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Sample records for cell differentiation regulates

  1. Regulators of Tfh cell differentiation

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    Gajendra Motiram Jogdand

    2016-11-01

    Full Text Available The follicular helper T (Tfh cells help is critical for activation of B cells, antibody class switching and germinal center formation. The Tfh cells are characterized by the expression of CXCR5, ICOS, PD-1, Bcl-6, and IL-21. They are involved in clearing infections and are adversely linked with autoimmune diseases and also have a role in viral replication as well as clearance. Tfh cells are generated from naïve CD4 T cells with sequential steps involving cytokine signaling (IL-21, IL-6, IL-12, activin A, migration and positioning in the germinal center by CXCR5, surface receptors (ICOS/ICOSL, SAP/SLAM as well as transcription factor (Bcl-6, c-Maf, STAT3 signaling and repressor miR155. On the other hand Tfh generation is negatively regulated at specific steps of Tfh generation by specific cytokine (IL-2, IL-7, surface receptor (PD-1, CTLA-4, transcription factors Blimp-1, STAT5, T-bet, KLF-2 signaling and repressor miR 146a. Interestingly, miR 17-92 and FOXO1 acts as a positive as well as a negative regulator of Tfh differentiation depending on the time of expression and disease specificity. Tfh cells are also generated from the conversion of other effector T cells as exemplified by Th1 cells converting into Tfh during viral infection. The mechanistic details of effector T cells conversion into Tfh are yet to be clear. To manipulate Tfh cells for therapeutic implication and or for effective vaccination strategies, it is important to know positive and negative regulators of Tfh generation. Hence, in this review we have highlighted and interlinked molecular signaling from cytokines, surface receptors, transcription factors, ubiquitin Ligase and miRNA as positive and negative regulators for Tfh differentiation.

  2. Biophysical regulation of stem cell differentiation.

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    Govey, Peter M; Loiselle, Alayna E; Donahue, Henry J

    2013-06-01

    Bone adaptation to its mechanical environment, from embryonic through adult life, is thought to be the product of increased osteoblastic differentiation from mesenchymal stem cells. In parallel with tissue-scale loading, these heterogeneous populations of multipotent stem cells are subject to a variety of biophysical cues within their native microenvironments. Bone marrow-derived mesenchymal stem cells-the most broadly studied source of osteoblastic progenitors-undergo osteoblastic differentiation in vitro in response to biophysical signals, including hydrostatic pressure, fluid flow and accompanying shear stress, substrate strain and stiffness, substrate topography, and electromagnetic fields. Furthermore, stem cells may be subject to indirect regulation by mechano-sensing osteocytes positioned to more readily detect these same loading-induced signals within the bone matrix. Such paracrine and juxtacrine regulation of differentiation by osteocytes occurs in vitro. Further studies are needed to confirm both direct and indirect mechanisms of biophysical regulation within the in vivo stem cell niche.

  3. Regulation of T cell differentiation and function by EZH2

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    THEODOROS KARANTANOS

    2016-05-01

    Full Text Available The enhancer of zeste homologue 2 (EZH2, one of the polycomb group (PcG proteins, is the catalytic subunit of Polycomb-repressive complex 2 (PRC2 and induces the trimethylation of the histone H3 lysine 27 (H3K27me3 promoting epigenetic gene silencing. EZH2 contains a SET domain promoting the methyltransferase activity while the three other protein components of PRC2, namely EED, SUZ12 and RpAp46/48 induce compaction of the chromatin permitting EZH2 enzymatic activity. Numerous studies highlight the role of this evolutionary conserved protein as a master regulator of differentiation in humans involved in the repression of the homeotic (Hox gene and the inactivation of X-chromosome. Through its effects in the epigenetic regulation of critical genes, EZH2 has been strongly linked to cell cycle progression, stem cell pluripotency and cancer biology. Most recently, EZH2 has been associated with hematopoietic stem cell proliferation and differentiation, thymopoiesis and lymphopoiesis. Several studies have evaluated the role of EZH2 in the regulation of T cell differentiation and plasticity as well as its implications in the development of autoimmune diseases and graft versus host disease (GvHD. In this review we will briefly summarize the current knowledge regarding the role of EZH2 in the regulation of T cell differentiation, effector function and homing in the tumor microenvironment and we will discuss possible therapeutic targeting of EZH2 in order to alter T cell immune functions.

  4. Regulation of T Cell Differentiation and Function by EZH2

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    Karantanos, Theodoros; Christofides, Anthos; Bardhan, Kankana; Li, Lequn; Boussiotis, Vassiliki A.

    2016-01-01

    The enhancer of zeste homolog 2 (EZH2), one of the polycomb-group proteins, is the catalytic subunit of Polycomb-repressive complex 2 (PRC2) and induces the trimethylation of the histone H3 lysine 27 (H3K27me3) promoting epigenetic gene silencing. EZH2 contains a SET domain promoting the methyltransferase activity, while the three other protein components of PRC2, namely EED, SUZ12, and RpAp46/48, induce compaction of the chromatin permitting EZH2 enzymatic activity. Numerous studies highlight the role of this evolutionary conserved protein as a master regulator of differentiation in humans involved in the repression of the homeotic gene and the inactivation of X-chromosome. Through its effects in the epigenetic regulation of critical genes, EZH2 has been strongly linked to cell cycle progression, stem cell pluripotency, and cancer biology, being currently at the cutting edge of research. Most recently, EZH2 has been associated with hematopoietic stem cell proliferation and differentiation, thymopoiesis and lymphopoiesis. Several studies have evaluated the role of EZH2 in the regulation of T cell differentiation and plasticity as well as its implications in the development of autoimmune diseases and graft-versus-host disease (GVHD). The aim of this review is to summarize the current knowledge regarding the role of EZH2 in the regulation of the differentiation and function of T cells focusing on possible applications in various immune-mediated conditions, including autoimmune disorders and GVHD. PMID:27199994

  5. EZH2: a pivotal regulator in controlling cell differentiation.

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    Chen, Ya-Huey; Hung, Mien-Chie; Li, Long-Yuan

    2012-01-01

    Epigenetic regulation plays an important role in stem cell self-renewal, maintenance and lineage differentiation. The epigenetic profiles of stem cells are related to their transcriptional signature. Enhancer of Zeste homlog 2 (EZH2), a catalytic subunit of epigenetic regulator Polycomb repressive complex 2 (PRC2), has been shown to be a key regulator in controlling cellular differentiation. EZH2 is a histone methyltransferase that not only methylates histone H3 on Lys 27 (H3K27me3) but also interacts with and recruits DNA methyltransferases to methylate CpG at certain EZH2 target genes to establish firm repressive chromatin structures, contributing to tumor progression and the regulation of development and lineage commitment both in embryonic stem cells (ESCs) and adult stem cells. In addition to its well-recognized epigenetic gene silencing function, EZH2 also directly methylates nonhistone targets such as the cardiac transcription factor, GATA4, resulting in attenuated GATA4 transcriptional activity and gene repression. This review addresses recent progress toward the understanding of the biological functions and regulatory mechanisms of EZH2 and its targets as well as their roles in stem cell maintenance and cell differentiation.

  6. NFIX Regulates Neural Progenitor Cell Differentiation During Hippocampal Morphogenesis

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    Heng, Yee Hsieh Evelyn; McLeay, Robert C.; Harvey, Tracey J.; Smith, Aaron G.; Barry, Guy; Cato, Kathleen; Plachez, Céline; Little, Erica; Mason, Sharon; Dixon, Chantelle; Gronostajski, Richard M.; Bailey, Timothy L.; Richards, Linda J.; Piper, Michael

    2014-01-01

    Neural progenitor cells have the ability to give rise to neurons and glia in the embryonic, postnatal and adult brain. During development, the program regulating whether these cells divide and self-renew or exit the cell cycle and differentiate is tightly controlled, and imbalances to the normal trajectory of this process can lead to severe functional consequences. However, our understanding of the molecular regulation of these fundamental events remains limited. Moreover, processes underpinning development of the postnatal neurogenic niches within the cortex remain poorly defined. Here, we demonstrate that Nuclear factor one X (NFIX) is expressed by neural progenitor cells within the embryonic hippocampus, and that progenitor cell differentiation is delayed within Nfix−/− mice. Moreover, we reveal that the morphology of the dentate gyrus in postnatal Nfix−/− mice is abnormal, with fewer subgranular zone neural progenitor cells being generated in the absence of this transcription factor. Mechanistically, we demonstrate that the progenitor cell maintenance factor Sry-related HMG box 9 (SOX9) is upregulated in the hippocampus of Nfix−/− mice and demonstrate that NFIX can repress Sox9 promoter-driven transcription. Collectively, our findings demonstrate that NFIX plays a central role in hippocampal morphogenesis, regulating the formation of neuronal and glial populations within this structure. PMID:23042739

  7. Roquin Paralogs Differentially Regulate Functional NKT Cell Subsets.

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    Drees, Christoph; Vahl, J Christoph; Bortoluzzi, Sabrina; Heger, Klaus D; Fischer, Julius C; Wunderlich, F Thomas; Peschel, Christian; Schmidt-Supprian, Marc

    2017-04-01

    NKT cells represent a small subset of glycolipid-recognizing T cells that are heavily implicated in human allergic, autoimmune, and malignant diseases. In the thymus, precursor cells recognize self-glycolipids by virtue of their semi-invariant TCR, which triggers NKT cell lineage commitment and maturation. During their development, NKT cells are polarized into the NKT1, NKT2, and NKT17 subsets, defined through their cytokine-secretion patterns and the expression of key transcription factors. However, we have largely ignored how the differentiation into the NKT cell subsets is regulated. In this article, we describe the mRNA-binding Roquin-1 and -2 proteins as central regulators of murine NKT cell fate decisions. In the thymus, T cell-specific ablation of the Roquin paralogs leads to a dramatic expansion of NKT17 cells, whereas peripheral mature NKT cells are essentially absent. Roquin-1/2-deficient NKT17 cells show exaggerated lineage-specific expression of nearly all NKT17-defining proteins tested. We show through mixed bone marrow chimera experiments that NKT17 polarization is mediated through cell-intrinsic mechanisms early during NKT cell development. In contrast, the loss of peripheral NKT cells is due to cell-extrinsic factors. Surprisingly, Roquin paralog-deficient NKT cells are, in striking contrast to conventional T cells, compromised in their ability to secrete cytokines. Altogether, we show that Roquin paralogs regulate the development and function of NKT cell subsets in the thymus and periphery. Copyright © 2017 by The American Association of Immunologists, Inc.

  8. Zfp206 regulates ES cell gene expression and differentiation.

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    Zhang, Wen; Walker, Emily; Tamplin, Owen J; Rossant, Janet; Stanford, William L; Hughes, Timothy R

    2006-01-01

    Understanding transcriptional regulation in early developmental stages is fundamental to understanding mammalian development and embryonic stem (ES) cell properties. Expression surveys suggest that the putative SCAN-Zinc finger transcription factor Zfp206 is expressed specifically in ES cells [Zhang,W., Morris,Q.D., Chang,R., Shai,O., Bakowski,M.A., Mitsakakis,N., Mohammad,N., Robinson,M.D., Zirngibl,R., Somogyi,E. et al., (2004) J. Biol., 3, 21; Brandenberger,R., Wei,H., Zhang,S., Lei,S., Murage,J., Fisk,G.J., Li,Y., Xu,C., Fang,R., Guegler,K. et al., (2004) Nat. Biotechnol., 22, 707-716]. Here, we confirm this observation, and we show that ZFP206 expression decreases rapidly upon differentiation of cultured mouse ES cells, and during development of mouse embryos. We find that there are at least six isoforms of the ZFP206 transcript, the longest being predominant. Overexpression and depletion experiments show that Zfp206 promotes formation of undifferentiated ES cell clones, and positively regulates abundance of a very small set of transcripts whose expression is also specific to ES cells and the two- to four-cell stages of preimplantation embryos. This set includes members of the Zscan4, Thoc4, Tcstv1 and eIF-1A gene families, none of which have been functionally characterized in vivo but whose members include apparent transcription factors, RNA-binding proteins and translation factors. Together, these data indicate that Zfp206 is a regulator of ES cell differentiation that controls a set of genes expressed very early in development, most of which themselves appear to be regulators.

  9. Glucose metabolism regulates T cell activation, differentiation and functions

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    Clovis Steve Palmer

    2015-01-01

    Full Text Available The adaptive immune system is equipped to eliminate both tumors and pathogenic microorganisms. It requires a series of complex and coordinated signals to drive the activation, proliferation and differentiation of appropriate T cell subsets. It is now established that changes in cellular activation are coupled to profound changes in cellular metabolism. In addition, emerging evidence now suggest that specific metabolic alterations associated with distinct T cell subsets may be ancillary to their differentiation and influential in their immune functions. The Warburg effect originally used to describe a phenomenon in which most cancer cells relied on aerobic glycolysis for their growth is a key process that sustain T cell activation and differentiation. Here we review how different aspects of metabolism in T cells influence their functions, focusing on the emerging role of key regulators of glucose metabolism such as HIF-1α. A thorough understanding of the role of metabolism in T cell function could provide insights into mechanisms involved in inflammatory-mediated conditions, with the potential for developing novel therapeutic approaches to treat these diseases.

  10. Mirna biogenesis pathway is differentially regulated during adipose derived stromal/stem cell differentiation.

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    Martin, E C; Qureshi, A T; Llamas, C B; Burow, M E; King, A G; Lee, O C; Dasa, V; Freitas, M A; Forsberg, J A; Elster, E A; Davis, T A; Gimble, J M

    2018-02-07

    Stromal/stem cell differentiation is controlled by a vast array of regulatory mechanisms. Included within these are methods of mRNA gene regulation that occur at the level of epigenetic, transcriptional, and/or posttranscriptional modifications. Current studies that evaluate the posttranscriptional regulation of mRNA demonstrate microRNAs (miRNAs) as key mediators of stem cell differentiation through the inhibition of mRNA translation. miRNA expression is enhanced during both adipogenic and osteogenic differentiation; however, the mechanism by which miRNA expression is altered during stem cell differentiation is less understood. Here we demonstrate for the first time that adipose-derived stromal/stem cells (ASCs) induced to an adipogenic or osteogenic lineage have differences in strand preference (-3p and -5p) for miRNAs originating from the same primary transcript. Furthermore, evaluation of miRNA expression in ASCs demonstrates alterations in both miRNA strand preference and 5'seed site heterogeneity. Additionally, we show that during stem cell differentiation there are alterations in expression of genes associated with the miRNA biogenesis pathway. Quantitative RT-PCR demonstrated changes in the Argonautes (AGO1-4), Drosha, and Dicer at intervals of ASC adipogenic and osteogenic differentiation compared to untreated ASCs. Specifically, we demonstrated altered expression of the AGOs occurring during both adipogenesis and osteogenesis, with osteogenesis increasing AGO1-4 expression and adipogenesis decreasing AGO1 gene and protein expression. These data demonstrate changes to components of the miRNA biogenesis pathway during stromal/stem cell differentiation. Identifying regulatory mechanisms for miRNA processing during ASC differentiation may lead to novel mechanisms for the manipulation of lineage differentiation of the ASC through the global regulation of miRNA as opposed to singular regulatory mechanisms.

  11. Prion protein expression regulates embryonic stem cell pluripotency and differentiation.

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    Alberto Miranda

    2011-04-01

    Full Text Available Cellular prion protein (PRNP is a glycoprotein involved in the pathogenesis of transmissible spongiform encephalopathies (TSEs. Although the physiological function of PRNP is largely unknown, its key role in prion infection has been extensively documented. This study examines the functionality of PRNP during the course of embryoid body (EB differentiation in mouse Prnp-null (KO and WT embryonic stem cell (ESC lines. The first feature observed was a new population of EBs that only appeared in the KO line after 5 days of differentiation. These EBs were characterized by their expression of several primordial germ cell (PGC markers until Day 13. In a comparative mRNA expression analysis of genes playing an important developmental role during ESC differentiation to EBs, Prnp was found to participate in the transcription of a key pluripotency marker such as Nanog. A clear switching off of this gene on Day 5 was observed in the KO line as opposed to the WT line, in which maximum Prnp and Nanog mRNA levels appeared at this time. Using a specific antibody against PRNP to block PRNP pathways, reduced Nanog expression was confirmed in the WT line. In addition, antibody-mediated inhibition of ITGB5 (integrin αvβ5 in the KO line rescued the low expression of Nanog on Day 5, suggesting the regulation of Nanog transcription by Prnp via this Itgb5. mRNA expression analysis of the PRNP-related proteins PRND (Doppel and SPRN (Shadoo, whose PRNP function is known to be redundant, revealed their incapacity to compensate for the absence of PRNP during early ESC differentiation. Our findings provide strong evidence for a relationship between Prnp and several key pluripotency genes and attribute Prnp a crucial role in regulating self-renewal/differentiation status of ESC, confirming the participation of PRNP during early embryogenesis.

  12. Regulation of TFIIIB during F9 cell differentiation.

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    Athineos, Dimitris; Marshall, Lynne; White, Robert J

    2010-03-12

    Differentiation of F9 embryonal carcinoma (EC) cells into parietal endoderm (PE) provides a tractable model system for studying molecular events during early and inaccessible stages of murine development. PE formation is accompanied by extensive changes in gene expression both in vivo and in culture. One of the most dramatic is the ~10-fold decrease in transcriptional output by RNA polymerase (pol) III. This has been attributed to changes in activity of TFIIIB, a factor that is necessary and sufficient to recruit pol III to promoters. The goal of this study was to identify molecular changes that can account for the low activity of TFIIIB following F9 cell differentiation. Three essential subunits of TFIIIB decrease in abundance as F9 cells differentiate; these are Brf1 and Bdp1, which are pol III-specific, and TBP, which is also used by pols I and II. The decreased levels of Brf1 and Bdp1 proteins can be explained by reduced expression of the corresponding mRNAs. However, this is not the case for TBP, which is regulated post-transcriptionally. In proliferating cells, pol III transcription is stimulated by the proto-oncogene product c-Myc and the mitogen-activated protein kinase Erk, both of which bind to TFIIIB. However, c-Myc levels fall during differentiation and Erk becomes inactive through dephosphorylation. The diminished abundance of TFIIIB is therefore likely to be compounded by changes to these positive regulators that are required for its full activity. In addition, PE cells have elevated levels of the retinoblastoma protein RB, which is known to bind and repress TFIIIB. The low activity of TFIIIB in PE can be attributed to a combination of changes, any one of which could be sufficient to inhibit pol III transcription. Declining levels of essential TFIIIB subunits and of activators that are required for maximal TFIIIB activity are accompanied by an increase in a potent repressor of TFIIIB. These events provide fail-safe guarantees to ensure that pol III

  13. Enteric neural crest cells regulate vertebrate stomach patterning and differentiation.

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    Faure, Sandrine; McKey, Jennifer; Sagnol, Sébastien; de Santa Barbara, Pascal

    2015-01-15

    In vertebrates, the digestive tract develops from a uniform structure where reciprocal epithelial-mesenchymal interactions pattern this complex organ into regions with specific morphologies and functions. Concomitant with these early patterning events, the primitive GI tract is colonized by the vagal enteric neural crest cells (vENCCs), a population of cells that will give rise to the enteric nervous system (ENS), the intrinsic innervation of the GI tract. The influence of vENCCs on early patterning and differentiation of the GI tract has never been evaluated. In this study, we report that a crucial number of vENCCs is required for proper chick stomach development, patterning and differentiation. We show that reducing the number of vENCCs by performing vENCC ablations induces sustained activation of the BMP and Notch pathways in the stomach mesenchyme and impairs smooth muscle development. A reduction in vENCCs also leads to the transdifferentiation of the stomach into a stomach-intestinal mixed phenotype. In addition, sustained Notch signaling activity in the stomach mesenchyme phenocopies the defects observed in vENCC-ablated stomachs, indicating that inhibition of the Notch signaling pathway is essential for stomach patterning and differentiation. Finally, we report that a crucial number of vENCCs is also required for maintenance of stomach identity and differentiation through inhibition of the Notch signaling pathway. Altogether, our data reveal that, through the regulation of mesenchyme identity, vENCCs act as a new mediator in the mesenchymal-epithelial interactions that control stomach development. © 2015. Published by The Company of Biologists Ltd.

  14. Expression profiling of genes regulated by TGF-beta: Differential regulation in normal and tumour cells

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    Takahashi Takashi

    2007-04-01

    Full Text Available Abstract Background TGF-beta is one of the key cytokines implicated in various disease processes including cancer. TGF-beta inhibits growth and promotes apoptosis in normal epithelial cells and in contrast, acts as a pro-tumour cytokine by promoting tumour angiogenesis, immune-escape and metastasis. It is not clear if various actions of TGF-beta on normal and tumour cells are due to differential gene regulations. Hence we studied the regulation of gene expression by TGF-beta in normal and cancer cells. Results Using human 19 K cDNA microarrays, we show that 1757 genes are exclusively regulated by TGF-beta in A549 cells in contrast to 733 genes exclusively regulated in HPL1D cells. In addition, 267 genes are commonly regulated in both the cell-lines. Semi-quantitative and real-time qRT-PCR analysis of some genes agrees with the microarray data. In order to identify the signalling pathways that influence TGF-beta mediated gene regulation, we used specific inhibitors of p38 MAP kinase, ERK kinase, JNK kinase and integrin signalling pathways. The data suggest that regulation of majority of the selected genes is dependent on at least one of these pathways and this dependence is cell-type specific. Interestingly, an integrin pathway inhibitor, RGD peptide, significantly affected TGF-beta regulation of Thrombospondin 1 in A549 cells. Conclusion These data suggest major differences with respect to TGF-beta mediated gene regulation in normal and transformed cells and significant role of non-canonical TGF-beta pathways in the regulation of many genes by TGF-beta.

  15. Regulation of Stem Cell Differentiation by Histone Methyltransferases and Demethylases

    DEFF Research Database (Denmark)

    Pasini, D; Bracken, A P; Agger, K

    2008-01-01

    The generation of different cell types from stem cells containing identical genetic information and their organization into tissues and organs during development is a highly complex process that requires defined transcriptional programs. Maintenance of such programs is epigenetically regulated...... and the factors involved in these processes are often essential for development. The activities required for cell-fate decisions are frequently deregulated in human tumors, and the elucidation of the molecular mechanisms that regulate these processes is therefore important for understanding both developmental...

  16. Streptomyces sporulation - Genes and regulators involved in bacterial cell differentiation

    OpenAIRE

    Larsson, Jessica

    2010-01-01

    Streptomycetes are Gram-positive bacteria with a complex developmental life cycle. They form spores on specialized cells called aerial hyphae, and this sporulation involves alterations in growth, morphogenesis and cell cycle processes like cell division and chromosome segregation. Understanding the developmental mechanisms that streptomycetes have evolved for regulating for example cell division is of general interest in bacterial cell biology. It can also be valuable in the design of new dru...

  17. BMP signalling differentially regulates distinct haematopoietic stem cell types

    NARCIS (Netherlands)

    M. Crisan (Mihaela); P. Solaimani Kartalaei (Parham); C.S. Vink (Chris); T. Yamada-Inagawa (Tomoko); K. Bollerot (Karine); W.F.J. van IJcken (Wilfred); R. Van Der Linden (Reinier); S.C. de Sousa Lopes (Susana Chuva); R. Monteiro (Rui); C.L. Mummery (Christine); E.A. Dzierzak (Elaine)

    2015-01-01

    textabstractAdult haematopoiesis is the outcome of distinct haematopoietic stem cell (HSC) subtypes with self-renewable repopulating ability, but with different haematopoietic cell lineage outputs. The molecular basis for this heterogeneity is largely unknown. BMP signalling regulates HSCs as they

  18. Neuron-NG2 Cell Synapses: Novel Functions for Regulating NG2 Cell Proliferation and Differentiation

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    Qian-Kun Yang

    2013-01-01

    Full Text Available NG2 cells are a population of CNS cells that are distinct from neurons, mature oligodendrocytes, astrocytes, and microglia. These cells can be identified by their NG2 proteoglycan expression. NG2 cells have a highly branched morphology, with abundant processes radiating from the cell body, and express a complex set of voltage-gated channels, AMPA/kainate, and GABA receptors. Neurons notably form classical and nonclassical synapses with NG2 cells, which have varied characteristics and functions. Neuron-NG2 cell synapses could fine-tune NG2 cell activities, including the NG2 cell cycle, differentiation, migration, and myelination, and may be a novel potential therapeutic target for NG2 cell-related diseases, such as hypoxia-ischemia injury and periventricular leukomalacia. Furthermore, neuron-NG2 cell synapses may be correlated with the plasticity of CNS in adulthood with the synaptic contacts passing onto their progenies during proliferation, and synaptic contacts decrease rapidly upon NG2 cell differentiation. In this review, we highlight the characteristics of classical and nonclassical neuron-NG2 cell synapses, the potential functions, and the fate of synaptic contacts during proliferation and differentiation, with the emphasis on the regulation of the NG2 cell cycle by neuron-NG2 cell synapses and their potential underlying mechanisms.

  19. APLP2 regulates neuronal stem cell differentiation during cortical development.

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    Shariati, S Ali M; Lau, Pierre; Hassan, Bassem A; Müller, Ulrike; Dotti, Carlos G; De Strooper, Bart; Gärtner, Annette

    2013-03-01

    Expression of amyloid precursor protein (APP) and its two paralogues, APLP1 and APLP2 during brain development coincides with key cellular events such as neuronal differentiation and migration. However, genetic knockout and shRNA studies have led to contradictory conclusions about their role during embryonic brain development. To address this issue, we analysed in depth the role of APLP2 during neurogenesis by silencing APLP2 in vivo in an APP/APLP1 double knockout mouse background. We find that under these conditions cortical progenitors remain in their undifferentiated state much longer, displaying a higher number of mitotic cells. In addition, we show that neuron-specific APLP2 downregulation does not impact the speed or position of migrating excitatory cortical neurons. In summary, our data reveal that APLP2 is specifically required for proper cell cycle exit of neuronal progenitors, and thus has a distinct role in priming cortical progenitors for neuronal differentiation.

  20. Decoding cell signalling and regulation of oligodendrocyte differentiation.

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    Santos, A K; Vieira, M S; Vasconcellos, R; Goulart, V A M; Kihara, A H; Resende, R R

    2018-05-22

    Oligodendrocytes are fundamental for the functioning of the nervous system; they participate in several cellular processes, including axonal myelination and metabolic maintenance for astrocytes and neurons. In the mammalian nervous system, they are produced through waves of proliferation and differentiation, which occur during embryogenesis. However, oligodendrocytes and their precursors continue to be generated during adulthood from specific niches of stem cells that were not recruited during development. Deficiencies in the formation and maturation of these cells can generate pathologies mainly related to myelination. Understanding the mechanisms involved in oligodendrocyte development, from the precursor to mature cell level, will allow inferring therapies and treatments for associated pathologies and disorders. Such mechanisms include cell signalling pathways that involve many growth factors, small metabolic molecules, non-coding RNAs, and transcription factors, as well as specific elements of the extracellular matrix, which act in a coordinated temporal and spatial manner according to a given stimulus. Deciphering those aspects will allow researchers to replicate them in vitro in a controlled environment and thus mimic oligodendrocyte maturation to understand the role of oligodendrocytes in myelination in pathologies and normal conditions. In this study, we review these aspects, based on the most recent in vivo and in vitro data on oligodendrocyte generation and differentiation. Copyright © 2018 Elsevier Ltd. All rights reserved.

  1. New insights into redox regulation of stem cell self-renewal and differentiation.

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    Ren, Fenglian; Wang, Kui; Zhang, Tao; Jiang, Jingwen; Nice, Edouard Collins; Huang, Canhua

    2015-08-01

    Reactive oxygen species (ROS), the natural byproducts of aerobic metabolism, are precisely orchestrated to evoke diverse signaling pathways. To date, studies have focused mainly on the detrimental effects of ROS in stem cells. Recently, accumulating evidence has suggested that ROS also function as second messengers that modulate stem cell self-renewal and differentiation by regulating intricate signaling networks. Although many efforts have been made to clarify the general effects of ROS on signal transduction in stem cells, less is known about the initial and direct executors of ROS signaling, which are known as 'redox sensors'. Modifications of cysteine residues in redox sensors are of significant importance in the modulation of protein function in response to different redox conditions. Intriguingly, most key molecules in ROS signaling and cell cycle regulation (including transcriptional factors and kinases) that are crucial in the regulation of stem cell self-renewal and differentiation have the potential to be redox sensors. We highlight herein the importance of redox regulation of these key regulators in stem cell self-renewal and differentiation. Understanding the mechanisms of redox regulation in stem cell self-renewal and differentiation will open exciting new perspectives for stem cell biology. This article is part of a Special Issue entitled Redox regulation of differentiation and de-differentiation. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. Mitochondrial activity in the regulation of stem cell self-renewal and differentiation.

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    Khacho, Mireille; Slack, Ruth S

    2017-12-01

    Mitochondria are classically known as the essential energy producers in cells. As such, the activation of mitochondrial metabolism upon cellular differentiation was deemed a necessity to fuel the high metabolic needs of differentiated cells. However, recent studies have revealed a direct role for mitochondrial activity in the regulation of stem cell fate and differentiation. Several components of mitochondrial metabolism and respiration have now been shown to regulate different aspects of stem cell differentiation through signaling, transcriptional, proteomic and epigenetic modulations. In light of these findings mitochondrial metabolism is no longer considered a consequence of cellular differentiation, but rather a key regulatory mechanism of this process. This review will focus on recent progress that defines mitochondria as the epicenters for the regulation of stem cell fate decisions. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Human Long Noncoding RNA Regulation of Stem Cell Potency and Differentiation

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    Seahyoung Lee

    2017-01-01

    Full Text Available Because of their capability of differentiation into lineage-specific cells, stem cells are an attractive therapeutic modality in regenerative medicine. To develop an effective stem cell-based therapeutic strategy with predictable results, deeper understanding of the underlying molecular mechanisms of stem cell differentiation and/or pluripotency maintenance is required. Thus, reviewing the key factors involved in the transcriptional and epigenetic regulation of stem cell differentiation and maintenance is important. Accumulating data indicate that long noncoding RNAs (lncRNAs mediate numerous biological processes, including stem cell differentiation and maintenance. Here, we review recent findings on the human lncRNA regulation of stem cell potency and differentiation. Although the clinical implication of these lncRNAs is only beginning to be elucidated, it is anticipated that lncRNAs will become important therapeutic targets in the near future.

  4. Analysis of mammary specific gene locus regulation in differentiated cells derived by somatic cell fusion

    International Nuclear Information System (INIS)

    Robinson, Claire; Kolb, Andreas F.

    2009-01-01

    The transcriptional regulation of a gene is best analysed in the context of its normal chromatin surroundings. However, most somatic cells, in contrast to embryonic stem cells, are refractory to accurate modification by homologous recombination. We show here that it is possible to introduce precise genomic modifications in ES cells and to analyse the phenotypic consequences in differentiated cells by using a combination of gene targeting, site-specific recombination and somatic cell fusion. To provide a proof of principle, we have analysed the regulation of the casein gene locus in mammary gland cells derived from modified murine ES cells by somatic cell fusion. A β-galactosidase reporter gene was inserted in place of the β-casein gene and the modified ES cells, which do not express the reporter gene, were fused with the mouse mammary gland cell line HC11. The resulting cell clones expressed the β-galactosidase gene to a similar extent and with similar hormone responsiveness as the endogenous gene. However, a reporter gene under the control of a minimal β-casein promoter (encompassing the two consensus STAT5 binding sites which mediate the hormone response of the casein genes) was unable to replicate expression levels or hormone responsiveness of the endogenous gene when inserted into the same site of the casein locus. As expected, these results implicate sequences other than the STAT5 sites in the regulation of the β-casein gene

  5. Perturbation-expression analysis identifies RUNX1 as a regulator of human mammary stem cell differentiation.

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    Ethan S Sokol

    2015-04-01

    Full Text Available The search for genes that regulate stem cell self-renewal and differentiation has been hindered by a paucity of markers that uniquely label stem cells and early progenitors. To circumvent this difficulty we have developed a method that identifies cell-state regulators without requiring any markers of differentiation, termed Perturbation-Expression Analysis of Cell States (PEACS. We have applied this marker-free approach to screen for transcription factors that regulate mammary stem cell differentiation in a 3D model of tissue morphogenesis and identified RUNX1 as a stem cell regulator. Inhibition of RUNX1 expanded bipotent stem cells and blocked their differentiation into ductal and lobular tissue rudiments. Reactivation of RUNX1 allowed exit from the bipotent state and subsequent differentiation and mammary morphogenesis. Collectively, our findings show that RUNX1 is required for mammary stem cells to exit a bipotent state, and provide a new method for discovering cell-state regulators when markers are not available.

  6. Cell recognition molecule L1 promotes embryonic stem cell differentiation through the regulation of cell surface glycosylation

    Energy Technology Data Exchange (ETDEWEB)

    Li, Ying [Department of Biochemistry and Molecular Biology, Dalian Medical University, Dalian 116044 (China); Department of Clinical Laboratory, Second Affiliated Hospital of Dalian Medical University, Dalian 116023 (China); Huang, Xiaohua [Department of Biochemistry and Molecular Biology, Dalian Medical University, Dalian 116044 (China); Department of Clinical Biochemistry, College of Laboratory Medicine, Dalian Medical University, Dalian 116044 (China); An, Yue [Department of Clinical Laboratory, Second Affiliated Hospital of Dalian Medical University, Dalian 116023 (China); Ren, Feng [Department of Biochemistry and Molecular Biology, Dalian Medical University, Dalian 116044 (China); Yang, Zara Zhuyun; Zhu, Hongmei; Zhou, Lei [The Key Laboratory of Stem Cell and Regenerative Medicine, Institute of Molecular and Clinical Medicine, Kunming Medical University, Kunming 650228 (China); Department of Anatomy and Developmental Biology, Monash University, Clayton 3800 (Australia); He, Xiaowen; Schachner, Melitta [Keck Center for Collaborative Neuroscience and Department of Cell Biology and Neuroscience, Rutgers University, New Brunswick, NJ (United States); Xiao, Zhicheng, E-mail: zhicheng.xiao@monash.edu [The Key Laboratory of Stem Cell and Regenerative Medicine, Institute of Molecular and Clinical Medicine, Kunming Medical University, Kunming 650228 (China); Department of Anatomy and Developmental Biology, Monash University, Clayton 3800 (Australia); Ma, Keli, E-mail: makeli666@aliyun.com [Department of Biochemistry and Molecular Biology, Dalian Medical University, Dalian 116044 (China); Li, Yali, E-mail: yalilipaper@gmail.com [Department of Biochemistry and Molecular Biology, Dalian Medical University, Dalian 116044 (China); Department of Anatomy, National University of Singapore, Singapore 119078 (Singapore)

    2013-10-25

    Highlights: •Down-regulating FUT9 and ST3Gal4 expression blocks L1-induced neuronal differentiation of ESCs. •Up-regulating FUT9 and ST3Gal4 expression in L1-ESCs depends on the activation of PLCγ. •L1 promotes ESCs to differentiate into neuron through regulating cell surface glycosylation. -- Abstract: Cell recognition molecule L1 (CD171) plays an important role in neuronal survival, migration, differentiation, neurite outgrowth, myelination, synaptic plasticity and regeneration after injury. Our previous study has demonstrated that overexpressing L1 enhances cell survival and proliferation of mouse embryonic stem cells (ESCs) through promoting the expression of FUT9 and ST3Gal4, which upregulates cell surface sialylation and fucosylation. In the present study, we examined whether sialylation and fucosylation are involved in ESC differentiation through L1 signaling. RNA interference analysis showed that L1 enhanced differentiation of ESCs into neurons through the upregulation of FUT9 and ST3Gal4. Furthermore, blocking the phospholipase Cγ (PLCγ) signaling pathway with either a specific PLCγ inhibitor or knockdown PLCγ reduced the expression levels of both FUT9 and ST3Gal4 mRNAs and inhibited L1-mediated neuronal differentiation. These results demonstrate that L1 promotes neuronal differentiation from ESCs through the L1-mediated enhancement of FUT9 and ST3Gal4 expression.

  7. Cell recognition molecule L1 promotes embryonic stem cell differentiation through the regulation of cell surface glycosylation

    International Nuclear Information System (INIS)

    Li, Ying; Huang, Xiaohua; An, Yue; Ren, Feng; Yang, Zara Zhuyun; Zhu, Hongmei; Zhou, Lei; He, Xiaowen; Schachner, Melitta; Xiao, Zhicheng; Ma, Keli; Li, Yali

    2013-01-01

    Highlights: •Down-regulating FUT9 and ST3Gal4 expression blocks L1-induced neuronal differentiation of ESCs. •Up-regulating FUT9 and ST3Gal4 expression in L1-ESCs depends on the activation of PLCγ. •L1 promotes ESCs to differentiate into neuron through regulating cell surface glycosylation. -- Abstract: Cell recognition molecule L1 (CD171) plays an important role in neuronal survival, migration, differentiation, neurite outgrowth, myelination, synaptic plasticity and regeneration after injury. Our previous study has demonstrated that overexpressing L1 enhances cell survival and proliferation of mouse embryonic stem cells (ESCs) through promoting the expression of FUT9 and ST3Gal4, which upregulates cell surface sialylation and fucosylation. In the present study, we examined whether sialylation and fucosylation are involved in ESC differentiation through L1 signaling. RNA interference analysis showed that L1 enhanced differentiation of ESCs into neurons through the upregulation of FUT9 and ST3Gal4. Furthermore, blocking the phospholipase Cγ (PLCγ) signaling pathway with either a specific PLCγ inhibitor or knockdown PLCγ reduced the expression levels of both FUT9 and ST3Gal4 mRNAs and inhibited L1-mediated neuronal differentiation. These results demonstrate that L1 promotes neuronal differentiation from ESCs through the L1-mediated enhancement of FUT9 and ST3Gal4 expression

  8. Plant GSK3 proteins regulate xylem cell differentiation downstream of TDIF-TDR signalling

    Science.gov (United States)

    Kondo, Yuki; Ito, Tasuku; Nakagami, Hirofumi; Hirakawa, Yuki; Saito, Masato; Tamaki, Takayuki; Shirasu, Ken; Fukuda, Hiroo

    2014-03-01

    During plant radial growth typically seen in trees, procambial and cambial cells act as meristematic cells in the vascular system to self-proliferate and differentiate into xylem cells. These two processes are regulated by a signalling pathway composed of a peptide ligand and its receptor; tracheary element differentiation inhibitory factor (TDIF) and TDIF RECEPTOR (TDR). Here we show that glycogen synthase kinase 3 proteins (GSK3s) are crucial downstream components of the TDIF signalling pathway suppressing xylem differentiation from procambial cells. TDR interacts with GSK3s at the plasma membrane and activates GSK3s in a TDIF-dependent fashion. Consistently, a specific inhibitor of plant GSK3s strongly induces xylem cell differentiation through BRI1-EMS SUPPRESSOR 1 (BES1), a well-known target transcription factor of GSK3s. Our findings provide insight into the regulation of cell fate determination in meristem maintenance.

  9. MicroRNA-138 regulates osteogenic differentiation of human stromal (mesenchymal) stem cells in vivo

    DEFF Research Database (Denmark)

    Eskildsen, Tilde; Taipaleenmäki, Hanna; Stenvang, Jan

    2011-01-01

    Elucidating the molecular mechanisms that regulate human stromal (mesenchymal) stem cell (hMSC) differentiation into osteogenic lineage is important for the development of anabolic therapies for treatment of osteoporosis. MicroRNAs (miRNAs) are short, noncoding RNAs that act as key regulators......-regulated during osteoblast differentiation of hMSCs. Overexpression of miR-138 inhibited osteoblast differentiation of hMSCs in vitro, whereas inhibition of miR-138 function by antimiR-138 promoted expression of osteoblast-specific genes, alkaline phosphatase (ALP) activity, and matrix mineralization. Furthermore...

  10. Suppression of MicroRNA let-7a Expression by Agmatine Regulates Neural Stem Cell Differentiation.

    Science.gov (United States)

    Song, Juhyun; Oh, Yumi; Kim, Jong Youl; Cho, Kyoung Joo; Lee, Jong Eun

    2016-11-01

    Neural stem cells (NSCs) effectively reverse some severe central nervous system (CNS) disorders, due to their ability to differentiate into neurons. Agmatine, a biogenic amine, has cellular protective effects and contributes to cellular proliferation and differentiation in the CNS. Recent studies have elucidated the function of microRNA let-7a (let-7a) as a regulator of cell differentiation with roles in regulating genes associated with CNS neurogenesis. This study aimed to investigate whether agmatine modulates the expression of crucial regulators of NSC differentiation including DCX, TLX, c-Myc, and ERK by controlling let-7a expression. Our data suggest that high levels of let-7a promoted the expression of TLX and c-Myc, as well as repressed DCX and ERK expression. In addition, agmatine attenuated expression of TLX and increased expression of ERK by negatively regulating let-7a. Our study therefore enhances the present understanding of the therapeutic potential of NSCs in CNS disorders.

  11. VMAT2 identified as a regulator of late-stage β-cell differentiation.

    Science.gov (United States)

    Sakano, Daisuke; Shiraki, Nobuaki; Kikawa, Kazuhide; Yamazoe, Taiji; Kataoka, Masateru; Umeda, Kahoko; Araki, Kimi; Mao, Di; Matsumoto, Shirou; Nakagata, Naomi; Andersson, Olov; Stainier, Didier; Endo, Fumio; Kume, Kazuhiko; Uesugi, Motonari; Kume, Shoen

    2014-02-01

    Cell replacement therapy for diabetes mellitus requires cost-effective generation of high-quality, insulin-producing, pancreatic β cells from pluripotent stem cells. Development of this technique has been hampered by a lack of knowledge of the molecular mechanisms underlying β-cell differentiation. The present study identified reserpine and tetrabenazine (TBZ), both vesicular monoamine transporter 2 (VMAT2) inhibitors, as promoters of late-stage differentiation of Pdx1-positive pancreatic progenitor cells into Neurog3 (referred to henceforth as Ngn3)-positive endocrine precursors. VMAT2-controlled monoamines, such as dopamine, histamine and serotonin, negatively regulated β-cell differentiation. Reserpine or TBZ acted additively with dibutyryl adenosine 3',5'-cyclic AMP, a cell-permeable cAMP analog, to potentiate differentiation of embryonic stem (ES) cells into β cells that exhibited glucose-stimulated insulin secretion. When ES cell-derived β cells were transplanted into AKITA diabetic mice, the cells reversed hyperglycemia. Our protocol provides a basis for the understanding of β-cell differentiation and its application to a cost-effective production of functional β cells for cell therapy.

  12. SAM pointed domain ETS factor (SPDEF) regulates terminal differentiation and maturation of intestinal goblet cells

    Energy Technology Data Exchange (ETDEWEB)

    Noah, Taeko K.; Kazanjian, Avedis [Gastroenterology, Hepatology and Nutrition, Cincinnati Children' s Hospital Medical Center and University of Cincinnati College of Medicine, Cincinnati, OH (United States); Whitsett, Jeffrey [Developmental Biology, Cincinnati Children' s Hospital Medical Center and University of Cincinnati College of Medicine, Cincinnati, OH (United States); Neonatology and Pulmonary Biology, Cincinnati Children' s Hospital Medical Center and University of Cincinnati College of Medicine, Cincinnati, OH (United States); Shroyer, Noah F., E-mail: noah.shroyer@cchmc.org [Gastroenterology, Hepatology and Nutrition, Cincinnati Children' s Hospital Medical Center and University of Cincinnati College of Medicine, Cincinnati, OH (United States); Developmental Biology, Cincinnati Children' s Hospital Medical Center and University of Cincinnati College of Medicine, Cincinnati, OH (United States)

    2010-02-01

    Background and Aims: SPDEF (also termed PDEF or PSE) is an ETS family transcription factor that regulates gene expression in the prostate and goblet cell hyperplasia in the lung. Spdef has been reported to be expressed in the intestine. In this paper, we identify an important role for Spdef in regulating intestinal epithelial cell homeostasis and differentiation. Methods: SPDEF expression was inhibited in colon cancer cells to determine its ability to control goblet cell gene activation. The effects of transgenic expression of Spdef on intestinal differentiation and homeostasis were determined. Results: In LS174T colon cancer cells treated with Notch/{gamma}-secretase inhibitor to activate goblet cell gene expression, shRNAs that inhibited SPDEF also repressed expression of goblet cell genes AGR2, MUC2, RETLNB, and SPINK4. Transgenic expression of Spdef caused the expansion of intestinal goblet cells and corresponding reduction in Paneth, enteroendocrine, and absorptive enterocytes. Spdef inhibited proliferation of intestinal crypt cells without induction of apoptosis. Prolonged expression of the Spdef transgene caused a progressive reduction in the number of crypts that expressed Spdef, consistent with its inhibitory effects on cell proliferation. Conclusions: Spdef was sufficient to inhibit proliferation of intestinal progenitors and induce differentiation into goblet cells; SPDEF was required for activation of goblet cell associated genes in vitro. These data support a model in which Spdef promotes terminal differentiation into goblet cells of a common goblet/Paneth progenitor.

  13. The regulation and role of c-FLIP in human Th cell differentiation.

    Science.gov (United States)

    Kyläniemi, Minna K; Kaukonen, Riina; Myllyviita, Johanna; Rasool, Omid; Lahesmaa, Riitta

    2014-01-01

    The early differentiation of T helper (Th) cells is a tightly controlled and finely balanced process, which involves several factors including cytokines, transcription factors and co-stimulatory molecules. Recent studies have shown that in addition to the regulation of apoptosis, caspase activity is also needed for Th cell proliferation and activation and it might play a role in Th cell differentiation. The isoforms of the cellular FLICE inhibitory protein (c-FLIP) are regulators of CASPASE-8 activity and the short isoform, c-FLIPS, has been shown to be up-regulated by IL-4, the Th2 driving cytokine. In this work, we have studied the expression and functional role of three c-FLIP isoforms during the early Th cell differentiation. Only two of the isoforms, c-FLIPS and c-FLIPL, were detected at the protein level although c-FLIPR was expressed at the mRNA level. The knockdown of c-FLIPL led to enhanced Th1 differentiation and elevated IL-4 production by Th2 cells, whereas the knockdown of c-FLIPS diminished GATA3 expression and IL-4 production by Th2 cells. In summary, our results provide new insight into the role of c-FLIP proteins in the early differentiation of human Th cells.

  14. TET2 Regulates Mast Cell Differentiation and Proliferation through Catalytic and Non-catalytic Activities

    Directory of Open Access Journals (Sweden)

    Sara Montagner

    2016-05-01

    Full Text Available Summary: Dioxygenases of the TET family impact genome functions by converting 5-methylcytosine (5mC in DNA to 5-hydroxymethylcytosine (5hmC. Here, we identified TET2 as a crucial regulator of mast cell differentiation and proliferation. In the absence of TET2, mast cells showed disrupted gene expression and altered genome-wide 5hmC deposition, especially at enhancers and in the proximity of downregulated genes. Impaired differentiation of Tet2-ablated cells could be relieved or further exacerbated by modulating the activity of other TET family members, and mechanistically it could be linked to the dysregulated expression of C/EBP family transcription factors. Conversely, the marked increase in proliferation induced by the loss of TET2 could be rescued exclusively by re-expression of wild-type or catalytically inactive TET2. Our data indicate that, in the absence of TET2, mast cell differentiation is under the control of compensatory mechanisms mediated by other TET family members, while proliferation is strictly dependent on TET2 expression. : The impact of TET enzymes on gene expression and cell function is incompletely understood. Montagner et al. investigate the TET-mediated regulation of mast cell differentiation and function, uncover transcriptional pathways regulated by TET2, and identify both enzymatic activity-dependent and -independent functions of TET2. Keywords: differentiation, DNA hydroxymethylation, epigenetics, mast cells, proliferation, TET

  15. Regulation, cell differentiation and protein-based inheritance.

    Science.gov (United States)

    Malagnac, Fabienne; Silar, Philippe

    2006-11-01

    Recent research using fungi as models provide new insight into the ability of regulatory networks to generate cellular states that are sufficiently stable to be faithfully transmitted to daughter cells, thereby generating epigenetic inheritance. Such protein-based inheritance is driven by infectious factors endowed with properties usually displayed by prions. We emphasize the contribution of regulatory networks to the emerging properties displayed by cells.

  16. Invariant NKT cells regulate experimental autoimmune uveitis through inhibition of Th17 differentiation.

    Science.gov (United States)

    Oh, Keunhee; Byoun, Ok-Jin; Ham, Don-Il; Kim, Yon Su; Lee, Dong-Sup

    2011-02-01

    Although NKT cells have been implicated in diverse immunomodulatory responses, the effector mechanisms underlying the NKT cell-mediated regulation of pathogenic T helper cells are not well understood. Here, we show that invariant NKT cells inhibited the differentiation of CD4(+) T cells into Th17 cells both in vitro and in vivo. The number of IL-17-producing CD4(+) T cells was reduced following co-culture with purified NK1.1(+) TCR(+) cells from WT, but not from CD1d(-/-) or Jα18(-/-) , mice. Co-cultured NKT cells from either cytokine-deficient (IL-4(-/-) , IL-10(-/-) , or IFN-γ(-/-) ) or WT mice efficiently inhibited Th17 differentiation. The contact-dependent mechanisms of NKT cell-mediated regulation of Th17 differentiation were confirmed using transwell co-culture experiments. On the contrary, the suppression of Th1 differentiation was dependent on IL-4 derived from the NKT cells. The in vivo regulatory capacity of NKT cells on Th17 cells was confirmed using an experimental autoimmune uveitis model induced with human IRBP(1-20) (IRBP, interphotoreceptor retinoid-binding protein) peptide. NKT cell-deficient mice (CD1d(-/-) or Jα18(-/-) ) demonstrated an increased disease severity, which was reversed by the transfer of WT or cytokine-deficient (IL-4(-/-) , IL-10(-/-) , or IFN-γ(-/-) ) NKT cells. Our results indicate that invariant NKT cells inhibited autoimmune uveitis predominantly through the cytokine-independent inhibition of Th17 differentiation. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Mechanical regulation of stem-cell differentiation by the stretch-activated Piezo channel.

    Science.gov (United States)

    He, Li; Si, Guangwei; Huang, Jiuhong; Samuel, Aravinthan D T; Perrimon, Norbert

    2018-03-01

    Somatic stem cells constantly adjust their self-renewal and lineage commitment by integrating various environmental cues to maintain tissue homeostasis. Although numerous chemical and biological signals have been identified that regulate stem-cell behaviour, whether stem cells can directly sense mechanical signals in vivo remains unclear. Here we show that mechanical stress regulates stem-cell differentiation in the adult Drosophila midgut through the stretch-activated ion channel Piezo. We find that Piezo is specifically expressed in previously unidentified enteroendocrine precursor cells, which have reduced proliferation ability and are destined to become enteroendocrine cells. Loss of Piezo activity reduces the generation of enteroendocrine cells in the adult midgut. In addition, ectopic expression of Piezo in all stem cells triggers both cell proliferation and enteroendocrine cell differentiation. Both the Piezo mutant and overexpression phenotypes can be rescued by manipulation of cytosolic Ca 2+ levels, and increases in cytosolic Ca 2+ resemble the Piezo overexpression phenotype, suggesting that Piezo functions through Ca 2+ signalling. Further studies suggest that Ca 2+ signalling promotes stem-cell proliferation and differentiation through separate pathways. Finally, Piezo is required for both mechanical activation of stem cells in a gut expansion assay and the increase of cytosolic Ca 2+ in response to direct mechanical stimulus in a gut compression assay. Thus, our study demonstrates the existence of a specific group of stem cells in the fly midgut that can directly sense mechanical signals through Piezo.

  18. Role of RHEB in Regulating Differentiation Fate of Mesenchymal Stem Cells for Cartilage and Bone Regeneration

    Directory of Open Access Journals (Sweden)

    Sajjad Ashraf

    2017-04-01

    Full Text Available Advances in mesenchymal stem cells (MSCs and cell replacement therapies are promising approaches to treat cartilage and bone defects since substantial differentiation capacities of MSCs match the demands of tissue regeneration. Our understanding of the dynamic process requiring indispensable differentiation of MSCs remains limited. Herein, we describe the role of RHEB (Ras homolog enriched in brain regulating gene signature for differentiation of human adipose derived mesenchymal stem cells (ASCs into chondrogenic, osteogenic, and adipogenic lineages. RHEB-overexpression increases the proliferation of the ASCs. RHEB enhances the chondrogenic differentiation of ASCs in 3D culture via upregulation of SOX9 with concomitant increase in glycosaminoglycans (GAGs, and type II collagen (COL2. RHEB increases the osteogenesis via upregulation of runt related transcription factor 2 (RUNX2 with an increase in the calcium and phosphate contents. RHEB also increases the expression of osteogenic markers, osteonectin and osteopontin. RHEB knockdown ASCs were incapable of expressing sufficient SRY (Sex determining region Y-box 9 (SOX9 and RUNX2, and therefore had decreased chondrogenic and osteogenic differentiation. RHEB-overexpression impaired ASCs differentiation into adipogenic lineage, through downregulation of CCAAT/enhancer binding protein beta (C/EBPβ. Conversely, RHEB knockdown abolished the negative regulation of adipogenesis. We demonstrate that RHEB is a novel regulator, with a critical role in ASCs lineage determination, and RHEB-modulated ASCs may be useful as a cell therapy for cartilage and bone defect treatments.

  19. Identifying microRNAs that Regulate Neuroblastoma Cell Differentiation

    Science.gov (United States)

    2015-10-01

    in Figure 3D -G, comparing to the control cells, more cells treated with miR-449a mimic or RA are negative for BrDU staining, which indicates that...predicted as miR-449a tar- gets decrease and increase in expression. The empiri- cal density curves in Fig- ure 3D further show the difference in the...Sang N, Druck T, Veron- ese ML, Allen SL, Chiorazzi N, Koff A, Heubner K, Croce CM, et al. Chromosomal mapping of members of the cdc2 family of

  20. Vitamin D receptor–retinoid X receptor heterodimer signaling regulates oligodendrocyte progenitor cell differentiation

    Science.gov (United States)

    de la Fuente, Alerie Guzman; Errea, Oihana; van Wijngaarden, Peter; Gonzalez, Ginez A.; Kerninon, Christophe; Jarjour, Andrew A.; Lewis, Hilary J.; Jones, Clare A.; Nait-Oumesmar, Brahim; Zhao, Chao; Huang, Jeffrey K.; ffrench-Constant, Charles

    2015-01-01

    The mechanisms regulating differentiation of oligodendrocyte (OLG) progenitor cells (OPCs) into mature OLGs are key to understanding myelination and remyelination. Signaling via the retinoid X receptor γ (RXR-γ) has been shown to be a positive regulator of OPC differentiation. However, the nuclear receptor (NR) binding partner of RXR-γ has not been established. In this study we show that RXR-γ binds to several NRs in OPCs and OLGs, one of which is vitamin D receptor (VDR). Using pharmacological and knockdown approaches we show that RXR–VDR signaling induces OPC differentiation and that VDR agonist vitamin D enhances OPC differentiation. We also show expression of VDR in OLG lineage cells in multiple sclerosis. Our data reveal a role for vitamin D in the regenerative component of demyelinating disease and identify a new target for remyelination medicines. PMID:26644513

  1. Biosynthesis of ribosomal RNA in nucleoli regulates pluripotency and differentiation ability of pluripotent stem cells.

    Science.gov (United States)

    Watanabe-Susaki, Kanako; Takada, Hitomi; Enomoto, Kei; Miwata, Kyoko; Ishimine, Hisako; Intoh, Atsushi; Ohtaka, Manami; Nakanishi, Mahito; Sugino, Hiromu; Asashima, Makoto; Kurisaki, Akira

    2014-12-01

    Pluripotent stem cells have been shown to have unique nuclear properties, for example, hyperdynamic chromatin and large, condensed nucleoli. However, the contribution of the latter unique nucleolar character to pluripotency has not been well understood. Here, we show that fibrillarin (FBL), a critical methyltransferase for ribosomal RNA (rRNA) processing in nucleoli, is one of the proteins highly expressed in pluripotent embryonic stem (ES) cells. Stable expression of FBL in ES cells prolonged the pluripotent state of mouse ES cells cultured in the absence of leukemia inhibitory factor (LIF). Analyses using deletion mutants and a point mutant revealed that the methyltransferase activity of FBL regulates stem cell pluripotency. Knockdown of this gene led to significant delays in rRNA processing, growth inhibition, and apoptosis in mouse ES cells. Interestingly, both partial knockdown of FBL and treatment with actinomycin D, an inhibitor of rRNA synthesis, induced the expression of differentiation markers in the presence of LIF and promoted stem cell differentiation into neuronal lineages. Moreover, we identified p53 signaling as the regulatory pathway for pluripotency and differentiation of ES cells. These results suggest that proper activity of rRNA production in nucleoli is a novel factor for the regulation of pluripotency and differentiation ability of ES cells. © 2014 AlphaMed Press.

  2. HDAC4 regulates satellite cell proliferation and differentiation by targeting P21 and Sharp1 genes.

    Science.gov (United States)

    Marroncelli, Nicoletta; Bianchi, Marzia; Bertin, Marco; Consalvi, Silvia; Saccone, Valentina; De Bardi, Marco; Puri, Pier Lorenzo; Palacios, Daniela; Adamo, Sergio; Moresi, Viviana

    2018-02-22

    Skeletal muscle exhibits a high regenerative capacity, mainly due to the ability of satellite cells to replicate and differentiate in response to appropriate stimuli. Epigenetic control is effective at different stages of this process. It has been shown that the chromatin-remodeling factor HDAC4 is able to regulate satellite cell proliferation and commitment. However, its molecular targets are still uncovered. To explain the signaling pathways regulated by HDAC4 in satellite cells, we generated tamoxifen-inducible mice with conditional inactivation of HDAC4 in Pax7 + cells (HDAC4 KO mice). We found that the proliferation and differentiation of HDAC4 KO satellite cells were compromised, although similar amounts of satellite cells were found in mice. Moreover, we found that the inhibition of HDAC4 in satellite cells was sufficient to block the differentiation process. By RNA-sequencing analysis we identified P21 and Sharp1 as HDAC4 target genes. Reducing the expression of these target genes in HDAC4 KO satellite cells, we also defined the molecular pathways regulated by HDAC4 in the epigenetic control of satellite cell expansion and fusion.

  3. Myostatin acts as an autocrine/paracrine negative regulator in myoblast differentiation from human induced pluripotent stem cells

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Fei; Kishida, Tsunao; Ejima, Akika [Department of Immunology, Kyoto Prefectural University of Medicine, Kyoto (Japan); Gojo, Satoshi [Department of Cardiac Support, Kyoto Prefectural University of Medicine, Kyoto (Japan); Mazda, Osam, E-mail: mazda@koto.kpu-m.ac.jp [Department of Immunology, Kyoto Prefectural University of Medicine, Kyoto (Japan)

    2013-02-08

    Highlights: ► iPS-derived cells express myostatin and its receptor upon myoblast differentiation. ► Myostatin inhibits myoblast differentiation by inhibiting MyoD and Myo5a induction. ► Silencing of myostatin promotes differentiation of human iPS cells into myoblasts. -- Abstract: Myostatin, also known as growth differentiation factor (GDF-8), regulates proliferation of muscle satellite cells, and suppresses differentiation of myoblasts into myotubes via down-regulation of key myogenic differentiation factors including MyoD. Recent advances in stem cell biology have enabled generation of myoblasts from pluripotent stem cells, but it remains to be clarified whether myostatin is also involved in regulation of artificial differentiation of myoblasts from pluripotent stem cells. Here we show that the human induced pluripotent stem (iPS) cell-derived cells that were induced to differentiate into myoblasts expressed myostatin and its receptor during the differentiation. An addition of recombinant human myostatin (rhMyostatin) suppressed induction of MyoD and Myo5a, resulting in significant suppression of myoblast differentiation. The rhMyostatin treatment also inhibited proliferation of the cells at a later phase of differentiation. RNAi-mediated silencing of myostatin promoted differentiation of human iPS-derived embryoid body (EB) cells into myoblasts. These results strongly suggest that myostatin plays an important role in regulation of myoblast differentiation from iPS cells of human origin. The present findings also have significant implications for potential regenerative medicine for muscular diseases.

  4. Myostatin acts as an autocrine/paracrine negative regulator in myoblast differentiation from human induced pluripotent stem cells

    International Nuclear Information System (INIS)

    Gao, Fei; Kishida, Tsunao; Ejima, Akika; Gojo, Satoshi; Mazda, Osam

    2013-01-01

    Highlights: ► iPS-derived cells express myostatin and its receptor upon myoblast differentiation. ► Myostatin inhibits myoblast differentiation by inhibiting MyoD and Myo5a induction. ► Silencing of myostatin promotes differentiation of human iPS cells into myoblasts. -- Abstract: Myostatin, also known as growth differentiation factor (GDF-8), regulates proliferation of muscle satellite cells, and suppresses differentiation of myoblasts into myotubes via down-regulation of key myogenic differentiation factors including MyoD. Recent advances in stem cell biology have enabled generation of myoblasts from pluripotent stem cells, but it remains to be clarified whether myostatin is also involved in regulation of artificial differentiation of myoblasts from pluripotent stem cells. Here we show that the human induced pluripotent stem (iPS) cell-derived cells that were induced to differentiate into myoblasts expressed myostatin and its receptor during the differentiation. An addition of recombinant human myostatin (rhMyostatin) suppressed induction of MyoD and Myo5a, resulting in significant suppression of myoblast differentiation. The rhMyostatin treatment also inhibited proliferation of the cells at a later phase of differentiation. RNAi-mediated silencing of myostatin promoted differentiation of human iPS-derived embryoid body (EB) cells into myoblasts. These results strongly suggest that myostatin plays an important role in regulation of myoblast differentiation from iPS cells of human origin. The present findings also have significant implications for potential regenerative medicine for muscular diseases

  5. [Comprehensive regulation effect of traditional Chinese medicine on proliferation and differentiation of neural stem cells].

    Science.gov (United States)

    Wang, Hong-Jin; Li, Jing-Jing; Ke, Hui; Xu, Xiao-Yu

    2017-11-01

    Since the discovery of neural stem cells(NSCs) in embryonic and adult mammalian central nervous systems, new approaches for proliferation and differentiation of NSCs have been put forward. One of the approaches to promote the clinical application of NSCs is to search effective methods to regulate the proliferation and differentiation. This problem is urgently to be solved in the medical field. Previous studies have shown that traditional Chinese medicine could promote the proliferation and differentiation of NSCs by regulating the relevant signaling pathway in vivo and in vitro. Domestic and foreign literatures for regulating the proliferation and differentiation of neural stem cells in recent 10 years and the reports for their target and signaling pathways were analyzed in this paper. Traditional Chinese medicine could regulate the proliferation and differentiation of NSCs through signaling pathways of Notch, PI3K/Akt, Wnt/β-catenin and GFs. However, studies about NSCs and traditional Chinese medicine should be further deepened; the mechanism of multiple targets and the comprehensive regulation function of traditional Chinese medicine should be clarified. Copyright© by the Chinese Pharmaceutical Association.

  6. Regulation of proliferation and differentiation of adipocyte precursor cells in rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Bouraoui, L; Gutiérrez, J; Navarro, I

    2008-09-01

    Here, we describe optimal conditions for the culture of rainbow trout (Oncorhynchus mykiss) pre-adipocytes obtained from adipose tissue and their differentiation into mature adipocytes, in order to study the endocrine control of adipogenesis. Pre-adipocytes were isolated by collagenase digestion and cultured on laminin or 1% gelatin substrate. The expression of proliferating cell nuclear antigen was used as a marker of cell proliferation on various days of culture. Insulin growth factor-I stimulated cell proliferation especially on days 5 and 7 of culture. Tumor necrosis factor alpha (TNFalpha) slightly enhanced cell proliferation only at a low dose. We verified the differentiation of cells grown in specific medium into mature adipocytes by oil red O (ORO) staining. Quantification of ORO showed an increase in triglycerides throughout culture. Immunofluorescence staining of cells at day 11 revealed the expression of CCAAT/enhancer-binding protein and peroxisome proliferator-activator receptor gamma, suggesting that these transcriptional factors are involved in adipocyte differentiation in trout. We also examined the effect of TNFalpha on the differentiation of these adipocytes in primary culture. TNFalpha inhibited the differentiation of these cells, as indicated by a decrease in glycerol-3-phosphate dehydrogenase activity, an established marker of adipocyte differentiation. In conclusion, the culture system described here for trout pre-adipocytes is a powerful tool to study the endocrine regulation of adipogenesis in this species.

  7. Non-coding RNAs as epigenetic regulator of glioma stem-like cell differentiation

    Directory of Open Access Journals (Sweden)

    Keisuke eKatsushima

    2014-02-01

    Full Text Available Glioblastomas show heterogeneous histological features. These distinct phenotypic states are thought to be associated with the presence of glioma stem cells (GSCs, which are highly tumorigenic and self-renewing sub-population of tumor cells that have different functional characteristics. Differentiation of GSCs may be regulated by multi-tiered epigenetic mechanisms that orchestrate the expression of thousands of genes. One such regulatory mechanism involves functional non-coding RNAs (ncRNAs, such as microRNAs (miRNAs; a large number of ncRNAs have been identified and shown to regulate the expression of genes associated with cell differentiation programs. Given the roles of miRNAs in cell differentiation, it is possible they are involved in the regulation of gene expression networks in GSCs that are important for the maintenance of the pluripotent state and for directing differentiation. Here, we review recent findings on ncRNAs associated with GSC differentiation and discuss how these ncRNAs contribute to the establishment of tissue heterogeneity during glioblastoma tumor formation.

  8. Regulation of normal B-cell differentiation and malignant B-cell survival by OCT2.

    Science.gov (United States)

    Hodson, Daniel J; Shaffer, Arthur L; Xiao, Wenming; Wright, George W; Schmitz, Roland; Phelan, James D; Yang, Yandan; Webster, Daniel E; Rui, Lixin; Kohlhammer, Holger; Nakagawa, Masao; Waldmann, Thomas A; Staudt, Louis M

    2016-04-05

    The requirement for the B-cell transcription factor OCT2 (octamer-binding protein 2, encoded by Pou2f2) in germinal center B cells has proved controversial. Here, we report that germinal center B cells are formed normally after depletion of OCT2 in a conditional knockout mouse, but their proliferation is reduced and in vivo differentiation to antibody-secreting plasma cells is blocked. This finding led us to examine the role of OCT2 in germinal center-derived lymphomas. shRNA knockdown showed that almost all diffuse large B-cell lymphoma (DLBCL) cell lines are addicted to the expression of OCT2 and its coactivator OCA-B. Genome-wide chromatin immunoprecipitation (ChIP) analysis and gene-expression profiling revealed the broad transcriptional program regulated by OCT2 that includes the expression of STAT3, IL-10, ELL2, XBP1, MYC, TERT, and ADA. Importantly, genetic alteration of OCT2 is not a requirement for cellular addiction in DLBCL. However, we detected amplifications of the POU2F2 locus in DLBCL tumor biopsies and a recurrent mutation of threonine 223 in the DNA-binding domain of OCT2. This neomorphic mutation subtly alters the DNA-binding preference of OCT2, leading to the transactivation of noncanonical target genes including HIF1a and FCRL3 Finally, by introducing mutations designed to disrupt the OCT2-OCA-B interface, we reveal a requirement for this protein-protein interface that ultimately might be exploited therapeutically. Our findings, combined with the predominantly B-cell-restricted expression of OCT2 and the absence of a systemic phenotype in our knockout mice, suggest that an OCT2-targeted therapeutic strategy would be efficacious in both major subtypes of DLBCL while avoiding systemic toxicity.

  9. miR-150-Mediated Foxo1 Regulation Programs CD8+ T Cell Differentiation.

    Science.gov (United States)

    Ban, Young Ho; Oh, Se-Chan; Seo, Sang-Hwan; Kim, Seok-Min; Choi, In-Pyo; Greenberg, Philip D; Chang, Jun; Kim, Tae-Don; Ha, Sang-Jun

    2017-09-12

    MicroRNA (miR)-150 is a developmental regulator of several immune-cell types, but its role in CD8 + T cells is largely unexplored. Here, we show that miR-150 regulates the generation of memory CD8 + T cells. After acute virus infection, miR-150 knockout (KO) mice exhibited an accelerated differentiation of CD8 + T cells into memory cells and improved production of effector cytokines. Additionally, miR-150 KO CD8 + T cells displayed an enhanced recall response and improved protection against infections with another virus and bacteria. We found that forkhead box O1 (Foxo1) and T cell-specific transcription factor 1 (TCF1) are upregulated during the early activation phase in miR-150 KO CD8 + T cells and that miR-150 directly targets and suppresses Foxo1. These results suggest that miR-150-mediated suppression of Foxo1 regulates the balance between effector and memory cell differentiation, which might aid in the development of improved vaccines and T cell therapeutics. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  10. Nutlin-3 down-regulates retinoblastoma protein expression and inhibits muscle cell differentiation

    Energy Technology Data Exchange (ETDEWEB)

    Walsh, Erica M. [Department of Biochemistry, Boston University School of Medicine, Boston, MA 02118 (United States); Niu, MengMeng; Bergholz, Johann [Center of Growth, Metabolism and Aging, College of Life Sciences, Sichuan University, Chengdu, 610014 China (China); Jim Xiao, Zhi-Xiong, E-mail: jxiao@bu.edu [Department of Biochemistry, Boston University School of Medicine, Boston, MA 02118 (United States); Center of Growth, Metabolism and Aging, College of Life Sciences, Sichuan University, Chengdu, 610014 China (China)

    2015-05-29

    The p53 tumor suppressor gene plays a critical role in regulation of proliferation, cell death and differentiation. The MDM2 oncoprotein is a major negative regulator for p53 by binding to and targeting p53 for proteasome-mediated degradation. The small molecule inhibitor, nutlin-3, disrupts MDM2-p53 interaction resulting in stabilization and activation of p53 protein. We have previously shown that nutlin-3 activates p53, leading to MDM2 accumulation as concomitant of reduced retinoblastoma (Rb) protein stability. It is well known that Rb is important in muscle development and myoblast differentiation and that rhabdomyosarcoma (RMS), or cancer of the skeletal muscle, typically harbors MDM2 amplification. In this study, we show that nutlin-3 inhibited myoblast proliferation and effectively prevented myoblast differentiation, as evidenced by lack of expression of muscle differentiation markers including myogenin and myosin heavy chain (MyHC), as well as a failure to form multinucleated myotubes, which were associated with dramatic increases in MDM2 expression and decrease in Rb protein levels. These results indicate that nutlin-3 can effectively inhibit muscle cell differentiation. - Highlights: • Nutlin-3 inhibits myoblast proliferation and prevents differentiation into myotubes. • Nutlin-3 increases MDM2 expression and down-regulates Rb protein levels. • This study has implication in nutlin-3 treatment of rhabdomyosarcomas.

  11. An automated high throughput screening-compatible assay to identify regulators of stem cell neural differentiation.

    Science.gov (United States)

    Casalino, Laura; Magnani, Dario; De Falco, Sandro; Filosa, Stefania; Minchiotti, Gabriella; Patriarca, Eduardo J; De Cesare, Dario

    2012-03-01

    The use of Embryonic Stem Cells (ESCs) holds considerable promise both for drug discovery programs and the treatment of degenerative disorders in regenerative medicine approaches. Nevertheless, the successful use of ESCs is still limited by the lack of efficient control of ESC self-renewal and differentiation capabilities. In this context, the possibility to modulate ESC biological properties and to obtain homogenous populations of correctly specified cells will help developing physiologically relevant screens, designed for the identification of stem cell modulators. Here, we developed a high throughput screening-suitable ESC neural differentiation assay by exploiting the Cell(maker) robotic platform and demonstrated that neural progenies can be generated from ESCs in complete automation, with high standards of accuracy and reliability. Moreover, we performed a pilot screening providing proof of concept that this assay allows the identification of regulators of ESC neural differentiation in full automation.

  12. Epigenetic landscapes reveal transcription factors that regulate CD8+ T cell differentiation.

    Science.gov (United States)

    Yu, Bingfei; Zhang, Kai; Milner, J Justin; Toma, Clara; Chen, Runqiang; Scott-Browne, James P; Pereira, Renata M; Crotty, Shane; Chang, John T; Pipkin, Matthew E; Wang, Wei; Goldrath, Ananda W

    2017-05-01

    Dynamic changes in the expression of transcription factors (TFs) can influence the specification of distinct CD8 + T cell fates, but the observation of equivalent expression of TFs among differentially fated precursor cells suggests additional underlying mechanisms. Here we profiled the genome-wide histone modifications, open chromatin and gene expression of naive, terminal-effector, memory-precursor and memory CD8 + T cell populations induced during the in vivo response to bacterial infection. Integration of these data suggested that the expression and binding of TFs contributed to the establishment of subset-specific enhancers during differentiation. We developed a new bioinformatics method using the PageRank algorithm to reveal key TFs that influence the generation of effector and memory populations. The TFs YY1 and Nr3c1, both constitutively expressed during CD8 + T cell differentiation, regulated the formation of terminal-effector cell fates and memory-precursor cell fates, respectively. Our data define the epigenetic landscape of differentiation intermediates and facilitate the identification of TFs with previously unappreciated roles in CD8 + T cell differentiation.

  13. NAD+ protects against EAE by regulating CD4+ T-cell differentiation

    Science.gov (United States)

    Tullius, Stefan G.; Biefer, Hector Rodriguez Cetina; Li, Suyan; Trachtenberg, Alexander J.; Edtinger, Karoline; Quante, Markus; Krenzien, Felix; Uehara, Hirofumi; Yang, Xiaoyong; Kissick, Haydn T.; Kuo, Winston P.; Ghiran, Ionita; de la Fuente, Miguel A.; Arredouani, Mohamed S.; Camacho, Virginia; Tigges, John C.; Toxavidis, Vasilis; El Fatimy, Rachid; Smith, Brian D.; Vasudevan, Anju; ElKhal, Abdallah

    2014-01-01

    CD4+ T cells are involved in the development of autoimmunity, including multiple sclerosis (MS). Here we show that nicotinamide adenine dinucleotide (NAD+) blocks experimental autoimmune encephalomyelitis (EAE), a mouse model of MS, by inducing immune homeostasis through CD4+IFNγ+IL-10+ T cells and reverses disease progression by restoring tissue integrity via remyelination and neuroregeneration. We show that NAD+ regulates CD4+ T-cell differentiation through tryptophan hydroxylase-1 (Tph1), independently of well-established transcription factors. In the presence of NAD+, the frequency of T-bet−/− CD4+IFNγ+ T cells was twofold higher than wild-type CD4+ T cells cultured in conventional T helper 1 polarizing conditions. Our findings unravel a new pathway orchestrating CD4+ T-cell differentiation and demonstrate that NAD+ may serve as a powerful therapeutic agent for the treatment of autoimmune and other diseases. PMID:25290058

  14. EZH2 regulates neuroblastoma cell differentiation via NTRK1 promoter epigenetic modifications.

    Science.gov (United States)

    Li, Zhenghao; Takenobu, Hisanori; Setyawati, Amallia Nuggetsiana; Akita, Nobuhiro; Haruta, Masayuki; Satoh, Shunpei; Shinno, Yoshitaka; Chikaraishi, Koji; Mukae, Kyosuke; Akter, Jesmin; Sugino, Ryuichi P; Nakazawa, Atsuko; Nakagawara, Akira; Aburatani, Hiroyuki; Ohira, Miki; Kamijo, Takehiko

    2018-05-01

    The polycomb repressor complex 2 molecule EZH2 is now known to play a role in essential cellular processes, namely, cell fate decisions, cell cycle regulation, senescence, cell differentiation, and cancer development/progression. EZH2 inhibitors have recently been developed; however, their effectiveness and underlying molecular mechanisms in many malignancies have not yet been elucidated in detail. Although the functional role of EZH2 in tumorigenesis in neuroblastoma (NB) has been investigated, mutations of EZH2 have not been reported. A Kaplan-Meier analysis on the event free survival and overall survival of NB patients indicated that the high expression of EZH2 correlated with an unfavorable prognosis. In order to elucidate the functional roles of EZH2 in NB tumorigenesis and its aggressiveness, we knocked down EZH2 in NB cell lines using lentivirus systems. The knockdown of EZH2 significantly induced NB cell differentiation, e.g., neurite extension, and the neuronal differentiation markers, NF68 and GAP43. EZH2 inhibitors also induced NB cell differentiation. We performed a comprehensive transcriptome analysis using Human Gene Expression Microarrays and found that NTRK1 (TrkA) is one of the EZH2-related suppression targets. The depletion of NTRK1 canceled EZH2 knockdown-induced NB cell differentiation. Our integrative methylome, transcriptome, and chromatin immunoprecipitation assays using NB cell lines and clinical samples clarified that the NTRK1 P1 and P2 promoter regions were regulated differently by DNA methylation and EZH2-related histone modifications. The NTRK1 transcript variants 1/2, which were regulated by EZH2-related H3K27me3 modifications at the P1 promoter region, were strongly expressed in favorable, but not unfavorable NB. The depletion and inhibition of EZH2 successfully induced NTRK1 transcripts and functional proteins. Collectively, these results indicate that EZH2 plays important roles in preventing the differentiation of NB cells and also

  15. Leptin differentially regulate STAT3 activation in ob/ob mouse adipose mesenchymal stem cells

    Directory of Open Access Journals (Sweden)

    Zhou Zhou

    2012-12-01

    Full Text Available Abstract Background Leptin-deficient ob/ob mice exhibit adipocyte hypertrophy and hyperplasia as well as elevated adipose tissue and systemic inflammation. Multipotent stem cells isolated from adult adipose tissue can differentiate into adipocytes ex vivo and thereby contribute toward increased adipocyte cell numbers, obesity, and inflamm ation. Currently, information is lacking regarding regulation of adipose stem cell numbers as well as leptin-induced inflammation and its signaling pathway in ob/ob mice. Methods Using leptin deficient ob/ob mice, we investigated whether leptin injection into ob/ob mice increases adipose stem cell numbers and adipose tissue inflammatory marker MCP-1 mRNA and secretion levels. We also determined leptin mediated signaling pathways in the adipose stem cells. Results We report here that adipose stem cell number is significantly increased following leptin injection in ob/ob mice and with treatment of isolated stem cells with leptin in vitro. Leptin also up-regulated MCP-1 secretion in a dose- and time-dependent manner. We further showed that increased MCP-1 mRNA levels were due to increased phosphorylation of Signal Transducer and Activator of Transcription 3 (STAT3 Ser727 but not STAT3 Tyr705 phosphorylation, suggesting differential regulation of MCP-1 gene expression under basal and leptin-stimulated conditions in adipose stem cells. Conclusions Taken together, these studies demonstrate that leptin increases adipose stem cell number and differentially activates STAT3 protein resulting in up-regulation of MCP-1 gene expression. Further studies of mechanisms mediating adipose stem cell hyperplasia and leptin signaling in obesity are warranted and may help identify novel anti-obesity target strategies.

