WorldWideScience

Sample records for gene knockout studies

  1. Xenobiotic transporters: ascribing function from gene knockout and mutation studies.

    Science.gov (United States)

    Klaassen, Curtis D; Lu, Hong

    2008-02-01

    Transporter-mediated absorption, secretion, and reabsorption of chemicals are increasingly recognized as important determinants in the biological activities of many xenobiotics. In recent years, the rapid progress in generating and characterizing mice with targeted deletion of transporters has greatly increased our knowledge of the functions of transporters in the pharmacokinetics/toxicokinetics of xenobiotics. In this introduction, we focus on functions of transporters learned from experiments on knockout mice as well as humans and rodents with natural mutations of these transporters. We limit our discussion to transporters that either directly transport xenobiotics or are important in biliary excretion or cellular defenses, namely multidrug resistance, multidrug resistance-associated proteins, breast cancer resistance protein, organic anion transporting polypeptides, organic anion transporters, organic cation transporters, nucleoside transporters, peptide transporters, bile acid transporters, cholesterol transporters, and phospholipid transporters, as well as metal transporters. Efflux transporters in intestine, liver, kidney, brain, testes, and placenta can efflux xenobiotics out of cells and serve as barriers against the entrance of xenobiotics into cells, whereas many xenobiotics enter the biological system via uptake transporters. The functional importance of a given transporter in each tissue depends on its substrate specificity, expression level, and the presence/absence of other transporters with overlapping substrate preferences. Nevertheless, a transporter may affect a tissue independent of its local expression by altering systemic metabolism. Further studies on the gene regulation and function of transporters, as well as the interrelationship between transporters and phase I/II xenobiotic-metabolizing enzymes, will provide a complete framework for developing novel strategies to protect us from xenobiotic insults.

  2. Generating Targeted Gene Knockout Lines in Physcomitrella patens to Study Evolution of Stress-Responsive Mechanisms

    Science.gov (United States)

    Maronova, Monika; Kalyna, Maria

    2016-01-01

    The moss Physcomitrella patens possesses highly efficient homologous recombination allowing targeted gene manipulations and displays many features of the early land plants including high tolerance to abiotic stresses. It is therefore an invaluable model organism for studies of gene functions and comparative studies of evolution of stress responses in plants. Here, we describe a method for generating targeted gene knockout lines in P. patens using a polyethylene glycol-mediated transformation of protoplasts including basic in vitro growth, propagation, and maintenance techniques. PMID:26867627

  3. 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.

  4. Targeted gene knockout in chickens mediated by TALENs

    OpenAIRE

    Park, Tae Sub; Lee, Hong Jo; Kim, Ki Hyun; Kim, Jin-Soo; Han, Jae Yong

    2014-01-01

    Targeted gene knockout by editing specific loci in genome has revolutionized the field of functional genomics. Transcription activator-like effector nucleases (TALENs) are representative next-generation platforms for customized genomic editing in transgenic animals, as well as cultured cells in vitro. In this study, in combination with chicken primordial germ cell line with germ-line transmission capacity, we generated the ovalbumin gene knockout chickens by TALEN-mediated gene targeting. Our...

  5. Resources for methylome analysis suitable for gene knockout studies of potential epigenome modifiers

    Directory of Open Access Journals (Sweden)

    Wilson Gareth A

    2012-07-01

    Full Text Available Abstract Background Methylated DNA immunoprecipitation (MeDIP is a popular enrichment based method and can be combined with sequencing (termed MeDIP-seq to interrogate the methylation status of cytosines across entire genomes. However, quality control and analysis of MeDIP-seq data have remained to be a challenge. Results We report genome-wide DNA methylation profiles of wild type (wt and mutant mouse cells, comprising 3 biological replicates of Thymine DNA glycosylase (Tdg knockout (KO embryonic stem cells (ESCs, in vitro differentiated neural precursor cells (NPCs and embryonic fibroblasts (MEFs. The resulting 18 methylomes were analysed with MeDUSA (Methylated DNA Utility for Sequence Analysis, a novel MeDIP-seq computational analysis pipeline for the identification of differentially methylated regions (DMRs. The observed increase of hypermethylation in MEF promoter-associated CpG islands supports a previously proposed role for Tdg in the protection of regulatory regions from epigenetic silencing. Further analysis of genes and regions associated with the DMRs by gene ontology, pathway, and ChIP analyses revealed further insights into Tdg function, including an association of TDG with low-methylated distal regulatory regions. Conclusions We demonstrate that MeDUSA is able to detect both large-scale changes between cells from different stages of differentiation and also small but significant changes between the methylomes of cells that only differ in the KO of a single gene. These changes were validated utilising publicly available datasets and confirm TDG's function in the protection of regulatory regions from epigenetic silencing.

  6. [Roles of histamine receptors in pain perception: a study using receptors gene knockout mice].

    Science.gov (United States)

    Yanai, Kazuhiko; Mobarakeh, Jalal Izadi; Kuramasu, Atsuo; Sakurada, Shinobu

    2003-11-01

    To study the participation of histamine H1- and H2-receptors in pain perception, H1 and H2 receptor knockout (KO) mice were examined for pain threshold by means of three kinds of nociceptive tasks. These included assays for thermal, mechanical, and chemical nociception. H1KO mice showed significantly fewer nociceptive responses to the hot-plate, tail-flick, tail-pressure, paw-withdrawal, formalin, capsaicin, and abdominal constriction tests. Sensitivity to noxious stimuli in H1KO mice was significantly decreased when compared to wild-type mice. The antinociceptive phenotypes of H2KO were relatively less prominent when compared to H1KO mice. We also examined the antinociceptive effects of intrathecally-, intracerebroventricularly-, and subcutaneously-administered morphine in H1KO and H2KO mice. In these nociceptive assays, the antinociceptive effects produced by morphine were more enhanced in both H1KO and H2KO mice. The effects of histamine H1- and H2-receptor antagonists on morphine-induced antinociception were studied in ICR mice. The intrathecal, intracerebroventricular and subcutaneous co-administrations of d-chlorpheniramine enhanced the effects of morphine in all nociceptive assays examined. In addition, intrathecal co-administrations of cimetidine enhanced the antinociception of morphine in the hot plate tests. These results suggest that existing H1 and H2 receptors play an inhibitory role in morphine-induced antinociception in the spinal and supra-spinal levels.

  7. The role of nuclear factor E2-Related factor 2 and uncoupling protein 2 in glutathione metabolism: Evidence from an in vivo gene knockout study

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Yanyan [The First Affiliated Hospital, China Medical University, Shenyang, Liaoning (China); The Hamner Institutes for Health Sciences, Research Triangle Park, NC (United States); Xu, Yuanyuan, E-mail: yyxu@cmu.edu.cn [School of Public Health, China Medical University, Shenyang, Liaoning (China); Zheng, Hongzhi [The First Affiliated Hospital, China Medical University, Shenyang, Liaoning (China); The Hamner Institutes for Health Sciences, Research Triangle Park, NC (United States); Fu, Jingqi; Hou, Yongyong; Wang, Huihui [School of Public Health, China Medical University, Shenyang, Liaoning (China); Zhang, Qiang [Rollins School of Public Health, Emory University, Atlanta, GA (United States); Yamamoto, Masayuki [Graduate School of Medicine, Tohoku University, Sendai (Japan); Pi, Jingbo, E-mail: jbpi@cmu.edu.cn [School of Public Health, China Medical University, Shenyang, Liaoning (China); The Hamner Institutes for Health Sciences, Research Triangle Park, NC (United States)

    2016-09-09

    Nuclear factor E2-related factor 2 (NRF2) and uncoupling protein 2 (UCP2) are indicated to protect from oxidative stress. They also play roles in the homeostasis of glutathione. However, the detailed mechanisms are not well understood. In the present study, we found Nrf2-knockout (Nrf2-KO) mice exhibited altered glutathione homeostasis and reduced expression of various genes involved in GSH biosynthesis, regeneration, utilization and transport in the liver. Ucp2-knockout (Ucp2-KO) mice exhibited altered glutathione homeostasis in the liver, spleen and blood, as well as increased transcript of cystic fibrosis transmembrane conductance regulator in the liver, a protein capable of mediating glutathione efflux. Nrf2-Ucp2-double knockout (DKO) mice showed characteristics of both Nrf2-KO and Ucp2-KO mice. But no significant difference was observed in DKO mice when compared with Nrf2-KO or Ucp2-KO mice, except in blood glutathione levels. These data suggest that ablation of Nrf2 and Ucp2 leads to disrupted GSH balance, which could result from altered expression of genes involved in GSH metabolism. DKO may not evoke more severe oxidative stress than the single gene knockout. - Highlights: • Nrf2/Ucp2 deficiency leads to alteration of glutathione homeostasis. • Nrf2 regulates expression of genes in glutathione generation and utilization. • Ucp2 affects glutathione metabolism by regulating hepatic efflux of glutathione. • Nrf2 deficiency may not aggravate oxidative stress in Ucp2-deficient mice.

  8. A large-scale zebrafish gene knockout resource for the genome-wide study of gene function.

    Science.gov (United States)

    Varshney, Gaurav K; Lu, Jing; Gildea, Derek E; Huang, Haigen; Pei, Wuhong; Yang, Zhongan; Huang, Sunny C; Schoenfeld, David; Pho, Nam H; Casero, David; Hirase, Takashi; Mosbrook-Davis, Deborah; Zhang, Suiyuan; Jao, Li-En; Zhang, Bo; Woods, Ian G; Zimmerman, Steven; Schier, Alexander F; Wolfsberg, Tyra G; Pellegrini, Matteo; Burgess, Shawn M; Lin, Shuo

    2013-04-01

    With the completion of the zebrafish genome sequencing project, it becomes possible to analyze the function of zebrafish genes in a systematic way. The first step in such an analysis is to inactivate each protein-coding gene by targeted or random mutation. Here we describe a streamlined pipeline using proviral insertions coupled with high-throughput sequencing and mapping technologies to widely mutagenize genes in the zebrafish genome. We also report the first 6144 mutagenized and archived F1's predicted to carry up to 3776 mutations in annotated genes. Using in vitro fertilization, we have rescued and characterized ~0.5% of the predicted mutations, showing mutation efficacy and a variety of phenotypes relevant to both developmental processes and human genetic diseases. Mutagenized fish lines are being made freely available to the public through the Zebrafish International Resource Center. These fish lines establish an important milestone for zebrafish genetics research and should greatly facilitate systematic functional studies of the vertebrate genome.

  9. A large-scale zebrafish gene knockout resource for the genome-wide study of gene function

    Science.gov (United States)

    Varshney, Gaurav K.; Lu, Jing; Gildea, Derek E.; Huang, Haigen; Pei, Wuhong; Yang, Zhongan; Huang, Sunny C.; Schoenfeld, David; Pho, Nam H.; Casero, David; Hirase, Takashi; Mosbrook-Davis, Deborah; Zhang, Suiyuan; Jao, Li-En; Zhang, Bo; Woods, Ian G.; Zimmerman, Steven; Schier, Alexander F.; Wolfsberg, Tyra G.; Pellegrini, Matteo; Burgess, Shawn M.; Lin, Shuo

    2013-01-01

    With the completion of the zebrafish genome sequencing project, it becomes possible to analyze the function of zebrafish genes in a systematic way. The first step in such an analysis is to inactivate each protein-coding gene by targeted or random mutation. Here we describe a streamlined pipeline using proviral insertions coupled with high-throughput sequencing and mapping technologies to widely mutagenize genes in the zebrafish genome. We also report the first 6144 mutagenized and archived F1's predicted to carry up to 3776 mutations in annotated genes. Using in vitro fertilization, we have rescued and characterized ∼0.5% of the predicted mutations, showing mutation efficacy and a variety of phenotypes relevant to both developmental processes and human genetic diseases. Mutagenized fish lines are being made freely available to the public through the Zebrafish International Resource Center. These fish lines establish an important milestone for zebrafish genetics research and should greatly facilitate systematic functional studies of the vertebrate genome. PMID:23382537

  10. Behaviour Study of The Ras-GRF1 Gene knockout Mice%Ras-GRF1基因敲除小鼠的行为学研究

    Institute of Scientific and Technical Information of China (English)

    段巍鹤; 郑宏亮; 陆美林; 万家余; 何秀霞

    2015-01-01

    The Ras genes widely exist in nature, Ras-GRF1 proteins in cell signal transduction, cell differentiation and growth play a very important role. Previous researchs have shown that the Ras genes are closely associated with signal-ing pathways and learning and memory function. This research was study to companed the differences between the gene knockout Ras-GRF1 and will rats on learning and memory by the behavior experiments. It was found that Ras-GRF1 knockout mice learning memory ability weak in wild type mice by Morris water maze,etc.%Ras基因广泛存在于自然界中,其控制的Ras-GRF1蛋白在细胞信号传导,在细胞分化与生长过程中起着极其重要的作用。已有研究表明,Ras基因与信号通路和学习记忆功能密切相关。本实验利用行为学研究敲除Ras-GRF1基因的小鼠在学习记忆上与野生老鼠的差异,通过Morris水迷宫等实验发现Ras-GRF1基因敲除小鼠的学习记忆能力弱于野生型小鼠。

  11. The mammalian gene function resource: The International Knockout Mouse Consortium

    NARCIS (Netherlands)

    A. Bradley (Allan); K. Anastassiadis (Konstantinos); A. Ayadi (Abdelkader); J.F. Battey (James); C. Bell (Cindy); M.-C. Birling (Marie-Christine); J. Bottomley (Joanna); S.D.M. Brown (Steve); F. Bürger (Friederike); C.J. Bult (Carol); W. Bushell (Wendy); F.S. Collins (Francis); C. Desaintes (Christian); B. Doe (Brendan); E. Aris (Economides); J.T. Eppig (Janan); R.H. Finnell (Richard); C. Fletcher (Colin); M. Fray (Martin); D. Frendewey (David); R.H. Friedel (Roland); F.G. Grosveld (Frank); J. Hansen; Y. Hérault (Yann); G. Hicks (Geoffrey); A. Hörlein (Andreas); C. Houghton (Catherine); M. Hrabé De Angelis (Martin); D. Huylebroeck (Danny); V. Iyer (Vivek); P.J. de Jong (Pieter); J.A. Kadin (James); C. Kaloff (Cornelia); K. Kennedy (Karen); M. Koutsourakis (Manousos); K.C. Kent Lloyd (K.); S. Marschall (Susan); J. Mason (Jeremy); C. McKerlie (Colin); M.P. McLeod (Michael); H. von Melchner (Harald); M. Moore (Matt); A.O. Mujica (Alejandro); A. Nagy (Andras); M. Nefedov (Mikhail); L.M. Nutter (Lauryl); G. Pavlovic (Guillaume); J.L. Peterson (Jane); I. Pollock; R. Ramirez-Solis (Ramiro); D.E. Rancourt (Derrick); M. Raspa (Marcello); J.E. Remacle (Jacques); M. Ringwald (Martin); B. Rosen (Barry); N. Rosenthal (Nadia); J. Rossant (Janet); P. Ruiz Noppinger (Patricia); S. Ryder; J.Z. Schick (Joel Zupicich); F. Schnütgen (Frank); C.J. Schofield (Christopher); C. Seisenberger (Claudia); M. Selloum (Mohammed); E.M. Simpson (Elizabeth); W.C. Skarnes (William); D. Smedley (Damian); W.L. Stanford (William); A. Francis Stewart (A.); K. Stone (Kevin); K. Swan (Kate); H. Tadepally (Hamsa); J.L. Teboul (Jean Louis); G.P. Tocchini-Valentini (Glauco); D. Valenzuela (David); A.P. West (Anthony); K.-I. Yamamura (Ken-Ichi); Y. Yoshinaga (Yuko); M. Wurst (Martin)

    2012-01-01

    textabstractIn 2007, the International Knockout Mouse Consortium (IKMC) made the ambitious promise to generate mutations in virtually every protein-coding gene of the mouse genome in a concerted worldwide action. Now, 5 years later, the IKMC members have developed highthroughput gene trapping and, i

  12. The mammalian gene function resource: The International Knockout Mouse Consortium

    NARCIS (Netherlands)

    A. Bradley (Allan); K. Anastassiadis (Konstantinos); A. Ayadi (Abdelkader); J.F. Battey (James); C. Bell (Cindy); M.-C. Birling (Marie-Christine); J. Bottomley (Joanna); S.D.M. Brown (Steve); F. Bürger (Friederike); C.J. Bult (Carol); W. Bushell (Wendy); F.S. Collins (Francis); C. Desaintes (Christian); B. Doe (Brendan); E. Aris (Economides); J.T. Eppig (Janan); R.H. Finnell (Richard); C. Fletcher (Colin); M. Fray (Martin); D. Frendewey (David); R.H. Friedel (Roland); F.G. Grosveld (Frank); J. Hansen; Y. Hérault (Yann); G. Hicks (Geoffrey); A. Hörlein (Andreas); C. Houghton (Catherine); M. Hrabé De Angelis (Martin); D. Huylebroeck (Danny); V. Iyer (Vivek); P.J. de Jong (Pieter); J.A. Kadin (James); C. Kaloff (Cornelia); K. Kennedy (Karen); M. Koutsourakis (Manousos); K.C. Kent Lloyd (K.); S. Marschall (Susan); J. Mason (Jeremy); C. McKerlie (Colin); M.P. McLeod (Michael); H. von Melchner (Harald); M. Moore (Matt); A.O. Mujica (Alejandro); A. Nagy (Andras); M. Nefedov (Mikhail); L.M. Nutter (Lauryl); G. Pavlovic (Guillaume); J.L. Peterson (Jane); I. Pollock; R. Ramirez-Solis (Ramiro); D.E. Rancourt (Derrick); M. Raspa (Marcello); J.E. Remacle (Jacques); M. Ringwald (Martin); B. Rosen (Barry); N. Rosenthal (Nadia); J. Rossant (Janet); P. Ruiz Noppinger (Patricia); S. Ryder; J.Z. Schick (Joel Zupicich); F. Schnütgen (Frank); C.J. Schofield (Christopher); C. Seisenberger (Claudia); M. Selloum (Mohammed); E.M. Simpson (Elizabeth); W.C. Skarnes (William); D. Smedley (Damian); W.L. Stanford (William); A. Francis Stewart (A.); K. Stone (Kevin); K. Swan (Kate); H. Tadepally (Hamsa); J.L. Teboul (Jean Louis); G.P. Tocchini-Valentini (Glauco); D. Valenzuela (David); A.P. West (Anthony); K.-I. Yamamura (Ken-Ichi); Y. Yoshinaga (Yuko); M. Wurst (Martin)

    2012-01-01

    textabstractIn 2007, the International Knockout Mouse Consortium (IKMC) made the ambitious promise to generate mutations in virtually every protein-coding gene of the mouse genome in a concerted worldwide action. Now, 5 years later, the IKMC members have developed highthroughput gene trapping and,

  13. The biology of novel animal genes: Mouse APEX gene knockout

    Energy Technology Data Exchange (ETDEWEB)

    MacInnes, M.; Altherr, M.R.; Ludwig, D. [Los Alamos National Lab., NM (United States); Pedersen, R.; Mold, C. [Univ. of California, San Francisco, CA (United States)

    1997-07-01

    This is the final report of a one-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The controlled breeding of novel genes into mice, including the gene knockout (KO), or conversely by adding back transgenes provide powerful genetic technologies that together suffice to determine in large part the biological role(s) of novel genes. Inbred mouse remains the best understood and most useful mammalian experimental system available for tackling the biology of novel genes. The major mammalian apurinic/apyrimidinic (AP) endonuclease (APE), is involved in a key step in the repair of spontaneous and induced AP sites in DNA. Efficient repair of these lesions is imperative to prevent the stable incorporation of mutations into the cellular genome which may lead to cell death or transformation. Loss or modulation of base excison repair activity in vivo may elevate the spontaneous mutation rate in cells, and may lead to a substantial increase in the incidence of cancer. Despite extensive biochemical analysis, however, the significance of these individual APE functions in vivo has not been elucidated. Mouse embryonic stem (ES) cells heterozygous for a deletion mutation in APE have been generated and whole animals containing the APE mutation have been derived from these ES cells. Animals homozygous for the APE null mutation die early in gestation, underscoring the biological significance of this DNA repair gene.

  14. Generation of hypoxanthine phosphoribosyltransferase gene knockout rabbits by homologous recombination and gene trapping through somatic cell nuclear transfer.

    Science.gov (United States)

    Yin, Mingru; Jiang, Weihua; Fang, Zhenfu; Kong, Pengcheng; Xing, Fengying; Li, Yao; Chen, Xuejin; Li, Shangang

    2015-11-02

    The rabbit is a common animal model that has been employed in studies on various human disorders, and the generation of genetically modified rabbit lines is highly desirable. Female rabbits have been successfully cloned from cumulus cells, and the somatic cell nuclear transfer (SCNT) technology is well established. The present study generated hypoxanthine phosphoribosyltransferase (HPRT) gene knockout rabbits using recombinant adeno-associated virus-mediated homologous recombination and SCNT. Gene trap strategies were employed to enhance the gene targeting rates. The male and female gene knockout fibroblast cell lines were derived by different strategies. When male HPRT knockout cells were used for SCNT, no live rabbits were obtained. However, when female HPRT(+/-) cells were used for SCNT, live, healthy rabbits were generated. The cloned HPRT(+/-) rabbits were fertile at maturity. We demonstrate a new technique to produce gene-targeted rabbits. This approach may also be used in the genetic manipulation of different genes or in other species.

  15. 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.

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

    Science.gov (United States)

    Osiak, Anna; Radecke, Frank; Guhl, Eva; Radecke, Sarah; Dannemann, Nadine; Lütge, Fabienne; Glage, Silke; Rudolph, Cornelia; Cantz, Tobias; Schwarz, Klaus; Heilbronn, Regine; Cathomen, Toni

    2011-01-01

    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.

  17. Establishment of murine Smad5 double knockout ES cells and the studies on their properties

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Smad5 is an intracellular transducer of TGF-b signals. Targeteddisruption of murine Smad5 gene resulted in embryonic lethal. To study the function of Smad5 in organgenesis, we generated Smad5 double knockout ES cells by homologous recombination. We deleted the neo gene of the Smad5 targeted ES cells using Cre-LoxP system. Smad5 double knockout ES cells were obtained by transfecting the targeted ES cells using the same targeting construct. The results of chimeric study showed that Smad5 might play an important role during the development of heart and neural tube. Smad5 double knockout ES cells formed teratoma when injected subcutaneously into nude mice. They differentiated into several types of cells, including neural cells, muscle cells, chondrocytes, endothelial cells and glandaceous cells. Smad5 double knockout ES cells are useful for studying the function of Smad5 mediated TGF- b during the organgenesis and the in vitro differentiation of ES cells.

  18. 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.

  19. A modified TALEN-based strategy for rapidly and efficiently generating knockout mice for kidney development studies.

    Science.gov (United States)

    Liu, Yunhong; Lv, Xiaoyan; Tan, Ruizhi; Liu, Tianming; Chen, Tielin; Li, Mi; Liu, Yuhang; Nie, Fang; Wang, Xiaoyan; Zhou, Puhui; Chen, Mianzhi; Zhou, Qin

    2014-01-01

    The transcription activator-like effector nucleases (TALENs) strategy has been widely used to delete and mutate genes in vitro. This strategy has begun to be used for in vivo systemic gene manipulation, but not in an organ-specific manner. In this study, we developed a modified, highly efficient TALEN strategy using a dual-fluorescence reporter. We used this modified strategy and, within 5 weeks, we successfully generated kidney proximal tubule-specific gene Ttc36 homozygous knockout mice. Unilateral nephrectomy was performed on the 6-week-old founders (F0) to identify the knockout genotype prior to the birth of the offspring. This strategy was found to have little effect on reproduction in the knockout mice and inheritability of the knockout genotypes. The modified TALEN knockout strategy in combination with unilateral nephrectomy can be readily used for studies of gene function in kidney development and diseases.

  20. A modified TALEN-based strategy for rapidly and efficiently generating knockout mice for kidney development studies.

    Directory of Open Access Journals (Sweden)

    Yunhong Liu

    Full Text Available The transcription activator-like effector nucleases (TALENs strategy has been widely used to delete and mutate genes in vitro. This strategy has begun to be used for in vivo systemic gene manipulation, but not in an organ-specific manner. In this study, we developed a modified, highly efficient TALEN strategy using a dual-fluorescence reporter. We used this modified strategy and, within 5 weeks, we successfully generated kidney proximal tubule-specific gene Ttc36 homozygous knockout mice. Unilateral nephrectomy was performed on the 6-week-old founders (F0 to identify the knockout genotype prior to the birth of the offspring. This strategy was found to have little effect on reproduction in the knockout mice and inheritability of the knockout genotypes. The modified TALEN knockout strategy in combination with unilateral nephrectomy can be readily used for studies of gene function in kidney development and diseases.

  1. Generation of hypoxanthine phosphoribosyltransferase gene knockout rabbits by homologous recombination and gene trapping through somatic cell nuclear transfer

    OpenAIRE

    Mingru Yin; Weihua Jiang; Zhenfu Fang; Pengcheng Kong; Fengying Xing; Yao Li; Xuejin Chen; Shangang Li

    2015-01-01

    The rabbit is a common animal model that has been employed in studies on various human disorders, and the generation of genetically modified rabbit lines is highly desirable. Female rabbits have been successfully cloned from cumulus cells, and the somatic cell nuclear transfer (SCNT) technology is well established. The present study generated hypoxanthine phosphoribosyltransferase (HPRT) gene knockout rabbits using recombinant adeno-associated virus-mediated homologous recombination and SCNT....

  2. Pol II-expressed shRNA knocks down Sod2 gene expression and causes phenotypes of the gene knockout in mice.

    Directory of Open Access Journals (Sweden)

    Xu-Gang Xia

    2006-01-01

    Full Text Available RNA interference (RNAi has been used increasingly for reverse genetics in invertebrates and mammalian cells, and has the potential to become an alternative to gene knockout technology in mammals. Thus far, only RNA polymerase III (Pol III-expressed short hairpin RNA (shRNA has been used to make shRNA-expressing transgenic mice. However, widespread knockdown and induction of phenotypes of gene knockout in postnatal mice have not been demonstrated. Previous studies have shown that Pol II synthesizes micro RNAs (miRNAs-the endogenous shRNAs that carry out gene silencing function. To achieve efficient gene knockdown in mammals and to generate phenotypes of gene knockout, we designed a construct in which a Pol II (ubiquitin C promoter drove the expression of an shRNA with a structure that mimics human miRNA miR-30a. Two transgenic lines showed widespread and sustained shRNA expression, and efficient knockdown of the target gene Sod2. These mice were viable but with phenotypes of SOD2 deficiency. Bigenic heterozygous mice generated by crossing these two lines showed nearly undetectable target gene expression and phenotypes consistent with the target gene knockout, including slow growth, fatty liver, dilated cardiomyopathy, and premature death. This approach opens the door of RNAi to a wide array of well-established Pol II transgenic strategies and offers a technically simpler, cheaper, and quicker alternative to gene knockout by homologous recombination for reverse genetics in mice and other mammalian species.

  3. Mapping ecologically relevant social behaviours by gene knockout in wild mice.

    Science.gov (United States)

    Chalfin, Lea; Dayan, Molly; Levy, Dana Rubi; Austad, Steven N; Miller, Richard A; Iraqi, Fuad A; Dulac, Catherine; Kimchi, Tali

    2014-08-05

    The laboratory mouse serves as an important model system for studying gene, brain and behavioural interactions. Powerful methods of gene targeting have helped to decipher gene-function associations in human diseases. Yet, the laboratory mouse, obtained after decades of human-driven artificial selection, inbreeding, and adaptation to captivity, is of limited use for the study of fitness-driven behavioural responses that characterize the ancestral wild house mouse. Here, we demonstrate that the backcrossing of wild mice with knockout mutant laboratory mice retrieves behavioural traits exhibited exclusively by the wild house mouse, thereby unmasking gene functions inaccessible in the domesticated mutant model. Furthermore, we show that domestication had a much greater impact on females than on males, erasing many behavioural traits of the ancestral wild female. Hence, compared with laboratory mice, wild-derived mutant mice constitute an improved model system to gain insights into neuronal mechanisms underlying normal and pathological sexually dimorphic social behaviours.

  4. Transgenic gene knock-outs: functional genomics and therapeutic target selection.

    Science.gov (United States)

    Harris, S; Foord, S M

    2000-11-01

    The completion of the first draft of the human genome presents both a tremendous opportunity and enormous challenge to the pharmaceutical industry since the whole community, with few exceptions, will soon have access to the same pool of candidate gene sequences from which to select future therapeutic targets. The commercial imperative to select and pursue therapeutically relevant genes from within the overall content of the genome will be particularly intense for those gene families that currently represent the chemically tractable or 'drugable' gene targets. As a consequence the emphasis within exploratory research has shifted towards the evaluation and adoption of technology platforms that can add additional value to the gene selection process, either through functional studies or direct/indirect measures of disease alignment e.g., genetics, differential gene expression, proteomics, tissue distribution, comparative species data etc. The selection of biological targets for the development of potential new medicines relies, in part, on the quality of the in vivo biological data that correlates a particular molecular target with the underlying pathophysiology of a disease. Within the pharmaceutical industry, studies employing transgenic animals and, in particular, animals with specific gene deletions are playing an increasingly important role in the therapeutic target gene selection, drug candidate selection and product development phases of the overall drug discovery process. The potential of phenotypic information from gene knock-outs to contribute to a high-throughput target selection/validation strategy has hitherto been limited by the resources required to rapidly generate and characterise a large number of knock-out transgenics in a timely fashion. The offerings of several companies that provide an opportunity to overcome these hurdles, albeit at a cost, are assessed with respect to the strategic business needs of the pharmaceutical industry.

  5. Effects of HAb18G/CD147 knockout on hepatocellular carcinoma cells in vitro using a novel zinc-finger nuclease-targeted gene knockout approach.

    Science.gov (United States)

    Li, Hong-Wei; Yang, Xiang-Min; Tang, Juan; Wang, Shi-Jie; Chen, Zhi-Nan; Jiang, Jian-Li

    2015-03-01

    HAb18G/CD147 belongs to the immunoglobulin superfamily and predominantly functions as an inducer of matrix metalloproteinase secretion for tumor invasion and metastasis. This study was designed to investigate the effects of HAb18G/CD147 knockout on hepatocellular carcinoma cells using zinc-finger nuclease (ZFNs)-targeted gene knockout approach. The HCC cell line SMMC-7721 was used for ZFNs-targeted cleavage of the HAb18G/CD147 gene. RT-PCR and Western blot assays were used to detect HAb18G/CD147 expression. HAb18G phenotypic changes following HAb18G/CD147 knockout in SMMC-K7721 cells were assessed using tumor cell adhesion, invasion, migration and colony formation and flow cytometric assays. These data demonstrated that tumor cell adhesion, invasion, migration, and colony formation capabilities of SMMC-K7721 were significantly reduced compared to parental cells or SMMC-7721 with re-expression of HAb18G/CD147 protein transfected with HAb18G/CD147 cDNA. Moreover, knockout of HAb18G/CD147 expression also induced SMMC-K7721 cells to undergo apoptosis compared to SMMC-7721 and SMMC-R7721 (P CD147 reduced p53 levels in SMMC-R7721 cells, possibly through inhibition of the PI3K-Akt-MDM2 signaling pathway. The findings provide a novel insight into the mechanisms underlying HAb18G/CD147-induced progression of HCC cells.

  6. Muc2和DCN基因敲除小鼠食子现象的初步研究%Preliminary study of kronismus in Muc2 and DCN gene knockout mice

    Institute of Scientific and Technical Information of China (English)

    李巍; 贺国洋

    2013-01-01

    Objective To explore the differences in kronismus of Muc2 and DCN gene knockout mice. Methods Knockout homozygote males and females ( Muc2 -/ - ,DCN -/ - ) mice were mated respectively according to 1 :1 or 1 ;2 ratio. The average litter size of 1 - 3 generations, parity interval time, and kronismus in Muc2 and DCN gene knockout mice were observed. Results An average litter size of Muc2 gene knockout mice was 5.80 ±0.95. The average birth interval time was 42. 29 ±2. 28 days. The average DCN knockout mice seed production was 3. 85 ±0. 76, and the average birth interval time was 24. 86 ± 10. 42 days. There were significant differences between Muc2 and DCN gene knockout mice in the average litter size, parity interval time, and kronismus. Conclusions The reproductive performance of the two groups of gene knockout mice are different, indicating that Muc2 and DCN genes may be associated with reproductive function.%目的 探讨Muc2和DCN基因敲除小鼠繁殖能力和食子现象的异同.方法 分别将Muc2和DCN基因敲除纯合子雌雄小鼠按1∶1或1∶的合笼,观察1~3胎产仔量、胎次间隔时间、出生存活率和食子现象.结果 Muc2基因敲除小鼠平均产子量5.80±0.95只,平均胎次间隔时间(42.29±2.28) d;DCN基因敲除小鼠平均产子量3.85±0.76只,平均胎次间隔时间(24.86±10.42)d.Muc2和DCN基因敲除小鼠在产仔量、胎次间隔时间、出生存活率和食子率差异均存在显著性.结论 两组基因敲除小鼠繁殖性能有差异,揭示可能与Muc2和DCN基因有关.

  7. Knockout of exogenous EGFP gene in porcine somatic cells using zinc-finger nucleases

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, Masahito [Japan Science and Technology Agency (JST), ERATO, Nakauchi Stem Cell and Organ Regeneration Project, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639 (Japan); Department of Life Sciences, School of Agriculture, Meiji University, 1-1-1 Higashimita, Tama-ku, Kawasaki, Kanagawa 214-8571 (Japan); Umeyama, Kazuhiro [Department of Life Sciences, School of Agriculture, Meiji University, 1-1-1 Higashimita, Tama-ku, Kawasaki, Kanagawa 214-8571 (Japan); International Cluster for Bio-Resource Research, Meiji University, 1-1-1 Higashimita, Tama-ku, Kawasaki, Kanagawa 214-8571 (Japan); Matsunari, Hitomi [Department of Life Sciences, School of Agriculture, Meiji University, 1-1-1 Higashimita, Tama-ku, Kawasaki, Kanagawa 214-8571 (Japan); Takayanagi, Shuko [Japan Science and Technology Agency (JST), ERATO, Nakauchi Stem Cell and Organ Regeneration Project, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639 (Japan); Department of Life Sciences, School of Agriculture, Meiji University, 1-1-1 Higashimita, Tama-ku, Kawasaki, Kanagawa 214-8571 (Japan); Haruyama, Erika; Nakano, Kazuaki; Fujiwara, Tsukasa; Ikezawa, Yuka [Department of Life Sciences, School of Agriculture, Meiji University, 1-1-1 Higashimita, Tama-ku, Kawasaki, Kanagawa 214-8571 (Japan); Nakauchi, Hiromitsu [Japan Science and Technology Agency (JST), ERATO, Nakauchi Stem Cell and Organ Regeneration Project, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639 (Japan); Center for Stem Cell Biology and Regenerative Medicine, Institute of Medical Science, Tokyo University, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639 (Japan); and others

    2010-11-05

    Research highlights: {yields} EGFP gene integrated in porcine somatic cells could be knocked out using the ZFN-KO system. {yields} ZFNs induced targeted mutations in porcine primary cultured cells. {yields} 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.

  8. Enhanced antinociceptive effects of morphine in histamine H2 receptor gene knockout mice.

    Science.gov (United States)

    Mobarakeh, Jalal Izadi; Takahashi, Kazuhiro; Sakurada, Shinobu; Kuramasu, Atsuo; Yanai, Kazuhiko

    2006-09-01

    We have previously shown that antinociceptive effects of morphine are enhanced in histamine H1 receptor gene knockout mice. In the present study, involvement of supraspinal histamine H2 receptor in antinociception by morphine was examined using histamine H2 receptor gene knockout (H2KO) mice and histamine H2 receptor antagonists. Antinociception was evaluated by assays for thermal (hot-plate, tail-flick and paw-withdrawal tests), mechanical (tail-pressure test) and chemical (formalin and capsaicin tests) stimuli. Thresholds for pain perception in H2KO mice were higher than wild-type mice. Antinociceptive effects of intracerebroventricularly administered morphine were enhanced in the H2KO mice compared to wild-type mice. Intracerebroventricular co-administration of morphine and cimetidine produced significant antinociceptive effects in the wild-type mice when compared to morphine or cimetidine alone. Furthermore, zolantidine, a selective and hydrophobic H2 receptor antagonist, enhanced the effects of morphine in all nociceptive assays examined. These results suggest that histamine exerts inhibitory effects on morphine-induced antinociception through H2 receptors at the supraspinal level. Our present and previous studies suggest that H1 and H2 receptors cooperatively function to modulate pain perception in the central nervous system.

  9. 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.

  10. Revealing the essentiality of multiple archaeal pcna genes using a mutant propagation assay based on an improved knockout method

    DEFF Research Database (Denmark)

    Zhang, Changyi; Guo, Li; Deng, Ling;

    2010-01-01

    Organisms belonging to the Crenarchaeota lineage contain three PCNA subunits (proliferating cell nuclear antigen) while those in Euryarchaeota have only one as for Eukarya. To study the mechanism of archaeal sliding clamps, we sought to generate knockouts for each pcna gene in Sulfolobus islandic...... genes are absolutely required for host cell viability. Because the only prerequisite for this assay is to generate a MID transformant, this approach can be applied generally to any microorganisms proficient in homologous recombination....

  11. Gene expression profiling studies in regenerating nerves in a mouse model for CMT1X: uninjured Cx32-knockout peripheral nerves display expression profile of injured wild type nerves.

    Science.gov (United States)

    Freidin, Mona; Asche-Godin, Samantha; Abrams, Charles K

    2015-01-01

    X-linked Charcot-Marie-Tooth disease (CMT1X) is an inherited peripheral neuropathy caused by mutations in GJB1, the human gene for Connexin32 (Cx32). This present study uses Ilumina Ref8-v2 BeadArray to examine the expression profiles of injured and uninjured sciatic nerves at 5, 7, and 14 days post-crush injury (dpi) from Wild Type (WT) and Cx32-knockout (Cx32KO) mice to identify the genes and signaling pathways that are dysregulated in the absence of Schwann cell Cx32. Given the assumption that loss of Schwann cell Cx32 disrupts the regeneration and maintenance of myelinated nerve leading to a demyelinating neuropathy in CMT1X, we initially hypothesized that nerve crush injury would result in significant increases in differential gene expression in Cx32KO mice relative to WT nerves. However, microarray analysis revealed a striking collapse in the number of differentially expressed genes at 5 and 7 dpi in Cx32KO nerves relative to WT, while uninjured and 14 dpi time points showed large numbers of differentially regulated genes. Further comparisons within each genotype showed limited changes in Cx32KO gene expression following crush injury when compared to uninjured Cx32KO nerves. By contrast, WT nerves exhibited robust changes in gene expression at 5 and 7 dpi with no significant differences in gene expression by 14dpi relative to uninjured WT nerve samples. Taken together, these data suggest that the gene expression profile in uninjured Cx32KO sciatic nerve strongly resembles that of a WT nerve following injury and that loss of Schwann cell Cx32 leads to a basal state of gene expression similar to that of an injured WT nerve. These findings support a role for Cx32 in non-myelinating and regenerating populations of Schwann cells in normal axonal maintenance in re-myelination, and regeneration of peripheral nerve following injury. Disruption of Schwann cell-axonal communication in CMT1X may cause dysregulation of signaling pathways that are essential for the

  12. Effect of chronic valproic Acid treatment on hepatic gene expression profile in wfs1 knockout mouse.

    Science.gov (United States)

    Punapart, Marite; Eltermaa, Mall; Oflijan, Julia; Sütt, Silva; Must, Anne; Kõks, Sulev; Schalkwyk, Leonard C; Fernandes, Catherine; Vasar, Eero; Soomets, Ursel; Terasmaa, Anton

    2014-01-01

    Valproic acid (VPA) is a widely used anticonvulsant and mood-stabilizing drug whose use is often associated with drug-induced weight gain. Treatment with VPA has been shown to upregulate Wfs1 expression in vitro. Aim of the present study was to compare the effect of chronic VPA treatment in wild type (WT) and Wfs1 knockout (KO) mice on hepatic gene expression profile. Wild type, Wfs1 heterozygous, and homozygous mice were treated with VPA for three months (300 mg/kg i.p. daily) and gene expression profiles in liver were evaluated using Affymetrix Mouse GeneChip 1.0 ST array. We identified 42 genes affected by Wfs1 genotype, 10 genes regulated by VPA treatment, and 9 genes whose regulation by VPA was dependent on genotype. Among the genes that were regulated differentially by VPA depending on genotype was peroxisome proliferator-activated receptor delta (Ppard), whose expression was upregulated in response to VPA treatment in WT, but not in Wfs1 KO mice. Thus, regulation of Ppard by VPA is dependent on Wfs1 genotype.

  13. Site-Directed Genome Knockout in Chicken Cell Line and Embryos Can Use CRISPR/Cas Gene Editing Technology

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    Qisheng Zuo

    2016-06-01

    Full Text Available The present study established an efficient genome editing approach for the construction of stable transgenic cell lines of the domestic chicken (Gallus gallus domesticus. Our objectives were to facilitate the breeding of high-yield, high-quality chicken strains, and to investigate gene function in chicken stem cells. Three guide RNA (gRNAs were designed to knockout the C2EIP gene, and knockout efficiency was evaluated in DF-1 chicken fibroblasts and chicken ESCs using the luciferase single-strand annealing (SSA recombination assay, T7 endonuclease I (T7EI assay, and TA clone sequencing. In addition, the polyethylenimine-encapsulated Cas9/gRNA plasmid was injected into fresh fertilized eggs. At 4.5 d later, frozen sections of the embryos were prepared, and knockout efficiency was evaluated by the T7EI assay. SSA assay results showed that luciferase activity of the vector expressing gRNA-3 was double that of the control. Results of the T7EI assay and TA clone sequencing indicated that Cas9/gRNA vector-mediated gene knockdown efficiency was approximately 27% in both DF-1 cells and ESCs. The CRISPR/Cas9 vector was also expressed in chicken embryos, resulting in gene knockdown in three of the 20 embryos (gene knockdown efficiency 15%. Taken together, our results indicate that the CRISPR/Cas9 system can mediate stable gene knockdown at the cell and embryo levels in domestic chickens.

  14. Global analysis of gene expression in the developing brain of Gtf2ird1 knockout mice.

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    Jennifer O'Leary

    Full Text Available BACKGROUND: 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. METHODOLOGY/PRINCIPAL FINDINGS: 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. CONCLUSIONS/SIGNIFICANCE: 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.

  15. Host knockout of E-prostanoid 2 receptors reduces tumor growth and causes major alterations of gene expression in prostaglandin E2-producing tumors

    Science.gov (United States)

    Asting, Annika Gustafsson; Iresjö, Britt-Marie; Nilsberth, Camilla; Smedh, Ulrika; Lundholm, Kent

    2017-01-01

    Prostaglandin E2 (PGE2) is elevated in a variety of malignant tumors and has been shown to affect several hallmarks of cancer. Accordingly, the PGE2 receptor, E-prostanoid 2 (EP2), has been reported to be associated with patient survival and reduced tumor growth in EP2-knockout mice. Thus, the aim of the present study was to screen for major gene expression alterations in tumor tissue growing in EP2-knockout mice. EP2-knockout mice were bred and implanted with EP2 receptor-expressing and PGE2-producing epithelial-like tumors. Tumor tissue and plasma were collected and used for analyses with gene expression microarrays and multiplex enzyme-linked immunosorbent assays. Tumor growth, acute phase reactions/systemic inflammation and the expression of interleukin-6 were reduced in EP2-knockout tumor-bearing mice. Several hundreds of genes displayed major changes of expression in the tumor tissue when grown in EP2-knockout mice. Such gene alterations involved several different cellular functions, including stemness, migration and cell signaling. Besides gene expression, several long non-coding RNAs were downregulated in the tumors from the EP2-knockout mice. Overall, PGE2 signaling via host EP2 receptors affected a large number of different genes involved in tumor progression based on signaling between host stroma and tumor cells, which caused reduced tumor growth. PMID:28123585

  16. Effects of alpha-AMPK knockout on exercise-induced gene activation in mouse skeletal muscle

    DEFF Research Database (Denmark)

    Jørgensen, Sebastian Beck; Wojtaszewski, Jørgen; Viollet, Benoit

    2005-01-01

    We tested the hypothesis that 5'AMP-activated protein kinase (AMPK) plays an important role in regulating the acute, exercise-induced activation of metabolic genes in skeletal muscle, which were dissected from whole-body a2- and a1-AMPK knockout (KO) and wild-type (WT) mice at rest, after treadmi...

  17. 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

    2007-01-01

    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 imple

  18. 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.

  19. GeneKnockout by Targeted Mutagenesis in a Hemimetabolous Insect, the Two-Spotted Cricket Gryllus bimaculatus, using TALENs.

    Science.gov (United States)

    Watanabe, Takahito; Noji, Sumihare; Mito, Taro

    2016-01-01

    Hemimetabolous, or incompletely metamorphosing, insects are phylogenetically basal. These insects include many deleterious species. The cricket, Gryllus bimaculatus, is an emerging model for hemimetabolous insects, based on the success of RNA interference (RNAi)-based gene-functional analyses and transgenic technology. Taking advantage of genome-editing technologies in this species would greatly promote functional genomics studies. Genome editing using transcription activator-like effector nucleases (TALENs) has proven to be an effective method for site-specific genome manipulation in various species. TALENs are artificial nucleases that are capable of inducing DNA double-strand breaks into specified target sequences. Here, we describe a protocol for TALEN-based gene knockout in G. bimaculatus, including a mutant selection scheme via mutation detection assays, for generating homozygous knockout organisms.

  20. Efficient gene knockout in goats using CRISPR/Cas9 system.

    Directory of Open Access Journals (Sweden)

    Wei Ni

    Full Text Available The CRISPR/Cas9 system has been adapted as an efficient genome editing tool in laboratory animals such as mice, rats, zebrafish and pigs. Here, we report that CRISPR/Cas9 mediated approach can efficiently induce monoallelic and biallelic gene knockout in goat primary fibroblasts. Four genes were disrupted simultaneously in goat fibroblasts by CRISPR/Cas9-mediated genome editing. The single-gene knockout fibroblasts were successfully used for somatic cell nuclear transfer (SCNT and resulted in live-born goats harboring biallelic mutations. The CRISPR/Cas9 system represents a highly effective and facile platform for targeted editing of large animal genomes, which can be broadly applied to both biomedical and agricultural applications.

  1. Gene replacement in Mycobacterium chelonae: application to the construction of porin knock-out mutants.

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    Vinicius Calado Nogueira de Moura

    Full Text Available Mycobacterium chelonae is a rapidly growing mycobacterial opportunistic pathogen closely related to Mycobacterium abscessus that causes cornea, skin and soft tissue infections in humans. Although M. chelonae and the emerging mycobacterial pathogen M. abscessus have long been considered to belong to the same species, these two microorganisms considerably differ in terms of optimum growth temperature, drug susceptibility, pathogenicity and the types of infection they cause. The whole genome sequencing of clinical isolates of M. chelonae and M. abscessus is opening the way to comparative studies aimed at understanding the biology of these pathogens and elucidating the molecular bases of their pathogenicity and biocide resistance. Key to the validation of the numerous hypotheses that this approach will raise, however, is the availability of genetic tools allowing for the expression and targeted mutagenesis of genes in these species. While homologous recombination systems have recently been described for M. abscessus, genetic tools are lacking for M. chelonae. We here show that two different allelic replacement methods, one based on mycobacteriophage-encoded recombinases and the other on a temperature-sensitive plasmid harboring the counterselectable marker sacB, can be used to efficiently disrupt genes in this species. Knock-out mutants for each of the three porin genes of M. chelonae ATCC 35752 were constructed using both methodologies, one of which displays a significantly reduced glucose uptake rate consistent with decreased porin expression.

  2. Efficient TALEN-mediated gene knockout in livestock.

    Science.gov (United States)

    Carlson, Daniel F; Tan, Wenfang; Lillico, Simon G; Stverakova, Dana; Proudfoot, Chris; Christian, Michelle; Voytas, Daniel F; Long, Charles R; Whitelaw, C Bruce A; Fahrenkrug, Scott C

    2012-10-23

    Transcription activator-like effector nucleases (TALENs) are programmable nucleases that join FokI endonuclease with the modular DNA-binding domain of TALEs. Although zinc-finger nucleases enable a variety of genome modifications, their application to genetic engineering of livestock has been slowed by technical limitations of embryo-injection, culture of primary cells, and difficulty in producing reliable reagents with a limited budget. In contrast, we found that TALENs could easily be manufactured and that over half (23/36, 64%) demonstrate high activity in primary cells. Cytoplasmic injections of TALEN mRNAs into livestock zygotes were capable of inducing gene KO in up to 75% of embryos analyzed, a portion of which harbored biallelic modification. We also developed a simple transposon coselection strategy for TALEN-mediated gene modification in primary fibroblasts that enabled both enrichment for modified cells and efficient isolation of modified colonies. Coselection after treatment with a single TALEN-pair enabled isolation of colonies with mono- and biallelic modification in up to 54% and 17% of colonies, respectively. Coselection after treatment with two TALEN-pairs directed against the same chromosome enabled the isolation of colonies harboring large chromosomal deletions and inversions (10% and 4% of colonies, respectively). TALEN-modified Ossabaw swine fetal fibroblasts were effective nuclear donors for cloning, resulting in the creation of miniature swine containing mono- and biallelic mutations of the LDL receptor gene as models of familial hypercholesterolemia. TALENs thus appear to represent a highly facile platform for the modification of livestock genomes for both biomedical and agricultural applications.

  3. Characterisation of iunH gene knockout strain from Mycobacterium tuberculosis

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    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

  4. Characterisation of iunH gene knockout strain from Mycobacterium tuberculosis

    Science.gov (United States)

    Villela, Anne Drumond; Rodrigues, Valnês da Silva; Pinto, Antônio Frederico Michel; Wink, Priscila Lamb; Sánchez-Quitian, Zilpa Adriana; Petersen, Guilherme Oliveira; Campos, Maria Martha; Basso, Luiz Augusto; Santos, Diógenes Santiago

    2017-01-01

    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 target for drug

  5. Establishment of liver specific glucokinase gene knockout mice:a new animal model for screening anti-diabetic drugs

    Institute of Scientific and Technical Information of China (English)

    Ya-li ZHANG; Xiao-hong TAN; Mei-fang XIAO; Hui LI; Yi-qing Mao; Xiao YANG; Huan-ran TAN

    2004-01-01

    AIM: To characterize the liver-specific role of glucokinase in maintaining glucose homeostasis and to create an animal model for diabetes. METHODS: We performed hepatocyte-specific gene knockout of glucokinase in mice using Cre-loxP gene targeting strategy. First, two directly repeated loxP sequences were inserted to flank the exon 9 and exon 10 of glucokinase in genomic DNA. To achieve this, linearized targeting vector was electroporated into ES cells. Then G418- and Gancyclovir-double-resistant clones were picked and screened by PCR analysis and the positives identified by PCR were confirmed by Southern blot. A targeted clone was selected for microinjection into C57BL/6J blastocysts and implanted into pseudopregnant FVB recipient. Chimeric mice and their offspring were analyzed by Southern blot. Then by intercrossing the Alb-Cre transgenic mice with mice containing a conditional gk allele, we obtained mice with liver-specific glucokinase gene knockout. RESULTS: Among 161 double resistant clones 4 were positive to PCR and Southern blot and only one was used for further experiments. Eventually we generated the liver specific glucokinase knockout mice. These mice showed increased glucose level with age and at the age of 6 weeks fasting blood glucose level was significantly higher than control and they also displayed impaired glucose tolerance. CONCLUSION: Our studies indicate that hepatic glucokinase plays an important role in glucose homeostasis and its deficiencies contribute to the development of diabetes. The liver glucokinase knockout mouse is an ideal animal model for MODY2, and it also can be applied for screening anti-diabetic drugs.

  6. True-breeding targeted gene knock-out in barley using designer TALE-nuclease in haploid cells.

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    Maia Gurushidze

    Full Text Available Transcription activator-like effector nucleases (TALENs are customizable fusion proteins able to cleave virtually any genomic DNA sequence of choice, and thereby to generate site-directed genetic modifications in a wide range of cells and organisms. In the present study, we expressed TALENs in pollen-derived, regenerable cells to establish the generation of instantly true-breeding mutant plants. A gfp-specific TALEN pair was expressed via Agrobacterium-mediated transformation in embryogenic pollen of transgenic barley harboring a functional copy of gfp. Thanks to the haploid nature of the target cells, knock-out mutations were readily detected, and homozygous primary mutant plants obtained following genome duplication. In all, 22% of the TALEN transgenics proved knocked out with respect to gfp, and the loss of function could be ascribed to the deletions of between four and 36 nucleotides in length. The altered gfp alleles were transmitted normally through meiosis, and the knock-out phenotype was consistently shown by the offspring of two independent mutants. Thus, here we describe the efficient production of TALEN-mediated gene knock-outs in barley that are instantaneously homozygous and non-chimeric in regard to the site-directed mutations induced. This TALEN approach has broad applicability for both elucidating gene function and tailoring the phenotype of barley and other crop species.

  7. Claudin-2 knockout by TALEN-mediated gene targeting in MDCK cells: claudin-2 independently determines the leaky property of tight junctions in MDCK cells.

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    Shinsaku Tokuda

    Full Text Available Tight junctions (TJs regulate the movements of substances through the paracellular pathway, and claudins are major determinants of TJ permeability. Claudin-2 forms high conductive cation pores in TJs. The suppression of claudin-2 expression by RNA interference in Madin-Darby canine kidney (MDCK II cells (a low-resistance strain of MDCK cells was shown to induce a three-fold increase in transepithelial electrical resistance (TER, which, however, was still lower than in high-resistance strains of MDCK cells. Because RNA interference-mediated knockdown is not complete and only reduces gene function, we considered the possibility that the remaining claudin-2 expression in the knockdown study caused the lower TER in claudin-2 knockdown cells. Therefore, we investigated the effects of claudin-2 knockout in MDCK II cells by establishing claudin-2 knockout clones using transcription activator-like effector nucleases (TALENs, a recently developed genome editing method for gene knockout. Surprisingly, claudin-2 knockout increased TER by more than 50-fold in MDCK II cells, and TER values in these cells (3000-4000 Ω·cm2 were comparable to those in the high-resistance strains of MDCK cells. Claudin-2 re-expression restored the TER of claudin-2 knockout cells dependent upon claudin-2 protein levels. In addition, we investigated the localization of claudin-1, -2, -3, -4, and -7 at TJs between control MDCK cells and their respective knockout cells using their TALENs. Claudin-2 and -7 were less efficiently localized at TJs between control and their knockout cells. Our results indicate that claudin-2 independently determines the 'leaky' property of TJs in MDCK II cells and suggest the importance of knockout analysis in cultured cells.

  8. Conditional knockout of the Slc5a6 gene in mouse intestine impairs biotin absorption.

    Science.gov (United States)

    Ghosal, Abhisek; Lambrecht, Nils; Subramanya, Sandeep B; Kapadia, Rubina; Said, Hamid M

    2013-01-01

    The Slc5a6 gene expresses a plasma membrane protein involved in the transport of the water-soluble vitamin biotin; the transporter is commonly referred to as the sodium-dependent multivitamin transporter (SMVT) because it also transports pantothenic acid and lipoic acid. The relative contribution of the SMVT system toward carrier-mediated biotin uptake in the native intestine in vivo has not been established. We used a Cre/lox technology to generate an intestine-specific (conditional) SMVT knockout (KO) mouse model to address this issue. The KO mice exhibited absence of expression of SMVT in the intestine compared with sex-matched littermates as well as the expected normal SMVT expression in other tissues. About two-thirds of the KO mice died prematurely between the age of 6 and 10 wk. Growth retardation, decreased bone density, decreased bone length, and decreased biotin status were observed in the KO mice. Microscopic analysis showed histological abnormalities in the small bowel (shortened villi, dysplasia) and cecum (chronic active inflammation, dysplasia) of the KO mice. In vivo (and in vitro) transport studies showed complete inhibition in carrier-mediated biotin uptake in the intestine of the KO mice compared with their control littermates. These studies provide the first in vivo confirmation in native intestine that SMVT is solely responsible for intestinal biotin uptake. These studies also provide evidence for a casual association between SMVT function and normal intestinal health.

  9. Myostatin gene knockout mediated by Cas9-D10A nickase in chicken DF1 cells without off-target effect

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    Jeong Hyo Lee

    2017-05-01

    Full Text Available Objective Based on rapid advancement of genetic modification techniques, genomic editing is expected to become the most efficient tool for improvement of economic traits in livestock as well as poultry. In this study, we examined and verified the nickase of mutated CRISPR-associated protein 9 (Cas9 to modulate the specific target gene in chicken DF1 cells. Methods Chicken myostatin which inhibits muscle cell growth and differentiation during myogenesis was targeted to be deleted and mutated by the Cas9-D10A nickase. After co-transfection of the nickase expression vector with green fluorescent gene (GFP gene and targeted multiplex guide RNAs (gRNAs, the GFP-positive cells were sorted out by fluorescence-activated cell sorting procedure. Results Through the genotyping analysis of the knockout cells, the mutant induction efficiency was 100% in the targeted site. Number of the deleted nucleotides ranged from 2 to 39 nucleotide deletion. There was no phenotypic difference between regular cells and knockout cells. However, myostatin protein was not apparently detected in the knockout cells by Western blotting. Additionally, six off-target sites were predicted and analyzed but any non-specific mutation in the off-target sites was not observed. Conclusion The knockout technical platform with the nickase and multiplex gRNAs can be efficiently and stablely applied to functional genomics study in poultry and finally adapted to generate the knockout poultry for agribio industry.

  10. ZO-1 knockout by TALEN-mediated gene targeting in MDCK cells: involvement of ZO-1 in the regulation of cytoskeleton and cell shape.

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    Shinsaku Tokuda

    Full Text Available ZO-1, ZO-2 and ZO-3 are tight junction-associated scaffold proteins that bind to transmembrane proteins of tight junctions and the underlying cytoskeleton. ZO-1 is involved in the regulation of cytoskeletal organization, but its detailed molecular mechanism is less well understood. Gene knockout is an ideal method to investigate the functions of proteins that might have redundant functions such as ZO proteins, when compared with methods such as RNA interference-mediated suppression of gene expression. In this study we applied transcription activator-like effector nucleases (TALENs, a recently developed genome editing method for gene knockout, and established ZO-1 knockout clones in Madin-Darby canine kidney (MDCK cells. ZO-1 knockout induced striking changes in myosin organization at cell-cell contacts and disrupted the localization of tight junction proteins; these findings were previously unseen in studies of ZO-1 knockdown by RNA interference. Rescue experiments revealed that trace ZO-1 expression reversed these changes while excessive ZO-1 expression induced an intensive zigzag shape of cell-cell junctions. These results suggest a role for ZO-1 in the regulation of cytoskeleton and shape of cell-cell junctions in MDCK cells and indicate the advantage of knockout analysis in cultured cells.

  11. Inhibition of scratching behaviour caused by contact dermatitis in histidine decarboxylase gene knockout mice.

    Science.gov (United States)

    Seike, M; Ikeda, M; Kodama, H; Terui, T; Ohtsu, H

    2005-03-01

    A neuronal system dedicated to itch consists of primary afferent and spinothalamic projection neurons. Histamine is thought to be one of the main mediators for the transmission of itch sensation. However, there are little available information on the role of histamine in scratching behaviour and sensory transmission of atopic dermatitis and chronic eczema. In the present study, the role of histamine in scratching behaviour and neural conduction of sensation in the chronic eczema model was investigated by using l-histidine decarboxylase (HDC) gene knockout mice lacking histamine. The chronic contact dermatitis was induced with daily application of diphenylcyclopropenone (DCP) on a hind paw of HDC (+/+) and HDC (-/-) mice for 2 months. The observation of scratching behaviour and the hot-plate test were performed in both mice. Histological studies were performed in the skin and spinal cord tissues. Histological examination revealed that both HDC (+/+) and HDC (-/-) mice displayed the similar extent of inflammatory cell infiltration, hyperplastic epidermis and newly spreading of neuronal processes in the skin tissue. Scratching behaviour was exclusively induced in HDC (+/+) mice, whereas it was barely observed in HDC (-/-) mice. The expression of c-Fos was specifically upregulated in HDC (+/+) mice in lamina I of the spinal dorsal horn following repeated DCP application. Scratching behaviour in chronic contact dermatitis in mice was thought mainly mediated with histamine. The afferent pathway of sensation in chronic contact dermatitis model may connect with the central nervous system through lamina I of the spinal dorsal horn.

  12. Prion protein (PrP) gene-knockout cell lines: insight into functions of the PrP

    OpenAIRE

    Sakudo, Akikazu; Onodera, Takashi

    2015-01-01

    Elucidation of prion protein (PrP) functions is crucial to fully understand prion diseases. A major approach to studying PrP functions is the use of PrP gene-knockout (Prnp −/−) mice. So far, six types of Prnp −/− mice have been generated, demonstrating the promiscuous functions of PrP. Recently, other PrP family members, such as Doppel and Shadoo, have been found. However, information obtained from comparative studies of structural and functional analyses of these PrP family proteins do not ...

  13. 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.

  14. Investigation on the Metabolic Regulation of pgi gene knockout Escherichia coli by Enzyme Activities and Intracellular Metabolite Concentrations

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    Nor ‘Aini, A. R.

    2006-01-01

    Full Text Available An integrated analysis of the cell growth characteristics, enzyme activities, intracellular metabolite concentrations was made to investigate the metabolic regulation of pgi gene knockout Escherichia coli based on batch culture and continuous culture which was performed at the dilution rate of 0.2h-1. The enzymatic study identified that pathways of pentose phosphate, ED pathway and glyoxylate shunt were all active in pgi mutant. The glycolysis enzymes i.e glyceraldehyde-3-phosphate dehydrogenase, fructose diphosphatase, pyruvate kinase, triose phosphate isomerase were down regulated implying that the inactivation of pgi gene reduced the carbon flux through glycolytic pathway. Meanwhile, the pentose phosphate pathway was active as a major route for intermediary carbohydrate metabolism instead of glycolysis. The pentose phosphate pathway generates most of the major reducing co-factor NADPH as shown by the increased of NADPH/NADP+ ratio in the mutant when compared with the parent strain. The fermentative enzymes such as acetate kinase and lactate dehydrogenase were down regulated in the mutant. Knockout of pgi gene results in the significant increase in the intracellular concentration of glucose-6-phosphate and decrease in the concentration of oxaloacetate. The slow growth rate of the mutant was assumed to be affected by the accumulation of glucose-6-phosphate and imbalance of NADPH reoxidation.

  15. Generation of Stable Knockout Mammalian Cells by TALEN-Mediated Locus-Specific Gene Editing.

    Science.gov (United States)

    Mahata, Barun; Biswas, Kaushik

    2017-01-01

    Precise and targeted genome editing using Transcription Activator-Like Effector Endonucleases (TALENs) has been widely used and proven to be an extremely effective and specific knockout strategy in both cultured cells and animal models. The current chapter describes a protocol for the construction and generation of TALENs using serial and hierarchical digestion and ligation steps, and using the synthesized TALEN pairs to achieve locus-specific targeted gene editing in mammalian cell lines using a modified clonal selection strategy in an easy and cost-efficient manner.

  16. Hepatic Gene Expression Profiling in Nrf2 Knockout Mice after Long-Term High-Fat Diet-Induced Obesity

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    Dionysios V. Chartoumpekis

    2013-01-01

    Full Text Available Introduction. The transcription factor NFE2-related factor 2 (Nrf2 is a central regulator of antioxidant and detoxification gene expression in response to electrophilic or oxidative stress. Nrf2 has recently been shown to cross-talk with metabolic pathways, and its gene deletion protected mice from high-fat-diet-(HFD- induced obesity and insulin resistance. This study aimed to identify potential Nrf2-regulated genes of metabolic interest by comparing gene expression profiles of livers of wild-type (WT versus Nrf2 knockout (Nrf2-KO mice after a long-term HFD. Methods. WT and Nrf2-KO mice were fed an HFD for 180 days; total RNA was prepared from liver and used for microarray analysis and quantitative real-time RT-PCR (qRT-PCR. Results. The microarray analysis identified 601 genes that were differentially expressed between WT and Nrf2-KO mice after long-term HFD. Selected genes, including ones known to be involved in metabolic regulation, were prioritized for verification by qRT-PCR: Cyp7a1 and Fabp5 were significantly overexpressed in Nrf2-KO mice; in contrast, Car, Cyp2b10, Lipocalin 13, Aquaporin 8, Cbr3, Me1, and Nqo1 were significantly underexpressed in Nrf2-KO mice. Conclusion. Transcriptome profiling after HFD-induced obesity confirms that Nrf2 is implicated in liver metabolic gene networks. The specific genes identified here may provide insights into Nrf2-dependent mechanisms of metabolic regulation.

  17. Prion protein (PrP) gene-knockout cell lines: insight into functions of the PrP.

    Science.gov (United States)

    Sakudo, Akikazu; Onodera, Takashi

    2014-01-01

    Elucidation of prion protein (PrP) functions is crucial to fully understand prion diseases. A major approach to studying PrP functions is the use of PrP gene-knockout (Prnp (-/-)) mice. So far, six types of Prnp (-/-) mice have been generated, demonstrating the promiscuous functions of PrP. Recently, other PrP family members, such as Doppel and Shadoo, have been found. However, information obtained from comparative studies of structural and functional analyses of these PrP family proteins do not fully reveal PrP functions. Recently, varieties of Prnp (-/-) cell lines established from Prnp (-/-) mice have contributed to the analysis of PrP functions. In this mini-review, we focus on Prnp (-/-) cell lines and summarize currently available Prnp (-/-) cell lines and their characterizations. In addition, we introduce the recent advances in the methodology of cell line generation with knockout or knockdown of the PrP gene. We also discuss how these cell lines have provided valuable insights into PrP functions and show future perspectives.

  18. Improving cold storage and processing traits in potato through targeted gene knockout.

    Science.gov (United States)

    Clasen, Benjamin M; Stoddard, Thomas J; Luo, Song; Demorest, Zachary L; Li, Jin; Cedrone, Frederic; Tibebu, Redeat; Davison, Shawn; Ray, Erin E; Daulhac, Aurelie; Coffman, Andrew; Yabandith, Ann; Retterath, Adam; Haun, William; Baltes, Nicholas J; Mathis, Luc; Voytas, Daniel F; Zhang, Feng

    2016-01-01

    Cold storage of potato tubers is commonly used to reduce sprouting and extend postharvest shelf life. However, cold temperature stimulates the accumulation of reducing sugars in potato tubers. Upon high-temperature processing, these reducing sugars react with free amino acids, resulting in brown, bitter-tasting products and elevated levels of acrylamide--a potential carcinogen. To minimize the accumulation of reducing sugars, RNA interference (RNAi) technology was used to silence the vacuolar invertase gene (VInv), which encodes a protein that breaks down sucrose to glucose and fructose. Because RNAi often results in incomplete gene silencing and requires the plant to be transgenic, here we used transcription activator-like effector nucleases (TALENs) to knockout VInv within the commercial potato variety, Ranger Russet. We isolated 18 plants containing mutations in at least one VInv allele, and five of these plants had mutations in all VInv alleles. Tubers from full VInv-knockout plants had undetectable levels of reducing sugars, and processed chips contained reduced levels of acrylamide and were lightly coloured. Furthermore, seven of the 18 modified plant lines appeared to contain no TALEN DNA insertions in the potato genome. These results provide a framework for using TALENs to quickly improve traits in commercially relevant autotetraploid potato lines.

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

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    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.

