WorldWideScience

Sample records for suppressor ptprt knockout

  1. Hepatitis B virus X protein mutant HBxΔ127 promotes proliferation of hepatoma cells through up-regulating miR-215 targeting PTPRT

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Fabao [Department of Cancer Research, College of Life Sciences, Nankai University, Tianjin 300071 (China); Department of Biochemistry, College of Life Sciences, Nankai University, Tianjin 300071 (China); You, Xiaona [Department of Cancer Research, College of Life Sciences, Nankai University, Tianjin 300071 (China); Chi, Xiumei [Department of Hepatology, The First Hospital, Jilin University, Changchun 130021 (China); Wang, Tao [Department of Cancer Research, College of Life Sciences, Nankai University, Tianjin 300071 (China); Ye, Lihong [Department of Biochemistry, College of Life Sciences, Nankai University, Tianjin 300071 (China); Niu, Junqi, E-mail: junqiniu@yahoo.com.cn [Department of Hepatology, The First Hospital, Jilin University, Changchun 130021 (China); Zhang, Xiaodong, E-mail: zhangxd@nankai.edu.cn [Department of Cancer Research, College of Life Sciences, Nankai University, Tianjin 300071 (China)

    2014-02-07

    Highlights: • Relative to wild type HBx, HBX mutant HBxΔ127 strongly enhances cell proliferation. • Relative to wild type HBx, HBxΔ127 remarkably up-regulates miR-215 in hepatoma cells. • HBxΔ127-elevated miR-215 promotes cell proliferation via targeting PTPRT mRNA. - Abstract: The mutant of virus is a frequent event. Hepatitis B virus X protein (HBx) plays a vital role in the development of hepatocellular carcinoma (HCC). Therefore, the identification of potent mutant of HBx in hepatocarcinogenesis is significant. Previously, we identified a natural mutant of the HBx gene (termed HBxΔ127). Relative to wild type HBx, HBxΔ127 strongly enhanced cell proliferation and migration in HCC. In this study, we aim to explore the mechanism of HBxΔ127 in promotion of proliferation of hepatoma cells. Our data showed that both wild type HBx and HBxΔ127 could increase the expression of miR-215 in hepatoma HepG2 and H7402 cells. However, HBxΔ127 was able to significantly increase miR-215 expression relative to wild type HBx in the cells. We identified that protein tyrosine phosphatase, receptor type T (PTPRT) was one of the target genes of miR-215 through targeting 3′UTR of PTPRT mRNA. In function, miR-215 was able to promote the proliferation of hepatoma cells. Meanwhile anti-miR-215 could partially abolish the enhancement of cell proliferation mediated by HBxΔ127 in vitro. Knockdown of PTPRT by siRNA could distinctly suppress the decrease of cell proliferation mediated by anti-miR-215 in HepG2-XΔ127/H7402-XΔ127 cells. Moreover, we found that anti-miR-215 remarkably inhibited the tumor growth of hepatoma cells in nude mice. Collectively, relative to wild type HBx, HBxΔ127 strongly enhances proliferation of hepatoma cells through up-regulating miR-215 targeting PTPRT. Our finding provides new insights into the mechanism of HBx mutant HBxΔ127 in promotion of proliferation of hepatoma cells.

  2. Tumor suppressors: enhancers or suppressors of regeneration?

    Science.gov (United States)

    Pomerantz, Jason H.; Blau, Helen M.

    2013-01-01

    Tumor suppressors are so named because cancers occur in their absence, but these genes also have important functions in development, metabolism and tissue homeostasis. Here, we discuss known and potential functions of tumor suppressor genes during tissue regeneration, focusing on the evolutionarily conserved tumor suppressors pRb1, p53, Pten and Hippo. We propose that their activity is essential for tissue regeneration. This is in contrast to suggestions that tumor suppression is a trade-off for regenerative capacity. We also hypothesize that certain aspects of tumor suppressor pathways inhibit regenerative processes in mammals, and that transient targeted modification of these pathways could be fruitfully exploited to enhance processes that are important to regenerative medicine. PMID:23715544

  3. The Knockout Mouse Project

    Science.gov (United States)

    Austin, Christopher P; Battey, James F; Bradley, Allan; Bucan, Maja; Capecchi, Mario; Collins, Francis S; Dove, William F; Duyk, Geoffrey; Dymecki, Susan; Eppig, Janan T; Grieder, Franziska B; Heintz, Nathaniel; Hicks, Geoff; Insel, Thomas R; Joyner, Alexandra; Koller, Beverly H; Lloyd, K C Kent; Magnuson, Terry; Moore, Mark W; Nagy, Andras; Pollock, Jonathan D; Roses, Allen D; Sands, Arthur T; Seed, Brian; Skarnes, William C; Snoddy, Jay; Soriano, Philippe; Stewart, David J; Stewart, Francis; Stillman, Bruce; Varmus, Harold; Varticovski, Lyuba; Verma, Inder M; Vogt, Thomas F; von Melchner, Harald; Witkowski, Jan; Woychik, Richard P; Wurst, Wolfgang; Yancopoulos, George D; Young, Stephen G; Zambrowicz, Brian

    2009-01-01

    Mouse knockout technology provides a powerful means of elucidating gene function in vivo, and a publicly available genome-wide collection of mouse knockouts would be significantly enabling for biomedical discovery. To date, published knockouts exist for only about 10% of mouse genes. Furthermore, many of these are limited in utility because they have not been made or phenotyped in standardized ways, and many are not freely available to researchers. It is time to harness new technologies and efficiencies of production to mount a high-throughput international effort to produce and phenotype knockouts for all mouse genes, and place these resources into the public domain. PMID:15340423

  4. Cluster knockout reactions

    Indian Academy of Sciences (India)

    2014-04-07

    Apr 7, 2014 ... advancements in the area of (α, 2α) reactions and heavy cluster knockout reactions are discussed. Importance of the finite-range vertex and the final-state interactions are brought out. Keywords. Cluster knockout reactions; FR-DWIA calculations; t-matrix effective interaction. PACS Nos 14.20.Pt; 24.10.

  5. Cluster knockout reactions

    Indian Academy of Sciences (India)

    2014-04-07

    Apr 7, 2014 ... Cluster knockout reactions are expected to reveal the amount of clustering (such as that of , d and even of heavier clusters such as 12C, 16O etc.) in the target nucleus. In simple terms, incident medium high-energy nuclear projectile interacts strongly with the cluster (present in the target nucleus) as if it ...

  6. KnockoutJS blueprints

    CERN Document Server

    Russo, Carlo

    2015-01-01

    If you are a JavaScript developer and already know the basics of KnockoutJS and you want to get the most out of it, then this book is for you. This book will help in your transition from a small site to a large web application that is easily maintainable.

  7. KnockoutJS essentials

    CERN Document Server

    Ferrando, Jorge

    2015-01-01

    If you are a JavaScript developer who has been using DOM manipulation libraries such as Mootools or Scriptaculous, and you want go further in modern JavaScript development with a simple and well-documented library, then this book is for you. Learning how to use Knockout will be perfect as your next step towards building JavaScript applications that respond to user interaction.

  8. Cluster knockout reactions

    Indian Academy of Sciences (India)

    2014-04-07

    Apr 7, 2014 ... (figure 2), the corresponding α–α t-matrix effective interactions are seen to be widely different (figure 3). 2. Formalism. The finite-range transition matrix element T n,l. BA in the triple differential cross-section [13], d3σ d 1d 2dE1. = Fkin × Sl × |T n,l. BA (kf 1, kf 2, ki)|2 for the (α, 2α) cluster knockout reactions is ...

  9. Tumor suppressor molecules and methods of use

    Science.gov (United States)

    Welch, Peter J.; Barber, Jack R.

    2004-09-07

    The invention provides substantially pure tumor suppressor nucleic acid molecules and tumor suppressor polypeptides. The invention also provides hairpin ribozymes and antibodies selective for these tumor suppressor molecules. Also provided are methods of detecting a neoplastic cell in a sample using detectable agents specific for the tumor suppressor nucleic acids and polypeptides.

  10. KnockoutJS web development

    CERN Document Server

    Farrar, John

    2015-01-01

    This book is for web developers and designers who work with HTML and JavaScript to help them manage data and interactivity with data using KnockoutJS. Knowledge about jQuery will be useful but is not necessary.

  11. Noise suppressor for turbo fan jet engines

    Science.gov (United States)

    Cheng, D. Y. (Inventor)

    1983-01-01

    A noise suppressor is disclosed for installation on the discharge or aft end of a turbo fan engine. Within the suppressor are fixed annular airfoils which are positioned to reduce the relative velocity between the high temperature fast moving jet exhaust and the low temperature slow moving air surrounding it. Within the suppressor nacelle is an exhaust jet nozzle which constrains the shape of the jet exhaust to a substantially uniform elongate shape irrespective of the power setting of the engine. Fixed ring airfoils within the suppressor nacelle therefore have the same salutary effects irrespective of the power setting at which the engine is operated.

  12. Suppressors made from intermetallic materials

    Science.gov (United States)

    Klett, James W; Muth, Thomas R; Cler, Dan L

    2014-11-04

    Disclosed are several examples of apparatuses for suppressing the blast and flash produced as a projectile is expelled by gases from a firearm. In some examples, gases are diverted away from the central chamber to an expansion chamber by baffles. The gases are absorbed by the expansion chamber and desorbed slowly, thus decreasing pressure and increasing residence time of the gases. In other examples, the gases impinge against a plurality of rods before expanding through passages between the rods to decrease the pressure and increase the residence time of the gases. These and other exemplary suppressors are made from an intermetallic material composition for enhanced strength and oxidation resistance at high operational temperatures.

  13. The serotonin transporter knockout rat : A review

    NARCIS (Netherlands)

    Olivier, Jocelien; Cools, Alexander; Ellenbroek, Bart A.; Cuppen, E.; Homberg, Judith; Kalueff, Allan V.; LaPorte, Justin L.

    2010-01-01

    This chapter dicusses the most recent data on the serotonin transporter knock-out rat, a unique rat model that has been generated by target-selected N-ethyl-N-nitrosourea (ENU) driven mutagenesis. The knock-out rat is the result of a premature stopcodon in the serotonin transporter gene, and the

  14. Tumor-derived exosomes induce CD8+T cell suppressors.

    Science.gov (United States)

    Maybruck, Brian T; Pfannenstiel, Lukas W; Diaz-Montero, Marcela; Gastman, Brian R

    2017-08-15

    The suppressive nature of immune cells in the tumor microenvironment plays a major role in regulating anti-tumor immune responses. Our previous work demonstrated that a soluble factor from tumor cells is able to induce a suppressor phenotype (SP) in human CD8 + T cells typified by loss of CD27/CD28 expression and acquisition of a potent suppressor function. The present study hypothesized that the soluble mechanism that is inducing the SP in CD8 + T cells are tumor-derived exosomes (TDEs). Membrane vesicles and TDEs from multiple head and neck cancer cell line's conditioned growth media were isolated by ultracentrifugation and precipitation, respectively. Human purified CD3 + CD8 + T cells were assessed for their induction of the T cell SP by flow cytometry identifying loss of CD27/CD28 expression and in vitro suppression assays. Furthermore, the T cell SP was characterized for the attenuation of IFN-γ production. To delineate exosomal proteins contributing to T cell SP, mass spectrometry was used to identify unique proteins that were present in TDEs. CRISPR/Cas9 knockout constructs were used to examine the role of one of these proteins, galectin-1. To assess the role of exosomal RNA, RNA purified from TDEs was nucleofected into CD8 + T cells followed by suppression analysis. Using fractionated conditioned growth media, factors >200 kDa induced CD8 + T cell SP, which was determined to be an exosome by mass spectrometry analysis. Multiple head and neck cancer-derived cell lines were found to secrete T cell SP-inducing exosomes. Mass spectrometry analysis revealed that an immunoregulatory protein, galectin-1 (Gal-1), was expressed in those exosomes, but not in TDEs unable to induce T cell SP. Galectin-1 knockout cells were found to be less able to induce T cell SP. Furthermore, RNA purified from the T cell SP-inducing exosomes were found to partially induce the SP when transfected into normal CD8 + T cells. For the first-time, TDEs have been identified to induce a

  15. Sdhd and SDHD/H19 knockout mice do not develop paraganglioma or pheochromocytoma.

    Directory of Open Access Journals (Sweden)

    Jean-Pierre Bayley

    Full Text Available BACKGROUND: Mitochondrial succinate dehydrogenase (SDH is a component of both the tricarboxylic acid cycle and the electron transport chain. Mutations of SDHD, the first protein of intermediary metabolism shown to be involved in tumorigenesis, lead to the human tumors paraganglioma (PGL and pheochromocytoma (PC. SDHD is remarkable in showing an 'imprinted' tumor suppressor phenotype. Mutations of SDHD show a very high penetrance in man and we postulated that knockout of Sdhd would lead to the development of PGL/PC, probably in aged mice. METHODOLOGY/PRINCIPAL FINDINGS: We generated a conventional knockout of Sdhd in the mouse, removing the entire third exon. We also crossed this mouse with a knockout of H19, a postulated imprinted modifier gene of Sdhd tumorigenesis, to evaluate if loss of these genes together would lead to the initiation or enhancement of tumor development. Homozygous knockout of Sdhd results in embryonic lethality. No paraganglioma or other tumor development was seen in Sdhd KO mice followed for their entire lifespan, in sharp contrast to the highly penetrant phenotype in humans. Heterozygous Sdhd KO mice did not show hyperplasia of paraganglioma-related tissues such as the carotid body or of the adrenal medulla, or any genotype-related pathology, with similar body and organ weights to wildtype mice. A cohort of Sdhd/H19 KO mice developed several cases of profound cardiac hypertrophy, but showed no evidence of PGL/PC. CONCLUSIONS: Knockout of Sdhd in the mouse does not result in a disease phenotype. H19 may not be an initiator of PGL/PC tumorigenesis.

  16. Generation of RUNX3 knockout pigs using CRISPR/Cas9-mediated gene targeting.

    Science.gov (United States)

    Kang, J-T; Ryu, J; Cho, B; Lee, E-J; Yun, Y-J; Ahn, S; Lee, J; Ji, D-Y; Lee, K; Park, K-W

    2016-12-01

    Pigs are an attractive animal model to study the progression of cancer because of their anatomical and physiological similarities to human. However, the use of pig models for cancer research has been limited by availability of genetically engineered pigs which can recapitulate human cancer progression. Utilizing genome editing technologies such as CRISPR/Cas9 system allows us to generate genetically engineered pigs at a higher efficiency. In this study, specific CRISPR/Cas9 systems were used to target RUNX3, a known tumour suppressor gene, to generate a pig model that can induce gastric cancer in human. First, RUNX3 knockout cell lines carrying genetic modification (monoallelic or biallelic) of RUNX3 were generated by introducing engineered CRISPR/Cas9 system specific to RUNX3 into foetal fibroblast cells. Then, the genetically modified foetal fibroblast cells were used as donor cells for somatic cell nuclear transfer, followed by embryo transfer. We successfully obtained four live RUNX3 knockout piglets from two surrogates. The piglets showed the lack of RUNX3 protein in their internal organ system. Our results demonstrate that the CRISPR/Cas9 system is effective in inducing mutations on a specific locus of genome and the RUNX3 knockout pigs can be useful resources for human cancer research and to develop novel cancer therapies. © 2016 Blackwell Verlag GmbH.

  17. Generation of two H1 hESC sublines carrying a heterozygous and homozygous knock-out of RB1

    Directory of Open Access Journals (Sweden)

    Laura Steenpass

    2017-12-01

    Full Text Available Retinoblastoma is a childhood cancer of the retina caused by biallelic inactivation of the tumor suppressor gene RB1. In heritable retinoblastoma, one allele is inherited in mutant form via one of the parental germ cells. To study molecular mechanisms in retinoblastoma, two sublines of H1 hESCs were generated, carrying a knock-out allele of RB1 in the heterozygous or homozygous state. Exon 3 of RB1 was targeted and modified by nucleotide deletions using the CRISPR/Cas9 nuclease system. Based on a nearby single nucleotide polymorphism, the modification could be assigned to one allele.

  18. Nucleon knockout: off-shell effects

    International Nuclear Information System (INIS)

    Stephenson, G.J. Jr.

    1977-01-01

    The effect of the off-energy-shell extrapolation of the proton-proton scattering amplitude on the analysis of (p,2p) reactions is discussed. In particular, the range of expected variations in this extrapolation is explored and the possibility of using knock-out reactions to limit models of the p-p amplitude is studied

  19. Tumor suppressor identified as inhibitor of inflammation

    Science.gov (United States)

    Scientists at NCI have found that a protein, FBXW7, which acts as a tumor suppressor, is also important for the reduction in strength of inflammatory pathways. It has long been recognized that a complex interaction exists between cancer causing mechanisms

  20. RNAi suppressors encoded by pathogenic human viruses

    NARCIS (Netherlands)

    de Vries, Walter; Berkhout, Ben

    2008-01-01

    RNA silencing or RNAi interference (RNAi) serves as an innate antiviral mechanism in plants, fungi and animals. Human viruses, like plant viruses, encode suppressor proteins or RNAs that block or modulate the RNAi pathway. This review summarizes the mechanisms by which pathogenic human viruses

  1. Synthetic lethal interaction between the tumour suppressor STAG2 and its paralog STAG1.

    Science.gov (United States)

    Benedetti, Lorena; Cereda, Matteo; Monteverde, LeeAnn; Desai, Nikita; Ciccarelli, Francesca D

    2017-06-06

    Cohesin is a multi-protein complex that tethers sister chromatids during mitosis and mediates DNA repair, genome compartmentalisation and regulation of gene expression. Cohesin subunits frequently acquire cancer loss-of-function alterations and act as tumour suppressors in several tumour types. This has led to increased interest in cohesin as potential target in anti-cancer therapy. Here we show that the loss-of-function of STAG2, a core component of cohesin and an emerging tumour suppressor, leads to synthetic dependency of mutated cancer cells on its paralog STAG1. STAG1 and STAG2 share high sequence identity, encode mutually exclusive cohesin subunits and retain partially overlapping functions. We inhibited STAG1 and STAG2 in several cancer cell lines where the two genes have variable mutation and copy number status. In all cases, we observed that the simultaneous blocking of STAG1 and STAG2 significantly reduces cell proliferation. We further confirmed the synthetic lethal interaction developing a vector-free CRISPR system to induce STAG1/STAG2 double gene knockout. We provide strong evidence that STAG1 is a promising therapeutic target in cancers with inactivating alterations of STAG2.

  2. Universal statistics of the knockout tournament

    Science.gov (United States)

    Baek, Seung Ki; Yi, Il Gu; Park, Hye Jin; Kim, Beom Jun

    2013-11-01

    We study statistics of the knockout tournament, where only the winner of a fixture progresses to the next. We assign a real number called competitiveness to each contestant and find that the resulting distribution of prize money follows a power law with an exponent close to unity if the competitiveness is a stable quantity and a decisive factor to win a match. Otherwise, the distribution is found narrow. The existing observation of power law distributions in various kinds of real sports tournaments therefore suggests that the rules of those games are constructed in such a way that it is possible to understand the games in terms of the contestants' inherent characteristics of competitiveness.

  3. High-throughput knockout screen in fission yeast

    OpenAIRE

    Gregan, Juraj; Rabitsch, Peter K; Rumpf, Cornelia; Novatchkova, Maria; Schleiffer, Alexander; Nasmyth, Kim

    2006-01-01

    We have designed the most efficient strategy to knock out genes in fission yeast Schizosaccharomyces pombe on a large scale. Our technique is based on knockout constructs that contain regions homologous to the target gene cloned into vectors carrying dominant drug-resistance markers. Most of the steps are carried out in a 96-well format, allowing simultaneous deletion of 96 genes in one batch. Based on our knockout technique, we designed a strategy for cloning knockout constructs for all pred...

  4. Protease activity of legumain is inhibited by an increase of cystatin E/M in the DJ-1-knockout mouse spleen, cerebrum and heart

    Directory of Open Access Journals (Sweden)

    Takuya Yamane

    2017-03-01

    Full Text Available Legumain (EC 3.4.22.34 is an asparaginyl endopeptidase. Legumain activity has been detected in various mouse tissues including the kidney, spleen and epididymis. Legumain is overexpressed in the majority of human solid tumors and transcription of the legumain gene is regulated by the p53 tumor suppressor in HCT116 cells. The legumain activity is also increased under acid conditions in Alzheimer's disease brains. DJ-1/PARK7, a cancer- and Parkinson's disease-associated protein, works as a coactivator to various transcription factors, including the androgen receptor, p53, PSF, Nrf2, SREBP and RREB1. Recently, we found that legumain expression, activation and cleavage of annexin A2 are regulated by DJ-1 through p53. In this study, we found that the expression levels of legumain mRNA were increased in the cerebrum, kidney, spleen, heart, lung, epididymis, stomach, small intestine and pancreas from DJ-1-knockout mice, although legumain activity levels were decreased in the cerebrum, spleen and heart from DJ-1-knockout mice. Furthermore, we found that cystatin E/M expression was increased in the spleen, cerebrum and heart from DJ-1-knockout mice. These results suggest that reduction of legumain activity is caused by an increase of cystatin E/M expression in the spleen, cerebrum and heart from DJ-1-knockout mice.

  5. The Tumor Suppressor Gene, RASSF1A, Is Essential for Protection against Inflammation -Induced Injury

    Science.gov (United States)

    Fiteih, Yahya; Law, Jennifer; Volodko, Natalia; Mohamed, Anwar; El-Kadi, Ayman O. S.; Liu, Lei; Odenbach, Jeff; Thiesen, Aducio; Onyskiw, Christina; Ghazaleh, Haya Abu; Park, Jikyoung; Lee, Sean Bong; Yu, Victor C.; Fernandez-Patron, Carlos; Alexander, R. Todd; Wine, Eytan; Baksh, Shairaz

    2013-01-01

    Ras association domain family protein 1A (RASSF1A) is a tumor suppressor gene silenced in cancer. Here we report that RASSF1A is a novel regulator of intestinal inflammation as Rassf1a+/−, Rassf1a−/− and an intestinal epithelial cell specific knockout mouse (Rassf1a IEC-KO) rapidly became sick following dextran sulphate sodium (DSS) administration, a chemical inducer of colitis. Rassf1a knockout mice displayed clinical symptoms of inflammatory bowel disease including: increased intestinal permeability, enhanced cytokine/chemokine production, elevated nuclear factor of kappa light polypeptide gene enhancer in B-cells (NFκB) activity, elevated colonic cell death and epithelial cell injury. Furthermore, epithelial restitution/repair was inhibited in DSS-treated Rassf1a−/− mice with reduction of several makers of proliferation including Yes associated protein (YAP)-driven proliferation. Surprisingly, tyrosine phosphorylation of YAP was detected which coincided with increased nuclear p73 association, Bax-driven epithelial cell death and p53 accumulation resulting in enhanced apoptosis and poor survival of DSS-treated Rassf1a knockout mice. We can inhibit these events and promote the survival of DSS-treated Rassf1a knockout mice with intraperitoneal injection of the c-Abl and c-Abl related protein tyrosine kinase inhibitor, imatinib/gleevec. However, p53 accumulation was not inhibited by imatinib/gleevec in the Rassf1a−/− background which revealed the importance of p53-dependent cell death during intestinal inflammation. These observations suggest that tyrosine phosphorylation of YAP (to drive p73 association and up-regulation of pro-apoptotic genes such as Bax) and accumulation of p53 are consequences of inflammation-induced injury in DSS-treated Rassf1a−/− mice. Mechanistically, we can detect robust associations of RASSF1A with membrane proximal Toll-like receptor (TLR) components to suggest that RASSF1A may function to interfere and restrict TLR

  6. Suppressors of RNA silencing encoded by tomato leaf curl ...

    Indian Academy of Sciences (India)

    2013-01-06

    Jan 6, 2013 ... satellite DNA β which are predicted to function as silencing suppressors. In the present study suppressor function ... of plant viruses with circular single-stranded DNA genomes that are composed of one or two components of ..... 1 2 3 4 5 6 7 8 9 10 11 12 13 14 M. Figure 4. Southern blot analysis of DNA ...

  7. Pion-induced knock-out reactions

    International Nuclear Information System (INIS)

    Jain, B.K.; Phatak, S.C.

    1977-01-01

    A strong absorption model for pion-induced Knock-out reactions is proposed. The distortion of the in-coming and out-going pions has been included by (1) computing pion wave number in nuclear medium (dispersive effect) and (2) excluding the central region of the nucleus where the real pion-absorption is dominant (absorption effect). In order to study the dependence of the (π + π + p) reaction on the off-shell pion-nucleon t-matrix, different off-shell extrapolations are used. The magnitude of the cross-sections seems to be sensitive to the type of off-shell extrapolation; their shapes, however, are similar. The theoretical results are compared with experimental data. The agreement between the theoretical results for separable off-shell extrapolation and the data is good. (author)

  8. Interrater agreement of an observational tool to code knockouts and technical knockouts in mixed martial arts.

    Science.gov (United States)

    Lawrence, David W; Hutchison, Michael G; Cusimano, Michael D; Singh, Tanveer; Li, Luke

    2014-09-01

    Interrater agreement evaluation of a tool to document and code the situational factors and mechanisms of knockouts (KOs) and technical knockouts (TKOs) in mixed martial arts (MMA). Retrospective case series. Professional MMA matches from the Ultimate Fighting Championship-2006-2012. Two nonmedically trained independent raters. The MMA Knockout Tool (MMA-KT) consists of 20 factors and captures and codes information on match characteristics, situational context preceding KOs and TKOs, as well as describing competitor states during these outcomes. The MMA-KT also evaluates the mechanism of action and subsequent events surrounding a KO. The 2 raters coded 125 unique events for a total of 250 events. The 8 factors of Part A had an average κ of 0.87 (SD = 0.10; range = 0.65-0.98); 7 were considered "substantial" agreement and 1 "moderate." Part B consists of 12 factors with an average κ of 0.84 (SD = 0.16; range = 0.59-1.0); 7 classified as "substantial" agreement, 4 "moderate," and 1 "fair." The majority of the factors in the MMA-KT demonstrated substantial interrater agreement, with an average κ of 0.86 (SD = 0.13; range = 0.59-1.0). The MMA-KT is a reliable tool to extract and code relevant information to investigate the situational factors and mechanism of KOs and TKOs in MMA competitions.

  9. Deciphering the BRCA1 Tumor Suppressor Network*

    Science.gov (United States)

    Jiang, Qinqin; Greenberg, Roger A.

    2015-01-01

    The BRCA1 tumor suppressor protein is a central constituent of several distinct macromolecular protein complexes that execute homology-directed DNA damage repair and cell cycle checkpoints. Recent years have borne witness to an exciting phase of discovery at the basic molecular level for how this network of DNA repair proteins acts to maintain genome stability and suppress cancer. The clinical dividends of this investment are now being realized with the approval of first-in-class BRCA-targeted therapies for ovarian cancer and identification of molecular events that determine responsiveness to these agents. Further delineation of the basic science underlying BRCA network function holds promise to maximally exploit genome instability for hereditary and sporadic cancer therapy. PMID:26048987

  10. Microbial Regulation of p53 Tumor Suppressor.

    Directory of Open Access Journals (Sweden)

    Alexander I Zaika

    2015-09-01

    Full Text Available p53 tumor suppressor has been identified as a protein interacting with the large T antigen produced by simian vacuolating virus 40 (SV40. Subsequent research on p53 inhibition by SV40 and other tumor viruses has not only helped to gain a better understanding of viral biology, but also shaped our knowledge of human tumorigenesis. Recent studies have found, however, that inhibition of p53 is not strictly in the realm of viruses. Some bacterial pathogens also actively inhibit p53 protein and induce its degradation, resulting in alteration of cellular stress responses. This phenomenon was initially characterized in gastric epithelial cells infected with Helicobacter pylori, a bacterial pathogen that commonly infects the human stomach and is strongly linked to gastric cancer. Besides H. pylori, a number of other bacterial species were recently discovered to inhibit p53. These findings provide novel insights into host-bacteria interactions and tumorigenesis associated with bacterial infections.

  11. Generation and characterization of mice carrying a conditional allele of the Wwox tumor suppressor gene.

    Directory of Open Access Journals (Sweden)

    John H Ludes-Meyers

    2009-11-01

    Full Text Available WWOX, the gene that spans the second most common human chromosomal fragile site, FRA16D, is inactivated in multiple human cancers and behaves as a suppressor of tumor growth. Since we are interested in understanding WWOX function in both normal and cancer tissues we generated mice harboring a conditional Wwox allele by flanking Exon 1 of the Wwox gene with LoxP sites. Wwox knockout (KO mice were developed by breeding with transgenic mice carrying the Cre-recombinase gene under the control of the adenovirus EIIA promoter. We found that Wwox KO mice suffered from severe metabolic defect(s resulting in growth retardation and all mice died by 3 wk of age. All Wwox KO mice displayed significant hypocapnia suggesting a state of metabolic acidosis. This finding and the known high expression of Wwox in kidney tubules suggest a role for Wwox in acid/base balance. Importantly, Wwox KO mice displayed histopathological and hematological signs of impaired hematopoiesis, leukopenia, and splenic atrophy. Impaired hematopoiesis can also be a contributing factor to metabolic acidosis and death. Hypoglycemia and hypocalcemia was also observed affecting the KO mice. In addition, bone metabolic defects were evident in Wwox KO mice. Bones were smaller and thinner having reduced bone volume as a consequence of a defect in mineralization. No evidence of spontaneous neoplasia was observed in Wwox KO mice. We have generated a new mouse model to inactivate the Wwox tumor suppressor gene conditionally. This will greatly facilitate the functional analysis of Wwox in adult mice and will allow investigating neoplastic transformation in specific target tissues.

  12. Sleep in Kcna2 knockout mice

    Directory of Open Access Journals (Sweden)

    Messing Albee

    2007-10-01

    Full Text Available Abstract Background Shaker codes for a Drosophila voltage-dependent potassium channel. Flies carrying Shaker null or hypomorphic mutations sleep 3–4 h/day instead of 8–14 h/day as their wild-type siblings do. Shaker-like channels are conserved across species but it is unknown whether they affect sleep in mammals. To address this issue, we studied sleep in Kcna2 knockout (KO mice. Kcna2 codes for Kv1.2, the alpha subunit of a Shaker-like voltage-dependent potassium channel with high expression in the mammalian thalamocortical system. Results Continuous (24 h electroencephalograph (EEG, electromyogram (EMG, and video recordings were used to measure sleep and waking in Kcna2 KO, heterozygous (HZ and wild-type (WT pups (P17 and HZ and WT adult mice (P67. Sleep stages were scored visually based on 4-s epochs. EEG power spectra (0–20 Hz were calculated on consecutive 4-s epochs. KO pups die by P28 due to generalized seizures. At P17 seizures are either absent or very rare in KO pups ( Conclusion Kv1.2, a mammalian homologue of Shaker, regulates neuronal excitability and affects NREM sleep.

  13. Regulation of the Tumor Suppressor Protein PTEN by Phosphorylation

    National Research Council Canada - National Science Library

    Vasquez, Fancisca

    2001-01-01

    The purpose of the research project of this grant is to study the role of phosphorylation on the regulation of PTEN, a tumor suppressor localized on a chromosome region frequently deleted in various...

  14. PTEN, a Tumor Suppressor Gene for Prostate Cancer

    National Research Council Canada - National Science Library

    Ittmann, Michael

    1999-01-01

    .... The PTEN gene is a tumor suppressor gene recently cloned from human chromosome 10q23.3 that encodes a lipid phosphatase which influences a variety of cellular processes that impact on the neoplastic phenotype...

  15. Regulation of the Tumor Suppressor Protein PTEN by Phosphorylation

    National Research Council Canada - National Science Library

    Vazquez, Francisca

    2000-01-01

    The purpose of the research project of this grant is to study the role of phosphorylation on the regulation of PTEN, a tumor suppressor localized on a chromosome region frequently deleted in various...

  16. Tumor suppressors status in cancer cell line Encyclopedia.

    Science.gov (United States)

    Sonkin, Dmitriy; Hassan, Mehedi; Murphy, Denis J; Tatarinova, Tatiana V

    2013-08-01

    Tumor suppressors play a major role in the etiology of human cancer, and typically achieve a tumor-promoting effect upon complete functional inactivation. Bi-allelic inactivation of tumor suppressors may occur through genetic mechanisms (such as loss of function mutation, copy number (CN) loss, or loss of heterozygosity (LOH)), epigenetic mechanisms (such as promoter methylation or histone modification), or a combination of the two. We report systematically derived status of 69 known or putative tumor suppressors, across 799 samples of the Cancer Cell Line Encyclopedia. In order to generate such resource we constructed a novel comprehensive computational framework for the assessment of tumor suppressor functional "status". This approach utilizes several orthogonal genomic data types, including mutation data, copy number, LOH and expression. Through correlation with additional data types (compound sensitivity and gene set activity) we show that this integrative method provides a more accurate assessment of tumor suppressor status than can be inferred by expression, copy number, or mutation alone. This approach has the potential for a more realistic assessment of tumor suppressor genes for both basic and translational oncology research. Copyright © 2013 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

  17. CCR5 is a suppressor for cortical plasticity and hippocampal learning and memory

    Science.gov (United States)

    Zhou, Miou; Greenhill, Stuart; Huang, Shan; Silva, Tawnie K; Sano, Yoshitake; Wu, Shumin; Cai, Ying; Nagaoka, Yoshiko; Sehgal, Megha; Cai, Denise J; Lee, Yong-Seok; Fox, Kevin; Silva, Alcino J

    2016-01-01

    Although the role of CCR5 in immunity and in HIV infection has been studied widely, its role in neuronal plasticity, learning and memory is not understood. Here, we report that decreasing the function of CCR5 increases MAPK/CREB signaling, long-term potentiation (LTP), and hippocampus-dependent memory in mice, while neuronal CCR5 overexpression caused memory deficits. Decreasing CCR5 function in mouse barrel cortex also resulted in enhanced spike timing dependent plasticity and consequently, dramatically accelerated experience-dependent plasticity. These results suggest that CCR5 is a powerful suppressor for plasticity and memory, and CCR5 over-activation by viral proteins may contribute to HIV-associated cognitive deficits. Consistent with this hypothesis, the HIV V3 peptide caused LTP, signaling and memory deficits that were prevented by Ccr5 knockout or knockdown. Overall, our results demonstrate that CCR5 plays an important role in neuroplasticity, learning and memory, and indicate that CCR5 has a role in the cognitive deficits caused by HIV. DOI: http://dx.doi.org/10.7554/eLife.20985.001 PMID:27996938

  18. Impaired caudal fin-fold regeneration in zebrafish deficient for the tumor suppressor Pten.

    Science.gov (United States)

    Hale, Alexander James; Kiai, Ali; Sikkens, Jelte; den Hertog, Jeroen

    2017-08-01

    Zebrafish are able to completely regrow their caudal fin-folds after amputation. Following injury, wound healing occurs, followed by the formation of a blastema, which produces cells to replace the lost tissue in the final phase of regenerative outgrowth. Here we show that, surprisingly, the phosphatase and tumor suppressor Pten, an antagonist of phosphoinositide-3-kinase (PI3K) signaling, is required for zebrafish caudal fin-fold regeneration. We found that homozygous knock-out mutant ( ptena -/- ptenb -/- ) zebrafish embryos, lacking functional Pten, did not regenerate their caudal fin-folds. AKT phosphorylation was enhanced, which is consistent with the function of Pten. Reexpression of Pten, but not catalytically inactive mutant Pten-C124S, rescued regeneration, as did pharmacological inhibition of PI3K. Blastema formation, determined by in situ hybridization for the blastema marker junbb , appeared normal upon caudal fin-fold amputation of ptena -/- ptenb -/- zebrafish embryos. Whole-mount immunohistochemistry using specific markers indicated that proliferation was arrested in embryos lacking functional Pten, and that apoptosis was enhanced. Together, these results suggest a critical role for Pten by limiting PI3K signaling during the regenerative outgrowth phase of zebrafish caudal fin-fold regeneration.

  19. CCR5 is a suppressor for cortical plasticity and hippocampal learning and memory.

    Science.gov (United States)

    Zhou, Miou; Greenhill, Stuart; Huang, Shan; Silva, Tawnie K; Sano, Yoshitake; Wu, Shumin; Cai, Ying; Nagaoka, Yoshiko; Sehgal, Megha; Cai, Denise J; Lee, Yong-Seok; Fox, Kevin; Silva, Alcino J

    2016-12-20

    Although the role of CCR5 in immunity and in HIV infection has been studied widely, its role in neuronal plasticity, learning and memory is not understood. Here, we report that decreasing the function of CCR5 increases MAPK/CREB signaling, long-term potentiation (LTP), and hippocampus-dependent memory in mice, while neuronal CCR5 overexpression caused memory deficits. Decreasing CCR5 function in mouse barrel cortex also resulted in enhanced spike timing dependent plasticity and consequently, dramatically accelerated experience-dependent plasticity. These results suggest that CCR5 is a powerful suppressor for plasticity and memory, and CCR5 over-activation by viral proteins may contribute to HIV-associated cognitive deficits. Consistent with this hypothesis, the HIV V3 peptide caused LTP, signaling and memory deficits that were prevented by Ccr5 knockout or knockdown. Overall, our results demonstrate that CCR5 plays an important role in neuroplasticity, learning and memory, and indicate that CCR5 has a role in the cognitive deficits caused by HIV.

  20. KF-1 ubiquitin ligase: anxiety suppressor model.

    Science.gov (United States)

    Hashimoto-Gotoh, Tamotsu; Iwabe, Naoyuki; Tsujimura, Atsushi; Nakagawa, Masanori; Marunaka, Yoshinori

    2011-06-01

    Anxiety disorders are the most popular psychiatric disease in any human societies irrespective of nation, culture, religion, economics or politics. Anxiety expression mediated by the amygdala may be suppressed by signals transmitted from the prefrontal cortex and hippocampus. KF-1 is an endoplasmic reticulum (ER)-based E3-ubiquitin (Ub) ligase with a RING-H2 finger motif at the C-terminus. The kf-1 gene expression is up-regulated in the frontal cortex and hippocampus in rats after anti-depressant treatments. The kf-1 null mice show no apparent abnormalities, but exhibit selectively pronounced anxiety-like behaviors or increased timidity-like responses. The kf-1 orthologous genes had been generated after the Poriferan emergence, and are found widely in all animals except insects, arachnids and threadworms such as Drosophila, Ixodes and Caenorhabditis, respectively. This suggests that the kf-1 gene may be relevant to some biological functions characteristic to animals. Based on these observations, the Anxiety Suppressor Model has been proposed, which assumes that KF-1 Ub ligase may suppress the amygdala-mediated anxiety by degrading some anxiety promoting protein(s), such as a neurotransmitter receptor, through the ER-associated degradation pathway in the frontal cortex and hippocampus. According to this model, the emotional sensitivity to environmental stresses may be regulated by the cellular protein level of KF-1 relative to that of the putative anxiety promoter. The kf-1 null mice should be useful in elucidating the molecular mechanisms of the anxiety regulation and for screening novel anxiolytic compounds, which may block the putative anxiety promoter.

  1. RET is a potential tumor suppressor gene in colorectal cancer

    Science.gov (United States)

    Luo, Yanxin; Tsuchiya, Karen D.; Park, Dong Il; Fausel, Rebecca; Kanngurn, Samornmas; Welcsh, Piri; Dzieciatkowski, Slavomir; Wang, Jianping; Grady, William M.

    2012-01-01

    Cancer arises as the consequence of mutations and epigenetic alterations that activate oncogenes and inactivate tumor suppressor genes. Through a genome-wide screen for methylated genes in colon neoplasms, we identified aberrantly methylated RET in colorectal cancer. RET, a transmembrane receptor tyrosine kinase and a receptor for the GDNF-family ligands, was one of the first oncogenes to be identified and has been shown to be an oncogene in thyroid cancer and pheochromocytoma. However, unexpectedly, we found RET is methylated in 27% of colon adenomas and in 63% of colorectal cancers, and now provide evidence that RET has tumor suppressor activity in colon cancer. The aberrant methylation of RET correlates with decreased RET expression, whereas the restoration of RET in colorectal cancer cell lines results in apoptosis. Furthermore, in support of a tumor suppressor function of RET, mutant RET has also been found in primary colorectal cancer. We now show that these mutations inactivate RET, which is consistent with RET being a tumor suppressor gene in the colon. These findings suggest that the aberrant methylation of RET and the mutational inactivation of RET promote colorectal cancer formation and that RET can serve as a tumor suppressor gene in the colon. Moreover, the increased frequency of methylated RET in colon cancers compared to adenomas suggests RET inactivation is involved in the progression of colon adenomas to cancer. PMID:22751117

  2. Structure of the Wilms Tumor Suppressor

    Energy Technology Data Exchange (ETDEWEB)

    Stoll, R.; Lee, B.M.; Debler, E.W.; Laity, J.H.; Wilson, I.A.; Dyson, H.J.; Wright, P.E.

    2009-06-04

    The zinc finger domain of the Wilms tumor suppressor protein (WT1) contains four canonical Cys{sub 2}His{sub 2} zinc fingers. WT1 binds preferentially to DNA sequences that are closely related to the EGR-1 consensus site. We report the structure determination by both X-ray crystallography and NMR spectroscopy of the WT1 zinc finger domain in complex with DNA. The X-ray structure was determined for the complex with a cognate 14 base-pair oligonucleotide, and composite X-ray/NMR structures were determined for complexes with both the 14 base-pair and an extended 17 base-pair DNA. This combined approach allowed unambiguous determination of the position of the first zinc finger, which is influenced by lattice contacts in the crystal structure. The crystal structure shows the second, third and fourth zinc finger domains inserted deep into the major groove of the DNA where they make base-specific interactions. The DNA duplex is distorted in the vicinity of the first zinc finger, with a cytidine twisted and tilted out of the base stack to pack against finger 1 and the tip of finger 2. By contrast, the composite X-ray/NMR structures show that finger 1 continues to follow the major groove in the solution complexes. However, the orientation of the helix is non-canonical, and the fingertip and the N terminus of the helix project out of the major groove; as a consequence, the zinc finger side-chains that are commonly involved in base recognition make no contact with the DNA. We conclude that finger 1 helps to anchor WT1 to the DNA by amplifying the binding affinity although it does not contribute significantly to binding specificity. The structures provide molecular level insights into the potential consequences of mutations in zinc fingers 2 and 3 that are associated with Denys-Drash syndrome and nephritic syndrome. The mutations are of two types, and either destabilize the zinc finger structure or replace key base contact residues.

  3. Efficient generation of P53 biallelic knockout Diannan miniature pigs via TALENs and somatic cell nuclear transfer

    Directory of Open Access Journals (Sweden)

    Youfeng Shen

    2017-11-01

    Full Text Available Abstract Background Pigs have many features that make them attractive as biomedical models for various diseases, including cancer. P53 is an important tumor suppressor gene that exerts a central role in protecting cells from oncogenic transformation and is mutated in a large number of human cancers. P53 mutations occur in almost every type of tumor and in over 50% of all tumors. In a recent publication, pigs with a mutated P53 gene were generated that resulted in lymphoma and renal and osteogenic tumors. However, approximately 80% of human tumors have dysfunctional P53. A P53-deficient pig model is still required to elucidate. Methods Transcription activator-like effector nucleases (TALENs were designed to target porcine P53 exon 4. The targeting activity was evaluated using a luciferase SSA recombination assay. P53 biallelic knockout (KO cell lines were established from single-cell colonies of fetal fibroblasts derived from Diannan miniature pigs followed by electroporation with TALENs plasmids. One cell line was selected as the donor cell line for somatic cell nuclear transfer (SCNT for the generation of P53 KO pigs. P53 KO stillborn fetuses and living piglets were obtained. Gene typing of the collected cloned individuals was performed by T7EI assay and sequencing. Fibroblast cells from Diannan miniature piglets with a P53 biallelic knockout or wild type were analyzed for the P53 response to doxorubicin treatment by confocal microscopy and western blotting. Results The luciferase SSA recombination assay revealed that the targeting activities of the designed TALENs were 55.35-fold higher than those of the control. Eight cell lines (8/19 were mutated for P53, and five of them were biallelic knockouts. One of the biallelic knockout cell lines was selected as nuclear donor cells for SCNT. The cloned embryos were transferred into five recipient gilts, three of them becoming pregnant. Five live fetuses were obtained from one surrogate by caesarean

  4. Firearm suppressor having enhanced thermal management for rapid heat dissipation

    Science.gov (United States)

    Moss, William C.; Anderson, Andrew T.

    2014-08-19

    A suppressor is disclosed for use with a weapon having a barrel through which a bullet is fired. The suppressor has an inner portion having a bore extending coaxially therethrough. The inner portion is adapted to be secured to a distal end of the barrel. A plurality of axial flow segments project radially from the inner portion and form axial flow paths through which expanding propellant gasses discharged from the barrel flow through. The axial flow segments have radially extending wall portions that define sections which may be filled with thermally conductive material, which in one example is a thermally conductive foam. The conductive foam helps to dissipate heat deposited within the suppressor during firing of the weapon.

  5. High-throughput knockout screen in fission yeast.

    Science.gov (United States)

    Gregan, Juraj; Rabitsch, Peter K; Rumpf, Cornelia; Novatchkova, Maria; Schleiffer, Alexander; Nasmyth, Kim

    2006-01-01

    We have designed the most efficient strategy to knock out genes in fission yeast Schizosaccharomyces pombe on a large scale. Our technique is based on knockout constructs that contain regions homologous to the target gene cloned into vectors carrying dominant drug-resistance markers. Most of the steps are carried out in a 96-well format, allowing simultaneous deletion of 96 genes in one batch. Based on our knockout technique, we designed a strategy for cloning knockout constructs for all predicted fission yeast genes, which is available in a form of a searchable database http://mendel.imp.ac.at/Pombe_deletion/. We validated this technique in a screen where we identified novel genes required for chromosome segregation during meiosis. Here, we present our protocol with detailed instructions. Using this protocol, one person can knock out 96 S. pombe genes in 8 days.

  6. Suppressor cell function is preserved in pemphigus and pemphigoid

    Energy Technology Data Exchange (ETDEWEB)

    King, A.J.; Schwartz, S.A.; Lopatin, D.; Voorhees, J.J.; Diaz, L.A.

    1982-09-01

    Human peripheral blood lymphocytes (PBL) are activated to become suppressor T cells (S-T-C) by incubation with Concanavalin-A (Con-A). This has become the standard method for evaluation of suppressor function in patients. S-T-C function has been found to be impaired in several autoimmune diseases, including systemic lupus erythematosus (SLE). Using this assay, we have investigated suppressor-cell function in 2 autoimmune disorders, bullous pemphigoid (BP) and pemphigus vulgaris (PV), studying 6 patients from each group. Three patients with active SLE (positive controls), and 11 normal donors (negative controls) were also included. None of these patients had received systemic therapy with the exception of 2 patients with PV who were treated with gold in the past. PBL from these patients were incubated with and without 40 micrograms/ml Con-A for 72 hr to generate suppressor cells. Both groups of PBL were then irradiated wih 1500 r cobalt. Co-cultures were set up in sextuplicate using normal PBL as responders. Responder PBL were stimulated with 0.5, 1.0, and 2.0 micrograms/ml of phytohemagglutin (PHA) and 5.0, 10.0, and 20.0 micrograms/ml of Con-A. Cultures were pulsed on day 3 with /sup 3/H-thymidine and harvested on day 4. Data were analyzed using Student's t-test. S-T-C function was found to be significantly impaired in SLE vs normal (p . 0.0316). No statistically significant difference was seen in BP (p . 0.5883) and PV (p . 0.0921) as compared with normals. A defect in suppressor cell function may still be present in patients with PV and BP for the defect may be antigen-specific and therefore remain undetected by the Con-A suppressor assay.

  7. Suppressor cell function is preserved in pemphigus and pemphigoid

    International Nuclear Information System (INIS)

    King, A.J.; Schwartz, S.A.; Lopatin, D.; Voorhees, J.J.; Diaz, L.A.

    1982-01-01

    Human peripheral blood lymphocytes (PBL) are activated to become suppressor T cells (S-T-C) by incubation with Concanavalin-A (Con-A). This has become the standard method for evaluation of suppressor function in patients. S-T-C function has been found to be impaired in several autoimmune diseases, including systemic lupus erythematosus (SLE). Using this assay, we have investigated suppressor-cell function in 2 autoimmune disorders, bullous pemphigoid (BP) and pemphigus vulgaris (PV), studying 6 patients from each group. Three patients with active SLE (positive controls), and 11 normal donors (negative controls) were also included. None of these patients had received systemic therapy with the exception of 2 patients with PV who were treated with gold in the past. PBL from these patients were incubated with and without 40 micrograms/ml Con-A for 72 hr to generate suppressor cells. Both groups of PBL were then irradiated wih 1500 r cobalt. Co-cultures were set up in sextuplicate using normal PBL as responders. Responder PBL were stimulated with 0.5, 1.0, and 2.0 micrograms/ml of phytohemagglutin (PHA) and 5.0, 10.0, and 20.0 micrograms/ml of Con-A. Cultures were pulsed on day 3 with 3 H-thymidine and harvested on day 4. Data were analyzed using Student's t-test. S-T-C function was found to be significantly impaired in SLE vs normal (p . 0.0316). No statistically significant difference was seen in BP (p . 0.5883) and PV (p . 0.0921) as compared with normals. A defect in suppressor cell function may still be present in patients with PV and BP for the defect may be antigen-specific and therefore remain undetected by the Con-A suppressor assay

  8. Tumour suppressor genes in sporadic epithelial ovarian cancer

    DEFF Research Database (Denmark)

    Liu, Ying; Ganesan, Trivadi S

    2002-01-01

    Ovarian cancer is the most frequent cause of death from gynaecological malignancies in the western world, and sporadic epithelial ovarian cancer is its most predominant form. The aetiology of sporadic ovarian cancer remains unknown. Genetic studies have enabled a better understanding...... of the evolution of tumour progression. A major focus of research has been to identify tumour suppressor genes implicated in sporadic ovarian cancer over the past decade. Several tumour suppressor genes have been identified by strategies such as positional cloning and differential expression display. Further...... research is warranted to understand fully their contribution to the pathogenesis of sporadic ovarian cancer....

  9. Suppressors of RNA silencing encoded by tomato leaf curl

    Indian Academy of Sciences (India)

    Whitefly-transmitted begomoviruses infecting tomato crop code for five different proteins, ORF AC4, ORF AC2 and ORF AV2 in DNA-A component, ORF BV1 in DNA-B ... In the present study suppressor function of ORF C1 of three betasatellites Tomato leaf curl Bangalore betasatellite ToLCBB-[IN:Hess:08], Cotton leaf curl ...

  10. Identification of a maize chlorotic dwarf virus silencing suppressor protein.

    Science.gov (United States)

    Stewart, Lucy R; Jarugula, Sridhar; Zhao, Yujing; Qu, Feng; Marty, DeeMarie

    2017-04-01

    Maize chlorotic dwarf virus (MCDV), a member of the genus Waikavirus, family Secoviridae, has a 11784 nt (+)ssRNA genome that encodes a 389kDa proteolytically processed polyprotein. We show that the N-terminal 78kDa polyprotein (R78) of MCDV acts as a suppressor of RNA silencing in a well-established assay system. We further demonstrate that R78 is cleaved by the viral 3C-like protease into 51 and 27kDa proteins (p51 and p27), and that p51 is responsible for silencing suppressor activity. Silencing suppressor activity of R78 is conserved in three divergent MCDV strains (MCDV-Severe, MCDV-M1, and MCDV-Tennessee), as well as the waikavirus Bellflower vein chlorosis virus, but was not detected for orthologous protein of Rice tungro spherical virus (RTSV-A) or the similarly-positioned protein from the sequivirus Parsnip yellow fleck virus (PYFV). This is the first identification of a virus suppressor of RNA silencing encoded by a waikavirus. Copyright © 2017. Published by Elsevier Inc.

  11. Intellectual disability, oncogenes and tumour suppressor genes: the ...

    Indian Academy of Sciences (India)

    associated with Van-Hippel Lindau syndrome, an inherited neoplastic disorder with retinal and central nervous haeman- gioblastomas and high risk of renal cancers (Maher et al. Keywords. array-CGH; mental retardation; oncogenes; tumour suppressor genes; intellectual disability. Journal of Genetics, Vol. 91, No.

  12. Suppressors of DnaAATP imposed overinitiation in Escherichia coli

    DEFF Research Database (Denmark)

    Charbon, Godefroid; Riber, Leise; Cohen, Malene

    2011-01-01

    Chromosome replication in Escherichia coli is limited by the supply of DnaA associated with ATP. Cells deficient in RIDA (Regulatory Inactivation of DnaA) due to a deletion of the hda gene accumulate suppressor mutations (hsm) to counteract the overinitiation caused by an elevated DnaAATP level...

  13. Identification of a maize chlorotic dwarf virus silencing suppressor protein

    Science.gov (United States)

    Maize chlorotic dwarf virus (MCDV), a member of the genus Waikavirus, family Secoviridae, has a 11784 nt (+)ssRNA genome that encodes a 389 kDa proteolytically processed polyprotein. We show that an N-terminal 78kDa polyprotein (R78) has silencing suppressor activity, that it is cleaved by the viral...

  14. Intellectual disability, oncogenes and tumour suppressor genes: the ...

    Indian Academy of Sciences (India)

    disability, the presence of CNV including gene expressed in the brain or with specific brain function is a strong argument. In contrast, CNV affecting only genes involved in oncogen- esis are mostly ignored. However, links between some onco- genes or tumour suppressor genes and intellectual disability deserve attention.

  15. Suppressors of RNA silencing encoded by tomato leaf curl ...

    Indian Academy of Sciences (India)

    In the present study suppressor function of ORF C1 of three betasatellites Tomato leaf curl Bangalore betasatellite ToLCBB-[IN:Hess:08], Cotton leaf curl Multan betasatellite CLCuMB–[IN:Sri:02] and Luffa leaf distortion betasatellite LuLDB-[IN:Lu:04] were examined. Agroinfiltration of GFP-silenced Nicotiana tabaccum cv.

  16. Intellectual disability, oncogenes and tumour suppressor genes: the ...

    Indian Academy of Sciences (India)

    Keywords. array-CGH; mental retardation; oncogenes; tumour suppressor genes; intellectual disability. Author Affiliations. M. Bidart1 2 3 C. Coutton4 5 3. Plateforme Protéomique et Transcriptomique Clinique, Pole Recherche, CHU Grenoble, 38043 Grenoble, France; Equipe, Nanomédecine et Cerveau, Inserm U836, ...

  17. Hepatic changes in metabolic gene expression in old ghrelin and ghrelin receptor knockout mice

    Science.gov (United States)

    Ghrelin knockout (GKO) and ghrelin receptor (growth hormone secretagogue receptor) knockout (GHSRKO) mice exhibit enhanced insulin sensitivity, but the mechanism is unclear. Insulin sensitivity declines with age and is inversely associated with accumulation of lipid in liver, a key glucoregulatory ...

  18. An inducible knockout mouse to model the cell-autonomous role of PTEN in initiating endometrial, prostate and thyroid neoplasias.

    Science.gov (United States)

    Mirantes, Cristina; Eritja, Núria; Dosil, Maria Alba; Santacana, Maria; Pallares, Judit; Gatius, Sónia; Bergadà, Laura; Maiques, Oscar; Matias-Guiu, Xavier; Dolcet, Xavier

    2013-05-01

    PTEN is one of the most frequently mutated tumor suppressor genes in human cancers. The role of PTEN in carcinogenesis has been validated by knockout mouse models. PTEN heterozygous mice develop neoplasms in multiple organs. Unfortunately, the embryonic lethality of biallelic excision of PTEN has inhibited the study of complete PTEN deletion in the development and progression of cancer. By crossing PTEN conditional knockout mice with transgenic mice expressing a tamoxifen-inducible Cre-ER(T) under the control of a chicken actin promoter, we have generated a tamoxifen-inducible mouse model that allows temporal control of PTEN deletion. Interestingly, administration of a single dose of tamoxifen resulted in PTEN deletion mainly in epithelial cells, but not in stromal, mesenchymal or hematopoietic cells. Using the mT/mG double-fluorescent Cre reporter mice, we demonstrate that epithelial-specific PTEN excision was caused by differential Cre activity among tissues and cells types. Tamoxifen-induced deletion of PTEN resulted in extremely rapid and consistent formation of endometrial in situ adenocarcinoma, prostate intraepithelial neoplasia and thyroid hyperplasia. We also analyzed the role of PTEN ablation in other epithelial cells, such as the tubular cells of the kidney, hepatocytes, colonic epithelial cells or bronchiolar epithelium, but those tissues did not exhibit neoplastic growth. Finally, to validate this model as a tool to assay the efficacy of anti-tumor drugs in PTEN deficiency, we administered the mTOR inhibitor everolimus to mice with induced PTEN deletion. Everolimus dramatically reduced the progression of endometrial proliferations and significantly reduced thyroid hyperplasia. This model could be a valuable tool to study the cell-autonomous mechanisms involved in PTEN-loss-induced carcinogenesis and provides a good platform to study the effect of anti-neoplastic drugs on PTEN-negative tumors.

  19. Akt2/LDLr double knockout mice display impaired glucose tolerance and develop more complex atherosclerotic plaques than LDLr knockout mice

    NARCIS (Netherlands)

    Rensing, Katrijn L.; de Jager, Saskia C. A.; Stroes, Erik S.; Vos, Mariska; Twickler, Marcel Th B.; Dallinga-Thie, Geesje M.; de Vries, Carlie J. M.; Kuiper, Johan; Bot, Ilze; von der Thüsen, Jan H.

    2014-01-01

    To characterize the phenotype of Akt2/low-density-lipoprotein receptor double knockout (dKO) (Akt2/LDLr dKO) mice with respect to insulin resistance and features of atherosclerotic plaque progression. Metabolic profile and atherosclerotic plaque progression were compared between LDLr KO mice and

  20. Brush border Myosin Ia has tumor suppressor activity in the intestine

    Science.gov (United States)

    Mazzolini, Rocco; Dopeso, Higinio; Mateo-Lozano, Silvia; Chang, Wakam; Rodrigues, Paulo; Bazzocco, Sarah; Alazzouzi, Hafid; Landolfi, Stefania; Hernández-Losa, Javier; Andretta, Elena; Alhopuro, Pia; Espín, Eloy; Armengol, Manel; Tabernero, Josep; Ramón y Cajal, Santiago; Kloor, Matthias; Gebert, Johannes; Mariadason, John M.; Schwartz, Simo; Aaltonen, Lauri A.; Mooseker, Mark S.; Arango, Diego

    2012-01-01

    The loss of the epithelial architecture and cell polarity/differentiation is known to be important during the tumorigenic process. Here we demonstrate that the brush border protein Myosin Ia (MYO1A) is important for polarization and differentiation of colon cancer cells and is frequently inactivated in colorectal tumors by genetic and epigenetic mechanisms. MYO1A frame-shift mutations were observed in 32% (37 of 116) of the colorectal tumors with microsatellite instability analyzed, and evidence of promoter methylation was observed in a significant proportion of colon cancer cell lines and primary colorectal tumors. The loss of polarization/differentiation resulting from MYO1A inactivation is associated with higher tumor growth in soft agar and in a xenograft model. In addition, the progression of genetically and carcinogen-initiated intestinal tumors was significantly accelerated in Myo1a knockout mice compared with Myo1a wild-type animals. Moreover, MYO1A tumor expression was found to be an independent prognostic factor for colorectal cancer patients. Patients with low MYO1A tumor protein levels had significantly shorter disease-free and overall survival compared with patients with high tumoral MYO1A (logrank test P = 0.004 and P = 0.009, respectively). The median time-to-disease recurrence in patients with low MYO1A was 1 y, compared with >9 y in the group of patients with high MYO1A. These results identify MYO1A as a unique tumor-suppressor gene in colorectal cancer and demonstrate that the loss of structural brush border proteins involved in cell polarity are important for tumor development. PMID:22307608

  1. Critical tumor suppressor function mediated by epithelial Mig-6 in endometrial cancer

    Science.gov (United States)

    Kim, Tae Hoon; Lee, Dong-Kee; Cho, Sung-Nam; Orvis, Grant D.; Behringer, Richard R.; Lydon, John P.; Ku, Bon Jeong; McCampbell, Adrienne S.; Broaddus, Russell R.; Jeong, Jae-Wook

    2013-01-01

    Endometrial cancer is preceded by endometrial hyperplasia, unopposed estrogen exposure and genetic alterations, but the precise causes of endometrial cancer remain uncertain. Mig-6, mainly known as a negative regulator of the EGF receptor, is an important mediator of progesterone signaling in the uterus, where it mediates tumor suppression by modulating endometrial stromal-epithelial communications. In this study, we investigated the function of Mig-6 in the uterine epithelium using a tissue-specific gene knockout strategy, in which floxed Mig-6 (Mig-6f/f) mice were crossed to Wnt7a-Cre mice (Wnt7acre+ Mig-6f/f). Wnt7acre+ Mig-6f/f mice developed endometrial hyperplasia and estrogen-dependent endometrial cancer, exhibiting increased proliferation in epithelial cells as well as apoptosis in sub-epithelial stromal cells. We documented increased expression of NOTCH1 and BIRC3 in epithelial cells of Wnt7acre+ Mig-6f/f mice and decreased expression of the progesterone receptor (PR) in stromal cells. Progesterone therapy controls endometrial growth and prevents endometrial cancer, but the effectiveness of progesterone as a treatment for women with endometrial cancer is less clear. We noted that the hyperplasic phenotype of Wnt7acre+ Mig-6f/f mice was prevented by progesterone treatment, whereas this treatment had no effect in PRcre/+ Mig-6f/f mice where Mig-6 was deleted in both the epithelial and stromal compartments of the uterus. In contrast, activation of progesterone signaling in the stroma regulated proliferation and apoptosis in the epithelium via suppression of ERα signaling there. In summary, our results establish that epithelial Mig-6 functions as a critical tumor suppressor that mediates the ability of progesterone to prevent the development of endometrial cancer. PMID:23811943

  2. Pam2 lipopeptides systemically increase myeloid-derived suppressor cells through TLR2 signaling

    Energy Technology Data Exchange (ETDEWEB)

    Maruyama, Akira; Shime, Hiroaki, E-mail: shime@med.hokudai.ac.jp; Takeda, Yohei; Azuma, Masahiro; Matsumoto, Misako; Seya, Tsukasa, E-mail: seya-tu@pop.med.hokudai.ac.jp

    2015-02-13

    Myeloid-derived suppressor cells (MDSCs) are immature myeloid cells that exhibit potent immunosuppressive activity. They are increased in tumor-bearing hosts and contribute to tumor development. Toll-like receptors (TLRs) on MDSCs may modulate the tumor-supporting properties of MDSCs through pattern-recognition. Pam2 lipopeptides represented by Pam2CSK4 serve as a TLR2 agonist to exert anti-tumor function by dendritic cell (DC)-priming that leads to NK cell activation and cytotoxic T cell proliferation. On the other hand, TLR2 enhances tumor cell progression/invasion by activating tumor-infiltrating macrophages. How MDSCs respond to TLR2 agonists has not yet been determined. In this study, we found intravenous administration of Pam2CSK4 systemically up-regulated the frequency of MDSCs in EG7 tumor-bearing mice. The frequency of tumor-infiltrating MDSCs was accordingly increased in response to Pam2CSK4. MDSCs were not increased by Pam2CSK4 stimuli in TLR2 knockout (KO) mice. Adoptive transfer experiments using CFSE-labeled MDSCs revealed that the TLR2-positive MDSCs survived long in tumor-bearing mice in response to Pam2CSK4 treatment. Since the increased MDSC population sustained immune-suppressive properties, our study suggests that Pam2CSK4-triggered TLR2 activation enhances the MDSC potential and suppress antitumor immune response in tumor microenvironment. - Highlights: • Pam2CSK4 administration induces systemic accumulation of CD11b{sup +}Gr1{sup +} MDSCs. • TLR2 is essential for Pam2CSK4-induced accumulation of CD11b{sup +}Gr1{sup +} MDSCs. • Pam2CSK4 supports survival of CD11b{sup +}Gr1{sup +} MDSCs in vivo.

  3. Vibration behavior of fuel-element vibration suppressors for the advanced power reactor

    Science.gov (United States)

    Adams, D. W.; Fiero, I. B.

    1973-01-01

    Preliminary shock and vibration tests were performed on vibration suppressors for the advanced power reactor for space application. These suppressors position the fuel pellets in a pin type fuel element. The test determined the effect of varying axial clearance on the behavior of the suppressors when subjected to shock and vibratory loading. The full-size suppressor was tested in a mockup model of fuel and clad which required scaling of test conditions. The test data were correlated with theoretical predictions for suppressor failure. Good agreement was obtained. The maximum difference with damping neglected was about 30 percent. Neglecting damping would result in a conservative design.

  4. Loss of RhoB expression enhances the myelodysplastic phenotype of mammalian diaphanous-related Formin mDia1 knockout mice.

    Directory of Open Access Journals (Sweden)

    Aaron D DeWard

    Full Text Available Myelodysplastic syndrome (MDS is characterized by ineffective hematopoiesis and hyperplastic bone marrow. Complete loss or interstitial deletions of the long arm of chromosome 5 occur frequently in MDS. One candidate tumor suppressor on 5q is the mammalian Diaphanous (mDia-related formin mDia1, encoded by DIAPH1 (5q31.3. mDia-family formins act as effectors for Rho-family small GTP-binding proteins including RhoB, which has also been shown to possess tumor suppressor activity. Mice lacking the Drf1 gene that encodes mDia1 develop age-dependent myelodysplastic features. We crossed mDia1 and RhoB knockout mice to test whether the additional loss of RhoB expression would compound the myelodysplastic phenotype. Drf1(-/-RhoB(-/- mice are fertile and develop normally. Relative to age-matched Drf1(-/-RhoB(+/- mice, the age of myelodysplasia onset was earlier in Drf1(-/-RhoB(-/- animals--including abnormally shaped erythrocytes, splenomegaly, and extramedullary hematopoiesis. In addition, we observed a statistically significant increase in the number of activated monocytes/macrophages in both the spleen and bone marrow of Drf1(-/-RhoB(-/- mice relative to Drf1(-/-RhoB(+/- mice. These data suggest a role for RhoB-regulated mDia1 in the regulation of hematopoietic progenitor cells.

  5. Human Genetic Disorders and Knockout Mice Deficient in Glycosaminoglycan

    Directory of Open Access Journals (Sweden)

    Shuji Mizumoto

    2014-01-01

    Full Text Available Glycosaminoglycans (GAGs are constructed through the stepwise addition of respective monosaccharides by various glycosyltransferases and maturated by epimerases and sulfotransferases. The structural diversity of GAG polysaccharides, including their sulfation patterns and sequential arrangements, is essential for a wide range of biological activities such as cell signaling, cell proliferation, tissue morphogenesis, and interactions with various growth factors. Studies using knockout mice of enzymes responsible for the biosynthesis of the GAG side chains of proteoglycans have revealed their physiological functions. Furthermore, mutations in the human genes encoding glycosyltransferases, sulfotransferases, and related enzymes responsible for the biosynthesis of GAGs cause a number of genetic disorders including chondrodysplasia, spondyloepiphyseal dysplasia, and Ehlers-Danlos syndromes. This review focused on the increasing number of glycobiological studies on knockout mice and genetic diseases caused by disturbances in the biosynthetic enzymes for GAGs.

  6. Rapid curation of gene disruption collections using Knockout Sudoku.

    Science.gov (United States)

    Anzai, Isao A; Shaket, Lev; Adesina, Oluwakemi; Baym, Michael; Barstow, Buz

    2017-10-01

    Knockout Sudoku is a method for the construction of whole-genome knockout collections for a wide range of microorganisms with as little as 3 weeks of dedicated labor and at a cost of ∼$10,000 for a collection for a single organism. The method uses manual 4D combinatorial pooling, next-generation sequencing, and a Bayesian inference algorithm to rapidly process and then accurately annotate the extremely large progenitor transposon insertion mutant collections needed to achieve saturating coverage of complex microbial genomes. This method is ∼100× faster and 30× lower in cost than the next comparable method (In-seq) for annotating transposon mutant collections by combinatorial pooling and next-generation sequencing. This method facilitates the rapid, algorithmically guided condensation and curation of the progenitor collection into a high-quality, nonredundant collection that is suitable for rapid genetic screening and gene discovery.

  7. Pauli blocking and medium effects in nucleon knockout reactions

    International Nuclear Information System (INIS)

    Bertulani, C. A.; De Conti, C.

    2010-01-01

    We study medium modifications of the nucleon-nucleon (NN) cross sections and their influence on the nucleon knockout reactions. Using the eikonal approximation, we compare the results obtained with free NN cross sections with those obtained with a purely geometrical treatment of Pauli blocking and with NN obtained with more elaborated Dirac-Bruecker methods. The medium effects are parametrized in terms of the baryon density. We focus on symmetric nuclear matter, although the geometrical Pauli blocking also allows for the treatment of asymmetric nuclear matter. It is shown that medium effects can change the nucleon knockout cross sections and momentum distributions up to 10% in the energy range E lab =50-300 MeV/nucleon. The effect is more evident in reactions involving halo nuclei.

  8. Physiological roles of CNS muscarinic receptors gained from knockout mice

    DEFF Research Database (Denmark)

    Thomsen, Morgane; Sørensen, Gunnar; Dencker, Ditte

    2017-01-01

    , knockout mice are likely to continue to provide valuable insights into brain physiology and pathophysiology, and advance the development of new medications for a range of conditions such as Alzheimer's disease, Parkinson's disease, schizophrenia, and addictions, as well as non-opioid analgesics...... receptors modulating neuronal activity and neurotransmitter release in many brain regions, shaping neuronal plasticity, and affecting functions ranging from motor and sensory function to cognitive processes. As gene targeting technology evolves including the use of conditional, cell type specific strains...

  9. One-neutron knockout from 51-55Sc

    International Nuclear Information System (INIS)

    Schwertel, S.; Maierbeck, P.; Gernhaeuser, R.; Bildstein, V.; Boehmer, M.; Eppinger, K.; Faestermann, T.; Friese, J.; Fabbietti, L.; Maier, L.; Winkler, S.; Kruecken, R.; Kroell, T.; Alvarez-Pol, H.; Benjamim, E.A.; Benlliure, J.; Caamano, M.; Cortina-Gil, D.; Gascon, M.; Kurtukian, T.; Perez, D.; Rodriguez-Tajes, C.; Aksouh, F.; Aumann, T.; Behr, K.; Boretzky, K.; Bruenle, A.; Chatillon, A.; Chulkov, L.V.; Geissel, H.; Gerl, J.; Gorska, M.; Kojouharov, I.; Klimkiewicz, A.; Kurz, N.; Nociforo, C.; Schaffner, H.; Simon, H.; Stanoiu, M.; Suemmerer, K.; Weick, H.; Borge, M.J.G.; Pascual-Izarra, C.; Perea, A.; Tengblad, O.; Buerger, A.; Casarejos, E.; Brown, B.A.; Enders, J.; Schrieder, G.; Hansen, P.G.; Jonson, B.; Nyman, G.; Kanungo, R.; Kiselev, O.; Larsson, K.; Le Bleis, T.; Mahata, K.; Nilsson, T.; Prochazka, A.; Rossi, D.; Sitar, B.; Otsuka, T.; Tostevin, J.A.; Rae, W.D.M.

    2012-01-01

    Results are presented from a one-neutron knockout experiment at relativistic energies of ∼ 420 A MeV on 51-55 Sc using the GSI Fragment Separator as a two-stage magnetic spectrometer and the MINIBALL array for gamma-ray detection. Inclusive longitudinal momentum distributions and cross-sections were measured enabling the determination of the contributions corresponding to knockout from the νp 1/2 , νp 3/2 , (L = 1) and νf 7/2 , νf 5/2 (L = 3) neutron orbitals. The observed L = 1 and L = 3 contributions are compared with theoretical cross-sections using eikonal knockout theory and spectroscopic factors from shell model calculations using the GXPF1A interaction. The measured inclusive knockout cross-sections generally follow the trends expected theoretically and given by the spectroscopic strength predicted from the shell model calculations. However, the deduced L = 1 cross-sections are generally 30-40% higher while the L = 3 contributions are about a factor of two smaller than predicted. This points to a promotion of neutrons from the νf 7/2 to the νp 3/2 orbital indicating a weakening of the N = 28 shell gap in these nuclei. While this is not predicted for the phenomenological GXPF1A interaction such a weakening is predicted by recent calculations using realistic low-momentum interactions V low k obtained by evolving a chiral N3LO nucleon-nucleon potential. (orig.)

  10. Single proton knock-out from 24F

    International Nuclear Information System (INIS)

    Thoennessen, M.; Baumann, T.; Brown, B.A.; Enders, J.; Frank, N.H.; Hansen, P.G.; Heckman, P.; Luther, B.A.; Seitz, J.P.; Stolz, A.; Tryggestad, E.

    2004-01-01

    The measurement of the single proton knock-out reaction from 24 F on a 12 C target at 46.7 MeV/nucleon yielded a 23 O ground state population of (6.6+/-1.0) mb. The data were compared to calculations based on the many-body shell model and the eikonal theory. The results are consistent with a [0d5/26]-bar 1s1/2 configuration of 23 O

  11. Hypomethylation of tumor suppressor genes in odontogenic myxoma

    OpenAIRE

    Moreira,Paula Rocha; Cardoso,Fabiano Pereira; Brito,João Artur Ricieri; Batista,Aline Carvalho; Gomes,Carolina Cavaliéri; Gomez,Ricardo Santiago

    2011-01-01

    Odontogenic myxoma (OM) is an ectomesenchymal benign odontogenic tumor characterized by spindle or stellate-shaped cells embedded in an abundant myxoid or mucoid extracellular matrix. DNA methylation is characterized by the addition of methyl groups in cytosines within CpG islands in the promoter gene. DNA methylation can decrease the expression of tumor suppressor genes and contribute to the development of neoplastic lesions. The aim of study was to evaluate the methylation pattern of the tu...

  12. Molecular biology III - Oncogenes and tumor suppressor genes

    International Nuclear Information System (INIS)

    Giaccia, Amato J.

    1996-01-01

    Purpose: The purpose of this course is to introduce to radiation oncologists the basic concepts of tumorigenesis, building on the information that will be presented in the first and second part of this series of lectures. Objective: Our objective is to increase the current understanding of radiation oncologists with the process of tumorigenesis, especially focusing on genes that are altered in many tumor types that are potential candidates for novel molecular strategies. As strategies to treat cancer of cancer are becoming more sophisticated, it will be important for both the practitioner and academician to develop a basic understanding of the function of cancer 'genes'. This will be the third in a series of refresher courses that are meant to address recent advances in Cancer Biology in a way that both clinicians without previous knowledge of molecular biology or experienced researchers will find interesting. The lecture will begin with a basic overview of tumorigenesis; methods of detecting chromosome/DNA alterations, approaches used to isolate oncogenes and tumor suppressor genes, and their role in cell killing by apoptosis. Special attention will be given to oncogenes and tumor suppressor genes that are modulated by ionizing radiation and the tumor microenvironment. We will relate the biology of oncogenes and tumor suppressor genes to basic aspects of radiation biology that would be important in clinical practice. Finally, we will review recent studies on the prognostic significance of p53 mutations and apoptosis in tumor specimens. The main point of this lecture is to relate both researcher and clinician what are the therapeutic ramifications of oncogene and tumor suppressor gene mutations found in human neoptasia

  13. FOXP3 as X-linked Tumor Suppressor

    OpenAIRE

    Wang, Lizhong; Liu, Runhua; Ribick, Mark; Zheng, Pan; Liu, Yang

    2010-01-01

    The FOXP3 gene was initially identified because its mutation caused lethal autoimmune diseases in mouse and human. Mice with heterozygous mutation of Foxp3 succumb to mammary tumor spontaneously, while those with prostate-specific deletion develop prostate intraepithelial neoplasia. Somatic mutations, deletion and epigenetic inactivation of FOXP3 are widespread among human breast and prostate cancers. Unlike autosomal tumor suppressor genes that were usually inactivated by mutations in both a...

  14. A muscle-specific knockout implicates nuclear receptor coactivator MED1 in the regulation of glucose and energy metabolism.

    Science.gov (United States)

    Chen, Wei; Zhang, Xiaoting; Birsoy, Kivanc; Roeder, Robert G

    2010-06-01

    As conventional transcriptional factors that are activated in diverse signaling pathways, nuclear receptors play important roles in many physiological processes that include energy homeostasis. The MED1 subunit of the Mediator coactivator complex plays a broad role in nuclear receptor-mediated transcription by anchoring the Mediator complex to diverse promoter-bound nuclear receptors. Given the significant role of skeletal muscle, in part through the action of nuclear receptors, in glucose and fatty acid metabolism, we generated skeletal muscle-specific Med1 knockout mice. Importantly, these mice show enhanced insulin sensitivity and improved glucose tolerance as well as resistance to high-fat diet-induced obesity. Furthermore, the white muscle of these mice exhibits increased mitochondrial density and expression of genes specific to type I and type IIA fibers, indicating a fast-to-slow fiber switch, as well as markedly increased expression of the brown adipose tissue-specific UCP-1 and Cidea genes that are involved in respiratory uncoupling. These dramatic results implicate MED1 as a powerful suppressor in skeletal muscle of genetic programs implicated in energy expenditure and raise the significant possibility of therapeutical approaches for metabolic syndromes and muscle diseases through modulation of MED1-nuclear receptor interactions.

