To explore this notion, we characterized TGF-β-induced activation of fibroblasts from CCN2-null (CCN2 -/- ) mouse embryos. Methods: The regulation of CCN2 expression was examined in vivo in a model of fibrosis induced by bleomycin. Cellular TGF-β signal transduction and regulation of collagen gene expression were examined in CCN2 -/- MEFs by immunohistochemistry, Northern, Western and RT-PCR analysis, immunocytochemistry and transient transfection assays. Results: Bleomycin-induced skin fibrosis in the mouse was associated with substantial CCN2 up-regulation in lesional fibroblasts. Whereas in vitro proliferation rate of CCN2 -/- MEFs was markedly reduced compared to wild type MEFs, TGF-β-induced activation of the Smad pathways, including Smad2 phosphorylation, Smad2/3 and Smad4 nuclear accumulation and Smad-dependent transcriptional responses, were unaffected by loss of CCN2. The stimulation of COL1A2 and fibronectin mRNA expression and promoter activity, and of corresponding protein levels, showed comparable time and dose-response in wild type and CCN2 -/- MEFs, whereas stimulation of alpha smooth muscle actin and myofibroblast transdifferentiation showed subtle impairment in MEFs lacking CCN2. Conclusion: Whereas endogenous CCN2 plays a role in regulation of proliferation and TGF-β-induced myofibroblast transdifferentiation, it appears to be dispensable for Smad-dependent stimulation of collagen and extracellular matrix synthesis in murine embryonic fibroblasts

  16. Anticancer activity of biologically synthesized silver and gold nanoparticles on mouse myoblast cancer cells and their toxicity against embryonic zebrafish

    Energy Technology Data Exchange (ETDEWEB)

    Ramachandran, Rajan [Centre for Advanced Studies in Botany, School of Life Sciences, University of Madras, Guindy Campus, Chennai 600 025, Tamil Nadu (India); Krishnaraj, Chandran [Department of Food Science & Technology, College of Agriculture & Life Sciences, Chonbuk National University, Jeonju 561-756 (Korea, Republic of); M/s. Eureka Forbes Ltd, R & D Centre, Kudlu, Bangalore (India); Sivakumar, Allur Subramaniyan [Department of Animal Biotechnology, Chonbuk National University, Jeonju 54896 (Korea, Republic of); Prasannakumar, Palaniappan [Advanced Biomedical Imaging Center, Department of Electronic Engineering, Chonbuk National University, Jeonju 54896 (Korea, Republic of); Abhay Kumar, V.K. [M/s. Eureka Forbes Ltd, R & D Centre, Kudlu, Bangalore (India); Shim, Kwan Seob [Department of Animal Biotechnology, Chonbuk National University, Jeonju 54896 (Korea, Republic of); Song, Chul-Gyu [Advanced Biomedical Imaging Center, Department of Electronic Engineering, Chonbuk National University, Jeonju 54896 (Korea, Republic of); Yun, Soon-Il, E-mail: siyun@jbnu.ac.kr [Department of Food Science & Technology, College of Agriculture & Life Sciences, Chonbuk National University, Jeonju 561-756 (Korea, Republic of)

    2017-04-01

    The aim of this study was to evaluate the anticancer activity of bioinspired silver nanoparticles (AgNPs) and gold nanoparticles (AuNPs) against mouse myoblast cancer cells (C{sub 2}C{sub 12}). Both AgNPs and AuNPs were biologically synthesized using Spinacia oleracea Linn., aqueous leaves extract. UV–Vis. spectrophotometer, high resolution-transmission electron microscopy (HR-TEM), field emission-scanning electron microscopy (FE-SEM) and X-ray diffraction (XRD) studies supported the successful synthesis of AgNPs and AuNPs. Both these NPs have shown cytotoxicity against C{sub 2}C{sub 12} cells even at very low concentration (5 μg/mL). Acridine orange/Ethidium bromide (AO/EB) dual staining confirmed the apoptotic morphological features. The levels of caspase enzymes (caspase-3 and caspase-7) were significantly up-regulated in NPs treated myoblast cells than the plant extract. Furthermore, in zebrafish embryo toxicity study, AgNPs showed 100% mortality at 3 μg/mL concentration while AuNPs exhibited the same at much higher concentration (300 mg/mL). Taken together, these results provide a preliminary guidance for the development of biomaterials based drugs to fight against the fatal diseases for example cancer. - Highlights: • Anticancer activity was done for the first time against mouse myoblast cells. • AgNPs showed 100% growth inhibition against C{sub 2}C{sub 12} cells at 20 μg/mL concentration. • AO/EB dual staining and caspase assays confirmed the apoptotic features. • Nanoparticles treated embryos showed yolk sac edema and tail malformation. • AgNPs were found to be more toxic to embryonic zebrafishes than the AuNPs.

  17. Non-Serotonergic Neurotoxicity by MDMA (Ecstasy in Neurons Derived from Mouse P19 Embryonal Carcinoma Cells.

    Directory of Open Access Journals (Sweden)

    Dina Popova

    Full Text Available 3,4-methylenedioxymethamphetamine (MDMA; ecstasy is a commonly abused recreational drug that causes neurotoxic effects in both humans and animals. The mechanism behind MDMA-induced neurotoxicity is suggested to be species-dependent and needs to be further investigated on the cellular level. In this study, the effects of MDMA in neuronally differentiated P19 mouse embryonal carcinoma cells have been examined. MDMA produces a concentration-, time- and temperature-dependent toxicity in differentiated P19 neurons, as measured by intracellular MTT reduction and extracellular LDH activity assays. The P19-derived neurons express both the serotonin reuptake transporter (SERT, that is functionally active, and the serotonin metabolizing enzyme monoamine oxidase A (MAO-A. The involvement of these proteins in the MDMA-induced toxicity was investigated by a pharmacological approach. The MAO inhibitors clorgyline and deprenyl, and the SERT inhibitor fluoxetine, per se or in combination, were not able to mimic the toxic effects of MDMA in the P19-derived neurons or block the MDMA-induced cell toxicity. Oxidative stress has been implicated in MDMA-induced neurotoxicity, but pre-treatment with the antioxidants α-tocopherol or N-acetylcysteine did not reveal any protective effects in the P19 neurons. Involvement of mitochondria in the MDMA-induced cytotoxicity was also examined, but MDMA did not alter the mitochondrial membrane potential (ΔΨm in the P19 neurons. We conclude that MDMA produce a concentration-, time- and temperature-dependent neurotoxicity and our results suggest that the mechanism behind MDMA-induced toxicity in mouse-derived neurons do not involve the serotonergic system, oxidative stress or mitochondrial dysfunction.

  18. Non-Serotonergic Neurotoxicity by MDMA (Ecstasy) in Neurons Derived from Mouse P19 Embryonal Carcinoma Cells.

    Science.gov (United States)

    Popova, Dina; Forsblad, Andréas; Hashemian, Sanaz; Jacobsson, Stig O P

    2016-01-01

    3,4-methylenedioxymethamphetamine (MDMA; ecstasy) is a commonly abused recreational drug that causes neurotoxic effects in both humans and animals. The mechanism behind MDMA-induced neurotoxicity is suggested to be species-dependent and needs to be further investigated on the cellular level. In this study, the effects of MDMA in neuronally differentiated P19 mouse embryonal carcinoma cells have been examined. MDMA produces a concentration-, time- and temperature-dependent toxicity in differentiated P19 neurons, as measured by intracellular MTT reduction and extracellular LDH activity assays. The P19-derived neurons express both the serotonin reuptake transporter (SERT), that is functionally active, and the serotonin metabolizing enzyme monoamine oxidase A (MAO-A). The involvement of these proteins in the MDMA-induced toxicity was investigated by a pharmacological approach. The MAO inhibitors clorgyline and deprenyl, and the SERT inhibitor fluoxetine, per se or in combination, were not able to mimic the toxic effects of MDMA in the P19-derived neurons or block the MDMA-induced cell toxicity. Oxidative stress has been implicated in MDMA-induced neurotoxicity, but pre-treatment with the antioxidants α-tocopherol or N-acetylcysteine did not reveal any protective effects in the P19 neurons. Involvement of mitochondria in the MDMA-induced cytotoxicity was also examined, but MDMA did not alter the mitochondrial membrane potential (ΔΨm) in the P19 neurons. We conclude that MDMA produce a concentration-, time- and temperature-dependent neurotoxicity and our results suggest that the mechanism behind MDMA-induced toxicity in mouse-derived neurons do not involve the serotonergic system, oxidative stress or mitochondrial dysfunction.

  19. Anticancer activity of biologically synthesized silver and gold nanoparticles on mouse myoblast cancer cells and their toxicity against embryonic zebrafish

    International Nuclear Information System (INIS)

    Ramachandran, Rajan; Krishnaraj, Chandran; Sivakumar, Allur Subramaniyan; Prasannakumar, Palaniappan; Abhay Kumar, V.K.; Shim, Kwan Seob; Song, Chul-Gyu; Yun, Soon-Il

    2017-01-01

    The aim of this study was to evaluate the anticancer activity of bioinspired silver nanoparticles (AgNPs) and gold nanoparticles (AuNPs) against mouse myoblast cancer cells (C 2 C 12 ). Both AgNPs and AuNPs were biologically synthesized using Spinacia oleracea Linn., aqueous leaves extract. UV–Vis. spectrophotometer, high resolution-transmission electron microscopy (HR-TEM), field emission-scanning electron microscopy (FE-SEM) and X-ray diffraction (XRD) studies supported the successful synthesis of AgNPs and AuNPs. Both these NPs have shown cytotoxicity against C 2 C 12 cells even at very low concentration (5 μg/mL). Acridine orange/Ethidium bromide (AO/EB) dual staining confirmed the apoptotic morphological features. The levels of caspase enzymes (caspase-3 and caspase-7) were significantly up-regulated in NPs treated myoblast cells than the plant extract. Furthermore, in zebrafish embryo toxicity study, AgNPs showed 100% mortality at 3 μg/mL concentration while AuNPs exhibited the same at much higher concentration (300 mg/mL). Taken together, these results provide a preliminary guidance for the development of biomaterials based drugs to fight against the fatal diseases for example cancer. - Highlights: • Anticancer activity was done for the first time against mouse myoblast cells. • AgNPs showed 100% growth inhibition against C 2 C 12 cells at 20 μg/mL concentration. • AO/EB dual staining and caspase assays confirmed the apoptotic features. • Nanoparticles treated embryos showed yolk sac edema and tail malformation. • AgNPs were found to be more toxic to embryonic zebrafishes than the AuNPs.

  20. Generation of Aggregates of Mouse Embryonic Stem Cells that Show Symmetry Breaking, Polarization and Emergent Collective Behaviour In Vitro.

    Science.gov (United States)

    Baillie-Johnson, Peter; van den Brink, Susanne Carina; Balayo, Tina; Turner, David Andrew; Martinez Arias, Alfonso

    2015-11-24

    We have developed a protocol improving current Embryoid Body (EB) culture which allows the study of self-organization, symmetry breaking, axial elongation and cell fate specification using aggregates of mouse embryonic stem cells (mESCs) in suspension culture. Small numbers of mESCs are aggregated in basal medium for 48 hr in non-tissue-culture-treated, U-bottomed 96-well plates, after which they are competent to respond to experimental signals. Following treatment, these aggregates begin to show signs of polarized gene expression and gradually alter their morphology from a spherical mass of cells to an elongated, well organized structure in the absence of external asymmetry cues. These structures are not only able to display markers of the three germ layers, but actively display gastrulation-like movements, evidenced by a directional dislodgement of individual cells from the aggregate, which crucially occurs at one region of the elongated structure. This protocol provides a detailed method for the reproducible formation of these aggregates, their stimulation with signals such as Wnt/β-Catenin activation and BMP inhibition and their analysis by single time-point or time-lapse fluorescent microscopy. In addition, we describe modifications to current whole-mount mouse embryo staining procedures for immunocytochemical analysis of specific markers within fixed aggregates. The changes in morphology, gene expression and length of the aggregates can be quantitatively measured, providing information on how signals can alter axial fates. It is envisaged that this system can be applied both to the study of early developmental events such as axial development and organization, and more broadly, the processes of self-organization and cellular decision-making. It may also provide a suitable niche for the generation of cell types present in the embryo that are unobtainable from conventional adherent culture such as spinal cord and motor neurones.

  1. De novo CNV formation in mouse embryonic stem cells occurs in the absence of Xrcc4-dependent nonhomologous end joining.

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    Martin F Arlt

    2012-09-01

    Full Text Available Spontaneous copy number variant (CNV mutations are an important factor in genomic structural variation, genomic disorders, and cancer. A major class of CNVs, termed nonrecurrent CNVs, is thought to arise by nonhomologous DNA repair mechanisms due to the presence of short microhomologies, blunt ends, or short insertions at junctions of normal and de novo pathogenic CNVs, features recapitulated in experimental systems in which CNVs are induced by exogenous replication stress. To test whether the canonical nonhomologous end joining (NHEJ pathway of double-strand break (DSB repair is involved in the formation of this class of CNVs, chromosome integrity was monitored in NHEJ-deficient Xrcc4(-/- mouse embryonic stem (ES cells following treatment with low doses of aphidicolin, a DNA replicative polymerase inhibitor. Mouse ES cells exhibited replication stress-induced CNV formation in the same manner as human fibroblasts, including the existence of syntenic hotspot regions, such as in the Auts2 and Wwox loci. The frequency and location of spontaneous and aphidicolin-induced CNV formation were not altered by loss of Xrcc4, as would be expected if canonical NHEJ were the predominant pathway of CNV formation. Moreover, de novo CNV junctions displayed a typical pattern of microhomology and blunt end use that did not change in the absence of Xrcc4. A number of complex CNVs were detected in both wild-type and Xrcc4(-/- cells, including an example of a catastrophic, chromothripsis event. These results establish that nonrecurrent CNVs can be, and frequently are, formed by mechanisms other than Xrcc4-dependent NHEJ.

  2. The perfect host: a mouse host embryo facilitating more efficient germ line transmission of genetically modified embryonic stem cells.

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    Robert A Taft

    Full Text Available There is a continual need to improve efficiency in creating precise genetic modifications in mice using embryonic stem cells (ESCs. We describe a novel approach resulting in 100% germline transmission from competent injected ESCs. We developed an F1 mouse host embryo (Perfect Host, PH that selectively ablates its own germ cells via tissue-specific induction of diphtheria toxin. This approach allows competent microinjected ESCs to fully dominate the germline, eliminating competition for this critical niche in the developing and adult animal. This is in contrast to conventional methods, where competition from host germ cells results in offspring derived from host cells and ESCs, necessitating extensive breeding of chimeras and genotyping to identify germline. The germline transmission process is also complicated by variability in the actual number of ESCs that colonize the germline niche and the proportion that are germline competent. To validate the PH approach we used ESC lines derived from 129 F1, BALB/cByJ, and BTBR backgrounds as well as an iPS line. Resulting chimeric males produced 194 offspring, all paternally derived from the introduced stem cells, with no offspring being derived from the host genome. We further tested this approach using eleven genetically modified C57BL/6N ESC lines (International Knockout Mouse Consortium. ESC germline transmission was observed in 9/11 (82% lines using PH blastocysts, compared to 6/11 (55% when conventional host blastocysts were used. Furthermore, less than 35% (83/240 of mice born in the first litters from conventional chimeras were confirmed to be of ESC-origin. By comparison, 100% (137/137 of the first litter offspring of PH chimeras were confirmed as ESC-derived. Together, these data demonstrate that the PH approach increases the probability of germline transmission and speeds the generation of ESC derived animals from chimeras. Collectively, this approach reduces the time and costs inherent in the

  3. Meta-analysis of differentiating mouse embryonic stem cell gene expression kinetics reveals early change of a small gene set.

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    Clive H Glover

    2006-11-01

    Full Text Available Stem cell differentiation involves critical changes in gene expression. Identification of these should provide endpoints useful for optimizing stem cell propagation as well as potential clues about mechanisms governing stem cell maintenance. Here we describe the results of a new meta-analysis methodology applied to multiple gene expression datasets from three mouse embryonic stem cell (ESC lines obtained at specific time points during the course of their differentiation into various lineages. We developed methods to identify genes with expression changes that correlated with the altered frequency of functionally defined, undifferentiated ESC in culture. In each dataset, we computed a novel statistical confidence measure for every gene which captured the certainty that a particular gene exhibited an expression pattern of interest within that dataset. This permitted a joint analysis of the datasets, despite the different experimental designs. Using a ranking scheme that favored genes exhibiting patterns of interest, we focused on the top 88 genes whose expression was consistently changed when ESC were induced to differentiate. Seven of these (103728_at, 8430410A17Rik, Klf2, Nr0b1, Sox2, Tcl1, and Zfp42 showed a rapid decrease in expression concurrent with a decrease in frequency of undifferentiated cells and remained predictive when evaluated in additional maintenance and differentiating protocols. Through a novel meta-analysis, this study identifies a small set of genes whose expression is useful for identifying changes in stem cell frequencies in cultures of mouse ESC. The methods and findings have broader applicability to understanding the regulation of self-renewal of other stem cell types.

  4. Chromosomal instability in mouse embryonic fibroblasts null for the transcriptional co-repressor Ski.

    Science.gov (United States)

    Marcelain, Katherine; Armisen, Ricardo; Aguirre, Adam; Ueki, Nobuhide; Toro, Jessica; Colmenares, Clemencia; Hayman, Michael J

    2012-01-01

    Ski is a transcriptional regulator that has been considered an oncoprotein given its ability to induce oncogenic transformation in avian model systems. However, studies in mouse and in some human tumor cells have also indicated a tumor suppressor activity for this protein. We found that Ski-/- mouse embryo fibroblasts exhibit high levels of genome instability, namely aneuploidy, consistent with a tumor suppressor function for Ski. Time-lapse microscopy revealed lagging chromosomes and chromatin/chromosome bridges as the major cause of micronuclei (MN) formation and the subsequent aneuploidy. Although these cells arrested in mitosis after treatment with spindle disrupting drugs and exhibited a delayed metaphase/anaphase transition, spindle assembly checkpoint (SAC) was not sufficient to prevent chromosome missegregation, consistent with a weakened SAC. Our in vivo analysis also showed dynamic metaphase plate rearrangements with switches in polarity in cells arrested in metaphase. Importantly, after ectopic expression of Ski the cells that displayed this metaphase arrest died directly during metaphase or after aberrant cell division, relating SAC activation and mitotic cell death. This increased susceptibility to undergo mitosis-associated cell death reduced the number of MN-containing cells. The presented data support a new role for Ski in the mitotic process and in maintenance of genetic stability, providing insights into the mechanism of tumor suppression mediated by this protein. Copyright © 2011 Wiley Periodicals, Inc.

  5. Human amniotic epithelial cell feeder layers maintain mouse embryonic stem cell pluripotency via epigenetic regulation of the c-Myc promoter.

    Science.gov (United States)

    Liu, Te; Cheng, Weiwei; Liu, Tianjin; Guo, Lihe; Huang, Qin; Jiang, Lizhen; Du, Xiling; Xu, Fuhui; Liu, Zhixue; Lai, Dongmei

    2010-02-01

    Mouse embryonic stem cells (ESCs) are typically cultured on a feeder layer of mouse embryonic fibroblasts (MEFs), with leukemia inhibitory factor (LIF) added to maintain them in an undifferentiated state. We have previously shown that human amniotic epithelial cells (hAECs) can be used as feeder cells to maintain mouse ESC pluripotency, but the mechanism for this is unknown. In the present study, we found that CpG islands 5' of the c-Myc gene remain hypomethylated in mouse ESCs cultured on hAECs. In addition, levels of acetylation of histone H3 and trimethylation of histone H3K4 in the c-Myc gene promoter were higher in ES cells cultured on hAECs than those in ES cells cultured on MEFs. These data suggested that hAECs can alter mouse ESC gene expression via epigenetic modification of c-Myc, providing a possible mechanism for the hAEC-induced maintenance of ESCs in an undifferentiated state.

  6. FRS2α is Essential for the Fibroblast Growth Factor to Regulate the mTOR Pathway and Autophagy in Mouse Embryonic Fibroblasts

    OpenAIRE

    Xiang Lin, Yongyou Zhang, Leyuan Liu, Wallace L. McKeehan, Yuemao Shen, Siyang Song, Fen Wang

    2011-01-01

    Although the fibroblast growth factor (FGF) signaling axis plays important roles in cell survival, proliferation, and differentiation, the molecular mechanism underlying how the FGF elicits these diverse regulatory signals is not well understood. By using the Frs2α null mouse embryonic fibroblast (MEF) in conjunction with inhibitors to multiple signaling pathways, here we report that the FGF signaling axis activates mTOR via the FGF receptor substrate 2α (FRS2α)-mediated PI3K/A...

  7. Quantitative Proteomic Analysis of Mouse Embryonic Fibroblasts and Induced Pluripotent Stem Cells Using 16O /18O labeling

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Xin; Tian, Changhai; Liu, Miao; Wang, Yongxiang; Tolmachev, Aleksey V.; Sharma, Seema; Yu, Fang; Fu, Kai; Zheng, Jialin; Ding, Shi-Jian

    2012-04-06

    Induced pluripotent stem cells (iPSC) hold great promise for regenerative medicine as well as for investigations into the pathogenesis and treatment of various diseases. Understanding of key intracellular signaling pathways and protein targets that control development of iPSC from somatic cells is essential for designing new approaches to improve reprogramming efficiency. Here we report the development and application of an integrated quantitative proteomics platform for investigating differences in protein expressions between mouse embryonic fibroblasts (MEF) and MEF-derived iPSC. This platform consists of 16O/18O labeling, multidimensional peptide separation coupled with tandem mass spectrometry, and data analysis with UNiquant software. Using this platform a total of 2,481 proteins were identified and quantified from the 16O/18O-labeled MEF-iPSC proteome mixtures with a false discovery rate of 0.01. Among them, 218 proteins were significantly upregulated, while 247 proteins were significantly downregulated in iPSC compared to MEF. Many nuclear proteins, including Hdac1, Dnmt1, Pcna, Ccnd1, Smarcc1, and subunits in DNA replication and RNA polymerase II complex were found to be enhanced in iPSC. Protein network analysis revealed that Pcna functions as a hub orchestrating complicated mechanisms including DNA replication, epigenetic inheritance (Dnmt1) and chromatin remodeling (Smarcc1) to reprogram MEF and maintain stemness of iPSC.

  8. DNA polymerases beta and lambda mediate overlapping and independent roles in base excision repair in mouse embryonic fibroblasts.

    Directory of Open Access Journals (Sweden)

    Elena K Braithwaite

    2010-08-01

    Full Text Available Base excision repair (BER is a DNA repair pathway designed to correct small base lesions in genomic DNA. While DNA polymerase beta (pol beta is known to be the main polymerase in the BER pathway, various studies have implicated other DNA polymerases in back-up roles. One such polymerase, DNA polymerase lambda (pol lambda, was shown to be important in BER of oxidative DNA damage. To further explore roles of the X-family DNA polymerases lambda and beta in BER, we prepared a mouse embryonic fibroblast cell line with deletions in the genes for both pol beta and pol lambda. Neutral red viability assays demonstrated that pol lambda and pol beta double null cells were hypersensitive to alkylating and oxidizing DNA damaging agents. In vitro BER assays revealed a modest contribution of pol lambda to single-nucleotide BER of base lesions. Additionally, using co-immunoprecipitation experiments with purified enzymes and whole cell extracts, we found that both pol lambda and pol beta interact with the upstream DNA glycosylases for repair of alkylated and oxidized DNA bases. Such interactions could be important in coordinating roles of these polymerases during BER.

  9. A Novel Atypical PKC-Iota Inhibitor, Echinochrome A, Enhances Cardiomyocyte Differentiation from Mouse Embryonic Stem Cells.

    Science.gov (United States)

    Kim, Hyoung Kyu; Cho, Sung Woo; Heo, Hye Jin; Jeong, Seung Hun; Kim, Min; Ko, Kyung Soo; Rhee, Byoung Doo; Mishchenko, Natalia P; Vasileva, Elena A; Fedoreyev, Sergey A; Stonik, Valentin A; Han, Jin

    2018-06-02

    Echinochrome A (EchA) is a marine bioproduct extracted from sea urchins having antioxidant, antimicrobial, anti-inflammatory, and chelating effects, and is the active component of the clinical drug histochrome. We investigated the potential use of Ech A for inducing cardiomyocyte differentiation from mouse embryonic stem cells (mESCs). We also assessed the effects of Ech A on mitochondrial mass, inner membrane potential (Δψm), reactive oxygen species generation, and levels of Ca 2+ . To identify the direct target of Ech A, we performed in vitro kinase activity and surface plasmon resonance binding assays. Ech A dose-dependently enhanced cardiomyocyte differentiation with higher beating rates. Ech A (50 μM) increased the mitochondrial mass and membrane potential but did not alter the mitochondrial superoxide and Ca 2+ levels. The in vitro kinase activity of the atypical protein kinase C-iota (PKCι) was significantly decreased by 50 μM of Ech A with an IC 50 for PKCι activity of 107 μM. Computational protein-ligand docking simulation results suggested the direct binding of Ech A to PKCι, and surface plasmon resonance confirmed the direct binding with a low K D of 6.3 nM. Therefore, Ech A is a potential drug for enhancing cardiomyocyte differentiation from mESCs through direct binding to PKCι and inhibition of its activity.

  10. Mutagenicity of ultraviolet A radiation in the lacI transgene in Big Blue mouse embryonic fibroblasts

    International Nuclear Information System (INIS)

    Kim, Sang-in; Pfeifer, Gerd P.; Besaratinia, Ahmad

    2007-01-01

    Sunlight ultraviolet A (UVA) irradiation has been implicated in the etiology of human skin cancer. A genotoxic mode of action for UVA radiation has been suggested that involves photosensitization reactions giving rise to promutagenic DNA lesions. We investigated the mutagenicity of UVA in the lacI transgene in Big Blue mouse embryonic fibroblasts. UVA irradiation of these cells at a physiologically relevant dose of 18 J/cm 2 caused a 2.8-fold increase in the lacI mutant frequency relative to control, i.e., 12.12 ± 1.84 versus 4.39 ± 1.99 x 10 -5 (mean ± S.D.). DNA sequencing analysis showed that of 100 UVA-induced mutant plaques and 54 spontaneously arisen control plaques, 97 and 51, respectively, contained a minimum of one mutation along the lacI transgene. The vast majority of both induced- and spontaneous mutations were single base substitutions, although less frequently, there were also single and multiple base deletions and insertions, and tandem base substitutions. Detailed mutation spectrometry analysis revealed that G:C → T:A transversions, the signature mutations of oxidative DNA damage, were significantly induced by UVA irradiation (P -5 ; P < 0.00001). These findings are in complete agreement with those previously observed in the cII transgene of the same model system, and reaffirm the notion that intracellular photosensitization reactions causing promutagenic oxidative DNA damage are involved in UVA genotoxicity

  11. Mobile phone signal exposure triggers a hormesis-like effect in Atm+/+ and Atm-/- mouse embryonic fibroblasts.

    Science.gov (United States)

    Sun, Chuan; Wei, Xiaoxia; Fei, Yue; Su, Liling; Zhao, Xinyuan; Chen, Guangdi; Xu, Zhengping

    2016-11-18

    Radiofrequency electromagnetic fields (RF-EMFs) have been classified by the International Agency for Research on Cancer as possible carcinogens to humans; however, this conclusion is based on limited epidemiological findings and lacks solid support from experimental studies. In particular, there are no consistent data regarding the genotoxicity of RF-EMFs. Ataxia telangiectasia mutated (ATM) is recognised as a chief guardian of genomic stability. To address the debate on whether RF-EMFs are genotoxic, we compared the effects of 1,800 MHz RF-EMF exposure on genomic DNA in mouse embryonic fibroblasts (MEFs) with proficient (Atm +/+ ) or deficient (Atm -/- ) ATM. In Atm +/+ MEFs, RF-EMF exposure for 1 h at an average special absorption rate of 4.0 W/kg induced significant DNA single-strand breaks (SSBs) and activated the SSB repair mechanism. This effect reduced the DNA damage to less than that of the background level after 36 hours of exposure. In the Atm -/- MEFs, the same RF-EMF exposure for 12 h induced both SSBs and double-strand breaks and activated the two repair processes, which also reduced the DNA damage to less than the control level after prolonged exposure. The observed phenomenon is similar to the hormesis of a toxic substance at a low dose. To the best of our knowledge, this study is the first to report a hormesis-like effect of an RF-EMF.

  12. Survival of partially differentiated mouse embryonic stem cells in the scala media of the guinea pig cochlea.

    Science.gov (United States)

    Hildebrand, Michael S; Dahl, Hans-Henrik M; Hardman, Jennifer; Coleman, Bryony; Shepherd, Robert K; de Silva, Michelle G

    2005-12-01

    The low regenerative capacity of the hair cells of the mammalian inner ear is a major obstacle for functional recovery following sensorineural hearing loss. A potential treatment is to replace damaged tissue by transplantation of stem cells. To test this approach, undifferentiated and partially differentiated mouse embryonic stem (ES) cells were delivered into the scala media of the deafened guinea pig cochlea. Transplanted cells survived in the scala media for a postoperative period of at least nine weeks, evidenced by histochemical and direct fluorescent detection of enhanced green fluorescent protein (EGFP). Transplanted cells were discovered near the spiral ligament and stria vascularis in the endolymph fluid of the scala media. In some cases, cells were observed close to the damaged organ of Corti structure. There was no evidence of significant immunological rejection of the implanted ES cells despite the absence of immunosuppression. Our surgical approach allowed efficient delivery of ES cells to the scala media while preserving the delicate structures of the cochlea. This is the first report of the survival of partially differentiated ES cells in the scala media of the mammalian cochlea, and it provides support for the potential of cell-based therapies for sensorineural hearing impairment.

  13. Reverse engineering a mouse embryonic stem cell-specific transcriptional network reveals a new modulator of neuronal differentiation.

    Science.gov (United States)

    De Cegli, Rossella; Iacobacci, Simona; Flore, Gemma; Gambardella, Gennaro; Mao, Lei; Cutillo, Luisa; Lauria, Mario; Klose, Joachim; Illingworth, Elizabeth; Banfi, Sandro; di Bernardo, Diego

    2013-01-01

    Gene expression profiles can be used to infer previously unknown transcriptional regulatory interaction among thousands of genes, via systems biology 'reverse engineering' approaches. We 'reverse engineered' an embryonic stem (ES)-specific transcriptional network from 171 gene expression profiles, measured in ES cells, to identify master regulators of gene expression ('hubs'). We discovered that E130012A19Rik (E13), highly expressed in mouse ES cells as compared with differentiated cells, was a central 'hub' of the network. We demonstrated that E13 is a protein-coding gene implicated in regulating the commitment towards the different neuronal subtypes and glia cells. The overexpression and knock-down of E13 in ES cell lines, undergoing differentiation into neurons and glia cells, caused a strong up-regulation of the glutamatergic neurons marker Vglut2 and a strong down-regulation of the GABAergic neurons marker GAD65 and of the radial glia marker Blbp. We confirmed E13 expression in the cerebral cortex of adult mice and during development. By immuno-based affinity purification, we characterized protein partners of E13, involved in the Polycomb complex. Our results suggest a role of E13 in regulating the division between glutamatergic projection neurons and GABAergic interneurons and glia cells possibly by epigenetic-mediated transcriptional regulation.

  14. UV light induces premature senescence in Akt1-null mouse embryonic fibroblasts by increasing intracellular levels of ROS

    International Nuclear Information System (INIS)

    Jee, Hye Jin; Kim, Hyun-Ju; Kim, Ae Jeong; Bae, Yoe-Sik; Bae, Sun Sik; Yun, Jeanho

    2009-01-01

    Akt/PKB plays a pivotal role in cell survival and proliferation. Previously, we reported that UV-irradiation induces extensive cell death in Akt2 -/- mouse embryonic fibroblasts (MEFs) while Akt1 -/- MEFs show cell cycle arrest. Here, we find that Akt1 -/- MEFs exhibit phenotypic changes characteristics of senescence upon UV-irradiation. An enlarged and flattened morphology, a reduced cell proliferation and an increased senescence-associated β-galactosidase (SA β-gal) staining indicate that Akt1 -/- MEFs undergo premature senescence after UV-irradiation. Restoring Akt1 expression in Akt1 -/- MEFs suppressed SA β-gal activity, indicating that UV-induced senescence is due to the absence of Akt1 function. Notably, levels of ROS were rapidly increased upon UV-irradiation and the ROS scavenger NAC inhibits UV-induced senescence of Akt1 -/- MEFs, suggesting that UV light induces premature senescence in Akt1 -/- MEFs by modulating intracellular levels of ROS. In conjunction with our previous work, this indicates that different isoforms of Akt have distinct function in response to UV-irradiation.

  15. Rp58 and p27kip1 coordinate cell cycle exit and neuronal migration within the embryonic mouse cerebral cortex.

    Science.gov (United States)

    Clément, Olivier; Hemming, Isabel Anne; Gladwyn-Ng, Ivan Enghian; Qu, Zhengdong; Li, Shan Shan; Piper, Michael; Heng, Julian Ik-Tsen

    2017-05-15

    During the development of the mammalian cerebral cortex, newborn postmitotic projection neurons are born from local neural stem cells and must undergo radial migration so as to position themselves appropriately to form functional neural circuits. The zinc finger transcriptional repressor Rp58 (also known as Znf238 or Zbtb18) is critical for coordinating corticogenesis, but its underlying molecular mechanism remains to be better characterised. Here, we demonstrate that the co-expression of Rp58 and the cyclin dependent kinase inhibitor (CDKI) p27 kip1 is important for E14.5-born cortical neurons to coordinate cell cycle exit and initiate their radial migration. Notably, we find that the impaired radial positioning of Rp58-deficient cortical neurons within the embryonic (E17.5) mouse cortex, as well as their multipolar to bipolar transition from the intermediate zone to the cortical plate can be restored by forced expression of p27 kip1 in concert with suppression of Rnd2, a downstream target gene of Rp58. Furthermore, the restorative effects of p27 kip1 and Rnd2 abrogation are reminiscent of suppressing RhoA signalling in Rp58-deficient cells. Our findings demonstrate functional interplay between a transcriptional regulator and a CDKI to mediate neuroprogenitor cell cycle exit, as well as to promote radial migration through a molecular mechanism consistent with suppression of RhoA signalling.

  16. Ultrastructural characteristics of three undifferentiated mouse embryonic stem cell lines and their differentiated three-dimensional derivatives: a comparative study.

    Science.gov (United States)

    Alharbi, Suzan; Elsafadi, Mona; Mobarak, Mohammed; Alrwili, Ali; Vishnubalaji, Radhakrishnan; Manikandan, Muthurangan; Al-Qudsi, Fatma; Karim, Saleh; Al-Nabaheen, May; Aldahmash, Abdullah; Mahmood, Amer

    2014-04-01

    The fine structures of mouse embryonic stem cells (mESCs) grown as colonies and differentiated in three-dimensional (3D) culture as embryoid bodies (EBs) were analyzed by transmission electron microscopy. Undifferentiated mESCs expressed markers that proved their pluripotency. Differentiated EBs expressed different differentiation marker proteins from the three germ layers. The ultrastructure of mESCs revealed the presence of microvilli on the cell surfaces, large and deep infolded nuclei, low cytoplasm-to-nuclear ratios, frequent lipid droplets, nonprominent Golgi apparatus, and smooth endoplasmic reticulum. In addition, we found prominent juvenile mitochondria and free ribosomes-rich cytoplasm in mESCs. Ultrastructure of the differentiated mESCs as EBs showed different cell arrangements, which indicate the different stages of EB development and differentiation. The morphologies of BALB/c and 129 W9.5 EBs were very similar at day 4, whereas C57BL/6 EBs were distinct from the others at day 4. This finding suggested that differentiation of EBs from different cell lines occurs in the same pattern but not at the same rate. Conversely, the ultrastructure results of BALB/c and 129 W9.5 ESCs revealed differentiating features, such as the dilated profile of a rough endoplasmic reticulum. In addition, we found low expression levels of undifferentiated markers on the outer cells of BALB/c and 129 W9.5 mESC colonies, which suggests a faster differentiation potential.

  17. Phospholipase C-related catalytically inactive protein participates in the autophagic elimination of Staphylococcus aureus infecting mouse embryonic fibroblasts.

    Directory of Open Access Journals (Sweden)

    Kae Harada-Hada

    Full Text Available Autophagy is an intrinsic host defense system that recognizes and eliminates invading bacterial pathogens. We have identified microtubule-associated protein 1 light chain 3 (LC3, a hallmark of autophagy, as a binding partner of phospholipase C-related catalytically inactive protein (PRIP that was originally identified as an inositol trisphosphate-binding protein. Here, we investigated the involvement of PRIP in the autophagic elimination of Staphylococcus aureus in infected mouse embryonic fibroblasts (MEFs. We observed significantly more LC3-positive autophagosome-like vacuoles enclosing an increased number of S. aureus cells in PRIP-deficient MEFs than control MEFs, 3 h and 4.5 h post infection, suggesting that S. aureus proliferates in LC3-positive autophagosome-like vacuoles in PRIP-deficient MEFs. We performed autophagic flux analysis using an mRFP-GFP-tagged LC3 plasmid and found that autophagosome maturation is significantly inhibited in PRIP-deficient MEFs. Furthermore, acidification of autophagosomes was significantly inhibited in PRIP-deficient MEFs compared to the wild-type MEFs, as determined by LysoTracker staining and time-lapse image analysis performed using mRFP-GFP-tagged LC3. Taken together, our data show that PRIP is required for the fusion of S. aureus-containing autophagosome-like vacuoles with lysosomes, indicating that PRIP is a novel modulator in the regulation of the innate immune system in non-professional phagocytic host cells.

  18. Inhibition of proliferation and differentiation and promotion of apoptosis by cyclin L2 in mouse embryonic carcinoma P19 cells

    International Nuclear Information System (INIS)

    Zhuo, Lili; Gong, Jie; Yang, Rong; Sheng, Yanhui; Zhou, Lei; Kong, Xiangqing; Cao, Kejiang

    2009-01-01

    Cyclin L2 (CCNL2) is a novel member of the cyclin gene family. In a previous study, we demonstrated that CCNL2 expression was upregulated in ventricular septum tissues from patients with ventricular septal defect compared to healthy controls. In the present study, we established a stable CCNL2-overexpressing P19 cell line that can differentiate to myocardial cells when treated with 1% dimethyl sulfoxide (DMSO). Our data showed that stable CCNL2-overexpressing P19 cells were less differentiated after treatment with 1% DMSO and that expression of myocardial cell differentiation-related genes (such as cardiac actin, GATA4, Mef2C, Nkx2.5, and BNP) were reduced compared to vector-only transfected P19. Moreover, P19 cells overexpressing the CCNL2 gene had a reduced growth rate and a remarkably decreased S phase. We also found that these cells underwent apoptosis, as detected by two different apoptosis assays. The anti-apoptotic Bcl-2 protein was also downregulated in these cells. In addition, real-time PCR analysis revealed that expression of Wnt and β-catenin was suppressed and GSK3β was induced in the CCNL2-overexpressing P19 cells. These data suggest that overexpression of CCNL2 inhibited proliferation and differentiation of mouse embryonic carcinoma P19 cells and induced them to undergo apoptosis, possibly through the Wnt signal transduction pathway.

  19. Yap1 is dispensable for self-renewal but required for proper differentiation of mouse embryonic stem (ES) cells.

    Science.gov (United States)

    Chung, HaeWon; Lee, Bum-Kyu; Uprety, Nadima; Shen, Wenwen; Lee, Jiwoon; Kim, Jonghwan

    2016-04-01

    Yap1 is a transcriptional co-activator of the Hippo pathway. The importance of Yap1 in early cell fate decision during embryogenesis has been well established, though its role in embryonic stem (ES) cells remains elusive. Here, we report that Yap1 plays crucial roles in normal differentiation rather than self-renewal of ES cells. Yap1-depleted ES cells maintain undifferentiated state with a typical colony morphology as well as robust alkaline phosphatase activity. These cells also retain comparable levels of the core pluripotent factors, such as Pou5f1 and Sox2, to the levels in wild-type ES cells without significant alteration of lineage-specific marker genes. Conversely, overexpression of Yap1 in ES cells promotes nuclear translocation of Yap1, resulting in disruption of self-renewal and triggering differentiation by up-regulating lineage-specific genes. Moreover, Yap1-deficient ES cells show impaired induction of lineage markers during differentiation. Collectively, our data demonstrate that Yap1 is a required factor for proper differentiation of mouse ES cells, while remaining dispensable for self-renewal. © 2016 The Authors.

  20. Live dynamic analysis of mouse embryonic cardiogenesis with functional optical coherence tomography

    Science.gov (United States)

    Lopez, Andrew L.; Wang, Shang; Larina, Irina V.

    2018-02-01

    Hemodynamic load, contractile forces, and tissue elasticity are regulators of cardiac development and contribute to the mechanical homeostasis of the developing vertebrate heart. Congenital heart disease (CHD) is a prevalent condition in the United States that affects 8 in 1000 live births[1], and has been linked to disrupted cardiac biomechanics[2-4]. Therefore, it is important to understand how these forces integrate and regulate vertebrate cardiac development to inform clinical strategies to treat CHD early on by reintroducing proper mechanical load or modulating downstream factors that rely on mechanical signalling. Toward investigation of biomechanical regulation of mammalian cardiovascular dynamics and development, our methodology combines live mouse embryo culture protocols, state-of-the-art structural and functional Optical Coherence Tomography (OCT), second harmonic generation (SHG) microscopy, and computational analysis. Using these approaches, we assess functional aspects of the developing heart and characterize how they coincide with a determinant of tissue stiffness and main constituent of the extracellular matrix (ECM)—type I collagen. This work is bringing us closer to understanding how cardiac biomechanics change temporally and spatially during normal development, and how it regulates ECM to maintain mechanical homeostasis for proper function.

  1. The building of the neocortex with non-hyperpolarizing neurotransmitters.

    Science.gov (United States)

    Ascenzi, Matteo; Bony, Guillaume

    2017-09-01

    The development of the neocortex requires the synergic action of several secreted molecules to achieve the right amount of proliferation, differentiation, and migration of neural cells. Neurons are well known to release neurotransmitters (NTs) in adult and a growing body of evidences describes the presence of NTs already in the embryonic brain, long before the generation of synapses. NTs are classified as inhibitory or excitatory based on the physiological responses of the target neuron. However, this view is challenged by the fact that glycine and GABA NTs are excitatory during development. Many reviews have described the role of nonhyperpolarizing GABA at this stage. Nevertheless, a global consideration of the inhibitory neurotransmitters and their downstream signaling during the embryonic cortical development is still needed. For example, taurine, the most abundant neurotransmitter during development is poorly studied regarding its role during cortical development. In the light of recent discoveries, we will discuss the functions of glycine, GABA, and taurine during embryonic cortical development with an emphasis on their downstream signaling. © 2017 Wiley Periodicals, Inc. Develop Neurobiol 77: 1023-1037, 2017. © 2017 Wiley Periodicals, Inc.