  20. Modeling RNA polymerase competition: the effect of σ-subunit knockout and heat shock on gene transcription level

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    Seliverstov Alexandr V

    2011-01-01

    Full Text Available Abstract Background Modeling of a complex biological process can explain the results of experimental studies and help predict its characteristics. Among such processes is transcription in the presence of competing RNA polymerases. This process involves RNA polymerases collision followed by transcription termination. Results A mathematical and computer simulation model is developed to describe the competition of RNA polymerases during genes transcription on complementary DNA strands. E.g., in the barley Hordeum vulgare the polymerase competition occurs in the locus containing plastome genes psbA, rpl23, rpl2 and four bacterial type promoters. In heat shock experiments on isolated chloroplasts, a twofold decrease of psbA transcripts and even larger increase of rpl23-rpl2 transcripts were observed, which is well reproduced in the model. The model predictions are in good agreement with virtually all relevant experimental data (knockout, heat shock, chromatogram data, etc.. The model allows to hypothesize a mechanism of cell response to knockout and heat shock, as well as a mechanism of gene expression regulation in presence of RNA polymerase competition. The model is implemented for multiprocessor platforms with MPI and supported on Linux and MS Windows. The source code written in C++ is available under the GNU General Public License from the laboratory website. A user-friendly GUI version is also provided at http://lab6.iitp.ru/en/rivals. Conclusions The developed model is in good agreement with virtually all relevant experimental data. The model can be applied to estimate intensities of binding of the holoenzyme and phage type RNA polymerase to their promoters using data on gene transcription levels, as well as to predict characteristics of RNA polymerases and the transcription process that are difficult to measure directly, e.g., the intensity (frequency of holoenzyme binding to the promoter in correlation to its nucleotide composition and the

  1. Is altered expression of hepatic insulin-related genes in growth hormone receptor knockout mice due to GH resistance or a difference in biological life spans?

    Science.gov (United States)

    Panici, Jacob A; Wang, Feiya; Bonkowski, Michael S; Spong, Adam; Bartke, Andrzej; Pawlikowska, Ludmila; Kwok, Pui-Yan; Masternak, Michal M

    2009-11-01

    Growth hormone receptor knockout (GHRKO) mice live about 40%-55% longer than their normal (N) littermates. Previous studies of 21-month-old GHRKO and N mice showed major alterations of the hepatic expression of genes involved in insulin signaling. Differences detected at this age may have been caused by the knockout of the growth hormone receptor (GHR) or by differences in biological age between GHRKO and N mice. To address this question, we compared GHRKO and N mice at ages corresponding to the same percentage of median life span to see if the differences of gene expression persisted. Comparison of GHRKO and N mice at approximately 50% of biological life span showed significant differences in hepatic expression of all 14 analyzed genes. We conclude that these changes are due to disruption of GHR gene and the consequent suppression of growth hormone signaling rather than to differences in "biological age" between mutant and normal animals sampled at the same chronological age.

  2. Engineering Human Stem Cell Lines with Inducible Gene Knockout using CRISPR/Cas9.

    Science.gov (United States)

    Chen, Yuejun; Cao, Jingyuan; Xiong, Man; Petersen, Andrew J; Dong, Yi; Tao, Yunlong; Huang, Cindy Tzu-Ling; Du, Zhongwei; Zhang, Su-Chun

    2015-08-06

    Precise temporal control of gene expression or deletion is critical for elucidating gene function in biological systems. However, the establishment of human pluripotent stem cell (hPSC) lines with inducible gene knockout (iKO) remains challenging. We explored building iKO hPSC lines by combining CRISPR/Cas9-mediated genome editing with the Flp/FRT and Cre/LoxP system. We found that "dual-sgRNA targeting" is essential for biallelic knockin of FRT sequences to flank the exon. We further developed a strategy to simultaneously insert an activity-controllable recombinase-expressing cassette and remove the drug-resistance gene, thus speeding up the generation of iKO hPSC lines. This two-step strategy was used to establish human embryonic stem cell (hESC) and induced pluripotent stem cell (iPSC) lines with iKO of SOX2, PAX6, OTX2, and AGO2, genes that exhibit diverse structural layout and temporal expression patterns. The availability of iKO hPSC lines will substantially transform the way we examine gene function in human cells.

  3. Sertoli-cell-specific knockout of connexin 43 leads to multiple alterations in testicular gene expression in prepubertal mice

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    Sarah Giese

    2012-11-01

    A significant decline in human male reproductive function has been reported for the past 20 years but the molecular mechanisms remain poorly understood. However, recent studies showed that the gap junction protein connexin-43 (CX43; also known as GJA1 might be involved. CX43 is the predominant testicular connexin (CX in most species, including in humans. Alterations of its expression are associated with different forms of spermatogenic disorders and infertility. Men with impaired spermatogenesis often exhibit a reduction or loss of CX43 expression in germ cells (GCs and Sertoli cells (SCs. Adult male transgenic mice with a conditional knockout (KO of the Gja1 gene [referred to here as connexin-43 (Cx43] in SCs (SCCx43KO show a comparable testicular phenotype to humans and are infertile. To detect possible signaling pathways and molecular mechanisms leading to the testicular phenotype in adult SCCx43KO mice and to their failure to initiate spermatogenesis, the testicular gene expression of 8-day-old SCCx43KO and wild-type (WT mice was compared. Microarray analysis revealed that 658 genes were significantly regulated in testes of SCCx43KO mice. Of these genes, 135 were upregulated, whereas 523 genes were downregulated. For selected genes the results of the microarray analysis were confirmed using quantitative real-time PCR and immunostaining. The majority of the downregulated genes are GC-specific and are essential for mitotic and meiotic progression of spermatogenesis, including Stra8, Dazl and members of the DM (dsx and map-3 gene family. Other altered genes can be associated with transcription, metabolism, cell migration and cytoskeleton organization. Our data show that deletion of Cx43 in SCs leads to multiple alterations of gene expression in prepubertal mice and primarily affects GCs. The candidate genes could represent helpful markers for investigators exploring human testicular biopsies from patients showing corresponding spermatogenic deficiencies and for

  4. Efficient CRISPR/Cas9-Mediated Versatile, Predictable, and Donor-Free Gene Knockout in Human Pluripotent Stem Cells

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    Zhongliang Liu

    2016-09-01

    Full Text Available Loss-of-function studies in human pluripotent stem cells (hPSCs require efficient methodologies for lesion of genes of interest. Here, we introduce a donor-free paired gRNA-guided CRISPR/Cas9 knockout strategy (paired-KO for efficient and rapid gene ablation in hPSCs. Through paired-KO, we succeeded in targeting all genes of interest with high biallelic targeting efficiencies. More importantly, during paired-KO, the cleaved DNA was repaired mostly through direct end joining without insertions/deletions (precise ligation, and thus makes the lesion product predictable. The paired-KO remained highly efficient for one-step targeting of multiple genes and was also efficient for targeting of microRNA, while for long non-coding RNA over 8 kb, cleavage of a short fragment of the core promoter region was sufficient to eradicate downstream gene transcription. This work suggests that the paired-KO strategy is a simple and robust system for loss-of-function studies for both coding and non-coding genes in hPSCs.

  5. Modularly assembled designer TAL effector nucleases for targeted gene knockout and gene replacement in eukaryotes.

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    Li, Ting; Huang, Sheng; Zhao, Xuefeng; Wright, David A; Carpenter, Susan; Spalding, Martin H; Weeks, Donald P; Yang, Bing

    2011-08-01

    Recent studies indicate that the DNA recognition domain of transcription activator-like (TAL) effectors can be combined with the nuclease domain of FokI restriction enzyme to produce TAL effector nucleases (TALENs) that, in pairs, bind adjacent DNA target sites and produce double-strand breaks between the target sequences, stimulating non-homologous end-joining and homologous recombination. Here, we exploit the four prevalent TAL repeats and their DNA recognition cipher to develop a 'modular assembly' method for rapid production of designer TALENs (dTALENs) that recognize unique DNA sequence up to 23 bases in any gene. We have used this approach to engineer 10 dTALENs to target specific loci in native yeast chromosomal genes. All dTALENs produced high rates of site-specific gene disruptions and created strains with expected mutant phenotypes. Moreover, dTALENs stimulated high rates (up to 34%) of gene replacement by homologous recombination. Finally, dTALENs caused no detectable cytotoxicity and minimal levels of undesired genetic mutations in the treated yeast strains. These studies expand the realm of verified TALEN activity from cultured human cells to an intact eukaryotic organism and suggest that low-cost, highly dependable dTALENs can assume a significant role for gene modifications of value in human and animal health, agriculture and industry.

  6. Modularly assembled designer TAL effector nucleases for targeted gene knockout and gene replacement in eukaryotes

    Energy Technology Data Exchange (ETDEWEB)

    Li, T; Huang, S; Zhao, XF; Wright, DA; Carpenter, S; Spalding, MH; Weeks, DP; Yang, B

    2011-08-08

    Recent studies indicate that the DNA recognition domain of transcription activator-like (TAL) effectors can be combined with the nuclease domain of FokI restriction enzyme to produce TAL effector nucleases (TALENs) that, in pairs, bind adjacent DNA target sites and produce double-strand breaks between the target sequences, stimulating non-homologous end-joining and homologous recombination. Here, we exploit the four prevalent TAL repeats and their DNA recognition cipher to develop a 'modular assembly' method for rapid production of designer TALENs (dTALENs) that recognize unique DNA sequence up to 23 bases in any gene. We have used this approach to engineer 10 dTALENs to target specific loci in native yeast chromosomal genes. All dTALENs produced high rates of site-specific gene disruptions and created strains with expected mutant phenotypes. Moreover, dTALENs stimulated high rates (up to 34%) of gene replacement by homologous recombination. Finally, dTALENs caused no detectable cytotoxicity and minimal levels of undesired genetic mutations in the treated yeast strains. These studies expand the realm of verified TALEN activity from cultured human cells to an intact eukaryotic organism and suggest that low-cost, highly dependable dTALENs can assume a significant role for gene modifications of value in human and animal health, agriculture and industry.

  7. Epithelial-specific knockout of the Rac1 gene leads to enamel defects.

    Science.gov (United States)

    Huang, Zhan; Kim, Jieun; Lacruz, Rodrigo S; Bringas, Pablo; Glogauer, Michael; Bromage, Timothy G; Kaartinen, Vesa M; Snead, Malcolm L

    2011-12-01

    The Ras-related C3 botulinum toxin substrate 1 (Rac1) gene encodes a 21-kDa GTP-binding protein belonging to the RAS superfamily. RAS members play important roles in controlling focal adhesion complex formation and cytoskeleton contraction, activities with consequences for cell growth, adhesion, migration, and differentiation. To examine the role(s) played by RAC1 protein in cell-matrix interactions and enamel matrix biomineralization, we used the Cre/loxP binary recombination system to characterize the expression of enamel matrix proteins and enamel formation in Rac1 knockout mice (Rac1(-/-)). Mating between mice bearing the floxed Rac1 allele and mice bearing a cytokeratin 14-Cre transgene generated mice in which Rac1 was absent from epithelial organs. Enamel of the Rac1 conditional knockout mouse was characterized by light microscopy, backscattered electron imaging in the scanning electron microscope, microcomputed tomography, and histochemistry. Enamel matrix protein expression was analyzed by western blotting. Major findings showed that the Tomes' processes of Rac1(-/-) ameloblasts lose contact with the forming enamel matrix in unerupted teeth, the amounts of amelogenin and ameloblastin are reduced in Rac1(-/-) ameloblasts, and after eruption, the enamel from Rac1(-/-) mice displays severe structural defects with a complete loss of enamel. These results support an essential role for RAC1 in the dental epithelium involving cell-matrix interactions and matrix biomineralization. © 2011 Eur J Oral Sci.

  8. CD38 gene knockout juvenile mice: a model of oxytocin signal defects in autism.

    Science.gov (United States)

    Higashida, Haruhiro; Yokoyama, Shigeru; Munesue, Toshio; Kikuchi, Mitsuru; Minabe, Yoshio; Lopatina, Olga

    2011-01-01

    Oxytocin (OXT) in the hypothalamus is the biological basis of social recognition, trust, and bonding. We showed that CD38, a leukaemia cell marker, plays an important role in the hypothalamus in the process of OXT release in adult mice. Disruption of Cd38 (Cd38(-/-)) produced impairment of maternal behavior and male social recognition in mice, similar to the behavior observed in Oxt and OXT receptor (Oxtr) gene knockout (Oxt(-/-) and Oxtr(-/-), respectively) mice. Locomotor activity induced by separation from the dam was higher and the number of ultrasonic vocalization (USV) calls was lower in Cd38(-/-) than Cd38(+/+) pups. These phenotypes seemed to be caused by the high plasma OXT levels during development from neonates to 3-week-old juvenile mice. ADP-ribosyl cyclase activity was markedly lower in the knockout mice from birth, suggesting that weaning for mice is a critical time window of differentiating plasma OXT. Contribution by breastfeeding was an important exogenous source for regulating plasma OXT before weaning by the presence of OXT in milk and the dam's mammary glands. The dissimilarity of Cd38(-/-) infant behaviour to Oxt(-/-) or Oxtr(-/-) mice can be explained partly by this exogenous source of OXT. These results suggest that secretion of OXT into the brain in a CD38-dependent manner may play an important role in the development of social behavior, and mice with OXT signalling deficiency, including Cd38(-/-), Oxt(-/-) and Oxtr(-/-) mice are good animal models for developmental disorders, such as autism.

  9. In Silico Knockout Studies of Xenophagic Capturing of Salmonella

    Science.gov (United States)

    Scheidel, Jennifer; Amstein, Leonie; Ackermann, Jörg; Dikic, Ivan; Koch, Ina

    2016-01-01

    The degradation of cytosol-invading pathogens by autophagy, a process known as xenophagy, is an important mechanism of the innate immune system. Inside the host, Salmonella Typhimurium invades epithelial cells and resides within a specialized intracellular compartment, the Salmonella-containing vacuole. A fraction of these bacteria does not persist inside the vacuole and enters the host cytosol. Salmonella Typhimurium that invades the host cytosol becomes a target of the autophagy machinery for degradation. The xenophagy pathway has recently been discovered, and the exact molecular processes are not entirely characterized. Complete kinetic data for each molecular process is not available, so far. We developed a mathematical model of the xenophagy pathway to investigate this key defense mechanism. In this paper, we present a Petri net model of Salmonella xenophagy in epithelial cells. The model is based on functional information derived from literature data. It comprises the molecular mechanism of galectin-8-dependent and ubiquitin-dependent autophagy, including regulatory processes, like nutrient-dependent regulation of autophagy and TBK1-dependent activation of the autophagy receptor, OPTN. To model the activation of TBK1, we proposed a new mechanism of TBK1 activation, suggesting a spatial and temporal regulation of this process. Using standard Petri net analysis techniques, we found basic functional modules, which describe different pathways of the autophagic capture of Salmonella and reflect the basic dynamics of the system. To verify the model, we performed in silico knockout experiments. We introduced a new concept of knockout analysis to systematically compute and visualize the results, using an in silico knockout matrix. The results of the in silico knockout analyses were consistent with published experimental results and provide a basis for future investigations of the Salmonella xenophagy pathway. PMID:27906974

  10. Studying Genes

    Science.gov (United States)

    ... NIGMS NIGMS Home > Science Education > Studying Genes Studying Genes Tagline (Optional) Middle/Main Content Area Other Fact Sheets What are genes? Genes are segments of DNA that contain instructions ...

  11. Identification of 9 uterine genes that are regulated during mouse pregnancy and exhibit abnormal levels in the cyclooxygenase-1 knockout mouse

    Directory of Open Access Journals (Sweden)

    Soper Jessica

    2007-07-01

    Full Text Available Abstract Background Preterm birth is the leading cause of all infant mortality. In 2004, 12.5% of all births were preterm. In order to understand preterm labor, we must first understand normal labor. Since many of the myometrial changes that occur during pregnancy are similar in mice and humans and mouse gestation is short, we have studied the uterine genes that change in the mouse during pregnancy. Here, we used microarray analysis to identify uterine genes in the gravid mouse that are differentially regulated in the cyclooxygenase-1 knockout mouse model of delayed parturition. Methods Gestational d18.0 uteri (n = 4 were collected from pregnant wild-type and cyclooxygenase-1 knockout mice. Part of the uterus was used for frozen sections and RNA was isolated from the remainder. Microarray analysis was performed at the Indiana University School of Medicine Genomic Core and analyzed using the Microarray Data Portal. Northern analysis was performed to confirm microarray data and the genes localized in the gravid uterus by in situ hybridization. Results We identified 277 genes that are abnormally expressed in the gravid d18.0 cyclooxygenase-1 knockout mouse. Nine of these genes are also regulated in the normal murine uterus during the last half of gestation. Many of these genes are involved in the immune response, consistent with an important role of the immune system in parturition. Expression of 4 of these genes; arginase I, IgJ, Tnfrsf9 and troponin; was confirmed by Northern analysis to be mis-regulated during pregnancy in the knockout mouse. In situ hybridization of these genes demonstrated a similar location in the gravid wild-type and Cox-1 knockout mouse uteri. Conclusion To our knowledge, this is the first work to demonstrate the uterine location of these 4 genes in the mouse during late pregnancy. There are several putative transcription factor binding sites that are shared by many of the 9 genes identified here including; estrogen and

  12. Rapid knockout and reporter mouse line generation and breeding colony establishment using EUCOMM conditional-ready embryonic stem cells: A case study

    Directory of Open Access Journals (Sweden)

    James L. J. Coleman

    2015-06-01

    Full Text Available As little as a decade ago, generation of a single knockout mouse line was an expensive and time-consuming undertaking available to relatively few researchers. The International Knockout Mouse Consortium, established in 2007, has revolutionized the use of such models by creating an open-access repository of ES cells that, through sequential breeding with first FlpE and then Cre recombinase transgenic mice, facilitates germline global or conditional deletion of almost every gene in the mouse genome. In this Case Study, we describe our experience using the repository to create mouse lines for a variety of experimental purposes. Specifically, we discuss the process of obtaining germline transmission of two EUCOMM ‘knockout-first’ gene targeted constructs and the advantages and pitfalls of using this system. We then outline our breeding strategy and the outcomes of our efforts to generate global and conditional knockouts and reporter mice for the genes of interest. Line maintenance, removal of recombinase transgenes and cryopreservation are also considered. Our approach led to the generation of heterozygous knockout mice within 6 months of commencing breeding to the founder mice. By describing our experiences with the EUCOMM ES cells and subsequent breeding steps, we hope to assist other researchers with the application of this valuable approach to generating versatile knockout mouse lines.

  13. Gamma aminobutyric acid transporter subtype 1 gene knockout mice: a new model for attention deficit/hyperactivity disorder

    Institute of Scientific and Technical Information of China (English)

    Ping Yang; Guoqiang Cai; Youqing Cai; Jian Fei; Guoxiang Liu

    2013-01-01

    Attention deficit/hyperactivity disorder (ADHD) is characterized by hyperactivity,impaired sustained attention,impulsivity,and is usually accompanied by varying degrees of learning difficulties and lack of motor coordination.However,the pathophysiology and etiology of ADHD remain inconclusive so far.Our previous studies have demonstrated that the gamma aminobutyric acid transporter subtype 1 (GAT1) gene knockout (ko) mouse (gat1-/-)is hyperactive and exhibited impaired memory performance in the Morris water maze.In the current study,we found that the gat1-/-mice showed low levels of attentional focusing and increased impulsivity.In addition,the gat1-/-mice displayed ataxia characterized by defects in motor coordination and balance skills.The hyperactivity in the ko mice was reduced by both methylphenidate and amphetamine.Collectively,these results suggest that GAT1 ko mouse is a new animal model for ADHD studying and GAT1 may be a new target to treat ADHD.

  14. Homeostasis of Retinol in Lecithin:retinol Acyltransferase Gene Knockout Mice Fed a High Retinol Diet

    OpenAIRE

    Liu, Limin; Tang, Xiao-Han; Gudas, Lorraine J.

    2008-01-01

    We analyzed the retinoid levels and gene expression in various tissues after wild type (Wt) and lecithin:retinol acyltransferase knockout (LRAT−/−) mice were fed a high retinol diet (250 IU/gram). As compared to Wt, LRAT−/− mice exhibited a greater and faster increase in serum retinol concentration (mean±S.D., Wt, 1.3±0.2 µM to 1.5±0.3 µM in 48 hours, p>0.05; LRAT−/−, 1.3±0.2 µM to 2.2±0.3 µM in 48 hours, p

  15. 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.

  16. Disease model discovery from 3,328 gene knockouts by The International Mouse Phenotyping Consortium.

    Science.gov (United States)

    Meehan, Terrence F; Conte, Nathalie; West, David B; Jacobsen, Julius O; Mason, Jeremy; Warren, Jonathan; Chen, Chao-Kung; Tudose, Ilinca; Relac, Mike; Matthews, Peter; Karp, Natasha; Santos, Luis; Fiegel, Tanja; Ring, Natalie; Westerberg, Henrik; Greenaway, Simon; Sneddon, Duncan; Morgan, Hugh; Codner, Gemma F; Stewart, Michelle E; Brown, James; Horner, Neil; Haendel, Melissa; Washington, Nicole; Mungall, Christopher J; Reynolds, Corey L; Gallegos, Juan; Gailus-Durner, Valerie; Sorg, Tania; Pavlovic, Guillaume; Bower, Lynette R; Moore, Mark; Morse, Iva; Gao, Xiang; Tocchini-Valentini, Glauco P; Obata, Yuichi; Cho, Soo Young; Seong, Je Kyung; Seavitt, John; Beaudet, Arthur L; Dickinson, Mary E; Herault, Yann; Wurst, Wolfgang; de Angelis, Martin Hrabe; Lloyd, K C Kent; Flenniken, Ann M; Nutter, Lauryl M J; Newbigging, Susan; McKerlie, Colin; Justice, Monica J; Murray, Stephen A; Svenson, Karen L; Braun, Robert E; White, Jacqueline K; Bradley, Allan; Flicek, Paul; Wells, Sara; Skarnes, William C; Adams, David J; Parkinson, Helen; Mallon, Ann-Marie; Brown, Steve D M; Smedley, Damian

    2017-08-01

    Although next-generation sequencing has revolutionized the ability to associate variants with human diseases, diagnostic rates and development of new therapies are still limited by a lack of knowledge of the functions and pathobiological mechanisms of most genes. To address this challenge, the International Mouse Phenotyping Consortium is creating a genome- and phenome-wide catalog of gene function by characterizing new knockout-mouse strains across diverse biological systems through a broad set of standardized phenotyping tests. All mice will be readily available to the biomedical community. Analyzing the first 3,328 genes identified models for 360 diseases, including the first models, to our knowledge, for type C Bernard-Soulier, Bardet-Biedl-5 and Gordon Holmes syndromes. 90% of our phenotype annotations were novel, providing functional evidence for 1,092 genes and candidates in genetically uncharacterized diseases including arrhythmogenic right ventricular dysplasia 3. Finally, we describe our role in variant functional validation with The 100,000 Genomes Project and others.

  17. Genetic background can result in a marked or minimal effect of gene knockout (GPR55 and CB2 receptor in experimental autoimmune encephalomyelitis models of multiple sclerosis.

    Directory of Open Access Journals (Sweden)

    Sofia Sisay

    Full Text Available Endocannabinoids and some phytocannabinoids bind to CB1 and CB2 cannabinoid receptors, transient receptor potential vanilloid one (TRPV1 receptor and the orphan G protein receptor fifty-five (GPR55. Studies using C57BL/10 and C57BL/6 (Cnr2 (tm1Zim CB2 cannabinoid receptor knockout mice have demonstrated an immune-augmenting effect in experimental autoimmune encephalomyelitis (EAE models of multiple sclerosis. However, other EAE studies in Biozzi ABH mice often failed to show any treatment effect of either CB2 receptor agonism or antagonism on inhibition of T cell autoimmunity. The influence of genetic background on the induction of EAE in endocannabinoid system-related gene knockout mice was examined. It was found that C57BL/6.GPR55 knockout mice developed less severe disease, notably in female mice, following active induction with myelin oligodendrocyte glycoprotein 35-55 peptide. In contrast C57BL/6.CB2 (Cnr2 (Dgen receptor knockout mice developed augmented severity of disease consistent with the genetically and pharmacologically-distinct, Cnr2 (tm1Zim mice. However, when the knockout gene was bred into the ABH mouse background and EAE induced with spinal cord autoantigens the immune-enhancing effect of CB2 receptor deletion was lost. Likewise CB1 receptor and transient receptor potential vanilloid one knockout mice on the ABH background demonstrated no alteration in immune-susceptibility, in terms of disease incidence and severity of EAE, in contrast to that reported in some C57BL/6 mouse studies. Furthermore the immune-modulating influence of GPR55 was marginal on the ABH mouse background. Whilst sedative doses of tetrahydrocannabinol could induce immunosuppression, this was associated with a CB1 receptor rather than a CB2 receptor-mediated effect. These data support the fact that non-psychoactive doses of medicinal cannabis have a marginal influence on the immune response in MS. Importantly, it adds a note of caution for the translational

  18. Highly efficient gene knockout by injection of TALEN mRNAs into oocytes and host transfer in Xenopus laevis.

    Science.gov (United States)

    Nakajima, Keisuke; Yaoita, Yoshio

    2015-01-16

    Zinc-finger nucleases, transcription activator-like effector nucleases (TALENs) and the CRISPR/Cas (clustered regularly interspaced short palindromic repeats/CRISPR-associated proteins) system are potentially powerful tools for producing tailor-made knockout animals. However, their mutagenic activity is not high enough to induce mutations at all loci of a target gene throughout an entire tadpole. In this study, we present a highly efficient method for introducing gene modifications at almost all target sequences in randomly selected embryos. The gene modification activity of TALEN is enhanced by adopting the host-transfer technique. In our method, the efficiency is further improved by injecting TALEN mRNAs fused to the 3'UTR of the Xenopus DEADSouth gene into oocytes, which are then transferred into a host female frog, where they are ovulated and fertilized. The addition of the 3'UTR of the DEADSouth gene promotes mRNA translation in the oocytes and increases the expression of TALEN proteins to near-maximal levels three hours post fertilization (hpf). In contrast, TALEN mRNAs without this 3'UTR are translated infrequently in oocytes. Our data suggest that genomic DNA is more sensitive to TALEN proteins from fertilization to the midblastula (MBT) stage. Our method works by increasing the levels of TALEN proteins during the pre-MBT stages.

  19. Highly efficient gene knockout by injection of TALEN mRNAs into oocytes and host transfer in Xenopus laevis

    Directory of Open Access Journals (Sweden)

    Keisuke Nakajima

    2015-01-01

    Full Text Available Zinc-finger nucleases, transcription activator-like effector nucleases (TALENs and the CRISPR/Cas (clustered regularly interspaced short palindromic repeats/CRISPR-associated proteins system are potentially powerful tools for producing tailor-made knockout animals. However, their mutagenic activity is not high enough to induce mutations at all loci of a target gene throughout an entire tadpole. In this study, we present a highly efficient method for introducing gene modifications at almost all target sequences in randomly selected embryos. The gene modification activity of TALEN is enhanced by adopting the host-transfer technique. In our method, the efficiency is further improved by injecting TALEN mRNAs fused to the 3′UTR of the Xenopus DEADSouth gene into oocytes, which are then transferred into a host female frog, where they are ovulated and fertilized. The addition of the 3′UTR of the DEADSouth gene promotes mRNA translation in the oocytes and increases the expression of TALEN proteins to near-maximal levels three hours post fertilization (hpf. In contrast, TALEN mRNAs without this 3′UTR are translated infrequently in oocytes. Our data suggest that genomic DNA is more sensitive to TALEN proteins from fertilization to the midblastula (MBT stage. Our method works by increasing the levels of TALEN proteins during the pre-MBT stages.

  20. The Knockout Mouse Project

    OpenAIRE

    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

    2004-01-01

    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 e...

  1. GRK5-Knockout Mice Generated by TALEN-Mediated Gene Targeting.

    Science.gov (United States)

    Nanjidsuren, Tsevelmaa; Park, Chae-Won; Sim, Bo-Woong; Kim, Sun-Uk; Chang, Kyu-Tae; Kang, Myung-Hwa; Min, Kwan-Sik

    2016-10-01

    Transcription activator-like effector nucleases (TALENs) are a new type of engineered nuclease that is very effective for directed gene disruption in any genome sequence. We investigated the generation of mice with genetic knockout (KO) of the G protein-coupled receptor kinase (GRK) 5 gene by microinjection of TALEN mRNA. TALEN vectors were designed to target exons 1, 3, and 5 of the mouse GRK5 gene. Flow cytometry showed that the activity of the TALEN mRNAs targeted to exons 1, 3, and 5 was 8.7%, 9.7%, and 12.7%, respectively. The TALEN mRNA for exon 5 was injected into the cytoplasm of 180 one-cell embryos. Of the 53 newborns, three (5.6%) were mutant founders (F0) with mutations. Two clones from F028 showed a 45-bp deletion and F039 showed the same biallelic non-frame-shifting 3-bp deletions. Three clones from F041 were shown to possess a combination of frame-shifting 2-bp deletions. All of the mutations were transmitted through the germline but not to all progenies (37.5%, 37.5%, and 57.1% for the F028, F039, and F041 lines, respectively). The homozygote GRK5-KO mice for 28 and 41 lines created on F3 progenies and the homozygous genotype was confirmed by PCR, T7E1 assay and sequencing.

  2. Improved generation of rat gene knockouts by target-selected mutagenesis in mismatch repair-deficient animals.

    NARCIS (Netherlands)

    van Boxtel, R.; Toonen, P.W.; Verheul, M.; van Roekel, H.S.; Nijman, I.J.; Guryev, V.; Cuppen, E.

    2008-01-01

    BACKGROUND: The laboratory rat (Rattus norvegicus) is one of the preferred model organisms in physiological and pharmacological research, although the availability of specific genetic models, especially gene knockouts, is limited. N-ethyl-N-nitrosourea (ENU)-driven target-selected mutagenesis is cur

  3. Improved generation of rat gene knockouts by target-selected mutagenesis in mismatch repair-deficient animals

    NARCIS (Netherlands)

    van Boxtel, Ruben; Toonen, Pim W; Verheul, Mark; van Roekel, Henk S; Nijman, Isaac J; Guryev, Victor; Cuppen, Edwin

    2008-01-01

    BACKGROUND: The laboratory rat (Rattus norvegicus) is one of the preferred model organisms in physiological and pharmacological research, although the availability of specific genetic models, especially gene knockouts, is limited. N-ethyl-N-nitrosourea (ENU)-driven target-selected mutagenesis is cur

  4. Enhanced morphine-induced antinociception in histamine H3 receptor gene knockout mice.

    Science.gov (United States)

    Mobarakeh, Jalal Izadi; Takahashi, Kazuhiro; Yanai, Kazuhiko

    2009-09-01

    Previous studies have implicated a potential role for histamine H3 receptor in pain processing. There have been conflicting data, however, on the roles of H3 receptors in pain perception, and little information is available about the role of spinal histamine H3 receptors in morphine-induced antinociception. In the present study we examined the role of histamine H3 receptor in morphine-induced antinociception using histamine H3 receptor knockout mice and a histamine H3 receptor antagonist. Anitinociception was evaluated by assays for four nociceptive stimuli: hot-plate, tail-flick, paw-withdrawal, and formalin tests. Antinociception induced by morphine (0.125 nmol/5 microl, i.t.) was significantly augmented in histamine H3 receptor knockout (-/-) mice compared to the wild-type (+/+) mice in all four assays of pain. Furthermore, the effect of intrathecally administered morphine with thioperamide, a histamine H3 antagonist, was examined in C57BL/6J mice. A low dose of i.t. administered thioperamide (0.125 nmol/5 microl) alone had no significant effect on the nociceptive response. In contrast, the combination of morphine (0.125 nmol/5 microl, i.t.) with the same dose of thioperamide resulted in a significant reduction in the pain-related behaviors in all four nociceptive tests. These results suggest that histamine exerts inhibitory effects on morphine-induced antinociception through H3 receptors at the spinal level.

  5. A Jacob/Nsmf Gene Knockout Results in Hippocampal Dysplasia and Impaired BDNF Signaling in Dendritogenesis.

    Directory of Open Access Journals (Sweden)

    Christina Spilker

    2016-03-01

    Full Text Available Jacob, the protein encoded by the Nsmf gene, is involved in synapto-nuclear signaling and docks an N-Methyl-D-Aspartate receptor (NMDAR-derived signalosome to nuclear target sites like the transcription factor cAMP-response-element-binding protein (CREB. Several reports indicate that mutations in NSMF are related to Kallmann syndrome (KS, a neurodevelopmental disorder characterized by idiopathic hypogonadotropic hypogonadism (IHH associated with anosmia or hyposmia. It has also been reported that a protein knockdown results in migration deficits of Gonadotropin-releasing hormone (GnRH positive neurons from the olfactory bulb to the hypothalamus during early neuronal development. Here we show that mice that are constitutively deficient for the Nsmf gene do not present phenotypic characteristics related to KS. Instead, these mice exhibit hippocampal dysplasia with a reduced number of synapses and simplification of dendrites, reduced hippocampal long-term potentiation (LTP at CA1 synapses and deficits in hippocampus-dependent learning. Brain-derived neurotrophic factor (BDNF activation of CREB-activated gene expression plays a documented role in hippocampal CA1 synapse and dendrite formation. We found that BDNF induces the nuclear translocation of Jacob in an NMDAR-dependent manner in early development, which results in increased phosphorylation of CREB and enhanced CREB-dependent Bdnf gene transcription. Nsmf knockout (ko mice show reduced hippocampal Bdnf mRNA and protein levels as well as reduced pCREB levels during dendritogenesis. Moreover, BDNF application can rescue the morphological deficits in hippocampal pyramidal neurons devoid of Jacob. Taken together, the data suggest that the absence of Jacob in early development interrupts a positive feedback loop between BDNF signaling, subsequent nuclear import of Jacob, activation of CREB and enhanced Bdnf gene transcription, ultimately leading to hippocampal dysplasia.

  6. Rapid-throughput skeletal phenotyping of 100 knockout mice identifies 9 new genes that determine bone strength.

    Directory of Open Access Journals (Sweden)

    J H Duncan Bassett

    Full Text Available Osteoporosis is a common polygenic disease and global healthcare priority but its genetic basis remains largely unknown. We report a high-throughput multi-parameter phenotype screen to identify functionally significant skeletal phenotypes in mice generated by the Wellcome Trust Sanger Institute Mouse Genetics Project and discover novel genes that may be involved in the pathogenesis of osteoporosis. The integrated use of primary phenotype data with quantitative x-ray microradiography, micro-computed tomography, statistical approaches and biomechanical testing in 100 unselected knockout mouse strains identified nine new genetic determinants of bone mass and strength. These nine new genes include five whose deletion results in low bone mass and four whose deletion results in high bone mass. None of the nine genes have been implicated previously in skeletal disorders and detailed analysis of the biomechanical consequences of their deletion revealed a novel functional classification of bone structure and strength. The organ-specific and disease-focused strategy described in this study can be applied to any biological system or tractable polygenic disease, thus providing a general basis to define gene function in a system-specific manner. Application of the approach to diseases affecting other physiological systems will help to realize the full potential of the International Mouse Phenotyping Consortium.

  7. Efficient bi-allelic gene knockout and site-specific knock-in mediated by TALENs in pigs.

    Science.gov (United States)

    Yao, Jing; Huang, Jiaojiao; Hai, Tang; Wang, Xianlong; Qin, Guosong; Zhang, Hongyong; Wu, Rong; Cao, Chunwei; Xi, Jianzhong Jeff; Yuan, Zengqiang; Zhao, Jianguo

    2014-11-05

    Pigs are ideal organ donors for xenotransplantation and an excellent model for studying human diseases, such as neurodegenerative disease. Transcription activator-like effector nucleases (TALENs) are used widely for gene targeting in various model animals. Here, we developed a strategy using TALENs to target the GGTA1, Parkin and DJ-1 genes in the porcine genome using Large White porcine fibroblast cells without any foreign gene integration. In total, 5% (2/40), 2.5% (2/80), and 22% (11/50) of the obtained colonies of fibroblast cells were mutated for GGTA1, Parkin, and DJ-1, respectively. Among these mutant colonies, over 1/3 were bi-allelic knockouts (KO), and no off-target cleavage was detected. We also successfully used single-strand oligodeoxynucleotides to introduce a short sequence into the DJ-1 locus. Mixed DJ-1 mutant colonies were used as donor cells for somatic cell nuclear transfer (SCNT), and three female piglets were obtained (two were bi-allelically mutated, and one was mono-allelically mutated). Western blot analysis showed that the expression of the DJ-1 protein was disrupted in KO piglets. These results imply that a combination of TALENs technology with SCNT can efficiently generate bi-allelic KO pigs without the integration of exogenous DNA. These DJ-1 KO pigs will provide valuable information for studying Parkinson's disease.

  8. Upregulated Expression of Cytotoxicity-Related Genes in IFN-γ Knockout Mice with Schistosoma japonicum Infection

    Directory of Open Access Journals (Sweden)

    Xiaotang Du

    2011-01-01

    Full Text Available It is well accepted that IFN-γ is important to the development of acquired resistance against murine schistosomiasis. However, the in vivo role of this immunoregulatory cytokine in helminth infection needs to be further investigated. In this study, parasite burden and host immune response were observed in IFN-γ knockout mice (IFNg KO infected with Schistosoma japonicum for 6 weeks. The results suggested that deficiency in IFN-γ led to decreased egg burden in mice, with low schistosome-specific IgG antibody response and enhanced activation of T cells during acute infection. Microarray and qRT-PCR data analyses showed significant upregulation of some cytotoxicity-related genes, including those from the granzyme family, tumor necrosis factor, Fas Ligand, and chemokines, in the spleen cells of IFNg KO mice. Furthermore, CD8+ cells instead of NK cells of IFNg KO mice exhibited increased transcription of cytotoxic genes compared with WT mice. Additionally, Schistosoma japonicum-specific egg antigen immunization also could activate CD8+ T cells to upregulate the expression of cytotoxic genes in IFNg KO mice. Our data suggest that IFN-γ is not always a positive regulator of immune responses. In certain situations, the disruption of IFN-γ signaling may up-regulate the cytotoxic T-cell-mediated immune responses to the parasite.

  9. Differential Expression of Genes Associated with the Progression of Renal Disease in the Kidneys of Liver-Specific Glucokinase Gene Knockout Mice

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    Gang Niu

    2013-03-01

    Full Text Available Liver glucokinase (GCK deficient mice possess mild renal complications associated with diabetes. To investigate the progression of kidney disease and identify candidate genes involved in the pathogenesis of renal damage, we examined changes in tissue structure and gene expression in the kidneys of liver-specific GCK knockout (gckw/− mice and age-matched normal wild-type control (gckw/w mice as they aged. Suppression subtractive hybridization (SSH was used to identify candidate genes that showed a pattern of differential expression between kidneys of gckw/− and gckw/w mice at 60 weeks of age. Differential expression of the candidate genes was examined by real-time qPCR in liver-specific gckw/− and gckw/w mice at 16, 26, 40, 60, and 85 weeks of age. Among the candidate genes, only glutathione peroxidase-3 (GPX3 was confirmed to show differential expression by qPCR in the 60-week old mice, however two others genes, MALAT1 and KEG, showed significant changes at other ages. This study shows that liver-specific glucokinase deficient mice display changes in kidney morphology by 40 weeks of age, and that renal complication may be correlated with a reduction in GPX3 levels. Since decreased GPX3 mRNA expression was observed at 26 weeks, which is younger than the age when pathological changes can be seen in kidney biopsies, GPX3 may serve as an early marker for kidney damage.

  10. Laser microdissection and microarray analysis of the hippocampus of Ras-GRF1 knockout mice reveals gene expression changes affecting signal transduction pathways related to memory and learning.

    Science.gov (United States)

    Fernández-Medarde, A; Porteros, A; de las Rivas, J; Núñez, A; Fuster, J J; Santos, E

    2007-04-25

    We used manual macrodissection or laser capture microdissection (LCM) to isolate tissue sections of the hippocampus area of Ras-GRF1 wild type and knockout mice brains, and analyzed their transcriptional patterns using commercial oligonucleotide microarrays. Comparison between the transcriptomes of macrodissected and microdissected samples showed that the LCM samples allowed detection of significantly higher numbers of differentially expressed genes, with higher statistical rates of significance. These results validate LCM as a reliable technique for in vivo genomic studies in the brain hippocampus, where contamination by surrounding areas (not expressing Ras-GRF1) increases background noise and impairs identification of differentially expressed genes. Comparison between wild type and knockout LCM hippocampus samples revealed that Ras-GRF1 elimination caused significant gene expression changes, mostly affecting signal transduction and related neural processes. The list of 36 most differentially expressed genes included loci concerned mainly with Ras/G protein signaling and cytoskeletal organization (i.e. 14-3-3gamma/zeta, Kcnj6, Clasp2) or related, cross-talking pathways (i.e. jag2, decorin, strap). Consistent with the phenotypes shown by Ras-GRF1 knockout mice, many of these differentially expressed genes play functional roles in processes such as sensory development and function (i.e. Sptlc1, antiquitin, jag2) and/or neurological development/neurodegeneration processes affecting memory and learning. Indeed, potential links to neurodegenerative diseases such as Alzheimer disease (AD) or Creutzfeldt-Jacobs disease (CJD), have been reported for a number of differentially expressed genes identified in this study (Ptma, Aebp2, Clasp2, Hebp1, 14-3-3gamma/zeta, Csnk1delta, etc.). These data, together with the previously described role of IRS and insulin (known Ras-GRF1 activators) in AD, warrant further investigation of a potential functional link of Ras-GRF1 to

  11. Establishment of IL-31 RA Gene Knockout Homozygous Mice Model%IL-31 RA基因敲除小鼠纯合子模型的建立

    Institute of Scientific and Technical Information of China (English)

    江涛; 高婧; 岳欢; 高雅倩; 黄俊琼

    2015-01-01

    目的:建立IL-31RA基因敲除小鼠纯合子模型,为IL-31RA基因相关研究提供动物模型。方法:IL-31RA基因敲除小鼠严格按照SPF级要求的动物饲养标准进行饲养繁殖,采用聚合酶链式反应( PCR)法鉴定子代小鼠的基因型,RT-PCR法鉴定小鼠IL-31RA mRNA的表达,Western blot鉴定IL-31RA蛋白的表达,HE染色观察小鼠重要脏器的形态学变化。结果:PCR法成功检测出子代小鼠的3种基因型,纯合子基因敲除小鼠未检测出IL-31RA mRNA和IL-31RA蛋白的表达,IL-31RA基因敲除小鼠的重要脏器的形态学特征与野生型小鼠比较无明显变化;基因敲除小鼠可成功饲养繁殖,亦可获得较多的基因敲除纯合子小鼠。结论:成功构建了IL-31RA基因敲除小鼠纯合子模型。%Objective:To establish the IL-31RA gene knockout homozygous mice model and lay the foundation for further study on IL-31 gene. Methods:IL-31RA gene knockout mice were bred and re-produced according to the SPF class animal feeding standard. PCR was used to identify the genotype of the offspring,the expression of IL-31RA mRNA was detected by RT-PCR,expression of IL-31RA pro-tein was detected by Western blot,and morphological changes of vital organs were observed by HE staining . Result:Three genotypes of the offspring of IL-31 RA gene knockout mice were successfully i-dentified;expression of IL-31 RA mRNA and IL-31 RA protein was not detected in IL-31 RA gene knockout homozygous mice. Compared with the wild type mice,morphological characteristics of vital organs of had no significant changes in IL-31RA gene knockout homozygous mice. IL-31RA gene knockout mice could be dred and reproduced successfully. Conclusion:The IL-31RA gene knockout homozygous mice model has been successfully established.

  12. Knockout of the TauT gene predisposes C57BL/6 mice to streptozotocin-induced diabetic nephropathy.

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    Xiaobin Han

    Full Text Available Diabetic nephropathy is the leading cause of end stage renal disease in the world. Although tremendous efforts have been made, scientists have yet to identify an ideal animal model that can reproduce the characteristics of human diabetic nephropathy. In this study, we hypothesize that taurine insufficiency is a critical risk factor for development of diabetic nephropathy associated with diabetes mellitus. This hypothesis was tested in vivo in TauT heterozygous (TauT+/- and homozygous (TauT-/- knockout in C57BL/6 background mice. We have shown that alteration of the TauT gene (also known as SLC6A6 has a substantial effect on the susceptibility to development of extensive diabetic kidney disease in both TauT+/- and TauT-/-mouse models of diabetes. These animals developed histological changes characteristic of human diabetic nephropathy that included glomerulosclerosis, nodular lesions, arteriosclerosis, arteriolar dilation, and tubulointerstitial fibrosis. Immunohistochemical staining of molecular markers of smooth muscle actin, CD34, Ki67 and collagen IV further confirmed these observations. Our results demonstrated that both homozygous and heterozygous TauT gene deletion predispose C57BL/6 mice to develop end-stage diabetic kidney disease, which closely replicates the pathological features of diabetic nephropathy in human diabetic patients.

  13. Knockout of the tumor necrosis factor α receptor 1 gene can up-regulate erythropoietin receptor during myocardial ischemia-reperfusion injury in mice

    Institute of Scientific and Technical Information of China (English)

    LI Chang-ling; JIANG Jun; FAN You-qi; FU Guo-sheng; WANG Jia-nan; FAN Wei-ming

    2009-01-01

    Background Tumor necrosis factor α receptor 1 (TNFαR1) plays an important role in the signal pathway of apoptosis.The objective of this study was to investigate the effects of TNFaR1 knockout on the up-regulation of erythropoietin receptor (Epo-R) and the coordinated anti-apoptosis functions during myocardial ischemia-reperfusion injury in mice.Methods The ischemia-reperfusion injury model for cardiomyocytes was performed by ligating the left circumflex branch artery of TNFαR1 knockout (P55-/-) C17 B6 mice, as well as wild-type (P55+/+) C17 B6 mice. Triphenyltetrazolium chloride (TTC) staining was performed to observe the damaged area of the heart. TUNEL staining and DNA fragmentation were used to identify apoptosis. Mitochondrial Bcl-2 and Bax as well as expression of Epo-R and its downstream genes (Jak-2, slat-5, Akt, IkB-α, HIF-1α) were measured by Western blotting. The gene knockout mice were assigned into those undergoing the apoptosis surgical model group (KO group), and those subjected to sham operation (Kos group). Similarly, wild-type mice were either exposed to the surgical model (WT group) or subject to a sham operation (WTs group).Results The myocardial damage ratio of the wild-type group after the operation was significantly higher than that of the knockout group, (50.5±6.4)% vs (36.9±6.9)%, P<0.01. Similarly, TUNEL positive ratio of the wild-type group was significantly higher than that of the knockout group, (63.1±5.6)% vs (42.1±4.7)%, P<0.01. The gray value ratios of Epo-R,Jak-2, stat-5, Akt, IkB-α, HIF-1 and mitochondrial Bcl-2 in the KO group were significantly higher than those of the WT group, P<0.05; however, mitochondrial Bax was significantly lower than that of the WT group significantly (P<0.05).Conclusions Using the ischemia-reperfusion injury model in mice, cardiomyocytes of TNFαR1 knockouts exhibited anti-apoptotic characteristics. This information could be used to coordinate the prevention of myocardial apoptosis by up

  14. Generation of Newly Discovered Resistance Gene mcr-1 Knockout in Escherichia coli Using the CRISPR/Cas9 System.

    Science.gov (United States)

    Sun, Lichang; He, Tao; Zhang, Lili; Pang, Maoda; Zhang, Qiaoyan; Zhou, Yan; Bao, Hongduo; Wang, Ran

    2017-07-28

    The mcr-1 gene is a new "superbug" gene discoverd in China in 2016 that makes bacteria highly resistant to the last-resort class of antibiotics. The mcr-1 gene raised serious concern about its possible global dissemination and spread. Here, we report a potential anti-resistant strategy using the CRISPR/Cas9-mediated approach that can efficiently induce mcr-1 gene knockout in Escherichia coli. Our findings suggested that using the CRISPR/Cas9 system to knock out the resistance gene mcr-1 might be a potential anti-resistant strategy. Bovine myeloid antimicrobial peptide-27 could help deliver plasmid pCas::mcr targeting specific DNA sequences of the mcr-1 gene into microbial populations.

  15. 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.

  16. Antinociceptive effects of morphine and naloxone in mu-opioid receptor knockout mice transfected with the MORS196A gene

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    Tao Pao-Luh

    2010-04-01

    Full Text Available Abstract Background Opioid analgesics such as morphine and meperidine have been used to control moderate to severe pain for many years. However, these opioids have many side effects, including the development of tolerance and dependence after long-term use, which has limited their clinical use. We previously reported that mutations in the mu-opioid receptors (MOR S196L and S196A rendered them responsive to the opioid antagonist naloxone without altering the agonist phenotype. In MORS196A knock-in mice, naloxone and naltrexone were antinociceptive but did not cause tolerance or physical dependence. In this study we delivery this mutated MOR gene into pain related pathway to confirm the possibility of in vivo transfecting MORS196A gene and using naloxone as a new analgesic agent. Methods The MOR-knockout (MOR-KO mice were used to investigate whether morphine and naloxone could show antinociceptive effects when MORS196A gene was transfected into the spinal cords of MOR-KO mice. Double-stranded adeno-associated virus type 2 (dsAAV2 was used to deliver the MORS196A-enhanced green fluorescence protein (EGFP gene by microinjected the virus into the spinal cord (S2/S3 dorsal horn region. Tail-flick test was used to measure the antinociceptive effect of drugs. Results Morphine (10 mg/kg, s.c. and naloxone (10 mg/kg, s.c. had no antinociceptive effects in MOR-KO mice before gene transfection. However, two or three weeks after the MOR-S196A gene had been injected locally into the spinal cord of MOR-KO mice, significant antinociceptive effects could be induced by naloxone or morphine. On the other hand, only morphine but not naloxone induced significant tolerance after sub-chronic treatment. Conclusion Transfecting the MORS196A gene into the spinal cord and systemically administering naloxone in MOR-KO mice activated the exogenously delivered mutant MOR and provided antinociceptive effect without causing tolerance. Since naloxone will not activate natural

  17. Disruption of seven hypothetical aryl alcohol dehydrogenase genes from Saccharomyces cerevisiae and construction of a multiple knock-out strain.

    Science.gov (United States)

    Delneri, D; Gardner, D C; Bruschi, C V; Oliver, S G

    1999-11-01

    By in silicio analysis, we have discovered that there are seven open reading frames (ORFs) in Saccharomyces cerevisiae whose protein products show a high degree of amino acid sequence similarity to the aryl alcohol dehydrogenase (AAD) of the lignin-degrading fungus Phanerochaete chrysosporium. Yeast cultures grown to stationary phase display a significant aryl alcohol dehydrogenase activity by degrading aromatic aldehydes to the corresponding alcohols. To study the biochemical and the biological role of each of the AAD genes, a series of mutant strains carrying deletion of one or more of the AAD-coding sequences was constructed by PCR-mediated gene replacement, using the readily selectable marker kanMX. The correct targeting of the PCR-generated disruption cassette into the genomic locus was verified by analytical PCR and by pulse-field gel electrophoresis (PFGE) followed by Southern blot analysis. Double, triple and quadruple mutant strains were obtained by classical genetic methods, while the construction of the quintuple, sextuple and septuple mutants was achieved by using the marker URA3 from Kluyveromyces lactis, HIS3 from Schizosaccharomyces pombe and TRP1 from S. cerevisiae. None of the knock-out strains revealed any mutant phenotype when tested for the degradation of aromatic aldehydes using both spectrophotometry and high performance liquid chromatography (HPLC). Specific tests for changes in the ergosterol and phospholipids profiles did not reveal any mutant phenotype and mating and sporulation efficiencies were not affected in the septuple deletant. Compared to the wild-type strain, the septuple deletant showed an increased resistance to the anisaldehyde, but there is a possibility that the nutritional markers used for gene replacement are causing this effect.

  18. Modeling and simulation of the main metabolism in Escherichia coli and its several single-gene knockout mutants with experimental verification

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    McFadden Johnjoe

    2010-11-01

    Full Text Available Abstract Background It is quite important to simulate the metabolic changes of a cell in response to the change in culture environment and/or specific gene knockouts particularly for the purpose of application in industry. If this could be done, the cell design can be made without conducting exhaustive experiments, and one can screen out the promising candidates, proceeded by experimental verification of a select few of particular interest. Although several models have so far been proposed, most of them focus on the specific metabolic pathways. It is preferred to model the whole of the main metabolic pathways in Escherichia coli, allowing for the estimation of energy generation and cell synthesis, based on intracellular fluxes and that may be used to characterize phenotypic growth. Results In the present study, we considered the simulation of the main metabolic pathways such as glycolysis, TCA cycle, pentose phosphate (PP pathway, and the anapleorotic pathways using enzymatic reaction models of E. coli. Once intracellular fluxes were computed by this model, the specific ATP production rate, the specific CO2 production rate, and the specific NADPH production rate could be estimated. The specific ATP production rate thus computed was used for the estimation of the specific growth rate. The CO2 production rate could be used to estimate cell yield, and the specific NADPH production rate could be used to determine the flux of the oxidative PP pathway. The batch and continuous cultivations were simulated where the changing patterns of extracellular and intra-cellular metabolite concentrations were compared with experimental data. Moreover, the effects of the knockout of such pathways as Ppc, Pck and Pyk on the metabolism were simulated. It was shown to be difficult for the cell to grow in Ppc mutant due to low concentration of OAA, while Pck mutant does not necessarily show this phenomenon. The slower growth rate of the Ppc mutant was properly

  19. CRISPR/Cas9 mediated chicken Stra8 gene knockout and inhibition of male germ cell differentiation

    Science.gov (United States)

    Zuo, Qisheng; Li, Dong; Zhang, Wenhui; Wang, Fei; Ji, Yanqin; Jin, Jing; Lu, Zhenyu; Wang, Man; Zhang, Chen; Li, Bichun

    2017-01-01

    An efficient genome editing approach had been established to construct the stable transgenic cell lines in the domestic chicken (Gallus gallus domesticus) at present. Our objectives were to investigate gene function in the differentiation process of chicken embryonic stem cells (ESCs) into spermatogonial stem cells(SSCs). Three guides RNA (gRNAs) were designed to knockout the Stra8 gene, and knockout efficiency was evaluated in domestic chicken cells using cleavage activity of in vitro transcription of gRNA, Luciferase-SSA assay, T7 endonuclease I assay(T7E1) and TA clone sequence. In addition, the Cas9/gRNA plasmid was transfected into ESCs to confirm the function of Stra8. SSA assay results showed that luciferase activity of the vector expressing gRNA-1 and gRNA- 2 was higher than that of gRNA-3. TA clone sequencing showed that the knockdown efficiency was 25% (10/40) in DF-1 cells, the knockdown efficiency was 23% (9/40) in chicken ESCs. T7E1 assay indicated that there were cleavage activity for three individuals, and the knockdown efficiency was 12% (3/25). Cell morphology, qRT-PCR, immunostaining and FCS indicated that Cas9/gRNA not only resulted in the knockout of Stra8 gene, but also suggested that the generation of SSCs was blocked by the Stra8 gene knockdown in vitro. Taken together, our results indicate that the CRISPR/Cas9 system could mediate stable Stra8 gene knockdown in domestic chicken’s cells and inhibit ECSs differentiation into SSCs. PMID:28234938

  20. Effects of SIRT1 gene knock-out via activation of SREBP2 protein-mediated PI3K/AKT signaling on osteoarthritis in mice.

    Science.gov (United States)

    Yu, Fei; Zeng, Hui; Lei, Ming; Xiao, De-Ming; Li, Wei; Yuan, Hao; Lin, Jian-Jing

    2016-10-01

    This study investigated the effects of SIRT1 gene knock-out on osteoarthritis in mice, and the possible roles of SREBP2 protein and the PI3K/AKT signaling pathway in the effects. Mice were randomly divided into a normal group and a SIRT1 gene knock-out group (6 mice in each group). In these groups, one side of the knee anterior cruciate ligament was traversed, and the ipsilateral medial meniscus was cut to establish an osteoarthritis model of knee joint. The countralateral synovial bursa was cut out, serving as controls. The knee joint specimens were then divided into four groups: SIRT1(+/+) control group (group A, n=6); SIRT1(+/+) osteoarthritis group (group B, n=6); SIRT1(-/-) control group (group C, n=6); SIRT1(-/-) osteoarthritis group (group D, n=6). HE staining, Masson staining, Safranin O-Fast Green staining and Van Gieson staining were used to observe the morphological changes in the articular cartilage of the knee. Immunohistochemical staining was employed to detect the expression of SIRT1, SREBP2, VEGF, AKT, HMGCR and type II collagen proteins. SA-β-gal staining was utilized to evaluate chondrocyte aging. The results showed clear knee joint cartilage destruction and degeneration in the SIRT1(-/-) osteoarthritis group. The tidal line was twisted and displaced anteriorly. Type II collagen was destroyed and distributed unevenly. Compared with the SIRT1(+/+) osteoarthritis group and SIRT1(-/-) control group, SIRT1 protein expression was not obviously changed in the SIRT1(-/-) osteoarthritis group (P>0.05), while the expression levels of the SREBP2, VEGF and HMGCR proteins were significantly increased (PSIRT1 gene knock-out may aggravate cartilage degeneration in osteoarthritis by activating the SREBP2 protein-mediated PI3K/AKT signalling pathway, suggesting that SIRT1 gene may play a protective role against osteoarthritis.

  1. Effects of alpha-AMPK knockout on exercise-induced gene activation in mouse skeletal muscle.

    Science.gov (United States)

    Jørgensen, Sebastian B; Wojtaszewski, Jørgen F P; Viollet, Benoit; Andreelli, Fabrizio; Birk, Jesper B; Hellsten, Ylva; Schjerling, Peter; Vaulont, Sophie; Neufer, P Darrell; Richter, Erik A; Pilegaard, Henriette

    2005-07-01

    We tested the hypothesis that 5'AMP-activated protein kinase (AMPK) plays an important role in regulating the acute, exercise-induced activation of metabolic genes in skeletal muscle, which were dissected from whole-body alpha2- and alpha1-AMPK knockout (KO) and wild-type (WT) mice at rest, after treadmill running (90 min), and in recovery. Running increased alpha1-AMPK kinase activity, phosphorylation (P) of AMPK, and acetyl-CoA carboxylase (ACC)beta in alpha2-WT and alpha2-KO muscles and increased alpha2-AMPK kinase activity in alpha2-WT. In alpha2-KO muscles, AMPK-P and ACCbeta-P were markedly lower compared with alpha2-WT. However, in alpha1-WT and alpha1-KO muscles, AMPK-P and ACCbeta-P levels were identical at rest and increased similarly during exercise in the two genotypes. The alpha2-KO decreased peroxisome-proliferator-activated receptor gamma coactivator (PGC)-1alpha, uncoupling protein-3 (UCP3), and hexokinase II (HKII) transcription at rest but did not affect exercise-induced transcription. Exercise increased the mRNA content of PGC-1alpha, Forkhead box class O (FOXO)1, HKII, and pyruvate dehydrogenase kinase 4 (PDK4) similarly in alpha2-WT and alpha2-KO mice, whereas glucose transporter GLUT 4, carnitine palmitoyltransferase 1 (CPTI), lipoprotein lipase, and UCP3 mRNA were unchanged by exercise in both genotypes. CPTI mRNA was lower in alpha2-KO muscles than in alpha2-WT muscles at all time-points. In alpha1-WT and alpha1-KO muscles, running increased the mRNA content of PGC-1alpha and FOXO1 similarly. The alpha2-KO was associated with lower muscle adenosine 5'-triphosphate content, and the inosine monophosphate content increased substantially at the end of exercise only in alpha2-KO muscles. In addition, subcutaneous injection of 5-aminoimidazole-4-carboxamide-1-beta-4-ribofuranoside (AICAR) increased the mRNA content of PGC-1alpha, HKII, FOXO1, PDK4, and UCP3, and alpha2-KO abolished the AICAR-induced increases in PGC-1alpha and HKII mRNA. In

  2. Improved generation of rat gene knockouts by target-selected mutagenesis in mismatch repair-deficient animals

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    van Roekel Henk S

    2008-10-01

    Full Text Available Abstract Background The laboratory rat (Rattus norvegicus is one of the preferred model organisms in physiological and pharmacological research, although the availability of specific genetic models, especially gene knockouts, is limited. N-ethyl-N-nitrosourea (ENU-driven target-selected mutagenesis is currently the most successful method in rats, although it is still very laborious and expensive. Results As ENU-induced DNA damage is normally recognized by the mismatch repair (MMR system, we hypothesized that the effectiveness of the target-selected mutagenesis approach could be improved by using a MMR-deficient genetic background. Indeed, Msh6 knockout rats were found to be more sensitive to ENU treatment and the germ line mutation rate was boosted more than two-fold to 1 mutation per 585 kb. In addition, the molecular mutation spectrum was found to be changed in favor of generating knockout-type alleles by ~20%, resulting in an overall increase in efficiency of ~2.5 fold. The improved effectiveness was demonstrated by high throughput mutation discovery in 70 Mb of sequence in a set of only 310 mutant F1 rats. This resulted in the identification of 89 mutations of which four introduced a premature stopcodon and 64 resulted in amino acid changes. Conclusion Taken together, we show that the use of a MMR-deficient background considerably improves ENU-driven target-selected mutagenesis in the rat, thereby reducing animal use as well as screening costs. The use of a mismatch repair-deficient genetic background for improving mutagenesis and target-selected knockout efficiency is in principle applicable to any organism of interest.

  3. Improved generation of rat gene knockouts by target-selected mutagenesis in mismatch repair-deficient animals

    Science.gov (United States)

    van Boxtel, Ruben; Toonen, Pim W; Verheul, Mark; van Roekel, Henk S; Nijman, Isaac J; Guryev, Victor; Cuppen, Edwin

    2008-01-01

    Background The laboratory rat (Rattus norvegicus) is one of the preferred model organisms in physiological and pharmacological research, although the availability of specific genetic models, especially gene knockouts, is limited. N-ethyl-N-nitrosourea (ENU)-driven target-selected mutagenesis is currently the most successful method in rats, although it is still very laborious and expensive. Results As ENU-induced DNA damage is normally recognized by the mismatch repair (MMR) system, we hypothesized that the effectiveness of the target-selected mutagenesis approach could be improved by using a MMR-deficient genetic background. Indeed, Msh6 knockout rats were found to be more sensitive to ENU treatment and the germ line mutation rate was boosted more than two-fold to 1 mutation per 585 kb. In addition, the molecular mutation spectrum was found to be changed in favor of generating knockout-type alleles by ~20%, resulting in an overall increase in efficiency of ~2.5 fold. The improved effectiveness was demonstrated by high throughput mutation discovery in 70 Mb of sequence in a set of only 310 mutant F1 rats. This resulted in the identification of 89 mutations of which four introduced a premature stopcodon and 64 resulted in amino acid changes. Conclusion Taken together, we show that the use of a MMR-deficient background considerably improves ENU-driven target-selected mutagenesis in the rat, thereby reducing animal use as well as screening costs. The use of a mismatch repair-deficient genetic background for improving mutagenesis and target-selected knockout efficiency is in principle applicable to any organism of interest. PMID:18840264

  4. Dopamine, kidney, and hypertension: studies in dopamine receptor knockout mice

    OpenAIRE

    Wang, Xiaoyan; Villar, Van Anthony M.; Armando, Ines; Eisner, Gilbert M.; Felder, Robin A.; Pedro A. Jose

    2008-01-01

    Dopamine is important in the pathogenesis of hypertension because of abnormalities in receptor-mediated regulation of renal sodium transport. Dopamine receptors are classified into D1-like (D1, D5) and D2-like (D2, D3, D4) subtypes, all of which are expressed in the kidney. Mice deficient in specific dopamine receptors have been generated to provide holistic assessment on the varying physiological roles of each receptor subtype. This review examines recent studies on these mutant mouse models...

  5. Fatty Liver and Insulin Resistance in the Liver-Specific Knockout Mice of Mitogen Inducible Gene-6

    Science.gov (United States)

    Park, Byung Kil; Kim, Hee-Youn; Lee, Jun Choul; Kim, Koon Soon; Jeong, Won Hoon; Kim, Ki Young

    2016-01-01

    Mitogen inducible gene-6 (Mig-6) is a feedback inhibitor of epidermal growth factor receptor (EGFR) signaling pathway. The liver-specific knockout mice of the Mig-6 gene (Mig-6d/d) showed hepatomegaly and increased hypercholesterolemia. In this study, the biomarkers of insulin resistance and the effects of high-fat diets in the wild (Mig-6f/f) and Mig-6d/d mice were analyzed. The fasting plasma concentrations of glucose, triglyceride, cholesterols, free fatty acids, and HOMA-IR were measured and the glucose tolerance and insulin resistance tests were performed in the 25-week-old Mig-6f/f and the Mig-6d/d mice. The protein levels of active insulin receptor, glucose 6-phosphatase, and phosphoenolpyruvate carboxykinase were analyzed in the liver and fat. The fasting plasma cholesterol and glucose concentration were higher in the Mig-6d/d mice than the Mig-6f/f mice with increased fat deposition in the liver. But the Mig-6d/d mice had the improved glucose intolerance and insulin resistance without increased amount of phosphoinsulin receptor after insulin infusion in the liver. The hepatic concentration of phosphoenolpyruvate carboxykinase was increased in fasting Mig-6d/d mice. The feeding of high-fat diet accelerated the plasma lipids profiles and HOMA-IR in the Mig-6d/d mice but had no differential effects in oral glucose tolerance test and insulin tolerance test in both genotypes. These results suggest that the activated EGFR signaling might increase the fasting plasma glucose concentration through inducing the hepatic steatosis and the improved whole-body insulin resistance in the KO mice be caused by decreased adipogenesis in fat tissues. PMID:28053990

  6. Dopamine, kidney, and hypertension: studies in dopamine receptor knockout mice.

    Science.gov (United States)

    Wang, Xiaoyan; Villar, Van Anthony M; Armando, Ines; Eisner, Gilbert M; Felder, Robin A; Jose, Pedro A

    2008-12-01

    Dopamine is important in the pathogenesis of hypertension because of abnormalities in receptor-mediated regulation of renal sodium transport. Dopamine receptors are classified into D(1)-like (D(1), D(5)) and D(2)-like (D(2), D(3), D(4)) subtypes, all of which are expressed in the kidney. Mice deficient in specific dopamine receptors have been generated to provide holistic assessment on the varying physiological roles of each receptor subtype. This review examines recent studies on these mutant mouse models and evaluates the impact of individual dopamine receptor subtypes on blood pressure regulation.

  7. Deep Brain Photoreceptor (val-opsin) Gene Knockout Using CRISPR/Cas Affects Chorion Formation and Embryonic Hatching in the Zebrafish

    Science.gov (United States)

    Hang, Chong Yee; Moriya, Shogo; Ogawa, Satoshi; Parhar, Ishwar S.

    2016-01-01

    Non-rod non-cone photopigments in the eyes and the brain can directly mediate non-visual functions of light in non-mammals. This was supported by our recent findings on vertebrate ancient long (VAL)-opsin photopigments encoded by the val-opsinA (valopa) and val-opsinB (valopb) genes in zebrafish. However, the physiological functions of valop isoforms remain unknown. Here, we generated valop-mutant zebrafish using CRISPR/Cas genome editing, and examined the phenotypes of loss-of-function mutants. F0 mosaic mutations and germline transmission were confirmed via targeted insertions and/or deletions in the valopa or valopb gene in F1 mutants. Based on in silico analysis, frameshift mutations converted VAL-opsin proteins to non-functional truncated forms with pre-mature stop codons. Most F1 eggs or embryos from F0 female valopa/b mutants showed either no or only partial chorion elevation, and the eggs or embryos died within 26 hour-post-fertilization. However, most F1 embryos from F0 male valopa mutant developed but hatched late compared to wild-type embryos, which hatched at 4 day-post-fertilization. Late-hatched F1 offspring included wild-type and mutants, indicating the parental effects of valop knockout. This study shows valop gene knockout affects chorion formation and embryonic hatching in the zebrafish. PMID:27792783

  8. A homozygous Keap1-knockout human embryonic stem cell line generated using CRISPR/Cas9 mediates gene targeting

    Directory of Open Access Journals (Sweden)

    So-Jung Kim

    2017-03-01

    Full Text Available Kelch-like ECH-associated protein 1 (keap1 is a cysteine-rich protein that interacts with transcription factor Nrf2 in a redox-sensitive manner, leading to the degradation of Nrf2 (Kim et al., 2014a. Disruption of Keap1 results in the induction of Nrf2-related signaling pathways involving the expression of a set of anti-oxidant and anti-inflammatory genes. We generated biallelic mutants of the Keap1 gene using a CRISPR-Cas9 genome editing method in the H9 human embryonic stem cell (hESC. The Keap1 homozygous-knockout H9 cell line retained normal morphology, gene expression, and in vivo differentiation potential.

  9. 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.