  15. Classification of suppressor additives based on synergistic and antagonistic ensemble effects

    International Nuclear Information System (INIS)

    Broekmann, P.; Fluegel, A.; Emnet, C.; Arnold, M.; Roeger-Goepfert, C.; Wagner, A.; Hai, N.T.M.; Mayer, D.

    2011-01-01

    Highlights: → Three fundamental types of suppressor additives for copper electroplating could be identified by means of potential transient measurements. → These suppressor additives differ in their synergistic and antagonistic interplay with anions that are chemisorbed on the metallic copper surface during electrodeposition. → In addition these suppressor chemistries reveal different barrier properties with respect to cupric ions and plating additives (Cl, SPS). - Abstract: Three fundamental types of suppressor additives for copper electroplating could be identified by means of potential transient measurements. These suppressor additives differ in their synergistic and antagonistic interplay with anions that are chemisorbed on the metallic copper surface during electrodeposition. In addition these suppressor chemistries reveal different barrier properties with respect to cupric ions and plating additives (Cl, SPS). While the type-I suppressor selectively forms efficient barriers for copper inter-diffusion on chloride-terminated electrode surfaces we identified a type-II suppressor that interacts non-selectively with any kind of anions chemisorbed on copper (chloride, sulfate, sulfonate). Type-I suppressors are vital for the superconformal copper growth mode in Damascene processing and show an antagonistic interaction with SPS (Bis-Sodium-Sulfopropyl-Disulfide) which involves the deactivation of this suppressor chemistry. This suppressor deactivation is rationalized in terms of compositional changes in the layer of the chemisorbed anions due to the competition of chloride and MPS (Mercaptopropane Sulfonic Acid) for adsorption sites on the metallic copper surface. MPS is the product of the dissociative SPS adsorption within the preexisting chloride matrix on the copper surface. The non-selectivity in the adsorption behavior of the type-II suppressor is rationalized in terms of anion/cation pairing effects of the poly-cationic suppressor and the anion

  16. Cdh11 Acts as a Tumor Suppressor in a Murine Retinoblastoma Model by Facilitating Tumor Cell Death

    Science.gov (United States)

    Marchong, Mellone N.; Yurkowski, Christine; Ma, Clement; Spencer, Clarellen; Pajovic, Sanja; Gallie, Brenda L.

    2010-01-01

    CDH11 gene copy number and expression are frequently lost in human retinoblastomas and in retinoblastomas arising in TAg-RB mice. To determine the effect of Cdh11 loss in tumorigenesis, we crossed Cdh11 null mice with TAg-RB mice. Loss of Cdh11 had no gross morphological effect on the developing retina of Cdh11 knockout mice, but led to larger retinal volumes in mice crossed with TAg-RB mice (p = 0.01). Mice null for Cdh11 presented with fewer TAg-positive cells at postnatal day 8 (PND8) (p = 0.01) and had fewer multifocal tumors at PND28 (p = 0.016), compared to mice with normal Cdh11 alleles. However, tumor growth was faster in Cdh11-null mice between PND8 and PND84 (p = 0.003). In tumors of Cdh11-null mice, cell death was decreased 5- to 10-fold (p<0.03 for all markers), while proliferation in vivo remained unaffected (p = 0.121). Activated caspase-3 was significantly decreased and β-catenin expression increased in Cdh11 knockdown experiments in vitro. These data suggest that Cdh11 displays tumor suppressor properties in vivo and in vitro in murine retinoblastoma through promotion of cell death. PMID:20421947

  17. Cdh11 acts as a tumor suppressor in a murine retinoblastoma model by facilitating tumor cell death.

    Directory of Open Access Journals (Sweden)

    Mellone N Marchong

    2010-04-01

    Full Text Available CDH11 gene copy number and expression are frequently lost in human retinoblastomas and in retinoblastomas arising in TAg-RB mice. To determine the effect of Cdh11 loss in tumorigenesis, we crossed Cdh11 null mice with TAg-RB mice. Loss of Cdh11 had no gross morphological effect on the developing retina of Cdh11 knockout mice, but led to larger retinal volumes in mice crossed with TAg-RB mice (p = 0.01. Mice null for Cdh11 presented with fewer TAg-positive cells at postnatal day 8 (PND8 (p = 0.01 and had fewer multifocal tumors at PND28 (p = 0.016, compared to mice with normal Cdh11 alleles. However, tumor growth was faster in Cdh11-null mice between PND8 and PND84 (p = 0.003. In tumors of Cdh11-null mice, cell death was decreased 5- to 10-fold (p<0.03 for all markers, while proliferation in vivo remained unaffected (p = 0.121. Activated caspase-3 was significantly decreased and beta-catenin expression increased in Cdh11 knockdown experiments in vitro. These data suggest that Cdh11 displays tumor suppressor properties in vivo and in vitro in murine retinoblastoma through promotion of cell death.

  18. Modulation of allogeneic stimulation in man. I. Characterization of an in vitro induced suppressor macrophage population

    International Nuclear Information System (INIS)

    Stux, S.V.; Dubey, D.P.; Yunis, E.J.

    1981-01-01

    Cultured human peripheral blood mononuclear cells suppressed the allogeneic response of fresh autologous lymphocytes. This suppressor activity developed gradually over a period of one week. The cells primarily responsible for this effect were enriched by Ficoll density gradient centrifugation. It was found that the suppressor cell is a large, low density nylon wool adherent, radioresistant, phagocytic, and nonspecific esterase positive mononuclear cell. Moreover, these cells did not form E rosettes and were Fc positive. Electron microscopy confirmed that suppressor cells were macrophage like. Suppressor activity was not due to cytotoxicity, crowding, or steric hinderance by the cultured cells. The suppressor macrophage population did not appear to inhibit the allogeneic response via prostaglandin or arginase release, or interfere with the tritiated thymidine uptake by release of endogenous thymidine. The above system is viewed as an in vitro model of immune regulation by suppressor macrophages, in the context of allogeneic response

  19. Robust and sensitive analysis of mouse knockout phenotypes.

    Directory of Open Access Journals (Sweden)

    Natasha A Karp

    Full Text Available A significant challenge of in-vivo studies is the identification of phenotypes with a method that is robust and reliable. The challenge arises from practical issues that lead to experimental designs which are not ideal. Breeding issues, particularly in the presence of fertility or fecundity problems, frequently lead to data being collected in multiple batches. This problem is acute in high throughput phenotyping programs. In addition, in a high throughput environment operational issues lead to controls not being measured on the same day as knockouts. We highlight how application of traditional methods, such as a Student's t-Test or a 2-way ANOVA, in these situations give flawed results and should not be used. We explore the use of mixed models using worked examples from Sanger Mouse Genome Project focusing on Dual-Energy X-Ray Absorptiometry data for the analysis of mouse knockout data and compare to a reference range approach. We show that mixed model analysis is more sensitive and less prone to artefacts allowing the discovery of subtle quantitative phenotypes essential for correlating a gene's function to human disease. We demonstrate how a mixed model approach has the additional advantage of being able to include covariates, such as body weight, to separate effect of genotype from these covariates. This is a particular issue in knockout studies, where body weight is a common phenotype and will enhance the precision of assigning phenotypes and the subsequent selection of lines for secondary phenotyping. The use of mixed models with in-vivo studies has value not only in improving the quality and sensitivity of the data analysis but also ethically as a method suitable for small batches which reduces the breeding burden of a colony. This will reduce the use of animals, increase throughput, and decrease cost whilst improving the quality and depth of knowledge gained.

  20. Pre-Equilibrium Cluster Emission with Pickup and Knockout

    International Nuclear Information System (INIS)

    Betak, E.

    2005-01-01

    We present a generalization of the Iwamoto-Harada-Bisplinghoff pre-equilibrium model of light cluster formation and emission, which is enhanced by allowing for possible admixtures of knockout for strongly coupled ejectiles, like α's. The model is able to attain the Weisskopf-Ewing formula for compound-nucleus decay at long-time limit; it keeps the philosophy of pre-equilibrium decay during the equilibration stage and it describes the initial phase of a reaction as direct process(es) expressed using the language of the exciton model

  1. Granular Media-Based Tunable Passive Vibration Suppressor

    Science.gov (United States)

    Dillon, Robert P.; Davis, Gregory L.; Shapiro, Andrew A.; Borgonia, John Paul C.; Kahn, Daniel L.; Boechler, Nicholas; Boechler,, Chiara

    2013-01-01

    isolation (Figure 1). This configuration is referred to as a single-axis vibration suppressor. This invention also includes further designs for the integration of the single-axis vibration suppressor into a six-degree-of-freedom hexapod "Stewart"mounting configuration (Figure 2). By integrating each singleaxis vibration suppressor into a hexapod formation, a payload will be protected in all six degrees of freedom from shock and/or vibration. Additionally, to further enable the application of this device to multiple operational scenarios, particularly in the case of high loads, the vibration suppressor devices can be used in parallel in any array configuration.

  2. A STAT-1 knockout mouse model for Machupo virus pathogenesis

    Directory of Open Access Journals (Sweden)

    Shurtleff Amy C

    2011-06-01

    Full Text Available Abstract Background Machupo virus (MACV, a member of the Arenaviridae, causes Bolivian hemorrhagic fever, with ~20% lethality in humans. The pathogenesis of MACV infection is poorly understood, and there are no clinically proven treatments for disease. This is due, in part, to a paucity of small animal models for MACV infection in which to discover and explore candidate therapeutics. Methods Mice lacking signal transducer and activator of transcription 1 (STAT-1 were infected with MACV. Lethality, viral replication, metabolic changes, hematology, histopathology, and systemic cytokine expression were analyzed throughout the course of infection. Results We report here that STAT-1 knockout mice succumbed to MACV infection within 7-8 days, and presented some relevant clinical and histopathological manifestations of disease. Furthermore, the model was used to validate the efficacy of ribavirin in protection against infection. Conclusions The STAT-1 knockout mouse model can be a useful small animal model for drug testing and preliminary immunological analysis of lethal MACV infection.

  3. Efficient CRISPR/Cas9-based gene knockout in watermelon.

    Science.gov (United States)

    Tian, Shouwei; Jiang, Linjian; Gao, Qiang; Zhang, Jie; Zong, Mei; Zhang, Haiying; Ren, Yi; Guo, Shaogui; Gong, Guoyi; Liu, Fan; Xu, Yong

    2017-03-01

    CRISPR/Cas9 system can precisely edit genomic sequence and effectively create knockout mutations in T0 generation watermelon plants. Genome editing offers great advantage to reveal gene function and generate agronomically important mutations to crops. Recently, RNA-guided genome editing system using the type II clustered regularly interspaced short palindromic repeats (CRISPR)-associated protein 9 (Cas9) has been applied to several plant species, achieving successful targeted mutagenesis. Here, we report the genome of watermelon, an important fruit crop, can also be precisely edited by CRISPR/Cas9 system. ClPDS, phytoene desaturase in watermelon, was selected as the target gene because its mutant bears evident albino phenotype. CRISPR/Cas9 system performed genome editing, such as insertions or deletions at the expected position, in transfected watermelon protoplast cells. More importantly, all transgenic watermelon plants harbored ClPDS mutations and showed clear or mosaic albino phenotype, indicating that CRISPR/Cas9 system has technically 100% of genome editing efficiency in transgenic watermelon lines. Furthermore, there were very likely no off-target mutations, indicated by examining regions that were highly homologous to sgRNA sequences. Our results show that CRISPR/Cas9 system is a powerful tool to effectively create knockout mutations in watermelon.

  4. Proton-induced knockout reactions with polarized and unpolarized beams

    Science.gov (United States)

    Wakasa, T.; Ogata, K.; Noro, T.

    2017-09-01

    Proton-induced knockout reactions provide a direct means of studying the single particle or cluster structures of target nuclei. In addition, these knockout reactions are expected to play a unique role in investigations of the effects of the nuclear medium on nucleon-nucleon interactions as well as the properties of nucleons and mesons. However, due to the nature of hadron probes, these reactions can suffer significant disturbances from the nuclear surroundings and the quantitative theoretical treatment of such processes can also be challenging. In this article, we review the experimental and theoretical progress in this field, particularly focusing on the use of these reactions as a spectroscopic tool and as a way to examine the medium modification of nucleon-nucleon interactions. With regard to the former aspect, the review presents a semi-quantitative evaluation of these reactions based on existing experimental data. In terms of the latter point, we introduce a significant body of evidence that suggests, although does not conclusively prove, the existence of medium effects. In addition, this paper also provides information and comments on other related subjects.

  5. Cellular senescence and tumor suppressor gene p16.

    Science.gov (United States)

    Rayess, Hani; Wang, Marilene B; Srivatsan, Eri S

    2012-04-15

    Cellular senescence is an irreversible arrest of cell growth. Biochemical and morphological changes occur during cellular senescence, including the formation of a unique cellular morphology such as flattened cytoplasm. Function of mitochondria, endoplasmic reticulum and lysosomes are affected resulting in the inhibition of lysosomal and proteosomal pathways. Cellular senescence can be triggered by a number of factors including, aging, DNA damage, oncogene activation and oxidative stress. While the molecular mechanism of senescence involves p16 and p53 tumor suppressor genes and telomere shortening, this review is focused on the mechanism of p16 control. The p16-mediated senescence acts through the retinoblastoma (Rb) pathway inhibiting the action of the cyclin dependant kinases leading to G1 cell cycle arrest. Rb is maintained in a hypophosphorylated state resulting in the inhibition of transcription factor E2F1. Regulation of p16 expression is complex and involves epigenetic control and multiple transcription factors. PRC1 (Pombe repressor complex (1) and PRC2 (Pombe repressor complex (2) proteins and histone deacetylases play an important role in the promoter hypermethylation for suppressing p16 expression. While transcription factors YY1 and Id1 suppress p16 expression, transcription factors CTCF, Sp1 and Ets family members activate p16 transcription. Senescence occurs with the inactivation of suppressor elements leading to the enhanced expression of p16. Copyright © 2011 UICC.

  6. ABCE1 is a highly conserved RNA silencing suppressor.

    Directory of Open Access Journals (Sweden)

    Kairi Kärblane

    Full Text Available ATP-binding cassette sub-family E member 1 (ABCE1 is a highly conserved protein among eukaryotes and archaea. Recent studies have identified ABCE1 as a ribosome-recycling factor important for translation termination in mammalian cells, yeast and also archaea. Here we report another conserved function of ABCE1. We have previously described AtRLI2, the homolog of ABCE1 in the plant Arabidopsis thaliana, as an endogenous suppressor of RNA silencing. In this study we show that this function is conserved: human ABCE1 is able to suppress RNA silencing in Nicotiana benthamiana plants, in mammalian HEK293 cells and in the worm Caenorhabditis elegans. Using co-immunoprecipitation and mass spectrometry, we found a number of potential ABCE1-interacting proteins that might support its function as an endogenous suppressor of RNA interference. The interactor candidates are associated with epigenetic regulation, transcription, RNA processing and mRNA surveillance. In addition, one of the identified proteins is translin, which together with its binding partner TRAX supports RNA interference.

  7. Molecular genetic analysis of tumor suppressor genes in ovarian cancer

    International Nuclear Information System (INIS)

    Lee, Je Ho; Park, Sang Yun

    1992-04-01

    To examine the loci of putative tumor suppressor genes in ovarian cancers, we performed the molecular genetic analysis with fresh human ovarian cancers and observed the following data. Frequent allelic losses were observed on chromosomes 4p(42%), 6p(50%), 7p(43%), 8q(31%), 12p(38%), 12q(33%), 16p(33%), 16q(37%), and 19p(34%) in addition to the previously reported 6q, 11p, and 17p in ovarian caroinomas. we have used an additional probe, TCP10 to narrow down the deleted region on chromosome 6q. TCP10 was reported to be mapped to 6q 25-27. Allelic loss was found to be 40% in epithelial ovarian caroinomas. This finding suggests that chromosome 6q 24-27 is one of putative region haboring the tumor suppressor gene of epithelial ovarian cancer (particularly serous type). To examine the association between FAL(Fractional Allelic Loss) and histopathological features, the FAL value on each phenotypically different tumor was calculated as the ratio of the number of allelic losses versus the number of cases informative in each chromosomal arm. The average FALs for each phenotypically different tumor were: serous cystoadenocarcinomas. FAL=0.31 : mucinous 0.12 : and clear cell carcinoma. FAL=0.20. (Author)

  8. Structural characterization of suppressor lipids by high-resolution mass spectrometry

    DEFF Research Database (Denmark)

    Rovillos, Mary Joy; Pauling, Josch Konstantin; Hannibal-Bach, Hans Kristian

    2016-01-01

    RATIONALE: Suppressor lipids were originally identified in 1993 and reported to encompass six lipid classes that enable Saccharomyces cerevisiae to live without sphingolipids. Structural characterization, using non-mass spectrometric approaches, revealed that these suppressor lipids are very long...... chain fatty acid (VLCFA)-containing glycerophospholipids with polar head groups that are typically incorporated into sphingolipids. Here we report, for the first time, the structural characterization of the yeast suppressor lipids using high-resolution mass spectrometry. METHODS: Suppressor lipids were...... isolated by preparative chromatography and subjected to structural characterization using hybrid quadrupole time-of-flight and ion trap-orbitrap mass spectrometry. RESULTS: Our investigation recapitulates the overall structural features of the suppressor lipids and provides an in-depth characterization...

  9. Nonspecific suppressor T cells cause decreased mixed lymphocyte culture reactivity in bone marrow transplant patients

    Energy Technology Data Exchange (ETDEWEB)

    Harada, M.; Ueda, M.; Nakao, S.; Kondo, K.; Odaka, K.; Shiobara, S.; Matsue, K.; Mori, T.; Matsuda, T.

    1986-07-15

    Decreased reactivity in mixed lymphocyte culture (MLC) was observed in patients within 1 yr after allogeneic and autologous bone marrow transplantation. Suppressor activity of peripheral blood mononuclear cells (PBMC) from transplant patients was studied by adding these cells as modulator cells to a bidirectional MLC with cells from normal individuals. PBMC from transplant patients markedly suppressed MLC reactivity in a dose-dependent manner. Suppressor activity was present in cells forming rosettes with sheep erythrocytes. Treatment of modulator cells with monoclonal antibodies against T cell differentiation antigens (OKT8, OKIa1) and complement completely abolished suppression of MLC. Suppressor activity was unaffected by 30 Gy irradiation. Suppressor activity declined gradually after transplantation and was inversely correlated with MLC reactivity of each patient at a significant level (p less than 0.01). These observations suggest that OKT8+ Ia+ radioresistant suppressor T cells play a role in the development of decreased MLC reactivity observed during the early post-transplant period.

  10. Determination of Heritage SSME Pogo Suppressor Resistance and Inertance from Waterflow Pulse Testing

    Science.gov (United States)

    McDougal, Chris; Eberhart, Chad; Lee, Erik

    2016-01-01

    Waterflow tests of a heritage Space Shuttle Main Engine pogo suppressor were performed to experimentally quantify the resistance and inertance provided by the suppressor. Measurements of dynamic pressure and flow rate in response to pulsing flow were made throughout the test loop. A unique system identification methodology combined all sensor measurements with a one-dimensional perturbational flow model of the complete water flow loop to spatially translate physical measurements to the device under test. Multiple techniques were then employed to extract the effective resistance and inertance for the pogo suppressor. Parameters such as steady flow rate, perturbational flow rate magnitude, and pulse frequency were investigated to assess their influence on the behavior of the pogo suppressor dynamic response. These results support validation of the RS-25 pogo suppressor performance for use on the Space Launch System Core Stage.

  11. Small RNA binding is a common strategy to suppress RNA silencing by several viral suppressors

    Science.gov (United States)

    Lakatos, Lóránt; Csorba, Tibor; Pantaleo, Vitantonio; Chapman, Elisabeth J; Carrington, James C; Liu, Yu-Ping; Dolja, Valerian V; Calvino, Lourdes Fernández; López-Moya, Juan José; Burgyán, József

    2006-01-01

    RNA silencing is an evolutionarily conserved system that functions as an antiviral mechanism in higher plants and insects. To counteract RNA silencing, viruses express silencing suppressors that interfere with both siRNA- and microRNA-guided silencing pathways. We used comparative in vitro and in vivo approaches to analyse the molecular mechanism of suppression by three well-studied silencing suppressors. We found that silencing suppressors p19, p21 and HC-Pro each inhibit the intermediate step of RNA silencing via binding to siRNAs, although the molecular features required for duplex siRNA binding differ among the three proteins. None of the suppressors affected the activity of preassembled RISC complexes. In contrast, each suppressor uniformly inhibited the siRNA-initiated RISC assembly pathway by preventing RNA silencing initiator complex formation. PMID:16724105

  12. Bone phenotypes of P2 receptor knockout mice

    DEFF Research Database (Denmark)

    Orriss, Isabel; Syberg, Susanne; Wang, Ning

    2011-01-01

    The action of extracellular nucleotides is mediated by ionotropic P2X receptors and G-protein coupled P2Y receptors. The human genome contains 7 P2X and 8 P2Y receptor genes. Knockout mice strains are available for most of them. As their phenotypic analysis is progressing, bone abnormalities have...... been observed in an impressive number of these mice: distinct abnormalities in P2X7-/- mice, depending on the gene targeting construct and the genetic background, decreased bone mass in P2Y1-/- mice, increased bone mass in P2Y2-/- mice, decreased bone resorption in P2Y6-/- mice, decreased bone...... formation and bone resorption in P2Y13-/- mice. These findings demonstrate the unexpected importance of extracellular nucleotide signalling in the regulation of bone metabolism via multiple P2 receptors and distinct mechanisms involving both osteoblasts and osteoclasts....

  13. Antiatherogenic effects of oleanolic acid in apolipoprotein E knockout mice

    DEFF Research Database (Denmark)

    Buus, Niels Henrik; Hansson, Nicolaj Christopher; Rodriguez-Rodriguez, Rosalia

    2011-01-01

    Oleanolic acid (OA) is a plant triterpenoid steroid with potentially antiatherogenic properties. We investigated whether OA affected atherosclerosis development and vascular function in apolipoprotein E knockout (ApoE(-/-)) mice. ApoE(-/-) mice were fed a high cholesterol Western-type diet...... in combination with OA (100 mg/kg/day), fluvastatin (5 mg/kg/day) or vehicle, with wild type (WT) mice serving as controls. After 8 weeks of treatment atherosclerotic plaque areas in the aortic arch and plasma lipid concentrations were determined. Vasoconstriction and relaxation of the proximal part of aorta...... were investigated in vitro. Inducible nitric oxide synthase (iNOS) was visualized using immunoblotting. As opposed to WT and fluvastatin- and vehicle-treated mice, OA-fed ApoE(-/-) mice gained no weight during the treatment period. Plasma concentrations of total-cholesterol and triglyceride were...

  14. Patched Knockout Mouse Models of Basal Cell Carcinoma

    Directory of Open Access Journals (Sweden)

    Frauke Nitzki

    2012-01-01

    Full Text Available Basal cell carcinoma (BCC is the most common human tumor. Mutations in the hedgehog (HH receptor Patched (PTCH are the main cause of BCC. Due to their high and increasing incidence, BCC are becoming all the more important for the health care system. Adequate animal models are required for the improvement of current treatment strategies. A good model should reflect the situation in humans (i.e., BCC initiation due to Ptch mutations on an immunocompetent background and should allow for (i BCC induction at a defined time point, (ii analysis of defined BCC stages, and (iii induction of BCC in 100% of animals. In addition, it should be easy to handle. Here, we compare several currently existing conventional and conditional Ptch knockout mouse models for BCC and their potential use in preclinical research. In addition, we provide new data using conditional Ptchflox/flox mice and the K5-Cre-ERT+/− driver.

  15. Drop tests of the Three Mile Island knockout canister

    International Nuclear Information System (INIS)

    Box, W.D.; Aaron, W.S.; Shappert, L.B.; Childress, P.C.; Quinn, G.J.; Smith, J.V.

    1987-01-01

    A type of Three Mile Island Unit 2 (TMI-2) defueling canister, called a ''knockout'' canister, was subjected to a series of drop tests at the Oak Ridge National Laboratory's Drop Test Facility. These tests confirmed the structural integrity of internal fixed neutron poisons in support of a request for NRC licensing of this type of canister for the shipment of TMI-2 reactor fuel debris to the Idaho National Engineering Laboratory (INEL) for the Core Examination R and D Program. This report presents the data generated and the results obtained from a series of four drop tests that included two drops with the test assembly in the vertical position and two drops with the assembly in the horizontal position

  16. Medium effects on spin observables of proton knockout reactions

    Energy Technology Data Exchange (ETDEWEB)

    Krein, G. [Instituto de Fisica Teorica (IFT), Sao Paulo, SP (Brazil); Maris, T.A.J.; Rodrigues, B.B.; Veit, E.A. [Rio Grande do Sul Univ., Porto Alegre, RS (Brazil). Inst. de Fisica

    1994-07-01

    Medium modifications of the properties of bound nucleons and mesons are investigated by means of medium energy quasi free proton knockout reactions with polarized incident protons. The sensitivity of the spin observables of these reactions to modifications of the nucleon and meson properties is studied using the Bonn one-boson exchange model of the nucleon-nucleon interaction. A method proposed to extract the pp analysing power in medium from the (p, 2 p) asymmetries indicates a reduction of this quantity compared to its free space value. This reduction is linked to modifications of masses and coupling constants of the nucleons and mesons in the nucleus. The implications of these modifications for another spin observable to be measured in the future are discussed. (author). 39 refs, 9 figs.

  17. Piroxicam treatment augments bone abnormalities in interleukin-10 knockout mice

    DEFF Research Database (Denmark)

    Holgersen, Kristine; Dobie, Ross; Farquharson, Colin

    2015-01-01

    BACKGROUND: Osteoporosis and fractures are common complications of inflammatory bowel disease. The pathogenesis is multifactorial and has been partly attributed to intestinal inflammation. The aim of this study was to evaluate bone status and assess the association between bone loss and gut...... inflammation in an experimental colitis model. METHODS: Colitis was induced in interleukin-10 knockout mice (PAC IL-10 k.o.) by peroral administration of piroxicam for 12 days. The degree of colitis was assessed by clinical, macroscopic, and microscopic evaluation. Trabecular and cortical bone...... microarchitecture of tibia were determined using micro-computed tomography. Moreover, the serum levels of bone formation and bone resorption biomarkers were measured, and inflammatory protein profiling was performed on colons. RESULTS: PAC IL-10 k.o. mice developed severe colitis, characterized by hyperplasia...

  18. Preaxial Polydactyly in Sost/Sostdc1 Double Knockouts

    Energy Technology Data Exchange (ETDEWEB)

    Yee, C M; Collette, N M; Loots, G G

    2011-07-29

    In the United States, {approx}5% are born with congenital birth defects due to abnormal function of cellular processes and interactions. Sclerosteosis, a rare autosomal recessive disease, causes hyperostosis of the axial and appendicular skeleton, and patients present radial deviation, digit syndactyly, nail dysplasia, and overall high bone mineral density. Sclerosteosis is due to a loss of function of sclerostin (Sost). Sost is a Wnt (abbrev.) antagonist; when mutated, nonfunctional Sost results in hyperactive osteoblast activity which leads to abnormal high bone mass. Previous studies have shown that Sost overexpression in transgenic mice causes reduced bone mineral density and a variety of limb phenotypes ranging from lost, fused, and split phalanges. Consistent with clinical manifestations of Sclerosteosis, Sost knockout mice exhibit increased generalized bone mineral density and syndactyly of the digits. Sostdc1 is a paralog of Sost that has also been described as an antagonist of Wnt signaling, in developing tooth buds. Unlike Sost knockouts, Sostdc1 null mice do not display any limb abnormalities. To determine if Sost and Sostdc1 have redundant functions during limb patterning, we examined Sost; Sostdc1 mice determined that they exhibit a novel preaxial polydactyly phenotype with a low penetrance. LacZ staining, skeletal preparations, and in situ hybridization experiments were used to help characterize this novel phenotype and understand how this phenotype develops. We find Sost and Sostdc1 to have complementary expression patterns during limb development, and the loss of their expression alters the transcription of several key limb regulators, such as Fgf8, Shh and Grem.

  19. Establishment of pten knockout medaka with transcription activator-like effector nucleases (TALENs as a model of PTEN deficiency disease.

    Directory of Open Access Journals (Sweden)

    Yuriko Matsuzaki

    Full Text Available Phosphatase and tensin homolog (PTEN is a lipid and protein phosphatase that antagonizes signaling by the phosphatidylinositol 3-kinase (PI3K-AKT signaling pathway. The PTEN gene is a major tumor suppressor, with mutations of this gene occurring frequently in tumors of humans and mice. We have now developed mutant medaka deficient in PTEN with the use of transcription activator-like effector nuclease (TALEN technology. Medaka possesses two pten genes, ptena and ptenb, similar to zebrafish. We established 16 ptena mutant lines and two ptenb mutant lines. Homozygous single pten mutants were found to be viable and fertile. In contrast, pten double-knockout (dko embryos manifested severe abnormalities in vasculogenesis, eye size, and tail development at 72 hours post fertilization(hpf and died before hatching. Immunoblot analysis revealed that the ratio of phosphorylated to total forms of AKT (pAKT/AKT in pten dko embryos was four times that in wild-type embryos, indicative of up-regulation of signaling by the PI3K-AKT pathway. Treatment of pten dko embryos with the PI3K inhibitor LY294002 reduced the pAKT/AKT ratio by about one-half and partially rescued the defect in vasculogenesis. Additional inhibitors of the PI3K-AKT pathway, including rapamycin and N-α-tosyl-L-phenylalanyl chloromethyl ketone, also partially restored vasculogenesis in the dko embryos. Our model system thus allows pten dko embryos to be readily distinguished from wild-type embryos at an early stage of development and is suitable for the screening of drugs able to compensate for PTEN deficiency.

  20. Crossover suppressors and balanced recessive lethals in Caenorhabditis elegans

    International Nuclear Information System (INIS)

    Herman, R.K.

    1978-01-01

    Two dominant suppressors of crossing over have been identified following x-ray treatment of the small nematode C. elegans. They suppress crossing over in linkage group II (LGII) about 100-fold and 50-fold and are both tightly linked to LGII markers. One, called C1, segregates independently of all other linkage groups and is homozygous fertile. The other is a translocation involving LGII and X. The translocation also suppresses crossing over along the right half of X and is homozygous lethal. C1 has been used as a balancer of LGII recessive lethal and sterile mutations induced by EMS. The frequencies of occurrence of lethals and steriles were approximately equal. Fourteen mutations were assigned to complementation groups and mapped. They tended to map in the same region where LGII visibles are clustered

  1. RhoB: Team Oncogene or Team Tumor Suppressor?

    Science.gov (United States)

    Ju, Julia A; Gilkes, Daniele M

    2018-01-30

    Although Rho GTPases RhoA, RhoB, and RhoC share more than 85% amino acid sequence identity, they play very distinct roles in tumor progression. RhoA and RhoC have been suggested in many studies to contribute positively to tumor development, but the role of RhoB in cancer remains elusive. RhoB contains a unique C-terminal region that undergoes specific post-translational modifications affecting its localization and function. In contrast to RhoA and RhoC, RhoB not only localizes at the plasma membrane, but also on endosomes, multivesicular bodies and has even been identified in the nucleus. These unique features are what contribute to the diversity and potentially opposing functions of RhoB in the tumor microenvironment. Here, we discuss the dualistic role that RhoB plays as both an oncogene and tumor suppressor in the context of cancer development and progression.

  2. Myeloid derived suppressor cells as therapeutic target in hematological malignancies

    Directory of Open Access Journals (Sweden)

    Kim eDe Veirman

    2014-12-01

    Full Text Available Myeloid derived suppressor cells (MDSC are a heterogeneous population of immature myeloid cells that accumulate during pathological conditions such as cancer and are associated with a poor clinical outcome. MDSC expansion hampers the host anti-tumor immune response by inhibition of T cell proliferation, cytokine secretion and recruitment of regulatory T cells. In addition, MDSC exert non-immunological functions including the promotion of angiogenesis, tumor invasion and metastasis. Recent years, MDSC are considered as a potential target in solid tumors and hematological malignancies to enhance the effects of currently used immune modulating agents. This review focuses on the characteristics, distribution, functions, cell-cell interactions and targeting of MDSC in hematological malignancies including multiple myeloma, lymphoma and leukemia.

  3. p53 tumor suppressor gene: significance in neoplasia - a review

    International Nuclear Information System (INIS)

    Alam, J.M.

    2000-01-01

    p53 is a tumor suppressor gene located on chromosome 17p13.1. Its function includes cell cycle control and apoptosis. Loss of p53 function, either due to decreased level or genetic transformation, is associated with loss of cell cycle control, decrease, apoptosis and genomic modification, such mutation of p53 gene is now assessed and the indicator of neoplasia of cancer of several organs and cell types, p53 has demonstrated to have critical role in defining various progressive stages of neoplasia, therapeutic strategies and clinical application. The present review briefly describes function of p53 in addition to its diagnostic and prognostic significance in detecting several types of neoplasia. (author)

  4. Classical Oncogenes and Tumor Suppressor Genes: A Comparative Genomics Perspective

    Directory of Open Access Journals (Sweden)

    Oxana K. Pickeral

    2000-05-01

    Full Text Available We have curated a reference set of cancer-related genes and reanalyzed their sequences in the light of molecular information and resources that have become available since they were first cloned. Homology studies were carried out for human oncogenes and tumor suppressors, compared with the complete proteome of the nematode, Caenorhabditis elegans, and partial proteomes of mouse and rat and the fruit fly, Drosophila melanogaster. Our results demonstrate that simple, semi-automated bioinformatics approaches to identifying putative functionally equivalent gene products in different organisms may often be misleading. An electronic supplement to this article1 provides an integrated view of our comparative genomics analysis as well as mapping data, physical cDNA resources and links to published literature and reviews, thus creating a “window” into the genomes of humans and other organisms for cancer biology.

  5. Identification of an MLC suppressor cell population in acute leukemia

    International Nuclear Information System (INIS)

    Bryan, C.F.; Broxmeyer, H.E.; Hansen, J.; Pollack, M.; Dupont, B.

    1978-01-01

    The MLC data from the 20 nonsuppressing patients and the 10 suppressing leukemia patients were analyzed with regard to HLA-A, -B, and -C antigens in the leukemia patients and compared with the presence or absence of suppression. These results demonstrate a significant increase (p < 0.02, Mann-Whitney U test) of HLA antigens Al, A3, and A11 in the leukemia suppressor group. Seven of the 10 leukemia patients showing suppression were A1, A3, or A11, while only 4 of the 20 nonsuppressing leukemia patients carried any of these three HLA-A antigens. The studies demonstrate that a nonspecific suppression of MLC responses is observed in 33% of the patients with acute leukemia

  6. Complexes between the LKB1 tumor suppressor, STRADα/β and MO25α/β are upstream kinases in the AMP-activated protein kinase cascade

    Directory of Open Access Journals (Sweden)

    Alessi Dario R

    2003-09-01

    Full Text Available Abstract Background The AMP-activated protein kinase (AMPK cascade is a sensor of cellular energy charge that acts as a 'metabolic master switch' and inhibits cell proliferation. Activation requires phosphorylation of Thr172 of AMPK within the activation loop by upstream kinases (AMPKKs that have not been identified. Recently, we identified three related protein kinases acting upstream of the yeast homolog of AMPK. Although they do not have obvious mammalian homologs, they are related to LKB1, a tumor suppressor that is mutated in the human Peutz-Jeghers cancer syndrome. We recently showed that LKB1 exists as a complex with two accessory subunits, STRADα/β and MO25α/β. Results We report the following observations. First, two AMPKK activities purified from rat liver contain LKB1, STRADα and MO25α, and can be immunoprecipitated using anti-LKB1 antibodies. Second, both endogenous and recombinant complexes of LKB1, STRADα/β and MO25α/β activate AMPK via phosphorylation of Thr172. Third, catalytically active LKB1, STRADα or STRADβ and MO25α or MO25β are required for full activity. Fourth, the AMPK-activating drugs AICA riboside and phenformin do not activate AMPK in HeLa cells (which lack LKB1, but activation can be restored by stably expressing wild-type, but not catalytically inactive, LKB1. Fifth, AICA riboside and phenformin fail to activate AMPK in immortalized fibroblasts from LKB1-knockout mouse embryos. Conclusions These results provide the first description of a physiological substrate for the LKB1 tumor suppressor and suggest that it functions as an upstream regulator of AMPK. Our findings indicate that the tumors in Peutz-Jeghers syndrome could result from deficient activation of AMPK as a consequence of LKB1 inactivation.

  7. Altered Sleep Homeostasis in Rev-erbα Knockout Mice

    Science.gov (United States)

    Mang, Géraldine M.; La Spada, Francesco; Emmenegger, Yann; Chappuis, Sylvie; Ripperger, Jürgen A.; Albrecht, Urs; Franken, Paul

    2016-01-01

    Study Objectives: The nuclear receptor REV-ERBα is a potent, constitutive transcriptional repressor critical for the regulation of key circadian and metabolic genes. Recently, REV-ERBα's involvement in learning, neurogenesis, mood, and dopamine turnover was demonstrated suggesting a specific role in central nervous system functioning. We have previously shown that the brain expression of several core clock genes, including Rev-erbα, is modulated by sleep loss. We here test the consequences of a loss of REV-ERBα on the homeostatic regulation of sleep. Methods: EEG/EMG signals were recorded in Rev-erbα knockout (KO) mice and their wild type (WT) littermates during baseline, sleep deprivation, and recovery. Cortical gene expression measurements after sleep deprivation were contrasted to baseline. Results: Although baseline sleep/wake duration was remarkably similar, KO mice showed an advance of the sleep/wake distribution relative to the light-dark cycle. After sleep onset in baseline and after sleep deprivation, both EEG delta power (1–4 Hz) and sleep consolidation were reduced in KO mice indicating a slower increase of homeostatic sleep need during wakefulness. This slower increase might relate to the smaller increase in theta and gamma power observed in the waking EEG prior to sleep onset under both conditions. Indeed, the increased theta activity during wakefulness predicted delta power in subsequent NREM sleep. Lack of Rev-erbα increased Bmal1, Npas2, Clock, and Fabp7 expression, confirming the direct regulation of these genes by REV-ERBα also in the brain. Conclusions: Our results add further proof to the notion that clock genes are involved in sleep homeostasis. Because accumulating evidence directly links REV-ERBα to dopamine signaling the altered homeostatic regulation of sleep reported here are discussed in that context. Citation: Mang GM, La Spada F, Emmenegger Y, Chappuis S, Ripperger JA, Albrecht U, Franken P. Altered sleep homeostasis in Rev

  8. PML tumor suppressor protein is required for HCV production

    Energy Technology Data Exchange (ETDEWEB)

    Kuroki, Misao [Department of Tumor Virology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, 2-5-1, Shikata-cho, Okayama 700-8558 (Japan); Research Fellow of the Japan Society for the Promotion of Science (Japan); Center for AIDS Research, Kumamoto University, Kumamoto 860-0811 (Japan); Ariumi, Yasuo, E-mail: ariumi@kumamoto-u.ac.jp [Department of Tumor Virology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, 2-5-1, Shikata-cho, Okayama 700-8558 (Japan); Center for AIDS Research, Kumamoto University, Kumamoto 860-0811 (Japan); Hijikata, Makoto [Department of Viral Oncology, Institute for Virus Research, Kyoto University, Kyoto 606-8507 (Japan); Ikeda, Masanori; Dansako, Hiromichi [Department of Tumor Virology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, 2-5-1, Shikata-cho, Okayama 700-8558 (Japan); Wakita, Takaji [Department of Virology II, National Institute of Infectious Diseases, Tokyo 162-8640 (Japan); Shimotohno, Kunitada [Research Center for Hepatitis and Immunology, National Center for Global Health and Medicine, Ichikawa, Chiba 272-8516 (Japan); Kato, Nobuyuki [Department of Tumor Virology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, 2-5-1, Shikata-cho, Okayama 700-8558 (Japan)

    2013-01-11

    Highlights: Black-Right-Pointing-Pointer PML tumor suppressor protein is required for HCV production. Black-Right-Pointing-Pointer PML is dispensable for HCV RNA replication. Black-Right-Pointing-Pointer HCV could not alter formation of PML-NBs. Black-Right-Pointing-Pointer INI1 and DDX5, PML-related proteins, are involved in HCV life cycle. -- Abstract: PML tumor suppressor protein, which forms discrete nuclear structures termed PML-nuclear bodies, has been associated with several cellular functions, including cell proliferation, apoptosis and antiviral defense. Recently, it was reported that the HCV core protein colocalizes with PML in PML-NBs and abrogates the PML function through interaction with PML. However, role(s) of PML in HCV life cycle is unknown. To test whether or not PML affects HCV life cycle, we examined the level of secreted HCV core and the infectivity of HCV in the culture supernatants as well as the level of HCV RNA in HuH-7-derived RSc cells, in which HCV-JFH1 can infect and efficiently replicate, stably expressing short hairpin RNA targeted to PML. In this context, the level of secreted HCV core and the infectivity in the supernatants from PML knockdown cells was remarkably reduced, whereas the level of HCV RNA in the PML knockdown cells was not significantly affected in spite of very effective knockdown of PML. In fact, we showed that PML is unrelated to HCV RNA replication using the subgenomic HCV-JFH1 replicon RNA, JRN/3-5B. Furthermore, the infectivity of HCV-like particle in the culture supernatants was significantly reduced in PML knockdown JRN/3-5B cells expressing core to NS2 coding region of HCV-JFH1 genome using the trans-packaging system. Finally, we also demonstrated that INI1 and DDX5, the PML-related proteins, are involved in HCV production. Taken together, these findings suggest that PML is required for HCV production.

  9. Immunosympathectomy as the first phenotypic knockout with antibodies.

    Science.gov (United States)

    Cattaneo, Antonino

    2013-03-26

    In a PNAS Classic Article published in 1960, Rita Levi-Montalcini offered formal and conclusive proof that endogenous NGF was responsible for the survival of sympathetic neurons in vivo. Thus ended an experimental tour de force lasting a decade, starting with the demonstration that a humoral factor, produced from a tumor transplanted in a chicken embryo, was responsible for stimulating outgrowth of nerve fibers from sympathetic and sensory neurons. From a more general methodological point of view, this work provided a breakthrough in the quest to achieve targeted loss of function and experimentally validate the function of biological molecules. Finally, this work provided an example of the ablation of a specific neuronal subpopulation in an otherwise intact nervous system, an immunological knife of unsurpassed effectiveness and precision. The novelty and the importance of the PNAS Classic Article is discussed here, collocating it within the context of the particular moment of the NGF discovery saga, of Rita Levi-Montalcini's scientific and academic career, and of the general scientific context of those years. This seminal work, involving the use of antibodies for phenotypic knockout in vivo, planted seeds that were to bear new fruit many years later with the advent of monoclonal antibodies and recombinant antibody technologies.

  10. Arterial injury promotes medial chondrogenesis in Sm22 knockout mice.

    Science.gov (United States)

    Shen, Jianbin; Yang, Maozhou; Jiang, Hong; Ju, Donghong; Zheng, Jian-Pu; Xu, Zhonghui; Liao, Tang-Dong; Li, Li

    2011-04-01

    Expression of SM22 (also known as SM22alpha and transgelin), a vascular smooth muscle cells (VSMCs) marker, is down-regulated in arterial diseases involving medial osteochondrogenesis. We investigated the effect of SM22 deficiency in a mouse artery injury model to determine the role of SM22 in arterial chondrogenesis. Sm22 knockout (Sm22(-/-)) mice developed prominent medial chondrogenesis 2 weeks after carotid denudation as evidenced by the enhanced expression of chondrogenic markers including type II collagen, aggrecan, osteopontin, bone morphogenetic protein 2, and SRY-box containing gene 9 (SOX9). This was concomitant with suppression of VSMC key transcription factor myocardin and of VSMC markers such as SM α-actin and myosin heavy chain. The conversion tendency from myogenesis to chondrogenesis was also observed in primary Sm22(-/-) VSMCs and in a VSMC line after Sm22 knockdown: SM22 deficiency altered VSMC morphology with compromised stress fibre formation and increased actin dynamics. Meanwhile, the expression level of Sox9 mRNA was up-regulated while the mRNA levels of myocardin and VSMC markers were down-regulated, indicating a pro-chondrogenic transcriptional switch in SM22-deficient VSMCs. Furthermore, the increased expression of SOX9 was mediated by enhanced reactive oxygen species production and nuclear factor-κB pathway activation. These findings suggest that disruption of SM22 alters the actin cytoskeleton and promotes chondrogenic conversion of VSMCs.

  11. Modeling fragile X syndrome in the Fmr1 knockout mouse

    Science.gov (United States)

    Kazdoba, Tatiana M.; Leach, Prescott T.; Silverman, Jill L.; Crawley, Jacqueline N.

    2014-01-01

    Summary Fragile X Syndrome (FXS) is a commonly inherited form of intellectual disability and one of the leading genetic causes for autism spectrum disorder. Clinical symptoms of FXS can include impaired cognition, anxiety, hyperactivity, social phobia, and repetitive behaviors. FXS is caused by a CGG repeat mutation which expands a region on the X chromosome containing the FMR1 gene. In FXS, a full mutation (> 200 repeats) leads to hypermethylation of FMR1, an epigenetic mechanism that effectively silences FMR1 gene expression and reduces levels of the FMR1 gene product, fragile X mental retardation protein (FMRP). FMRP is an RNA-binding protein that is important for the regulation of protein expression. In an effort to further understand how loss of FMR1 and FMRP contribute to FXS symptomology, several FXS animal models have been created. The most well characterized rodent model is the Fmr1 knockout (KO) mouse, which lacks FMRP protein due to a disruption in its Fmr1 gene. Here, we review the behavioral phenotyping of the Fmr1 KO mouse to date, and discuss the clinical relevance of this mouse model to the human FXS condition. While much remains to be learned about FXS, the Fmr1 KO mouse is a valuable tool for understanding the repercussions of functional loss of FMRP and assessing the efficacy of pharmacological compounds in ameliorating the molecular and behavioral phenotypes relevant to FXS. PMID:25606362

  12. Pheochromocytoma cell lines from heterozygous neurofibromatosis knockout mice.

    Science.gov (United States)

    Powers, J F; Evinger, M J; Tsokas, P; Bedri, S; Alroy, J; Shahsavari, M; Tischler, A S

    2000-12-01

    Transplantable tumors and cell lines have been developed from pheochromocytomas arising in mice with a heterozygous knockout mutation of the neurofibromatosis gene, Nf1. Nf1 encodes a ras-GTPase-activating protein, neurofibromin, and mouse pheochromocytoma (MPC) cells in primary cultures typically show extensive spontaneous neuronal differentiation that may result from the loss of the remaining wild-type allele and defective regulation of ras signaling. However, all MPC cell lines express neurofibromin, suggesting that preservation of the wild-type allele may be required to permit the propagation of MPC cells in vitro. MPC lines differ from PC12 cells in that they express both endogenous phenylethanolamine N-methyltransferase (PNMT) and full-length PNMT reporter constructs. PNMT expression is increased by dexamethasone and by cell-cell contact in suspension cultures. Mouse pheochromocytomas are a new tool for studying genes and signaling pathways that regulate cell growth and differentiation in adrenal medullary neoplasms and are a unique model for studying the regulation of PNMT expression.

  13. Orexin knockout mice exhibit impaired spatial working memory.

    Science.gov (United States)

    Dang, Ruozhi; Chen, Qiuhan; Song, Jie; He, Chao; Zhang, Jun; Xia, Jianxia; Hu, Zhian

    2018-03-06

    Orexins play a crucial role in the maintenance of arousal and are involved in the modulation of diverse physiological process, including cognitive function. Recent data have suggested that orexins are involved in learning and memory processes. The purpose of this study was to assess the effects of orexin deficiency on working memory. A delayed non-matching-to-place T-maze task was used to evaluate spatial working memory in mice lacking orexin prepro-peptide (orexin knockout; KO) and wild-type controls. We demonstrated that the number of correct choices in the orexin KO mice became lower than that of the controls over training. In an object exploration task, the controls explored the displaced object more than the mutants did, whereas this difference was not observed for the nondisplaced objects in either group. The orexin KO mice showed locomotor activity comparable to the control mice in terms of total distance traveled across training in both the object exploration task and the open field test. These findings indicate that the orexin system plays an important role in working memory of spatial cues. Copyright © 2018 Elsevier B.V. All rights reserved.

  14. Bone growth and turnover in progesterone receptor knockout mice.

    Energy Technology Data Exchange (ETDEWEB)

    Rickard, David J.; Iwaniec, Urszula T.; Evans, Glenda; Hefferan, Theresa E.; Hunter, Jaime C.; Waters, Katrina M.; Lydon, John P.; O' Malley, Bert W.; Khosla, Sundeep; Spelsberg, Thomas C.; Turner, Russell T.

    2008-05-01

    The role of progesterone receptor (PR) signaling in skeletal metabolism is controversial. To address whether signaling through the PR is necessary for normal bone growth and turnover, we performed histomorphometric and mCT analyses of bone from homozygous female PR knockout (PRKO) mice at 6, 12, and 26 weeks of age. These mice possess a null mutation of the PR locus, which blocks the gene expression of A and B isoforms of PR. Body weight gain, uterine weight gain and tibia longitudinal bone growth was normal in PRKO mice. In contrast, total and cortical bone mass were increased in long bones of post-pubertal (12 and 26-week-old) PRKO mice, whereas cancellous bone mass was normal in the tibia but increased in the humerus. The striking 57% decrease in cancellous bone from the proximal tibia metaphysis which occurred between 6 and 26 weeks in WT mice was abolished in PRKO mice. The improved bone balance in aging PRKO mice was associated with elevated bone formation and a tendency toward reduced osteoclast perimeter. Taken together, these findings suggest that PR signaling in mice attenuates the accumulation of cortical bone mass during adolescence and is required for early age-related loss of cancellous bone.

  15. Identification of a large set of rare complete human knockouts.

    Science.gov (United States)

    Sulem, Patrick; Helgason, Hannes; Oddson, Asmundur; Stefansson, Hreinn; Gudjonsson, Sigurjon A; Zink, Florian; Hjartarson, Eirikur; Sigurdsson, Gunnar Th; Jonasdottir, Adalbjorg; Jonasdottir, Aslaug; Sigurdsson, Asgeir; Magnusson, Olafur Th; Kong, Augustine; Helgason, Agnar; Holm, Hilma; Thorsteinsdottir, Unnur; Masson, Gisli; Gudbjartsson, Daniel F; Stefansson, Kari

    2015-05-01

    Loss-of-function mutations cause many mendelian diseases. Here we aimed to create a catalog of autosomal genes that are completely knocked out in humans by rare loss-of-function mutations. We sequenced the whole genomes of 2,636 Icelanders and imputed the sequence variants identified in this set into 101,584 additional chip-genotyped and phased Icelanders. We found a total of 6,795 autosomal loss-of-function SNPs and indels in 4,924 genes. Of the genotyped Icelanders, 7.7% are homozygotes or compound heterozygotes for loss-of-function mutations with a minor allele frequency (MAF) below 2% in 1,171 genes (complete knockouts). Genes that are highly expressed in the brain are less often completely knocked out than other genes. Homozygous loss-of-function offspring of two heterozygous parents occurred less frequently than expected (deficit of 136 per 10,000 transmissions for variants with MAF <2%, 95% confidence interval (CI) = 10-261).

  16. Suppressor Effects of Positive and Negative Religious Coping on Academic Burnout Among Korean Middle School Students.

    Science.gov (United States)

    Noh, Hyunkyung; Chang, Eunbi; Jang, Yoojin; Lee, Ji Hae; Lee, Sang Min

    2016-02-01

    Statistical suppressor effects in prediction models can provide evidence of the interdependent relationship of independent variables. In this study, the suppressor effects of positive and negative religious coping on academic burnout were examined using longitudinal data. First, 388 middle school students reported their type of religion and use of positive and negative religious coping strategies. Four months later, they also reported their level of academic burnout. From structural equation modeling, significant suppressor effects were found among religious students. That is, the coefficients became larger when both positive and negative religious coping predicted academic burnout simultaneously, compared to when each religious coping predicted academic burnout alone. However, suppressor effects were not found among non-religious students.

  17. Restoring Sensitivity to Apoptosis in Prostate Cancer Cells by Reconstitution of the Tumor Suppressor PTEN

    National Research Council Canada - National Science Library

    Whang, Young

    2003-01-01

    ... suppressor PTEN in regulating sensitivity to apoptosis in prostate cancer. We have previously shown that loss of HEN function leads to excessive antiapoptotic signaling through constitutive activation of the Akt protein kinase...

  18. The Function of PTEN Tumor Suppressor Gene in Prostate Cancer Development

    National Research Council Canada - National Science Library

    Wu, Hong

    2001-01-01

    .... The recently identified tumor suppressor gene PTEN is a promising candidate for being involved in prostate cancer since it is frequently deleted in prostate cancer, especially in advanced or metastatic forms...

  19. The Function of PTEN Tumor Suppressor Gene in Prostate Cancer Development

    National Research Council Canada - National Science Library

    Wu, Hong

    2002-01-01

    .... The recently identified tumor suppressor gene PTEN is a promising candidate for being involved in prostate cancer since it is frequently deleted in prostate cancer, especially in advanced or metastatic forms...

  20. The Tumor Suppressor Protein TEP1/PTEN/MMAC1 and Human Breast Cancer

    National Research Council Canada - National Science Library

    Sun, Hong

    2002-01-01

    PTEN is an important tumor suppressor. Both inherited mutations and somatic mutations in the PTEN gene have been frequently found in a variety of human cancers, including the breast cancer, PTEN protein has been shown to possess...

  1. The effect of suppressors and muzzle brakes on shock wave strength

    Science.gov (United States)

    Phan, K. C.; Stollery, J. L.

    Experimental simulations of a gun blast were performed in the course of an optimization study of shock-wave suppressor and muzzle-brake geometry. A single-spark schlieren system was used to photograph the shock waves emerging from a 32-mm shock tube. The suppressor systems tested with respect to the overpressure level included a perforated tube enclosed in an expansion chamber, a cup-and-box suppressor, and noise-absorbent materials inside a suppressor; high suppression efficiency was observed for the first two. Recoil simulation tests, performed with plain and pyramidal baffles, disk, and cylinder, show that the blast level is generally higher for a more efective muzzle brake. An optimum distance from the muzzle to the brake is suggested to be in the region of one caliber.

  2. 99: A Novel Myc-Interacting Protein with Features of a Breast Tumor Suppressor Gene Product

    National Research Council Canada - National Science Library

    Prendergast, George

    1997-01-01

    Bin1 is a novel tumor suppressor-like molecule we identified through its ability to interact with and inhibit the oncogenic activity of the Myc oncoprotein, which is widely deregulated in breast cancer...

  3. Functional Analysis of Chromosome 18 in Pancreatic Cancer: Strong Evidence for New Tumour Suppressor Genes

    Directory of Open Access Journals (Sweden)

    Liviu P. Lefter

    2004-04-01

    Conclusion: These data represent strong functional evidence that chromosome 18q encodes strong tumour and metastasis suppressor activity that is able to switch human pancreatic cancer cells to a dormant phenotype.

  4. Structure of the Tetrameric p53 Tumor Suppressor Bound to DNA

    National Research Council Canada - National Science Library

    Marmorstein, Ronen

    2002-01-01

    The p53 tumor suppressor binds DNA as a tetramer to regulate the transcription of genes involved in cell cycle arrest and apoptosis, and alterations in the DNA-binding core domain of p53 are the most...

  5. Regulation of IAP (Inhibitor of Apoptosis) Gene Expression by the p53 Tumor Suppressor Protein

    National Research Council Canada - National Science Library

    Murphy, Maureen

    2003-01-01

    The goal of the work proposed in this application, which has just completed Year 1, was to analyze the ability of the p53 tumor suppressor protein to repress the anti-apoptotic genes survivin and cIAP-2...

  6. Potential of lactic acid bacteria as suppressors of wine allergies

    Directory of Open Access Journals (Sweden)

    Yıldırım Hatice Kalkan

    2017-01-01

    Full Text Available Allergens causes some symptoms as all asthma, allergic conjunctivitis, and allergic rhinitis. These symptoms are seen twice as many in women than in men. The major wine allergens reported in wines are endochitinase 4A and lipid-transfer protein (LTP. This review deal with possibilities of using lactic acid bacteria as suppressors of wine allergies. Phenolic compounds present in wines have not only antioxidant properties causing radical scavenging but also some special properties reported in many in vitro studies as regulating functions in inflammatory cells as mast cells. So what is the role of lactic acid bacteria in these cases? Lactic acid bacteria are used during malolactic fermentation step of wine production with purpose of malic acid reduction. During this bioconversion complex phenolic compounds could be hydrolysed by bacterial enzymes to their aglycone forms. Obtained aglycons could pass through the intestinal epithelium of human and allowed reduction of IgE antibody production by affecting Th1/ Th2 ratio. Considering different contents and quantities of phenols in different grape varieties and consequently in different wines more studies are required in order to determine which lactic acid bacteria and strains could be effective in suppressing wine allergens.

  7. Functional involvement of human discs large tumor suppressor in cytokinesis

    International Nuclear Information System (INIS)

    Unno, Kenji; Hanada, Toshihiko; Chishti, Athar H.

    2008-01-01

    Cytokinesis is the final step of cell division that completes the separation of two daughter cells. We found that the human discs large (hDlg) tumor suppressor homologue is functionally involved in cytokinesis. The guanylate kinase (GUK) domain of hDlg mediates the localization of hDlg to the midbody during cytokinesis, and over-expression of the GUK domain in U2OS and HeLa cells impaired cytokinesis. Mouse embryonic fibroblasts (MEFs) derived from dlg mutant mice contained an increased number of multinucleated cells and showed reduced proliferation in culture. A kinesin-like motor protein, GAKIN, which binds directly to the GUK domain of hDlg, exhibited a similar intracellular distribution pattern with hDlg throughout mitosis and localized to the midbody during cytokinesis. However, the targeting of hDlg and GAKIN to the midbody appeared to be independent of each other. The midbody localization of GAKIN required its functional kinesin-motor domain. Treatment of cells with the siRNA specific for hDlg and GAKIN caused formation of multinucleated cells and delayed cytokinesis. Together, these results suggest that hDlg and GAKIN play functional roles in the maintenance of midbody architecture during cytokinesis

  8. Methylation of Tumor Suppressor Genes in Autoimmune Pancreatitis.

    Science.gov (United States)

    Kinugawa, Yasuhiro; Uehara, Takeshi; Sano, Kenji; Matsuda, Kazuyuki; Maruyama, Yasuhiro; Kobayashi, Yukihiro; Nakajima, Tomoyuki; Hamano, Hideaki; Kawa, Shigeyuki; Higuchi, Kayoko; Hosaka, Noriko; Shiozawa, Satoshi; Ishigame, Hiroki; Ota, Hiroyoshi

    Autoimmune pancreatitis (AIP) is a representative IgG4-related and inflammatory disease of unknown etiology. To clarify mechanisms of carcinogenesis resulting from AIP, we focused on methylation abnormalities and KRAS mutations in AIP. Six tumor suppressor genes (NPTX2, Cyclin D2, FOXE1, TFPI2, ppENK, and p16) that exhibited hypermethylation in pancreatic carcinoma were selected for quantitative SYBR green methylation-specific polymerase chain reaction in 10 AIP specimens, 10 pancreatic adenocarcinoma cases without history of AIP containing carcinoma areas (CAs) and noncarcinoma areas (NCAs), and 11 normal pancreas (NP) samples. KRAS mutation in codons 12, 13, and 61 were also investigated using direct sequencing. Hypermethylation events (≥10%) were identified in NPTX2, Cyclin D2, FOXE1, TFPI2, ppENK, and p16 in 1, 2, 2, 0, 2, and 0 CA cases, respectively, but not in these 6 candidate genes in AIP, NCA, and NP. However, the TFPI2 methylation ratio was significantly higher in AIP than NCA and NP. Direct sequencing results for KRAS showed no single-point mutations in AIP. These are the first studies characterizing methylation abnormalities in AIP. AIP's inflammatory condition may be related to carcinogenesis. Further study will elucidate methylation abnormalities associated with carcinogenesis in AIP.

  9. RASSF6; the Putative Tumor Suppressor of the RASSF Family

    Directory of Open Access Journals (Sweden)

    Hiroaki Iwasa

    2015-12-01

    Full Text Available Humans have 10 genes that belong to the Ras association (RA domain family (RASSF. Among them, RASSF7 to RASSF10 have the RA domain in the N-terminal region and are called the N-RASSF proteins. In contradistinction to them, RASSF1 to RASSF6 are referred to as the C-RASSF proteins. The C-RASSF proteins have the RA domain in the middle region and the Salvador/RASSF/Hippo domain in the C-terminal region. RASSF6 additionally harbors the PSD-95/Discs large/ZO-1 (PDZ-binding motif. Expression of RASSF6 is epigenetically suppressed in human cancers and is generally regarded as a tumor suppressor. RASSF6 induces caspase-dependent and -independent apoptosis. RASSF6 interacts with mammalian Ste20-like kinases (homologs of Drosophila Hippo and cross-talks with the Hippo pathway. RASSF6 binds MDM2 and regulates p53 expression. The interactions with Ras and Modulator of apoptosis 1 (MOAP1 are also suggested by heterologous protein-protein interaction experiments. RASSF6 regulates apoptosis and cell cycle through these protein-protein interactions, and is implicated in the NF-κB and JNK signaling pathways. We summarize our current knowledge about RASSF6 and discuss what common and different properties RASSF6 and the other C-RASSF proteins have.

  10. Epigenetic silencing of tumor suppressor genes: Paradigms, puzzles, and potential.

    Science.gov (United States)

    Kazanets, Anna; Shorstova, Tatiana; Hilmi, Khalid; Marques, Maud; Witcher, Michael

    2016-04-01

    Cancer constitutes a set of diseases with heterogeneous molecular pathologies. However, there are a number of universal aberrations common to all cancers, one of these being the epigenetic silencing of tumor suppressor genes (TSGs). The silencing of TSGs is thought to be an early, driving event in the oncogenic process. With this in consideration, great efforts have been made to develop small molecules aimed at the restoration of TSGs in order to limit tumor cell proliferation and survival. However, the molecular forces that drive the broad epigenetic reprogramming and transcriptional repression of these genes remain ill-defined. Undoubtedly, understanding the molecular underpinnings of transcriptionally silenced TSGs will aid us in our ability to reactivate these key anti-cancer targets. Here, we describe what we consider to be the five most logical molecular mechanisms that may account for this widely observed phenomenon: 1) ablation of transcription factor binding, 2) overexpression of DNA methyltransferases, 3) disruption of CTCF binding, 4) elevation of EZH2 activity, 5) aberrant expression of long non-coding RNAs. The strengths and weaknesses of each proposed mechanism is highlighted, followed by an overview of clinical efforts to target these processes. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  11. RASSF6; the Putative Tumor Suppressor of the RASSF Family.

    Science.gov (United States)

    Iwasa, Hiroaki; Jiang, Xinliang; Hata, Yutaka

    2015-12-09

    Humans have 10 genes that belong to the Ras association (RA) domain family (RASSF). Among them, RASSF7 to RASSF10 have the RA domain in the N-terminal region and are called the N-RASSF proteins. In contradistinction to them, RASSF1 to RASSF6 are referred to as the C-RASSF proteins. The C-RASSF proteins have the RA domain in the middle region and the Salvador/RASSF/Hippo domain in the C-terminal region. RASSF6 additionally harbors the PSD-95/Discs large/ZO-1 (PDZ)-binding motif. Expression of RASSF6 is epigenetically suppressed in human cancers and is generally regarded as a tumor suppressor. RASSF6 induces caspase-dependent and -independent apoptosis. RASSF6 interacts with mammalian Ste20-like kinases (homologs of Drosophila Hippo) and cross-talks with the Hippo pathway. RASSF6 binds MDM2 and regulates p53 expression. The interactions with Ras and Modulator of apoptosis 1 (MOAP1) are also suggested by heterologous protein-protein interaction experiments. RASSF6 regulates apoptosis and cell cycle through these protein-protein interactions, and is implicated in the NF-κB and JNK signaling pathways. We summarize our current knowledge about RASSF6 and discuss what common and different properties RASSF6 and the other C-RASSF proteins have.

  12. Tumor Suppressor Function of CYLD in Nonmelanoma Skin Cancer

    Directory of Open Access Journals (Sweden)

    K. C. Masoumi

    2011-01-01

    Full Text Available Ubiquitin and ubiquitin-related proteins posttranslationally modify substrates, and thereby alter the functions of their targets. The ubiquitination process is involved in various physiological responses, and dysregulation of components of the ubiquitin system has been linked to many diseases including skin cancer. The ubiquitin pathways activated among skin cancers are highly diverse and may reflect the various characteristics of the cancer type. Basal cell carcinoma and squamous cell carcinoma, the most common types of human skin cancer, are instances where the involvement of the deubiquitination enzyme CYLD has been recently highlighted. In basal cell carcinoma, the tumor suppressor protein CYLD is repressed at the transcriptional levels through hedgehog signaling pathway. Downregulation of CYLD in basal cell carcinoma was also shown to interfere with TrkC expression and signaling, thereby promoting cancer progression. By contrast, the level of CYLD is unchanged in squamous cell carcinoma, instead, catalytic inactivation of CYLD in the skin has been linked to the development of squamous cell carcinoma. This paper will focus on the current knowledge that links CYLD to nonmelanoma skin cancers and will explore recent insights regarding CYLD regulation of NF-κB and hedgehog signaling during the development and progression of these types of human tumors.

  13. Regulation of the tumor suppressor PTEN by natural anticancer compounds.

    Science.gov (United States)

    Kim, Do-Hee; Suh, Jinyoung; Surh, Young-Joon; Na, Hye-Kyung

    2017-08-01

    The tumor suppressor phosphatase and tensin homologue (PTEN) has phosphatase activity, with phosphatidylinositol (3,4,5)-trisphosphate (PIP3), a product of phosphatidylinositol 3-kinase (PI3K), as one of the principal substrates. PTEN is a negative regulator of the Akt pathway, which plays a fundamental role in controlling cell growth, survival, and proliferation. Loss of PTEN function has been observed in many different types of cancer. Functional inactivation of PTEN as a consequence of germ-line mutations or promoter hypermethylation predisposes individuals to malignancies. PTEN undergoes posttranslational modifications, such as oxidation, acetylation, phosphorylation, SUMOylation, and ubiquitination, which influence its catalytic activity, interactions with other proteins, and subcellular localization. Cellular redox status is crucial for posttranslational modification of PTEN and its functional consequences. Oxidative stress and inflammation are major causes of loss of PTEN function. Pharmacologic or nutritional restoration of PTEN function is considered a reliable strategy in the management of PTEN-defective cancer. In this review, we highlight natural compounds, such as curcumin, indol-3 carbinol, and omega-3 fatty acids, that have the potential to restore or potentiate PTEN expression/activity, thereby suppressing cancer cell proliferation, survival, and resistance to chemotherapeutic agents. © 2017 New York Academy of Sciences.

  14. ARS2 is a general suppressor of pervasive transcription.

    Science.gov (United States)

    Iasillo, Claudia; Schmid, Manfred; Yahia, Yousra; Maqbool, Muhammad A; Descostes, Nicolas; Karadoulama, Evdoxia; Bertrand, Edouard; Andrau, Jean-Christophe; Jensen, Torben Heick

    2017-09-29

    Termination of transcription is important for establishing gene punctuation marks. It is also critical for suppressing many of the pervasive transcription events occurring throughout eukaryotic genomes and coupling their RNA products to efficient decay. In human cells, the ARS2 protein has been implicated in such function as its depletion causes transcriptional read-through of selected gene terminators and because it physically interacts with the ribonucleolytic nuclear RNA exosome. Here, we study the role of ARS2 on transcription and RNA metabolism genome wide. We show that ARS2 depletion negatively impacts levels of promoter-proximal RNA polymerase II at protein-coding (pc) genes. Moreover, our results reveal a general role of ARS2 in transcription termination-coupled RNA turnover at short transcription units like snRNA-, replication-dependent histone-, promoter upstream transcript- and enhancer RNA-loci. Depletion of the ARS2 interaction partner ZC3H18 mimics the ARS2 depletion, although to a milder extent, whereas depletion of the exosome core subunit RRP40 only impacts RNA abundance post-transcriptionally. Interestingly, ARS2 is also involved in transcription termination events within first introns of pc genes. Our work therefore establishes ARS2 as a general suppressor of pervasive transcription with the potential to regulate pc gene expression. © The Author(s) 2017. Published by Oxford University Press on behalf of Nucleic Acids Research.

  15. RhoB: Team Oncogene or Team Tumor Suppressor?

    Directory of Open Access Journals (Sweden)

    Julia A. Ju

    2018-01-01

    Full Text Available Although Rho GTPases RhoA, RhoB, and RhoC share more than 85% amino acid sequence identity, they play very distinct roles in tumor progression. RhoA and RhoC have been suggested in many studies to contribute positively to tumor development, but the role of RhoB in cancer remains elusive. RhoB contains a unique C-terminal region that undergoes specific post-translational modifications affecting its localization and function. In contrast to RhoA and RhoC, RhoB not only localizes at the plasma membrane, but also on endosomes, multivesicular bodies and has even been identified in the nucleus. These unique features are what contribute to the diversity and potentially opposing functions of RhoB in the tumor microenvironment. Here, we discuss the dualistic role that RhoB plays as both an oncogene and tumor suppressor in the context of cancer development and progression.

  16. Epigenetic regulation of putative tumor suppressor TGFBI in human leukemias.

    Science.gov (United States)

    Fang, Hongbo; Liu, Jing; Guo, Dan; Liu, Peixiang; Zhao, Yongliang

    2014-01-01

    Both in vitro and in vivo data have demonstrated the TGFBI gene functions as a putative tumor suppressor and is frequently downregulated in human tumors of different histological types. The hypermethylation of the TGFBI promoter, as one of the main regulatory mechanisms, is associated with TGFBI silencing. In this study, we used a methylation-specific PCR (MSP) method to evaluate the methylation status of the TGFBI promoter in human leukemias. Real-time RT-PCR and methylation-specific PCR approaches were performed to define the TGFBI expression and promoter methylation in human leukemia cell lines and clinical samples. Genomic DNA was isolated from peripheral blood mononuclear cells from leukemia patients, bisulfite-converted, and analyzed by the MSP method. Hypermethylation of the TGFBI promoter occurred in leukemia cell lines and demethylation treatment reexpressed TGFBI at a substantially increased level in most of leukemia cell lines tested. Furthermore, a much higher level of CpG island methylation and a significantly lower TGFBI expression were also identified in clinical leukemia samples. The results suggest an important role of promoter methylation in regulating TGFBI expression in leukemia, which provides a useful diagnostic marker for clinical management of human leukemias.

  17. Myeloid-Derived Suppressor Cells and Therapeutic Strategies in Cancer

    Directory of Open Access Journals (Sweden)

    Hiroshi Katoh

    2015-01-01

    Full Text Available Development of solid cancer depends on escape from host immunosurveillance. Various types of immune cells contribute to tumor-induced immune suppression, including tumor associated macrophages, regulatory T cells, type 2 NKT cells, and myeloid-derived suppressor cells (MDSCs. Growing body of evidences shows that MDSCs play pivotal roles among these immunosuppressive cells in multiple steps of cancer progression. MDSCs are immature myeloid cells that arise from myeloid progenitor cells and comprise a heterogeneous immune cell population. MDSCs are characterized by the ability to suppress both adaptive and innate immunities mainly through direct inhibition of the cytotoxic functions of T cells and NK cells. In clinical settings, the number of circulating MDSCs is associated with clinical stages and response to treatment in several cancers. Moreover, MDSCs are reported to contribute to chemoresistant phenotype. Collectively, targeting MDSCs could potentially provide a rationale for novel treatment strategies in cancer. This review summarizes recent understandings of MDSCs in cancer and discusses promissing clinical approaches in cancer patients.

  18. Drafting the proteome landscape of myeloid-derived suppressor cells.

    Science.gov (United States)

    Gato, María; Blanco-Luquin, Idoia; Zudaire, Maribel; de Morentin, Xabier Martínez; Perez-Valderrama, Estela; Zabaleta, Aintzane; Kochan, Grazyna; Escors, David; Fernandez-Irigoyen, Joaquín; Santamaría, Enrique

    2016-01-01

    Myeloid-derived suppressor cells (MDSCs) are a heterogeneous population of cells that are defined by their myeloid origin, immature state, and ability to potently suppress T-cell responses. They regulate immune responses and the population significantly increases in the tumor microenvironment of patients with glioma and other malignant tumors. For their study, MDSCs are usually isolated from the spleen or directly of tumors from a large number of tumor-bearing mice although promising ex vivo differentiated MDSC production systems have been recently developed. During the last years, proteomics has emerged as a powerful approach to analyze MDSCs proteomes using shotgun-based mass spectrometry (MS), providing functional information about cellular homeostasis and metabolic state at a global level. Here, we will revise recent proteome profiling studies performed in MDSCs from different origins. Moreover, we will perform an integrative functional analysis of the protein compilation derived from these large-scale proteomic studies in order to obtain a comprehensive view of MDSCs biology. Finally, we will also discuss the potential application of high-throughput proteomic approaches to study global proteome dynamics and post-translational modifications (PTMs) during the differentiation process of MDSCs that will greatly boost the identification of novel MDSC-specific therapeutic targets to apply in cancer immunotherapy. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. SIRT3: Oncogene and Tumor Suppressor in Cancer

    Directory of Open Access Journals (Sweden)

    Margalida Torrens-Mas

    2017-07-01

    Full Text Available Sirtuin 3 (SIRT3, the major deacetylase in mitochondria, plays a crucial role in modulating oxygen reactive species (ROS and limiting the oxidative damage in cellular components. SIRT3 targets different enzymes which regulate mitochondrial metabolism and participate in ROS detoxification, such as the complexes of the respiratory chain, the isocitrate dehydrogenase, or the manganese superoxide dismutase. Thus, SIRT3 activity is essential in maintaining mitochondria homeostasis and has recently received great attention, as it is considered a fidelity protein for mitochondrial function. In some types of cancer, SIRT3 functions as a tumoral promoter, since it keeps ROS levels under a certain threshold compatible with cell viability and proliferation. On the contrary, other studies describe SIRT3 as a tumoral suppressor, as SIRT3 could trigger cell death under stress conditions. Thus, SIRT3 could have a dual role in cancer. In this regard, modulation of SIRT3 activity could be a new target to develop more personalized therapies against cancer.

  20. Tropomyosin-1, A Putative Tumor-Suppressor and a Biomarker of Human Breast Cancer

    Science.gov (United States)

    2004-10-01

    cDNA. Lobular carcinoma - 2 A polyclonal pan-TM antibody that recognizes multiple TM Phyllodes tumor - 1 Not determined from the initial pathology...AD Award Number: DAMD17-98-1-8162 TITLE: Tropomyosin-1, A Putative Tumor -Suppressor and a Biomarker of Human Breast Cancer PRINCIPAL INVESTIGATOR...4. TITLE AND SUBTITLE 5. FUNDING NUMBERS Tropomyosin-l, A Putative Tumor -Suppressor and a Biomarker DAMD17-98-1-8162 of Human Breast Cancer 6. A UTHOR

  1. Is efficiency of suppressor tRNAs controlled at the level of ribosomal proofreading in vivo?

    OpenAIRE

    Faxén, M; Kirsebom, L A; Isaksson, L A

    1988-01-01

    Ribosomal rpsD mutations did not stimulate nonsense suppressor tRNAs in a general manner according to their increased ribosomal ambiguity and decreased proofreading efficiency. Streptomycin, which stimulates error production by blocking proofreading in vitro, did not increase efficiency of suppressor tRNAs in strains with normal or streptomycin-resistant (rpsL) ribosomes. It did so only in combination with one rpsL mutation which is associated with streptomycin pseudodependence.

  2. Regulatory role for the memory B cell as suppressor-inducer of feedback control

    International Nuclear Information System (INIS)

    Kennedy, M.W.; Thomas, D.B.

    1983-01-01

    A regulatory role is proposed for the antigen-responsive B cell, as suppressor-inducer of feedback control during the secondary response in vivo. In a double adoptive transfer of memory cells primed to a thymus-dependent antigen from one irradiated host to another, antigen-specific suppressors are generated after a critical time in the primary recipient, able to entirely ablate a secondary anti-hapten response. Positive cell selection in the fluorescence-activated cell sorter confirmed that suppression was mediated by an Lyt-2+ T cell; however, positively selected B cells were also inhibitory and able to induce suppressors in a carrier-specific manner: B hapten induced suppressors in a carrier-primed population, and B carrier induced suppressors in a hapten-carrier population. At the peak of the antibody response in the primary host, memory B cells and their progeny were unable to differentiate further to plasma cells due to their intrinsic suppressor-inducer activity, but this autoregulatory circuit could be severed by adoptive transfer to carrier-primed, X-irradiated recipients

  3. Improved cognitive flexibility in serotonin transporter knockout rats is unchanged following chronic cocaine self-administration

    NARCIS (Netherlands)

    Nonkes, L.J.; Maes, J.H.R.; Homberg, J.R.