  2. Effect of culture medium volume and embryo density on early mouse embryonic development: tracking the development of the individual embryo.

    Science.gov (United States)

    Dai, Shan-Jun; Xu, Chang-Long; Wang, Jeffrey; Sun, Ying-Pu; Chian, Ri-Cheng

    2012-07-01

    To determine the optimal volume or density of embryos for the well-of-the-well (WOW) system in order to track the development of individual embryos and to determine whether the WOW system can reverse the negative impact of culturing embryos singly. (1) Mouse embryos (groups of nine at the 2-cell stage) were cultured in 6.25 μl, 12.50 μl, 25.00 μl and 50.00 μl of droplets of culture medium under paraffin oil; (2) Groups of three, six, nine and twelve embryos at the 2-cell stage were cultured in 50 μl of droplet of culture medium under paraffin oil; (3) Groups of nine embryos at the 2-cell stage were cultured in 50 μl of droplet under paraffin oil with or without nine micro-wells made on the bottom of the Petri dish into each of which were placed one of the nine embryos (WOW system). Also single 2-cell stage embryos was cultured individually in 5.5 μl of droplet of culture medium under paraffin oil with or without a single micro-well made on the bottom of the Petri dish (WOW system for single culture). At the end of culture, the percentages of blastocyst development, hatching and hatched blastocysts were compared in each group. The blastocysts were fixed for differential staining. The blastocyst development was significantly higher (P WOW system. The blastocyst development was not improved when single embryo cultured individually in a micro-well was compared to single embryo cultured individually without micro-well. The total cell numbers of blastocysts were significantly higher in group embryo culture than single embryo culture regardless of whether the WOW system was used. In addition, the total cell numbers of blastocysts were significantly higher (P WOW system than without. Group embryo culture is superior to single embryo culture for blastocyst development. The WOW system with 50 μl of droplet of culture medium can be used to track the individual development of embryo cultured in groups while preserving good embryonic development. The reduced

  3. MicroRNA-33 promotes the replicative senescence of mouse embryonic fibroblasts by suppressing CDK6

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Shun; Huang, Haijiao; Li, Nanhong; Zhang, Bing; Jia, Yubin; Yang, Yukun; Yuan, Yuan; Xiong, Xing-dong; Wang, Dengchuan; Zheng, Hui-ling [Institute of Aging Research, Guangdong Medical University, Dongguan (China); Guangdong Provincial Key Laboratory of Medical Molecular Diagnostics, Dongguan (China); Institute of Biochemistry & Molecular Biology, Guangdong Medical University, Zhanjiang (China); Liu, Xinguang, E-mail: xgliu64@126.com [Institute of Aging Research, Guangdong Medical University, Dongguan (China); Guangdong Provincial Key Laboratory of Medical Molecular Diagnostics, Dongguan (China); Institute of Biochemistry & Molecular Biology, Guangdong Medical University, Zhanjiang (China)

    2016-05-13

    MicroRNAs are a large class of tiny noncoding RNAs, which have emerged as critical regulators of gene expression, and thus are involved in multiple cellular processes, including cellular senescence. MicroRNA-33 has previously been established to exert crucial effect on cell proliferation, lipid metabolism and cholesterol metabolism. Nonetheless, the association between microRNA-33 and cellular senescence and its underlying molecular mechanism are far to be elucidated. The present study has attempted to probe into the effect of microRNA-33 on MEFs senescence. Our data unveiled that microRNA-33 was dramatically down-regulated in senescent MEFs compared to the young MEFs, and ectopic expression of microRNA-33 promoted MEFs senescence, while knock-down of microRNA-33 exhibited a protective effect against senescence phenotype. Moreover, we verified CDK6 as a direct target of microRNA-33 in mouse. Silencing of CDK6 induced the premature senescence phenotype of MEFs similarly as microRNA-33, while enforced expression of CDK6 significantly reverse the senescence-induction effect of microRNA-33. Taken together, our results suggested that microRNA-33 enhanced the replicative senescence of MEFs potentially by suppressing CDK6 expression. -- Highlights: •MicroRNA-33 was dramatically down-regulated in senescent MEF cells. •Altered expression of microRNA-33 exerted a critical role in MEFs senescence. •MicroRNA-33 promoted the replicative senescence of MEFs via targeting of CDK6.

  4. MicroRNA-33 promotes the replicative senescence of mouse embryonic fibroblasts by suppressing CDK6

    International Nuclear Information System (INIS)

    Xu, Shun; Huang, Haijiao; Li, Nanhong; Zhang, Bing; Jia, Yubin; Yang, Yukun; Yuan, Yuan; Xiong, Xing-dong; Wang, Dengchuan; Zheng, Hui-ling; Liu, Xinguang

    2016-01-01

    MicroRNAs are a large class of tiny noncoding RNAs, which have emerged as critical regulators of gene expression, and thus are involved in multiple cellular processes, including cellular senescence. MicroRNA-33 has previously been established to exert crucial effect on cell proliferation, lipid metabolism and cholesterol metabolism. Nonetheless, the association between microRNA-33 and cellular senescence and its underlying molecular mechanism are far to be elucidated. The present study has attempted to probe into the effect of microRNA-33 on MEFs senescence. Our data unveiled that microRNA-33 was dramatically down-regulated in senescent MEFs compared to the young MEFs, and ectopic expression of microRNA-33 promoted MEFs senescence, while knock-down of microRNA-33 exhibited a protective effect against senescence phenotype. Moreover, we verified CDK6 as a direct target of microRNA-33 in mouse. Silencing of CDK6 induced the premature senescence phenotype of MEFs similarly as microRNA-33, while enforced expression of CDK6 significantly reverse the senescence-induction effect of microRNA-33. Taken together, our results suggested that microRNA-33 enhanced the replicative senescence of MEFs potentially by suppressing CDK6 expression. -- Highlights: •MicroRNA-33 was dramatically down-regulated in senescent MEF cells. •Altered expression of microRNA-33 exerted a critical role in MEFs senescence. •MicroRNA-33 promoted the replicative senescence of MEFs via targeting of CDK6.

  5. Automatic extraction of nuclei centroids of mouse embryonic cells from fluorescence microscopy images.

    Directory of Open Access Journals (Sweden)

    Md Khayrul Bashar

    Full Text Available Accurate identification of cell nuclei and their tracking using three dimensional (3D microscopic images is a demanding task in many biological studies. Manual identification of nuclei centroids from images is an error-prone task, sometimes impossible to accomplish due to low contrast and the presence of noise. Nonetheless, only a few methods are available for 3D bioimaging applications, which sharply contrast with 2D analysis, where many methods already exist. In addition, most methods essentially adopt segmentation for which a reliable solution is still unknown, especially for 3D bio-images having juxtaposed cells. In this work, we propose a new method that can directly extract nuclei centroids from fluorescence microscopy images. This method involves three steps: (i Pre-processing, (ii Local enhancement, and (iii Centroid extraction. The first step includes two variations: first variation (Variant-1 uses the whole 3D pre-processed image, whereas the second one (Variant-2 modifies the preprocessed image to the candidate regions or the candidate hybrid image for further processing. At the second step, a multiscale cube filtering is employed in order to locally enhance the pre-processed image. Centroid extraction in the third step consists of three stages. In Stage-1, we compute a local characteristic ratio at every voxel and extract local maxima regions as candidate centroids using a ratio threshold. Stage-2 processing removes spurious centroids from Stage-1 results by analyzing shapes of intensity profiles from the enhanced image. An iterative procedure based on the nearest neighborhood principle is then proposed to combine if there are fragmented nuclei. Both qualitative and quantitative analyses on a set of 100 images of 3D mouse embryo are performed. Investigations reveal a promising achievement of the technique presented in terms of average sensitivity and precision (i.e., 88.04% and 91.30% for Variant-1; 86.19% and 95.00% for Variant-2

  6. Maintaining the pluripotency of mouse embryonic stem cells on gold nanoparticle layers with nanoscale but not microscale surface roughness

    Science.gov (United States)

    Lyu, Zhonglin; Wang, Hongwei; Wang, Yanyun; Ding, Kaiguo; Liu, Huan; Yuan, Lin; Shi, Xiujuan; Wang, Mengmeng; Wang, Yanwei; Chen, Hong

    2014-05-01

    Efficient control of the self-renewal and pluripotency maintenance of embryonic stem cell (ESC) is a prerequisite for translating stem cell technologies to clinical applications. Surface topography is one of the most important factors that regulates cell behaviors. In the present study, micro/nano topographical structures composed of a gold nanoparticle layer (GNPL) with nano-, sub-micro-, and microscale surface roughnesses were used to study the roles of these structures in regulating the behaviors of mouse ESCs (mESCs) under feeder-free conditions. The distinctive results from Oct-4 immunofluorescence staining and quantitative real-time polymerase chain reaction (qPCR) demonstrate that nanoscale and low sub-microscale surface roughnesses (Rq less than 392 nm) are conducive to the long-term maintenance of mESC pluripotency, while high sub-microscale and microscale surface roughnesses (Rq greater than 573 nm) result in a significant loss of mESC pluripotency and a faster undirectional differentiation, particularly in long-term culture. Moreover, the likely signalling cascades engaged in the topological sensing of mESCs were investigated and their role in affecting the maintenance of the long-term cell pluripotency was discussed by analyzing the expression of proteins related to E-cadherin mediated cell-cell adhesions and integrin-mediated focal adhesions (FAs). Additionally, the conclusions from MTT, cell morphology staining and alkaline phosphatase (ALP) activity assays show that the surface roughness can provide a potent regulatory signal for various mESC behaviors, including cell attachment, proliferation and osteoinduction.Efficient control of the self-renewal and pluripotency maintenance of embryonic stem cell (ESC) is a prerequisite for translating stem cell technologies to clinical applications. Surface topography is one of the most important factors that regulates cell behaviors. In the present study, micro/nano topographical structures composed of a gold

  7. Cellular phenotype-dependent and -independent effects of vitamin C on the renewal and gene expression of mouse embryonic fibroblasts.

    Directory of Open Access Journals (Sweden)

    Shiu-Ming Kuo

    Full Text Available Vitamin C has been shown to delay the cellular senescence and was considered a candidate for chemoprevention and cancer therapy. To understand the reported contrasting roles of vitamin C: growth-promoting in the primary cells and growth-inhibiting in cancer cells, primary mouse embryonic fibroblasts (MEF and their isogenic spontaneously immortalized fibroblasts with unlimited cell division potential were used as the model pair. We used microarray gene expression profiling to show that the immortalized MEF possess human cancer gene expression fingerprints including a pattern of up-regulation of inflammatory response-related genes. Using the MEF model, we found that a physiological treatment level of vitamin C (10(-5 M, but not other unrelated antioxidants, enhanced cell growth. The growth-promoting effect was associated with a pattern of enhanced expression of cell cycle- and cell division-related genes in both primary and immortalized cells. In the immortalized MEF, physiological treatment levels of vitamin C also enhanced the expression of immortalization-associated genes including a down-regulation of genes in the extracellular matrix functional category. In contrast, confocal immunofluorescence imaging of the primary MEF suggested an increase in collagen IV protein upon vitamin C treatment. Similar to the cancer cells, the growth-inhibitory effect of the redox-active form of vitamin C was preferentially observed in immortalized MEF. All effects of vitamin C required its intracellular presence since the transporter-deficient SVCT2-/- MEF did not respond to vitamin C. SVCT2-/- MEF divided and became immortalized readily indicating little dependence on vitamin C for the cell division. Immortalized SVCT2-/- MEF required higher concentration of vitamin C for the growth inhibition compared to the immortalized wildtype MEF suggesting an intracellular vitamin C toxicity. The relevance of our observation in aging and human cancer prevention was

  8. Interkinetic nuclear migration in the mouse embryonic ureteric epithelium: Possible implication for congenital anomalies of the kidney and urinary tract.

    Science.gov (United States)

    Motoya, Tomoyuki; Ogawa, Noriko; Nitta, Tetsuya; Rafiq, Ashiq Mahmood; Jahan, Esrat; Furuya, Motohide; Matsumoto, Akihiro; Udagawa, Jun; Otani, Hiroki

    2016-05-01

    Interkinetic nuclear migration (INM) is a phenomenon in which progenitor cell nuclei migrate along the apico-basal axis of the pseudostratified epithelium, which is characterized by the presence of apical primary cilia, in synchrony with the cell cycle in a manner of apical mitosis. INM is suggested to regulate not only stem/progenitor cell proliferation/differentiation but also organ size and shape. INM has been reported in epithelia of both ectoderm and endoderm origin. We examined whether INM exists in the mesoderm-derived ureteric epithelium. At embryonic day (E) 11.5, E12.5 and E13.5, C57BL/6J mouse dams were injected with 5-bromo-2'-deoxyuridine (BrdU) and embryos were killed 1, 2, 4, 6, 8, 10 and 12 h later. We immunostained transverse sections of the ureter for BrdU, and measured the position of BrdU (+) nuclei in the ureteric epithelia along the apico-basal axis at each time point. We analyzed the distribution patterns of BrdU (+) nuclei in histograms using the multidimensional scaling. Changes in the nucleus distribution patterns suggested nucleus movement characteristic of INM in the ureteric epithelia, and the mode of INM varied throughout the ureter development. While apical primary cilia are related with INM by providing a centrosome for the apical mitosis, congenital anomalies of the kidney and urinary tract (CAKUT) include syndromes linked to primary ciliary dysfunction affecting epithelial tubular organs such as kidney, ureter, and brain. The present study showed that INM exists in the ureteric epithelium and suggests that INM may be related with the CAKUT etiology via primary ciliary protein function. © 2015 Japanese Teratology Society.

  9. Efficient production of platelets from mouse embryonic stem cells by enforced expression of Gata2 in late hemogenic endothelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Kawaguchi, Manami [Stem Cell Project, Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo, 156-8506 (Japan); Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510 (Japan); Kitajima, Kenji [Stem Cell Project, Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo, 156-8506 (Japan); Kanokoda, Mai [Stem Cell Project, Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo, 156-8506 (Japan); Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510 (Japan); Suzuki, Hidenori [Division of Morphological and Biomolecular Research, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo, 113-8602 (Japan); Miyashita, Kazuya; Nakajima, Marino [Stem Cell Project, Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo, 156-8506 (Japan); Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510 (Japan); Nuriya, Hideko [Core Technology and Research Center, Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo, 156-8506 (Japan); Kasahara, Kohji [Laboratory of Biomembrane, Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo, 156-8506 (Japan); Hara, Takahiko, E-mail: hara-tk@igakuken.or.jp [Stem Cell Project, Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo, 156-8506 (Japan); Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510 (Japan)

    2016-06-03

    Platelets are essential for blood circulation and coagulation. Previous study indicated that overexpression of Gata2 in differentiated mouse embryonic stem cells (ESCs) resulted in robust induction of megakaryocytes (Mks). To evaluate platelet production capacity of the Gata2-induced ESC-derived Mks, we generated iGata2-ESC line carrying the doxycycline-inducible Gata2 expression cassette. When doxycycline was added to day 5 hemogenic endothelial cells in the in vitro differentiation culture of iGata2-ESCs, c-Kit{sup −}Tie2{sup −}CD41{sup +} Mks were predominantly generated. These iGata2-ESC-derived Mks efficiently produced CD41{sup +}CD42b{sup +}CD61{sup +} platelets and adhered to fibrinogen-coated glass coverslips in response to thrombin stimulation. Transmission electron microscopy analysis demonstrated that the iGata2-ESC-derived platelets were discoid-shaped with α-granules and an open canalicular system, but were larger than peripheral blood platelets in size. These results demonstrated that an enforced expression of Gata2 in late HECs of differentiated ESCs efficiently promotes megakaryopoiesis followed by platelet production. This study provides valuable information for ex vivo platelet production from human pluripotent stem cells in future. -- Highlights: •Megakaryocytes are efficiently induced by Gata2 from ESC-derived day 5 HECs. •Gata2-induced ESC-derived megakaryocytes are c-Kit{sup −}Tie2{sup −}CD41{sup +}. •Gata2-induced ESC-derived megakaryocytes produce larger discoid-shaped platelets. •Gata2-induced ESC-derived platelets bind fibrinogen upon thrombin stimulation.

  10. Efficient production of platelets from mouse embryonic stem cells by enforced expression of Gata2 in late hemogenic endothelial cells

    International Nuclear Information System (INIS)

    Kawaguchi, Manami; Kitajima, Kenji; Kanokoda, Mai; Suzuki, Hidenori; Miyashita, Kazuya; Nakajima, Marino; Nuriya, Hideko; Kasahara, Kohji; Hara, Takahiko

    2016-01-01

    Platelets are essential for blood circulation and coagulation. Previous study indicated that overexpression of Gata2 in differentiated mouse embryonic stem cells (ESCs) resulted in robust induction of megakaryocytes (Mks). To evaluate platelet production capacity of the Gata2-induced ESC-derived Mks, we generated iGata2-ESC line carrying the doxycycline-inducible Gata2 expression cassette. When doxycycline was added to day 5 hemogenic endothelial cells in the in vitro differentiation culture of iGata2-ESCs, c-Kit − Tie2 − CD41 + Mks were predominantly generated. These iGata2-ESC-derived Mks efficiently produced CD41 + CD42b + CD61 + platelets and adhered to fibrinogen-coated glass coverslips in response to thrombin stimulation. Transmission electron microscopy analysis demonstrated that the iGata2-ESC-derived platelets were discoid-shaped with α-granules and an open canalicular system, but were larger than peripheral blood platelets in size. These results demonstrated that an enforced expression of Gata2 in late HECs of differentiated ESCs efficiently promotes megakaryopoiesis followed by platelet production. This study provides valuable information for ex vivo platelet production from human pluripotent stem cells in future. -- Highlights: •Megakaryocytes are efficiently induced by Gata2 from ESC-derived day 5 HECs. •Gata2-induced ESC-derived megakaryocytes are c-Kit − Tie2 − CD41 + . •Gata2-induced ESC-derived megakaryocytes produce larger discoid-shaped platelets. •Gata2-induced ESC-derived platelets bind fibrinogen upon thrombin stimulation.

  11. Explanation for excessive DNA single-strand breaks and endogenous repair foci in pluripotent mouse embryonic stem cells.

    Science.gov (United States)

    Banáth, J P; Bañuelos, C A; Klokov, D; MacPhail, S M; Lansdorp, P M; Olive, P L

    2009-05-01

    Pluripotent mouse embryonic stem cells (mES cells) exhibit approximately 100 large gammaH2AX repair foci in the absence of measurable numbers of DNA double-strand breaks. Many of these cells also show excessive numbers of DNA single-strand breaks (>10,000 per cell) when analyzed using the alkaline comet assay. To understand the reasons for these unexpected observations, various methods for detecting DNA strand breaks were applied to wild-type mES cells and to mES cells lacking H2AX, ATM, or DNA-PKcs. H2AX phosphorylation and expression of other repair complexes were measured using flow and image analysis of antibody-stained cells. Results indicate that high numbers of endogenous gammaH2AX foci and single-strand breaks in pluripotent mES cells do not require ATM or DNA-PK kinase activity and appear to be associated with global chromatin decondensation rather than pre-existing DNA damage. This will limit applications of gammaH2AX foci analysis in mES cells to relatively high levels of initial or residual DNA damage. Excessive numbers of single-strand breaks in the alkaline comet assay can be explained by the vulnerability of replicating chromatin in mES cells to osmotic shock. This suggests that caution is needed in interpreting results with the alkaline comet assay when applied to certain cell types or after treatment with agents that make chromatin vulnerable to osmotic changes. Differentiation of mES cells caused a reduction in histone acetylation, gammaH2AX foci intensity, and DNA single-strand breakage, providing a link between chromatin structural organization, excessive gammaH2AX foci, and sensitivity of replicating mES cell chromatin to osmotic shock.

  12. The stabilization of hypoxia inducible factor modulates differentiation status and inhibits the proliferation of mouse embryonic stem cells.

    Science.gov (United States)

    Binó, Lucia; Kučera, Jan; Štefková, Kateřina; Švihálková Šindlerová, Lenka; Lánová, Martina; Kudová, Jana; Kubala, Lukáš; Pacherník, Jiří

    2016-01-25

    Hypoxic conditions are suggested to affect the differentiation status of stem cells (SC), including embryonic stem cells (ESC). Hypoxia inducible factor (HIF) is one of the main intracellular molecules responsible for the cellular response to hypoxia. Hypoxia stabilizes HIF by inhibiting the activity of HIF prolyl-hydroxylases (PHD), which are responsible for targeting HIF-alpha subunits for proteosomal degradation. To address the impact of HIF stabilization on the maintenance of the stemness signature of mouse ESC (mESC), we tested the influence of the inhibition of PHDs and hypoxia (1% O2 and 5% O2) on spontaneous ESC differentiation triggered by leukemia inhibitory factor withdrawal for 24 and 48 h. The widely used panhydroxylase inhibitor dimethyloxaloylglycine (DMOG) and PHD inhibitor JNJ-42041935 (JNJ) with suggested higher specificity towards PHDs were employed. Both inhibitors and both levels of hypoxia significantly increased HIF-1alpha and HIF-2alpha protein levels and HIF transcriptional activity in spontaneously differentiating mESC. This was accompanied by significant downregulation of cell proliferation manifested by the complete inhibition of DNA synthesis and partial arrest in the S phase after 48 h. Further, HIF stabilization enhanced downregulation of the expressions of some pluripotency markers (OCT-4, NANOG, ZFP-42, TNAP) in spontaneously differentiating mESC. However, at the same time, there was also a significant decrease in the expression of some genes selected as markers of cell differentiation (e.g. SOX1, BRACH T, ELF5). In conclusion, the short term stabilization of HIF mediated by the PHD inhibitors JNJ and DMOG and hypoxia did not prevent the spontaneous loss of pluripotency markers in mESC. However, it significantly downregulated the proliferation of these cells. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  13. SVM classifier to predict genes important for self-renewal and pluripotency of mouse embryonic stem cells

    Directory of Open Access Journals (Sweden)

    Xu Huilei

    2010-12-01

    Full Text Available Abstract Background Mouse embryonic stem cells (mESCs are derived from the inner cell mass of a developing blastocyst and can be cultured indefinitely in-vitro. Their distinct features are their ability to self-renew and to differentiate to all adult cell types. Genes that maintain mESCs self-renewal and pluripotency identity are of interest to stem cell biologists. Although significant steps have been made toward the identification and characterization of such genes, the list is still incomplete and controversial. For example, the overlap among candidate self-renewal and pluripotency genes across different RNAi screens is surprisingly small. Meanwhile, machine learning approaches have been used to analyze multi-dimensional experimental data and integrate results from many studies, yet they have not been applied to specifically tackle the task of predicting and classifying self-renewal and pluripotency gene membership. Results For this study we developed a classifier, a supervised machine learning framework for predicting self-renewal and pluripotency mESCs stemness membership genes (MSMG using support vector machines (SVM. The data used to train the classifier was derived from mESCs-related studies using mRNA microarrays, measuring gene expression in various stages of early differentiation, as well as ChIP-seq studies applied to mESCs profiling genome-wide binding of key transcription factors, such as Nanog, Oct4, and Sox2, to the regulatory regions of other genes. Comparison to other classification methods using the leave-one-out cross-validation method was employed to evaluate the accuracy and generality of the classification. Finally, two sets of candidate genes from genome-wide RNA interference screens are used to test the generality and potential application of the classifier. Conclusions Our results reveal that an SVM approach can be useful for prioritizing genes for functional validation experiments and complement the analyses of high

  14. Oct3/4 directly regulates expression of E2F3a in mouse embryonic stem cells

    International Nuclear Information System (INIS)

    Kanai, Dai; Ueda, Atsushi; Akagi, Tadayuki; Yokota, Takashi; Koide, Hiroshi

    2015-01-01

    Embryonic stem (ES) cells, derived from the inner cell mass of blastocysts, have a characteristic cell cycle with truncated G1 and G2 phases. Recent findings that suppression of Oct3/4 expression results in a reduced proliferation rate of ES cells suggest the involvement of Oct3/4 in the regulation of ES cell growth, although the underlying molecular mechanism remains unclear. In the present study, we identified E2F3a as a direct target gene of Oct3/4 in ES cells. Oct3/4 directly bound to the promoter region of the E2F3a gene and positively regulated expression of E2F3a in mouse ES cells. Suppression of E2F3a activity by E2F6 overexpression led to the reduced proliferation in ES cells, which was relieved by co-expression of E2F3a. Furthermore, cell growth retardation caused by loss of Oct3/4 was rescued by E2F3a expression. These results suggest that Oct3/4 upregulates E2F3a expression to promote ES cell growth. - Highlights: • Oct3/4 positively regulates E2F3a expression in ES cells. • Oct3/4 binds to the promoter region of the E2F3a gene. • Overexpression of E2F6, an inhibitor of E2F3a, reduces ES cell growth. • E2F3a recovers growth retardation of ES cells caused by Oct3/4 reduction

  15. Oct3/4 directly regulates expression of E2F3a in mouse embryonic stem cells

    Energy Technology Data Exchange (ETDEWEB)

    Kanai, Dai; Ueda, Atsushi; Akagi, Tadayuki; Yokota, Takashi; Koide, Hiroshi, E-mail: hkoide@med.kanazawa-u.ac.jp

    2015-04-10

    Embryonic stem (ES) cells, derived from the inner cell mass of blastocysts, have a characteristic cell cycle with truncated G1 and G2 phases. Recent findings that suppression of Oct3/4 expression results in a reduced proliferation rate of ES cells suggest the involvement of Oct3/4 in the regulation of ES cell growth, although the underlying molecular mechanism remains unclear. In the present study, we identified E2F3a as a direct target gene of Oct3/4 in ES cells. Oct3/4 directly bound to the promoter region of the E2F3a gene and positively regulated expression of E2F3a in mouse ES cells. Suppression of E2F3a activity by E2F6 overexpression led to the reduced proliferation in ES cells, which was relieved by co-expression of E2F3a. Furthermore, cell growth retardation caused by loss of Oct3/4 was rescued by E2F3a expression. These results suggest that Oct3/4 upregulates E2F3a expression to promote ES cell growth. - Highlights: • Oct3/4 positively regulates E2F3a expression in ES cells. • Oct3/4 binds to the promoter region of the E2F3a gene. • Overexpression of E2F6, an inhibitor of E2F3a, reduces ES cell growth. • E2F3a recovers growth retardation of ES cells caused by Oct3/4 reduction.

  16. Thy-1 attenuates TNF-alpha-activated gene expression in mouse embryonic fibroblasts via Src family kinase.

    Directory of Open Access Journals (Sweden)

    Bin Shan

    Full Text Available Heterogeneous surface expression of Thy-1 in fibroblasts modulates inflammation and may thereby modulate injury and repair. As a paradigm, patients with idiopathic pulmonary fibrosis, a disease with pathologic features of chronic inflammation, demonstrate an absence of Thy-1 immunoreactivity within areas of fibrotic activity (fibroblast foci in contrast to the predominant Thy-1 expressing fibroblasts in the normal lung. Likewise, Thy-1 deficient mice display more severe lung fibrosis in response to an inflammatory injury than wildtype littermates. We investigated the role of Thy-1 in the response of fibroblasts to the pro-inflammatory cytokine TNF-alpha. Our study demonstrates distinct profiles of TNF-alpha-activated gene expression in Thy-1 positive (Thy-1+ and negative (Thy-1- subsets of mouse embryonic fibroblasts (MEF. TNF-alpha induced a robust activation of MMP-9, ICAM-1, and the IL-8 promoter driven reporter in Thy-1- MEFs, in contrast to only a modest increase in Thy-1+ counterparts. Consistently, ectopic expression of Thy-1 in Thy-1- MEFs significantly attenuated TNF-alpha-activated gene expression. Mechanistically, TNF-alpha activated Src family kinase (SFK only in Thy-1- MEFs. Blockade of SFK activation abrogated TNF-alpha-activated gene expression in Thy-1- MEFs, whereas restoration of SFK activation rescued the TNF-alpha response in Thy-1+ MEFs. Our findings suggest that Thy-1 down-regulates TNF-alpha-activated gene expression via interfering with SFK- and NF-kappaB-mediated transactivation. The current study provides a novel mechanistic insight to the distinct roles of fibroblast Thy-1 subsets in inflammation.

  17. [Regulation of in vitro and in vivo differentiation of mouse embryonic stem cells, embryonic germ cells, and teratocarcinoma cells by TGFb family signaling factors].

    Science.gov (United States)

    Gordeeva, O F; Nikonova, T M; Lifantseva, N V

    2009-01-01

    The activity of specific signaling and transcription factors determines the cell fate in normal development and in tumor transformation. The transcriptional profiles of gene-components of different branches of TGFbeta family signaling pathways were studied in experimental models of initial stages of three-dimensional in vitro differentiation of embryonic stem cells, embryonic germ cells and teratocarcinoma cells and in teratomas and teratocarcinomas developed after their transplantation into immunodeficient Nude mice. Gene profile analysis of studied cell systems have revealed that expression patterns of ActivinA, Nodal, Lefty1, Lefty2, TGF TGFbeta1, BMP4, and GDF were identical in pluripotent stem cells whereas the mRNAs of all examined genes with the exception of Inhibin betaA/ActivinA were detected in the teratocarcinoma cells. These results indicate that differential activity of signaling pathways of the TGFbeta family factors regulates pluripotent state maintenance and pluripotent stem cell differentiation into the progenitors of three germ layers and extraembryonic structures and that normal expression pattern of TGFbeta family factors is rearranged in embryonic teratocarcinoma cells during tumor growth in vitro and in vivo.

  18. I-SceI-mediated double-strand break does not increase the frequency of homologous recombination at the Dct locus in mouse embryonic stem cells.

    Science.gov (United States)

    Fenina, Myriam; Simon-Chazottes, Dominique; Vandormael-Pournin, Sandrine; Soueid, Jihane; Langa, Francina; Cohen-Tannoudji, Michel; Bernard, Bruno A; Panthier, Jean-Jacques

    2012-01-01

    Targeted induction of double-strand breaks (DSBs) at natural endogenous loci was shown to increase the rate of gene replacement by homologous recombination in mouse embryonic stem cells. The gene encoding dopachrome tautomerase (Dct) is specifically expressed in melanocytes and their precursors. To construct a genetic tool allowing the replacement of Dct gene by any gene of interest, we generated an embryonic stem cell line carrying the recognition site for the yeast I-SceI meganuclease embedded in the Dct genomic segment. The embryonic stem cell line was electroporated with an I-SceI expression plasmid, and a template for the DSB-repair process that carried sequence homologies to the Dct target. The I-SceI meganuclease was indeed able to introduce a DSB at the Dct locus in live embryonic stem cells. However, the level of gene targeting was not improved by the DSB induction, indicating a limited capacity of I-SceI to mediate homologous recombination at the Dct locus. These data suggest that homologous recombination by meganuclease-induced DSB may be locus dependent in mammalian cells.

  19. Circadian oscillators in the mouse brain

    DEFF Research Database (Denmark)

    Rath, Martin F; Rovsing, Louise; Møller, Morten

    2014-01-01

    with conditional cell-specific clock gene deletions. This prompted us to analyze the molecular clockwork of the mouse neocortex and cerebellum in detail. Here, by use of in situ hybridization and quantitative RT-PCR, we show that clock genes are expressed in all six layers of the neocortex and the Purkinje...... and granular cell layers of the cerebellar cortex of the mouse brain. Among these, Per1, Per2, Cry1, Arntl, and Nr1d1 exhibit circadian rhythms suggesting that local running circadian oscillators reside within neurons of the mouse neocortex and cerebellar cortex. The temporal expression profiles of clock genes...... are similar in the neocortex and cerebellum, but they are delayed by 5 h as compared to the SCN, suggestively reflecting a master-slave relationship between the SCN and extra-hypothalamic oscillators. Furthermore, ARNTL protein products are detectable in neurons of the mouse neocortex and cerebellum...

  20. Irreversible barrier to the reprogramming of donor cells in cloning with mouse embryos and embryonic stem cells.

    Science.gov (United States)

    Ono, Yukiko; Kono, Tomohiro

    2006-08-01

    Somatic cloning does not always result in ontogeny in mammals, and development is often associated with various abnormalities and embryo loss with a high frequency. This is considered to be due to aberrant gene expression resulting from epigenetic reprogramming errors. However, a fundamental question in this context is whether the developmental abnormalities reported to date are specific to somatic cloning. The aim of this study was to determine the stage of nuclear differentiation during development that leads to developmental abnormalities associated with embryo cloning. In order to address this issue, we reconstructed cloned embryos using four- and eight-cell embryos, morula embryos, inner cell mass (ICM) cells, and embryonic stem cells as donor nuclei and determined the occurrence of abnormalities such as developmental arrest and placentomegaly, which are common characteristics of all mouse somatic cell clones. The present analysis revealed that an acute decline in the full-term developmental competence of cloned embryos occurred with the use of four- and eight-cell donor nuclei (22.7% vs. 1.8%) in cases of standard embryo cloning and with morula and ICM donor nuclei (11.4% vs. 6.6%) in serial nuclear transfer. Histological observation showed abnormal differentiation and proliferation of trophoblastic giant cells in the placentae of cloned concepti derived from four-cell to ICM cell donor nuclei. Enlargement of placenta along with excessive proliferation of the spongiotrophoblast layer and glycogen cells was observed in the clones derived from morula embryos and ICM cells. These results revealed that irreversible epigenetic events had already started to occur at the four-cell stage. In addition, the expression of genes involved in placentomegaly is regulated at the blastocyst stage by irreversible epigenetic events, and it could not be reprogrammed by the fusion of nuclei with unfertilized oocytes. Hence, developmental abnormalities such as placentomegaly as

  1. Elevated nuclear sphingoid base-1-phosphates and decreased histone deacetylase activity after fumonisin B1 treatment in mouse embryonic fibroblasts

    Energy Technology Data Exchange (ETDEWEB)

    Gardner, Nicole M., E-mail: nicolegardner@creighton.edu [Department of Pharmacology, Creighton University School of Medicine, Omaha, NE 68178 (United States); Riley, Ronald T.; Showker, Jency L.; Voss, Kenneth A. [USDA-ARS, Toxicology and Mycotoxin Research Unit, Athens, GA 30605 (United States); Sachs, Andrew J.; Maddox, Joyce R.; Gelineau-van Waes, Janee B. [Department of Pharmacology, Creighton University School of Medicine, Omaha, NE 68178 (United States)

    2016-05-01

    Fumonisin B1 (FB1) is a mycotoxin produced by a common fungal contaminant of corn. Administration of FB1 to pregnant LM/Bc mice induces exencephaly in embryos, and ingestion of FB1-contaminated food during early pregnancy is associated with increased risk for neural tube defects (NTDs) in humans. FB1 inhibits ceramide synthase enzymes in sphingolipid biosynthesis, causing sphinganine (Sa) and bioactive sphinganine-1-phosphate (Sa1P) accumulation in blood, cells, and tissues. Sphingosine kinases (Sphk) phosphorylate Sa to form Sa1P. Upon activation, Sphk1 associates primarily with the plasma membrane, while Sphk2 is found predominantly in the nucleus. In cells over-expressing Sphk2, accumulation of Sa1P in the nuclear compartment inhibits histone deacetylase (HDAC) activity, causing increased acetylation of histone lysine residues. In this study, FB1 treatment in LM/Bc mouse embryonic fibroblasts (MEFs) resulted in significant accumulation of Sa1P in nuclear extracts relative to cytoplasmic extracts. Elevated nuclear Sa1P corresponded to decreased histone deacetylase (HDAC) activity and increased histone acetylation at H2BK12, H3K9, H3K18, and H3K23. Treatment of LM/Bc MEFs with a selective Sphk1 inhibitor, PF-543, or with ABC294640, a selective Sphk2 inhibitor, significantly reduced nuclear Sa1P accumulation after FB1, although Sa1P levels remained significantly increased relative to basal levels. Concurrent treatment with both PF-543 and ABC294640 prevented nuclear accumulation of Sa1P in response to FB1. Other HDAC inhibitors are known to cause NTDs, so these results suggest that FB1-induced disruption of sphingolipid metabolism leading to nuclear Sa1P accumulation, HDAC inhibition, and histone hyperacetylation is a potential mechanism for FB1-induced NTDs. - Highlights: • FB1 treatment results in accumulation of Sa1P primarily in the nucleus of MEFs. • FB1 treatment and elevated nuclear Sa1P are associated with HDAC inhibition. • Sphk2 inhibition alone

  2. TRANSGENIC GDNF POSITIVELY INFLUENCES PROLIFERATION, DIFFERENTIATION, MATURATION AND SURVIVAL OF MOTOR NEURONS PRODUCED FROM MOUSE EMBRYONIC STEM CELLS.

    Directory of Open Access Journals (Sweden)

    Daniel Édgar Cortés

    2016-09-01

    Full Text Available Embryonic stem cells (ESC are pluripotent and thus can differentiate into every cell type present in the body. Directed differentiation into motor neurons has been described for pluripotent cells. Although neurotrophic factors promote neuronal survival, their role in neuronal commitment is elusive. Here, we developed double-transgenic lines of mouse ESC that constitutively produce Glial cell-derived neurotrophic factor (GDNF and also contain a GFP reporter, driven by HB9, which is expressed only by postmitotic motor neurons. After lentiviral transduction, ESC lines integrated and expressed the human GDNF gene without altering pluripotency markers before differentiation. Further, GDNF-ESC showed significantly higher spontaneous release of this neurotrophin to the medium, when compared to controls. To study motor neuron induction, control and GDNF cell lines were grown as embryoid bodies and stimulated with retinoic acid and Sonic Hedgehog. In GDNF-overexpressing cells, a significant increase of proliferative Olig2+ precursors, which are specified as spinal motor neurons, was found. Accordingly, GDNF increases the yield of cells with the pan motor neuronal markers HB9, monitored by GFP expression, and Isl1. At terminal differentiation, almost all differentiated neurons express phenotypic markers of motor neurons in GDNF cultures, with lower proportions in control cells. To test if the effects of GDNF were present at early differentiation stages, exogenous recombinant human GDNF was added to control ESC, also resulting in enhanced motor neuron differentiation. This effect was abolished by the co-addition of neutralizing anti-GDNF antibodies, strongly suggesting that differentiating ESC are responsive to GDNF. Using the HB9::GFP reporter, motor neurons were selected for electrophysiological recordings. Motor neurons differentiated from GDNF-ESC, compared to control motor neurons, showed greater electrophysiological maturation, characterized by

  3. Elevated nuclear sphingoid base-1-phosphates and decreased histone deacetylase activity after fumonisin B1 treatment in mouse embryonic fibroblasts

    International Nuclear Information System (INIS)

    Gardner, Nicole M.; Riley, Ronald T.; Showker, Jency L.; Voss, Kenneth A.; Sachs, Andrew J.; Maddox, Joyce R.; Gelineau-van Waes, Janee B.

    2016-01-01

    Fumonisin B1 (FB1) is a mycotoxin produced by a common fungal contaminant of corn. Administration of FB1 to pregnant LM/Bc mice induces exencephaly in embryos, and ingestion of FB1-contaminated food during early pregnancy is associated with increased risk for neural tube defects (NTDs) in humans. FB1 inhibits ceramide synthase enzymes in sphingolipid biosynthesis, causing sphinganine (Sa) and bioactive sphinganine-1-phosphate (Sa1P) accumulation in blood, cells, and tissues. Sphingosine kinases (Sphk) phosphorylate Sa to form Sa1P. Upon activation, Sphk1 associates primarily with the plasma membrane, while Sphk2 is found predominantly in the nucleus. In cells over-expressing Sphk2, accumulation of Sa1P in the nuclear compartment inhibits histone deacetylase (HDAC) activity, causing increased acetylation of histone lysine residues. In this study, FB1 treatment in LM/Bc mouse embryonic fibroblasts (MEFs) resulted in significant accumulation of Sa1P in nuclear extracts relative to cytoplasmic extracts. Elevated nuclear Sa1P corresponded to decreased histone deacetylase (HDAC) activity and increased histone acetylation at H2BK12, H3K9, H3K18, and H3K23. Treatment of LM/Bc MEFs with a selective Sphk1 inhibitor, PF-543, or with ABC294640, a selective Sphk2 inhibitor, significantly reduced nuclear Sa1P accumulation after FB1, although Sa1P levels remained significantly increased relative to basal levels. Concurrent treatment with both PF-543 and ABC294640 prevented nuclear accumulation of Sa1P in response to FB1. Other HDAC inhibitors are known to cause NTDs, so these results suggest that FB1-induced disruption of sphingolipid metabolism leading to nuclear Sa1P accumulation, HDAC inhibition, and histone hyperacetylation is a potential mechanism for FB1-induced NTDs. - Highlights: • FB1 treatment results in accumulation of Sa1P primarily in the nucleus of MEFs. • FB1 treatment and elevated nuclear Sa1P are associated with HDAC inhibition. • Sphk2 inhibition alone

  4. Enhancement of Spontaneous Activity by HCN4 Overexpression in Mouse Embryonic Stem Cell-Derived Cardiomyocytes - A Possible Biological Pacemaker.

    Directory of Open Access Journals (Sweden)

    Yukihiro Saito

    Full Text Available Establishment of a biological pacemaker is expected to solve the persisting problems of a mechanical pacemaker including the problems of battery life and electromagnetic interference. Enhancement of the funny current (If flowing through hyperpolarization-activated cyclic nucleotide-gated (HCN channels and attenuation of the inward rectifier K+ current (IK1 flowing through inward rectifier potassium (Kir channels are essential for generation of a biological pacemaker. Therefore, we generated HCN4-overexpressing mouse embryonic stem cells (mESCs and induced cardiomyocytes that originally show poor IK1 currents, and we investigated whether the HCN4-overexpressing mESC-derived cardiomyocytes (mESC-CMs function as a biological pacemaker in vitro.The rabbit Hcn4 gene was transfected into mESCs, and stable clones were selected. mESC-CMs were generated via embryoid bodies and purified under serum/glucose-free and lactate-supplemented conditions. Approximately 90% of the purified cells were troponin I-positive by immunostaining. In mESC-CMs, expression level of the Kcnj2 gene encoding Kir2.1, which is essential for generation of IK1 currents that are responsible for stabilizing the resting membrane potential, was lower than that in an adult mouse ventricle. HCN4-overexpressing mESC-CMs expressed about a 3-times higher level of the Hcn4 gene than did non-overexpressing mESC-CMs. Expression of the Cacna1h gene, which encodes T-type calcium channel and generates diastolic depolarization in the sinoatrial node, was also confirmed. Additionally, genes required for impulse conduction including Connexin40, Connexin43, and Connexin45 genes, which encode connexins forming gap junctions, and the Scn5a gene, which encodes sodium channels, are expressed in the cells. HCN4-overexpressing mESC-CMs showed significantly larger If currents and more rapid spontaneous beating than did non-overexpressing mESC-CMs. The beating rate of HCN4-overexpressing mESC-CMs responded

  5. ZFP57 maintains the parent-of-origin-specific expression of the imprinted genes and differentially affects non-imprinted targets in mouse embryonic stem cells

    DEFF Research Database (Denmark)

    Riso, Vincenzo; Cammisa, Marco; Kukreja, Harpreet

    2016-01-01

    ZFP57 is necessary for maintaining repressive epigenetic modifications at Imprinting control regions (ICRs). In mouse embryonic stem cells (ESCs), ZFP57 binds ICRs (ICRBS) and many other loci (non-ICRBS). To address the role of ZFP57 on all its target sites, we performed high-throughput and multi......-locus analyses of inbred and hybrid mouse ESC lines carrying different gene knockouts. By using an allele-specific RNA-seq approach, we demonstrate that ZFP57 loss results in derepression of the imprinted allele of multiple genes in the imprinted clusters. We also find marked epigenetic differences between ICRBS...... the imprinted expression over long distances. At non-ICRBS, ZFP57 inactivation results in acquisition of epigenetic features that are characteristic of poised enhancers, suggesting that another function of ZFP57 in early embryogenesis is to repress cis-acting regulatory elements whose activity is not yet...