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

    Science.gov (United States)

    Karp, Natasha A; Speak, Anneliese O; White, Jacqueline K; Adams, David J; Hrabé de Angelis, Martin; Hérault, Yann; Mott, Richard F

    2014-01-01

    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.

  11. TNF-α Gene Knockout in Triple Negative Breast Cancer Cell Line Induces Apoptosis

    Directory of Open Access Journals (Sweden)

    Valentina Pileczki

    2012-12-01

    Full Text Available Tumor necrosis factor alpha (TNF-α is a pro-inflammatory cytokine involved in the promotion and progression of cancer, including triple negative breast cancer cells. Thus, there is significant interest in understanding the molecular signaling pathways that connect TNF-α with the survival of tumor cells. In our experiments, we used as an in vitro model for triple negative breast cancer the cell line Hs578T. The purpose of this study is to determine the gene expression profiling of apoptotic signaling networks after blocking TNF-α formation by using specially designed siRNA molecules to target TNF-α messenger RNA. Knockdown of TNF-α gene was associated with cell proliferation inhibition and apoptosis, as observed by monitoring the cell index using the xCELLigence RTCA System and flow cytometry. PCR array technology was used to examine the transcript levels of 84 genes involved in apoptosis. 15 genes were found to be relevant after comparing the treated group with the untreated one of which 3 were down-regulated and 12 up-regulated. The down-regulated genes are all involved in cell survival, whereas the up-regulated ones are involved in and interact with pro-apoptotic pathways. The results described here indicate that the direct target of TNF-α in the Hs578T breast cancer cell line increases the level of certain pro-apoptotic factors that modulate different cellular networks that direct the cells towards death.

  12. Generation and confirmation of NAAG peptidase gene knockout model%NAAG肽酶基因剔除小鼠模型的建立及鉴定

    Institute of Scientific and Technical Information of China (English)

    崔振文; 张明坤; 钟春龙; 吴增宝; 蔡蕾; 匡颖; 王铸钢; 江基尧; 罗其中

    2012-01-01

    目的 建立N-乙酰天冬氨酰谷氨酸(NAAG)肽酶基因剔除小鼠模型,为在体研究NAAG肽酶基因的生物学功能并揭示其在脑损伤后继发性脑损害进程中的所起的作用创造条件.方法 根据小鼠NAAG肽酶基因组的序列,设计基因剔除策略,构建基因剔除载体NAAG-KO-pBR322,以电穿孔方法将基因剔除载体导入胚胎干细胞(ES),应用G418和更昔洛韦进行正负筛选,获得双抗性克隆,聚合酶链式反应(PCR)鉴定并测序获得正确同源重组的ES细胞克隆.结果 同源重组的ES细胞注入小鼠囊胚后获得11只嵌合率>50%嵌合体雄性小鼠,嵌合体小鼠与C57 BL/6J雌鼠交配后获得11只杂合子小鼠,其中雄性7只,雌性4只.在雌、雄杂合子小鼠交配的后代中获得7只纯合子小鼠,PCR鉴定其基因型,逆转录PCR (RT-PCR)提示该基因鼠未表达NAAG肽酶.结论 我们成功建立了NAAG肽酶基因剔除小鼠模型,其中纯合子小鼠未出现胚胎致死现象;初步的表型观察未发现NAAG肽酶基因剔除小鼠出现异常改变.%Objective To establish N-acetylaspartylglutamate (NAAG) peptidase gene knockout mouse model and to create the condition for farther in vivo study of its biological function and its role in the secondary brain damage after brain injury. Methods According to the NAAG peptidase genomic DNA sequence ,the strategy of gene targeting was established, and the gene knockout vector (NAAG-KO-pBR322) was constructed. Electroporation of embryonic stem (ES) cells with the gene knockout vector and screening of both G418 and Ganciclovir resistant clones were performed. The homologous recombined ES ceD clones were identified by polymerase chain reaction (PCR). Results After transplantation of homologous recombined ES cells into blastocysts through microinjection, there were 11 male chimeras bom with embedment rate >50%. The male chimeras then were bred with C57BL/6J female mice and 7(♂) and 4 (♀) offsprings with

  13. Breeding and Genotyping of PTA-1-/-/ApoE-/-Double-gene Knockout Mice%PTA-1-/-/ApoE-/-双基因敲除小鼠的繁育及基因型鉴定

    Institute of Scientific and Technical Information of China (English)

    董子龙; 庄然; 张宇丝; 金伯泉; 张圆

    2012-01-01

    目的 建立(PTA-1-/-/ApoE-/-)双基因敲除小鼠(double-gene knockout,DKO)模型,探讨该小鼠的繁育及鉴定方法,为进一步利用该小鼠研究相关疾病奠定基础.方法 将引进的PTA-1-/-及ApoE-/-基因敲除小鼠通过杂交和互交的方法进行繁殖,以得到DKO小鼠.结果 经过PCR基因鉴定的方法证实PTA-1-/-/ApoE-/-双基因敲除小鼠繁育成功.结论 正确的饲养繁殖及鉴定方法是获得该DKO纯合子小鼠的有效途径.%Objective To breed and identify the PTA-1-/-/ApoE-/- double-gene knockout (DKO) mice and to establish an animal model to further study the role of PTA-1 molecule in diseases. Method PTA-1 gene knockout mice were paired with the ApoE gene knockout mice in different ways. Genomic DNA were isolated from the tails and analyzed by PCR. Result Genotyping analysis identified that we established PTA-1 -/-/ApoE-/- DKO mice successfully. Conclusion It is feasible to breed PTA-1 -/-/ApoE-/- DKO mice with the PTA-1 and ApoE gene knockout mice. PCR can be used to identify the genotype of the DKO mice precisely.

  14. Pathogenicty and immune prophylaxis of cag pathogenicity island gene knockout homogenic mutants

    Institute of Scientific and Technical Information of China (English)

    Huan-Jian Lin; Jing Xue; Yang Bai; Ji-De Wang; Ya-Li Zhang; Dian-Yuan Zhou

    2004-01-01

    AIM: To clarify the role of cag pathogenicity island (cagPAI)of Helicobacter pylori(H pylori) in the pathogenicity and immune prophylaxis of H pyloriinfection.METHODS: Three pairs of H pylori including 3 strains of cagPAI positive wildtype bacteria and their cagPAI knockout homogenic mutants were utilized. H pylori binding to the gastric epithelial cells was analyzed by flow cytometry assays.Apoptosis of gastric epithelial cells induced by H pylori was determined by ELISA assay. Prophylaxis effect of the wildtype and mutant strains was compared by immunization with the sonicate of the bacteria into mice model.RESULTS: No difference was found in the apoptasis between cagPAI positive and knockout H pylori strains in respective of the ability in the binding to gastric epithelial cells as well as the induction of apoptosis. Both types of the bacteria were able to protect the mice from the infection of H pylori after immunization, with no difference between them regarding to the protection rate as well as the stimulation of the proliferation of splenocytes of the mice.CONCLUSION: The role of cagPAI in the pathogenicity and prophylaxis of H pylori infection remains to be cleared.

  15. SETD4基因敲除小鼠的构建及鉴定%Establishment and Identification of SETD4gene knockout mice

    Institute of Scientific and Technical Information of China (English)

    黄穗; 黄梦怡; 钟玙沄; 雷烨铭; 赵舒祺; 蔡军伟; 姜勇; 刘靖华

    2016-01-01

    Objective To study the function of SETD4,the SETD4 gene knockout homozygous mice has been established. Methods SETD4flox/+mice and EIIa-Cre mice were interbred,the offspring of which was genotyping SETD4 +/-.EIIa-Cre were crossed with C57BL/6 mice to obtain the mice with the SETD4+/-genotype,SETD4+/-heterozygous mice were inbred and then the SETD4-/- homozygous mice were gained. PCR was used to identify the genotype of the offspring,the expression of SETD4 mRNA was detected by RT-PCR and qPCR,and morphological changes of liver and lung were observed by HE staining. Result PCR results showed genotypes of the offspring of SETD4 gene knockout mice was in accordance with SETD4-/-. Compared with the wild type mice,expression of SETD4 mRNA in SETD4 gene knockout homozygous mice was significantly decreased,and morphological characteristics of liver and lung in SETD4 gene knockout homozygous mice had no significant changes. Conclusion Wehave successfully generated SETD4 gene knockout homozygous mice which can be used for study ofSETD4 function.%目的:构建并鉴定SETD4基因敲除小鼠,为研究SETD4的生物学功能提供动物模型。方法将引进的SETD4flox/+小鼠与EIIa-Cre小鼠进行杂交繁殖,得到基因型为SETD4+/-.EIIa-Cre的小鼠;再与C57BL/6小鼠杂交去除Cre酶,获得杂合子SETD4+/-小鼠;该小鼠自交获得纯合子SETD4-/-小鼠。通过PCR法鉴定子代小鼠的基因型;RT-PCR、荧光定量PCR方法鉴定纯合子的SETD4基因敲除小鼠SETD4 mRNA表达情况;HE染色观察小鼠肝、肺组织的形态学变化。结果 PCR结果表明子代小鼠的基因型符合SETD4-/-;纯合子基因敲除小鼠SETD4 mRNA水平显著低于野生型小鼠;SETD4基因敲除小鼠肝、肺组织的形态学特征与野生型小鼠相比无明显差异。结论本研究基于Cre/loxp系统,成功构建并鉴定了SETD4基因敲除小鼠。

  16. Neuroanatomy of the fragile X knockout mouse brain studied using in vivo high resolution magnetic resonance imaging

    National Research Council Canada - National Science Library

    Kooy, R F; Reyniers, E; Verhoye, M; Sijbers, J; Bakker, C E; Oostra, B A; Willems, P J; Van Der Linden, A

    1999-01-01

    ..., the hippocampus, and the ventricular system. We intended to quantify the differences observed in the patient studies in the fragile X knockout mouse model, which is a good model for the disease, paralleling the human disorder in having...

  17. Generation of biallelic knock-out sheep via gene-editing and somatic cell nuclear transfer.

    Science.gov (United States)

    Li, Honghui; Wang, Gui; Hao, Zhiqiang; Zhang, Guozhong; Qing, Yubo; Liu, Shuanghui; Qing, Lili; Pan, Weirong; Chen, Lei; Liu, Guichun; Zhao, Ruoping; Jia, Baoyu; Zeng, Luyao; Guo, Jianxiong; Zhao, Lixiao; Zhao, Heng; Lv, Chaoxiang; Xu, Kaixiang; Cheng, Wenmin; Li, Hushan; Zhao, Hong-Ye; Wang, Wen; Wei, Hong-Jiang

    2016-09-22

    Transgenic sheep can be used to achieve genetic improvements in breeds and as an important large-animal model for biomedical research. In this study, we generated a TALEN plasmid specific for ovine MSTN and transfected it into fetal fibroblast cells of STH sheep. MSTN biallelic-KO somatic cells were selected as nuclear donor cells for SCNT. In total, cloned embryos were transferred into 37 recipient gilts, 28 (75.7%) becoming pregnant and 15 delivering, resulting in 23 lambs, 12 of which were alive. Mutations in the lambs were verified via sequencing and T7EI assay, and the gene mutation site was consistent with that in the donor cells. Off-target analysis was performed, and no off-target mutations were detected. MSTN KO affected the mRNA expression of MSTN relative genes. The growth curve for the resulting sheep suggested that MSTN KO caused a remarkable increase in body weight compared with those of wild-type sheep. Histological analyses revealed that MSTN KO resulted in muscle fiber hypertrophy. These findings demonstrate the successful generation of MSTN biallelic-KO STH sheep via gene editing in somatic cells using TALEN technology and SCNT. These MSTN mutant sheep developed and grew normally, and exhibited increased body weight and muscle growth.

  18. malT knockout mutation invokes a stringent type gene-expression profile in Actinobacillus pleuropneumoniae in bronchoalveolar fluid

    Directory of Open Access Journals (Sweden)

    Nash John HE

    2009-09-01

    Full Text Available Abstract Background Actinobacillus pleuropneumoniae causes contagious pleuropneumonia, an economically important disease of commercially reared pigs throughout the world. To cause this disease, A. pleuropneumoniae must rapidly overcome porcine pulmonary innate immune defenses. Since bronchoalveolar fluid (BALF contains many of the innate immune and other components found in the lungs, we examined the gene expression of a virulent serovar 1 strain of A. pleuropneumoniae after exposure to concentrated BALF for 30 min. Results In reverse transcription PCR differential display (RT-PCR DD experiments, A. pleuropneumoniae CM5 exposed to BALF up-regulated, among other genes, a gene predicted to encode LamB, an outer-membrane transport protein of the maltose regulon. To determine the role of the lamB and other genes of the maltose regulon in the pathogenesis of A. pleuropneumoniae, knockout mutations were created in the lamB and malT genes, the latter being the positive transcriptional regulator of the maltose regulon. Relative to the lamB mutant and the wild type, the malT mutant had a significant (P malT mutant exhibited a gene-expression profile resembling that of a stringent type gene-expression profile seen in bacteria facing amino acid or carbon starvation. Genes encoding proteins for protein synthesis, energy metabolism, and DNA replication were down-regulated, while genes involved in stringent response (e.g., relA, amino acid and nucleotide biosynthesis, biofilm formation, DNA transformation, and stress response were up-regulated. Conclusion These results suggest that MalT may be involved in protection against some stressors and in the transport of one or more essential nutrients in BALF. Moreover, if MalT is directly or indirectly linked to the stringent response, an important global mechanism of bacterial persistence and virulence in many bacterial pathogens, it might play a role in A. pleuropneumoniae pathogenesis.

  19. Reconstructing gene regulatory networks from knock-out data using Gaussian Noise Model and Pearson Correlation Coefficient.

    Science.gov (United States)

    Mohamed Salleh, Faridah Hani; Arif, Shereena Mohd; Zainudin, Suhaila; Firdaus-Raih, Mohd

    2015-12-01

    A gene regulatory network (GRN) is a large and complex network consisting of interacting elements that, over time, affect each other's state. The dynamics of complex gene regulatory processes are difficult to understand using intuitive approaches alone. To overcome this problem, we propose an algorithm for inferring the regulatory interactions from knock-out data using a Gaussian model combines with Pearson Correlation Coefficient (PCC). There are several problems relating to GRN construction that have been outlined in this paper. We demonstrated the ability of our proposed method to (1) predict the presence of regulatory interactions between genes, (2) their directionality and (3) their states (activation or suppression). The algorithm was applied to network sizes of 10 and 50 genes from DREAM3 datasets and network sizes of 10 from DREAM4 datasets. The predicted networks were evaluated based on AUROC and AUPR. We discovered that high false positive values were generated by our GRN prediction methods because the indirect regulations have been wrongly predicted as true relationships. We achieved satisfactory results as the majority of sub-networks achieved AUROC values above 0.5.

  20. Orexin gene transfer into the amygdala suppresses both spontaneous and emotion-induced cataplexy in orexin-knockout mice.

    Science.gov (United States)

    Liu, Meng; Blanco-Centurion, Carlos; Konadhode, Roda Rani; Luan, Liju; Shiromani, Priyattam J

    2016-03-01

    Narcolepsy is a chronic sleep disorder linked to the loss of orexin-producing neurons in the hypothalamus. Cataplexy, a sudden loss of muscle tone during waking, is an important distinguishing symptom of narcolepsy and it is often triggered by strong emotions. The neural circuit underlying cataplexy attacks is not known, but is likely to involve the amygdala, a region implicated in regulating emotions. In mice models of narcolepsy, transfer of the orexin gene into surrogate neurons has been successful in ameliorating narcoleptic symptoms. However, it is not known whether this method also blocks cataplexy triggered by strong emotions. To examine this possibility, the gene encoding mouse prepro-orexin was transferred into amygdala neurons of orexin-knockout (KO) mice (rAAV-orexin; n = 8). Orexin-KO mice that did not receive gene transfer (no-rAAV; n = 7) or received only the reporter gene (rAAV-GFP; n = 7) served as controls. Three weeks later, the animal's sleep and behaviour were recorded at night (no-odour control night), followed by another recording at night in the presence of predator odour (odour night). Orexin-KO mice given the orexin gene transfer into surrogate amygdala neurons had significantly less spontaneous bouts of cataplexy, and predator odour did not induce cataplexy compared with control mice. Moreover, the mice with orexin gene transfer were awake more during the odour night. These results demonstrate that orexin gene transfer into amygdala neurons can suppress both spontaneous and emotion-induced cataplexy attacks in narcoleptic mice. It suggests that manipulating amygdala pathways is a potential strategy for treating cataplexy in narcolepsy.

  1. [Biological characteristics of an Hog1 MAPK homologous gene FoHog1 knock-out mutant of Fusarium oxysporum f. sp. cubense].

    Science.gov (United States)

    Mao, Chao; Chen, Pingya; Dai, Qingdong; Yang, Laying; Huang, Junsheng

    2014-11-04

    This study was aimed to obtain a mitogen-activated protein kinase (MAPK) gene namely FoHog1 from Fusarium oxysporum f. sp. cubense and to verify its function. We amplified FoHog1 gene by PCR and RT-PCR methods and analyzed it through bioinformatics method. PEG-mediated protoplast transformation was used to create the deletion mutants of FoHog1 gene. We analyzed different biological characteristics between knock-out strain and wild-type strain. FoHog1 gene encoding a putative protein of 357 amino acids and its genetic relationship with different Fusarium' s protein. Compared with the wild-type strain, FoHog1 deletion mutants have loose hyphae colony, less spores production, lower dry weight of hyphae and more sensitive to temperature, pH and osmotic stress. FoHog1 deletion mutants also have reduced colonization ability compared with the wild-type strain. FoHog1 gene participated in mycelial growth, sporulation, catabolism of sodium acetate and ammonium chloride, osmotic stress response and pathogenic process with Fusarium oxysporum f. sp. cubense Race 4.

  2. Brain metabolic markers reflect susceptibility status in cytokine gene knockout mice with murine cerebral malaria.

    Science.gov (United States)

    Parekh, Sapan B; Bubb, William A; Hunt, Nicholas H; Rae, Caroline

    2006-11-01

    Treatment of cerebral malaria, a complication of the world's most significant parasitic disease, remains problematic due to lack of understanding of its pathogenesis. Metabolic changes, along with cytokine expression alterations and blood cell sequestration in the brain, have previously been reported during severe disease in human infection and mouse models leading to the "cytopathic hypoxia" and "sequestration" theories of pathogenesis. Here, to determine the robustness of the metabolic changes and their relationship to disease development, we investigated changes in cerebral metabolic markers in a mouse model of cerebral malaria (CM) in wildtype (C57BL/6) and cytokine knockout (TNF(-/-), IFNgamma(-/-) and LTalpha(-/-)) mice using multinuclear magnetic resonance spectroscopy. Mice susceptible to CM (wildtype, TNF(-/-)) showed decreased cerebral glucose use, decreased Krebs cycle metabolism and decreased high-energy phosphates. Conversely, mice resistant to CM (IFNgamma(-/-), LTalpha(-/-)) showed little sign of these effects, despite identical levels of parasitemia. Previously reported changes in lactate were shown to be strain dependent. Elevated glutamine and decreased phosphorylation potential emerged as robust metabolic markers of susceptibility, further implicating the trytophan/NAD(+) pathway in disease development. Thus these metabolic changes are firmly linked both to the immune system response to malaria and to the occurrence of pathogenic changes in experimental CM.

  3. Gene knockout of Acc2 has little effect on body weight, fat mass, or food intake.

    Science.gov (United States)

    Olson, David P; Pulinilkunnil, Thomas; Cline, Gary W; Shulman, Gerald I; Lowell, Bradford B

    2010-04-20

    Deletion of acetyl CoA carboxylase-2 (Acc2) reportedly causes leanness in the setting of hyperphagia. To determine the cellular basis for these effects, we generated a mouse model in which Acc2 can be selectively deleted by the action of Cre recombinase. Deletion of Acc2 from skeletal muscle, the predominant site of Acc2 expression, had no effect on body weight, food intake, or body composition. When Acc2 was inactivated in the germline, Acc2 knockout (Acc2KO) mice displayed no differences in body weight, food intake, body composition, or glucose homeostasis as compared to controls on chow or high fat diet. Total malonyl CoA content and fatty acid oxidation rates in skeletal muscle of Acc2KO mice were unchanged, suggesting metabolic compensation in response to the loss of Acc2. The limited impact of Acc2 deletion on energy balance raises the possibility that selective pharmacological inhibition of Acc2 for the treatment of obesity may be ineffective.

  4. The mu-opioid receptor gene-dose dependent reductions in G-protein activation in the pons/medulla and antinociception induced by endomorphins in mu-opioid receptor knockout mice.

    Science.gov (United States)

    Mizoguchi, H; Narita, M; Oji, D E; Suganuma, C; Nagase, H; Sora, I; Uhl, G R; Cheng, E Y; Tseng, L F

    1999-01-01

    There appear to be different relationships between mu-opioid receptor densities and the acute and neuroadaptive mu-opioid agonist-induced responses of the multiple opioid neuronal systems, including important pons/medulla circuits. The recent success in creating mu-opioid receptor knockout mice allows studies of mu-opioid agonist-induced pharmacological and physiological effects in animals that express no, one or two copies of the mu-opioid receptor gene. We now report that the binding of mu-opioid receptor ligand, [3H][D-Ala2,NHPhe4,Gly-ol]enkephalin to membrane preparations of the pons/medulla was reduced by half in heterozygous mu-opioid receptor knockout mice and eliminated in homozygous mu-opioid receptor knockout mice. The endogenous mu-opioid agonist peptides endomorphin-1 and -2 activate G-proteins in the pons/medulla from wild-type mice in a concentration-dependent fashion, as assessed using [35S]guanosine-5'-o-(3-thio)triphosphate binding. This stimulation was reduced to half of the wild-type levels in heterozygous mice and eliminated in homozygous knockout mice. The intracerebroventricular injection of either endomorphin-1 or endomorphin-2 produced marked antinociception in the hot-plate and tail-flick tests in wild-type mice. These antinociceptive actions were significantly reduced in heterozygous mu-opioid receptor knockout mice, and virtually abolished in homozygous knockout mice. The mu-opioid receptors are the principal molecular targets for endomorphin-induced G-protein activation in the pons/medulla and the antinociception caused by the intracerebroventricular administration of mu-opioid agonists. These data support the notion that there are limited physiological mu-opioid receptor reserves for inducing G-protein activation in the pons/medulla and for the nociceptive modulation induced by the central administration of endomorphin-1 and -2.

  5. Sarcocystis pantherophis, n. sp. from eastern rat snakes (Pantherophis alleghaniensis) definitive hosts and interferongamma gene knockout mice as experimental intermediate hosts

    Science.gov (United States)

    Here we report a new species, Sarcocystis pantherophisi with the Eastern rat snake (Pantherophis alleghaniensis) as natural definitive host and the interferon gamma gene knockout (KO) mouse as the experimental intermediate host. Sporocysts (n=15) from intestinal contents of the snake were 17.3 x 10....

  6. [Constructing recombinant plasmid pSH-CUP and knockout of acid trehalase gene in baker's yeast].

    Science.gov (United States)

    He, Dongqin; Xiao, Dongguang; Lv, Ye

    2008-02-01

    The ATH1 gene encoded acid trehalase in Saccharomyces cerevisiae. The gene disruption cassette combined the heterologous dominant kan(r) resistance marker with a Cre/loxP-mediated marker removal procedure. The gene disruption cassette was produced by PCR using the same long oligonucleotides comprising 50 nucleotides that annealed to sites upstream or downstream of the genomic target sequence to be deleted. After transformation of the linear disruption cassettes with a Cre/loxP-mediated marker into the cells of Saccharomyces cerevisiae BY-6, selected transformants were checked by PCR for correct the integration of the cassette and concurrent deletion of the chromosomal target sequence. The copper-resistance gene (CUP1-MT1) was cloned into pSH47, which yielded pSH-CUP. The recombinant plasmid pSH-CUP was transformed into the cells of Saccharomyces cerevisiae BY-6(delta ATH1, G418(r)), and transformants were selected for copper resistance. Upon expression of the Cre recombinase results in removal of the kan(r) gene, leaving behind a single loxP site at the chromosomal locus. Construction of the recombinant plasmid pSH-CUP avoided inserting non-yeast gene and made the loxP - kanMX - loxP gene disruption cassette more conventional for eukaryotic organism gene disruption.

  7. Effect of Cyp27A1 gene dosage on atherosclerosis development in ApoE-knockout mice.

    Science.gov (United States)

    Zurkinden, Line; Solcà, Curzio; Vögeli, Isabelle A; Vogt, Bruno; Ackermann, Daniel; Erickson, Sandra K; Frey, Felix J; Sviridov, Dmitri; Escher, Geneviève

    2014-03-01

    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 were challenged with a Western diet (WD) for 3 and 6 mo. ApoE-KO mice fed a chow diet or a WD were used as the control. The severity of atherosclerosis in DKO mice was reduced 10-fold. Compared with the control, the DKO mice had no 27-OHC, total plasma cholesterol and low-density lipoprotein and very low density lipoprotein (LDL/VLDL) concentrations were reduced 2-fold, and HDL was elevated 2-fold. Expression of hepatic CYP7A1, CYP3A, and CYP8B1 were 5- to 10-fold higher. 3-Hydroxy-3-methyl-glutaryl-CoA reductase (HMGR) activity increased 4-fold. Fecal cholesterol was increased. In contrast, het mice fed a WD developed accelerated atherosclerosis and severe skin lesions, possibly because of reduced reverse cholesterol transport due to diminished 27-OHC production. CYP27A1 activity is involved in the control of cholesterol homeostasis and development of atherosclerosis with a distinct gene dose-dependent effect.

  8. Generation and characterization of an Nxf7 knockout mouse to study NXF5 deficiency in a patient with intellectual disability.

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    Lieselot Vanmarsenille

    Full Text Available Members of the Nuclear eXport Factor (NXF family are involved in the export of mRNA from the nucleus to the cytoplasm, or hypothesized to play a role in transport of cytoplasmic mRNA. We previously reported on the loss of NXF5 in a male patient with a syndromic form of intellectual disability. To study the functional role of NXF5 we identified the mouse counterpart. Based on synteny, mouse Nxf2 is the ortholog of human NXF5. However, we provide several lines of evidence that mouse Nxf7 is the actual functional equivalent of NXF5. Both Nxf7 and NXF5 are predominantly expressed in the brain, show cytoplasmic localization, and present as granules in neuronal dendrites suggesting a role in cytoplasmic mRNA metabolism in neurons. Nxf7 was primarily detected in the pyramidal cells of the hippocampus and in layer V of the cortex. Similar to human NXF2, mouse Nxf2 is highly expressed in testis and shows a nuclear localization. Interestingly, these findings point to a different evolutionary path for both NXF genes in human and mouse. We thus generated and validated Nxf7 knockout mice, which were fertile and did not present any gross anatomical or morphological abnormalities. Expression profiling in the hippocampus and the cortex did not reveal significant changes between wild-type and Nxf7 knockout mice. However, impaired spatial memory was observed in these KO mice when evaluated in the Morris water maze test. In conclusion, our findings provide strong evidence that mouse Nxf7 is the functional counterpart of human NXF5, which might play a critical role in mRNA metabolism in the brain.

  9. Generation and characterization of an Nxf7 knockout mouse to study NXF5 deficiency in a patient with intellectual disability.

    Science.gov (United States)

    Vanmarsenille, Lieselot; Verbeeck, Jelle; Belet, Stefanie; Roebroek, Anton J; Van de Putte, Tom; Nevelsteen, Joke; Callaerts-Vegh, Zsuzsanna; D'Hooge, Rudi; Marynen, Peter; Froyen, Guy

    2013-01-01

    Members of the Nuclear eXport Factor (NXF) family are involved in the export of mRNA from the nucleus to the cytoplasm, or hypothesized to play a role in transport of cytoplasmic mRNA. We previously reported on the loss of NXF5 in a male patient with a syndromic form of intellectual disability. To study the functional role of NXF5 we identified the mouse counterpart. Based on synteny, mouse Nxf2 is the ortholog of human NXF5. However, we provide several lines of evidence that mouse Nxf7 is the actual functional equivalent of NXF5. Both Nxf7 and NXF5 are predominantly expressed in the brain, show cytoplasmic localization, and present as granules in neuronal dendrites suggesting a role in cytoplasmic mRNA metabolism in neurons. Nxf7 was primarily detected in the pyramidal cells of the hippocampus and in layer V of the cortex. Similar to human NXF2, mouse Nxf2 is highly expressed in testis and shows a nuclear localization. Interestingly, these findings point to a different evolutionary path for both NXF genes in human and mouse. We thus generated and validated Nxf7 knockout mice, which were fertile and did not present any gross anatomical or morphological abnormalities. Expression profiling in the hippocampus and the cortex did not reveal significant changes between wild-type and Nxf7 knockout mice. However, impaired spatial memory was observed in these KO mice when evaluated in the Morris water maze test. In conclusion, our findings provide strong evidence that mouse Nxf7 is the functional counterpart of human NXF5, which might play a critical role in mRNA metabolism in the brain.

  10. A one-step cloning method for the construction of somatic cell gene targeting vectors: application to production of human knockout cell lines

    OpenAIRE

    Liu Yi; Li Shangze; Zhang Huihui; Wan Zurong; Zhang Xiaodong; Du Runlei

    2012-01-01

    Abstract Background Gene targeting is a powerful method that can be used for examining the functions of genes. Traditionally, the construction of knockout (KO) vectors requires an amplification step to obtain two homologous, large fragments of genomic DNA. Restriction enzymes that cut at unique recognitions sites and numerous cloning steps are then carried out; this is often a time-consuming and frustrating process. Results We have developed a one-step cloning method for the insertion of two ...

  11. Improved reconstruction of in silico gene regulatory networks by integrating knockout and perturbation data.

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    Kevin Y Yip

    Full Text Available We performed computational reconstruction of the in silico gene regulatory networks in the DREAM3 Challenges. Our task was to learn the networks from two types of data, namely gene expression profiles in deletion strains (the 'deletion data' and time series trajectories of gene expression after some initial perturbation (the 'perturbation data'. In the course of developing the prediction method, we observed that the two types of data contained different and complementary information about the underlying network. In particular, deletion data allow for the detection of direct regulatory activities with strong responses upon the deletion of the regulator while perturbation data provide richer information for the identification of weaker and more complex types of regulation. We applied different techniques to learn the regulation from the two types of data. For deletion data, we learned a noise model to distinguish real signals from random fluctuations using an iterative method. For perturbation data, we used differential equations to model the change of expression levels of a gene along the trajectories due to the regulation of other genes. We tried different models, and combined their predictions. The final predictions were obtained by merging the results from the two types of data. A comparison with the actual regulatory networks suggests that our approach is effective for networks with a range of different sizes. The success of the approach demonstrates the importance of integrating heterogeneous data in network reconstruction.

  12. Interleukin-6 gene knockout influences energy balance regulating peptides in the hypothalamic paraventricular and supraoptic nuclei.

    Science.gov (United States)

    Benrick, A; Schéle, E; Pinnock, S B; Wernstedt-Asterholm, I; Dickson, S L; Karlsson-Lindahl, L; Jansson, J-O

    2009-07-01

    Interleukin (IL)-6 is a pro-inflammatory cytokine that also affects metabolic function because IL-6 depleted (IL-6(-/-)) mice develop late-onset obesity. IL-6 appears to act in the central nervous system, presumably in the hypothalamus, to increase energy expenditure that appears to involve stimulation of the sympathetic nervous system. In the present study, we explored possible central mechanisms for the effects exerted by IL-6 on body fat. Therefore, we measured the effects of IL-6 depletion in IL-6(-/-) mice on expression of key hypothalamic peptide genes involved in energy balance by the real time polymerase chain reaction. Additionally, co-localisation between such peptides and IL-6 receptor alpha was investigated by immunohistochemistry. IL-6 deficiency decreased the expression of several peptides found in the paraventricular nucleus (PVN), which is a nucleus that has been attributed an adipostatic function. For example, corticotrophin-releasing hormone (CRH), which is reported to stimulate the sympathetic nervous system, was decreased by 40% in older IL-6(-/-) mice. Oxytocin, which is reported to prevent obesity, was also decreased in older IL-6(-/-) animals, as was arginine vasopressin (AVP). The IL-6 receptor alpha was abundantly expressed in the PVN, but also in the supraoptic nucleus, and was shown to be co-expressed to a high extent with CRH, AVP, oxytocin and thyrotrophin-releasing hormone. These data indicate that depletion of endogenous IL-6, a body fat suppressing cytokine, is associated with the decreased expression of CRH and oxytocin (i.e. energy balance regulating peptides) as well as AVP in the PVN. Because IL-6 receptor alpha is co-expressed with CRH, oxytocin and AVP, IL-6 could stimulate the expression of these peptides directly.

  13. Generation and characterization of NV gene-knockout recombinant viral hemorrhagic septicemia virus (VHSV) genotype IVa.

    Science.gov (United States)

    Kim, Min Sun; Kim, Dong Soo; Kim, Ki Hong

    2011-11-03

    A recombinant viral hemorrhagic septicemia virus (rVHSV-deltaNV-EGFP) containing the enhanced green fluorescent protein (EGFP) gene instead of the NV gene was produced using the reverse-genetics method. For use as a positive control, another recombinant virus (rVHSV-wild) was also generated, which had an identical nucleotide sequence to the wild-type VHSV genome except for a few artificially replaced nucleotides. The rVHSVs were rescued using a system controlled by T7 RNA polymerase supplied by a retroviral vector. Generation of rVHSV-deltaNV-EGFP and rVHSV-wild was confirmed by sequencing of RT-PCR products, and rescue of infectious rVHSVs was confirmed by observation of plaque formation. Replication efficiency of rVHSV-wild was distinctly lower than that of wild-type VHSV, suggesting that the artificially replaced nucleotides, especially when immediately preceding the G or NV gene start codons, might affect the replication of the virus. Replication of rVHSV-deltaNV-EGFP was slightly lower than that of rVHSV-wild when epithelioma papulosum cyprini cells were infected with multiplicity of infection (MOI) 1.0, but much lower when cells were infected with MOI 0.00001. These results suggest that the NV gene plays an important role in VHSV replication through interactions with host-cell responses, and the lower replication ability of rVHSV-wild compared to wild-type VHSV might be caused by replaced nucleotides just before the NV gene open reading frame (ORF) rather than the G gene ORF. In olive flounder Paralichthys olivaceus, rVHSV-wild produced slower-progressing mortalities than wild-type VHSV, whereas rVHSV-deltaNV-EGFP pathogenesis was highly attenuated. These results suggest that the NV protein of VHSV may play an important role not only in viral replication but also in viral pathogenesis.

  14. Genetic knockout of the α7 nicotinic acetylcholine receptor gene alters hippocampal long-term potentiation in a background strain-dependent manner.

    Science.gov (United States)

    Freund, Ronald K; Graw, Sharon; Choo, Kevin S; Stevens, Karen E; Leonard, Sherry; Dell'Acqua, Mark L

    2016-08-01

    Reduced α7 nicotinic acetylcholine receptor (nAChR) function is linked to impaired hippocampal-dependent sensory processing and learning and memory in schizophrenia. While knockout of the Chrna7 gene encoding the α7nAChR on a C57/Bl6 background results in changes in cognitive measures, prior studies found little impact on hippocampal synaptic plasticity in these mice. However, schizophrenia is a multi-genic disorder where complex interactions between specific genetic mutations and overall genetic background may play a prominent role in determining phenotypic penetrance. Thus, we compared the consequences of knocking out the α7nAChR on synaptic plasticity in C57/Bl6 and C3H mice, which differ in their basal α7nAChR expression levels. Homozygous α7 deletion in C3H mice, which normally express higher α7nAChR levels, resulted in impaired long-term potentiation (LTP) at hippocampal CA1 synapses, while C3H α7 heterozygous mice maintained robust LTP. In contrast, homozygous α7 deletion in C57 mice, which normally express lower α7nAChR levels, did not alter LTP, as had been previously reported for this strain. Thus, the threshold of Chrna7 expression required for LTP may be different in the two strains. Measurements of auditory gating, a hippocampal-dependent behavioral paradigm used to identify schizophrenia-associated sensory processing deficits, was abnormal in C3H α7 knockout mice confirming that auditory gating also requires α7nAChR expression. Our studies highlight the importance of genetic background on the regulation of synaptic plasticity and could be relevant for understanding genetic and cognitive heterogeneity in human studies of α7nAChR dysfunction in mental disorders.

  15. Gene expression and mRNA editing of serotonin receptor 2C in brains of HPRT gene knock-out mice, an animal model of Lesch-Nyhan disease

    Science.gov (United States)

    Bertelli, Matteo; Alushi, Brunilda; Veicsteinas, Arsenio; Jinnah, H.A.; Micheli, Vanna

    2016-01-01

    Lesch-Nyhan disease (LND), a genetic disorder associated with motor and psychiatric disturbance and self-injurious behaviour (SIB) is caused by a complete deficiency of hypoxanthine-guanine phosphoribosyltransferase (HPRT). The connection between enzyme deficiency and neurological involvement is still unclear. Evidence exists for a role of basal ganglia dysfunction with decreased dopamine and excess serotonin striatal content. In this study, we investigate the role of serotonin receptor 2C (HTR2C) in the brains of HPRT gene knock-out mice, a model of LND. HTR2C expression is analyzed by real-time polymerase chain reaction (PCR) using SYBR-green detection methods. The percentage of edited HTR2C mRNA was determined by direct sequencing of amplification products of the region containing the editing sites. We found a 55% increase in the expression of HTR2C gene but no significant difference in mRNA editing levels between knock-out and control mice. The above alteration found in HPRT-deficient mice is similar to those found in other animal models used to study aggressive and self-injurious behaviour. PMID:19473847

  16. [Effects of knockout ECM25/YJL201W gene in brewing yeast on beer flavor stability].

    Science.gov (United States)

    Zhang, Yixin; Li, Qi; Shen, Wei; Xie, Yan; Gu, Guoxian

    2008-08-01

    The ECM25 deletion mutant of industrial brewing yeast, G03/a, was constructed by replacing the ECM25 gene with the kanMX gene. The transformant was verified to be genetically stable. The PCR analysis showed that ECM25 gene in the G-03/a was deleted. Under aerobic conditions of ll degrees C and 28 degrees C, compared with the host strain G-03, the excretive glutathione concentration of G-03/a increased by 21.4% and 14.7%, respectively. Strains G-03 and G-03/a were inoculated in flasks and cultivated continuously for 4 generations. Compared with the host strain G-03, the glutathione concentration in the main fermentation broth and final beer of strain G-03/a increased by 32.1% and 13.8%, the stability index (SI) increased by 7.7% and 5.3%, respectively, and the flavor resistance staling value (RSV value) in final beer increased by 45.0%. During EBC fermentation, the glutathione concentration in the main fermentation broth of strain G-03/a increased by 34.0%, compared with the host strain G-03. Furthermore, no significant difference in routine fermentation parameters was found. The strain G-03/a is proved to be an excellent anti-staling brewing yeast to improve beer flavor stability.

  17. Knockout of Lysosomal Enzyme-Targeting Gene Causes Abnormalities in Mouse Pup Isolation Calls

    Science.gov (United States)

    Barnes, Terra D.; Holy, Timothy E.

    2017-01-01

    Humans lacking a working copy of the GNPTAB gene suffer from the metabolic disease Mucolipidosis type II (MLII). MLII symptoms include mental retardation, skeletal deformities and cartilage defects as well as a speech delay with most subjects unable to utter single words (Otomo et al., 2009; Cathey et al., 2010; Leroy et al., 2012). Here we asked whether mice lacking a copy of Gnptab gene exhibited vocal abnormities. We recorded ultrasonic vocalizations from 5 to 8 day old mice separated from their mother and littermates. Although Gnptab−/− pups emitted a similar number of calls, several features of the calls were different from their wild type littermates. Gnptab−/− mice showed a decrease in the length of calls, an increase in the intra-bout pause duration, significantly fewer pitch jumps with smaller mean size, and an increase in the number of isolated calls. In addition, Gnptab−/− mice vocalizations had less power, particularly in the higher frequencies. Gnptab+/− mouse vocalizations did not appear to be affected. We then attempted to classify these recordings using these features to determine the genotype of the animal. We were able to correctly identify 87% of the recordings as either Gnptab−/− or Gnptab+/+ pup, significantly better than chance, demonstrating that genotype is a strong predictor of vocalization phenotype. These data show that deletion of genes in the lysosomal enzyme targeting pathway affect mouse pup isolation calls.

  18. Engineering of Corynebacterium glutamicum to Enhance L-ornithine Production by Gene Knockout and Comparative Proteomic Analysis

    Institute of Scientific and Technical Information of China (English)

    卢冬梅; 刘建忠; 毛宗万

    2012-01-01

    Engineered Corynebacterium glutamicum was constructed for L-ornithine production by disrupting genes of argF and proB to prevent the flux away from L-ornithine.Effect of the inactivation of 2-oxoglutarate de-hydrogenase complex(ODHC) on L-ornithine production was also investigated.It was found that the inactivation of ODHC by knockout of the kgd gene enhanced L-ornithine production.The engineered C.glutamicum ATCC13032(ΔargFΔproBΔkgd) produced L-ornithine up to 4.78 g·L-1 from 0.24 g·L-1 of the wild-type strain.In order to understand the mechanism of L-ornithine production in C.glutamicum ATCC13032(ΔargFΔproBΔkgd) and find out new strategies for further enhancing L-ornithine production,the comparative proteome between the wild-type and the engineered strain was analyzed.L-Ornithine overproduction in the engineered strain was related to the up-regulation of the expression levels of enzymes involved in L-ornithine biosynthesis pathway and down-regulation of the expression levels of proteins involved in pentose phosphate pathway.The overexpression of genes in the upstream pathway of glutamate to increase the availability of endogenous glutamate may further in-crease ornithine production in the engineered C.glutamicum and the ornithine synthesis enzymes(ArgCJBD) may not be the limiting enzymes in the engineered C.glutamicum.

  19. Synthetic liver X receptor agonist T0901317 inhibits semicarbazide-sensitive amine oxidase gene expression and activity in apolipoprotein E knockout mice

    Institute of Scientific and Technical Information of China (English)

    Xiaoyan Dai; Xiang Ou; Xinrui Hao; Dongli Cao; Yaling Tang; Yanwei Hu; Xiaoxu Li; Chaoke Tang

    2008-01-01

    Semicarbazide-sensitive amine oxidase(SSAO)catalyzes oxidative deamination of primary aromatic and aliphatic amines.Increased SSAO activity has been found in atherosclerosis and diabetes mellitus.We hypothesize that the anti-atherogenic effect of liver X receptors(LXRs)might be related to the inhibition of SSAD gene expression and its activity.In this study,we investigated the effect of LXR agonist T0901317 on SSAO gene expression and its activity in apolipoprotein E knockout(apoE-/-)mice.Male apoE-/-mice(8 weeks old) were randomly divided into four groups:basal control group;vehicle group;prevention group;and treatment group.SSAO gene expression was analyzed by real-time quantitative polymerase chain reaction and its activity was determined.The activity of superoxide dismutase and content of malondialdehy de in the aorta and liver were also determined.In T0901317-treated mice,SSAO gene expression was significantly decreased in the aorta,liver,small intestine,and brain.SSAO activities in serum and in these tissues were also inhibited.The amount of superoxide dismutase in the aorta and liver of the prevention group and treatment group was significantly higher compared with the vehicle group(P<0.05).Malondialdehyde in the tissues of these two groups was significantly lower compared with the vehicle group(P<0.05).Our results showed that T0901317 inhibits SSAO gene expression and its activity in atherogenic apoE-/-mice.The atheroprotective effect of LXR agonist T0901317 is related to the inhibition of SSAO gene expression and its activity.

  20. Metabonomic study of the biochemical profiles of heterozygous myostatin knockout swine

    Directory of Open Access Journals (Sweden)

    Jianxiang XU,Dengke PAN,Jie ZHAO,Jianwu WANG,Xiaohong HE,Yuehui MA,Ning LI

    2015-03-01

    Full Text Available Myostatin is a transforming growth factor-β family member that normally acts to limit skeletal muscle growth. Myostatin gene (MSTN knockout (KO mice show possible effects for the prevention or treatment of metabolic disorders such as obesity and type 2 diabetes. We applied chromatography and mass spectrometry based metabonomics to assess system-wide metabolic response of heterozygous MSTN KO (MSTN+/- swine. Most of the metabolic data for MSTN+/- swine were similar to the data for wild type (WT control swine. There were, however, metabolic changes related to fatty acid metabolism, glucose utilization, lipid metabolism, as well as BCAA catabolism caused by monoallelic MSTN depletion.The statistical analyses suggested that: (1 most metabolic changes were not significant in MSTN+/- swine compared to WT swine; (2 only a few metabolic properties were significantly different between KO and WT swine, especially for lipid metabolism. Significantly, these minor changes were most evident in female KO swine and suggested differences in gender sensitivity to myostatin.

  1. A Genome-Wide Knockout Screen to Identify Genes Involved in Acquired Carboplatin Resistance

    Science.gov (United States)

    2016-07-01

    cell lines are more difficult to infect in general. We first tested the infectability of 5 ovarian cancer cell lines, COV318, CAVO3, UCI-107, OVCAR-8...assistance of the Gene Transfer and Targeting core laboratory at the Salk Institute tested the lentiviral preparation on HEK-293T cells and used primers...resistance in ovarian cancers. J Bioinform Comput Biol 2007;5(2a):383-405. 16. Fridley BL, Abo R, Tan XL, Jenkins GD, Batzler A, Moyer AM, et al

  2. Triple immunoglobulin gene knockout transchromosomic cattle: bovine lambda cluster deletion and its effect on fully human polyclonal antibody production.

    Directory of Open Access Journals (Sweden)

    Hiroaki Matsushita

    Full Text Available Towards the goal of producing fully human polyclonal antibodies (hpAbs or hIgGs in transchromosomic (Tc cattle, we previously reported that Tc cattle carrying a human artificial chromosome (HAC comprising the entire unrearranged human immunoglobulin (Ig heavy-chain (hIGH, kappa-chain (hIGK, and lambda-chain (hIGL germline loci produced physiological levels of hIgGs when both of the bovine immunoglobulin mu heavy-chains, bIGHM and bIGHML1, were homozygously inactivated (bIGHM-/-, bIGHML1-/-; double knockouts or DKO. However, because endogenous bovine immunoglobulin light chain loci are still intact, the light chains are produced both from the hIGK and hIGL genomic loci on the HAC and from the endogenous bovine kappa-chain (bIGK and lambda-chain (bIGL genomic loci, resulting in the production of fully hIgGs (both Ig heavy-chains and light-chains are of human origin: hIgG/hIgκ or hIgG/hIgλ and chimeric hIgGs (Ig heavy-chains are of human origin while the Ig light-chains are of bovine origin: hIgG/bIgκ or hIgG/bIgλ. To improve fully hIgG production in Tc cattle, we here report the deletion of the entire bIGL joining (J and constant (C gene cluster (bIGLJ1-IGLC1 to bIGLJ5-IGLC5 by employing Cre/loxP mediated site-specific chromosome recombination and the production of triple knockout (bIGHM-/-, bIGHML1-/- and bIGL-/-; TKO Tc cattle. We further demonstrate that bIGL cluster deletion greatly improves fully hIgGs production in the sera of TKO Tc cattle, with 51.3% fully hIgGs (hIgG/hIgκ plus hIgG/hIgλ.

  3. Gene knockout and overexpression analysis revealed the role of N-acetylmuramidase in autolysis of Lactobacillus delbrueckii subsp. bulgaricus ljj-6.

    Science.gov (United States)

    Pang, Xiao-Yang; Cui, Wen-Ming; Liu, Lu; Zhang, Shu-Wen; Lv, Jia-Ping

    2014-01-01

    Autolysis of lactic acid bacteria (LAB) plays a vital role in dairy processing. During cheese making, autolysis of LAB affects cheese flavor development through release of intracellular enzymes and restricts the proliferation of cells in yogurt fermentation and probiotics production. In order to explore the mechanism of autolysis, the gene for the autolytic enzymes of L. bulgaricus, N-acetylmuramidase (mur), was cloned and sequenced (GenBank accession number: KF157911). Mur gene overexpression and gene knockout vectors were constructed based on pMG76e and pUC19 vectors. Recombinant plasmids were transformed into L. bulgaricus ljj-6 by electroporation, then three engineered strains with pMG76e-mur vector and fifteen engineered strains with pUC19-mur::EryBII were screened. The autolysis of the mur knockout strain was significantly lower and autolysis of the mur overexpressed strain was significantly higher compared with that of the wild type strain ljj-6. This result suggested that the mur gene played an important role in autolysis of L. bulgaricus. On the other hand, autolytic activity in a low degree was still observed in the mur knockout strain, which implied that other enzymes but autolysin encoded by mur were also involved in autolysis of L. bulgaricus.

  4. Gene knockout and overexpression analysis revealed the role of N-acetylmuramidase in autolysis of Lactobacillus delbrueckii subsp. bulgaricus ljj-6.

    Directory of Open Access Journals (Sweden)

    Xiao-Yang Pang

    Full Text Available Autolysis of lactic acid bacteria (LAB plays a vital role in dairy processing. During cheese making, autolysis of LAB affects cheese flavor development through release of intracellular enzymes and restricts the proliferation of cells in yogurt fermentation and probiotics production. In order to explore the mechanism of autolysis, the gene for the autolytic enzymes of L. bulgaricus, N-acetylmuramidase (mur, was cloned and sequenced (GenBank accession number: KF157911. Mur gene overexpression and gene knockout vectors were constructed based on pMG76e and pUC19 vectors. Recombinant plasmids were transformed into L. bulgaricus ljj-6 by electroporation, then three engineered strains with pMG76e-mur vector and fifteen engineered strains with pUC19-mur::EryBII were screened. The autolysis of the mur knockout strain was significantly lower and autolysis of the mur overexpressed strain was significantly higher compared with that of the wild type strain ljj-6. This result suggested that the mur gene played an important role in autolysis of L. bulgaricus. On the other hand, autolytic activity in a low degree was still observed in the mur knockout strain, which implied that other enzymes but autolysin encoded by mur were also involved in autolysis of L. bulgaricus.

  5. 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 (SERT-/

  6. 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 (SERT(-

  7. PLEKHQ1基因敲除小鼠基因型鉴定方法%The method of the identification of the PLEKHQ1 gene knockout mice

    Institute of Scientific and Technical Information of China (English)

    张鹏飞; 张硌; 陆琤; 周晨辰

    2015-01-01

    目的:探讨鉴定PLEKHQ1基因敲除(KO)小鼠基因型的方法。方法:对PLEKHQ1基因敲除杂合子小鼠进行单独饲养及配种繁殖,繁殖后其子代出现野生型、杂合子型及纯合子型3种基因型,提取每只小鼠的基因组DNA,采用聚合酶链反应(PCR)和变性方法进行基因类型鉴定。结果:采用PCR和变性法成功鉴定出PLEKHQ1基因敲除小鼠的基因型。结论:这种无需T7酶切的小鼠基因型鉴定方法可用于PLEKHQ1基因敲除小鼠的基因型鉴定。%Objective:To identify PLEKHQ1 gene knock-out mice.Methods: The PLEKHQ1 gene knock-out heterozygote mice were bred alone and copulated. The offsprings were to have three genotypes: wild genotype, heterozygote genotype and homozygote genotype. Genomic DNA was obtained from each pups and were subjected to PCR and Denature to identify the genotype. Results: The identification of PLEKHQ1 gene knockout mice is successful.Conclusion: The identification method of PLEKHQ1-KO mice without T7 can correct identify PLEKHQ1 gene knockout mice.

  8. Studies on functional roles of the histaminergic neuron system by using pharmacological agents, knockout mice and positron emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, Takehiko; Yanai, Kazuhiko [Tohoku Univ., Sendai (Japan). Graduate School of Medicine

    2001-12-01

    Since one of us, Takehiko Watanabe (TW), elucidated the location and distribution of the histaminergic neuron system in the brain with antibody raised against L-histidine decarboxylase (a histamine-forming enzyme, HDC) as a marker in 1984 and came to Tohoku University School of Medicine in Sendai, we have been collaborating on the functions of this neuron system by using pharmacological agents, knockout mice of the histamine-related genes, and, in some cases, positron emission tomography (PET). Many of our graduate students and colleagues have been actively involved in histamine research since 1985. Our extensive studies have clarified some of the functions of histamine neurons using methods from molecular techniques to non-invasive human PET imaging. Histamine neurons are involved in many brain functions, such as spontaneous locomotion, arousal in wake-sleep cycle, appetite control, seizures, learning and memory, aggressive behavior and emotion. Particularly, the histaminergic neuron system is one of the most important neuron systems to maintain and stimulate wakefulness. Histamine also functions as a biprotection system against various noxious and unfavorable stimuli (for examples, convulsion, nociception, drug sensitization, ischemic lesions, and stress). Although activators of histamine neurons have not been clinically available until now, we would like to point out that the activation of the histaminergic neuron system is important to maintain mental health. Here, we summarize the newly-discovered functions of histamine neurons mainly on the basis of results from our research groups. (author)

  9. Genetic knockout and pharmacological blockade studies of the 5-HT7 receptor suggest therapeutic potential in depression.

    Science.gov (United States)

    Guscott, M; Bristow, L J; Hadingham, K; Rosahl, T W; Beer, M S; Stanton, J A; Bromidge, F; Owens, A P; Huscroft, I; Myers, J; Rupniak, N M; Patel, S; Whiting, P J; Hutson, P H; Fone, K C; Biello, S M; Kulagowski, J J; McAllister, G

    2005-03-01

    The affinity of several antidepressant and antipsychotic drugs for the 5-HT7 receptor and its CNS distribution suggest potential in the treatment of psychiatric diseases. However, there is little direct evidence of receptor function in vivo to support this. We therefore evaluated 5-HT7 receptors as a potential drug target by generating and assessing a 5-HT7 receptor knockout mouse. No difference in assays sensitive to potential psychotic or anxiety states was observed between the 5-HT7 receptor knockout mice and wild type controls. However, in the Porsolt swim test, 5-HT7 receptor knockout mice showed a significant decrease in immobility compared to controls, a phenotype similar to antidepressant treated mice. Intriguingly, treatment of wild types with SB-258719, a selective 5-HT7 receptor antagonist, did not produce a significant decrease in immobility unless animals were tested in the dark (or active) cycle, rather than the light, adding to the body of evidence suggesting a circadian influence on receptor function. Extracellular recordings from hypothalamic slices showed that circadian rhythm phase shifts to 8-OH-DPAT are attenuated in the 5-HT7 receptor KO mice also indicating a role for the receptor in the regulation of circadian rhythms. These pharmacological and genetic knockout studies provide the first direct evidence that 5-HT7 receptor antagonists should be investigated for efficacy in the treatment of depression.

  10. Knockout of the DNA ligase IV homolog gene in the sphingoid base producing yeast Pichia ciferrii significantly increases gene targeting efficiency.

    Science.gov (United States)

    Schorsch, Christoph; Köhler, Tim; Boles, Eckhard

    2009-08-01

    The yeast Pichia ciferrii produces large quantities of the sphingoid base tetraacetyl phytosphingosine (TAPS) and is an interesting platform organism for the biotechnological production of sphingolipids and ceramides. Ceramides have attracted great attention as a specialty ingredient for moisture retention and protection of the skin in the cosmetics industry. First attempts have been started to metabolically engineer P. ciferrii for improved production of TAPS and other sphingoid bases. However, rational metabolic engineering of P. ciferrii is difficult due to a low gene targeting efficiency. In eukaryotes, two major pathways coexist, which are responsible for genomic DNA integration, homologous recombination (HR) and non-homologous end joining (NHEJ). Integration via HR is targeted, while NHEJ involves ectopic (non-targeted) integration depending on a ligation step mediated by DNA ligase IV (Lig4). Here, we demonstrate a dramatical increase in gene targeting efficiency in a P. ciferrii lig4 knockout strain, deficient in NHEJ. Furthermore, a quick and easy to use freeze-thaw method was developed to transform P. ciferrii with high efficiency. Owing to the ability of targeting genomic DNA integration our results pave the way for further genetic and metabolic engineering approaches with P. ciferrii by means of knocking out or overexpressing predestinated genes.

  11. Homologous Cloning of Clostridium Hydrogenase Gene and Construction of Gene Knockout Vector%梭菌氢酶基因部分片段的同源克隆及敲除载体的构建

    Institute of Scientific and Technical Information of China (English)

    闫倩; 闫苗章; 王保莉; 曲东

    2012-01-01

    Dissimilatory iron-reducing bacteria grown in soil play an important role in bioremediation of organics and heavy metal pollution. The aim of this study is to explore the internal relationship between the iron-reducing ability and hydrogen-evolution of Clostridium, which is a typical iron-reducing bacteria. In this paper, a Clostridium strain isolated from paddy soil as the research object. Using homologous clone, a fragment (761 bp) of hydrogenase gene was obtained. Bioinformatics analysis showed that this gene fragment contained the active centers of hydrogenase, and was its major functional domain. Moreover, knockout vector (pMD-19-HTH) included tetracycline resistance gene was constructed by overlap PCR technique with the purpose of knockout hydrogenase function and lay the foundation for uncovering relationship between the iron-reducing ability and hydrogen-evolution.%为从分子水平探索典型铁还原菌一梭菌的铁还原能力与其氢酶产氢之间的关系,以从水稻土中分离得到一株具有高铁还原能力和高产氢能力的梭菌为材料,通过同源克隆获得长度为761 bp氢酶基因的部分序列.生物信息分析发现,该基因片段覆盖氢酶的活性中心,是氢酶的主要功能结构域.采用Overlap PCR的方法构建含有四环素抗性基因的氢酶基因敲除载体(pMD-19-HTH),以期进一步构建氢酶基因缺失的梭菌突变体,为分析氢酶产氢与铁还原的关系奠定基础.

  12. Comparative N-linked glycan analysis of wild-type and α1,3-galactosyltransferase gene knock-out pig fibroblasts using mass spectrometry approaches.

    Science.gov (United States)

    Park, Hae-Min; Kim, Yoon-Woo; Kim, Kyoung-Jin; Kim, Young June; Yang, Yung-Hun; Jin, Jang Mi; Kim, Young Hwan; Kim, Byung-Gee; Shim, Hosup; Kim, Yun-Gon

    2015-01-31

    Carbohydrate antigens expressed on pig cells are considered to be major barriers in pig-to-human xenotransplantation. Even after α1,3-galactosyltransferase gene knock-out (GalT-KO) pigs are generated, potential non-Gal antigens are still existed. However, to the best of our knowledge there is no extensive study analyzing N-glycans expressed on the GalT-KO pig tissues or cells. Here, we identified and quantified totally 47 N-glycans from wild-type (WT) and GalT-KO pig fibroblasts using mass spectrometry. First, our results confirmed the absence of galactose-alpha-1,3-galactose (α-Gal) residue in the GalT-KO pig cells. Interestingly, we showed that the level of overall fucosylated N-glycans from GalT-KO pig fibroblasts is much higher than from WT pig fibroblasts. Moreover, the relative quantity of the N-glycolylneuraminic acid (NeuGc) antigen is slightly higher in the GalT-KO pigs. Thus, this study will contribute to a better understanding of cellular glycan alterations on GalT-KO pigs for successful xenotransplantation.

  13. IL-4-dependent effector phase in autoimmune exocrinopathy as defined by the NOD.IL-4-gene knockout mouse model of Sjögren's syndrome.

    Science.gov (United States)

    Brayer, J B; Cha, S; Nagashima, H; Yasunari, U; Lindberg, A; Diggs, S; Martinez, J; Goa, J; Humphreys-Beher, M G; Peck, A B

    2001-01-01

    NOD mice manifest many features of autoimmune exocrinopathy (Sjögren's syndrome), a disease generally characterized by a chronic, progressive immunological attack against the exocrine tissues of the salivary and lacrimal glands. Previous studies using the NOD congenic partner strain, NOD.Igmu(null), defined an important role for B lymphocytes in the development of xerostomia, implicating autoantibodies reactive with the acetylcholine muscarinic receptor (M3R) as the possible effector mechanism. In the present study, we have examined the impact of the cytokine, interleukin (IL)-4, on autoimmune exocrinopathy by using the IL-4 gene knockout (KO) NOD mouse strain, NOD.IL-4-/-. Despite manifesting the physiological aberrations and marked leukocytic infiltration of the salivary glands characteristic of autoimmune xerostomia in NOD mice, the NOD.IL-4-/- mice do not develop xerostomia. However, NOD.IL-4-/- mice that received adoptively transferred T lymphocytes derived from NOD.Igmu-/- mice progress to xerostomia, thereby reversing the defect. While progression or lack of progression to xerostomia correlated with the ability of the NOD.IL-4-/- mice to express detectable anti-M3R autoantibodies, the precise mechanism of how IL-4 influences the development of autoimmune xerostomia remains speculative.

  14. Multiple phenotypic changes in mice after knockout of the B3gnt5 gene, encoding Lc3 synthase--a key enzyme in lacto-neolacto ganglioside synthesis

    Directory of Open Access Journals (Sweden)

    McLendon Roger E

    2010-11-01

    Full Text Available Abstract Background Ganglioside biosynthesis occurs through a multi-enzymatic pathway which at the lactosylceramide step is branched into several biosynthetic series. Lc3 synthase utilizes a variety of galactose-terminated glycolipids as acceptors by establishing a glycosidic bond in the beta-1,3-linkage to GlcNaAc to extend the lacto- and neolacto-series gangliosides. In order to examine the lacto-series ganglioside functions in mice, we used gene knockout technology to generate Lc3 synthase gene B3gnt5-deficient mice by two different strategies and compared the phenotypes of the two null mouse groups with each other and with their wild-type counterparts. Results B3gnt5 gene knockout mutant mice appeared normal in the embryonic stage and, if they survived delivery, remained normal during early life. However, about 9% developed early-stage growth retardation, 11% died postnatally in less than 2 months, and adults tended to die in 5-15 months, demonstrating splenomegaly and notably enlarged lymph nodes. Without lacto-neolacto series gangliosides, both homozygous and heterozygous mice gradually displayed fur loss or obesity, and breeding mice demonstrated reproductive defects. Furthermore, B3gnt5 gene knockout disrupted the functional integrity of B cells, as manifested by a decrease in B-cell numbers in the spleen, germinal center disappearance, and less efficiency to proliferate in hybridoma fusion. Conclusions These novel results demonstrate unequivocally that lacto-neolacto series gangliosides are essential to multiple physiological functions, especially the control of reproductive output, and spleen B-cell abnormality. We also report the generation of anti-IgG response against the lacto-series gangliosides 3'-isoLM1 and 3',6'-isoLD1.

  15. The FKBP5 Gene Affects Alcohol Drinking in Knockout Mice and Is Implicated in Alcohol Drinking in Humans

    Directory of Open Access Journals (Sweden)

    Bin Qiu

    2016-08-01

    Full Text Available FKBP5 encodes FK506-binding protein 5, a glucocorticoid receptor (GR-binding protein implicated in various psychiatric disorders and alcohol withdrawal severity. The purpose of this study is to characterize alcohol preference and related phenotypes in Fkbp5 knockout (KO mice and to examine the role of FKBP5 in human alcohol consumption. The following experiments were performed to characterize Fkpb5 KO mice. (1 Fkbp5 KO and wild-type (WT EtOH consumption was tested using a two-bottle choice paradigm; (2 The EtOH elimination rate was measured after intraperitoneal (IP injection of 2.0 g/kg EtOH; (3 Blood alcohol concentration (BAC was measured after 3 h limited access of alcohol; (4 Brain region expression of Fkbp5 was identified using LacZ staining; (5 Baseline corticosterone (CORT was assessed. Additionally, two SNPs, rs1360780 (C/T and rs3800373 (T/G, were selected to study the association of FKBP5 with alcohol consumption in humans. Participants were college students (n = 1162 from 21–26 years of age with Chinese, Korean or Caucasian ethnicity. The results, compared to WT mice, for KO mice exhibited an increase in alcohol consumption that was not due to differences in taste sensitivity or alcohol metabolism. Higher BAC was found in KO mice after 3 h of EtOH access. Fkbp5 was highly expressed in brain regions involved in the regulation of the stress response, such as the hippocampus, amygdala, dorsal raphe and locus coeruleus. Both genotypes exhibited similar basal levels of plasma corticosterone (CORT. Finally, single nucleotide polymorphisms (SNPs in FKBP5 were found to be associated with alcohol drinking in humans. These results suggest that the association between FKBP5 and alcohol consumption is conserved in both mice and humans.

  16. The FKBP5 Gene Affects Alcohol Drinking in Knockout Mice and Is Implicated in Alcohol Drinking in Humans.

    Science.gov (United States)

    Qiu, Bin; Luczak, Susan E; Wall, Tamara L; Kirchhoff, Aaron M; Xu, Yuxue; Eng, Mimy Y; Stewart, Robert B; Shou, Weinian; Boehm, Stephen L; Chester, Julia A; Yong, Weidong; Liang, Tiebing

    2016-08-05

    FKBP5 encodes FK506-binding protein 5, a glucocorticoid receptor (GR)-binding protein implicated in various psychiatric disorders and alcohol withdrawal severity. The purpose of this study is to characterize alcohol preference and related phenotypes in Fkbp5 knockout (KO) mice and to examine the role of FKBP5 in human alcohol consumption. The following experiments were performed to characterize Fkpb5 KO mice. (1) Fkbp5 KO and wild-type (WT) EtOH consumption was tested using a two-bottle choice paradigm; (2) The EtOH elimination rate was measured after intraperitoneal (IP) injection of 2.0 g/kg EtOH; (3) Blood alcohol concentration (BAC) was measured after 3 h limited access of alcohol; (4) Brain region expression of Fkbp5 was identified using LacZ staining; (5) Baseline corticosterone (CORT) was assessed. Additionally, two SNPs, rs1360780 (C/T) and rs3800373 (T/G), were selected to study the association of FKBP5 with alcohol consumption in humans. Participants were college students (n = 1162) from 21-26 years of age with Chinese, Korean or Caucasian ethnicity. The results, compared to WT mice, for KO mice exhibited an increase in alcohol consumption that was not due to differences in taste sensitivity or alcohol metabolism. Higher BAC was found in KO mice after 3 h of EtOH access. Fkbp5 was highly expressed in brain regions involved in the regulation of the stress response, such as the hippocampus, amygdala, dorsal raphe and locus coeruleus. Both genotypes exhibited similar basal levels of plasma corticosterone (CORT). Finally, single nucleotide polymorphisms (SNPs) in FKBP5 were found to be associated with alcohol drinking in humans. These results suggest that the association between FKBP5 and alcohol consumption is conserved in both mice and humans.

  17. The FKBP5 Gene Affects Alcohol Drinking in Knockout Mice and Is Implicated in Alcohol Drinking in Humans

    Science.gov (United States)

    Qiu, Bin; Luczak, Susan E.; Wall, Tamara L.; Kirchhoff, Aaron M.; Xu, Yuxue; Eng, Mimy Y.; Stewart, Robert B.; Shou, Weinian; Boehm, Stephen L.; Chester, Julia A.; Yong, Weidong; Liang, Tiebing

    2016-01-01

    FKBP5 encodes FK506-binding protein 5, a glucocorticoid receptor (GR)-binding protein implicated in various psychiatric disorders and alcohol withdrawal severity. The purpose of this study is to characterize alcohol preference and related phenotypes in Fkbp5 knockout (KO) mice and to examine the role of FKBP5 in human alcohol consumption. The following experiments were performed to characterize Fkpb5 KO mice. (1) Fkbp5 KO and wild-type (WT) EtOH consumption was tested using a two-bottle choice paradigm; (2) The EtOH elimination rate was measured after intraperitoneal (IP) injection of 2.0 g/kg EtOH; (3) Blood alcohol concentration (BAC) was measured after 3 h limited access of alcohol; (4) Brain region expression of Fkbp5 was identified using LacZ staining; (5) Baseline corticosterone (CORT) was assessed. Additionally, two SNPs, rs1360780 (C/T) and rs3800373 (T/G), were selected to study the association of FKBP5 with alcohol consumption in humans. Participants were college students (n = 1162) from 21–26 years of age with Chinese, Korean or Caucasian ethnicity. The results, compared to WT mice, for KO mice exhibited an increase in alcohol consumption that was not due to differences in taste sensitivity or alcohol metabolism. Higher BAC was found in KO mice after 3 h of EtOH access. Fkbp5 was highly expressed in brain regions involved in the regulation of the stress response, such as the hippocampus, amygdala, dorsal raphe and locus coeruleus. Both genotypes exhibited similar basal levels of plasma corticosterone (CORT). Finally, single nucleotide polymorphisms (SNPs) in FKBP5 were found to be associated with alcohol drinking in humans. These results suggest that the association between FKBP5 and alcohol consumption is conserved in both mice and humans. PMID:27527158

  18. Novel roles for metallothionein-I + II (MT-I + II) in defense responses, neurogenesis, and tissue restoration after traumatic brain injury: insights from global gene expression profiling in wild-type and MT-I + II knockout mice

    DEFF Research Database (Denmark)

    Penkowa, Milena; Cáceres, Mario; Borup, Rehannah

    2006-01-01

    . A genomic approach, such as the use of microarrays, provides much insight in this regard, especially if combined with the use of gene-targeted animals. We report here the results of one of these studies comparing wild-type and metallothionein-I + II knockout mice subjected to a cryolesion...... times consistent with the processes involved in the initial tissue injury and later regeneration of the parenchyma, as well as a prominent effect of MT-I + II deficiency. The results thoroughly confirmed the importance of the antioxidant proteins MT-I + II in the response of the brain to injury...