    2013-01-01

    Cocaine dependence is associated with orbitofrontal cortex (OFC)-dependent cognitive inflexibility in both humans and laboratory animals. A critical question is whether cocaine self-administration affects pre-existing individual differences in cognitive flexibility. Serotonin transporter knockout

  4. Serotonin transporter knockout rats show improved strategy set-shifting and reduced latent inhibition

    NARCIS (Netherlands)

    Nonkes, L.J.P.; Vondervoort, I.I.G.M. van de; Leeuw, M.J.C. de; Wijlaars, L.P.; Maes, J.H.R.; Homberg, J.R.

    2012-01-01

    Behavioral flexibility is a cognitive process depending on prefrontal areas allowing adaptive responses to environmental changes. Serotonin transporter knockout (5-HTT−/−) rodents show improved reversal learning in addition to orbitofrontal cortex changes. Another form of behavioral flexibility,

  5. Serotonin transporter knockout rats show improved strategy set-shifting and reduced latent inhibition.

    NARCIS (Netherlands)

    Nonkes, L.J.P.; Vondervoort, I.I. van de; Leeuw, M.J. de; Wijlaars, L.P.; Maes, J.H.; Homberg, J.R.

    2012-01-01

    Behavioral flexibility is a cognitive process depending on prefrontal areas allowing adaptive responses to environmental changes. Serotonin transporter knockout (5-HTT(-/-)) rodents show improved reversal learning in addition to orbitofrontal cortex changes. Another form of behavioral flexibility,

  6. A novel CBL-Bflox/flox mouse model allows tissue-selective fully conditional CBL/CBL-B double-knockout: CD4-Cre mediated CBL/CBL-B deletion occurs in both T-cells and hematopoietic stem cells.

    Science.gov (United States)

    Goetz, Benjamin; An, Wei; Mohapatra, Bhopal; Zutshi, Neha; Iseka, Fany; Storck, Matthew D; Meza, Jane; Sheinin, Yuri; Band, Vimla; Band, Hamid

    2016-08-09

    CBL-family ubiquitin ligases are critical negative regulators of tyrosine kinase signaling, with a clear redundancy between CBL and CBL-B evident in the immune cell and hematopoietic stem cell studies. Since CBL and CBL-B are negative regulators of immune cell activation, elimination of their function to boost immune cell activities could be beneficial in tumor immunotherapy. However, mutations of CBL are associated with human leukemias, pointing to tumor suppressor roles of CBL proteins; hence, it is critical to assess the tumor-intrinsic roles of CBL and CBL-B in cancers. This has not been possible since the only available whole-body CBL-B knockout mice exhibit constitutive tumor rejection. We engineered a new CBL-Bflox/flox mouse, combined this with an existing CBLflox/flox mouse to generate CBLflox/flox; CBL-Bflox/flox mice, and tested the tissue-specific concurrent deletion of CBL and CBL-B using the widely-used CD4-Cre transgenic allele to produce a T-cell-specific double knockout. Altered T-cell development, constitutive peripheral T-cell activation, and a lethal multi-organ immune infiltration phenotype largely resembling the previous Lck-Cre driven floxed-CBL deletion on a CBL-B knockout background establish the usefulness of the new model for tissue-specific CBL/CBL-B deletion. Unexpectedly, CD4-Cre-induced deletion in a small fraction of hematopoietic stem cells led to expansion of certain non-T-cell lineages, suggesting caution in the use of CD4-Cre for T-cell-restricted gene deletion. The establishment of a new model of concurrent tissue-selective CBL/CBL-B deletion should allow a clear assessment of the tumor-intrinsic roles of CBL/CBL-B in non-myeloid malignancies and help test the potential for CBL/CBL-B inactivation in immunotherapy of tumors.

  7. Altered Sleep Homeostasis in Rev-erbα Knockout Mice.

    Science.gov (United States)

    Mang, Géraldine M; La Spada, Francesco; Emmenegger, Yann; Chappuis, Sylvie; Ripperger, Jürgen A; Albrecht, Urs; Franken, Paul

    2016-03-01

    The nuclear receptor REV-ERBα is a potent, constitutive transcriptional repressor critical for the regulation of key circadian and metabolic genes. Recently, REV-ERBα's involvement in learning, neurogenesis, mood, and dopamine turnover was demonstrated suggesting a specific role in central nervous system functioning. We have previously shown that the brain expression of several core clock genes, including Rev-erbα, is modulated by sleep loss. We here test the consequences of a loss of REV-ERBα on the homeostatic regulation of sleep. EEG/EMG signals were recorded in Rev-erbα knockout (KO) mice and their wild type (WT) littermates during baseline, sleep deprivation, and recovery. Cortical gene expression measurements after sleep deprivation were contrasted to baseline. Although baseline sleep/wake duration was remarkably similar, KO mice showed an advance of the sleep/wake distribution relative to the light-dark cycle. After sleep onset in baseline and after sleep deprivation, both EEG delta power (1-4 Hz) and sleep consolidation were reduced in KO mice indicating a slower increase of homeostatic sleep need during wakefulness. This slower increase might relate to the smaller increase in theta and gamma power observed in the waking EEG prior to sleep onset under both conditions. Indeed, the increased theta activity during wakefulness predicted delta power in subsequent NREM sleep. Lack of Rev-erbα increased Bmal1, Npas2, Clock, and Fabp7 expression, confirming the direct regulation of these genes by REV-ERBα also in the brain. Our results add further proof to the notion that clock genes are involved in sleep homeostasis. Because accumulating evidence directly links REV-ERBα to dopamine signaling the altered homeostatic regulation of sleep reported here are discussed in that context. © 2016 Associated Professional Sleep Societies, LLC.

  8. Piroxicam treatment augments bone abnormalities in interleukin-10 knockout mice.

    Science.gov (United States)

    Holgersen, Kristine; Dobie, Ross; Farquharson, Colin; vanʼt Hof, Rob; Ahmed, Syed Faisal; Hansen, Axel Kornerup; Holm, Thomas L

    2015-02-01

    Osteoporosis and fractures are common complications of inflammatory bowel disease. The pathogenesis is multifactorial and has been partly attributed to intestinal inflammation. The aim of this study was to evaluate bone status and assess the association between bone loss and gut inflammation in an experimental colitis model. Colitis was induced in interleukin-10 knockout mice (PAC IL-10 k.o.) by peroral administration of piroxicam for 12 days. The degree of colitis was assessed by clinical, macroscopic, and microscopic evaluation. Trabecular and cortical bone microarchitecture of tibia were determined using micro-computed tomography. Moreover, the serum levels of bone formation and bone resorption biomarkers were measured, and inflammatory protein profiling was performed on colons. PAC IL-10 k.o. mice developed severe colitis, characterized by hyperplasia and focal transmural inflammation, which was consistent with Crohn's disease-like pathology. The gut inflammation was accompanied by a 14% and 12% reduction in trabecular thickness relative to piroxicam-treated wild type and untreated wild type mice, respectively (P < 0.001). The trabecular bone structure was also changed in PAC IL-10 k.o. mice, whereas no differences in cortical bone geometry were observed. The trabecular thickness was inversely correlated with serum levels of CTX (r = -0.93, P = 0.006). Moreover, numerous inflammatory mediators, including RANKL and osteoprotegerin, were significantly increased in the colon of PAC IL-10 k.o. mice. PAC IL-10 k.o. mice develop bone loss and changed trabecular structure, as a result of increased bone resorption. Thus, the PAC IL-10 k.o. model could be a useful experimental model in preclinical research of inflammatory bowel disease-associated bone loss.

  9. Analysis of microsatellite polymorphism in inbred knockout mice.

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    Baofen Zuo

    Full Text Available Previously, we found that the genotype of 42 out of 198 mouse microsatellite loci, which are distributed among all chromosomes except the Y chromosome, changed from monomorphism to polymorphism (CMP in a genetically modified inbred mouse strain. In this study, we further examined whether CMP also relates to the homologous recombination in gene knockout (KO mouse strains. The same 42 microsatellite loci were analyzed by polymerase chain reaction (PCR in 29 KO inbred mouse strains via short tandem sequence repeat (STR scanning and direct sequence cloning to justify microsatellite polymorphisms. The C57BL/6J and 129 mouse strains, from which these 29 KO mice were derived, were chosen as the background controls. The results indicated that 10 out of 42 (23.8% loci showed CMP in some of these mouse strains. Except for the trinucleotide repeat locus of D3Mit22, which had microsatellite CMP in strain number 9, the core sequences of the remaining 41 loci were dinucleotide repeats, and 9 out of 41 (21.95% showed CMPs among detected mouse strains. However, 11 out of 29 (37.9% KO mice strains were recognized as having CMPs. The popular dinucleotide motifs in CMP were (TG(n (50%, 2/4, followed by (GT(n (27.27%, 3/11 and (CA(n (23.08%, 3/13. The microsatellite CMP in (CT(n and (AG(n repeats were 20% (1/5. According to cloning sequencing results, 6 KO mouse strains showed insertions of nucleotides whereas 1 showed a deletion. Furthermore, 2 loci (D13Mit3 and D14Mit102 revealed CMP in 2 strains, and mouse strain number 9 showed CMPs in two loci (D3Mit22 and D13Mit3 simultaneously. Collectively, these results indicated that microsatellite polymorphisms were present in the examined inbred KO mice.

  10. Osteoprotegerin-Knockout Mice Developed Early Onset Root Resorption.

    Science.gov (United States)

    Liu, Yi; Du, Haiming; Wang, Yunfei; Liu, Mengmeng; Deng, Shijian; Fan, Linlin; Zhang, Lili; Sun, Yao; Zhang, Qi

    2016-10-01

    Recent studies indicate that the osteoprotegerin (OPG)/RANKL/RANK pathway takes part in root resorption. However, the relationship between OPG and root resorption is vague. The purpose of our study was to investigate the role of OPG in root resorption. The first molars of the mandibles of osteoprotegerin-knockout (Opg-KO) mice and wild-type (WT) mice were evaluated by micro-computed tomography, histology, and immunohistochemistry at 4, 6, 26, and 52 weeks. To detect the activity of the osteoclasts, we induced bone marrow macrophages into osteoclast-like cells from Opg-KO mice and wild-type mice in vitro and then compared their osteoclast activities. To evaluate the cementum quality, an osteoclast-cementum co-culture model was established in vitro. In Opg-KO mice, root resorption began at the age of 4 weeks. At 6 weeks the cementum damage extended to the coronal and apical regions, and at 52 weeks the damage reached the predentin. At all observed stages, more tartrate-resistant acid phosphatase (TRAP)-positive cells were found on the surface of cementum in Opg-KO mice. In vitro, the mRNA levels of cathepsin K, TRAP, matrix metalloproteinase-9, and matrix metalloproteinase-1, as well as the protein expression of nuclear factor of activated T cell 1 and TRAP, increased significantly in osteoclast-like cells from Opg-KO mice. In addition, the cementum resorption pits of Opg-KO mice were larger when co-cultured with osteoclast-like cells. Our study demonstrated that loss of OPG led to root resorption via increasing activation of osteoclasts and reducing mineralization of cementum. Copyright © 2016. Published by Elsevier Inc.

  11. Characterization of Heterogeneous Prostate Tumors in Targeted Pten Knockout Mice.

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    Hanneke Korsten

    Full Text Available Previously, we generated a preclinical mouse prostate tumor model based on PSA-Cre driven inactivation of Pten. In this model homogeneous hyperplastic prostates (4-5m developed at older age (>10m into tumors. Here, we describe the molecular and histological characterization of the tumors in order to better understand the processes that are associated with prostate tumorigenesis in this targeted mouse Pten knockout model. The morphologies of the tumors that developed were very heterogeneous. Different histopathological growth patterns could be identified, including intraductal carcinoma (IDC, adenocarcinoma and undifferentiated carcinoma, all strongly positive for the epithelial cell marker Cytokeratin (CK, and carcinosarcomas, which were negative for CK. IDC pattern was already detected in prostates of 7-8 month old mice, indicating that it could be a precursor stage. At more than 10 months IDC and carcinosarcoma were most frequently observed. Gene expression profiling discriminated essentially two molecular subtypes, denoted tumor class 1 (TC1 and tumor class 2 (TC2. TC1 tumors were characterized by high expression of epithelial markers like Cytokeratin 8 and E-Cadherin whereas TC2 tumors showed high expression of mesenchyme/stroma markers such as Snail and Fibronectin. These molecular subtypes corresponded with histological growth patterns: where TC1 tumors mainly represented adenocarcinoma/intraductal carcinoma, in TC2 tumors carcinosarcoma was the dominant growth pattern. Further molecular characterization of the prostate tumors revealed an increased expression of genes associated with the inflammatory response. Moreover, functional markers for senescence, proliferation, angiogenesis and apoptosis were higher expressed in tumors compared to hyperplasia. The highest expression of proliferation and angiogenesis markers was detected in TC2 tumors. Our data clearly showed that in the genetically well-defined PSA-Cre;Pten-loxP/loxP prostate tumor

  12. Maximal Oxygen Consumption is Reduced in Aquaporin-1 Knockout Mice

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    Samer Al-Samir

    2016-08-01

    Full Text Available We have measured maximal oxygen consumption (V’O2,max of mice lacking one or two of the established mouse red-cell CO2 channels AQP1, AQP9 and Rhag. We intended to study whether these proteins, by acting as channels for O2, determine O2 exchange in the lung and in the periphery. We found that V’O2,max as determined by the Helox technique is reduced by ~ 16%, when AQP1 is knocked out, but not when AQP9 or Rhag are lacking. This figure holds for animals respiring normoxic as well as hypoxic gas mixtures. To see whether the reduction of V’O2,max is due to impaired O2 uptake in the lung, we measured carotid arterial O2 saturation (SO2 by pulse oximetry. Neither under normoxic (inspiratory O2 21% nor under hypoxic conditions (11% O2 is there a difference in SO2 between AQP1null and WT mice, suggesting that AQP1 is not critical for O2 uptake in the lung. The fact that the % reduction of V’O2,max is identical in normoxia and hypoxia indicates moreover that the limitation of V’O2,max is not due to an O2 diffusion problem, neither in the lung nor in the periphery. Instead, it appears likely that AQP1null animals exhibit a reduced V’O2,max due to the reduced wall thickness and muscle mass of the left ventricles of their hearts, as reported previously. We conclude that very likely the properties of the hearts of AQP1 knockout mice cause a reduced maximal cardiac output and thus cause a reduced V’O2,max, which constitutes a new phenotype of these mice.

  13. Elevated body temperature during sleep in orexin knockout mice

    Science.gov (United States)

    Mochizuki, Takatoshi; Klerman, Elizabeth B.; Sakurai, Takeshi; Scammell, Thomas E.

    2008-01-01

    Core body temperature (Tb) is influenced by many physiological factors, including behavioral state, locomotor activity, and biological rhythms. To determine the relative roles of these factors, we examined Tb in orexin knockout (KO) mice, which have a narcolepsy-like phenotype with severe sleep-wake fragmentation. Because orexin is thought to promote heat production during wakefulness, we hypothesized that orexin KO mice would have lower Tb while awake. Surprisingly, the Tb of orexin KO mice was 0.4°C higher than wild-type (WT) littermates during the dark period. Orexin KO mice had normal diurnal variations in Tb, but the ultradian rhythms of Tb, locomotor activity, and wakefulness were markedly reduced. During sustained wakefulness, Tb was the same in both groups. During the first 15 min of spontaneous sleep, the Tb of WT mice decreased by 1.0°C, but Tb in orexin KO mice decreased only 0.4°C. Even during intense recovery sleep after 8 hr of sleep deprivation, the Tb of orexin KO mice remained 0.7°C higher than in WT mice. This blunted fall in Tb during sleep may be due to inadequate activation of heat loss mechanisms or sustained activity in heat-generating systems. These observations reveal an unexpected role for orexin in thermoregulation. In addition, because heat loss is an essential aspect of sleep, the blunted fall in Tb of orexin KO mice may provide an explanation for the fragmented sleep of narcolepsy. PMID:16556901

  14. Salty taste deficits in CALHM1 knockout mice.

    Science.gov (United States)

    Tordoff, Michael G; Ellis, Hillary T; Aleman, Tiffany R; Downing, Arnelle; Marambaud, Philippe; Foskett, J Kevin; Dana, Rachel M; McCaughey, Stuart A

    2014-07-01

    Genetic ablation of calcium homeostasis modulator 1 (CALHM1), which releases adenosine triphosphate from Type 2 taste cells, severely compromises the behavioral and electrophysiological responses to tastes detected by G protein-coupled receptors, such as sweet and bitter. However, the contribution of CALHM1 to salty taste perception is less clear. Here, we evaluated several salty taste-related phenotypes of CALHM1 knockout (KO) mice and their wild-type (WT) controls: 1) In a conditioned aversion test, CALHM1 WT and KO mice had similar NaCl avoidance thresholds. 2) In two-bottle choice tests, CALHM1 WT mice showed the classic inverted U-shaped NaCl concentration-preference function but CALHM1 KO mice had a blunted peak response. 3) In brief-access tests, CALHM1 KO mice showed less avoidance than did WT mice of high concentrations of NaCl, KCl, NH(4)Cl, and sodium lactate (NaLac). Amiloride further ameliorated the NaCl avoidance of CALHM1 KO mice, so that lick rates to a mixture of 1000 mM NaCl + 10 µM amiloride were statistically indistinguishable from those to water. 4) Relative to WT mice, CALHM1 KO mice had reduced chorda tympani nerve activity elicited by oral application of NaCl, NaLac, and sucrose but normal responses to HCl and NH(4)Cl. Chorda tympani responses to NaCl and NaLac were amiloride sensitive in WT but not KO mice. These results reinforce others demonstrating that multiple transduction pathways make complex, concentration-dependent contributions to salty taste perception. One of these pathways depends on CALHM1 to detect hypertonic NaCl in the mouth and signal the aversive taste of concentrated salt. © The Author 2014. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  15. Myeloid-derived suppressor cells in murine AIDS inhibit B-cell responses in part via soluble mediators including reactive oxygen and nitrogen species, and TGF-β.

    Science.gov (United States)

    Rastad, Jessica L; Green, William R

    2016-12-01

    Monocytic myeloid-derived suppressor cells (M-MDSCs) were increased during LP-BM5 retroviral infection, and were capable of suppressing not only T-cell, but also B-cell responses. In addition to previously demonstrating iNOS- and VISTA-dependent M-MDSC mechanisms, in this paper, we detail how M-MDSCs utilized soluble mediators, including the reactive oxygen and nitrogen species superoxide, peroxynitrite, and nitric oxide, and TGF-β, to suppress B cells in a predominantly contact-independent manner. Suppression was independent of cysteine-depletion and hydrogen peroxide production. When two major mechanisms of suppression (iNOS and VISTA) were eliminated in double knockout mice, M-MDSCs from LP-BM5-infected mice were able to compensate using other, soluble mechanisms in order to maintain suppression of B cells. The IL-10 producing regulatory B-cell compartment was among the targets of M-MDSC-mediated suppression. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. Soluble suppressor supernatants elaborated by concanavalin A-activated human mononuclear cells. Characterization of a soluble suppressor of B cell immunoglobulin production

    International Nuclear Information System (INIS)

    Fleisher, T.A.; Greene, W.C.; Blaese, R.M.; Waldmann, T.A.

    1981-01-01

    Human peripheral blood mononuclear cells (PBMC) activated with the mitogenic lectin concanavalin A (Con A) elaborate a soluble immune suppressor supernatant (SISS) that contains at least 2 distinct suppressor factors. One of these, SISS-B, inhibits polyclonal B cell immunoglobulin production, whereas the other, SISS-T, suppresses T cell proliferation to both mitogens and antigens. The latter mediator is discussed in the companion paper. Characteristics of the human soluble suppressor of B cell immunoglobulin production (SISS-B) include: 1) inhibition by a noncytotoxic mechanism, 2) loss of activity in the presence of the monosaccharide L-rhamnose, 3) appearance within 8 to 16 hr after the addition of Con A, 4) elaboration by cells irradiated with 500 or 2000 rads, 5) production by highly purified T cells, 6) stability at pH 2.5 but instability at 56/sup o/C, and 7) m.w. of 60 to 80,000. These data indicate that after Con A activation, selected T cells not only become potent suppressor cells, but also generate a soluble saccharide-specific factor(s) that inhibits polyclonal immunoglobulin production by human B cells

  17. Tumor-suppressor activity of RRIG1 in breast cancer

    International Nuclear Information System (INIS)

    Zhang, Guihong; Brewster, Abenaa; Guan, Baoxiang; Fan, Zhen; Brown, Powel H; Xu, Xiao-Chun

    2011-01-01

    Retinoid receptor-induced gene-1 (RRIG1) is a novel gene that has been lost in several types of human cancers. The aim of this study was to determine whether RRIG1 plays a role in breast cancer, such as in the suppression of breast cancer cell growth and invasion. Immunohistochemistry was used to detect RRIG1 expression in breast tissue specimens. Gene transfection was used to restore or knock down RRIG1 expression in breast cancer cell lines for analysis of cell viability, colony formation, and migration/invasion potential. Reverse-transcription polymerase chain reaction and western blot assays were used to detect the changes in gene expression. The RhoA activation assay was used to assess RRIG1-induced inhibition of RhoA activity. The immunohistochemical data showed that RRIG1 expression was reduced in breast cancer tissues compared with normal and atypical hyperplastic breast tissues. RRIG1 expression was inversely correlated with lymph node metastasis of breast cancer but was not associated with the status of hormone receptors, such as estrogen receptor, progesterone receptor, or HER2. Furthermore, restoration of RRIG1 expression inhibited proliferation, colony formation, migration, and invasion of breast cancer cells. Expression of RRIG1 also reduced phosphorylated Erk1/2 and Akt levels; c-Jun, MMP9, and Akt expressions; and RhoA activity. In contrast, knockdown of RRIG1 expression promoted breast cancer cell proliferation, colony formation, migration, and invasion potential. The data from the current study indicated that RRIG1 expression was reduced or lost in breast cancer and that restoration of RRIG1 expression suppressed breast cancer cell growth and invasion capacity. Future studies will determine the underlying molecular mechanisms and define RRIG1 as a tumor-suppressor gene in breast cancer

  18. Latexin exhibits tumor-suppressor potential in pancreatic ductal adenocarcinoma

    Science.gov (United States)

    XUE, ZHANXIONG; ZHOU, YUHUI; WANG, CHENG; ZHENG, JIHANG; ZHANG, PU; ZHOU, LINGLING; WU, LIANG; SHAN, YUNFENG; YE, MENGSI; HE, YUN; CAI, ZHENZHAI

    2016-01-01

    Recent studies suggest that latexin (Lxn) expression is involved in stem cell regulation and that it plays significant roles in tumor cell migration and invasion. The clinicopathological significance of Lxn expression and its possible correlation with CD133 expression in pancreatic ductal adenocarcinoma (PDAC) is currently unknown. In the present study, immunohistochemical analysis was performed to determine Lxn and CD133 expression in 43 PDAC patient samples and in 32 corresponding adjacent non-cancerous samples. The results were analyzed and compared with patient age, gender, tumor site and size, histological grade, clinical stage and overall mean survival time. Lxn expression was clearly decreased in the PDAC tissues compared with that in the adjacent non-cancerous tissues, while CD133 expression was increased. Low Lxn expression in the PDAC tissues was significantly correlated with tumor size (P=0.002), histological grade (P=0.000), metastasis (P=0.007) and clinical stage (P=0.018), but not with age (P=0.451), gender (P=0.395) or tumor site (P=0.697). Kaplan-Meier survival analysis revealed that low Lxn expression was significantly correlated with reduced overall survival time (P=0.000). Furthermore, Lxn expression was found to be inversely correlated with CD133 expression (r=−0.485, P=0.001). Furthermore, CD133-positive MIA PaCa-2 pancreatic tumor cells were sorted by magnetic-activated cell sorting (MACS), and those that overexpressed Lxn exhibited a significantly higher rate of apoptosis and lower proliferative activity. Our findings suggest that Lxn may function as a tumor suppressor that targets CD133-positive pancreatic cancer cells. PMID:26530530

  19. The Retinoblastoma Tumor Suppressor Regulates a Xenobiotic Detoxification Pathway

    Science.gov (United States)

    Sáenz Robles, Maria Teresa; Case, Ashley; Chong, Jean-Leon; Leone, Gustavo; Pipas, James M.

    2011-01-01

    The retinoblastoma tumor suppressor (pRb) regulates cell cycle entry, progression and exit by controlling the activity of the E2F-family of transcription factors. During cell cycle exit pRb acts as a transcriptional repressor by associating with E2F proteins and thereby inhibiting their ability to stimulate the expression of genes required for S phase. Indeed, many tumors harbor mutations in the RB gene and the pRb-E2F pathway is compromised in nearly all types of cancers. In this report we show that both pRb and its interacting partners, the transcriptional factors E2F1-2-3, act as positive modulators of detoxification pathways important for metabolizing and clearing xenobiotics—such as toxins and drugs—from the body. Using a combination of conventional molecular biology techniques and microarray analysis of specific cell populations, we have analyzed the detoxification pathway in murine samples in the presence or absence of pRb and/or E2F1-2-3. In this report, we show that both pRb and E2F1-2-3 act as positive modulators of detoxification pathways in mice, challenging the conventional view of E2F1-2-3 as transcriptional repressors negatively regulated by pRb. These results suggest that mutations altering the pRb-E2F axis may have consequences beyond loss of cell cycle control by altering the ability of tissues to remove toxins and to properly metabolize anticancer drugs, and might help to understand the formation and progression rates of different types of cancer, as well as to better design appropriate therapies based on the particular genetic composition of the tumors. PMID:22022495

  20. Sildenafil restores endothelial function in the apolipoprotein E knockout mouse

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    Balarini Camille M

    2013-01-01

    Full Text Available Abstract Background Atherosclerosis is an inflammatory process of the arterial walls and is initiated by endothelial dysfunction accompanied by an imbalance in the production of reactive oxygen species (ROS and nitric oxide (NO. Sildenafil, a selective phosphodiesterase-5 (PDE5 inhibitor used for erectile dysfunction, exerts its cardiovascular effects by enhancing the effects of NO. The aim of this study was to investigate the influence of sildenafil on endothelial function and atherosclerosis progression in apolipoprotein E knockout (apoE−/− mice. Methods ApoE−/− mice treated with sildenafil (Viagra®, 40 mg/kg/day, for 3 weeks, by oral gavage were compared to the untreated apoE−/− and the wild-type (WT mice. Aortic rings were used to evaluate the relaxation responses to acetylcholine (ACh in all of the groups. In a separate set of experiments, the roles of NO and ROS in the relaxation response to ACh were evaluated by incubating the aortic rings with L-NAME (NO synthase inhibitor or apocynin (NADPH oxidase inhibitor. In addition, the atherosclerotic lesions were quantified and superoxide production was assessed. Results Sildenafil restored the vasodilator response to acetylcholine (ACh in the aortic rings of the apoE−/− mice. Treatment with L-NAME abolished the vasodilator responses to ACh in all three groups of mice and revealed an augmented participation of NO in the endothelium-dependent vasodilation in the sildenafil-treated animals. The normalized endothelial function in sildenafil-treated apoE−/− mice was unaffected by apocynin highlighting the low levels of ROS production in these animals. Moreover, morphological analysis showed that sildenafil treatment caused approximately a 40% decrease in plaque deposition in the aorta. Conclusion This is the first study demonstrating the beneficial effects of chronic treatment with sildenafil on endothelial dysfunction and atherosclerosis in a model of spontaneous

  1. Phenotypic assessment of THC discriminative stimulus properties in fatty acid amide hydrolase knockout and wildtype mice.

    Science.gov (United States)

    Walentiny, D Matthew; Vann, Robert E; Wiley, Jenny L

    2015-06-01

    A number of studies have examined the ability of the endogenous cannabinoid anandamide to elicit Δ(9)-tetrahydrocannabinol (THC)-like subjective effects, as modeled through the THC discrimination paradigm. In the present study, we compared transgenic mice lacking fatty acid amide hydrolase (FAAH), the enzyme primarily responsible for anandamide catabolism, to wildtype counterparts in a THC discrimination procedure. THC (5.6 mg/kg) served as a discriminative stimulus in both genotypes, with similar THC dose-response curves between groups. Anandamide fully substituted for THC in FAAH knockout, but not wildtype, mice. Conversely, the metabolically stable anandamide analog O-1812 fully substituted in both groups, but was more potent in knockouts. The CB1 receptor antagonist rimonabant dose-dependently attenuated THC generalization in both groups and anandamide substitution in FAAH knockouts. Pharmacological inhibition of monoacylglycerol lipase (MAGL), the primary catabolic enzyme for the endocannabinoid 2-arachidonoylglycerol (2-AG), with JZL184 resulted in full substitution for THC in FAAH knockout mice and nearly full substitution in wildtypes. Quantification of brain endocannabinoid levels revealed expected elevations in anandamide in FAAH knockout mice compared to wildtypes and equipotent dose-dependent elevations in 2-AG following JZL184 administration. Dual inhibition of FAAH and MAGL with JZL195 resulted in roughly equipotent increases in THC-appropriate responding in both groups. While the notable similarity in THC's discriminative stimulus effects across genotype suggests that the increased baseline brain anandamide levels (as seen in FAAH knockout mice) do not alter THC's subjective effects, FAAH knockout mice are more sensitive to the THC-like effects of pharmacologically induced increases in anandamide and MAGL inhibition (e.g., JZL184). Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Knockout of endothelial cell-derived endothelin-1 attenuates skin fibrosis but accelerates cutaneous wound healing.

    Science.gov (United States)

    Makino, Katsunari; Jinnin, Masatoshi; Aoi, Jun; Kajihara, Ikko; Makino, Takamitsu; Fukushima, Satoshi; Sakai, Keisuke; Nakayama, Kazuhiko; Emoto, Noriaki; Yanagisawa, Masashi; Ihn, Hironobu

    2014-01-01

    Endothelin (ET)-1 is known for the most potent vasoconstrictive peptide that is released mainly from endothelial cells. Several studies have reported ET-1 signaling is involved in the process of wound healing or fibrosis as well as vasodilation. However, little is known about the role of ET-1 in these processes. To clarify its mechanism, we compared skin fibrogenesis and wound repair between vascular endothelial cell-specific ET-1 knockout mice and their wild-type littermates. Bleomycin-injected fibrotic skin of the knockout mice showed significantly decreased skin thickness and collagen content compared to that of wild-type mice, indicating that bleomycin-induced skin fibrosis is attenuated in the knockout mice. The mRNA levels of transforming growth factor (TGF)-β were decreased in the bleomycin-treated skin of ET-1 knockout mice. On the other hand, skin wound healing was accelerated in ET-1 knockout mice, which was indicated by earlier granulation tissue reduction and re-epithelialization in these mice. The mRNA levels of TGF-β, tumor necrosis factor (TNF)-α and connective tissue growth factor (CTGF) were reduced in the wound of ET-1 knockout mice. In endothelial ET-1 knockout mouse, the expression of TNF-α, CTGF and TGF-β was down-regulated. Bosentan, an antagonist of dual ET receptors, is known to attenuate skin fibrosis and accelerate wound healing in systemic sclerosis, and such contradictory effect may be mediated by above molecules. The endothelial cell-derived ET-1 is the potent therapeutic target in fibrosis or wound healing, and investigations of the overall regulatory mechanisms of these pathological conditions by ET-1 may lead to a new therapeutic approach.

  3. Impaired social behavior in 5-HT3A receptor knockout mice

    Directory of Open Access Journals (Sweden)

    Laura A Smit-Rigter

    2010-11-01

    Full Text Available The 5-HT3 receptor is a ligand-gated ion channel expressed on interneurons throughout the brain. So far, analysis of the 5-HT3A knockout mouse revealed changes in nociceptive processing and a reduction in anxiety related behavior. Recently, it was shown that the 5-HT3 receptor is also expressed on Cajal-Retzius cells which play a key role in cortical development and that knockout mice lacking this receptor showed aberrant growth of the dendritic tree of cortical layer II/III pyramidal neurons. Other mouse models in which serotonergic signaling was disrupted during development showed similar morphological changes in the cortex, and in addition, also deficits in social behavior. Here, we subjected male and female 5-HT3A knockout mice and their non-transgenic littermates to several tests of social behavior. We found that 5-HT3A knockout mice display impaired social communication in the social transmission of food preference task. Interestingly, we showed that in the social interaction test only female 5-HT3A knockout mice spent less time in reciprocal social interaction starting after 5 minutes of testing. Moreover, we observed differences in preference for social novelty for male and female 5-HT3A knockout mice during the social approach test. However, no changes in olfaction, exploratory activity and anxiety were detected. These results indicate that the 5-HT3A knockout mouse displays impaired social behavior with specific changes in males and females, reminiscent to other mouse models in which serotonergic signaling is disturbed in the developing brain.

  4. Knockout of endothelial cell-derived endothelin-1 attenuates skin fibrosis but accelerates cutaneous wound healing.

    Directory of Open Access Journals (Sweden)

    Katsunari Makino

    Full Text Available Endothelin (ET-1 is known for the most potent vasoconstrictive peptide that is released mainly from endothelial cells. Several studies have reported ET-1 signaling is involved in the process of wound healing or fibrosis as well as vasodilation. However, little is known about the role of ET-1 in these processes. To clarify its mechanism, we compared skin fibrogenesis and wound repair between vascular endothelial cell-specific ET-1 knockout mice and their wild-type littermates. Bleomycin-injected fibrotic skin of the knockout mice showed significantly decreased skin thickness and collagen content compared to that of wild-type mice, indicating that bleomycin-induced skin fibrosis is attenuated in the knockout mice. The mRNA levels of transforming growth factor (TGF-β were decreased in the bleomycin-treated skin of ET-1 knockout mice. On the other hand, skin wound healing was accelerated in ET-1 knockout mice, which was indicated by earlier granulation tissue reduction and re-epithelialization in these mice. The mRNA levels of TGF-β, tumor necrosis factor (TNF-α and connective tissue growth factor (CTGF were reduced in the wound of ET-1 knockout mice. In endothelial ET-1 knockout mouse, the expression of TNF-α, CTGF and TGF-β was down-regulated. Bosentan, an antagonist of dual ET receptors, is known to attenuate skin fibrosis and accelerate wound healing in systemic sclerosis, and such contradictory effect may be mediated by above molecules. The endothelial cell-derived ET-1 is the potent therapeutic target in fibrosis or wound healing, and investigations of the overall regulatory mechanisms of these pathological conditions by ET-1 may lead to a new therapeutic approach.

  5. Suppressor cells in transplantation tolerance. III. The role of antigen in the maintenance of transplantation tolerance

    International Nuclear Information System (INIS)

    Tutschka, P.J.; Hess, A.D.; Beschorner, W.E.; Santos, G.W.

    1982-01-01

    Suppressor cells, which in an alloantigen-specific manner inhibit proliferation of donor cells to host antigens in a mixed lymphocyte culture and adoptively transfer the suppression of graft-versus-host disease (GVHD), undergo a gradual clonal reduction in long-term, allogeneic, histoincompatible rat radiation chimeras until they can no longer be measured in an in vitro suppressor cell assay. When lymphohematopoietic cells from these chimeras are transferred into lethally irradiated secondary recipients of original donor strain, the suppressor cells, now in a target antigen-free environment, undergo a further clonal reduction. After parking for 120 days, the chimeric cells are specifically tolerant to original host antigens, but cannot adoptively transfer suppression of GVHD. When chimeric cells, parked for 120 days in secondary recipients of original donor strain, are stimulated with original host-type antigen repeatedly during or once at the end of the parking period, the suppressor cell clone is expanded, suppressor cells can be identified in vitro, and suppression of GVHD can adoptively be transferred to tertiary recipients

  6. Power consumption in positive ion beam converter with electrostatic electron suppressor

    International Nuclear Information System (INIS)

    Hashimoto, Kiyoshi; Sugawara, Tohru

    1985-01-01

    The power recovery characteristics of an in-line direct beam converter provided with electrostatic electron suppressor were studied numerically by tracing the orbits of fast primary ions and secondary charged particles generated along their beam path by collision with background gas molecules. It is shown that, in reference to the electrostatic field potential at the point of impact, the energy distribution of secondary ions impinging on the suppressor has two peaks-one corresponding to a zone of high positive potential surrounding the collector and the other to one of slightly negative potential around the electron suppressor. Secondary electron emission from the suppressor is ascribed mainly to the latter peak, associated with impingement of slower secondary ions. Far much power consumed in secondary particle acceleration is spent for emitting electrons from the suppressor than for secondary ions generated by beam-gas collision. The upper limit of background pressure is discussed on the basis of criteria prescribed for restricting the power consumed in this secondary particle acceleration, as for practical convenience of electrode cooling. Numerical examples are given of calculations based on particle trajectory analysis of both primary ions and secondary particles, for the case of a 100 keV-proton sheet beam 10 cm thick of 35 mA/cm 2 current density. (author)

  7. The human ARF tumor suppressor senses blastema activity and suppresses epimorphic tissue regeneration

    Science.gov (United States)

    Hesse, Robert G; Kouklis, Gayle K; Ahituv, Nadav; Pomerantz, Jason H

    2015-01-01

    The control of proliferation and differentiation by tumor suppressor genes suggests that evolution of divergent tumor suppressor repertoires could influence species’ regenerative capacity. To directly test that premise, we humanized the zebrafish p53 pathway by introducing regulatory and coding sequences of the human tumor suppressor ARF into the zebrafish genome. ARF was dormant during development, in uninjured adult fins, and during wound healing, but was highly expressed in the blastema during epimorphic fin regeneration after amputation. Regenerative, but not developmental signals resulted in binding of zebrafish E2f to the human ARF promoter and activated conserved ARF-dependent Tp53 functions. The context-dependent activation of ARF did not affect growth and development but inhibited regeneration, an unexpected distinct tumor suppressor response to regenerative versus developmental environments. The antagonistic pleiotropic characteristics of ARF as both tumor and regeneration suppressor imply that inducing epimorphic regeneration clinically would require modulation of ARF –p53 axis activation. DOI: http://dx.doi.org/10.7554/eLife.07702.001 PMID:26575287

  8. Diacylglycerol lipase a knockout mice demonstrate metabolic and behavioral phenotypes similar to those of cannabinoid receptor 1 knockout mice

    Directory of Open Access Journals (Sweden)

    David R Powell

    2015-06-01

    Full Text Available After creating >4650 knockouts (KOs of independent mouse genes, we screened them by high-throughput phenotyping and found that cannabinoid receptor 1 (Cnr1 KO mice had the same lean phenotype published by others. We asked if our KOs of DAG lipase a or b (Dagla or Daglb, which catalyze biosynthesis of the endocannabinoid (EC 2-Arachidonoylglycerol (2-AG, or Napepld, which catalyzes biosynthesis of the EC anandamide, shared the lean phenotype of Cnr1 KO mice. We found that Dagla KO mice, but not Daglb or Napepld KO mice, were among the leanest of 3651 chow-fed KO lines screened. In confirmatory studies, chow- or high fat diet-fed Dagla and Cnr1 KO mice were leaner than wild type (WT littermates; when data from multiple cohorts of adult mice were combined, body fat was 47% and 45% lower in Dagla and Cnr1 KO mice, respectively, relative to WT values. In contrast, neither Daglb nor Napepld KO mice were lean. Weanling Dagla KO mice ate less than WT mice and had body weight similar to pair-fed WT mice, and adult Dagla KO mice had normal activity and VO2 levels, similar to Cnr1 KO mice. Our Dagla and Cnr1 KO mice also had low fasting insulin, triglyceride and total cholesterol levels, and after a glucose challenge had normal glucose but very low insulin levels. Dagla and Cnr1 KO mice also showed similar responses to a battery of behavioral tests. These data suggest: 1 the lean phenotype of young Dagla and Cnr1 KO mice is mainly due to hypophagia; 2 in pathways where ECs signal through Cnr1 to regulate food intake and other metabolic and behavioral phenotypes observed in Cnr1 KO mice, Dagla alone provides the 2-AG that serves as the EC signal; and 3 small molecule Dagla inhibitors with a pharmacokinetic profile similar to that of Cnr1 inverse agonists are likely to mirror the ability of these Cnr1 inverse agonists to lower body weight and improve glycemic control in obese patients with type 2 diabetes, but may also induce undesirable neuropsychiatric

  9. The Knockout of Secretin in Cerebellar Purkinje Cells Impairs Mouse Motor Coordination and Motor Learning

    Science.gov (United States)

    Zhang, Li; Chung, Sookja Kim; Chow, Billy Kwok Chong

    2014-01-01

    Secretin (SCT) was first considered to be a gut hormone regulating gastrointestinal functions when discovered. Recently, however, central actions of SCT have drawn intense research interest and are supported by the broad distribution of SCT in specific neuronal populations and by in vivo physiological studies regarding its role in water homeostasis and food intake. The direct action of SCT on a central neuron was first discovered in cerebellar Purkinje cells in which SCT from cerebellar Purkinje cells was found to potentiate GABAergic inhibitory transmission from presynaptic basket cells. Because Purkinje neurons have a major role in motor coordination and learning functions, we hypothesize a behavioral modulatory function for SCT. In this study, we successfully generated a mouse model in which the SCT gene was deleted specifically in Purkinje cells. This mouse line was tested together with SCT knockout and SCT receptor knockout mice in a full battery of behavioral tasks. We found that the knockout of SCT in Purkinje neurons did not affect general motor ability or the anxiety level in open field tests. However, knockout mice did exhibit impairments in neuromuscular strength, motor coordination, and motor learning abilities, as shown by wire hanging, vertical climbing, and rotarod tests. In addition, SCT knockout in Purkinje cells possibly led to the delayed development of motor neurons, as supported by the later occurrence of key neural reflexes. In summary, our data suggest a role in motor coordination and motor learning for SCT expressed in cerebellar Purkinje cells. PMID:24356714

  10. Knockouts of high-ranking males have limited impact on baboon social networks.

    Science.gov (United States)

    Franz, Mathias; Altmann, Jeanne; Alberts, Susan C

    Social network structures can crucially impact complex social processes such as collective behaviour or the transmission of information and diseases. However, currently it is poorly understood how social networks change over time. Previous studies on primates suggest that `knockouts' (due to death or dispersal) of high-ranking individuals might be important drivers for structural changes in animal social networks. Here we test this hypothesis using long-term data on a natural population of baboons, examining the effects of 29 natural knockouts of alpha or beta males on adult female social networks. We investigated whether and how knockouts affected (1) changes in grooming and association rates among adult females, and (2) changes in mean degree and global clustering coefficient in these networks. The only significant effect that we found was a decrease in mean degree in grooming networks in the first month after knockouts, but this decrease was rather small, and grooming networks rebounded to baseline levels by the second month after knockouts. Taken together our results indicate that the removal of high-ranking males has only limited or no lasting effects on social networks of adult female baboons. This finding calls into question the hypothesis that the removal of high-ranking individuals has a destabilizing effect on social network structures in social animals.

  11. Stabilization of tooth movement by administration of reveromycin A to osteoprotegerin-deficient knockout mice.

    Science.gov (United States)

    Yabumoto, Takahiro; Miyazawa, Ken; Tabuchi, Masako; Shoji, Satsuki; Tanaka, Miyuki; Kadota, Manami; Yoshizako, Mamoru; Kawatani, Makoto; Osada, Hiroyuki; Maeda, Hatsuhiko; Goto, Shigemi

    2013-09-01

    In this study, mechanical stress in the form of tooth movement was applied to osteoprotegerin-deficient knockout mice, which served as an animal model for juvenile Paget's disease. To compare and evaluate bone turnover and response of the surrounding bony tissue, we administered reveromycin A. We also investigated the ability of reveromycin A to control osteoclastic activity in juvenile Paget's disease. Eight-week-old male osteoprotegerin-deficient knockout and wild-type mice were injected with reveromycin A (15 mg/kg of body weight) intraperitoneally twice daily. An elastic module was inserted interproximally between the maxillary left first and second molars. Administration of reveromycin A to osteoprotegerin-deficient knockout mice reduced tooth movement distances, increased bone volumes at the interradicular septum, decreased osteoclast counts, and reduced serum alkaline phosphatase and tartrate resistant acid phosphatase. Reveromycin A administration also caused a temporal shift in peak Runx2 staining in osteoprotegerin-deficient knockout mice so that the overall staining time course was similar to that observed for wild-type mice. Reveromycin A administration in osteoprotegerin-deficient knockout mice inhibited bone resorption and normalized bone formation. As a result, normal bone turnover was obtained. Copyright © 2013 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

  12. Gene Knockout Identification Using an Extension of Bees Hill Flux Balance Analysis

    Directory of Open Access Journals (Sweden)

    Yee Wen Choon

    2015-01-01

    Full Text Available Microbial strain optimisation for the overproduction of a desired phenotype has been a popular topic in recent years. Gene knockout is a genetic engineering technique that can modify the metabolism of microbial cells to obtain desirable phenotypes. Optimisation algorithms have been developed to identify the effects of gene knockout. However, the complexities of metabolic networks have made the process of identifying the effects of genetic modification on desirable phenotypes challenging. Furthermore, a vast number of reactions in cellular metabolism often lead to a combinatorial problem in obtaining optimal gene knockout. The computational time increases exponentially as the size of the problem increases. This work reports an extension of Bees Hill Flux Balance Analysis (BHFBA to identify optimal gene knockouts to maximise the production yield of desired phenotypes while sustaining the growth rate. This proposed method functions by integrating OptKnock into BHFBA for validating the results automatically. The results show that the extension of BHFBA is suitable, reliable, and applicable in predicting gene knockout. Through several experiments conducted on Escherichia coli, Bacillus subtilis, and Clostridium thermocellum as model organisms, extension of BHFBA has shown better performance in terms of computational time, stability, growth rate, and production yield of desired phenotypes.

  13. V2 from a curtovirus is a suppressor of post-transcriptional gene silencing.

    Science.gov (United States)

    Luna, Ana P; Rodríguez-Negrete, Edgar A; Morilla, Gabriel; Wang, Liping; Lozano-Durán, Rosa; Castillo, Araceli G; Bejarano, Eduardo R

    2017-10-01

    The suppression of gene silencing is a key mechanism for the success of viral infection in plants. DNA viruses from the Geminiviridae family encode several proteins that suppress transcriptional and post-transcriptional gene silencing (TGS/PTGS). In Begomovirus, the most abundant genus of this family, three out of six genome-encoded proteins, namely C2, C4 and V2, have been shown to suppress PTGS, with V2 being the strongest PTGS suppressor in transient assays. Beet curly top virus (BCTV), the model species for the Curtovirus genus, is able to infect the widest range of plants among geminiviruses. In this genus, only one protein, C2/L2, has been described as inhibiting PTGS. We show here that, despite the lack of sequence homology with its begomoviral counterpart, BCTV V2 acts as a potent PTGS suppressor, possibly by impairing the RDR6 (RNA-dependent RNA polymerase 6)/suppressor of gene silencing 3 (SGS3) pathway.

  14. THE MOLECULAR BASIS OF SUPPRESSION IN AN OCHRE SUPPRESSOR STRAIN POSSESSING ALTERED RIBOSOMES*

    Science.gov (United States)

    Gartner, T. Kent; Orias, Eduardo; Lannan, James E.; Beeson, James; Reid, Parlane J.

    1969-01-01

    Escherichia coli K12 2320(λ)-15B has a mutation that results in ochre suppressor activity.1 This mutation concomitantly causes a decreased growth rate in rich medium, an increased sensitivity to streptomycin,1 and the production of some altered 30S ribosomes which are differentially sensitive to RNase.2 The results presented below demonstrate that the molecules which cause suppression are tRNA. These observations justify the conclusions that the suppressor mutation did not occur in a structural gene for a ribosomal component, and that the decreased growth rate in rich medium, the increased sensitivity to streptomycin, and the production of altered 30S ribosomes are probably all secondary consequences of the suppressor mutation. PMID:4895220

  15. The potential for tumor suppressor gene therapy in head and neck cancer.

    Science.gov (United States)

    Birkeland, Andrew C; Ludwig, Megan L; Spector, Matthew E; Brenner, J Chad

    2016-01-01

    Head and neck squamous cell carcinoma remains a highly morbid and fatal disease. Importantly, genomic sequencing of head and neck cancers has identified frequent mutations in tumor suppressor genes. While targeted therapeutics increasingly are being investigated in head and neck cancer, the majority of these agents are against overactive/overexpressed oncogenes. Therapy to restore lost tumor suppressor gene function remains a key and under-addressed niche in trials for head and neck cancer. Recent advances in gene editing have captured the interest of both the scientific community and the public. As our technology for gene editing and gene expression modulation improves, addressing lost tumor suppressor gene function in head and neck cancers is becoming a reality. This review will summarize new techniques, challenges to implementation, future directions, and ethical ramifications of gene therapy in head and neck cancer.

  16. The molecular effect of metastasis suppressors on Src signaling and tumorigenesis: new therapeutic targets

    Science.gov (United States)

    Liu, Wensheng; Kovacevic, Zaklina; Peng, Zhihai; Jin, Runsen; Wang, Puxiongzhi; Yue, Fei; Zheng, Minhua; Huang, Michael L-H.; Jansson, Patric J.; Richardson, Vera; Kalinowski, Danuta S.; Lane, Darius J.R.; Merlot, Angelica M.; Sahni, Sumit; Richardson, Des R.

    2015-01-01

    A major problem for cancer patients is the metastasis of cancer cells from the primary tumor. This involves: (1) migration through the basement membrane; (2) dissemination via the circulatory system; and (3) invasion into a secondary site. Metastasis suppressors, by definition, inhibit metastasis at any step of the metastatic cascade. Notably, Src is a non-receptor, cytoplasmic, tyrosine kinase, which becomes aberrantly activated in many cancer-types following stimulation of plasma membrane receptors (e.g., receptor tyrosine kinases and integrins). There is evidence of a prominent role of Src in tumor progression-related events such as the epithelial–mesenchymal transition (EMT) and the development of metastasis. However, the precise molecular interactions of Src with metastasis suppressors remain unclear. Herein, we review known metastasis suppressors and summarize recent advances in understanding the mechanisms of how these proteins inhibit metastasis through modulation of Src. Particular emphasis is bestowed on the potent metastasis suppressor, N-myc downstream regulated gene 1 (NDRG1) and its interactions with the Src signaling cascade. Recent studies demonstrated a novel mechanism through which NDRG1 plays a significant role in regulating cancer cell migration by inhibiting Src activity. Moreover, we discuss the rationale for targeting metastasis suppressor genes as a sound therapeutic modality, and we review several examples from the literature where such strategies show promise. Collectively, this review summarizes the essential interactions of metastasis suppressors with Src and their effects on progression of cancer metastasis. Moreover, interesting unresolved issues regarding these proteins as well as their potential as therapeutic targets are also discussed. PMID:26431493

  17. Supervised learning classification models for prediction of plant virus encoded RNA silencing suppressors.

    Directory of Open Access Journals (Sweden)

    Zeenia Jagga

    Full Text Available Viral encoded RNA silencing suppressor proteins interfere with the host RNA silencing machinery, facilitating viral infection by evading host immunity. In plant hosts, the viral proteins have several basic science implications and biotechnology applications. However in silico identification of these proteins is limited by their high sequence diversity. In this study we developed supervised learning based classification models for plant viral RNA silencing suppressor proteins in plant viruses. We developed four classifiers based on supervised learning algorithms: J48, Random Forest, LibSVM and Naïve Bayes algorithms, with enriched model learning by correlation based feature selection. Structural and physicochemical features calculated for experimentally verified primary protein sequences were used to train the classifiers. The training features include amino acid composition; auto correlation coefficients; composition, transition, and distribution of various physicochemical properties; and pseudo amino acid composition. Performance analysis of predictive models based on 10 fold cross-validation and independent data testing revealed that the Random Forest based model was the best and achieved 86.11% overall accuracy and 86.22% balanced accuracy with a remarkably high area under the Receivers Operating Characteristic curve of 0.95 to predict viral RNA silencing suppressor proteins. The prediction models for plant viral RNA silencing suppressors can potentially aid identification of novel viral RNA silencing suppressors, which will provide valuable insights into the mechanism of RNA silencing and could be further explored as potential targets for designing novel antiviral therapeutics. Also, the key subset of identified optimal features may help in determining compositional patterns in the viral proteins which are important determinants for RNA silencing suppressor activities. The best prediction model developed in the study is available as a

  18. High-temperature expansion and knock-out properties of moulding sands with water glass

    Directory of Open Access Journals (Sweden)

    Major-Gabryś K.

    2007-01-01

    Full Text Available The article focuses on the topic of improving the knock-out properties of moulding sand with water glass and ester hardener. It is settled that the cause of worse knock-out properties of moulding sand can be brought by their thermal expansion in increased temperatures. There is a presentation of the influence of different additives, containing Al2O3, on moulding sands’ expansion in increased temperatures. Within the frames of research, there was an elaboration of the influence of authors own additive- Glassex, on the expansion phenomenon of moulding sands with water glass and ester hardener. It is concluded, that the new additive stops the expansion of moulding sands and as well it improves their knock-out properties.

  19. Impaired water maze learning performance in mu-opioid receptor knockout mice.

    Science.gov (United States)

    Jang, Choon-Gon; Lee, Seok-Yong; Yoo, Ji-Hoon; Yan, Ji-Jing; Song, Dong-Keun; Loh, Horace H; Ho, Ing K

    2003-09-10

    Previous study has demonstrated that the lack of mu-opioid receptor decreased LTP in the dentate gyrus of the hippocampus, suggesting the possibility that the lack of mu-opioid receptor may accompany a change in learning and memory. However, no behavioral study has been undertaken to correlate LTP deficits with spatial memory impairment in mu-opioid receptor knockout mice. Therefore, the present study investigated the hypothesis that mu-opioid receptors contribute to learning and memory by using the Morris water maze, and comparing responses in wild type and mu-opioid receptor gene knockout mice. Our results indicated that mu-opioid receptor knockout mice showed a significant spatial memory impairment compared to wild type in the Morris water maze. This result suggests that the expression of mu-opioid receptor plays an important role in spatial learning and memory examined by Morris water maze.

  20. Clinical impact of the immunome in lymphoid malignancies: the role of Myeloid-Derived Suppressor Cells

    Directory of Open Access Journals (Sweden)

    Calogero eVetro

    2015-05-01

    Full Text Available The better definition of the mutual sustainment between neoplastic cells and immune system has been translated from the bench to the bedside acquiring value as prognostic factor. Additionally, it represents a promising tool for improving therapeutic strategies. In this context, myeloid-derived suppressor cells have gained a central role in tumor developing with consequent therapeutic implications. In this review, we will focus on the biological and clinical impact of the study of myeloid-derived suppressor cells in the settings of lymphoid malignancies.

  1. Altered metabolism in the melatonin-related receptor (GPR50) knockout mouse.

    Science.gov (United States)

    Ivanova, Elena A; Bechtold, David A; Dupré, Sandrine M; Brennand, John; Barrett, Perry; Luckman, Simon M; Loudon, Andrew S I

    2008-01-01

    The X-linked orphan receptor GPR50 shares 45% homology with the melatonin receptors, yet its ligand and physiological function remain unknown. Here we report that mice lacking functional GPR50 through insertion of a lacZ gene into the coding sequence of GPR50 exhibit an altered metabolic phenotype. GPR50 knockout mice maintained on normal chow exhibit lower body weight than age-matched wild-type littermates by 10 wk of age. Furthermore, knockout mice were partially resistant to diet-induced obesity. When placed on a high-energy diet (HED) for 5 wk, knockout mice consumed significantly more food per unit body weight yet exhibited an attenuated weight gain and reduced body fat content compared with wild-type mice. Wheel-running activity records revealed that, although GPR50 knockout mice showed no alteration of circadian period, the overall levels of activity were significantly increased over wild types in both nocturnal and diurnal phases. In line with this, basal metabolic rate (O2 consumption, CO2 production, and respiratory quotient) was found to be elevated in knockout mice. Using in situ hybridization (wild-type mice) and beta-galactosidase activity (from LacZ insertion element in knockout mice), brain expression of GPR50 was found to be restricted to the ependymal layer of the third ventricle and dorsomedial nucleus of the hypothalamus. GPR50 expression was highly responsive to energy status, showing a significantly reduced expression following both fasting and 5 wk of HED. These data implicate GPR50 as an important regulator of energy metabolism.

  2. Evaluation and Design of Genome-Wide CRISPR/SpCas9 Knockout Screens

    Directory of Open Access Journals (Sweden)

    Traver Hart

    2017-08-01

    Full Text Available The adaptation of CRISPR/SpCas9 technology to mammalian cell lines is transforming the study of human functional genomics. Pooled libraries of CRISPR guide RNAs (gRNAs targeting human protein-coding genes and encoded in viral vectors have been used to systematically create gene knockouts in a variety of human cancer and immortalized cell lines, in an effort to identify whether these knockouts cause cellular fitness defects. Previous work has shown that CRISPR screens are more sensitive and specific than pooled-library shRNA screens in similar assays, but currently there exists significant variability across CRISPR library designs and experimental protocols. In this study, we reanalyze 17 genome-scale knockout screens in human cell lines from three research groups, using three different genome-scale gRNA libraries. Using the Bayesian Analysis of Gene Essentiality algorithm to identify essential genes, we refine and expand our previously defined set of human core essential genes from 360 to 684 genes. We use this expanded set of reference core essential genes, CEG2, plus empirical data from six CRISPR knockout screens to guide the design of a sequence-optimized gRNA library, the Toronto KnockOut version 3.0 (TKOv3 library. We then demonstrate the high effectiveness of the library relative to reference sets of essential and nonessential genes, as well as other screens using similar approaches. The optimized TKOv3 library, combined with the CEG2 reference set, provide an efficient, highly optimized platform for performing and assessing gene knockout screens in human cell lines.

  3. Hyperactivity of Newborn Pten Knock-out Neurons Results from Increased Excitatory Synaptic Drive

    Science.gov (United States)

    Williams, Michael R.; DeSpenza, Tyrone; Li, Meijie; Gulledge, Allan T.

    2015-01-01

    Developing neurons must regulate morphology, intrinsic excitability, and synaptogenesis to form neural circuits. When these processes go awry, disorders, including autism spectrum disorder (ASD) or epilepsy, may result. The phosphatase Pten is mutated in some patients having ASD and seizures, suggesting that its mutation disrupts neurological function in part through increasing neuronal activity. Supporting this idea, neuronal knock-out of Pten in mice can cause macrocephaly, behavioral changes similar to ASD, and seizures. However, the mechanisms through which excitability is enhanced following Pten depletion are unclear. Previous studies have separately shown that Pten-depleted neurons can drive seizures, receive elevated excitatory synaptic input, and have abnormal dendrites. We therefore tested the hypothesis that developing Pten-depleted neurons are hyperactive due to increased excitatory synaptogenesis using electrophysiology, calcium imaging, morphological analyses, and modeling. This was accomplished by coinjecting retroviruses to either “birthdate” or birthdate and knock-out Pten in granule neurons of the murine neonatal dentate gyrus. We found that Pten knock-out neurons, despite a rapid onset of hypertrophy, were more active in vivo. Pten knock-out neurons fired at more hyperpolarized membrane potentials, displayed greater peak spike rates, and were more sensitive to depolarizing synaptic input. The increased sensitivity of Pten knock-out neurons was due, in part, to a higher density of synapses located more proximal to the soma. We determined that increased synaptic drive was sufficient to drive hypertrophic Pten knock-out neurons beyond their altered action potential threshold. Thus, our work contributes a developmental mechanism for the increased activity of Pten-depleted neurons. PMID:25609613

  4. Evaluation and Design of Genome-Wide CRISPR/SpCas9 Knockout Screens

    Science.gov (United States)

    Hart, Traver; Tong, Amy Hin Yan; Chan, Katie; Van Leeuwen, Jolanda; Seetharaman, Ashwin; Aregger, Michael; Chandrashekhar, Megha; Hustedt, Nicole; Seth, Sahil; Noonan, Avery; Habsid, Andrea; Sizova, Olga; Nedyalkova, Lyudmila; Climie, Ryan; Tworzyanski, Leanne; Lawson, Keith; Sartori, Maria Augusta; Alibeh, Sabriyeh; Tieu, David; Masud, Sanna; Mero, Patricia; Weiss, Alexander; Brown, Kevin R.; Usaj, Matej; Billmann, Maximilian; Rahman, Mahfuzur; Costanzo, Michael; Myers, Chad L.; Andrews, Brenda J.; Boone, Charles; Durocher, Daniel; Moffat, Jason

    2017-01-01

    The adaptation of CRISPR/SpCas9 technology to mammalian cell lines is transforming the study of human functional genomics. Pooled libraries of CRISPR guide RNAs (gRNAs) targeting human protein-coding genes and encoded in viral vectors have been used to systematically create gene knockouts in a variety of human cancer and immortalized cell lines, in an effort to identify whether these knockouts cause cellular fitness defects. Previous work has shown that CRISPR screens are more sensitive and specific than pooled-library shRNA screens in similar assays, but currently there exists significant variability across CRISPR library designs and experimental protocols. In this study, we reanalyze 17 genome-scale knockout screens in human cell lines from three research groups, using three different genome-scale gRNA libraries. Using the Bayesian Analysis of Gene Essentiality algorithm to identify essential genes, we refine and expand our previously defined set of human core essential genes from 360 to 684 genes. We use this expanded set of reference core essential genes, CEG2, plus empirical data from six CRISPR knockout screens to guide the design of a sequence-optimized gRNA library, the Toronto KnockOut version 3.0 (TKOv3) library. We then demonstrate the high effectiveness of the library relative to reference sets of essential and nonessential genes, as well as other screens using similar approaches. The optimized TKOv3 library, combined with the CEG2 reference set, provide an efficient, highly optimized platform for performing and assessing gene knockout screens in human cell lines. PMID:28655737

  5. Data on the effect of knockout of cytohesin-1 in myelination-related protein kinase signaling.

    Science.gov (United States)

    Tsuneishi, Ruri; Matsumoto, Naoto; Itaoka, Misa; Urai, Yuri; Kaneko, Minami; Watanabe, Natsumi; Takashima, Shou; Seki, Yoichi; Morimoto, Takako; Sakagami, Hiroyuki; Miyamoto, Yuki; Yamauchi, Junji

    2017-12-01

    Cytohesin-1 is the guanine-nucleotide exchange factor of Arf6, a small GTPase of Arf family, and participates in cellular morphological changes. Knockout mice of cytohesin-1 exhibit decreased myelination of neuronal axons in the peripheral nervous system (PNS) "Phosphorylation of cytohesin-1 by Fyn is required for initiation of myelination and the extent of myelination during development (Yamauchi et al., 2012) [1]". Herein we provide the data regarding decreased phosphorylation levels of protein kinases involved in two major myelination-related kinase cascades in cytohesin-1 knockout mice.

  6. Suppressor of cytokine signaling 3 knockdown in the mediobasal hypothalamus: counterintuitive effects on energy balance

    NARCIS (Netherlands)

    de Backer, M. W. A.; Brans, M. A. D.; van Rozen, A. J.; van der Zwaal, E. M.; Luijendijk, M. C. M.; Garner, K. G.; de Krom, M.; van Beekum, O.; La Fleur, S. E.; Adan, R. A. H.

    2010-01-01

    An increase in brain suppressor of cytokine signaling 3 (SOCS3) has been implicated in the development of both leptin and insulin resistance. Socs3 mRNA is localized throughout the brain, and it remains unclear which brain areas are involved in the effect of SOCS3 levels on energy balance. We

  7. Alterations in tumour suppressor gene p53 in human gliomas from ...

    Indian Academy of Sciences (India)

    Unknown

    [Phatak P, Selvi S K, Divya T, Hegde A S, Hegde S and Somasundaram K 2002 Alterations in tumour suppressor gene p53 in human gliomas from Indian patients; J. Biosci. 27 673–678]. 1. Introduction. Glioma, a neoplasm of neuroglial cells, is the most common type of brain tumour, constituting more than 50% of all.

  8. BASP1 is a transcriptional cosuppressor for the Wilms' tumor suppressor protein WT1

    DEFF Research Database (Denmark)

    Carpenter, Brian; Hill, Kathryn J; Charalambous, Marika

    2004-01-01

    The Wilms' tumor suppressor protein WT1 is a transcriptional regulator that plays a key role in the development of the kidneys. The transcriptional activation domain of WT1 is subject to regulation by a suppression region within the N terminus of WT1. Using a functional assay, we provide direct e...

  9. Distinct Effects of p19 RNA Silencing Suppressor on Small RNA Mediated Pathways in Plants.

    Directory of Open Access Journals (Sweden)

    Levente Kontra

    2016-10-01

    Full Text Available RNA silencing is one of the main defense mechanisms employed by plants to fight viruses. In change, viruses have evolved silencing suppressor proteins to neutralize antiviral silencing. Since the endogenous and antiviral functions of RNA silencing pathway rely on common components, it was suggested that viral suppressors interfere with endogenous silencing pathway contributing to viral symptom development. In this work, we aimed to understand the effects of the tombusviral p19 suppressor on endogenous and antiviral silencing during genuine virus infection. We showed that ectopically expressed p19 sequesters endogenous small RNAs (sRNAs in the absence, but not in the presence of virus infection. Our presented data question the generalized model in which the sequestration of endogenous sRNAs by the viral suppressor contributes to the viral symptom development. We further showed that p19 preferentially binds the perfectly paired ds-viral small interfering RNAs (vsiRNAs but does not select based on their sequence or the type of the 5' nucleotide. Finally, co-immunoprecipitation of sRNAs with AGO1 or AGO2 from virus-infected plants revealed that p19 specifically impairs vsiRNA loading into AGO1 but not AGO2. Our findings, coupled with the fact that p19-expressing wild type Cymbidium ringspot virus (CymRSV overcomes the Nicotiana benthamiana silencing based defense killing the host, suggest that AGO1 is the main effector of antiviral silencing in this host-virus combination.

  10. Suppressor Effects in Coping Research with African American Adolescents from Low-Income Communities

    Science.gov (United States)

    Gaylord-Harden, Noni K.; Cunningham, Jamila A.; Holmbeck, Grayson N.; Grant, Kathryn E.

    2010-01-01

    Objective: The purpose of the current study was to demonstrate the replicable nature of statistical suppressor effects in coping research through 2 examples with African American adolescents from low-income communities. Method: Participants in the 1st example included 497 African American adolescents (mean age = 12.61 years, SD = 0.99; 57% female)…

  11. Haploinsufficiency of the genes encoding the tumor suppressor Pten predisposes zebrafish to hemangiosarcoma

    NARCIS (Netherlands)

    Choorapoikayil, S.; Kuiper, R.V.; de Bruin, A.; den Hertog, J.

    2012-01-01

    PTEN is an essential tumor suppressor that antagonizes Akt/PKB signaling. The zebrafish genome encodes two Pten genes, ptena and ptenb. Here, we report that zebrafish mutants that retain a single wild-type copy of ptena or ptenb (ptena(+/-)ptenb(-/-) or ptena(-/-)ptenb(+/-)) are viable and fertile.

  12. Influence of anticancer drugs on interactions of tumor suppressor protein p53 with DNA

    Czech Academy of Sciences Publication Activity Database

    Pivoňková, Hana; Němcová, Kateřina; Brázdová, Marie; Kašpárková, Jana; Brabec, Viktor; Fojta, Miroslav

    2005-01-01

    Roč. 272, Suppl. 1 (2005), s. 562 ISSN 1474-3833. [FEBS Congress /30./ and IUBMB Conference /9./. 02.07.2005-07.07.2005, Budapest] R&D Projects: GA MZd(CZ) NC7574 Institutional research plan: CEZ:AV0Z50040507 Keywords : tumour suppressor protein p53 * anticancer drugs * interaction with DNA Subject RIV: BO - Biophysics

  13. Analyses of tumor-suppressor genes in germline mouse models of cancer.

    Science.gov (United States)

    Wang, Jingqiang; Abate-Shen, Cory

    2014-08-01

    Tumor-suppressor genes are critical regulators of growth and functioning of cells, whose loss of function contributes to tumorigenesis. Accordingly, analyses of the consequences of their loss of function in genetically engineered mouse models have provided important insights into mechanisms of human cancer, as well as resources for preclinical analyses and biomarker discovery. Nowadays, most investigations of genetically engineered mouse models of tumor-suppressor function use conditional or inducible alleles, which enable analyses in specific cancer (tissue) types and overcome the consequences of embryonic lethality of germline loss of function of essential tumor-suppressor genes. However, historically, analyses of genetically engineered mouse models based on germline loss of function of tumor-suppressor genes were very important as these early studies established the principle that loss of function could be studied in mouse cancer models and also enabled analyses of these essential genes in an organismal context. Although the cancer phenotypes of these early germline models did not always recapitulate the expected phenotypes in human cancer, these models provided the essential foundation for the more sophisticated conditional and inducible models that are currently in use. Here, we describe these "first-generation" germline models of loss of function models, focusing on the important lessons learned from their analyses, which helped in the design and analyses of "next-generation" genetically engineered mouse models. © 2014 Cold Spring Harbor Laboratory Press.

  14. Mechanism of inhibition of growth hormone receptor signaling by suppressor of cytokine signaling proteins

    DEFF Research Database (Denmark)

    Hansen, J A; Lindberg, K; Hilton, D J

    1999-01-01

    In this study we have investigated the role of suppressor of cytokine signaling (SOCS) proteins in GH receptor-mediated signaling. GH-induced transcription was inhibited by SOCS-1 and SOCS-3, while SOCS-2 and cytokine inducible SH2-containing protein (CIS) had no effect By using chimeric SOCS pro...

  15. Alterations in tumour suppressor gene p53 in human gliomas from ...

    Indian Academy of Sciences (India)

    Unknown

    Alterations in the tumour suppressor p53 gene are among the most common defects seen in a variety of human cancers. In order ... from Indian patients, we checked 44 untreated primary gliomas for mutations in exons 5–9 of the p53 gene by. PCR-SSCP ... function of p53 is critical to the efficiency of many cancer treatment ...

  16. Alterations in tumour suppressor gene p53 in human gliomas from ...

    Indian Academy of Sciences (India)

    Alterations in the tumour suppressor p53 gene are among the most common defects seen in a variety of human cancers. In order to study the significance of the p53 gene in the genesis and development of human glioma from Indian patients, we checked 44 untreated primary gliomas for mutations in exons 5–9 of the p53 ...

  17. Myeloid derived suppressor cells-An overview of combat strategies to increase immunotherapy efficacy

    NARCIS (Netherlands)

    Draghiciu, Oana; Lubbers, Joyce; Nijman, Hans W.; Daemen, Toos

    2015-01-01

    Myeloid-derived suppressor cells (MDSCs) contribute to tumor-mediated immune escape and negatively correlate with overall survival of cancer patients. Nowadays, a variety of methods to target MDSCs are being investigated. Based on the intervention stage of MDSCs, namely development, expansion and

  18. TFPI-2 is a putative tumor suppressor gene frequently inactivated by promoter hypermethylation in nasopharyngeal carcinoma

    International Nuclear Information System (INIS)

    Wang, Shumin; Ma, Ning; Murata, Mariko; Huang, Guangwu; Zhang, Zhe; Xiao, Xue; Zhou, Xiaoying; Huang, Tingting; Du, Chunping; Yu, Nana; Mo, Yingxi; Lin, Longde; Zhang, Jinyan

    2010-01-01

    Epigenetic silencing of tumor suppressor genes play important roles in NPC tumorgenesis. Tissue factor pathway inhibitor-2 (TFPI-2), is a protease inhibitor. Recently, TFPI-2 was suggested to be a tumor suppressor gene involved in tumorigenesis and metastasis in some cancers. In this study, we investigated whether TFPI-2 was inactivated epigenetically in nasopharyngeal carcinoma (NPC). Transcriptional expression levels of TFPI-2 was evaluated by RT-PCR. Methylation status were investigated by methylation specific PCR and bisulfate genomic sequencing. The role of TFPI-2 as a tumor suppressor gene in NPC was addressed by re-introducing TFPI-2 expression into the NPC cell line CNE2. TFPI-2 mRNA transcription was inactivated in NPC cell lines. TFPI-2 was aberrantly methylated in 66.7% (4/6) NPC cell lines and 88.6% (62/70) of NPC primary tumors, but not in normal nasopharyngeal epithelia. TFPI-2 expression could be restored in NPC cells after demethylation treatment. Ectopic expression of TFPI-2 in NPC cells induced apoptosis and inhibited cell proliferation, colony formation and cell migration. Epigenetic inactivation of TFPI-2 by promoter hypermethylation is a frequent and tumor specific event in NPC. TFPI-2 might be considering as a putative tumor suppressor gene in NPC

  19. Phytosterol Feeding Causes Toxicity in ABCG5/G8 Knockout Mice

    Science.gov (United States)

    McDaniel, Allison L.; Alger, Heather M.; Sawyer, Janet K.; Kelley, Kathryn L.; Kock, Nancy D.; Brown, J. Mark; Temel, Ryan E.; Rudel, Lawrence L.

    2014-01-01

    Plant sterols, or phytosterols, are very similar in structure to cholesterol and are abundant in typical diets. The reason for poor absorption of plant sterols by the body is still unknown. Mutations in the ABC transporters G5 and G8 are known to cause an accumulation of plant sterols in blood and tissues (sitosterolemia). To determine the significance of phytosterol exclusion from the body, we fed wild-type and ABCG5/G8 knockout mice a diet enriched with plant sterols. The high-phytosterol diet was extremely toxic to the ABCG5/G8 knockout mice but had no adverse effects on wild-type mice. ABCG5/G8 knockout mice died prematurely and developed a phenotype that included high levels of plant sterols in many tissues, liver abnormalities, and severe cardiac lesions. This study is the first to report such toxic effects of phytosterol accumulation in ABCG5/G8 knockout mice. We believe these new data support the conclusion that plant sterols are excluded from the body because they are toxic when present at high levels. PMID:23380580

  20. Age-Related Changes in the Behavior of Apolipoprotein E Knockout Mice.

    Science.gov (United States)

    Fuentes, Dasha; Fernández, Nidia; García, Yenela; García, Teidy; Morales, Ana Ruth; Menéndez, Roberto

    2018-03-03

    The knockout mouse model, B6.129P2-Apoe tm1Unc is homozygotic for the Apolipoprotein E (ApoE) deletion; thus, it is capable of developing hyperlipidemia and atherosclerosis but ApoE is also a lipid-transport protein abundantly expressed in most neurons in the central nervous system, so these animals could also be models of neurodegenerative diseases. The aim of this study was to determine age-related changes in spontaneous behavior and in learning and memory of Apolipoprotein E knockout mice. Spontaneous behavioral measurements included sleeping pattern, motor coordination and balance by rotarod and open field activity, whereas learning and memory tests included forced alternation in Y-maze, novel object recognition and passive avoidance conditioning. Significant behavioral differences between aged knockout mice and age-matched wild type strain, C57Bl/6 were found in all the behavioral tests, except for the rotarod test. Genetically' modified mice exhibited less huddling contact during sleeping, decreased locomotor activity in novel environments and in learning and memory deficits. These results are consistent with the cognitive impairment and memory loss seen as the earliest clinical symptoms in neurodegenerative disorders such as Alzheimer's disease. The ApoE knockout mice might therefore be an appropriate model for studying the underlying mechanisms involved in behavioral changes caused by neurodegenerative diseases as well as for evaluating new therapies for these pathologies.

  1. Generation and basic characterization of glutamate carboxypeptidase II knock-out mice

    Czech Academy of Sciences Publication Activity Database

    Vorlová, Barbora; Kašpárek, Petr; Šácha, Pavel; Sedláček, Radislav; Konvalinka, Jan

    2016-01-01

    Roč. 25, č. 2 (2016), s. 267 ISSN 0962-8819. [Transgenic Technology Meeting (TT2016) /13./. 20.03.2016-23.03.2016, Praha] Institutional support: RVO:61388963 ; RVO:68378050 Keywords : GCPII * PSMA * FolhI * knock-out mice Subject RIV: CE - Biochemistry

  2. Revealing novel functions of glutamate carboxypeptidase II using knock-out mice

    Czech Academy of Sciences Publication Activity Database

    Vorlová, Barbora; Kašpárek, P.; Šácha, Pavel; Sedláček, R.; Konvalinka, Jan

    2017-01-01

    Roč. 284, Suppl 1 (2017), s. 358 ISSN 1742-464X. [FEBS Congress /42./ From Molecules to Cells and Back. 10.09.2017-14.09.2017, Jerusalem] Institutional support: RVO:61388963 Keywords : glutamate carboxypeptidase II * knock-out mice Subject RIV: CE - Biochemistry

  3. Efficient target-selected mutagenesis in Caenorhabditis elegans : toward a knockout for every gene

    NARCIS (Netherlands)

    Cuppen, Edwin; Gort, Eelke; Hazendonk, Esther; Mudde, Josine; van de Belt, José; Nijman, Isaäc J; Guryev, Victor; Plasterk, Ronald H A

    Reverse genetic or gene-driven knockout approaches have contributed significantly to the success of model organisms for fundamental and biomedical research. Although various technologies are available for C. elegans, none of them scale very well for genome-wide application. To address this, we

  4. Mig-6 Gene Knockout Induces Neointimal Hyperplasia in the Vascular Smooth Muscle Cell

    Directory of Open Access Journals (Sweden)

    Ju Hee Lee

    2014-01-01

    Full Text Available Although advances in vascular interventions can reduce the mortality associated with cardiovascular disease, neointimal hyperplasia remains a clinically significant obstacle limiting the success of current interventions. Identification of signaling pathways involved in migration and proliferation of vascular smooth muscle cells (SMCs is an important approach for the development of modalities to combat this disease. Herein we investigate the role of an immediate early response gene, mitogen-inducible gene-6 (Mig-6, in the development of neointimal hyperplasia using vascular smooth muscle specific Mig-6 knockout mice. We induced endoluminal injury to one side of femoral artery by balloon dilatation in both Mig-6 knockout and control mice. Four weeks following injury, the artery of Mig-6 knockout mice demonstrated a 5.3-fold increase in the neointima/media ratio compared with control mice (P=0.04. In addition, Mig-6 knockout vascular SMCs displayed an increase in both cell migration and proliferation compared with wild-type SMCs. Taken together, our data suggest that Mig-6 plays a critical role in the development of atherosclerosis. This finding provides new insight into the development of more effective ways to treat and prevent neointimal hyperplasia, particularly in-stent restenosis after percutaneous vascular intervention.

