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Sample records for area regulates cellular

  1. Glycosylation regulates prestin cellular activity.

    Science.gov (United States)

    Rajagopalan, Lavanya; Organ-Darling, Louise E; Liu, Haiying; Davidson, Amy L; Raphael, Robert M; Brownell, William E; Pereira, Fred A

    2010-03-01

    Glycosylation is a common post-translational modification of proteins and is implicated in a variety of cellular functions including protein folding, degradation, sorting and trafficking, and membrane protein recycling. The membrane protein prestin is an essential component of the membrane-based motor driving electromotility changes (electromotility) in the outer hair cell (OHC), a central process in auditory transduction. Prestin was earlier identified to possess two N-glycosylation sites (N163, N166) that, when mutated, marginally affect prestin nonlinear capacitance (NLC) function in cultured cells. Here, we show that the double mutant prestin(NN163/166AA) is not glycosylated and shows the expected NLC properties in the untreated and cholesterol-depleted HEK 293 cell model. In addition, unlike WT prestin that readily forms oligomers, prestin(NN163/166AA) is enriched as monomers and more mobile in the plasma membrane, suggesting that oligomerization of prestin is dependent on glycosylation but is not essential for the generation of NLC in HEK 293 cells. However, in the presence of increased membrane cholesterol, unlike the hyperpolarizing shift in NLC seen with WT prestin, cells expressing prestin(NN163/166AA) exhibit a linear capacitance function. In an attempt to explain this finding, we discovered that both WT prestin and prestin(NN163/166AA) participate in cholesterol-dependent cellular trafficking. In contrast to WT prestin, prestin(NN163/166AA) shows a significant cholesterol-dependent decrease in cell-surface expression, which may explain the loss of NLC function. Based on our observations, we conclude that glycosylation regulates self-association and cellular trafficking of prestin(NN163/166AA). These observations are the first to implicate a regulatory role for cellular trafficking and sorting in prestin function. We speculate that the cholesterol regulation of prestin occurs through localization to and internalization from membrane microdomains by

  2. Regulation of Cellular Tension in Adherent Cells

    Science.gov (United States)

    Oakes, Patrick

    2013-03-01

    Cells generate stress on their surrounding extracellular matrix (ECM) via myosin II motor generated forces which are transmitted through the actin cytoskeleton. The mechanisms in the cell which regulate the magnitude and spatial distribution of these stresses, however, remain unknown. Consistent with previous reports, we find that the total magnitude of traction force exerted on the ECM scales with cell size. Such scaling is observed across numerous cell types and reflects an inherent cellular tension determined by the level of myosin II activity. Surprisingly, while stiffness modulates the cellular spread area, we find this scaling relationship to be independent of ECM stiffness. To identify the biophysical mechanisms regulating the generation of tension, we utilize micro-patterning to isolate cell spread area from cell geometry and to spatially control the distribution of stress on the ECM. We find that traction stress magnitude is dependent on the local curvature of the cell. Changes in cell geometry result in a redistribution of local stresses, but little change in the total stress applied to the ECM. Finally, for a constant geometry, we find that both the total stress and the average stress exerted on the ECM increase with cell area. Together these data suggest that the cell can be modeled as a uniformly contracting mesh, where the magnitude of tension is regulated by the cell spread area, and the distribution of tension is regulated by local geometry.

  3. Empirical multiscale networks of cellular regulation.

    Directory of Open Access Journals (Sweden)

    Benjamin de Bivort

    2007-10-01

    Full Text Available Grouping genes by similarity of expression across multiple cellular conditions enables the identification of cellular modules. The known functions of genes enable the characterization of the aggregate biological functions of these modules. In this paper, we use a high-throughput approach to identify the effective mutual regulatory interactions between modules composed of mouse genes from the Alliance for Cell Signaling (AfCS murine B-lymphocyte database which tracks the response of approximately 15,000 genes following chemokine perturbation. This analysis reveals principles of cellular organization that we discuss along four conceptual axes. (1 Regulatory implications: the derived collection of influences between any two modules quantifies intuitive as well as unexpected regulatory interactions. (2 Behavior across scales: trends across global networks of varying resolution (composed of various numbers of modules reveal principles of assembly of high-level behaviors from smaller components. (3 Temporal behavior: tracking the mutual module influences over different time intervals provides features of regulation dynamics such as duration, persistence, and periodicity. (4 Gene Ontology correspondence: the association of modules to known biological roles of individual genes describes the organization of functions within coexpressed modules of various sizes. We present key specific results in each of these four areas, as well as derive general principles of cellular organization. At the coarsest scale, the entire transcriptional network contains five divisions: two divisions devoted to ATP production/biosynthesis and DNA replication that activate all other divisions, an "extracellular interaction" division that represses all other divisions, and two divisions (proliferation/differentiation and membrane infrastructure that activate and repress other divisions in specific ways consistent with cell cycle control.

  4. Lymphatic Regulation of Cellular Trafficking

    Science.gov (United States)

    Jackson, David G.

    2016-01-01

    Lymphatic vessels play vital roles in immune surveillance and immune regulation by conveying antigen loaded dendritic cells, memory T cells, macrophages and neutrophils from the peripheral tissues to draining lymph nodes where they initiate as well as modify immune responses. Until relatively recently however, there was little understanding of how entry and migration through lymphatic vessels is organized or the specific molecular mechanisms that might be involved. Within the last decade, the situation has been transformed by an explosion of knowledge generated largely through the application of microscopic imaging, transgenic animals, specific markers and function blocking mAbs that is beginning to provide a rational conceptual framework. This article provides a critical review of the recent literature, highlighting seminal discoveries that have revealed the fascinating ultrastructure of leucocyte entry sites in lymphatic vessels, as well as generating controversies over the involvement of integrin adhesion, chemotactic and haptotactic mechanisms in DC entry under normal and inflamed conditions. It also discusses the major changes in lymphatic architecture that occur during inflammation and the different modes of leucocyte entry and trafficking within inflamed lymphatic vessels, as well as presenting a timely update on the likely role of hyaluronan and the major lymphatic endothelial hyaluronan receptor LYVE-1 in leucocyte transit.

  5. Cellular regulation of the dopamine transporter

    DEFF Research Database (Denmark)

    Eriksen, Jacob

    2010-01-01

    The dopamine transporter (DAT) mediates reuptake of dopamine from the synaptic cleft and is a target for widely abused psychostimulants such as cocaine and amphetamine. Nonetheless, little is known about the cellular distribution and trafficking of natively expressed DAT. DAT and its trafficking...... in heterologous cells and in cultured DA neurons. DAT has been shown to be regulated by the dopamine D2 receptor (D2R), the primary target foranti-psychotics, through a direct interaction. D2R is among other places expressed as an autoreceptor in DA neurons. Transient over-expression of DAT with D2R in HEK293...

  6. Rethinking the regulation of cellular metabolism.

    Science.gov (United States)

    Thompson, C B

    2011-01-01

    Most biologists working today have not considered the problem of how signal transduction events, which commit cells to energetically demanding processes such as growth and division, are connected to cellular metabolism. The primary reason for this is that we have believed for the last 30 or more years that the metabolism of cells is a homeostatic, self-regulating process that does not depend on any extracellular input. The traditional view is that a mammalian cell decides to take up nutrients whenever its bioenergetic and synthetic reserves are depleted. However, a considerable body of evidence now exists that challenges the notion that the nutrient uptake and metabolism of metazoan cells are cell-autonomous.

  7. 47 CFR 22.911 - Cellular geographic service area.

    Science.gov (United States)

    2010-10-01

    ... PUBLIC MOBILE SERVICES Cellular Radiotelephone Service § 22.911 Cellular geographic service area. The... Watts (2) The distance from a cell transmitting antenna located in the Gulf of Mexico Service Area (GMSA... for unserved area applications proposing a cell with an ERP not exceeding 10 Watts, the value for...

  8. Activation and Regulation of Cellular Eicosanoid Biosynthesis

    Directory of Open Access Journals (Sweden)

    Thomas G. Brock

    2007-01-01

    Full Text Available There is a growing appreciation for the wide variety of physiological responses that are regulated by lipid messengers. One particular group of lipid messengers, the eicosanoids, plays a central role in regulating immune and inflammatory responses in a receptor-mediated fashion. These mediators are related in that they are all derived from one polyunsaturated fatty acid, arachidonic acid. However, the various eicosanoids are synthesized by a wide variety of cell types by distinct enzymatic pathways, and have diverse roles in immunity and inflammation. In this review, the major pathways involved in the synthesis of eicosanoids, as well as key points of regulation, are presented.

  9. Cellular regulation of the dopamine transporter

    DEFF Research Database (Denmark)

    Eriksen, Jacob

    2010-01-01

    -membrane spanning protein Tac, thereby creating an extracellular antibody epitope. Upon expression in HEK293 cells this TacDAT fusion protein displayed functional properties similar to the wild type transporter. In an ELISA based internalization assay, TacDAT intracellular accumulation was increased by inhibitors......The dopamine transporter (DAT) mediates reuptake of dopamine from the synaptic cleft and is a target for widely abused psychostimulants such as cocaine and amphetamine. Nonetheless, little is known about the cellular distribution and trafficking of natively expressed DAT. DAT and its trafficking...... to natively expressed transporter, DAT was visualized directly in cultured DA neurons using the fluorescent cocaine analog JHC 1-64. These data showed pronounced colocalization upon constitutive internalization with Lysotracker, a late endosomal/lysosomal marker; however only little cololization was observed...

  10. Regulation of ARE-mRNA Stability by Cellular Signaling

    DEFF Research Database (Denmark)

    Damgaard, Christian Kroun; Lykke-Andersen, Jens

    2013-01-01

    but as a response to different cellular cues they can become either stabilized, allowing expression of a given gene, or further destabilized to silence their expression. These tightly regulated mRNAs include many that encode growth factors, proto-oncogenes, cytokines, and cell cycle regulators. Failure to properly...

  11. From syncitium to regulated pump: a cardiac muscle cellular update.

    Science.gov (United States)

    Korzick, Donna H

    2011-03-01

    The primary purpose of this article is to present a basic overview of some key teaching concepts that should be considered for inclusion in an six- to eight-lecture introductory block on the regulation of cardiac performance for graduate students. Within the context of cardiac excitation-contraction coupling, this review incorporates information on Ca(2+) microdomains and local control theory, with particular emphasis on the role of Ca(2+) sparks as a key regulatory component of ventricular myocyte contraction dynamics. Recent information pertaining to local Ca(2+) cycling in sinoatrial nodal cells (SANCs) as a mechanism underlying cardiac automaticity is also presented as part of the recently described coupled-clock pacemaker system. The details of this regulation are emerging; however, the notion that the sequestration and release of Ca(2+) from internal stores in SANCs (similar to that observed in ventricular myocytes) regulates the rhythmic excitation of the heart (i.e., membrane ion channels) is an important advancement in this area. The regulatory role of cardiac adrenergic receptors on cardiac rate and function is also included, and fundamental concepts related to intracellular signaling are discussed. An important point of emphasis is that whole organ cardiac dynamics can be traced back to cellular events regulating intracellular Ca(2+) homeostasis and, as such, provides an important conceptual framework from which students can begin to think about whole organ physiology in health and disease. Greater synchrony of Ca(2+)-regulatory mechanisms between ventricular and pacemaker cells should enhance student comprehension of complex regulatory phenomenon in cardiac muscle.

  12. Piezo proteins: regulators of mechanosensation and other cellular processes.

    Science.gov (United States)

    Bagriantsev, Sviatoslav N; Gracheva, Elena O; Gallagher, Patrick G

    2014-11-14

    Piezo proteins have recently been identified as ion channels mediating mechanosensory transduction in mammalian cells. Characterization of these channels has yielded important insights into mechanisms of somatosensation, as well as other mechano-associated biologic processes such as sensing of shear stress, particularly in the vasculature, and regulation of urine flow and bladder distention. Other roles for Piezo proteins have emerged, some unexpected, including participation in cellular development, volume regulation, cellular migration, proliferation, and elongation. Mutations in human Piezo proteins have been associated with a variety of disorders including hereditary xerocytosis and several syndromes with muscular contracture as a prominent feature.

  13. 10 CFR 850.26 - Regulated areas.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false Regulated areas. 850.26 Section 850.26 Energy DEPARTMENT... Regulated areas. (a) If airborne concentrations of beryllium in areas in DOE facilities are measured at or above the action level, the responsible employer must establish regulated areas for those areas. (b)...

  14. Osmosensory mechanisms in cellular and systemic volume regulation

    DEFF Research Database (Denmark)

    Pedersen, Stine Helene Falsig; Kapus, András; Hoffmann, Else K

    2011-01-01

    Perturbations of cellular and systemic osmolarity severely challenge the function of all organisms and are consequently regulated very tightly. Here we outline current evidence on how cells sense volume perturbations, with particular focus on mechanisms relevant to the kidneys and to extracellular...

  15. Cellular regulation of the structure and function of aortic valves

    Directory of Open Access Journals (Sweden)

    Ismail El-Hamamsy

    2010-01-01

    Full Text Available The aortic valve was long considered a passive structure that opens and closes in response to changes in transvalvular pressure. Recent evidence suggests that the aortic valve performs highly sophisticated functions as a result of its unique microscopic structure. These functions allow it to adapt to its hemodynamic and mechanical environment. Understanding the cellular and molecular mechanisms involved in normal valve physiology is essential to elucidate the mechanisms behind valve disease. We here review the structure and developmental biology of aortic valves; we examine the role of its cellular parts in regulating its function and describe potential pathophysiological and clinical implications.

  16. Area Green Efficiency (AGE) of Two Tier Heterogeneous Cellular Networks

    KAUST Repository

    Tabassum, Hina

    2012-10-03

    Small cell networks are becoming standard part of the future heterogeneous networks. In this paper, we consider a two tier heterogeneous network which promises energy savings by integrating the femto and macro cellular networks and thereby reducing CO2 emissions, operational and capital expenditures (OPEX and CAPEX) whilst enhancing the area spectral efficiency (ASE) of the network. In this context, we define a performance metric which characterize the aggregate energy savings per unit macrocell area and is referred to as area green efficiency (AGE) of the two tier heterogeneous network where the femto base stations are arranged around the edge of the reference macrocell such that the configuration is referred to as femto-on-edge (FOE). The mobile users in macro and femto cellular networks are transmitting with the adaptive power while maintaining the desired link quality such that the energy aware FOE configuration mandates to (i) save energy, and (ii) reduce the co-channel interference. We present a mathematical analysis to incorporate the uplink power control mechanism adopted by the mobile users and calibrate the uplink ASE and AGE of the energy aware FOE configuration. Next, we derive analytical expressions to compute the bounds on the uplink ASE of energy aware FOE configuration and demonstrate that the derived bounds are useful in evaluating the ASE under worst and best case interference scenarios. Simulation results are produced to demonstrate the ASE and AGE improvements in comparison to macro-only and macro-femto configuration with uniformly distributed femtocells.

  17. Daily magnesium fluxes regulate cellular timekeeping and energy balance.

    Science.gov (United States)

    Feeney, Kevin A; Hansen, Louise L; Putker, Marrit; Olivares-Yañez, Consuelo; Day, Jason; Eades, Lorna J; Larrondo, Luis F; Hoyle, Nathaniel P; O'Neill, John S; van Ooijen, Gerben

    2016-04-21

    Circadian clocks are fundamental to the biology of most eukaryotes, coordinating behaviour and physiology to resonate with the environmental cycle of day and night through complex networks of clock-controlled genes. A fundamental knowledge gap exists, however, between circadian gene expression cycles and the biochemical mechanisms that ultimately facilitate circadian regulation of cell biology. Here we report circadian rhythms in the intracellular concentration of magnesium ions, [Mg(2+)]i, which act as a cell-autonomous timekeeping component to determine key clock properties both in a human cell line and in a unicellular alga that diverged from each other more than 1 billion years ago. Given the essential role of Mg(2+) as a cofactor for ATP, a functional consequence of [Mg(2+)]i oscillations is dynamic regulation of cellular energy expenditure over the daily cycle. Mechanistically, we find that these rhythms provide bilateral feedback linking rhythmic metabolism to clock-controlled gene expression. The global regulation of nucleotide triphosphate turnover by intracellular Mg(2+) availability has potential to impact upon many of the cell's more than 600 MgATP-dependent enzymes and every cellular system where MgNTP hydrolysis becomes rate limiting. Indeed, we find that circadian control of translation by mTOR is regulated through [Mg(2+)]i oscillations. It will now be important to identify which additional biological processes are subject to this form of regulation in tissues of multicellular organisms such as plants and humans, in the context of health and disease.

  18. Proteoform-Specific Insights into Cellular Proteome Regulation.

    Science.gov (United States)

    Norris, Emma L; Headlam, Madeleine J; Dave, Keyur A; Smith, David D; Bukreyev, Alexander; Singh, Toshna; Jayakody, Buddhika A; Chappell, Keith J; Collins, Peter L; Gorman, Jeffrey J

    2016-10-01

    Knowledge regarding compositions of proteomes at the proteoform level enhances insights into cellular phenotypes. A strategy is described herein for discovery of proteoform-specific information about cellular proteomes. This strategy involved analysis of data obtained by bottom-up mass spectrometry of multiple protein OGE separations on a fraction by fraction basis. The strategy was exemplified using five matched sets of lysates of uninfected and human respiratory syncytial virus-infected A549 cells. Template matching demonstrated that 67.3% of 10475 protein profiles identified focused to narrow pI windows indicative of efficacious focusing. Furthermore, correlation between experimental and theoretical pI gradients indicated reproducible focusing. Based on these observations a proteoform profiling strategy was developed to identify proteoforms, detect proteoform diversity and discover potential proteoform regulation. One component of this strategy involved examination of the focusing profiles for protein groups. A novel concordance analysis facilitated differentiation between proteoforms, including proteoforms generated by alternate splicing and proteolysis. Evaluation of focusing profiles and concordance analysis were applicable to cells from a single and/or multiple biological states. Statistical analyses identified proteoform variation between biological states. Regulation relevant to cellular responses to human respiratory syncytial virus was revealed. Western blotting and Protomap analyses validated the proteoform regulation. Discovery of STAT1, WARS, MX1, and HSPB1 proteoform regulation by human respiratory syncytial virus highlighted the impact of the profiling strategy. Novel truncated proteoforms of MX1 were identified in infected cells and phosphorylation driven regulation of HSPB1 proteoforms was correlated with infection. The proteoform profiling strategy is generally applicable to investigating interactions between viruses and host cells and the

  19. Global self-regulation of the cellular metabolic structure.

    Directory of Open Access Journals (Sweden)

    Ildefonso M De la Fuente

    Full Text Available BACKGROUND: Different studies have shown that cellular enzymatic activities are able to self-organize spontaneously, forming a metabolic core of reactive processes that remain active under different growth conditions while the rest of the molecular catalytic reactions exhibit structural plasticity. This global cellular metabolic structure appears to be an intrinsic characteristic common to all cellular organisms. Recent work performed with dissipative metabolic networks has shown that the fundamental element for the spontaneous emergence of this global self-organized enzymatic structure could be the number of catalytic elements in the metabolic networks. METHODOLOGY/PRINCIPAL FINDINGS: In order to investigate the factors that may affect the catalytic dynamics under a global metabolic structure characterized by the presence of metabolic cores we have studied different transitions in catalytic patterns belonging to a dissipative metabolic network. The data were analyzed using non-linear dynamics tools: power spectra, reconstructed attractors, long-term correlations, maximum Lyapunov exponent and Approximate Entropy; and we have found the emergence of self-regulation phenomena during the transitions in the metabolic activities. CONCLUSIONS/SIGNIFICANCE: The analysis has also shown that the chaotic numerical series analyzed correspond to the fractional Brownian motion and they exhibit long-term correlations and low Approximate Entropy indicating a high level of predictability and information during the self-regulation of the metabolic transitions. The results illustrate some aspects of the mechanisms behind the emergence of the metabolic self-regulation processes, which may constitute an important property of the global structure of the cellular metabolism.

  20. Regulation and quantification of cellular mitochondrial morphology and content.

    Science.gov (United States)

    Tronstad, Karl J; Nooteboom, Marco; Nilsson, Linn I H; Nikolaisen, Julie; Sokolewicz, Maciek; Grefte, Sander; Pettersen, Ina K N; Dyrstad, Sissel; Hoel, Fredrik; Willems, Peter H G M; Koopman, Werner J H

    2014-01-01

    Mitochondria play a key role in signal transduction, redox homeostasis and cell survival, which extends far beyond their classical functioning in ATP production and energy metabolism. In living cells, mitochondrial content ("mitochondrial mass") depends on the cell-controlled balance between mitochondrial biogenesis and degradation. These processes are intricately linked to changes in net mitochondrial morphology and spatiotemporal positioning ("mitochondrial dynamics"), which are governed by mitochondrial fusion, fission and motility. It is becoming increasingly clear that mitochondrial mass and dynamics, as well as its ultrastructure and volume, are mechanistically linked to mitochondrial function and the cell. This means that proper quantification of mitochondrial morphology and content is of prime importance in understanding mitochondrial and cellular physiology in health and disease. This review first presents how cellular mitochondrial content is regulated at the level of mitochondrial biogenesis, degradation and dynamics. Next we discuss how mitochondrial dynamics and content can be analyzed with a special emphasis on quantitative live-cell microscopy strategies.

  1. Complement-Mediated Regulation of Metabolism and Basic Cellular Processes.

    Science.gov (United States)

    Hess, Christoph; Kemper, Claudia

    2016-08-16

    Complement is well appreciated as a critical arm of innate immunity. It is required for the removal of invading pathogens and works by directly destroying them through the activation of innate and adaptive immune cells. However, complement activation and function is not confined to the extracellular space but also occurs within cells. Recent work indicates that complement activation regulates key metabolic pathways and thus can impact fundamental cellular processes, such as survival, proliferation, and autophagy. Newly identified functions of complement include a key role in shaping metabolic reprogramming, which underlies T cell effector differentiation, and a role as a nexus for interactions with other effector systems, in particular the inflammasome and Notch transcription-factor networks. This review focuses on the contributions of complement to basic processes of the cell, in particular the integration of complement with cellular metabolism and the potential implications in infection and other disease settings.

  2. Redox regulation of SIRT1 in inflammation and cellular senescence.

    Science.gov (United States)

    Hwang, Jae-woong; Yao, Hongwei; Caito, Samuel; Sundar, Isaac K; Rahman, Irfan

    2013-08-01

    Sirtuin 1 (SIRT1) regulates inflammation, aging (life span and health span), calorie restriction/energetics, mitochondrial biogenesis, stress resistance, cellular senescence, endothelial functions, apoptosis/autophagy, and circadian rhythms through deacetylation of transcription factors and histones. SIRT1 level and activity are decreased in chronic inflammatory conditions and aging, in which oxidative stress occurs. SIRT1 is regulated by a NAD(+)-dependent DNA repair enzyme, poly(ADP-ribose) polymerase-1 (PARP1), and subsequent NAD(+) depletion by oxidative stress may have consequent effects on inflammatory and stress responses as well as cellular senescence. SIRT1 has been shown to undergo covalent oxidative modifications by cigarette smoke-derived oxidants/aldehydes, leading to posttranslational modifications, inactivation, and protein degradation. Furthermore, oxidant/carbonyl stress-mediated reduction of SIRT1 leads to the loss of its control on acetylation of target proteins including p53, RelA/p65, and FOXO3, thereby enhancing the inflammatory, prosenescent, and apoptotic responses, as well as endothelial dysfunction. In this review, the mechanisms of cigarette smoke/oxidant-mediated redox posttranslational modifications of SIRT1 and its roles in PARP1 and NF-κB activation, and FOXO3 and eNOS regulation, as well as chromatin remodeling/histone modifications during inflammaging, are discussed. Furthermore, we have also discussed various novel ways to activate SIRT1 either directly or indirectly, which may have therapeutic potential in attenuating inflammation and premature senescence involved in chronic lung diseases.

  3. REDOX REGULATION OF SIRT1 IN INFLAMMATION AND CELLULAR SENESCENCE

    Science.gov (United States)

    Hwang, Jae-woong; Yao, Hongwei; Caito, Samuel; Sundar, Isaac K.; Rahman, Irfan

    2013-01-01

    Sirtuin1 (SIRT1) regulates inflammation, aging (lifespan and healthspan), calorie restriction/energetics, mitochondrial biogenesis, stress resistance, cellular senescence, endothelial functions, apoptosis/autophagy, and circadian rhythms through deacetylation of transcription factors and histones. SIRT1 level and activity are decreased in chronic inflammatory conditions and aging where oxidative stress occurs. SIRT1 is regulated by a NAD+-dependent DNA repair enzyme poly(ADP-ribose)-polymerase-1 (PARP-1), and subsequent NAD+ depletion by oxidative stresses may have consequent effects on inflammatory and stress responses as well as cellular senescence. SIRT1 has been shown to undergo covalent oxidative modifications by cigarette smoke-derived oxidants/aldehydes, leading to post-translational modifications, inactivation, and protein degradation. Furthermore, oxidant/carbonyl stress-mediated reduction of SIRT1 leads to the loss of its control on acetylation of target proteins including p53, RelA/p65 and FOXO3, thereby enhancing the inflammatory, pro-senescent and apoptotic responses, as well as endothelial dysfunction. In this review, the mechanisms of cigarette smoke/oxidant-mediated redox post-translational modifications of SIRT1 and its role in PARP1, NF-κB activation, FOXO3 and eNOS regulation, as well as chromatin remodeling/histone modifications during inflammaging are discussed. Furthermore, we also discussed various novel ways to activate SIRT1 either directly or indirectly, which may have therapeutic potential in attenuating inflammation and premature senescence involved in chronic lung diseases. PMID:23542362

  4. 46 CFR 197.535 - Regulated areas.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Regulated areas. 197.535 Section 197.535 Shipping COAST... GENERAL PROVISIONS Benzene § 197.535 Regulated areas. (a) Based on the employer's evaluation of the environmental monitoring, whenever the airborne concentration of benzene within an area exceeds or...

  5. H(2)S signaling in redox regulation of cellular functions.

    Science.gov (United States)

    Ju, Youngjun; Zhang, Weihua; Pei, Yanxi; Yang, Guangdong

    2013-01-01

    Hydrogen sulfide (H(2)S) is traditionally recognized as a toxic gas with a rotten-egg smell. In just the last few decades, H(2)S has been found to be one of a family of gasotransmitters, together with nitric oxide and carbon monoxide, and various physiologic effects of H(2)S have been reported. Among the most acknowledged molecular mechanisms for the cellular effects of H(2)S is the regulation of intracellular redox homeostasis and post-translational modification of proteins through S-sulfhydration. On the one side, H(2)S can promote an antioxidant effect and is cytoprotective; on the other side, H(2)S stimulates oxidative stress and is cytotoxic. This review summarizes our current knowledge of the antioxidant versus pro-oxidant effects of H(2)S in mammalian cells and describes the Janus-faced properties of this novel gasotransmitter. The redox regulation for the cellular effects of H(2)S through S-sulfhydration and the role of H(2)S in glutathione generation is also recapitulated. A better understanding of H(2)S-regualted redox homeostasis will pave the way for future design of novel pharmacological and therapeutic interventions for various diseases.

  6. Cellular Functions Regulated by Phosphorylation of EGFR on Tyr845

    Directory of Open Access Journals (Sweden)

    Ken-ichi Sato

    2013-05-01

    Full Text Available The Src gene product (Src and the epidermal growth factor receptor (EGFR are prototypes of oncogene products and function primarily as a cytoplasmic non-receptor tyrosine kinase and a transmembrane receptor tyrosine kinase, respectively. The identification of Src and EGFR, and the subsequent extensive investigations of these proteins have long provided cutting edge research in cancer and other molecular and cellular biological studies. In 1995, we reported that the human epidermoid carcinoma cells, A431, contain a small fraction of Src and EGFR in which these two kinase were in physical association with each other, and that Src phosphorylates EGFR on tyrosine 845 (Y845 in the Src-EGFR complex. Y845 of EGFR is located in the activation segment of the kinase domain, where many protein kinases contain kinase-activating autophosphorylation sites (e.g., cAMP-dependent protein kinase, Src family kinases, transmembrane receptor type tyrosine kinases or trans-phosphorylation sites (e.g., cyclin-dependent protein kinase, mitogen-activated protein kinase, Akt protein kinase. A number of studies have demonstrated that Y845 phosphorylation serves an important role in cancer as well as normal cells. Here we compile the experimental facts involving Src phosphorylation of EGFR on Y845, by which cell proliferation, cell cycle control, mitochondrial regulation of cell metabolism, gamete activation and other cellular functions are regulated. We also discuss the physiological relevance, as well as structural insights of the Y845 phosphorylation.

  7. MOF maintains transcriptional programs regulating cellular stress response.

    Science.gov (United States)

    Sheikh, B N; Bechtel-Walz, W; Lucci, J; Karpiuk, O; Hild, I; Hartleben, B; Vornweg, J; Helmstädter, M; Sahyoun, A H; Bhardwaj, V; Stehle, T; Diehl, S; Kretz, O; Voss, A K; Thomas, T; Manke, T; Huber, T B; Akhtar, A

    2016-05-01

    MOF (MYST1, KAT8) is the major H4K16 lysine acetyltransferase (KAT) in Drosophila and mammals and is essential for embryonic development. However, little is known regarding the role of MOF in specific cell lineages. Here we analyze the differential role of MOF in proliferating and terminally differentiated tissues at steady state and under stress conditions. In proliferating cells, MOF directly binds and maintains the expression of genes required for cell cycle progression. In contrast, MOF is dispensable for terminally differentiated, postmitotic glomerular podocytes under physiological conditions. However, in response to injury, MOF is absolutely critical for podocyte maintenance in vivo. Consistently, we detect defective nuclear, endoplasmic reticulum and Golgi structures, as well as presence of multivesicular bodies in vivo in podocytes lacking Mof following injury. Undertaking genome-wide expression analysis of podocytes, we uncover several MOF-regulated pathways required for stress response. We find that MOF, along with the members of the non-specific lethal but not the male-specific lethal complex, directly binds to genes encoding the lysosome, endocytosis and vacuole pathways, which are known regulators of podocyte maintenance. Thus, our work identifies MOF as a key regulator of cellular stress response in glomerular podocytes.

  8. Operating principles of tristable circuits regulating cellular differentiation

    Science.gov (United States)

    Jia, Dongya; Jolly, Mohit Kumar; Harrison, William; Boareto, Marcelo; Ben-Jacob, Eshel; Levine, Herbert

    2017-06-01

    Many cell-fate decisions during embryonic development are governed by a motif comprised of two transcription factors (TFs) A and B that mutually inhibit each other and may self-activate. This motif, called as a self-activating toggle switch (SATS), can typically have three stable states (phenotypes)—two corresponding to differentiated cell fates, each of which has a much higher level of one TF than the other—≤ft(A,~B\\right)=≤ft(1,~0\\right) or ≤ft(0,~1\\right) —and the third state corresponding to an ‘undecided’ stem-like state with similar levels of both A and B—≤ft(A,~B\\right)=≤ft(1/2,1/2\\right) . Furthermore, two or more SATSes can be coupled together in various topologies in different contexts, thereby affecting the coordination between multiple cellular decisions. However, two questions remain largely unanswered: (a) what governs the co-existence and relative stability of these three stable states? (b) What orchestrates the decision-making of coupled SATSes? Here, we first demonstrate that the co-existence and relative stability of the three stable states in an individual SATS can be governed by the relative strength of self-activation, external signals activating and/or inhibiting A and B, and mutual degradation between A and B. Simultaneously, we investigate the effects of these factors on the decision-making of two coupled SATSes. Our results offer novel understanding into the operating principles of individual and coupled tristable self-activating toggle switches (SATSes) regulating cellular differentiation and can yield insights into synthesizing three-way genetic circuits and understanding of cellular reprogramming.

  9. Budded membrane microdomains as regulators for cellular tension

    OpenAIRE

    Sens, Pierre; Turner, Matthew S.

    2005-01-01

    We propose a mechanism for mechanical regulation at the membrane of living cells, based on the exchange of membrane area between the cell membrane and a membrane reservoir. The reservoir is composed of invaginated membrane microdomains which are liable to flatten upon increase of membrane strain, effectively controlling membrane tension. We show that the domain shape transition is first order, allowing for coexistence between flat and invaginated domains. During coexistence, the membrane tens...

  10. Regulation of System xc− by Pharmacological Manipulation of Cellular Thiols

    Science.gov (United States)

    Albano, Rebecca; Raddatz, Nicholas J.; Hjelmhaug, Julie; Baker, David A.; Lobner, Doug

    2015-01-01

    The cystine/glutamate exchanger (system xc−) mediates the transport of cystine into the cell in exchange for glutamate. By releasing glutamate, system xc− can potentially cause excitotoxicity. However, through providing cystine to the cell, it regulates the levels of cellular glutathione (GSH), the main endogenous intracellular antioxidant, and may protect cells against oxidative stress. We tested two different compounds that deplete primary cortical cultures containing both neurons and astrocytes of intracellular GSH, L-buthionine-sulfoximine (L-BSO), and diethyl maleate (DEM). Both compounds caused significant concentration and time dependent decreases in intracellular GSH levels. However; DEM caused an increase in radiolabeled cystine uptake through system xc−, while unexpectedly BSO caused a decrease in uptake. The compounds caused similar low levels of neurotoxicity, while only BSO caused an increase in oxidative stress. The mechanism of GSH depletion by these two compounds is different, DEM directly conjugates to GSH, while BSO inhibits γ-glutamylcysteine synthetase, a key enzyme in GSH synthesis. As would be expected from these mechanisms of action, DEM caused a decrease in intracellular cysteine, while BSO increased cysteine levels. The results suggest that negative feedback by intracellular cysteine is an important regulator of system xc− in this culture system. PMID:25949770

  11. Regulation of System xc- by Pharmacological Manipulation of Cellular Thiols

    Directory of Open Access Journals (Sweden)

    Rebecca Albano

    2015-01-01

    Full Text Available The cystine/glutamate exchanger (system xc- mediates the transport of cystine into the cell in exchange for glutamate. By releasing glutamate, system xc- can potentially cause excitotoxicity. However, through providing cystine to the cell, it regulates the levels of cellular glutathione (GSH, the main endogenous intracellular antioxidant, and may protect cells against oxidative stress. We tested two different compounds that deplete primary cortical cultures containing both neurons and astrocytes of intracellular GSH, L-buthionine-sulfoximine (L-BSO, and diethyl maleate (DEM. Both compounds caused significant concentration and time dependent decreases in intracellular GSH levels. However; DEM caused an increase in radiolabeled cystine uptake through system xc-, while unexpectedly BSO caused a decrease in uptake. The compounds caused similar low levels of neurotoxicity, while only BSO caused an increase in oxidative stress. The mechanism of GSH depletion by these two compounds is different, DEM directly conjugates to GSH, while BSO inhibits γ-glutamylcysteine synthetase, a key enzyme in GSH synthesis. As would be expected from these mechanisms of action, DEM caused a decrease in intracellular cysteine, while BSO increased cysteine levels. The results suggest that negative feedback by intracellular cysteine is an important regulator of system xc- in this culture system.

  12. Cellular interactions regulate stem cell differentiation in tri-culture.

    Science.gov (United States)

    Wang, I-Ning E; Bogdanowicz, Danielle R; Mitroo, Siddarth; Shan, Jing; Kala, Sonam; Lu, Helen H

    2016-11-01

    Currently, the mechanism governing the regeneration of the soft tissue-to-bone interface, such as the transition between the anterior cruciate ligament (ACL) and bone, is not known. Focusing on the ACL-to-bone insertion, this study tests the novel hypothesis that interactions between cells from the ligament (fibroblasts) and bone (osteoblasts) initiate interface regeneration. Specifically, these heterotypic cell interactions direct the fibrochondrogenic differentiation of interface-relevant cell populations, defined here as ligament fibroblasts and bone marrow stromal cells (BMSC). The objective of this study is to examine the effects of heterotypic cellular interactions on BMSC or fibroblast growth and biosynthesis, as well as expression of fibrocartilage-relevant markers in tri-culture. The effects of cell-cell physical contact and paracrine interactions between fibroblasts and osteoblasts were also determined. It was found that, in tri-culture with fibroblasts and osteoblasts, BMSC exhibited greater fibrochondrogenic potential than ligament fibroblasts. The growth of BMSC decreased while proteoglycan production and TGF-β3 expression increased. Moreover, tri-culture regulated BMSC response via paracrine factors, and interestingly, fibroblast-osteoblast contact further promoted proteoglycan and TGF-β1 synthesis as well as induced SOX9 expression in BMSC. Collectively, the findings of this study suggest that fibroblast-osteoblast interactions play an important role in regulating the stem cell niche for fibrocartilage regeneration, and the mechanisms of these interactions are directed by paracrine factors and augmented with direct cell-cell contact.

  13. Regulation of System xc(-) by Pharmacological Manipulation of Cellular Thiols.

    Science.gov (United States)

    Albano, Rebecca; Raddatz, Nicholas J; Hjelmhaug, Julie; Baker, David A; Lobner, Doug

    2015-01-01

    The cystine/glutamate exchanger (system xc (-)) mediates the transport of cystine into the cell in exchange for glutamate. By releasing glutamate, system xc (-) can potentially cause excitotoxicity. However, through providing cystine to the cell, it regulates the levels of cellular glutathione (GSH), the main endogenous intracellular antioxidant, and may protect cells against oxidative stress. We tested two different compounds that deplete primary cortical cultures containing both neurons and astrocytes of intracellular GSH, L-buthionine-sulfoximine (L-BSO), and diethyl maleate (DEM). Both compounds caused significant concentration and time dependent decreases in intracellular GSH levels. However; DEM caused an increase in radiolabeled cystine uptake through system xc (-), while unexpectedly BSO caused a decrease in uptake. The compounds caused similar low levels of neurotoxicity, while only BSO caused an increase in oxidative stress. The mechanism of GSH depletion by these two compounds is different, DEM directly conjugates to GSH, while BSO inhibits γ-glutamylcysteine synthetase, a key enzyme in GSH synthesis. As would be expected from these mechanisms of action, DEM caused a decrease in intracellular cysteine, while BSO increased cysteine levels. The results suggest that negative feedback by intracellular cysteine is an important regulator of system xc (-) in this culture system.

  14. Cellular metabolism regulates contact sites between vacuoles and mitochondria

    NARCIS (Netherlands)

    Hönscher, Carina; Mari, Muriel; Auffarth, Kathrin; Bohnert, Maria; Griffith, Janice; Geerts, Willie; van der Laan, Martin; Cabrera, Margarita; Reggiori, Fulvio; Ungermann, Christian

    2014-01-01

    Emerging evidence suggests that contact sites between different organelles form central hubs in the coordination of cellular physiology. Although recent work has emphasized the crucial role of the endoplasmic reticulum in interorganellar crosstalk, the cooperative behavior of other organelles is

  15. 77 FR 15665 - Cellular Service, Including Changes in Licensing of Unserved Area; Interim Restrictions and...

    Science.gov (United States)

    2012-03-16

    ... for every Cellular Market Area (CMA) and corresponding channel block (Block A or Block B), in two... this document. FOR FURTHER INFORMATION CONTACT: Nina Shafran, Wireless Telecommunications Bureau... Proposed Rulemaking I. Introduction 1. Since its inception roughly 30 years ago, the Cellular Service...

  16. Cod avoidance by area regulations in Kattegat

    DEFF Research Database (Denmark)

    Eliasen, Søren Qvist

    2014-01-01

    presents two initiatives for cod avoidance in Kattegat; a fisher initiative sharing information about cod bycatch which could lead to real time closures in areas with high bycatch of juveniles, for vessels with low cod quota to avoid catch of all cod, and a Danish Swedish Government initiative of permanent......The article examines the experiences of two initiatives of cod avoidance by area regulations in the Kattegat in the light of the upcoming discard ban in EU fisheries. The first section highlights elements of the discard ban in the reformed EU Common Fisheries Policy (CFP). The second section...... and temporary area closures in Kattegat. The third section discusses the lessons learned in the light of implementation of the discard ban. The fourth section sums up the lessons learned; Regional measures of implementation of the discard ban should include all vessels with quota in the region to be regarded...

  17. Cellular strategies for regulating functional and nonfunctional protein aggregation.

    Science.gov (United States)

    Gsponer, Jörg; Babu, M Madan

    2012-11-29

    Growing evidence suggests that aggregation-prone proteins are both harmful and functional for a cell. How do cellular systems balance the detrimental and beneficial effect of protein aggregation? We reveal that aggregation-prone proteins are subject to differential transcriptional, translational, and degradation control compared to nonaggregation-prone proteins, which leads to their decreased synthesis, low abundance, and high turnover. Genetic modulators that enhance the aggregation phenotype are enriched in genes that influence expression homeostasis. Moreover, genes encoding aggregation-prone proteins are more likely to be harmful when overexpressed. The trends are evolutionarily conserved and suggest a strategy whereby cellular mechanisms specifically modulate the availability of aggregation-prone proteins to (1) keep concentrations below the critical ones required for aggregation and (2) shift the equilibrium between the monomeric and oligomeric/aggregate form, as explained by Le Chatelier's principle. This strategy may prevent formation of undesirable aggregates and keep functional assemblies/aggregates under control.

  18. Regulation of mammalian microRNA processing and function by cellular signaling and subcellular localization

    OpenAIRE

    2008-01-01

    For many microRNAs, in many normal tissues and in cancer cells, the cellular levels of mature microRNAs are not simply determined by transcription of microRNA genes. This mini-review will discuss how microRNA biogenesis and function can be regulated by various nuclear and cytoplasmic processing events, including emerging evidence that microRNA pathway components can be selectively regulated by control of their subcellular localization and by modifications that occur during dynamic cellular si...

  19. Oxidative Stress, Redox Regulation and Diseases of Cellular Differentiation

    Science.gov (United States)

    Ye, Zhi-Wei; Zhang, Jie; Townsend, Danyelle M.; Tew, Kenneth D.

    2015-01-01

    Background Within cells, there is a narrow concentration threshold that governs whether reactive oxygen species (ROS) induce toxicity or act as second messengers. Scope of review We discuss current understanding of how ROS arise, facilitate cell signaling, cause toxicities and disease related to abnormal cell differentiation and those (primarily) sulfur based pathways that provide nucleophilicity to offset these effects. Primary conclusions Cellular redox homeostasis mediates a plethora of cellular pathways that determine life and death events. For example, ROS intersect with GSH based enzyme pathways to influence cell differentiation, a process integral to normal hematopoiesis, but also affecting a number of diverse cell differentiation related human diseases. Recent attempts to manage such pathologies have focused on intervening in some of these pathways, with the consequence that differentiation therapy targeting redox homeostasis has provided a platform for drug discovery and development. General Significance The balance between electrophilic oxidative stress and protective biomolecular nucleophiles predisposes the evolution of modern life forms. Imbalances of the two can produce aberrant redox homeostasis with resultant pathologies. Understanding the pathways involved provides opportunities to consider interventional strategies. PMID:25445706

  20. Integration of non-linear cellular mechanisms regulating microvascular perfusion.

    Science.gov (United States)

    Griffith, T M; Edwards, D H

    1999-01-01

    It is becoming increasingly evident that interactions between the different cell types present in the vessel wall and the physical forces that result from blood flow are highly complex. This short article will review evidence that irregular fluctuations in vascular resistance are generated by non-linearity in the control mechanisms intrinsic to the smooth muscle cell and can be classified as chaotic. Non-linear systems theory has provided insights into the mechanisms involved at the cellular level by allowing the identification of dominant control variables and the construction of one-dimensional iterative maps to model vascular dynamics. Experiments with novel peptide inhibitors of gap junctions have shown that the coordination of aggregate responses depends on direct intercellular communication. The sensitivity of chaotic trajectories to perturbation may nevertheless generate a high degree of variability in the response to pharmacological interventions and altered perfusion conditions.

  1. From Syncitium to Regulated Pump: A Cardiac Muscle Cellular Update

    Science.gov (United States)

    Korzick, Donna H.

    2011-01-01

    The primary purpose of this article is to present a basic overview of some key teaching concepts that should be considered for inclusion in an six- to eight-lecture introductory block on the regulation of cardiac performance for graduate students. Within the context of cardiac excitation-contraction coupling, this review incorporates information…

  2. Regulation of REGγ cellular distribution and function by SUMO modification

    Institute of Scientific and Technical Information of China (English)

    Yan Wu; Honglin Luo; Xiaotao Li; Lu Wang; Ping Zhou; Guangqiang Wang; Yu Zeng; Ying Wang; Jian Liu; Bianhong Zhang; Shuang Liu

    2011-01-01

    Discovery of emerging REGy-regulated proteins has accentuated the RECry-proteasome as an important pathway in multiple biological processes, including cell growth, cell cycle regulation, and apoptosis. However, little is known about the regulation of the REGy-proteasome pathway. Here we demonstrate that REGγ can be SUMOylated in vitro and in vivo by SUMO-1, SUMO-2, and SUMO-3. The SUMO-E3 protein inhibitor of activated STAT(PIAS)1physically associates with REGy and promotes SUMOylation of REGy. SUMOylation of RECry was found to occur at multiple sites, including K6, K14, and K12. Mutation analysis indicated that these SUMO sites simultaneously contributed to the SUMOylation status of REGy in cells. Posttranslational modification of REGγ by SUMO conjugation was revealed to mediate cytosolic translocation of REGγ and to cause increased stability of this proteasome activator.SUMOylation-deficient REGγ displayed attenuated ability to degrade p21waf//Cipl due to reduced affinity of the REGγ SUMOylation-defective mutant for p21. Taken together, we report a previously unrecognized mechanism regulating the activity of the proteasome activator REGy. This regulatory mechanism may enable REGy to function as a more potent factor in protein degradation with a broader substrate spectrum.

  3. Cellular adaptation to hypoxia and p53 transcription regulation

    Institute of Scientific and Technical Information of China (English)

    Yang ZHAO; Xue-qun CHEN; Ji-zeng DU

    2009-01-01

    Tumor suppressor p53 is the most frequently mutated gene in human tumors. Meanwhile, under stress conditions, p53 also acts as a transcription factor, regulating the expression of a series of target genes to maintain the integrity of genome. The target genes of p53 can be classified into genes regulating cell cycle arrest, genes involved in apoptosis, and genes inhibiting angiogenesis. p53 protein contains a transactivation domain, a sequence-specific DNA binding domain, a tetramerization domain, a non-specific DNA binding domain that recognizes damaged DNA, and a later identified proline-rich domain. Under stress, p53 proteins accumulate and are activated through two mechanisms. One, involving ataxia telangiectasia-mutated protein (ATM), is that the interaction between p53 and its down-regulation factor murine double minute 2 (MDM2) decreases, leading to p53 phosphorylation on Ser15, as determined by the post-translational mechanism; the other holds that p53 increases and is activated through the binding of ribosomal protein L26 (RPL26) or nucleolin to p53 mRNA 5' untranslated region (UTR), regulating p53 translation. Under hypoxia, p53 decreases transactivation and increases transrepression. The mutations outside the DNA binding domain of p53 also contribute to tumor progress, so further studies on p53 should also be focused on this direction. The subterranean blind mole rat Spalax in Israel is a good model for hypoxia-adaptation. The p53 of Spalax mutated in residue 172 and residue 207 from arginine to lysine, conferring it the ability to survive hypoxic conditions. This model indicates that p53 acts as a master gene of diversity formation during evolution.

  4. Kinetic and Thermodynamic Aspects of Cellular Thiol-Disulfide Redox Regulation

    DEFF Research Database (Denmark)

    Jensen, Kristine Steen; Hansen, Rosa Erritzøe; Winther, Jakob R

    2009-01-01

    Regulation of intracellular thiol-disulfide redox status is an essential part of cellular homeostasis. This involves the regulation of both oxidative and reductive pathways, production of oxidant scavengers and, importantly, the ability of cells to respond to changes in the redox environment...

  5. The cell cycle regulator protein P16 and the cellular senescence of dental follicle cells.

    Science.gov (United States)

    Morsczeck, Christian; Hullmann, Markus; Reck, Anja; Reichert, Torsten E

    2017-08-02

    Cellular senescence is a restricting factor for regenerative therapies with somatic stem cells. We showed previously that the onset of cellular senescence inhibits the osteogenic differentiation in stem cells of the dental follicle (DFCs), although the mechanism remains elusive. Two different pathways are involved in the induction of the cellular senescence, which are driven either by the cell cycle protein P21 or by the cell cycle protein P16. In this study, we investigated the expression of cell cycle proteins in DFCs after the induction of cellular senescence. The induction of cellular senescence was proved by an increased expression of β-galactosidase and an increased population doubling time after a prolonged cell culture. Cellular senescence regulated the expression of cell cycle proteins. The expression of cell cycle protein P16 was up-regulated, which correlates with the induction of cellular senescence markers in DFCs. However, the expression of cyclin-dependent kinases (CDK)2 and 4 and the expression of the cell cycle protein P21 were successively decreased in DFCs. In conclusion, our data suggest that a P16-dependent pathway drives the induction of cellular senescence in DFCs.

  6. Matrix rigidity regulates cancer cell growth and cellular phenotype.

    Directory of Open Access Journals (Sweden)

    Robert W Tilghman

    Full Text Available BACKGROUND: The mechanical properties of the extracellular matrix have an important role in cell growth and differentiation. However, it is unclear as to what extent cancer cells respond to changes in the mechanical properties (rigidity/stiffness of the microenvironment and how this response varies among cancer cell lines. METHODOLOGY/PRINCIPAL FINDINGS: In this study we used a recently developed 96-well plate system that arrays extracellular matrix-conjugated polyacrylamide gels that increase in stiffness by at least 50-fold across the plate. This plate was used to determine how changes in the rigidity of the extracellular matrix modulate the biological properties of tumor cells. The cell lines tested fall into one of two categories based on their proliferation on substrates of differing stiffness: "rigidity dependent" (those which show an increase in cell growth as extracellular rigidity is increased, and "rigidity independent" (those which grow equally on both soft and stiff substrates. Cells which grew poorly on soft gels also showed decreased spreading and migration under these conditions. More importantly, seeding the cell lines into the lungs of nude mice revealed that the ability of cells to grow on soft gels in vitro correlated with their ability to grow in a soft tissue environment in vivo. The lung carcinoma line A549 responded to culture on soft gels by expressing the differentiated epithelial marker E-cadherin and decreasing the expression of the mesenchymal transcription factor Slug. CONCLUSIONS/SIGNIFICANCE: These observations suggest that the mechanical properties of the matrix environment play a significant role in regulating the proliferation and the morphological properties of cancer cells. Further, the multiwell format of the soft-plate assay is a useful and effective adjunct to established 3-dimensional cell culture models.

  7. T cell immunity as a tool for studying epigenetic regulation of cellular differentiation

    Directory of Open Access Journals (Sweden)

    Brendan Edward Russ

    2013-11-01

    Full Text Available Cellular differentiation is regulated by the strict spatial and temporal control of gene expression. This is achieved, in part, by regulating changes in histone post-translational modifications (PTMs and DNA methylation that in-turn, impact transcriptional activity. Further, histone PTMs and DNA methylation are often propagated faithfully at cell division (termed epigenetic propagation, and thus contribute to maintaining cellular identity in the absence of signals driving differentiation. Cardinal features of adaptive T cell immunity include the ability to differentiate in response to infection, resulting in acquisition of immune functions required for pathogen clearance; and the ability to maintain this functional capacity in the long-term, allowing more rapid and effective pathogen elimination following re-infection. These characteristics underpin vaccination strategies by effectively establishing a long-lived T cell population that contributes to an immunologically protective state (termed immunological memory. As we discuss in this review, epigenetic mechanisms provide attractive and powerful explanations for key aspects of T cell-mediated immunity - most obviously and notably, immunological memory, because of the capacity of epigenetic circuits to perpetuate cellular identities in the absence of the initial signals that drive differentiation. Indeed, T cell responses to infection are an ideal model system for studying how epigenetic factors shape cellular differentiation and development generally. This review will examine how epigenetic mechanisms regulate T cell function and differentiation, and how these model systems are providing general insights into the epigenetic regulation of gene transcription during cellular differentiation.

  8. The role of focal adhesion kinase in the regulation of cellular mechanical properties

    Science.gov (United States)

    Mierke, Claudia Tanja

    2013-12-01

    The regulation of mechanical properties is necessary for cell invasion into connective tissue or intra- and extravasation through the endothelium of blood or lymph vessels. Cell invasion is important for the regulation of many healthy processes such as immune response reactions and wound healing. In addition, cell invasion plays a role in disease-related processes such as tumor metastasis and autoimmune responses. Until now the role of focal adhesion kinase (FAK) in regulating mechanical properties of cells and its impact on cell invasion efficiency is still not well known. Thus, this review focuses on mechanical properties regulated by FAK in comparison to the mechano-regulating protein vinculin. Moreover, it points out the connection between cancer cell invasion and metastasis and FAK by showing that FAK regulates cellular mechanical properties required for cellular motility. Furthermore, it sheds light on the indirect interaction of FAK with vinculin by binding to paxillin, which then impairs the binding of paxillin to vinculin. In addition, this review emphasizes whether FAK fulfills regulatory functions similar to vinculin. In particular, it discusses the differences and the similarities between FAK and vinculin in regulating the biomechanical properties of cells. Finally, this paper highlights that both focal adhesion proteins, vinculin and FAK, synergize their functions to regulate the mechanical properties of cells such as stiffness and contractile forces. Subsequently, these mechanical properties determine cellular invasiveness into tissues and provide a source sink for future drug developments to inhibit excessive cell invasion and hence, metastases formation.

  9. Polyamines regulate cell growth and cellular methylglyoxal in high-glucose medium independently of intracellular glutathione.

    Science.gov (United States)

    Kwak, Min-Kyu; Lee, Mun-Hyoung; Park, Seong-Jun; Shin, Sang-Min; Liu, Rui; Kang, Sa-Ouk

    2016-03-01

    Polyamines can presumably inhibit protein glycation, when associated with the methylglyoxal inevitably produced during glycolysis. Herein, we hypothesized a nonenzymatic interaction between putrescine and methylglyoxal in putrescine-deficient or -overexpressing Dictyostelium cells in high-glucose medium, which can control methylglyoxal production. Putrescine was essentially required for growth rescue accompanying methylglyoxal detoxification when cells underwent growth defect and cell cycle G1-arrest when supplemented with high glucose. Furthermore, methylglyoxal regulation by putrescine seemed to be a parallel pathway independent of the changes in cellular glutathione content in high-glucose medium. Consequently, we suggest that Dictyostelium cells need polyamines for normal growth and cellular methylglyoxal regulation.

  10. 77 FR 22185 - Golden Nematode; Removal of Regulated Areas

    Science.gov (United States)

    2012-04-13

    ... Inspection Service 7 CFR Part 301 Golden Nematode; Removal of Regulated Areas AGENCY: Animal and Plant Health... townships of Elba and Byron in Genesee County, NY, from the list of generally infested areas. Surveys have... regulation of these areas was no longer necessary. As a result of that action, all the areas in...

  11. A cellular automaton for population diffusion in the homogeneous rectangular area

    Directory of Open Access Journals (Sweden)

    WenJun Zhang

    2015-03-01

    Full Text Available In this paper, a cellular automaton for population diffusion was introduced. A group of discrete partial differential equations was used to simulate population diffusion in the homogeneous rectangular area. The population dynamics was described by Malthus model, Logistic model, and oscillation model. The cellular automaton can be used to analyze the effects of initial distribution of organisms on diffusion process and distribution pattern, to estimate the diffusion speed and possible diffusion directions, and to determine the major regions occupied by organisms.

  12. AMPK Maintains Cellular Metabolic Homeostasis through Regulation of Mitochondrial Reactive Oxygen Species

    Directory of Open Access Journals (Sweden)

    Rebecca C. Rabinovitch

    2017-10-01

    Full Text Available Reactive oxygen species (ROS are continuously produced as a by-product of mitochondrial metabolism and eliminated via antioxidant systems. Regulation of mitochondrially produced ROS is required for proper cellular function, adaptation to metabolic stress, and bypassing cellular senescence. Here, we report non-canonical regulation of the cellular energy sensor AMP-activated protein kinase (AMPK by mitochondrial ROS (mROS that functions to maintain cellular metabolic homeostasis. We demonstrate that mitochondrial ROS are a physiological activator of AMPK and that AMPK activation triggers a PGC-1α-dependent antioxidant response that limits mitochondrial ROS production. Cells lacking AMPK activity display increased mitochondrial ROS levels and undergo premature senescence. Finally, we show that AMPK-PGC-1α-dependent control of mitochondrial ROS regulates HIF-1α stabilization and that mitochondrial ROS promote the Warburg effect in cells lacking AMPK signaling. These data highlight a key function for AMPK in sensing and resolving mitochondrial ROS for stress resistance and maintaining cellular metabolic balance.

  13. Tissue organization by cadherin adhesion molecules: dynamic molecular and cellular mechanisms of morphogenetic regulation

    Science.gov (United States)

    Niessen, Carien M.; Leckband, Deborah; Yap, Alpha S.

    2013-01-01

    This review addresses the cellular and molecular mechanisms of cadherin-based tissue morphogenesis. Tissue physiology is profoundly influenced by the distinctive organizations of cells in organs and tissues. In metazoa, adhesion receptors of the classical cadherin family play important roles in establishing and maintaining such tissue organization. Indeed, it is apparent that cadherins participate in a range of morphogenetic events that range from support of tissue integrity to dynamic cellular rearrangements. A comprehensive understanding of cadherin-based morphogenesis must then define the molecular and cellular mechanisms that support these distinct cadherin biologies. Here we focus on four key mechanistic elements: the molecular basis for adhesion through cadherin ectodomains; the regulation of cadherin expression at the cell surface; cooperation between cadherins and the actin cytoskeleton; and regulation by cell signaling. We discuss current progress and outline issues for further research in these fields. PMID:21527735

  14. 7 CFR 905.16 - Regulation Area II.

    Science.gov (United States)

    2010-01-01

    ... County; thence East to the line between Ranges 40 East and 41 East; thence South to the West Palm Beach... TANGELOS GROWN IN FLORIDA Order Regulating Handling Definitions § 905.16 Regulation Area II. Regulation Area II is defined as the “Indian River District”, and shall include that part of the State of...

  15. BICD2, dynactin, and LIS1 cooperate in regulating dynein recruitment to cellular structures

    NARCIS (Netherlands)

    D. Splinter (Daniël); D.S. Razafsky (David); M.A. Schlager (Max); A. Serra-Marques (Andrea); I. Grigoriev (Ilya); J.A.A. Demmers (Jeroen); N. Keijzer (Nanda); K. Jiang (Kai); S. Poser; A. Hyman (Anthony); C.C. Hoogenraad (Casper); S.J. King (Stephen); A.S. Akhmanova (Anna)

    2012-01-01

    textabstractCytoplasmic dynein is the major microtubule minus-end-directed cellular motor. Most dynein activities require dynactin, but the mechanisms regulating cargo-dependent dynein-dynactin interaction are poorly understood. In this study, we focus on dynein-dynactin recruitment to cargo by the

  16. Lysine acetylation targets protein complexes and co-regulates major cellular functions

    DEFF Research Database (Denmark)

    Choudhary, Chuna Ram; Kumar, Chanchal; Gnad, Florian;

    2009-01-01

    Lysine acetylation is a reversible posttranslational modification of proteins and plays a key role in regulating gene expression. Technological limitations have so far prevented a global analysis of lysine acetylation's cellular roles. We used high-resolution mass spectrometry to identify 3600...

  17. BICD2, dynactin, and LIS1 cooperate in regulating dynein recruitment to cellular structures

    NARCIS (Netherlands)

    D. Splinter (Daniël); D.S. Razafsky (David); M.A. Schlager (Max); A. Serra-Marques (Andrea); I. Grigoriev (Ilya); J.A.A. Demmers (Jeroen); N. Keijzer (Nanda); K. Jiang (Kai); S. Poser; A. Hyman (Anthony); C.C. Hoogenraad (Casper); S.J. King (Stephen); A.S. Akhmanova (Anna)

    2012-01-01

    textabstractCytoplasmic dynein is the major microtubule minus-end-directed cellular motor. Most dynein activities require dynactin, but the mechanisms regulating cargo-dependent dynein-dynactin interaction are poorly understood. In this study, we focus on dynein-dynactin recruitment to cargo by the

  18. 76 FR 60357 - Golden Nematode; Removal of Regulated Areas

    Science.gov (United States)

    2011-09-29

    ... Animal and Plant Health Inspection Service 7 CFR Part 301 Golden Nematode; Removal of Regulated Areas... Genesee County, NY, from the list of generally infested areas. Surveys have shown that the fields in these two townships are free of golden nematode, and we have determined that regulation of these areas is...

  19. 76 FR 52543 - European Larch Canker; Expansion of Regulated Areas

    Science.gov (United States)

    2011-08-23

    ... Areas AGENCY: Animal and Plant Health Inspection Service, USDA. ACTION: Interim rule and request for comments. SUMMARY: We are amending the domestic quarantine regulations to expand the regulated area for European larch canker to include additional areas in Maine. We are also correcting some...

  20. Substrate Stiffness and Cell Area Predict Cellular Traction Stresses in Single Cells and Cells in Contact.

    Science.gov (United States)

    Califano, Joseph P; Reinhart-King, Cynthia A

    2010-03-01

    Cells generate traction stresses against their substrate during adhesion and migration, and traction stresses are used in part by the cell to sense the substrate. While it is clear that traction stresses, substrate stiffness, and cell area are related, it is unclear whether or how area and substrate stiffness affect force generation in cells. Moreover, multiple studies have investigated traction stresses of single cells, but few have focused on forces exerted by cells in contact, which more closely mimics the in vivo environment. Here, cellular traction forces were measured where cell area was modulated by ligand density or substrate stiffness. We coupled these measurements with a multilinear regression model to show that both projected cell area and underlying substrate stiffness are significant predictors of traction forces in endothelial cells, and interestingly, substrate ligand density is not. We further explored the effect of cell-cell contact on the interplay between cell area, substrate stiffness, and force generation and found that again both area and stiffness play a significant role in cell force generation. These data indicate that cellular traction force cannot be determined by cell area alone and that underlying substrate stiffness is a significant contributor to traction force generation.

  1. Regulation of cellular senescence by the essential caveolar component PTRF/Cavin-1

    Institute of Scientific and Technical Information of China (English)

    Lin Bai; Xiaoli Deng; Juanjuan Li; Miao Wang; Qian Li; Wei An; Deli A; Yu-Sheng Cong

    2011-01-01

    Polymerase I and transcript release factor (PTRF, also known as Cavin-1) is an essential component in the biogenesis and function of caveolae. Here, we show that PTRF expression is increased in senescent human fibroblasts.Importantly, overexpression of PTRF induced features characteristic of cellular senescence, whereas reduced PTRF expression extended the cellular replicative lifespan. Interestingly, we found that PTRF localized primarily to the nuclei of young and quiescent WI-38 human fibroblasts, but translocated to the cytosol and plasma membrane during cellular senescence. Furthermore, electron microscopic analysis demonstrated an increased number of caveolar structures in senescent and PTRF-transfected WI-38 cells. Our data suggest that the role of PTRF in cellular senes cence is dependent on its targeting to caveolae and its interaction with caveolin-l, which appeared to be regulated by the phosphorylation of PTRF. Taken together, our findings identify PTRF as a novel regulator of cellular senescence that acts through the p53/p21 and caveolar pathways.

  2. Integrin-linked kinase regulates cellular mechanics facilitating the motility in 3D extracellular matrices.

    Science.gov (United States)

    Kunschmann, Tom; Puder, Stefanie; Fischer, Tony; Perez, Jeremy; Wilharm, Nils; Mierke, Claudia Tanja

    2017-03-01

    The motility of cells plays an important role for many processes such as wound healing and malignant progression of cancer. The efficiency of cell motility is affected by the microenvironment. The connection between the cell and its microenvironment is facilitated by cell-matrix adhesion receptors and upon their activation focal adhesion proteins such as integrin-linked kinase (ILK) are recruited to sites of focal adhesion formation. In particular, ILK connects cell-matrix receptors to the actomyosin cytoskeleton. However, ILK's role in cell mechanics regulating cellular motility in 3D collagen matrices is still not well understood. We suggest that ILK facilitates 3D motility by regulating cellular mechanical properties such as stiffness and force transmission. Thus, ILK wild-type and knock-out cells are analyzed for their ability to migrate on 2D substrates serving as control and in dense 3D extracellular matrices. Indeed, ILK wild-type cells migrated faster on 2D substrates and migrated more numerous and deeper in 3D matrices. Hence, we analyzed cellular deformability, Young's modulus (stiffness) and adhesion forces. We found that ILK wild-type cells are less deformable (stiffer) and produce higher cell-matrix adhesion forces compared to ILK knock-out cells. Finally, ILK is essential for providing cellular mechanical stiffness regulating 3D motility.

  3. Reactive oxygen species (ROS) homeostasis and redox regulation in cellular signaling.

    Science.gov (United States)

    Ray, Paul D; Huang, Bo-Wen; Tsuji, Yoshiaki

    2012-05-01

    Reactive oxygen species (ROS) are generated during mitochondrial oxidative metabolism as well as in cellular response to xenobiotics, cytokines, and bacterial invasion. Oxidative stress refers to the imbalance due to excess ROS or oxidants over the capability of the cell to mount an effective antioxidant response. Oxidative stress results in macromolecular damage and is implicated in various disease states such as atherosclerosis, diabetes, cancer, neurodegeneration, and aging. Paradoxically, accumulating evidence indicates that ROS also serve as critical signaling molecules in cell proliferation and survival. While there is a large body of research demonstrating the general effect of oxidative stress on signaling pathways, less is known about the initial and direct regulation of signaling molecules by ROS, or what we term the "oxidative interface." Cellular ROS sensing and metabolism are tightly regulated by a variety of proteins involved in the redox (reduction/oxidation) mechanism. This review focuses on the molecular mechanisms through which ROS directly interact with critical signaling molecules to initiate signaling in a broad variety of cellular processes, such as proliferation and survival (MAP kinases, PI3 kinase, PTEN, and protein tyrosine phosphatases), ROS homeostasis and antioxidant gene regulation (thioredoxin, peroxiredoxin, Ref-1, and Nrf-2), mitochondrial oxidative stress, apoptosis, and aging (p66Shc), iron homeostasis through iron-sulfur cluster proteins (IRE-IRP), and ATM-regulated DNA damage response.

  4. FIH Regulates Cellular Metabolism through Hydroxylation of the Deubiquitinase OTUB1.

    Directory of Open Access Journals (Sweden)

    Carsten C Scholz

    2016-01-01

    Full Text Available The asparagine hydroxylase, factor inhibiting HIF (FIH, confers oxygen-dependence upon the hypoxia-inducible factor (HIF, a master regulator of the cellular adaptive response to hypoxia. Studies investigating whether asparagine hydroxylation is a general regulatory oxygen-dependent modification have identified multiple non-HIF targets for FIH. However, the functional consequences of this outside of the HIF pathway remain unclear. Here, we demonstrate that the deubiquitinase ovarian tumor domain containing ubiquitin aldehyde binding protein 1 (OTUB1 is a substrate for hydroxylation by FIH on N22. Mutation of N22 leads to a profound change in the interaction of OTUB1 with proteins important in cellular metabolism. Furthermore, in cultured cells, overexpression of N22A mutant OTUB1 impairs cellular metabolic processes when compared to wild type. Based on these data, we hypothesize that OTUB1 is a target for functional hydroxylation by FIH. Additionally, we propose that our results provide new insight into the regulation of cellular energy metabolism during hypoxic stress and the potential for targeting hydroxylases for therapeutic benefit.

  5. Integrated cellular network of transcription regulations and protein-protein interactions

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    Chen Bor-Sen

    2010-03-01

    Full Text Available Abstract Background With the accumulation of increasing omics data, a key goal of systems biology is to construct networks at different cellular levels to investigate cellular machinery of the cell. However, there is currently no satisfactory method to construct an integrated cellular network that combines the gene regulatory network and the signaling regulatory pathway. Results In this study, we integrated different kinds of omics data and developed a systematic method to construct the integrated cellular network based on coupling dynamic models and statistical assessments. The proposed method was applied to S. cerevisiae stress responses, elucidating the stress response mechanism of the yeast. From the resulting integrated cellular network under hyperosmotic stress, the highly connected hubs which are functionally relevant to the stress response were identified. Beyond hyperosmotic stress, the integrated network under heat shock and oxidative stress were also constructed and the crosstalks of these networks were analyzed, specifying the significance of some transcription factors to serve as the decision-making devices at the center of the bow-tie structure and the crucial role for rapid adaptation scheme to respond to stress. In addition, the predictive power of the proposed method was also demonstrated. Conclusions We successfully construct the integrated cellular network which is validated by literature evidences. The integration of transcription regulations and protein-protein interactions gives more insight into the actual biological network and is more predictive than those without integration. The method is shown to be powerful and flexible and can be used under different conditions and for different species. The coupling dynamic models of the whole integrated cellular network are very useful for theoretical analyses and for further experiments in the fields of network biology and synthetic biology.

  6. 76 FR 58105 - Regulated Navigation Area; Saugus River, Lynn, MA

    Science.gov (United States)

    2011-09-20

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA11 Regulated Navigation Area; Saugus River, Lynn, MA AGENCY... River in Lynn, MA. Establishing this temporary rule will allow the necessary stabilization work to be... on the Energy Systems Pipeline Bridge on the Saugus River in Lynn, MA. The regulated area...

  7. 75 FR 41073 - South American Cactus Moth Regulations; Quarantined Areas

    Science.gov (United States)

    2010-07-15

    ... Inspection Service 7 CFR Part 301 South American Cactus Moth Regulations; Quarantined Areas AGENCY: Animal... are amending the South American cactus moth regulations by adding the State of Louisiana to the list of areas quarantined because of South American cactus moth. As a result of this action,...

  8. Sterol regulation of acetyl coenzyme A carboxylase: a mechanism for coordinate control of cellular lipid.

    OpenAIRE

    Lopez, J.M.; Bennett, M K; Sanchez, H B; Rosenfeld, J M; Osborne, T E

    1996-01-01

    Transcription from the housekeeping promoter for the acetyl coenzyme A carboxylase (ACC) gene, which encodes the rate-controlling enzyme of fatty acid biosynthesis, is shown to be regulated by cellular sterol levels through novel binding sites for the sterol-sensitive sterol regulatory element binding protein (SREBP)-1 transcription factor. The position of the SREBP sites relative to those for the ubiquitous auxiliary transcription factor Sp1 is reminiscent of that previously described for th...

  9. 76 FR 44199 - Area Risk Protection Insurance Regulations and Area Risk Protection Insurance Crop Provisions

    Science.gov (United States)

    2011-07-22

    ... Risk Protection Insurance Regulations and Area Risk Protection Insurance Crop Provisions; Proposed Rule... OF AGRICULTURE Federal Crop Insurance Corporation 7 CFR Part 407 RIN 0563-AC25 Area Risk Protection Insurance Regulations and Area Risk Protection Insurance Crop Provisions AGENCY: Federal Crop...

  10. 78 FR 38483 - Area Risk Protection Insurance Regulations and Area Risk Protection Insurance Crop Provisions

    Science.gov (United States)

    2013-06-26

    ... Risk Protection Insurance Regulations and Area Risk Protection Insurance Crop Provisions; Final Rule #0...; ] DEPARTMENT OF AGRICULTURE Federal Crop Insurance Corporation 7 CFR Part 407 RIN 0563-AC25 Area Risk Protection Insurance Regulations and Area Risk Protection Insurance Crop Provisions AGENCY: Federal...

  11. Stem-loop binding protein is a multifaceted cellular regulator of HIV-1 replication

    Science.gov (United States)

    Tucker, Lynne D.; Asara, John M.; Cheruiyot, Collins K.; Lu, Huafei; Wu, Zhijin J.; Newstein, Michael C.; Dooner, Mark S.; Friedman, Jennifer; Lally, Michelle A.; Ramratnam, Bharat

    2016-01-01

    A rare subset of HIV-1–infected individuals is able to maintain plasma viral load (VL) at low levels without antiretroviral treatment. Identifying the mechanisms underlying this atypical response to infection may lead to therapeutic advances for treating HIV-1. Here, we developed a proteomic analysis to compare peripheral blood cell proteomes in 20 HIV-1–infected individuals who maintained either high or low VL with the aim of identifying host factors that impact HIV-1 replication. We determined that the levels of multiple histone proteins were markedly decreased in cohorts of individuals with high VL. This reduction was correlated with lower levels of stem-loop binding protein (SLBP), which is known to control histone metabolism. Depletion of cellular SLBP increased promoter engagement with the chromatin structures of the host gene high mobility group protein A1 (HMGA1) and viral long terminal repeat (LTR), which led to higher levels of HIV-1 genomic integration and proviral transcription. Further, we determined that TNF-α regulates expression of SLBP and observed that plasma TNF-α levels in HIV-1–infected individuals correlated directly with VL levels and inversely with cellular SLBP levels. Our findings identify SLBP as a potentially important cellular regulator of HIV-1, thereby establishing a link between histone metabolism, inflammation, and HIV-1 infection. PMID:27454292

  12. Performance Analysis of Solar Photovoltaic Cells for Telecommunication Cellular Network in Remote Areas of Pakistan

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    Abdul Ghayur

    2016-10-01

    Full Text Available In this research design and implementation of solar photo voltaic cell is done for base transceiver system (BTS of telecom cellular networks in remote areas of Pakistan, to accomplish this task investigation is done regarding the present alternate power source of base transceiver system (BTS that is the generator sets used as a stand-by, prime and t-prime source. This research will examine that generator sets fuel consumption and maintenance cost is considerably high and the cellular company has to pay a lot to keep a site on air and to overcome the connectivity issues.To resolve these issues this research is aimed to implement solar technology on BTS, for this purpose exploration is done regarding BTS rectifier system and suggested to use power on distribution systems 16 (PODS 16, latest technology evolution (LTE based instead of the simple BTS rectifier, this new rectifier is intelligent and has redundant ways to overcome power issues as it has the capability to work directly on solar panel equipments and it requires DC supply. Other important factor is that solar panel recharge batteries for power backup and to keep the site on air during night time. Different cost comparison of solar and generator sets have been done by taking real data of different remote areas sites and in the end it is concluded that solar is the alternate costless, environmental friendly source of energy for BTS and can be implemented both for off-grid and on-grid systems.