  16. Local Inflammatory Cues Regulate Differentiation and Persistence of CD8+ Tissue-Resident Memory T Cells

    Directory of Open Access Journals (Sweden)

    Tessa Bergsbaken

    2017-04-01

    Full Text Available Many pathogens initiate infection at mucosal surfaces, and tissue-resident memory T (Trm cells play an important role in protective immunity, yet the tissue-specific signals that regulate Trm differentiation are poorly defined. During Yersinia infection, CD8+ T cell recruitment to areas of inflammation within the intestine is required for differentiation of the CD103−CD69+ Trm subset. Intestinal proinflammatory microenvironments have elevated interferon (IFN-β and interleukin-12 (IL-12, which regulated Trm markers, including CD103. Type I interferon-receptor- or IL-12-receptor-deficient T cells functioned similarly to wild-type (WT cells during infection; however, the inability of T cells to respond to inflammation resulted in defective differentiation of CD103−CD69+ Trm cells and reduced Trm persistence. Intestinal macrophages were the main producers of IFN-β and IL-12 during infection, and deletion of CCR2+ IL-12-producing cells reduced the size of the CD103− Trm population. These data indicate that intestinal inflammation drives phenotypic diversity and abundance of Trm cells for optimal tissue-specific immunity.

  17. Gammaherpesvirus-driven plasma cell differentiation regulates virus reactivation from latently infected B lymphocytes.

    Directory of Open Access Journals (Sweden)

    Xiaozhen Liang

    2009-11-01

    Full Text Available Gammaherpesviruses chronically infect their host and are tightly associated with the development of lymphoproliferative diseases and lymphomas, as well as several other types of cancer. Mechanisms involved in maintaining chronic gammaherpesvirus infections are poorly understood and, in particular, little is known about the mechanisms involved in controlling gammaherpesvirus reactivation from latently infected B cells in vivo. Recent evidence has linked plasma cell differentiation with reactivation of the human gammaherpesviruses EBV and KSHV through induction of the immediate-early viral transcriptional activators by the plasma cell-specific transcription factor XBP-1s. We now extend those findings to document a role for a gammaherpesvirus gene product in regulating plasma cell differentiation and thus virus reactivation. We have previously shown that the murine gammaherpesvirus 68 (MHV68 gene product M2 is dispensable for virus replication in permissive cells, but plays a critical role in virus reactivation from latently infected B cells. Here we show that in mice infected with wild type MHV68, virus infected plasma cells (ca. 8% of virus infected splenocytes at the peak of viral latency account for the majority of reactivation observed upon explant of splenocytes. In contrast, there is an absence of virus infected plasma cells at the peak of latency in mice infected with a M2 null MHV68. Furthermore, we show that the M2 protein can drive plasma cell differentiation in a B lymphoma cell line in the absence of any other MHV68 gene products. Thus, the role of M2 in MHV68 reactivation can be attributed to its ability to manipulate plasma cell differentiation, providing a novel viral strategy to regulate gammaherpesvirus reactivation from latently infected B cells. We postulate that M2 represents a new class of herpesvirus gene products (reactivation conditioners that do not directly participate in virus replication, but rather facilitate virus

  18. Gammaherpesvirus-driven plasma cell differentiation regulates virus reactivation from latently infected B lymphocytes.

    Science.gov (United States)

    Liang, Xiaozhen; Collins, Christopher M; Mendel, Justin B; Iwakoshi, Neal N; Speck, Samuel H

    2009-11-01

    Gammaherpesviruses chronically infect their host and are tightly associated with the development of lymphoproliferative diseases and lymphomas, as well as several other types of cancer. Mechanisms involved in maintaining chronic gammaherpesvirus infections are poorly understood and, in particular, little is known about the mechanisms involved in controlling gammaherpesvirus reactivation from latently infected B cells in vivo. Recent evidence has linked plasma cell differentiation with reactivation of the human gammaherpesviruses EBV and KSHV through induction of the immediate-early viral transcriptional activators by the plasma cell-specific transcription factor XBP-1s. We now extend those findings to document a role for a gammaherpesvirus gene product in regulating plasma cell differentiation and thus virus reactivation. We have previously shown that the murine gammaherpesvirus 68 (MHV68) gene product M2 is dispensable for virus replication in permissive cells, but plays a critical role in virus reactivation from latently infected B cells. Here we show that in mice infected with wild type MHV68, virus infected plasma cells (ca. 8% of virus infected splenocytes at the peak of viral latency) account for the majority of reactivation observed upon explant of splenocytes. In contrast, there is an absence of virus infected plasma cells at the peak of latency in mice infected with a M2 null MHV68. Furthermore, we show that the M2 protein can drive plasma cell differentiation in a B lymphoma cell line in the absence of any other MHV68 gene products. Thus, the role of M2 in MHV68 reactivation can be attributed to its ability to manipulate plasma cell differentiation, providing a novel viral strategy to regulate gammaherpesvirus reactivation from latently infected B cells. We postulate that M2 represents a new class of herpesvirus gene products (reactivation conditioners) that do not directly participate in virus replication, but rather facilitate virus reactivation by

  19. Meis1 regulates Foxn4 expression during retinal progenitor cell differentiation

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    Mohammed M. Islam

    2013-09-01

    The transcription factor forkhead box N4 (Foxn4 is a key regulator in a variety of biological processes during development. In particular, Foxn4 plays an essential role in the genesis of horizontal and amacrine neurons from neural progenitors in the vertebrate retina. Although the functions of Foxn4 have been well established, the transcriptional regulation of Foxn4 expression during progenitor cell differentiation remains unclear. Here, we report that an evolutionarily conserved 129 bp noncoding DNA fragment (Foxn4CR4.2 or CR4.2, located ∼26 kb upstream of Foxn4 transcription start site, functions as a cis-element for Foxn4 regulation. CR4.2 directs gene expression in Foxn4-positive cells, primarily in progenitors, differentiating horizontal and amacrine cells. We further determined that the gene regulatory activity of CR4.2 is modulated by Meis1 binding motif, which is bound and activated by Meis1 transcription factor. Deletion of the Meis1 binding motif or knockdown of Meis1 expression abolishes the gene regulatory activity of CR4.2. In addition, knockdown of Meis1 expression diminishes the endogenous Foxn4 expression and affects cell lineage development. Together, we demonstrate that CR4.2 and its interacting Meis1 transcription factor play important roles in regulating Foxn4 expression during early retinogenesis. These findings provide new insights into molecular mechanisms that govern gene regulation in retinal progenitors and specific cell lineage development.

  20. RNF20 and USP44 regulate stem cell differentiation by modulating H2B monoubiquitylation

    Science.gov (United States)

    Fuchs, Gilad; Shema, Efrat; Vesterman, Rita; Kotler, Eran; Wolchinsky, Zohar; Wilder, Sylvia; Golomb, Lior; Pribluda, Ariel; Zhang, Feng; Haj-Yahya, Mahmood; Feldmesser, Ester; Brik, Ashraf; Yu, Xiaochun; Hanna, Jacob; Aberdam, Daniel; Domany, Eytan; Oren, Moshe

    2012-01-01

    Summary Embryonic stem cells (ESC) maintain high genomic plasticity, essential for their capacity to enter diverse differentiation pathways. Post-transcriptional modifications of chromatin histones play a pivotal role in maintaining this plasticity. We now report that one such modification, monoubiquitylation of histone H2B on lysine 120 (H2Bub1), catalyzed by the E3 ligase RNF20, increases during ESC differentiation and is required for efficient execution of this process. This increase is particularly important for the transcriptional induction of relatively long genes during ESC differentiation. Furthermore, we identify the deubiquitinase USP44 as a negative regulator of H2B ubiquitylation, whose downregulation during ESC differentiation contributes to the increase in H2Bub1. Our findings suggest that optimal ESC differentiation requires dynamic changes in H2B ubiquitylation patterns, which must occur in a timely and well-coordinated manner. PMID:22681888

  1. HIF-1α as a Regulator of BMP2-Induced Chondrogenic Differentiation, Osteogenic Differentiation, and Endochondral Ossification in Stem Cells

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    Nian Zhou

    2015-04-01

    Full Text Available Background/Aims: Joint cartilage defects are difficult to treat due to the limited self-repair capacities of cartilage. Cartilage tissue engineering based on stem cells and gene enhancement is a potential alternative for cartilage repair. Bone morphogenetic protein 2 (BMP2 has been shown to induce chondrogenic differentiation in mesenchymal stem cells (MSCs; however, maintaining the phenotypes of MSCs during cartilage repair since differentiation occurs along the endochondral ossification pathway. In this study, hypoxia inducible factor, or (HIF-1α, was determined to be a regulator of BMP2-induced chondrogenic differentiation, osteogenic differentiation, and endochondral bone formation. Methods: BMP2 was used to induce chondrogenic and osteogenic differentiation in stem cells and fetal limb development. After HIF-1α was added to the inducing system, any changes in the differentiation markers were assessed. Results: HIF-1α was found to potentiate BMP2-induced Sox9 and the expression of chondrogenesis by downstream markers, and inhibit Runx2 and the expression of osteogenesis by downstream markers in vitro. In subcutaneous stem cell implantation studies, HIF-1α was shown to potentiate BMP2-induced cartilage formation and inhibit endochondral ossification during ectopic bone/cartilage formation. In the fetal limb culture, HIF-1α and BMP2 synergistically promoted the expansion of the proliferating chondrocyte zone and inhibited chondrocyte hypertrophy and endochondral ossification. Conclusion: The results of this study indicated that, when combined with BMP2, HIF-1α induced MSC differentiation could become a new method of maintaining cartilage phenotypes during cartilage tissue engineering.

  2. Epigenetic landscapes reveal transcription factors regulating CD8+ T cell differentiation

    Science.gov (United States)

    Yu, Bingfei; Zhang, Kai; Milner, J. Justin; Toma, Clara; Chen, Runqiang; Scott-Browne, James P.; Pereira, Renata M.; Crotty, Shane; Chang, John T.; Pipkin, Matthew E.; Wang, Wei; Goldrath, Ananda W.

    2017-01-01

    Dynamic changes in the expression of transcription factors (TFs) can influence specification of distinct CD8+ T cell fates, but the observation of equivalent expression of TF among differentially-fated precursor cells suggests additional underlying mechanisms. Here, we profiled genome-wide histone modifications, open chromatin and gene expression of naive, terminal-effector, memory-precursor and memory CD8+ T cell populations induced during the in vivo response to bacterial infection. Integration of these data suggested that TF expression and binding contributed to establishment of subset-specific enhancers during differentiation. We developed a new bioinformatics method using the PageRank algorithm to reveal novel TFs influencing the generation of effector and memory populations. The TFs YY1 and Nr3c1, both constitutively expressed during CD8+ T cell differentiation, regulated the formation of terminal-effector and memory-precursor cell-fates, respectively. Our data define the epigenetic landscape of differentiation intermediates, facilitating identification of TFs with previously unappreciated roles in CD8+ T cell differentiation. PMID:28288100

  3. Regulation of human skeletal stem cells differentiation by Dlk1/Pref-1

    DEFF Research Database (Denmark)

    Abdallah, Basem M; Jensen, Charlotte H; Gutierrez, Gloria

    2004-01-01

    Dlk-1/Pref-1 was identified as a novel regulator of human skeletal stem cell differentiation. Dlk1/Pref-1 is expressed in bone and cultured osteoblasts, and its constitutive overexpression led to inhibition of osteoblast and adipocyte differentiation of human marrow stromal cells. INTRODUCTION......: Molecular control of human mesenchymal stem cell (hMSC) differentiation into osteoblasts and adipocytes is not known. In this study, we examined the role of delta-like 1/preadipocyte factor-1 (Dlk1/Pref-1) in regulating the differentiation of hMSCs. MATERIALS AND METHODS: As a model for hMSCs, we have...... was used to confirm the in vitro effect of Dlk/Pref-1 on bone formation. RESULTS: Dlk1/Pref-1 was found to be expressed in fetal and adult bone, hMSCs, and some osteoblastic cell lines. A retroviral vector containing the human Dlk1/Pref-1 cDNA was used to create a cell line (hMSC-dlk1) expressing high...

  4. Identification of novel regulators in T-cell differentiation of aplastic anemia patients

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    Probst-Kepper Michael

    2006-10-01

    Full Text Available Abstract Background Aplastic anemia (AA is a bone marrow failure syndrome mostly characterized by an immune-mediated destruction of marrow hematopoietic progenitor/stem cells. The resulting hypocellularity limits a detailed analysis of the cellular immune response. To overcome this technical problem we performed a microarray analysis of CD3+ T-cells derived from bone marrow aspirates and peripheral blood samples of newly diagnosed AA patients and healthy volunteers. Two AA patients were additionally analyzed after achieving a partial remission following immunosuppression. The regulation of selected candidate genes was confirmed by real-time RT-PCR. Results Among more than 22.200 transcripts, 583 genes were differentially expressed in the bone marrow of AA patients compared to healthy controls. Dysregulated genes are involved in T-cell mediated cytotoxicity, immune response of Th1 differentiated T-cells, and major regulators of immune function. In hematological remission the expression levels of several candidate genes tend to normalize, such as immune regulators and genes involved in proinflammatory immune response. Conclusion Our study suggests a pivotal role of Th1/Tc1 differentiated T-cells in immune-mediated marrow destruction of AA patients. Most importantly, immune regulatory genes could be identified, which are likely involved in the recovery of hematopoiesis and may help to design new therapeutic strategies in bone marrow failure syndromes.

  5. The hippo pathway promotes Notch signaling in regulation of cell differentiation, proliferation, and oocyte polarity.

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    Jianzhong Yu

    2008-03-01

    Full Text Available Specification of the anterior-posterior axis in Drosophila oocytes requires proper communication between the germ-line cells and the somatically derived follicular epithelial cells. Multiple signaling pathways, including Notch, contribute to oocyte polarity formation by controlling the temporal and spatial pattern of follicle cell differentiation and proliferation. Here we show that the newly identified Hippo tumor-suppressor pathway plays a crucial role in the posterior follicle cells in the regulation of oocyte polarity. Disruption of the Hippo pathway, including major components Hippo, Salvador, and Warts, results in aberrant follicle-cell differentiation and proliferation and dramatic disruption of the oocyte anterior-posterior axis. These phenotypes are related to defective Notch signaling in follicle cells, because misexpression of a constitutively active form of Notch alleviates the oocyte polarity defects. We also find that follicle cells defective in Hippo signaling accumulate the Notch receptor and display defects in endocytosis markers. Our findings suggest that the interaction between Hippo and classic developmental pathways such as Notch is critical to spatial and temporal regulation of differentiation and proliferation and is essential for development of the body axes in Drosophila.

  6. Proximity-Based Differential Single-Cell Analysis of the Niche to Identify Stem/Progenitor Cell Regulators.

    Science.gov (United States)

    Silberstein, Lev; Goncalves, Kevin A; Kharchenko, Peter V; Turcotte, Raphael; Kfoury, Youmna; Mercier, Francois; Baryawno, Ninib; Severe, Nicolas; Bachand, Jacqueline; Spencer, Joel A; Papazian, Ani; Lee, Dongjun; Chitteti, Brahmananda Reddy; Srour, Edward F; Hoggatt, Jonathan; Tate, Tiffany; Lo Celso, Cristina; Ono, Noriaki; Nutt, Stephen; Heino, Jyrki; Sipilä, Kalle; Shioda, Toshihiro; Osawa, Masatake; Lin, Charles P; Hu, Guo-Fu; Scadden, David T

    2016-10-06

    Physiological stem cell function is regulated by secreted factors produced by niche cells. In this study, we describe an unbiased approach based on the differential single-cell gene expression analysis of mesenchymal osteolineage cells close to, and further removed from, hematopoietic stem/progenitor cells (HSPCs) to identify candidate niche factors. Mesenchymal cells displayed distinct molecular profiles based on their relative location. We functionally examined, among the genes that were preferentially expressed in proximal cells, three secreted or cell-surface molecules not previously connected to HSPC biology-the secreted RNase angiogenin, the cytokine IL18, and the adhesion molecule Embigin-and discovered that all of these factors are HSPC quiescence regulators. Therefore, our proximity-based differential single-cell approach reveals molecular heterogeneity within niche cells and can be used to identify novel extrinsic stem/progenitor cell regulators. Similar approaches could also be applied to other stem cell/niche pairs to advance the understanding of microenvironmental regulation of stem cell function. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. Proximity-based differential single cell analysis of the niche to identify stem/progenitor cell regulators

    Science.gov (United States)

    Silberstein, Lev; Goncalves, Kevin A; Kharchenko, Peter V; Turcotte, Raphael; Kfoury, Youmna; Mercier, Francois; Baryawno, Ninib; Severe, Nicolas; Bachand, Jacqueline; Spencer, Joel; Papazian, Ani; Lee, Dongjun; Chitteti, Brahmananda Reddy; Srour, Edward F; Hoggatt, Jonathan; Tate, Tiffany; Celso, Cristina Lo; Ono, Noriaki; Nutt, Stephen; Heino, Jyrki; Sipilä, Kalle; Shioda, Toshihiro; Osawa, Masatake; Lin, Charles P; Hu, Guo-fu; Scadden, David T

    2016-01-01

    SUMMARY Physiological stem cell function is regulated by secreted factors produced by niche cells. In this study, we describe an unbiased approach based on differential single-cell gene expression analysis of mesenchymal osteolineage cells close to and further removed from hematopoietic stem/progenitor cells to identify candidate niche factors. Mesenchymal cells displayed distinct molecular profiles based on their relative location. Amongst the genes which were preferentially expressed in proximal cells, we functionally examined three secreted or cell surface molecules not previously connected to HSPC biology: the secreted RNase Angiogenin, the cytokine IL18 and the adhesion molecule Embigin and discovered that all of these factors are HSPC quiescence regulators. Our proximity-based differential single cell approach therefore reveals molecular heterogeneity within niche cells and can be used to identify novel extrinsic stem/progenitor cell regulators. Similar approaches could also be applied to other stem cell/niche pairs to advance understanding of microenvironmental regulation of stem cell function. PMID:27524439

  8. Adhesive and mechanical regulation of mesenchymal stem cell differentiation in human bone marrow and periosteum-derived progenitor cells

    Directory of Open Access Journals (Sweden)

    Jeroen Eyckmans

    2012-08-01

    It has previously been demonstrated that cell shape can influence commitment of human bone marrow-derived mesenchymal stem cells (hBMCs to adipogenic, osteogenic, chondrogenic, and other lineages. Human periosteum-derived cells (hPDCs exhibit multipotency similar to hBMCs, but hPDCs may offer enhanced potential for osteogenesis and chondrogenesis given their apparent endogenous role in bone and cartilage repair in vivo. Here, we examined whether hPDC differentiation is regulated by adhesive and mechanical cues comparable to that reported for hBMC differentiation. When cultured in the appropriate induction media, hPDCs at high cell seeding density demonstrated enhanced levels of adipogenic or chondrogenic markers as compared with hPDCs at low cell seeding density. Cell seeding density correlated inversely with projected area of cell spreading, and directly limiting cell spreading with micropatterned substrates promoted adipogenesis or chondrogenesis while substrates promoting cell spreading supported osteogenesis. Interestingly, cell seeding density influenced differentiation through both changes in cell shape and non-shape-mediated effects: density-dependent adipogenesis and chondrogenesis were regulated primarily by cell shape whereas non-shape effects strongly influenced osteogenic potential. Inhibition of cytoskeletal contractility by adding the Rho kinase inhibitor Y27632 further enhanced adipogenic differentiation and discouraged osteogenic differentiation of hPDCs. Together, our results suggest that multipotent lineage decisions of hPDCs are impacted by cell adhesive and mechanical cues, though to different extents than hBMCs. Thus, future studies of hPDCs and other primary stem cell populations with clinical potential should consider varying biophysical metrics for more thorough optimization of stem cell differentiation.

  9. MicroRNAs define distinct human neuroblastoma cell phenotypes and regulate their differentiation and tumorigenicity

    International Nuclear Information System (INIS)

    Samaraweera, Leleesha; Grandinetti, Kathryn B; Huang, Ruojun; Spengler, Barbara A; Ross, Robert A

    2014-01-01

    Neuroblastoma (NB) is the most common extracranial solid tumor in children. NB tumors and derived cell lines are phenotypically heterogeneous. Cell lines are classified by phenotype, each having distinct differentiation and tumorigenic properties. The neuroblastic phenotype is tumorigenic, has neuronal features and includes stem cells (I-cells) and neuronal cells (N-cells). The non-neuronal phenotype (S-cell) comprises cells that are non-tumorigenic with features of glial/smooth muscle precursor cells. This study identified miRNAs associated with each distinct cell phenotypes and investigated their role in regulating associated differentiation and tumorigenic properties. A miRNA microarray was performed on the three cell phenotypes and expression verified by qRT-PCR. miRNAs specific for certain cell phenotypes were modulated using miRNA inhibitors or stable transfection. Neuronal differentiation was induced by RA; non-neuronal differentiation by BrdU. Changes in tumorigenicity were assayed by soft agar colony forming ability. N-myc binding to miR-375 promoter was assayed by chromatin-immunoprecipitation. Unsupervised hierarchical clustering of miRNA microarray data segregated neuroblastic and non-neuronal cell lines and showed that specific miRNAs define each phenotype. qRT-PCR validation confirmed that increased levels of miR-21, miR-221 and miR-335 are associated with the non-neuronal phenotype, whereas increased levels of miR-124 and miR-375 are exclusive to neuroblastic cells. Downregulation of miR-335 in non-neuronal cells modulates expression levels of HAND1 and JAG1, known modulators of neuronal differentiation. Overexpression of miR-124 in stem cells induces terminal neuronal differentiation with reduced malignancy. Expression of miR-375 is exclusive for N-myc-expressing neuroblastic cells and is regulated by N-myc. Moreover, miR-375 downregulates expression of the neuronal-specific RNA binding protein HuD. Thus, miRNAs define distinct NB cell phenotypes

  10. Rac1 Regulates the Proliferation, Adhesion, Migration, and Differentiation of MDPC-23 Cells.

    Science.gov (United States)

    Ren, Jing; Liang, Guobin; Gong, Li; Guo, Bing; Jiang, Hongwei

    2017-04-01

    Stem cells are responsible for replacing damaged pulp tissue; therefore, promoting their survival and inducing their adhesion to dentin are vital. As a member of the Rho family of guanosine triphosphatases, Rac1 is an important regulator of osteoblast functions. However, little is known about its role in regenerative endodontic procedures. The current study examined the role of Rac1 in the proliferation, migration, and odontoblastic differentiation of MDPC-23 cells. MDPC-23 cells were transfected with small interfering RNA to knock down Rac1 expression, and then their proliferation, migration, adhesion, and odontoblastic differentiation were examined in vitro. MDPC-23 cells transfected with si-Rac1 exhibited the increased expression of several key odontogenic protein markers, including Dmp1, Dspp, Runx2, and alkaline phosphatase, as well as decreased proliferation and migration in vitro. The results suggest that Rac1 might regulate nuclear factor kappa B signaling in MDPC-23 cells. Rac1 may have vital roles in the proliferation, migration, adhesion, and odontoblastic differentiation of MDPC-23 cells. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  11. A VESICLE TRAFFICKING PROTEIN αSNAP REGULATES PANETH CELL DIFFERENTIATION IN VIVO

    Science.gov (United States)

    Lechuga, Susana; Naydenov, Nayden G.; Feygin, Alex; Jimenez, Antonio J.; Ivanov, Andrei I.

    2017-01-01

    A soluble N-ethylmaleimide-sensitive factor-attachment protein alpha (αSNAP) is a multifunctional scaffolding protein that regulates intracellular vesicle trafficking and signaling. In cultured intestinal epithelial cells, αSNAP has been shown to be essential for cell survival, motility, and adhesion; however, its physiologic functions in the intestinal mucosa remain unknown. In the present study, we used a mouse with a spontaneous hydrocephalus with hop gait (hyh) mutation of αSNAP to examine the roles of this trafficking protein in regulating intestinal epithelial homeostasis in vivo. Homozygous hyh mice demonstrated decreased expression of αSNAP protein in the intestinal epithelium, but did not display gross abnormalities of epithelial architecture in the colon and ileum. Such αSNAP depletion attenuated differentiation of small intestinal epithelial enteroids ex vivo. Furthermore, αSNAP-deficient mutant animals displayed reduced formation of lysozyme granules in small intestinal crypts and decreased expression of lysozyme and defensins in the intestinal mucosa, which is indicative of defects in Paneth cell differentiation. By contrast, development of Goblet cells, enteroendocrine cells, and assembly of enterocyte apical junctions was not altered in hyh mutant mice. Our data revealed a novel role of αSNAP in the intestinal Paneth cell differentiation in vivo. PMID:28359759

  12. A vesicle trafficking protein αSNAP regulates Paneth cell differentiation in vivo.

    Science.gov (United States)

    Lechuga, Susana; Naydenov, Nayden G; Feygin, Alex; Jimenez, Antonio J; Ivanov, Andrei I

    2017-05-13

    A soluble N-ethylmaleimide-sensitive factor-attachment protein alpha (αSNAP) is a multifunctional scaffolding protein that regulates intracellular vesicle trafficking and signaling. In cultured intestinal epithelial cells, αSNAP has been shown to be essential for cell survival, motility, and adhesion; however, its physiologic functions in the intestinal mucosa remain unknown. In the present study, we used a mouse with a spontaneous hydrocephalus with hop gait (hyh) mutation of αSNAP to examine the roles of this trafficking protein in regulating intestinal epithelial homeostasis in vivo. Homozygous hyh mice demonstrated decreased expression of αSNAP protein in the intestinal epithelium, but did not display gross abnormalities of epithelial architecture in the colon and ileum. Such αSNAP depletion attenuated differentiation of small intestinal epithelial enteroids ex vivo. Furthermore, αSNAP-deficient mutant animals displayed reduced formation of lysozyme granules in small intestinal crypts and decreased expression of lysozyme and defensins in the intestinal mucosa, which is indicative of defects in Paneth cell differentiation. By contrast, development of Goblet cells, enteroendocrine cells, and assembly of enterocyte apical junctions was not altered in hyh mutant mice. Our data revealed a novel role of αSNAP in the intestinal Paneth cell differentiation in vivo. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. DNER, an epigenetically modulated gene, regulates glioblastoma-derived neurosphere cell differentiation and tumor propagation.

    Science.gov (United States)

    Sun, Peng; Xia, Shuli; Lal, Bachchu; Eberhart, Charles G; Quinones-Hinojosa, Alfredo; Maciaczyk, Jarek; Matsui, William; Dimeco, Francesco; Piccirillo, Sara M; Vescovi, Angelo L; Laterra, John

    2009-07-01

    Neurospheres derived from glioblastoma (GBM) and other solid malignancies contain neoplastic stem-like cells that efficiently propagate tumor growth and resist cytotoxic therapeutics. The primary objective of this study was to use histone-modifying agents to elucidate mechanisms by which the phenotype and tumor-promoting capacity of GBM-derived neoplastic stem-like cells are regulated. Using established GBM-derived neurosphere lines and low passage primary GBM-derived neurospheres, we show that histone deacetylase (HDAC) inhibitors inhibit growth, induce differentiation, and induce apoptosis of neoplastic neurosphere cells. A specific gene product induced by HDAC inhibition, Delta/Notch-like epidermal growth factor-related receptor (DNER), inhibited the growth of GBM-derived neurospheres, induced their differentiation in vivo and in vitro, and inhibited their engraftment and growth as tumor xenografts. The differentiating and tumor suppressive effects of DNER, a noncanonical Notch ligand, contrast with the previously established tumor-promoting effects of canonical Notch signaling in brain cancer stem-like cells. Our findings are the first to implicate noncanonical Notch signaling in the regulation of neoplastic stem-like cells and suggest novel neoplastic stem cell targeting treatment strategies for GBM and potentially other solid malignancies.

  14. Cholesterol negatively regulates IL-9-producing CD8+ T cell differentiation and antitumor activity.

    Science.gov (United States)

    Ma, Xingzhe; Bi, Enguang; Huang, Chunjian; Lu, Yong; Xue, Gang; Guo, Xing; Wang, Aibo; Yang, Maojie; Qian, Jianfei; Dong, Chen; Yi, Qing

    2018-05-09

    CD8 + T cells can be polarized into IL-9-secreting (Tc9) cells. We previously showed that adoptive therapy using tumor-specific Tc9 cells generated stronger antitumor responses in mouse melanoma than classical Tc1 cells. To understand why Tc9 cells exert stronger antitumor responses, we used gene profiling to compare Tc9 and Tc1 cells. Tc9 cells expressed different levels of cholesterol synthesis and efflux genes and possessed significantly lower cholesterol content than Tc1 cells. Unique to Tc9, but not other CD8 + or CD4 + T cell subsets, manipulating cholesterol content in polarizing Tc9 cells significantly affected IL-9 expression and Tc9 differentiation and antitumor response in vivo. Mechanistic studies showed that IL-9 was indispensable for Tc9 cell persistence and antitumor effects, and cholesterol or its derivatives inhibited IL-9 expression by activating liver X receptors (LXRs), leading to LXR Sumoylation and reduced p65 binding to Il9 promoter. Our study identifies cholesterol as a critical regulator of Tc9 cell differentiation and function. © 2018 Ma et al.

  15. Myostatin acts as an autocrine/paracrine negative regulator in myoblast differentiation from human induced pluripotent stem cells.

    Science.gov (United States)

    Gao, Fei; Kishida, Tsunao; Ejima, Akika; Gojo, Satoshi; Mazda, Osam

    2013-02-08

    Myostatin, also known as growth differentiation factor (GDF-8), regulates proliferation of muscle satellite cells, and suppresses differentiation of myoblasts into myotubes via down-regulation of key myogenic differentiation factors including MyoD. Recent advances in stem cell biology have enabled generation of myoblasts from pluripotent stem cells, but it remains to be clarified whether myostatin is also involved in regulation of artificial differentiation of myoblasts from pluripotent stem cells. Here we show that the human induced pluripotent stem (iPS) cell-derived cells that were induced to differentiate into myoblasts expressed myostatin and its receptor during the differentiation. An addition of recombinant human myostatin (rhMyostatin) suppressed induction of MyoD and Myo5a, resulting in significant suppression of myoblast differentiation. The rhMyostatin treatment also inhibited proliferation of the cells at a later phase of differentiation. RNAi-mediated silencing of myostatin promoted differentiation of human iPS-derived embryoid body (EB) cells into myoblasts. These results strongly suggest that myostatin plays an important role in regulation of myoblast differentiation from iPS cells of human origin. The present findings also have significant implications for potential regenerative medicine for muscular diseases. Copyright © 2013 Elsevier Inc. All rights reserved.

  16. Dasatinib accelerates valproic acid-induced acute myeloid leukemia cell death by regulation of differentiation capacity.

    Directory of Open Access Journals (Sweden)

    Sook-Kyoung Heo

    Full Text Available Dasatinib is a compound developed for chronic myeloid leukemia as a multi-targeted kinase inhibitor against wild-type BCR-ABL and SRC family kinases. Valproic acid (VPA is an anti-epileptic drug that also acts as a class I histone deacetylase inhibitor. The aim of this research was to determine the anti-leukemic effects of dasatinib and VPA in combination and to identify their mechanism of action in acute myeloid leukemia (AML cells. Dasatinib was found to exert potent synergistic inhibitory effects on VPA-treated AML cells in association with G1 phase cell cycle arrest and apoptosis induction involving the cleavage of poly (ADP-ribose polymerase and caspase-3, -7 and -9. Dasatinib/VPA-induced cell death thus occurred via caspase-dependent apoptosis. Moreover, MEK/ERK and p38 MAPK inhibitors efficiently inhibited dasatinib/VPA-induced apoptosis. The combined effect of dasatinib and VPA on the differentiation capacity of AML cells was more powerful than the effect of each drug alone, being sufficiently strong to promote AML cell death through G1 cell cycle arrest and caspase-dependent apoptosis. MEK/ERK and p38 MAPK were found to control dasatinib/VPA-induced apoptosis as upstream regulators, and co-treatment with dasatinib and VPA to contribute to AML cell death through the regulation of differentiation capacity. Taken together, these results indicate that combined dasatinib and VPA treatment has a potential role in anti-leukemic therapy.

  17. Negative regulation of neuronal cell differentiation by INHAT subunit SET/TAF-Iβ.

    Science.gov (United States)

    Kim, Dong-Wook; Kim, Kee-Beom; Kim, Ji-Young; Lee, Kyu-Sun; Seo, Sang-Beom

    2010-09-24

    Epigenetic modification plays an important role in transcriptional regulation. As a subunit of the INHAT (inhibitor of histone acetyltransferases) complex, SET/TAF-Iβ evidences transcriptional repression activity. In this study, we demonstrate that SET/TAF-Iβ is abundantly expressed in neuronal tissues of Drosophila embryos. It is expressed at high levels prior to and in early stages of neuronal development, and gradually reduced as differentiation proceeds. SET/TAF-Iβ binds to the promoters of a subset of neuronal development markers and negatively regulates the transcription of these genes. The results of this study show that the knockdown of SET/TAF-Iβ by si-RNA induces neuronal cell differentiation, thus implicating SET/TAF-Iβ as a negative regulator of neuronal development. Copyright © 2010 Elsevier Inc. All rights reserved.

  18. Regulation of eukaryotic initiation factor 4AII by MyoD during murine myogenic cell differentiation.

    Directory of Open Access Journals (Sweden)

    Gabriela Galicia-Vázquez

    Full Text Available Gene expression during muscle cell differentiation is tightly regulated at multiple levels, including translation initiation. The PI3K/mTOR signalling pathway exerts control over protein synthesis by regulating assembly of eukaryotic initiation factor (eIF 4F, a heterotrimeric complex that stimulates recruitment of ribosomes to mRNA templates. One of the subunits of eIF4F, eIF4A, supplies essential helicase function during this phase of translation. The presence of two cellular eIF4A isoforms, eIF4AI and eIF4AII, has long thought to impart equivalent functions to eIF4F. However, recent experiments have alluded to distinct activities between them. Herein, we characterize distinct regulatory mechanisms between the eIF4A isoforms during muscle cell differentiation. We find that eIF4AI levels decrease during differentiation whereas eIF4AII levels increase during myofiber formation in a MyoD-dependent manner. This study characterizes a previously undefined mechanism for eIF4AII regulation in differentiation and highlights functional differences between eIF4AI and eIF4AII. Finally, RNAi-mediated alterations in eIF4AI and eIF4AII levels indicate that the myogenic process can tolerate short term reductions in eIF4AI or eIF4AII levels, but not both.

  19. Tissue transglutaminase (TG2 activity regulates osteoblast differentiation and mineralization in the SAOS-2 cell line

    Directory of Open Access Journals (Sweden)

    Xiaoxue Yin

    2012-08-01

    Full Text Available Tissue transglutaminase (type II, TG2 has long been postulated to directly promote skeletal matrix calcification and play an important role in ossification. However, limited information is available on the expression, function and modulating mechanism of TG2 during osteoblast differentiation and mineralization. To address these issues, we cultured the well-established human osteosarcoma cell line SAOS-2 with osteo-inductive conditioned medium and set up three time points (culture days 4, 7, and 14 to represent different stages of SAOS-2 differentiation. Osteoblast markers, mineralization, as well as TG2 expression and activity, were then assayed in each stage. Furthermore, we inhibited TG activity with cystamine and then checked SAOS-2 differentiation and mineralization in each stage. The results showed that during the progression of osteoblast differentiation SAOS-2 cells presented significantly high levels of osteocalcin (OC mRNA, bone morphogenetic protein-2 (BMP-2 and collagen I, significantly high alkaline phosphatase (ALP activity, and the increased formation of calcified matrix. With the same tendency, TG2 expression and activity were up-regulated. Furthermore, inhibition of TG activity resulted in a significant decrease of OC, collagen I, and BMP-2 mRNA and of ALP activity and mineralization. This study demonstrated that TG2 is involved in osteoblast differentiation and may play a role in the initiation and regulation of the mineralization processes. Moreover, the modulating effects of TG2 on osteoblasts may be related to BMP-2.

  20. The ROCK isoforms differentially regulate the morphological characteristics of carcinoma cells.

    Science.gov (United States)

    Jerrell, Rachel J; Leih, Mitchell J; Parekh, Aron

    2017-06-26

    Rho-associated kinase (ROCK) activity drives cell migration via actomyosin contractility. During invasion, individual cancer cells can transition between 2 modes of migration, mesenchymal and amoeboid. Changes in ROCK activity can cause a switch between these migration phenotypes which are defined by distinct morphologies. However, recent studies have shown that the ROCK isoforms are not functionally redundant as previously thought. Therefore, it is unclear whether the ROCK isoforms play different roles in regulating migration phenotypes. Here, we found that ROCK1 and ROCK2 differentially regulate carcinoma cell morphology resulting in intermediate phenotypes that share some mesenchymal and amoeboid characteristics. These findings suggest that the ROCK isoforms play unique roles in the phenotypic plasticity of mesenchymal carcinoma cells which may have therapeutic implications.

  1. PDK1 Is a Regulator of Epidermal Differentiation that Activates and Organizes Asymmetric Cell Division

    Directory of Open Access Journals (Sweden)

    Teruki Dainichi

    2016-05-01

    Full Text Available Asymmetric cell division (ACD in a perpendicular orientation promotes cell differentiation and organizes the stratified epithelium. However, the upstream cues regulating ACD have not been identified. Here, we report that phosphoinositide-dependent kinase 1 (PDK1 plays a critical role in establishing ACD in the epithelium. Production of phosphatidyl inositol triphosphate (PIP3 is localized to the apical side of basal cells. Asymmetric recruitment of atypical protein kinase C (aPKC and partitioning defective (PAR 3 is impaired in PDK1 conditional knockout (CKO epidermis. PDK1CKO keratinocytes do not undergo calcium-induced activation of aPKC or IGF1-induced activation of AKT and fail to differentiate. PDK1CKO epidermis shows decreased expression of Notch, a downstream effector of ACD, and restoration of Notch rescues defective expression of differentiation-induced Notch targets in vitro. We therefore propose that PDK1 signaling regulates the basal-to-suprabasal switch in developing epidermis by acting as both an activator and organizer of ACD and the Notch-dependent differentiation program.

  2. IL-13 regulates human nasal epithelial cell differentiation via H3K4me3 modification

    Directory of Open Access Journals (Sweden)

    Yu L

    2018-01-01

    Full Text Available Lei Yu,1 Na Li,1 Jisheng Zhang,2 Yan Jiang1 1Department of Otorhinolaryngology, 2Key Laboratory of Otolaryngology-Head and Neck Surgery, Affiliated Hospital of Qingdao University, Qingdao, China Introduction: Epigenetic regulation has been shown to play an important role in the development of inflammatory diseases, including chronic rhinosinusitis and nasal polyps. The latter are characterized by epithelial mis-differentiation and infiltration of inflammatory cytokines. H3K4me3 has been shown to be involved in regulating lineage commitment. However, the underlying mechanisms, especially in human nasal epithelial cells (HNEpC, remain underexplored. The objective of this study was to investigate the role of H3K4me3 in HNEpC differentiation treated with the Th2 cytokine IL-13. Patients and methods: The expression levels of mRNA and proteins were investigated using reverse transcription-polymerase chain reaction (RT-PCR assays and Western blot in nasal polyp tissues and human nasal epithelial cells respectively. We measured these levels of H3K4me3, MLL1 and targeted genes compared with control subjects.Results: We demonstrate that expression of H3K4me3 and its methyltransferase MLL1 was significantly upregulated in IL-13-treated HNEpC. This elevation was also observed in nasal polyps. Expression of cilia-related transcription factors FOXJ1 and DNAI2 decreased, while goblet cell-derived genes CLCA1 and MUC5a increased upon IL-13 treatment. Mechanistically, knockdown of MLL1 restored expression of these four genes induced by IL-13. Conclusion: These findings suggest that H3K4me3 is a critical regulator in control of nasal epithelial cell differentiation. MLL1 may be a potential therapeutic target for nasal inflammatory diseases. Keywords: IL-13, H3K4me3 modification, nasal epithelial cell, differentiation 

  3. 5-Azacytidine delivered by mesoporous silica nanoparticles regulates the differentiation of P19 cells into cardiomyocytes

    Science.gov (United States)

    Cheng, Jin; Ding, Qian; Wang, Jia; Deng, Lin; Yang, Lu; Tao, Lei; Lei, Haihong; Lu, Shaoping

    2016-01-01

    Heart disease is one of the deadliest diseases causing mortality due to the limited regenerative capability of highly differentiated cardiomyocytes. Stem cell-based therapy in tissue engineering is one of the most exciting and rapidly growing areas and raises promising prospects for cardiac repair. In this study, we have synthesized FITC-mesoporous silica nanoparticles (FMSNs) based on a sol-gel method (known as Stöber's method) as a drug delivery platform to transport 5-azacytidine in P19 embryonic carcinoma stem cells. The surfactant CTAB is utilized as a liquid crystal template to self-aggregate into micelles, resulting in the synthesis of MSNs. Based on the cell viability assay, treatment with FMSNs + 5-azacytidine resulted in much more significant inhibition of the proliferation than 5-azacytidine alone. To study the mechanism, we have tested the differentiation genes and cardiac marker genes in P19 cells and found that these genes have been up-regulated in P19 embryonic carcinoma stem cells treated with FMSNs + 5-azacytidine + poly(allylamine hydrochloride) (PAH), with the changes of histone modifications on the regulatory region. In conclusion, with FMSNs as drug delivery platforms, 5-azacytidine can be more efficiently delivered into stem cells and can be used to monitor and track the transfection process in situ to clarify their effects on stem cell functions and the differentiation process, which can serve as a promising tool in tissue engineering and other biomedical fields.

  4. Legumain Regulates Differentiation Fate of Human Bone Marrow Stromal Cells and Is Altered in Postmenopausal Osteoporosis

    Directory of Open Access Journals (Sweden)

    Abbas Jafari

    2017-02-01

    Full Text Available Secreted factors are a key component of stem cell niche and their dysregulation compromises stem cell function. Legumain is a secreted cysteine protease involved in diverse biological processes. Here, we demonstrate that legumain regulates lineage commitment of human bone marrow stromal cells and that its expression level and cellular localization are altered in postmenopausal osteoporotic patients. As shown by genetic and pharmacological manipulation, legumain inhibited osteoblast (OB differentiation and in vivo bone formation through degradation of the bone matrix protein fibronectin. In addition, genetic ablation or pharmacological inhibition of legumain activity led to precocious OB differentiation and increased vertebral mineralization in zebrafish. Finally, we show that localized increased expression of legumain in bone marrow adipocytes was inversely correlated with adjacent trabecular bone mass in a cohort of patients with postmenopausal osteoporosis. Our data suggest that altered proteolytic activity of legumain in the bone microenvironment contributes to decreased bone mass in postmenopausal osteoporosis.

  5. Molecular and Genetic Analysis of Hormone-Regulated Differential Cell Elongation in Arabidopsis

    Energy Technology Data Exchange (ETDEWEB)

    Ecker, Joseph R.

    2002-12-03

    The authors have utilized the response of Arabidopsis seedlings to the plant hormone ethylene to identify new genes involved in the regulation of ethylene biosynthesis, perception, signal transduction and differential cell growth. In building a genetic framework for the action of these genes, they developed a molecular model that has facilitated the understanding of the molecular requirements of ethylene for cell elongation processes. The ethylene response pathway in Arabidopsis appears to be primarily linear and is defined by the genes: ETR1, ETR2, ERS1, ERS2, EIN4, CTR1, EIN2, EIN3, EIN5 EIN6, and EIN. Downstream branches identified by the HLS1, EIR1, and AUX1 genes involve interactions with other hormonal (auxin) signals in the process of differential cell elongation in the hypocotyl hook. Cloning and characterization of HLS1 and three HLS1-LIKE genes in the laboratory has been supported under this award. HLS1 is required for differential elongation of cells in the hypocotyl and may act in the establishment of hormone gradients. Also during the award period, they have identified and begun preliminary characterization of two genes that genetically act upstream of the ethylene receptors. ETO1 and RAN1 encode negative regulators of ethylene biosynthesis and signaling respectively. Progress on the analysis of these genes along with HOOKLESS1 is described.

  6. Molecular and Genetic Analysis of Hormone-Regulated Differential Cell Elongation in Arabidopsis

    Energy Technology Data Exchange (ETDEWEB)

    Ecker, Joseph R.

    2005-09-15

    We have utilized the response of Arabidopsis seedlings to the plant hormone ethylene to identify new genes involved in the regulation of ethylene biosynthesis, perception, signal transduction and differential cell growth. In building a genetic framework for the action of these genes, we have developed a molecular model that has facilitated our understanding of the molecular requirements of ethylene for cell elongation processes. The ethylene response pathway in Arabidopsis appears to be primarily linear and is defined by the genes: ETR1, ETR2, ERS1, ERS2, EIN4, CTR1, EIN2, EIN3, EIN5, EIN6, and EIN. Downstream branches identified by the HLS1, EIR1, and AUX1 genes involve interactions with other hormonal (auxin) signals in the process of differential cell elongation in the hypocotyl hook. Cloning and characterization of HLS1 (and three HLL genes) and ETO1 (and ETOL genes) in my laboratory has been supported under this award. HLS1 is required for differential elongation of cells in the hypocotyl and may act in the establishment of hormone gradients. Also during the previous period, we have identified and characterized a gene that genetically acts upstream of the ethylene receptors. ETO1 encodes negative regulators of ethylene biosynthesis.

  7. microRNAs as regulators of adipogenic differentiation of mesenchymal stem cells.

    Science.gov (United States)

    Hamam, Dana; Ali, Dalia; Kassem, Moustapha; Aldahmash, Abdullah; Alajez, Nehad M

    2015-02-15

    microRNAs (miRNAs) constitute complex regulatory network, fine tuning the expression of a myriad of genes involved in different biological and physiological processes, including stem cell differentiation. Mesenchymal stem cells (MSCs) are multipotent stem cells present in the bone marrow stroma, and the stroma of many other tissues, and can give rise to a number of mesoderm-type cells including adipocytes and osteoblasts, which form medullary fat and bone tissues, respectively. The role of bone marrow fat in bone mass homeostasis is an area of intensive investigation with the aim of developing novel approaches for enhancing osteoblastic bone formation through inhibition of bone marrow fat formation. A number of recent studies have reported several miRNAs that enhance or inhibit adipogenic differentiation of MSCs and with potential use in microRNA-based therapy to regulate adipogenesis in the context of treating bone diseases and metabolic disorders. The current review focuses on miRNAs and their role in regulating adipogenic differentiation of MSCs.

  8. Characterization of the Methylation Status of Pax7 and Myogenic Regulator Factors in Cell Myogenic Differentiation.

    Science.gov (United States)

    Chao, Zhe; Zheng, Xin-Li; Sun, Rui-Ping; Liu, Hai-Long; Huang, Li-Li; Cao, Zong-Xi; Deng, Chang-Yan; Wang, Feng

    2016-07-01

    Epigenetic processes in the development of skeletal muscle have been appreciated for over a decade. DNA methylation is a major epigenetic modification important for regulating gene expression and suppressing spurious transcription. Up to now, the importance of epigenetic marks in the regulation of Pax7 and myogenic regulatory factors (MRFs) expression is far less explored. In the present study, semi-quantitative the real-time polymerase chain reaction (RT-PCR) analyses showed MyoD and Myf5 were expressed in activated and quiescent C2C12 cells. MyoG was expressed in a later stage of myogenesis. Pax7 was weakly expressed in differentiated C2C12 cells. To further understand the regulation of expression of these genes, the DNA methylation status of Pax7, MyoD, and Myf5 was determined by bisulfite sequencing PCR. During the C2C12 myoblasts fusion process, the changes of promoter and exon 1 methylation of Pax7, MyoD, and Myf5 genes were observed. In addition, an inverse relationship of low methylation and high expression was found. These results suggest that DNA methylation may be an important mechanism regulating Pax7 and MRFs transcription in cell myogenic differentiation.

  9. Retinoic acid receptor signalling directly regulates osteoblast and adipocyte differentiation from mesenchymal progenitor cells

    Energy Technology Data Exchange (ETDEWEB)

    Green, A.C. [St Vincent' s Institute, Fitzroy, Victoria 3065 (Australia); Department of Medicine at St. Vincent' s Hospital, The University of Melbourne, Victoria 3065 (Australia); Kocovski, P.; Jovic, T.; Walia, M.K. [St Vincent' s Institute, Fitzroy, Victoria 3065 (Australia); Chandraratna, R.A.S. [IO Therapeutics, Inc., Santa Ana, CA 92705 (United States); Martin, T.J.; Baker, E.K. [St Vincent' s Institute, Fitzroy, Victoria 3065 (Australia); Department of Medicine at St. Vincent' s Hospital, The University of Melbourne, Victoria 3065 (Australia); Purton, L.E., E-mail: lpurton@svi.edu.au [St Vincent' s Institute, Fitzroy, Victoria 3065 (Australia); Department of Medicine at St. Vincent' s Hospital, The University of Melbourne, Victoria 3065 (Australia)

    2017-01-01

    Low and high serum retinol levels are associated with increased fracture risk and poor bone health. We recently showed retinoic acid receptors (RARs) are negative regulators of osteoclastogenesis. Here we show RARs are also negative regulators of osteoblast and adipocyte differentiation. The pan-RAR agonist, all-trans retinoic acid (ATRA), directly inhibited differentiation and mineralisation of early osteoprogenitors and impaired the differentiation of more mature osteoblast populations. In contrast, the pan-RAR antagonist, IRX4310, accelerated differentiation of early osteoprogenitors. These effects predominantly occurred via RARγ and were further enhanced by an RARα agonist or antagonist, respectively. RAR agonists similarly impaired adipogenesis in osteogenic cultures. RAR agonist treatment resulted in significant upregulation of the Wnt antagonist, Sfrp4. This accompanied reduced nuclear and cytosolic β-catenin protein and reduced expression of the Wnt target gene Axin2, suggesting impaired Wnt/β-catenin signalling. To determine the effect of RAR inhibition in post-natal mice, IRX4310 was administered to male mice for 10 days and bones were assessed by µCT. No change to trabecular bone volume was observed, however, radial bone growth was impaired. These studies show RARs directly influence osteoblast and adipocyte formation from mesenchymal cells, and inhibition of RAR signalling in vivo impairs radial bone growth in post-natal mice. - Graphical abstract: Schematic shows RAR ligand regulation of osteoblast differentiation in vitro. RARγ antagonists±RARα antagonists promote osteoblast differentiation. RARγ and RARα agonists alone or in combination block osteoblast differentiation, which correlates with upregulation of Sfrp4, and downregulation of nuclear and cytosolic β-catenin and reduced expression of the Wnt target gene Axin2. Red arrows indicate effects of RAR agonists on mediators of Wnt signalling.

  10. Transcription factor KLF7 regulates differentiation of neuroectodermal and mesodermal cell lineages

    International Nuclear Information System (INIS)

    Caiazzo, Massimiliano; Colucci-D'Amato, Luca; Esposito, Maria T.; Parisi, Silvia; Stifani, Stefano; Ramirez, Francesco; Porzio, Umberto di

    2010-01-01

    Previous gene targeting studies in mice have implicated the nuclear protein Krueppel-like factor 7 (KLF7) in nervous system development while cell culture assays have documented its involvement in cell cycle regulation. By employing short hairpin RNA (shRNA)-mediated gene silencing, here we demonstrate that murine Klf7 gene expression is required for in vitro differentiation of neuroectodermal and mesodermal cells. Specifically, we show a correlation of Klf7 silencing with down-regulation of the neuronal marker microtubule-associated protein 2 (Map2) and the nerve growth factor (NGF) tyrosine kinase receptor A (TrkA) using the PC12 neuronal cell line. Similarly, KLF7 inactivation in Klf7-null mice decreases the expression of the neurogenic marker brain lipid-binding protein/fatty acid-binding protein 7 (BLBP/FABP7) in neural stem cells (NSCs). We also report that Klf7 silencing is detrimental to neuronal and cardiomyocytic differentiation of embryonic stem cells (ESCs), in addition to altering the adipogenic and osteogenic potential of mouse embryonic fibroblasts (MEFs). Finally, our results suggest that genes that are key for self-renewal of undifferentiated ESCs repress Klf7 expression in ESCs. Together with previous findings, these results provide evidence that KLF7 has a broad spectrum of regulatory functions, which reflect the discrete cellular and molecular contexts in which this transcription factor operates.

  11. Transcription factor KLF7 regulates differentiation of neuroectodermal and mesodermal cell lineages

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    Caiazzo, Massimiliano, E-mail: caiazzo@igb.cnr.it [Institute of Genetics and Biophysics ' A. Buzzati-Traverso,' CNR, 80131 Naples (Italy); Istituto di diagnosi e cura ' Hermitage Capodimonte,' 80131 Naples (Italy); Colucci-D' Amato, Luca, E-mail: luca.colucci@unina2.it [Institute of Genetics and Biophysics ' A. Buzzati-Traverso,' CNR, 80131 Naples (Italy); Dipartimento di Scienze della Vita, Seconda Universita di Napoli, 81100 Caserta (Italy); Esposito, Maria T., E-mail: maria_teresa.esposito@kcl.ac.uk [CEINGE Biotecnologie Avanzate, 80145 Naples (Italy); Parisi, Silvia, E-mail: parisi@ceinge.unina.it [CEINGE Biotecnologie Avanzate, 80145 Naples (Italy); Stifani, Stefano, E-mail: stefano.stifani@mcgill.ca [Centre for Neuronal Survival, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada H3A 2B4 (Canada); Ramirez, Francesco, E-mail: francesco.ramirez@mssm.edu [Department of Pharmacology and Systems Therapeutics, Mount Sinai School of Medicine, New York, NY 10029 (United States); Porzio, Umberto di, E-mail: diporzio@igb.cnr.it [Institute of Genetics and Biophysics ' A. Buzzati-Traverso,' CNR, 80131 Naples (Italy)

    2010-08-15

    Previous gene targeting studies in mice have implicated the nuclear protein Krueppel-like factor 7 (KLF7) in nervous system development while cell culture assays have documented its involvement in cell cycle regulation. By employing short hairpin RNA (shRNA)-mediated gene silencing, here we demonstrate that murine Klf7 gene expression is required for in vitro differentiation of neuroectodermal and mesodermal cells. Specifically, we show a correlation of Klf7 silencing with down-regulation of the neuronal marker microtubule-associated protein 2 (Map2) and the nerve growth factor (NGF) tyrosine kinase receptor A (TrkA) using the PC12 neuronal cell line. Similarly, KLF7 inactivation in Klf7-null mice decreases the expression of the neurogenic marker brain lipid-binding protein/fatty acid-binding protein 7 (BLBP/FABP7) in neural stem cells (NSCs). We also report that Klf7 silencing is detrimental to neuronal and cardiomyocytic differentiation of embryonic stem cells (ESCs), in addition to altering the adipogenic and osteogenic potential of mouse embryonic fibroblasts (MEFs). Finally, our results suggest that genes that are key for self-renewal of undifferentiated ESCs repress Klf7 expression in ESCs. Together with previous findings, these results provide evidence that KLF7 has a broad spectrum of regulatory functions, which reflect the discrete cellular and molecular contexts in which this transcription factor operates.

  12. Osteogenic differentiation of mesenchymal stem cells is regulated by osteocyte and osteoblast cells in a simplified bone niche

    Directory of Open Access Journals (Sweden)

    LM McNamara

    2012-01-01

    Full Text Available Mesenchymal stem cells (MSCs within their native environment of the stem cell niche in bone receive biochemical stimuli from surrounding cells. These stimuli likely influence how MSCs differentiate to become bone precursors. The ability of MSCs to undergo osteogenic differentiation is well established in vitro;however, the role of the natural cues from bone’s regulatory cells, osteocytes and osteoblasts in regulating the osteogenic differentiation of MSCs in vivo are unclear. In this study we delineate the role of biochemical signalling from osteocytes and osteoblasts, using conditioned media and co-culture experiments, to understand how they direct osteogenic differentiation of MSCs. Furthermore, the synergistic relationship between osteocytes and osteoblasts is examined by transwell co-culturing of MSCs with both simultaneously. Osteogenic differentiation of MSCs was quantified by monitoring alkaline phosphatase (ALP activity, calcium deposition and cell number. Intracellular ALP was found to peak earlier and there was greater calcium deposition when MSCs were co-cultured with osteocytes rather than osteoblasts, suggesting that osteocytes are more influential than osteoblasts in stimulating osteogenesis in MSCs. Osteoblasts initially stimulated an increase in the number of MSCs, but ultimately regulated MSC differentiation down the same pathway. Our novel co-culture system confirmed a synergistic relationship between osteocytes and osteoblasts in producing biochemical signals to stimulate the osteogenic differentiation of MSCs. This study provides important insights into the mechanisms at work within the native stem cell niche to stimulate osteogenic differentiation and outlines a possible role for the use of co-culture or conditioned media methodologies for tissue engineering applications.

  13. Clinical and pathogenetic interrelation between molecular regulation of apoptosis and cell differentiation in osteoarthritis

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    M A Kabalyk

    2018-02-01

    Full Text Available Aim. To determine clinical and pathogenetic relationship between the levels of apoptosis and growth and differentiation regulation (growth inhibitor 1 induced by oxidative stress, growth/differentiation factor 5 in osteoarthritis. Methods. In a rheumatology office of Vladivostok polyclinic №3 65 patients with knee osteoarthritis Kellgren grade 1-4 aged 66.5±8.0 years were examined. 25 healthy volunteers matched by sex and age without clinical and radiologic manifestations of osteoarthritis were included into control group. To measure concentration of the studied molecules in study patients’ blood, ELISA method was used. Results. Patients with osteoarthritis compared to control group had statistically significantly increased levels of Fas, growth/differentiation factor 5 and ratio of growth/differentiation factor 5/growth inhibitor 1 induced by oxidative stress. Fas levels were significantly lower in late stages 2-4 of osteoarthritis compared to stages 1 and 2. Growth/differentiation factor 5 level was lower in patients with stage 3-4 of osteoarthritis compared to stages 1 and 2. As radiologic signs of osteoarthritis progressed, decrease of the ratio of growth/differentiation factor 5/growth inhibitor 1 induced by oxidative stress, was registered which was significantly lower in stages 2 and 3 compared to stage 1. Conclusion. Extrinsic pathway of apoptosis plays a big role in forming pain syndrome in osteoarthritis, and its maintenance is provided by other mechanisms which include influence of oxidative stress via inhibition of cell cycle mediated by growth inhibitor 1 induced by oxidative stress, reduced involvement of growth/differentiation factor 5 in differentiation processes and regulation of protein synthesis of extracellular cartilaginous tissue matrix.

  14. miR-24-mediated down-regulation of H2AX suppresses DNA repair in terminally differentiated blood cells

    Science.gov (United States)

    Lal, Ashish; Pan, Yunfeng; Navarro, Francisco; Dykxhoorn, Derek M.; Moreau, Lisa; Meire, Eti; Bentwich, Zvi; Lieberman, Judy; Chowdhury, Dipanjan

    2010-01-01

    Terminally differentiated cells have reduced capacity to repair double strand breaks (DSB), but the molecular mechanism behind this down-regulation is unclear. Here we find that miR-24 is consistently up-regulated during post-mitotic differentiation of hematopoietic cell lines and regulates the histone variant H2AX, a key DSB repair protein that activates cell cycle checkpoint proteins and retains DSB repair factors at DSB foci. The H2AX 3’UTR contains conserved miR-24 binding sites regulated by miR-24. Both H2AX mRNA and protein are substantially reduced during hematopoietic cell terminal differentiation by miR-24 up-regulation both in in vitro differentiated cells and primary human blood cells. miR-24 suppression of H2AX renders cells hypersensitive to γ-irradiation and genotoxic drugs. Antagonizing miR-24 in differentiating cells protects them from DNA damage-induced cell death, while transfecting miR-24 mimics in dividing cells increases chromosomal breaks and unrepaired DNA damage and reduces viability in response to DNA damage. This DNA repair phenotype can be fully rescued by over-expressing miR-24-insensitive H2AX. Therefore, miR-24 up-regulation in post-replicative cells reduces H2AX and thereby renders them highly vulnerable to DNA damage. PMID:19377482

  15. Differentiation, distribution and gammadelta T cell-driven regulation of IL-22-producing T cells in tuberculosis.

    Directory of Open Access Journals (Sweden)

    Shuyu Yao

    2010-02-01

    Full Text Available Differentiation, distribution and immune regulation of human IL-22-producing T cells in infections remain unknown. Here, we demonstrated in a nonhuman primate model that M. tuberculosis infection resulted in apparent increases in numbers of T cells capable of producing IL-22 de novo without in vitro Ag stimulation, and drove distribution of these cells more dramatically in lungs than in blood and lymphoid tissues. Consistently, IL-22-producing T cells were visualized in situ in lung tuberculosis (TB granulomas by confocal microscopy and immunohistochemistry, indicating that mature IL-22-producing T cells were present in TB granuloma. Surprisingly, phosphoantigen HMBPP activation of Vgamma2Vdelta2 T cells down-regulated the capability of T cells to produce IL-22 de novo in lymphocytes from blood, lung/BAL fluid, spleen and lymph node. Up-regulation of IFNgamma-producing Vgamma2Vdelta2 T effector cells after HMBPP stimulation coincided with the down-regulated capacity of these T cells to produce IL-22 de novo. Importantly, anti-IFNgamma neutralizing Ab treatment reversed the HMBPP-mediated down-regulation effect on IL-22-producing T cells, suggesting that Vgamma2Vdelta2 T-cell-driven IFNgamma-networking function was the mechanism underlying the HMBPP-mediated down-regulation of the capability of T cells to produce IL-22. These novel findings raise the possibility to ultimately investigate the function of IL-22 producing T cells and to target Vgamma2Vdelta2 T cells for balancing potentially hyper-activating IL-22-producing T cells in severe TB.

  16. Wnt and Hedgehog Signaling Regulate the Differentiation of F9 Cells into Extraembryonic Endoderm

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    Gurjoth S. J. Deol

    2017-10-01

    Full Text Available Mouse F9 cells differentiate into primitive extraembryonic endoderm (PrE when treated with retinoic acid (RA, and this is accompanied by an up-regulation of Gata6. The role of the GATA6 network in PrE differentiation is known, and we have shown it directly activates Wnt6. Canonical Wnt/β-catenin signaling is required by F9 cells to differentiate to PrE, and this, like most developmental processes, requires input from one or more additional pathways. We found both RA and Gata6 overexpression, can induce the expression of Indian Hedgehog (Ihh and a subset of its target genes through Gli activation during PrE induction. Chemical activation of the Hh pathway using a Smoothened agonist (SAG also increased Gli reporter activity, and as expected, when Hh signaling was blocked with a Smoothened antagonist, cyclopamine, this RA-induced reporter activity was reduced. Interestingly, SAG alone failed to induce markers of PrE differentiation, and had no effect on Wnt/β-catenin-dependent TCF-LEF reporter activity. The expected increase in Wnt/β-catenin-dependent TCF-LEF reporter activity and PrE markers induced by RA was, however, blocked by cyclopamine. Finally, inhibiting GSK3 activity with BIO increased both TCF-LEF and Gli reporter activities. Together, we demonstrate the involvement of Hh signaling in the RA-induced differentiation of F9 cells into PrE, and while the activation of the Hh pathway itself is not sufficient, it as well as active Wnt/β-catenin are necessary for F9 cell differentiation.

  17. Angiotensin II Regulation of Proliferation, Differentiation, and Engraftment of Hematopoietic Stem Cells.

    Science.gov (United States)

    Kim, Seungbum; Zingler, Michael; Harrison, Jeffrey K; Scott, Edward W; Cogle, Christopher R; Luo, Defang; Raizada, Mohan K

    2016-03-01

    Emerging evidence indicates that differentiation and mobilization of hematopoietic cell are critical in the development and establishment of hypertension and hypertension-linked vascular pathophysiology. This, coupled with the intimate involvement of the hyperactive renin-angiotensin system in hypertension, led us to investigate the hypothesis that chronic angiotensin II (Ang II) infusion affects hematopoietic stem cell (HSC) regulation at the level of the bone marrow. Ang II infusion resulted in increases in hematopoietic stem/progenitor cells (83%) and long-term HSC (207%) in the bone marrow. Interestingly, increases of HSCs and long-term HSCs were more pronounced in the spleen (228% and 1117%, respectively). Furthermore, we observed higher expression of C-C chemokine receptor type 2 in these HSCs, indicating there was increased myeloid differentiation in Ang II-infused mice. This was associated with accumulation of C-C chemokine receptor type 2(+) proinflammatory monocytes in the spleen. In contrast, decreased engraftment efficiency of GFP(+) HSC was observed after Ang II infusion. Time-lapse in vivo imaging and in vitro Ang II pretreatment demonstrated that Ang II induces untimely proliferation and differentiation of the donor HSC resulting in diminished HSC engraftment and bone marrow reconstitution. We conclude that (1) chronic Ang II infusion regulates HSC proliferation, mediated by angiotensin receptor type 1a, (2) Ang II accelerates HSC to myeloid differentiation resulting in accumulation of C-C chemokine receptor type 2(+) HSCs and inflammatory monocytes in the spleen, and (3) Ang II impairs homing and reconstitution potentials of the donor HSCs. These observations highlight the important regulatory roles of Ang II on HSC proliferation, differentiation, and engraftment. © 2016 American Heart Association, Inc.

  18. MicroRNA let-7b regulates neural stem cell proliferation and differentiation by targeting nuclear receptor TLX signaling.

    Science.gov (United States)

    Zhao, Chunnian; Sun, GuoQiang; Li, Shengxiu; Lang, Ming-Fei; Yang, Su; Li, Wendong; Shi, Yanhong

    2010-02-02

    Neural stem cell self-renewal and differentiation is orchestrated by precise control of gene expression involving nuclear receptor TLX. Let-7b, a member of the let-7 microRNA family, is expressed in mammalian brains and exhibits increased expression during neural differentiation. However, the role of let-7b in neural stem cell proliferation and differentiation remains unknown. Here we show that let-7b regulates neural stem cell proliferation and differentiation by targeting the stem cell regulator TLX and the cell cycle regulator cyclin D1. Overexpression of let-7b led to reduced neural stem cell proliferation and increased neural differentiation, whereas antisense knockdown of let-7b resulted in enhanced proliferation of neural stem cells. Moreover, in utero electroporation of let-7b to embryonic mouse brains led to reduced cell cycle progression in neural stem cells. Introducing an expression vector of Tlx or cyclin D1 that lacks the let-7b recognition site rescued let-7b-induced proliferation deficiency, suggesting that both TLX and cyclin D1 are important targets for let-7b-mediated regulation of neural stem cell proliferation. Let-7b, by targeting TLX and cyclin D1, establishes an efficient strategy to control neural stem cell proliferation and differentiation.

  19. Regulation of human mesenchymal stem cells differentiation into chondrocytes in extracellular matrix-based hydrogel scaffolds.

    Science.gov (United States)

    Du, Mingchun; Liang, Hui; Mou, Chenchen; Li, Xiaoran; Sun, Jie; Zhuang, Yan; Xiao, Zhifeng; Chen, Bing; Dai, Jianwu

    2014-02-01

    To induce human mesenchymal stem cells (hMSCs) to differentiate into chondrocytes in three-dimensional (3D) microenvironments, we developed porous hydrogel scaffolds using the cartilage extracellular matrix (ECM) components of chondroitin sulfate (CS) and collagen (COL). The turbidity and viscosity experiments indicated hydrogel could form through pH-triggered co-precipitation when pH=2-3. Enzyme-linked immunosorbent assay (ELISA) confirmed the hydrogel scaffolds could controllably release growth factors as envisaged. Transforming growth factor-β (TGF-β) was released to stimulate hMSCs differentiation into chondrocytes; and then collagen binding domain-basic fibroblast growth factor (CBD-bFGF) was released to improve the differentiation and preserve the chondrocyte phenotype. In in vitro cell culture experiments, the differentiation processes were compared in different microenvironments: 2D culture in culture plate as control, 3D culture in the fabricated scaffolds without growth factors (CC), the samples with CBD-bFGF (CC-C), the samples with TGF-β (CC-T), the samples with CBD-bFGF/TGF-β (CC-CT). Real-time polymerase chain reaction (RT-PCR) revealed the hMSC marker genes of CD44 and CD105 decreased; at the same time the chondrocyte marker genes of collagen type II and aggrecan increased, especially in the CC-CT sample. Immunostaining results further confirmed the hMSC marker protein of CD 44 disappeared and the chondrocyte marker protein of collagen type II emerged over time in the CC-CT sample. These results imply the ECM-based hydrogel scaffolds with growth factors can supply suitable 3D cell niches for hMSCs differentiation into chondrocytes and the differentiation process can be regulated by the controllably released growth factors. Copyright © 2013 Elsevier B.V. All rights reserved.

  20. Differential regulation of cyclin-dependent kinase inhibitors in neuroblastoma cells

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    Qiao, Lan [Department of Pediatric Surgery, Vanderbilt University Medical Center, Nashville, TN 37232 (United States); Department of Pharmaceutical Sciences, Jilin University, Changchun 130021 (China); Paul, Pritha; Lee, Sora [Department of Pediatric Surgery, Vanderbilt University Medical Center, Nashville, TN 37232 (United States); Department of Cancer Biology, Vanderbilt University Medical Center, Nashville, TN 37232 (United States); Qiao, Jingbo [Department of Pediatric Surgery, Vanderbilt University Medical Center, Nashville, TN 37232 (United States); Wang, Yongsheng [Department of Pharmaceutical Sciences, Jilin University, Changchun 130021 (China); Chung, Dai H., E-mail: dai.chung@vanderbilt.edu [Department of Pediatric Surgery, Vanderbilt University Medical Center, Nashville, TN 37232 (United States); Department of Cancer Biology, Vanderbilt University Medical Center, Nashville, TN 37232 (United States)

    2013-05-31

    Highlights: •GRP-R signaling differentially regulated the expression of p21 and p27. •Silencing GRP/GRP-R downregulated p21, while p27 expression was upregulated. •Inhibition of GRP/GRP-R signaling enhanced PTEN expression, correlative to the increased expression of p27. •PTEN and p27 co-localized in cytoplasm and silencing PTEN decreased p27 expression. -- Abstract: Gastrin-releasing peptide (GRP) and its receptor (GRP-R) are highly expressed in undifferentiated neuroblastoma, and they play critical roles in oncogenesis. We previously reported that GRP activates the PI3K/AKT signaling pathway to promote DNA synthesis and cell cycle progression in neuroblastoma cells. Conversely, GRP-R silencing induces cell cycle arrest. Here, we speculated that GRP/GRP-R signaling induces neuroblastoma cell proliferation via regulation of cyclin-dependent kinase (CDK) inhibitors. Surprisingly, we found that GRP/GRP-R differentially induced expressions of p21 and p27. Silencing GRP/GRP-R decreased p21, but it increased p27 expressions in neuroblastoma cells. Furthermore, we found that the intracellular localization of p21 and p27 in the nuclear and cytoplasmic compartments, respectively. In addition, we found that GRP/GRP-R silencing increased the expression and accumulation of PTEN in the cytoplasm of neuroblastoma cells where it co-localized with p27, thus suggesting that p27 promotes the function of PTEN as a tumor suppressor by stabilizing PTEN in the cytoplasm. GRP/GRP-R regulation of CDK inhibitors and tumor suppressor PTEN may be critical for tumoriogenesis of neuroblastoma.

  1. Differential regulation of cyclin-dependent kinase inhibitors in neuroblastoma cells

    International Nuclear Information System (INIS)

    Qiao, Lan; Paul, Pritha; Lee, Sora; Qiao, Jingbo; Wang, Yongsheng; Chung, Dai H.

    2013-01-01

    Highlights: •GRP-R signaling differentially regulated the expression of p21 and p27. •Silencing GRP/GRP-R downregulated p21, while p27 expression was upregulated. •Inhibition of GRP/GRP-R signaling enhanced PTEN expression, correlative to the increased expression of p27. •PTEN and p27 co-localized in cytoplasm and silencing PTEN decreased p27 expression. -- Abstract: Gastrin-releasing peptide (GRP) and its receptor (GRP-R) are highly expressed in undifferentiated neuroblastoma, and they play critical roles in oncogenesis. We previously reported that GRP activates the PI3K/AKT signaling pathway to promote DNA synthesis and cell cycle progression in neuroblastoma cells. Conversely, GRP-R silencing induces cell cycle arrest. Here, we speculated that GRP/GRP-R signaling induces neuroblastoma cell proliferation via regulation of cyclin-dependent kinase (CDK) inhibitors. Surprisingly, we found that GRP/GRP-R differentially induced expressions of p21 and p27. Silencing GRP/GRP-R decreased p21, but it increased p27 expressions in neuroblastoma cells. Furthermore, we found that the intracellular localization of p21 and p27 in the nuclear and cytoplasmic compartments, respectively. In addition, we found that GRP/GRP-R silencing increased the expression and accumulation of PTEN in the cytoplasm of neuroblastoma cells where it co-localized with p27, thus suggesting that p27 promotes the function of PTEN as a tumor suppressor by stabilizing PTEN in the cytoplasm. GRP/GRP-R regulation of CDK inhibitors and tumor suppressor PTEN may be critical for tumoriogenesis of neuroblastoma

  2. MicroRNA-138 regulates osteogenic differentiation of human stromal (mesenchymal) stem cells in vivo

    Science.gov (United States)

    Eskildsen, Tilde; Taipaleenmäki, Hanna; Stenvang, Jan; Abdallah, Basem M.; Ditzel, Nicholas; Nossent, Anne Yael; Bak, Mads; Kauppinen, Sakari; Kassem, Moustapha

    2011-01-01

    Elucidating the molecular mechanisms that regulate human stromal (mesenchymal) stem cell (hMSC) differentiation into osteogenic lineage is important for the development of anabolic therapies for treatment of osteoporosis. MicroRNAs (miRNAs) are short, noncoding RNAs that act as key regulators of diverse biological processes by mediating translational repression or mRNA degradation of their target genes. Here, we show that miRNA-138 (miR-138) modulates osteogenic differentiation of hMSCs. miRNA array profiling and further validation by quantitative RT-PCR (qRT-PCR) revealed that miR-138 was down-regulated during osteoblast differentiation of hMSCs. Overexpression of miR-138 inhibited osteoblast differentiation of hMSCs in vitro, whereas inhibition of miR-138 function by antimiR-138 promoted expression of osteoblast-specific genes, alkaline phosphatase (ALP) activity, and matrix mineralization. Furthermore, overexpression of miR-138 reduced ectopic bone formation in vivo by 85%, and conversely, in vivo bone formation was enhanced by 60% when miR-138 was antagonized. Target prediction analysis and experimental validation by luciferase 3′ UTR reporter assay confirmed focal adhesion kinase, a kinase playing a central role in promoting osteoblast differentiation, as a bona fide target of miR-138. We show that miR-138 attenuates bone formation in vivo, at least in part by inhibiting the focal adhesion kinase signaling pathway. Our findings suggest that pharmacological inhibition of miR-138 by antimiR-138 could represent a therapeutic strategy for enhancing bone formation in vivo. PMID:21444814

  3. Donor lung derived myeloid and plasmacytoid dendritic cells differentially regulate T cell proliferation and cytokine production

    Directory of Open Access Journals (Sweden)

    Benson Heather L

    2012-03-01

    Full Text Available Abstract Background Direct allorecognition, i.e., donor lung-derived dendritic cells (DCs stimulating recipient-derived T lymphocytes, is believed to be the key mechanism of lung allograft rejection. Myeloid (cDCs and plasmacytoid (pDCs are believed to have differential effects on T cell activation. However, the roles of each DC type on T cell activation and rejection pathology post lung transplantation are unknown. Methods Using transgenic mice and antibody depletion techniques, either or both cell types were depleted in lungs of donor BALB/c mice (H-2d prior to transplanting into C57BL/6 mice (H-2b, followed by an assessment of rejection pathology, and pDC or cDC-induced proliferation and cytokine production in C57BL/6-derived mediastinal lymph node T cells (CD3+. Results Depleting either DC type had modest effect on rejection pathology and T cell proliferation. In contrast, T cells from mice that received grafts depleted of both DCs did not proliferate and this was associated with significantly reduced acute rejection scores compared to all other groups. cDCs were potent inducers of IFNγ, whereas both cDCs and pDCs induced IL-10. Both cell types had variable effects on IL-17A production. Conclusion Collectively, the data show that direct allorecognition by donor lung pDCs and cDCs have differential effects on T cell proliferation and cytokine production. Depletion of both donor lung cDC and pDC could prevent the severity of acute rejection episodes.