  5. Hematopoiesis in 5-Fluorouracil-Treated Adenosine A(3) Receptor Knock-Out Mice

    Czech Academy of Sciences Publication Activity Database

    Hofer, Michal; Pospíšil, Milan; Dušek, L.; Hoferová, Zuzana; Komůrková, Denisa

    2015-01-01

    Roč. 64, č. 2 (2015), s. 255-262 ISSN 0862-8408 Institutional support: RVO:68081707 Keywords : Adenosine A(3) receptor knock-out mice * Hematopoiesis * 5-fluorouracil-induced hematotoxicity Subject RIV: BO - Biophysics Impact factor: 1.643, year: 2015

  6. Pharmacological treatment of fragile X syndrome with GABAergic drugs in a knockout mouse model

    NARCIS (Netherlands)

    Heulens, Inge; D'Hulst, Charlotte; Van Dam, Debby; De Deyn, Peter P.; Kooy, R. Frank

    2012-01-01

    Molecular and electrophysiological studies have provided evidence for a general downregulation of the GABAergic system in the Fmr1 knockout mouse. GABA(A) receptors are the main inhibitory receptors in the brain and the GABA(A) receptor was proposed as a novel target for treatment of the fragile X

  7. Probing the structure of unstable nuclei through the recoiled proton tagged knockout reaction

    International Nuclear Information System (INIS)

    Ye, Y.; Cao, Z.; Jiang, D.

    2010-01-01

    Recoiled proton tagged knockout reaction experiments were carried-out for 8 He at 82,5 MeV/u in RIKEN and for 6 He at 65 MeV/u in Lanzhou. The very preliminary results for the distinguish of the reaction mechanism are presented and compared to the kinematics calculation. (authors)

  8. Hyperactivity and lack of social discrimination in the adolescent Fmr1 knockout mouse

    DEFF Research Database (Denmark)

    Sørensen, Emilie M; Bertelsen, Freja; Weikop, Pia

    2015-01-01

    The aims of this study were to investigate behaviour relevant to human autism spectrum disorder (ASD) and the fragile X syndrome in adolescent Fmr1 knockout (KO) mice and to evaluate the tissue levels of striatal monoamines. Fmr1 KO mice were evaluated in the open field, marble burying and three...

  9. Myocardial ischemia and reperfusion injury: Studies using transgenic and knockout mice

    NARCIS (Netherlands)

    Jong, W. M. C.; ten Cate, H.; Reitsma, P. H.; de Winter, R. J.

    2005-01-01

    Transgenic and knockout mice are created and used for a large variety of research objectives. This overview describes the (genetically modified) mouse models that have been used to study the development of myocardial ischemia and reperfusion injury. The role of cytokines, chemokines, leukocytes,

  10. A baculovirus alkaline nuclease knockout construct produces fragmented DNA and aberrant capsids

    International Nuclear Information System (INIS)

    Okano, Kazuhiro; Vanarsdall, Adam L.; Rohrmann, George F.

    2007-01-01

    DNA replication of bacmid-derived constructs of the Autographa californica multiple nucleocapsid nucleopolyhedrovirus (AcMNPV) was analyzed by field inversion gel electrophoresis (FIGE) in combination with digestion at a unique Eco81I restriction enzyme site. Three constructs were characterized: a parental bacmid, a bacmid deleted for the alkaline nuclease gene, and a bacmid from which the gp64 gene had been deleted. The latter was employed as a control for comparison with the alkaline nuclease knockout because neither yields infectious virus and their replication is limited to the initially transfected cells. The major difference between DNA replicated by the different constructs was the presence in the alkaline nuclease knockout of high concentrations of relatively small, subgenome length DNA in preparations not treated with Eco81I. Furthermore, upon Eco81I digestion, the alkaline nuclease knockout bacmid also yielded substantially more subgenome size DNA than the other constructs. Electron microscopic examination of cells transfected with the alkaline nuclease knockout indicated that, in addition to a limited number of normal-appearing electron-dense nucleocapsids, numerous aberrant capsid-like structures were observed indicating a defect in nucleocapsid maturation or in a DNA processing step that is necessary for encapsidation. Because of the documented role of the baculovirus alkaline nuclease and its homologs from other viruses in homologous recombination, these data suggest that DNA recombination may play a major role in the production of baculovirus genomes

  11. Serotonin Transporter Knockout Rats Show Improved Strategy Set-Shifting and Reduced Latent Inhibition

    Science.gov (United States)

    Nonkes, Lourens J. P.; van de Vondervoort, Ilse I. G. M.; de Leeuw, Mark J. C.; Wijlaars, Linda P.; Maes, Joseph H. R.; Homberg, Judith R.

    2012-01-01

    Behavioral flexibility is a cognitive process depending on prefrontal areas allowing adaptive responses to environmental changes. Serotonin transporter knockout (5-HTT[superscript -/-]) rodents show improved reversal learning in addition to orbitofrontal cortex changes. Another form of behavioral flexibility, extradimensional strategy set-shifting…

  12. Crucial role of alkaline sphingomyelinase in sphingomyelin digestion: a study on enzyme knockout mice

    DEFF Research Database (Denmark)

    Zhang, Yao; Cheng, Yajun; Hansen, Gert H

    2011-01-01

    Alkaline sphingomyelinase (alk-SMase) hydrolyses sphingomyelin (SM) to ceramide in the gut. To evaluate the physiological importance of the enzyme, we generated alk-SMase knockout (KO) mice by the Cre-recombinase-Locus of X-over P1(Cre-LoxP) system and studied SM digestion. Both wild-type (WT...

  13. Cross sections for one-neutron knock-out from Ca-37 at intermediate energy

    Czech Academy of Sciences Publication Activity Database

    Burger, A.; Azaiez, F.; Algora, A.; Al-Khatib, A.; Bastin, B.; Benzoni, G.; Borcea, R.; Bourgeois, C.; Bringel, P.; Clement, E.; Dalouzy, J.-C.; Dlouhý, Zdeněk; Dombradi, Z.; Drouart, A.; Engelhardt, C.; Franchoo, S.; Fülöp, Zs.; Gorgen, A.; Grévy, S.; Hubel, H.; Ibrahim, F.; Korten, W.; Mrázek, Jaromír; Navin, A.; Rotaru, F.; Chomaz, P. R.; Saint-Laurent, M. G.; Sletten, G.; Sohler, D.; Sorlin, O.; Stanoiu, M.; Stefan, I.; Theisen, C.; Timis, C.; Verney, D.; Williams, S.

    2012-01-01

    Roč. 86, č. 6 (2012), 064609/1-064609/5 ISSN 0556-2813 Institutional support: RVO:61389005 Keywords : nuclear structure * knock-out reactions * shell model Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 3.715, year: 2012 http://prc.aps.org/pdf/PRC/v86/i6/e064609

  14. Behavior training reverses asymmetry in hippocampal transcriptome of the cav3.2 knockout mice.

    Directory of Open Access Journals (Sweden)

    Ni-Chun Chung

    Full Text Available Homozygous Cav3.2 knockout mice, which are defective in the pore-forming subunit of a low voltage activated T-type calcium channel, have been documented to show impaired maintenance of late-phase long-term potentiation (L-LTP and defective retrieval of context-associated fear memory. To investigate the role of Cav3.2 in global gene expression, we performed a microarray transcriptome study on the hippocampi of the Cav3.2-/- mice and their wild-type littermates, either naïve (untrained or trace fear conditioned. We found a significant left-right asymmetric effect on the hippocampal transcriptome caused by the Cav3.2 knockout. Between the naive Cav3.2-/- and the naive wild-type mice, 3522 differentially expressed genes (DEGs were found in the left hippocampus, but only 4 DEGs were found in the right hippocampus. Remarkably, the effect of Cav3.2 knockout was partially reversed by trace fear conditioning. The number of DEGs in the left hippocampus was reduced to 6 in the Cav3.2 knockout mice after trace fear conditioning, compared with the wild-type naïve mice. To our knowledge, these results demonstrate for the first time the asymmetric effects of the Cav3.2 and its partial reversal by behavior training on the hippocampal transcriptome.

  15. Mu-opioid receptor knockout mice show diminished food-anticipatory activity

    NARCIS (Netherlands)

    Kas, Martien J H; van den Bos, Ruud; Baars, Annemarie M; Lubbers, Marianne; Lesscher, Heidi M B; Hillebrand, Jacquelien J G; Schuller, Alwin G; Pintar, John E; Spruijt, Berry M

    We have previously suggested that during or prior to activation of anticipatory behaviour to a coming reward, mu-opioid receptors are activated. To test this hypothesis schedule induced food-anticipatory activity in mu-opioid receptor knockout mice was measured using running wheels. We hypothesized

  16. Histidine decarboxylase knockout mice, a genetic model of Tourette syndrome, show repetitive grooming after induced fear.

    Science.gov (United States)

    Xu, Meiyu; Li, Lina; Ohtsu, Hiroshi; Pittenger, Christopher

    2015-05-19

    Tics, such as are seen in Tourette syndrome (TS), are common and can cause profound morbidity, but they are poorly understood. Tics are potentiated by psychostimulants, stress, and sleep deprivation. Mutations in the gene histidine decarboxylase (Hdc) have been implicated as a rare genetic cause of TS, and Hdc knockout mice have been validated as a genetic model that recapitulates phenomenological and pathophysiological aspects of the disorder. Tic-like stereotypies in this model have not been observed at baseline but emerge after acute challenge with the psychostimulant d-amphetamine. We tested the ability of an acute stressor to stimulate stereotypies in this model, using tone fear conditioning. Hdc knockout mice acquired conditioned fear normally, as manifested by freezing during the presentation of a tone 48h after it had been paired with a shock. During the 30min following tone presentation, knockout mice showed increased grooming. Heterozygotes exhibited normal freezing and intermediate grooming. These data validate a new paradigm for the examination of tic-like stereotypies in animals without pharmacological challenge and enhance the face validity of the Hdc knockout mouse as a pathophysiologically grounded model of tic disorders. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  17. Altered sleep and affect in the neurotensin receptor 1 knockout mouse.

    Science.gov (United States)

    Fitzpatrick, Karrie; Winrow, Christopher J; Gotter, Anthony L; Millstein, Joshua; Arbuzova, Janna; Brunner, Joseph; Kasarskis, Andrew; Vitaterna, Martha H; Renger, John J; Turek, Fred W

    2012-07-01

    Sleep and mood disorders have long been understood to have strong genetic components, and there is considerable comorbidity of sleep abnormalities and mood disorders, suggesting the involvement of common genetic pathways. Here, we examine a candidate gene implicated in the regulation of both sleep and affective behavior using a knockout mouse model. Previously, we identified a quantitative trait locus (QTL) for REM sleep amount, REM sleep bout number, and wake amount in a genetically segregating population of mice. Here, we show that traits mapping to this QTL correlated with an expression QTL for neurotensin receptor 1 (Ntsr1), a receptor for neurotensin, a ligand known to be involved in several psychiatric disorders. We examined sleep as well as behaviors indicative of anxiety and depression in the NTSR1 knockout mouse. NTSR1 knockouts had a lower percentage of sleep time spent in REM sleep in the dark phase and a larger diurnal variation in REM sleep duration than wild types under baseline conditions. Following sleep deprivation, NTSR1 knockouts exhibited more wake and less NREM rebound sleep. NTSR1 knockouts also showed increased anxious and despair behaviors. Here we illustrate a link between expression of the Ntsr1 gene and sleep traits previously associated with a particular QTL. We also demonstrate a relationship between Ntsr1 and anxiety and despair behaviors. Given the considerable evidence that anxiety and depression are closely linked with abnormalities in sleep, the data presented here provide further evidence that neurotensin and Ntsr1 may be a component of a pathway involved in both sleep and mood disorders.

  18. P-glycoprotein interaction with risperidone and 9-OH-risperidone studied in vitro, in knock-out mice and in drug-drug interaction experiments

    DEFF Research Database (Denmark)

    Ejsing, Thomas B.; Pedersen, Anne D.; Linnet, Kristian

    2005-01-01

    P-glycoprotein, risperidone, nortriptyline, cyclosporine A, drug-drug interaction, blood-brain barrier, knock-out mice......P-glycoprotein, risperidone, nortriptyline, cyclosporine A, drug-drug interaction, blood-brain barrier, knock-out mice...

  19. Suppressor of Overexpression of CO 1 Negatively Regulates Dark-Induced Leaf Degreening and Senescence by Directly Repressing Pheophytinase and Other Senescence-Associated Genes in Arabidopsis.

    Science.gov (United States)

    Chen, Junyi; Zhu, Xiaoyu; Ren, Jun; Qiu, Kai; Li, Zhongpeng; Xie, Zuokun; Gao, Jiong; Zhou, Xin; Kuai, Benke

    2017-03-01

    Although the biochemical pathway of chlorophyll (Chl) degradation has been largely elucidated, how Chl is rapidly yet coordinately degraded during leaf senescence remains elusive. Pheophytinase (PPH) is the enzyme for catalyzing the removal of the phytol group from pheophytin a , and PPH expression is significantly induced during leaf senescence. To elucidate the transcriptional regulation of PPH , we used a yeast ( Saccharomyces cerevisiae ) one-hybrid system to screen for its trans-regulators. SUPPRESSOR OF OVEREXPRESSION OF CO 1 (SOC1), a key flowering pathway integrator, was initially identified as one of the putative trans-regulators of PPH After dark treatment, leaves of an SOC1 knockdown mutant ( soc1-6 ) showed an accelerated yellowing phenotype, whereas those of SOC1 -overexpressing lines exhibited a partial stay-green phenotype. SOC1 and PPH expression showed a negative correlation during leaf senescence. Substantially, SOC1 protein could bind specifically to the CArG box of the PPH promoter in vitro and in vivo, and overexpression of SOC1 significantly inhibited the transcriptional activity of the PPH promoter in Arabidopsis ( Arabidopsis thaliana ) protoplasts. Importantly, soc1-6 pph-1 (a PPH knockout mutant) double mutant displayed a stay-green phenotype similar to that of pph-1 during dark treatment. These results demonstrated that SOC1 inhibits Chl degradation via negatively regulating PPH expression. In addition, measurement of the Chl content and the maximum photochemical efficiency of photosystem II of soc1-6 and SOC1-OE leaves after dark treatment suggested that SOC1 also negatively regulates the general senescence process. Seven SENESCENCE-ASSOCIATED GENES ( SAGs ) were thereafter identified as its potential target genes, and NONYELLOWING1 and SAG113 were experimentally confirmed. Together, we reveal that SOC1 represses dark-induced leaf Chl degradation and senescence in general in Arabidopsis. © 2017 American Society of Plant Biologists. All

  20. Highly segmented CVD diamond detectors and high-resolution momentum measurements in knockout reactions; Hochsegmentierte CVD Diamant Detektoren und hochaufloesende Impulsmessungen in Knockout Reaktionen

    Energy Technology Data Exchange (ETDEWEB)

    Schwertel, Sabine

    2009-11-26

    In recent years knockout reactions have proven to be important tools for investigations of the structure of light exotic nuclei. In spring 2006 an experiment was performed with the fragment separator at GSI in Darmstadt to extend this method to medium-mass nuclei with energies of about 400 AMeV. An experiment with a stable and well-known {sup 48}Ca primary beam was performed as a reference. The FRS was set for the reaction {sup 56}Ti{yields}{sup 55}Ti. Because of the high acceptance of the FRS, mother and daughter nuclei of one-neutron knockout reactions in the Sc isotopes {sup 51,52,53,54,55}Sc were also transported with high efficiency. These are investigated in the first part of this thesis. Inclusive cross sections of 77(10) mbarn for one-neutron knockout from {sup 48}Ca and 78(12) mbarn, 99(15) mbarn, 101(15) mbarn, 113(17) mbarn and 72(14) mbarn for knockout from {sup 51,52,53,54,55}Sc, respectively, were measured for the first time. For the Sc isotopes the reduction factors are close to 1. For the one-neutron knockout reactions in {sup 48}Ca and the Sc isotopes, respectively, the momentum distributions could be measured with a relative resolution of 0.17-0.27 %. From the momentum distributions spectroscopic factors of the involved orbitals could be extracted. In the future, further knockout experiments should be performed using the R{sup 3}B setup at FAIR. The available beam intensity will be up to four orders of magnitude higher. As the beam has to be tracked from the dispersive plane of the Super-FRS up to the R{sup 3}B target, radiation hard detectors are needed. In the framework of this thesis extensive measurements were performed at the tandem accelerator in Munich with numerous small (10 x 10 mm{sup 2}) test detectors. Samples using new manufacturing methods were characterized. A dose of some 10{sup 11} ions/mm{sup 2} was determined as a limit for the exposure of the material with heavy ions of high ionisation density. It could be shown that even

  1. Cyclophosphamide-induced myeloid-derived suppressor cell population is immunosuppressive but not identical to myeloid-derived suppressor cells induced by growing TC-1 tumors

    Czech Academy of Sciences Publication Activity Database

    Mikyšková, Romana; Indrová, Marie; Polláková, Veronika; Bieblová, Jana; Šímová, Jana; Reiniš, Milan

    2012-01-01

    Roč. 35, č. 5 (2012), s. 374-384 ISSN 1524-9557 R&D Projects: GA ČR(CZ) GPP301/11/P220; GA ČR GA301/09/1024; GA ČR GA301/07/1410 EU Projects: European Commission(XE) 18933 - CLINIGENE Institutional research plan: CEZ:AV0Z50520514 Institutional support: RVO:68378050 Keywords : myeloid-derived suppressor cells * cyclophosphamide * all-trans-retinoic acid * IL-12 * HPV16 Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.463, year: 2012

  2. Effect of duct shape, Mach number, and lining construction on measured suppressor attenuation and comparison with theory

    Science.gov (United States)

    Olsen, W. A.; Krejsa, E. A.; Coats, J. W.

    1972-01-01

    Noise attenuation was measured for several types of cylindrical suppressors that use a duct lining composed of honeycomb cells covered with a perforated plate. The experimental technique used gave attenuation data that were repeatable and free of noise floors and other sources of error. The suppressor length, the effective acoustic diameter, suppressor shape and flow velocity were varied. The agreement among the attenuation data and two widely used analytical models was generally satisfactory. Changes were also made in the construction of the acoustic lining to measure their effect on attenuation. One of these produced a very broadband muffler.

  3. Modulator of Apoptosis 1 (MOAP-1) Is a Tumor Suppressor Protein Linked to the RASSF1A Protein*

    OpenAIRE

    Law, Jennifer; Salla, Mohamed; Zare, Alaa; Wong, Yoke; Luong, Le; Volodko, Natalia; Svystun, Orysya; Flood, Kayla; Lim, Jonathan; Sung, Miranda; Dyck, Jason R. B.; Tan, Chong Teik; Su, Yu-Chin; Yu, Victor C.; Mackey, John

    2015-01-01

    Modulator of apoptosis 1 (MOAP-1) is a BH3-like protein that plays key roles in cell death or apoptosis. It is an integral partner to the tumor suppressor protein, Ras association domain family 1A (RASSF1A), and functions to activate the Bcl-2 family pro-apoptotic protein Bax. Although RASSF1A is now considered a bona fide tumor suppressor protein, the role of MOAP-1 as a tumor suppressor protein has yet to be determined. In this study, we present several lines of evidence from cancer databas...

  4. Describing the role of Drosophila melanogaster ABC transporters in insecticide biology using CRISPR-Cas9 knockouts.

    Science.gov (United States)

    Denecke, Shane; Fusetto, Roberto; Batterham, Philip

    2017-12-01

    ABC transporters have a well-established role in drug resistance, effluxing xenobiotics from cells and tissues within the organism. More recently, research has been dedicated to understanding the role insect ABC transporters play in insecticide toxicity, but progress in understanding the contribution of specific transporters has been hampered by the lack of functional genetic tools. Here, we report knockouts of three Drosophila melanogaster ABC transporter genes, Mdr49, Mdr50, and Mdr65, that are homologous to the well-studied mammalian ABCB1 (P-glycoprotein). Each knockout mutant was created in the same wild type background and tested against a panel of insecticides representing different chemical classes. Mdr65 knockouts were more susceptible to all neuroactive insecticides tested, but Mdr49 and Mdr50 knockouts showed increased susceptibility or resistance depending on the insecticide used. Mdr65 was chosen for further analysis. Calculation of LC 50 values for the Mdr65 knockout allowed the substrate specificity of this transporter to be examined. No obvious distinguishing structural features were shared among MDR65 substrates. A role for Mdr65 in insecticide transport was confirmed by testing the capacity of the knockout to synergize with the ABC inhibitor verapamil and by measuring the levels of insecticide retained in the body of knockout flies. These data unambiguously establish the influence of ABC transporters on the capacity of wild type D. melanogaster to tolerate insecticide exposure and suggest that both tissue and substrate specificity underpin this capacity. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Characterisation of iunH gene knockout strain from Mycobacterium tuberculosis

    Directory of Open Access Journals (Sweden)

    Anne Drumond Villela

    Full Text Available BACKGROUND Tuberculosis (TB is an infectious disease caused mainly by the bacillus Mycobacterium tuberculosis. The better understanding of important metabolic pathways from M. tuberculosis can contribute to the development of novel therapeutic and prophylactic strategies to combat TB. Nucleoside hydrolase (MtIAGU-NH, encoded by iunH gene (Rv3393, is an enzyme from purine salvage pathway in M. tuberculosis. MtIAGU-NH accepts inosine, adenosine, guanosine, and uridine as substrates, which may point to a pivotal metabolic role. OBJECTIVES Our aim was to construct a M. tuberculosis knockout strain for iunH gene, to evaluate in vitro growth and the effect of iunH deletion in M. tuberculosis in non-activated and activated macrophages models of infection. METHODS A M. tuberculosis knockout strain for iunH gene was obtained by allelic replacement, using pPR27xylE plasmid. The complemented strain was constructed by the transformation of the knockout strain with pNIP40::iunH. MtIAGU-NH expression was analysed by Western blot and LC-MS/MS. In vitro growth was evaluated in Sauton’s medium. Bacterial load of non-activated and interferon-γ activated RAW 264.7 cells infected with knockout strain was compared with wild-type and complemented strains. FINDINGS Western blot and LC-MS/MS validated iunH deletion at protein level. The iunH knockout led to a delay in M. tuberculosis growth kinetics in Sauton’s medium during log phase, but did not affect bases and nucleosides pool in vitro. No significant difference in bacterial load of knockout strain was observed when compared with both wild-type and complemented strains after infection of non-activated and interferon-γ activated RAW 264.7 cells. MAIN CONCLUSION The disruption of iunH gene does not influence M. tuberculosis growth in both non-activated and activated RAW 264.7 cells, which show that iunH gene is not important for macrophage invasion and virulence. Our results indicated that MtIAGU-NH is not a

  6. Noise suppression and crosstalk analysis of on-chip magnetic film-type noise suppressor

    Science.gov (United States)

    Ma, Jingyan; Muroga, Sho; Endo, Yasushi; Hashi, Shuichiro; Naoe, Masayuki; Yokoyama, Hiroo; Hayashi, Yoshiaki; Ishiyama, Kazushi

    2018-05-01

    This paper discusses near field, conduction and crosstalk noise suppression of magnetic films with uniaxial anisotropy on transmission lines for a film-type noise suppressor in the GHz frequency range. The electromagnetic noise suppressions of magnetic films with different permeability and resistivity were measured and simulated with simple microstrip lines. The experimental and simulated results of Co-Zr-Nb and CoPd-CaF2 films agreed with each other. The results indicate that the higher permeability leads to a better near field shielding, and in the frequency range of 2-7 GHz, a higher conduction noise suppression. It also suggests that the higher resistivity results in a better crosstalk suppression in the frequency range below 2 GHz. These results can support the design guidelines of the magnetic film-type noise suppressor used in the next generation IC chip.

  7. Proton cross-talk and losses in the dispersion suppressor regions at the FCC-hh

    CERN Document Server

    AUTHOR|(CDS)2100784; Appleby, Robert Barrie; Krainer, Alexander; Langner, Andy Sven; Abelleira, Jose

    2017-01-01

    Protons that collide at the interaction points of the FCC-hh may contribute to the background in the subsequent detector. Due to the high luminosity of the proton beams this may be of concern. Using DPMJET-III to model 50 TeV proton-proton collisions, tracking studies have been performed with PTC and MERLIN in order to gauge the elastic and inelastic proton cross-talk. High arc losses, particularly in the dispersion suppressor regions, have been revealed. These losses originate mainly from particles with a momentum deviation, either from interaction with a primary collimator in the betatron cleaning insertion, or from the proton-proton collisions. This issue can be mitigated by introducing additional collimators in the dispersion suppressor region. The specific design, lattice integration, and the effect of these collimators on cross-talk is assessed.

  8. Nutrient restriction enhances the proliferative potential of cells lacking the tumor suppressor PTEN in mitotic tissues

    Science.gov (United States)

    Nowak, Katarzyna; Seisenbacher, Gerhard; Hafen, Ernst; Stocker, Hugo

    2013-01-01

    How single cells in a mitotic tissue progressively acquire hallmarks of cancer is poorly understood. We exploited mitotic recombination in developing Drosophila imaginal tissues to analyze the behavior of cells devoid of the tumor suppressor PTEN, a negative regulator of PI3K signaling, under varying nutritional conditions. Cells lacking PTEN strongly overproliferated specifically in nutrient restricted larvae. Although the PTEN mutant cells were sensitive to starvation, they successfully competed with neighboring cells by autonomous and non-autonomous mechanisms distinct from cell competition. The overgrowth was strictly dependent on the activity of the downstream components Akt/PKB and TORC1, and a reduction in amino acid uptake by reducing the levels of the amino acid transporter Slimfast caused clones of PTEN mutant cells to collapse. Our findings demonstrate how limiting nutritional conditions impact on cells lacking the tumor suppressor PTEN to cause hyperplastic overgrowth. DOI: http://dx.doi.org/10.7554/eLife.00380.001 PMID:23853709

  9. System and method for multi-stage bypass, low operating temperature suppressor for automatic weapons

    Science.gov (United States)

    Moss, William C.; Anderson, Andrew T.

    2015-06-09

    The present disclosure relates to a suppressor for use with a weapon. The suppressor may be formed to have a body portion having a bore extending concentric with a bore axis of the weapon barrel. An opening in the bore extends at least substantially circumferentially around the bore. A flow path communicates with the opening and defines a channel for redirecting gasses flowing in the bore out from the bore, through the opening, into a rearward direction in the flow path. The flow path raises a pressure at the opening to generate a Mach disk within the bore at a location approximately coincident with the opening. The Mach disk forms as a virtual baffle to divert at least a portion of the gasses into the opening and into the flow path.

  10. Tumor suppressor WWOX and p53 alterations and drug resistance in glioblastomas

    Directory of Open Access Journals (Sweden)

    Ming-Fu eChiang

    2013-03-01

    Full Text Available Tumor suppressor p53 are frequently mutated in glioblastomas (GBMs and appears to contribute, in part, to resistance to temozolomide and therapeutic drugs. WW domain-containing oxidoreductase WWOX (FOR or WOX1 is a proapoptotic protein and is considered as a tumor suppressor. Loss of WWOX gene expression is frequently seen in malignant cancer cells due to promoter hypermethylation, genetic alterations, and translational blockade. Intriguingly, ectopic expression of wild type WWOX preferentially induces apoptosis in human glioblastoma cells harboring mutant p53. WWOX is known to physically bind and stabilize wild type p53. Here, we provide an overview for the updated knowledge in p53 and WWOX, and postulate a potential scenarios that wild type and mutant p53, or isoforms, modulate the apoptotic function of WWOX. We propose that triggering WWOX activation by therapeutic drugs under p53 functional deficiency is needed to overcome TMZ resistance and induce GBM cell death.

  11. Construction of Mycobacterium tuberculosis cdd knockout and evaluation of invasion and growth in macrophages

    Directory of Open Access Journals (Sweden)

    Anne Drumond Villela

    Full Text Available Cytidine deaminase (MtCDA, encoded by cdd gene (Rv3315c, is the only enzyme identified in nucleotide biosynthesis pathway of Mycobacterium tuberculosis that is able to recycle cytidine and deoxycytidine. An M. tuberculosis knockout strain for cdd gene was obtained by allelic replacement. Evaluation of mRNA expression validated cdd deletion and showed the absence of polar effect. MudPIT LC-MS/MS data indicated thymidine phosphorylase expression was decreased in knockout and complemented strains. The cdd disruption does not affect M. tuberculosis growth both in Mid- dlebrook 7H9 and in RAW 264.7 cells, which indicates that cdd is not important for macrophage invasion and virulence.

  12. Knockout of GAD65 has major impact on synaptic GABA synthesized from astrocyte-derived glutamine

    DEFF Research Database (Denmark)

    Walls, Anne Byriel; Eyjolfsson, Elvar M.; Smeland, Olav B.

    2011-01-01

    γ-Aminobutyric acid (GABA) synthesis from glutamate is catalyzed by glutamate decarboxylase (GAD) of which two isoforms, GAD65 and GAD67, have been identified. The GAD65 has repeatedly been shown to be important during intensified synaptic activity. To specifically elucidate the significance of GAD......65 for maintenance of the highly compartmentalized intracellular and intercellular GABA homeostasis, GAD65 knockout and corresponding wild-type mice were injected with [1-(13)C]glucose and the astrocyte-specific substrate [1,2-(13)C]acetate. Synthesis of GABA from glutamine in the GABAergic synapses...... was further investigated in GAD65 knockout and wild-type mice using [1,2-(13)C]acetate and in some cases γ-vinylGABA (GVG, Vigabatrin), an inhibitor of GABA degradation. A detailed metabolic mapping was obtained by nuclear magnetic resonance (NMR) spectroscopic analysis of tissue extracts of cerebral cortex...

  13. Generation of knockout rabbits using transcription activator-like effector nucleases

    Directory of Open Access Journals (Sweden)

    Yu Wang

    2014-01-01

    Full Text Available Zinc-finger nucleases and transcription activator-like effector nucleases are novel gene-editing platforms contributing to redefine the boundaries of modern biological research. They are composed of a non-specific cleavage domain and a tailor made DNA-binding module, which enables a broad range of genetic modifications by inducing efficient DNA double-strand breaks at desired loci. Among other remarkable uses, these nucleases have been employed to produce gene knockouts in mid-size and large animals, such as rabbits and pigs, respectively. This approach is cost effective, relatively quick, and can produce invaluable models for human disease studies, biotechnology or agricultural purposes. Here we describe a protocol for the efficient generation of knockout rabbits using transcription activator-like effector nucleases, and a perspective of the field.

  14. Alloantigen-specific suppressor T cells are not inhibited by cyclosporin A, but do require IL 2 for activation

    International Nuclear Information System (INIS)

    Bucy, R.P.

    1986-01-01

    Alloantigen-specific suppressor T cells are activated from normal murine spleen cells in mixed lymphocyte reactions (MLR). These T cells are radioresistant and suppress the activation of cytotoxic T lymphocytes (CTL) in second primary MLR cultures. This report demonstrates that cyclosporin A (CsA) blocks the activation of these suppressor cells at a dose of 1 microgram/ml. However, reconstitution of CsA blocked cultures with IL 2 restores the activation of the suppressor T cells, but fails to significantly restore the activation of CTL in these same cultures. This differential activation requirement was used to establish T cell lines that demonstrate enriched suppressor cell activity but depletion of CTL activity. These findings are discussed in terms of the mechanism of action of CsA in these distinct T cell subsets and the relevance to models of allograft unresponsiveness

  15. MicroRNA-34a is a potent tumor suppressor molecule in vivo in neuroblastoma.

    LENUS (Irish Health Repository)

    Tivnan, Amanda

    2011-01-01

    Neuroblastoma is a paediatric cancer which originates from precursor cells of the sympathetic nervous system and accounts for 15% of childhood cancer mortalities. With regards to the role of miRNAs in neuroblastoma, miR-34a, mapping to a chromosome 1p36 region that is commonly deleted, has been found to act as a tumor suppressor through targeting of numerous genes associated with cell proliferation and apoptosis.

  16. Extragenic suppressor mutations in ΔripA disrupt stability and function of LpxA.

    Science.gov (United States)

    Miller, Cheryl N; Steele, Shaun P; Brunton, Jason C; Jenkins, Ronald J; LoVullo, Eric D; Taft-Benz, Sharon A; Romanchuk, Artur; Jones, Corbin D; Dotson, Garry D; Collins, Edward J; Kawula, Thomas H

    2014-12-31

    Francisella tularensis is a Gram-negative bacterium that infects hundreds of species including humans, and has evolved to grow efficiently within a plethora of cell types. RipA is a conserved membrane protein of F. tularensis, which is required for growth inside host cells. As a means to determine RipA function we isolated and mapped independent extragenic suppressor mutants in ∆ripA that restored growth in host cells. Each suppressor mutation mapped to one of two essential genes, lpxA or glmU, which are involved in lipid A synthesis. We repaired the suppressor mutation in lpxA (S102, LpxA T36N) and the mutation in glmU (S103, GlmU E57D), and demonstrated that each mutation was responsible for the suppressor phenotype in their respective strains. We hypothesize that the mutation in S102 altered the stability of LpxA, which can provide a clue to RipA function. LpxA is an UDP-N-acetylglucosamine acyltransferase that catalyzes the transfer of an acyl chain from acyl carrier protein (ACP) to UDP-N-acetylglucosamine (UDP-GlcNAc) to begin lipid A synthesis. LpxA was more abundant in the presence of RipA. Induced expression of lpxA in the ΔripA strain stopped bacterial division. The LpxA T36N S102 protein was less stable and therefore less abundant than wild type LpxA protein. These data suggest RipA functions to modulate lipid A synthesis in F. tularensis as a way to adapt to the host cell environment by interacting with LpxA.

  17. Myeloid-derived suppressor cells restrain Natural Killer cell activity in CVB3 myocarditis

    OpenAIRE

    Holz, Lisa Maria

    2017-01-01

    Murine models of coxsackievirus B3 (CVB3) induced myocarditis (with host specific outcomes), represent different outcome of myocarditis, ranging from virus elimination and complete recovery in resistant C57BL/6J mice to virus persistence and chronic myocarditis in susceptible A.BY/SnJ mice. In previous experiments, we found that Natural Killer cells (NK cells) positively influence the outcome of CVB3 myocarditis in mice. Myeloid-derived suppressor cells (MDSC) are potent inhibitors of the inn...

  18. Generation of two modified mouse alleles of the Hic1 tumor suppressor gene

    Czech Academy of Sciences Publication Activity Database

    Pospíchalová, Vendula; Turečková, Jolana; Fafílek, Bohumil; Vojtěchová, Martina; Krausová, Michaela; Lukáš, Jan; Šloncová, Eva; Takacova, S.; Divoký, V.; Leprince, D.; Plachý, Jiří; Kořínek, Vladimír

    2011-01-01

    Roč. 49, č. 3 (2011), s. 142-151 ISSN 1526-954X R&D Projects: GA ČR(CZ) GA204/07/1567; GA ČR(CZ) GD204/09/H058 Institutional research plan: CEZ:AV0Z50520514 Keywords : Hypermethylated In Cancer 1 * Hic1 tumor suppressor * gene targeting Subject RIV: EB - Gene tics ; Molecular Biology Impact factor: 2.527, year: 2011

  19. Three distinct suppressors of RNA silencing encoded by a 20-kb viral RNA genome

    Science.gov (United States)

    Lu, Rui; Folimonov, Alexey; Shintaku, Michael; Li, Wan-Xiang; Falk, Bryce W.; Dawson, William O.; Ding, Shou-Wei

    2004-11-01

    Viral infection in both plant and invertebrate hosts requires a virus-encoded function to block the RNA silencing antiviral defense. Here, we report the identification and characterization of three distinct suppressors of RNA silencing encoded by the 20-kb plus-strand RNA genome of citrus tristeza virus (CTV). When introduced by genetic crosses into plants carrying a silencing transgene, both p20 and p23, but not coat protein (CP), restored expression of the transgene. Although none of the CTV proteins prevented DNA methylation of the transgene, export of the silencing signal (capable of mediating intercellular silencing spread) was detected only from the F1 plants expressing p23 and not from the CP- or p20-expressing F1 plants, demonstrating suppression of intercellular silencing by CP and p20 but not by p23. Thus, intracellular and intercellular silencing are each targeted by a CTV protein, whereas the third, p20, inhibits silencing at both levels. Notably, CP suppresses intercellular silencing without interfering with intracellular silencing. The novel property of CP suggests a mechanism distinct to p20 and all of the other viral suppressors known to interfere with intercellular silencing and that this class of viral suppressors may not be consistently identified by Agrobacterium coinfiltration because it also induces RNA silencing against the infiltrated suppressor transgene. Our analyses reveal a sophisticated viral counter-defense strategy that targets the silencing antiviral pathway at multiple steps and may be essential for protecting CTV with such a large RNA genome from antiviral silencing in the perennial tree host. RNA interference | citrus tristeza virus | virus synergy | antiviral immunity

  20. High-density zero suppressor and encoder VME board using field programmable gate array

    International Nuclear Information System (INIS)

    Aloisio, A.; Cevenini, F.; Patricelli, S.; INFN, Napoli; Parascandolo, P.

    1994-01-01

    The authors describe a 96 bit zero-suppressor and encoder VME board designed for the RPC trigger system of the L3 Forward/Backward Muon detector at CERN. Running at 20 MHz clock frequency, the board processes the elementary 96 bit wide detector pattern in less than one microsecond, storing hit addresses in a FIFO array. Details of the board architecture--based on seven XILINX XC3020 LCAs--are presented and simulation and preliminary test results are briefly reported

  1. Generation of two modified mouse alleles of the Hic1 tumor suppressor gene

    Czech Academy of Sciences Publication Activity Database

    Pospíchalová, Vendula; Turečková, Jolana; Fafílek, Bohumil; Vojtěchová, Martina; Krausová, Michaela; Lukáš, Jan; Šloncová, Eva; Takacova, S.; Divoký, V.; Leprince, D.; Plachý, Jiří; Kořínek, Vladimír

    2011-01-01

    Roč. 49, č. 3 (2011), s. 142-151 ISSN 1526-954X R&D Projects: GA ČR(CZ) GA204/07/1567; GA ČR(CZ) GD204/09/H058 Institutional research plan: CEZ:AV0Z50520514 Keywords : Hypermethylated In Cancer 1 * Hic1 tumor suppressor * gene targeting Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.527, year: 2011

  2. Clinical Impact of the Immunome in Lymphoid Malignancies: The Role of Myeloid-Derived Suppressor Cells

    Science.gov (United States)

    Vetro, Calogero; Romano, Alessandra; Ancora, Flavia; Coppolino, Francesco; Brundo, Maria V.; Raccuia, Salvatore A.; Puglisi, Fabrizio; Tibullo, Daniele; La Cava, Piera; Giallongo, Cesarina; Parrinello, Nunziatina L.

    2015-01-01

    The better definition of the mutual sustainment between neoplastic cells and immune system has been translated from the bench to the bedside acquiring value as prognostic factor. Additionally, it represents a promising tool for improving therapeutic strategies. In this context, myeloid-derived suppressor cells (MDSCs) have gained a central role in tumor developing with consequent therapeutic implications. In this review, we will focus on the biological and clinical impact of the study of MDSCs in the settings of lymphoid malignancies. PMID:26052505

  3. The p53 tumour suppressor gene and the tobacco industry: research, debate, and conflict of interest

    OpenAIRE

    Bitton, A; Neuman, M D; Barnoya, J; Glantz, Stanton A. Ph.D.

    2005-01-01

    Mutations in the p53 tumour suppressor gene lead to uncontrolled cell division and are found in over 50% of all human tumours, including 60% of lung cancers. Research published in 1996 by Denissenko and colleagues demonstrated patterned in-vitro mutagenic effects on p53 of benzo[a]pyrene, a carcinogen present in tobacco smoke. We investigated the tobacco industry's response to p53 research linking smoking to cancer. We searched online tobacco document archives, including the Legacy Tobacco Do...

  4. Electrochemical sensing of tumor suppressor protein p53-deoxyribonucleic acid complex stability at an electrified interface

    Czech Academy of Sciences Publication Activity Database

    Paleček, Emil; Černocká, Hana; Ostatná, Veronika; Navrátilová, Lucie; Brázdová, Marie

    2014-01-01

    Roč. 828, MAY2014 (2014), s. 1-8 ISSN 0003-2670 R&D Projects: GA ČR(CZ) GAP301/11/2055; GA ČR(CZ) GA13-00956S; GA ČR(CZ) GA13-36108S Institutional support: RVO:68081707 Keywords : Deoxyribonucleic acid-protein binding * Tumor suppressor protein p53 * Electrochemical sensing Subject RIV: BO - Biophysics Impact factor: 4.513, year: 2014

  5. Transducer of ERBB2.1 (TOB1 as a Tumor Suppressor: A Mechanistic Perspective

    Directory of Open Access Journals (Sweden)

    Hun Seok Lee

    2015-12-01

    Full Text Available Transducer of ERBB2.1 (TOB1 is a tumor-suppressor protein, which functions as a negative regulator of the receptor tyrosine-kinase ERBB2. As most of the other tumor suppressor proteins, TOB1 is inactivated in many human cancers. Homozygous deletion of TOB1 in mice is reported to be responsible for cancer development in the lung, liver, and lymph node, whereas the ectopic overexpression of TOB1 shows anti-proliferation, and a decrease in the migration and invasion abilities on cancer cells. Biochemical studies revealed that the anti-proliferative activity of TOB1 involves mRNA deadenylation and is associated with the reduction of both cyclin D1 and cyclin-dependent kinase (CDK expressions and the induction of CDK inhibitors. Moreover, TOB1 interacts with an oncogenic signaling mediator, β-catenin, and inhibits β-catenin-regulated gene transcription. TOB1 antagonizes the v-akt murine thymoma viral oncogene (AKT signaling and induces cancer cell apoptosis by activating BCL2-associated X (BAX protein and inhibiting the BCL-2 and BCL-XL expressions. The tumor-specific overexpression of TOB1 results in the activation of other tumor suppressor proteins, such as mothers against decapentaplegic homolog 4 (SMAD4 and phosphatase and tensin homolog-10 (PTEN, and blocks tumor progression. TOB1-overexpressing cancer cells have limited potential of growing as xenograft tumors in nude mice upon subcutaneous implantation. This review addresses the molecular basis of TOB1 tumor suppressor function with special emphasis on its regulation of intracellular signaling pathways.

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

    Directory of Open Access Journals (Sweden)

    Anna Osiak

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

  7. Impairments in the initiation of maternal behavior in oxytocin receptor knockout mice.

    Directory of Open Access Journals (Sweden)

    Megan E Rich

    Full Text Available Oxytocin (Oxt acting through its single receptor subtype, the Oxtr, is important for the coordination of physiology and behavior associated with parturition and maternal care. Knockout mouse models have been helpful in exploring the contributions of Oxt to maternal behavior, including total body Oxt knockout (Oxt -/- mice, forebrain conditional Oxtr knockout (Oxtr FB/FB mice, and total body Oxtr knockout (Oxtr -/- mice. Since Oxtr -/- mice are unable to lactate, maternal behavior has only been examined in virgin females, or in dams within a few hours of parturition, and there have been no studies that have examined their anxiety-like and depression-like behavior following parturition. To improve our understanding of how the absence of Oxt signaling affects maternal behavior, mood and anxiety, we designed a study using Oxtr -/- mice that separated nursing behavior from other aspects of maternal care, such as licking and grooming by thelectomizing (i.e. removing the nipples of Oxtr +/+ mice and sham-thelectomizing Oxtr -/- mice, and pairing both genotypes with a wet nurse. We then measured pup abandonment, maternal behavior, and postpartum anxiety-like and depression-like behaviors. We hypothesized that genetic disruption of the Oxtr would impact maternal care, mood and anxiety. Specifically, we predicted that Oxtr -/- dams would have impaired maternal care and increased anxiety-like and depression-like behaviors in the postpartum period. We found that Oxtr -/- dams had significantly higher levels of pup abandonment compared to controls, which is consistent with previous work in Oxtr FB/FB mice. Interestingly, Oxtr -/- dams that initiated maternal care did not differ from wildtype controls in measures of maternal behavior. We also did not find any evidence of altered anxiety-like or depressive-like behavior in the postpartum period of Oxtr -/- dams. Thus, our data suggest that Oxt lowers the threshold for the initiation of maternal behavior.

  8. Memory Impairment in Estrogen Receptor ? Knockout Mice Through Accumulation of Amyloid-? Peptides

    OpenAIRE

    Hwang, Chul Ju; Yun, Hyung-Mun; Park, Kyung-Ran; Song, Ju Kyung; Seo, Hyun Ok; Hyun, Byung Kook; Choi, Dong Young; Yoo, Hwan-Soo; Oh, Ki-Wan; Hwang, Dae Yeun; Han, Sang-Bae; Hong, Jin Tae

    2014-01-01

    Estrogen has been known to reduce the development of Alzheimer?s disease (AD). However, exact mechanisms are not clear. We investigated whether estrogen can increase amyloid-beta (A?) degradation and affects A?-induced memory impairment in an estrogen deficiency model. Estrogen receptor alpha (ER?) knockout mice and wild-type mice were intracerebroventricular (ICV) infused with A? (300?pmol) for 2?weeks. Cognitive function was then assessed by the Morris water maze test and passive avoidance ...

  9. [Propagation of prdm1 gene knockout mouse and its genotype identification].

    Science.gov (United States)

    Lu, Xiao-Yun; Chen, Chong; Pan, Xiu-Ying; Zeng, Ling-Yu; Li, Zhen-Yu; Song, Xu-Guang; Xu, Kai-Lin

    2012-08-01

    This study was aimed to propagate and identify the prdm1 gene-knockout mice, so as to lay the foundation for studying Blimp-1 protein. Two kinds of transgenic homozygous mice with B6.prdm1(flox/flox) and B6.Lck-Cre were feed and propagated; after successful propagating, the first passage mice were obtained; after the first passage mice were copulated once again, the genotypes were obtained as follows: B6. prdm1(wild/wild). Lck-Cre, B6. prdm1(wild/wild), B6.prdm1(flox/flox). Lck-Cre, B6.prdm1(flox/wild). Lck-Cre, B6.prdm1(flox/flox), B6. prdm1(flox/wild). The genomic DNA of second passage mice was extracted, the Cre and loxp gene fragments were amplified by PCR, then the size of Cre and loxp genomic DNA were detected by agarose gel electrophoresis. The mice with B6.prdm1(flow/flox). Lek-Cre were used as conditionally prdm1-knockout mice, B6.prdm1(flox/wild). Lck-Cre mice, B6.prdm1(flox/flox) and B6 mice were used as controls. The spleen T lymphocytes and B lymphocytes were sorted by using magnetic beads, the blimp-1 target protein was identified by Western blot. The results showed that the two transgenic homozygous mice had the ability to reproduce, and the separation ratio of second passage mice generated from propagation of their offspring cach other meet Mendelian laws, and the prdm1 gene-knockout mice also could successfully obtained. It is concluded that the application of Cre-loxp system may successfully obtain plentiful prdm1 gene-knockout mice.

  10. Dual gene activation and knockout screen reveals directional dependencies in genetic networks. | Office of Cancer Genomics

    Science.gov (United States)

    Understanding the direction of information flow is essential for characterizing how genetic networks affect phenotypes. However, methods to find genetic interactions largely fail to reveal directional dependencies. We combine two orthogonal Cas9 proteins from Streptococcus pyogenes and Staphylococcus aureus to carry out a dual screen in which one gene is activated while a second gene is deleted in the same cell. We analyze the quantitative effects of activation and knockout to calculate genetic interaction and directionality scores for each gene pair.

  11. Fetal growth retardation and lack of hypotaurine in ezrin knockout mice.

    Directory of Open Access Journals (Sweden)

    Tomohiro Nishimura

    Full Text Available Ezrin is a membrane-associated cytoplasmic protein that serves to link cell-membrane proteins with the actin-based cytoskeleton, and also plays a role in regulation of the functional activities of some transmembrane proteins. It is expressed in placental trophoblasts. We hypothesized that placental ezrin is involved in the supply of nutrients from mother to fetus, thereby influencing fetal growth. The aim of this study was firstly to clarify the effect of ezrin on fetal growth and secondly to determine whether knockout of ezrin is associated with decreased concentrations of serum and placental nutrients. Ezrin knockout mice (Ez(-/- were confirmed to exhibit fetal growth retardation. Metabolome analysis of fetal serum and placental extract of ezrin knockout mice by means of capillary electrophoresis-time-of-flight mass spectrometry revealed a markedly decreased concentration of hypotaurine, a precursor of taurine. However, placental levels of cysteine and cysteine sulfinic acid (precursors of hypotaurine and taurine were not affected. Lack of hypotaurine in Ez(-/- mice was confirmed by liquid chromatography with tandem mass spectrometry. Administration of hypotaurine to heterogenous dams significantly decreased the placenta-to-maternal plasma ratio of hypotaurine in wild-type fetuses but only slightly decreased it in ezrin knockout fetuses, indicating that the uptake of hypotaurine from mother to placenta is saturable and that disruption of ezrin impairs the uptake of hypotaurine by placental trophoblasts. These results indicate that ezrin is required for uptake of hypotaurine from maternal serum by placental trophoblasts, and plays an important role in fetal growth.

  12. Effects of ptb knockout on butyric acid fermentation by Clostridium tyrobutyricum.

    Science.gov (United States)

    Zhang, Yali; Yu, Mingrui; Yang, Shang-Tian

    2012-01-01

    Clostridium tyrobutyricum ATCC 25755 is an anaerobic, rod-shaped, gram-positive bacterium that produces butyrate, acetate, hydrogen, and carbon dioxide from various saccharides, including glucose and xylose. Phosphotransbutyrylase (PTB) is a key enzyme in the butyric acid synthesis pathway. In this work, effects of ptb knockout by homologous recombination on metabolic flux and product distribution were investigated. When compared with the wild type, the activities of PTB and butyrate kinase in ptb knockout mutant decreased 76 and 42%, respectively; meanwhile, phosphotransacetylase and acetate kinase increased 7 and 29%, respectively. However, ptb knockout did not significantly reduce butyric acid production from glucose or xylose in batch fermentations. Instead, it increased acetic acid and hydrogen production 33.3-53.8% and ≈ 11%, respectively. Thus, the ptb knockout did increase the carbon flux toward acetate synthesis, resulting in a significant decrease (28-35% reduction) in the butyrate/acetate ratio in ptb mutant fermentations. In addition, the mutant displayed a higher specific growth rate (0.20 h(-1) vs. 0.15 h(-1) on glucose and 0.14 h(-1) vs. 0.10 h(-1) on xylose) and tolerance to butyric acid. Consequently, batch fermentation with the mutant gave higher fermentation rate and productivities (26-48% increase for butyrate, 81-100% increase for acetate, and 38-46% increase for hydrogen). This mutant thus can be used more efficiently than the parental strain in fermentations to produce butyrate, acetate, and hydrogen from glucose and xylose. Copyright © 2011 American Institute of Chemical Engineers (AIChE).

  13. SERPINB5 and AKAP12 -- Expression and promoter methylation of metastasis suppressor genes in pancreatic ductal adenocarcinoma

    Directory of Open Access Journals (Sweden)

    Haier Joerg

    2010-10-01

    Full Text Available Abstract Background Early metastasis and infiltration are survival limiting characteristics of pancreatic ductal adenocarcinoma (PDAC. Thus, PDAC is likely to harbor alterations in metastasis suppressor genes that may provide novel diagnostic and therapeutic opportunities. This study investigates a panel of metastasis suppressor genes in correlation to PDAC phenotype and examines promoter methylation for regulatory influence on metastasis suppressor gene expression and for its potential as a diagnostic tool. Methods Metastatic and invasive potential of 16 PDAC cell lines were quantified in an orthotopic mouse model and mRNA expression of 11 metastasis suppressor genes determined by quantitative RT-PCR. Analysis for promoter methylation was performed using methylation specific PCR and bisulfite sequencing PCR. Protein expression was determined by Western blot. Results In general, higher metastasis suppressor gene mRNA expression was not consistent with less aggressive phenotypes of PDAC. Instead, mRNA overexpression of several metastasis suppressor genes was found in PDAC cell lines vs. normal pancreatic RNA. Of the investigated metastasis suppressor genes, only higher AKAP12 mRNA expression was correlated with decreased metastasis (P SERPINB5 mRNA expression was correlated with increased metastasis scores (P SERPINB5 methylation was associated with loss of mRNA and protein expression (P SERPINB5 methylation was also directly correlated to decreased metastasis scores (P Conclusions AKAP12 mRNA expression was correlated to attenuated invasive and metastatic potential and may be associated with less aggressive phenotypes of PDAC while no such evidence was obtained for the remaining metastasis suppressor genes. Increased SERPINB5 mRNA expression was correlated to increased metastasis and mRNA expression was regulated by methylation. Thus, SERPINB5 methylation was directly correlated to metastasis scores and may provide a diagnostic tool for PDAC.

  14. KLF10, transforming growth factor-β-inducible early gene 1, acts as a tumor suppressor

    International Nuclear Information System (INIS)

    Song, Ki-Duk; Kim, Duk-Jung; Lee, Jong Eun; Yun, Cheol-Heui; Lee, Woon Kyu

    2012-01-01

    Highlights: ► KLF10 −/− mice exhibited accelerated papilloma development after DMBA/TPA treatment. ► KLF10 −/− keratinocytes showed increased proliferation and apoptosis. ► KLF10 −/− MEFs yielded more colonies than wild-type one with H-Ras transfection. ► KLF10 dose-dependently activated p21 WAF1/CIP1 transcription. ► KLF10 is a tumor suppressor and that it targets p21 WAF1/CIP1 transcription. -- Abstract: Krüppel-like factor 10 (KLF10) has been suggested to be a putative tumor suppressor. In the present study, we generated KLF10 deficient mice to explore this hypothesis in vivo. KLF10 deficient mice exhibited increased predisposition to skin tumorigenesis and markedly accelerated papilloma development after DMBA/TPA treatment. On the other hand, KLF10 deficient keratinocytes showed increased proliferation and apoptosis. In colony formation assays after oncogenic H-Ras transfection, KLF10 deficient mouse embryonic fibroblasts (MEFs) yielded more colonies than wild-type MEFs. Furthermore, KLF10 dose-dependently activated p21 WAF1/CIP1 transcription, which was independent of p53 and Sp1 binding sites in p21 WAF1/CIP1 promoter. This study demonstrates that KLF10 is a tumor suppressor and that it targets p21 WAF1/CIP1 transcription.

  15. CMTM5 exhibits tumor suppressor activity through promoter methylation in oral squamous cell carcinoma

    International Nuclear Information System (INIS)

    Zhang, Heyu; Nan, Xu; Li, Xuefen; Chen, Yan; Zhang, Jianyun; Sun, Lisha; Han, Wenlin; Li, Tiejun

    2014-01-01

    Highlights: • Down-regulation of CMTM5 expression in OSCC tissues was found. • The promoter methylation status of CMTM5 was measured. • CMTM5-v1 inhibited cell proliferation and migration and induced apoptosis. • CMTM5 might act as a putative tumor suppressor gene in OSCC. - Abstract: Oral squamous cell carcinoma (OSCC) is one of the most common types of malignancies in the head and neck region. CKLF-like MARVEL transmembrane domain-containing member 5 (CMTM5) has been recently implicated as a tumor suppressor gene in several cancer types. Herein, we examined the expression and function of CMTM5 in oral squamous cell carcinoma. CMTM5 was down-regulated in oral squamous cell lines and tumor samples from patients with promoter methylation. Treatment with the demethylating agent 5-aza-2′-deoxycytidine restored CMTM5 expression. In the OSCC cell lines CAL27 and GNM, the ectopic expression of CMTM5-v1 strongly inhibited cell proliferation and migration and induced apoptosis. In addition, CMTM5-v1 inhibited tumor formation in vivo. Therefore, CMTM5 might act as a putative tumor suppressor gene through promoter methylation in oral squamous cell carcinoma

  16. CMTM5 exhibits tumor suppressor activity through promoter methylation in oral squamous cell carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Heyu [Central Laboratory, Peking University School of Stomatology, Beijing (China); Nan, Xu [Center for Human Disease Genomics, Department of Immunology, Key Laboratory of Medical Immunology, Ministry of Health, School of Basic Medical Sciences, Peking University, Beijing (China); Li, Xuefen [Central Laboratory, Peking University School of Stomatology, Beijing (China); Chen, Yan; Zhang, Jianyun [Department of Oral Pathology, Peking University School of Stomatology, Beijing (China); Sun, Lisha [Central Laboratory, Peking University School of Stomatology, Beijing (China); Han, Wenlin [Center for Human Disease Genomics, Department of Immunology, Key Laboratory of Medical Immunology, Ministry of Health, School of Basic Medical Sciences, Peking University, Beijing (China); Li, Tiejun, E-mail: litiejun22@vip.sina.com [Department of Oral Pathology, Peking University School of Stomatology, Beijing (China)

    2014-05-02

    Highlights: • Down-regulation of CMTM5 expression in OSCC tissues was found. • The promoter methylation status of CMTM5 was measured. • CMTM5-v1 inhibited cell proliferation and migration and induced apoptosis. • CMTM5 might act as a putative tumor suppressor gene in OSCC. - Abstract: Oral squamous cell carcinoma (OSCC) is one of the most common types of malignancies in the head and neck region. CKLF-like MARVEL transmembrane domain-containing member 5 (CMTM5) has been recently implicated as a tumor suppressor gene in several cancer types. Herein, we examined the expression and function of CMTM5 in oral squamous cell carcinoma. CMTM5 was down-regulated in oral squamous cell lines and tumor samples from patients with promoter methylation. Treatment with the demethylating agent 5-aza-2′-deoxycytidine restored CMTM5 expression. In the OSCC cell lines CAL27 and GNM, the ectopic expression of CMTM5-v1 strongly inhibited cell proliferation and migration and induced apoptosis. In addition, CMTM5-v1 inhibited tumor formation in vivo. Therefore, CMTM5 might act as a putative tumor suppressor gene through promoter methylation in oral squamous cell carcinoma.

  17. Macrophages, Inflammation, and Tumor Suppressors: ARF, a New Player in the Game

    Directory of Open Access Journals (Sweden)

    Paqui G. Través

    2012-01-01

    Full Text Available The interaction between tumor progression and innate immune system has been well established in the last years. Indeed, several lines of clinical evidence indicate that immune cells such as tumor-associated macrophages (TAMs interact with tumor cells, favoring growth, angiogenesis, and metastasis of a variety of cancers. In most tumors, TAMs show properties of an alternative polarization phenotype (M2 characterized by the expression of a series of chemokines, cytokines, and proteases that promote immunosuppression, tumor proliferation, and spreading of the cancer cells. Tumor suppressor genes have been traditionally linked to the regulation of cancer progression; however, a growing body of evidence indicates that these genes also play essential roles in the regulation of innate immunity pathways through molecular mechanisms that are still poorly understood. In this paper, we provide an overview of the immunobiology of TAMs as well as what is known about tumor suppressors in the context of immune responses. Recent advances regarding the role of the tumor suppressor ARF as a regulator of inflammation and macrophage polarization are also reviewed.

  18. Mutational hotspots in the TP53 gene and, possibly, other tumor suppressors evolve by positive selection

    Directory of Open Access Journals (Sweden)

    Koonin Eugene V

    2006-01-01

    Full Text Available Abstract Background The mutation spectra of the TP53 gene and other tumor suppressors contain multiple hotspots, i.e., sites of non-random, frequent mutation in tumors and/or the germline. The origin of the hotspots remains unclear, the general view being that they represent highly mutable nucleotide contexts which likely reflect effects of different endogenous and exogenous factors shaping the mutation process in specific tissues. The origin of hotspots is of major importance because it has been suggested that mutable contexts could be used to infer mechanisms of mutagenesis contributing to tumorigenesis. Results Here we apply three independent tests, accounting for non-uniform base compositions in synonymous and non-synonymous sites, to test whether the hotspots emerge via selection or due to mutational bias. All three tests consistently indicate that the hotspots in the TP53 gene evolve, primarily, via positive selection. The results were robust to the elimination of the highly mutable CpG dinucleotides. By contrast, only one, the least conservative test reveals the signature of positive selection in BRCA1, BRCA2, and p16. Elucidation of the origin of the hotspots in these genes requires more data on somatic mutations in tumors. Conclusion The results of this analysis seem to indicate that positive selection for gain-of-function in tumor suppressor genes is an important aspect of tumorigenesis, blurring the distinction between tumor suppressors and oncogenes. Reviewers This article was reviewed by Sandor Pongor, Christopher Lee and Mikhail Blagosklonny.

  19. Specificity of a Rust Resistance Suppressor on 7DL in the Spring Wheat Cultivar Canthatch.

    Science.gov (United States)

    Talajoor, Mina; Jin, Yue; Wan, Anmin; Chen, Xianming; Bhavani, Sridhar; Tabe, Linda; Lagudah, Evans; Huang, Li

    2015-04-01

    The spring wheat 'Canthatch' has been shown to suppress stem rust resistance genes in the background due to the presence of a suppressor gene located on the long arm of chromosome 7D. However, it is unclear whether the suppressor also suppresses resistance genes against leaf rust and stripe rust. In this study, we investigated the specificity of the resistance suppression. To determine whether the suppression is genome origin specific, chromosome location specific, or rust species or race specific, we introduced 11 known rust resistance genes into the Canthatch background, including resistance to leaf, stripe, or stem rusts, originating from A, B, or D genomes and located on different chromosome homologous groups. F1 plants of each cross were tested with the corresponding rust race, and the infection types were scored and compared with the parents. Our results show that the Canthatch 7DL suppressor only suppressed stem rust resistance genes derived from either the A or B genome, and the pattern of the suppression is gene specific and independent of chromosomal location.

  20. RASSF10 is epigenetically silenced and functions as a tumor suppressor in gastric cancer

    Energy Technology Data Exchange (ETDEWEB)

    Wei, Ziran [Department of General Surgery, Shanghai Changzheng Hospital, Second Military Medical University, Shanghai (China); Chen, Xia [Urology Department, Minhang District Central Hospital, Shanghai (China); Chen, Ji; Wang, Weimin [Department of General Surgery, Shanghai Changzheng Hospital, Second Military Medical University, Shanghai (China); Xu, Xudong [Urology Department, Minhang District Central Hospital, Shanghai (China); Cai, Qingping, E-mail: qingping_caicz@163.com [Department of General Surgery, Shanghai Changzheng Hospital, Second Military Medical University, Shanghai (China)

    2013-03-22

    Highlights: ► Epigenetic silencing of RASSF10 gene expression in GC cells. ► RASSF10 overexpression inhibits cell growth in vitro and in vivo. ► RASSF10 induces apoptosis in GC cells. ► RASSF10 inhibits Wnt/β-catenin signaling pathway. -- Abstract: Ras association domain family (RASSF) proteins are encoded by several tumor suppressor genes that are frequently silenced in human cancers. In this study, we investigated RASSF10 as a target of epigenetic inactivation and examined its functions as a tumor suppressor in gastric cancer. RASSF10 was silenced in six out of eight gastric cancer cell lines. Loss or downregulation of RASSF10 expression was associated with promoter hypermethylation, and could be restored by a demethylating agent. Overexpression of RASSF10 in gastric cancer cell lines (JRST, BGC823) suppressed cell growth and colony formation, and induced apoptosis, whereas RASSF10 depletion promoted cell growth. In xenograft animal experiments, RASSF10 overexpression effectively repressed tumor growth. Mechanistic investigations revealed that RASSF10 inhibited tumor growth by blocking activation of β-catenin and its downstream targets including c-Myc, cyclinD1, cyclinE1, peroxisome proliferator-activated receptor δ, transcription factor 4, transcription factor 1 and CD44. In conclusion, the results of this study provide insight into the role of RASSF10 as a novel functional tumor suppressor in gastric cancer through inhibition of the Wnt/β-catenin signaling pathway.

  1. The Ras effector RASSF2 is a novel tumor-suppressor gene in human colorectal cancer.

    Science.gov (United States)

    Akino, Kimishige; Toyota, Minoru; Suzuki, Hiromu; Mita, Hiroaki; Sasaki, Yasushi; Ohe-Toyota, Mutsumi; Issa, Jean-Pierre J; Hinoda, Yuji; Imai, Kohzoh; Tokino, Takashi

    2005-07-01

    Activation of Ras signaling is a hallmark of colorectal cancer (CRC), but the roles of negative regulators of Ras are not fully understood. Our aim was to address that question by surveying genetic and epigenetic alterations of Ras-Ras effector genes in CRC cells. The expression and methylation status of 6 RASSF family genes were examined using RT-PCR and bisulfite PCR in CRC cell lines and in primary CRCs and colorectal adenomas. Colony formation assays and flow cytometry were used to assess the tumor suppressor activities of RASSF1 and RASSF2. Immunofluorescence microscopy was used to determine the effect of altered RASSF2 expression on cell morphology. Mutations of K- ras , BRAF, and p53 were identified using single-strand conformation analysis and direct sequencing. Aberrant methylation and histone deacetylation of RASSF2 was associated with the gene's silencing in CRC. The activities of RASSF2, which were distinct from those of RASSF1, included induction of morphologic changes and apoptosis; moreover, its ability to prevent cell transformation suggests that RASSF2 acts as a tumor suppressor in CRC. Primary CRCs that showed K- ras /BRAF mutations also frequently showed RASSF2 methylation, and inactivation of RASSF2 enhanced K- ras -induced oncogenic transformation. RASSF2 methylation was also frequently identified in colorectal adenomas. RASSF2 is a novel tumor suppressor gene that regulates Ras signaling and plays a pivotal role in the early stages of colorectal tumorigenesis.

  2. Acute secondhand smoke-induced pulmonary inflammation is diminished in RAGE knockout mice.

    Science.gov (United States)

    Wood, Tyler T; Winden, Duane R; Marlor, Derek R; Wright, Alex J; Jones, Cameron M; Chavarria, Michael; Rogers, Geraldine D; Reynolds, Paul R

    2014-11-15

    The receptor for advanced glycation end-products (RAGE) has increasingly been demonstrated to be an important modulator of inflammation in cases of pulmonary disease. Published reports involving tobacco smoke exposure have demonstrated increased expression of RAGE, its participation in proinflammatory signaling, and its role in irreversible pulmonary remodeling. The current research evaluated the in vivo effects of short-term secondhand smoke (SHS) exposure in RAGE knockout and control mice compared with identical animals exposed to room air only. Quantitative PCR, immunoblotting, and immunohistochemistry revealed elevated RAGE expression in controls after 4 wk of SHS exposure and an anticipated absence of RAGE expression in RAGE knockout mice regardless of smoke exposure. Ras activation, NF-κB activity, and cytokine elaboration were assessed to characterize the molecular basis of SHS-induced inflammation in the mouse lung. Furthermore, bronchoalveolar lavage fluid was procured from RAGE knockout and control animals for the assessment of inflammatory cells and molecules. As a general theme, inflammation coincident with leukocyte recruitment was induced by SHS exposure and significantly influenced by the availability of RAGE. These data reveal captivating information suggesting a role for RAGE signaling in lungs exposed to SHS. However, ongoing research is still warranted to fully explain roles for RAGE and other receptors in cells coping with involuntary smoke exposure for prolonged periods of time. Copyright © 2014 the American Physiological Society.

  3. Impact of temporal variation on design and analysis of mouse knockout phenotyping studies.

    Directory of Open Access Journals (Sweden)

    Natasha A Karp

    Full Text Available A significant challenge facing high-throughput phenotyping of in-vivo knockout mice is ensuring phenotype calls are robust and reliable. Central to this problem is selecting an appropriate statistical analysis that models both the experimental design (the workflow and the way control mice are selected for comparison with knockout animals and the sources of variation. Recently we proposed a mixed model suitable for small batch-oriented studies, where controls are not phenotyped concurrently with mutants. Here we evaluate this method both for its sensitivity to detect phenotypic effects and to control false positives, across a range of workflows used at mouse phenotyping centers. We found the sensitivity and control of false positives depend on the workflow. We show that the phenotypes in control mice fluctuate unexpectedly between batches and this can cause the false positive rate of phenotype calls to be inflated when only a small number of batches are tested, when the effect of knockout becomes confounded with temporal fluctuations in control mice. This effect was observed in both behavioural and physiological assays. Based on this analysis, we recommend two approaches (workflow and accompanying control strategy and associated analyses, which would be robust, for use in high-throughput phenotyping pipelines. Our results show the importance in modelling all sources of variability in high-throughput phenotyping studies.

  4. Proximal gut mucosal epithelial homeostasis in aged IL-1 type I receptor knockout mice after starvation.

    Science.gov (United States)

    Song, Juquan; Wolf, Steven E; Wu, Xiao-Wu; Finnerty, Celeste C; Herndon, David N; Jeschke, Marc G

    2011-08-01

    Previous studies have shown that starvation induces small bowel atrophy, and that atrophy diminishes with aging. In this experiment, we assessed whether starvation-induced atrophy of proximal gut mucosa is associated with the Interleukin-1 receptor (IL-1R) signaling pathway in aged mice. Thirty 26-month-old IL-1R knockout mice and age-matched wild-type C57BL/6 mice were randomly divided into two groups: ad libitum fed and fasted. Mice were euthanized 12 or 48 hours after starvation. The proximal small bowel was harvested for morphologic analysis. Gut epithelial cell proliferation was detected using immunohistochemical staining for proliferating cell nuclear antigen (PCNA), and apoptosis was identified using terminal deoxyuridine nick-end labeling (TUNEL) staining. Aged IL-1R knockout mice were larger than aged-matched wild-type mice (P starvation (P starvation (P Starvation decreased cell proliferation in IL-1R knockout mice (P starvation increases atrophy and is associated with decreased cell proliferation rather than increased apoptosis. Copyright © 2011 Elsevier Inc. All rights reserved.

  5. FANCA knockout in human embryonic stem cells causes a severe growth disadvantage.

    Science.gov (United States)

    Vanuytsel, Kim; Cai, Qing; Nair, Nisha; Khurana, Satish; Shetty, Swati; Vermeesch, Joris R; Ordovas, Laura; Verfaillie, Catherine M

    2014-09-01

    Fanconi anemia (FA) is an autosomal recessive disorder characterized by progressive bone marrow failure (BMF) during childhood, aside from numerous congenital abnormalities. FA mouse models have been generated; however, they do not fully mimic the hematopoietic phenotype. As there is mounting evidence that the hematopoietic impairment starts already in utero, a human pluripotent stem cell model would constitute a more appropriate system to investigate the mechanisms underlying BMF in FA and its developmental basis. Using zinc finger nuclease (ZFN) technology, we have created a knockout of FANCA in human embryonic stem cells (hESC). We introduced a selection cassette into exon 2 thereby disrupting the FANCA coding sequence and found that whereas mono-allelically targeted cells retain an unaltered proliferation potential, disruption of the second allele causes a severe growth disadvantage. As a result, heterogeneous cultures arise due to the presence of cells still carrying an unaffected FANCA allele, quickly outgrowing the knockout cells. When pure cultures of FANCA knockout hESC are pursued either through selection or single cell cloning, this rapidly results in growth arrest and such cultures cannot be maintained. These data highlight the importance of a functional FA pathway at the pluripotent stem cell stage. Copyright © 2014. Published by Elsevier B.V.

  6. Myo5b knockout mice as a model of microvillus inclusion disease

    Science.gov (United States)

    Cartón-García, Fernando; Overeem, Arend W.; Nieto, Rocio; Bazzocco, Sarah; Dopeso, Higinio; Macaya, Irati; Bilic, Josipa; Landolfi, Stefania; Hernandez-Losa, Javier; Schwartz, Simo; Ramon y Cajal, Santiago; van Ijzendoorn, Sven C. D.; Arango, Diego

    2015-01-01

    Inherited MYO5B mutations have recently been associated with microvillus inclusion disease (MVID), an autosomal recessive syndrome characterized by intractable, life-threatening, watery diarrhea appearing shortly after birth. Characterization of the molecular mechanisms underlying this disease and development of novel therapeutic approaches is hampered by the lack of animal models. In this study we describe the phenotype of a novel mouse model with targeted inactivation of Myo5b. Myo5b knockout mice show perinatal mortality, diarrhea and the characteristic mislocalization of apical and basolateral plasma membrane markers in enterocytes. Moreover, in transmission electron preparations, we observed microvillus atrophy and the presence of microvillus inclusion bodies. Importantly, Myo5b knockout embryos at day 20 of gestation already display all these structural defects, indicating that they are tissue autonomous rather than secondary to environmental cues, such as the long-term absence of nutrients in the intestine. Myo5b knockout mice closely resemble the phenotype of MVID patients and constitute a useful model to further investigate the underlying molecular mechanism of this disease and to preclinically assess the efficacy of novel therapeutic approaches. PMID:26201991

  7. Knockout of the Nogo-B Gene Attenuates Tumor Growth and Metastasis in Hepatocellular Carcinoma

    Directory of Open Access Journals (Sweden)

    Bo Zhu

    2017-07-01

    Full Text Available Human hepatocellular carcinoma (HCC is a malignant cancer. It is a challenge to develop anti-HCC drugs due to HCC's extreme aggressiveness and with the sensitivity of the liver to show severe adverse effects. More importantly, the precise mechanisms causing HCC pathogenicity are not known. Our previous study disclosed Nogo-B as a reticulon 4 (Rtn4 family member. In the present study, we first identified that Nogo-B played a critical role in HCC progression. We found, via in vitro and in vivo assays, that Nogo-B was expressed aberrantly in primary HCC tumor tissues and immortal HCC cells but was relatively scarce in the normal liver tissues or cells. Nogo-B knockout, via the CRISPR-Cas9 technique, resulted in significant suppression of HCC cell proliferation and tumor growth. Next-generation sequencing analysis showed that Nogo-B knockout have effects on interleukin-6 (IL-6 signaling pathway. Furthermore, we observed that IL-6 induced phosphorylation of STAT3 (pSTAT3 in wild-type HCC cells, but Nogo-B knockout could reduce IL-6–induced increase of pSTAT3, supporting that Nogo-B affects HCC tumor progression possibly via regulating the IL-6/STAT3 signaling pathway. In conclusion, Nogo-B is expressed aberrantly in HCCs and plays an oncogenic role. These findings support that Nogo-B may be a novel anti-HCC therapeutic target.

  8. Characterization of Phototransduction Gene Knockouts Revealed Important Signaling Networks in the Light-Induced Retinal Degeneration

    Directory of Open Access Journals (Sweden)

    Jayalakshmi Krishnan

    2008-01-01

    Full Text Available Understanding the molecular pathways mediating neuronal function in retinas can be greatly facilitated by the identification of genes regulated in the retinas of different mutants under various light conditions. We attempted to conduct a gene chip analysis study on the genes regulated during rhodopsin kinase (Rhok-/- and arrestin (Sag-/- knockout and double knockouts in mice retina. Hence, mice were exposed to constant illumination of 450 lux or 6,000 lux on dilated pupils for indicated periods. The retinas were removed after the exposure and processed for microarray analysis. Double knockout was associated with immense changes in gene expression regulating a number of apoptosis inducing transcription factors. Subsequently, network analysis revealed that during early exposure the transcription factors, p53, c-MYC, c-FOS, JUN, and, in late phase, NF-B, appeared to be essential for the initiation of light-induced retinal rod loss, and some other classical pro- and antipoptotic genes appeared to be significantly important as well.

  9. Rapid construction of a whole-genome transposon insertion collection for Shewanella oneidensis by Knockout Sudoku.

    Science.gov (United States)

    Baym, Michael; Shaket, Lev; Anzai, Isao A; Adesina, Oluwakemi; Barstow, Buz

    2016-11-10

    Whole-genome knockout collections are invaluable for connecting gene sequence to function, yet traditionally, their construction has required an extraordinary technical effort. Here we report a method for the construction and purification of a curated whole-genome collection of single-gene transposon disruption mutants termed Knockout Sudoku. Using simple combinatorial pooling, a highly oversampled collection of mutants is condensed into a next-generation sequencing library in a single day, a 30- to 100-fold improvement over prior methods. The identities of the mutants in the collection are then solved by a probabilistic algorithm that uses internal self-consistency within the sequencing data set, followed by rapid algorithmically guided condensation to a minimal representative set of mutants, validation, and curation. Starting from a progenitor collection of 39,918 mutants, we compile a quality-controlled knockout collection of the electroactive microbe Shewanella oneidensis MR-1 containing representatives for 3,667 genes that is functionally validated by high-throughput kinetic measurements of quinone reduction.

  10. Generation of ERα-floxed and knockout mice using the Cre/LoxP system

    International Nuclear Information System (INIS)

    Antonson, P.; Omoto, Y.; Humire, P.; Gustafsson, J.-Å.