  19. A study of the single neutron knockout reaction from silicon-26 and sulfur-30

    Science.gov (United States)

    Reynolds, Robert R., Jr.

    transitions between energy levels in both 25Si and 29S. Two new gamma-rays were observed for 25Si at 821(15) keV and 1088(22) keV. The 821(15) keV gamma-ray is a direct decay from the first 1/2+ state to the 5/2+ ground state, while the 1088(22) keV gamma-ray is actually a result of a 3/2+ state at 1909(27) keV feeding into the 1/2+ state at 821(15) keV. The measured cross sections for the 26Sigamma→ 25Si reaction were sigma(inclusive) = 26.1(35) mb, sigma(1909keV ) = 1.06(21) mb, and sigma(821 keV ) = 4.06(61) mb. There were three new gamma-ray transitions seen for 29S with energies of 1160(16) keV, 1222(20) keV, and 1727(37) keV, which correspond to the first experimental observation of excited states in 29S. The 1222(20) keV decay is the direct decay from the 1/2+ first excited state to the 5/2+ ground state, while the 1727(37) keV gamma-ray is the decay of the 7/2+ state to the ground state, however the 1727(37) keV state is only populated by direct feeding from the 5/2+ state at 2887(40) keV by the observed 1160(16) keV gamma-ray. The measured cross sections for the 30S→ 29S reaction were sigma(inclusive) = 27.5(26) mb, sigma(1222 keV) = 3.09(33) mb, and sigma(2887keV) = 1.86(15) mb. The reduction factor to the shell model spectroscopic strength for the inclusive cross section for the 26Si→25Si reaction is 0.55(7) and the reduction factor for the inclusive cross section for the 30S→29S reaction is 0.46(4). With valence binding separation energy differences of DeltaS = 13.5 MeV for 26Si and DeltaS = 14.6 MeV for 30S, these reduction factors are in good agreement with the systematic behavior of reduction factors from other single nucleon knockout reaction studies. The calculated electromagnetic multipole transition strengths in both 25Si and 29S, when taken into consideration with the observed decay branching ratios, allows some speculation that these nuclei are well-deformed and that the known region of deformation in the sd-shell extends out to both. Based on the

  20. Bile Salt Homeostasis in Normal and Bsep Gene Knockout Rats with Single and Repeated Doses of Troglitazone.

    Science.gov (United States)

    Cheng, Yaofeng; Chen, Shenjue; Freeden, Chris; Chen, Weiqi; Zhang, Yueping; Abraham, Pamela; Nelson, David M; Humphreys, W Griffith; Gan, Jinping; Lai, Yurong

    2017-09-01

    The interference of bile acid secretion through bile salt export pump (BSEP) inhibition is one of the mechanisms for troglitazone (TGZ)-induced hepatotoxicity. Here, we investigated the impact of single or repeated oral doses of TGZ (200 mg/kg/day, 7 days) on bile acid homoeostasis in wild-type (WT) and Bsep knockout (KO) rats. Following oral doses, plasma exposures of TGZ were not different between WT and KO rats, and were similar on day 1 and day 7. However, plasma exposures of the major metabolite, troglitazone sulfate (TS), in KO rats were 7.6- and 9.3-fold lower than in WT on day 1 and day 7, respectively, due to increased TS biliary excretion. With Bsep KO, the mRNA levels of multidrug resistance-associated protein 2 (Mrp2), Mrp3, Mrp4, Mdr1, breast cancer resistance protein (Bcrp), sodium taurocholate cotransporting polypeptide, small heterodimer partner, and Sult2A1 were significantly altered in KO rats. Following seven daily TGZ treatments, Cyp7A1 was significantly increased in both WT and KO rats. In the vehicle groups, plasma exposures of individual bile acids demonstrated variable changes in KO rats as compared with WT. WT rats dosed with TGZ showed an increase of many bile acid species in plasma on day 1, suggesting the inhibition of Bsep. Conversely, these changes returned to base levels on day 7. In KO rats, alterations of most bile acids were observed after seven doses of TGZ. Collectively, bile acid homeostasis in rats was regulated through bile acid synthesis and transport in response to Bsep deficiency and TGZ inhibition. Additionally, our study is the first to demonstrate that repeated TGZ doses can upregulate Cyp7A1 in rats. Copyright © 2017 by The American Society for Pharmacology and Experimental Therapeutics.

  1. Development of an efficient agrobacterium-mediated gene targeting system for rice and analysis of rice knockouts lacking granule-bound starch synthase (Waxy) and β1,2-xylosyltransferase.

    Science.gov (United States)

    Ozawa, Kenjirou; Wakasa, Yuhya; Ogo, Yuko; Matsuo, Kouki; Kawahigashi, Hiroyuki; Takaiwa, Fumio

    2012-04-01

    We have developed a high-frequency method for Agrobacterium-mediated gene targeting by combining an efficient transformation system using rice suspension-cultured calli and a positive/negative selection system. Compared with the conventional transformation system using calli on solid medium, transformation using suspension-cultured calli resulted in a 5- to 10-fold increase in the number of resistant calli per weight of starting material after positive/negative selection. Homologous recombination occurred in about 1.5% of the positive/negative selected calli. To evaluate the efficacy of our method, we show in this report that knockout rice plants containing either a disrupted Waxy (granule-bound starch synthase) or a disrupted Xyl (β1,2-xylosyltransferase) gene can be easily obtained by homologous recombination. Study of gene function using homologous recombination in higher plants can now be considered routine work as a direct result of this technical advance.

  2. Random Splicing of Several Exons Caused by a Single Base Change in the Target Exon of CRISPR/Cas9 Mediated Gene Knockout

    Directory of Open Access Journals (Sweden)

    Marcel Kapahnke

    2016-12-01

    Full Text Available The clustered regularly interspaced short palindromic repeats (CRISPR-associated sequence 9 (CRISPR/Cas9 system is widely used for genome editing purposes as it facilitates an efficient knockout of a specific gene in, e.g. cultured cells. Targeted double-strand breaks are introduced to the target sequence of the guide RNAs, which activates the cellular DNA repair mechanism for non-homologous-end-joining, resulting in unprecise repair and introduction of small deletions or insertions. Due to this, sequence alterations in the coding region of the target gene frequently cause frame-shift mutations, facilitating degradation of the mRNA. We here show that such CRISPR/Cas9-mediated alterations in the target exon may also result in altered splicing of the respective pre-mRNA, most likely due to mutations of splice-regulatory sequences. Using the human FLOT-1 gene as an example, we demonstrate that such altered splicing products also give rise to aberrant protein products. These may potentially function as dominant-negative proteins and thus interfere with the interpretation of the data generated with these cell lines. Since most researchers only control the consequences of CRISPR knockout at genomic and protein level, our data should encourage to also check the alterations at the mRNA level.

  3. Studies of an Androgen-Binding Protein Knockout Corroborate a Role for Salivary ABP in Mouse Communication.

    Science.gov (United States)

    Chung, Amanda G; Belone, Phillip M; Vošlajerová Bímová, Barbora; Karn, Robert M; Laukaitis, Christina M

    2017-02-03

    The house mouse Androgen-binding protein (Abp) gene family is comprised of 64 paralogs, 30 Abpa and 34 Abpbg, encoding the alpha (ABPA) and betagamma (ABPBG) protein subunits that are disulfide-bridged to form dimers in secretions. Only 14 Abp genes are expressed in distinct patterns in the lacrimal (11) and submandibular glands (3). We created a knockout mouse line lacking two of the three genes expressed in submandibular glands, Abpa27 and Abpbg27, by replacing them with the neomycin resistance gene. The knockout genotype (-/-) showed no Abpa27 or Abpbg27 transcripts in submandibular gland cDNA libraries and there was a concomitant lack of protein expression of ABPA27 and ABPBG27 in the -/- genotype saliva, shown by elimination of these two proteins from the saliva proteome and the loss of cross-reactive material in the acinar cells of the submandibular glands. We also observed a decrease in BG26 protein in the -/- animals, suggesting monomer instability. Overall, we observed no major phenotypic changes in the -/- genotype, compared with their +/+ and +/- siblings raised in a laboratory setting, including normal growth curves, tissue histology, fecundity and longevity. The only difference is that male and female C57BL/6 mice preferred saliva of the opposite sex containing ABP statistically significantly more than saliva of the opposite sex without ABP in a Y-maze test. These results show for the first time that mice can sense the presence of ABP between saliva targets with and without ABPs, and that they spend more time investigating the target containing ABP.

  4. 变形链球菌gcp基因敲除菌株表达谱基因芯片*☆%Streptococcus mutans gcp gene knockout strains expression profile gene chip

    Institute of Scientific and Technical Information of China (English)

    谢苗苗; 胡晓聪; 吴补领; 闫文娟

    2013-01-01

    BACKGROUND:Previous studies have confirmed the presence of bis-(3'-5')-cyclic dimeric guanosine monophosphate signaling pathway in Streptococcus mutans, which construct the streptococcus mutans gcp gene knockout strains. OBJECTIVE:To compare the gene expression differences between Streptococcus mutans wild strains and gcp mutant strains, and to screen the biofilm-related genes from them for the fol ow-up study. METHODS:The total RNA of two kinds of strains were extracted and stained with cy3 and cy5 respectively after reverse transcription. The gene chip was scanned after hybridization and the differential gene were obtained through the data analysis. The different expression genes were verified by real-time PCR. RESULTS AND CONCLUSION:Differential genes were mainly relative about glucose metabolism and biofilm formation. We selected two genes for real-time PCR verification. The PCR results were consistent with the microarray results. After Streptococcus mutans gcp gene knockout, the gene expressions of gcp mutant strains were upregulated and the gene expressions of phosphotransferase system were downregulated, this result suggested that two different genes were related with the c-di-GMP signal pathway downstream.%  背景:前期研究中经证实变形链球菌内部存在单磷酸鸟苷环二聚体信号通路,构建了变形链球菌gcp基因敲除菌株。  目的:比较变形链球菌野生菌种和gcp基因突变菌株基因表达的差异情况,筛选与生物膜相关的基因,进入后续研究。  方法:提取两种细菌的总RNA,反转录后分别用cy3和cy5染色。与基因芯片杂交后,扫描结果,进行数据分析,获取差异基因信息,对筛选的基因进行Real-Time PCR验证。  结果与结论:差异基因主要与糖代谢、生物膜形成有关,选择了2个基因进行验证,PCR结果与芯片结果相符合。变形链球菌gcp基因敲除后,突变菌株ahpC基因表达

  5. Gene Knockout Shows That PML (TRIM19) Does Not Restrict the Early Stages of HIV-1 Infection in Human Cell Lines.

    Science.gov (United States)

    Masroori, Nasser; Cherry, Pearl; Merindol, Natacha; Li, Jia-Xin; Dufour, Caroline; Poulain, Lina; Plourde, Mélodie B; Berthoux, Lionel

    2017-01-01

    unambiguous, knockout-based evidence that PML does not restrict the early postentry stages of HIV-1 infection in a variety of human cell types and does not participate in the inhibition of HIV-1 by IFN-I. Although this study does not exclude the possibility of other mechanisms by which PML may interfere with HIV-1, we nonetheless demonstrate that PML does not generally act as an HIV-1 restriction factor in human cells and that its presence is not required for IFN-I to stimulate the expression of anti-HIV-1 genes. These results contribute to uncovering the landscape of HIV-1 inhibition by ISGs in human cells.

  6. Hormone-Sensitive Lipase Knockouts

    Directory of Open Access Journals (Sweden)

    Shen Wen-Jun

    2006-02-01

    Full Text Available Abstract All treatments for obesity, including dietary restriction of carbohydrates, have a goal of reducing the storage of fat in adipocytes. The chief enzyme responsible for the mobilization of FFA from adipose tissue, i.e., lipolysis, is thought to be hormone-sensitive lipase (HSL. Studies of HSL knockouts have provided important insights into the functional significance of HSL and into adipose metabolism in general. Studies have provided evidence that HSL, though possessing triacylglycerol lipase activity, appears to be the rate-limiting enzyme for cholesteryl ester and diacylglycerol hydrolysis in adipose tissue and is essential for complete hormone stimulated lipolysis, but other triacylglycerol lipases are important in mediating triacylglycerol hydrolysis in lipolysis. HSL knockouts are resistant to both high fat diet-induced and genetic obesity, displaying reduced quantities of white with increased amounts of brown adipose tissue, increased numbers of adipose macrophages, and have multiple alterations in the expression of genes involved in adipose differentiation, including transcription factors, markers of adipocyte differentiation, and enzymes of fatty acid and triglyceride synthesis. With disruption of lipolysis by removal of HSL, there is a drastic reduction in lipogenesis and alteration in adipose metabolism.

  7. Pig gene knockout by rAAV-mediated homologous recombination: comparison of BRCA1 gene knockout efficiency in Yucatan and Göttingen fibroblasts with slightly different target sequences.

    Science.gov (United States)

    Luo, Yonglun; Bolund, Lars; Sørensen, Charlotte Brandt

    2012-06-01

    In this study, we compared the gene targeting efficiencies of two rAAV-BRCA1 KO targeting constructs in Yucatan and Göttingen minipig fibroblasts. The homology arms of the constructs consisted exclusively of exonic sequences amplified by PCR from Yucatan genomic DNA. The sequences were identical to those of the reference porcine genome of a Duroc sow (Ensembl Susscrofa 9) and the BRCA1 gene of the Landrace breed (NCBI acc. no. AB271921). Surprisingly, we found that the very efficient gene targeting observed for Yucatan fibroblasts (35% targeting efficiency) was completely absent using either of the two constructs in Göttingen fibroblasts. Sequencing of the relevant BRCA1 exon 11 region (~2 kb) in the Göttingen minipig revealed three single nucleotide differences in the sequence targeted by the left homology arm of the construct (0.3% of the bases) and three or seven in the two right homology regions (0.3 or 0.7% of the bases, respectively). Construction of a novel rAAV-BRCA1 targeting vector based on the Göttingen genomic DNA sequence re-established gene targeting although the efficiency was somewhat lower than that observed for Yucatan fibroblasts. These BRCA1 KO Göttingen fibroblast clones have been used as nuclear donor cells for somatic cell nuclear transfer to generate a Göttingen BRCA1 KO pig model as previously done with the Yucatan breed. The present study illustrates that even a few mismatches present in the homology arms of an efficient rAAV-targeting construct can completely abolish gene targeting by homologous recombination emphasizing the importance of using isogenic DNA even for creating targeting constructs consisting of exon sequences only.

  8. Tempol improves lipid profile and prevents left ventricular hypertrophy in LDL receptor gene knockout (LDLr-/-) mice on a high-fat diet.

    Science.gov (United States)

    Viana Gonçalves, Igor Cândido; Cerdeira, Cláudio Daniel; Poletti Camara, Eduardo; Dias Garcia, José Antônio; Ribeiro Pereira Lima Brigagão, Maísa; Bessa Veloso Silva, Roberta; Bitencourt Dos Santos, Gérsika

    2017-09-01

    Dyslipidemia is associated with increased risk of cardiovascular disease and atherosclerosis, and hence with high morbidity and mortality. This study investigated the effects of the nitroxide 4-hydroxy-2,2,6,6-tetramethylpiperidine 1-oxyl (Tempol) on lipid profile and cardiac morphology in low-density lipoprotein (LDL) receptor gene knockout (LDLr-/-) mice. Male LDLr-/- mice (three months old, approximately 22 g weight) were divided into the following groups: controls, including (1) standard chow (SC, n=8) and (2) high-fat diet (HFD, n=8); and treatment, including (3) standard chow + Tempol (SC+T, n=8) (30 mg/kg administered by gavage, once daily) and (4) high-fat diet + Tempol (HFD+T, n=8) (30 mg/kg). After 30 days of the diet/treatment, whole blood was collected for analysis of biochemical parameters (total cholesterol, triglycerides [TG], high-density lipoprotein [HDL], LDL, and very low-density lipoprotein [VLDL]). The heart was removed through thoracotomy and histological analysis of the left ventricle was performed. A significant increase in TG, LDL, and VLDL and marked left ventricular hypertrophy (LVH) were demonstrated in the HFD group relative to the SC group (p<0.05), while Tempol treatment (HFD+T group) significantly (p<0.05) prevented increases in the levels of these lipid profile markers and attenuated LVH compared with the HFD group. In this study, Tempol showed potential for the prevention of events related to serious diseases of the cardiovascular system. Copyright © 2017 Sociedade Portuguesa de Cardiologia. Publicado por Elsevier España, S.L.U. All rights reserved.

  9. Isospin symmetry at high spin studied via nucleon knockout from isomeric states

    OpenAIRE

    2016-01-01

    One-neutron knockout reactions have been performed on a beam of radioactive 53Co in a high-spin isomeric state. The analysis is shown to yield highly-selective population of high-spin states in an exotic nucleus with a significant cross section, and hence represents a technique that is applicable to the planned new generation of fragmentation-based radioactive beam facilities. Additionally, the relative cross sections among the excited states can be predicted to a high level of accuracy when ...

  10. Breeding Reproducing and Identifying for p53 Gene Knockout Mice%p53基因敲除小鼠的饲养繁殖及鉴定

    Institute of Scientific and Technical Information of China (English)

    乔录新; 徐萌; 柴梦音; 乔欣; 陈德喜

    2012-01-01

    目的 为了繁育和鉴定p53基因敲除小鼠,将引进的杂合子小鼠进行饲养繁殖,杂合子用于继续保种.方法 对其幼鼠剪尾提取基因组DNA,采用PCR方法进行基因型鉴定.结果 对引进小鼠已成功饲养和繁殖,并得到纯合基因缺失型小鼠.结论 正确的饲养、繁殖及基因鉴定方法对于基因敲除小鼠的获得和保种具有重要的意义.%Objective To breed and identify p53 gene knockout mice, Heterozygote mice were bred and reproduced. Methods Genome DNA extracted from the mice' s tails were subjected to PCR test for genotype identification. Results Heterozygous were used to acquire baby mice for Protection species. Conclusion The breeding and reproducing were successful and Homozygous genotype mice were acquired. Appropriate methods of feeding, breeding and identifying are important for obtaining gene knockout mice and protecting species.

  11. Accumulation of (5′S)-8,5′-cyclo-2′-deoxyadenosine in organs of Cockayne syndrome complementation group B gene knockout mice

    Science.gov (United States)

    Kirkali, Güldal; de Souza-Pinto, Nadja C.; Jaruga, Pawel; Bohr, Vilhelm A.; Dizdaroglu, Miral

    2009-01-01

    Cockayne syndrome (CS) is a human genetic disorder characterized by sensitivity to UV radiation, neurodegeneration, premature aging among other phenotypes. CS complementation group B (CS-B) gene (csb) encodes the CSB protein (CSB) that is involved in base excision repair of a number of oxidatively induced lesions in genomic DNA in vivo. We hypothesized that CSB may also play a role in cellular repair of the DNA helix-distorting tandem lesion (5′S)-8,5′-cyclo-2′-deoxyadenosine (S-cdA). Among many DNA lesions, S-cdA is unique in that it represents a concomitant damage to both the sugar and base moieties of the same nucleoside. Because of the presence of the C8-C5′ covalent bond, S-cdA is repaired by nucleotide excision repair unlike most of other oxidatively induced lesions in DNA, which are subject to base excision repair. To test our hypothesis, we isolated genomic DNA from brain, kidney and liver of wild type and csb knockout (csb-/-) mice. Animals were not exposed to any exogenous oxidative stress before the experiment. DNA samples were analysed by liquid chromatography/mass spectrometry with isotope-dilution. Statistically greater background levels of S-cdA were observed in all three organs of csb-/- mice than in those of wild type mice. These results suggest the in vivo accumulation of S-cdA in genomic DNA due to lack of its repair in csb-/- mice. Thus, this study provides, for the first time, the evidence that CSB plays a role in the repair of the DNA helix-distorting tandem lesion S-cdA. Accumulation of unrepaired S-cdA in vivo may contribute to the pathology associated with CS. PMID:18992371

  12. 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 abs

  13. Knockout of GH3 genes in the moss Physcomitrella patens leads to increased IAA levels at elevated temperature and in darkness.

    Science.gov (United States)

    Mittag, Jennifer; Gabrielyan, Anastasia; Ludwig-Müller, Jutta

    2015-12-01

    Two proteins of the GRETCHEN HAGEN3 (GH3) family of acyl acid amido synthetases from the moss Physcomitrella patens conjugate indole-3-acetic acid (IAA) to a series of amino acids. The possible function of altered auxin levels in the moss in response to two different growth perturbations, elevated temperatures and darkness, was analyzed using a) the recently described double knockout lines in both P. patens GH3 genes (GH3-doKO) and b) a previously characterized line harboring an auxin-inducible soybean GH3 promoter::reporter fused to β-glucuronidase (G1-GUS). The GUS activity as marker of the auxin response increased at higher temperatures and after cultivation in the darkness for a period of up to four weeks. Generally, the double knockout plants grew more slowly than the wild type (WT). The altered growth conditions influenced the phenotypes of the double knockout lines differently from that of WT moss. Higher temperatures negatively affected GH3-doKO plants compared to WT which was shown by stronger loss of chlorophyll. On the other hand, a positive effect was found on the concentrations of free IAA which increased at 28 °C in the GH3-doKO lines compared to WT plants. A different factor, namely darkness vs. a light/dark cycle caused the adverse phenotype concerning chlorophyll concentrations. Mutant moss plants showed higher chlorophyll concentrations than WT and these correlated with higher free IAA in the plant population that was classified as green. Our data show that growth perturbations result in higher free IAA levels in the GH3-doKO mutants, but in one case - growth in darkness - the mutants could cope better with the condition, whereas at elevated temperatures the mutants were more sensitive than WT. Thus, GH3 function in P. patens WT could lie in the regulation of IAA concentrations under unfavorable environmental conditions.

  14. Experimental study of the knockout reaction mechanism using O14 at 60 MeV/nucleon

    Science.gov (United States)

    Sun, Y. L.; Lee, J.; Ye, Y. L.; Obertelli, A.; Li, Z. H.; Aoi, N.; Ong, H. J.; Ayyad, Y.; Bertulani, C. A.; Chen, J.; Corsi, A.; Cappuzzello, F.; Cavallaro, M.; Furono, T.; Ge, Y. C.; Hashimoto, T.; Ideguchi, E.; Kawabata, T.; Lou, J. L.; Li, Q. T.; Lorusso, G.; Lu, F.; Liu, H. N.; Nishimura, S.; Suzuki, H.; Tanaka, J.; Tanaka, M.; Tran, D. T.; Tsang, M. B.; Wu, J.; Xu, Z. Y.; Yamamoto, T.

    2016-04-01

    Background: For the deeply bound one-nucleon removal at intermediate energies using a Be9 or C12 target, a strong reduction of cross section was observed relative to the prediction of eikonal theoretical model. The large disagreement has not been explained and the systematic trend is inconsistent with results from transfer reactions. The recently observed asymmetric parallel momentum distribution of the knockout residue indicates the significant dissipative core-target interaction in the knockout reaction with a composite target, implying new reaction mechanisms beyond the eikonal reaction descriptions. Purpose: To investigate the reaction mechanism for deeply bound nucleon removal at intermediate energies. Method: Neutron removal from O14 using a C12 target at 60 MeV/nucleon was performed. Nucleon knockout cross sections were measured. The unbound excited states of O13 were reconstructed by using the invariant mass method with the residues and the associated decay protons measured in coincidence. The measured cross sections are compared with an intra-nuclear cascade (INC) prediction. Results: The measured cross section of (O14C11,) is 60(9) mb, which is 3.5 times larger than that of (O14O13,) channel. This 2 p n -removal cross section is consistent with INC prediction, which is 66 mb with the main contribution being non-direct reaction processes. On the other hand, the upper limit of the cross section for one-neutron removal from O14 followed by proton evaporation is 4.6(20) mb, integrated up to 6 MeV above the proton separation energy of O13 . The calculated total cross section for such reaction processes by the INC model is 2.5 mb, which is within the measured upper limit. Conclusions: The data provide the first constraint on the role of core excitation and evaporation processes in deeply bound nucleon removal from asymmetric nuclei. The experiment results suggest that non-direct reaction processes, which are not considered in the eikonal model, play an

  15. Effect of hyperlipidemia on the expression of circadian genes in apolipoprotein E knock-out atherosclerotic mice

    Directory of Open Access Journals (Sweden)

    Chen Sifeng

    2009-12-01

    Full Text Available Abstract Background Circadian patterns of cardiovascular vulnerability were well characterized, with a peak incidence of acute myocardial infarction and stroke secondary to atherosclerosis in the morning, which showed the circadian clock may take part in the pathological process of atherosclerosis induced by hyperlipidemia. Hence, the effect of hyperlipidemia on the expression of circadian genes was investigated in atherosclerotic mouse model. Results In apoE-/-mice on regular chow or high-fat diet, an atherosclerotic mouse model induced by heperlipidemia, we found that the peak concentration of serum lipids was showed four or eight hours later in apoE-/- mice, compared to C57BL/6J mice. During the artificial light period, a reduce in circulating level of serum lipids corresponded with the observed increase of the expression levels of some the transcription factors involved in lipid metabolism, such as PPARα and RXRα. Meanwhile, the expression of circadian genes was changed following with amplitude reduced or the peak mRNA level delayed. Conclusions Our studies indicated that heperlipidemia altered both the rhythmicity and expression of circadian genes. Diet-induced circadian disruption may affect the process of atherosclerosis and some acute cardiovascular disease.

  16. Generation of a conditional knockout of murine glucocerebrosidase: utility for the study of Gaucher disease.

    Science.gov (United States)

    Sinclair, Graham B; Jevon, Gareth; Colobong, Karen E; Randall, Derrick R; Choy, Francis Y M; Clarke, Lorne A

    2007-02-01

    Gaucher disease is a disorder of sphingolipid metabolism resulting from an inherited deficiency of the lysosomal hydrolase glucocerebrosidase. Affected individuals present with a spectrum of clinical symptoms ranging from hepatosplenomegaly, haematological abnormalities, and bone pain in type 1 disease, to severe neurodegeneration and premature death in types 2 and 3 disease. Although the basic biochemical defect is well characterized, there remains a poor understanding of the underlying pathophysiology of disease. In vitro studies suggest that macrophage glucocerebroside storage leads to tissue dysfunction through complex mechanisms involving altered intracellular calcium homeostasis and apoptosis. In order to study the pathogenic roles of these complex interactions, a viable animal model for Gaucher disease is needed. The complexity of this single gene disorder has been emphasized by the varied results of previous murine Gaucher models, ranging from perinatal lethality to phenotypically and biochemically asymptomatic animals. Recognizing the need to modulate the biochemical phenotype in mice to produce a relevant model, we have created a murine strain with key exons of the glucocerebrosidase gene flanked by loxP sites. We show that expression of Cre-recombinase in cells of hematopoietic and endothelial origin results in deficiency of glucocerebrosidase in the liver, spleen, bone marrow, and peripheral white cells. Glucocerebroside storage in this model leads to progressive splenomegaly with Gaucher cell infiltration and modest storage in the liver by 26 weeks of age. These results indicate the utility of this loxP GBA targeted murine strain for understanding the complex pathophysiology of Gaucher disease.

  17. Smad3基因剔除小鼠的基因型鉴定与繁殖性能研究%Research of the Genotype Identification and Riproductive Performance of Smad3 Gene Knockout Mice

    Institute of Scientific and Technical Information of China (English)

    孙岩松; 吕雅歆; 王冬平; 方厚华; 时彦胜; 战大伟; 张爱兰; 李桂军

    2003-01-01

    The previous study of Srnad3 gene knockout mice ( Smad3ex8/ex8 ) shows that the Smad3ex8/ex8 mice develop progressive leukocytosis, periodontitis, gastritis, colitis and chronic infection with abscess formation adjacent to mucosal surfaces . symptomatic mutant mice exhibit thymic involution, enlarged lymph nodes and T cells with activated phenotype.Further study suggests that the thymic cells and peripheral T ceels of Smad3ex8/ex8 mice have lost the response to TGF-β.Furthermore, nwe found that the homologous Smad3ex8/ex mice developed degenerative joint disease resembling human osteoarthritis, osteoporosis and wound healing up quicker. So the mice can serve as an ideal animal model for immune dysregulation, osteoarthritis and so on.

  18. Knock-out of SO1377 gene, which encodes the member of a conserved hypothetical bacterial protein family COG2268, results in alteration of iron metabolism, increased spontaneous mutation and hydrogen peroxide sensitivity in Shewanella oneidensis MR-1

    Directory of Open Access Journals (Sweden)

    Klingeman Dawn M

    2006-04-01

    Full Text Available Abstract Background Shewanella oneidensis MR-1 is a facultative, gram-negative bacterium capable of coupling the oxidation of organic carbon to a wide range of electron acceptors such as oxygen, nitrate and metals, and has potential for bioremediation of heavy metal contaminated sites. The complete 5-Mb genome of S. oneidensis MR-1 was sequenced and standard sequence-comparison methods revealed approximately 42% of the MR-1 genome encodes proteins of unknown function. Defining the functions of hypothetical proteins is a great challenge and may need a systems approach. In this study, by using integrated approaches including whole genomic microarray and proteomics, we examined knockout effects of the gene encoding SO1377 (gi24372955, a member of the conserved, hypothetical, bacterial protein family COG2268 (Clusters of Orthologous Group in bacterium Shewanella oneidensis MR-1, under various physiological conditions. Results Compared with the wild-type strain, growth assays showed that the deletion mutant had a decreased growth rate when cultured aerobically, but not affected under anaerobic conditions. Whole-genome expression (RNA and protein profiles revealed numerous gene and protein expression changes relative to the wild-type control, including some involved in iron metabolism, oxidative damage protection and respiratory electron transfer, e. g. complex IV of the respiration chain. Although total intracellular iron levels remained unchanged, whole-cell electron paramagnetic resonance (EPR demonstrated that the level of free iron in mutant cells was 3 times less than that of the wild-type strain. Siderophore excretion in the mutant also decreased in iron-depleted medium. The mutant was more sensitive to hydrogen peroxide and gave rise to 100 times more colonies resistant to gentamicin or kanamycin. Conclusion Our results showed that the knock-out of SO1377 gene had pleiotropic effects and suggested that SO1377 may play a role in iron

  19. Establishment of Immortalized BMP2/4 Double Knock-Out Osteoblastic Cells Is Essential for Study of Osteoblast Growth, Differentiation, and Osteogenesis.

    Science.gov (United States)

    Wu, Li-An; Wang, Feng; Donly, Kevin J; Baker, Andrew; Wan, Chunyan; Luo, Daoshu; MacDougall, Mary; Chen, Shuo

    2016-06-01

    Bone morphogenetic proteins 2 and 4 (BMP2/4) are essential for osteoblast differentiation and osteogenesis. Generation of a BMP2/4 dual knock-out ((ko/ko)) osteoblastic cell line is a valuable asset for studying effects of BMP2/4 on skeletal development. In this study, our goal was to create immortalized mouse deleted BMP2/4 osteoblasts by infecting adenoviruses with Cre recombinase and green fluorescent protein genes into immortalized murine floxed BMP2/4 osteoblasts. Transduced BMP2/4(ko/ko) cells were verified by green immunofluorescence and PCR. BMP2/4(ko/ko) osteoblasts exhibited small size, slow cell proliferation rate and cell growth was arrested in G1 and G2 phases. Expression of bone-relate genes was reduced in the BMP2/4(ko/ko) cells, resulting in delay of cell differentiation and mineralization. Importantly, extracellular matrix remodeling was impaired in the BMP2/4(ko/ko) osteoblasts as reflected by decreased Mmp-2 and Mmp-9 expressions. Cell differentiation and mineralization were rescued by exogenous BMP2 and/or BMP4. Therefore, we for the first time described establishment of an immortalized deleted BMP2/4 osteoblast line useful for study of mechanisms in regulating osteoblast lineages.

  20. Cas-Database: web-based genome-wide guide RNA library design for gene knockout screens using CRISPR-Cas9.

    Science.gov (United States)

    Park, Jeongbin; Kim, Jin-Soo; Bae, Sangsu

    2016-07-01

    CRISPR-derived RNA guided endonucleases (RGENs) have been widely used for both gene knockout and knock-in at the level of single or multiple genes. RGENs are now available for forward genetic screens at genome scale, but single guide RNA (sgRNA) selection at this scale is difficult. We develop an online tool, Cas-Database, a genome-wide gRNA library design tool for Cas9 nucleases from Streptococcus pyogenes (SpCas9). With an easy-to-use web interface, Cas-Database allows users to select optimal target sequences simply by changing the filtering conditions. Furthermore, it provides a powerful way to select multiple optimal target sequences from thousands of genes at once for the creation of a genome-wide library. Cas-Database also provides a web application programming interface (web API) for advanced bioinformatics users. Free access at http://www.rgenome.net/cas-database/ sangsubae@hanyang.ac.kr or jskim01@snu.ac.kr Supplementary data are available at Bioinformatics online. © The Author 2016. Published by Oxford University Press.

  1. A Simplified Method for Gene Knockout and Direct Screening of Recombinant Clones for Application in Paenibacillus polymyxa.

    Directory of Open Access Journals (Sweden)

    Seong-Bin Kim

    Full Text Available Paenibacillus polymyxa is a bacterium widely used in agriculture, industry, and environmental remediation because it has multiple functions including nitrogen fixation and produces various biologically active compounds. Among these compounds are the antibiotics polymyxins, and the bacterium is currently being reassessed for medical application. However, a lack of genetic tools for manipulation of P. polymyxa has limited our understanding of the biosynthesis of these compounds.To facilitate an understanding of the genetic determinants of the bacterium, we have developed a system for marker exchange mutagenesis directly on competent cells of P. polymyxa under conditions where homologous recombination is enhanced by denaturation of the suicide plasmid DNA. To test this system, we targeted P. polymyxa α-and β-amylase genes for disruption. Chloramphenicol or erythromycin resistance genes were inserted into the suicide plasmid pGEM7Z-f+ (Promega. To mediate homologous recombination and replacement of the targeted genes with the antibiotic resistance genes nucleotide sequences of the α-and β-amylase genes were cloned into the plasmid flanking the antibiotic resistance genes.We have created a simple system for targeted gene deletion in P. polymyxa E681. We propose that P. polymyxa isogenic mutants could be developed using this system of marker exchange mutagenesis. α-and β-amylase genes provide a useful tool for direct recombinant screening in P. polymyxa.

  2. Generation of conditional knockout alleles for PRL-3.

    Science.gov (United States)

    Yan, Hong; Kong, Dong; Ge, Xiaomei; Gao, Xiang; Han, Xiao

    2011-11-01

    Phosphatase of regenerating liver-3 (PRL-3) is a member of the protein tyrosine phosphatase (PTP) superfamily and is highly expressed in cancer metastases. For better understanding of the role of PRL-3 in tumor metastasis, we applied a rapid and efficient method for generating PRL-3 floxed mice and investigated its phenotypes. A BAC retrieval strategy was applied to construct the PRL-3 conditional gene-targeting vector. Exon 4 was selected for deletion to generate a nonfunctional prematurely terminated short peptide as it will cause a frame-shift mutation. Conditional knockout PRL-3 mice were generated by using the Cre-loxP system and were validated by Southern blot and RT-PCR analysis. Further analysis revealed the phenotype characteristics of PRL-3 knockout mice and wildtype mice. In this study, we successfully constructed the PRL-3 conditional knockout mice, which will be helpful to clarify the roles of PRL-3 and the mechanisms in tumor metastasis.

  3. Cognitive and socio-emotional deficits in platelet-derived growth factor receptor-β gene knockout mice.

    Directory of Open Access Journals (Sweden)

    Phuong Thi Hong Nguyen

    Full Text Available Platelet-derived growth factor (PDGF is a potent mitogen. Extensive in vivo studies of PDGF and its receptor (PDGFR genes have reported that PDGF plays an important role in embryogenesis and development of the central nervous system (CNS. Furthermore, PDGF and the β subunit of the PDGF receptor (PDGFR-β have been reported to be associated with schizophrenia and autism. However, no study has reported on the effects of PDGF deletion on mice behavior. Here we generated novel mutant mice (PDGFR-β KO in which PDGFR-β was conditionally deleted in CNS neurons using the Cre/loxP system. Mice without the Cre transgene but with floxed PDGFR-β were used as controls. Both groups of mice reached adulthood without any apparent anatomical defects. These mice were further examined by conducting several behavioral tests for spatial memory, social interaction, conditioning, prepulse inhibition, and forced swimming. The test results indicated that the PDGFR-β KO mice show deficits in all of these areas. Furthermore, an immunohistochemical study of the PDGFR-β KO mice brain indicated that the number of parvalbumin (calcium-binding protein-positive (i.e., putatively γ-aminobutyric acid-ergic neurons was low in the amygdala, hippocampus, and medial prefrontal cortex. Neurophysiological studies indicated that sensory-evoked gamma oscillation was low in the PDGFR-β KO mice, consistent with the observed reduction in the number of parvalbumin-positive neurons. These results suggest that PDGFR-β plays an important role in cognitive and socioemotional functions, and that deficits in this receptor may partly underlie the cognitive and socioemotional deficits observed in schizophrenic and autistic patients.

  4. Ins1 Gene Up-Regulated in a β-Cell Line Derived from Ins2 Knockout Mice

    OpenAIRE

    2003-01-01

    The authors have derived a new β-cell line (βIns2−/−lacZ) from Ins2−/− mice that carry the lacZ reporter gene under control of the Ins2 promoter. βIns2−/−lacZ cells stained positively using anti-insulin antibody, expressed β-cell–specific genes encoding the transcription factor PDX-1, glucokinase, and Glut-2, retained glucose-responsiveness for insulin secretion, and expressed the lacZ gene. Analysis of Ins1 expression by reverse transcriptase–polymerase chain reaction (RT-PCR) showed that In...

  5. Ultra-superovulation for the CRISPR-Cas9-mediated production of gene-knockout, single-amino-acid-substituted, and floxed mice

    Science.gov (United States)

    Nakagawa, Yoshiko; Nishimichi, Norihisa; Yokosaki, Yasuyuki; Yanaka, Noriyuki; Takeo, Toru; Nakagata, Naomi; Yamamoto, Takashi

    2016-01-01

    ABSTRACT Current advances in producing genetically modified mice using genome-editing technologies have indicated the need for improvement of limiting factors including zygote collection for microinjection and their cryopreservation. Recently, we developed a novel superovulation technique using inhibin antiserum and equine chorionic gonadotropin to promote follicle growth. This method enabled the increased production of fertilized oocytes via in vitro fertilization compared with the conventional superovulation method. Here, we verify that the ultra-superovulation technique can be used for the efficient generation of clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR-associated protein 9 (Cas9)-mediated knockout mice by microinjection of plasmid vector or ribonucleoprotein into zygotes. We also investigated whether single-amino-acid-substituted mice and conditional knockout mice could be generated. Founder mice bearing base substitutions were generated more efficiently by co-microinjection of Cas9 protein, a guide RNA and single-stranded oligodeoxynucleotide (ssODN) than by plasmid microinjection with ssODN. The conditional allele was successfully introduced by the one-step insertion of an ssODN designed to carry an exon flanked by two loxP sequences and homology arms using a double-cut CRISPR-Cas9 strategy. Our study presents a useful method for the CRISPR-Cas9-based generation of genetically modified mice from the viewpoints of animal welfare and work efficiency. PMID:27387532

  6. Ultra-superovulation for the CRISPR-Cas9-mediated production of gene-knockout, single-amino-acid-substituted, and floxed mice

    Directory of Open Access Journals (Sweden)

    Yoshiko Nakagawa

    2016-08-01

    Full Text Available Current advances in producing genetically modified mice using genome-editing technologies have indicated the need for improvement of limiting factors including zygote collection for microinjection and their cryopreservation. Recently, we developed a novel superovulation technique using inhibin antiserum and equine chorionic gonadotropin to promote follicle growth. This method enabled the increased production of fertilized oocytes via in vitro fertilization compared with the conventional superovulation method. Here, we verify that the ultra-superovulation technique can be used for the efficient generation of clustered regularly interspaced short palindromic repeats (CRISPR-CRISPR-associated protein 9 (Cas9-mediated knockout mice by microinjection of plasmid vector or ribonucleoprotein into zygotes. We also investigated whether single-amino-acid-substituted mice and conditional knockout mice could be generated. Founder mice bearing base substitutions were generated more efficiently by co-microinjection of Cas9 protein, a guide RNA and single-stranded oligodeoxynucleotide (ssODN than by plasmid microinjection with ssODN. The conditional allele was successfully introduced by the one-step insertion of an ssODN designed to carry an exon flanked by two loxP sequences and homology arms using a double-cut CRISPR-Cas9 strategy. Our study presents a useful method for the CRISPR-Cas9-based generation of genetically modified mice from the viewpoints of animal welfare and work efficiency.

  7. Ultra-superovulation for the CRISPR-Cas9-mediated production of gene-knockout, single-amino-acid-substituted, and floxed mice.

    Science.gov (United States)

    Nakagawa, Yoshiko; Sakuma, Tetsushi; Nishimichi, Norihisa; Yokosaki, Yasuyuki; Yanaka, Noriyuki; Takeo, Toru; Nakagata, Naomi; Yamamoto, Takashi

    2016-08-15

    Current advances in producing genetically modified mice using genome-editing technologies have indicated the need for improvement of limiting factors including zygote collection for microinjection and their cryopreservation. Recently, we developed a novel superovulation technique using inhibin antiserum and equine chorionic gonadotropin to promote follicle growth. This method enabled the increased production of fertilized oocytes via in vitro fertilization compared with the conventional superovulation method. Here, we verify that the ultra-superovulation technique can be used for the efficient generation of clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR-associated protein 9 (Cas9)-mediated knockout mice by microinjection of plasmid vector or ribonucleoprotein into zygotes. We also investigated whether single-amino-acid-substituted mice and conditional knockout mice could be generated. Founder mice bearing base substitutions were generated more efficiently by co-microinjection of Cas9 protein, a guide RNA and single-stranded oligodeoxynucleotide (ssODN) than by plasmid microinjection with ssODN. The conditional allele was successfully introduced by the one-step insertion of an ssODN designed to carry an exon flanked by two loxP sequences and homology arms using a double-cut CRISPR-Cas9 strategy. Our study presents a useful method for the CRISPR-Cas9-based generation of genetically modified mice from the viewpoints of animal welfare and work efficiency.

  8. Novel roles for metallothionein-I + II (MT-I + II) in defense responses, neurogenesis, and tissue restoration after traumatic brain injury: insights from global gene expression profiling in wild-type and MT-I + II knockout mice.

    Science.gov (United States)

    Penkowa, Milena; Cáceres, Mario; Borup, Rehannah; Nielsen, Finn Cilius; Poulsen, Christian Bjørn; Quintana, Albert; Molinero, Amalia; Carrasco, Javier; Florit, Sergi; Giralt, Mercedes; Hidalgo, Juan

    2006-11-15

    Traumatic injury to the brain is one of the leading causes of injury-related death or disability, especially among young people. Inflammatory processes and oxidative stress likely underlie much of the damage elicited by injury, but the full repertoire of responses involved is not well known. A genomic approach, such as the use of microarrays, provides much insight in this regard, especially if combined with the use of gene-targeted animals. We report here the results of one of these studies comparing wild-type and metallothionein-I + II knockout mice subjected to a cryolesion of the somatosensorial cortex and killed at 0, 1, 4, 8, and 16 days postlesion (dpl) using Affymetrix genechips/oligonucleotide arrays interrogating approximately 10,000 different murine genes (MG_U74Av2). Hierarchical clustering analysis of these genes readily shows an orderly pattern of gene responses at specific times consistent with the processes involved in the initial tissue injury and later regeneration of the parenchyma, as well as a prominent effect of MT-I + II deficiency. The results thoroughly confirmed the importance of the antioxidant proteins MT-I + II in the response of the brain to injury and opened new avenues that were confirmed by immunohistochemistry. Data in KO, MT-I-overexpressing, and MT-II-injected mice strongly suggest a role of these proteins in postlesional activation of neural stem cells.

  9. Conditional knockout of tumor overexpressed gene in mouse neurons affects RNA granule assembly, granule translation, LTP and short term habituation.

    Directory of Open Access Journals (Sweden)

    Elisa Barbarese

    Full Text Available In neurons, specific RNAs are assembled into granules, which are translated in dendrites, however the functional consequences of granule assembly are not known. Tumor overexpressed gene (TOG is a granule-associated protein containing multiple binding sites for heterogeneous nuclear ribonucleoprotein (hnRNP A2, another granule component that recognizes cis-acting sequences called hnRNP A2 response elements (A2REs present in several granule RNAs. Translation in granules is sporadic, which is believed to reflect monosomal translation, with occasional bursts, which are believed to reflect polysomal translation. In this study, TOG expression was conditionally knocked out (TOG cKO in mouse hippocampal neurons using cre/lox technology. In TOG cKO cultured neurons granule assembly and bursty translation of activity-regulated cytoskeletal associated (ARC mRNA, an A2RE RNA, are disrupted. In TOG cKO brain slices synaptic sensitivity and long term potentiation (LTP are reduced. TOG cKO mice exhibit hyperactivity, perseveration and impaired short term habituation. These results suggest that in hippocampal neurons TOG is required for granule assembly, granule translation and synaptic plasticity, and affects behavior.

  10. Cloning and knockout of formate hydrogen lyase and H{sub 2}-uptake hydrogenase genes in Enterobacter aerogenes for enhanced hydrogen production

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Hongxin; Ma, Kun; Lu, Yuan; Zhang, Chong; Wang, Liyan; Xing, Xin-Hui [Institute of Biochemical Engineering, Department of Chemical Engineering, Tsinghua University, Tsinghua Yuan, Beijing 100084 (China)

    2009-01-15

    A 5431-bp DNA fragment partially encoding the formate hydrogen lyase (FHL) gene cluster hycABCDE was isolated and identified from Enterobacter aerogenes IAM1183 chromosomal DNA. All the five putative gene products showed a high degree of homology to the reported bacterial FHL proteins. The gene hycA, encoding the FHL repressor protein, and hybO, encoding the small subunit of the uptake hydrogenase, were targeted for genetic knockout for improving the hydrogen production. The pYM-Red recombination system was adopted to form insertional mutations in the E. aerogenes genome, thereby creating mutant strains of IAM1183-A ({delta} hycA), IAM1183-O ({delta} hybO), and IAM1183-AO ({delta} hycA/ {delta} hybO double knockout). The hydrogen production experiments with these mutants showed that the maximum specific hydrogen productivities of IAM1183-A, IAM1183-O, and IAM1183-AO were 2879.466 {+-} 38.59, 2747.203 {+-} 13.25 and 3372.019 {+-} 4.39 (ml h{sup -1} g{sup -1}dry cell weight), respectively, higher than that of the wild strain (2321.861 {+-} 15.34 ml h{sup -1} g{sup -1}dry cell weight). The total H{sub 2} yields by the three mutants IAM1183-A, IAM1183-O and IAM1183-AO were 0.73, 0.78, and 0.83 mol-H{sub 2}/mol glucose, respectively, while the wild-type IAM1183 was only 0.65 mol-H{sub 2}/mol glucose. The metabolites of the mutants including acetate, ethanol, 2,3-butanediol and succinate were all increased compared with that of the wild type, implying the changed metabolic flux by the mutation. In the fermentor cultivation with IAM1183 {delta} hycA/ {delta} hybO, the total hydrogen volume after 16 h cultivation reached 4.4 L, while that for the wild type was only 2.9 L. (author)

  11. The role of histamine in the retina: studies on the Hdc knockout mouse.

    Science.gov (United States)

    Greferath, Ursula; Vessey, Kirstan A; Jobling, Andrew I; Mills, Samuel A; Bui, Bang V; He, Zheng; Nag, Nupur; Ohtsu, Hiroshi; Fletcher, Erica L

    2014-01-01

    The role of histamine in the retina is not well understood, despite it regulating a number of functions within the brain, including sleep, feeding, energy balance, and anxiety. In this study we characterized the structure and function of the retina in mice that lacked expression of the rate limiting enzyme in the formation of histamine, histidine decarboxylase (Hdc-/- mouse). Using laser capture microdissection, Hdc mRNA expression was assessed in the inner and outer nuclear layers of adult C57Bl6J wildtype (WT) and Hdc(-/-)-retinae. In adult WT and Hdc(-/-)-mice, retinal fundi were imaged, retinal structure was assessed using immunocytochemistry and function was probed by electroretinography. Blood flow velocity was assessed by quantifying temporal changes in the dynamic fluorescein angiography in arterioles and venules. In WT retinae, Hdc gene expression was detected in the outer nuclear layer, but not the inner nuclear layer, while the lack of Hdc expression was confirmed in the Hdc-/- retina. Preliminary examination of the fundus and retinal structure of the widely used Hdc-/- mouse strain revealed discrete lesions across the retina that corresponded to areas of photoreceptor abnormality reminiscent of the rd8 (Crb1) mutation. This was confirmed after genotyping and the strain designated Hdcrd8/rd8. In order to determine the effect of the lack of Hdc-alone on the retina, Hdc-/- mice free of the Crb1 mutation were bred. Retinal fundi appeared normal in these animals and there was no difference in retinal structure, macrogliosis, nor any change in microglial characteristics in Hdc-/- compared to wildtype retinae. In addition, retinal function and retinal blood flow dynamics showed no alterations in the Hdc-/- retina. Overall, these results suggest that histamine plays little role in modulating retinal structure and function.

  12. The role of histamine in the retina: studies on the Hdc knockout mouse.

    Directory of Open Access Journals (Sweden)

    Ursula Greferath

    Full Text Available The role of histamine in the retina is not well understood, despite it regulating a number of functions within the brain, including sleep, feeding, energy balance, and anxiety. In this study we characterized the structure and function of the retina in mice that lacked expression of the rate limiting enzyme in the formation of histamine, histidine decarboxylase (Hdc-/- mouse. Using laser capture microdissection, Hdc mRNA expression was assessed in the inner and outer nuclear layers of adult C57Bl6J wildtype (WT and Hdc(-/--retinae. In adult WT and Hdc(-/--mice, retinal fundi were imaged, retinal structure was assessed using immunocytochemistry and function was probed by electroretinography. Blood flow velocity was assessed by quantifying temporal changes in the dynamic fluorescein angiography in arterioles and venules. In WT retinae, Hdc gene expression was detected in the outer nuclear layer, but not the inner nuclear layer, while the lack of Hdc expression was confirmed in the Hdc-/- retina. Preliminary examination of the fundus and retinal structure of the widely used Hdc-/- mouse strain revealed discrete lesions across the retina that corresponded to areas of photoreceptor abnormality reminiscent of the rd8 (Crb1 mutation. This was confirmed after genotyping and the strain designated Hdcrd8/rd8. In order to determine the effect of the lack of Hdc-alone on the retina, Hdc-/- mice free of the Crb1 mutation were bred. Retinal fundi appeared normal in these animals and there was no difference in retinal structure, macrogliosis, nor any change in microglial characteristics in Hdc-/- compared to wildtype retinae. In addition, retinal function and retinal blood flow dynamics showed no alterations in the Hdc-/- retina. Overall, these results suggest that histamine plays little role in modulating retinal structure and function.

  13. Effect of dietary calcium and 1,25-(OH)2D3 on the expression of calcium transport genes in calbindin-D9k and -D28k double knockout mice.

    Science.gov (United States)

    Ko, Sang-Hwan; Choi, Kyung-Chul; Oh, Goo Taeg; Jeung, Eui-Bae

    2009-02-01

    The phenotypes of calbindin-D9k (CaBP-9k) and -28k (CaBP-28k) single knockout (KO) mice are similar to wild-type (WT) mice due to the compensatory action of other calcium transport proteins. In this study, we generated CaBP-9k/CaBP-28k double knockout (DKO) mice in order to investigate the importance of CaBP-9k and CaBP-28k in active calcium processing. Under normal dietary conditions, DKO mice did not exhibit any changes in phenotype or the expression of active calcium transport genes as compared to WT or CaBP-28k KO mice. Under calcium-deficient dietary conditions, the phenotype and expression of calcium transport genes in CaBP-28k KO mice were similar to WT, whereas in DKO mice, serum calcium levels and bone length were decreased. The intestinal and renal expression of transient receptor potential vanilloid member 6 (TRPV6) mRNA was significantly decreased in DKO mice fed a calcium-deficient diet as compared to CaBP-28k KO or WT mice, and DKO mice died after 4 weeks on a calcium-deficient diet. Body weight, bone mineral density (BMD) and bone length were significantly reduced in all mice fed a calcium and 1,25-(OH)(2)D(3)-deficient diet, as compared to a normal diet, and none of the mice survived more than 4 weeks. These results indicate that deletion of CaBP-28k alone does not affect body calcium homeostasis, but that deletion of CaBP-9k and CaBP-28k has a significant effect on calcium processing under calcium-deficient conditions, confirming the importance of dietary calcium and 1,25-(OH)(2)D(3) during growth and development.

  14. Transcriptional regulation of main metabolic pathways of cyoA, cydB, fnr, and fur gene knockout Escherichia coli in C-limited and N-limited aerobic continuous cultures

    Directory of Open Access Journals (Sweden)

    Kumar Rahul

    2011-01-01

    Full Text Available Abstract Background It is important to understand the cellular responses emanating from environmental perturbations to redesign the networks for practical applications. In particular, the carbon (C metabolism, nitrogen (N assimilation, and energy generation are by far important, where those are interconnected and integrated to maintain cellular integrity. In our previous study, we investigated the effect of C/N ratio on the metabolic regulation of gdhA, glnL, glt B,D mutants as well as wild type Escherichia coli (Kumar and Shimizu, MCF, 1-17, 9:8,2010, where it was shown that the transcript levels of cyoA and cydB which encode the terminal oxidases, fnr and fur which encode global regulators were significantly up-regulated under N-limited condition as compared to C-limited condition. In the present study, therefore, the effects of such single-gene knockout on the metabolic regulation were investigated to clarify the roles of those genes in the aerobic continuous culture at the dilution rate of 0.2 h-1. Results The specific glucose consumption rates and the specific CO2 production rates of cyoA, cydB, fnr, and fur mutants were all increased as compared to the wild type under both C-limited and N-limited conditions. The former phenomenon was consistent with the up-regulations of the transcript levels of ptsG and ptsH, which are consistent with down-regulations of crp and mlc genes. Moreover, the increase in the specific glucose consumption rate was also caused by up-regulations of the transcript levels of pfkA, pykF and possibly zwf, where those are consistent with the down regulations of cra, crp and mlc genes. Moreover, the transcript levels of rpoN together with glnK, glnB, glnE were up-regulated, and thus the transcript levels of glnA,L,G, and gltB,D as well as nac were up-regulated, while gdhA was down-regulated. This implies the interconnection between cAMP-Crp and PII-Ntr systems. Moreover, cyoA, cydB, fnr and fur gene deletions up

  15. Generation of Interleukin-2 Receptor Gamma Gene Knockout Pigs from Somatic Cells Genetically Modified by Zinc Finger Nuclease-Encoding mRNA

    Science.gov (United States)

    Watanabe, Masahito; Nakano, Kazuaki; Matsunari, Hitomi; Matsuda, Taisuke; Maehara, Miki; Kanai, Takahiro; Kobayashi, Mirina; Matsumura, Yukina; Sakai, Rieko; Kuramoto, Momoko; Hayashida, Gota; Asano, Yoshinori; Takayanagi, Shuko; Arai, Yoshikazu; Umeyama, Kazuhiro; Nagaya, Masaki; Hanazono, Yutaka; Nagashima, Hiroshi

    2013-01-01

    Zinc finger nuclease (ZFN) is a powerful tool for genome editing. ZFN-encoding plasmid DNA expression systems have been recently employed for the generation of gene knockout (KO) pigs, although one major limitation of this technology is the use of potentially harmful genome-integrating plasmid DNAs. Here we describe a simple, non-integrating strategy for generating KO pigs using ZFN-encoding mRNA. The interleukin-2 receptor gamma (IL2RG) gene was knocked out in porcine fetal fibroblasts using ZFN-encoding mRNAs, and IL2RG KO pigs were subsequently generated using these KO cells through somatic cell nuclear transfer (SCNT). The resulting IL2RG KO pigs completely lacked a thymus and were deficient in T and NK cells, similar to human X-linked SCID patients. Our findings demonstrate that the combination of ZFN-encoding mRNAs and SCNT provides a simple robust method for producing KO pigs without genomic integration. PMID:24130776

  16. A one-step cloning method for the construction of somatic cell gene targeting vectors: application to production of human knockout cell lines

    Directory of Open Access Journals (Sweden)

    Liu Yi

    2012-10-01

    Full Text Available Abstract Background Gene targeting is a powerful method that can be used for examining the functions of genes. Traditionally, the construction of knockout (KO vectors requires an amplification step to obtain two homologous, large fragments of genomic DNA. Restriction enzymes that cut at unique recognitions sites and numerous cloning steps are then carried out; this is often a time-consuming and frustrating process. Results We have developed a one-step cloning method for the insertion of two arms into a KO vector using exonuclease III. We modified an adeno-associated virus KO shuttle vector (pTK-LoxP-NEO-AAV to yield pAAV-LIC, which contained two cassettes at the two multiple-cloning sites. The vector was digested with EcoRV to give two fragments. The two homologous arms, which had an overlap of 16 bases with the ends of the vector fragments, were amplified by polymerase chain reaction. After purification, the four fragments were mixed and treated with exonuclease III, then transformed into Escherichia coli to obtain the desired clones. Using this method, we constructed SirT1 and HDAC2 KO vectors, which were used to establish SirT1 KO cells from the colorectal cancer cell line (HCT116 and HDAC2 KO cells from the colorectal cancer cell line (DLD1. Conclusions Our method is a fast, simple, and efficient technique for cloning, and has great potential for high-throughput construction of KO vectors.

  17. Knockout and identification of the surface antigen 43 gene in escherichia Coli JM109%大肠埃希菌JM109表面抗原 Ag43基因敲除与鉴定

    Institute of Scientific and Technical Information of China (English)

    黄用豪; 赵焕阁; 周松森; 林映莹; 谭光宏; 黄风迎

    2015-01-01

    Objective To knockout and identify the Antigen 43 (Ag43) in the Escherichia Coli JM109 .Methods Mutation group Ⅱ introns RNA protein complexes (RNP) gene sequence was obtained by Sigma Company′s TargeTron Gene Knockout Sys‐tem and Ag43 gene specific designed PCR primers amplification ,then ,to acquired Ag43 specific recombinant RNP plasmid pACD4K‐Ag4 ,this gene sequence was inserted into the plasmid pACD4K‐C of RNA′s expression .Finally ,pEGFP‐Ag43 was trans‐formed into JM109 and inserted the group Ⅱ intron into the Ag43′s locus by IPTG inducing expression .Results The best insertion locus was between 1 812 and 1 913 .Through the agarose electrophoresis gel ,the RNP gene sequence was consistent with the expec‐ted value (350 bp) .The pEGFP‐Ag43 vector was correctly constructed which was proofed by endonuclease Nhe Ⅰ and Hind ⅡI di‐gestion as predicted products (3 646 and 4 029 bp;7 000 and 550 bp ,respectively ) .The PCR and gene sequence results indicated that the group Ⅱ intron was inserted into the locus between 1 812 and 1 913 in the Ag43 gene .Conclusion Successful knockout of the Ag43 in Escherichia Coli JM109 found basis to further study the Ag43′s function and regard the coli as host bacteria of Ag43 chimeric protein recombinant .%目的:敲除大肠埃希菌JM109表面抗原43(Ag43)基因并对其进行鉴定。方法采用Sigma公司的TargeTron基因敲除系统和Ag43基因特异设计的PCR引物扩增获得突变Ⅱ组内含子RNA蛋白复合体(RNP)基因序列,然后将这段基因序插入表达RNP的质粒pACD4K‐C中,获得Ag43特异的重组RNP质粒pACD4K‐Ag43。最后将pACD4K‐Ag43转化JM109,经过IPTG诱导表达将Ⅱ组内含子插入Ag43特异的部位。结果通过软件分析发现插入Ⅱ组内含子的最佳位点位于碱基1812和1913之间,琼脂糖凝胶电泳发现PCR扩增的突变Ⅱ组内含子RNP基因序列分子量大小和预期值(350 bp)相一致,用NheⅠ

  18. Creation of fragrant rice by targeted knockout of the OsBADH2 gene using TALEN technology.

    Science.gov (United States)

    Shan, Qiwei; Zhang, Yi; Chen, Kunling; Zhang, Kang; Gao, Caixia

    2015-08-01

    Fragrant rice is favoured worldwide because of its agreeable scent. The presence of a defective badh2 allele encoding betaine aldehyde dehydrogenase (BADH2) results in the synthesis of 2-acetyl-1-pyrroline (2AP), which is a major fragrance compound. Here, transcription activator-like effector nucleases (TALENs) were engineered to target and disrupt the OsBADH2 gene. Six heterozygous mutants (30%) were recovered from 20 transgenic hygromycin-resistant lines. Sanger sequencing confirmed that these lines had various indel mutations at the TALEN target site. All six transmitted the BADH2 mutations to the T1 generation; and four T1 mutant lines tested also efficiently transmitted the mutations to the T2 generation. Mutant plants carrying only the desired DNA sequence change but not the TALEN transgene were obtained by segregation in the T1 and T2 generations. The 2AP content of rice grains of the T1 lines with homozygous mutations increased from 0 to 0.35-0.75 mg/kg, which was similar to the content of a positive control variety harbouring the badh2-E7 mutation. We also simultaneously introduced three different pairs of TALENs targeting three separate rice genes into rice cells by bombardment and obtained lines with mutations in one, two and all three genes. These results indicate that targeted mutagenesis using TALENs is a useful approach to creating important agronomic traits.

  19. LEU2基因敲除对工业啤酒酵母高级醇生成量的影响%Effect of LEU2 gene knockout on higher alcohols production in industrial Saccharomyces cerevisiae

    Institute of Scientific and Technical Information of China (English)

    佐一含; 朱旭东; 陈叶福; 吕鸿雁; 肖冬光

    2011-01-01

    Effect of β-isopropylmalate dehydrogenase gene (LEU2) on production of higher alcohols, especially isoamyl alcohol, in industrial brewing yeast was studied with the method of gene knockout. The recombinant cassette Po3-KanMX-Po4 with LEU2 gene homology region at both ends and with KanMX gene in the middle was amplified by PCR. The obtained Po3-KanMX-Po4 fragment was transformed into Saccharomyces cerevisiae using lithium acetate method. The mutant with LEU2 knocked out was selected out by the resistance to geneticin (G418) and further confirmed by PCR. Fermentation performance and production of higher alcohols by the mutant was compared with parental strain S6 in different fermentation medium. Mutant S6-1 with at least one copy of LEU2 gene knockout was obtained. The fermentation test results showed that the production of higher alcohols from this mutant was reduced by 9.97%, of which the content of isoamyl alcohol was reduced by 11 .82% when using a low branched-chain amino acids containing medium, while alcohol content, fermentation rate and other fermentation performance did not change significantly. Production of higher alcohols, especially isoamyl alcohol in the industrial S. cerevisiae S6 with LEU2 gene knockout was decreased when the branched-chain amino acids in the medium were insufficient.%通过敲除啤酒酵母中β-丙基苹果酸脱氢酶基因(LEU2),研究该基因对工业啤酒酵母高级醇特别是异戊醇生成量的影响.通过醋酸锂一步转化法,将一段两端具有LEU2摹因序列同源区,中间为遗传霉素(G418)抗性基因的DNA片段转入酵母细胞中,与LEU2基因的ORF(open reading flames)进行同源重组,利用遗传霉素抗性进行筛选.将突变株与出发菌株进行发酵实验,测定其发酵性能和高级醇的生成量.筛选获得了LEU2摹因突变的工业啤酒酵母.在支链氨基酸含量较低的培养基中进行发酵测定,突变株发酵液中高级醇含量比出发菌株降低了9.97%,

  20. Transgenic expression of human INS gene in Ins1/Ins2 double knockout mice leads to insulin underproduction and diabetes in some male mice.

    Science.gov (United States)

    Karaca, Melis; Durel, Béatrice; Languille, Laëtitia; Lamotte, Luciane; Tourrel-Cuzin, Cécile; Leroux, Loïc; Abou Sleymane, Gretta; Saint-Just, Susan; Bucchini, Danielle; Ktorza, Alain; Joshi, Rajiv L

    2007-01-01

    We have generated transgenic mouse lines expressing exclusively a human INS transgene on an Ins1/Ins2 double knockout (mIKO) background. The transgene expression was driven by either a 4000 bp or a 353 bp promoter. These transgenic lines, designated mIKO:INS4000 and mIKO:INS353, were viable and fertile. Determination of the amounts of insulin transcripts and total pancreatic insulin content revealed relative insulin underproduction in both lines, from birth to adulthood. Total pancreatic insulin stores in mIKO:INS4000 and mIKO:INS353 mice represented only about 50% and 27%, respectively, as compared to wild-type mice. Morphometric analysis of pancreas did not show any compensatory beta-cell hyperplasia. The majority of animals in both lines remained normoglycemic throughout their lives. Nevertheless, glucose tolerance tests revealed glucose intolerance in nearly half of mIKO:INS4000 male mice, likely due to impaired insulin secretion detected in those animals. In addition, a small fraction (2-4%) of male mice in both lines spontaneously developed diabetes with very distinct pathophysiological features. Diabetes was never seen in female animals. The diabetes developed by mIKO:INS353 mice was rapidly lethal, accompanied by a dramatic depletion of pancreatic insulin stores whereas the mIKO:INS4000 diabetic animals could live for several months. This suggests a possible link between the structure of the human INS gene promoter and the type of diabetes developed in these lines.

  1. Construction of a host range-expanded hybrid baculovirus of BmNPV and AcNPV,and knockout of cysteinase gene for more efficient expression

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    AcNPV(Autographa californica nuclear polyhedrosis virus)and BmNPV(Bombyx mori nuclear polyhedrosis virus)are two principal insect-baculovirus expression systems,each having different characteristics.AcNPV has a wider host range and can infect a series of cell lines thus making it suitable for cell suspension culture expression,but the small size of the host insect,A.californica,makes AcNPV less suitable for large scale protein synthesis.In contrast,BmNPV can only infect the silkworm,Bornbyx rnori,which is well-known for its easy rearing and large size.These characteristics make the BmNPV system especially suitable for large-scale industrial expression.To utilize the advantages of both AcNPV and BmNPV,we tried to expand their host range through homologous recombination and successfully constructed a hybrid baculovirus of AcNPV and BmNPV,designated as HyNPV.The hybrid baculovirus can infect the hosts of both AcNPV and BmNPV.Taking the human basic fibroblast growth factor(Bfgf)gene as an application example,we constructed a recombinant,HyNPV-Bfgf.This construct is able to express the Bfgf protein both in silkworm larvae and in common-use cell lines,sf21,sf9 and High-five.Moreover,to reduce the loss of recombinant protein due to degradation by proteases that are simultaneously expressed by the baculovirus,we knocked out the cysteinase gene coding for one of the most important baculovirus proteases.This knockout mutation improves the production efficiency of the Bfgf recombinant protein.