  6. Wnt/β-catenin and LIF-Stat3 signaling pathways converge on Sp5 to promote mouse embryonic stem cell self-renewal.

    Science.gov (United States)

    Ye, Shoudong; Zhang, Dongming; Cheng, Fei; Wilson, Daniel; Mackay, Jeffrey; He, Kan; Ban, Qian; Lv, Feng; Huang, Saifei; Liu, Dahai; Ying, Qi-Long

    2016-01-15

    Activation of leukemia inhibitor factor (LIF)-Stat3 or Wnt/β-catenin signaling promotes mouse embryonic stem cell (mESC) self-renewal. A myriad of downstream targets have been identified in the individual signal pathways, but their common targets remain largely elusive. In this study, we found that the LIF-Stat3 and Wnt/β-catenin signaling pathways converge on Sp5 to promote mESC self-renewal. Forced Sp5 expression can reproduce partial effects of Wnt/β-catenin signaling but mimics most features of LIF-Stat3 signaling to maintain undifferentiated mESCs. Moreover, Sp5 is able to convert mouse epiblast stem cells into a naïve pluripotent state. Thus, Sp5 is an important component of the regulatory network governing mESC naïve pluripotency. © 2016. Published by The Company of Biologists Ltd.

  7. RISC-mediated control of selected chromatin regulators stabilizes ground state pluripotency of mouse embryonic stem cells.

    Science.gov (United States)

    Pandolfini, Luca; Luzi, Ettore; Bressan, Dario; Ucciferri, Nadia; Bertacchi, Michele; Brandi, Rossella; Rocchiccioli, Silvia; D'Onofrio, Mara; Cremisi, Federico

    2016-05-06

    Embryonic stem cells are intrinsically unstable and differentiate spontaneously if they are not shielded from external stimuli. Although the nature of such instability is still controversial, growing evidence suggests that protein translation control may play a crucial role. We performed an integrated analysis of RNA and proteins at the transition between naïve embryonic stem cells and cells primed to differentiate. During this transition, mRNAs coding for chromatin regulators are specifically released from translational inhibition mediated by RNA-induced silencing complex (RISC). This suggests that, prior to differentiation, the propensity of embryonic stem cells to change their epigenetic status is hampered by RNA interference. The expression of these chromatin regulators is reinstated following acute inactivation of RISC and it correlates with loss of stemness markers and activation of early cell differentiation markers in treated embryonic stem cells. We propose that RISC-mediated inhibition of specific sets of chromatin regulators is a primary mechanism for preserving embryonic stem cell pluripotency while inhibiting the onset of embryonic developmental programs.

  8. Genome engineering via homologous recombination in mouse embryonic stem (ES cells: an amazingly versatile tool for the study of mammalian biology

    Directory of Open Access Journals (Sweden)

    BABINET CHARLES

    2001-01-01

    Full Text Available The ability to introduce genetic modifications in the germ line of complex organisms has been a long-standing goal of those who study developmental biology. In this regard, the mouse, a favorite model for the study of the mammals, is unique: indeed not only is it possible since the late seventies, to add genes to the mouse genome like in several other complex organisms but also to perform gene replacement and modification. This has been made possible via two technological breakthroughs: 1 the isolation and culture of embryonic stem cells (ES, which have the unique ability to colonize all the tissues of an host embryo including its germ line; 2 the development of methods allowing homologous recombination between an incoming DNA and its cognate chromosomal sequence (gene ''targeting''. As a result, it has become possible to create mice bearing null mutations in any cloned gene (knock-out mice. Such a possibility has revolutionized the genetic approach of almost all aspects of the biology of the mouse. In recent years, the scope of gene targeting has been widened even more, due to the refinement of the knock-out technology: other types of genetic modifications may now be created, including subtle mutations (point mutations, micro deletions or insertions, etc. and chromosomal rearrangements such as large deletions, duplications and translocations. Finally, methods have been devised which permit the creation of conditional mutations, allowing the study of gene function throughout the life of an animal, when gene inactivation entails embryonic lethality. In this paper, we present an overview of the methods and scenarios used for the programmed modification of mouse genome, and we underline their enormous interest for the study of mammalian biology.

  9. Mitomycin-treated undifferentiated embryonic stem cells as a safe and effective therapeutic strategy in a mouse model of Parkinson's disease.

    Directory of Open Access Journals (Sweden)

    Mariana eAcquarone

    2015-04-01

    Full Text Available Parkinson’s disease (PD is an incurable progressive neurodegenerative disorder. Clinical presentation of PD stems largely from the loss of dopaminergic neurons in the nigrostriatal dopaminergic pathway, motivating experimental strategies aimed at replacing dopaminergic innervation by cellular therapy. Transplantation of dopaminergic neurons derived from embryonic stem cells significantly improves motor functions in rodent and non-human primate models of PD. However, protocols to generate dopaminergic neurons from embryonic stem cells generally meet with low efficacy and high risk of teratoma development upon transplantation. To address these issues, we have pre-treated undifferentiated mouse embryonic stem cells (mESCs with the DNA alkylating agent mitomycin C (MMC before transplantation. MMC treatment of cultures prevented tumor formation in a 12-week follow-up after mESCs were injected in nude mice. In 6-OH-dopamine-lesioned mice, intrastriatal injection of MMC-treated mESCs markedly improved motor function without tumor formation for as long as 15 months. Furthermore, we show that halting mitotic activity of undifferentiated mESCs induces a four-fold increase in dopamine release following in vitro differentiation. Our findings indicate that treating mESCs with mitomycin C prior to intrastriatal transplant is an effective strategy that could be further investigated as a novel alternative for treatment of Parkinson's disease.

  10. Optimization of a serum-free culture medium for mouse embryonic stem cells using design of experiments (DoE) methodology.

    Science.gov (United States)

    Knöspel, Fanny; Schindler, Rudolf K; Lübberstedt, Marc; Petzolt, Stephanie; Gerlach, Jörg C; Zeilinger, Katrin

    2010-12-01

    The in vitro culture behaviour of embryonic stem cells (ESC) is strongly influenced by the culture conditions. Current culture media for expansion of ESC contain some undefined substances. Considering potential clinical translation work with such cells, the use of defined media is desirable. We have used Design of Experiments (DoE) methods to investigate the composition of a serum-free chemically defined culture medium for expansion of mouse embryonic stem cells (mESC). Factor screening analysis according to Plackett-Burman revealed that insulin and leukaemia inhibitory factor (LIF) had a significant positive influence on the proliferation activity of the cells, while zinc and L: -cysteine reduced the cell growth. Further analysis using minimum run resolution IV (MinRes IV) design indicates that following factor adjustment LIF becomes the main factor for the survival and proliferation of mESC. In conclusion, DoE screening assays are applicable to develop and to refine culture media for stem cells and could also be employed to optimize culture media for human embryonic stem cells (hESC).

  11. Cytoarchitecture in cultured rat neocortex explants

    NARCIS (Netherlands)

    de Jong, B. M.; Ruijter, J. M.; Romijn, H. J.

    1988-01-01

    Neocortex explants obtained from 6-day-old rat pups and cultured in a serum-free medium from 5 hr to 13 days in vitro (DIV) show preservation of cytoarchitectural characteristics. Major changes in the size of the explants and their layers occur during the first 2 DIV. A radial arrangement of neurons

  12. Requirement of B-Raf, C-Raf, and A-Raf for the growth and survival of mouse embryonic stem cells

    International Nuclear Information System (INIS)

    Guo, Wenjing; Hao, Baixia; Wang, Qian; Lu, Yingying; Yue, Jianbo

    2013-01-01

    Extracellular signal-regulated kinases (ERKs) have been implicated to be dispensable for self-renewal of mouse embryonic stem (ES) cells, and simultaneous inhibition of both ERK signaling and glycogen synthase kinase 3 (GSK3) not only allows mouse ES cells to self-renew independent of extracellular stimuli but also enables more efficient derivation of naïve ES cells from mouse and rat strains. Interestingly, some ERKs stay active in mouse ES cells which are maintained in regular medium containing leukemia inhibitory factor (LIF) and bone morphogenetic protein (BMP). Yet, the upstream signaling for ERK activation and their roles in mouse ES cells, other than promoting or priming differentiation, have not been determined. Here we found that mouse ES cells express three forms of Raf kinases, A-Raf, B-Raf, and C-Raf. Knocking-down each single Raf member failed to affect the sustained ERK activity, neither did A-Raf and B-Raf double knockdown or B-Raf and C-Raf double knockdown change it in ES cells. Interestingly, B-Raf and C-Raf double knockdown, not A-Raf and B-Raf knockdown, inhibited the maximal ERK activation induced by LIF, concomitant with the slower growth of ES cells. On the other hand, A-Raf, B-Raf, and C-Raf triple knockdown markedly inhibited both the maximal and sustained ERK activity in ES cells. Moreover, Raf triple knockdown, similar to the treatment of U-0126, an MEK inhibitor, significantly inhibited the survival and proliferation of ES cells, thereby compromising the colony propagation of mouse ES cells. In summary, our data demonstrate that all three Raf members are required for ERK activation in mouse ES cells and are involved in growth and survival of mouse ES cells. - Highlights: ●Mouse ES (mES) cells express all three Raf members, A-Raf, B-Raf, and C-Raf. ●Leukemia inhibitory factor (LIF) temporally activates ERKs in mES cells. ●B-Raf and C-Raf are required for LIF-induced maximal ERKs activity in mES cells. ●All Raf members are

  13. Requirement of B-Raf, C-Raf, and A-Raf for the growth and survival of mouse embryonic stem cells

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Wenjing; Hao, Baixia; Wang, Qian; Lu, Yingying; Yue, Jianbo, E-mail: jbyue@me.com

    2013-11-01

    Extracellular signal-regulated kinases (ERKs) have been implicated to be dispensable for self-renewal of mouse embryonic stem (ES) cells, and simultaneous inhibition of both ERK signaling and glycogen synthase kinase 3 (GSK3) not only allows mouse ES cells to self-renew independent of extracellular stimuli but also enables more efficient derivation of naïve ES cells from mouse and rat strains. Interestingly, some ERKs stay active in mouse ES cells which are maintained in regular medium containing leukemia inhibitory factor (LIF) and bone morphogenetic protein (BMP). Yet, the upstream signaling for ERK activation and their roles in mouse ES cells, other than promoting or priming differentiation, have not been determined. Here we found that mouse ES cells express three forms of Raf kinases, A-Raf, B-Raf, and C-Raf. Knocking-down each single Raf member failed to affect the sustained ERK activity, neither did A-Raf and B-Raf double knockdown or B-Raf and C-Raf double knockdown change it in ES cells. Interestingly, B-Raf and C-Raf double knockdown, not A-Raf and B-Raf knockdown, inhibited the maximal ERK activation induced by LIF, concomitant with the slower growth of ES cells. On the other hand, A-Raf, B-Raf, and C-Raf triple knockdown markedly inhibited both the maximal and sustained ERK activity in ES cells. Moreover, Raf triple knockdown, similar to the treatment of U-0126, an MEK inhibitor, significantly inhibited the survival and proliferation of ES cells, thereby compromising the colony propagation of mouse ES cells. In summary, our data demonstrate that all three Raf members are required for ERK activation in mouse ES cells and are involved in growth and survival of mouse ES cells. - Highlights: ●Mouse ES (mES) cells express all three Raf members, A-Raf, B-Raf, and C-Raf. ●Leukemia inhibitory factor (LIF) temporally activates ERKs in mES cells. ●B-Raf and C-Raf are required for LIF-induced maximal ERKs activity in mES cells. ●All Raf members are

  14. Acellular Mouse Kidney ECM can be Used as a Three-Dimensional Substrate to Test the Differentiation Potential of Embryonic Stem Cell Derived Renal Progenitors.

    Science.gov (United States)

    Sambi, Manpreet; Chow, Theresa; Whiteley, Jennifer; Li, Mira; Chua, Shawn; Raileanu, Vanessa; Rogers, Ian M

    2017-08-01

    The development of strategies for tissue regeneration and bio-artificial organ development is based on our understanding of embryogenesis. Differentiation protocols attempt to recapitulate the signaling modalities of gastrulation and organogenesis, coupled with cell selection regimens to isolate the cells of choice. This strategy is impeded by the lack of optimal in vitro culture systems since traditional culture systems do not allow for the three-dimensional interaction between cells and the extracellular matrix. While artificial three-dimensional scaffolds are available, using the natural extracellular matrix scaffold is advantageous because it has a distinct architecture that is difficult to replicate. The adult extracellular matrix is predicted to mediate signaling related to tissue repair not embryogenesis but existing similarities between the two argues that the extracellular matrix will influence the differentiation of stem and progenitor cells. Previous studies using undifferentiated embryonic stem cells grown directly on acellular kidney ECM demonstrated that the acellular kidney supported cell growth but limited differentiation occurred. Using mouse kidney extracellular matrix and mouse embryonic stem cells we report that the extracellular matrix can support the development of kidney structures if the stem cells are first differentiated to kidney progenitor cells before being applied to the acellular organ.

  15. 2,3,7,8-Tetrachlorodibenzo-p-dioxin specifically reduces mRNA for the mineralization-related dentin sialophosphoprotein in cultured mouse embryonic molar teeth

    International Nuclear Information System (INIS)

    Kiukkonen, Anu; Sahlberg, Carin; Lukinmaa, Pirjo-Liisa; Alaluusua, Satu; Peltonen, Eija; Partanen, Anna-Maija

    2006-01-01

    Previous studies show that the most toxic dioxin congener, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), interferes with mineralization of the dental matrices in developing mouse and rat teeth. Culture of mouse embryonic molar teeth with TCDD leads to the failure of enamel to be deposited and dentin to undergo mineralization. Lactationally exposed rats show defectively matured enamel and retardation of dentin mineralization. To see if the impaired mineralization is associated with changes in the expression of dentin sialophosphoprotein (Dspp), Bono1 and/or matrix metalloproteinase-20 (MMP-20), thought to be involved in mineralization of the dental hard tissues, we cultured mouse (NMRI) E18 mandibular molars for 3, 5 or 7 days and exposed them to 1 μM TCDD after 2 days of culture. As detected by in situ hybridization of tissue sections, localization and intensity of Bono1 and MMP-20 expression showed no definite difference between the control and exposed tooth explants, suggesting that TCDD does not affect their expression. On the contrary, TCDD reduced or prevented the expression of Dspp in secretory odontoblasts and decreased it in presecretory ameloblasts. The results suggest that the retardation of dentin mineralization by TCDD in mouse molar teeth involves specific interference with Dspp expression

  16. The effect of minimal concentration of ethylene glycol (EG) combined with polyvinylpyrrolidone (PVP) on mouse oocyte survival and subsequent embryonic development following vitrification.

    Science.gov (United States)

    Wang, Yao; Okitsu, Osamu; Zhao, Xiao-Ming; Sun, Yun; Di, Wen; Chian, Ri-Cheng

    2014-01-01

    Vitrification techniques employ a relatively high concentration of cryoprotectant in vitrification solutions. Exposure of oocytes to high concentrations of cryoprotectant is known to damage the oocytes via both cytotoxic and osmotic effects. Therefore, the key to successful vitrification of oocytes is to strike a balance between the usage of minimal concentration of cryoprotectant without compromising their cryoprotective actions. The minimal concentration of ethylene glycol (EG) on mouse oocyte survival and subsequent embryonic development was evaluated following vitrification-warming and parthenogenetic activation. Polyvinylpyrrolidone (PVP) combined with EG on mouse oocyte survival and subsequent embryonic development as well as morphology of the spindle and chromosome alignment were also evaluated. Vitrification system was adapted with JY Straw and the cooling rate was approximately 442-500 °C/min. In contrast, the warming rate was approximately 2,210-2,652 °C/min. Survival rate of oocytes increased significantly when 15 % EG was combined with 2 % PVP in vitrification solution (VS). The effect of combination of EG and PVP was not significant when the concentration of EG was 20 % and higher. Although there were no significant differences in embryonic development, the percentage of abnormal spindle and chromosome alignment was significantly higher in the oocytes without 2 % PVP in VS. Our data provide a proof of principle for oocyte vitrification that may not require a high concentration of cryoprotectant. There are synergic effects of EG combined with PVP for oocyte vitrification, which may provide important information to the field in developing less cytotoxic VS.

  17. Pleiotropy of Glycogen Synthase Kinase-3 Inhibition by CHIR99021 Promotes Self-Renewal of Embryonic Stem Cells from Refractory Mouse Strains

    Science.gov (United States)

    Ye, Shoudong; Tan, Li; Yang, Rongqing; Fang, Bo; Qu, Su; Schulze, Eric N.; Song, Houyan; Ying, Qilong; Li, Ping

    2012-01-01

    Background Inhibition of glycogen synthase kinase-3 (GSK-3) improves the efficiency of embryonic stem (ES) cell derivation from various strains of mice and rats, as well as dramatically promotes ES cell self-renewal potential. β-catenin has been reported to be involved in the maintenance of self-renewal of ES cells through TCF dependent and independent pathway. But the intrinsic difference between ES cell lines from different species and strains has not been characterized. Here, we dissect the mechanism of GSK-3 inhibition by CHIR99021 in mouse ES cells from refractory mouse strains. Methodology/Principal Findings We found that CHIR99021, a GSK-3 specific inhibitor, promotes self-renewal of ES cells from recalcitrant C57BL/6 (B6) and BALB/c mouse strains through stabilization of β-catenin and c-Myc protein levels. Stabilized β-catenin promoted ES self-renewal through two mechanisms. First, β-catenin translocated into the nucleus to maintain stem cell pluripotency in a lymphoid-enhancing factor/T-cell factor–independent manner. Second, β-catenin binds plasma membrane-localized E-cadherin, which ensures a compact, spherical morphology, a hallmark of ES cells. Further, elevated c-Myc protein levels did not contribute significantly to CH-mediated ES cell self-renewal. Instead, the role of c-Myc is dependent on its transformation activity and can be replaced by N-Myc but not L-Myc. β-catenin and c-Myc have similar effects on ES cells derived from both B6 and BALB/c mice. Conclusions/Significance Our data demonstrated that GSK-3 inhibition by CH promotes self-renewal of mouse ES cells with non-permissive genetic backgrounds by regulation of multiple signaling pathways. These findings would be useful to improve the availability of normally non-permissive mouse strains as research tools. PMID:22540008

  18. Protein arginine methyltransferase 7-mediated microRNA-221 repression maintains Oct4, Nanog, and Sox2 levels in mouse embryonic stem cells.

    Science.gov (United States)

    Chen, Tsai-Yu; Lee, Sung-Hun; Dhar, Shilpa S; Lee, Min Gyu

    2018-03-16

    The stemness maintenance of embryonic stem cells (ESCs) requires pluripotency transcription factors, including Oct4, Nanog, and Sox2. We have previously reported that protein arginine methyltransferase 7 (PRMT7), an epigenetic modifier, is an essential pluripotency factor that maintains the stemness of mouse ESCs, at least in part, by down-regulating the expression of the anti-stemness microRNA (miRNA) miR-24-2. To gain greater insight into the molecular basis underlying PRMT7-mediated maintenance of mouse ESC stemness, we searched for new PRMT7-down-regulated anti-stemness miRNAs. Here, we show that miR-221 gene-encoded miR-221-3p and miR-221-5p are anti-stemness miRNAs whose expression levels in mouse ESCs are directly repressed by PRMT7. Notably, both miR-221-3p and miR-221-5p targeted the 3' untranslated regions of mRNA transcripts of the major pluripotency factors Oct4, Nanog, and Sox2 to antagonize mouse ESC stemness. Moreover, miR-221-5p silenced also the expression of its own transcriptional repressor PRMT7. Transfection of miR-221-3p and miR-221-5p mimics induced spontaneous differentiation of mouse ESCs. CRISPR-mediated deletion of the miR-221 gene, as well as specific antisense inhibitors of miR-221-3p and miR-221-5p, inhibited the spontaneous differentiation of PRMT7-depleted mouse ESCs. Taken together, these findings reveal that the PRMT7-mediated repression of miR-221-3p and miR-221-5p expression plays a critical role in maintaining mouse ESC stemness. Our results also establish miR-221-3p and miR-221-5p as anti-stemness miRNAs that target Oct4 , Nanog , and Sox2 mRNAs in mouse ESCs. © 2018 by The American Society for Biochemistry and Molecular Biology, Inc.

  19. Development of an in vitro culture method for stepwise differentiation of mouse embryonic stem cells and induced pluripotent stem cells into mature osteoclasts.

    Science.gov (United States)

    Nishikawa, Keizo; Iwamoto, Yoriko; Ishii, Masaru

    2014-05-01

    The development of methods for differentiation of embryonic stem cells (ESCs) and induced pluripotent stem cell (iPSCs) into functional cells have helped to analyze the mechanism regulating cellular processes and to explore cell-based assays for drug discovery. Although several reports have demonstrated methods for differentiation of mouse ESCs into osteoclast-like cells, it remains unclear whether these methods are applicable for differentiation of iPSCs to osteoclasts. In this study, we developed a simple method for stepwise differentiation of mouse ESCs and iPSCs into bone-resorbing osteoclasts based upon a monoculture approach consisting of three steps. First, based on conventional hanging-drop methods, embryoid bodies (EBs) were produced from mouse ESCs or iPSCs. Second, EBs were cultured in medium supplemented with macrophage colony-stimulating factor (M-CSF), and differentiated to osteoclast precursors, which expressed CD11b. Finally, ESC- or iPSC-derived osteoclast precursors stimulated with receptor activator of nuclear factor-B ligand (RANKL) and M-CSF formed large multinucleated osteoclast-like cells that expressed tartrate-resistant acid phosphatase and were capable of bone resorption. Molecular analysis showed that the expression of osteoclast marker genes such as Nfatc1, Ctsk, and Acp5 are increased in a RANKL-dependent manner. Thus, our procedure is simple and easy and would be helpful for stem cell-based bone research.

  20. An efficient method for generation of bi-allelic null mutant mouse embryonic stem cells and its application for investigating epigenetic modifiers.

    Science.gov (United States)

    Fisher, Cynthia L; Marks, Hendrik; Cho, Lily Ting-Yin; Andrews, Robert; Wormald, Sam; Carroll, Thomas; Iyer, Vivek; Tate, Peri; Rosen, Barry; Stunnenberg, Hendrik G; Fisher, Amanda G; Skarnes, William C

    2017-12-01

    Mouse embryonic stem (ES) cells are a popular model system to study biological processes, though uncovering recessive phenotypes requires inactivating both alleles. Building upon resources from the International Knockout Mouse Consortium (IKMC), we developed a targeting vector for second allele inactivation in conditional-ready IKMC 'knockout-first' ES cell lines. We applied our technology to several epigenetic regulators, recovering bi-allelic targeted clones with a high efficiency of 60% and used Flp recombinase to restore expression in two null cell lines to demonstrate how our system confirms causality through mutant phenotype reversion. We designed our strategy to select against re-targeting the 'knockout-first' allele and identify essential genes in ES cells, including the histone methyltransferase Setdb1. For confirmation, we exploited the flexibility of our system, enabling tamoxifen inducible conditional gene ablation while controlling for genetic background and tamoxifen effects. Setdb1 ablated ES cells exhibit severe growth inhibition, which is not rescued by exogenous Nanog expression or culturing in naive pluripotency '2i' media, suggesting that the self-renewal defect is mediated through pluripotency network independent pathways. Our strategy to generate null mutant mouse ES cells is applicable to thousands of genes and repurposes existing IKMC Intermediate Vectors. © The Author(s) 2017. Published by Oxford University Press on behalf of Nucleic Acids Research.

  1. Effects of Treatment with Bone Morphogenetic Protein 4 and Co-culture on Expression of Piwil2 Gene in Mouse Differentiated Embryonic Stem Cells

    Directory of Open Access Journals (Sweden)

    Mehdi Forouzandeh-Moghadam

    2009-01-01

    Full Text Available Background: Specific growth factors and feeder layers seem to have important roles in in vitroembryonic stem cells (ESCs differentiation. In this study,the effects of bone morphogenetic protein4 (BMP4 and mouse embryonic fibroblasts (MEFs co-culture system on germ cell differentiationfrom mouse ESCs were studied.Materials and Methods: Cell suspension was prepared from one-day-old embryoid body (EBand cultured for four days in DMEM medium containing 20% fetal bovine serum (FBS in thefollowing groups: simple culture (SC, simple culture with BMP4 (SCB, co-culture (CO-C andco-culture with BMP4 (CO-CB. Expression of piwi-like homolog 2 (Piwil2, the germ cell-specificgene, was evaluated in the different study groups by using quantitative real time polymerase chainreaction (RT-PCR. Testis was used as a positive control.Results: The maximum and minimum Piwil2 expression was observed in SC and SCB groups,respectively. A significant difference was observed in Piwil2 expression between SCB and otherstudy groups (p<0.05.Conclusion: The findings of this study showed that neither the addition of BMP4 in culture mediumnor the use of MEFs as a feeder layer have a positive effect on late germ cell induction from mouseESCs.

  2. Mouse but not human embryonic stem cells are deficient in rejoining of ionizing radiation-induced DNA double-strand breaks.

    Science.gov (United States)

    Bañuelos, C A; Banáth, J P; MacPhail, S H; Zhao, J; Eaves, C A; O'Connor, M D; Lansdorp, P M; Olive, P L

    2008-09-01

    Mouse embryonic stem (mES) cells will give rise to all of the cells of the adult mouse, but they failed to rejoin half of the DNA double-strand breaks (dsb) produced by high doses of ionizing radiation. A deficiency in DNA-PK(cs) appears to be responsible since mES cells expressed strand breaks more rapidly. Consistent with more rapid dsb rejoining, H2AX(-/-) mES cells also expressed 6 times more DNA-PK(cs) than wild-type mES cells. Similar results were obtained for ATM(-/-) mES cells. Differentiation of mES cells led to an increase in DNA-PK(cs), an increase in dsb rejoining rate, and a decrease in Ku70/80. Unlike mouse ES, human ES cells were proficient in rejoining of dsb and expressed high levels of DNA-PK(cs). These results confirm the importance of homologous recombination in the accurate repair of double-strand breaks in mES cells, they help explain the chromosome abnormalities associated with deficiencies in H2AX and ATM, and they add to the growing list of differences in the way rodent and human cells deal with DNA damage.

  3. Immuno-detection of cleaved SNAP-25 from differentiated mouse embryonic stem cells provides a sensitive assay for determination of botulinum A toxin and antitoxin potency.

    Science.gov (United States)

    Yadirgi, G; Stickings, P; Rajagopal, S; Liu, Y; Sesardic, D

    2017-12-01

    Botulinum toxin type A is a causative agent of human botulism. Due to high toxicity and ease of production it is classified by the Centres for Disease Control and Prevention as a category A bioterrorism agent. The same serotype, BoNT/A, is also the most widely used in pharmaceutical preparations for treatment of a diverse range of neuromuscular disorders. Traditionally, animals are used to confirm the presence and activity of toxin and to establish neutralizing capabilities of countermeasures in toxin neutralization tests. Cell based assays for BoNT/A have been reported as the most viable alternative to animal models, since they are capable of reflecting all key steps (binding, translocation, internalization and cleavage of intracellular substrate) involved in toxin activity. In this paper we report preliminary development of a simple immunochemical method for specifically detecting BoNT/A cleaved intracellular substrate, SNAP-25, in cell lysates of neurons derived from mouse embryonic stem cells. The assay offers sensitivity of better than 0.1LD50/ml (3fM) which is not matched by other functional assays, including the mouse bioassay, and provides serotype specificity for quantitative detection of BoNT/A and anti-BoNT/A antitoxin. Subject to formal validation, the method described here could potentially be used as a substitute for the mouse bioassay to measure potency and consistency of therapeutic products. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  4. Microstructural imaging of human neocortex in vivo.

    Science.gov (United States)

    Edwards, Luke J; Kirilina, Evgeniya; Mohammadi, Siawoosh; Weiskopf, Nikolaus

    2018-03-24

    The neocortex of the human brain is the seat of higher brain function. Modern imaging techniques, chief among them magnetic resonance imaging (MRI), allow non-invasive imaging of this important structure. Knowledge of the microstructure of the neocortex has classically come from post-mortem histological studies of human tissue, and extrapolations from invasive animal studies. From these studies, we know that the scale of important neocortical structure spans six orders of magnitude, ranging from the size of axonal diameters (microns), to the size of cortical areas responsible for integrating sensory information (centimetres). MRI presents an opportunity to move beyond classical methods, because MRI is non-invasive and MRI contrast is sensitive to neocortical microstructure over all these length scales. MRI thus allows inferences to be made about neocortical microstructure in vivo, i.e. MRI-based in vivo histology. We review recent literature that has applied and developed MRI-based in vivo histology to probe the microstructure of the human neocortex, focusing specifically on myelin, iron, and neuronal fibre mapping. We find that applications such as cortical parcellation (using R 1 maps as proxies for myelin content) and investigation of cortical iron deposition with age (using R 2 * maps) are already contributing to the frontiers of knowledge in neuroscience. Neuronal fibre mapping in the cortex remains challenging in vivo, but recent improvements in diffusion MRI hold promise for exciting applications in the near future. The literature also suggests that utilising multiple complementary quantitative MRI maps could increase the specificity of inferences about neocortical microstructure relative to contemporary techniques, but that further investment in modelling is required to appropriately combine the maps. In vivo histology of human neocortical microstructure is undergoing rapid development. Future developments will improve its specificity, sensitivity, and

  5. RANTES modulates the release of glutamate in human neocortex.

    Science.gov (United States)

    Musante, Veronica; Longordo, Fabio; Neri, Elisa; Pedrazzi, Marco; Kalfas, Fotios; Severi, Paolo; Raiteri, Maurizio; Pittaluga, Anna

    2008-11-19

    The effects of the recombinant chemokine human RANTES (hRANTES) on the release of glutamate from human neocortex glutamatergic nerve endings were investigated. hRANTES facilitated the spontaneous release of d [(3)H]D-aspartate ([(3)H]DASP-) by binding Pertussis toxin-sensitive G-protein-coupled receptors (GPCRs), whose activation caused Ca(2+) mobilization from inositol trisphosphate-sensitive stores and cytosolic tyrosine kinase-mediated phosphorylations. Facilitation of release switched to inhibition when the effects of hRANTES on the 12 mM K(+)-evoked [(3)H]D-ASP exocytosis were studied. Inhibition of exocytosis relied on activation of Pertussis toxin-sensitive GPCRs negatively coupled to adenylyl cyclase. Both hRANTES effects were prevented by met-RANTES, an antagonist at the chemokine receptors (CCRs) of the CCR1, CCR3, and CCR5 subtypes. Interestingly, human neocortex glutamatergic nerve endings seem to possess all three receptor subtypes. Blockade of CCR1 and CCR5 by antibodies against the extracellular domain of CCRs prevented both the hRANTES effect on [(3)H]D-ASP release, whereas blockade of CCR3 prevented inhibition, but not facilitation, of release. The effects of RANTES on the spontaneous and the evoked release of [(3)H]D-ASP were also observed in experiments with mouse cortical synaptosomes, which may therefore represent an appropriate animal model to study RANTES-induced effects on neurotransmission. It is concluded that glutamate transmission can be modulated in opposite directions by RANTES acting at distinct CCR receptor subtypes coupled to different transduction pathways, consistent with the multiple and sometimes contrasting effects of the chemokine.

  6. Insulin: its binding to specific receptors and its stimulation of DNA synthesis and 2',3'-cyclic nucleotide phosphohydrolase in embryonic mouse brain cell cultures

    International Nuclear Information System (INIS)

    Shanker, G.; Pieringer, R.A.

    1986-01-01

    Previously, the authors demonstrated that ornithine decarboxylase was stimulated by insulin in cultures of embryonic mouse brain cells. In the present work, they have investigated the presence and specificity of insulin receptors in these cultures. A time study showed that maximum binding of 125 [I] labelled insulin was around 75 min. Other studies measured the influence of concentration and age on insulin binding. A displacement study using increasing concentrations of cold insulin, glucagon or growth hormone demonstrated that the specificity of the receptors for insulin was rather high. It was also found that insulin displayed a clear dose-dependent stimulation of thymidine incorporation into the brain cells. Insulin also stimulated the glial enzyme 2':3'-cyclic nucleotide phosphohydrolase (CNP-ase). The results suggest a dual role for insulin; it regulates both cell proliferation as well as differentiation

  7. Expression of biomarker genes of differentiation in D3 mouse embryonic stem cells after exposure to different embryotoxicant and non-embryotoxicant model chemicals

    Directory of Open Access Journals (Sweden)

    Andrea C. Romero

    2015-12-01

    Full Text Available There is a necessity to develop in vitro methods for testing embryotoxicity (Romero et al., 2015 [1]. We studied the progress of D3 mouse embryonic stem cells differentiation exposed to model embryotoxicants and non-embryotoxicants chemicals through the expression of biomarker genes. We studied a set of 16 different genes biomarkers of general cellular processes (Cdk1, Myc, Jun, Mixl, Cer and Wnt3, ectoderm formation (Nrcam, Nes, Shh and Pnpla6, mesoderm formation (Mesp1, Vegfa, Myo1e and Hdac7 and endoderm formation (Flk1 and Afp. We offer dose response in order to derive the concentration causing either 50% or 200% of expression of the biomarker gene. These records revealed to be a valuable end-point to predict in vitro the embryotoxicity of chemicals (Romero et al., 2015 [1].

  8. Inducible and reversible suppression of Npm1 gene expression using stably integrated small interfering RNA vector in mouse embryonic stem cells

    International Nuclear Information System (INIS)

    Wang Beibei; Lu Rui; Wang Weicheng; Jin Ying

    2006-01-01

    The tetracycline (Tc)-inducible small interference RNA (siRNA) is a powerful tool for studying gene function in mammalian cells. However, the system is infrequently utilized in embryonic stem (ES) cells. Here, we present First application of the Tc-inducible, stably integrated plasmid-based siRNA system in mouse ES cells to down-regulate expression of Npm1, an essential gene for embryonic development. The physiological role of Npm1 in ES cells has not been defined. Our data show that the knock-down of Npm1 expression by this siRNA system was not only highly efficient, but also Tc- dose- and induction time-dependent. Particularly, the down-regulation of Npm1 expression was reversible. Importantly, suppression of Npm1 expression in ES cells resulted in reduced cell proliferation. Taken together, this system allows for studying gene function in a highly controlled manner, otherwise difficult to achieve in ES cells. Moreover, our results demonstrate that Npm1 is essential for ES cell proliferation

  9. Cytotoxicity and activation of the Wnt/beta-catenin pathway in mouse embryonic stem cells treated with four GSK3 inhibitors.

    Science.gov (United States)

    Naujok, Ortwin; Lentes, Jana; Diekmann, Ulf; Davenport, Claudia; Lenzen, Sigurd

    2014-04-29

    Small membrane-permeable molecules are now widely used during maintenance and differentiation of embryonic stem cells of different species. In particular the glycogen synthase kinase 3 (GSK3) is an interesting target, since its chemical inhibition activates the Wnt/beta-catenin pathway. In the present comparative study four GSK3 inhibitors were characterized. Cytotoxicity and potential to activate the Wnt/beta-catenin pathway were tested using the commonly used GSK3 inhibitors BIO, SB-216763, CHIR-99021, and CHIR-98014. Wnt/beta-catenin-dependent target genes were measured by quantitative PCR to confirm the Wnt-reporter assay and finally EC50-values were calculated. CHIR-99021 and SB-216763 had the lowest toxicities in mouse embryonic stem cells and CHIR-98014 and BIO the highest toxicities. Only CHIR-99021 and CHIR-98014 lead to a strong induction of the Wnt/beta-catenin pathway, whereas BIO and SB-216763 showed a minor or no increase in activation of the Wnt/beta-catenin pathway over the natural ligand Wnt3a. The data from the Wnt-reporter assay were confirmed by gene expression analysis of the TCF/LEF regulated gene T. Out of the four tested GSK3 inhibitors, only CHIR-99021 and CHIR-98014 proved to be potent pharmacological activators of the Wnt/beta-catenin signaling pathway. But only in the case of CHIR-99021 high potency was combined with very low toxicity.

  10. Omcg1 is critically required for mitosis in rapidly dividing mouse intestinal progenitors and embryonic stem cells

    OpenAIRE

    Léguillier, Teddy; Vandormael-Pournin, Sandrine; Artus, Jérôme; Houlard, Martin; Picard, Christel; Bernex, Florence; Robine, Sylvie; Cohen-Tannoudji, Michel

    2012-01-01

    Summary Recent studies have shown that factors involved in transcription-coupled mRNA processing are important for the maintenance of genome integrity. How these processes are linked and regulated in vivo remains largely unknown. In this study, we addressed in the mouse model the function of Omcg1, which has been shown to participate in co-transcriptional processes, including splicing and transcription-coupled repair. Using inducible mouse models, we found that Omcg1 is most critically req...

  11. Comparison of toxicity of smoke from traditional and harm-reduction cigarettes using mouse embryonic stem cells as a novel model for preimplantation development.

    Science.gov (United States)

    Lin, S; Tran, V; Talbot, P

    2009-02-01

    Embryonic stem cells (ESC), which originate from the inner cell mass of blastocysts, are valuable models for testing the effects of toxicants on preimplantation development. In this study, mouse ESC (mESC) were used to compare the toxicity of mainstream (MS) and sidestream (SS) cigarette smoke on cell attachment, survival and proliferation. In addition, smoke from a traditional commercial cigarette was compared with smoke from three harm-reduction brands. MS and SS smoke solutions were made using an analytical smoking machine and tested at three doses using D3 mESC plated on 0.2% gelatin. At 6 and 24 h, images were taken and the number of attached cells was evaluated. Both MS and SS smoke from traditional and harm-reduction cigarettes inhibited cell attachment, survival and proliferation dose dependently. For all brands, SS smoke was more potent than MS smoke. However, removal of the cigarette filter increased the toxicity of MS smoke to that of SS smoke. Both MS and SS smoke from harm-reduction cigarettes were as inhibitory, or more inhibitory, than their counterparts from the traditional brand. When preimplantation mouse embryos were cultured for 1 h in MS or SS smoke solutions from a harm-reduction brand, blastomeres became apoptotic, in agreement with the data obtained using mESC. mESC provide a valuable model for toxicological studies on the preimplantation stage of development and were used to show that MS and SS smoke from traditional and harm-reduction cigarettes are detrimental to embryonic cells prior to implantation.

  12. Mouse survival motor neuron alleles that mimic SMN2 splicing and are inducible rescue embryonic lethality early in development but not late.

    Directory of Open Access Journals (Sweden)

    Suzan M Hammond

    Full Text Available Spinal muscular atrophy (SMA is caused by low survival motor neuron (SMN levels and patients represent a clinical spectrum due primarily to varying copies of the survival motor neuron-2 (SMN2 gene. Patient and animals studies show that disease severity is abrogated as SMN levels increase. Since therapies currently being pursued target the induction of SMN, it will be important to understand the dosage, timing and cellular requirements of SMN for disease etiology and potential therapeutic intervention. This requires new mouse models that can induce SMN temporally and/or spatially. Here we describe the generation of two hypomorphic Smn alleles, Smn(C-T-Neo and Smn(2B-Neo. These alleles mimic SMN2 exon 7 splicing, titre Smn levels and are inducible. They were specifically designed so that up to three independent lines of mice could be generated, herein we describe two. In a homozygous state each allele results in embryonic lethality. Analysis of these mutants indicates that greater than 5% of Smn protein is required for normal development. The severe hypomorphic nature of these alleles is caused by inclusion of a loxP-flanked neomycin gene selection cassette in Smn intron 7, which can be removed with Cre recombinase. In vitro and in vivo experiments demonstrate these as inducible Smn alleles. When combined with an inducible Cre mouse, embryonic lethality caused by low Smn levels can be rescued early in gestation but not late. This provides direct genetic evidence that a therapeutic window for SMN inductive therapies may exist. Importantly, these lines fill a void for inducible Smn alleles. They also provide a base from which to generate a large repertoire of SMA models of varying disease severities when combined with other Smn alleles or SMN2-containing mice.

  13. Lead induces similar gene expression changes in brains of gestationally exposed adult mice and in neurons differentiated from mouse embryonic stem cells.

    Directory of Open Access Journals (Sweden)

    Francisco Javier Sánchez-Martín

    Full Text Available Exposure to environmental toxicants during embryonic life causes changes in the expression of developmental genes that may last for a lifetime and adversely affect the exposed individual. Developmental exposure to lead (Pb, an ubiquitous environmental contaminant, causes deficits in cognitive functions and IQ, behavioral effects, and attention deficit hyperactivity disorder (ADHD. Long-term effects observed after early life exposure to Pb include reduction of gray matter, alteration of myelin structure, and increment of criminal behavior in adults. Despite growing research interest, the molecular mechanisms responsible for the effects of lead in the central nervous system are still largely unknown. To study the molecular changes due to Pb exposure during neurodevelopment, we exposed mice to Pb in utero and examined the expression of neural markers, neurotrophins, transcription factors and glutamate-related genes in hippocampus, cortex, and thalamus at postnatal day 60. We found that hippocampus was the area where gene expression changes due to Pb exposure were more pronounced. To recapitulate gestational Pb exposure in vitro, we differentiated mouse embryonic stem cells (ESC into neurons and treated ESC-derived neurons with Pb for the length of the differentiation process. These neurons expressed the characteristic neuronal markers Tubb3, Syp, Gap43, Hud, Ngn1, Vglut1 (a marker of glutamatergic neurons, and all the glutamate receptor subunits, but not the glial marker Gafp. Importantly, several of the changes observed in Pb-exposed mouse brains in vivo were also observed in Pb-treated ESC-derived neurons, including those affecting expression of Ngn1, Bdnf exon IV, Grin1, Grin2D, Grik5, Gria4, and Grm6. We conclude that our ESC-derived model of toxicant exposure during neural differentiation promises to be a useful model to analyze mechanisms of neurotoxicity induced by Pb and other environmental agents.