  4. Slit/Robo1 signaling regulates neural tube development by balancing neuroepithelial cell proliferation and differentiation

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Guang; Li, Yan; Wang, Xiao-yu [Key Laboratory for Regenerative Medicine of The Ministry of Education, Department of Histology and Embryology, School of Medicine, Jinan University, Guangzhou 510632 (China); Han, Zhe [Institute of Vascular Biological Sciences, Guangdong Pharmaceutical University, Guangzhou 510224 (China); Chuai, Manli [College of Life Sciences Biocentre, University of Dundee, Dundee DD1 5EH (United Kingdom); Wang, Li-jing [Institute of Vascular Biological Sciences, Guangdong Pharmaceutical University, Guangzhou 510224 (China); Ho Lee, Kenneth Ka [Stem Cell and Regeneration Thematic Research Programme, School of Biomedical Sciences, Chinese University of Hong Kong, Shatin (Hong Kong); Geng, Jian-guo, E-mail: jgeng@umich.edu [Institute of Vascular Biological Sciences, Guangdong Pharmaceutical University, Guangzhou 510224 (China); Department of Biologic and Materials Sciences, University of Michigan School of Dentistry, Ann Arbor, MI 48109 (United States); Yang, Xuesong, E-mail: yang_xuesong@126.com [Key Laboratory for Regenerative Medicine of The Ministry of Education, Department of Histology and Embryology, School of Medicine, Jinan University, Guangzhou 510632 (China)

    2013-05-01

    development by tightly coordinating cell proliferation and differentiation during neurulation. - Highlights: ► The role of Slit/Robo1 signaling was investigated with chick and mouse models. ► Disturbance of Slit/Robo1 signaling resulted in neural tube defects. ► Slit/Robo1 signaling regulated the proliferation of neural tube cells. ► Slit/Robo1 signaling modulated the differentiation of neural tube cells. ► Slit/Robo1 signaling balanced the proliferation and differentiation of neural tube.

  5. The lupus susceptibility gene Pbx1 regulates the balance between follicular helper T cell and regulatory T cell differentiation

    Science.gov (United States)

    Choi, Seung-Chul; Hutchinson, Tarun E.; Titov, Anton A.; Seay, Howard R.; Li, Shiwu; Brusko, Todd M.; Croker, Byron P.; Salek-Ardakani, Shahram; Morel, Laurence

    2016-01-01

    Pbx1 controls chromatin accessibility to a large number of genes and is entirely conserved between mice and humans. The Pbx1-d dominant negative isoform is more frequent in the CD4+ T cells from lupus patients than from healthy controls. Pbx1-d is associated with the production of autoreactive T cells in mice carrying the Sle1a1 lupus susceptibility locus. Transgenic expression of Pbx1-d in CD4+ T cells reproduced the phenotypes of Sle1a1 mice, with increased inflammatory functions of CD4+ T cells and impaired regulatory T cell homeostasis. Pbx1-d Tg also expanded the number of follicular helper T cells in a cell-intrinsic and antigen-specific manner that was enhanced in recall responses, and resulted in TH1-biased antibodies. Moreover, Pbx1-d Tg CD4+ T cells upregulated the expression of miR-10a, miR-21 and miR-155, which have been implicated in Treg and TFH cell homeostasis. Our results suggest that Pbx1-d impacts lupus development by regulating effector T cell differentiation and promoting TFH cells at the expense of Treg cells. In addition, our results identify Pbx1 as a novel regulator of CD4+ T cell effector function. PMID:27296664

  6. Nicotine induces cell proliferation in association with cyclin D1 up-regulation and inhibits cell differentiation in association with p53 regulation in a murine pre-osteoblastic cell line

    International Nuclear Information System (INIS)

    Sato, Tsuyoshi; Abe, Takahiro; Nakamoto, Norimichi; Tomaru, Yasuhisa; Koshikiya, Noboru; Nojima, Junya; Kokabu, Shoichiro; Sakata, Yasuaki; Kobayashi, Akio; Yoda, Tetsuya

    2008-01-01

    Recent studies have suggested that nicotine critically affects bone metabolism. Many studies have examined the effects of nicotine on proliferation and differentiation, but the underlying molecular mechanisms remain unclear. We examined cell cycle regulators involved in the proliferation and differentiation of MC3T3-E1 cells. Nicotine induced cell proliferation in association with p53 down-regulation and cyclin D1 up-regulation. In differentiated cells, nicotine reduced alkaline phosphatase activity and mineralized nodule formation in dose-dependent manners. Furthermore, p53 expression was sustained in nicotine-treated cells during differentiation. These findings indicate that nicotine promotes the cell cycle and inhibits differentiation in association with p53 regulation in pre-osteoblastic cells

  7. MicroRNA-1 Regulates the Differentiation of Adipose-Derived Stem Cells into Cardiomyocyte-Like Cells

    Directory of Open Access Journals (Sweden)

    Can Chen

    2018-01-01

    Full Text Available Stem cell transplantation is one of most valuable methods in the treatment of myocardial infarction, and adipose-derived stem cells (ASCs are becoming a hot topic in medical research. Previous studies have shown that ASCs can be differentiated into cardiomyocyte-like cells, but the efficiency and survival rates are low. We investigated the role and mechanism of microRNA-1 (miR-1 in the differentiation of ASCs into cardiomyocyte-like cells. ASCs and cardiomyocytes were isolated from neonatal rats. We constructed lentivirus for overexpressing miR-1 and used DAPT, an antagonist of the Notch1 pathway, for in vitro analyses. We performed cocultures with ASCs and cardiomyocytes. The differentiation efficiency of ASCs was detected by cell-specific surface antigens. Our results showed that miR-1 can promote the expression of Notch1 and reduce the expression of Hes1, a Notch pathway factor, and overexpression of miR-1 can promote the differentiation of ASCs into cardiomyocyte-like cells, which may occur by regulating Notch1 and Hes1.

  8. Oestrogen, an evolutionary conserved regulator of T cell differentiation and immune tolerance in jawed vertebrates?

    Science.gov (United States)

    Paiola, Matthieu; Knigge, Thomas; Duflot, Aurélie; Pinto, Patricia I S; Farcy, Emilie; Monsinjon, Tiphaine

    2018-07-01

    In teleosts, as in mammals, the immune system is tightly regulated by sexual steroid hormones, such as oestrogens. We investigated the effects of 17β-oestradiol on the expression of several genes related to T cell development and resulting T cell subpopulations in sea bass, Dicentrarchus labrax, for a primary lymphoid organ, the thymus, and two secondary lymphoid organs, the head-kidney and the spleen. In parallel, the oxidative burst capacity was assessed in leucocytes of the secondary lymphoid organs. Apoptosis- and proliferation-related genes, indicative of B and T cell clonal selection and lymphoid progenitor activity, were not affected by elevated oestrogen-levels. Sex-related oestrogen-responsiveness in T cell and antigen-presenting cell markers was observed, the expression of which was differentially induced by oestrogen-exposure in the three lymphoid organs. Remarkably, in the spleen, oestrogen increased regulatory T cell-related gene expression was associated with a decrease in oxidative burst capacity. To the best of our knowledge, this study indicates for the first time that physiological levels of oestrogen are likely to promote immune tolerance by modulating thymic function (i.e., T cell development and output) and peripheral T cells in teleosts, similar to previously reported oestrogenic effects in mammals. Copyright © 2018 Elsevier Ltd. All rights reserved.

  9. Resveratrol Differentially Regulates NAMPT and SIRT1 in Hepatocarcinoma Cells and Primary Human Hepatocytes

    Science.gov (United States)

    Schuster, Susanne; Penke, Melanie; Gorski, Theresa; Petzold-Quinque, Stefanie; Damm, Georg; Gebhardt, Rolf; Kiess, Wieland; Garten, Antje

    2014-01-01

    Resveratrol is reported to possess chemotherapeutic properties in several cancers. In this study, we wanted to investigate the molecular mechanisms of resveratrol-induced cell cycle arrest and apoptosis as well as the impact of resveratrol on NAMPT and SIRT1 protein function and asked whether there are differences in hepatocarcinoma cells (HepG2, Hep3B cells) and non-cancerous primary human hepatocytes. We found a lower basal NAMPT mRNA and protein expression in hepatocarcinoma cells compared to primary hepatocytes. In contrast, SIRT1 was significantly higher expressed in hepatocarcinoma cells than in primary hepatocytes. Resveratrol induced cell cycle arrest in the S- and G2/M- phase and apoptosis was mediated by activation of p53 and caspase-3 in HepG2 cells. In contrast to primary hepatocytes, resveratrol treated HepG2 cells showed a reduction of NAMPT enzymatic activity and increased p53 acetylation (K382). Resveratrol induced NAMPT release from HepG2 cells which was associated with increased NAMPT mRNA expression. This effect was absent in primary hepatocytes where resveratrol was shown to function as NAMPT and SIRT1 activator. SIRT1 inhibition by EX527 resembled resveratrol effects on HepG2 cells. Furthermore, a SIRT1 overexpression significantly decreased both p53 hyperacetylation and resveratrol-induced NAMPT release as well as S-phase arrest in HepG2 cells. We could show that NAMPT and SIRT1 are differentially regulated by resveratrol in hepatocarcinoma cells and primary hepatocytes and that resveratrol did not act as a SIRT1 activator in hepatocarcinoma cells. PMID:24603648

  10. Resveratrol differentially regulates NAMPT and SIRT1 in Hepatocarcinoma cells and primary human hepatocytes.

    Directory of Open Access Journals (Sweden)

    Susanne Schuster

    Full Text Available Resveratrol is reported to possess chemotherapeutic properties in several cancers. In this study, we wanted to investigate the molecular mechanisms of resveratrol-induced cell cycle arrest and apoptosis as well as the impact of resveratrol on NAMPT and SIRT1 protein function and asked whether there are differences in hepatocarcinoma cells (HepG2, Hep3B cells and non-cancerous primary human hepatocytes. We found a lower basal NAMPT mRNA and protein expression in hepatocarcinoma cells compared to primary hepatocytes. In contrast, SIRT1 was significantly higher expressed in hepatocarcinoma cells than in primary hepatocytes. Resveratrol induced cell cycle arrest in the S- and G2/M- phase and apoptosis was mediated by activation of p53 and caspase-3 in HepG2 cells. In contrast to primary hepatocytes, resveratrol treated HepG2 cells showed a reduction of NAMPT enzymatic activity and increased p53 acetylation (K382. Resveratrol induced NAMPT release from HepG2 cells which was associated with increased NAMPT mRNA expression. This effect was absent in primary hepatocytes where resveratrol was shown to function as NAMPT and SIRT1 activator. SIRT1 inhibition by EX527 resembled resveratrol effects on HepG2 cells. Furthermore, a SIRT1 overexpression significantly decreased both p53 hyperacetylation and resveratrol-induced NAMPT release as well as S-phase arrest in HepG2 cells. We could show that NAMPT and SIRT1 are differentially regulated by resveratrol in hepatocarcinoma cells and primary hepatocytes and that resveratrol did not act as a SIRT1 activator in hepatocarcinoma cells.

  11. Hypoxia and hypoxia-inducible factors as regulators of T cell development, differentiation, and function

    Science.gov (United States)

    McNamee, Eóin N.; Johnson, Darlynn Korns; Homann, Dirk

    2014-01-01

    Oxygen is a molecule that is central to cellular respiration and viability, yet there are multiple physiologic and pathological contexts in which cells experience conditions of insufficient oxygen availability, a state known as hypoxia. Given the metabolic challenges of a low oxygen environment, hypoxia elicits a range of adaptive responses at the cellular, tissue, and systemic level to promote continued survival and function. Within this context, T lymphocytes are a highly migratory cell type of the adaptive immune system that frequently encounters a wide range of oxygen tensions in both health and disease. It is now clear that oxygen availability regulates T cell differentiation and function, a response orchestrated in large part by the hypoxia-inducible factor transcription factors. Here, we discuss the physiologic scope of hypoxia and hypoxic signaling, the contribution of these pathways in regulating T cell biology, and current gaps in our understanding. Finally, we discuss how emerging therapies that modulate the hypoxic response may offer new modalities to alter T cell function and the outcome of acute and chronic pathologies. PMID:22961658

  12. Glial cell ceruloplasmin and hepcidin differentially regulate iron efflux from brain microvascular endothelial cells.

    Science.gov (United States)

    McCarthy, Ryan C; Kosman, Daniel J

    2014-01-01

    We have used an in vitro model system to probe the iron transport pathway across the brain microvascular endothelial cells (BMVEC) of the blood-brain barrier (BBB). This model consists of human BMVEC (hBMVEC) and C6 glioma cells (as an astrocytic cell line) grown in a transwell, a cell culture system commonly used to quantify metabolite flux across a cell-derived barrier. We found that iron efflux from hBMVEC through the ferrous iron permease ferroportin (Fpn) was stimulated by secretion of the soluble form of the multi-copper ferroxidase, ceruloplasmin (sCp) from the co-cultured C6 cells. Reciprocally, expression of sCp mRNA in the C6 cells was increased by neighboring hBMVEC. In addition, data indicate that C6 cell-secreted hepcidin stimulates internalization of hBMVEC Fpn but only when the end-feet projections characteristic of this glia-derived cell line are proximal to the endothelial cells. This hepcidin-dependent loss of Fpn correlated with knock-down of iron efflux from the hBMVEC; this result was consistent with the mechanism by which hepcidin regulates iron efflux in mammalian cells. In summary, the data support a model of iron trafficking across the BBB in which the capillary endothelium induce the underlying astrocytes to produce the ferroxidase activity needed to support Fpn-mediated iron efflux. Reciprocally, astrocyte proximity modulates the effective concentration of hepcidin at the endothelial cell membrane and thus the surface expression of hBMVEC Fpn. These results are independent of the source of hBMVEC iron (transferrin or non-transferrin bound) indicating that the model developed here is broadly applicable to brain iron homeostasis.

  13. Molecular and biophysical mechanisms regulating hypertrophic differentiation in chondrocytes and mesenchymal stem cells

    Directory of Open Access Journals (Sweden)

    D Studer

    2012-07-01

    Full Text Available Chondrocyte hypertrophy is one of the key physiological processes involved in the longitudinal growth of long bones, yet the regulation of hypertrophy is also becoming increasingly relevant for clinical application of mesenchymal stem cells (MSCs and screening for drugs to treat hypertrophic osteoarthritis. The extraordinary cell volume increase during hypertrophy is accompanied by an up-regulation of collagen X, matrix metalloproteinases (MMPs, and vascular endothelial growth factor (VEGF, all which are targets of the runt-related transcription factor 2 (Runx2. Many pathways, including parathyroid hormone-related protein (PTHrP/Indian Hedgehog, Wingless/Int (Wnt/β-catenin, and transforming growth factor beta (TGF-β/Sma and Mad Related Family (Smad pathways, can regulate hypertrophy, but factors as diverse as hypoxia, co-culture, epigenetics and biomaterial composition can also potently affect Runx2 expression. Control of hypertrophic differentiation can be exploited both for cartilage repair, where a stable phenotype is desired, but also in bone regeneration, where hypertrophic cartilage could act as a template for endochondral bone formation. We hope this review will motivate the design of novel engineered microenvironments for skeletal regeneration applications.

  14. Fluvastatin mediated breast cancer cell death: a proteomic approach to identify differentially regulated proteins in MDA-MB-231 cells.

    Directory of Open Access Journals (Sweden)

    Anantha Koteswararao Kanugula

    Full Text Available Statins are increasingly being recognized as anti-cancer agents against various cancers including breast cancer. To understand the molecular pathways targeted by fluvastatin and its differential sensitivity against metastatic breast cancer cells, we analyzed protein alterations in MDA-MB-231 cells treated with fluvastatin using 2-DE in combination with LC-MS/MS. Results revealed dys-regulation of 39 protein spots corresponding to 35 different proteins. To determine the relevance of altered protein profiles with breast cancer cell death, we mapped these proteins to major pathways involved in the regulation of cell-to-cell signaling and interaction, cell cycle, Rho GDI and proteasomal pathways using IPA analysis. Highly interconnected sub networks showed that vimentin and ERK1/2 proteins play a central role in controlling the expression of altered proteins. Fluvastatin treatment caused proteolysis of vimentin, a marker of epithelial to mesenchymal transition. This effect of fluvastatin was reversed in the presence of mevalonate, a downstream product of HMG-CoA and caspase-3 inhibitor. Interestingly, fluvastatin neither caused an appreciable cell death nor did modulate vimentin expression in normal mammary epithelial cells. In conclusion, fluvastatin alters levels of cytoskeletal proteins, primarily targeting vimentin through increased caspase-3- mediated proteolysis, thereby suggesting a role for vimentin in statin-induced breast cancer cell death.

  15. The T-ALL related gene BCL11B regulates the initial stages of human T-cell differentiation.

    Science.gov (United States)

    Ha, V L; Luong, A; Li, F; Casero, D; Malvar, J; Kim, Y M; Bhatia, R; Crooks, G M; Parekh, C

    2017-11-01

    The initial stages of T-cell differentiation are characterized by a progressive commitment to the T-cell lineage, a process that involves the loss of alternative (myelo-erythroid, NK, B) lineage potentials. Aberrant differentiation during these stages can result in T-cell acute lymphoblastic leukemia (T-ALL). However, the mechanisms regulating the initial stages of human T-cell differentiation are obscure. Through loss of function studies, we showed BCL11B, a transcription factor recurrently mutated T-ALL, is essential for T-lineage commitment, particularly the repression of NK and myeloid potentials, and the induction of T-lineage genes, during the initial stages of human T-cell differentiation. In gain of function studies, BCL11B inhibited growth of and induced a T-lineage transcriptional program in T-ALL cells. We found previously unknown differentiation stage-specific DNA binding of BCL11B at multiple T-lineage genes; target genes showed BCL11B-dependent expression, suggesting a transcriptional activator role for BCL11B at these genes. Transcriptional analyses revealed differences in the regulatory actions of BCL11B between human and murine thymopoiesis. Our studies show BCL11B is a key regulator of the initial stages of human T-cell differentiation and delineate the BCL11B transcriptional program, enabling the dissection of the underpinnings of normal T-cell differentiation and providing a resource for understanding dysregulations in T-ALL.

  16. Mechanically stimulated bone cells secrete paracrine factors that regulate osteoprogenitor recruitment, proliferation, and differentiation

    International Nuclear Information System (INIS)

    Brady, Robert T.; O'Brien, Fergal J.; Hoey, David A.

    2015-01-01

    Bone formation requires the recruitment, proliferation and osteogenic differentiation of mesenchymal progenitors. A potent stimulus driving this process is mechanical loading, yet the signalling mechanisms underpinning this are incompletely understood. The objective of this study was to investigate the role of the mechanically-stimulated osteocyte and osteoblast secretome in coordinating progenitor contributions to bone formation. Initially osteocytes (MLO-Y4) and osteoblasts (MC3T3) were mechanically stimulated for 24hrs and secreted factors within the conditioned media were collected and used to evaluate mesenchymal stem cell (MSC) and osteoblast recruitment, proliferation and osteogenesis. Paracrine factors secreted by mechanically stimulated osteocytes significantly enhanced MSC migration, proliferation and osteogenesis and furthermore significantly increased osteoblast migration and proliferation when compared to factors secreted by statically cultured osteocytes. Secondly, paracrine factors secreted by mechanically stimulated osteoblasts significantly enhanced MSC migration but surprisingly, in contrast to the osteocyte secretome, inhibited MSC proliferation when compared to factors secreted by statically cultured osteoblasts. A similar trend was observed in osteoblasts. This study provides new information on mechanically driven signalling mechanisms in bone and highlights a contrasting secretome between cells at different stages in the bone lineage, furthering our understanding of loading-induced bone formation and indirect biophysical regulation of osteoprogenitors. - Highlights: • Physically stimulated osteocytes secrete factors that regulate osteoprogenitors. • These factors enhance recruitment, proliferation and osteogenic differentiation. • Physically stimulated osteoblasts secrete factors that also regulate progenitors. • These factors enhance recruitment but inhibit proliferation of osteoprogenitors. • This study highlights a contrasting

  17. Mechanically stimulated bone cells secrete paracrine factors that regulate osteoprogenitor recruitment, proliferation, and differentiation

    Energy Technology Data Exchange (ETDEWEB)

    Brady, Robert T. [Tissue Engineering Research Group, Dept. of Anatomy, Royal College of Surgeons in Ireland (Ireland); Trinity Centre for Bioengineering, School of Engineering, Trinity College Dublin (Ireland); Advanced Materials and BioEngineering Research Centre (AMBER), Trinity College Dublin & Royal College of Surgeons in Ireland (Ireland); Dept. of Mechanical, Aeronautical and Biomedical Engineering, University of Limerick (Ireland); O' Brien, Fergal J. [Tissue Engineering Research Group, Dept. of Anatomy, Royal College of Surgeons in Ireland (Ireland); Trinity Centre for Bioengineering, School of Engineering, Trinity College Dublin (Ireland); Advanced Materials and BioEngineering Research Centre (AMBER), Trinity College Dublin & Royal College of Surgeons in Ireland (Ireland); Hoey, David A., E-mail: david.hoey@ul.ie [Trinity Centre for Bioengineering, School of Engineering, Trinity College Dublin (Ireland); Dept. of Mechanical, Aeronautical and Biomedical Engineering, University of Limerick (Ireland); The Centre for Applied Biomedical Engineering Research, University of Limerick (Ireland); Materials & Surface Science Institute, University of Limerick (Ireland)

    2015-03-27

    Bone formation requires the recruitment, proliferation and osteogenic differentiation of mesenchymal progenitors. A potent stimulus driving this process is mechanical loading, yet the signalling mechanisms underpinning this are incompletely understood. The objective of this study was to investigate the role of the mechanically-stimulated osteocyte and osteoblast secretome in coordinating progenitor contributions to bone formation. Initially osteocytes (MLO-Y4) and osteoblasts (MC3T3) were mechanically stimulated for 24hrs and secreted factors within the conditioned media were collected and used to evaluate mesenchymal stem cell (MSC) and osteoblast recruitment, proliferation and osteogenesis. Paracrine factors secreted by mechanically stimulated osteocytes significantly enhanced MSC migration, proliferation and osteogenesis and furthermore significantly increased osteoblast migration and proliferation when compared to factors secreted by statically cultured osteocytes. Secondly, paracrine factors secreted by mechanically stimulated osteoblasts significantly enhanced MSC migration but surprisingly, in contrast to the osteocyte secretome, inhibited MSC proliferation when compared to factors secreted by statically cultured osteoblasts. A similar trend was observed in osteoblasts. This study provides new information on mechanically driven signalling mechanisms in bone and highlights a contrasting secretome between cells at different stages in the bone lineage, furthering our understanding of loading-induced bone formation and indirect biophysical regulation of osteoprogenitors. - Highlights: • Physically stimulated osteocytes secrete factors that regulate osteoprogenitors. • These factors enhance recruitment, proliferation and osteogenic differentiation. • Physically stimulated osteoblasts secrete factors that also regulate progenitors. • These factors enhance recruitment but inhibit proliferation of osteoprogenitors. • This study highlights a contrasting

  18. MicroRNA-378 regulates neural stem cell proliferation and differentiation in vitro by modulating Tailless expression

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Yanxia [Department of Psychology and Psychiatry, The Second Affiliated Hospital of Xi' an Jiaotong University, Xi' an 710004 (China); Department of Rehabilitation, Xi' an Children' s Hospital, Xi' an 710003 (China); Liu, Xiaoguai [The 3rd Department of Infectious Diseases, Xi' an Children' s Hospital, Xi' an 710003 (China); Wang, Yaping, E-mail: yapwangyy@163.com [Department of Psychology and Psychiatry, The Second Affiliated Hospital of Xi' an Jiaotong University, Xi' an 710004 (China)

    2015-10-16

    Previous studies have suggested that microRNAs (miRNAs) play an important role in regulating neural stem cell (NSC) proliferation and differentiation. However, the precise role of miRNAs in NSC remains largely unexplored. In this study, we showed that miR-378 can target Tailless (TLX), a critical regulator of NSC, to regulate NSC proliferation and differentiation. By bioinformatic algorithms, miR-378 was found to have a predicted target site in the 3′-untranslated region of TLX, which was verified by a dual-luciferase reporter assay. The expression of miR-378 was increased during NSC differentiation and inversely correlated with TLX expression. qPCR and Western blot analysis also showed that miR-378 negatively regulated TLX mRNA and protein expression in neural stem cells (NSCs). Intriguingly, overexpression of miR-378 increased NSC differentiation and reduced NSC proliferation, whereas suppression of miR-378 led to decreased NSC differentiation and increased NSC proliferation. Moreover, the downstream targets of TLX, including p21, PTEN and Wnt/β-catenin were also found to be regulated by miR-378. Additionally, overexpression of TLX rescued the NSC proliferation deficiency induced by miR-378 overexpression and abolished miR-378-promoted NSC differentiation. Taken together, our data suggest that miR-378 is a novel miRNA that regulates NSC proliferation and differentiation via targeting TLX. Therefore, manipulating miR-378 in NSCs could be a novel strategy to develop novel interventions for the treatment of relevant neurological disorders. - Highlights: • miR-378 targeted and regulated TLX. • miR-378 was increased during NSC differentiation. • miR-378 regulated NSC proliferation and differentiation. • miR-378 regulated NSC self-renew through TLX.

  19. MicroRNA-378 regulates neural stem cell proliferation and differentiation in vitro by modulating Tailless expression

    International Nuclear Information System (INIS)

    Huang, Yanxia; Liu, Xiaoguai; Wang, Yaping

    2015-01-01

    Previous studies have suggested that microRNAs (miRNAs) play an important role in regulating neural stem cell (NSC) proliferation and differentiation. However, the precise role of miRNAs in NSC remains largely unexplored. In this study, we showed that miR-378 can target Tailless (TLX), a critical regulator of NSC, to regulate NSC proliferation and differentiation. By bioinformatic algorithms, miR-378 was found to have a predicted target site in the 3′-untranslated region of TLX, which was verified by a dual-luciferase reporter assay. The expression of miR-378 was increased during NSC differentiation and inversely correlated with TLX expression. qPCR and Western blot analysis also showed that miR-378 negatively regulated TLX mRNA and protein expression in neural stem cells (NSCs). Intriguingly, overexpression of miR-378 increased NSC differentiation and reduced NSC proliferation, whereas suppression of miR-378 led to decreased NSC differentiation and increased NSC proliferation. Moreover, the downstream targets of TLX, including p21, PTEN and Wnt/β-catenin were also found to be regulated by miR-378. Additionally, overexpression of TLX rescued the NSC proliferation deficiency induced by miR-378 overexpression and abolished miR-378-promoted NSC differentiation. Taken together, our data suggest that miR-378 is a novel miRNA that regulates NSC proliferation and differentiation via targeting TLX. Therefore, manipulating miR-378 in NSCs could be a novel strategy to develop novel interventions for the treatment of relevant neurological disorders. - Highlights: • miR-378 targeted and regulated TLX. • miR-378 was increased during NSC differentiation. • miR-378 regulated NSC proliferation and differentiation. • miR-378 regulated NSC self-renew through TLX.

  20. Regulation of B cell differentiation by intracellular membrane associated proteins and microRNAs: role in the antibody response

    Directory of Open Access Journals (Sweden)

    Zheng eLou

    2015-10-01

    Full Text Available B cells are central to adaptive immunity and their functions in antibody responses are exquisitely regulated. As suggested by recent findings, B cell differentiation is mediated by intracellular membrane structures (including endosomes, lysosomes and autophagosomes and protein factors specifically associated with these membranes, including Rab7, Atg5 and Atg7. These factors participate in vesicle formation/trafficking, signal transduction and induction of gene expression to promote antigen presentation, CSR/SHM, and generation/maintenance of plasma cells and memory B cells. Their expression is induced in B cells activated to differentiate and further fine-tuned by immune-modulating microRNAs, which coordinates CSR/SHM, plasma cell differentiation and memory B cell differentiation. These short non-coding RNAs would individually target multiple factors associated with the same intracellular membrane compartments and collaboratively target a single factor in addition to regulate AID and Blimp-1. These, together with regulation of microRNA biogenesis and activities by endosomes and autophagosomes, show that intracellular membranes and microRNAs, two broadly relevant cell constituents, play important roles in balancing gene expression to specify B cell differentiation processes for optimal antibody responses.

  1. Cyclooxygenase-2 Regulates Th17 Cell Differentiation during Allergic Lung Inflammation

    OpenAIRE

    Li, Hong; Bradbury, J. Alyce; Dackor, Ryan T.; Edin, Matthew L.; Graves, Joan P.; DeGraff, Laura M.; Wang, Ping Ming; Bortner, Carl D.; Maruoka, Shuichiro; Lih, Fred B.; Cook, Donald N.; Tomer, Kenneth B.; Jetten, Anton M.; Zeldin, Darryl C.

    2011-01-01

    Rationale: Th17 cells comprise a distinct lineage of proinflammatory T helper cells that are major contributors to allergic responses. It is unknown whether cyclooxygenase (COX)-derived eicosanoids regulate Th17 cells during allergic lung inflammation.

  2. Tlx3 exerts context-dependent transcriptional regulation and promotes neuronal differentiation from embryonic stem cells

    OpenAIRE

    Kondo, Takako; Sheets, Patrick L.; Zopf, David A.; Aloor, Heather L.; Cummins, Theodore R.; Chan, Rebecca J.; Hashino, Eri

    2008-01-01

    The T cell leukemia 3 (Tlx3) gene has been implicated in specification of glutamatergic sensory neurons in the spinal cord. In cranial sensory ganglia, Tlx3 is highly expressed in differentiating neurons during early embryogenesis. To study a role of Tlx3 during neural differentiation, mouse embryonic stem (ES) cells were transfected with a Tlx3 expression vector. ES cells stably expressing Tlx3 were grown in the presence or absence of a neural induction medium. In undifferentiated ES cells, ...

  3. SPDEF is required for mouse pulmonary goblet cell differentiation and regulates a network of genes associated with mucus production.

    Science.gov (United States)

    Chen, Gang; Korfhagen, Thomas R; Xu, Yan; Kitzmiller, Joseph; Wert, Susan E; Maeda, Yutaka; Gregorieff, Alexander; Clevers, Hans; Whitsett, Jeffrey A

    2009-10-01

    Various acute and chronic inflammatory stimuli increase the number and activity of pulmonary mucus-producing goblet cells, and goblet cell hyperplasia and excess mucus production are central to the pathogenesis of chronic pulmonary diseases. However, little is known about the transcriptional programs that regulate goblet cell differentiation. Here, we show that SAM-pointed domain-containing Ets-like factor (SPDEF) controls a transcriptional program critical for pulmonary goblet cell differentiation in mice. Initial cell-lineage-tracing analysis identified nonciliated secretory epithelial cells, known as Clara cells, as the progenitors of goblet cells induced by pulmonary allergen exposure in vivo. Furthermore, in vivo expression of SPDEF in Clara cells caused rapid and reversible goblet cell differentiation in the absence of cell proliferation. This was associated with enhanced expression of genes regulating goblet cell differentiation and protein glycosylation, including forkhead box A3 (Foxa3), anterior gradient 2 (Agr2), and glucosaminyl (N-acetyl) transferase 3, mucin type (Gcnt3). Consistent with these findings, levels of SPDEF and FOXA3 were increased in mouse goblet cells after sensitization with pulmonary allergen, and the proteins were colocalized in goblet cells lining the airways of patients with chronic lung diseases. Deletion of the mouse Spdef gene resulted in the absence of goblet cells in tracheal/laryngeal submucosal glands and in the conducting airway epithelium after pulmonary allergen exposure in vivo. These data show that SPDEF plays a critical role in regulating a transcriptional network mediating the goblet cell differentiation and mucus hyperproduction associated with chronic pulmonary disorders.

  4. TCR Signal Strength Regulates Akt Substrate Specificity To Induce Alternate Murine Th and T Regulatory Cell Differentiation Programs.

    Science.gov (United States)

    Hawse, William F; Boggess, William C; Morel, Penelope A

    2017-07-15

    The Akt/mTOR pathway is a key driver of murine CD4 + T cell differentiation, and induction of regulatory T (Treg) cells results from low TCR signal strength and low Akt/mTOR signaling. However, strong TCR signals induce high Akt activity that promotes Th cell induction. Yet, it is unclear how Akt controls alternate T cell fate decisions. We find that the strength of the TCR signal results in differential Akt enzymatic activity. Surprisingly, the Akt substrate networks associated with T cell fate decisions are qualitatively different. Proteomic profiling of Akt signaling networks during Treg versus Th induction demonstrates that Akt differentially regulates RNA processing and splicing factors to drive T cell differentiation. Interestingly, heterogeneous nuclear ribonucleoprotein (hnRNP) L or hnRNP A1 are Akt substrates during Treg induction and have known roles in regulating the stability and splicing of key mRNAs that code for proteins in the canonical TCR signaling pathway, including CD3ζ and CD45. Functionally, inhibition of Akt enzymatic activity results in the dysregulation of splicing during T cell differentiation, and knockdown of hnRNP L or hnRNP A1 results in the lower induction of Treg cells. Together, this work suggests that a switch in substrate specificity coupled to the phosphorylation status of Akt may lead to alternative cell fates and demonstrates that proteins involved with alternative splicing are important factors in T cell fate decisions. Copyright © 2017 by The American Association of Immunologists, Inc.

  5. Regulation and patterns of endogenous and exogenous gene expression during differentiation of embryonal carcinoma cells

    International Nuclear Information System (INIS)

    Astigiano, S.; Sherman, M.I.; Abarzua, P.

    1989-01-01

    Embryonal carcinoma (EC) cells offer an interesting model system for evaluating differentiation because the cells are pluripotent, thus resembling germ cells and embryonic stem cells, and because a number of agents have been defined that are capable of promoting the differentiation of these cells. This chapter examines how EC cells might be triggered to differentiate, with emphasis on retinoic acid because this compound is a potent, naturally occurring inducer that has been studied extensively in this system. The nature of alterations in gene expression during EC cell differentiation is reviewed from the perspective of evaluating whether these changes are likely to be responsible for, or a result of, the differentiation event. Finally, the authors consider in molecular terms why EC cells, but not their differentiated derivatives, are refractory to the expression of many viral genomes following infection. Based upon these studies, they propose that fundamental changes in gene expression that are observed when differentiation is triggered in EC cells are likely to be due to the disappearance or neutralization of strong repressor elements

  6. The Satellite Cell Niche Regulates the Balance between Myoblast Differentiation and Self-Renewal via p53.

    Science.gov (United States)

    Flamini, Valentina; Ghadiali, Rachel S; Antczak, Philipp; Rothwell, Amy; Turnbull, Jeremy E; Pisconti, Addolorata

    2018-03-13

    Satellite cells are adult muscle stem cells residing in a specialized niche that regulates their homeostasis. How niche-generated signals integrate to regulate gene expression in satellite cell-derived myoblasts is poorly understood. We undertook an unbiased approach to study the effect of the satellite cell niche on satellite cell-derived myoblast transcriptional regulation and identified the tumor suppressor p53 as a key player in the regulation of myoblast quiescence. After activation and proliferation, a subpopulation of myoblasts cultured in the presence of the niche upregulates p53 and fails to differentiate. When satellite cell self-renewal is modeled ex vivo in a reserve cell assay, myoblasts treated with Nutlin-3, which increases p53 levels in the cell, fail to differentiate and instead become quiescent. Since both these Nutlin-3 effects are rescued by small interfering RNA-mediated p53 knockdown, we conclude that a tight control of p53 levels in myoblasts regulates the balance between differentiation and return to quiescence. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

  7. Somatic stem cell differentiation is regulated by PI3K/Tor signaling in response to local cues.

    Science.gov (United States)

    Amoyel, Marc; Hillion, Kenzo-Hugo; Margolis, Shally R; Bach, Erika A

    2016-11-01

    Stem cells reside in niches that provide signals to maintain self-renewal, and differentiation is viewed as a passive process that depends on loss of access to these signals. Here, we demonstrate that the differentiation of somatic cyst stem cells (CySCs) in the Drosophila testis is actively promoted by PI3K/Tor signaling, as CySCs lacking PI3K/Tor activity cannot differentiate properly. We find that an insulin peptide produced by somatic cells immediately outside of the stem cell niche acts locally to promote somatic differentiation through Insulin-like receptor (InR) activation. These results indicate that there is a local 'differentiation' niche that upregulates PI3K/Tor signaling in the early daughters of CySCs. Finally, we demonstrate that CySCs secrete the Dilp-binding protein ImpL2, the Drosophila homolog of IGFBP7, into the stem cell niche, which blocks InR activation in CySCs. Thus, we show that somatic cell differentiation is controlled by PI3K/Tor signaling downstream of InR and that the local production of positive and negative InR signals regulates the differentiation niche. These results support a model in which leaving the stem cell niche and initiating differentiation are actively induced by signaling. © 2016. Published by The Company of Biologists Ltd.

  8. Substrate stiffness and oxygen as regulators of stem cell differentiation during skeletal tissue regeneration: a mechanobiological model.

    Directory of Open Access Journals (Sweden)

    Darren Paul Burke

    Full Text Available Extrinsic mechanical signals have been implicated as key regulators of mesenchymal stem cell (MSC differentiation. It has been possible to test different hypotheses for mechano-regulated MSC differentiation by attempting to simulate regenerative events such as bone fracture repair, where repeatable spatial and temporal patterns of tissue differentiation occur. More recently, in vitro studies have identified other environmental cues such as substrate stiffness and oxygen tension as key regulators of MSC differentiation; however it remains unclear if and how such cues determine stem cell fate in vivo. As part of this study, a computational model was developed to test the hypothesis that substrate stiffness and oxygen tension regulate stem cell differentiation during fracture healing. Rather than assuming mechanical signals act directly on stem cells to determine their differentiation pathway, it is postulated that they act indirectly to regulate angiogenesis and hence partially determine the local oxygen environment within a regenerating tissue. Chondrogenesis of MSCs was hypothesized to occur in low oxygen regions, while in well vascularised regions of the regenerating tissue a soft local substrate was hypothesised to facilitate adipogenesis while a stiff substrate facilitated osteogenesis. Predictions from the model were compared to both experimental data and to predictions of a well established computational mechanobiological model where tissue differentiation is assumed to be regulated directly by the local mechanical environment. The model predicted all the major events of fracture repair, including cartilaginous bridging, endosteal and periosteal bony bridging and bone remodelling. It therefore provides support for the hypothesis that substrate stiffness and oxygen play a key role in regulating MSC fate during regenerative events such as fracture healing.

  9. Roles of Retinoids and Retinoic Acid Receptors in the Regulation of Hematopoietic Stem Cell Self-Renewal and Differentiation

    Directory of Open Access Journals (Sweden)

    Louise E. Purton

    2007-01-01

    Full Text Available Multipotent hematopoietic stem cells (HSCs sustain blood cell production throughout an individual's lifespan through complex processes ultimately leading to fates of self-renewal, differentiation or cell death decisions. A fine balance between these decisions in vivo allows for the size of the HSC pool to be maintained. While many key factors involved in regulating HSC/progenitor cell differentiation and cell death are known, the critical regulators of HSC self-renewal are largely unknown. In recent years, however, a number of studies describing methods of increasing or decreasing the numbers of HSCs in a given population have emerged. Of major interest here are the emerging roles of retinoids in the regulation of HSCs.

  10. Hypoxia is a key regulator of limbal epithelial stem cell growth and differentiation

    DEFF Research Database (Denmark)

    Bath, Chris; Yang, Sufang; Muttuvelu, Danson

    2013-01-01

    The aim of this study was to determine whether the growth and differentiation of limbal epithelial stem cell cultures could be controlled through manipulation of the oxygen tension. Limbal epithelial cells were isolated from corneoscleral disks, and cultured using either feeder cells in a growth......, progression through cell cycle, colony forming efficiency (CFE), and expression of stem cell (ABCG2 and p63α) and differentiation (CK3) markers was determined throughout the culture period of up to 18 days. Low oxygen levels favored a stem cell phenotype with a lower proliferative rate, high CFE......, and a relatively higher expression of ABCG2 and p63α, while higher levels of oxygen led not only to decreased CFE but also to increased proportion of differentiated cells positive for CK3. Hypoxic cultures may thus potentially improve stem cell grafts for cultured limbal epithelial transplantation (CLET)....

  11. PPARγ and MyoD are differentially regulated by myostatin in adipose-derived stem cells and muscle satellite cells

    International Nuclear Information System (INIS)

    Zhang, Feng; Deng, Bing; Wen, Jianghui; Chen, Kun; Liu, Wu; Ye, Shengqiang; Huang, Haijun; Jiang, Siwen; Xiong, Yuanzhu

    2015-01-01

    Myostatin (MSTN) is a secreted protein belonging to the transforming growth factor-β (TGF-β) family that is primarily expressed in skeletal muscle and also functions in adipocyte maturation. Studies have shown that MSTN can inhibit adipogenesis in muscle satellite cells (MSCs) but not in adipose-derived stem cells (ADSCs). However, the mechanism by which MSTN differently regulates adipogenesis in these two cell types remains unknown. Peroxisome proliferator-activated receptor-γ (PPARγ) and myogenic differentiation factor (MyoD) are two key transcription factors in fat and muscle cell development that influence adipogenesis. To investigate whether MSTN differentially regulates PPARγ and MyoD, we analyzed PPARγ and MyoD expression by assessing mRNA, protein and methylation levels in ADSCs and MSCs after treatment with 100 ng/mL MSTN for 0, 24, and 48 h. PPARγ mRNA levels were downregulated after 24 h and upregulated after 48 h of treatment in ADSCs, whereas in MSCs, PPARγ levels were downregulated at both time points. MyoD expression was significantly increased in ADSCs and decreased in MSCs. PPARγ and MyoD protein levels were upregulated in ADSCs and downregulated in MSCs. The CpG methylation levels of the PPARγ and MyoD promoters were decreased in ADSCs and increased in MSCs. Therefore, this study demonstrated that the different regulatory adipogenic roles of MSTN in ADSCs and MSCs act by differentially regulating PPARγ and MyoD expression. - Highlights: • PPARγ and MyoD mRNA and protein levels are upregulated by myostatin in ADSCs. • PPARγ and MyoD mRNA and protein levels are downregulated by myostatin in MSCs. • PPARγ exhibited different methylation levels in myostatin-treated ADSCs and MSCs. • MyoD exhibited different methylation levels in myostatin-treated ADSCs and MSCs. • PPARγ and MyoD are differentially regulated by myostatin in ADSCs and MSCs

  12. PPARγ and MyoD are differentially regulated by myostatin in adipose-derived stem cells and muscle satellite cells

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Feng [Key Laboratory of Swine Genetics and Breeding of the Agricultural Ministry and Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of the Ministry of Education, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan, 430070 (China); Deng, Bing [Wuhan Institute of Animal Science and Veterinary Medicine, Wuhan Academy of Agricultural Science and Technology, Wuhan, Hubei, 430208 (China); Wen, Jianghui [Wu Han University of Technology, Wuhan 430074 (China); Chen, Kun [Key Laboratory of Swine Genetics and Breeding of the Agricultural Ministry and Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of the Ministry of Education, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan, 430070 (China); Liu, Wu; Ye, Shengqiang; Huang, Haijun [Wuhan Institute of Animal Science and Veterinary Medicine, Wuhan Academy of Agricultural Science and Technology, Wuhan, Hubei, 430208 (China); Jiang, Siwen, E-mail: jiangsiwen@mail.hzau.edu.cn [Key Laboratory of Swine Genetics and Breeding of the Agricultural Ministry and Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of the Ministry of Education, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan, 430070 (China); Xiong, Yuanzhu, E-mail: xiongyzhu@163.com [Key Laboratory of Swine Genetics and Breeding of the Agricultural Ministry and Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of the Ministry of Education, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan, 430070 (China)

    2015-03-06

    Myostatin (MSTN) is a secreted protein belonging to the transforming growth factor-β (TGF-β) family that is primarily expressed in skeletal muscle and also functions in adipocyte maturation. Studies have shown that MSTN can inhibit adipogenesis in muscle satellite cells (MSCs) but not in adipose-derived stem cells (ADSCs). However, the mechanism by which MSTN differently regulates adipogenesis in these two cell types remains unknown. Peroxisome proliferator-activated receptor-γ (PPARγ) and myogenic differentiation factor (MyoD) are two key transcription factors in fat and muscle cell development that influence adipogenesis. To investigate whether MSTN differentially regulates PPARγ and MyoD, we analyzed PPARγ and MyoD expression by assessing mRNA, protein and methylation levels in ADSCs and MSCs after treatment with 100 ng/mL MSTN for 0, 24, and 48 h. PPARγ mRNA levels were downregulated after 24 h and upregulated after 48 h of treatment in ADSCs, whereas in MSCs, PPARγ levels were downregulated at both time points. MyoD expression was significantly increased in ADSCs and decreased in MSCs. PPARγ and MyoD protein levels were upregulated in ADSCs and downregulated in MSCs. The CpG methylation levels of the PPARγ and MyoD promoters were decreased in ADSCs and increased in MSCs. Therefore, this study demonstrated that the different regulatory adipogenic roles of MSTN in ADSCs and MSCs act by differentially regulating PPARγ and MyoD expression. - Highlights: • PPARγ and MyoD mRNA and protein levels are upregulated by myostatin in ADSCs. • PPARγ and MyoD mRNA and protein levels are downregulated by myostatin in MSCs. • PPARγ exhibited different methylation levels in myostatin-treated ADSCs and MSCs. • MyoD exhibited different methylation levels in myostatin-treated ADSCs and MSCs. • PPARγ and MyoD are differentially regulated by myostatin in ADSCs and MSCs.

  13. SHP1 Regulates Bone Mass by Directing Mesenchymal Stem Cell Differentiation

    Directory of Open Access Journals (Sweden)

    Menghui Jiang

    2016-07-01

    Full Text Available Osteoblasts and adipocytes are derived from a common precursor, mesenchymal stem cells (MSCs. Alterations in the normal fate of differentiating MSCs are involved in the development of obesity and osteoporosis. Here, we report that viable motheaten (mev mice, which are deficient in the SH2-domain-containing phosphatase-1 (SHP1, develop osteoporosis spontaneously. Consistently, MSCs from mev/mev mice exhibit significantly reduced osteogenic potential and greatly increased adipogenic potential. When MSCs were transplanted into nude mice, SHP1-deficient MSCs resulted in diminished bone formation compared with wild-type MSCs. SHP1 was found to bind to GSK3β and suppress its kinase activity by dephosphorylating pY216, thus resulting in β-catenin stabilization. Mice, in which SHP1 was deleted in MSCs using SHP1fl/flDermo1-cre, displayed significantly decreased bone mass and increased adipose tissue. Taken together, these results suggest a possible role for SHP1 in controlling tissue homeostasis through modulation of MSC differentiation via Wnt signaling regulation.

  14. CUDC-907 Promotes Bone Marrow Adipocytic Differentiation Through Inhibition of Histone Deacetylase and Regulation of Cell Cycle.

    Science.gov (United States)

    Ali, Dalia; Alshammari, Hassan; Vishnubalaji, Radhakrishnan; Chalisserry, Elna Paul; Hamam, Rimi; Alfayez, Musaad; Kassem, Moustapha; Aldahmash, Abdullah; Alajez, Nehad M

    2017-03-01

    The role of bone marrow adipocytes (BMAs) in overall energy metabolism and their effects on bone mass are currently areas of intensive investigation. BMAs differentiate from bone marrow stromal cells (BMSCs); however, the molecular mechanisms regulating BMA differentiation are not fully understood. In this study, we investigated the effect of CUDC-907, identified by screening an epigenetic small-molecule library, on adipocytic differentiation of human BMSCs (hBMSCs) and determined its molecular mechanism of action. Human bone marrow stromal cells exposed to CUDC-907 (500 nM) exhibited enhanced adipocytic differentiation (∼2.9-fold increase, P < 0.005) compared with that of control cells. Global gene expression and signaling pathway analyses of differentially expressed genes revealed a strong enrichment of genes involved in adipogenesis, cell cycle, and DNA replication. Chromatin immune precipitation combined with quantitative polymerase chain reaction showed significant increase in H3K9ac epigenetic marker in the promoter regions of AdipoQ, FABP4, PPARγ, KLF15, and CEBPA in CUDC-907-treated hBMSCs. Follow-up experiments corroborated that the inhibition of histone deacetylase (HDAC) activity enhanced adipocytic differentiation, while the inhibition of PI3K decreased adipocytic differentiation. In addition, CUDC-907 arrested hBMSCs in the G0-G1 phase of the cell cycle and reduced the number of S-phase cells. Our data reveal that HDAC, PI3K, and cell cycle genes are important regulators of BMA formation and demonstrate that adipocyte differentiation of hBMSCs is associated with complex changes in a number of epigenetic and genetic pathways, which can be targeted to regulate BMA formation.

  15. HDAC1 and HDAC2 restrain the intestinal inflammatory response by regulating intestinal epithelial cell differentiation.

    Directory of Open Access Journals (Sweden)

    Naomie Turgeon

    . Thus, epithelial HDAC1 and HDAC2 restrain the intestinal inflammatory response, by regulating intestinal epithelial cell proliferation and differentiation.

  16. Differential response of cell-cycle and cell-expansion regulators to heat stress in apple (Malus domestica) fruitlets.

    Science.gov (United States)

    Flaishman, Moshe A; Peles, Yuval; Dahan, Yardena; Milo-Cochavi, Shira; Frieman, Aviad; Naor, Amos

    2015-04-01

    Temperature is one of the most significant factors affecting physiological and biochemical aspects of fruit development. Current and progressing global warming is expected to change climate in the traditional deciduous fruit tree cultivation regions. In this study, 'Golden Delicious' trees, grown in a controlled environment or commercial orchard, were exposed to different periods of heat treatment. Early fruitlet development was documented by evaluating cell number, cell size and fruit diameter for 5-70 days after full bloom. Normal activities of molecular developmental and growth processes in apple fruitlets were disrupted under daytime air temperatures of 29°C and higher as a result of significant temporary declines in cell-production and cell-expansion rates, respectively. Expression screening of selected cell cycle and cell expansion genes revealed the influence of high temperature on genetic regulation of apple fruitlet development. Several core cell-cycle and cell-expansion genes were differentially expressed under high temperatures. While expression levels of B-type cyclin-dependent kinases and A- and B-type cyclins declined moderately in response to elevated temperatures, expression of several cell-cycle inhibitors, such as Mdwee1, Mdrbr and Mdkrps was sharply enhanced as the temperature rose, blocking the cell-cycle cascade at the G1/S and G2/M transition points. Moreover, expression of several expansin genes was associated with high temperatures, making them potentially useful as molecular platforms to enhance cell-expansion processes under high-temperature regimes. Understanding the molecular mechanisms of heat tolerance associated with genes controlling cell cycle and cell expansion may lead to the development of novel strategies for improving apple fruit productivity under global warming. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  17. The homeobox gene Hex regulates hepatocyte differentiation from embryonic stem cell-derived endoderm.

    Science.gov (United States)

    Kubo, Atsushi; Kim, Yon Hui; Irion, Stefan; Kasuda, Shogo; Takeuchi, Mitsuaki; Ohashi, Kazuo; Iwano, Masayuki; Dohi, Yoshiko; Saito, Yoshihiko; Snodgrass, Ralph; Keller, Gordon

    2010-02-01

    We investigated the role of the hematopoietically expressed homeobox (Hex) in the differentiation and development of hepatocytes within embryonic stem cell (ESC)-derived embryoid bodies (EBs). Analyses of hepatic endoderm derived from Hex(-/-) EBs revealed a dramatic reduction in the levels of albumin (Alb) and alpha-fetoprotein (Afp) expression. In contrast, stage-specific forced expression of Hex in EBs from wild-type ESCs led to the up-regulation of Alb and Afp expression and secretion of Alb and transferrin. These inductive effects were restricted to c-kit(+) endoderm-enriched EB-derived populations, suggesting that Hex functions at the level of hepatic specification of endoderm in this model. Microarray analysis revealed that Hex regulated the expression of a broad spectrum of hepatocyte-related genes, including fibrinogens, apolipoproteins, and cytochromes. When added to the endoderm-induced EBs, bone morphogenetic protein 4 acted synergistically with Hex in the induction of expression of Alb, Afp, carbamoyl phosphate synthetase, transcription factor 1, and CCAAT/enhancer binding protein alpha. These findings indicate that Hex plays a pivotal role during induction of liver development from endoderm in this in vitro model and suggest that this strategy may provide important insight into the generation of functional hepatocytes from ESCs.

  18. Inhibition of Rho kinase regulates specification of early differentiation events in P19 embryonal carcinoma stem cells.

    Directory of Open Access Journals (Sweden)

    Roman J Krawetz

    Full Text Available The Rho kinase pathway plays a key role in many early cell/tissue determination events that take place in embryogenesis. Rho and its downstream effector Rho kinase (ROCK play pivotal roles in cell migration, apoptosis (membrane blebbing, cell proliferation/cell cycle, cell-cell adhesion and gene regulation. We and others have previously demonstrated that inhibition of ROCK blocks endoderm differentiation in embryonal carcinoma stem cells, however, the effect of ROCK inhibition on mesoderm and ectoderm specification has not been fully examined. In this study, the role of ROCK within the specification and differentiation of all three germ layers was examined.P19 cells were treated with the specific ROCK inhibitor Y-27623, and increase in differentiation efficiency into neuro-ectodermal and mesodermal lineages was observed. However, as expected a dramatic decrease in early endodermal markers was observed when ROCK was inhibited. Interestingly, within these ROCK-inhibited RA treated cultures, increased levels of mesodermal or ectodermal markers were not observed, instead it was found that the pluripotent markers SSEA-1 and Oct-4 remained up-regulated similar to that seen in undifferentiated cultures. Using standard and widely accepted methods for reproducible P19 differentiation into all three germ layers, an enhancement of mesoderm and ectoderm differentiation with a concurrent loss of endoderm lineage specification was observed with Y-27632 treatment. Evidence would suggest that this effect is in part mediated through TGF-β and SMAD signaling as ROCK-inhibited cells displayed aberrant SMAD activation and did not return to a 'ground' state after the inhibition had been removed.Given this data and the fact that only a partial rescue of normal differentiation capacity occurred when ROCK inhibition was alleviated, the effect of ROCK inhibition on the differentiation capacity of pluripotent cell populations should be further examined to elucidate the

  19. Calcium-containing scaffolds induce bone regeneration by regulating mesenchymal stem cell differentiation and migration.

    Science.gov (United States)

    Aquino-Martínez, Rubén; Angelo, Alcira P; Pujol, Francesc Ventura

    2017-11-16

    Osteoinduction and subsequent bone formation rely on efficient mesenchymal stem cell (MSC) recruitment. It is also known that migration is induced by gradients of growth factors and cytokines. Degradation of Ca 2+ -containing biomaterials mimics the bone remodeling compartment producing a localized calcium-rich osteoinductive microenvironment. The aim of our study was to determine the effect of calcium sulfate (CaSO 4 ) on MSC migration. In addition, to evaluate the influence of CaSO 4 on MSC differentiation and the potential molecular mechanisms involved. A circular calvarial bone defect (5 mm diameter) was created in the parietal bone of 35 Balb-C mice. We prepared and implanted a cell-free agarose/gelatin scaffold alone or in combination with different CaSO 4 concentrations into the bone defects. After 7 weeks, we determined the new bone regenerated by micro-CT and histological analysis. In vitro, we evaluated the CaSO 4 effects on MSC migration by both wound healing and agarose spot assays. Osteoblastic gene expression after BMP-2 and CaSO 4 treatment was also evaluated by qPCR. CaSO 4 increased MSC migration and bone formation in a concentration-dependent manner. Micro-CT analysis showed that the addition of CaSO 4 significantly enhanced bone regeneration compared to the scaffold alone. The histological evaluation confirmed an increased number of endogenous cells recruited into the cell-free CaSO 4 -containing scaffolds. Furthermore, MSC migration in vitro and active AKT levels were attenuated when CaSO 4 and BMP-2 were in combination. Addition of LY294002 and Wortmannin abrogated the CaSO 4 effects on MSC migration. Specific CaSO 4 concentrations induce bone regeneration of calvarial defects in part by acting on the host's undifferentiated MSCs and promoting their migration. Progenitor cell recruitment is followed by a gradual increment in osteoblast gene expression. Moreover, CaSO 4 regulates BMP-2-induced MSC migration by differentially activating the PI3

  20. Calcium-containing scaffolds induce bone regeneration by regulating mesenchymal stem cell differentiation and migration

    Directory of Open Access Journals (Sweden)

    Rubén Aquino-Martínez

    2017-11-01

    Full Text Available Abstract Background Osteoinduction and subsequent bone formation rely on efficient mesenchymal stem cell (MSC recruitment. It is also known that migration is induced by gradients of growth factors and cytokines. Degradation of Ca2+-containing biomaterials mimics the bone remodeling compartment producing a localized calcium-rich osteoinductive microenvironment. The aim of our study was to determine the effect of calcium sulfate (CaSO4 on MSC migration. In addition, to evaluate the influence of CaSO4 on MSC differentiation and the potential molecular mechanisms involved. Methods A circular calvarial bone defect (5 mm diameter was created in the parietal bone of 35 Balb-C mice. We prepared and implanted a cell-free agarose/gelatin scaffold alone or in combination with different CaSO4 concentrations into the bone defects. After 7 weeks, we determined the new bone regenerated by micro-CT and histological analysis. In vitro, we evaluated the CaSO4 effects on MSC migration by both wound healing and agarose spot assays. Osteoblastic gene expression after BMP-2 and CaSO4 treatment was also evaluated by qPCR. Results CaSO4 increased MSC migration and bone formation in a concentration-dependent manner. Micro-CT analysis showed that the addition of CaSO4 significantly enhanced bone regeneration compared to the scaffold alone. The histological evaluation confirmed an increased number of endogenous cells recruited into the cell-free CaSO4-containing scaffolds. Furthermore, MSC migration in vitro and active AKT levels were attenuated when CaSO4 and BMP-2 were in combination. Addition of LY294002 and Wortmannin abrogated the CaSO4 effects on MSC migration. Conclusions Specific CaSO4 concentrations induce bone regeneration of calvarial defects in part by acting on the host’s undifferentiated MSCs and promoting their migration. Progenitor cell recruitment is followed by a gradual increment in osteoblast gene expression. Moreover, CaSO4 regulates BMP-2-induced

  1. The transcription factor Th-POK negatively regulates Th17 differentiation in Vα14i NKT cells

    Science.gov (United States)

    Engel, Isaac; Zhao, Meng; Kappes, Dietmar; Taniuchi, Ichiro

    2012-01-01

    The majority of mouse Vα14 invariant natural killer T (Vα14i NKT) cells produce several cytokines, including IFNγ and IL-4, very rapidly after activation. A subset of these cells, known as NKT17 cells, however, differentiates in the thymus to preferentially produce IL-17. Here, we show that the transcription factor—known as T helper, Poxviruses, and Zinc-finger and Krüppel family, (Th-POK)—represses the formation of NKT17 cells. Vα14i NKT cells from Th-POK–mutant helper deficient (hd/hd) mice have increased transcripts of genes normally expressed by Th17 and NKT17 cells, and even heterozygosity for this mutation leads to dramatically increased numbers of Vα14i NKT cells that are poised to express IL-17, especially in the thymus and lymph nodes. In addition, using gene reporter mice, we demonstrate that NKT17 cells from wild-type mice express lower amounts of Th-POK than the majority population of Vα14i NKT cells. We also show that retroviral transduction of Th-POK represses the expression of the Th17 master regulator RORγT in Vα14i NKT-cell lines. Our data suggest that NKT17-cell differentiation is intrinsically regulated by Th-POK activity, with only low levels of Th-POK permissive for the differentiation of NKT17 cells. PMID:23034280

  2. Keratin 5/14‑mediated cell differentiation and transformation are regulated by TAp63 and Notch‑1 in oral squamous cell carcinoma‑derived cells.

    Science.gov (United States)

    Srivastava, Saumya S; Alam, Hunain; Patil, Sonam J; Shrinivasan, Rashmi; Raikundalia, Sweta; Chaudhari, Pratik Rajeev; Vaidya, Milind M

    2018-05-01

    Keratins 5/14 (K5/14) are intermediate filament proteins expressed in the basal layer of stratified epithelial cells and are known targets of p63. Previous research in our laboratory showed that upon K5/14 downregulation in oral squamous cell carcinoma (OSCC)‑derived cells, there was an increase in intracellular Notch‑1 levels and differentiation markers such as involucrin, keratin 1 and a decrease in tumorigenic potential in vivo. However, the molecules involved in the K14 regulated cell differentiation and transformation are not known to date. In order to understand the possible role of TAp63, we downregulated TAp63 in a K14‑knockdown background. We observed that there was a decrease in the expression of Notch‑1. Expression levels of differentiation markers such as involucrin, K1, loricrin and filaggrin were also decreased. Furthermore, TAp63 downregulation led to an increase in invasion, migration and in vivo tumorigenic potential of these cells. We observed a decrease in β‑catenin signaling in K14‑downregulated cells. Notably, when TAp63 was downregulated in K14‑knockdown cells, there was increase in non‑phospho β‑catenin levels. Hence, this study indicates that TAp63 plays an important role in K14‑downregulated cells possibly by regulating the Notch‑1 expression. K14 regulates the expression of TAp63 which in turn regulates expression of Notch‑1. The present study is a step forward in our quest to understand the functional significance of molecules that regulate the process of differentiation and tumorigenesis in stratified epithelial cells.

  3. Identification of key factors regulating self-renewal and differentiation in EML hematopoietic precursor cells by RNA-sequencing analysis.

    Science.gov (United States)

    Zong, Shan; Deng, Shuyun; Chen, Kenian; Wu, Jia Qian

    2014-11-11

    Hematopoietic stem cells (HSCs) are used clinically for transplantation treatment to rebuild a patient's hematopoietic system in many diseases such as leukemia and lymphoma. Elucidating the mechanisms controlling HSCs self-renewal and differentiation is important for application of HSCs for research and clinical uses. However, it is not possible to obtain large quantity of HSCs due to their inability to proliferate in vitro. To overcome this hurdle, we used a mouse bone marrow derived cell line, the EML (Erythroid, Myeloid, and Lymphocytic) cell line, as a model system for this study. RNA-sequencing (RNA-Seq) has been increasingly used to replace microarray for gene expression studies. We report here a detailed method of using RNA-Seq technology to investigate the potential key factors in regulation of EML cell self-renewal and differentiation. The protocol provided in this paper is divided into three parts. The first part explains how to culture EML cells and separate Lin-CD34+ and Lin-CD34- cells. The second part of the protocol offers detailed procedures for total RNA preparation and the subsequent library construction for high-throughput sequencing. The last part describes the method for RNA-Seq data analysis and explains how to use the data to identify differentially expressed transcription factors between Lin-CD34+ and Lin-CD34- cells. The most significantly differentially expressed transcription factors were identified to be the potential key regulators controlling EML cell self-renewal and differentiation. In the discussion section of this paper, we highlight the key steps for successful performance of this experiment. In summary, this paper offers a method of using RNA-Seq technology to identify potential regulators of self-renewal and differentiation in EML cells. The key factors identified are subjected to downstream functional analysis in vitro and in vivo.

  4. Differential L1 regulation in pluripotent stem cells of humans and apes.

    Science.gov (United States)

    Marchetto, Maria C N; Narvaiza, Iñigo; Denli, Ahmet M; Benner, Christopher; Lazzarini, Thomas A; Nathanson, Jason L; Paquola, Apuã C M; Desai, Keval N; Herai, Roberto H; Weitzman, Matthew D; Yeo, Gene W; Muotri, Alysson R; Gage, Fred H

    2013-11-28

    Identifying cellular and molecular differences between human and non-human primates (NHPs) is essential to the basic understanding of the evolution and diversity of our own species. Until now, preserved tissues have been the main source for most comparative studies between humans, chimpanzees (Pan troglodytes) and bonobos (Pan paniscus). However, these tissue samples do not fairly represent the distinctive traits of live cell behaviour and are not amenable to genetic manipulation. We propose that induced pluripotent stem (iPS) cells could be a unique biological resource to determine relevant phenotypical differences between human and NHPs, and that those differences could have potential adaptation and speciation value. Here we describe the generation and initial characterization of iPS cells from chimpanzees and bonobos as new tools to explore factors that may have contributed to great ape evolution. Comparative gene expression analysis of human and NHP iPS cells revealed differences in the regulation of long interspersed element-1 (L1, also known as LINE-1) transposons. A force of change in mammalian evolution, L1 elements are retrotransposons that have remained active during primate evolution. Decreased levels of L1-restricting factors APOBEC3B (also known as A3B) and PIWIL2 (ref. 7) in NHP iPS cells correlated with increased L1 mobility and endogenous L1 messenger RNA levels. Moreover, results from the manipulation of A3B and PIWIL2 levels in iPS cells supported a causal inverse relationship between levels of these proteins and L1 retrotransposition. Finally, we found increased copy numbers of species-specific L1 elements in the genome of chimpanzees compared to humans, supporting the idea that increased L1 mobility in NHPs is not limited to iPS cells in culture and may have also occurred in the germ line or embryonic cells developmentally upstream to germline specification during primate evolution. We propose that differences in L1 mobility may have

  5. Pluripotency factors in embryonic stem cells regulate differentiation into germ layers.

    Science.gov (United States)

    Thomson, Matt; Liu, Siyuan John; Zou, Ling-Nan; Smith, Zack; Meissner, Alexander; Ramanathan, Sharad

    2011-06-10

    Cell fate decisions are fundamental for development, but we do not know how transcriptional networks reorganize during the transition from a pluripotent to a differentiated cell state. Here, we asked how mouse embryonic stem cells (ESCs) leave the pluripotent state and choose between germ layer fates. By analyzing the dynamics of the transcriptional circuit that maintains pluripotency, we found that Oct4 and Sox2, proteins that maintain ESC identity, also orchestrate germ layer fate selection. Oct4 suppresses neural ectodermal differentiation and promotes mesendodermal differentiation; Sox2 inhibits mesendodermal differentiation and promotes neural ectodermal differentiation. Differentiation signals continuously and asymmetrically modulate Oct4 and Sox2 protein levels, altering their binding pattern in the genome, and leading to cell fate choice. The same factors that maintain pluripotency thus also integrate external signals and control lineage selection. Our study provides a framework for understanding how complex transcription factor networks control cell fate decisions in progenitor cells. Copyright © 2011 Elsevier Inc. All rights reserved.

  6. A supramolecular look at microenvironmental regulation of limbal epithelial stem cells and the differentiation of their progeny

    Directory of Open Access Journals (Sweden)

    Marcela Aldrovani

    Full Text Available ABSTRACT Various approaches have been taken to improve our knowledge of the microenvironmental regulation of limbal epithelial stem cells. Researchers have extensively investigated the roles of growth factors, survival factors, cytokines, enzymes, and permeable molecules secreted by the limbal cells. However, recent evidence suggests that stem cell fate (i.e., self-renewal or differentiation can also be influenced by biophysical and mechanical cues related to the supramolecular organization and the liquid crystalline (mesophase nature of the stromal extracellular matrix. These cues can be sensed by stem cells and transduced into intracellular biochemical and functional responses, a process known as mechanotransduction. The objective of this review is to offer perspectives on the supramolecular microenvironmental regulation of limbal epithelial stem cells and the differentiation of their progeny.

  7. microRNA-320/RUNX2 axis regulates adipocytic differentiation of human mesenchymal (skeletal) stem cells

    DEFF Research Database (Denmark)

    Hamam, D; Ali, D; Vishnubalaji, R

    2014-01-01

    The molecular mechanisms promoting lineage-specific commitment of human mesenchymal (skeletal or stromal) stem cells (hMSCs) into adipocytes (ADs) are not fully understood. Thus, we performed global microRNA (miRNA) and gene expression profiling during adipocytic differentiation of h...... differentiation and accelerated formation of mature ADs in ex vivo cultures. Integrated analysis of bioinformatics and global gene expression profiling in miR-320c overexpressing cells and during adipocytic differentiation of hMSC identified several biologically relevant gene targets for miR-320c including RUNX2...

  8. Glimpse into Hox and tale regulation of cell differentiation and reprogramming.

    Science.gov (United States)

    Cerdá-Esteban, Nuria; Spagnoli, Francesca M

    2014-01-01

    During embryonic development, cells become gradually restricted in their developmental potential and start elaborating lineage-specific transcriptional networks to ultimately acquire a unique differentiated state. Hox genes play a central role in specifying regional identities, thereby providing the cell with critical information on positional value along its differentiation path. The exquisite DNA-binding specificity of the Hox proteins is frequently dependent upon their interaction with members of the TALE family of homeodomain proteins. In addition to their function as Hox-cofactors, TALE homeoproteins control multiple crucial developmental processes through Hox-independent mechanisms. Here, we will review recent findings on the function of both Hox and TALE proteins in cell differentiation, referring mostly to vertebrate species. In addition, we will discuss the direct implications of this knowledge on cell plasticity and cell reprogramming. Copyright © 2013 Wiley Periodicals, Inc.

  9. Single Low-Dose Radiation Induced Regulation of Keratinocyte Differentiation in Calcium-Induced HaCaT Cells

    Science.gov (United States)

    Hahn, Hyung Jin; Youn, Hae Jeong; Cha, Hwa Jun; Kim, Karam; An, Sungkwan

    2016-01-01

    Background We are continually exposed to low-dose radiation (LDR) in the range 0.1 Gy from natural sources, medical devices, nuclear energy plants, and other industrial sources of ionizing radiation. There are three models for the biological mechanism of LDR: the linear no-threshold model, the hormetic model, and the threshold model. Objective We used keratinocytes as a model system to investigate the molecular genetic effects of LDR on epidermal cell differentiation. Methods To identify keratinocyte differentiation, we performed western blots using a specific antibody for involucrin, which is a precursor protein of the keratinocyte cornified envelope and a marker for keratinocyte terminal differentiation. We also performed quantitative polymerase chain reaction. We examined whether LDR induces changes in involucrin messenger RNA (mRNA) and protein levels in calcium-induced keratinocyte differentiation. Results Exposure of HaCaT cells to LDR (0.1 Gy) induced p21 expression. p21 is a key regulator that induces growth arrest and represses stemness, which accelerates keratinocyte differentiation. We correlated involucrin expression with keratinocyte differentiation, and examined the effects of LDR on involucrin levels and keratinocyte development. LDR significantly increased involucrin mRNA and protein levels during calcium-induced keratinocyte differentiation. Conclusion These studies provide new evidence for the biological role of LDR, and identify the potential to utilize LDR to regulate or induce keratinocyte differentiation. PMID:27489424

  10. Sex-lethal enables germline stem cell differentiation by down-regulating Nanos protein levels during Drosophila oogenesis.

    Science.gov (United States)

    Chau, Johnnie; Kulnane, Laura Shapiro; Salz, Helen K

    2012-06-12

    Drosophila ovarian germ cells require Sex-lethal (Sxl) to exit from the stem cell state and to enter the differentiation pathway. Sxl encodes a female-specific RNA binding protein and in somatic cells serves as the developmental switch gene for somatic sex determination and X-chromosome dosage compensation. None of the known Sxl target genes are required for germline differentiation, leaving open the question of how Sxl promotes the transition from stem cell to committed daughter cell. We address the mechanism by which Sxl regulates this transition through the identification of nanos as one of its target genes. Previous studies have shown that Nanos protein is necessary for GSC self-renewal and is rapidly down-regulated in the daughter cells fated to differentiate in the adult ovary. We find that this dynamic expression pattern is limited to female germ cells and is under Sxl control. In the absence of Sxl, or in male germ cells, Nanos protein is continuously expressed. Furthermore, this female-specific expression pattern is dependent on the presence of canonical Sxl binding sites located in the nanos 3' untranslated region. These results, combined with the observation that nanos RNA associates with the Sxl protein in ovarian extracts and loss and gain of function studies, suggest that Sxl enables the switch from germline stem cell to committed daughter cell by posttranscriptional down-regulation of nanos expression. These findings connect sexual identity to the stem cell self-renewal/differentiation decision and highlight the importance of posttranscriptional gene regulatory networks in controlling stem cell behavior.

  11. The retinoblastoma protein regulates hypoxia-inducible genetic programs, tumor cell invasiveness and neuroendocrine differentiation in prostate cancer cells

    Science.gov (United States)

    Labrecque, Mark P.; Takhar, Mandeep K.; Nason, Rebecca; Santacruz, Stephanie; Tam, Kevin J.; Massah, Shabnam; Haegert, Anne; Bell, Robert H.; Altamirano-Dimas, Manuel; Collins, Colin C.; Lee, Frank J.S.; Prefontaine, Gratien G.; Cox, Michael E.; Beischlag, Timothy V.

    2016-01-01

    Loss of tumor suppressor proteins, such as the retinoblastoma protein (Rb), results in tumor progression and metastasis. Metastasis is facilitated by low oxygen availability within the tumor that is detected by hypoxia inducible factors (HIFs). The HIF1 complex, HIF1α and dimerization partner the aryl hydrocarbon receptor nuclear translocator (ARNT), is the master regulator of the hypoxic response. Previously, we demonstrated that Rb represses the transcriptional response to hypoxia by virtue of its association with HIF1. In this report, we further characterized the role Rb plays in mediating hypoxia-regulated genetic programs by stably ablating Rb expression with retrovirally-introduced short hairpin RNA in LNCaP and 22Rv1 human prostate cancer cells. DNA microarray analysis revealed that loss of Rb in conjunction with hypoxia leads to aberrant expression of hypoxia-regulated genetic programs that increase cell invasion and promote neuroendocrine differentiation. For the first time, we have established a direct link between hypoxic tumor environments, Rb inactivation and progression to late stage metastatic neuroendocrine prostate cancer. Understanding the molecular pathways responsible for progression of benign prostate tumors to metastasized and lethal forms will aid in the development of more effective prostate cancer therapies. PMID:27015368

  12. Allocation of Heme is Differentially Regulated by Ferrochelatase Isoforms in Arabidopsis Cells

    Directory of Open Access Journals (Sweden)

    Nino Asuela Espinas

    2016-08-01

    Full Text Available Heme is involved in various biological processes as a cofactor of hemoproteins located in various organelles. In plant cells, heme is synthesized by two isoforms of plastid-localized ferrochelatase, FC1 and FC2. In this study, by characterizing Arabidopsis T-DNA insertional mutants, we showed that the allocation of heme is differentially regulated by ferrochelatase isoforms in plant cells. Analyses of weak (fc1-1 and null (fc1-2 mutants suggest that FC1-producing heme is required for initial growth of seedling development. In contrast, weak (fc2-1 and null (fc2-2 mutants of FC2 showed pale green leaves and retarded growth, indicating that FC2-producing heme is necessary for chloroplast development. During the initial growth stage, FC2 deficiency caused reduction of plastid cytochromes. In addition, although FC2 deficiency marginally affected the assembly of photosynthetic reaction center complexes, it caused relatively larger but insufficient light-harvesting antenna to reaction centers, resulting in lower efficiency of photosynthesis. In the later vegetative growth, however, fc2-2 recovered photosynthetic growth, showing that FC1-producing heme may complement the FC2 deficiency. On the other hand, reduced level of cytochromes in microsomal fraction was discovered in fc1-1, suggesting that FC1-producing heme is mainly allocated to extraplastidic organelles. Furthermore, the expression of FC1 is induced by the treatment of an elicitor flg22 while that of FC2 was reduced, and fc1-1 abolished the flg22-dependent induction of FC1 expression and peroxidase activity. Consequently, our results clarified that FC2 produces heme for the photosynthetic machinery in the chloroplast, while FC1 is the housekeeping enzyme providing heme cofactor to the entire cell. In addition, FC1 can partly complement FC2 deficiency and is also involved in defense against stressful conditions.

  13. MicroRNA-378 regulates neural stem cell proliferation and differentiation in vitro by modulating Tailless expression.