  13. HPV16 E2 could act as down-regulator in cellular genes implicated in apoptosis, proliferation and cell differentiation

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    Valencia-Hernández Armando

    2011-05-01

    Full Text Available Abstract Background Human Papillomavirus (HPV E2 plays several important roles in the viral cycle, including the transcriptional regulation of the oncogenes E6 and E7, the regulation of the viral genome replication by its association with E1 helicase and participates in the viral genome segregation during mitosis by its association with the cellular protein Brd4. It has been shown that E2 protein can regulate negative or positively the activity of several cellular promoters, although the precise mechanism of this regulation is uncertain. In this work we constructed a recombinant adenoviral vector to overexpress HPV16 E2 and evaluated the global pattern of biological processes regulated by E2 using microarrays expression analysis. Results The gene expression profile was strongly modified in cells expressing HPV16 E2, finding 1048 down-regulated genes, and 581 up-regulated. The main cellular pathway modified was WNT since we found 28 genes down-regulated and 15 up-regulated. Interestingly, this pathway is a convergence point for regulating the expression of genes involved in several cellular processes, including apoptosis, proliferation and cell differentiation; MYCN, JAG1 and MAPK13 genes were selected to validate by RT-qPCR the microarray data as these genes in an altered level of expression, modify very important cellular processes. Additionally, we found that a large number of genes from pathways such as PDGF, angiogenesis and cytokines and chemokines mediated inflammation, were also modified in their expression. Conclusions Our results demonstrate that HPV16 E2 has regulatory effects on cellular gene expression in HPV negative cells, independent of the other HPV proteins, and the gene profile observed indicates that these effects could be mediated by interactions with cellular proteins. The cellular processes affected suggest that E2 expression leads to the cells in to a convenient environment for a replicative cycle of the virus.

  14. The role of topography in the scaling distribution of landslide areas: A cellular automata modeling approach

    Science.gov (United States)

    Liucci, Luisa; Melelli, Laura; Suteanu, Cristian; Ponziani, Francesco

    2017-08-01

    Power law scaling has been widely observed in the frequency distribution of landslide sizes. The exponent of the power-law characterizes the probability of landslide magnitudes and it thus represents an important parameter for hazard assessment. The reason for the universal scaling behavior of landslides is still debated and the role of topography has been explored in terms of possible explanation for this type of behavior. We built a simple cellular automata model to investigate this issue, as well as the relationships between the scaling properties of landslide areas and the changes suffered by the topographic surface affected by landslides. The dynamics of the model is controlled by a temporal rate of weakening, which drives the system to instability, and by topography, which defines both the quantity of the displaced mass and the direction of the movement. Results show that the model is capable of reproducing the scaling behavior of real landslide areas and suggest that topography is a good candidate to explain their scale-invariance. In the model, the values of the scaling exponents depend on how fast the system is driven to instability; they are less sensitive to the duration of the driving rate, thus suggesting that the probability of landslide areas could depend on the intensity of the triggering mechanism rather than on its duration, and on the topographic setting of the area. Topography preserves the information concerning the statistical distribution of areas of landslides caused by a driving mechanism of given intensity and duration.

  15. Disruption of a cystine transporter downregulates expression of genes involved in sulfur regulation and cellular respiration

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    Jessica A. Simpkins

    2016-06-01

    Full Text Available Cystine and cysteine are important molecules for pathways such as redox signaling and regulation, and thus identifying cellular deficits upon deletion of the Saccharomyces cerevisiae cystine transporter Ers1p allows for a further understanding of cystine homeostasis. Previous complementation studies using the human ortholog suggest yeast Ers1p is a cystine transporter. Human CTNS encodes the protein Cystinosin, a cystine transporter that is embedded in the lysosomal membrane and facilitates the export of cystine from the lysosome. When CTNS is mutated, cystine transport is disrupted, leading to cystine accumulation, the diagnostic hallmark of the lysosomal storage disorder cystinosis. Here, we provide biochemical evidence for Ers1p-dependent cystine transport. However, the accumulation of intracellular cystine is not observed when the ERS1 gene is deleted from ers1-Δ yeast, supporting the existence of modifier genes that provide a mechanism in ers1-Δ yeast that prevents or corrects cystine accumulation. Upon comparison of the transcriptomes of isogenic ERS1+ and ers1-Δ strains of S. cerevisiae by DNA microarray followed by targeted qPCR, sixteen genes were identified as being differentially expressed between the two genotypes. Genes that encode proteins functioning in sulfur regulation, cellular respiration, and general transport were enriched in our screen, demonstrating pleiotropic effects of ers1-Δ. These results give insight into yeast cystine regulation and the multiple, seemingly distal, pathways that involve proper cystine recycling.

  16. Disruption of a cystine transporter downregulates expression of genes involved in sulfur regulation and cellular respiration

    Science.gov (United States)

    Simpkins, Jessica A.; Rickel, Kirby E.; Madeo, Marianna; Ahlers, Bethany A.; Carlisle, Gabriel B.; Nelson, Heidi J.; Cardillo, Andrew L.; Weber, Emily A.; Vitiello, Peter F.; Pearce, David A.

    2016-01-01

    ABSTRACT Cystine and cysteine are important molecules for pathways such as redox signaling and regulation, and thus identifying cellular deficits upon deletion of the Saccharomyces cerevisiae cystine transporter Ers1p allows for a further understanding of cystine homeostasis. Previous complementation studies using the human ortholog suggest yeast Ers1p is a cystine transporter. Human CTNS encodes the protein Cystinosin, a cystine transporter that is embedded in the lysosomal membrane and facilitates the export of cystine from the lysosome. When CTNS is mutated, cystine transport is disrupted, leading to cystine accumulation, the diagnostic hallmark of the lysosomal storage disorder cystinosis. Here, we provide biochemical evidence for Ers1p-dependent cystine transport. However, the accumulation of intracellular cystine is not observed when the ERS1 gene is deleted from ers1-Δ yeast, supporting the existence of modifier genes that provide a mechanism in ers1-Δ yeast that prevents or corrects cystine accumulation. Upon comparison of the transcriptomes of isogenic ERS1+ and ers1-Δ strains of S. cerevisiae by DNA microarray followed by targeted qPCR, sixteen genes were identified as being differentially expressed between the two genotypes. Genes that encode proteins functioning in sulfur regulation, cellular respiration, and general transport were enriched in our screen, demonstrating pleiotropic effects of ers1-Δ. These results give insight into yeast cystine regulation and the multiple, seemingly distal, pathways that involve proper cystine recycling. PMID:27142334

  17. BAF180 regulates cellular senescence and hematopoietic stem cell homeostasis through p21.

    Science.gov (United States)

    Lee, Hyemin; Dai, Fangyan; Zhuang, Li; Xiao, Zhen-Dong; Kim, Jongchan; Zhang, Yilei; Ma, Li; You, M James; Wang, Zhong; Gan, Boyi

    2016-04-12

    BAF180 (also called PBRM1), a subunit of the SWI/SNF complex, plays critical roles in the regulation of chromatin remodeling and gene transcription, and is frequently mutated in several human cancers. However, the role of mammalian BAF180 in tumor suppression and tissue maintenance in vivo remains largely unknown. Here, using a conditional somatic knockout approach, we explored the cellular and organismal functions of BAF180 in mouse. BAF180 deletion in primary mouse embryonic fibroblasts (MEFs) triggers profound cell cycle arrest, premature cellular senescence, without affecting DNA damage response or chromosomal integrity. While somatic deletion of BAF180 in adult mice does not provoke tumor development, BAF180 deficient mice exhibit defects in hematopoietic system characterized by progressive reduction of hematopoietic stem cells (HSCs), defective long-term repopulating potential, and hematopoietic lineage developmental aberrations. BAF180 deletion results in elevated p21 expression in both MEFs and HSCs. Mechanistically, we showed that BAF180 binds to p21 promoter, and BAF180 deletion enhances the binding of modified histones associated with transcriptional activation on p21 promoter. Deletion of p21 rescues cell cycle arrest and premature senescence in BAF180 deficient MEFs, and partially rescues hematopoietic defects in BAF180 deficient mice. Together, our study identifies BAF180 as a critical regulator of cellular senescence and HSC homeostasis, which is at least partially regulated through BAF180-mediated suppression of p21 expression. Our results also suggest that senescence triggered by BAF180 inactivation may serve as a failsafe mechanism to restrain BAF180 deficiency-associated tumor development, providing a conceptual framework to further understand BAF180 function in tumor biology.

  18. Annexin A2: Its Molecular Regulation and Cellular Expression in Cancer Development

    Directory of Open Access Journals (Sweden)

    Chi-Yun Wang

    2014-01-01

    Full Text Available Annexin A2 (ANXA2 orchestrates multiple biologic processes and clinical associations, especially in cancer progression. The structure of ANXA2 affects its cellular localization and function. However, posttranslational modification and protease-mediated N-terminal cleavage also play critical roles in regulating ANXA2. ANXA2 expression levels vary among different types of cancers. With some cancers, ANXA2 can be used for the detection and diagnosis of cancer and for monitoring cancer progression. ANXA2 is also required for drug-resistance. This review discusses the feasibility of ANXA2 which is active in cancer development and can be a therapeutic target in cancer management.

  19. Anterior gradient protein-2 is a regulator of cellular adhesion in prostate cancer.

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    Diptiman Chanda

    Full Text Available Anterior Gradient Protein (AGR-2 is reported to be over-expressed in many epithelial cancers and promotes metastasis. A clear-cut mechanism for its observed function(s has not been previously identified. We found significant upregulation of AGR-2 expression in a bone metastatic prostate cancer cell line, PC3, following culturing in bone marrow-conditioned medium. Substantial AGR-2 expression was also confirmed in prostate cancer tissue specimens in patients with bone lesions. By developing stable clones of PC3 cells with varying levels of AGR-2 expression, we identified that abrogation of AGR-2 significantly reduced cellular attachment to fibronectin, collagen I, collagen IV, laminin I and fibrinogen. Loss of cellular adhesion was associated with sharp decrease in the expression of α4, α5, αV, β3 and β4 integrins. Failure to undergo apoptosis following detachment is a hallmark of epithelial cancer metastasis. The AGR-2-silenced PC3 cells showed higher resistance to Tumor necrosis factor-related apoptosis- inducing ligand (TRAIL induced apoptosis in vitro. This observation was also supported by significantly reduced Caspase-3 expression in AGR-2-silenced PC3 cells, which is a key effector of both extrinsic and intrinsic death signaling pathways. These data suggest that AGR-2 influence prostate cancer metastasis by regulation of cellular adhesion and apoptosis.

  20. Membrane plasmalogen composition and cellular cholesterol regulation: a structure activity study

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    Su-Myat Khine K

    2010-06-01

    Full Text Available Abstract Background Disrupted cholesterol regulation leading to increased circulating and membrane cholesterol levels is implicated in many age-related chronic diseases such as cardiovascular disease (CVD, Alzheimer's disease (AD, and cancer. In vitro and ex vivo cellular plasmalogen deficiency models have been shown to exhibit impaired intra- and extra-cellular processing of cholesterol. Furthermore, depleted brain plasmalogens have been implicated in AD and serum plasmalogen deficiencies have been linked to AD, CVD, and cancer. Results Using plasmalogen deficient (NRel-4 and plasmalogen sufficient (HEK293 cells we investigated the effect of species-dependent plasmalogen restoration/augmentation on membrane cholesterol processing. The results of these studies indicate that the esterification of cholesterol is dependent upon the amount of polyunsaturated fatty acid (PUFA-containing ethanolamine plasmalogen (PlsEtn present in the membrane. We further elucidate that the concentration-dependent increase in esterified cholesterol observed with PUFA-PlsEtn was due to a concentration-dependent increase in sterol-O-acyltransferase-1 (SOAT1 levels, an observation not reproduced by 3-hydroxy-3-methyl-glutaryl-CoA (HMG-CoA reductase inhibition. Conclusion The present study describes a novel mechanism of cholesterol regulation that is consistent with clinical and epidemiological studies of cholesterol, aging and disease. Specifically, the present study describes how selective membrane PUFA-PlsEtn enhancement can be achieved using 1-alkyl-2-PUFA glycerols and through this action reduce levels of total and free cholesterol in cells.

  1. Regulation of cellular marker modulated upon irradiation of low power laser light in burn injured mice

    Science.gov (United States)

    Rathnakar, Bharath; Prabhu, Vijendra; Rao, Bola Sadashiva Satish; Chandra, Subhash; Rai, Sharada; Mahato, Krishna Kishore

    2016-12-01

    The present study intends to understand the importance of cellular marker in tissue regeneration regulated upon irradiation of low power laser light in burn inflicted mice. Under anesthetic conditions, the thermal injury was induced on Swiss albino mice of either sex. Following injury, the animals were randomly divided into three groups; i. e., un-illuminated control, the group treated with 5% Povidone iodine (reference standard) and single exposure of 3 J/cm2 (830 nm). Burn tissue samples from each group were excised at day 6 post burn injury upon euthanization and used for histological and immunohistochemical analysis. Haematoxylin and Eosin (H and E) staining was performed on the selected sections to asses proliferation and angiogenesis at day 6 post-injury. For immunohistochemical analysis, tissue sections from all the three treatment groups on day 6 were stained using specific antibody against Proliferating cell nuclear antigen (PCNA). The results of the histological and immunohistochemical analysis showed improved tissue restoration in animals treated with optimal laser influence as compared to un-illuminated controls. The findings of present study clearly demonstrated the beneficial effects of 830 nm laser in burn wound healing and its influence in regulating the cellular marker.

  2. HTLV Tax: a fascinating multifunctional co-regulator of viral and cellular pathways

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    Robert eCurrer

    2012-11-01

    Full Text Available Human T cell lymphotropic virus type 1 (HTLV-1 has been identified as the causative agent of adult T cell leukemia (ATL and HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP. The virus infects between 15 and 20 million people worldwide of which approximately 2 to 5% develop ATL. The past 35 years of research have yielded significant insight into the pathogenesis of HTLV-1, including the molecular characterization of Tax, the viral transactivator and oncoprotein. In spite of these efforts, the mechanisms of oncogenesis of this pleiotropic protein remain to be fully elucidated. In this review, we illustrate the multiple oncogenic roles of Tax by summarizing a recent body of literature that refines our understanding of cellular transformation. A focused range of topics are discussed in this review including Tax-mediated regulation of the viral promoter and other cellular pathways, particularly the connection of the NF-κB pathway to both post-translational modifications of Tax and sub-cellular localization. Specifically, recent research on polyubiquitination of Tax as it relates to the activation of the IkappaB kinase (IKK complex is highlighted. Regulation of the cell cycle and DNA damage responses due to Tax are also discussed, including Tax interaction with minichromosome maintenance proteins and the role of Tax in chromatin remodeling. The recent identification of HTLV-3 has amplified the importance of the characterization of emerging viral pathogens. The challenge of the molecular determination of pathogenicity and malignant disease of this virus lies in the comparison of the viral transactivators of HTLV-1, -2, and -3 in terms of transformation and immortalization. Consequently, differences between the three proteins are currently being studied to determine what factors are required for the differences in tumorogenesis.

  3. Cellular prion protein expression is not regulated by the Alzheimer's amyloid precursor protein intracellular domain.

    Directory of Open Access Journals (Sweden)

    Victoria Lewis

    Full Text Available There is increasing evidence of molecular and cellular links between Alzheimer's disease (AD and prion diseases. The cellular prion protein, PrP(C, modulates the post-translational processing of the AD amyloid precursor protein (APP, through its inhibition of the β-secretase BACE1, and oligomers of amyloid-β bind to PrP(C which may mediate amyloid-β neurotoxicity. In addition, the APP intracellular domain (AICD, which acts as a transcriptional regulator, has been reported to control the expression of PrP(C. Through the use of transgenic mice, cell culture models and manipulation of APP expression and processing, this study aimed to clarify the role of AICD in regulating PrP(C. Over-expression of the three major isoforms of human APP (APP(695, APP(751 and APP(770 in cultured neuronal and non-neuronal cells had no effect on the level of endogenous PrP(C. Furthermore, analysis of brain tissue from transgenic mice over-expressing either wild type or familial AD associated mutant human APP revealed unaltered PrP(C levels. Knockdown of endogenous APP expression in cells by siRNA or inhibition of γ-secretase activity also had no effect on PrP(C levels. Overall, we did not detect any significant difference in the expression of PrP(C in any of the cell or animal-based paradigms considered, indicating that the control of cellular PrP(C levels by AICD is not as straightforward as previously suggested.

  4. Cellular IAP proteins and LUBAC differentially regulate necrosome-associated RIP1 ubiquitination

    Science.gov (United States)

    de Almagro, M C; Goncharov, T; Newton, K; Vucic, D

    2015-01-01

    Necroptosis is a caspase-independent regulated type of cell death that relies on receptor-interacting protein kinases RIP1 (receptor-interacting protein kinases 1) and RIP3. Tumor necrosis factor-α (TNFα)-stimulated assembly of the TNFR1 (TNF receptor 1)-associated signaling complex leads to the recruitment of RIP1, whose ubiquitination is mediated by the cellular inhibitors of apoptosis (c-IAPs). Translocation of RIP1 to the cytoplasm and association of RIP1 with the necrosome is believed to correlate with deubiquitination of RIP1. However, we found that RIP1 is ubiquitinated with K63 and linear polyubiquitin chains during TNFα, IAP antagonist BV6 and caspase inhibitor zVAD-fmk-induced necroptotic signaling. Furthermore, ubiquitinated RIP1 is associated with the necrosome, and RIP1 ubiquitination in the necrosome coincides with RIP3 phosphorylation. Both cellular IAPs and LUBAC (linear ubiquitin chain assembly complex) modulate RIP1 ubiquitination in IAP antagonist-treated necrotic cells, but they use different mechanisms. c-IAP1 regulates RIP1 recruitment to the necrosome without directly affecting RIP1 ubiquitination, whereas HOIP and HOIL1 mediate linear ubiquitination of RIP1 in the necrosome, but are not essential for necrosome formation. Knockdown of the E3 ligase c-IAP1 decreased RIP1 ubiquitination, necrosome assembly and necroptosis induced by TNFα, BV6 and zVAD-fmk. c-IAP1 deficiency likely decreases necroptotic cell death through the activation of the noncanonical NF-κB pathway and consequent c-IAP2 upregulation. The ability to upregulate c-IAP2 could determine whether c-IAP1 absence will have a positive or negative impact on TNFα-induced necroptotic cell death and necrosome formation. Collectively, these results reveal unexpected complexity of the roles of IAP proteins, IAP antagonists and LUBAC in the regulation of necrosome assembly. PMID:26111062

  5. TAp63γ demethylation regulates protein stability and cellular distribution during neural stem cell differentiation.

    Directory of Open Access Journals (Sweden)

    Maria B Fonseca

    Full Text Available p63 is a close relative of the p53 tumor suppressor and transcription factor that modulates cell fate. The full-length isoform of p63, containing a transactivation (TA domain (TAp63 is an essential proapoptotic protein in neural development. The role of p63 in epithelial development is also well established; however, its precise function during neural differentiation remains largely controversial. Recently, it has been demonstrated that several conserved elements of apoptosis are also integral components of cellular differentiation; p53 directly interacts with key regulators of neurogenesis. The aim of this study was to evaluate the role of p63 during mouse neural stem cell (NSC differentiation and test whether the histone H3 lysine 27-specific demethylase JMJD3 interacts with p63 to redirect NSCs to neurogenesis. Our results showed that JMJD3 and TAp63γ are coordinately regulated to establish neural-specific gene expression programs in NSCs undergoing differentiation. JMJD3 overexpression increased TAp63γ levels in a demethylase activity-dependent manner. Importantly, overexpression of TAp63γ increased β-III tubulin whereas downregulation of TAp63γ by specific p63 siRNA decreased β-III tubulin. Immunoprecipitation assays demonstrated direct interaction between TAp63γ and JMJD3, and modulation of TAp63γ methylation status by JMJD3-demethylase activity. Importantly, the demethylase activity of JMJD3 influenced TAp63γ protein stabilization and cellular distribution, as well as TAp63γ-regulated neurogenesis. These findings clarify the role of p63 in adult neural progenitor cells and reveal TAp63γ as a direct target for JMJD3-mediated neuronal commitment.

  6. Early vertebrate origin and diversification of small transmembrane regulators of cellular ion transport.

    Science.gov (United States)

    Pirkmajer, Sergej; Kirchner, Henriette; Lundell, Leonidas S; Zelenin, Pavel V; Zierath, Juleen R; Makarova, Kira S; Wolf, Yuri I; Chibalin, Alexander V

    2017-07-15

    Small transmembrane proteins such as FXYDs, which interact with Na(+) ,K(+) -ATPase, and the micropeptides that interact with sarco/endoplasmic reticulum Ca(2+) -ATPase play fundamental roles in regulation of ion transport in vertebrates. Uncertain evolutionary origins and phylogenetic relationships among these regulators of ion transport have led to inconsistencies in their classification across vertebrate species, thus hampering comparative studies of their functions. We discovered the first FXYD homologue in sea lamprey, a basal jawless vertebrate, which suggests small transmembrane regulators of ion transport emerged early in the vertebrate lineage. We also identified 13 gene subfamilies of FXYDs and propose a revised, phylogeny-based FXYD classification that is consistent across vertebrate species. These findings provide an improved framework for investigating physiological and pathophysiological functions of small transmembrane regulators of ion transport. Small transmembrane proteins are important for regulation of cellular ion transport. The most prominent among these are members of the FXYD family (FXYD1-12), which regulate Na(+) ,K(+) -ATPase, and phospholamban, sarcolipin, myoregulin and DWORF, which regulate the sarco/endoplasmic reticulum Ca(2+) -ATPase (SERCA). FXYDs and regulators of SERCA are present in fishes, as well as terrestrial vertebrates; however, their evolutionary origins and phylogenetic relationships are obscure, thus hampering comparative physiological studies. Here we discovered that sea lamprey (Petromyzon marinus), a representative of extant jawless vertebrates (Cyclostomata), expresses an FXYD homologue, which strongly suggests that FXYDs predate the emergence of fishes and other jawed vertebrates (Gnathostomata). Using a combination of sequence-based phylogenetic analysis and conservation of local chromosome context, we determined that FXYDs markedly diversified in the lineages leading to cartilaginous fishes (Chondrichthyes) and

  7. Cellular volume regulation by anoctamin 6: Ca²⁺, phospholipase A2 and osmosensing.

    Science.gov (United States)

    Sirianant, Lalida; Ousingsawat, Jiraporn; Wanitchakool, Podchanart; Schreiber, Rainer; Kunzelmann, Karl

    2016-02-01

    During cell swelling, Cl(-) channels are activated to lower intracellular Cl(-) concentrations and to reduce cell volume, a process termed regulatory volume decrease (RVD). We show that anoctamin 6 (ANO6; TMEM16F) produces volume-regulated anion currents and controls cell volume in four unrelated cell types. Volume regulation is compromised in freshly isolated intestinal epithelial cells from Ano6-/- mice and also in lymphocytes from a patient lacking expression of ANO6. Ca(2+) influx is activated and thus ANO6 is stimulated during cell swelling by local Ca(2+) increase probably in functional nanodomains near the plasma membrane. This leads to stimulation of phospholipase A2 (PLA2) and generation of plasma membrane lysophospholipids, which activates ANO6. Direct application of lysophospholipids also activates an anion current that is inhibited by typical ANO6 blocker. An increase in intracellular Ca(2+) supports activation of ANO6, but is not required when PLA2 is fully activated, while re-addition of arachidonic acid completely blocked ANO6. Moreover, ANO6 is activated by low intracellular Cl(-) concentrations and may therefore operate as a cellular osmosensor. High intracellular Cl(-) concentration inhibits ANO6 and activation by PLA2. Taken together, ANO6 supports volume regulation and volume activation of anion currents by action as a Cl(-) channel or by scrambling membrane phospholipids. Thereby, it may support the function of LRRC8 proteins.

  8. BICD2, dynactin, and LIS1 cooperate in regulating dynein recruitment to cellular structures

    Science.gov (United States)

    Splinter, Daniël; Razafsky, David S.; Schlager, Max A.; Serra-Marques, Andrea; Grigoriev, Ilya; Demmers, Jeroen; Keijzer, Nanda; Jiang, Kai; Poser, Ina; Hyman, Anthony A.; Hoogenraad, Casper C.; King, Stephen J.; Akhmanova, Anna

    2012-01-01

    Cytoplasmic dynein is the major microtubule minus-end–directed cellular motor. Most dynein activities require dynactin, but the mechanisms regulating cargo-dependent dynein–dynactin interaction are poorly understood. In this study, we focus on dynein–dynactin recruitment to cargo by the conserved motor adaptor Bicaudal D2 (BICD2). We show that dynein and dynactin depend on each other for BICD2-mediated targeting to cargo and that BICD2 N-terminus (BICD2-N) strongly promotes stable interaction between dynein and dynactin both in vitro and in vivo. Direct visualization of dynein in live cells indicates that by itself the triple BICD2-N–dynein–dynactin complex is unable to interact with either cargo or microtubules. However, tethering of BICD2-N to different membranes promotes their microtubule minus-end–directed motility. We further show that LIS1 is required for dynein-mediated transport induced by membrane tethering of BICD2-N and that LIS1 contributes to dynein accumulation at microtubule plus ends and BICD2-positive cellular structures. Our results demonstrate that dynein recruitment to cargo requires concerted action of multiple dynein cofactors. PMID:22956769

  9. Pyruvate kinase is a dosage-dependent regulator of cellular amino acid homeostasis

    Science.gov (United States)

    Grüning, Nana-Maria; Feichtinger, René; Krüger, Antje; Wamelink, Mirjam; Lehrach, Hans; Tate, Stephen; Neureiter, Daniel; Kofler, Barbara

    2012-01-01

    The glycolytic enzyme pyruvate kinase (PK) is required for cancer development, and has been implicated in the metabolic transition from oxidative to fermentative metabolism, the Warburg effect. However, the global metabolic response that follows changes in PK activity is not yet fully understood. Using shotgun proteomics, we identified 31 yeast proteins that were regulated in a PK-dependent manner. Selective reaction monitoring confirmed that their expression was dependent on PK isoform, level and activity. Most of the PK targets were amino acid metabolizing enzymes or factors of protein translation, indicating that PK plays a global regulatory role in biosynthethic amino acid metabolism. Indeed, we found strongly altered amino acid profiles when PK levels were changed. Low PK levels increased the cellular glutamine and glutamate concentrations, but decreased the levels of seven amino acids including serine and histidine. To test for evolutionary conservation of this PK function, we quantified orthologues of the identified PK targets in thyroid follicular adenoma, a tumor characterized by high PK levels and low respiratory activity. Aminopeptidase AAP-1 and serine hydroxymethyltransferase SHMT1 both showed PKM2- concentration dependence, and were upregulated in the tumor. Thus, PK expression levels and activity were important for maintaining cellular amino acid homeostasis. Mediating between energy production, ROS clearance and amino acid biosynthesis, PK thus plays a central regulatory role in the metabolism of proliferating cells. PMID:23154538

  10. Ionizing Radiation Induces Cellular Senescence of Articular Chondrocytes via Negative Regulation of SIRT1 by p38 Kinase

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Eun Hee; Hwang, Sang Gu [Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of)

    2009-05-15

    Senescent cells exhibit irreversible growth arrest, large flat morphology, and up-regulated senescence-associated {beta}-galactosidase activity at pH 6.0. Several conditions, including oncogenic stress, oxidative stress, and DNA damage are associated with cellular senescence. Massive acute DNA double-strand breaks occurring as a result of mechanical and chemical stress can be repaired, but some DNA damage persists, eventually triggering premature senescence. Since ionizing radiation directly induces DBS, it is possible that cellular senescence is activated under these conditions. The biological events in chondrocytes following irradiation are poorly understood, and limited information is available on the molecular signal transduction mechanisms of cellular senescence at present. In this study, we identify SIRT1 as a target molecule of p38 kinase and demonstrate that the interactions between p38 kinase and SIRT1 protein play an important role in the regulation of cellular senescence in response to IR.

  11. BMP2 Regulation of CXCL12 Cellular, Temporal, and Spatial Expression is Essential During Fracture Repair.

    Science.gov (United States)

    Myers, Timothy J; Longobardi, Lara; Willcockson, Helen; Temple, Joseph D; Tagliafierro, Lidia; Ye, Ping; Li, Tieshi; Esposito, Alessandra; Moats-Staats, Billie M; Spagnoli, Anna

    2015-11-01

    -reaching implications for understanding mechanisms regulating the selective recruitment of distinct cells into the repairing niches and the development of novel pharmacological (by targeting BMP2/CXCL12) and cellular (MSCs, endosteal cells) interventions to promote fracture healing.

  12. Lysophosphatidic acid receptor-5 negatively regulates cellular responses in mouse fibroblast 3T3 cells

    Energy Technology Data Exchange (ETDEWEB)

    Dong, Yan; Hirane, Miku; Araki, Mutsumi [Division of Cancer Biology and Bioinformatics, Department of Life Science, Faculty of Science and Engineering, Kinki University, 3-4-1, Kowakae, Higashiosaka, Osaka 577-8502 (Japan); Fukushima, Nobuyuki [Division of Molecular Neurobiology, Department of Life Science, Faculty of Science and Engineering, Kinki University, 3-4-1, Kowakae, Higashiosaka, Osaka 577-8502 (Japan); Tsujiuchi, Toshifumi, E-mail: ttujiuch@life.kindai.ac.jp [Division of Cancer Biology and Bioinformatics, Department of Life Science, Faculty of Science and Engineering, Kinki University, 3-4-1, Kowakae, Higashiosaka, Osaka 577-8502 (Japan)

    2014-04-04

    Highlights: • LPA{sub 5} inhibits the cell growth and motile activities of 3T3 cells. • LPA{sub 5} suppresses the cell motile activities stimulated by hydrogen peroxide in 3T3 cells. • Enhancement of LPA{sub 5} on the cell motile activities inhibited by LPA{sub 1} in 3T3 cells. • The expression and activation of Mmp-9 were inhibited by LPA{sub 5} in 3T3 cells. • LPA signaling via LPA{sub 5} acts as a negative regulator of cellular responses in 3T3 cells. - Abstract: Lysophosphatidic acid (LPA) signaling via G protein-coupled LPA receptors (LPA{sub 1}–LPA{sub 6}) mediates a variety of biological functions, including cell migration. Recently, we have reported that LPA{sub 1} inhibited the cell motile activities of mouse fibroblast 3T3 cells. In the present study, to evaluate a role of LPA{sub 5} in cellular responses, Lpar5 knockdown (3T3-L5) cells were generated from 3T3 cells. In cell proliferation assays, LPA markedly stimulated the cell proliferation activities of 3T3-L5 cells, compared with control cells. In cell motility assays with Cell Culture Inserts, the cell motile activities of 3T3-L5 cells were significantly higher than those of control cells. The activity levels of matrix metalloproteinases (MMPs) were measured by gelatin zymography. 3T3-L5 cells stimulated the activation of Mmp-2, correlating with the expression levels of Mmp-2 gene. Moreover, to assess the co-effects of LPA{sub 1} and LPA{sub 5} on cell motile activities, Lpar5 knockdown (3T3a1-L5) cells were also established from Lpar1 over-expressing (3T3a1) cells. 3T3a1-L5 cells increased the cell motile activities of 3T3a1 cells, while the cell motile activities of 3T3a1 cells were significantly lower than those of control cells. These results suggest that LPA{sub 5} may act as a negative regulator of cellular responses in mouse fibroblast 3T3 cells, similar to the case for LPA{sub 1}.

  13. 9 CFR 83.4 - VHS-regulated fish and VHS-regulated areas.

    Science.gov (United States)

    2010-01-01

    ... been isolated in cell culture or other assay determined by the Administrator to be adequate to detect... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false VHS-regulated fish and VHS-regulated areas. 83.4 Section 83.4 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE...

  14. Immediate-Early (IE) gene regulation of cytomegalovirus: IE1- and pp71-mediated viral strategies against cellular defenses.

    Science.gov (United States)

    Torres, Lilith; Tang, Qiyi

    2014-12-01

    Three crucial hurdles hinder studies on human cytomegalovirus (HCMV): strict species specificity, differences between in vivo and in vitro infection, and the complexity of gene regulation. Ever since the sequencing of the whole genome was first accomplished, functional studies on individual genes have been the mainstream in the CMV field. Gene regulation has therefore been elucidated in a more detailed fashion. However, viral gene regulation is largely controlled by both cellular and viral components. In other words, viral gene expression is determined by the virus-host interaction. Generally, cells respond to viral infection in a defensive pattern; at the same time, viruses try to counteract the cellular defense or else hide in the host (latency). Viruses evolve effective strategies against cellular defense in order to achieve replicative success. Whether or not they are successful, cellular defenses remain in the whole viral replication cycle: entry, immediate-early (IE) gene expression, early gene expression, DNA replication, late gene expression, and viral egress. Many viral strategies against cellular defense, and which occur in the immediate-early time of viral infection, have been documented. In this review, we will summarize the documented biological functions of IE1 and pp71 proteins, especially with regard to how they counteract cellular intrinsic defenses.

  15. Immediate–Early (IE) gene regulation of cytomegalovirus: IE1- and pp71-mediated viral strategies against cellular defenses

    Science.gov (United States)

    Torres, Lilith; Tang, Qiyi

    2015-01-01

    Three crucial hurdles hinder studies on human cytomegalovirus (HCMV): strict species specificity, differences between in vivo and in vitro infection, and the complexity of gene regulation. Ever since the sequencing of the whole genome was first accomplished, functional studies on individual genes have been the mainstream in the CMV field. Gene regulation has therefore been elucidated in a more detailed fashion. However, viral gene regulation is largely controlled by both cellular and viral components. In other words, viral gene expression is determined by the virus–host interaction. Generally, cells respond to viral infection in a defensive pattern; at the same time, viruses try to counteract the cellular defense or else hide in the host (latency). Viruses evolve effective strategies against cellular defense in order to achieve replicative success. Whether or not they are successful, cellular defenses remain in the whole viral replication cycle: entry, immediate–early (IE) gene expression, early gene expression, DNA replication, late gene expression, and viral egress. Many viral strategies against cellular defense, and which occur in the immediate–early time of viral infection, have been documented. In this review, we will summarize the documented biological functions of IE1 and pp71 proteins, especially with regard to how they counteract cellular intrinsic defenses. PMID:25501994

  16. Immediate–Early(IE) gene regulation of cytomegalovirus:IE1-and pp71-mediated viral strategies against cellular defenses

    Institute of Scientific and Technical Information of China (English)

    Lilith; Torres; Qiyi; Tang

    2014-01-01

    Three crucial hurdles hinder studies on human cytomegalovirus(HCMV): strict species specificity, differences between in vivo and in vitro infection, and the complexity of gene regulation. Ever since the sequencing of the whole genome was first accomplished, functional studies on individual genes have been the mainstream in the CMV field. Gene regulation has therefore been elucidated in a more detailed fashion. However, viral gene regulation is largely controlled by both cellular and viral components. In other words, viral gene expression is determined by the virus–host interaction. Generally, cells respond to viral infection in a defensive pattern; at the same time, viruses try to counteract the cellular defense or else hide in the host(latency). Viruses evolve effective strategies against cellular defense in order to achieve replicative success. Whether or not they are successful, cellular defenses remain in the whole viral replication cycle: entry, immediate–early(IE) gene expression, early gene expression, DNA replication, late gene expression, and viral egress. Many viral strategies against cellular defense, and which occur in the immediate–early time of viral infection, have been documented. In this review, we will summarize the documented biological functions of IE1 and pp71 proteins, especially with regard to how they counteract cellular intrinsic defenses.

  17. ECM Signaling Regulates Collective Cellular Dynamics to Control Pancreas Branching Morphogenesis.

    Science.gov (United States)

    Shih, Hung Ping; Panlasigui, Devin; Cirulli, Vincenzo; Sander, Maike

    2016-01-12

    During pancreas development, epithelial buds undergo branching morphogenesis to form an exocrine and endocrine gland. Proper morphogenesis is necessary for correct lineage allocation of pancreatic progenitors; however, the cellular events underlying pancreas morphogenesis are unknown. Here, we employed time-lapse microscopy and fluorescent labeling of cells to analyze cell behaviors associated with pancreas morphogenesis. We observed that outer bud cells adjacent to the basement membrane are pleomorphic and rearrange frequently; additionally, they largely remain in the outer cell compartment even after mitosis. These cell behaviors and pancreas branching depend on cell contacts with the basement membrane, which induce actomyosin cytoskeleton remodeling via integrin-mediated activation of FAK/Src signaling. We show that integrin signaling reduces E-cadherin-mediated cell-cell adhesion in outer cells and provide genetic evidence that this regulation is necessary for initiation of branching. Our study suggests that regulation of cell motility and adhesion by local niche cues initiates pancreas branching morphogenesis. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  18. ECM Signaling Regulates Collective Cellular Dynamics to Control Pancreas Branching Morphogenesis

    Directory of Open Access Journals (Sweden)

    Hung Ping Shih

    2016-01-01

    Full Text Available During pancreas development, epithelial buds undergo branching morphogenesis to form an exocrine and endocrine gland. Proper morphogenesis is necessary for correct lineage allocation of pancreatic progenitors; however, the cellular events underlying pancreas morphogenesis are unknown. Here, we employed time-lapse microscopy and fluorescent labeling of cells to analyze cell behaviors associated with pancreas morphogenesis. We observed that outer bud cells adjacent to the basement membrane are pleomorphic and rearrange frequently; additionally, they largely remain in the outer cell compartment even after mitosis. These cell behaviors and pancreas branching depend on cell contacts with the basement membrane, which induce actomyosin cytoskeleton remodeling via integrin-mediated activation of FAK/Src signaling. We show that integrin signaling reduces E-cadherin-mediated cell-cell adhesion in outer cells and provide genetic evidence that this regulation is necessary for initiation of branching. Our study suggests that regulation of cell motility and adhesion by local niche cues initiates pancreas branching morphogenesis.

  19. Cellular resolution models for even skipped regulation in the entire Drosophila embryo

    Science.gov (United States)

    Ilsley, Garth R; Fisher, Jasmin; Apweiler, Rolf; DePace, Angela H; Luscombe, Nicholas M

    2013-01-01

    Transcriptional control ensures genes are expressed in the right amounts at the correct times and locations. Understanding quantitatively how regulatory systems convert input signals to appropriate outputs remains a challenge. For the first time, we successfully model even skipped (eve) stripes 2 and 3+7 across the entire fly embryo at cellular resolution. A straightforward statistical relationship explains how transcription factor (TF) concentrations define eve’s complex spatial expression, without the need for pairwise interactions or cross-regulatory dynamics. Simulating thousands of TF combinations, we recover known regulators and suggest new candidates. Finally, we accurately predict the intricate effects of perturbations including TF mutations and misexpression. Our approach imposes minimal assumptions about regulatory function; instead we infer underlying mechanisms from models that best fit the data, like the lack of TF-specific thresholds and the positional value of homotypic interactions. Our study provides a general and quantitative method for elucidating the regulation of diverse biological systems. DOI: http://dx.doi.org/10.7554/eLife.00522.001 PMID:23930223

  20. A conformational change within the WAVE2 complex regulates its degradation following cellular activation

    Science.gov (United States)

    Joseph, Noah; Biber, Guy; Fried, Sophia; Reicher, Barak; Levy, Omer; Sabag, Batel; Noy, Elad; Barda-Saad, Mira

    2017-01-01

    WASp family Verprolin-homologous protein-2 (WAVE2), a member of the Wiskott-Aldrich syndrome protein (WASp) family of actin nucleation promoting factors, is a central regulator of actin cytoskeleton polymerization and dynamics. Multiple signaling pathways operate via WAVE2 to promote the actin-nucleating activity of the actin-related protein 2/3 (Arp2/3) complex. WAVE2 exists as a part of a pentameric protein complex known as the WAVE regulatory complex (WRC), which is unstable in the absence of its individual proteins. While the involvement of WAVE2 in actin polymerization has been well documented, its negative regulation mechanism is poorly characterized to date. Here, we demonstrate that WAVE2 undergoes ubiquitylation in a T-cell activation dependent manner, followed by proteasomal degradation. The WAVE2 ubiquitylation site was mapped to lysine 45, located at the N-terminus where WAVE2 binds to the WRC. Using Förster resonance energy transfer (FRET), we reveal that the autoinhibitory conformation of the WRC maintains the stability of WAVE2 in resting cells; the release of autoinhibition following T-cell activation facilitates the exposure of WAVE2 to ubiquitylation, leading to its degradation. The dynamic conformational structures of WAVE2 during cellular activation dictate its degradation. PMID:28332566

  1. Lipolysis - a highly regulated multi-enzyme complex mediates the catabolism of cellular fat stores.

    Science.gov (United States)

    Lass, Achim; Zimmermann, Robert; Oberer, Monika; Zechner, Rudolf

    2011-01-01

    Lipolysis is the biochemical pathway responsible for the catabolism of triacylglycerol (TAG) stored in cellular lipid droplets. The hydrolytic cleavage of TAG generates non-esterified fatty acids, which are subsequently used as energy substrates, essential precursors for lipid and membrane synthesis, or mediators in cell signaling processes. Consistent with its central importance in lipid and energy homeostasis, lipolysis occurs in essentially all tissues and cell types, it is most abundant, however, in white and brown adipose tissue. Over the last 5years, important enzymes and regulatory protein factors involved in lipolysis have been identified. These include an essential TAG hydrolase named adipose triglyceride lipase (ATGL) [annotated as patatin-like phospholipase domain-containing protein A2], the ATGL activator comparative gene identification-58 [annotated as α/β hydrolase containing protein 5], and the ATGL inhibitor G0/G1 switch gene 2. Together with the established hormone-sensitive lipase [annotated as lipase E] and monoglyceride lipase, these proteins constitute the basic "lipolytic machinery". Additionally, a large number of hormonal signaling pathways and lipid droplet-associated protein factors regulate substrate access and the activity of the "lipolysome". This review summarizes the current knowledge concerning the enzymes and regulatory processes governing lipolysis of fat stores in adipose and non-adipose tissues. Special emphasis will be given to ATGL, its regulation, and physiological function. Copyright © 2010 Elsevier Ltd. All rights reserved.

  2. Lipolysis – A highly regulated multi-enzyme complex mediates the catabolism of cellular fat stores

    Science.gov (United States)

    Lass, Achim; Zimmermann, Robert; Oberer, Monika; Zechner, Rudolf

    2011-01-01

    Summary Lipolysis is the biochemical pathway responsible for the catabolism of triacylglycerol (TAG) stored in cellular lipid droplets. The hydrolytic cleavage of TAG generates non-esterified fatty acids, which are subsequently used as energy substrates, essential precursors for lipid and membrane synthesis, or mediators in cell signaling processes. Consistent with its central importance in lipid and energy homeostasis, lipolysis occurs in essentially all tissues and cell types, it is most abundant, however, in white and brown adipose tissue. Over the last 5 years, important enzymes and regulatory protein factors involved in lipolysis have been identified. These include an essential TAG hydrolase named adipose triglyceride lipase (ATGL) [annotated as patatin-like phospholipase domain-containing protein A2], the ATGL activator comparative gene identification-58 [annotated as α/β hydrolase containing protein 5], and the ATGL inhibitor G0/G1 switch gene 2. Together with the established hormone-sensitive lipase [annotated as lipase E] and monoglyceride lipase, these proteins constitute the basic “lipolytic machinery”. Additionally, a large number of hormonal signaling pathways and lipid droplet-associated protein factors regulate substrate access and the activity of the “lipolysome”. This review summarizes the current knowledge concerning the enzymes and regulatory processes governing lipolysis of fat stores in adipose and non-adipose tissues. Special emphasis will be given to ATGL, its regulation, and physiological function. PMID:21087632

  3. Cellular chloride and bicarbonate retention alters intracellular pH regulation in Cftr KO crypt epithelium.

    Science.gov (United States)

    Walker, Nancy M; Liu, Jinghua; Stein, Sydney R; Stefanski, Casey D; Strubberg, Ashlee M; Clarke, Lane L

    2016-01-15

    Cystic fibrosis (CF) is caused by mutations in the CF transmembrane conductance regulator (CFTR), an anion channel providing a major pathway for Cl(-) and HCO3 (-) efflux across the apical membrane of the epithelium. In the intestine, CF manifests as obstructive syndromes, dysbiosis, inflammation, and an increased risk for gastrointestinal cancer. Cftr knockout (KO) mice recapitulate CF intestinal disease, including intestinal hyperproliferation. Previous studies using Cftr KO intestinal organoids (enteroids) indicate that crypt epithelium maintains an alkaline intracellular pH (pHi). We hypothesized that Cftr has a cell-autonomous role in downregulating pHi that is incompletely compensated by acid-base regulation in its absence. Here, 2',7'-bis(2-carboxyethyl)-5(6)-carboxyfluorescein microfluorimetry of enteroids showed that Cftr KO crypt epithelium sustains an alkaline pHi and resistance to cell acidification relative to wild-type. Quantitative real-time PCR revealed that Cftr KO enteroids exhibit downregulated transcription of base (HCO3 (-))-loading proteins and upregulation of the basolateral membrane HCO3 (-)-unloader anion exchanger 2 (Ae2). Although Cftr KO crypt epithelium had increased Ae2 expression and Ae2-mediated Cl(-)/HCO3 (-) exchange with maximized gradients, it also had increased intracellular Cl(-) concentration relative to wild-type. Pharmacological reduction of intracellular Cl(-) concentration in Cftr KO crypt epithelium normalized pHi, which was largely Ae2-dependent. We conclude that Cftr KO crypt epithelium maintains an alkaline pHi as a consequence of losing both Cl(-) and HCO3 (-) efflux, which impairs pHi regulation by Ae2. Retention of Cl(-) and an alkaline pHi in crypt epithelium may alter several cellular processes in the proliferative compartment of Cftr KO intestine.

  4. Redox regulation of human OGG1 activity in response to cellular oxidative stress.

    Science.gov (United States)

    Bravard, Anne; Vacher, Monique; Gouget, Barbara; Coutant, Alexandre; de Boisferon, Florence Hillairet; Marsin, Stéphanie; Chevillard, Sylvie; Radicella, J Pablo

    2006-10-01

    8-Oxoguanine (8-oxoG), a common and mutagenic form of oxidized guanine in DNA, is eliminated mainly through base excision repair. In human cells its repair is initiated by human OGG1 (hOGG1), an 8-oxoG DNA glycosylase. We investigated the effects of an acute cadmium exposure of human lymphoblastoid cells on the activity of hOGG1. We show that coinciding with alteration of the redox cellular status, the 8-oxoG DNA glycosylase activity of hOGG1 was nearly completely inhibited. However, the hOGG1 activity returned to normal levels once the redox cellular status was normalized. In vitro, the activity of purified hOGG1 was abolished by cadmium and could not be recovered by EDTA. In cells, however, the reversible inactivation of OGG1 activity by cadmium was strictly associated with reversible oxidation of the protein. Moreover, the 8-oxoG DNA glycosylase activity of purified OGG1 and that from crude extracts were modulated by cysteine-modifying agents. Oxidation of OGG1 by the thiol oxidant diamide led to inhibition of the activity and a protein migration pattern similar to that seen in cadmium-treated cells. These results suggest that cadmium inhibits hOGG1 activity mainly by indirect oxidation of critical cysteine residues and that excretion of the metal from the cells leads to normalization of the redox cell status and restoration of an active hOGG1. The results presented here unveil a novel redox-dependent mechanism for the regulation of OGG1 activity.

  5. Cellular Basis of Pineal Gland Development: Emerging Role of Microglia as Phenotype Regulator.

    Science.gov (United States)

    Ibañez Rodriguez, María P; Noctor, Stephen C; Muñoz, Estela M

    2016-01-01

    The adult pineal gland is composed of pinealocytes, astrocytes, microglia, and other interstitial cells that have been described in detail. However, factors that contribute to pineal development have not been fully elucidated, nor have pineal cell lineages been well characterized. We applied systematic double, triple and quadruple labeling of cell-specific markers on prenatal, postnatal and mature rat pineal gland tissue combined with confocal microscopy to provide a comprehensive view of the cellular dynamics and cell lineages that contribute to pineal gland development. The pineal gland begins as an evagination of neuroepithelium in the roof of the third ventricle. The pineal primordium initially consists of radially aligned Pax6+ precursor cells that express vimentin and divide at the ventricular lumen. After the tubular neuroepithelium fuses, the distribution of Pax6+ cells transitions to include rosette-like structures and later, dispersed cells. In the developing gland all dividing cells express Pax6, indicating that Pax6+ precursor cells generate pinealocytes and some interstitial cells. The density of Pax6+ cells decreases across pineal development as a result of cellular differentiation and microglial phagocytosis, but Pax6+ cells remain in the adult gland as a distinct population. Microglial colonization begins after pineal recess formation. Microglial phagocytosis of Pax6+ cells is not common at early stages but increases as microglia colonize the gland. In the postnatal gland microglia affiliate with Tuj1+ nerve fibers, IB4+ blood vessels, and Pax6+ cells. We demonstrate that microglia engulf Pax6+ cells, nerve fibers, and blood vessel-related elements, but not pinealocytes. We conclude that microglia play a role in pineal gland formation and homeostasis by regulating the precursor cell population, remodeling blood vessels and pruning sympathetic nerve fibers.

  6. PI3K/AKT and ERK regulate retinoic acid-induced neuroblastoma cellular differentiation

    Energy Technology Data Exchange (ETDEWEB)

    Qiao, Jingbo [Department of Pediatric Surgery, Vanderbilt University Medical Center, Nashville, TN 37232 (United States); 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, Lan; Josifi, Erlena; Tiao, Joshua R. [Department of Pediatric Surgery, Vanderbilt University Medical Center, Nashville, TN 37232 (United States); 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)

    2012-08-03

    Highlights: Black-Right-Pointing-Pointer Retinoic acid (RA) induces neuroblastoma cells differentiation, which is accompanied by G0/G1 cell cycle arrest. Black-Right-Pointing-Pointer RA resulted in neuroblastoma cell survival and inhibition of DNA fragmentation; this is regulated by PI3K pathway. Black-Right-Pointing-Pointer RA activates PI3K and ERK1/2 pathway; PI3K pathway mediates RA-induced neuroblastoma cell differentiation. Black-Right-Pointing-Pointer Upregulation of p21 is necessary for RA-induced neuroblastoma cell differentiation. -- Abstract: Neuroblastoma, the most common extra-cranial solid tumor in infants and children, is characterized by a high rate of spontaneous remissions in infancy. Retinoic acid (RA) has been known to induce neuroblastoma differentiation; however, the molecular mechanisms and signaling pathways that are responsible for RA-mediated neuroblastoma cell differentiation remain unclear. Here, we sought to determine the cell signaling processes involved in RA-induced cellular differentiation. Upon RA administration, human neuroblastoma cell lines, SK-N-SH and BE(2)-C, demonstrated neurite extensions, which is an indicator of neuronal cell differentiation. Moreover, cell cycle arrest occurred in G1/G0 phase. The protein levels of cyclin-dependent kinase inhibitors, p21 and p27{sup Kip}, which inhibit cell proliferation by blocking cell cycle progression at G1/S phase, increased after RA treatment. Interestingly, RA promoted cell survival during the differentiation process, hence suggesting a potential mechanism for neuroblastoma resistance to RA therapy. Importantly, we found that the PI3K/AKT pathway is required for RA-induced neuroblastoma cell differentiation. Our results elucidated the molecular mechanism of RA-induced neuroblastoma cellular differentiation, which may be important for developing novel therapeutic strategy against poorly differentiated neuroblastoma.

  7. Urban mobility regulation in metropolitan area of Mendoza

    Directory of Open Access Journals (Sweden)

    Lía Martínez

    2016-11-01

    Full Text Available Achieving the paradigm of sustainable urban mobility requires institutional capacities, appropriate policies and a regulatory framework that contains them. This work aims to contribute to the knowledge of the regulation of urban mobility in the metropolitan area of Mendoza. To this end, the current mobility regulations are assessed through indicators that are classified into three key areas: institutional and political organization, urban system and financial setup. The purpose is to account for the existence, or not, of regulatory capacities contained in the paradigm of sustainable mobility. Among the results, the absence of a policy of sustainable urban mobility is noteworthy, as well as the lack of sectorial coordination. Also of note is the absence of coordination between the urban planning system and the public transport provision. Lastly, in the financial sector, the results point to a promotion of sustainable transport modes but without such an explicit purpose.

  8. The anticancer plant triterpenoid, avicin D, regulates glucocorticoid receptor signaling: implications for cellular metabolism.

    Directory of Open Access Journals (Sweden)

    Valsala Haridas

    Full Text Available Avicins, a family of apoptotic triterpene electrophiles, are known to regulate cellular metabolism and energy homeostasis, by targeting the mitochondria. Having evolved from "ancient hopanoids," avicins bear a structural resemblance with glucocorticoids (GCs, which are the endogenous regulators of metabolism and energy balance. These structural and functional similarities prompted us to compare the mode of action of avicin D with dexamethasone (Dex, a prototypical GC. Using cold competition assay, we show that Avicin D competes with Dex for binding to the GC receptor (GR, leading to its nuclear translocation. In contrast to Dex, avicin-induced nuclear translocation of GR does not result in transcriptional activation of GC-dependent genes. Instead we observe a decrease in the expression of GC-dependent metabolic proteins such as PEPCK and FASN. However, like Dex, avicin D treatment does induce a transrepressive effect on the pro-inflammatory transcription factor NF-κB. While avicin's ability to inhibit NF-κB and its downstream targets appear to be GR-dependent, its pro-apoptotic effects were independent of GR expression. Using various deletion mutants of GR, we demonstrate the requirement of both the DNA and ligand binding domains of GR in mediating avicin D's transrepressive effects. Modeling of avicin-GR interaction revealed that avicin molecule binds only to the antagonist confirmation of GR. These findings suggest that avicin D has properties of being a selective GR modulator that separates transactivation from transrepression. Since the gene-activating properties of GR are mainly linked to its metabolic effects, and the negative interference with the activity of transcription factors to its anti-inflammatory and immune suppressive effects, the identification of such a dissociated GR ligand could have great potential for therapeutic use.

  9. NR4A2 is regulated by gastrin and influences cellular responses of gastric adenocarcinoma cells.

    Directory of Open Access Journals (Sweden)

    Kristine Misund

    Full Text Available The peptide hormone gastrin is known to play a role in differentiation, growth and apoptosis of cells in the gastric mucosa. In this study we demonstrate that gastrin induces Nuclear Receptor 4A2 (NR4A2 expression in the adenocarcinoma cell lines AR42J and AGS-GR, which both possess the gastrin/CCK2 receptor. In vivo, NR4A2 is strongly expressed in the gastrin responsive neuroendocrine ECL cells in normal mucosa, whereas gastric adenocarcinoma tissue reveals a more diffuse and variable expression in tumor cells. We show that NR4A2 is a primary early transient gastrin induced gene in adenocarcinoma cell lines, and that NR4A2 expression is negatively regulated by inducible cAMP early repressor (ICER and zinc finger protein 36, C3H1 type-like 1 (Zfp36l1, suggesting that these gastrin regulated proteins exert a negative feedback control of NR4A2 activated responses. FRAP analyses indicate that gastrin also modifies the nucleus-cytosol shuttling of NR4A2, with more NR4A2 localized to cytoplasm upon gastrin treatment. Knock-down experiments with siRNA targeting NR4A2 increase migration of gastrin treated adenocarcinoma AGS-GR cells, while ectopically expressed NR4A2 increases apoptosis and hampers gastrin induced invasion, indicating a tumor suppressor function of NR4A2. Collectively, our results uncover a role of NR4A2 in gastric adenocarcinoma cells, and suggest that both the level and the localization of NR4A2 protein are of importance regarding the cellular responses of these cells.

  10. The anticancer plant triterpenoid, avicin D, regulates glucocorticoid receptor signaling: implications for cellular metabolism.

    Science.gov (United States)

    Haridas, Valsala; Xu, Zhi-Xiang; Kitchen, Doug; Jiang, Anna; Michels, Peter; Gutterman, Jordan U

    2011-01-01

    Avicins, a family of apoptotic triterpene electrophiles, are known to regulate cellular metabolism and energy homeostasis, by targeting the mitochondria. Having evolved from "ancient hopanoids," avicins bear a structural resemblance with glucocorticoids (GCs), which are the endogenous regulators of metabolism and energy balance. These structural and functional similarities prompted us to compare the mode of action of avicin D with dexamethasone (Dex), a prototypical GC. Using cold competition assay, we show that Avicin D competes with Dex for binding to the GC receptor (GR), leading to its nuclear translocation. In contrast to Dex, avicin-induced nuclear translocation of GR does not result in transcriptional activation of GC-dependent genes. Instead we observe a decrease in the expression of GC-dependent metabolic proteins such as PEPCK and FASN. However, like Dex, avicin D treatment does induce a transrepressive effect on the pro-inflammatory transcription factor NF-κB. While avicin's ability to inhibit NF-κB and its downstream targets appear to be GR-dependent, its pro-apoptotic effects were independent of GR expression. Using various deletion mutants of GR, we demonstrate the requirement of both the DNA and ligand binding domains of GR in mediating avicin D's transrepressive effects. Modeling of avicin-GR interaction revealed that avicin molecule binds only to the antagonist confirmation of GR. These findings suggest that avicin D has properties of being a selective GR modulator that separates transactivation from transrepression. Since the gene-activating properties of GR are mainly linked to its metabolic effects, and the negative interference with the activity of transcription factors to its anti-inflammatory and immune suppressive effects, the identification of such a dissociated GR ligand could have great potential for therapeutic use.

  11. Cellular DDX3 regulates Japanese encephalitis virus replication by interacting with viral un-translated regions.

    Science.gov (United States)

    Li, Chen; Ge, Ling-ling; Li, Peng-peng; Wang, Yue; Dai, Juan-juan; Sun, Ming-xia; Huang, Li; Shen, Zhi-qiang; Hu, Xiao-chun; Ishag, Hassan; Mao, Xiang

    2014-01-20

    Japanese encephalitis virus is one of the most common causes for epidemic viral encephalitis in humans and animals. Herein we demonstrated that cellular helicase DDX3 is involved in JEV replication. DDX3 knockdown inhibits JEV replication. The helicase activity of DDX3 is crucial for JEV replication. GST-pulldown and co-immunoprecipitation experiments demonstrated that DDX3 could interact with JEV non-structural proteins 3 and 5. Co-immunoprecipitation and confocal microscopy analysis confirmed that DDX3 interacts and colocalizes with these viral proteins and viral RNA during the infection. We determined that DDX3 binds to JEV 5' and 3' un-translated regions. We used a JEV-replicon system to demonstrate that DDX3 positively regulates viral RNA translation, which might affect viral RNA replication at the late stage of virus infection. Collectively, we identified that DDX3 is necessary for JEV infection, suggesting that DDX3 might be a novel target to design new antiviral agents against JEV or other flavivirus infections.

  12. Viral and cellular SOS-regulated motor proteins: dsDNA translocation mechanisms with divergent functions.

    Science.gov (United States)

    Wolfe, Annie; Phipps, Kara; Weitao, Tao

    2014-01-01

    DNA damage attacks on bacterial cells have been known to activate the SOS response, a transcriptional response affecting chromosome replication, DNA recombination and repair, cell division and prophage induction. All these functions require double-stranded (ds) DNA translocation by ASCE hexameric motors. This review seeks to delineate the structural and functional characteristics of the SOS response and the SOS-regulated DNA translocases FtsK and RuvB with the phi29 bacteriophage packaging motor gp16 ATPase as a prototype to study bacterial motors. While gp16 ATPase, cellular FtsK and RuvB are similarly comprised of hexameric rings encircling dsDNA and functioning as ATP-driven DNA translocases, they utilize different mechanisms to accomplish separate functions, suggesting a convergent evolution of these motors. The gp16 ATPase and FtsK use a novel revolution mechanism, generating a power stroke between subunits through an entropy-DNA affinity switch and pushing dsDNA inward without rotation of DNA and the motor, whereas RuvB seems to employ a rotation mechanism that remains to be further characterized. While FtsK and RuvB perform essential tasks during the SOS response, their roles may be far more significant as SOS response is involved in antibiotic-inducible bacterial vesiculation and biofilm formation as well as the perspective of the bacteria-cancer evolutionary interaction.

  13. Identifying disease feature genes based on cellular localized gene functional modules and regulation networks

    Institute of Scientific and Technical Information of China (English)

    ZHANG Min; ZHU Jing; GUO Zheng; LI Xia; YANG Da; WANG Lei; RAO Shaoqi

    2006-01-01

    Identifying disease-relevant genes and functional modules, based on gene expression profiles and gene functional knowledge, is of high importance for studying disease mechanisms and subtyping disease phenotypes. Using gene categories of biological process and cellular component in Gene Ontology, we propose an approach to selecting functional modules enriched with differentially expressed genes, and identifying the feature functional modules of high disease discriminating abilities. Using the differentially expressed genes in each feature module as the feature genes, we reveal the relevance of the modules to the studied diseases. Using three datasets for prostate cancer, gastric cancer, and leukemia, we have demonstrated that the proposed modular approach is of high power in identifying functionally integrated feature gene subsets that are highly relevant to the disease mechanisms. Our analysis has also shown that the critical disease-relevant genes might be better recognized from the gene regulation network, which is constructed using the characterized functional modules, giving important clues to the concerted mechanisms of the modules responding to complex disease states. In addition, the proposed approach to selecting the disease-relevant genes by jointly considering the gene functional knowledge suggests a new way for precisely classifying disease samples with clear biological interpretations, which is critical for the clinical diagnosis and the elucidation of the pathogenic basis of complex diseases.

  14. CD81 is a central regulator of cellular events required for hepatitis C virus infection of human hepatocytes.

    Science.gov (United States)

    Brazzoli, Michela; Bianchi, Alessia; Filippini, Sara; Weiner, Amy; Zhu, Qing; Pizza, Mariagrazia; Crotta, Stefania

    2008-09-01

    Infection with hepatitis C virus (HCV) is still a major public health problem, and the events leading to hepatocyte infection are not yet fully understood. Combining confocal microscopy with biochemical analysis and studies of infection requirements using pharmacological inhibitors and small interfering RNAs, we show here that engagement of CD81 activates the Rho GTPase family members Rac, Rho, and Cdc42 and that the block of these signaling pathways drastically reduces HCV infectivity. Activation of Rho GTPases mediates actin-dependent relocalization of the HCV E2/CD81 complex to cell-cell contact areas where CD81 comes into contact with the tight-junction proteins occludin, ZO-1, and claudin-1, which was recently described as an HCV coreceptor. Finally, we show that CD81 engagement activates the Raf/MEK/ERK signaling cascade and that this pathway affects postentry events of the virus life cycle. In conclusion, we describe a range of cellular events that are manipulated by HCV to coordinate interactions with its multiple coreceptors and to establish productive infections and find that CD81 is a central regulator of these events.

  15. SEPTIN2 and STATHMIN Regulate CD99-Mediated Cellular Differentiation in Hodgkin's Lymphoma.

    Science.gov (United States)

    Jian, Wenjing; Zhong, Lin; Wen, Jing; Tang, Yao; Qiu, Bo; Wu, Ziqing; Yan, Jinhai; Zhou, Xinhua; Zhao, Tong

    2015-01-01

    Hodgkin's lymphoma (HL) is a lymphoid neoplasm characterized by Hodgkin's and Reed-Sternberg (H/RS) cells, which is regulated by CD99. We previously reported that CD99 downregulation led to the transformation of murine B lymphoma cells (A20) into cells with an H/RS phenotype, while CD99 upregulation induced differentiation of classical Hodgkin's lymphoma (cHL) cells (L428) into terminal B-cells. However, the molecular mechanism remains unclear. In this study, using fluorescence two-dimensional differential in-gel electrophoresis and matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS), we have analyzed the alteration of protein expression following CD99 upregulation in L428 cells as well as downregulation of mouse CD99 antigen-like 2 (mCD99L2) in A20 cells. Bioinformatics analysis showed that SEPTIN2 and STATHMIN, which are cytoskeleton proteins, were significantly differentially expressed, and chosen for further validation and functional analysis. Differential expression of SEPTIN2 was found in both models and was inversely correlated with CD99 expression. STATHMIN was identified in the A20 cell line model and its expression was positively correlated with that of CD99. Importantly, silencing of SEPTIN2 with siRNA substantially altered the cellular cytoskeleton in L428 cells. The downregulation of STATHMIN by siRNA promoted the differentiation of H/RS cells toward terminal B-cells. These results suggest that SEPTIN2-mediated cytoskeletal rearrangement and STATHMIN-mediated differentiation may contribute to changes in cell morphology and differentiation of H/RS cells with CD99 upregulation in HL.

  16. SEPTIN2 and STATHMIN Regulate CD99-Mediated Cellular Differentiation in Hodgkin's Lymphoma.

    Directory of Open Access Journals (Sweden)

    Wenjing Jian

    Full Text Available Hodgkin's lymphoma (HL is a lymphoid neoplasm characterized by Hodgkin's and Reed-Sternberg (H/RS cells, which is regulated by CD99. We previously reported that CD99 downregulation led to the transformation of murine B lymphoma cells (A20 into cells with an H/RS phenotype, while CD99 upregulation induced differentiation of classical Hodgkin's lymphoma (cHL cells (L428 into terminal B-cells. However, the molecular mechanism remains unclear. In this study, using fluorescence two-dimensional differential in-gel electrophoresis and matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS, we have analyzed the alteration of protein expression following CD99 upregulation in L428 cells as well as downregulation of mouse CD99 antigen-like 2 (mCD99L2 in A20 cells. Bioinformatics analysis showed that SEPTIN2 and STATHMIN, which are cytoskeleton proteins, were significantly differentially expressed, and chosen for further validation and functional analysis. Differential expression of SEPTIN2 was found in both models and was inversely correlated with CD99 expression. STATHMIN was identified in the A20 cell line model and its expression was positively correlated with that of CD99. Importantly, silencing of SEPTIN2 with siRNA substantially altered the cellular cytoskeleton in L428 cells. The downregulation of STATHMIN by siRNA promoted the differentiation of H/RS cells toward terminal B-cells. These results suggest that SEPTIN2-mediated cytoskeletal rearrangement and STATHMIN-mediated differentiation may contribute to changes in cell morphology and differentiation of H/RS cells with CD99 upregulation in HL.

  17. Optimal planning for cellular networks for smart metering infrastructure in rural and remote areas

    Directory of Open Access Journals (Sweden)

    Andrés Masache

    2015-07-01

    Full Text Available Smart metering is used to control, monitor and know the system status in real time; to this effect, the incorporation of smart grids primarily benefits the electrical system; similarly, the reuse of infrastructure and cellular spectrum help mitigate the time and cost of its implementation. In order to reduce traffic and saturation of cellular networks, this paper aims at determining the optimal route for information transmission analyzing the optimal routing through distances and optimal routing through traffic flow. This analysis helps determine what the optimal route is, when there is no traffic on the wireless network, or when there is prolonged traffic, and what the traffic tendencies are, that may occur by excessive information transmission of smart meters to electric distribution companies.

  18. ATR controls cellular adaptation to hypoxia through positive regulation of hypoxia-inducible factor 1 (HIF-1) expression.

    Science.gov (United States)

    Fallone, F; Britton, S; Nieto, L; Salles, B; Muller, C

    2013-09-12

    Tumor cells adaptation to severe oxygen deprivation (hypoxia) plays a major role in tumor progression. The transcription factor HIF-1 (hypoxia-inducible factor 1), whose α-subunit is stabilized under hypoxic conditions is a key component of this process. Recent studies showed that two members of the phosphoinositide 3-kinase-related kinases (PIKKs) family, ATM (ataxia telangiectasia mutated) and DNA-PK (DNA-dependent protein kinase), regulate the hypoxic-dependent accumulation of HIF-1. These proteins initiate cellular stress responses when DNA damage occurs. In addition, it has been demonstrated that extreme hypoxia induces a replicative stress resulting in regions of single-stranded DNA at stalled replication forks and the activation of ATR (ataxia telangiectasia and Rad3 related protein), another member of the PIKKs family. Here, we show that even less severe hypoxia (0.1% O2) also induces activation of ATR through replicative stress. Importantly, in using either transiently silenced ATR cells, cells expressing an inactive form of ATR or cells exposed to an ATR inhibitor (CGK733), we demonstrate that hypoxic ATR activation positively regulates the key transcription factor HIF-1 independently of the checkpoint kinase Chk1. We show that ATR kinase activity regulates HIF-1α at the translational level and we find that the elements necessary for the regulation of HIF-1α translation are located within the coding region of HIF-1α mRNA. Finally, by using three independent cellular models, we clearly show that the loss of ATR expression and/or kinase activity results in the decrease of HIF-1 DNA binding under hypoxia and consequently affects protein expression levels of two HIF-1 target genes, GLUT-1 and CAIX. Taken together, our data show a new function for ATR in cellular adaptation to hypoxia through regulation of HIF-1α translation. Our work offers new prospect for cancer therapy using ATR inhibitors with the potential to decrease cellular adaptation in hypoxic

  19. Regulation of Cellular Response Pattern to Phosphorus Ion is a New Target for the Design of Tissue-Engineered Blood Vessel.

    Science.gov (United States)

    Chen, Wen; Wang, Fangjuan; Zeng, Wen; Sun, Jun; Li, Li; Yang, Mingcan; Sun, Jiansen; Wu, Yangxiao; Zhao, Xiaohui; Zhu, Chuhong

    2015-05-01

    Regulation of cellular response pattern to phosphorus ion (PI) is a new target for the design of tissue-engineered materials. Changing cellular response pattern to high PI can maintain monocyte/macrophage survival in TEBV and the signal of increasing PI can be converted by klotho to the adenosine signals through the regulation of energy metabolism in monocytes/macrophages.

  20. 75 FR 34320 - Asian Longhorned Beetle; Quarantined Area and Regulated Articles

    Science.gov (United States)

    2010-06-17

    ... Regulated Articles AGENCY: Animal and Plant Health Inspection Service, USDA. ACTION: Interim rule and... regulated articles from that area. We are also updating the list of regulated articles in order to reflect... regulated articles from quarantined areas to prevent the artificial spread of ALB to noninfested areas...

  1. Cyclophilin 20-3 relays a 12-oxo-phytodienoic acid signal during stress responsive regulation of cellular redox homeostasis.

    Science.gov (United States)

    Park, Sang-Wook; Li, Wei; Viehhauser, Andrea; He, Bin; Kim, Soonok; Nilsson, Anders K; Andersson, Mats X; Kittle, Joshua D; Ambavaram, Madana M R; Luan, Sheng; Esker, Alan R; Tholl, Dorothea; Cimini, Daniela; Ellerström, Mats; Coaker, Gitta; Mitchell, Thomas K; Pereira, Andy; Dietz, Karl-Josef; Lawrence, Christopher B

    2013-06-04

    The jasmonate family of phytohormones plays central roles in plant development and stress acclimation. However, the architecture of their signaling circuits remains largely unknown. Here we describe a jasmonate family binding protein, cyclophilin 20-3 (CYP20-3), which regulates stress-responsive cellular redox homeostasis. (+)-12-Oxo-phytodienoic acid (OPDA) binding promotes CYP20-3 to form a complex with serine acetyltransferase 1, which triggers the formation of a hetero-oligomeric cysteine synthase complex with O-acetylserine(thiol)lyase B in chloroplasts. The cysteine synthase complex formation then activates sulfur assimilation that leads to increased levels of thiol metabolites and the buildup of cellular reduction potential. The enhanced redox capacity in turn coordinates the expression of a subset of OPDA-responsive genes. Thus, we conclude that CYP20-3 is a key effector protein that links OPDA signaling to amino acid biosynthesis and cellular redox homeostasis in stress responses.

  2. Identification of genes that regulate multiple cellular processes/responses in the context of lipotoxicity to hepatoma cells

    Directory of Open Access Journals (Sweden)

    Yedwabnick Matthew

    2007-10-01

    Full Text Available Abstract Background In order to devise efficient treatments for complex, multi-factorial diseases, it is important to identify the genes which regulate multiple cellular processes. Exposure to elevated levels of free fatty acids (FFAs and tumor necrosis factor alpha (TNF-α alters multiple cellular processes, causing lipotoxicity. Intracellular lipid accumulation has been shown to reduce the lipotoxicity of saturated FFA. We hypothesized that the genes which simultaneously regulate lipid accumulation as well as cytotoxicity may provide better targets to counter lipotoxicity of saturated FFA. Results As a model system to test this hypothesis, human hepatoblastoma cells (HepG2 were exposed to elevated physiological levels of FFAs and TNF-α. Triglyceride (TG accumulation, toxicity and the genomic responses to the treatments were measured. Here, we present a framework to identify such genes in the context of lipotoxicity. The aim of the current study is to identify the genes that could be altered to treat or ameliorate the cellular responses affected by a complex disease rather than to identify the causal genes. Genes that regulate the TG accumulation, cytotoxicity or both were identified by a modified genetic algorithm partial least squares (GA/PLS analysis. The analyses identified NADH dehydrogenase and mitogen activated protein kinases (MAPKs as important regulators of both cytotoxicity and lipid accumulation in response to FFA and TNF-α exposure. In agreement with the predictions, inhibiting NADH dehydrogenase and c-Jun N-terminal kinase (JNK reduced cytotoxicity significantly and increased intracellular TG accumulation. Inhibiting another MAPK pathway, the extracellular signal regulated kinase (ERK, on the other hand, improved the cytotoxicity without changing TG accumulation. Much greater reduction in the toxicity was observed upon inhibiting the NADH dehydrogenase and MAPK (which were identified by the dual-response analysis, than for the

  3. Irradiation of cellular equipment and regulations for exposure to RF fields

    OpenAIRE

    Jairo Luís Beltrán Duque; Ángel Enrique Ochoa Urdaneta; María Fernanda Hernández Delgado

    2014-01-01

    ABSTRACTIn virtue of growing of cellular telephony use and the numerous discussions about repercussions in health, this investigation it is carried out with the objective of comparing the irradiation emitted by the cellular equipments of national circulation, with the established in the nationals and internationals norms to Radio Frequency Fields (RFF) exposition. Sustained in the irradiation theoryestablished (Hayt, 2006; Serway and Beichner, 2002), the Nationals and Internationals Norms to ...