  14. Comprehensive Identification of Krüppel-Like Factor Family Members Contributing to the Self-Renewal of Mouse Embryonic Stem Cells and Cellular Reprogramming.

    Directory of Open Access Journals (Sweden)

    Hyojung Jeon

    Full Text Available Pluripotency is maintained in mouse embryonic stem (ES cells and is induced from somatic cells by the activation of appropriate transcriptional regulatory networks. Krüppel-like factor gene family members, such as Klf2, Klf4 and Klf5, have important roles in maintaining the undifferentiated state of mouse ES cells as well as in cellular reprogramming, yet it is not known whether other Klf family members exert self-renewal and reprogramming functions when overexpressed. In this study, we examined whether overexpression of any representative Klf family member, such as Klf1-Klf10, would be sufficient for the self-renewal of mouse ES cells. We found that only Klf2, Klf4, and Klf5 produced leukemia inhibitory factor (LIF-independent self-renewal, although most KLF proteins, if not all, have the ability to occupy the regulatory regions of Nanog, a critical Klf target gene. We also examined whether overexpression of any of Klf1-Klf10 would be sufficient to convert epiblast stem cells into a naïve pluripotent state and found that Klf5 had such reprogramming ability, in addition to Klf2 and Klf4. We also delineated the functional domains of the Klf2 protein for LIF-independent self-renewal and reprogramming. Interestingly, we found that both the N-terminal transcriptional activation and C-terminal zinc finger domains were indispensable for this activity. Taken together, our comprehensive analysis provides new insight into the contribution of Klf family members to mouse ES self-renewal and cellular reprogramming.

  15. Comprehensive Identification of Krüppel-Like Factor Family Members Contributing to the Self-Renewal of Mouse Embryonic Stem Cells and Cellular Reprogramming.

    Science.gov (United States)

    Jeon, Hyojung; Waku, Tsuyoshi; Azami, Takuya; Khoa, Le Tran Phuc; Yanagisawa, Jun; Takahashi, Satoru; Ema, Masatsugu

    2016-01-01

    Pluripotency is maintained in mouse embryonic stem (ES) cells and is induced from somatic cells by the activation of appropriate transcriptional regulatory networks. Krüppel-like factor gene family members, such as Klf2, Klf4 and Klf5, have important roles in maintaining the undifferentiated state of mouse ES cells as well as in cellular reprogramming, yet it is not known whether other Klf family members exert self-renewal and reprogramming functions when overexpressed. In this study, we examined whether overexpression of any representative Klf family member, such as Klf1-Klf10, would be sufficient for the self-renewal of mouse ES cells. We found that only Klf2, Klf4, and Klf5 produced leukemia inhibitory factor (LIF)-independent self-renewal, although most KLF proteins, if not all, have the ability to occupy the regulatory regions of Nanog, a critical Klf target gene. We also examined whether overexpression of any of Klf1-Klf10 would be sufficient to convert epiblast stem cells into a naïve pluripotent state and found that Klf5 had such reprogramming ability, in addition to Klf2 and Klf4. We also delineated the functional domains of the Klf2 protein for LIF-independent self-renewal and reprogramming. Interestingly, we found that both the N-terminal transcriptional activation and C-terminal zinc finger domains were indispensable for this activity. Taken together, our comprehensive analysis provides new insight into the contribution of Klf family members to mouse ES self-renewal and cellular reprogramming.

  16. BTG/Tob family members Tob1 and Tob2 inhibit proliferation of mouse embryonic stem cells via Id3 mRNA degradation

    International Nuclear Information System (INIS)

    Chen, Yuanfan; Wang, Chenchen; Wu, Jenny; Li, Lingsong

    2015-01-01

    The mammalian BTG/Tob family is a group of proteins with anti-proliferative ability, and there are six members including BTG1, BTG2/PC3/Tis21, BTG3/ANA, BTG4/PC3B, Tob1/Tob and Tob2. Among them, Tob subfamily members, specifically Tob1/Tob and Tob2, have the most extensive C-terminal regions. As previously reported, overexpression of BTG/Tob proteins is associated with the inhibition of G1 to S-phase cell cycle progression and decreased cell proliferation in a variety of cell types. Tob subfamily proteins have similar anti-proliferative effects on cell cycle progression in cultured tumor cells. An important unresolved question is whether or not they have function in rapidly proliferating cells, such as embryonic stem cells (ESCs). Tob1 and Tob2 were expressed ubiquitously in mouse ESCs (mESCs), suggesting a possible role in early embryonic development and mESCs. To address the above question and explore the possible functions of the Tob subfamily in ESCs, we established ESCs from different genotypic knockout inner cell mass (ICM). We found that Tob1 −/− , Tob2 −/− , and Tob1/2 double knockout (DKO, Tob1 −/− & Tob2 −/− ) ESCs grew faster than wild type (WT) ESCs without losing pluripotency, and we provide a possible mechanistic explanation for these observations: Tob1 and Tob2 inhibit the cell cycle via degradation of Id3 mRNA, which is a set of directly targeted genes of BMP4 signaling in mESCs that play critical roles in the maintenance of ESC properties. Together, our data suggest that BTG/Tob family protein Tob1 and Tob2 regulation cell proliferation does not compromise the basic properties of mESCs. - Highlights: • We established mouse Tob1/2 double knockout embryonic stem cells. • Tob1 and Tob2 inhibit the proliferation of ESCs without effect on pluripotency. • Tob1 and Tob2 involved in the degradation of Id3 in mESCs

  17. BTG/Tob family members Tob1 and Tob2 inhibit proliferation of mouse embryonic stem cells via Id3 mRNA degradation

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Yuanfan; Wang, Chenchen [Department of Cell Biology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191 (China); Peking University Stem Cell Research Center, China National Center for International Research, Peking University Health Science Center, Beijing 100191 (China); SARI Center for Stem Cell and Nanomedicine, Shanghai Advanced Research Institute, University of Chinese Academy of Sciences, Shanghai 200120 (China); Wu, Jenny [SARI Center for Stem Cell and Nanomedicine, Shanghai Advanced Research Institute, University of Chinese Academy of Sciences, Shanghai 200120 (China); Li, Lingsong, E-mail: lils@sari.ac.cn [Department of Cell Biology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191 (China); Peking University Stem Cell Research Center, China National Center for International Research, Peking University Health Science Center, Beijing 100191 (China); SARI Center for Stem Cell and Nanomedicine, Shanghai Advanced Research Institute, University of Chinese Academy of Sciences, Shanghai 200120 (China)

    2015-07-03

    The mammalian BTG/Tob family is a group of proteins with anti-proliferative ability, and there are six members including BTG1, BTG2/PC3/Tis21, BTG3/ANA, BTG4/PC3B, Tob1/Tob and Tob2. Among them, Tob subfamily members, specifically Tob1/Tob and Tob2, have the most extensive C-terminal regions. As previously reported, overexpression of BTG/Tob proteins is associated with the inhibition of G1 to S-phase cell cycle progression and decreased cell proliferation in a variety of cell types. Tob subfamily proteins have similar anti-proliferative effects on cell cycle progression in cultured tumor cells. An important unresolved question is whether or not they have function in rapidly proliferating cells, such as embryonic stem cells (ESCs). Tob1 and Tob2 were expressed ubiquitously in mouse ESCs (mESCs), suggesting a possible role in early embryonic development and mESCs. To address the above question and explore the possible functions of the Tob subfamily in ESCs, we established ESCs from different genotypic knockout inner cell mass (ICM). We found that Tob1{sup −/−}, Tob2{sup −/−}, and Tob1/2 double knockout (DKO, Tob1{sup −/−} & Tob2{sup −/−}) ESCs grew faster than wild type (WT) ESCs without losing pluripotency, and we provide a possible mechanistic explanation for these observations: Tob1 and Tob2 inhibit the cell cycle via degradation of Id3 mRNA, which is a set of directly targeted genes of BMP4 signaling in mESCs that play critical roles in the maintenance of ESC properties. Together, our data suggest that BTG/Tob family protein Tob1 and Tob2 regulation cell proliferation does not compromise the basic properties of mESCs. - Highlights: • We established mouse Tob1/2 double knockout embryonic stem cells. • Tob1 and Tob2 inhibit the proliferation of ESCs without effect on pluripotency. • Tob1 and Tob2 involved in the degradation of Id3 in mESCs.

  18. E-cadherin acts as a regulator of transcripts associated with a wide range of cellular processes in mouse embryonic stem cells.

    Directory of Open Access Journals (Sweden)

    Francesca Soncin

    Full Text Available We have recently shown that expression of the cell adhesion molecule E-cadherin is required for LIF-dependent pluripotency of mouse embryonic stem (ES cells.In this study, we have assessed global transcript expression in E-cadherin null (Ecad-/- ES cells cultured in either the presence or absence of LIF and compared these to the parental cell line wtD3.We show that LIF has little effect on the transcript profile of Ecad-/- ES cells, with statistically significant transcript alterations observed only for Sp8 and Stat3. Comparison of Ecad-/- and wtD3 ES cells cultured in LIF demonstrated significant alterations in the transcript profile, with effects not only confined to cell adhesion and motility but also affecting, for example, primary metabolic processes, catabolism and genes associated with apoptosis. Ecad-/- ES cells share similar, although not identical, gene expression profiles to epiblast-derived pluripotent stem cells, suggesting that E-cadherin expression may inhibit inner cell mass to epiblast transition. We further show that Ecad-/- ES cells maintain a functional β-catenin pool that is able to induce β-catenin/TCF-mediated transactivation but, contrary to previous findings, do not display endogenous β-catenin/TCF-mediated transactivation. We conclude that loss of E-cadherin in mouse ES cells leads to significant transcript alterations independently of β-catenin/TCF transactivation.

  19. Differentiation and Transplantation of Embryonic Stem Cell-Derived Cone Photoreceptors into a Mouse Model of End-Stage Retinal Degeneration

    Directory of Open Access Journals (Sweden)

    Kamil Kruczek

    2017-06-01

    Full Text Available The loss of cone photoreceptors that mediate daylight vision represents a leading cause of blindness, for which cell replacement by transplantation offers a promising treatment strategy. Here, we characterize cone differentiation in retinas derived from mouse embryonic stem cells (mESCs. Similar to in vivo development, a temporal pattern of progenitor marker expression is followed by the differentiation of early thyroid hormone receptor β2-positive precursors and, subsequently, photoreceptors exhibiting cone-specific phototransduction-related proteins. We establish that stage-specific inhibition of the Notch pathway increases cone cell differentiation, while retinoic acid signaling regulates cone maturation, comparable with their actions in vivo. MESC-derived cones can be isolated in large numbers and transplanted into adult mouse eyes, showing capacity to survive and mature in the subretinal space of Aipl1−/− mice, a model of end-stage retinal degeneration. Together, this work identifies a robust, renewable cell source for cone replacement by purified cell suspension transplantation.

  20. Mouse embryonic stem cells efficiently lipofected with nuclear localization peptide result in a high yield of chimeric mice and retain germline transmission potency.

    Science.gov (United States)

    Ma, Haiching; Liu, Qin; Diamond, Scott L; Pierce, Eric A

    2004-06-01

    Embryonic stem (ES) cells are an important tool in developmental biology, genomics, and transgenic methods, as well as in potential clinical applications such as gene therapy or tissue engineering. Electroporation is the standard transfection method for mouse ES (mES) cells because lipofection is quite inefficient. It is also unclear if mES cells treated with cationic lipids maintain pluripotency. We have developed a simple lipofection method for high efficiency transfection and stable transgene expression by employing the nonclassical nuclear localization signal M9 derived from the heterogeneous nuclear ribonucleoprotein A1. In contrast to using 20 microg DNA for 10 x 10(6) cells via electroporation which resulted in 10-20 positive cells/mm2, M9-assisted lipofection of 2 x 10(5) cells with 2 microg DNA resulted in > 150 positive cells/mm2. Electroporation produced only 0.16% EGFP positive cells with fluorescence intensity (FI) > 1000 by FACS assay, while M9-lipofection produced 36-fold more highly EGFP positive cells (5.75%) with FI > 1000. Using 2.5 x 10(6) ES cells and 6 microg linearized DNA followed by selection with G418, electroporation yielded 17 EGFP expressing colonies, while M9-assisted lipofection yielded 72 EGFP expressing colonies. The mES cells that stably expressed EGFP following M9-assisted lipofection yielded > 66% chimeric mice (8 of 12) and contributed efficiently to the germline. In an example of gene targeting, a knock-in mouse was produced from an ES clone screened from 200 G418-resistant colonies generated via M9-assisted lipofection. To our knowledge, this is the first report of generation of transgenic or knock-in mice obtained from lipofected mES cells and this method may facilitate large scale genomic studies of ES developmental biology or large scale generation of mouse models of human disease. Copyright 2003 Elsevier Inc.

  1. α2 Integrin, extracellular matrix metalloproteinase inducer, and matrix metalloproteinase-3 act sequentially to induce differentiation of mouse embryonic stem cells into odontoblast-like cells

    International Nuclear Information System (INIS)

    Ozeki, Nobuaki; Kawai, Rie; Hase, Naoko; Hiyama, Taiki; Yamaguchi, Hideyuki; Kondo, Ayami; Nakata, Kazuhiko; Mogi, Makio

    2015-01-01

    We previously reported that interleukin 1β acts via matrix metalloproteinase (MMP)-3 to regulate cell proliferation and suppress apoptosis in α2 integrin-positive odontoblast-like cells differentiated from mouse embryonic stem (ES) cells. Here we characterize the signal cascade underpinning odontoblastic differentiation in mouse ES cells. The expression of α2 integrin, extracellular matrix metalloproteinase inducer (Emmprin), and MMP-3 mRNA and protein were all potently increased during odontoblastic differentiation. Small interfering RNA (siRNA) disruption of the expression of these effectors potently suppressed the expression of the odontoblastic biomarkers dentin sialophosphoprotein, dentin matrix protein-1 and alkaline phosphatase, and blocked odontoblast calcification. Our siRNA, western blot and blocking antibody analyses revealed a unique sequential cascade involving α2 integrin, Emmprin and MMP-3 that drives ES cell differentiation into odontoblasts. This cascade requires the interaction between α2 integrin and Emmprin and is potentiated by exogenous MMP-3. Finally, although odontoblast-like cells potently express α2, α6, αV, β1, and β3, integrins, we confirmed that β1 integrin acts as the trigger for ES cell differentiation, apparently in complex with α2 integrin. These results demonstrate a unique and unanticipated role for an α2 integrin-, Emmprin-, and MMP-3-mediated signaling cascade in driving mouse ES cell differentiation into odontoblast-like cells. - Highlights: • Odontoblast differentiation requires activation of α2 integrin, Emmprin and MMP-3. • α2 integrin, Emmprin and MMP-3 form a sequential signaling cascade. • β1 integrin acts a specific trigger for odontoblast differentiation. • The role of these effectors is highly novel and unanticipated

  2. α2 Integrin, extracellular matrix metalloproteinase inducer, and matrix metalloproteinase-3 act sequentially to induce differentiation of mouse embryonic stem cells into odontoblast-like cells

    Energy Technology Data Exchange (ETDEWEB)

    Ozeki, Nobuaki; Kawai, Rie; Hase, Naoko; Hiyama, Taiki; Yamaguchi, Hideyuki [Department of Endodontics, School of Dentistry, Aichi Gakuin University, Nagoya, Aichi 464-8651 (Japan); Kondo, Ayami [Department of Medicinal Biochemistry, School of Pharmacy, Aichi Gakuin University, Nagoya 464-8650 (Japan); Nakata, Kazuhiko [Department of Endodontics, School of Dentistry, Aichi Gakuin University, Nagoya, Aichi 464-8651 (Japan); Mogi, Makio, E-mail: makio@dpc.agu.ac.jp [Department of Medicinal Biochemistry, School of Pharmacy, Aichi Gakuin University, Nagoya 464-8650 (Japan)

    2015-02-01

    We previously reported that interleukin 1β acts via matrix metalloproteinase (MMP)-3 to regulate cell proliferation and suppress apoptosis in α2 integrin-positive odontoblast-like cells differentiated from mouse embryonic stem (ES) cells. Here we characterize the signal cascade underpinning odontoblastic differentiation in mouse ES cells. The expression of α2 integrin, extracellular matrix metalloproteinase inducer (Emmprin), and MMP-3 mRNA and protein were all potently increased during odontoblastic differentiation. Small interfering RNA (siRNA) disruption of the expression of these effectors potently suppressed the expression of the odontoblastic biomarkers dentin sialophosphoprotein, dentin matrix protein-1 and alkaline phosphatase, and blocked odontoblast calcification. Our siRNA, western blot and blocking antibody analyses revealed a unique sequential cascade involving α2 integrin, Emmprin and MMP-3 that drives ES cell differentiation into odontoblasts. This cascade requires the interaction between α2 integrin and Emmprin and is potentiated by exogenous MMP-3. Finally, although odontoblast-like cells potently express α2, α6, αV, β1, and β3, integrins, we confirmed that β1 integrin acts as the trigger for ES cell differentiation, apparently in complex with α2 integrin. These results demonstrate a unique and unanticipated role for an α2 integrin-, Emmprin-, and MMP-3-mediated signaling cascade in driving mouse ES cell differentiation into odontoblast-like cells. - Highlights: • Odontoblast differentiation requires activation of α2 integrin, Emmprin and MMP-3. • α2 integrin, Emmprin and MMP-3 form a sequential signaling cascade. • β1 integrin acts a specific trigger for odontoblast differentiation. • The role of these effectors is highly novel and unanticipated.

  3. 15-Deoxy-Δ12,14-Prostaglandin J2 regulates leukemia inhibitory factor signaling through JAK-STAT pathway in mouse embryonic stem cells

    International Nuclear Information System (INIS)

    Rajasingh, Johnson; Bright, John J.

    2006-01-01

    Embryonic stem (ES) cells are genetically normal, pluripotent cells, capable of self-renewal and differentiation into all cell lineages. While leukemia inhibitory factor (LIF) maintains pluripotency in mouse ES cells, retinoic acid and other nuclear hormones induce neuro-glial differentiation in mouse and human ES cells in culture. Peroxisome-proliferator-activated receptors (PPARs) are ligand-dependent nuclear receptor transcription factors that regulate cell growth and differentiation in many cell types. However, the role of PPARs in the regulation of ES cell growth and differentiation is not known. In this study, we show that LIF induces proliferation and self-renewal of mouse D3-ES cells in culture. However, treatment with 15-Deoxy-Δ 12,14 -Prostaglandin J 2 (15d-PGJ2), a natural ligand for PPARγ, or all-trans retinoic acid (ATRA) results in a dose-dependent decrease in proliferation and self-renewal in D3-ES cells. Immunoprecipitation and Western blot analyses showed that LIF induces tyrosine phosphorylation of JAK1, TYK2 and STAT3 in 30 min and treatment with 15d-PGJ2 or ATRA results in a dose-dependent decrease in LIF-induced phosphorylation of JAK1 and STAT3 in D3-ES cells. However, treatment of D3-ES cells with Ciglitazone or 15d-PGJ2 for 48 h in culture resulted in a dose-dependent increase in PPARγ protein expression. These results suggest that PPARγ agonists regulate LIF signaling through JAK-STAT pathway leading to growth and self-renewal of ES cells

  4. Highly efficient methods to obtain homogeneous dorsal neural progenitor cells from human and mouse embryonic stem cells and induced pluripotent stem cells.

    Science.gov (United States)

    Zhang, Meixiang; Ngo, Justine; Pirozzi, Filomena; Sun, Ying-Pu; Wynshaw-Boris, Anthony

    2018-03-15

    Embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs) have been widely used to generate cellular models harboring specific disease-related genotypes. Of particular importance are ESC and iPSC applications capable of producing dorsal telencephalic neural progenitor cells (NPCs) that are representative of the cerebral cortex and overcome the challenges of maintaining a homogeneous population of cortical progenitors over several passages in vitro. While previous studies were able to derive NPCs from pluripotent cell types, the fraction of dorsal NPCs in this population is small and decreases over several passages. Here, we present three protocols that are highly efficient in differentiating mouse and human ESCs, as well as human iPSCs, into a homogeneous and stable population of dorsal NPCs. These protocols will be useful for modeling cerebral cortical neurological and neurodegenerative disorders in both mouse and human as well as for high-throughput drug screening for therapeutic development. We optimized three different strategies for generating dorsal telencephalic NPCs from mouse and human pluripotent cell types through single or double inhibition of bone morphogenetic protein (BMP) and/or SMAD pathways. Mouse and human pluripotent cells were aggregated to form embryoid bodies in suspension and were treated with dorsomorphin alone (BMP inhibition) or combined with SB431542 (double BMP/SMAD inhibition) during neural induction. Neural rosettes were then selected from plated embryoid bodies to purify the population of dorsal NPCs. We tested the expression of key dorsal NPC markers as well as nonectodermal markers to confirm the efficiency of our three methods in comparison to published and commercial protocols. Single and double inhibition of BMP and/or SMAD during neural induction led to the efficient differentiation of dorsal NPCs, based on the high percentage of PAX6-positive cells and the NPC gene expression profile. There were no statistically

  5. The evolution of neocortex in primates.

    Science.gov (United States)

    Kaas, Jon H

    2012-01-01

    We can learn about the evolution of neocortex in primates through comparative studies of cortical organization in primates and those mammals that are the closest living relatives of primates, in conjunction with brain features revealed by the skull endocasts of fossil archaic primates. Such studies suggest that early primates had acquired a number of features of neocortex that now distinguish modern primates. Most notably, early primates had an array of new visual areas, and those visual areas widely shared with other mammals had been modified. Posterior parietal cortex was greatly expanded with sensorimotor modules for reaching, grasping, and personal defense. Motor cortex had become more specialized for hand use, and the functions of primary motor cortex were enhanced by the addition and development of premotor and cingulate motor areas. Cortical architecture became more varied, and cortical neuron populations became denser overall than in nonprimate ancestors. Primary visual cortex had the densest population of neurons, and this became more pronounced in the anthropoid radiation. Within the primate clade, considerable variability in cortical size, numbers of areas, and architecture evolved. Copyright © 2012 Elsevier B.V. All rights reserved.

  6. Scanning microscopic evaluation on the development of the cerebral cortex in embryonic mouse subjected to γ-irradiation

    International Nuclear Information System (INIS)

    Sun Xuezhi; Inouye, Minoru; Hayasaka, Shizu; Takagishi, Yoshiko; Yamamura, Hideki

    1995-01-01

    Morphological events occurring in the developing cerebral hemispheres of mice exposed to a single dose of 60 Co γ-irradiation 1.5 Gy on embryonic day 13 (E13) were evaluated by scanning microscope. Twenty-four hr after the exposure, both cell debris and surviving cells had poured out into the ventricular lumen. Radial glial fibers were more crumpled than in the controls. By day E15, proliferating cells in different stages of the cell cycle appeared in the ventricular zone. The glial fibers formed a network through the brain mantle. By E17 many migrating cells attached to the disorderly glial fibers appeared in the different layers of the thin cerebral mantle. These findings suggest that development of the glial fibers was interrupted as early as 24 hr after the single exposure, implying that irradiation on the developing brain may disrupt neuronal migration. (author)

  7. Embryonic Stem Cell-Derived Mesenchymal Stem Cells (MSCs) Have a Superior Neuroprotective Capacity Over Fetal MSCs in the Hypoxic-Ischemic Mouse Brain.

    Science.gov (United States)

    Hawkins, Kate E; Corcelli, Michelangelo; Dowding, Kate; Ranzoni, Anna M; Vlahova, Filipa; Hau, Kwan-Leong; Hunjan, Avina; Peebles, Donald; Gressens, Pierre; Hagberg, Henrik; de Coppi, Paolo; Hristova, Mariya; Guillot, Pascale V

    2018-05-01

    Human mesenchymal stem cells (MSCs) have huge potential for regenerative medicine. In particular, the use of pluripotent stem cell-derived mesenchymal stem cells (PSC-MSCs) overcomes the hurdle of replicative senescence associated with the in vitro expansion of primary cells and has increased therapeutic benefits in comparison to the use of various adult sources of MSCs in a wide range of animal disease models. On the other hand, fetal MSCs exhibit faster growth kinetics and possess longer telomeres and a wider differentiation potential than adult MSCs. Here, for the first time, we compare the therapeutic potential of PSC-MSCs (ES-MSCs from embryonic stem cells) to fetal MSCs (AF-MSCs from the amniotic fluid), demonstrating that ES-MSCs have a superior neuroprotective potential over AF-MSCs in the mouse brain following hypoxia-ischemia. Further, we demonstrate that nuclear factor (NF)-κB-stimulated interleukin (IL)-13 production contributes to an increased in vitro anti-inflammatory potential of ES-MSC-conditioned medium (CM) over AF-MSC-CM, thus suggesting a potential mechanism for this observation. Moreover, we show that induced pluripotent stem cell-derived MSCs (iMSCs) exhibit many similarities to ES-MSCs, including enhanced NF-κB signaling and IL-13 production in comparison to AF-MSCs. Future studies should assess whether iMSCs also exhibit similar neuroprotective potential to ES-MSCs, thus presenting a potential strategy to overcome the ethical issues associated with the use of embryonic stem cells and providing a potential source of cells for autologous use against neonatal hypoxic-ischemic encephalopathy in humans. Stem Cells Translational Medicine 2018;7:439-449. © 2018 The Authors Stem Cells Translational Medicine published by Wiley Periodicals, Inc. on behalf of AlphaMed Press.

  8. Oxytocin receptor ligand binding in embryonic tissue and postnatal brain development of the C57BL/6J mouse

    Directory of Open Access Journals (Sweden)

    Elizabeth eHammock

    2013-12-01

    Full Text Available Oxytocin (OXT has drawn increasing attention as a developmentally relevant neuropeptide given its role in the brain regulation of social behavior. It has been suggested that OXT plays an important role in the infant brain during caregiver attachment in nurturing familial contexts, but there is incomplete experimental evidence. Mouse models of OXT system genes have been particularly informative for the role of the OXT system in social behavior, however, the developing brain areas that could respond to ligand activation of the OXT receptor (OXTR have yet to be identified in this species. Here we report new data revealing dynamic ligand-binding distribution of OXTR in the developing mouse brain. Using male and female C57BL/6J mice at postnatal days (P 0, 7, 14, 21, 35, and 60 we quantified OXTR ligand binding in several brain areas which changed across development. Further, we describe OXTR ligand binding in select tissues of the near-term whole embryo at E18.5. Together, these data aid in the interpretation of findings in mouse models of the OXT system and generate new testable hypotheses for developmental roles for OXT in mammalian systems. We discuss our findings in the context of developmental disorders (including autism, attachment biology, and infant physiological regulation.

  9. Marked change in microRNA expression during neuronal differentiation of human teratocarcinoma NTera2D1 and mouse embryonal carcinoma P19 cells

    International Nuclear Information System (INIS)

    Hohjoh, Hirohiko; Fukushima, Tatsunobu

    2007-01-01

    MicroRNAs (miRNAs) are small noncoding RNAs, with a length of 19-23 nucleotides, which appear to be involved in the regulation of gene expression by inhibiting the translation of messenger RNAs carrying partially or nearly complementary sequences to the miRNAs in their 3' untranslated regions. Expression analysis of miRNAs is necessary to understand their complex role in the regulation of gene expression during the development, differentiation and proliferation of cells. Here we report on the expression profile analysis of miRNAs in human teratocarcinoma NTere2D1, mouse embryonic carcinoma P19, mouse neuroblastoma Neuro2a and rat pheochromocytoma PC12D cells, which can be induced into differentiated cells with long neuritic processes, i.e., after cell differentiation, such that the resultant cells look similar to neuronal cells. The data presented here indicate marked changes in the expression of miRNAs, as well as genes related to neuronal development, occurred in the differentiation of NTera2D1 and P19 cells. Significant changes in miRNA expression were not observed in Neuro2a and PC12D cells, although they showed apparent morphologic change between undifferentiated and differentiated cells. Of the miRNAs investigated, the expression of miRNAs belonging to the miR-302 cluster, which is known to be specifically expressed in embryonic stem cells, and of miR-124a specific to the brain, appeared to be markedly changed. The miR-302 cluster was potently expressed in undifferentiated NTera2D1 and P19 cells, but hardly in differentiated cells, such that miR-124a showed an opposite expression pattern to the miR-302 cluster. Based on these observations, it is suggested that the miR-302 cluster and miR-124a may be useful molecular indicators in the assessment of degree of undifferentiation and/or differentiation in the course of neuronal differentiation

  10. Hematopoietic stem cell-derived exosomes promote hematopoietic differentiation of mouse embryonic stem cells in vitro via inhibiting the miR126/Notch1 pathway.

    Science.gov (United States)

    Liao, Feng-Ling; Tan, Lin; Liu, Hua; Wang, Jin-Ju; Ma, Xiao-Tang; Zhao, Bin; Chen, Yanfang; Bihl, Ji; Yang, Yi; Chen, Ri-Ling

    2018-04-01

    Cell-derived exosomes (EXs) can modulate target cell differentiation via microRNAs (miRs) that they carried. Previous studies have shown that miR126 is highly expressed in hematopoietic stem cells (HSCs) and plays a role in hematopoiesis via modulating the Notch pathway that participates in progenitors' cell fate decisions. In this study we investigated whether HSC-derived EXs (HSC-EXs) could affect the differentiation of mouse embryonic stem cells (ESCs) into HSCs. We prepared HSC-EXs con , HSC-EXs sc and HSC-EXs miR126 from control HSCs and the HSCs transfected with scramble control or miR126 mimics, respectively. HSC-EXs were isolated by ultracentrifugation and analyzed using nanoparticle tracking analysis. We incubated the collected EXs with mouse ESCs over a 10-d differentiation induction period, during which HSC-EXs and a Notch pathway activator (Jagged1, 100 ng/mL) were added to the cultures every 3 d. After the 10-d differentiation period, the expression levels of miR126, SSEA1, CD117, Sca1, Notch1 and Hes1 in ESCs were assessed. The generated HSCs were validated by flow cytometry using antibodies against HSC markers (CD117, CD34 and Sca1). Our results revealed that: (1) transfection with miR126 mimics significantly increased miR126 levels in HSC-EXs miR126 . (2) HSC-EX co-culture promoted mouse ESCs differentiation into HSCs with the most prominent effect found in the HSC-EXs miR126 co-culture. (3) HSC differentiation was verified by reduced SSEA1 expression and increased CD117 and Sca1 expression. (4) All the effects caused by HSC-EXs were accompanied by significant reduction of Notch1 and Hes1 expression, thus inhibition of the Notch1/Hes1 pathway, whereas activation of Notch by Jagged1 abolished the effects of HSC-EXs miR126 . In conclusion, HSC-EXs promote hematopoietic differentiation of mouse ESCs in vitro by inhibiting the miR126/Notch1 pathway.

  11. Phosphorylation of ULK1 by AMPK is essential for mouse embryonic stem cell self-renewal and pluripotency.

    Science.gov (United States)

    Gong, Jiaqi; Gu, Haifeng; Zhao, Lin; Wang, Liang; Liu, Pinglei; Wang, Fuping; Xu, Haoyu; Zhao, Tongbiao

    2018-01-18

    Autophagy is a catabolic process to degrade both damaged organelles and aggregated proteins in somatic cells. We have recently identified that autophagy is an executor for mitochondrial homeostasis in embryonic stem cell (ESC), and thus contribute to stemness regulation. However, the regulatory and functional mechanisms of autophagy in ESC are still largely unknown. Here we have shown that activation of ULK1 by AMPK is essential for ESC self-renewal and pluripotency. Dysfunction of Ulk1 decreases the autophagic flux in ESC, leading to compromised self-renewal and pluripotency. These defects can be rescued by reacquisition of wild-type ULK1 and ULK1(S757A) mutant, but not ULK1(S317A, S555A and S777A) and kinase dead ULK1(K46I) mutant. These data indicate that phosphorylation of ULK1 by AMPK, but not mTOR, is essential for stemness regulation in ESC. The findings highlight a critical role for AMPK-dependent phosphorylation of ULK1 pathway to maintain ESC self-renewal and pluripotency.

  12. Protein tyrosine phosphatase 1B (PTP1B) is required for cardiac lineage differentiation of mouse embryonic stem cells.

    Science.gov (United States)

    Eshkiki, Zahra Shokati; Ghahremani, Mohammad Hossein; Shabani, Parisa; Firuzjaee, Sattar Gorgani; Sadeghi, Asie; Ghanbarian, Hossein; Meshkani, Reza

    2017-01-01

    Protein tyrosine phosphatase 1B (PTP1B) has been shown to regulate multiple cellular events such as differentiation, cell growth, and proliferation; however, the role of PTP1B in differentiation of embryonic stem (ES) cells into cardiomyocytes remains unexplored. In the present study, we investigated the effects of PTP1B inhibition on differentiation of ES cells into cardiomyocytes. PTP1B mRNA and protein levels were increased during the differentiation of ES cells into cardiomyocytes. Accordingly, a stable ES cell line expressing PTP1B shRNA was established. In vitro, the number and size of spontaneously beating embryoid bodies were significantly decreased in PTP1B-knockdown cells, compared with the control cells. Decreased expression of cardiac-specific markers Nkx2-5, MHC-α, cTnT, and CX43, as assessed by real-time PCR analysis, was further confirmed by immunocytochemistry of the markers. The results also showed that PTP1B inhibition induced apoptosis in both differentiated and undifferentiated ES cells, as presented by increasing the level of cleaved caspase-3, cytochrome C, and cleaved PARP. Further analyses revealed that PTP1B inhibition did not change proliferation and pluripotency of undifferentiated ES cells. Taken together, the data presented here suggest that PTP1B is essential for proper differentiation of ES cells into cardiomyocytes.

  13. Defined MicroRNAs Induce Aspects of Maturation in Mouse and Human Embryonic-Stem-Cell-Derived Cardiomyocytes

    Directory of Open Access Journals (Sweden)

    Desy S. Lee

    2015-09-01

    Full Text Available Pluripotent-cell-derived cardiomyocytes have great potential for use in research and medicine, but limitations in their maturity currently constrain their usefulness. Here, we report a method for improving features of maturation in murine and human embryonic-stem-cell-derived cardiomyocytes (m/hESC-CMs. We found that coculturing m/hESC-CMs with endothelial cells improves their maturity and upregulates several microRNAs. Delivering four of these microRNAs, miR-125b-5p, miR-199a-5p, miR-221, and miR-222 (miR-combo, to m/hESC-CMs resulted in improved sarcomere alignment and calcium handling, a more negative resting membrane potential, and increased expression of cardiomyocyte maturation markers. Although this could not fully phenocopy all adult cardiomyocyte characteristics, these effects persisted for two months following delivery of miR-combo. A luciferase assay demonstrated that all four miRNAs target ErbB4, and siRNA knockdown of ErbB4 partially recapitulated the effects of miR-combo. In summary, a combination of miRNAs induced via endothelial coculture improved ESC-CM maturity, in part through suppression of ErbB4 signaling.

  14. Low-level laser therapy activates NF-kB via generation of reactive oxygen species in mouse embryonic fibroblasts.

    Directory of Open Access Journals (Sweden)

    Aaron C-H Chen

    Full Text Available Despite over forty years of investigation on low-level light therapy (LLLT, the fundamental mechanisms underlying photobiomodulation at a cellular level remain unclear.In this study, we isolated murine embryonic fibroblasts (MEF from transgenic NF-kB luciferase reporter mice and studied their response to 810 nm laser radiation. Significant activation of NF-kB was observed at fluences higher than 0.003 J/cm(2 and was confirmed by Western blot analysis. NF-kB was activated earlier (1 hour by LLLT compared to conventional lipopolysaccharide treatment. We also observed that LLLT induced intracellular reactive oxygen species (ROS production similar to mitochondrial inhibitors, such as antimycin A, rotenone and paraquat. Furthermore, we observed similar NF-kB activation with these mitochondrial inhibitors. These results, together with inhibition of laser induced NF-kB activation by antioxidants, suggests that ROS play an important role in the laser induced NF-kB signaling pathways. However, LLLT, unlike mitochondrial inhibitors, induced increased cellular ATP levels, which indicates that LLLT also upregulates mitochondrial respiration.We conclude that LLLT not only enhances mitochondrial respiration, but also activates the redox-sensitive NFkB signaling via generation of ROS. Expression of anti-apoptosis and pro-survival genes responsive to NFkB could explain many clinical effects of LLLT.

  15. Dehydrodiconiferyl Alcohol Isolated from Cucurbita moschata Shows Anti-adipogenic and Anti-lipogenic Effects in 3T3-L1 Cells and Primary Mouse Embryonic Fibroblasts*

    Science.gov (United States)

    Lee, Junghun; Kim, Donghyun; Choi, Jonghyun; Choi, Hyounjeong; Ryu, Jae-Ha; Jeong, Jinhyun; Park, Eun-Jin; Kim, Seon-Hee; Kim, Sunyoung

    2012-01-01

    A water-soluble extract from the stems of Cucurbita moschata, code named PG105, was previously found to contain strong anti-obesity activities in a high fat diet-induced obesity mouse model. One of its biological characteristics is that it inhibits 3T3-L1 adipocyte differentiation. To isolate the biologically active compound(s), conventional solvent fractionation was performed, and the various fractions were tested for anti-adipogenic activity using Oil Red O staining method. A single spot on thin layer chromatography of the chloroform fraction showed a potent anti-adipogenic activity. When purified, the structure of its major component was resolved as dehydrodiconiferyl alcohol (DHCA), a lignan, by NMR and mass spectrometry analysis. In 3T3-L1 cells, synthesized DHCA significantly reduced the expression of several adipocyte marker genes, including peroxisome proliferator-activated receptor γ (Pparg), CCAAT/enhancer-binding protein α (Cebpa), fatty acid-binding protein 4 (Fabp4), sterol response element-binding protein-1c (Srebp1c), and stearoyl-coenzyme A desaturase-1 (Scd), and decreased lipid accumulation without affecting cell viability. DHCA also suppressed the mitotic clonal expansion of preadipocytes (an early event of adipogenesis), probably by suppressing the DNA binding activity of C/EBPβ, and lowered the production level of cyclinA and cyclin-dependent kinase 2 (Cdk2), coinciding with the decrease in DNA synthesis and cell division. In addition, DHCA directly inhibited the expression of SREBP-1c and SCD-1. Similar observations were made, using primary mouse embryonic fibroblasts. Taken together, our data indicate that DHCA may contain dual activities, affecting both adipogenesis and lipogenesis. PMID:22262865

  16. Cell cycle-dependent expression of Dub3, Nanog and the p160 family of nuclear receptor coactivators (NCoAs in mouse embryonic stem cells.

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    Siem van der Laan

    Full Text Available Pluripotency of embryonic stem cells (ESC is tightly regulated by a network of transcription factors among which the estrogen-related receptor β (Esrrb. Esrrb contributes to the relaxation of the G1 to S-phase (G1/S checkpoint in mouse ESCs by transcriptional control of the deubiquitylase Dub3 gene, contributing to Cdc25A persistence after DNA damage. We show that in mESCs, Dub3 gene expression is cell cycle regulated and is maximal prior G1/S transition. In addition, following UV-induced DNA damage in G1, Dub3 expression markedly increases in S-phase also suggesting a role in checkpoint recovery. Unexpectedly, we also observed cell cycle-regulation of Nanog expression, and not Oct4, reaching high levels prior to G1/S transition, finely mirroring Cyclin E1 fluctuations. Curiously, while Esrrb showed only limited cell-cycle oscillations, transcript levels of the p160 family of nuclear receptor coactivators (NCoAs displayed strong cell cycle-dependent fluctuations. Since NCoAs function in concert with Esrrb in transcriptional activation, we focussed on NCoA1 whose levels specifically increase prior onset of Dub3 transcription. Using a reporter assay, we show that NCoA1 potentiates Esrrb-mediated transcription of Dub3 and we present evidence of protein interaction between the SRC1 splice variant NCoA1 and Esrrb. Finally, we show a differential developmental regulation of all members of the p160 family during neural conversion of mESCs. These findings suggest that in mouse ESCs, changes in the relative concentration of a coactivator at a given cell cycle phase, may contribute to modulation of the transcriptional activity of the core transcription factors of the pluripotent network and be implicated in cell fate decisions upon onset of differentiation.

  17. Cell cycle-dependent expression of Dub3, Nanog and the p160 family of nuclear receptor coactivators (NCoAs) in mouse embryonic stem cells.

    Science.gov (United States)

    van der Laan, Siem; Golfetto, Eleonora; Vanacker, Jean-Marc; Maiorano, Domenico

    2014-01-01

    Pluripotency of embryonic stem cells (ESC) is tightly regulated by a network of transcription factors among which the estrogen-related receptor β (Esrrb). Esrrb contributes to the relaxation of the G1 to S-phase (G1/S) checkpoint in mouse ESCs by transcriptional control of the deubiquitylase Dub3 gene, contributing to Cdc25A persistence after DNA damage. We show that in mESCs, Dub3 gene expression is cell cycle regulated and is maximal prior G1/S transition. In addition, following UV-induced DNA damage in G1, Dub3 expression markedly increases in S-phase also suggesting a role in checkpoint recovery. Unexpectedly, we also observed cell cycle-regulation of Nanog expression, and not Oct4, reaching high levels prior to G1/S transition, finely mirroring Cyclin E1 fluctuations. Curiously, while Esrrb showed only limited cell-cycle oscillations, transcript levels of the p160 family of nuclear receptor coactivators (NCoAs) displayed strong cell cycle-dependent fluctuations. Since NCoAs function in concert with Esrrb in transcriptional activation, we focussed on NCoA1 whose levels specifically increase prior onset of Dub3 transcription. Using a reporter assay, we show that NCoA1 potentiates Esrrb-mediated transcription of Dub3 and we present evidence of protein interaction between the SRC1 splice variant NCoA1 and Esrrb. Finally, we show a differential developmental regulation of all members of the p160 family during neural conversion of mESCs. These findings suggest that in mouse ESCs, changes in the relative concentration of a coactivator at a given cell cycle phase, may contribute to modulation of the transcriptional activity of the core transcription factors of the pluripotent network and be implicated in cell fate decisions upon onset of differentiation.