    Science.gov (United States)

    Huang, Yanxia; Liu, Xiaoguai; Wang, Yaping

    2015-10-16

    Previous studies have suggested that microRNAs (miRNAs) play an important role in regulating neural stem cell (NSC) proliferation and differentiation. However, the precise role of miRNAs in NSC remains largely unexplored. In this study, we showed that miR-378 can target Tailless (TLX), a critical regulator of NSC, to regulate NSC proliferation and differentiation. By bioinformatic algorithms, miR-378 was found to have a predicted target site in the 3'-untranslated region of TLX, which was verified by a dual-luciferase reporter assay. The expression of miR-378 was increased during NSC differentiation and inversely correlated with TLX expression. qPCR and Western blot analysis also showed that miR-378 negatively regulated TLX mRNA and protein expression in neural stem cells (NSCs). Intriguingly, overexpression of miR-378 increased NSC differentiation and reduced NSC proliferation, whereas suppression of miR-378 led to decreased NSC differentiation and increased NSC proliferation. Moreover, the downstream targets of TLX, including p21, PTEN and Wnt/β-catenin were also found to be regulated by miR-378. Additionally, overexpression of TLX rescued the NSC proliferation deficiency induced by miR-378 overexpression and abolished miR-378-promoted NSC differentiation. Taken together, our data suggest that miR-378 is a novel miRNA that regulates NSC proliferation and differentiation via targeting TLX. Therefore, manipulating miR-378 in NSCs could be a novel strategy to develop novel interventions for the treatment of relevant neurological disorders. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. Pluripotency Factors in Embryonic Stem Cells Regulate Differentiation into Germ Layers

    OpenAIRE

    Thomson, Matt; Liu, Siyuan John; Zou, Ling-Nan; Smith, Zack; Meissner, Alexander; Ramanathan, Sharad

    2011-01-01

    Cell fate decisions are fundamental for development, but we do not know how transcriptional networks reorganize during the transition from a pluripotent to a differentiated cell state. Here, we asked how mouse embryonic stem cells (ESCs) leave the pluripotent state and choose between germ layer fates. By analyzing the dynamics of the transcriptional circuit that maintains pluripotency, we found that Oct4 and Sox2, proteins that maintain ESC identity, also orchestrate germ layer fate selection...

  15. Functional dissection of HOXD cluster genes in regulation of neuroblastoma cell proliferation and differentiation.

    Directory of Open Access Journals (Sweden)

    Yunhong Zha

    Full Text Available Retinoic acid (RA can induce growth arrest and neuronal differentiation of neuroblastoma cells and has been used in clinic for treatment of neuroblastoma. It has been reported that RA induces the expression of several HOXD genes in human neuroblastoma cell lines, but their roles in RA action are largely unknown. The HOXD cluster contains nine genes (HOXD1, HOXD3, HOXD4, and HOXD8-13 that are positioned sequentially from 3' to 5', with HOXD1 at the 3' end and HOXD13 the 5' end. Here we show that all HOXD genes are induced by RA in the human neuroblastoma BE(2-C cells, with the genes located at the 3' end being activated generally earlier than those positioned more 5' within the cluster. Individual induction of HOXD8, HOXD9, HOXD10 or HOXD12 is sufficient to induce both growth arrest and neuronal differentiation, which is associated with downregulation of cell cycle-promoting genes and upregulation of neuronal differentiation genes. However, induction of other HOXD genes either has no effect (HOXD1 or has partial effects (HOXD3, HOXD4, HOXD11 and HOXD13 on BE(2-C cell proliferation or differentiation. We further show that knockdown of HOXD8 expression, but not that of HOXD9 expression, significantly inhibits the differentiation-inducing activity of RA. HOXD8 directly activates the transcription of HOXC9, a key effector of RA action in neuroblastoma cells. These findings highlight the distinct functions of HOXD genes in RA induction of neuroblastoma cell differentiation.

  16. ERK2 protein regulates the proliferation of human mesenchymal stem cells without affecting their mobilization and differentiation potential

    International Nuclear Information System (INIS)

    Carcamo-Orive, Ivan; Tejados, Naiara; Delgado, Jesus; Gaztelumendi, Ainhoa; Otaegui, David; Lang, Valerie; Trigueros, Cesar

    2008-01-01

    Human Mesenchymal Stem Cells (hMSC), derived mainly from adult bone marrow, are valuable models for the study of processes involved in stem cell self-renewal and differentiation. As the Extracellular signal-Regulated Kinase (ERK) signalling pathway is a major contributor to cellular growth, differentiation and survival, we have studied the functions of this kinase in hMSC activity. Ablation of ERK2 gene expression (but not ERK1) by RNA interference significantly reduced proliferation of hMSC. This reduction was due to a defect in Cyclin D1 expression and subsequent arrest in the G0/G1 phase of the cell cycle. hMSC growth is enhanced through culture medium supplementation with growth factors (GFs) such as Platelet-Derived Growth Factor (PDGF), basic Fibroblast Growth Factor (bFGF) or Epidermal Growth Factor (EGF). However, these supplements could not rescue the defect observed after ERK2 knockdown, suggesting a common signalling pathway used by these GFs for proliferation. In contrast, ERK1/2 may be dissociated from chemotactic signalling induced by the same GFs. Additionally, hMSCs were capable of differentiating into adipocytes even in the absence of either ERK1 or ERK2 proteins. Our data show that hMSCs do not require cell division to enter the adipogenic differentiation process, indicating that clonal amplification of these cells is not a critical step. However, cell-cell contact seems to be an essential requirement to be able to differentiate into mature adipocytes

  17. Activation of the Extracellular Signal-Regulated Kinase Signaling Is Critical for Human Umbilical Cord Mesenchymal Stem Cell Osteogenic Differentiation

    Directory of Open Access Journals (Sweden)

    Chen-Shuang Li

    2016-01-01

    Full Text Available Human umbilical cord mesenchymal stem cells (hUCMSCs are recognized as candidate progenitor cells for bone regeneration. However, the mechanism of hUCMSC osteogenesis remains unclear. In this study, we revealed that mitogen-activated protein kinases (MAPKs signaling is involved in hUCMSC osteogenic differentiation in vitro. Particularly, the activation of c-Jun N-terminal kinases (JNK and p38 signaling pathways maintained a consistent level in hUCMSCs through the entire 21-day osteogenic differentiation period. At the same time, the activation of extracellular signal-regulated kinases (ERK signaling significantly increased from day 5, peaked at day 9, and declined thereafter. Moreover, gene profiling of osteogenic markers, alkaline phosphatase (ALP activity measurement, and alizarin red staining demonstrated that the application of U0126, a specific inhibitor for ERK activation, completely prohibited hUCMSC osteogenic differentiation. However, when U0126 was removed from the culture at day 9, ERK activation and osteogenic differentiation of hUCMSCs were partially recovered. Together, these findings demonstrate that the activation of ERK signaling is essential for hUCMSC osteogenic differentiation, which points out the significance of ERK signaling pathway to regulate the osteogenic differentiation of hUCMSCs as an alternative cell source for bone tissue engineering.

  18. Auxins differentially regulate root system architecture and cell cycle protein levels in maize seedlings.

    Science.gov (United States)

    Martínez-de la Cruz, Enrique; García-Ramírez, Elpidio; Vázquez-Ramos, Jorge M; Reyes de la Cruz, Homero; López-Bucio, José

    2015-03-15

    Maize (Zea mays) root system architecture has a complex organization, with adventitious and lateral roots determining its overall absorptive capacity. To generate basic information about the earlier stages of root development, we compared the post-embryonic growth of maize seedlings germinated in water-embedded cotton beds with that of plants obtained from embryonic axes cultivated in liquid medium. In addition, the effect of four different auxins, namely indole-3-acetic acid (IAA), 1-naphthaleneacetic acid (NAA), indole-3-butyric acid (IBA) and 2,4-dichlorophenoxyacetic acid (2,4-D) on root architecture and levels of the heat shock protein HSP101 and the cell cycle proteins CKS1, CYCA1 and CDKA1 were analyzed. Our data show that during the first days after germination, maize seedlings develop several root types with a simultaneous and/or continuous growth. The post-embryonic root development started with the formation of the primary root (PR) and seminal scutellar roots (SSR) and then continued with the formation of adventitious crown roots (CR), brace roots (BR) and lateral roots (LR). Auxins affected root architecture in a dose-response fashion; whereas NAA and IBA mostly stimulated crown root formation, 2,4-D showed a strong repressing effect on growth. The levels of HSP101, CKS1, CYCA1 and CDKA in root and leaf tissues were differentially affected by auxins and interestingly, HSP101 registered an auxin-inducible and root specific expression pattern. Taken together, our results show the timing of early branching patterns of maize and indicate that auxins regulate root development likely through modulation of the HSP101 and cell cycle proteins. Copyright © 2014 Elsevier GmbH. All rights reserved.

  19. p120-catenin differentially regulates cell migration by Rho-dependent intracellular and secreted signals

    DEFF Research Database (Denmark)

    Epifano, Carolina; Megias, Diego; Perez-Moreno, Mirna

    2014-01-01

    The adherens junction protein p120-catenin is implicated in the regulation of cadherin stability, cell migration and inflammatory responses in mammalian epithelial tissues. How these events are coordinated to promote wound repair is not understood. We show that p120 catenin regulates the intrinsic...... migratory properties of primary mouse keratinocytes, but also influences the migratory behavior of neighboring cells by secreted signals. These events are rooted in the ability of p120-catenin to regulate RhoA GTPase activity, which leads to a two-tiered control of cell migration. One restrains cell...... motility via an increase in actin stress fibers, reduction in integrin turnover and an increase in the robustness of focal adhesions. The other is coupled to the secretion of inflammatory cytokines including interleukin-24, which causally enhances randomized cell movements. Taken together, our results...

  20. TRPV4 Regulates Tight Junctions and Affects Differentiation in a Cell Culture Model of the Corneal Epithelium.

    Science.gov (United States)

    Martínez-Rendón, Jacqueline; Sánchez-Guzmán, Erika; Rueda, Angélica; González, James; Gulias-Cañizo, Rosario; Aquino-Jarquín, Guillermo; Castro-Muñozledo, Federico; García-Villegas, Refugio

    2017-07-01

    TRPV4 (transient receptor potential vanilloid 4) is a cation channel activated by hypotonicity, moderate heat, or shear stress. We describe the expression of TRPV4 during the differentiation of a corneal epithelial cell model, RCE1(5T5) cells. TRPV4 is a late differentiation feature that is concentrated in the apical membrane of the outmost cell layer of the stratified epithelia. Ca 2+ imaging experiments showed that TRPV4 activation with GSK1016790A produced an influx of calcium that was blunted by the specific TRPV4 blocker RN-1734. We analyzed the involvement of TRPV4 in RCE1(5T5) epithelial differentiation by measuring the development of transepithelial electrical resistance (TER) as an indicator of the tight junction (TJ) assembly. We showed that TRPV4 activity was necessary to establish the TJ. In differentiated epithelia, activation of TRPV4 increases the TER and the accumulation of claudin-4 in cell-cell contacts. Epidermal Growth Factor (EGF) up-regulates the TER of corneal epithelial cultures, and we show here that TRPV4 activation mimicked this EGF effect. Conversely, TRPV4 inhibition or knock down by specific shRNA prevented the increase in TER. Moreover, TRPP2, an EGF-activated channel that forms heteromeric complexes with TRPV4, is also concentrated in the outmost cell layer of differentiated RCE1(5T5) sheets. This suggests that the EGF regulation of the TJ may involve a heterotetrameric TRPV4-TRPP2 channel. These results demonstrated TRPV4 activity was necessary for the correct establishment of TJ in corneal epithelia and as well as the regulation of both the barrier function of TJ and its ability to respond to EGF. J. Cell. Physiol. 232: 1794-1807, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  1. Estradiol Receptors Regulate Differential Connexin 43 Expression in F98 and C6 Glioma Cell Lines.

    Directory of Open Access Journals (Sweden)

    Zahra Moinfar

    Full Text Available Glioma is the most common malignant primary brain tumour with male preponderance and poor prognosis. Glioma cells express variable amounts of connexin 43 (Cx43 and estrogen receptors (ERs. Both, Cx43 and ERs, play important roles in cell proliferation and migration. Therefore, we investigated the effects of 17-ß estradiol (E2 on Cx43 expression in two glioma cell lines with variable native expression of Cx43.F98 and C6 rat glioma cells were cultured for 24 h in the presence of 10 nM or 100 nM E2, and the E2-antagonist, Fulvestrant. An MTT assay was performed to evaluate cell viability. ERα, ERβ and Cx43 protein expressions were analysed by western blotting and Cx43 mRNA expression was analysed by real-time polymerase chain reaction. To quantify cell migration, an exclusive zone migration assay was used. Functional coupling of cells via gap junctions was examined using whole-cell patch-clamp technique.E2 reduced Cx43 expression in C6 cells, but increased Cx43 expression in F98 cultures. These effects were mediated via ERs. Moreover, E2 promoted C6 cell migration, but it did not affect F98 cell migration. The expression level of ERα was found to be high in C6, but low in F98 cells. ERβ was exclusively expressed in C6 cells. In addition, E2 treatment induced a significant decrease of ERβ in C6 cultures, while it decreased ERα expression in F98 glioma cells.These findings show that E2 differentially modulates Cx43 expression in F98 and C6 glioma cells, likely due to the differential expression of ERs in each of these cell lines. Our findings point to the molecular mechanisms that might contribute to the gender-specific differences in the malignancy of glioma and could have implications for therapeutic strategies against glioma.

  2. miR-146a modulates autoreactive Th17 cell differentiation and regulates organ-specific autoimmunity.

    Science.gov (United States)

    Li, Bo; Wang, Xi; Choi, In Young; Wang, Yu-Chen; Liu, Siyuan; Pham, Alexander T; Moon, Heesung; Smith, Drake J; Rao, Dinesh S; Boldin, Mark P; Yang, Lili

    2017-10-02

    Autoreactive CD4 T cells that differentiate into pathogenic Th17 cells can trigger autoimmune diseases. Therefore, investigating the regulatory network that modulates Th17 differentiation may yield important therapeutic insights. miR-146a has emerged as a critical modulator of immune reactions, but its role in regulating autoreactive Th17 cells and organ-specific autoimmunity remains largely unknown. Here, we have reported that miR-146a-deficient mice developed more severe experimental autoimmune encephalomyelitis (EAE), an animal model of human multiple sclerosis (MS). We bred miR-146a-deficient mice with 2D2 T cell receptor-Tg mice to generate 2D2 CD4 T cells that are deficient in miR-146a and specific for myelin oligodendrocyte glycoprotein (MOG), an autoantigen in the EAE model. miR-146a-deficient 2D2 T cells induced more severe EAE and were more prone to differentiate into Th17 cells. Microarray analysis revealed enhancements in IL-6- and IL-21-induced Th17 differentiation pathways in these T cells. Further study showed that miR-146a inhibited the production of autocrine IL-6 and IL-21 in 2D2 T cells, which in turn reduced their Th17 differentiation. Thus, our study identifies miR-146a as an important molecular brake that blocks the autocrine IL-6- and IL-21-induced Th17 differentiation pathways in autoreactive CD4 T cells, highlighting its potential as a therapeutic target for treating autoimmune diseases.

  3. Transcriptional up-regulation of restin by all-trans retinoic acid through STAT1 in cancer cell differentiation process

    International Nuclear Information System (INIS)

    Fu Haiyan; Yang Guodong; Lu Fan; Wang Ruihua; Yao Libo; Lu Zifan

    2006-01-01

    RESTIN, a member of the melanoma-associated antigen superfamily, is a nuclear protein induced by atRA (all-trans retinoic acid) in HL60 cells. HeLa cells stably transfected with restin results in G1 cell cycle arrest. How this gene is regulated by atRA in the cell differentiation process is still unclear. In this study, we observed that up-regulation of restin was present during the atRA-induced HL60 cell differentiation process, suggesting the functional relevance between RESTIN and atRA-induced cellular effects. In order to further define the transcriptional regulation of restin by atRA, we analyzed the promoter region of restin. About 2.1 kb 5' flanking sequence of this gene was cloned into vector pGL3 and its core promoter region was identified through systemic deletions. Interestingly, restin promoter containing several potential consensus-binding sites of STAT-1α was activated by atRA in ER + MCF-7 cells but not in ER - MDA-MB-231 cells, over-expression of STAT-1α in latter rescued the activation effect of restin promoter in response to atRA and IFNγ. Our evidence supported that STAT-1α plays an important role in the atRA-induced transcriptional up-regulation of restin, which was associated with the atRA-induced HL60 cell differentiation and potentially mediated the downstream effects of atRA signal pathway via STAT-1α in some cancer cells

  4. Cholesterol and phytosterols differentially regulate the expression of caveolin 1 and a downstream prostate cell growth-suppressor gene

    Science.gov (United States)

    Ifere, Godwin O.; Equan, Anita; Gordon, Kereen; Nagappan, Peri; Igietseme, Joseph U.; Ananaba, Godwin A.

    2010-01-01

    Background The purpose of our study was to show the distinction between the apoptotic and anti-proliferative signaling of phytosterols and cholesterol enrichment in prostate cancer cell lines, mediated by the differential transcription of caveolin-1, and N-myc downstream regulated gene1 (NDRG1), a pro-apoptotic androgen-regulated tumor suppressor. Methods PC-3 and DU145 cells were treated with sterols (cholesterol and phytosterols) for 72 h, followed by trypan blue dye exclusion measurement of necrosis and cell growth measured with a Coulter counter. Sterol induction of cell growth-suppressor gene expression was evaluated by mRNA transcription using RT-PCR, while cell cycle analysis was performed by FACS analysis. Altered expression of Ndrg1 protein was confirmed by Western blot analysis. Apoptosis was evaluated by real time RT-PCR amplification of P53, Bcl-2 gene and its related pro- and anti-apoptotic family members. Results Physiological doses (16 µM) of cholesterol and phytosterols were not cytotoxic in these cells. Cholesterol enrichment promoted cell growth (Pphytosterols significantly induced growth-suppression (Pphytosterols decreased mitotic subpopulations. We demonstrated for the first time that cholesterols concertedly attenuated the expression of caveolin-1(cav-1) and NDRG1 genes in both prostate cancer cell lines. Phytosterols had the opposite effect by inducing overexpression of cav-1, a known mediator of androgen-dependent signals that presumably control cell growth or apoptosis. Conclusions Cholesterol and phytosterol treatment differentially regulated the growth of prostate cancer cells and the expression of p53 and cav-1, a gene that regulates androgen-regulated signals. These sterols also differentially regulated cell cycle arrest, downstream pro-apoptotic androgen-regulated tumor-suppressor, NDRG1 suggesting that cav-1 may mediate pro-apoptotic NDRG1 signals. Elucidation of the mechanism for sterol modulation of growth and apoptosis signaling

  5. MicroRNAs as Regulators of Adipogenic Differentiation of Mesenchymal Stem Cells

    DEFF Research Database (Denmark)

    Hamam, Dana; Ali, Dalia; Kassem, Moustapha

    2015-01-01

    MicroRNAs (miRNAs) constitute complex regulatory network, fine tuning the expression of a myriad of genes involved in different biological and physiological processes, including stem cell differentiation. Mesenchymal stem cells (MSCs) are multipotent stem cells present in the bone marrow stroma......, and the stroma of many other tissues, and can give rise to a number of mesoderm-type cells including adipocytes and osteoblasts, which form medullary fat and bone tissues, respectively. The role of bone marrow fat in bone mass homeostasis is an area of intensive investigation with the aim of developing novel...

  6. Cytokine-Regulated GADD45G Induces Differentiation and Lineage Selection in Hematopoietic Stem Cells

    Directory of Open Access Journals (Sweden)

    Frederic B. Thalheimer

    2014-07-01

    Full Text Available The balance of self-renewal and differentiation in long-term repopulating hematopoietic stem cells (LT-HSC must be strictly controlled to maintain blood homeostasis and to prevent leukemogenesis. Hematopoietic cytokines can induce differentiation in LT-HSCs; however, the molecular mechanism orchestrating this delicate balance requires further elucidation. We identified the tumor suppressor GADD45G as an instructor of LT-HSC differentiation under the control of differentiation-promoting cytokine receptor signaling. GADD45G immediately induces and accelerates differentiation in LT-HSCs and overrides the self-renewal program by specifically activating MAP3K4-mediated MAPK p38. Conversely, the absence of GADD45G enhances the self-renewal potential of LT-HSCs. Videomicroscopy-based tracking of single LT-HSCs revealed that, once GADD45G is expressed, the development of LT-HSCs into lineage-committed progeny occurred within 36 hr and uncovered a selective lineage choice with a severe reduction in megakaryocytic-erythroid cells. Here, we report an unrecognized role of GADD45G as a central molecular linker of extrinsic cytokine differentiation and lineage choice control in hematopoiesis.

  7. c-Myb Regulates the T-Bet-Dependent Differentiation Program in B Cells to Coordinate Antibody Responses

    Directory of Open Access Journals (Sweden)

    Dana Piovesan

    2017-04-01

    Full Text Available Summary: Humoral immune responses are tailored to the invading pathogen through regulation of key transcription factors and their networks. This is critical to establishing effective antibody-mediated responses, yet it is unknown how B cells integrate pathogen-induced signals to drive or suppress transcriptional programs specialized for each class of pathogen. Here, we detail the key role of the transcription factor c-Myb in regulating the T-bet-mediated anti-viral program. Deletion of c-Myb in mature B cells significantly increased serum IgG2c and CXCR3 expression by upregulating T-bet, normally suppressed during Th2-cell-mediated responses. Enhanced expression of T-bet resulted in aberrant plasma cell differentiation within the germinal center, mediated by CXCR3 expression. These findings identify a dual role for c-Myb in limiting inappropriate effector responses while coordinating plasma cell differentiation with germinal center egress. Identifying such intrinsic regulators of specialized antibody responses can assist in vaccine design and therapeutic intervention in B-cell-mediated immune disorders. : Piovesan et al. examine how B cells establish transcriptional programs that result in tailored responses to invading pathogens. The authors find that the transcription factor c-Myb represses the T-bet-mediated anti-viral program in B cells. c-Myb limits inappropriate effector responses while coordinating plasma cell differentiation with germinal center egress. Keywords: B cells, c-Myb, T-bet, immunoglobulin, CXCR3, plasma cell, germinal center

  8. Delayed Mesoderm and Erythroid Differentiation of Murine Embryonic Stem Cells in the Absence of the Transcriptional Regulator FUBP1

    Directory of Open Access Journals (Sweden)

    Josephine Wesely

    2017-01-01

    Full Text Available The transcriptional regulator far upstream binding protein 1 (FUBP1 is essential for fetal and adult hematopoietic stem cell (HSC self-renewal, and the constitutive absence of FUBP1 activity during early development leads to embryonic lethality in homozygous mutant mice. To investigate the role of FUBP1 in murine embryonic stem cells (ESCs and in particular during differentiation into hematopoietic lineages, we generated Fubp1 knockout (KO ESC clones using CRISPR/Cas9 technology. Although FUBP1 is expressed in undifferentiated ESCs and during spontaneous differentiation following aggregation into embryoid bodies (EBs, absence of FUBP1 did not affect ESC maintenance. Interestingly, we observed a delayed differentiation of FUBP1-deficient ESCs into the mesoderm germ layer, as indicated by impaired expression of several mesoderm markers including Brachyury at an early time point of ESC differentiation upon aggregation to EBs. Coculture experiments with OP9 cells in the presence of erythropoietin revealed a diminished differentiation capacity of Fubp1 KO ESCs into the erythroid lineage. Our data showed that FUBP1 is important for the onset of mesoderm differentiation and maturation of hematopoietic progenitor cells into the erythroid lineage, a finding that is supported by the phenotype of FUBP1-deficient mice.

  9. Muscle Satellite Cell Protein Teneurin-4 Regulates Differentiation During Muscle Regeneration.

    Science.gov (United States)

    Ishii, Kana; Suzuki, Nobuharu; Mabuchi, Yo; Ito, Naoki; Kikura, Naomi; Fukada, So-Ichiro; Okano, Hideyuki; Takeda, Shin'ichi; Akazawa, Chihiro

    2015-10-01

    Satellite cells are maintained in an undifferentiated quiescent state, but during muscle regeneration they acquire an activated stage, and initiate to proliferate and differentiate as myoblasts. The transmembrane protein teneurin-4 (Ten-4) is specifically expressed in the quiescent satellite cells; however, its cellular and molecular functions remain unknown. We therefore aimed to elucidate the function of Ten-4 in muscle satellite cells. In the tibialis anterior (TA) muscle of Ten-4-deficient mice, the number and the size of myofibers, as well as the population of satellite cells, were reduced with/without induction of muscle regeneration. Furthermore, we found an accelerated activation of satellite cells in the regenerated Ten-4-deficient TA muscle. The cell culture analysis using primary satellite cells showed that Ten-4 suppressed the progression of myogenic differentiation. Together, our findings revealed that Ten-4 functions as a crucial player in maintaining the quiescence of muscle satellite cells. © 2015 The Authors STEM CELLS published by Wiley Periodicals, Inc. on behalf of AlphaMed Press.

  10. Muscle Satellite Cell Protein Teneurin‐4 Regulates Differentiation During Muscle Regeneration

    Science.gov (United States)

    Ishii, Kana; Suzuki, Nobuharu; Mabuchi, Yo; Ito, Naoki; Kikura, Naomi; Fukada, So‐ichiro; Okano, Hideyuki; Takeda, Shin'ichi

    2015-01-01

    Abstract Satellite cells are maintained in an undifferentiated quiescent state, but during muscle regeneration they acquire an activated stage, and initiate to proliferate and differentiate as myoblasts. The transmembrane protein teneurin‐4 (Ten‐4) is specifically expressed in the quiescent satellite cells; however, its cellular and molecular functions remain unknown. We therefore aimed to elucidate the function of Ten‐4 in muscle satellite cells. In the tibialis anterior (TA) muscle of Ten‐4‐deficient mice, the number and the size of myofibers, as well as the population of satellite cells, were reduced with/without induction of muscle regeneration. Furthermore, we found an accelerated activation of satellite cells in the regenerated Ten‐4‐deficient TA muscle. The cell culture analysis using primary satellite cells showed that Ten‐4 suppressed the progression of myogenic differentiation. Together, our findings revealed that Ten‐4 functions as a crucial player in maintaining the quiescence of muscle satellite cells. Stem Cells 2015;33:3017–3027 PMID:26013034

  11. Gmnc Is a Master Regulator of the Multiciliated Cell Differentiation Program

    NARCIS (Netherlands)

    Zhou, Feng; Narasimhan, Vijay; Shboul, Mohammad; Chong, Yan Ling; Reversade, Bruno; Roy, Sudipto

    2015-01-01

    Multiciliated cells (MCCs) differentiate hundreds of motile cilia that generate mechanical force required to drive fluid movement over epithelia [1, 2]. For example, metachronal beating of MCC cilia in the mammalian airways clears mucus that traps inhaled pathogens and pollutants. Consequently,

  12. Leptin differentially regulates STAT3 activation in the ob/ob mice adipose mesenchymal stem cells

    Science.gov (United States)

    Leptin-deficient genetically obese ob/ob mice exhibit adipocyte hypertrophy and hyperplasia as well as elevated adipose tissue and systemic inflammation. Studies have shown that multipotent stem cells isolated from adult adipose tissue can differentiate into adipocytes ex vivo and thereby contribute...

  13. [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.

  14. Differential and Cooperative Cell Adhesion Regulates Cellular Pattern in Sensory Epithelia.

    Science.gov (United States)

    Togashi, Hideru

    2016-01-01

    Animal tissues are composed of multiple cell types arranged in complex and elaborate patterns. In sensory epithelia, including the auditory epithelium and olfactory epithelium, different types of cells are arranged in unique mosaic patterns. These mosaic patterns are evolutionarily conserved, and are thought to be important for hearing and olfaction. Recent progress has provided accumulating evidence that the cellular pattern formation in epithelia involves cell rearrangements, movements, and shape changes. These morphogenetic processes are largely mediated by intercellular adhesion systems. Differential adhesion and cortical tension have been proposed to promote cell rearrangements. Many different types of cells in tissues express various types of cell adhesion molecules. Although cooperative mechanisms between multiple adhesive systems are likely to contribute to the production of complex cell patterns, our current understanding of the cooperative roles between multiple adhesion systems is insufficient to entirely explain the complex mechanisms underlying cellular patterning. Recent studies have revealed that nectins, in cooperation with cadherins, are crucial for the mosaic cellular patterning in sensory organs. The nectin and cadherin systems are interacted with one another, and these interactions provide cells with differential adhesive affinities for complex cellular pattern formations in sensory epithelia, which cannot be achieved by a single mechanism.

  15. The regulation of mitochondrial transcription factor A (Tfam) expression during skeletal muscle cell differentiation.

    Science.gov (United States)

    Collu-Marchese, Melania; Shuen, Michael; Pauly, Marion; Saleem, Ayesha; Hood, David A

    2015-05-19

    The ATP demand required for muscle development is accommodated by elevations in mitochondrial biogenesis, through the co-ordinated activities of the nuclear and mitochondrial genomes. The most important transcriptional activator of the mitochondrial genome is mitochondrial transcription factor A (Tfam); however, the regulation of Tfam expression during muscle differentiation is not known. Thus, we measured Tfam mRNA levels, mRNA stability, protein expression and localization and Tfam transcription during the progression of muscle differentiation. Parallel 2-fold increases in Tfam protein and mRNA were observed, corresponding with 2-3-fold increases in mitochondrial content. Transcriptional activity of a 2051 bp promoter increased during this differentiation period and this was accompanied by a 3-fold greater Tfam mRNA stabilization. Interestingly, truncations of the promoter at 1706 bp, 978 bp and 393 bp promoter all exhibited 2-3-fold higher transcriptional activity than the 2051 bp construct, indicating the presence of negative regulatory elements within the distal 350 bp of the promoter. Activation of AMP kinase augmented Tfam transcription within the proximal promoter, suggesting the presence of binding sites for transcription factors that are responsive to cellular energy state. During differentiation, the accumulating Tfam protein was progressively distributed to the mitochondrial matrix where it augmented the expression of mtDNA and COX (cytochrome c oxidase) subunit I, an mtDNA gene product. Our data suggest that, during muscle differentiation, Tfam protein levels are regulated by the availability of Tfam mRNA, which is controlled by both transcription and mRNA stability. Changes in energy state and Tfam localization also affect Tfam expression and action in differentiating myotubes. © 2015 Authors.

  16. Src Family Kinases and p38 Mitogen-Activated Protein Kinases Regulate Pluripotent Cell Differentiation in Culture.

    Directory of Open Access Journals (Sweden)

    Boon Siang Nicholas Tan

    Full Text Available Multiple pluripotent cell populations, which together comprise the pluripotent cell lineage, have been identified. The mechanisms that control the progression between these populations are still poorly understood. The formation of early primitive ectoderm-like (EPL cells from mouse embryonic stem (mES cells provides a model to understand how one such transition is regulated. EPL cells form from mES cells in response to l-proline uptake through the transporter Slc38a2. Using inhibitors of cell signaling we have shown that Src family kinases, p38 MAPK, ERK1/2 and GSK3β are required for the transition between mES and EPL cells. ERK1/2, c-Src and GSK3β are likely to be enforcing a receptive, primed state in mES cells, while Src family kinases and p38 MAPK are involved in the establishment of EPL cells. Inhibition of these pathways prevented the acquisition of most, but not all, features of EPL cells, suggesting that other pathways are required. L-proline activation of differentiation is mediated through metabolism and changes to intracellular metabolite levels, specifically reactive oxygen species. The implication of multiple signaling pathways in the process suggests a model in which the context of Src family kinase activation determines the outcomes of pluripotent cell differentiation.

  17. Src Family Kinases and p38 Mitogen-Activated Protein Kinases Regulate Pluripotent Cell Differentiation in Culture

    Science.gov (United States)

    Tan, Boon Siang Nicholas; Kwek, Joly; Wong, Chong Kum Edwin; Saner, Nicholas J.; Yap, Charlotte; Felquer, Fernando; Morris, Michael B.; Gardner, David K.; Rathjen, Peter D.; Rathjen, Joy

    2016-01-01

    Multiple pluripotent cell populations, which together comprise the pluripotent cell lineage, have been identified. The mechanisms that control the progression between these populations are still poorly understood. The formation of early primitive ectoderm-like (EPL) cells from mouse embryonic stem (mES) cells provides a model to understand how one such transition is regulated. EPL cells form from mES cells in response to l-proline uptake through the transporter Slc38a2. Using inhibitors of cell signaling we have shown that Src family kinases, p38 MAPK, ERK1/2 and GSK3β are required for the transition between mES and EPL cells. ERK1/2, c-Src and GSK3β are likely to be enforcing a receptive, primed state in mES cells, while Src family kinases and p38 MAPK are involved in the establishment of EPL cells. Inhibition of these pathways prevented the acquisition of most, but not all, features of EPL cells, suggesting that other pathways are required. L-proline activation of differentiation is mediated through metabolism and changes to intracellular metabolite levels, specifically reactive oxygen species. The implication of multiple signaling pathways in the process suggests a model in which the context of Src family kinase activation determines the outcomes of pluripotent cell differentiation. PMID:27723793

  18. Situational Awareness: Regulation of the Myb Transcription Factor in Differentiation, the Cell Cycle and Oncogenesis

    Energy Technology Data Exchange (ETDEWEB)

    George, Olivia L.; Ness, Scott A., E-mail: sness@salud.unm.edu [Department of Internal Medicine, Section of Molecular Medicine, University of New Mexico Health Sciences Center, MSC07 4025-CRF 121, 1 University of New Mexico, Albuquerque, NM 87131 (United States)

    2014-10-02

    This review summarizes the mechanisms that control the activity of the c-Myb transcription factor in normal cells and tumors, and discusses how c-Myb plays a role in the regulation of the cell cycle. Oncogenic versions of c-Myb contribute to the development of leukemias and solid tumors such as adenoid cystic carcinoma, breast cancer and colon cancer. The activity and specificity of the c-Myb protein seems to be controlled through changes in protein-protein interactions, so understanding how it is regulated could lead to the development of novel therapeutic strategies.

  19. Regulation of proximal tubular cell differentiation and proliferation in primary culture by matrix stiffness and ECM components.

    Science.gov (United States)

    Chen, Wan-Chun; Lin, Hsi-Hui; Tang, Ming-Jer

    2014-09-15

    To explore whether matrix stiffness affects cell differentiation, proliferation, and transforming growth factor (TGF)-β1-induced epithelial-mesenchymal transition (EMT) in primary cultures of mouse proximal tubular epithelial cells (mPTECs), we used a soft matrix made from monomeric collagen type I-coated polyacrylamide gel or matrigel (MG). Both kinds of soft matrix benefited primary mPTECs to retain tubular-like morphology with differentiation and growth arrest and to evade TGF-β1-induced EMT. However, the potent effect of MG on mPTEC differentiation was suppressed by glutaraldehyde-induced cross-linking and subsequently stiffening MG or by an increasing ratio of collagen in the soft mixed gel. Culture media supplemented with MG also helped mPTECs to retain tubular-like morphology and a differentiated phenotype on stiff culture dishes as soft MG did. We further found that the protein level and activity of ERK were scaled with the matrix stiffness. U-0126, a MEK inhibitor, abolished the stiff matrix-induced dedifferentiation and proliferation. These data suggest that the ERK signaling pathway plays a vital role in matrix stiffness-regulated cell growth and differentiation. Taken together, both compliant property and specific MG signals from the matrix are required for the regulation of epithelial differentiation and proliferation. This study provides a basic understanding of how physical and chemical cues derived from the extracellular matrix regulate the physiological function of proximal tubules and the pathological development of renal fibrosis. Copyright © 2014 the American Physiological Society.

  20. DIDO as a Switchboard that Regulates Self-Renewal and Differentiation in Embryonic Stem Cells.

    Science.gov (United States)

    Fütterer, Agnes; de Celis, Jésus; Navajas, Rosana; Almonacid, Luis; Gutiérrez, Julio; Talavera-Gutiérrez, Amaia; Pacios-Bras, Cristina; Bernascone, Ilenia; Martin-Belmonte, Fernando; Martinéz-A, Carlos

    2017-04-11

    Transition from symmetric to asymmetric cell division requires precise coordination of differential gene expression. We show that embryonic stem cells (ESCs) mainly express DIDO3 and that their differentiation after leukemia inhibitory factor withdrawal requires DIDO1 expression. C-terminal truncation of DIDO3 (Dido3ΔCT) impedes ESC differentiation while retaining self-renewal; small hairpin RNA-Dido1 ESCs have the same phenotype. Dido3ΔCT ESC differentiation is rescued by ectopic expression of DIDO3, which binds the Dido locus via H3K4me3 and RNA POL II and induces DIDO1 expression. DIDO1, which is exported to cytoplasm, associates with, and is N-terminally phosphorylated by PKCiota. It binds the E3 ubiquitin ligase WWP2, which contributes to cell fate by OCT4 degradation, to allow expression of primitive endoderm (PE) markers. PE formation also depends on phosphorylated DIDO3 localization to centrosomes, which ensures their correct positioning for PE cell polarization. We propose that DIDO isoforms act as a switchboard that regulates genetic programs for ESC transition from pluripotency maintenance to promotion of differentiation. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  1. RANKL regulates differentiation of microfold cells in mouse nasopharynx-associated lymphoid tissue (NALT).

    Science.gov (United States)

    Mutoh, Mami; Kimura, Shunsuke; Takahashi-Iwanaga, Hiromi; Hisamoto, Meri; Iwanaga, Toshihiko; Iida, Junichiro

    2016-04-01

    Murine nasopharynx-associated lymphoid tissue (NALT), located at the base of the nasal cavity, serves as a major site for the induction of mucosal immune responses against airway antigens. The follicle-associated epithelium (FAE) covering the luminal surface of NALT is characterized by the presence of microfold cells (M cells), which take up and transport luminal antigens to lymphocytes. Glycoprotein 2 (GP2) has recently been identified as a reliable marker for M cells in Peyer's patches of the intestine. However, the expression of GP2 and other functional molecules in the M cells of NALT has not yet been examined. We have immunohistochemically detected GP2-expressing cells in the FAE of NALT and the simultaneous expression of other intestinal M-cell markers, namely Tnfaip2, CCL9, and Spi-B. These cells have been further identified as M cells because of their higher uptake capacity of luminal microbeads. Electron microscopic observations have shown that GP2-expressing cells on the FAE display morphological features typical of M cells: they possess short microvilli and microfolds on the luminal surface and are closely associated with intraepithelial lymphocytes. We have also found that the receptor activator of nuclear factor kappa-B ligand (RANKL) is expressed by stromal cells underneath the FAE, which provides its receptor RANK. The administration of RANKL markedly increases the number of GP2(+)Tnfaip2(+) cells on the NALT FAE and that of intestinal M cells. These results suggest that GP2(+)Tnfaip2(+) cells in NALT are equivalent to intestinal M cells, and that RANKL-RANK signaling induces their differentiation.

  2. CHD1 regulates cell fate determination by activation of differentiation-induced genes

    DEFF Research Database (Denmark)

    Baumgart, Simon J; Najafova, Zeynab; Hossan, Tareq

    2017-01-01

    The coordinated temporal and spatial activation of gene expression is essential for proper stem cell differentiation. The Chromodomain Helicase DNA-binding protein 1 (CHD1) is a chromatin remodeler closely associated with transcription and nucleosome turnover downstream of the transcriptional start...... site (TSS). In this study, we show that CHD1 is required for the induction of osteoblast-specific gene expression, extracellular-matrix mineralization and ectopic bone formation in vivo. Genome-wide occupancy analyses revealed increased CHD1 occupancy around the TSS of differentiation-activated genes....... Furthermore, we observed that CHD1-dependent genes are mainly induced during osteoblast differentiation and are characterized by higher levels of CHD1 occupancy around the TSS. Interestingly, CHD1 depletion resulted in increased pausing of RNA Polymerase II (RNAPII) and decreased H2A.Z occupancy close...

  3. CHD1 regulates cell fate determination by activation of differentiation-induced genes.

    Science.gov (United States)

    Baumgart, Simon J; Najafova, Zeynab; Hossan, Tareq; Xie, Wanhua; Nagarajan, Sankari; Kari, Vijayalakshmi; Ditzel, Nicholas; Kassem, Moustapha; Johnsen, Steven A

    2017-07-27

    The coordinated temporal and spatial activation of gene expression is essential for proper stem cell differentiation. The Chromodomain Helicase DNA-binding protein 1 (CHD1) is a chromatin remodeler closely associated with transcription and nucleosome turnover downstream of the transcriptional start site (TSS). In this study, we show that CHD1 is required for the induction of osteoblast-specific gene expression, extracellular-matrix mineralization and ectopic bone formation in vivo. Genome-wide occupancy analyses revealed increased CHD1 occupancy around the TSS of differentiation-activated genes. Furthermore, we observed that CHD1-dependent genes are mainly induced during osteoblast differentiation and are characterized by higher levels of CHD1 occupancy around the TSS. Interestingly, CHD1 depletion resulted in increased pausing of RNA Polymerase II (RNAPII) and decreased H2A.Z occupancy close to the TSS, but not at enhancer regions. These findings reveal a novel role for CHD1 during osteoblast differentiation and provide further insights into the intricacies of epigenetic regulatory mechanisms controlling cell fate determination. © The Author(s) 2017. Published by Oxford University Press on behalf of Nucleic Acids Research.

  4. Differential regulation of genomic imprinting by TET proteins in embryonic stem cells.

    Science.gov (United States)

    Liu, Lizhi; Mao, Shi-Qing; Ray, Chelsea; Zhang, Yu; Bell, Fong T; Ng, Sheau-Fang; Xu, Guo-Liang; Li, Xiajun

    2015-09-01

    TET proteins have been found to play an important role in active demethylation at CpG sites in mammals. There are some reports implicating their functions in removal of DNA methylation imprint at the imprinted regions in the germline. However, it is not well established whether TET proteins can also be involved in demethylation of DNA methylation imprint in embryonic stem (ES) cells. Here we report that loss of TET proteins caused a significant increase in DNA methylation at the Igf2-H19 imprinted region in ES cells. We also observed a variable increase in DNA methylation at the Peg1 imprinted region in the ES clones devoid of TET proteins, in particular in the differentiated ES cells. By contrast, we did not observe a significant increase of DNA methylation imprint at the Peg3, Snrpn and Dlk1-Dio3 imprinted regions in ES cells lacking TET proteins. Interestingly, loss of TET proteins did not result in a significant increase of DNA methylation imprint at the Igf2-H19 and Peg1 imprinted regions in the embryoid bodies (EB). Therefore, TET proteins seem to be differentially involved in maintaining DNA methylation imprint at a subset of imprinted regions in ES cells and EBs. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

  5. Differential regulation of ANG2 and VEGF-A in human granulosa lutein cells by choriogonadotropin.

    Science.gov (United States)

    Pietrowski, D; Keck, C

    2004-04-01

    The growth and development of the corpus luteum after rupture of the follicle is a highly regulated process characterised by a rapid vascularization of the follicle surrounding granulosa cells. Vascularization is regulated by a large number of growth factors and cytokines whereas members of the angiopoietin family and VEGF-A are reported to play a principal role. The gonadotropic hormones luteinizing hormone and choriogonadotropin are reported to be essential for corpus luteum formation. In this study we investigated by RT PCR if the growth factors PGF, PDGF-A, PDGF-B, VEGF-A, VEGF-B, VEGF-C, VEGF-D, ANG1, ANG2, ANG3 and ANG4 are expressed in granulosa cells. We show the expression of VEGF-A, VEGF-B, PDGF-A, ANG1 and ANG2 in granulosa cells. Using RT-PCR and Real-Time PCR we demonstrate that angiopoietin 2 is downregulated in human granulosa cells in vitro after choriogonadotropin treatment whereas the expression of angiopoietin 1 is not significantly altered. The expression of VEGF on the RNA- and on the protein level was determined. It was shown that in granulosa cells VEGF is upregulated after choriogonadotropin treatment on the RNA level and that increasing concentrations of choriogonadotropin from 0 to 10 U/ml leads to an increasing amount of VEGF in the cell culture supernatants. The amount of VEGF in the supernatants reaches a plateau at 0.5 U/ml and is increased only slightly and not significantly after treatment of the cells with 10 U/ml choriogonadotropin compared to 0.5 U/ml. In total these findings suggests that in granulosa cells the mRNA of various growth factors is detectable by RT-PCR and that VEGF-A and ANG2 is regulated by the gonadotropic hormone choriogonadotropin. These findings may add impact on the hypothesis of choriogonadotropin as a novel angiogenic factor.

  6. Planar cell polarity proteins differentially regulate extracellular matrix organization and assembly during zebrafish gastrulation.

    Science.gov (United States)

    Dohn, Michael R; Mundell, Nathan A; Sawyer, Leah M; Dunlap, Julie A; Jessen, Jason R

    2013-11-01

    Zebrafish gastrulation cell movements occur in the context of dynamic changes in extracellular matrix (ECM) organization and require the concerted action of planar cell polarity (PCP) proteins that regulate cell elongation and mediolateral alignment. Data obtained using Xenopus laevis gastrulae have shown that integrin-fibronectin interactions underlie the formation of polarized cell protrusions necessary for PCP and have implicated PCP proteins themselves as regulators of ECM. By contrast, the relationship between establishment of PCP and ECM assembly/remodeling during zebrafish gastrulation is unclear. We previously showed that zebrafish embryos carrying a null mutation in the four-pass transmembrane PCP protein vang-like 2 (vangl2) exhibit increased matrix metalloproteinase activity and decreased immunolabeling of fibronectin. These data implicated for the first time a core PCP protein in the regulation of pericellular proteolysis of ECM substrates and raised the question of whether other zebrafish PCP proteins also impact ECM organization. In Drosophila melanogaster, the cytoplasmic PCP protein Prickle binds Van Gogh and regulates its function. Here we report that similar to vangl2, loss of zebrafish prickle1a decreases fibronectin protein levels in gastrula embryos. We further show that Prickle1a physically binds Vangl2 and regulates both the subcellular distribution and total protein level of Vangl2. These data suggest that the ability of Prickle1a to impact fibronectin organization is at least partly due to effects on Vangl2. In contrast to loss of either Vangl2 or Prickle1a function, we find that glypican4 (a Wnt co-receptor) and frizzled7 mutant gastrula embryos with disrupted non-canonical Wnt signaling exhibit the opposite phenotype, namely increased fibronectin assembly. Our data show that glypican4 mutants do not have decreased proteolysis of ECM substrates, but instead have increased cell surface cadherin protein expression and increased intercellular

  7. MiRNA-20a promotes osteogenic differentiation of human mesenchymal stem cells by co-regulating BMP signaling.

    Science.gov (United States)

    Zhang, Jin-fang; Fu, Wei-ming; He, Ming-liang; Xie, Wei-dong; Lv, Qing; Wan, Gang; Li, Guo; Wang, Hua; Lu, Gang; Hu, Xiang; Jiang, Su; Li, Jian-na; Lin, Marie C M; Zhang, Ya-ou; Kung, Hsiang-fu

    2011-01-01

    Osteogenic differentiation of mesenchymal stem cells (MSCs) is a complex process, which is regulated by various factors including microRNAs. Our preliminary data showed that the expression of endogenous miR-20a was increased during the course of osteogenic differentiation. Simultaneously, the expression of osteoblast markers and regulators BMP2, BMP4, Runx2, Osx, OCN and OPN was also elevated whereas adipocyte markers PPARγ and osteoblast antagonist, Bambi and Crim1, were downregulated, thereby suggesting that miR-20a plays an important role in regulating osteoblast differentiation. To validate this hypothesis, we tested its effects on osteogenic differentiation by introducing miR-20a mimics and lentiviral-miR20a-expression vectors into hMSCs. We showed that miR-20a promoted osteogenic differentiation by the upregulation of BMP/Runx2 signaling. We performed bioinformatics analysis and predicted that PPARγ, Bambi and Crim1 would be potential targets of miR-20a. PPARγ is a negative regulator of BMP/Runx2 signaling whereas Bambi or Crim1 are antagonists of the BMP pathway. Furthermore, we confirmed that all these molecules were indeed the targets of miR-20a by luciferase reporter, quantitative RT-PCR and western blot assays. Similarly to miR-20a overexpression, the osteogenesis was enhanced by the silence of PPARγ, Bambi or Crim1 by specific siRNAs. Taken together, for the first time, we demonstrated that miR-20a promoted the osteogenesis of hMSCs in a co-regulatory pattern by targeting PPARγ, Bambi and Crim1, the negative regulators of BMP signaling.

  8. SOX4 regulates gonad morphogenesis and promotes male germ cell differentiation in mice.

    Science.gov (United States)

    Zhao, Liang; Arsenault, Michel; Ng, Ee Ting; Longmuss, Enya; Chau, Tevin Chui-Ying; Hartwig, Sunny; Koopman, Peter

    2017-03-01

    The group C SOX transcription factors SOX4, -11 and -12 play important and mutually overlapping roles in development of a number of organs. Here, we examined the role of SoxC genes during gonadal development in mice. All three genes were expressed in developing gonads of both sexes, predominantly in somatic cells, with Sox4 being most strongly expressed. Sox4 deficiency resulted in elongation of both ovaries and testes, and an increased number of testis cords. While female germ cells entered meiosis normally, male germ cells showed reduced levels of differentiation markers Nanos2 and Dnmt3l and increased levels of pluripotency genes Cripto and Nanog, suggesting that SOX4 may normally act to restrict the pluripotency period of male germ cells and ensure their proper differentiation. Finally, our data reveal that SOX4 (and, to a lesser extent, SOX11 and -12) repressed transcription of the sex-determining gene Sox9 via an upstream testis-specific enhancer core (TESCO) element in fetal gonads, raising the possibility that SOXC proteins may function as transcriptional repressors in a context-dependent manner. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. CD4+ T‐cell activation is differentially modulated by bacteria‐primed dendritic cells, but is generally down‐regulated by n‐3 polyunsaturated fatty acids

    DEFF Research Database (Denmark)

    Pedersen, Susanne Brix; Lund, Pia; Kjær, Tanja

    2010-01-01

    provided by dendritic cells (DCs). Upon interaction with DCs primed by different concentrations and species of gut bacteria, CD4+ T cells were activated according to the type of DC stimulus. The levels of CD80 were found to correlate to the levels of expression of CD28 and to the proliferation of CD4+ T......, thereby affecting and shaping activation of acquired immunity by differential regulation of proliferation and costimulatory molecule expression in CD4+ T cells....

  10. ALS/FTLD-linked TDP-43 regulates neurite morphology and cell survival in differentiated neurons

    Energy Technology Data Exchange (ETDEWEB)

    Han, Jeong-Ho; Yu, Tae-Hoon; Ryu, Hyun-Hee; Jun, Mi-Hee; Ban, Byung-Kwan [Department of Biotechnology, College of Life Science and Nanotechnology, Hannam University, Dajeon 305-811 (Korea, Republic of); Jang, Deok-Jin [Department of Applied Biology, College of Ecology and Environment, Kyungpook National University, 386, Gajang-dong, Sangju-si, Kyungbuk 742-711 (Korea, Republic of); Lee, Jin-A, E-mail: leeja@hnu.kr [Department of Biotechnology, College of Life Science and Nanotechnology, Hannam University, Dajeon 305-811 (Korea, Republic of)

    2013-08-01

    Tar-DNA binding protein of 43 kDa (TDP-43) has been characterized as a major component of protein aggregates in brains with neurodegenerative diseases such as frontotemporal lobar degeneration (FTLD) and amyotrophic lateral sclerosis (ALS). However, physiological roles of TDP-43 and early cellular pathogenic effects caused by disease associated mutations in differentiated neurons are still largely unknown. Here, we investigated the physiological roles of TDP-43 and the effects of missense mutations associated with diseases in differentiated cortical neurons. The reduction of TDP-43 by siRNA increased abnormal neurites and decreased cell viability. ALS/FTLD-associated missense mutant proteins (A315T, Q331K, and M337V) were partially mislocalized to the cytosol and neurites when compared to wild-type and showed abnormal neurites similar to those observed in cases of loss of TDP-43. Interestingly, cytosolic expression of wild-type TDP-43 with mutated nuclear localization signals also induced abnormal neurtie morphology and reduction of cell viability. However, there was no significant difference in the effects of cytosolic expression in neuronal morphology and cell toxicity between wild-type and missense mutant proteins. Thus, our results suggest that mislocalization of missense mutant TDP-43 may contribute to loss of TDP-43 function and affect neuronal morphology, probably via dominant negative action before severe neurodegeneration in differentiated cortical neurons. Highlights: • The function of nuclear TDP-43 in neurite morphology in mature neurons. • Partial mislocalization of TDP-43 missense mutants into cytosol from nucleus. • Abnormal neurite morphology caused by missense mutants of TDP-43. • The effect of cytosolic expression of TDP-43 in neurite morphology and in cell survival.

  11. ALS/FTLD-linked TDP-43 regulates neurite morphology and cell survival in differentiated neurons

    International Nuclear Information System (INIS)

    Han, Jeong-Ho; Yu, Tae-Hoon; Ryu, Hyun-Hee; Jun, Mi-Hee; Ban, Byung-Kwan; Jang, Deok-Jin; Lee, Jin-A

    2013-01-01

    Tar-DNA binding protein of 43 kDa (TDP-43) has been characterized as a major component of protein aggregates in brains with neurodegenerative diseases such as frontotemporal lobar degeneration (FTLD) and amyotrophic lateral sclerosis (ALS). However, physiological roles of TDP-43 and early cellular pathogenic effects caused by disease associated mutations in differentiated neurons are still largely unknown. Here, we investigated the physiological roles of TDP-43 and the effects of missense mutations associated with diseases in differentiated cortical neurons. The reduction of TDP-43 by siRNA increased abnormal neurites and decreased cell viability. ALS/FTLD-associated missense mutant proteins (A315T, Q331K, and M337V) were partially mislocalized to the cytosol and neurites when compared to wild-type and showed abnormal neurites similar to those observed in cases of loss of TDP-43. Interestingly, cytosolic expression of wild-type TDP-43 with mutated nuclear localization signals also induced abnormal neurtie morphology and reduction of cell viability. However, there was no significant difference in the effects of cytosolic expression in neuronal morphology and cell toxicity between wild-type and missense mutant proteins. Thus, our results suggest that mislocalization of missense mutant TDP-43 may contribute to loss of TDP-43 function and affect neuronal morphology, probably via dominant negative action before severe neurodegeneration in differentiated cortical neurons. Highlights: • The function of nuclear TDP-43 in neurite morphology in mature neurons. • Partial mislocalization of TDP-43 missense mutants into cytosol from nucleus. • Abnormal neurite morphology caused by missense mutants of TDP-43. • The effect of cytosolic expression of TDP-43 in neurite morphology and in cell survival

  12. SHP2 regulates chondrocyte terminal differentiation, growth plate architecture and skeletal cell fates.

    Directory of Open Access Journals (Sweden)

    Margot E Bowen

    Full Text Available Loss of PTPN11/SHP2 in mice or in human metachondromatosis (MC patients causes benign cartilage tumors on the bone surface (exostoses and within bones (enchondromas. To elucidate the mechanisms underlying cartilage tumor formation, we investigated the role of SHP2 in the specification, maturation and organization of chondrocytes. Firstly, we studied chondrocyte maturation by performing RNA-seq on primary chondrocyte pellet cultures. We found that SHP2 depletion, or inhibition of the ERK1/2 pathway, delays the terminal differentiation of chondrocytes from the early-hypertrophic to the late-hypertrophic stage. Secondly, we studied chondrocyte maturation and organization in mice with a mosaic postnatal inactivation of Ptpn11 in chondrocytes. We found that the vertebral growth plates of these mice have expanded domains of early-hypertrophic chondrocytes that have not yet terminally differentiated, and their enchondroma-like lesions arise from chondrocytes displaced from the growth plate due to a disruption in the organization of maturation and ossification zones. Furthermore, we observed that lesions from human MC patients also display disorganized chondrocyte maturation zones. Next, we found that inactivation of Ptpn11 in Fsp1-Cre-expressing fibroblasts induces exostosis-like outgrowths, suggesting that loss of SHP2 in cells on the bone surface and at bone-ligament attachment sites induces ectopic chondrogenesis. Finally, we performed lineage tracing to show that exostoses and enchondromas in mice likely contain mixtures of wild-type and SHP2-deficient chondrocytes. Together, these data indicate that in patients with MC, who are heterozygous for inherited PTPN11 loss-of-function mutations, second-hit mutations in PTPN11 can induce enchondromas by disrupting the organization and delaying the terminal differentiation of growth plate chondrocytes, and can induce exostoses by causing ectopic chondrogenesis of cells on the bone surface. Furthermore, the

  13. Retinoic acid differentially regulates the migration of innate lymphoid cell subsets to the gut

    OpenAIRE

    Kim, Myung H.; Taparowsky, Elizabeth J.; Kim, Chang H.

    2015-01-01

    Distinct groups of innate lymphoid cells (ILCs) such as ILC1, ILC2 and ILC3 populate the intestine, but how these ILCs develop tissue tropism for this organ is unclear. We report that prior to migration to the intestine ILCs first undergo a `switch' in their expression of homing receptors from lymphoid to gut homing receptors. This process is regulated by mucosal dendritic cells and the gut-specific tissue factor retinoic acid (RA). This change in homing receptors is required for long-term po...

  14. Uhrf1 controls the self-renewal versus differentiation of hematopoietic stem cells by epigenetically regulating the cell-division modes.

    Science.gov (United States)

    Zhao, Jingyao; Chen, Xufeng; Song, Guangrong; Zhang, Jiali; Liu, Haifeng; Liu, Xiaolong

    2017-01-10

    Hematopoietic stem cells (HSCs) are able to both self-renew and differentiate. However, how individual HSC makes the decision between self-renewal and differentiation remains largely unknown. Here we report that ablation of the key epigenetic regulator Uhrf1 in the hematopoietic system depletes the HSC pool, leading to hematopoietic failure and lethality. Uhrf1-deficient HSCs display normal survival and proliferation, yet undergo erythroid-biased differentiation at the expense of self-renewal capacity. Notably, Uhrf1 is required for the establishment of DNA methylation patterns of erythroid-specific genes during HSC division. The expression of these genes is enhanced in the absence of Uhrf1, which disrupts the HSC-division modes by promoting the symmetric differentiation and suppressing the symmetric self-renewal. Moreover, overexpression of one of the up-regulated genes, Gata1, in HSCs is sufficient to phenocopy Uhrf1-deficient HSCs, which show impaired HSC symmetric self-renewal and increased differentiation commitment. Taken together, our findings suggest that Uhrf1 controls the self-renewal versus differentiation of HSC through epigenetically regulating the cell-division modes, thus providing unique insights into the relationship among Uhrf1-mediated DNA methylation, cell-division mode, and HSC fate decision.

  15. Angiotensin II Regulates Th1 T Cell Differentiation Through Angiotensin II Type 1 Receptor-PKA-Mediated Activation of Proteasome.

    Science.gov (United States)

    Qin, Xian-Yun; Zhang, Yun-Long; Chi, Ya-Fei; Yan, Bo; Zeng, Xiang-Jun; Li, Hui-Hua; Liu, Ying

    2018-01-01

    Naive CD4+ T cells differentiate into T helper cells (Th1 and Th2) that play an essential role in the cardiovascular diseases. However, the molecular mechanism by which angiotensin II (Ang II) promotes Th1 differentiation remains unclear. The aim of this study was to determine whether the Ang II-induced Th1 differentiation regulated by ubiquitin-proteasome system (UPS). Jurkat cells were treated with Ang II (100 nM) in the presence or absence of different inhibitors. The gene mRNA levels were detected by real-time quantitative PCR analysis. The protein levels were measured by ELISA assay or Western blot analysis, respectively. Ang II treatment significantly induced a shift from Th0 to Th1 cell differentiation, which was markedly blocked by angiotensin II type 1 receptor (AT1R) inhibitor Losartan (LST). Moreover, Ang II significantly increased the activities and the expression of proteasome catalytic subunits (β1, β1i, β2i and β5i) in a dose- and time-dependent manner. However, Ang II-induced proteasome activities were remarkably abrogated by LST and PKA inhibitor H-89. Mechanistically, Ang II-induced Th1 differentiation was at least in part through proteasome-mediated degradation of IκBα and MKP-1 and activation of STAT1 and NF-κB. This study for the first time demonstrates that Ang II activates AT1R-PKA-proteasome pathway, which promotes degradation of IκBα and MKP-1 and activation of STAT1 and NF-κB thereby leading to Th1 differentiation. Thus, inhibition of proteasome activation might be a potential therapeutic target for Th1-mediated diseases. © 2018 The Author(s). Published by S. Karger AG, Basel.

  16. A genome-wide RNAi screen reveals MAP kinase phosphatases as key ERK pathway regulators during embryonic stem cell differentiation.

    Directory of Open Access Journals (Sweden)

    Shen-Hsi Yang

    Full Text Available Embryonic stem cells and induced pluripotent stem cells represent potentially important therapeutic agents in regenerative medicine. Complex interlinked transcriptional and signaling networks control the fate of these cells towards maintenance of pluripotency or differentiation. In this study we have focused on how mouse embryonic stem cells begin to differentiate and lose pluripotency and, in particular, the role that the ERK MAP kinase and GSK3 signaling pathways play in this process. Through a genome-wide siRNA screen we have identified more than 400 genes involved in loss of pluripotency and promoting the onset of differentiation. These genes were functionally associated with the ERK and/or GSK3 pathways, providing an important resource for studying the roles of these pathways in controlling escape from the pluripotent ground state. More detailed analysis identified MAP kinase phosphatases as a focal point of regulation and demonstrated an important role for these enzymes in controlling ERK activation kinetics and subsequently determining early embryonic stem cell fate decisions.

  17. miR-342-5p Regulates Neural Stem Cell Proliferation and Differentiation Downstream to Notch Signaling in Mice

    Directory of Open Access Journals (Sweden)

    Fang Gao

    2017-04-01

    Full Text Available Summary: Notch signaling is critically involved in neural development, but the downstream effectors remain incompletely understood. In this study, we cultured neurospheres from Nestin-Cre-mediated conditional Rbp-j knockout (Rbp-j cKO and control embryos and compared their miRNA expression profiles using microarray. Among differentially expressed miRNAs, miR-342-5p showed upregulated expression as Notch signaling was genetically or pharmaceutically interrupted. Consistently, the promoter of the miR-342-5p host gene, the Ena-vasodilator stimulated phosphoprotein-like (Evl, was negatively regulated by Notch signaling, probably through HES5. Transfection of miR-342-5p promoted the differentiation of neural stem cells (NSCs into intermediate neural progenitors (INPs in vitro and reduced the stemness of NSCs in vivo. Furthermore, miR-342-5p inhibited the differentiation of neural stem/intermediate progenitor cells into astrocytes, likely mediated by targeting GFAP directly. Our results indicated that miR-342-5p could function as a downstream effector of Notch signaling to regulate the differentiation of NSCs into INPs and astrocytes commitment. : In this article, Han and colleagues show that miR-342-5p acts as a downstream effector of Notch signaling in the mouse CNS. Notch signal inhibits miR-342-5p expression by regulating its host gene Evl. And with attenuated Notch signal in NSCs, miR-342-5p is upregulated to promote NSCs transition into INPs, and to inhibit astrocyte commitment by targeting GFAP. Keywords: neural stem cells, intermediate neural progenitors, Notch, RBP-J, neuron, glia, miR-342-5p

  18. Differential Top10 promoter regulation by six tetracycline analogues in plant cells

    Science.gov (United States)

    Love, John; Allen, George C.; Gatz, Christiane; Thompson, William F.; Brown, C. S. (Principal Investigator)

    2002-01-01

    The effects of five tetracycline analogues, anhydrotetracycline, doxycycline, minocycline, oxytetracycline, and tetracycline, on Top10 promoter activity in NT1 tobacco tissue culture cells have been analysed. The concentration that repressed Top10 promoter activity, the level of transgene repression and the kinetics of transgene de-repression were determined for each analogue, and could not be predicted from in vitro binding affinity to the tetracycline repressor or from comparison with animal cells. Doxycycline had the most potent effect on the Top10 promoter and completely inhibited transgene expression at 4 nmol l(-1). Tetracycline was the most versatile of the analogues tested; tetracycline inhibited the Top10 promoter at 10 nmol l(-1) and was easily washed out to restore Top10-driven expression in 12-24 h. A study was also made of the suitability for plant research of a novel tetracycline analogue, GR33076X. In animal cells, GR33076X de-repressed Top10 promoter activity in the presence of inhibitory concentrations of anhydrotetracycline. In NT1, it is shown that GR 33076X can antagonize repression of the Top10 promoter in the presence of tetracycline, but not of anhydrotetracycline or of doxycycline. Different tetracycline analogues can therefore be used to regulate the Top10 promoter in plant cells and this property may be exploited in planning an optimum course of transgene regulation.

  19. Retinol dehydrogenase-10 regulates pancreas organogenesis and endocrine cell differentiation via paracrine retinoic acid signalling

    DEFF Research Database (Denmark)

    Arregi, Igor; Climent, Maria; Iliev, Dobromir

    2016-01-01

    Vitamin A-derived retinoic acid (RA) signals are critical for the development of several organs, including the pancreas. However, the tissue-specific control of RA synthesis in organ and cell lineage development has only poorly been addressed in vivo. Here we show that Retinol dehydrogenase-10 (Rdh......10), a key enzyme in embryonic RA production, has important functions in pancreas organogenesis and endocrine cell differentiation. Rdh10 was expressed in the developing pancreas epithelium and surrounding mesenchyme. Rdh10 null mutant mouse embryos exhibited dorsal pancreas agenesis...... and a hypoplastic ventral pancreas with retarded tubulogenesis and branching. Conditional disruption of Rdh10 from the endoderm caused increased mortality, reduced body weight and lowered blood glucose levels after birth. Endodermal Rdh10 deficiency led to a smaller dorsal pancreas with a reduced density of early...

  20. Retinoic Acid Differentially Regulates the Migration of Innate Lymphoid Cell Subsets to the Gut.

    Science.gov (United States)

    Kim, Myung H; Taparowsky, Elizabeth J; Kim, Chang H

    2015-07-21

    Distinct groups of innate lymphoid cells (ILCs) such as ILC1, ILC2, and ILC3 populate the intestine, but how these ILCs develop tissue tropism for this organ is unclear. We report that prior to migration to the intestine ILCs first undergo a "switch" in their expression of homing receptors from lymphoid to gut homing receptors. This process is regulated by mucosal dendritic cells and the gut-specific tissue factor retinoic acid (RA). This change in homing receptors is required for long-term population and effector function of ILCs in the intestine. Only ILC1 and ILC3, but not ILC2, undergo the RA-dependent homing receptor switch in gut-associated lymphoid tissues. In contrast, ILC2 acquire gut homing receptors in a largely RA-independent manner during their development in the bone marrow and can migrate directly to the intestine. Thus, distinct programs regulate the migration of ILC subsets to the intestine for regulation of innate immunity. Copyright © 2015 Elsevier Inc. All rights reserved.

  1. 1α,25(OH)2D3 differentially regulates miRNA expression in human bladder cancer cells.

    Science.gov (United States)

    Ma, Yingyu; Hu, Qiang; Luo, Wei; Pratt, Rachel N; Glenn, Sean T; Liu, Song; Trump, Donald L; Johnson, Candace S

    2015-04-01

    Bladder cancer is the fourth most commonly diagnosed cancer in men and eighth leading cause of cancer-related death in the US. Epidemiological and experimental studies strongly suggest a role for 1α,25(OH)2D3 in cancer prevention and treatment. The antitumor activities of 1α,25(OH)2D3 are mediated by the induction of cell cycle arrest, apoptosis, differentiation and the inhibition of angiogenesis and metastasis. miRNAs play important regulatory roles in cancer development and progression. However, the role of 1α,25(OH)2D3 in the regulation of miRNA expression and the potential impact in bladder cancer has not been investigated. Therefore, we studied 1α,25(OH)2D3-regulated miRNA expression profiles in human bladder cancer cell line 253J and the highly tumorigenic and metastatic derivative line 253J-BV by miRNA qPCR panels. 253J and 253J-BV cells express endogenous vitamin D receptor (VDR), which can be further induced by 1α,25(OH)2D3. VDR target gene 24-hydroxylase was induced by 1α,25(OH)2D3 in both cell lines, indicating functional 1α,25(OH)2D3 signaling. The miRNA qPCR panel assay results showed that 253J and 253J-BV cells have distinct miRNA expression profiles. Further, 1α,25(OH)2D3 differentially regulated miRNA expression profiles in 253J and 253J-BV cells in a dynamic manner. Pathway analysis of the miRNA target genes revealed distinct patterns of contribution to the molecular functions and biological processes in the two cell lines. In conclusion, 1α,25(OH)2D3 differentially regulates the expression of miRNAs, which may contribute to distinct biological functions, in human bladder 253J and 253J-BV cells. This article is part of a Special Issue entitled '17th Vitamin D Workshop'. Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. Fragile x mental retardation protein regulates proliferation and differentiation of adult neural stem/progenitor cells.

    Directory of Open Access Journals (Sweden)

    Yuping Luo

    2010-04-01

    Full Text Available Fragile X syndrome (FXS, the most common form of inherited mental retardation, is caused by the loss of functional fragile X mental retardation protein (FMRP. FMRP is an RNA-binding protein that can regulate the translation of specific mRNAs. Adult neurogenesis, a process considered important for neuroplasticity and memory, is regulated at multiple molecular levels. In this study, we investigated whether Fmrp deficiency affects adult neurogenesis. We show that in a mouse model of fragile X syndrome, adult neurogenesis is indeed altered. The loss of Fmrp increases the proliferation and alters the fate specification of adult neural progenitor/stem cells (aNPCs. We demonstrate that Fmrp regulates the protein expression of several components critical for aNPC function, including CDK4 and GSK3beta. Dysregulation of GSK3beta led to reduced Wnt signaling pathway activity, which altered the expression of neurogenin1 and the fate specification of aNPCs. These data unveil a novel regulatory role for Fmrp and translational regulation in adult neurogenesis.

  3. miR-96 regulates the progression of differentiation in mammalian cochlear inner and outer hair cells.

    Science.gov (United States)

    Kuhn, Stephanie; Johnson, Stuart L; Furness, David N; Chen, Jing; Ingham, Neil; Hilton, Jennifer M; Steffes, Georg; Lewis, Morag A; Zampini, Valeria; Hackney, Carole M; Masetto, Sergio; Holley, Matthew C; Steel, Karen P; Marcotti, Walter

    2011-02-08

    MicroRNAs (miRNAs) are small noncoding RNAs able to regulate a broad range of protein-coding genes involved in many biological processes. miR-96 is a sensory organ-specific miRNA expressed in the mammalian cochlea during development. Mutations in miR-96 cause nonsyndromic progressive hearing loss in humans and mice. The mouse mutant diminuendo has a single base change in the seed region of the Mir96 gene leading to widespread changes in the expression of many genes. We have used this mutant to explore the role of miR-96 in the maturation of the auditory organ. We found that the physiological development of mutant sensory hair cells is arrested at around the day of birth, before their biophysical differentiation into inner and outer hair cells. Moreover, maturation of the hair cell stereocilia bundle and remodelling of auditory nerve connections within the cochlea fail to occur in miR-96 mutants. We conclude that miR-96 regulates the progression of the physiological and morphological differentiation of cochlear hair cells and, as such, coordinates one of the most distinctive functional refinements of the mammalian auditory system.

  4. MicroRNA-130b targets Fmr1 and regulates embryonic neural progenitor cell proliferation and differentiation

    International Nuclear Information System (INIS)

    Gong, Xi; Zhang, Kunshan; Wang, Yanlu; Wang, Junbang; Cui, Yaru; Li, Siguang; Luo, Yuping

    2013-01-01

    Highlights: •We found that the 3′ UTR of the Fmr1 mRNA is a target of miR-130b. •MiR-130b suppresses the expression of Fmr1 in mouse embryonic stem cell. •MiR-130b alters the proliferation of mouse embryonic stem cell. •MiR-130b alters fate specification of mouse embryonic stem cell. -- Abstract: Fragile X syndrome, one of the most common forms of inherited mental retardation, is caused by expansion of the CGG repeat in the 5′-untranslated region of the X-linked Fmr1 gene, which results in transcriptional silencing and loss of expression of its encoded protein FMRP. The loss of FMRP increases proliferation and alters fate specification in adult neural progenitor cells (aNPCs). However, little is known about Fmr1 mRNA regulation at the transcriptional and post-transcriptional levels. In the present study, we report that miR-130b regulated Fmr1 expression by directly targeting its 3′-untranslated region (3′ UTR). Up-regulation of miR-130b in mouse embryonic neural progenitor cells (eNPCs) decreased Fmr1 expression, markedly increased eNPC proliferation and altered the differentiation tendency of eNPCs, suggesting that antagonizing miR-130b may be a new therapeutic entry point for treating Fragile X syndrome

  5. MicroRNA-130b targets Fmr1 and regulates embryonic neural progenitor cell proliferation and differentiation

    Energy Technology Data Exchange (ETDEWEB)

    Gong, Xi [State Key Laboratory of Food Science and Technology, College of Life Sciences and Food Engineering, Nanchang University, Nanchang 330047 (China); Zhang, Kunshan [Department of Regenerative Medicine, Stem Cell Center, Tongji University School of Medicine, Shanghai 200092 (China); Wang, Yanlu; Wang, Junbang; Cui, Yaru [State Key Laboratory of Food Science and Technology, College of Life Sciences and Food Engineering, Nanchang University, Nanchang 330047 (China); Li, Siguang, E-mail: siguangli@163.com [Department of Regenerative Medicine, Stem Cell Center, Tongji University School of Medicine, Shanghai 200092 (China); Luo, Yuping, E-mail: luoyuping@163.com [State Key Laboratory of Food Science and Technology, College of Life Sciences and Food Engineering, Nanchang University, Nanchang 330047 (China)

    2013-10-04

    Highlights: •We found that the 3′ UTR of the Fmr1 mRNA is a target of miR-130b. •MiR-130b suppresses the expression of Fmr1 in mouse embryonic stem cell. •MiR-130b alters the proliferation of mouse embryonic stem cell. •MiR-130b alters fate specification of mouse embryonic stem cell. -- Abstract: Fragile X syndrome, one of the most common forms of inherited mental retardation, is caused by expansion of the CGG repeat in the 5′-untranslated region of the X-linked Fmr1 gene, which results in transcriptional silencing and loss of expression of its encoded protein FMRP. The loss of FMRP increases proliferation and alters fate specification in adult neural progenitor cells (aNPCs). However, little is known about Fmr1 mRNA regulation at the transcriptional and post-transcriptional levels. In the present study, we report that miR-130b regulated Fmr1 expression by directly targeting its 3′-untranslated region (3′ UTR). Up-regulation of miR-130b in mouse embryonic neural progenitor cells (eNPCs) decreased Fmr1 expression, markedly increased eNPC proliferation and altered the differentiation tendency of eNPCs, suggesting that antagonizing miR-130b may be a new therapeutic entry point for treating Fragile X syndrome.

  6. [PRODUCT OF THE BMI1--A KEY COMPONENT OF POLYCOMB--POSITIVELY REGULATES ADIPOCYTE DIFFERENTIATION OF MOUSE MESENCHYMAL STEM CELLS].

    Science.gov (United States)

    Petrov, N S; Vereschagina, N A; Sushilova, E N; Kropotov, A V; Miheeva, N F; Popov, B V

    2016-01-01

    Bmil is a key component of Polycomb (PcG), which in mammals controls the basic functions of mammalian somatic stem cells (SSC) such as self-renewal and differentiation. Bmi1 supports SSC via transcriptional suppression of genes associated with cell cycle and differentiation. The most studied target genes of Bmi1 are the genes of Ink4 locus, CdkI p16(Ink4a) and p1(Arf), suppression of which due to activating mutations of the BMI1 results in formation of cancer stem cells (CSC) and carcinomas in various tissues. In contrast, inactivation of BMI1 results in cell cycle arrest and cell senescence. Although clinical phenomena of hypo- and hyperactivation of BMI1 are well known, its targets and mechanisms of regulation of tissue specific SSC are still obscure. The goal of this study was to evaluate the regulatory role of BMI1 in adipocyte differentiation (AD) of mouse mesenchymal stem cells (MSC). Induction of AD in mouse MSC of the C3H10T1/2 cell line was associated with an increase in the expression levels of BMI1, the genes of pRb family (RB, p130) and demethylase UTX, but not methyltransferase EZH2, whose products regulate the methylation levels of H3K27. It was observed earlier that H3K27me3 may play the role of the epigenetic switch by promoting AD of human MSC via activating expression of the PPARγ2, the master gene of AD (Hemming et al., 2014). Here we show that inactivation of BMI1 using specific siRNA slows and decreases the levels of AD, but does not abolish it. This is associated with a complete inhibition of the expression of adipogenic marker genes--PPARγ2, ADIPOQ and a decrease in the expression of RB, p130, but not UTX. The results obtained give evidence that the epigenetic mechanism regulating AD differentiation in mouse and human MSC is different.

  7. Monocytic and granulocytic myeloid derived suppressor cells differentially regulate spatiotemporal tumour plasticity during metastatic cascade.