  4. Irradiation of cellular equipment and regulations for exposure to RF fields

    OpenAIRE

    Jairo Luís Beltrán Duque; Ángel Enrique Ochoa Urdaneta; María Fernanda Hernández Delgado

    2014-01-01

    ABSTRACTIn virtue of growing of cellular telephony use and the numerous discussions about repercussions in health, this investigation it is carried out with the objective of comparing the irradiation emitted by the cellular equipments of national circulation, with the established in the nationals and internationals norms to Radio Frequency Fields (RFF) exposition. Sustained in the irradiation theoryestablished (Hayt, 2006; Serway and Beichner, 2002), the Nationals and Internationals Norms to ...

  5. Increasing the coverage area through relay node deployment in long term evolution advanced cellular networks

    Science.gov (United States)

    Aldhaibani, Jaafar A.; Ahmad, R. B.; Yahya, A.; Azeez, Suzan A.

    2015-05-01

    Wireless multi-hop relay networks have become very important technologies in mobile communications. These networks ensure high throughput and coverage extension with a low cost. The poor capacity at cell edges is not enough to meet with growing demand of high capacity and throughput irrespective of user's placement in the cellular network. In this paper we propose optimal placement of relay node that provides maximum achievable rate at users and enhances the throughput and coverage at cell edge region. The proposed scheme is based on the outage probability at users and taken on account the interference between nodes. Numerical analyses along with simulation results indicated there are an improvement in capacity for users at the cell edge is 40% increment from all cell capacity.

  6. Regulation of biofilm formation and cellular buoyancy through modulating intracellular cyclic di-GMP levels in engineered cyanobacteria.

    Science.gov (United States)

    Agostoni, Marco; Waters, Christopher M; Montgomery, Beronda L

    2016-02-01

    The second messenger cyclic dimeric (3'→5') GMP (cyclic di-GMP or c-di-GMP) has been implicated in the transition between motile and sessile lifestyles in bacteria. In this study, we demonstrate that biofilm formation, cellular aggregation or flocculation, and cellular buoyancy are under the control of c-di-GMP in Synechocystis sp. PCC 6803 (Synechocystis) and Fremyella diplosiphon. Synechocystis is a unicellular cyanobacterium and displays lower levels of c-di-GMP; F. diplosiphon is filamentous and displays higher intracellular c-di-GMP levels. We transformed Synechocystis and F. diplosiphon with a plasmid for constitutive expression of genes encoding diguanylate cylase (DGC) and phosphodiesterase (PDE) proteins from Vibrio cholerae or Escherichia coli, respectively. These engineered strains allowed us to modulate intracellular c-di-GMP levels. Biofilm formation and cellular deposition were induced in the DGC-expressing Synechocystis strain which exhibited high intracellular levels of c-di-GMP; whereas strains expressing PDE in Synechocystis and F. diplosiphon to drive low intracellular levels of c-di-GMP exhibited enhanced cellular buoyancy. In addition, the PDE-expressing F. diplosiphon strain showed elevated chlorophyll levels. These results imply roles for coordinating c-di-GMP homeostasis in regulating native cyanobacterial phenotypes. Engineering exogenous DGC or PDE proteins to regulate intracellular c-di-GMP levels represents an effective tool for uncovering cryptic phenotypes or modulating phenotypes in cyanobacteria for practical applications in biotechnology applicable in photobioreactors and in green biotechnologies, such as energy-efficient harvesting of cellular biomass or the treatment of metal-containing wastewaters.

  7. Negative Regulation of IRF7 Activation by ATF4 Suggests a Cross Regulation Between the Interferon Responses and the Cellular Integrated Stress Responses

    OpenAIRE

    Liang, Qiming; Deng, Hongying; Sun, Chiao-Wang; Tim M. Townes; Zhu, Fanxiu

    2010-01-01

    Cells react to viral infection by exhibiting interferon (IFN)-based innate immune responses and integrated stress responses, but little is known about the interrelationships between the two. We here report a linkage between these two host protective cellular mechanisms. We found that IRF7, the master regulator of type I IFN gene expression, interacts with ATF4, a key component of the integrated stress responses whose translation is induced by viral infection and various stresses. We have demo...

  8. Reverse Transcriptase and Cellular Factors: Regulators of HIV-1 Reverse Transcription

    Directory of Open Access Journals (Sweden)

    David Harrich

    2009-11-01

    Full Text Available There is ample evidence that synthesis of HIV-1 proviral DNA from the viral RNA genome during reverse transcription requires host factors. However, only a few cellular proteins have been described in detail that affect reverse transcription and interact with reverse transcriptase (RT. HIV-1 integrase is an RT binding protein and a number of IN-binding proteins including INI1, components of the Sin3a complex, and Gemin2 affect reverse transcription. In addition, recent studies implicate the cellular proteins HuR, AKAP149, and DNA topoisomerase I in reverse transcription through an interaction with RT. In this review we will consider interactions of reverse transcription complex with viral and cellular factors and how they affect the reverse transcription process.

  9. Epigenetic regulation of cellular memory by the Polycomb and Trithorax group proteins.

    Science.gov (United States)

    Ringrose, Leonie; Paro, Renato

    2004-01-01

    During the development of multicellular organisms, cells become different from one another by changing their genetic program in response to transient stimuli. Long after the stimulus is gone, "cellular memory" mechanisms enable cells to remember their chosen fate over many cell divisions. The Polycomb and Trithorax groups of proteins, respectively, work to maintain repressed or active transcription states of developmentally important genes through many rounds of cell division. Here we review current ideas on the protein and DNA components of this transcriptional memory system and how they interact dynamically with each other to orchestrate cellular memory for several hundred genes.

  10. Involvement of the interferon-regulated antiviral proteins PKR and RNase L in reovirus-induced shutoff of cellular translation.

    Science.gov (United States)

    Smith, Jennifer A; Schmechel, Stephen C; Williams, Bryan R G; Silverman, Robert H; Schiff, Leslie A

    2005-02-01

    Cellular translation is inhibited following infection with most strains of reovirus, but the mechanisms responsible for this phenomenon remain to be elucidated. The extent of host shutoff varies in a strain-dependent manner; infection with the majority of strains leads to strong host shutoff, while infection with strain Dearing results in minimal inhibition of cellular translation. A genetic study with reassortant viruses and subsequent biochemical analyses led to the hypothesis that the interferon-induced, double-stranded RNA-activated protein kinase, PKR, is responsible for reovirus-induced host shutoff. To directly determine whether PKR is responsible for reovirus-induced host shutoff, we used a panel of reovirus strains and mouse embryo fibroblasts derived from knockout mice. This approach revealed that PKR contributes to but is not wholly responsible for reovirus-induced host shutoff. Studies with cells lacking RNase L, the endoribonuclease component of the interferon-regulated 2',5'-oligoadenylate synthetase-RNase L system, demonstrated that RNase L also down-regulates cellular protein synthesis in reovirus-infected cells. In many viral systems, PKR and RNase L have well-characterized antiviral functions. An analysis of reovirus replication in cells lacking these molecules indicated that, while they contributed to host shutoff, neither PKR nor RNase L exerted an antiviral effect on reovirus growth. In fact, some strains of reovirus replicated more efficiently in the presence of PKR and RNase L than in their absence. Data presented in this report illustrate that the inhibition of cellular translation following reovirus infection is complex and involves multiple interferon-regulated gene products. In addition, our results suggest that reovirus has evolved effective mechanisms to avoid the actions of the interferon-stimulated antiviral pathways that include PKR and RNase L and may even benefit from their expression.

  11. Substrate Stiffness and Cell Area Predict Cellular Traction Stresses in Single Cells and Cells in Contact

    OpenAIRE

    Califano, Joseph P.; Reinhart-King, Cynthia A.

    2010-01-01

    Cells generate traction stresses against their substrate during adhesion and migration, and traction stresses are used in part by the cell to sense the substrate. While it is clear that traction stresses, substrate stiffness, and cell area are related, it is unclear whether or how area and substrate stiffness affect force generation in cells. Moreover, multiple studies have investigated traction stresses of single cells, but few have focused on forces exerted by cells in contact, which more c...

  12. On the area spectral efficiency improvement of heterogeneous network by exploiting the integration of macro-femto cellular networks

    KAUST Repository

    Shakir, Muhammad

    2012-06-01

    Heterogeneous networks are an attractive means of expanding mobile network capacity. A heterogeneous network is typically composed of multiple radio access technologies (RATs) where the base stations are transmitting with variable power. In this paper, we consider a Heterogeneous network where we complement the macrocell network with low-power low-cost user deployed nodes, such as femtocell base stations to increase the mean achievable capacity of the system. In this context, we integrate macro-femto cellular networks and derive the area spectral efficiency of the proposed two tier Heterogeneous network. We consider the deployment of femtocell base stations around the edge of the macrocell such that this configuration is referred to as femto-on-edge (FOE) configuration. Moreover, FOE configuration mandates reduction in intercell interference due to the mobile users which are located around the edge of the macrocell since these femtocell base stations are low-power nodes which has significantly lower transmission power than macrocell base stations. We present a mathematical analysis to calculate the instantaneous carrier to interference ratio (CIR) of the desired mobile user in macro and femto cellular networks and determine the total area spectral efficiency of the Heterogeneous network. Details of the simulation processes are included to support the analysis and show the efficacy of the proposed deployment. It has been shown that the proposed setup of the Heterogeneous network offers higher area spectral efficiency which aims to fulfill the expected demand of the future mobile users. © 2012 IEEE.

  13. Bone remodeling in the context of cellular and systemic regulation: the role of osteocytes and the nervous system.

    Science.gov (United States)

    Niedźwiedzki, Tadeusz; Filipowska, Joanna

    2015-10-01

    Bone is a dynamic tissue that undergoes constant remodeling. The appropriate course of this process determines development and regeneration of the skeleton. Tight molecular control of bone remodeling is vital for the maintenance of appropriate physiology and microarchitecture of the bone, providing homeostasis, also at the systemic level. The process of remodeling is regulated by a rich innervation of the skeleton, being the source of various growth factors, neurotransmitters, and hormones regulating function of the bone. Although the course of bone remodeling at the cellular level is mainly associated with the activity of osteoclasts and osteoblasts, recently also osteocytes have gained a growing interest as the principal regulators of bone turnover. Osteocytes play a significant role in the regulation of osteogenesis, releasing sclerostin (SOST), an inhibitor of bone formation. The process of bone turnover, especially osteogenesis, is also modulated by extra-skeletal molecules. Proliferation and differentiation of osteoblasts are promoted by the brain-derived serotonin and hypothetically inhibited by its intestinal equivalent. The activity of SOST and serotonin is either directly or indirectly associated with the canonical Wnt/β-catenin signaling pathway, the main regulatory pathway of osteoblasts function. The impairment of bone remodeling may lead to many skeletal diseases, such as high bone mass syndrome or osteoporosis. In this paper, we review the most recent data on the cellular and molecular mechanisms of bone remodeling control, with particular emphasis on the role of osteocytes and the nervous system in this process.

  14. Protease activated receptor-1 regulates macrophage-mediated cellular senescence : a risk for idiopathic pulmonary fibrosis

    NARCIS (Netherlands)

    Lin, Cong; Rezaee, Farhad; Waasdorp, Maaike; Shi, Kun; van der Poll, Tom; Borensztajn, Keren; Spek, C. Arnold

    2015-01-01

    Idiopathic pulmonary fibrosis (IPF) is a destructive disease in part resulting from premature or mature cellular aging. Protease-activated receptor-1 (PAR-1) recently emerged as a critical component in the context of fibrotic lung diseases. Therefore, we aimed to study the role of macrophages in PAR

  15. Herpes simplex virus 1 VP22 regulates translocation of multiple viral and cellular proteins and promotes neurovirulence.

    Science.gov (United States)

    Tanaka, Michiko; Kato, Akihisa; Satoh, Yuko; Ide, Takahiro; Sagou, Ken; Kimura, Kayo; Hasegawa, Hideki; Kawaguchi, Yasushi

    2012-05-01

    Herpes simplex virus 1 (HSV-1) protein VP22, encoded by the UL49 gene, is a major virion tegument protein. In the present study, we showed that VP22 was required for efficient redistribution of viral proteins VP16, VP26, ICP0, ICP4, and ICP27 and of cellular protein Hsc-70 to the cytoplasm of infected cells. We found that two dileucine motifs in VP22, at amino acids 235 and 236 and amino acids 251 and 252, were necessary for VP22 regulation of the proper cytoplasmic localization of these viral and cellular proteins. The dileucine motifs were also required for proper cytoplasmic localization of VP22 itself and for optimal expression of viral proteins VP16, VP22, ICP0, UL41, and glycoprotein B. Interestingly, a recombinant mutant virus with alanines substituted for the dileucines at amino acids 251 and 252 had a 50% lethal dose (LD(50)) for neurovirulence in mice following intracerebral inoculation about 10(3)-fold lower than the LD(50) of the repaired virus. Furthermore, the replication and spread of this mutant virus in the brains of mice following intracerebral inoculation were significantly impaired relative to those of the repaired virus. The ability of VP22 to regulate the localization and expression of various viral and cellular proteins, as shown in this study, was correlated with an increase in viral replication and neurovirulence in the experimental murine model. Thus, HSV-1 VP22 is a significant neurovirulence factor in vivo.

  16. A chemical biology approach to interrogate quorum-sensing regulated behaviors at the molecular and cellular level.

    Science.gov (United States)

    Lowery, Colin A; Matamouros, Susana; Niessen, Sherry; Zhu, Jie; Scolnick, Jonathan; Lively, Jenny M; Cravatt, Benjamin F; Miller, Samuel I; Kaufmann, Gunnar F; Janda, Kim D

    2013-07-25

    Small molecule probes have been used extensively to explore biologic systems and elucidate cellular signaling pathways. In this study, we use an inhibitor of bacterial communication to monitor changes in the proteome of Salmonella enterica serovar Typhimurium with the aim of discovering unrecognized processes regulated by AI-2-based quorum-sensing (QS), a mechanism of bacterial intercellular communication that allows for the coordination of gene expression in a cell density-dependent manner. In S. typhimurium, this system regulates the uptake and catabolism of intercellular signals and has been implicated in pathogenesis, including the invasion of host epithelial cells. We demonstrate that our QS antagonist is capable of selectively inhibiting the expression of known QS-regulated proteins in S. typhimurium, thus attesting that QS inhibitors may be used to confirm proposed and elucidate previously unidentified QS pathways without relying on genetic manipulation.

  17. Some aspects of the implementation of the Regulation on Reclaiming Mining Areas of 4th November 1985 - Reclaiming Regulation. [GDR

    Energy Technology Data Exchange (ETDEWEB)

    Hagen, C.; Hildmann, E.; Waltemate, G.

    1986-03-01

    The Regulation on Reclaiming Mining Areas concerns the revegetation of areas used for prospecting, mining and storage. Quality parameters are stated which are to ensure productive use by the next users.

  18. Cellular energy stress induces AMPK-mediated regulation of YAP and the Hippo pathway.

    Science.gov (United States)

    Mo, Jung-Soon; Meng, Zhipeng; Kim, Young Chul; Park, Hyun Woo; Hansen, Carsten Gram; Kim, Soohyun; Lim, Dae-Sik; Guan, Kun-Liang

    2015-04-01

    YAP (Yes-associated protein) is a transcription co-activator in the Hippo tumour suppressor pathway and controls cell growth, tissue homeostasis and organ size. YAP is inhibited by the kinase Lats, which phosphorylates YAP to induce its cytoplasmic localization and proteasomal degradation. YAP induces gene expression by binding to the TEAD family transcription factors. Dysregulation of the Hippo-YAP pathway is frequently observed in human cancers. Here we show that cellular energy stress induces YAP phosphorylation, in part due to AMPK-dependent Lats activation, thereby inhibiting YAP activity. Moreover, AMPK directly phosphorylates YAP Ser 94, a residue essential for the interaction with TEAD, thus disrupting the YAP-TEAD interaction. AMPK-induced YAP inhibition can suppress oncogenic transformation of Lats-null cells with high YAP activity. Our study establishes a molecular mechanism and functional significance of AMPK in linking cellular energy status to the Hippo-YAP pathway.

  19. Static allometry of unicellular green algae: scaling of cellular surface area and volume in the genus Micrasterias (Desmidiales).

    Science.gov (United States)

    Neustupa, J

    2016-02-01

    The surface area-to-volume ratio of cells is one of the key factors affecting fundamental biological processes and, thus, fitness of unicellular organisms. One of the general models for allometric increase in surface-to-volume scaling involves fractal-like elaboration of cellular surfaces. However, specific data illustrating this pattern in natural populations of the unicellular organisms have not previously been available. This study shows that unicellular green algae of the genus Micrasterias (Desmidiales) have positive allometric surface-to-volume scaling caused by changes in morphology of individual species, especially in the degree of cell lobulation. This allometric pattern was also detected within most of the cultured and natural populations analysed. Values of the allometric S:V scaling within individual populations were closely correlated to the phylogenetic structure of the clade. In addition, they were related to species-specific cellular morphology. Individual populations differed in their allometric patterns, and their position in the allometric space was strongly correlated with the degree of allometric S:V scaling. This result illustrates that allometric shape patterns are an important correlate of the capacity of individual populations to compensate for increases in their cell volumes by increasing the surface area. However, variation in allometric patterns was not associated with phylogenetic structure. This indicates that the position of the populations in the allometric space was not evolutionarily conserved and might be influenced by environmental factors.

  20. ECM signaling regulates collective cellular dynamics to control pancreas branching morphogenesis

    OpenAIRE

    2015-01-01

    During pancreas development, epithelial buds undergo branching morphogenesis to form an exocrine and endocrine gland. Proper morphogenesis is necessary for correct lineage allocation of pancreatic progenitors; however, the cellular events underlying pancreas morphogenesis are unknown. Here, we employed time-lapse microscopy and fluorescent labeling of cells to analyze cell behaviors associated with pancreas morphogenesis. We observed that outer bud cells adjacent to the basement membrane are ...

  1. Mechanisms and Regulation of Intestinal Absorption of Water-soluble Vitamins: Cellular and Molecular Aspects

    DEFF Research Database (Denmark)

    Nexø, Ebba; Said, Hamid M

    2012-01-01

    The water-soluble vitamins represent a group of structurally and functionally unrelated compounds that share the common feature of being essential for normal cellular functions, growth, and development. With the exception of some endogenous production of niacin, human cells cannot synthesize...... or deficiency. An impaired absorptive function occurs in a variety of conditions including congenital defects in the digestive or absorptive processes, intestinal diseases, drug interaction, and chronic alcohol use....

  2. Reactive oxygen species (ROS) homeostasis and redox regulation in cellular signaling

    OpenAIRE

    2012-01-01

    Reactive oxygen species (ROS) are generated during mitochondrial oxidative metabolism as well as in cellular response to xenobiotics, cytokines, and bacterial invasion. Oxidative stress refers to the imbalance due to excess ROS or oxidants over the capability of the cell to mount an effective antioxidant response. Oxidative stress results in macromolecular damage and is implicated in various disease states such as atherosclerosis, diabetes, cancer, neurodegeneration, and aging. Paradoxically,...

  3. IGF-II and IGFBP-6 regulate cellular contractility and proliferation in Dupuytren's disease.

    Science.gov (United States)

    Raykha, Christina; Crawford, Justin; Gan, Bing Siang; Fu, Ping; Bach, Leon A; O'Gorman, David B

    2013-10-01

    Dupuytren's disease (DD) is a common and heritable fibrosis of the palmar fascia that typically manifests as permanent finger contractures. The molecular interactions that induce the development of hyper-contractile fibroblasts, or myofibroblasts, in DD are poorly understood. We have identified IGF2 and IGFBP6, encoding insulin-like growth factor (IGF)-II and IGF binding protein (IGFBP)-6 respectively, as reciprocally dysregulated genes and proteins in primary cells derived from contracture tissues (DD cells). Recombinant IGFBP-6 inhibited the proliferation of DD cells, patient-matched control (PF) cells and normal palmar fascia (CT) cells. Co-treatments with IGF-II, a high affinity IGFBP-6 ligand, were unable to rescue these effects. A non-IGF-II binding analog of IGFBP-6 also inhibited cellular proliferation, implicating IGF-II-independent roles for IGFBP-6 in this process. IGF-II enhanced the proliferation of CT cells, but not DD or PF cells, and significantly enhanced DD and PF cell contractility in stressed collagen lattices. While IGFBP-6 treatment did not affect cellular contractility, it abrogated the IGF-II-induced contractility of DD and PF cells in stressed collagen lattices. IGF-II also significantly increased the contraction of DD cells in relaxed lattices, however this effect was not evident in relaxed collagen lattices containing PF cells. The disparate effects of IGF-II on DD and PF cells in relaxed and stressed contraction models suggest that IGF-II can enhance lattice contractility through more than one mechanism. This is the first report to implicate IGFBP-6 as a suppressor of cellular proliferation and IGF-II as an inducer of cellular contractility in this connective tissue disease.

  4. Cellular Mechanisms in Regulating Mammary Cell Turnover During Lactation and Dry Period in Dairy Cows

    DEFF Research Database (Denmark)

    Nørgaard, J V; Theil, P K; Sørensen, M T

    2008-01-01

    The mechanisms involved in regulating mammary cell turnover during the pregnancy-lactaion cycle in dairy cows are unclear. The objective of present experiment was to describe expression of genes encoding proteins known to be involved in pathways regulating mammary cell proliferation, apoptosis......, differentiation, cell survival, and tissue remodeling....

  5. 33 CFR 165.1301 - Puget Sound and Adjacent Waters in Northwestern Washington-Regulated Navigation Area.

    Science.gov (United States)

    2010-07-01

    ... in Northwestern Washington-Regulated Navigation Area. 165.1301 Section 165.1301 Navigation and... REGULATED NAVIGATION AREAS AND LIMITED ACCESS AREAS Specific Regulated Navigation Areas and Limited Access... Washington—Regulated Navigation Area. The following is a regulated navigation area—All of the following...

  6. Cytosolic iron-sulfur cluster assembly (CIA) system: factors, mechanism, and relevance to cellular iron regulation.

    Science.gov (United States)

    Sharma, Anil K; Pallesen, Leif J; Spang, Robert J; Walden, William E

    2010-08-27

    FeS cluster biogenesis is an essential process in virtually all forms of life. Complex protein machineries that are conserved from bacteria through higher eukaryotes facilitate assembly of the FeS cofactor in proteins. In the last several years, significant strides have been made in our understanding of FeS cluster assembly and the functional overlap of this process with cellular iron homeostasis. This minireview summarizes the present understanding of the cytosolic iron-sulfur cluster assembly (CIA) system in eukaryotes, with a focus on information gained from studies in budding yeast and mammalian systems.

  7. Cellular resolution models for even skipped regulation in the entire Drosophila embryo

    OpenAIRE

    Ilsley, Garth R; Fisher, Jasmin; Apweiler, Rolf; Angela H. DePace; Nicholas M Luscombe

    2013-01-01

    eLife digest The transcription of genes into messenger RNA (mRNA) molecules is one of the most important processes in biology, but our present understanding of this process is largely qualitative. Molecules such as transcription factors and regions of DNA other than the region that codes for the mRNA are known to interact with each other to influence the onset of transcription, and also the rate at which it occurs. However, given the cellular concentrations of transcription factors in a devel...

  8. 33 CFR 165.122 - Regulated Navigation Area: Navigable waters within Narragansett Bay and the Providence River...

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Regulated Navigation Area... SAFETY REGULATED NAVIGATION AREAS AND LIMITED ACCESS AREAS Specific Regulated Navigation Areas and Limited Access Areas First Coast Guard District § 165.122 Regulated Navigation Area: Navigable waters...

  9. Control of intestinal promoter activity of the cellular migratory regulator gene ELMO3 by CDX2 and SP1

    DEFF Research Database (Denmark)

    Coskun, Mehmet; Boyd, Mette; Olsen, Jørgen;

    2010-01-01

    An important aspect of the cellular differentiation in the intestine is the migration of epithelial cells from the crypt to the villus tip. As homeodomaine transcription factor CDX2 has been suggested to influence cell migration, we performed a genome-wide promoter analysis for CDX2 binding...... migration. However, no information is available about the transcriptional regulation of the ELMO3 gene. The aim of this study was to investigate the potential role of CDX2 in the regulation of the ELMO3 promoter activity. Electrophoretic mobility shift assays showed that CDX2 bound to conserved CDX2...... sequences and mutations of the CDX2-binding sites, significantly reduced the promoter activity. Reporter gene assays demonstrated that the region mediating ELMO3 basal transcriptional activity to be located between -270 and -31 bp. Sequence analysis revealed no typical TATA-box, but four GC-rich sequences...

  10. Biochemical and cellular mechanisms regulating Acanthamoeba castellanii adherence to host cells.

    Science.gov (United States)

    Soto-Arredondo, K J; Flores-Villavicencio, L L; Serrano-Luna, J J; Shibayama, M; Sabanero-López, M

    2014-04-01

    Free-living amoebae belonging to the genus Acanthamoeba are the causative agents of infections such as amoebic keratitis (AK), granulomatous amoebic encephalitis (GAE) and cutaneous lesions. The mechanisms involved in the establishment of infection are unknown. However, it is accepted that the initial phase of pathogenesis involves adherence to the host tissue. In this work, we analysed surface molecules with an affinity for epithelial and neuronal cells from the trophozoites of Acanthamoeba castellanii. We also investigated the cellular mechanisms that govern the process of trophozoite adhesion to the host cells. We first used confocal and epifluorescence microscopy to examine the distribution of the A. castellanii actin cytoskeleton during interaction with the host cells. The use of drugs, as cytochalasin B (CB) and latrunculin B (LB), revealed the participation of cytoskeletal filaments in the adhesion process. In addition, to identify the proteins and glycoproteins on the surface of A. castellanii, the trophozoites were labelled with biotin and biotinylated lectins. The results revealed bands of surface proteins, some of which were glycoproteins with mannose and N-acetylglucosamine residues. Interaction assays of biotinylated amoebae proteins with epithelial and neuronal cells showed that some surface proteins had affinity for both cell types. The results of this study provide insight into the biochemical and cellular mechanisms of the Acanthamoeba infection process.

  11. A biphasic endothelial stress-survival mechanism regulates the cellular response to vascular endothelial growth factor A

    Energy Technology Data Exchange (ETDEWEB)

    Latham, Antony M.; Odell, Adam F. [Endothelial Cell Biology Unit, School of Molecular and Cellular Biology, University of Leeds, Leeds LS2 9JT (United Kingdom); Mughal, Nadeem A. [Leeds Vascular Institute, Leeds General Infirmary, Great George Street, Leeds LS1 3EX (United Kingdom); Issitt, Theo; Ulyatt, Clare; Walker, John H. [Endothelial Cell Biology Unit, School of Molecular and Cellular Biology, University of Leeds, Leeds LS2 9JT (United Kingdom); Homer-Vanniasinkam, Shervanthi [Leeds Vascular Institute, Leeds General Infirmary, Great George Street, Leeds LS1 3EX (United Kingdom); Ponnambalam, Sreenivasan, E-mail: s.ponnambalam@leeds.ac.uk [Endothelial Cell Biology Unit, School of Molecular and Cellular Biology, University of Leeds, Leeds LS2 9JT (United Kingdom)

    2012-11-01

    Vascular endothelial growth factor A (VEGF-A) is an essential cytokine that regulates endothelial function and angiogenesis. VEGF-A binding to endothelial receptor tyrosine kinases such as VEGFR1 and VEGFR2 triggers cellular responses including survival, proliferation and new blood vessel sprouting. Increased levels of a soluble VEGFR1 splice variant (sFlt-1) correlate with endothelial dysfunction in pathologies such as pre-eclampsia; however the cellular mechanism(s) underlying the regulation and function of sFlt-1 are unclear. Here, we demonstrate the existence of a biphasic stress response in endothelial cells, using serum deprivation as a model of endothelial dysfunction. The early phase is characterized by a high VEGFR2:sFlt-1 ratio, which is reversed in the late phase. A functional consequence is a short-term increase in VEGF-A-stimulated intracellular signaling. In the late phase, sFlt-1 is secreted and deposited at the extracellular matrix. We hypothesized that under stress, increased endothelial sFlt-1 levels reduce VEGF-A bioavailability: VEGF-A treatment induces sFlt-1 expression at the cell surface and VEGF-A silencing inhibits sFlt-1 anchorage to the extracellular matrix. Treatment with recombinant sFlt-1 inhibits VEGF-A-stimulated in vitro angiogenesis and sFlt-1 silencing enhances this process. In this response, increased VEGFR2 levels are regulated by the phosphatidylinositol-3-kinase and PKB/Akt signaling pathways and increased sFlt-1 levels by the ERK1/2 signaling pathway. We conclude that during serum withdrawal, cellular sensing of environmental stress modulates sFlt-1 and VEGFR2 levels, regulating VEGF-A bioavailability and ensuring cell survival takes precedence over cell proliferation and migration. These findings may underpin an important mechanism contributing to endothelial dysfunction in pathological states. -- Highlights: Black-Right-Pointing-Pointer Endothelial cells mount a stress response under conditions of low serum. Black

  12. 32 CFR 552.25 - Entry regulations for certain Army training areas in Hawaii.

    Science.gov (United States)

    2010-07-01

    ... in Hawaii. 552.25 Section 552.25 National Defense Department of Defense (Continued) DEPARTMENT OF THE... Regulations for Certain Army Training Areas in Hawaii § 552.25 Entry regulations for certain Army training areas in Hawaii. (a) Purpose. (1) This regulation establishes procedures governing the entry onto...

  13. SaeRS Is Responsive to Cellular Respiratory Status and Regulates Fermentative Biofilm Formation in Staphylococcus aureus.

    Science.gov (United States)

    Mashruwala, Ameya A; Gries, Casey M; Scherr, Tyler D; Kielian, Tammy; Boyd, Jeffrey M

    2017-08-01

    Biofilms are multicellular communities of microorganisms living as a quorum rather than as individual cells. The bacterial human pathogen Staphylococcus aureus uses oxygen as a terminal electron acceptor during respiration. Infected human tissues are hypoxic or anoxic. We recently reported that impaired respiration elicits a programmed cell lysis (PCL) phenomenon in S. aureus leading to the release of cellular polymers that are utilized to form biofilms. PCL is dependent upon the AtlA murein hydrolase and is regulated, in part, by the SrrAB two-component regulatory system (TCRS). In the current study, we report that the SaeRS TCRS also governs fermentative biofilm formation by positively influencing AtlA activity. The SaeRS-modulated factor fibronectin-binding protein A (FnBPA) also contributed to the fermentative biofilm formation phenotype. SaeRS-dependent biofilm formation occurred in response to changes in cellular respiratory status. Genetic evidence presented suggests that a high cellular titer of phosphorylated SaeR is required for biofilm formation. Epistasis analyses found that SaeRS and SrrAB influence biofilm formation independently of one another. Analyses using a mouse model of orthopedic implant-associated biofilm formation found that both SaeRS and SrrAB govern host colonization. Of these two TCRSs, SrrAB was the dominant system driving biofilm formation in vivo We propose a model wherein impaired cellular respiration stimulates SaeRS via an as yet undefined signal molecule(s), resulting in increasing expression of AtlA and FnBPA and biofilm formation. Copyright © 2017 American Society for Microbiology.

  14. The cellular protooncogenes c-fos and egr-1 are regulated by prostacyclin in rodent osteoblasts and fibroblasts.

    Science.gov (United States)

    Glantschnig, H; Varga, F; Klaushofer, K

    1996-11-01

    PGs are local regulators of various cellular functions. They exert their effects via specific PG receptor subtypes. Induction of c-fos gene expression has been described for arachidonic acid and its metabolite PGE2. We demonstrate that another very short half-lifed prostanoid metabolite, namely prostacyclin (PGI2), is a regulator of immediate-early genes. PGI2 transiently induced the growth-associated immediate-early genes c-fos and egr-1 in osteoblastic as well as fibroblastic cell lines. Furthermore, we showed that PGI2 dose dependently stimulated new DNA synthesis in the osteoblastic cell line MC3T3-E1. Although PGI2 is known to be a potent inducer of cyclooxygenases, we showed that this pathway is not necessary for protooncogene induction by PGI2. Our data indicate a direct effect of PGI2 on immediate-early gene expression, which does not depend on the synthesis of other prostanoids. Intracellular signal transduction mechanisms were studied with the protein kinase inhibitor H-7, a potent inhibitor of PGI2-induced c-fos expression. Experiments with phorbol esters revealed that protein kinase C activity is not obligatory for the effect of PGI2 on c-fos expression. We conclude from these results that PGI2, a rapidly inactivated prostanoid, has a major impact on cellular oncogene expression and growth in mesenchymally derived cells.

  15. The Rho GTPase Cdc42 regulates hair cell planar polarity and cellular patterning in the developing cochlea.

    Science.gov (United States)

    Kirjavainen, Anna; Laos, Maarja; Anttonen, Tommi; Pirvola, Ulla

    2015-03-13

    Hair cells of the organ of Corti (OC) of the cochlea exhibit distinct planar polarity, both at the tissue and cellular level. Planar polarity at tissue level is manifested as uniform orientation of the hair cell stereociliary bundles. Hair cell intrinsic polarity is defined as structural hair bundle asymmetry; positioning of the kinocilium/basal body complex at the vertex of the V-shaped bundle. Consistent with strong apical polarity, the hair cell apex displays prominent actin and microtubule cytoskeletons. The Rho GTPase Cdc42 regulates cytoskeletal dynamics and polarization of various cell types, and, thus, serves as a candidate regulator of hair cell polarity. We have here induced Cdc42 inactivation in the late-embryonic OC. We show the role of Cdc42 in the establishment of planar polarity of hair cells and in cellular patterning. Abnormal planar polarity was displayed as disturbances in hair bundle orientation and morphology and in kinocilium/basal body positioning. These defects were accompanied by a disorganized cell-surface microtubule network. Atypical protein kinase C (aPKC), a putative Cdc42 effector, colocalized with Cdc42 at the hair cell apex, and aPKC expression was altered upon Cdc42 depletion. Our data suggest that Cdc42 together with aPKC is part of the machinery establishing hair cell planar polarity and that Cdc42 acts on polarity through the cell-surface microtubule network. The data also suggest that defects in apical polarization are influenced by disturbed cellular patterning in the OC. In addition, our data demonstrates that Cdc42 is required for stereociliogenesis in the immature cochlea.

  16. Interleukin-27 inhibits vaccine-enhanced pulmonary disease following respiratory syncytial virus infection by regulating cellular memory responses.

    Science.gov (United States)

    Zeng, Ruihong; Zhang, Huixian; Hai, Yan; Cui, Yuxiu; Wei, Lin; Li, Na; Liu, Jianxun; Li, Caixia; Liu, Ying

    2012-04-01

    Respiratory syncytial virus (RSV) is the most important cause of lower respiratory tract disease in young children. In the 1960s, infants vaccinated with formalin-inactivated RSV developed a more severe disease characterized by excessive inflammatory immunopathology in lungs upon natural RSV infection. The fear of causing the vaccine-enhanced disease (VED) is an important obstacle for development of safe and effective RSV vaccines. The recombinant vaccine candidate G1F/M2 immunization also led to VED. It has been proved that cellular memory induced by RSV vaccines contributed to VED. Interleukin-27 (IL-27) and IL-23 regulate Th1, Th17, and/or Th2 cellular immune responses. In this study, mice coimmunized with pcDNA3-IL-27 and G1F/M2 were fully protected and, importantly, did not develop vaccine-enhanced inflammatory responses and immunopathology in lungs after RSV challenge, which was correlated with moderate Th1-, suppressed Th2-, and Th17-like memory responses activated by RSV. In contrast, G1F/M2- or pcDNA3-IL-23+G1F/M2-immunized mice, in which robust Th2- and Th17-like memory responses were induced, developed enhanced pulmonary inflammation and severe immunopathology. Mice coimmunized with G1F/M2 and the two cytokine plasmids exhibited mild inflammatory responses as well as remarkable Th1-, suppressed Th2-, and Th17-like memory responses. These results suggested that Th1-, Th2-, and Th17-like memory responses and, in particular, excessive Th2- and Th17-like memory responses were closely associated with VED; IL-27 may inhibit VED following respiratory syncytial virus infection by regulating cellular memory responses.

  17. Thioredoxin-dependent Redox Regulation of Cellular Signaling and Stress Response through Reversible Oxidation of Methionines

    Energy Technology Data Exchange (ETDEWEB)

    Bigelow, Diana J.; Squier, Thomas C.

    2011-06-01

    Generation of reactive oxygen species (ROS) is a common feature of many forms of stress to which plants are exposed. Successful adaptation to changing environmental conditions requires sensitive sensors of ROS such as protein-bound methionines that are converted to their corresponding methionine sulfoxides, which in turn can influence cellular signaling pathways. Such a signaling protein is calmodulin, which represents an early and central point in calcium signaling pathways important to stress response in plants. We describe recent work elucidating fundamental mechanisms of reversible methionine oxidation within calmodulin, including the sensitivity of individual methionines within plant and animal calmodulin to ROS, the structural and functional consequences of their oxidation, and the interactions of oxidized calmodulin with methionine sulfoxide reductase enzymes.

  18. A Novel Chitosan CpG Nanoparticle Regulates Cellular and Humoral Immunity of Mice

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    To develop a safe and novel immunoadjuvant to enhance the immunity and resistance of animals against E.coli infection. Methods An 88-base immunostimulatory oligodeoxynuleotide containing eleven CpG motifs (CpG ODN)was synthesized and amplified by PCR. The chitosan nanoparticle (CNP) was prepared by ion linking method to entrap the CpG ODN that significantly promotes the proliferation of lymphocytes of pig in vitro. Then the CpG- CNP was inoculated into 21-day old Kunming mice, which were orally challenged with virulent K88/K99 E. Coli 35 days after inoculation. Blood was collected from the tail vein of mice on days 0, 7, 14, 21, 28, 35, 42, and 49 after inoculation to detect the changes and content of immunoglobulins, cytokines and immune cells by ELISA, such as IgG, IgA, IgM, IL-2, IL-4, and IL-6. Results The CpG provoked remarkable proliferation of lymphocytes of pig in vitro in comparison with that of control group (P<0.05). The inoculation with CpG-CNP significantly raised the content of IgG, IgM, and IgA in the sera of immunized mice (P<0.05). The levels of IL-2, IL-4, and IL-6 in the mice significantly increased in comparison with those in controls (P<0.05), so was the number of white blood cells and lymphocytes in immunized mice. The humoral and cellular immunities were significantly enhanced in immunized mice, which resisted the infection of E. coli and survived, while the control mice manifested evident symptoms and lesions of infection. Conclusions CpG-CNP can significantly promote cellular and humoral immunity and resistance of mice against E. coli infection, and can be utilized as an effective adjuvant to improve the immunoprotection and resistance of porcine against infectious disease.

  19. Selenoprotein H suppresses cellular senescence through genome maintenance and redox regulation.

    Science.gov (United States)

    Wu, Ryan T Y; Cao, Lei; Chen, Benjamin P C; Cheng, Wen-Hsing

    2014-12-05

    Oxidative stress and persistent DNA damage response contribute to cellular senescence, a degeneration process critically involving ataxia telangiectasia-mutated (ATM) and p53. Selenoprotein H (SelH), a nuclear selenoprotein, is proposed to carry redox and transactivation domains. To determine the role of SelH in genome maintenance, shRNA knockdown was employed in human normal and immortalized cell lines. SelH shRNA MRC-5 diploid fibroblasts under ambient O2 displayed a distinct profile of senescence including β-galactosidase expression, autofluorescence, growth inhibition, and ATM pathway activation. Such senescence phenotypes were alleviated in the presence of ATM kinase inhibitors, by p53 shRNA knockdown, or by maintaining the cells under 3% O2. During the course of 5-day recovery, the induction of phospho-ATM on Ser-1981 and γH2AX by H2O2 treatment (20 μm) subsided in scrambled shRNA but exacerbated in SelH shRNA MRC-5 cells. Results from clonogenic assays demonstrated hypersensitivity of SelH shRNA HeLa cells to paraquat and H2O2, but not to hydroxyurea, neocarzinostatin, or camptothecin. While SelH mRNA expression was induced by H2O2 treatment, SelH-GFP did not mobilize to sites of oxidative DNA damage. The glutathione level was lower in SelH shRNA than scrambled shRNA HeLa cells, and the H2O2-induced cell death was rescued in the presence of N-acetylcysteine, a glutathione precursor. Altogether, SelH protects against cellular senescence to oxidative stress through a genome maintenance pathway involving ATM and p53.

  20. 7 CFR 301.75-6 - Interstate movement of regulated nursery stock from a quarantined area.

    Science.gov (United States)

    2010-01-01

    ... (Continued) ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE DOMESTIC QUARANTINE NOTICES Citrus Canker Notice of Quarantine and Regulations § 301.75-6 Interstate movement of regulated nursery... from a quarantined area into any area of the United States except commercial citrus-producing areas...

  1. 77 FR 19544 - Regulated Navigation Area, Zidell Waterfront Property, Willamette River, OR

    Science.gov (United States)

    2012-04-02

    ... shipbuilding and dismantling, scrap metal operations, wire burning, aluminum smelting, and housing construction... will not limit vessels from transiting or using the waters covered, except for activities that may...) Regulated Navigation Area. The following area is a regulated navigation area: All waters within the...

  2. 104 Bank Regulation and Reforms: For What? Rural Areas ...

    African Journals Online (AJOL)

    User

    2011-07-21

    Jul 21, 2011 ... Bank regulation and reforms include the 1952 Banking Ordinance amended .... 25 billion; the code for corporate governance; the adoption of risk- based ... accounting practices (Amadasu and Iyoha, 2006; webstite,2005 ;.

  3. Negative Regulation of STAT3 Protein-mediated Cellular Respiration by SIRT1 Protein

    DEFF Research Database (Denmark)

    Bernier, Michel; Paul, Rajib K; Martin-Montalvo, Alejandro;

    2011-01-01

    In mammals, the transcriptional activity of signal transducer and activator of transcription 3 (STAT3) is regulated by the deacetylase SIRT1. However, whether the newly described nongenomic actions of STAT3 toward mitochondrial oxidative phosphorylation are dependent on SIRT1 is unclear....... In this study, Sirt1 gene knock-out murine embryonic fibroblast (MEF) cells were used to delineate the role of SIRT1 in the regulation of STAT3 mitochondrial function. Here, we show that STAT3 mRNA and protein levels and the accumulation of serine-phosphorylated STAT3 in mitochondria were increased...... significantly in Sirt1-KO cells as compared with wild-type MEFs. Various mitochondrial bioenergetic parameters, such as the oxygen consumption rate in cell cultures, enzyme activities of the electron transport chain complexes in isolated mitochondria, and production of ATP and lactate, indicated that Sirt1-KO...

  4. Stimulation of polyunsaturated fatty acid oxidation in myocytes by regulating its cellular uptake

    Energy Technology Data Exchange (ETDEWEB)

    Abdel-aleem, S.; Frangakis, C. (Glaxo Inc., Research Triangle Park, NC (USA)); Badr, M. (Univ. of Missouri-Kansas City, MO (USA))

    1991-01-01

    In order to investigate the regulation of polyunsaturated fatty acid oxidation in the heart, the effect of the phosphodiesterase inhibitor enoximone on the oxidation of (1-{sup 14}C) arachidonic acid, and (1-{sup 14}C) arachidonyl-CoA, were studied in adult rat myocytes, and isolated rat heart mitochondria. Enoximone stimulated arachidonate oxidation by 94%, at a concentration of 0.25 mM. The apparent Vmax value of archidonate oxidation in the presence of enoximone was approximately 75% higher than the value observed with the control in isolated myocytes. Also, enoximone stimulated arachidonate uptake by 27% at a concentration of 0.25 mM. On the other hand, enoximone had no effect on the oxidation of (1-{sup 14}C) arachidonyl-CoA in isolated rat heart mitochondria. These results suggest that the oxidation of polyunsaturated fatty acids in myocytes is regulated by the rate of uptake of these acids across sarcolemmal membranes.

  5. Diurnal Regulation of Cellular Processes in the Cyanobacterium Synechocystis sp. Strain PCC 6803: Insights from Transcriptomic, Fluxomic, and Physiological Analyses.

    Science.gov (United States)

    Saha, Rajib; Liu, Deng; Hoynes-O'Connor, Allison; Liberton, Michelle; Yu, Jingjie; Bhattacharyya-Pakrasi, Maitrayee; Balassy, Andrea; Zhang, Fuzhong; Moon, Tae Seok; Maranas, Costas D; Pakrasi, Himadri B

    2016-05-03

    Synechocystis sp. strain PCC 6803 is the most widely studied model cyanobacterium, with a well-developed omics level knowledgebase. Like the lifestyles of other cyanobacteria, that of Synechocystis PCC 6803 is tuned to diurnal changes in light intensity. In this study, we analyzed the expression patterns of all of the genes of this cyanobacterium over two consecutive diurnal periods. Using stringent criteria, we determined that the transcript levels of nearly 40% of the genes in Synechocystis PCC 6803 show robust diurnal oscillating behavior, with a majority of the transcripts being upregulated during the early light period. Such transcripts corresponded to a wide array of cellular processes, such as light harvesting, photosynthetic light and dark reactions, and central carbon metabolism. In contrast, transcripts of membrane transporters for transition metals involved in the photosynthetic electron transport chain (e.g., iron, manganese, and copper) were significantly upregulated during the late dark period. Thus, the pattern of global gene expression led to the development of two distinct transcriptional networks of coregulated oscillatory genes. These networks help describe how Synechocystis PCC 6803 regulates its metabolism toward the end of the dark period in anticipation of efficient photosynthesis during the early light period. Furthermore, in silico flux prediction of important cellular processes and experimental measurements of cellular ATP, NADP(H), and glycogen levels showed how this diurnal behavior influences its metabolic characteristics. In particular, NADPH/NADP(+) showed a strong correlation with the majority of the genes whose expression peaks in the light. We conclude that this ratio is a key endogenous determinant of the diurnal behavior of this cyanobacterium. Cyanobacteria are photosynthetic microbes that use energy from sunlight and CO2 as feedstock. Certain cyanobacterial strains are amenable to facile genetic manipulation, thus enabling

  6. Cellular mechanisms and behavioral consequences of Kv1.2 regulation in the rat cerebellum

    Science.gov (United States)

    Williams, Michael R; Fuchs, Jason R; Green, John T; Morielli, Anthony D

    2012-01-01

    The potassium channel Kv1.2 alpha-subunit is expressed in cerebellar Purkinje cell (PC) dendrites where its pharmacological inhibition increases excitability (Khavandgar et al., 2005). Kv1.2 is also expressed in cerebellar basket cell (BC) axon terminals (Sheng et al., 1994), where its blockade increases BC inhibition of PCs (Southan and Robertson, 1998a). Secretin receptors are also expressed both in PC dendrites and BC axon terminals (reviewed in (Yuan et al.). The effect of secretin on PC excitability is not yet known, but, like Kv1.2 inhibitors, secretin potently increases inhibitory input to PCs (Yung et al., 2001). This suggests secretin may act in part by suppressing Kv1.2. Receptor-mediated endocytosis is a mechanism of Kv1.2 suppression (Nesti et al., 2004). This process can be regulated by protein kinase A (PKA) (Connors et al., 2008). Since secretin receptors activate PKA (Wessels-Reiker et al., 1993), we tested the hypothesis that secretin regulates Kv1.2 trafficking in the cerebellum. Using cell surface protein biotinylation of rat cerebellar slices, we found secretin decreased cell-surface Kv1.2 levels by modulating Kv1.2 endocytic trafficking. This effect was mimicked by activating adenylate cyclase (AC) with forskolin, and was blocked by pharmacological inhibitors of AC or PKA. Imaging studies identified the BC axon terminal and Purkinje cell dendrites as loci of AC-dependent Kv1.2 trafficking. The physiological significance of secretin regulated Kv1.2 endocytosis is supported by our finding that infusion into the cerebellar cortex of either the Kv1.2 inhibitor Tityustoxin-Kα, or of the Kv1.2 regulator secretin, significantly enhances acquisition of eyeblink conditioning in rats. PMID:22764231

  7. Cell Cycle Regulates Nuclear Stability of AID and Determines the Cellular Response to AID.

    Directory of Open Access Journals (Sweden)

    Quy Le

    2015-09-01

    Full Text Available AID (Activation Induced Deaminase deaminates cytosines in DNA to initiate immunoglobulin gene diversification and to reprogram CpG methylation in early development. AID is potentially highly mutagenic, and it causes genomic instability evident as translocations in B cell malignancies. Here we show that AID is cell cycle regulated. By high content screening microscopy, we demonstrate that AID undergoes nuclear degradation more slowly in G1 phase than in S or G2-M phase, and that mutations that affect regulatory phosphorylation or catalytic activity can alter AID stability and abundance. We directly test the role of cell cycle regulation by fusing AID to tags that destabilize nuclear protein outside of G1 or S-G2/M phases. We show that enforced nuclear localization of AID in G1 phase accelerates somatic hypermutation and class switch recombination, and is well-tolerated; while nuclear AID compromises viability in S-G2/M phase cells. We identify AID derivatives that accelerate somatic hypermutation with minimal impact on viability, which will be useful tools for engineering genes and proteins by iterative mutagenesis and selection. Our results further suggest that use of cell cycle tags to regulate nuclear stability may be generally applicable to studying DNA repair and to engineering the genome.

  8. Cell Cycle Regulates Nuclear Stability of AID and Determines the Cellular Response to AID.

    Directory of Open Access Journals (Sweden)

    Quy Le

    2015-09-01

    Full Text Available AID (Activation Induced Deaminase deaminates cytosines in DNA to initiate immunoglobulin gene diversification and to reprogram CpG methylation in early development. AID is potentially highly mutagenic, and it causes genomic instability evident as translocations in B cell malignancies. Here we show that AID is cell cycle regulated. By high content screening microscopy, we demonstrate that AID undergoes nuclear degradation more slowly in G1 phase than in S or G2-M phase, and that mutations that affect regulatory phosphorylation or catalytic activity can alter AID stability and abundance. We directly test the role of cell cycle regulation by fusing AID to tags that destabilize nuclear protein outside of G1 or S-G2/M phases. We show that enforced nuclear localization of AID in G1 phase accelerates somatic hypermutation and class switch recombination, and is well-tolerated; while nuclear AID compromises viability in S-G2/M phase cells. We identify AID derivatives that accelerate somatic hypermutation with minimal impact on viability, which will be useful tools for engineering genes and proteins by iterative mutagenesis and selection. Our results further suggest that use of cell cycle tags to regulate nuclear stability may be generally applicable to studying DNA repair and to engineering the genome.

  9. Cellular contractility and extracellular matrix stiffness regulate matrix metalloproteinase activity in pancreatic cancer cells.

    Science.gov (United States)

    Haage, Amanda; Schneider, Ian C

    2014-08-01

    The pathogenesis of cancer is often driven by local invasion and metastasis. Recently, mechanical properties of the tumor microenvironment have been identified as potent regulators of invasion and metastasis, while matrix metalloproteinases (MMPs) are classically known as significant enhancers of cancer cell migration and invasion. Here we have been able to sensitively measure MMP activity changes in response to specific extracellular matrix (ECM) environments and cell contractility states. Cells of a pancreatic cancer cell line, Panc-1, up-regulate MMP activities between 3- and 10-fold with increased cell contractility. Conversely, they down-regulate MMP activities when contractility is blocked to levels seen with pan-MMP activity inhibitors. Similar, albeit attenuated, responses are seen in other pancreatic cancer cell lines, BxPC-3 and AsPC-1. In addition, MMP activity was modulated by substrate stiffness, collagen gel concentration, and the degree of collagen cross-linking, when cells were plated on collagen gels ranging from 0.5 to 5 mg/ml that span the physiological range of substrate stiffness (50-2000 Pa). Panc-1 cells showed enhanced MMP activity on stiffer substrates, whereas BxPC-3 and AsPC-1 cells showed diminished MMP activity. In addition, eliminating heparan sulfate proteoglycans using heparinase completely abrogated the mechanical induction of MMP activity. These results demonstrate the first functional link between MMP activity, contractility, and ECM stiffness and provide an explanation as to why stiffer environments result in enhanced cell migration and invasion.

  10. Molecular and cellular aspects and regulation of intestinal lactase-phlorizin hydrolase.

    Science.gov (United States)

    Naim, H Y

    2001-04-01

    Carbohydrates are hydrolyzed in the intestinal lumen by specific enzymes to monosaccharides before transport across the brush border membrane of epithelial cells into the cell interior. The enzymes implicated in the digestion of carbohydrates in the intestinal lumen are membrane-bound glycoproteins that are expressed at the apical domain of the enterocytes. Absent or reduced activity of one of these enzymes is the cause of disaccharide intolerance and malabsorption, the symptoms of which are abdominal pain, cramps or distention, flatulence, nausea and osmotic diarrhea. Lactose intolerance is the most common intestinal disorder that is associated with an absence or drastically reduced levels of an intestinal enzyme, in this case lactase-phlorizin hydrolase (LPH). The pattern of reduction of activity has been termed late onset of lactase deficiency or adult type hypolactasia. It was thought that the regulation of LPH was post-translational and was associated with altered structural features of the enzyme. Recent studies, however, suggest that the major mechanism of regulation of LPH is transcriptional. Other forms of lactose intolerance include the rare congenital lactase deficiency and secondary forms, such as those caused by mucosal injury, due to infectious gastroenteritis, celiac disease, parasitic infection, drug-induced enteritis and Crohn's disease. This review will shed light on important strucural and biosynthetic aspects of LPH, the role played by particular regions of the LPH protein in its transport, polarized sorting, and function, as well as on the gene expession and regulation of the activity of the enzyme.

  11. Exploring key cellular processes and candidate genes regulating the primary thickening growth of Moso underground shoots.

    Science.gov (United States)

    Wei, Qiang; Jiao, Chen; Guo, Lin; Ding, Yulong; Cao, Junjie; Feng, Jianyuan; Dong, Xiaobo; Mao, Linyong; Sun, Honghe; Yu, Fen; Yang, Guangyao; Shi, Peijian; Ren, Guodong; Fei, Zhangjun

    2017-04-01

    The primary thickening growth of Moso (Phyllostachys edulis) underground shoots largely determines the culm circumference. However, its developmental mechanisms remain largely unknown. Using an integrated anatomy, mathematics and genomics approach, we systematically studied cellular and molecular mechanisms underlying the growth of Moso underground shoots. We discovered that the growth displayed a spiral pattern and pith played an important role in promoting the primary thickening process of Moso underground shoots and driving the evolution of culms with different sizes among different bamboo species. Different with model plants, the shoot apical meristem (SAM) of Moso is composed of six layers of cells. Comparative transcriptome analysis identified a large number of genes related to the vascular tissue formation that were significantly upregulated in a thick wall variant with narrow pith cavity, mildly spiral growth, and flat and enlarged SAM, including those related to plant hormones and those involved in cell wall development. These results provide a systematic perspective on the primary thickening growth of Moso underground shoots, and support a plausible mechanism resulting in the narrow pith cavity, weak spiral growth but increased vascular bundle of the thick wall Moso. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

  12. Modulating cellular recombination potential through alterations in RecA structure and regulation.

    Science.gov (United States)

    Bakhlanova, Irina V; Dudkina, Alexandra V; Baitin, Dima M; Knight, Kendall L; Cox, Michael M; Lanzov, Vladislav A

    2010-12-01

    The wild-type Escherichia coli RecA protein is a recombinase platform with unrealized recombination potential. We have explored the factors affecting recombination during conjugation with a quantitative assay. Regulatory proteins that affect RecA function have the capacity to increase or decrease recombination frequencies by factors up to sixfold. Autoinhibition by the RecA C-terminus can affect recombination frequency by factors up to fourfold. The greatest changes in recombination frequency measured here are brought about by point mutations in the recA gene. RecA variants can increase recombination frequencies by more than 50-fold. The RecA protein thus possesses an inherently broad functional range. The RecA protein of E. coli (EcRecA) is not optimized for recombination function. Instead, much of the recombination potential of EcRecA is structurally suppressed, probably reflecting cellular requirements. One point mutation in EcRecA with a particularly dramatic effect on recombination frequency, D112R, exhibits an enhanced capacity to load onto SSB-coated ssDNA, overcome the effects of regulatory proteins such as PsiB and RecX, and to pair homologous DNAs. Comparisons of key RecA protein mutants reveal two components to RecA recombination function - filament formation and the inherent DNA pairing activity of the formed filaments.

  13. Temporal regulation of cerebellar EGL migration through a switch in cellular responsiveness to the meninges.

    Science.gov (United States)

    Zhu, Yan; Yu, Tao; Rao, Yi

    2004-03-01

    We have studied the temporal and spatial control of cell migration from the external germinal layer (EGL) in the mammalian cerebellum as a model for cortical migration. Our results have demonstrated that embryonic EGL cells do not migrate into internal layers because they respond to a diffusible attractant in the meninges, the nonneural tissues covering the nervous system, and to a repellent in the neuroepithelium. Two developmental changes are important for postnatal EGL migration: the disappearance of the repellent in the inner layers and a switch in cellular responsiveness of EGL cells so that the postnatal EGL cells respond to the repellent, but not the attractant in the meninges. Besides revealing the signaling role of meninges in cortical development, our study suggests that an active mechanism is required to prevent cell migration, and that mechanisms of cell migration should be studied even in the absence of apparent changes in cell positions. We propose a model for the developmental control of neuronal migration in the cerebellar cortex.

  14. Cellular and molecular regulation of muscle growth and development in meat animals.

    Science.gov (United States)

    Dayton, W R; White, M E

    2008-04-01

    Although in vivo and in vitro studies have established that anabolic steroids, transforming growth factor-beta (TGF-beta), and myostatin affect muscle growth in meat-producing animals, their mechanisms of action are not completely understood. Anabolic steroids have been widely used as growth promoters in feedlot cattle for over 50 yr. A growing body of evidence suggests that increased muscle levels of IGF-I and increased muscle satellite cell numbers play a role in anabolic steroid enhanced muscle growth. In contrast to anabolic steroids, the members of the TGF-beta-myostatin family suppress muscle growth in vivo and suppress both proliferation and differentiation of cultured myogenic cells. Recent evidence suggests that IGFBP-3 and IGFBP-5 play a role in mediating the proliferation-suppressing actions of both TGF-beta and myostatin on cultured myogenic cells. Consequently, this review will focus on the roles of IGF-I and IGFBP in the cellular and molecular mechanisms of action of anabolic steroids and TGF-beta and myostatin, respectively.

  15. 78 FR 72028 - Special Regulations, Areas of the National Park System, Curecanti National Recreation Area...

    Science.gov (United States)

    2013-12-02

    ... disabled or mobility impaired visitors to experience the recreation area. Motor vehicles have traditionally... (ORV) `` reas and trails shall be located in areas of the National Park system, Natural Areas,...

  16. Polyhydroxylated fullerene attenuates oxidative stress-induced apoptosis via a fortifying Nrf2-regulated cellular antioxidant defence system

    Directory of Open Access Journals (Sweden)

    Ye SF

    2014-04-01

    Full Text Available Shefang Ye,1 Min Chen,1 Yuanqin Jiang,1,2 Mingliang Chen,3 Tong Zhou,1 Yange Wang,1 Zhenqing Hou,1 Lei Ren11Department of Biomaterials, Research Center of Biomedical Engineering, College of Materials, Xiamen University, Xiamen, People's Republic of China; 2First Affiliated Hospital of Xiamen University, Xiamen, People's Republic of China; 3Key Laboratory of Marine Biogenetic Resources, Third Institute of Oceanography, State Oceanic Administration, Xiamen, People's Republic of ChinaAbstract: Polyhydroxylated derivatives of fullerene C60, named fullerenols (C60[OH]n, have stimulated great interest because of their potent antioxidant properties in various chemical and biological systems, which enable them to be used as a new promising pharmaceutical for the future treatment of oxidative stress-related diseases, but the details remain unknown. Nuclear factor erythroid 2-related factor 2 (Nrf2 is a principal transcription factor that regulates expression of several antioxidant genes via binding to the antioxidant response element and plays a crucial role in cellular defence against oxidative stress. In this study we investigated whether activation of the Nrf2/antioxidant response element pathway contributes to the cytoprotective effects of C60(OH24. Our results showed that C60(OH24 enhanced nuclear translocation of Nrf2 and upregulated expression of phase II antioxidant enzymes, including heme oxygenase-1 (HO-1, NAD(PH: quinine oxidoreductase 1, and γ-glutamate cysteine ligase in A549 cells. Treatment with C60(OH24 resulted in phosphorylation of p38 mitogen-activated protein kinases (p38 MAPK, extracellular signal-regulated kinases, and c-Jun-N-terminal kinases. By using inhibitors of cellular kinases, we showed that pretreatment of A549 cells with SB203580, a specific inhibitor of p38 MAPK, abolished nuclear translocation of Nrf2 and induction of HO-1 protein induced by C60(OH24, indicating an involvement of p38 MAPK in Nrf2/HO-1 activation by C60

  17. The cellular distribution and Ser262 phosphorylation of tau protein are regulated by BDNF in vitro.

    Directory of Open Access Journals (Sweden)

    Qian Chen

    Full Text Available The brain-enriched microtubule-associated protein tau, a critical regulator of cytoskeletal dynamics, forms insoluble aggregates in a number of neurodegenerative diseases termed tauopathies, including Alzheimer's disease (AD. Hyperphosphorylation of tau protein is an important mechanism for aggregation, so many studies on the pathogenesis of AD and other tauopathies have focused on regulation of tau phosphorylation by kinases and phosphatases. Less studied are mechanisms of tau transcriptional and post-transcriptional regulation by extracellular signals such as BDNF and how such changes alter neuronal function. Previously, we reported that tau is required for morphological plasticity induced by BDNF. Here, we further explore tau modification during BDNF-induced changes in neuronal cell morphology. In undifferentiated SH-SY5Y cells lacking neurites, tau formed a sphere within the soma as revealed by immunocytochemistry. In contrast, tau was enriched in the neurites and sparse in the soma of SH-SY5Y cells induced to differentiate by retinoic acid (RA. Treatment with RA also increased total tau protein levels but decreased expression of tau phosphorylated at Ser262 as determined by Western blot. Both effects were further enhanced by subsequent BDNF treatment. Upregulation of tau protein and downregulation of p-Ser262 tau were correlated with total neurite length (R = .94 and R = -.98, respectively. When primary E18 hippocampal neurons were treated with nocodazole, a blocker of microtubule polymerization, nascent neurites were lost and tau shifted to the soma. This process of retrograde tau movement away from neurites was reversed by BDNF. These results indicate that tau is redistributed to neurites and dephosphorylated during RA- and BDNF-mediated differentiation.

  18. Extracellular Matrix Components Regulate Cellular Polarity and Tissue Structure in the Developing and Mature Retina.

    Science.gov (United States)

    Varshney, Shweta; Hunter, Dale D; Brunken, William J

    2015-01-01

    While genetic networks and other intrinsic mechanisms regulate much of retinal development, interactions with the extracellular environment shape these networks and modify their output. The present review has focused on the role of one family of extracellular matrix molecules and their signaling pathways in retinal development. In addition to their effects on the developing retina, laminins play a role in maintaining Müller cell polarity and compartmentalization, thereby contributing to retinal homeostasis. This article which is intended for the clinical audience, reviews the fundamentals of retinal development, extracellular matrix organization and the role of laminins in retinal development. The role of laminin in cortical development is also briefly discussed.

  19. Extracellular Matrix components regulate cellular polarity and tissue structure in the developing and mature Retina

    Directory of Open Access Journals (Sweden)

    Shweta Varshney

    2015-01-01

    Full Text Available While genetic networks and other intrinsic mechanisms regulate much of retinal development, interactions with the extracellular environment shape these networks and modify their output. The present review has focused on the role of one family of extracellular matrix molecules and their signaling pathways in retinal development. In addition to their effects on the developing retina, laminins play a role in maintaining Müller cell polarity and compartmentalization, thereby contributing to retinal homeostasis. This article which is intended for the clinical audience, reviews the fundamentals of retinal development, extracellular matrix organization and the role of laminins in retinal development. The role of laminin in cortical development is also briefly discussed.

  20. Cellular differentiation regulated by gibberellin in the Arabidopsis thaliana pickle mutant

    Energy Technology Data Exchange (ETDEWEB)

    Ogas, J.; Somerville, C. [Carnegie Institution of Washington, Stanford, CA (United States); Cheng, Jin-Chen; Sung, R. [Univ. of California, Berkeley, CA (United States)

    1997-07-04

    The plant growth regulator gibberellin (GA) has a profound effect on shoot development and promotes developmental transitions such as flowering. Little is known about any analogous effect GA might have on root development. In a screen for mutants, Arabi-dopsis plants carrying a mutation designated pickle (pkl) were isolated in which the primary root meristem retained characteristics of embryonic tissue. Expression of this aberrant differentiation state was suppressed by GA. Root tissue from plants carrying the pkl mutation spontaneously regenerated new embryos and plants. 19 refs., 3 figs., 1 tab.

  1. GASOTRANSMITTERS: FROM THE TOXIC EFFECTS TO THE REGULATION OF CELLULAR FUNCTION AND CLINICAL APPLICATION

    Directory of Open Access Journals (Sweden)

    G. F. Sitdikova

    2014-01-01

    Full Text Available Nitric oxide II (NO, carbon monoxide (СО and hydrogen sulfide (H2S for many decades were described as the toxic gases inducing damaging action in man’s organisms. Recently it was found that NO, CO and H2S endogenously synthesized and served as signaling molecules of autocrine and paracrine regulation in many systems. The properties, mechanisms of synthesis and action in excitable systems are presented in this paper. Besides we also descried our results concerning the effects and mechanisms of action of gaseous messengers in peripheral nervous system – in neuromuscular junction. 

  2. An efficient method for in vitro gene delivery via regulation of cellular endocytosis pathway

    Directory of Open Access Journals (Sweden)

    Luo J

    2015-03-01

    Full Text Available Jing Luo,1,2,* Caixia Li,3,* Jianlin Chen,1,2 Gang Wang,2 Rong Gao,1 Zhongwei Gu2 1Key Laboratory for Bio-Resource and Eco-Environment of Ministry of Education, Key Laboratory for Animal Disease Prevention and Food Safety of Sichuan Province, College of Life Science, Sichuan University, Chengdu, People’s Republic of China; 2National Engineering Research Center for Biomaterials, Sichuan University, Chengdu, People’s Republic of China; 3Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, People’s Republic of China *These authors contributed equally to this work Abstract: Transfection efficiency was the primary goal for in vitro gene delivery mediated by nonviral gene carriers. Here, we report a modified gene transfection method that could greatly increase the efficiency of, and accelerate the process mediated by, 25 kDa branched polyethyleneimine and Lipofectamine™ 2000 in a broad range of cell strains, including tumor, normal, primary, and embryonic stem cells. In this method, the combination of transfection procedure with optimized complexation volume had a determinant effect on gene delivery result. The superiorities of the method were found to be related to the change of cellular endocytosis pathway and decrease of particle size. The efficient and simple method established in this study can be widely used for in vitro gene delivery into cultured cells. We think it may also be applicable for many more nonviral gene delivery materials than polyethyleneimine and liposome. Keywords: gene delivery, gene expression, endocytosis, polyethyleneimine, Lipofectamine™ 2000

  3. OCT4B1 Regulates the Cellular Stress Response of Human Dental Pulp Cells with Inflammation

    Directory of Open Access Journals (Sweden)

    Lu Liu

    2017-01-01

    Full Text Available Introduction. Infection and apoptosis are combined triggers for inflammation in dental tissues. Octamer-binding transcription factor 4-B1 (OCT4B1, a novel spliced variant of OCT4 family, could respond to the cellular stress and possess antiapoptotic property. However, its specific role in dental pulpitis remains unknown. Methods. To investigate the effect of OCT4B1 on inflammation of dental pulp cells (DPCs, its expression in inflamed dental pulp tissues and DPCs was examined by in situ hybridization, real-time PCR, and FISH assay. OCT4B1 overexpressed DPCs model was established, confirmed by western blot and immunofluorescence staining, and then stimulated with Lipopolysaccharide (LPS. Apoptotic rate was determined by Hoechst/PI staining and FACS. Cell survival rate was calculated by CCK8 assay. Results. In situ hybridization, real-time PCR, and FISH assay revealed that OCT4B1 was extensively expressed in inflamed dental pulp tissues and DPCs with LPS stimulation. Western blot and immunofluorescence staining showed the expression of OCT4B1 and OCT4B increased after OCT4B1 transfection. Hoechst/PI staining and FACS demonstrated that less red/blue fluorescence was detected and apoptotic percentage decreased (3.45% after transfection. CCK8 demonstrated that the survival rate of pCDH-OCT4B1-flag cells increased. Conclusions. OCT4B1 plays an essential role in inflammation and apoptosis of DPCs. OCT4B might operate synergistically with OCT4B1 to reduce apoptosis.

  4. 78 FR 4788 - Regulated Navigation Area; Reporting Requirements for Barges Loaded With Certain Dangerous...

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    2013-01-23

    ... under section 4(a) of the Administrative Procedure Act (APA) (5 U.S.C. 553(b)). This provision... follows: PART 165--REGULATED NAVIGATION AREAS AND LIMITED ACCESS AREAS 0 1. The authority citation...

  5. Diurnal Regulation of Cellular Processes in the Cyanobacterium Synechocystis sp. Strain PCC 6803: Insights from Transcriptomic, Fluxomic, and Physiological Analyses

    Directory of Open Access Journals (Sweden)

    Rajib Saha

    2016-05-01

    Full Text Available Synechocystis sp. strain PCC 6803 is the most widely studied model cyanobacterium, with a well-developed omics level knowledgebase. Like the lifestyles of other cyanobacteria, that of Synechocystis PCC 6803 is tuned to diurnal changes in light intensity. In this study, we analyzed the expression patterns of all of the genes of this cyanobacterium over two consecutive diurnal periods. Using stringent criteria, we determined that the transcript levels of nearly 40% of the genes in Synechocystis PCC 6803 show robust diurnal oscillating behavior, with a majority of the transcripts being upregulated during the early light period. Such transcripts corresponded to a wide array of cellular processes, such as light harvesting, photosynthetic light and dark reactions, and central carbon metabolism. In contrast, transcripts of membrane transporters for transition metals involved in the photosynthetic electron transport chain (e.g., iron, manganese, and copper were significantly upregulated during the late dark period. Thus, the pattern of global gene expression led to the development of two distinct transcriptional networks of coregulated oscillatory genes. These networks help describe how Synechocystis PCC 6803 regulates its metabolism toward the end of the dark period in anticipation of efficient photosynthesis during the early light period. Furthermore, in silico flux prediction of important cellular processes and experimental measurements of cellular ATP, NADP(H, and glycogen levels showed how this diurnal behavior influences its metabolic characteristics. In particular, NADPH/NADP+ showed a strong correlation with the majority of the genes whose expression peaks in the light. We conclude that this ratio is a key endogenous determinant of the diurnal behavior of this cyanobacterium.