    2012-01-01

    Highlights: ► ERα floxed and knockout mice were generated. ► Disruption of the ERα gene results in sterility in both male and female mice. ► ERα −/− mice have ovaries with hemorrhagic follicles and hypoplastic uterus. ► Female ERα −/− mice develop obesity. -- Abstract: Estrogen receptor alpha (ERα) is a nuclear receptor that regulates a range of physiological processes in response to estrogens. In order to study its biological role, we generated a floxed ERα mouse line that can be used to knock out ERα in selected tissues by using the Cre/LoxP system. In this study, we established a new ERα knockout mouse line by crossing the floxed ERα mice with Cre deleter mice. Here we show that genetic disruption of the ERα gene in all tissues results in sterility in both male and female mice. Histological examination of uterus and ovaries revealed a dramatically atrophic uterus and hemorrhagic cysts in the ovary. These results suggest that infertility in female mice is the result of functional defects of the reproductive tract. Moreover, female knockout mice are hyperglycemic, develop obesity and at the age of 4 months the body weight of these mice was more than 20% higher compared to wild type littermates and this difference increased over time. Our results demonstrate that ERα is necessary for reproductive tract development and has important functions as a regulator of metabolism in females.

  11. Probing short-range correlations in asymmetric nuclei with quasi-free pair knockout reactions

    Science.gov (United States)

    Stevens, Sam; Ryckebusch, Jan; Cosyn, Wim; Waets, Andreas

    2018-02-01

    Short-range correlations (SRC) in asymmetric nuclei with an unusual neutron-to-proton ratio can be studied with quasi-free two-nucleon knockout processes following the collision between accelerated ions and a proton target. We derive an approximate factorized cross section for those SRC-driven p (A ,p‧N1N2) reactions. Our reaction model hinges on the factorization properties of SRC-driven A (e ,e‧N1N2) reactions for which strong indications are found in theory-experiment comparisons. In order to put our model to the test we compare its predictions with results of 12C (p ,p‧ pn) measurements conducted at Brookhaven National Laboratory (BNL) and find a fair agreement. The model can also reproduce characteristic features of SRC-driven two-nucleon knockout reactions, like back-to-back emission of the correlated nucleons. We study the asymmetry dependence of nuclear SRC by providing predictions for the ratio of proton-proton to proton-neutron knockout cross sections for the carbon isotopes 9-15C thereby covering neutron excess values (N - Z) / Z between -0.5 and +0.5.

  12. Txnip ablation reduces vascular smooth muscle cell inflammation and ameliorates atherosclerosis in apolipoprotein E knockout mice.

    Science.gov (United States)

    Byon, Chang Hyun; Han, Tieyan; Wu, Judy; Hui, Simon T

    2015-08-01

    Inflammation of vascular smooth muscle cells (VSMC) is intimately linked to atherosclerosis and other vascular inflammatory disease. Thioredoxin interacting protein (Txnip) is a key regulator of cellular sulfhydryl redox and a mediator of inflammasome activation. The goals of the present study were to examine the impact of Txnip ablation on inflammatory response to oxidative stress in VSMC and to determine the effect of Txnip ablation on atherosclerosis in vivo. Using cultured VSMC, we showed that ablation of Txnip reduced cellular oxidative stress and increased protection from oxidative stress when challenged with oxidized phospholipids and hydrogen peroxide. Correspondingly, expression of inflammatory markers and adhesion molecules were diminished in both VSMC and macrophages from Txnip knockout mice. The blunted inflammatory response was associated with a decrease in NF-ĸB nuclear translocation. Loss of Txnip in VSMC also led to a dramatic reduction in macrophage adhesion to VSMC. In vivo data from Txnip-ApoE double knockout mice showed that Txnip ablation led to 49% reduction in atherosclerotic lesion in the aortic root and 71% reduction in the abdominal aorta, compared to control ApoE knockout mice. Our data show that Txnip plays an important role in oxidative inflammatory response and atherosclerotic lesion development in mice. The atheroprotective effect of Txnip ablation implicates that modulation of Txnip expression may serve as a potential target for intervention of atherosclerosis and inflammatory vascular disease. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  13. Knockout of targeted gene in porcine somatic cells using zinc-finger nuclease.

    Science.gov (United States)

    Hisamatsu, Shin; Sakaue, Motoharu; Takizawa, Akiko; Kato, Tsubasa; Kamoshita, Maki; Ito, Junya; Kashiwazaki, Naomi

    2015-02-01

    Targeted genome editing is a widely applicable approach for efficiently modifying any sequence of interest in animals. It is very difficult to generate knock-out and knock-in animals except for mice up to now. Very recently, a method of genome editing using zinc-finger nucleases (ZFNs) has been developed to produce knockout rats. Since only injection of ZFNs into the pronuclear (PN) embryo is required, it seems to be useful for generating gene-targeted animals, including domestic species. However, no one has reported the successful production of knockout pigs by direct injection of ZFNs into PN embryos. We examined whether ZFN works on editing the genome of porcine growth hormone receptor in two kinds of cell lines (ST and PT-K75) derived from the pig as a preliminary study. Our data showed that pZFN1/2 vectors were efficiently transfected into both ST and PT-K75 cells. In both cell lines, results from Cel-I assay showed that modification of the targeted gene was confirmed. We injected ZFN1/2 mRNAs into the nucleus of PN stage embryos and then they were transferred to the recipients. However, pups were not delivered. Taken together, ZFN can be an available technology of genome editing even in the pig but further improvement will be required for generating genome-modified pigs. © 2014 Japanese Society of Animal Science.

  14. Less is More: unveiling the functional core of hematopoietic stem cells through knockout mice

    Science.gov (United States)

    Rossi, Lara; Lin, Kuanyin K.; Boles, Nathan C.; Yang, Liubin; King, Katherine Y.; Jeong, Mira; Mayle, Allison; Goodell, Margaret A.

    2012-01-01

    Summary Hematopoietic stem cells (HSCs) represent one of the first recognized somatic stem cells. As such, nearly 200 genes have been examined for roles in HSC function in knockout mice. In this review, we compile the majority of these reports to provide a broad overview of the functional modules revealed by these genetic analyses and highlight some key regulatory pathways involved, including cell cycle control, TGF-β signaling, Pten/AKT signaling, Wnt signaling, and cytokine signaling. Finally, we propose recommendations for characterization of HSC function in knockout mice to facilitate cross-study comparisons that would generate a more cohesive picture of HSC biology. In the field of design, the minimalist movement stripped down buildings and objects to their most basic features, a sentiment that architect Ludwig Mies van der Rohe summarized in his motto “less is more”. By depleting HSCs of specific genes, knockout studies transpose the minimalist approach into research biology, providing insights into the essential core of genetic features that is indispensable for a well-functioning hematopoietic system. PMID:22958929

  15. Hippocampal long-term potentiation is enhanced in urethane-anesthetized RGS2 knockout mice.

    Science.gov (United States)

    Hutchison, R Matthew; Chidiac, Peter; Leung, L Stan

    2009-08-01

    RGS2 is a member of the regulator of G-protein signaling (RGS) family and has been implicated in cellular mechanisms associated with neuronal plasticity. Long-term potentiation (LTP) of RGS2 knockout and wild-type mice was examined at the Schaffer collaterals to CA1 pathway in urethane-anesthetized mice in vivo to examine RGS2's possible role in the regulation of potentiation. As compared to wild-type mice, RGS2 knockouts demonstrated much stronger LTP of the extracellular population spikes at the somatic and dendritic layers in CA1 region and more pronounced LTP of the population excitatory postsynaptic current sink. Under baseline conditions, RGS2 knockouts showed lower paired-pulse facilitation of the excitatory postsynaptic potentials and associated current sinks in vivo as compared with wild-type mice. The data show for the first time that RGS2 deficient mice in vivo differ from wild-type mice in both short-term and long-term synaptic plasticity suggesting that RGS2 serves as a negative regulator of long-term synaptic plasticity. Copyright (c) 2009 Wiley-Liss, Inc.

  16. Utility of P19 Gene-Silencing Suppressor for High Level Expression of Recombinant Human Therapeutic Proteins in Plant Cells

    Directory of Open Access Journals (Sweden)

    Maryam Zangi

    2016-07-01

    Full Text Available Background: The potential of plants, as a safe and eukaryotic system, is considered in the production of recombinant therapeutic human protein today; but the expression level of heterologous proteins is limited by the post-transcriptional gene silencing (PTGS response in this new technology. The use of viral suppressors of gene silencing can prevent PTGS and improve transient expression level of foreign proteins. In this study, we investigated the effect of p19 silencing suppressor on recombinant human nerve growth factor expression in Nicotiana benthamiana. Materials and Methods: The p19 coding region was inserted in the pCAMBIA using NcoI and BstEII recognition sites. Also, the cloned synthesized recombinant human NGF (rhNGF fragment was cloned directly into PVX vector by ClaI and SalI restriction enzymes. The co-agroinfiltration of rhNGF with p19 viral suppressor of gene silencing was evaluated by dot-blot and SDS-PAGE. The amount of expressed rhNGF protein was calculated by AlphaEaseFC software. Results: Co-agroinfiltration of hNGF with P19 suppressor showed about forty-fold increase (8% total soluble protein (TSP when compared to the absence of P19 suppressor (0.2%TSP. Conclusion: The results presented here confirmed that the use of P19 gene silencing suppressor derived from tomato bushy stunt virus (TBSV could efficiently increase the transient expression of recombinant proteins in Nicotiana benthamiana manifold.

  17. Whole genome in vivo RNAi screening identifies the leukemia inhibitory factor receptor as a novel breast tumor suppressor.

    Science.gov (United States)

    Iorns, Elizabeth; Ward, Toby M; Dean, Sonja; Jegg, Anna; Thomas, Dafydd; Murugaesu, Nirupa; Sims, David; Mitsopoulos, Costas; Fenwick, Kerry; Kozarewa, Iwanka; Naceur-Lombarelli, Cristina; Zvelebil, Marketa; Isacke, Clare M; Lord, Christopher J; Ashworth, Alan; Hnatyszyn, H James; Pegram, Mark; Lippman, Marc

    2012-08-01

    Cancer is caused by mutations in oncogenes and tumor suppressor genes, resulting in the deregulation of processes fundamental to the normal behavior of cells. The identification and characterization of oncogenes and tumor suppressors has led to new treatment strategies that have significantly improved cancer outcome. The advent of next generation sequencing has allowed the elucidation of the fine structure of cancer genomes, however, the identification of pathogenic changes is complicated by the inherent genomic instability of cancer cells. Therefore, functional approaches for the identification of novel genes involved in the initiation and development of tumors are critical. Here we report the first whole human genome in vivo RNA interference screen to identify functionally important tumor suppressor genes. Using our novel approach, we identify previously validated tumor suppressor genes including TP53 and MNT, as well as several novel candidate tumor suppressor genes including leukemia inhibitory factor receptor (LIFR). We show that LIFR is a key novel tumor suppressor, whose deregulation may drive the transformation of a significant proportion of human breast cancers. These results demonstrate the power of genome wide in vivo RNAi screens as a method for identifying novel genes regulating tumorigenesis.

  18. Adaptations in pre- and postsynaptic 5-HT(1A) receptor function and cocaine supersensitivity in serotonin transporter knockout rats

    NARCIS (Netherlands)

    Homberg, Judith R; De Boer, Sietse F; Raasø, Halfdan S; Olivier, Jocelien D A; Verheul, Mark; Ronken, Eric; Cools, Alexander R; Ellenbroek, Bart A; Schoffelmeer, Anton N M; Vanderschuren, Louk J M J; De Vries, Taco J; Cuppen, Edwin

    2008-01-01

    RATIONALE: While individual differences in vulnerability to psychostimulants have been largely attributed to dopaminergic neurotransmission, the role of serotonin is not fully understood. OBJECTIVES: To study the rewarding and motivational properties of cocaine in the serotonin transporter knockout

  19. The serotonin transporter plays an important role in male sexual behavior: a study in serotonin transporter knockout rats

    NARCIS (Netherlands)

    Chan, J.Y.; Snoeren, E.; Cuppen, E.; Waldinger, M.; Olivier, B.; Oosting, R.

    2011-01-01

    INTRODUCTION: Serotonin (5-HT) is an important neurotransmitter for sexual behaviors. Heterozygous (+/-) serotonin transporter (SERT) rats and SERT knockout rats (-/-) have serotonergic disturbances with significant elevations of basal extracellular 5-HT levels. AIM: To investigate the putative role

  20. Slit-Robo GTPase-Activating Protein 2 as a metastasis suppressor in osteosarcoma

    OpenAIRE

    Marko, Tracy A.; Shamsan, Ghaidan A.; Edwards, Elizabeth N.; Hazelton, Paige E.; Rathe, Susan K.; Cornax, Ingrid; Overn, Paula R.; Varshney, Jyotika; Diessner, Brandon J.; Moriarity, Branden S.; O?Sullivan, M. Gerard; Odde, David J.; Largaespada, David A.

    2016-01-01

    Osteosarcoma is the most common primary bone tumor, with metastatic disease responsible for most treatment failure and patient death. A forward genetic screen utilizing Sleeping Beauty mutagenesis in mice previously identified potential genetic drivers of osteosarcoma metastasis, including Slit-Robo GTPase-Activating Protein 2 (Srgap2). This study evaluates the potential role of SRGAP2 in metastases-associated properties of osteosarcoma cell lines through Srgap2 knockout via the CRISPR/Cas9 n...

  1. TNF receptor 1, IL-1 receptor, and iNOS genetic knockout mice are not protected from anthrax infection.

    Science.gov (United States)

    Kalns, John; Scruggs, Julie; Millenbaugh, Nancy; Vivekananda, Jeeva; Shealy, David; Eggers, Jeffrey; Kiel, Johnathan

    2002-03-22

    Anthrax produces at least two toxins that cause an intense systemic inflammatory response, edema, shock, and eventually death. The relative contributions of various elements of the immune response to mortality and course of disease progression are poorly understood. We hypothesized that knockout mice missing components of the immune system will have an altered response to infection. Parent strain mice and knockouts were challenged with LD95 of anthrax spores (5 x 10(6)) administered subcutaneously. Our results show that all genetic knockouts succumbed to anthrax infection at the same frequency as the parent. TNF antibody delayed death but TNF receptor 1 knockout had no effect. IL-1 receptor or iNOS knockouts died sooner. Anthrax was more abundant in the injection site of TNF-alpha and iNOS knockouts compared to parent suggesting that attenuated cellular response increases rate of disease progression. With the exception of edema and necrosis at the injection site pathological changes in internal organs were not observed. (C)2002 Elsevier Science (USA).

  2. An In Silico Knockout Model for Gastrointestinal Absorption Using a Systems Pharmacology Approach - Development and Application for Ketones.

    Directory of Open Access Journals (Sweden)

    Vittal Shivva

    Full Text Available Gastrointestinal absorption and disposition of ketones is complex. Recent work describing the pharmacokinetics (PK of d-β-hydroxybutyrate (BHB following oral ingestion of a ketone monoester ((R-3-hydroxybutyl (R-3-hydroxybutyrate found multiple input sites, nonlinear disposition and feedback on endogenous production. In the current work, a human systems pharmacology model for gastrointestinal absorption and subsequent disposition of small molecules (monocarboxylic acids with molecular weight < 200 Da was developed with an application to a ketone monoester. The systems model was developed by collating the information from the literature and knowledge gained from empirical population modelling of the clinical data. In silico knockout variants of this systems model were used to explore the mechanism of gastrointestinal absorption of ketones. The knockouts included active absorption across different regions in the gut and also a passive diffusion knockout, giving 10 gut knockouts in total. Exploration of knockout variants has suggested that there are at least three distinct regions in the gut that contribute to absorption of ketones. Passive diffusion predominates in the proximal gut and active processes contribute to the absorption of ketones in the distal gut. Low doses are predominantly absorbed from the proximal gut by passive diffusion whereas high doses are absorbed across all sites in the gut. This work has provided mechanistic insight into the absorption process of ketones, in the form of unique in silico knockouts that have potential for application with other therapeutics. Future studies on absorption process of ketones are suggested to substantiate findings in this study.

  3. Development of the Multiple Gene Knockout System with One-Step PCR in Thermoacidophilic Crenarchaeon Sulfolobus acidocaldarius

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    Shoji Suzuki

    2017-01-01

    Full Text Available Multiple gene knockout systems developed in the thermoacidophilic crenarchaeon Sulfolobus acidocaldarius are powerful genetic tools. However, plasmid construction typically requires several steps. Alternatively, PCR tailing for high-throughput gene disruption was also developed in S. acidocaldarius, but repeated gene knockout based on PCR tailing has been limited due to lack of a genetic marker system. In this study, we demonstrated efficient homologous recombination frequency (2.8 × 104 ± 6.9 × 103 colonies/μg DNA by optimizing the transformation conditions. This optimized protocol allowed to develop reliable gene knockout via double crossover using short homologous arms and to establish the multiple gene knockout system with one-step PCR (MONSTER. In the MONSTER, a multiple gene knockout cassette was simply and rapidly constructed by one-step PCR without plasmid construction, and the PCR product can be immediately used for target gene deletion. As an example of the applications of this strategy, we successfully made a DNA photolyase- (phr- and arginine decarboxylase- (argD- deficient strain of S. acidocaldarius. In addition, an agmatine selection system consisting of an agmatine-auxotrophic strain and argD marker was also established. The MONSTER provides an alternative strategy that enables the very simple construction of multiple gene knockout cassettes for genetic studies in S. acidocaldarius.

  4. The Heterologous Expression of the p22 RNA Silencing Suppressor of the Crinivirus Tomato Chlorosis Virus from Tobacco Rattle Virus and Potato Virus X Enhances Disease Severity but Does Not Complement Suppressor-Defective Mutant Viruses.

    Science.gov (United States)

    Landeo-Ríos, Yazmín; Navas-Castillo, Jesús; Moriones, Enrique; Cañizares, M. Carmen

    2017-11-24

    To counteract host antiviral RNA silencing, plant viruses express suppressor proteins that function as pathogenicity enhancers. The genome of the Tomato chlorosis virus (ToCV) (genus Crinivirus , family Closteroviridae ) encodes an RNA silencing suppressor, the protein p22, that has been described as having one of the longest lasting local suppressor activities when assayed in Nicotiana benthamiana . Since suppression of RNA silencing and the ability to enhance disease severity are closely associated, we analyzed the effect of expressing p22 in heterologous viral contexts. Thus, we studied the effect of the expression of ToCV p22 from viral vectors Tobacco rattle virus (TRV) and Potato virus X (PVX), and from attenuated suppressor mutants in N. benthamiana plants. Our results show that although an exacerbation of disease symptoms leading to plant death was observed in the heterologous expression of ToCV p22 from both viruses, only in the case of TRV did increased viral accumulation occur. The heterologous expression of ToCV p22 could not complement suppressor-defective mutant viruses.

  5. Generation of Hoxc13 knockout pigs recapitulates human ectodermal dysplasia-9.

    Science.gov (United States)

    Han, Kai; Liang, Liuping; Li, Li; Ouyang, Zhen; Zhao, Bentian; Wang, Qi; Liu, Zhaoming; Zhao, Yu; Ren, Xiaoshuai; Jiang, Fei; Lai, Chengdan; Wang, Kepin; Yan, Sen; Huang, Liang; Guo, Lin; Zeng, Kang; Lai, Liangxue; Fan, Nana

    2017-01-01

    Atrichia and sparse hair phenotype cause distress to many patients. Ectodermal dysplasia-9 (ED-9) is a congenital condition characterized by hypotrichosis and nail dystrophy without other disorders, and Hoxc13 is a pathogenic gene for ED-9. However, mice carrying Hoxc13 mutation present several other serious disorders, such as skeletal defects, progressive weight loss and low viability. Mouse models cannot faithfully mimic human ED-9. In this study, we generated an ED-9 pig model via Hoxc13 gene knockout through single-stranded oligonucleotides (c.396C > A) combined with CRISPR/Cas9 and somatic cell nuclear transfer. Eight cloned piglets with three types of biallelic mutations (five piglets with Hoxc13c.396C > A/c.396C > A, two piglets with Hoxc13c.396C > A/c.396C > A + 1 and one piglet with Hoxc13Δ40/Δ40) were obtained. Hoxc13 was not expressed in pigs with all three mutation types, and the expression levels of Hoxc13-regulated genes, namely, Foxn1, Krt85 and Krt35, were decreased. The hair follicles displayed various abnormal phenotypes, such as reduced number of follicles and disarrayed hair follicle cable without normal hair all over the body. By contrast, the skin structure, skeleton phenotype, body weight gain and growth of Hoxc13 knockout pigs were apparently normal. The phenotypes of Hoxc13 mutation in pigs were similar to those in ED-9 patients. Therefore, Hoxc13 knockout pigs could be utilized as a model for ED-9 pathogenesis and as a hairless model for hair regeneration research. Moreover, the hairless pigs without other major abnormal phenotypes generated in this study could be effective models for other dermatological research because of the similarity between pig and human skins. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  6. Unintentional miRNA ablation is a risk factor in gene knockout studies: a short report.

    Directory of Open Access Journals (Sweden)

    Ivan Osokine

    2008-02-01

    Full Text Available One of the most powerful techniques for studying the function of a gene is to disrupt the expression of that gene using genetic engineering strategies such as targeted recombination or viral integration of gene trap cassettes. The tremendous utility of these tools was recognized this year with the awarding of the Nobel Prize in Physiology or Medicine to Capecchi, Evans, and Smithies for their pioneering work in targeted recombination mutagenesis in mammals. Another noteworthy discovery made nearly a decade ago was the identification of a novel class of non-coding genes called microRNAs. MicroRNAs are among the largest known classes of regulatory elements with more than 1000 predicted to exist in the mouse genome. Over 50% of known microRNAs are located within introns of coding genes. Given that currently about half of the genes in mouse have been knocked out, we investigated the possibility that intronic microRNAs may have been coincidentally deleted or disrupted in some of these mouse models. We searched published murine knockout studies and gene trap embryonic stem cell line databases for cases where a microRNA was located within or near the manipulated genomic loci, finding almost 200 cases where microRNA expression may have been disrupted along with another gene. Our results draw attention to the need for careful planning in future knockout studies to minimize the unintentional disruption of microRNAs. These data also raise the possibility that many knockout studies may need to be reexamined to determine if loss of a microRNA contributes to the phenotypic consequences attributed to loss of a protein-encoding gene.

  7. Generation of ER{alpha}-floxed and knockout mice using the Cre/LoxP system

    Energy Technology Data Exchange (ETDEWEB)

    Antonson, P., E-mail: per.antonson@ki.se [Department of Biosciences and Nutrition, Karolinska Institutet, Novum, SE-141 83 Huddinge (Sweden); Omoto, Y.; Humire, P. [Department of Biosciences and Nutrition, Karolinska Institutet, Novum, SE-141 83 Huddinge (Sweden); Gustafsson, J.-A. [Department of Biosciences and Nutrition, Karolinska Institutet, Novum, SE-141 83 Huddinge (Sweden); Center for Nuclear Receptors and Cell Signaling, Department of Biology and Biochemistry, University of Houston, Houston, TX 77204 (United States)

    2012-08-10

    Highlights: Black-Right-Pointing-Pointer ER{alpha} floxed and knockout mice were generated. Black-Right-Pointing-Pointer Disruption of the ER{alpha} gene results in sterility in both male and female mice. Black-Right-Pointing-Pointer ER{alpha}{sup -/-} mice have ovaries with hemorrhagic follicles and hypoplastic uterus. Black-Right-Pointing-Pointer Female ER{alpha}{sup -/-} mice develop obesity. -- Abstract: Estrogen receptor alpha (ER{alpha}) is a nuclear receptor that regulates a range of physiological processes in response to estrogens. In order to study its biological role, we generated a floxed ER{alpha} mouse line that can be used to knock out ER{alpha} in selected tissues by using the Cre/LoxP system. In this study, we established a new ER{alpha} knockout mouse line by crossing the floxed ER{alpha} mice with Cre deleter mice. Here we show that genetic disruption of the ER{alpha} gene in all tissues results in sterility in both male and female mice. Histological examination of uterus and ovaries revealed a dramatically atrophic uterus and hemorrhagic cysts in the ovary. These results suggest that infertility in female mice is the result of functional defects of the reproductive tract. Moreover, female knockout mice are hyperglycemic, develop obesity and at the age of 4 months the body weight of these mice was more than 20% higher compared to wild type littermates and this difference increased over time. Our results demonstrate that ER{alpha} is necessary for reproductive tract development and has important functions as a regulator of metabolism in females.

  8. Generation of beta-lactoglobulin knock-out goats using CRISPR/Cas9

    Science.gov (United States)

    Zhou, Wenjun; Wan, Yongjie; Guo, Rihong; Deng, Mingtian; Deng, Kaiping; Wang, Zhen; Zhang, Yanli; Wang, Feng

    2017-01-01

    Goat’s milk, considered a substitute for cow’s milk, has a high nutritional value. However, goat’s milk contains various allergens, predominantly β-lactoglobulin (BLG). In this study, we employed the CRISPR/Cas9 system to target the BLG locus in goat fibroblasts for sgRNA optimization and generate BLG knock-out goats through co-injection of Cas9 mRNA and small guide RNAs (sgRNAs) into goat embryos at the one-cell stage. We firstly tested sgRNA editing efficiencies in goat fibroblast cells, and approximately 8.00%–9.09% of the cells were modified in single sgRNA-guided targeting experiment. Among the kids, the genome-targeting efficiencies of single sgRNA were 12.5% (10 ng/μL sg1) and 0% (10 ng/μL sg2) and efficiencies of dual sgRNAs were 25.0% (25 ng/μL sg2+sg3 group) and 28.6% (50 ng/μL sg2+sg3 group). Relative expression of BLG in BLG knock-out goat mammary glands significantly (p milk protein coding genes, such as CSN1S1, CSN1S2, CSN2, CSN3 and LALBA (p milk of the BLG knock-out goat. In addition, most of the targeted kids were chimeric (3/4), and their various body tissues were edited simultaneously. Our study thus provides a basis for optimizing the quality of goat milk, which can be applied to biomedical and agricultural research. PMID:29016691

  9. Generation of beta-lactoglobulin knock-out goats using CRISPR/Cas9.

    Science.gov (United States)

    Zhou, Wenjun; Wan, Yongjie; Guo, Rihong; Deng, Mingtian; Deng, Kaiping; Wang, Zhen; Zhang, Yanli; Wang, Feng

    2017-01-01

    Goat's milk, considered a substitute for cow's milk, has a high nutritional value. However, goat's milk contains various allergens, predominantly β-lactoglobulin (BLG). In this study, we employed the CRISPR/Cas9 system to target the BLG locus in goat fibroblasts for sgRNA optimization and generate BLG knock-out goats through co-injection of Cas9 mRNA and small guide RNAs (sgRNAs) into goat embryos at the one-cell stage. We firstly tested sgRNA editing efficiencies in goat fibroblast cells, and approximately 8.00%-9.09% of the cells were modified in single sgRNA-guided targeting experiment. Among the kids, the genome-targeting efficiencies of single sgRNA were 12.5% (10 ng/μL sg1) and 0% (10 ng/μL sg2) and efficiencies of dual sgRNAs were 25.0% (25 ng/μL sg2+sg3 group) and 28.6% (50 ng/μL sg2+sg3 group). Relative expression of BLG in BLG knock-out goat mammary glands significantly (p milk protein coding genes, such as CSN1S1, CSN1S2, CSN2, CSN3 and LALBA (p milk of the BLG knock-out goat. In addition, most of the targeted kids were chimeric (3/4), and their various body tissues were edited simultaneously. Our study thus provides a basis for optimizing the quality of goat milk, which can be applied to biomedical and agricultural research.

  10. Generation of beta-lactoglobulin knock-out goats using CRISPR/Cas9.

    Directory of Open Access Journals (Sweden)

    Wenjun Zhou

    Full Text Available Goat's milk, considered a substitute for cow's milk, has a high nutritional value. However, goat's milk contains various allergens, predominantly β-lactoglobulin (BLG. In this study, we employed the CRISPR/Cas9 system to target the BLG locus in goat fibroblasts for sgRNA optimization and generate BLG knock-out goats through co-injection of Cas9 mRNA and small guide RNAs (sgRNAs into goat embryos at the one-cell stage. We firstly tested sgRNA editing efficiencies in goat fibroblast cells, and approximately 8.00%-9.09% of the cells were modified in single sgRNA-guided targeting experiment. Among the kids, the genome-targeting efficiencies of single sgRNA were 12.5% (10 ng/μL sg1 and 0% (10 ng/μL sg2 and efficiencies of dual sgRNAs were 25.0% (25 ng/μL sg2+sg3 group and 28.6% (50 ng/μL sg2+sg3 group. Relative expression of BLG in BLG knock-out goat mammary glands significantly (p < 0.01 decreased as well as other milk protein coding genes, such as CSN1S1, CSN1S2, CSN2, CSN3 and LALBA (p < 0.05. As expected, BLG protein had been abolished in the milk of the BLG knock-out goat. In addition, most of the targeted kids were chimeric (3/4, and their various body tissues were edited simultaneously. Our study thus provides a basis for optimizing the quality of goat milk, which can be applied to biomedical and agricultural research.

  11. IKKε knockout prevents high fat diet induced arterial atherosclerosis and NF-κB signaling in mice.

    Directory of Open Access Journals (Sweden)

    Changchun Cao

    Full Text Available AIMS: Atherosclerosis is a public health concern affecting many worldwide, but its pathogenesis remains unclear. In this study we investigated the role of IKKε during the formation of atherosclerosis and its molecular mechanism in the mouse aortic vessel wall. METHODS AND RESULTS: C57BL/6 wild-type or IKKε knockout mice bred into the ApoE knockout genetic background were divided into 4 groups: (1 wild-type (WT, (2 ApoE knockout (AK, (3 IKKε knockout (IK, (4 or both ApoE and IKKε knockout (DK. Each group of mice were fed with a high fat diet (HFD for 12 weeks from 8 weeks of age. Immunohistochemistry and Western blotting analysis demonstrated obvious increases in the expression of IKKε in the AK group compared with the WT group, especially in the intima. Serum lipid levels were significantly higher in the AK and DK groups than in the other two groups. Staining with hematoxylin-eosin and Oil Red, as well as scanning electron microscopy revealed less severe atherosclerotic lesions in the DK group than in the AK group. Immunofluorescence and Western blot analysis demonstrated obvious increases in the expression of NF-κB pathway components and downstream factors in the AK group, especially in the intima, while these increases were blocked in the DK group. CONCLUSION: The knockout of IKKε prevented significant atherosclerosis lesions in the mouse aorta from in both wild-type and ApoE knockout mice fed a HFD, suggesting that IKKε may play a vital role in HFD-induced atherosclerosis and would be an important target for the treatment of atherosclerosis.

  12. Remodeling epigenetic modifications at tumor suppressor gene promoters with bovine oocyte extract.

    Science.gov (United States)

    Wang, Zhenfei; Yue, Yongli; Han, Pengyong; Sa, Rula; Ren, Xiaolv; Wang, Jie; Bai, Haidong; Yu, Haiquan

    2013-09-01

    Epigenetic silencing of tumor suppressor genes by aberrant DNA methylation and histone modifications at their promoter regions plays an important role in the initiation and progression of cancer. The therapeutic effect of the widely used epigenetic drugs, including DNA methyltransferase inhibitors and histone deacetylase inhibitors, remains unsatisfactory. One important underlying factor in the ineffectiveness of these drugs is that their actions lack specificity. To investigate whether oocyte extract can be used for epigenetic re-programming of cancer cells, H460 human lung cancer cells were reversibly permeabilized and incubated with bovine oocyte extract. Bisulfite sequencing showed that bovine oocyte extract induced significant demethylation at hypermethylated promoter CpG islands of the tumor suppressor genes RUNX3 and CDH1; however, the DNA methylation levels of repetitive sequences were not affected. Chromatin immunoprecipitation showed that bovine oocyte extract significantly reduced transcriptionally repressive histone modifications and increased transcriptionally activating histone modifications at the promoter regions of RUNX3 and CDH1. Bovine oocyte extract reactivated the expression of RUNX3 and CDH1 at both the messenger RNA and the protein levels without up-regulating the transcription of pluripotency-associated genes. At the functional level, anchorage-independent proliferation, migration and invasion of H460 cells was strongly inhibited. These results demonstrate that bovine oocyte extract reactivates epigenetically silenced tumor suppressor genes by remodeling the epigenetic modifications at their promoter regions. Bovine oocyte extract may provide a useful tool for investigating epigenetic mechanisms in cancer and a valuable source for developing novel safe therapeutic approaches that target epigenetic alterations. Copyright © 2013 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

  13. Increased Salt-Sensitivity in Endothelial Nitric Oxide Synthase-Knockout Mice

    OpenAIRE

    Leonard, Allison M.; Chafe, Linda L.; Montani, Jean-Pierre; Van Vliet, Bruce N.

    2017-01-01

    Background: Although impaired nitric oxide production contributes importantly to salt-sensitivity, the role of the endothelial isoform of nitric oxide synthase (eNOS) has received little attention. In the present study we compared the effects of a high-salt diet on the blood pressure response of eNOS knockout (eNOS−/−) and control (eNOS+/+) mice. Methods: Mean arterial pressure (MAP), heart rate, pulse pressure, and activity levels were recorded by telemetry in mice fed a regular-salt diet (0...

  14. Transcriptomic profiling comparison of YAP over-expression and conditional knockout mouse tooth germs

    Directory of Open Access Journals (Sweden)

    Ming Liu

    2015-09-01

    Full Text Available To identify the downstream target genes of YAP, we used RNA-Seq technology to compare the transcriptomic profilings of Yap conditional knockout (Yap CKO and YAP over-expression mouse tooth germs. Our results showed that some Hox, Wnt and Laminin family genes had concurrent changes with YAP transcripts, indicating that the expression of these genes may be regulated by YAP. Here, we provide the detailed experimental procedure for the transcriptomic profiling results (NCBI GEO accession number GSE65524. The associated study on the regulation of Hoxa1 and Hoxc13 genes by YAP was published in Molecular Cellular Biology in 2015 [Liu et al., 2015].

  15. Transcriptomic profiling comparison of YAP over-expression and conditional knockout mouse tooth germs.

    Science.gov (United States)

    Liu, Ming; Wang, Xiu-Ping

    2015-09-01

    To identify the downstream target genes of YAP, we used RNA-Seq technology to compare the transcriptomic profilings of Yap conditional knockout (Yap CKO) and YAP over-expression mouse tooth germs. Our results showed that some Hox, Wnt and Laminin family genes had concurrent changes with YAP transcripts, indicating that the expression of these genes may be regulated by YAP. Here, we provide the detailed experimental procedure for the transcriptomic profiling results (NCBI GEO accession number GSE65524). The associated study on the regulation of Hoxa1 and Hoxc13 genes by YAP was published in Molecular Cellular Biology in 2015 [Liu et al., 2015].

  16. Prohormone convertase 2 activity is increased in the hippocampus of Wfs1 knockout mice

    Directory of Open Access Journals (Sweden)

    Karin eTein

    2015-08-01

    Full Text Available BackgroundMutations in WFS1 gene cause Wolfram syndrome, which is a rare autosomal recessive disorder, characterized by diabetes insipidus, diabetes mellitus, optic nerve atrophy and deafness (DIDMOAD. The WFS1 gene product wolframin is located in the endoplasmic reticulum. Mice lacking this gene exhibit disturbances in the processing and secretion of peptides, such as vasopressin and insulin. In the brain, high levels of the wolframin protein have been observed in the hippocampus, amygdala and limbic structures. The aim of this study was to investigate the effect of Wfs1 knockout on peptide processing in mouse hippocampus. A peptidomic approach was used to characterize individual peptides in the hippocampus of wild-type and Wfs1 knockout mice. ResultsWe identified 126 peptides in hippocampal extracts and the levels of 10 peptides differed between Wfs1 KO and wild-type mice at P<0.05. The peptide with the largest alteration was little-LEN, which level was 25 times higher in the hippocampus of Wfs1 KO mice compared to wild-type mice. Processing (cleavage of little-LEN from the Pcsk1n gene product proSAAS involves prohormone convertase 2 (PC2. Thus, PC2 activity was measured in extracts prepared from the hippocampus of Wfs1 knockout mice. The activity of PC2 in Wfs1 mutant mice was significantly higher (149.9±2.3%, p<0.0001, n=8 than in wild-type mice (100.0±7.0%, n=8. However, Western blot analysis showed that protein levels of 7B2, proPC2 and PC2 were same in both groups, and so were gene expression levels.ConclusionsProcessing of proSAAS is altered in the hippocampus of Wfs1-KO mice, which is caused by increased activity of PC2. Increased activity of PC2 in Wfs1 knockout mice is not caused by alteration in the levels of PC2 protein. Our results suggest a functional link between Wfs1 and PC2. Thus, the detailed molecular mechanism of the role of Wfs1 in the regulation of PC2 activity needs further investigation.

  17. Wip1 knockout inhibits the proliferation and enhances the migration of bone marrow mesenchymal stem cells

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Yiting [College of Animal Science and Technology, Nanjing Agricultural University, Nanjing 210095 (China); State Key Laboratory of Animal Nutrition and Key Laboratory of Farm Animal Genetic Resources and Germplasm Innovation of Ministry of Agriculture, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193 (China); Liu, Lan [State Key Laboratory of Animal Nutrition and Key Laboratory of Farm Animal Genetic Resources and Germplasm Innovation of Ministry of Agriculture, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193 (China); Sheng, Ming [College of Animal Science and Technology, Nanjing Agricultural University, Nanjing 210095 (China); Xiong, Kai [Department of Veterinary Clinical and Animal Sciences, University of Copenhagen, Grønnegårdsvej 7, 1870 Frederiksberg C (Denmark); Huang, Lei; Gao, Qian; Wei, Jingliang; Wu, Tianwen; Yang, Shulin [State Key Laboratory of Animal Nutrition and Key Laboratory of Farm Animal Genetic Resources and Germplasm Innovation of Ministry of Agriculture, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193 (China); Liu, Honglin, E-mail: liuhonglinnjau@163.com [College of Animal Science and Technology, Nanjing Agricultural University, Nanjing 210095 (China); Mu, Yulian, E-mail: muyulian76@iascaas.net.cn [State Key Laboratory of Animal Nutrition and Key Laboratory of Farm Animal Genetic Resources and Germplasm Innovation of Ministry of Agriculture, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193 (China); Li, Kui [State Key Laboratory of Animal Nutrition and Key Laboratory of Farm Animal Genetic Resources and Germplasm Innovation of Ministry of Agriculture, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193 (China)

    2015-06-10

    Mesenchymal stem cells (MSCs), a unique population of multipotent adult progenitor cells originally found in bone marrow (BM), are extremely useful for multifunctional therapeutic approaches. However, the growth arrest and premature senescence of MSCs in vitro prevent the in-depth characterization of these cells. In addition, the regulatory factors involved in MSCs migration remain largely unknown. Given that protein phosphorylation is associated with the processes of MSCs proliferation and migration, we focused on wild-type p53-inducible phosphatase-1 (Wip1), a well-studied modulator of phosphorylation, in this study. Our results showed that Wip1 knockout significantly inhibited MSCs proliferation and induced G2-phase cell-cycle arrest by reducing cyclinB1 expression. Compared with WT-MSCs, Wip1{sup −/−} MSCs displayed premature growth arrest after six passages in culture. Transwell and scratch assays revealed that Wip1{sup −/−} MSCs migrate more effectively than WT-MSCs. Moreover, the enhanced migratory response of Wip1{sup −/−} MSCs may be attributed to increases in the induction of Rac1-GTP activity, the pAKT/AKT ratio, the rearrangement of filamentous-actin (f-actin), and filopodia formation. Based on these results, we then examined the effect of treatment with a PI3K/AKT and Rac1 inhibitor, both of which impaired the migratory activity of MSCs. Therefore, we propose that the PI3K/AKT/Rac1 signaling axis mediates the Wip1 knockout-induced migration of MSCs. Our findings indicate that the principal function of Wip1 in MSCs transformation is the maintenance of proliferative capacity. Nevertheless, knocking out Wip1 increases the migratory capacity of MSCs. This dual effect of Wip1 provides the potential for purposeful routing of MSCs. - Highlights: • Wip1 knockout inhibited MSCs proliferation through reducing cyclinB1 expression. • Wip1{sup −/−} MSCs displayed premature growth arrest in vitro after six passages. • Knocking out Wip1

  18. Knockout of Tmem70 alters biogenesis of ATP synthase and leads to embryonal lethality in mice

    Czech Academy of Sciences Publication Activity Database

    Vrbacký, Marek; Kovalčíková, Jana; Chawengsaksophak, Kallayanee; Beck, Inken; Mráček, Tomáš; Nůsková, Hana; Sedmera, David; Papoušek, František; Kolář, František; Sobol, Margaryta; Hozák, Pavel; Sedláček, Radislav; Houštěk, Josef

    2016-01-01

    Roč. 25, č. 21 (2016), s. 4674-4685 ISSN 0964-6906 R&D Projects: GA ČR(CZ) GB14-36804G; GA MŠk(CZ) LL1204; GA MŠk(CZ) ED1.1.00/02.0109; GA TA ČR(CZ) TE01020118; GA MŠk(CZ) LM2015062; GA MZd(CZ) NV16-33018A; GA MŠk(CZ) LM2015040 Institutional support: RVO:67985823 ; RVO:68378050 Keywords : mouse knockout * mitochondria * ATP synthase * TMEM70 * biogenesis * mitochondrial disease s Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 5.340, year: 2016

  19. Attenuated vasodilator effectiveness of protease-activated receptor 2 agonist in heterozygous par2 knockout mice.

    Directory of Open Access Journals (Sweden)

    John C Hennessey

    Full Text Available Studies of homozygous PAR2 gene knockout mice have described a mix of phenotypic effects in vitro and in vivo. However, there have been few studies of PAR2 heterozygous (wild-type/knockout; PAR2-HET mice. The phenotypes of many hemi and heterozygous transgenic mice have been described as intermediates between those of wild-type and knockout animals. In our study we aimed to determine the effects of intermediary par2 gene zygosity on vascular tissue responses to PAR2 activation. Specifically, we compared the vasodilator effectiveness of the PAR2 activating peptide 2-furoyl-LIGRLO-amide in aortas of wild-type PAR2 homozygous (PAR2-WT and PAR2-HET mice. In myographs under isometric tension conditions, isolated aortic rings were contracted by alpha 1-adrenoeceptor agonist (phenylephrine, and thromboxane receptor agonist (U46619 and then relaxation responses by the additions of 2-furoyl-LIGRLO-amide, acetylcholine, and nitroprusside were recorded. A Schild regression analysis of the inhibition by a PAR2 antagonist (GB-83 of PAR2 agonist-induced aortic ring relaxations was used to compare receptor expression in PAR2-WT to PAR2-HET. PAR2 mRNA in aortas was measured by quantitative real-time PCR. In aortas contracted by either phenylephrine or U46619, the maximum relaxations induced by 2-furoyl-LIGRLO-amide were less in PAR2-HET than in the gender-matched PAR2-WT. GB-83 was 3- to 4-fold more potent for inhibition of 2fly in PAR2-HET than in PAR2-WT. PAR2 mRNA content of aortas from PAR2-HET was not significantly different than in PAR2-WT. Acetylcholine- and nitroprusside-induced relaxations of aortas from PAR2-HET were not significantly different than in PAR2-WT and PAR2 knockout. An interesting secondary finding was that relaxations induced by agonists of PAR2 and muscarinic receptors were larger in females than in males. We conclude that the lower PAR2-mediated responses in PAR2-HET aortas are consistent with evidence of a lower quantity of functional

  20. Wip1 knockout inhibits the proliferation and enhances the migration of bone marrow mesenchymal stem cells

    International Nuclear Information System (INIS)

    Tang, Yiting; Liu, Lan; Sheng, Ming; Xiong, Kai; Huang, Lei; Gao, Qian; Wei, Jingliang; Wu, Tianwen; Yang, Shulin; Liu, Honglin; Mu, Yulian; Li, Kui

    2015-01-01

    Mesenchymal stem cells (MSCs), a unique population of multipotent adult progenitor cells originally found in bone marrow (BM), are extremely useful for multifunctional therapeutic approaches. However, the growth arrest and premature senescence of MSCs in vitro prevent the in-depth characterization of these cells. In addition, the regulatory factors involved in MSCs migration remain largely unknown. Given that protein phosphorylation is associated with the processes of MSCs proliferation and migration, we focused on wild-type p53-inducible phosphatase-1 (Wip1), a well-studied modulator of phosphorylation, in this study. Our results showed that Wip1 knockout significantly inhibited MSCs proliferation and induced G2-phase cell-cycle arrest by reducing cyclinB1 expression. Compared with WT-MSCs, Wip1 −/− MSCs displayed premature growth arrest after six passages in culture. Transwell and scratch assays revealed that Wip1 −/− MSCs migrate more effectively than WT-MSCs. Moreover, the enhanced migratory response of Wip1 −/− MSCs may be attributed to increases in the induction of Rac1-GTP activity, the pAKT/AKT ratio, the rearrangement of filamentous-actin (f-actin), and filopodia formation. Based on these results, we then examined the effect of treatment with a PI3K/AKT and Rac1 inhibitor, both of which impaired the migratory activity of MSCs. Therefore, we propose that the PI3K/AKT/Rac1 signaling axis mediates the Wip1 knockout-induced migration of MSCs. Our findings indicate that the principal function of Wip1 in MSCs transformation is the maintenance of proliferative capacity. Nevertheless, knocking out Wip1 increases the migratory capacity of MSCs. This dual effect of Wip1 provides the potential for purposeful routing of MSCs. - Highlights: • Wip1 knockout inhibited MSCs proliferation through reducing cyclinB1 expression. • Wip1 −/− MSCs displayed premature growth arrest in vitro after six passages. • Knocking out Wip1 increases the migratory

  1. Increased susceptibility to diet-induced obesity in GPRC6A receptor knockout mice

    DEFF Research Database (Denmark)

    Clemmensen, Christoffer; Smajilovic, Sanela; Madsen, Andreas N

    2013-01-01

    locomotor activity. Moreover, diet-induced obese Gprc6a KO mice had increased circulating insulin and leptin levels relative to WT animals, thereby demonstrating that endocrine abnormalities associate with the reported disturbances in energy balance. The phenotype was further accompanied by disruptions...... complications is still elusive. In the present study, we investigated the impact of GPRC6A deficiency in a murine model of diet-induced obesity (DIO). Male Gprc6a knockout (KO) mice and WT littermates were subjected to a high-fat diet (HFD) for 25 weeks and exposed to comprehensive metabolic phenotyping...

  2. Hepatic caveolin-1 is enhanced in Cyp27a1/ApoE double knockout mice

    OpenAIRE

    Escher, Geneviève; Zurkinden, Line; Mistry, H; Mansour, Y; Rohrbach, B; Vogt, Bruno

    2016-01-01

    Sterol 27?hydroxylase (CYP27A1) is involved in bile acid synthesis and cholesterol homoeostasis. Cyp27a1 (?/?)/Apolipoprotein E (?/?) double knockout mice (DKO) fed a western diet failed to develop atherosclerosis. Caveolin?1 (CAV?1), the main component of caveolae, is associated with lipid homoeostasis and has regulatory roles in vascular diseases. We hypothesized that liver CAV?1 would contribute to the athero?protective mechanism in DKO mice. Cyp27a1 (+/+)/ApoE (?/?) (ApoE KO), Cyp27a1 (+/...

  3. Chemokine receptor CXCR4 downregulated by von Hippel-Lindau tumour suppressor pVHL

    DEFF Research Database (Denmark)

    Staller, Peter; Sulitkova, Jitka; Lisztwan, Joanna

    2003-01-01

    regulates CXCR4 expression owing to its capacity to target hypoxia-inducible factor (HIF) for degradation under normoxic conditions. This process is suppressed under hypoxic conditions, resulting in HIF-dependent CXCR4 activation. An analysis of clear cell renal carcinoma that manifests mutation of the VHL...... of the CXCR4-specific ligand stromal cell-derived factor-1alpha (ref. 1). It is still uncertain how an evolving tumour cell is reprogrammed to express CXCR4, thus implementing the tendency to metastasize to specific organs. Here we show that the von Hippel-Lindau tumour suppressor protein pVHL negatively...

  4. Breast cancer metastasis suppressor 1 (BRMS1) is stabilized by the Hsp90 chaperone #

    OpenAIRE

    Hurst, Douglas R.; Mehta, Alka; Moore, Blake P.; Phadke, Pushkar A.; Meehan, William J.; Accavitti, Mary Ann; Shevde, Lalita A.; Hopper, James E.; Xie, Yi; Welch, Danny R.; Samant, Rajeev S.

    2006-01-01

    Breast cancer metastasis suppressor 1 (BRMS1) is a member of the mSin3-HDAC transcription co-repressor complex. However, the proteins associated with BRMS1 have not been fully identified. Yeast two-hybrid screen, immuno-affinity chromatography, and co-immunoprecipitation experiments were performed to identify BRMS1 interacting proteins. In addition to known core mSin3 transcriptional complex components RBBP1 and mSDS3, BRMS1 interacted with other proteins including three chaperones: DNAJB6 (M...

  5. Role of natural antisense transcripts pertaining to tumor suppressor genes in human carcinomas

    International Nuclear Information System (INIS)

    Pelicci, G.; Pierotti, M.

    2009-01-01

    Overlapping transcripts in opposite orientations can potentially form perfect sense-antisense duplex RNA. Recently, several studies have revealed the extent of natural antisense transcripts (NATs) and their role in important biological phenomena also in higher organisms. In order to test the hypothesis that the function of NATs in man might represent an essential element in the regulation of gene expression, especially at transcriptional level, in this study we planned to look for, systematically examine, and characterize NATs belonging in the human genome to the tumour suppressor class of genes, so to identify physiological (and potentially pathological) modulators in this gene class

  6. Wilms' tumours: about tumour suppressor genes, an oncogene and a chameleon gene.

    Science.gov (United States)

    Huff, Vicki

    2011-02-01

    Genes identified as being mutated in Wilms' tumour include TP53, a classic tumour suppressor gene (TSG); CTNNB1 (encoding β-catenin), a classic oncogene; WTX, which accumulating data indicate is a TSG; and WT1, which is inactivated in some Wilms' tumours, similar to a TSG. However, WT1 does not always conform to the TSG label, and some data indicate that WT1 enhances cell survival and proliferation, like an oncogene. Is WT1 a chameleon, functioning as either a TSG or an oncogene, depending on cellular context? Are these labels even appropriate for describing and understanding the function of WT1?

  7. Inhibitor of differentiation 4 (Id4 is a potential tumor suppressor in prostate cancer

    Directory of Open Access Journals (Sweden)

    Carey Jason PW

    2009-06-01

    Full Text Available Abstract Background Inhibitor of differentiation 4 (Id4, a member of the Id gene family is also a dominant negative regulator of basic helix loop helix (bHLH transcription factors. Some of the functions of Id4 appear to be unique as compared to its other family members Id1, Id2 and Id3. Loss of Id4 gene expression in many cancers in association with promoter hypermethylation has led to the proposal that Id4 may act as a tumor suppressor. In this study we provide functional evidence that Id4 indeed acts as a tumor suppressor and is part of a cancer associated epigenetic re-programming. Methods Data mining was used to demonstrate Id4 expression in prostate cancer. Methylation specific polymerase chain reaction (MSP analysis was performed to understand molecular mechanisms associated with Id4 expression in prostate cancer cell lines. The effect of ectopic Id4 expression in DU145 cells was determined by cell cycle analysis (3H thymidine incorporation and FACS, expression of androgen receptor, p53 and cyclin dependent kinase inhibitors p27 and p21 by a combination of RT-PCR, real time-PCR, western blot and immuno-cytochemical analysis. Results Id4 expression was down-regulated in prostate cancer. Id4 expression was also down-regulated in prostate cancer line DU145 due to promoter hyper-methylation. Ectopic Id4 expression in DU145 prostate cancer cell line led to increased apoptosis and decreased cell proliferation due in part by an S-phase arrest. In addition to S-phase arrest, ectopic Id4 expression in PC3 cells also resulted in prolonged G2/M phase. At the molecular level these changes were associated with increased androgen receptor (AR, p21, p27 and p53 expression in DU145 cells. Conclusion The results suggest that Id4 acts directly as a tumor suppressor by influencing a hierarchy of cellular processes at multiple levels that leads to a decreased cell proliferation and change in morphology that is possibly mediated through induction of previously

  8. Signalling through FOXP3 as an X-linked Tumor Suppressor

    Science.gov (United States)

    Katoh, Hiroto; Zheng, Pan; Liu, Yang

    2010-01-01

    The FOXP3 (forkhead box P3) gene is a member of forkhead winged helix family transcription factors and functions as both a transcriptional activator and a repressor. FOXP3 dysfunction is responsible for an X-linked autoimmune syndrome: immune dysregulation, polyendopathy, enterophathy, X-linked syndrome. In addition to its role as an essential transcription factor in regulatory T cells, the FOXP3 gene is an epithelial cell-intrinsic tumor suppressor for breast and prostate cancers. We will focus on the FOXP3 signalling pathway in epithelial cells and discuss how genetic and/or epigenetic inactivation of the FOXP3 contributes to the malignant transformation of cells. PMID:20678582

  9. Molecular studies on the function of tumor suppressor gene in gastrointestinal cancer

    International Nuclear Information System (INIS)

    Kim, You Cheoul

    1993-01-01

    Cancer of stomach, colon and liver are a group of the most common cancer in Korea. However, results with current therapeutic modalities are still unsatisfactory. The intensive efforts have been made to understand basic pathogenesis and to find better therapeutic tools for the treatment of this miserable disease. We studies the alteration of tumor suppressor gene in various Gastrointestinal cancer in Korea. Results showed that genetic alteration of Rb gene was in 83% of colorectal cancer. Our results suggest that genetic alteration of Rb gene is crucially involved in the tumorigenesis of colorectum in Korea. (Author)

  10. Expression of the p16{sup INK4a} tumor suppressor gene in rodent lung tumors

    Energy Technology Data Exchange (ETDEWEB)

    Swafford, D.S.; Tesfaigzi, J.; Belinsky, S.A.

    1995-12-01

    Aberrations on the short arm of chromosome 9 are among the earliest genetic changes in human cancer. p16{sup INK4a} is a candidate tumor suppressor gene that lies within human 9p21, a chromosome region associated with frequent loss of heterozygosity in human lung tumors. The p16{sup INK4a} protein functions as an inhibitor of cyclin D{sub 1}-dependent kinases that phosphorylate the retinoblastoma (Rb) tumor suppressor gene product enabling cell-cycle progression. Thus, overexpression of cyclin D{sub 1}, mutation of cyclin-dependent kinase genes, or loss of p16{sup INK4a} function, can all result in functional inactivation of Rb. Inactivation of Rb by mutation or deletion can result in an increase in p16{sup INK4a} transcription, suggesting that an increased p16{sup INK4a} expression in a tumor cell signals dysfunction of the pathway. The p16{sup (INK4a)} gene, unlike some tumor suppressor genes, is rarely inactivated by mutation. Instead, the expression of this gene is suppressed in some human cancers by hypermethylation of the CpG island within the first exon or by homozygous deletion: 686. Chromosome losses have been observed at 9p21 syntenic loci in tumors of the mouse and rat, two species often used as animal models for pulmonary carcinogenesis. Expression of p16{sup INK4a} is lost in some mouse tumor cell lines, often due to homozygous deletion. These observations indicate that p16{sup INK4a} dysfunction may play a role in the development of neoplasia in rodents as well as humans. The purpose of the current investigation was to define the extent to which p16{sup INK4a} dysfunction contributes to the development of rodent lung tumors and to determine the mechanism of inactivation of the gene. There is no evidence to suggest a loss of function of the p16{sup INK4a} tumor suppressor gene in these primary murine lung tumors by mutation, deletion, or methylation.

  11. AC-Chopper-Based Inrush Current Suppressor in a Wind Power Generation System with Squirrel-Cage Induction Machines

    Directory of Open Access Journals (Sweden)

    Sho Shibata

    2018-02-01

    Full Text Available This paper proposes the inrush current suppressor using an AC chopper in a large-capacity wind power generation system (WPGS with two squirrel-cage induction machines (SCIMs, which are switched over depending on the wind speed. The input side of the AC chopper is connected to the source in parallel. The output side of the AC chopper is connected in series with the SCIM through matching transformers. In the proposed inrush current suppressor, the output voltage of the AC chopper is the same as the receiving-end voltage before connecting the SCIM. By gradually decreasing the output voltage of the AC chopper, the applied voltage of the SCIM is gradually increased without the inrush current. The basic principle of the proposed inrush current suppressor is discussed in detail. A computer simulation is implemented to confirm the validity and practicability of the proposed inrush current suppressor using a power system computer-aided design/electromagnetic transients including DC (PSCAD/EMTDC. Simulation results demonstrate that the proposed inrush current suppressor can suppress the inrush current.

  12. Quantitative changes of main components of erythrocyte membranes which define architectonics of cells under pttg gene knockout

    Directory of Open Access Journals (Sweden)

    О. P. Kanyuka

    2014-04-01

    Full Text Available A pttg gene knockout affects the functional state of erythron in mice which could be associated with structural changes in the structure of erythrocyte membranes. The pttg gene knockout causes a significant modification of fatty acids composition of erythrocyte membrane lipids by reducing the content of palmitic acid and increasing of polyunsaturated fatty acids amount by 18%. Analyzing the erythrocyte surface architectonics of mice under pttg gene knockout, it was found that on the background of reduction of the functionally complete biconcave discs population one could observe an increase of the number of transformed cells at different degeneration stages. Researches have shown that in mice with a pttg gene knockout compared with a control group of animals cytoskeletal protein – β-spectrin was reduced by 17.03%. However, there is a reduction of membrane protein band 3 by 33.04%, simultaneously the content of anion transport protein band 4.5 increases by 35.2% and protein band 4.2 by 32.1%. The lectin blot analysis has helped to reveal changes in the structure of the carbohydrate determinants of ery­throcyte membrane glycoproteins under conditions of directed pttg gene inactivation, accompanied by changes in the type of communication, which joins the terminal residue in carbohydrate determinant of glycoproteins. Thus, a significant redistribution of protein and fatty acids contents in erythrocyte membranes that manifested in the increase of the deformed shape of red blood cells is observed under pttg gene knockout.

  13. Receptor for advanced glycation end products (RAGE) knockout reduces fetal dysmorphogenesis in murine diabetic pregnancy.

    Science.gov (United States)

    Ejdesjö, Andreas; Brings, Sebastian; Fleming, Thomas; Fred, Rikard G; Nawroth, Peter P; Eriksson, Ulf J

    2016-07-01

    The receptor for Advanced Glycation End products (RAGE) is implicated in the pathogenesis of diabetic complications, but its importance in diabetic embryopathy is unclear. We therefore investigated the role of RAGE in diabetic embryopathy using streptozotocin induced diabetes in female wild type (WT) C57Bl/6N and RAGE knockout C57Bl/6N (RAGE(-/-)) mice, mated with control males of the same genotype. Maternal diabetes induced more fetal resorption and malformation (facial skeleton, neural tube) in the WT than in the RAGE(-/-) fetuses. Maternal plasma glucose and methylgyoxal concentrations, as well as embryonic N(ε)-carboxymethyl-lysine (CML) levels were increased to the same extent in diabetic WT and RAGE(-/-) pregnancy. However, maternal diabetes induced increased fetal hepatic isoprostane 8-iso-PGF2α levels (oxidative stress marker) and embryonic activation of NFκB in WT only (not in RAGE(-/-) embryos). The association between RAGE knockout and diminished embryonic dysmorphogenesis in diabetic pregnancy suggests that embryonic RAGE activation is involved in diabetic embryopathy. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. One-neutron knockout from light neutron-rich nuclei at relativistic energies

    International Nuclear Information System (INIS)

    Rodriguez-Tajes, C.; Alvarez-Pol, H.; Benjamim, E.; Benlliure, J.; Caamano, M.; Casarejos, E.; Cortina-Gil, D.; Gascon, M.; Kurtukian, T.; Perez-Loureiro, D.; Aumann, T.; Chatillon, A.; Geissel, H.; Nociforo, C.; Prochazka, A.; Simon, H.; Suemmerer, K.; Weick, H.; Winkler, M.; Borge, M. J. G.

    2010-01-01

    One-neutron knockout reactions from neutron-rich nuclei, with Z=6-13 and N=8-22, were studied at the Fragment Separator (GSI) at high beam energies, around 700 MeV/nucleon. Structural phenomena such as the formation of one-neutron halos in odd-mass carbon isotopes ( 15,17,19 C) will be discussed. In addition, one-neutron knockout measurements from 22 N were carried out for the first time and demonstrate clearly the change from a 0d 5/2 to a 1s 1/2 orbital for the valence neutron, an effect that is expected above N=14 and that was also observed in 23 O and 24 F. The possibility of an anomalous structure of 26 F, due to a significant 1s 1/2 neutron admixture, will also be discussed in the light of the experimental data obtained in this work. Finally, the ground-state configuration of neutron-rich neon isotopes ( 24-28 Ne) was studied, providing new information in a region that is relatively close to the island of inversion.

  15. Endothelin-1 Overexpression Improves Renal Function in eNOS Knockout Mice

    Directory of Open Access Journals (Sweden)

    Oleg Tsuprykov

    2015-10-01

    Full Text Available Background/Aims: To investigate the renal phenotype under conditions of an activated renal ET-1 system in the status of nitric oxide deficiency, we compared kidney function and morphology in wild-type, ET-1 transgenic (ET+/+, endothelial nitric oxide synthase knockout (eNOS-/- and ET+/+eNOS-/- mice. Methods: We assessed blood pressure, parameters of renal morphology, plasma cystatin C, urinary protein excretion, expression of genes associated with glomerular filtration barrier and tissue remodeling, and plasma metabolites using metabolomics. Results: eNOS-/- and ET+/+eNOS-/- mice developed hypertension. Osteopontin, albumin and protein excretion were increased in eNOS-/- and restored in ET+/+eNOS-/- animals. All genetically modified mice developed renal interstitial fibrosis and glomerulosclerosis. Genes involved in tissue remodeling (serpine1, TIMP1, Col1a1, CCL2 were up-regulated in eNOS-/-, but not in ET+/+eNOS-/- mice. Plasma levels of free carnitine and acylcarnitines, amino acids, diacyl phosphatidylcholines, lysophosphatidylcholines and hexoses were descreased in eNOS-/- and were in the normal range in ET+/+eNOS-/- mice. Conclusion: eNOS-/- mice developed renal dysfunction, which was partially rescued by ET-1 overexpression in eNOS-/- mice. The metabolomics results suggest that ET-1 overexpression on top of eNOS knockout is associated with a functional recovery of mitochondria (rescue effect in β-oxidation of fatty acids and an increase in antioxidative properties (normalization of monounsaturated fatty acids levels.

  16. Fmr1 and Nlgn3 knockout rats: novel tools for investigating autism spectrum disorders.

    Science.gov (United States)

    Hamilton, Shannon M; Green, Jennie R; Veeraragavan, Surabi; Yuva, Lisa; McCoy, Aaron; Wu, Yumei; Warren, Joe; Little, Lara; Ji, Diana; Cui, Xiaoxia; Weinstein, Edward; Paylor, Richard

    2014-04-01

    Animal models are critical for gaining insights into autism spectrum disorder (ASD). Despite their apparent advantages to mice for neural studies, rats have not been widely used for disorders of the human CNS, such as ASD, for the lack of convenient genome manipulation tools. Here we describe two of the first transgenic rat models for ASD, developed using zinc-finger nuclease (ZFN) methodologies, and their initial behavioral assessment using a rapid juvenile test battery. A syndromic and nonsyndromic rat model for ASD were created as two separate knockout rat lines with heritable disruptions in the genes encoding Fragile X mental retardation protein (FMRP) and Neuroligin3 (NLGN3). FMRP, a protein with numerous proposed functions including regulation of mRNA and synaptic protein synthesis, and NLGN3, a member of the neuroligin synaptic cell-adhesion protein family, have been implicated in human ASD. Juvenile subjects from both knockout rat lines exhibited abnormalities in ASD-relevant phenotypes including juvenile play, perseverative behaviors, and sensorimotor gating. These data provide important first evidence regarding the utility of rats as genetic models for investigating ASD-relevant genes.

  17. A Knockout Experiment: Disciplinary Divides and Experimental Skill in Animal Behaviour Genetics.

    Science.gov (United States)

    Nelson, Nicole C

    2015-07-01

    In the early 1990s, a set of new techniques for manipulating mouse DNA allowed researchers to 'knock out' specific genes and observe the effects of removing them on a live mouse. In animal behaviour genetics, questions about how to deploy these techniques to study the molecular basis of behaviour became quite controversial, with a number of key methodological issues dissecting the interdisciplinary research field along disciplinary lines. This paper examines debates that took place during the 1990s between a predominately North American group of molecular biologists and animal behaviourists around how to design, conduct, and interpret behavioural knockout experiments. Drawing from and extending Harry Collins's work on how research communities negotiate what counts as a 'well-done experiment,' I argue that the positions practitioners took on questions of experimental skill reflected not only the experimental traditions they were trained in but also their differing ontological and epistemological commitments. Different assumptions about the nature of gene action, eg., were tied to different positions in the knockout mouse debates on how to implement experimental controls. I conclude by showing that examining representations of skill in the context of a community's knowledge commitments sheds light on some of the contradictory ways in which contemporary animal behaviour geneticists talk about their own laboratory work as a highly skilled endeavour that also could be mechanised, as easy to perform and yet difficult to perform well.

  18. Necroptotic Cell Death Signaling and Execution Pathway: Lessons from Knockout Mice

    Directory of Open Access Journals (Sweden)

    José Belizário

    2015-01-01

    Full Text Available Under stress conditions, cells in living tissue die by apoptosis or necrosis depending on the activation of the key molecules within a dying cell that either transduce cell survival or death signals that actively destroy the sentenced cell. Multiple extracellular (pH, heat, oxidants, and detergents or intracellular (DNA damage and Ca2+ overload stress conditions trigger various types of the nuclear, endoplasmic reticulum (ER, cytoplasmatic, and mitochondrion-centered signaling events that allow cells to preserve the DNA integrity, protein folding, energetic, ionic and redox homeostasis, thus escaping from injury. Along the transition from reversible to irreversible injury, death signaling is highly heterogeneous and damaged cells may engage autophagy, apoptotic, or necrotic cell death programs. Studies on multiple double- and triple- knockout mice identified caspase-8, flip, and fadd genes as key regulators of embryonic lethality and inflammation. Caspase-8 has a critical role in pro- and antinecrotic signaling pathways leading to the activation of receptor interacting protein kinase 1 (RIPK1, RIPK3, and the mixed kinase domain-like (MLKL for a convergent execution pathway of necroptosis or regulated necrosis. Here we outline the recent discoveries into how the necrotic cell death execution pathway is engaged in many physiological and pathological outcome based on genetic analysis of knockout mice.

  19. Characterization of nasal potential difference in cftr knockout and F508del-CFTR mice.

    Directory of Open Access Journals (Sweden)

    Emilie Lyne Saussereau

    Full Text Available BACKGROUND: Treatments designed to correct cystic fibrosis transmembrane conductance regulator (CFTR defects must first be evaluated in preclinical experiments in the mouse model of cystic fibrosis (CF. Mice nasal mucosa mimics the bioelectric defect seen in humans. The use of nasal potential difference (V(TE to assess ionic transport is a powerful test evaluating the restoration of CFTR function. Nasal V(TE in CF mice must be well characterized for correct interpretation. METHODS: We performed V(TE measurements in large-scale studies of two mouse models of CF--B6;129 cftr knockout and FVB F508del-CFTR--and their respective wild-type (WT littermates. We assessed the repeatability of the test for cftr knockout mice and defined cutoff points distinguishing between WT and F508del-CFTR mice. RESULTS: We determined the typical V(TE values for CF and WT mice and demonstrated the existence of residual CFTR activity in F508del-CFTR mice. We characterized intra-animal variability in B6;129 mice and defined the cutoff points for F508del-CFTR chloride secretion rescue. Hyperpolarization of more than -2.15 mV after perfusion with a low-concentration Cl(- solution was considered to indicate a normal response. CONCLUSIONS: These data will make it possible to interpret changes in nasal V(TE in mouse models of CF, in future preclinical studies.

  20. Characterization of TG2 and TG1-TG2 double knock-out mouse epidermis.

    Science.gov (United States)

    Pitolli, Consuelo; Pietroni, Valentina; Marekov, Lyuben; Terrinoni, Alessandro; Yamanishi, Kiyofumi; Mazzanti, Cinzia; Melino, Gerry; Candi, Eleonora

    2017-03-01

    Transglutaminases (TGs) are a family of enzymes that catalyse the formation of isopeptide bonds between the γ-carboxamide groups of glutamine residues and the ε-amino groups of lysine residues leading to cross-linking reactions among proteins. Four members, TG1, TG2, TG3, and TG5, of the nine mammalian enzymes are expressed in the skin. TG1, TG3 and TG5 crosslinking properties are fundamental for cornified envelope assembly. In contrast, the role of TG2 in keratinization has never been studied at biochemical level in vivo. In this study, taking advantage of the TG2 knock-out (KO) and TG1 heterozygous mice, we generated and characterized the epidermis of TG1-TG2 double knock-out (DKO) mice. We performed morphological analysis of the epidermis and evaluation of the expression of differentiation markers. In addition, we performed analysis of the amino acid composition from isolated corneocytes. We found a significant change in amino acid composition in TG1KO cornified cell envelopes (CEs) while TG2KO amino acid composition was similar to wild-type CEs. Our results confirm a key role of TG1 in skin differentiation and CE assembly and demonstrate that TG2 is not essential for CE assembly and skin formation.

  1. Phenotypic screening of hepatocyte nuclear factor (HNF) 4-γ receptor knockout mice

    International Nuclear Information System (INIS)

    Gerdin, Anna Karin; Surve, Vikas V.; Joensson, Marie; Bjursell, Mikael; Bjoerkman, Maria; Edenro, Anne; Schuelke, Meint; Saad, Alaa; Bjurstroem, Sivert; Lundgren, Elisabeth Jensen; Snaith, Michael; Fransson-Steen, Ronny; Toernell, Jan; Berg, Anna-Lena; Bohlooly-Y, Mohammad

    2006-01-01

    Using the mouse as a model organism in pharmaceutical research presents unique advantages as its physiology in many ways resembles the human physiology, it also has a relatively short generation time, low breeding and maintenance costs, and is available in a wide variety of inbred strains. The ability to genetically modify mouse embryonic stem cells to generate mouse models that better mimic human disease is another advantage. In the present study, a comprehensive phenotypic screening protocol is applied to elucidate the phenotype of a novel mouse knockout model of hepatocyte nuclear factor (HNF) 4-γ. HNF4-γ is expressed in the kidneys, gut, pancreas, and testis. First level of the screen is aimed at general health, morphologic appearance, normal cage behaviour, and gross neurological functions. The second level of the screen looks at metabolic characteristics and lung function. The third level of the screen investigates behaviour more in-depth and the fourth level consists of a thorough pathological characterisation, blood chemistry, haematology, and bone marrow analysis. When compared with littermate wild-type mice (HNF4-γ +/+ ), the HNF4-γ knockout (HNF4-γ -/- ) mice had lowered energy expenditure and locomotor activity during night time that resulted in a higher body weight despite having reduced intake of food and water. HNF4-γ -/- mice were less inclined to build nest and were found to spend more time in a passive state during the forced swim test

  2. Molecular mechanisms of liver ischemia reperfusion injury: Insights from transgenic knockout models

    Science.gov (United States)

    Datta, Gourab; Fuller, Barry J; Davidson, Brian R

    2013-01-01

    Ischemia reperfusion injury is a major obstacle in liver resection and liver transplantation surgery. Understanding the mechanisms of liver ischemia reperfusion injury (IRI) and developing strategies to counteract this injury will therefore reduce acute complications in hepatic resection and transplantation, as well as expanding the potential pool of usable donor grafts. The initial liver injury is initiated by reactive oxygen species which cause direct cellular injury and also activate a cascade of molecular mediators leading to microvascular changes, increased apoptosis and acute inflammatory changes with increased hepatocyte necrosis. Some adaptive pathways are activated during reperfusion that reduce the reperfusion injury. IRI involves a complex interplay between neutrophils, natural killer T-cells cells, CD4+ T cell subtypes, cytokines, nitric oxide synthases, haem oxygenase-1, survival kinases such as the signal transducer and activator of transcription, Phosphatidylinositol 3-kinases/Akt and nuclear factor κβ pathways. Transgenic animals, particularly genetic knockout models, have become a powerful tool at elucidating mechanisms of liver ischaemia reperfusion injury and are complementary to pharmacological studies. Targeted disruption of the protein at the genetic level is more specific and maintained than pharmacological inhibitors or stimulants of the same protein. This article reviews the evidence from knockout models of liver IRI about the cellular and molecular mechanisms underlying liver IRI. PMID:23555157

  3. Application of Monoclonal Antibodies against Bioactive Natural Products: Eastern Blotting and Preparation of Knockout Extract

    Directory of Open Access Journals (Sweden)

    Hiroyuki Tanaka

    2012-01-01

    Full Text Available Matrix-assisted laser desorption/ionization (MALDI tof mass spectrometry was used for the confirmation of hapten number in synthesized antigen. As application of MAb, the MAbs against ginsenosides and glycyrrhizin have been prepared resulting in the development of two new techniques that we named the eastern blotting method and the knockout extract preparation. In eastern blotting technique, glycosides like ginsenosides and glycyrrhizin separated by silica gel TLC were blotted to PVDF membrane that was treated with a NaIO4 solution followed by BSA resulted in glycoside-BSA conjugate on a PVDF membrane. The blotted spots were stained by MAb. Double staining of eastern blotting for ginsenosides using antiginsenoside Rb1 and Rg1 MAbs promoted complete identification of ginsenosides in Panax species. The immunoaffinity concentration of glycyrrhizin was determined by immunoaffinity column conjugated with antiglycyrrhizin MAb resulting in the glycyrrhizin-knockout extract, which was determined by the synergic effect with glycyrrhizin on NO production using the cell line.

  4. Idebenone and resveratrol extend lifespan and improve motor function of HtrA2 knockout mice.

    Directory of Open Access Journals (Sweden)

    Ellen Gerhardt

    Full Text Available Heterozygous loss-of-function mutation of the human gene for the mitochondrial protease HtrA2 has been associated with increased risk to develop mitochondrial dysfunction, a process known to contribute to neurodegenerative disorders such as Huntington's disease (HD and Parkinson's disease (PD. Knockout of HtrA2 in mice also leads to mitochondrial dysfunction and to phenotypes that resemble those found in neurodegenerative disorders and, ultimately, lead to death of animals around postnatal day 30. Here, we show that Idebenone, a synthetic antioxidant of the coenzyme Q family, and Resveratrol, a bioactive compound extracted from grapes, are both able to ameliorate this phenotype. Feeding HtrA2 knockout mice with either compound extends lifespan and delays worsening of the motor phenotype. Experiments conducted in cell culture and on brain tissue of mice revealed that each compound has a different mechanism of action. While Idebenone acts by downregulating the integrated stress response, Resveratrol acts by attenuating apoptosis at the level of Bax. These activities can account for the delay in neuronal degeneration in the striata of these mice and illustrate the potential of these compounds as effective therapeutic approaches against neurodegenerative disorders such as HD or PD.

  5. Quasi-free one nucleon knockout reactions on neutron-rich oxygen isotopes

    Energy Technology Data Exchange (ETDEWEB)

    Atar, Leyla; Aumann, Thomas [TU Darmstadt, Darmstadt (Germany); GSI, Darmstadt (Germany); Bertulani, Carlos [Texas A and M University-Commerce, Commerse (United States); Paschalis, Stefanos [TU Darmstadt, Darmstadt (Germany); Nociforo, Chiara [GSI, Darmstadt (Germany); Collaboration: R3B-Collaboration

    2015-07-01

    Recent experiments have shown a reduction of spectroscopic strengths to about 60-70% for stable nuclei. When going to drip lines this tendency is changing, loosely bound nucleons have spectroscopic strengths close unity while deeply bound nucleons have a large reduction of the strength. We aim to make a systematic study of spectroscopic factors (SF) of the Oxygen isotopes using quasi-free (p,2p) and (p,pn) knockout reactions in inverse kinematics. Quasi-free knockout reactions are a direct tool to study the occupancy and the location of valance and deeply bound single particle states. The Oxygen isotopes offer a large variation of separation energies which will allow us to obtain a qualitative and quantitative understanding of SF in a large variation of isospin asymmetry. For this we performed an experiment at the R3B-LAND setup at the GSI with secondary beams containing {sup 14-24}O. The {sup 16-18}O and {sup 21-23}O isotopes have been analyzed and the preliminary results will be presented. The results include the partial cross sections, gamma ray spectra of the residual fragments in coincidence, and the SF obtained via comparison with theory.