    Science.gov (United States)

    Ouzounova, Maria; Lee, Eunmi; Piranlioglu, Raziye; El Andaloussi, Abdeljabar; Kolhe, Ravindra; Demirci, Mehmet F; Marasco, Daniela; Asm, Iskander; Chadli, Ahmed; Hassan, Khaled A; Thangaraju, Muthusamy; Zhou, Gang; Arbab, Ali S; Cowell, John K; Korkaya, Hasan

    2017-04-06

    It is widely accepted that dynamic and reversible tumour cell plasticity is required for metastasis, however, in vivo steps and molecular mechanisms are poorly elucidated. We demonstrate here that monocytic (mMDSC) and granulocytic (gMDSC) subsets of myeloid-derived suppressor cells infiltrate in the primary tumour and distant organs with different time kinetics and regulate spatiotemporal tumour plasticity. Using co-culture experiments and mouse transcriptome analyses in syngeneic mouse models, we provide evidence that tumour-infiltrated mMDSCs facilitate tumour cell dissemination from the primary site by inducing EMT/CSC phenotype. In contrast, pulmonary gMDSC infiltrates support the metastatic growth by reverting EMT/CSC phenotype and promoting tumour cell proliferation. Furthermore, lung-derived gMDSCs isolated from tumour-bearing animals enhance metastatic growth of already disseminated tumour cells. MDSC-induced 'metastatic gene signature' derived from murine syngeneic model predicts poor patient survival in the majority of human solid tumours. Thus spatiotemporal MDSC infiltration may have clinical implications in tumour progression.

  8. Mof-associated complexes have overlapping and unique roles in regulating pluripotency in embryonic stem cells and during differentiation

    Science.gov (United States)

    Ravens, Sarina; Fournier, Marjorie; Ye, Tao; Stierle, Matthieu; Dembele, Doulaye; Chavant, Virginie; Tora, Làszlò

    2014-01-01

    The histone acetyltransferase (HAT) Mof is essential for mouse embryonic stem cell (mESC) pluripotency and early development. Mof is the enzymatic subunit of two different HAT complexes, MSL and NSL. The individual contribution of MSL and NSL to transcription regulation in mESCs is not well understood. Our genome-wide analysis show that i) MSL and NSL bind to specific and common sets of expressed genes, ii) NSL binds exclusively at promoters, iii) while MSL binds in gene bodies. Nsl1 regulates proliferation and cellular homeostasis of mESCs. MSL is the main HAT acetylating H4K16 in mESCs, is enriched at many mESC-specific and bivalent genes. MSL is important to keep a subset of bivalent genes silent in mESCs, while developmental genes require MSL for expression during differentiation. Thus, NSL and MSL HAT complexes differentially regulate specific sets of expressed genes in mESCs and during differentiation. DOI: http://dx.doi.org/10.7554/eLife.02104.001 PMID:24898753

  9. Retinoic acid-loaded polymeric nanoparticles enhance vascular regulation of neural stem cell survival and differentiation after ischaemia

    Science.gov (United States)

    Ferreira, R.; Fonseca, M. C.; Santos, T.; Sargento-Freitas, J.; Tjeng, R.; Paiva, F.; Castelo-Branco, M.; Ferreira, L. S.; Bernardino, L.

    2016-04-01

    Stroke is one of the leading causes of death and disability worldwide. However, current therapies only reach a small percentage of patients and may cause serious side effects. We propose the therapeutic use of retinoic acid-loaded nanoparticles (RA-NP) to safely and efficiently repair the ischaemic brain by creating a favourable pro-angiogenic environment that enhances neurogenesis and neuronal restitution. Our data showed that RA-NP enhanced endothelial cell proliferation and tubule network formation and protected against ischaemia-induced death. To evaluate the effect of RA-NP on vascular regulation of neural stem cell (NSC) survival and differentiation, endothelial cell-conditioned media (EC-CM) were collected. EC-CM from healthy RA-NP-treated cells reduced NSC death and promoted proliferation while EC-CM from ischaemic RA-NP-treated cells decreased cell death, increased proliferation and neuronal differentiation. In parallel, human endothelial progenitor cells (hEPC), which are part of the endogenous repair response to vascular injury, were collected from ischaemic stroke patients. hEPC treated with RA-NP had significantly higher proliferation, which further highlights the therapeutic potential of this formulation. To conclude, RA-NP protected endothelial cells from ischaemic death and stimulated the release of pro-survival, proliferation-stimulating factors and differentiation cues for NSC. RA-NP were shown to be up to 83-fold more efficient than free RA and to enhance hEPC proliferation. These data serve as a stepping stone to use RA-NP as vasculotrophic and neurogenic agents for vascular disorders and neurodegenerative diseases with compromised vasculature.

  10. Differential regulation of glutathione peroxidase by selenomethionine and hyperoxia in endothelial cells.

    Science.gov (United States)

    Jornot, L; Junod, A F

    1995-01-01

    We have studied the effect of selenomethionine (SeMet) and hyperoxia on the expression of glutathione peroxidase (GP) in human umbilical vein endothelial cells. Incubation of HUVEC with 1 x 10(-6) M SeMet for 24 h and 48 h caused a 65% and 86% increase in GP activity respectively. The same treatment did not result in significant changes in GP gene transcription and mRNA levels. Pactamycin, a specific inhibitor of the initiation step of translation, prevented the rise in GP activity induced by SeMet and caused an increase in GP mRNA in both cells grown in normal and SeMet-supplemented medium. Interestingly, SeMet supplementation stimulated the recruitment of GP mRNA from an untranslatable pool on to polyribosomes, so that the concentration of GP mRNA in polyribosomal translatable pools was 50% higher in cells grown in SeMet-supplemented medium than in cells grown in normal medium. On the other hand, cells exposed to 95% O2 for 3 days in normal medium showed a 60%, 394% and 81% increase in GP gene transcription rate, mRNA levels and activity respectively. Hyperoxia also stabilized GP mRNA. Hyperoxic cells grown in SeMet-supplemented medium did not show any change in GP gene transcription and mRNA levels, but expressed an 81% and 100% increase in GP activity and amount of GP mRNA associated with polyribosomes respectively, when compared with hyperoxic cells maintained in normal medium. Thus, GP appeared to be regulated post-transcriptionally, most probably co-translationally, in response to selenium availability, and transcriptionally and post-transcriptionally in response to oxygen. Images Figure 1 Figure 2 Figure 4 Figure 7 Figure 8 PMID:7887914

  11. Coordinated Proliferation and Differentiation of Human-Induced Pluripotent Stem Cell-Derived Cardiac Progenitor Cells Depend on Bone Morphogenetic Protein Signaling Regulation by GREMLIN 2.

    Science.gov (United States)

    Bylund, Jeffery B; Trinh, Linh T; Awgulewitsch, Cassandra P; Paik, David T; Jetter, Christopher; Jha, Rajneesh; Zhang, Jianhua; Nolan, Kristof; Xu, Chunhui; Thompson, Thomas B; Kamp, Timothy J; Hatzopoulos, Antonis K

    2017-05-01

    Heart development depends on coordinated proliferation and differentiation of cardiac progenitor cells (CPCs), but how the two processes are synchronized is not well understood. Here, we show that the secreted Bone Morphogenetic Protein (BMP) antagonist GREMLIN 2 (GREM2) is induced in CPCs shortly after cardiac mesoderm specification during differentiation of human pluripotent stem cells. GREM2 expression follows cardiac lineage differentiation independently of the differentiation method used, or the origin of the pluripotent stem cells, suggesting that GREM2 is linked to cardiogenesis. Addition of GREM2 protein strongly increases cardiomyocyte output compared to established procardiogenic differentiation methods. Our data show that inhibition of canonical BMP signaling by GREM2 is necessary to promote proliferation of CPCs. However, canonical BMP signaling inhibition alone is not sufficient to induce cardiac differentiation, which depends on subsequent JNK pathway activation specifically by GREM2. These findings may have broader implications in the design of approaches to orchestrate growth and differentiation of pluripotent stem cell-derived lineages that depend on precise regulation of BMP signaling.

  12. Coordinated Proliferation and Differentiation of Human-Induced Pluripotent Stem Cell-Derived Cardiac Progenitor Cells Depend on Bone Morphogenetic Protein Signaling Regulation by GREMLIN 2

    Science.gov (United States)

    Bylund, Jeffery B.; Trinh, Linh T.; Awgulewitsch, Cassandra P.; Paik, David T.; Jetter, Christopher; Jha, Rajneesh; Zhang, Jianhua; Nolan, Kristof; Xu, Chunhui; Thompson, Thomas B.; Kamp, Timothy J.

    2017-01-01

    Heart development depends on coordinated proliferation and differentiation of cardiac progenitor cells (CPCs), but how the two processes are synchronized is not well understood. Here, we show that the secreted Bone Morphogenetic Protein (BMP) antagonist GREMLIN 2 (GREM2) is induced in CPCs shortly after cardiac mesoderm specification during differentiation of human pluripotent stem cells. GREM2 expression follows cardiac lineage differentiation independently of the differentiation method used, or the origin of the pluripotent stem cells, suggesting that GREM2 is linked to cardiogenesis. Addition of GREM2 protein strongly increases cardiomyocyte output compared to established procardiogenic differentiation methods. Our data show that inhibition of canonical BMP signaling by GREM2 is necessary to promote proliferation of CPCs. However, canonical BMP signaling inhibition alone is not sufficient to induce cardiac differentiation, which depends on subsequent JNK pathway activation specifically by GREM2. These findings may have broader implications in the design of approaches to orchestrate growth and differentiation of pluripotent stem cell-derived lineages that depend on precise regulation of BMP signaling. PMID:28125926

  13. MicroRNAs regulate T-cell production of interleukin-9 and identify hypoxia-inducible factor-2α as an important regulator of T helper 9 and regulatory T-cell differentiation.

    Science.gov (United States)

    Singh, Yogesh; Garden, Oliver A; Lang, Florian; Cobb, Bradley S

    2016-09-01

    MicroRNAs (miRNAs) regulate many aspects of helper T cell (Th) development and function. Here we found that they are required for the suppression of interleukin-9 (IL-9) expression in Th9 cells and other Th subsets. Two highly related miRNAs (miR-15b and miR-16) that we previously found to play an important role in regulatory T (Treg) cell differentiation were capable of suppressing IL-9 expression when they were over-expressed in Th9 cells. We used these miRNAs as tools to identify novel regulators of IL-9 expression and found that they could regulate the expression of Epas1, which encodes hypoxia-inducible factor (HIF)-2α. HIF proteins regulate metabolic pathway usage that is important in determining appropriate Th differentiation. The related protein, HIF-1α enhances Th17 differentiation and inhibits Treg cell differentiation. Here we found that HIF-2α was required for IL-9 expression in Th9 cells, but its expression was not sufficient in other Th subsets. Furthermore, HIF-2α suppressed Treg cell differentiation like HIF-1α, demonstrating both similar and distinct roles of the HIF proteins in Th differentiation and adding a further dimension to their function. Ironically, even though miR-15b and miR-16 suppressed HIF-2α expression in Treg cells, inhibiting their function in Treg cells did not lead to an increase in IL-9 expression. Therefore, the physiologically relevant miRNAs that regulate IL-9 expression in Treg cells and other subsets remain unknown. Nevertheless, the analysis of miR-15b and miR-16 function led to the discovery of the importance of HIF-2α so this work demonstrated the utility of studying miRNA function to identify novel regulatory pathways in helper T-cell development. © 2016 John Wiley & Sons Ltd.

  14. MicroRNA-4739 regulates osteogenic and adipocytic differentiation of immortalized human bone marrow stromal cells via targeting LRP3

    Directory of Open Access Journals (Sweden)

    Mona Elsafadi

    2017-04-01

    Full Text Available Understanding the regulatory networks underlying lineage differentiation and fate determination of human bone marrow stromal cells (hBMSC is a prerequisite for their therapeutic use. The goal of the current study was to unravel the novel role of the low-density lipoprotein receptor-related protein 3 (LRP3 in regulating the osteogenic and adipogenic differentiation of immortalized hBMSCs. Gene expression profiling revealed significantly higher LRP3 levels in the highly osteogenic hBMSC clone imCL1 than in the less osteogenic clone imCL2, as well as a significant upregulation of LRP3 during the osteogenic induction of the imCL1 clone. Data from functional and gene expression assays demonstrated the role of LRP3 as a molecular switch promoting hBMSC lineage differentiation into osteoblasts and inhibiting differentiation into adipocytes. Interestingly, microRNA (miRNA expression profiling identified miR-4739 as the most under-represented miRNA (−36.11 fold in imCL1 compared to imCL2. The TargetScan prediction algorithm, combined with functional and biochemical assays, identified LRP3 mRNA as a novel target of miR-4739, with a single potential binding site for miR-4739 located in the LRP3 3′ UTR. Regulation of LRP3 expression by miR-4739 was subsequently confirmed by qRT-PCR, western blotting, and luciferase assays. Over-expression of miR-4739 mimicked the effects of LRP3 knockdown on promoting adipogenic and suppressing osteogenic differentiation of hBMSCs. Hence, we report for the first time a novel biological role for the LRP3/hsa-miR-4739 axis in balancing osteogenic and adipocytic differentiation of hBMSCs. Our data support the potential utilization of miRNA-based therapies in regenerative medicine.

  15. p53 regulates the proliferation, differentiation and spontaneous transformation of mesenchymal stem cells

    Energy Technology Data Exchange (ETDEWEB)

    Armesilla-Diaz, Alejandro, E-mail: aarmesilla@cib.csic.es [Department of Cellular and Molecular Physiopathology, Centro de Investigaciones Biologicas, CSIC, Ramiro de Maeztu, 9, 28040 Madrid (Spain); Elvira, Gema; Silva, Augusto [Department of Cellular and Molecular Physiopathology, Centro de Investigaciones Biologicas, CSIC, Ramiro de Maeztu, 9, 28040 Madrid (Spain)

    2009-12-10

    Mesenchymal stem cells (MSC) have been extensively studied and gained wide popularity due to their therapeutic potential. Spontaneous transformation of MSC, from both human and murine origin, has been reported in many studies. MSC transformation depends on the culture conditions, the origin of the cells and the time on culture; however, the precise biological characteristics involved in this process have not been fully defined yet. In this study, we investigated the role of p53 in the biology and transformation of murine bone marrow (BM)-derived MSC. We demonstrate that the MSC derived from p53KO mice showed an augmented proliferation rate, a shorter doubling time and also morphologic and phenotypic changes, as compared to MSC derived from wild-type animals. Furthermore, the MSC devoid of p53 had an increased number of cells able to generate colonies. In addition, not only proliferation but also MSC differentiation is controlled by p53 since its absence modifies the speed of the process. Moreover, genomic instability, changes in the expression of c-myc and anchorage independent growth were also observed in p53KO MSC. In addition, the absence of p53 implicates the spontaneous transformation of MSC in long-term cultures. Our results reveal that p53 plays a central role in the biology of MSC.

  16. Prohibitin regulates the FSH signaling pathway in rat granulosa cell differentiation.

    Science.gov (United States)

    Chowdhury, Indrajit; Thomas, Kelwyn; Zeleznik, Anthony; Thompson, Winston E

    2016-05-01

    Published results from our laboratory identified prohibitin (PHB), a gene product expressed in granulosa cells (GCs) that progressively increases during follicle maturation. Our current in vitro studies demonstrate that follicle-stimulating hormone (FSH) stimulates Phb expression in rat primary GCs. The FSH-dependent expression of PHB was primarily localized within mitochondria, and positively correlates with the morphological changes in GCs organelles, and synthesis and secretions of estradiol (E2) and progesterone (P4). In order to confirm that PHB plays a regulatory role in rat GC differentiation, endogenous PHB-knockdown studies were carried out in undifferentiated GCs using adenoviral (Ad)-mediated RNA interference methodology. Knockdown of PHB in GCs resulted in the suppression of the key steroidogenic enzymes including steroidogenic acute regulatory protein (StAR), p450 cholesterol side-chain cleavage enzyme (p450scc), 3β-hydroxysteroid dehydrogenase (3β-HSD), and aromatase (Cyp19a1); and decreased E2 and P4 synthesis and secretions in the presence of FSH stimulation. Furthermore, these experimental studies also provided direct evidence that PHB within the mitochondrial fraction in GCs is phosphorylated at residues Y249, T258, and Y259 in response to FSH stimulation. The observed levels of phosphorylation of PHB at Y249, T258, and Y259 were significantly low in GCs in the absence of FSH stimulation. In addition, during GC differentiation FSH-induced expression of phospho-PHB (pPHB) requires the activation of MEK1-ERK1/2 signaling pathway. Taken together, these studies provide new evidence supporting FSH-dependent PHB/pPHB upregulation in GCs is required to sustain the differentiated state of GCs. © 2016 The authors.

  17. Chondroitin sulfate proteoglycans regulate the growth, differentiation and migration of multipotent neural precursor cells through the integrin signaling pathway

    Directory of Open Access Journals (Sweden)

    Lü He-Zuo

    2009-10-01

    Full Text Available Abstract Background Neural precursor cells (NPCs are defined by their ability to proliferate, self-renew, and retain the potential to differentiate into neurons and glia. Deciphering the factors that regulate their behaviors will greatly aid in their use as potential therapeutic agents or targets. Chondroitin sulfate proteoglycans (CSPGs are prominent components of the extracellular matrix (ECM in the central nervous system (CNS and are assumed to play important roles in controlling neuronal differentiation and development. Results In the present study, we demonstrated that CSPGs were constitutively expressed on the NPCs isolated from the E16 rat embryonic brain. When chondroitinase ABC was used to abolish the function of endogenous CSPGs on NPCs, it induced a series of biological responses including the proliferation, differentiation and migration of NPCs, indicating that CSPGs may play a critical role in NPC development and differentiation. Finally, we provided evidence suggesting that integrin signaling pathway may be involved in the effects of CSPGs on NPCs. Conclusion The present study investigating the influence and mechanisms of CSPGs on the differentiation and migration of NPCs should help us to understand the basic biology of NPCs during CNS development and provide new insights into developing new strategies for the treatment of the neurological disorders in the CNS.

  18. Epigenetic Library Screen Identifies Abexinostat as Novel Regulator of Adipocytic and Osteoblastic Differentiation of Human Skeletal (Mesenchymal) Stem Cells

    Science.gov (United States)

    Ali, Dalia; Hamam, Rimi; Alfayez, Musaed; Kassem, Moustapha; Aldahmash, Abdullah

    2016-01-01

    The epigenetic mechanisms promoting lineage-specific commitment of human skeletal (mesenchymal or stromal) stem cells (hMSCs) into adipocytes or osteoblasts are still not fully understood. Herein, we performed an epigenetic library functional screen and identified several novel compounds, including abexinostat, which promoted adipocytic and osteoblastic differentiation of hMSCs. Using gene expression microarrays, chromatin immunoprecipitation for H3K9Ac combined with high-throughput DNA sequencing (ChIP-seq), and bioinformatics, we identified several key genes involved in regulating stem cell proliferation and differentiation that were targeted by abexinostat. Concordantly, ChIP-quantitative polymerase chain reaction revealed marked increase in H3K9Ac epigenetic mark on the promoter region of AdipoQ, FABP4, PPARγ, KLF15, CEBPA, SP7, and ALPL in abexinostat-treated hMSCs. Pharmacological inhibition of focal adhesion kinase (PF-573228) or insulin-like growth factor-1R/insulin receptor (NVP-AEW51) signaling exhibited significant inhibition of abexinostat-mediated adipocytic differentiation, whereas inhibition of WNT (XAV939) or transforming growth factor-β (SB505124) signaling abrogated abexinostat-mediated osteogenic differentiation of hMSCs. Our findings provide insight into the understanding of the relationship between the epigenetic effect of histone deacetylase inhibitors, transcription factors, and differentiation pathways governing adipocyte and osteoblast differentiation. Manipulating such pathways allows a novel use for epigenetic compounds in hMSC-based therapies and tissue engineering. Significance This unbiased epigenetic library functional screen identified several novel compounds, including abexinostat, that promoted adipocytic and osteoblastic differentiation of human skeletal (mesenchymal or stromal) stem cells (hMSCs). These data provide new insight into the understanding of the relationship between the epigenetic effect of histone deacetylase

  19. Sox9-regulated miRNA-574-3p inhibits chondrogenic differentiation of mesenchymal stem cells.

    Directory of Open Access Journals (Sweden)

    David Guérit

    Full Text Available The aim of this study was to identify new microRNAs (miRNAs that are modulated during the differentiation of mesenchymal stem cells (MSCs toward chondrocytes. Using large scale miRNA arrays, we compared the expression of miRNAs in MSCs (day 0 and at early time points (day 0.5 and 3 after chondrogenesis induction. Transfection of premiRNA or antagomiRNA was performed on MSCs before chondrogenesis induction and expression of miRNAs and chondrocyte markers was evaluated at different time points during differentiation by RT-qPCR. Among miRNAs that were modulated during chondrogenesis, we identified miR-574-3p as an early up-regulated miRNA. We found that miR-574-3p up-regulation is mediated via direct binding of Sox9 to its promoter region and demonstrated by reporter assay that retinoid X receptor (RXRα is one gene specifically targeted by the miRNA. In vitro transfection of MSCs with premiR-574-3p resulted in the inhibition of chondrogenesis demonstrating its role during the commitment of MSCs towards chondrocytes. In vivo, however, both up- and down-regulation of miR-574-3p expression inhibited differentiation toward cartilage and bone in a model of heterotopic ossification. In conclusion, we demonstrated that Sox9-dependent up-regulation of miR-574-3p results in RXRα down-regulation. Manipulating miR-574-3p levels both in vitro and in vivo inhibited chondrogenesis suggesting that miR-574-3p might be required for chondrocyte lineage maintenance but also that of MSC multipotency.

  20. NKAP regulates iNKT cell proliferation and differentiation into ROR-��t expressing NKT17 cells

    OpenAIRE

    Thapa, Puspa; Chen, Meibo W.; McWilliams, Douglas C.; Belmonte, Paul; Constans, Megan; Sant���Angelo, Derek B.; Shapiro, Virginia Smith

    2016-01-01

    Invariant Natural Killer T (iNKT) cells are a unique lineage with characteristics of both adaptive and innate lymphocytes, and recognize glycolipid presented by an MHC Class I-like CD1d molecule. During thymic development, iNKT cells also differentiate into NKT1, NKT2 and NKT17 functional subsets that preferentially produce cytokines IFN-��, IL-4 and IL-17, respectively, upon activation. Newly selected iNKT cells undergo a burst of proliferation, which is defective in mice with a specific del...

  1. Protein kinase C is differentially regulated by thrombin, insulin, and epidermal growth factor in human mammary tumor cells

    Energy Technology Data Exchange (ETDEWEB)

    Gomez, M.L.; Tellez-Inon, M.T. (Instituto de Ingenieria Genetica y Biologia Molecular, Buenos Aires (Argentina)); Medrano, E.E.; Cafferatta, E.G.A. (Instituto de Investigaciones Bioquimicas Fundacion Campomar, Buenos Aires (Argentina))

    1988-03-01

    The exposure of serum-deprived mammary tumor cells MCF-7 and T-47D to insulin, thrombin, and epidermal growth factor (EGF) resulted in dramatic modifications in the activity and in the translocation capacity of protein kinase C from cytosol to membrane fractions. Insulin induces a 600% activation of the enzyme after 5 h of exposure to the hormone in MCF-7 cells; thrombin either activates (200% in MCF-7) or down-regulates (in T-47D), and EGF exerts only a moderate effect. Thus, the growth factors studied modulate differentially the protein kinase C activity in human mammary tumor cells. The physiological significance of the results obtained are discussed in terms of the growth response elicited by insulin, thrombin, and EGF.

  2. Gene trapping in differentiating cell lines: regulation of the lysosomal protease cathepsin B in skeletal myoblast growth and fusion.

    Science.gov (United States)

    Gogos, J A; Thompson, R; Lowry, W; Sloane, B F; Weintraub, H; Horwitz, M

    1996-08-01

    To identify genes regulated during skeletal muscle differentiation, we have infected mouse C2C12 myoblasts with retroviral gene trap vectors, containing a promoterless marker gene with a 5' splice acceptor signal. Integration of the vector adjacent to an actively transcribed gene places the marker under the transcriptional control of the endogenous gene, while the adjacent vector sequences facilitate cloning. The vector insertionally mutates the trapped locus and may also form fusion proteins with the endogenous gene product. We have screened several hundred clones, each containing a trapping vector integrated into a different endogenous gene. In agreement with previous estimates based on hybridization kinetics, we find that a large proportion of all genes expressed in myoblasts are regulated during differentiation. Many of these genes undergo unique temporal patterns of activation or repression during cell growth and myotube formation, and some show specific patterns of subcellular localization. The first gene we have identified with this strategy is the lysosomal cysteine protease cathepsin B. Expression from the trapped allele is upregulated during early myoblast fusion and downregulated in myotubes. A direct role for cathepsin B in myoblast growth and fusion is suggested by the observation that the trapped cells deficient in cathepsin B activity have an unusual morphology and reduced survival in low-serum media and undergo differentiation with impaired cellular fusion. The phenotype is reproduced by antisense cathepsin B expression in parental C2C12 myoblasts. The cellular phenotype is similar to that observed in cultured myoblasts from patients with I cell disease, in which there is diminished accumulation of lysosomal enzymes. This suggests that a specific deficiency of cathepsin B could contribute to the myopathic component of this illness.

  3. Cell Surface Trafficking of TLR1 Is Differentially Regulated by the Chaperones PRAT4A and PRAT4B*

    Science.gov (United States)

    Hart, Bryan E.; Tapping, Richard I.

    2012-01-01

    The subcellular localization of Toll-like receptors (TLRs) is critical to their ability to function as innate immune sensors of microbial infection. We previously reported that an I602S polymorphism of human TLR1 is associated with aberrant trafficking of the receptor to the cell surface, loss of responses to TLR1 agonists, and differential susceptibility to diseases caused by pathogenic mycobacteria. Through an extensive analysis of receptor deletion and point mutants we have discovered that position 602 resides within a short 6 amino acid cytoplasmic region that is required for TLR1 surface expression. This short trafficking motif, in conjunction with the adjacent transmembrane domain, is sufficient to direct TLR1 to the cell surface. A serine at position 602 interrupts this trafficking motif and prevents cell surface expression of TLR1. Additionally, we have found that ER-resident TLR chaperones, PRAT4A and PRAT4B, act as positive and negative regulators of TLR1 surface trafficking, respectively. Importantly, either over-expression of PRAT4A or knock-down of PRAT4B rescues cell surface expression of the TLR1 602S variant. We also report that IFN-γ treatment of primary human monocytes derived from homozygous 602S individuals rescues TLR1 cell surface trafficking and cellular responses to soluble agonists. This event appears to be mediated by PRAT4A whose expression is strongly induced in human monocytes by IFN-γ. Collectively, these results provide a mechanism for the differential trafficking of TLR1 I602S variants, and highlight the distinct roles for PRAT4A and PRAT4B in the regulation of TLR1 surface expression. PMID:22447933

  4. Ibandronate promotes osteogenic differentiation of periodontal ligament stem cells by regulating the expression of microRNAs

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Qiang [Department of General Dentistry and Emergency, College of Stomatology, Fourth Military Medical University, Xi' an, Shaanxi 710032 (China); Zhao, Zhi-Ning [Clinical Laboratory, 451 Hospital of Chinese PLA, Xi' an 710054 (China); Cheng, Jing-Tao [Department of Special Dentistry, College of Stomatology, Fourth Military Medical University, Xi' an, Shaanxi 710032 (China); Zhang, Bin [Department of Orthodontics, College of Stomatology, Fourth Military Medical University, Xi' an, Shaanxi 710032 (China); Xu, Jie [Department of Periodontology, College of Stomatology, Fourth Military Medical University, Xi' an, Shaanxi 710032 (China); Huang, Fei; Zhao, Rui-Ni [Department of General Dentistry and Emergency, College of Stomatology, Fourth Military Medical University, Xi' an, Shaanxi 710032 (China); Chen, Yong-Jin, E-mail: cyj1229@fmmu.edu.cn [Department of General Dentistry and Emergency, College of Stomatology, Fourth Military Medical University, Xi' an, Shaanxi 710032 (China)

    2011-01-07

    Research highlights: {yields} Ibandronate significantly promote the proliferation of PDLSC cells. {yields} Ibandronate enhanced the expression of ALP, COL-1, OPG, OCN, Runx2. {yields} The expression of a class of miRNAs, e.g., miR-18a, miR-133a, miR-141 and miR-19a, was significantly modified in PDLSC cells cultured with ibandronate. {yields} Ibandronate regulates the expression of diverse bone formation-related genes via miRNAs in PDLSCs. {yields} Ibandronate can suppress the activity of osteoclast while promoting the proliferation of osteoblast by regulating the expression of microRNAs. -- Abstract: Bisphosphonates (BPs) have a profound effect on bone resorption and are widely used to treat osteoclast-mediated bone diseases. They suppress bone resorption by inhibiting the activity of mature osteoclasts and/or the formation of new osteoclasts. Osteoblasts may be an alternative target for BPs. Periodontal ligament stem cells (PDLSCs) exhibit osteoblast-like features and are capable of differentiating into osteoblasts or cementoblasts. This study aimed to determine the effects of ibandronate, a nitrogen-containing BP, on the proliferation and the differentiation of PDLSCs and to identify the microRNAs (miRNAs) that mediate these effects. The PDLSCs were treated with ibandronate, and cell proliferation was measured using the MTT (3-dimethylthiazol-2,5-diphenyltetrazolium bromide) assay. The expression of genes and miRNAs involved in osteoblastic differentiation was assayed using quantitative real-time reverse-transcription polymerase chain reaction (qRT-PCR). Ibandronate promoted the proliferation of PDLSCs and enhanced the expression of alkaline phosphatase (ALP), type I collagen (COL-1), osteoprotegerin (OPG), osteocalcin (OCN), and Runx2. The expression of miRNAs, including miR-18a, miR-133a, miR-141 and miR-19a, was significantly altered in the PDLSCs cultured with ibandronate. In PDLSCs, ibandronate regulates the expression of diverse bone formation

  5. Ibandronate promotes osteogenic differentiation of periodontal ligament stem cells by regulating the expression of microRNAs

    International Nuclear Information System (INIS)

    Zhou, Qiang; Zhao, Zhi-Ning; Cheng, Jing-Tao; Zhang, Bin; Xu, Jie; Huang, Fei; Zhao, Rui-Ni; Chen, Yong-Jin

    2011-01-01

    Research highlights: → Ibandronate significantly promote the proliferation of PDLSC cells. → Ibandronate enhanced the expression of ALP, COL-1, OPG, OCN, Runx2. → The expression of a class of miRNAs, e.g., miR-18a, miR-133a, miR-141 and miR-19a, was significantly modified in PDLSC cells cultured with ibandronate. → Ibandronate regulates the expression of diverse bone formation-related genes via miRNAs in PDLSCs. → Ibandronate can suppress the activity of osteoclast while promoting the proliferation of osteoblast by regulating the expression of microRNAs. -- Abstract: Bisphosphonates (BPs) have a profound effect on bone resorption and are widely used to treat osteoclast-mediated bone diseases. They suppress bone resorption by inhibiting the activity of mature osteoclasts and/or the formation of new osteoclasts. Osteoblasts may be an alternative target for BPs. Periodontal ligament stem cells (PDLSCs) exhibit osteoblast-like features and are capable of differentiating into osteoblasts or cementoblasts. This study aimed to determine the effects of ibandronate, a nitrogen-containing BP, on the proliferation and the differentiation of PDLSCs and to identify the microRNAs (miRNAs) that mediate these effects. The PDLSCs were treated with ibandronate, and cell proliferation was measured using the MTT (3-dimethylthiazol-2,5-diphenyltetrazolium bromide) assay. The expression of genes and miRNAs involved in osteoblastic differentiation was assayed using quantitative real-time reverse-transcription polymerase chain reaction (qRT-PCR). Ibandronate promoted the proliferation of PDLSCs and enhanced the expression of alkaline phosphatase (ALP), type I collagen (COL-1), osteoprotegerin (OPG), osteocalcin (OCN), and Runx2. The expression of miRNAs, including miR-18a, miR-133a, miR-141 and miR-19a, was significantly altered in the PDLSCs cultured with ibandronate. In PDLSCs, ibandronate regulates the expression of diverse bone formation-related genes via miRNAs. The exact

  6. FTH1P3, a Novel H-Ferritin Pseudogene Transcriptionally Active, Is Ubiquitously Expressed and Regulated during Cell Differentiation.

    Directory of Open Access Journals (Sweden)

    Maddalena Di Sanzo

    Full Text Available Ferritin, the major iron storage protein, performs its essential functions in the cytoplasm, nucleus and mitochondria. The variable assembly of 24 subunits of the Heavy (H and Light (L type composes the cytoplasmic molecule. In humans, two distinct genes code these subunits, both belonging to complex multigene families. Until now, one H gene has been identified with the coding sequence interrupted by three introns and more than 20 intronless copies widely dispersed on different chromosomes. Two of the intronless genes are actively transcribed in a tissue-specific manner. Herein, we report that FTH1P3, another intronless pseudogene, is transcribed. FTH1P3 transcript was detected in several cell lines and tissues, suggesting that its transcription is ubiquitary, as it happens for the parental ferritin H gene. Moreover, FTH1P3 expression is positively regulated during the cell differentiation process.

  7. Identification of Wnt Pathway Target Genes Regulating the Division and Differentiation of Larval Seam Cells and Vulval Precursor Cells in Caenorhabditis elegans.

    Science.gov (United States)

    Gorrepati, Lakshmi; Krause, Michael W; Chen, Weiping; Brodigan, Thomas M; Correa-Mendez, Margarita; Eisenmann, David M

    2015-06-05

    The evolutionarily conserved Wnt/β-catenin signaling pathway plays a fundamental role during metazoan development, regulating numerous processes including cell fate specification, cell migration, and stem cell renewal. Wnt ligand binding leads to stabilization of the transcriptional effector β-catenin and upregulation of target gene expression to mediate a cellular response. During larval development of the nematode Caenorhabditis elegans, Wnt/β-catenin pathways act in fate specification of two hypodermal cell types, the ventral vulval precursor cells (VPCs) and the lateral seam cells. Because little is known about targets of the Wnt signaling pathways acting during larval VPC and seam cell differentiation, we sought to identify genes regulated by Wnt signaling in these two hypodermal cell types. We conditionally activated Wnt signaling in larval animals and performed cell type-specific "mRNA tagging" to enrich for VPC and seam cell-specific mRNAs, and then used microarray analysis to examine gene expression compared to control animals. Two hundred thirty-nine genes activated in response to Wnt signaling were identified, and we characterized 50 genes further. The majority of these genes are expressed in seam and/or vulval lineages during normal development, and reduction of function for nine genes caused defects in the proper division, fate specification, fate execution, or differentiation of seam cells and vulval cells. Therefore, the combination of these techniques was successful at identifying potential cell type-specific Wnt pathway target genes from a small number of cells and at increasing our knowledge of the specification and behavior of these C. elegans larval hypodermal cells. Copyright © 2015 Gorrepati et al.

  8. Time-resolved transcriptome and proteome landscape of human regulatory T cell (Treg) differentiation reveals novel regulators of FOXP3

    KAUST Repository

    Schmidt, Angelika

    2018-04-27

    BackgroundRegulatory T cells (Tregs) expressing the transcription factor FOXP3 are crucial mediators of self-tolerance, preventing autoimmune diseases but possibly hampering tumor rejection. Clinical manipulation of Tregs is of great interest, and first-in-man trials of Treg transfer have achieved promising outcomes. Yet, the mechanisms governing induced Treg (iTreg) differentiation and the regulation of FOXP3 are incompletely understood.ResultsTo gain a comprehensive and unbiased molecular understanding of FOXP3 induction, we performed time-series RNA sequencing (RNA-Seq) and proteomics profiling on the same samples during human iTreg differentiation. To enable the broad analysis of universal FOXP3-inducing pathways, we used five differentiation protocols in parallel. Integrative analysis of the transcriptome and proteome confirmed involvement of specific molecular processes, as well as overlap of a novel iTreg subnetwork with known Treg regulators and autoimmunity-associated genes. Importantly, we propose 37 novel molecules putatively involved in iTreg differentiation. Their relevance was validated by a targeted shRNA screen confirming a functional role in FOXP3 induction, discriminant analyses classifying iTregs accordingly, and comparable expression in an independent novel iTreg RNA-Seq dataset.ConclusionThe data generated by this novel approach facilitates understanding of the molecular mechanisms underlying iTreg generation as well as of the concomitant changes in the transcriptome and proteome. Our results provide a reference map exploitable for future discovery of markers and drug candidates governing control of Tregs, which has important implications for the treatment of cancer, autoimmune, and inflammatory diseases.

  9. Differential regulation of protease activated receptor-1 and tissue plasminogen activator expression by shear stress in vascular smooth muscle cells

    Science.gov (United States)

    Papadaki, M.; Ruef, J.; Nguyen, K. T.; Li, F.; Patterson, C.; Eskin, S. G.; McIntire, L. V.; Runge, M. S.

    1998-01-01

    Recent studies have demonstrated that vascular smooth muscle cells are responsive to changes in their local hemodynamic environment. The effects of shear stress on the expression of human protease activated receptor-1 (PAR-1) and tissue plasminogen activator (tPA) mRNA and protein were investigated in human aortic smooth muscle cells (HASMCs). Under conditions of low shear stress (5 dyn/cm2), PAR-1 mRNA expression was increased transiently at 2 hours compared with stationary control values, whereas at high shear stress (25 dyn/cm2), mRNA expression was decreased (to 29% of stationary control; Pmuscle cells, indicating that the effects of shear stress on human PAR-1 were not species-specific. Flow cytometry and ELISA techniques using rat smooth muscle cells and HASMCs, respectively, provided evidence that shear stress exerted similar effects on cell surface-associated PAR-1 and tPA protein released into the conditioned media. The decrease in PAR-1 mRNA and protein had functional consequences for HASMCs, such as inhibition of [Ca2+] mobilization in response to thrombin stimulation. These data indicate that human PAR-1 and tPA gene expression are regulated differentially by shear stress, in a pattern consistent with their putative roles in several arterial vascular pathologies.

  10. T helper 2 (Th2) cell differentiation, type 2 innate lymphoid cell (ILC2) development and regulation of interleukin-4 (IL-4) and IL-13 production.

    Science.gov (United States)

    Zhu, Jinfang

    2015-09-01

    Interleukin-4 (IL-4), IL-5 and IL-13, the signature cytokines that are produced during type 2 immune responses, are critical for protective immunity against infections of extracellular parasites and are responsible for asthma and many other allergic inflammatory diseases. Although many immune cell types within the myeloid lineage compartment including basophils, eosinophils and mast cells are capable of producing at least one of these cytokines, the production of these "type 2 immune response-related" cytokines by lymphoid lineages, CD4 T helper 2 (Th2) cells and type 2 innate lymphoid cells (ILC2s) in particular, are the central events during type 2 immune responses. In this review, I will focus on the signaling pathways and key molecules that determine the differentiation of naïve CD4 T cells into Th2 cells, and how the expression of Th2 cytokines, especially IL-4 and IL-13, is regulated in Th2 cells. The similarities and differences in the differentiation of Th2 cells, IL-4-producing T follicular helper (Tfh) cells and ILC2s as well as their relationships will also be discussed. Published by Elsevier Ltd.

  11. T helper 2 (Th2) cell differentiation, type 2 innate lymphoid cell (ILC2) development and regulation of interleukin-4 (IL-4) and IL-13 production

    Science.gov (United States)

    Zhu, Jinfang

    2015-01-01

    Interleukin-4 (IL-4), IL-5 and IL-13, the signature cytokines that are produced during type 2 immune responses, are critical for protective immunity against infections of extracellular parasites and are responsible for asthma and many other allergic inflammatory diseases. Although many immune cell types within the myeloid lineage compartment including basophils, eosinophils and mast cells are capable of producing at least one of these cytokines, the production of these “type 2 immune response-related” cytokines by lymphoid lineages, CD4 T helper 2 (Th2) cells and type 2 innate lymphoid cells (ILC2s) in particular, are the central events during type 2 immune responses. In this review, I will focus on the signaling pathways and key molecules that determine the differentiation of naïve CD4 T cells into Th2 cells, and how the expression of Th2 cytokines, especially IL-4 and IL-13, is regulated in Th2 cells. The similarities and differences in the differentiation of Th2 cells, IL-4-producing T follicular helper (Tfh) cells and ILC2s as well as their relationships will also be discussed. PMID:26044597

  12. Fine-tuning Hematopoiesis: Microenvironmental factors regulating self-renewal and differentiation of hematopoietic stem cells

    NARCIS (Netherlands)

    T.C. Luis (Tiago)

    2010-01-01

    markdownabstract__Abstract__ Hematopoietic stem cells (HSCs) have the ability to self renew and generate all lineages of blood cells. Although it is currently well established that hematopoietic stem cells (HSCs) regenerate the blood compartment, it was only in the 1960s that was introduced the

  13. Mouse Hobit is a homolog of the transcriptional repressor Blimp-1 that regulates NKT cell effector differentiation

    NARCIS (Netherlands)

    van Gisbergen, Klaas P. J. M.; Kragten, Natasja A. M.; Hertoghs, Kirsten M. L.; Wensveen, Felix M.; Jonjic, Stipan; Hamann, Jörg; Nolte, Martijn A.; van Lier, Rene A. W.

    2012-01-01

    The transcriptional repressor Blimp-1 mediates the terminal differentiation of many cell types, including T cells. Here we identified Hobit (Znf683) as a previously unrecognized homolog of Blimp-1 that was specifically expressed in mouse natural killer T cells (NKT cells). Through studies of

  14. Up-regulated microRNA-143 in cancer stem cells differentiation promotes prostate cancer cells metastasis by modulating FNDC3B expression

    International Nuclear Information System (INIS)

    Fan, Xinlan; Chen, Xu; Deng, Weixi; Zhong, Guangzheng; Cai, Qingqing; Lin, Tianxin

    2013-01-01

    Metastatic prostate cancer is a leading cause of cancer-related death in men. Cancer stem cells (CSCs) are involved in tumor progression and metastasis, including in prostate cancer. There is an obvious and urgent need for effective cancer stem cells specific therapies in metastatic prostate cancer. MicroRNAs (miRNAs) are an important class of pervasive genes that are involved in a variety of biological functions, especially in cancer. The goal of this study was to identify miRNAs involved in prostate cancer metastasis and cancer stem cells. A microarray and qRT-PCR were performed to investigate the miRNA expression profiles in PC-3 sphere cells and adherent cells. A transwell assay was used to evaluate the migration of PC-3 sphere cells and adherent cells. MiR-143 was silenced with antisense oligonucleotides in PC-3, PC-3-M and LNCaP cells. The role of miR-143 in prostate cancer metastasis was measured by wound-healing and transwell assays in vitro and bioluminescence imaging in vivo. Bioinformatics and luciferase report assays were used to identify the target of miR-143. The expression of miR-143 and the migration capability were reduced in PC-3 sphere cells and progressively increased during sphere re-adherent culture. Moreover, the down-regulation of miR-143 suppressed prostate cancer cells migration and invasion in vitro and systemically inhibited metastasis in vivo. Fibronectin type III domain containing 3B (FNDC3B), which regulates cell motility, was identified as a target of miR-143. The inhibition of miR-143 increased the expression of FNDC3B protein but not FNDC3B mRNA in vitro and vivo. These data demonstrate for the first time that miR-143 was up-regulated during the differentiation of prostate cancer stem cells and promoted prostate cancer metastasis by repressing FNDC3B expression. This sheds a new insight into the post-transcriptional regulation of cancer stem cells differentiation by miRNAs, a potential approach for the treatment of prostate cancer

  15. Proliferation and osteo/odontogenic differentiation of stem cells from apical papilla regulated by Zinc fingers and homeoboxes 2: An in vitro study.

    Science.gov (United States)

    Wan, Fang; Gao, Lifen; Lu, Yating; Ma, Hongxin; Wang, Hongxing; Liang, Xiaohong; Wang, Yan; Ma, Chunhong

    2016-01-15

    In the process of tooth root development, stem cells from the apical papilla (SCAPs) can differentiate into odontoblasts and form root dentin, however, molecules regulating SCAPs differentiation have not been elucidated. Zinc fingers and homeoboxes 2 (ZHX2) is a novel transcriptional inhibitor. It is reported to modulate the development of nerve cells, liver cells, B cells, red blood cells, and so on. However, the role of ZHX2 in tooth root development remains unclear. In this study, we explored the potential role of ZHX2 in the process of SCAPs differentiation. The results showed that overexpression of ZHX2 upregulated the expression of osteo/odontogenic related genes and ALP activity, inhibited the proliferation of SCAPs. Consistently, ZHX2 knockdown reduced SCAPs mineralization and promoted SCAPs proliferation. These results indicated that ZHX2 plays a critical role in the proliferation and osteo/odontogenic differentiation of SCAPs. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. Transgelin is a TGFβ-inducible gene that regulates osteoblastic and adipogenic differentiation of human skeletal stem cells through actin cytoskeleston organization

    DEFF Research Database (Denmark)

    Elsafadi, E; Manikandan, M; Dawud, R. A.

    2016-01-01

    Regenerative medicine is a novel approach for treating conditions in which enhanced bone regeneration is required. We identified transgelin (TAGLN), a transforming growth factor beta (TGFβ)-inducible gene, as an upregulated gene during in vitro osteoblastic and adipocytic differentiation of human......MSC by regulating cytoskeleton organization. Targeting TAGLN is a plausible approach to enrich for committed hMSC cells needed for regenerative medicine application....... bone marrow-derived stromal (skeletal) stem cells (hMSC). siRNA-mediated gene silencing of TAGLN impaired lineage differentiation into osteoblasts and adipocytes but enhanced cell proliferation. Additional functional studies revealed that TAGLN deficiency impaired hMSC cell motility and in vitro...... transwell cell migration. On the other hand, TAGLN overexpression reduced hMSC cell proliferation, but enhanced cell migration, osteoblastic and adipocytic differentiation, and in vivo bone formation. In addition, deficiency or overexpression of TAGLN in hMSC was associated with significant changes...

  17. Lysine deacetylases are produced in pancreatic beta cells and are differentially regulated by proinflammatory cytokines

    DEFF Research Database (Denmark)

    Lundh, M; Christensen, D P; Rasmussen, D N

    2010-01-01

    Cytokine-induced beta cell toxicity is abrogated by non-selective inhibitors of lysine deacetylases (KDACs). The KDAC family consists of 11 members, namely histone deacetylases HDAC1 to HDAC11, but it is not known which KDAC members play a role in cytokine-mediated beta cell death. The aim...

  18. Preferential Generation of 15-HETE-PE Induced by IL-13 Regulates Goblet Cell Differentiation in Human Airway Epithelial Cells.

    Science.gov (United States)

    Zhao, Jinming; Minami, Yoshinori; Etling, Emily; Coleman, John M; Lauder, Sarah N; Tyrrell, Victoria; Aldrovandi, Maceler; O'Donnell, Valerie; Claesson, Hans-Erik; Kagan, Valerian; Wenzel, Sally

    2017-12-01

    Type 2-associated goblet cell hyperplasia and mucus hypersecretion are well known features of asthma. 15-Lipoxygenase-1 (15LO1) is induced by the type 2 cytokine IL-13 in human airway epithelial cells (HAECs) in vitro and is increased in fresh asthmatic HAECs ex vivo. 15LO1 generates a variety of products, including 15-hydroxyeicosatetraenoic acid (15-HETE), 15-HETE-phosphatidylethanolamine (15-HETE-PE), and 13-hydroxyoctadecadienoic acid (13-HODE). In this study, we investigated the 15LO1 metabolite profile at baseline and after IL-13 treatment, as well as its influence on goblet cell differentiation in HAECs. Primary HAECs obtained from bronchial brushings of asthmatic and healthy subjects were cultured under air-liquid interface culture supplemented with arachidonic acid and linoleic acid (10 μM each) and exposed to IL-13 for 7 days. Short interfering RNA transfection and 15LO1 inhibition were applied to suppress 15LO1 expression and activity. IL-13 stimulation induced expression of 15LO1 and preferentially generated 15-HETE-PE in vitro, both of which persisted after removal of IL-13. 15LO1 inhibition (by short interfering RNA and chemical inhibitor) decreased IL-13-induced forkhead box protein A3 (FOXA3) expression and enhanced FOXA2 expression. These changes were associated with reductions in both mucin 5AC and periostin. Exogenous 15-HETE-PE stimulation (alone) recapitulated IL-13-induced FOXA3, mucin 5AC, and periostin expression. The results of this study confirm the central importance of 15LO1 and its primary product, 15-HETE-PE, for epithelial cell remodeling in HAECs.

  19. Combustible and non-combustible tobacco product preparations differentially regulate human peripheral blood mononuclear cell functions.

    Science.gov (United States)

    Arimilli, Subhashini; Damratoski, Brad E; Prasad, G L

    2013-09-01

    Natural killer (NK) cells and T cells play essential roles in innate and adaptive immune responses in protecting against microbial infections and in tumor surveillance. Although evidence suggests that smoking causes immunosuppression, there is limited information whether the use of smokeless tobacco (ST) products affects immune responses. In this study, we assessed the effects of two preparations of cigarette smoke, ST extract and nicotine on T cell and NK cell responses using Toll-like receptor-ligand stimulated human peripheral blood mononuclear cells (PBMCs). The tobacco product preparations (TPPs) tested included whole smoke conditioned media (WS-CM), total particulate matter (TPM) and a ST product preparation in complete artificial saliva (ST/CAS). The PBMCs were stimulated with polyinosinic:polycytidylic acid (poly I:C) and lipopolysaccharide (LPS). A marked reduction of the expression of intracellular IFN-γ and TNF-α was evident in NK cells and T cells treated with WS-CM and TPM. Consistently, attenuation of ligand-induced secretion of cytokines (IL-1β, IL-10, IL-12 and TNF-α) from PBMCs treated with WS-CM and TPM were observed. While the treatment with TPPs did not alter the expression of the maturation marker CD69, WS-CM and TPM inhibited the cytolytic activity of human PBMCs. Suppression of perforin by WS-CM was also detected. Although interference from the vehicle confounded the interpretation of effects of ST/CAS, some effects were evident only at high concentrations. Nicotine treatment minimally impacted expression of cytokines and cytolytic activity. Data presented herein suggests that the function of NK cells and T cells is influenced by exposure to TPPs (based on equi-nicotine units) in the following order: WS-CM>TPM>ST/CAS. These findings are consistent with the hypothesis put forward by others that chronic smoking leads to immunosuppression, an effect that may contribute to increased microbial infections and cancer incidence among smokers

  20. Dopamine receptors D3 and D5 regulate CD4(+)T-cell activation and differentiation by modulating ERK activation and cAMP production.

    Science.gov (United States)

    Franz, Dafne; Contreras, Francisco; González, Hugo; Prado, Carolina; Elgueta, Daniela; Figueroa, Claudio; Pacheco, Rodrigo

    2015-07-15

    Dopamine receptors have been described in T-cells, however their signalling pathways coupled remain unknown. Since cAMP and ERKs play key roles regulating T-cell physiology, we aim to determine whether cAMP and ERK1/2-phosphorylation are modulated by dopamine receptor 3 (D3R) and D5R, and how this modulation affects CD4(+) T-cell activation and differentiation. Our pharmacologic and genetic evidence shows that D3R-stimulation reduced cAMP levels and ERK2-phosphorylation, consequently increasing CD4(+) T-cell activation and Th1-differentiation, respectively. Moreover, D5R expression reinforced TCR-triggered ERK1/2-phosphorylation and T-cell activation. In conclusion, these findings demonstrate how D3R and D5R modulate key signalling pathways affecting CD4(+) T-cell activation and Th1-differentiation. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. Autophagic flux is highly active in early mitosis and differentially regulated throughout the cell cycle.

    Science.gov (United States)

    Li, Zhiyuan; Ji, Xinmiao; Wang, Dongmei; Liu, Juanjuan; Zhang, Xin

    2016-06-28

    Mitosis is a fast process that involves dramatic cellular remodeling and has a high energy demand. Whether autophagy is active or inactive during the early stages of mitosis in a naturally dividing cell is still debated. Here we aimed to use multiple assays to resolve this apparent discrepancy. Although the LC3 puncta number was reduced in mitosis, the four different cell lines we tested all have active autophagic flux in both interphase and mitosis. In addition, the autophagic flux was highly active in nocodazole-induced, double-thymidine synchronization released as well as naturally occurring mitosis in HeLa cells. Multiple autophagy proteins are upregulated in mitosis and the increased Beclin-1 level likely contributes to the active autophagic flux in early mitosis. It is interesting that although the autophagic flux is active throughout the cell cycle, early mitosis and S phase have relatively higher autophagic flux than G1 and late G2 phases, which might be helpful to degrade the damaged organelles and provide energy during S phase and mitosis.

  2. Peroxisome Proliferator-Activated Receptor Gamma Negatively Regulates the Differentiation of Bone Marrow-Derived Mesenchymal Stem Cells Toward Myofibroblasts in Liver Fibrogenesis

    Directory of Open Access Journals (Sweden)

    Shuangshuang Jia

    2015-11-01

    Full Text Available Background/Aims: Bone marrow-derived mesenchymal stem cells (BMSCs have been confirmed to have capacity to differentiate toward hepatic myofibroblasts, which contribute to fibrogenesis in chronic liver diseases. Peroxisome proliferator-activated receptor gamma (PPARγ, a ligand-activated transcription factor, has gained a great deal of recent attention as it is involved in fibrosis and cell differentiation. However, whether it regulates the differentiation of BMSCs toward myofibroblasts remains to be defined. Methods: Carbon tetrachloride or bile duct ligation was used to induce mouse liver fibrosis. Expressions of PPARγ, α-smooth muscle actin, collagen α1 (I and collagen α1 (III were detected by real-time RT-PCR and Western blot or immunofluorescence assay. Results: PPARγ expression was decreased in mouse fibrotic liver. In addition, PPARγ was declined during the differentiation of BMSCs toward myofibroblasts induced by transforming growth factor β1. Activation of PPARγ stimulated by natural or synthetic ligands suppressed the differentiation of BMSCs. Additionally, knock down of PPARγ by siRNA contributed to BMSC differentiation toward myofibroblasts. Furthermore, PPARγ activation by natural ligand significantly inhibited the differentiation of BMSCs toward myofibroblasts in liver fibrogenesis and alleviated liver fibrosis. Conclusions: PPARγ negatively regulates the differentiation of BMSCs toward myofibroblasts, which highlights a further mechanism implicated in the BMSC differentiation.

  3. Biophysical Regulation of Vascular Differentiation and Assembly

    CERN Document Server

    Gerecht, Sharon

    2011-01-01

    The ability to grow stem cells in the laboratory and to guide their maturation to functional cells allows us to study the underlying mechanisms that govern vasculature differentiation and assembly in health and disease. Accumulating evidence suggests that early stages of vascular growth are exquisitely tuned by biophysical cues from the microenvironment, yet the scientific understanding of such cellular environments is still in its infancy. Comprehending these processes sufficiently to manipulate them would pave the way to controlling blood vessel growth in therapeutic applications. This book assembles the works and views of experts from various disciplines to provide a unique perspective on how different aspects of its microenvironment regulate the differentiation and assembly of the vasculature. In particular, it describes recent efforts to exploit modern engineering techniques to study and manipulate various biophysical cues. Biophysical Regulation of Vascular Differentiation and Assembly provides an inter...

  4. LGR4 and LGR5 regulate hair cell differentiation in the sensory epithelium of the developing mouse cochlea

    NARCIS (Netherlands)

    Zak, Magdalena; Van Oort, Thijs; Hendriksen, Ferry G.; Garcia, Marie Isabelle; Vassart, Gilbert; Grolman, Wilko

    2016-01-01

    In the developing cochlea, Wnt/β-catenin signaling positively regulates the proliferation of precursors and promotes the formation of hair cells by up-regulating Atoh1 expression. Not much, however, is known about the regulation of Wnt/β-catenin activity in the cochlea. In multiple tissues, the

  5. Fetal human airway smooth muscle cell production of leukocyte chemoattractants is differentially regulated by fluticasone.

    Science.gov (United States)

    Pearson, Helen; Britt, Rodney D; Pabelick, Christine M; Prakash, Y S; Amrani, Yassine; Pandya, Hitesh C

    2015-12-01

    Adult human airway smooth muscle (ASM) produce cytokines involved in recruitment and survival of leukocytes within airway walls. Cytokine generation by adult ASM is glucocorticoid-sensitive. Whether developing lung ASM produces cytokines in a glucocorticoid-sensitive fashion is unknown. Cultured fetal human ASM cells stimulated with TNF-α (0-20 ng/ml) were incubated with TNF-α receptor-blocking antibodies, fluticasone (1 and 100 nm), or vehicle. Supernatants and cells were assayed for the production of CCL5, CXCL10, and CXCL8 mRNA and protein and glucocorticoid receptor phosphorylation. CCL5, CXCL10, and CXCL8 mRNA and protein production by fetal ASM cell was significantly and dose-dependently following TNF-α treatment. Cytokine mRNA and protein production were effectively blocked by TNF-α R1 and R2 receptor neutralizing antibodies but variably inhibited by fluticasone. TNF-α-induced TNF-R1 and R2 receptor mRNA expression was only partially attenuated by fluticasone. Glucocorticoid receptor phosphorylation at serine (Ser) 211 but not at Ser 226 was enhanced by fluticasone. Production of CCL5, CXCL10, and CXCL8 by fetal ASM appears to involve pathways that are both qualitatively and mechanistically distinct to those described for adult ASM. The findings imply developing ASM has potential to recruit leukocyte into airways and, therefore, of relevance to childhood airway diseases.

  6. Down-regulation of Pax6 is associated with abnormal differentiation of corneal epithelial cells in severe ocular surface diseases

    Science.gov (United States)

    Li, W; Chen, Y-T; Hayashida, Y; Blanco, G; Kheirkah, A; He, H; Chen, S-Y; Liu, C-Y; Tseng, SCG

    2010-01-01

    Pax6 is the universal master control gene for eye morphogenesis. Other than retina and lens, Pax6 also expressed in the ocular surface epithelium from early gestation until the postnatal stage, in which little is known about the function of Pax6. In this study, corneal pannus tissues from patients with ocular surface diseases such as Stevens–Johnson syndrome (SJS), chemical burn, aniridia and recurrent pterygium were investigated. Our results showed that normal ocular surface epithelial cells expressed Pax6. However, corneal pannus epithelial cells from the above patients showed a decline or absence of Pax6 expression, accompanied by a decline or absence of K12 keratin but an increase of K10 keratin and filaggrin expression. Pannus basal epithelial cells maintained nuclear p63 expression and showed activated proliferation, evidenced by positive Ki67 and K16 keratin staining. On 3T3 fibroblast feeder layers, Pax6 immunostaining was negative in clones generated from epithelial cells harvested from corneal pannus from SJS or aniridia, but positive in those from the normal limbal epithelium; whereas western blots showed that some epithelial clones expanded from pannus retained Pax6 expression. Transient transfection of an adenoviral vector carrying EGFP–Pax6 transgenes into these Pax6− clones increased both Pax6 and K12 keratin expression. These results indicate that Pax6 helps to maintain the normal corneal epithelial phenotype postnatally, and that down-regulation of Pax6 is associated with abnormal epidermal differentiation in severe ocular surface diseases. Reintroduction of activation of the Pax6 gene might be useful in treating squamous metaplasia of the ocular surface epithelium. PMID:18027901

  7. Expression of Tlx in both stem cells and transit amplifying progenitors regulates stem cell activation and differentiation in the neonatal lateral subependymal zone.

    Science.gov (United States)

    Obernier, Kirsten; Simeonova, Ina; Fila, Tatiana; Mandl, Claudia; Hölzl-Wenig, Gabriele; Monaghan-Nichols, Paula; Ciccolini, Francesca

    2011-09-01

    Niche homeostasis in the postnatal subependymal zone of the lateral ventricle (lSEZ) requires coordinated proliferation and differentiation of neural progenitor cells. The mechanisms regulating this balance are scarcely known. Recent observations indicate that the orphan nuclear receptor Tlx is an intrinsic factor essential in maintaining this balance. However, the effect of Tlx on gene expression depends on age and cell-type cues. Therefore, it is essential to establish its expression pattern at different developmental ages. Here, we show for the first time that in the neonatal lSEZ activated neural stem cells (NSCs) and especially transit-amplifying progenitors (TAPs) express Tlx and that its expression may be regulated at the posttranscriptional level. We also provide evidence that in both cell types Tlx affects gene expression in a positive and negative manner. In activated NSCs, but not in TAPs, absence of Tlx leads to overexpression of negative cell cycle regulators and impairment of proliferation. Moreover, in both cell types, the homeobox transcription factor Dlx2 is downregulated in the absence of Tlx. This is paralleled by increased expression of Olig2 in activated NSCs and glial fibrillary acidic protein in TAPs, indicating that in both populations Tlx decreases gliogenesis. Consistent with this, we found a higher proportion of cells expressing glial makers in the neonatal lSEZ of mutant mice than in the wild type counterpart. Thus, Tlx playing a dual role affects the expression of distinct genes in these two lSEZ cell types. Copyright © 2011 AlphaMed Press.

  8. The excretory-secretory products of Echinococcus granulosus protoscoleces directly regulate the differentiation of B10, B17 and Th17 cells.

    Science.gov (United States)

    Pan, Wei; Hao, Wen-Ting; Shen, Yu-Juan; Li, Xiang-Yang; Wang, Yan-Juan; Sun, Fen-Fen; Yin, Jian-Hai; Zhang, Jing; Tang, Ren-Xian; Cao, Jian-Ping; Zheng, Kui-Yang

    2017-07-21

    Excretory-secretory products (ESPs) released by helminths are well-known to regulate T cell responses in the host. However, their direct influence in the differentiation of naïve T cells, and especially B cells, remains largely unknown. This study investigated the effects of Echinococcus granulosus protoscoleces ESPs (EgPSC-ESPs) on the differentiation of IL-10-producing B cells (B10), IL-17A-producing B cells (B17) and Th17 cells. BALB/c mice injected with EgPSC were used to evaluate the in vivo profiles of B10, B17 and Th17 cells. In vitro purified CD19 + B and naïve CD4 + T cells were cultured in the presence of native, heat-inactivated or periodate-treated EgPSC-ESPs, and the differentiation of these cell subsets were compared. In contrast to the control group, infected mice showed higher frequencies of B10, B17 and Th17 cells, and higher levels of IL-10 and IL-17A in the sera. Interestingly, B17 cells were first identified to express CD19 + CD1d high . In vitro, B cells cultured with native ESPs exhibited a higher percentage of B10 cells but lower percentage of B17 and Th17 cells compared to the PBS group. Moreover, the relative expression of IL-10 and IL-17A mRNA were consistent with the altered frequencies. However, ESPs subjected to heat-inactivation or periodate treatment exhibited an inverse effect on the induction of these cell subsets. Our findings indicate that ESPs released by EgPSC can directly regulate the differentiation of B10, B17 and Th17 cells, which appear to be heat-labile and carbohydrate-dependent.

  9. Hyperglycemia Promotes Schwann Cell De-differentiation and De-myelination via Sorbitol Accumulation and Igf1 Protein Down-regulation.

    Science.gov (United States)

    Hao, Wu; Tashiro, Syoichi; Hasegawa, Tomoka; Sato, Yuiko; Kobayashi, Tami; Tando, Toshimi; Katsuyama, Eri; Fujie, Atsuhiro; Watanabe, Ryuichi; Morita, Mayu; Miyamoto, Kana; Morioka, Hideo; Nakamura, Masaya; Matsumoto, Morio; Amizuka, Norio; Toyama, Yoshiaki; Miyamoto, Takeshi

    2015-07-10

    Diabetes mellitus (DM) is frequently accompanied by complications, such as peripheral nerve neuropathy. Schwann cells play a pivotal role in regulating peripheral nerve function and conduction velocity; however, changes in Schwann cell differentiation status in DM are not fully understood. Here, we report that Schwann cells de-differentiate into immature cells under hyperglycemic conditions as a result of sorbitol accumulation and decreased Igf1 expression in those cells. We found that de-differentiated Schwann cells could be re-differentiated in vitro into mature cells by treatment with an aldose reductase inhibitor, to reduce sorbitol levels, or with vitamin D3, to elevate Igf1 expression. In vivo DM models exhibited significantly reduced nerve function and conduction, Schwann cell de-differentiation, peripheral nerve de-myelination, and all conditions were significantly rescued by aldose reductase inhibitor or vitamin D3 administration. These findings reveal mechanisms underlying pathological changes in Schwann cells seen in DM and suggest ways to treat neurological conditions associated with this condition. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  10. Hyperglycemia Promotes Schwann Cell De-differentiation and De-myelination via Sorbitol Accumulation and Igf1 Protein Down-regulation*

    Science.gov (United States)

    Hao, Wu; Tashiro, Syoichi; Hasegawa, Tomoka; Sato, Yuiko; Kobayashi, Tami; Tando, Toshimi; Katsuyama, Eri; Fujie, Atsuhiro; Watanabe, Ryuichi; Morita, Mayu; Miyamoto, Kana; Morioka, Hideo; Nakamura, Masaya; Matsumoto, Morio; Amizuka, Norio; Toyama, Yoshiaki; Miyamoto, Takeshi

    2015-01-01

    Diabetes mellitus (DM) is frequently accompanied by complications, such as peripheral nerve neuropathy. Schwann cells play a pivotal role in regulating peripheral nerve function and conduction velocity; however, changes in Schwann cell differentiation status in DM are not fully understood. Here, we report that Schwann cells de-differentiate into immature cells under hyperglycemic conditions as a result of sorbitol accumulation and decreased Igf1 expression in those cells. We found that de-differentiated Schwann cells could be re-differentiated in vitro into mature cells by treatment with an aldose reductase inhibitor, to reduce sorbitol levels, or with vitamin D3, to elevate Igf1 expression. In vivo DM models exhibited significantly reduced nerve function and conduction, Schwann cell de-differentiation, peripheral nerve de-myelination, and all conditions were significantly rescued by aldose reductase inhibitor or vitamin D3 administration. These findings reveal mechanisms underlying pathological changes in Schwann cells seen in DM and suggest ways to treat neurological conditions associated with this condition. PMID:25998127

  11. VEGF-C and TGF-β reciprocally regulate mesenchymal stem cell commitment to differentiation into lymphatic endothelial or osteoblastic phenotypes.

    Science.gov (United States)

    Igarashi, Yasuyuki; Chosa, Naoyuki; Sawada, Shunsuke; Kondo, Hisatomo; Yaegashi, Takashi; Ishisaki, Akira

    2016-04-01

    The direction of mesenchymal stem cell (MSC) differentiation is regulated by stimulation with various growth factors and cytokines. We recently established MSC lines, [transforming growth factor-β (TGF-β)-responsive SG‑2 cells, bone morphogenetic protein (BMP)-responsive SG‑3 cells, and TGF-β/BMP-non-responsive SG‑5 cells], derived from the bone marrow of green fluorescent protein-transgenic mice. In this study, to compare gene expression profiles in these MSC lines, we used DNA microarray analysis to characterize the specific gene expression profiles observed in the TGF-β-responsive SG‑2 cells. Among the genes that were highly expressed in the SG‑2 cells, we focused on vascular endothelial growth factor (VEGF) receptor 3 (VEGFR3), the gene product of FMS-like tyrosine kinase 4 (Flt4). We found that VEGF-C, a specific ligand of VEGFR3, significantly induced the cell proliferative activity, migratory ability (as shown by Transwell migration assay), as well as the phosphorylation of extracellular signal-regulated kinase (ERK)1/2 in the SG‑2 cells. Additionally, VEGF-C significantly increased the expression of prospero homeobox 1 (Prox1) and lymphatic vessel endothelial hyaluronan receptor 1 (Lyve1), which are lymphatic endothelial cell markers, and decreased the expression of osteogenic differentiation marker genes in these cells. By contrast, TGF-β significantly increased the expression of early-phase osteogenic differentiation marker genes in the SG‑2 cells and markedly decreased the expression of lymphatic endothelial cell markers. The findings of our study strongly suggest the following: i) that VEGF-C promotes the proliferative activity and migratory ability of MSCs; and ii) VEGF-C and TGF-β reciprocally regulate MSC commitment to differentiation into lymphatic endothelial or osteoblastic phenotypes, respectively. Our findings provide new insight into the molecular mechanisms underlying the regenerative ability of MSCs.

  12. Criticality in cell differentiation

    Indian Academy of Sciences (India)

    Indrani Bose

    2017-11-09

    Nov 9, 2017 ... Differentiation is mostly based on binary decisions with the progenitor cells ..... accounts for the dominant part of the remaining variation ... significant loss in information. ..... making in vitro: emerging concepts and novel tools.

  13. miR-200c and GATA binding protein 4 regulate human embryonic stem cell renewal and differentiation

    Directory of Open Access Journals (Sweden)

    Hsiao-Ning Huang

    2014-03-01

    Full Text Available Human embryonic stem cells (hESCs are functionally unique for their self-renewal ability and pluripotency, but the molecular mechanisms giving rise to these properties are not fully understood. hESCs can differentiate into embryoid bodies (EBs containing ectoderm, mesoderm, and endoderm. In the miR-200 family, miR-200c was especially enriched in undifferentiated hESCs and significantly downregulated in EBs. The knockdown of the miR-200c in hESCs downregulated Nanog expression, upregulated GATA binding protein 4 (GATA4 expression, and induced hESC apoptosis. The knockdown of GATA4 rescued hESC apoptosis induced by downregulation of miR-200c. miR-200c directly targeted the 3′-untranslated region of GATA4. Interestingly, the downregulation of GATA4 significantly inhibited EB formation in hESCs. Overexpression of miR-200c inhibited EB formation and repressed the expression of ectoderm, endoderm, and mesoderm markers, which could partially be rescued by ectopic expression of GATA4. Fibroblast growth factor (FGF and activin A/nodal can sustain hESC renewal in the absence of feeder layer. Inhibition of transforming growth factor-β (TGF-β/activin A/nodal signaling by SB431542 treatment downregulated the expression of miR-200c. Overexpression of miR-200c partially rescued the expression of Nanog/phospho-Smad2 that was downregulated by SB431542 treatment. Our observations have uncovered novel functions of miR-200c and GATA4 in regulating hESC renewal and differentiation.

  14. miR-373 is regulated by TGFβ signaling and promotes mesendoderm differentiation in human Embryonic Stem Cells

    Science.gov (United States)

    Rosa, Alessandro; Papaioannou, Marilena D.; Krzyspiak, Joanna E.; Brivanlou, Ali H.

    2014-01-01

    MicroRNAs (miRNAs) belonging to the evolutionary conserved miR-302 family play important functions in Embryonic Stem Cells (ESCs). The expression of some members, such as the human miR-302 and mouse miR-290 clusters, is regulated by ESC core transcription factors. However, whether miRNAs act downstream of signaling pathways involved in human ESC pluripotency remains unknown. The maintenance of pluripotency in hESCs is under the control of the TGFβ pathway. Here, we show that inhibition of the Activin/Nodal branch of this pathway affects the expression of a subset of miRNAs in hESCs. Among them, we found miR-373, a member of the miR-302 family. Proper levels of miR-373 are crucial for the maintenance of hESC pluripotency, since its overexpression leads to differentiation towards the mesendodermal lineage. Among miR-373 predicted targets, involved in TGFβ signaling, we validated the Nodal inhibitor Lefty. Our work suggests a crucial role for the interplay between miRNAs and signaling pathways in ESCs. PMID:24709321

  15. Isolation and characterization of beta-glucan synthase: A potential biochemical regulator of gravistimulated differential cell wall loosening

    Science.gov (United States)

    Kuzmanoff, K. M.

    1984-01-01

    In plants, gravity stimulates differential growth in the upper and lower halves of horizontally oriented organs. Auxin regulation of cell wall loosening and elongation is the basis for most models of this phenomenon. Auxin treatment of pea stem tissue rapidly increases the activity of Golgi-localized Beta-1,4-glucan synthase, an enzyme involved in biosynthesis of wall xyloglucan which apparently constitutes the substrate for the wall loosening process. The primary objective is to determine if auxin induces de novo formation of Golgi glucan synthase and increases the level of this glucan synthase mRNA. This shall be accomplished by (a) preparation of a monoclonal antibody to the synthase, (b) isolation, and characterization of the glucan synthase, and (c) examination for cross reactivity between the antibody and translation products of auxin induced mRNAs in pea tissue. The antibody will also be used to localize the glucan synthase in upper and lower halves of pea stem tissue before, during and after the response to gravity.

  16. Hematopoietic stem/progenitor cell proliferation and differentiation is differentially regulated by high-density and low-density lipoproteins in mice.

    Directory of Open Access Journals (Sweden)

    Yingmei Feng

    Full Text Available RATIONALE: Hematopoietic stem/progenitor cells (HSPC are responsible for maintaining the blood system as a result of their self-renewal and multilineage differentiation capacity. Recently, studies have suggested that HDL cholesterol may inhibit and impaired cholesterol efflux may increase HSPC proliferation and differentiation. OBJECTIVES: We hypothesized that LDL may enhance HSPC proliferation and differentiation while HDL might have the opposing effect which might influence the size of the pool of inflammatory cells. METHODS AND RESULTS: HSPC number and function were studied in hypercholesterolemic LDL receptor knockout (LDLr(-/- mice on high fat diet. Hypercholesterolemia was associated with increased frequency of HSPC, monocytes and granulocytes in the peripheral blood (PB. In addition, an increased proportion of BM HSPC was in G(2M of the cell cycle, and the percentage of HSPC and granulocyte-macrophage progenitors (GMP increased in BM of LDLr(-/- mice. When BM Lin-Sca-1+cKit+ (i.e. "LSK" cells were cultured in the presence of LDL in vitro we also found enhanced differentiation towards monocytes and granulocytes. Furthermore, LDL promoted lineage negative (Lin- cells motility. The modulation by LDL on HSPC differentiation into granulocytes and motility was inhibited by inhibiting ERK phosphorylation. By contrast, when mice were infused with human apoA-I (the major apolipoprotein of HDL or reconstituted HDL (rHDL, the frequency and proliferation of HSPC was reduced in BM in vivo. HDL also reversed the LDL-induced monocyte and granulocyte differentiation in vitro. CONCLUSION: Our data suggest that LDL and HDL have opposing effects on HSPC proliferation and differentiation. It will be of interest to determine if breakdown of HSPC homeostasis by hypercholesterolemia contributes to inflammation and atherosclerosis progression.

  17. MicroRNA-4739 regulates osteogenic and adipocytic differentiation of immortalized human bone marrow stromal cells via targeting LRP3

    DEFF Research Database (Denmark)

    Elsafadi, Mona; Manikandan, Muthurangan; Alajez, Nehad M

    2017-01-01

    3 (LRP3) in regulating the osteogenic and adipogenic differentiation of immortalized hBMSCs. Gene expression profiling revealed significantly higher LRP3 levels in the highly osteogenic hBMSC clone imCL1 than in the less osteogenic clone imCL2, as well as a significant upregulation of LRP3 during...

  18. Amyloid protein-mediated differential DNA methylation status regulates gene expression in Alzheimer’s disease model cell line

    International Nuclear Information System (INIS)

    Sung, Hye Youn; Choi, Eun Nam; Ahn Jo, Sangmee; Oh, Seikwan; Ahn, Jung-Hyuck

    2011-01-01

    Highlights: ► Genome-wide DNA methylation pattern in Alzheimer’s disease model cell line. ► Integrated analysis of CpG methylation and mRNA expression profiles. ► Identify three Swedish mutant target genes; CTIF, NXT2 and DDR2 gene. ► The effect of Swedish mutation on alteration of DNA methylation and gene expression. -- Abstract: The Swedish mutation of amyloid precursor protein (APP-sw) has been reported to dramatically increase beta amyloid production through aberrant cleavage at the beta secretase site, causing early-onset Alzheimer’s disease (AD). DNA methylation has been reported to be associated with AD pathogenesis, but the underlying molecular mechanism of APP-sw-mediated epigenetic alterations in AD pathogenesis remains largely unknown. We analyzed genome-wide interplay between promoter CpG DNA methylation and gene expression in an APP-sw-expressing AD model cell line. To identify genes whose expression was regulated by DNA methylation status, we performed integrated analysis of CpG methylation and mRNA expression profiles, and identified three target genes of the APP-sw mutant; hypomethylated CTIF (CBP80/CBP20-dependent translation initiation factor) and NXT2 (nuclear exporting factor 2), and hypermethylated DDR2 (discoidin domain receptor 2). Treatment with the demethylating agent 5-aza-2′-deoxycytidine restored mRNA expression of these three genes, implying methylation-dependent transcriptional regulation. The profound alteration in the methylation status was detected at the −435, −295, and −271 CpG sites of CTIF, and at the −505 to −341 region in the promoter of DDR2. In the promoter region of NXT2, only one CpG site located at −432 was differentially unmethylated in APP-sw cells. Thus, we demonstrated the effect of the APP-sw mutation on alteration of DNA methylation and subsequent gene expression. This epigenetic regulatory mechanism may contribute to the pathogenesis of AD.