  6. Cellular Cholesterol Regulates Ubiquitination and Degradation of the Cholesterol Export Proteins ABCA1 and ABCG1*

    Science.gov (United States)

    Hsieh, Victar; Kim, Mi-Jurng; Gelissen, Ingrid C.; Brown, Andrew J.; Sandoval, Cecilia; Hallab, Jeannette C.; Kockx, Maaike; Traini, Mathew; Jessup, Wendy; Kritharides, Leonard

    2014-01-01

    The objective of this study was to examine the influence of cholesterol in post-translational control of ABCA1 and ABCG1 protein expression. Using CHO cell lines stably expressing human ABCA1 or ABCG1, we observed that the abundance of these proteins is increased by cell cholesterol loading. The response to increased cholesterol is rapid, is independent of transcription, and appears to be specific for these membrane proteins. The effect is mediated through cholesterol-dependent inhibition of transporter protein degradation. Cell cholesterol loading similarly regulates degradation of endogenously expressed ABCA1 and ABCG1 in human THP-1 macrophages. Turnover of ABCA1 and ABCG1 is strongly inhibited by proteasomal inhibitors and is unresponsive to inhibitors of lysosomal proteolysis. Furthermore, cell cholesterol loading inhibits ubiquitination of ABCA1 and ABCG1. Our findings provide evidence for a rapid, cholesterol-dependent, post-translational control of ABCA1 and ABCG1 protein levels, mediated through a specific and sterol-sensitive mechanism for suppression of transporter protein ubiquitination, which in turn decreases proteasomal degradation. This provides a mechanism for acute fine-tuning of cholesterol transporter activity in response to fluctuations in cell cholesterol levels, in addition to the longer term cholesterol-dependent transcriptional regulation of these genes. PMID:24500716

  7. PKR is activated by cellular dsRNAs during mitosis and acts as a mitotic regulator.

    Science.gov (United States)

    Kim, Yoosik; Lee, Jung Hyun; Park, Jong-Eun; Cho, Jun; Yi, Hyerim; Kim, V Narry

    2014-06-15

    dsRNA-dependent protein kinase R (PKR) is a ubiquitously expressed enzyme well known for its roles in immune response. Upon binding to viral dsRNA, PKR undergoes autophosphorylation, and the phosphorylated PKR (pPKR) regulates translation and multiple signaling pathways in infected cells. Here, we found that PKR is activated in uninfected cells, specifically during mitosis, by binding to dsRNAs formed by inverted Alu repeats (IRAlus). While PKR and IRAlu-containing RNAs are segregated in the cytosol and nucleus of interphase cells, respectively, they interact during mitosis when nuclear structure is disrupted. Once phosphorylated, PKR suppresses global translation by phosphorylating the α subunit of eukaryotic initiation factor 2 (eIF2α). In addition, pPKR acts as an upstream kinase for c-Jun N-terminal kinase and regulates the levels of multiple mitotic factors such as cyclins A and B and Polo-like kinase 1 and phosphorylation of histone H3. Disruption of PKR activation via RNAi or expression of a transdominant-negative mutant leads to misregulation of the mitotic factors, delay in mitotic progression, and defects in cytokinesis. Our study unveils a novel function of PKR and endogenous dsRNAs as signaling molecules during the mitosis of uninfected cells.

  8. The dynamics of Turing patterns for morphogen-regulated growing domains with cellular response delays.

    Science.gov (United States)

    Seirin Lee, S; Gaffney, E A; Baker, R E

    2011-11-01

    Since its conception in 1952, the Turing paradigm for pattern formation has been the subject of numerous theoretical investigations. Experimentally, this mechanism was first demonstrated in chemical reactions over 20 years ago and, more recently, several examples of biological self-organisation have also been implicated as Turing systems. One criticism of the Turing model is its lack of robustness, not only with respect to fluctuations in the initial conditions, but also with respect to the inclusion of delays in critical feedback processes such as gene expression. In this work we investigate the possibilities for Turing patterns on growing domains where the morphogens additionally regulate domain growth, incorporating delays in the feedback between signalling and domain growth, as well as gene expression. We present results for the proto-typical Schnakenberg and Gierer-Meinhardt systems: exploring the dynamics of these systems suggests a reconsideration of the basic Turing mechanism for pattern formation on morphogen-regulated growing domains as well as highlighting when feedback delays on domain growth are important for pattern formation.

  9. Intra-cellular mechanism of Anti-Müllerian hormone (AMH) in regulation of follicular development.

    Science.gov (United States)

    Hayes, Emily; Kushnir, Vitaly; Ma, Xiaoting; Biswas, Anindita; Prizant, Hen; Gleicher, Norbert; Sen, Aritro

    2016-09-15

    Anti-Müllerian hormone (AMH) is a member of the transforming growth factor-β superfamily and plays a crucial role in testicular and ovarian functions. In clinical practice, AMH is used as a diagnostic and/or prognostic marker in women in association with ovulation induction and in various pathophysiological conditions. Despite widespread clinical use of AMH, our mechanistic understanding of AMH actions in regulating follicular development is limited. Using a mouse model, we in this study report that in vivo AMH treatment while stalls follicular development and inhibits ovulation, also prevents follicular atresia. We further show that these AMH actions are mediated through induction of two miRNAs, miR-181a and miR-181b, which regulate various aspects of FSH signaling and follicular growth, ultimately affecting downstream gene expression and folliculogenesis. We also report that in this mouse model AMH pre-treatment prior to superovulation improves oocyte yield. These studies, therefore, offer new mechanistic insight into AMH actions in folliculogenesis and point toward potential utilization of AMH as a therapeutic agent.

  10. Copper transporters regulate the cellular pharmacology and sensitivity to Pt drugs.

    Science.gov (United States)

    Safaei, Roohangiz; Howell, Stephen B

    2005-01-01

    Recent studies have demonstrated that the major Cu influx transporter CTR1 regulates tumor cell uptake of cisplatin (DDP), carboplatin (CBDCA) and oxaliplatin (L-OHP), and that the two Cu efflux transporters ATP7A and ATP7B regulate the efflux of these drugs. Evidence for the concept that these platinum (Pt) drugs enter cells and are distributed to various subcellular compartments via transporters that have evolved to manage Cu homeostasis includes the demonstration of: (1) bidirectional cross-resistance between cells selected for resistance to either the Pt drugs or Cu; (2) parallel changes in the transport of Pt and Cu drugs in resistant cells; (3) altered cytotoxic sensitivity and Pt drug accumulation in cells transfected with Cu transporters; and (4) altered expression of Cu transporters in Pt drug-resistant tumors. Appreciation of the role of the Cu transporters in the development of resistance to DDP, CBDCA, and L-OHP offers novel insights into strategies for preventing or reversing resistance to this very important family of anticancer drugs.

  11. Sub-cellular mRNA localization modulates the regulation of gene expression by small RNAs in bacteria

    Science.gov (United States)

    Teimouri, Hamid; Korkmazhan, Elgin; Stavans, Joel; Levine, Erel

    2017-10-01

    Small non-coding RNAs can exert significant regulatory activity on gene expression in bacteria. In recent years, substantial progress has been made in understanding bacterial gene expression by sRNAs. However, recent findings that demonstrate that families of mRNAs show non-trivial sub-cellular distributions raise the question of how localization may affect the regulatory activity of sRNAs. Here we address this question within a simple mathematical model. We show that the non-uniform spatial distributions of mRNA can alter the threshold-linear response that characterizes sRNAs that act stoichiometrically, and modulate the hierarchy among targets co-regulated by the same sRNA. We also identify conditions where the sub-cellular organization of cofactors in the sRNA pathway can induce spatial heterogeneity on sRNA targets. Our results suggest that under certain conditions, interpretation and modeling of natural and synthetic gene regulatory circuits need to take into account the spatial organization of the transcripts of participating genes.

  12. 76 FR 3489 - Revision of American Viticultural Area Regulations

    Science.gov (United States)

    2011-01-20

    ... on February 22, 2011. FOR FURTHER INFORMATION CONTACT: Rita D. Butler, Regulations and Rulings... State Assembly, ``as a statement of the California Legislature's concern and opposition to'' Notice Nos. 77 and 78. She further stated that the ``Senate and the Assembly of the State of California,...

  13. El nucléolo como un regulador del envejecimiento celular The nucleolus as a regulator of cellular senescence

    Directory of Open Access Journals (Sweden)

    María Rosete

    2007-04-01

    Full Text Available El nucléolo, considerado únicamente como el sitio de síntesis de los ribosomas, actualmente representa una estructura nuclear dinámica que participa en la regulación de importantes procesos celulares. Numerosas evidencias han demostrado que el envejecimiento celular es una de las diversas funciones que son controladas por el nucléolo. Las mutaciones en las proteínas de localización nucleolar promueven el envejecimiento prematuro en levaduras y humanos. La carencia de represión en la transcripción de genes que codifican para el ARNr que se encuentran dañados, y las mutaciones en las helicasas del ADN encargadas de minimizar la formación de círculos extra-cromosómicos del ADN que codifica para el ARNr, provocan modificaciones en la estructura del nucléolo e inducen envejecimiento prematuro en levaduras. De igual manera, en los humanos la carencia de las helicasas del ADN localizadas en el nucléolo y que participan en el mantenimiento de la integridad genómica, favorecen el desarrollo de aquellas enfermedades asociadas con el envejecimiento acelerado. Además, la presencia de algunos componentes de la telomerasa en el nucléolo, indica que parte de la biosíntesis de esta enzima se realiza en esta estructura nuclear, sugiriendo una conexión entre el nucléolo y la síntesis de los telómeros en la regulación del envejecimiento celular. Por otra parte, el nucléolo secuestra proteínas para regular su actividad biológica durante el inicio o término de la vida replicativa celular.The nucleolus has been considered originally only as the site for the ribosome synthesis, but now it is well known that it represents a dynamic nuclear structure involved in important cellular processes. Several evidences have demonstrated that the nucleolus regulates the cellular senescence. Specific mutations on the DNAs codifying for nucleolar proteins induced premature senescence from yeast to human. The failure to repress the genes transcription

  14. Inhibitory Effect of 1,8-Cineol on β-Catenin Regulation, WNT11 Expression, and Cellular Progression in HNSCC

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    Anna Roettger

    2017-05-01

    Full Text Available ObjectivesHead and neck squamous cell carcinoma (HNSCC is one of the most common tumors worldwide. The high mortality rates have not changed during the last three decades, and thus there is an enormous need for innovative therapy approaches. Several recent studies suggest an important role of the Wnt/β-catenin signaling pathway in the tumorigenesis of HNSCC. We analyzed the effect of the monoterpene oxide 1,8-cineol on the regulation of the Wnt/β-catenin signaling pathway and the cellular progression of different HNSCC cell lines.MethodsPermanent HNSCC cell lines were exposed to varying concentrations and times of 1,8-cineol. Regulation and activity profiles of the Wnt/β-catenin signaling cascade were analyzed using Western hybridization experiments, MTT assays, real-time PCR-based epithelial to mesenchymal transition array, and immunohistochemistry.ResultsExposure of different cell lines to 1,8-cineol treatment resulted in a dose-dependent inhibition of proliferation and a decreased activity of the WNT/β-catenin pathway. We can show the inhibition of glycogen synthase kinase 3 (GSK-3α/β (Ser-9/21 as well as a corresponding decreased endolysosomal localization, leading to a decreased β-catenin activity. Furthermore, we can show that exposure to cineol functionally results in a reduced expression of WNT11.ConclusionIn this work, we demonstrate for the first time that 1,8-cineol acts as an inhibitor of the Wnt/β-catenin activity in HNSCC via a decreased inhibition of GSK-3, which lead to reduced levels of WNT11 and a dose-dependent decrease of the cellular progression. Our data represent a new mechanism of 1,8-cineol activity, which may lead to novel molecular targets and treatment approaches of this natural drug.

  15. Cellular transcripts regulated during infections with Highly Pathogenic H5N1 Avian Influenza virus in 3 host systems

    Directory of Open Access Journals (Sweden)

    Noor Suriani M

    2011-04-01

    Full Text Available Abstract Background Highly pathogenic Avian Influenza (HPAI virus is able to infect many hosts and the virus replicates in high levels in the respiratory tract inducing severe lung lesions. The pathogenesis of the disease is actually the outcome of the infection as determined by complex host-virus interactions involving the functional kinetics of large numbers of participating genes. Understanding the genes and proteins involved in host cellular responses are therefore, critical for the elucidation of the mechanisms of infection. Methods Differentially expressed transcripts regulated in a H5N1 infections of whole lung organ of chicken, in-vitro chick embryo lung primary cell culture (CeLu and a continuous Madin Darby Canine Kidney cell line was undertaken. An improved mRNA differential display technique (Gene Fishing™ using annealing control primers that generates reproducible, authentic and long PCR products that are detectable on agarose gels was used for the identification of differentially expressed genes (DEGs. Seven of the genes have been selected for validation using a TaqMan® based real time quantitative PCR assay. Results Thirty seven known and unique differentially expressed genes from lungs of chickens, CeLu and MDCK cells were isolated. Among the genes isolated and identified include heat shock proteins, Cyclin D2, Prenyl (decaprenyl diphosphate synthase, IL-8 and many other unknown genes. The quantitative real time RT-PCR assay data showed that the transcription kinetics of the selected genes were clearly altered during infection by the Highly Pathogenic Avian Influenza virus. Conclusion The Gene Fishing™ technique has allowed for the first time, the isolation and identification of sequences of host cellular genes regulated during H5N1 virus infection. In this limited study, the differentially expressed genes in the three host systems were not identical, thus suggesting that their responses to the H5N1 infection may not share

  16. Interactions between HIF-1α and AMPK in the regulation of cellular hypoxia adaptation in chronic kidney disease.

    Science.gov (United States)

    Li, Hui; Satriano, Joseph; Thomas, Joanna L; Miyamoto, Satoshi; Sharma, Kumar; Pastor-Soler, Núria M; Hallows, Kenneth R; Singh, Prabhleen

    2015-09-01

    Renal hypoxia contributes to chronic kidney disease (CKD) progression, as validated in experimental and human CKD. In the early stages, increased oxygen consumption causes oxygen demand/supply mismatch, leading to hypoxia. Hence, early targeting of the determinants and regulators of oxygen consumption in CKD may alter the disease course before permanent damage ensues. Here, we focus on hypoxia inducible factor-1α (HIF-1α) and AMP-activated protein kinase (AMPK) and on the mechanisms by which they may facilitate cellular hypoxia adaptation. We found that HIF-1α activation in the subtotal nephrectomy (STN) model of CKD limits protein synthesis, inhibits apoptosis, and activates autophagy, presumably for improved cell survival. AMPK activation was diminished in the STN kidney and was remarkably restored by HIF-1α activation, demonstrating a novel role for HIF-1α in the regulation of AMPK activity. We also investigated the independent and combined effects of HIF-1α and AMPK on cell survival and death pathways by utilizing pharmacological and knockdown approaches in cell culture models. We found that the effect of HIF-1α activation on autophagy is independent of AMPK, but on apoptosis it is partially AMPK dependent. The effects of HIF-1α and AMPK activation on inhibiting protein synthesis via the mTOR pathway appear to be additive. These various effects were also observed under hypoxic conditions. In conclusion, HIF-1α and AMPK appear to be linked at a molecular level and may act as components of a concerted cellular response to hypoxic stress in the pathophysiology of CKD.

  17. Testicular disorders induced by plant growth regulators: cellular protection with proanthocyanidins grape seeds extract.

    Science.gov (United States)

    Hassan, Hanaa A; Isa, Ahmed M; El-Kholy, Wafaa M; Nour, Samar E

    2013-10-01

    The present study aims to investigate the adverse effects of plant growth regulators : gibberellic acid (GA3) and indoleacetic acid (IAA) on testicular functions in rats, and extends to investigate the possible protective role of grape seed extract, proanthocyanidin (PAC). Male rats were divided into six groups; control group, PAC, GA3, IAA, GA3 + PAC and IAA + PAC groups. The data showed that GA3 and IAA caused significant increase in total lipids, total cholesterol, triglycerides, phospholipids and low-density-lipoprotein cholesterol in the serum, concomitant with a significant decrease in high-density-lipoprotein cholesterol, total protein, and testosterone levels. In addition, there was significant decrease in the activity of alkaline phosphatase, acid phosphatase, and gamma-glutamyl transferase. A significant decrease was detected also in epididymyal fructose along with a significant reduction in sperm count. Testicular lipid peroxidation product and hydrogen peroxide (H2O2) levels were significantly increased. Meanwhile, the total antioxidant capacity, glutathione, sulphahydryl group content, as well as superoxide dismutase, catalase, and glucose-6-phosphate dehydrogenase activity were significantly decreased. Moreover, there were a number of histopathological testicular changes including Leydig's cell degeneration, reduction in seminiferous tubule and necrotic symptoms and sperm degeneration in both GA3- and IAA-treated rats. However, an obvious recovery of all the above biochemical and histological testicular disorders was detected when PAC seed extract was supplemented to rats administered with GA3 or IAA indicating its protective effect. Therefore it was concluded that supplementation with PAC had ameliorative effects on those adverse effects of the mentioned plant growth regulators through its natural antioxidant properties.

  18. STRAP regulates c-Jun ubiquitin-mediated proteolysis and cellular proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Reiner, Jennifer [Department of Cancer Biology, Vanderbilt University, School of Medicine, Nashville, TN (United States); Ye, Fei [Department of Biostatistics, Vanderbilt University, School of Medicine, Nashville, TN (United States); Kashikar, Nilesh D. [Department of Cancer Biology, Vanderbilt University, School of Medicine, Nashville, TN (United States); Datta, Pran K., E-mail: pran.datta@vanderbilt.edu [Department of Cancer Biology, Vanderbilt University, School of Medicine, Nashville, TN (United States); Department of Surgery, Vanderbilt University, School of Medicine, Nashville, TN (United States)

    2011-04-08

    Highlights: {yields} STRAP is specifically correlated with c-Jun expression and activation in fibroblasts. {yields} STRAP inhibits c-Jun ubiquitylation in vivo and prolongs the half-life of c-Jun. {yields} STRAP expression increases expression of the AP-1 target gene, cyclin D1, and promotes cell autonomous growth. -- Abstract: STRAP is a ubiquitous WD40 protein that has been implicated in tumorigenesis. Previous studies suggest that STRAP imparts oncogenic characteristics to cells by promoting ERK and pRb phosphorylation. While these findings suggest that STRAP can activate mitogenic signaling pathways, the effects of STRAP on other MAPK pathways have not been investigated. Herein, we report that STRAP regulates the expression of the c-Jun proto-oncogene in mouse embryonic fibroblasts. Loss of STRAP expression results in reduced phospho-c-Jun and total c-Jun but does not significantly reduce the level of two other early response genes, c-Myc and c-Fos. STRAP knockout also decreases expression of the AP-1 target gene, cyclin D1, which is accompanied by a reduction in cell growth. No significant differences in JNK activity or basal c-Jun mRNA levels were observed between wild type and STRAP null fibroblasts. However, proteasomal inhibition markedly increases c-Jun expression in STRAP knockout MEFs and STRAP over-expression decreases the ubiquitylation of c-Jun in 293T cells. Loss of STRAP accelerates c-Jun turnover in fibroblasts and ectopic over-expression of STRAP in STRAP null fibroblasts increases c-Jun expression. Collectively, our findings indicate that STRAP regulates c-Jun stability by decreasing the ubiquitylation and proteosomal degradation of c-Jun.

  19. Selective Regulation of FGF19 and FGF21 Expression by Cellular and Nutritional Stress.

    Science.gov (United States)

    Shimizu, Makoto; Morimoto, Hitomi; Maruyama, Ryuto; Inoue, Jun; Sato, Ryuichiro

    2015-01-01

    Fibroblast growth factor 19 (FGF19) and FGF21 are members of a subfamily of the FGFs called endocrine FGFs. FGF19 regulates the bile acid synthetic pathway. FGF19 expression is induced by farnesoid X receptor (FXR), a nuclear hormone receptor activated by bile acids in the small intestine. FGF21 plays an important role in lipolysis that occurs in white adipose tissue. FGF21 expression is stimulated by the nuclear fatty acid receptor peroxisome proliferator-activated receptor α (PPARα) in the liver. FGF19 and FGF21 were recently identified as targets of activating transcription factor 4 (ATF4), which is activated in response to endoplasmic reticulum (ER) stress. ATF4 is also activated by oxidative stress and amino acid deprivation. In this study, we investigated FGF19 and FGF21 expression in response to oxidative stress and amino acid deprivation. We found that FGF19 mRNA is induced by oxidative stress inducers in Caco-2 cells, which are derived from the human intestinal epithelium, and rat intestinal epithelial IEC6 cells. In contrast, ileal FGF15 expression, the rodent ortholog of human FGF19, is not increased by oxidative stress. No notable changes in expression of FGF15/19 took place under amino acid deprivation either in vitro or in vivo. In contrast, FGF21 expression is induced by oxidative stress and amino acid deprivation both in vitro and in vivo. These results indicate distinctive patterns of regulation of FGF19 expression by ER stress, and FGF21 expression by ER stress, oxidative stress, and amino acid deprivation through ATF4 activation.

  20. Notes on a "printomere" mechanism of cellular memory and ion regulation of chromatin configurations.

    Science.gov (United States)

    Olovnikov, A M

    1999-12-01

    with chromatin proteins is able to pass over the replicative forks during printomere replication and replication of the chromosome. That is why any printomere can be stably retained on the chromosomal body in the course of numerous cell divisions. Owing to printomeres, cellular memory about the proper structure of chromatin decompactions is created, kept, and can be carried through the succession of doublings of differentiated cells.

  1. Hypusine: its post-translational formation in eukaryotic initiation factor 5A and its potential role in cellular regulation.

    Science.gov (United States)

    Park, M H; Wolff, E C; Folk, J E

    1993-05-01

    deoxyhypusine hydroxylase exhibit anti-proliferative effects by arresting mammalian cells at the G1/S boundary of the cell cycle. These results lay the foundation for the potential regulation of cellular events through the application of specific and potent inhibitors of hypusine biosynthesis.

  2. Pressuromodulation at the cell membrane as the basis for small molecule hormone and peptide regulation of cellular and nuclear function.

    Science.gov (United States)

    Sarin, Hemant

    2015-11-26

    Building on recent knowledge that the specificity of the biological interactions of small molecule hydrophiles and lipophiles across microvascular and epithelial barriers, and with cells, can be predicted on the basis of their conserved biophysical properties, and the knowledge that biological peptides are cell membrane impermeant, it has been further discussed herein that cellular, and thus, nuclear function, are primarily regulated by small molecule hormone and peptide/factor interactions at the cell membrane (CM) receptors. The means of regulating cellular, and thus, nuclear function, are the various forms of CM Pressuromodulation that exist, which include Direct CM Receptor-Mediated Stabilizing Pressuromodulation, sub-classified as Direct CM Receptor-Mediated Stabilizing Shift Pressuromodulation (Single, Dual or Tri) or Direct CM Receptor-Mediated Stabilizing Shift Pressuromodulation (Single, Dual or Tri) cum External Cationomodulation (≥3+ → 1+); which are with respect to acute CM receptor-stabilizing effects of small biomolecule hormones, growth factors or cytokines, and also include Indirect CM- or CM Receptor-Mediated Pressuromodulation, sub-classified as Indirect 1ary CM-Mediated Shift Pressuromodulation (Perturbomodulation), Indirect 2ary CM Receptor-Mediated Shift Pressuromodulation (Tri or Quad Receptor Internal Pseudo-Cationomodulation: SS 1+), Indirect 3ary CM Receptor-Mediated Shift Pressuromodulation (Single or Dual Receptor Endocytic External Cationomodulation: 2+) or Indirect (Pseudo) 3ary CM Receptor-Mediated Shift Pressuromodulation (Receptor Endocytic Hydroxylocarbonyloetheroylomodulation: 0), which are with respect to sub-acute CM receptor-stabilizing effects of small biomolecules, growth factors or cytokines. As a generalization, all forms of CM pressuromodulation decrease CM and nuclear membrane (NM) compliance (whole cell compliance), due to pressuromodulation of the intracellular microtubule network and increases the exocytosis of pre

  3. Curcumin inhibits cellular cholesterol accumulation by regulating SREBP-1/caveolin-1 signaling pathway in vascular smooth muscle cells

    Institute of Scientific and Technical Information of China (English)

    Hao-yu YUAN; Shuang-yu KUANG; Xing ZHENG; Hong-yan LING; Yun-bo YANG; Peng-ke YAN; Kai LI; Duan-fang LIAO

    2008-01-01

    Aim: To investigate the protective effect and the possible mechanism of curcumin on anti-atherosclerosis. Methods: Morphological changes of atherosclerotic le-sions taken from apoE knockout (apoE-/-) mice were determined by hematoxylin-eosin staining. Intracellular lipid droplets and lipid levels were assayed by oil red O staining and HPLC. The protein expression of caveolin-1 was quantified by West-ern blotting. Translocation and the expression of sterol response element-bind-ing protein-1 (SREBP-1) were indirectly detected by an immunofluorescence analysis. Results: The administration of 20 mg.kg-1.d-1 curcumin to apoE-/1 mice for 4 months induced a 50% reduction of atherosclerotic lesions and yielded a 5-fold increase in the caveolin-1 expression level as compared to the model group. Rat vascular smooth muscle cells (VSMC) pretreated with 50 mg.L-1 ox-lipid den-sity lipoprotein(ox-LDL) for 48 h increased cellular lipid contents, and stimulated SREBP-1 translocation, but decreased the caveolin-1 expression level. Lipid-loaded cells exposed to curcumin at various concentrations (12.5, 25, and 50 μmol.L-1) for different durations (0, 6, 12, 24, and 48 h) significantly diminished the number and area of cellular lipid droplets, total cholesterol, cholesterol ester, and free choles-terol accompanying the elevation of the caveolin-1 expression level (approximately 3-fold); the translocation of SREBP-1 from the cytoplasm to the nucleus was inhibited compared with the models. Lipid-loaded VSMC exposed to N-acetyl-Leu-Leu-norleucinal, a SREBP-1 protease inhibitor, showed increased nuclear trans-location of SREBP-1, reduced caveolin-1 expression level, and upregulated cellu-lar lipid levels. Conclusion: Curcumin inhibits ox-LDL-induced cholesterol accu-mulation in cultured VSMC through increasing the caveolin-1 expression via the inhibition of nuclear translocation of SREBP-1.

  4. Chitinase 3-like 1 Regulates Cellular and Tissue Responses via IL-13 Receptor α2

    Directory of Open Access Journals (Sweden)

    Chuan Hua He

    2013-08-01

    Full Text Available Members of the 18 glycosyl hydrolase (GH 18 gene family have been conserved over species and time and are dysregulated in inflammatory, infectious, remodeling, and neoplastic disorders. This is particularly striking for the prototypic chitinase-like protein chitinase 3-like 1 (Chi3l1, which plays a critical role in antipathogen responses where it augments bacterial killing while stimulating disease tolerance by controlling cell death, inflammation, and remodeling. However, receptors that mediate the effects of GH 18 moieties have not been defined. Here, we demonstrate that Chi3l1 binds to interleukin-13 receptor α2 (IL-13Rα2 and that Chi3l1, IL-13Rα2, and IL-13 are in a multimeric complex. We also demonstrate that Chi3l1 activates macrophage mitogen-activated protein kinase, protein kinase B/AKT, and Wnt/β-catenin signaling and regulates oxidant injury, apoptosis, pyroptosis, inflammasome activation, antibacterial responses, melanoma metastasis, and TGF-β1 production via IL-13Rα2-dependent mechanisms. Thus, IL-13Rα2 is a GH 18 receptor that plays a critical role in Chi3l1 effector responses.

  5. Regulation of cellular function via electromagnetic field frequency and extracellular environment: A theoretical- experimental approach

    Science.gov (United States)

    Taghian, Toloo; Sheikh, Abdul; Narmoneva, Daria; Kogan, Andrei

    2015-03-01

    Application of external electric field (EF) as a non-pharmacological, non-invasive tool to control cell function is of great therapeutic interest. We developed a theoretical-experimental approach to investigate the biophysical mechanisms of EF interaction with cells in electrode-free physiologically-relevant configuration. Our numerical results demonstrated that EF frequency is the major parameter to control cell response to EF. Non-oscillating or low-frequency EF leads to charge accumulation on the cell surface membrane that may mediate membrane initiated cell responses. In contrast, high-frequency EF penetrates the cell membrane and reaches cell cytoplasm, where it may directly activate intracellular responses. The theoretical predictions were confirmed in our experimental studies of the effects of applied EF on vascular cell function. Results show that non-oscillating EF increases vascular endothelial growth factor (VEGF) expression while field polarity controls cell adhesion rate. High-frequency, but not low frequency, EF provides differential regulation of cytoplasmic focal adhesion kinase and VEGF expression depending on the substrate, with increased expression in cells cultured on RGD-rich synthetic hydrogels, and decreased expression for matrigel culture. The authors acknowledge the financial support from the NSF (DMR-1206784 & DMR-0804199 to AK); the NIH (1R21 DK078814-01A1 to DN) and the University of Cincinnati (Interdisciplinary Faculty Research Support Grant to DN and AK).

  6. Positive and Negative Regulation of Cellular Immune Responses in Physiologic Conditions and Diseases

    Directory of Open Access Journals (Sweden)

    S. Viganò

    2012-01-01

    Full Text Available The immune system has evolved to allow robust responses against pathogens while avoiding autoimmunity. This is notably enabled by stimulatory and inhibitory signals which contribute to the regulation of immune responses. In the presence of a pathogen, a specific and effective immune response must be induced and this leads to antigen-specific T-cell proliferation, cytokines production, and induction of T-cell differentiation toward an effector phenotype. After clearance or control of the pathogen, the effector immune response must be terminated in order to avoid tissue damage and chronic inflammation and this process involves coinhibitory molecules. When the immune system fails to eliminate or control the pathogen, continuous stimulation of T cells prevents the full contraction and leads to the functional exhaustion of effector T cells. Several evidences both in vitro and in vivo suggest that this anergic state can be reverted by blocking the interactions between coinhibitory molecules and their ligands. The potential to revert exhausted or inactivated T-cell responses following selective blocking of their function made these markers interesting targets for therapeutic interventions in patients with persistent viral infections or cancer.

  7. BACE1 regulates the proliferation and cellular functions of Schwann cells.

    Science.gov (United States)

    Hu, Xiangyou; Hou, Hailong; Bastian, Chinthasagar; He, Wanxia; Qiu, Shupeng; Ge, Yingying; Yin, Xinhua; Kidd, Grahame J; Brunet, Sylvain; Trapp, Bruce D; Baltan, Selva; Yan, Riqiang

    2017-05-01

    BACE1 is an indispensable enzyme for generating β-amyloid peptides, which are excessively accumulated in brains of Alzheimer's patients. However, BACE1 is also required for proper myelination of peripheral nerves, as BACE1-null mice display hypomyelination. To determine the precise effects of BACE1 on myelination, here we have uncovered a role of BACE1 in the control of Schwann cell proliferation during development. We demonstrate that BACE1 regulates the cleavage of Jagged-1 and Delta-1, two membrane-bound ligands of Notch. BACE1 deficiency induces elevated Jag-Notch signaling activity, which in turn facilitates proliferation of Schwann cells. This increase in proliferation leads to shortened internodes and decreased Schmidt-Lanterman incisures. Functionally, evoked compound action potentials in BACE1-null nerves were significantly smaller and slower, with a clear decrease in excitability. BACE1-null nerves failed to effectively use lactate as an alternative energy source under conditions of increased physiological activity. Correlatively, BACE1-null mice showed reduced performance on rotarod tests. Collectively, our data suggest that BACE1 deficiency enhances proliferation of Schwann cell due to the elevated Jag1/Delta1-Notch signaling, but fails to myelinate axons efficiently due to impaired the neuregulin1-ErbB signaling, which has been documented.

  8. Technical Considerations in Emerging Medical Body Area Network Spectrum Regulation

    NARCIS (Netherlands)

    Wang, D.; Smith, D.; Ghosh, M.

    2011-01-01

    Medical Body Area Network (MBAN) technology provides a promising solution to improve patient care outcomes and lower healthcare costs. However, the current spectrum allocation cannot cater to increasing MBAN applications. Therefore, U.S., as well as other regions, have already been considering allo

  9. c-Myc and AMPK Control Cellular Energy Levels by Cooperatively Regulating Mitochondrial Structure and Function.

    Directory of Open Access Journals (Sweden)

    Lia R Edmunds

    Full Text Available The c-Myc (Myc oncoprotein and AMP-activated protein kinase (AMPK regulate glycolysis and oxidative phosphorylation (Oxphos although often for different purposes. Because Myc over-expression depletes ATP with the resultant activation of AMPK, we explored the potential co-dependency of and cross-talk between these proteins by comparing the consequences of acute Myc induction in ampk+/+ (WT and ampk-/- (KO murine embryo fibroblasts (MEFs. KO MEFs showed a higher basal rate of glycolysis than WT MEFs and an appropriate increase in response to activation of a Myc-estrogen receptor (MycER fusion protein. However, KO MEFs had a diminished ability to increase Oxphos, mitochondrial mass and reactive oxygen species in response to MycER activation. Other differences between WT and KO MEFs, either in the basal state or following MycER induction, included abnormalities in electron transport chain function, levels of TCA cycle-related oxidoreductases and cytoplasmic and mitochondrial redox states. Transcriptional profiling of pathways pertinent to glycolysis, Oxphos and mitochondrial structure and function also uncovered significant differences between WT and KO MEFs and their response to MycER activation. Finally, an unbiased mass-spectrometry (MS-based survey capable of quantifying ~40% of all mitochondrial proteins, showed about 15% of them to be AMPK- and/or Myc-dependent in their steady state. Significant differences in the activities of the rate-limiting enzymes pyruvate kinase and pyruvate dehydrogenase, which dictate pyruvate and acetyl coenzyme A abundance, were also differentially responsive to Myc and AMPK and could account for some of the differences in basal metabolite levels that were also detected by MS. Thus, Myc and AMPK are highly co-dependent and appear to engage in significant cross-talk across numerous pathways which support metabolic and ATP-generating functions.

  10. Copper Transporter 2 Regulates the Cellular Accumulation and Cytotoxicity of Cisplatin and Carboplatin

    Science.gov (United States)

    Blair, Brian G.; Larson, Christopher A.; Safaei, Roohangiz; Howell, Stephen B.

    2010-01-01

    Purpose Copper transporter 2 (CTR2) is known to mediate the uptake of Cu+1 by mammalian cells. Several other Cu transporters, including the influx transporter CTR1 and the two efflux transporters ATP7A and ATP7B, also regulate sensitivity to the platinum-containing drugs. We sought to determine the effect of CTR2 on influx, intracellular trafficking, and efflux of cisplatin and carboplatin. Experimental Design The role of CTR2 was examined by knocking down CTR2 expression in an isogenic pair of mouse embryo fibroblasts consisting of a CTR1+/+ line and a CTR1−/− line in which both CTR1 alleles had been deleted. CTR2 levels were determined by quantitative reverse transcription-PCR and Western blot analysis. Cisplatin (DDP) was quantified by inductively coupled plasma mass spectrometry and 64Cu and [14C]carboplatin (CBDCA) accumulation by γ and scintillation counting. Results Deletion of CTR1 reduced the uptake of Cu, DDP, and CBDCA and increased resistance to their cytotoxic effects by 2- to 3-fold. Knockdown of CTR2 increased uptake of Cu only in the CTR1+/+ cells. In contrast, knockdown of CTR2 increased whole-cell DDP uptake and DNA platination in both CTR1+/+ and CTR1−/− cells and proportionately enhanced cytotoxicity while producing no effect on vesicular accumulation or efflux. A significant correlation was found between CTR2 mRNA and protein levels and sensitivity to DDP in a panel of six ovarian carcinoma cell lines. Conclusions CTR2 is a major determinant of sensitivity to the cytotoxic effects of DDP and CBDCA. CTR2 functions by limiting drug accumulation, and its expression correlates with the sensitivity of human ovarian carcinoma cell lines to DDP. PMID:19509135

  11. Down-regulating causes of fibrosis with tamoxifen: a possible cellular/molecular approach to treat rhinophyma.

    Science.gov (United States)

    Payne, Wyatt G; Ko, Francis; Anspaugh, Stephanie; Wheeler, Chad K; Wright, Terry E; Robson, Martin C

    2006-03-01

    Fibrosis and proliferative scarring are prominent features of the severe forms of rhinophyma. Up-regulation of growth and fibroblast kinetics are hallmarks of fibrosis. Persistent overexpression or dysregulated activation of the fibrogenic isoforms of transforming growth factor beta (TGF-beta) is associated with the increased fibroblast function leading to fibrotic conditions such as rhinophyma. Tamoxifen, a synthetic nonsteroidal antiestrogen, can neutralize or down-regulate TGF-beta. Fibroblast-populated collagen lattices (FPCLs) were constructed from fibroblasts cultured from rhinophyma or normal nasal skin. One-half of each set of FPCLs was treated with Tamoxifen. Lattice contraction was serially measured over 5 days, and the supernatants of the cultures were analyzed for TGF-beta-2 by immunoassay. Tamoxifen significantly decreased fibroblast activity by decreasing contraction of the treated lattices (P < 0.05) and significantly decreased the production/secretion of TGF-beta-2 by rhinophyma fibroblasts (P < 0.001). These results suggest a possible new cellular/molecular approach to the treatment of the fibrotic varieties of rhinophyma.

  12. Enrichment from birth accelerates the functional and cellular development of a motor control area in the mouse.

    Directory of Open Access Journals (Sweden)

    Teresa Simonetti

    Full Text Available BACKGROUND: There is strong evidence that sensory experience in early life has a profound influence on the development of sensory circuits. Very little is known, however, about the role of experience in the early development of striatal networks which regulate both motor and cognitive function. To address this, we have investigated the influence of early environmental enrichment on motor development. METHODOLOGY/PRINCIPAL FINDINGS: Mice were raised in standard or enriched housing from birth. For animals assessed as adults, half of the mice had their rearing condition reversed at weaning to enable the examination of the effects of pre- versus post-weaning enrichment. We found that exclusively pre-weaning enrichment significantly improved performance on the Morris water maze compared to non-enriched mice. The effects of early enrichment on the emergence of motor programs were assessed by performing behavioural tests at postnatal day 10. Enriched mice traversed a significantly larger region of the test arena in an open-field test and had improved swimming ability compared to non-enriched cohorts. A potential cellular correlate of these changes was investigated using Wisteria-floribunda agglutinin (WFA staining to mark chondroitin-sulfate proteoglycans (CSPGs. We found that the previously reported transition of CSPG staining from striosome-associated clouds to matrix-associated perineuronal nets (PNNs is accelerated in enriched mice. CONCLUSIONS/SIGNIFICANCE: This is the first demonstration that the early emergence of exploratory as well as coordinated movement is sensitive to experience. These behavioural changes are correlated with an acceleration of the emergence of striatal PNNs suggesting that they may consolidate the neural circuits underlying these behaviours. Finally, we confirm that pre-weaning experience can lead to life long changes in the learning ability of mice.

  13. Regulation of cellular behaviors of fibroblasts related to wound healing by sol-gel derived bioactive glass particles.

    Science.gov (United States)

    Xie, Weihan; Chen, Xiaofeng; Miao, Guohou; Tang, Jieying; Fu, Xiaoling

    2016-10-01

    Sol-gel derived bioactive glass (BG) holds great potential in the application of skin repair. However, the specific regulation of BG on skin cells is still unclear and demands more investigation. Herein, we synthesized sol-gel derived BGs with different compositions (60S, 70S, 80S, and 90S) and found 90S BGs (90 mol % SiO2 , 6 mol % CaO, 4 mol % P2 O5 ) exhibited the best supportiveness for the proliferation of normal human foreskin fibroblasts. Thus, 90S BG particles were used as a model to systematically study the wound healing related cellular response of fibroblasts to BGs. Time-lapse imaging revealed a promoted fibroblast motility stimulated by 90S BG particles. Results on the expression of extracellular matrix (ECM) related genes illustrated that 90S BG particles modulated the synthesis capacity for critical ECM molecules including type I collagen, type III collagen, fibronectin, and tenascin-C. Moreover, the myofibroblastic differentiation of fibroblasts was greatly inhibited by 90S BG particles. Further analysis on the intracellular signaling pathways demonstrated that 90S BG particles down-regulated the collagen synthesis and fibroblast-to-myofibroblast differentiation via TGF-β1-Smad2 signaling, evidenced by the decreased expression levels of TGF-β receptor I and its downstream effector Smad2. Our study provided a further understanding of the specific regulation of 90S BG particles on fibroblasts, which may guide the future design of BG based wound dressing and benefit the clinical application of BG particles in skin repair. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 2420-2429, 2016.

  14. Mechanistic studies for the role of cellular nucleic-acid-binding protein (CNBP) in regulation of c-myc transcription.

    Science.gov (United States)

    Chen, Siqi; Su, Lijuan; Qiu, Jun; Xiao, Nannan; Lin, Jing; Tan, Jia-Heng; Ou, Tian-Miao; Gu, Lian-Quan; Huang, Zhi-Shu; Li, Ding

    2013-10-01

    Guanine-rich sequence of c-myc nuclease hypersensitive element (NHE) III1 is known to fold in G-quadruplex and subsequently serves as a transcriptional silencer. Cellular nucleic-acid-binding protein (CNBP), a highly conserved zinc-finger protein with multiple biological functions, could bind to c-myc NHE III1 region, specifically to the single strand G-rich sequence. In the present study, a variety of methods, including cloning, expression and purification of protein, EMSA, CD, FRET, Ch-IP, RNA interference, luciferase reporter assay, SPR, co-immunoprecipitation, and co-transfection, were applied to investigate the mechanism for the role of CNBP in regulating c-myc transcription. We found that human CNBP specifically bound to the G-rich sequence of c-myc NHE III1 region both in vitro and in cellulo, and subsequently promoted the formation of G-quadruplex. CNBP could induce a transient decrease followed by an increase in c-myc transcription in vivo. The interaction of CNBP with NM23-H2 was responsible for the increase of c-myc transcription. Based on above experimental results, a new mechanism, involving G-quadruplex related CNBP/NM23-H2 interaction, for the regulation of c-myc transcription was proposed. These findings indicated that the regulation of c-myc transcription through NHE III1 region might be governed by mechanisms involving complex protein-protein interactions, and suggested a new possibility of CNBP as a potential anti-cancer target based on CNBP's biological function in c-myc transcription. Copyright © 2013 Elsevier B.V. All rights reserved.

  15. Regulation of HTLV-1 tax stability, cellular trafficking and NF-κB activation by the ubiquitin-proteasome pathway.

    Science.gov (United States)

    Lavorgna, Alfonso; Harhaj, Edward William

    2014-10-23

    Human T-cell leukemia virus type 1 (HTLV-1) is a complex retrovirus that infects CD4+ T cells and causes adult T-cell leukemia/lymphoma (ATLL) in 3%-5% of infected individuals after a long latent period. HTLV-1 Tax is a trans-activating protein that regulates viral gene expression and also modulates cellular signaling pathways to enhance T-cell proliferation and cell survival. The Tax oncoprotein promotes T-cell transformation, in part via constitutive activation of the NF-κB transcription factor; however, the underlying mechanisms remain unknown. Ubiquitination is a type of post-translational modification that occurs in a three-step enzymatic cascade mediated by E1, E2 and E3 enzymes and regulates protein stability as well as signal transduction, protein trafficking and the DNA damage response. Emerging studies indicate that Tax hijacks the ubiquitin machinery to activate ubiquitin-dependent kinases and downstream NF-κB signaling. Tax interacts with the E2 conjugating enzyme Ubc13 and is conjugated on C-terminal lysine residues with lysine 63-linked polyubiquitin chains. Tax K63-linked polyubiquitination may serve as a platform for signaling complexes since this modification is critical for interactions with NEMO and IKK. In addition to NF-κB signaling, mono- and polyubiquitination of Tax also regulate its subcellular trafficking and stability. Here, we review recent advances in the diverse roles of ubiquitin in Tax function and how Tax usurps the ubiquitin-proteasome pathway to promote oncogenesis.

  16. Involvement of the iron regulatory protein from Eisenia andrei earthworms in the regulation of cellular iron homeostasis.

    Directory of Open Access Journals (Sweden)

    Petra Procházková

    Full Text Available Iron homeostasis in cells is regulated by iron regulatory proteins (IRPs that exist in different organisms. IRPs are cytosolic proteins that bind to iron-responsive elements (IREs of the 5'- or 3'-untranslated regions (UTR of mRNAs that encode many proteins involved in iron metabolism. In this study, we have cloned and described a new regulatory protein belonging to the family of IRPs from the earthworm Eisenia andrei (EaIRP. The earthworm IRE site in 5'-UTR of ferritin mRNA most likely folds into a secondary structure that differs from the conventional IRE structures of ferritin due to the absence of a typically unpaired cytosine that participates in protein binding. Prepared recombinant EaIRP and proteins from mammalian liver extracts are able to bind both mammalian and Eisenia IRE structures of ferritin mRNA, although the affinity of the rEaIRP/Eisenia IRE structure is rather low. This result suggests the possible contribution of a conventional IRE structure. When IRP is supplemented with a Fe-S cluster, it can function as a cytosolic aconitase. Cellular cytosolic and mitochondrial fractions, as well as recombinant EaIRP, exhibit aconitase activity that can be abolished by the action of oxygen radicals. The highest expression of EaIRP was detected in parts of the digestive tract. We can assume that earthworms may possess an IRE/IRP regulatory network as a potential mechanism for maintaining cellular iron homeostasis, although the aconitase function of EaIRP is most likely more relevant.

  17. hnRNP A1 antagonizes cellular senescence and senescence-associated secretory phenotype via regulation of SIRT1 mRNA stability.

    Science.gov (United States)

    Wang, Hui; Han, Limin; Zhao, Ganye; Shen, Hong; Wang, Pengfeng; Sun, Zhaomeng; Xu, Chenzhong; Su, Yuanyuan; Li, Guodong; Tong, Tanjun; Chen, Jun

    2016-09-09

    Senescent cells display a senescence-associated secretory phenotype (SASP) which contributes to tumor suppression, aging, and cancer. However, the underlying mechanisms for SASP regulation are not fully elucidated. SIRT1, a nicotinamide adenosine dinucleotide-dependent deacetylase, plays multiple roles in metabolism, inflammatory response, and longevity, etc. However, its posttranscriptional regulation and its roles in cellular senescence and SASP regulation are still elusive. Here, we identify the RNA-binding protein hnRNP A1 as a posttranscriptional regulator of SIRT1, as well as cell senescence and SASP regulator. hnRNP A1 directly interacts with the 3' untranslated region of SIRT1 mRNA, promotes its stability, and increases SIRT1 expression. hnRNP A1 delays replicative cellular senescence and prevents from Ras OIS via upregulation of SIRT1 expression to deacetylate NF-κB, thus blunting its transcriptional activity and subsequent IL-6/IL-8 induction. hnRNP A1 overexpression promotes cell transformation and tumorigenesis in a SIRT1-dependent manner. Together, our findings unveil a novel posttranscriptional regulation of SIRT1 by hnRNP A1 and uncover a critical role of hnRNP A1-SIRT1-NF-κB pathway in regulating cellular senescence and SASP expression. © 2016 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.

  18. 7 CFR 301.86-4 - Conditions governing the interstate movement of regulated articles from quarantined areas.

    Science.gov (United States)

    2010-01-01

    ... or unloaded in the quarantined area; and (D) The article has not been combined or commingled with... regulated articles from quarantined areas. 301.86-4 Section 301.86-4 Agriculture Regulations of the... regulated articles from quarantined areas. (a) Any regulated article may be moved interstate from...

  19. Cellular mechanisms regulating neuronal excitability: Functional implications and in epilepsy | Mecanismos celulares reguladores de la excitabilidad celular: Implicaciones funcionales y en epilepsia

    OpenAIRE

    Cabezas-Fernández, C.; Martín-Montiel, E. D.; Buño, W

    2003-01-01

    Introduction and method. The cellular mechanisms that regulate neuronal excitability and the propagation of electrical signals in the dendrites of pyramidal neurons are incompletely understood and of key functional and pathological importance. The capacity of dendrites to actively propagate action potentials is vital in processes related to memory and learning. The deregulation of dendritic excitability may also contribute to epilepsy. The contributions of ionic conductances that regulate neu...

  20. Cellular and molecular regulation of the activation of mammalian primordial follicles: somatic cells initiate follicle activation in adulthood.

    Science.gov (United States)

    Zhang, Hua; Liu, Kui

    2015-01-01

    The first small follicles to appear in the mammalian ovaries are primordial follicles. The initial pool of primordial follicles serves as the source of developing follicles and oocytes for the entire reproductive lifespan of the animal. Although the selective activation of primordial follicles is critical for female fertility, its underlying mechanisms have remained poorly understood. A search of PubMed was conducted to identify peer-reviewed literature pertinent to the study of mammalian primordial follicle activation, especially recent reports of the role of primordial follicle granulosa cells (pfGCs) in regulating this process. In recent years, molecular mechanisms that regulate the activation of primordial follicles have been elucidated, mostly through the use of genetically modified mouse models. Several molecules and pathways operating in both the somatic pfGCs and oocytes, such as the phosphatidylinositol 3 kinase (PI3K) and the mechanistic target of rapamycin complex 1 (mTORC1) pathways, have been shown to be important for primordial follicle activation. More importantly, recent studies have provided an updated view of how exactly signaling pathways in pfGCs and in oocytes, such as the KIT ligand (KL) and KIT, coordinate in adult ovaries so that the activation of primordial follicles is achieved. In this review, we have provided an updated picture of how mammalian primordial follicles are activated. The functional roles of pfGCs in governing the activation of primordial follicles in adulthood are highlighted. The in-depth understanding of the cellular and molecular mechanisms of primordial follicle activation will hopefully lead to more treatments of female infertility, and the current progress indicates that the use of existing primordial follicles as a source for obtaining fertilizable oocytes as a new treatment for female infertility is just around the corner. © The Author 2015. Published by Oxford University Press on behalf of the European Society of

  1. Dioscorea alata attenuates renal interstitial cellular fibrosis by regulating Smad- and epithelial-mesenchymal transition signaling pathways.

    Directory of Open Access Journals (Sweden)

    Shu-Fen Liu

    Full Text Available Renal interstitial fibrosis is characterized by increased extracellular matrix (ECM synthesis. Epithelial-mesenchymal transition (EMT in kidneys is driven by regulated expression of fibrogenic cytokines such as transforming growth factor-beta (TGF-β. Yam, or Dioscorea alata (DA is an important herb in Chinese medicine widely used for the treatment of clinical diabetes mellitus. However, the fibrosis regulatory effect of DA is unclear. Thus, we examined TGF-β signaling mechanisms against EMT in rat fibroblast cells (NRK-49F. The characterization of DA water-extracts used various methods; after inducing cellular fibrosis in NRK-49F cells by treatment with β-hydroxybutyrate (β-HB (10 mM, we used Western blotting to examine the protein expression in the TGF-β-related signal protein type I and type II TGF-β receptors, Smads2 and Smad3 (Smad2/3, pSmad2 and Smad3 (pSmad2/3, Smads4, Smads7, and EMT markers. These markers included E-cadherin, alpha-smooth muscle actin (α-SMA, and matrix metalloproteinase-2 (MMP-2. Bioactive TGF-β and fibronectin levels in the culture media were determined using ELISA. Expressions of fibronectin and Snail transcription factor, an EMT-regulatory transcription factor, were assessed by immunofluorescence staining. DA extract dose-dependently (50-200 µg/mL suppressed β-HB-induced expression of fibronectin in NRK-49F cells concomitantly with the inhibition of Smad2/3, pSmad2/3, and Smad4. By contrast, Smad7 expression was significantly increased. DA extract caused a decrease in α-SMA (α-smooth muscle actin and MMP-2 levels, and an increase in E-cadherin expression. We propose that DA extract might act as a novel fibrosis antagonist, which acts partly by down regulating the TGF-β/smad signaling pathway and modulating EMT expression.

  2. BRD4 Phosphorylation Regulates HPV E2-Mediated Viral Transcription, Origin Replication, and Cellular MMP-9 Expression

    Directory of Open Access Journals (Sweden)

    Shwu-Yuan Wu

    2016-08-01

    Full Text Available Post-translational modification can modulate protein conformation and alter binding partner recruitment within gene regulatory regions. Here, we report that bromodomain-containing protein 4 (BRD4, a transcription co-factor and chromatin regulator, uses a phosphorylation-induced switch mechanism to recruit E2 protein encoded by cancer-associated human papillomavirus (HPV to viral early gene and cellular matrix metalloproteinase-9 (MMP-9 promoters. Enhanced MMP-9 expression, induced upon keratinocyte differentiation, occurs via BRD4-dependent recruitment of active AP-1 and NF-κB to their target sequences. This is triggered by replacement of AP-1 family members JunB and JunD by c-Jun and by re-localization of NF-κB from the cytoplasm to the nucleus. In addition, BRD4 phosphorylation is critical for E2- and origin-dependent HPV DNA replication. A class of phospho-BRD4-targeting compounds, distinct from the BET bromodomain inhibitors, effectively blocks BRD4 phosphorylation-specific functions in transcription and factor recruitment.

  3. Shroom3 functions downstream of planar cell polarity to regulate myosin II distribution and cellular organization during neural tube closure

    Directory of Open Access Journals (Sweden)

    Erica M. McGreevy

    2015-01-01

    Full Text Available Neural tube closure is a critical developmental event that relies on actomyosin contractility to facilitate specific processes such as apical constriction, tissue bending, and directional cell rearrangements. These complicated processes require the coordinated activities of Rho-Kinase (Rock, to regulate cytoskeletal dynamics and actomyosin contractility, and the Planar Cell Polarity (PCP pathway, to direct the polarized cellular behaviors that drive convergent extension (CE movements. Here we investigate the role of Shroom3 as a direct linker between PCP and actomyosin contractility during mouse neural tube morphogenesis. In embryos, simultaneous depletion of Shroom3 and the PCP components Vangl2 or Wnt5a results in an increased liability to NTDs and CE failure. We further show that these pathways intersect at Dishevelled, as Shroom3 and Dishevelled 2 co-distribute and form a physical complex in cells. We observed that multiple components of the Shroom3 pathway are planar polarized along mediolateral cell junctions in the neural plate of E8.5 embryos in a Shroom3 and PCP-dependent manner. Finally, we demonstrate that Shroom3 mutant embryos exhibit defects in planar cell arrangement during neural tube closure, suggesting a role for Shroom3 activity in CE. These findings support a model in which the Shroom3 and PCP pathways interact to control CE and polarized bending of the neural plate and provide a clear illustration of the complex genetic basis of NTDs.

  4. Shroom3 functions downstream of planar cell polarity to regulate myosin II distribution and cellular organization during neural tube closure.

    Science.gov (United States)

    McGreevy, Erica M; Vijayraghavan, Deepthi; Davidson, Lance A; Hildebrand, Jeffrey D

    2015-01-16

    Neural tube closure is a critical developmental event that relies on actomyosin contractility to facilitate specific processes such as apical constriction, tissue bending, and directional cell rearrangements. These complicated processes require the coordinated activities of Rho-Kinase (Rock), to regulate cytoskeletal dynamics and actomyosin contractility, and the Planar Cell Polarity (PCP) pathway, to direct the polarized cellular behaviors that drive convergent extension (CE) movements. Here we investigate the role of Shroom3 as a direct linker between PCP and actomyosin contractility during mouse neural tube morphogenesis. In embryos, simultaneous depletion of Shroom3 and the PCP components Vangl2 or Wnt5a results in an increased liability to NTDs and CE failure. We further show that these pathways intersect at Dishevelled, as Shroom3 and Dishevelled 2 co-distribute and form a physical complex in cells. We observed that multiple components of the Shroom3 pathway are planar polarized along mediolateral cell junctions in the neural plate of E8.5 embryos in a Shroom3 and PCP-dependent manner. Finally, we demonstrate that Shroom3 mutant embryos exhibit defects in planar cell arrangement during neural tube closure, suggesting a role for Shroom3 activity in CE. These findings support a model in which the Shroom3 and PCP pathways interact to control CE and polarized bending of the neural plate and provide a clear illustration of the complex genetic basis of NTDs.

  5. C/EBPγ Is a Critical Regulator of Cellular Stress Response Networks through Heterodimerization with ATF4.

    Science.gov (United States)

    Huggins, Christopher J; Mayekar, Manasi K; Martin, Nancy; Saylor, Karen L; Gonit, Mesfin; Jailwala, Parthav; Kasoji, Manjula; Haines, Diana C; Quiñones, Octavio A; Johnson, Peter F

    2015-12-14

    The integrated stress response (ISR) controls cellular adaptations to nutrient deprivation, redox imbalances, and endoplasmic reticulum (ER) stress. ISR genes are upregulated in stressed cells, primarily by the bZIP transcription factor ATF4 through its recruitment to cis-regulatory C/EBP:ATF response elements (CAREs) together with a dimeric partner of uncertain identity. Here, we show that C/EBPγ:ATF4 heterodimers, but not C/EBPβ:ATF4 dimers, are the predominant CARE-binding species in stressed cells. C/EBPγ and ATF4 associate with genomic CAREs in a mutually dependent manner and coregulate many ISR genes. In contrast, the C/EBP family members C/EBPβ and C/EBP homologous protein (CHOP) were largely dispensable for induction of stress genes. Cebpg(-/-) mouse embryonic fibroblasts (MEFs) proliferate poorly and exhibit oxidative stress due to reduced glutathione levels and impaired expression of several glutathione biosynthesis pathway genes. Cebpg(-/-) mice (C57BL/6 background) display reduced body size and microphthalmia, similar to ATF4-null animals. In addition, C/EBPγ-deficient newborns die from atelectasis and respiratory failure, which can be mitigated by in utero exposure to the antioxidant, N-acetyl-cysteine. Cebpg(-/-) mice on a mixed strain background showed improved viability but, upon aging, developed significantly fewer malignant solid tumors than WT animals. Our findings identify C/EBPγ as a novel antioxidant regulator and an obligatory ATF4 partner that controls redox homeostasis in normal and cancerous cells.

  6. A Stochastic Model of the Yeast Cell Cycle Reveals Roles for Feedback Regulation in Limiting Cellular Variability.

    Science.gov (United States)

    Barik, Debashis; Ball, David A; Peccoud, Jean; Tyson, John J

    2016-12-01

    The cell division cycle of eukaryotes is governed by a complex network of cyclin-dependent protein kinases (CDKs) and auxiliary proteins that govern CDK activities. The control system must function reliably in the context of molecular noise that is inevitable in tiny yeast cells, because mistakes in sequencing cell cycle events are detrimental or fatal to the cell or its progeny. To assess the effects of noise on cell cycle progression requires not only extensive, quantitative, experimental measurements of cellular heterogeneity but also comprehensive, accurate, mathematical models of stochastic fluctuations in the CDK control system. In this paper we provide a stochastic model of the budding yeast cell cycle that accurately accounts for the variable phenotypes of wild-type cells and more than 20 mutant yeast strains simulated in different growth conditions. We specifically tested the role of feedback regulations mediated by G1- and SG2M-phase cyclins to minimize the noise in cell cycle progression. Details of the model are informed and tested by quantitative measurements (by fluorescence in situ hybridization) of the joint distributions of mRNA populations in yeast cells. We use the model to predict the phenotypes of ~30 mutant yeast strains that have not yet been characterized experimentally.

  7. The cellular prion protein negatively regulates phagocytosis and cytokine expression in murine bone marrow-derived macrophages.

    Directory of Open Access Journals (Sweden)

    Min Wang

    Full Text Available The cellular prion protein (PrP(C is a glycosylphosphatidylinositol (GPI-anchored glycoprotein on the cell surface. Previous studies have demonstrated contradictory roles for PrP(C in connection with the phagocytic ability of macrophages. In the present work, we investigated the function of PrP(C in phagocytosis and cytokine expression in bone marrow-derived macrophages infected with Escherichia coli. E. coli infection induced an increase in the PRNP mRNA level. Knockout of PrP(C promoted bacterial uptake; upregulated Rab5, Rab7, and Eea1 mRNA expression; and increased the recruitment of lysosomal-associated membrane protein-2 to phagosomes, suggesting enhanced microbicidal activity. Remarkably, knockout of PrP(C suppressed the proliferation of internalized bacteria and increased the expression of cytokines such as interleukin-1β. Collectively, our data reveal an important role of PrP(C as a negative regulator for phagocytosis, phagosome maturation, cytokine expression, and macrophage microbicidal activity.

  8. Cellular senescence regulated by SWI/SNF complex subunits through p53/p21 and p16/pRB pathway.

    Science.gov (United States)

    He, Ling; Chen, Ying; Feng, Jianguo; Sun, Weichao; Li, Shun; Ou, Mengting; Tang, Liling

    2017-09-01

    SWI/SNF complex is an evolutionarily well-conserved chromatin-remodeling complex, which is implicated in the nucleosomes removing or sliding, impacting on the DNA repair, replication and genes expression regulation. The SWI/SNF complex consists up to 12 protein subunits. The catalytic subunits are BRG1 or BRM, which are exclusive ATPase subunits. BRG1 has been reported to play an important role in cellular senescence. However, The function of non-catalytic subunits involved in cellular senescence is rarely investigated. Therefore, we focused on the senescence regulation roles of SWI/SNF non-catalytic subunits in cellular senescent model induced by H2O2. H2O2 treatment was used to induce cellular senescence models in vitro. Screening the candidate subunits involved in this process by comparing the expression levels of SWI/SNF subunits with/without H2O2 treatment. Over-expression and knockdown the candidate subunits were utilized to investigate the functions and mechanism of the subunits involved in senescence regulation. The expressions of BAF57, BAF60a and SNF5 were changed significantly after H2O2 treatment. Overexpression of the three subunits separately induced cell growth arrest in both HaCaT and GLL19 cells, while knockdown of the subunits separately eased the senescence induced by H2O2 treatment. Results further showed that BAF57, BAF60a and SNF5 regulated cellular senescence via both p53/p21 and p16/pRB pathways, and the three subunits all had a directly interaction with p53. These results indicated that BAF57, BAF60a and SNF5 might act as novel pro-senescence factors in both normal and tumor human skin cells. Therefore, inhibiting expression of the three factors might delay the cellular senescence process. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. 75 FR 51374 - Regulated Navigation Areas, Safety Zones, Security Zones; Deepwater Ports in Boston Captain of...

    Science.gov (United States)

    2010-08-20

    ... infrastructure within 1,000 meters of Neptune's STL buoys, and will prohibit vessels from commercial fishing or... regulation to safeguard vessels, harbors, ports, or waterfront facilities from destruction, loss, or injury.... The purpose of these regulated areas is to protect vessels and mariners from the potential...

  10. 33 CFR 165.806 - Sabine Neches Waterway, Texas-regulated navigation area.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Sabine Neches Waterway, Texas... § 165.806 Sabine Neches Waterway, Texas—regulated navigation area. (a) The following is a regulated navigation area—The Sabine Neches Waterway which includes the following waters: Sabine Pass Channel,...

  11. Superoxide Dismutase 1 Regulation of CXCR4-Mediated Signaling in Prostate Cancer Cells is Dependent on Cellular Oxidative State

    Directory of Open Access Journals (Sweden)

    Brent Young

    2015-11-01

    Full Text Available Background/Aims: CXCL12, acting via one of its G protein-coupled receptors, CXCR4, is a chemoattractant for a broad range of cell types, including several types of cancer cells. Elevated expression of CXCR4, and its ligand CXCL12, play important roles in promoting cancer metastasis. Cancer cells have the potential for rapid and unlimited growth in an area that may have restricted blood supply, as oxidative stress is a common feature of solid tumors. Recent studies have reported that enhanced expression of cytosolic superoxide dismutase (SOD1, a critical enzyme responsible for regulation of superoxide radicals, may increase the aggressive and invasive potential of malignant cells in some cancers. Methods: We used a variety of biochemical approaches and a prostate cancer cell line to study the effects of SOD1 on CXCR4 signaling. Results: Here, we report a direct interaction between SOD1 and CXCR4. We showed that SOD1 interacts directly with the first intracellular loop (ICL1 of CXCR4 and that the CXCL12/CXCR4-mediated regulation of AKT activation, apoptosis and cell migration in prostate cancer (PCa cells is differentially modulated under normal versus hypoxic conditions when SOD1 is present. Conclusions: This study highlights a potential new regulatory mechanism by which a sensor of the oxidative environment could directly regulate signal transduction of a receptor involved in cancer cell survival and migration.

  12. Mitf is a master regulator of the v-ATPase, forming a control module for cellular homeostasis with v-ATPase and TORC1

    Science.gov (United States)

    Zhang, Tianyi; Zhou, Qingxiang; Ogmundsdottir, Margret Helga; Möller, Katrin; Siddaway, Robert; Larue, Lionel; Hsing, Michael; Kong, Sek Won; Goding, Colin Ronald; Palsson, Arnar; Steingrimsson, Eirikur; Pignoni, Francesca

    2015-01-01

    ABSTRACT The v-ATPase is a fundamental eukaryotic enzyme that is central to cellular homeostasis. Although its impact on key metabolic regulators such as TORC1 is well documented, our knowledge of mechanisms that regulate v-ATPase activity is limited. Here, we report that the Drosophila transcription factor Mitf is a master regulator of this holoenzyme. Mitf directly controls transcription of all 15 v-ATPase components through M-box cis-sites and this coordinated regulation affects holoenzyme activity in vivo. In addition, through the v-ATPase, Mitf promotes the activity of TORC1, which in turn negatively regulates Mitf. We provide evidence that Mitf, v-ATPase and TORC1 form a negative regulatory loop that maintains each of these important metabolic regulators in relative balance. Interestingly, direct regulation of v-ATPase genes by human MITF also occurs in cells of the melanocytic lineage, showing mechanistic conservation in the regulation of the v-ATPase by MITF family proteins in fly and mammals. Collectively, this evidence points to an ancient module comprising Mitf, v-ATPase and TORC1 that serves as a dynamic modulator of metabolism for cellular homeostasis. PMID:26092939

  13. MEASUREMENT OF APPLICATION OF ISO 27001 OF CUSTOMER CELLULAR CARD CONFIDENTIALITY DATA IN PT. XYZ AREA JAKARTA

    Directory of Open Access Journals (Sweden)

    Krishna Rahadian

    2014-10-01

    Full Text Available The purpose of this study was to evaluate the effects of the process of ISO 27001 with respect to the confidentiality of customer cellular card Jakarta and to improve cellular card customer data confidentiality at PT.XYZ from data leakage of the customer data due to the third party involvement, clean-desk policy, and access right. Recommendation regarding the improvement is provided after reviewing the confidentiality of customer data. The survey in this study is conducted by questionnaire. From the evaluation results of the questionnaire, it is concluded that the larger customer data leaks are mainly caused by the external factors.

  14. Regulation of cellular adhesion molecule expression in murine oocytes,peri-implantation and post-implantation embryos

    Institute of Scientific and Technical Information of China (English)

    DAVID; P; LU; LINA; TIAN; CHRIS; O'; NEILL; NICHOLAS; JC; KING

    2002-01-01

    Expression of the adhesion molecules, ICAM-1, VCAM-1, NCAM, CD44, CD49d (VLA-4, α chain),and CD11a (LFA-1, α chain) on mouse oocytes, and pre- and peri-implantation stage embryos was exam-ined by quantitative indirect immunofluorescence microscopy. ICAM-1 was most strongly expressed at theoocyte stage, gradually declining almost to undetectable levels by the expanded blastocyst stage. NCAM,also expressed maximally on the oocyte, declined to undetectable levels beyond the morula stage. On theother hand, CD44 declined from highest expression at the oocyte stage to show a second maximum at thecompacted 8-cell/morula. This molecule exhibited high expression around contact areas between trophecto-derm and zona pellucida during blastocyst hatching. CD49d was highly expressed in the oocyte, remainedsignificantly expressed throughout and after blastocyst hatching was expressed on the polar trophecto-derm. Like CD44, CD49d declined to undetectable levels at the blastocyst outgrowth stage. Expression ofboth VCAM-1 and CD11a was undetectable throughout. The diametrical temporal expression pattern ofICAM-1 and NCAM compared to CD44 and CD49d suggest that dynamic changes in expression of adhesionmolecules may be important for interaction of the embryo with the maternal cellular environment as wellas for continuing development and survival of the early embryo.

  15. COX19 mediates the transduction of a mitochondrial redox signal from SCO1 that regulates ATP7A-mediated cellular copper efflux

    OpenAIRE

    Leary, Scot C; Cobine, Paul A.; Nishimura, Tamiko; Verdijk, Robert M; de Krijger, Ronald; Coo, René; Tarnopolsky, Mark A.; Winge, Dennis R; Eric A Shoubridge

    2013-01-01

    SCO1 and SCO2 are metallochaperones whose principal function is to add two copper ions to the catalytic core of cytochrome c oxidase (COX). However, affected tissues of SCO1 and SCO2 patients exhibit a combined deficiency in COX activity and total copper content, suggesting additional roles for these proteins in the regulation of cellular copper homeostasis. Here we show that both the redox state of the copper-binding cysteines of SCO1 and the abundance of SCO2 correlate with cellular copper ...

  16. 75 FR 27638 - Regulated Navigation Area; U.S. Navy Submarines, Hood Canal, WA

    Science.gov (United States)

    2010-05-18

    ... No. USCG-2009-1058] RIN 1625-AA11 Regulated Navigation Area; U.S. Navy Submarines, Hood Canal, WA... whenever any U.S. Navy submarine is operating in that area and is being escorted by the Coast Guard. The RNA is necessary to help ensure the safety and security of the submarines, their Coast Guard...

  17. C/EBPγ Is a Critical Regulator of Cellular Stress Response Networks through Heterodimerization with ATF4

    Science.gov (United States)

    Huggins, Christopher J.; Mayekar, Manasi K.; Martin, Nancy; Saylor, Karen L.; Gonit, Mesfin; Jailwala, Parthav; Kasoji, Manjula; Haines, Diana C.; Quiñones, Octavio A.

    2015-01-01

    The integrated stress response (ISR) controls cellular adaptations to nutrient deprivation, redox imbalances, and endoplasmic reticulum (ER) stress. ISR genes are upregulated in stressed cells, primarily by the bZIP transcription factor ATF4 through its recruitment to cis-regulatory C/EBP:ATF response elements (CAREs) together with a dimeric partner of uncertain identity. Here, we show that C/EBPγ:ATF4 heterodimers, but not C/EBPβ:ATF4 dimers, are the predominant CARE-binding species in stressed cells. C/EBPγ and ATF4 associate with genomic CAREs in a mutually dependent manner and coregulate many ISR genes. In contrast, the C/EBP family members C/EBPβ and C/EBP homologous protein (CHOP) were largely dispensable for induction of stress genes. Cebpg−/− mouse embryonic fibroblasts (MEFs) proliferate poorly and exhibit oxidative stress due to reduced glutathione levels and impaired expression of several glutathione biosynthesis pathway genes. Cebpg−/− mice (C57BL/6 background) display reduced body size and microphthalmia, similar to ATF4-null animals. In addition, C/EBPγ-deficient newborns die from atelectasis and respiratory failure, which can be mitigated by in utero exposure to the antioxidant, N-acetyl-cysteine. Cebpg−/− mice on a mixed strain background showed improved viability but, upon aging, developed significantly fewer malignant solid tumors than WT animals. Our findings identify C/EBPγ as a novel antioxidant regulator and an obligatory ATF4 partner that controls redox homeostasis in normal and cancerous cells. PMID:26667036

  18. Regulation of Ras exchange factors and cellular localization of Ras activation by lipid messengers in T cells

    Directory of Open Access Journals (Sweden)

    Jesse E. Jun

    2013-09-01

    Full Text Available The Ras-MAPK signaling pathway is highly conserved throughout evolution and is activated downstream of a wide range of receptor stimuli. Ras guanine nucleotide exchange factors (RasGEFs catalyze GTP loading of Ras and play a pivotal role in regulating receptor-ligand induced Ras activity. In T cells, three families of functionally important RasGEFs are expressed: RasGRF, RasGRP, and SOS-family GEFs.Early on it was recognized that Ras activation is critical for T cell development and that the RasGEFs play an important role herein. More recent work has revealed that nuances in Ras activation appear to significantly impact T cell development and selection. These nuances include distinct biochemical patterns of analog versus digital Ras activation, differences in cellular localization of Ras activation, and intricate interplays between the RasGEFs during distinct T cell developmental stages as revealed by various new mouse models. In many instances, the exact nature of these nuances in Ras activation or how these may result from fine-tuning of the RasGEFs is not understood.One large group of biomolecules critically involved in the control of Ras-GEFs´functions are lipid second messengers. Multiple, yet distinct lipid products are generated following T cell receptor (TCR stimulation and bind to different domains in the RasGRP and SOS RasGEFs to facilitate the activation of the membrane-anchored Ras GTPases. In this review we highlight how different lipid-based elements are generated by various enzymes downstream of the TCR and other receptors and how these dynamic and interrelated lipid products may fine-tune Ras activation by RasGEFs in developing T cells.

  19. G-actin regulates rapid induction of actin nucleation by mDia1 to restore cellular actin polymers.

    Science.gov (United States)

    Higashida, Chiharu; Suetsugu, Shiro; Tsuji, Takahiro; Monypenny, James; Narumiya, Shuh; Watanabe, Naoki

    2008-10-15

    mDia1 belongs to the formin family of proteins that share FH1 and FH2 domains. Although formins play a critical role in the formation of many actin-based cellular structures, the physiological regulation of formin-mediated actin assembly within the cell is still unknown. Here we show that cells possess an acute actin polymer restoration mechanism involving mDia1. By using single-molecule live-cell imaging, we found that several treatments including low-dose G-actin-sequestering drugs and unpolymerizable actin mutants activate mDia1 to initiate fast directional movement. The FH2 region, the core domain for actin nucleation, is sufficient to respond to latrunculin B (LatB) to increase its actin nucleation frequency. Simulation analysis revealed an unexpected paradoxical effect of LatB that leads to a several fold increase in free G-actin along with an increase in total G-actin. These results indicate that in cells, the actin nucleation frequency of mDia1 is enhanced not only by Rho, but also strongly through increased catalytic efficiency of the FH2 domain. Consistently, frequent actin nucleation by mDia1 was found around sites of vigorous actin disassembly. Another major actin nucleator, the Arp2/3 complex, was not affected by the G-actin increase induced by LatB. Taken together, we propose that transient accumulation of G-actin works as a cue to promote mDia1-catalyzed actin nucleation to execute rapid reassembly of actin filaments.

  20. Allopurinol ameliorates thioacetamide-induced acute liver failure by regulating cellular redox-sensitive transcription factors in rats.