  6. Phenotypic screening of hepatocyte nuclear factor (HNF) 4-gamma receptor knockout mice.

    Science.gov (United States)

    Gerdin, Anna Karin; Surve, Vikas V; Jönsson, Marie; Bjursell, Mikael; Björkman, Maria; Edenro, Anne; Schuelke, Meint; Saad, Alaa; Bjurström, Sivert; Lundgren, Elisabeth Jensen; Snaith, Michael; Fransson-Steen, Ronny; Törnell, Jan; Berg, Anna-Lena; Bohlooly-Y, Mohammad

    2006-10-20

    Using the mouse as a model organism in pharmaceutical research presents unique advantages as its physiology in many ways resembles the human physiology, it also has a relatively short generation time, low breeding and maintenance costs, and is available in a wide variety of inbred strains. The ability to genetically modify mouse embryonic stem cells to generate mouse models that better mimic human disease is another advantage. In the present study, a comprehensive phenotypic screening protocol is applied to elucidate the phenotype of a novel mouse knockout model of hepatocyte nuclear factor (HNF) 4-gamma. HNF4-gamma is expressed in the kidneys, gut, pancreas, and testis. The first level of the screen is aimed at general health, morphologic appearance, normal cage behaviour, and gross neurological functions. The second level of the screen looks at metabolic characteristics and lung function. The third level of the screen investigates behaviour more in-depth and the fourth level consists of a thorough pathological characterisation, blood chemistry, haematology, and bone marrow analysis. When compared with littermate wild-type mice (HNF4-gamma(+/+)), the HNF4-gamma knockout (HNF4-gamma(-/-)) mice had lowered energy expenditure and locomotor activity during night time that resulted in a higher body weight despite having reduced intake of food and water. HNF4-gamma(-/-) mice were less inclined to build nest and were found to spend more time in a passive state during the forced swim test.

  7. Characterization of a Bacillus subtilis surfactin synthetase knockout and antimicrobial activity analysis.

    Science.gov (United States)

    Liu, Hongxia; Qu, Xiaoxu; Gao, Ling; Zhao, Shengming; Lu, Zhaoxin; Zhang, Chong; Bie, Xiaomei

    2016-11-10

    Gene knockout is an important approach to improve the production of antimicrobial compounds. B. subtilis PB2-LS10, derived from B. subtilis PB2-L by a surfactin synthetase (srf) genes knockout, exhibits stronger inhibitory action than its parental strain against all tested pathogenic bacteria and fungi. The antimicrobial extracts produced by B. subtilis PB2-L and B. subtilis PB2-LS10 respectively were characterized by the high-resolution LC-ESI-MS. To provide further insight into the distinct antimicrobial activities, we investigated the impact of the srf genes deletion on the growth and gene transcriptional profile of the strains. The mutant strain grew quickly and reached stationary phase 2h earlier than the wild-type. Prominent expression changes in the modified strain involved genes that were essential to metabolic pathways and processes. Genes related to amino acid transport, ATP-binding cassette (ABC) transporters and protein export were up-regulated in strain PB2-LS10. However, amino acid metabolism, carbohydrate metabolism and fatty acid metabolism were repressed. Because of its excellent antimicrobial activity, strain PB2-LS10 has potential for use in food preservation. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. Obese Neuronal PPARγ Knockout Mice Are Leptin Sensitive but Show Impaired Glucose Tolerance and Fertility.

    Science.gov (United States)

    Fernandez, Marina O; Sharma, Shweta; Kim, Sun; Rickert, Emily; Hsueh, Katherine; Hwang, Vicky; Olefsky, Jerrold M; Webster, Nicholas J G

    2017-01-01

    The peroxisome-proliferator activated receptor γ (PPARγ) is expressed in the hypothalamus in areas involved in energy homeostasis and glucose metabolism. In this study, we created a deletion of PPARγ brain-knockout (BKO) in mature neurons in female mice to investigate its involvement in metabolism and reproduction. We observed that there was no difference in age at puberty onset between female BKOs and littermate controls, but the BKOs gave smaller litters when mated and fewer oocytes when ovulated. The female BKO mice had regular cycles but showed an increase in the number of cycles with prolonged estrus. The mice also had increased luteinizing hormone (LH) levels during the LH surge and histological examination showed hemorrhagic corpora lutea. The mice were challenged with a 60% high-fat diet (HFD). Metabolically, the female BKO mice showed normal body weight, glucose and insulin tolerance, and leptin levels but were protected from obesity-induced leptin resistance. The neuronal knockout also prevented the reduction in estrous cycles due to the HFD. Examination of ovarian histology showed a decrease in the number of primary and secondary follicles in both genotypes due to the HFD, but the BKO ovaries showed an increase in the number of hemorrhagic follicles. In summary, our results show that neuronal PPARγ is required for optimal female fertility but is also involved in the adverse effects of diet-induced obesity by creating leptin resistance potentially through induction of the repressor Socs3. Copyright © 2017 by the Endocrine Society.

  9. Obesity occurring in apolipoprotein E-knockout mice has mild effects on fertility.

    Science.gov (United States)

    Zhang, Ting; Dai, Pengyuan; Cheng, Dong; Zhang, Liang; Chen, Zijiang; Meng, Xiaoqian; Zhang, Fumiao; Han, Xiaoying; Liu, Jianwei; Pan, Jie; Yang, Guiwen; Zhang, Cong

    2014-02-01

    The Apolipoprotein (Apo) family is implicated in lipid metabolism. There are five types of Apo: Apoa, Apob, Apoc, Apod, and Apoe. Apoe has been demonstrated to play a central role in lipoprotein metabolism and to be essential for efficient receptor-mediated plasma clearance of chylomicron remnants and VLDL remnant particles by the liver. Apoe-deficient (Apoe(-/-)) mice develop atherosclerotic plaques spontaneously, followed by obesity. In this study, we investigated whether lipid deposition caused by Apoe knockout affects reproduction in female mice. The results demonstrated that Apoe(-/-) mice were severely hypercholesterolemic, with their cholesterol metabolism disordered, and lipid accumulating in the ovaries causing the ovaries to be heavier compared with the WT counterparts. In addition, estrogen and progesterone decreased significantly at D 100. Quantitative PCR analysis demonstrated that at D 100 the expression of cytochromeP450 aromatase (Cyp19a1), 3β-hydroxysteroid dehydrogenase (Hsd3b), mechanistic target of rapamycin (Mtor), and nuclear factor-κB (Nfkb) decreased significantly, while that of BCL2-associated agonist of cell death (Bad) and tuberous sclerosis complex 2 (Tsc2) increased significantly in the Apoe(-/-) mice. However, there was no difference in the fertility rates of the Apoe(-/-) and WT mice; that is, obesity induced by Apoe knockout has no significant effect on reproduction. However, the deletion of Apoe increased the number of ovarian follicles and the ratio of ovarian follicle atresia and apoptosis. We believe that this work will augment our understanding of the role of Apoe in reproduction.

  10. Effects of major histocompatibility complex class II knockout on mouse bone mechanical properties during development

    Science.gov (United States)

    Simske, Steven J.; Bateman, Ted A.; Smith, Erin E.; Ferguson, Virginia L.; Chapes, Stephen K.

    2002-01-01

    We investigated the effect of major histocompatibility complex class II (MHC II) knockout on the development of the mouse peripheral skeleton. These C2D mice had less skeletal development at 8, 12 and 16 weeks of age compared to wild-type C57BL/6J (B6) male mice. The C2D mice had decreased femur mechanical, geometric and compositional measurements compared to wild type mice at each of these ages. C2D femur stiffness (S), peak force in 3-pt bending (Pm), and mineral mass (Min-M) were 74%, 64% and 66%, respectively, of corresponding B6 values at 8 weeks of age. Similar differences were measured at 12 weeks (for which C2D femoral S, Pm and Min-M were 71%, 72% and 73%, respectively, of corresponding B6 values) and at 16 weeks (for which C2D femoral S, Pm and Min-M were 80%, 66% and 61%, respectively, of corresponding B6 values). MHC II knockout delays the development of adult bone properties and is accompanied by lower body mass compared to wild-type controls.

  11. Generation of protein-specific and alloantigen-specific suppressor cells following total lymphoid irradiation in mice

    International Nuclear Information System (INIS)

    Slavin, S.; Zan-Bar, I.; Strober, S.

    1979-01-01

    The presence of donor-type specific suppressor cells was demonstrated in C57BL/Ka → BALB/c BM chimeras in both in vivo and in vitro experiments. In both experiments tolerance to either BSA of C57BL/Ka tissue antigens could be transferred into adoptive recipients. In view of the data obtained in BSA-tolerant mice, it is likely that the suppressor cells in the chimeras were also T cells in origin; however, formal proof has yet to be obtained. We conclude that antigen-specific suppressor cells are generated following TLI. Specific transplantation tolerance obtained by immunomanipulation rather than by prolonged use of nonspecific immunosuppressive agents is the goal of clinical BM and organ transplantation. Due to the experience accumulated in patients with Hodgkin's disease regarding the effects and relative safety of using TLI, it may soon become a new clinical tool for BM and organ transplantation in man

  12. Characteristics of Suppressor Macrophages Induced by Mycobacterial and Protozoal Infections in relation to Alternatively Activated M2 Macrophages

    Directory of Open Access Journals (Sweden)

    Haruaki Tomioka

    2012-01-01

    Full Text Available In the advanced stages of mycobacterial infections, host immune systems tend to change from a Th1-type to Th2-type immune response, resulting in the abrogation of Th1 cell- and macrophage-mediated antimicrobial host protective immunity. Notably, this type of immune conversion is occasionally associated with the generation of certain types of suppressor macrophage populations. During the course of Mycobacterium tuberculosis (MTB and Mycobacterium avium-intracellulare complex (MAC infections, the generation of macrophages which possess strong suppressor activity against host T- and B-cell functions is frequently encountered. This paper describes the immunological properties of M1- and M2-type macrophages generated in tumor-bearing animals and those generated in hosts with certain microbial infections. In addition, this paper highlights the immunological and molecular biological characteristics of suppressor macrophages generated in hosts with mycobacterial infections, especially MAC infection.

  13. NNK, a Tobacco-Specific Carcinogen, Inhibits the Expression of Lysyl Oxidase, a Tumor Suppressor

    Directory of Open Access Journals (Sweden)

    Guang Cheng

    2014-12-01

    Full Text Available A tobacco-specific carcinogen, 4-(methylnitrosamino-1-(3-pyridyl-1-butanone (NNK, is believed to contribute to the cancer burden in cigarette smokers. To evaluate NNK effects on the expression of lysyl oxidase (LOX, a tumor suppressor, we examined this enzyme at various levels in NNK-treated rat fetal lung fibroblasts (RFL6. Exposure of cells to NNK reduced levels of steady-states LOX mRNA and new transcript synthesis. NNK inhibited all LOX protein species in a dose-dependent manner. Although 300 µM NNK markedly decreased the level in the 46 kDa preproenzyme, under same conditions, there was no detectable amounts of the 50 kDa proenzyme and the 32 kDa mature enzyme suggesting NNK perturbing the LOX protein processing to its mature form. Moreover, NNK also suppressed LOX activities in conditioned media of treated cells. At the promoter level, NNK enhanced methylation of CpG, but decreased acetylation of histone H3 at the core promoter region of the LOX gene. These results indicated that transcriptional and translational processes of LOX are major targets for NNK. Thus, inactivation of tumor suppressor gene LOX may play a critical role in NNK carcinogenesis.

  14. Src Inhibits the Hippo Tumor Suppressor Pathway through Tyrosine Phosphorylation of Lats1.

    Science.gov (United States)

    Si, Yuan; Ji, Xinyan; Cao, Xiaolei; Dai, Xiaoming; Xu, Lingyi; Zhao, Hongxia; Guo, Xiaocan; Yan, Huan; Zhang, Haitao; Zhu, Chu; Zhou, Qi; Tang, Mei; Xia, Zongping; Li, Li; Cong, Yu-Sheng; Ye, Sheng; Liang, Tingbo; Feng, Xin-Hua; Zhao, Bin

    2017-09-15

    The Hippo pathway regulates cell proliferation, apoptosis, and stem cell self-renewal, and its inactivation in animal models causes organ enlargement followed by tumorigenesis. Hippo pathway deregulation occurs in many human cancers, but the underlying mechanisms are not fully understood. Here, we report tyrosine phosphorylation of the Hippo pathway tumor suppressor LATS1 as a mechanism underlying its regulation by cell adhesion. A tyrosine kinase library screen identified Src as the kinase to directly phosphorylate LATS1 on multiple residues, causing attenuated Mob kinase activator binding and structural alteration of the substrate-binding pocket in the kinase domain. Cell matrix adhesion activated the Hippo pathway effector transcription coactivator YAP partially through Src-mediated phosphorylation and inhibition of LATS1. Aberrant Src activation abolished the tumor suppressor activity of LATS1 and induced tumorigenesis in a YAP-dependent manner. Protein levels of Src in human breast cancer tissues correlated with accumulation of active YAP dephosphorylated on the LATS1 target site. These findings reveal tyrosine phosphorylation of LATS1 by Src as a novel mechanism of Hippo pathway regulation by cell adhesion and suggest Src activation as an underlying reason for YAP deregulation in tumorigenesis. Cancer Res; 77(18); 4868-80. ©2017 AACR . ©2017 American Association for Cancer Research.

  15. Simultaneous loss of the DLC1 and PTEN tumor suppressors enhances breast cancer cell migration

    International Nuclear Information System (INIS)

    Heering, Johanna; Erlmann, Patrik; Olayioye, Monilola A.

    2009-01-01

    The phosphatase and tensin homolog (PTEN) gene is a tumor suppressor frequently deleted or mutated in sporadic tumors of the breast, prostate, endometrium and brain. The protein acts as a dual specificity phosphatase for lipids and proteins. PTEN loss confers a growth advantage to cells, protects from apoptosis and favors cell migration. The deleted in liver cancer 1 (DLC1) gene has emerged as a novel tumor suppressor downregulated in a variety of tumor types including those of the breast. DLC1 contains a Rho GTPase activating domain that is involved in the inhibition of cell proliferation, migration and invasion. To investigate how simultaneous loss of PTEN and DLC1 contributes to cell transformation, we downregulated both proteins by RNA interference in the non-invasive MCF7 breast carcinoma cell line. Joint depletion of PTEN and DLC1 resulted in enhanced cell migration in wounding and chemotactic transwell assays. Interestingly, both proteins were found to colocalize at the plasma membrane and interacted physically in biochemical pulldowns and coimmunoprecipitations. We therefore postulate that the concerted local inactivation of signaling pathways downstream of PTEN and DLC1, respectively, is required for the tight control of cell migration.

  16. Simultaneous loss of the DLC1 and PTEN tumor suppressors enhances breast cancer cell migration

    Energy Technology Data Exchange (ETDEWEB)

    Heering, Johanna; Erlmann, Patrik [University of Stuttgart, Institute of Cell Biology and Immunology, Allmandring 31, 70569 Stuttgart (Germany); Olayioye, Monilola A., E-mail: monilola.olayioye@izi.uni-stuttgart.de [University of Stuttgart, Institute of Cell Biology and Immunology, Allmandring 31, 70569 Stuttgart (Germany)

    2009-09-10

    The phosphatase and tensin homolog (PTEN) gene is a tumor suppressor frequently deleted or mutated in sporadic tumors of the breast, prostate, endometrium and brain. The protein acts as a dual specificity phosphatase for lipids and proteins. PTEN loss confers a growth advantage to cells, protects from apoptosis and favors cell migration. The deleted in liver cancer 1 (DLC1) gene has emerged as a novel tumor suppressor downregulated in a variety of tumor types including those of the breast. DLC1 contains a Rho GTPase activating domain that is involved in the inhibition of cell proliferation, migration and invasion. To investigate how simultaneous loss of PTEN and DLC1 contributes to cell transformation, we downregulated both proteins by RNA interference in the non-invasive MCF7 breast carcinoma cell line. Joint depletion of PTEN and DLC1 resulted in enhanced cell migration in wounding and chemotactic transwell assays. Interestingly, both proteins were found to colocalize at the plasma membrane and interacted physically in biochemical pulldowns and coimmunoprecipitations. We therefore postulate that the concerted local inactivation of signaling pathways downstream of PTEN and DLC1, respectively, is required for the tight control of cell migration.

  17. Immunopurification of the suppressor tRNA dependent rabbit β-globin readthrough protein

    International Nuclear Information System (INIS)

    Hatfield, D.; Thorgeirsson, S.S.; Copeland, T.D.; Oroszlan, S.; Bustin, M.

    1988-01-01

    In mammalian cells, the rabbit β-globin readthrough protein is the only known example of a naturally occurring readthrough protein which does not involve a viral system. To provide an efficient means for its isolation, detection, and study, the authors elicited specific antibodies against this unique protein. The 22 amino acid peptide corresponding to the readthrough portion of this protein was synthesized, coupled to keyhole limpet hemocyanin, and injected into sheep. Specific antibodies to the peptide were produced as demonstrated by the enzyme-linked immunosorbent assay technique and by immunoblotting. The antibodies did not react with globin. The rabbit β-globin readthrough protein was separated from globin and other reticulocyte proteins by polyacrylamide gel electrophoresis and visualized by silver staining or by labeling with [ 35 S] methionine. Incorporation of [ 35 S] methionine into the readthrough protein was significantly enhanced upon addition of an opal suppressor tRNA to reticulocyte lysates. Immunoblotting revealed that the readthrough protein also occurs in lysates without added suppressor tRNA. The antibodies were purified on an affi-gel column which had been coupled with the peptide antigen. The readthrough protein was then purified from reticulocytes by immunoaffinity chromatography and by high-performance liquid chromatography. The results provide conclusive evidence that the β-globin readthrough protein is naturally occurring in rabbit reticulocytes

  18. Biochemical and genetic functional dissection of the P38 viral suppressor of RNA silencing.

    Science.gov (United States)

    Iki, Taichiro; Tschopp, Marie-Aude; Voinnet, Olivier

    2017-05-01

    Phytoviruses encode viral suppressors of RNA silencing (VSRs) to counteract the plant antiviral silencing response, which relies on virus-derived small interfering (si)RNAs processed by Dicer RNaseIII enzymes and subsequently loaded into ARGONAUTE (AGO) effector proteins. Here, a tobacco cell-free system was engineered to recapitulate the key steps of antiviral RNA silencing and, in particular, the most upstream double-stranded (ds)RNA processing reaction, not kinetically investigated thus far in the context of plant VSR studies. Comparative biochemical analyses of distinct VSRs in the reconstituted assay showed that in all cases tested, VSR interactions with siRNA duplexes inhibited the loading, but not the activity, of antiviral AGO1 and AGO2. Turnip crinkle virus P38 displayed the additional and unique property to bind both synthetic and RNA-dependent-RNA-polymerase-generated long dsRNAs, and inhibited the processing into siRNAs. Single amino acid substitutions in P38 could dissociate dsRNA-processing from AGO-loading inhibition in vitro and in vivo, illustrating dual-inhibitory strategies discriminatively deployed within a single viral protein, which, we further show, are bona fide suppressor functions that evolved independently of the conserved coat protein function of P38. © 2017 Iki et al.; Published by Cold Spring Harbor Laboratory Press for the RNA Society.

  19. The potyviral suppressor of RNA silencing confers enhanced resistance to multiple pathogens

    International Nuclear Information System (INIS)

    Pruss, Gail J.; Lawrence, Christopher B.; Bass, Troy; Li Qingshun Q.; Bowman, Lewis H.; Vance, Vicki

    2004-01-01

    Helper component-protease (HC-Pro) is a plant viral suppressor of RNA silencing, and transgenic tobacco expressing HC-Pro has increased susceptibility to a broad range of viral pathogens. Here we report that these plants also exhibit enhanced resistance to unrelated heterologous pathogens. Tobacco mosaic virus (TMV) infection of HC-Pro-expressing plants carrying the N resistance gene results in fewer and smaller lesions compared to controls without HC-Pro. The resistance to TMV is compromised but not eliminated by expression of nahG, which prevents accumulation of salicylic acid (SA), an important defense signaling molecule. HC-Pro-expressing plants are also more resistant to tomato black ring nepovirus (TBRV) and to the oomycete Peronospora tabacina. Enhanced TBRV resistance is SA-independent, whereas the response to P. tabacina is associated with early induction of markers characteristic of SA-dependent defense. Thus, a plant viral suppressor of RNA silencing enhances resistance to multiple pathogens via both SA-dependent and SA-independent mechanisms

  20. Axial-Symmetry Numerical Approaches for Noise Predicting and Attenuating of Rifle Shooting with Suppressors

    Directory of Open Access Journals (Sweden)

    Shi-Wei Lo

    2011-01-01

    Full Text Available The moving bullet out of a rifle barrel is propelled by a fired explosive charge. Subsequently, a disturbed muzzle blast wave is initiated which lasts several milliseconds. In this study, axially symmetric, unsteady, Large Eddy Simulation (LES, and Ffowcs Williams and Hawkins (FWH equations were solved by the implicit-time formulation. For the spatial discretization, second order upwind scheme was employed. In addition, dynamic mesh model was used to where the ballistic domain changed with time due to the motion of bullet. Results obtained for muzzle flow field and for noise recorded were compared with those obtained from experimental data; these two batches of results were in agreement. Five cases of gunshot including one model of an unsuppressed rifle and four models of suppressors were simulated. Besides, serial images of species distributions and velocity vectors-pressure contours in suppressors and near muzzle field were displayed. The sound pressure levels (dB in far field that were post-processed by the fast Fourier transform (FFT were compared. The proposed physical model and the numerical simulations used in the present work are expected to be extended to solve other shooting weapon problems with three-dimensional and complex geometries.

  1. Expansion of Myeloid-Derived Suppressor Cells in Patients with Acute Coronary Syndrome

    Directory of Open Access Journals (Sweden)

    Yan-ge Wang

    2015-01-01

    Full Text Available Aim: The aim of this study was to explore whether the circulating frequency and function of myeloid-derived suppressor cells (MDSCs are altered in patients with acute coronary syndrome (ACS. Methods: The frequency of MDSCs in peripheral blood was determined by flow cytometry, and mRNA expression in purified MDSCs was analyzed by real-time reverse transcription polymerase chain reaction (RT-PCR. The suppressive function of MDSCs isolated from different groups was also determined. The plasma levels of certain cytokines were determined using Bio-Plex Pro™ Human Cytokine Assays. Results: The frequency of circulating CD14+HLA-DR-/low MDSCs; arginase-1 (Arg-1 expression; and plasma levels of interleukin (IL-1β, IL-6, tumor necrosis factor (TNF-α, and IL-33 were markedly increased in ACS patients compared to stable angina (SA or control patients. Furthermore, MDSCs from ACS patients were more potent suppressors of T-cell proliferation and IFN-γ production than those from the SA or control groups at ratios of 1:4 and 1:2; this effect was partially mediated by Arg-1. In addition, the frequency of MDSCs was positively correlated with plasma levels of IL-6, IL-33, and TNF-α. Conclusions: We observed an increased frequency and suppressive function of MDSCs in ACS patients, a result that may provide insights into the mechanisms involved in ACS.

  2. The tumor suppressor Rb and its related Rbl2 genes are regulated by Utx histone demethylase

    Energy Technology Data Exchange (ETDEWEB)

    Terashima, Minoru; Ishimura, Akihiko; Yoshida, Masakazu [Division of Functional Genomics, Cancer Research Institute, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Ishikawa (Japan); Suzuki, Yutaka; Sugano, Sumio [Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa 277-8561, Chiba (Japan); Suzuki, Takeshi, E-mail: suzuki-t@staff.kanazawa-u.ac.jp [Division of Functional Genomics, Cancer Research Institute, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Ishikawa (Japan)

    2010-08-20

    Research highlights: {yields} Utx increases expression of Rb and Rbl2 genes through its demethylase activity. {yields} Utx changes histone H3 methylation on the Rb and Rbl2 promoters. {yields} Utx induces decreased cell proliferation of mammalian primary cells. -- Abstract: Utx is a candidate tumor suppressor gene that encodes histone H3 lysine 27 (H3K27) demethylase. In this study, we found that ectopic expression of Utx enhanced the expression of retinoblastoma tumor suppressor gene Rb and its related gene Rbl2. This activation was dependent on the demethylase activity of Utx, and was suggested to contribute to the decreased cell proliferation induced by Utx. A chromatin immunoprecipitation assay showed that over-expressed Utx was associated with the promoter regions of Rb and Rbl2 resulting in the removal of repressive H3K27 tri-methylation and the increase in active H3K4 tri-methylation. Furthermore, siRNA-mediated knockdown of Utx revealed the recruitment of endogenous Utx protein on the promoters of Rb and Rbl2 genes. These results indicate that Rb and Rbl2 are downstream target genes of Utx and may play important roles in Utx-mediated cell growth control.

  3. Unexpected functional similarities between gatekeeper tumour suppressor genes and proto-oncogenes revealed by systems biology.

    Science.gov (United States)

    Zhao, Yongzhong; Epstein, Richard J

    2011-05-01

    Familial tumor suppressor genes comprise two subgroups: caretaker genes (CTs) that repair DNA, and gatekeeper genes (GKs) that trigger cell death. Since GKs may also induce cell cycle delay and thus enhance cell survival by facilitating DNA repair, we hypothesized that the prosurvival phenotype of GKs could be selected during cancer progression, and we used a multivariable systems biology approach to test this. We performed multidimensional data analysis, non-negative matrix factorization and logistic regression to compare the features of GKs with those of their putative antagonists, the proto-oncogenes (POs), as well as with control groups of CTs and functionally unrelated congenital heart disease genes (HDs). GKs and POs closely resemble each other, but not CTs or HDs, in terms of gene structure (Pexpression level and breadth (Pimplied suggest a common functional attribute that is strongly negatively selected-that is, a shared phenotype that enhances cell survival. The counterintuitive finding of similar evolutionary pressures affecting GKs and POs raises an intriguing possibility: namely, that cancer microevolution is accelerated by an epistatic cascade in which upstream suppressor gene defects subvert the normal bifunctionality of wild-type GKs by constitutively shifting the phenotype away from apoptosis towards survival. If correct, this interpretation would explain the hitherto unexplained phenomenon of frequent wild-type GK (for example, p53) overexpression in tumors.

  4. Non-Aqueous Titration Method for Determining Suppressor Concentration in the MCU Next Generation Solvent (NGS)

    International Nuclear Information System (INIS)

    Taylor-Pashow, Kathryn M. L.; Jones, Daniel H.

    2017-01-01

    A non-aqueous titration method has been used for quantifying the suppressor concentration in the MCU solvent hold tank (SHT) monthly samples since the Next Generation Solvent (NGS) was implemented in 2013. The titration method measures the concentration of the NGS suppressor (TiDG) as well as the residual tri-n-octylamine (TOA) that is a carryover from the previous solvent. As the TOA concentration has decreased over time, it has become difficult to resolve the TiDG equivalence point as the TOA equivalence point has moved closer. In recent samples, the TiDG equivalence point could not be resolved, and therefore, the TiDG concentration was determined by subtracting the TOA concentration as measured by semi-volatile organic analysis (SVOA) from the total base concentration as measured by titration. In order to improve the titration method so that the TiDG concentration can be measured directly, without the need for the SVOA data, a new method has been developed that involves spiking of the sample with additional TOA to further separate the two equivalence points in the titration. This method has been demonstrated on four recent SHT samples and comparison to results obtained using the SVOA TOA subtraction method shows good agreement. Therefore, it is recommended that the titration procedure be revised to include the TOA spike addition, and this to become the primary method for quantifying the TiDG.

  5. Non-Aqueous Titration Method for Determining Suppressor Concentration in the MCU Next Generation Solvent (NGS)

    Energy Technology Data Exchange (ETDEWEB)

    Taylor-Pashow, Kathryn M. L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Jones, Daniel H. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2017-10-23

    A non-aqueous titration method has been used for quantifying the suppressor concentration in the MCU solvent hold tank (SHT) monthly samples since the Next Generation Solvent (NGS) was implemented in 2013. The titration method measures the concentration of the NGS suppressor (TiDG) as well as the residual tri-n-octylamine (TOA) that is a carryover from the previous solvent. As the TOA concentration has decreased over time, it has become difficult to resolve the TiDG equivalence point as the TOA equivalence point has moved closer. In recent samples, the TiDG equivalence point could not be resolved, and therefore, the TiDG concentration was determined by subtracting the TOA concentration as measured by semi-volatile organic analysis (SVOA) from the total base concentration as measured by titration. In order to improve the titration method so that the TiDG concentration can be measured directly, without the need for the SVOA data, a new method has been developed that involves spiking of the sample with additional TOA to further separate the two equivalence points in the titration. This method has been demonstrated on four recent SHT samples and comparison to results obtained using the SVOA TOA subtraction method shows good agreement. Therefore, it is recommended that the titration procedure be revised to include the TOA spike addition, and this to become the primary method for quantifying the TiDG.

  6. The Regulation of Tumor Suppressor p63 by the Ubiquitin-Proteasome System

    Directory of Open Access Journals (Sweden)

    Stephen R. Armstrong

    2016-12-01

    Full Text Available The protein p63 has been identified as a homolog of the tumor suppressor protein p53 and is capable of inducing apoptosis, cell cycle arrest, or senescence. p63 has at least six isoforms, which can be divided into two major groups: the TAp63 variants that contain the N-terminal transactivation domain and the ΔNp63 variants that lack the N-terminal transactivation domain. The TAp63 variants are generally considered to be tumor suppressors involved in activating apoptosis and suppressing metastasis. ΔNp63 variants cannot induce apoptosis but can act as dominant negative inhibitors to block the function of TAp53, TAp73, and TAp63. p63 is rarely mutated in human tumors and is predominately regulated at the post-translational level by phosphorylation and ubiquitination. This review focuses primarily on regulation of p63 by the ubiquitin E-3 ligase family of enzymes via ubiquitination and proteasome-mediated degradation, and introduces a new key regulator of the p63 protein.

  7. Warburg tumours and the mechanisms of mitochondrial tumour suppressor genes. Barking up the right tree?

    Science.gov (United States)

    Bayley, Jean-Pierre; Devilee, Peter

    2010-06-01

    The past decade has seen a revival of interest in the metabolic adaptations of tumours, named for their original discoverer, Otto Warburg. Warburg reported a high rate of glycolysis in tumours, and a concurrent defect in mitochondrial respiration. The rediscovery of Warburg's hypothesis coincided with the discovery of mitochondrial tumours suppressor genes that may conform to Warburg's hypothesis. Succinate dehydrogenase and fumarate hydratase are mitochondrial proteins of the TCA cycle and the respiratory chain and when mutated lead to tumours of the nervous system known as paragangliomas and pheochromocytomas, and in the case of fumarate hydratase, cutaneous and uterine leiomyomas and renal cell cancer. Recently a novel mitochondrial protein, SDHAF2 (SDH5), was also shown to be a paraganglioma-related tumour suppressor gene. Another mitochondrial and TCA cycle-related protein, isocitrate dehydrogenase 2 is, together with IDH1, frequently mutated in the brain tumour glioblastoma. There are currently many competing hypotheses on the role of these genes in tumourigenesis, but frequent themes are the stabilization of hypoxia inducible factor 1 and upregulation of genes involved in angiogenesis, glucose transport and glycolysis. Other postulated mechanisms include the inhibition of developmental apoptosis, altered gene expression due to histone deregulation and the acquisition of novel catalytic properties. Here we discuss these diverse hypotheses and highlight very recent findings on the possible effects of IDH gene mutations.

  8. Tumor Suppressor Genes within Common Fragile Sites Are Active Players in the DNA Damage Response.

    Directory of Open Access Journals (Sweden)

    Idit Hazan

    2016-12-01

    Full Text Available The role of common fragile sites (CFSs in cancer remains controversial. Two main views dominate the discussion: one suggests that CFS loci are hotspots of genomic instability leading to inactivation of genes encoded within them, while the other view proposes that CFSs are functional units and that loss of the encoded genes confers selective pressure, leading to cancer development. The latter view is supported by emerging evidence showing that expression of a given CFS is associated with genome integrity and that inactivation of CFS-resident tumor suppressor genes leads to dysregulation of the DNA damage response (DDR and increased genomic instability. These two viewpoints of CFS function are not mutually exclusive but rather coexist; when breaks at CFSs are not repaired accurately, this can lead to deletions by which cells acquire growth advantage because of loss of tumor suppressor activities. Here, we review recent advances linking some CFS gene products with the DDR, genomic instability, and carcinogenesis and discuss how their inactivation might represent a selective advantage for cancer cells.

  9. Myeloid-derived suppressor cells: paradoxical roles in infection and immunity.

    Science.gov (United States)

    Dai, Jun; El Gazzar, Mohamed; Li, Guang Y; Moorman, Jonathan P; Yao, Zhi Q

    2015-01-01

    Myeloid-derived suppressor cells (MDSCs) are a heterogeneous population of immature suppressor cells that are generated due to aberrant myelopoiesis under pathological conditions. Although MDSCs have been recognized for more than 20 years under the guise of different monikers, these particular populations of myeloid cells gained more attention recently due to their immunosuppressive properties, which halt host immune responses to growing cancers or overwhelming infections. While MDSCs may contribute to immune homeostasis after infection or tissue injury by limiting excessive inflammatory processes, their expansion may be at the expense of pathogen elimination and thus may lead to disease persistence. Therefore, MDSCs may be either damaging or obliging to the host by attenuating, for example, antitumor or anti-infectious immune responses. In this review, we recapitulate the biological and immunological aspects of MDSCs, including their generation, distribution, trafficking and the factors involved in their activation, expansion, suppressive functions, and interplay between MDSCs and regulatory T cells, with a focus on the perspectives of infection and inflammation. © 2014 S. Karger AG, Basel.

  10. SFRP Tumour Suppressor Genes Are Potential Plasma-Based Epigenetic Biomarkers for Malignant Pleural Mesothelioma

    Directory of Open Access Journals (Sweden)

    Yuen Yee Cheng

    2017-01-01

    Full Text Available Malignant pleural mesothelioma (MPM is associated with asbestos exposure. Asbestos can induce chronic inflammation which in turn can lead to silencing of tumour suppressor genes. Wnt signaling pathway can be affected by chronic inflammation and is aberrantly activated in many cancers including colon and MPM. SFRP genes are antagonists of Wnt pathway, and SFRPs are potential tumour suppressors in colon, gastric, breast, ovarian, and lung cancers and mesothelioma. This study investigated the expression and DNA methylation of SFRP genes in MPM cells lines with and without demethylation treatment. Sixty-six patient FFPE samples were analysed and have showed methylation of SFRP2 (56% and SFRP5 (70% in MPM. SFRP2 and SFRP5 tumour-suppressive activity in eleven MPM lines was confirmed, and long-term asbestos exposure led to reduced expression of the SFRP1 and SFRP2 genes in the mesothelium (MeT-5A via epigenetic alterations. Finally, DNA methylation of SFRPs is detectable in MPM patient plasma samples, with methylated SFRP2 and SFRP5 showing a tendency towards greater abundance in patients. These data suggested that SFRP genes have tumour-suppresive activity in MPM and that methylated DNA from SFRP gene promoters has the potential to serve as a biomarker for MPM patient plasma.

  11. Cancer-associated splicing variant of tumor suppressor AIMP2/p38: pathological implication in tumorigenesis.

    Directory of Open Access Journals (Sweden)

    Jin Woo Choi

    2011-03-01

    Full Text Available Although ARS-interacting multifunctional protein 2 (AIMP2, also named as MSC p38 was first found as a component for a macromolecular tRNA synthetase complex, it was recently discovered to dissociate from the complex and work as a potent tumor suppressor. Upon DNA damage, AIMP2 promotes apoptosis through the protective interaction with p53. However, it was not demonstrated whether AIMP2 was indeed pathologically linked to human cancer. In this work, we found that a splicing variant of AIMP2 lacking exon 2 (AIMP2-DX2 is highly expressed by alternative splicing in human lung cancer cells and patient's tissues. AIMP2-DX2 compromised pro-apoptotic activity of normal AIMP2 through the competitive binding to p53. The cells with higher level of AIMP2-DX2 showed higher propensity to form anchorage-independent colonies and increased resistance to cell death. Mice constitutively expressing this variant showed increased susceptibility to carcinogen-induced lung tumorigenesis. The expression ratio of AIMP2-DX2 to normal AIMP2 was increased according to lung cancer stage and showed a positive correlation with the survival of patients. Thus, this work identified an oncogenic splicing variant of a tumor suppressor, AIMP2/p38, and suggests its potential for anti-cancer target.

  12. Tumor Suppressor RARRES1 Regulates DLG2, PP2A, VCP, EB1, and Ankrd26

    Directory of Open Access Journals (Sweden)

    Ziad J. Sahab, Michael D. Hall, Lihua Zhang, Amrita K. Cheema, Stephen W. Byers

    2010-01-01

    Full Text Available Retinoic Acid Receptor Responder (RARRES1 initially identified as a novel retinoic acid receptor regulated gene in the skin is a putative tumor suppressor of unknown function. RARRES1 was knocked down in immortalized human prostatic epithelial cell line PWR-1E cells and differential protein expression was identified using differential in-gel electrophoresis (DIGE followed by matrix-assisted laser desorption ionization (MALDI mass spectrometry and western Blot analysis excluding highly abundant proteins routinely identified in almost all proteomics projects. Knock-down of RARRES1: 1- down-regulates PP2A, an enzyme involved in the negative regulation of the growth hormone-stimulated signal transduction pathways; 2- down-regulates Valosin-containing protein causing impaired autophagy; 3- up-regulates the tumor suppressor disks large 2; 4- up-regulates Ankrd26 that belongs to the POTE family of genes that are highly expressed in cancer patients with poor outcome; and 5- down-regulates EB1, a protein that is involved in spindle dynamics and chromosome alignment during mitosis.

  13. Mast cells down-regulate CD4+CD25+ T regulatory cell suppressor function via histamine H1 receptor interaction.

    Science.gov (United States)

    Forward, Nicholas A; Furlong, Suzanne J; Yang, Yongjun; Lin, Tong-Jun; Hoskin, David W

    2009-09-01

    Mast cells promote both innate and acquired immune responses, but little is known about the effect of mast cells on T regulatory (T(reg)) cell function. In this study, we show for the first time that the capacity of murine CD4(+)CD25(+) T(reg) cells to suppress in vitro proliferation by CD4(+)CD25(-) T responder (T(resp)) cells in response to anti-CD3/anti-CD28 mAb-coated beads was reduced in the presence of syngeneic bone marrow-derived mast cells (BMMC) activated by FcepsilonR cross-linking. Activated BMMC culture supernatants or exogenous histamine also inhibited T(reg) cell suppressor function while the histamine H1 receptor-specific antagonist loratadine, but not the H2 receptor-specific antagonist famotidine, restored T(reg) cell suppressor function in the presence of activated BMMC or activated BMMC culture supernatants. Moreover, treatment of T(reg) cells with loratadine, but not famotidine, rescued T(reg) cell suppressor function in the presence of exogenous histamine. In addition, the H1 receptor-specific agonist 2-pyridylethylamine dihydrochloride inhibited T(reg) cell suppressor function to an extent that was comparable to histamine, whereas the H2 receptor-specific agonist amthamine dihydrobromide was without effect. Both T(reg) cells and T(resp) cells expressed H1 receptors. Exposure to histamine caused T(reg) cells to express lower levels of CD25 and the T(reg) cell-specific transcription factor Foxp3. Taken together, these data indicate that BMMC-elaborated histamine inhibited T(reg) cell suppressor function by signaling through the H1 receptor. We suggest that histamine released as a result of mast cell activation by microbial products might cause a transient decrease in T(reg) cell suppressor function, thereby enhancing the development of protective immunity.

  14. Skeletal muscle-specific HMG-CoA reductase knockout mice exhibit rhabdomyolysis: A model for statin-induced myopathy.

    Science.gov (United States)

    Osaki, Yoshinori; Nakagawa, Yoshimi; Miyahara, Shoko; Iwasaki, Hitoshi; Ishii, Akiko; Matsuzaka, Takashi; Kobayashi, Kazuto; Yatoh, Shigeru; Takahashi, Akimitsu; Yahagi, Naoya; Suzuki, Hiroaki; Sone, Hirohito; Ohashi, Ken; Ishibashi, Shun; Yamada, Nobuhiro; Shimano, Hitoshi

    2015-10-23

    HMG-CoA reductase (HMGCR) catalyzes the conversion of HMG-CoA to mevalonic acid (MVA); this is the rate-limiting enzyme of the mevalonate pathway that synthesizes cholesterol. Statins, HMGCR inhibitors, are widely used as cholesterol-reducing drugs. However, statin-induced myopathy is the most adverse side effect of statins. To eludicate the mechanisms underlying statin the myotoxicity and HMGCR function in the skeletal muscle, we developed the skeletal muscle-specific HMGCR knockout mice. Knockout mice exhibited postnatal myopathy with elevated serum creatine kinase levels and necrosis. Myopathy in knockout mice was completely rescued by the oral administration of MVA. These results suggest that skeletal muscle toxicity caused by statins is dependent on the deficiencies of HMGCR enzyme activity and downstream metabolites of the mevalonate pathway in skeletal muscles rather than the liver or other organs. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. ARGINASE ENZYMES IN ISOLATED AIRWAYS FROM NORMAL AND NITRIC OXIDE SYNTHASE 2-KNOCKOUT MICE EXPOSED TO OVALBUMIN

    Science.gov (United States)

    Bratt, Jennifer M.; Franzi, Lisa M.; Linderholm, Angela L.; Last, Michael S.; Kenyon, Nicholas J.; Last, Jerold A.

    2009-01-01

    Arginase has been suggested to compete with nitric oxide synthase (NOS) for their common substrate, L-arginine. To study the mechanisms underlying this interaction, we compared arginase expression in isolated airways and the consequences of inhibiting arginase activity in vivo with NO production, lung inflammation, and lung function in both C57BL/6 and NOS2 knockout mice undergoing ovalbumin-induced airway inflammation, a mouse model of asthma. Arginases I and II were measured by western blot in isolated airways from sensitized C57BL/6 mice exposed to ovalbumin aerosol. Physiological and biochemical responses---inflammation, lung compliance, airway hyperreactivity, exhaled NO concentration, arginine concentration--were compared with the responses of NOS2 knockout mice. NOS2 knockout mice had increased total cells in lung lavage, decreased lung compliance, and increased airway hyperreactivity. Both arginase I and arginase II were constitutively expressed in the airways of normal C57BL/6 mice. Arginase I was up-regulated approximately 8-fold in the airways of C57BL/6 mice exposed to ovalbumin. Expression of both arginase isoforms were significantly upregulated in NOS2 knockout mice exposed to ovalbumin, with about 40- and 4-fold increases in arginases I and II, respectively. Arginine concentration in isolated airways was not significantly different in any of the groups studied. Inhibition of arginase by systemic treatment of C57BL/6 mice with a competitive inhibitor, Nω-hydroxy-nor-L-arginine (nor-NOHA), significantly decreased the lung inflammatory response to ovalbumin in these animals. We conclude that NOS2 knockout mice are more sensitive to ovalbumin-induced airway inflammation and its sequelae than are C57BL/6 mice, as determined by increased total cells in lung lavage, decreased lung compliance, and increased airway hyperreactivity, and that these findings are strongly correlated with increased expression of both arginase isoforms in the airways of the NOS2

  16. Identification of differentially expressed proteins in spontaneous thymic lymphomas from knockout mice with deletion of p53

    DEFF Research Database (Denmark)

    Honoré, Bent; Buus, Søren; Claësson, Mogens H

    2008-01-01

    ABSTRACT: BACKGROUND: Knockout mice with a deletion of p53 spontaneously develop thymic lymphomas. Two cell lines (SM5 and SM7), established from two independent tumours, exhibited about fifty to seventy two-fold differentially expressed proteins compared to wild type thymocytes by two-dimensiona......ABSTRACT: BACKGROUND: Knockout mice with a deletion of p53 spontaneously develop thymic lymphomas. Two cell lines (SM5 and SM7), established from two independent tumours, exhibited about fifty to seventy two-fold differentially expressed proteins compared to wild type thymocytes by two...

  17. Isolation and characterization of coronary endothelial and smooth muscle cells from A1 adenosine receptor-knockout mice

    OpenAIRE

    Teng, Bunyen; Ansari, Habib R.; Oldenburg, Peter J.; Schnermann, J.; Mustafa, S. Jamal

    2005-01-01

    Mice have been used widely in in vivo and in vitro cardiovascular research. The availability of knockout mice provides further clues to the physiological significance of specific receptor subtypes. Adenosine A1 receptor (A1AR)-knockout (A1KO) mice and their wild-type (A1WT) controls were employed in this investigation. The heart and aortic arch were carefully removed and retroinfused with enzyme solution (1 mg/ml collagenase type I, 0.5 mg/ml soybean trypsin inhibitor, 3% BSA, and 2% antibiot...

  18. Effect of Cyp27A1 gene dosage on atherosclerosis development in ApoE-knockout mice.

    OpenAIRE

    Zurkinden L Solcà C Vögeli IA Vogt B Ackermann D Erickson SK Frey FJ Sviridov D Escher G.

    2014-01-01

    In humans, sterol 27-hydroxylase (CYP27A1) deficiency leads to cholesterol deposition in tendons and vasculature. Thus, in addition to its role in bile acid synthesis, where it converts cholesterol to 27-hydroxycholesterol (27-OHC), CYP27A1 may also be atheroprotective. Cyp27A1-deficient (Cyp27A1−/−) mice were crossed with apolipoprotein E (apoE)-deficient mice. Cyp27A1+/+/apoE−/− [ApoE-knockout (KO)], Cyp27A1+/−/apoE−/− heterozygous (het), and Cyp27A1−/−/apoE−/− [double-knockout (DKO)] mice ...

  19. Comparative effects of chlorpyrifos in wild type and cannabinoid Cb1 receptor knockout mice

    Energy Technology Data Exchange (ETDEWEB)

    Baireddy, Praveena; Liu, Jing; Hinsdale, Myron; Pope, Carey, E-mail: carey.pope@okstate.edu

    2011-11-15

    Endocannabinoids (eCBs) modulate neurotransmission by inhibiting the release of a variety of neurotransmitters. The cannabinoid receptor agonist WIN 55.212-2 (WIN) can modulate organophosphorus (OP) anticholinesterase toxicity in rats, presumably by inhibiting acetylcholine (ACh) release. Some OP anticholinesterases also inhibit eCB-degrading enzymes. We studied the effects of the OP insecticide chlorpyrifos (CPF) on cholinergic signs of toxicity, cholinesterase activity and ACh release in tissues from wild type (+/+) and cannabinoid CB1 receptor knockout (-/-) mice. Mice of both genotypes (n = 5-6/treatment group) were challenged with CPF (300 mg/kg, 2 ml/kg in peanut oil, sc) and evaluated for functional and neurochemical changes. Both genotypes exhibited similar cholinergic signs and cholinesterase inhibition (82-95% at 48 h after dosing) in cortex, cerebellum and heart. WIN reduced depolarization-induced ACh release in vitro in hippocampal slices from wild type mice, but had no effect in hippocampal slices from knockouts or in striatal slices from either genotype. Chlorpyrifos oxon (CPO, 100 {mu}M) reduced release in hippocampal slices from both genotypes in vitro, but with a greater reduction in tissues from wild types (21% vs 12%). CPO had no significant in vitro effect on ACh release in striatum. CPF reduced ACh release in hippocampus from both genotypes ex vivo, but reduction was again significantly greater in tissues from wild types (52% vs 36%). In striatum, CPF led to a similar reduction (20-23%) in tissues from both genotypes. Thus, while CB1 deletion in mice had little influence on the expression of acute toxicity following CPF, CPF- or CPO-induced changes in ACh release appeared sensitive to modulation by CB1-mediated eCB signaling in a brain-regional manner. -- Highlights: Black-Right-Pointing-Pointer C57Bl/6 mice showed dose-related cholinergic toxicity following subcutaneous chlorpyrifos exposure. Black-Right-Pointing-Pointer Wild type and

  20. RNA-seq reveals transcriptome changes in goats following myostatin gene knockout

    Science.gov (United States)

    Cai, Bei; Zhou, Shiwei; Zhu, Haijing; Qu, Lei; Wang, Xiaolong

    2017-01-01

    Myostatin (MSTN) is a powerful negative regulator of skeletal muscle mass in mammalian species that is primarily expressed in skeletal muscles, and mutations of its encoding gene can result in the double-muscling trait. In this study, the CRISPR/Cas9 technique was used to edit MSTN in Shaanbei Cashmere goats and generate knockout animals. RNA sequencing was used to determine and compare the transcriptome profiles of the muscles from three wild-type (WT) goats, three fibroblast growth factor 5 (FGF5) knockout goats (FGF5+/- group) and three goats with disrupted expression of both the FGF5 and MSTN genes (FM+/- group). The sequence reads were obtained using the Illumina HiSeq 2000 system and mapped to the Capra hircus reference genome using TopHat (v2.0.9). In total, 68.93, 62.04 and 66.26 million clean sequencing reads were obtained from the WT, FM+/- and FGF5+/- groups, respectively. There were 201 differentially expressed genes (DEGs) between the WT and FGF5+/- groups, with 86 down- and 115 up-regulated genes in the FGF5+/- group. Between the WT and FM+/- groups, 121 DEGs were identified, including 81 down- and 40 up-regulated genes in the FM+/- group. A total of 198 DEGs were detected between the FGF5+/- group and FM+/- group, with 128 down- and 70 up-regulated genes in the FM+/- group. At the transcriptome level, we found substantial changes in genes involved in fatty acid metabolism and the biosynthesis of unsaturated fatty acids, such as stearoyl-CoA dehydrogenase, 3-hydroxyacyl-CoA dehydratase 2, ELOVL fatty acid elongase 6 and fatty acid synthase, suggesting that the expression levels of these genes may be directly regulated by MSTN and that these genes are likely downstream targets of MSTN with potential roles in lipid metabolism in goats. Moreover, five randomly selected DEGs were further validated with qRT-PCR, and the results were consistent with the transcriptome analysis. The present study provides insight into the unique transcriptome profile of the

  1. RNA-seq reveals transcriptome changes in goats following myostatin gene knockout.

    Directory of Open Access Journals (Sweden)

    Lamei Wang

    Full Text Available Myostatin (MSTN is a powerful negative regulator of skeletal muscle mass in mammalian species that is primarily expressed in skeletal muscles, and mutations of its encoding gene can result in the double-muscling trait. In this study, the CRISPR/Cas9 technique was used to edit MSTN in Shaanbei Cashmere goats and generate knockout animals. RNA sequencing was used to determine and compare the transcriptome profiles of the muscles from three wild-type (WT goats, three fibroblast growth factor 5 (FGF5 knockout goats (FGF5+/- group and three goats with disrupted expression of both the FGF5 and MSTN genes (FM+/- group. The sequence reads were obtained using the Illumina HiSeq 2000 system and mapped to the Capra hircus reference genome using TopHat (v2.0.9. In total, 68.93, 62.04 and 66.26 million clean sequencing reads were obtained from the WT, FM+/- and FGF5+/- groups, respectively. There were 201 differentially expressed genes (DEGs between the WT and FGF5+/- groups, with 86 down- and 115 up-regulated genes in the FGF5+/- group. Between the WT and FM+/- groups, 121 DEGs were identified, including 81 down- and 40 up-regulated genes in the FM+/- group. A total of 198 DEGs were detected between the FGF5+/- group and FM+/- group, with 128 down- and 70 up-regulated genes in the FM+/- group. At the transcriptome level, we found substantial changes in genes involved in fatty acid metabolism and the biosynthesis of unsaturated fatty acids, such as stearoyl-CoA dehydrogenase, 3-hydroxyacyl-CoA dehydratase 2, ELOVL fatty acid elongase 6 and fatty acid synthase, suggesting that the expression levels of these genes may be directly regulated by MSTN and that these genes are likely downstream targets of MSTN with potential roles in lipid metabolism in goats. Moreover, five randomly selected DEGs were further validated with qRT-PCR, and the results were consistent with the transcriptome analysis. The present study provides insight into the unique transcriptome

  2. Tat RNA silencing suppressor activity contributes to perturbation of lymphocyte miRNA by HIV-1

    Directory of Open Access Journals (Sweden)

    Yu Lianbo

    2011-05-01

    Full Text Available Abstract Background MicroRNA (miRNA-mediated RNA silencing is integral to virtually every cellular process including cell cycle progression and response to virus infection. The interplay between RNA silencing and HIV-1 is multifaceted, and accumulating evidence posits a strike-counterstrike interface that alters the cellular environment to favor virus replication. For instance, miRNA-mediated RNA silencing of HIV-1 translation is antagonized by HIV-1 Tat RNA silencing suppressor activity. The activity of HIV-1 accessory proteins Vpr/Vif delays cell cycle progression, which is a process prominently modulated by miRNA. The expression profile of cellular miRNA is altered by HIV-1 infection in both cultured cells and clinical samples. The open question stands of what, if any, is the contribution of Tat RNA silencing suppressor activity or Vpr/Vif activity to the perturbation of cellular miRNA by HIV-1. Results Herein, we compared the perturbation of miRNA expression profiles of lymphocytes infected with HIV-1NL4-3 or derivative strains that are deficient in Tat RNA silencing suppressor activity (Tat K51A substitution or ablated of the vpr/vif open reading frames. Microarrays recapitulated the perturbation of the cellular miRNA profile by HIV-1 infection. The miRNA expression trends overlapped ~50% with published microarray results on clinical samples from HIV-1 infected patients. Moreover, the number of miRNA perturbed by HIV-1 was largely similar despite ablation of Tat RSS activity and Vpr/Vif; however, the Tat RSS mutation lessened HIV-1 downregulation of twenty-two miRNAs. Conclusions Our study identified miRNA expression changes attributable to Tat RSS activity in HIV-1NL4-3. The results accomplish a necessary step in the process to understand the interface of HIV-1 with host RNA silencing activity. The overlap in miRNA expression trends observed between HIV-1 infected CEMx174 lymphocytes and primary cells supports the utility of cultured

  3. Increased cocaine self-administration in M4 muscarinic acetylcholine receptor knockout mice

    DEFF Research Database (Denmark)

    Schmidt, Lene Sørensen; Thomsen, Morgane; Weikop, Pia

    2011-01-01

    Rationale The reinforcing effects of cocaine are mediated by the mesolimbic dopamine system. Behavioral and neurochemical studies have shown that the cholinergic muscarinic M4 receptor subtype plays an important role in regulation of dopaminergic neurotransmission. Objectives Here we investigated...... for the first time the involvement of M4 receptors in the reinforcing effects of cocaine using chronic intravenous cocaine self-administration in extensively backcrossed M4 receptor knockout (M4 -/-) mice. Methods We evaluated acquisition of cocaine self-administration in experimentally naïve mice. Both cocaine...... self-administration and food-maintained operant behavior were evaluated under fixed ratio 1 (FR 1) and progressive ratio (PR) schedules of reinforcement. In addition, cocaine-induced dopamine release and cocaine-induced hyperactivity were evaluated. Results M4 -/- mice earned significantly more cocaine...

  4. Management Of Hanford KW Basin Knockout Pot Sludge As Spent Nuclear Fuel

    Energy Technology Data Exchange (ETDEWEB)

    Raymond, R. E. [CH2M HIll Plateau Remediation Company, Richland, WA (United States); Evans, K. M. [AREVA, Avignon (France)

    2012-10-22

    CH2M HILL Plateau Remediation Company (CHPRC) and AREVA Federal Services, LLC (AFS) have been working collaboratively to develop and deploy technologies to remove, transport, and interim store remote-handled sludge from the 10S-K West Reactor Fuel Storage Basin on the U.S. Department of Energy (DOE) Hanford Site near Richland, WA, USA. Two disposal paths exist for the different types of sludge found in the K West (KW) Basin. One path is to be managed as Spent Nuclear Fuel (SNF) with eventual disposal at an SNF at a yet to be licensed repository. The second path will be disposed as remote-handled transuranic (RH-TRU) waste at the Waste Isolation Pilot Plant (WIPP) in Carlsbad, NM. This paper describes the systems developed and executed by the Knockout Pot (KOP) Disposition Subproject for processing and interim storage of the sludge managed as SNF, (i.e., KOP material).

  5. The effect of insulin deficiency on tau and neurofilament in the insulin knockout mouse

    International Nuclear Information System (INIS)

    Schechter, Ruben; Beju, Delia; Miller, Kenneth E.

    2005-01-01

    Complications of diabetes mellitus within the nervous system are peripheral and central neuropathy. In peripheral neuropathy, defects in neurofilament and microtubules have been demonstrated. In this study, we examined the effects of insulin deficiency within the brain in insulin knockout mice (I(-/-)). The I(-/-) exhibited hyperphosphorylation of tau, at threonine 231, and neurofilament. In addition, we showed hyperphosphorylation of c-Jun N-terminal kinase (JNK) and glycogen synthase kinase 3 β (GSK-3 β) at serine 9. Extracellular signal-regulated kinase 1 (ERK 1) showed decrease in phosphorylation, whereas ERK 2 showed no changes. Ultrastructural examination demonstrated swollen mitochondria, endoplasmic reticulum, and Golgi apparatus, and dispersion of the nuclear chromatin. Microtubules showed decrease in the number of intermicrotubule bridges and neurofilament presented as bunches. Thus, lack of insulin brain stimulation induces JNK hyperphosphorylation followed by hyperphosphorylation of tau and neurofilament, and ultrastructural cellular damage, that over time may induce decrease in cognition and learning disabilities

  6. Protein knockouts in living eukaryotes using deGradFP and green fluorescent protein fusion targets.

    Science.gov (United States)

    Caussinus, Emmanuel; Kanca, Oguz; Affolter, Markus

    2013-09-24

    This unit describes deGradFP (degrade Green Fluorescent Protein), an easy-to-implement protein knockout method applicable in any eukaryotic genetic system. Depleting a protein in order to study its function in a living organism is usually achieved at the gene level (genetic mutations) or at the RNA level (RNA interference and morpholinos). However, any system that acts upstream of the proteic level depends on the turnover rate of the existing target protein, which can be extremely slow. In contrast, deGradFP is a fast method that directly depletes GFP fusion proteins. In particular, deGradFP is able to counteract maternal effects in embryos and causes early and fast onset loss-of-function phenotypes of maternally contributed proteins. Copyright © 2013 John Wiley & Sons, Inc.

  7. Management Of Hanford KW Basin Knockout Pot Sludge As Spent Nuclear Fuel

    International Nuclear Information System (INIS)

    Raymond, R. E.; Evans, K. M.

    2012-01-01

    CH2M Hill Plateau Remediation Company (CHPRC) and AREVA Federal Services, LLC (AFS) have been working collaboratively to develop and deploy technologies to remove, transport, and interim store remote-handled sludge from the 10S-K West Reactor Fuel Storage Basin on the U.S. Department of Energy (DOE) Hanford Site near Richland, WA, USA. Two disposal paths exist for the different types of sludge found in the K West (KW) Basin. One path is to be managed as Spent Nuclear Fuel (SNF) with eventual disposal at an SNF at a yet to be licensed repository. The second path will be disposed as remote-handled transuranic (RH-TRU) waste at the Waste Isolation Pilot Plant (WIPP) in Carlsbad, NM. This paper describes the systems developed and executed by the Knockout Pot (KOP) Disposition Subproject for processing and interim storage of the sludge managed as SNF, (i.e., KOP material)

  8. Zika virus infection of adult and fetal STAT2 knock-out hamsters.

    Science.gov (United States)

    Siddharthan, Venkatraman; Van Wettere, Arnaud J; Li, Rong; Miao, Jinxin; Wang, Zhongde; Morrey, John D; Julander, Justin G

    2017-07-01

    Zika virus (ZIKV) infection was investigated in adult and fetal STAT2 knock-out (KO) hamsters. Subcutaneous injection of ZIKV of adults resulted in morbidity, mortality, and infection of the uterus, placenta, brain, spinal cord, and testicles, thus providing an opportunity to evaluate congenital ZIKV infection in a second rodent species besides mice. ZIKV-infected cells with morphologies of Sertoli cells and spermatogonia were observed in the testes, which may have implications for sexual transmission and male sterility. Neonates exposed as fetuses to ZIKV at 8 days post-coitus were not smaller than controls. Nevertheless, infectious virus and ZIKV RNA was detected in some, but not all, placentas and fetal brains of KO hamsters. STAT2 KO hamsters may be useful for addressing sexual transmission, pathogenesis, routes of fetal infection, and neurological disease outcomes, and may also be used in antiviral or vaccine studies to identify intervention strategies. Copyright © 2017. Published by Elsevier Inc.

  9. Increased radiosensitivity and radiation-induced apoptosis in SRC-3 knockout mice

    International Nuclear Information System (INIS)

    Jin Jie; Wang Yu; Xu Yang; Chen Shilei; Wang Junping; Ran Xinze; Su Yongping; Wang Jin

    2014-01-01

    Steroid receptor coactivator-3 (SRC-3), a multifunctional transcriptional coactivator, plays an important role in regulation of cell apoptosis in chemoresistant cancer cells. However, its role in radiation-induced apoptosis in hematopoietic cells is still unclear. In this study, we used SRC-3 knockout (SRC-3 -/- ) mice to assess the role of SRC-3 in radiation-induced hematopoietic injury in vivo. After a range of doses of irradiation, SRC-3 -/- mice exhibited lower counts of peripheral blood cells and bone marrow (BM) mononuclear cells and excessive BM depression, which resulted in a significantly higher mortality compared with wildtype mice. Moreover, BM mononuclear cells obtained from SRC-3 -/- mice showed a remarkable increase in radiation-induced apoptosis. Collectively, our data demonstrate that SRC-3 plays a role in radiation-induced apoptosis of BM hematopoietic cells. Regulation of SRC-3 might influence the radiosensitivity of hematopoietic cells, which highlights a potential therapeutic target for radiation-induced hematopoietic injury. (author)

  10. PTEN gene knock-out effect of radiosensitivity and its mechanism

    International Nuclear Information System (INIS)

    Fu Chunling; Huo Yanying; Hu Yingchun; Li Gang; Wu Dechang; Gou Qiao; Yang Liu; Mi Can

    2008-01-01

    Objective: To analyze the effect of PTEN gene on radiosensitivity and its mechanism. Methods: The reactive oxygen species levels of MEF1 and MEF1/PTEN -/- cell were determined with flow cytometry. The AKT activity pretreated with diphenyleneiodonium chloride or hydrogen peroxide (H 2 O 2 ) was detected by Western blot. Cell cloning efficiency test was used to detect the radiosensitivity. Results: Deletion of PTEN increased the level of basal reactive oxygen species and decreased the radiosensitivity. Pretreatment with diphenyleneiodonium chloride or hydrogen peroxide influenced the AKT activity of control MEF1 cells but not MEF1/Pten -/- cells. Conclusions: Knock-out of PTEN gene could make AKT constitutively active and block H 2 O 2 mediated PI3K/AKT signal transduction pathway, which should be the most reason of radioresistance. (authors)

  11. Estrogens and Spermiogenesis: New Insights from Type 1 Cannabinoid Receptor Knockout Mice

    Directory of Open Access Journals (Sweden)

    Giovanna Cacciola

    2013-01-01

    Full Text Available Spermatogenesis is a complex mechanism which allows the production of male gametes; it consists of mitotic, meiotic, and differentiation phases. Spermiogenesis is the terminal differentiation process during which haploid round spermatids undergo several biochemical and morphological changes, including extensive remodelling of chromatin and nuclear shape. Spermiogenesis is under control of endocrine, paracrine, and autocrine factors, like gonadotropins and testosterone. More recently, emerging pieces of evidence are suggesting that, among these factors, estrogens may have a role. To date, this is a matter of debate and concern because of the agonistic and antagonistic estrogenic effects that environmental chemicals may have on animal and human with damaging outcome on fertility. In this review, we summarize data which fuel this debate, with a particular attention to our recent results, obtained using type 1 cannabinoid receptor knockout male mice as animal model.

  12. Connecting tubule-selective knockout of AQP2 causes a mild urinary concentrating defect

    DEFF Research Database (Denmark)

    Kortenoeven, Marleen; Pedersen, Nis Borbye; Fenton, Robert A.

    2011-01-01

    Aquaporin-2 (AQP2) is the main vasopressin-regulated water channel in the kidney connecting tubule and collecting ducts and is responsible for the regulation of final urine output. Previous studies on transgenic mice have demonstrated a crucial role of AQP2 in water handling in the collecting duct....... After 2 days of acclimatization, body weight, food and water intake and 24 hr urine were measured for 2 days. Animals where then challenged by a 24 hr water restriction, providing around 55% of baseline water intake in gelled food. Confocal laser scanning immunofluorescence microsopy demonstrated......Osm/l), suggesting a mild urinary concentrating defect. There was no difference in bodyweight, food intake or osmolar excretion. The mean drinking volume was higher in the knockout group. However, this difference was not statistically significant. A 24-hr water restriction decreased urine volume in both the wildtype...

  13. Sortilin 1 knockout alters basal adipose glucose metabolism but not diet-induced obesity in mice.

    Science.gov (United States)

    Li, Jibiao; Matye, David J; Wang, Yifeng; Li, Tiangang

    2017-04-01

    Sortilin 1 (Sort1) is a trafficking receptor that has been implicated in the regulation of plasma cholesterol in humans and mice. Here, we use metabolomics and hyperinsulinemic-euglycemic clamp approaches to obtain further understanding of the in vivo effects of Sort1 deletion on diet-induced obesity as well as on adipose lipid and glucose metabolism. Results show that Sort1 knockout (KO) does not affect Western diet-induced obesity nor adipose fatty acid and ceramide concentrations. Under the basal fasting state, chow-fed Sort1 KO mice have decreased adipose glycolytic metabolites, but Sort1 deletion does not affect insulin-stimulated tissue glucose uptake during the insulin clamp. These results suggest that Sort1 loss-of-function in vivo does not affect obesity development, but differentially modulates adipose glucose metabolism under fasting and insulin-stimulated states. © 2017 Federation of European Biochemical Societies.

  14. DNA-free two-gene knockout in Chlamydomonas reinhardtii via CRISPR-Cas9 ribonucleoproteins.

    Science.gov (United States)

    Baek, Kwangryul; Kim, Duk Hyoung; Jeong, Jooyeon; Sim, Sang Jun; Melis, Anastasios; Kim, Jin-Soo; Jin, EonSeon; Bae, Sangsu

    2016-07-28

    Microalgae are versatile organisms capable of converting CO2, H2O, and sunlight into fuel and chemicals for domestic and industrial consumption. Thus, genetic modifications of microalgae for enhancing photosynthetic productivity, and biomass and bio-products generation are crucial for both academic and industrial applications. However, targeted mutagenesis in microalgae with CRISPR-Cas9 is limited. Here we report, a one-step transformation of Chlamydomonas reinhardtii by the DNA-free CRISPR-Cas9 method rather than plasmids that encode Cas9 and guide RNAs. Outcome was the sequential CpFTSY and ZEP two-gene knockout and the generation of a strain constitutively producing zeaxanthin and showing improved photosynthetic productivity.

  15. AVE 0991-angiotensin-(1-7) receptor agonist, inhibits atherogenesis in apoE-knockout mice.

    Science.gov (United States)

    Toton-Zuranska, J; Gajda, M; Pyka-Fosciak, G; Kus, K; Pawlowska, M; Niepsuj, A; Wolkow, P; Olszanecki, R; Jawien, J; Korbut, R

    2010-04-01

    Recent evidence shows that the renin-angiotensin system is a crucial player in atherosclerotic processes. It was also proved that Ang II promotes atherogenesis. Angiotensin-(1-7) [Ang-(1-7)] opposites Ang II action. Therefore, we would like to find out whether Ang-(1-7) receptor agonist: AVE 0991, could ameliorate atherosclerosis progression in an experimental model of atherosclerosis: apolipoprotein E (apoE) - knockout mice. AVE 0991 inhibited atherogenesis, measured both by "en face" method (7.63+/-1.6% vs. 14.6+/-2.1%) and "cross-section" method (47 235+/-7 546 microm(2) vs. 91 416+/-8 357 microm(2)). This is the first report showing the effect of AVE 0991 on atherogenesis in gene-targeted mice.

  16. Analyzing AbrB-Knockout Effects through Genome and Transcriptome Sequencing of Bacillus licheniformis DW2

    Science.gov (United States)

    Shu, Cheng-Cheng; Wang, Dong; Guo, Jing; Song, Jia-Ming; Chen, Shou-Wen; Chen, Ling-Ling; Gao, Jun-Xiang

    2018-01-01

    As an industrial bacterium, Bacillus licheniformis DW2 produces bacitracin which is an important antibiotic for many pathogenic microorganisms. Our previous study showed AbrB-knockout could significantly increase the production of bacitracin. Accordingly, it was meaningful to understand its genome features, expression differences between wild and AbrB-knockout (ΔAbrB) strains, and the regulation of bacitracin biosynthesis. Here, we sequenced, de novo assembled and annotated its genome, and also sequenced the transcriptomes in three growth phases. The genome of DW2 contained a DNA molecule of 4,468,952 bp with 45.93% GC content and 4,717 protein coding genes. The transcriptome reads were mapped to the assembled genome, and obtained 4,102∼4,536 expressed genes from different samples. We investigated transcription changes in B. licheniformis DW2 and showed that ΔAbrB caused hundreds of genes up-regulation and down-regulation in different growth phases. We identified a complete bacitracin synthetase gene cluster, including the location and length of bacABC, bcrABC, and bacT, as well as their arrangement. The gene cluster bcrABC were significantly up-regulated in ΔAbrB strain, which supported the hypothesis in previous study of bcrABC transporting bacitracin out of the cell to avoid self-intoxication, and was consistent with the previous experimental result that ΔAbrB could yield more bacitracin. This study provided a high quality reference genome for B. licheniformis DW2, and the transcriptome data depicted global alterations across two strains and three phases offered an understanding of AbrB regulation and bacitracin biosynthesis through gene expression. PMID:29599755

  17. 12/15-Lipoxygenase Inhibition or Knockout Reduces Warfarin-Associated Hemorrhagic Transformation After Experimental Stroke.

    Science.gov (United States)

    Liu, Yu; Zheng, Yi; Karatas, Hulya; Wang, Xiaoying; Foerch, Christian; Lo, Eng H; van Leyen, Klaus

    2017-02-01

    For stroke prevention, patients with atrial fibrillation typically receive oral anticoagulation. The commonly used anticoagulant warfarin increases the risk of hemorrhagic transformation (HT) when a stroke occurs; tissue-type plasminogen activator treatment is therefore restricted in these patients. This study was designed to test the hypothesis that 12/15-lipoxygenase (12/15-LOX) inhibition would reduce HT in warfarin-treated mice subjected to experimental stroke. Warfarin was dosed orally in drinking water, and international normalized ratio values were determined using a Coaguchek device. C57BL6J mice or 12/15-LOX knockout mice were subjected to transient middle cerebral artery occlusion with 3 hours severe ischemia (model A) or 2 hours ischemia and tissue-type plasminogen activator infusion (model B), with or without the 12/15-LOX inhibitor ML351. Hemoglobin was determined in brain homogenates, and hemorrhage areas on the brain surface and in brain sections were measured. 12/15-LOX expression was detected by immunohistochemistry. Warfarin treatment resulted in reproducible increased international normalized ratio values and significant HT in both models. 12/15-LOX knockout mice suffered less HT after severe ischemia, and ML351 reduced HT in wild-type mice. When normalized to infarct size, ML351 still independently reduced hemorrhage. HT after tissue-type plasminogen activator was similarly reduced by ML351. In addition to its benefits in infarct size reduction, 12/15-LOX inhibition also may independently reduce HT in warfarin-treated mice. ML351 should be further evaluated as stroke treatment in anticoagulated patients suffering a stroke, either alone or in conjunction with tissue-type plasminogen activator. © 2017 American Heart Association, Inc.

  18. Feasibility of a Conditional Knockout System for Chlamydia Based on CRISPR Interference

    Directory of Open Access Journals (Sweden)

    Scot P. Ouellette

    2018-02-01

    Full Text Available Chlamydia is an obligate intracellular bacterium and, as such, has significantly reduced its genome size and content. Although recent advances have allowed for transformation of C. trachomatis with an exogenous plasmid, genetic manipulation of Chlamydia remains challenging. In particular, the ability to create conditional knockouts has not been developed. This is particularly important given the likelihood that most genes within the small genome of Chlamydia may be essential. Here, I describe the feasibility of using CRISPR interference (CRISPRi based on the catalytically inactive Cas9 variant (dCas9 of Staphylococcus aureus to inducibly, and reversibly, repress gene expression in C. trachomatis. CRISPRi has been developed and used successfully in a variety of bacterial organisms including E. coli and Mycobacterium tuberculosis. I first describe the creation of a single plasmid system for CRISPRi in Chlamydia, targeted to a non-essential gene, incA, that expresses a dispensable inclusion membrane protein. Control transformations of C. trachomatis serovar L2 with plasmids encoding only the dCas9, under the control of an inducible promoter, or only the guide RNA (gRNA targeted to the 5' UTR of incA, expressed constitutively, failed to prevent expression of IncA. Importantly, expression of dCas9 alone did not have a deleterious effect on chlamydiae. Transformation of C. trachomatis with a plasmid combining the dCas9 and a gRNA targeting incA and induction of expression of the dCas9 resulted in the reversible inhibition of IncA expression. Consequently, conditional knockout mediated by CRISPRi is feasible in Chlamydia. Potential improvements and experimental concerns in using the system are also discussed.

  19. Knockout of exogenous EGFP gene in porcine somatic cells using zinc-finger nucleases

    International Nuclear Information System (INIS)

    Watanabe, Masahito; Umeyama, Kazuhiro; Matsunari, Hitomi; Takayanagi, Shuko; Haruyama, Erika; Nakano, Kazuaki; Fujiwara, Tsukasa; Ikezawa, Yuka; Nakauchi, Hiromitsu

    2010-01-01

    Research highlights: → EGFP gene integrated in porcine somatic cells could be knocked out using the ZFN-KO system. → ZFNs induced targeted mutations in porcine primary cultured cells. → Complete absence of EGFP fluorescence was confirmed in ZFN-treated cells. -- Abstract: Zinc-finger nucleases (ZFNs) are expected as a powerful tool for generating gene knockouts in laboratory and domestic animals. Currently, it is unclear whether this technology can be utilized for knocking-out genes in pigs. Here, we investigated whether knockout (KO) events in which ZFNs recognize and cleave a target sequence occur in porcine primary cultured somatic cells that harbor the exogenous enhanced green fluorescent protein (EGFP) gene. ZFN-encoding mRNA designed to target the EGFP gene was introduced by electroporation into the cell. Using the Surveyor nuclease assay and flow cytometric analysis, we confirmed ZFN-induced cleavage of the target sequence and the disappearance of EGFP fluorescence expression in ZFN-treated cells. In addition, sequence analysis revealed that ZFN-induced mutations such as base substitution, deletion, or insertion were generated in the ZFN cleavage site of EGFP-expression negative cells that were cloned from ZFN-treated cells, thereby showing it was possible to disrupt (i.e., knock out) the function of the EGFP gene in porcine somatic cells. To our knowledge, this study provides the first evidence that the ZFN-KO system can be applied to pigs. These findings may open a new avenue to the creation of gene KO pigs using ZFN-treated cells and somatic cell nuclear transfer.

  20. Ascorbic acid reverses the prolonged anesthetic action of pentobarbital in Akr1a-knockout mice.

    Science.gov (United States)

    Ito, Junitsu; Otsuki, Noriyuki; Zhang, Xuhong; Konno, Tasuku; Kurahashi, Toshihiro; Takahashi, Motoko; Yamato, Mayumi; Matsuoka, Yuta; Yamada, Ken-ichi; Miyata, Satoshi; Fujii, Junichi

    2014-01-24

    Aldehyde reductase (AKR1A), a member of the aldo-keto reductase superfamily, is highly expressed in the liver and is involved in both the detoxification of carbonyl compounds and ascorbic acid biosynthesis. By comparison with wild-type mice, Akr1a-knockout (Akr1a(-/-)) mice and human Akrla-transgenic (Akr1a(tg/+)) mice experience different anesthetic actions from pentobarbital-prolonged in Akr1a-knockout (Akr1a(-/-)) mice and shortened in human Akrla-transgenic (Akr1a(tg/+)) mice. We investigated this alteration in the anesthetic efficacy of pentobarbital in Akr1a genetically modified mice. Neither the cytosolic protein of wild-type mouse liver nor purified rat AKR1A directly reduced pentobarbital. Ascorbic acid administration neutralized the prolonged duration of the loss of the righting reflex (LORR) in Akr1a(-/-) mice, but preincubation of pentobarbital with ascorbic acid prior to administration did not change the anesthetic effect. Those results indicated that ascorbic acid does not directly reduce pentobarbital. Enzymatic activities and levels of the proteins of some cytochrome P450s that make up a potent detoxification system for pentobarbital showed no changes in the genetically modified mice examined. Thus, ascorbic acid also had no effect on the detoxification system in the liver. The prolonged duration of LORR in the Akr1a(-/-) mice caused by pentobarbital and the neutralization of the anesthetic effect by ascorbic acid together with other results imply that ascorbic acid alters the responses of the neuronal system to anesthetics. Pentobarbital action is increased under conditions of ascorbic acid deficiency, and this may have to be taken into account when anesthetizing malnourished patients. Copyright © 2013. Published by Elsevier Inc.

  1. The Role of Myeloid-Derived Suppressor Cells in the Immunotherapy of HER2/neu-Positive Breast Carcinomas

    Science.gov (United States)

    2009-10-01

    applications beyond cancer immunotherapy, since increased MDSC have also been seen in some para- sitic infections such as Trypanosoma cruzi [17] and in cases...during acute Trypanosoma cruzi infection: involvement of Ly6G (Gr1(+))CD11b(+)immature myeloid suppressor cells. Int Immu- nol 14(10):1125–1134 18. Guy

  2. DLC1 tumor suppressor gene inhibits migration and invasion of multiple myeloma cells through RhoA GTPase pathway

    Czech Academy of Sciences Publication Activity Database

    Ullmannová-Benson, Veronika; Guan, M.; Zhou, X. G.; Tripathi, V.; Yang, V.; Zimonjic, D. B.; Popescu, C.