  2. 轮枝镰孢菌FvST12基因敲除载体的构建及功能分析%Gene Knockout Vector Construction and Function Assay of FvST12 in Fusarium verticillioides

    Institute of Scientific and Technical Information of China (English)

    张岳平; 瞿华香

    2011-01-01

    [目的]鉴定并分析轮枝镰孢菌中 STE12 类转录因子的基因功能.[方法]以尖孢镰孢菌转录因子Fost12蛋白为靶序列,在轮枝镰孢菌基因组数据库中进行BlastP搜索,发现一个与Fost12蛋白同源性高达98%的基因,命名为FvST12.基于Double-Joint PCR技术,构建该基因的敲除载体,通过真菌原生质体转化及筛选获得基因敲除突变体,并对突变体的表型及致病性进行系统分析,以明确该基因的功能.[结果l突变体在生长速率、菌落形态,产孢量以及高渗和氧化等逆境胁迫反应上与野生型无显著差异;致病性分析表明,突变体致病力明显下降.[结论]轮枝镰孢菌FvST12对致病性起重要调控作用,但不参与营养生长、产孢和高渗和氧化胁迫等逆境反应.%[Objective]The objective of this study is to identify and analyze the STE12 homolog transcription factor gene in Fusarium verticillioides.[Method]The F.oxysporum Fostl2 transcription factor was used as a target sequence to search its homolog by BlastP in F.verticillioides genome sequence.FVEG_05267.3, a predicted gene in F.verticillioides, was identified and it showed 98% similarity to Fostl2.It was called FvST12 in this study.Based on the Double-Joint PCR, the knockout vector was constructed and null knockout mutants were generated through fungal protoplast transformation.The gene knockout mutants were confirmed by PCR and Southern blot.Furthermore, the function of the gene in F.vertieillioides was systematically characterized [Result]Compared with the wild type, Fvstl2 mutant has normal growth rate, condiation, colony morphology, and stress responses (osmotic and oxidative stress) tested in this study.However, the mutant reduced the virulence on maize ear and stalk.[Conclusion]The transcription factor FvST12 is an important virulence factor but it isn't involved in the vegetative growth, conidiation, osmotic and oxidative stress responses in F.verticillioides.

  3. Gene knockout demonstrates that vip3A contributes to the pathogenesis of Bacillus thuringiensis toward Agrotis ipsilon and Spodoptera exigua.

    Science.gov (United States)

    Donovan, W P; Donovan, J C; Engleman, J T

    2001-07-01

    Vip3A is an 89-kDa protein secreted by Bacillus thuringiensis during vegetative growth. To determine the importance of Vip3A for the insect pathogenicity of B. thuringiensis the vip3A gene was deleted from strain HD1, yielding strain HD1Deltavip3A. Compared with HD1, strain HD1Deltavip3A was one-fourth as toxic to Agrotis ipsilon larvae and less than one-tenth as toxic to Spodoptera exigua larvae. When streptomycin was included in the S. exigua diet the toxicity of HD1Deltavip3A was approximately half that of HD1. Addition of HD1 spores increased the toxicity of purified Cry1 protein more than 600-fold against S. exigua, whereas addition of HD1Deltavip3A spores increased toxicity of Cry1 protein approximately 10-fold. These results demonstrate that an important component of B. thuringiensis insecticidal activity against S. exigua is the synthesis of Vip3A protein by B. thuringiensis cells after ingestion of spores and crystal proteins by insect larvae.

  4. TALEN Gene Knockouts Reveal No Requirement for the Conserved Human Shelterin Protein Rap1 in Telomere Protection and Length Regulation

    Directory of Open Access Journals (Sweden)

    Shaheen Kabir

    2014-11-01

    Full Text Available The conserved protein Rap1 functions at telomeres in fungi, protozoa, and vertebrates. Like yeast Rap1, human Rap1 has been implicated in telomere length regulation and repression of nonhomologous end-joining (NHEJ at telomeres. However, mouse telomeres lacking Rap1 do not succumb to NHEJ. To determine the functions of human Rap1, we generated several transcription activator-like effector nuclease (TALEN-mediated human cell lines lacking Rap1. Loss of Rap1 did not affect the other components of shelterin, the modification of telomeric histones, the subnuclear position of telomeres, or the 3′ telomeric overhang. Telomeres lacking Rap1 did not show a DNA damage response, NHEJ, or consistent changes in their length, indicating that Rap1 does not have an important function in protection or length regulation of human telomeres. As human Rap1, like its mouse and unicellular orthologs, affects gene expression, we propose that the conservation of Rap1 reflects its role in transcriptional regulation rather than a function at telomeres.

  5. Knockout Reaction Mechanism for 6He+%Knockout Reaction Mechanism for 6He+

    Institute of Scientific and Technical Information of China (English)

    吕林辉; 叶沿林; 曹中鑫; 肖军; 江栋兴; 郑涛; 华辉; 李智焕; 葛俞成; 李湘庆; 楼建玲; 李阔昂; 李奇特; 乔锐; 游海波; 陈瑞九

    2012-01-01

    A knockout reaction experiment was carried out by using the 6He beam at 82.5 MeV/nucleon impinging on CH2 and C targets. The a core fragments at forward angles were detected in coincidence with the recoiled protons at larger angles. From this exclusive measure- ment the valence nucleon knockout mechanism and the core knockout mechanism are separated. This study provides a basis for the exclusive spectroscopic investigation of the exotic nuclei.

  6. Acinar cell-specific knockout of the PTHrP gene decreases the proinflammatory and profibrotic responses in pancreatitis

    Science.gov (United States)

    Bhatia, Vandanajay; Rastellini, Cristiana; Han, Song; Aronson, Judith F.; Greeley, George H.

    2014-01-01

    Pancreatitis is a necroinflammatory disease with acute and chronic manifestations. Accumulated damage incurred during repeated bouts of acute pancreatitis (AP) can lead to chronic pancreatitis (CP). Pancreatic parathyroid hormone-related protein (PTHrP) levels are elevated in a mouse model of cerulein-induced AP. Here, we show elevated PTHrP levels in mouse models of pancreatitis induced by chronic cerulein administration and pancreatic duct ligation. Because acinar cells play a major role in the pathophysiology of pancreatitis, mice with acinar cell-specific targeted disruption of the Pthrp gene (PTHrPΔacinar) were generated to assess the role of acinar cell-secreted PTHrP in pancreatitis. These mice were generated using Cre-LoxP technology and the acinar cell-specific elastase promoter. PTHrPΔacinar exerted protective effects in cerulein and pancreatic duct ligation models, evident as decreased edema, histological damage, amylase secretion, pancreatic stellate cell (PSC) activation, and extracellular matrix deposition. Treating acinar cells in vitro with cerulein increased IL-6 expression and NF-κB activity; these effects were attenuated in PTHrPΔacinar cells, as were the cerulein- and carbachol-induced elevations in amylase secretion. The cerulein-induced upregulation of procollagen I expression was lost in PSCs from PTHrPΔacinar mice. PTHrP immunostaining was elevated in human CP sections. The cerulein-induced upregulation of IL-6 and ICAM-1 (human acinar cells) and procollagen I (human PSCs) was suppressed by pretreatment with the PTH1R antagonist, PTHrP (7–34). These findings establish PTHrP as a novel mediator of inflammation and fibrosis associated with CP. Acinar cell-secreted PTHrP modulates acinar cell function via its effects on proinflammatory cytokine release and functions via a paracrine pathway to activate PSCs. PMID:25035110

  7. New Understandings on Folliculogenesis/Oogenesis Regulation in Mouse as Revealed by Conditional Knockout

    Institute of Scientific and Technical Information of China (English)

    Meng-Wen Hu; Zhen-Bo Wang; Heide Schatten; Qing-Yuan Sun

    2012-01-01

    In comparison to conventional knockout technology and in vitro research methods,conditional gene knockout has remarkable advantages.In the past decade,especially during the past five years,conditional knockout approaches have been used to study the regulation of folliculogenesis,follicle growth,oocyte maturation and other major reproductive events.In this review,we summarize the recent findings about folliculogenesis/oogenesis regulation,including the functions of four signaling cascades or glycoprotein domains that have been extensively studied by conditional gene deletion.Several other still fragmented areas of related work are introduced which are awaiting clarification.We have also discussed the future potential of this technology in clarifying gene functions in reproductive biology.

  8. Alterations in the expression of a neurodevelopmental gene exert long-lasting effects on cognitive-emotional phenotypes and functional brain networks: translational evidence from the stress-resilient Ahi1 knockout mouse.

    Science.gov (United States)

    Lotan, A; Lifschytz, T; Mernick, B; Lory, O; Levi, E; Ben-Shimol, E; Goelman, G; Lerer, B

    2017-06-01

    Many psychiatric disorders are highly heritable and may represent the clinical outcome of early aberrations in the formation of neural networks. The placement of brain connectivity as an 'intermediate phenotype' renders it an attractive target for exploring its interaction with genomics and behavior. Given the complexity of genetic make up and phenotypic heterogeneity in humans, translational studies are indicated. Recently, we demonstrated that a mouse model with heterozygous knockout of the key neurodevelopmental gene Ahi1 displays a consistent stress-resilient phenotype. Extending these data, the current research describes our multi-faceted effort to link early variations in Ahi1 expression with long-term consequences for functional brain networks and cognitive-emotional phenotypes. By combining behavioral paradigms with graph-based analysis of whole-brain functional networks, and then cross-validating the data with robust neuroinformatic data sets, our research suggests that physiological variation in gene expression during neurodevelopment is eventually translated into a continuum of global network metrics that serve as intermediate phenotypes. Within this framework, we suggest that organization of functional brain networks may result, in part, from an adaptive trade-off between efficiency and resilience, ultimately culminating in a phenotypic diversity that encompasses dimensions such as emotional regulation and cognitive function.

  9. Pharmacological functions of multidrug transporters: studies employing combination transporter knockout mice

    NARCIS (Netherlands)

    Lagas, J.S.

    2009-01-01

    ATP-binding cassette (ABC) multidrug transporters are drug efflux pumps located in the plasma membrane that utilize the energy of ATP hydrolysis to extrude a wide spectrum of endogenous and exogenous compounds from cells, including numerous (anticancer) drugs and/or their metabolites. The studies de

  10. Lethality of mice bearing a knockout of the Ngly1-gene is partially rescued by the additional deletion of the Engase gene.

    Directory of Open Access Journals (Sweden)

    Haruhiko Fujihira

    2017-04-01

    Full Text Available The cytoplasmic peptide:N-glycanase (Ngly1 in mammals is a de-N-glycosylating enzyme that is highly conserved among eukaryotes. It was recently reported that subjects harboring mutations in the NGLY1 gene exhibited severe systemic symptoms (NGLY1-deficiency. While the enzyme obviously has a critical role in mammals, its precise function remains unclear. In this study, we analyzed Ngly1-deficient mice and found that they are embryonic lethal in C57BL/6 background. Surprisingly, the additional deletion of the gene encoding endo-β-N-acetylglucosaminidase (Engase, which is another de-N-glycosylating enzyme but leaves a single GlcNAc at glycosylated Asn residues, resulted in the partial rescue of the lethality of the Ngly1-deficient mice. Additionally, we also found that a change in the genetic background of C57BL/6 mice, produced by crossing the mice with an outbred mouse strain (ICR could partially rescue the embryonic lethality of Ngly1-deficient mice. Viable Ngly1-deficient mice in a C57BL/6 and ICR mixed background, however, showed a very severe phenotype reminiscent of the symptoms of NGLY1-deficiency subjects. Again, many of those defects were strongly suppressed by the additional deletion of Engase in the C57BL/6 and ICR mixed background. The defects observed in Ngly1/Engase-deficient mice (C57BL/6 background and Ngly1-deficient mice (C57BL/6 and ICR mixed background closely resembled some of the symptoms of patients with an NGLY1-deficiency. These observations strongly suggest that the Ngly1- or Ngly1/Engase-deficient mice could serve as a valuable animal model for studies related to the pathogenesis of the NGLY1-deficiency, and that cytoplasmic ENGase represents one of the potential therapeutic targets for this genetic disorder.

  11. Generation of gene knockouts and mutant models in the laboratory rat by ENU-driven target-selected mutagenesis

    NARCIS (Netherlands)

    Smits, Bart M G; Mudde, Josine B; van de Belt, Jose; Verheul, Mark; Olivier, Jocelien; Homberg, Judith; Guryev, Victor; Cools, Alexander R; Ellenbroek, Bart A; Plasterk, Ronald H A; Cuppen, Edwin

    2006-01-01

    OBJECTIVE: The rat is one of the most important model organisms for biomedical and pharmacological research. However, the generation of novel models for studying specific aspects of human diseases largely depends on selection for specific traits using existing rat strains, thereby solely depending o

  12. Generation of gene knockouts and mutant models in the laboratory rat by ENU-driven target-selected mutagenesis.

    NARCIS (Netherlands)

    Smits, B.M.; Mudde, J.B.; Belt, J. van de; Verheul, M.; Olivier, J.; Homberg, J.R.; Guryev, V.; Cools, A.R.; Ellenbroek, B.A.; Plasterk, R.H.; Cuppen, E.

    2006-01-01

    OBJECTIVE: The rat is one of the most important model organisms for biomedical and pharmacological research. However, the generation of novel models for studying specific aspects of human diseases largely depends on selection for specific traits using existing rat strains, thereby solely depending o

  13. Observation of tail suspension test in Fmr1 gene knockout mice%Fmr1基因敲除小鼠悬尾实验的观察

    Institute of Scientific and Technical Information of China (English)

    胡丽婵; 黄海樱; 郭艺; 孙祺章; 余国汉; 黄月玲; 戴丽军; 党亚梅; 黄雄; 陈盛强

    2016-01-01

    Objective To observe tail suspension test in Fmr1 gene knockout mice and to explore whether there are differences in mobility of KO and WT mice. Methods 1 80 test mice were divided into two groups:① KO group (4,6,8 weeks old,each age group of mice is 30,male and female in half,a total of 90)② WT group (4,6,8 weeks old,each group of mice is 30,male and female on half,a total of 90).Through forced swimming test and tail suspension test to observe gender, age effect on immobility time. Results With the same age of the same sex,the KO mice’s immobility time was longer than WT mice’s.P <0.05.With the same age,the male mice’s immobility time was shorter than female mice’s.With the age in-crease,the immobility time of KO mice was longer than WT mice.P <0.05. Conclusion Fmr1 gene knockout mice have anxiety and depressive behavior.%目的:对不同周龄的 KO 小鼠与 WT 小鼠进行悬尾实验进行观察,探讨 KO 小鼠与 WT 小鼠的行为差别。方法采用健康的试验动物180只分两组:①KO 组(4、6、8周龄,各周龄30只,雌雄各半,共90只)②WT 组(4、6、8周龄,各周龄30只,雌雄各半,共90只);通过悬尾实验观察性别,年龄对不动时间的影响。结果同龄 KO 雌性小鼠比雄性小鼠的静止时间差别不大;随着年龄增大,静止时间增长。同龄同性别的 KO 鼠比 WT 鼠的不动时间长。P <0.05;同龄雄性小鼠比雌性小鼠的不动时间短;随年龄增长各种系小鼠不动时间增长,KO 鼠的不动时间比 WT 鼠长,P <0.05。结论 KO 小鼠存在抑郁行为表型。

  14. Altered gene expression and functional activity of opioid receptors in the cerebellum of CB1 cannabinoid receptor knockout mice after acute treatments with cannabinoids.

    Science.gov (United States)

    Páldyová, Estera; Bereczki, E; Sántha, M; Wenger, T; Borsodi, Anna; Benyhe, S

    2007-01-01

    Numerous studies have shown functional links between the cannabinoid and opioid systems. The goal of this study was to evaluate whether acute treatments by endogenous cannabinoid agonist, selective CB1 or CB2 receptor antagonists modulate the expression of mu- (MOR) and delta- (DOR) opioid receptor mRNA levels and functional activity in the cerebellum of transgenic mice deficient in the CB1 type of cannabis receptors. We examined the effect of noladin ether (endogenous cannabinoid agonist) pretreatment on MOR and DOR mRNA expression by using reverse transcription and real-time polimerase chain reaction (PCR) and the ability of subsequent application of the opioid agonists to activate G-proteins, as measured by [35S]GTPgammaS binding, in wild-type (CB1+/+) and CB1 cannabinoid receptor deficient (CB1-/-, 'knockout', K.O.) mice. The acute administration of noladin ether markedly reduced MOR-mediated G-protein activation and caused a significant increase in the level of MOR mRNAs in the cerebella of wildtype, but not in the CB1-/- mice. No significant differences were observed in DOR functional activity and mRNA expression in wild-type animals. In CB1-/- mice the expression of DOR mRNA increased after noladin ether treatment, but no changes were found in DOR functional activity. In addition, Rimonabant (selective central cannabinoid CB1 receptor antagonist) and SR144528 (selective peripheral cannabinoid CB2 receptor antagonist) caused significant potentiation in MOR functional activity in the wild-type animals, whereas DOR mediated G-protein activation was increased in the CB1-/- mice. In contrast, Rimonabant and SR144528 decreased the MOR and DOR mRNA expressions in both CB1+/+ and CB1-/- mice. Taken together, these results indicate that acute treatment with cannabinoids causes alterations in MOR and DOR mRNA expression and functional activity in the cerebella of wild-type and CB1 knockout mice indicating indirect interactions between these two signaling systems.

  15. Fmr1基因敲除雄性小鼠生长指标的变化%Observation on the results of body weight and length of male mince with Fmr1 gene knockout.

    Institute of Scientific and Technical Information of China (English)

    杨乙; 刘国彬; 刘绪红; 林波; 黄月玲; 沈岩松; 张维雯; 孙卫文; 李敏雄; 陈盛强

    2011-01-01

    目的 对出生后0~56d的清洁级FVB小鼠和Fmr1基因敲除雄性小鼠的体重和体长指标进行分析比较,同时比较出生后28d的睾丸大小变化.方法 挑选10周龄FVB小鼠和Fmr1基因敲除小鼠各20只(雌、雄各半),采取1:I同居,全同胞兄妹近交繁殖,测定雄性子代生长发育指标,进行统计分析.结果 出生后0~56d清洁级Fmr1基因敲除雄性小鼠体重与体长的增长与FVB小鼠差异无统计学意义(t=0.93,t=1.24,P>0.05),但出生后28d的FVB小鼠和Fmr1基因敲除雄性小鼠睾丸大小差别有统计学意义(t=4.12,P<0.05).结论 Fmr1基因敲除不影响雄性小鼠正常的体重和体长的发育,但出生后28d的Fmr1基因敲除小鼠有巨睾征.%Objective To characterize the growth performance of FVB mice and Fmrl gene knockout mice. Methods There 20 seed FVB micedO males and 10 females,aged 10 weeks)were chosen and monogamously mated. The parameters of growth performance were analyzed. And these analysis also conducted on male Fmrl gene knockout mice. Results There no significant statistical differences in average weight and length of the newboms FVB and Fmrl gene knockout mice within 56 days after borth were observed. While significant differences were observed in size of testes of FVB mice and Fmrl gene knockout mice 28 days after birth. Conclusion Fmrl gene knockout does not affect the growth and weight of the mice but the mice may have giant testes.

  16. 肠出血性大肠杆菌O157∶H7Ⅲ型分泌系统效应蛋白NleF基因敲除菌株的构建及其生物学功能初探%Construction and preliminary study of biological functions of O157∶H7 typeⅢsecre-tion system effector NleF gene knockout mutant

    Institute of Scientific and Technical Information of China (English)

    徐婷婷; 宋婷; 周围; 戴红梅; 岳俊杰; 梁龙

    2015-01-01

    目的:构建肠出血性大肠杆菌(enterohemorrhagic Escherichia coli,EHEC)O157∶H7 T3SS效应蛋白NleF敲除菌株和回复菌株,研究其对细菌生长和细胞死亡的影响。方法利用λ-Red同源重组的方法构建nleF基因敲除菌株ΔnleF;将pET-24a(+)-NleF重组质粒导入敲除菌感受态细胞中构建回复菌株ΔnleF/NleF。将野生株、敲除株和回复株分别用LB和DMEM(10%FBS)培养,每隔1 h测定D600,绘制生长曲线;分别用3种菌株感染HeLa细胞,用细胞毒性试剂盒检测上清中乳酸脱氢酶( LDH)的释放量,计算细胞毒性。结果成功构建NleF敲除菌株ΔnleF和回复菌株ΔnleF/NleF;野生株、敲除株和回复株三者的生长速率无明显差异;与野生株相比,ΔnleF感染HeLa细胞后,细胞毒性增加,ΔnleF/NleF感染后HeLa细胞毒性与野生株相当。结论 EHEC O157∶H7 T3SS 效应蛋白NleF对细菌的生长无明显影响,但可能抑制由细菌感染引起的宿主细胞死亡。%Objective To construct Escherichia coli O157∶H7 T3SS effector NleF gene knockout mutant and its com-plementary strain, and probe its effects on bacterial growth and cell death .Methods T3SS Effector NleF gene knockout mutant ΔnleF was constructed with λ-Red homologous recombination .Complementary strain ΔnleF/NleF was constructed by transferring pET-24a(+)-NleF into ΔnleF competent cells.Wild type,ΔnleF and ΔnleF/NleF were cultured in LB and DMEM(10%FBS) respectively,D600 was measured every hour , and the growth curve was drawn .HeLa cells were infected with three kinds of strains , the supernatant of LDH release was detected with cytotoxicity detection kit ,and the cytotoxicity was calculated .Results ΔnleF and ΔnleF/NleF were constructed .The growth rates of wild type , ΔnleF and ΔnleF/NleF was not significantly different .Wild type O157 infection induced cell death .Cytotoxicity was increased as much in ΔnleF in

  17. Sarcocystis neurona infection in gamma interferon gene knockout (KO) mice: comparative infectivity of sporocysts in two strains of KO mice, effect of trypsin digestion on merozoite viability, and infectivity of bradyzoites to KO mice and cell culture.

    Science.gov (United States)

    Dubey, J P; Sundar, N; Kwok, O C H; Saville, W J A

    2013-09-01

    The protozoan Sarcocystis neurona is the primary cause of Equine Protozoal Myeloencephalitis (EPM). EPM or EPM-like illness has been reported in horses, sea otters, and several other mammals. The gamma interferon gene knockout (KO) mouse is often used as a model to study biology and discovery of new therapies against S. neurona because it is difficult to induce clinical EPM in other hosts, including horses. In the present study, infectivity of three life cycle stages (merozoites, bradyzoites, sporozoites) to KO mice and cell culture was studied. Two strains of KO mice (C57-black, and BALB/c-derived, referred here as black or white) were inoculated orally graded doses of S. neurona sporocysts; 12 sporocysts were infective to both strains of mice and all infected mice died or became ill within 70 days post-inoculation. Although there was no difference in infectivity of sporocysts to the two strains of KO mice, the disease was more severe in black mice. S. neurona bradyzoites were not infectious to KO mice and cell culture. S. neurona merozoites survived 120 min incubation in 0.25% trypsin, indicating that trypsin digestion can be used to recover S. neurona from tissues of acutely infected animals. Published by Elsevier B.V.

  18. Construction of H22 GP73 knockout gene stable strain using CRISPR/Cas9 gene editing system and identification of functions%利用CRISPR/Cas9系统构建H22细胞GP73基因敲除稳定株及功能鉴定

    Institute of Scientific and Technical Information of China (English)

    陈健康; 魏从文; 梁慧; 王贝晗; 钟辉; 杨晓莉

    2016-01-01

    GP73 knockout gene stable strain after transfection.The transfer and reproduction slowed down .Conclusion H22 GP73 gene knockout stable strain can be successfully built using CRISPR/Cas9 gene editing system ,thus facilitating studies on the function of GP 73 in hepatocarcinogenesis .

  19. Construction and functional studies of uropathogenic E.coli strains with ompT gene knockout%尿路致病性大肠埃希菌外膜蛋白T敲除株的构建及功能评价

    Institute of Scientific and Technical Information of China (English)

    赵铁; 方幸幸; 刘晓露; 彭亮; 龙敏; 张文炳; 罗军; 曹虹

    2012-01-01

    目的 探索外膜蛋白T(OmpT)基因在尿路致病性大肠埃希菌(UPEC)CFT073致尿路感染中的作用.方法 利用RED重组技术构建UPEC CFT073 0mpT基因缺失株(命名为COTD),并建立小鼠急性尿路感染模型,体内外实验比较野生株与敲除株之间在膀胱组织的定植能力.结果 PCR分析及测序鉴定证实ompT基因缺失株构建成功;体外实验结果显示野生株粘附率为(8.3±1.9)%,敲除株粘附率为(6 7±2.2)%,敲除株粘附率明显低于野生株(P<0.05).体内实验膀胱组织内,野生株定植细菌数为(7±2)x 105 cfu,敲除株定植细菌数为(17±8)x104 cfu,ompT敲除株定植于膀胱组织的能力明显降低(P<0.05).结论 证实OmpT作为毒力因子参与细菌定植膀胱组织,在UPEC致尿路感染的过程中发挥重要作用.%Objective To explore the role of ompT gene in uropathogenic E. coli (UPEC) CFT073 strain in urinary tract infection (UTI). Methods An ompT deletion mutant (COTD) was generated by A Red recombineering in the UPEC CFT073 strain, which was characterized by PCR and sequencing. C57B/L6 mouse models of acute UTI with the mutant and wild-type strains were established to compare the colonization abilities of the two strains in the bladder. The adhesion of CFT073 mutant to human unthelial 5637 cells was also investigated in vitro. Results PCR and DNA sequencing confirmed the loss of ompT gene in the mutant COTD. The in vitro adhesion rate of the mutant strain COTD to 5637 cells was (6.7±2.2)%, significantly lower than that of (8.3 + 1.9)% of the wild-type strain (P<0.05). In the murine models of acute UTI, the mutant strain showed a mean colonization number of about (17±8)×104 cfu, which was significantly lower than that of (7±2)×105 cfu of the wide-type CFT073 strain (P<0.05). Conclusion OmpT gene can be involved in the colonization of UPEC in the bladder tissue and plays an important role in the pathogenesis of UPEC-induced UTI.

  20. CRISPR/Cas9 Promotes Functional Study of Testis Specific X-Linked Gene In Vivo.

    Directory of Open Access Journals (Sweden)

    Minyan Li

    Full Text Available Mammalian spermatogenesis is a highly regulated multistage process of sperm generation. It is hard to uncover the real function of a testis specific gene in vitro since the in vitro model is not yet mature. With the development of the CRISPR/Cas9 (Clustered Regularly Interspaced Short Palindromic Repeats/CRISPR-associated 9 system, we can now rapidly generate knockout mouse models of testis specific genes to study the process of spermatogenesis in vivo. SYCP3-like X-linked 2 (SLX2 is a germ cell specific component, which contains a Cor1 domain and belongs to the XLR (X-linked, lymphocyte regulated family. Previous studies suggested that SLX2 might play an important role in mouse spermatogenesis based on its subcellular localization and interacting proteins. However, the function of SLX2 in vivo is still elusive. Here, to investigate the functions of SLX2 in spermatogenesis, we disrupted the Slx2 gene by using the CRISPR/Cas9 system. Since Slx2 is a testis specific X-linked gene, we obtained knockout male mice in the first generation and accelerated the study process. Compared with wild-type mice, Slx2 knockout mice have normal testis and epididymis. Histological observation of testes sections showed that Slx2 knockout affected none of the three main stages of spermatogenesis: mitosis, meiosis and spermiogenesis. In addition, we further confirmed that disruption of Slx2 did not affect the number of spermatogonial stem cells, meiosis progression or XY body formation by immunofluorescence analysis. As spermatogenesis was normal in Slx2 knockout mice, these mice were fertile. Taken together, we showed that Slx2 itself is not an essential gene for mouse spermatogenesis and CRISPR/Cas9 technique could speed up the functional study of testis specific X-linked gene in vivo.

  1. Effects of NV gene knock-out recombinant viral hemorrhagic septicemia virus (VHSV) on Mx gene expression in Epithelioma papulosum cyprini (EPC) cells and olive flounder (Paralichthys olivaceus).

    Science.gov (United States)

    Kim, Min Sun; Kim, Ki Hong

    2012-03-01

    To determine whether the NV gene of viral hemorrhagic septicemia virus (VHSV) is related to the type I interferon response of hosts, expression of Mx gene in Epithelioma papulosum cyprini (EPC) cells and in olive flounder (Paralichthys olivaceus) in response to infection with either wild-type VHSV or recombinant VHSVs (rVHSV-ΔNV-EGFP and rVHSV-wild) was investigated. A reporter vector was constructed for measuring Mx gene expression using olive flounder Mx promoter, in which the reporter Metridia luciferase was designed to be excreted to culture medium to facilitate measurement. The highest increase of luciferase activity was detected from supernatant of cells infected with rVHSV-ΔNV-EGFP. In contrast cells infected with wild-type VHSV showed a slight increase of the luciferase activity. Interestingly, cells infected with rVHSV-wild that has artificially changed nucleotides just before and after the NV gene ORF, also showed highly increased luciferase activity, but the increased amplitude was lower than that by rVHSV-ΔNV-EGFP. These results strongly suggest that the NV protein of VHSV plays an important role in suppressing interferon response in host cells, which provides a condition for the viruses to efficiently proliferate in host cells. In an in vivo experiment, the Mx gene expression in olive flounder challenged with the rVHSV-ΔNV-EGFP was clearly higher than fish challenged with rVHSV-wild or wild-type VHSV, suggesting that lacking of the NV gene in the genome of rVHSV-ΔNV-EGFP brought to strong interferon response that subsequently inhibit viral replication in fish.

  2. Knockout of crtB or crtI gene blocks the carotenoid biosynthetic pathway in Deinococcus radiodurans R1 and influences its resistance to oxidative DNA-damaging agents due to change of free radicals scavenging ability.

    Science.gov (United States)

    Zhang, Lei; Yang, Qiao; Luo, Xuesong; Fang, Chengxiang; Zhang, Qiuju; Tang, Yali

    2007-10-01

    Deinococcus radiodurans R1, a red-pigmented strain of the extremely radioresistant genus Deinococcus, contains a major carotenoid namely deinoxanthin. The high resistance of this organism against the lethal actions of DNA-damaging agents including ionizing radiation and ultraviolet light (UV) has been widely reported. However, the possible antioxidant role of carotenoids in this strain has not been completely elucidated. In this study, we constructed two colorless mutants by knockout of crtB and crtI genes, respectively. Comparative analysis of the two colorless mutants and the wild type showed that the two colorless mutants were more sensitive to ionizing radiation, UV, and hydrogen peroxide, but not to mitomycin-C (MMC). With electron spin resonance (ESR) and spin trapping techniques, we observed that hydroxyl radical signals occurred in the suspensions of UV irradiated Deinococcus radiodurans cells and the intensity of signals was influenced by carotenoids levels. We further showed that the carotenoid extract from the wild type could obviously scavenge superoxide anions generated by the irradiated riboflavin/EDTA system. These results suggest that carotenoids in D. radiodurans R1 function as free radical scavengers to protect this organism against the deleterious effects of oxidative DNA-damaging agents.

  3. Knockout reactions: experimental aspects

    Energy Technology Data Exchange (ETDEWEB)

    Cortina Gil, D. [Santiago de Compostela Univ. (Spain)

    2007-07-01

    The availability of radioactive beams has given rise to intense activity in the field of direct reactions. The removal of one(two)-nucleon (referred to as nucleon knockout in this text) from a fast exotic projectile has been extensively investigated. This lecture provides a general overview of the experimental results achieved using this technique. The sensitivity of the method to different experimental aspects is illustrated with a few examples. Special attention is given to the application of nucleon-knockout reactions as a general purpose spectroscopic tool. (author)

  4. 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.

  5. 11β-hydroxysteroid dehydrogenase type 1 gene knockout attenuates atherosclerosis and in vivo foam cell formation in hyperlipidemic apoE⁻/⁻ mice.

    Directory of Open Access Journals (Sweden)

    Ricardo A García

    Full Text Available BACKGROUND: Chronic glucocorticoid excess has been linked to increased atherosclerosis and general cardiovascular risk in humans. The enzyme 11β-hydroxysteroid dehydrogenase type 1 (11βHSD1 increases active glucocorticoid levels within tissues by catalyzing the conversion of cortisone to cortisol. Pharmacological inhibition of 11βHSD1 has been shown to reduce atherosclerosis in murine models. However, the cellular and molecular details for this effect have not been elucidated. METHODOLOGY/PRINCIPAL FINDINGS: To examine the role of 11βHSD1 in atherogenesis, 11βHSD1 knockout mice were created on the pro-atherogenic apoE⁻/⁻ background. Following 14 weeks of Western diet, aortic cholesterol levels were reduced 50% in 11βHSD1⁻/⁻/apoE⁻/⁻ mice vs. 11βHSD1⁺/⁺/apoE⁻/⁻ mice without changes in plasma cholesterol. Aortic 7-ketocholesterol content was reduced 40% in 11βHSD1⁻/⁻/apoE⁻/⁻ mice vs. control. In the aortic root, plaque size, necrotic core area and macrophage content were reduced ∼30% in 11βHSD1⁻/⁻/apoE⁻/⁻mice. Bone marrow transplantation from 11βHSD1⁻/⁻/apoE⁻/⁻ mice into apoE⁻/⁻ recipients reduced plaque area 39-46% in the thoracic aorta. In vivo foam cell formation was evaluated in thioglycollate-elicited peritoneal macrophages from 11βHSD1⁺/⁺/apoE⁻/⁻ and 11βHSD1⁻/⁻/apoE⁻/⁻ mice fed a Western diet for ∼5 weeks. Foam cell cholesterol levels were reduced 48% in 11βHSD1⁻/⁻/apoE⁻/⁻ mice vs. control. Microarray profiling of peritoneal macrophages revealed differential expression of genes involved in inflammation, stress response and energy metabolism. Several toll-like receptors (TLRs were downregulated in 11βHSD1⁻/⁻/apoE⁻/⁻ mice including TLR 1, 3 and 4. Cytokine release from 11βHSD1⁻/⁻/apoE⁻/⁻-derived peritoneal foam cells was attenuated following challenge with oxidized LDL. CONCLUSIONS: These findings suggest that 11βHSD1 inhibition may have

  6. 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...

  7. spd1672基因敲除显著影响肺炎链球菌的毒力%Spd1672 gene knockout significantly attenuates the virulence of Streptococcus pneumoniae

    Institute of Scientific and Technical Information of China (English)

    黄健; 黄美容; 吴凯峰; 朱杰华; 黎兵; 闵迅

    2015-01-01

    目的 研究spd1672基因在肺炎链球菌感染过程中的作用.方法 通过腹腔攻毒实验和细菌入血载量分析、细菌的粘附侵袭实验、全血杀菌实验以及相关细胞因子检测等观察spd1672基因敲除(D39△1672菌株)后对肺炎链球菌毒力的影响.结果D39△1672菌株感染组小鼠中位生存时间和生存率显著高于野生菌株组(P0.05), the spd1672 knockout strain showed significantly lower cell invasion ability than the wild-type strain (P<0.05). The spd1672 knockout strain also had a reduced resistance to whole blood cells, and thw mice infected with spd1672 knockout strain exhibit lower levels of serum inflammatory cytokines than those infected with the wild-type strain. Conclusion Spd1672 gene is importantly related to the virulence of S. pneumoniae and plays important roles in modulating bacterial invasion, resistance to whole blood cells and proinflammatory responses.

  8. 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.

  9. The role of GlcNAc-PI-de-N-acetylase gene by gene knockout through homologous recombination and its consequences on survival, growth and infectivity of Leishmania major in in vitro and in vivo conditions.

    Science.gov (United States)

    Almani, Pooya Ghasemi Nejad; Sharifi, Iraj; Kazemi, Bahram; Babaei, Zahra; Bandehpour, Mojgan; Salari, Samira; Dezaki, Ebrahim Saedi; Tohidi, Farideh; Mohammadi, Mohammad Ali

    2016-02-01

    At present, there are no efficacious vaccines or effective drugs against leishmaniasis; therefore new and innovative control methods are urgently required. One way to achieve this important goal is through using reverse genetic engineering to evaluate important enzymes, proteins and macromolecules. One of the most important enzymes for Glycosylphosphatidylinositol (GPI) biosynthetic pathways is GlcNAc-PI-de-N-acetylase (GPI12). The molecular constructs were cloned in Escherichia coli strain Top 10 and confirmed by molecular methods and were transfected by electroporation into Leishmania major. We demonstrated that two alleles of the GPI12 gene in L. major were successfully removed and enabling the generation of a null mutant, which supports the idea that GPI12 is not an essential gene for the growth and survival of Leishmania and the homozygous knockouts of Leishmania are able to survive. We were able to produce a mutant parasite that caused no damaged to the host. Further investigations are essential to check the safety profile in laboratory animals.

  10. Leukemogenesis in heterozygous PU.1 knockout mice.

    Science.gov (United States)

    Genik, Paula C; Vyazunova, Irina; Steffen, Leta S; Bacher, Jeffery W; Bielefeldt-Ohmann, Helle; McKercher, Scott; Ullrich, Robert L; Fallgren, Christina M; Weil, Michael M; Ray, F Andrew

    2014-09-01

    Most murine radiation-induced acute myeloid leukemias involve biallelic inactivation of the PU.1 gene, with one allele being lost through a radiation-induced chromosomal deletion and the other allele affected by a recurrent point mutation in codon 235 that is likely to be spontaneous. The short latencies of acute myeloid leukemias occurring in nonirradiated mice engineered with PU.1 conditional knockout or knockdown alleles suggest that once both copies of PU.1 have been lost any other steps involved in leukemogenesis occur rapidly. Yet, spontaneous acute myeloid leukemias have not been reported in mice heterozygous for a PU.1 knockout allele, an observation that conflicts with the understanding that the PU.1 codon 235 mutation is spontaneous. Here we describe experiments that show that the lack of spontaneous leukemia in PU.1 heterozygous knockout mice is not due to insufficient monitoring times or mouse numbers or the genetic background of the knockout mice. The results reveal that spontaneous leukemias that develop in mice of the mixed 129S2/SvPas and C57BL/6 background of knockout mice arise by a pathway that does not involve biallelic PU.1 mutation. In addition, the latency of radiation-induced leukemia in PU.1 heterozygous mice on a genetic background susceptible to radiation-induced leukemia indicates that the codon 235 mutation is not a rate-limiting step in radiation leukemogenesis driven by PU.1 loss.

  11. Cardiac structure and function during ageing in energetically compromised Guanidinoacetate N-methyltransferase (GAMT-knockout mice – a one year longitudinal MRI study

    Directory of Open Access Journals (Sweden)

    Clarke Kieran

    2008-02-01

    Full Text Available Abstract Background High-resolution magnetic resonance imaging (cine-MRI is well suited for determining global cardiac function longitudinally in genetically or surgically manipulated mice, but in practice it is seldom used to its full potential. In this study, male and female guanidinoacetate N-methyltransferase (GAMT knockout, and wild type littermate mice were subjected to a longitudinal cine-MRI study at four time points over the course of one year. GAMT is an essential enzyme in creatine biosynthesis, such that GAMT deficient mice are entirely creatine-free. Since creatine plays an important role in the buffering and transfer of high-energy phosphate bonds in the heart, it was hypothesized that lack of creatine would be detrimental for resting cardiac performance during ageing. Methods Measurements of cardiac structure (left ventricular mass and volumes and function (ejection fraction, stroke volume, cardiac output were obtained using high-resolution cine-MRI at 9.4 T under isoflurane anaesthesia. Results There were no physiologically significant differences in cardiac function between wild type and GAMT knockout mice at any time point for male or female groups, or for both combined (for example ejection fraction: 6 weeks (KO vs. WT: 70 ± 6% vs. 65 ± 7%; 4 months: 70 ± 6% vs. 62 ± 8%; 8 months: 62 ± 11% vs. 62 ± 6%; 12 months: 61 ± 7% vs. 59 ± 11%, respectively. Conclusion These findings suggest the presence of comprehensive adaptations in the knockout mice that can compensate for a lack of creatine. Furthermore, this study clearly demonstrates the power of cine-MRI for accurate non-invasive, serial cardiac measurements. Cardiac growth curves could easily be defined for each group, in the same set of animals for all time points, providing improved statistical power, and substantially reducing the number of mice required to conduct such a study. This technique should be eminently useful for following changes of cardiac structure and

  12. 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.

  13. Knockout crickets for the study of learning and memory: Dopamine receptor Dop1 mediates aversive but not appetitive reinforcement in crickets.

    Science.gov (United States)

    Awata, Hiroko; Watanabe, Takahito; Hamanaka, Yoshitaka; Mito, Taro; Noji, Sumihare; Mizunami, Makoto

    2015-11-02

    Elucidation of reinforcement mechanisms in associative learning is an important subject in neuroscience. In mammals, dopamine neurons are thought to play critical roles in mediating both appetitive and aversive reinforcement. Our pharmacological studies suggested that octopamine and dopamine neurons mediate reward and punishment, respectively, in crickets, but recent studies in fruit-flies concluded that dopamine neurons mediates both reward and punishment, via the type 1 dopamine receptor Dop1. To resolve the discrepancy between studies in different insect species, we produced Dop1 knockout crickets using the CRISPR/Cas9 system and found that they are defective in aversive learning with sodium chloride punishment but not appetitive learning with water or sucrose reward. The results suggest that dopamine and octopamine neurons mediate aversive and appetitive reinforcement, respectively, in crickets. We suggest unexpected diversity in neurotransmitters mediating appetitive reinforcement between crickets and fruit-flies, although the neurotransmitter mediating aversive reinforcement is conserved. This study demonstrates usefulness of the CRISPR/Cas9 system for producing knockout animals for the study of learning and memory.

  14. Gene knockout using transcription activator-like effector nucleases (TALENs) reveals that human NDUFA9 protein is essential for stabilizing the junction between membrane and matrix arms of complex I.

    Science.gov (United States)

    Stroud, David A; Formosa, Luke E; Wijeyeratne, Xiaonan W; Nguyen, Thanh N; Ryan, Michael T

    2013-01-18

    Transcription activator-like effector nucleases (TALENs) represent a promising approach for targeted knock-out of genes in cultured human cells. We used TALEN-technology to knock out the nuclear gene encoding NDUFA9, a subunit of mitochondrial respiratory chain complex I in HEK293T cells. Screening for the knock-out revealed a mixture of NDUFA9 cell clones that harbored partial deletions of the mitochondrial N-terminal targeting signal but were still capable of import. A cell line lacking functional copies of both NDUFA9 alleles resulted in a loss of NDUFA9 protein expression, impaired assembly of complex I, and cells incapable of growth in galactose medium. Cells lacking NDUFA9 contained a complex I subcomplex consisting of membrane arm subunits but not marker subunits of the matrix arm. Re-expression of NDUFA9 restored the defects in complex I assembly. We conclude that NDUFA9 is involved in stabilizing the junction between membrane and matrix arms of complex I, a late assembly step critical for complex I biogenesis and activity.

  15. Observation on biological characters of Streptococcus mutans luxS gene knockout mutant strain%变异链球菌luxS基因缺陷突变株生物学性状的初步观察

    Institute of Scientific and Technical Information of China (English)

    黄正蔚; 刘正; 马瑞; 唐子圣; 朱彩莲

    2008-01-01

    目的 为研究口腔主要致龋菌变异链球菌的种属间密度感应(quorum sensing)相关基因luxS对口腔生态的影响,构建此菌的luxS基因缺失突变株.方法 采用同源重组的方法,利用红霉素耐药基因erm置换变异链球菌基因组中的luxS基因,并在含抗性标记的选择性培养基上筛选出阳性克隆.初步研究该基因的缺失突变对变异链球菌在生长与生物被膜成熟分化中的作用.结果经PCR鉴定,luxS基因的置换突变位置正确,并能在体外稳定传代,突变株与野生株相比在达静止期后总菌数量上有明显差别,但在生物被膜的形成与分化上并未发现显著差异.结论 通过此研究建立了可稳定传代的变异链球菌luxS基因的缺失突变株,生长表型和生物被膜的形成与野生株无显著差异,为进一步研究此基因功能与调控机制提供了技术平台.%Objective To investigate the construction of Streptococcus mutans luxS gene knockout mutant which can act as the technical platform for following researches on luxS quorum sensing function in oral ecosystem.Methods Erythromycin resistance gene was inserted between two 1 kb fragments containing regions of DNA immediately upstream and downstream of the luxS translational start and stop codons.The resuhing construct was linearized and electro-transformed into Streptococcus mutans cells.After allelic exchange,the luxS gene knockout mutant strains were selected on 10μg/ml erythromycin plates,and compared the growth and biofilms formation of luxS knockout mutant with wild type strains.Results The luxSknockout mutant was confirmed by PCR,and it was also confirmed that this gene mutant could be stably passed through in vitro.The growth mode of luxS knockout mutant showed obvious difierences against that of wild type at stationary phase,the knockout mutant gained more bacteria cells growth.Conclusion Streptococcus mutans luxS gene has been successfully disrupted with allelic

  16. 大中型动物基因敲除技术的研究进展%The Development of Gene Knockout Technologies in Large and Medium Animal Models

    Institute of Scientific and Technical Information of China (English)

    刘雪静; 王欢; 严放; 高明明; 刘国庆; 黄薇

    2015-01-01

    基因敲除是20世纪80年代末发展起来的一门新技术,2007年获得诺贝尔生理或医学奖。然而在很长一段时间内,由于胚胎干细胞(embryonic stem cell,ES cell)体外的成功培养仅限于小鼠,该技术很难在其它动物种系中完成。2008年至今随着新 ES 细胞基因打靶、锌指核酸酶(zinc finger nucleases,ZFNs)、转录激活因子样效应物核酸酶(transcription activator-like effect nucleases, TALENs)和规律成簇的间隔短回文重复序列/Cas9内切酶(clusters of regularly interspased short pal-indromic repeats/Cas9,CRISPR/Cas9)等新技术的不断涌现,使在疾病研究中更接近于人类的大中型动物基因敲除成为可能。本综述将介绍近几年来以上几种基因敲除新技术在大中型动物上的成功应用及重大意义。%Technique of homologous recombination based gene targeting developed in the late 1 980s and won the Nobel Prize in Physiology or Medicine in 2007.However,this technique could only performed in mice which embryonic stem (ES)cells could keep in the potential of multifunction in vitro.Therefore gene knockout technology was difficult to be applied in other species of animals for a long time.Since 2008,with the development of the new technologies,such as the new ES cell gene targeting,zinc finger nucleases (ZFNs),transcription activator-like effector nucleases (TALENs)and clusters of regularly in-terspaced short palindromic repeats/Cas9 (CRISPR/Cas9),building gene knockout in large and medium animals models which are similar to human in disease research becomes possible.This review describes some new gene knockout technologies in large and medium animal models for recent years.

  17. 敲除成纤维细胞生长因子5基因对阿尔巴斯绒山羊胎儿皮肤成纤维细胞系的影响%Influences of FGF5 Gene Knockout to Arbas Cashmere Goat Fetal Skin Fibroblast Cell Line

    Institute of Scientific and Technical Information of China (English)

    高蓓; 马玉珍; 尹俊; 周欢敏

    2012-01-01

    In this study, in order to provide a nuclear for somatic cell nuclear transfer and production of transgenic animals, cationic liposome-mediated transfection of homologous recombination FGF5 gene knockout vector to somatic cell. After positive and negative selection obtained 51 cell clones, which remaining 12 clones after propagation, and ultimately get 4 positive cell clones by the molecular indentification of DNA and RNA levels, namely established the FGF5-knockouted Inner Mongolia Arbas cashmere goat fetal skin fibroblast cell line. Compared with normal somatic cell, the four FGF5 -knockouted positive cell clones had occurred very significant changes in cell morphology, traits and growth characteristics: bigger cell volume; fuzzy boundaries, reduced stereoscopic;growth rate dramatic decline;trypsin digestion time required was significantly increased. This study showed that these changes might be due to FGF5 gene knockout, cell transfection, drug selection and other roles.%本研究为体细胞核移植生产转基因动物提供核供体,以阳离子脂质体介导转染同源重组成纤维细胞生长因子5(fibroblast growth factor 5,FGF5)基因打靶载体至体细胞中,经正负双筛选获得了51个细胞克隆,扩繁后剩余12个克隆,最终经DNA及RNA水平的分子生物学鉴定得到4个阳性细胞克隆,即建立了敲除FGF5基因的内蒙古阿尔巴斯绒山羊胎儿皮肤成纤维细胞系.与普通细胞相比,所得的阳性细胞克隆在细胞形态、性状及生长特性等方面均发生了极其显著的变化:细胞体积增大;边界模糊,立体感降低;生长速率明显下降;胰蛋白酶消化所需时间明显增加.研究结果表明上述变化可能是受到了敲除FGF5基因、细胞转染和药物筛选作用等的影响所致.

  18. TFF3 knockout in human pituitary adenoma cell HP75 facilitates cell apoptosis via mitochondrial pathway.

    Science.gov (United States)

    Gao, Feng; Pan, Suxia; Liu, Bing; Zhang, Huanzhi

    2015-01-01

    Trefoil factor 3 (TFF3), a regulatory protein composed of 59 amino acids, has been suggested to be involved in pathogenesis, proliferation, differentiation, invasion, migration and apoptosis in multiple malignant tumors. This study thus investigated the effect of TFF3 knockout in human pituitary adenoma cell line HP75 on cell apoptosis and related pathways. RNA interference approach was used to knock down the expression of TFF3 protein. The gene silencing was validated by RNA denaturing gel electrophoresis and Western blotting. The effect of TFF3 knockout on cell apoptosis was analyzed by Western blotting and flow cytometry. TFF3 protein level in pituitary adenoma was about 3.61 ± 0.48 folds of that in normal tissues (P TFF3, the apoptotic ration was significantly elevated (P TFF3 protein knockout can facilitate apoptosis of human pituitary adenoma HP75 cells via mitochondrial pathway.

  19. TFF3 knockout in human pituitary adenoma cell HP75 facilitates cell apoptosis via mitochondrial pathway

    Science.gov (United States)

    Gao, Feng; Pan, Suxia; Liu, Bing; Zhang, Huanzhi

    2015-01-01

    Trefoil factor 3 (TFF3), a regulatory protein composed of 59 amino acids, has been suggested to be involved in pathogenesis, proliferation, differentiation, invasion, migration and apoptosis in multiple malignant tumors. This study thus investigated the effect of TFF3 knockout in human pituitary adenoma cell line HP75 on cell apoptosis and related pathways. RNA interference approach was used to knock down the expression of TFF3 protein. The gene silencing was validated by RNA denaturing gel electrophoresis and Western blotting. The effect of TFF3 knockout on cell apoptosis was analyzed by Western blotting and flow cytometry. TFF3 protein level in pituitary adenoma was about 3.61 ± 0.48 folds of that in normal tissues (P TFF3, the apoptotic ration was significantly elevated (P TFF3 protein knockout can facilitate apoptosis of human pituitary adenoma HP75 cells via mitochondrial pathway. PMID:26823779

  20. Recoiled Proton Tagged Knockout Reaction for 8He

    Institute of Scientific and Technical Information of China (English)

    曹中鑫; 叶沿林; 江栋兴; 郑涛; 李智焕; 华辉; 葛榆成; 李湘庆; 楼建玲; 肖军; 李奇特; 吕林辉; 李阔昂; 王赫; 乔锐; 游海波; 陈瑞九

    2012-01-01

    An experiment for knockout reaction induced by SHe beam at 82.5 MeV/nucleon on CH2 and C targets was carried out. The 6He and 4He core fragments at forward angles and the recoiled protons at large angles were detected coincidently. From this exclusive measurement the valence nucleon knockout mechanism and the core knockout mechanism are separated, which can be applied to the exclusive spectroscopic study on the structure of exotic nuclei.

  1. Study on Culture of Mouse Spermatogonial Stem Cells in Serum-Free KnockoutTM SR Medium%以KnockoutTM SR无血清培养基培养小鼠精原干细胞的研究

    Institute of Scientific and Technical Information of China (English)

    王庆忠

    2008-01-01

    设计并应用了KnockoutTM SR无血清培养基,在STO (SIM mouse embryo-derived thioguanine and ouabain resistant)饲养层上培养小鼠精原干细胞(spermatogonial stem cells, SSCs).结果表明小鼠SSCs在这一体系中能在短期内存活和形成克隆,并缓慢增殖,但不能更长时间地维持干细胞的不分化状态.

  2. CRISPR/Cas9 mediated knockout of the abdominal-A homeotic gene in the global pest, diamondback moth (Plutella xylostella).

    Science.gov (United States)

    Huang, Yuping; Chen, Yazhou; Zeng, Baosheng; Wang, Yajun; James, Anthony A; Gurr, Geoff M; Yang, Guang; Lin, Xijian; Huang, Yongping; You, Minsheng

    2016-08-01

    The diamondback moth, Plutella xylostella (L.), is a worldwide agricultural pest that has developed resistance to multiple classes of insecticides. Genetics-based approaches show promise as alternative pest management approaches but require functional studies to identify suitable gene targets. Here we use the CRISPR/Cas9 system to target a gene, abdominal-A, which has an important role in determining the identity and functionality of abdominal segments. We report that P. xylostella abdominal-A (Pxabd-A) has two structurally-similar splice isoforms (A and B) that differ only in the length of exon II, with 15 additional nucleotides in isoform A. Pxabd-A transcripts were detected in all developmental stages, and particularly in pupae and adults. CRISPR/Cas9-based mutagenesis of Pxabd-A exon I produced 91% chimeric mutants following injection of 448 eggs. Phenotypes with abnormal prolegs and malformed segments were visible in hatched larvae and unhatched embryos, and various defects were inherited by the next generation (G1). Genotyping of mutants demonstrated several mutations at the Pxabd-A genomic locus. The results indicate that a series of insertions and deletions were induced in the Pxabd-A locus, not only in G0 survivors but also in G1 individuals, and this provides a foundation for genome editing. Our study demonstrates the utility of the CRISPR/Cas9 system for targeting genes in an agricultural pest and therefore provides a foundation the development of novel pest management tools.

  3. Altered Expression of EPO Might Underlie Hepatic Hemangiomas in LRRK2 Knockout Mice.

    Science.gov (United States)

    Wu, Ben; Xiao, Kaifu; Zhang, Zhuohua; Ma, Long

    2016-01-01

    Parkinson's disease (PD) is a severe neurodegenerative disorder caused by progressive loss of dopaminergic neurons in the substantia nigra pars compacta of the midbrain. The molecular mechanism of PD pathogenesis is unclear. Mutations in the leucine-rich repeat kinase 2 (LRRK2) gene are a common genetic cause of familial and sporadic PD. However, studies on LRRK2 mutant mice revealed no visible dopaminergic neuronal loss in the midbrain. While surveying a LRRK2 knockout mouse strain, we found that old animals developed age-dependent hepatic vascular growths similar to cavernous hemangiomas. In livers of these hemangioma-positive LRRK2 knockout mice, we detected an increased expression of the HIF-2α protein and significant reactivation of the expression of the HIF-2α target gene erythropoietin (EPO), a finding consistent with a role of the HIF-2α pathway in blood vessel vascularization. We also found that the kidney EPO expression was reduced to 20% of the wild-type level in 18-month-old LRRK2 knockout mice. Unexpectedly, this reduction was restored to wild-type levels when the knockout mice were 22 months to 23 months old, implying a feedback mechanism regulating kidney EPO expression. Our findings reveal a novel function of LRRK2 in regulating EPO expression and imply a potentially novel relationship between PD genes and hematopoiesis.

  4. Cluster knockout reactions

    Indian Academy of Sciences (India)

    Arun K Jain; B N Joshi

    2014-04-01

    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 were existing as a free entity. Theoretically, the relatively softer interactions of the two outgoing particles with the residual nucleus lead to optical distortions and are treated in terms of distorted wave (DW) formalism. The long-range projectile–cluster interaction is accounted for, in terms of the finite range (FR) direct reaction formalism, as against the more commonly adopted zero-range (ZR) distorted wave impulse approximation (DWIA) formalism. Comparison of the DWIA calculations with the observed data provide information about the momentum distribution and the clustering spectroscopic factor of the target nucleus. Interesting results and some recent advancements in the area of (, 2) reactions and heavy cluster knockout reactions are discussed. Importance of the finite-range vertex and the final-state interactions are brought out.

  5. Comparison of brown and white adipose tissue fat fractions in ob, seipin, and Fsp27 gene knockout mice by chemical shift-selective imaging and (1)H-MR spectroscopy.

    Science.gov (United States)

    Peng, Xin-Gui; Ju, Shenghong; Fang, Fang; Wang, Yu; Fang, Ke; Cui, Xin; Liu, George; Li, Peng; Mao, Hui; Teng, Gao-Jun

    2013-01-15

    Brown adipose tissue (BAT) plays a key role in thermogenesis to protect the body from cold and obesity. White adipose tissue (WAT) stores excess energy in the form of triglycerides. To better understand the genetic effect on regulation of WAT and BAT, we investigated the fat fraction (FF) in two types of adipose tissues in ob/ob, human BSCL2/seipin gene knockout (SKO), Fsp27 gene knockout (Fsp27(-/-)), and wild-type (WT) mice in vivo using chemical shift selective imaging and (1)H-MR spectroscopy. We reported that the visceral fat volume in WAT was significantly larger in ob/ob mice, but visceral fat volumes were lower in SKO and Fsp27(-/-) mice compared with WT mice. BAT FF was significantly higher in ob/ob mice than the WT group and similar to that of WAT. In contrast, WAT FFs in SKO and Fsp27(-/-) mice were lower and similar to that of BAT. The adipocyte size of WAT in ob/ob mice and the BAT adipocyte size in ob/ob, SKO, and Fsp27 mice were significantly larger compared with WT mice. However, the WAT adipocyte size was significantly smaller in SKO mice than in WT mice. Positive correlations were observed between the adipocyte size and FFs of WAT and BAT. These results suggested that smaller adipocyte size correlates with lower FFs of WAT and BAT. In addition, the differences in FFs in WAT and BAT measured by MR methods in different mouse models were related to the different regulation effects of ob, seipin, or Fsp27 gene on developing WAT and BAT.

  6. 基因敲除技术在维生素D受体研究中的应用进展%Application progress in gene knock-out of vitamin D receptor

    Institute of Scientific and Technical Information of China (English)

    肖硕; 文九芳

    2016-01-01

    Gene knock-out,as a novel type of genetic engineering technology,has been more and more widely applied in the field of biomedicine.Vitamin D plays a variety of physiological roles through the me-diation by vitamin D receptor.Application of gene knock-out of vitamin D receptor can explicitly investigate multiple physiological functions of vitamin D,providing orientation and method for the biological research in the future.In this paper,the effects of gene knock-out of vitamin D receptor upon intestinal function,anti-tumor function and cardiovascular function were reviewed.%基因敲除技术是一种新的生物遗传工程技术,在生物和医学领域的应用日趋广泛。维生素 D 通过维生素 D 受体的介导发挥多种生理作用,借助维生素 D 受体的基因敲除技术可更清楚地研究维生素 D 的多种生理功能,为以后的生物研究提供新的方向与方法。该文就基因敲除技术应用于维生素 D 受体后对机体肠道功能、抗肿瘤功能、心血管功能方面影响的研究进展作一综述。

  7. Knockout of the dhfr-ts gene in Trypanosoma cruzi generates attenuated parasites able to confer protection against a virulent challenge.

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    Cecilia Perez Brandan

    2011-12-01

    Full Text Available BACKGROUND: Trypanosoma cruzi is a protozoan parasite that causes severe disease in millions of habitants of developing countries. Currently there is no vaccine to prevent this disease and the available drugs have the consequences of side effects. Live vaccines are likely to be more effective in inducing protection than recombinant proteins or DNA vaccines; however, safety problems associated to their use have been pointed out. In recent years, increasing knowledge on the molecular genetics of Trypanosomes has allowed the identification and elimination of genes that may be necessary for parasite infectivity and survival. In this sense, targeted deletion or disruption of specific genes in the parasite genome may protect against such reversion to virulent genotypes. METHODS AND FINDINGS: By targeted gene disruption we generated monoallelic mutant parasites for the dhfr-ts gene in a T. cruzi strain that has been shown to be naturally attenuated. In comparison to T. cruzi wild type epimastigotes, impairment in growth of dhfr-ts(+/- mutant parasites was observed and mutant clones displayed decreased virulence in mice. Also, a lower number of T. cruzi-specific CD8(+ T cells, in comparison to those induced by wild type parasites, was detected in mice infected with mutant parasites. However, no remarkable differences in the protective effect of TCC wild type versus TCC mutant parasites were observed. Mice challenged with virulent parasites a year after the original infection with the mutant parasites still displayed a significant control over the secondary infection. CONCLUSION: This study indicates that it is possible to generate genetically attenuated T. cruzi parasites able to confer protection against further T. cruzi infections.

  8. Altered reward circuitry in the norepinephrine transporter knockout mouse.

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    Joseph J Gallagher

    Full Text Available Synaptic levels of the monoamine neurotransmitters dopamine, serotonin, and norepinephrine are modulated by their respective plasma membrane transporters, albeit with a few exceptions. Monoamine transporters remove monoamines from the synaptic cleft and thus influence the degree and duration of signaling. Abnormal concentrations of these neuronal transmitters are implicated in a number of neurological and psychiatric disorders, including addiction, depression, and attention deficit/hyperactivity disorder. This work concentrates on the norepinephrine transporter (NET, using a battery of in vivo magnetic resonance imaging techniques and histological correlates to probe the effects of genetic deletion of the norepinephrine transporter on brain metabolism, anatomy and functional connectivity. MRS recorded in the striatum of NET knockout mice indicated a lower concentration of NAA that correlates with histological observations of subtle dysmorphisms in the striatum and internal capsule. As with DAT and SERT knockout mice, we detected minimal structural alterations in NET knockout mice by tensor-based morphometric analysis. In contrast, longitudinal imaging after stereotaxic prefrontal cortical injection of manganese, an established neuronal circuitry tracer, revealed that the reward circuit in the NET knockout mouse is biased toward anterior portions of the brain. This is similar to previous results observed for the dopamine transporter (DAT knockout mouse, but dissimilar from work with serotonin transporter (SERT knockout mice where Mn(2+ tracings extended to more posterior structures than in wildtype animals. These observations correlate with behavioral studies indicating that SERT knockout mice display anxiety-like phenotypes, while NET knockouts and to a lesser extent DAT knockout mice display antidepressant-like phenotypic features. Thus, the mainly anterior activity detected with manganese-enhanced MRI in the DAT and NET knockout mice is likely

  9. Role of MafA gene in insulin production-Analysis of heterozygous knockout mice%MafA基因部分敲除对于胰岛素产生的影响及机制研究

    Institute of Scientific and Technical Information of China (English)

    张川; 李波; 程妍; 姚宇航; 孙立娟; 高桥智

    2013-01-01

    Objective To clarify the role of MafA gene in development of MODY (maturity onset diabetes of the young) by studying insulin production,gene expression,and serum glucose level in heterozygous MafA gene knockout mice.Methods C57BL/6J mice were used as control animals,MafA gene heterozygous mice were analyzed.The distribution curve of blood sugar levels over time and serum insulin of heterozygous mice were determined by using IPGTT.The sensitivity of the mice to insulin was examined by injecting insulin assay.The expression levels of genes of MafA,insulin,pdX1,Beta2,and other genes of heterozygous mice were analyzed by semi-quantitative RT-PCR.Morphological changes in pancreatic tissue and α-and β-cell counts were obtained by using immunofluorescence/histological examination.Results (1) Two weeks after birth,MafA gene heterozygous mice began to show that the blood glucose level was increased,weight was reduced,and the amount of insulin secretion was clearly decreased (P<0.05 or P<0.01) while the insulin sensitivity did not change significantly.(2)The islet volume in MafA gene heterozygous mice was increased significantly as compared with the control group.However there were no significant changes in the number of pancreatic cells,distribution patterns,and the ratio of α and β cell.(3) Semi-quantitative RT-PCR detection showed that,compared with the control group,MafA gene level,the amount of insulin and Beta2 gene in MafA gene heterozygous mice were significantly reduced(all P<0.05),while no changes in the amount of glucagons and level of Pdx1 were found.Conclusions The blood glucose level of MafA gene heterozygous mice was raised early after birth.MafA gene is likely to be a new disease ralated gene of MODY.%目的 通过观察肌腱膜纤维肉瘤肿瘤基因同系物A(MafA)基因杂合子小鼠在胰岛素分泌、相关基因表达、血糖及血清胰岛素水平等方面的变化,探讨MafA基因在青少年起病的成人型糖

  10. Studies on localization and function of annexin A4a within urinary bladder epithelium using a mouse knockout model.

    Science.gov (United States)

    Hill, Warren G; Meyers, Susan; von Bodungen, Maximilian; Apodaca, Gerard; Dedman, John R; Kaetzel, Marcia A; Zeidel, Mark L

    2008-04-01

    Annexin A4 (anxA4) is a member of the Ca(2+)-dependent membrane-binding family of proteins implicated in the regulation of ion conductances, Ca(2+) homeostasis, and membrane trafficking. We demonstrate, in mice, that annexins 1-6 are present in whole bladder and exhibit differential expression in the urothelium. An anxA4a-knockout (anxA4a(-/-)) mouse model shows no protein in the urothelium by immunofluorescence and immunoblotting. In wild-type bladders, anxA4a in umbrella cells showed uniform cytoplasmic staining and some association with the nuclear membrane. Application of a hydrostatic pressure to bladders mounted in Ussing chambers resulted in redistribution of anxA4a from cytoplasm to cellular boundaries in the basal and intermediate cells but not in superficial umbrella cells. We hypothesized that anxA4a might be important for barrier function or for stretch-activated membrane trafficking. To test these hypotheses, we conducted a series of functional and morphological analyses on bladders from control and anxA4a(-/-) animals. The transepithelial resistances, water permeabilities, and urea permeabilities of anxA4a(-/-) bladders were not different from controls, indicating that barrier function was intact. Membrane trafficking in response to hydrostatic pressure as measured by capacitance increases was also normal for anxA4a(-/-) bladders. Cystometrograms performed on live animals showed that voiding frequency and intrabladder pressures were also not different. There were no differences in bladder surface morphology or cellular architecture examined by scanning and transmission electron microscopy, respectively. We conclude that loss of anxA4 from the urothelium does not affect barrier function, membrane trafficking, or normal bladder-voiding behavior.

  11. Knockout of the 15 kDa selenoprotein protects against chemically-induced aberrant crypt formation in mice.

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    Petra A Tsuji

    Full Text Available Evidence suggests that selenium has cancer preventive properties that are largely mediated through selenoproteins. Our previous observations demonstrated that targeted down-regulation of the 15 kDa selenoprotein (Sep15 in murine colon cancer cells resulted in the reversal of the cancer phenotype. The present study investigated the effect of Sep15 knockout in mice using a chemically-induced colon cancer model. Homozygous Sep15 knockout mice, and wild type littermate controls were given four weekly subcutaneous injections of azoxymethane (10 mg/kg. Sep15 knockout mice developed significantly (p<0.001 fewer aberrant crypt foci than controls demonstrating that loss of Sep15 protects against aberrant crypt foci formation. Dietary selenium above adequate levels did not significantly affect aberrant crypt foci formation in Sep15 knockout mice. To investigate molecular targets affected by loss of Sep15, gene expression patterns in colonic mucosal cells of knockout and wild type mice were examined using microarray analysis. Subsequent analyses verified that guanylate binding protein-1 (GBP-1 mRNA and protein expression were strongly upregulated in Sep15 knockout mice. GBP-1, which is expressed in response to interferon-γ, is considered to be an activation marker during inflammatory diseases, and up-regulation of GBP-1 in humans has been associated with a highly significant, increased five-year survival rate in colorectal cancer patients. In agreement with these studies, we observed a higher level of interferon-γ in plasma of Sep15 knockout mice. Overall, our results demonstrate for the first time, that Sep15 knockout mice are protected against chemically-induced aberrant crypt foci formation and that Sep15 appears to have oncogenic properties in colon carcinogenesis in vivo.

  12. IdealKnock: A framework for efficiently identifying knockout strategies leading to targeted overproduction.

    Science.gov (United States)

    Gu, Deqing; Zhang, Cheng; Zhou, Shengguo; Wei, Liujing; Hua, Qiang

    2016-04-01

    In recent years, computer aided redesigning methods based on genome-scale metabolic network models (GEMs) have played important roles in metabolic engineering studies; however, most of these methods are hindered by intractable computing times. In particular, methods that predict knockout strategies leading to overproduction of desired biochemical are generally unable to do high level prediction because the computational time will increase exponentially. In this study, we propose a new framework named IdealKnock, which is able to efficiently evaluate potentials of the production for different biochemical in a system by merely knocking out pathways. In addition, it is also capable of searching knockout strategies when combined with the OptKnock or OptGene framework. Furthermore, unlike other methods, IdealKnock suggests a series of mutants with targeted overproduction, which enables researchers to select the one of greatest interest for experimental validation. By testing the overproduction of a large number of native metabolites, IdealKnock showed its advantage in successfully breaking through the limitation of maximum knockout number in reasonable time and suggesting knockout strategies with better performance than other methods. In addition, gene-reaction relationship is well considered in the proposed framework.