    Science.gov (United States)

    Demirel, Ulvi; Yalniz, Mehmet; Aygün, Cem; Orhan, Cemal; Tuzcu, Mehmet; Sahin, Kazim; Ozercan, Ibrahim Hanifi; Bahçecioğlu, Ibrahim Halil

    2012-08-01

    Oxidative stress plays important role in the development of acute liver failure. In this study, we investigated effects of allopurinol (AP) upon thioacetamide (TAA)-induced liver injury and the potential mechanisms leading to amelioration in inflammation with AP treatment. Acute liver failure was induced by intraperitoneal administration of TAA (300 mg/kg/day for 2 days). Thirty-five rats were divided into five groups as control (group 1), TAA (group 2), TAA + 25AP (group 3), TAA + 50 AP (group 4), and TAA + 100AP (group 5). The number of animals in each group was seven. At the end of the study, histopathological, biochemical, and western blot analysis were done. TAA treatment significantly increased serum levels of aminotransferases, liver malondialdehyde (MDA), nuclear factor-kappa B (NF-қB ), activator protein-1 (AP-1), tumor necrosis factor-alpha (TNF-α), cyclooxygenase-2 (COX-2) and interleukin-6 (IL-6) levels, and the necro-inflammation scores. Nevertheless, nuclear factor E2-related factor-2 and heme oxygenase-1 (HO-1) expressions in the liver were decreased by TAA. AP treatment significantly lowered the serum levels of aminotransferases (P < 0.01) and liver MDA, NF-κB, AP-1, TNF-α, COX-2, and IL-6 expressions (P < 0.05). Moreover, AP restored the liver Nrf2 and HO-1 expressions and improved the necro-inflammation scores significantly. AP improves oxidative stress-induced liver damage by regulating cellular redox-sensitive transcriptor factors and expression of pro-inflammatory and antioxidant defense mechanisms. AP probably exerts these beneficiary features by its free radical scavenging ability in a dose-dependent manner.

  1. 7 CFR 301.51-4 - Conditions governing the interstate movement of regulated articles from quarantined areas.

    Science.gov (United States)

    2010-01-01

    ... beetle; and (C) The article has not been combined or commingled with other articles so as to lose its... regulated articles from quarantined areas. 301.51-4 Section 301.51-4 Agriculture Regulations of the... of regulated articles from quarantined areas. (a) Any regulated article may be moved interstate...

  2. Coupling of Markov chains and cellular automata spatial models to predict land cover changes (case study: upper Ci Leungsi catchment area)

    Science.gov (United States)

    Marko, K.; Zulkarnain, F.; Kusratmoko, E.

    2016-11-01

    Land cover changes particular in urban catchment area has been rapidly occur. Land cover changes occur as a result of increasing demand for built-up area. Various kinds of environmental and hydrological problems e.g. floods and urban heat island can happen if the changes are uncontrolled. This study aims to predict land cover changes using coupling of Markov chains and cellular automata. One of the most rapid land cover changes is occurs at upper Ci Leungsi catchment area that located near Bekasi City and Jakarta Metropolitan Area. Markov chains has a good ability to predict the probability of change statistically while cellular automata believed as a powerful method in reading the spatial patterns of change. Temporal land cover data was obtained by remote sensing satellite imageries. In addition, this study also used multi-criteria analysis to determine which driving factor that could stimulate the changes such as proximity, elevation, and slope. Coupling of these two methods could give better prediction model rather than just using it separately. The prediction model was validated using existing 2015 land cover data and shown a satisfactory kappa coefficient. The most significant increasing land cover is built-up area from 24% to 53%.

  3. Alternative oxidase pathway optimizes photosynthesis during osmotic and temperature stress by regulating cellular ROS, malate valve and antioxidative systems

    Directory of Open Access Journals (Sweden)

    DINAKAR eCHALLABATHULA

    2016-02-01

    Full Text Available The present study reveals the importance of alternative oxidase (AOX pathway in optimizing photosynthesis under osmotic and temperature stress conditions in the mesophyll protoplasts of Pisum sativum. The responses of photosynthesis and respiration were monitored at saturating light intensity of 1000 µmoles m-2 s-1 at 25 oC under a range of sorbitol concentrations from 0.4 M to 1.0M to induce hyper-osmotic stress and by varying the temperature of the thermo-jacketed pre-incubation chamber from 25 oC to 10 oC to impose sub-optimal temperature stress. Compared to controls (0.4 M sorbitol and 25 OC, the mesophyll protoplasts showed remarkable decrease in NaHCO3-dependent O2 evolution (indicator of photosynthetic carbon assimilation, under both hyper-osmotic (1.0 M sorbitol and sub-optimal temperature stress conditions (10 OC, while the decrease in rates of respiratory O2 uptake were marginal. The capacity of AOX pathway increased significantly in parallel to increase in intracellular pyruvate and reactive oxygen species (ROS levels under both hyper-osmotic stress and sub-optimal temperature stress under the background of saturating light. The ratio of redox couple (Malate/OAA related to malate valve increased in contrast to the ratio of redox couple (GSH/GSSG related to antioxidative system during hyper-osmotic stress. Nevertheless, the ratio of GSH/GSSG decreased in the presence of sub-optimal temperature, while the ratio of Malate/OAA showed no visible changes. Also, the redox ratios of pyridine nucleotides increased under hyper-osmotic (NADH/NAD and sub-optimal temperature (NADPH/NADP stresses, respectively. However, upon restriction of AOX pathway by using salicylhydroxamic acid (SHAM, the observed changes in NaHCO3 dependent O2 evolution, cellular ROS, redox ratios of Malate/OAA, NAD(PH/NAD(P and GSH/GSSG were further aggravated under stress conditions with concomitant modulations in NADP-MDH and antioxidant enzymes. Taken together, the

  4. p53 increases intra-cellular calcium release by transcriptional regulation of calcium channel TRPC6 in GaQ3-treated cancer cells.

    Directory of Open Access Journals (Sweden)

    Esha Madan

    Full Text Available p53 and calcium signaling are inter-dependent and are known to show both synergistic and antagonistic effects on each other in the cellular environment. However, no molecular mechanism or cellular pathway is known which shows direct regulation between these important cellular signaling molecules. Here we have shown that in cancer cells treated with anti-neoplastic drug GaQ3, p53, there is an increase in intracellular calcium levels by transcriptional regulation of a novel calcium channel gene TRPC6. p53 directly binds to a 22 bp response element in the TRPC6 gene promoter and increase its mRNA and protein expression. Over-expression of TRPC6 results in calcium-dependent apoptotic death and activation of apoptotic genes in a variety of cancer cells. This research work shows that p53 and its transcriptional activity is critical in regulation of calcium signaling and an increase in the intracellular calcium level might be one of the anti-cancer strategies to induce apoptosis in cancer cells.

  5. Cellular transcriptional profiling in human lung epithelial cells infected by different subtypes of influenza A viruses reveals an overall down-regulation of the host p53 pathway

    Directory of Open Access Journals (Sweden)

    Lina Bruno

    2011-06-01

    Full Text Available Abstract Background Influenza viruses can modulate and hijack several cellular signalling pathways to efficiently support their replication. We recently investigated and compared the cellular gene expression profiles of human lung A549 cells infected by five different subtypes of human and avian influenza viruses (Josset et al. Plos One 2010. Using these transcriptomic data, we have focused our analysis on the modulation of the p53 pathway in response to influenza infection. Results Our results were supported by both RT-qPCR and western blot analyses and reveal multiple alterations of the p53 pathway during infection. A down-regulation of mRNA expression was observed for the main regulators of p53 protein stability during infection by the complete set of viruses tested, and a significant decrease in p53 mRNA expression was also observed in H5N1 infected cells. In addition, several p53 target genes were also down-regulated by these influenza viruses and the expression of their product reduced. Conclusions Our data reveal that influenza viruses cause an overall down-regulation of the host p53 pathway and highlight this pathway and p53 protein itself as important viral targets in the altering of apoptotic processes and in cell-cycle regulation.

  6. Postmitotic regulation of sensory area patterning in the mammalian neocortex by Lhx2.

    Science.gov (United States)

    Zembrzycki, Andreas; Perez-Garcia, Carlos G; Wang, Chia-Fang; Chou, Shen-Ju; O'Leary, Dennis D M

    2015-05-26

    Current knowledge suggests that cortical sensory area identity is controlled by transcription factors (TFs) that specify area features in progenitor cells and subsequently their progeny in a one-step process. However, how neurons acquire and maintain these features is unclear. We have used conditional inactivation restricted to postmitotic cortical neurons in mice to investigate the role of the TF LIM homeobox 2 (Lhx2) in this process and report that in conditional mutant cortices area patterning is normal in progenitors but strongly affected in cortical plate (CP) neurons. We show that Lhx2 controls neocortical area patterning by regulating downstream genetic and epigenetic regulators that drive the acquisition of molecular properties in CP neurons. Our results question a strict hierarchy in which progenitors dominate area identity, suggesting a novel and more comprehensive two-step model of area patterning: In progenitors, patterning TFs prespecify sensory area blueprints. Sequentially, sustained function of alignment TFs, including Lhx2, is essential to maintain and to translate the blueprints into functional sensory area properties in cortical neurons postmitotically. Our results reemphasize critical roles for Lhx2 that acts as one of the terminal selector genes in controlling principal properties of neurons.

  7. 7 CFR 301.75-9 - Interstate movement of regulated articles from a quarantined area for experimental or scientific...

    Science.gov (United States)

    2010-01-01

    ... Interstate movement of regulated articles from a quarantined area for experimental or scientific purposes. A... 7 Agriculture 5 2010-01-01 2010-01-01 false Interstate movement of regulated articles from a quarantined area for experimental or scientific purposes. 301.75-9 Section 301.75-9 Agriculture Regulations...

  8. 77 FR 53826 - Special Regulations; Areas of the National Park System, Yellowstone National Park

    Science.gov (United States)

    2012-09-04

    ... National Park Service 36 CFR Part 7 RIN 1024-AE10 Special Regulations; Areas of the National Park System, Yellowstone National Park AGENCY: National Park Service, Interior. ACTION: Proposed rule. SUMMARY: This rule... snowmobiles operating in the park to meet certain National Park Service air and sound emissions......

  9. 76 FR 39048 - Special Regulations; Areas of the National Park System, Yellowstone National Park

    Science.gov (United States)

    2011-07-05

    ... National Park Service 36 CFR Part 7 RIN 1024-AD92 Special Regulations; Areas of the National Park System, Yellowstone National Park AGENCY: National Park Service, Interior. ACTION: Proposed rule. SUMMARY: The National Park Service (NPS) is proposing this rule to establish a management framework that allows...

  10. 77 FR 73919 - Special Regulations; Areas of the National Park System, Yellowstone National Park

    Science.gov (United States)

    2012-12-12

    ... National Park Service 36 CFR Part 7 RIN 1024-AE10 Special Regulations; Areas of the National Park System, Yellowstone National Park AGENCY: National Park Service, Interior. ACTION: Final rule. SUMMARY: This rule... governs winter visitation and certain recreational activities in Yellowstone National Park for the...

  11. 76 FR 77131 - Special Regulations; Areas of the National Park System, Yellowstone National Park

    Science.gov (United States)

    2011-12-12

    ... National Park Service 36 CFR Part 7 RIN 1024-AD92 Special Regulations; Areas of the National Park System, Yellowstone National Park AGENCY: National Park Service, Interior. ACTION: Final rule. SUMMARY: This rule... winter visitation and certain recreational activities in Yellowstone National Park for the...

  12. A review of pesticide policies and regulations for urban amenity areas in seven European countries

    NARCIS (Netherlands)

    Kristoffersen, P.; Rask, A.M.; Grundy, A.; Franzen, I.; Kempenaar, C.; Raisio, J.; Schroeder, H.; Spijker, J.H.; Verschwele, A.; Zarina, L.

    2008-01-01

    An analysis of the regulations of herbicide use for weed control in non-agricultural/urban amenity areas, including actual pesticide use, was carried out as a joint survey of seven European countries: Denmark, Finland, Germany, Latvia, the Netherlands, Sweden and United Kingdom. Herbicides

  13. Excitatory amino acid receptors in the ventral tegmental area regulate dopamine release in the ventral striatum

    NARCIS (Netherlands)

    Karreman, M; Westerink, BHC; Moghaddam, B

    1996-01-01

    The role of excitatory amino acid (EAA) receptors located in the ventral tegmental area (VTA) in tonic and phasic regulation of dopamine release in the ventral striatum was investigated. Microdialysis in conscious rats was used to assess dopamine release primarily from the nucleus accumbens shell re

  14. 75 FR 1706 - Regulated Navigation Area; U.S. Navy Submarines, Hood Canal, WA

    Science.gov (United States)

    2010-01-13

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA11 Regulated Navigation Area; U.S. Navy Submarines, Hood... be in effect whenever any U.S. Navy submarine is operating in the Hood Canal and being escorted by the Coast Guard. The RNA is necessary to help ensure the safety and security of the submarines,...

  15. 33 CFR 165.1328 - Regulated Navigation Area; U.S. Navy submarines, Hood Canal, WA.

    Science.gov (United States)

    2010-07-01

    .... Navy submarines, Hood Canal, WA. 165.1328 Section 165.1328 Navigation and Navigable Waters COAST GUARD... § 165.1328 Regulated Navigation Area; U.S. Navy submarines, Hood Canal, WA. (a) Location. The following... whenever any U.S. Navy submarine is operating in the Hood Canal and is being escorted by the Coast...

  16. Accumulated SET protein up-regulates and interacts with hnRNPK, increasing its binding to nucleic acids, the Bcl-xS repression, and cellular proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Almeida, Luciana O.; Garcia, Cristiana B.; Matos-Silva, Flavia A. [Department of Clinical Analyses, Toxicology and Food Sciences, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP (Brazil); Curti, Carlos [Department of Physics and Chemistry, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP (Brazil); Leopoldino, Andréia M., E-mail: andreiaml@usp.br [Department of Clinical Analyses, Toxicology and Food Sciences, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP (Brazil)

    2014-02-28

    Highlights: • hnRNPK is a new target of SET. • SET regulates hnRNPK. • SET and hnRNPK accumulation promotes tumorigenesis. • SET accumulation is a potential model to study genes regulated by SET-hnRNPK. - Abstract: SET and hnRNPK are proteins involved in gene expression and regulation of cellular signaling. We previously demonstrated that SET accumulates in head and neck squamous cell carcinoma (HNSCC); hnRNPK is a prognostic marker in cancer. Here, we postulate that SET and hnRNPK proteins interact to promote tumorigenesis. We performed studies in HEK293 and HNSCC (HN6, HN12, and HN13) cell lines with SET/hnRNPK overexpression and knockdown, respectively. We found that SET and/or hnRNPK protein accumulation increased cellular proliferation. SET accumulation up-regulated hnRNPK mRNA and total/phosphorylated protein, promoted hnRNPK nuclear location, and reduced Bcl-x mRNA levels. SET protein directly interacted with hnRNPK, increasing both its binding to nucleic acids and Bcl-xS repression. We propose that hnRNPK should be a new target of SET and that SET–hnRNPK interaction, in turn, has potential implications in cell survival and malignant transformation.

  17. Cellular Automata Modelling in Predicting the Development of Settlement Areas, A Case Study in The Eastern District of Pontianak Waterfront City

    Science.gov (United States)

    Nurhidayati, E.; Buchori, I.; Mussadun; Fariz, T. R.

    2017-07-01

    Pontianak waterfront city as water-based urban has the potential of water resources, socio-economic, cultural, tourism and riverine settlements. Settlements areas in the eastern district of Pontianak waterfront city is located in the triangle of Kapuas river and Landak river. This study uses quantitative-GIS methods that integrates binary logistic regression and Cellular Automata-Markov models. The data used in this study such as satellite imagery Quickbird 2003, Ikonos 2008 and elevation contour interval 1 meter. This study aims to discover the settlement land use changes in 2003-2014 and to predict the settlements areas in 2020. This study results the accuracy in predicting of changes in settlements areas shows overall accuracy (79.74%) and the highest kappa index (0.55). The prediction results show that settlement areas (481.98 Ha) in 2020 and the increasingly of settlement areas (6.80 Ha/year) in 2014-2020. The development of settlement areas in 2020 shows the highest land expansion in Parit Mayor Village. The results of regression coefficient value (0) of flooding variable, so flooding did not influence to the development of settlement areas in the eastern district of Pontianak because the building’s adaptation of rumah panggung’s settlements was very good which have adjusted to the height of tidal flood.

  18. COX19 mediates the transduction of a mitochondrial redox signal from SCO1 that regulates ATP7A-mediated cellular copper efflux

    Science.gov (United States)

    Leary, Scot C.; Cobine, Paul A.; Nishimura, Tamiko; Verdijk, Robert M.; de Krijger, Ronald; de Coo, René; Tarnopolsky, Mark A.; Winge, Dennis R.; Shoubridge, Eric A.

    2013-01-01

    SCO1 and SCO2 are metallochaperones whose principal function is to add two copper ions to the catalytic core of cytochrome c oxidase (COX). However, affected tissues of SCO1 and SCO2 patients exhibit a combined deficiency in COX activity and total copper content, suggesting additional roles for these proteins in the regulation of cellular copper homeostasis. Here we show that both the redox state of the copper-binding cysteines of SCO1 and the abundance of SCO2 correlate with cellular copper content and that these relationships are perturbed by mutations in SCO1 or SCO2, producing a state of apparent copper overload. The copper deficiency in SCO patient fibroblasts is rescued by knockdown of ATP7A, a trans-Golgi, copper-transporting ATPase that traffics to the plasma membrane during copper overload to promote efflux. To investigate how a signal from SCO1 could be relayed to ATP7A, we examined the abundance and subcellular distribution of several soluble COX assembly factors. We found that COX19 partitions between mitochondria and the cytosol in a copper-dependent manner and that its knockdown partially rescues the copper deficiency in patient cells. These results demonstrate that COX19 is necessary for the transduction of a SCO1-dependent mitochondrial redox signal that regulates ATP7A-mediated cellular copper efflux. PMID:23345593

  19. GDF15 contributes to radioresistance and cancer stemness of head and neck cancer by regulating cellular reactive oxygen species via a SMAD-associated signaling pathway

    Science.gov (United States)

    Lee, Li-Yu; Fan, Kang-Hsing; Lu, Ya-Ching; Li, Yi-Chen; Chiang, Chang-Hsu; You, Guo-Rung; Chen, Hsin-Ying; Cheng, Ann-Joy

    2017-01-01

    Radiotherapy is an integral part for the treatment of head and neck cancer (HNC), while radioresistance is a major cause leads to treatment failure. GDF15, a member of the TGF-β superfamily, is hypothesized to participate in various types of homeostasis. However, the potential role of this molecule in regulation of radiosensitivity remains unclear. In this study, we demonstrated that GDF15 contributed to radioresistance of HNC, as determined by both gain- and lost-of-functional experiments. These results were achieved by the induction of mitochondrial membrane potential and suppression of intracellular reactive oxygen species (ROS). We further showed that GDF15 facilitated the conversion of cancer stemness, as assessed by the promotion of CD44+ and ALDH1+ cell populations and spheroid cell formation. At molecular level, GDF15 conferred to these cellular functions was through phosphorylated SMAD1 proteins to elite downstream signaling molecules. These cellular results were further confirmed in a tumor xenograft mouse study. Taken together, our results demonstrated that GDF15 contributed to radioresistance and cancer stemness by regulating cellular ROS levels via a SMAD-associated signaling pathway. GDF15 may serve as a prediction marker of radioresistance and a therapeutic target for the development of radio-sensitizing agents for the treatment of refractory HNC. PMID:27903972

  20. Prenatal thalamic waves regulate cortical area size prior to sensory processing

    Science.gov (United States)

    Moreno-Juan, Verónica; Filipchuk, Anton; Antón-Bolaños, Noelia; Mezzera, Cecilia; Gezelius, Henrik; Andrés, Belen; Rodríguez-Malmierca, Luis; Susín, Rafael; Schaad, Olivier; Iwasato, Takuji; Schüle, Roland; Rutlin, Michael; Nelson, Sacha; Ducret, Sebastien; Valdeolmillos, Miguel; Rijli, Filippo M.; López-Bendito, Guillermina

    2017-01-01

    The cerebral cortex is organized into specialized sensory areas, whose initial territory is determined by intracortical molecular determinants. Yet, sensory cortical area size appears to be fine tuned during development to respond to functional adaptations. Here we demonstrate the existence of a prenatal sub-cortical mechanism that regulates the cortical areas size in mice. This mechanism is mediated by spontaneous thalamic calcium waves that propagate among sensory-modality thalamic nuclei up to the cortex and that provide a means of communication among sensory systems. Wave pattern alterations in one nucleus lead to changes in the pattern of the remaining ones, triggering changes in thalamic gene expression and cortical area size. Thus, silencing calcium waves in the auditory thalamus induces Rorβ upregulation in a neighbouring somatosensory nucleus preluding the enlargement of the barrel-field. These findings reveal that embryonic thalamic calcium waves coordinate cortical sensory area patterning and plasticity prior to sensory information processing. PMID:28155854

  1. 75 FR 3333 - Irish Potatoes Grown in Colorado; Modification of the Handling Regulation for Area No. 2

    Science.gov (United States)

    2010-01-21

    ... the Committee recommending a temporary relaxation in the minimum size requirement. DATES: Effective... No. 3 only; regulation for Area No. 1 is currently not active. Grade, size, and maturity regulations...

  2. Cellular stress reactions assessed by gender and species in spiders from areas variously polluted with heavy metals.

    Science.gov (United States)

    Wilczek, Grazyna; Babczyńska, Agnieszka; Wilczek, Piotr; Dolezych, Bogdan; Migula, Paweł; Młyńska, Hanna

    2008-05-01

    In the funnel web spider Agelena labyrinthica (Agelenidae; A. l.), sheet web spider Linyphia triangularis (Linyphiidae; L. t.) and wolf spider Xerolycosa nemoralis (Lycosidae; X. n.) from two differently polluted meadow sites in southern Poland, we studied the relations between antioxidant parameters (glutathione, GSH; glutathione peroxidases, GPOX, GSTPx; catalase, CAT; stress proteins-Hsp70, metallothioneins Mts), the intensity of apoptosis and necrosis, and heavy metal burdens of the midgut gland. Cellular reactions against stress caused by pollutants seemed to be sex-dependent. The concentrations of Zn and Cu in the midgut glands of male A. l. and X. n. were more than double that of the females, from both study sites. In male spiders from the heavily polluted site, both negative correlations (activity of caspase-3-like proteins vs Cu, Zn concentration; number of depolarized mitochondria vs Cu concentration) and positive correlations (number of necrotic cells vs Cu concentrations; activity of CAT vs Zn ) were noted. The defense of males against high metal content and its prooxidative effects is based mainly on GSH and CAT. In females the antioxidative reactions are species-specific and depend mainly on high peroxidase activity and on stress protein level. The increase in the number of apoptotic cells in the midgut gland of female spiders from the heavily polluted site suggests the defensive role of this process in maintaining the proper functioning of this organ.

  3. Regulation of calnexin sub-cellular localization modulates endoplasmic reticulum stress-induced apoptosis in MCF-7 cells.

    Science.gov (United States)

    Delom, Frédéric; Fessart, Delphine; Chevet, Eric

    2007-02-01

    The endoplasmic reticulum (ER) is the cellular compartment where proteins enter the secretory pathway, undergo post-translational modifications and acquire a correct conformation. If these functions are chronically altered, specific ER stress signals are triggered to promote cell death through the intrinsic apoptotic pathway. Here, we show that tunicamycin causes significant alteration of calnexin sub-cellular distribution in MCF-7 cells. Interestingly, this correlates with the absence of both tunicamycin-induced calnexin phosphorylation as well as tunicamycin-induced cell death. Under these conditions, calnexin-associated Bap31, an ER integral membrane protein, is subjected to a caspase-8 cleavage pattern within a specific sub-compartment of the ER. These results suggest that MCF-7 resistance to ER stress-induced apoptosis is partially mediated by the expression level of calnexin which in turn controls its sub-cellular localization, and its association with Bap31. These data may delineate a resistance mechanism to the ER stress-induced intrinsic apoptotic pathway.

  4. Three Decades of Research on O-GlcNAcylation – A Major Nutrient Sensor that Regulates Signaling, Transcription and Cellular Metabolism.

    Directory of Open Access Journals (Sweden)

    Gerald W Hart

    2014-10-01

    Full Text Available Even though the dynamic modification of polypeptides by the monosaccharide, O-linked N-acetylglucosamine (O-GlcNAcylation was discovered over thirty-years ago, its physiological significance as a major nutrient sensor that regulates myriad cellular processes has only recently been more widely appreciated. O-GlcNAcylation, either on its own or by its interplay with other post-translational modifications, such as phosphorylation, ubiquitination and others, modulates the activities of signaling proteins, regulates most components of the transcription machinery, affects cell cycle progression and regulates the targeting/turnover or functions of myriad other regulatory proteins, in response to nutrients. Acute increases in O-GlcNAcylation protect cells from stress-induced injury, while chronic deregulation of O-GlcNAc cycling contributes to the etiology of major human diseases of aging, such as diabetes, cancer and neurodegeneration. Recent advances in tools to study O-GlcNAcylation at the individual site level and specific inhibitors of O-GlcNAc cycling have allowed more rapid progress toward elucidating the specific functions of O-GlcNAcylation in essential cellular processes.

  5. Plasma membrane Ca2+-ATPase isoforms composition regulates cellular pH homeostasis in differentiating PC12 cells in a manner dependent on cytosolic Ca2+ elevations.

    Directory of Open Access Journals (Sweden)

    Tomasz Boczek

    Full Text Available Plasma membrane Ca(2+-ATPase (PMCA by extruding Ca(2+ outside the cell, actively participates in the regulation of intracellular Ca(2+ concentration. Acting as Ca(2+/H(+ counter-transporter, PMCA transports large quantities of protons which may affect organellar pH homeostasis. PMCA exists in four isoforms (PMCA1-4 but only PMCA2 and PMCA3, due to their unique localization and features, perform more specialized function. Using differentiated PC12 cells we assessed the role of PMCA2 and PMCA3 in the regulation of intracellular pH in steady-state conditions and during Ca(2+ overload evoked by 59 mM KCl. We observed that manipulation in PMCA expression elevated pHmito and pHcyto but only in PMCA2-downregulated cells higher mitochondrial pH gradient (ΔpH was found in steady-state conditions. Our data also demonstrated that PMCA2 or PMCA3 knock-down delayed Ca(2+ clearance and partially attenuated cellular acidification during KCl-stimulated Ca(2+ influx. Because SERCA and NCX modulated cellular pH response in neglectable manner, and all conditions used to inhibit PMCA prevented KCl-induced pH drop, we considered PMCA2 and PMCA3 as mainly responsible for transport of protons to intracellular milieu. In steady-state conditions, higher TMRE uptake in PMCA2-knockdown line was driven by plasma membrane potential (Ψp. Nonetheless, mitochondrial membrane potential (Ψm in this line was dissipated during Ca(2+ overload. Cyclosporin and bongkrekic acid prevented Ψm loss suggesting the involvement of Ca(2+-driven opening of mitochondrial permeability transition pore as putative underlying mechanism. The findings presented here demonstrate a crucial role of PMCA2 and PMCA3 in regulation of cellular pH and indicate PMCA membrane composition important for preservation of electrochemical gradient.

  6. Plasma membrane Ca2+-ATPase isoforms composition regulates cellular pH homeostasis in differentiating PC12 cells in a manner dependent on cytosolic Ca2+ elevations.

    Science.gov (United States)

    Boczek, Tomasz; Lisek, Malwina; Ferenc, Bozena; Kowalski, Antoni; Stepinski, Dariusz; Wiktorska, Magdalena; Zylinska, Ludmila

    2014-01-01

    Plasma membrane Ca(2+)-ATPase (PMCA) by extruding Ca(2+) outside the cell, actively participates in the regulation of intracellular Ca(2+) concentration. Acting as Ca(2+)/H(+) counter-transporter, PMCA transports large quantities of protons which may affect organellar pH homeostasis. PMCA exists in four isoforms (PMCA1-4) but only PMCA2 and PMCA3, due to their unique localization and features, perform more specialized function. Using differentiated PC12 cells we assessed the role of PMCA2 and PMCA3 in the regulation of intracellular pH in steady-state conditions and during Ca(2+) overload evoked by 59 mM KCl. We observed that manipulation in PMCA expression elevated pHmito and pHcyto but only in PMCA2-downregulated cells higher mitochondrial pH gradient (ΔpH) was found in steady-state conditions. Our data also demonstrated that PMCA2 or PMCA3 knock-down delayed Ca(2+) clearance and partially attenuated cellular acidification during KCl-stimulated Ca(2+) influx. Because SERCA and NCX modulated cellular pH response in neglectable manner, and all conditions used to inhibit PMCA prevented KCl-induced pH drop, we considered PMCA2 and PMCA3 as mainly responsible for transport of protons to intracellular milieu. In steady-state conditions, higher TMRE uptake in PMCA2-knockdown line was driven by plasma membrane potential (Ψp). Nonetheless, mitochondrial membrane potential (Ψm) in this line was dissipated during Ca(2+) overload. Cyclosporin and bongkrekic acid prevented Ψm loss suggesting the involvement of Ca(2+)-driven opening of mitochondrial permeability transition pore as putative underlying mechanism. The findings presented here demonstrate a crucial role of PMCA2 and PMCA3 in regulation of cellular pH and indicate PMCA membrane composition important for preservation of electrochemical gradient.

  7. The Sec1/Munc18 protein Vps45 regulates cellular levels of its SNARE binding partners Tlg2 and Snc2 in Saccharomyces cerevisiae.

    Directory of Open Access Journals (Sweden)

    Scott G Shanks

    Full Text Available Intracellular membrane trafficking pathways must be tightly regulated to ensure proper functioning of all eukaryotic cells. Central to membrane trafficking is the formation of specific SNARE (soluble N-ethylmeleimide-sensitive factor attachment protein receptor complexes between proteins on opposing lipid bilayers. The Sec1/Munc18 (SM family of proteins play an essential role in SNARE-mediated membrane fusion, and like the SNAREs are conserved through evolution from yeast to humans. The SM protein Vps45 is required for the formation of yeast endosomal SNARE complexes and is thus essential for traffic through the endosomal system. Here we report that, in addition to its role in regulating SNARE complex assembly, Vps45 regulates cellular levels of its SNARE binding partners: the syntaxin Tlg2 and the v-SNARE Snc2: Cells lacking Vps45 have reduced cellular levels of Tlg2 and Snc2; and elevation of Vps45 levels results in concomitant increases in the levels of both Tlg2 and Snc2. As well as regulating traffic through the endosomal system, the Snc v-SNAREs are also required for exocytosis. Unlike most vps mutants, cells lacking Vps45 display multiple growth phenotypes. Here we report that these can be reversed by selectively restoring Snc2 levels in vps45 mutant cells. Our data indicate that as well as functioning as part of the machinery that controls SNARE complex assembly, Vps45 also plays a key role in determining the levels of its cognate SNARE proteins; another key factor in regulation of membrane traffic.

  8. Air quality in natural areas: interface between the public, science and regulation.

    Science.gov (United States)

    Percy, K E; Karnosky, D F

    2007-10-01

    Natural areas are important interfaces between air quality, the public, science and regulation. In the United States and Canada, national parks received over 315million visits during 2004. Many natural areas have been experiencing decreased visibility, increased ozone (O(3)) levels and elevated nitrogen deposition. Ozone is the most pervasive air pollutant in North American natural areas. There is an extensive scientific literature on O(3) exposure-tree response in chambered environments and, lately, free-air exposure systems. Yet, less is known about O(3) impacts on natural terrestrial ecosystems. To advance scientifically defensible O(3) risk assessment for natural forest areas, species-level measurement endpoints must be socially, economically and ecologically relevant. Exposure-based indices, based on appropriate final endpoints, present an underused opportunity to meet this need. Exposure-plant indices should have a high degree of statistical significance, have high goodness of fit, be biologically plausible and include confidence intervals to define uncertainty. They must be supported by exposure-response functions and be easy to use within an air quality regulation context. Ozone exposure-response indices developed within an ambient air context have great potential for improving risk assessment in natural forest areas and enhancing scientific literacy.

  9. The obesity-associated gene Negr1 regulates aspects of energy balance in rat hypothalamic areas.

    Science.gov (United States)

    Boender, Arjen J; van Gestel, Margriet A; Garner, Keith M; Luijendijk, Mieneke C M; Adan, Roger A H

    2014-07-01

    Neural growth regulator 1 (Negr1) is among the first common variants that have been associated with the regulation of body mass index. Using AAV technology directed to manipulate Negr1 expression in vivo, we find that decreased expression of Negr1 in periventricular hypothalamic areas leads to increases in body weight, presumably via increased food intake. Moreover, we observed that both increased and decreased levels of Negr1 lead to reduced locomotor activity and body temperature. In sum, our results provide further support for a role of hypothalamic expressed Negr1 in the regulation of energy balance. © 2014 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of the American Physiological Society and The Physiological Society.

  10. Independent Presynaptic and Postsynaptic Mechanisms Regulate Endocannabinoid Signaling at Multiple Synapses in the Ventral Tegmental Area

    OpenAIRE

    2004-01-01

    Dopamine (DA) neurons in the ventral tegmental area have been implicated in psychiatric disorders and drug abuse. Understanding the mechanisms through which their activity is regulated via the modulation of afferent input is imperative to understanding their roles in these conditions. Here we demonstrate that endocannabinoids liberated from DA neurons activate cannabinoid CB1 receptors located on glutamatergic axons and on GABAergic terminals targeting GABAB receptors located on these cells. ...

  11. The CPT1C 5'UTR contains a repressing upstream open reading frame that is regulated by cellular energy availability and AMPK.

    Directory of Open Access Journals (Sweden)

    Ines Lohse

    Full Text Available BACKGROUND: Translational control is utilized as a means of regulating gene expression in many species. In most cases, posttranscriptional regulatory mechanisms play an important role in stress response pathways and can lead to dysfunctional physiology if blocked by mutations. Carnitine Palmitoyltransferase 1 C (CPT1C, the brain-specific member of the CPT 1 family, has previously been shown to be involved in regulating metabolism in situations of energy surplus. PRINCIPAL FINDINGS: Sequence analysis of the CPT1C mRNA revealed that it contains an upstream open reading frame (uORF in the 5' UTR of its mRNA. Using CPT1C 5' UTR/luciferase constructs, we investigated the role of the uORF in translational regulation. The results presented here show that translation from the CPT1C main open reading frame (mORF is repressed by the presence of the uORF, that this repression is relieved in response to specific stress stimuli, namely glucose deprivation and palmitate-BSA treatment, and that AMPK inhibition can relieve this uORF-dependent repression. SIGNIFICANCE: The fact that the mORF regulation is relieved in response to a specific set of stress stimuli rather than general stress response, hints at an involvement of CPT1C in cellular energy-sensing pathways and provides further evidence for a role of CPT1C in hypothalamic regulation of energy homeostasis.

  12. Effect of Plant Growth Regulators on Leaf Number, Leaf Area and Leaf Dry Matter in Grape

    Directory of Open Access Journals (Sweden)

    Zahoor Ahmad BHAT

    2011-03-01

    Full Text Available Influence of phenylureas (CPPU and brassinosteriod (BR along with GA (gibberellic acid were studied on seedless grape vegetative characteristics like leaf number, leaf area and leaf dry matter. Growth regulators were sprayed on the vines either once (7 days after fruit set or 15 days after fruit set or twice (7+15 days after fruit set. CPPU 2 ppm+BR 0.4 ppm+GA 25 ppm produced maximum number of leaves (18.78 while as untreated vines produced least leaf number (16.22 per shoot. Maximum leaf area (129.70 cm2 and dry matter content (26.51% was obtained with higher CPPU (3 ppm and BR (0.4 ppm combination along with GA 25 ppm. Plant growth regulators whether naturally derived or synthetic are used to improve the productivity and quality of grapes. The relatively high value of grapes justifies more expensive inputs. A relatively small improvement in yield or fruit quality can justify the field application of a very costly product. Application of new generation growth regulators like brassinosteroids and phenylureas like CPPU have been reported to increase the leaf number as well as leaf area and dry matter thereby indirectly influencing the fruit yield and quality in grapes.

  13. A meta-analysis to evaluate the cellular processes regulated by the interactome of endogenous and over-expressed estrogen receptor alpha.

    Science.gov (United States)

    Simões, Joana; Amado, Francisco M; Vitorino, Rui; Helguero, Luisa A

    2015-01-01

    The nature of the proteins complexes that regulate ERα subcellular localization and activity is still an open question in breast cancer biology. Identification of such complexes will help understand development of endocrine resistance in ER+ breast cancer. Mass spectrometry (MS) has allowed comprehensive analysis of the ERα interactome. We have compared six published works analyzing the ERα interactome of MCF-7 and HeLa cells in order to identify a shared or different pathway-related fingerprint. Overall, 806 ERα interacting proteins were identified. The cellular processes were differentially represented according to the ERα purification methodology, indicating that the methodologies used are complementary. While in MCF-7 cells, the interactome of endogenous and over-expressed ERα essentially represents the same biological processes and cellular components, the proteins identified were not over-lapping; thus, suggesting that the biological response may differ as the regulatory/participating proteins in these complexes are different. Interestingly, biological processes uniquely associated to ERα over-expressed in HeLa cell line included L-serine biosynthetic process, cellular amino acid biosynthetic process and cell redox homeostasis. In summary, all the approaches analyzed in this meta-analysis are valid and complementary; in particular, for those cases where the processes occur at low frequency with normal ERα levels, and can be identified when the receptor is over-expressed. However special effort should be put into validating these findings in cells expressing physiological ERα levels.

  14. Mitigation of radiation-induced hematopoietic injury via regulation of cellular MAPK/phosphatase levels and increasing hematopoietic stem cells.

    Science.gov (United States)

    Patwardhan, R S; Sharma, Deepak; Checker, Rahul; Sandur, Santosh K

    2014-03-01

    Here we describe a novel strategy for mitigation of ionizing radiation-induced hematopoietic syndrome by suppressing the activity of MKP3, resulting in ERK activation and enhanced abundance of hematopoietic stem cells, using the antioxidant flavonoid baicalein (5,6,7-trihydroxyflavone). It offered complete protection to mouse splenic lymphocytes against radiation-induced cell death. Inhibitors of ERK and Nrf-2 could significantly abrogate baicalein-mediated radioprotection in lymphocytes. Baicalein inhibited phosphatase MKP3 and thereby enhanced phosphorylation of ERK and its downstream proteins such as Elk and Nrf-2. It also increased the nuclear levels of Nrf-2 and the mRNA levels of its dependent genes. Importantly, baicalein administration to mice before radiation exposure led to significant recovery of loss of bone marrow cellularity and also inhibited cell death. Administration of baicalein increased the hematopoietic stem cell frequency as measured by side-population assay and also by antibody staining. Further, baicalein offered significant protection against whole-body irradiation (WBI; 7.5Gy)-induced mortality in mice. Interestingly, we found that baicalein works by activating the same target molecules ERK and Nrf-2 both in vitro and in vivo. Finally, administration of all-trans-retinoic acid (inhibitor of Nrf-2) significantly abrogated baicalein-mediated protection against WBI-induced mortality in mice. Thus, in contrast to the generalized conception of antioxidants acting as radioprotectors, we provide a rationale that antioxidants exhibit pleiotropic effects through the activation of multiple cellular signaling pathways.

  15. Local mobilisation against windfarm developments in Spanish rural areas: New actors in the regulation arena

    Energy Technology Data Exchange (ETDEWEB)

    Moragues-Faus, Ana M., E-mail: anmofau@doctor.upv.es; Ortiz-Miranda, Dionisio

    2010-08-15

    The region of Valencia has a marked territorial duality: an urbanised, populated and high-income coastal line, and mountain and depressed inland rural areas. This territorial duality also derives in a functional duality, so that market and regulation drivers seem to assign rural areas specific roles for the provision of raw materials, energy, water, and the like. One of the clearest examples can be found in the design and development of the Wing Energy Plan passed by the Regional Government in 2001, which designated areas for the installation of windmills. However, this regulation has resulted in an outstanding emergence of associations that have organised at several levels (from the local to the national) as a strong opposition movement to the local developments of the Plan. With this background, the objective of this paper is to analyze, from a set of case studies, the processes of emergence and the evolution of collective actors (associations) which have been arising in many rural areas as a response to the local applications of the Wind Energy Plan. Attention will be paid to understand the tactics used, the process of adaptation to the participation mechanisms, and the role played by local and non-local networks.

  16. Local mobilisation against windfarm developments in Spanish rural areas. New actors in the regulation arena

    Energy Technology Data Exchange (ETDEWEB)

    Moragues-Faus, Ana M.; Ortiz-Miranda, Dionisio [Department of Economics and Social Sciences, Universidad Politecnica de Valencia, Camino de Vera s/n 46022 Valencia (Spain)

    2010-08-15

    The region of Valencia has a marked territorial duality: an urbanised, populated and high-income coastal line, and mountain and depressed inland rural areas. This territorial duality also derives in a functional duality, so that market and regulation drivers seem to assign rural areas specific roles for the provision of raw materials, energy, water, and the like. One of the clearest examples can be found in the design and development of the Wing Energy Plan passed by the Regional Government in 2001, which designated areas for the installation of windmills. However, this regulation has resulted in an outstanding emergence of associations that have organised at several levels (from the local to the national) as a strong opposition movement to the local developments of the Plan. With this background, the objective of this paper is to analyze, from a set of case studies, the processes of emergence and the evolution of collective actors (associations) which have been arising in many rural areas as a response to the local applications of the Wind Energy Plan. Attention will be paid to understand the tactics used, the process of adaptation to the participation mechanisms, and the role played by local and non-local networks. (author)

  17. Compound C prevents Hypoxia-Inducible Factor-1α protein stabilization by regulating the cellular oxygen availability via interaction with Mitochondrial Complex I

    Directory of Open Access Journals (Sweden)

    Hagen Thilo

    2011-04-01

    Full Text Available Abstract The transcription factor Hypoxia-Inducible Factor-1α is a master regulator of the cellular response to low oxygen concentration. Compound C, an inhibitor of AMP-activated kinase, has been reported to inhibit hypoxia dependent Hypoxia-Inducible Factor-1α activation via a mechanism that is independent of AMP-activated kinase but dependent on its interaction with the mitochondrial electron transport chain. The objective of this study is to characterize the interaction of Compound C with the mitochondrial electron transport chain and to determine the mechanism through which the drug influences the stability of the Hypoxia-Inducible Factor-1α protein. We found that Compound C functions as an inhibitor of complex I of the mitochondrial electron transport chain as demonstrated by its effect on mitochondrial respiration. It also prevents hypoxia-induced Hypoxia-Inducible Factor-1α stabilization in a dose dependent manner. In addition, Compound C does not have significant effects on reactive oxygen species production from complex I via both forward and reverse electron flux. This study provides evidence that similar to other mitochondrial electron transport chain inhibitors, Compound C regulates Hypoxia-Inducible Factor-1α stability by controlling the cellular oxygen concentration.

  18. Accumulated SET protein up-regulates and interacts with hnRNPK, increasing its binding to nucleic acids, the Bcl-xS repression, and cellular proliferation.

    Science.gov (United States)

    Almeida, Luciana O; Garcia, Cristiana B; Matos-Silva, Flavia A; Curti, Carlos; Leopoldino, Andréia M

    2014-02-28

    SET and hnRNPK are proteins involved in gene expression and regulation of cellular signaling. We previously demonstrated that SET accumulates in head and neck squamous cell carcinoma (HNSCC); hnRNPK is a prognostic marker in cancer. Here, we postulate that SET and hnRNPK proteins interact to promote tumorigenesis. We performed studies in HEK293 and HNSCC (HN6, HN12, and HN13) cell lines with SET/hnRNPK overexpression and knockdown, respectively. We found that SET and/or hnRNPK protein accumulation increased cellular proliferation. SET accumulation up-regulated hnRNPK mRNA and total/phosphorylated protein, promoted hnRNPK nuclear location, and reduced Bcl-x mRNA levels. SET protein directly interacted with hnRNPK, increasing both its binding to nucleic acids and Bcl-xS repression. We propose that hnRNPK should be a new target of SET and that SET-hnRNPK interaction, in turn, has potential implications in cell survival and malignant transformation.

  19. The MAP kinase-activated protein kinase Rck2p regulates cellular responses to cell wall stresses, filamentation and virulence in the human fungal pathogen Candida albicans.

    Science.gov (United States)

    Li, Xichuan; Du, Wei; Zhao, Jingwen; Zhang, Lilin; Zhu, Zhiyan; Jiang, Linghuo

    2010-06-01

    Rck2p is the Hog1p-MAP kinase-activated protein kinase required for the attenuation of protein synthesis in response to an osmotic challenge in Saccharomyces cerevisiae. Rck2p also regulates rapamycin sensitivity in both S. cerevisiae and Candida albicans. In this study, we demonstrate that the deletion of CaRCK2 renders C. albicans cells sensitive to, and CaRck2p translocates from the cytosol to the nucleus in response to, cell wall stresses caused by Congo red, Calcoflor White, elevated heat and zymolyase. However, the kinase activity of CaRck2p is not required for the cellular response to these cell wall stresses. Furthermore, transcripts of cell wall protein-encoding genes CaBGL2, CaHWP1 and CaXOG1 are reduced in C. albicans cells lacking CaRCK2. The deletion of CaRCK2 also reduces the in vitro filamentation of C. albicans and its virulence in a mouse model of systemic candidasis. The kinase activity of CaRck2p is required for the virulence, but not for the in vitro filamentation, in C. albicans. Therefore, Rck2p regulates cellular responses to cell wall stresses, filamentation and virulence in the human fungal pathogen C. albicans.

  20. New features on the environmental regulation of metabolism revealed by modeling the cellular proteomic adaptations induced by light, carbon and inorganic nitrogen in Chlamydomonas reinhardtii

    Directory of Open Access Journals (Sweden)

    Stéphanie Gérin

    2016-08-01

    Full Text Available Microalgae are currently emerging to be very promising organisms for the production of biofuels and high-added value compounds. Understanding the influence of environmental alterations on their metabolism is a crucial issue. Light, carbon and nitrogen availability have been reported to induce important metabolic adaptations. So far, the influence of these variables has essentially been studied while varying only one or two environmental factors at the same time. The goal of the present work was to model the cellular proteomic adaptations of the green microalga Chlamydomonas reinhardtii upon the simultaneous changes of light intensity, carbon concentrations (CO2 and acetate and inorganic nitrogen concentrations (nitrate and ammonium in the culture medium. Statistical design of experiments (DOE enabled to define 32 culture conditions to be tested experimentally. Relative protein abundance was quantified by two dimensional differential in-gel electrophoresis (2D-DIGE. Additional assays for respiration, photosynthesis, and lipid and pigment concentrations were also carried out. A hierarchical clustering survey enabled to partition biological variables (proteins + assays into eight co-regulated clusters. In most cases, the biological variables partitioned in the same cluster had already been reported to participate to common biological functions (acetate assimilation, bioenergetic processes, light harvesting, Calvin cycle and protein metabolism. The environmental regulation within each cluster was further characterized by a series of multivariate methods including principal component analysis and multiple linear regressions. This metadata analysis enabled to highlight the existence of a clear regulatory pattern for every cluster and to mathematically simulate the effects of light, carbon and nitrogen. The influence of these environmental variables on cellular metabolism is described in details and thoroughly discussed. This work provides an overview

  1. New Features on the Environmental Regulation of Metabolism Revealed by Modeling the Cellular Proteomic Adaptations Induced by Light, Carbon, and Inorganic Nitrogen in Chlamydomonas reinhardtii.

    Science.gov (United States)

    Gérin, Stéphanie; Leprince, Pierre; Sluse, Francis E; Franck, Fabrice; Mathy, Grégory

    2016-01-01

    Microalgae are currently emerging to be very promising organisms for the production of biofuels and high-added value compounds. Understanding the influence of environmental alterations on their metabolism is a crucial issue. Light, carbon and nitrogen availability have been reported to induce important metabolic adaptations. So far, the influence of these variables has essentially been studied while varying only one or two environmental factors at the same time. The goal of the present work was to model the cellular proteomic adaptations of the green microalga Chlamydomonas reinhardtii upon the simultaneous changes of light intensity, carbon concentrations (CO2 and acetate), and inorganic nitrogen concentrations (nitrate and ammonium) in the culture medium. Statistical design of experiments (DOE) enabled to define 32 culture conditions to be tested experimentally. Relative protein abundance was quantified by two dimensional differential in-gel electrophoresis (2D-DIGE). Additional assays for respiration, photosynthesis, and lipid and pigment concentrations were also carried out. A hierarchical clustering survey enabled to partition biological variables (proteins + assays) into eight co-regulated clusters. In most cases, the biological variables partitioned in the same cluster had already been reported to participate to common biological functions (acetate assimilation, bioenergetic processes, light harvesting, Calvin cycle, and protein metabolism). The environmental regulation within each cluster was further characterized by a series of multivariate methods including principal component analysis and multiple linear regressions. This metadata analysis enabled to highlight the existence of a clear regulatory pattern for every cluster and to mathematically simulate the effects of light, carbon, and nitrogen. The influence of these environmental variables on cellular metabolism is described in details and thoroughly discussed. This work provides an overview of the

  2. HIV-1 infection induces changes in expression of cellular splicing factors that regulate alternative viral splicing and virus production in macrophages

    Directory of Open Access Journals (Sweden)

    Purcell Damian FJ

    2008-02-01

    Full Text Available Abstract Background Macrophages are important targets and long-lived reservoirs of HIV-1, which are not cleared of infection by currently available treatments. In the primary monocyte-derived macrophage model of infection, replication is initially productive followed by a decline in virion output over ensuing weeks, coincident with a decrease in the levels of the essential viral transactivator protein Tat. We investigated two possible mechanisms in macrophages for regulation of viral replication, which appears to be primarily regulated at the level of tat mRNA: 1 differential mRNA stability, used by cells and some viruses for the rapid regulation of gene expression and 2 control of HIV-1 alternative splicing, which is essential for optimal viral replication. Results Following termination of transcription at increasing times after infection in macrophages, we found that tat mRNA did indeed decay more rapidly than rev or nef mRNA, but with similar kinetics throughout infection. In addition, tat mRNA decayed at least as rapidly in peripheral blood lymphocytes. Expression of cellular splicing factors in uninfected and infected macrophage cultures from the same donor showed an inverse pattern over time between enhancing factors (members of the SR family of RNA binding proteins and inhibitory factors (members of the hnRNP family. While levels of the SR protein SC35 were greatly up-regulated in the first week or two after infection, hnRNPs of the A/B and H groups were down-regulated. Around the peak of virus production in each culture, SC35 expression declined to levels in uninfected cells or lower, while the hnRNPs increased to control levels or above. We also found evidence for increased cytoplasmic expression of SC35 following long-term infection. Conclusion While no evidence of differential regulation of tat mRNA decay was found in macrophages following HIV-1 infection, changes in the balance of cellular splicing factors which regulate alternative

  3. SENP2 negatively regulates cellular antiviral response by deSUMOylating IRF3 and conditioning it for ubiquitination and degradation

    Institute of Scientific and Technical Information of China (English)

    Yong Ran; Tian-Tian Liu; Qian Zhou; Shu Li; Ai-Ping Mao; Ying Li; Li-Juan Liu; Jin-Ke Cheng; Hong-Bing Shu

    2011-01-01

    Transcription factor IRF3-mediated type I interferon induction is essential for antiviral innate immunity.We identified the deSUMOylating enzyme Sentrin/SUMO-specific protease (SENP) 2 as a negative regulator of virus-triggered IFN-β induction.Overexpression of SENP2 caused IRF3 deSUMOylation,K48-linked ubiquitination,and degradation,whereas depletion of SENP2 had opposite effects.Both the SUMOylation and K48-linked ubiquitination of IRF3 occurred at iysines 70 and 87,and these processes are competitive.The level of virus-triggered IFN-β was markedly up-regulated and viral replication was reduced in SENP2-deficient cells comparing with wild-type controls.Our findings suggest that SENP2 regulates antiviral innate immunity by deSUMOylating IRF3 and conditioning it for ubiquitination and degradation,and provide an example of cross-talk between the ubiquitin and SUMO pathways in innate immunity.%Transcription factor IRF3-mediated type I interferon induction is essential for antiviral innate immunity. We identified the deSUMOylating enzyme Sentrin/SUMO-specific protease (SENP) 2 as a negative regulator of virus-triggered IFN-p induction. Overexpression of SENP2 caused IRF3 deSUMOylation, K48-linked ubiquitination, and degradation, whereas depletion of SENP2 had opposite effects. Both the SUMOylation and K48-linked ubiquitination of IRF3 occurred at lysines 70 and 87, and these processes are competitive. The level of virus-triggered IFN-β was markedly up-regulated and viral replication was reduced in SENP2-deficient cells comparing with wild-type controls. Our findings suggest that SENP2 regulates antiviral innate immunity by deSUMOylating IRF3 and conditioning it for ubiquitination and degradation, and provide an example of cross-talk between the ubiquitin and SUMO pathways in innate immunity.

  4. Elevated glutathione levels confer cellular sensitization to cisplatin toxicity by up-regulation of copper transporter hCtr1.

    Science.gov (United States)

    Chen, Helen H W; Song, Im-Sook; Hossain, Anwar; Choi, Min-Koo; Yamane, Yoshiaki; Liang, Zheng D; Lu, Jia; Wu, Lily Y-H; Siddik, Zahid H; Klomp, Leo W J; Savaraj, Niramol; Kuo, Macus Tien

    2008-09-01

    Previous studies have demonstrated that treating cultured cells with cisplatin (CDDP) up-regulated the expression of glutathione (GSH) and its de novo rate-limiting enzyme glutamate-cysteine ligase (GCL), which consists of a catalytic (GCLC) and a modifier (GCLM) subunit. It has also been shown that many CDDP-resistant cell lines exhibit high levels of GCLC/GCLM and GSH. Because the GSH system is the major intracellular regulator of redox conditions that serve as an important detoxification cytoprotector, these results have been taken into consideration that elevated levels of GCL/GSH are responsible for the CDDP resistance. In contrast to this context, we demonstrated here that overexpression of GSH by transfection with an expression plasmid containing the GCLC cDNA conferred sensitization to CDDP through up-regulation of human copper transporter (hCtr) 1, which is also a transporter for CDDP. Depleting GSH levels in these transfected cells reversed CDDP sensitivity with concomitant reduction of hCtr1 expression. Although rates of copper transport were also up-regulated in the transfected cells, these cells exhibited biochemical signature of copper deficiency, suggesting that GSH functions as an intracellular copper-chelator and that overexpression of GSH can alter copper metabolism. More importantly, our results reveal a new role of GSH in the regulation of CDDP sensitivity. Overproduction of GSH depletes the bioavailable copper pool, leading to up-regulation of hCtr1 and sensitization of CDDP transport and cell killing. These findings also have important implications in that modulation of the intracellular copper pool may be a novel strategy for improving chemotherapeutic efficacy of platinum-based antitumor agents.

  5. 75 FR 76280 - Regulated Navigation Area; Thea Foss and Wheeler-Osgood Waterways EPA Superfund Cleanup Site...

    Science.gov (United States)

    2010-12-08

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA11 Regulated Navigation Area; Thea Foss and Wheeler-Osgood... of the Thea Foss and Wheeler-Osgood Waterways in Commencement Bay, Tacoma, Washington. The RNA will... notice of proposed rulemaking (SNPRM) entitled Regulated Navigation Area; Thea Foss and Wheeler-Osgood...

  6. 75 FR 30753 - Regulated Navigation Area; Thea Foss and Wheeler-Osgood Waterways EPA Superfund Cleanup Site...

    Science.gov (United States)

    2010-06-02

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA11 Regulated Navigation Area; Thea Foss and Wheeler-Osgood... and Wheeler-Osgood Waterways in Commencement Bay, Tacoma, Washington. The RNA would protect the seabed... rulemaking (NPRM) entitled ``Regulated Navigation Area; Thea Foss and Wheeler-Osgood Waterways EPA...

  7. Interhemispheric claustral circuits coordinate somatomotor and visuomotor cortical areas that regulate exploratory behaviors

    Directory of Open Access Journals (Sweden)

    Jared Brent Smith

    2014-05-01

    Full Text Available The claustrum has a role in the interhemispheric transfer of certain types of sensorimotor information. Whereas the whisker region in rat motor (M1 cortex sends dense projections to the contralateral claustrum, the M1 forelimb representation does not. The claustrum sends strong ipsilateral projections to the whisker regions in M1 and somatosensory (S1 cortex, but its projections to the forelimb cortical areas are weak. These distinctions suggest that one function of the M1 projections to the contralateral claustrum is to coordinate the cortical areas that regulate peripheral sensor movements during behaviors that depend on bilateral sensory acquisition. If this hypothesis is true, then similar interhemispheric circuits should interconnect the frontal eye fields (FEF with the contralateral claustrum and its network of projections to vision-related cortical areas. To test this hypothesis, anterograde and retrograde tracers were placed in physiologically-defined parts of the FEF and primary visual cortex (V1 in rats. We observed dense FEF projections to the contralateral claustrum that terminated in the midst of claustral neurons that project to both FEF and V1. While the FEF inputs to the claustrum come predominantly from the contralateral hemisphere, the claustral projections to FEF and V1 are primarily ipsilateral. Detailed comparison of the present results with our previous studies on somatomotor claustral circuitry revealed a well-defined functional topography in which the ventral claustrum is connected with visuomotor cortical areas and the dorsal regions are connected with somatomotor areas. These results suggest that subregions within the claustrum play a critical role in coordinating the cortical areas that regulate the acquisition of modality-specific sensory information during exploration and other behaviors that require sensory attention.

  8. The telomeric protein AKTIP interacts with A- and B-type lamins and is involved in regulation of cellular senescence

    Science.gov (United States)

    Burla, Romina; Carcuro, Mariateresa; Torre, Mattia La; Fratini, Federica; Crescenzi, Marco; D'Apice, Maria Rosaria; Spitalieri, Paola; Raffa, Grazia Daniela; Astrologo, Letizia; Lattanzi, Giovanna; Cundari, Enrico; Raimondo, Domenico; Biroccio, Annamaria; Gatti, Maurizio

    2016-01-01

    AKTIP is a shelterin-interacting protein required for replication of telomeric DNA. Here, we show that AKTIP biochemically interacts with A- and B-type lamins and affects lamin A, but not lamin C or B, expression. In interphase cells, AKTIP localizes at the nuclear rim and in discrete regions of the nucleoplasm just like lamins. Double immunostaining revealed that AKTIP partially co-localizes with lamin B1 and lamin A/C in interphase cells, and that proper AKTIP localization requires functional lamin A. In mitotic cells, AKTIP is enriched at the spindle poles and at the midbody of late telophase cells similar to lamin B1. AKTIP-depleted cells show senescence-associated markers and recapitulate several aspects of the progeroid phenotype. Collectively, our results indicate that AKTIP is a new player in lamin-related processes, including those that govern nuclear architecture, telomere homeostasis and cellular senescence. PMID:27512140

  9. Novel metastasis-related gene CIM functions in the regulation of multiple cellular stress-response pathways.

    Science.gov (United States)

    Yanagisawa, Kiyoshi; Konishi, Hiroyuki; Arima, Chinatsu; Tomida, Shuta; Takeuchi, Toshiyuki; Shimada, Yukako; Yatabe, Yasushi; Mitsudomi, Tetsuya; Osada, Hirotaka; Takahashi, Takashi

    2010-12-01

    Various stresses of the tumor microenvironment produced by insufficient nutrients, pH, and oxygen can contribute to the generation of altered metabolic and proliferative states that promote the survival of metastatic cells. Among many cellular stress-response pathways activated under such conditions are the hypoxia-inducible factor (HIF) pathway and the unfolded protein response (UPR), which is elicited as a response to endoplasmic reticulum (ER) stress. In this study, we report the identification of a novel cancer invasion and metastasis-related gene (hereafter referred to as CIM, also called ERLEC1), which influences both of these stress-response pathways to promote metastasis. CIM was identified by comparing the gene expression profile of a highly metastatic human lung cancer cell line with its weakly metastatic parental clone. We showed that CIM is critical for metastatic properties in this system. Proteomic approaches combined with bioinformatic analyses revealed that CIM has multifaceted roles in controlling the response to hypoxia and ER stress. Specifically, CIM sequestered OS-9 from the HIF-1α complex and PHD2, permitting HIF-1α accumulation by preventing its degradation. Ectopic expression of CIM in lung cancer cells increased their tolerance to hypoxia. CIM also modulated UPR through interaction with the key ER stress protein BiP, influencing cell proliferation under ER stress conditions. Our findings shed light on how tolerance to multiple cellular stresses at a metastatic site can be evoked by an integrated mechanism involving CIM, which can function to coordinate those responses in a manner that promotes metastatic cell survival.

  10. Cellular concentrations of DDB2 regulate dynamic binding of DDB1 at UV-induced DNA damage

    NARCIS (Netherlands)

    Alekseev, S.; Luijsterburg, M.S.; Pines, A.; Geverts, B.; Mari, P.-O.; Giglia-Mari, G.; Lans, H.; Houtsmuller, A.B.; Mullenders, L.H.F.; Hoeijmakers, J.H.J.; Vermeulen, W.

    2008-01-01

    Nucleotide excision repair (NER) is the principal pathway for counteracting cytotoxic and mutagenic effects of UV irradiation. To provide insight into the in vivo regulation of the DNA damage recognition step of global genome NER (GG-NER), we constructed cell lines expressing fluorescently tagged da

  11. HSCARG negatively regulates the cellular antiviral RIG-I like receptor signaling pathway by inhibiting TRAF3 ubiquitination via recruiting OTUB1.

    Directory of Open Access Journals (Sweden)

    Yanyan Peng

    2014-04-01

    Full Text Available RIG-I like receptors (RLRs recognize cytosolic viral RNA and initiate innate immunity; they increase the production of type I interferon (IFN and the transcription of a series of antiviral genes to protect the host organism. Accurate regulation of the RLR pathway is important for avoiding tissue injury induced by excessive immune response. HSCARG is a newly reported negative regulator of NF-κB. Here we demonstrated that HSCARG participates in innate immunity. HSCARG inhibited the cellular antiviral response in an NF-κB independent manner, whereas deficiency of HSCARG had an opposite effect. After viral infection, HSCARG interacted with tumor necrosis receptor-associated factor 3 (TRAF3 and inhibited its ubiquitination by promoting the recruitment of OTUB1 to TRAF3. Knockout of HSCARG attenuated the de-ubiquitination of TRAF3 by OTUB1, and knockdown of OTUB1 abolished the effect of HSCARG. HSCARG also interacted with Ikappa-B kinase epsilon (IKKε after viral infection and impaired the association between TRAF3 and IKKε, which further decreased the phosphorylation of IKKε and interferon response factor 3 (IRF3, thus suppressed the dimerization and nuclear translocation of IRF3. Moreover, knockdown of TRAF3 dampened the inhibitory effect of IFN-β transcription by HSCARG, suggesting that TRAF3 is necessary for HSCARG to down-regulate RLR pathway. This study demonstrated that HSCARG is a negative regulator that enables balanced antiviral innate immunity.

  12. Krüppel-like factors 4 and 5: the yin and yang regulators of cellular proliferation

    Institute of Scientific and Technical Information of China (English)

    Amr M.GHALEB; Mandayam O.NANDAN; Sengthong CHANCHEVALAP; W.Brian DALTON; Irfan M.HISAMUDDIN; Vincent W.YANG

    2005-01-01

    Krüppel-like factors (KLFs) are evolutionarily conserved zinc finger-containing transcription factors with diverse regulatory functions in cell growth, proliferation, differentiation, and embryogenesis. KLF4 and KLF5 are two closely related members of the KLF family that have a similar tissue distribution in embryos and adults. However, the two KLFs often exhibit opposite effects on regulation of gene transcription, despite binding to similar, if not identical, cis-acting DNA sequences. In addition, KLF4 and 5 exert contrasting effects on cell proliferation in many instances; while KLF4is an inhibitor of cell growth, KLF5 stimulates proliferation. Here we review the biological properties and biochemical mechanisms of action of the two KLFs in the context of growth regulation.

  13. Emerging roles for the amyloid precursor protein and derived peptides in the regulation of cellular and systemic metabolism.

    Science.gov (United States)

    Czeczor, Juliane K; McGee, Sean L

    2017-03-28

    The amyloid precursor protein (APP) is a transmembrane protein that can be cleaved by proteases through two different pathways to yield a number of small peptides, each with distinct physiological properties and functions. It has been extensively studied in the context of Alzheimer's disease, with the APP-derived amyloid beta (Aβ) peptide being a major constituent of the amyloid plaques observed in this disease. It has been known for some time that APP can regulate neuronal metabolism, however this review will examine evidence that APP and its peptides can also regulate key metabolic processes such as insulin action, lipid synthesis and storage and mitochondrial function in peripheral tissues. This review will present a hypothesis that amyloidogenic processing of APP in peripheral tissues plays a key role in the response to nutrient excess and that this could contribute to the pathogenesis of metabolic diseases such as obesity and type 2 diabetes (T2D). This article is protected by copyright. All rights reserved.

  14. Independent presynaptic and postsynaptic mechanisms regulate endocannabinoid signaling at multiple synapses in the ventral tegmental area.

    Science.gov (United States)

    Riegel, Arthur C; Lupica, Carl R

    2004-12-08

    Dopamine (DA) neurons in the ventral tegmental area have been implicated in psychiatric disorders and drug abuse. Understanding the mechanisms through which their activity is regulated via the modulation of afferent input is imperative to understanding their roles in these conditions. Here we demonstrate that endocannabinoids liberated from DA neurons activate cannabinoid CB1 receptors located on glutamatergic axons and on GABAergic terminals targeting GABA(B) receptors located on these cells. Endocannabinoid release was initiated by inhibiting either presynaptic type-III metabotropic glutamate receptors or postsynaptic calcium-activated potassium channels, two conditions that also promote enhanced DA neuron excitability and bursting. Thus, activity-dependent release of endocannabinoids may act as a regulatory feedback mechanism to inhibit synaptic inputs in response to DA neuron bursting, thereby regulating firing patterns that may fine-tune DA release from afferent terminals.

  15. Ki-1/57 and CGI-55 ectopic expression impact cellular pathways involved in proliferation and stress response regulation.

    Science.gov (United States)

    Costa, Fernanda C; Saito, Angela; Gonçalves, Kaliandra A; Vidigal, Pedro M; Meirelles, Gabriela V; Bressan, Gustavo C; Kobarg, Jörg

    2014-12-01

    Ki-1/57 (HABP4) and CGI-55 (SERBP1) are regulatory proteins and paralogs with 40.7% amino acid sequence identity and 67.4% similarity. Functionally, they have been implicated in the regulation of gene expression on both the transcriptional and mRNA metabolism levels. A link with tumorigenesis is suggested, since both paralogs show altered expression levels in tumor cells and the Ki-1/57 gene is found in a region of chromosome 9q that represents a haplotype for familiar colon cancer. However, the target genes regulated by Ki-1/57 and CGI-55 are unknown. Here, we analyzed the alterations of the global transcriptome profile after Ki-1/57 or CGI-55 overexpression in HEK293T cells by DNA microchip technology. We were able to identify 363 or 190 down-regulated and 50 or 27 up-regulated genes for Ki-1/57 and CGI-55, respectively, of which 20 were shared between both proteins. Expression levels of selected genes were confirmed by qRT-PCR both after protein overexpression and siRNA knockdown. The majority of the genes with altered expression were associated to proliferation, apoptosis and cell cycle control processes, prompting us to further explore these contexts experimentally. We observed that overexpression of Ki-1/57 or CGI-55 results in reduced cell proliferation, mainly due to a G1 phase arrest, whereas siRNA knockdown of CGI-55 caused an increase in proliferation. In the case of Ki-1/57 overexpression, we found protection from apoptosis after treatment with the ER-stress inducer thapsigargin. Together, our data give important new insights that may help to explain these proteins putative involvement in tumorigenic events. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Versatile assays for high throughput screening for activators or inhibitors of intracellular proteases and their cellular regulators.

    Directory of Open Access Journals (Sweden)

    Hideki Hayashi

    Full Text Available Intracellular proteases constitute a class of promising drug discovery targets. Methods for high throughput screening against these targets are generally limited to in vitro biochemical assays that can suffer many technical limitations, as well as failing to capture the biological context of proteases within the cellular pathways that lead to their activation. METHODS #ENTITYSTARTX00026;We describe here a versatile system for reconstituting protease activation networks in yeast and assaying the activity of these pathways using a cleavable transcription factor substrate in conjunction with reporter gene read-outs. The utility of these versatile assay components and their application for screening strategies was validated for all ten human Caspases, a family of intracellular proteases involved in cell death and inflammation, including implementation of assays for high throughput screening (HTS of chemical libraries and functional screening of cDNA libraries. The versatility of the technology was also demonstrated for human autophagins, cysteine proteases involved in autophagy.Altogether, the yeast-based systems described here for monitoring activity of ectopically expressed mammalian proteases provide a fascile platform for functional genomics and chemical library screening.

  17. Second-Life Batteries on a Gas Turbine Power Plant to Provide Area Regulation Services

    Directory of Open Access Journals (Sweden)

    Lluc Canals Casals

    2017-03-01

    Full Text Available Batteries are used in the electricity grid to provide ancillary services. Area regulation seems to provide substantial revenues and profit, but Li-ion batteries are still too expensive to enter widely into this market. On the other hand, electric vehicle (EV batteries are considered inappropriate for traction purposes when they reach a state of health (SoH of 80%. The reuse of these batteries offers affordable batteries for second-life stationary applications. This study analyzes two possible scenarios where batteries may give power and energy support to a gas turbine cogeneration power plant, and how long these batteries may last under different loads.

  18. Down-regulation of cellular FLICE-inhibitory protein (Long Form contributes to apoptosis induced by Hsp90 inhibition in human lung cancer cells

    Directory of Open Access Journals (Sweden)

    Wang Qilin

    2012-12-01

    Full Text Available Abstract Background Cellular FLICE-Inhibitory Protein (long form, c-FLIPL is a critical negative regulator of death receptor-mediated apoptosis. Overexpression of c-FLIPL has been reported in many cancer cell lines and is associated with chemoresistance. In contrast, down-regulation of c-FLIP may drive cancer cells into cellular apoptosis. This study aims to demonstrate that inhibition of the heat shock protein 90 (Hsp90 either by inhibitors geldanamycin/17-N-Allylamino-17-demethoxygeldanamycin (GA/17-AAG or siRNA technique in human lung cancer cells induces c-FLIPL degradation and cellular apoptosis through C-terminus of Hsp70-interacting protein (CHIP-mediated mechanisms. Methods Calu-1 and H157 cell lines (including H157-c-FLIPL overexpressing c-FLIPL and control cell H157-lacZ were treated with 17-AAG and the cell lysates were prepared to detect the given proteins by Western Blot and the cell survival was assayed by SRB assay. CHIP and Hsp90 α/β proteins were knocked down by siRNA technique. CHIP and c-FLIPL plasmids were transfected into cells and immunoprecipitation experiments were performed to testify the interactions between c-FLIPL, CHIP and Hsp90. Results c-FLIPL down-regulation induced by 17-AAG can be reversed with the proteasome inhibitor MG132, which suggested that c-FLIPL degradation is mediated by a ubiquitin-proteasome system. Inhibition of Hsp90α/β reduced c-FLIPL level, whereas knocking down CHIP expression with siRNA technique inhibited c-FLIPL degradation. Furthermore, c-FLIPL and CHIP were co-precipitated in the IP complexes. In addition, overexpression of c-FLIPL can rescue cancer cells from apoptosis. When 17-AAG was combined with an anti-cancer agent celecoxib(CCB, c-FLIPL level declined further and there was a higher degree of caspase activation. Conclusion We have elucidated c-FLIPL degradation contributes to apoptosis induced by Hsp90 inhibition, suggesting c-FLIP and Hsp90 may be the promising combined targets

  19. The vacuolar-ATPase complex and assembly factors, TMEM199 and CCDC115, control HIF1α prolyl hydroxylation by regulating cellular iron levels.

    Science.gov (United States)

    Miles, Anna L; Burr, Stephen P; Grice, Guinevere L; Nathan, James A

    2017-03-15

    Hypoxia Inducible transcription Factors (HIFs) are principally regulated by the 2-oxoglutarate and Iron(II) prolyl hydroxylase (PHD) enzymes, which hydroxylate the HIFα subunit, facilitating its proteasome-mediated degradation. Observations that HIFα hydroxylation can be impaired even when oxygen is sufficient emphasise the importance of understanding the complex nature of PHD regulation. Here, we use an unbiased genome-wide genetic screen in near-haploid human cells to uncover cellular processes that regulate HIF1α. We identify that genetic disruption of the Vacuolar H+ ATPase (V-ATPase), the key proton pump for endo-lysosomal acidification, and two previously uncharacterised V-ATPase assembly factors, TMEM199 and CCDC115, stabilise HIF1α in aerobic conditions. Rather than preventing the lysosomal degradation of HIF1α, disrupting the V-ATPase results in intracellular iron depletion, thereby impairing PHD activity and leading to HIF activation. Iron supplementation directly restores PHD catalytic activity following V-ATPase inhibition, revealing important links between the V-ATPase, iron metabolism and HIFs.

  20. Cellular inhibitor of apoptosis protein-1 (cIAP1) can regulate E2F1 transcription factor-mediated control of cyclin transcription.