    2009-01-01

    Roč. 23, č. 2 (2009), s. 383-390 ISSN 0887-6924 Institutional research plan: CEZ:AV0Z50200510 Keywords : multiple myeloma * tumor suppressor gene * promoter methylation Subject RIV: EC - Immunology Impact factor: 8.296, year: 2009

  3. Catalytic activity of matrix metalloproteinase-19 is essential for tumor suppressor and anti-angiogenic activities in nasopharyngeal carcinoma

    Czech Academy of Sciences Publication Activity Database

    Chan, K.C.; Ko, J.M.; Lung, H.L.; Sedláček, Radislav; Zhang, Z.F.; Luo, D.Z.; Feng, Z.B.; Chen, S.; Chen, H.; Chan, K.W.; Tsao, S.W.; Chua, D.T.; Zabarovsky, E.R.; Stanbridge, E.J.; Lung, M.L.

    2011-01-01

    Roč. 129, č. 8 (2011), s. 1826-1837 ISSN 0020-7136 Grant - others:Research Grants Council of the Hong Kong Special Administrative Region(CN) HKU661708M Institutional research plan: CEZ:AV0Z50520514 Keywords : MMP19 * nasopharyngeal carcinoma * tumor suppressor gene * angiogenesis Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 5.444, year: 2011

  4. Allelic loss of the short arm of chromosome 4 in neuroblastoma suggests a novel tumour suppressor gene locus

    NARCIS (Netherlands)

    Caron, H.; van Sluis, P.; Buschman, R.; Pereira do Tanque, R.; Maes, P.; Beks, L.; de Kraker, J.; Voûte, P. A.; Vergnaud, G.; Westerveld, A.; Slater, R.; Versteeg, R.

    1996-01-01

    Neuroblastoma is a childhood neural crest tumour, genetically characterized by frequent deletions of the short arm of chromosome 1 and amplification of N-myc. Here we report the first evidence for a neuroblastoma tumour suppressor locus on 4pter. Cytogenetically we demonstrated rearrangements of 4p

  5. Mutation analysis of suppressor of cytokine signalling 3, a candidate gene in Type 1 diabetes and insulin sensitivity

    DEFF Research Database (Denmark)

    Gylvin, T; Nolsøe, R; Hansen, T

    2004-01-01

    Beta cell loss in Type 1 and Type 2 diabetes mellitus may result from apoptosis and necrosis induced by inflammatory mediators. The suppressor of cytokine signalling (SOCS)-3 is a natural inhibitor of cytokine signalling and also influences insulin signalling. SOCS3 could therefore be a candidate...... gene in the development of Type 1 and Type 2 diabetes mellitus....

  6. LARG at chromosome 11q23 has functional characteristics of a tumor suppressor in human breast cancer

    Energy Technology Data Exchange (ETDEWEB)

    Ong, Danny C.T.; Rudduck, Christina; Chin, Koei; Kuo, Wen-Lin; Lie, Daniel K.H.; Chua, Constance L.M.; Wong, Chow Yin; Hong, Ga Sze; Gray, Joe; Lee, Ann S.G.

    2008-05-06

    Deletion of 11q23-q24 is frequent in a diverse variety of malignancies, including breast and colorectal carcinoma, implicating the presence of a tumor suppressor gene at that chromosomal region. We show here that LARG, from 11q23, has functional characteristics of a tumor suppressor. We examined a 6-Mb region on 11q23 by high-resolution deletion mapping, utilizing both loss of heterozygosity (LOH) analysis and microarray comparative genomic hybridization (CGH). LARG (also called ARHGEF12), identified from the analyzed region, was underexpressed in 34% of primary breast carcinomas and 80% of breast cancer cell lines including the MCF-7 line. Multiplex ligation-dependent probe amplification on 30 primary breast cancers and six breast cancer cell lines showed that LARG had the highest frequency of deletion compared to the BCSC-1 and TSLC1 genes, two known candidate tumor suppressor genes from 11q. In vitro analysis of breast cancer cell lines that underexpress LARG showed that LARG could be reactivated by trichostatin A, a histone deacetylase inhibitor, but not by 5-Aza-2{prime}-deoxycytidine, a demethylating agent. Bisulfite sequencing and quantitative high-throughput analysis of DNA methylation confirmed the lack of CpG island methylation in LARG in breast cancer. Restoration of LARG expression in MCF-7 cells by stable transfection resulted in reduced proliferation and colony formation, suggesting that LARG has functional characteristics of a tumor suppressor gene.

  7. The tumor suppressor PTEN positively regulates macroautophagy by inhibiting the phosphatidylinositol 3-kinase/protein kinase B pathway

    NARCIS (Netherlands)

    Arico, S.; Petiot, A.; Bauvy, C.; Dubbelhuis, P. F.; Meijer, A. J.; Codogno, P.; Ogier-Denis, E.

    2001-01-01

    The tumor suppressor PTEN is a dual protein and phosphoinositide phosphatase that negatively controls the phosphatidylinositol (PI) 3-kinase/protein kinase B (Akt/PKB) signaling pathway. Interleukin-13 via the activation of the class I PI 3-kinase has been shown to inhibit the macroautophagic

  8. Arginase-1 mRNA expression correlates with myeloid-derived suppressor cell levels in peripheral blood of NSCLC patients

    NARCIS (Netherlands)

    Heuvers, Marlies E.; Muskens, Femke; Bezemer, Koen; Lambers, Margaretha; Dingemans, Anne-Marie C.; Groen, Harry J. M.; Smit, Egbert F.; Hoogsteden, Henk C.; Hegmans, Joost P. J. J.; Aerts, Joachim G. J. V.

    Myeloid-derived suppressor cells (MDSC) are a heterogeneous population of immature and progenitor myeloid cells with immunosuppressive activity that are increased in cancer patients. Until now, the characterization of MDSC in humans was very challenging. The aim of this study was to determine the

  9. The von Hippel-Lindau tumor suppressor regulates programmed cell death 5-mediated degradation of Mdm2

    NARCIS (Netherlands)

    Essers, P B; Klasson, T D; Pereboom, T C; Mans, D A; Nicastro, M; Boldt, K; Giles, R H; MacInnes, A W

    2015-01-01

    Functional loss of the von Hippel-Lindau (VHL) tumor suppressor protein (pVHL), which is part of an E3-ubiquitin ligase complex, initiates most inherited and sporadic clear-cell renal cell carcinomas (ccRCC). Genetic inactivation of the TP53 gene in ccRCC is rare, suggesting that an alternate

  10. Amplification of Mdmx (or Mdm4) directly contributes to tumor formation by inhibiting p53 tumor suppressor activity

    DEFF Research Database (Denmark)

    Danovi, Davide; Meulmeester, Erik; Pasini, Diego

    2004-01-01

    Human tumors are believed to harbor a disabled p53 tumor suppressor pathway, either through direct mutation of the p53 gene or through aberrant expression of proteins acting in the p53 pathway, such as p14(ARF) or Mdm2. A role for Mdmx (or Mdm4) as a key negative regulator of p53 function in vivo...

  11. Loss of heterozygosity in Wilms' tumors, studied for six putative tumor suppressor regions, is limited to chromosome 11

    NARCIS (Netherlands)

    Mannens, M.; Devilee, P.; Bliek, J.; Mandjes, I.; de Kraker, J.; Heyting, C.; Slater, R. M.; Westerveld, A.

    1990-01-01

    Studies on the loss of heterozygosity (LOH) in human malignancies have shown that a number of different chromosomal regions associated with putative tumor suppressor genes may be involved in any one given tumor. We have carried out a similar study on Wilms' tumor using a range of DNA markers for a

  12. Viral counterdefense on RNA silencing : analysis of RNA silencing suppressors from arthropod-borne negative strand RNA plant viruses

    NARCIS (Netherlands)

    Schnettler, E.

    2010-01-01

    This thesis describes that RNA silencing suppressor (RSS) proteins encoded by negative-stranded RNA plant viruses are able to interfere with different RNA silencing pathways in a variety of organisms by interacting with double stranded (ds)RNA molecules. These RSS proteins are able to counteract the

  13. Loss of tumour suppressor PTEN expression in renal injury initiates SMAD3- and p53-dependent fibrotic responses

    NARCIS (Netherlands)

    Samarakoon, Rohan; Helo, Sevann; Dobberfuhl, Amy D; Khakoo, Nidah S; Falke, Lucas; Overstreet, Jessica M; Goldschmeding, Roel; Higgins, Paul J

    Deregulation of the tumour suppressor PTEN occurs in lung and skin fibrosis and diabetic and ischaemic renal injury. However, the potential role of PTEN and associated mechanisms in the progression of kidney fibrosis is unknown. Tubular and interstitial PTEN expression was dramatically decreased in

  14. A functional dissection of PTEN N-terminus : Implications in PTEN subcellular targeting and tumor suppressor activity

    NARCIS (Netherlands)

    Gil, Anabel; Rodríguez-Escudero, Isabel; Stumpf, Miriam; Molina, María; Cid, Víctor J.; Pulido, Rafael

    2015-01-01

    Spatial regulation of the tumor suppressor PTEN is exerted through alternative plasma membrane, cytoplasmic, and nuclear subcellular locations. The N-terminal region of PTEN is important for the control of PTEN subcellular localization and function. It contains both an active nuclear localization

  15. Structural basis for c-KIT inhibition by the suppressor of cytokine signaling 6 (SOCS6) ubiquitin ligase

    DEFF Research Database (Denmark)

    Zadjali, Fahad; Pike, Ashley C W; Vesterlund, Mattias

    2011-01-01

    The c-KIT receptor tyrosine kinase mediates the cellular response to stem cell factor (SCF). Whereas c-KIT activity is important for the proliferation of hematopoietic cells, melanocytes and germ cells, uncontrolled c-KIT activity contributes to the growth of diverse human tumors. Suppressor...

  16. PCR-RFLP to Detect Codon 248 Mutation in Exon 7 of "p53" Tumor Suppressor Gene

    Science.gov (United States)

    Ouyang, Liming; Ge, Chongtao; Wu, Haizhen; Li, Suxia; Zhang, Huizhan

    2009-01-01

    Individual genome DNA was extracted fast from oral swab and followed up with PCR specific for codon 248 of "p53" tumor suppressor gene. "Msp"I restriction mapping showed the G-C mutation in codon 248, which closely relates to cancer susceptibility. Students learn the concepts, detection techniques, and research significance of point mutations or…

  17. The LKB1 tumor suppressor differentially affects anchorage independent growth of HPV positive cervical cancer cell lines

    Energy Technology Data Exchange (ETDEWEB)

    Mack, Hildegard I.D.; Munger, Karl, E-mail: kmunger@rics.bwh.harvard.edu

    2013-11-15

    Infection with high-risk human papillomaviruses is causally linked to cervical carcinogenesis. However, most lesions caused by high-risk HPV infections do not progress to cancer. Host cell mutations contribute to malignant progression but the molecular nature of such mutations is unknown. Based on a previous study that reported an association between liver kinase B1 (LKB1) tumor suppressor loss and poor outcome in cervical cancer, we sought to determine the molecular basis for this observation. LKB1-negative cervical and lung cancer cells were reconstituted with wild type or kinase defective LKB1 mutants and we examined the importance of LKB1 catalytic activity in known LKB1-regulated processes including inhibition of cell proliferation and elevated resistance to energy stress. Our studies revealed marked differences in the biological activities of two kinase defective LKB1 mutants in the various cell lines. Thus, our results suggest that LKB1 may be a cell-type specific tumor suppressor. - Highlights: • LKB1 is a tumor suppressor that is linked to Peutz-Jeghers syndrome. • Peutz-Jeghers syndrome patients have a high incidence of cervical cancer. • Cervical cancer is caused by HPV infections. • This study investigates LKB1 tumor suppressor activity in cervical cancer.

  18. Expression of metastasis suppressor BRMS1 in breast cancer cells results in a marked delay in cellular adhesion to matrix

    Science.gov (United States)

    Metastatic dissemination is a multi-step process that depends on cancer cells’ ability to respond to microenvironmental cues by adapting adhesion abilities and undergoing cytoskeletal rearrangement. Breast Cancer Metastasis Suppressor 1 (BRMS1) affects several steps of the metastatic cascade: it dec...

  19. Overexpression of the p53 tumor suppressor gene product in primary lung adenocarcinomas is associated with cigarette smoking

    NARCIS (Netherlands)

    Westra, W. H.; Offerhaus, G. J.; Goodman, S. N.; Slebos, R. J.; Polak, M.; Baas, I. O.; Rodenhuis, S.; Hruban, R. H.

    1993-01-01

    Mutations in the p53 tumor suppressor gene are frequently observed in primary lung adenocarcinomas, suggesting that these mutations are critical events in the malignant transformation of airway cells. These mutations are often associated with stabilization of the p53 gene product, resulting in the

  20. RORα, a Potential Tumor Suppressor and Therapeutic Target of Breast Cancer

    Directory of Open Access Journals (Sweden)

    Jun Du

    2012-11-01

    Full Text Available The function of the nuclear receptor (NR in breast cancer progression has been investigated for decades. The majority of the nuclear receptors have well characterized natural ligands, but a few of them are orphan receptors for which no ligand has been identified. RORα, one member of the retinoid orphan nuclear receptor (ROR subfamily of orphan receptors, regulates various cellular and pathological activities. RORα is commonly down-regulated and/or hypoactivated in breast cancer compared to normal mammary tissue. Expression of RORα suppresses malignant phenotypes in breast cancer cells, in vitro and in vivo. Activity of RORα can be categorized into the canonical and non-canonical nuclear receptor pathways, which in turn regulate various breast cancer cellular function, including cell proliferation, apoptosis and invasion. This information suggests that RORα is a potent tumor suppressor and a potential therapeutic target for breast cancer.

  1. Catalysis by the tumor-suppressor enzymes PTEN and PTEN-L.

    Directory of Open Access Journals (Sweden)

    Sean B Johnston

    Full Text Available Phosphatase and tensin homologue deleted from chromosome ten (PTEN is a lipid phosphatase tumor suppressor that is lost or inactivated in most human tumors. The enzyme catalyzes the hydrolysis of phosphatidylinositol-(3,4,5-trisphosphate (PIP3 to form phosphatidylinositol-(4,5-bisphosphate (PIP2 and inorganic phosphate. Here, we report on the first continuous assay for the catalytic activity of PTEN. Using this assay, we demonstrate that human PTEN is activated by the reaction product PIP2, as well as in solutions of low salt concentration. This activation is abrogated in the K13A variant, which has a disruption in a putative binding site for PIP2. We also demonstrate that PTEN-L, which derives from alternative translation of the PTEN mRNA, is activated constitutively. These findings have implications for catalysis by PTEN in physiological environments and could expedite the development of PTEN-based chemotherapeutic agents.

  2. Suppressor of cytokine signaling (SOCS)5 ameliorates influenza infection via inhibition of EGFR signaling.

    Science.gov (United States)

    Kedzierski, Lukasz; Tate, Michelle D; Hsu, Alan C; Kolesnik, Tatiana B; Linossi, Edmond M; Dagley, Laura; Dong, Zhaoguang; Freeman, Sarah; Infusini, Giuseppe; Starkey, Malcolm R; Bird, Nicola L; Chatfield, Simon M; Babon, Jeffrey J; Huntington, Nicholas; Belz, Gabrielle; Webb, Andrew; Wark, Peter Ab; Nicola, Nicos A; Xu, Jianqing; Kedzierska, Katherine; Hansbro, Philip M; Nicholson, Sandra E

    2017-02-14

    Influenza virus infections have a significant impact on global human health. Individuals with suppressed immunity, or suffering from chronic inflammatory conditions such as COPD, are particularly susceptible to influenza. Here we show that suppressor of cytokine signaling (SOCS) five has a pivotal role in restricting influenza A virus in the airway epithelium, through the regulation of epidermal growth factor receptor (EGFR). Socs5 -deficient mice exhibit heightened disease severity, with increased viral titres and weight loss. Socs5 levels were differentially regulated in response to distinct influenza viruses (H1N1, H3N2, H5N1 and H11N9) and were reduced in primary epithelial cells from COPD patients, again correlating with increased susceptibility to influenza. Importantly, restoration of SOCS5 levels restricted influenza virus infection, suggesting that manipulating SOCS5 expression and/or SOCS5 targets might be a novel therapeutic approach to influenza.

  3. A tumor suppressor role of the Bub3 spindle checkpoint protein after apoptosis inhibition

    Science.gov (United States)

    Moutinho-Santos, Tatiana

    2013-01-01

    Most solid tumors contain aneuploid cells, indicating that the mitotic checkpoint is permissive to the proliferation of chromosomally aberrant cells. However, mutated or altered expression of mitotic checkpoint genes accounts for a minor proportion of human tumors. We describe a Drosophila melanogaster tumorigenesis model derived from knocking down spindle assembly checkpoint (SAC) genes and preventing apoptosis in wing imaginal discs. Bub3-deficient tumors that were also deficient in apoptosis displayed neoplastic growth, chromosomal aneuploidy, and high proliferative potential after transplantation into adult flies. Inducing aneuploidy by knocking down CENP-E and preventing apoptosis does not induce tumorigenesis, indicating that aneuploidy is not sufficient for hyperplasia. In this system, the aneuploidy caused by a deficient SAC is not driving tumorigenesis because preventing Bub3 from binding to the kinetochore does not cause hyperproliferation. Our data suggest that Bub3 has a nonkinetochore-dependent function that is consistent with its role as a tumor suppressor. PMID:23609535

  4. Are suppressors of cytokine signaling proteins recently identified in atherosclerosis possible therapeutic targets?

    Science.gov (United States)

    Tang, Jingjing; Raines, Elaine W

    2005-10-01

    Atherosclerosis is a slowly progressing chronic inflammatory disease characterized by focal arterial lesions that can ultimately occlude the entire blood vessel and lead to sudden death. Lesions associated with cardiovascular events are those enriched in macrophages and other inflammatory cells. Activation of inflammatory cells within lesions induces the release of cytokines which promotes more inflammation and associated tissue damage if cytokine signaling pathways remain unregulated. Thus, pathways capable of suppressing proinflammatory cytokine signaling hold the potential to limit life-threatening cardiovascular events caused by atherogenesis. This review focuses on suppressors of cytokine signaling proteins recently identified in the atherosclerosis-prone ApoE(-/-) mouse and provides perspectives of their potential for intervention in atherosclerotic lesion progression.

  5. The Role and Potential Therapeutic Application of Myeloid-Derived Suppressor Cells in Allo- and Autoimmunity

    Directory of Open Access Journals (Sweden)

    Qi Zhang

    2015-01-01

    Full Text Available Myeloid-derived suppressor cells (MDSCs are a heterogeneous population of cells that consists of myeloid progenitor cells and immature myeloid cells. They have been identified as a cell population that may affect the activation of CD4+ and CD8+ T-cells to regulate the immune response negatively, which makes them attractive targets for the treatment of transplantation and autoimmune diseases. Several studies have suggested the potential suppressive effect of MDSCs on allo- and autoimmune responses. Conversely, MDSCs have also been found at various stages of differentiation, accumulating during pathological situations, not only during tumor development but also in a variety of inflammatory immune responses, bone marrow transplantation, and some autoimmune diseases. These findings appear to be contradictory. In this review, we summarize the roles of MDSCs in different transplantation and autoimmune diseases models as well as the potential to target these cells for therapeutic benefit.

  6. Tumor suppressor gene E-cadherin and its role in normal and malignant cells

    Directory of Open Access Journals (Sweden)

    Pećina-Šlaus Nives

    2003-10-01

    Full Text Available Abstract E-cadherin tumor suppressor genes are particularly active area of research in development and tumorigenesis. The calcium-dependent interactions among E-cadherin molecules are critical for the formation and maintenance of adherent junctions in areas of epithelial cell-cell contact. Loss of E-cadherin-mediated-adhesion characterises the transition from benign lesions to invasive, metastatic cancer. Nevertheless, there is evidence that E-cadherins may also play a role in the wnt signal transduction pathway, together with other key molecules involved in it, such as beta-catenins and adenomatous poliposis coli gene products. The structure and function of E-cadherin, gene and protein, in normal as well as in tumor cells are reviewed in this paper.

  7. CHIP is a novel tumor suppressor in pancreatic cancer and inhibits tumor growth through targeting EGFR

    Science.gov (United States)

    Wang, Tianxiao; Yang, Jingxuan; Xu, Jianwei; Li, Jian; Cao, Zhe; Zhou, Li; You, Lei; Shu, Hong; Lu, Zhaohui; Li, Huihua; Li, Min; Zhang, Taiping; Zhao, Yupei

    2014-01-01

    Carboxyl terminus of heat shock protein 70-interacting protein (CHIP) is an E3 ubiquitin ligase that is involved in protein quality control and mediates several tumor-related proteins in many cancers, but the function of CHIP in pancreatic cancer is not known. Here we show that CHIP interacts and ubiquitinates epidermal growth factor receptor (EGFR) for proteasome-mediated degradation in pancreatic cancer cells, thereby inhibiting the activation of EGFR downstream pathways. CHIP suppressed cell proliferation, anchor-independent growth, invasion and migration, as well as enhanced apoptosis induced by erlotinib in vitro and in vivo. The expression of CHIP was decreased in pancreatic cancer tissues or sera. Low CHIP expression in tumor tissues was correlated with tumor differentiation and shorter overall survival. These observations indicate that CHIP serves as a novel tumor suppressor by down-regulating EGFR pathway in pancreatic cancer cells, decreased expression of CHIP was associated with poor prognosis in pancreatic cancer. PMID:24722501

  8. Viral suppressors of RNA silencing hinder exogenous and endogenous small RNA pathways in Drosophila.

    Directory of Open Access Journals (Sweden)

    Bassam Berry

    2009-06-01

    Full Text Available In plants and insects, RNA interference (RNAi is the main responder against viruses and shapes the basis of antiviral immunity. Viruses counter this defense by expressing viral suppressors of RNAi (VSRs. While VSRs in Drosophila melanogaster were shown to inhibit RNAi through different modes of action, whether they act on other silencing pathways remained unexplored.Here we show that expression of various plant and insect VSRs in transgenic flies does not perturb the Drosophila microRNA (miRNA pathway; but in contrast, inhibits antiviral RNAi and the RNA silencing response triggered by inverted repeat transcripts, and injection of dsRNA or siRNA. Strikingly, these VSRs also suppressed transposon silencing by endogenous siRNAs (endo-siRNAs.Our findings identify VSRs as tools to unravel small RNA pathways in insects and suggest a cosuppression of antiviral RNAi and endo-siRNA silencing by viruses during fly infections.

  9. The transformation suppressor gene Reck is required for postaxial patterning in mouse forelimbs

    Directory of Open Access Journals (Sweden)

    Mako Yamamoto

    2012-03-01

    The membrane-anchored metalloproteinase-regulator RECK has been characterized as a tumor suppressor. Here we report that mice with reduced Reck-expression show limb abnormalities including right-dominant, forelimb-specific defects in postaxial skeletal elements. The forelimb buds of low-Reck mutants have an altered dorsal ectoderm with reduced Wnt7a and Igf2 expression, and hypotrophy in two signaling centers (i.e., ZPA and AER that are essential for limb outgrowth and patterning. Reck is abundantly expressed in the anterior mesenchyme in normal limb buds; mesenchyme-specific Reck inactivation recapitulates the low-Reck phenotype; and some teratogens downregulate Reck in mesenchymal cells. Our findings illustrate a role for Reck in the mesenchymal-epithelial interactions essential for mammalian development.

  10. A viral suppressor protein inhibits host RNA silencing by hooking up with Argonautes

    KAUST Repository

    Jin, Hailing

    2010-05-01

    RNA viruses are particularly vulnerable to RNAi-based defenses in the host, and thus have evolved specific proteins, known as viral suppressors of RNA silencing (VSRs), as a counterdefense. In this issue of Genes & Development, Azevedo and colleagues (pp. 904-915) discovered that P38, the VSR of Turnip crinkle virus, uses its glycine/tryptophane (GW) motifs as an ARGONAUTE (AGO) hook to attract and disarm the host\\'s essential effector of RNA silencing. Several GW motif-containing cellular proteins are known to be important partners of AGOs in RNA silencing effector complexes in yeast, plants, and animals. The GW motif appears to be a versatile and effective tool for regulating the activities of RNA silencing pathways, and the use of GW mimicry to compete for and inhibit host AGOs may be a strategy used by many pathogens to counteract host RNAi-based defenses. © 2010 by Cold Spring Harbor Laboratory Press.

  11. Myeloid-derived suppressor cells mediate immune suppression in spinal cord injury.

    Science.gov (United States)

    Wang, Lei; Yu, Wei-bo; Tao, Lian-yuan; Xu, Qing

    2016-01-15

    Spinal cord injury (SCI) is characterized by the loss of motor and sensory functions in areas below the level of the lesion and numerous accompanying deficits. Previous studies have suggested that myeloid-derived suppressor cell (MDSC)-induced immune depression may play a pivotal role in the course of SCI. However, the concrete mechanism of these changes regarding immune suppression remains unknown. Here, we created an SCI mouse model to gain further evidence regarding the relationship between MDSCs following SCI and T lymphocyte suppression. We showed that in the SCI mouse model, the expanding MDSCs have the capacity to suppress T cell proliferation, and this suppression could be reversed by blocking the arginase. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. Evolution of the HIV-1 nef gene in HLA-B*57 Positive Elite Suppressors

    Directory of Open Access Journals (Sweden)

    Siliciano Robert F

    2010-11-01

    Full Text Available Abstract Elite controllers or suppressors (ES are HIV-1 infected patients who maintain viral loads of gag and nef in HLA-B*57 positive ES. We previously showed evolution in the gag gene of ES which surprisingly was mostly due to synonymous mutations rather than non-synonymous mutation in targeted CTL epitopes. This finding could be the result of structural constraints on Gag, and we therefore examined the less conserved nef gene. We found slow evolution of nef in plasma virus in some ES. This evolution is mostly due to synonymous mutations and occurs at a rate similar to that seen in the gag gene in the same patients. The results provide further evidence of ongoing viral replication in ES and suggest that the nef and gag genes in these patients respond similarly to selective pressure from the host.

  13. Regulation of protein phosphatase 2A (PP2A) tumor suppressor function by PME-1.

    Science.gov (United States)

    Kaur, Amanpreet; Westermarck, Jukka

    2016-12-15

    Protein phosphatase 2A (PP2A) plays a major role in maintaining cellular signaling homeostasis by dephosphorylation of a variety of signaling proteins and acts as a tumor suppressor. Protein phosphatase methylesterase-1 (PME-1) negatively regulates PP2A activity by highly complex mechanisms that are reviewed here. Importantly, recent studies have shown that PME-1 promotes oncogenic MAPK/ERK and AKT pathway activities in various cancer types. In human glioma, high PME-1 expression correlates with tumor progression and kinase inhibitor resistance. We discuss the emerging cancer-associated function of PME-1 and its potential clinical relevance. © 2016 The Author(s); published by Portland Press Limited on behalf of the Biochemical Society.

  14. Genetic suppressors of the Lotus japonicus har1-1 hypernodulation phenotype

    DEFF Research Database (Denmark)

    Murray, Jeremy; Karas, Bogumil; Ross, Loretta

    2006-01-01

    approach of genetic mapping, targeting induced local lesions in genomics, and sequencing, all non-nodulating mutant lines were characterized and shown to represent new alleles of at least nine independent symbiotic loci. The class of mutants with reduced nodulation capacity was of particular interest...... mutant lines carried more subtle symbiotic phenotypes, either forming white ineffective nodules or showing reduced nodulation capacity. When challenged with Glomus intraradices, 18 of the 61 suppressor lines were unable to establish a symbiosis with this arbuscular mycorrhiza fungus. Using a combined...... because some of them may specify novel plant functions that regulate nodule development in L. japonicus. To facilitate mapping of the latter class of mutants, an introgression line, in which the har1-1 allele was introduced into a polymorphic background of L. japonicus ecotype MG20, was constructed...

  15. ZBTB7A acts as a tumor suppressor through the transcriptional repression of glycolysis

    Science.gov (United States)

    Liu, Xue-Song; Haines, Jenna E.; Mehanna, Elie K.; Genet, Matthew D.; Ben-Sahra, Issam; Asara, John M.; Manning, Brendan D.

    2014-01-01

    Elevated glycolysis is a common metabolic trait of cancer, but what drives such metabolic reprogramming remains incompletely clear. We report here a novel transcriptional repressor-mediated negative regulation of glycolysis. ZBTB7A, a member of the POK (POZ/BTB and Krüppel) transcription repressor family, directly binds to the promoter and represses the transcription of critical glycolytic genes, including GLUT3, PFKP, and PKM. Analysis of The Cancer Genome Atlas (TCGA) data sets reveals that the ZBTB7A locus is frequently deleted in many human tumors. Significantly, reduced ZBTB7A expression correlates with up-regulation of the glycolytic genes and poor survival in colon cancer patients. Remarkably, while ZBTB7A-deficient tumors progress exceedingly fast, they exhibit an unusually heightened sensitivity to glycolysis inhibition. Our study uncovers a novel tumor suppressor role of ZBTB7A in directly suppressing glycolysis. PMID:25184678

  16. Dystrophin is a tumor suppressor in human cancers with myogenic programs.

    Science.gov (United States)

    Wang, Yuexiang; Marino-Enriquez, Adrian; Bennett, Richard R; Zhu, Meijun; Shen, Yiping; Eilers, Grant; Lee, Jen-Chieh; Henze, Joern; Fletcher, Benjamin S; Gu, Zhizhan; Fox, Edward A; Antonescu, Cristina R; Fletcher, Christopher D M; Guo, Xiangqian; Raut, Chandrajit P; Demetri, George D; van de Rijn, Matt; Ordog, Tamas; Kunkel, Louis M; Fletcher, Jonathan A

    2014-06-01

    Many common human mesenchymal tumors, including gastrointestinal stromal tumor (GIST), rhabdomyosarcoma (RMS) and leiomyosarcoma (LMS), feature myogenic differentiation. Here we report that intragenic deletion of the dystrophin-encoding and muscular dystrophy-associated DMD gene is a frequent mechanism by which myogenic tumors progress to high-grade, lethal sarcomas. Dystrophin is expressed in the non-neoplastic and benign counterparts of GIST, RMS and LMS tumors, and DMD deletions inactivate larger dystrophin isoforms, including 427-kDa dystrophin, while preserving the expression of an essential 71-kDa isoform. Dystrophin inhibits myogenic sarcoma cell migration, invasion, anchorage independence and invadopodia formation, and dystrophin inactivation was found in 96%, 100% and 62% of metastatic GIST, embryonal RMS and LMS samples, respectively. These findings validate dystrophin as a tumor suppressor and likely anti-metastatic factor, suggesting that therapies in development for muscular dystrophies may also have relevance in the treatment of cancer.

  17. Enhancer-Mediated Oncogenic Function of the Menin Tumor Suppressor in Breast Cancer

    Directory of Open Access Journals (Sweden)

    Koen M.A. Dreijerink

    2017-03-01

    Full Text Available While the multiple endocrine neoplasia type 1 (MEN1 gene functions as a tumor suppressor in a variety of cancer types, we explored its oncogenic role in breast tumorigenesis. The MEN1 gene product menin is involved in H3K4 trimethylation and co-activates transcription. We integrated ChIP-seq and RNA-seq data to identify menin target genes. Our analysis revealed that menin-dependent target gene promoters display looping to distal enhancers that are bound by menin, FOXA1 and GATA3. In this fashion, MEN1 co-regulates a proliferative breast cancer-specific gene expression program in ER+ cells. In primary mammary cells, MEN1 exerts an anti-proliferative function by regulating a distinct expression signature. Our findings clarify the cell-type-specific functions of MEN1 and inform the development of menin-directed treatments for breast cancer.

  18. Application of nonlinear magnetic vibro-impact vibration suppressor and energy harvester

    Science.gov (United States)

    Afsharfard, Aref

    2018-01-01

    In the present study, application of a single unit vibro-impact system is improved. For this reason, in the so-called "magnetic impact damper" the impact mass is replaced by a permanent magnet, which moves in coil of gap enclosure. In the magnetic impact damper, wasting energy during inelastic contacts of masses and converting energy into electrical energy during the mass movement inside the coil, leads to suppress undesired vibrations. In this study it is shown that the magnetic impact dampers are not only good vibration suppressors but also they can harvest electrical energy. Effect of changing the main parameters of this system including gap size, load resistance and electromagnetic coupling coefficient is studied on the vibratory and energy behavior of the magnetic impact dampers. Finally using several user oriented charts, it is shown that energy-based and vibration-based design considerations can effectively improve application of the discussed vibro-impact system.

  19. Paracrine Apoptotic Effect of p53 Mediated by Tumor Suppressor Par-4

    Directory of Open Access Journals (Sweden)

    Ravshan Burikhanov

    2014-01-01

    Full Text Available The guardian of the genome, p53, is often mutated in cancer and may contribute to therapeutic resistance. Given that p53 is intact and functional in normal tissues, we harnessed its potential to inhibit the growth of p53-deficient cancer cells. Specific activation of p53 in normal fibroblasts selectively induced apoptosis in p53-deficient cancer cells. This paracrine effect was mediated by p53-dependent secretion of the tumor suppressor Par-4. Accordingly, the activation of p53 in normal mice, but not p53−/− or Par-4−/− mice, caused systemic elevation of Par-4, which induced apoptosis of p53-deficient tumor cells. Mechanistically, p53 induced Par-4 secretion by suppressing the expression of its binding partner, UACA, which sequesters Par-4. Thus, normal cells can be empowered by p53 activation to induce Par-4 secretion for the inhibition of therapy-resistant tumors.

  20. Generation of a heterozygous knockout human embryonic stem cell line for the OCIAD1 locus using CRISPR/CAS9 mediated targeting: BJNhem20-OCIAD1-CRISPR-20

    Directory of Open Access Journals (Sweden)

    Deeti K. Shetty

    2016-03-01

    Full Text Available Ovarian carcinoma immuno-reactive antigen domain containing 1(OCIAD1 single copy was knocked out generating an OCIAD1 heterozygous knockout human embryonic stem line named BJNhem20-OCIAD1-CRISPR-20. The line was generated using CRISPR-Cas9D10A double nickase knockout strategy (Mali et al., 2013.

  1. Methylation of the tumor suppressor protein, BRCA1, influences its transcriptional cofactor function.

    Directory of Open Access Journals (Sweden)

    Irene Guendel

    Full Text Available BACKGROUND: Approximately half of hereditary breast cancers have mutations in either BRCA1 or BRCA2. BRCA1 is a multifaceted tumor suppressor protein that has implications in processes such as cell cycle, transcription, DNA damage response and chromatin remodeling. This multifunctional nature of BRCA1 is achieved by exerting its many effects through modulation of transcription. Many cellular events are dictated by covalent modification of proteins, an important mechanism in regulating protein and genome function; of which protein methylation is an important posttranslational modification with activating or repressive effects. METHODS/PRINCIPAL FINDINGS: Here we demonstrate for the first time that BRCA1 is methylated both in breast cancer cell lines and breast cancer tumor samples at arginine and lysine residues through immunoprecipitation and western blot analysis. Arginine methylation by PRMT1 was observed in vitro and the region of BRCA1 504-802 shown to be highly methylated. PRMT1 was detected in complex with BRCA1 504-802 through in vitro binding assays and co-immunoprecipitated with BRCA1. Inhibition of methylation resulted in decreased BRCA1 methylation and alteration of BRCA1 binding to promoters in vivo as shown through chromatin immunoprecipitation assays. Knockdown of PRMT1 also resulted in increased BRCA1 binding to particular promoters in vivo. Finally, following methylation inhibition, Sp1 was found to preferentially associate with hypo-methylated BRCA1 and STAT1 was found to preferentially associate with hyper-methylated BRCA1. CONCLUSIONS/SIGNIFICANCE: These results suggest that methylation may influence either the ability of BRCA1 to bind to specific promoters or protein-protein interactions which alters the recruitment of BRCA1 to these promoters. Thus, given the importance of BRCA1 to genomic stability, methylation of BRCA1 may ultimately affect the tumor suppressor ability of BRCA1.

  2. Snail transcription factor negatively regulates maspin tumor suppressor in human prostate cancer cells

    Directory of Open Access Journals (Sweden)

    Neal Corey L

    2012-08-01

    Full Text Available Abstract Background Maspin, a putative tumor suppressor that is down-regulated in breast and prostate cancer, has been associated with decreased cell motility. Snail transcription factor is a zinc finger protein that is increased in breast cancer and is associated with increased tumor motility and invasion by induction of epithelial-mesenchymal transition (EMT. We investigated the molecular mechanisms by which Snail increases tumor motility and invasion utilizing prostate cancer cells. Methods Expression levels were analyzed by RT-PCR and western blot analyses. Cell motility and invasion assays were performed, while Snail regulation and binding to maspin promoter was analyzed by luciferase reporter and chromatin immunoprecipitation (ChIP assays. Results Snail protein expression was higher in different prostate cancer cells lines as compared to normal prostate epithelial cells, which correlated inversely with maspin expression. Snail overexpression in 22Rv1 prostate cancer cells inhibited maspin expression and led to increased migration and invasion. Knockdown of Snail in DU145 and C4-2 cancer cells resulted in up-regulation of maspin expression, concomitant with decreased migration. Transfection of Snail into 22Rv1 or LNCaP cells inhibited maspin promoter activity, while stable knockdown of Snail in C4-2 cells increased promoter activity. ChIP analysis showed that Snail is recruited to the maspin promoter in 22Rv1 cells. Conclusions Overall, this is the first report showing that Snail can negatively regulate maspin expression by directly repressing maspin promoter activity, leading to increased cell migration and invasion. Therefore, therapeutic targeting of Snail may be useful to re-induce expression of maspin tumor suppressor and prevent prostate cancer tumor progression.

  3. PTEN functions as a melanoma tumor suppressor by promoting host immune response.

    Science.gov (United States)

    Dong, Y; Richards, J-Ae; Gupta, R; Aung, P P; Emley, A; Kluger, Y; Dogra, S K; Mahalingam, M; Wajapeyee, N

    2014-09-18

    Cancer cells acquire several traits that allow for their survival and progression, including the ability to evade the host immune response. However, the mechanisms by which cancer cells evade host immune responses remain largely elusive. Here we study the phenomena of immune evasion in malignant melanoma cells. We find that the tumor suppressor phosphatase and tensin homolog (PTEN) is an important regulator of the host immune response against melanoma cells. Mechanistically, PTEN represses the expression of immunosuppressive cytokines by blocking the phosphatidylinositide 3-kinase (PI3K) pathway. In melanoma cells lacking PTEN, signal transducer and activator of transcription 3 activates the transcription of immunosuppressive cytokines in a PI3K-dependent manner. Furthermore, conditioned media from PTEN-deficient, patient-derived short-term melanoma cultures and established melanoma cell lines blocked the production of the interleukin-12 (IL-12) in human monocyte-derived dendritic cells. Inhibition of IL-12 production was rescued by restoring PTEN or using neutralizing antibodies against the immunosuppressive cytokines. Furthermore, we report that PTEN, as an alternative mechanism to promote the host immune response against cancer cells, represses the expression of programmed cell death 1 ligand, a known repressor of the host immune response. Finally, to establish the clinical significance of our results, we analyzed malignant melanoma patient samples with or without brisk host responses. These analyses confirmed that PTEN loss is associated with a higher percentage of malignant melanoma samples with non-brisk host responses compared with samples with brisk host responses. Collectively, these results establish that PTEN functions as a melanoma tumor suppressor in part by regulating the host immune response against melanoma cells and highlight the importance of assessing PTEN status before recruiting melanoma patients for immunotherapies.

  4. Acquisition of repertoires of suppressor T cells under the influence of macrophages

    International Nuclear Information System (INIS)

    Soejima, T.; Nagayama, A.; Sado, T.; Taniguchi, M.

    1988-01-01

    Acquisition of repertoires and genetic restriction specificities of suppressor T cells (Ts) and their factors were studied by using full allogeneic radiation bone marrow chimera and H-2 congenic pairs, B10.A(3R) and B10.A(5R), which received conventional or cloned macrophages by cell transfer. Suppressor T-cell factor (TsF) from C3H----C57BL/6 or C57BL/6----C3H chimera suppressed only donor but not host-type responses of either C3H or C57BL/6, in an antigen-specific fashion. However, if chimera mice were given conventional or cloned macrophages of the host type, the chimera TsF in turn suppressed both the responses of C3H and C57BL/6 mice but not those of the third party, BALB/c, indicating that macrophages are responsible for the acquisition of host restriction specificity. Similarly, B10.A(5R) mice developed I-Jb restricted Ts or TsF when the B10.A(3R) macrophage cell line was injected at the time of antigen priming. The reverse was also true. B10.A(3R) mice did generate I-Jk restricted Ts when they received the B10.A(5R) macrophage cell line. Thus, the results clearly demonstrated that B10.A(3R) or B10.A(5R) mice potentially possessed their ability to express both I-Jk and I-Jb determinants and that repertoires and genetic restriction specificity of Ts and their TsF were acquired at a macrophage level at the time of antigen-priming

  5. NDRG2 is a candidate tumor-suppressor for oral squamous-cell carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Furuta, Hiroshi; Kondo, Yuudai [Division of Oral and Maxillofacial Surgery, Medicine of Sensory and Motor Organs, University of Miyazaki, 5200 Kihara, Kiyotake, Miyazaki-gun, Miyazaki 889-1692 (Japan); Division of Tumor and Cellular Biochemistry, Department of Medical Sciences, Faculty of Medicine, University of Miyazaki, 5200 Kihara, Kiyotake, Miyazaki-gun, Miyazaki 889-1692 (Japan); Nakahata, Shingo; Hamasaki, Makoto [Division of Tumor and Cellular Biochemistry, Department of Medical Sciences, Faculty of Medicine, University of Miyazaki, 5200 Kihara, Kiyotake, Miyazaki-gun, Miyazaki 889-1692 (Japan); Sakoda, Sumio [Division of Oral and Maxillofacial Surgery, Medicine of Sensory and Motor Organs, University of Miyazaki, 5200 Kihara, Kiyotake, Miyazaki-gun, Miyazaki 889-1692 (Japan); Morishita, Kazuhiro, E-mail: kmorishi@med.miyazaki-u.ac.jp [Division of Tumor and Cellular Biochemistry, Department of Medical Sciences, Faculty of Medicine, University of Miyazaki, 5200 Kihara, Kiyotake, Miyazaki-gun, Miyazaki 889-1692 (Japan)

    2010-01-22

    Oral cancer is one of the most common cancers worldwide, and squamous-cell carcinoma (OSCC) is the most common phenotype of oral cancer. Although patients with OSCC have poor survival rates and a high incidence of metastasis, the molecular mechanisms of OSCC development have not yet been elucidated. This study investigated whether N-myc downstream-regulated gene 2 (NDRG2) contributes to the carcinogenesis of OSCC, as NDRG2 is reported to be a candidate tumor-suppressor gene in a wide variety of cancers. The down-regulation of NDRG2 mRNA, which was dependent on promoter methylation, was seen in the majority of OSCC cases and in several cases of precancerous leukoplakia with dysplasia. Induction of NDRG2 expression in an HSC-3/OSCC cell line significantly inhibited cell proliferation and decreased colony formation ability on soft agar. The majority of OSCC cell lines showed an activation of PI3K/Akt signaling, and enforced expression of NDRG2 in HSC-3 cells decreased the level of phosphorylated Akt at Serine 473 (p-Akt). Immunohistochemical p-Akt staining was detected in 56.5% of the OSCC tumors, and 80.4% of the tumors were negative for NDRG2 staining. Moreover, positive p-Akt staining was inversely correlated with decreased NDRG2 expression in OSCC tumors with moderate to poor differentiation (p < 0.005). Therefore, NDRG2 is a candidate tumor-suppressor gene for OSCC development and probably contributes to the tumorigenesis of OSCC partly via the modulation of Akt signaling.

  6. Intragenic suppressor of Osiaa23 revealed a conserved tryptophan residue crucial for protein-protein interactions.

    Directory of Open Access Journals (Sweden)

    Jun Ni

    Full Text Available The Auxin/Indole-3-Acetic Acid (Aux/IAA and Auxin Response Factor (ARF are two important families that play key roles in auxin signal transduction. Both of the families contain a similar carboxyl-terminal domain (Domain III/IV that facilitates interactions between these two families. In spite of the importance of protein-protein interactions among these transcription factors, the mechanisms involved in these interactions are largely unknown. In this study, we isolated six intragenic suppressors of an auxin insensitive mutant, Osiaa23. Among these suppressors, Osiaa23-R5 successfully rescued all the defects of the mutant. Sequence analysis revealed that an amino acid substitution occurred in the Tryptophan (W residue in Domain IV of Osiaa23. Yeast two-hybrid experiments showed that the mutation in Domain IV prevents the protein-protein interactions between Osiaa23 and OsARFs. Phylogenetic analysis revealed that the W residue is conserved in both OsIAAs and OsARFs. Next, we performed site-specific amino acid substitutions within Domain IV of OsARFs, and the conserved W in Domain IV was exchanged by Serine (S. The mutated OsARF(WSs can be released from the inhibition of Osiaa23 and maintain the transcriptional activities. Expression of OsARF(WSs in Osiaa23 mutant rescued different defects of the mutant. Our results suggest a previously unknown importance of Domain IV in both families and provide an indirect way to investigate functions of OsARFs.

  7. Tumor suppressor protein SMAR1 modulates the roughness of cell surface: combined AFM and SEM study

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    Mamgain Hitesh

    2009-10-01

    Full Text Available Abstract Background Imaging tools such as scanning electron microscope (SEM and atomic force microscope (AFM can be used to produce high-resolution topographic images of biomedical specimens and hence are well suited for imaging alterations in cell morphology. We have studied the correlation of SMAR1 expression with cell surface smoothness in cell lines as well as in different grades of human breast cancer and mouse tumor sections. Methods We validated knockdown and overexpression of SMAR1 using RT-PCR as well as Western blotting in human embryonic kidney (HEK 293, human breast cancer (MCF-7 and mouse melanoma (B16F1 cell lines. The samples were then processed for cell surface roughness studies using atomic force microscopy (AFM and scanning electron microscopy (SEM. The same samples were used for microarray analysis as well. Tumors sections from control and SMAR1 treated mice as well as tissues sections from different grades of human breast cancer on poly L-lysine coated slides were used for AFM and SEM studies. Results Tumor sections from mice injected with melanoma cells showed pronounced surface roughness. In contrast, tumor sections obtained from nude mice that were first injected with melanoma cells followed by repeated injections of SMAR1-P44 peptide, exhibited relatively smoother surface profile. Interestingly, human breast cancer tissue sections that showed reduced SMAR1 expression exhibited increased surface roughness compared to the adjacent normal breast tissue. Our AFM data establishes that treatment of cells with SMAR1-P44 results into increase in cytoskeletal volume that is supported by comparative gene expression data showing an increase in the expression of specific cytoskeletal proteins compared to the control cells. Altogether, these findings indicate that tumor suppressor function of SMAR1 might be exhibited through smoothening of cell surface by regulating expression of cell surface proteins. Conclusion Tumor suppressor

  8. PDZ-containing 1 acts as a suppressor of pancreatic cancer by regulating PTEN phosphorylation.

    Science.gov (United States)

    Ma, Qiang; Wu, Xiuxiu; Wu, Jing; Wu, Huanwen; Xiao, Ying; Wang, Lili; Liang, Zhiyong; Liu, Tonghua

    2017-09-22

    Phosphorylation is a recently established cause of phosphatase and tensin homolog (PTEN) gene inactivation, which leads to defect tumour-suppressor function. In pancreatic cancer, this phenomenon has not been reported. Based on database and clinical sample analyses, we found that PTEN phosphorylation occurs in pancreatic ductal adenocarcinoma patient tissues and cell lines, and we aimed to find a method for dephosphorylation. PDZ-containing 1 (PDZK1), a tumour-associated protein that shares its PDZ-binding sequence with the carboxyl-terminal domain of PTEN, was significantly down-regulated in pancreatic cancer as compared to adjacent non-tumour tissues. In vitro , PDZK1 overexpression reversed the proliferation and migration abilities of pancreatic cancer cells and led to significantly decreased PTEN phosphorylation and AKT phosphorylation by interacting with wild-type PTEN. In addition, a transcription factor-activation assay supported that PDZK1 overexpression enhanced the anti-oncogene function of PTEN by regulating the activities of its downstream transcription factors, including p53, NF-κB, and FOXO1. In vivo , nude mice stably over-expressing PDZK1 had lower tumour weights and volumes and showed significantly down-regulated PTEN phosphorylation in xenograft tumour tissues as compared to the control group. Moreover, low PDZK1 expression strongly correlated with advanced stage and poor prognosis of patients with pancreatic ductal adenocarcinoma. In conclusion, our study elucidated the tumour-suppressor role of PDZK1 in pancreatic cancer through down-regulating PTEN phosphorylation, and established PDZK1 as a potential novel prognostic marker for pancreatic cancer.

  9. Modulating glioma-mediated myeloid-derived suppressor cell development with sulforaphane.

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    Ravi Kumar

    Full Text Available Glioblastoma is the most common primary tumor of the brain and has few long-term survivors. The local and systemic immunosuppressive environment created by glioblastoma allows it to evade immunosurveillance. Myeloid-derived suppressor cells (MDSCs are a critical component of this immunosuppression. Understanding mechanisms of MDSC formation and function are key to developing effective immunotherapies. In this study, we developed a novel model to reliably generate human MDSCs from healthy-donor CD14+ monocytes by culture in human glioma-conditioned media. Monocytic MDSC frequency was assessed by flow cytometry and confocal microscopy. The resulting MDSCs robustly inhibited T cell proliferation. A cytokine array identified multiple components of the GCM potentially contributing to MDSC generation, including Monocyte Chemoattractive Protein-1, interleukin-6, interleukin-8, and Macrophage Migration Inhibitory Factor (MIF. Of these, Macrophage Migration Inhibitory Factor is a particularly attractive therapeutic target as sulforaphane, a naturally occurring MIF inhibitor derived from broccoli sprouts, has excellent oral bioavailability. Sulforaphane inhibits the transformation of normal monocytes to MDSCs by glioma-conditioned media in vitro at pharmacologically relevant concentrations that are non-toxic to normal leukocytes. This is associated with a corresponding increase in mature dendritic cells. Interestingly, sulforaphane treatment had similar pro-inflammatory effects on normal monocytes in fresh media but specifically increased immature dendritic cells. Thus, we have used a simple in vitro model system to identify a novel contributor to glioblastoma immunosuppression for which a natural inhibitor exists that increases mature dendritic cell development at the expense of myeloid-derived suppressor cells when normal monocytes are exposed to glioma conditioned media.

  10. Expression of arf tumor suppressor in spermatogonia facilitates meiotic progression in male germ cells.

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    Michelle L Churchman

    2011-07-01

    Full Text Available The mammalian Cdkn2a (Ink4a-Arf locus encodes two tumor suppressor proteins (p16(Ink4a and p19(Arf that respectively enforce the anti-proliferative functions of the retinoblastoma protein (Rb and the p53 transcription factor in response to oncogenic stress. Although p19(Arf is not normally detected in tissues of young adult mice, a notable exception occurs in the male germ line, where Arf is expressed in spermatogonia, but not in meiotic spermatocytes arising from them. Unlike other contexts in which the induction of Arf potently inhibits cell proliferation, expression of p19(Arf in spermatogonia does not interfere with mitotic cell division. Instead, inactivation of Arf triggers germ cell-autonomous, p53-dependent apoptosis of primary spermatocytes in late meiotic prophase, resulting in reduced sperm production. Arf deficiency also causes premature, elevated, and persistent accumulation of the phosphorylated histone variant H2AX, reduces numbers of chromosome-associated complexes of Rad51 and Dmc1 recombinases during meiotic prophase, and yields incompletely synapsed autosomes during pachynema. Inactivation of Ink4a increases the fraction of spermatogonia in S-phase and restores sperm numbers in Ink4a-Arf doubly deficient mice but does not abrogate γ-H2AX accumulation in spermatocytes or p53-dependent apoptosis resulting from Arf inactivation. Thus, as opposed to its canonical role as a tumor suppressor in inducing p53-dependent senescence or apoptosis, Arf expression in spermatogonia instead initiates a salutary feed-forward program that prevents p53-dependent apoptosis, contributing to the survival of meiotic male germ cells.

  11. Identification of a myeloid-derived suppressor cell cystatin-like protein that inhibits metastasis

    Science.gov (United States)

    Boutté, Angela M.; Friedman, David B.; Bogyo, Matthew; Min, Yongfen; Yang, Li; Lin, P. Charles

    2011-01-01

    Myeloid-derived suppressor cells (MDSCs) are significantly increased in cancer patients and tumor bearing-animals. MDSCs infiltrate into tumors and promote tumor invasion and metastasis. To identify the mediator responsible for the prometastatic property of MDSCs, we used proteomics. We found neutrophilic granule protein (NGP) was decreased >2-fold in MDSCs from metastatic 4T1 tumor-bearing mice compared to nonmetastatic 67NR controls. NGP mRNA levels were decreased in bone marrow and in tumor-infiltrating MDSCs by 45 and 66%, respectively, in 4T1 tumor-bearing mice compared to 67NR controls. Interestingly, 4T1-conditioned medium reduced myeloid cell NGP expression by ∼40%, suggesting that a secreted factor mediates gene reduction. Sequence analysis shows a putative cystatin domain in NGP, and biochemical analysis confirms NGP a novel cathepsin inhibitor. It inhibited cathepsin B activity by nearly 40% in vitro. NGP expression in 4T1 tumor cells suppressed cell invasion, delayed primary tumor growth, and greatly reduced lung metastasis in vivo. A 2.8-fold reduction of cathepsin activity was found in tumors expressing NGP compared to controls. NGP significantly reduced tumor angiogenesis to 12.6 from 19.6 and lymphangiogenesis to 4.6 from 9.1 vessels/field. Necrosis was detectable only in NGP-expressing tumors, and the number of apoptotic cells increased to 22.4 from 8.3 in controls. Taken together, this study identifies a negative regulator of tumor metastasis in MDSCs, NGP, which is down-regulated in metastatic conditions. The finding suggests that malignant tumors promote invasion/metastasis not only through up-regulation of proteases but also down-regulation of protease inhibitors.—Boutté, A. M., Friedman, D. B., Bogyo, M., Min, Y., Yang, L., Lin, P. C. Identification of a myeloid-derived suppressor cell cystatin-like protein that inhibits metastasis. PMID:21518852

  12. Immortalized myeloid suppressor cells trigger apoptosis in antigen-activated T lymphocytes.

    Science.gov (United States)

    Apolloni, E; Bronte, V; Mazzoni, A; Serafini, P; Cabrelle, A; Segal, D M; Young, H A; Zanovello, P

    2000-12-15

    We described a generalized suppression of CTL anamnestic responses that occurred in mice bearing large tumor nodules or immunized with powerful recombinant viral immunogens. Immune suppression entirely depended on GM-CSF-driven accumulation of CD11b(+)/Gr-1(+) myeloid suppressor cells (MSC) in secondary lymphoid organs. To further investigate the nature and properties of MSC, we immortalized CD11b(+)/Gr-1(+) cells isolated from the spleens of immunosuppressed mice, using a retrovirus encoding the v-myc and v-raf oncogenes. Immortalized cells expressed monocyte/macrophage markers (CD11b, F4/80, CD86, CD11c), but they differed from previously characterized macrophage lines in their capacities to inhibit T lymphocyte activation. Two MSC lines, MSC-1 and MSC-2, were selected based upon their abilities to inhibit Ag-specific proliferative and functional CTL responses. MSC-1 line was constitutively inhibitory, while suppressive functions of MSC-2 line were stimulated by exposure to the cytokine IL-4. Both MSC lines triggered the apoptotic cascade in Ag-activated T lymphocytes by a mechanism requiring cell-cell contact. Some well-known membrane molecules involved in the activation of apoptotic pathways (e.g., TNF-related apoptosis-inducing ligand, Fas ligand, TNF-alpha) were ruled out as candidate effectors for the suppression mechanism. The immortalized myeloid lines represent a novel, useful tool to shed light on the molecules involved in the differentiation of myeloid-related suppressors as well as in the inhibitory pathway they use to control T lymphocyte activation.

  13. Promoter hypermethylation of KLF4 inactivates its tumor suppressor function in cervical carcinogenesis.

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    Wen-Ting Yang

    Full Text Available OBJECTIVE: The KLF4 gene has been shown to be inactivated in cervical carcinogenesis as a tumor suppressor. However, the mechanism of KLF4 silencing in cervical carcinomas has not yet been identified. DNA methylation plays a key role in stable suppression of gene expression. METHODS: The methylation status of the KLF4 promoter CpG islands was analyzed by bisulfite sequencing (BSQ in tissues of normal cervix and cervical cancer. KLF4 gene expression was detected by RT-PCR, immunohistochemistry and western blot. KLF4 promoter methylation in cervical cancer cell line was determined by BSQ and methylation-specific polymerase chain reaction (MS-PCR. Cell proliferation ability was detected by cell growth curve and MTT assay. RESULTS: The methylated allele was found in 41.90% of 24 cervical cancer tissues but only in 11.11% of 11 normal cervix tissues (P<0.005. KLF4 mRNA levels were significantly reduced in cervical cancer tissues compared with normal cervix tissues (P<0.01 and KLF4 mRNA expression showed a significant negative correlation with the promoter hypermethylation (r = -0.486, P = 0.003. Cervical cancer cell lines also showed a significant negative correlation between KLF4 expression and hypermethylation. After treatment with the demethylating agent 5-Azacytidine (5-Aza, the expression of KLF4 in the cervical cancer cell lines at both mRNA and protein levels was drastically increased, the cell proliferation ability was inhibited and the chemosensitivity for cisplatin was significantly increased. CONCLUSION: KLF4 gene is inactivated by methylation-induced silencing mechanisms in a large subset of cervical carcinomas and KLF4 promoter hypermethylation inactivates the gene's function as a tumor suppressor in cervical carcinogenesis.

  14. DEVELOPMENT OF ANALYTICAL METHODS FOR DETERMINING SUPPRESSOR CONCENTRATION IN THE MCU NEXT GENERATION SOLVENT (NGS)

    Energy Technology Data Exchange (ETDEWEB)

    Taylor-Pashow, K.; Fondeur, F.; White, T.; Diprete, D.; Milliken, C.

    2013-07-31

    Savannah River National Laboratory (SRNL) was tasked with identifying and developing at least one, but preferably two methods for quantifying the suppressor in the Next Generation Solvent (NGS) system. The suppressor is a guanidine derivative, N,N',N"-tris(3,7-dimethyloctyl)guanidine (TiDG). A list of 10 possible methods was generated, and screening experiments were performed for 8 of the 10 methods. After completion of the screening experiments, the non-aqueous acid-base titration was determined to be the most promising, and was selected for further development as the primary method. {sup 1}H NMR also showed promising results from the screening experiments, and this method was selected for further development as the secondary method. Other methods, including {sup 36}Cl radiocounting and ion chromatography, also showed promise; however, due to the similarity to the primary method (titration) and the inability to differentiate between TiDG and TOA (tri-n-ocytlamine) in the blended solvent, {sup 1}H NMR was selected over these methods. Analysis of radioactive samples obtained from real waste ESS (extraction, scrub, strip) testing using the titration method showed good results. Based on these results, the titration method was selected as the method of choice for TiDG measurement. {sup 1}H NMR has been selected as the secondary (back-up) method, and additional work is planned to further develop this method and to verify the method using radioactive samples. Procedures for analyzing radioactive samples of both pure NGS and blended solvent were developed and issued for the both methods.

  15. A study in male and female 5-HT transporter knockout rats : An animal model for anxiety and depression disorders

    NARCIS (Netherlands)

    Olivier, J D A; Van Der Hart, M G C; Van Swelm, R P L; Dederen, P J; Homberg, J R; Cremers, T; Deen, P M T; Cuppen, E; Cools, A R; Ellenbroek, B A

    2008-01-01

    Human studies have shown that a reduction of 5-HT transporter (SERT) increases the vulnerability for anxiety and depression. Moreover, women are more vulnerable to develop depression and anxiety disorders than men. For that reason we hypothesized that homozygous 5-HT transporter knockout rat

  16. Characterization of the serotonin transporter knockout rat : A selective change in the functioning of the serotonergic system

    NARCIS (Netherlands)

    Homberg, J. R.; Olivier, J.D.A.; Smits, B. M. G.; Mul, J. D.; Mudde, J.; Verheul, M.; Nieuwenhuizen, O. F. M.; Cools, A. R.; Ronken, E; Cremers, Thomas; Schoffelmeere, A. N. M.; Ellenbroeik, B. A.; Cuppen, E.

    2007-01-01

    Serotonergic signaling is involved in many neurobiological processes and disturbed 5-HT homeostasis is implicated in a variety of psychiatric and addictive disorders. Here, we describe the functional characterization of the serotonin transporter (SERT) knockout rat model, that is generated by

  17. Altered expression and modulation of activity-regulated cytoskeletal associated protein (Arc) in serotonin transporter knockout rats.

    NARCIS (Netherlands)

    Molteni, R.; Calabrese, F.; Maj, P.F.; Olivier, J.D.A.; Racagni, G.; Ellenbroek, A.A.; Riva, M.A.

    2009-01-01

    A gene variant in the human serotonin transporter (SERT) can increase the vulnerability to mood disorders. SERT knockout animals show similarities to the human condition and represent an important tool to investigate the mechanisms underlying the pathologic condition in humans. Along this line of

  18. Characterization of the serotonin transporter knockout rat: a selective change in the functioning of the serotonergic system.

    NARCIS (Netherlands)

    Homberg, J.R.; Olivier, J.D.A.; Smits, B.M.; Mul, J.D.; Mudde, J.; Verheul, M.; Nieuwenhuizen, O.F.; Cools, A.R.; Ronken, E.; Cremers, T.; Schoffelmeer, A.N.; Ellenbroek, B.A.; Cuppen, E.

    2007-01-01

    Serotonergic signaling is involved in many neurobiological processes and disturbed 5-HT homeostasis is implicated in a variety of psychiatric and addictive disorders. Here, we describe the functional characterization of the serotonin transporter (SERT) knockout rat model, that is generated by

  19. Double blind, placebo controlled trial of two probiotic strains in interleukin 10 knockout mice and mechanistic link with cytokine balance

    NARCIS (Netherlands)

    McCarthy, J.; O'Mahony, L.; O'Callaghan, L.; Sheil, B.; Vaughan, E.E.; Fitzsimons, N.A.; Fitzgibbon, J.; O'Sullivan, G.C.; Kiely, B.; Collins, J.K.; Shanahan, F.

    2003-01-01

    Background: Prophylactic efficacy against colitis following lactobacillus consumption in interleukin 10 (IL-10) knockout ( KO) mice has been reported. Whether this applies equally to other probiotic strains is unknown, and the mechanism is unclear. Aims: ( 1) To compare the effect of feeding

  20. Alterations in apical dendrite bundling in the somatosensory cortex of 5-HT3A receptor knockout mice.

    NARCIS (Netherlands)

    Smit-Rigter, L.A.; Wadman, W.J.; van Hooft, J.A.

    2011-01-01

    In various species and areas of the cerebral cortex, apical dendrites of pyramidal neurons form clusters which extend through several layers of the cortex also known as dendritic bundles. Previously, it has been shown that 5-HT3A receptor knockout mice show hypercomplex apical dendrites of cortical

  1. Raphe serotonin neuron-specific oxytocin receptor knockout reduces aggression without affecting anxiety-like behavior in male mice only

    Science.gov (United States)

    Pagani, Jerome H.; Williams Avram, Sarah K.; Cui, Zhenzhong; Song, June; Mezey, Éva; Senerth, Julia M.; Baumann, Michael H.; Young, W. Scott

    2015-01-01

    Serotonin and oxytocin influence aggressive and anxiety-like behaviors, though it is unclear how the two may interact. That the oxytocin receptor is expressed in the serotonergic raphe nuclei suggests a mechanism by which the two neurotransmitters may cooperatively influence behavior. We hypothesized that oxytocin acts on raphe neurons to influence serotonergically-mediated anxiety-like, aggressive and parental care behaviors. We eliminated expression of the oxytocin receptor in raphe neurons by crossing mice expressing Cre recombinase under control of the serotonin transporter promoter (Slc6a4) with our conditional oxytocin receptor knockout line. The knockout mice generated by this cross are normal across a range of behavioral measures: there are no effects for either sex on locomotion in an open-field, olfactory habituation/dishabituation or, surprisingly, anxiety-like behaviors in the elevated O and plus mazes. There was a profound deficit in male aggression: only one of 11 raphe oxytocin receptor knockouts showed any aggressive behavior, compared to eight of 11 wildtypes. In contrast, female knockouts displayed no deficits in maternal behavior or aggression. Our results show that oxytocin, via its effects on raphe neurons, is a key regulator of resident-intruder aggression in males but not maternal aggression. Furthermore, this reduction in male aggression is quite different from the effects reported previously after forebrain or total elimination of oxytocin receptors. Finally, we conclude that when constitutively eliminated, oxytocin receptors expressed by serotonin cells do not contribute to baseline anxiety-like behaviors or maternal care. PMID:25677455

  2. A study in male and female 5-HT transporter knockout rats: an animal model for anxiety and depression disorders.

    NARCIS (Netherlands)

    Olivier, J.; Van Der Hart, M.G.C.; Van Swelm, R.P.L.; Dederen, P.J.; Homberg, J.R.; Cremers, T.; Deen, P.M.T.; Cuppen, E.; Cools, A.R.; Ellenbroek, B.A.

    2008-01-01

    Human studies have shown that a reduction of 5-HT transporter (SERT) increases the vulnerability for anxiety and depression. Moreover, women are more vulnerable to develop depression and anxiety disorders than men. For that reason we hypothesized that homozygous 5-HT transporter knockout rat

  3. No further loss of dorsal root ganglion cells after axotomy in p75 neurotrophin receptor knockout mice

    DEFF Research Database (Denmark)

    Sørensen, Bodil; Tandrup, Trine; Koltzenburg, Martin

    2003-01-01

    disector techniques. At birth, the total number of DRG neurons was 10,000 ±2,600 in control mice compared with 5,100 ±1,300 in p75 knockout mice. During postnatal development, 1,400 neuronal B-cell bodies were lost in p75 knockouts (2P ± 0.±05) and 1,100 in controls (NS), whereas the A-cell population......The role of the p75 neurotrophin receptor for neuronal survival after nerve crush was studied in L5 dorsal root ganglia (DRG) of knockout mice and controls with assumption-free stereological methods. Numbers of neuronal A- and B-cells were obtained using the optical fractionator and optical...... remained stable. After a sciatic nerve crush, the total neuron loss in controls was 15.4% ±3.5% (2P ±0.05) and 22.7% 5.1% (2P neurons after crush in p75 knockout mice. Neuronal A-cell number was unchanged after...

  4. Acute multi-sgRNA knockdown of KEOPS complex genes reproduces the microcephaly phenotype of the stable knockout zebrafish model.

    Directory of Open Access Journals (Sweden)

    Tilman Jobst-Schwan

    Full Text Available Until recently, morpholino oligonucleotides have been widely employed in zebrafish as an acute and efficient loss-of-function assay. However, off-target effects and reproducibility issues when compared to stable knockout lines have compromised their further use. Here we employed an acute CRISPR/Cas approach using multiple single guide RNAs targeting simultaneously different positions in two exemplar genes (osgep or tprkb to increase the likelihood of generating mutations on both alleles in the injected F0 generation and to achieve a similar effect as morpholinos but with the reproducibility of stable lines. This multi single guide RNA approach resulted in median likelihoods for at least one mutation on each allele of >99% and sgRNA specific insertion/deletion profiles as revealed by deep-sequencing. Immunoblot showed a significant reduction for Osgep and Tprkb proteins. For both genes, the acute multi-sgRNA knockout recapitulated the microcephaly phenotype and reduction in survival that we observed previously in stable knockout lines, though milder in the acute multi-sgRNA knockout. Finally, we quantify the degree of mutagenesis by deep sequencing, and provide a mathematical model to quantitate the chance for a biallelic loss-of-function mutation. Our findings can be generalized to acute and stable CRISPR/Cas targeting for any zebrafish gene of interest.

  5. Studies of an Androgen-Binding Protein Knockout Corroborate a Role for Salivary ABP in Mouse Communication

    Czech Academy of Sciences Publication Activity Database

    Chung, A. G.; Belone, P. M.; Vošlajerová Bímová, Barbora; Karn, R. C.; Laukaitis, C. M.

    2017-01-01

    Roč. 205, č. 4 (2017), s. 1517-1527 ISSN 0016-6731 R&D Projects: GA ČR GA15-13265S Institutional support: RVO:67985904 Keywords : androgen-binding protein * knockout mouse * preference testing Subject RIV: EA - Cell Biology OBOR OECD: Biology (theoretical, mathematical, thermal, cryobiology, biological rhythm), Evolutionary biology Impact factor: 4.556, year: 2016

  6. CD8 Knockout Mice Are Protected from Challenge by Vaccination with WR201, a Live Attenuated Mutant of Brucella melitensis

    Directory of Open Access Journals (Sweden)

    Samuel L. Yingst

    2013-01-01

    Full Text Available CD8+ T cells have been reported to play an important role in defense against B. abortus infection in mouse models. In the present report, we use CD8 knockout mice to further elucidate the role of these cells in protection from B. melitensis infection. Mice were immunized orally by administration of B. melitensis WR201, a purine auxotrophic attenuated vaccine strain, then challenged intranasally with B. melitensis 16M. In some experiments, persistence of WR201 in the spleens of CD8 knockout mice was slightly longer than that in the spleens of normal mice. However, development of anti-LPS serum antibody, antigen-induced production of γ-interferon (IFN-γ by immune splenic lymphocytes, protection against intranasal challenge, and recovery of nonimmunized animals from intranasal challenge were similar between normal and knockout animals. Further, primary Brucella infection was not exacerbated in perforin knockout and Fas-deficient mice and these animals’ anti-Brucella immune responses were indistinguishable from those of normal mice. These results indicate that CD8+ T cells do not play an essential role as either cytotoxic cells or IFN-γ producers, yet they do participate in a specific immune response to immunization and challenge in this murine model of B. melitensis infection.

  7. Knock-Out Serum Replacement and Melatonin Effects on Germ Cell Differentiation in Murine Testicular Explant Cultures

    NARCIS (Netherlands)

    Reda, Ahmed; Albalushi, Halima; Montalvo, Sheyla Cisneros; Nurmio, Mirja; Sahin, Zeliha; Hou, Mi; Geijsen, Niels; Toppari, Jorma; Söder, Olle; Stukenborg, Jan-Bernd

    Finding robust culture conditions for in vitro maturation (IVM) of male germ cells is still a challenge. Recently, a testis organ culture method, using Knockout Serum Replacement (KSR), was suggested as a promising approach. However, the efficiency of that model is still not optimal. Hence, we have

  8. Enhanced proliferation of astrocytes from beta(2)-adrenergic receptor knockout mice is influenced by the IGF system

    NARCIS (Netherlands)

    Chesik, Daniel; Glazenburg, Lisa; De Keyser, Jacques; Wilczak, Nadine

    In the present study, we investigated the IGF system in neonatal astrocytes derived from mice with a targeted disruption of the beta-2 adrenergic receptor (beta(2)AR). beta(2)AR knockout astrocytes demonstrated higher proliferation rates and increased expression of the astrogliotic marker GFAP, as

  9. Brain Region-Specific Effects of cGMP-Dependent Kinase II Knockout on AMPA Receptor Trafficking and Animal Behavior

    Science.gov (United States)

    Kim, Seonil; Pick, Joseph E.; Abera, Sinedu; Khatri, Latika; Ferreira, Danielle D. P.; Sathler, Matheus F.; Morison, Sage L.; Hofmann, Franz; Ziff, Edward B.

    2016-01-01

    Phosphorylation of GluA1, a subunit of AMPA receptors (AMPARs), is critical for AMPAR synaptic trafficking and control of synaptic transmission. cGMP-dependent protein kinase II (cGKII) mediates this phosphorylation, and cGKII knockout (KO) affects GluA1 phosphorylation and alters animal behavior. Notably, GluA1 phosphorylation in the KO…

  10. Modulator of apoptosis 1 (MOAP-1) is a tumor suppressor protein linked to the RASSF1A protein.

    Science.gov (United States)

    Law, Jennifer; Salla, Mohamed; Zare, Alaa; Wong, Yoke; Luong, Le; Volodko, Natalia; Svystun, Orysya; Flood, Kayla; Lim, Jonathan; Sung, Miranda; Dyck, Jason R B; Tan, Chong Teik; Su, Yu-Chin; Yu, Victor C; Mackey, John; Baksh, Shairaz

    2015-10-02

    Modulator of apoptosis 1 (MOAP-1) is a BH3-like protein that plays key roles in cell death or apoptosis. It is an integral partner to the tumor suppressor protein, Ras association domain family 1A (RASSF1A), and functions to activate the Bcl-2 family pro-apoptotic protein Bax. Although RASSF1A is now considered a bona fide tumor suppressor protein, the role of MOAP-1 as a tumor suppressor protein has yet to be determined. In this study, we present several lines of evidence from cancer databases, immunoblotting of cancer cells, proliferation, and xenograft assays as well as DNA microarray analysis to demonstrate the role of MOAP-1 as a tumor suppressor protein. Frequent loss of MOAP-1 expression, in at least some cancers, appears to be attributed to mRNA down-regulation and the rapid proteasomal degradation of MOAP-1 that could be reversed utilizing the proteasome inhibitor MG132. Overexpression of MOAP-1 in several cancer cell lines resulted in reduced tumorigenesis and up-regulation of genes involved in cancer regulatory pathways that include apoptosis (p53, Fas, and MST1), DNA damage control (poly(ADP)-ribose polymerase and ataxia telangiectasia mutated), those within the cell metabolism (IR-α, IR-β, and AMP-activated protein kinase), and a stabilizing effect on microtubules. The loss of RASSF1A (an upstream regulator of MOAP-1) is one of the earliest detectable epigenetically silenced tumor suppressor proteins in cancer, and we speculate that the additional loss of function of MOAP-1 may be a second hit to functionally compromise the RASSF1A/MOAP-1 death receptor-dependent pathway and drive tumorigenesis. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  11. Modulator of Apoptosis 1 (MOAP-1) Is a Tumor Suppressor Protein Linked to the RASSF1A Protein*

    Science.gov (United States)

    Law, Jennifer; Salla, Mohamed; Zare, Alaa; Wong, Yoke; Luong, Le; Volodko, Natalia; Svystun, Orysya; Flood, Kayla; Lim, Jonathan; Sung, Miranda; Dyck, Jason R. B.; Tan, Chong Teik; Su, Yu-Chin; Yu, Victor C.; Mackey, John; Baksh, Shairaz

    2015-01-01

    Modulator of apoptosis 1 (MOAP-1) is a BH3-like protein that plays key roles in cell death or apoptosis. It is an integral partner to the tumor suppressor protein, Ras association domain family 1A (RASSF1A), and functions to activate the Bcl-2 family pro-apoptotic protein Bax. Although RASSF1A is now considered a bona fide tumor suppressor protein, the role of MOAP-1 as a tumor suppressor protein has yet to be determined. In this study, we present several lines of evidence from cancer databases, immunoblotting of cancer cells, proliferation, and xenograft assays as well as DNA microarray analysis to demonstrate the role of MOAP-1 as a tumor suppressor protein. Frequent loss of MOAP-1 expression, in at least some cancers, appears to be attributed to mRNA down-regulation and the rapid proteasomal degradation of MOAP-1 that could be reversed utilizing the proteasome inhibitor MG132. Overexpression of MOAP-1 in several cancer cell lines resulted in reduced tumorigenesis and up-regulation of genes involved in cancer regulatory pathways that include apoptosis (p53, Fas, and MST1), DNA damage control (poly(ADP)-ribose polymerase and ataxia telangiectasia mutated), those within the cell metabolism (IR-α, IR-β, and AMP-activated protein kinase), and a stabilizing effect on microtubules. The loss of RASSF1A (an upstream regulator of MOAP-1) is one of the earliest detectable epigenetically silenced tumor suppressor proteins in cancer, and we speculate that the additional loss of function of MOAP-1 may be a second hit to functionally compromise the RASSF1A/MOAP-1 death receptor-dependent pathway and drive tumorigenesis. PMID:26269600

  12. Identification of a third protein 4.1 tumor suppressor, protein 4.1R, in meningioma pathogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Robb, Victoria A.; Li, Wen; Gascard, Philippe; Perry, Arie; Mohandas, Narla; Gutmann, David H.