  13. Single and double metallothionein knockout in the nematode C. elegans reveals cadmium dependent and independent toxic effects on life history traits

    Energy Technology Data Exchange (ETDEWEB)

    Hughes, Sam [School of Biosciences, Cardiff University, Main Building, Park Place, Cardiff CF10 3TL (United Kingdom); School of Biomedical and Health Sciences, Pharmaceutical Sciences Research Division, King' s College London, 150 Stamford Street, London SE1 9NH (United Kingdom); Stuerzenbaum, Stephen R. [School of Biosciences, Cardiff University, Main Building, Park Place, Cardiff CF10 3TL (United Kingdom) and School of Biomedical and Health Sciences, Pharmaceutical Sciences Research Division, King' s College London, 150 Stamford Street, London SE1 9NH (United Kingdom)]. E-mail: stephen.sturzenbaum@kcl.ac.uk

    2007-01-15

    The genome of the nematode Caenorhabditis elegans contains two metallothionein genes, both involved in metal homeostasis and/or detoxification. Single metallothionein knockout mutants have been created and now, for the first time, a double mutant has been isolated. Life history studies in the presence or absence of cadmium showed that all metallothionein mutants are viable. Although cadmium did not influence longevity, a dose dependent reduction in total brood size and volumetric growth was observed in wild type animals, which was magnified in single knockouts and further exacerbated in the double knockout. However, the metallothionein deletion caused two effects that are independent of cadmium exposure, namely all knockout strains displayed a reduced total brood size and the deletion of both metallothionein loci caused a significant reduction in volumetric growth. In summary, metallothionein is undoubtedly an important player in cadmium detoxification, but evidently also an important factor in cadmium independent pathways. - Metallothionein is a modifier of life-history parameters.

  14. 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.

  15. Essential role of chicken ovalbumin upstream promoter-transcription factor II in insulin secretion and insulin sensitivity revealed by conditional gene knockout.

    Science.gov (United States)

    Bardoux, Pascale; Zhang, Pili; Flamez, Daisy; Perilhou, Anaïs; Lavin, Tiphaine Aguirre; Tanti, Jean-François; Hellemans, Karine; Gomas, Emmanuel; Godard, Cécile; Andreelli, Fabrizio; Buccheri, Maria Antonietta; Kahn, Axel; Le Marchand-Brustel, Yannick; Burcelin, Rémy; Schuit, Frans; Vasseur-Cognet, Mireille

    2005-05-01

    Chicken ovalbumin upstream promoter-transcription factor II (COUP-TFII) has been implicated in the control of blood glucose by its potent effect on expression and signaling of various nuclear receptors. To understand the role of COUP-TFII in glucose homeostasis, conditional COUP-TFII-deficient mice were generated and crossed with mice expressing Cre under the control of rat insulin II gene promoter, resulting in deletion of COUP-TFII in pancreatic beta-cells. Homozygous mutants died before birth for yet undetermined reasons. Heterozygous mice appeared healthy at birth and showed normal growth and fertility. When challenged intraperitoneally, the animals had glucose intolerance associated with reduced glucose-stimulated insulin secretion. Moreover, these heterozygous mice presented a mild increase in fasting and random-fed circulating insulin levels. In accordance, islets isolated from these animals exhibited higher insulin secretion in low glucose conditions and markedly decreased glucose-stimulated insulin secretion. Their pancreata presented normal microscopic architecture and insulin content up to 16 weeks of study. Altered insulin secretion was associated with peripheral insulin resistance in whole animals. It can be concluded that COUP-TFII is a new, important regulator of glucose homeostasis and insulin sensitivity.

  16. 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.

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

    Science.gov (United States)

    Wang, Yu; Fan, Nana; Song, Jun; Zhong, Juan; Guo, Xiaogang; Tian, Weihua; Zhang, Quanjun; Cui, Fenggong; Li, Li; Newsome, Philip N; Frampton, Jon; Esteban, Miguel A; Lai, Liangxue

    2014-01-01

    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.

  18. Rapid phenotyping of knockout mice to identify genetic determinants of bone strength

    Science.gov (United States)

    Freudenthal, Bernard; Logan, John; Croucher, Peter I

    2016-01-01

    The genetic determinants of osteoporosis remain poorly understood, and there is a large unmet need for new treatments in our ageing society. Thus, new approaches for gene discovery in skeletal disease are required to complement the current genome-wide association studies in human populations. The International Knockout Mouse Consortium (IKMC) and the International Mouse Phenotyping Consortium (IMPC) provide such an opportunity. The IKMC generates knockout mice representing each of the known protein-coding genes in C57BL/6 mice and, as part of the IMPC initiative, the Origins of Bone and Cartilage Disease project identifies mutants with significant outlier skeletal phenotypes. This initiative will add value to data from large human cohorts and provide a new understanding of bone and cartilage pathophysiology, ultimately leading to the identification of novel drug targets for the treatment of skeletal disease. PMID:27535945

  19. NR4A1 (Nur77 mediates thyrotropin-releasing hormone-induced stimulation of transcription of the thyrotropin β gene: analysis of TRH knockout mice.

    Directory of Open Access Journals (Sweden)

    Yasuyo Nakajima

    Full Text Available Thyrotropin-releasing hormone (TRH is a major stimulator of thyrotropin-stimulating hormone (TSH synthesis in the anterior pituitary, though precisely how TRH stimulates the TSHβ gene remains unclear. Analysis of TRH-deficient mice differing in thyroid hormone status demonstrated that TRH was critical for the basal activity and responsiveness to thyroid hormone of the TSHβ gene. cDNA microarray and K-means cluster analyses with pituitaries from wild-type mice, TRH-deficient mice and TRH-deficient mice with thyroid hormone replacement revealed that the largest and most consistent decrease in expression in the absence of TRH and on supplementation with thyroid hormone was shown by the TSHβ gene, and the NR4A1 gene belonged to the same cluster as and showed a similar expression profile to the TSHβ gene. Immunohistochemical analysis demonstrated that NR4A1 was expressed not only in ACTH- and FSH- producing cells but also in thyrotrophs and the expression was remarkably reduced in TRH-deficient pituitary. Furthermore, experiments in vitro demonstrated that incubation with TRH in GH4C1 cells increased the endogenous NR4A1 mRNA level by approximately 50-fold within one hour, and this stimulation was inhibited by inhibitors for PKC and ERK1/2. Western blot analysis confirmed that TRH increased NR4A1 expression within 2 h. A series of deletions of the promoter demonstrated that the region between bp -138 and +37 of the TSHβ gene was responsible for the TRH-induced stimulation, and Chip analysis revealed that NR4A1 was recruited to this region. Conversely, knockdown of NR4A1 by siRNA led to a significant reduction in TRH-induced TSHβ promoter activity. Furthermore, TRH stimulated NR4A1 promoter activity through the TRH receptor. These findings demonstrated that 1 TRH is a highly specific regulator of the TSHβ gene, and 2 TRH mediated induction of the TSHβ gene, at least in part by sequential stimulation of the NR4A1-TSHβ genes through a PKC and

  20. Regulation of gene expression by dietary Ca2+ in kidneys of 25-hydroxyvitamin D3-1 alpha-hydroxylase knockout mice.

    NARCIS (Netherlands)

    Hoenderop, J.G.J.; Chon, H.; Gkika, D.; Bluyssen, H.A.; Holstege, F.C.; St. Arnaud, R.; Braam, B.; Bindels, R.J.M.

    2004-01-01

    BACKGROUND: Pseudovitamin D deficiency rickets (PDDR) is an autosomal disease, characterized by undetectable levels of 1,25-dihydroxyvitamin D3 (1,25(OH)2D3), rickets and secondary hyperparathyroidism. Mice in which the 25-hydroxyvitamin D3-1 alpha-hydroxylase (1 alpha-OHase) gene was inactivated, p

  1. Dietary calcium and 1,25-dihydroxyvitamin D3 regulate transcription of calcium transporter genes in calbindin-D9k knockout mice.

    Science.gov (United States)

    Ko, Sang-Hwan; Lee, Geun-Shik; Vo, Thuy T B; Jung, Eui-Man; Choi, Kyung-Chul; Cheung, Ki-Wha; Kim, Jae Wha; Park, Jong-Gil; Oh, Goo Taeg; Jeung, Eui-Bae

    2009-04-01

    The effect(s) of oral calcium and vitamin D(3) were examined on the expression of duodenal and renal active calcium transport genes, i.e., calbindin-D9k (CaBP-9k) and calbindin-D28k (CaBP-28k), transient receptor potential cation channels (TRPV5 and TRPV6), Na(+)/Ca(2+) exchanger 1 (NCX1) and plasma membrane calcium ATPase 1b (PMCA1b), in CaBP-9k KO mice. Wild-type (WT) and KO mice were provided with calcium and vitamin D(3)-deficient diets for 10 weeks. The deficient diet significantly decreased body weights compared with the normal diet groups. The serum calcium concentration of the WT mice was decreased by the deficient diet but was unchanged in the KO mice. The deficient diet significantly increased duodenal transcription of CaBP-9k and TRPV6 in the WT mice, but no alteration was observed in the KO mice. In the kidney, the deficient diet significantly increased renal transcripts of CaBP-9k, TRPV6, PMCA1b, CaBP-28k and TRPV5 in the WT mice but did not alter calcium-relating genes in the KO mice. Two potential mediators of calcium-processing genes, vitamin D receptor (VDR) and parathyroid hormone receptor (PTHR), have been suggested to be useful for elucidating these differential regulations in the calcium-related genes of the KO mice. Expression of VDR was not significantly affected by diet or the KO mutation. Renal PTHR mRNA levels were reduced by the diet, and reduced expression was also seen in the KO mice given the normal diet. Taken together, these results suggest that the active calcium transporting genes in KO mice may have resistance to the deficiency diet of calcium and vitamin D(3).

  2. 心房钠尿肽基因敲除小鼠的鉴定%Identification of Atrial Natriuretic Peptide Gene Knockout (ANP-/-)Mice

    Institute of Scientific and Technical Information of China (English)

    杨扬; 王丽京; 李斌; 叶杰; 亓翠玲; 何晓东; 李江超; 章倩倩; 黄韧; 张钰

    2015-01-01

    研究心房钠尿肽基因敲除小鼠(ANP-/-小鼠)的生物学及病理学特性。 ANP-/-小鼠与C57BL/6小鼠饲养于SPF级环境中,观察小鼠的繁育状况及其生物学特性,选取合适时间剖杀小鼠,通过HE染色观察脏器形态及组织结构。ANP-/-小鼠的繁殖周期比C57BL/6长,产仔率较低;ANP-/-小鼠肝脏、肺脏、脾脏较C57BL/6小鼠的有明显炎症反应,但是C57BL/6小鼠未见明显的病理改变。提示ANP基因的缺失可能与炎症发生有关。说明ANP-/-小鼠繁殖较慢、产仔率低,且正常繁殖的普通小鼠不会引起器官的病理学改变。但作为一种在心血管、代谢疾病上的动物模型,并与炎症甚至肿瘤有可能的未知联系的转基因动物,其很有研究和探索价值。%To investigate the biological features of new transgenic mice (ANP- /- mice) and compare its pathological features with normal mice .ANP- /- mice and C57BL/6 mice (normal control mice) were housed in the same SPF environment to observe the multiplication and study their biological characteris‐tics .The histological morphology and structure of organs were compared with normal mice .The ANP- /-mice have longer reproductive cycle and lower birth rate ;Moreover ,ANP-/- mice show slightly higher in‐flammatory response than C57BL/6 mice ,suggesting that ANP gene may associated with inflammation . The reproduction and birth rate of ANP - /- mice are slow ,but as the animal model used in cardiovascular and metabolic disease ,even inflammation or cancer ,they have potential research and exploration value .

  3. TALEN-based knockout library for human microRNAs.

    Science.gov (United States)

    Kim, Young-Kook; Wee, Gabbine; Park, Joha; Kim, Jongkyu; Baek, Daehyun; Kim, Jin-Soo; Kim, V Narry

    2013-12-01

    Various technical tools have been developed to probe the functions of microRNAs (miRNAs), yet their application has been limited by low efficacy and specificity. To overcome the limitations, we used transcription activator-like effector nucleases (TALENs) to knock out human miRNA genes. We designed and produced a library of 540 pairs of TALENs for 274 miRNA loci, focusing on potentially important miRNAs. The knockout procedure takes only 2-4 weeks and can be applied to any cell type. As a case study, we generated knockout cells for two related miRNAs, miR-141 and miR-200c, which belong to the highly conserved miR-200 family. Interestingly, miR-141 and miR-200c, despite their overall similarity, suppress largely nonoverlapping groups of targets, thus suggesting that functional miRNA-target interaction requires strict seed-pairing. Our study illustrates the potency of TALEN technology and provides useful resources for miRNA research.

  4. 利用基因敲除小鼠研究发热机制的进展%Progress in studying the mechanism of fever using knockout mice

    Institute of Scientific and Technical Information of China (English)

    李沧海; 霍海如; 姜廷良

    2002-01-01

    Increasing evidence suggests that a complex net-work of fever induction pathways in mammalian exists.In this article,the overview of recent studies on the mechanism of fever induced by different pyrogens using IL-1,IL-1R,ICE,IL-1ra,IL-1RacP,IL-6,IL-10,TNFR,cPLA2,COX,EP,AT2,iNOS and D2/3 knockout mice is presented.Hyperthermia respond to localized infection/inflammation(e.g.,scinjection of turpentine) is mediated by IL-1β and IL-6 in turn.While fever induced by systemic infection/inflammation(e.g.,treatment with LPS intraperitoneally)varies with the different doses of pyrogens administered.Fever caused by a low dose of LPS administered ip is IL-6 dependent,but the IL-6 independent pathway is crucial for the fever evoked by a high dose of LPS.Febrile responses during both local and systemic infection/inflammation develop totally through central PGE2 dependent mechanism,but some stress induced hyperthermia otherwise.

  5. Elimination of manganese(II,III) oxidation in Pseudomonas putida GB-1 by a double knockout of two putative multicopper oxidase genes.

    Science.gov (United States)

    Geszvain, Kati; McCarthy, James K; Tebo, Bradley M

    2013-01-01

    Bacterial manganese(II) oxidation impacts the redox cycling of Mn, other elements, and compounds in the environment; therefore, it is important to understand the mechanisms of and enzymes responsible for Mn(II) oxidation. In several Mn(II)-oxidizing organisms, the identified Mn(II) oxidase belongs to either the multicopper oxidase (MCO) or the heme peroxidase family of proteins. However, the identity of the oxidase in Pseudomonas putida GB-1 has long remained unknown. To identify the P. putida GB-1 oxidase, we searched its genome and found several homologues of known or suspected Mn(II) oxidase-encoding genes (mnxG, mofA, moxA, and mopA). To narrow this list, we assumed that the Mn(II) oxidase gene would be conserved among Mn(II)-oxidizing pseudomonads but not in nonoxidizers and performed a genome comparison to 11 Pseudomonas species. We further assumed that the oxidase gene would be regulated by MnxR, a transcription factor required for Mn(II) oxidation. Two loci met all these criteria: PputGB1_2447, which encodes an MCO homologous to MnxG, and PputGB1_2665, which encodes an MCO with very low homology to MofA. In-frame deletions of each locus resulted in strains that retained some ability to oxidize Mn(II) or Mn(III); loss of oxidation was attained only upon deletion of both genes. These results suggest that PputGB1_2447 and PputGB1_2665 encode two MCOs that are independently capable of oxidizing both Mn(II) and Mn(III). The purpose of this redundancy is unclear; however, differences in oxidation phenotype for the single mutants suggest specialization in function for the two enzymes.

  6. Knockout AR in Prostate

    Science.gov (United States)

    2007-10-01

    Communicated by Henry Lardy, University of Wisconsin-Madison, Madison, WI, June 15, 2007 (received for review March 22, 2007)Accepted on May 17, 2007...Cardiff RD, Cunha GR, et al. (1999) Genes Dev 13:966–977. 19. Kim MJ, Bhatia-Gaur R, Banach- Petrosky WA, Desai N, Wang Y, Hayward SW, Cunha GR, Cardiff

  7. Identification of novel knockout targets for improving terpenoids biosynthesis in Saccharomyces cerevisiae.

    Science.gov (United States)

    Sun, Zhiqiang; Meng, Hailin; Li, Jing; Wang, Jianfeng; Li, Qian; Wang, Yong; Zhang, Yansheng

    2014-01-01

    Many terpenoids have important pharmacological activity and commercial value; however, application of these terpenoids is often limited by problems associated with the production of sufficient amounts of these molecules. The use of Saccharomyces cerevisiae (S. cerevisiae) for the production of heterologous terpenoids has achieved some success. The objective of this study was to identify S. cerevisiae knockout targets for improving the synthesis of heterologous terpeniods. On the basis of computational analysis of the S. cerevisiae metabolic network, we identified the knockout sites with the potential to promote terpenoid production and the corresponding single mutant was constructed by molecular manipulations. The growth rates of these strains were measured and the results indicated that the gene deletion had no adverse effects. Using the expression of amorphadiene biosynthesis as a testing model, the gene deletion was assessed for its effect on the production of exogenous terpenoids. The results showed that the dysfunction of most genes led to increased production of amorphadiene. The yield of amorphadiene produced by most single mutants was 8-10-fold greater compared to the wild type, indicating that the knockout sites can be engineered to promote the synthesis of exogenous terpenoids.

  8. Universal statistics of the knockout tournament

    OpenAIRE

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

    2013-01-01

    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 tourn...

  9. Dysregulation of dopamine-dependent mechanisms as a determinant of hypertension: studies in dopamine receptor knockout mice.

    Science.gov (United States)

    Zeng, Chunyu; Armando, Ines; Luo, Yingjin; Eisner, Gilbert M; Felder, Robin A; Jose, Pedro A

    2008-02-01

    Dopamine plays an important role in the pathogenesis of hypertension by regulating epithelial sodium transport and by interacting with vasoactive hormones/humoral factors, such as aldosterone, angiotensin, catecholamines, endothelin, oxytocin, prolactin pro-opiomelancortin, reactive oxygen species, renin, and vasopressin. Dopamine receptors are classified into D(1)-like (D(1) and D(5)) and D(2)-like (D(2), D(3), and D(4)) subtypes based on their structure and pharmacology. In recent years, mice deficient in one or more of the five dopamine receptor subtypes have been generated, leading to a better understanding of the physiological role of each of the dopamine receptor subtypes. This review summarizes the results from studies of various dopamine receptor mutant mice on the role of individual dopamine receptor subtypes and their interactions with other G protein-coupled receptors in the regulation of blood pressure.

  10. EERα基因敲除小鼠的繁育及子代小鼠基因型的鉴定%Breeding of ERα gene knockout mice and genotype identification of their filial generation

    Institute of Scientific and Technical Information of China (English)

    王强; 钱文溢; 刘景丽; 朱勤; 程洁; 王宇; 丁海霞; 肖杭

    2011-01-01

    目的 探讨雌激素受体α(ERα)基因敲除小鼠的优化繁育方法及ERα基因敲除小鼠子代鼠的鉴定方法,建立ERα基因敲除小鼠模型,为进一步研究ERα蛋白的功能奠定基础.方法 用4种不同的交配方式观察子代鼠的各表型比率及雌、雄性ERα基因突变纯合子小鼠的繁殖能力;从子鼠鼠尾中提取基因组DNA,用PCR方法扩增ERα基因片段,琼脂糖凝胶电泳后观察结果.HE染色观察雌、雄性ERα小鼠生殖系统表型变化.结果 WT、ERα、ERα各表型小鼠互交繁殖结果基本符合孟德尔遗传规律,且雌、雄性ERα小鼠无繁殖能力.与WT比较,雄性ERα小鼠睾丸脏器系数降低,睾丸病理变化表现为生精小管管腔膨胀,生精细胞层变薄,且排列不规则;雌性ERα小鼠子宫脏器系数降低,子宫和卵巢病变明显,表现为:子宫浆膜、肌层、内膜层细胞排列不规则,卵巢有囊性病变、充血,无黄体.结论 雌、雄性ERα小鼠交配是繁育ERα小鼠的较好方法;实验所用PCR方法能够精确鉴定ERα小鼠,ERα小鼠的获得为ERα蛋白功能的实验研究提供了较理想的动物模型.%Objective To breed and identify estrogen receptor α (ERα) knockout mice and to establish an animal experimental model to further study the important role of ERα. Methods ERα knockout mice were paired in different ways. Genomic DNA was isolated from tails and analyzed by PCR. Results The ratio of the offspring genotypes fits the Mendel's laws. The male and female ERα knockout homozygote (ERα-/- ) mice are infertile. The testes, uteri and ovaries were significantly different between ERα -/- and wild-type mice. The testis and uterus weights of ERα-/- mice were significantly lower than that of wild-type mice. Some seminiferous tubules had a dilated lumen and a thin lining layer of disorganized seminiferous epithelium with few spermatogenic cells. Histological examination showed the presence of stromal

  11. Thalidomide influences atherogenesis in aortas of ApoE(-/-)/LDLR (-/-) double knockout mice: a nano-CT study.

    Science.gov (United States)

    Kampschulte, Marian; Gunkel, Irina; Stieger, Philipp; Sedding, Daniel G; Brinkmann, Anne; Ritman, Erik L; Krombach, Gabriele A; Langheinrich, Alexander C

    2014-04-01

    Plaque progression in atherosclerosis is closely connected to angiogenesis due to vasa vasorum (VV) growth. Objective of this study was to determine the unknown long-term effect of thalidomide on adventitial VV neovascularization and plaque progression using nano-focussed computed tomography (nano-CT). Proliferation and migration assays in human coronary artery endothelial cells (HCAEC) measured number of viable cells after incubation with thalidomide. Male ApoE(-/-)/LDLR(-/-) (AL) mice (n = 5) received a thalidomide containing western diet (WD) over 29 weeks. Another five male AL mice (WD without thalidomide) served as control group. Descending aortas were scanned with nano-CT at (1.5 μm)(3) isotropic voxel size. Number and area of adventitial VV as well as plaque cross sectional area were measured. Results were complemented by histology. Thalidomide inhibited proliferation and migration of HCAEC dose-dependently. VV neovascularization decreased in number per cross section (7.66 ± 0.301 vs. 8.62 ± 0.164, p thalidomide (0.57 ± 0.0187 vs. 0.803 ± 0.0148 mm(2), p thalidomide. Therefore, nano-CT can be considered as a new method to detect therapeutic effects in experimental models of atherosclerosis.

  12. A stringent dual control system overseeing transcription and activity of the Cre recombinase for the liver-specific conditional gene knock-out mouse model

    Institute of Scientific and Technical Information of China (English)

    Yu Wu; Yinghua He; Hongyu Zhang; Xinlan Dai; Xiaoyu Zhou; Jun Gu; Guan Wang; Jingde Zhu

    2008-01-01

    Liver cancer is one of the most threatening diseases in Chinese population. Just like in other tissues, tumor initiation and development in liver involve multiple steps of genetic and epigenetic alterations with several unknown details. However, unlike in other tissues, a tis- sue specific inducible Cre recombinase system that allows temporal and spatial deletion of a target DNA fragment is still not available for in vivo functional gene annotation in hepatocytes. In our pursuit to establish such a mouse model, we designed a dual inducible Cre transgene system and tested it in cultured cells. By combining a CCAAT/enhancer binding protein β (C/EBP β) promoter derived Tet-off expression system and the estrogen receptor (ER) mediated functional control, we show a desirable profile of both hepatocyte-specificity and regulability of the Cre expression in a series of critical assessments in the cell culture system, which provides confidence in continua- tion of our ongoing pursuit in mouse.

  13. An Analysis of the Gene Expression in Mitf-m Knockout Mice%Mitf-m敲除小鼠的基因差异表达分析

    Institute of Scientific and Technical Information of China (English)

    王克双; 王晓东; 任丽丽; 陈磊; 塞娜; 郭维维; 杨仕明

    2016-01-01

    目的 使用RNA-Seq技术分析Mitf-m敲除鼠与野生鼠的血管纹转录组,研究Mitf-m基因敲除后的差异表达基因及相关改变的分子机制.方法 分别取Mitf-m敲除鼠(Mitfm’△M/mi-△M;MM组)与野生鼠(Mitf-m+/+;WW组)的血管纹进行总RNA提取;制备cDNA文库,用Illumina HiSeq 2000测序系统行高通量测序.利用软件Tophat 2.2.0将clean reads比对到参考基因组;分别用软件RSeQS-2.3.2和cufflinks来检测测序结果的均一性和基因表达水平.使用edgeR和DESeq程序筛选差异表达基因(differential expressed genes,DEGs);选择下调DEGs,用KOBAS2.0进行基因本体(gene ontology,GO)和京都基因与基因组百科全书(Kyoto Encyclopedia of Genes and Genomes,KEGG)代谢途径的富集分析.结果 MM组与WW组在参考基因组上mapping的clean reads数分别为42463888和3971 8542,分别有88.7%和87.4%的reads是唯一映射,说明RNA-Seq结果可靠.DEGs筛查结果表明,相对于WW组,Mitf-m敲除鼠血管纹有45个DEGs,上调表达基因有7个,下调表达基因有38个.GO富集分析发现下调表达基因与黑色素的合成和代谢过程、色素沉着有关,值得关注的是与内向整流钾离子通道Kcnj 10和Kcnj13相关.KEGG富集分析显示下调表达基因主要富集于黑色素生成通路.结论 RNA-Seq分析拓展了Mitf-m基因调控网,为探究Mitf-m突变所致听力-色素综合征的分子机制及特异性研究Mitf不同转录子的功能奠定了基础.

  14. Retinoid-related orphan receptor γ (RORγ) adult induced knockout mice develop lymphoblastic lymphoma.

    Science.gov (United States)

    Liljevald, Maria; Rehnberg, Maria; Söderberg, Magnus; Ramnegård, Marie; Börjesson, Jenny; Luciani, Donatella; Krutrök, Nina; Brändén, Lena; Johansson, Camilla; Xu, Xiufeng; Bjursell, Mikael; Sjögren, Anna-Karin; Hornberg, Jorrit; Andersson, Ulf; Keeling, David; Jirholt, Johan

    2016-11-01

    RORγ is a nuclear hormone receptor which controls polarization of naive CD4(+) T-cells into proinflammatory Th17 cells. Pharmacological antagonism of RORγ has therapeutic potential for autoimmune diseases; however, this mechanism may potentially carry target-related safety risks, as mice deficient in Rorc, the gene encoding RORγ, develop T-cell lymphoma with 50% frequency. Due to the requirement of RORγ during development, the Rorc knockout (KO) animals lack secondary lymphoid organs and have a dysregulation in the generation of CD4+ and CD8+ T cells. We wanted to extend the evaluation of RORγ deficiency to address the question whether lymphomas, similar to those observed in the Rorc KO, would develop in an animal with an otherwise intact adult immune system. Accordingly, we designed a conditional RORγ knockout mouse (Rorc CKO) where the Rorc locus could be deleted in adult animals. Based on these studies we can confirm that these animals also develop lymphoma in a similar time frame as embryonic Rorc knockouts. This study also suggests that in animals where the gene deletion is incomplete, the thymus undergoes a rapid selection process replacing Rorc deficient cells with remnant thymocytes carrying a functional Rorc locus and that subsequently, these animals do not develop lymphoblastic lymphoma.

  15. 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

  16. TRPV4 mediates afferent pathways in the urinary bladder. A spinal c-fos study showing TRPV1 related adaptations in the TRPV4 knockout mouse.

    Science.gov (United States)

    Janssen, Dick A W; Hoenderop, Joost G; Heesakkers, John P F A; Schalken, Jack A

    2016-10-01

    The role of transient receptor potential vanilloid subtype 4 (TRPV4) channels in urinary bladder afferent neural pathways was investigated using spinal c-fos measurements in mice. Anesthetized wild type and TRPV4 knockout (-/-) mice underwent noxious bladder distention and treatment with either intravesical instillation with lipopolysaccharide (LPS), or the TRPV1 agonist resiniferatoxin (RTX), vehicle or an intraperitoneal injected TRPV4 antagonist (HC067047). Mice underwent paraformaldehyde perfusion for rapid fixation and L6-S1 spinal cord sections were removed followed by immunohistochemical staining for c-fos. A number of c-fos expressing neurons in the dorsal horns of L6-S1 spinal cord transections were quantified. Groups were compared using univariate ANOVA. Even with the absence of bladder inflammation on H&E, the TRPV4 -/- mice still have a significant twofold higher c-fos expression (n = 39, SD 2) after noxious bladder distention compared to wild type mice (n = 20, SD 3). A twofold increase in c-fos expression was observed after LPS treatment in wild types (n = 42, SD 5), but no increase was seen in TRPV4 -/- mice (n = 42, SD 2). After desensitization of primary afferent C-nerve fibers with RTX, c-fos expression in TRPV4-/- mice decreased significantly (threefold) (n = 12, SD 4). Results imply that TRPV4 channels are important for bladder afferent signaling. TRPV4 -/- mice bladders generate more noxious sensory output, which is predominantly mediated through TRPV1 expressing high threshold nerve fibers. This study reveals TRPV1 related adaptive changes in afferent pathways of the TRPV4 -/- mouse. We propose that this effect is caused by a congenital impairment of low threshold nerves that mediate normal bladder filling sensations.

  17. Investigation on the mechanism of descended reproductive function in FMR1 gene knockout male mice%FMR1基因敲除雄鼠生殖功能下降的机制探讨

    Institute of Scientific and Technical Information of China (English)

    叶球仙; 杨洁; 罗虹; 陈盛强; 黄晓虹; 甘婷; 陈燕; 肖国宏

    2013-01-01

    Objective To investigate the mechanism of descended reproductive function induced by FMR1 gene knockout in male FMR1 gene knockout mice (KO) and male wild mice (WT).Methods The morphology of the testis of 10 weeks old KO and WT male mice were observed by HE staining.The mean optical density (MOD) of the expressions of neuropeptide Y (NPY) and gamma aminobutyricacid (GABA) in hypothalamus were tested and analyzed by immunohistochemistry and Image Pro Plus 6.0.Serum NPY concentrations were measured by ELISA.Results No obvious pathological differences in testis were found between KO and WT mice.The MOD of NPY in hypothalamus and the expression of NPY in serum in KO mice were weaken than those in WT mice,respectively [0.27 ± 0.031 vs.0.31 ± 0.031,P < 0.05; (179.21 ± 50.773)ng/L vs.(225.24 ± 52.293) ng/L,P <0.05].There was no significant difference in the MOD of GABA in hypothalamus between KO and WT mice (0.29 ±0.017 vs.0.28 ± 0.009,P > 0.05).Conclusions FMR1 gene may down-regulate the reproductive function of male mice through reducing the expression of NPY.%目的:利用FMR1基因敲除鼠(KO)和野生型FVB鼠(WT),研究FMR1基因敲除引起雄鼠生殖功能下降的可能机制.方法:随机取10周的KO及WT雄鼠,HE染色观察睾丸形态;免疫组化及Image ProPlus 6.0测定分析下丘脑神经肽Y(NPY)及γ-氨基丁酸(GABA)表达的平均光密度值;ELISA测定血清NPY水平.结果:KO、WT小鼠睾丸形态未见明显不同;KO雄鼠下丘脑NPY的表达弱于WT雄鼠(0.27±0.031,0.31±0.031,P<0.05);KO雄鼠血清NPY的表达弱于WT雄鼠(179.21±50.773,225.24±52.293,P< 0.05);两种基因型小鼠下丘脑GABA的表达差异无统计学意义(0.29±0.017,0.28±0.009,P> 0.05).结论:FMR1基因可能是通过下调NPY的表达来降低雄鼠生殖功能的.

  18. 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.

  19. Conditional Knockout Adam10 Gene of Neuronal Cell in Mouse Leads to Cortical Dysplasia%选择性敲除小鼠神经细胞 Adam10基因导致大脑皮质发育不良

    Institute of Scientific and Technical Information of China (English)

    王义辉; 李秀娟; 渠文生

    2015-01-01

    Objective: To investigate the role of Adam10 gene in mouse central nervous system (CNS) develop-ment. Methods: Gfapcre mice were mated to Adam10lox/lox mice using cre-loxp conditional gene knockout technique, and mice of conditional knockout Adam10 gene of neuronal cells(Gfapcre-Adam10lox/lox) were produced. At postnatal day of fourteen, mouse brain sections were prepared and HE staining was used to observe CNS development in Adam10 gene knockout mice. Results: By conditional knockout Adam10 gene of neuronal cell in mice (Gfapcre-Adam10lox/lox), mice could survive to about three weeks after birth. A tiny fraction of mice showed cortical defect,and developed cerebral cortex showed disorders of cortical lamination by HE staining. Conclusion: Adam10 gene plays an important role in CNS development. Conditional knockout Adam10 gene of neuronal cell in mouse leads to cortical defect or dysplasia.%目的:研究 Adam10基因在小鼠神经系统发育中的作用。方法:利用 Cre-loxp 转基因鼠技术,将 Gfapcre转基因鼠和 Adam10lox/lox 转基因鼠杂交,得到神经细胞特异性 Adam10基因敲除鼠(Gfapcre-Adam10lox/lox),在出生后第14天对大脑切片行 HE 染色,观察 Adam10基因敲除后神经系统发育情况。结果:选择性敲除小鼠神经细胞 Adam10基因(Gfapcre-Adam10lox/lox),小鼠可存活至出生后3周左右,部份小鼠大脑皮质单侧或双侧缺失,未出现皮质缺失的小鼠大脑皮质经 HE 染色提示出现层次结构紊乱。结论:Adam10基因在小鼠神经系统发育中具有重要作用,选择性敲除神经细胞 Adam10基因后导致小鼠大脑皮质缺失或层次结构紊乱。

  20. Vectors Building and Usage for Gene Knockout, Protein Expression and Fluorescent Fusion Protein in The Rice Blast Fungus%适用于稻瘟病菌基因敲除、过表达和荧光融合蛋白表达载体的构建和使用

    Institute of Scientific and Technical Information of China (English)

    李海娇; 卢建平; 刘小红; 张莉林; 林福呈

    2012-01-01

    This study is to supply a series of vectors for gene knockout, overexpression, and expressing fluorescent fusion proteins in the rice blast fungus. These vectors should be easily worked, time-saving, reliable, and conveniently for the research in the gene function of Magnaporthe oryzae. PCR, enzyme digestion, ligation a^id transformation were used to construct the plasmids. We cloned two promoters (SOD1 promoter and H3 promoter) which strongly expressed in the mycelia and conidia, built 3 vectors for knockout (pBS-SUR, pBS-BAS,pBS-NEO), 4 vectors for overexpression (pKD5, pKD6, pKD61 and pKD8), and 7 vectors for fluorescent fusion protein expression (pKD5-GFP, pKD5-RED, pKD6-GFP, pKD6-RED, pKD7-RED, pKD8-GFP and pKD8-RED) in M. Oryzae and other filamentous fungi. These plasmids could be introduced into the fungi via protoplast transformation, or A grobacterium tumefaciens -mediated transformation. The knockout mutants could be identified by PCR, Southern blot and Western blot, the fluorescence of the transformants was observed under the fluorescent microscope, and the expression level of genes in the transformants was assayed by Real-time PCR. We have used knockout constructs built by these knockout vectors (pBS-SUR, pBS-BAS, pBS-NEO) and pBS-HPHl together to knockout 4 genes simultaneously in M. Oryzae. After transforming pKD5-RED, pKD6-GFP or pKD6-RED into M. Oryzae via A grobacterium tumefac iens -mediated transformation, green or red fluorescent fusion proteins under the control of SOD1 or H3 promoter were expressed strongly in the hyphae; Real-time PCR results showed eGFP mRNA or DsRED2 mRNA level promoted by SOD1 promoter was 2.5 or 5.4 folds of (I-tubulin, and DsRED2 mRNA level promoted by H3 promoter was 20.8 folds of fi-tubulin in the mycelia. MoATG8-DsRED2 fusion protein produced by pKD6-RED could locate M0ATG8 exactly in the nearby of vacuoles. Observation on DsRED2 fluorescent protein under micrpscope showed that DsRED2 under control of SOD1 promoter

  1. Mice expressing the human CYP7A1 gene in the mouse CYP7A1 knock-out background lack induction of CYP7A1 expression by cholesterol feeding and have increased hypercholesterolemia when fed a high fat diet.

    Science.gov (United States)

    Chen, Jean Y; Levy-Wilson, Beatriz; Goodart, Sheryl; Cooper, Allen D

    2002-11-08

    Cholesterol 7alpha-hydroxylase (CYP7A1) catalyzes the rate-limiting step in the pathway responsible for the formation of the majority of bile acids. Transcription of the gene is regulated by the size of the bile acid pool and dietary and hormonal factors. The farnesoid X receptor and the liver X receptor (LXR) are responsible for regulation by bile acids and cholesterol, respectively. To study the effects of dietary cholesterol and fat upon expression of the human CYP7A1 gene, mice were generated by crossing transgenic mice carrying the human CYP7A1 gene with mice that were homozygous knock-outs (CYP7A1(-/-)). The mice (mCYP7A1(-/-)/hCYP7A1) expressed the human gene at much higher levels than did the transgenics bred in the wild-type background. A diet containing 1% cholic acid reduced the expression of the human gene in mCYP7A1(-/-)/hCYP7A1 mice to undetectable levels. Cholestyramine (5%) increased the level of expression of the human gene and the mouse gene. Thus, farnesoid X receptor-mediated regulation was preserved. A diet containing 2% cholesterol increased expression of the mouse gene in wild-type mice, but it did not affect expression of the human gene in mCYP7A1(-/-)/hCYP7A1 mice. None of the diets altered the serum cholesterol or triglyceride levels in these mice; 1% cholic acid caused a redistribution of cholesterol from the high density lipoprotein to the low density lipoprotein density in the humanized mice but not in wild-type mice. A diet containing 30% saturated fat and 2% cholesterol caused a decrease in CYP7A1 levels in mCYP7A1(-/-)/hCYP7A1 mice. The serum cholesterol levels rose in all mice fed this diet. The increase was greater in the mCYP7A1(-/-)/hCYP7A1 mice. Together, these data suggest that the lack of an LXR element in the region from -56 to -49 of the human CYP7A1 promoter may account for some of the differences in response to diets between humans and rodents.

  2. Metabolic flux analysis of Escherichia coli knockouts: lessons from the Keio collection and future outlook.

    Science.gov (United States)

    Long, Christopher P; Antoniewicz, Maciek R

    2014-08-01

    Cellular metabolic and regulatory systems are of fundamental interest to biologists and engineers. Incomplete understanding of these complex systems remains an obstacle to progress in biotechnology and metabolic engineering. An established method for obtaining new information on network structure, regulation and dynamics is to study the cellular system following a perturbation such as a genetic knockout. The Keio collection of all viable Escherichia coli single-gene knockouts is facilitating a systematic investigation of the regulation and metabolism of E. coli. Of all omics measurements available, the metabolic flux profile (the fluxome) provides the most direct and relevant representation of the cellular phenotype. Recent advances in (13)C-metabolic flux analysis are now permitting highly precise and accurate flux measurements for investigating cellular systems and guiding metabolic engineering efforts.

  3. Vergleichende Studie zur Expression von Neuropeptiden und von Calcium-bindenden Proteinen im Hippocampus von BDNF Knock-out Mäusen und den entsprechenden Wildtyp Geschwistertieren

    OpenAIRE

    Herrmann-Schwartzkopff, Katharina Helene

    2010-01-01

    Brain derived neurotrophic factor (BDNF) is well known for its positive effects on survival, development and differentiation of neurons in the central nervous system. It exerts its action through binding to its high (TrkB) and low (p75) affinity receptors. This work examines the expression of neuropeptides and calcium-binding proteins in the hippocampus of BDNF knockout mice (BDNF -/-) and their corresponding wild type littermates. With the use of highly specific antibodies the hippoca...

  4. Methylphenidate restores novel object recognition in DARPP-32 knockout mice.

    Science.gov (United States)

    Heyser, Charles J; McNaughton, Caitlyn H; Vishnevetsky, Donna; Fienberg, Allen A

    2013-09-15

    Previously, we have shown that Dopamine- and cAMP-regulated phosphoprotein of 32kDa (DARPP-32) knockout mice required significantly more trials to reach criterion than wild-type mice in an operant reversal-learning task. The present study was conducted to examine adult male and female DARPP-32 knockout mice and wild-type controls in a novel object recognition test. Wild-type and knockout mice exhibited comparable behavior during the initial exploration trials. As expected, wild-type mice exhibited preferential exploration of the novel object during the substitution test, demonstrating recognition memory. In contrast, knockout mice did not show preferential exploration of the novel object, instead exhibiting an increase in exploration of all objects during the test trial. Given that the removal of DARPP-32 is an intracellular manipulation, it seemed possible to pharmacologically restore some cellular activity and behavior by stimulating dopamine receptors. Therefore, a second experiment was conducted examining the effect of methylphenidate. The results show that methylphenidate increased horizontal activity in both wild-type and knockout mice, though this increase was blunted in knockout mice. Pretreatment with methylphenidate significantly impaired novel object recognition in wild-type mice. In contrast, pretreatment with methylphenidate restored the behavior of DARPP-32 knockout mice to that observed in wild-type mice given saline. These results provide additional evidence for a functional role of DARPP-32 in the mediation of processes underlying learning and memory. These results also indicate that the behavioral deficits in DARPP-32 knockout mice may be restored by the administration of methylphenidate.

  5. FMR1基因敲除对雄性小鼠生殖功能的影响%The influence of FMR1 gene knockout on the reproduction of male mice

    Institute of Scientific and Technical Information of China (English)

    祝亚桥; 周兴; 陈盛强

    2012-01-01

    Objective To investigate the influence of fragile x mental retardation-1 (FMR1) gene on the spermatogenesis and reproduction of male mice. Methods FMR1 knockout (KO) male mice and wild type (WT) male mice were mated with wt female mice. The number of litters, pregnancy rate and male mice having offsprings were counted. Serum T, FSH and LH concentrations were also measured. The density, mortality and morphology of the left cauda epididymis sperms were analyzed, HE staining was performed on the right side. Results The pregnance rate of wt female mice mated with FMR1K0 males was significantly lower than the control group (41.7% vs. 87. 5% , P 0.05). Male fertility showed that 41.7% of KO mice had pups, whereas 91.7% of the mice had pups in the control group (P 0.05).两组小鼠血清T,FSH,LH浓度无统计学差异.KO组的睾丸附睾病理切片与WT组比较未见明显异常,其精子活率及各种畸形率与WT小鼠比较均没有统计学差异(P>0.05).结论:可以推测FMR1基因对雄性生殖系统发育有一定的影响,Fmr1基因的缺失降低了雄性小鼠生育率,但对精子生成、畸形率等未见明显影响,其对雄性生殖系统影响机制还有待进一步的实验研究.

  6. Phenotype of the taurine transporter knockout mouse.

    Science.gov (United States)

    Warskulat, Ulrich; Heller-Stilb, Birgit; Oermann, Evelyn; Zilles, Karl; Haas, Helmut; Lang, Florian; Häussinger, Dieter

    2007-01-01

    This chapter reports present knowledge on the properties of mice with disrupted gene coding for the taurine transporter (taut-/- mice). Study of those mice unraveled some of the roles of taurine and its membrane transport for the development and maintenance of normal organ functions and morphology. When compared with wild-type controls, taut-/- mice have decreased taurine levels in skeletal and heart muscle by about 98%, in brain, kidney, plasma, and retina by 80 to 90%, and in liver by about 70%. taut-/- mice exhibit a lower body mass as well as a strongly reduced exercise capacity compared with taut+/- and wild-type mice. Furthermore, taut-/- mice show a variety of pathological features, for example, subtle derangement of renal osmoregulation, changes in neuroreceptor expression, and loss of long-term potentiation in the striatum, and they develop clinically relevant age-dependent disorders, for example, visual, auditory, and olfactory dysfunctions, unspecific hepatitis, and liver fibrosis. Taurine-deficient animal models such as acutely dietary-manipulated foxes and cats, pharmacologically induced taurine-deficient rats, and taurine transporter knockout mouse are powerful tools allowing identification of the mechanisms and complexities of diseases mediated by impaired taurine transport and taurine depletion (Chapman et al., 1993; Heller-Stilb et al., 2002; Huxtable, 1992; Lake, 1993; Moise et al., 1991; Novotny et al., 1991; Pion et al., 1987; Timbrell et al., 1995; Warskulat et al., 2004, 2006b). Taurine, which is the most abundant amino acid in many tissues, is normally found in intracellular concentrations of 10 to 70 mmol/kg in mammalian heart, brain, skeletal muscle, liver, and retina (Chapman et al., 1993; Green et al., 1991; Huxable, 1992; Timbrell et al., 1995). These high taurine levels are maintained by an ubiquitous expression of Na(+)-dependent taurine transporter (TAUT) in the plasma membrane (Burg, 1995; Kwon and Handler, 1995; Lang et al., 1998

  7. Disturbance of response to acute thermal pain in naturally occurring cholecystokinin-a receptor gene knockout Otsuka Long-Evans Tokushima Fatty (OLETF) rats.

    Science.gov (United States)

    Miyasaka, Kyoko; Nomoto, Shigeki; Ohta, Minoru; Kanai, Setsuko; Kaneko, Takao; Tahara, Shoichi; Funakoshi, Akihiro

    2006-08-01

    Otsuka Long-Evans Tokushima Fatty (OLETF) rats lack cholecystokinin-A receptor (CCK-AR) because of a genetic abnormality. We observed that body temperature homeostasis in response to changes in ambient temperature was deteriorated in OLETF rats, while the functions of the signal outputs from the hypothalamus to effectors were not impaired. Deteriorated homeostasis was also seen in CCK-AR deficient (-/-) mice. In the present study, we examined whether the sensory pathway involved in transmitting signals about temperature from the skin to the brain was impaired in OLETF rats. To elucidate the involvement of CCK-AR function, we conducted the same experiment in CCK-AR(-/-) mice. Responses to thermal pain were assessed using the Hargreaves' plantar test apparatus. Shortening of withdrawal latency was observed in OLETF rats compared to control rats, indicating thermal hyperalgesia. Behavioral responses following paw withdrawal were disturbed in OLETF rats. The 5-hydroxytryptamine (5-HT) and 5-hydroxyindole acetic acid contents in the hippocampus and frontal cortex of OLETF rats were significantly higher than in those of the controls. CCK-AR(-/-) mice did not show any differences from wild-type mice. In conclusion, OLETF rats showed thermal hyperalgesia and disturbed responses to thermal pain, and an alteration of 5-HT function might have a role in this disturbance.

  8. Role of Leishmania (Leishmania chagasi amastigote cysteine protease in intracellular parasite survival: studies by gene disruption and antisense mRNA inhibition

    Directory of Open Access Journals (Sweden)

    Kucknoor Ashwini S

    2005-02-01

    Full Text Available Abstract Background The parasitic protozoa belonging to Leishmania (L. donovani complex possess abundant, developmentally regulated cathepsin L-like cysteine proteases. Previously, we have reported the isolation of cysteine protease gene, Ldccys2 from Leishmania (L. chagasi. Here, we have further characterized this cysteine protease gene and demonstrated its role during infection and survival of Leishmania (L. chagasi within the U937 macrophage cells. Results The amastigote specific Ldccys2 genes of L. (L. chagasi and L. (L. donovani have identical gene organization, as determined by southern blots. In vivo expression analyses by Northern blots showed that Ldccys2 is amastigote specific. Western blot using anti-Ldccys2 antibody confirmed the amastigote specific protein expression. Recombinant expression of Ldccys2, a 30 kDA protein, was functionally active in a gelatin assay. Results from Ldccys2 heterozygous knockout mutants showed its role during macrophage infection and in intra-macrophage survival of the parasites. Since attempts to generate null mutants failed, we used antisense RNA inhibition to regulate Ldcccys2 gene expression. Not surprisingly, the results from antisense studies further confirmed the results from heterozygous knockout mutants, reiterating the importance of amastigote specific cysteine proteases in Leishmania infection and pathogenesis. Conclusions The study shows that Ldccys2 is a developmentally regulated gene and that Ldccys2 is expressed only in infectious amastigote stages of the parasite. The collective results from both the heterozygous knockout mutants and antisense mRNA inhibition studies shows that Ldccys2 helps in infection and survival of L. (L. chagasi amastigotes within the macrophage cells. Finally, antisense RNA technique can be used as an alternate approach to gene knockout, for silencing gene expression in L. (L. chagasi, especially in cases such as this, where a null mutant cannot be achieved by

  9. Universal statistics of the knockout tournament

    CERN Document Server

    Baek, Seung Ki; Park, Hye Jin; Kim, Beom Jun

    2014-01-01

    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.

  10. 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.

  11. Influence of different frequency impulse electromagnetic fields on osteoprotegerin gene knockout mice with osteoporosis%不同频率脉冲电磁场对骨保护素基因敲除小鼠骨质疏松影响

    Institute of Scientific and Technical Information of China (English)

    刘亚林; 魏丽; 贺晓晔; 张新玉

    2011-01-01

    Objective To study the optimal treatment frequency of pulsed electromagnetic fields for osteoporosis by intervening osteoprotegerin gene knockout osteoporosis mice with different frequency impulse electromagnetic fields.Methods Thirty osteoprotegerin knockout mice aged 8 weeks old were randomly divided into three groups, 10 each.Group A did not receive pulsed electromagnetic fields treatment.Group B received pulsed electromagnetic fields treatment at 8 Hz frequency with 4.0 mT intensity, 20 minutes daily, totally for 30 days.Group C received pulsed electromagnetic fields treatment at 32 Hz frequency with 4.0 mT intensity, 20 minutes daily, totally for 30 days.Each group was measured bone density by dual energy X-ray absorptiometry before and after treatment.Results After treatment, the bone density in group B and C was different from that in group A(P<0.05), and there was no significant difference between group B and group C(P>0.05).Conclusion The pulsed electromagnetic fields treatment is effective for osteoprotegerin gene knockout osteoporosis mice, and the frequencies from 8 Hz to 32 Hz can get the same therapeutic effect.%目的:采用不同频率的脉冲电磁场干预骨保护素基因敲除小鼠骨质疏松模型,探讨脉冲电磁场治疗骨质疏松的适宜频率.方法:8周龄雌雄各半骨保护素基因敲除小鼠30只,随机分为A,B,C组,每组各10只,A组为对照组,不进行干预;B组小鼠每天在强度为4 mT,频率为8 Hz的磁场中照射治疗20 min,共30 d;C组小鼠每天在强度为4mT,频率为32 Hz的磁场中照射治疗20 min,共30 d.各组小鼠在治疗前及治疗30 d后用双能X线检测骨密度值.结果:治疗后B,C组骨密度值与A组比较差异有统计学意义(P0.05).结论:脉冲电磁场对骨保护素基因敲除小鼠骨质疏松有治疗效果,频率为8~32 Hz的磁场治疗疗效相同.

  12. Gliosis after traumatic brain injury in conditional ephrinB2-knockout mice

    Institute of Scientific and Technical Information of China (English)

    LIU Ling; CHEN Xiao-lin; YANG Jian-kai; REN Ze-guang; WANG Shuo

    2012-01-01

    Background In response to the injury of the central nervous system (CNS),the astrocytes upregulate the expression of glial fibrillary acidic protein (GFAP),which largely contributes to the reactive gliosis after brain injury.The regulatory mechanism of this process is still not clear.In this study,we aimed to compare the ephrin-B2 deficient mice with the wild type ones with regard to gliosis after traumatic brain injury.Methods We generated ephrin-B2 knockout mice specifically in CNS astrocytes.Twelve mice from this gene-knockout strain were randomly selected along with twelve mice from the wild type littermates.In both groups,a modified controlled cortical impact injury model was applied to create a closed traumatic brain injury.Twenty-eight days after the injury,Nissl staining and GFAP immunofluorescence staining were used to compare the brain atrophy and GFAP immunoreactivity between the two groups.All the data were analyzed by t-test for between-group comparison.Results We successfully set up the conditional ephrin-B2 knockout mice strain,which was confirmed by genotyping and ephrin-B2/GFAP double staining.These mice developed normally without apparent abnormality in general appearance.Twenty-eight days following brain injury,histopathology revealed by immunohistochemistry showed different degrees of cerebral injuries in both groups.Compared with wild-type group,the ephrin-B2 knockout group exhibited less brain atrophy ratio for the injured hemispheres (P=0.005) and hippocampus (P=0.027).Also the wild-type group demonstrated greater GFAP immunoreactivity increment within hippocampal regions (P=0.008).Conclusions The establishment of conditional ephrin-B2 knockout mice provides us with a new way to explore the role of ephrin-B2 in astrocytes.Our findings revealed less atrophy and GFAP immunoreactivity in the knockout mice strain after traumatic brain injury,which implied ephrin-B2 could be one of the promoters to upregulate gliosis following brain injury.

  13. Empirical study of supervised gene screening

    Directory of Open Access Journals (Sweden)

    Ma Shuangge

    2006-12-01

    Full Text Available Abstract Background Microarray studies provide a way of linking variations of phenotypes with their genetic causations. Constructing predictive models using high dimensional microarray measurements usually consists of three steps: (1 unsupervised gene screening; (2 supervised gene screening; and (3 statistical model building. Supervised gene screening based on marginal gene ranking is commonly used to reduce the number of genes in the model building. Various simple statistics, such as t-statistic or signal to noise ratio, have been used to rank genes in the supervised screening. Despite of its extensive usage, statistical study of supervised gene screening remains scarce. Our study is partly motivated by the differences in gene discovery results caused by using different supervised gene screening methods. Results We investigate concordance and reproducibility of supervised gene screening based on eight commonly used marginal statistics. Concordance is assessed by the relative fractions of overlaps between top ranked genes screened using different marginal statistics. We propose a Bootstrap Reproducibility Index, which measures reproducibility of individual genes under the supervised screening. Empirical studies are based on four public microarray data. We consider the cases where the top 20%, 40% and 60% genes are screened. Conclusion From a gene discovery point of view, the effect of supervised gene screening based on different marginal statistics cannot be ignored. Empirical studies show that (1 genes passed different supervised screenings may be considerably different; (2 concordance may vary, depending on the underlying data structure and percentage of selected genes; (3 evaluated with the Bootstrap Reproducibility Index, genes passed supervised screenings are only moderately reproducible; and (4 concordance cannot be improved by supervised screening based on reproducibility.

  14. Establishment, identification and preliminary phenotype of mouse model of specific Smad4 conditional gene knockout in lens ectoderm%条件性 Sm ad4基因敲除鼠模型的建立和鉴定及初步表型

    Institute of Scientific and Technical Information of China (English)

    刘瑛; 林丁

    2014-01-01

    analysis by establishing the mouse model of specific Smad4 conditional gene knockout in ocular tissue by Cre/LoxP system of this kind of mouse model. METHODS: Mouse of specific Smad4 conditional knockout in lens ectoderm ( Le-Cre; Samd4fl/fl or also called mutant mouse) was obtained by mating the Pax6 promoter-driven Cre transgenic mouse ( Le-Cre ) with Smad4 wildtype mouse ( Smad4 fl/fl).To confirm that Smad4 has been conditionally inactivated only in the specific tissue of ectoderm such as lens, cornea and ectoderm of the eyelids so on.A series of assays were carried out to reveal the validity and specificity of Smad4 gene knockout at molecular and cellular levels, including genotyping by PCR, detection of green fluorescence protein ( GFP) in specific tissue and Smad4 protein.The expression of Le-Cre from Lacz staining using ROSA26 reporter genes in specific ocular tissue of mice can be visualized.Preliminary phenotype of mutant mouse was also observed. RESULTS: As early as around E10.0, strong GFP expression was observed in the embryonic lens and periorbital ectoderm of the mice, which showed Le-Cre was expressed in specific target tissue. Through genotyping for Smad4, Cre and Rosa genes, the mice were determined if they have carried Cre, Smad4 allele or Rosa reporter gene.It was further confirmed by lens-sampled genotyping that Smad4 gene was removed from some specific tissue such as lens.The spatial-temporal expression and tissue specificity of Le-Cre recombinase was also revealed by LacZ staining of Rosa; Le-Cre double transgenic mouse. According to Immunohistochemical staining, Smad4 was widely expressed in normal embryonic eyes, mainly appearing in the cytoplasm at the early embryonic stage and were transferred to nucleus with gestation developing, while in mutant embryonic eyes, Smad4 was void of expression in Cre-expressed tissues. It was observed that Smad4 mutant mouse could survive the conditional gene knockout.But those mice showed abnormal appearance such

  15. 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.

  16. Normal Maternal Behavior, But Increased Pup Mortality, in Conditional Oxytocin Receptor Knockout Females

    OpenAIRE

    Macbeth, Abbe H.; Stepp, Jennifer E.; Lee, Heon-Jin; Young, W. Scott; Caldwell, Heather K.

    2010-01-01

    Oxytocin (Oxt) and the Oxt receptor (Oxtr) are implicated in the onset of maternal behavior in a variety of species. Recently, we developed two Oxtr knockout lines: a total body knockout (Oxtr−/−) and a conditional Oxtr knockout (OxtrFB/FB) in which the Oxtr is lacking only in regions of the forebrain, allowing knockout females to potentially nurse and care for their biological offspring. In the current study, we assessed maternal behavior of postpartum OxtrFB/FB females toward their own pups...

  17. A STAT-1 Knockout Mouse Model for Machupo Virus Pathogenesis

    Science.gov (United States)

    2011-06-14

    antiviral therapeutics discovery. Because arenaviruses can block host IFN responses to establish infection, mice lacking elements of the interferon... arenaviruses (including MACV) binds to the retinoic acid-inducible gene I (RIG-I) protein and subsequently inhibits IFN-beta responses [19...although this mechanism has yet to be precisely described for arenaviruses [26]. Although it is probable that cytokine levels in STAT-1 knockout mice will

  18. NELF knockout is associated with impaired pubertal development and subfertility

    Science.gov (United States)

    Quaynor, Samuel D.; Ko, Eun Kyung; Chorich, Lynn P.; Sullivan, Megan E.; Demir, Durkadin; Waller, Jennifer L.; Kim, Hyung-Goo; Cameron, Richard S.; Layman, Lawrence C.

    2015-01-01

    Puberty and reproduction require proper signaling of the hypothalamic-pituitary-gonadal axis controlled by gonadotropin-releasing hormone (GnRH) neurons, which arise in the olfactory placode region and migrate along olfactory axons to the hypothalamus. Factors adversely affecting GnRH neuron specification, migration, and function lead to delayed puberty and infertility. Nasal embryonic luteinizing hormone-releasing factor (NELF) is a predominantly nuclear protein. NELF mutations have been demonstrated in patients with hypogonadotropic hypogonadism, but biallelic mutations are rare and heterozygous NELF mutations typically co-exist with mutations in another gene. Our previous studies in immortalized GnRH neurons supported a role for NELF in GnRH neuron migration. To better understand the physiology of NELF, a homozygous Nelf knockout (KO) mouse model was generated. Our findings indicate that female Nelf KO mice have delayed vaginal opening but no delay in time to first estrus, decreased uterine weight, and reduced GnRH neuron number. In contrast, male mice were normal at puberty. Both sexes of mice had impaired fertility manifested as reduced mean litter size. These data support that NELF has important reproductive functions. The milder than expected phenotype of KO mice also recapitulates the human phenotype since heterozygous NELF mutations usually require an additional mutation in a second gene to result in hypogonadotropic hypogonadism. PMID:25731822

  19. One-neutron knockout from Ne24-28 isotopes

    CERN Document Server

    Rodriguez-Tajes, C; Caamano, M; Faestermann, T; Cortina-Gil, D; Zhukov, M; Simon, H; Nilsson, T; Borge, M J G; Alvarez-Pol, H; Winkler, M; Prochazka, A; Nociforo, C; Weick, H; Kanungo, R; Perez-Loureiro, D; Kurtukian, T; Suemmerer, K; Eppinger, K; Perea, A; Chatillon, A; Maierbeck, P; Benlliure, J; Pascual-Izarra, C; Gernhaeuser, R; Geissel, H; Aumann, T; Kruecken, R; Larsson, K; Tengblad, O; Benjamim, E; Jonson, B; Casarejos, E

    2010-01-01

    One-neutron knockout reactions of Ne24-28 in a beryllium target have been studied in the Fragment Separator (FRS), at GSI. The results include inclusive one-neutron knockout cross-sections as well as longitudinal-momentum distributions of the knockout fragments. The ground-state structure of the neutron-rich neon isotopes was obtained from an analysis of the measured momentum distributions. The results indicate that the two heaviest isotopes, Ne-27 and Ne-28, are dominated by a configuration in which a s(1/2) neutron is coupled to an excited state of the Ne-26 and Ne-27 core, respectively. (C) 2010 Elsevier B.V. All rights reserved.

  20. Molecular Studies on Preproinsulin Gene

    Directory of Open Access Journals (Sweden)

    Sabir Sarah

    2016-01-01

    Full Text Available Insulin plays an important role in maintaining the blood glucose level of the body. The β-cells of pancreas produce insulin in the form of precursor that is preproinsulin. The gene of preproinsulin provides an interesting system for addressing question related to molecular evolution. Recombinant DNA technology has made it possible to isolate and sequence the chromosomal genes coding for unique protein products. Although preproinsulin of various organism has been isolated and cloned, but there is no report from buffalo (Bubalus bubalis that is our major livestock. The genomic DNA of buffalo was isolated using Laura-Lee-Boodram method. The part of preproinsulin gene (596bp and 520bp using BPPI-UPS and bpiful_F as forward and BC1-C as reverse primer was amplified. Cloning of amplified fragments of gene were performed in pCR 2.1 vector. Positive clones were screened on the basis of blue white selection. The band obtained on 596bp and 520bp after colony PCR confirmed the successful cloning of preproinsulin gene in pCR 2.1 vector.

  1. Bioinformatics study of the mangrove actin genes

    Science.gov (United States)

    Basyuni, M.; Wasilah, M.; Sumardi

    2017-01-01

    This study describes the bioinformatics methods to analyze eight actin genes from mangrove plants on DDBJ/EMBL/GenBank as well as predicted the structure, composition, subcellular localization, similarity, and phylogenetic. The physical and chemical properties of eight mangroves showed variation among the genes. The percentage of the secondary structure of eight mangrove actin genes followed the order of a helix > random coil > extended chain structure for BgActl, KcActl, RsActl, and A. corniculatum Act. In contrast to this observation, the remaining actin genes were random coil > extended chain structure > a helix. This study, therefore, shown the prediction of secondary structure was performed for necessary structural information. The values of chloroplast or signal peptide or mitochondrial target were too small, indicated that no chloroplast or mitochondrial transit peptide or signal peptide of secretion pathway in mangrove actin genes. These results suggested the importance of understanding the diversity and functional of properties of the different amino acids in mangrove actin genes. To clarify the relationship among the mangrove actin gene, a phylogenetic tree was constructed. Three groups of mangrove actin genes were formed, the first group contains B. gymnorrhiza BgAct and R. stylosa RsActl. The second cluster which consists of 5 actin genes the largest group, and the last branch consist of one gene, B. sexagula Act. The present study, therefore, supported the previous results that plant actin genes form distinct clusters in the tree.

  2. Using engineered endonucleases to create knockout and knockin zebrafish models.

    Science.gov (United States)

    Bedell, Victoria M; Ekker, Stephen C

    2015-01-01

    Over the last few years, the technology to create targeted knockout and knockin zebrafish animals has exploded. We have gained the ability to create targeted knockouts through the use of zinc finger nucleases (ZFNs), transcription activator-like effector nucleases (TALENs) and clustered regularly interspaced short palindromic repeats/CRISPR associated system (CRISPR/Cas). Furthermore, using the high-efficiency TALEN system, we were able to create knockin zebrafish using a single-stranded DNA (ssDNA) protocol described here. Through the use of these technologies, the zebrafish has become a valuable vertebrate model and an excellent bridge between the invertebrate and mammalian model systems for the study of human disease.

  3. A control study to evaluate a computer-based microarray experiment design recommendation system for gene-regulation pathways discovery.

    Science.gov (United States)

    Yoo, Changwon; Cooper, Gregory F; Schmidt, Martin

    2006-04-01

    The main topic of this paper is evaluating a system that uses the expected value of experimentation for discovering causal pathways in gene expression data. By experimentation we mean both interventions (e.g., a gene knock-out experiment) and observations (e.g., passively observing the expression level of a "wild-type" gene). We introduce a system called GEEVE (causal discovery in Gene Expression data using Expected Value of Experimentation), which implements expected value of experimentation in discovering causal pathways using gene expression data. GEEVE provides the following assistance, which is intended to help biologists in their quest to discover gene-regulation pathways: Recommending which experiments to perform (with a focus on "knock-out" experiments) using an expected value of experimentation (EVE) method. Recommending the number of measurements (observational and experimental) to include in the experimental design, again using an EVE method. Providing a Bayesian analysis that combines prior knowledge with the results of recent microarray experimental results to derive posterior probabilities of gene regulation relationships. In recommending which experiments to perform (and how many times to repeat them) the EVE approach considers the biologist's preferences for which genes to focus the discovery process. Also, since exact EVE calculations are exponential in time, GEEVE incorporates approximation methods. GEEVE is able to combine data from knock-out experiments with data from wild-type experiments to suggest additional experiments to perform and then to analyze the results of those microarray experimental results. It models the possibility that unmeasured (latent) variables may be responsible for some of the statistical associations among the expression levels of the genes under study. To evaluate the GEEVE system, we used a gene expression simulator to generate data from specified models of gene regulation. Using the simulator, we evaluated the GEEVE

  4. Gene expression studies using microarrays

    NARCIS (Netherlands)

    Burgess, Janette

    2001-01-01

    1. The rapid progression of the collaborative sequencing programmes that are unravelling the complete genome sequences of many organisms are opening pathways for new approaches to gene analysis. As the sequence data become available, the bottleneck in biological research will shift to understanding

  5. Effects of Eaf2 gene knockout on cataract induced by ultraviolet irradiation in mice%Eaf2基因敲除对紫外线诱导的鼠白内障形成的影响

    Institute of Scientific and Technical Information of China (English)

    姜艳华; 张劲松

    2016-01-01

    目的:分析Eaf2基因敲除对紫外线诱导的小鼠白内障形成的影响。方法:将15只野生型( WT)小鼠作为对照组,10只Eaf2基因敲除( Eaf2 KO)小鼠作为实验组。两组均取14周龄左右的小鼠作为研究对象。进一步分组为:WT-nonUV、WT-UV、Eaf2 KO-nonUV、Eaf2 KO-UV,共4组。使用裂隙灯显微镜观察小鼠白内障程度,利用晶状体混浊分类系统Ⅱ( LOCSⅡ)对小鼠白内障进行分级。然后断颈处死小鼠,摘取晶状体进行暗视野显微镜照相,利用Image J软件对晶状体混浊程度进行分析,并将各测量结果进行统计学处理。结果:裂隙灯显微镜和暗视野显微镜的结果一致:WT-UV组及 Eaf2 KO-UV 组晶状体混浊程度明显高于 WT-nonUV组及Eaf2 KO-nonUV组,其中WT-UV组明显高于Eaf2 KO-UV组,均具有统计学差异(P<0.05)。结论:紫外线辐射能够导致小鼠白内障的形成,Eaf2蛋白质具有促进紫外线所致的小鼠白内障形成的作用。%Abstract•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

  6. 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.

  7. Brain response to traumatic brain injury in wild-type and interleukin-6 knockout mice: a microarray analysis.

    Science.gov (United States)

    Poulsen, Christian Bjørn; Penkowa, Milena; Borup, Rehannah; Nielsen, Finn Cilius; Cáceres, Mario; Quintana, Albert; Molinero, Amalia; Carrasco, Javier; Giralt, Mercedes; Hidalgo, Juan

    2005-01-01

    Traumatic injury to the brain is one of the leading causes of injury-related death or disability. Brain response to injury is orchestrated by cytokines, such as interleukin (IL)-6, but the full repertoire of responses involved is not well known. We here report the results obtained with microarrays in wild-type and IL-6 knockout mice subjected to a cryolesion of the somatosensorial cortex and killed at 0, 1, 4, 8 and 16 days post-lesion. Overall gene expression was analyzed by using Affymetrix genechips/oligonucleotide arrays with approximately 12,400 probe sets corresponding to approximately 10,000 different murine genes (MG_U74Av2). A robust, conventional statistical method (two-way anova) was employed to select the genes significantly affected. An orderly pattern of gene responses was clearly detected, with genes being up- or down-regulated at specific timings consistent with the processes involved in the initial tissue injury and later regeneration of the parenchyma. IL-6 deficiency showed a dramatic effect in the expression of many genes, especially in the 1 day post-lesion timing, which presumably underlies the poor capacity of IL-6 knockout mice to cope with brain damage. The results highlight the importance of IL-6 controlling the response of the brain to injury as well as the suitability of microarrays for identifying specific targets worthy of further study.