  19. Differential requirement for the CD45 splicing regulator hnRNPLL for accumulation of NKT and conventional T cells.

    Directory of Open Access Journals (Sweden)

    Mehmet Yabas

    Full Text Available Natural killer T (NKT cells represent an important regulatory T cell subset that develops in the thymus and contains immature (NK1.1(lo and mature (NK1.1(hi cell subsets. Here we show in mice that an inherited mutation in heterogeneous ribonucleoprotein L-like protein (hnRNPLL(thunder, that shortens the survival of conventional T cells, has no discernible effect on NKT cell development, homeostasis or effector function. Thus, Hnrpll deficiency effectively increases the NKT∶T cell ratio in the periphery. However, Hnrpll mutation disrupts CD45RA, RB and RC exon silencing of the Ptprc mRNA in both NKT and conventional T cells, and leads to a comparably dramatic shift to high molecular weight CD45 isoforms. In addition, Hnrpll mutation has a cell intrinsic effect on the expression of the developmentally regulated cell surface marker NK1.1 on NKT cells in the thymus and periphery but does not affect cell numbers. Therefore our results highlight both overlapping and divergent roles for hnRNPLL between conventional T cells and NKT cells. In both cell subsets it is required as a trans-acting factor to regulate alternative splicing of the Ptprc mRNA, but it is only required for survival of conventional T cells.

  20. Regulation of beta cell replication

    DEFF Research Database (Denmark)

    Lee, Ying C; Nielsen, Jens Høiriis

    2008-01-01

    Beta cell mass, at any given time, is governed by cell differentiation, neogenesis, increased or decreased cell size (cell hypertrophy or atrophy), cell death (apoptosis), and beta cell proliferation. Nutrients, hormones and growth factors coupled with their signalling intermediates have been...... suggested to play a role in beta cell mass regulation. In addition, genetic mouse model studies have indicated that cyclins and cyclin-dependent kinases that determine cell cycle progression are involved in beta cell replication, and more recently, menin in association with cyclin-dependent kinase...... inhibitors has been demonstrated to be important in beta cell growth. In this review, we consider and highlight some aspects of cell cycle regulation in relation to beta cell replication. The role of cell cycle regulation in beta cell replication is mostly from studies in rodent models, but whether...

  1. Membrane-Type 1 Matrix Metal loproteinase Is Regulated by Sp1 through the Differential Activation of AKT, JNK, and ERK Pathways in Human Prostate Tumor Cells

    Directory of Open Access Journals (Sweden)

    Isis C. Sroka

    2007-05-01

    Full Text Available We and other investigators have previously shown that membrane-type 1 matrix metalloproteinase (MT1-MMP is overexpressed in invasive prostate cancer cells. However, the mechanism for this expression is not known. Here, we show that MT1-MMP is minimally expressed in nonmalignant primary prostate cells, moderately expressed in DU-145 cells, and highly expressed in invasive PC-3 and PC-3N cells. Using human MT1-MMP promoter reporter plasmids and mobility shift assays, we show that Spi regulates MT1-MMP expression in DU-145, PC-3, and PC-3N cells and in PC3-N cells using chromatin immunoprecipitation analysis and silencing RNA. Investigation of signaling pathway showed that DU-145 cells express constitutively phosphorylated extracellular stress-regulated kinase (ERK, whereas PC-3 and PC-3N cells express constitutively phosphorylated AKT/PKB and c-Jun NH2 terminal kinase (JNK. We show that MT1-MMP and Spi levels are decreased in PC-3 and PC-3N cells when phosphatidylinositol-3 kinase and JNK are inhibited, and that MT1-MMP levels are decreased in DU-145 cells when MEK is inhibited. Transient transfection of PC-3 and PC-3N cells with a dominant-negative JNK or p85, and of DU-145 cells with a dominant negative ERK, reduces MT1-MMP promoter activity. These results indicate differential signaling control of Spi-mediated transcriptional regulation of MT1-MMP in prostate cancer cell lines.

  2. Dual Functions of Natural Killer Cells in Selection and Differentiation of Stem Cells; Role in Regulation of Inflammation and Regeneration of Tissues

    Directory of Open Access Journals (Sweden)

    Anahid Jewett, Yan-Gao Man, Han-Ching Tseng

    2013-01-01

    Full Text Available Accumulated evidence from our laboratory indicates that conditioned or anergized NK cells have the ability to induce resistance of healthy stem cells and transformed cancer stem cells through both secreted factors and direct cell-cell contact by inducing differentiation. Cytotoxic function of NK cells is suppressed in the tumor microenvironment by a number of distinct effectors and their secreted factors. Furthermore, decreased peripheral blood NK cell function has been documented in many cancer patients. We have previously shown that NK cells mediate significant cytotoxicity against primary oral squamous carcinoma stem cells (OSCSCs as compared to their more differentiated oral squamous carcinoma cells (OSCCs. In addition, human embryonic stem cells (hESCs, human mesenchymal stem cells (hMSCs, human dental pulp stem cells (hDPSCs and induced human pluripotent stem cells (hiPSCs were all significantly more susceptible to NK cell mediated cytotoxicity than their differentiated counterparts or parental cells from which they were derived. We have also reported that inhibition of differentiation or reversion of cells to a less-differentiated phenotype by blocking NFκB or gene deletion of COX2 significantly augmented NK cell function. Furthermore, the induction of resistance of the stem cells to NK cell mediated cytotoxicity and their subsequent differentiation is amplified when either the stem cells or the NK cells were cultured in the presence of monocytes. Therefore, we propose that the two stages of NK cell maturation namely CD16+CD56dimCD69- NK cells are important for the lysis of stem cells or poorly differentiated cells whereas the CD16dim/-CD56dim/+CD69+NK cells are important for differentiation and eventual regeneration of the tissues and the resolution of inflammation, thus functionally serving as regulatory NK cells (NKreg. CD16 receptor on the NK cells were found to be the receptor with significant potential to induce NK cell anergy

  3. Opposing regulation of PROX1 by interleukin-3 receptor and NOTCH directs differential host cell fate reprogramming by Kaposi sarcoma herpes virus.

    Directory of Open Access Journals (Sweden)

    Jaehyuk Yoo

    Full Text Available Lymphatic endothelial cells (LECs are differentiated from blood vascular endothelial cells (BECs during embryogenesis and this physiological cell fate specification is controlled by PROX1, the master regulator for lymphatic development. When Kaposi sarcoma herpes virus (KSHV infects host cells, it activates the otherwise silenced embryonic endothelial differentiation program and reprograms their cell fates. Interestingly, previous studies demonstrated that KSHV drives BECs to acquire a partial lymphatic phenotype by upregulating PROX1 (forward reprogramming, but stimulates LECs to regain some BEC-signature genes by downregulating PROX1 (reverse reprogramming. Despite the significance of this KSHV-induced bidirectional cell fate reprogramming in KS pathogenesis, its underlying molecular mechanism remains undefined. Here, we report that IL3 receptor alpha (IL3Rα and NOTCH play integral roles in the host cell type-specific regulation of PROX1 by KSHV. In BECs, KSHV upregulates IL3Rα and phosphorylates STAT5, which binds and activates the PROX1 promoter. In LECs, however, PROX1 was rather downregulated by KSHV-induced NOTCH signal via HEY1, which binds and represses the PROX1 promoter. Moreover, PROX1 was found to be required to maintain HEY1 expression in LECs, establishing a reciprocal regulation between PROX1 and HEY1. Upon co-activation of IL3Rα and NOTCH, PROX1 was upregulated in BECs, but downregulated in LECs. Together, our study provides the molecular mechanism underlying the cell type-specific endothelial fate reprogramming by KSHV.

  4. Interferon-γ regulates the proliferation and differentiation of mesenchymal stem cells via activation of indoleamine 2,3 dioxygenase (IDO.

    Directory of Open Access Journals (Sweden)

    Juliana Croitoru-Lamoury

    Full Text Available The kynurenine pathway (KP of tryptophan metabolism is linked to antimicrobial activity and modulation of immune responses but its role in stem cell biology is unknown. We show that human and mouse mesenchymal and neural stem cells (MSCs and NSCs express the complete KP, including indoleamine 2,3 dioxygenase 1 (IDO and IDO2, that it is highly regulated by type I (IFN-β and II interferons (IFN-γ, and that its transcriptional modulation depends on the type of interferon, cell type and species. IFN-γ inhibited proliferation and altered human and mouse MSC neural, adipocytic and osteocytic differentiation via the activation of IDO. A functional KP present in MSCs, NSCs and perhaps other stem cell types offers novel therapeutic opportunities for optimisation of stem cell proliferation and differentiation.

  5. YAP regulates neuronal differentiation through Sonic hedgehog signaling pathway

    International Nuclear Information System (INIS)

    Lin, Yi-Ting; Ding, Jing-Ya; Li, Ming-Yang; Yeh, Tien-Shun; Wang, Tsu-Wei; Yu, Jenn-Yah

    2012-01-01

    Tight regulation of cell numbers by controlling cell proliferation and apoptosis is important during development. Recently, the Hippo pathway has been shown to regulate tissue growth and organ size in Drosophila. In mammalian cells, it also affects cell proliferation and differentiation in various tissues, including the nervous system. Interplay of several signaling cascades, such as Notch, Wnt, and Sonic Hedgehog (Shh) pathways, control cell proliferation during neuronal differentiation. However, it remains unclear whether the Hippo pathway coordinates with other signaling cascades in regulating neuronal differentiation. Here, we used P19 cells, a mouse embryonic carcinoma cell line, as a model to study roles of YAP, a core component of the Hippo pathway, in neuronal differentiation. P19 cells can be induced to differentiate into neurons by expressing a neural bHLH transcription factor gene Ascl1. Our results showed that YAP promoted cell proliferation and inhibited neuronal differentiation. Expression of Yap activated Shh but not Wnt or Notch signaling activity during neuronal differentiation. Furthermore, expression of Yap increased the expression of Patched homolog 1 (Ptch1), a downstream target of the Shh signaling. Knockdown of Gli2, a transcription factor of the Shh pathway, promoted neuronal differentiation even when Yap was over-expressed. We further demonstrated that over-expression of Yap inhibited neuronal differentiation in primary mouse cortical progenitors and Gli2 knockdown rescued the differentiation defect in Yap over-expressing cells. In conclusion, our study reveals that Shh signaling acts downstream of YAP in regulating neuronal differentiation. -- Highlights: ► YAP promotes cell proliferation and inhibits neuronal differentiation in P19 cells. ► YAP promotes Sonic hedgehog signaling activity during neuronal differentiation. ► Knockdown of Gli2 rescues the Yap-overexpression phenotype in P19 cells. ► Knockdown of Gli2 rescues the Yap

  6. YAP regulates neuronal differentiation through Sonic hedgehog signaling pathway

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Yi-Ting; Ding, Jing-Ya [Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taipei 112, Taiwan (China); Li, Ming-Yang [Department of Life Science, National Taiwan Normal University, Taipei 116, Taiwan (China); Yeh, Tien-Shun [Department of Anatomy and Cell Biology, National Yang-Ming University, Taipei 112, Taiwan (China); Wang, Tsu-Wei [Department of Life Science, National Taiwan Normal University, Taipei 116, Taiwan (China); Yu, Jenn-Yah [Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taipei 112, Taiwan (China); Brain Research Center, National Yang-Ming University, Taipei 112, Taiwan (China)

    2012-09-10

    Tight regulation of cell numbers by controlling cell proliferation and apoptosis is important during development. Recently, the Hippo pathway has been shown to regulate tissue growth and organ size in Drosophila. In mammalian cells, it also affects cell proliferation and differentiation in various tissues, including the nervous system. Interplay of several signaling cascades, such as Notch, Wnt, and Sonic Hedgehog (Shh) pathways, control cell proliferation during neuronal differentiation. However, it remains unclear whether the Hippo pathway coordinates with other signaling cascades in regulating neuronal differentiation. Here, we used P19 cells, a mouse embryonic carcinoma cell line, as a model to study roles of YAP, a core component of the Hippo pathway, in neuronal differentiation. P19 cells can be induced to differentiate into neurons by expressing a neural bHLH transcription factor gene Ascl1. Our results showed that YAP promoted cell proliferation and inhibited neuronal differentiation. Expression of Yap activated Shh but not Wnt or Notch signaling activity during neuronal differentiation. Furthermore, expression of Yap increased the expression of Patched homolog 1 (Ptch1), a downstream target of the Shh signaling. Knockdown of Gli2, a transcription factor of the Shh pathway, promoted neuronal differentiation even when Yap was over-expressed. We further demonstrated that over-expression of Yap inhibited neuronal differentiation in primary mouse cortical progenitors and Gli2 knockdown rescued the differentiation defect in Yap over-expressing cells. In conclusion, our study reveals that Shh signaling acts downstream of YAP in regulating neuronal differentiation. -- Highlights: Black-Right-Pointing-Pointer YAP promotes cell proliferation and inhibits neuronal differentiation in P19 cells. Black-Right-Pointing-Pointer YAP promotes Sonic hedgehog signaling activity during neuronal differentiation. Black-Right-Pointing-Pointer Knockdown of Gli2 rescues the Yap

  7. Nuclear Factor Erythroid 2 Regulates Human HSC Self-Renewal and T Cell Differentiation by Preventing NOTCH1 Activation.

    Science.gov (United States)

    Di Tullio, Alessandro; Passaro, Diana; Rouault-Pierre, Kevin; Purewal, Sukhveer; Bonnet, Dominique

    2017-07-11

    Nuclear factor erythroid-derived 2 (NF-E2) has been associated with megakaryocyte maturation and platelet production. Recently, an increased in NF-E2 activity has been implicated in myeloproliferative neoplasms. Here, we investigate the role of NF-E2 in normal human hematopoiesis. Knockdown of NF-E2 in the hematopoietic stem and progenitor cells (HSPCs) not only reduced the formation of megakaryocytes but also drastically impaired hematopoietic stem cell activity, decreasing human engraftment in immunodeficient (NSG) mice. This phenotype is likely to be related to both increased cell proliferation (p21-mediated) and reduced Notch1 protein expression, which favors HSPC differentiation over self-renewal. Strikingly, although NF-E2 silencing in HSPCs did not affect their myeloid and B cell differentiation in vivo, it almost abrogated T cell production in primary hosts, as confirmed by in vitro studies. This effect is at least partly due to Notch1 downregulation in NF-E2-silenced HSPCs. Together these data reveal that NF-E2 is an important driver of human hematopoietic stem cell maintenance and T lineage differentiation. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

  8. Nuclear Factor Erythroid 2 Regulates Human HSC Self-Renewal and T Cell Differentiation by Preventing NOTCH1 Activation

    Directory of Open Access Journals (Sweden)

    Alessandro Di Tullio

    2017-07-01

    Full Text Available Nuclear factor erythroid-derived 2 (NF-E2 has been associated with megakaryocyte maturation and platelet production. Recently, an increased in NF-E2 activity has been implicated in myeloproliferative neoplasms. Here, we investigate the role of NF-E2 in normal human hematopoiesis. Knockdown of NF-E2 in the hematopoietic stem and progenitor cells (HSPCs not only reduced the formation of megakaryocytes but also drastically impaired hematopoietic stem cell activity, decreasing human engraftment in immunodeficient (NSG mice. This phenotype is likely to be related to both increased cell proliferation (p21-mediated and reduced Notch1 protein expression, which favors HSPC differentiation over self-renewal. Strikingly, although NF-E2 silencing in HSPCs did not affect their myeloid and B cell differentiation in vivo, it almost abrogated T cell production in primary hosts, as confirmed by in vitro studies. This effect is at least partly due to Notch1 downregulation in NF-E2-silenced HSPCs. Together these data reveal that NF-E2 is an important driver of human hematopoietic stem cell maintenance and T lineage differentiation.

  9. Proliferation and osteo/odontogenic differentiation of stem cells from apical papilla regulated by Zinc fingers and homeoboxes 2: An in vitro study

    International Nuclear Information System (INIS)

    Wan, Fang; Gao, Lifen; Lu, Yating; Ma, Hongxin; Wang, Hongxing; Liang, Xiaohong; Wang, Yan; Ma, Chunhong

    2016-01-01

    In the process of tooth root development, stem cells from the apical papilla (SCAPs) can differentiate into odontoblasts and form root dentin, however, molecules regulating SCAPs differentiation have not been elucidated. Zinc fingers and homeoboxes 2 (ZHX2) is a novel transcriptional inhibitor. It is reported to modulate the development of nerve cells, liver cells, B cells, red blood cells, and so on. However, the role of ZHX2 in tooth root development remains unclear. In this study, we explored the potential role of ZHX2 in the process of SCAPs differentiation. The results showed that overexpression of ZHX2 upregulated the expression of osteo/odontogenic related genes and ALP activity, inhibited the proliferation of SCAPs. Consistently, ZHX2 knockdown reduced SCAPs mineralization and promoted SCAPs proliferation. These results indicated that ZHX2 plays a critical role in the proliferation and osteo/odontogenic differentiation of SCAPs. - Highlights: • Zinc fingers and homeoboxes 2 (ZHX2) is a novel transcriptional inhibitor. • we found another new biological function of ZHX2 for the first time. • ZHX2 inhibit SCAPs proliferation. • ZHX2 promote the osteo/odontogenic differentiation of SCAPs.

  10. Proliferation and osteo/odontogenic differentiation of stem cells from apical papilla regulated by Zinc fingers and homeoboxes 2: An in vitro study

    Energy Technology Data Exchange (ETDEWEB)

    Wan, Fang [Department of Immunology, Key Laboratory for Experimental Teratology of Ministry of Education, Shandong Provincial Key Laboratory of Infection & Immunology, Shandong University School of Medicine, 44 Wenhua Xi Road, Jinan, Shandong 250012 (China); VIP Center, Shandong Provincial Key Laboratory of Oral Biomedicine, School and Hospital of Stomatology, Shandong University, 44 Wenhua Xi Road, Jinan, Shandong 250012 (China); Gao, Lifen [Department of Immunology, Key Laboratory for Experimental Teratology of Ministry of Education, Shandong Provincial Key Laboratory of Infection & Immunology, Shandong University School of Medicine, 44 Wenhua Xi Road, Jinan, Shandong 250012 (China); Lu, Yating [VIP Center, Shandong Provincial Key Laboratory of Oral Biomedicine, School and Hospital of Stomatology, Shandong University, 44 Wenhua Xi Road, Jinan, Shandong 250012 (China); Ma, Hongxin; Wang, Hongxing; Liang, Xiaohong [Department of Immunology, Key Laboratory for Experimental Teratology of Ministry of Education, Shandong Provincial Key Laboratory of Infection & Immunology, Shandong University School of Medicine, 44 Wenhua Xi Road, Jinan, Shandong 250012 (China); Wang, Yan, E-mail: wangyan1965@sdu.edu.cn [VIP Center, Shandong Provincial Key Laboratory of Oral Biomedicine, School and Hospital of Stomatology, Shandong University, 44 Wenhua Xi Road, Jinan, Shandong 250012 (China); Ma, Chunhong, E-mail: machunhong@sdu.edu.cn [Department of Immunology, Key Laboratory for Experimental Teratology of Ministry of Education, Shandong Provincial Key Laboratory of Infection & Immunology, Shandong University School of Medicine, 44 Wenhua Xi Road, Jinan, Shandong 250012 (China)

    2016-01-15

    In the process of tooth root development, stem cells from the apical papilla (SCAPs) can differentiate into odontoblasts and form root dentin, however, molecules regulating SCAPs differentiation have not been elucidated. Zinc fingers and homeoboxes 2 (ZHX2) is a novel transcriptional inhibitor. It is reported to modulate the development of nerve cells, liver cells, B cells, red blood cells, and so on. However, the role of ZHX2 in tooth root development remains unclear. In this study, we explored the potential role of ZHX2 in the process of SCAPs differentiation. The results showed that overexpression of ZHX2 upregulated the expression of osteo/odontogenic related genes and ALP activity, inhibited the proliferation of SCAPs. Consistently, ZHX2 knockdown reduced SCAPs mineralization and promoted SCAPs proliferation. These results indicated that ZHX2 plays a critical role in the proliferation and osteo/odontogenic differentiation of SCAPs. - Highlights: • Zinc fingers and homeoboxes 2 (ZHX2) is a novel transcriptional inhibitor. • we found another new biological function of ZHX2 for the first time. • ZHX2 inhibit SCAPs proliferation. • ZHX2 promote the osteo/odontogenic differentiation of SCAPs.

  11. Estrogen-Induced Maldevelopment of the Penis Involves Down-Regulation of Myosin Heavy Chain 11 (MYH11) Expression, a Biomarker for Smooth Muscle Cell Differentiation1

    Science.gov (United States)

    Okumu, L.A.; Bruinton, Sequoia; Braden, Tim D.; Simon, Liz; Goyal, Hari O.

    2012-01-01

    ABSTRACT Cavernous smooth muscle cells are essential components in penile erection. In this study, we investigated effects of estrogen exposure on biomarkers for smooth muscle cell differentiation in the penis. Neonatal rats received diethylstilbestrol (DES), with or without the estrogen receptor (ESR) antagonist ICI 182,780 (ICI) or the androgen receptor (AR) agonist dihydrotestosterone (DHT), from Postnatal Days 1 to 6. Tissues were collected at 7, 10, or 21 days of age. The smooth muscle cell biomarker MYH11 was studied in depth because microarray data showed it was significantly down-regulated, along with other biomarkers, in DES treatment. Quantitative real time-PCR and Western blot analyses showed 50%–80% reduction (P ≤ 0.05) in Myh11 expression in DES-treated rats compared to that in controls; and ICI and DHT coadministration mitigated the decrease. Temporally, from 7 to 21 days of age, Myh11 expression was onefold increased (P ≥ 0.05) in DES-treated rats versus threefold increased (P ≤ 0.001) in controls, implying the long-lasting inhibitory effect of DES on smooth muscle cell differentiation. Immunohistochemical localization of smooth muscle alpha actin, another biomarker for smooth muscle cell differentiation, showed fewer cavernous smooth muscle cells in DES-treated animals than in controls. Additionally, DES treatment significantly up-regulated Esr1 mRNA expression and suppressed the neonatal testosterone surge by 90%, which was mitigated by ICI coadministration but not by DHT coadministration. Collectively, results provided evidence that DES treatment in neonatal rats inhibited cavernous smooth muscle cell differentiation, as shown by down-regulation of MYH11 expression at the mRNA and protein levels and by reduced immunohistochemical staining of smooth muscle alpha actin. Both the ESR and the AR pathways probably mediate this effect. PMID:22976277

  12. miR-150 Regulates Memory CD8 T Cell Differentiation via c-Myb

    Directory of Open Access Journals (Sweden)

    Zeyu Chen

    2017-09-01

    Full Text Available MicroRNAs play an important role in T cell responses. However, how microRNAs regulate CD8 T cell memory remains poorly defined. Here, we found that miR-150 negatively regulates CD8 T cell memory in vivo. Genetic deletion of miR-150 disrupted the balance between memory precursor and terminal effector CD8 T cells following acute viral infection. Moreover, miR-150-deficient memory CD8 T cells were more protective upon rechallenge. A key circuit whereby miR-150 repressed memory CD8 T cell development through the transcription factor c-Myb was identified. Without miR-150, c-Myb was upregulated and anti-apoptotic targets of c-Myb, such as Bcl-2 and Bcl-xL, were also increased, suggesting a miR-150-c-Myb survival circuit during memory CD8 T cell development. Indeed, overexpression of non-repressible c-Myb rescued the memory CD8 T cell defects caused by overexpression of miR-150. Overall, these results identify a key role for miR-150 in memory CD8 T cells through a c-Myb-controlled enhanced survival circuit.

  13. Differential Regulation of Gene Expression of Alveolar Epithelial Cell Markers in Human Lung Adenocarcinoma-Derived A549 Clones

    Directory of Open Access Journals (Sweden)

    Hiroshi Kondo

    2015-01-01

    Full Text Available Stem cell therapy appears to be promising for restoring damaged or irreparable lung tissue. However, establishing a simple and reproducible protocol for preparing lung progenitor populations is difficult because the molecular basis for alveolar epithelial cell differentiation is not fully understood. We investigated an in vitro system to analyze the regulatory mechanisms of alveolus-specific gene expression using a human alveolar epithelial type II (ATII cell line, A549. After cloning A549 subpopulations, each clone was classified into five groups according to cell morphology and marker gene expression. Two clones (B7 and H12 were further analyzed. Under serum-free culture conditions, surfactant protein C (SPC, an ATII marker, was upregulated in both H12 and B7. Aquaporin 5 (AQP5, an ATI marker, was upregulated in H12 and significantly induced in B7. When the RAS/MAPK pathway was inhibited, SPC and thyroid transcription factor-1 (TTF-1 expression levels were enhanced. After treatment with dexamethasone (DEX, 8-bromoadenosine 3′5′-cyclic monophosphate (8-Br-cAMP, 3-isobutyl-1-methylxanthine (IBMX, and keratinocyte growth factor (KGF, surfactant protein B and TTF-1 expression levels were enhanced. We found that A549-derived clones have plasticity in gene expression of alveolar epithelial differentiation markers and could be useful in studying ATII maintenance and differentiation.

  14. Differential Rac1 signalling by guanine nucleotide exchange factors implicates FLII in regulating Rac1-driven cell migration

    Science.gov (United States)

    Marei, Hadir; Carpy, Alejandro; Woroniuk, Anna; Vennin, Claire; White, Gavin; Timpson, Paul; Macek, Boris; Malliri, Angeliki

    2016-01-01

    The small GTPase Rac1 has been implicated in the formation and dissemination of tumours. Upon activation by guanine nucleotide exchange factors (GEFs), Rac1 associates with a variety of proteins in the cell thereby regulating various functions, including cell migration. However, activation of Rac1 can lead to opposing migratory phenotypes raising the possibility of exacerbating tumour progression when targeting Rac1 in a clinical setting. This calls for the identification of factors that influence Rac1-driven cell motility. Here we show that Tiam1 and P-Rex1, two Rac GEFs, promote Rac1 anti- and pro-migratory signalling cascades, respectively, through regulating the Rac1 interactome. In particular, we demonstrate that P-Rex1 stimulates migration through enhancing the interaction between Rac1 and the actin-remodelling protein flightless-1 homologue, to modulate cell contraction in a RhoA-ROCK-independent manner. PMID:26887924

  15. bHLH-O proteins balance the self-renewal and differentiation of Drosophila neural stem cells by regulating Earmuff expression.

    Science.gov (United States)

    Li, Xiaosu; Chen, Rui; Zhu, Sijun

    2017-11-15

    Balancing self-renewal and differentiation of stem cells requires differential expression of self-renewing factors in two daughter cells generated from the asymmetric division of the stem cells. In Drosophila type II neural stem cell (or neuroblast, NB) lineages, the expression of the basic helix-loop-helix-Orange (bHLH-O) family proteins, including Deadpan (Dpn) and E(spl) proteins, is required for maintaining the self-renewal and identity of type II NBs, whereas the absence of these self-renewing factors is essential for the differentiation of intermediate neural progenitors (INPs) generated from type II NBs. Here, we demonstrate that Dpn maintains type II NBs by suppressing the expression of Earmuff (Erm). We provide evidence that Dpn and E(spl) proteins suppress Erm by directly binding to C-sites and N-boxes in the cis-regulatory region of erm. Conversely, the absence of bHLH-O proteins in INPs allows activation of erm and Erm-mediated maturation of INPs. Our results further suggest that Pointed P1 (PntP1) mediates the dedifferentiation of INPs resulting from the loss of Erm or overexpression of Dpn or E(spl) proteins. Taken together, these findings reveal mechanisms underlying the regulation of the maintenance of type II NBs and differentiation of INPs through the differential expression of bHLH-O family proteins. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Distinct roles of the receptor tyrosine kinases c-ErbB and c-Kit in regulating the balance between erythroid cell proliferation and differentiation

    NARCIS (Netherlands)

    Wessely, O.; Mellitzer, G.; von Lindern, M.; Levitzki, A.; Gazit, A.; Ischenko, I.; Hayman, M. J.; Beug, H.

    1997-01-01

    In the bone marrow, multipotent and committed hematopoietic progenitors have to closely regulate their balance between sustained proliferation without differentiation (self renewal) and entering a terminal differentiation pathway. A useful model to analyze this regulation at the molecular level is

  17. Foxo1 and Foxp1 play opposing roles in regulating the differentiation and antitumor activity of TH9 cells programmed by IL-7

    Science.gov (United States)

    Bi, Enguang; Ma, Xingzhe; Lu, Yong; Yang, Maojie; Wang, Qiang; Xue, Gang; Qian, Jianfei; Wang, Siqing; Yi, Qing

    2018-01-01

    Tumor-specific CD4+ T helper 9 (TH9) cells, so-called because of their production of the cytokine interleukin-9 (IL-9), are a powerful effector T cell subset for cancer immunotherapy. We found that pretreatment of naïve CD4+ T cells with IL-7 further enhanced their differentiation into TH9 cells and augmented their antitumor activity. IL-7 markedly increased the abundance of the histone acetyltransferase p300 by activating the STAT5 and PI3K-AKT-mTOR signaling pathways and promoting the acetylation of histones at the Il9 promoter. As a result, the transcriptional regulator Foxo1 was dephosphorylated and translocated to the nucleus, bound to the Il9 promoter, and induced the production of IL-9 protein. In contrast, Foxp1, which bound to the Il9 promoter in naïve CD4+ T cells and inhibited Il9 expression, was outcompeted for binding to the Il9 promoter by Foxo1 and translocated to the cytoplasm. Furthermore, forced expression of Foxo1 or a deficiency in Foxp1 in CD4+ T cells markedly increased the production of IL-9, whereas a deficiency in Foxo1 inhibited the ability of IL-7 to enhance the differentiation and antitumor activity of TH9 cells. Thus, we identified the roles of Foxo1 as a positive regulator and Foxp1 as a negative regulator of TH9 cell differentiation and antitumor activity, which may provide potential targets for cancer immunotherapy. PMID:29018172

  18. Quantitative Phosphoproteomic Study Reveals that Protein Kinase A Regulates Neural Stem Cell Differentiation Through Phosphorylation of Catenin Beta-1 and Glycogen Synthase Kinase 3β.

    Science.gov (United States)

    Wang, Shuxin; Li, Zheyi; Shen, Hongyan; Zhang, Zhong; Yin, Yuxin; Wang, Qingsong; Zhao, Xuyang; Ji, Jianguo

    2016-08-01

    Protein phosphorylation is central to the understanding of multiple cellular signaling pathways responsible for regulating the self-renewal and differentiation of neural stem cells (NSCs). Here we performed a large-scale phosphoproteomic analysis of rat fetal NSCs using strong cation exchange chromatography prefractionation and citric acid-assisted two-step enrichment with TiO2 strategy followed by nanoLC-MS/MS analysis. Totally we identified 32,546 phosphosites on 5,091 phosphoproteins, among which 23,945 were class I phosphosites, and quantified 16,000 sites during NSC differentiation. More than 65% of class I phosphosites were novel when compared with PhosphoSitePlus database. Quantification results showed that the early and late stage of NSC differentiation differ greatly. We mapped 69 changed phosphosites on 20 proteins involved in Wnt signaling pathway, including S552 on catenin beta-1 (Ctnnb1) and S9 on glycogen synthase kinase 3β (Gsk3β). Western blotting and real-time PCR results proved that Wnt signaling pathway plays critical roles in NSC fate determination. Furthermore, inhibition and activation of PKA dramatically affected the phosphorylation state of Ctnnb1 and Gsk3β, which regulates the differentiation of NSCs. Our data provides a valuable resource for studying the self-renewal and differentiation of NSCs. Stem Cells 2016;34:2090-2101. © 2016 AlphaMed Press.

  19. Nuclear Mechanics and Stem Cell Differentiation.

    Science.gov (United States)

    Mao, Xinjian; Gavara, Nuria; Song, Guanbin

    2015-12-01

    Stem cells are characterized by their self-renewal and multi-lineage differentiation potential. Stem cell differentiation is a prerequisite for the application of stem cells in regenerative medicine and clinical therapy. In addition to chemical stimulation, mechanical cues play a significant role in regulating stem cell differentiation. The integrity of mechanical sensors is necessary for the ability of cells to respond to mechanical signals. The nucleus, the largest and stiffest cellular organelle, interacts with the cytoskeleton as a key mediator of cell mechanics. Nuclear mechanics are involved in the complicated interactions of lamins, chromatin and nucleoskeleton-related proteins. Thus, stem cell differentiation is intimately associated with nuclear mechanics due to its indispensable role in mechanotransduction and mechanical response. This paper reviews several main contributions of nuclear mechanics, highlights the hallmarks of the nuclear mechanics of stem cells, and provides insight into the relationship between nuclear mechanics and stem cell differentiation, which may guide clinical applications in the future.

  20. Cdc42 is a key regulator of B cell differentiation and is required for antiviral humoral immunity

    DEFF Research Database (Denmark)

    Burbage, Marianne; Keppler, Selina J; Gasparrini, Francesca

    2015-01-01

    The small Rho GTPase Cdc42, known to interact with Wiskott-Aldrich syndrome (WAS) protein, is an important regulator of actin remodeling. Here, we show that genetic ablation of Cdc42 exclusively in the B cell lineage is sufficient to render mice unable to mount antibody responses. Indeed Cdc42-de...

  1. Single Low-Dose Radiation Induced Regulation of Keratinocyte Differentiation in Calcium-Induced HaCaT Cells

    OpenAIRE

    Hahn, Hyung Jin; Youn, Hae Jeong; Cha, Hwa Jun; Kim, Karam; An, Sungkwan; Ahn, Kyu Joong

    2016-01-01

    Background We are continually exposed to low-dose radiation (LDR) in the range 0.1 Gy from natural sources, medical devices, nuclear energy plants, and other industrial sources of ionizing radiation. There are three models for the biological mechanism of LDR: the linear no-threshold model, the hormetic model, and the threshold model. Objective We used keratinocytes as a model system to investigate the molecular genetic effects of LDR on epidermal cell differentiation. Methods To identify kera...

  2. P27Kip1, regulated by glycogen synthase kinase-3β, results in HMBA-induced differentiation of human gastric cancer cells

    International Nuclear Information System (INIS)

    Wei, Min; Gu, Qinlong; Wang, Zhiwei; Yao, Hongliang; Yang, Zhongyin; Zhang, Qing; Liu, Bingya; Yu, Yingyan; Su, Liping; Zhu, Zhenggang

    2011-01-01

    Gastric cancer is the second most common cause of global cancer-related mortality. Although dedifferentiation predicts poor prognosis in gastric cancer, the molecular mechanism underlying dedifferentiation, which could provide fundamental insights into tumor development and progression, has yet to be elucidated. Furthermore, the molecular mechanism underlying the effects of hexamethylene bisacetamide (HMBA), a recently discovered differentiation inducer, requires investigation and there are no reported studies concerning the effect of HMBA on gastric cancer. Based on the results of FACS analysis, the levels of proteins involved in the cell cycle or apoptosis were determined using western blotting after single treatments and sequential combinations of HMBA and LiCl. GSK-3β and proton pump were investigated by western blotting after up-regulating Akt expression by Ad-Akt infection. To investigate the effects of HMBA on protein localization and the activities of GSK-3β, CDK2 and CDK4, kinase assays, immunoprecipitation and western blotting were performed. In addition, northern blotting and RNase protection assays were carried out to determine the functional concentration of HMBA. HMBA increased p27Kip1 expression and induced cell cycle arrest associated with gastric epithelial cell differentiation. In addition, treating gastric-derived cells with HMBA induced G0/G1 arrest and up-regulation of the proton pump, a marker of gastric cancer differentiation. Moreover, treatment with HMBA increased the expression and activity of GSK-3β in the nucleus but not the cytosol. HMBA decreased CDK2 activity and induced p27Kip1 expression, which could be rescued by inhibition of GSK-3β. Furthermore, HMBA increased p27Kip1 binding to CDK2, and this was abolished by GSK-3β inhibition. The results presented herein suggest that GSK-3β functions by regulating p27Kip1 assembly with CDK2, thereby playing a critical role in G0/G1 arrest associated with HMBA-induced gastric epithelial

  3. Pulsed Electromagnetic Field Regulates MicroRNA 21 Expression to Activate TGF-β Signaling in Human Bone Marrow Stromal Cells to Enhance Osteoblast Differentiation

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    Nagarajan Selvamurugan

    2017-01-01

    Full Text Available Pulsed electromagnetic fields (PEMFs have been documented to promote bone fracture healing in nonunions and increase lumbar spinal fusion rates. However, the molecular mechanisms by which PEMF stimulates differentiation of human bone marrow stromal cells (hBMSCs into osteoblasts are not well understood. In this study the PEMF effects on hBMSCs were studied by microarray analysis. PEMF stimulation of hBMSCs’ cell numbers mainly affected genes of cell cycle regulation, cell structure, and growth receptors or kinase pathways. In the differentiation and mineralization stages, PEMF regulated preosteoblast gene expression and notably, the transforming growth factor-beta (TGF-β signaling pathway and microRNA 21 (miR21 were most highly regulated. PEMF stimulated activation of Smad2 and miR21-5p expression in differentiated osteoblasts, and TGF-β signaling was essential for PEMF stimulation of alkaline phosphatase mRNA expression. Smad7, an antagonist of the TGF-β signaling pathway, was found to be miR21-5p’s putative target gene and PEMF caused a decrease in Smad7 expression. Expression of Runx2 was increased by PEMF treatment and the miR21-5p inhibitor prevented the PEMF stimulation of Runx2 expression in differentiating cells. Thus, PEMF could mediate its effects on bone metabolism by activation of the TGF-β signaling pathway and stimulation of expression of miR21-5p in hBMSCs.

  4. Pituitary Gonadotropins, Prolactin and Growth Hormone Differentially Regulate AQP1 Expression in the Porcine Ovarian Follicular Cells

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    Mariusz T. Skowronski

    2017-12-01

    Full Text Available The present in vitro study analyzed whether the hormones that affect the ovarian follicular steroidogenesis process also participate in the regulation of AQP1 mRNA and protein expression. Granulosa (Gc and theca cells (Tc of medium and large porcine ovarian follicles were exposed to follicle-stimulating hormone (FSH, luteinizing hormone (LH, prolactin (PRL and growth hormone (GH for 24 h in separated cells and co-cultures of these cells. Real-time PCR, Western blotting, immunofluorescence and volumetric analysis were then performed. Gonadotropins, PRL and GH had a stimulatory impact on AQP1 mRNA and protein expression in Gc and Tc of medium and large ovarian cells. Moreover, swelling assays, in response to a hypotonic environment, demonstrated the functional presence of AQPs in porcine Gc and Tc. Immunofluorescence analysis showed that AQP1 protein was mainly localized in the perinuclear region of the cytoplasm, endosomes and cell membranes of Gc and Tc from medium and large follicles. It seems possible that AQP1 present in Gc and Tc cells may be implicated not only in the regulation of water homeostasis required for follicle development but also in cell proliferation and migration.

  5. Epigenetic regulation of the transcription factor Foxa2 directs differential elafin expression in melanocytes and melanoma cells

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Kyung Sook [Therapeutic Antibody Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon 305-806 (Korea, Republic of); Jo, Ji Yoon; Kim, Su Jin [Therapeutic Antibody Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon 305-806 (Korea, Republic of); Department of Functional Genomics, University of Science and Technology, Daejeon 305-333 (Korea, Republic of); Lee, Yangsoon [Therapeutic Antibody Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon 305-806 (Korea, Republic of); Bae, Jong Hwan [NeoPharm Co. Ltd., Daejeon 305-510 (Korea, Republic of); Chung, Young-Hwa [Department of Cogno-Mechatronics Engineering, BK21 Nanofusion Technology Team, Pusan National University, Busan 609-736 (Korea, Republic of); Koh, Sang Seok, E-mail: sskoh@kribb.re.kr [Therapeutic Antibody Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon 305-806 (Korea, Republic of); Department of Functional Genomics, University of Science and Technology, Daejeon 305-333 (Korea, Republic of)

    2011-04-29

    Highlights: {yields} Elafin expression is epigenetically silenced in human melanoma cells. {yields} Foxa2 expression in melanoma cells is silenced by promoter hypermethylation. {yields} Foxa2 directs activation of the elafin promoter in vivo. {yields} Foxa2 expression induces apoptosis of melanoma cells via elafin re-expression. -- Abstract: Elafin, a serine protease inhibitor, induces the intrinsic apoptotic pathway in human melanoma cells, where its expression is transcriptionally silenced. However, it remains unknown how the elafin gene is repressed in melanoma cells. We here demonstrate that elafin expression is modulated via epigenetically regulated expression of the transcription factor Foxa2. Treatment of melanoma cells with a DNA methyltransferase inhibitor induced elafin expression, which was specifically responsible for reduced proliferation and increased apoptosis. Suppression of Foxa2 transcription, mediated by DNA hypermethylation in its promoter region, was released in melanoma cells upon treatment with the demethylating agent. Luciferase reporter assays indicated that the Foxa2 binding site in the elafin promoter was critical for the activation of the promoter. Chromatin immunoprecipitation assays further showed that Foxa2 bound to the elafin promoter in vivo. Analyses of melanoma cells with varied levels of Foxa2 revealed a correlated expression between Foxa2 and elafin and the ability of Foxa2 to induce apoptosis. Our results collectively suggest that, in melanoma cells, Foxa2 expression is silenced and therefore elafin is maintained unexpressed to facilitate cell proliferation in the disease melanoma.

  6. TGF-β1 is Involved in Vitamin D-Induced Chondrogenic Differentiation of Bone Marrow-Derived Mesenchymal Stem Cells by Regulating the ERK/JNK Pathway

    Directory of Open Access Journals (Sweden)

    Xiaorui Jiang

    2017-08-01

    Full Text Available Background/Aims: Osteoarthritis (OA is characterized by degradation of cartilage, sole cell type of which is chondrocytes. Bone marrow-derived mesenchymal stem cells (BMSCs possess multipotency and can be directionally differentiated into chondrocytes under stimulation. This study was aimed to explore the possible roles of vitamin D and transforming growth factor-β1 (TGF-β1 in the chondrogenic differentiation of BMSCs. Methods: BMSCs were isolated from femurs and tibias of rats and characterized by flow cytometry. After stimulation with vitamin D, BMSC proliferation and migration were measured by Cell Counting Kit-8 (CCK-8 and Transwell assays, respectively. Chondrogenic differentiation was estimated through expression levels of specific markers by qRT-PCR and Western blot analysis. After stable transfection, the effects of aberrantly expressed TGF-β1 on vitamin D-induced alterations, including BMSC viability, migration and chondrogenic differentiation, were all evaluated utilizing CCK-8 assay, Transwell assay, qRT-PCR and Western blot analysis. Finally, the phosphorylation levels of key kinases in the extracellular signal-regulated kinase (ERK and c-Jun N-terminal kinase (JNK pathways were determined by Western blot analysis. Results: Vitamin D remarkably promoted BMSC viability, migration and chondrogenic differentiation. These alterations of BMSCs induced by vitamin D were reinforced by TGF-β1 overexpression while were reversed by TGF-β1 silencing. Additionally, the phosphorylation levels of ERK, JNK and c-Jun were enhanced by TGF-β1 overexpression but were reduced by TGF-β1 knockdown. Conclusion: Vitamin D promoted BMSC proliferation, migration and chondrogenic differentiation. TGF-β1 might be implicated in the vitamin D-induced alterations of BMSCs through regulating ERK/JNK pathway.

  7. NRF2 Signaling Negatively Regulates Phorbol-12-Myristate-13-Acetate (PMA-Induced Differentiation of Human Monocytic U937 Cells into Pro-Inflammatory Macrophages.

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    Min-Gu Song

    Full Text Available Blood monocytes are recruited to injured tissue sites and differentiate into macrophages, which protect against pathogens and repair damaged tissues. Reactive oxygen species (ROS are known to be an important contributor to monocytes' differentiation and macrophages' function. NF-E2-related factor 2 (NRF2, a transcription factor regulating cellular redox homeostasis, is known to be a critical modulator of inflammatory responses. We herein investigated the role of NRF2 in macrophage differentiation using the human monocytic U937 cell line and phorbol-12-myristate-13-acetate (PMA. In U937 cells with NRF2 silencing, PMA-stimulated cell adherence was significantly facilitated when compared to control U937 cells. Both transcript and protein levels for pro-inflammatory cytokines, including interleukine-1β (IL-1β, IL-6, and tumor necrosis factor-α (TNFα were highly elevated in PMA-stimulated NRF2-silenced U937 compared to the control. In addition, PMA-inducible secretion of monocyte chemotactic protein 1 (MCP-1 was significantly high in NRF2-silenced U937. As an underlying mechanism, we showed that NRF2-knockdown U937 retained high levels of cellular ROS and endoplasmic reticulum (ER stress markers expression; and subsequently, PMA-stimulated levels of Ca2+ and PKCα were greater in NRF2-knockdown U937 cells, which caused enhanced nuclear accumulation of nuclear factor-ҡB (NFҡB p50 and extracellular signal-regulated kinase (ERK-1/2 phosphorylation. Whereas the treatment of NRF2-silenced U937 cells with pharmacological inhibitors of NFҡB or ERK1/2 largely blocked PMA-induced IL-1β and IL-6 expression, indicating that these pathways are associated with cell differentiation. Taken together, our results suggest that the NRF2 system functions to suppress PMA-stimulated U937 cell differentiation into pro-inflammatory macrophages and provide evidence that the ROS-PKCα-ERK-NFҡB axis is involved in PMA-facilitated differentiation of NRF2-silenced U937

  8. Repression of TSC1/TSC2 mediated by MeCP2 regulates human embryo lung fibroblast cell differentiation and proliferation.

    Science.gov (United States)

    Wang, Yuanyuan; Chen, Chen; Deng, Ziyu; Bian, Erbao; Huang, Cheng; Lei, Ting; Lv, Xiongwen; Liu, Liping; Li, Jun

    2017-03-01

    Pulmonary fibrosis (PF) is a severe inflammatory disease with limited effective treatments. It is known that the transdifferentiation of human embryo lung fibroblast (HELF) cells from pulmonary fibroblasts into myofibroblasts, contributes to the progression of pulmonary fibrogenesis. The tuberous sclerosis proteins TSC1 and TSC2 are two key signaling factors which can suppress cell growth and proliferation. However, the roles of TSC1 and TSC2 in lung fibroblast are unclear. Here, we developed a PF model with bleomycin (BLM) in mice and conducted several simulation experiments in HELF cells. Our study shows that the expression of TSC1 and TSC2 in fibrotic mice lung was reduced and stimulation of HELF cells with TGF-β1 resulted in a down-regulation of TSC1 and TSC2. In addition, overexpression of TSC1 or TSC2 decreased cell proliferation and differentiation. Furthermore, we found that reduced expression of TSC1 and TSC2 caused by TGF-β1 is associated with the promoter methylation status of TSC1 and TSC2. MeCP2, controls an epigenetic pathway that promotes myofibroblast transdifferentiation and fibrosis. We found that expression of TSC1 and TSC2 can be repressed by MeCP2, which regulates HELF cell differentiation and proliferation as myofibroblasts and lead to PF ultimately. Copyright © 2016. Published by Elsevier B.V.

  9. Regulation of Th1 and Th17 cell differentiation and amelioration of experimental autoimmune encephalomyelitis by natural product compound berberine.

    Science.gov (United States)

    Qin, Xia; Guo, Bingshi T; Wan, Bing; Fang, Lei; Lu, Limin; Wu, Lili; Zang, Ying Qin; Zhang, Jingwu Z

    2010-08-01

    Berberine (BBR), an isoquinoline alkaloid derived from plants, is widely used as an anti-inflammatory remedy in traditional Chinese medicine. In this study, we showed that BBR was efficacious in the amelioration of experimental autoimmune encephalomyelitis (EAE) through novel regulatory mechanisms involving pathogenic Th1 and Th17 cells. BBR inhibited differentiation of Th17 cells and, to a lesser degree, Th1 cells through direct actions on the JAK/STAT pathway, whereas it had no effect on the relative number of CD4(+)Foxp3(+) regulatory T cells. In addition, BBR indirectly influenced Th17 and Th1 cell functions through its effect on the expression and function of costimulatory molecules and the production of IL-6, which was attributable to the inhibition of NF-kappaB activity in CD11b(+) APCs. BBR treatment completely abolished the encephalitogenicity of MOG(35-55)-reactive Th17 cells in an adoptive transfer EAE model, and the same treatment significantly inhibited the ability of MOG(35-55)-reactive Th1 cells to induce EAE. This study provides new evidence that natural compounds, such as BBR, are of great value in the search for novel anti-inflammatory agents and therapeutic targets for autoimmune diseases.

  10. Osteoblastic cells: differentiation and trans-differentiation

    DEFF Research Database (Denmark)

    Kassem, Moustapha; Abdallah, Basem; Saeed, Hamid

    2008-01-01

    The osteoblast is the bone forming cell and is derived from mesenchymal stem cells (MSC) present among the bone marrow stroma. MSC are capable of multi-lineage differentiation into mesoderm-type cells such as osteoblasts and adipocytes. Understanding the mechanisms underlying osteoblast different...

  11. Two-way regulation between cells and aligned collagen fibrils: local 3D matrix formation and accelerated neural differentiation of human decidua parietalis placental stem cells.

    Science.gov (United States)

    Li, Wen; Zhu, Bofan; Strakova, Zuzana; Wang, Rong

    2014-08-08

    It has been well established that an aligned matrix provides structural and signaling cues to guide cell polarization and cell fate decision. However, the modulation role of cells in matrix remodeling and the feedforward effect on stem cell differentiation have not been studied extensively. In this study, we report on the concerted changes of human decidua parietalis placental stem cells (hdpPSCs) and the highly ordered collagen fibril matrix in response to cell-matrix interaction. With high-resolution imaging, we found the hdpPSCs interacted with the matrix by deforming the cell shape, harvesting the nearby collagen fibrils, and reorganizing the fibrils around the cell body to transform a 2D matrix to a localized 3D matrix. Such a unique 3D matrix prompted high expression of β-1 integrin around the cell body that mediates and facilitates the stem cell differentiation toward neural cells. The study offers insights into the coordinated, dynamic changes at the cell-matrix interface and elucidates cell modulation of its matrix to establish structural and biochemical cues for effective cell growth and differentiation. Copyright © 2014 Elsevier Inc. All rights reserved.

  12. PR-957, a selective inhibitor of immunoproteasome subunit low-MW polypeptide 7, attenuates experimental autoimmune neuritis by suppressing Th17-cell differentiation and regulating cytokine production.

    Science.gov (United States)

    Liu, Haijie; Wan, Chunxiao; Ding, Yanan; Han, Ranran; He, Yating; Xiao, Jinting; Hao, Junwei

    2017-04-01

    Experimental autoimmune neuritis (EAN) is a CD4 + T-cell-mediated autoimmune inflammatory demyelinating disease of the peripheral nervous system. It has been replicated in an animal model of human inflammatory demyelinating polyradiculoneuropathy, Guillain-Barré syndrome. In this study, we evaluated the therapeutic efficacy of a selective inhibitor of the immunoproteasome subunit, low-MW polypeptide 7 (PR-957) in rats with EAN. Our results showed that PR-957 significantly delayed onset day, reduced severity and shortened duration of EAN, and alleviated demyelination and inflammatory infiltration in sciatic nerves. In addition to significantly regulating expression of the cytokine profile, PR-957 treatment down-regulated the proportion of proinflammatory T-helper (T h )17 cells in sciatic nerves and spleens of rats with EAN. Data presented show the role of PR-957 in the signal transducer and activator of transcription 3 (STAT3) pathway. PR-957 not only decreased expression of IL-6 and IL-23 but also led to down-regulation of STAT3 phosphorylation in CD4 + T cells. Regulation of the STAT3 pathway led to a reduction in retinoid-related orphan nuclear receptor γ t and IL-17 production. Furthermore, reduction of STAT3 phosphorylation may have directly suppressed T h 17-cell differentiation. Therefore, our study demonstrates that PR-957 could potently alleviate inflammation in rats with EAN and that it may be a likely candidate for treating Guillain-Barré syndrome.-Liu, H., Wan, C., Ding, Y., Han, R., He, Y., Xiao, J., Hao, J. PR-957, a selective inhibitor of immunoproteasome subunit low-MW polypeptide 7, attenuates experimental autoimmune neuritis by suppressing T h 17-cell differentiation and regulating cytokine production. © FASEB.

  13. Laminin isoforms differentially regulate adhesion, spreading, proliferation, and ERK activation of β1 integrin-null cells

    International Nuclear Information System (INIS)

    Kikkawa, Yamato; Yu, Hao; Genersch, Elke; Sanzen, Noriko; Sekiguchi, Kiyotoshi; Faessler, Reinhard; Campbell, Kevin P.; Talts, Jan F.; Ekblom, Peter

    2004-01-01

    The presence of many laminin receptors of the β1 integrin family on most cells makes it difficult to define the biological functions of other major laminin receptors such as integrin α6β4 and dystroglycan. We therefore tested the binding of a β1 integrin-null cell line GD25 to four different laminin variants. The cells were shown to produce dystroglycan, which based on affinity chromatography bound to laminin-1, -2/4, and -10/11, but not to laminin-5. The cells also expressed the integrin α6Aβ4A variant. GD25 β1 integrin-null cells are known to bind poorly to laminin-1, but we demonstrate here that these cells bind avidly to laminin-2/4, -5, and -10/11. The initial binding at 20 min to each of these laminins could be inhibited by an integrin α6 antibody, but not by a dystroglycan antibody. Hence, integrin α6Aβ4A of GD25 cells was identified as a major receptor for initial GD25 cell adhesion to three out of four tested laminin isoforms. Remarkably, cell adhesion to laminin-5 failed to promote cell spreading, proliferation, and extracellular signal-regulated kinase (ERK) activation, whereas all these responses occurred in response to adhesion to laminin-2/4 or -10/11. The data establish GD25 cells as useful tools to define the role integrin α6Aβ4A and suggest that laminin isoforms have distinctly different capacities to promote cell adhesion and signaling via integrin α6Aβ4A

  14. Cocaine- and amphetamine-regulated transcript promotes the differentiation of mouse bone marrow-derived mesenchymal stem cells into neural cells

    Directory of Open Access Journals (Sweden)

    Jin Jiali

    2011-07-01

    Full Text Available Abstract Background Neural tissue has limited potential to self-renew after neurological damage. Cell therapy using BM-MSCs (bone marrow mesenchymal stromal cells seems like a promising approach for the treatment of neurological diseases. However, the neural differentiation of stem cells influenced by massive factors and interactions is not well studied at present. Results In this work, we isolated and identified MSCs from mouse bone marrow. Co-cultured with CART (0.4 nM for six days, BM-MSCs were differentiated into neuron-like cells by the observation of optical microscopy. Immunofluorescence demonstrated that the differentiated BM-MSCs expressed neural specific markers including MAP-2, Nestin, NeuN and GFAP. In addition, NeuN positive cells could co-localize with TH or ChAT by double-labled immunofluorescence and Nissl bodies were found in several differentiated cells by Nissl stain. Furthermore, BDNF and NGF were increased by CART using RT-PCR. Conclusion This study demonstrated that CART could promote the differentiation of BM-MSCs into neural cells through increasing neurofactors, including BNDF and NGF. Combined application of CART and BM-MSCs may be a promising cell-based therapy for neurological diseases.

  15. Genome-Wide Studies Reveal that H3K4me3 Modification in Bivalent Genes Is Dynamically Regulated during the Pluripotent Cell Cycle and Stabilized upon Differentiation.

    Science.gov (United States)

    Grandy, Rodrigo A; Whitfield, Troy W; Wu, Hai; Fitzgerald, Mark P; VanOudenhove, Jennifer J; Zaidi, Sayyed K; Montecino, Martin A; Lian, Jane B; van Wijnen, André J; Stein, Janet L; Stein, Gary S

    2016-02-15

    Stem cell phenotypes are reflected by posttranslational histone modifications, and this chromatin-related memory must be mitotically inherited to maintain cell identity through proliferative expansion. In human embryonic stem cells (hESCs), bivalent genes with both activating (H3K4me3) and repressive (H3K27me3) histone modifications are essential to sustain pluripotency. Yet, the molecular mechanisms by which this epigenetic landscape is transferred to progeny cells remain to be established. By mapping genomic enrichment of H3K4me3/H3K27me3 in pure populations of hESCs in G2, mitotic, and G1 phases of the cell cycle, we found striking variations in the levels of H3K4me3 through the G2-M-G1 transition. Analysis of a representative set of bivalent genes revealed that chromatin modifiers involved in H3K4 methylation/demethylation are recruited to bivalent gene promoters in a cell cycle-dependent fashion. Interestingly, bivalent genes enriched with H3K4me3 exclusively during mitosis undergo the strongest upregulation after induction of differentiation. Furthermore, the histone modification signature of genes that remain bivalent in differentiated cells resolves into a cell cycle-independent pattern after lineage commitment. These results establish a new dimension of chromatin regulation important in the maintenance of pluripotency. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  16. Extremely Low-Frequency Electromagnetic Fields Promote In Vitro Neuronal Differentiation and Neurite Outgrowth of Embryonic Neural Stem Cells via Up-Regulating TRPC1

    Science.gov (United States)

    Ma, Qinlong; Chen, Chunhai; Deng, Ping; Zhu, Gang; Lin, Min; Zhang, Lei; Xu, Shangcheng; He, Mindi; Lu, Yonghui; Duan, Weixia; Pi, Huifeng; Cao, Zhengwang; Pei, Liping; Li, Min; Liu, Chuan; Zhang, Yanwen; Zhong, Min; Zhou, Zhou; Yu, Zhengping

    2016-01-01

    Exposure to extremely low-frequency electromagnetic fields (ELF-EMFs) can enhance hippocampal neurogenesis in adult mice. However, little is focused on the effects of ELF-EMFs on embryonic neurogenesis. Here, we studied the potential effects of ELF-EMFs on embryonic neural stem cells (eNSCs). We exposed eNSCs to ELF-EMF (50 Hz, 1 mT) for 1, 2, and 3 days with 4 hours per day. We found that eNSC proliferation and maintenance were significantly enhanced after ELF-EMF exposure in proliferation medium. ELF-EMF exposure increased the ratio of differentiated neurons and promoted the neurite outgrowth of eNSC-derived neurons without influencing astrocyes differentiation and the cell apoptosis. In addition, the expression of the proneural genes, NeuroD and Ngn1, which are crucial for neuronal differentiation and neurite outgrowth, was increased after ELF-EMF exposure. Moreover, the expression of transient receptor potential canonical 1 (TRPC1) was significantly up-regulated accompanied by increased the peak amplitude of intracellular calcium level induced by ELF-EMF. Furthermore, silencing TRPC1 expression eliminated the up-regulation of the proneural genes and the promotion of neuronal differentiation and neurite outgrowth induced by ELF-EMF. These results suggest that ELF-EMF exposure promotes the neuronal differentiation and neurite outgrowth of eNSCs via up-regulation the expression of TRPC1 and proneural genes (NeuroD and Ngn1). These findings also provide new insights in understanding the effects of ELF-EMF exposure on embryonic brain development. PMID:26950212

  17. Fibroblast growth factor 2 inhibits up-regulation of bone morphogenic proteins and their receptors during osteoblastic differentiation of human mesenchymal stem cells

    Energy Technology Data Exchange (ETDEWEB)

    Biver, Emmanuel, E-mail: ebiver@yahoo.fr [Physiopathology of Inflammatory Bone Diseases, EA 4490, University Lille North of France, Quai Masset, Bassin Napoleon, BP120, 62327 Boulogne sur Mer (France); Department of Rheumatology, Lille University Hospital, Roger Salengro Hospital, 59037 Lille cedex (France); Service of Bone Diseases, Department of Internal Medicine Specialties, University Hospital of Geneva, CH-1211 Geneva 14 (Switzerland); Soubrier, Anne-Sophie [Physiopathology of Inflammatory Bone Diseases, EA 4490, University Lille North of France, Quai Masset, Bassin Napoleon, BP120, 62327 Boulogne sur Mer (France); Department of Rheumatology, Lille University Hospital, Roger Salengro Hospital, 59037 Lille cedex (France); Thouverey, Cyril [Service of Bone Diseases, Department of Internal Medicine Specialties, University Hospital of Geneva, CH-1211 Geneva 14 (Switzerland); Cortet, Bernard [Physiopathology of Inflammatory Bone Diseases, EA 4490, University Lille North of France, Quai Masset, Bassin Napoleon, BP120, 62327 Boulogne sur Mer (France); Department of Rheumatology, Lille University Hospital, Roger Salengro Hospital, 59037 Lille cedex (France); Broux, Odile [Physiopathology of Inflammatory Bone Diseases, EA 4490, University Lille North of France, Quai Masset, Bassin Napoleon, BP120, 62327 Boulogne sur Mer (France); Caverzasio, Joseph [Service of Bone Diseases, Department of Internal Medicine Specialties, University Hospital of Geneva, CH-1211 Geneva 14 (Switzerland); Hardouin, Pierre [Physiopathology of Inflammatory Bone Diseases, EA 4490, University Lille North of France, Quai Masset, Bassin Napoleon, BP120, 62327 Boulogne sur Mer (France)

    2012-11-02

    Highlights: Black-Right-Pointing-Pointer FGF modulates BMPs pathway in HMSCs by down-regulating BMP/BMPR expression. Black-Right-Pointing-Pointer This effect is mediated by ERK and JNK MAPKs pathways. Black-Right-Pointing-Pointer Crosstalk between FGF and BMPs must be taken into account in skeletal bioengineering. Black-Right-Pointing-Pointer It must also be considered in the use of recombinant BMPs in orthopedic and spine surgeries. -- Abstract: Understanding the interactions between growth factors and bone morphogenic proteins (BMPs) signaling remains a crucial issue to optimize the use of human mesenchymal stem cells (HMSCs) and BMPs in therapeutic perspectives and bone tissue engineering. BMPs are potent inducers of osteoblastic differentiation. They exert their actions via BMP receptors (BMPR), including BMPR1A, BMPR1B and BMPR2. Fibroblast growth factor 2 (FGF2) is expressed by cells of the osteoblastic lineage, increases their proliferation and is secreted during the healing process of fractures or in surgery bone sites. We hypothesized that FGF2 might influence HMSC osteoblastic differentiation by modulating expressions of BMPs and their receptors. BMP2, BMP4, BMPR1A and mainly BMPR1B expressions were up-regulated during this differentiation. FGF2 inhibited HMSCs osteoblastic differentiation and the up-regulation of BMPs and BMPR. This effect was prevented by inhibiting the ERK or JNK mitogen-activated protein kinases which are known to be activated by FGF2. These data provide a mechanism explaining the inhibitory effect of FGF2 on osteoblastic differentiation of HMSCs. These crosstalks between growth and osteogenic factors should be considered in the use of recombinant BMPs in therapeutic purpose of fracture repair or skeletal bioengineering.

  18. Differential regulation of histamine- and bradykinin-stimulated phospholipase C in adrenal chromaffin cells: evidence for involvement of different protein kinase C isoforms.

    Science.gov (United States)

    Sena, C M; Rosário, L M; Parker, P J; Patel, V; Boarder, M R

    1996-03-01

    In this report we investigate the isoforms of protein kinase C (PKC) present in cultured adrenal chromaffin cells with respect to their modulation by treatment with phorbol ester and their possible differential involvement in the regulation of responses to histamine and bradykinin. The presence of individual isoforms of PKC was investigated by using eight isoform specific antisera, as a result of which PKC-alpha, epsilon, and zeta were identified. To characterize down-regulation of these enzymes, cells were incubated for 6-48 h with 1 microM phorbol myristate acetate (PMA). PKC-epsilon down-regulated more rapidly than PKC-alpha. At 12 h, PMA pretreatment, for example, PKC-epsilon was maximally down-regulated (23 +/- 4% of controls), whereas PKC-alpha was unchanged. PKC-alpha showed partial down-regulation by 24 h of PMA pretreatment. PKC-zeta did not down-regulate at any of the times tested. Translocation from cytosol to membrane in response to PMA was also more rapid for PKC-epsilon than for PKC-alpha. The accumulation of total 3H-inositol (poly) phosphates in response to bradykinin or histamine was essentially abolished by prior treatment with 10-min PMA treatment (1 microM). However, with 12-h exposure to PMA, the bradykinin response was restored to the level seen with no prior PMA exposure. The histamine response showed no recovery by 12 h of PMA, but showed partial recovery by 24 h of PMA pretreatment. These observations showed that the restoration of the response to bradykinin corresponds to the loss of PKC-epsilon, whereas the restoration of the histamine response corresponds to the loss of PKC-alpha. This picture was confirmed with further studies on cytosolic Ca2+. The results show that chromaffin cells exhibit an unusual pattern of down-regulation of PKC isoforms on prolonged exposure to PMA, and that there is a differential effect of exposure to PMA on the histamine and bradykinin responses, suggesting that different PLC-linked receptors in chromafin

  19. Monocyte to macrophage differentiation-associated (MMD) targeted by miR-140-5p regulates tumor growth in non-small cell lung cancer

    International Nuclear Information System (INIS)

    Li, Weina; He, Fei

    2014-01-01

    Highlights: • Expression of MMD is increased in lung cancer tissues. • Knockdown of MMD inhibits growth of A549 and LLC cells in vitro and in vivo. • MMD is a direct functional target of miR-140-5p. • MiR-140-5p/MMD axis regulates Erk1/2 signaling. - Abstract: Monocyte to macrophage differentiation-associated (MMD) is identified in macrophages as a gene associated with the differentiation from monocytes to macrophages. Recent microarray analysis for non-small cell lung cancer (NSCLC) suggests that MMD is an important signature associated with relapse and survival among patients with NSCLC. Therefore, we speculate that MMD likely plays a role in lung cancer. In this study, we found that the protein level of MMD was increased in lung cancer compared to benign lung tissues, and knockdown of MMD inhibited the growth of A549 and Lewis lung cancer cells (LLC) in vitro and in vivo. Integrated analysis demonstrated that MMD was a direct functional target of miR-140-5p. Furthermore, we found that miR-140-5p/MMD axis could affect the cell proliferation of lung cancer cells by regulating Erk signaling. Together, our results highlight the significance of miR-140-5p/MMD axis in lung cancer, and miR-140-5p/MMD axis could serve as new molecular targets for the therapy against lung cancer

  20. Human mesenchymal stem cell proliferation is regulated by PGE2 through differential activation of cAMP-dependent protein kinase isoforms

    International Nuclear Information System (INIS)

    Kleiveland, Charlotte Ramstad; Kassem, Moustapha; Lea, Tor

    2008-01-01

    The conditions used for in vitro differentiation of hMSCs contain substances that affect the activity and expression of cyclooxygenase enzymes (COX1/COX2) and thereby the synthesis of prostanoids. hMSC constitutively produce PGE2 when cultivated in vitro. In this study we have investigated effects of PGE2 on proliferation of hMSC. We here demonstrate that one of the main control molecules in the Wnt pathway, GSK-3β, is phosphorylated at the negative regulatory site ser-9 after treating the cells with PGE2. This phosphorylation is mediated by elevation of cAMP and subsequent activation of PKA. Furthermore, PGE2 treatment leads to enhanced nuclear translocation of β-catenin, thus influencing cell proliferation. The presence of two PKA isoforms, types I and II, prompted us to investigate their individual contribution in PGE2-mediated regulation of proliferation. Specific activation of PKA type II with synthetic cAMP analogues, resulted in enhancement of proliferation. On the other side, we found that treatment of hMSC with high concentrations of PGE2 inhibited cell proliferation by arresting the cells in G 0 /G 1 phase, an effect we found to be mediated by PKA I. Hence, the two different PKA isoforms seem to have opposing functions in the regulation of proliferation and differentiation in these cells

  1. Differentially expressed miRNAs after GnRH treatment and their potential roles in FSH regulation in porcine anterior pituitary cell.

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    Rui-Song Ye

    Full Text Available Hypothalamic gonadotropin-releasing hormone (GnRH is a major regulator of follicle-stimulating hormone (FSH secretion in gonadotrope cell in the anterior pituitary gland. microRNAs (miRNAs are small RNA molecules that control gene expression by imperfect binding to the 3'-untranslated region (3'-UTR of mRNA at the post-transcriptional level. It has been proven that miRNAs play an important role in hormone response and/or regulation. However, little is known about miRNAs in the regulation of FSH secretion. In this study, primary anterior pituitary cells were treated with 100 nM GnRH. The supernatant of pituitary cell was collected for FSH determination by enzyme-linked immunosorbent assay (ELISA at 3 hours and 6 hours post GnRH treatment respectively. Results revealed that GnRH significantly promoted FSH secretion at 3 h and 6 h post-treatment by 1.40-fold and 1.80-fold, respectively. FSHβ mRNA at 6 h post GnRH treatment significantly increased by 1.60-fold. At 6 hours, cells were collected for miRNA expression profile analysis using MiRCURY LNA Array and quantitative PCR (qPCR. Consequently, 21 up-regulated and 10 down-regulated miRNAs were identified, and qPCR verification of 10 randomly selected miRNAs showed a strong correlation with microarray results. Chromosome location analysis indicated that 8 miRNAs were mapped to chromosome 12 and 4 miRNAs to chromosome X. Target and pathway analysis showed that some miRNAs may be associated with GnRH regulation pathways. In addition, In-depth analysis indicated that 10 up-regulated and 3 down-regulated miRNAs probably target FSHβ mRNA 3'-UTR directly, including miR-361-3p, a highly conserved X-linked miRNA. Most importantly, functional experimental results showed that miR-361-3p was involved in FSH secretion regulation, and up-regulated miR-361-3p expression inhibited FSH secretion, while down-regulated miR-361-3p expression promoted FSH secretion in pig pituitary cell model. These differentially

  2. Keratin 8/18 regulation of glucose metabolism in normal versus cancerous hepatic cells through differential modulation of hexokinase status and insulin signaling

    Energy Technology Data Exchange (ETDEWEB)

    Mathew, Jasmin; Loranger, Anne; Gilbert, Stéphane [Centre de recherche en cancérologie de l' Université Laval and Centre de recherche du CHUQ (L' Hôtel-Dieu de Québec), 9 McMahon, Québec, Qc, Canada G1R 2J6 (Canada); Faure, Robert [Département de Pédiatrie, Université Laval and Centre de recherche du CHUQ (Centre Mère-Enfant), Québec, Qc, Canada G1V 4G2 (Canada); Marceau, Normand, E-mail: normand.marceau@crhdq.ulaval.ca [Centre de recherche en cancérologie de l' Université Laval and Centre de recherche du CHUQ (L' Hôtel-Dieu de Québec), 9 McMahon, Québec, Qc, Canada G1R 2J6 (Canada)

    2013-02-15

    As differentiated cells, hepatocytes primarily metabolize glucose for ATP production through oxidative phosphorylation of glycolytic pyruvate, whereas proliferative hepatocellular carcinoma (HCC) cells undergo a metabolic shift to aerobic glycolysis despite oxygen availability. Keratins, the intermediate filament (IF) proteins of epithelial cells, are expressed as pairs in a lineage/differentiation manner. Hepatocyte and HCC (hepatoma) cell IFs are made solely of keratins 8/18 (K8/K18), thus providing models of choice to address K8/K18 IF functions in normal and cancerous epithelial cells. Here, we demonstrate distinctive increases in glucose uptake, glucose-6-phosphate formation, lactate release, and glycogen formation in K8/K18 IF-lacking hepatocytes and/or hepatoma cells versus their respective IF-containing counterparts. We also show that the K8/K18-dependent glucose uptake/G6P formation is linked to alterations in hexokinase I/II/IV content and localization at mitochondria, with little effect on GLUT1 status. In addition, we find that the insulin-stimulated glycogen formation in normal hepatocytes involves the main PI-3 kinase-dependent signaling pathway and that the K8/K18 IF loss makes them more efficient glycogen producers. In comparison, the higher insulin-dependent glycogen formation in K8/K18 IF-lacking hepatoma cells is associated with a signaling occurring through a mTOR-dependent pathway, along with an augmentation in cell proliferative activity. Together, the results uncover a key K8/K18 regulation of glucose metabolism in normal and cancerous hepatic cells through differential modulations of mitochondrial HK status and insulin-mediated signaling.

  3. Regulation of a TGF-β1-CD147 self-sustaining network in the differentiation plasticity of hepatocellular carcinoma cells.

    Science.gov (United States)

    Wu, J; Lu, M; Li, Y; Shang, Y-K; Wang, S-J; Meng, Y; Wang, Z; Li, Z-S; Chen, H; Chen, Z-N; Bian, H

    2016-10-20

    Cellular plasticity has an important role in the progression of hepatocellular carcinoma (HCC). In this study, the involvement of a TGF-β1-CD147 self-sustaining network in the regulation of the dedifferentiation progress was fully explored in HCC cell lines, hepatocyte-specific basigin/CD147-knockout mice and human HCC tissues. We demonstrated that TGF-β1 stimulation upregulated CD147 expression and mediated the dedifferentiation of HCC cells, whereas all-trans-retinoic acid induced the downregulation of CD147 and promoted differentiation in HCC cells. Overexpression of CD147 induced the dedifferentiation and enhanced the malignancy of HCC cells, and increased the transcriptional expression of TGF-β1 by activating β-catenin. CD147-induced matrix metalloproteinase (MMP) production activated pro-TGF-β1. The activated TGF-β1 signaling subsequently repressed the HNF4α expression via Smad-Snail1 signaling and enhanced the dedifferentiation progress. Hepatocyte-specific basigin/CD147-knockout mice decreased the susceptibility to N-nitrosodiethylamine-induced tumorigenesis by suppressing TGF-β1-CD147 signaling and inhibiting dedifferentiation in hepatocytes during tumor progression. CD147 was positively correlated with TGF-β1 and negatively correlated with HNF4α in human HCC tissues. Positive CD147 staining and lower HNF4α levels in tumor tissues were significantly associated with poor survival of patients with HCC. The overexpression of HNF4α and Smad7 and the deletion of CD147 by lentiviral vectors jointly reprogrammed the expression profile of hepatocyte markers and attenuated malignant properties including proliferation, cell survival and tumor growth of HCC cells. Our results highlight the important role of the TGF-β1-CD147 self-sustaining network in driving HCC development by regulating differentiation plasticity, which provides a strong basis for further investigations of the differentiation therapy of HCC targeting TGF-β1 and CD147.

  4. Differential Regulation of cGMP Signaling in Human Melanoma Cells at Altered Gravity: Simulated Microgravity Down-Regulates Cancer-Related Gene Expression and Motility

    Science.gov (United States)

    Ivanova, Krassimira; Eiermann, Peter; Tsiockas, Wasiliki; Hemmersbach, Ruth; Gerzer, Rupert

    2018-03-01

    Altered gravity is known to affect cellular function by changes in gene expression and cellular signaling. The intracellular signaling molecule cyclic guanosine-3',5'-monophosphate (cGMP), a product of guanylyl cyclases (GC), e.g., the nitric oxide (NO)-sensitive soluble GC (sGC) or natriuretic peptide-activated GC (GC-A/GC-B), is involved in melanocyte response to environmental stress. NO-sGC-cGMP signaling is operational in human melanocytes and non-metastatic melanoma cells, whereas up-regulated expression of GC-A/GC-B and inducible NO synthase (iNOS) are found in metastatic melanoma cells, the deadliest skin cancer. Here, we investigated the effects of altered gravity on the mRNA expression of NOS isoforms, sGC, GC-A/GC-B and multidrug resistance-associated proteins 4/5 (MRP4/MRP5) as selective cGMP exporters in human melanoma cells with different metastatic potential and pigmentation. A specific centrifuge (DLR, Cologne Germany) was used to generate hypergravity (5 g for 24 h) and a fast-rotating 2-D clinostat (60 rpm) to simulate microgravity values ≤ 0.012 g for 24 h. The results demonstrate that hypergravity up-regulates the endothelial NOS-sGC-MRP4/MRP5 pathway in non-metastatic melanoma cells, but down-regulates it in simulated microgravity when compared to 1 g. Additionally, the suppression of sGC expression and activity has been suggested to correlate inversely to tumor aggressiveness. Finally, hypergravity is ineffective in highly metastatic melanoma cells, whereas simulated microgravity down-regulates predominantly the expression of the cancer-related genes iNOS and GC-A/GC-B (shown additionally on protein levels) as well as motility in comparison to 1 g. The results suggest that future studies in real microgravity can benefit from considering GC-cGMP signaling as possible factor for melanocyte transformation.

  5. Developmental regulation of nucleolus size during Drosophila eye differentiation.

    Directory of Open Access Journals (Sweden)

    Nicholas E Baker

    Full Text Available When cell cycle withdrawal accompanies terminal differentiation, biosynthesis and cellular growth are likely to change also. In this study, nucleolus size was monitored during cell fate specification in the Drosophila eye imaginal disc using fibrillarin antibody labeling. Nucleolus size is an indicator of ribosome biogenesis and can correlate with cellular growth rate. Nucleolar size was reduced significantly during cell fate specification and differentiation, predominantly as eye disc cells entered a cell cycle arrest that preceded cell fate specification. This reduction in nucleolus size required Dpp and Hh signaling. A transient enlargement of the nucleolus accompanied cell division in the Second Mitotic Wave. Nucleoli continued to diminish in postmitotic cells following fate specification. These results suggest that cellular growth is regulated early in the transition from proliferating progenitor cells to terminal cell fate specification, contemporary with regulation of the cell cycle, and requiring the same extracellular signals.