    2003-06-11

    Meningiomas are common tumors of the central nervous system, however, the mechanisms under lying their pathogenesis are largely undefined. Two members of the Protein 4.1 super family, the neuro fibromatosis 2 (NF2) gene product (merlin/schwannomin) and Protein 4.1B have been implicated as meningioma tumor suppressors. In this report, we demonstrate that another Protein 4.1 family member, Protein 4.1R, also functions as a meningioma tumor suppressor. Based on the assignment of the Protein 4.1R gene to chromosome 1p32-36, a common region of deletion observed in meningiomas, we analyzed Protein 4.1R expression in meningioma cell lines and surgical tumor specimens. We observed loss of Protein 4.1R protein expression in two meningioma cell lines (IOMM-Lee, CH157-MN) by Western blotting as well as in 6 of 15 sporadic meningioma as by immuno histo chemistry (IHC). Analysis of a subset of these sporadic meningiomas by fluorescent in situ hybridization (FISH) with a Protein 4.1R specific probe demonstrated 100 percent concordance with the IHC results. In support of a meningioma tumor suppressor function, over expression of Protein 4.1R resulted in suppression of IOMM-Lee and CH157MN cell proliferation. Similar to the Protein 4.1B and merlin meningioma tumor suppressors, Protein 4.1R localization in the membrane fraction increased significantly under conditions of growth arrest in vitro. Lastly, Protein 4.1R interacted with some known merlin/Protein 4.1B interactors such as CD44 and bII-spectrin, but did not associate with the Protein 4.1B interactors 14-3-3 and PRMT3 or the merlin binding proteins SCHIP-1 and HRS. Collectively, these results suggest that Protein 4.1R functions as an important tumor suppressor important in the molecular pathogenesis of meningioma.

  13. Regulation of dopamine presynaptic markers and receptors in the striatum of DJ-1 and Pink1 knockout rats

    Science.gov (United States)

    Sun, Jianjun; Kouranova, Evguenia; Cui, Xiaoxia; Mach, Robert H.; Xu, Jinbin

    2014-01-01

    Pathogenic autosomal recessive mutations in the DJ-1 (Park7) or the PTEN-induced putative kinase 1 (Pink1 or PARK6) genes are associated with familial Parkinson’s disease (PD). It is not well known regarding the pathological mechanisms involving the DJ-1 and Pink1 mutations. Here we characterized DJ-1 and Pink1 knockout rats both through expression profiling and using quantitative autoradiography to measure the densities of the dopamine D1, D2, D3 receptors, vesicular monoamine transporter type-2 (VMAT2) and dopamine transporter (DAT) in the striatum of transgenic rats and wild type controls. Expression profiling with a commercially available array of 84 genes known to be involved in PD indicated that only the target gene was significantly downregulated in each transgenic rat model. D1 receptor, VMAT2, and DAT were measured using [3H]SCH23390, [3H]dihydrotetrabenazine, and [3H]WIN35428, respectively. No significant changes were observed in the density of DAT in either model. Although the densities of VMAT2 and D1 receptor were unchanged in Pink1 knockout, but both were increased in DJ-1 knockout rats. The densities of D2 and D3 receptors, determined by mathematical analysis of binding of radioligands [3H]WC-10 and [3H]raclopride, were significantly increased in both knockout models. These distinctive changes in the expression of dopamine presynaptic markers and receptors in the striatum may reflect different compensatory regulation of dopamine system in DJ-1 versus Pink1 knockout rat models of familial PD. PMID:24157858

  14. Remyelination in experimentally demyelinated connexin 32 KnockOut mice Remielinização em camundongos KnockOut para conexina 32 desmielinizados experimentalmente

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    Adriano Tony Ramos

    2009-06-01

    Full Text Available The aim of this study was to evaluate the role of connexin 32 (Cx 32 during remyelination of the peripheral nervous system, through a local injection of either 0,1% ethidium bromide solution or saline in the sciatic nerve of Cx 32 knockout mice. Euthanasia was performed ranging from 1, 2, 3, 7, 15, 21 to 30 days after injection. Histochemical, immunohistochemical, immunofluorescence and transmission electron microscopical techniques were used to analyze the development of the lesions. Within the sciatic nerves, Schwann cells initially showed signs of intoxication and rejected their sheaths; after seven days, some thin newly formed myelin sheaths with uneven compactness and redundant loops (tomacula were conspicuous. We concluded that the regeneration of lost myelin sheaths within the PNS followed the pattern already reported for this model in other laboratory species. Therefore, these results suggest that absence of Cx 32 did not interfere with the normal pattern of remyelination in this model in young mice.Este estudo visou avaliar o papel da conexina 32 (Cx 32 durante a remielinização no sistema nervoso periférico. Uma injeção local de 0,1% de solução de brometo de etídio foi realizada no nervo ciático de camundongos deletados para a Cx 32, com eutanásia dos animais aos 1, 2, 3, 7, 15, 21 e 30 dias pós-injeção. Avaliações histoquímicas, imunoistoquímicas, por imunofluorescência e por microscopia eletrônica de transmissão foram utilizadas na análise do desenvolvimento das lesões. Nos nervos ciáticos, células de Schwann mostraram inicialmente sinais de intoxicação e rejeitaram suas bainhas. Após sete dias, observaram-se finas bainhas neoformadas, com compactação desigual e alças redundantes (tomácula. Conclui-se que a regeneração de bainhas de mielina perdidas no SNP seguiu o padrão já relatado deste modelo em outras espécies de laboratório. Portanto, estes resultados sugerem que a ausência da Cx 32 n

  15. Surge suppressors devices application for protection of consumer head boxes; Aplicacao de supressores de surtos para a protecao da entrada de consumidores

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Jose Mario Moraes e; Ravaglio, Marcelo Antonio; Schaefer, Jose Carlos [Instituto de Tecnologia para o Desenvolvimento (LACTEC), Curitiba, PR (Brazil). Unidade de Alta Tensao]. E-mails: zemario@lactec.org.br; marcelo@lactec.org.br; schaefer@lactec.org.br; Biazon, Rodolfo B.; Barbosa Junior, Lari; Ferreira Junior, Homero [Companhia Luz e Forca Santa Cruz, SP (Brazil)]. E-mails: rbiazon@santacruz.srv.br; hferreira@santacruz.srv.br; lbarbosa@santacruz.srv.br

    2002-07-01

    This paper presents the main results obtained from a joint project developed by the LACTEC and Santa Cruz Light and Power Company for validation the using of surge suppressors equipment installed at the low voltage consumer head boxes. The project proposed the implementation of a atmospheric discharges first protection of the consumer equipment. The work analysed surge suppressors from different known competent manufacturers in the market. The suppressors has been evaluated in the LACTEC high voltage laboratory, and in the CLFSC distribution system for a period of one year started in August 2000.

  16. Unique nuclear vacuoles in the motor neurons of conditional ADAR2-knockout mice.

    Science.gov (United States)

    Sasaki, Shoichi; Takenari Yamashita; Hideyama, Takuto; Kwak, Shin

    2014-03-06

    A reduction in adenosine deaminase acting on RNA 2 (ADAR2) activity causes the death of spinal motor neurons specifically via the GluA2 Q/R site-RNA editing failure in sporadic amyotrophic lateral sclerosis (ALS). We studied, over time, the spinal cords of ADAR2-knockout mice, which are the mechanistic model mice for sporadic ALS, using homozygous ADAR2(flox/flox)/VAChT-Cre.Fast (AR2), homozygous ADAR2(flox/flox)/VAChT-Cre.Slow (AR2Slow), and heterozygous ADAR2(flox/+)/VAChT-Cre.Fast (AR2H) mice. The conditional ADAR2-knockout mice were divided into 3 groups by stage: presymptomatic (AR2H mice), early symptomatic (AR2 mice, AR2H mice) and late symptomatic (AR2Slow mice). Light-microscopically, some motor neurons in AR2 and AR2H mice (presymptomatic) showed simple neuronal atrophy and astrogliosis, and AR2H (early symptomatic) and AR2Slow mice often showed vacuoles predominantly in motor neurons. The number of vacuole-bearing anterior horn neurons decreased with the loss of anterior horn neurons in AR2H mice after 40 weeks of age. Electron-microscopically, in AR2 mice, while the cytoplasm of normal-looking motor neurons was almost always normal-appearing, the interior of dendrites was frequently loose and disorganized. In AR2H and AR2Slow mice, large vacuoles without a limiting membrane were observed in the anterior horns, preferentially in the nuclei of motor neurons, astrocytes and oligodendrocytes. Nuclear vacuoles were not observed in AR2res (ADAR2(flox/flox)/VAChT-Cre.Fast/GluR-B(R/R)) mice, in which motor neurons express edited GluA2 in the absence of ADAR2. These findings suggest that ADAR2-reduction is associated with progressive deterioration of nuclear architecture, resulting in vacuolated nuclei due to a Ca(2+)-permeable AMPA receptor-mediated mechanism. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. The Pain Genes Database: An interactive web browser of pain-related transgenic knockout studies.

    Science.gov (United States)

    Lacroix-Fralish, Michael L; Ledoux, Jean B; Mogil, Jeffrey S

    2007-09-01

    The transgenic knockout mouse is one of the most important tools of modern biology, and commonly employed by pain researchers to examine the function of genes of interest. Over 400 papers, at a current rate of >60 papers per year, have been published to date describing a statistically significant behavioral pain "phenotype" resulting from the null mutation of a single gene. The standard literature review format is incapable of providing a sufficiently broad and up-to-date overview of the field. We have therefore constructed the Pain Genes Database, an interactive, web-based data browser designed to allow easy access to and analysis of the published pain-related phenotypes of mutant mice (over 200 different mutants at the date of submission). Manuscripts describing results of pain-relevant knockout studies were identified via Medline search. Manuscripts were included in the database if they described the testing of a spontaneous or genetically engineered mutant mouse with null expression of a single gene on a behavioral assay of acute or tonic nociception, injury- or stimulus-induced hypersensitivity (i.e., allodynia or hyperalgesia), or drug- or stress-induced inhibition of nociception (i.e., analgesia), and reported at least one statistically significant difference between the mutant mice and their simultaneously tested wildtype controls. The database features two levels of exploration, one allowing the identification of genes by name, acronym, genomic position or "summary" phenotype, and the other allowing in-depth browsing, paper-by-paper, of specific phenotypes and test parameters. Links to genetic databases and Medline abstracts are provided for each gene and paper. It is our intention to update the database continually based on weekly Medline searches. This database should provide pain researchers with a useful and easy-to-use tool for the generation of novel hypotheses regarding the roles of genes and their protein products in pain processing and modulation

  18. Global analysis of gene expression in the developing brain of Gtf2ird1 knockout mice.

    Directory of Open Access Journals (Sweden)

    Jennifer O'Leary

    Full Text Available Williams-Beuren Syndrome (WBS is a neurodevelopmental disorder caused by a hemizygous deletion of a 1.5 Mb region on chromosome 7q11.23 encompassing 26 genes. One of these genes, GTF2IRD1, codes for a putative transcription factor that is expressed throughout the brain during development. Genotype-phenotype studies in patients with atypical deletions of 7q11.23 implicate this gene in the neurological features of WBS, and Gtf2ird1 knockout mice show reduced innate fear and increased sociability, consistent with features of WBS. Multiple studies have identified in vitro target genes of GTF2IRD1, but we sought to identify in vivo targets in the mouse brain.We performed the first in vivo microarray screen for transcriptional targets of Gtf2ird1 in brain tissue from Gtf2ird1 knockout and wildtype mice at embryonic day 15.5 and at birth. Changes in gene expression in the mutant mice were moderate (0.5 to 2.5 fold and of candidate genes with altered expression verified using real-time PCR, most were located on chromosome 5, within 10 Mb of Gtf2ird1. siRNA knock-down of Gtf2ird1 in two mouse neuronal cell lines failed to identify changes in expression of any of the genes identified from the microarray and subsequent analysis showed that differences in expression of genes on chromosome 5 were the result of retention of that chromosome region from the targeted embryonic stem cell line, and so were dependent upon strain rather than Gtf2ird1 genotype. In addition, specific analysis of genes previously identified as direct in vitro targets of GTF2IRD1 failed to show altered expression.We have been unable to identify any in vivo neuronal targets of GTF2IRD1 through genome-wide expression analysis, despite widespread and robust expression of this protein in the developing rodent brain.

  19. Reconstructing gene-regulatory networks from time series, knock-out data, and prior knowledge

    Directory of Open Access Journals (Sweden)

    Timmer Jens

    2007-02-01

    Full Text Available Abstract Background Cellular processes are controlled by gene-regulatory networks. Several computational methods are currently used to learn the structure of gene-regulatory networks from data. This study focusses on time series gene expression and gene knock-out data in order to identify the underlying network structure. We compare the performance of different network reconstruction methods using synthetic data generated from an ensemble of reference networks. Data requirements as well as optimal experiments for the reconstruction of gene-regulatory networks are investigated. Additionally, the impact of prior knowledge on network reconstruction as well as the effect of unobserved cellular processes is studied. Results We identify linear Gaussian dynamic Bayesian networks and variable selection based on F-statistics as suitable methods for the reconstruction of gene-regulatory networks from time series data. Commonly used discrete dynamic Bayesian networks perform inferior and this result can be attributed to the inevitable information loss by discretization of expression data. It is shown that short time series generated under transcription factor knock-out are optimal experiments in order to reveal the structure of gene regulatory networks. Relative to the level of observational noise, we give estimates for the required amount of gene expression data in order to accurately reconstruct gene-regulatory networks. The benefit of using of prior knowledge within a Bayesian learning framework is found to be limited to conditions of small gene expression data size. Unobserved processes, like protein-protein interactions, induce dependencies between gene expression levels similar to direct transcriptional regulation. We show that these dependencies cannot be distinguished from transcription factor mediated gene regulation on the basis of gene expression data alone. Conclusion Currently available data size and data quality make the reconstruction of

  20. Exposure to low-dose rotenone precipitates synaptic plasticity alterations in PINK1 heterozygous knockout mice.

    Science.gov (United States)

    Martella, G; Madeo, G; Maltese, M; Vanni, V; Puglisi, F; Ferraro, E; Schirinzi, T; Valente, E M; Bonanni, L; Shen, J; Mandolesi, G; Mercuri, N B; Bonsi, P; Pisani, A

    2016-07-01

    Heterozygous mutations in the PINK1 gene are considered a susceptibility factor to develop early-onset Parkinson's disease (PD), as supported by dopamine hypometabolism in asymptomatic mutation carriers and subtle alterations of dopamine-dependent striatal synaptic plasticity in heterozygous PINK1 knockout (PINK1(+/-)) mice. The aim of the present study was to investigate whether exposure to low-dose rotenone of heterozygous PINK1(+/-) mice, compared to their wild-type PINK1(+/+) littermates, could impact on dopamine-dependent striatal synaptic plasticity, in the absence of apparent structural alterations. Mice were exposed to a range of concentrations of rotenone (0.01-1mg/kg). Chronic treatment with concentrations of rotenone up to 0.8mg/kg did not cause manifest neuronal loss or changes in ATP levels both in the striatum or substantia nigra of PINK1(+/-) and PINK1(+/+) mice. Moreover, rotenone (up to 0.8mg/kg) treatment did not induce mislocalization of the mitochondrial membrane protein Tom20 and release of cytochrome c in PINK1(+/-) striata. Accordingly, basic electrophysiological properties of nigral dopaminergic and striatal medium spiny neurons (MSNs) were normal. Despite the lack of gross alterations in neuronal viability in chronically-treated PINK1(+/-), a complete loss of both long-term depression (LTD) and long-term potentiation (LTP) was recorded in MSNs from PINK1(+/-) mice treated with a low rotenone (0.1mg/kg) concentration. Even lower concentrations (0.01mg/kg) blocked LTP induction in heterozygous PINK1(+/-) MSNs compared to PINK1(+/+) mice. Of interest, chronic pretreatment with the antioxidants alpha-tocopherol and Trolox, a water-soluble analog of vitamin E and powerful antioxidant, rescued synaptic plasticity impairment, confirming that, at the doses we utilized, rotenone did not induce irreversible alterations. In this model, chronic exposure to low-doses of rotenone was not sufficient to alter mitochondrial integrity and ATP production, but

  1. Genistein up-regulates tumor suppressor microRNA-574-3p in prostate cancer.

    Directory of Open Access Journals (Sweden)

    Takeshi Chiyomaru

    Full Text Available Genistein has been shown to inhibit cancers both in vitro and in vivo, by altering the expression of several microRNAs (miRNAs. In this study, we focused on tumor suppressor miRNAs regulated by genistein and investigated their function in prostate cancer (PCa and target pathways. Using miRNA microarray analysis and real-time RT-PCR we observed that miR-574-3p was significantly up-regulated in PCa cells treated with genistein compared with vehicle control. The expression of miR-574-3p was significantly lower in PCa cell lines and clinical PCa tissues compared with normal prostate cells (RWPE-1 and adjacent normal tissues. Low expression level of miR-574-3p was correlated with advanced tumor stage and higher Gleason score in PCa specimens. Re-expression of miR-574-3p in PCa cells significantly inhibited cell proliferation, migration and invasion in vitro and in vivo. miR-574-3p restoration induced apoptosis through reducing Bcl-xL and activating caspase-9 and caspase-3. Using GeneCodis software analysis, several pathways affected by miR-574-3p were identified, such as 'Pathways in cancer', 'Jak-STAT signaling pathway', and 'Wnt signaling pathway'. Luciferase reporter assays demonstrated that miR-574-3p directly binds to the 3' UTR of several target genes (such as RAC1, EGFR and EP300 that are components of 'Pathways in cancer'. Quantitative real-time PCR and Western analysis showed that the mRNA and protein expression levels of the three target genes in PCa cells were markedly down-regulated with miR-574-3p. Loss-of-function studies demonstrated that the three target genes significantly affect cell proliferation, migration and invasion in PCa cell lines. Our results show that genistein up-regulates tumor suppressor miR-574-3p expression targeting several cell signaling pathways. These findings enhance understanding of how genistein regulates with miRNA in PCa.

  2. Is the gene encoding Chibby implicated as a tumour suppressor in colorectal cancer ?

    International Nuclear Information System (INIS)

    Gad, Sophie; Teboul, David; Lièvre, Astrid; Goasguen, Nicolas; Berger, Anne; Beaune, Philippe; Laurent-Puig, Pierre

    2004-01-01

    A novel member of the Wnt signalling pathway, Chibby, was recently identified. This protein inhibits Wnt/β-catenin mediated transcriptional activation by competing with Lef-1 (the transcription factor and target of β-catenin) to bind to β-catenin. This suggests that Chibby could be a tumour suppressor protein. The C22orf2 gene coding Chibby is located on chromosome 22, a region recurrently lost in colorectal cancer. Activation of the Wnt pathway is a major feature of colorectal cancer and occurs through inactivation of APC or activation of β-catenin. All of this led us to analyse the possible implication of Chibby in colorectal carcinogenesis. First, 36 tumour and matched normal colonic mucosa DNA were genotyped with five microsatellite markers located on chromosome 22 to search for loss of heterozygosity. Then, mutation screening of the C22orf2 coding sequence and splice sites was performed in the 36 tumour DNA. Finally, expression of Chibby was analysed by quantitative RT-PCR on 10 patients, 4 with loss of heterozygosity (LOH) on chromosome 22. Loss of heterozygosity involving the C22orf2 region was detected in 11 out of 36 patients (30%). Sequencing analysis revealed a known variant, rs3747174, in exon 5: T321C leading to a silent amino acid polymorphism A107A. Allelic frequencies were 0.69 and 0.31 for T and C variants respectively. No other mutation was detected. Among the 10 patients studied, expression analysis revealed that Chibby is overexpressed in 2 tumours and underexpressed in 1. No correlations were found with 22q LOH status. As no somatic mutation was detected in C22orf2 in 36 colorectal tumour DNA, our results do not support the implication of Chibby as a tumour suppressor in colorectal carcinogenesis. This was supported by the absence of underexpression of Chibby among the tumour samples with 22q LOH. The implication of other Wnt pathway members remains to be identified to explain the part of colorectal tumours without mutation in APC and β-catenin

  3. The human LIS1 is downregulated in hepatocellular carcinoma and plays a tumor suppressor function

    Energy Technology Data Exchange (ETDEWEB)

    Xing, Zhen; Tang, Xin; Gao, Yuan; Da, Liang; Song, Hai; Wang, Suiquan [State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai (China); Tiollais, Pierre [Unite' d' Organisation Nucleaire et Oncogenese, INSERM U.579, Institut Pasteur, Paris (France); Li, Tsaiping [State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai (China); Zhao, Mujun, E-mail: mjzhao@sibs.ac.cn [State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai (China)

    2011-06-03

    Highlights: {yields} LIS1 mRNA and protein levels are decreased in 70% HCC tissues. {yields} Downregulation of LIS1 expression induces oncogenic transformation of QSG7701 and NIH3T3 cells in vitro and in vivo. {yields} LIS1 downregulation leads to mitotic errors including spindle and chromosome defects. {yields} Ectopic expression of LIS1 could significantly inhibit HCC cell proliferation and colony formation. {yields} Our results suggest that LIS1 plays a potential tumor suppressor role in the development and progression of HCC. -- Abstract: The human lissencephaly-1 gene (LIS1) is a disease gene responsible for Miller-Dieker lissencephaly syndrome (MDL). LIS1 gene is located in the region of chromosome 17p13.3 that is frequency deleted in MDL patients and in human liver cancer cells. However, the expression and significance of LIS1 in liver cancer remain unknown. Here, we investigated the expression of LIS1 in hepatocellular carcinoma (HCC) tissues by real-time PCR, Western blot, and immunohistochemistry. The results indicated that the mRNA and protein levels of LIS1 were downregulated in about 70% of HCC tissues, and this downregulation was significantly associated with tumor progression. Functional studies showed that the reduction of LIS1 expression in the normal human liver cell line QSG7701 or the mouse fibroblast cell line NIH3T3 by shRNA resulted in colony formation in soft agar and xenograft tumor formation in nude mice, demonstrating that a decrease in the LIS1 level can promote the oncogenic transformation of cells. We also observed that the phenotypes of LIS1-knockdown cells displayed various defective mitotic structures, suggesting that the mechanism by which reduced LIS1 levels results in tumorigenesis is associated with its role in mitosis. Furthermore, we demonstrated that ectopic expression of LIS1 could significantly inhibit HCC cell proliferation and colony formation. Our results suggest that LIS1 plays a potential tumor suppressor role in the

  4. Tumor Suppressor p53 Stimulates the Expression of Epstein-Barr Virus Latent Membrane Protein 1.

    Science.gov (United States)

    Wang, Qianli; Lingel, Amy; Geiser, Vicki; Kwapnoski, Zachary; Zhang, Luwen

    2017-10-15

    Epstein-Barr virus (EBV) is associated with multiple human malignancies. EBV latent membrane protein 1 (LMP1) is required for the efficient transformation of primary B lymphocytes in vitro and possibly in vivo The tumor suppressor p53 plays a seminal role in cancer development. In some EBV-associated cancers, p53 tends to be wild type and overly expressed; however, the effects of p53 on LMP1 expression is not clear. We find LMP1 expression to be associated with p53 expression in EBV-transformed cells under physiological and DNA damaging conditions. DNA damage stimulates LMP1 expression, and p53 is required for the stimulation. Ectopic p53 stimulates endogenous LMP1 expression. Moreover, endogenous LMP1 blocks DNA damage-mediated apoptosis. Regarding the mechanism of p53-mediated LMP1 expression, we find that interferon regulatory factor 5 (IRF5), a direct target of p53, is associated with both p53 and LMP1. IRF5 binds to and activates a LMP1 promoter reporter construct. Ectopic IRF5 increases the expression of LMP1, while knockdown of IRF5 leads to reduction of LMP1. Furthermore, LMP1 blocks IRF5-mediated apoptosis in EBV-infected cells. All of the data suggest that cellular p53 stimulates viral LMP1 expression, and IRF5 may be one of the factors for p53-mediated LMP1 stimulation. LMP1 may subsequently block DNA damage- and IRF5-mediated apoptosis for the benefits of EBV. The mutual regulation between p53 and LMP1 may play an important role in EBV infection and latency and its related cancers. IMPORTANCE The tumor suppressor p53 is a critical cellular protein in response to various stresses and dictates cells for various responses, including apoptosis. This work suggests that an Epstein-Bar virus (EBV) principal viral oncogene is activated by cellular p53. The viral oncogene blocks p53-mediated adverse effects during viral infection and transformation. Therefore, the induction of the viral oncogene by p53 provides a means for the virus to cope with infection and

  5. Targeting myeloid-derived suppressor cells augments antitumor activity against lung cancer

    Directory of Open Access Journals (Sweden)

    Srivastava MK

    2012-10-01

    Full Text Available Minu K Srivastava,1,2 Li Zhu,1,2 Marni Harris-White,2 Min Huang,1–3 Maie St John,1,3 Jay M Lee,1,3 Ravi Salgia,4 Robert B Cameron,1,3,5 Robert Strieter,6 Steven Dubinett,1–3 Sherven Sharma1–31Department of Medicine, UCLA Lung Cancer Research Program, David Geffen School of Medicine at UCLA, Los Angeles, CA, 2Molecular Gene Medicine Laboratory, Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, 3Jonsson Comprehensive Cancer Center, David Geffen School of Medicine at UCLA, Los Angeles, CA, 4Department of Medicine, University of Chicago, Chicago, IL, 5Department of Surgery, Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, 6Department of Medicine, University of Virginia, Charlottesville, VA, USAAbstract: Lung cancer evades host immune surveillance by dysregulating inflammation. Tumors and their surrounding stromata produce growth factors, cytokines, and chemokines that recruit, expand, and/or activate myeloid-derived suppressor cells (MDSCs. MDSCs regulate immune responses and are frequently found in malignancy. In this review the authors discuss tumor-MDSC interactions that suppress host antitumor activities and the authors' recent findings regarding MDSC depletion that led to improved therapeutic vaccination responses against lung cancer. Despite the identification of a repertoire of tumor antigens, hurdles persist for immune-based anticancer therapies. It is likely that combined therapies that address the multiple immune deficits in cancer patients will be required for effective therapy. MDSCs play a major role in the suppression of T-cell activation and they sustain tumor growth, proliferation, and metastases. Regulation of MDSC recruitment, differentiation or expansion, and inhibition of the MDSC suppressive function with pharmacologic agents will be useful in the control of cancer growth and progression. Pharmacologic agents that regulate MDSCs may be more effective when combined with

  6. The human LIS1 is downregulated in hepatocellular carcinoma and plays a tumor suppressor function

    International Nuclear Information System (INIS)

    Xing, Zhen; Tang, Xin; Gao, Yuan; Da, Liang; Song, Hai; Wang, Suiquan; Tiollais, Pierre; Li, Tsaiping; Zhao, Mujun

    2011-01-01

    Highlights: → LIS1 mRNA and protein levels are decreased in 70% HCC tissues. → Downregulation of LIS1 expression induces oncogenic transformation of QSG7701 and NIH3T3 cells in vitro and in vivo. → LIS1 downregulation leads to mitotic errors including spindle and chromosome defects. → Ectopic expression of LIS1 could significantly inhibit HCC cell proliferation and colony formation. → Our results suggest that LIS1 plays a potential tumor suppressor role in the development and progression of HCC. -- Abstract: The human lissencephaly-1 gene (LIS1) is a disease gene responsible for Miller-Dieker lissencephaly syndrome (MDL). LIS1 gene is located in the region of chromosome 17p13.3 that is frequency deleted in MDL patients and in human liver cancer cells. However, the expression and significance of LIS1 in liver cancer remain unknown. Here, we investigated the expression of LIS1 in hepatocellular carcinoma (HCC) tissues by real-time PCR, Western blot, and immunohistochemistry. The results indicated that the mRNA and protein levels of LIS1 were downregulated in about 70% of HCC tissues, and this downregulation was significantly associated with tumor progression. Functional studies showed that the reduction of LIS1 expression in the normal human liver cell line QSG7701 or the mouse fibroblast cell line NIH3T3 by shRNA resulted in colony formation in soft agar and xenograft tumor formation in nude mice, demonstrating that a decrease in the LIS1 level can promote the oncogenic transformation of cells. We also observed that the phenotypes of LIS1-knockdown cells displayed various defective mitotic structures, suggesting that the mechanism by which reduced LIS1 levels results in tumorigenesis is associated with its role in mitosis. Furthermore, we demonstrated that ectopic expression of LIS1 could significantly inhibit HCC cell proliferation and colony formation. Our results suggest that LIS1 plays a potential tumor suppressor role in the development and

  7. New insight into the role of the β3 subunit of the GABAA-R in development, behavior, body weight regulation, and anesthesia revealed by conditional gene knockout

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    Hileman Stanley M

    2007-10-01

    Full Text Available Abstract Background The β3 subunit of the γ-aminobutyric acid type A receptor (GABAA-R has been reported to be important for palate formation, anesthetic action, and normal nervous system function. This subunit has also been implicated in the pathogenesis of Angelman syndrome and autism spectrum disorder. To further investigate involvement of this subunit, we previously produced mice with a global knockout of β3. However, developmental abnormalities, compensation, reduced viability, and numerous behavioral abnormalities limited the usefulness of that murine model. To overcome many of these limitations, a mouse line with a conditionally inactivated β3 gene was engineered. Results Gene targeting and embryonic stem cell technologies were used to create mice in which exon 3 of the β3 subunit was flanked by loxP sites (i.e., floxed. Crossing the floxed β3 mice to a cre general deleter mouse line reproduced the phenotype of the previously described global knockout. Pan-neuronal knockout of β3 was achieved by crossing floxed β3 mice to Synapsin I-cre transgenic mice. Palate development was normal in pan-neuronal β3 knockouts but ~61% died as neonates. Survivors were overtly normal, fertile, and were less sensitive to etomidate. Forebrain selective knockout of β3 was achieved using α CamKII-cre transgenic mice. Palate development was normal in forebrain selective β3 knockout mice. These knockouts survived the neonatal period, but ~30% died between 15–25 days of age. Survivors had reduced reproductive fitness, reduced sensitivity to etomidate, were hyperactive, and some became obese. Conclusion Conditional inactivation of the β3 gene revealed novel insight into the function of this GABAA-R subunit. The floxed β3 knockout mice described here will be very useful for conditional knockout studies to further investigate the role of the β3 subunit in development, ethanol and anesthetic action, normal physiology, and pathophysiologic processes.

  8. Testing the role of predicted gene knockouts in human anthropometric trait variation

    Science.gov (United States)

    Lessard, Samuel; Manning, Alisa K.; Low-Kam, Cécile; Auer, Paul L.; Giri, Ayush; Graff, Mariaelisa; Schurmann, Claudia; Yaghootkar, Hanieh; Luan, Jian'an; Esko, Tonu; Karaderi, Tugce; Bottinger, Erwin P.; Lu, Yingchang; Carlson, Chris; Caulfield, Mark; Dubé, Marie-Pierre; Jackson, Rebecca D.; Kooperberg, Charles; McKnight, Barbara; Mongrain, Ian; Peters, Ulrike; Reiner, Alex P.; Rhainds, David; Sotoodehnia, Nona; Hirschhorn, Joel N.; Scott, Robert A.; Munroe, Patricia B.; Frayling, Timothy M.; Loos, Ruth J.F.; North, Kari E.; Edwards, Todd L.; Tardif, Jean-Claude; Lindgren, Cecilia M.; Lettre, Guillaume

    2016-01-01

    Although the role of complete gene inactivation by two loss-of-function mutations inherited in trans is well-established in recessive Mendelian diseases, we have not yet explored how such gene knockouts (KOs) could influence complex human phenotypes. Here, we developed a statistical framework to test the association between gene KOs and quantitative human traits. Our method is flexible, publicly available, and compatible with common genotype format files (e.g. PLINK and vcf). We characterized gene KOs in 4498 participants from the NHLBI Exome Sequence Project (ESP) sequenced at high coverage (>100×), 1976 French Canadians from the Montreal Heart Institute Biobank sequenced at low coverage (5.7×), and >100 000 participants from the Genetic Investigation of ANthropometric Traits (GIANT) Consortium genotyped on an exome array. We tested associations between gene KOs and three anthropometric traits: body mass index (BMI), height and BMI-adjusted waist-to-hip ratio (WHR). Despite our large sample size and multiple datasets available, we could not detect robust associations between specific gene KOs and quantitative anthropometric traits. Our results highlight several limitations and challenges for future gene KO studies in humans, in particular when there is no prior knowledge on the phenotypes that might be affected by the tested gene KOs. They also suggest that gene KOs identified with current DNA sequencing methodologies probably do not strongly influence normal variation in BMI, height, and WHR in the general human population. PMID:26908616

  9. Pressor responses to ephedrine are not impaired in dopamine β-hydroxylase knockout mice

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    Liles, J T; Baber, S R; Deng, W; Porter, J R; Corll, C; Murthy, S N; Thomas, S A; Kadowitz, P J

    2006-01-01

    Background and Purpose: Ephedrine and amphetamine can cause substantial increases in systemic arterial pressure. However, the role of endogenous noradrenaline release in mediating the pressor response to ephedrine is controversial. Studies using pharmacologic agents to decrease the synthesis, storage, and release of catecholamines have supported both a direct and an indirect mechanism of action for ephedrine. The purpose of the present study was to determine if endogenous noradrenaline release is required for cardiovascular responses to ephedrine and amphetamine using a genetic mouse model. Experimental Approach: Increases in systemic arterial pressure and heart rate in response to ephedrine and amphetamine were investigated and compared in dopamine β-hydroxylase knockout (Dbh -/-) mice that cannot synthesize noradrenaline. Dbh +/- littermates have normal noradrenaline and adrenaline tissue levels, and served as controls in all experiments. Key Results: In Dbh -/- mice the increases in systemic arterial pressure and heart rate in response to i.v. injections of ephedrine were not impaired whereas responses to amphetamine were markedly reduced, when compared with responses in Dbh +/- mice. The pressor response to tyramine was abolished whereas pressor responses to noradrenaline, phenylephrine, dopamine, and angiotensin II were similar in Dbh -/- and Dbh +/- mice. Conclusions and Implications: The present results in Dbh -/- mice provide support for the hypothesis that pressor responses to ephedrine are directly mediated whereas responses to amphetamine are dependent on the release of noradrenaline and suggest that Dbh +/- and Dbh -/- mice are useful for the study of direct and indirect mechanisms. PMID:17099719

  10. Pressor responses to ephedrine are not impaired in dopamine beta-hydroxylase knockout mice.

    Science.gov (United States)

    Liles, J T; Baber, S R; Deng, W; Porter, J R; Corll, C; Murthy, S N; Thomas, S A; Kadowitz, P J

    2007-01-01

    Ephedrine and amphetamine can cause substantial increases in systemic arterial pressure. However, the role of endogenous noradrenaline release in mediating the pressor response to ephedrine is controversial. Studies using pharmacologic agents to decrease the synthesis, storage, and release of catecholamines have supported both a direct and an indirect mechanism of action for ephedrine. The purpose of the present study was to determine if endogenous noradrenaline release is required for cardiovascular responses to ephedrine and amphetamine using a genetic mouse model. Increases in systemic arterial pressure and heart rate in response to ephedrine and amphetamine were investigated and compared in dopamine beta-hydroxylase knockout (Dbh -/-) mice that cannot synthesize noradrenaline. Dbh +/- littermates have normal noradrenaline and adrenaline tissue levels, and served as controls in all experiments. In Dbh -/- mice the increases in systemic arterial pressure and heart rate in response to i.v. injections of ephedrine were not impaired whereas responses to amphetamine were markedly reduced, when compared with responses in Dbh +/- mice. The pressor response to tyramine was abolished whereas pressor responses to noradrenaline, phenylephrine, dopamine, and angiotensin II were similar in Dbh -/- and Dbh +/- mice. The present results in Dbh -/- mice provide support for the hypothesis that pressor responses to ephedrine are directly mediated whereas responses to amphetamine are dependent on the release of noradrenaline and suggest that Dbh +/- and Dbh -/- mice are useful for the study of direct and indirect mechanisms.

  11. Soy milk versus simvastatin for preventing atherosclerosis and left ventricle remodeling in LDL receptor knockout mice.

    Science.gov (United States)

    Santos, L; Davel, A P; Almeida, T I R; Almeida, M R; Soares, E A; Fernandes, G J M; Magalhães, S F; Barauna, V G; Garcia, J A D

    2017-02-20

    Functional food intake has been highlighted as a strategy for the prevention of cardiovascular diseases by reducing risk factors. In this study, we compared the effects of oral treatment with soy milk and simvastatin on dyslipidemia, left ventricle remodeling and atherosclerotic lesion of LDL receptor knockout mice (LDLr-/-) fed a hyperlipidic diet. Forty 3-month old male LDLr-/- mice were distributed into four groups: control group (C), in which animals received standard diet; HL group, in which animals were fed a hyperlipidic diet; HL+SM or HL+S groups, in which animals were submitted to a hyperlipidic diet plus soy milk or simvastatin, respectively. After 60 days, both soy milk and simvastatin treatment prevented dyslipidemia, atherosclerotic lesion progression and left ventricle hypertrophy in LDLr-/- mice. These beneficial effects of soy milk and simvastatin were associated with reduced oxidative stress and inflammatory state in the heart and aorta caused by the hyperlipidic diet. Treatment with soy milk was more effective in preventing HDLc reduction and triacylglycerol and VLDLc increase. On the other hand, simvastatin was more effective in preventing an increase in total cholesterol, LDLc and superoxide production in aorta, as well as CD40L both in aorta and left ventricle of LDLr-/-. In conclusion, our results suggest a cardioprotective effect of soy milk in LDLr-/- mice comparable to the well-known effects of simvastatin.

  12. Diacylglycerol kinase β knockout mice exhibit lithium-sensitive behavioral abnormalities.

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    Kenichi Kakefuda

    Full Text Available BACKGROUND: Diacylglycerol kinase (DGK is an enzyme that phosphorylates diacylglycerol (DG to produce phosphatidic acid (PA. DGKβ is widely distributed in the central nervous system, such as the olfactory bulb, cerebral cortex, striatum, and hippocampus. Recent studies reported that the splice variant at the COOH-terminal of DGKβ was related to bipolar disorder, but its detailed mechanism is still unknown. METHODOLOGY/PRINCIPAL FINDINGS: In the present study, we performed behavioral tests using DGKβ knockout (KO mice to investigate the effects of DGKβ deficits on psychomotor behavior. DGKβ KO mice exhibited some behavioral abnormalities, such as hyperactivity, reduced anxiety, and reduced depression. Additionally, hyperactivity and reduced anxiety were attenuated by the administration of the mood stabilizer, lithium, but not haloperidol, diazepam, or imipramine. Moreover, DGKβ KO mice showed impairment in Akt-glycogen synthesis kinase (GSK 3β signaling and cortical spine formation. CONCLUSIONS/SIGNIFICANCE: These findings suggest that DGKβ KO mice exhibit lithium-sensitive behavioral abnormalities that are, at least in part, due to the impairment of Akt-GSK3β signaling and cortical spine formation.

  13. Cellular responses during morphological transformation in Azospirillum brasilense and Its flcA knockout mutant.

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    Xingsheng Hou

    Full Text Available FlcA is a response regulator controlling flocculation and the morphological transformation of Azospirillum cells from vegetative to cyst-like forms. To understand the cellular responses of Azospirillum to conditions that cause morphological transformation, proteins differentially expressed under flocculation conditions in A. brasilense Sp7 and its flcA knockout mutant were investigated. Comparison of 2-DE protein profiles of wild-type (Sp7 and a flcA deletion mutant (Sp7-flcAΔ revealed a total of 33 differentially expressed 2-DE gel spots, with 22 of these spots confidently separated to allow protein identification. Analysis of these spots by liquid chromatography-tandem mass spectrometry (LC-MS/MS and MASCOT database searching identified 48 proteins (≥10% emPAI in each spot. The functional characteristics of these proteins included carbon metabolism (beta-ketothiolase and citrate synthase, nitrogen metabolism (Glutamine synthetase and nitric oxide synthase, stress tolerance (superoxide dismutase, Alkyl hydroperoxidase and ATP-dependent Clp protease proteolytic subunit and morphological transformation (transducer coupling protein. The observed differences between Sp7 wild-type and flcA- strains enhance our understanding of the morphological transformation process and help to explain previous phenotypical observations. This work is a step forward in connecting the Azospirillum phenome and genome.

  14. Chemical Transport Knockout for Oxidized Vitamin C, Dehydroascorbic Acid, Reveals Its Functions in vivo

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    Hongbin Tu

    2017-09-01

    Full Text Available Despite its transport by glucose transporters (GLUTs in vitro, it is unknown whether dehydroascorbic acid (oxidized vitamin C, DHA has any in vivo function. To investigate, we created a chemical transport knockout model using the vitamin C analog 6-bromo-ascorbate. This analog is transported on sodium-dependent vitamin C transporters but its oxidized form, 6-bromo-dehydroascorbic acid, is not transported by GLUTs. Mice (gulo−/− unable to synthesize ascorbate (vitamin C were raised on 6-bromo-ascorbate. Despite normal survival, centrifugation of blood produced hemolysis secondary to near absence of red blood cell (RBC ascorbate/6-bromo-ascorbate. Key findings with clinical implications were that RBCs in vitro transported dehydroascorbic acid but not bromo-dehydroascorbic acid; RBC ascorbate in vivo was obtained only via DHA transport; ascorbate via DHA transport in vivo was necessary for RBC structural integrity; and internal RBC ascorbate was essential to maintain ascorbate plasma concentrations in vitro/in vivo.

  15. Cellular responses during morphological transformation in Azospirillum brasilense and Its flcA knockout mutant.

    Science.gov (United States)

    Hou, Xingsheng; McMillan, Mary; Coumans, Joëlle V F; Poljak, Anne; Raftery, Mark J; Pereg, Lily

    2014-01-01

    FlcA is a response regulator controlling flocculation and the morphological transformation of Azospirillum cells from vegetative to cyst-like forms. To understand the cellular responses of Azospirillum to conditions that cause morphological transformation, proteins differentially expressed under flocculation conditions in A. brasilense Sp7 and its flcA knockout mutant were investigated. Comparison of 2-DE protein profiles of wild-type (Sp7) and a flcA deletion mutant (Sp7-flcAΔ) revealed a total of 33 differentially expressed 2-DE gel spots, with 22 of these spots confidently separated to allow protein identification. Analysis of these spots by liquid chromatography-tandem mass spectrometry (LC-MS/MS) and MASCOT database searching identified 48 proteins (≥10% emPAI in each spot). The functional characteristics of these proteins included carbon metabolism (beta-ketothiolase and citrate synthase), nitrogen metabolism (Glutamine synthetase and nitric oxide synthase), stress tolerance (superoxide dismutase, Alkyl hydroperoxidase and ATP-dependent Clp protease proteolytic subunit) and morphological transformation (transducer coupling protein). The observed differences between Sp7 wild-type and flcA- strains enhance our understanding of the morphological transformation process and help to explain previous phenotypical observations. This work is a step forward in connecting the Azospirillum phenome and genome.

  16. Utilising the resources of the International Knockout Mouse Consortium: the Australian experience.

    Science.gov (United States)

    Cotton, Leanne M; Meilak, Michelle L; Templeton, Tanya; Gonzales, Jose G; Nenci, Arianna; Cooney, Melissa; Truman, Dirk; Rodda, Fleur; Lynas, Alyce; Viney, Elizabeth; Rosenthal, Nadia; Bianco, Deborah M; O'Bryan, Moira K; Smyth, Ian M

    2015-04-01

    Mouse models play a key role in the understanding gene function, human development and disease. In 2007, the Australian Government provided funding to establish the Monash University embryonic stem cell-to-mouse (ES2M) facility. This was part of the broader Australian Phenomics Network, a national infrastructure initiative aimed at maximising access to global resources for understanding gene function in the mouse. The remit of the ES2M facility is to provide subsidised access for Australian biomedical researchers to the ES cell resources available from the International Knockout Mouse Consortium (IKMC). The stated aim of the IKMC is to generate a genetically modified mouse ES cell line for all of the ~23,000 genes in the mouse genome. The principal function of the Monash University ES2M service is to import genetically modified ES cells into Australia and to convert them into live mice with the potential to study human disease. Through advantages of economy of scale and established relationships with ES cell repositories worldwide, we have created over 110 germline mouse strains sourced from all of the major ES providers worldwide. We comment on our experience in generating these mouse lines; providing a snapshot of a "clients" perspective of using the IKMC resource and one which we hope will serve as a guide to other institutions or organisations contemplating establishing a similar centralised service.

  17. Impairment in extinction of cued fear memory in syntenin-1 knockout mice.

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    Talukdar, Gourango; Inoue, Ran; Yoshida, Tomoyuki; Mori, Hisashi

    2018-03-01

    Syntenin-1 is a PDZ domain-containing intracellular scaffold protein involved in exosome production, synapse formation, and synaptic plasticity. We tested whether syntenin-1 can regulate learning and memory through its effects on synaptic plasticity. Specifically, we investigated the role of syntenin-1 in contextual and cued fear conditioning and extinction of conditioned fear using syntenin-1 knockout (KO) mice. Genetic disruption of syntenin-1 had little effect on contextual and cued fear memory. However, syntenin-1 KO mice exhibited selective impairment in cued fear extinction retention. This extinction retention deficit in syntenin-1 KO mice was associated with reduced c-Fos-positive neurons in the basolateral amygdala (BLA) and infralimbic cortex (IL) after extinction training and increased c-Fos-positive neurons in the BLA after an extinction retention test. Our results suggest that syntenin-1 plays an important role in extinction of cued fear memory by modulating neuronal activity in the BLA and IL. Copyright © 2018 Elsevier Inc. All rights reserved.

  18. Sexual dimorphism in the glucose homeostasis phenotype of the Aromatase Knockout (ArKO) mice.

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    Van Sinderen, Michelle; Steinberg, Gregory; Jorgensen, Sebastian B; Honeyman, Jane; Chow, Jenny D Y; Simpson, Evan R; Jones, Margaret E E; Boon, Wah Chin

    2017-06-01

    We investigated the effects of estrogens on glucose homeostasis using the Aromatase Knockout (ArKO) mouse, which is unable to convert androgens into estrogens. The ArKO mouse is a model of total estrogen ablation which develops symptoms of metabolic syndrome. To determine the development and progression of whole body state of insulin resistance of ArKO mice, comprehensive whole body tolerance tests were performed on WT, ArKO and estrogen administrated mice at 3 and 12 months of age. The absence of estrogens in the male ArKO mice leads to hepatic insulin resistance, glucose and pyruvate intolerance from 3 to 12 months with consistent improvement upon estrogen treatment. Estrogen absence in the female ArKO mice leads to glucose intolerance without pyruvate intolerance or insulin resistance. The replacement of estrogens in the female WT and ArKO mice exhibited both insulin sensitizing and resistance effects depending on age and dosage. In conclusion, this study presents information on the sexually dimorphic roles of estrogens on glucose homeostasis regulation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. [ADAR1 Knockout Inhibits Notch1-induced T-ALL in Mice].

    Science.gov (United States)

    Gao, Hui-Er; Peng, Lu-Yun; Yang, Xin; Zhang, Ying-Chi; Hu, Tian-Yuan; Xu, Jing; Yuan, Wei-Ping; Cheng, Tao; Gao, Ying-Dai

    2016-06-01

    To investigate the effect of ADAR1 on the occurrence and development of mouse T cell acute lymphoblastic leukemia (T-ALL). Lck-Cre; ADAR1lox/lox mice were generated through interbreeding. The lineage-cells of Lck-Cre; ADAR1lox/lox mice and the control were enriched respectively by the means of MACS, and the lin- cells were transfected with retrovirus carrying MSCV-ICN1-IRES-GFP fusion gene. Then the transfection efficiency was detected by the means of FACS, and the same number of GFP+ cells were transplanted into lethally irradiated recipient mice to observe the survival of mice in 2 recipient group after transplantation. T cell-specific knockout ADAR1 mice were generated, and Notch1-induced T-ALL mouse model was established successfully. The leukemia with T-ALL characteristics occured in the mice of control group, but did not in the ADAR1 kmockout mice after transplantation. ADAR1 plays a key role in the incidence and development of Notch1-induced T-ALL.

  20. Serum CTX levels and histomorphometric analysis in Src versus RANKL knockout mice.

    Science.gov (United States)

    Takeshita, Sunao; Fumoto, Toshio; Ito, Masako; Ikeda, Kyoji

    2017-06-06

    Src knockout (KO) and RANKL KO mice both exhibit near complete osteopetrosis in terms of 3D-bone volume (BV) fraction by micro-CT, whereas the serum CTX concentration of Src KO is apparently normal and that of RANKL KO is 30% of wild-type (WT) despite the fact that they lack osteoclasts. By histomorphometry we found that, whereas eroded surface (ES) and osteoid surface (OS) are zero values in RANKL KO, they are indistinguishable from WT in Src KO; because of marked increase in bone surface (BS), ES/BS and OS/BS of Src KO are 30-40% of WT. While RANKL KO lack both osteoclasts and osteoblasts, Src KO reveal increased numbers of osteoclasts and indistinguishable numbers of osteoblasts compared with WT; again, on the basis of BS, N.Oc/BS is comparable to WT and N.Ob/BS is markedly decreased in Src KO. The apparently increased number of total osteoclasts may be due to increased expression of RANKL found in Src KO bone in vivo. Src has a gene dosage-dependent effect on osteoclast function in vitro, with Src -/- osteoclasts completely lacking bone-resorbing function as determined by CTX release on dentin. Thus, Src KO osteoclasts retain some bone-resorbing function in vivo. The number of osteocytes is proportionally increased in RANKL KO, while Src KO mice have relative osteocyte deficiency, raising the possibility that RANKL and Src has an unrecognized role in osteocyte survival.

  1. MicroRNA-155 knockout mice are susceptible to Mycobacterium tuberculosis infection.

    Science.gov (United States)

    Iwai, Hiroki; Funatogawa, Keiji; Matsumura, Kazunori; Kato-Miyazawa, Masako; Kirikae, Fumiko; Kiga, Kotaro; Sasakawa, Chihiro; Miyoshi-Akiyama, Tohru; Kirikae, Teruo

    2015-05-01

    MicroRNAs (miRNAs) are short, conserved, non-coding RNA molecules that repress translation, followed by the decay of miRNA-targeted mRNAs that encode molecules involved in cell differentiation, development, immunity and apoptosis. At least six miRNAs, including microRNA-155 (miR-155), were up-regulated when born marrow-derived macrophages from C57BL/6 mice were infected with Mycobacterium tuberculosis Erdman. C57BL/6 mice intravenously infected with Erdman showed up-regulation of miR-155 in livers and lungs. Following infection, miR-155-deficient C57BL/6 mice died significantly earlier and had significantly higher numbers of CFU in lungs than wild-type mice. Moreover, fewer CD4(+) T cells, but higher numbers of monocytes and neutrophils, were present in the lungs of Erdman-infected miR-155 knockout (miR-155(-/-)) than of wild-type mice. These findings indicated that miR-155 plays a critical role in immune responses to M. tuberculosis. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Phosphocreatine kinetics at the onset of contractions in skeletal muscle of MM creatine kinase knockout mice

    Science.gov (United States)

    Roman, Brian B.; Meyer, Ronald A.; Wiseman, Robert W.

    2002-01-01

    Phosphocreatine (PCr) depletion during isometric twitch stimulation at 5 Hz was measured by (31)P-NMR spectroscopy in gastrocnemius muscles of pentobarbital-anesthetized MM creatine kinase knockout (MMKO) vs. wild-type C57B (WT) mice. PCr depletion after 2 s of stimulation, estimated from the difference between spectra gated to times 200 ms and 140 s after 2-s bursts of contractions, was 2.2 +/- 0.6% of initial PCr in MMKO muscle vs. 9.7 +/- 1.6% in WT muscles (mean +/- SE, n = 7, P ATP ratio and intracellular pH were not significantly different between groups, and there was no detectable change in intracellular pH or ATP in either group after 2 s. The initial difference in net PCr depletion was maintained during the first minute of continuous 5-Hz stimulation. However, there was no significant difference in the quasi-steady-state PCr level approached after 80 s (MMKO 36.1 +/- 3.5 vs. WT 35.5 +/- 4.4% of initial PCr; n = 5-6). A kinetic model of ATPase, creatine kinase, and adenylate kinase fluxes during stimulation was consistent with the observed PCr depletion in MMKO muscle after 2 s only if ADP-stimulated oxidative phosphorylation was included in the model. Taken together, the results suggest that cytoplasmic ADP more rapidly increases and oxidative phosphorylation is more rapidly activated at the onset of contractions in MMKO compared with WT muscles.

  3. Examination of MARCO activity on dendritic cell phenotype and function using a gene knockout mouse.

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    Hiroshi Komine

    Full Text Available We have reported the upregulation of MARCO, a member of the class A scavenger receptor family, on the surface of murine and human dendritic cells (DCs pulsed with tumor lysates. Exposure of murine tumor lysate-pulsed DCs to an anti-MARCO antibody led to loss of dendritic-like processes and enhanced migratory capacity. In this study, we have further examined the biological and therapeutic implications of MARCO expression by DCs. DCs generated from the bone marrow (bm of MARCO knockout (MARCO⁻/⁻ mice were phenotypically similar to DCs generated from the bm of wild-type mice and produced normal levels of IL-12 and TNF-α when exposed to LPS. MARCO⁻/⁻ DCs demonstrated enhanced migratory capacity in response to CCL-21 in vitro. After subcutaneous injection into mice, MARCO⁻/⁻ TP-DCs migrated more efficiently to the draining lymph node leading to enhanced generation of tumor-specific IFN-γ producing T cells and improved tumor regression and survival in B16 melanoma-bearing mice. These results support targeting MARCO on the surface of DCs to improve trafficking and induction of anti-tumor immunity.

  4. Effects of Three Lipidated Oxytocin Analogs on Behavioral Deficits in CD38 Knockout Mice

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    Stanislav M. Cherepanov

    2017-10-01

    Full Text Available Oxytocin (OT is a nonapeptide that plays an important role in social behavior. Nasal administration of OT has been shown to improve trust in healthy humans and social interaction in autistic subjects. As is consistent with the nature of a peptide, OT has some unfavorable characteristics: it has a short half-life in plasma and shows poor permeability across the blood-brain barrier. Analogs with long-lasting effects may overcome these drawbacks. To this end, we have synthesized three analogs: lipo-oxytocin-1 (LOT-1, in which two palmitoyl groups are conjugated to the cysteine and tyrosine residues, lipo-oxytocin-2 (LOT-2 and lipo-oxytocin-3 (LOT-3, which include one palmitoyl group conjugated at the cysteine or tyrosine residue, respectively. The following behavioral deficits were observed in CD38 knockout (CD38−/− mice: a lack of paternal nurturing in CD38−/− sires, decreased ability for social recognition, and decreased sucrose consumption. OT demonstrated the ability to recover these disturbances to the level of wild-type mice for 30 min after injection. LOT-2 and LOT-3 partially recovered the behaviors for a short period. Conversely, LOT-1 restored the behavioral parameters, not for 30 min, but for 24 h. These data suggest that the lipidation of OT has some therapeutic benefits, and LOT-1 would be most useful because of its long-last activity.

  5. Interactions of the opioid and cannabinoid systems in reward: Insights from knockout studies

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    Katia eBefort

    2015-02-01

    Full Text Available The opioid system consists of three receptors, mu, delta, and kappa, which are activated by endogenous opioid peptides (enkephalins, endorphins and dynorphins. The endogenous cannabinoid system comprises lipid neuromodulators (endocannabinoids, enzymes for their synthesis and their degradation and two well-characterized receptors, cannabinoid receptors CB1 and CB2. These systems play a major role in the control of pain as well as in mood regulation, reward processing and the development of addiction. Both opioid and cannabinoid receptors are coupled to G proteins and are expressed throughout the brain reinforcement circuitry. Extending classical pharmacology, research using genetically modified mice has provided important progress in the identification of the specific contribution of each component of these endogenous systems in vivo on reward process. This review will summarize available genetic tools and our present knowledge on the consequences of gene knockout on reinforced behaviors in both systems, with a focus on their potential interactions. A better understanding of opioid-cannabinoid interactions may provide novel strategies for therapies in addicted individuals.

  6. ChREBP-Knockout Mice Show Sucrose Intolerance and Fructose Malabsorption.

    Science.gov (United States)

    Kato, Takehiro; Iizuka, Katsumi; Takao, Ken; Horikawa, Yukio; Kitamura, Tadahiro; Takeda, Jun

    2018-03-12

    We have previously reported that 60% sucrose diet-fed ChREBP knockout mice (KO) showed body weight loss resulting in lethality. We aimed to elucidate whether sucrose and fructose metabolism are impaired in KO. Wild-type mice (WT) and KO were fed a diet containing 30% sucrose with/without 0.08% miglitol, an α-glucosidase inhibitor, and these effects on phenotypes were tested. Furthermore, we compared metabolic changes of oral and peritoneal fructose injection. A thirty percent sucrose diet feeding did not affect phenotypes in KO. However, miglitol induced lethality in 30% sucrose-fed KO. Thirty percent sucrose plus miglitol diet-fed KO showed increased cecal contents, increased fecal lactate contents, increased growth of lactobacillales and Bifidobacterium and decreased growth of clostridium cluster XIVa. ChREBP gene deletion suppressed the mRNA levels of sucrose and fructose related genes. Next, oral fructose injection did not affect plasma glucose levels and liver fructose contents; however, intestinal sucrose and fructose related mRNA levels were increased only in WT. In contrast, peritoneal fructose injection increased plasma glucose levels in both mice; however, the hepatic fructose content in KO was much higher owing to decreased hepatic Khk mRNA expression. Taken together, KO showed sucrose intolerance and fructose malabsorption owing to decreased gene expression.

  7. ChREBP-Knockout Mice Show Sucrose Intolerance and Fructose Malabsorption

    Directory of Open Access Journals (Sweden)

    Takehiro Kato

    2018-03-01

    Full Text Available We have previously reported that 60% sucrose diet-fed ChREBP knockout mice (KO showed body weight loss resulting in lethality. We aimed to elucidate whether sucrose and fructose metabolism are impaired in KO. Wild-type mice (WT and KO were fed a diet containing 30% sucrose with/without 0.08% miglitol, an α-glucosidase inhibitor, and these effects on phenotypes were tested. Furthermore, we compared metabolic changes of oral and peritoneal fructose injection. A thirty percent sucrose diet feeding did not affect phenotypes in KO. However, miglitol induced lethality in 30% sucrose-fed KO. Thirty percent sucrose plus miglitol diet-fed KO showed increased cecal contents, increased fecal lactate contents, increased growth of lactobacillales and Bifidobacterium and decreased growth of clostridium cluster XIVa. ChREBP gene deletion suppressed the mRNA levels of sucrose and fructose related genes. Next, oral fructose injection did not affect plasma glucose levels and liver fructose contents; however, intestinal sucrose and fructose related mRNA levels were increased only in WT. In contrast, peritoneal fructose injection increased plasma glucose levels in both mice; however, the hepatic fructose content in KO was much higher owing to decreased hepatic Khk mRNA expression. Taken together, KO showed sucrose intolerance and fructose malabsorption owing to decreased gene expression.

  8. Effects of Eaf2 gene knockout on cataract induced by ultraviolet irradiation in mice

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    Yan-Hua Jiang

    2016-02-01

    Full Text Available AIM:To evaluate the effects of Eaf2 gene knockout on cataract in mice induced by ultraviolet irradiation.METHODS:Fifteen wild type mice were used as the control group, and 10 Eaf2 KO mice were used as the experimental group. The 14-week mice were taken as the research objects in the two groups. So the subgroups were: WT -nonUV, WT -UV, Eaf2 KO-nonUV and Eaf2 KO-UV, a total of 4 groups. Observe the lens of mice in vivo with slit lamp microscope, grade the lens opacity with Lens Opacities Classification System II(LOCSII. Then the mice were sacrificed by breaking the neck, the lens were removed and were observed by dark field microscopy. According to the captured images, the proportion of cataract region was analyzed using Image J software. The data of the two groups were statistically analyzed.RESULTS: The results detected by the two methods were similar. In WT-UV group and Eaf2 KO-UV group, the degree of lens opacity was significantly higher than those of WT-nonUV group and Eaf2 KO-nonUV group. The lens opacity of WT-UV group was significantly higher than that in Eaf2 KO-UV group, and the difference was statistically significant(PCONCLUSION: Ultraviolet radiation can lead to the formation of cataract in mice. Eaf2 protein can promote the formation of cataract in mice caused by ultraviolet.

  9. Impaired functional organization in the visual cortex of muscarinic receptor knock-out mice.

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    Groleau, Marianne; Nguyen, Hoang Nam; Vanni, Matthieu P; Huppé-Gourgues, Frédéric; Casanova, Christian; Vaucher, Elvire

    2014-09-01

    Acetylcholine modulates maturation and neuronal activity through muscarinic and nicotinic receptors in the primary visual cortex. However, the specific contribution of different muscarinic receptor subtypes in these neuromodulatory mechanisms is not fully understood. The present study evaluates in vivo the functional organization and the properties of the visual cortex of different groups of muscarinic receptor knock-out (KO) mice. Optical imaging of intrinsic signals coupled to continuous and episodic visual stimulation paradigms was used. Retinotopic maps along elevation and azimuth were preserved among the different groups of mice. However, compared to their wild-type counterparts, the apparent visual field along elevation was larger in M2/M4-KO mice but smaller in M1-KO. There was a reduction in the estimated relative receptive field size of V1 neurons in M1/M3-KO and M1-KO mice. Spatial frequency and contrast selectivity of V1 neuronal populations were affected only in M1/M3-KO and M1-KO mice. Finally, the neuronal connectivity was altered by the absence of M2/M4 muscarinic receptors. All these effects suggest the distinct roles of different subtypes of muscarinic receptors in the intrinsic organization of V1 and a strong involvement of the muscarinic transmission in the detectability of visual stimuli. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. Tensor-based morphometry and stereology reveal brain pathology in the complexin1 knockout mouse.

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    Kielar, Catherine; Sawiak, Stephen J; Navarro Negredo, Paloma; Tse, Desmond H Y; Morton, A Jennifer

    2012-01-01

    Complexins (Cplxs) are small, soluble, regulatory proteins that bind reversibly to the SNARE complex and modulate synaptic vesicle release. Cplx1 knockout mice (Cplx1(-/-)) have the earliest known onset of ataxia seen in a mouse model, although hitherto no histopathology has been described in these mice. Nevertheless, the profound neurological phenotype displayed by Cplx1(-/-) mutants suggests that significant functional abnormalities must be present in these animals. In this study, MRI was used to automatically detect regions where structural differences were not obvious when using a traditional histological approach. Tensor-based morphometry of Cplx1(-/-) mouse brains showed selective volume loss from the thalamus and cerebellum. Stereological analysis of Cplx1(-/-) and Cplx1(+/+) mice brain slices confirmed the volume loss in the thalamus as well as loss in some lobules of the cerebellum. Finally, stereology was used to show that there was loss of cerebellar granule cells in Cplx1(-/-) mice when compared to Cplx1(+/+) animals. Our study is the first to describe pathological changes in Cplx1(-/-) mouse brain. We suggest that the ataxia in Cplx1(-/-) mice is likely to be due to pathological changes in both cerebellum and thalamus. Reduced levels of Cplx proteins have been reported in brains of patients with neurodegenerative diseases. Therefore, understanding the effects of Cplx depletion in brains from Cplx1(-/-) mice may also shed light on the mechanisms underlying pathophysiology in disorders in which loss of Cplx1 occurs.

  11. Tensor-based morphometry and stereology reveal brain pathology in the complexin1 knockout mouse.

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    Catherine Kielar

    Full Text Available Complexins (Cplxs are small, soluble, regulatory proteins that bind reversibly to the SNARE complex and modulate synaptic vesicle release. Cplx1 knockout mice (Cplx1(-/- have the earliest known onset of ataxia seen in a mouse model, although hitherto no histopathology has been described in these mice. Nevertheless, the profound neurological phenotype displayed by Cplx1(-/- mutants suggests that significant functional abnormalities must be present in these animals. In this study, MRI was used to automatically detect regions where structural differences were not obvious when using a traditional histological approach. Tensor-based morphometry of Cplx1(-/- mouse brains showed selective volume loss from the thalamus and cerebellum. Stereological analysis of Cplx1(-/- and Cplx1(+/+ mice brain slices confirmed the volume loss in the thalamus as well as loss in some lobules of the cerebellum. Finally, stereology was used to show that there was loss of cerebellar granule cells in Cplx1(-/- mice when compared to Cplx1(+/+ animals. Our study is the first to describe pathological changes in Cplx1(-/- mouse brain. We suggest that the ataxia in Cplx1(-/- mice is likely to be due to pathological changes in both cerebellum and thalamus. Reduced levels of Cplx proteins have been reported in brains of patients with neurodegenerative diseases. Therefore, understanding the effects of Cplx depletion in brains from Cplx1(-/- mice may also shed light on the mechanisms underlying pathophysiology in disorders in which loss of Cplx1 occurs.

  12. Single-neutron knockout from 20C and the structure of 19C

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    Hwang, J. W.; Kim, S.; Satou, Y.; Orr, N. A.; Kondo, Y.; Nakamura, T.; Gibelin, J.; Achouri, N. L.; Aumann, T.; Baba, H.; Delaunay, F.; Doornenbal, P.; Fukuda, N.; Inabe, N.; Isobe, T.; Kameda, D.; Kanno, D.; Kobayashi, N.; Kobayashi, T.; Kubo, T.; Leblond, S.; Lee, J.; Marqués, F. M.; Minakata, R.; Motobayashi, T.; Murai, D.; Murakami, T.; Muto, K.; Nakashima, T.; Nakatsuka, N.; Navin, A.; Nishi, S.; Ogoshi, S.; Otsu, H.; Sato, H.; Shimizu, Y.; Suzuki, H.; Takahashi, K.; Takeda, H.; Takeuchi, S.; Tanaka, R.; Togano, Y.; Tuff, A. G.; Vandebrouck, M.; Yoneda, K.

    2017-06-01

    The low-lying unbound level structure of the halo nucleus 19C has been investigated using single-neutron knockout from 20C on a carbon target at 280 MeV/nucleon. The invariant mass spectrum, derived from the momenta of the forward going beam velocity 18C fragment and neutrons, was found to be dominated by a very narrow near threshold (Erel = 0.036 (1) MeV) peak. Two less strongly populated resonance-like features were also observed at Erel = 0.84 (4) and 2.31 (3) MeV, both of which exhibit characteristics consistent with neutron p-shell hole states. Comparisons of the energies, measured cross sections and parallel momentum distributions to the results of shell-model and eikonal reaction calculations lead to spin-parity assignments of 5 /21+ and 1 /21- for the levels at Ex = 0.62 (9) and 2.89 (10) MeV with Sn = 0.58 (9) MeV. Spectroscopic factors were also deduced and found to be in reasonable accord with shell-model calculations. The valence neutron configuration of the 20C ground state is thus seen to include, in addition to the known 1s1/22 component, a significant 0d5/22 contribution. The level scheme of 19C, including significantly the 1 /21- cross-shell state, is well accounted for by the YSOX shell-model interaction developed from the monopole-based universal interaction.

  13. Age-Related Hearing Loss in Mn-SOD Heterozygous Knockout Mice

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    Makoto Kinoshita

    2013-01-01

    Full Text Available Age-related hearing loss (AHL reduces the quality of life for many elderly individuals. Manganese superoxide dismutase (Mn-SOD, one of the antioxidant enzymes acting within the mitochondria, plays a crucial role in scavenging reactive oxygen species (ROS. To determine whether reduction in Mn-SOD accelerates AHL, we evaluated auditory function in Mn-SOD heterozygous knockout (HET mice and their littermate wild-type (WT C57BL/6 mice by means of auditory brainstem response (ABR. Mean ABR thresholds were significantly increased at 16 months when compared to those at 4 months in both WT and HET mice, but they did not significantly differ between them at either age. The extent of hair cell loss, spiral ganglion cell density, and thickness of the stria vascularis also did not differ between WT and HET mice at either age. At 16 months, immunoreactivity of 8-hydroxydeoxyguanosine was significantly greater in the SGC and SV in HET mice compared to WT mice, but that of 4-hydroxynonenal did not differ between them. These findings suggest that, although decrease of Mn-SOD by half may increase oxidative stress in the cochlea to some extent, it may not be sufficient to accelerate age-related cochlear damage under physiological aging process.

  14. Comprehensive reanalysis of transcription factor knockout expression data in Saccharomyces cerevisiae reveals many new targets.

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    Reimand, Jüri; Vaquerizas, Juan M; Todd, Annabel E; Vilo, Jaak; Luscombe, Nicholas M

    2010-08-01

    Transcription factor (TF) perturbation experiments give valuable insights into gene regulation. Genome-scale evidence from microarray measurements may be used to identify regulatory interactions between TFs and targets. Recently, Hu and colleagues published a comprehensive study covering 269 TF knockout mutants for the yeast Saccharomyces cerevisiae. However, the information that can be extracted from this valuable dataset is limited by the method employed to process the microarray data. Here, we present a reanalysis of the original data using improved statistical techniques freely available from the BioConductor project. We identify over 100,000 differentially expressed genes-nine times the total reported by Hu et al. We validate the biological significance of these genes by assessing their functions, the occurrence of upstream TF-binding sites, and the prevalence of protein-protein interactions. The reanalysed dataset outperforms the original across all measures, indicating that we have uncovered a vastly expanded list of relevant targets. In summary, this work presents a high-quality reanalysis that maximizes the information contained in the Hu et al. compendium. The dataset is available from ArrayExpress (accession: E-MTAB-109) and it will be invaluable to any scientist interested in the yeast transcriptional regulatory system.

  15. Age-Dependent Defects of Regulatory B Cells in Wiskott-Aldrich Syndrome Gene Knockout Mice.

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    Tadafumi Yokoyama

    Full Text Available The Wiskott-Aldrich syndrome (WAS is a rare X-linked primary immunodeficiency characterized by recurrent infections, thrombocytopenia, eczema, and high incidence of malignancy and autoimmunity. The cellular mechanisms underlying autoimmune complications in WAS have been extensively studied; however, they remain incompletely defined. We investigated the characteristics of IL-10-producing CD19+CD1dhighCD5+ B cells (CD1dhighCD5+ Breg obtained from Was gene knockout (WKO mice and found that their numbers were significantly lower in these mice compared to wild type (WT controls. Moreover, we found a significant age-dependent reduction of the percentage of IL-10-expressing cells in WKO CD1dhighCD5+ Breg cells as compared to age-matched WT control mice. CD1dhighCD5+ Breg cells from older WKO mice did not suppress the in vitro production of inflammatory cytokines from activated CD4+ T cells. Interestingly, CD1dhighCD5+ Breg cells from older WKO mice displayed a basal activated phenotype which may prevent normal cellular responses, among which is the expression of IL-10. These defects may contribute to the susceptibility to autoimmunity with age in patients with WAS.

  16. Metabolism and tissue distribution of sulforaphane in Nrf2 knockout and wild-type mice.

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    Clarke, John D; Hsu, Anna; Williams, David E; Dashwood, Roderick H; Stevens, Jan F; Yamamoto, Masayuki; Ho, Emily

    2011-12-01

    To determine the metabolism and tissue distribution of the dietary chemoprotective agent sulforaphane following oral administration to wild-type and Nrf2 knockout (Nrf2(-/-)) mice. Male and female wild-type and Nrf2(-/-) mice were given sulforaphane (5 or 20 μmoles) by oral gavage; plasma, liver, kidney, small intestine, colon, lung, brain and prostate were collected at 2, 6 and 24 h (h). The five major metabolites of sulforaphane were measured in tissues by high performance liquid chromatography coupled with tandem mass spectrometry. Sulforaphane metabolites were detected in all tissues at 2 and 6 h post gavage, with the highest concentrations in the small intestine, prostate, kidney and lung. A dose-dependent increase in sulforaphane concentrations was observed in all tissues except prostate. At 5 μmole, Nrf2(-/-) genotype had no effect on sulforaphane metabolism. Only Nrf2(-/-) females given 20 μmoles sulforaphane for 6 h exhibited a marked increase in tissue sulforaphane metabolite concentrations. The relative abundance of each metabolite was not strikingly different between genders and genotypes. Sulforaphane is metabolized and reaches target tissues in wild-type and Nrf2(-/-) mice. These data provide further evidence that sulforaphane is bioavailable and may be an effective dietary chemoprevention agent for several tissue sites.

  17. Comprehensive behavioral analysis of calcium/calmodulin-dependent protein kinase IV knockout mice.

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    Keizo Takao

    Full Text Available Calcium-calmodulin dependent protein kinase IV (CaMKIV is a protein kinase that activates the transcription factor CREB, the cyclic AMP-response element binding protein. CREB is a key transcription factor in synaptic plasticity and memory consolidation. To elucidate the behavioral effects of CaMKIV deficiency, we subjected CaMKIV knockout (CaMKIV KO mice to a battery of behavioral tests. CaMKIV KO had no significant effects on locomotor activity, motor coordination, social interaction, pain sensitivity, prepulse inhibition, attention, or depression-like behavior. Consistent with previous reports, CaMKIV KO mice exhibited impaired retention in a fear conditioning test 28 days after training. In contrast, however, CaMKIV KO mice did not show any testing performance deficits in passive avoidance, one of the most commonly used fear memory paradigms, 28 days after training, suggesting that remote fear memory is intact. CaMKIV KO mice exhibited intact spatial reference memory learning in the Barnes circular maze, and normal spatial working memory in an eight-arm radial maze. CaMKIV KO mice also showed mildly decreased anxiety-like behavior, suggesting that CaMKIV is involved in regulating emotional behavior. These findings indicate that CaMKIV might not be essential for fear memory or spatial memory, although it is possible that the activities of other neural mechanisms or signaling pathways compensate for the CaMKIV deficiency.

  18. alpha7 Nicotinic acetylcholine receptor knockout selectively enhances ethanol-, but not beta-amyloid-induced neurotoxicity.

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    de Fiebre, Nancyellen C; de Fiebre, Christopher M

    2005-01-03

    The alpha7 subtype of nicotinic acetylcholine receptor (nAChR) has been implicated as a potential site of action for two neurotoxins, ethanol and the Alzheimer's disease related peptide, beta-amyloid. Here, we utilized primary neuronal cultures of cerebral cortex from alpha7 nAChR null mutant mice to examine the role of this receptor in modulating the neurotoxic properties of subchronic, "binge" ethanol and beta-amyloid. Knockout of the alpha7 nAChR gene selectively enhanced ethanol-induced neurotoxicity in a gene dosage-related fashion. Susceptibility of cultures to beta-amyloid induced toxicity, however, was unaffected by alpha7 nAChR gene null mutation. Further, beta-amyloid did not inhibit the binding of the highly alpha7-selective radioligand, [(125)I]alpha-bungarotoxin. On the other hand, in studies in Xenopus oocytes ethanol efficaciously inhibited alpha7 nAChR function. These data suggest that alpha7 nAChRs modulate the neurotoxic effects of binge ethanol, but not the neurotoxicity produced by beta-amyloid. It is hypothesized that inhibition of alpha7 nAChRs by ethanol provides partial protection against the neurotoxic properties of subchronic ethanol.

  19. Conditional Knockout of Telomerase Reverse Transcriptase in Mesenchymal Cells Impairs Mouse Pulmonary Fibrosis.

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    Tianju Liu

    Full Text Available Telomerase is typically expressed in cellular populations capable of extended replication, such as germ cells, tumor cells, and stem cells, but is also induced in tissue injury, repair and fibrosis. Its catalytic component, telomerase reverse transcriptase (TERT is induced in lung fibroblasts from patients with fibrotic interstitial lung disease and in rodents with bleomycin-induced pulmonary fibrosis. To evaluate the fibroblast specific role of TERT in pulmonary fibrosis, transgenic mice bearing a floxed TERT allele were generated, and then crossed with an inducible collagen α2(I-Cre mouse line to generate fibroblast specific TERT conditional knockout mice. TERT-specific deficiency in mesenchymal cells caused attenuation of pulmonary fibrosis as manifested by reduced lung hydroxyproline content, type I collagen and α-smooth muscle actin mRNA levels. The TERT-deficient mouse lung fibroblasts displayed decreased cell proliferative capacity and higher susceptibility to induced apoptosis compared with control cells. Additionally TERT deficiency was associated with heightened α-smooth muscle actin expression indicative of myofibroblast differentiation. However the impairment of cell proliferation and increased susceptibility to apoptosis would cause a reduction in the myofibroblast progenitor population necessary to mount a successful myofibroblast-dependent fibrotic response. These findings identified a key role for TERT in fibroblast proliferation and survival essential for pulmonary fibrosis.

  20. Bacterial and Pneumocystis Infections in the Lungs of Gene-Knockout Rabbits with Severe Combined Immunodeficiency

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    Jun Song

    2018-03-01

    Full Text Available Using the CRISPR/Cas9 gene-editing technology, we recently produced a number of rabbits with mutations in immune function genes, including FOXN1, PRKDC, RAG1, RAG2, and IL2RG. Seven founder knockout rabbits (F0 and three male IL2RG null (−/y F1 animals demonstrated severe combined immunodeficiency (SCID, characterized by absence or pronounced hypoplasia of the thymus and splenic white pulp, and absence of immature and mature T and B-lymphocytes in peripheral blood. Complete blood count analysis showed severe leukopenia and lymphocytopenia accompanied by severe neutrophilia. Without prophylactic antibiotics, the SCID rabbits universally succumbed to lung infections following weaning. Pathology examination revealed severe heterophilic bronchopneumonia caused by Bordetella bronchiseptica in several animals, but a consistent feature of lung lesions in all animals was a severe interstitial pneumonia caused by Pneumocystis oryctolagi, as confirmed by histological examination and PCR analysis of Pneumocystis genes. The results of this study suggest that these SCID rabbits could serve as a useful model for human SCID to investigate the disease pathogenesis and the development of gene and drug therapies.