  18. A Rapid Embryonic Stem Cell-Based Mouse Model for B-cell Lymphomas Driven by Epstein-Barr Virus Protein LMP1.

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    Ba, Zhaoqing; Meng, Fei-Long; Gostissa, Monica; Huang, Pei-Yi; Ke, Qiang; Wang, Zhe; Dao, Mai N; Fujiwara, Yuko; Rajewsky, Klaus; Zhang, Baochun; Alt, Frederick W

    2015-06-01

    The Epstein-Barr virus (EBV) latent membrane protein 1 (LMP1) contributes to oncogenic human B-cell transformation. Mouse B cells conditionally expressing LMP1 are not predisposed to B-cell malignancies, as LMP1-expressing B cells are eliminated by T cells. However, mice with conditional B-cell LMP1 expression and genetic elimination of α/β and γ/δ T cells ("CLT" mice) die early in association with B-cell lymphoproliferation and lymphomagenesis. Generation of CLT mice involves in-breeding multiple independently segregating alleles. Thus, although introduction of additional activating or knockout mutations into the CLT model is desirable for further B-cell expansion and immunosurveillance studies, doing such experiments by germline breeding is time-consuming, expensive, and sometimes unfeasible. To generate a more tractable model, we generated clonal CLT embryonic stem (ES) cells from CLT embryos and injected them into RAG2-deficient blastocysts to generate chimeric mice, which, like germline CLT mice, harbor splenic CLT B cells and lack T cells. CLT chimeric mice generated by this RAG2-deficient blastocyst complementation ("RDBC") approach die rapidly in association with B-cell lymphoproliferation and lymphoma. Because CLT lymphomas routinely express the activation-induced cytidine deaminase (AID) antibody diversifier, we tested potential AID roles by eliminating the AID gene in CLT ES cells and testing them via RDBC. We found that CLT and AID-deficient CLT ES chimeras had indistinguishable phenotypes, showing that AID is not essential for LMP1-induced lymphomagenesis. Beyond expanding accessibility and utility of CLT mice as a cancer immunotherapy model, our studies provide a new approach for facilitating generation of genetically complex mouse cancer models. ©2015 American Association for Cancer Research.

  19. A CO-FISH assay to assess sister chromatid segregation patterns in mitosis of mouse embryonic stem cells.

    Science.gov (United States)

    Sauer, Stephan; Burkett, Sandra S; Lewandoski, Mark; Klar, Amar J S

    2013-05-01

    Sister chromatids contain identical DNA sequence but are chiral with respect to both their helical handedness and their replication history. Emerging evidence from various model organisms suggests that certain stem cells segregate sister chromatids nonrandomly to either maintain genome integrity or to bias cellular differentiation in asymmetric cell divisions. Conventional methods for tracing of old vs. newly synthesized DNA strands generally lack resolution for individual chromosomes and employ halogenated thymidine analogs with profound cytotoxic effects on rapidly dividing cells. Here, we present a modified chromosome orientation fluorescence in situ hybridization (CO-FISH) assay, where identification of individual chromosomes and their replication history is achieved in subsequent hybridization steps with chromosome-specific DNA probes and PNA telomere probes. Importantly, we tackle the issue of BrdU cytotoxicity and show that our method is compatible with normal mouse ES cell biology, unlike a recently published related protocol. Results from our CO-FISH assay show that mitotic segregation of mouse chromosome 7 is random in ES cells, which contrasts previously published results from our laboratory and settles a controversy. Our straightforward protocol represents a useful resource for future studies on chromatid segregation patterns of in vitro-cultured cells from distinct model organisms.

  20. Mouse embryonic stem cells undergo charontosis, a novel programmed cell death pathway dependent upon cathepsins, p53, and EndoG, in response to etoposide treatment.

    Science.gov (United States)

    Tichy, Elisia D; Stephan, Zachary A; Osterburg, Andrew; Noel, Greg; Stambrook, Peter J

    2013-05-01

    Embryonic stem cells (ESCs) are hypersensitive to many DNA damaging agents and can rapidly undergo cell death or cell differentiation following exposure. Treatment of mouse ESCs (mESCs) with etoposide (ETO), a topoisomerase II poison, followed by a recovery period resulted in massive cell death with characteristics of a programmed cell death pathway (PCD). While cell death was both caspase- and necroptosis-independent, it was partially dependent on the activity of lysosomal proteases. A role for autophagy in the cell death process was eliminated, suggesting that ETO induces a novel PCD pathway in mESCs. Inhibition of p53 either as a transcription factor by pifithrin α or in its mitochondrial role by pifithrin μ significantly reduced ESC death levels. Finally, EndoG was newly identified as a protease participating in the DNA fragmentation observed during ETO-induced PCD. We coined the term charontosis after Charon, the ferryman of the dead in Greek mythology, to refer to the PCD signaling events induced by ETO in mESCs. Copyright © 2013 Elsevier B.V. All rights reserved.

  1. Functional analysis in mouse embryonic stem cells reveals wild-type activity for three MSH6 variants found in suspected Lynch syndrome patients.

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    Eva A L Wielders

    Full Text Available Lynch syndrome confers an increased risk to various types of cancer, in particular early onset colorectal and endometrial cancer. Mutations in mismatch repair (MMR genes underlie Lynch syndrome, with the majority of mutations found in MLH1 and MSH2. Mutations in MSH6 have also been found but these do not always cause a clear cancer predisposition phenotype and MSH6-defective tumors often do not show the standard characteristics of MMR deficiency, such as microsatellite instability. In particular, the consequences of MSH6 missense mutations are challenging to predict, which further complicates genetic counseling. We have previously developed a method for functional characterization of MSH2 missense mutations of unknown significance. This method is based on endogenous gene modification in mouse embryonic stem cells using oligonucleotide-directed gene targeting, followed by a series of functional assays addressing the MMR functions. Here we have adapted this method for the characterization of MSH6 missense mutations. We recreated three MSH6 variants found in suspected Lynch syndrome families, MSH6-P1087R, MSH6-R1095H and MSH6-L1354Q, and found all three to behave like wild type MSH6. Thus, despite suspicion for pathogenicity from clinical observations, our approach indicates these variants are not disease causing. This has important implications for counseling of mutation carriers.

  2. Hydrogen-rich medium protects mouse embryonic fibroblasts from oxidative stress by activating LKB1-AMPK-FoxO1 signal pathway.

    Science.gov (United States)

    Lee, Jihyun; Yang, Goowon; Kim, Young-Joo; Tran, Quynh Hoa; Choe, Wonchae; Kang, Insug; Kim, Sung Soo; Ha, Joohun

    2017-09-23

    Persistent oxidative stress is recognized as a major cause of many pathological conditions as well as ageing. However, most clinical trials of dietary antioxidants have failed to produce successful outcomes in treating oxidative stress-induced diseases. Molecular hydrogen (H 2 ) has recently received considerable attention as a therapeutic agent owing to its novel antioxidant properties, a selective scavenger of hydroxyl and peroxynitrite radicals. Beyond this, numerous reports support that H 2 can modulate the activity of various cellular signal pathways. However, its effect on AMP-activated protein kinase (AMPK) signal pathway, a central regulator of energy hemostasis, has remained almost elusive. Here, we report that hydrogen-rich medium activated LKB1-AMPK signal pathway without ATP depletion, which in turn induced FoxO1-dependent transcription of manganese superoxide dismutase and catalase in mouse embryonic fibroblasts. Moreover, hydrogen-rich media effectively reduced the level of reactive oxygen species in cells treated with hydrogen peroxide and protected these cells from apoptosis in an AMPK-dependent manner. These results suggest that the LKB1-AMPK-FoxO1 signaling pathway is a critical mediator of the antioxidant properties of H 2 , further supporting the idea that H 2 acts as a signaling molecule to serve various physiological functions. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Hypoxia Downregulates MAPK/ERK but Not STAT3 Signaling in ROS-Dependent and HIF-1-Independent Manners in Mouse Embryonic Stem Cells

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    Jan Kučera

    2017-01-01

    Full Text Available Hypoxia is involved in the regulation of stem cell fate, and hypoxia-inducible factor 1 (HIF-1 is the master regulator of hypoxic response. Here, we focus on the effect of hypoxia on intracellular signaling pathways responsible for mouse embryonic stem (ES cell maintenance. We employed wild-type and HIF-1α-deficient ES cells to investigate hypoxic response in the ERK, Akt, and STAT3 pathways. Cultivation in 1% O2 for 24 h resulted in the strong dephosphorylation of ERK and its upstream kinases and to a lesser extent of Akt in an HIF-1-independent manner, while STAT3 phosphorylation remained unaffected. Downregulation of ERK could not be mimicked either by pharmacologically induced hypoxia or by the overexpression. Dual-specificity phosphatases (DUSP 1, 5, and 6 are hypoxia-sensitive MAPK-specific phosphatases involved in ERK downregulation, and protein phosphatase 2A (PP2A regulates both ERK and Akt. However, combining multiple approaches, we revealed the limited significance of DUSPs and PP2A in the hypoxia-mediated attenuation of ERK signaling. Interestingly, we observed a decreased reactive oxygen species (ROS level in hypoxia and a similar phosphorylation pattern for ERK when the cells were supplemented with glutathione. Therefore, we suggest a potential role for the ROS-dependent attenuation of ERK signaling in hypoxia, without the involvement of HIF-1.

  4. Maintenance of Self-Renewal and Pluripotency in J1 Mouse Embryonic Stem Cells through Regulating Transcription Factor and MicroRNA Expression Induced by PD0325901

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    Zhiying Ai

    2016-01-01

    Full Text Available Embryonic stem cells (ESCs have the ability to grow indefinitely and retain their pluripotency in culture, and this self-renewal capacity is governed by several crucial molecular pathways controlled by specific regulatory genes and epigenetic modifications. It is reported that multiple epigenetic regulators, such as miRNA and pluripotency factors, can be tightly integrated into molecular pathways and cooperate to maintain self-renewal of ESCs. However, mouse ESCs in serum-containing medium seem to be heterogeneous due to the self-activating differentiation signal of MEK/ERK. Thus, to seek for the crucial miRNA and key regulatory genes that establish ESC properties in MEK/ERK pathway, we performed microarray analysis and small RNA deep-sequencing of J1 mESCs treated with or without PD0325901 (PD, a well-known inhibitor of MEK/ERK signal pathway, followed by verification of western blot analysis and quantitative real-time PCR verification; we found that PD regulated the transcript expressions related to self-renewal and differentiation and antagonized the action of retinoic acid- (RA- induced differentiation. Moreover, PD can significantly modulate the expressions of multiple miRNAs that have crucial functions in ESC development. Overall, our results demonstrate that PD could enhance ESC self-renewal capacity both by key regulatory genes and ES cell-specific miRNA, which in turn influences ESC self-renewal and cellular differentiation.

  5. A Perturbed MicroRNA Expression Pattern Characterizes Embryonic Neural Stem Cells Derived from a Severe Mouse Model of Spinal Muscular Atrophy (SMA

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    Andrea Luchetti

    2015-08-01

    Full Text Available Spinal muscular atrophy (SMA is an inherited neuromuscular disorder and the leading genetic cause of death in infants. Despite the disease-causing gene, survival motor neuron (SMN1, encodes a ubiquitous protein, SMN1 deficiency preferentially affects spinal motor neurons (MNs, leaving the basis of this selective cell damage still unexplained. As neural stem cells (NSCs are multipotent self-renewing cells that can differentiate into neurons, they represent an in vitro model for elucidating the pathogenetic mechanism of neurodegenerative diseases such as SMA. Here we characterize for the first time neural stem cells (NSCs derived from embryonic spinal cords of a severe SMNΔ7 SMA mouse model. SMNΔ7 NSCs behave as their wild type (WT counterparts, when we consider neurosphere formation ability and the expression levels of specific regional and self-renewal markers. However, they show a perturbed cell cycle phase distribution and an increased proliferation rate compared to wild type cells. Moreover, SMNΔ7 NSCs are characterized by the differential expression of a limited number of miRNAs, among which miR-335-5p and miR-100-5p, reduced in SMNΔ7 NSCs compared to WT cells. We suggest that such miRNAs may be related to the proliferation differences characterizing SMNΔ7 NSCs, and may be potentially involved in the molecular mechanisms of SMA.

  6. A Perturbed MicroRNA Expression Pattern Characterizes Embryonic Neural Stem Cells Derived from a Severe Mouse Model of Spinal Muscular Atrophy (SMA).

    Science.gov (United States)

    Luchetti, Andrea; Ciafrè, Silvia Anna; Murdocca, Michela; Malgieri, Arianna; Masotti, Andrea; Sanchez, Massimo; Farace, Maria Giulia; Novelli, Giuseppe; Sangiuolo, Federica

    2015-08-06

    Spinal muscular atrophy (SMA) is an inherited neuromuscular disorder and the leading genetic cause of death in infants. Despite the disease-causing gene, survival motor neuron (SMN1), encodes a ubiquitous protein, SMN1 deficiency preferentially affects spinal motor neurons (MNs), leaving the basis of this selective cell damage still unexplained. As neural stem cells (NSCs) are multipotent self-renewing cells that can differentiate into neurons, they represent an in vitro model for elucidating the pathogenetic mechanism of neurodegenerative diseases such as SMA. Here we characterize for the first time neural stem cells (NSCs) derived from embryonic spinal cords of a severe SMNΔ7 SMA mouse model. SMNΔ7 NSCs behave as their wild type (WT) counterparts, when we consider neurosphere formation ability and the expression levels of specific regional and self-renewal markers. However, they show a perturbed cell cycle phase distribution and an increased proliferation rate compared to wild type cells. Moreover, SMNΔ7 NSCs are characterized by the differential expression of a limited number of miRNAs, among which miR-335-5p and miR-100-5p, reduced in SMNΔ7 NSCs compared to WT cells. We suggest that such miRNAs may be related to the proliferation differences characterizing SMNΔ7 NSCs, and may be potentially involved in the molecular mechanisms of SMA.

  7. JMJD1C Ensures Mouse Embryonic Stem Cell Self-Renewal and Somatic Cell Reprogramming through Controlling MicroRNA Expression.

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    Xiao, Feng; Liao, Bing; Hu, Jing; Li, Shuang; Zhao, Haixin; Sun, Ming; Gu, Junjie; Jin, Ying

    2017-09-12

    The roles of histone demethylases (HDMs) for the establishment and maintenance of pluripotency are incompletely characterized. Here, we show that JmjC-domain-containing protein 1c (JMJD1C), an H3K9 demethylase, is required for mouse embryonic stem cell (ESC) self-renewal. Depletion of Jmjd1c leads to the activation of ERK/MAPK signaling and epithelial-to-mesenchymal transition (EMT) to induce differentiation of ESCs. Inhibition of ERK/MAPK signaling rescues the differentiation phenotype caused by Jmjd1c depletion. Mechanistically, JMJD1C, with the help of pluripotency factor KLF4, maintains ESC identity at least in part by regulating the expression of the miR-200 family and miR-290/295 cluster to suppress the ERK/MAPK signaling and EMT. Additionally, we uncover that JMJD1C ensures efficient generation and maintenance of induced pluripotent stem cells, at least partially through controlling the expression of microRNAs. Collectively, we propose an integrated model of epigenetic and transcriptional control mediated by the H3K9 demethylase for ESC self-renewal and somatic cell reprogramming. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  8. Improvement of mouse cloning using nuclear transfer-derived embryonic stem cells and/or histone deacetylase inhibitor.

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    Wakayama, Sayaka; Wakayama, Teruhiko

    2010-01-01

    Nuclear transfer-derived ES (ntES) cell lines can be established from somatic cell nuclei with a relatively high success rate. Although ntES cells have been shown to be equivalent to ES cells, there are ethical objections concerning human cells, such as the use of fresh oocyte donation from young healthy woman. In contrast, the use of induced pluripotent stem (iPS) cells for cloning poses few ethical problems and is a relatively easy technique compared with nuclear transfer. Therefore, although there are several reports proposing the use of ntES cells as a model of regenerative medicine, the use of these cells in preliminary medical research is waning. However, in theory, 5 to 10 donor cells can establish one ntES cell line and, once established, these cells will propagate indefinitely. These cells can be used to generate cloned animals from ntES cell lines using a second round of NT. Even in infertile and "unclonable" strains of mice, we can generate offspring from somatic cells by combining cloning with ntES technology. Moreover, cloned offspring can be generated potentially even from the nuclei of dead bodies or freeze-dried cells via ntES cells, such as from an extinct frozen animal. Currently, only the ntES technology is available for this purpose, because all other techniques, including iPS cell derivation, require significant numbers of living donor cells. This review describes how to improve the efficiency of cloning, the establishment of clone-derived embryonic stem cells and further applications.

  9. Effects of Synthetic Neural Adhesion Molecule Mimetic Peptides and Related Proteins on the Cardiomyogenic Differentiation of Mouse Embryonic Stem Cells

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    Ruodan Xu

    2015-04-01

    Full Text Available Background/Aims: Pluripotent stem cells differentiating into cardiomyocyte-like cells in an appropriate cellular environment have attracted significant attention, given the potential use of such cells for regenerative medicine. However, the precise mechanisms of lineage specification of pluripotent stem cells are still largely to be explored. Identifying the role of various small synthetic peptides involved in cardiomyogenesis may provide new insights into pathways promoting cardiomyogenesis. Methods: In the present study, using a transgenic murine embryonic stem (ES cell lineage expressing enhanced green fluorescent protein (EGFP under the control of α-myosin heavy chain (α-MHC promoter (pαMHC-EGFP, we investigated the cardiomyogenic effects of 7 synthetic peptides (Betrofin3, FGLs, FGLL, hNgf_C2, EnkaminE, Plannexin and C3 on cardiac differentiation. The expression of several cardiac-specific markers was determined by RT-PCR whereas the structural and functional properties of derived cardiomyocytes were examined by immunofluorescence and electrophysiology, respectively. Results: The results revealed that Betrofin3, an agonist of brain derived neurotrophic factor (BDNF peptide exerted the most striking pro-cardiomyogenic effect on ES cells. We found that BDNF receptor, TrkB expression was up-regulated during differentiation. Treatment of differentiating cells with Betrofin3 between days 3 and 5 enhanced the expression of cardiac-specific markers and improved cardiomyocyte differentiation and functionality as revealed by genes regulation, flow cytometry and patch clamp analysis. Thus Betrofin3 may exert its cardiomyogenic effects on ES cells via TrkB receptor. Conclusion: Taken together, the results suggest that Betrofin3 modulates BDNF signaling with positive cardiomyogenic effect in stage and dose-dependent manner providing an effective strategy to increase ES cell-based generation of cardiomyocytes and offer a novel therapeutic approach to

  10. In vitro formation of the Merkel cell-neurite complex in embryonic mouse whiskers using organotypic co-cultures.

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    Ishida, Kentaro; Saito, Tetsuichiro; Mitsui, Toshiyuki

    2018-06-01

    A Merkel cell-neurite complex is a touch receptor composed of specialized epithelial cells named Merkel cells and peripheral sensory nerves in the skin. Merkel cells are found in touch-sensitive skin components including whisker follicles. The nerve fibers that innervate Merkel cells of a whisker follicle extend from the maxillary branch of the trigeminal ganglion. Whiskers as a sensory organ attribute to the complicated architecture of the Merkel cell-neurite complex, and therefore it is intriguing how the structure is formed. However, observing the dynamic process of the formation of a Merkel cell-neurite complex in whiskers during embryonic development is still difficult. In this study, we tried to develop an organotypic co-culture method of a whisker pad and a trigeminal ganglion explant to form the Merkel cell-neurite complex in vitro. We initially developed two distinct culture methods of a single whisker row and a trigeminal ganglion explant, and then combined them. By dissecting and cultivating a single row from a whisker pad, the morphogenesis of whisker follicles could be observed under a microscope. After the co-cultivation of the whisker row with a trigeminal ganglion explant, a Merkel cell-neurite complex composed of Merkel cells, which were positive for both cytokeratin 8 and SOX2, Neurofilament-H-positive trigeminal nerve fibers and Schwann cells expressing Nestin, SOX2 and SOX10 was observed via immunohistochemical analyses. These results suggest that the process for the formation of a Merkel cell-neurite complex can be observed under a microscope using our organotypic co-culture method. © 2018 Japanese Society of Developmental Biologists.

  11. Efficient and simple production of insulin-producing cells from embryonal carcinoma stem cells using mouse neonate pancreas extract, as a natural inducer.

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    Marzieh Ebrahimie

    Full Text Available An attractive approach to replace the destroyed insulin-producing cells (IPCs is the generation of functional β cells from stem cells. Embryonal carcinoma (EC stem cells are pluripotent cells which can differentiate into all cell types. The present study was carried out to establish a simple nonselective inductive culture system for generation of IPCs from P19 EC cells by 1-2 weeks old mouse pancreas extract (MPE. Since, mouse pancreatic islets undergo further remodeling and maturation for 2-3 weeks after birth, we hypothesized that the mouse neonatal MPE contains essential factors to induce in vitro differentiation of pancreatic lineages. Pluripotency of P19 cells were first confirmed by expression analysis of stem cell markers, Oct3/4, Sox-2 and Nanog. In order to induce differentiation, the cells were cultured in a medium supplemented by different concentrations of MPE (50, 100, 200 and 300 µg/ml. The results showed that P19 cells could differentiate into IPCs and form dithizone-positive cell clusters. The generated P19-derived IPCs were immunoreactive to proinsulin, insulin and insulin receptor beta. The expression of pancreatic β cell genes including, PDX-1, INS1 and INS2 were also confirmed. The peak response at the 100 µg/ml MPE used for investigation of EP300 and CREB1 gene expression. When stimulated with glucose, these cells synthesized and secreted insulin. Network analysis of the key transcription factors (PDX-1, EP300, CREB1 during the generation of IPCs resulted in introduction of novel regulatory candidates such as MIR17, and VEZF1 transcription factors, as well as MORN1, DKFZp761P0212, and WAC proteins. Altogether, we demonstrated the possibility of generating IPCs from undifferentiated EC cells, with the characteristics of pancreatic β cells. The derivation of pancreatic cells from EC cells which are ES cell siblings would provide a valuable experimental tool in study of pancreatic development and function as well as rapid

  12. Excess thyroid hormone inhibits embryonic neural stem/progenitor cells proliferation and maintenance through STAT3 signalling pathway.

    Science.gov (United States)

    Chen, Chunhai; Zhou, Zhou; Zhong, Min; Li, Maoquan; Yang, Xuesen; Zhang, Yanwen; Wang, Yuan; Wei, Aimin; Qu, Mingyue; Zhang, Lei; Xu, Shangcheng; Chen, Shude; Yu, Zhengping

    2011-07-01

    Hyperthyroidism is prevalent during pregnancy, but little is known about the effects of excess thyroid hormone on the development of embryonic neural stem/progenitor cells (NSCs), and the mechanisms underlying these effects. Previous studies indicate that STAT3 plays a crucial role in determining NSC fate during neurodevelopment. In this study, we investigated the effects of a supraphysiological dose of 3,5,3'-L-triiodothyronine (T3) on the proliferation and maintenance of NSCs derived from embryonic day 13.5 mouse neocortex, and the involvement of STAT3 in this process. Our results suggest that excess T3 treatment inhibits NSC proliferation and maintenance. T3 decreased tyrosine phosphorylation of JAK1, JAK2 and STAT3, and subsequently inhibited STAT3-DNA binding activity. Furthermore, proliferation and maintenance of NSCs were decreased by inhibitors of JAKs and STAT3, indicating that the STAT3 signalling pathway is involved in the process of NSC proliferation and maintenance. Taken together, these results suggest that the STAT3 signalling pathway is involved in the process of T3-induced inhibition of embryonic NSC proliferation and maintenance. These findings provide data for understanding the effects of hyperthyroidism during pregnancy on fetal brain development, and the mechanisms underlying these effects.

  13. Tlx and Pax6 co-operate genetically to establish the pallio-subpallial boundary in the embryonic mouse telencephalon.

    Science.gov (United States)

    Stenman, Jan; Yu, Ruth T; Evans, Ronald M; Campbell, Kenneth

    2003-03-01

    We have examined the role of Tlx, an orphan nuclear receptor, in dorsal-ventral patterning of the mouse telencephalon. Tlx is expressed broadly in the ventricular zone, with the exception of the dorsomedial and ventromedial regions. The expression spans the pallio-subpallial boundary, which separates the dorsal (i.e. pallium) and ventral (i.e. subpallium) telencephalon. Despite being expressed on both sides of the pallio-subpallial boundary, Tlx homozygous mutants display alterations in the development of this boundary. These alterations include a dorsal shift in the expression limits of certain genes that abut at the pallio-subpallial boundary as well as the abnormal formation of the radial glial palisade that normally marks this boundary. The Tlx mutant phenotype is similar to, but less severe than, that seen in Small eye (i.e. Pax6) mutants. Interestingly, removal of one allele of Pax6 on the homozygous Tlx mutant background significantly worsens the phenotype. Thus Tlx and Pax6 cooperate genetically to regulate the establishment of the pallio-subpallial boundary. The patterning defects in the Tlx mutant telencephalon result in a loss of region-specific gene expression in the ventral-most pallial region. This correlates well with the malformation of the lateral and basolateral amygdala in Tlx mutants, both of which have been suggested to derive from ventral portions of the pallium.

  14. Wnt ligands from the embryonic surface ectoderm regulate ‘bimetallic strip’ optic cup morphogenesis in mouse

    Science.gov (United States)

    Carpenter, April C.; Smith, April N.; Wagner, Heidi; Cohen-Tayar, Yamit; Rao, Sujata; Wallace, Valerie; Ashery-Padan, Ruth; Lang, Richard A.

    2015-01-01

    The Wnt/β-catenin response pathway is central to many developmental processes. Here, we assessed the role of Wnt signaling in early eye development using the mouse as a model system. We showed that the surface ectoderm region that includes the lens placode expressed 12 out of 19 possible Wnt ligands. When these activities were suppressed by conditional deletion of wntless (Le-cre; Wlsfl/fl) there were dramatic consequences that included a saucer-shaped optic cup, ventral coloboma, and a deficiency of periocular mesenchyme. This phenotype shared features with that produced when the Wnt/β-catenin pathway co-receptor Lrp6 is mutated or when retinoic acid (RA) signaling in the eye is compromised. Consistent with this, microarray and cell fate marker analysis identified a series of expression changes in genes known to be regulated by RA or by the Wnt/β-catenin pathway. Using pathway reporters, we showed that Wnt ligands from the surface ectoderm directly or indirectly elicit a Wnt/β-catenin response in retinal pigment epithelium (RPE) progenitors near the optic cup rim. In Le-cre; Wlsfl/fl mice, the numbers of RPE cells are reduced and this can explain, using the principle of the bimetallic strip, the curvature of the optic cup. These data thus establish a novel hypothesis to explain how differential cell numbers in a bilayered epithelium can lead to shape change. PMID:25715397

  15. Embryonic death, dwarfism and fetal malformations after irradiation of embryos at the zygote stage. Studies on two mouse strains

    International Nuclear Information System (INIS)

    Jacquet, P.; Saint-Georges, L. de; Baugnet-Mahieu, L.; Vankerkom, J.

    1995-01-01

    Female mice of the BALB/c and CF1 strains were mated and irradiated with various doses of X-rays 7 h after presumed fertilization. 18 days later, females were killed and their uteri examined for prenatal mortality at the different stages of development. Living fetuses were weighed and examined for the presence of external malformations. A number of them were also examined for skeletal anomalies. Radiation induced mainly a dose-dependent increase of the preimplantation loss in the BALB/c strain and of the early postimplantation loss in the CF1 strain. Embryos of the BALB/c strain were refractory to the induction of teratogenic effects after such preimplantation irradiation. In CF1 mice, the frequency of malformed fetuses increased regularly after irradiation, the difference with controls being significant for the doses of 10, 50 and 100 cGy. Dwarfism occurrence also appeared to be increased by irradiation in this strain, although the importance of this effect varied depending on the criterion chosen for the assessment of dwarfs. With the definition proposed in the present paper, the increase in the frequency of dwarfs paralleled that of malformed fetuses, being significant after doses of 50 and 100 cGy. Irradiation did not increase the frequency of skeletal anomalies. A careful examination of the various data obtained to date led us to conclude that radiation may possibly be teratogenic in several mouse strains, when administered as early as during the one-cell stage and, to a lesser extent, during the following preimplantation stages. However, early prenatal mortality will remain by far the greatest risk associated with an exposure to radiation during this period. Moreover, the relativity of the risk of abnormality due to such irradiation should be considered in the context of the high prevalence of developmental defects spontaneously occurring during human pregnancy

  16. Embryonic death, dwarfism and fetal malformations after irradiation of embryos at the zygote stage. Studies on two mouse strains

    Energy Technology Data Exchange (ETDEWEB)

    Jacquet, P.; Saint-Georges, L. de; Baugnet-Mahieu, L. [Laboratory of Radiobiology, Department of Radioprotection, CEN/SCK, Mol (Belgium); Vankerkom, J. [Division of Environmental Research, VITO, Mol (Belgium)

    1995-11-01

    Female mice of the BALB/c and CF1 strains were mated and irradiated with various doses of X-rays 7 h after presumed fertilization. 18 days later, females were killed and their uteri examined for prenatal mortality at the different stages of development. Living fetuses were weighed and examined for the presence of external malformations. A number of them were also examined for skeletal anomalies. Radiation induced mainly a dose-dependent increase of the preimplantation loss in the BALB/c strain and of the early postimplantation loss in the CF1 strain. Embryos of the BALB/c strain were refractory to the induction of teratogenic effects after such preimplantation irradiation. In CF1 mice, the frequency of malformed fetuses increased regularly after irradiation, the difference with controls being significant for the doses of 10, 50 and 100 cGy. Dwarfism occurrence also appeared to be increased by irradiation in this strain, although the importance of this effect varied depending on the criterion chosen for the assessment of dwarfs. With the definition proposed in the present paper, the increase in the frequency of dwarfs paralleled that of malformed fetuses, being significant after doses of 50 and 100 cGy. Irradiation did not increase the frequency of skeletal anomalies. A careful examination of the various data obtained to date led us to conclude that radiation may possibly be teratogenic in several mouse strains, when administered as early as during the one-cell stage and, to a lesser extent, during the following preimplantation stages. However, early prenatal mortality will remain by far the greatest risk associated with an exposure to radiation during this period. Moreover, the relativity of the risk of abnormality due to such irradiation should be considered in the context of the high prevalence of developmental defects spontaneously occurring during human pregnancy.

  17. Inhibitor of DNA binding 1 (Id1) induces differentiation and proliferation of mouse embryonic carcinoma P19CL6 cells

    International Nuclear Information System (INIS)

    Meng, Qingzhen; Jia, Zhuqing; Wang, Weiping; Li, Binhong; Ma, Kangtao; Zhou, Chunyan

    2011-01-01

    Highlights: → Id1 was upregulated during the cardiac differentiation process of P19CL6 cells. → Id1 upregulated expression of cardiac specific genes Gata4, α-MHC and ISL1. → Id1 promoted proliferation of P19CL6 cells. → Overexpression of Id1 increased activity of TOP flash. → Wnt3a or LiCl treatment promoted Id1 expression in P19CL6 cells. -- Abstract: The inhibitor of DNA binding (Id) family of genes encodes negative regulators of basic helix-loop-helix transcription factors and has been implicated in such diverse cellular processes as differentiation, proliferation, apoptosis and migration. Id knockout mouse embryos display multiple cardiac defects but the specific role of Id1 in cardiac differentiation is unclear. In the present study, we investigated the function of Id1 in DMSO-induced P19CL6 cells, a widely-accepted cell model of cardiac differentiation. We found that Id1 was upregulated during the cardiac differentiation of P19CL6 cells. The expression of cardiac specific marker genes, Gata4, α-MHC and ISL1, was upregulated in P19CL6 cells stably transfected with Id1 (P19CL6-Id1) during cardiac differentiation. The overexpression of Id1 reduced the number of cells in G1 phase and increased the cell population in G2, M and S phases, while knockdown of Id1 increased the number of cells in G1 phase from 48.6 ± 2.51% to 62.2 ± 1.52% at day 0 of cardiac induction, and from 52.5 ± 3.41% to 63.7 ± 1.02% at day 3 after cardiac induction, indicating that Id1 promoted proliferation of P19CL6 cells. Luciferase assays showed that the activity of TOP flash was higher in P19CL6-Id1 cells than wildtype P19CL6 cells, while Id1 expression was also upregulated in P19CL6 cells treated with Wnt3a or LiCl. This indicates that there may be positive feedback between Id1 and Wnt signaling which plays an important role in cardiac differentiation.

  18. The effect of caffeine on p53-dependent radioresponses in undifferentiated mouse embryonal carcinoma cells after X-ray and UV-irradiations

    International Nuclear Information System (INIS)

    Taga, Masataka; Shiraishi, Kazunori; Shimura, Tsutomu; Uematsu, Norio; Kato, Tomohisa; Niwa, Ohtsura; Nishimune, Yoshitake; Aizawa, Shinichi; Oshimura, Mitsuo

    2000-01-01

    The effect of caffeine was studied on the radioresponses of undifferentiated mouse embryonal carcinoma cells (EC cells) with or without the functional p53. The radioresponses studied included radiosensitivity, the activation of p53, apoptosis with characteristic DNA ladder formation and cell cycle progression. An undifferentiated mouse EC cell line, ECA2, and a newly established p53-deficient EC cell line, p53δ, were used in the present study. The status of the p53 gene did not significantly affect the colony survivals of undifferentiated EC cells to X-rays and UV. Although a post-irradiation treatment with caffeine sensitized both lines to X-rays marginally, the sensitization was prominent for UV regardless of the p53 status of the cells. The activation of a p53 responsible lacZ reporter construct was observed in stably transfected ECA2 cells after X-ray and UV irradiations. Caffeine suppressed the X-ray induced activation of the lacZ reporter, while it drastically enhanced the activation after UV irradiation. X-rays and UV readily triggered the apoptosis of ECA2 cells with the characteristic DNA ladder. Although UV-induced DNA ladder formation was enhanced by caffeine, that induced by X-rays was unaffected. Therefore, the effects of caffeine on the p53-dependent radioresponses were found to be agent specific: suppression for the X-ray induced and augmentation for the UV induced. In contrast to p53-proficient ECA2 cells, smear-like DNA degradation was observed for irradiated p53δ cells, suggesting the presence of a mode of cell death without DNA ladder formation. UV induction of the smear-like DNA degradation was enhanced in the presence of caffeine. Regardless of the state of the p53 gene, G1/S arrest was not observed in X-ray and UV irradiated EC cells. X-rays induced G2/M arrest in both lines, which was abrogated by caffeine, while G2/M arrest after UV was unaffected by a caffeine treatment. These results indicate that the radioresponses of undifferentiated

  19. The effect of caffeine on p53-dependent radioresponses in undifferentiated mouse embryonal carcinoma cells after X-ray and UV-irradiations

    Energy Technology Data Exchange (ETDEWEB)

    Taga, Masataka; Shiraishi, Kazunori; Shimura, Tsutomu; Uematsu, Norio; Kato, Tomohisa; Niwa, Ohtsura [Kyoto Univ. (Japan). Radiation Biology Center; Nishimune, Yoshitake; Aizawa, Shinichi; Oshimura, Mitsuo

    2000-09-01

    The effect of caffeine was studied on the radioresponses of undifferentiated mouse embryonal carcinoma cells (EC cells) with or without the functional p53. The radioresponses studied included radiosensitivity, the activation of p53, apoptosis with characteristic DNA ladder formation and cell cycle progression. An undifferentiated mouse EC cell line, ECA2, and a newly established p53-deficient EC cell line, p53{delta}, were used in the present study. The status of the p53 gene did not significantly affect the colony survivals of undifferentiated EC cells to X-rays and UV. Although a post-irradiation treatment with caffeine sensitized both lines to X-rays marginally, the sensitization was prominent for UV regardless of the p53 status of the cells. The activation of a p53 responsible lacZ reporter construct was observed in stably transfected ECA2 cells after X-ray and UV irradiations. Caffeine suppressed the X-ray induced activation of the lacZ reporter, while it drastically enhanced the activation after UV irradiation. X-rays and UV readily triggered the apoptosis of ECA2 cells with the characteristic DNA ladder. Although UV-induced DNA ladder formation was enhanced by caffeine, that induced by X-rays was unaffected. Therefore, the effects of caffeine on the p53-dependent radioresponses were found to be agent specific: suppression for the X-ray induced and augmentation for the UV induced. In contrast to p53-proficient ECA2 cells, smear-like DNA degradation was observed for irradiated p53{delta} cells, suggesting the presence of a mode of cell death without DNA ladder formation. UV induction of the smear-like DNA degradation was enhanced in the presence of caffeine. Regardless of the state of the p53 gene, G1/S arrest was not observed in X-ray and UV irradiated EC cells. X-rays induced G2/M arrest in both lines, which was abrogated by caffeine, while G2/M arrest after UV was unaffected by a caffeine treatment. These results indicate that the radioresponses of

  20. The mouse Gtl2 gene is differentially expressed during embryonic development, encodes multiple alternatively spliced transcripts, and may act as an RNA.

    Science.gov (United States)

    Schuster-Gossler, K; Bilinski, P; Sado, T; Ferguson-Smith, A; Gossler, A

    1998-06-01

    We have isolated a novel mouse gene (Gtl2) from the site of a gene trap integration (Gtl2lacZ) that gave rise to developmentally regulated lacZ expression, and a dominant parental-origin-dependent phenotype. Heterozygous Gtl2lacZ mice that inherited the transgene from the father showed a proportionate dwarfism phenotype, whereas the penetrance and expressivity of the phenotype was strongly reduced in Gtl2lacZ mice that inherited the transgene from the mother. Gtl2 expression is highly similar to the beta-galactosidase staining pattern, and is down-regulated but not abolished in mice carrying the Gtl2lacZ insertion. In early postimplantation embryos, Gtl2 is expressed in the visceral yolk sac and embryonic ectoderm. During subsequent development and organogenesis, Gtl2 transcripts are abundant in the paraxial mesoderm closely correlated with myogenic differentiation, in parts of the central nervous system, and in the epithelial ducts of developing excretory organs. The Gtl2 gene gives rise to various differentially spliced transcripts, which contain multiple small open reading frames (ORF). However, none of the ATG codons of these ORFs is in the context of a strong Kozak consensus sequence for initiation of translation, suggesting that Gtl2 might function as an RNA. Nuclear Gtl2 RNA was detected in a temporally and spatially regulated manner, and partially processed Gtl2 transcripts were readily detected in Northern blot hybridizations of polyadenylated RNA, suggesting that primary Gtl2 transcripts are differently processed in various cell types during development. Gtl2 transcript levels are present in parthenogenic embryos but may be reduced, consistent with the pattern of inheritance of the Gtl2lacZ phenotype.

  1. 3-O-sulfated heparan sulfate recognized by the antibody HS4C3 contributes [corrected] to the differentiation of mouse embryonic stem cells via fas signaling.

    Directory of Open Access Journals (Sweden)

    Kazumi Hirano

    Full Text Available Maintenance of self-renewal and pluripotency in mouse embryonic stem cells (mESCs is regulated by the balance between several extrinsic signaling pathways. Recently, we demonstrated that heparan sulfate (HS chains play important roles in the maintenance and differentiation of mESCs by regulating extrinsic signaling. Sulfated HS structures are modified by various sulfotransferases during development. However, the significance of specific HS structures during development remains unclear. Here, we show that 3-O-sulfated HS structures synthesized by HS 3-O-sulfotransferases (3OSTs and recognized by the antibody HS4C3 increase during differentiation of mESCs. Furthermore, expression of Fas on the cell surface of the differentiated cells also increased. Overexpression of the HS4C3-binding epitope in mESCs induced apoptosis and spontaneous differentiation even in the presence of LIF and serum. These data showed that the HS4C3-binding epitope was required for differentiation of mESCs. Up-regulation of the HS4C3-binding epitope resulted in the recruitment of Fas from the cytoplasm to lipid rafts on the cell surface followed by activation of Fas signaling. Indeed, the HS4C3-binding epitope interacted with a region that included the heparin-binding domain (KLRRRVH of Fas. Reduced self-renewal capability in cells overexpressing 3OST resulted from the degradation of Nanog by activated caspase-3, which is downstream of Fas signaling, and was rescued by the inhibition of Fas signaling. We also found that knockdown of 3OST and inhibition of Fas signaling reduced the potential for differentiation into the three germ layers during embryoid body formation. This is the first demonstration that activation of Fas signaling is mediated by an increase in the HS4C3-binding epitope and indicates a novel signaling pathway for differentiation in mESCs.

  2. 3-O-sulfated heparan sulfate recognized by the antibody HS4C3 contributes [corrected] to the differentiation of mouse embryonic stem cells via fas signaling.

    Science.gov (United States)

    Hirano, Kazumi; Sasaki, Norihiko; Ichimiya, Tomomi; Miura, Taichi; Van Kuppevelt, Toin H; Nishihara, Shoko

    2012-01-01

    Maintenance of self-renewal and pluripotency in mouse embryonic stem cells (mESCs) is regulated by the balance between several extrinsic signaling pathways. Recently, we demonstrated that heparan sulfate (HS) chains play important roles in the maintenance and differentiation of mESCs by regulating extrinsic signaling. Sulfated HS structures are modified by various sulfotransferases during development. However, the significance of specific HS structures during development remains unclear. Here, we show that 3-O-sulfated HS structures synthesized by HS 3-O-sulfotransferases (3OSTs) and recognized by the antibody HS4C3 increase during differentiation of mESCs. Furthermore, expression of Fas on the cell surface of the differentiated cells also increased. Overexpression of the HS4C3-binding epitope in mESCs induced apoptosis and spontaneous differentiation even in the presence of LIF and serum. These data showed that the HS4C3-binding epitope was required for differentiation of mESCs. Up-regulation of the HS4C3-binding epitope resulted in the recruitment of Fas from the cytoplasm to lipid rafts on the cell surface followed by activation of Fas signaling. Indeed, the HS4C3-binding epitope interacted with a region that included the heparin-binding domain (KLRRRVH) of Fas. Reduced self-renewal capability in cells overexpressing 3OST resulted from the degradation of Nanog by activated caspase-3, which is downstream of Fas signaling, and was rescued by the inhibition of Fas signaling. We also found that knockdown of 3OST and inhibition of Fas signaling reduced the potential for differentiation into the three germ layers during embryoid body formation. This is the first demonstration that activation of Fas signaling is mediated by an increase in the HS4C3-binding epitope and indicates a novel signaling pathway for differentiation in mESCs.