  6. Developmental regulation of nucleolus size during Drosophila eye differentiation.

    Science.gov (United States)

    Baker, Nicholas E

    2013-01-01

    When cell cycle withdrawal accompanies terminal differentiation, biosynthesis and cellular growth are likely to change also. In this study, nucleolus size was monitored during cell fate specification in the Drosophila eye imaginal disc using fibrillarin antibody labeling. Nucleolus size is an indicator of ribosome biogenesis and can correlate with cellular growth rate. Nucleolar size was reduced significantly during cell fate specification and differentiation, predominantly as eye disc cells entered a cell cycle arrest that preceded cell fate specification. This reduction in nucleolus size required Dpp and Hh signaling. A transient enlargement of the nucleolus accompanied cell division in the Second Mitotic Wave. Nucleoli continued to diminish in postmitotic cells following fate specification. These results suggest that cellular growth is regulated early in the transition from proliferating progenitor cells to terminal cell fate specification, contemporary with regulation of the cell cycle, and requiring the same extracellular signals.

  7. Differential transcriptional regulation of IL-8 expression by human airway epithelial cells exposed to diesel exhaust particles

    International Nuclear Information System (INIS)

    Tal, Tamara L.; Simmons, Steven O.; Silbajoris, Robert; Dailey, Lisa; Cho, Seung-Hyun; Ramabhadran, Ram; Linak, William; Reed, William; Bromberg, Philip A.; Samet, James M.

    2010-01-01

    Exposure to diesel exhaust particles (DEP) induces inflammatory signaling characterized by MAP kinase-mediated activation of NFkB and AP-1 in vitro and in bronchial biopsies obtained from human subjects exposed to DEP. NFkB and AP-1 activation results in the upregulation of genes involved in promoting inflammation in airway epithelial cells, a principal target of inhaled DEP. IL-8 is a proinflammatory chemokine expressed by the airway epithelium in response to environmental pollutants. The mechanism by which DEP exposure induces IL-8 expression is not well understood. In the current study, we sought to determine whether DEP with varying organic content induces IL-8 expression in lung epithelial cells, as well as, to develop a method to rapidly evaluate the upstream mechanism(s) by which DEP induces IL-8 expression. Exposure to DEP with varying organic content differentially induced IL-8 expression and IL-8 promoter activity human airway epithelial cells. Mutational analysis of the IL-8 promoter was also performed using recombinant human cell lines expressing reporters linked to the mutated promoters. Treatment with a low organic-containing DEP stimulated IL-8 expression by a mechanism that is predominantly NFkB-dependent. In contrast, exposure to high organic-containing DEP induced IL-8 expression independently of NFkB through a mechanism that requires AP-1 activity. Our study reveals that exposure to DEP of varying organic content induces proinflammatory gene expression through multiple specific mechanisms in human airway epithelial cells. The approaches used in the present study demonstrate the utility of a promoter-reporter assay ensemble for identifying transcriptional pathways activated by pollutant exposure.

  8. Antitumor and chemosensitizing action of dichloroacetate implicates modulation of tumor microenvironment: A role of reorganized glucose metabolism, cell survival regulation and macrophage differentiation

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Ajay; Kant, Shiva; Singh, Sukh Mahendra, E-mail: sukhmahendrasingh@yahoo.com

    2013-11-15

    Targeting of tumor metabolism is emerging as a novel therapeutic strategy against cancer. Dichloroacetate (DCA), an inhibitor of pyruvate dehydrogenase kinase (PDK), has been shown to exert a potent tumoricidal action against a variety of tumor cells. The main mode of its antineoplastic action implicates a shift of glycolysis to oxidative metabolism of glucose, leading to generation of cytotoxic reactive oxygen intermediates. However, the effect of DCA on tumor microenvironment, which in turn regulates tumor cell survival; remains speculative to a large extent. It is also unclear if DCA can exert any modulatory effect on the process of hematopoiesis, which is in a compromised state in tumor-bearing hosts undergoing chemotherapy. In view of these lacunas, the present study was undertaken to investigate the so far unexplored aspects with respect to the molecular mechanisms of DCA-dependent tumor growth retardation and chemosensitization. BALB/c mice were transplanted with Dalton's lymphoma (DL) cells, a T cell lymphoma of spontaneous origin, followed by administration of DCA with or without cisplatin. DCA-dependent tumor regression and chemosensitization to cisplatin was found to be associated with altered repertoire of key cell survival regulatory molecules, modulated glucose metabolism, accompanying reconstituted tumor microenvironment with respect to pH homeostasis, cytokine balance and alternatively activated TAM. Moreover, DCA administration also led to an alteration in the MDR phenotype of tumor cells and myelopoietic differentiation of macrophages. The findings of this study shed a new light with respect to some of the novel mechanisms underlying the antitumor action of DCA and thus may have immense clinical applications. - Highlights: • DCA modulates tumor progression and chemoresistance. • DCA alters molecules regulating cell survival, glucose metabolism and MDR. • DCA reconstitutes biophysical and cellular composition of tumor microenvironment.

  9. Antitumor and chemosensitizing action of dichloroacetate implicates modulation of tumor microenvironment: A role of reorganized glucose metabolism, cell survival regulation and macrophage differentiation

    International Nuclear Information System (INIS)

    Kumar, Ajay; Kant, Shiva; Singh, Sukh Mahendra

    2013-01-01

    Targeting of tumor metabolism is emerging as a novel therapeutic strategy against cancer. Dichloroacetate (DCA), an inhibitor of pyruvate dehydrogenase kinase (PDK), has been shown to exert a potent tumoricidal action against a variety of tumor cells. The main mode of its antineoplastic action implicates a shift of glycolysis to oxidative metabolism of glucose, leading to generation of cytotoxic reactive oxygen intermediates. However, the effect of DCA on tumor microenvironment, which in turn regulates tumor cell survival; remains speculative to a large extent. It is also unclear if DCA can exert any modulatory effect on the process of hematopoiesis, which is in a compromised state in tumor-bearing hosts undergoing chemotherapy. In view of these lacunas, the present study was undertaken to investigate the so far unexplored aspects with respect to the molecular mechanisms of DCA-dependent tumor growth retardation and chemosensitization. BALB/c mice were transplanted with Dalton's lymphoma (DL) cells, a T cell lymphoma of spontaneous origin, followed by administration of DCA with or without cisplatin. DCA-dependent tumor regression and chemosensitization to cisplatin was found to be associated with altered repertoire of key cell survival regulatory molecules, modulated glucose metabolism, accompanying reconstituted tumor microenvironment with respect to pH homeostasis, cytokine balance and alternatively activated TAM. Moreover, DCA administration also led to an alteration in the MDR phenotype of tumor cells and myelopoietic differentiation of macrophages. The findings of this study shed a new light with respect to some of the novel mechanisms underlying the antitumor action of DCA and thus may have immense clinical applications. - Highlights: • DCA modulates tumor progression and chemoresistance. • DCA alters molecules regulating cell survival, glucose metabolism and MDR. • DCA reconstitutes biophysical and cellular composition of tumor microenvironment.

  10. Androgen receptor and its splice variant, AR-V7, differentially regulate FOXA1 sensitive genes in LNCaP prostate cancer cells.

    Science.gov (United States)

    Krause, William C; Shafi, Ayesha A; Nakka, Manjula; Weigel, Nancy L

    2014-09-01

    Prostate cancer (PCa) is an androgen-dependent disease, and tumors that are resistant to androgen ablation therapy often remain androgen receptor (AR) dependent. Among the contributors to castration-resistant PCa are AR splice variants that lack the ligand-binding domain (LBD). Instead, they have small amounts of unique sequence derived from cryptic exons or from out of frame translation. The AR-V7 (or AR3) variant is constitutively active and is expressed under conditions consistent with CRPC. AR-V7 is reported to regulate a transcriptional program that is similar but not identical to that of AR. However, it is unknown whether these differences are due to the unique sequence in AR-V7, or simply to loss of the LBD. To examine transcriptional regulation by AR-V7, we have used lentiviruses encoding AR-V7 (amino acids 1-627 of AR with the 16 amino acids unique to the variant) to prepare a derivative of the androgen-dependent LNCaP cells with inducible expression of AR-V7. An additional cell line was generated with regulated expression of AR-NTD (amino acids 1-660 of AR); this mutant lacks the LBD but does not have the AR-V7 specific sequence. We find that AR and AR-V7 have distinct activities on target genes that are co-regulated by FOXA1. Transcripts regulated by AR-V7 were similarly regulated by AR-NTD, indicating that loss of the LBD is sufficient for the observed differences. Differential regulation of target genes correlates with preferential recruitment of AR or AR-V7 to specific cis-regulatory DNA sequences providing an explanation for some of the observed differences in target gene regulation. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. MAPK/JNK1 activation protects cells against cadmium-induced autophagic cell death via differential regulation of catalase and heme oxygenase-1 in oral cancer cells.

    Science.gov (United States)

    So, Keum-Young; Kim, Sang-Hun; Jung, Ki-Tae; Lee, Hyun-Young; Oh, Seon-Hee

    2017-10-01

    Antioxidant enzymes are related to oral diseases. We investigated the roles of heme oxygenase-1 (HO-1) and catalase in cadmium (Cd)-induced oxidative stress and the underlying molecular mechanism in oral cancer cells. Exposing YD8 cells to Cd reduced the expression levels of catalase and superoxide dismutase 1/2 and induced the expression of HO-1 as well as autophagy and apoptosis, which were reversed by N-acetyl-l-cysteine (NAC). Cd-exposed YD10B cells exhibited milder effects than YD8 cells, indicating that Cd sensitivity is associated with antioxidant enzymes and autophagy. Autophagy inhibition via pharmacologic and genetic modulations enhanced Cd-induced HO-1 expression, caspase-3 cleavage, and the production of reactive oxygen species (ROS). Ho-1 knockdown increased autophagy and apoptosis. Hemin treatment partially suppressed Cd-induced ROS production and apoptosis, but enhanced autophagy and CHOP expression, indicating that autophagy induction is associated with cellular stress. Catalase inhibition by pharmacological and genetic modulations increased Cd-induced ROS production, autophagy, and apoptosis, but suppressed HO-1, indicating that catalase is required for HO-1 induction. p38 inhibition upregulated Cd-induced phospho-JNK and catalase, but suppressed HO-1, autophagy, apoptosis. JNK suppression exhibited contrary results, enhancing the expression of phospho-p38. Co-suppression of p38 and JNK1 failed to upregulate catalase and procaspase-3, which were upregulated by JNK1 overexpression. Overall, the balance between the responses of p38 and JNK activation to Cd appears to have an important role in maintaining cellular homeostasis via the regulation of antioxidant enzymes and autophagy induction. In addition, the upregulation of catalase by JNK1 activation can play a critical role in cell protection against Cd-induced oxidative stress. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Adenosine Receptors Differentially Regulate the Expression of Regulators of G-Protein Signalling (RGS 2, 3 and 4 in Astrocyte-Like Cells.

    Directory of Open Access Journals (Sweden)

    Till Nicolas Eusemann

    Full Text Available The "regulators of g-protein signalling" (RGS comprise a large family of proteins that limit by virtue of their GTPase accelerating protein domain the signal transduction of G-protein coupled receptors. RGS proteins have been implicated in various neuropsychiatric diseases such as schizophrenia, drug abuse, depression and anxiety and aggressive behaviour. Since conditions associated with a large increase of adenosine in the brain such as seizures or ischemia were reported to modify the expression of some RGS proteins we hypothesized that adenosine might regulate RGS expression in neural cells. We measured the expression of RGS-2,-3, and -4 in both transformed glia cells (human U373 MG astrocytoma cells and in primary rat astrocyte cultures stimulated with adenosine agonists. Expression of RGS-2 mRNA as well as RGS2 protein was increased up to 30-fold by adenosine agonists in astrocytes. The order of potency of agonists and the blockade by the adenosine A2B-antagonist MRS1706 indicated that this effect was largely mediated by adenosine A2B receptors. However, a smaller effect was observed due to activation of adenosine A2A receptors. In astrocytoma cells adenosine agonists elicited an increase in RGS-2 expression solely mediated by A2B receptors. Expression of RGS-3 was inhibited by adenosine agonists in both astrocytoma cells and astrocytes. However while this effect was mediated by A2B receptors in astrocytoma cells it was mediated by A2A receptors in astrocytes as assessed by the order of potency of agonists and selective blockade by the specific antagonists MRS1706 and ZM241385 respectively. RGS-4 expression was inhibited in astrocytoma cells but enhanced in astrocytes by adenosine agonists.

  13. Bile acids deoxycholic acid and ursodeoxycholic acid differentially regulate human β-defensin-1 and -2 secretion by colonic epithelial cells.

    Science.gov (United States)

    Lajczak, Natalia K; Saint-Criq, Vinciane; O'Dwyer, Aoife M; Perino, Alessia; Adorini, Luciano; Schoonjans, Kristina; Keely, Stephen J

    2017-09-01

    Bile acids and epithelial-derived human β-defensins (HβDs) are known to be important factors in the regulation of colonic mucosal barrier function and inflammation. We hypothesized that bile acids regulate colonic HβD expression and aimed to test this by investigating the effects of deoxycholic acid (DCA) and ursodeoxycholic acid on the expression and release of HβD1 and HβD2 from colonic epithelial cells and mucosal tissues. DCA (10-150 µM) stimulated the release of both HβD1 and HβD2 from epithelial cell monolayers and human colonic mucosal tissue in vitro In contrast, ursodeoxycholic acid (50-200 µM) inhibited both basal and DCA-induced defensin release. Effects of DCA were mimicked by the Takeda GPCR 5 agonist, INT-777 (50 μM), but not by the farnesoid X receptor agonist, GW4064 (10 μM). INT-777 also stimulated colonic HβD1 and HβD2 release from wild-type, but not Takeda GPCR 5 -/- , mice. DCA stimulated phosphorylation of the p65 subunit of NF-κB, an effect that was attenuated by ursodeoxycholic acid, whereas an NF-κB inhibitor, BMS-345541 (25 μM), inhibited DCA-induced HβD2, but not HβD1, release. We conclude that bile acids can differentially regulate colonic epithelial HβD expression and secretion and discuss the implications of our findings for intestinal health and disease.-Lajczak, N. K., Saint-Criq, V., O'Dwyer, A. M., Perino, A., Adorini, L., Schoonjans, K., Keely, S. J. Bile acids deoxycholic acid and ursodeoxycholic acid differentially regulate human β-defensin-1 and -2 secretion by colonic epithelial cells. © FASEB.

  14. Cigarette Smoke Induction of Interleukin-27/WSX-1 Regulates the Differentiation of Th1 and Th17 Cells in a Smoking Mouse Model of Emphysema.

    Science.gov (United States)

    Qiu, Shi-Lin; Duan, Min-Chao; Liang, Yi; Tang, Hai-Juan; Liu, Guang-Nan; Zhang, Liang-Ming; Yang, Chao-Mian

    2016-01-01

    IFN-γ-producing CD4 + T (Th1) cells and IL-17-producing CD4 + T (Th17) cells play a critical role in the pathogenesis of chronic obstructive pulmonary disease (COPD). However, the immune regulation between Th1 and Th17 cells remains unclear. Previous studies have demonstrated that interleukin-27 (IL-27)/WSX-1 exerted pro- or anti-inflammatory effects in many acute inflammatory diseases by modulating T cell-mediated immune response, but little was known about its role in chronic inflammatory disease, especially in smoking-related lung diseases. Considering IL-27 is an important regulator in T lymphocytes immune responses and was found markedly increased in patients with COPD, we hypothesized that IL-27/WSX-1 may exert immuno-regulatory effects on the differentiation of Th1 and Th17 cells in smoking-related COPD. In this study, we aimed to evaluate the expression of IL-27 in patients with COPD and explore the role of IL-27/WSX-1 on Th1 and Th17 cells differentiation in a smoking mouse model of emphysema. We found that elevated expression of IL-27 was associated with increased proportion of Th1 cells and Th17 cells in patients with COPD and demonstrated parallel findings in cigarette smoke-exposed mice. In addition, cigarette smoke exposure upregulated the expression of IL-27R (WSX-1) by naive CD4 + T cells in mice. In vitro , IL-27 significantly augmented the secretion of IFN-γ by naive CD4 + T cells via a T-bet, p-STAT1, and p-STAT3-dependent manner, but inhibited the production of IL-17 by a ROR-γt and p-STAT1-dependent way. Furthermore, anti-IL27 treatment dramatically decreased the expression of IFN-γ-producing CD4 + T cells in cigarette smoke-exposed mice. These findings proposed that IL-27 has functions for promoting the expression of Th1 cells but inhibiting the expression of Th17 cells in vitro and IL-27 neutralization-attenuated Th1-mediated inflammation in vivo , suggesting targeting IL-27/WSX-1 may provide a new therapeutic approach for smoking

  15. Differential Regulation of Mas-Related G Protein-Coupled Receptor X2-Mediated Mast Cell Degranulation by Antimicrobial Host Defense Peptides and Porphyromonas gingivalis Lipopolysaccharide.

    Science.gov (United States)

    Gupta, Kshitij; Idahosa, Chizobam; Roy, Saptarshi; Lee, Donguk; Subramanian, Hariharan; Dhingra, Anuradha; Boesze-Battaglia, Kathleen; Korostoff, Jonathan; Ali, Hydar

    2017-10-01

    Porphyromonas gingivalis is a keystone pathogen that contributes to periodontal pathogenesis by disrupting host-microbe homeostasis and promoting dysbiosis. The virulence of P. gingivalis likely reflects an alteration in the lipid A composition of its lipopolysaccharide (LPS) from the penta-acylated ( Pg LPS 1690 ) to the tetra-acylated ( Pg LPS 1435/1449 ) form. Mast cells play an important role in periodontitis, but the mechanisms of their activation and regulation remain unknown. The expression of epithelium- and neutrophil-derived host defense peptides (HDPs) (LL-37 and human β-defensin-3), which activate mast cells via Mas-related G protein-coupled receptor X2 (MRGPRX2), is increased in periodontitis. We found that MRGPRX2-expressing mast cells are present in normal gingiva and that their numbers are elevated in patients with chronic periodontitis. Furthermore, HDPs stimulated degranulation in a human mast cell line (LAD2) and in RBL-2H3 cells stably expressing MRGPRX2 (RBL-MRGPRX2). Pg LPS 1690 caused substantial inhibition of HDP-induced mast cell degranulation, but Pg LPS 1435/1449 had no effect. A fluorescently labeled HDP (FAM-LL-37) bound to RBL-MRGPRX2 cells, and Pg LPS 1690 inhibited this binding, but Pg LPS 1435/1449 had no effect. These findings suggest that low-level inflammation induced by HDP/MRGPRX2-mediated mast cell degranulation contributes to gingival homeostasis but that sustained inflammation due to elevated levels of both HDPs and MRGPRX2-expressing mast cells promotes periodontal disease. Furthermore, differential regulation of HDP-induced mast cell degranulation by Pg LPS 1690 and Pg LPS 1435/1449 may contribute to the modulation of disease progression. Copyright © 2017 American Society for Microbiology.

  16. Bone morphogenetic protein signaling and olig1/2 interact to regulate the differentiation and maturation of adult oligodendrocyte precursor cells.

    Science.gov (United States)

    Cheng, Xiaoxin; Wang, Yaping; He, Qian; Qiu, Mengsheng; Whittemore, Scott R; Cao, Qilin

    2007-12-01

    Promotion of remyelination is an important therapeutic strategy for the treatment of the demyelinating neurological disorders. Adult oligodendrocyte precursor cells (OPCs), which normally reside quiescently in the adult central nervous system (CNS), become activated and proliferative after demyelinating lesions. However, the extent of endogenous remyelination is limited because of the failure of adult OPCs to mature into myelinating oligodendrocytes (OLs) in the demyelinated CNS. Understanding the molecular mechanisms that regulate the differentiation of adult OPCs could lead to new therapeutic strategies to treat these disorders. In this study, we established a stable culture of adult spinal cord OPCs and developed a reliable in vitro protocol to induce their sequential differentiation. Adult OPCs expressed bone morphogenetic protein (BMP) type Ia, Ib, and II receptor subunits, which are required for BMP signal transduction. BMP2 and 4 promoted dose-dependent astrocyte differentiation of adult OPCs with concurrent suppression of OL differentiation. Treatment of OPCs with BMP2 and 4 increased ID4 expression and decreased the expression of olig1 and olig2. Overexpression of olig1 or olig2 blocked the astrocyte differentiation of adult OPCs induced by BMP2 and 4. Furthermore, overexpression of both olig1 and olig2, but not olig1 or olig2 alone, rescued OL differentiation from inhibition by BMP2 and 4. Our results demonstrated that downregulation of olig1 and olig2 is an important mechanism by which BMP2 and 4 inhibit OL differentiation of adult OPCs. These data suggest that blocking BMP signaling combined with olig1/2 overexpression could be a useful therapeutic strategy to enhance endogenous remyelination and facilitate functional recovery in CNS demyelinated disorders. Disclosure of potential conflicts of interest is found at the end of this article.

  17. Cancer stem cells and differentiation therapy.

    Science.gov (United States)

    Jin, Xiong; Jin, Xun; Kim, Hyunggee

    2017-10-01

    Cancer stem cells can generate tumors from only a small number of cells, whereas differentiated cancer cells cannot. The prominent feature of cancer stem cells is its ability to self-renew and differentiate into multiple types of cancer cells. Cancer stem cells have several distinct tumorigenic abilities, including stem cell signal transduction, tumorigenicity, metastasis, and resistance to anticancer drugs, which are regulated by genetic or epigenetic changes. Like normal adult stem cells involved in various developmental processes and tissue homeostasis, cancer stem cells maintain their self-renewal capacity by activating multiple stem cell signaling pathways and inhibiting differentiation signaling pathways during cancer initiation and progression. Recently, many studies have focused on targeting cancer stem cells to eradicate malignancies by regulating stem cell signaling pathways, and products of some of these strategies are in preclinical and clinical trials. In this review, we describe the crucial features of cancer stem cells related to tumor relapse and drug resistance, as well as the new therapeutic strategy to target cancer stem cells named "differentiation therapy."

  18. PLD2 has both enzymatic and cell proliferation-inducing capabilities, that are differentially regulated by phosphorylation and dephosphorylation

    International Nuclear Information System (INIS)

    Henkels, Karen M.; Short, Stephen; Peng, Hong-Juan; Fulvio, Mauricio Di; Gomez-Cambronero, Julian

    2009-01-01

    Phospholipase D2 (PLD2) overexpression in mammalian cells results in cell transformation. We have hypothesized that this is due to an increase of de novo DNA synthesis. We show here that overexpression of PLD2-WT leads to an increased DNA synthesis, as measured by the expression levels of the proliferation markers PCNA, p27 KIP1 and phospho-histone-3. The enhancing effect was even higher with phosphorylation-deficient PLD2-Y179F and PLD2-Y511F mutants. The mechanism for this did not involve the enzymatic activity of the lipase, but, rather, the presence of the protein tyrosine phosphatase CD45, as silencing with siRNA for CD45 abrogated the effect. The two Y→F mutants had in common a YxN consensus site that, in the phosphorylated counterparts, could be recognized by SH2-bearing proteins, such as Grb2. Even though Y179F and Y511F cannot bind Grb2, they could still find other protein partners, one of which, we have reasoned, could be CD45 itself. Affinity purified PLD2 is indeed activated by Grb2 and deactivated by CD45 in vitro. We concluded that phosphorylated PLD2, aided by Grb2, mediates lipase activity, whereas dephosphorylated PLD2 mediates an induction of cell proliferation, and the specific residues involved in this newly discovered regulation of PLD2 are Y 179 and Y 511 .

  19. Transcriptional regulation by histone modifications: towards a theory of chromatin re-organization during stem cell differentiation

    International Nuclear Information System (INIS)

    Binder, Hans; Steiner, Lydia; Przybilla, Jens; Rohlf, Thimo; Prohaska, Sonja; Galle, Jörg

    2013-01-01

    Chromatin-related mechanisms, as e.g. histone modifications, are known to be involved in regulatory switches within the transcriptome. Only recently, mathematical models of these mechanisms have been established. So far they have not been applied to genome-wide data. We here introduce a mathematical model of transcriptional regulation by histone modifications and apply it to data of trimethylation of histone 3 at lysine 4 (H3K4me3) and 27 (H3K27me3) in mouse pluripotent and lineage-committed cells. The model describes binding of protein complexes to chromatin which are capable of reading and writing histone marks. Molecular interactions of the complexes with DNA and modified histones create a regulatory switch of transcriptional activity. The regulatory states of the switch depend on the activity of histone (de-) methylases, the strength of complex-DNA-binding and the number of nucleosomes capable of cooperatively contributing to complex-binding. Our model explains experimentally measured length distributions of modified chromatin regions. It suggests (i) that high CpG-density facilitates recruitment of the modifying complexes in embryonic stem cells and (ii) that re-organization of extended chromatin regions during lineage specification into neuronal progenitor cells requires targeted de-modification. Our approach represents a basic step towards multi-scale models of transcriptional control during development and lineage specification. (paper)

  20. The challenge of legitimizing spatially differentiated regulation

    DEFF Research Database (Denmark)

    Thorsøe, Martin Hvarregaard; Graversgaard, Morten; Noe, Egon

    2017-01-01

    Differentiating regulation is a promising approach to agri-environmental regulation that may potentially reduce the environmental impact of agriculture at the lowest possible costs for the farmers and society, but also possesses a number of challenges. In this article, we explore the challenges...... to the legitimacy of agri-environmental regulation that occurs when the regulatory regime changes from general regulation to differentiated regulation. The analysis is based on a case study of the implementation of the Buffer zone act in Denmark – a regulation that prevents agricultural production in a 10 (later 9......) meter fringe around selected waterbodies. We distinguish between two different ways of legitimizing: Producing knowledge and participation. We conclude that to harvest some of the obvious benefits of differentiated regulation a number of challenges must be resolved, 1) ensuring legitimacy...

  1. Chromatin in embryonic stem cell neuronal differentiation.

    Science.gov (United States)

    Meshorer, E

    2007-03-01

    Chromatin, the basic regulatory unit of the eukaryotic genetic material, is controlled by epigenetic mechanisms including histone modifications, histone variants, DNA methylation and chromatin remodeling. Cellular differentiation involves large changes in gene expression concomitant with alterations in genome organization and chromatin structure. Such changes are particularly evident in self-renewing pluripotent embryonic stem cells, which begin, in terms of cell fate, as a tabula rasa, and through the process of differentiation, acquire distinct identities. Here I describe the changes in chromatin that accompany neuronal differentiation, particularly of embryonic stem cells, and discuss how chromatin serves as the master regulator of cellular destiny.

  2. Triglyceride-rich lipoprotein modulates endothelial vascular cell adhesion molecule (VCAM-1 expression via differential regulation of endoplasmic reticulum stress.

    Directory of Open Access Journals (Sweden)

    Ying I Wang

    Full Text Available Circulating triglyceride-rich lipoproteins (TGRL from hypertriglyceridemic subjects exacerbate endothelial inflammation and promote monocyte infiltration into the arterial wall. We have recently reported that TGRL isolated from human blood after a high-fat meal can elicit a pro- or anti-atherogenic state in human aortic endothelial cells (HAEC, defined as up- or down-regulation of VCAM-1 expression in response to tumor necrosis factor alpha (TNFα stimulation, respectively. A direct correlation was found between subjects categorized at higher risk for cardiovascular disease based upon serum triglycerides and postprandial production of TGRL particles that increased VCAM-1-dependent monocyte adhesion to inflamed endothelium. To establish how TGRL metabolism is linked to VCAM-1 regulation, we examined endoplasmic reticulum (ER stress and the unfolded protein response (UPR pathways. Regardless of its atherogenicity, the rate and extent of TGRL internalization and lipid droplet formation by HAEC were uniform. However, pro-atherogenic TGRL exacerbated ER membrane expansion and stress following TNFα stimulation, whereas anti-atherogenic TGRL ameliorated such effects. Inhibition of ER stress with a chemical chaperone 4-phenylbutyric acid decreased TNFα-induced VCAM-1 expression and abrogated TGRL's atherogenic effect. Activation of ER stress sensors PKR-like ER-regulated kinase (PERK and inositol requiring protein 1α (IRE1α, and downstream effectors including eukaryotic initiation factor-2α (eIF2α, spliced X-box-binding protein 1 (sXBP1 and C/EBP homologous protein (CHOP, directly correlated with the atherogenic activity of an individual's TGRL. Modulation of ER stress sensors also correlated with changes in expression of interferon regulatory factor 1 (IRF-1, a transcription factor of Vcam-1 responsible for regulation of its expression. Moreover, knockdown studies using siRNA defined a causal relationship between the PERK/eIF2α/CHOP pathway and

  3. Delta-like 1/Fetal Antigen-1 (Dlk1/FA1) Is a Novel Regulator of Chondrogenic Cell Differentiation via Inhibition of the Akt Kinase-dependent Pathway*

    Science.gov (United States)

    Chen, Li; Qanie, Diyako; Jafari, Abbas; Taipaleenmaki, Hanna; Jensen, Charlotte H.; Säämänen, Anna-Marja; Sanz, Maria Luisa Nueda; Laborda, Jorge; Abdallah, Basem M.; Kassem, Moustapha

    2011-01-01

    Delta-like 1 (Dlk1, also known as fetal antigen-1, FA1) is a member of Notch/Delta family that inhibits adipocyte and osteoblast differentiation; however, its role in chondrogenesis is still not clear. Thus, we overexpressed Dlk1/FA1 in mouse embryonic ATDC5 cells and tested its effects on chondrogenic differentiation. Dlk1/FA1 inhibited insulin-induced chondrogenic differentiation as evidenced by reduction of cartilage nodule formation and gene expression of aggrecan, collagen Type II and X. Similar effects were obtained either by using Dlk1/FA1-conditioned medium or by addition of a purified, secreted, form of Dlk1 (FA1) directly to the induction medium. The inhibitory effects of Dlk1/FA1 were dose-dependent and occurred irrespective of the chondrogenic differentiation stage: proliferation, differentiation, maturation, or hypertrophic conversion. Overexpression or addition of the Dlk1/FA1 protein to the medium strongly inhibited the activation of Akt, but not the ERK1/2, or p38 MAPK pathways, and the inhibition of Akt by Dlk1/FA1 was mediated through PI3K activation. Interestingly, inhibition of fibronectin expression by siRNA rescued the Dlk1/FA1-mediated inhibition of Akt, suggesting interaction of Dlk1/FA1 and fibronectin in chondrogenic cells. Our results identify Dlk1/FA1 as a novel regulator of chondrogenesis and suggest Dlk1/FA1 acts as an inhibitor of the PI3K/Akt pathways that leads to its inhibitory effects on chondrogenesis. PMID:21724852

  4. EphA4 Regulates the Balance between Self-Renewal and Differentiation of Radial Glial Cells and Intermediate Neuronal Precursors in Cooperation with FGF Signaling.

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    Qingfa Chen

    Full Text Available In mouse cerebral corticogenesis, neurons are generated from radial glial cells (RGCs or from their immediate progeny, intermediate neuronal precursors (INPs. The balance between self-renewal of these neuronal precursors and specification of cell fate is critical for proper cortical development, but the signaling mechanisms that regulate this progression are poorly understood. EphA4, a member of the receptor tyrosine kinase superfamily, is expressed in RGCs during embryogenesis. To illuminate the function of EphA4 in RGC cell fate determination during early corticogenesis, we deleted Epha4 in cortical cells at E11.5 or E13.5. Loss of EphA4 at both stages led to precocious in vivo RGC differentiation toward neurogenesis. Cortical cells isolated at E14.5 and E15.5 from both deletion mutants showed reduced capacity for neurosphere formation with greater differentiation toward neurons. They also exhibited lower phosphorylation of ERK and FRS2α in the presence of FGF. The size of the cerebral cortex at P0 was smaller than that of controls when Epha4 was deleted at E11.5 but not when it was deleted at E13.5, although the cortical layers were formed normally in both mutants. The number of PAX6-positive RGCs decreased at later developmental stages only in the E11.5 Epha4 deletion mutant. These results suggest that EphA4, in cooperation with an FGF signal, contributes to the maintenance of RGC self-renewal and repression of RGC differentiation through the neuronal lineage. This function of EphA4 is especially critical and uncompensated in early stages of corticogenesis, and thus deletion at E11.5 reduces the size of the neonatal cortex.

  5. A Modified Chinese Herbal Decoction (Kai-Xin-San Promotes NGF-Induced Neuronal Differentiation in PC12 Cells via Up-Regulating Trk A Signaling

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    Lu Yan

    2017-12-01

    Full Text Available Kai-Xin-San (KXS, a Chinese herbal decoction, has been applied to medical care of depression for thousands of years. It is composed of two functional paired-herbs: Ginseng Radix et Rhizoma (GR-Polygalae Radix (PR and Acori Tatarinowii Rhizoma (ATR-Poria (PO. The compatibility of the paired-herbs has been frequently changed to meet the criteria of syndrome differentiation and treatment variation. Currently, a modified KXS (namely KXS2012 was prepared by optimizing the combinations of GR-PR and ATR-PO: the new herbal formula was shown to be very effective in animal studies. However, the cellular mechanism of KXS2012 against depression has not been fully investigated. Here, the study on KXS2012-induced neuronal differentiation in cultured PC12 cells was analyzed. In PC12 cultures, single application of KXS2012 showed no effect on the neuronal differentiation, but which showed robust effects in potentiating nerve growth factor (NGF-induced neurite outgrowth and neurofilament expression. The potentiating effect of KXS2012 was mediated through NGF receptor, tropomyosin receptor kinase (Trk A: because the receptor expression and activity was markedly up-regulated in the presence of KXS2012, and the potentiating effect was blocked by k252a, an inhibitor of Trk A. Our current results in cell cultures fully support the therapeutic efficacy of KXS2012 against depression.

  6. Song Bu Li Decoction, a Traditional Uyghur Medicine, Protects Cell Death by Regulation of Oxidative Stress and Differentiation in Cultured PC12 Cells

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    Maitinuer Maiwulanjiang

    2013-01-01

    Full Text Available Song Bu Li decoction (SBL is a traditional Uyghur medicinal herbal preparation, containing Nardostachyos Radix et Rhizoma. Recently, SBL is being used to treat neurological disorders (insomnia and neurasthenia and heart disorders (arrhythmia and palpitation. Although this herbal extract has been used for many years, there is no scientific basis about its effectiveness. Here, we aimed to evaluate the protective and differentiating activities of SBL in cultured PC12 cells. The pretreatment of SBL protected the cell against tBHP-induced cell death in a dose-dependent manner. In parallel, SBL suppressed intracellular reactive oxygen species (ROS formation. The transcriptional activity of antioxidant response element (ARE, as well as the key antioxidative stress proteins, was induced in dose-dependent manner by SBL in the cultures. In cultured PC12 cells, the expression of neurofilament, a protein marker for neuronal differentiation, was markedly induced by applied herbal extract. Moreover, the nerve growth factor- (NGF- induced neurite outgrowth in cultured PC12 cells was significantly potentiated by the cotreatment of SBL. In accord, the expression of neurofilament was increased in the treatment of SBL. These results therefore suggested a possible role of SBL by its effect on neuron differentiation and protection against oxidative stress.

  7. Cocaine- and amphetamine-regulated transcript promotes the differentiation of mouse bone marrow-derived mesenchymal stem cells into neural cells

    OpenAIRE

    Jin Jiali; Chen Zhibin; Zhang Meijuan; Huang Danqing; Liu Zhuo; Huang Siyuan; Zhang Zhuo; Wang Zhongyuan; Chen Lei; Chen Ling; Xu Yun

    2011-01-01

    Abstract Background Neural tissue has limited potential to self-renew after neurological damage. Cell therapy using BM-MSCs (bone marrow mesenchymal stromal cells) seems like a promising approach for the treatment of neurological diseases. However, the neural differentiation of stem cells influenced by massive factors and interactions is not well studied at present. Results In this work, we isolated and identified MSCs from mouse bone marrow. Co-cultured with CART (0.4 nM) for six days, BM-MS...

  8. IGF-1/IGF-1R/hsa-let-7c axis regulates the committed differentiation of stem cells from apical papilla

    Science.gov (United States)

    Ma, Shu; Liu, Genxia; Jin, Lin; Pang, Xiyao; Wang, Yanqiu; Wang, Zilu; Yu, Yan; Yu, Jinhua

    2016-01-01

    Insulin-like growth factor-1 (IGF-1) and its receptor IGF-1R play a paramount role in tooth/bone formation while hsa-let-7c actively participates in the osteogenic differentiation of mesenchymal stem cells. However, the interaction between IGF-1/IGF-1R and hsa-let-7c on the committed differentiation of stem cells from apical papilla (SCAPs) remains unclear. In this study, human SCAPs were isolated and treated with IGF-1 and hsa-let-7c over/low-expression viruses. The odonto/osteogenic differentiation of these stem cells and the involvement of mitogen-activated protein kinase (MAPK) pathway were subsequently investigated. Alizarin red staining showed that hsa-let-7c low-expression can significantly promote the mineralization of IGF-1 treated SCAPs, while hsa-let-7c over-expression can decrease the calcium deposition of IGF-1 treated SCAPs. Western blot assay and real-time reverse transcription polymerase chain reaction further demonstrated that the expression of odonto/osteogenic markers (ALP, RUNX2/RUNX2, OSX/OSX, OCN/OCN, COL-I/COL-I, DSPP/DSP, and DMP-1/DMP-1) in IGF-1 treated SCAPs were significantly upregulated in Let-7c-low group. On the contrary, hsa-let-7c over-expression could downregulate the expression of these odonto/osteogenic markers. Moreover, western blot assay showed that the JNK and p38 MAPK signaling pathways were activated in Let-7c-low SCAPs but inhibited in Let-7c-over SCAPs. Together, the IGF-1/IGF-1R/hsa-let-7c axis can control the odonto/osteogenic differentiation of IGF-1-treated SCAPs via the regulation of JNK and p38 MAPK signaling pathways. PMID:27833148

  9. Role of Myoendothelial Gap Junctions in the Regulation of Human Coronary Artery Smooth Muscle Cell Differentiation by Laminar Shear Stress

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    Zongqi Zhang

    2016-07-01

    Full Text Available Background/Aims: Smooth muscle cells may dedifferentiate into the synthetic phenotype and promote atherosclerosis. Here, we explored the role of myoendothelial gap junctions in phenotypic switching of human coronary artery smooth muscle cells (HCASMCs co-cultured with human coronary artery endothelial cells (HCAECs exposed to shear stress. Methods: HCASMCs and HCAECs were seeded on opposite sides of Transwell inserts, and HCAECs were exposed to laminar shear stress of 12 dyn/cm2 or 5 dyn/cm2. The myoendothelial gap junctions were evaluated by using a multi-photon microscope. Results: In co-culture with HCAECs, HCASMCs exhibited a contractile phenotype, and maintained the expression of differentiation markers MHC and H1-calponin. HCASMCs and HCAECs formed functional intercellular junctions, as evidenced by colocalization of connexin(Cx40 and Cx43 on cellular projections inside the Transwell membrane and biocytin transfer from HCAECs to HCASMCs. Cx40 siRNA and 18-α-GA attenuated protein expression of MHC and H1-calponin in HCASMCs. Shear stress of 5 dyn/cm2 increased Cx43 and decreased Cx40 expression in HCAECs, and partly inhibited biocytin transfer from HCAECs to HCASMCs, which could be completely blocked by Cx43 siRNA or restored by Cx40 DNA transfected into HCAECs. The exposure of HCAECs to shear stress of 5 dyn/cm2 promoted HCASMC phenotypic switching, manifested by morphological changes, decrease in MHC and H1-calponin expression, and increase in platelet-derived growth factor (PDGF-BB release, which was partly rescued by Cx43 siRNA or Cx40 DNA or PDGF receptor signaling inhibitor. Conclusions: The exposure of HCAECs to shear stress of 5 dyn/cm2 caused the dysfunction of Cx40/Cx43 heterotypic myoendothelial gap junctions, which may be replaced by homotypic Cx43/Cx43 channels, and induced HCASMC transition to the synthetic phenotype associated with the activation of PDGF receptor signaling, which may contribute to shear stress

  10. Platyphylloside Isolated From Betula platyphylla Inhibit Adipocyte Differentiation and Induce Lipolysis Via Regulating Adipokines Including PPARγ in 3T3-L1 Cells

    Science.gov (United States)

    Lee, Mina; Sung, Sang Hyun

    2016-01-01

    Background: Obesity causes or aggravates many health problems, both independently and in association with several pathological disorders, including Type II diabetes, hypertension, atherosclerosis, and cancer. Therefore, we screened small compounds isolated from natural products for the development of anti-obesity drugs. Objective: The purpose of this study was to investigate the anti-adipogenic activities of platyphylloside, diarylheptanoid isolated from Betula platyphylla, which was selected based on the screening using 3T3-L1 cells. Materials and Methods: To evaluate the inhibition of adipocyte differentiation and lipolysis, lipid contents of BPP on were measured using Oil Red O staining in 3T3-L1 cells. The mRNA and protein expression levels of various adipokines were measured by Quantitative real-time PCR and Western blotting analysis, respectively. Results: Platyphylloside showed significant inhibitory activity on adipocyte differentiation in 3T3-L1 cells and suppressed adipocyte differentiation even in the presence of troglitazone, a PPARγ agonist. Platyphylloside might suppress adipocyte differentiation through PPARγ, C/EBPα, and SREBP1-induced adipogenesis, which is synergistically associated with downstream adipocyte-specific gene promoters such as aP2, FAS, SCD-1, LPL, and Adiponectin. In addition, platyphylloside affected lipolysis by down-regulating perilipin and HSL and up-regulating TNFα. Conclusion: Taken together, the results reveal that platyphylloside has anti-adipogenic activity and highlight its potential in the prevention and treatment of obesity. SUMMARY The extract of B. platyphylla bark and its isolate, BPP, had anti-adipogenic activity in 3T3-L1 cells via suppression of adipocyte differentiation from preadipocytes.Treatment with BPP significantly down-regulated the expression of PPARγ, C/EBP, C/EBPβ, C/EBPδ, SREBP1c, SCD-1, FAS, aP2 and LPL.BPP induced a lipolytic response in mature adipocytes via up-regulation krof TNFá and down-regulation

  11. Naringin promotes osteogenic differentiation of bone marrow stromal cells by up-regulating Foxc2 expression via the IHH signaling pathway.

    Science.gov (United States)

    Lin, Fei-Xiang; Du, Shi-Xin; Liu, De-Zhong; Hu, Qin-Xiao; Yu, Guo-Yong; Wu, Chu-Cheng; Zheng, Gui-Zhou; Xie, Da; Li, Xue-Dong; Chang, Bo

    2016-01-01

    Naringin is an active compound extracted from Rhizoma Drynariae, and studies have revealed that naringin can promote proliferation and osteogenic differentiation of bone marrow stromal cells (BMSCs). In this study, we explored whether naringin could promote osteogenic differentiation of BMSCs by upregulating Foxc2 expression via the Indian hedgehog (IHH) signaling pathway. BMSCs were cultured in basal medium, basal medium with naringin, osteogenic induction medium, osteogenic induction medium with naringin and osteogenic induction medium with naringin in the presence of the IHH inhibitor cyclopamine (CPE). We examined cell proliferation by using a WST-8 assay, and differentiation by Alizarin Red S staining (for mineralization) and alkaline phosphatase (ALP) activity. In addition, we detected core-binding factor α1 (Cbfα1), osteocalcin (OCN), bone sialoprotein (BSP), peroxisome proliferation-activated receptor gamma 2 (PPARγ2) and Foxc2 expression by using RT-PCR. We also determined Foxc2 and IHH protein levels by western blotting. Naringin increased the mineralization of BMSCs, as shown by Alizarin red S assays, and induced ALP activity. In addition, naringin significantly increased the mRNA levels of Foxc2, Cbfα1, OCN, and BSP, while decreasing PPARγ2 mRNA levels. Furthermore, the IHH inhibitor CPE inhibited the osteogenesis-potentiating effects of naringin. Naringin increased Foxc2 and stimulated the activation of IHH, as evidenced by increased expression of proteins that were inhibited by CPE. Our findings indicate that naringin promotes osteogenic differentiation of BMSCs by up-regulating Foxc2 expression via the IHH signaling pathway.

  12. Long-chain bases and their phosphorylated derivatives differentially regulate cryptogein-induced production of reactive oxygen species in tobacco (Nicotiana tabacum) BY-2 cells.

    Science.gov (United States)

    Coursol, Sylvie; Fromentin, Jérôme; Noirot, Elodie; Brière, Christian; Robert, Franck; Morel, Johanne; Liang, Yun-Kuan; Lherminier, Jeannine; Simon-Plas, Françoise

    2015-02-01

    The proteinaceous elicitor cryptogein triggers defence reactions in Nicotiana tabacum (tobacco) through a signalling cascade, including the early production of reactive oxygen species (ROS) by the plasma membrane (PM)-located tobacco respiratory burst oxidase homologue D (NtRbohD). Sphingolipid long-chain bases (LCBs) are emerging as potent positive regulators of plant defence-related mechanisms. This led us to question whether both LCBs and their phosphorylated derivatives (LCB-Ps) are involved in the early signalling process triggered by cryptogein in tobacco BY-2 cells. Here, we showed that cryptogein-induced ROS production was inhibited by LCB kinase (LCBK) inhibitors. Additionally, Arabidopsis thaliana sphingosine kinase 1 and exogenously supplied LCB-Ps increased cryptogein-induced ROS production, whereas exogenously supplied LCBs had a strong opposite effect, which was not driven by a reduction in cellular viability. Immunogold-electron microscopy assay also revealed that LCB-Ps are present in the PM, which fits well with the presence of a high LCBK activity associated with this fraction. Our data demonstrate that LCBs and LCB-Ps differentially regulate cryptogein-induced ROS production in tobacco BY-2 cells, and support a model in which a cooperative synergism between LCBK/LCB-Ps and NtRbohD/ROS in the cryptogein signalling pathway is likely at the PM in tobacco BY-2 cells. © 2014 INRA New Phytologist © 2014 New Phytologist Trust.

  13. Cell-penetrating superoxide dismutase attenuates oxidative stress-induced senescence by regulating the p53-p21Cip1 pathway and restores osteoblastic differentiation in human dental pulp stem cells

    Directory of Open Access Journals (Sweden)

    Park YJ

    2012-09-01

    Full Text Available Yoon Jung Choi,1,* Jue Yeon Lee,2,* Chong Pyoung Chung,2 Yoon Jeong Park,1,21Craniomaxillofacial Reconstructive Sciences, Dental Research Institute, School of Dentistry, Seoul National University, Seoul, Republic of Korea; 2Research Institute, Nano Intelligent Biomedical Engineering, Seoul, Republic of Korea*These authors contributed equally to this workBackground: Human dental pulp stem cells (DPSCs have potential applications in tissue regeneration because of their convenient cell harvesting procedures and multipotent capacity. However, the tissue regenerative potential of DPSCs is known to be negatively regulated by aging in long-term culture and under oxidative stress. With an aim of reducing cellular senescence and oxidative stress in DPSCs, an intracellular delivery system for superoxide dismutase 1 (SOD1 was developed. We conjugated SOD1 with a cell-penetrating peptide known as low-molecular weight protamine (LMWP, and investigated the effect of LMWP-SOD1 conjugates on hydrogen peroxide-induced cellular senescence and osteoblastic differentiation.Results: LMWP-SOD1 significantly attenuated enlarged and flattened cell morphology and increased senescence-associated β-galactosidase activity. Under the same conditions, LMWP-SOD1 abolished activation of the cell cycle regulator proteins, p53 and p21Cip1, induced by hydrogen peroxide. In addition, LMWP-SOD1 reversed the inhibition of osteoblastic differentiation and downregulation of osteogenic gene markers induced by hydrogen peroxide. However, LMWP-SOD1 could not reverse the decrease in odontogenesis caused by hydrogen peroxide.Conclusion: Overall, cell-penetrating LMWP-SOD1 conjugates are effective for attenuation of cellular senescence and reversal of osteoblastic differentiation of DPSCs caused by oxidative stress inhibition. This result suggests potential application in the field of antiaging and tissue engineering to overcome the limitations of senescent stem cells.Keywords: superoxide

  14. The Regulation of Lactogenic Differentiation in Mammary Epithelial Cells by Ras-Dependent and -Independent Signal Transduction

    Science.gov (United States)

    2006-01-06

    Lynch, 2002). In normal cells, programmed cell 19 death controls excessive proliferation. Most cancer cells, however, have devised methods for...also phosphorylates and inactivates caspase 9, a cell death -promoting protease. Phosphorylation of another Akt target, FKHR1, prevents its nuclear...Cancer Res 50:4204–4208. Gao J, Horseman N. 1999. Prolactin-independent modulation of the beta-casein response element by Erk2 Map kinase. Cell

  15. Forkhead Box C1 Regulates Human Primary Keratinocyte Terminal Differentiation.

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    Lianghua Bin

    Full Text Available The epidermis serves as a critical protective barrier between the internal and external environment of the human body. Its remarkable barrier function is established through the keratinocyte (KC terminal differentiation program. The transcription factors specifically regulating terminal differentiation remain largely unknown. Using a RNA-sequencing (RNA-seq profiling approach, we found that forkhead box c 1 (FOXC1 was significantly up-regulated in human normal primary KC during the course of differentiation. This observation was validated in human normal primary KC from several different donors and human skin biopsies. Silencing FOXC1 in human normal primary KC undergoing differentiation led to significant down-regulation of late terminal differentiation genes markers including epidermal differentiation complex genes, keratinization genes, sphingolipid/ceramide metabolic process genes and epidermal specific cell-cell adhesion genes. We further demonstrated that FOXC1 works down-stream of ZNF750 and KLF4, and upstream of GRHL3. Thus, this study defines FOXC1 as a regulator specific for KC terminal differentiation and establishes its potential position in the genetic regulatory network.

  16. Plasma Membrane Ca2+-Permeable Channels are Differentially Regulated by Ethylene and Hydrogen Peroxide to Generate Persistent Plumes of Elevated Cytosolic Ca2+ During Transfer Cell Trans-Differentiation.

    Science.gov (United States)

    Zhang, Hui-ming; van Helden, Dirk F; McCurdy, David W; Offler, Christina E; Patrick, John W

    2015-09-01

    The enhanced transport capability of transfer cells (TCs) arises from their ingrowth wall architecture comprised of a uniform wall on which wall ingrowths are deposited. The wall ingrowth papillae provide scaffolds to amplify plasma membranes that are enriched in nutrient transporters. Using Vicia faba cotyledons, whose adaxial epidermal cells spontaneously and rapidly (hours) undergo a synchronous TC trans-differentiation upon transfer to culture, has led to the discovery of a cascade of inductive signals orchestrating deposition of ingrowth wall papillae. Auxin-induced ethylene biosynthesis initiates the cascade. This in turn drives a burst in extracellular H2O2 production that triggers uniform wall deposition. Thereafter, a persistent and elevated cytosolic Ca(2+) concentration, resulting from Ca(2+) influx through plasma membrane Ca(2+)-permeable channels, generates a Ca(2+) signal that directs formation of wall ingrowth papillae to specific loci. We now report how these Ca(2+)-permeable channels are regulated using the proportionate responses in cytosolic Ca(2+) concentration as a proxy measure of their transport activity. Culturing cotyledons on various combinations of pharmacological agents allowed the regulatory influence of each upstream signal on Ca(2+) channel activity to be evaluated. The findings demonstrated that Ca(2+)-permeable channel activity was insensitive to auxin, but up-regulated by ethylene through two independent routes. In one route ethylene acts directly on Ca(2+)-permeable channel activity at the transcriptional and post-translational levels, through an ethylene receptor-dependent pathway. The other route is mediated by an ethylene-induced production of extracellular H2O2 which then acts translationally and post-translationally to up-regulate Ca(2+)-permeable channel activity. A model describing the differential regulation of Ca(2+)-permeable channel activity is presented. © The Author 2015. Published by Oxford University Press on

  17. Peroxisomes in Different Skeletal Cell Types during Intramembranous and Endochondral Ossification and Their Regulation during Osteoblast Differentiation by Distinct Peroxisome Proliferator-Activated Receptors.

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    Guofeng Qian

    Full Text Available Ossification defects leading to craniofacial dysmorphism or rhizomelia are typical phenotypes in patients and corresponding knockout mouse models with distinct peroxisomal disorders. Despite these obvious skeletal pathologies, to date no careful analysis exists on the distribution and function of peroxisomes in skeletal tissues and their alterations during ossification. Therefore, we analyzed the peroxisomal compartment in different cell types of mouse cartilage and bone as well as in primary cultures of calvarial osteoblasts. The peroxisome number and metabolism strongly increased in chondrocytes during endochondral ossification from the reserve to the hypertrophic zone, whereas in bone, metabolically active osteoblasts contained a higher numerical abundance of this organelle than osteocytes. The high abundance of peroxisomes in these skeletal cell types is reflected by high levels of Pex11β gene expression. During culture, calvarial pre-osteoblasts differentiated into secretory osteoblasts accompanied by peroxisome proliferation and increased levels of peroxisomal genes and proteins. Since many peroxisomal genes contain a PPAR-responsive element, we analyzed the gene expression of PPARɑ/ß/ɣ in calvarial osteoblasts and MC3T3-E1 cells, revealing higher levels for PPARß than for PPARɑ and PPARɣ. Treatment with different PPAR agonists and antagonists not only changed the peroxisomal compartment and associated gene expression, but also induced complex alterations of the gene expression patterns of the other PPAR family members. Studies in M3CT3-E1 cells showed that the PPARß agonist GW0742 activated the PPRE-mediated luciferase expression and up-regulated peroxisomal gene transcription (Pex11, Pex13, Pex14, Acox1 and Cat, whereas the PPARß antagonist GSK0660 led to repression of the PPRE and a decrease of the corresponding mRNA levels. In the same way, treatment of calvarial osteoblasts with GW0742 increased in peroxisome number and

  18. DNA microarray profiling of genes differentially regulated by the histone deacetylase inhibitors vorinostat and LBH589 in colon cancer cell lines

    Directory of Open Access Journals (Sweden)

    Lenz Heinz-Josef

    2009-11-01

    Full Text Available Abstract Background Despite the significant progress made in colon cancer chemotherapy, advanced disease remains largely incurable and novel efficacious chemotherapies are urgently needed. Histone deacetylase inhibitors (HDACi represent a novel class of agents which have demonstrated promising preclinical activity and are undergoing clinical evaluation in colon cancer. The goal of this study was to identify genes in colon cancer cells that are differentially regulated by two clinically advanced hydroxamic acid HDACi, vorinostat and LBH589 to provide rationale for novel drug combination partners and identify a core set of HDACi-regulated genes. Methods HCT116 and HT29 colon cancer cells were treated with LBH589 or vorinostat and growth inhibition, acetylation status and apoptosis were analyzed in response to treatment using MTS, Western blotting and flow cytometric analyses. In addition, gene expression was analyzed using the Illumina Human-6 V2 BeadChip array and Ingenuity® Pathway Analysis. Results Treatment with either vorinostat or LBH589 rapidly induced histone acetylation, cell cycle arrest and inhibited the growth of both HCT116 and HT29 cells. Bioinformatic analysis of the microarray profiling revealed significant similarity in the genes altered in expression following treatment with the two HDACi tested within each cell line. However, analysis of genes that were altered in expression in the HCT116 and HT29 cells revealed cell-line-specific responses to HDACi treatment. In addition a core cassette of 11 genes modulated by both vorinostat and LBH589 were identified in both colon cancer cell lines analyzed. Conclusion This study identified HDACi-induced alterations in critical genes involved in nucleotide metabolism, angiogenesis, mitosis and cell survival which may represent potential intervention points for novel therapeutic combinations in colon cancer. This information will assist in the identification of novel pathways and targets

  19. Ethylene regulates Apple (Malus x domestica) fruit softening through a dose x time-dependent mechanism and through differential sensitivities and dependencies of cell wall-modifying genes.

    Science.gov (United States)

    Ireland, Hilary S; Gunaseelan, Kularajathevan; Muddumage, Ratnasiri; Tacken, Emma J; Putterill, Jo; Johnston, Jason W; Schaffer, Robert J

    2014-05-01

    In fleshy fruit species that have a strong requirement for ethylene to ripen, ethylene is synthesized autocatalytically, producing increasing concentrations as the fruits ripen. Apple fruit with the ACC OXIDASE 1 (ACO1) gene suppressed cannot produce ethylene autocatalytically at ripening. Using these apple lines, an ethylene sensitivity dependency model was previously proposed, with traits such as softening showing a high dependency for ethylene as well as low sensitivity. In this study, it is shown that the molecular control of fruit softening is a complex process, with different cell wall-related genes being independently regulated and exhibiting differential sensitivities to and dependencies on ethylene at the transcriptional level. This regulation is controlled through a dose × time mechanism, which results in a temporal transcriptional response that would allow for progressive cell wall disassembly and thus softening. This research builds on the sensitivity dependency model and shows that ethylene-dependent traits can progress over time to the same degree with lower levels of ethylene. This suggests that a developmental clock measuring cumulative ethylene controls the fruit ripening process.

  20. CD11c(hi) Dendritic Cells Regulate Ly-6C(hi) Monocyte Differentiation to Preserve Immune-privileged CNS in Lethal Neuroinflammation.

    Science.gov (United States)

    Kim, Jin Hyoung; Choi, Jin Young; Kim, Seong Bum; Uyangaa, Erdenebelig; Patil, Ajit Mahadev; Han, Young Woo; Park, Sang-Youel; Lee, John Hwa; Kim, Koanhoi; Eo, Seong Kug

    2015-12-02

    Although the roles of dendritic cells (DCs) in adaptive defense have been defined well, the contribution of DCs to T cell-independent innate defense and subsequent neuroimmunopathology in immune-privileged CNS upon infection with neurotropic viruses has not been completely defined. Notably, DC roles in regulating innate CD11b(+)Ly-6C(hi) monocyte functions during neuroinflammation have not yet been addressed. Using selective ablation of CD11c(hi)PDCA-1(int/lo) DCs without alteration in CD11c(int)PDCA-1(hi) plasmacytoid DC number, we found that CD11c(hi) DCs are essential to control neuroinflammation caused by infection with neurotropic Japanese encephalitis virus, through early and increased infiltration of CD11b(+)Ly-6C(hi) monocytes and higher expression of CC chemokines. More interestingly, selective CD11c(hi) DC ablation provided altered differentiation and function of infiltrated CD11b(+)Ly-6C(hi) monocytes in the CNS through Flt3-L and GM-CSF, which was closely associated with severely enhanced neuroinflammation. Furthermore, CD11b(+)Ly-6C(hi) monocytes generated in CD11c(hi) DC-ablated environment had a deleterious rather than protective role during neuroinflammation, and were more quickly recruited into inflamed CNS, depending on CCR2, thereby exacerbating neuroinflammation via enhanced supply of virus from the periphery. Therefore, our data demonstrate that CD11c(hi) DCs provide a critical and unexpected role to preserve the immune-privileged CNS in lethal neuroinflammation via regulating the differentiation, function, and trafficking of CD11b(+)Ly-6C(hi) monocytes.

  1. Epigenetic Library Screen Identifies Abexinostat as Novel Regulator of Adipocytic and Osteoblastic Differentiation of Human Skeletal (Mesenchymal) Stem Cells

    DEFF Research Database (Denmark)

    Ali, D.; Hamam, R.; Alfayez, M.

    2016-01-01

    proliferation and differentiation that were targeted by abexinostat. Concordantly, ChIP-quantitative polymerase chain reaction revealed marked increase in H3K9Ac epigenetic mark on the promoter region of AdipoQ, FABP4, PPARγ, KLF15, CEBPA, SP7, and ALPL in abexinostat-treated hMSCs. Pharmacological inhibition...

  2. Divergent branches of mitochondrial signaling regulate specific genes and the viability of specialized cell types of differentiated yeast colonies

    Czech Academy of Sciences Publication Activity Database

    Podholová, K.; Plocek, V.; Rešetárová, Stanislava; Kučerová, H.; Hlaváček, Otakar; Váchová, Libuše; Palková, Z.

    2016-01-01

    Roč. 7, č. 13 (2016), s. 15299-15314 ISSN 1949-2553 R&D Projects: GA ČR(CZ) GA15-08225S; GA MŠk(CZ) ED1.1.00/02.0109; GA MŠk(CZ) EE2.3.30.0003 Institutional support: RVO:61388971 Keywords : mitochondrial retrograde signaling * development and differentiation * ageing and longevity Subject RIV: EE - Microbiology, Virology Impact factor: 5.168, year: 2016

  3. SPDEF is required for mouse pulmonary goblet cell differentiation and regulates a network of genes associated with mucus production

    NARCIS (Netherlands)

    Chen, G.; Korfhagen, T.R.; Xu, Y.; Kitzmiller, J.; Wert, S.E.; Maeda, Y.; Gregorieff, A.; Clevers, H.; Whitsett, J.A.

    2009-01-01

    Various acute and chronic inflammatory stimuli increase the number and activity of pulmonary mucus-producing goblet cells, and goblet cell hyperplasia and excess mucus production are central to the pathogenesis of chronic pulmonary diseases. However, little is known about the transcriptional

  4. Poly(acrylic acid-regulated Synthesis of Rod-Like Calcium Carbonate Nanoparticles for Inducing the Osteogenic Differentiation of MC3T3-E1 Cells

    Directory of Open Access Journals (Sweden)

    Wei Yang

    2016-05-01

    Full Text Available Calcium carbonate, especially with nanostructure, has been considered as a good candidate material for bone regeneration due to its excellent biodegradability and osteoconductivity. In this study, rod-like calcium carbonate nanoparticles (Rod-CC NPs with desired water dispersibility were achieved with the regulation of poly (acrylic acid. Characterization results revealed that the Rod-CC NPs had an average length of 240 nm, a width of 90 nm with an average aspect ratio of 2.60 and a negative ζ-potential of −22.25 ± 0.35 mV. The degradation study illustrated the nanoparticles degraded 23% at pH 7.4 and 45% at pH 5.6 in phosphate-buffered saline (PBS solution within three months. When cultured with MC3T3-E1 cells, the Rod-CC NPs exhibited a positive effect on the proliferation of osteoblast cells. Alkaline phosphatase (ALP activity assays together with the osteocalcin (OCN and bone sialoprotein (BSP expression observations demonstrated the nanoparticles could induce the differentiation of MC3T3-E1 cells. Our study developed well-dispersed rod-like calcium carbonate nanoparticles which have great potential to be used in bone regeneration.

  5. Subchondral mesenchymal stem cells from osteoarthritic knees display high osteogenic differentiation capacity through microRNA-29a regulation of HDAC4.

    Science.gov (United States)

    Lian, Wei-Shiung; Wu, Ren-Wen; Lee, Mel S; Chen, Yu-Shan; Sun, Yi-Chih; Wu, Shing-Long; Ke, Huei-Jing; Ko, Jih-Yang; Wang, Feng-Sheng

    2017-12-01

    Subchondral bone deterioration and osteophyte formation attributable to excessive mineralization are prominent features of end-stage knee osteoarthritis (OA). The cellular events underlying subchondral integrity diminishment remained elusive. This study was undertaken to characterize subchondral mesenchymal stem cells (SMSCs) isolated from patients with end-stage knee OA who required total knee arthroplasty. The SMSCs expressed surface antigens CD29, CD44, CD73, CD90, CD105, and CD166 and lacked CD31, CD45, and MHCII expression. The cell cultures exhibited higher proliferation and greater osteogenesis and chondrogenesis potencies, whereas their population-doubling time and adipogenic lineage commitment were lower than those of bone marrow MSCs (BMMSCs). They also displayed higher expressions of embryonic stem cell marker OCT3/4 and osteogenic factors Wnt3a, β-catenin, and microRNA-29a (miR-29a), concomitant with lower expressions of joint-deleterious factors HDAC4, TGF-β1, IL-1β, TNF-α, and MMP3, in comparison with those of BMMSCs. Knockdown of miR-29a lowered Wnt3a expression and osteogenic differentiation of the SMSCs through elevating HDAC4 translation, which directly regulated the 3'-untranslated region of HDAC4. Likewise, transgenic mice that overexpressed miR-29a in osteoblasts exhibited a high bone mass in the subchondral region. SMSCs in the transgenic mice showed a higher osteogenic differentiation and lower HDAC4 signaling than those in wild-type mice. Taken together, high osteogenesis potency existed in the SMSCs in the osteoarthritic knee. The miR-29a modulation of HDAC4 and Wnt3a signaling was attributable to the increase in osteogenesis. This study shed an emerging light on the characteristics of SMSCs and highlighted the contribution of SMSCs in the exacerbation of subchondral integrity in end-stage knee OA. Subchondral MSCs (SMSCs) from OA knee expressed embryonic stem cell marker Oct3/4. The SMSCs showed high proliferation and osteogenic and

  6. Time-resolved transcriptome and proteome landscape of human regulatory T cell (Treg) differentiation reveals novel regulators of FOXP3

    KAUST Repository

    Schmidt, Angelika; Marabita, Francesco; Kiani, Narsis A.; Gross, Catharina C.; Johansson, Henrik J.; É liá s, Szabolcs; Rautio, Sini; Eriksson, Matilda; Fernandes, Sunjay Jude; Silberberg, Gilad; Ullah, Ubaid; Bhatia, Urvashi; Lä hdesmä ki, Harri; Lehtiö , Janne; Gomez-Cabrero, David; Wiendl, Heinz; Lahesmaa, Riitta; Tegner, Jesper

    2018-01-01

    BackgroundRegulatory T cells (Tregs) expressing the transcription factor FOXP3 are crucial mediators of self-tolerance, preventing autoimmune diseases but possibly hampering tumor rejection. Clinical manipulation of Tregs is of great interest

  7. Dynamic regulation of genes involved in mitochondrial DNA replication and transcription during mouse brown fat cell differentiation and recruitment

    DEFF Research Database (Denmark)

    Murholm, Maria; Dixen, Karen; Qvortrup, Klaus

    2009-01-01

    BACKGROUND: Brown adipocytes are specialised in dissipating energy through adaptive thermogenesis, whereas white adipocytes are specialised in energy storage. These essentially opposite functions are possible for two reasons relating to mitochondria, namely expression of uncoupling protein 1 (UCP1...... and brown fat, brown adipose tissue fractions and in selected adipose tissues during cold exposure. We find a massive induction of the majority of such genes during brown adipocyte differentiation and recruitment, e.g. of the mitochondrial transcription factors A (Tfam) and B2 (Tfb2m), whereas only a subset...

  8. CsSCL1 is differentially regulated upon maturation in chestnut microshoots and is specifically expressed in rooting-competent cells.

    Science.gov (United States)

    Vielba, Jesús M; Díaz-Sala, Carmen; Ferro, Enrique; Rico, Saleta; Lamprecht, María; Abarca, Dolores; Ballester, Antonio; Sánchez, Conchi

    2011-10-01

    The Castanea sativa SCL1 gene (CsSCL1) has previously been shown to be induced by auxin during adventitious root (AR) formation in rooting-competent microshoots. However, its expression has not previously been analyzed in rooting-incompetent shoots. This study focuses on the regulation of CsSCL1 during maturation and the role of the gene in the formation of AR. The expression of CsSCL1 in rooting-incompetent microshoots and other tissues was investigated by quantitative reverse transcriptase--polymerase chain reaction. The analysis was complemented by in situ hybridization of the basal segments of rooting-competent and --incompetent microshoots during AR induction, as well as in AR and lateral roots. It was found that CsSCL1 is upregulated by auxin in a cell-type- and phase-dependent manner during the induction of AR. In root-forming shoots, CsSCL1 mRNA was specifically located in the cambial zone and derivative cells, which are rooting-competent cells, whereas in rooting-incompetent shoots the hybridization signal was more diffuse and evenly distributed through the phloem and parenchyma. CsSCL1 expression was also detected in lateral roots and axillary buds. The different CsSCL1 expression patterns in rooting-competent and -incompetent microshoots, together with the specific location of transcripts in cell types involved in root meristem initiation and in the root primordia of AR and lateral roots, indicate an important role for the gene in determining whether certain cells will enter the root differentiation pathway and its involvement in meristem maintenance.

  9. Differential regulation of caspase-9 by ionizing radiation- and UV-induced apoptotic pathways in thymic cells

    Energy Technology Data Exchange (ETDEWEB)

    Okamoto, Mayumi; Koga, Satomi [Department of Life Sciences, Faculty of Life and Environmental Sciences, Prefectural University of Hiroshima, Hiroshima 727-0023 (Japan); Tatsuka, Masaaki, E-mail: tatsuka@pu-hiroshima.ac.jp [Department of Life Sciences, Faculty of Life and Environmental Sciences, Prefectural University of Hiroshima, Hiroshima 727-0023 (Japan)

    2010-06-01

    In mouse thymic lymphoma 3SB cells bearing wild type p53, ionizing radiation (IR) and UV light are potent triggers of caspase-3-dependent apoptosis. Although cytochrome c was released from mitochondria as expected, caspase-9 activation was not observed in UV-exposed cells. Laser scanning confocal microscopy analysis showed that caspase-9 is localized in an unusual punctuated pattern in UV-induced apoptotic cells. In agreement with differences in the status of caspase-9 activation between IR and UV, subcellular protein fractionation experiments showed that pro-apoptotic apoptosis protease-activating factor 1 (Apaf-1), normally a part of the apoptosome assembled in response to the release of cytochrome c from mitochondria, and B-cell lymphoma extra long (Bcl-xL), an inhibitor of the change in mitochondrial membrane permeability, were redistributed by the IR-exposure but not by the UV-exposure. Instead of the sequestration of the capase-9/apoptosome activation in UV-induced apoptotic cells, the extrinsic apoptotic signaling generated by caspase-8 activation and consequent activation of B-cell lymphoma extra long (Bid) to release cytochrome c from mitochondria was observed. Thus, the post-mitochondrial apoptotic pathway downstream of cytochrome c release cannot operate the apoptosome function in UV-induced apoptosis in thymic 3SB cells. The intracellular redistribution and sequestration of apoptosis-related proteins upon mitochondrion-based apoptotic signaling was identified as a novel cellular mechanism to respond to DNA damage in an agent type-specific manner. This finding suggests that the kind of the critical ultimate apoptosis-inducing DNA lesion complex form resulting from the agent-specific DNA damage responses is important to determine which of apoptosis signals would be activated.

  10. Regulation of the expression of GARP/latent-TGF-β1 complexes on mouse T cells and their role in Regulatory T Cell and Th17 differentiation1

    Science.gov (United States)

    Edwards, Justin P.; Fujii, Hodaka; Zhou, Angela X.; Creemers, John; Unutmaz, Derya; Shevach, Ethan M.

    2013-01-01

    GARP/LRRC32 has previously been defined as a marker of activated human regulatory T-cells (Tregs) that is responsible for surface localization of latent TGF-β1. We find that GARP and latent TGF-β1 are also found on mouse Tregs activated via TCR stimulation, but in contrast to human Tregs, GARP is also expressed at a low level on resting Tregs. The expression of GARP can be upregulated on mouse Tregs by IL-2 or IL-4 exposure in the absence of TCR signaling. GARP is expressed at a low level on Tregs within the thymus and Treg precursors from the thymus concomitantly express GARP and Foxp3 upon exposure to IL-2. The expression of GARP is independent of TGF-β1 and TGF-β1 loading into GARP and is independent of furin-mediated processing of pro-TGF-β1 to latent TGF-β1. Specific deletion of GARP in CD4+ T cells results in lack of expression of latent-TGF-β1 on activated Tregs. GARP-deficient Tregs develop normally, are present in normal numbers in peripheral tissues, and are fully competent suppressors of the activation of T conventional cells in vitro. Activated Tregs expressing GARP/latent-TGF-β1 complexes are potent inducers of Th17 differentiation in the presence of exogenous IL-6 and inducers of Treg in the presence of IL-2. Induction of both Th17 producing cells and Treg is preferentially induced by Tregs expressing the latent-TGF-β1/GARP complex on their cell surface rather than by secreted latent-TGF-β1. PMID:23645881

  11. Regulation of the expression of GARP/latent TGF-β1 complexes on mouse T cells and their role in regulatory T cell and Th17 differentiation.

    Science.gov (United States)

    Edwards, Justin P; Fujii, Hodaka; Zhou, Angela X; Creemers, John; Unutmaz, Derya; Shevach, Ethan M

    2013-06-01

    GARP/LRRC32 was defined as a marker of activated human regulatory T cells (Tregs) that is responsible for surface localization of latent TGF-β1. We find that GARP and latent TGF-β1 are also found on mouse Tregs activated via TCR stimulation; however, in contrast to human Tregs, GARP is also expressed at a low level on resting Tregs. The expression of GARP can be upregulated on mouse Tregs by IL-2 or IL-4 exposure in the absence of TCR signaling. GARP is expressed at a low level on Tregs within the thymus, and Treg precursors from the thymus concomitantly express GARP and Foxp3 upon exposure to IL-2. The expression of GARP is independent of TGF-β1 and TGF-β1 loading into GARP and is independent of furin-mediated processing of pro-TGF-β1 to latent TGF-β1. Specific deletion of GARP in CD4(+) T cells results in lack of expression of latent TGF-β1 on activated Tregs. GARP-deficient Tregs develop normally, are present in normal numbers in peripheral tissues, and are fully competent suppressors of the activation of conventional T cells in vitro. Activated Tregs expressing GARP/latent TGF-β1 complexes are potent inducers of Th17 differentiation in the presence of exogenous IL-6 and inducers of Treg in the presence of IL-2. Induction of both Th17-producing cells and Tregs is caused preferentially by Tregs expressing the latent TGF-β1/GARP complex on their cell surface rather than by secreted latent TGF-β1.

  12. Cyclin D1 negatively regulates the expression of differentiation genes in HT-29 M6 mucus-secreting colon cancer cells.

    Science.gov (United States)

    Mayo, Clara; Mayol, Xavier

    2009-08-28

    HT-29 M6 colon cancer cells differentiate to a mucus-secreting phenotype in culture. We found that the pattern of cyclin D1 expression in HT-29 M6 cells did not correlate with instances of cell proliferation but was specifically induced during a dedifferentiation process following disaggregation of epithelial cell layers, even under conditions that did not allow cell cycle reentrance. Interestingly, ectopic expression of cyclin D1 in differentiated cells led to the inhibition of the transcriptional activity of differentiation gene promoters, such as the mucin MUC1. We thus propose that the overexpression of cyclin D1 found in colon cancer favours tumour dedifferentiation as one mechanism of tumour progression.

  13. Differential regulation by agonist and phorbol ester of cloned m1 and m2 muscarinic acetylcholine receptors in mouse Y1 adrenal cells and in Y1 cells deficient in cAMP-dependent protein kinase

    International Nuclear Information System (INIS)

    Scherer, N.M.; Nathanson, N.M.

    1990-01-01

    Cloned muscarinic acetylcholine m1 and m2 receptors were expressed in stably transfected mouse Y1 adrenal cells and in a variant Y1 line, Kin-8, which is deficient in cAMP-dependent protein kinase activity (PKA - ). m1 and m2 receptors were rapidly internalized following exposure of transfected PKA + or PKA - cells to the muscarinic agonist carbachol. Thus, agonist-dependent internalization of m1 and m2 did not require PKA activity. A differential effect of PKA on regulation by agonist of the m2 receptor, but not the m1 receptor, was unmasked in PKA - cells. These data indicate that the basal activity of PKA may modulate the agonist-dependent internalization of the m2 receptor, but not the m1 receptor. The internalization of the m1 and m2 receptors in both PKA + and PKA - cells was accompanied by desensitization of functional responses. Exposure of PKA + cells to 10 -7 M phorbol 12-myristate 13-acetate (PMA), an activator of protein kinase C, resulted in a 30 ± 9% decrease in the number of m1 receptors on the cell surface. The m2 receptor was not internalized following treatment of either PKA + or PKA - cells with PMA. Thus, the m1 and m2 receptors show differential sensitivity to internalization by PMA. Agonist-dependent internalization of the m1 receptor appeared to be independent of activation of PKC because (1) agonist-dependent internalization of m1 was not attenuated in PKA - cells, (2) the rate and extent of internalization of m1 in cells exposed to PMA were less than those in cells exposed to agonist, and (3) treatment of cells with concanavalin A selectivity blocked internalization of m1 in cells exposed to PMA, but not to agonist. The effects of agonist and PMA on receptor internalization were not additive. Exposure of PKA + or PKA - cells to PMA reduced the magnitude of pilocarpine-stimulated PI hydrolysis by about 25%

  14. Differentially regulated splice variants and systems biology analysis of Kaposi's sarcoma-associated herpesvirus-infected lymphatic endothelial cells.

    Science.gov (United States)

    Chang, Ting-Yu; Wu, Yu-Hsuan; Cheng, Cheng-Chung; Wang, Hsei-Wei

    2011-09-01

    Alternative RNA splicing greatly increases proteome diversity, and the possibility of studying genome-wide alternative splicing (AS) events becomes available with the advent of high-throughput genomics tools devoted to this issue. Kaposi's sarcoma associated herpesvirus (KSHV) is the etiological agent of KS, a tumor of lymphatic endothelial cell (LEC) lineage, but little is known about the AS variations induced by KSHV. We analyzed KSHV-controlled AS using high-density microarrays capable of detecting all exons in the human genome. Splicing variants and altered exon-intron usage in infected LEC were found, and these correlated with protein domain modification. The different 3'-UTR used in new transcripts also help isoforms to escape microRNA-mediated surveillance. Exome-level analysis further revealed information that cannot be disclosed using classical gene-level profiling: a significant exon usage difference existed between LEC and CD34(+) precursor cells, and KSHV infection resulted in LEC-to-precursor, dedifferentiation-like exon level reprogramming. Our results demonstrate the application of exon arrays in systems biology research, and suggest the regulatory effects of AS in endothelial cells are far more complex than previously observed. This extra layer of molecular diversity helps to account for various aspects of endothelial biology, KSHV life cycle and disease pathogenesis that until now have been unexplored.