    Science.gov (United States)

    Cartier, Jessy; Berthelet, Jean; Marivin, Arthur; Gemble, Simon; Edmond, Valérie; Plenchette, Stéphanie; Lagrange, Brice; Hammann, Arlette; Dupoux, Alban; Delva, Laurent; Eymin, Béatrice; Solary, Eric; Dubrez, Laurence

    2011-07-29

    The inhibitor of apoptosis protein cIAP1 (cellular inhibitor of apoptosis protein-1) is a potent regulator of the tumor necrosis factor (TNF) receptor family and NF-κB signaling pathways in the cytoplasm. However, in some primary cells and tumor cell lines, cIAP1 is expressed in the nucleus, and its nuclear function remains poorly understood. Here, we show that the N-terminal part of cIAP1 directly interacts with the DNA binding domain of the E2F1 transcription factor. cIAP1 dramatically increases the transcriptional activity of E2F1 on synthetic and CCNE promoters. This function is not conserved for cIAP2 and XIAP, which are cytoplasmic proteins. Chromatin immunoprecipitation experiments demonstrate that cIAP1 is recruited on E2F binding sites of the CCNE and CCNA promoters in a cell cycle- and differentiation-dependent manner. cIAP1 silencing inhibits E2F1 DNA binding and E2F1-mediated transcriptional activation of the CCNE gene. In cells that express a nuclear cIAP1 such as HeLa, THP1 cells and primary human mammary epithelial cells, down-regulation of cIAP1 inhibits cyclin E and A expression and cell proliferation. We conclude that one of the functions of cIAP1 when localized in the nucleus is to regulate E2F1 transcriptional activity.

  1. A quantitative analysis of L-glutamate-regulated Na+ dynamics in mouse cortical astrocytes: implications for cellular bioenergetics.

    Science.gov (United States)

    Chatton, J Y; Marquet, P; Magistretti, P J

    2000-11-01

    The mode of Na+ entry and the dynamics of intracellular Na+ concentration ([Na+]i) changes consecutive to the application of the neurotransmitter glutamate were investigated in mouse cortical astrocytes in primary culture by video fluorescence microscopy. An elevation of [Na+]i was evoked by glutamate, whose amplitude and initial rate were concentration dependent. The glutamate-evoked Na+ increase was primarily due to Na+-glutamate cotransport, as inhibition of non-NMDA ionotropic receptors by 6-cyano-7-nitroquinoxiline-2,3-dione (CNQX) only weakly diminished the response and D-aspartate, a substrate of the glutamate transporter, produced [Na+]i elevations similar to those evoked by glutamate. Non-NMDA receptor activation could nevertheless be demonstrated by preventing receptor desensitization using cyclothiazide. Thus, in normal conditions non-NMDA receptors do not contribute significantly to the glutamate-evoked Na+ response. The rate of Na+ influx decreased during glutamate application, with kinetics that correlate well with the increase in [Na+]i and which depend on the extracellular concentration of glutamate. A tight coupling between Na+ entry and Na+/K+ ATPase activity was revealed by the massive [Na+]i increase evoked by glutamate when pump activity was inhibited by ouabain. During prolonged glutamate application, [Na+]i remains elevated at a new steady-state where Na+ influx through the transporter matches Na+ extrusion through the Na+/K+ ATPase. A mathematical model of the dynamics of [Na+]i homeostasis is presented which precisely defines the critical role of Na+ influx kinetics in the establishment of the elevated steady state and its consequences on the cellular bioenergetics. Indeed, extracellular glutamate concentrations of 10 microM already markedly increase the energetic demands of the astrocytes.

  2. VEGF-A Regulates Cellular Localization of SR-BI as Well as Transendothelial Transport of HDL but Not LDL.

    Science.gov (United States)

    Velagapudi, Srividya; Yalcinkaya, Mustafa; Piemontese, Antonio; Meier, Roger; Nørrelykke, Simon Flyvbjerg; Perisa, Damir; Rzepiela, Andrzej; Stebler, Michael; Stoma, Szymon; Zanoni, Paolo; Rohrer, Lucia; von Eckardstein, Arnold

    2017-05-01

    Low- and high-density lipoproteins (LDL and HDL) must pass the endothelial layer to exert pro- and antiatherogenic activities, respectively, within the vascular wall. However, the rate-limiting factors that mediate transendothelial transport of lipoproteins are yet little known. Therefore, we performed a high-throughput screen with kinase drug inhibitors to identify modulators of transendothelial LDL and HDL transport. Microscopy-based high-content screening was performed by incubating human aortic endothelial cells with 141 kinase-inhibiting drugs and fluorescent-labeled LDL or HDL. Inhibitors of vascular endothelial growth factor (VEGF) receptors (VEGFR) significantly decreased the uptake of HDL but not LDL. Silencing of VEGF receptor 2 significantly decreased cellular binding, association, and transendothelial transport of (125)I-HDL but not (125)I-LDL. RNA interference with VEGF receptor 1 or VEGF receptor 3 had no effect. Binding, uptake, and transport of HDL but not LDL were strongly reduced in the absence of VEGF-A from the cell culture medium and were restored by the addition of VEGF-A. The restoring effect of VEGF-A on endothelial binding, uptake, and transport of HDL was abrogated by pharmacological inhibition of phosphatidyl-inositol 3 kinase/protein kinase B or p38 mitogen-activated protein kinase, as well as silencing of scavenger receptor BI. Moreover, the presence of VEGF-A was found to be a prerequisite for the localization of scavenger receptor BI in the plasma membrane of endothelial cells. The identification of VEGF as a regulatory factor of transendothelial transport of HDL but not LDL supports the concept that the endothelium is a specific and, hence, druggable barrier for the entry of lipoproteins into the vascular wall. © 2017 American Heart Association, Inc.

  3. Cellular RNA binding proteins NS1-BP and hnRNP K regulate influenza A virus RNA splicing.

    Science.gov (United States)

    Tsai, Pei-Ling; Chiou, Ni-Ting; Kuss, Sharon; García-Sastre, Adolfo; Lynch, Kristen W; Fontoura, Beatriz M A

    2013-01-01

    Influenza A virus is a major human pathogen with a genome comprised of eight single-strand, negative-sense, RNA segments. Two viral RNA segments, NS1 and M, undergo alternative splicing and yield several proteins including NS1, NS2, M1 and M2 proteins. However, the mechanisms or players involved in splicing of these viral RNA segments have not been fully studied. Here, by investigating the interacting partners and function of the cellular protein NS1-binding protein (NS1-BP), we revealed novel players in the splicing of the M1 segment. Using a proteomics approach, we identified a complex of RNA binding proteins containing NS1-BP and heterogeneous nuclear ribonucleoproteins (hnRNPs), among which are hnRNPs involved in host pre-mRNA splicing. We found that low levels of NS1-BP specifically impaired proper alternative splicing of the viral M1 mRNA segment to yield the M2 mRNA without affecting splicing of mRNA3, M4, or the NS mRNA segments. Further biochemical analysis by formaldehyde and UV cross-linking demonstrated that NS1-BP did not interact directly with viral M1 mRNA but its interacting partners, hnRNPs A1, K, L, and M, directly bound M1 mRNA. Among these hnRNPs, we identified hnRNP K as a major mediator of M1 mRNA splicing. The M1 mRNA segment generates the matrix protein M1 and the M2 ion channel, which are essential proteins involved in viral trafficking, release into the cytoplasm, and budding. Thus, reduction of NS1-BP and/or hnRNP K levels altered M2/M1 mRNA and protein ratios, decreasing M2 levels and inhibiting virus replication. Thus, NS1-BP-hnRNPK complex is a key mediator of influenza A virus gene expression.

  4. DRhoGEF2 regulates cellular tension and cell pulsations in the Amnioserosa during Drosophila dorsal closure.

    Directory of Open Access Journals (Sweden)

    Dulce Azevedo

    Full Text Available Coordination of apical constriction in epithelial sheets is a fundamental process during embryogenesis. Here, we show that DRhoGEF2 is a key regulator of apical pulsation and constriction of amnioserosal cells during Drosophila dorsal closure. Amnioserosal cells mutant for DRhoGEF2 exhibit a consistent decrease in amnioserosa pulsations whereas overexpression of DRhoGEF2 in this tissue leads to an increase in the contraction time of pulsations. We probed the physical properties of the amnioserosa to show that the average tension in DRhoGEF2 mutant cells is lower than wild-type and that overexpression of DRhoGEF2 results in a tissue that is more solid-like than wild-type. We also observe that in the DRhoGEF2 overexpressing cells there is a dramatic increase of apical actomyosin coalescence that can contribute to the generation of more contractile forces, leading to amnioserosal cells with smaller apical surface than wild-type. Conversely, in DRhoGEF2 mutants, the apical actomyosin coalescence is impaired. These results identify DRhoGEF2 as an upstream regulator of the actomyosin contractile machinery that drives amnioserosa cells pulsations and apical constriction.

  5. The phosphoinositide 3-kinase signalling pathway in normal and malignant B cells: activation mechanisms, regulation and impact on cellular functions

    Directory of Open Access Journals (Sweden)

    Samantha D Pauls

    2012-08-01

    Full Text Available The phosphoinositide 3-kinase (PI3K pathway is a central signal transduction axis controlling normal B cell homeostasis and activation in humoral immunity. The p110δ PI3K catalytic subunit has emerged as a critical mediator of multiple B cell functions. The activity of this pathway is regulated at multiple levels, with inositol phosphatases PTEN and SHIP both playing critical roles. When deregulated, the PI3K pathway can contribute to B cell malignancies and autoantibody production. This review summarizes current knowledge on key mechanisms that activate and regulate the PI3K pathway and influence normal B cell functional responses including the development of B cell subsets, antigen presentation, immunogloblulin isotype switch, germinal center responses and maintenance of B cell anergy. We also discuss PI3K pathway alterations reported in select B cell malignancies and highlight studies indicating the functional significance of this pathway in malignant B cell survival and growth within tissue microenvironments. Finally, we comment on early clinical trial results, which support PI3K inhibition as a promising treatment of chronic lymphocytic leukemia.

  6. The phosphoinositide 3-kinase signaling pathway in normal and malignant B cells: activation mechanisms, regulation and impact on cellular functions.

    Science.gov (United States)

    Pauls, Samantha D; Lafarge, Sandrine T; Landego, Ivan; Zhang, Tingting; Marshall, Aaron J

    2012-01-01

    The phosphoinositide 3-kinase (PI3K) pathway is a central signal transduction axis controlling normal B cell homeostasis and activation in humoral immunity. The p110δ PI3K catalytic subunit has emerged as a critical mediator of multiple B cell functions. The activity of this pathway is regulated at multiple levels, with inositol phosphatases PTEN and SHIP both playing critical roles. When deregulated, the PI3K pathway can contribute to B cell malignancies and autoantibody production. This review summarizes current knowledge on key mechanisms that activate and regulate the PI3K pathway and influence normal B cell functional responses including the development of B cell subsets, antigen presentation, immunoglobulin isotype switch, germinal center responses, and maintenance of B cell anergy. We also discuss PI3K pathway alterations reported in select B cell malignancies and highlight studies indicating the functional significance of this pathway in malignant B cell survival and growth within tissue microenvironments. Finally, we comment on early clinical trial results, which support PI3K inhibition as a promising treatment of chronic lymphocytic leukemia.

  7. Retinol-binding protein 4 and its membrane receptor STRA6 control adipogenesis by regulating cellular retinoid homeostasis and retinoic acid receptor α activity.

    Science.gov (United States)

    Muenzner, Matthias; Tuvia, Neta; Deutschmann, Claudia; Witte, Nicole; Tolkachov, Alexander; Valai, Atijeh; Henze, Andrea; Sander, Leif E; Raila, Jens; Schupp, Michael

    2013-10-01

    Retinoids are vitamin A (retinol) derivatives and complex regulators of adipogenesis by activating specific nuclear receptors, including the retinoic acid receptor (RAR) and retinoid X receptor (RXR). Circulating retinol-binding protein 4 (RBP4) and its membrane receptor STRA6 coordinate cellular retinol uptake. It is unknown whether retinol levels and the activity of RAR and RXR in adipocyte precursors are linked via RBP4/STRA6. Here, we show that STRA6 is expressed in precursor cells and, dictated by the apo- and holo-RBP4 isoforms, mediates bidirectional retinol transport that controls RARα activity and subsequent adipocyte differentiation. Mobilization of retinoid stores in mice by inducing RBP4 secretion from the liver activated RARα signaling in the precursor cell containing the stromal-vascular fraction of adipose tissue. Retinol-loaded holo-RBP4 blocked adipocyte differentiation of cultured precursors by activating RARα. Remarkably, retinol-free apo-RBP4 triggered retinol efflux that reduced cellular retinoids, RARα activity, and target gene expression and enhanced adipogenesis synergistically with ectopic STRA6. Thus, STRA6 in adipocyte precursor cells links nuclear RARα activity to the circulating RBP4 isoforms, whose ratio in obese mice was shifted toward limiting the adipogenic potential of their precursors. This novel cross talk identifies a retinol-dependent metabolic function of RBP4 that may have important implications for the treatment of obesity.

  8. Transcriptional Regulation of the p53 Tumor Suppressor Gene in S-Phase of the Cell-Cycle and the Cellular Response to DNA Damage

    Directory of Open Access Journals (Sweden)

    David Reisman

    2012-01-01

    Full Text Available The p53 tumor suppressor induces the transcription of genes that negatively regulate progression of the cell cycle in response to DNA damage or other cellular stressors and thus participates in maintaining genome stability. Numerous studies have demonstrated that p53 transcription is activated before or during early S-phase in cells progressing from G0/G1 into S-phase through the combined action of two DNA-binding factors RBP-Jκ and C/EBPβ-2. Here, we review evidence that this induction occurs to provide available p53 mRNA in order to prepare the cell for DNA damage in S-phase, this ensuring a rapid response to DNA damage before exiting this stage of the cell cycle.

  9. ANK1 is up-regulated in laser captured microglia in Alzheimer’s brain; the importance of addressing cellular heterogeneity

    Science.gov (United States)

    Sekar, Shobana; Nolz, Jennifer; Delvaux, Elaine; Lunnon, Katie; Mill, Jonathan; Liang, Winnie S.; Coleman, Paul D.

    2017-01-01

    Recent epigenetic association studies have identified a new gene, ANK1, in the pathogenesis of Alzheimer’s disease (AD). Although strong associations were observed, brain homogenates were used to generate the data, introducing complications because of the range of cell types analyzed. In order to address the issue of cellular heterogeneity in homogenate samples we isolated microglial, astrocytes and neurons by laser capture microdissection from CA1 of hippocampus in the same individuals with a clinical and pathological diagnosis of AD and matched control cases. Using this unique RNAseq data set, we show that in the hippocampus, ANK1 is significantly (p<0.0001) up-regulated 4-fold in AD microglia, but not in neurons or astrocytes from the same individuals. These data provide evidence that microglia are the source of ANK1 differential expression previously identified in homogenate samples in AD. PMID:28700589

  10. De-regulation of gene expression and alternative splicing affects distinct cellular pathways in the aging hippocampus

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    Roman M Stilling

    2014-11-01

    Full Text Available Aging is accompanied by gradually increasing impairment of cognitive abilities and constitutes the main risk factor of neurodegenerative conditions like Alzheimer’s disease. The underlying mechanisms are however not well understood. Here we analyze the hippocampal transcriptome of young adult mice and two groups of mice at advanced age using RNA sequencing. This approach enabled us to test differential expression of coding and non-coding transcripts, as well as differential splicing and RNA editing. We report a specific age-associated gene expression signature that is associated with major genetic risk factors for late-onset Alzheimer’s disease. This signature is dominated by neuroinflammatory processes, specifically activation of the complement system at the level of increased gene expression, while de-regulation of neuronal plasticity appears to be mediated by compromised RNA splicing.

  11. Up-regulation of leucocytes genes implicated in telomere dysfunction and cellular senescence correlates with depression and anxiety severity scores.

    Directory of Open Access Journals (Sweden)

    Jean-Raymond Teyssier

    Full Text Available BACKGROUND: Major depressive disorder (MDD is frequently associated with chronic medical illness responsible of increased disability and mortality. Inflammation and oxidative stress are considered to be the major mediators of the allostatic load, and has been shown to correlate with telomere erosion in the leucocytes of MDD patients, leading to the model of accelerated aging. However, the significance of telomere length as an exclusive biomarker of aging has been questioned on both methodological and biological grounds. Furthermore, telomeres significantly shorten only in patients with long lasting MDD. Sensitive and dynamic functional biomarkers of aging would be clinically useful to evaluate the somatic impact of MDD. METHODOLOGY: To address this issue we have measured in the blood leucocytes of MDD patients (N=17 and controls (N=16 the expression of two genes identified as robust biomarkers of human aging and telomere dysfunction: p16(INK4a and STMN1. We have also quantified the transcripts of genes involved in the repair of oxidative DNA damage at telomeres (OGG1, telomere regulation and elongation (TERT, and in the response to biopsychological stress (FOS and DUSP1. RESULTS: The OGG1, p16(INK4a, and STMN1 gene were significantly up-regulated (25 to 100% in the leucocytes of MDD patients. Expression of p16(INK4a and STMN1 was directly correlated with anxiety scores in the depression group, and that of p16(INK4a, STMN and TERT with the depression and anxiety scores in the combined sample (MDD plus controls. Furthermore, we identified a unique correlative pattern of gene expression in the leucocytes of MDD subjects. CONCLUSIONS: Expression of p16(INK4 and STMN1 is a promising biomarker for future epidemiological assessment of the somatic impact of depressive and anxious symptoms, at both clinical and subclinical level in both depressive patients and general population.

  12. Protein kinase CK2 localizes to sites of DNA double-strand break regulating the cellular response to DNA damage

    Directory of Open Access Journals (Sweden)

    Olsen Birgitte B

    2012-03-01

    Full Text Available Abstract Background The DNA-dependent protein kinase (DNA-PK is a nuclear complex composed of a large catalytic subunit (DNA-PKcs and a heterodimeric DNA-targeting subunit Ku. DNA-PK is a major component of the non-homologous end-joining (NHEJ repair mechanism, which is activated in the presence of DNA double-strand breaks induced by ionizing radiation, reactive oxygen species and radiomimetic drugs. We have recently reported that down-regulation of protein kinase CK2 by siRNA interference results in enhanced cell death specifically in DNA-PKcs-proficient human glioblastoma cells, and this event is accompanied by decreased autophosphorylation of DNA-PKcs at S2056 and delayed repair of DNA double-strand breaks. Results In the present study, we show that CK2 co-localizes with phosphorylated histone H2AX to sites of DNA damage and while CK2 gene knockdown is associated with delayed DNA damage repair, its overexpression accelerates this process. We report for the first time evidence that lack of CK2 destabilizes the interaction of DNA-PKcs with DNA and with Ku80 at sites of genetic lesions. Furthermore, we show that CK2 regulates the phosphorylation levels of DNA-PKcs only in response to direct induction of DNA double-strand breaks. Conclusions Taken together, these results strongly indicate that CK2 plays a prominent role in NHEJ by facilitating and/or stabilizing the binding of DNA-PKcs and, possibly other repair proteins, to the DNA ends contributing to efficient DNA damage repair in mammalian cells.

  13. Humoral and cellular immune responses to glucose regulated protein 78 - a novel Leishmania donovani antigen

    DEFF Research Database (Denmark)

    Jensen, Anja T R; Ismail, Ahmed; Gaafar, Ameera

    2002-01-01

    evaluation of plasma samples obtained in Sudan revealed that 89% of patients with visceral leishmaniasis (VL), 78% with post kala-azar dermal leishmaniasis (PKDL), and 85% with cutaneous leishmaniasis (CL) had antibody reactivity to this Leishmania antigen. Plasma from healthy Sudanese individuals living...... in an area endemic for malaria but free of leishmaniasis and plasma from healthy Danes was negative in the assay. GRP78 antibody was detected in 10% and 5% of plasma samples from Sudanese and Ghanaian malaria patients, respectively, whereas 35% of plasma samples from otherwise healthy Sudanese individuals...

  14. Campylobacter jejuni CsrA complements an Escherichia coli csrA mutation for the regulation of biofilm formation, motility and cellular morphology but not glycogen accumulation

    Directory of Open Access Journals (Sweden)

    Fields Joshua A

    2012-10-01

    Full Text Available Abstract Background Although Campylobacter jejuni is consistently ranked as one of the leading causes of bacterial diarrhea worldwide, the mechanisms by which C. jejuni causes disease and how they are regulated have yet to be clearly defined. The global regulator, CsrA, has been well characterized in several bacterial genera and is known to regulate a number of independent pathways via a post transcriptional mechanism, but remains relatively uncharacterized in the genus Campylobacter. Previously, we reported data illustrating the requirement for CsrA in several virulence related phenotypes of C. jejuni strain 81–176, indicating that the Csr pathway is important for Campylobacter pathogenesis. Results We compared the Escherichia coli and C. jejuni orthologs of CsrA and characterized the ability of the C. jejuni CsrA protein to functionally complement an E. coli csrA mutant. Phylogenetic comparison of E. coli CsrA to orthologs from several pathogenic bacteria demonstrated variability in C. jejuni CsrA relative to the known RNA binding domains of E. coli CsrA and in several amino acids reported to be involved in E. coli CsrA-mediated gene regulation. When expressed in an E. coli csrA mutant, C. jejuni CsrA succeeded in recovering defects in motility, biofilm formation, and cellular morphology; however, it failed to return excess glycogen accumulation to wild type levels. Conclusions These findings suggest that C. jejuni CsrA is capable of efficiently binding some E. coli CsrA binding sites, but not others, and provide insight into the biochemistry of C. jejuni CsrA.

  15. Steroidogenesis and early response gene expression in MA-10 Leydig tumor cells following heterologous receptor down-regulation and cellular desensitization

    Directory of Open Access Journals (Sweden)

    Tsuey-Ming Chen

    2016-03-01

    Full Text Available The Leydig tumor cell line, MA-10, expresses the luteinizing hormone receptor, a G protein-coupled receptor that, when activated with luteinizing hormone or chorionic gonadotropin (CG, stimulates cAMP production and subsequent steroidogenesis, notably progesterone. These cells also respond to epidermal growth factor (EGF and phorbol esters with increased steroid biosynthesis. In order to probe the intracellular pathways along with heterologous receptor down-regulation and cellular desensitization, cells were preincubated with EGF or phorbol esters and then challenged with CG, EGF, dibutryl-cyclic AMP, and a phorbol ester. Relative receptor numbers, steroid biosynthesis, and expression of the early response genes, JUNB and c-FOS, were measured. It was found that in all cases but one receptor down-regulation and decreased progesterone production were closely coupled under the conditions used; the exception involved preincubation of the cells with EGF followed by addition of CG where the CG-mediated stimulation of steroidogenesis was considerably lower than the level of receptor down-regulation. In a number of instances JUNB and c-FOS expression paralleled the decreases in receptor number and progesterone production, while in some cases these early response genes were affected little if at all by the changes in receptor number. This finding may indicate that even low levels of activated signaling kinases, e.g. protein kinase A, protein kinase C, or receptor tyrosine kinase, may suffice to yield good expression of JUNB and c-FOS, or it may suggest alternative pathways for regulating expression of these two early response genes.

  16. Structure-guided mutational analysis of gene regulation by the Bacillus subtilis pbuE adenine-responsive riboswitch in a cellular context.

    Science.gov (United States)

    Marcano-Velázquez, Joan G; Batey, Robert T

    2015-02-13

    Riboswitches are a broadly distributed form of RNA-based gene regulation in Bacteria and, more rarely, Archaea and Eukarya. Most often found in the 5'-leader sequence of bacterial mRNAs, they are generally composed of two functional domains: a receptor (aptamer) domain that binds an effector molecule and a regulatory domain (or expression platform) that instructs the expression machinery. One of the most studied riboswitches is the Bacillus subtilis adenine-responsive pbuE riboswitch, which regulates gene expression at the transcriptional level, up-regulating expression in response to increased intracellular effector concentrations. In this work, we analyzed sequence and structural elements that contribute to efficient ligand-dependent regulatory activity in a co-transcriptional and cellular context. Unexpectedly, we found that the P1 helix, which acts as the antitermination element of the switch in this RNA, supported ligand-dependent activation of a reporter gene over a broad spectrum of lengths from 3 to 10 bp. This same trend was also observed using a minimal in vitro single-turnover transcription assay, revealing that this behavior is intrinsic to the RNA sequence. We also found that the sequences at the distal tip of the terminator not directly involved in alternative secondary structure formation are highly important for efficient regulation. These data strongly support a model in which the switch is highly localized to the P1 helix adjacent to the ligand-binding pocket that likely presents a local kinetic block to invasion of the aptamer by the terminator.

  17. The collagen triple helix repeat containing 1 facilitates hepatitis B virus-associated hepatocellular carcinoma progression by regulating multiple cellular factors and signal cascades.

    Science.gov (United States)

    Zhang, Rui; Cao, Yanhua; Bai, Lan; Zhu, Chengliang; Li, Rui; He, Hui; Liu, Yingle; Wu, Kailang; Liu, Fang; Wu, Jianguo

    2015-12-01

    Hepatitis B virus (HBV) infection is one of the major causes of acute and chronic liver diseases, fulminant hepatitis, cirrhosis, and hepatocellular carcinoma (HCC). HCC accounts for more than 85% of primary liver cancers and is the seventh most common cancer and the third leading cause of cancer-related deaths. However, the mechanism by which HBV induces HCC is largely unknown. Collagen triple helixes repeat containing 1 (CTHRC1) is a secreted protein and has characteristics of a circulating hormone with potentially broad implications for cell metabolism and physiology. CTHRC1 is associated with human cancers, but its effect on HCC is unknown. Here, we revealed that CTHRC1 expression is highly correlated with HCC progression in HBV-infected patients, and demonstrated that HBV stimulates CTHRC1 expression by activating nuclear factor-kappa B (NF-κB) and cAMP response element binding protein (CREB), through extracellular signal-regulated kinase/c-Jun N-terminal kinase (ERK/c-JNK) pathway. In addition, CTHRC1 activates hypoxia-inducible factor 1α (HIF-1α) and vascular endothelial growth factor (VEGF) through regulating phosphoinosmde-3-kinase/protein kinase B/mammalian target of rapamycin (PI-3K/AKT/mTOR) pathway. More interestingly, CTHRC1 enhances colony formation, migration, and invasion of hepatoma cells by regulating p53 and stimulating matrix metalloproteinase-9 (MMP-9) expression. In addition, knock-down of CTHRC1 results in the repression of HBV-associated carcinogenesis in nude mice. Thus, we revealed a novel mechanism by which HBV facilitates HCC development through activating the oncoprotein CTHRC1, which in turn enhances HBV-related HCC progression by stimulates colony formation, migration, and invasion of hepatoma cells through regulating multiple cellular factors and signal cascades.

  18. Expression, cellular localization, and involvement of the pentose phosphate pathway enzymes in the regulation of ram sperm capacitation.

    Science.gov (United States)

    Luna, C; Serrano, E; Domingo, J; Casao, A; Pérez-Pé, R; Cebrián-Pérez, J A; Muiño-Blanco, T

    2016-08-01

    Spermatozoa require substantially more ATP than other cells, not only for sustaining sperm motility but also for regulating protein phosphorylation during capacitation. In this study, we have reported for the first time the presence of the two key enzymes of the pentose phosphate pathway (PPP), glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase in ovine spermatozoa by indirect immunofluorescence, Western blotting, in-gel activity, and reverse transcription polymerase chain reaction analysis. We found that the activity of both enzymes significantly increased after in vitro capacitation in the presence of high-cAMP levels, with a concomitant increase in protein tyrosine phosphorylation and in the proportion of sperm-capacitated pattern assessed by the chlortetracycline staining. These results suggest that PPP is related with the progress of capacitation and that a relationship between calcium compartmentalization, protein tyrosine phosphorylation and PPP seems to exist. This is the first report that shows a connection between the PPP, cAMP/PKA signaling pathways and sperm capacitation. These findings can be of high-biological importance to improve our knowledge of the biochemical mechanisms involved in the acquisition of mammalian sperm functional competence and, ultimately, fertility.

  19. Regulation of the hypertonic stress response and other cellular functions by the Rel-like transcription factor NFAT5.

    Science.gov (United States)

    Aramburu, José; Drews-Elger, Katherine; Estrada-Gelonch, Anaïs; Minguillón, Jordi; Morancho, Beatriz; Santiago, Verónica; López-Rodríguez, Cristina

    2006-11-30

    Stress, be it from environmental factors or intrinsic to the cell as result of growth and metabolism, can be harmful to cells. Mammalian cells have developed numerous mechanisms to respond to diverse forms of stress. These mechanisms combine signaling cascades and activation of gene expression programs to orchestrate an adaptive response that will allow the cell to survive and resume its normal functioning. In this review we will focus on the transcription factor NFAT5, a fundamental regulator of the response to osmotic stress in mammalian cells. Identified in 1999, NFAT5 is the latest addition to the Rel family, which comprises the NF-kappaB and NFATc proteins. Though in some of its structural and functional features NFAT5 is a hybrid between these two major groups of Rel proteins, it has unique characteristics that make it stand on its own as a third type of Rel transcription factor. Since its discovery, NFAT5 has been studied mostly in the context of the hypertonicity stress response. The advent of mouse models deficient in NFAT5 and other recent advances have confirmed a fundamental osmoprotective role for this factor in mammals, but also revealed features that suggest it may have a wider range of functions.

  20. Cellular automata

    CERN Document Server

    Codd, E F

    1968-01-01

    Cellular Automata presents the fundamental principles of homogeneous cellular systems. This book discusses the possibility of biochemical computers with self-reproducing capability.Organized into eight chapters, this book begins with an overview of some theorems dealing with conditions under which universal computation and construction can be exhibited in cellular spaces. This text then presents a design for a machine embedded in a cellular space or a machine that can compute all computable functions and construct a replica of itself in any accessible and sufficiently large region of t

  1. Cellular zinc is required for intestinal epithelial barrier maintenance via the regulation of claudin-3 and occludin expression.

    Science.gov (United States)

    Miyoshi, Yuka; Tanabe, Soichi; Suzuki, Takuya

    2016-07-01

    Intracellular zinc is required for a variety of cell functions, but its precise roles in the maintenance of the intestinal tight junction (TJ) barrier remain unclear. The present study investigated the essential roles of intracellular zinc in the preservation of intestinal TJ integrity and the underlying molecular mechanisms. Depletion of intracellular zinc in both intestinal Caco-2 cells and mouse colons through the application of a cell-permeable zinc chelator N,N,N',N'-tetrakis(2-pyridylmethyl)ethylenediamine (TPEN) induced a disruption of the TJ barrier, as indicated by increased FITC-labeled dextran flux and decreased transepithelial electrical resistance. The TPEN-induced TJ disruption is associated with downregulation of two TJ proteins, occludin and claudin-3. Biotinylation of cell surface proteins revealed that the zinc depletion induced the proteolysis of occludin but not claudin-3. Occludin proteolysis was sensitive to the inhibition of calpain activity, and increased calpain activity was observed in the zinc-depleted cells. Although quantitative PCR analysis and promoter reporter assay have demonstrated that the zinc depletion-induced claudin-3 downregulation occurred at transcriptional levels, a site-directed mutation in the egr1 binding site in the claudin-3 promoter sequence induced loss of both the basal promoter activity and the TPEN-induced decreases. Reduced egr1 expression by a specific siRNA also inhibited claudin-3 expression and transepithelial electrical resistance maintenance in cells. This study shows that intracellular zinc has an essential role in the maintenance of the intestinal epithelial TJ barrier through regulation of occludin proteolysis and claudin-3 transcription.

  2. 76 FR 61266 - Special Regulations; Areas of the National Park System, Grand Teton National Park, Bicycle Routes...

    Science.gov (United States)

    2011-10-04

    ..., Grand Teton National Park, Bicycle Routes, Fishing and Vessels AGENCY: National Park Service, Interior... (Park) as routes for bicycle use. National Park Service (NPS) regulations require issuance of a special regulation to designate bicycle routes that are located off park roads and outside developed areas. The...

  3. LiZIP3 is a cellular zinc transporter that mediates the tightly regulated import of zinc in Leishmania infantum parasites

    Science.gov (United States)

    Carvalho, Sandra; da Silva, Rosa Barreira; Shawki, Ali; Castro, Helena; Lamy, Márcia; Eide, David; Costa, Vítor; Mackenzie, Bryan; Tomás, Ana M.

    2016-01-01

    Summary Cellular zinc homeostasis ensures that the intracellular concentration of this element is kept within limits that enable its participation in critical physiological processes without exerting toxic effects. We report here the identification and characterization of the first mediator of zinc homeostasis in Leishmania infantum, LiZIP3, a member of the ZIP family of divalent metal-ion transporters. The zinc transporter activity of LiZIP3 was first disclosed by its capacity to rescue the growth of Saccharomyces cerevisiae strains deficient in zinc acquisition. Subsequent expression of LiZIP3 in Xenopus laevis oocytes was shown to stimulate the uptake of a broad range of metal ions, among which Zn2+ was the preferred LiZIP3 substrate (K0.5 ≈ 0.1 μM). Evidence that LiZIP3 functions as a zinc importer in L. infantum came from the observations that the protein locates to the cell membrane and that its overexpression leads to augmented zinc internalization. Importantly, expression and cell-surface location of LiZIP3 are lost when parasites face high zinc bioavailability. LiZIP3 decline in response to zinc is regulated at the mRNA level in a process involving (a) short-lived protein(s). Collectively, our data reveal that LiZIP3 enables L. infantum to acquire zinc in a highly regulated manner, hence contributing to zinc homeostasis. PMID:25644708

  4. A proteomic screen with Drosophila Opa1-like identifies Hsc70-5/Mortalin as a regulator of mitochondrial morphology and cellular homeostasis.

    Science.gov (United States)

    Banerjee, Shamik; Chinthapalli, Balaji

    2014-09-01

    Mitochondrial morphology is regulated by conserved proteins involved in fusion and fission processes. The mammalian Optic atrophy 1 (OPA1) that functions in mitochondrial fusion is associated with Optic Atrophy and has been implicated in inner membrane cristae remodeling during cell death. Here, we show Drosophila Optic atrophy 1-like (Opa1-like) influences mitochondrial morphology through interaction with 'mitochondria-shaping' proteins like Mitochondrial assembly regulatory factor (Marf) and Drosophila Mitofilin (dMitofilin). To gain an insight into Opa1-like's network, we delineated bonafide interactors like dMitofilin, Marf, Serine protease High temperature requirement protein A2 (HTRA2), Rhomboid-7 (Rho-7) along with novel interactors such as Mortalin ortholog (Hsc70-5) from Drosophila mitochondrial extract. Interestingly, RNAi mediated down-regulation of hsc70-5 in Drosophila wing imaginal disc's peripodial cells resulted in fragmented mitochondria with reduced membrane potential leading to proteolysis of Opa1-like. Increased ecdysone activity induced dysfunctional fragmented mitochondria for clearance through lysosomes, an effect enhanced in hsc70-5 RNAi leading to increased cell death. Over-expression of Opa1-like rescues mitochondrial morphology and cell death in prepupal tissues expressing hsc70-5 RNAi. Taken together, we have identified a novel interaction between Hsc70-5/Mortalin and Opa1-like that influences cellular homeostasis through mitochondrial fusion.

  5. The Rab GTPase Rab8 as a shared regulator of ciliogenesis and immune synapse assembly: From a conserved pathway to diverse cellular structures

    Science.gov (United States)

    Patrussi, Laura; Baldari, Cosima T.

    2016-01-01

    ABSTRACT Rab GTPases, which form the largest branch of the Ras GTPase superfamily, regulate almost every step of vesicle-mediated trafficking. Among them, Rab8 is an essential participant in primary cilium formation. In a report recently published in the Journal of Cell Science, Finetti and colleagues identify Rab8 as a novel player in vesicular traffic in the non-ciliated T lymphocytes, which contributes to the assembly of the specialized signaling platform known as the immune synapse. By interacting with the v-SNARE VAMP-3, Rab8 is indeed responsible for the final docking/fusion step in T cell receptor (TCR) recycling to the immune synapse. A second important take-home message which comes to light from this work is that VAMP-3 also interacts with Rab8 at the base of the cilium in NIH-3T3 cells, where it regulates ciliary growth and targeting of Smoothened at the plasma membrane. Hence the data presented in this report, in addition to identifying Rab8 as a novel player in vesicular traffic to the immune synapse, reveal how both ciliated and non-ciliated cells take advantage of a conserved pathway to build highly specific cellular structures. PMID:26587735

  6. Design of cryptographically secure AES like S-Box using second-order reversible cellular automata for wireless body area network applications.

    Science.gov (United States)

    Gangadari, Bhoopal Rao; Rafi Ahamed, Shaik

    2016-09-01

    In biomedical, data security is the most expensive resource for wireless body area network applications. Cryptographic algorithms are used in order to protect the information against unauthorised access. Advanced encryption standard (AES) cryptographic algorithm plays a vital role in telemedicine applications. The authors propose a novel approach for design of substitution bytes (S-Box) using second-order reversible one-dimensional cellular automata (RCA(2)) as a replacement to the classical look-up-table (LUT) based S-Box used in AES algorithm. The performance of proposed RCA(2) based S-Box and conventional LUT based S-Box is evaluated in terms of security using the cryptographic properties such as the nonlinearity, correlation immunity bias, strict avalanche criteria and entropy. Moreover, it is also shown that RCA(2) based S-Boxes are dynamic in nature, invertible and provide high level of security. Further, it is also found that the RCA(2) based S-Box have comparatively better performance than that of conventional LUT based S-Box.

  7. Solving a mathematical model integrating unequal-area facilities layout and part scheduling in a cellular manufacturing system by a genetic algorithm.

    Science.gov (United States)

    Ebrahimi, Ahmad; Kia, Reza; Komijan, Alireza Rashidi

    2016-01-01

    In this article, a novel integrated mixed-integer nonlinear programming model is presented for designing a cellular manufacturing system (CMS) considering machine layout and part scheduling problems simultaneously as interrelated decisions. The integrated CMS model is formulated to incorporate several design features including part due date, material handling time, operation sequence, processing time, an intra-cell layout of unequal-area facilities, and part scheduling. The objective function is to minimize makespan, tardiness penalties, and material handling costs of inter-cell and intra-cell movements. Two numerical examples are solved by the Lingo software to illustrate the results obtained by the incorporated features. In order to assess the effects and importance of integration of machine layout and part scheduling in designing a CMS, two approaches, sequentially and concurrent are investigated and the improvement resulted from a concurrent approach is revealed. Also, due to the NP-hardness of the integrated model, an efficient genetic algorithm is designed. As a consequence, computational results of this study indicate that the best solutions found by GA are better than the solutions found by B&B in much less time for both sequential and concurrent approaches. Moreover, the comparisons between the objective function values (OFVs) obtained by sequential and concurrent approaches demonstrate that the OFV improvement is averagely around 17 % by GA and 14 % by B&B.

  8. The potential benefits of herbicide regulation: a cautionary note for the Great Barrier Reef catchment area.

    Science.gov (United States)

    Davis, A M; Lewis, S E; Brodie, J E; Benson, Ash

    2014-08-15

    Industry transitions away from traditional photosystem II inhibiting (PSII) herbicides towards an 'alternative' herbicide suite are now widely advocated as a key component of improved environmental outcomes for Australia's Great Barrier Reef and improved environmental stewardship on the part of the Queensland sugar industry. A systematic desktop risk analysis found that based on current farming practices, traditional PSII herbicides can pose significant environmental risks. Several of the 'alternatives' that can directly fill a specific pre-emergent ('soil residual') weed control function similar to regulated PSII herbicides also, however, presented a similar environmental risk profile, regardless of farming systems and bio-climatic zones being considered. Several alternatives with a pre-emergent residual function as well as alternative post-emergent (contact or 'knockdown') herbicides were, predicted to pose lower environmental risks than the regulated PSII herbicides to most trophic levels, although environmental risks could still be present. While several herbicides may well be viable alternatives in terms of weed control, they can still present equal or possibly higher risks to the environment. Imposing additional regulations (or even de-registrations) on particular herbicides could result in marginal, and possibly perverse environmental impacts in the long term, if usage shifts to alternative herbicides with similar risk profiles. Regardless of any regulatory efforts, improved environmental sustainability outcomes in pesticide practices within the Great Barrier Reef catchment area will hinge primarily on the continuing adoption of integrated, strategic pest management systems and technologies applied to both traditional and 'alternative' herbicides. One of the emerging policy challenges is ensuring the requisite technical and extension support for cane growers to ensure effective adoption of rapidly evolving farming system technologies, in a very dynamic and

  9. Processing the Bouguer anomaly map of Biga and the surrounding area by the cellular neural network: application to the southwestern Marmara region

    Science.gov (United States)

    Aydogan, D.

    2007-04-01

    An image processing technique called the cellular neural network (CNN) approach is used in this study to locate geological features giving rise to gravity anomalies such as faults or the boundary of two geologic zones. CNN is a stochastic image processing technique based on template optimization using the neighborhood relationships of cells. These cells can be characterized by a functional block diagram that is typical of neural network theory. The functionality of CNN is described in its entirety by a number of small matrices (A, B and I) called the cloning template. CNN can also be considered to be a nonlinear convolution of these matrices. This template describes the strength of the nearest neighbor interconnections in the network. The recurrent perceptron learning algorithm (RPLA) is used in optimization of cloning template. The CNN and standard Canny algorithms were first tested on two sets of synthetic gravity data with the aim of checking the reliability of the proposed approach. The CNN method was compared with classical derivative techniques by applying the cross-correlation method (CC) to the same anomaly map as this latter approach can detect some features that are difficult to identify on the Bouguer anomaly maps. This approach was then applied to the Bouguer anomaly map of Biga and its surrounding area, in Turkey. Structural features in the area between Bandirma, Biga, Yenice and Gonen in the southwest Marmara region are investigated by applying the CNN and CC to the Bouguer anomaly map. Faults identified by these algorithms are generally in accordance with previously mapped surface faults. These examples show that the geologic boundaries can be detected from Bouguer anomaly maps using the cloning template approach. A visual evaluation of the outputs of the CNN and CC approaches is carried out, and the results are compared with each other. This approach provides quantitative solutions based on just a few assumptions, which makes the method more

  10. Retina-specific nuclear receptor: A potential regulator of cellular retinaldehyde-binding protein expressed in retinal pigment epithelium and Müller glial cells.

    Science.gov (United States)

    Chen, F; Figueroa, D J; Marmorstein, A D; Zhang, Q; Petrukhin, K; Caskey, C T; Austin, C P

    1999-12-21

    In an effort to identify nuclear receptors important in retinal disease, we screened a retina cDNA library for nuclear receptors. Here we describe the identification of a retina-specific nuclear receptor (RNR) from both human and mouse. Human RNR is a splice variant of the recently published photoreceptor cell-specific nuclear receptor [Kobayashi, M., Takezawa, S., Hara, K., Yu, R. T., Umesono, Y., Agata, K., Taniwaki, M., Yasuda, K. & Umesono, K. (1999) Proc. Natl. Acad. Sci. USA 96, 4814-4819] whereas the mouse RNR is a mouse ortholog. Northern blot and reverse transcription-PCR analyses of human mRNA samples demonstrate that RNR is expressed exclusively in the retina, with transcripts of approximately 7.5 kb, approximately 3.0 kb, and approximately 2.3 kb by Northern blot analysis. In situ hybridization with multiple probes on both primate and mouse eye sections demonstrates that RNR is expressed in the retinal pigment epithelium and in Müller glial cells. By using the Gal4 chimeric receptor/reporter cotransfection system, the ligand binding domain of RNR was found to repress transcriptional activity in the absence of exogenous ligand. Gel mobility shift assays revealed that RNR can interact with the promoter of the cellular retinaldehyde binding protein gene in the presence of retinoic acid receptor (RAR) and/or retinoid X receptor (RXR). These data raise the possibility that RNR acts to regulate the visual cycle through its interaction with cellular retinaldehyde binding protein and therefore may be a target for retinal diseases such as retinitis pigmentosa and age-related macular degeneration.

  11. 78 FR 59231 - Regulated Navigation Area-Tappan Zee Bridge Construction Project, Hudson River; South Nyack and...

    Science.gov (United States)

    2013-09-26

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA11 Regulated Navigation Area--Tappan Zee Bridge... area (RNA) on the navigable waters of the Hudson River surrounding the Tappan Zee Bridge. This... situation created by the construction of the Tappan Zee Bridge. The Coast Guard has discussed this...

  12. 77 FR 67563 - Regulated Navigation Area-New Haven Harbor, Quinnipiac River, Mill River, New Haven, CT; Pearl...

    Science.gov (United States)

    2012-11-13

    ... River, Mill River, New Haven, CT; Pearl Harbor Memorial Bridge (Interstate 95) Construction AGENCY... area which will be needed during construction of the new Pearl Harbor Memorial Bridge, and which could...) entitled Regulated Navigation Area--New Haven Harbor, Quinnipiac River, Mill River, New Haven, CT;...

  13. 75 FR 17034 - Irish Potatoes Grown in Colorado; Relaxation of the Handling Regulation for Area No. 3

    Science.gov (United States)

    2010-04-05

    ... Agricultural Marketing Service 7 CFR Part 948 Irish Potatoes Grown in Colorado; Relaxation of the Handling... grown in Areas No. 2 and No. 3 only; regulation for Area No. 1 is currently not active. Grade, size, and... while satisfying consumer demand for smaller potatoes. This size relaxation is also expected to increase...

  14. Expression of human papilloma virus type 16 E5 protein in amelanotic melanoma cells regulates endo-cellular pH and restores tyrosinase activity

    Directory of Open Access Journals (Sweden)

    Coccia Raffaella

    2009-01-01

    Full Text Available Abstract Background Melanin synthesis, the elective trait of melanocytes, is regulated by tyrosinase activity. In tyrosinase-positive amelanotic melanomas this rate limiting enzyme is inactive because of acidic endo-melanosomal pH. The E5 oncogene of the Human Papillomavirus Type 16 is a small transmembrane protein with a weak transforming activity and a role during the early steps of viral infections. E5 has been shown to interact with 16 kDa subunit C of the trans-membrane Vacuolar ATPase proton pump ultimately resulting in its functional suppressions. However, the cellular effects of such an interaction are still under debate. With this work we intended to explore whether the HPV16 E5 oncoprotein does indeed interact with the vacuolar ATPase proton pump once expressed in intact human cells and whether this interaction has functional consequences on cell metabolism and phenotype. Methods The expression of the HPV16-E5 oncoproteins was induced in two Tyrosinase-positive amelanotic melanomas (the cell lines FRM and M14 by a retroviral expression construct. Modulation of the intracellular pH was measured with Acridine orange and fluorescence microscopy. Expression of tyrosinase and its activity was followed by RT-PCR, Western Blot and enzyme assay. The anchorage-independence growth and the metabolic activity of E5 expressing cells were also monitored. Results We provide evidence that in the E5 expressing cells interaction between E5 and V-ATPase determines an increase of endo-cellular pH. The cellular alkalinisation in turn leads to the post-translational activation of tyrosinase, melanin synthesis and phenotype modulation. These effects are associated with an increased activation of tyrosine analogue anti-blastic drugs. Conclusion Once expressed within intact human cells the HPV16-E5 oncoprotein does actually interact with the vacuolar V-ATPase proton pump and this interaction induces a number of functional effects. In amelanotic melanomas these

  15. 33 CFR 165.923 - Regulated Navigation Area between mile markers 296.1 and 296.7 of the Chicago Sanitary and Ship...

    Science.gov (United States)

    2010-07-01

    ... (CONTINUED) PORTS AND WATERWAYS SAFETY REGULATED NAVIGATION AREAS AND LIMITED ACCESS AREAS Specific Regulated... regulated navigation area must be made up with wire rope to ensure electrical connectivity between all... Port, Lake Michigan is a designated representative of the District Commander for the purposes of...

  16. Regulation of formal and informal water service providers in peri-urban areas of Maputo, Mozambique

    Science.gov (United States)

    Matsinhe, Nelson P.; Juízo, Dinis; Macheve, Berta; Santos, Clara dos

    Service delivery to large areas of peri-urban Maputo depends largely on alternative informal service providers. These providers are located within the limits of Maputo, in a water supply area that is formally leased to a private operator. Informal service providers therefore operate within the main regulatory body, but their activity is presently unregulated. This paper discusses activities of informal alternative providers in peri-urban areas of Maputo, Mozambique, and opportunities to expand the reach and influence of the main regulatory body to this segment of service providers. The study was commissioned to assist the main regulatory body to setup a strategy to improve the pro-poor focus of the existing regulatory environment and so improve access to potable water for the majority of the under-serviced urban poor. Results of field surveys conducted in selected areas of peri-urban Maputo are presented. The surveys focused on the quality of services, the legal status of independent providers and the organization of water supply services at neighbourhood level. The results indicate that household water resellers and small-scale independent provides are presently an important and indispensable source of access to water for the majority of unconnected residents in peri-urban Maputo and that they are reported to cater for as many as 21% of unconnected households of such neighbourhoods. In the near future, alternative providers will continue to have a dominant role in service delivery in peri-urban Maputo, therefore their legalization and decentralization of certain regulatory functions to the neighbourhood level is required. A neighbourhood based management model is proposed for that purpose. The model is based on a standpipe management model that is broadened to include alternative service providers. The model addresses issues such as water pricing, bidding and compliance strategies, channels for consumer’s representation and possibilities of creating

  17. Neurobiological mechanisms for the regulation of mammalian sleep-wake behavior: reinterpretation of historical evidence and inclusion of contemporary cellular and molecular evidence.

    Science.gov (United States)

    Datta, Subimal; Maclean, Robert Ross

    2007-01-01

    At its most basic level, the function of mammalian sleep can be described as a restorative process of the brain and body; recently, however, progressive research has revealed a host of vital functions to which sleep is essential. Although many excellent reviews on sleep behavior have been published, none have incorporated contemporary studies examining the molecular mechanisms that govern the various stages of sleep. Utilizing a holistic approach, this review is focused on the basic mechanisms involved in the transition from wakefulness, initiation of sleep and the subsequent generation of slow-wave sleep and rapid eye movement (REM) sleep. Additionally, using recent molecular studies and experimental evidence that provides a direct link to sleep as a behavior, we have developed a new model, the cellular-molecular-network model, explaining the mechanisms responsible for regulating REM sleep. By analyzing the fundamental neurobiological mechanisms responsible for the generation and maintenance of sleep-wake behavior in mammals, we intend to provide a broader understanding of our present knowledge in the field of sleep research.

  18. Syndecan-1 Acts as an Important Regulator of CXCL1 Expression and Cellular Interaction of Human Endometrial Stromal and Trophoblast Cells

    Directory of Open Access Journals (Sweden)

    Dunja Maria Baston-Buest

    2017-01-01

    Full Text Available Successful implantation of the embryo into the human receptive endometrium is substantial for the establishment of a healthy pregnancy. This study focusses on the role of Syndecan-1 at the embryo-maternal interface, the multitasking coreceptor influencing ligand concentration, release and receptor presentation, and cellular morphology. CXC motif ligand 1, being involved in chemotaxis and angiogenesis during implantation, is of special interest as a ligand of Syndecan-1. Human endometrial stromal cells with and without Syndecan-1 knock-down were decidualized and treated with specific inhibitors to evaluate signaling pathways regulating CXC ligand 1 expression. Western blot analyses of MAPK and Wnt members were performed, followed by analysis of spheroid interactions between human endometrial cells and extravillous trophoblast cells. By mimicking embryo contact using IL-1β, we showed less ERK and c-Jun activation by depletion of Syndecan-1 and less Frizzled 4 production as part of the canonical Wnt pathway. Additionally, more beta-catenin was phosphorylated and therefore degraded after depletion of Syndecan-1. Secretion of CXC motif ligand 1 depends on MEK-1 with respect to Syndecan-1. Regarding the interaction of endometrial and trophoblast cells, the spheroid center-to-center distances were smaller after depletion of Syndecan-1. Therefore, Syndecan-1 seems to affect signaling processes relevant to signaling and intercellular interaction at the trophoblast-decidual interface.

  19. Photoperiodic regulation of cellular retinol binding protein, CRBP1 [corrected] and nestin in tanycytes of the third ventricle ependymal layer of the Siberian hamster.

    Science.gov (United States)

    Barrett, Perry; Ivanova, Elena; Graham, E Scott; Ross, Alexander W; Wilson, Dana; Plé, Helene; Mercer, Julian G; Ebling, Francis J; Schuhler, Sandrine; Dupré, Sandrine M; Loudon, Andrew; Morgan, Peter J

    2006-12-01

    Tanycytes in the ependymal layer of the third ventricle act both as a barrier and a communication gateway between the cerebrospinal fluid, brain and portal blood supply to the pituitary gland. However, the range, importance and mechanisms involved in the function of tanycytes remain to be explored. In this study, we have utilized a photoperiodic animal to examine the expression of three unrelated gene sequences in relation to photoperiod-induced changes in seasonal physiology and behaviour. We demonstrate that cellular retinol binding protein [corrected] (CRBP1), a retinoic acid transport protein, GPR50, an orphan G-protein-coupled receptor and nestin, an intermediate filament protein, are down-regulated in short-day photoperiods. The distribution of the three sequences is very similar, with expression located in cells with tanycyte morphology in the region of the ependymal layer where tanycytes are located. Furthermore, CRBP1 expression in the ependymal layer is shown to be independent of a circadian clock and altered testosterone levels associated with testicular regression in short photo-period. Pinealectomy of Siberian hamsters demonstrates CRBP1 expression is likely to be dependent on melatonin output from the pineal gland. This provides evidence that tanycytes are seasonally responsive cells and are likely to be an important part of the mechanism to facilitate seasonal physiology and behaviour in the Siberian hamster.

  20. An integrated transcriptomics-guided genome-wide promoter analysis and next-generation proteomics approach to mine factor(s) regulating cellular differentiation

    Science.gov (United States)

    Mandal, Kamal; Bader, Samuel L.; Kumar, Pankaj; Malakar, Dipankar; Campbell, David S.; Pradhan, Bhola Shankar; Sarkar, Rajesh K.; Wadhwa, Neerja; Sensharma, Souvik; Jain, Vaibhav; Moritz, Robert L.

    2017-01-01

    Abstract Differential next-generation-omics approaches aid in the visualization of biological processes and pave the way for divulging important events and/or interactions leading to a functional output at cellular or systems level. To this end, we undertook an integrated Nextgen transcriptomics and proteomics approach to divulge differential gene expression of infant and pubertal rat Sertoli cells (Sc).Unlike, pubertal Sc, infant Sc are immature and fail to support spermatogenesis. We found exclusive association of 14 and 19 transcription factor binding sites to infantile and pubertal states of Sc, respectively, using differential transcriptomics-guided genome-wide computational analysis of relevant promoters employing 220 Positional Weight Matrices from the TRANSFAC database. Proteomic SWATH-MS analysis provided extensive quantification of nuclear and cytoplasmic protein fractions revealing 1,670 proteins differentially located between the nucleus and cytoplasm of infant Sc and 890 proteins differentially located within those of pubertal Sc. Based on our multi-omics approach, the transcription factor YY1 was identified as one of the lead candidates regulating differentiation of Sc.YY1 was found to have abundant binding sites on promoters of genes upregulated during puberty. To determine its significance, we generated transgenic rats with Sc specific knockdown of YY1 that led to compromised spermatogenesis. PMID:28065881

  1. Cellular Phone Towers, Reno County and City of Hutchinson Area Towers point file, Published in 2007, 1:600 (1in=50ft) scale, City of Hutchinson.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Cellular Phone Towers dataset, published at 1:600 (1in=50ft) scale, was produced all or in part from Orthoimagery information as of 2007. It is described as...

  2. Engineering Cellular Metabolism

    DEFF Research Database (Denmark)

    Nielsen, Jens; Keasling, Jay

    2016-01-01

    of metabolic engineering and will discuss how new technologies can enable metabolic engineering to be scaled up to the industrial level, either by cutting off the lines of control for endogenous metabolism or by infiltrating the system with disruptive, heterologous pathways that overcome cellular regulation....

  3. Management of groundwater in farmed pond area using risk-based regulation.

    Science.gov (United States)

    Huang, Jun-Ying; Liao, Chiao-Miao; Lin, Kao-Hung; Lee, Cheng-Haw

    2014-09-01

    Blackfoot disease (BFD) had occurred seriously in the Yichu, Hsuehchia, Putai, and Peimen townships of Chia-Nan District of Taiwan in the early days. These four townships are the districts of fishpond cultivation domestically in Taiwan. Groundwater becomes the main water supply because of short income in surface water. The problems of over pumping in groundwater may not only result in land subsidence and seawater intrusion but also be harmful to the health of human giving rise to the bioaccumulation via food chain in groundwater with arsenic (As). This research uses sequential indicator simulation (SIS) to characterize the spatial arsenic distribution in groundwater in the four townships. Risk assessment is applied to explore the dilution ratio (DR) of groundwater utilization, which is defined as the ratio showing the volume of groundwater utilization compared to pond water, for fish farming in the range of target cancer risk (TR) especially on the magnitude of 10(-4)~10(-6). Our study results reveal that the 50th percentile of groundwater DRs served as a regulation standard can be used to perform fish farm groundwater management for a TR of 10(-6). For a TR of 5 × 10(-6), we suggest using the 75th percentile of DR for groundwater management. For a TR of 10(-5), we suggest using the 95th percentile of the DR standard for performing groundwater management in fish farm areas. For the TR of exceeding 5 × 10(-5), we do not suggest establishing groundwater management standards under these risk standards. Based on the research results, we suggest that establishing a TR at 10(-5) and using the 95th percentile of DR are best for groundwater management in fish farm areas.

  4. Importance of the alternative oxidase (AOX) pathway in regulating cellular redox and ROS homeostasis to optimize photosynthesis during restriction of the cytochrome oxidase pathway in Arabidopsis thaliana.

    Science.gov (United States)

    Vishwakarma, Abhaypratap; Tetali, Sarada Devi; Selinski, Jennifer; Scheibe, Renate; Padmasree, Kollipara

    2015-09-01

    The importance of the alternative oxidase (AOX) pathway, particularly AOX1A, in optimizing photosynthesis during de-etiolation, under elevated CO2, low temperature, high light or combined light and drought stress is well documented. In the present study, the role of AOX1A in optimizing photosynthesis was investigated when electron transport through the cytochrome c oxidase (COX) pathway was restricted at complex III. Leaf discs of wild-type (WT) and aox1a knock-out mutants of Arabidopsis thaliana were treated with antimycin A (AA) under growth-light conditions. To identify the impact of AOX1A deficiency in optimizing photosynthesis, respiratory O2 uptake and photosynthesis-related parameters were measured along with changes in redox couples, reactive oxygen species (ROS), lipid peroxidation and expression levels of genes related to respiration, the malate valve and the antioxidative system. In the absence of AA, aox1a knock-out mutants did not show any difference in physiological, biochemical or molecular parameters compared with WT. However, after AA treatment, aox1a plants showed a significant reduction in both respiratory O2 uptake and NaHCO3-dependent O2 evolution. Chlorophyll fluorescence and P700 studies revealed that in contrast to WT, aox1a knock-out plants were incapable of maintaining electron flow in the chloroplastic electron transport chain, and thereby inefficient heat dissipation (low non-photochemical quenching) was observed. Furthermore, aox1a mutants exhibited significant disturbances in cellular redox couples of NAD(P)H and ascorbate (Asc) and consequently accumulation of ROS and malondialdehyde (MDA) content. By contrast, WT plants showed a significant increase in transcript levels of CSD1, CAT1, sAPX, COX15 and AOX1A in contrast to aox1a mutants. These results suggest that AOX1A plays a significant role in sustaining the chloroplastic redox state and energization to optimize photosynthesis by regulating cellular redox homeostasis and ROS

  5. 36 CFR 3.17 - What regulations apply to swimming areas and beaches?

    Science.gov (United States)

    2010-07-01

    ... swimming areas and beaches? 3.17 Section 3.17 Parks, Forests, and Public Property NATIONAL PARK SERVICE... and beaches? (a) The superintendent may designate areas as swimming areas or swimming beaches in... flotation devices, glass containers, kites, or incompatible activities in swimming areas or swimming...

  6. Tandem E2F binding sites in the promoter of the p107 cell cycle regulator control p107 expression and its cellular functions.

    Directory of Open Access Journals (Sweden)

    Deborah L Burkhart

    2010-06-01

    Full Text Available The retinoblastoma tumor suppressor (Rb is a potent and ubiquitously expressed cell cycle regulator, but patients with a germline Rb mutation develop a very specific tumor spectrum. This surprising observation raises the possibility that mechanisms that compensate for loss of Rb function are present or activated in many cell types. In particular, p107, a protein related to Rb, has been shown to functionally overlap for loss of Rb in several cellular contexts. To investigate the mechanisms underlying this functional redundancy between Rb and p107 in vivo, we used gene targeting in embryonic stem cells to engineer point mutations in two consensus E2F binding sites in the endogenous p107 promoter. Analysis of normal and mutant cells by gene expression and chromatin immunoprecipitation assays showed that members of the Rb and E2F families directly bound these two sites. Furthermore, we found that these two E2F sites controlled both the repression of p107 in quiescent cells and also its activation in cycling cells, as well as in Rb mutant cells. Cell cycle assays further indicated that activation of p107 transcription during S phase through the two E2F binding sites was critical for controlled cell cycle progression, uncovering a specific role for p107 to slow proliferation in mammalian cells. Direct transcriptional repression of p107 by Rb and E2F family members provides a molecular mechanism for a critical negative feedback loop during cell cycle progression and tumorigenesis. These experiments also suggest novel therapeutic strategies to increase the p107 levels in tumor cells.

  7. Immunohistochemical cellular distribution of proteins related to M phase regulation in early proliferative lesions induced by tumor promotion in rat two-stage carcinogenesis models.

    Science.gov (United States)

    Yafune, Atsunori; Taniai, Eriko; Morita, Reiko; Akane, Hirotoshi; Kimura, Masayuki; Mitsumori, Kunitoshi; Shibutani, Makoto

    2014-01-01

    We have previously reported that 28-day treatment with hepatocarcinogens increases liver cells expressing p21(Cip1), a G1/S checkpoint protein, and M phase proteins, i.e., nuclear Cdc2, Aurora B, phosphorylated-Histone H3 (p-Histone H3) and heterochromatin protein 1α (HP1α), in rats. To examine the roles of these markers in the early stages of carcinogenesis, we investigated their cellular distribution in several carcinogenic target organs using rat two-stage carcinogenesis models. Promoting agents targeting the liver (piperonyl butoxide and methapyrilene hydrochloride), thyroid (sulfadimethoxine), urinary bladder (phenylethyl isothiocyanate), and forestomach and glandular stomach (catechol) were administered to rats after initiation treatment for the liver with N-diethylnitrosamine, thyroid with N-bis(2-hydroxypropyl)nitrosamine, urinary bladder with N-butyl-N-(4-hydroxybutyl)nitrosamine, and forestomach and glandular stomach with N-methyl-N'-nitro-N-nitrosoguanidine. Numbers of cells positive for nuclear Cdc2, Aurora B, p-Histone H3 and HP1α increased within preneoplastic lesions as determined by glutathione S-transferase placental form in the liver or phosphorylated p44/42 mitogen-activated protein kinase in the thyroid, and hyperplastic lesions having no known preneoplastic markers in the urinary bladder, forestomach and glandular stomach. Immunoreactive cells for p21(Cip1) were decreased within thyroid preneoplastic lesions; however, they were increased within liver preneoplastic lesions and hyperplastic lesions in other organs. These results suggest that M phase disruption commonly occur during the formation of preneoplastic lesions and hyperplastic lesions. Differences in the expression patterns of p21(Cip1) between thyroid preneoplastic and proliferative lesions in other organs may reflect differences in cell cycle regulation involving G1/S checkpoint function between proliferative lesions in each organ.

  8. Cellular inhibitors of apoptosis are global regulators of NF-κB and MAPK activation by members of the TNF family of receptors.

    Science.gov (United States)

    Varfolomeev, Eugene; Goncharov, Tatiana; Maecker, Heather; Zobel, Kerry; Kömüves, László G; Deshayes, Kurt; Vucic, Domagoj

    2012-03-20

    Tumor necrosis factor (TNF) family members are essential for the development and proper functioning of the immune system. TNF receptor (TNFR) signaling is mediated through the assembly of protein signaling complexes that activate the nuclear factor κB (NF-κB) and mitogen-activated protein kinase (MAPK) pathways in a ubiquitin-dependent manner. The cellular inhibitor of apoptosis (c-IAP) proteins c-IAP1 and c-IAP2 are E3 ubiquitin ligases that are recruited to TNFR signaling complexes through their constitutive association with the adaptor protein TNFR-associated factor 2 (TRAF2). We demonstrated that c-IAP1 and c-IAP2 were required for canonical activation of NF-κB and MAPK by members of the TNFR family. c-IAPs were required for the recruitment of inhibitor of κB kinase β (IKKβ), the IKK regulatory subunit NF-κB essential modulator (NEMO), and RBCK1/Hoil1-interacting protein (HOIP) to TNFR signaling complexes and the induction of gene expression by TNF family members. In contrast, TNFRs that stimulated the noncanonical NF-κB pathway triggered translocation of c-IAPs, TRAF2, and TRAF3 from the cytosol to membrane fractions, which led to their proteasomal and lysosomal degradation. Finally, we established that signaling by B cell-activating factor receptor 3 induced the cytosolic depletion of TRAF3, which enabled noncanonical NF-κB activation. These results define c-IAP proteins as critical regulators of the activation of NF-κB and MAPK signaling pathways by members of the TNFR superfamily.

  9. Cellular Telephone

    Institute of Scientific and Technical Information of China (English)

    杨周

    1996-01-01

    Cellular phones, used in automobiles, airliners, and passenger trains, are basically low-power radiotelephones. Calls go through radio transmitters that are located within small geographical units called cells. Because each cell’s signals are too weak to interfere with those of other cells operating on the same fre-

  10. MiRNA-205 modulates cellular invasion and migration via regulating zinc finger E-box binding homeobox 2 expression in esophageal squamous cell carcinoma cells

    Directory of Open Access Journals (Sweden)

    Yamashita Shunichi

    2011-03-01

    Full Text Available Abstract Background Esophageal squamous cell carcinoma (ESCC is often diagnosed at later stages until they are incurable. MicroRNA (miR is a small, non-coding RNA that negatively regulates gene expression mainly via translational repression. Accumulating evidence indicates that deregulation of miR is associated with human malignancies including ESCC. The aim of this study was to identify miR that could be specifically expressed and exert distinct biological actions in ESCC. Methods Total RNA was extracted from ESCC cell lines, OE21 and TE10, and a non-malignant human esophageal squamous cell line, Het-1A, and subjected to microarray analysis. Expression levels of miR that showed significant differences between the 2 ESCC and Het-1A cells based on the comprehensive analysis were analyzed by the quantitative reverse transcriptase (RT-PCR method. Then, functional analyses, including cellular proliferation, apoptosis and Matrigel invasion and the wound healing assay, for the specific miR were conducted. Using ESCC tumor samples and paired surrounding non-cancerous tissue obtained endoscopically, the association with histopathological differentiation was examined with quantitative RT-PCR. Results Based on the miR microarray analysis, there were 14 miRs that showed significant differences (more than 2-fold in expression between the 2 ESCC cells and non-malignant Het-1A. Among the significantly altered miRs, miR-205 expression levels were exclusively higher in 5 ESCC cell lines examined than any other types of malignant cell lines and Het-1A. Thus, miR-205 could be a specific miR in ESCC. Modulation of miR-205 expression by transfection with its precursor or anti-miR-205 inhibitor did not affect ESCC cell proliferation and apoptosis, but miR-205 was found to be involved in cell invasion and migration. Western blot revealed that knockdown of miR-205 expression in ESCC cells substantially enhanced expression of zinc finger E-box binding homeobox 2

  11. 77 FR 69761 - Regulated Navigation Area; Recovery Operations, the Port of New York and New Jersey, NJ and NY

    Science.gov (United States)

    2012-11-21

    ... waterway users, the public, and pollution response and recovery workers for the duration of the response... vessels could pose significant risk of injury or death to response and recovery workers. Certain portions... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA11 Regulated Navigation Area; Recovery Operations, the...

  12. 76 FR 80211 - Irish Potatoes Grown in Colorado; Modification of the Handling Regulation for Area No. 3

    Science.gov (United States)

    2011-12-23

    ... in the market. The changes are expected to increase sales of Colorado potatoes and to benefit the...] [Pages 80211-80214] [FR Doc No: 2011-32927] DEPARTMENT OF AGRICULTURE Agricultural Marketing Service 7... of the Handling Regulation for Area No. 3 AGENCY: Agricultural Marketing Service, USDA. ACTION: Final...

  13. 78 FR 3 - Irish Potatoes Grown in Colorado; Modification of the Handling Regulation for Area No. 2

    Science.gov (United States)

    2013-01-02

    ... Agricultural Marketing Service 7 CFR Part 948 Irish Potatoes Grown in Colorado; Modification of the Handling... comments. SUMMARY: This rule modifies the grade requirements for potatoes handled under the Colorado potato marketing order, Area No. 2 (order). The order regulates the handling of Irish potatoes grown in Colorado...

  14. 7 CFR 301.75-8 - Interstate movement of regulated seed from a quarantined area.

    Science.gov (United States)

    2010-01-01

    ... (Continued) ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE DOMESTIC QUARANTINE NOTICES Citrus Canker Notice of Quarantine and Regulations § 301.75-8 Interstate movement of regulated seed from... interstate movement, no plants or plant parts infected with or exposed to citrus canker were found in...

  15. 78 FR 28170 - Regulated Navigation Area; Southern Oahu Tsunami Vessel Evacuation; Honolulu, HI

    Science.gov (United States)

    2013-05-14

    ... Evacuation; Honolulu, HI AGENCY: Coast Guard, DHS. ACTION: Notice of proposed rulemaking. SUMMARY: The Coast... waters contained within an area composing of an area on the southern side of Oahu, HI. The RNA...

  16. 75 FR 61096 - Regulated Navigation Area; Reserved Channel, Boston Harbor, Boston, MA

    Science.gov (United States)

    2010-10-04

    ... Harbor, Boston, MA AGENCY: Coast Guard, DHS. ACTION: Temporary final rule. SUMMARY: The Coast Guard is... Navigation Areas: Reserved Channel, Boston Harbor, Boston, MA (a) Location. The following areas are...

  17. Epigenetics and Cellular Metabolism

    Science.gov (United States)

    Xu, Wenyi; Wang, Fengzhong; Yu, Zhongsheng; Xin, Fengjiao

    2016-01-01

    Living eukaryotic systems evolve delicate cellular mechanisms for responding to various environmental signals. Among them, epigenetic machinery (DNA methylation, histone modifications, microRNAs, etc.) is the hub in transducing external stimuli into transcriptional response. Emerging evidence reveals the concept that epigenetic signatures are essential for the proper maintenance of cellular metabolism. On the other hand, the metabolite, a main environmental input, can also influence the processing of epigenetic memory. Here, we summarize the recent research progress in the epigenetic regulation of cellular metabolism and discuss how the dysfunction of epigenetic machineries influences the development of metabolic disorders such as diabetes and obesity; then, we focus on discussing the notion that manipulating metabolites, the fuel of cell metabolism, can function as a strategy for interfering epigenetic machinery and its related disease progression as well. PMID:27695375

  18. 15 CFR 922.164 - Additional activity regulations by Sanctuary area.

    Science.gov (United States)

    2010-01-01

    ... known as spearguns. (2) Great White Heron and Key West National Wildlife Refuge Management Areas... of the Great White Heron and Key West National Wildlife Refuge Management Areas described in Appendix... a Special-use Area except to conduct or cause to be conducted the following activities: (i) In such...

  19. 78 FR 27132 - Special Regulations of the National Park Service, Curecanti National Recreation Area, Snowmobiles...

    Science.gov (United States)

    2013-05-09

    ...)). Off Road Vehicles Paragraph 7.51(e) would be added to designate routes and areas where motor vehicles... additions read as follows: Sec. 7.51 Curecanti Recreation Area. * * * * * (c) Snowmobiles. Snowmobiles are..., Curecanti National Recreation Area, Snowmobiles and Off-Road Motor Vehicles AGENCY: National Park...

  20. Connectivity analysis of suggestive brain areas involved in middle ear pressure regulation in humans

    DEFF Research Database (Denmark)

    SA, Sami; Gaihede, Michael

    2010-01-01

    , MEP counter-regulation presented as Eustachian tube openings with steep and fast pressure changes toward 0 Pa, whereas in others, gradual and slow pressure changes presented related to the mastoid; these changes sometimes crossed 0 Pa into opposite pressures. In many cases, combinations......HYPOTHESIS:: Middle ear pressure (MEP) is actively regulated by both the Eustachian tube and the mastoid air cell system. BACKGROUND:: MEP is a highly significant factor involved in many clinical conditions related to otitis media. Basic knowledge on its overall regulation remains insufficient...... of these distinct mechanisms were found. CONCLUSION:: The human mastoid as well as the Eustachian tube was capable of active counter-regulation of the MEP in short-term experimental pressure changes in healthy ears. Thus, these 2 systems seemed to function in a complementary way, where the mastoid was related...

  1. 77 FR 9852 - Special Regulations; Areas of the National Park System, Cape Cod National Seashore

    Science.gov (United States)

    2012-02-21

    .... DATES: This rule is effective March 22, 2012. FOR FURTHER INFORMATION CONTACT: Craig Thatcher, Acting... primary authors of this regulation were Craig Thatcher, Acting Chief Ranger, Cape Cod National...

  2. 75 FR 39632 - Regulated Navigation Area; Gulf Intracoastal Waterway, Inner Harbor Navigation Canal, Harvey...

    Science.gov (United States)

    2010-07-12

    ..., Inner Harbor Navigation Canal, Harvey Canal, Algiers Canal, New Orleans, LA; Correction ACTION: Interim... Navigation Canal, Harvey Canal, Algiers Canal, New Orleans, LA into the Code of Federal Regulations....

  3. 78 FR 61223 - Regulated Navigation Area; Southern Oahu Tsunami Vessel Evacuation, Honolulu, HI

    Science.gov (United States)

    2013-10-03

    ... him. The graphic was also disseminated via press release, advertised on the local TV news and posted..., Oahu, Hawaii, chart 19357. (b) Regulations. You may contact the Coast Guard on VHF Channel 16...