  3. CHIR99021 promotes self-renewal of mouse embryonic stem cells by modulation of protein-encoding gene and long intergenic non-coding RNA expression

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Yongyan [College of Veterinary Medicine, Northwest A and F University, Yangling 712100, Shaanxi (China); Key Laboratory of Animal Biotechnology, Ministry of Agriculture, Northwest A and F University, Yangling 712100, Shaanxi (China); Ai, Zhiying [Key Laboratory of Animal Biotechnology, Ministry of Agriculture, Northwest A and F University, Yangling 712100, Shaanxi (China); College of Life Sciences, Northwest A and F University, Yangling 712100, Shaanxi (China); Yao, Kezhen [College of Veterinary Medicine, Northwest A and F University, Yangling 712100, Shaanxi (China); Key Laboratory of Animal Biotechnology, Ministry of Agriculture, Northwest A and F University, Yangling 712100, Shaanxi (China); Cao, Lixia; Du, Juan; Shi, Xiaoyan [Key Laboratory of Animal Biotechnology, Ministry of Agriculture, Northwest A and F University, Yangling 712100, Shaanxi (China); College of Life Sciences, Northwest A and F University, Yangling 712100, Shaanxi (China); Guo, Zekun, E-mail: gzk@nwsuaf.edu.cn [College of Veterinary Medicine, Northwest A and F University, Yangling 712100, Shaanxi (China); Key Laboratory of Animal Biotechnology, Ministry of Agriculture, Northwest A and F University, Yangling 712100, Shaanxi (China); Zhang, Yong, E-mail: zhylab@hotmail.com [College of Veterinary Medicine, Northwest A and F University, Yangling 712100, Shaanxi (China); Key Laboratory of Animal Biotechnology, Ministry of Agriculture, Northwest A and F University, Yangling 712100, Shaanxi (China)

    2013-10-15

    Embryonic stem cells (ESCs) can proliferate indefinitely in vitro and differentiate into cells of all three germ layers. These unique properties make them exceptionally valuable for drug discovery and regenerative medicine. However, the practical application of ESCs is limited because it is difficult to derive and culture ESCs. It has been demonstrated that CHIR99021 (CHIR) promotes self-renewal and enhances the derivation efficiency of mouse (m)ESCs. However, the downstream targets of CHIR are not fully understood. In this study, we identified CHIR-regulated genes in mESCs using microarray analysis. Our microarray data demonstrated that CHIR not only influenced the Wnt/β-catenin pathway by stabilizing β-catenin, but also modulated several other pluripotency-related signaling pathways such as TGF-β, Notch and MAPK signaling pathways. More detailed analysis demonstrated that CHIR inhibited Nodal signaling, while activating bone morphogenetic protein signaling in mESCs. In addition, we found that pluripotency-maintaining transcription factors were up-regulated by CHIR, while several developmental-related genes were down-regulated. Furthermore, we found that CHIR altered the expression of epigenetic regulatory genes and long intergenic non-coding RNAs. Quantitative real-time PCR results were consistent with microarray data, suggesting that CHIR alters the expression pattern of protein-encoding genes (especially transcription factors), epigenetic regulatory genes and non-coding RNAs to establish a relatively stable pluripotency-maintaining network. - Highlights: • Combined use of CHIR with LIF promotes self-renewal of J1 mESCs. • CHIR-regulated genes are involved in multiple pathways. • CHIR inhibits Nodal signaling and promotes Bmp4 expression to activate BMP signaling. • Expression of epigenetic regulatory genes and lincRNAs is altered by CHIR.

  4. CHIR99021 promotes self-renewal of mouse embryonic stem cells by modulation of protein-encoding gene and long intergenic non-coding RNA expression

    International Nuclear Information System (INIS)

    Wu, Yongyan; Ai, Zhiying; Yao, Kezhen; Cao, Lixia; Du, Juan; Shi, Xiaoyan; Guo, Zekun; Zhang, Yong

    2013-01-01

    Embryonic stem cells (ESCs) can proliferate indefinitely in vitro and differentiate into cells of all three germ layers. These unique properties make them exceptionally valuable for drug discovery and regenerative medicine. However, the practical application of ESCs is limited because it is difficult to derive and culture ESCs. It has been demonstrated that CHIR99021 (CHIR) promotes self-renewal and enhances the derivation efficiency of mouse (m)ESCs. However, the downstream targets of CHIR are not fully understood. In this study, we identified CHIR-regulated genes in mESCs using microarray analysis. Our microarray data demonstrated that CHIR not only influenced the Wnt/β-catenin pathway by stabilizing β-catenin, but also modulated several other pluripotency-related signaling pathways such as TGF-β, Notch and MAPK signaling pathways. More detailed analysis demonstrated that CHIR inhibited Nodal signaling, while activating bone morphogenetic protein signaling in mESCs. In addition, we found that pluripotency-maintaining transcription factors were up-regulated by CHIR, while several developmental-related genes were down-regulated. Furthermore, we found that CHIR altered the expression of epigenetic regulatory genes and long intergenic non-coding RNAs. Quantitative real-time PCR results were consistent with microarray data, suggesting that CHIR alters the expression pattern of protein-encoding genes (especially transcription factors), epigenetic regulatory genes and non-coding RNAs to establish a relatively stable pluripotency-maintaining network. - Highlights: • Combined use of CHIR with LIF promotes self-renewal of J1 mESCs. • CHIR-regulated genes are involved in multiple pathways. • CHIR inhibits Nodal signaling and promotes Bmp4 expression to activate BMP signaling. • Expression of epigenetic regulatory genes and lincRNAs is altered by CHIR

  5. Molecular functions of the LIM-homeobox transcription factor Lhx2 in hematopoietic progenitor cells derived from mouse embryonic stem cells.

    Science.gov (United States)

    Kitajima, Kenji; Kawaguchi, Manami; Iacovino, Michelina; Kyba, Michael; Hara, Takahiko

    2013-12-01

    We previously demonstrated that hematopoietic stem cell (HSC)-like cells are robustly expanded from mouse embryonic stem cells (ESCs) by enforced expression of Lhx2, a LIM-homeobox domain (LIM-HD) transcription factor. In this study, we analyzed the functions of Lhx2 in that process using an ESC line harboring an inducible Lhx2 gene cassette. When ESCs are cultured on OP9 stromal cells, hematopoietic progenitor cells (HPCs) are differentiated and these HPCs are prone to undergo rapid differentiation into mature hematopoietic cells. Lhx2 inhibited differentiation of HPCs into mature hematopoietic cells and this effect would lead to accumulation of HSC-like cells. LIM-HD factors interact with LIM domain binding (Ldb) protein and this interaction abrogates binding of LIM-only (Lmo) protein to Ldb. We found that one of Lmo protein, Lmo2, was unstable due to dissociation of Lmo2 from Ldb1 in the presence of Lhx2. This effect of Lhx2 on the amount of Lmo2 contributed into accumulation of HSC-like cells, since enforced expression of Lmo2 into HSC-like cells inhibited their self-renewal. Expression of Gata3 and Tal1/Scl was increased in HSC-like cells and enforced expression of Lmo2 reduced expression of Gata3 but not Tal1/Scl. Enforced expression of Gata3 into HPCs inhibited mature hematopoietic cell differentiation, whereas Gata3-knockdown abrogated the Lhx2-mediated expansion of HPCs. We propose that multiple transcription factors/cofactors are involved in the Lhx2-mediated expansion of HSC-like cells from ESCs. Lhx2 appears to fine-tune the balance between self-renewal and differentiation of HSC-like cells. © AlphaMed Press.

  6. Dual expression of Epstein-Barr virus, latent membrane protein-1 and human papillomavirus-16 E6 transform primary mouse embryonic fibroblasts through NF-κB signaling.

    Science.gov (United States)

    Shimabuku, Tetsuya; Tamanaha, Ayumi; Kitamura, Bunta; Tanabe, Yasuka; Tawata, Natsumi; Ikehara, Fukino; Arakaki, Kazunari; Kinjo, Takao

    2014-01-01

    The prevalence of Epstein-Barr virus (EBV) and high-risk human papilloma virus (HPV) infections in patients with oral cancer in Okinawa, southwest islands of Japan, has led to the hypothesis that carcinogenesis is related to EBV and HPV co-infection. To explore the mechanisms of transformation induced by EBV and HPV co-infection, we analyzed the transformation of primary mouse embryonic fibroblasts (MEFs) expressing EBV and HPV-16 genes, alone or in combination. Expression of EBV latent membrane protein-1 (LMP-1) alone or in combination with HPV-16 E6 increased cell proliferation and decreased apoptosis, whereas single expression of EBV nuclear antigen-1 (EBNA-1), or HPV-16 E6 did not. Co-expression of LMP-1 and E6 induced anchorage-independent growth and tumor formation in nude mice, whereas expression of LMP-1 alone did not. Although the singular expression of these viral genes showed increased DNA damage and DNA damage response (DDR), co-expression of LMP-1 and E6 did not induce DDR, which is frequently seen in cancer cells. Furthermore, co-expression of LMP-1 with E6 increased NF-κB signaling, and the knockdown of LMP-1 or E6 in co-expressing cells decreased cell proliferation, anchorage independent growth, and NF-κB activation. These data suggested that expression of individual viral genes is insufficient for inducing transformation and that co-expression of LMP-1 and E6, which is associated with suppression of DDR and increased NF-κB activity, lead to transformation. Our findings demonstrate the synergistic effect by the interaction of oncogenes from different viruses on the transformation of primary MEFs.

  7. Disconnect between alcohol-induced alterations in chromatin structure and gene transcription in a mouse embryonic stem cell model of exposure.

    Science.gov (United States)

    Veazey, Kylee J; Wang, Haiqing; Bedi, Yudhishtar S; Skiles, William M; Chang, Richard Cheng-An; Golding, Michael C

    2017-05-01

    Alterations to chromatin structure induced by environmental insults have become an attractive explanation for the persistence of exposure effects into subsequent life stages. However, a growing body of work examining the epigenetic impact that alcohol and other drugs of abuse exert consistently notes a disconnection between induced changes in chromatin structure and patterns of gene transcription. Thus, an important question is whether perturbations in the 'histone code' induced by prenatal exposures to alcohol implicitly subvert gene expression, or whether the hierarchy of cellular signaling networks driving development is such that they retain control over the transcriptional program. To address this question, we examined the impact of ethanol exposure in mouse embryonic stem cells cultured under 2i conditions, where the transcriptional program is rigidly enforced through the use of small molecule inhibitors. We find that ethanol-induced changes in post-translational histone modifications are dose-dependent, unique to the chromatin modification under investigation, and that the extent and direction of the change differ between the period of exposure and the recovery phase. Similar to in vivo models, we find post-translational modifications affecting histone 3 lysine 9 are the most profoundly impacted, with the signature of exposure persisting long after alcohol has been removed. These changes in chromatin structure associate with dose-dependent alterations in the levels of transcripts encoding Dnmt1, Uhrf1, Tet1, Tet2, Tet3, and Polycomb complex members Eed and Ezh2. However, in this model, ethanol-induced changes to the chromatin template do not consistently associate with changes in gene transcription, impede the process of differentiation, or affect the acquisition of monoallelic patterns of expression for the imprinted gene Igf2R. These findings question the inferred universal relevance of epigenetic changes induced by drugs of abuse and suggest that changes

  8. Phosphatase Inhibitors Function as Novel, Broad Spectrum Botulinum Neurotoxin Antagonists in Mouse and Human Embryonic Stem Cell-Derived Motor Neuron-Based Assays.

    Directory of Open Access Journals (Sweden)

    Erkan Kiris

    Full Text Available There is an urgent need to develop novel treatments to counter Botulinum neurotoxin (BoNT poisoning. Currently, the majority of BoNT drug development efforts focus on directly inhibiting the proteolytic components of BoNT, i.e. light chains (LC. Although this is a rational approach, previous research has shown that LCs are extremely difficult drug targets and that inhibiting multi-serotype BoNTs with a single LC inhibitor may not be feasible. An alternative approach would target neuronal pathways involved in intoxication/recovery, rather than the LC itself. Phosphorylation-related mechanisms have been implicated in the intoxication pathway(s of BoNTs. However, the effects of phosphatase inhibitors upon BoNT activity in the physiological target of BoNTs, i.e. motor neurons, have not been investigated. In this study, a small library of phosphatase inhibitors was screened for BoNT antagonism in the context of mouse embryonic stem cell-derived motor neurons (ES-MNs. Four inhibitors were found to function as BoNT/A antagonists. Subsequently, we confirmed that these inhibitors protect against BoNT/A in a dose-dependent manner in human ES-MNs. Additionally, these compounds provide protection when administered in post-intoxication scenario. Importantly, the inhibitors were also effective against BoNT serotypes B and E. To the best of our knowledge, this is the first study showing phosphatase inhibitors as broad-spectrum BoNT antagonists.

  9. Inhibitory Interneurons of The Human Neocortex after Clinical Death

    Directory of Open Access Journals (Sweden)

    V. A. Akulinin

    2016-01-01

    Full Text Available Objective: to analyze the human neocortex interneurons (areas 4, 10, 17 and 21 by Brodmann after cardiac arrest (clinical death.Materials and methods. The main group included patients (n=7, men who survived 7—10 days and 70—90 days after cardiac arrest and later died due to heart failure. The control group (n=4, men included individuals after sudden fatal accidents. The morphometric and histological analysis of 420 neocortical fields (Nissl#staining,calbindin D28k, neuropeptide Y was performed using light and confocal microscopy.Results. We verified all main types of interneurons (Basket, Martinotti, and neurogliaform interneurons in neocortex based on the morphology of their bodies and dendritic processes in both groups. The number of calbindin- and NPY-positive neurons in the neocortex was similar in the control and in the postoperative period.However, calbindin- and NPY-immunopositive structure fields including neuronal cell bodies and their dendrites were significantly more represented in neocortex of patients from the main group. Maximum increase in common square in the relative areas of calbindin-immunopositive structures was observed 90 days after ischemia. The squares of NPY#immunopositive fields became larger seven days after resuscitation and remained increased on 90th day post-resuscitation.Conclusion. Our findings demonstrate an increase of calbindin and NPY expression in human neocortex after clinical death, which can be explained by a compensatory  eaction of undamaged inhibitory cortical interneurons directed to protectbrain from ischemia.

  10. mGluR5 stimulating Homer–PIKE formation initiates icariin induced cardiomyogenesis of mouse embryonic stem cells by activating reactive oxygen species

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Limin; Huang, Yujie; Zhang, Yingying [Institute of Pharmacology, Toxicology and Biochemical Pharmaceutics, College of Pharmaceutical Sciences, Zhejiang University, No. 866, Yu Hang Tang Road, Hangzhou 310058 (China); Zhao, Qingwei [The First Affiliated Hospital, College of Medicine, Zhejiang University, No. 79, Qing Chun Road, Hangzhou 310003 (China); Zheng, Bei; Lou, Yijia [Institute of Pharmacology, Toxicology and Biochemical Pharmaceutics, College of Pharmaceutical Sciences, Zhejiang University, No. 866, Yu Hang Tang Road, Hangzhou 310058 (China); Zhu, Danyan, E-mail: zdyzxb@zju.edu.cn [Institute of Pharmacology, Toxicology and Biochemical Pharmaceutics, College of Pharmaceutical Sciences, Zhejiang University, No. 866, Yu Hang Tang Road, Hangzhou 310058 (China)

    2013-06-10

    Icariin (ICA) has been reported to facilitate cardiac differentiation of mouse embryonic stem (ES) cells; however, the mechanism by which ICA induced cardiomyogenesis has not been fully elucidated yet. Here, an underlying signaling network including metabotropic glutamate receptor 5 (mGluR5), Homer, phosphatidylinositol 3-Kinase Enhancer (PIKE), phosphatidylinositol 3-Kinase (PI3K), reactive oxygen species (ROS) and nuclear factor-kappaB (NF-κB) was investigated in ICA induced cardiomyogenesis. Our results showed that the co-expression of mGluR5 together with α-actinin or Troponin T in embryoid bodies (EBs) treated with ICA was elevated to 10.86% and 9.62%, compared with the case in the control (4.04% and 3.45%, respectively). Exposure of EBs to ICA for 2 h remarkably increased the dimeric form of mGluR5, which was inhibited by small interfering RNA targeting mGluR5 (si-mGluR5). Moreover, the extracellular glutamate concentration in ICA treatment medium was elevated to 28.9±3.5 μM. Furthermore, the activation of mGluR5 by ICA triggered the formation of Homer–PIKE complex and activated PI3K, stimulating ROS generation and NF-κB nuclear translocation. Knockdown of mGluR5 or inhibition of PI3K by LY294002 blocked ICA induced cardiomyogenesis via repressing mGluR5 pathway, reducing ROS and NF-κB activation. These results revealed that the inducible mechanisms of ICA were related to activate mGluR5 pathway. -- Highlights: • ICA increased mGluR5 expression in cardiac differentiation of ES cells. • ICA enhanced the glutamate level and the receptor mGluR5 dimerization, stimulating the formation of Homer–PIKE complex. • Knockdown of mGluR5 or inhibition of PI3K by LY294002 inhibited ICA induced ROS generation and NF-κB nuclear translocation.

  11. MicroRNA transcriptome analysis identifies miR-365 as a novel negative regulator of cell proliferation in Zmpste24-deficient mouse embryonic fibroblasts

    International Nuclear Information System (INIS)

    Xiong, Xing-dong; Jung, Hwa Jin; Gombar, Saurabh; Park, Jung Yoon; Zhang, Chun-long; Zheng, Huiling; Ruan, Jie; Li, Jiang-bin; Kaeberlein, Matt

    2015-01-01

    Highlights: • A comprehensive miRNA transcriptome of MEFs from Zmpste24 −/− and control mice. • Identification of miR-365 as a down-regulated miRNA in Zmpste24 −/− MEFs. • Characterization of miR-365 as a modulator of cellular growth in part by targeting Rasd1. - Abstract: Zmpste24 is a metalloproteinase responsible for the posttranslational processing and cleavage of prelamin A into mature laminA. Zmpste24 −/− mice display a range of progeroid phenotypes overlapping with mice expressing progerin, an altered version of lamin A associated with Hutchinson-Gilford progeria syndrome (HGPS). Increasing evidence has demonstrated that miRNAs contribute to the regulation of normal aging process, but their roles in progeroid disorders remain poorly understood. Here we report the miRNA transcriptomes of mouse embryonic fibroblasts (MEFs) established from wild type (WT) and Zmpste24 −/− progeroid mice using a massively parallel sequencing technology. With data from 19.5 × 10 6 reads from WT MEFs and 16.5 × 10 6 reads from Zmpste24 −/− MEFs, we discovered a total of 306 known miRNAs expressed in MEFs with a wide dynamic range of read counts ranging from 10 to over 1 million. A total of 8 miRNAs were found to be significantly down-regulated, with only 2 miRNAs upregulated, in Zmpste24 −/− MEFs as compared to WT MEFs. Functional studies revealed that miR-365, a significantly down-regulated miRNA in Zmpste24 −/− MEFs, modulates cellular growth phenotypes in MEFs. Overexpression of miR-365 in Zmpste24 −/− MEFs increased cellular proliferation and decreased the percentage of SA-β-gal-positive cells, while inhibition of miR-365 function led to an increase of SA-β-gal-positive cells in WT MEFs. Furthermore, we identified Rasd1, a member of the Ras superfamily of small GTPases, as a functional target of miR-365. While expression of miR-365 suppressed Rasd1 3′ UTR luciferase-reporter activity, this effect was lost with mutations in the

  12. Piper betle induces phase I & II genes through Nrf2/ARE signaling pathway in mouse embryonic fibroblasts derived from wild type and Nrf2 knockout cells.

    Science.gov (United States)

    Wan Hasan, Wan Nuraini; Kwak, Mi-Kyoung; Makpol, Suzana; Wan Ngah, Wan Zurinah; Mohd Yusof, Yasmin Anum

    2014-02-23

    Nuclear factor-erythroid 2 p45 related factor 2 (Nrf2) is a primary transcription factor, protecting cells from oxidative stress by regulating a number of antioxidants and phase II detoxifying enzymes. Dietary components such as sulforaphane in broccoli and quercetin in onions have been shown to be inducers of Nrf2. Piper betle (PB) grows well in tropical climate and the leaves are used in a number of traditional remedies for the treatment of stomach ailments and infections among Asians. The aim of this study was to elucidate the effect of Piper betle (PB) leaves extract in Nrf2 signaling pathway by using 2 types of cells; mouse embryonic fibroblasts (MEFs) derived from wild-type (WT) and Nrf2 knockout (N0) mice. WT and N0 cells were treated with 5 and 10 μg/ml of PB for 10 and 12-h for the determination of nuclear translocation of Nrf2 protein. Luciferase reporter gene activity was performed to evaluate the antioxidant response element (ARE)-induction by PB. Real-time PCR and Western blot were conducted on both WT and N0 cells after PB treatment for the determination of antioxidant enzymes [superoxide dismutase (SOD1) and heme-oxygenase (HO-1)], phase I oxidoreductase enzymes [ quinone oxidoreductase (NQO1)] and phase II detoxifying enzyme [glutathione S-transferase (GST)]. Nuclear translocation of Nrf2 by PB in WT cells was better after 10 h incubation compared to 12 h. Real time PCR and Western blot analysis showed increased expressions of Nrf2, NQO1 and GSTA1 genes with corresponding increases in glutathione, NQO1 and HO-1 proteins in WT cells. Reporter gene ARE was stimulated by PB as shown by ARE/luciferase assay. Interestingly, PB induced SOD1 gene and protein expressions in N0 cells but not in WT cells. The results of this study confirmed that PB activated Nrf2-ARE signaling pathway which subsequently induced some phase I oxidoreductase, phase II detoxifying and antioxidant genes expression via ARE reporter gene involved in the Nrf2 pathway with the

  13. Choline acetyltransferase-containing neurons in the human parietal neocortex

    Directory of Open Access Journals (Sweden)

    V Benagiano

    2009-06-01

    Full Text Available A number of immunocytochemical studies have indicated the presence of cholinergic neurons in the cerebral cortex of various species of mammals. Whether such cholinergic neurons in the human cerebral cortex are exclusively of subcortical origin is still debated. In this immunocytochemical study, the existence of cortical cholinergic neurons was investigated on surgical samples of human parietal association neocortex using a highly specific monoclonal antibody against choline acetyltransferase (ChAT, the acetylcholine biosynthesising enzyme. ChAT immunoreactivity was detected in a subpopulation of neurons located in layers II and III. These were small or medium-sized pyramidal neurons which showed cytoplasmic immunoreactivity in the perikarya and processes, often in close association to blood microvessels. This study, providing demonstration of ChAT neurons in the human parietal neocortex, strongly supports the existence of intrinsic cholinergic innervation of the human neocortex. It is likely that these neurons contribute to the cholinergic innervation of the intracortical microvessels.

  14. Effects of network resolution on topological properties of human neocortex

    DEFF Research Database (Denmark)

    Romero-Garcia, Rafael; Atienza, Mercedes; Clemmensen, Line Katrine Harder

    2012-01-01

    Graph theoretical analyses applied to neuroimaging datasets have provided valuable insights into the large-scale anatomical organization of the human neocortex. Most of these studies were performed with different cortical scales leading to cortical networks with different levels of small-world or......Graph theoretical analyses applied to neuroimaging datasets have provided valuable insights into the large-scale anatomical organization of the human neocortex. Most of these studies were performed with different cortical scales leading to cortical networks with different levels of small...

  15. Combined serial analysis of gene expression and transcription factor binding site prediction identifies novel-candidate-target genes of Nr2e1 in neocortex development.

    Science.gov (United States)

    Schmouth, Jean-François; Arenillas, David; Corso-Díaz, Ximena; Xie, Yuan-Yun; Bohacec, Slavita; Banks, Kathleen G; Bonaguro, Russell J; Wong, Siaw H; Jones, Steven J M; Marra, Marco A; Simpson, Elizabeth M; Wasserman, Wyeth W

    2015-07-24

    Nr2e1 (nuclear receptor subfamily 2, group e, member 1) encodes a transcription factor important in neocortex development. Previous work has shown that nuclear receptors can have hundreds of target genes, and bind more than 300 co-interacting proteins. However, recognition of the critical role of Nr2e1 in neural stem cells and neocortex development is relatively recent, thus the molecular mechanisms involved for this nuclear receptor are only beginning to be understood. Serial analysis of gene expression (SAGE), has given researchers both qualitative and quantitative information pertaining to biological processes. Thus, in this work, six LongSAGE mouse libraries were generated from laser microdissected tissue samples of dorsal VZ/SVZ (ventricular zone and subventricular zone) from the telencephalon of wild-type (Wt) and Nr2e1-null embryos at the critical development ages E13.5, E15.5, and E17.5. We then used a novel approach, implementing multiple computational methods followed by biological validation to further our understanding of Nr2e1 in neocortex development. In this work, we have generated a list of 1279 genes that are differentially expressed in response to altered Nr2e1 expression during in vivo neocortex development. We have refined this list to 64 candidate direct-targets of NR2E1. Our data suggested distinct roles for Nr2e1 during different neocortex developmental stages. Most importantly, our results suggest a possible novel pathway by which Nr2e1 regulates neurogenesis, which includes Lhx2 as one of the candidate direct-target genes, and SOX9 as a co-interactor. In conclusion, we have provided new candidate interacting partners and numerous well-developed testable hypotheses for understanding the pathways by which Nr2e1 functions to regulate neocortex development.

  16. Sleep-dependent directional coupling between human neocortex and hippocampus.

    Science.gov (United States)

    Wagner, Tobias; Axmacher, Nikolai; Lehnertz, Klaus; Elger, Christian E; Fell, Jürgen

    2010-02-01

    Complex interactions between neocortex and hippocampus are the neural basis of memory formation. Two-step theories of memory formation suggest that initial encoding of novel information depends on the induction of rapid plasticity within the hippocampus, and is followed by a second sleep-dependent step of memory consolidation. These theories predict information flow from the neocortex into the hippocampus during waking state and in the reverse direction during sleep. However, experimental evidence that interactions between hippocampus and neocortex have a predominant direction which reverses during sleep rely on cross-correlation analysis of data from animal experiments and yielded inconsistent results. Here, we investigated directional coupling in intracranial EEG data from human subjects using a phase-modeling approach which is well suited to reveal functional interdependencies in oscillatory data. In general, we observed that the anterior hippocampus predominantly drives nearby and remote brain regions. Surprisingly, however, the influence of neocortical regions on the hippocampus significantly increased during sleep as compared to waking state. These results question the standard model of hippocampal-neocortical interactions and suggest that sleep-dependent consolidation is accomplished by an active retrieval of hippocampal information by the neocortex. Copyright 2009 Elsevier Srl. All rights reserved.

  17. BIG1 is required for the survival of deep layer neurons, neuronal polarity, and the formation of axonal tracts between the thalamus and neocortex in developing brain.

    Directory of Open Access Journals (Sweden)

    Jia-Jie Teoh

    Full Text Available BIG1, an activator protein of the small GTPase, Arf, and encoded by the Arfgef1 gene, is one of candidate genes for epileptic encephalopathy. To know the involvement of BIG1 in epileptic encephalopathy, we analyzed BIG1-deficient mice and found that BIG1 regulates neurite outgrowth and brain development in vitro and in vivo. The loss of BIG1 decreased the size of the neocortex and hippocampus. In BIG1-deficient mice, the neuronal progenitor cells (NPCs and the interneurons were unaffected. However, Tbr1+ and Ctip2+ deep layer (DL neurons showed spatial-temporal dependent apoptosis. This apoptosis gradually progressed from the piriform cortex (PIR, peaked in the neocortex, and then progressed into the hippocampus from embryonic day 13.5 (E13.5 to E17.5. The upper layer (UL and DL order in the neocortex was maintained in BIG1-deficient mice, but the excitatory neurons tended to accumulate before their destination layers. Further pulse-chase migration assay showed that the migration defect was non-cell autonomous and secondary to the progression of apoptosis into the BIG1-deficient neocortex after E15.5. In BIG1-deficient mice, we observed an ectopic projection of corticothalamic axons from the primary somatosensory cortex (S1 into the dorsal lateral geniculate nucleus (dLGN. The thalamocortical axons were unable to cross the diencephalon-telencephalon boundary (DTB. In vitro, BIG1-deficient neurons showed a delay in neuronal polarization. BIG1-deficient neurons were also hypersensitive to low dose glutamate (5 μM, and died via apoptosis. This study showed the role of BIG1 in the survival of DL neurons in developing embryonic brain and in the generation of neuronal polarity.

  18. MicroRNA transcriptome analysis identifies miR-365 as a novel negative regulator of cell proliferation in Zmpste24-deficient mouse embryonic fibroblasts

    Energy Technology Data Exchange (ETDEWEB)

    Xiong, Xing-dong [Institute of Aging Research, Guangdong Medical College, Xin Cheng Avenue 1#, Songshan Lake, Dongguan, Guangdong 523808 (China); Institute of Biochemistry & Molecular Biology, Guangdong Medical College, Zhanjiang 524023 (China); Key Laboratory for Medical Molecular Diagnostics of Guangdong Province, Dongguan 523808 (China); Institute of Laboratory Medicine, Guangdong Medical College, Dongguan, Guangdong 523808 (China); Jung, Hwa Jin [Departments of Genetics, Albert Einstein College of Medicine, Bronx, NY 10461 (United States); Gombar, Saurabh [Departments of Systems Biology, Albert Einstein College of Medicine, Bronx, NY 10461 (United States); Park, Jung Yoon [Departments of Genetics, Albert Einstein College of Medicine, Bronx, NY 10461 (United States); Zhang, Chun-long; Zheng, Huiling [Institute of Aging Research, Guangdong Medical College, Xin Cheng Avenue 1#, Songshan Lake, Dongguan, Guangdong 523808 (China); Institute of Biochemistry & Molecular Biology, Guangdong Medical College, Zhanjiang 524023 (China); Key Laboratory for Medical Molecular Diagnostics of Guangdong Province, Dongguan 523808 (China); Ruan, Jie; Li, Jiang-bin [Institute of Aging Research, Guangdong Medical College, Xin Cheng Avenue 1#, Songshan Lake, Dongguan, Guangdong 523808 (China); Institute of Biochemistry & Molecular Biology, Guangdong Medical College, Zhanjiang 524023 (China); Key Laboratory for Medical Molecular Diagnostics of Guangdong Province, Dongguan 523808 (China); Institute of Laboratory Medicine, Guangdong Medical College, Dongguan, Guangdong 523808 (China); Kaeberlein, Matt [Institute of Aging Research, Guangdong Medical College, Xin Cheng Avenue 1#, Songshan Lake, Dongguan, Guangdong 523808 (China); Department of Pathology, University of Washington, Seattle, WA 98195 (United States); and others

    2015-07-15

    Highlights: • A comprehensive miRNA transcriptome of MEFs from Zmpste24{sup −/−} and control mice. • Identification of miR-365 as a down-regulated miRNA in Zmpste24{sup −/−} MEFs. • Characterization of miR-365 as a modulator of cellular growth in part by targeting Rasd1. - Abstract: Zmpste24 is a metalloproteinase responsible for the posttranslational processing and cleavage of prelamin A into mature laminA. Zmpste24{sup −/−} mice display a range of progeroid phenotypes overlapping with mice expressing progerin, an altered version of lamin A associated with Hutchinson-Gilford progeria syndrome (HGPS). Increasing evidence has demonstrated that miRNAs contribute to the regulation of normal aging process, but their roles in progeroid disorders remain poorly understood. Here we report the miRNA transcriptomes of mouse embryonic fibroblasts (MEFs) established from wild type (WT) and Zmpste24{sup −/−} progeroid mice using a massively parallel sequencing technology. With data from 19.5 × 10{sup 6} reads from WT MEFs and 16.5 × 10{sup 6} reads from Zmpste24{sup −/−} MEFs, we discovered a total of 306 known miRNAs expressed in MEFs with a wide dynamic range of read counts ranging from 10 to over 1 million. A total of 8 miRNAs were found to be significantly down-regulated, with only 2 miRNAs upregulated, in Zmpste24{sup −/−} MEFs as compared to WT MEFs. Functional studies revealed that miR-365, a significantly down-regulated miRNA in Zmpste24{sup −/−} MEFs, modulates cellular growth phenotypes in MEFs. Overexpression of miR-365 in Zmpste24{sup −/−} MEFs increased cellular proliferation and decreased the percentage of SA-β-gal-positive cells, while inhibition of miR-365 function led to an increase of SA-β-gal-positive cells in WT MEFs. Furthermore, we identified Rasd1, a member of the Ras superfamily of small GTPases, as a functional target of miR-365. While expression of miR-365 suppressed Rasd1 3′ UTR luciferase-reporter activity

  19. Mouse adhalin

    DEFF Research Database (Denmark)

    Liu, L; Vachon, P H; Kuang, W

    1997-01-01

    . To analyze the biological roles of adhalin, we cloned the mouse adhalin cDNA, raised peptide-specific antibodies to its cytoplasmic domain, and examined its expression and localization in vivo and in vitro. The mouse adhalin sequence was 80% identical to that of human, rabbit, and hamster. Adhalin...... was specifically expressed in striated muscle cells and their immediate precursors, and absent in many other cell types. Adhalin expression in embryonic mouse muscle was coincident with primary myogenesis. Its expression was found to be up-regulated at mRNA and protein levels during myogenic differentiation...

  20. Genetic Tools for Self-Organizing Culture of Mouse Embryonic Stem Cells via Small Regulatory RNA-Mediated Technologies, CRISPR/Cas9, and Inducible RNAi.

    Science.gov (United States)

    Takata, Nozomu; Sakakura, Eriko; Sakuma, Tetsushi; Yamamoto, Takashi

    2017-01-01

    Approaches to investigate gene functions in experimental biology are becoming more diverse and reliable. Furthermore, several kinds of tissues and organs that possess their original identities can be generated in petri dishes from stem cells including embryonic, adult and induced pluripotent stem cells. Researchers now have several choices of experimental methods and their combinations to analyze gene functions in various biological systems. Here, as an example we describe one of the better protocols, which combines three-dimensional embryonic stem cell culture with small regulatory RNA-mediated technologies, clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9), and inducible RNA interference (RNAi). This protocol allows investigation of genes of interest to better understand gene functions in target tissues (or organs) during in vitro development.

  1. Chemical composition of the essential oil from basil (Ocimum basilicum Linn.) and its in vitro cytotoxicity against HeLa and HEp-2 human cancer cell lines and NIH 3T3 mouse embryonic fibroblasts.

    Science.gov (United States)

    Kathirvel, Poonkodi; Ravi, Subban

    2012-01-01

    This study examines the chemical composition and in vitro anticancer activity of the essential oil from Ocimum basilicum Linn. (Lamiaceae), cultivated in the Western Ghats of South India. The chemical compositions of basil fresh leaves were identified by GC-MS: 11 components were identified. The major constituents were found to be methyl cinnamate (70.1%), linalool (17.5%), β-elemene (2.6%) and camphor (1.52%). The results revealed that this plant may belong to the methyl cinnamate and linalool chemotype. A methyl thiazol tetrazolium assay was used for in vitro cytotoxicity screening against the human cervical cancer cell line (HeLa), human laryngeal epithelial carcinoma cell line (HEp-2) and NIH 3T3 mouse embryonic fibroblasts. The IC(50) values obtained were 90.5 and 96.3 µg mL(-1), respectively, and the results revealed that basil oil has potent cytotoxicity.

  2. Proteomic profiling of human embryonic stem cell-derived microvesicles reveals a risk of transfer of proteins of bovine and mouse origin

    Czech Academy of Sciences Publication Activity Database

    Kubíková, I.; Konečná, H.; Šedo, O.; Zdráhal, Z.; Řehulka, Pavel; Hříbková, H.; Řehulková, Helena; Hampl, Aleš; Chmelík, Josef; Dvořák, Petr

    2009-01-01

    Roč. 11, č. 3 (2009), s. 330-340 ISSN 1465-3249 R&D Projects: GA MŠk 1M0538 Institutional research plan: CEZ:AV0Z40310501; CEZ:AV0Z50390512; CEZ:AV0Z50390703 Keywords : human embryonic stem cell * hESC * proteomic profiling Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.204, year: 2009

  3. The rate of X-ray-induced DNA double-strand break repair in the embryonic mouse brain is unaffected by exposure to 50 Hz magnetic fields.

    Science.gov (United States)

    Woodbine, Lisa; Haines, Jackie; Coster, Margaret; Barazzuol, Lara; Ainsbury, Elizabeth; Sienkiewicz, Zenon; Jeggo, Penny

    2015-06-01

    Following in utero exposure to low dose radiation (10-200 mGy), we recently observed a linear induction of DNA double-strand breaks (DSB) and activation of apoptosis in the embryonic neuronal stem/progenitor cell compartment. No significant induction of DSB or apoptosis was observed following exposure to magnetic fields (MF). In the present study, we exploited this in vivo system to examine whether exposure to MF before and after exposure to 100 mGy X-rays impacts upon DSB repair rates. 53BP1 foci were quantified following combined exposure to radiation and MF in the embryonic neuronal stem/progenitor cell compartment. Embryos were exposed in utero to 50 Hz MF at 300 μT for 3 h before and up to 9 h after exposure to 100 mGy X-rays. Controls included embryos exposed to MF or X-rays alone plus sham exposures. Exposure to MF before and after 100 mGy X-rays did not impact upon the rate of DSB repair in the embryonic neuronal stem cell compartment compared to repair rates following radiation exposure alone. We conclude that in this sensitive system MF do not exert any significant level of DNA damage and do not impede the repair of X-ray induced damage.

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

    Science.gov (United States)

    Wei, Qing; Liu, Hongliang; Ai, Zhiying; Wu, Yongyan; Liu, Yingxiang; Shi, Zhaopeng; Ren, Xuexue; Guo, Zekun

    2017-01-01

    Self-renewal is one of the most important features of embryonic stem (ES) cells. SC1 is a small molecule modulator that effectively maintains the self-renewal of mouse ES cells in the absence of leukemia inhibitory factor (LIF), serum and feeder cells. However, the mechanism by which SC1 maintains the undifferentiated state of mouse ES cells remains unclear. In this study, microarray and small RNA deep-sequencing experiments were performed on mouse ES cells treated with or without SC1 to identify the key genes and microRNAs that contributed to self-renewal. SC1 regulates the expressions of pluripotency and differentiation factors, and antagonizes the retinoic acid (RA)-induced differentiation in the presence or absence of LIF. SC1 inhibits the MEK/ERK pathway through Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis and pathway reporting experiments. Small RNA deep-sequencing revealed that SC1 significantly modulates the expression of multiple microRNAs with crucial functions in ES cells. The expression of miR124-3p is upregulated in SC1-treated ES cells, which significantly inhibits the MEK/ERK pathway by targeting Grb2, Sos2 and Egr1. SC1 enhances the self-renewal capacity of mouse ES cells by modulating the expression of key regulatory genes and pluripotency-associated microRNAs. SC1 significantly upregulates miR124-3p expression to further inhibit the MEK/ ERK pathway by targeting Grb2, Sos2 and Egr1. © 2017 The Author(s). Published by S. Karger AG, Basel.

  5. The macro-structural variability of the human neocortex.

    Science.gov (United States)

    Kruggel, Frithjof

    2018-05-15

    The human neocortex shows a considerable individual structural variability. While primary gyri and sulci are found in all normally developed brains and bear clear-cut gross structural descriptions, secondary structures are highly variable and not present in all brains. The blend of common and individual structures poses challenges when comparing structural and functional results from quantitative neuroimaging studies across individuals, and sets limits on the precision of location information much above the spatial resolution of current neuroimaging methods. This work aimed at quantifying structural variability on the neocortex, and at assessing the spatial relationship between regions common to all brains and their individual structural variants. Based on structural MRI data provided as the "900 Subjects Release" of the Human Connectome Project, a data-driven analytic approach was employed here from which the definition of seven cortical "communities" emerged. Apparently, these communities comprise common regions of structural features, while the individual variability is confined within a community. Similarities between the community structure and the state of the brain development at gestation week 32 lead suggest that communities are segregated early. Subdividing the neocortex into communities is suggested as anatomically more meaningful than the traditional lobar structure. Copyright © 2018 Elsevier Inc. All rights reserved.

  6. The emergence of mind and emotion in the evolution of neocortex.

    Science.gov (United States)

    Freeman, Walter J

    2011-01-01

    The most deeply transformative concept for the growth of 21st Century psychiatry is the constellation of the chaotic dynamics of the brain. Brains are no longer seen as rational systems that are plagued with emotional disorders reflecting primitives inherited from our animal ancestors. Brains are dynamical systems that continually create patterns by acting intentionally into the environment and shaping themselves in accord with the sensory consequences of their intended actions. Emotions are now seen not as reversions to animal behaviors but as the sources of force and energy that brains require for the actions they take to understand the world and themselves. Humans are unique in experiencing consciousness of their own actions, which they experience as conscience: guilt, shame, pride and joy. Chaotic brain dynamics strives always for unity and harmony, but as a necessary condition for adaptation to a changing world, it repeatedly lapses into disorder. The successes are seen in the normal unity of consciousness; the failures are seen in the disorders that we rightly label the schizophrenias and the less severe character disorders. The foundation for healthy unity is revealed by studies in the evolution of brains, in particular the way in which neocortex of mammals emerged from the primitive allocortex of reptiles. The amazing facts of brain dynamics are now falling into several places. The power-law connectivity of cortex supports the scale-free dynamics of the global workspace in brains ranging from mouse to whale. That dynamics in humans holds the secrets of speech and symbol utilization. By recursive interactions in vast areas of human neocortex the scale-free connectivity supports our unified consciousness. Here in this dynamics are to be sought the keys to understanding and treating the disorders that uniquely plague the human mind.

  7. Simultaneous suppression of TGF-β and ERK signaling contributes to the highly efficient and reproducible generation of mouse embryonic stem cells from previously considered refractory and non-permissive strains.

    Science.gov (United States)

    Hassani, Seyedeh-Nafiseh; Totonchi, Mehdi; Farrokhi, Ali; Taei, Adeleh; Larijani, Mehran Rezaei; Gourabi, Hamid; Baharvand, Hossein

    2012-06-01

    Mouse embryonic stem cells (ESCs) are pluripotent stem cell lines derived from pre-implantation embryos. The efficiency of mESC generation is affected by genetic variation in mice; that is, some mouse strains are refractory or non-permissive to ESC establishment. Developing an efficient method to derive mESCs from strains of various genetic backgrounds should be valuable for establishment of ESCs in various mammalian species. In the present study, we identified dual inhibition of TGF-β and ERK1/2, by SB431542 and PD0325901, respectively led to the highly efficient and reproducible generation of mESC lines from NMRI, C57BL/6, BALB/c, DBA/2, and FVB/N strains, which previously considered refractory or non-permissive for ESC establishment. These mESCs expressed pluripotency markers and retained the capacity to differentiate into derivatives of all three germ layers. The evaluated lines exhibited high rates of chimerism when reintroduced into blastocysts. To our knowledge, this is the first report of efficient (100%) mESC lines generation from different genetic backgrounds. The application of these two inhibitors will not only solve the problems of mESC derivation but also clarifies new signaling pathways in pluripotent mESCs.

  8. Effect of Vitamin D in HN9.10e Embryonic Hippocampal Cells and in Hippocampus from MPTP-Induced Parkinson’s Disease Mouse Model

    Directory of Open Access Journals (Sweden)

    Samuela Cataldi

    2018-02-01

    Full Text Available It has long been proven that neurogenesis continues in the adult brains of mammals in the dentatus gyrus of the hippocampus due to the presence of neural stem cells. Although a large number of studies have been carried out to highlight the localization of vitamin D receptor in hippocampus, the expression of vitamin D receptor in neurogenic dentatus gyrus of hippocampus in Parkinson’s disease (PD and the molecular mechanisms triggered by vitamin D underlying the production of differentiated neurons from embryonic cells remain unknown. Thus, we performed a preclinical in vivo study by inducing PD in mice with MPTP and showed a reduction of glial fibrillary acidic protein (GFAP and vitamin D receptor in the dentatus gyrus of hippocampus. Then, we performed an in vitro study by inducing embryonic hippocampal cell differentiation with vitamin D. Interestingly, vitamin D stimulates the expression of its receptor. Vitamin D receptor is a transcription factor that probably is responsible for the upregulation of microtubule associated protein 2 and neurofilament heavy polypeptide genes. The latter increases heavy neurofilament protein expression, essential for neurofilament growth. Notably N-cadherin, implicated in activity for dendritic outgrowth, is upregulated by vitamin D.