  15. Nanomaterials modulate stem cell differentiation: biological interaction and underlying mechanisms.

    Science.gov (United States)

    Wei, Min; Li, Song; Le, Weidong

    2017-10-25

    Stem cells are unspecialized cells that have the potential for self-renewal and differentiation into more specialized cell types. The chemical and physical properties of surrounding microenvironment contribute to the growth and differentiation of stem cells and consequently play crucial roles in the regulation of stem cells' fate. Nanomaterials hold great promise in biological and biomedical fields owing to their unique properties, such as controllable particle size, facile synthesis, large surface-to-volume ratio, tunable surface chemistry, and biocompatibility. Over the recent years, accumulating evidence has shown that nanomaterials can facilitate stem cell proliferation and differentiation, and great effort is undertaken to explore their possible modulating manners and mechanisms on stem cell differentiation. In present review, we summarize recent progress in the regulating potential of various nanomaterials on stem cell differentiation and discuss the possible cell uptake, biological interaction and underlying mechanisms.

  16. Proteomic analysis of osteogenic differentiation of dental follicle precursor cells

    DEFF Research Database (Denmark)

    Morsczeck, Christian; Petersen, Jørgen; Völlner, Florian

    2009-01-01

    of differentiation. In the present study we applied 2-DE combined with capillary-LC-MS/MS analysis to profile differentially regulated proteins upon differentiation of dental follicle precursor cells (DFPCs). Out of 115 differentially regulated proteins, glutamine synthetase, lysosomal proteinase cathepsin B....... The bioinformatic analyses suggest that proteins associated with cell cycle progression and protein metabolism were down-regulated and proteins involved in catabolism, cell motility and biological quality were up-regulated. These results display the general physiological state of DFPCs before and after osteogenic...... proteins, plastin 3 T-isoform, beta-actin, superoxide dismutases, and transgelin were found to be highly up-regulated, whereas cofilin-1, pro-alpha 1 collagen, destrin, prolyl 4-hydrolase and dihydrolipoamide dehydrogenase were found to be highly down-regulated. The group of up-regulated proteins...

  17. Alternative Splicing of G9a Regulates Neuronal Differentiation

    Directory of Open Access Journals (Sweden)

    Ana Fiszbein

    2016-03-01

    Full Text Available Chromatin modifications are critical for the establishment and maintenance of differentiation programs. G9a, the enzyme responsible for histone H3 lysine 9 dimethylation in mammalian euchromatin, exists as two isoforms with differential inclusion of exon 10 (E10 through alternative splicing. We find that the G9a methyltransferase is required for differentiation of the mouse neuronal cell line N2a and that E10 inclusion increases during neuronal differentiation of cultured cells, as well as in the developing mouse brain. Although E10 inclusion greatly stimulates overall H3K9me2 levels, it does not affect G9a catalytic activity. Instead, E10 increases G9a nuclear localization. We show that the G9a E10+ isoform is necessary for neuron differentiation and regulates the alternative splicing pattern of its own pre-mRNA, enhancing E10 inclusion. Overall, our findings indicate that by regulating its own alternative splicing, G9a promotes neuron differentiation and creates a positive feedback loop that reinforces cellular commitment to differentiation.

  18. BJ-1108, a 6-Amino-2,4,5-trimethylpyridin-3-ol analogue, regulates differentiation of Th1 and Th17 cells to ameliorate experimental autoimmune encephalomyelitis.

    Science.gov (United States)

    Kang, Youra; Timilshina, Maheshwor; Nam, Tae-Gyu; Jeong, Byeong-Seon; Chang, Jae-Hoon

    2017-02-28

    CD4 + T cells play an important role in the initiation of an immune response by providing help to other cells. Among the helper T subsets, interferon-γ (IFN-γ)-secreting T helper 1 (Th1) and IL-17-secreting T helper 17 (Th17) cells are indispensable for clearance of intracellular as well as extracellular pathogens. However, Th1 and Th17 cells are also associated with pathogenesis and contribute to the progression of multiple inflammatory conditions and autoimmune diseases. In the current study, we found that BJ-1108, a 6-aminopyridin-3-ol analogue, significantly inhibited Th1 and Th17 differentiation in vitro in a concentration-dependent manner, with no effect on proliferation or apoptosis of activated T cells. Moreover, BJ-1108 inhibited differentiation of Th1 and Th17 cells in ovalbumin (OVA)-specific OT II mice. A complete Freund's adjuvant (CFA)/OVA-induced inflammatory model revealed that BJ-1108 can reduce generation of proinflammatory Th1 and Th17 cells. Furthermore, in vivo studies showed that BJ-1108 delayed onset of disease and suppressed experimental autoimmune encephalomyelitis (EAE) disease progression by inhibiting differentiation of Th1 and Th17 cells. BJ-1108 treatment ameliorates inflammation and EAE by inhibiting Th1 and Th17 cells differentiation. Our findings suggest that BJ-1108 is a promising novel therapeutic agent for the treatment of inflammation and autoimmune disease.

  19. Enolase 1 (ENO1 and protein disulfide-isomerase associated 3 (PDIA3 regulate Wnt/β-catenin-driven trans-differentiation of murine alveolar epithelial cells

    Directory of Open Access Journals (Sweden)

    Kathrin Mutze

    2015-08-01

    Full Text Available The alveolar epithelium represents a major site of tissue destruction during lung injury. It consists of alveolar epithelial type I (ATI and type II (ATII cells. ATII cells are capable of self-renewal and exert progenitor function for ATI cells upon alveolar epithelial injury. Cell differentiation pathways enabling this plasticity and allowing for proper repair, however, are poorly understood. Here, we applied proteomics, expression analysis and functional studies in primary murine ATII cells to identify proteins and molecular mechanisms involved in alveolar epithelial plasticity. Mass spectrometry of cultured ATII cells revealed a reduction of carbonyl reductase 2 (CBR2 and an increase in enolase 1 (ENO1 and protein disulfide-isomerase associated 3 (PDIA3 protein expression during ATII-to-ATI cell trans-differentiation. This was accompanied by increased Wnt/β-catenin signaling, as analyzed by qRT-PCR and immunoblotting. Notably, ENO1 and PDIA3, along with T1α (podoplanin; an ATI cell marker, exhibited decreased protein expression upon pharmacological and molecular Wnt/β-catenin inhibition in cultured ATII cells, whereas CBR2 levels were stabilized. Moreover, we analyzed primary ATII cells from mice with bleomycin-induced lung injury, a model exhibiting activated Wnt/β-catenin signaling in vivo. We observed reduced CBR2 significantly correlating with surfactant protein C (SFTPC, whereas ENO1 and PDIA3 along with T1α were increased in injured ATII cells. Finally, siRNA-mediated knockdown of ENO1, as well as PDIA3, in primary ATII cells led to reduced T1α expression, indicating diminished cell trans-differentiation. Our data thus identified proteins involved in ATII-to-ATI cell trans-differentiation and suggest a Wnt/β-catenin-driven functional role of ENO1 and PDIA3 in alveolar epithelial cell plasticity in lung injury and repair.

  20. Conjugated Bilirubin Differentially Regulates CD4+ T Effector Cells and T Regulatory Cell Function through Outside-In and Inside-Out Mechanisms: The Effects of HAV Cell Surface Receptor and Intracellular Signaling

    Science.gov (United States)

    Corral-Jara, Karla F.; Gómez-Leyva, Juan F.; Rosenstein, Yvonne; Jose-Abrego, Alexis; Roman, Sonia

    2016-01-01

    We recently reported an immune-modulatory role of conjugated bilirubin (CB) in hepatitis A virus (HAV) infection. During this infection the immune response relies on CD4+ T lymphocytes (TLs) and it may be affected by the interaction of HAV with its cellular receptor (HAVCR1/TIM-1) on T cell surface. How CB might affect T cell function during HAV infection remains to be elucidated. Herein, in vitro stimulation of CD4+ TLs from healthy donors with CB resulted in a decrease in the degree of intracellular tyrosine phosphorylation and an increase in the activity of T regulatory cells (Tregs) expressing HAVCR1/TIM-1. A comparison between CD4+ TLs from healthy donors and HAV-infected patients revealed changes in the TCR signaling pathway relative to changes in CB levels. The proportion of CD4+CD25+ TLs increased in patients with low CB serum levels and an increase in the percentage of Tregs expressing HAVCR1/TIM-1 was found in HAV-infected patients relative to controls. A low frequency of 157insMTTTVP insertion in the viral receptor gene HAVCR1/TIM-1 was found in patients and controls. Our data revealed that, during HAV infection, CB differentially regulates CD4+ TLs and Tregs functions by modulating intracellular pathways and by inducing changes in the proportion of Tregs expressing HAVCR1/TIM-1. PMID:27578921

  1. Regional up-regulation of NOX2 contributes to the differential vulnerability of outer hair cells to neomycin.

    Science.gov (United States)

    Qi, Meihao; Qiu, Yang; Zhou, Xueying; Tian, Keyong; Zhou, Ke; Sun, Fei; Yue, Bo; Chen, Fuquan; Zha, Dingjun; Qiu, Jianhua

    2018-06-02

    In hearing loss induced by aminoglycoside antibiotics, the outer hair cells (OHCs) in the basal turn are always more susceptible than OHCs in the apical turn, while the underlying mechanisms remain unknown. In this study, we reported that NAPDH oxidase 2 (NOX2) played an important role in the OHCs damage preferentially in the basal turn. Normally, NOX2 was evenly expressed in OHCs among different turns, at a relatively low level. However, after neomycin treatment, NOX2 was dominantly induced in OHCs in the basal turn. In vivo and in vitro studies demonstrated that inhibition of NOX2 significantly alleviated neomycin-induced OHCs damages, as seen from both the cleaved caspase-3 and TUNEL staining. Moreover, gp91 ds-tat delivery and DHE staining results showed that NOX2-derived ROS was responsible for neomycin ototoxicity. Taken together, our study shows that regional up-expression of NOX2 and subsequent increase of ROS in OHCs of the basal turn is an important factor contributing to the vulnerability of OHCs there, which should shed light on the prevention of hearing loss induced by aminoglycoside antibiotics. Copyright © 2018 Elsevier Inc. All rights reserved.

  2. NCAM regulates cell motility

    DEFF Research Database (Denmark)

    Prag, Søren; Lepekhin, Eugene A; Kolkova, Kateryna

    2002-01-01

    Cell migration is required during development of the nervous system. The regulatory mechanisms for this process, however, are poorly elucidated. We show here that expression of or exposure to the neural cell adhesion molecule (NCAM) strongly affected the motile behaviour of glioma cells...... independently of homophilic NCAM interactions. Expression of the transmembrane 140 kDa isoform of NCAM (NCAM-140) caused a significant reduction in cellular motility, probably through interference with factors regulating cellular attachment, as NCAM-140-expressing cells exhibited a decreased attachment...... to a fibronectin substratum compared with NCAM-negative cells. Ectopic expression of the cytoplasmic part of NCAM-140 also inhibited cell motility, presumably via the non-receptor tyrosine kinase p59(fyn) with which NCAM-140 interacts. Furthermore, we showed that the extracellular part of NCAM acted as a paracrine...

  3. Inverse Regulation of Early and Late Chondrogenic Differentiation by Oxygen Tension Provides Cues for Stem Cell-Based Cartilage Tissue Engineering

    Directory of Open Access Journals (Sweden)

    Sophie Portron

    2015-01-01

    Full Text Available Background/Aims: Multipotent stem/stromal cells (MSC are considered promising for cartilage tissue engineering. However, chondrogenic differentiation of MSC can ultimately lead to the formation of hypertrophic chondrocytes responsible for the calcification of cartilage. To prevent the production of this calcified matrix at the articular site, the late hypertrophic differentiation of MSCs must be carefully controlled. Given that articular cartilage is avascular, we hypothesized that in addition to its stimulatory role in the early differentiation of chondrogenic cells, hypoxia may prevent their late hypertrophic conversion. Methods: Early and late chondrogenic differentiation were evaluated using human adipose MSC and murine ATDC5 cells cultured under either normoxic (21%O2 or hypoxic (5%O2 conditions. To investigate the effect of hypoxia on late chondrogenic differentiation, the transcriptional activity of hypoxia-inducible factor-1alpha (HIF-1α and HIF-2α were evaluated using the NoShift DNA-binding assay and through modulation of their activity (chemical inhibitor, RNA interference. Results: Our data demonstrate that low oxygen tension not only stimulates the early chondrogenic commitment of two complementary models of chondrogenic cells, but also inhibits their hypertrophic differentiation. Conclusion: These results suggest that hypoxia can be used as an instrumental tool to prevent the formation of a calcified matrix in MSC-based cartilage tissue engineering.

  4. Delta-like 1/fetal antigen-1 (Dlk1/FA1) is a novel regulator of chondrogenic cell differentiation via inhibition of the Akt kinase-dependent pathway

    DEFF Research Database (Denmark)

    Chen, Li; Qanie, Diyako; Jafari, Abbas

    2011-01-01

    Delta-like 1 (Dlk1, also known as fetal antigen-1, FA1) is a member of Notch/Delta family that inhibits adipocyte and osteoblast differentiation; however, its role in chondrogenesis is still not clear. Thus, we overexpressed Dlk1/FA1 in mouse embryonic ATDC5 cells and tested its effects...... on chondrogenic differentiation. Dlk1/FA1 inhibited insulin-induced chondrogenic differentiation as evidenced by reduction of cartilage nodule formation and gene expression of aggrecan, collagen Type II and X. Similar effects were obtained either by using Dlk1/FA1-conditioned medium or by addition of a purified......, secreted, form of Dlk1 (FA1) directly to the induction medium. The inhibitory effects of Dlk1/FA1 were dose-dependent and occurred irrespective of the chondrogenic differentiation stage: proliferation, differentiation, maturation, or hypertrophic conversion. Overexpression or addition of the Dlk1/FA1...

  5. DNA topoisomerase IIβ stimulates neurite outgrowth in neural differentiated human mesenchymal stem cells through regulation of Rho-GTPases (RhoA/Rock2 pathway) and Nurr1 expression.

    Science.gov (United States)

    Zaim, Merve; Isik, Sevim

    2018-04-25

    DNA topoisomerase IIβ (topo IIβ) is known to regulate neural differentiation by inducing the neuronal genes responsible for critical neural differentiation events such as neurite outgrowth and axon guidance. However, the pathways of axon growth controlled by topo IIβ have not been clarified yet. Microarray results of our previous study have shown that topo IIβ silencing in neural differentiated primary human mesenchymal stem cells (hMSCs) significantly alters the expression pattern of genes involved in neural polarity, axonal growth, and guidance, including Rho-GTPases. This study aims to further analyze the regulatory role of topo IIβ on the process of axon growth via regulation of Rho-GTPases. For this purpose, topo IIβ was silenced in neurally differentiated hMSCs. Cells lost their morphology because of topo IIβ deficiency, becoming enlarged and flattened. Additionally, a reduction in both neural differentiation efficiency and neurite length, upregulation in RhoA and Rock2, downregulation in Cdc42 gene expression were detected. On the other hand, cells were transfected with topo IIβ gene to elucidate the possible neuroprotective effect of topo IIβ overexpression on neural-induced hMSCs. Topo IIβ overexpression prompted all the cells to exhibit neural cell morphology as characterized by longer neurites. RhoA and Rock2 expressions were downregulated, whereas Cdc42 expression was upregulated. Nurr1 expression level correlated with topo IIβ in both topo IIβ-overexpressed and -silenced cells. Furthermore, differential translocation of Rho-GTPases was detected by immunostaining in response to topo IIβ. Our results suggest that topo IIβ deficiency could give rise to neurodegeneration through dysregulation of Rho-GTPases. However, further in-vivo research is needed to demonstrate if re-regulation of Rho GTPases by topo IIβ overexpression could be a neuroprotective treatment in the case of neurodegenerative diseases.

  6. Dickkopf1 Up-Regulation Induced by a High Concentration of Dexamethasone Promotes Rat Tendon Stem Cells to Differentiate Into Adipocytes

    OpenAIRE

    Wan Chen; Hong Tang; Xiangzhou Liu; Mei Zhou; Jiqiang Zhang; Kanglai Tang

    2015-01-01

    Background/Aims: Dexamethasone (Dex)-induced spontaneous tendon rupture and decreased self-repair capability is very common in clinical practice. The metaplasia of adipose tissue in the ruptured tendon indicates that Dex may induce tendon stem cells (TSCs) to differentiate into adipocytes, but the mechanism remains unclear. In the present study, we used in vitro methods to investigate the effects of Dex on rat TSC differentiation and the molecular mechanisms underlying this process. Methods: ...

  7. Distinct bone marrow blood vessels differentially regulate haematopoiesis.

    Science.gov (United States)

    Itkin, Tomer; Gur-Cohen, Shiri; Spencer, Joel A; Schajnovitz, Amir; Ramasamy, Saravana K; Kusumbe, Anjali P; Ledergor, Guy; Jung, Yookyung; Milo, Idan; Poulos, Michael G; Kalinkovich, Alexander; Ludin, Aya; Kollet, Orit; Shakhar, Guy; Butler, Jason M; Rafii, Shahin; Adams, Ralf H; Scadden, David T; Lin, Charles P; Lapidot, Tsvee

    2016-04-21

    Bone marrow endothelial cells (BMECs) form a network of blood vessels that regulate both leukocyte trafficking and haematopoietic stem and progenitor cell (HSPC) maintenance. However, it is not clear how BMECs balance these dual roles, and whether these events occur at the same vascular site. We found that mammalian bone marrow stem cell maintenance and leukocyte trafficking are regulated by distinct blood vessel types with different permeability properties. Less permeable arterial blood vessels maintain haematopoietic stem cells in a low reactive oxygen species (ROS) state, whereas the more permeable sinusoids promote HSPC activation and are the exclusive site for immature and mature leukocyte trafficking to and from the bone marrow. A functional consequence of high permeability of blood vessels is that exposure to blood plasma increases bone marrow HSPC ROS levels, augmenting their migration and differentiation, while compromising their long-term repopulation and survival. These findings may have relevance for clinical haematopoietic stem cell transplantation and mobilization protocols.

  8. Towards spatially differentiated regulation of nitrogen

    DEFF Research Database (Denmark)

    Lajer Højberg, Anker; Refsgaard, Jens Christian; Jørgensen, Lisbeth Flindt

    EU member states are challenged by nitrogen loads to estuaries and inland freshwater systems impeding the achievement of good ecological status as required by the Water Framework Directive (WFD). In Denmark nitrate leaching from the root zone has been reduced by 50% since 1987, but additional...... reductions of 30-50% are required to meet the objectives of the WFD. Achieving such abatements by uniform restrictions for all areas, would be very costly and inefficient as studies have shown that reduction varies spatially depending on the local hydrogeological conditions, the presence and dynamics...... of drains and hydro-biogeochemical conditions in associated riparian lowlands. Hence, a shift of paradigm in regulation practice is needed, whit a cost-effective regulation accounting for this variability and differentiate the regulations/restrictions between resilient and vulnerable areas. However...

  9. Signaling hierarchy regulating human endothelial cell development

    Science.gov (United States)

    Our present knowledge of the regulation of mammalian endothelial cell differentiation has been largely derived from studies of mouse embryonic development. However, unique mechanisms and hierarchy of signals that govern human endothelial cell development are unknown and, thus, explored in these stud...

  10. Regulation of Ca2+ influx by a protein kinase C activator in chromaffin cells: differential role of P/Q- and L-type Ca2+ channels.

    Science.gov (United States)

    Sena, C M; Santos, R M; Boarder, M R; Rosário, L M

    1999-02-05

    Phorbol esters reduce depolarization-evoked Ca2+ influx in adrenal chromaffin cells, suggesting that voltage-sensitive Ca2+ channels (VSCCs) are inhibited by protein kinase C-mediated phosphorylation. We now address the possibility that L- and P/Q-type Ca2+ channel subtypes might be differentially involved in phorbol ester action. In bovine chromaffin cells, short-term (10 min) incubations with phorbol 12-myristate 13-acetate (PMA) inhibited early high K+-evoked rises in cytosolic free Ca2+ concentration ([Ca2+]i) and the early component of the depolarization-evoked Mn2+ quenching of fura-2 fluorescence in a dose-dependent manner (IC50: 18 and 7 nM; maximal inhibitions: 45 and 48%, respectively). The protein kinase C inhibitor staurosporine (100 nM) reverted the inhibitory action of PMA. PMA (0.1-1 microM) inhibited the early and late phases of the ionomycin (2 microM)-evoked [Ca2+]i transients by 14-23%. Omega-agatoxin IVA, a blocker of P/Q-type Ca2+ channels, inhibited high K+-evoked [Ca2+]i rises in a dose-dependent fashion (IC50 = 50 nM). In contrast, 0.1 microM omega-conotoxin GVIA, a blocker of N-type channels, was without effect. A sizeable (< 45%) component of early Ca2+ influx persisted in the combined presence of omega-agatoxin IVA (100 nM) and nitrendipine (1 microM). Simultaneous exposure to omega-agatoxin IVA and PMA inhibited both the early [Ca2+]i transients and Mn2+ quenching to a much greater extent than each drug separately. Inhibition of the [Ca2+]i transients by nitrendipine and PMA did not significantly exceed that produced by PMA alone. It is concluded that phorbol ester-mediated activation of protein kinase C inhibits preferentially L-type VSCCs over P/Q type channels in adrenal chromaffin cells. However, the possibility cannot be ruled out that dihydropyridine-resistant, non-P/Q type channels might also be negatively regulated by protein kinase C. This may represent an important pathway for the specific control of VSCCs by protein kinase C

  11. Mitochondria in aging cell differentiation

    Czech Academy of Sciences Publication Activity Database

    Palková, Zdena; Váchová, Libuše

    2016-01-01

    Roč. 8, č. 7 (2016), s. 1287-1288 ISSN 1945-4589 R&D Projects: GA MŠk(CZ) ED1.1.00/02.0109 Institutional support: RVO:61388971 Keywords : mitochondria * cell differentiation * retrograde signaling Subject RIV: EE - Microbiology, Virology Impact factor: 4.867, year: 2016

  12. Current perspectives in Set7 mediated stem cell differentiation

    Directory of Open Access Journals (Sweden)

    Nazanin Karimnia

    2016-12-01

    Full Text Available Set7 is a key regulatory enzyme involved in the methylation of lysine residues of histone and non-histone proteins. This lysine methyltransferase is induced during stem cell differentiation and regulates lineage specific gene transcription and cell fate. In this article we discuss recent experimental evidence identifying regulatory targets under the control of Set7 as well as emerging evidence of regulation in stem cell differentiation. Furthermore, we discuss the function of non-coding RNAs regulated by Set7 implicated in cell plasticity.

  13. PPARγ isoforms differentially regulate metabolic networks to mediate mouse prostatic epithelial differentiation.

    Science.gov (United States)

    Strand, D W; Jiang, M; Murphy, T A; Yi, Y; Konvinse, K C; Franco, O E; Wang, Y; Young, J D; Hayward, S W

    2012-08-09

    Recent observations indicate prostatic diseases are comorbidities of systemic metabolic dysfunction. These discoveries revealed fundamental questions regarding the nature of prostate metabolism. We previously showed that prostate-specific ablation of PPARγ in mice resulted in tumorigenesis and active autophagy. Here, we demonstrate control of overlapping and distinct aspects of prostate epithelial metabolism by ectopic expression of individual PPARγ isoforms in PPARγ knockout prostate epithelial cells. Expression and activation of either PPARγ 1 or 2 reduced de novo lipogenesis and oxidative stress and mediated a switch from glucose to fatty acid oxidation through regulation of genes including Pdk4, Fabp4, Lpl, Acot1 and Cd36. Differential effects of PPARγ isoforms included decreased basal cell differentiation, Scd1 expression and triglyceride fatty acid desaturation and increased tumorigenicity by PPARγ1. In contrast, PPARγ2 expression significantly increased basal cell differentiation, Scd1 expression and AR expression and responsiveness. Finally, in confirmation of in vitro data, a PPARγ agonist versus high-fat diet (HFD) regimen in vivo confirmed that PPARγ agonization increased prostatic differentiation markers, whereas HFD downregulated PPARγ-regulated genes and decreased prostate differentiation. These data provide a rationale for pursuing a fundamental metabolic understanding of changes to glucose and fatty acid metabolism in benign and malignant prostatic diseases associated with systemic metabolic stress.

  14. Unique B cell differentiation profile in tolerant kidney transplant patients.

    Science.gov (United States)

    Chesneau, M; Pallier, A; Braza, F; Lacombe, G; Le Gallou, S; Baron, D; Giral, M; Danger, R; Guerif, P; Aubert-Wastiaux, H; Néel, A; Michel, L; Laplaud, D-A; Degauque, N; Soulillou, J-P; Tarte, K; Brouard, S

    2014-01-01

    Operationally tolerant patients (TOL) display a higher number of blood B cells and transcriptional B cell signature. As they rarely develop an allo-immune response, they could display an abnormal B cell differentiation. We used an in vitro culture system to explore T-dependent differentiation of B cells into plasma cells. B cell phenotype, apoptosis, proliferation, cytokine, immunoglobulin production and markers of differentiation were followed in blood of these patients. Tolerant recipients show a higher frequency of CD20(+) CD24(hi) CD38(hi) transitional and CD20(+) CD38(lo) CD24(lo) naïve B cells compared to patients with stable graft function, correlating with a decreased frequency of CD20(-) CD38(+) CD138(+) differentiated plasma cells, suggestive of abnormal B cell differentiation. B cells from TOL proliferate normally but produce more IL-10. In addition, B cells from tolerant recipients exhibit a defective expression of factors of the end step of differentiation into plasma cells and show a higher propensity for cell death apoptosis compared to patients with stable graft function. This in vitro profile is consistent with down-regulation of B cell differentiation genes and anti-apoptotic B cell genes in these patients in vivo. These data suggest that a balance between B cells producing IL-10 and a deficiency in plasma cells may encourage an environment favorable to the tolerance maintenance. © Copyright 2013 The American Society of Transplantation and the American Society of Transplant Surgeons.

  15. Regulation of insulin-like growth factor (IGF) I receptor expression during muscle cell differentiation. Potential autocrine role of IGF-II.

    OpenAIRE

    Rosenthal, S M; Brunetti, A; Brown, E J; Mamula, P W; Goldfine, I D

    1991-01-01

    Muscle is an important target tissue for insulin-like growth factor (IGF) action. The presence of specific, high affinity IGF receptors, as well as the expression of IGF peptides and binding proteins by muscle suggest that a significant component of IGF action in this tissue is mediated through autocrine and/or paracrine mechanisms. To explore autocrine/paracrine action of IGFs in muscle, we studied the regulation of the IGF-I receptor and the expression of IGF peptides during differentiation...

  16. Identification and classification of genes regulated by phosphatidylinositol 3-kinase- and TRKB-mediated signalling pathways during neuronal differentiation in two subtypes of the human neuroblastoma cell line SH-SY5Y

    Directory of Open Access Journals (Sweden)

    Sakaki Yoshiyuki

    2008-10-01

    Full Text Available Abstract Background SH-SY5Y cells exhibit a neuronal phenotype when treated with all-trans retinoic acid (RA, but the molecular mechanism of activation in the signalling pathway mediated by phosphatidylinositol 3-kinase (PI3K is unclear. To investigate this mechanism, we compared the gene expression profiles in SK-N-SH cells and two subtypes of SH-SY5Y cells (SH-SY5Y-A and SH-SY5Y-E, each of which show a different phenotype during RA-mediated differentiation. Findings SH-SY5Y-A cells differentiated in the presence of RA, whereas RA-treated SH-SY5Y-E cells required additional treatment with brain-derived neurotrophic factor (BDNF for full differentiation. After exposing cells to a PI3K inhibitor, LY294002, we identified 386 genes and categorised these genes into two clusters dependent on the PI3K signalling pathway during RA-mediated differentiation in SH-SY5Y-A cells. Transcriptional regulation of the gene cluster, including 158 neural genes, was greatly reduced in SK-N-SH cells and partially impaired in SH-SY5Y-E cells, which is consistent with a defect in the neuronal phenotype of these cells. Additional stimulation with BDNF induced a set of neural genes that were down-regulated in RA-treated SH-SY5Y-E cells but were abundant in differentiated SH-SY5Y-A cells. Conclusion We identified gene clusters controlled by PI3K- and TRKB-mediated signalling pathways during the differentiation of two subtypes of SH-SY5Y cells. The TRKB-mediated bypass pathway compensates for impaired neural function generated by defects in several signalling pathways, including PI3K in SH-SY5Y-E cells. Our expression profiling data will be useful for further elucidation of the signal transduction-transcriptional network involving PI3K or TRKB.

  17. Identification and classification of genes regulated by phosphatidylinositol 3-kinase- and TRKB-mediated signalling pathways during neuronal differentiation in two subtypes of the human neuroblastoma cell line SH-SY5Y.

    Science.gov (United States)

    Nishida, Yuichiro; Adati, Naoki; Ozawa, Ritsuko; Maeda, Aasami; Sakaki, Yoshiyuki; Takeda, Tadayuki

    2008-10-28

    SH-SY5Y cells exhibit a neuronal phenotype when treated with all-trans retinoic acid (RA), but the molecular mechanism of activation in the signalling pathway mediated by phosphatidylinositol 3-kinase (PI3K) is unclear. To investigate this mechanism, we compared the gene expression profiles in SK-N-SH cells and two subtypes of SH-SY5Y cells (SH-SY5Y-A and SH-SY5Y-E), each of which show a different phenotype during RA-mediated differentiation. SH-SY5Y-A cells differentiated in the presence of RA, whereas RA-treated SH-SY5Y-E cells required additional treatment with brain-derived neurotrophic factor (BDNF) for full differentiation. After exposing cells to a PI3K inhibitor, LY294002, we identified 386 genes and categorised these genes into two clusters dependent on the PI3K signalling pathway during RA-mediated differentiation in SH-SY5Y-A cells. Transcriptional regulation of the gene cluster, including 158 neural genes, was greatly reduced in SK-N-SH cells and partially impaired in SH-SY5Y-E cells, which is consistent with a defect in the neuronal phenotype of these cells. Additional stimulation with BDNF induced a set of neural genes that were down-regulated in RA-treated SH-SY5Y-E cells but were abundant in differentiated SH-SY5Y-A cells. We identified gene clusters controlled by PI3K- and TRKB-mediated signalling pathways during the differentiation of two subtypes of SH-SY5Y cells. The TRKB-mediated bypass pathway compensates for impaired neural function generated by defects in several signalling pathways, including PI3K in SH-SY5Y-E cells. Our expression profiling data will be useful for further elucidation of the signal transduction-transcriptional network involving PI3K or TRKB.

  18. Redox regulation of plant stem cell fate.

    Science.gov (United States)

    Zeng, Jian; Dong, Zhicheng; Wu, Haijun; Tian, Zhaoxia; Zhao, Zhong

    2017-10-02

    Despite the importance of stem cells in plant and animal development, the common mechanisms of stem cell maintenance in both systems have remained elusive. Recently, the importance of hydrogen peroxide (H 2 O 2 ) signaling in priming stem cell differentiation has been extensively studied in animals. Here, we show that different forms of reactive oxygen species (ROS) have antagonistic roles in plant stem cell regulation, which were established by distinct spatiotemporal patterns of ROS-metabolizing enzymes. The superoxide anion (O2·-) is markedly enriched in stem cells to activate WUSCHEL and maintain stemness, whereas H 2 O 2 is more abundant in the differentiating peripheral zone to promote stem cell differentiation. Moreover, H 2 O 2 negatively regulates O2·- biosynthesis in stem cells, and increasing H 2 O 2 levels or scavenging O2·- leads to the termination of stem cells. Our results provide a mechanistic framework for ROS-mediated control of plant stem cell fate and demonstrate that the balance between O2·- and H 2 O 2 is key to stem cell maintenance and differentiation. © 2017 The Authors.

  19. Signaling hierarchy regulating human endothelial cell development.

    Science.gov (United States)

    Kelly, Melissa A; Hirschi, Karen K

    2009-05-01

    Our present knowledge of the regulation of mammalian endothelial cell differentiation has been largely derived from studies of mouse embryonic development. However, unique mechanisms and hierarchy of signals that govern human endothelial cell development are unknown and, thus, explored in these studies. Using human embryonic stem cells as a model system, we were able to reproducibly and robustly generate differentiated endothelial cells via coculture on OP9 marrow stromal cells. We found that, in contrast to studies in the mouse, bFGF and VEGF had no specific effects on the initiation of human vasculogenesis. However, exogenous Ihh promoted endothelial cell differentiation, as evidenced by increased production of cells with cobblestone morphology that coexpress multiple endothelial-specific genes and proteins, form lumens, and exhibit DiI-AcLDL uptake. Inhibition of BMP signaling using Noggin or BMP4, specifically, using neutralizing antibodies suppressed endothelial cell formation; whereas, addition of rhBMP4 to cells treated with the hedgehog inhibitor cyclopamine rescued endothelial cell development. Our studies revealed that Ihh promoted human endothelial cell differentiation from pluripotent hES cells via BMP signaling, providing novel insights applicable to modulating human endothelial cell formation and vascular regeneration for human clinical therapies.

  20. Topographical cues of direct metal laser sintering titanium surfaces facilitate osteogenic differentiation of bone marrow mesenchymal stem cells through epigenetic regulation.

    Science.gov (United States)

    Zheng, Guoying; Guan, Binbin; Hu, Penghui; Qi, Xingying; Wang, Pingting; Kong, Yu; Liu, Zihao; Gao, Ping; Li, Rui; Zhang, Xu; Wu, Xudong; Sui, Lei

    2018-04-27

    To investigate the role of hierarchical micro/nanoscale topography of direct metal laser sintering (DMLS) titanium surfaces in osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs), as well as the possible underlying epigenetic mechanism. Three groups of titanium specimens were prepared, including DMLS group, sandblasted, large-grit, acid-etched (SLA) group and smooth titanium (Ti) group. BMSCs were cultured on discs followed by surface characterization. Cell adhesion and proliferation were examined by SEM and CCK-8 assay, while osteogenic-related gene expression was detected by real-time RT-PCR. Immunofluorescence, western blotting and in vivo study were also performed to evaluate the potential for osteogenic induction of materials. In addition, to investigate the underlying epigenetic mechanisms, immunofluorescence and western blotting were performed to evaluate the global level of H3K4me3 during osteogenesis. The H3K4me3 and H3K27me3 levels at the promoter area of the osteogenic gene Runx2 were detected by ChIP assay. The DMLS surface exhibits greater protein adsorption ability and shows better cell adhesion performance than SLA and Ti surfaces. Moreover, both in vitro and in vivo studies demonstrated that the DMLS surface is more favourable for the osteogenic differentiation of BMSCs than SLA and Ti surfaces. Accordingly, osteogenesis-associated gene expression in BMSCs is efficiently induced by a rapid H3K27 demethylation and increase in H3K4me3 levels at gene promoters upon osteogenic differentiation on DMLS titanium surface. Topographical cues of DMLS surfaces have greater potential for the induction of osteogenic differentiation of BMSCs than SLA and Ti surfaces both in vitro and in vivo. A potential epigenetic mechanism is that the appropriate topography allows rapid H3K27 demethylation and an increased H3K4me3 level at the promoter region of osteogenesis-associated genes during the osteogenic differentiation of BMSCs. © 2018 John Wiley

  1. Cell fate regulation in the shoot meristem.

    Science.gov (United States)

    Laux, T; Mayer, K F

    1998-04-01

    The shoot meristem is a proliferative centre containing pluripotent stem cells that are the ultimate source of all cells and organs continuously added to the growing shoot. The progeny of the stem cells have two developmental options, either to renew the stem cell population or to leave the meristem and to differentiate, possibly according to signals from more mature tissue. The destiny of each cell depends on its position within the dynamic shoot meristem. Genetic data suggest a simple model in which graded positional information is provided by antagonistic gene functions and is interpreted by genes which regulate cell fate.

  2. Ghrelin O-acyltransferase (GOAT) is expressed in prostate cancer tissues and cell lines and expression is differentially regulated in vitro by ghrelin

    Science.gov (United States)

    2013-01-01

    Background Ghrelin is a 28 amino acid peptide hormone that is expressed in the stomach and a range of peripheral tissues, where it frequently acts as an autocrine/paracrine growth factor. Ghrelin is modified by a unique acylation required for it to activate its cognate receptor, the growth hormone secretagogue receptor (GHSR), which mediates many of the actions of ghrelin. Recently, the enzyme responsible for adding the fatty acid residue (octanoyl/acyl group) to the third amino acid of ghrelin, GOAT (ghrelin O-acyltransferase), was identified. Methods We used cell culture, quantitative real-time reverse transcription (RT)-PCR and immunohistochemistry to demonstrate the expression of GOAT in prostate cancer cell lines and tissues from patients. Real-time RT-PCR was used to demonstrate the expression of prohormone convertase (PC)1/3, PC2 and furin in prostate cancer cell lines. Prostate-derived cell lines were treated with ghrelin and desacyl ghrelin and the effect on GOAT expression was measured using quantitative RT-PCR. Results We have demonstrated that GOAT mRNA and protein are expressed in the normal prostate and human prostate cancer tissue samples. The RWPE-1 and RWPE-2 normal prostate-derived cell lines and the LNCaP, DU145, and PC3 prostate cancer cell lines express GOAT and at least one other enzyme that is necessary to produce mature, acylated ghrelin from proghrelin (PC1/3, PC2 or furin). Finally, ghrelin, but not desacyl ghrelin (unacylated ghrelin), can directly regulate the expression of GOAT in the RWPE-1 normal prostate derived cell line and the PC3 prostate cancer cell line. Ghrelin treatment (100nM) for 6 hours significantly decreased GOAT mRNA expression two-fold (P ghrelin did not regulate GOAT expression in the DU145 and LNCaP prostate cancer cell lines. Conclusions This study demonstrates that GOAT is expressed in prostate cancer specimens and cell lines. Ghrelin regulates GOAT expression, however, this is likely to be cell-type specific

  3. miR-140-5p regulates hypoxia-mediated human pulmonary artery smooth muscle cell proliferation, apoptosis and differentiation by targeting Dnmt1 and promoting SOD2 expression

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yanwei; Xu, Jing, E-mail: xujingdoc@163.com

    2016-04-22

    miR-140-5p is down-regulated in patients with pulmonary arterial hypertension (PAH) and experimental models of PAH, and inhibits hypoxia-mediated pulmonary artery smooth muscle cell (PASMC) proliferation in vitro. Delivery of synthetic miR-140-5p prevents and treats established, experimental PAH. DNA methyltransferase 1 (Dnmt1) is up-regulated in PAH associated human PASMCs (HPASMCs), which promotes the development of PAH by hypermethylation of CpG islands within the promoter for superoxide dismutase 2 (SOD2) and down-regulating SOD2 expression. We searched for miR-140-5p targets using TargetScan, PicTar and MiRanda tools, and found that Dnmt1 is a potential target of miR-140-5p. Based on these findings, we speculated that miR-140-5p might target Dnmt1 and regulate SOD2 expression to regulate hypoxia-mediated HPASMC proliferation, apoptosis and differentiation. We detected the expression of miR-140-5p, Dnmt1 and SOD2 by quantitative real-time polymerase chain reaction (qRT-PCR) and western blot assays, respectively, and found down-regulation of miR-140-5p and SOD2 and up-regulation of Dnmt1 exist in PAH tissues and hypoxia-mediated HPASMCs. Cell proliferation, apoptosis and differentiation detection showed that miR-140-5p inhibits proliferation and promotes apoptosis and differentiation of HPASMCs in hypoxia, while the effect of Dnmt1 on hypoxia-mediated HPASMCs is reversed. Luciferase assay confirmed that miR-140-5p targets Dnmt1 directly. An inverse correlation is also found between miR-140-5p and Dnmt1 in HPASMCs. In addition, we further investigated whether miR-140-5p and Dnmt1 regulate HPASMC proliferation, apoptosis and differentiation by regulating SOD2 expression, and the results confirmed our speculation. Taken together, these results indicated that miR-140-5p at least partly targets Dnmt1 and regulates SOD2 expression to inhibit proliferation and promote apoptosis and differentiation of HPASMCs in hypoxia. - Highlights: • miR-140-5p and SOD2 are down-regulated

  4. Downregulation of rRNA transcription triggers cell differentiation.

    Directory of Open Access Journals (Sweden)

    Yuki Hayashi

    Full Text Available Responding to various stimuli is indispensable for the maintenance of homeostasis. The downregulation of ribosomal RNA (rRNA transcription is one of the mechanisms involved in the response to stimuli by various cellular processes, such as cell cycle arrest and apoptosis. Cell differentiation is caused by intra- and extracellular stimuli and is associated with the downregulation of rRNA transcription as well as reduced cell growth. The downregulation of rRNA transcription during differentiation is considered to contribute to reduced cell growth. However, the downregulation of rRNA transcription can induce various cellular processes; therefore, it may positively regulate cell differentiation. To test this possibility, we specifically downregulated rRNA transcription using actinomycin D or a siRNA for Pol I-specific transcription factor IA (TIF-IA in HL-60 and THP-1 cells, both of which have differentiation potential. The inhibition of rRNA transcription induced cell differentiation in both cell lines, which was demonstrated by the expression of the common differentiation marker CD11b. Furthermore, TIF-IA knockdown in an ex vivo culture of mouse hematopoietic stem cells increased the percentage of myeloid cells and reduced the percentage of immature cells. We also evaluated whether differentiation was induced via the inhibition of cell cycle progression because rRNA transcription is tightly coupled to cell growth. We found that cell cycle arrest without affecting rRNA transcription did not induce differentiation. To the best of our knowledge, our results demonstrate the first time that the downregulation of rRNA levels could be a trigger for the induction of differentiation in mammalian cells. Furthermore, this phenomenon was not simply a reflection of cell cycle arrest. Our results provide a novel insight into the relationship between rRNA transcription and cell differentiation.

  5. Redox regulation in cancer stem cells

    Science.gov (United States)

    Reactive oxygen species (ROS) and ROS-dependent (redox regulation) signaling pathways and transcriptional activities are thought to be critical in stem cell self-renewal and differentiation during growth and organogenesis. Aberrant ROS burst and dysregulation of those ROS-dependent cellular processe...

  6. Epidermal cell-shape regulation and subpopulation kinetics during butyrate-induced terminal maturation of normal and SV40-transformed human keratinocytes: epithelial models of differentiation therapy.

    Science.gov (United States)

    Staiano-Coico, L; Steinberg, M; Higgins, P J

    1990-10-15

    Recent data indicate that malignant human epidermal cells may be appropriate targets for sodium butyrate (NaB)-mediated differentiation therapy. The response of pre- and post-crisis populations of SV40-transformed human keratinocytes (SVKs) to this differentiation-inducing agent was assessed, therefore, within the framework of NaB-directed normal human keratinocyte (NHK) maturation. NaB augmented cornified envelope (CE) production in NHK and pre-crisis SVK cultures; the time-course and efficiency of induced maturation were similar in the 2 cell systems. In NHKs, the percentage of amplifying ("B" substate) cells decreased with time in NaB correlating with increases in both "C" stage keratinocytes and CEs. The latter formed over one or 2 layers of nucleated basal-like cells. Inductions were accompanied by immediate cell cycle blocks (in both the G1 and G2/M phases), reorganization within the actin cytoskeleton, and transient early increases in cellular actin content. Increased NHK and pre-crisis SVK cytoskeletal-associated actin reached a maximum approximately 48 hr after NaB addition and preceded development of CEs. The CE precursors, thus, probably reside in the "B" substate. Post-crisis SVKs, in contrast, were refractive to NaB-induced terminal maturation or cell-cycle perturbation, failed to initiate actin filament rearrangements, and retained a basal cell-like phenotype. Stable transformation of human SVKs in post-crisis phase, therefore, appears to be associated with loss of maturation "competence" within the "B" keratinocyte subpopulation.

  7. Neem leaf glycoprotein prevents post-surgical sarcoma recurrence in Swiss mice by differentially regulating cytotoxic T and myeloid-derived suppressor cells.

    Directory of Open Access Journals (Sweden)

    Madhurima Sarkar

    Full Text Available Post-surgical tumor recurrence is a common problem in cancer treatment. In the present study, the role of neem leaf glycoprotein (NLGP, a novel immunomodulator, in prevention of post-surgical recurrence of solid sarcoma was examined. Data suggest that NLGP prevents tumor recurrence after surgical removal of sarcoma in Swiss mice and increases their tumor-free survival time. In NLGP-treated tumor-free mice, increased cytotoxic CD8+ T cells and a decreased population of suppressor cells, especially myeloid-derived suppressor cells (MDSCs was observed. NLGP-treated CD8+ T cells showed greater cytotoxicity towards tumor-derived MDSCs and supernatants from the same CD8+ T cell culture caused upregulation of FasR and downregulation of cFLIP in MDSCs. To elucidate the role of CD8+ T cells, specifically in association with the downregulation in MDSCs, CD8+ T cells were depleted in vivo before NLGP immunization in surgically tumor removed mice and tumor recurrence was noted. These mice also exhibited increased MDSCs along with decreased levels of Caspase 3, Caspase 8 and increased cFLIP expression. In conclusion, it can be stated that NLGP, by activating CD8+ T cells, down regulates the proportion of MDSCs. Accordingly, suppressive effects of MDSCs on CD8+ T cells are minimized and optimum immune surveillance in tumor hosts is maintained to eliminate the residual tumor mass appearing during recurrence.

  8. Lineage-specific interface proteins match up the cell cycle and differentiation in embryo stem cells

    DEFF Research Database (Denmark)

    Re, Angela; Workman, Christopher; Waldron, Levi

    2014-01-01

    The shortage of molecular information on cell cycle changes along embryonic stem cell (ESC) differentiation prompts an in silico approach, which may provide a novel way to identify candidate genes or mechanisms acting in coordinating the two programs. We analyzed germ layer specific gene expression...... changes during the cell cycle and ESC differentiation by combining four human cell cycle transcriptome profiles with thirteen in vitro human ESC differentiation studies. To detect cross-talk mechanisms we then integrated the transcriptome data that displayed differential regulation with protein...... interaction data. A new class of non-transcriptionally regulated genes was identified, encoding proteins which interact systematically with proteins corresponding to genes regulated during the cell cycle or cell differentiation, and which therefore can be seen as interface proteins coordinating the two...

  9. In vivo regulation of colonic cell proliferation, differentiation, apoptosis, and P27Kip1 by dietary fish oil and butyrate in rats.

    Science.gov (United States)

    Hong, Mee Young; Turner, Nancy D; Murphy, Mary E; Carroll, Raymond J; Chapkin, Robert S; Lupton, Joanne R

    2015-11-01

    We have shown that dietary fish oil is protective against experimentally induced colon cancer, and the protective effect is enhanced by coadministration of pectin. However, the underlying mechanisms have not been fully elucidated. We hypothesized that fish oil with butyrate, a pectin fermentation product, protects against colon cancer initiation by decreasing cell proliferation and increasing differentiation and apoptosis through a p27(Kip1)-mediated mechanism. Rats were provided diets of corn or fish oil, with/without butyrate, and terminated 12, 24, or 48 hours after azoxymethane (AOM) injection. Proliferation (Ki-67), differentiation (Dolichos Biflorus Agglutinin), apoptosis (TUNEL), and p27(Kip1) (cell-cycle mediator) were measured in the same cell within crypts in order to examine the coordination of cell cycle as a function of diet. DNA damage (N(7)-methylguanine) was determined by quantitative IHC analysis. Dietary fish oil decreased DNA damage by 19% (P = 0.001) and proliferation by 50% (P = 0.003) and increased differentiation by 56% (P = 0.039) compared with corn oil. When combined with butyrate, fish oil enhanced apoptosis 24 hours after AOM injection compared with a corn oil/butyrate diet (P = 0.039). There was an inverse relationship between crypt height and apoptosis in the fish oil/butyrate group (r = -0.53, P = 0.040). The corn oil/butyrate group showed a positive correlation between p27(Kip1) expression and proliferation (r = 0.61, P = 0.035). These results indicate the in vivo effect of butyrate on apoptosis and proliferation is dependent on dietary lipid source. These results demonstrate the presence of an early coordinated colonocyte response by which fish oil and butyrate protects against colon tumorigenesis. ©2015 American Association for Cancer Research.

  10. Palmitoylation regulates epidermal homeostasis and hair follicle differentiation.

    Directory of Open Access Journals (Sweden)

    Pleasantine Mill

    2009-11-01

    Full Text Available Palmitoylation is a key post-translational modification mediated by a family of DHHC-containing palmitoyl acyl-transferases (PATs. Unlike other lipid modifications, palmitoylation is reversible and thus often regulates dynamic protein interactions. We find that the mouse hair loss mutant, depilated, (dep is due to a single amino acid deletion in the PAT, Zdhhc21, resulting in protein mislocalization and loss of palmitoylation activity. We examined expression of Zdhhc21 protein in skin and find it restricted to specific hair lineages. Loss of Zdhhc21 function results in delayed hair shaft differentiation, at the site of expression of the gene, but also leads to hyperplasia of the interfollicular epidermis (IFE and sebaceous glands, distant from the expression site. The specific delay in follicle differentiation is associated with attenuated anagen propagation and is reflected by decreased levels of Lef1, nuclear beta-catenin, and Foxn1 in hair shaft progenitors. In the thickened basal compartment of mutant IFE, phospho-ERK and cell proliferation are increased, suggesting increased signaling through EGFR or integrin-related receptors, with a parallel reduction in expression of the key differentiation factor Gata3. We show that the Src-family kinase, Fyn, involved in keratinocyte differentiation, is a direct palmitoylation target of Zdhhc21 and is mislocalized in mutant follicles. This study is the first to demonstrate a key role for palmitoylation in regulating developmental signals in mammalian tissue homeostasis.

  11. Non-genetic heterogeneity, criticality and cell differentiation.

    Science.gov (United States)

    Pal, Mainak; Ghosh, Sayantari; Bose, Indrani

    2014-11-27

    The different cell types in a living organism acquire their identity through the process of cell differentiation in which multipotent progenitor cells differentiate into distinct cell types. Experimental evidence and analysis of large-scale microarray data establish the key role played by a two-gene motif in cell differentiation in a number of cell systems. The two genes express transcription factors which repress each other's expression and autoactivate their own production. A number of theoretical models have recently been proposed based on the two-gene motif to provide a physical understanding of how cell differentiation occurs. In this paper, we study a simple model of cell differentiation which assumes no cooperativity in the regulation of gene expression by the transcription factors. The latter repress each other's activity directly through DNA binding and indirectly through the formation of heterodimers. We specifically investigate how deterministic processes combined with stochasticity contribute in bringing about cell differentiation. The deterministic dynamics of our model give rise to a supercritical pitchfork bifurcation from an undifferentiated stable steady state to two differentiated stable steady states. The stochastic dynamics of our model are studied using the approaches based on the Langevin equations and the linear noise approximation. The simulation results provide a new physical understanding of recent experimental observations. We further propose experimental measurements of quantities like the variance and the lag-1 autocorrelation function in protein fluctuations as the early signatures of an approaching bifurcation point in the cell differentiation process.

  12. Regulation of C/EBPβ isoforms by MAPK pathways in HL60 cells induced to differentiate by 1,25-dihydroxyvitamin D3

    International Nuclear Information System (INIS)

    Marcinkowska, Ewa; Garay, Edward; Gocek, Elzbieta; Chrobak, Agnieszka; Wang, Xuening; Studzinski, George P.

    2006-01-01

    C/EBPβ is known to be important for monocytic differentiation and macrophage function. Here, we found that expression of all three C/EBPβ isoforms induced in HL60 cells by 1,25-dihydroxyvitamin D 3 (1,25D) was upregulated in a sustained manner that correlates with the appearance of monocytic phenotype and with the G1 phase cell cycle arrest. In 1,25D-resistant HL60-40AF cells, isoforms β-1 and β-3 were expressed at levels comparable to 1,25D-sensitive HL60-G cells, but isoform β-2 was difficult to detect. Treatment of sensitive HL60 cells with 1,25D resulted in predominantly nuclear localization of C/EBP isoforms β-2 and β-3, while a large proportion of C/EBPβ-1 remained in the cytoplasm. Attenuation of the MEK-ERK MAPK pathway by the inhibitor PD98059 markedly reduced the expression, 1,25D-induced phosphorylation and nuclear localization of C/EBPβ-2 and C/EBPβ-3. Interestingly, only the lower molecular mass isoforms of C/EBPβ phosphorylated on Thr235 were found in the nuclei, while C/EBPβ-1 was constitutively phosphorylated and was detected principally in the cytoplasmic fraction. Although the role of C/EBPβ isoforms in 1,25D-induced differentiation is complex, our results taken together strongly suggest that the phosphorylation of C/EBPβ isoforms on Thr235 takes place mainly via the MEK-ERK pathway and that C/EBPβ-2 is the principal transcription factor in this cell system

  13. 4-(E)-{(p-tolylimino)-methylbenzene-1,2-diol}, 1 a novel resveratrol analog, differentially regulates estrogen receptors α and β in breast cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Ronghe, Amruta; Chatterjee, Anwesha [Division of Pharmacology and Toxicology, School of Pharmacy, University of Missouri-Kansas City, Kansas City, MO 64108 (United States); Singh, Bhupendra [Department of Genetics, School of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294 (United States); Dandawate, Prasad [ISTRA, Department of Chemistry, Abeda Inamdar Senior College, University of Pune (India); Abdalla, Fatma; Bhat, Nimee K. [Division of Pharmacology and Toxicology, School of Pharmacy, University of Missouri-Kansas City, Kansas City, MO 64108 (United States); Padhye, Subhash [ISTRA, Department of Chemistry, Abeda Inamdar Senior College, University of Pune (India); Bhat, Hari K., E-mail: bhath@umkc.edu [Division of Pharmacology and Toxicology, School of Pharmacy, University of Missouri-Kansas City, Kansas City, MO 64108 (United States)

    2016-06-15

    Breast cancer is a public health concern worldwide. Prolonged exposure to estrogens has been implicated in the development of breast neoplasms. Epidemiologic and experimental evidence suggest a chemopreventive role of phytoestrogens in breast cancers. Resveratrol, a naturally occurring phytoestrogen, has been shown to have potent anti-cancer properties. However, poor efficacy and bioavailability have prevented the use of resveratrol in clinics. In order to address these problems, we have synthesized a combinatorial library of azaresveratrol analogs and tested them for their ability to inhibit the proliferation of breast cancer cells. We have recently shown that 4-(E)-{(p-tolylimino)-methylbenzene-1,2-diol} (TIMBD), has better anti-cancer properties than resveratrol and any other resveratrol analog we have synthesized so far. The objective of this study was to investigate the regulation of estrogen receptors (ERs) α and β by TIMBD in breast cancer cell lines. We demonstrate that TIMBD significantly induces the mRNA and protein expression levels of ERβ and inhibits that of ERα. TIMBD inhibits mRNA and protein expression levels of oncogene c-Myc, and cell cycle protein cyclin D1, which are important regulators of cellular proliferation. TIMBD significantly induces protein expression levels of tumor suppressor genes p53 and p21 in MCF-7 cells. TIMBD inhibits c-Myc in an ERβ-dependent fashion in MCF-10 A and ERβ1-transfected MDA-MB-231 cells, suggesting regulation of ERs as an important upstream mechanism of this analog. ERβ plays a partial role in inhibition of proliferation by TIMBD while ERα overexpression does not significantly affect TIMBD's inhibition. - Highlights: • Resveratrol analog TIMBD inhibits growth of breast cancer cells. • TIMBD induces protein expression levels of ERβ and inhibits that of ERα. • TIMBD inhibits c-Myc and cyclin D1, and induces p53 and p21. • TIMBD suppresses c-Myc in an ER-dependent fashion.

  14. 4-(E)-{(p-tolylimino)-methylbenzene-1,2-diol}, 1 a novel resveratrol analog, differentially regulates estrogen receptors α and β in breast cancer cells

    International Nuclear Information System (INIS)

    Ronghe, Amruta; Chatterjee, Anwesha; Singh, Bhupendra; Dandawate, Prasad; Abdalla, Fatma; Bhat, Nimee K.; Padhye, Subhash; Bhat, Hari K.

    2016-01-01

    Breast cancer is a public health concern worldwide. Prolonged exposure to estrogens has been implicated in the development of breast neoplasms. Epidemiologic and experimental evidence suggest a chemopreventive role of phytoestrogens in breast cancers. Resveratrol, a naturally occurring phytoestrogen, has been shown to have potent anti-cancer properties. However, poor efficacy and bioavailability have prevented the use of resveratrol in clinics. In order to address these problems, we have synthesized a combinatorial library of azaresveratrol analogs and tested them for their ability to inhibit the proliferation of breast cancer cells. We have recently shown that 4-(E)-{(p-tolylimino)-methylbenzene-1,2-diol} (TIMBD), has better anti-cancer properties than resveratrol and any other resveratrol analog we have synthesized so far. The objective of this study was to investigate the regulation of estrogen receptors (ERs) α and β by TIMBD in breast cancer cell lines. We demonstrate that TIMBD significantly induces the mRNA and protein expression levels of ERβ and inhibits that of ERα. TIMBD inhibits mRNA and protein expression levels of oncogene c-Myc, and cell cycle protein cyclin D1, which are important regulators of cellular proliferation. TIMBD significantly induces protein expression levels of tumor suppressor genes p53 and p21 in MCF-7 cells. TIMBD inhibits c-Myc in an ERβ-dependent fashion in MCF-10 A and ERβ1-transfected MDA-MB-231 cells, suggesting regulation of ERs as an important upstream mechanism of this analog. ERβ plays a partial role in inhibition of proliferation by TIMBD while ERα overexpression does not significantly affect TIMBD's inhibition. - Highlights: • Resveratrol analog TIMBD inhibits growth of breast cancer cells. • TIMBD induces protein expression levels of ERβ and inhibits that of ERα. • TIMBD inhibits c-Myc and cyclin D1, and induces p53 and p21. • TIMBD suppresses c-Myc in an ER-dependent fashion.

  15. Heterokaryon analysis of muscle differentiation: regulation of the postmitotic state.

    Science.gov (United States)

    Clegg, C H; Hauschka, S D

    1987-08-01

    MM14 mouse myoblasts withdraw irreversibly from the cell cycle and become postmitotic within a few hours of being deprived of fibroblast growth factor (Clegg, C. H., T. A. Linkhart, B. B. Olwin, and S. D. Hauschka, 1987, J. Cell Biol., 105:949-956). To examine the mechanisms that may regulate this developmental state of skeletal muscle, we tested the mitogen responsiveness of various cell types after their polyethylene glycol-mediated fusion with post-mitotic myocytes. Heterokaryons containing myocytes and quiescent nonmyogenic cells such as 3T3, L cell, and a differentiation-defective myoblast line (DD-1) responded to mitogen-rich medium by initiating DNA synthesis. Myonuclei replicated DNA and reexpressed thymidine kinase. In contrast, (myocyte x G1 myoblast) heterokaryons failed to replicate DNA in mitogen-rich medium and became postmitotic. This included cells with a nuclear ratio of three myoblasts to one myocyte. Proliferation dominance in (myocyte x 3T3 cell) and (myocyte x DD-1) heterokaryons was conditionally regulated by the timing of mitogen treatment; such cells became postmitotic when mitogen exposure was delayed for as little as 6 h after cell fusion. In addition, (myocyte x DD-1) heterokaryons expressed a muscle-specific trait and lost epidermal growth factor receptors when they became postmitotic. These results demonstrate that DNA synthesis is not irreversibly blocked in skeletal muscle; myonuclei readily express proliferation-related functions when provided with a mitogenic signal. Rather, myocyte-specific repression of DNA synthesis in heterokaryons argues that the postmitotic state of skeletal muscle is regulated by diffusible factors that inhibit processes of cellular mitogenesis.

  16. Cell Cycle Regulation of Stem Cells by MicroRNAs.

    Science.gov (United States)

    Mens, Michelle M J; Ghanbari, Mohsen

    2018-06-01

    MicroRNAs (miRNAs) are a class of small non-coding RNA molecules involved in the regulation of gene expression. They are involved in the fine-tuning of fundamental biological processes such as proliferation, differentiation, survival and apoptosis in many cell types. Emerging evidence suggests that miRNAs regulate critical pathways involved in stem cell function. Several miRNAs have been suggested to target transcripts that directly or indirectly coordinate the cell cycle progression of stem cells. Moreover, previous studies have shown that altered expression levels of miRNAs can contribute to pathological conditions, such as cancer, due to the loss of cell cycle regulation. However, the precise mechanism underlying miRNA-mediated regulation of cell cycle in stem cells is still incompletely understood. In this review, we discuss current knowledge of miRNAs regulatory role in cell cycle progression of stem cells. We describe how specific miRNAs may control cell cycle associated molecules and checkpoints in embryonic, somatic and cancer stem cells. We further outline how these miRNAs could be regulated to influence cell cycle progression in stem cells as a potential clinical application.

  17. Regulation of the expression of GARP/latent-TGF-β1 complexes on mouse T cells and their role in Regulatory T Cell and Th17 differentiation1

    OpenAIRE

    Edwards, Justin P.; Fujii, Hodaka; Zhou, Angela X.; Creemers, John; Unutmaz, Derya; Shevach, Ethan M.

    2013-01-01

    GARP/LRRC32 has previously been defined as a marker of activated human regulatory T-cells (Tregs) that is responsible for surface localization of latent TGF-β1. We find that GARP and latent TGF-β1 are also found on mouse Tregs activated via TCR stimulation, but in contrast to human Tregs, GARP is also expressed at a low level on resting Tregs. The expression of GARP can be upregulated on mouse Tregs by IL-2 or IL-4 exposure in the absence of TCR signaling. GARP is expressed at a low level on ...

  18. Differential Expression and Regulation of Brain-Derived Neurotrophic Factor (BDNF) mRNA Isoforms in Brain Cells from Mecp2(308/y) Mouse Model.

    Science.gov (United States)

    Rousseaud, Audrey; Delépine, Chloé; Nectoux, Juliette; Billuart, Pierre; Bienvenu, Thierry

    2015-08-01

    Rett syndrome (RTT) is a severe neurodevelopmental disease caused by mutations in methyl-CpG-binding protein 2 (MECP2), which encodes a transcriptional modulator of many genes including BDNF. BDNF comprises nine distinct promoter regions, each triggering the expression of a specific transcript. The role of this diversity of transcripts remains unknown. MeCP2 being highly expressed in neurons, RTT was initially considered as a neuronal disease. However, recent studies have shown that MeCP2 was also expressed in astrocytes. Though several studies explored Bdnf IV expression in Mecp2-deficient mice, the differential expression of Bdnf isoforms in Mecp2-deficient neurons and astrocytes was never studied. By using TaqMan technology and a mouse model expressing a truncated Mecp2 (Mecp2(308/y)), we firstly showed in neurons that Bdnf transcripts containing exon I, IIb, IIc, IV, and VI are prominently expressed, whereas in astrocytes, Bdnf transcript containing exon VI is preferentially expressed, suggesting a specific regulation of Bdnf expression at the cellular level. Secondly, we confirmed the repressive role of Mecp2 only on the expression of Bdnf VI in neurons. Our data suggested that the truncated Mecp2 protein maintains its function on Bdnf expression regulation in neurons and in astrocytes. Interestingly, we observed that Bdnf transcripts (I and IXA), regulated by neural activity induced by bicuculline in Mecp2(308/y) neurons, were not affected by histone deacetylase inhibition. In contrast, Bdnf transcripts (IIb, IIc, and VI), regulated by histone deacetylation, were not affected by bicuculline treatment in wild-type and Mecp2(308/y) neurons. All these results reflect the complexity of regulation of Bdnf gene.

  19. Dickkopf1 Up-Regulation Induced by a High Concentration of Dexamethasone Promotes Rat Tendon Stem Cells to Differentiate Into Adipocytes

    Directory of Open Access Journals (Sweden)

    Wan Chen

    2015-11-01

    Full Text Available Background/Aims: Dexamethasone (Dex-induced spontaneous tendon rupture and decreased self-repair capability is very common in clinical practice. The metaplasia of adipose tissue in the ruptured tendon indicates that Dex may induce tendon stem cells (TSCs to differentiate into adipocytes, but the mechanism remains unclear. In the present study, we used in vitro methods to investigate the effects of Dex on rat TSC differentiation and the molecular mechanisms underlying this process. Methods: First, we used qPCR and Western blotting to detect the expression of the adipogenic differentiation markers aP2 and C/EBPα after treating the TSCs with Dex. Oil red staining was used to confirm that high concentration Dex promoted adipogenic differentiation of rat TSCs. Next, we used qPCR and Western blotting to detect the effect of a high concentration of dexamethasone on molecules related to the canonical WNT/β-catenin pathway in TSCs. Results: Treating rat TSCs with Dex promoted the synthesis of the inhibitory molecule dickkopf1 (DKK1 at the mRNA and protein levels. Western blotting results further showed that Dex downregulated the cellular signaling molecule phosphorylated glycogen synthase kinase-3β (P-GSK-3 β (ser9, upregulated P-GSK-3β (tyr216, and downregulated the pivotal signaling molecule β-catenin. Furthermore, DKK1 knockdown attenuated Dex-induced inhibition of the canonical WNT/β-catenin pathway and of the adipogenic differentiation of TSCs. Lithium chloride (LiCl, a GSK-3β inhibitor reduced Dex-induced inhibition of the classical WNT/β-catenin pathway in TSCs and of the differentiation of TSCs to adipocytes. Conclusion: In conclusion, by upregulating DKK1 expression, reducing the level of P-GSK-3β (ser9, and increasing the level of P-GSK-3β (tyr216, Dex causes the degradation of β-catenin, the central molecule of the classical WNT pathway, thereby inducing rat TSCs to differentiate into adipocytes.

  20. v-erbA overexpression is required to extinguish c-erbA function in erythroid cell differentiation and regulation of the erbA target gene CAII

    DEFF Research Database (Denmark)

    Disela, C; Glineur, C; Bugge, T

    1991-01-01

    The v-erbA oncoprotein represents a retrovirus-transduced oncogenic version of the thyroid hormone (T3/T4) receptor c-erbA (type alpha). It contributes to virus-induced erythroleukemia by efficiently arresting differentiation of red cell progenitors and by suppressing transcription of erythrocyte...... of this CAII reporter construct could only be suppressed by very high amounts of v-erbA. Our results suggest that overexpression of v-erbA is required for its function as an oncoprotein....

  1. Erk1 positively regulates osteoclast differentiation and bone resorptive activity.

    Directory of Open Access Journals (Sweden)

    Yongzheng He

    Full Text Available The extracellular signal-regulated kinases (ERK1 and 2 are widely-expressed and they modulate proliferation, survival, differentiation, and protein synthesis in multiple cell lineages. Altered ERK1/2 signaling is found in several genetic diseases with skeletal phenotypes, including Noonan syndrome, Neurofibromatosis type 1, and Cardio-facio-cutaneous syndrome, suggesting that MEK-ERK signals regulate human skeletal development. Here, we examine the consequence of Erk1 and Erk2 disruption in multiple functions of osteoclasts, specialized macrophage/monocyte lineage-derived cells that resorb bone. We demonstrate that Erk1 positively regulates osteoclast development and bone resorptive activity, as genetic disruption of Erk1 reduced osteoclast progenitor cell numbers, compromised pit formation, and diminished M-CSF-mediated adhesion and migration. Moreover, WT mice reconstituted long-term with Erk1(-/- bone marrow mononuclear cells (BMMNCs demonstrated increased bone mineral density as compared to recipients transplanted with WT and Erk2(-/- BMMNCs, implicating marrow autonomous, Erk1-dependent osteoclast function. These data demonstrate Erk1 plays an important role in osteoclast functions while providing rationale for the development of Erk1-specific inhibitors for experimental investigation and/or therapeutic modulation of aberrant osteoclast function.

  2. Regulating Chondrogenesis of Human Mesenchymal Stromal Cells with a Retinoic Acid Receptor-Beta Inhibitor: Differential Sensitivity of Chondral Versus Osteochondral Development

    Directory of Open Access Journals (Sweden)

    Solvig Diederichs

    2014-05-01

    Full Text Available Aim: Main objective was to investigate whether the synthetic retinoic acid receptor (RAR-β antagonist LE135 is able to drive in vitro chondrogenesis of human mesenchymal stromal cells (MSCs or improve differentiation by suppressing hypertrophic chondrocyte development. Methods: Chondrogenesis of human bone marrow and adipose tissue-derived MSCs was induced in micromass pellet culture for six weeks. Effects of LE135 alone and in combinatorial treatment with TGF-β on deposition of cartilaginous matrix including collagen type II and glycosaminoglycans, on deposition of non-hyaline cartilage collagens type I and X, and on hypertrophy markers including alkaline phosphatase (ALP, indian hedghehog (IHH and matrix metalloproteinase (MMP-13 were assessed. Results: LE135 was no inducer of chondrogenesis and failed to stimulate deposition of collagen type II and glycosaminoglycans. Moreover, addition of LE135 to TGF-β-treated pellets inhibited cartilaginous matrix deposition and gene expression of COL2A1. In contrast, non-hyaline cartilage collagens were less sensitive to LE135 and hypertrophy markers remained unaffected. Conclusion: This demonstrates a differential sensitivity of chondral versus endochondral differentiation pathways to RARβ signaling; however, opposite to the desired direction. The relevance of trans-activating versus trans-repressing RAR signaling, including effects on activator protein (AP-1 is discussed and implications for overcoming current limits of hMSC chondrogenesis are considered.

  3. Regulating chondrogenesis of human mesenchymal stromal cells with a retinoic Acid receptor-Beta inhibitor: differential sensitivity of chondral versus osteochondral development.

    Science.gov (United States)

    Diederichs, Solvig; Zachert, Kerstin; Raiss, Patric; Richter, Wiltrud

    2014-01-01

    Main objective was to investigate whether the synthetic retinoic acid receptor (RAR)-β antagonist LE135 is able to drive in vitro chondrogenesis of human mesenchymal stromal cells (MSCs) or improve differentiation by suppressing hypertrophic chondrocyte development. Chondrogenesis of human bone marrow and adipose tissue-derived MSCs was induced in micromass pellet culture for six weeks. Effects of LE135 alone and in combinatorial treatment with TGF-β on deposition of cartilaginous matrix including collagen type II and glycosaminoglycans, on deposition of non-hyaline cartilage collagens type I and X, and on hypertrophy markers including alkaline phosphatase (ALP), indian hedghehog (IHH) and matrix metalloproteinase (MMP)-13 were assessed. LE135 was no inducer of chondrogenesis and failed to stimulate deposition of collagen type II and glycosaminoglycans. Moreover, addition of LE135 to TGF-β-treated pellets inhibited cartilaginous matrix deposition and gene expression of COL2A1. In contrast, non-hyaline cartilage collagens were less sensitive to LE135 and hypertrophy markers remained unaffected. This demonstrates a differential sensitivity of chondral versus endochondral differentiation pathways to RARβ signaling; however, opposite to the desired direction. The relevance of trans-activating versus trans-repressing RAR signaling, including effects on activator protein (AP)-1 is discussed and implications for overcoming current limits of hMSC chondrogenesis are considered. © 2014 S. Karger AG, Basel.

  4. SIRT3/SOD2 maintains osteoblast differentiation and bone formation by regulating mitochondrial stress

    OpenAIRE

    Gao, Jing; Feng, Zhihui; Wang, Xueqiang; Zeng, Mengqi; Liu, Jing; Han, Shujun; Xu, Jie; Chen, Lei; Cao, Ke; Long, Jiangang; Li, Zongfang; Shen, Weili; Liu, Jiankang

    2017-01-01

    Recent studies have revealed robust metabolic changes during cell differentiation. Mitochondria, the organelles where many vital metabolic reactions occur, may play an important role. Here, we report the involvement of SIRT3-regulated mitochondrial stress in osteoblast differentiation and bone formation. In both the osteoblast cell line MC3T3-E1 and primary calvarial osteoblasts, robust mitochondrial biogenesis and supercomplex formation were observed during differentiation, accompanied by in...

  5. REGULATION OF TLR/RLR GENE ACTIVITY AND SYNTHESIS OF CYTOKINES DURING PHORBOL MYRISTATE ACETATE (PMA-INDUCED DIFFERENTIATION OF THP-1 MONOCYTES INTO MACROPHAGE-LIKE CELLS

    Directory of Open Access Journals (Sweden)

    T. M. Sokolova

    2017-01-01

    Full Text Available The levels of TLR/RLR gene expression and production of some cytokines were studied in monocytic THP-1 cell line during its differentiation to mature macrophage-like forms induced by phorbol 12-myristate 13-acetate (PMA treatment for 1 and 5 days in vitro. For the first time, we have shown high induction levels for the genes that encode signaling immune receptors and transcription factors in response to PMA, as well as inhibitory effects of TLR3, TLR7/TLR8, TLR9-agonists in mature macrophages. The PMAactivated THP-1 macrophage-like cells secreted large quantitities of inflammatory IL-1β and TNFα cytokines into culture medium.

  6. Novel function of the retinoblastoma protein in fat: regulation of white versus brown adipocyte differentiation

    DEFF Research Database (Denmark)

    Hansen, Jacob B; te Riele, Hein; Kristiansen, Karsten

    2004-01-01

    the major energy store and brown adipocytes being potent energy-dissipaters through thermogenesis. Yet, little is known about factors differentially regulating the formation of white and brown fat cells. Members of the retinoblastoma protein family (pRB, p107, p130) have been implicated in the regulation...... of adipocyte differentiation, and expression and phosphorylation of the three retinoblastoma family proteins oscillate in a characteristic manner during differentiation of the white preadipocyte cell line 3T3-L1. We have recently demonstrated a surprising function of the retinoblastoma protein...... in the regulation of white versus brown adipocyte differentiation in vitro and possibly in vivo. Here we summarize the current knowledge on the retinoblastoma protein in fat cells, with particular emphasis on its potential role in adipocyte lineage commitment and differentiation....

  7. Differentiation of stem cells upon deprivation of exogenous FGF2

    DEFF Research Database (Denmark)

    Kjartansdóttir, Kristín Rós; Gabrielsen, Anette; Reda, Ahmed

    2012-01-01

    Establishing a model for in vitro differentiation of human embryonic stem cells (hESCs) towards the germ cell lineage could be used to identify molecular mechanisms behind germ cell differentiation that may help in understanding human infertility. Here, we evaluate whether a lack of exogenous...... fibroblast growth factor 2 (FGF2) is supporting spontaneous differentiation of hESCs cultured on human foreskin fibroblast (hFF) monolayers towards germ cell lineage. Additionally to depriving the hESCs of exogenous FGF2, cells were stimulated with all-trans retinoic acid (ATRA). To get a more comprehensive...... impression on effects of removal of FGF2 and stimulation with ATRA, we combined the results of three cell lines for each experimental setting. When combining gene expression profiles of three cell lines for 96 genes, only 6 genes showed a significant up-regulation in all cell lines, when no FGF2 was added...

  8. RAGE, receptor of advanced glycation endoproducts, negatively regulates chondrocytes differentiation.

    Directory of Open Access Journals (Sweden)

    Tatsuya Kosaka

    Full Text Available RAGE, receptor for advanced glycation endoproducts (AGE, has been characterized as an activator of osteoclastgenesis. However, whether RAGE directly regulates chondrocyte proliferation and differentiation is unclear. Here, we show that RAGE has an inhibitory role in chondrocyte differentiation. RAGE expression was observed in chondrocytes from the prehypertrophic to hypertrophic regions. In cultured cells, overexpression of RAGE or dominant-negative-RAGE (DN-RAGE demonstrated that RAGE inhibited cartilaginous matrix production, while DN-RAGE promoted production. Additionally, RAGE regulated Ihh and Col10a1 negatively but upregulated PTHrP receptor. Ihh promoter analysis and real-time PCR analysis suggested that downregulation of Cdxs was the key for RAGE-induced inhibition of chondrocyte differentiation. Overexpression of the NF-κB inhibitor I-κB-SR inhibited RAGE-induced NF-κB activation, but did not influence inhibition of cartilaginous matrix production by RAGE. The inhibitory action of RAGE was restored by the Rho family GTPases inhibitor Toxin B. Furthermore, inhibitory action on Ihh, Col10a1 and Cdxs was reproduced by constitutively active forms, L63RhoA, L61Rac, and L61Cdc42, but not by I-κB-SR. Cdx1 induced Ihh and Col10a1 expressions and directly interacted with Ihh promoter. Retinoic acid (RA partially rescued the inhibitory action of RAGE. These data combined suggests that RAGE negatively regulates chondrocyte differentiation at the prehypertrophic stage by modulating NF-κB-independent and Rho family GTPases-dependent mechanisms.

  9. In vitro germ cell differentiation from cynomolgus monkey embryonic stem cells.

    Directory of Open Access Journals (Sweden)

    Kaori Yamauchi

    Full Text Available BACKGROUND: Mouse embryonic stem (ES cells can differentiate into female and male germ cells in vitro. Primate ES cells can also differentiate into immature germ cells in vitro. However, little is known about the differentiation markers and culture conditions for in vitro