  8. Mice lacking pituitary tumor transforming gene show elevated exposure of DGalNAc carbohydrate determinants

    Directory of Open Access Journals (Sweden)

    Lutsyk A. D.

    2012-04-01

    Full Text Available Aim. To investigate the influence of pituitary tumor transforming gene (pttg-1 knockout on glycome of parenchimal organs by means of lectin histochemistry. Methods. DGalNAc, DGlcNAc, NeuNAc carbohydrate determinants were labelled with soybean agglutinin (SBA and wheat germ agglutinin (WGA, conjugated to peroxidase, with subsequent visualization of the lectin-binding sites with diaminobenzidine. The testes and kidneys of murine strain BL6/C57 with the pttg-1 gene knockout (PTTG-KO were compared to the wild type (PTTG-WT animals, both groups 1 month of age. Results. Knockout of the pttg-1 gene was accompanied by enhanced exposure of the DGalNAc sugar residues within the Golgi complex of secondary spermatocytes, in a brush border of renal tubules and on the lumenal surface of collecting ducts. Conclusions. This study suggests that knockout of the pttg-1 gene may lead to the changes in carbohydrate processing in mammalian organism.

  9. Pax-8基因敲除小鼠心脏中NR4A1基因表达上调%Up-regulation of NR4A1 gene expression in Pax-8 gene knockout mice myocardium

    Institute of Scientific and Technical Information of China (English)

    黄晓燕; 高瞻; 周希; 梁万前; 陈锡文; 陈通克; 杨德业

    2011-01-01

    Objective: To find the possible genic pathway for the anti-apoptosis function of the ventricular septal defeet related to Pax-8. Method: The total RNA derived from the heart of Pax-8 KO-/- and Pax-8 KO+/- mice was extracted. Mouse genome DNA microarray was used to detect the differential expression level between the Pax-8 KO-/- and the Pax-8 KO+/- mice heart. The candidate genes were confirmed by RT-PCR and real time RT-PCR assay. Results: Microarray results showed that 25 genes were down-regulated and 17 were up-regulated in the Pax-8 KO-/- mice compared to the Pax-8 KO+/- mice. Nuclear receptor subfamily 4, group A, member 1 (NR4A1)was proved to be up-regulated by RT-PCR in the Pax-8 KO-/- mice heart. Real time RTPCR results revealed that NR4A1 in the Pax-8 KO-/- mice was 1.53 and 4.79 fold as much as in the Pax-8 KO+/- and the Pax-8+/+ mice (P<0.01). Conclusion: The NR4A1 gene is one of the downstream genes of the Pax-8 and probably evolved and played an important role in the mechanism of ventricular septum defect.%目的:寻找先天性心脏病室间隔缺损相关基因--转录因子Pax-8保护细胞凋亡的途径.方法:提取Pax-8基因敲除小鼠纯合子(Pax-8 KO-/-)和杂合子(Pax-8 KO+/-)的心脏总RNA,利用小鼠基因的基因芯片检测两组小鼠基因表达水平,找出差异表达的基因,并经半定量RT-PCR和荧光实时定量PCR技术初步筛选出转录因子Pax-8的下游基因.结果:基因芯片检测发现,与Pax-8 KO+/-组相比,在Pax-8 KO-/-小鼠中有25个基因表达下调,17个基因表达上调.用半定量RT-PCR验证发现,nuclear receptor sub-family4,group A,member 1(NR4A1)基因在Pax-8 KO-/-组上调.定量RT-PCR亦证实在Pax-8 KO-/-组NR4A1基因的表达水平较Pax-8 KO+/-组及Pax-8+/+(野生型)组分别上调1.53倍和4.79倍(P<0.01).结论:NR4A1基因受Pax-8基因调控,在Pax-8保护细胞凋亡途径中发挥作用.

  10. 应用 TALEN 技术敲除 gata4基因建立斑马鱼先天性心脏病模型%Knockout gata4 gene and establish ment of a zebrafish model of congenital heart disease by TALEN

    Institute of Scientific and Technical Information of China (English)

    刘静; 何嘉玲; 暴国; 李楠; 王天奇; 张长勇; 孙德明

    2015-01-01

    Objective To establish a gata4 gene knockout zebrafish model of congenital heart disease, and construct transcription activator-like effector nuclease ( TALEN) vectors targeting gata4 gene.Method We construct TALEN vectors targeting zabrafish gata4 gene using unit assembly method and the in vitro-transcribed TALEN mRNAs were microinjected into one-cell stage zebrafish embryos.The efficiency of TALEN was identified by injected embryos, and mutations of zebrafish were screened and confirmed the different types through PCR and enzyme digestion.Results We successfully constructed correct targeting vectors by enzyme digestion and sequencing, and the gene knockout efficiency was 35.18%.We screened the mutant zebrafish and confirmed different types of gata4 gene mutations.Conclusions A gata4 knockout zebrafish model is successfully established, it can provide a good animal model for further research of congenital heart diseases.%目的:人工构建TALEN靶向敲除载体敲除gata4基因,建立斑马鱼先天性心脏病动物模型。方法采用单元组装法构建靶向敲除gata4基因的载体,将其体外转录成TALEN mRNAs,通过显微注射的方式注入单细胞期受精卵中,胚胎检测TALEN的敲除效率,再通过剪尾、酶切、测序筛选发生基因突变的斑马鱼及突变的类型。结果酶切、测序结果证实成功构建出正确的 gata4靶向敲除载体,注入斑马鱼受精卵中,发生基因敲除的效率为35.18%,通过剪尾、PCR、酶切检测成功地筛选出了发生基因突变的斑马鱼,测序结果显示出不同种类的gata4基因突变。结论成功构建gata4基因敲除的斑马鱼动物模型,为进一步研究人类gata4基因突变引起先天性心脏病的发病机制提供了良好的动物模型。

  11. Advanced studies on human gene ZNF322

    Institute of Scientific and Technical Information of China (English)

    LI Yongqing; WANG Yuequn; YUAN Wuzhou; DENG Yun; ZHU Chuanbing; WU Xiushan

    2007-01-01

    The human novel gene of ZNF322 is cloned from human fetal eDNA library using the primers on the basis of the ZNF322 sequence analyzed with computer.The gene is located on Chromosome 6p22.1,and encodes a protein consisting of 402 amino acid residues and containing nine tandem C2H2-type zinc-finger motifs.Northern blot result shows that the gene is expressed in all examined adult tissues.Subcellular location study indicates that ZNF322-EGFP fusion protein is distributed in the nucleus and cytoplasm.Reporter gene assays show that ZNF322 is a potential transcriptional activator.

  12. Spinal 5-HT7 receptors are critical for alternating activity during locomotion: in vitro neonatal and in vivo adult studies using 5-HT7 receptor knockout mice.

    Science.gov (United States)

    Liu, Jun; Akay, Turgay; Hedlund, Peter B; Pearson, Keir G; Jordan, Larry M

    2009-07-01

    5-HT7 receptors have been implicated in the control of locomotion. Here we use 5-HT7 receptor knockout mice to rigorously test whether 5-HT acts at the 5-HT7 receptor to control locomotor-like activity in the neonatal mouse spinal cord in vitro and voluntary locomotion in adult mice. We found that 5-HT applied onto in vitro spinal cords of 5-HT7+/+ mice produced locomotor-like activity that was disrupted and subsequently blocked by the 5-HT7 receptor antagonist SB-269970. In spinal cords isolated from 5-HT7-/- mice, 5-HT produced either uncoordinated rhythmic activity or resulted in synchronous discharges of the ventral roots. SB-269970 had no effect on 5-HT-induced rhythmic activity in the 5-HT7-/- mice. In adult in vivo experiments, SB-269970 applied directly to the spinal cord consistently disrupted locomotion and produced prolonged-extension of the hindlimbs in 5-HT7+/+ but not 5-HT7-/- mice. Disrupted EMG activity produced by SB-269970 in vivo was similar to the uncoordinated rhythmic activity produced by the drug in vitro. Moreover, 5-HT7-/- mice displayed greater maximal extension at the hip and ankle joints than 5-HT7+/+ animals during voluntary locomotion. These results suggest that spinal 5-HT7 receptors are required for the production and coordination of 5-HT-induced locomotor-like activity in the neonatal mouse and are important for the coordination of voluntary locomotion in adult mice. We conclude that spinal 5-HT7 receptors are critical for alternating activity during locomotion.

  13. Brain activation by short-term nicotine exposure in anesthetized wild-type and beta2-nicotinic receptors knockout mice: a BOLD fMRI study

    Energy Technology Data Exchange (ETDEWEB)

    Suarez, S.V.; Changeux, J.P.; Granon, S. [Unite de Neurobiologie Integrative du Systeme Cholinergique, URA CNRS 2182, Institut Pasteur, Departement de Neuroscience, 25 rue du Dr Roux, 75015 Paris (France); Amadon, A.; Giacomini, E.; Le Bihan, D. [Service Hospitalier Frederic Joliot, 4 place du general Leclerc, 91400 Orsay (France); Wiklund, A. [Section of Anaesthesiology and Intensive Care Medicine, Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm (Sweden)

    2009-07-01

    Rationale: The behavioral effects of nicotine and the role of the beta2-containing nicotinic receptors in these behaviors are well documented. However, the behaviors altered by nicotine rely on the functioning on multiple brain circuits where the high-affinity {beta}2-containing nicotinic receptors ({beta}2*nAChRs) are located. Objectives We intend to see which brain circuits are activated when nicotine is given in animals naive for nicotine and whether the {beta}2*nAChRs are needed for its activation of the blood oxygen level dependent (BOLD) signal in all brain areas. Materials and methods: We used functional magnetic resonance imaging (fMRI) to measure the brain activation evoked by nicotine (1 mg/kg delivered at a slow rate for 45 min) in anesthetized C57BL/6J mice and {beta}2 knockout (KO) mice. Results: Acute nicotine injection results in a significant increased activation in anterior frontal, motor, and somatosensory cortices and in the ventral tegmental area and the substantia nigra. Anesthetized mice receiving no nicotine injection exhibited a major decreased activation in all cortical and subcortical structures, likely due to prolonged anesthesia. At a global level, {beta}2 KO mice were not rescued from the globally declining BOLD signal. However, nicotine still activated regions of a meso-cortico-limbic circuit likely via {alpha}7 nicotinic receptors. Conclusions: Acute nicotine exposure compensates for the drop in brain activation due to anesthesia through the meso-cortico-limbic network via the action of nicotine on {beta}2*nAChRs. The developed fMRI method is suitable for comparing responses in wild-type and mutant mice. (authors)

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

    Science.gov (United States)

    Nelson, Nicole C.

    2015-01-01

    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. PMID:26090739

  15. 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.

  16. Efficient CRISPR-rAAV engineering of endogenous genes to study protein function by allele-specific RNAi.

    Science.gov (United States)

    Kaulich, Manuel; Lee, Yeon J; Lönn, Peter; Springer, Aaron D; Meade, Bryan R; Dowdy, Steven F

    2015-04-20

    Gene knockout strategies, RNAi and rescue experiments are all employed to study mammalian gene function. However, the disadvantages of these approaches include: loss of function adaptation, reduced viability and gene overexpression that rarely matches endogenous levels. Here, we developed an endogenous gene knockdown/rescue strategy that combines RNAi selectivity with a highly efficient CRISPR directed recombinant Adeno-Associated Virus (rAAV) mediated gene targeting approach to introduce allele-specific mutations plus an allele-selective siRNA Sensitive (siSN) site that allows for studying gene mutations while maintaining endogenous expression and regulation of the gene of interest. CRISPR/Cas9 plus rAAV targeted gene-replacement and introduction of allele-specific RNAi sensitivity mutations in the CDK2 and CDK1 genes resulted in a >85% site-specific recombination of Neo-resistant clones versus ∼8% for rAAV alone. RNAi knockdown of wild type (WT) Cdk2 with siWT in heterozygotic knockin cells resulted in the mutant Cdk2 phenotype cell cycle arrest, whereas allele specific knockdown of mutant CDK2 with siSN resulted in a wild type phenotype. Together, these observations demonstrate the ability of CRISPR plus rAAV to efficiently recombine a genomic locus and tag it with a selective siRNA sequence that allows for allele-selective phenotypic assays of the gene of interest while it remains expressed and regulated under endogenous control mechanisms.

  17. Generation and behavior characterization of CaMKIIβ knockout mice.

    Directory of Open Access Journals (Sweden)

    Adam D Bachstetter

    Full Text Available The calcium/calmodulin-dependent protein kinase II (CaMKII is abundant in the brain, where it makes important contributions to synaptic organization and homeostasis, including playing an essential role in synaptic plasticity and memory. Four genes encode isoforms of CaMKII (α, β, δ, γ, with CaMKIIα and CaMKIIβ highly expressed in the brain. Decades of molecular and cellular research, as well as the use of a large number of CaMKIIα mutant mouse lines, have provided insight into the pivotal roles of CaMKIIα in brain plasticity and cognition. However, less is known about the CaMKIIβ isoform. We report the development and extensive behavioral and phenotypic characterization of a CaMKIIβ knockout (KO mouse. The CaMKIIβ KO mouse was found to be smaller at weaning, with an altered body mass composition. The CaMKIIβ KO mouse showed ataxia, impaired forelimb grip strength, and deficits in the rotorod, balance beam and running wheel tasks. Interestingly, the CaMKIIβ KO mouse exhibited reduced anxiety in the elevated plus maze and open field tests. The CaMKIIβ KO mouse also showed cognitive impairment in the novel object recognition task. Our results provide a comprehensive behavioral characterization of mice deficient in the β isoform of CaMKII. The neurologic phenotypes and the construction of the genotype suggest the utility of this KO mouse strain for future studies of CaMKIIβ in brain structure, function and development.

  18. Computerized video time lapse study of cell cycle delay and arrest, mitotic catastrophe, apoptosis and clonogenic survival in irradiated 14-3-3sigma and CDKN1A (p21) knockout cell lines.

    Science.gov (United States)

    Chu, Kenneth; Teele, Noella; Dewey, Michael W; Albright, Norman; Dewey, William C

    2004-09-01

    Computerized video time lapse (CVTL) microscopy was used to observe cellular events induced by ionizing radiation (10-12 Gy) in nonclonogenic cells of the wild-type HCT116 colorectal carcinoma cell line and its three isogenic derivative lines in which p21 (CDKN1A), 14-3-3sigma or both checkpoint genes (double-knockout) had been knocked out. Cells that fused after mitosis or failed to complete mitosis were classified together as cells that underwent mitotic catastrophe. Seventeen percent of the wild-type cells and 34-47% of the knockout cells underwent mitotic catastrophe to enter generation 1 with a 4N content of DNA, i.e., the same DNA content as irradiated cells arrested in G(2) at the end of generation 0. Radiation caused a transient division delay in generation 0 before the cells divided or underwent mitotic catastrophe. Compared with the division delay for wild-type cells that express CDKN1A and 14-3-3sigma, knocking out CDKN1A reduced the delay the most for cells irradiated in G(1) (from approximately 15 h to approximately 3- 5 h), while knocking out 14-3-3sigma reduced the delay the most for cells irradiated in late S and G(2) (from approximately 18 h to approximately 3-4 h). However, 27% of wild-type cells and 17% of 14-3-3sigma(-/-) cells were arrested at 96 h in generation 0 compared with less than 1% for CDKN1A(-/-) and double-knockout cells. Thus expression of CDKN1A is necessary for the prolonged delay or arrest in generation 0. Furthermore, CDKN1A plays a crucial role in generation 1, greatly inhibiting progression into subsequent generations of both diploid cells and polyploid cells produced by mitotic catastrophe. Thus, in CDKN1A-deficient cell lines, a series of mitotic catastrophe events occurred to produce highly polyploid progeny during generations 3 and 4. Most importantly, the polyploid progeny produced by mitotic catastrophe events did not die sooner than the progeny of dividing cells. Death was identified as loss of cell movement, i

  19. Establishment of Immortalized Mouse Bmp2 Knock-Out Dental Papilla Mesenchymal Cells Necessary for Study of Odontoblastic Differentiation and Odontogenesis

    Science.gov (United States)

    Wu, Lian; Wang, Feng; Donly, Kevin J.; Wan, Chunyan; Luo, Daoshu; Harris, Stephen E.; Macdougall, Mary; Chen, Shuo

    2016-01-01

    Bmp2 is essential for dentin formation. Bmp2 cKO mice exhibited similar phenotype to dentinogenesis imperfecta, showing dental pulp exposure, hypomineralized dentin, and delayed odontoblast differentiation. As it is relatively difficult to obtain lot of primary Bmp2 cKO dental papilla mesenchymal cells and to maintain a long-term culture of these primary cells, availability of immortalized deleted Bmp2 dental papilla mesenchymal cells is critical for studying the underlying mechanism of Bmp2 signal in odontogenesis. In this study, our goal was to generate an immortalized deleted Bmp2 dental papilla mesenchymal (iBmp2ko/ko dp) cell line by introducing Cre fluorescent protein (GFP) into the immortalized mouse floxed Bmp2 dental papilla mesenchymal (iBmp2fx/fx dp) cells. iBmp2ko/ko dp cells were confirmed by GFP and PCR. The deleted Bmp2 cells exhibited slow cell proliferation rate and cell growth was arrested in G2 phase. Expression of tooth-related marker genes and cell differentiation were decreased in the deleted cells. Importantly, extracellular matrix remodeling was impaired in the iBmp2ko/ko dp cells as reflected by the decreased Mmp-9 expression. In addition, with exogenous Bmp2 induction, these cell differentiation and mineralization were rescued as well as extracellular matrix remodeling was enhanced. Therefore, we for the first time described establishment of iBmpko/ko cells that are useful for study of mechanisms in regulating dental papilla mesenchymal cell lineages. PMID:26037045

  20. Establishment of Immortalized Mouse Bmp2 Knock-Out Dental Papilla Mesenchymal Cells Necessary for Study of Odontoblastic Differentiation and Odontogenesis.

    Science.gov (United States)

    Wu, Lian; Wang, Feng; Donly, Kevin J; Wan, Chunyan; Luo, Daoshu; Harris, Stephen E; MacDougall, Mary; Chen, Shuo

    2015-11-01

    Bmp2 is essential for dentin formation. Bmp2 cKO mice exhibited similar phenotype to dentinogenesis imperfecta, showing dental pulp exposure, hypomineralized dentin, and delayed odontoblast differentiation. As it is relatively difficult to obtain lot of primary Bmp2 cKO dental papilla mesenchymal cells and to maintain a long-term culture of these primary cells, availability of immortalized deleted Bmp2 dental papilla mesenchymal cells is critical for studying the underlying mechanism of Bmp2 signal in odontogenesis. In this study, our goal was to generate an immortalized deleted Bmp2 dental papilla mesenchymal (iBmp2(ko/ko)dp) cell line by introducing Cre recombinase and green fluorescent protein (GFP) into the immortalized mouse floxed Bmp2 dental papilla mesenchymal (iBmp2(fx/fx)dp) cells. iBmp2(ko/ko)dp cells were confirmed by GFP and PCR. The deleted Bmp2 cells exhibited slow cell proliferation rate and cell growth was arrested in G2 phase. Expression of tooth-related marker genes and cell differentiation were decreased in the deleted cells. Importantly, extracellular matrix remodeling was impaired in the iBmp2(ko/ko)dp cells as reflected by the decreased Mmp-9 expression. In addition, with exogenous Bmp2 induction, these cell differentiation and mineralization were rescued as well as extracellular matrix remodeling was enhanced. Therefore, we for the first time described establishment of iBmp(ko/ko) cells that are useful for study of mechanisms in regulating dental papilla mesenchymal cell lineages. © 2015 Wiley Periodicals, Inc.

  1. Simulation study on control of spill structure of slow extracted beam from a medical synchrotron with feed-forward and feedback using a fast quadruple magnet and RF-knockout system

    Science.gov (United States)

    Muraoka, Ryo; Nakanishi, Tetsuya

    2017-02-01

    A feedback control of the spill structure for the slow beam extraction from the medical synchrotron using a fast quadruple and radio frequency (RF)-knockout (QAR method) is studied to obtain the designed spill structure. In addition the feed-forward control is used so that the feedback control is performed effectively. In this extraction method, the spill of several ms are extracted continuously with an interval time of less than 1 ms. Beam simulation showed that a flat spill structure was effectively obtained with feed-forward and feedback control system as well as a step-wise structure which is useful for the shortening of an irradiation time in a spot scanning operation. The effect of current ripples from main quadruple magnet's power supplies could be also reduced with the feedback control application.

  2. Muscle developmental defects in heterogeneous nuclear Ribonucleoprotein A1 knockout mice

    Science.gov (United States)

    Liu, Ting-Yuan; Chen, Yu-Chia; Jong, Yuh-Jyh; Tsai, Huai-Jen; Lee, Chien-Chin; Chang, Ya-Sian; Chang, Jan-Gowth

    2017-01-01

    Heterogeneous ribonucleoprotein A1 (hnRNP A1) is crucial for regulating alternative splicing. Its integrated function within an organism has not, however, been identified. We generated hnRNP A1 knockout mice to study the role of hnRNP A1 in vivo. The knockout mice, hnRNP A1−/−, showed embryonic lethality because of muscle developmental defects. The blood pressure and heart rate of the heterozygous mice were higher than those of the wild-type mice, indicating heart function defects. We performed mouse exon arrays to study the muscle development mechanism. The processes regulated by hnRNP A1 included cell adhesion and muscle contraction. The expression levels of muscle development-related genes in hnRNP A1+/− mice were significantly different from those in wild-type mice, as detected using qRT-PCR. We further confirmed the alternative splicing patterns of muscle development-related genes including mef2c, lrrfip1, usp28 and abcc9. Alternative mRNA isoforms of these genes were increased in hnRNP A1+/− mice compared with wild-type mice. Furthermore, we revealed that the functionally similar hnRNP A2/B1 did not compensate for the expression of hnRNP A1 in organisms. In summary, our study demonstrated that hnRNP A1 plays a critical and irreplaceable role in embryonic muscle development by regulating the expression and alternative splicing of muscle-related genes. PMID:28077597

  3. FoxO3a基因缺失致小鼠脾脏进行性慢性炎性反应的观察%Progressive chronic inflammatory reaction in spleens of FoxO3a gene knockout mice

    Institute of Scientific and Technical Information of China (English)

    邱红; 陈晨; 王若立; 罗红; 赵宝霞

    2012-01-01

    目的 观察FoxO3a基因缺失致小鼠脾脏进行性慢性炎性反应.方法 分别于16周、24周和12个月称取FoxO3a基因敲除小鼠和对照小鼠体重;于16、24和38周处死各组小鼠,取脾脏,肉眼观察脾脏变化,并制备脾细胞悬液,进行细胞计数,同时取各组小鼠卵巢、肺及皮下等组织,观察其炎性变化.流式细胞术检测24周的FoxO3a基因敲除小鼠和对照小鼠脾细胞中T、B淋巴细胞和Mac-1+细胞数量及百分率;Real-time PCR检测脾细胞中炎性细胞因子S100A8和S100A9基因mRNA的表达水平.结果 与对照小鼠相比,FoxO3a基因敲除小鼠脾脏明显肥大,且随年龄增加更加显著,卵巢、肺及皮下等组织内可见大量炎性细胞浸润,脾细胞数明显升高;基因敲除组老年小鼠的体重明显低于对照小鼠;FoxO3a基因敲除小鼠的脾细胞中T、B淋巴细胞数增加明显,但所占脾细胞的百分率无明显增加,Mac-1+细胞数和百分率均明显增加;S100A8和S100A9基因mRNA的表达水平明显高于对照小鼠.结论 FoxO3a基因缺失致小鼠脾脏进行性慢性炎性反应.%Objective To observe the progressive chronic inflammatory reaction induced by Fox03a gene knockout in mice. Methods The bodyweights of Fox03a gene knockout and normal control mice were weighed at ages of 16 weeks, 24 weeks and 12 months separately. Partial mice in the two groups were killed at ages of 16, 24 and 38 weeks respectively, of which the spleens were collected, observed visually, prepared into splenocytes and counted. Meanwhile, the inflammatory reactions in various tissues including ovary, lung and subcutaneous tissues were observed. The counts and percentages of T and B lymphocytes and Mac-1+ cells in spleens of FoxO3a gene knockout and control mice at age of 24 weeks were determined by flow cytometry, while the expression levels of S100A8 and S100A9 mRNAs in splenocytes by real-time PCR. Results Compared with those of control mice, the

  4. Reproduction and genotype identification of corticotropin-releasing hormone gene knockout mice%促肾上腺皮质激素释放激素基因敲除小鼠的繁殖与基因型鉴定

    Institute of Scientific and Technical Information of China (English)

    王海燕; 刘庆; 钟河江; 杨策; 黄苏娜; 严军; 蒋建新

    2011-01-01

    目的 探讨促肾上腺皮质激素释放激素(CRH)基因敲除(KO)小鼠饲养、繁殖及基因型鉴定的方法.方法 从美国Jackson实验室引进CRH KO小鼠,按照遗传学规则,对杂合子型(CRH+/-)小鼠进行配对繁殖,提取幼鼠尾部组织全基因组DNA,通过聚合酶链反应(PCR)对幼鼠基因型进行鉴定.结果 CRH KO纯合子型(CRH-/-)小鼠的繁殖和饲养均获得成功,采用PCR成功地对所获得的小鼠进行基因分析,在子代小鼠中存在野生纯合子型(CRH+/+)、杂合子型(CRH+/-)及CRH KO纯合子型(CRH-/-)小鼠.CRH-/-小鼠较另外2种基因型小鼠存活率明显下降,但3种基因型小鼠在出生后10 d及30 d体质量无明显差异.结论 正确的饲养繁殖以及鉴定方法可从杂合子型(CRH+/-)小鼠中获得CRH KO纯合子型(CRH-/-)小鼠.%Objective To explore the methods of breeding, reproductin and genotype identification of corticotropin-releasing hormone ( CRH)knockout( KO) mice.Methods CRH knockout mice were obtained from Jackson laboratory in USA.Heterozygous type (CRH+/- )mice were inbreeded according to genetic rules to yield CRH knockout mice.The genotypes of offspring were identified by polymerase chain reaction(PCR)using genomic DNA extracted from tissue of mice tails.Results Both breeding and reproductin of CRH KO heterozygous type(CRH+/- )mice were successful.PCR was used successfully for genetic analysis in mice obtained.There were wild homozygous genotype( CRH+ /+ ) , heterozygous genotype ( CRH + /- ) and CRH KO homozygous genotype( CRH-/- )in the offspring.Compared with other two genotype mice,survival rate of CRH- /- mice were significantly decreased.however, body mass of the three genotypes mice had no significant difference at 10 and 30 days after birth.Conclusion Appropriate reproductin , breeding and identification are effective methods to obtain CRH KO homozygous genotype( CRH -/- ) mice from heterozygous genotype( CRH+ / - ) mice.

  5. Female preproenkephalin-knockout mice display altered emotional responses.

    Science.gov (United States)

    Ragnauth, A; Schuller, A; Morgan, M; Chan, J; Ogawa, S; Pintar, J; Bodnar, R J; Pfaff, D W

    2001-02-13

    The endogenous opioid system has been implicated in sexual behavior, palatable intake, fear, and anxiety. The present study examined whether ovariectomized female transgenic preproenkephalin-knockout (PPEKO) mice and their wild-type and heterozygous controls displayed alterations in fear and anxiety paradigms, sucrose intake, and lordotic behavior. To examine stability of responding, three squads of the genotypes were tested across seasons over a 20-month period. In a fear-conditioning paradigm, PPEKO mice significantly increased freezing to both fear and fear + shock stimuli relative to controls. In the open field, PPEKO mice spent significantly less time and traversed significantly less distance in the center of an open field than wild-type controls. Further, PPEKO mice spent significantly less time and tended to be less active on the light side of a dark-light chamber than controls, indicating that deletion of the enkephalin gene resulted in exaggerated responses to fear or anxiety-provoking environments. These selective deficits were observed consistently across testing squads spanning 20 months and different seasons. In contrast, PPEKO mice failed to differ from corresponding controls in sucrose, chow, or water intake across a range (0.0001-20%) of sucrose concentrations and failed to differ in either lordotic or female approach to male behaviors when primed with estradiol and progesterone, thereby arguing strongly for the selectivity of a fear and anxiety deficit which was not caused by generalized and nonspecific debilitation. These transgenic data strongly suggest that opioids, and particularly enkephalin gene products, are acting naturally to inhibit fear and anxiety.

  6. 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.

  7. PosMed: Ranking genes and bioresources based on Semantic Web Association Study.

    Science.gov (United States)

    Makita, Yuko; Kobayashi, Norio; Yoshida, Yuko; Doi, Koji; Mochizuki, Yoshiki; Nishikata, Koro; Matsushima, Akihiro; Takahashi, Satoshi; Ishii, Manabu; Takatsuki, Terue; Bhatia, Rinki; Khadbaatar, Zolzaya; Watabe, Hajime; Masuya, Hiroshi; Toyoda, Tetsuro

    2013-07-01

    Positional MEDLINE (PosMed; http://biolod.org/PosMed) is a powerful Semantic Web Association Study engine that ranks biomedical resources such as genes, metabolites, diseases and drugs, based on the statistical significance of associations between user-specified phenotypic keywords and resources connected directly or inferentially through a Semantic Web of biological databases such as MEDLINE, OMIM, pathways, co-expressions, molecular interactions and ontology terms. Since 2005, PosMed has long been used for in silico positional cloning studies to infer candidate disease-responsible genes existing within chromosomal intervals. PosMed is redesigned as a workbench to discover possible functional interpretations for numerous genetic variants found from exome sequencing of human disease samples. We also show that the association search engine enhances the value of mouse bioresources because most knockout mouse resources have no phenotypic annotation, but can be associated inferentially to phenotypes via genes and biomedical documents. For this purpose, we established text-mining rules to the biomedical documents by careful human curation work, and created a huge amount of correct linking between genes and documents. PosMed associates any phenotypic keyword to mouse resources with 20 public databases and four original data sets as of May 2013.

  8. Hox genes and study of Hox genes in crustacean

    Institute of Scientific and Technical Information of China (English)

    HOU Lin; CHEN Zhijuan; XU Mingyu; LIN Shengguo; WANG Lu

    2004-01-01

    Homeobox genes have been discovered in many species. These genes are known to play a major role in specifying regional identity along the anterior-posterior axis of animals from a wide range of phyla.The products of the homeotic genes are a set of evolutionarily conserved transcription factors that control elaborate developmental processes and specify cell fates in metazoans. Crustacean, presenting a variety of body plans not encountered in any other class or phylum of the Metazoa, has been shown to possess a single set of homologous Hox genes like insect. The ancestral crustacean Hox gene complex comprised ten genes: eight homologous to the hometic Hox genes and two related to nonhomeotic genes presented within the insect Hox complexes. The crustacean in particular exhibits an abundant diversity segment specialization and tagmosis. This morphological diversity relates to the Hox genes. In crustacean body plan, different Hox genes control different segments and tagmosis.

  9. Gene set analysis for interpreting genetic studies

    DEFF Research Database (Denmark)

    Pers, Tune H

    2016-01-01

    Interpretation of genome-wide association study (GWAS) results is lacking behind the discovery of new genetic associations. Consequently, there is an urgent need for data-driven methods for interpreting genetic association studies. Gene set analysis (GSA) can identify aetiologic pathways and func......Interpretation of genome-wide association study (GWAS) results is lacking behind the discovery of new genetic associations. Consequently, there is an urgent need for data-driven methods for interpreting genetic association studies. Gene set analysis (GSA) can identify aetiologic pathways...

  10. Knockout driven reactions in complex molecules and their clusters

    Science.gov (United States)

    Gatchell, Michael; Zettergren, Henning

    2016-08-01

    Energetic ions lose some of their kinetic energy when interacting with electrons or nuclei in matter. Here, we discuss combined experimental and theoretical studies on such impulse driven reactions in polycyclic aromatic hydrocarbons (PAHs), fullerenes, and pure or mixed clusters of these molecules. These studies show that the nature of excitation is important for how complex molecular systems respond to ion/atom impact. Rutherford-like nuclear scattering processes may lead to prompt atom knockout and formation of highly reactive fragments, while heating of the molecular electron clouds in general lead to formation of more stable and less reactive fragments. In this topical review, we focus on recent studies of knockout driven reactions, and present new calculations of the angular dependent threshold (displacement) energies for such processes in PAHs. The so-formed fragments may efficiently form covalent bonds with neighboring molecules in clusters. These unique molecular growth processes may be important in astrophysical environments such as low velocity shock waves.

  11. Fmr1基因敲除小鼠耳蜗的GABAα1受体的表达%Expression of GABAα1 receptor of cochlea in FMR1 gene knock-out mice

    Institute of Scientific and Technical Information of China (English)

    李敏雄; 杜娜; 孙卫文; 黄月玲; 沈岩松; 戴丽军; 陈盛强; 马钊恩; 张建国

    2012-01-01

    Objective To observe cochlea morphology and expression of GABA a 1 receptor of cochlea in 4 weeks FMR1 KO mice and WT mice. Methods Four-week old Fmrl knockout mice were identified using the PCR technique.and immunohistochemistry to compare with the changes of expression of GABA a 1 receptor between FMR1 KO mice and WT mice cochlea. Results There were no difference in cochlea morphology between FMR1 KO mice and WT mice by HE dyeing. The expression of GABA a 1 receptor in cochlear in FMR-1K0 mice was decreased. Conclusion The expression of GABA a 1 receptor is incerased in cochlear in four-week old FMR-1K0 mice that might be associated with audiogenic seizure susceptibility of Fmrl knockout mice.%目的 对4周龄Fmr1基因敲除小鼠耳蜗的GABAα1受体表达进行观察,探讨耳蜗GABAα1受体的表达是否受FMRP的影响.方法 使用PCR技术对Fmr1基因敲除小鼠鉴定后,对4周龄的Fmr1基因敲除小鼠和野生型小鼠进行耳蜗的GABAα1受体免疫组织化学的表达观察,数据采用多因素方差分析处理.结果 耳蜗HE染色结果:4周龄组KO鼠较WT鼠形态学观察无差异.4周龄KO小鼠的耳蜗中GABAα1受体表达的平均阳性细胞数均低于WT小鼠,P<0.01,差异具有统计学意义.结论 GABAα1受体表达的降低可能与FMR1基因KO小鼠听源性惊厥发病有关.

  12. Nucleon and cluster knockout reactions induced in light nuclei by intermediate-energy protons

    Energy Technology Data Exchange (ETDEWEB)

    Vdovin, A.I.; Golovin, A.V.; Loshchakov, I.I.

    1987-11-01

    Experimental and theoretical studies of nucleon and cluster knockout reactions induced in light nuclei by intermediate-energy (30--150 MeV) protons are reviewed. The methods of theoretical analysis of knockout reactions are considered. The main attention is devoted to the t-matrix approximation with distorted waves. It is shown for the example of cluster knockout reactions how quasielastic and two-step processes can be coherently included in the matrix element when the t-matrix approximation is used.

  13. MAO A knockout attenuates adrenocortical response to various kinds of stress.

    Science.gov (United States)

    Popova, Nina K; Maslova, Larissa N; Morosova, Ekaterina A; Bulygina, Veta V; Seif, Isabelle

    2006-02-01

    The effect of a lack of the gene encoding monoamine oxidase A (MAO A) in transgenic Tg 8 mice on the corticosterone response to restraint, cold, water deprivation-induced, or social acute stress as well as chronic variable stress was studied. It was found that Tg 8 mice with genetic MAO A knockout and wild-type C3H/HeJ (C3H) strain showed similar plasma corticosterone resting level. MAO A knockout mice differed from C3H mice by attenuated response to restraint (60 min), cold (4 degrees C, 60 min), and water deprivation (48 h) as well as to a chronic (15 days) variable stress. No difference between Tg 8 and C3H strains in the response to psychosocial stress (encounters for 30 min of six previously isolated mice) has been found. ACTH administration to dexamethasone-pretreated mice produced a similar corticosterone effect in Tg 8 and C3H mice, indicating that the decreased stress response in MAO A-deficient mice was due rather to the central mechanisms regulating stress-induced ACTH release than to adrenocortical responsiveness to ACTH.

  14. Studying Functions of All Yeast Genes Simultaneously

    Science.gov (United States)

    Stolc, Viktor; Eason, Robert G.; Poumand, Nader; Herman, Zelek S.; Davis, Ronald W.; Anthony Kevin; Jejelowo, Olufisayo

    2006-01-01

    A method of studying the functions of all the genes of a given species of microorganism simultaneously has been developed in experiments on Saccharomyces cerevisiae (commonly known as baker's or brewer's yeast). It is already known that many yeast genes perform functions similar to those of corresponding human genes; therefore, by facilitating understanding of yeast genes, the method may ultimately also contribute to the knowledge needed to treat some diseases in humans. Because of the complexity of the method and the highly specialized nature of the underlying knowledge, it is possible to give only a brief and sketchy summary here. The method involves the use of unique synthetic deoxyribonucleic acid (DNA) sequences that are denoted as DNA bar codes because of their utility as molecular labels. The method also involves the disruption of gene functions through deletion of genes. Saccharomyces cerevisiae is a particularly powerful experimental system in that multiple deletion strains easily can be pooled for parallel growth assays. Individual deletion strains recently have been created for 5,918 open reading frames, representing nearly all of the estimated 6,000 genetic loci of Saccharomyces cerevisiae. Tagging of each deletion strain with one or two unique 20-nucleotide sequences enables identification of genes affected by specific growth conditions, without prior knowledge of gene functions. Hybridization of bar-code DNA to oligonucleotide arrays can be used to measure the growth rate of each strain over several cell-division generations. The growth rate thus measured serves as an index of the fitness of the strain.

  15. Establishment of 6-phosphofructo-2-kinase/ fructose-2,6-biphosphatase 3 gene knockout mice%6-磷酸果糖激酶-2/果糖双磷酸酶-2同工酶3基因敲除小鼠模型的构建

    Institute of Scientific and Technical Information of China (English)

    王骏; 李师耿; 王喻; 彭叔彬; 陈延雄; 韩飞; 李骏; 温星桥

    2015-01-01

    目的 建立6-磷酸果糖激酶-2/果糖双磷酸酶-2同工酶3(PFKFB3)基因敲除小鼠模型.方法 利用类转录激活样效应因子核酸酶(TALEN)技术,通过构建针对PFKFB3基因的TALEN质粒,并将构建好的TALEN质粒在体外反转录为mRNA.利用原核显微注射分别将0.1μl转录后的浓度为50 ng/μl的mRNA注射到C57BL/6品系小鼠受精卵中,将受精卵回送到ICR代孕母鼠输卵管中,得到F0代基因敲除杂合子小鼠.将F0代饲养至10周龄后合笼,从而构建基因敲除纯合子小鼠.所有子代鼠出生1周后剪尾,提取RNA后反转录,PCR产物作为模板进行基因测序鉴定基因型.结果 通过TALEN技术成功构建了F0代基因敲除杂合子小鼠3只,基因测序结果表明分别于靶基因位置缺失了10、4、1对碱基对;因PFKFB3基因敲除纯合子具有胚胎致死性,6只F1代基因敲除小鼠的基因测序结果显示,针对靶基因,编号4、5的小鼠缺失了1对碱基对,6号小鼠缺失4对碱基对,7、8、9号小鼠缺失10对碱基对.结论 成功构建了PFKFB3基因敲除杂合子(+/-)小鼠.%Objective To generate 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 3 (PFKFB3) knockout mice model.Methods The gene knockout mice were constructed by means of transcription activator-like effector nuclease (TALEN) technique.TALEN vectors were constructed targeting sequence of PFKFB3 and the TALEN mRNA was generated by in vitro transcription.Then 0.1 μl mRNA which has been diluted to 50 ng/μl was injected into fertilized C57BL/6 eggs.They were then implanted in ICR female mice for production of F0 generation knockout mouse.To generate homozygote gene knockout mice, 10-weeks-old F0 generation female mice were mated with male.The RNA was extracted from tail tips of mouse pups, then subjected to reverse transcription and the polymerase chain reaction (PCR) products were used as templates for sequencing analysis.Results By means of TALEN technique, three heterozygote PFKFB3

  16. 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.

  17. A study of bacterial gene regulatory mechanisms

    DEFF Research Database (Denmark)

    Hansen, Sabine

    the different regulatory mechanisms affect system dynamics. We have designed a synthetic gene regulatory network (GRN) in bacterial cells that enables us to study the dynamics of GRNs. The results presented in this PhD thesis show that model equations based on the established mechanisms of action of each...... of a particular type of regulatory mechanism. The synthetic system presented in this thesis is, to our knowledge, the first of its kind to allow a direct comparison of the dynamic behaviors of gene regulatory networks that employ different mechanisms of regulation. In addition to studying the dynamic behavior...... of GRNs this thesis also provided the first evidence of the sensor histidine kinase VC1831 being an additional player in the Vibrio cholerae quorum sensing (QS) GRN. Bacteria use a process of cell-cell communication called QS which enable the bacterial cells to collectively control their gene expression...

  18. Generation of myostatin B knockout yellow catfish (Tachysurus fulvidraco) using transcription activator-like effector nucleases.

    Science.gov (United States)

    Dong, Zhangji; Ge, Jiachun; Xu, Zhiqiang; Dong, Xiaohua; Cao, Shasha; Pan, Jianlin; Zhao, Qingshun

    2014-06-01

    Myostatin (Mstn), a member of the transforming growth factor β superfamily, plays an inhibiting role in mammalian muscle growth. Mammals like human, cattle, mouse, sheep, and dog carrying null alleles of Mstn display a double-muscle phenotype. Mstn is conserved in fish; however, little is known whether the fish with mutated mstn display a similar phenotype to mammals because of the lack of mutant fish with mstn null alleles. Previously, we knocked out one of the duplicated copies of myostatin gene (mstna) in yellow catfish using zinc-finger nucleases. In this study, we report the identification of the second myostatin gene (mstnb) and knockout of mstnb in yellow catfish. The gene comprises three exons. It is predicted to encode 373 amino acid residues. The predicted protein exhibits 59.3% identity with yellow catfish Mstna and 57.3% identity with human MSTN. Employing TALEN (transcription activator-like effector nucleases) technology, we obtained two founders (from four randomly selected founders) of yellow catfish carrying the mutated mstnb gene in their germ cells. Totally, six mutated alleles of mstnb were obtained from the founders. Among the six alleles, four are nonframeshift and two are frameshift mutation. The frameshift mutated alleles include mstnb(nju22), an 8 bp deletion, and mstnb(nju24), a complex type of mutation comprising a 7 bp deletion and a 12 bp insertion. They are predicted to encode function null Mstnb. Our results will help to understand the roles of mstn genes in fish growth.

  19. Detection of gene x gene interactions in genome-wide association studies of human population data

    National Research Council Canada - National Science Library

    Musani, Solomon K; Shriner, Daniel; Liu, Nianjun; Feng, Rui; Coffey, Christopher S; Yi, Nengjun; Tiwari, Hemant K; Allison, David B

    2007-01-01

    Empirical evidence supporting the commonality of gene x gene interactions, coupled with frequent failure to replicate results from previous association studies, has prompted statisticians to develop...

  20. Analysis of microsatellite polymorphism in inbred knockout mice.

    Science.gov (United States)

    Zuo, Baofen; Du, Xiaoyan; Zhao, Jing; Yang, Huixin; Wang, Chao; Wu, Yanhua; Lu, Jing; Wang, Ying; Chen, Zhenwen

    2012-01-01

    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.

  1. Analysis of microsatellite polymorphism in inbred knockout mice.

    Directory of Open Access Journals (Sweden)

    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.

  2. Brief Report: Altered Social Behavior in Isolation-Reared "Fmr1" Knockout Mice

    Science.gov (United States)

    Heitzer, Andrew M.; Roth, Alexandra K.; Nawrocki, Lauren; Wrenn, Craige C.; Valdovinos, Maria G.

    2013-01-01

    Social behavior abnormalities in Fragile X syndrome (FXS) are characterized by social withdrawal, anxiety, and deficits in social cognition. To assess these deficits, a model of FXS, the "Fmr1" knockout mouse ("Fmr1" KO), has been utilized. This mouse model has a null mutation in the fragile X mental retardation 1 gene ("Fmr1") and displays…

  3. Generation of Rag1-knockout immunodeficient rats and mice using engineered meganucleases.

    Science.gov (United States)

    Ménoret, Séverine; Fontanière, Sandra; Jantz, Derek; Tesson, Laurent; Thinard, Reynald; Rémy, Séverine; Usal, Claire; Ouisse, Laure-Hélène; Fraichard, Alexandre; Anegon, Ignacio

    2013-02-01

    Despite the recent availability of gene-specific nucleases, such as zinc-finger nucleases (ZFNs) and transcription activator-like nucleases (TALENs), there is still a need for new tools to modify the genome of different species in an efficient, rapid, and less costly manner. One aim of this study was to apply, for the first time, engineered meganucleases to mutate an endogenous gene in animal zygotes. The second aim was to target the mouse and rat recombination activating gene 1 (Rag1) to describe, for the first time, Rag1 knockout immunodeficient rats. We microinjected a plasmid encoding a meganuclease for Rag1 into the pronucleus of mouse and rat zygotes. Mutant animals were detected by PCR sequencing of the targeted sequence. A homozygous RAG1-deficient rat line was generated and immunophenotyped. Meganucleases were efficient, because 3.4 and 0.6% of mouse and rat microinjected zygotes, respectively, generated mutated animals. RAG1-deficient rats showed significantly decreased proportions and numbers of immature and mature T and B lymphocytes and normal NK cells vs. littermate wild-type controls. In summary, we describe the use of engineered meganucleases to inactivate an endogenous gene with efficiencies comparable to those of ZFNs and TALENs. Moreover, we generated an immunodeficient rat line useful for studies in which there is a need for biological parameters to be analyzed in the absence of immune responses.

  4. Homozygous and Heterozygous p53 Knockout Rats Develop Metastasizing Sarcomas with High Frequency

    Science.gov (United States)

    van Boxtel, Ruben; Kuiper, Raoul V.; Toonen, Pim W.; van Heesch, Sebastiaan; Hermsen, Roel; de Bruin, Alain; Cuppen, Edwin

    2011-01-01

    The TP53 tumor suppressor gene is mutated in the majority of human cancers. Inactivation of p53 in a variety of animal models results in early-onset tumorigenesis, reflecting the importance of p53 as a gatekeeper tumor suppressor. We generated a mutant Tp53 allele in the rat using a target-selected mutagenesis approach. Here, we report that homozygosity for this allele results in complete loss of p53 function. Homozygous mutant rats predominantly develop sarcomas with an onset of 4 months of age with a high occurrence of pulmonary metastases. Heterozygous rats develop sarcomas starting at 8 months of age. Molecular analysis revealed that these tumors exhibit a loss-of-heterozygosity of the wild-type Tp53 allele. These unique features make this rat highly complementary to other rodent p53 knockout models and a versatile tool for investigating tumorigenesis processes as well as genotoxic studies. PMID:21854749

  5. Effects of clonidine and methylphenidate on motor activity in Fmr1 knockout mice.

    Science.gov (United States)

    Wrenn, Craige C; Heitzer, Andrew M; Roth, Alexandra K; Nawrocki, Lauren; Valdovinos, Maria G

    2015-01-12

    Fragile X syndrome (FXS), a disorder caused by a mutation in the FMR1 gene, is often associated with Attention Deficit Hyperactivity Disorder (ADHD). Common treatments for the hyperactivity often seen in ADHD involve the use of stimulants and α2-adrenergic agonists. The Fmr1 knockout (KO) mouse has been found to be a valid model for FXS both biologically and behaviorally. Of particular interest to our research, the Fmr1 KO mouse has been demonstrated to show increased locomotion in comparison to wild type (WT) littermates. In the present study, we assessed the effects of clonidine (0.05 mg/kg) and methylphenidate (5 mg/kg) on motor activity in Fmr1 KO mice and their WT littermates in the open field test. Results showed that methylphenidate increased motor activity in both genotypes. Clonidine decreased motor activity in both genotypes, but the effect was delayed in the Fmr1 KO mice.

  6. Msx homeobox gene family and craniofacial development

    Institute of Scientific and Technical Information of China (English)

    SYLVIA ALAPPAT; ZUN YI ZHANG; YI PING CHEN

    2003-01-01

    Vertebrate Msx genes are unlinked,homeobox-containing genes that bear homology to the Drosophila muscle segment homeobox gene.These genes are expressed at multiple sites of tissue-tissue interactions during vertebrate embryonic development.Inductive interactions mediated by the Msx genes are essential for normal craniofacial,limb and ectodermal organ morphogenesis,and are also essential to survival in mice,as manifested by the phenotypic abnormalities shown in knockout mice and in humans.This review summarizes studies on the expression,regulation,and functional analysis of Msx genes that bear relevance to craniofacial development in humans and mice.

  7. Auxin/AID versus conventional knockouts: distinguishing the roles of CENP-T/W in mitotic kinetochore assembly and stability.

    Science.gov (United States)

    Wood, Laura; Booth, Daniel G; Vargiu, Giulia; Ohta, Shinya; deLima Alves, Flavia; Samejima, Kumiko; Fukagawa, Tatsuo; Rappsilber, Juri; Earnshaw, William C

    2016-01-01

    Most studies using knockout technologies to examine protein function have relied either on shutting off transcription (conventional conditional knockouts with tetracycline-regulated gene expression or gene disruption) or destroying the mature mRNA (RNAi technology). In both cases, the target protein is lost at a rate determined by its intrinsic half-life. Thus, protein levels typically fall over at least 1-3 days, and cells continue to cycle while exposed to a decreasing concentration of the protein. Here we characterise the kinetochore proteome of mitotic chromosomes isolated from a cell line in which the essential kinetochore protein CENP-T is present as an auxin-inducible degron (AID) fusion protein that is fully functional and able to support the viability of the cells. Stripping of the protein from chromosomes in early mitosis via targeted proteasomal degradation reveals the dependency of other proteins on CENP-T for their maintenance in kinetochores. We compare these results with the kinetochore proteome of conventional CENP-T/W knockouts. As the cell cycle is mostly formed from G1, S and G2 phases a gradual loss of CENP-T/W levels is more likely to reflect dependencies associated with kinetochore assembly pre-mitosis and upon entry into mitosis. Interestingly, a putative super-complex involving Rod-Zw10-zwilch (RZZ complex), Spindly, Mad1/Mad2 and CENP-E requires the function of CENP-T/W during kinetochore assembly for its stable association with the outer kinetochore, but once assembled remains associated with chromosomes after stripping of CENP-T during mitosis. This study highlights the different roles core kinetochore components may play in the assembly of kinetochores (upon entry into mitosis) versus the maintenance of specific components (during mitosis).

  8. A Study on Genes of Bayanbulak Sheep

    Directory of Open Access Journals (Sweden)

    Beiyao Zuo

    2013-01-01

    Full Text Available The average twin lambing rate of Bayanbulak sheep is 2% to 3%. However, a flock of sheep with a close genetic relationship and an average of 2 to 3 lambs per birth has been found recently. To determine the major genes controlling the prolificacy of the flock in the present study, the flock was designated A while 100 normal Bayanbulak sheep were randomly selected to comprise the control flock B. Ligase detection reaction method was applied to detect and analyze the 10 mutational loci of the 3 candidate prolificacy genes including bone morphogenetic protein type I receptors, bone morphogenetic protein 15, and growth differentiation factor 9. The 10 mutational loci are as follows: FecB locus of the BMPR-IB gene; FecXI, FecXB, FecXL, FecXH, FecXG, and FecXR of the BMP15 gene; and G1, G8, and FecTT of the GDF9 gene. Two mutations including BMPR-IB/FecB and GDF9/G1 were found in Bayanbulak sheep. Independence test results of the two flocks demonstrate that the FecB locus has a significant effect on the lambing number of Bayanbulak sheep. However, the mutation frequency of the G1 locus in GDF9 is very low. Independence test results demonstrate that the GDF9 locus does not have a significant impact on the lambing performance of Bayanbulak sheep. Among the 10 detected loci, BMPR-IB/FecB is the major gene that influences the high lambing rate of Bayanbulak sheep.

  9. Fatty acid homeostasis and induction of lipid regulatory genes in skeletal muscles of peroxisome proliferator-activated receptor (PPAR) alpha knock-out mice. Evidence for compensatory regulation by PPAR delta

    National Research Council Canada - National Science Library

    Muoio, Deborah M; MacLean, Paul S; Lang, David B; Li, Shi; Houmard, Joseph A; Way, James M; Winegar, Deborah A; Corton, J Christopher; Dohm, G Lynis; Kraus, William E

    2002-01-01

    Ablation of peroxisome proliferator activated receptor (PPAR) alpha, a lipid-activated transcription factor that regulates expression of beta-oxidative genes, results in profound metabolic abnormalities in liver and heart...

  10. Microarray analysis of E9.5 reduced folate carrier (RFC1; Slc19a1 knockout embryos reveals altered expression of genes in the cubilin-megalin multiligand endocytic receptor complex

    Directory of Open Access Journals (Sweden)

    Bauer Linda K

    2008-04-01

    Full Text Available Abstract Background The reduced folate carrier (RFC1 is an integral membrane protein and facilitative anion exchanger that mediates delivery of 5-methyltetrahydrofolate into mammalian cells. Adequate maternal-fetal transport of folate is necessary for normal embryogenesis. Targeted inactivation of the murine RFC1 gene results in post-implantation embryolethality, but daily folic acid supplementation of pregnant dams prolongs survival of homozygous embryos until mid-gestation. At E10.5 RFC1-/- embryos are developmentally delayed relative to wildtype littermates, have multiple malformations, including neural tube defects, and die due to failure of chorioallantoic fusion. The mesoderm is sparse and disorganized, and there is a marked absence of erythrocytes in yolk sac blood islands. The identification of alterations in gene expression and signaling pathways involved in the observed dysmorphology following inactivation of RFC1-mediated folate transport are the focus of this investigation. Results Affymetrix microarray analysis of the relative gene expression profiles in whole E9.5 RFC1-/- vs. RFC1+/+ embryos identified 200 known genes that were differentially expressed. Major ontology groups included transcription factors (13.04%, and genes involved in transport functions (ion, lipid, carbohydrate (11.37%. Genes that code for receptors, ligands and interacting proteins in the cubilin-megalin multiligand endocytic receptor complex accounted for 9.36% of the total, followed closely by several genes involved in hematopoiesis (8.03%. The most highly significant gene network identified by Ingenuity™ Pathway analysis included 12 genes in the cubilin-megalin multiligand endocytic receptor complex. Altered expression of these genes was validated by quantitative RT-PCR, and immunohistochemical analysis demonstrated that megalin protein expression disappeared from the visceral yolk sac of RFC1-/- embryos, while cubilin protein was widely misexpressed

  11. A knockout mutation of a constitutive GPCR in Tetrahymena decreases both G-protein activity and chemoattraction.

    Directory of Open Access Journals (Sweden)

    Thomas J Lampert

    Full Text Available Although G-protein coupled receptors (GPCRs are a common element in many chemosensory transduction pathways in eukaryotic cells, no GPCR or regulated G-protein activity has yet been shown in any ciliate. To study the possible role for a GPCR in the chemoresponses of the ciliate Tetrahymena, we have generated a number of macronuclear gene knockouts of putative GPCRs found in the Tetrahymena Genome database. One of these knockout mutants, called G6, is a complete knockout of a gene that we call GPCR6 (TTHERM_00925490. Based on sequence comparisons, the Gpcr6p protein belongs to the Rhodopsin Family of GPCRs. Notably, Gpcr6p shares highest amino acid sequence homologies to GPCRs from Paramecium and several plants. One of the phenotypes of the G6 mutant is a decreased responsiveness to the depolarizing ions Ba²⁺ and K⁺, suggesting a decrease in basal excitability (decrease in Ca²⁺ channel activity. The other major phenotype of G6 is a loss of chemoattraction to lysophosphatidic acid (LPA and proteose peptone (PP, two known chemoattractants in Tetrahymena. Using microsomal [³⁵S]GTPγS binding assays, we found that wild-type (CU427 have a prominent basal G-protein activity. This activity is decreased to the same level by pertussis toxin (a G-protein inhibitor, addition of chemoattractants, or the G6 mutant. Since the basal G-protein activity is decreased by the GPCR6 knockout, it is likely that this gene codes for a constitutively active GPCR in Tetrahymena. We propose that chemoattractants like LPA and PP cause attraction in Tetrahymena by decreasing the basal G-protein stimulating activity of Gpcr6p. This leads to decreased excitability in wild-type and longer runs of smooth forward swimming (less interrupted by direction changes towards the attractant. Therefore, these attractants may work as inverse agonists through the constitutively active Gpcr6p coupled to a pertussis-sensitive G-protein.

  12. Does murine spermatogenesis require WNT signalling? A lesson from Gpr177 conditional knockout mouse models.

    Science.gov (United States)

    Chen, Su-Ren; Tang, J-X; Cheng, J-M; Hao, X-X; Wang, Y-Q; Wang, X-X; Liu, Y-X

    2016-06-30

    Wingless-related MMTV integration site (WNT) proteins and several other components of the WNT signalling pathway are expressed in the murine testes. However, mice mutant for WNT signalling effector β-catenin using different Cre drivers have phenotypes that are inconsistent with each other. The complexity and overlapping expression of WNT signalling cascades have prevented researchers from dissecting their function in spermatogenesis. Depletion of the Gpr177 gene (the mouse orthologue of Drosophila Wntless), which is required for the secretion of various WNTs, makes it possible to genetically dissect the overall effect of WNTs in testis development. In this study, the Gpr177 gene was conditionally depleted in germ cells (Gpr177(flox/flox), Mvh-Cre; Gpr177(flox/flox), Stra8-Cre) and Sertoli cells (Gpr177(flox/flox), Amh-Cre). No obvious defects in fertility and spermatogenesis were observed in these three Gpr177 conditional knockout (cKO) mice at 8 weeks. However, late-onset testicular atrophy and fertility decline in two germ cell-specific Gpr177 deletion mice were noted at 8 months. In contrast, we did not observe any abnormalities of spermatogenesis and fertility, even in 8-month-old Gpr177(flox/flox), Amh-Cre mice. Elevation of reactive oxygen species (ROS) was detected in Gpr177 cKO germ cells and Sertoli cells and exhibited an age-dependent manner. However, significant increase in the activity of Caspase 3 was only observed in germ cells from 8-month-old germ cell-specific Gpr177 knockout mice. In conclusion, GPR177 in Sertoli cells had no apparent influence on spermatogenesis, whereas loss of GPR177 in germ cells disrupted spermatogenesis in an age-dependent manner via elevating ROS levels and triggering germ cell apoptosis.

  13. With Reference to Reference Genes: A Systematic Review of Endogenous Controls in Gene Expression Studies.

    Science.gov (United States)

    Chapman, Joanne R; Waldenström, Jonas

    2015-01-01

    The choice of reference genes that are stably expressed amongst treatment groups is a crucial step in real-time quantitative PCR gene expression studies. Recent guidelines have specified that a minimum of two validated reference genes should be used for normalisation. However, a quantitative review of the literature showed that the average number of reference genes used across all studies was 1.2. Thus, the vast majority of studies continue to use a single gene, with β-actin (ACTB) and/or glyceraldehyde 3-phosphate dehydrogenase (GAPDH) being commonly selected in studies of vertebrate gene expression. Few studies (15%) tested a panel of potential reference genes for stability of expression before using them to normalise data. Amongst studies specifically testing reference gene stability, few found ACTB or GAPDH to be optimal, whereby these genes were significantly less likely to be chosen when larger panels of potential reference genes were screened. Fewer reference genes were tested for stability in non-model organisms, presumably owing to a dearth of available primers in less well characterised species. Furthermore, the experimental conditions under which real-time quantitative PCR analyses were conducted had a large influence on the choice of reference genes, whereby different studies of rat brain tissue showed different reference genes to be the most stable. These results highlight the importance of validating the choice of normalising reference genes before conducting gene expression studies.

  14. Novel insight into glucagon receptor action: lessons from knockout and transgenic mouse models

    OpenAIRE

    Vuguin, P. M.; Charron, M. J.

    2011-01-01

    Using knockout and transgenic technology, genetically modified animal models allowed us to understand the role of glucagon signalling in metabolism. Mice with a global deletion of the glucagon receptor gene (Gcgr) were designed using gene targeting. The phenotype of Gcgr−/− mouse provided important clues about the role of Gcgr in foetal growth, pancreatic development and glucose and lipid homeostasis. The lack of Gcgr activation was associated with: (i) hypoglycaemic pregnancies, poor foetal ...

  15. Normal maternal behavior, but increased pup mortality, in conditional oxytocin receptor knockout females.

    Science.gov (United States)

    Macbeth, Abbe H; Stepp, Jennifer E; Lee, Heon-Jin; Young, W Scott; Caldwell, Heather K

    2010-10-01

    Oxytocin (Oxt) and the Oxt receptor (Oxtr) are implicated in the onset of maternal behavior in a variety of species. Recently, we developed two Oxtr knockout lines: a total body knockout (Oxtr-/-) and a conditional Oxtr knockout (OxtrFB/FB) in which the Oxtr is lacking only in regions of the forebrain, allowing knockout females to potentially nurse and care for their biological offspring. In the current study, we assessed maternal behavior of postpartum OxtrFB/FB females toward their own pups and maternal behavior of virgin Oxtr-/- females toward foster pups and compared knockouts of both lines to wildtype (Oxtr+/+) littermates. We found that both Oxtr-/- and OxtrFB/FB females appear to have largely normal maternal behaviors. However, with first litters, approximately 40% of the OxtrFB/FB knockout dams experienced high pup mortality, compared to fewer than 10% of the Oxtr+/+ dams. We then went on to test whether or not this phenotype occurred in subsequent litters or when the dams were exposed to an environmental disturbance. We found that regardless of the degree of external disturbance, OxtrFB/FB females lost more pups on their first and second litters compared to wildtype females. Possible reasons for higher pup mortality in OxtrFB/FB females are discussed.

  16. Cytochrome P450 1b1 in polycyclic aromatic hydrocarbon (PAH)-induced skin carcinogenesis: Tumorigenicity of individual PAHs and coal-tar extract, DNA adduction and expression of select genes in the Cyp1b1 knockout mouse

    Energy Technology Data Exchange (ETDEWEB)

    Siddens, Lisbeth K. [Department of Environmental and Molecular Toxicology, Oregon State University, Corvallis, OR 97331 (United States); Superfund Research Center, Oregon State University, Corvallis, OR 97331 (United States); Bunde, Kristi L. [College of Veterinary Medicine, Oregon State University, Corvallis, OR 97331 (United States); Harper, Tod A. [Department of Environmental and Molecular Toxicology, Oregon State University, Corvallis, OR 97331 (United States); Linus Pauling Institute, Oregon State University, Corvallis, OR 97331 (United States); Environmental Health Sciences Center, Oregon State University, Corvallis, OR 97331 (United States); McQuistan, Tammie J. [Superfund Research Center, Oregon State University, Corvallis, OR 97331 (United States); Linus Pauling Institute, Oregon State University, Corvallis, OR 97331 (United States); Löhr, Christiane V. [Environmental Health Sciences Center, Oregon State University, Corvallis, OR 97331 (United States); College of Veterinary Medicine, Oregon State University, Corvallis, OR 97331 (United States); Bramer, Lisa M. [Applied Statistics and Computational Modeling, Pacific Northwest National Laboratory, Richland, WA 99352 (United States); Waters, Katrina M. [Superfund Research Center, Oregon State University, Corvallis, OR 97331 (United States); Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352 (United States); Tilton, Susan C. [Department of Environmental and Molecular Toxicology, Oregon State University, Corvallis, OR 97331 (United States); Superfund Research Center, Oregon State University, Corvallis, OR 97331 (United States); Krueger, Sharon K. [Department of Environmental and Molecular Toxicology, Oregon State University, Corvallis, OR 97331 (United States); Superfund Research Center, Oregon State University, Corvallis, OR 97331 (United States); Linus Pauling Institute, Oregon State University, Corvallis, OR 97331 (United States); and others

    2015-09-01

    FVB/N mice wild-type, heterozygous or null for Cyp 1b1 were used in a two-stage skin tumor study comparing PAH, benzo[a]pyrene (BaP), dibenzo[def,p]chrysene (DBC), and coal tar extract (CTE, SRM 1597a). Following 20 weeks of promotion with TPA the Cyp 1b1 null mice, initiated with DBC, exhibited reductions in incidence, multiplicity, and progression. None of these effects were observed with BaP or CTE. The mechanism of Cyp 1b1-dependent alteration of DBC skin carcinogenesis was further investigated by determining expression of select genes in skin from DBC-treated mice 2, 4 and 8 h post-initiation. A significant reduction in levels of Cyp 1a1, Nqo1 at 8 h and Akr 1c14 mRNA was observed in Cyp 1b1 null (but not wt or het) mice, whereas no impact was observed in Gst a1, Nqo 1 at 2 and 4 h or Akr 1c19 at any time point. Cyp 1b1 mRNA was not elevated by DBC. The major covalent DNA adducts, dibenzo[def,p]chrysene-(±)-11,12-dihydrodiol-cis and trans-13,14-epoxide-deoxyadenosine (DBCDE-dA) were quantified by UHPLC-MS/MS 8 h post-initiation. Loss of Cyp1 b1 expression reduced DBCDE-dA adducts in the skin but not to a statistically significant degree. The ratio of cis- to trans-DBCDE-dA adducts was higher in the skin than other target tissues such as the spleen, lung and liver (oral dosing). These results document that Cyp 1b1 plays a significant role in bioactivation and carcinogenesis of DBC in a two-stage mouse skin tumor model and that loss of Cyp 1b1 has little impact on tumor response with BaP or CTE as initiators. - Highlights: • Cyp1b1 null mice exhibit lower skin cancer sensitivity to DBC but not BaP or CTE. • Cyp1b1 expression impacts expression of other PAH metabolizing enzymes. • cis/trans-DBCDE-dA ratio significantly higher in the skin than the spleen, lung or liver • Potency of DBC and CTE in mouse skin is higher than predicted by RPFs.

  17. A gene-based information gain method for detecting gene-gene interactions in case-control studies.

    Science.gov (United States)

    Li, Jin; Huang, Dongli; Guo, Maozu; Liu, Xiaoyan; Wang, Chunyu; Teng, Zhixia; Zhang, Ruijie; Jiang, Yongshuai; Lv, Hongchao; Wang, Limei

    2015-11-01

    Currently, most methods for detecting gene-gene interactions (GGIs) in genome-wide association studies are divided into SNP-based methods and gene-based methods. Generally, the gene-based methods can be more powerful than SNP-based methods. Some gene-based entropy methods can only capture the linear relationship between genes. We therefore proposed a nonparametric gene-based information gain method (GBIGM) that can capture both linear relationship and nonlinear correlation between genes. Through simulation with different odds ratio, sample size and prevalence rate, GBIGM was shown to be valid and more powerful than classic KCCU method and SNP-based entropy method. In the analysis of data from 17 genes on rheumatoid arthritis, GBIGM was more effective than the other two methods as it obtains fewer significant results, which was important for biological verification. Therefore, GBIGM is a suitable and powerful tool for detecting GGIs in case-control studies.

  18. The KCNE genes in hypertrophic cardiomyopathy: a candidate gene study

    DEFF Research Database (Denmark)

    Hedley, Paula L; Haundrup, Ole; Andersen, Paal S

    2011-01-01

    The gene family KCNE1-5, which encode modulating β-subunits of several repolarising K+-ion channels, has been associated with genetic cardiac diseases such as long QT syndrome, atrial fibrillation and Brugada syndrome. The minK peptide, encoded by KCNE1, is attached to the Z-disc of the sarcomere...... as well as the T-tubules of the sarcolemma. It has been suggested that minK forms part of an "electro-mechanical feed-back" which links cardiomyocyte stretching to changes in ion channel function. We examined whether mutations in KCNE genes were associated with hypertrophic cardiomyopathy (HCM), a genetic...