  9. An ENU-induced point mutation in the mouse Btaf1 gene causes post-gastrulation embryonic lethality and protein instability

    NARCIS (Netherlands)

    Wansleeben, C.; van Gurp, L.; de Graaf, P.; Mousson, F.; Timmers, H.T.; Meijlink, F.

    2011-01-01

    The mouse Btaf1 gene, an ortholog of yeast MOT1, encodes a highly conserved general transcription factor. The function of this SNF2-like ATPase has been studied mainly in yeast and human cells, which has revealed that it binds directly to TBP, forming the B-TFIID complex. This complex binds to core

  10. Hypoxia preferentially destroys GABAergic neurons in developing rat neocortex explants in culture

    NARCIS (Netherlands)

    Romijn, H. J.; Ruijter, J. M.; Wolters, P. S.

    1988-01-01

    The hypothesis that hypoxic ischemia before or during the human birth process preferentially destroys GABAergic nerve cells, particularly in the neocortex, was tested in a tissue culture model system. To that end, rat neocortex explants dissected from 6-day-old rat pups and cultured to a

  11. Subtypes of GABAergic neurons project axons in the neocortex

    Directory of Open Access Journals (Sweden)

    Shigeyoshi Higo

    2009-11-01

    Full Text Available γ-aminobutyric acid (GABAergic neurons in the neocortex have been regarded as interneurons and speculated to modulate the activity of neurons locally. Recently, however, several experiments revealed that neuronal nitric oxide synthase (nNOS-positive GABAergic neurons project cortico-cortically with long axons. In this study, we illustrate Golgi-like images of the nNOS-positive GABAergic neurons using a nicotinamide adenine dinucleotide phosphate diaphorase (NADPH-d reaction and follow the emanating axon branches in cat brain sections. These axon branches projected cortico-cortically with other non-labeled arcuate fibers, contra-laterally via the corpus callosum and anterior commissure. The labeled fibers were not limited to the neocortex but found also in the fimbria of the hippocampus. In order to have additional information on these GABAergic neuron projections, we investigated green fluorescent protein (GFP-labeled GABAergic neurons in GAD67-Cre knock-in / GFP Cre-reporter mice. GFP-labeled axons emanate densely, especially in the fimbria, a small number in the anterior commissure, and very sparsely in the corpus callosum. These two different approaches confirm that not only nNOS-positive GABAergic neurons but also other subtypes of GABAergic neurons project long axons in the cerebral cortex and are in a position to be involved in information processing.

  12. mTOR complex 2 phosphorylates IMP1 cotranslationally to promote IGF2 production and the proliferation of mouse embryonic fibroblasts

    DEFF Research Database (Denmark)

    Dai, Ning; Christiansen, Jan; Nielsen, Finn

    2013-01-01

    uncover a new mechanism by which mTOR regulates organismal growth by promoting IGF2 production in the mouse embryo through mTORC2-catalyzed cotranslational IMP1/IMP3 phosphorylation. Inasmuch as TORC2 is activated by association with ribosomes, the present results indicate that mTORC2-catalyzed...... production, and diminished proliferation. The proliferation of the IMP1-null fibroblasts can be restored to wild-type levels by IGF2 in vitro or by re-expression of IMP1, which corrects the defects in IGF2 RNA splicing and translation. The ability of IMP1 to correct these defects is dependent on IMP1...

  13. Absence of collagen IX accelerates hypertrophic differentiation in the embryonic mouse spine through a disturbance of the Ihh-PTHrP feedback loop.

    Science.gov (United States)

    Kamper, Matthias; Paulsson, Mats; Zaucke, Frank

    2017-02-01

    Collagen IX (Col IX) is a component of the cartilage extracellular matrix and contributes to its structural integrity. Polymorphisms in the genes encoding the Col IX ɑ2- and ɑ3-chains are associated with early onset of disc degeneration. Col IX-deficient mice already display changes in the spine at the newborn stage and premature disc degeneration starting at 6 months of age. To determine the role of Col IX in early spine development and to identify molecular mechanisms underlying disc degeneration, the embryonic development of the spine was analyzed in Col IX -/- mice. Histological staining was used to show tissue morphology at different time points. Localization of extracellular matrix proteins as well as components of signaling pathways were analyzed by immunohistochemistry. Developing vertebral bodies of Col IX -/- mice were smaller and already appeared more compact at E12.5. At E15.5, vertebral bodies of Col IX -/- mice revealed an increased number of hypertrophic chondrocytes as well as enhanced staining for the terminal differentiation markers alkaline phosphatase and collagen X. This correlates with an imbalance in the Ihh-PTHrP signaling pathway at this time point, reflected by an increase of Ihh and a concomitant decrease of PTHrP expression. An accelerated hypertrophic differentiation caused by a disturbed Ihh-PTHrP signaling pathway may lead to a higher bone mineral density in the vertebral bodies of newborn Col IX -/- mice and, as a result, to the early onset of disc degeneration.

  14. The PR/SET Domain Zinc Finger Protein Prdm4 Regulates Gene Expression in Embryonic Stem Cells but Plays a Nonessential Role in the Developing Mouse Embryo

    Science.gov (United States)

    Bogani, Debora; Morgan, Marc A. J.; Nelson, Andrew C.; Costello, Ita; McGouran, Joanna F.; Kessler, Benedikt M.

    2013-01-01

    Prdm4 is a highly conserved member of the Prdm family of PR/SET domain zinc finger proteins. Many well-studied Prdm family members play critical roles in development and display striking loss-of-function phenotypes. Prdm4 functional contributions have yet to be characterized. Here, we describe its widespread expression in the early embryo and adult tissues. We demonstrate that DNA binding is exclusively mediated by the Prdm4 zinc finger domain, and we characterize its tripartite consensus sequence via SELEX (systematic evolution of ligands by exponential enrichment) and ChIP-seq (chromatin immunoprecipitation-sequencing) experiments. In embryonic stem cells (ESCs), Prdm4 regulates key pluripotency and differentiation pathways. Two independent strategies, namely, targeted deletion of the zinc finger domain and generation of a EUCOMM LacZ reporter allele, resulted in functional null alleles. However, homozygous mutant embryos develop normally and adults are healthy and fertile. Collectively, these results strongly suggest that Prdm4 functions redundantly with other transcriptional partners to cooperatively regulate gene expression in the embryo and adult animal. PMID:23918801

  15. Sevoflurane represses the self-renewal ability by regulating miR-7a,7b/Klf4 signalling pathway in mouse embryonic stem cells.

    Science.gov (United States)

    Wang, Qimin; Li, Guifeng; Li, Baolin; Chen, Qiu; Lv, Dongdong; Liu, Jiaying; Ma, Jieyu; Sun, Nai; Yang, Longqiu; Fei, Xuejie; Song, Qiong

    2016-10-01

    Sevoflurane is a frequently-used clinical inhalational anaesthetic and can cause toxicity to embryos during foetal development. Embryonic stem cells (ESCs) are derived from the inner cell mass of blastospheres and can be used as a useful model of early development. Here, we found that sevoflurane significantly influenced self-renewal ability of mESCs on stemness maintenance and cell proliferation. The cell cycle was arrested via G1 phase delay. We further found that sevoflurane upregulated expression of miR-7a,7b to repress self-renewal. Next we performed rescue experiments and found that after adding miR-7a,7b inhibitor into mESCs treated with sevoflurane, its influence on self-renewal could be blocked. Further we identified stemness factor Klf4 as the direct target of miR-7a,7b. Overexpression of Klf4 restored self-renewal ability repressed by miR-7a,7b or sevoflurane. In this work, we determined that sevoflurane repressed self-renewal ability by regulating the miR-7a,7b/Klf4 signalling pathway in mESCs. Our study demonstrated molecular mechanism underlying the side effects of sevoflurane during early development, laying the foundation for studies on safe usage of inhalational anaesthetic during non-obstetric surgery. © 2016 John Wiley & Sons Ltd.

  16. AMP-activated protein kinase α2 and E2F1 transcription factor mediate doxorubicin-induced cytotoxicity by forming a positive signal loop in mouse embryonic fibroblasts and non-carcinoma cells.

    Science.gov (United States)

    Yang, Wookyeom; Park, In-Ja; Yun, Hee; Im, Dong-Uk; Ock, Sangmi; Kim, Jaetaek; Seo, Seon-Mi; Shin, Ha-Yeon; Viollet, Benoit; Kang, Insug; Choe, Wonchae; Kim, Sung-Soo; Ha, Joohun

    2014-02-21

    Doxorubicin is one of the most widely used anti-cancer drugs, but its clinical application is compromised by severe adverse effects in different organs including cardiotoxicity. In the present study we explored mechanisms of doxorubicin-induced cytotoxicity by revealing a novel role for the AMP-activated protein kinase α2 (AMPKα2) in mouse embryonic fibroblasts (MEFs). Doxorubicin robustly induced the expression of AMPKα2 in MEFs but slightly reduced AMPKα1 expression. Our data support the previous notion that AMPKα1 harbors survival properties under doxorubicin treatment. In contrast, analyses of Ampkα2(-/-) MEFs, gene knockdown of AMPKα2 by shRNA, and inhibition of AMPKα2 activity with an AMPK inhibitor indicated that AMPKα2 functions as a pro-apoptotic molecule under doxorubicin treatment. Doxorubicin induced AMPKα2 at the transcription level via E2F1, a transcription factor that regulates apoptosis in response to DNA damage. E2F1 directly transactivated the Ampkα2 gene promoter. In turn, AMPKα2 significantly contributed to stabilization and activation of E2F1 by doxorubicin, forming a positive signal amplification loop. AMPKα2 directly interacted with and phosphorylated E2F1. This signal loop was also detected in H9c2, C2C12, and ECV (human epithelial cells) cells as well as mouse liver under doxorubicin treatment. Resveratrol, which has been suggested to attenuate doxorubicin-induced cytotoxicity, significantly blocked induction of AMPKα2 and E2F1 by doxorubicin, leading to protection of these cells. This signal loop appears to be non-carcinoma-specific because AMPKα2 was not induced by doxorubicin in five different tested cancer cell lines. These results suggest that AMPKα2 may serve as a novel target for alleviating the cytotoxicity of doxorubicin.

  17. Quantitative LC-MS Provides No Evidence for m6 dA or m4 dC in the Genome of Mouse Embryonic Stem Cells and Tissues.

    Science.gov (United States)

    Schiffers, Sarah; Ebert, Charlotte; Rahimoff, René; Kosmatchev, Olesea; Steinbacher, Jessica; Bohne, Alexandra-Viola; Spada, Fabio; Michalakis, Stylianos; Nickelsen, Jörg; Müller, Markus; Carell, Thomas

    2017-09-04

    Until recently, it was believed that the genomes of higher organisms contain, in addition to the four canonical DNA bases, only 5-methyl-dC (m 5 dC) as a modified base to control epigenetic processes. In recent years, this view has changed dramatically with the discovery of 5-hydroxymethyl-dC (hmdC), 5-formyl-dC (fdC), and 5-carboxy-dC (cadC) in DNA from stem cells and brain tissue. N 6 -methyldeoxyadenosine (m 6 dA) is the most recent base reported to be present in the genome of various eukaryotic organisms. This base, together with N 4 -methyldeoxycytidine (m 4 dC), was first reported to be a component of bacterial genomes. In this work, we investigated the levels and distribution of these potentially epigenetically relevant DNA bases by using a novel ultrasensitive UHPLC-MS method. We further report quantitative data for m 5 dC, hmdC, fdC, and cadC, but we were unable to detect either m 4 dC or m 6 dA in DNA isolated from mouse embryonic stem cells or brain and liver tissue, which calls into question their epigenetic relevance. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Comparison of the mouse Embryonic Stem cell Test, the rat Whole Embryo Culture and the Zebrafish Embryotoxicity Test as alternative methods for developmental toxicity testing of six 1,2,4-triazoles

    International Nuclear Information System (INIS)

    Jong, Esther de; Barenys, Marta; Hermsen, Sanne A.B.; Verhoef, Aart; Ossendorp, Bernadette C.; Bessems, Jos G.M.; Piersma, Aldert H.

    2011-01-01

    The relatively high experimental animal use in developmental toxicity testing has stimulated the search for alternatives that are less animal intensive. Three widely studied alternative assays are the mouse Embryonic Stem cell Test (EST), the Zebrafish Embryotoxicity Test (ZET) and the rat postimplantation Whole Embryo Culture (WEC). The goal of this study was to determine their efficacy in assessing the relative developmental toxicity of six 1,2,4-triazole compounds, flusilazole, hexaconazole, cyproconazole, triadimefon, myclobutanil and triticonazole. For this purpose, we analyzed effects and relative potencies of the compounds in and among the alternative assays and compared the findings to their known in vivo developmental toxicity. Triazoles are antifungal agents used in agriculture and medicine, some of which are known to induce craniofacial and limb abnormalities in rodents. The WEC showed a general pattern of teratogenic effects, typical of exposure to triazoles, mainly consisting of reduction and fusion of the first and second branchial arches, which are in accordance with the craniofacial malformations reported after in vivo exposure. In the EST all triazole compounds inhibited cardiomyocyte differentiation concentration-dependently. Overall, the ZET gave the best correlation with the relative in vivo developmental toxicities of the tested compounds, closely followed by the EST. The relative potencies observed in the WEC showed the lowest correlation with the in vivo developmental toxicity data. These differences in the efficacy between the test systems might be due to differences in compound kinetics, in developmental stages represented and in the relative complexity of the alternative assays.

  19. Vitamin C induces specific demethylation of H3K9me2 in mouse embryonic stem cells via Kdm3a/b.

    Science.gov (United States)

    Ebata, Kevin T; Mesh, Kathryn; Liu, Shichong; Bilenky, Misha; Fekete, Alexander; Acker, Michael G; Hirst, Martin; Garcia, Benjamin A; Ramalho-Santos, Miguel

    2017-01-01

    Histone methylation patterns regulate gene expression and are highly dynamic during development. The erasure of histone methylation is carried out by histone demethylase enzymes. We had previously shown that vitamin C enhances the activity of Tet enzymes in embryonic stem (ES) cells, leading to DNA demethylation and activation of germline genes. We report here that vitamin C induces a remarkably specific demethylation of histone H3 lysine 9 dimethylation (H3K9me2) in naïve ES cells. Vitamin C treatment reduces global levels of H3K9me2, but not other histone methylation marks analyzed, as measured by western blot, immunofluorescence and mass spectrometry. Vitamin C leads to widespread loss of H3K9me2 at large chromosomal domains as well as gene promoters and repeat elements. Vitamin C-induced loss of H3K9me2 occurs rapidly within 24 h and is reversible. Importantly, we found that the histone demethylases Kdm3a and Kdm3b are required for vitamin C-induced demethylation of H3K9me2. Moreover, we show that vitamin C-induced Kdm3a/b-mediated H3K9me2 demethylation and Tet-mediated DNA demethylation are independent processes at specific loci. Lastly, we document Kdm3a/b are partially required for the upregulation of germline genes by vitamin C. These results reveal a specific role for vitamin C in histone demethylation in ES cells and document that DNA methylation and H3K9me2 cooperate to silence germline genes in pluripotent cells.

  20. Characterisation of Signalling by the Endogenous GPER1 (GPR30 Receptor in an Embryonic Mouse Hippocampal Cell Line (mHippoE-18.

    Directory of Open Access Journals (Sweden)

    Nicholas J Evans

    Full Text Available Estrogen can modulate neuronal development and signalling by both genomic and non-genomic pathways. Many of its rapid, non-genomic effects on nervous tissue have been suggested to be mediated via the activation of the estrogen sensitive G-protein coupled receptor (GPER1 or GPR30. There has been much controversy over the cellular location, signalling properties and endogenous activators of GPER1. Here we describe the pharmacology and signalling properties of GPER1 in an immortalized embryonic hippocampal cell line, mHippoE-18. This cell line does not suffer from the inherent problems associated with the study of this receptor in native tissue or the problems associated with heterologously expression in clonal cell lines. In mHippoE-18 cells, 17β-Estradiol can mediate a dose-dependent rapid potentiation of forskolin-stimulated cyclic AMP levels but does not appear to activate the ERK1/2 pathway. The effect of 17β-Estradiol can be mimicked by the GPER1 agonist, G1, and also by tamoxifen and ICI 182,780 which activate GPER1 in a variety of other preparations. The response is not mimicked by the application of the classical estrogen receptor agonists, PPT, (an ERα agonist or DPN, (an ERβ agonist, further suggesting that this effect of 17β-Estradiol is mediated through the activation of GPER1. However, after exposure of the cells to the GPER1 specific antagonists, G15 and G36, the stimulatory effects of the above agonists are replaced by dose-dependent inhibitions of forskolin-stimulated cyclic AMP levels. This inhibitory effect is mimicked by aldosterone in a dose-dependent way even in the absence of the GPER1 antagonists. The results are discussed in terms of possible "Biased Antagonism" whereby the antagonists change the conformation of the receptor resulting in changes in the agonist induced coupling of the receptor to different second messenger pathways.

  1. A late requirement for Wnt and FGF signalling during activin-induced formation of foregut endoderm from mouse embryonic stem cells

    DEFF Research Database (Denmark)

    Hansson, Mattias; Petersen, Dorthe Rønn; Peterslund, Janny M.L.

    2009-01-01

    Here we examine how BMP, Wnt, and FGF signaling modulate activin-induced mesendodermal differentiation of mouse ES cells grown under defined conditions in adherent monoculture. We monitor ES cells containing reporter genes for markers of primitive streak (PS) and its progeny and extend previous...... is found at the lowest activin concentration. The expression of Gsc and other anterior markers induced by activin is prevented by treatment with BMP4, which induces T expression and subsequent mesodermal development. We show that canonical Wnt signaling is required only during late stages of activin....... Notably, activin induction of Gsc-GFP(+) cells appears refractory to inhibition of canonical Wnt signaling but shows a dependence on early as well as late FGF signaling. Additionally, we find a late dependence on FGF signaling during induction of Sox17(+) cells by activin while BMP4-induced T expression...

  2. Neutral Sphingomyelinase Behaviour in Hippocampus Neuroinflammation of MPTP-Induced Mouse Model of Parkinson’s Disease and in Embryonic Hippocampal Cells

    Directory of Open Access Journals (Sweden)

    Samuela Cataldi

    2017-01-01

    Full Text Available Neutral sphingomyelinase is known to be implicated in growth arrest, differentiation, proliferation, and apoptosis. Although previous studies have reported the involvement of neutral sphingomyelinase in hippocampus physiopathology, its behavior in the hippocampus during Parkinson’s disease remains undetected. In this study, we show an upregulation of inducible nitric oxide synthase and a downregulation of neutral sphingomyelinase in the hippocampus of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine- (MPTP- induced mouse model of Parkinson’s disease. Moreover, the stimulation of neutral sphingomyelinase activity with vitamin 1,25-dihydroxyvitamin D3 reduces specifically saturated fatty acid sphingomyelin by making sphingomyelin a less rigid molecule that might influence neurite plasticity. The possible biological relevance of the increase of neutral sphingomyelinase in Parkinson’s disease is discussed.

  3. Taurine activates GABAergic networks in the neocortex of immature mice

    Directory of Open Access Journals (Sweden)

    Bogdan Aurel Sava

    2014-02-01

    Full Text Available Although it has been suggested that taurine is the main endogenous neurotransmitter acting on glycine receptors, the implications of glycine receptor-mediated taurine actions on immature neocortical networks have not been addressed yet. To investigate the influence of taurine on the excitability of neuronal networks in the immature neocortex, we performed whole-cell patch-clamp recordings from visually identified pyramidal neurons and interneurons in coronal slices from C57Bl/6 and GAD67-GFP transgenic mice (postnatal days 2-4. In 46 % of the pyramidal neurons bath-application of taurine at concentrations ≥ 300 mM significantly enhanced the frequency of postsynaptic currents (PSCs by 744.3 ± 93.8 % (n = 120 cells. This taurine-induced increase of PSC frequency was abolished by 0.2 mM tetrodotoxine, 1 mM strychnine or 3 mM gabazine, but was unaffected by the glutamatergic antagonists 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX and (± R(--3-(2-carboxypiperazine-4-yl-propyl-1-phosphonic acid (CPP, suggesting that taurine specifically activates GABAergic network activity projecting to pyramidal neurons. Cell-attached recordings revealed that taurine enhanced the frequency of action potentials in pyramidal neurons, indicating an excitatory action of the GABAergic PSCs. In order to identify the presynaptic targets of taurine we demonstrate that bath application of taurine induced in GAD67-GFP labeled interneurons an inward current that is mainly mediated by glycine receptors and can generate action potentials in these cells. We conclude from these results that taurine can enhance network excitability in the immature neocortex by selectively activating GABAergic interneurons via interactions with glycine receptors.

  4. The use of the mouse chimera assay to detect early embryonic damage from male mice exposed to low-dose radiation

    International Nuclear Information System (INIS)

    Oudiz, D.; Warner, P.; Walsh, K.J.; Wiley, L.

    1990-01-01

    Mouse chimeras are in vitro aggregations of two 4-cell embryos and are used to detect subtle, nonlethal changes, which are expressed as a proliferative disadvantage in exposed embryos. One of the embryos is labeled with a viable dye (FITC) in order to determine the relative cellular contribution of each embryo when the chimera is dissociated 40 hours later. This proliferative disadvantage has been seen at doses which do not produce an effect on cell number when the embryos are cultured singly. Previously, the assay has detected a decrease in cellular proliferation in embryos from male mice exposed to a single dose of x-radiation as low as 0.05 Gy. In the current study, male mice were irradiated with a single dose of 0, 0.001, 0.01, or 0.05 Gy, and then serially mated for the next 8 weeks to unexposed females. Chimeras were constructed from control and treated embryos. Embryos from males treated with 0.05 Gy exhibited a significant decrease in cellular proliferation during weeks 6 and 7 post-irradiation. A similar decrease was seen in the males treated with 0.01 Gy. No reductions were observed from embryos cultured singly in any of the treatment groups

  5. Cell surface response of chemically transformed, malignant mouse embryonal fibroblasts and human colon cancer cells to the maturation-promoting agent, N,N-dimethylformamide

    International Nuclear Information System (INIS)

    Marks, M.E.

    1985-01-01

    The lactoperoxidase/ 125 I radioiodination procedure was used to probe the cell surface of normal, nontransformed AKR-2B mouse embryo fibroblasts and malignant, permanently methylcholanthrene-transformed AKR-2B (AKR-MCA) cells to establish the relationship between cell surface changes and transformation/differentiation in this call system. AKR-MCA cells displayed surface alterations secondary to N,N-dimethylformamide (DFM)-promoted differentiation. Growth of AKR-MCA cells in DMF virtually eliminated the 85,000 and 63,000 molecular weight surface proteins susceptible to radioiodination and increased surface material of ∼200,000 molecular weight. Thus, surface profiles of DFM-treated AKR-MCA cells were essentially identical to those of nontransformed AKR-2B cells. Experimentation was extended to a cultured human colon cancer cell line (HCT MOSER). HCT MOSER cells exposed to DMF manifested marked, reversible morphological and surface changes which occurred as a function of time of growth in DMF and DMF concentration. Interestingly, material reactive with anti-fibronectin was found on the surfaces and in the culture medium of DFM-treated HCT MOSER cells

  6. Effect of long-term culture of mouse embryonic stem cells under low oxygen concentration as well as on glycosaminoglycan hyaluronan on cell proliferation and differentiation.

    Science.gov (United States)

    Ramírez, M Á; Pericuesta, E; Yáñez-Mó, M; Palasz, A; Gutiérrez-Adán, A

    2011-02-01

    Maintaining undifferentiated stem cells in defined conditions is of critical importance to improve their in vitro culture. We have evaluated the effects of culturing mouse stem (mES) cells under physiological oxygen concentration as well as by replacing fibroblast feeder layer (mEF) with gelatin or glycosaminoglycan hyaluronan (HA), on cell proliferation and differentiation. After 3 days culture or after long-term cell culture under different conditions, levels of apoptotic cell death were determined by cell cycle and TUNEL (TdT-mediated dUTP nick end labelling) assays and levels of cell proliferation by CFSE (5-(and-6)-carboxyfluorescein diacetate succinimidyl ester) labelling. We assessed spontaneous differentiation into cardiomyocytes and mRNA expression of pluripotency and differentiation biomarkers. After 3 days culture under hypoxic conditions, levels of proliferation and apoptosis of mES cells were higher, in correlation with increase in intracellular reactive oxygen species. However, when cells were continuously grown for 1 month under those conditions, the level of apoptosis was, in all cases, under 4%. Hypoxia reduced spontaneous differentiation of mES into cardiomyocytes. Long-term culture on HA was more effective in maintaining the pluripotent state of the mES cells when compared to that on gelatin. Level of terminal differentiation was highest on mEF, intermediate on HA and lowest on gelatin. Our data suggest that hypoxia is not necessary for maintaining pluripotency of mES cells and appeared to be detrimental during ES differentiation. Moreover, HA may offer a valuable alternative for long-term culture of mES cells in vitro. © 2010 Blackwell Publishing Ltd.

  7. Effects of different feeder layers on culture of bovine embryonic stem cell-like cells in vitro.

    Science.gov (United States)

    Cong, Shan; Cao, Guifang; Liu, Dongjun

    2014-12-01

    To find a suitable feeder layer is important for successful culture conditions of bovine embryonic stem cell-like cells. In this study, expression of pluripotency-related genes OCT4, SOX2 and NANOG in bovine embryonic stem cell-like cells on mouse embryonic fibroblast feeder layers at 1-5 passages were monitored in order to identify the possible reason that bovine embryonic stem cell-like cells could not continue growth and passage. Here, we developed two novel feeder layers, mixed embryonic fibroblast feeder layers of mouse and bovine embryonic fibroblast at different ratios and sources including mouse fibroblast cell lines. The bovine embryonic stem cell-like cells generated in our study displayed typical stem cell morphology and expressed specific markers such as OCT4, stage-specific embryonic antigen 1 and 4, alkaline phosphatase, SOX2, and NANOG mRNA levels. When feeder layers and cell growth factors were removed, the bovine embryonic stem cell-like cells formed embryoid bodies in a suspension culture. Furthermore, we compared the expression of the pluripotent markers during bovine embryonic stem cell-like cell in culture on mixed embryonic fibroblast feeder layers, including mouse fibroblast cell lines feeder layers and mouse embryonic fibroblast feeder layers by real-time quantitative polymerase chain reaction. Results suggested that mixed embryonic fibroblast and sources including mouse fibroblast cell lines feeder layers were more suitable for long-term culture and growth of bovine embryonic stem cell-like cells than mouse embryonic fibroblast feeder layers. The findings may provide useful experimental data for the establishment of an appropriate culture system for bovine embryonic stem cell lines.

  8. Visualization of cholinoceptive neurons in the rat neocortex : colocalization of muscarinic and nicotinic acetylcholine receptors

    NARCIS (Netherlands)

    Zee, E.A. van der; Streefland, C.; Strosberg, A.D.; Schröder, H.; Luiten, P.G.M.

    The present investigation analyzes the cellular distribution of muscarinic and nicotinic acetylcholine receptors in rat neocortex, by use of monoclonal antibodies raised against purified receptor proteins. The degree of colocalization of both types of receptors was determined by way of

  9. Neurons in the white matter of the adult human neocortex

    Directory of Open Access Journals (Sweden)

    M Luisa Suarez-Sola

    2009-06-01

    Full Text Available The white matter (WM of the adult human neocortex contains the so-called “interstitial neurons”. They are most numerous in the superficial WM underlying the cortical gyri, and decrease in density toward the deep WM. They are morphologically heterogeneous. A subgroup of interstitial neurons display pyramidal-cell like morphologies, characterized by a polarized dendritic tree with a dominant apical dendrite, and covered with a variable number of dendritic spines. In addition, a large contingent of interstitial neurons can be classified as interneurons based on their neurochemical profile as well as on morphological criteria. WM- interneurons have multipolar or bipolar shapes and express GABA and a variety of other neuronal markers, such as calbindin and calretinin, the extracellular matrix protein reelin, or neuropeptide Y, somatostatin, and nitric oxide synthase. The heterogeneity of interstitial neurons may be relevant for the pathogenesis of Alzheimer disease and schizophrenia. Interstitial neurons are most prominent in human brain, and only rudimentary in the brain of non-primate mammals. These evolutionary differences have precluded adequate experimental work on this cell population, which is usually considered as a relict of the subplate, a transient compartment proper of development and without a known function in the adult brain. The primate-specific prominence of the subplate in late fetal stages points to an important role in the establishment of interstitial neurons. Neurons in the adult WM may be actively involved in coordinating inter-areal connectivity and regulation of blood flow. Further studies in primates will be needed to elucidate the developmental history, adult components and activities of this large neuronal system.

  10. Neocortex and allocortex respond differentially to cellular stress in vitro and aging in vivo.

    Directory of Open Access Journals (Sweden)

    Jessica M Posimo

    Full Text Available In Parkinson's and Alzheimer's diseases, the allocortex accumulates aggregated proteins such as synuclein and tau well before neocortex. We present a new high-throughput model of this topographic difference by microdissecting neocortex and allocortex from the postnatal rat and treating them in parallel fashion with toxins. Allocortical cultures were more vulnerable to low concentrations of the proteasome inhibitors MG132 and PSI but not the oxidative poison H2O2. The proteasome appeared to be more impaired in allocortex because MG132 raised ubiquitin-conjugated proteins and lowered proteasome activity in allocortex more than neocortex. Allocortex cultures were more vulnerable to MG132 despite greater MG132-induced rises in heat shock protein 70, heme oxygenase 1, and catalase. Proteasome subunits PA700 and PA28 were also higher in allocortex cultures, suggesting compensatory adaptations to greater proteasome impairment. Glutathione and ceruloplasmin were not robustly MG132-responsive and were basally higher in neocortical cultures. Notably, neocortex cultures became as vulnerable to MG132 as allocortex when glutathione synthesis or autophagic defenses were inhibited. Conversely, the glutathione precursor N-acetyl cysteine rendered allocortex resilient to MG132. Glutathione and ceruloplasmin levels were then examined in vivo as a function of age because aging is a natural model of proteasome inhibition and oxidative stress. Allocortical glutathione levels rose linearly with age but were similar to neocortex in whole tissue lysates. In contrast, ceruloplasmin levels were strikingly higher in neocortex at all ages and rose linearly until middle age. PA28 levels rose with age and were higher in allocortex in vivo, also paralleling in vitro data. These neo- and allocortical differences have implications for the many studies that treat the telencephalic mantle as a single unit. Our observations suggest that the topographic progression of protein

  11. Versatile and simple approach to determine astrocyte territories in mouse neocortex and hippocampus.

    Directory of Open Access Journals (Sweden)

    Antje Grosche

    Full Text Available BACKGROUND: Besides their neuronal support functions, astrocytes are active partners in neuronal information processing. The typical territorial structure of astrocytes (the volume of neuropil occupied by a single astrocyte is pivotal for many aspects of glia-neuron interactions. METHODS: Individual astrocyte territorial volumes are measured by Golgi impregnation, and astrocyte densities are determined by S100β immunolabeling. These data are compared with results from conventionally applied methods such as dye filling and determination of the density of astrocyte networks by biocytin loading. Finally, we implemented our new approach to investigate age-related changes in astrocyte territories in the cortex and hippocampus of 5- and 21-month-old mice. RESULTS: The data obtained by our simplified approach based on Golgi impregnation were compared to previously published dye filling experiments, and yielded remarkably comparable results regarding astrocyte territorial volumes. Moreover, we found that almost all coupled astrocytes (as indicated by biocytin loading were immunopositive for S100β. A first application of this new experimental approach gives insight in age-dependent changes in astrocyte territorial volumes. They increased with age, while cell densities remained stable. In 5-month-old mice, the overlap factor was close to 1, revealing little or no interdigitation of astrocyte territories. However, in 21-month-old mice, the overlap factor was more than 2, suggesting that processes of adjacent astrocytes interdigitate. CONCLUSION: Here we verified the usability of a simple, versatile method for assessing astrocyte territories and the overlap factor between adjacent territories. Second, we found that there is an age-related increase in territorial volumes of astrocytes that leads to loss of the strict organization in non-overlapping territories. Future studies should elucidate the physiological relevance of this adaptive reaction of astrocytes in the aging brain and the methods presented in this study might be a powerful tool to do so.

  12. Repair of Neocortex in a Model of Cortical Dysplasia

    Science.gov (United States)

    2007-03-27

    as dyslexia, intractable epilepsy, and schizophrenia which has been linked to abnormal reelin expression (Grayson et al., 2005; Brigman et al., 2006...exposure to ethanol on glutamate and GABA immunoreactivity in macaque somatosensory and motor cortices: critical timing of exposure. Neuroscience...Rothblat LA (2006) Executive functions in the heterozygous reeler mouse model of schizophrenia . Behav Neurosci 120:984-988. Caldwell MA, He X

  13. Genetic enrichment of cardiomyocytes derived from mouse ...

    African Journals Online (AJOL)

    Jane

    2011-06-22

    Jun 22, 2011 ... Pluripotent embryonic stem cells (ESC) have the ability to differentiate into a ... We describe a simple method to generate relatively pure cardiomyocytes from mouse ... In this study, we described the generation of transgenic.

  14. Genetic enrichment of cardiomyocytes derived from mouse ...

    African Journals Online (AJOL)

    Genetic enrichment of cardiomyocytes derived from mouse embryonic stem cells. WJ He, SC Li, LL Ye, H Liu, QW Wang, WD Han, XB Fu, ZL Chen. Abstract. Pluripotent embryonic stem cells (ESC) have the ability to differentiate into a variety of cell lineages in vitro, including cardiomyocytes. Successful applications of ...

  15. A procedure for culturing rat neocortex explants in a serum-free nutrient medium

    NARCIS (Netherlands)

    Romijn, H. J.; de Jong, B. M.; Ruijter, J. M.

    1988-01-01

    A procedure is described for long-term culturing of rat neocortex explants in a serum-free growth medium. Slices spanning the entire cortical depth from pial to ventricular side are prepared from 6-day-old rat pups. After preincubation in Hanks' balanced salt solution with extra glucose, the

  16. Total regional and global number of synapses in the human brain neocortex

    NARCIS (Netherlands)

    Tang, Y.; Nyengaard, J.R.; Groot, D.M.G. de; Jorgen, H.; Gundersen, G.

    2001-01-01

    An estimator of the total number of synapses in neocortex of human autopsy brains based on unbiased stereological principles is described. Each randomly chosen cerebral hemisphere was stratified into the four major neocortical regions. Uniform sampling with a varying sampling fraction in each region

  17. Comparing Epileptiform Behavior of Mesoscale Detailed Models and Population Models of Neocortex

    NARCIS (Netherlands)

    Visser, S.; Meijer, Hil Gaétan Ellart; Lee, Hyong C.; van Drongelen, Wim; van Putten, Michel Johannes Antonius Maria; van Gils, Stephanus A.

    2010-01-01

    Two models of the neocortex are developed to study normal and pathologic neuronal activity. One model contains a detailed description of a neocortical microcolumn represented by 656 neurons, including superficial and deep pyramidal cells, four types of inhibitory neurons, and realistic synaptic

  18. Modulatory Effects of Dopamine D2 Receptors on Spreading Depression in Rat Somatosensory Neocortex

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    Anna Maria Haarmann

    2014-11-01

    Full Text Available Introduction: Spreading depression (SD is a propagating wave of depolarization followed by depression of the neuroglial activities and can modulate extracellular dopamine concentrations in the neocortex. It has been shown that the dopaminergic system plays a role in migraine. SD has been suggested as a critical phenomenon in the pathophysiology of migraine. The aim of this study was to investigate the effect of dopamine D2 receptors on the characteristic features of SD in rat neocortical tissues. Methods: The effect of dopamine D2 receptor agonist quinpirole and D2 receptor antagonist sulpiride was tested on different characteristic features (amplitude, duration and velocity of KCl-induced SD in somatosensory neocortical slices of adult rats. The effect of above-mentioned substances on production of long-term potentiation (LTP in the neocortex was also evaluated. Results: The present data revealed a dose-dependent suppression of the amplitude and duration of SD in the presence of the dopamine D2 receptor antagonist sulpiride in the neocortex. D2 dopamine receptor agonist quinpirole dose-dependently enhanced the amplitude and duration of the neocortical SD. Furthermore, application of D2 receptor antagonist significantly suppressed induction of LTP. Discussion: These results indicate that D2 receptors modulate the initiation of SD in the neocortex. This finding refers to the potential role of D2 receptor antagonist in treatment of migraine pain.

  19. Immunocytochemical indications for neuronal co-localization of GABA and aspartate in cultured neocortex explants

    NARCIS (Netherlands)

    de Jong, B. M.; Ruijter, J. M.; Buijs, R. M.

    1989-01-01

    The application of postembedding immunocytochemistry on serial semithin plastic sections, revealed the presence of gamma-aminobutyric acid (GABA)-positive and aspartate-positive neurons in cultured neocortex explants. GABA-positive neurons were found in all layers of the cultured cortex, whereas

  20. DIFFERENTIATION OF EMBRYONIC STEM CELLS: LESSONS FROM EMBRYONIC DEVELOPMENT

    Directory of Open Access Journals (Sweden)

    EMOKE PALL

    2008-05-01

    Full Text Available Embryonic stem (ES cells, the undifferentiated cells of early embryos are established as permanent lines and are characterised by their self-renewal capacity and the ability to retain their developmental capacity in vivo and in vitro. The pluripotent properties of ES cells are the basis of gene targeting technologies used to create mutant mouse strains with inactivated genes by homologous recombination. There are several methods to induce the formation of EBs. One of them the formation by aggregating ES cells in hanging drops, using gravity as an aggregation force. This method presents the advantage of obtaining well-calibrated EBs almost identical in size. We used at our experiment the mouse ES cell line KA1/11/C3/C8 with a normal karyotype, at 14th passages. Immunohistochemical examination was aimed to identify tissue-restricted proteins for the two differentiated lineages: titin as a cell-specific antigen for cardiac and skeletal muscle, betaIII-tubulin for the neuronal differentiation, cytokeratin Endo-A (TROMA for the presence of mesenchymal progenitor cells, Oct-4 for the presence of the undifferentiated ES cells. The beating cardiac muscle clumps showed more synchronous rhythm than those seen in EBs obtained from suspension culture method, where the beating cardiac muscle clumps appeared later, had a lower frequency and were uneven. The synaptic networks of neuronal cells were best developed in EBs from suspension, compared to those observed in EBs from hanging-drop method.

  1. Targeted Ablation and Reorganization of the Principal Preplate Neurons and Their Neuroblasts Identified by Golli Promoter Transgene Expression in the Neocortex of Mice

    Directory of Open Access Journals (Sweden)

    Yuan-Yun Xie

    2009-10-01

    Full Text Available The present study delineates the cellular responses of dorsal pallium to targeted genetic ablation of the principal preplate neurons of the neocortex. Ganciclovir treatment during prenatal development (E11-E13; where E is embryonic day of mice selectively killed cells with shared S-phase vulnerability and targeted expression of a GPT [golli promoter transgene, linked to HSV-TK (herpes simplex virus-thymidine kinase, τ-eGFP (τ-enhanced green fluorescent protein and lacZ (lacZ galactosidase reporters] localized in preplate neurons. Morphogenetic fates of attacked neurons and neuroblasts, and their successors, were assessed by multiple labelling in time-series comparisons between ablated (HSV-TK+/0 and control (HSV-TK0/0 littermates. During ablation generation, neocortical growth was suppressed, and compensatory reorganization of non-GPT ventricular zone progenitors of dorsal pallium produced replacements for killed GPT neuroblasts. Replacement and surviving GPT neuroblasts then produced replacements for killed GPT neurons. Near-normal restoration of their complement delayed the settlement of GPT neurons into the reconstituted preplate, which curtailed the outgrowth of pioneer corticofugal axons. Based on this evidence, we conclude that specific cell killing in ablated mice can eliminate a major fraction of GPT neurons, with insignificant bystander killing. Also, replacement GPT neurons in ablated mice originate exclusively by proliferation from intermediate progenitor GPT neuroblasts, whose complement is maintained by non-GPT progenitors for inductive regulation of the total complement of GPT neurons. Finally, GPT neurons in both normal and ablated mice meet all morphogenetic criteria, including the ‘outside-in’ vertical gradient of settlement, presently used to identify principal preplate neurons. In ablated mice, delayed organization of these neurons desynchronizes and isolates developing neocortex from the rest of the brain, and

  2. Dibucaine mitigates spreading depolarization in human neocortical slices and prevents acute dendritic injury in the ischemic rodent neocortex.

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    W Christopher Risher

    Full Text Available Spreading depolarizations that occur in patients with malignant stroke, subarachnoid/intracranial hemorrhage, and traumatic brain injury are known to facilitate neuronal damage in metabolically compromised brain tissue. The dramatic failure of brain ion homeostasis caused by propagating spreading depolarizations results in neuronal and astroglial swelling. In essence, swelling is the initial response and a sign of the acute neuronal injury that follows if energy deprivation is maintained. Choosing spreading depolarizations as a target for therapeutic intervention, we have used human brain slices and in vivo real-time two-photon laser scanning microscopy in the mouse neocortex to study potentially useful therapeutics against spreading depolarization-induced injury.We have shown that anoxic or terminal depolarization, a spreading depolarization wave ignited in the ischemic core where neurons cannot repolarize, can be evoked in human slices from pediatric brains during simulated ischemia induced by oxygen/glucose deprivation or by exposure to ouabain. Changes in light transmittance (LT tracked terminal depolarization in time and space. Though spreading depolarizations are notoriously difficult to block, terminal depolarization onset was delayed by dibucaine, a local amide anesthetic and sodium channel blocker. Remarkably, the occurrence of ouabain-induced terminal depolarization was delayed at a concentration of 1 µM that preserves synaptic function. Moreover, in vivo two-photon imaging in the penumbra revealed that, though spreading depolarizations did still occur, spreading depolarization-induced dendritic injury was inhibited by dibucaine administered intravenously at 2.5 mg/kg in a mouse stroke model.Dibucaine mitigated the effects of spreading depolarization at a concentration that could be well-tolerated therapeutically. Hence, dibucaine is a promising candidate to protect the brain from ischemic injury with an approach that does not rely on

  3. Biomechanical forces promote embryonic haematopoiesis

    Science.gov (United States)

    Adamo, Luigi; Naveiras, Olaia; Wenzel, Pamela L.; McKinney-Freeman, Shannon; Mack, Peter J.; Gracia-Sancho, Jorge; Suchy-Dicey, Astrid; Yoshimoto, Momoko; Lensch, M. William; Yoder, Mervin C.; García-Cardeña, Guillermo; Daley, George Q.