  4. Role of AREA, a regulator of nitrogen metabolism, during colonization of maize kernels and fumonisin biosynthesis in Fusarium verticillioides.

    Science.gov (United States)

    Kim, Hun; Woloshuk, C P

    2008-06-01

    Fumonisin B1 (FB(1)) biosynthesis is repressed in cultures containing ammonium as the nitrogen source and when grown on blister kernels, the earliest stages of kernel development. In this study AREA, a regulator of nitrogen metabolism, was disrupted in Fusarium verticilliodes. The mutant (DeltaareA) grew poorly on mature maize kernels, but grew similar to wild type (WT) with the addition of ammonium phosphate. FB(1) was not produced by DeltaareA under any condition or by the WT with added ammonium phosphate. Constitutive expression of AREA (strain AREA-CE) rescued the growth and FB(1) defects in DeltaareA. Growth of WT, DeltaareA, and AREA-CE on blister-stage kernels was similar. After 7 days of growth, none of the strains produced FB(1) and the pH of the kernel tissues was 8.0. Addition of amylopectin to the blister kernels resulted in a pH near 6.6 and FB(1) production by WT and AREA-CE. The results support the hypothesis that FB(1) biosynthesis is regulated by AREA. Also the failure to produce FB(1) in blister kernels is due to high pH conditions generated because of an unfavorable carbon/nitrogen environment.

  5. Translational regulation of HIV-1 replication by HIV-1 Rev cellular cofactors Sam68, eIF5A, hRIP, and DDX3.

    Science.gov (United States)

    Liu, Jinfeng; Henao-Mejia, Jorge; Liu, Hao; Zhao, Yingren; He, Johnny J

    2011-06-01

    Nuclear export and translation of HIV-1 RNA are two important posttranscriptional events for HIV-1 gene expression and replication. HIV-1 Rev functions to export unspliced and incompletely spliced HIV-1 RNA from the nucleus to the cytoplasm; it requires interaction with several cellular cofactors such as Sam68, eIF5A, hRIP, and DDX3. Meanwhile, some studies have also implicated Rev and some of its cofactors such as Sam68 in HIV-1 RNA translation. Thus, in this study, we aimed to characterize the potential function of all these four Rev cofactors in HIV-1 RNA translation. Ectopic expression, siRNA knockdown, and trans-complementation assays confirmed that all these cofactors were very important for HIV-1 gene expression and production through Rev and, accordingly, Rev-dependent reporter gene expression. Importantly, these studies revealed for the first time that each of these cofactors also regulated Rev-independent reporter gene expression. To directly determine the roles of these cofactors in HIV-1 RNA translation, we designed and synthesized a full-length capped HIV-1 RNA in vitro, transfected it into cells to bypass the RNA nuclear export step, and determined HIV-1 Gag expression from the cytoplasmic RNA in the cells that had ectopically expressed or siRNA knocked down cofactors. Gag expression was found to closely correlate with the expression levels of all these cofactors. Furthermore, we took advantage of a HIV-1 internal ribosomal entry site (IRES)-based bicistronic reporter gene assay and determined the effects of these cofactors on cap-independent IRES-mediated HIV-1 translation. The results showed that DDX3, eIF5A, and hRIP enhanced HIV-1 IRES-mediated translation, whereas Sam68 did not. Taken together, these results show that HIV-1 Rev cofactors Sam68, eIF5A, hRIP, and DDX3 also function in the translation of HIV-1 RNA and suggest that the regulatory mechanisms of HIV-1 RNA translation are likely different among these cofactors.

  6. 78 FR 63069 - Special Regulations; Areas of the National Park System; Yellowstone National Park; Winter Use

    Science.gov (United States)

    2013-10-23

    ... vehicles. The exercise of the NPS Organic Act authority is not an effort by NPS to regulate manufacturers... vans, sport utility vehicles, or light- or medium-duty buses that have been converted for oversnow... the functional equivalent of 2010 (or newer) EPA Tier 2 Model Year engine and emission...

  7. 76 FR 15888 - Special Regulations; Areas of the National Park System, Cape Cod National Seashore

    Science.gov (United States)

    2011-03-22

    ... among others, the Highland Fish and Game Club, the Brewster Rod and Gun Club and the Bass River Rod and... regulation were Stephen Prokop, former Chief Ranger CACO; Bob Grant, Chief Ranger CACO; Carrie Phillips... 14, 2011. Will Shafroth, Acting Assistant Secretary for Fish and Wildlife and Parks. BILLING...

  8. 78 FR 1145 - Regulated Navigation Area; Housatonic River, Bridge Replacement Operations; Stratford, CT

    Science.gov (United States)

    2013-01-08

    ... on the human environment. This rule involves restricting vessel movement within a regulated... hand delivery, but please use only one of these means. If you submit a comment online, it will be considered received by the Coast Guard when you successfully transmit the comment. If you fax, hand...

  9. 78 FR 67300 - Anchorage Regulations: Pacific Ocean at San Nicolas Island, Calif.; Restricted Anchorage Areas

    Science.gov (United States)

    2013-11-12

    ..., go to http://www.regulations.gov , type the docket number USCG-2012-0967 in the ``SEARCH'' box and...'' box and click ``SEARCH.'' Click on Open Docket Folder on the line associated with this rulemaking. You... Beach and the explosives safety arc around the Barge Pier at Daytona Beach (see figure 2 located in...

  10. 78 FR 14447 - Special Regulations; Areas of the National Park System, Chattahoochee River National Recreation...

    Science.gov (United States)

    2013-03-06

    ... the developed, natural area recreation, and rustic zones. History of Trail Development This rule adds... opportunities for mountain biking will increase tourism and benefit local economies. ] One comment expressed a...

  11. 75 FR 39168 - Special Regulations; Areas of the National Park System

    Science.gov (United States)

    2010-07-08

    ... dining room and upstairs bedroom areas for cleaning, repairing, and reinstallation by a paper conservator... activities to proceed safely and efficiently in order to carry out the protection and preservation of...

  12. 33 CFR 165.811 - Atchafalaya River, Berwick Bay, LA-regulated navigation area.

    Science.gov (United States)

    2010-07-01

    ... navigation area: the waters of the Atchafalaya River in Berwick Bay bounded on the northside from 2,000 yards... length. Note: The variation in the draft and the beam of the barges in a multi-barge tow should...

  13. Human-related factors regulate the spatial ecology of domestic cats in sensitive areas for conservation.

    Directory of Open Access Journals (Sweden)

    Joaquim P Ferreira

    Full Text Available BACKGROUND: Domestic cats ranging freely in natural areas are a conservation concern due to competition, predation, disease transmission or hybridization with wildcats. In order to improve our ability to design effective control policies, we investigate the factors affecting their numbers and space use in natural areas of continental Europe. METHODOLOGY/PRINCIPAL FINDINGS: We describe the patterns of cat presence, abundance and space use and analyse the associated environmental and human constraints in a well-preserved Mediterranean natural area with small scattered local farms. We failed in detecting cats in areas away from human settlements (trapping effort above 4000 trap-nights, while we captured 30 individuals near inhabited farms. We identified 130 cats, all of them in farms still in use by people (30% of 128 farms. All cats were free-ranging and very wary of people. The main factor explaining the presence of cats was the presence of people, while the number of cats per farm was mostly affected by the occasional food provisioning with human refuse and the presence of people. The home ranges of eight radio tagged cats were centred at inhabited farms. Males went furthest away from the farms during the mating season (3.8 km on average, maximum 6.3 km, using inhabited farms as stepping-stones in their mating displacements (2.2 km of maximum inter-farm distance moved. In their daily movements, cats notably avoided entering in areas with high fox density. CONCLUSIONS: The presence, abundance and space use of cats were heavily dependent on human settlements. Any strategy aiming at reducing their impact in areas of conservation concern should aim at the presence of settlements and their spatial spread and avoid any access to human refuse. The movements of domestic cats would be limited in areas with large patches of natural vegetation providing good conditions for other carnivore mammals such as red foxes.

  14. Distributed Hierarchical Control of Multi-Area Power Systems with Improved Primary Frequency Regulation

    Energy Technology Data Exchange (ETDEWEB)

    Lian, Jianming; Marinovici, Laurentiu D.; Kalsi, Karanjit; Du, Pengwei; Elizondo, Marcelo A.

    2012-12-12

    The conventional distributed hierarchical control architecture for multi-area power systems is revisited. In this paper, a new distributed hierarchical control architecture is proposed. In the proposed architecture, pilot generators are selected in each area to be equipped with decentralized robust control as a supplementary to the conventional droop speed control. With the improved primary frequency control, the system frequency can be restored to the nominal value without the help of secondary frequency control, which reduces the burden of the automatic generation control for frequency restoration. Moreover, the low frequency inter-area electromechanical oscillations can also be effectively damped. The effectiveness of the proposed distributed hierarchical control architecture is validated through detailed simulations.

  15. 75 FR 68942 - Karnal Bunt; Regulated Areas in Arizona, California, and Texas

    Science.gov (United States)

    2010-11-10

    ... (Triticum aestivum), durum wheat (Triticum durum), and triticale (Triticum aestivum X Secale cereale), a... planted with seed from a lot found to contain a bunted wheat kernel; A distinct definable area that... total of 5 years (the years need not be consecutive). After tilling, the field may be planted with...

  16. 75 FR 49843 - Regulated Navigation Area; Boom Deployment Strategy Testing, Great Bay, NH

    Science.gov (United States)

    2010-08-16

    ... must reach the Coast Guard on or before September 15, 2010. ADDRESSES: You may submit comments... designed to protect sensitive environmental areas in the event of an oil or chemical spill in navigable... could be ordered to wait until the current has subsided and the boom removed to allow for safe...

  17. 75 FR 39839 - Regulated Navigation Area; Hudson River and Port of NY/NJ

    Science.gov (United States)

    2010-07-13

    ... restrictions with the Kiewit and Weeks Marine contractors, and with Hudson River and Sandy Hook Pilots... transfer of the bridge span from shore to the barges has been scheduled on a weekday when it is expected to... Overtaking zones are established in areas identified by Weeks Marine, Hudson River and Sandy Hook Pilots as...

  18. Up-regulation of Na + expression in the area postrema of total sleep deprived rats by TOF-SIMS analysis

    Science.gov (United States)

    Mai, Fu-Der; Chen, Bo-Jung; Ling, Yong-Chien; Wu, Un-In; Huang, Yi-Lun; Chang, Hung-Ming

    2008-12-01

    Area postrema (AP) is a circumventricular organ plays an important role in sodium homeostasis and cardiovascular regulation. Since sleep deficiency will cause cardiovascular dysfunction, the present study aims to determine whether sodium level would significantly alter in AP following total sleep deprivation (TSD). Sodium level was investigated in vivo by time-of-flight secondary ion mass spectrometry (TOF-SIMS). Clinical manifestation of cardiovascular function was demonstrated by mean arterial pressure (MAP) values. Results indicated that in normal rats, TOF-SIMS spectrum revealed a major peak of sodium ion counting as 5.61 × 10 5 at m/ z 23. The sodium ions were homogeneous distributed in AP without specific localization. However, following TSD, the sodium intensity was relatively increased (6.73 × 10 5) and the signal for sodium image was strongly expressed throughout AP with definite spatial distribution. MAP of TSD rats is 138 ± 5 mmHg, which is significantly higher than that of normal ones (121 ± 3 mmHg). Regarding AP is an important area for sodium sensation and development of hypernatremic related sympatho-excitation; up-regulation of sodium expression following TSD suggests that high sodium level might over-activate AP, through complex neuronal networks involving in sympathetic regulation, which could lead to the formation of TSD relevant cardiovascular diseases.

  19. Campylobacter jejuni CsrA complements an Escherichia coli csrA mutation for the regulation of biofilm formation, motility and cellular morphology but not glycogen accumulation

    OpenAIRE

    Fields Joshua A; Thompson Stuart A

    2012-01-01

    Abstract Background Although Campylobacter jejuni is consistently ranked as one of the leading causes of bacterial diarrhea worldwide, the mechanisms by which C. jejuni causes disease and how they are regulated have yet to be clearly defined. The global regulator, CsrA, has been well characterized in several bacterial genera and is known to regulate a number of independent pathways via a post transcriptional mechanism, but remains relatively uncharacterized in the genus Campylobacter. Previou...

  20. Molecular and Cellular Signaling

    CERN Document Server

    Beckerman, Martin

    2005-01-01

    A small number of signaling pathways, no more than a dozen or so, form a control layer that is responsible for all signaling in and between cells of the human body. The signaling proteins belonging to the control layer determine what kinds of cells are made during development and how they function during adult life. Malfunctions in the proteins belonging to the control layer are responsible for a host of human diseases ranging from neurological disorders to cancers. Most drugs target components in the control layer, and difficulties in drug design are intimately related to the architecture of the control layer. Molecular and Cellular Signaling provides an introduction to molecular and cellular signaling in biological systems with an emphasis on the underlying physical principles. The text is aimed at upper-level undergraduates, graduate students and individuals in medicine and pharmacology interested in broadening their understanding of how cells regulate and coordinate their core activities and how diseases ...

  1. Intermolecular masking of the HIV-1 Rev NLS by the cellular protein HIC: novel insights into the regulation of Rev nuclear import.

    LENUS (Irish Health Repository)

    Gu, Lili

    2011-01-01

    The HIV-1 regulatory protein Rev, which is essential for viral replication, mediates the nuclear export of unspliced viral transcripts. Rev nuclear function requires active nucleocytoplasmic shuttling, and Rev nuclear import is mediated by the recognition of its Nuclear Localisation Signal (NLS) by multiple import factors, which include transportin and importin β. However, it remains unclear which nuclear import pathway(s) predominate in vivo, and the cellular environment that modulates Rev nucleocytoplasmic shuttling remains to be characterised.

  2. ANK1 is up-regulated in laser captured microglia in Alzheimer?s brain; the importance of addressing cellular heterogeneity

    OpenAIRE

    Mastroeni, Diego; Sekar, Shobana; Nolz, Jennifer; Delvaux, Elaine; Lunnon, Katie; Mill, Jonathan; Liang, Winnie S.; Coleman, Paul D.

    2017-01-01

    Recent epigenetic association studies have identified a new gene, ANK1, in the pathogenesis of Alzheimer?s disease (AD). Although strong associations were observed, brain homogenates were used to generate the data, introducing complications because of the range of cell types analyzed. In order to address the issue of cellular heterogeneity in homogenate samples we isolated microglial, astrocytes and neurons by laser capture microdissection from CA1 of hippocampus in the same individuals with ...

  3. Protein tyrosine phosphatase is possibly involved in cellular signal transduction and the regulation of ABA accumulation in response to water deficit in Maize L. coleoptile

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Water deficit-induced ABA accumulation is an ideal model or "stimulus-response" system to investigate cellular stress signaling in plant cells, using such a model the cellular stress signaling triggered by water deficit was investigated in Maize L. coleoptile. Water deficit-induced ABA accumulation was sensitively blocked by NaVO3, a potent inhibitor both to plasma membrane H+-ATPase (PM-H+- ATPase) and protein tyrosine phosphatase (PTPase). However, while PM- H+-ATPase activity was unaffected under water deficit and PM- H+-ATPase activator did not induce an ABA accumulation instead of water deficit, water deficit induced an increase in the protein phosphatase activity, and furthermore, ABA accumulation was inhibited by PAO, a specific inhibitor of PTPase. These results indicate that protein phosphtases may be involved in the cellular signaling in response to water deficit. Further studies identified at least four species of protein phosphtase as assayed by using pNPP as substrate, among which one component was especially sensitive to NaVO3. The NaVO3-sensitive enzyme was purified and finally showed a protein band about 66 kD on SDS/PAGE. The purified enzyme showed a great activity to some specific PTPase substrates at pH 6.0. In addition to NaVO3, the enzyme was also sensitive to some other PTPase inhibitors such as Zn2+ and MO33+, but not to Ca2+ and Mg2+, indicating that it might be a protein tyrosine phosphatase. Interestingly, the purified enzyme could be deactivated by some reducing agent DTT, which was previously proved to be an inhibitor of water deficit-induced ABA accumulation. This result further proved that PTPase might be involved in the cellular signaling of ABA accumulation in response to water deficit.

  4. The AMPK enzyme-complex: From the regulation of cellular energy homeostasis to a possible new molecular target in the management of chronic inflammatory disorders

    NARCIS (Netherlands)

    Antonioli, Luca; Colucci, Rocchina; Pellegrini, Carolina; Giustarini, Giulio; Sacco, Deborah; Tirotta, Erika; Caputi, Valentina; Marsilio, Ilaria; Giron, Maria Cecilia; Németh, Zoltán H; Blandizzi, Corrado; Fornai, Matteo

    2016-01-01

    Introduction: Adenosine monophosphate-activated protein kinase (AMPK), known as an enzymatic complex that regulates the energetic metabolism, is emerging as a pivotal enzyme and enzymatic pathway involved in the regulation of immune homeostatic networks. It is also involved in the molecular mechanis

  5. Chlorine-Induced In Situ Regulation to Synthesize Graphene Frameworks with Large Specific Area for Excellent Supercapacitor Performance.

    Science.gov (United States)

    Zhu, Yanyan; Cui, Huijuan; Meng, Xin; Zheng, Jianfeng; Yang, Pengju; Li, Li; Wang, Zhijian; Jia, Suping; Zhu, Zhenping

    2016-03-01

    Three-dimensional (3D) graphene frameworks are usually limited by a complicated preparation process and a low specific surface area. This paper presents a facile suitable approach to effectively synthesize 3D graphene frameworks (GFs) with large specific surface area (up to 1018 m(2) g(-1)) through quick thermal decomposition from sodium chloroacetate, which are considerably larger than those of sodium acetate reported in our recent study. The chlorine element in sodium chloroacetate may possess a strong capability to induce in situ activation and regulate graphene formation during pyrolysis in one step. These GFs can be applied as excellent electrode materials for supercapacitors and can achieve an enhanced supercapacitor performance with a specific capacitance of 266 F g(-1) at a current density of 0.5 A g(-1).

  6. Review of cellular mechanotransduction

    Science.gov (United States)

    Wang, Ning

    2017-06-01

    Living cells and tissues experience physical forces and chemical stimuli in the human body. The process of converting mechanical forces into biochemical activities and gene expression is mechanochemical transduction or mechanotransduction. Significant advances have been made in understanding mechanotransduction at the cellular and molecular levels over the last two decades. However, major challenges remain in elucidating how a living cell integrates signals from mechanotransduction with chemical signals to regulate gene expression and to generate coherent biological responses in living tissues in physiological conditions and diseases.

  7. Regulation No. 44 of 11 September 1989 on the development of areas affected by migration.

    Science.gov (United States)

    1989-01-01

    Among other things, this Bulgarian Regulation establishes the following measures to aid the development of districts affected by migration: 1) local councils shall lease municipal land, buildings, and other property to newcomers for periods of at least 10 years; after the 10-year period has passed the lessee shall acquire title to the leased land or premises and be exempted from paying a transfer tax; 2) the State Savings Bank shall extend to the people of these districts loans for the construction of houses and farm buildings and reconstruction of living premises, with the state paying the interest on the loans; 3) new residents who have to change professions shall receive monetary benefits for up to 6 months during the time they are changing professions; 4) new residents employed in agriculture shall be exempted from payment of income taxes for 5 years; 5) transportation expenses incurred by new residents and their families during the process of resettlement are to be paid by the state; 6) persons under 35 who have graduated from high school shall be admitted to engineering, agriculture, and economic institutions of higher education without taking an entrance exam, if they agree to return to these districts after graduation and work there for no fewer than 6 years; and 7) retired persons working in these districts shall be entitled to receive full remuneration for their work, as well as full pensions.

  8. Self-regulation of ice flow varies across the ablation area in south-west Greenland

    Science.gov (United States)

    van de Wal, R. S. W.; Smeets, C. J. P. P.; Boot, W.; Stoffelen, M.; van Kampen, R.; Doyle, S. H.; Wilhelms, F.; van den Broeke, M. R.; Reijmer, C. H.; Oerlemans, J.; Hubbard, A.

    2015-04-01

    The concept of a positive feedback between ice flow and enhanced melt rates in a warmer climate fuelled the debate regarding the temporal and spatial controls on seasonal ice acceleration. Here we combine melt, basal water pressure and ice velocity data. Using 20 years of data covering the whole ablation area, we show that there is not a strong positive correlation between annual ice velocities and melt rates. Annual velocities even slightly decreased with increasing melt. Results also indicate that melt variations are most important for velocity variations in the upper ablation zone up to the equilibrium line altitude. During the extreme melt in 2012, a large velocity response near the equilibrium line was observed, highlighting the possibility of meltwater to have an impact even high on the ice sheet. This may lead to an increase of the annual ice velocity in the region above S9 and requires further monitoring.

  9. Intermolecular masking of the HIV-1 Rev NLS by the cellular protein HIC: Novel insights into the regulation of Rev nuclear import.

    LENUS (Irish Health Repository)

    Gu, Lili

    2011-03-14

    Abstract Background The HIV-1 regulatory protein Rev, which is essential for viral replication, mediates the nuclear export of unspliced viral transcripts. Rev nuclear function requires active nucleocytoplasmic shuttling, and Rev nuclear import is mediated by the recognition of its Nuclear Localisation Signal (NLS) by multiple import factors, which include transportin and importin β. However, it remains unclear which nuclear import pathway(s) predominate in vivo, and the cellular environment that modulates Rev nucleocytoplasmic shuttling remains to be characterised. Results In our study, we have identified the cellular protein HIC (Human I-mfa domain-Containing protein) as a novel interactor of HIV-1 Rev. We demonstrate that HIC selectively interferes with Rev NLS interaction with importin β and impedes its nuclear import and function, but does not affect Rev nuclear import mediated by transportin. Hence, the molecular determinants mediating Rev-NLS recognition by importin β and transportin appear to be distinct. Furthermore, we have employed HIC and M9 M, a peptide specifically designed to inhibit the transportin-mediated nuclear import pathway, to characterise Rev nuclear import pathways within different cellular environments. Remarkably, we could show that in 293T, HeLa, COS7, Jurkat, U937, THP-1 and CEM cells, Rev nuclear import is cell type specific and alternatively mediated by transportin or importin β, in a mutually exclusive fashion. Conclusions Rev cytoplasmic sequestration by HIC may represent a novel mechanism for the control of Rev function. These studies highlight that the multivalent nature of the Rev NLS for different import receptors enables Rev to adapt its nuclear trafficking strategy.

  10. Intermolecular masking of the HIV-1 Rev NLS by the cellular protein HIC: Novel insights into the regulation of Rev nuclear import

    Directory of Open Access Journals (Sweden)

    Sheehy Noreen

    2011-03-01

    Full Text Available Abstract Background The HIV-1 regulatory protein Rev, which is essential for viral replication, mediates the nuclear export of unspliced viral transcripts. Rev nuclear function requires active nucleocytoplasmic shuttling, and Rev nuclear import is mediated by the recognition of its Nuclear Localisation Signal (NLS by multiple import factors, which include transportin and importin β. However, it remains unclear which nuclear import pathway(s predominate in vivo, and the cellular environment that modulates Rev nucleocytoplasmic shuttling remains to be characterised. Results In our study, we have identified the cellular protein HIC (Human I-mfa domain-Containing protein as a novel interactor of HIV-1 Rev. We demonstrate that HIC selectively interferes with Rev NLS interaction with importin β and impedes its nuclear import and function, but does not affect Rev nuclear import mediated by transportin. Hence, the molecular determinants mediating Rev-NLS recognition by importin β and transportin appear to be distinct. Furthermore, we have employed HIC and M9 M, a peptide specifically designed to inhibit the transportin-mediated nuclear import pathway, to characterise Rev nuclear import pathways within different cellular environments. Remarkably, we could show that in 293T, HeLa, COS7, Jurkat, U937, THP-1 and CEM cells, Rev nuclear import is cell type specific and alternatively mediated by transportin or importin β, in a mutually exclusive fashion. Conclusions Rev cytoplasmic sequestration by HIC may represent a novel mechanism for the control of Rev function. These studies highlight that the multivalent nature of the Rev NLS for different import receptors enables Rev to adapt its nuclear trafficking strategy.

  11. Both viral E2 protein and the cellular factor PEBP2 regulate transcription via E2 consensus sites within the bovine papillomavirus type 4 long control region.

    OpenAIRE

    Jackson, M E; Campo, M S

    1995-01-01

    The bovine papillomavirus type 4 (BPV4) long control region (LCR) contains three consensus binding sites, E2(1), E2(2), and E2(3) (ACCN6GGT), for the viral E2 transcription factor and a fourth degenerate site, dE2 (ATCN6GGT), which lies 3 bp upstream of E2(3). The E2(2) site was found to bind the cellular transcription factor PEBP2, and mutations at this site reduced basal promoter activity by as much as 60%, indicating an important role for PEBP2 in LCR function. Mutation of the E2(3) or dE2...

  12. A cellular stress response (CSR) that interacts with NADPH-P450 reductase (NPR) is a new regulator of hypoxic response.

    Science.gov (United States)

    Oguro, Ami; Koyama, Chika; Xu, Jing; Imaoka, Susumu

    2014-02-28

    NADPH-P450 reductase (NPR) was previously found to contribute to the hypoxic response of cells, but the mechanism was not clarified. In this study, we identified a cellular stress response (CSR) as a new factor interacting with NPR by a yeast two-hybrid system. Overexpression of CSR enhanced the induction of erythropoietin and hypoxia response element (HRE) activity under hypoxia in human hepatocarcinoma cell lines (Hep3B), while knockdown of CSR suppressed them. This new finding regarding the interaction of NPR with CSR provides insight into the function of NPR in hypoxic response.

  13. [Clinical research of electroacupuncture at acupoints of qijie area combined with spine balance-regulating massage on posterior circulation ischemia].

    Science.gov (United States)

    Yang, Jun-xiong; Jing, Li-jun; Yu, Jian-chun; Han, Jing-xian

    2014-09-01

    To compare the clinical efficacy difference between electroacupuncture (EA) at qijie area combined with spine balance-regulating massage and medication for posterior circulation ischemia (PCI). One hundred cases of PCI were randomly divided into a treatment group (50 cases) and a medication group (50 cases). The treatment group was treated with EA at Baihui (GV 20), Sishencong (EX-HN 1), Fengchi (GB 20), Shenshu (BL 23), Danzhong (CV 17), etc. in qijie area combined with spine muscle-relieving massage and comprehensive chiropractic. The medication group was treated with oral administration of nimodipine (30 mg per time, three treatments per day) and vinpocetine injection with 500 mL of glucose injection or intravenous drip of 500 mL 0.9% sodium chloride injection, once a day. Ten treatments were taken as one course in both groups, and two courses were given. The symptom score, mean resistance index (RI) of vertebral artery (VA) and basilar artery (BA), mean velocity of blood flow (Vm) and comprehensive clinical efficacy were compared before and after treatment in two groups. The cured and markedly effective rate was 79.6% (39/49) in the treatment group, which was superior to 54.7% (23/42) in the medication group (Pspine balance-regulating massage has superior effect on improving mean velocity of blood flow and resistance index of vertebral artery and basilar artery as well as symptom score to medication, and is believed to be a safe and effective treatment for posterior circulation ischemia.

  14. Area-specific development of distinct projection neuron subclasses is regulated by postnatal epigenetic modifications.

    Science.gov (United States)

    Harb, Kawssar; Magrinelli, Elia; Nicolas, Céline S; Lukianets, Nikita; Frangeul, Laura; Pietri, Mariel; Sun, Tao; Sandoz, Guillaume; Grammont, Franck; Jabaudon, Denis; Studer, Michele; Alfano, Christian

    2016-01-27

    During cortical development, the identity of major classes of long-distance projection neurons is established by the expression of molecular determinants, which become gradually restricted and mutually exclusive. However, the mechanisms by which projection neurons acquire their final properties during postnatal stages are still poorly understood. In this study, we show that the number of neurons co-expressing Ctip2 and Satb2, respectively involved in the early specification of subcerebral and callosal projection neurons, progressively increases after birth in the somatosensory cortex. Ctip2/Satb2 postnatal co-localization defines two distinct neuronal subclasses projecting either to the contralateral cortex or to the brainstem suggesting that Ctip2/Satb2 co-expression may refine their properties rather than determine their identity. Gain- and loss-of-function approaches reveal that the transcriptional adaptor Lmo4 drives this maturation program through modulation of epigenetic mechanisms in a time- and area-specific manner, thereby indicating that a previously unknown genetic program postnatally promotes the acquisition of final subtype-specific features.

  15. The influence of Maloprim chemoprophylaxis on cellular and humoral immune responses to Plasmodium falciparum asexual blood stage antigens in schoolchildren living in a malaria endemic area of Mozambique

    DEFF Research Database (Denmark)

    Hogh, B; Thompson, R; Lobo, V;

    1994-01-01

    antigens. The study was carried out in the Escola Primária de Lingamo, a primary school in a suburban area of Maputo, Mozambique. A cohort of 392 schoolchildren (aged 7-12 years) was randomly allocated to two equal groups, one receiving chemoprophylaxis with dapsone/pyrimethamine (Maloprim), the other...... assays in vitro. Anti-GLURP and anti-Pf155/RESA antibodies were detected by enzyme-linked immunosorbent assay (ELISA) and erythrocyte membrane immunofluorescence (EMIF), and total anti-P. falciparum antibodies were measured by indirect fluorescent antibody test (IFAT). Immunological reactivities were...

  16. Engineering Cellular Metabolism.

    Science.gov (United States)

    Nielsen, Jens; Keasling, Jay D

    2016-03-10

    Metabolic engineering is the science of rewiring the metabolism of cells to enhance production of native metabolites or to endow cells with the ability to produce new products. The potential applications of such efforts are wide ranging, including the generation of fuels, chemicals, foods, feeds, and pharmaceuticals. However, making cells into efficient factories is challenging because cells have evolved robust metabolic networks with hard-wired, tightly regulated lines of communication between molecular pathways that resist efforts to divert resources. Here, we will review the current status and challenges of metabolic engineering and will discuss how new technologies can enable metabolic engineering to be scaled up to the industrial level, either by cutting off the lines of control for endogenous metabolism or by infiltrating the system with disruptive, heterologous pathways that overcome cellular regulation.

  17. 5G Ultra-Dense Cellular Networks

    OpenAIRE

    Ge, Xiaohu; Tu, Song; Mao, Guoqiang; Wang, Cheng-xiang; Han, Tao

    2015-01-01

    Traditional ultra-dense wireless networks are recommended as a complement for cellular networks and are deployed in partial areas, such as hotspot and indoor scenarios. Based on the massive multiple-input multi-output (MIMO) antennas and the millimeter wavecommunication technologies, the 5G ultra-dense cellular network is proposed to deploy in overall cellular scenarios. Moreover, a distribution network architecture is presented for 5G ultra-dense cellular networks. Furthermore, the backhaul ...

  18. Compliance of the Savannah River Site D-Area cooling system with environmental regulations

    Energy Technology Data Exchange (ETDEWEB)

    Specht, W.L.; Mackey, H.E.; Paller, M.H.; Wike, L.D.; Wilde, E.W. (eds.)

    1990-08-01

    This document presents information relating to a demonstration under Section 316(a) of the Clean Water Act for the 400-D Area cooling system at the Savannah River Site (SRS) near Aiken, South Carolina. The demonstration was mandated because the National Pollution Discharge Elimination System (NPDES) permit for SRS (SC0000175), granted on January 1, 1984, specified in-stream temperature limits in SRS streams of 32.2{degree}C and a {Delta}T limit of 2.8{degree}C above ambient. To achieve compliance with in-stream temperature limits, the Department of Energy (DOE) and the South Carolina Department of Health and Environmental Control (SCDHEC) entered into a Consent Order (84-4-W) which temporarily superseded the temperature requirements and identified a process for attaining compliance. The preferred option for achieving thermal compliance in Beaver Dam Creek consisted of increased flow, with mixing of the raw water basin overflow with the cooling water discharge during the summer months. Although this action can achieve instream temperatures of less than 32.2{degree}C, {Delta}T's still exceed 2.8{degree}C. Therefore, a 316 (a) Demonstration was initiated to determine whether a balanced indigenous biological community can be supported in the receiving stream with {Delta}T's in excess of 2.8{degree}C. A Biological Monitoring Program for Beaver Dam Creek was approved by SCDHEC in June 1988 and implemented in September 1988. The program monitored the water quality, habitat formers, zooplankton, macroinvertebrates, fish, other vertebrate wildlife and threatened and endangered species in Beaver Dam Creek for an 18-month period (September 1988-February 1990). This document summarizes information collected during the monitoring program and evaluates the data to determine whether Beaver Dam Creek presently supports a balanced indigenous biological community. 97 refs., 32 figs., 51 tabs.

  19. Cellular Immune Responses to Live Attenuated Japanese Encephalitis (JE Vaccine SA14-14-2 in Adults in a JE/Dengue Co-Endemic Area.

    Directory of Open Access Journals (Sweden)

    Lance Turtle

    2017-01-01

    Full Text Available Japanese encephalitis (JE virus (JEV causes severe epidemic encephalitis across Asia, for which the live attenuated vaccine SA14-14-2 is being used increasingly. JEV is a flavivirus, and is closely related to dengue virus (DENV, which is co-endemic in many parts of Asia, with clinically relevant interactions. There is no information on the human T cell response to SA14-14-2, or whether responses to SA14-14-2 cross-react with DENV. We used live attenuated JE vaccine SA14-14-2 as a model for studying T cell responses to JEV infection in adults, and to determine whether these T cell responses are cross-reactive with DENV, and other flaviviruses.We conducted a single arm, open label clinical trial (registration: clinicaltrials.gov NCT01656200 to study T cell responses to SA14-14-2 in adults in South India, an area endemic for JE and dengue.Ten out of 16 (62.5% participants seroconverted to JEV SA14-14-2, and geometric mean neutralising antibody (NAb titre was 18.5. Proliferation responses were commonly present before vaccination in the absence of NAb, indicating a likely high degree of previous flavivirus exposure. Thirteen of 15 (87% participants made T cell interferon-gamma (IFNγ responses against JEV proteins. In four subjects tested, at least some T cell epitopes mapped cross-reacted with DENV and other flaviviruses.JEV SA14-14-2 was more immunogenic for T cell IFNγ than for NAb in adults in this JE/DENV co-endemic area. The proliferation positive, NAb negative combination may represent a new marker of long term immunity/exposure to JE. T cell responses can cross-react between JE vaccine and DENV in a co-endemic area, illustrating a need for greater knowledge on such responses to inform the development of next-generation vaccines effective against both diseases.clinicaltrials.gov (NCT01656200.

  20. Cellular Immune Responses to Live Attenuated Japanese Encephalitis (JE) Vaccine SA14-14-2 in Adults in a JE/Dengue Co-Endemic Area.

    Science.gov (United States)

    Turtle, Lance; Tatullo, Filippo; Bali, Tanushka; Ravi, Vasanthapuram; Soni, Mohammed; Chan, Sajesh; Chib, Savita; Venkataswamy, Manjunatha M; Fadnis, Prachi; Yaïch, Mansour; Fernandez, Stefan; Klenerman, Paul; Satchidanandam, Vijaya; Solomon, Tom

    2017-01-01

    Japanese encephalitis (JE) virus (JEV) causes severe epidemic encephalitis across Asia, for which the live attenuated vaccine SA14-14-2 is being used increasingly. JEV is a flavivirus, and is closely related to dengue virus (DENV), which is co-endemic in many parts of Asia, with clinically relevant interactions. There is no information on the human T cell response to SA14-14-2, or whether responses to SA14-14-2 cross-react with DENV. We used live attenuated JE vaccine SA14-14-2 as a model for studying T cell responses to JEV infection in adults, and to determine whether these T cell responses are cross-reactive with DENV, and other flaviviruses. We conducted a single arm, open label clinical trial (registration: clinicaltrials.gov NCT01656200) to study T cell responses to SA14-14-2 in adults in South India, an area endemic for JE and dengue. Ten out of 16 (62.5%) participants seroconverted to JEV SA14-14-2, and geometric mean neutralising antibody (NAb) titre was 18.5. Proliferation responses were commonly present before vaccination in the absence of NAb, indicating a likely high degree of previous flavivirus exposure. Thirteen of 15 (87%) participants made T cell interferon-gamma (IFNγ) responses against JEV proteins. In four subjects tested, at least some T cell epitopes mapped cross-reacted with DENV and other flaviviruses. JEV SA14-14-2 was more immunogenic for T cell IFNγ than for NAb in adults in this JE/DENV co-endemic area. The proliferation positive, NAb negative combination may represent a new marker of long term immunity/exposure to JE. T cell responses can cross-react between JE vaccine and DENV in a co-endemic area, illustrating a need for greater knowledge on such responses to inform the development of next-generation vaccines effective against both diseases. clinicaltrials.gov (NCT01656200).

  1. Cellular Immune Responses to Live Attenuated Japanese Encephalitis (JE) Vaccine SA14-14-2 in Adults in a JE/Dengue Co-Endemic Area

    Science.gov (United States)

    Tatullo, Filippo; Bali, Tanushka; Ravi, Vasanthapuram; Soni, Mohammed; Chan, Sajesh; Chib, Savita; Venkataswamy, Manjunatha M.; Fadnis, Prachi; Yaïch, Mansour; Fernandez, Stefan; Klenerman, Paul; Satchidanandam, Vijaya; Solomon, Tom

    2017-01-01

    Background Japanese encephalitis (JE) virus (JEV) causes severe epidemic encephalitis across Asia, for which the live attenuated vaccine SA14-14-2 is being used increasingly. JEV is a flavivirus, and is closely related to dengue virus (DENV), which is co-endemic in many parts of Asia, with clinically relevant interactions. There is no information on the human T cell response to SA14-14-2, or whether responses to SA14-14-2 cross-react with DENV. We used live attenuated JE vaccine SA14-14-2 as a model for studying T cell responses to JEV infection in adults, and to determine whether these T cell responses are cross-reactive with DENV, and other flaviviruses. Methods We conducted a single arm, open label clinical trial (registration: clinicaltrials.gov NCT01656200) to study T cell responses to SA14-14-2 in adults in South India, an area endemic for JE and dengue. Results Ten out of 16 (62.5%) participants seroconverted to JEV SA14-14-2, and geometric mean neutralising antibody (NAb) titre was 18.5. Proliferation responses were commonly present before vaccination in the absence of NAb, indicating a likely high degree of previous flavivirus exposure. Thirteen of 15 (87%) participants made T cell interferon-gamma (IFNγ) responses against JEV proteins. In four subjects tested, at least some T cell epitopes mapped cross-reacted with DENV and other flaviviruses. Conclusions JEV SA14-14-2 was more immunogenic for T cell IFNγ than for NAb in adults in this JE/DENV co-endemic area. The proliferation positive, NAb negative combination may represent a new marker of long term immunity/exposure to JE. T cell responses can cross-react between JE vaccine and DENV in a co-endemic area, illustrating a need for greater knowledge on such responses to inform the development of next-generation vaccines effective against both diseases. Trial Registration clinicaltrials.gov (NCT01656200) PMID:28135273

  2. Comprehensive Small RNA-Seq of Adeno-Associated Virus (AAV)-Infected Human Cells Detects Patterns of Novel, Non-Coding AAV RNAs in the Absence of Cellular miRNA Regulation

    Science.gov (United States)

    Stutika, Catrin; Mietzsch, Mario; Gogol-Döring, Andreas; Weger, Stefan; Sohn, Madlen; Chen, Wei; Heilbronn, Regine

    2016-01-01

    Most DNA viruses express small regulatory RNAs, which interfere with viral or cellular gene expression. For adeno-associated virus (AAV), a small ssDNA virus with a complex biphasic life cycle miRNAs or other small regulatory RNAs have not yet been described. This is the first comprehensive Illumina-based RNA-Seq analysis of small RNAs expressed by AAV alone or upon co-infection with helper adenovirus or HSV. Several hotspots of AAV-specific small RNAs were detected mostly close to or within the AAV-ITR and apparently transcribed from the newly identified anti-p5 promoter. An additional small RNA hotspot was located downstream of the p40 promoter, from where transcription of non-coding RNAs associated with the inhibition of adenovirus replication were recently described. Parallel detection of known Ad and HSV miRNAs indirectly validated the newly identified small AAV RNA species. The predominant small RNAs were analyzed on Northern blots and by human argonaute protein-mediated co-immunoprecipitation. None of the small AAV RNAs showed characteristics of bona fide miRNAs, but characteristics of alternative RNA processing indicative of differentially regulated AAV promoter-associated small RNAs. Furthermore, the AAV-induced regulation of cellular miRNA levels was analyzed at different time points post infection. In contrast to other virus groups AAV infection had virtually no effect on the expression of cellular miRNA, which underscores the long-established concept that wild-type AAV infection is apathogenic. PMID:27611072

  3. Stochastic Nature in Cellular Processes

    Institute of Scientific and Technical Information of China (English)

    刘波; 刘圣君; 王祺; 晏世伟; 耿轶钊; SAKATA Fumihiko; GAO Xing-Fa

    2011-01-01

    The importance of stochasticity in cellular processes is increasingly recognized in both theoretical and experimental studies. General features of stochasticity in gene regulation and expression are briefly reviewed in this article, which include the main experimental phenomena, classification, quantization and regulation of noises. The correlation and transmission of noise in cascade networks are analyzed further and the stochastic simulation methods that can capture effects of intrinsic and extrinsic noise are described.

  4. BubR1 Acts as a Promoter in Cellular Motility of Human Oral Squamous Cancer Cells through Regulating MMP-2 and MMP-9

    Directory of Open Access Journals (Sweden)

    Chou-Kit Chou

    2015-07-01

    Full Text Available BubR1 is a critical component of spindle assembly checkpoint, ensuring proper chromatin segregation during mitosis. Recent studies showed that BubR1 was overexpressed in many cancer cells, including oral squamous cell carcinomas (OSCC. However, the effect of BubR1 on metastasis of OSCC remains unclear. This study aimed to unravel the role of BubR1 in the progression of OSCC and confirm the expression of BubR1 in a panel of malignant OSCC cell lines with different invasive abilities. The results of quantitative real-time PCR showed that the mRNA level of BubR1 was markedly increased in four OSCC cell lines, Ca9-22, HSC3, SCC9 and Cal-27 cells, compared to two normal cells, normal human oral keratinocytes (HOK and human gingival fibroblasts (HGF. Moreover, the expression of BubR1 in these four OSCC cell lines was positively correlated with their motility. Immunofluorescence revealed that BubR1 was mostly localized in the cytosol of human gingival carcinoma Ca9-22 cells. BubR1 knockdown significantly decreased cellular invasion but slightly affect cellular proliferation on both Ca9-22 and Cal-27 cells. Consistently, the activities of metastasis-associated metalloproteinases MMP-2 and MMP-9 were attenuated in BubR1 knockdown Ca9-22 cells, suggesting the role of BubR1 in promotion of OSCC migration. Our present study defines an alternative pathway in promoting metastasis of OSCC cells, and the expression of BubR1 could be a prognostic index in OSCC patients.

  5. Down-regulation of pancreatic and duodenal homeobox-1 by somatostatin receptor subtype 5: a novel mechanism for inhibition of cellular proliferation and insulin secretion by somatostatin

    Directory of Open Access Journals (Sweden)

    Charles eBrunicardi

    2014-06-01

    Full Text Available Somatostatin is a regulatory peptide and acts as an endogenous inhibitory regulator of the secretory and proliferative responses of target cells. Somatostatin’s actions are mediated by a family of seven transmembrane domain G protein-coupled receptors that comprise five distinct subtypes (SSTR1-5. SSTR5 is one of the major SSTRs in the islets of Langerhans. Homeodomain-containing transcription factor pancreatic and duodenal homeobox-1 (PDX-1 is essential for pancreatic development, β cell differentiation, maintenance of normal β cell functions in adults and tumorigenesis. Recent studies show that SSTR5 acts as a negative regulator for PDX-1 expression and that SSTR5 mediates somatostatin’s inhibitory effect on cell proliferation and insulin expression/excretion through down-regulating PDX-1 expression. SSTR5 exerts its inhibitory effect on PDX-1 expression at both the transcriptional level by down-regulating PDX-1 mRNA and the post-translational level by enhancing PDX-1 ubiquitination. Identification of PDX-1 as a transcriptional target for SSTR5 may help in guiding the choice of therapeutic cancer treatments.

  6. Cocaine- and amphetamine-regulated transcript (CART) peptide immunoreactivity in feeding- and reward-related brain areas of young OLETF rats.

    NARCIS (Netherlands)

    Armbruszt, S.; Abraham, H.; Figler, M.; Kozicz, T.L.; Hajnal, A.

    2013-01-01

    Cocaine- and amphetamine-regulated transcript (CART) peptide is expressed in brain areas involved in the control of appetite, drug reward and homeostatic regulation and it has an overall anorexigenic effect. Recently, we have shown that CART peptide immunoreactivity was significantly reduced in the

  7. HDACi: cellular effects, opportunities for restorative dentistry.

    LENUS (Irish Health Repository)

    Duncan, H F

    2011-12-01

    Acetylation of histone and non-histone proteins alters gene expression and induces a host of cellular effects. The acetylation process is homeostatically balanced by two groups of cellular enzymes, histone acetyltransferases (HATs) and histone deacetylases (HDACs). HAT activity relaxes the structure of the human chromatin, rendering it transcriptionally active, thereby increasing gene expression. In contrast, HDAC activity leads to gene silencing. The enzymatic balance can be \\'tipped\\' by histone deacetylase inhibitors (HDACi), leading to an accumulation of acetylated proteins, which subsequently modify cellular processes including stem cell differentiation, cell cycle, apoptosis, gene expression, and angiogenesis. There is a variety of natural and synthetic HDACi available, and their pleiotropic effects have contributed to diverse clinical applications, not only in cancer but also in non-cancer areas, such as chronic inflammatory disease, bone engineering, and neurodegenerative disease. Indeed, it appears that HDACi-modulated effects may differ between \\'normal\\' and transformed cells, particularly with regard to reactive oxygen species accumulation, apoptosis, proliferation, and cell cycle arrest. The potential beneficial effects of HDACi for health, resulting from their ability to regulate global gene expression by epigenetic modification of DNA-associated proteins, also offer potential for application within restorative dentistry, where they may promote dental tissue regeneration following pulpal damage.

  8. Cellular senescence and autophagy of myoepithelial cells are involved in the progression of in situ areas of carcinoma ex-pleomorphic adenoma to invasive carcinoma. An in vitro model.

    Science.gov (United States)

    Silva, Carolina Amália Barcellos; Martinez, Elizabeth Ferreira; Demasi, Ana Paula Dias; Altemani, Albina; da Silveira Bossonaro, Jeruza Pinheiro; Araújo, Ney Soares; de Araújo, Vera Cavalcanti

    2015-09-01

    During tumor invasion, benign myoepithelial cells of carcinoma ex-pleomorphic adenoma (CXPA) surround malignant epithelial cells and disappear. The mechanisms involved in the death and disappearance of these myoepithelial cells were investigated via analysis of the expression of regulatory proteins for apoptosis, autophagy and cellular senescence in an in situ in vitro model. Protein expression relating to apoptosis (Bax, Bcl-2, Survivin), autophagy (Beclin-1, LC3B) and cellular senescence (p21, p16) was evaluated using indirect immunofluorescence. β-galactosidase expression was assessed via histochemistry. Biopsies of CXPA (ex vivo) allowed immunhistochemical evaluation of p21 and p16, whilst LC3B, p21 and p16 protein expression was analyzed by western blotting. In the in vitro model, the myoepithelial cells were positive for LC3B (cytoplasm) and p21 (nucleus), whilst in vivo positivity for p21 and p16 was observed. In vitro, β-galactosidase activity increased in the myoepithelial cells over time. Western blotting analysis revealed an increased LC3B, p16 and p21 expression in the myoepithelial cells with previous contact with the malignant cells when compared with those without contact. The investigation of behavior of benign myoepithelial cells in ductal areas of CXAP revealed that the myoepithelial cells are involved in the autophagy-senescence phenotype that subsequently leads to their disappearance.

  9. Environment Aware Cellular Networks

    KAUST Repository

    Ghazzai, Hakim

    2015-02-01

    The unprecedented rise of mobile user demand over the years have led to an enormous growth of the energy consumption of wireless networks as well as the greenhouse gas emissions which are estimated currently to be around 70 million tons per year. This significant growth of energy consumption impels network companies to pay huge bills which represent around half of their operating expenditures. Therefore, many service providers, including mobile operators, are looking for new and modern green solutions to help reduce their expenses as well as the level of their CO2 emissions. Base stations are the most power greedy element in cellular networks: they drain around 80% of the total network energy consumption even during low traffic periods. Thus, there is a growing need to develop more energy-efficient techniques to enhance the green performance of future 4G/5G cellular networks. Due to the problem of traffic load fluctuations in cellular networks during different periods of the day and between different areas (shopping or business districts and residential areas), the base station sleeping strategy has been one of the main popular research topics in green communications. In this presentation, we present several practical green techniques that provide significant gains for mobile operators. Indeed, combined with the base station sleeping strategy, these techniques achieve not only a minimization of the fossil fuel consumption but also an enhancement of mobile operator profits. We start with an optimized cell planning method that considers varying spatial and temporal user densities. We then use the optimal transport theory in order to define the cell boundaries such that the network total transmit power is reduced. Afterwards, we exploit the features of the modern electrical grid, the smart grid, as a new tool of power management for cellular networks and we optimize the energy procurement from multiple energy retailers characterized by different prices and pollutant

  10. Serotonin-3 Receptors in the Posterior Ventral Tegmental Area Regulate Ethanol Self-Administration of Alcohol-Preferring (P) Rats

    Science.gov (United States)

    Rodd, Zachary A.; Bell, Richard L.; Oster, Scott M.; Toalston, Jamie E.; Pommer, Tylene J.; McBride, William J.; Murphy, James M.

    2015-01-01

    Several studies indicated the involvement of serotonin-3 (5-HT3) receptors in regulating alcohol-drinking behavior. The objective of this study was to determine the involvement of 5-HT3 receptors within the ventral tegmental area (VTA) in regulating ethanol self-administration by alcohol-preferring (P) rats. Standard two-lever operant chambers were used to examine the effects of 7 consecutive bilateral micro-infusions of ICS205-930 (ICS), a 5-HT3 receptor antagonist, directly into the posterior VTA on the acquisition and maintenance of 15% (v/v) ethanol self-administration. P rats readily acquired ethanol self-administration by the 4th session. The three highest doses (0.125, 0.25 and 1.25 ug) of ICS prevented acquisition of ethanol self-administration. During the acquisition post-injection period, all rats treated with ICS demonstrated higher responding on the ethanol lever, with the highest dose producing the greatest effect. In contrast, during the maintenance phase, the 3 highest doses (0.75, 1.0 and 1.25 ug) of ICS significantly increased responding on the ethanol lever; following the 7-day dosing regimen, responding on the ethanol lever returned to control levels. Micro-infusion of ICS into the posterior VTA did not alter the low responding on the water lever, and did not alter saccharin (0.0125% w/v) self-administration.. Micro-infusion of ICS into the anterior VTA did not alter ethanol self-administration. Overall, the results of this study suggest that 5-HT3 receptors in the posterior VTA of the P rat may be involved in regulating ethanol self-administration. In addition, chronic operant ethanol self-administration, and/or repeated treatments with a 5-HT3 receptor antagonist may alter neuronal circuitry within the posterior VTA. PMID:20682192

  11. Plasma membrane Ca2+-ATPase isoforms composition regulates cellular pH homeostasis in differentiating PC12 cells in a manner dependent on cytosolic Ca2+ elevations

    DEFF Research Database (Denmark)

    Boczek, Tomasz; Lisek, Malwina; Ferenc, Bozena

    2014-01-01

    Plasma membrane Ca2+-ATPase (PMCA) by extruding Ca2+ outside the cell, actively participates in the regulation of intracellular Ca2+ concentration. Acting as Ca2+/H+ counter-transporter, PMCA transports large quantities of protons which may affect organellar pH homeostasis. PMCA exists in four....... In steady-state conditions, higher TMRE uptake in PMCA2-knockdown line was driven by plasma membrane potential (Ψp). Nonetheless, mitochondrial membrane potential (Ψm) in this line was dissipated during Ca2+ overload. Cyclosporin and bongkrekic acid prevented Ψm loss suggesting the involvement of Ca2...... isoforms (PMCA1-4) but only PMCA2 and PMCA3, due to their unique localization and features, perform more specialized function. Using differentiated PC12 cells we assessed the role of PMCA2 and PMCA3 in the regulation of intracellular pH in steady-state conditions and during Ca2+ overload evoked by 59 m...

  12. The human angiotensin AT(1) receptor supports G protein-independent extracellular signal-regulated kinase 1/2 activation and cellular proliferation

    DEFF Research Database (Denmark)

    Hansen, Jakob Lerche; Aplin, Mark; Hansen, Jonas Tind;

    2008-01-01

    The angiotensin AT(1) receptor is a key regulator of blood pressure and body fluid homeostasis, and it plays a key role in the pathophysiology of several cardiovascular diseases such as hypertension, cardiac hypertrophy, congestive heart failure, and arrhythmia. The importance of human angiotensi...... by the human angiotensin AT(1) receptor has clear pharmacological implications for development of drugs with pathway-specific actions and defined biological outcomes....

  13. Lesion simulating disease1, enhanced disease susceptibility1, and phytoalexin deficient4 conditionally regulate cellular signaling homeostasis, photosynthesis, water use efficiency, and seed yield in Arabidopsis.

    Science.gov (United States)

    Wituszynska, Weronika; Slesak, Ireneusz; Vanderauwera, Sandy; Szechynska-Hebda, Magdalena; Kornas, Andrzej; Van Der Kelen, Katrien; Mühlenbock, Per; Karpinska, Barbara; Mackowski, Sebastian; Van Breusegem, Frank; Karpinski, Stanislaw

    2013-04-01

    There is growing evidence that for a comprehensive insight into the function of plant genes, it is crucial to assess their functionalities under a wide range of conditions. In this study, we examined the role of lesion simulating disease1 (LSD1), enhanced disease susceptibility1 (EDS1), and phytoalexin deficient4 (PAD4) in the regulation of photosynthesis, water use efficiency, reactive oxygen species/hormonal homeostasis, and seed yield in Arabidopsis (Arabidopsis thaliana) grown in the laboratory and in the field. We demonstrate that the LSD1 null mutant (lsd1), which is known to exhibit a runaway cell death in nonpermissive conditions, proves to be more tolerant to combined drought and high-light stress than the wild type. Moreover, depending on growing conditions, it shows variations in water use efficiency, salicylic acid and hydrogen peroxide concentrations, photosystem II maximum efficiency, and transcription profiles. However, despite these changes, lsd1 demonstrates similar seed yield under all tested conditions. All of these traits depend on EDS1 and PAD4. The differences in the pathways prevailing in the lsd1 in various growing environments are manifested by the significantly smaller number of transcripts deregulated in the field compared with the laboratory, with only 43 commonly regulated genes. Our data indicate that LSD1, EDS1, and PAD4 participate in the regulation of various molecular and physiological processes that influence Arabidopsis fitness. On the basis of these results, we emphasize that the function of such important regulators as LSD1, EDS1, and PAD4 should be studied not only under stable laboratory conditions, but also in the environment abounding in multiple stresses.

  14. Iron Oxide Nanoparticles Stimulates Extra-Cellular Matrix Production in Cellular Spheroids

    Directory of Open Access Journals (Sweden)

    Megan Casco

    2017-01-01

    Full Text Available Nanotechnologies have been integrated into drug delivery, and non-invasive imaging applications, into nanostructured scaffolds for the manipulation of cells. The objective of this work was to determine how the physico-chemical properties of magnetic nanoparticles (MNPs and their spatial distribution into cellular spheroids stimulated cells to produce an extracellular matrix (ECM. The MNP concentration (0.03 mg/mL, 0.1 mg/mL and 0.3 mg/mL, type (magnetoferritin, shape (nanorod—85 nm × 425 nm and incorporation method were studied to determine each of their effects on the specific stimulation of four ECM proteins (collagen I, collagen IV, elastin and fibronectin in primary rat aortic smooth muscle cell. Results demonstrated that as MNP concentration increased there was up to a 6.32-fold increase in collagen production over no MNP samples. Semi-quantitative Immunohistochemistry (IHC results demonstrated that MNP type had the greatest influence on elastin production with a 56.28% positive area stain compared to controls and MNP shape favored elastin stimulation with a 50.19% positive area stain. Finally, there are no adverse effects of MNPs on cellular contractile ability. This study provides insight on the stimulation of ECM production in cells and tissues, which is important because it plays a critical role in regulating cellular functions.

  15. Regulation of platelet-activating factor (PAF) receptor and PAF receptor-mediated cellular response in Kupffer cells: Effect of vanadate

    Energy Technology Data Exchange (ETDEWEB)

    Chao, W.; Liu, H.; Hanahan, D.J.; Olson, M.S. (Univ. of Texas, San Antonio (United States))

    1991-03-11

    Vanadate is a phosphate analogue which affects phosphate transfer reactions which may be involved in regulatory processes in which tyrosine phosphorylation or dephosphorylation may be an important component. In the present study vanadate decreased the surface expression of PAF receptors and caused tyrosine-phosphorylation in numerous proteins in intact Kupffer cells. The vanadate-induced tyrosine-phosphorylation was inhibited by genistein, a specific tyrosine kinase inhibitor. The EC{sub 50} for the vanadate-initiated decrease in the surface expression of PAF receptors was approximately 0.25 mM, 0.65 mM, and 2 mM, respectively, when the vanadate exposure time was 3 h, 2h, and 1h. As a consequence, PAF-stimulated prostaglandin E{sub 2} (PGE{sub 2}) formation was attenuated in vanadate-treated Kupffer cells. While vanadate itself was found to stimulate PGE{sub 2} production, PAF-stimulated PGE{sub 2}formation was inhibited significantly by genistein. The present study suggests that vanadate stimulated strongly tyrosine-phosphorylation of cellular proteins and decreased the surface expression of PAF receptor in intact Kupffer cells.

  16. The β-domain of cluster 2b streptokinase is a major determinant for the regulation of its plasminogen activation activity by cellular plasminogen receptors.

    Science.gov (United States)

    Zhang, Yueling; Mayfield, Jeffrey A; Ploplis, Victoria A; Castellino, Francis J

    2014-02-21

    Cluster 2b streptokinase (SK2b), secreted by invasive skin-trophic strains of Streptococcus pyogenes (GAS), is a human plasminogen (hPg) activator that optimally functions when human plasma hPg is bound, via its kringle-2 domain, to cognizant bacterial cells through the a1a2 domain of the major cellular hPg receptor, Plasminogen-binding group A streptococcal M-like protein (PAM). Another class of streptokinases (SK1), secreted primarily by GAS strains that possess affinity for pharyngeal infections, does not require PAM-bound hPg for optimal activity. We find herein that replacement of the central β-domain of SK2b with the same module from SK1 reduces the dependency of SK2b on PAM, and the converse is true when the β-domain of SK1 is replaced with this same region of SK2b. These data suggest that simple evolutionary shuttling of protein domains in GAS can be employed by GAS to rapidly generate strains that differ in tissue tropism and invasive capability and allow the bacteria to survive different challenges by the host.

  17. Modeling and evaluation of compliance to water quality regulations in bathing areas on the Daoulas catchment and estuary (France).

    Science.gov (United States)

    Bougeard, M; Le Saux, J C; Jouan, M; Durand, G; Pommepuy, M

    2010-01-01

    The microbiological quality of waters in estuaries determines their acceptability for recreational uses. Microbiological contamination often results from urban wastewater discharges or non-point source pollution (manure spreading), and can cause bathing zones to be closed. European regulations (EC/7/2006) have proposed standards (500 E. coli/100 ml) for the acceptability areas for bathing. In this study, two models were associated to simulate contamination: SWAT on a catchment and MARS 2D in the downstream estuary. After river flow calibration and validation, two scenarios were simulated in SWAT, and E. coli fluxes obtained at the main outlet of the catchment were then introduced into MARS 2D to follow E. coli concentrations in the estuary. An annual evaluation of compliance to bathing area water quality standards was then calculated, linked with daily rainfall classes. Water quality in the estuary was below the standard on 13 days, including 5 days with rainfall superior to 10 mm, due to faecal contamination from soil leaching by rain, and 5 days with rainfall ranging from 0.1 to 5 mm/day, due to the high frequency of this level of rainfall. To conclude, this study allowed us to demonstrate the efficiency of models to gain a better understanding on water quality degradation factors.

  18. Cryobehavior of the plasma membrane in protoplasts isolated from cold-acclimated Arabidopsis leaves is related to surface area regulation.

    Science.gov (United States)

    Yamazaki, Tomokazu; Kawamura, Yukio; Uemura, Matsuo

    2008-06-01

    Extracellular freezing in plants results in dehydration and mechanical stresses upon the plasma membrane. Plants that acquire enhanced freezing tolerance after cold acclimation can withstand these two physical stresses. To understand the tolerance to freeze-induced physical stresses, the cryobehavior of the plasma membrane was observed using protoplasts isolated from cold-acclimated Arabidopsis thaliana leaves with the combination of a lipophilic fluorescent dye FM 1-43 and cryomicroscopy. We found that many vesicular structures appeared in the cytoplasmic region near the plasma membrane just after extracellular freezing occurred. These structures, referred to as freeze-induced vesicular structures (FIVs), then developed horizontally near the plasma membrane during freezing. There was a strong correlation between the increase in individual FIV size and the decrease in the surface area of the protoplasts during freezing. Some FIVs fused with their neighbors as the temperature decreased. Occasionally, FIVs fused with the plasma membrane, which may be necessary to relax the stress upon the plasma membrane during freezing. Vesicular structures resembling FIVs were also induced when protoplasts were mechanically pressed between a coverslip and slide glass. Fewer FIVs formed when protoplasts were subjected to hyperosmotic solution, suggesting that FIV formation is associated with mechanical stress rather than dehydration. Collectively, these results suggest that cold-acclimated plant cells may balance membrane tension in the plasma membrane by regulating the surface area. This enables plant cells to withstand the direct mechanical stress imposed by extracellular freezing.

  19. Multiuser Cellular Network

    CERN Document Server

    Bao, Yi; Chen, Ming

    2011-01-01

    Modern radio communication is faced with a problem about how to distribute restricted frequency to users in a certain space. Since our task is to minimize the number of repeaters, a natural idea is enlarging coverage area. However, coverage has restrictions. First, service area has to be divided economically as repeater's coverage is limited. In this paper, our fundamental method is to adopt seamless cellular network division. Second, underlying physics content in frequency distribution problem is interference between two close frequencies. Consequently, we choose a proper frequency width of 0.1MHz and a relevantly reliable setting to apply one frequency several times. We make a few general assumptions to simplify real situation. For instance, immobile users yield to homogenous distribution; repeaters can receive and transmit information in any given frequency in duplex operation; coverage is mainly decided by antenna height. Two models are built up to solve 1000 users and 10000 users situations respectively....

  20. Cell surface area regulation in neurons in hippocampal slice cultures is resistant to oxygen-glucose deprivation

    Directory of Open Access Journals (Sweden)

    Natalya Shulyakova

    2010-09-01

    Full Text Available Natalya Shulyakova1,2, Jamie Fong2, Diana Diec2, Adrian Nahirny1,2, Linda R Mills1,21Department of Physiology, University of Toronto, Toronto, ON, Canada, M5T 2S8; 2Toronto Western Hospital Research Institute, University Health Network, 11-430, 399 Bathurst St, Toronto, ON, Canada, M5T 2S8Background: Neurons swell in response to a variety of insults. The capacity to recover, ie, to shrink, is critical for neuronal function and survival. Studies on dissociated neurons have shown that during swelling and shrinking, neurons reorganize their plasma membrane; as neurons swell, in response to hypo-osmotic media, the bilayer area increases. Upon restoration of normo-osmotic media, neurons shrink, forming transient invaginations of the plasma membrane known as vacuole-like dilations (VLDs, to accommodate the decrease in the bilayer.Methods: Here we used confocal microscopy to monitor neuronal swelling and shrinking in the three-dimensional (3D environment of post-natal rat hippocampal slice cultures. To label neurons, we used biolistic transfection, to introduce enhanced green fluorescent protein (eGFP targeted to the cytoplasm; and a membrane targeted GFP (lckGFP, targeted to the plasma membrane.Results: Neurons in slice cultures swelled and shrank in response to hypo-osmotic to normo-osmotic media changes. Oxygen-glucose deprivation (OGD caused sustained neuronal swelling; after reperfusion, some neurons recovered but in others, VLD recovery was stalled. OGD did not impair neuronal capacity to recover from a subsequent osmotic challenge.Conclusion: These results suggest cell surface area regulation (SAR is an intrinsic property of neurons, and that neuronal capacity for SAR may play an important role in the brain’s response to ischemic insults.Keywords: neurons, swelling, ischemia, cell surface area, hippocampal slice culture

  1. Using NMR to Identify Structural Features of Lin28-Regulated miRNAs and mRNAs and as a Tool for Comparing Differences in Cellular Metabolism

    OpenAIRE

    O'Day, Elizabeth Mary

    2013-01-01

    Part 1 of this thesis seeks to identify shared structural features of Lin28-regulated miRNAs and mRNAs. Lin28 is an evolutionarily conserved, RNA binding protein, highly expressed in stem cells and poorly differentiated cancers, that inhibits differentiation and helps maintain stem cell properties. Lin28 binds to both the loops of let-7 precursors to block let-7 biogenesis and to Lin28 responsive elements (LREs) in mRNAs either to enhance or inhibit translation. Lin28 RNA binding properties a...

  2. E2F1-mediated upregulation of p19INK4d determines its periodic expression during cell cycle and regulates cellular proliferation.

    Directory of Open Access Journals (Sweden)

    Abel L Carcagno

    Full Text Available BACKGROUND: A central aspect of development and disease is the control of cell proliferation through regulation of the mitotic cycle. Cell cycle progression and directionality requires an appropriate balance of positive and negative regulators whose expression must fluctuate in a coordinated manner. p19INK4d, a member of the INK4 family of CDK inhibitors, has a unique feature that distinguishes it from the remaining INK4 and makes it a likely candidate for contributing to the directionality of the cell cycle. p19INK4d mRNA and protein levels accumulate periodically during the cell cycle under normal conditions, a feature reminiscent of cyclins. METHODOLOGY/PRINCIPAL FINDINGS: In this paper, we demonstrate that p19INK4d is transcriptionally regulated by E2F1 through two response elements present in the p19INK4d promoter. Ablation of this regulation reduced p19 levels and restricted its expression during the cell cycle, reflecting the contribution of a transcriptional effect of E2F1 on p19 periodicity. The induction of p19INK4d is delayed during the cell cycle compared to that of cyclin E, temporally separating the induction of these proliferative and antiproliferative target genes. Specific inhibition of the E2F1-p19INK4d pathway using triplex-forming oligonucleotides that block E2F1 binding on p19 promoter, stimulated cell proliferation and increased the fraction of cells in S phase. CONCLUSIONS/SIGNIFICANCE: The results described here support a model of normal cell cycle progression in which, following phosphorylation of pRb, free E2F induces cyclin E, among other target genes. Once cyclinE/CDK2 takes over as the cell cycle driving kinase activity, the induction of p19 mediated by E2F1 leads to inhibition of the CDK4,6-containing complexes, bringing the G1 phase to an end. This regulatory mechanism constitutes a new negative feedback loop that terminates the G1 phase proliferative signal, contributing to the proper coordination of the cell

  3. Multiple cellular roles of Neurospora crassa plc-1, splA2, and cpe-1 in regulation of cytosolic free calcium, carotenoid accumulation, stress responses, and acquisition of thermotolerance.

    Science.gov (United States)

    Barman, Ananya; Tamuli, Ranjan

    2015-04-01

    Phospholipase C1 (PLC1), secretory phospholipase A2 (sPLA2) and Ca(2+)/H(+) exchanger proteins regulate calcium signaling and homeostasis in eukaryotes. In this study, we investigate functions for phospholipase C1 (plc-1), sPLA2 (splA2) and a Ca(2+)/H(+) exchanger (cpe-1) in the filamentous fungus Neurospora crassa. The Δplc-1, ΔsplA2, and Δcpe-1 mutants exhibited a growth defect on medium supplemented with the divalent ionophore A23187, suggesting that these genes might play a role in regulation of cytosolic free Ca(2+) concentration ([Ca(2+)](c)) in N. crassa. The strains lacking plc-1, splA2, and cpe-1 possessed higher carotenoid content than wild type at 8°C, 22°C, and 30°C, and showed increased ultraviolet (UV)-survival under conditions that induced carotenoid accumulation. Moreover, Δplc-1, ΔsplA2, and Δcpe-1 mutants showed reduced survival rate under hydrogen peroxide-induced oxidative stress and induced thermotolerance after exposure to heat shock temperatures. Thus, this study revealed multiple cellular roles for plc-1, splA2, and cpe-1 genes in regulation of [Ca(2+)](c), carotenoid accumulation, survival under stress conditions, and acquisition of thermotolerance induced by heat shock.

  4. Dual Regulation of Cell Death and Cell Survival upon induction of cellular stress by Isopimara-7,15-Dien-19-Oic Acid in cervical cancer, Hela cells In vitro

    Directory of Open Access Journals (Sweden)

    Nadiah eAbu

    2016-03-01

    Full Text Available The fritarillia imperialis is an ornamental flower that can be found in various parts of the world including Iraq, Afghanistan, Pakistan and the Himalayas. The use of this plant as traditional remedy is widely known. This study aims to unveil the anti-cancer potentials of Isopimara-7,15-Dien-19-Oic Acid, extracted from the bulbs of Fritillaria imperialis in cervical cancer cell line, HeLa cells. Flow cytometry analysis of cell death, gene expression analysis via cDNA microarray and protein array were performed. Based on the results, Isopimara-7,15-Dien-19-Oic acid simultaneously induced cell death and promoted cell survival. The execution of apoptosis was apparent based on the flow cytometry results and regulation of both pro and anti-apoptotic genes. Additionally, the regulation of anti-oxidant genes were up-regulated especially thioredoxin, glutathione and superoxide dismutase- related genes. Moreover, the treatment also induced the activation of pro-survival heat shock proteins. Collectively, Isopimara-7,15-Dien-19-Oic Acid managed to induce cellular stress in HeLa cells and activate several anti- and pro survival pathways.

  5. PLP2 of mouse hepatitis virus A59 (MHV-A59 targets TBK1 to negatively regulate cellular type I interferon signaling pathway.

    Directory of Open Access Journals (Sweden)

    Gang Wang

    Full Text Available BACKGROUND: Coronaviruses such as severe acute respiratory syndrome (SARS coronavirus (SCoV and mouse hepatitis virus A59 (MHV-A59 have evolved strategies to disable the innate immune system for productive replication and spread of infection. We have previously shown that papain-like protease domain 2 (PLP2, a catalytic domain of the nonstructural protein 3 (nsp3 of MHV-A59, encodes a deubiquitinase (DUB and inactivates IFN regulatory factor 3 (IRF3 thereby the type I interferon (IFN response. PRINCIPAL FINDINGS: Here we provide further evidence that PLP2 may also target TANK-binding kinase-1 (TBK1, the upstream kinase of IRF3 in the IFN signaling pathway. Overexpression experiments showed that PLP2 deubiquitinated TBK1 and reduced its kinase activity, hence inhibited IFN-β reporter activity. Albeit promiscuous in deubiquitinating cellular proteins, PLP2 inactivated TBK1 and IFN-β response in TNF receptor associated factor 3 (TRAF3 deficient cells, suggesting that targeting TBK1 would be sufficient for PLP2 to inhibit IRF3 activation. This notion was further supported by in vitro kinase assays, in which prior treatment of TBK1 with PLP2 inhibited its kinase activity to phosphorylate IRF3. Intriguing enough, results of PLP2 overexpression system and MHV-A59 infection system proved that PLP2 formed an inactive complex with TBK1 and IRF3 in the cytoplasm and the presence of PLP2 stabilized the hypo-phosphorylated IRF3-TBK1 complex in a dose-dependent manner. CONCLUSIONS: These results suggest that PLP2 not only inactivates TBK1, but also prevents IRF3 nuclear translocation hence inhibits IFN transcription activation. Identification of the conserved DUB activity of PLP2 in suppression of IFN signaling would provide a useful clue to the development of therapeutics against coronaviruses infection.

  6. Ankrd6 is a mammalian functional homolog of Drosophila planar cell polarity gene diego and regulates coordinated cellular orientation in the mouse inner ear.

    Science.gov (United States)

    Jones, Chonnettia; Qian, Dong; Kim, Sun Myoung; Li, Shuangding; Ren, Dongdong; Knapp, Lindsey; Sprinzak, David; Avraham, Karen B; Matsuzaki, Fumio; Chi, Fanglu; Chen, Ping

    2014-11-01

    The coordinated polarization of neighboring cells within the plane of the tissue, known as planar cell polarity (PCP), is a recurring theme in biology. It is required for numerous developmental processes for the form and function of many tissues and organs across species. The genetic pathway regulating PCP was first discovered in Drosophila, and an analogous but distinct pathway is emerging in vertebrates. It consists of membrane protein complexes known as core PCP proteins that are conserved across species. Here we report that the over-expression of the murine Ankrd6 (mAnkrd6) gene that shares homology with Drosophila core PCP gene diego causes a typical PCP phenotype in Drosophila, and mAnkrd6 can rescue the loss of function of diego in Drosophila. In mice, mAnkrd6 protein is asymmetrically localized in cells of the inner ear sensory organs, characteristic of components of conserved core PCP complexes. The loss of mAnkrd6 causes PCP defects in the inner ear sensory organs. Moreover, canonical Wnt signaling is significantly increased in mouse embryonic fibroblasts from mAnkrd6 knockout mice in comparison to wild type controls. Together, these results indicated that mAnkrd6 is a functional homolog of the Drosophila diego gene for mammalian PCP regulation and act to suppress canonical Wnt signaling.

  7. WNT16B is a new marker of cellular senescence that regulates p53 activity and the phosphoinositide 3-kinase/AKT pathway.

    Science.gov (United States)

    Binet, Romuald; Ythier, Damien; Robles, Ana I; Collado, Manuel; Larrieu, Delphine; Fonti, Claire; Brambilla, Elisabeth; Brambilla, Christian; Serrano, Manuel; Harris, Curtis C; Pedeux, Rémy

    2009-12-15

    Senescence is a tumor suppression mechanism that is induced by several stimuli, including oncogenic signaling and telomere shortening, and controlled by the p53/p21(WAF1) signaling pathway. Recently, a critical role for secreted factors has emerged, suggesting that extracellular signals are necessary for the onset and maintenance of senescence. Conversely, factors secreted by senescent cells may promote tumor growth. By using expression profiling techniques, we searched for secreted factors that were overexpressed in fibroblasts undergoing replicative senescence. We identified WNT16B, a member of the WNT family of secreted proteins. We found that WNT16B is overexpressed in cells undergoing stress-induced premature senescence and oncogene-induced senescence in both MRC5 cell line and the in vivo murine model of K-Ras(V12)-induced senescence. By small interfering RNA experiments, we observed that both p53 and WNT16B are necessary for the onset of replicative senescence. WNT16B expression is required for the full transcriptional activation of p21(WAF1). Moreover, WNT16B regulates activation of the phosphoinositide 3-kinase (PI3K)/AKT pathway. Overall, we identified WNT16B as a new marker of senescence that regulates p53 activity and the PI3K/AKT pathway and is necessary for the onset of replicative senescence.

  8. TOR Complexes and the Maintenance of Cellular Homeostasis.

    Science.gov (United States)

    Eltschinger, Sandra; Loewith, Robbie

    2016-02-01

    The Target of Rapamycin (TOR) is a conserved serine/threonine (ser/thr) kinase that functions in two, distinct, multiprotein complexes called TORC1 and TORC2. Each complex regulates different aspects of eukaryote growth: TORC1 regulates cell volume and/or mass by influencing protein synthesis and turnover, while TORC2, as detailed in this review, regulates cell surface area by influencing lipid production and intracellular turgor. TOR complexes function in feedback loops, implying that downstream effectors are also likely to be involved in upstream regulation. In this regard, the notion that TORCs function primarily as mediators of cellular and organismal homeostasis is fundamentally different from the current, predominate view of TOR as a direct transducer of extracellular biotic and abiotic signals.

  9. Focal adhesion kinase regulates pathogen-killing capability and life span of neutrophils via mediating both adhesion-dependent and -independent cellular signals.

    Science.gov (United States)

    Kasorn, Anongnard; Alcaide, Pilar; Jia, Yonghui; Subramanian, Kulandayan K; Sarraj, Bara; Li, Yitang; Loison, Fabien; Hattori, Hidenori; Silberstein, Leslie E; Luscinskas, William F; Luo, Hongbo R

    2009-07-15

    Various neutrophil functions such as phagocytosis, superoxide production, and survival are regulated by integrin signaling. Despite the essential role of focal adhesion kinase (FAK) in mediating this signaling pathway, its exact function in neutrophils is ill defined. In this study, we investigated the role of FAK in neutrophils using a myeloid-specific conditional FAK knockout mouse. As reported in many other cell types, FAK is required for regulation of focal adhesion dynamics when neutrophils adhere to fibronectin or ICAM-1. Adhesion on VCAM-1-coated surfaces and chemotaxis after adhesion were not altered in FAK null neutrophils. In addition, we observed significant reduction in NADPH oxidase-mediated superoxide production and complement-mediated phagocytosis in FAK null neutrophils. As a result, these neutrophils displayed decreased pathogen killing capability both in vitro and in vivo in a mouse peritonitis model. In adherent cells, the defects associated with FAK deficiency are likely due to suppression of phosphatidylinositol (3,4,5)-trisphosphate (PtdIns(3,4,5)P3) signaling and chemoattractant-elicited calcium signaling. Disruption of FAK also reduced chemoattractant-elicited superoxide production in suspended neutrophils in the absence of cell adhesion. This may be solely caused by suppression of PtdIns(3,4,5)P3 signaling in these cells, because the fMLP-elicited calcium signal was not altered. Consistent with decreased PtdIns(3,4,5)P3/Akt signaling in FAK null neutrophils, we also observed accelerated spontaneous death in these cells. Taken together, our results revealed previously unrecognized roles of FAK in neutrophil function and provided a potential therapeutic target for treatment of a variety of infectious and inflammatory diseases.

  10. Benefits from flywheel energy storage for area regulation in California - demonstration results : a study for the DOE Energy Storage Systems program.

    Energy Technology Data Exchange (ETDEWEB)

    Eyer, James M. (Distributed Utility Associates, Livermore, CA)

    2009-10-01

    This report documents a high-level analysis of the benefit and cost for flywheel energy storage used to provide area regulation for the electricity supply and transmission system in California. Area regulation is an 'ancillary service' needed for a reliable and stable regional electricity grid. The analysis was based on results from a demonstration, in California, of flywheel energy storage developed by Beacon Power Corporation (the system's manufacturer). Demonstrated was flywheel storage systems ability to provide 'rapid-response' regulation. Flywheel storage output can be varied much more rapidly than the output from conventional regulation sources, making flywheels more attractive than conventional regulation resources. The performance of the flywheel storage system demonstrated was generally consistent with requirements for a possible new class of regulation resources - 'rapid-response' energy-storage-based regulation - in California. In short, it was demonstrated that Beacon Power Corporation's flywheel system follows a rapidly changing control signal (the ACE, which changes every four seconds). Based on the results and on expected plant cost and performance, the Beacon Power flywheel storage system has a good chance of being a financially viable regulation resource. Results indicate a benefit/cost ratio of 1.5 to 1.8 using what may be somewhat conservative assumptions. A benefit/cost ratio of one indicates that, based on the financial assumptions used, the investment's financial returns just meet the investors target.

  11. Binding of sFRP-3 to EGF in the extra-cellular space affects proliferation, differentiation and morphogenetic events regulated by the two molecules.

    Directory of Open Access Journals (Sweden)

    Raffaella Scardigli

    Full Text Available BACKGROUND: sFRP-3 is a soluble antagonist of Wnts, widely expressed in developing embryos. The Wnt gene family comprises cysteine-rich secreted ligands that regulate cell proliferation, differentiation, organogenesis and oncogenesis of different organisms ranging from worms to mammals. In the canonical signal transduction pathway Wnt proteins bind to the extracellular domain of Frizzled receptors and consequently recruit Dishevelled (Dsh to the cell membrane. In addition to Wnt membrane receptors belonging to the Frizzled family, several other molecules have been described which share homology in the CRD domain and lack the putative trans-membrane domain, such as sFRP molecules (soluble Frizzled Related Protein. Among them, sFRP-3 was originally isolated from bovine articular cartilage and also as a component of the Spemann organizer. sFRP-3 blocks Wnt-8 induced axis duplication in Xenopus embryos and binds to the surface of cells expressing a membrane-anchored form of Wnt-1. Injection of sFRP-3 mRNA blocks expression of XMyoD mRNA and leads to embryos with enlarged heads and shortened trunks. METHODOLOGY/PRINCIPAL FINDINGS: Here we report that sFRP-3 specifically blocks EGF-induced fibroblast proliferation and foci formation. Over-expression of sFRP-3 reverts EGF-mediated inhibition of hair follicle development in the mouse ectoderm while its ablation in Xenopus maintains EGF-mediated inhibition of ectoderm differentiation. Conversely, over-expression of EGF reverts the inhibition of somitic myogenesis and axis truncation in Xenopus and mouse embryos caused by sFRP-3. In vitro experiments demonstrated a direct binding of EGF to sFRP-3 both on heparin and on the surface of CHO cells where the molecule had been membrane anchored. CONCLUSIONS/SIGNIFICANCE: sFRP-3 and EGF reciprocally inhibit their effects on cell proliferation, differentiation and morphogenesis and indeed are expressed in contiguous domains of the embryo, suggesting that in

  12. The Fruits of Wampee Inhibit H2O2-Induced Apoptosis in PC12 Cells via the NF-κB Pathway and Regulation of Cellular Redox Status

    Directory of Open Access Journals (Sweden)

    Xiaobin Zeng

    2014-06-01

    Full Text Available Wampee (Clausena lansium fruits (CLS, whose pulp can be used to prepare fruit cups, desserts, jam, or jelly, can be eaten along with the peel. In this study, a PC12 cell model was built to observe the protective effect of CLS against H2O2-induced oxidative stress. We found that pretreatment with CLS increased cell viability and inhibited cytotoxicity, caspase-3 activity and DNA condensation. CLS also attenuated the increase in ROS production and MMP reduction. Moreover, we attempted to determine whether CLS suppressed the expression and phosphorylation of NF-κB. Western blot and immunostaining assay revealed that CLS inhibited H2O2-induced up-regulation of NF-κB p65 and pNF-κB p65. And CLS significantly suppressed the translocation of NF-κB p65 and pNF-κB p65 from cytoplasm to nuclear. Also, seven major compounds including a new flavanoid, luteolin-4'-O-β-d-gluco-pyranoside (3 and six known compounds 1,2, 4–7 were isolated and identified from CLS. Their antioxidative and H2O2-induced PC12 cell apoptosis-reversing activity were determined. These findings suggest that CLS and its major constituents (flavanoids may be potential antioxidant agents and should encourage further research into their use as a functional food for neurodegenerative diseases.

  13. Ankrd2/ARPP is a novel Akt2 specific substrate and regulates myogenic differentiation upon cellular exposure to H2O2

    Science.gov (United States)

    Cenni, Vittoria; Bavelloni, Alberto; Beretti, Francesca; Tagliavini, Francesca; Manzoli, Lucia; Lattanzi, Giovanna; Maraldi, Nadir M.; Cocco, Lucio; Marmiroli, Sandra

    2011-01-01

    Activation of Akt-mediated signaling pathways is crucial for survival, differentiation, and regeneration of muscle cells. A proteomic-based search for novel substrates of Akt was therefore undertaken in C2C12 murine muscle cells exploiting protein characterization databases in combination with an anti–phospho-Akt substrate antibody. A Scansite database search predicted Ankrd2 (Ankyrin repeat domain protein 2, also known as ARPP) as a novel substrate of Akt. In vitro and in vivo studies confirmed that Akt phosphorylates Ankrd2 at Ser-99. Moreover, by kinase assay with recombinant Akt1 and Akt2, as well as by single-isoform silencing, we demonstrated that Ankrd2 is a specific substrate of Akt2. Ankrd2 is typically found in skeletal muscle cells, where it mediates the transcriptional response to stress conditions. In an attempt to investigate the physiological implications of Ankrd2 phosphorylation by Akt2, we found that oxidative stress induced by H2O2 triggers this phosphorylation. Moreover, the forced expression of a phosphorylation-defective mutant form of Ankrd2 in C2C12 myoblasts promoted a faster differentiation program, implicating Akt-dependent phosphorylation at Ser-99 in the negative regulation of myogenesis in response to stress conditions. PMID:21737686

  14. Deliberative democracy and co-management of natural resources: The case of Funäsdalen snowmobile regulation area

    Directory of Open Access Journals (Sweden)

    Anna Karin Elise Zachrisson

    2009-09-01

    Full Text Available The purpose of this article is to deepen the understanding of how co-management and deliberative democracy relate to one another. Deliberation is an understudied aspect of common-pool resource theory that could be developed by a closer connection to deliberative democratic theory. Co-management studies may also provide needed empirical insights to deliberative democratic theory. A framework is developed to analyze to what degree co-management arrangements incorporate deliberative elements. To test its usefulness, a case study of a co-management process in Sweden is analyzed. In Funäsdalsfjällen, a conflict-ridden situation caused by snowmobiles ended in agreement and the establishment of a municipal regulation area. Central and regional authorities initially failed to resolve the conflict, but when the municipality started working directly with the relevant interest groups, agreement was reached. Deliberative elements are shown central to the success, and it is concluded that co-management and deliberative democratic approaches indeed do cross-fertilize one another.

  15. Prognosis of Different Cellular Generations

    Directory of Open Access Journals (Sweden)

    Preetish Ranjan

    2013-04-01

    Full Text Available Technological advancement in mobile telephony from 1G to 3G, 4G and 5G has a very axiomatic fact that made an entire world a global village. The cellular system employs a different design approach and technology that most commercial radio and television system use. In the cellular system, the service area is divided into cells and a transmitter is designed to serve an individual cell. The system seeks to make efficient use of available channels by using low-power transmitters to allow frequency reuse at a smaller distance. Maximizing the number of times each channel can be reused in a given geographical area is the key to an efficient cellular system design. During the past three decades, the world has seen significant changes in telecommunications industry. There have been some remarkable aspects to the rapid growth in wireless communications, as seen by the large expansion in mobile systems. This paper focuses on “Past, Present & Future of Cellular Telephony” and some light has been thrown upon the technologies of the cellular systems, namely 1G, 2G, 2.5G, 3G and future generations like 4G and 5G systems as well.

  16. ZIP8 is an iron and zinc transporter whose cell-surface expression is up-regulated by cellular iron loading.

    Science.gov (United States)

    Wang, Chia-Yu; Jenkitkasemwong, Supak; Duarte, Stephanie; Sparkman, Brian K; Shawki, Ali; Mackenzie, Bryan; Knutson, Mitchell D

    2012-10-05

    ZIP8 (SLC39A8) belongs to the ZIP family of metal-ion transporters. Among the ZIP proteins, ZIP8 is most closely related to ZIP14, which can transport iron, zinc, manganese, and cadmium. Here we investigated the iron transport ability of ZIP8, its subcellular localization, pH dependence, and regulation by iron. Transfection of HEK 293T cells with ZIP8 cDNA enhanced the uptake of (59)Fe and (65)Zn by 200 and 40%, respectively, compared with controls. Excess iron inhibited the uptake of zinc and vice versa. In RNA-injected Xenopus oocytes, ZIP8-mediated (55)Fe(2+) transport was saturable (K(0.5) of ∼0.7 μm) and inhibited by zinc. ZIP8 also mediated the uptake of (109)Cd(2+), (57)Co(2+), (65)Zn(2+) > (54)Mn(2+), but not (64)Cu (I or II). By using immunofluorescence analysis, we found that ZIP8 expressed in HEK 293T cells localized to the plasma membrane and partially in early endosomes. Iron loading increased total and cell-surface levels of ZIP8 in H4IIE rat hepatoma cells. We also determined by using site-directed mutagenesis that asparagine residues 40, 88, and 96 of rat ZIP8 are glycosylated and that N-glycosylation is not required for iron or zinc transport. Analysis of 20 different human tissues revealed abundant ZIP8 expression in lung and placenta and showed that its expression profile differs markedly from ZIP14, suggesting nonredundant functions. Suppression of endogenous ZIP8 expression in BeWo cells, a placental cell line, reduced iron uptake by ∼40%, suggesting that ZIP8 participates in placental iron transport. Collectively, these data identify ZIP8 as an iron transport protein that may function in iron metabolism.

  17. Clathrin assembly protein CALM plays a critical role in KIT signaling by regulating its cellular transport from early to late endosomes in hematopoietic cells.

    Directory of Open Access Journals (Sweden)

    Shinya Rai

    Full Text Available CALM is implicated in the formation of clathrin-coated vesicles, which mediate endocytosis and intracellular trafficking of growth factor receptors and nutrients. We previously found that CALM-deficient mice suffer from severe anemia due to the impaired clathrin-mediated endocytosis of transferrin receptor in immature erythroblast. However, CALM has been supposed to regulate the growth and survival of hematopoietic stem/progenitor cells. So, in this study, we focused on the function of CALM in these cells. We here show that the number of Linage-Sca-1+KIT+ (LSK cells decreased in the fetal liver of CALM-/- mice. Also, colony forming activity was impaired in CALM-/- LSK cells. In addition, SCF, FLT3, and TPO-dependent growth was severely impaired in CALM-/- LSK cells, while they can normally proliferate in response to IL-3 and IL-6. We also examined the intracellular trafficking of KIT using CALM-/- murine embryonic fibroblasts (MEFs engineered to express KIT. At first, we confirmed that endocytosis of SCF-bound KIT was not impaired in CALM-/- MEFs by the internalization assay. However, SCF-induced KIT trafficking from early to late endosome was severely impaired in CALM-/- MEFs. As a result, although intracellular KIT disappeared 30 min after SCF stimulation in wild-type (WT MEFs, it was retained in CALM-/- MEFs. Furthermore, SCF-induced phosphorylation of cytosolic KIT was enhanced and prolonged in CALM-/- MEFs compared with that in WT MEFs, leading to the excessive activation of Akt. Similar hyperactivation of Akt was observed in CALM-/- KIT+ cells. These results indicate that CALM is essential for the intracellular trafficking of KIT and its normal functions. Also, our data demonstrate that KIT located in the early endosome can activate downstream molecules as a signaling endosome. Because KIT activation is involved in the pathogenesis of some malignancies, the manipulation of CALM function would be an attractive therapeutic strategy.

  18. 75 FR 12961 - Regulation of the Interstate Movement of Lemons from Areas Quarantined for Mediterranean Fruit Fly

    Science.gov (United States)

    2010-03-18

    ... Mediterranean Fruit Fly AGENCY: Animal and Plant Health Inspection Service, USDA. ACTION: Final rule. SUMMARY: We are amending the list of regulated articles in our domestic fruit fly quarantine regulations. The... commercial packinghouses are not regulated articles for Mediterranean fruit fly. We are amending...

  19. Analysis of expression, cellular localization, and function of three inhibitors of apoptosis (IAPs from Litopenaeus vannamei during WSSV infection and in regulation of antimicrobial peptide genes (AMPs.

    Directory of Open Access Journals (Sweden)

    Pei-Hui Wang

    . Taken together, these results reveal that LvIAP1 and LvIAP3 might participate in the host defense against WSSV infection, and LvIAP2 might be involved in the regulation of shrimp AMPs.

  20. Hierarchical Cellular Structures in High-Capacity Cellular Communication Systems

    CERN Document Server

    Jain, R K; Agrawal, N K

    2011-01-01

    In the prevailing cellular environment, it is important to provide the resources for the fluctuating traffic demand exactly in the place and at the time where and when they are needed. In this paper, we explored the ability of hierarchical cellular structures with inter layer reuse to increase the capacity of mobile communication network by applying total frequency hopping (T-FH) and adaptive frequency allocation (AFA) as a strategy to reuse the macro and micro cell resources without frequency planning in indoor pico cells [11]. The practical aspects for designing macro- micro cellular overlays in the existing big urban areas are also explained [4]. Femto cells are inducted in macro / micro / pico cells hierarchical structure to achieve the required QoS cost effectively.

  1. The AreA transcription factor mediates the regulation of deoxynivalenol (DON) synthesis by ammonium and cyclic adenosine monophosphate (cAMP) signalling in Fusarium graminearum.

    Science.gov (United States)

    Hou, Rui; Jiang, Cong; Zheng, Qian; Wang, Chenfang; Xu, Jin-Rong

    2015-12-01

    Deoxynivalenol (DON), a trichothecene mycotoxin produced by Fusarium graminearum, is harmful to humans and animals. Because different nitrogen sources are known to have opposite effects on DON production, in this study, we characterized the regulatory mechanisms of the AREA transcription factor in trichothecene biosynthesis. The ΔareA mutant showed significantly reduced vegetative growth and DON production in cultures inoculated with hyphae. Suppression of TRI gene expression and DON production by ammonium were diminished in the ΔareA mutant. The deletion of AREA also affected the stimulatory effects of arginine on DON biosynthesis. The AreA-green fluorescent protein (GFP) fusion complemented the ΔareA mutant, and its localization to the nucleus was enhanced under nitrogen starvation conditions. Site-directed mutagenesis showed that the conserved predicted protein kinase A (PKA) phosphorylation site S874 was important for AreA function, indicating that AreA may be a downstream target of the cyclic adenosine monophosphate (cAMP)-PKA pathway, which is known to regulate DON production. We also showed that AreA interacted with Tri10 in co-immunoprecipitation assays. The interaction of AreA with Tri10 is probably related to its role in the regulation of TRI gene expression. Interestingly, the ΔareA mutant showed significantly reduced PKA activity and expression of all three predicted ammonium permease (MEP) genes, in particular MEP1, under low ammonium conditions. Taken together, our results show that AREA is involved in the regulation of DON production by ammonium suppression and the cAMP-PKA pathway. The AreA transcription factor may interact with Tri10 and control the expression and up-regulation of MEP genes.

  2. ING proteins in cellular senescence.

    Science.gov (United States)

    Menéndez, Camino; Abad, María; Gómez-Cabello, Daniel; Moreno, Alberto; Palmero, Ignacio

    2009-05-01

    Cellular senescence is an effective anti-tumor barrier that acts by restraining the uncontrolled proliferation of cells carrying potentially oncogenic alterations. ING proteins are putative tumor suppressor proteins functionally linked to the p53 pathway and to chromatin regulation. ING proteins exert their tumor-protective action through different types of responses. Here, we review the evidence on the participation of ING proteins, mainly ING1 and ING2, in the implementation of the senescent response. The currently available data support an important role of ING proteins as regulators of senescence, in connection with the p53 pathway and chromatin organization.

  3. Reinforcement-related regulation of AMPA glutamate receptor subunits in the ventral tegmental area enhances motivation for cocaine.

    Science.gov (United States)

    Choi, Kwang Ho; Edwards, Scott; Graham, Danielle L; Larson, Erin B; Whisler, Kimberly N; Simmons, Diana; Friedman, Allyson K; Walsh, Jessica J; Rahman, Zia; Monteggia, Lisa M; Eisch, Amelia J; Neve, Rachael L; Nestler, Eric J; Han, Ming-Hu; Self, David W

    2011-05-25

    Chronic cocaine use produces numerous biological changes in brain, but relatively few are functionally associated with cocaine reinforcement. Here we show that daily intravenous cocaine self-administration, but not passive cocaine administration, induces dynamic upregulation of the AMPA glutamate receptor subunits GluR1 and GluR2 in the ventral tegmental area (VTA) of rats. Increases in GluR1 protein and GluR1(S845) phosphorylation are associated with increased GluR1 mRNA in self-administering animals, whereas increased GluR2 protein levels occurred despite substantial decreases in GluR2 mRNA. We investigated the functional significance of GluR1 upregulation in the VTA on cocaine self-administration using localized viral-mediated gene transfer. Overexpression of GluR1(WT) in rat VTA primarily infected dopamine neurons (75%) and increased AMPA receptor-mediated membrane rectification in these neurons with AMPA application. Similar GluR1(WT) overexpression potentiated locomotor responses to intra-VTA AMPA, but not NMDA, infusions. In cocaine self-administering animals, overexpression of GluR1(WT) in the VTA markedly increased the motivation for cocaine injections on a progressive ratio schedule of cocaine reinforcement. In contrast, overexpression of protein kinase A-resistant GluR1(S845A) in the VTA reduced peak rates of cocaine self-administration on a fixed ratio reinforcement schedule. Neither viral vector altered sucrose self-administration, and overexpression of GluR1(WT) or GluR1(S845A) in the adjacent substantia nigra had no effect on cocaine self-administration. Together, these results suggest that dynamic regulation of AMPA receptors in the VTA during cocaine self-administration contributes to cocaine addiction by acting to facilitate subsequent cocaine use.

  4. Attitudes regarding new enterprise risk and control regulations by the active population of the Geneva area: Cahier de recherche

    OpenAIRE

    Catenazzo, Giuseppe; Fragnière, Emmanuel

    2008-01-01

    Nowadays, professional bodies as well as public authorities are setting up new regulations and standards in order to deploy risk management approaches in the non-financial industries. For instance, Switzerland has recently introduced a new regulation on Internal control that forces most SMEs to implement an ICS (Internal Control System). However, introducing or dealing with new risk control regulations might not bring the desired effect to the organisation: logistical and psychological barrie...

  5. Flat Cellular (UMTS) Networks

    NARCIS (Netherlands)

    Bosch, H.G.P.; Samuel, L.G.; Mullender, S.J.; Polakos, P.; Rittenhouse, G.

    2007-01-01

    Traditionally, cellular systems have been built in a hierarchical manner: many specialized cellular access network elements that collectively form a hierarchical cellular system. When 2G and later 3G systems were designed there was a good reason to make system hierarchical: from a cost-perspective i

  6. 基于手机信令数据的上海市域职住空间分析%Job-Housing Spatial Distribution Analysis in Shanghai Metropolitan Area Based on Cellular Sig-naling Data

    Institute of Scientific and Technical Information of China (English)

    张天然

    2016-01-01

    The spatial relationship between residence and workplace primarily determines the urban spatial layout. This paper proposes a methodology to calculate commuting distance between residence and work-place by region with cellular signaling data. The comparison result shows that job-housing spatial distribu-tion and commuting distance obtained from both travel surveys and cellular phone data are very similar. Through analyzing the job-housing spatial distribution and commuting distance in the central district and surrounding areas in Shanghai, the paper proposes a concept of balance in job-housing corridors. By re-viewing the relationship between regions with imbalanced job-housing corridors and the degree of rail tran-sit congestion, the paper emphasizes the importance of land use development for the balanced job-housing corridors. The paper discusses the zoning size impact of a new town on the statistical analysis through ana-lyzing job-housing spatial characteristics at different new towns. The result shows that the job-housing dis-tribution of new towns are relatively independent, and the employment rate of residents within new towns is relatively high.%居民居住地与工作地的空间关系是城市空间布局的重要依据.基于手机信令数据,提出分区域的居民通勤距离和就业岗位通勤距离计算方法.通过对比验证了手机信令数据与居民出行调查数据的职住空间和距离分布特征较为吻合.重点分析上海市中心城区及周边地区的职住空间关系及通勤距离.提出职住通道平衡概念,并分析职住通道不平衡地区与轨道交通拥挤程度的关系,指出土地利用布局优化对职住通道平衡的重要性.通过分析不同新城的职住空间特征,探讨新城范围划定对统计分析的影响,总结了新城职住空间较为独立、居民内部就业率较高的特征.

  7. SOCIAL DEVELOPMENT OF RURAL AREAS AS A MAIN DIRECTION OF GOVERNMENT REGULATION OF AGRO-INDUSTRIAL COMPLEX IN THE KRASNODAR REGION

    Directory of Open Access Journals (Sweden)

    Burkovskiy P. V.

    2015-10-01

    Full Text Available This article is devoted to evaluation and analysis of basic trends, that revealing modern situation and current level of the development of social sphere in rural areas in the Krasnodar region. We have carried out a theoretical view to current problems in gasification, water supply, and development infrastructure objects in rural areas of the region. The authors have considered main attention is a social standards when developing targeted programs for the social development of rural areas. The article provides a specific list of normative values still indicators as the presence of a central gas supply, the central and the local water supply (hot and cold, the length of the street and objects known telephone. We have explained the mechanism of government regulations aimed at social infrastructure in rural areas of the Krasnodar region and the organization work of municipal institutions to protect and maintenance local roads. Based on the above authors’ suggestions, it is planned to achieve more definable and justifiable opinion in the implementation of municipal regulation social development rural areas designed on the basis targeted programs in the subject area. Actual and significant to readers are measures of gap consumer budget and the level of monetary income between urban and rural areas presented in the article

  8. 7 CFR 301.32-4 - Conditions governing the interstate movement of regulated articles from quarantined areas.

    Science.gov (United States)

    2010-01-01

    ... area quarantined for Mexican or sapote fruit fly and that are moving interstate from such an area are... in an orchard within the quarantined area, the identity of the avocados must be maintained from field... marked with the identity of the grower and the packinghouse. (iv) Any boxes of Hass avocados packed...

  9. The AreA transcription factor in Fusarium graminearum regulates the use of some nonpreferred nitrogen sources and secondary metabolite production

    DEFF Research Database (Denmark)

    Giese, Nanna Henriette; Sondergaard, Teis Esben; Sorensen, Jens Laurids

    2013-01-01

    Growth conditions are known to affect the production of secondary metabolites in filamentous fungi. The influence of different nitrogen sources and the transcription factor AreA on the production of mycotoxins in Fusarium graminearum was examined. Growth on glutamine or NH4-sources was poor...... and asparagine was found to be a preferential nitrogen source for F. graminearum. Deletion of areA led to poor growth on NaNO3 suggesting its involvement in regulation of the nitrate reduction process. In addition utilization of aspartic acid, histidine, isoleucine, leucine, threonine, tyrosine, and valine...... as nitrogen sources was shown to depend of a functional AreA. AreA was shown to be required for the production of the mycotoxins deoxynivalenol (DON), zearalenone, and fusarielin H regardless of the nutrient medium. Deletion of nmr, the repressor of AreA under nitrogen sufficient conditions, had little effect...

  10. CLNR1, the AREA/NIT2-like global nitrogen regulator of the plant fungal pathogen Colletotrichum lindemuthianum is required for the infection cycle.

    Science.gov (United States)

    Pellier, Anne-Laure; Laugé, Richard; Veneault-Fourrey, Claire; Langin, Thierry

    2003-05-01

    Nitrogen starvation is generally assumed to be encountered by biotrophic and hemibiotrophic plant fungal pathogens at the beginning of their infection cycle. We tested whether nitrogen starvation constitutes a cue regulating genes that are required for pathogenicity of Colletotrichum lindemuthianum, a fungal pathogen of common bean. The clnr1 (C. lindemuthianumnitrogen regulator 1) gene, the areA/nit-2 orthologue of C. lindemuthianum, was isolated. The predicted CLNR1 protein exhibits high amino acid sequence similarities with the AREA and NIT2 global fungal nitrogen regulators. Targeted clnr1- mutants are unable to use a wide array of nitrogen sources, indicating that clnr1 is the C. lindemuthianum major nitrogen regulatory gene. The clnr1- mutants are non-pathogenic, although few anthracnose lesions seldom occur on whole plantlets. Surprisingly, cytological analysis reveals that the clnr1- mutants are not disturbed from the penetration stage until the end of the biotrophic phase, but that they are impaired during the setting up of the necrotrophic phase. Thus, through CLNR1, nitrogen starvation constitutes a cue for the regulation of genes that are compulsory for this stage of the C. lindemuthianum infection process. Additionally, clnr1- mutants complemented with the Aspergillus nidulans areA gene are fully pathogenic, indicating that areA is able to activate the C. lindemuthianum suited genes, normally under the control of clnr1.

  11. The insect cellular immune response

    Institute of Scientific and Technical Information of China (English)

    Michael R. Strand

    2008-01-01

    The innate immune system of insects is divided into humoral defenses that include the production of soluble effector molecules and cellular defenses like phagocytosis and encapsulation that are mediated by hemocytes. This review summarizes current understanding of the cellular immune response. Insects produce several terminally differentiated types of hemocytes that are distinguished by morphology, molecular and antigenic markers, and function. The differentiated hemocytes that circulate in larval or nymphal stage insects arise from two sources: progenitor cells produced during embryogenesis and mesodermally derived hematopoietic organs. Regulation of hematopoiesis and hemocyte differentiation also involves several different signaling pathways. Phagocytosis and encapsulation require that hemocytes first recognize a given target as foreign followed by activation of downstream signaling and effector responses. A number of humoral and cellular receptors have been identified that recognize different microbes and multicellular parasites. In turn, activation of these receptors stimulates a number of signaling pathways that regulate different hemocyte functions. Recent studies also identify hemocytes as important sources of a number of humoral effector molecules required for killing different foreign invaders.

  12. Hippocampal Deletion of BDNF Gene Attenuates Gamma Oscillations in Area CA1 by Up-Regulating 5-HT3 Receptor

    OpenAIRE

    Ying Huang; Alexei Morozov

    2011-01-01

    BACKGROUND: Pyramidal neurons in the hippocampal area CA3 express high levels of BDNF, but how this BDNF contributes to oscillatory properties of hippocampus is unknown. METHODOLOGY/PRINCIPAL FINDINGS: Here we examined carbachol-induced gamma oscillations in hippocampal slices lacking BDNF gene in the area CA3. The power of oscillations was reduced in the hippocampal area CA1, which coincided with increases in the expression and activity of 5-HT3 receptor. Pharmacological block of this recept...

  13. The mammary cellular hierarchy and breast cancer.

    Science.gov (United States)

    Oakes, Samantha R; Gallego-Ortega, David; Ormandy, Christopher J

    2014-11-01

    Advances in the study of hematopoietic cell maturation have paved the way to a deeper understanding the stem and progenitor cellular hierarchy in the mammary gland. The mammary epithelium, unlike the hematopoietic cellular hierarchy, sits in a complex niche where communication between epithelial cells and signals from the systemic hormonal milieu, as well as from extra-cellular matrix, influence cell fate decisions and contribute to tissue homeostasis. We review the discovery, definition and regulation of the mammary cellular hierarchy and we describe the development of the concepts that have guided our investigations. We outline recent advances in in vivo lineage tracing that is now challenging many of our assumptions regarding the behavior of mammary stem cells, and we show how understanding these cellular lineages has altered our view of breast cancer.

  14. Sponging of Cellular Proteins by Viral RNAs

    OpenAIRE

    Charley, Phillida A.; Wilusz, Jeffrey

    2014-01-01

    Viral RNAs accumulate to high levels during infection and interact with a variety of cellular factors including miRNAs and RNA-binding proteins. Although many of these interactions exist to directly modulate replication, translation and decay of viral transcripts, evidence is emerging that abundant viral RNAs may in certain cases serve as a sponge to sequester host non coding RNAs and proteins. By effectively reducing the ability of cellular RNA binding proteins to regulate host cell gene exp...

  15. On the Behavior Characteristics of Cellular Automata

    Institute of Scientific and Technical Information of China (English)

    CHEN Jin-cai; ZHANG Jiang-ling; FENG Dan

    2005-01-01

    In this paper, the inherent relationships between the running regulations and behavior characteristics of cellular automata are presented; an imprecise taxonomy of such systems is put forward; the three extreme cases of stable systems are discussed; and the illogicalness of evolutional strategies of cellular automata is analyzed. The result is suitable for the emulation and prediction of behavior of discrete dynamics systems; especially it can be taken as an important analysis means of dynamic performance of complex networks.

  16. Peroxisome Metabolism and Cellular Aging

    Science.gov (United States)

    Titorenko, Vladimir I.; Terlecky, Stanley R.

    2010-01-01

    The essential role of peroxisomes in fatty acid oxidation, anaplerotic metabolism, and hydrogen peroxide turnover is well established. Recent findings suggest these and other related biochemical processes governed by the organelle may also play a critical role in regulating cellular aging. The goal of this review is to summarize and integrate into a model, the evidence that peroxisome metabolism actually helps define the replicative and chronological age of a eukaryotic cell. In this model, peroxisomal reactive oxygen species (ROS) are seen as altering organelle biogenesis and function, and eliciting changes in the dynamic communication networks that exist between peroxisomes and other cellular compartments. At low levels, peroxisomal ROS activate an anti-aging program in the cell; at concentrations beyond a specific threshold, a pro-aging course is triggered. PMID:21083858

  17. Optimal Band Allocation for Cognitive Cellular Networks

    CERN Document Server

    Liu, Tingting

    2011-01-01

    FCC new regulation for cognitive use of the TV white space spectrum provides a new means for improving traditional cellular network performance. But it also introduces a number of technical challenges. This letter studies one of the challenges, that is, given the significant differences in the propagation property and the transmit power limitations between the cellular band and the TV white space, how to jointly utilize both bands such that the benefit from the TV white space for improving cellular network performance is maximized. Both analytical and simulation results are provided.

  18. 78 FR 70307 - Guidance for Industry: Preclinical Assessment of Investigational Cellular and Gene Therapy...

    Science.gov (United States)

    2013-11-25

    ... Investigational Cellular and Gene Therapy Products; Availability AGENCY: Food and Drug Administration, HHS. ACTION... entitled ``Guidance for Industry: Preclinical Assessment of Investigational Cellular and Gene Therapy... and Gene Therapies (OCTGT). The product areas covered by this guidance are cellular therapy,...

  19. Cellular neurothekeoma with melanocytosis.

    Science.gov (United States)

    Wu, Ren-Chin; Hsieh, Yi-Yueh; Chang, Yi-Chin; Kuo, Tseng-Tong

    2008-02-01

    Cellular neurothekeoma (CNT) is a benign dermal tumor mainly affecting the head and neck and the upper extremities. It is characterized histologically by interconnecting fascicles of plump spindle or epithelioid cells with ample cytoplasm infiltrating in the reticular dermis. The histogenesis of CNT has been controversial, although it is generally regarded as an immature counterpart of classic/myxoid neurothekeoma, a tumor with nerve sheath differentiation. Two rare cases of CNT containing melanin-laden cells were described. Immunohistochemical study with NKI/C3, vimentin, epithelial membrane antigen, smooth muscle antigen, CD34, factor XIIIa, collagen type IV, S100 protein and HMB-45 was performed. Both cases showed typical growth pattern of CNT with interconnecting fascicles of epithelioid cells infiltrating in collagenous stroma. One of the nodules contained areas exhibiting atypical cytological features. Melanin-laden epithelioid or dendritic cells were diffusely scattered throughout one nodule, and focally present in the peripheral portion of the other nodule. Both nodules were strongly immunoreactive to NKI/C3 and vimentin, but negative to all the other markers employed. CNT harboring melanin-laden cells may pose diagnostic problems because of their close resemblance to nevomelanocytic lesions and other dermal mesenchymal tumors. These peculiar cases may also provide further clues to the histogenesis of CNT.

  20. Cellular functions of the microprocessor.

    Science.gov (United States)

    Macias, Sara; Cordiner, Ross A; Cáceres, Javier F

    2013-08-01

    The microprocessor is a complex comprising the RNase III enzyme Drosha and the double-stranded RNA-binding protein DGCR8 (DiGeorge syndrome critical region 8 gene) that catalyses the nuclear step of miRNA (microRNA) biogenesis. DGCR8 recognizes the RNA substrate, whereas Drosha functions as an endonuclease. Recent global analyses of microprocessor and Dicer proteins have suggested novel functions for these components independent of their role in miRNA biogenesis. A HITS-CLIP (high-throughput sequencing of RNA isolated by cross-linking immunoprecipitation) experiment designed to identify novel substrates of the microprocessor revealed that this complex binds and regulates a large variety of cellular RNAs. The microprocessor-mediated cleavage of several classes of RNAs not only regulates transcript levels, but also modulates alternative splicing events, independently of miRNA function. Importantly, DGCR8 can also associate with other nucleases, suggesting the existence of alternative DGCR8 complexes that may regulate the fate of a subset of cellular RNAs. The aim of the present review is to provide an overview of the diverse functional roles of the microprocessor.

  1. 50 CFR 648.80 - NE Multispecies regulated mesh areas and restrictions on gear and methods of fishing.

    Science.gov (United States)

    2010-10-01

    ... bycatch standard could be modified for a stock that is not in an overfished condition, or if overfishing... the change will not delay a rebuilding program, or result in overfishing or an overfished condition... prohibition on the possession of regulated multispecies that are overfished or where overfishing is...

  2. TV White spaces for wireless broadband in rural areas: the regulator, broadcaster and telecommunication(s) operator viewpoint

    CSIR Research Space (South Africa)

    Mfupe, LP

    2012-05-01

    Full Text Available from potential harmful interference of the secondary users through the use of regulator controlled spatial-temporal databases. Simultaneously, the delivery of low-cost service(s) to the end-user(s) could be achieved by the telecommunication operator...

  3. 76 FR 71928 - Defense Federal Acquisition Regulation Supplement; Updates to Wide Area WorkFlow (DFARS Case 2011...

    Science.gov (United States)

    2011-11-21

    ... Contractor shall-- (1) Have a designated electronic business point of contact in the Central Contractor... and receiving reports in electronic format. DATES: Comments on the proposed rule should be submitted... procedures in the Defense Federal Acquisition Regulation Supplement (DFARS) for electronic submission...

  4. 77 FR 3123 - Special Regulations, Areas of the National Park System, Cape Hatteras National Seashore-Off-Road...

    Science.gov (United States)

    2012-01-23

    ... sound and ocean beaches. Improved access, increased population, and the popularity of the sport utility... completed or published as a special regulation as required by 36 CFR 4.10(b). Motivated in part by a decline... popularity of one alternative over another. These changes were subsequently reflected in the FEIS and...

  5. 33 CFR 165.1122 - San Diego Bay, Mission Bay and their Approaches-Regulated navigation area.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false San Diego Bay, Mission Bay and... Coast Guard District § 165.1122 San Diego Bay, Mission Bay and their Approaches—Regulated navigation... waters of San Diego Bay, Mission Bay, and their approaches encompassed by a line commencing at Point La...

  6. 77 FR 38731 - Defense Federal Acquisition Regulation Supplement: Updates to Wide Area WorkFlow (DFARS Case 2011...

    Science.gov (United States)

    2012-06-29

    ..., distributive impacts, and equity). E.O. 13563 emphasizes the importance of quantifying both costs and benefits.... Exceptions to the use of Wide Area WorkFlow are at 232.7002(a). * * * * * PART 232--CONTRACT FINANCING 0 3...

  7. Repaglinide at a cellular level

    DEFF Research Database (Denmark)

    Krogsgaard Thomsen, M; Bokvist, K; Høy, M

    2002-01-01

    To investigate the hormonal and cellular selectivity of the prandial glucose regulators, we have undertaken a series of experiments, in which we characterised the effects of repaglinide and nateglinide on ATP-sensitive potassium ion (KATP) channel activity, membrane potential and exocytosis in rat...... pancreatic alpha-cells and somatotrophs. We found a pharmacological dissociation between the actions on KATP channels and exocytosis and suggest that compounds that, unlike repaglinide, have direct stimulatory effects on exocytosis in somatotrophs and alpha- and beta-cells, such as sulphonylureas...... and nateglinide, may have a clinically undesirable general stimulatory effect on cells within the endocrine system....

  8. The Regulation of Iron Absorption and Homeostasis

    Science.gov (United States)

    Wallace, Daniel F

    2016-01-01

    Iron is an essential element in biology, required for numerous cellular processes. Either too much or too little iron can be detrimental, and organisms have developed mechanisms for balancing iron within safe limits. In mammals there are no controlled mechanisms for the excretion of excess iron, hence body iron homeostasis is regulated at the sites of absorption, utilisation and recycling. This review will discuss the discoveries that have been made in the past 20 years into advancing our understanding of iron homeostasis and its regulation. The study of iron-associated disorders, such as the iron overload condition hereditary haemochromatosis and various forms of anaemia have been instrumental in increasing our knowledge in this area, as have cellular and animal model studies. The liver has emerged as the major site of systemic iron regulation, being the location where the iron regulatory hormone hepcidin is produced. Hepcidin is a negative regulator of iron absorption and recycling, achieving this by binding to the only known cellular iron exporter ferroportin and causing its internalisation and degradation, thereby reducing iron efflux from target cells and reducing serum iron levels. Much of the research in the iron metabolism field has focussed on the regulation of hepcidin and its interaction with ferroportin. The advances in this area have greatly increased our knowledge of iron metabolism and its regulation and have led to the development of novel diagnostics and therapeutics for iron-associated disorders.

  9. Reversible quantum cellular automata

    CERN Document Server

    Schumacher, B

    2004-01-01

    We define quantum cellular automata as infinite quantum lattice systems with discrete time dynamics, such that the time step commutes with lattice translations and has strictly finite propagation speed. In contrast to earlier definitions this allows us to give an explicit characterization of all local rules generating such automata. The same local rules also generate the global time step for automata with periodic boundary conditions. Our main structure theorem asserts that any quantum cellular automaton is structurally reversible, i.e., that it can be obtained by applying two blockwise unitary operations in a generalized Margolus partitioning scheme. This implies that, in contrast to the classical case, the inverse of a nearest neighbor quantum cellular automaton is again a nearest neighbor automaton. We present several construction methods for quantum cellular automata, based on unitaries commuting with their translates, on the quantization of (arbitrary) reversible classical cellular automata, on quantum c...

  10. Interworking of wireless lans and cellular networks

    CERN Document Server

    Song, Wei

    2014-01-01

    The next-generation of wireless communications are envisioned to be supported by heterogeneous networks by using various wireless access technologies. The popular cellular networks and wireless local area networks (WLANs) present perfectly complementary characteristics in terms of service capacity, mobility support, and quality-of-service (QoS) provisioning. The cellular/WLAN interworking is an effective way to promote the evolution of wireless networks. Interworking of Wireless LANs and Cellular Networks focuses on three aspects, namely access selection, call admission control and load sharing to investigate heterogeneous interworking for cellular/WLAN integrated networks. It not only reveals important observations but also offers useful tools for performance evaluation. The unique traffic and network characteristics are exploited to enhance interworking effectiveness. Theoretical analysis and simulation validation demonstrate benefits of cellular/WLAN interworking in real networks. Last but not the least,...

  11. Hippocampal deletion of BDNF gene attenuates gamma oscillations in area CA1 by up-regulating 5-HT3 receptor.

    Directory of Open Access Journals (Sweden)

    Ying Huang

    Full Text Available BACKGROUND: Pyramidal neurons in the hippocampal area CA3 express high levels of BDNF, but how this BDNF contributes to oscillatory properties of hippocampus is unknown. METHODOLOGY/PRINCIPAL FINDINGS: Here we examined carbachol-induced gamma oscillations in hippocampal slices lacking BDNF gene in the area CA3. The power of oscillations was reduced in the hippocampal area CA1, which coincided with increases in the expression and activity of 5-HT3 receptor. Pharmacological block of this receptor partially restored power of gamma oscillations in slices from KO mice, but had no effect in slices from WT mice. CONCLUSION/SIGNIFICANCE: These data suggest that BDNF facilitates gamma oscillations in the hippocampus by attenuating signaling through 5-HT3 receptor. Thus, BDNF modulates hippocampal oscillations through serotonergic system.

  12. Coordinated Multi-Objective Control of Regulating Resources in Multi-Area Power Systems with Large Penetration of Wind Power Generation

    DEFF Research Database (Denmark)

    Nyeng, Preben; Yang, Bo; Ma, Jian

    2008-01-01

    This paper describes a control algorithm for a Wide Area Energy Storage and Management System (WAEMS). The WAEMS is designed to meet the demand for fast, accurate and reliable regulation services in multi-area power systems with a significant share of wind power and other intermittent generation....... The means are utilization of flywheel energy storage units, hydro power generation, and energy exchange among the participating control areas. The objective of the control algorithm is to respond to the control signals from the different system operators, whilst optimizing the hydro power plant operation...... by reducing the tear and wear on the mechanical parts and improving the energy efficiency of the plant. The performance of the WAEMS is simulated using a mathematical model, including hydro power plant and flywheel energy storage models. ACE measurements from the California ISO and Bonneville Power...

  13. Physiological enzymology: The next frontier in understanding protein structure and function at the cellular level.

    Science.gov (United States)

    Lee, Irene; Berdis, Anthony J

    2016-01-01

    Historically, the study of proteins has relied heavily on characterizing the activity of a single purified protein isolated from other cellular components. This classic approach allowed scientists to unambiguously define the intrinsic kinetic and chemical properties of that protein. The ultimate hope was to extrapolate this information toward understanding how the enzyme or receptor behaves within its native cellular context. These types of detailed in vitro analyses were necessary to reduce the innate complexities of measuring the singular activity and biochemical properties of a specific enzyme without interference from other enzymes and potential competing substrates. However, recent developments in fields encompassing cell biology, molecular imaging, and chemical biology now provide the unique chemical tools and instrumentation to study protein structure, function, and regulation in their native cellular environment. These advancements provide the foundation for a new field, coined physiological enzymology, which quantifies the function and regulation of enzymes and proteins at the cellular level. In this Special Edition, we explore the area of Physiological Enzymology and Protein Function through a series of review articles that focus on the tools and techniques used to measure the cellular activity of proteins inside living cells. This article is part of a Special Issue entitled: Physiological Enzymology and Protein Functions.

  14. 33 CFR 165.540 - Regulated Navigation Area; Cape Fear River, Northeast Cape Fear River, Wilmington, North Carolina.

    Science.gov (United States)

    2010-07-01

    ..., Passing Lane & Anchorage Basin, Big Island, and the Northeast Cape Fear River. Drilling or blasting is expected to occur within the Passing Lane & Anchorage Basin, Big Island, and the Northeast Cape Fear River... Lighted Buoy 27 (LL 30550/39945)). (3) Big Island. The work area includes: Part of Keg Island...

  15. 33 CFR 165.156 - Regulated Navigation Area: East Rockaway Inlet to Atlantic Beach Bridge, Nassau County, Long...

    Science.gov (United States)

    2010-07-01

    ..., thence easterly along the shore to the east side of the Atlantic Beach Bridge, State Route 878, over East... Rockaway Inlet to Atlantic Beach Bridge, Nassau County, Long Island, New York. 165.156 Section 165.156... to Atlantic Beach Bridge, Nassau County, Long Island, New York. (a) Location. The following area is...

  16. 33 CFR 165.501 - Chesapeake Bay entrance and Hampton Roads, VA and adjacent waters-Regulated Navigation Area.

    Science.gov (United States)

    2010-07-01

    ... across the James River along the eastern side of U.S. Route 17 highway bridge, between Newport News and.... Thimble Shoal Channel consists of the waters bounded by a line connecting Thimble Shoal Channel Lighted... Auxiliary Channel consists of the waters in a rectangular area 450 feet wide adjacent to the north side...

  17. Heterogeneous cellular networks

    CERN Document Server

    Hu, Rose Qingyang

    2013-01-01

    A timely publication providing coverage of radio resource management, mobility management and standardization in heterogeneous cellular networks The topic of heterogeneous cellular networks has gained momentum in industry and the research community, attracting the attention of standardization bodies such as 3GPP LTE and IEEE 802.16j, whose objectives are looking into increasing the capacity and coverage of the cellular networks. This book focuses on recent progresses,  covering the related topics including scenarios of heterogeneous network deployment, interference management i

  18. The Customs Regulation of Export-Import Operations in the Context of the Deep and Comprehensive Free Trade Area between Ukraine and the EU

    Directory of Open Access Journals (Sweden)

    Kuzmin Oleh Ye.

    2017-05-01

    Full Text Available The article is concerned with the problems of reforming the customs regulation of export-import operations in the context of the Deep and Comprehensive Free Trade Area between Ukraine and the EU. Both the goods and the territorial structures of Ukraine’s export-import activities with the EU Member States were analyzed. Trends in the cooperation of the foreign economic actors in the Lviv region with the EU counterparts were explored. The key activities carried out in Ukraine in the sphere of customs regulation in the context of implementation of the Deep and Comprehensive Free Trade Area between Ukraine and the EU have been outlined and characterized, in particular: administration of tariff quotas, issuance of certificates by the customs authorities for the transport of EUR 1 goods, granting of the status of authorized exporter to economic entities, launching of an automated system of customs services «One-stop window», transition to electronic declaration, etc. The results, problematic issues and benefits of implementing the above activities in the sphere of customs regulation of the export-import activities of enterprises have been characterized.

  19. Modeling cellular systems

    CERN Document Server

    Matthäus, Franziska; Pahle, Jürgen

    2017-01-01

    This contributed volume comprises research articles and reviews on topics connected to the mathematical modeling of cellular systems. These contributions cover signaling pathways, stochastic effects, cell motility and mechanics, pattern formation processes, as well as multi-scale approaches. All authors attended the workshop on "Modeling Cellular Systems" which took place in Heidelberg in October 2014. The target audience primarily comprises researchers and experts in the field, but the book may also be beneficial for graduate students.

  20. Epigenetics and Cellular Metabolism

    OpenAIRE

    Wenyi Xu; Fengzhong Wang; Zhongsheng Yu; Fengjiao Xin

    2016-01-01

    Living eukaryotic systems evolve delicate cellular mechanisms for responding to various environmental signals. Among them, epigenetic machinery (DNA methylation, histone modifications, microRNAs, etc.) is the hub in transducing external stimuli into transcriptional response. Emerging evidence reveals the concept that epigenetic signatures are essential for the proper maintenance of cellular metabolism. On the other hand, the metabolite, a main environmental input, can also influence the proce...

  1. Nanostructured cellular networks.

    Science.gov (United States)

    Moriarty, P; Taylor, M D R; Brust, M

    2002-12-01

    Au nanocrystals spin-coated onto silicon from toluene form cellular networks. A quantitative statistical crystallography analysis shows that intercellular correlations drive the networks far from statistical equilibrium. Spin-coating from hexane does not produce cellular structure, yet a strong correlation is retained in the positions of nanocrystal aggregates. Mechanisms based on Marangoni convection alone cannot account for the variety of patterns observed, and we argue that spinodal decomposition plays an important role in foam formation.

  2. mRNA expression of genes regulating lipid metabolism in ringed seals (Pusa hispida) from differently polluted areas

    Energy Technology Data Exchange (ETDEWEB)

    Castelli, Martina Galatea [Norwegian Polar Institute, Fram Centre, 9296 Tromsø (Norway); University of Bergen, Department of Biology, 5020 Bergen (Norway); Rusten, Marte; Goksøyr, Anders [University of Bergen, Department of Biology, 5020 Bergen (Norway); Routti, Heli, E-mail: heli.routti@npolar.no [Norwegian Polar Institute, Fram Centre, 9296 Tromsø (Norway)

    2014-01-15

    Highlights: •Genes regulating lipid metabolism were studied in ringed seals. •We compared highly contaminated Baltic seals and less contaminated Svalbard seals. •mRNA expression of hepatic PPARγ was higher in the Baltic seals. •mRNA expression of adipose PPARγ target genes was higher in the Baltic seals. •Contaminant exposure may affect lipid metabolism in the Baltic ringed seals. -- Abstract: There is a growing concern about the ability of persistent organic pollutants (POPs) to influence lipid metabolism. Although POPs are found at high concentrations in some populations of marine mammals, for example in the ringed seal (Pusa hispida) from the Baltic Sea, little is known about the effects of POPs on their lipid metabolism. An optimal regulation of lipid metabolism is crucial for ringed seals during the fasting/molting season. This is a physiologically stressful period, during which they rely on the energy stored in their fat reserves. The mRNA expression levels for seven genes involved in lipid metabolism were analyzed in liver and/or blubber tissue from molting ringed seals from the polluted Baltic Sea and a less polluted reference location, Svalbard (Norway). mRNA expression of genes encoding peroxisome proliferator-activated receptors (PPAR) α and γ and their target genes acyl-coenzyme A oxidase 1 (ACOX1) and cluster of differentiation 36 (CD36) were analyzed in liver. mRNA expression level of genes encoding PPARβ, PPARγ and their target genes encoding fatty acid binding protein 4 (FABP4) and adiponectin (ADIPOQ) were measured in inner and middle blubber layers. In addition, we evaluated the influence of molting status on hepatic mRNA expression of genes encoding PPARs and their target genes in ringed seals from Svalbard. Our results show higher mRNA expression of genes encoding hepatic PPARγ and adipose PPARβ, FABP4, and ADIPOQ in the Baltic seals compared to the Svalbard seals. A positive relationship between mRNA expressions of genes

  3. Teachers working together to foster self-regulated learning through reading by students in an elementary school located in a disadvantaged area

    Directory of Open Access Journals (Sweden)

    Sylvie C. Cartier

    2010-12-01

    Full Text Available A key question for the educational research community concerns how teachers can adapt theories and practices supported by the scientific literature in ways that meet the particular needs of students in classrooms. The research reported here takes up that question by investigating how a team of teachers in an elementary school in a disadvantaged area built from research and theory to enact, try out, and refine classroom practices supportive of self-regulated LTR in their subject-area classrooms in light of their students’ needs. Our goals were to (1 describe what classroom activities participating teachers planned and implemented to integrate attention to the curriculum with support for self-regulated LTR; (2 evaluate the match between teachers’ practices and recommendations from the literature, as represented in the framework on which they were drawing; and (3 trace how practices enacted by teachers could be related to the perceptions and learning processes of their 123 Grade 5 and 6 students. A key finding was that teachers were successful in embedding activities into classrooms that engaged students in self-regulation, particularly use of cognitive strategies. However, we also found that the practices enacted did not sufficiently push students towards self-conscious, deliberate self-direction of learning. Implications are drawn about how classrooms practices can be constructed to take into account qualities of LTR contexts and supports necessary to foster success in school by young, at-risk learners. Discussion also focuses on benefits and challenges when teachers work together to adapt practices for use in subject area classrooms in ways that are responsive to student needs.

  4. Optimal sterile insect release for area-wide integrated pest management in a density regulated pest population.

    Science.gov (United States)

    Gordillo, Luis F

    2014-06-01

    To determine optimal sterile insect release policies in area-wide integrated pest management is a challenge that users of this pest control method inevitably confront. In this note we provide approximations to best policies of release through the use of simulated annealing. The discrete time model for the population dynamics includes the effects of sterile insect release and density dependence in the pest population. Spatial movement is introduced through integrodifference equations, which allow the use of the stochastic search in cases where movement is described through arbitrary dispersal kernels. As a byproduct of the computations, an assessment of appropriate control zone sizes is possible.

  5. [The role of histamine in regulation of spontaneous electrical activity of the rat ureter and bordering to bladder area].

    Science.gov (United States)

    Kazarian, K V; Vantsian, B Ts; Simonian, L G

    2011-12-01

    The nature of the influence of histamine on the slow wave and spike spontaneous activity of both perirenal and peribladder bordering areas of the bladder zone has been studied. It is shown that under these conditions of activated renal section of the organ, in the distal part, the decrease in frequency of the slow waves occurred. The histamine effect also contributes to improvement of the conduction of the excitation wave propagating to the bladder, which destroys the coordination of spike activity of the latter with slow waves of ureteral bordering zone.

  6. Remedial investigation plan for Waste Area Grouping 1 at Oak Ridge National Laboratory, Oak Ridge, Tennessee: Responses to regulator comments

    Energy Technology Data Exchange (ETDEWEB)

    1991-05-01

    This document, ES/ER-6 D2, is a companion document to ORNL/RAP/Sub-87/99053/4 R1, Remedial Investigation Plan for ORNL Waste Area Grouping 1, dated August 1989. This document lists comments received from the Environmental Protection Agency, Region 4 (EPA) and the Tennessee Department of Health and Environment (TDHE) and responses to each of these comments. As requested by EPA, a revised Remedial Investigation (RI) Plan for Waste Area Grouping (WAG) 1 will not be submitted. The document is divided into two Sections and Appendix. Section I contains responses to comments issued on May 22, 1990, by EPA's Region 4 program office responsible for implementing the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA). Section 2 contains responses to comments issued on April 7, 1989, by EPA's program office responsible for implementing the Resource Conservation and Recovery Act (RCRA); these comments include issues raised by the TDHE. The Appendix contains the attachments referenced in a number of the responses. 35 refs.

  7. Aging of the inceptive cellular population: the relationship between stem cells and aging.

    Science.gov (United States)

    Symonds, Catherine E; Galderisi, Umberto; Giordano, Antonio

    2009-04-02

    The average life expectancy worldwide has about doubled and the global population has increased six fold over the past century. With improving health care in the developed world there is a proportional augmentation in the treatment necessary for elderly patients occasioning the call for increased research in the area of aging and age-related diseases. The manifestation of this research has been focalized on the causative cellular processes and molecular mechanisms involved. Here we will discuss the efforts of this research in the area of stem cells, delving into the regulatory mechanisms and how their de-regulation could be attributed to aging and age-related diseases.

  8. Architected Cellular Materials

    Science.gov (United States)

    Schaedler, Tobias A.; Carter, William B.

    2016-07-01

    Additive manufacturing enables fabrication of materials with intricate cellular architecture, whereby progress in 3D printing techniques is increasing the possible configurations of voids and solids ad infinitum. Examples are microlattices with graded porosity and truss structures optimized for specific loading conditions. The cellular architecture determines the mechanical properties and density of these materials and can influence a wide range of other properties, e.g., acoustic, thermal, and biological properties. By combining optimized cellular architectures with high-performance metals and ceramics, several lightweight materials that exhibit strength and stiffness previously unachievable at low densities were recently demonstrated. This review introduces the field of architected materials; summarizes the most common fabrication methods, with an emphasis on additive manufacturing; and discusses recent progress in the development of architected materials. The review also discusses important applications, including lightweight structures, energy absorption, metamaterials, thermal management, and bioscaffolds.

  9. The site specific demethylation in the 5'-regulatory area of NMDA receptor 2B subunit gene associated with CIE-induced up-regulation of transcription.

    Directory of Open Access Journals (Sweden)

    Mei Qiang

    Full Text Available BACKGROUND: The NMDA receptor represents a particularly important site of ethanol action in the CNS. We recently reported that NMDA receptor 2B (NR2B gene expression was persistently up-regulated following chronic intermittent ethanol (CIE treatment. Increasing evidence that epigenetic mechanisms are involved in dynamic and long-lasting regulation of gene expression in multiple neuroadaptive processes prompted us to investigate the role of DNA methylation in mediating CIE-induced up-regulation of NR2B gene transcription. To dissect the changes of DNA methylation in the NR2B gene, we have screened a large number of CpG sites within its 5'-regulatory area following CIE treatment. METHODS: Primary cortical cultured neurons were subjected to ethanol treatment in a CIE paradigm. Bisulfite conversion followed by pyrosequencing was used for quantitative measurement and analysis of CpG methylation status within the 5'-regulatory area of the NR2B gene; chromatin immunoprecipitation (ChIP assay was used to examine DNA levels associated with methylation and transcription factor binding. Electrophoretic mobility shift assay (EMSA and in vitro DNA methylation assays were performed to determine the direct impact of DNA methylation on the interaction between DNA and transcription factor and promoter activity. RESULTS: Analysis of individual CpG methylation sites within the NR2B 5'regulatory area revealed three regions with clusters of site-specific CpG demethylation following CIE treatment and withdrawal. This was confirmed by ChIP showing similar decreases of methylated DNA in the same regions. The CIE-induced demethylation is characterized by being located near certain transcription factor binding sequences, AP-1 and CRE, and occurred during treatment as well as after ethanol withdrawal. Furthermore, the increase in vitro of methylated DNA decreased transcription factor binding activity and promoter activity. An additional ChIP assay indicated that the CIE

  10. Cell biology of the future: Nanometer-scale cellular cartography.

    Science.gov (United States)

    Taraska, Justin W

    2015-10-26

    Understanding cellular structure is key to understanding cellular regulation. New developments in super-resolution fluorescence imaging, electron microscopy, and quantitative image analysis methods are now providing some of the first three-dimensional dynamic maps of biomolecules at the nanometer scale. These new maps--comprehensive nanometer-scale cellular cartographies--will reveal how the molecular organization of cells influences their diverse and changeable activities.

  11. Cellular trafficking of nicotinic acetylcholine receptors

    Institute of Scientific and Technical Information of China (English)

    Paul A ST JOHN

    2009-01-01

    Nicotinic acetylcholine receptors (nAChRs) play critical roles throughout the body. Precise regulation of the cellular location and availability of nAChRs on neurons and target cells is critical to their proper function. Dynamic, post-translational regulation of nAChRs, particularly control of their movements among the different compartments of cells, is an important aspect of that regulation. A combination of new information and new techniques has the study of nAChR trafficking poised for new breakthroughs.

  12. Cellular structural biology.

    Science.gov (United States)

    Ito, Yutaka; Selenko, Philipp

    2010-10-01

    While we appreciate the complexity of the intracellular environment as a general property of every living organism, we collectively lack the appropriate tools to analyze protein structures in a cellular context. In-cell NMR spectroscopy represents a novel biophysical tool to investigate the conformational and functional characteristics of biomolecules at the atomic level inside live cells. Here, we review recent in-cell NMR developments and provide an outlook towards future applications in prokaryotic and eukaryotic cells. We hope to thereby emphasize the usefulness of in-cell NMR techniques for cellular studies of complex biological processes and for structural analyses in native environments. Copyright © 2010 Elsevier Ltd. All rights reserved.

  13. Cellular blue naevus

    Directory of Open Access Journals (Sweden)

    Mittal R

    2001-01-01

    Full Text Available A 31-year-old man had asymptomatic, stationary, 1.5X2 cm, shiny, smooth, dark blue nodule on dorsum of right hand since 12-14 years. In addition he had developed extensive eruption of yellow to orange papulonodular lesions on extensors of limbs and buttocks since one and half months. Investigations confirmed that yellow papules were xanthomatosis and he had associated diabetes mellitus and hyperlipidaemia. Biopsy of blue nodule confirmed the clinical diagnosis of cellular blue naevus. Cellular blue naevus is rare and its association with xanthomatosis and diabetes mellitus were interesting features of above patients which is being reported for its rarity.

  14. Establishment and maintenance of regulating ecosystem services in a dryland area of Central Asia: the Kökyar Protection Forest, Aksu, NW China, as an example

    Science.gov (United States)

    Missall, S.; Welp, M.; Thevs, N.; Abliz, A.; Halik, Ü.

    2014-12-01

    The city of Aksu, situated at the northern fringe of the Taklimakan Desert in the northwest of China, is exposed to periodic severe dust and sand storms. In 1986, local authorities decided to establish a peri-urban shelterbelt plantation, the so-called Kökyar Protection Forest. It was realised as a patchwork of poplar shelterbelts and orchards. The total area of the plantation reached 3800 ha in 2005. This endeavour was made possible by the annual mass mobilisation of Aksu citizens, based on the Chinese regulation of the "National Compulsory Afforestation Campaigns". Establishment costs amounted to ca. CNY 60 000 ha-1 (ca. USD 10 000 ha-1). The regulating ecosystem services provided by Kökyar Protection Forest clearly reduce dust and sand storm impacts on Aksu City. Permanent maintenance of the plantation is facilitated by leasing orchard plots to private fruit farmers. This system ensures forest tending, reduces government expenses, and provides incomes to farmers. From the perspective of the local economy, annual farming net benefits generated by Kökyar fruit farmers more than compensate annual government grants for maintenance, resulting in an overall monetary net benefit of at least CNY 10 500 ha-1 (ca. USD 1600 ha-1) on the long-term average. The intended regulating ecosystem services can thus be provided to the citizens of Aksu without payments for ecosystem services or other financial burdens. For a more complete understanding of Kökyar Protection Forest, future research should be directed towards quantifying the effect of its regulating ecosystem services, and on investigating the negative downstream consequences of its water consumption.

  15. Establishment and maintenance of regulating ecosystem services in a dryland area of Central Asia: the Kökyar Protection Forest, Aksu, NW China, as an example

    Directory of Open Access Journals (Sweden)

    S. Missall

    2014-12-01

    Full Text Available The city of Aksu, situated at the northern fringe of the Taklimakan Desert in the northwest of China, is exposed to periodic severe dust and sand storms. In 1986, local authorities decided to establish a peri-urban shelterbelt plantation, the so-called Kökyar Protection Forest. It was realised as a patchwork of poplar shelterbelts and orchards. The total area of the plantation reached 3800 ha in 2005. This endeavour was made possible by the annual mass mobilisation of Aksu citizens, based on the Chinese regulation of the "National Compulsory Afforestation Campaigns". Establishment costs amounted to ca. CNY 60 000 ha−1 (ca. USD 10 000 ha−1. The regulating ecosystem services provided by Kökyar Protection Forest clearly reduce dust and sand storm impacts on Aksu City. Permanent maintenance of the plantation is facilitated by leasing orchard plots to private fruit farmers. This system ensures forest tending, reduces government expenses, and provides incomes to farmers. From the perspective of the local economy, annual farming net benefits generated by Kökyar fruit farmers more than compensate annual government grants for maintenance, resulting in an overall monetary net benefit of at least CNY 10 500 ha−1 (ca. USD 1600 ha−1 on the long-term average. The intended regulating ecosystem services can thus be provided to the citizens of Aksu without payments for ecosystem services or other financial burdens. For a more complete understanding of Kökyar Protection Forest, future research should be directed towards quantifying the effect of its regulating ecosystem services, and on investigating the negative downstream consequences of its water consumption.

  16. The cellular decision between apoptosis and autophagy

    Institute of Scientific and Technical Information of China (English)

    Yong-Jun Fan; Wei-Xing Zong

    2013-01-01

    Apoptosis and autophagy are important molecular processes that maintain organismal and cellular homeostasis,respectively.While apoptosis fulfills its role through dismantling damaged or unwanted cells,autophagy maintains cellular homeostasis through recycling selective intracellular organelles and molecules.Yet in some conditions,autophagy can lead to cell death.Apoptosis and autophagy can be stimulated by the same stresses.Emerging evidence indicates an interplay between the core proteins in both pathways,which underlies the molecular mechanism of the crosstalk between apoptosis and autophagy.This review summarizes recent literature on molecules that regulate both the apoptotic and autophagic processes.

  17. Toxicology and cellular effect of manufactured nanomaterials

    Science.gov (United States)

    Chen, Fanqing

    2014-07-22

    The increasing use of nanotechnology in consumer products and medical applications underlies the importance of understanding its potential toxic effects to people and the environment. Herein are described methods and assays to predict and evaluate the cellular effects of nanomaterial exposure. Exposing cells to nanomaterials at cytotoxic doses induces cell cycle arrest and increases apoptosis/necrosis, activates genes involved in cellular transport, metabolism, cell cycle regulation, and stress response. Certain nanomaterials induce genes indicative of a strong immune and inflammatory response within skin fibroblasts. Furthermore, the described multiwall carbon nanoonions (MWCNOs) can be used as a therapeutic in the treatment of cancer due to its cytotoxicity.

  18. Motion Analysis of Thumb in Cellular Phone Use

    Directory of Open Access Journals (Sweden)

    Naotaka Sakai

    2010-01-01

    Full Text Available The thumb motion of 10 normal subjects during cellular phone use was measured using a reflective marker detection system to compare the maximum, minimum and range of flexion angles of the interphalangeal (IP, metacarpophalangeal (MP and carpometacarpal (CM joints. Two micro-reflective markers 3 mm in diameter were each placed on the dorsal surface of the distal phalanx, basal phalanx and metacarpal bone of the thumb. Three markers were placed on the dorsal hand in order to define the dorsal hand plane. Each subject pushed the 12 keys of a folding cellular phone with an 85-mm-long and 40-mm-wide keypad, sequentially from ‘1’ to ‘#’, and the pushing motion was recorded by six infrared video cameras for 12 seconds, using the VICON 612 system. The mean maximum flexion angle of the MP joint was significantly (p < .05 larger than the CM joint, and the mean minimum flexion angle of the CM joint was significantly (p < .01 smaller than the IP and MP joints. The mean range of motion of the IP joint was significantly (p < .05 larger than the MP and the CM joints. In a comparison of different key-pushing motions, only the CM joint was significantly (p < .05 larger in its range of motion. In conclusion, thumb motion on pushing the keys of the cellular phone was produced mainly by the MP and the CM joints. In addition, the ability to reach keys in different areas of the cellular phone keypad is regulated by changing the flexion angle of the CM joint.

  19. Cellular interactions with tissue-engineered microenvironments and nanoparticles

    Science.gov (United States)

    Pan, Zhi

    Tissue-engineered hydrogels composed of intermolecularlly crosslinked hyaluronan (HA-DTPH) and fibronectin functional domains (FNfds) were applied as a physiological relevant ECM mimic with controlled mechanical and biochemical properties. Cellular interactions with this tissue-engineered environment, especially physical interactions (cellular traction forces), were quantitatively measured by using the digital image speckle correlation (DISC) technique and finite element method (FEM). By correlating with other cell functions such as cell morphology and migration, a comprehensive structure-function relationship between cells and their environments was identified. Furthermore, spatiotemporal redistribution of cellular traction stresses was time-lapse measured during cell migration to better understand the dynamics of cell mobility. The results suggest that the reinforcement of the traction stresses around the nucleus, as well as the relaxation of nuclear deformation, are critical steps during cell migration, serving as a speed regulator, which must be considered in any dynamic molecular reconstruction model of tissue cell migration. Besides single cell migration, en masse cell migration was studied by using agarose droplet migration assay. Cell density was demonstrated to be another important parameter to influence cell behaviors besides substrate properties. Findings from these studies will provide fundamental design criteria to develop novel and effective tissue-engineered constructs. Cellular interactions with rutile and anatase TiO2 nanoparticles were also studied. These particles can penetrate easily through the cell membrane and impair cell function, with the latter being more damaging. The exposure to nanoparticles was found to decrease cell area, cell proliferation, motility, and contractility. To prevent this, a dense grafted polymer brush coating was applied onto the nanoparticle surface. These modified nanoparticles failed to adhere to and penetrate

  20. REGULATORY MECHANISMS OF CELLULAR RESPIRATION

    Science.gov (United States)

    Barron, E. S. Guzman; Nelson, Leonard; Ardao, Maria Isabel

    1948-01-01

    Oxidizing agents of sulfhydryl groups such as iodosobenzoate, alkylating agents such as iodoacetamide, and mercaptide-forming agents such as cadmium chloride, mercuric chloride, p-chloromercuribenzoate, sodium arsenite, and p-carboxyphenylarsine oxide, added in small concentrations to a suspension of sea urchin sperm produced an increase in respiration. When the concentration was increased there was an inhibition. These effects are explained by postulating the presence in the cells of two kinds of sulfhydryl groups: soluble sulfhydryl groups, which regulate cellular respiration, and fixed sulfhydryl groups, present in the protein moiety of enzymes. Small concentrations of sulfhydryl reagents combine only with the first, thus producing an increase in respiration; when the concentration is increased, the fixed sulfhydryl groups are also attacked and inhibition of respiration is the consequence. Other inhibitors of cell respiration, such as cyanide and urethanes, which do not combine with —SH groups, did not stimulate respiration in small concentration. PMID:18891144