    2009-01-01

    Biomechanical forces are emerging as critical regulators of embryogenesis, particularly in the developing cardiovascular system1,2. After initiation of the heartbeat in vertebrates, cells lining the ventral aspect of the dorsal aorta, the placental vessels, and the umbilical and vitelline arteries initiate expression of the transcription factor Runx1 (refs 3–5), a master regulator of haematopoiesis, and give rise to haematopoietic cells4. It remains unknown whether the biomechanical forces imposed on the vascular wall at this developmental stage act as a determinant of haematopoietic potential6. Here, using mouse embryonic stem cells differentiated in vitro, we show that fluid shear stress increases the expression of Runx1 in CD41+c-Kit+ haematopoietic progenitor cells7,concomitantly augmenting their haematopoietic colony-forming potential. Moreover, we find that shear stress increases haematopoietic colony-forming potential and expression of haematopoietic markers in the paraaortic splanchnopleura/aorta–gonads–mesonephros of mouse embryos and that abrogation of nitric oxide, a mediator of shear-stress-induced signalling8, compromises haematopoietic potential in vitro and in vivo. Collectively, these data reveal a critical role for biomechanical forces in haematopoietic development. PMID:19440194

  4. Generation of Pax6-IRES-EGFP knock-in mouse via the cloning-free CRISPR/Cas9 system to reliably visualize neurodevelopmental dynamics.

    Science.gov (United States)

    Inoue, Yukiko U; Morimoto, Yuki; Hoshino, Mikio; Inoue, Takayoshi

    2018-07-01

    Pax6 encodes a transcription factor that plays pivotal roles in eye development, early brain patterning, neocortical arealization, and so forth. Visualization of Pax6 expression dynamics in these events could offer numerous advantages to neurodevelopmental studies. While CRISPR/Cas9 system has dramatically accelerated one-step generation of knock-out mouse, establishment of gene-cassette knock-in mouse via zygote injection has been considered insufficient due to its low efficiency. Recently, an improved CRISPR/Cas9 system for effective gene-cassette knock-in has been reported, where the native form of guide RNAs (crRNA and tracrRNA) assembled with recombinant Cas9 protein are directly delivered into mouse fertilized eggs. Here we apply this strategy to insert IRES-EGFP-pA cassette into Pax6 locus and achieve efficient targeted insertions of the 1.8 kb reporter gene. In Pax6-IRES-EGFP mouse we have generated, EGFP-positive cells reside in the eyes and cerebellum as endogenous Pax6 expressing cells at postnatal day 2. At the early embryonic stages when the embryos are transparent, EGFP-positive regions can be easily identified without PCR-based genotyping, precisely recapitulating the endogenous Pax6 expression patterns. Remarkably, at E12.5, the graded expression patterns of Pax6 in the developing neocortex now become recognizable in our knock-in mice, serving a sufficiently sensitive and useful tool to precisely visualize neurodevelopmental processes. Copyright © 2018 Elsevier B.V. and Japan Neuroscience Society. All rights reserved.

  5. Cytokine signalling in embryonic stem cells

    DEFF Research Database (Denmark)

    Kristensen, David Møbjerg; Kalisz, Mark; Nielsen, Jens Høiriis

    2006-01-01

    Cytokines play a central role in maintaining self-renewal in mouse embryonic stem (ES) cells through a member of the interleukin-6 type cytokine family termed leukemia inhibitory factor (LIF). LIF activates the JAK-STAT3 pathway through the class I cytokine receptor gp130, which forms a trimeric...... pathways seem to converge on c-myc as a common target to promote self-renewal. Whereas LIF does not seem to stimulate self-renewal in human embryonic stem cells it cannot be excluded that other cytokines are involved. The pleiotropic actions of the increasing number of cytokines and receptors signalling...... via JAKs, STATs and SOCS exhibit considerable redundancy, compensation and plasticity in stem cells in accordance with the view that stem cells are governed by quantitative variations in strength and duration of signalling events known from other cell types rather than qualitatively different stem...

  6. Stepwise development of hematopoietic stem cells from embryonic stem cells.

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    Kenji Matsumoto

    Full Text Available The cellular ontogeny of hematopoietic stem cells (HSCs remains poorly understood because their isolation from and their identification in early developing small embryos are difficult. We attempted to dissect early developmental stages of HSCs using an in vitro mouse embryonic stem cell (ESC differentiation system combined with inducible HOXB4 expression. Here we report the identification of pre-HSCs and an embryonic type of HSCs (embryonic HSCs as intermediate cells between ESCs and HSCs. Both pre-HSCs and embryonic HSCs were isolated by their c-Kit(+CD41(+CD45(- phenotype. Pre-HSCs did not engraft in irradiated adult mice. After co-culture with OP9 stromal cells and conditional expression of HOXB4, pre-HSCs gave rise to embryonic HSCs capable of engraftment and long-term reconstitution in irradiated adult mice. Blast colony assays revealed that most hemangioblast activity was detected apart from the pre-HSC population, implying the early divergence of pre-HSCs from hemangioblasts. Gene expression profiling suggests that a particular set of transcripts closely associated with adult HSCs is involved in the transition of pre-HSC to embryonic HSCs. We propose an HSC developmental model in which pre-HSCs and embryonic HSCs sequentially give rise to adult types of HSCs in a stepwise manner.

  7. Selective elimination of intracortically projecting neurons of the rat neocortex by prenatal x-irradiation

    International Nuclear Information System (INIS)

    Jensen, K.F.

    1981-01-01

    The development of new racing methods has suggested that there are species differences in the extent of the contribution of the different layers of the neocortex to the callosal projection. The present investigation has utilized prenatal x-irradiation to selectively eliminate the late forming neurons of the supragranular layers of the rat neocortex. The reduction in the neuronal population of the supragranular layers closely parallels the reduction in the corpus callosum. These results indicate that the primary source of neurons of the callosal projection, are the late forming neurons of the supragranular layers. Thus, the current results suggest that low dose prenatal x-irradiation may be used to evaluate important developmental events in the formation of neocortical circuitry

  8. Explicit logic circuits predict local properties of the neocortex's physiology and anatomy.

    Directory of Open Access Journals (Sweden)

    Lane Yoder

    Full Text Available BACKGROUND: Two previous articles proposed an explicit model of how the brain processes information by its organization of synaptic connections. The family of logic circuits was shown to generate neural correlates of complex psychophysical phenomena in different sensory systems. METHODOLOGY/PRINCIPAL FINDINGS: Here it is shown that the most cost-effective architectures for these networks produce correlates of electrophysiological brain phenomena and predict major aspects of the anatomical structure and physiological organization of the neocortex. The logic circuits are markedly efficient in several respects and provide the foundation for all of the brain's combinational processing of information. CONCLUSIONS/SIGNIFICANCE: At the local level, these networks account for much of the physical structure of the neocortex as well its organization of synaptic connections. Electronic implementations of the logic circuits may be more efficient than current electronic logic arrays in generating both Boolean and fuzzy logic.

  9. Effects of different feeder layers on culture of bovine embryonic stem cell-like cells in vitro

    OpenAIRE

    Cong, Shan; Cao, Guifang; Liu, Dongjun

    2014-01-01

    To find a suitable feeder layer is important for successful culture conditions of bovine embryonic stem cell-like cells. In this study, expression of pluripotency-related genes OCT4, SOX2 and NANOG in bovine embryonic stem cell-like cells on mouse embryonic fibroblast feeder layers at 1–5 passages were monitored in order to identify the possible reason that bovine embryonic stem cell-like cells could not continue growth and passage. Here, we developed two novel feeder layers, mixed embryonic ...

  10. Statistical theory of synaptic connectivity in the neocortex

    Science.gov (United States)

    Escobar, Gina

    Learning and long-term memory rely on plasticity of neural circuits. In adult cerebral cortex plasticity can be mediated by modulation of existing synapses and structural reorganization of circuits through growth and retraction of dendritic spines. In the first part of this thesis, we describe a theoretical framework for the analysis of spine remodeling plasticity. New synaptic contacts appear in the neuropil where gaps between axonal and dendritic branches can be bridged by dendritic spines. Such sites are termed potential synapses. We derive expressions for the densities of potential synapses in the neuropil. We calculate the ratio of actual to potential synapses, called the connectivity fraction, and use it to find the number of structurally different circuits attainable with spine remodeling. These parameters are calculated in four systems: mouse occipital cortex, rat hippocampal area CA1, monkey primary visual (V1), and human temporal cortex. The neurogeometric results indicate that a dendritic spine can choose among an average of 4-7 potential targets in rodents, while in primates it can choose from 10-20 potential targets. The potential of the neuropil to undergo circuit remodeling is found to be highest in rat CA1 (4.9-6.0 nats/mum 3) and lowest in monkey V1 (0.9-1.0 nats/mum3). We evaluate the lower bound of neuron selectivity in the choice of synaptic partners and find that post-synaptic excitatory neurons in rodents make synaptic contacts with more than 21-30% of pre-synaptic axons encountered with new spine growth. Primate neurons appear to be more selective, making synaptic connections with more than 7-15% of encountered axons. Another plasticity mechanism is included in the second part of this work: long-term potentiation and depression of excitatory synaptic connections. Because synaptic strength is correlated with the size of the synapse, the former can be inferred from the distribution of spine head volumes. To this end we analyze and compare 166

  11. Dissecting human cerebral organoids and fetal neocortex using single-cell RNAseq

    Science.gov (United States)

    Treutlein, Barbara

    Cerebral organoids - three-dimensional cultures of human cerebral tissue derived from pluripotent stem cells - have emerged as models of human cortical development. However, the extent to which in vitro organoid systems recapitulate neural progenitor cell proliferation and neuronal differentiation programs observed in vivo remains unclear. Here we use single-cell RNA sequencing (scRNA-seq) to dissect and compare cell composition and progenitor-to-neuron lineage relationships in human cerebral organoids and fetal neocortex. Covariation network analysis using the fetal neocortex data reveals known and novel interactions among genes central to neural progenitor proliferation and neuronal differentiation. In the organoid, we detect diverse progenitors and differentiated cell types of neuronal and mesenchymal lineages, and identify cells that derived from regions resembling the fetal neocortex. We find that these organoid cortical cells use gene expression programs remarkably similar to those of the fetal tissue in order to organize into cerebral cortex-like regions. Our comparison of in vivo and in vitro cortical single cell transcriptomes illuminates the genetic features underlying human cortical development that can be studied in organoid cultures.

  12. Increased apoptosis and DNA double-strand breaks in the embryonic mouse brain in response to very low-dose X-rays but not 50 Hz magnetic fields

    Science.gov (United States)

    Saha, Shreya; Woodbine, Lisa; Haines, Jackie; Coster, Margaret; Ricket, Nicole; Barazzuol, Lara; Ainsbury, Elizabeth; Sienkiewicz, Zenon; Jeggo, Penny

    2014-01-01

    The use of X-rays for medical diagnosis is enhancing exposure to low radiation doses. Exposure to extremely low-frequency electromagnetic or magnetic fields is also increasing. Epidemiological studies show consistent associations of childhood leukaemia with exposure to magnetic fields but any causal relationship is unclear. A limitation in assessing the consequence of such exposure is the availability of sensitive assays. The embryonic neuronal stem and progenitor cell compartments are radiosensitive tissues. Using sensitive assays, we report a statistically significant increase in DNA double-strand break (DSB) formation and apoptosis in the embryonic neuronal stem cell compartment following in utero exposure to 10–200 mGy X-rays. Both endpoints show a linear response. We also show that DSB repair is delayed following exposure to doses below 50 mGy compared with 100 mGy. Thus, we demonstrate in vivo consequences of low-dose radiation. In contrast to these impacts, we did not observe any significant induction of DSBs or apoptosis following exposure to 50 Hz magnetic fields (100 or 300 µT). We conclude that any DSB induction by treatment with magnetic fields is lower than following exposure to 10 mGy X-rays. For comparison, certain procedures involving computed tomography scanning are equivalent to 1–5 mGy X-rays. PMID:25209403

  13. Increased apoptosis and DNA double-strand breaks in the embryonic mouse brain in response to very low-dose X-rays but not 50 Hz magnetic fields.

    Science.gov (United States)

    Saha, Shreya; Woodbine, Lisa; Haines, Jackie; Coster, Margaret; Ricket, Nicole; Barazzuol, Lara; Ainsbury, Elizabeth; Sienkiewicz, Zenon; Jeggo, Penny

    2014-11-06

    The use of X-rays for medical diagnosis is enhancing exposure to low radiation doses. Exposure to extremely low-frequency electromagnetic or magnetic fields is also increasing. Epidemiological studies show consistent associations of childhood leukaemia with exposure to magnetic fields but any causal relationship is unclear. A limitation in assessing the consequence of such exposure is the availability of sensitive assays. The embryonic neuronal stem and progenitor cell compartments are radiosensitive tissues. Using sensitive assays, we report a statistically significant increase in DNA double-strand break (DSB) formation and apoptosis in the embryonic neuronal stem cell compartment following in utero exposure to 10-200 mGy X-rays. Both endpoints show a linear response. We also show that DSB repair is delayed following exposure to doses below 50 mGy compared with 100 mGy. Thus, we demonstrate in vivo consequences of low-dose radiation. In contrast to these impacts, we did not observe any significant induction of DSBs or apoptosis following exposure to 50 Hz magnetic fields (100 or 300 µT). We conclude that any DSB induction by treatment with magnetic fields is lower than following exposure to 10 mGy X-rays. For comparison, certain procedures involving computed tomography scanning are equivalent to 1-5 mGy X-rays.

  14. Porcine embryonic stem cells

    DEFF Research Database (Denmark)

    Hall, Vanessa Jane

    2008-01-01

    The development of porcine embryonic stem cell lines (pESC) has received renewed interest given the advances being made in the production of immunocompatible transgenic pigs. However, difficulties are evident in the production of pESCs in-vitro. This may largely be attributable to differences...

  15. Do embryonic polar bodies commit suicide?

    Science.gov (United States)

    Fabian, Dušan; Čikoš, Štefan; Rehák, Pavol; Koppel, Juraj

    2014-02-01

    The extrusion and elimination of unnecessary gametic/embryonic material is one of the key events that determines the success of further development in all living organisms. Oocytes produce the first polar body to fulfill the maturation process just before ovulation, and release the second polar body immediately after fertilization. The aim of this study was to compile a physiological overview of elimination of polar bodies during early preimplantation development in mice. Our results show that three-quarters of the first polar bodies were lost even at the zygotic stage; the 4-cell stage embryos contained only one (second) polar body, and the elimination of second polar bodies proceeded continuously during later development. Both first and second polar bodies showed several typical features of apoptosis: phosphatidylserine redistribution (observed for the first time in the first polar body), specific DNA degradation, condensed nuclear morphology, and inability to exclude cationic dye from the nucleus during the terminal stage of the apoptotic process. Caspase-3 activity was recorded only in the second polar body. From the morphological point of view, mouse polar bodies acted very similarly to damaged embryonic cells which have lost contact with their neighboring blastomeres. In conclusion, polar bodies possess all the molecular equipment necessary for triggering and executing an active suicide process. Furthermore, similarly as in dying embryonic cells, stressing external conditions (culture in vitro) might accelerate and increase the incidence of apoptotic elimination of the polar bodies in embryos.

  16. Function of JARID2 in bovines during early embryonic development

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    Yao Fu

    2017-12-01

    Full Text Available Histone lysine modifications are important epigenetic modifications in early embryonic development. JARID2, which is a member of the jumonji demethylase protein family, is a regulator of early embryonic development and can regulate mouse development and embryonic stem cell (ESC differentiation by modifying histone lysines. JARID2 can affect early embryonic development by regulating the methylation level of H3K27me3, which is closely related to normal early embryonic development. To investigate the expression pattern of JARID2 and the effect of JARID2-induced H3K27 methylation in bovine oocytes and early embryonic stages, JARID2 mRNA expression and localization were detected in bovine oocytes and early embryos via qRT-PCR and immunofluorescence in the present study. The results showed that JARID2 is highly expressed in the germinal vesicle (GV, MII, 2-cell, 4-cell, 8-cell, 16-cell and blastocyst stages, but the relative expression level of JARID2 in bovine GV oocytes is significantly lower than that at other oocyte/embryonic stages (p < 0.05, and JARID2 is expressed primarily in the nucleus. We next detected the mRNA expression levels of embryonic development-related genes (OCT4, SOX2 and c-myc after JARID2 knockdown through JARID2-2830-siRNA microinjection to investigate the molecularpathwayunderlying the regulation of H3K27me3 by JARID2 during early embryonic development. The results showed that the relative expression levels of these genes in 2-cell embryos weresignificantly higher than those in the blastocyst stage, and expression levels were significantly increased after JARID2 knockdown. In summary, the present study identified the expression pattern of JARID2 in bovine oocytes and at each early embryonic stage, and the results suggest that JARID2 plays a key role in early embryonic development by regulating the expression of OCT4, SOX2 and c-myc via modification of H3K27me3 expression. This work provides new data for improvements in the

  17. Long-range GABAergic connections distributed throughout the neocortex and their possible function

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    Nobuaki eTamamaki

    2010-12-01

    Full Text Available Features and functions of long range GABAergic projection neurons in the developing cerebral cortex have been reported previously, although until now their significance in the adult cerebral cortex has remained uncertain. The septo-hippocampal circuit is one exception – in this system, long range mature GABAergic projection neurons have been well analyzed and their contribution to the generation of theta-oscillatory behavior in the hippocampus has been documented. To have a clue to the function of the GABAergic projection neurons in the neocortex, we view the long range GABAergic projections those participating in the cortico-cortical, cortico-fugal, and afferent projections in the cerebral cortex. Then, we consider the possibility that the GABAergic projection neurons are involved in the generation, modification, and/or synchronization of oscillations in mature neocortical neuron activity. When markers that identify the GABAergic projection neurons are examined in anatomical and developmental studies, it is clear that neuronal NO synthetase (nNOS-immunoreactivity can readily identify GABAergic projection fibers (i.e. those longer than 1.5 mm. To elucidate the role of the GABAergic projection neurons in the neocortex, it will be necessary to clarify the network constructed by nNOS-positive GABAergic projection neurons and their postsynaptic targets. Thus, our long-range goals will be to label and manipulate (including deleting the GABAergic projection neurons using genetic tools driven by a nNOS promoter. We recognize that this may be a complex endeavor, as most excitatory neurons in the murine neocortex express nNOS transiently. Nevertheless, additional studies characterizing long range GABAergic projection neurons will have great value to the overall understanding of mature cortical function.

  18. Roles of taurine-mediated tonic GABAA receptor activation in the radial migration of neurons in the fetal mouse cerebral cortex

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    Tomonori eFurukawa

    2014-03-01

    Full Text Available γ-Aminobutyric acid (GABA depolarizes embryonic cerebrocortical neurons and continuous activation of the GABAA receptor (GABAAR contributes to their tonic depolarization. Although multiple reports have demonstrated a role of GABAAR activation in neocortical development, including in migration, most of these studies have used pharmacological blockers. Herein, we performed in utero electroporation in GABA synthesis-lacking homozygous GAD67-GFP knock-in mice (GAD67GFP/GFP to label neurons born in the ventricular zone. Three days after electroporation, there were no differences in the distribution of labeled cells between the genotypes. The dose-response properties of cells labeled to detect GABA were equivalent among genotypes. However, continuous blockade of GABAAR with the GABAAR antagonist SR95531 accelerated radial migration. This effect of GABAAR blockade in GAD67GFP/GFP mice suggested a role for alternative endogenous GABAAR agonists. Thus, we tested the role of taurine, which is derived from maternal blood but is abundant in the fetal brain. The taurine-evoked currents in labeled cells were mediated by GABAAR. Taurine uptake was blocked by a taurine transporter inhibitor, 2-(guanidinoethanesulfonic acid (GES, and taurine release was blocked by a volume-sensitive anion channel blocker, 4-(2-butyl-6,7-dichlor-2-cyclopentylindan-1-on-5-yl oxobutyric acid (DCPIB, as examined through high-performance liquid chromatography (HPLC. GES increased the extracellular taurine concentration and induced an inward shift of the holding current, which was reversed by SR95531. In a taurine-deficient mouse model, the GABAAR-mediated tonic currents were greatly reduced, and radial migration was accelerated. As the tonic currents were equivalent among the genotypes of GAD67-GFP knock-in mice, taurine, rather than GABA, might play a major role as an endogenous agonist of embryonic tonic GABAAR conductance, regulating the radial migration of neurons in the

  19. Polycomb enables primitive endoderm lineage priming in embryonic stem cells

    DEFF Research Database (Denmark)

    Illingworth, Robert S; Hölzenspies, Jurriaan J; Roske, Fabian V

    2016-01-01

    Mouse embryonic stem cells (ESCs), like the blastocyst from which they are derived, contain precursors of the epiblast (Epi) and primitive endoderm (PrEn) lineages. While transient in vivo, these precursor populations readily interconvert in vitro. We show that altered transcription is the driver...... polycomb with dynamic changes in transcription and stalled lineage commitment, allowing cells to explore alternative choices prior to a definitive decision....

  20. Somatic donor cell type correlates with embryonic, but not extra-embryonic, gene expression in postimplantation cloned embryos.

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    Ryutaro Hirasawa

    Full Text Available The great majority of embryos generated by somatic cell nuclear transfer (SCNT display defined abnormal phenotypes after implantation, such as an increased likelihood of death and abnormal placentation. To gain better insight into the underlying mechanisms, we analyzed genome-wide gene expression profiles of day 6.5 postimplantation mouse embryos cloned from three different cell types (cumulus cells, neonatal Sertoli cells and fibroblasts. The embryos retrieved from the uteri were separated into embryonic (epiblast and extraembryonic (extraembryonic ectoderm and ectoplacental cone tissues and were subjected to gene microarray analysis. Genotype- and sex-matched embryos produced by in vitro fertilization were used as controls. Principal component analysis revealed that whereas the gene expression patterns in the embryonic tissues varied according to the donor cell type, those in extraembryonic tissues were relatively consistent across all groups. Within each group, the embryonic tissues had more differentially expressed genes (DEGs (>2-fold vs. controls than did the extraembryonic tissues (P<1.0 × 10(-26. In the embryonic tissues, one of the common abnormalities was upregulation of Dlk1, a paternally imprinted gene. This might be a potential cause of the occasional placenta-only conceptuses seen in SCNT-generated mouse embryos (1-5% per embryos transferred in our laboratory, because dysregulation of the same gene is known to cause developmental failure of embryos derived from induced pluripotent stem cells. There were also some DEGs in the extraembryonic tissues, which might explain the poor development of SCNT-derived placentas at early stages. These findings suggest that SCNT affects the embryonic and extraembryonic development differentially and might cause further deterioration in the embryonic lineage in a donor cell-specific manner. This could explain donor cell-dependent variations in cloning efficiency using SCNT.

  1. Direction of Amygdala-Neocortex Interaction During Dynamic Facial Expression Processing.

    Science.gov (United States)

    Sato, Wataru; Kochiyama, Takanori; Uono, Shota; Yoshikawa, Sakiko; Toichi, Motomi

    2017-03-01

    Dynamic facial expressions of emotion strongly elicit multifaceted emotional, perceptual, cognitive, and motor responses. Neuroimaging studies revealed that some subcortical (e.g., amygdala) and neocortical (e.g., superior temporal sulcus and inferior frontal gyrus) brain regions and their functional interaction were involved in processing dynamic facial expressions. However, the direction of the functional interaction between the amygdala and the neocortex remains unknown. To investigate this issue, we re-analyzed functional magnetic resonance imaging (fMRI) data from 2 studies and magnetoencephalography (MEG) data from 1 study. First, a psychophysiological interaction analysis of the fMRI data confirmed the functional interaction between the amygdala and neocortical regions. Then, dynamic causal modeling analysis was used to compare models with forward, backward, or bidirectional effective connectivity between the amygdala and neocortical networks in the fMRI and MEG data. The results consistently supported the model of effective connectivity from the amygdala to the neocortex. Further increasing time-window analysis of the MEG demonstrated that this model was valid after 200 ms from the stimulus onset. These data suggest that emotional processing in the amygdala rapidly modulates some neocortical processing, such as perception, recognition, and motor mimicry, when observing dynamic facial expressions of emotion. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  2. Histological evidence for drug diffusion across the cerebral meninges into the underlying neocortex in rats.

    Science.gov (United States)

    Ludvig, Nandor; Sheffield, Lynette G; Tang, Hai M; Baptiste, Shirn L; Devinsky, Orrin; Kuzniecky, Ruben I

    2008-01-10

    Transmeningeal pharmacotherapy has been proposed to treat neurological disorders with localized pathology, such as intractable focal epilepsy. As a step toward understanding the diffusion and intracortical spread of transmeningeally delivered drugs, the present study used histological methods to determine the extent to which a marker compound, N-methyl-D-aspartate (NMDA), can diffuse into the neocortex through the meninges. Rats were implanted with bilateral parietal cortical epidural cups filled with 50 mM NMDA on the right side and artificial cerebrospinal fluid (ACSF) in the contralateral side. After 24 h, the histological effects of these treatments were evaluated using cresyl violet (Nissl) staining. The epidural NMDA exposure caused neuronal loss that in most animals extended from the pial surface through layer V. The area indicated by this neuronal loss was localized to the neocortical region underlying the epidural cup. These results suggest that NMDA-like, water soluble, small molecules can diffuse through the subdural/subarachnoid space into the underlying neocortex and spread in a limited fashion, close to the meningeal penetration site.

  3. Carcino-Embryonic Antigen

    International Nuclear Information System (INIS)

    Akute, O.

    1999-02-01

    Tumour marker analysis has increased our understanding of the presence of tumours in the body. Carcino-embryonic antigen, CEA, is one of the best studied tumour markers and has proved an ideal diagnostic adjuvant. It has helped in quantifying the amount of disease present in a patient and thence to make accurate prognosis on the various diagnosed ailments. At UCH, it is observed that there is an increase in cancer related ailments and therefore the need for early diagnosis is more compelling in our environment to mitigate future cost of managing advanced manifestation

  4. Differentiation of embryonic stem cells towards hematopoietic cells: progress and pitfalls.

    Science.gov (United States)

    Tian, Xinghui; Kaufman, Dan S

    2008-07-01

    Hematopoietic development from embryonic stem cells has been one of the most productive areas of stem cell biology. Recent studies have progressed from work with mouse to human embryonic stem cells. Strategies to produce defined blood cell populations can be used to better understand normal and abnormal hematopoiesis, as well as potentially improve the generation of hematopoietic cells with therapeutic potential. Molecular profiling, phenotypic and functional analyses have all been utilized to demonstrate that hematopoietic cells derived from embryonic stem cells most closely represent a stage of hematopoiesis that occurs at embryonic/fetal developmental stages. Generation of hematopoietic stem/progenitor cells comparable to hematopoietic stem cells found in the adult sources, such as bone marrow and cord blood, still remains challenging. However, genetic manipulation of intrinsic factors during hematopoietic differentiation has proven a suitable approach to induce adult definitive hematopoiesis from embryonic stem cells. Concrete evidence has shown that embryonic stem cells provide a powerful approach to study the early stage of hematopoiesis. Multiple hematopoietic lineages can be generated from embryonic stem cells, although most of the evidence suggests that hematopoietic development from embryonic stem cells mimics an embryonic/fetal stage of hematopoiesis.

  5. High glucose suppresses embryonic stem cell differentiation into neural lineage cells

    OpenAIRE

    Yang, Penghua; Shen, Wei-bin; Reece, E. Albert; Chen, Xi; Yang, Peixin

    2016-01-01

    Abnormal neurogenesis occurs during embryonic development in human diabetic pregnancies and in animal models of diabetic embryopathy. Our previous studies in a mouse model of diabetic embryopathy have implicated that high glucose of maternal diabetes delays neurogenesis in the developing neuroepithelium leading to neural tube defects. However, the underlying process in high glucose-impaired neurogenesis is uncharacterized. Neurogenesis from embryonic stem (ES) cells provides a valuable model ...

  6. Bottom-Up versus Top-Down Induction of Sleep by Zolpidem Acting on Histaminergic and Neocortex Neurons

    Science.gov (United States)

    Uygun, David S.; Ye, Zhiwen; Zecharia, Anna Y.; Harding, Edward C.; Yu, Xiao; Yustos, Raquel; Vyssotski, Alexei L.; Brickley, Stephen G.

    2016-01-01

    Zolpidem, a GABAA receptor-positive modulator, is the gold-standard drug for treating insomnia. Zolpidem prolongs IPSCs to decrease sleep latency and increase sleep time, effects that depend on α2 and/or α3 subunit-containing receptors. Compared with natural NREM sleep, zolpidem also decreases the EEG power, an effect that depends on α1 subunit-containing receptors, and which may make zolpidem-induced sleep less optimal. In this paper, we investigate whether zolpidem needs to potentiate only particular GABAergic pathways to induce sleep without reducing EEG power. Mice with a knock-in F77I mutation in the GABAA receptor γ2 subunit gene are zolpidem-insensitive. Using these mice, GABAA receptors in the frontal motor neocortex and hypothalamic (tuberomammillary nucleus) histaminergic-neurons of γ2I77 mice were made selectively sensitive to zolpidem by genetically swapping the γ2I77 subunits with γ2F77 subunits. When histamine neurons were made selectively zolpidem-sensitive, systemic administration of zolpidem shortened sleep latency and increased sleep time. But in contrast to the effect of zolpidem on wild-type mice, the power in the EEG spectra of NREM sleep was not decreased, suggesting that these EEG power-reducing effects of zolpidem do not depend on reduced histamine release. Selective potentiation of GABAA receptors in the frontal cortex by systemic zolpidem administration also reduced sleep latency, but less so than for histamine neurons. These results could help with the design of new sedatives that induce a more natural sleep. SIGNIFICANCE STATEMENT Many people who find it hard to get to sleep take sedatives. Zolpidem (Ambien) is the most widely prescribed “sleeping pill.” It makes the inhibitory neurotransmitter GABA work better at its receptors throughout the brain. The sleep induced by zolpidem does not resemble natural sleep because it produces a lower power in the brain waves that occur while we are sleeping. We show using mouse genetics

  7. Disruption of the blood-brain interface in neonatal rat neocortex induces a transient expression of metallothionein in reactive astrocytes

    DEFF Research Database (Denmark)

    Penkowa, M; Moos, T

    1995-01-01

    rats were subjected to a localized freeze lesion of the neocortex of the right temporal cortex. This lesion results in a disrupted blood-brain interface, leading to extravasation of plasma proteins. From 16 h, reactive astrocytosis, defined as an increase in the number and size of cells expressing GFAP...

  8. Analysis of stability and bifurcations of fixed points and periodic solutions of a lumped model of neocortex with two delays

    NARCIS (Netherlands)

    Visser, Sid; Meijer, Hil G.E.; van Putten, Michel J.A.M.; van Gils, Stephan A.

    2012-01-01

    A lumped model of neural activity in neocortex is studied to identify regions of multi-stability of both steady states and periodic solutions. Presence of both steady states and periodic solutions is considered to correspond with epileptogenesis. The model, which consists of two delay differential

  9. Cell number, tissue thickness and protein content as measures for development and variability in cultured neocortex explants

    NARCIS (Netherlands)

    de Jong, B. M.; Ruijter, J. M.

    1989-01-01

    The development of neuronal number, explant thickness and amount of protein was studied in several series of rat neocortex explants, cultured up to 21 days in vitro (DIV). In contrast to the dimensions of the explant, which rapidly stabilized, the amount of protein showed a prolonged increase with

  10. Embryonic Toxicity of Nanoparticles

    Czech Academy of Sciences Publication Activity Database

    Celá, Petra; Veselá, Barbora; Matalová, Eva; Večeřa, Zbyněk; Buchtová, Marcela

    2014-01-01

    Roč. 199, č. 1 (2014), s. 1-23 ISSN 1422-6405 R&D Projects: GA ČR(CZ) GAP503/11/2315; GA ČR(CZ) GBP503/12/G147 Institutional support: RVO:67985904 ; RVO:68081715 Keywords : development * nanotechnology * toxicology * chicken * mouse Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.137, year: 2014

  11. Bone morphogenetic protein-2 functions as a negative regulator in the differentiation of myoblasts, but not as an inducer for the formations of cartilage and bone in mouse embryonic tongue

    Directory of Open Access Journals (Sweden)

    Suzuki Erika

    2011-07-01

    Full Text Available Abstract Background In vitro studies using the myogenic cell line C2C12 demonstrate that bone morphogenetic protein-2 (BMP-2 converts the developmental pathway of C2C12 from a myogenic cell lineage to an osteoblastic cell lineage. Further, in vivo studies using null mutation mice demonstrate that BMPs inhibit the specification of the developmental fate of myogenic progenitor cells. However, the roles of BMPs in the phases of differentiation and maturation in skeletal muscles have yet to be determined. The present study attempts to define the function of BMP-2 in the final stage of differentiation of mouse tongue myoblast. Results Recombinant BMP-2 inhibited the expressions of markers for the differentiation of skeletal muscle cells, such as myogenin, muscle creatine kinase (MCK, and fast myosin heavy chain (fMyHC, whereas BMP-2 siRNA stimulated such markers. Neither the recombinant BMP-2 nor BMP-2 siRNA altered the expressions of markers for the formation of cartilage and bone, such as osteocalcin, alkaline phosphatase (ALP, collagen II, and collagen X. Further, no formation of cartilage and bone was observed in the recombinant BMP-2-treated tongues based on Alizarin red and Alcian blue stainings. Neither recombinant BMP-2 nor BMP-2 siRNA affected the expression of inhibitor of DNA binding/differentiation 1 (Id1. The ratios of chondrogenic and osteogenic markers relative to glyceraldehyde-3-phosphate dehydrogenase (GAPDH, a house keeping gene were approximately 1000-fold lower than those of myogenic markers in the cultured tongue. Conclusions BMP-2 functions as a negative regulator for the final differentiation of tongue myoblasts, but not as an inducer for the formation of cartilage and bone in cultured tongue, probably because the genes related to myogenesis are in an activation mode, while the genes related to chondrogenesis and osteogenesis are in a silencing mode.

  12. Columnar interactions determine horizontal propagation of recurrent network activity in neocortex

    Science.gov (United States)

    Wester, Jason C.; Contreras, Diego

    2012-01-01

    The cortex is organized in vertical and horizontal circuits that determine the spatiotemporal properties of distributed cortical activity. Despite detailed knowledge of synaptic interactions among individual cells in the neocortex, little is known about the rules governing interactions among local populations. Here we used self-sustained recurrent activity generated in cortex, also known as up-states, in rat thalamocortical slices in vitro to understand interactions among laminar and horizontal circuits. By means of intracellular recordings and fast optical imaging with voltage sensitive dyes, we show that single thalamic inputs activate the cortical column in a preferential L4→L2/3→L5 sequence, followed by horizontal propagation with a leading front in supra and infragranular layers. To understand the laminar and columnar interactions, we used focal injections of TTX to block activity in small local populations, while preserving functional connectivity in the rest of the network. We show that L2/3 alone, without underlying L5, does not generate self-sustained activity and is inefficient propagating activity horizontally. In contrast, L5 sustains activity in the absence of L2/3 and is necessary and sufficient to propagate activity horizontally. However, loss of L2/3 delays horizontal propagation via L5. Finally, L5 amplifies activity in L2/3. Our results show for the first time that columnar interactions between supra and infragranular layers are required for the normal propagation of activity in the neocortex. Our data suggest that supra and infragranular circuits with their specific and complex set of inputs and outputs, work in tandem to determine the patterns of cortical activation observed in vivo. PMID:22514308

  13. Monoaminergic Control of Cellular Glucose Utilization by Glycogenolysis in Neocortex and Hippocampus.

    Science.gov (United States)

    DiNuzzo, Mauro; Giove, Federico; Maraviglia, Bruno; Mangia, Silvia

    2015-12-01

    Brainstem nuclei are the principal sites of monoamine (MA) innervation to major forebrain structures. In the cortical grey matter, increased secretion of MA neuromodulators occurs in response to a wealth of environmental and homeostatic challenges, whose onset is associated with rapid, preparatory changes in neural activity as well as with increases in energy metabolism. Blood-borne glucose is the main substrate for energy production in the brain. Once entered the tissue, interstitial glucose is equally accessible to neurons and astrocytes, the two cell types accounting for most of cellular volume and energy metabolism in neocortex and hippocampus. Astrocytes also store substantial amounts of glycogen, but non-stimulated glycogen turnover is very small. The rate of cellular glucose utilization in the brain is largely determined by hexokinase, which under basal conditions is more than 90 % inhibited by its product glucose-6-phosphate (Glc-6-P). During rapid increases in energy demand, glycogen is a primary candidate in modulating the intracellular level of Glc-6-P, which can occur only in astrocytes. Glycogenolysis can produce Glc-6-P at a rate higher than uptake and phosphorylation of glucose. MA neurotransmitter are released extrasinaptically by brainstem neurons projecting to neocortex and hippocampus, thus activating MA receptors located on both neuronal and astrocytic plasma membrane. Importantly, MAs are glycogenolytic agents and thus they are exquisitely suitable for regulation of astrocytic Glc-6-P concentration, upstream substrate flow through hexokinase and hence cellular glucose uptake. Conforming to such mechanism, Gerald A. Dienel and Nancy F. Cruz recently suggested that activation of noradrenergic locus coeruleus might reversibly block astrocytic glucose uptake by stimulating glycogenolysis in these cells, thereby anticipating the rise in glucose need by active neurons. In this paper, we further develop the idea that the whole monoaminergic system

  14. Endonucleases : new tools to edit the mouse genome

    NARCIS (Netherlands)

    Wijshake, Tobias; Baker, Darren J.; van de Sluis, Bart

    2014-01-01

    Mouse transgenesis has been instrumental in determining the function of genes in the pathophysiology of human diseases and modification of genes by homologous recombination in mouse embryonic stem cells remains a widely used technology. However, this approach harbors a number of disadvantages, as it

  15. PTBP1 is required for embryonic development before gastrulation.

    Science.gov (United States)

    Suckale, Jakob; Wendling, Olivia; Masjkur, Jimmy; Jäger, Melanie; Münster, Carla; Anastassiadis, Konstantinos; Stewart, A Francis; Solimena, Michele

    2011-02-17

    Polypyrimidine-tract binding protein 1 (PTBP1) is an important cellular regulator of messenger RNAs influencing the alternative splicing profile of a cell as well as its mRNA stability, location and translation. In addition, it is diverted by some viruses to facilitate their replication. Here, we used a novel PTBP1 knockout mouse to analyse the tissue expression pattern of PTBP1 as well as the effect of its complete removal during development. We found evidence of strong PTBP1 expression in embryonic stem cells and throughout embryonic development, especially in the developing brain and spinal cord, the olfactory and auditory systems, the heart, the liver, the kidney, the brown fat and cartilage primordia. This widespread distribution points towards a role of PTBP1 during embryonic development. Homozygous offspring, identified by PCR and immunofluorescence, were able to implant but were arrested or retarded in growth. At day 7.5 of embryonic development (E7.5) the null mutants were about 5x smaller than the control littermates and the gap in body size widened with time. At mid-gestation, all homozygous embryos were resorbed/degraded. No homozygous mice were genotyped at E12 and the age of weaning. Embryos lacking PTBP1 did not display differentiation into the 3 germ layers and cavitation of the epiblast, which are hallmarks of gastrulation. In addition, homozygous mutants displayed malformed ectoplacental cones and yolk sacs, both early supportive structure of the embryo proper. We conclude that PTBP1 is not required for the earliest isovolumetric divisions and differentiation steps of the zygote up to the formation of the blastocyst. However, further post-implantation development requires PTBP1 and stalls in homozygous null animals with a phenotype of dramatically reduced size and aberration in embryonic and extra-embryonic structures.

  16. In vivo characterization of the electrophysiological and astrocytic responses to a silicon neuroprobe implanted in the mouse neocortex.

    Science.gov (United States)

    Mols, Katrien; Musa, Silke; Nuttin, Bart; Lagae, Liesbet; Bonin, Vincent

    2017-11-15

    Silicon neuroprobes hold great potential for studies of large-scale neural activity and brain computer interfaces, but data on brain response in chronic implants is limited. Here we explored with in vivo cellular imaging the response to multisite silicon probes for neural recordings. We tested a chronic implant for mice consisting of a CMOS-compatible silicon probe rigidly implanted in the cortex under a cranial imaging window. Multiunit recordings of cortical neurons with the implant showed no degradation of electrophysiological signals weeks after implantation (mean spike and noise amplitudes of 186 ± 42 µV pp and 16 ± 3.2 µV rms , respectively, n = 5 mice). Two-photon imaging through the cranial window allowed longitudinal monitoring of fluorescently-labeled astrocytes from the second week post implantation for 8 weeks (n = 3 mice). The imaging showed a local increase in astrocyte-related fluorescence that remained stable from the second to the tenth week post implantation. These results demonstrate that, in a standard electrophysiology protocol in mice, rigidly implanted silicon probes can provide good short to medium term chronic recording performance with a limited astrocyte inflammatory response. The precise factors influencing the response to silicon probe implants remain to be elucidated.

  17. Single cell electroporation for longitudinal imaging of synaptic structure and function in the adult mouse neocortex in vivo

    Directory of Open Access Journals (Sweden)

    Stephane ePages

    2015-04-01

    Full Text Available Longitudinal imaging studies of neuronal structures in vivo have revealed rich dynamics in dendritic spines and axonal boutons. Spines and boutons are considered to be proxies for synapses. This implies that synapses display similar dynamics. However, spines and boutons do not always bear synapses, some may contain more than one, and dendritic shaft synapses have no clear structural proxies. In addition, synaptic strength is not always accurately revealed by just the size of these structures. Structural and functional dynamics of synapses could be studied more reliably using fluorescent synaptic proteins as markers for size and function. These proteins are often large and possibly interfere with circuit development, which renders them less suitable for conventional transfection or transgenesis methods such as viral vectors, in utero electroporation and germline transgenesis. Single cell electroporation has been shown to be a potential alternative for transfection of recombinant fluorescent proteins in adult cortical neurons. Here we provide proof of principle for the use of single cell electroporation to express and subsequently image fluorescently tagged synaptic proteins over days to weeks in vivo.

  18. Embryonic duplications in sheep.

    Science.gov (United States)

    Dennis, S M

    1975-02-01

    Twenty-seven embryonic duplications were examined during a 3-year investigation into the causes of perinatal lamb mortality. Twenty of the 27 were anomalous twins with 19 being conjoined (diplopagus 9 and heteropagus 10). The various duplications were: haloacardius acephalus 1, diprosopus 2, dicephalus 2, dipypus 3, diprosopus dipygus 1, syncephalus dipygus 1, pygopagus parasiticus 1, heteropagus dipygus 3, melodidymus 6, polyury 4, penile duplication 2, and bilateral otognathia 1. Four lambs were living and the time of death of the others was: parturient 8, and post-parturient 15. Average dry weight of the lambs was 3.35 kg (range 1.59 to 5.45 kg). Breed distribution was: Merino 77.8%, Crossbred 14.8%, Dorset Horn 3.7%, and Corriedale 3.7%. The caudal region was involved in 10 of the conjoined twins (52.6%), anterior region in 7 (36.9