  19. Metabolomic Characterization of Knockout Mutants in Arabidopsis: Development of a Metabolite Profiling Database for Knockout Mutants in Arabidopsis.

    Science.gov (United States)

    Fukushima, Atsushi; Kusano, Miyako; Mejia, Ramon Francisco; Iwasa, Mami; Kobayashi, Makoto; Hayashi, Naomi; Watanabe-Takahashi, Akiko; Narisawa, Tomoko; Tohge, Takayuki; Hur, Manhoi; Wurtele, Eve Syrkin; Nikolau, Basil J; Saito, Kazuki

    2014-05-14

    Despite recent intensive research efforts in functional genomics, the functions of only a limited number of Arabidopsis (Arabidopsis thaliana) genes have been determined experimentally, and improving gene annotation remains a major challenge in plant science. As metabolite profiling can characterize the metabolomic phenotype of a genetic perturbation in the plant metabolism, it provides clues to the function(s) of genes of interest. We chose 50 Arabidopsis mutants, including a set of characterized and uncharacterized mutants, that resemble wild-type plants. We performed metabolite profiling of the plants using gas chromatography-mass spectrometry. To make the data set available as an efficient public functional genomics tool for hypothesis generation, we developed the Metabolite Profiling Database for Knock-Out Mutants in Arabidopsis (MeKO). It allows the evaluation of whether a mutation affects metabolism during normal plant growth and contains images of mutants, data on differences in metabolite accumulation, and interactive analysis tools. Nonprocessed data, including chromatograms, mass spectra, and experimental metadata, follow the guidelines set by the Metabolomics Standards Initiative and are freely downloadable. Proof-of-concept analysis suggests that MeKO is highly useful for the generation of hypotheses for genes of interest and for improving gene annotation. MeKO is publicly available at http://prime.psc.riken.jp/meko/.

  20. The KCNE genes in hypertrophic cardiomyopathy: a candidate gene study

    Directory of Open Access Journals (Sweden)

    Moolman-Smook Johanna C

    2011-10-01

    Full Text Available Abstract Background The gene family KCNE1-5, which encode modulating β-subunits of several repolarising K+-ion channels, has been associated with genetic cardiac diseases such as long QT syndrome, atrial fibrillation and Brugada syndrome. The minK peptide, encoded by KCNE1, is attached to the Z-disc of the sarcomere as well as the T-tubules of the sarcolemma. It has been suggested that minK forms part of an "electro-mechanical feed-back" which links cardiomyocyte stretching to changes in ion channel function. We examined whether mutations in KCNE genes were associated with hypertrophic cardiomyopathy (HCM, a genetic disease associated with an improper hypertrophic response. Results The coding regions of KCNE1, KCNE2, KCNE3, KCNE4, and KCNE5 were examined, by direct DNA sequencing, in a cohort of 93 unrelated HCM probands and 188 blood donor controls. Fifteen genetic variants, four previously unknown, were identified in the HCM probands. Eight variants were non-synonymous and one was located in the 3'UTR-region of KCNE4. No disease-causing mutations were found and no significant difference in the frequency of genetic variants was found between HCM probands and controls. Two variants of likely functional significance were found in controls only. Conclusions Mutations in KCNE genes are not a common cause of HCM and polymorphisms in these genes do not seem to be associated with a propensity to develop arrhythmia

  1. A study of bacterial gene regulatory mechanisms

    DEFF Research Database (Denmark)

    Hansen, Sabine

    regulator studied accurately reproduced the experimental data. Simulations of system dynamics reveals that even two step regulatory cascades significantly increase response times compared to direct allosteric regulation of a transcription factor. It is observed that while many system behaviors...... of GRNs this thesis also provided the first evidence of the sensor histidine kinase VC1831 being an additional player in the Vibrio cholerae quorum sensing (QS) GRN. Bacteria use a process of cell-cell communication called QS which enable the bacterial cells to collectively control their gene expression...

  2. Engineering Clostridium acetobutylicum with a histidine kinase knockout for enhanced n-butanol tolerance and production.

    Science.gov (United States)

    Xu, Mengmeng; Zhao, Jingbo; Yu, Le; Tang, I-Ching; Xue, Chuang; Yang, Shang-Tian

    2015-01-01

    Clostridium acetobutylicum JB200, a mutant strain of C. acetobutylicum ATCC 55025 obtained through strain evolution in a fibrous bed bioreactor, had high butanol tolerance and produced up to ~21 g/L butanol from glucose in batch fermentation, an improvement of ~67 % over the parental strain (~12.6 g/L). Comparative genomic analysis revealed a single-base deletion in the cac3319 gene leading to C-terminal truncation in its encoding histidine kinase (HK) in JB200. To study the effects of cac3319 mutation on cell growth and fermentation, the cac3319 gene in ATCC 55025 was disrupted using the ClosTron group II intron-based gene inactivation system. Compared to ATCC 55025, the cac3319 HK knockout mutant, HKKO, produced 44.4 % more butanol (18.2 ± 1.3 vs. 12.6 ± 0.2 g/L) with a 90 % higher productivity (0.38 ± 0.03 vs. 0.20 ± 0.02 g/L h) due to increased butanol tolerance, confirming, for the first time, that cac3319 plays an important role in regulating solvent production and tolerance in C. acetobutylicum. This work also provides a novel metabolic engineering strategy for generating high-butanol-tolerant and high-butanol-producing strains for industrial applications.

  3. alpha7 Nicotinic acetylcholine receptor knockout selectively enhances ethanol-, but not beta-amyloid-induced neurotoxicity.

    Science.gov (United States)

    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.

  4. Comprehensive reanalysis of transcription factor knockout expression data in Saccharomyces cerevisiae reveals many new targets.

    Science.gov (United States)

    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.

  5. 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

    2014-11-01

    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.

  6. Generation of knockout rats with X-linked severe combined immunodeficiency (X-SCID using zinc-finger nucleases.

    Directory of Open Access Journals (Sweden)

    Tomoji Mashimo

    Full Text Available BACKGROUND: Although the rat is extensively used as a laboratory model, the inability to utilize germ line-competent rat embryonic stem (ES cells has been a major drawback for studies that aim to elucidate gene functions. Recently, zinc-finger nucleases (ZFNs were successfully used to create genome-specific double-stranded breaks and thereby induce targeted gene mutations in a wide variety of organisms including plants, drosophila, zebrafish, etc. METHODOLOGY/PRINCIPAL FINDINGS: We report here on ZFN-induced gene targeting of the rat interleukin 2 receptor gamma (Il2rg locus, where orthologous human and mouse mutations cause X-linked severe combined immune deficiency (X-SCID. Co-injection of mRNAs encoding custom-designed ZFNs into the pronucleus of fertilized oocytes yielded genetically modified offspring at rates greater than 20%, which possessed a wide variety of deletion/insertion mutations. ZFN-modified founders faithfully transmitted their genetic changes to the next generation along with the severe combined immune deficiency phenotype. CONCLUSIONS AND SIGNIFICANCE: The efficient and rapid generation of gene knockout rats shows that using ZFN technology is a new strategy for creating gene-targeted rat models of human diseases. In addition, the X-SCID rats that were established in this study will be valuable in vivo tools for evaluating drug treatment or gene therapy as well as model systems for examining the treatment of xenotransplanted malignancies.

  7. Generation of Knockout Rats with X-Linked Severe Combined Immunodeficiency (X-SCID) Using Zinc-Finger Nucleases

    Science.gov (United States)

    Mashimo, Tomoji; Takizawa, Akiko; Voigt, Birger; Yoshimi, Kazuto; Hiai, Hiroshi; Kuramoto, Takashi; Serikawa, Tadao

    2010-01-01

    Background Although the rat is extensively used as a laboratory model, the inability to utilize germ line-competent rat embryonic stem (ES) cells has been a major drawback for studies that aim to elucidate gene functions. Recently, zinc-finger nucleases (ZFNs) were successfully used to create genome-specific double-stranded breaks and thereby induce targeted gene mutations in a wide variety of organisms including plants, drosophila, zebrafish, etc. Methodology/Principal Findings We report here on ZFN-induced gene targeting of the rat interleukin 2 receptor gamma (Il2rg) locus, where orthologous human and mouse mutations cause X-linked severe combined immune deficiency (X-SCID). Co-injection of mRNAs encoding custom-designed ZFNs into the pronucleus of fertilized oocytes yielded genetically modified offspring at rates greater than 20%, which possessed a wide variety of deletion/insertion mutations. ZFN-modified founders faithfully transmitted their genetic changes to the next generation along with the severe combined immune deficiency phenotype. Conclusions and Significance The efficient and rapid generation of gene knockout rats shows that using ZFN technology is a new strategy for creating gene-targeted rat models of human diseases. In addition, the X-SCID rats that were established in this study will be valuable in vivo tools for evaluating drug treatment or gene therapy as well as model systems for examining the treatment of xenotransplanted malignancies. PMID:20111598

  8. L1CAM基因敲除小鼠的脑局部血流量、ATP含量和蛋白合成率分析%Analysis of focal cerebral blood flow, ATP content and protein sythesis of L1 gene knockout mice

    Institute of Scientific and Technical Information of China (English)

    张玲; Hossmann Alex

    2007-01-01

    目的 对L1细胞黏附分子(L1 cell adhesion molecule,L1CAM)基因敲除(gene knockout,KO)小鼠的各脑区脑局部血流量、ATP含量和蛋白合成率进行分析,探讨L1CAM基因缺失对小鼠脑局部代谢功能有无影响.方法 用放射性自显影方法测定L1 KO小鼠和野生型对照组小鼠大脑局部血流量和蛋白质合成率,用生物荧光影像技术测定两组ATP含量,并将两组数据进行比较.结果 与野生型小鼠相比,L1 KO小鼠局部脑血流量、ATP含量和蛋白质合成率差异均无统计学意义(均P>0.05).结论 L1CAM基因缺失对小鼠脑局部代谢功能无明显影响,提示L1 KO小鼠可作为研究L1CAM在脑缺血中作用的动物模型.

  9. Generation of transient receptor potential vanilloid 6 gene knockout mouse model%瞬时性受体电位通道香草酸受体亚型6基因敲除小鼠模型的建立

    Institute of Scientific and Technical Information of China (English)

    叶添文; 郑晋华; 安静; 郭清河; 陈方经; 陈爱民

    2012-01-01

    目的 建立瞬时性受体电位通道香草酸受体亚型6(Trpv6)基因敲除小鼠模型,为在体研究Trpv6的生物学功能及其与骨代谢关系奠定基础.方法 从Ensembl数据库中获得小鼠Trpv6基因组序列.设计基因敲除策略,构建基因敲除载体pBR322-MK-Trpv6.以电穿孔方法将基因敲除载体导入胚胎多能干细胞(ES细胞),用G418和Ganciclovoir进行正负筛选,获得双抗性克隆.PCR鉴定出正确同源重组的ES细胞克隆.将正确同源重组的ES细胞注射到C57BL/6J小鼠的囊胚中,获得嵌合体小鼠.挑选嵌合率在50%的雄鼠与C57BL/6J小鼠交配,获得的灰鼠经PCR鉴定为杂合子小鼠.杂合子小鼠交配后获得纯合子小鼠.结果 成功构建了打靶载体pBR322-MK-Trpv6.电穿孔后,共获得24个正确同源重组的克隆,同源重组效率为25%.同源重组的克隆经显微注射后,共获得4只嵌合率大于50%的雄鼠.嵌合鼠与C57BL/6J小鼠交配,获得57只来源于ES细胞的灰鼠,PCR鉴定证实其中17只为杂合子小鼠,阳性率为29.8%.杂合子小鼠交配获得纯合子小鼠.经蛋白质印迹分析证实纯合子小鼠无Trpv6蛋白的表达.结论 成功建立了Trpv6基因敲除小鼠模型,其中纯合子小鼠未出现胚胎致死现象.%Objective To create transient receptor potential vanilloid 6 (Trpv6) gene knockout mouse model, so as to pave a way for further research of its biological function and its role in bone metabolism in vivo. Methods Mouse genomic DNA sequence of Trpv6 gene was obtained from Ensembl database. Trpv6 gene knockout vector (pBR322-MK-Trpv6) was constructed. Trpv6 knockout vector was transferred into the embryonic stem (ES) cells by electroporation and screening of both G418 and Ganciclovoir resistant clones were performed routinely. The homologous recombined ES cell clones were identified by PCR. The correct homologously recombined ES cells were microinjected into C57BL/6J mouse blastocysts to obtain chimera

  10. Effect of knockout of α2δ-1 on action potentials in mouse sensory neurons

    Science.gov (United States)

    Margas, Wojciech; Ferron, Laurent; Nieto-Rostro, Manuela; Schwartz, Arnold; Dolphin, Annette C.

    2016-01-01

    Gene deletion of the voltage-gated calcium channel auxiliary subunit α2δ-1 has been shown previously to have a cardiovascular phenotype, and a reduction in mechano- and cold sensitivity, coupled with delayed development of neuropathic allodynia. We have also previously shown that dorsal root ganglion (DRG) neuron calcium channel currents were significantly reduced in α2δ-1 knockout mice. To extend our findings in these sensory neurons, we have examined here the properties of action potentials (APs) in DRG neurons from α2δ-1 knockout mice in comparison to their wild-type (WT) littermates, in order to dissect how the calcium channels that are affected by α2δ-1 knockout are involved in setting the duration of individual APs and their firing frequency. Our main findings are that there is reduced Ca2+ entry on single AP stimulation, particularly in the axon proximal segment, reduced AP duration and reduced firing frequency to a 400 ms stimulation in α2δ-1 knockout neurons, consistent with the expected role of voltage-gated calcium channels in these events. Furthermore, lower intracellular Ca2+ buffering also resulted in reduced AP duration, and a lower frequency of AP firing in WT neurons, mimicking the effect of α2δ-1 knockout. By contrast, we did not obtain any consistent evidence for the involvement of Ca2+-activation of large conductance calcium-activated potassium (BK) and small conductance calcium-activated potassium (SK) channels in these events. In conclusion, the reduced Ca2+ elevation as a result of single AP stimulation is likely to result from the reduced duration of the AP in α2δ-1 knockout sensory neurons. This article is part of the themed issue ‘Evolution brings Ca2+ and ATP together to control life and death’. PMID:27377724

  11. The Expression of TALEN before Fertilization Provides a Rapid Knock-Out Phenotype in Xenopus laevis Founder Embryos.

    Science.gov (United States)

    Miyamoto, Kei; Suzuki, Ken-Ichi T; Suzuki, Miyuki; Sakane, Yuto; Sakuma, Tetsushi; Herberg, Sarah; Simeone, Angela; Simpson, David; Jullien, Jerome; Yamamoto, Takashi; Gurdon, J B

    2015-01-01

    Recent advances in genome editing using programmable nucleases have revolutionized gene targeting in various organisms. Successful gene knock-out has been shown in Xenopus, a widely used model organism, although a system enabling less mosaic knock-out in founder embryos (F0) needs to be explored in order to judge phenotypes in the F0 generation. Here, we injected modified highly active transcription activator-like effector nuclease (TALEN) mRNA to oocytes at the germinal vesicle (GV) stage, followed by in vitro maturation and intracytoplasmic sperm injection, to achieve a full knock-out in F0 embryos. Unlike conventional injection methods to fertilized embryos, the injection of TALEN mRNA into GV oocytes allows expression of nucleases before fertilization, enabling them to work from an earlier stage. Using this procedure, most of developed embryos showed full knock-out phenotypes of the pigmentation gene tyrosinase and/or embryonic lethal gene pax6 in the founder generation. In addition, our method permitted a large 1 kb deletion. Thus, we describe nearly complete gene knock-out phenotypes in Xenopus laevis F0 embryos. The presented method will help to accelerate the production of knock-out frogs since we can bypass an extra generation of about 1 year in Xenopus laevis. Meantime, our method provides a unique opportunity to rapidly test the developmental effects of disrupting those genes that do not permit growth to an adult able to reproduce. In addition, the protocol shown here is considerably less invasive than the previously used host transfer since our protocol does not require surgery. The experimental scheme presented is potentially applicable to other organisms such as mammals and fish to resolve common issues of mosaicism in founders.

  12. The Expression of TALEN before Fertilization Provides a Rapid Knock-Out Phenotype in Xenopus laevis Founder Embryos.

    Directory of Open Access Journals (Sweden)

    Kei Miyamoto

    Full Text Available Recent advances in genome editing using programmable nucleases have revolutionized gene targeting in various organisms. Successful gene knock-out has been shown in Xenopus, a widely used model organism, although a system enabling less mosaic knock-out in founder embryos (F0 needs to be explored in order to judge phenotypes in the F0 generation. Here, we injected modified highly active transcription activator-like effector nuclease (TALEN mRNA to oocytes at the germinal vesicle (GV stage, followed by in vitro maturation and intracytoplasmic sperm injection, to achieve a full knock-out in F0 embryos. Unlike conventional injection methods to fertilized embryos, the injection of TALEN mRNA into GV oocytes allows expression of nucleases before fertilization, enabling them to work from an earlier stage. Using this procedure, most of developed embryos showed full knock-out phenotypes of the pigmentation gene tyrosinase and/or embryonic lethal gene pax6 in the founder generation. In addition, our method permitted a large 1 kb deletion. Thus, we describe nearly complete gene knock-out phenotypes in Xenopus laevis F0 embryos. The presented method will help to accelerate the production of knock-out frogs since we can bypass an extra generation of about 1 year in Xenopus laevis. Meantime, our method provides a unique opportunity to rapidly test the developmental effects of disrupting those genes that do not permit growth to an adult able to reproduce. In addition, the protocol shown here is considerably less invasive than the previously used host transfer since our protocol does not require surgery. The experimental scheme presented is potentially applicable to other organisms such as mammals and fish to resolve common issues of mosaicism in founders.

  13. Leader genes in osteogenesis: a theoretical study.

    Science.gov (United States)

    Orlando, Bruno; Giacomelli, Luca; Ricci, Massimiliano; Barone, Antonio; Covani, Ugo

    2013-01-01

    Little is still known about the molecular mechanisms involved in the process of osteogenesis. In this paper, the leader genes approach, a new bioinformatics method which has already been experimentally validated, is adopted in order to identify the genes involved in human osteogenesis. Interactions among genes are then calculated and genes are ranked according to their relative importance in this process. In total, 167 genes were identified as being involved in osteogenesis. Genes were divided into 4 groups, according to their main function in the osteogenic processes: skeletal development; cell adhesion and proliferation; ossification; and calcium ion binding. Seven genes were consistently identified as leader genes (i.e. the genes with the greatest importance in osteogenesis), while 14 were found to have slightly less importance (class B genes). It was interesting to notice that the larger part of leader and class B genes belonged to the cell adhesion and proliferation or to the ossification sub-groups. This finding suggested that these two particular sub-processes could play a more important role in osteogenesis. Moreover, among the 7 leader genes, it is interesting to notice that RUNX2, BMP2, SPARC, PTH play a direct role in bone formation, while the 3 other leader genes (VEGF, IL6, FGF2) seem to be more connected with an angiogenetic process. Twenty-nine genes have no known interactions (orphan genes). From these results, it may be possible to plan an ad hoc experimentation, for instance by microarray analyses, focused on leader, class B and orphan genes, with the aim to shed new light on the molecular mechanisms underlying osteogenesis.

  14. The Influence of Knockout ofmenA Gene inEscherichia coli onthe Accumulation of CoQ%大肠杆菌menA敲除对CoQ积累的影响研究

    Institute of Scientific and Technical Information of China (English)

    刘永青; 任琳; 张子锋

    2015-01-01

    通过同源重组敲除大肠杆菌的menA基因,增加菌体CoQ合成量,用于构建CoQ高产菌株。以pKD4质粒为模板, PCR扩增kanr片段;在pKD46的辅助下,kanr片段转化大肠杆菌,利用抗生素筛选和PCR验证重组子;以紫外诱变菌为对照,发酵menA基因敲除菌株,分析CoQ种类和产量变化。成功获得menA基因敲除菌株,CoQ种类不变,产量增加约为38%。首次敲除menA基因,改良株CoQ产量得到提高,达到预期目标。%Knocking outmenA gene of Escherichia coli by homologous recombination increases the synthetized amount of CoQ, which is used for constructing the strains of high-yield CoQ. Using pKD4 plasmid as template, thekanr fragments were amplified by PCR. In the presence of auxiliary plasmid pKD46, thekanr fragments were transformed intoEscherichia coli, and the recombinant one was confirmed by antibiotic screening and verification of PCR;By contrast with uv-induced mutation, the strains withmenA gene knocked out were fermented, and the types of CoQ and the changes of CoQ yield were analyzed. The results showed that thestrains withmenAgeneknockout were successfully obtained, while the types of CoQ unchanged and the yield increased about 38%. In conclusion, this is the first time of knocking outmenA gene, CoQ production of mutant strains is improved, and the desired goal is achieved, which lays a foundation for the further construction of high-yield CoQ strains.

  15. Brain penetration of ivermectin and selamectin in mdr1a,b P-glycoprotein- and bcrp- deficient knockout mice.

    Science.gov (United States)

    Geyer, J; Gavrilova, O; Petzinger, E

    2009-02-01

    P-glycoprotein, which is encoded by the multi-drug resistance gene (MDR1), highly restricts the entry of ivermectin into the brain by an ATP-driven efflux mechanism at the blood-brain barrier. In dogs with a homozygous MDR1 mutation though, ivermectin accumulates in the brain and provokes severe signs of neurotoxicosis and even death. In contrast to ivermectin, selamectin is safer in the treatment of MDR1 mutant dogs, suggesting that selamectin is transported differently by P-glycoprotein across the blood-brain barrier. To test this, we applied selamectin to mdr1-deficient mdr1a,b(-/-) knockout mice and wild-type mice. Brain penetration, organ distribution, and plasma kinetics were analyzed after intravenous, oral, and dermal spot-on application in comparison with ivermectin. We found that in vivo both macrocyclic lactone compounds are substrates of P-glycoprotein and that these strongly accumulate in the brain of mdr1a,b(-/-) knockout mice compared with wild-type mice at therapeutic doses of 12 mg/kg selamectin and 0.2 mg/kg ivermectin. However, selamectin accumulates to a much lesser degree (5-10 times) than ivermectin (36-60 times) in the absence of P-glycoprotein. This could explain the broader margin of safety of selamectin in MDR1 mutant dogs. In liver, kidney, and testes, ivermectin and selamectin accumulated less than four times as much in mdr1a,b mutant mice as in wild-type mice. Breast cancer resistance protein (Bcrp)-deficient bcrp(-/-) knockout mice were also included in the application studies, but showed no differences in brain concentrations or organ distribution of either ivermectin or selamectin compared with wild-type mice. This indicates that Bcrp is not a relevant efflux carrier for these macrocyclic lactone compounds in vivo at the blood-brain barrier.

  16. 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.

  17. Neuron-specific (pro)renin receptor knockout prevents the development of salt-sensitive hypertension.

    Science.gov (United States)

    Li, Wencheng; Peng, Hua; Mehaffey, Eamonn P; Kimball, Christie D; Grobe, Justin L; van Gool, Jeanette M G; Sullivan, Michelle N; Earley, Scott; Danser, A H Jan; Ichihara, Atsuhiro; Feng, Yumei

    2014-02-01

    The (pro)renin receptor (PRR), which binds both renin and prorenin, is a newly discovered component of the renin-angiotensin system that is highly expressed in the central nervous system. The significance of brain PRRs in mediating local angiotensin II formation and regulating blood pressure remains unclear. The current study was performed to test the hypothesis that PRR-mediated, nonproteolytic activation of prorenin is the main source of angiotensin II in the brain. Thus, PRR knockout in the brain is expected to prevent angiotensin II formation and development of deoxycorticosterone acetate-salt-induced hypertension. A neuron-specific PRR (ATP6AP2) knockout mouse model was generated using the Cre-LoxP system. Physiological parameters were recorded by telemetry. PRR expression, detected by immunostaining and reverse transcription-polymerase chain reaction, was significantly decreased in the brains of knockout mice compared with wild-type mice. Intracerebroventricular infusion of mouse prorenin increased blood pressure and angiotensin II formation in wild-type mice. This hypertensive response was abolished in PRR-knockout mice in association with a reduction in angiotensin II levels. Deoxycorticosterone acetate-salt increased PRR expression and angiotensin II formation in the brains of wild-type mice, an effect that was attenuated in PRR-knockout mice. PRR knockout in neurons prevented the development of deoxycorticosterone acetate-salt-induced hypertension as well as activation of cardiac and vasomotor sympathetic tone. In conclusion, nonproteolytic activation of prorenin through binding to the PRR mediates angiotensin II formation in the brain. Neuron-specific PRR knockout prevents the development of deoxycorticosterone acetate-salt-induced hypertension, possibly through diminished angiotensin II formation.

  18. Attenuated defense response and low basal blood pressure in orexin knockout mice.

    Science.gov (United States)

    Kayaba, Yuji; Nakamura, Akira; Kasuya, Yoshitoshi; Ohuchi, Takashi; Yanagisawa, Masashi; Komuro, Issei; Fukuda, Yasuichiro; Kuwaki, Tomoyuki

    2003-09-01

    The perifornical area of the hypothalamus has been known as the center for the defense response, or "fight or flight" response, which is characterized by a concomitant rise in arterial blood pressure (AP), heart rate (HR), and respiratory frequency (Rf). We examined whether orexin, a recently identified hypothalamic neuropeptide, contributes to the defense response and basal cardiovascular regulation using orexin knockout mice. Microinjection of a GABA-A receptor antagonist, bicuculline methiodide (0.1-1 mM in 20 nl), to the perifornical area in urethane-anesthetized wild-type mice elicited dose-dependent increases in AP, HR, and Rf. Although similar changes were observed in orexin knockout mice, intensities were smaller and duration was shorter than those in wild-type mice. Moreover, in an awake and freely moving condition, telemeter-indwelling orexin knockout mice showed diminished cardiovascular and behavioral responses to emotional stress in the resident-intruder test. We also found that basal AP in orexin knockout mice was significantly lower in both anesthetized (117 +/- 8 mmHg in wild type and 92 +/- 3 in knockout) and conscious (125 +/- 6 mmHg in wild type and 109 +/- 2 in knockout) conditions. alpha-Adrenergic blockade with prazosin or ganglion blockade with hexamethonium canceled the difference in basal AP. HR and cardiac contractile parameters by echocardiography did not differ between the two strains of mice. These results indicate lower sympathetic vasoconstrictor tone in knockout mice. The present study suggests that orexin-containing neurons in the perifornical area play a role as one of the efferent pathways of defense response and also operate as a regulator of AP at basal condition by activating sympathetic outflow.

  19. PON3 knockout mice are susceptible to obesity, gallstone formation, and atherosclerosis

    Science.gov (United States)

    Shih, Diana M.; Yu, Janet M.; Vergnes, Laurent; Dali-Youcef, Nassim; Champion, Matthew D.; Devarajan, Asokan; Zhang, Peixiang; Castellani, Lawrence W.; Brindley, David N.; Jamey, Carole; Auwerx, Johan; Reddy, Srinivasa T.; Ford, David A.; Reue, Karen; Lusis, Aldons J.

    2015-01-01

    We report the engineering and characterization of paraoxonase-3 knockout mice (Pon3KO). The mice were generally healthy but exhibited quantitative alterations in bile acid metabolism and a 37% increased body weight compared to the wild-type mice on a high fat diet. PON3 was enriched in the mitochondria-associated membrane fraction of hepatocytes. PON3 deficiency resulted in impaired mitochondrial respiration, increased mitochondrial superoxide levels, and increased hepatic expression of inflammatory genes. PON3 deficiency did not influence atherosclerosis development on an apolipoprotein E null hyperlipidemic background, but it did lead to a significant 60% increase in atherosclerotic lesion size in Pon3KO mice on the C57BL/6J background when fed a cholate-cholesterol diet. On the diet, the Pon3KO had significantly increased plasma intermediate-density lipoprotein/LDL cholesterol and bile acid levels. They also exhibited significantly elevated levels of hepatotoxicity markers in circulation, a 58% increase in gallstone weight, a 40% increase in hepatic cholesterol level, and increased mortality. Furthermore, Pon3KO mice exhibited decreased hepatic bile acid synthesis and decreased bile acid levels in the small intestine compared with wild-type mice. Our study suggests a role for PON3 in the metabolism of lipid and bile acid as well as protection against atherosclerosis, gallstone disease, and obesity.—Shih, D. M., Yu, J. M., Vergnes, L., Dali-Youcef, N., Champion, M. D., Devarajan, A., Zhang, P., Castellani, L. W., Brindley, D. N., Jamey, C. Auwerx, J., Reddy, S. T., Ford, D. A., Reue, K., Lusis, A. J. PON3 knockout mice are susceptible to obesity, gallstone formation, and atherosclerosis. PMID:25477283

  20. Analysis of knockout mutants reveals non-redundant functions of poly(ADP-ribose)polymerase isoforms in Arabidopsis.

    Science.gov (United States)

    Pham, Phuong Anh; Wahl, Vanessa; Tohge, Takayuki; de Souza, Laise Rosado; Zhang, Youjun; Do, Phuc Thi; Olas, Justyna J; Stitt, Mark; Araújo, Wagner L; Fernie, Alisdair R

    2015-11-01

    The enzyme poly(ADP-ribose)polymerase (PARP) has a dual function being involved both in the poly(ADP-ribosyl)ation and being a constituent of the NAD(+) salvage pathway. To date most studies, both in plant and non-plant systems, have focused on the signaling role of PARP in poly(ADP-ribosyl)ation rather than any role that can be ascribed to its metabolic function. In order to address this question we here used a combination of expression, transcript and protein localization studies of all three PARP isoforms of Arabidopsis alongside physiological analysis of the corresponding mutants. Our analyses indicated that whilst all isoforms of PARP were localized to the nucleus they are also present in non-nuclear locations with parp1 and parp3 also localised in the cytosol, and parp2 also present in the mitochondria. We next isolated and characterized insertional knockout mutants of all three isoforms confirming a complete knockout in the full length transcript levels of the target genes as well as a reduced total leaf NAD hydrolase activity in the two isoforms (PARP1, PARP2) that are highly expressed in leaves. Physiological evaluation of the mutant lines revealed that they displayed distinctive metabolic and root growth characteristics albeit unaltered leaf morphology under optimal growth conditions. We therefore conclude that the PARP isoforms play non-redundant non-nuclear metabolic roles and that their function is highly important in rapidly growing tissues such as the shoot apical meristem, roots and seeds.

  1. Identification of Hematopoietic Stem Cell Engraftment Genes in Gene Therapy Studies.

    Science.gov (United States)

    Powers, John M; Trobridge, Grant D

    2013-09-01

    Hematopoietic stem cell (HSC) therapy using replication-incompetent retroviral vectors is a promising approach to provide life-long correction for genetic defects. HSC gene therapy clinical studies have resulted in functional cures for several diseases, but in some studies clonal expansion or leukemia has occurred. This is due to the dyregulation of endogenous host gene expression from vector provirus insertional mutagenesis. Insertional mutagenesis screens using replicating retroviruses have been used extensively to identify genes that influence oncogenesis. However, retroviral mutagenesis screens can also be used to determine the role of genes in biological processes such as stem cell engraftment. The aim of this review is to describe the potential for vector insertion site data from gene therapy studies to provide novel insights into mechanisms of HSC engraftment. In HSC gene therapy studies dysregulation of host genes by replication-incompetent vector proviruses may lead to enrichment of repopulating clones with vector integrants near genes that influence engraftment. Thus, data from HSC gene therapy studies can be used to identify novel candidate engraftment genes. As HSC gene therapy use continues to expand, the vector insertion site data collected will be of great interest to help identify novel engraftment genes and may ultimately lead to new therapies to improve engraftment.

  2. Identification of Human HK Genes and Gene Expression Regulation Study in Cancer from Transcriptomics Data Analysis

    Science.gov (United States)

    Zhang, Zhang; Liu, Jingxing; Wu, Jiayan; Yu, Jun

    2013-01-01

    The regulation of gene expression is essential for eukaryotes, as it drives the processes of cellular differentiation and morphogenesis, leading to the creation of different cell types in multicellular organisms. RNA-Sequencing (RNA-Seq) provides researchers with a powerful toolbox for characterization and quantification of transcriptome. Many different human tissue/cell transcriptome datasets coming from RNA-Seq technology are available on public data resource. The fundamental issue here is how to develop an effective analysis method to estimate expression pattern similarities between different tumor tissues and their corresponding normal tissues. We define the gene expression pattern from three directions: 1) expression breadth, which reflects gene expression on/off status, and mainly concerns ubiquitously expressed genes; 2) low/high or constant/variable expression genes, based on gene expression level and variation; and 3) the regulation of gene expression at the gene structure level. The cluster analysis indicates that gene expression pattern is higher related to physiological condition rather than tissue spatial distance. Two sets of human housekeeping (HK) genes are defined according to cell/tissue types, respectively. To characterize the gene expression pattern in gene expression level and variation, we firstly apply improved K-means algorithm and a gene expression variance model. We find that cancer-associated HK genes (a HK gene is specific in cancer group, while not in normal group) are expressed higher and more variable in cancer condition than in normal condition. Cancer-associated HK genes prefer to AT-rich genes, and they are enriched in cell cycle regulation related functions and constitute some cancer signatures. The expression of large genes is also avoided in cancer group. These studies will help us understand which cell type-specific patterns of gene expression differ among different cell types, and particularly for cancer. PMID:23382867

  3. Knockout of Vasohibin-1 Gene in Mice Results in Healthy Longevity with Reduced Expression of Insulin Receptor, Insulin Receptor Substrate 1, and Insulin Receptor Substrate 2 in Their White Adipose Tissue

    Science.gov (United States)

    Takeda, Eichi; Suzuki, Yasuhiro; Yamada, Tetsuya; Katagiri, Hideki

    2017-01-01

    Vasohibin-1 (Vash1), originally isolated as an endothelium-derived angiogenesis inhibitor, has a characteristic of promoting stress tolerance in endothelial cells (ECs). We therefore speculated that the lack of the vash1 gene would result in a short lifespan. However, to our surprise, vash1−/− mice lived significantly longer with a milder senescence phenotype than wild-type (WT) mice. We sought the cause of this healthy longevity and found that vash1−/− mice exhibited mild insulin resistance along with reduced expression of the insulin receptor (insr), insulin receptor substrate 1 (irs-1), and insulin receptor substrate 2 (irs-2) in their white adipose tissue (WAT) but not in their liver or skeletal muscle. The expression of vash1 dominated in the WAT among those 3 organs. Importantly, vash1−/− mice did not develop diabetes even when fed a high-fat diet. These results indicate that the expression of vash1 was required for the normal insulin sensitivity of the WAT and that the target molecules for this activity were insr, irs1, and irs2. The lack of vash1 caused mild insulin resistance without the outbreak of overt diabetes and might contribute to healthy longevity.

  4. Knockout of Vasohibin-1 Gene in Mice Results in Healthy Longevity with Reduced Expression of Insulin Receptor, Insulin Receptor Substrate 1, and Insulin Receptor Substrate 2 in Their White Adipose Tissue

    Directory of Open Access Journals (Sweden)

    Eichi Takeda

    2017-01-01

    Full Text Available Vasohibin-1 (Vash1, originally isolated as an endothelium-derived angiogenesis inhibitor, has a characteristic of promoting stress tolerance in endothelial cells (ECs. We therefore speculated that the lack of the vash1 gene would result in a short lifespan. However, to our surprise, vash1−/− mice lived significantly longer with a milder senescence phenotype than wild-type (WT mice. We sought the cause of this healthy longevity and found that vash1−/− mice exhibited mild insulin resistance along with reduced expression of the insulin receptor (insr, insulin receptor substrate 1 (irs-1, and insulin receptor substrate 2 (irs-2 in their white adipose tissue (WAT but not in their liver or skeletal muscle. The expression of vash1 dominated in the WAT among those 3 organs. Importantly, vash1−/− mice did not develop diabetes even when fed a high-fat diet. These results indicate that the expression of vash1 was required for the normal insulin sensitivity of the WAT and that the target molecules for this activity were insr, irs1, and irs2. The lack of vash1 caused mild insulin resistance without the outbreak of overt diabetes and might contribute to healthy longevity.

  5. 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.

  6. 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

  7. Studying the Complex Expression Dependences between Sets of Coexpressed Genes

    Directory of Open Access Journals (Sweden)

    Mario Huerta

    2014-01-01

    Full Text Available Organisms simplify the orchestration of gene expression by coregulating genes whose products function together in the cell. The use of clustering methods to obtain sets of coexpressed genes from expression arrays is very common; nevertheless there are no appropriate tools to study the expression networks among these sets of coexpressed genes. The aim of the developed tools is to allow studying the complex expression dependences that exist between sets of coexpressed genes. For this purpose, we start detecting the nonlinear expression relationships between pairs of genes, plus the coexpressed genes. Next, we form networks among sets of coexpressed genes that maintain nonlinear expression dependences between all of them. The expression relationship between the sets of coexpressed genes is defined by the expression relationship between the skeletons of these sets, where this skeleton represents the coexpressed genes with a well-defined nonlinear expression relationship with the skeleton of the other sets. As a result, we can study the nonlinear expression relationships between a target gene and other sets of coexpressed genes, or start the study from the skeleton of the sets, to study the complex relationships of activation and deactivation between the sets of coexpressed genes that carry out the different cellular processes present in the expression experiments.

  8. Liver steatosis study_PFAA treated mouse gene array data

    Data.gov (United States)

    U.S. Environmental Protection Agency — This file contains a link for Gene Expression Omnibus and the GSE designations for the publicly available gene expression data used in the study and reflected in...

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

    Directory of Open Access Journals (Sweden)

    Matyas Flemr

    2015-07-01

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

  10. Two Proton Knockout from ^32Mg

    Science.gov (United States)

    Fallon, P.; Rodriguez-Vieitez, E.; Macchiavelli, A. O.; Clark, R. M.; Lee, I.-Y.; Wiedeking, M.; Gade, A.; Adrich, P.; Bazin, D.; Bowen, M.; Campbell, C. M.; Cook, J. M.; Dinca, D. C.; Glasmacher, T.; McDaniel, S.; Mueller, W. F.; Ratiewicz, A. F.; Siwek, K.; Terry, J. R.; Wiesshaar, D.; Yoneda, K.; Brown, B. A.; Otsuka, T.; Tostevin, J. A.; Utsuno, Y.

    2009-05-01

    We present data and calculations on the near-dripline nucleus ^30Ne. Gamma-ray decays from excited states as well as inclusive and exclusive cross-sections were measured in the ^9Be(^32Mg,^30Ne γ)X two-proton knockout reaction at incident beam energies of 99.7 and 86.7 MeV/A. The measured inclusive cross section sigma = 0.22(4)mb is suppressed compared to calculation and is indicative of a reduced overlap of initial and final state wavefunctions. We interpret this reduction as a result of large 4p4h intruder components present in ^30Ne, but not ^32Mg. Large 4p4h amplitudes are predicted to generate increased T=1 paring strengths and to help stabilize the heavier fluorine isotopes against neutron decay. A new gamma-ray transition at 1443 keV is assigned to the decay of the 4^+ state based on the spin dependent sigma for 2 proton knockout from the (d5/2)^4 configuration.

  11. Maltodextrin and fat preference deficits in "taste-blind" P2X2/P2X3 knockout mice.

    Science.gov (United States)

    Sclafani, Anthony; Ackroff, Karen

    2014-07-01

    Adenosine triphosphate is a critical neurotransmitter in the gustatory response to the 5 primary tastes in mice. Genetic deletion of the purinergic P2X2/P2X3 receptor greatly reduces the neural and behavioral response to prototypical primary taste stimuli. In this study, we examined the behavioral response of P2X double knockout mice to maltodextrin and fat stimuli, which appear to activate additional taste channels. P2X double knockout and wild-type mice were given 24-h choice tests (vs. water) with ascending concentrations of Polycose and Intralipid. In Experiment 1, naive double knockout mice, unlike wild-type mice, were indifferent to dilute (0.5-4%) Polycose solutions but preferred concentrated (8-32%) Polycose to water. In a retest, the Polycose-experienced double knockout mice, like wild-type mice, preferred all Polycose concentrations. In Experiment 2, naive double knockout mice, unlike wild-type mice, were indifferent to dilute (0.313-2.5%) Intralipid emulsions but preferred concentrated (5-20%) Intralipid to water. In a retest, the fat-experienced double knockout mice, like wild-type mice, strongly preferred 0.313-5% Intralipid to water. These results indicate that the inherent preferences of mice for maltodextrin and fat are dependent upon adenosine triphosphate taste cell signaling. With experience, however, P2X double knockout mice develop strong preferences for the nontaste flavor qualities of maltodextrin and fat conditioned by the postoral actions of these nutrients.

  12. Dopamine D(2) receptor function is compromised in the brain of the methionine sulfoxide reductase A knockout mouse.

    Science.gov (United States)

    Oien, Derek B; Ortiz, Andrea N; Rittel, Alexander G; Dobrowsky, Rick T; Johnson, Michael A; Levant, Beth; Fowler, Stephen C; Moskovitz, Jackob

    2010-07-01

    Previous research suggests that brain oxidative stress and altered rodent locomotor behavior are linked. We observed bio-behavioral changes in methionine sulfoxide reductase A knockout mice associated with abnormal dopamine signaling. Compromised ability of these knockout mice to reduce methionine sulfoxide enhances accumulation of sulfoxides in proteins. We examined the dopamine D(2)-receptor function and expression, which has an atypical arrangement and quantity of methionine residues. Indeed, protein expression levels of dopamine D(2)-receptor were higher in knockout mice compared with wild-type. However, the binding of dopamine D(2)-receptor agonist was compromised in the same fractions of knockout mice. Coupling efficiency of dopamine D(2)-receptors to G-proteins was also significantly reduced in knockout mice, supporting the compromised agonist binding. Furthermore, pre-synaptic dopamine release in knockout striatal sections was less responsive than control sections to dopamine D(2)-receptor ligands. Behaviorally, the locomotor activity of knockout mice was less responsive to the inhibitory effect of quinpirole than wild-type mice. Involvement of specific methionine residue oxidation in the dopamine D(2)-receptor third intracellular loop is suggested by in vitro studies. We conclude that ablation of methionine sulfoxide reductase can affect dopamine signaling through altering dopamine D(2)-receptor physiology and may be related to symptoms associated with neurological disorders and diseases.

  13. Dopamine D2 receptor function is compromised in the brain of the methionine sulfoxide reductase A knockout mouse

    Science.gov (United States)

    Oien, Derek B.; Ortiz, Andrea N.; Rittel, Alexander G.; Dobrowsky, Rick T.; Johnson, Michael A.; Levant, Beth; Fowler, Stephen C.; Moskovitz, Jackob

    2010-01-01

    Previous research suggests that brain oxidative stress and altered rodent locomotor behavior are linked. We observed bio-behavioral changes in methionine sulfoxide reductase A knockout mice associated with abnormal dopamine signaling. Compromised ability of these knockout mice to reduce methionine sulfoxide enhances accumulation of sulfoxides in proteins. We examined the dopamine D2-receptor function and expression, which has an atypical arrangement and quantity of methionine residues. Indeed, protein expression levels of dopamine D2-receptor were higher in knockout mice compared with wild-type. However, the binding of dopamine D2-receptor agonist was compromised in the same fractions of knockout mice. Coupling efficiency of dopamine D2-receptors to G-proteins was also significantly reduced in knockout mice, supporting the compromised agonist binding. Furthermore, pre-synaptic dopamine release in knockout striatal sections was less responsive than control sections to dopamine D2-receptor ligands. Behaviorally, the locomotor activity of knockout mice was less responsive to the inhibitory effect of quinpirole than wild-type mice. Involvement of specific methionine residue oxidation in the dopamine D2-receptor third intracellular loop is suggested by in vitro studies. We conclude that ablation of methionine sulfoxide reductase can affect dopamine signaling through altering dopamine D2-receptor physiology and may be related to symptoms associated with neurological disorders and diseases. PMID:20374422

  14. Tendon fascicle gliding in wild type, heterozygous, and lubricin knockout mice.

    Science.gov (United States)

    Kohrs, Ross T; Zhao, Chunfeng; Sun, Yu-Long; Jay, Gregory D; Zhang, Ling; Warman, Matthew L; An, Kai-Nan; Amadio, Peter C

    2011-03-01

    The objective of this study was to investigate the role of lubricin in the lubrication of tendon fascicles. Lubricin, a glycoprotein, lubricates cartilage and tendon surfaces, but the function of lubricin within the tendon fascicle is unclear. We developed a novel method to assess the gliding resistance of a single fascicle in a mouse tail model and used it to test the hypothesis that gliding resistance would be increased in lubricin knockout mice. Thirty-six mouse tails were used from 12 wild type, 12 heterozygous, and 12 lubricin knockout mice. A 15 mm long fascicle segment was pulled proximally after being divided distally. The peak resistance during fascicle pullout and the fascicle perimeter were measured. Lubricin expression was evaluated by immunohistochemistry. The peak gliding resistance in the lubricin knockout mice was significantly higher than in the wild type (p < 0.05). Fascicles from heterozygous mice were intermediate in value, but not significantly different from either wild type or lubricin knockout fascicles in peak gliding resistance. No significant difference was found in fascicle perimeter among the three groups. No correlation was observed between fascicle perimeter and gliding resistance. While lubricin was detected by immunostaining on the fascicle surface in wild type and heterozygous mice, lubricin was not detectable in the tendons of knockout mice. We conclude that the absence of lubricin is associated with increased interfascicular friction and that lubricin may play an important role in interfascicular lubrication.

  15. 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.

  16. Creatine transporter (CrT; Slc6a8 knockout mice as a model of human CrT deficiency.

    Directory of Open Access Journals (Sweden)

    Matthew R Skelton

    Full Text Available Mutations in the creatine (Cr transporter (CrT; Slc6a8 gene lead to absence of brain Cr and intellectual disabilities, loss of speech, and behavioral abnormalities. To date, no mouse model of CrT deficiency exists in which to understand and develop treatments for this condition. The purpose of this study was to generate a mouse model of human CrT deficiency. We created mice with exons 2-4 of Slc6a8 flanked by loxP sites and crossed these to Cre:CMV mice to create a line of ubiquitous CrT knockout expressing mice. Mice were tested for learning and memory deficits and assayed for Cr and neurotransmitter levels. Male CrT(⁻/y (affected mice lack Cr in the brain and muscle with significant reductions of Cr in other tissues including heart and testes. CrT(⁻/y mice showed increased path length during acquisition and reversal learning in the Morris water maze. During probe trials, CrT(⁻/y mice showed increased average distance from the platform site. CrT(⁻/y mice showed reduced novel object recognition and conditioned fear memory compared to CrT(+/y. CrT(⁻/y mice had increased serotonin and 5-hydroxyindole acetic acid in the hippocampus and prefrontal cortex. Ubiquitous CrT knockout mice have learning and memory deficits resembling human CrT deficiency and this model should be useful in understanding this disorder.

  17. SMB myosin heavy chain knockout enhances tonic contraction and reduces the rate of force generation in ileum and stomach antrum.

    Science.gov (United States)

    Huang, Qian; Babu, Gopal J; Periasamy, Muthu; Eddinger, Thomas J

    2013-01-15

    The role of SMA and SMB smooth muscle myosin heavy chain (MHC) isoforms in tonic and phasic contractions was studied in phasic (longitudinal ileum and stomach circular antrum) and tonic (stomach circular fundus) smooth muscle tissues of SMB knockout mice. Knocking out the SMB MHC gene eliminated SMB MHC protein expression and resulted in upregulation of the SMA MHC protein without altering the total MHC protein level. Switching from SMB to SMA MHC protein expression decreased the rate of the force transient and increased the sustained tonic force in SMB((-/-)) ileum and antrum with high potassium (KPSS) but not with carbachol (CCh) stimulation. The increased tonic contraction under the depolarized condition was not through changes in second messenger signaling pathways (PKC/CPI-17 or Rho/ROCK signaling pathway) or LC(20) phosphorylation. Biochemical analyses showed that the expression of contractile regulatory proteins (MLCK, MLCP, PKCδ, and CPI-17) did not change significantly in tissues tested except for PKCα protein expression being significantly decreased in the SMB((-/-)) antrum. However, specifically activating PKCα with phorbol dibutyrate (PDBu) was not significantly different in knockout and wild-type tissues, with total force being a fraction of the force generation with KPSS or CCh stimulation in SMB((-/-)) ileum and antrum. Taken together, these data show removing the SMB MHC protein expression with a compensatory increase in the SMA MHC protein results in enhanced sustained KPSS-induced tonic contraction with a reduced rate of force generation in these phasic tissues.

  18. 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.

  19. Role of CCK-A receptor in the regulation of pancreatic bicarbonate secretion in conscious rats: a study in naturally occurring CCK-A receptor gene knockout rats.

    Science.gov (United States)

    Miyasaka, K; Suzuki, S; Kanai, S; Masuda, M; Funakoshi, A

    1999-10-01

    Whether cholecystokinin (CCK) has a direct action on duct cells and the role of CCK-A receptor in bicarbonate secretion were examined by comparing the results obtained from OLETF (CCK-A receptor-deficient rats) and control (LETO) rats. Rats were prepared with cannulae for draining bile and pancreatic juice separately, with two duodenal cannulae and an external jugular vein cannula. The experiments were conducted without anesthesia. The responses of bicarbonate secretion to intravenous infusion of CCK, acetyl-beta-methylcholine (Ach), and 2-deoxy-D-glucose (2DG), and to intraduodenal infusion of HCl and a liquid meal were examined. To examine the synergistic effect between CCK and secretin, the effect of CCK during a background secretin infusion was examined in LETO rats. CCK did not stimulate bicarbonate secretion in either strain, nor in LETO rats with secretin infusion. When gastric acid secretion was prevented by administration of omeprazole, Ach did not increase bicarbonate secretion, but 2DG did in both strains. Intraduodenal infusion of HCI and a liquid meal significantly increased bicarbonate secretion in both strains; however, the responses were much less in OLETF than LETO rats. In conclusion, intravenous injection of CCK did not stimulate bicarbonate secretion, and the lack of CCK-A receptor decreased bicarbonate secretion in response to luminal stimulants.

  20. No evidence for a bone phenotype in GPRC6A knockout mice under normal physiological conditions

    DEFF Research Database (Denmark)

    Wellendorph, Petrine; Johansen, Lars Dan; Jensen, Anders Asbjørn;

    2009-01-01

    . Analogously to the closely related calcium-sensing receptor, GPRC6A has been proposed to function as a metabolic sensor of Ca2+ and amino acids in bone and other tissues. In the present study, we have generated the first GPRC6A knockout mice and studied their phenotype with particular focus on bone...... homeostasis. The generated GPRC6A knockout mice are viable and fertile, develop normally and exhibit no significant differences in body weight compared to wild type littermates. Assessment of bone mineral density, histomorphometry and bone metabolism demonstrated no significant differences between 13-week......-old knockout and wild type mice. In conclusion, our data do not support a role for GPRC6A in normal bone physiology....

  1. Postsynaptic Target Specific Synaptic Dysfunctions in the CA3 Area of BACE1 Knockout Mice

    OpenAIRE

    2014-01-01

    Beta-amyloid precursor protein cleaving enzyme 1 (BACE1), a major neuronal β-secretase critical for the formation of β-amyloid (Aβ) peptide, is considered one of the key therapeutic targets that can prevent the progression of Alzheimer's disease (AD). Although a complete ablation of BACE1 gene prevents Aβ formation, we previously reported that BACE1 knockouts (KOs) display presynaptic deficits, especially at the mossy fiber (MF) to CA3 synapses. Whether the defect is specific to certain input...

  2. Transgenic knockout mice with exclusively human sickle hemoglobinand sickle cell disease

    Energy Technology Data Exchange (ETDEWEB)

    Paszty, C.; Brion, C.; Manci, E.; Witkowska, E.; Stevens, M.; Narla, M.; Rubin, E.

    1997-06-13

    To create mice expressing exclusively human sicklehemoglobin (HbS), transgenic mice expressing human alpha-, gamma-, andbeta[S]-globin were generated and bred with knockout mice that haddeletions of the murine alpha- and beta-globin genes. These sickle cellmice have the major features (irreversibly sickled red cells, anemia,multiorgan pathology) found in humans with sickle cell disease and, assuch, represent a useful in vivo system to accelerate the development ofimproved therapies for this common genetic disease.

  3. 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.

  4. RAG1/2 knockout pigs with severe combined immunodeficiency.

    Science.gov (United States)

    Huang, Jiao; Guo, Xiaogang; Fan, Nana; Song, Jun; Zhao, Bentian; Ouyang, Zhen; Liu, Zhaoming; Zhao, Yu; Yan, Quanmei; Yi, Xiaoling; Schambach, Axel; Frampton, Jon; Esteban, Miguel A; Yang, Dongshan; Yang, Huaqiang; Lai, Liangxue

    2014-08-01

    Pigs share many physiological, biochemical, and anatomical similarities with humans and have emerged as valuable large animal models for biomedical research. Considering the advantages in immune system resemblance, suitable size, and longevity for clinical practical and monitoring purpose, SCID pigs bearing dysfunctional RAG could serve as important experimental tools for regenerative medicine, allograft and xenograft transplantation, and reconstitution experiments related to the immune system. In this study, we report the generation and phenotypic characterization of RAG1 and RAG2 knockout pigs using transcription activator-like effector nucleases. Porcine fetal fibroblasts were genetically engineered using transcription activator-like effector nucleases and then used to provide donor nuclei for somatic cell nuclear transfer. We obtained 27 live cloned piglets; among these piglets, 9 were targeted with biallelic mutations in RAG1, 3 were targeted with biallelic mutations in RAG2, and 10 were targeted with a monoallelic mutation in RAG2. Piglets with biallelic mutations in either RAG1 or RAG2 exhibited hypoplasia of immune organs, failed to perform V(D)J rearrangement, and lost mature B and T cells. These immunodeficient RAG1/2 knockout pigs are promising tools for biomedical and translational research.

  5. Identification and validation of suitable endogenous reference genes for gene expression studies in human peripheral blood

    Directory of Open Access Journals (Sweden)

    Turner Renee J

    2009-08-01

    Full Text Available Abstract Background Gene expression studies require appropriate normalization methods. One such method uses stably expressed reference genes. Since suitable reference genes appear to be unique for each tissue, we have identified an optimal set of the most stably expressed genes in human blood that can be used for normalization. Methods Whole-genome Affymetrix Human 2.0 Plus arrays were examined from 526 samples of males and females ages 2 to 78, including control subjects and patients with Tourette syndrome, stroke, migraine, muscular dystrophy, and autism. The top 100 most stably expressed genes with a broad range of expression levels were identified. To validate the best candidate genes, we performed quantitative RT-PCR on a subset of 10 genes (TRAP1, DECR1, FPGS, FARP1, MAPRE2, PEX16, GINS2, CRY2, CSNK1G2 and A4GALT, 4 commonly employed reference genes (GAPDH, ACTB, B2M and HMBS and PPIB, previously reported to be stably expressed in blood. Expression stability and ranking analysis were performed using GeNorm and NormFinder algorithms. Results Reference genes were ranked based on their expression stability and the minimum number of genes needed for nomalization as calculated using GeNorm showed that the fewest, most stably expressed genes needed for acurate normalization in RNA expression studies of human whole blood is a combination of TRAP1, FPGS, DECR1 and PPIB. We confirmed the ranking of the best candidate control genes by using an alternative algorithm (NormFinder. Conclusion The reference genes identified in this study are stably expressed in whole blood of humans of both genders with multiple disease conditions and ages 2 to 78. Importantly, they also have different functions within cells and thus should be expressed independently of each other. These genes should be useful as normalization genes for microarray and RT-PCR whole blood studies of human physiology, metabolism and disease.

  6. 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

  7. Adaptations in pre- and postsynaptic 5-HT1A receptor function and cocaine supersensitivity in serotonin transporter knockout rats.

    NARCIS (Netherlands)

    Homberg, J.R.; Boer, SF De; Raaso, H.S.; Olivier, J.D.A.; Verheul, M.; Ronken, E.; Cools, A.R.; Ellenbroek, B.A.; Schoffelmeer, A.N.; Schuren, L.J. van der; Vries, TJ De; Cuppen, E.

    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

  8. Association study between genes in Reelin signaling pathway and autism identifies DAB1 as a susceptibility gene in a Chinese Han population.

    Science.gov (United States)

    Li, Jun; Liu, Jing; Zhao, Linnan; Ma, Yuanlin; Jia, Meixiang; Lu, Tianlan; Ruan, Yanyan; Li, Qizhai; Yue, Weihua; Zhang, Dai; Wang, Lifang

    2013-07-01

    Autism is a pervasive neurodevelopmental disorder diagnosed in early childhood. The genetic factors might play an important role in its pathogenesis. Previous studies revealed that Reelin (RELN) polymorphisms were associated with autism. However, the roles of genes in Reelin signaling pathway for autism are largely unknown. As several knockout mice models in which the Reelin pathway genes (i.e. DAB1, VLDLR/APOER2, FYN/SRC and CRK/CRKL) are deficient have the similar phenotype as the reeler mice (Reelin(-/-)), we hypothesized that the Reelin signaling pathway genes might play roles in the etiology of autism. Therefore, we conducted a family-based association study. Sixty-two tagged single nucleotide polymorphisms (SNPs) covering 15 genes in Reelin pathway were genotyped in 239 trios, and 14 significant SNPs were further investigated in the additional 188 trios. In the total 427 trios, we found significant genetic association between autism and four SNPs in DAB1 (rs12035887 G: p=0.0006; rs3738556 G: p=0.0044; rs1202773 A: p=0.0048; rs12740765 T: p=0.0196). After the Bonferroni correction, SNP rs12035887 remained significant. Furthermore, the haplotype constructed with rs1202773 and rs12023109 in DAB1 showed significant excess transmission in both individual and global haplotype analyses (p=0.0052 and 0.0279, respectively). Our findings suggested that variations in DAB1 involved in the Reelin signaling pathway might contribute to genetic susceptibility to autism with Chinese Han decent, supporting the defect in the Reelin signaling pathway as a predisposition factor for autism. Copyright © 2013 Elsevier Inc. All rights reserved.

  9. Knockout of the iha gene in uropathogenic Escherichia coli and its influence on biofilm formation%尿路致病性大肠杆菌iha基因敲除及其对细菌生物膜形成的影响

    Institute of Scientific and Technical Information of China (English)

    张晓雷; 毛立群; 葛新; 董小青

    2013-01-01

    Objective To construct the adhesin gene iha mutant of uropathogenic Escherichia coli (UPEC) strain W140,and analyze the effects of iha deletion on UPEC biofilm formation.Methods Knockout of the iha gene was done with plasmid pKD46,pKD3,and pCP20 of Red recombinant system.pKD46 was transformed into W140 strain to express the three recombination proteins of λ phage.The chloramphenicol resistance gene flanked by flipase recognition target (FRT) of pKD3 was amplified by PCR and transformed into W140 strain to replace the iha gene.Finally pCP20 was transformed into W140 strain and expressed flipase recombinase,which deleted the chloramphenicol resistance gene between FRT sites.The differences of biofilm formation ability between the wild strain and the mutant were measured by crystal violet staining.Results PCR verification and DNA sequencing indicated that the iha gene was successfully knocked out and UPEC W140Δiha was constructed.The biofilm growth level of the mutant was significantly lower than that of wild strain (P <0.01).Conclusion The iha gene and its encoding product are involved in the process of UPEC biofilm formation.Suppressing iha gene may provide a new target for controlling urinary tract infection.%目的 构建尿路致病性大肠杆菌(UPEC) W140菌株的黏附素基因iha缺陷株,分析iha基因缺失对UPEC生物膜形成的影响.方法 采用Red重组系统的3种质粒(pKD46、pKD3、pCP20)敲除W140菌株的iha基因.pKD46表达λ噬菌体的3个重组蛋白,转入W140菌株使其具有同源重组能力.以pKD3携带的两侧带有翻转酶结合位点(FRT)的氯霉素抗性基因替换目的基因iha,再利用表达翻转酶重组酶的质粒pCP20将FRT之间的氯霉素抗性基因删除,从而获得iha基因敲除菌株.采用结晶紫染色法比较野生菌株与基因敲除菌株的细菌生物膜形成差异.结果 PCR验证和DNA测序表明,UPEC W140菌株染色体上的iha基因被成功敲除,得到iha基因缺陷株UPEC W140

  10. Effect of gamma-glutamyl kinase gene knock-out on metabolism in L-arginine-producing strain Corynebacterium crenatum 8-193%γ-谷氨酰激酶基因敲除对产L-精氨酸钝齿棒杆菌8-193生理代谢的影响

    Institute of Scientific and Technical Information of China (English)

    李小曼; 赵智; 张英姿; 王宇; 丁久元

    2011-01-01

    [目的]为了阻断L-精氨酸合成的前体物L-谷氨酸的分支代谢途径,增加L-精氨酸合成的代谢流,构建钝齿棒杆菌8-193(Corynebacterium crenatum 8-193)γ-谷氨酰激酶(EC:2.7.2.11,γ-glutamyl kinase)基因proB敲除的菌株,并研究proB基因敲除对菌株生理特性的影响.[方法]运用PCR技术分别扩增proB基因的上游和下游序列,构建带有内部缺失的proB基因的敲除载体.经过两次同源重组,敲除C.crenatum 8-193的proB基因,构建菌株8-193-ΔproB,并用带有proB基因的表达载体对8-193-ΔproB进行互补验证.通过摇瓶发酵研究8-193-ΔproB的生理特性.[结果]PCR验证、γ-谷氨酰激酶酶活测定和营养缺陷型鉴定表明,获得了proB基因缺陷的菌株.摇瓶发酵结果表明,与出发菌株相比,8-193-ΔproB生物量降低9.6%,L-精氨酸产量提高13.6%.副产物中谷氨酸族和天冬氨酸族氨基酸含量升高;α-酮戊二酸、磷酸烯醇式丙酮酸和琥珀酸含量降低.proB基因敲除后,菌株的磷酸烯醇式丙酮酸羧化酶和丙酮酸羧化酶活性提高.[结论]对谷氨酸分支代谢途径的阻断可以改善8-193菌株的葡萄糖利用和精氨酸合成能力.%[Objective] In order to optimize precursor supply for L-arginine biosynthesis, we constructed a Corynebacterium crenatum 8-193 mutant with gamma-glutamyl kinase gene (proB) in-frame deletion. The effects of proB knock-out on physiological characteristics of the mutant were investigated. [ Methods ] The upstream and downstream fragments of proB were cloned from C. Crenatum 8-193 chromosome and ligated to integration vector. The mutant C. Crenatum 8-193-△proB was obtained by homologous recombination. The mutant phenotype can be reversed by complementation with proB gene from the expression vector. The physiological characteristics of the mutant were investigated by measurement of the activities of phosphoenolpyruvate carboxylase ( PEPCx) and pyruvate carboxylase (PYC). [Results

  11. Analysis of knockout mice suggests a role for VGF in the control of fat storage and energy expenditure

    Directory of Open Access Journals (Sweden)

    Chakraborty Tandra

    2009-10-01

    Full Text Available Abstract Background Previous studies of mixed background mice have demonstrated that targeted deletion of Vgf produces a lean, hypermetabolic mouse that is resistant to diet-, lesion-, and genetically-induced obesity. To investigate potential mechanism(s and site(s of action of VGF, a neuronal and endocrine secreted protein and neuropeptide precursor, we further analyzed the metabolic phenotypes of two independent VGF knockout lines on C57Bl6 backgrounds. Results Unlike hyperactive VGF knockout mice on a mixed C57Bl6-129/SvJ background, homozygous mutant mice on a C57Bl6 background were hypermetabolic with similar locomotor activity levels to Vgf+/Vgf+ mice, during day and night cycles, indicating that mechanism(s other than hyperactivity were responsible for their increased energy expenditure. In Vgf-/Vgf- knockout mice, morphological analysis of brown and white adipose tissues (BAT and WAT indicated decreased fat storage in both tissues, and decreased adipocyte perimeter and area in WAT. Changes in gene expression measured by real-time RT-PCR were consistent with increased fatty acid oxidation and uptake in BAT, and increased lipolysis, decreased lipogenesis, and brown adipocyte differentiation in WAT, suggesting that increased sympathetic nervous system activity in Vgf-/Vgf- mice may be associated with or responsible for alterations in energy expenditure and fat storage. In addition, uncoupling protein 1 (UCP1 and UCP2 protein levels, mitochondrial number, and mitochondrial cristae density were upregulated in Vgf-/Vgf- BAT. Using immunohistochemical and histochemical techniques, we detected VGF in nerve fibers innervating BAT and Vgf promoter-driven reporter expression in cervical and thoracic spinal ganglia that project to and innervate the chest wall and tissues including BAT. Moreover, VGF peptide levels were quantified by radioimmunoassay in BAT, and were found to be down-regulated by a high fat diet. Lastly, despite being hypermetabolic

  12. Reference genes for gene expression studies in wheat flag leaves grown under different farming conditions

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    Cordeiro Raposo Fernando

    2011-09-01

    Full Text Available Abstract Background Internal control genes with highly uniform expression throughout the experimental conditions are required for accurate gene expression analysis as no universal reference genes exists. In this study, the expression stability of 24 candidate genes from Triticum aestivum cv. Cubus flag leaves grown under organic and conventional farming systems was evaluated in two locations in order to select suitable genes that can be used for normalization of real-time quantitative reverse-transcription PCR (RT-qPCR reactions. The genes were selected among the most common used reference genes as well as genes encoding proteins involved in several metabolic pathways. Findings Individual genes displayed different expression rates across all samples assayed. Applying geNorm, a set of three potential reference genes were suitable for normalization of RT-qPCR reactions in winter wheat flag leaves cv. Cubus: TaFNRII (ferredoxin-NADP(H oxidoreductase; AJ457980.1, ACT2 (actin 2; TC234027, and rrn26 (a putative homologue to RNA 26S gene; AL827977.1. In addition of these three genes that were also top-ranked by NormFinder, two extra genes: CYP18-2 (Cyclophilin A, AY456122.1 and TaWIN1 (14-3-3 like protein, AB042193 were most consistently stably expressed. Furthermore, we showed that TaFNRII, ACT2, and CYP18-2 are suitable for gene expression normalization in other two winter wheat varieties (Tommi and Centenaire grown under three treatments (organic, conventional and no nitrogen and a different environment than the one tested with cv. Cubus. Conclusions This study provides a new set of reference genes which should improve the accuracy of gene expression analyses when using wheat flag leaves as those related to the improvement of nitrogen use efficiency for cereal production.

  13. Development of genetic diagnosing method for diabetes and cholecystitis based on gene analysis of CCK-A receptor

    Energy Technology Data Exchange (ETDEWEB)

    Kono, Akira [National Kyushu Cancer Center, Fukuoka (Japan)

    2000-02-01

    Based on the gene analysis of cholecystokinin type A receptor (CCKAR) from normal mouse and its sequence analysis in the previous year, CCKAR knock-out gene which allows mRNA expression of {beta}-galactosidase gene in stead of CCKAR gene was constructed. Since some abnormality in CCKAR gene is thought to be a causal factor of diabetes and cholecystitis, a knock-out mouse that expressed LacZ but not CCKAR was constructed to investigate the correlation between the clinical features of diabetes and cholecystitis, and CCKAR gene abnormalities. F2 mice that had mutations in CCKAR gene were born according to the Mendel's low. The expression of CCKAR gene was investigated in detail based on the expression of LacZ gene in various tissues of homo (-/-) and hetero (-/+) knockout mice. Comparative study on blood sugar level, blood insulin level, the formation of biliary calculus, etc. is underway with the wild mouse, hetero and homo knockout mouse. (M.N.)

  14. Selection of reliable reference genes for gene expression studies in peach using real-time PCR

    Directory of Open Access Journals (Sweden)

    Zhou Jun

    2009-07-01

    Full Text Available Abstract Background RT-qPCR is a preferred method for rapid and reliable quantification of gene expression studies. Appropriate application of RT-qPCR in such studies requires the use of reference gene(s as an internal control to normalize mRNA levels between different samples for an exact comparison of gene expression level. However, recent studies have shown that no single reference gene is universal for all experiments. Thus, the identification of high quality reference gene(s is of paramount importance for the interpretation of data generated by RT-qPCR. Only a few studies on reference genes have been done in plants and none in peach (Prunus persica L. Batsch. Therefore, the present study was conducted to identify suitable reference gene(s for normalization of gene expression in peach. Results In this work, eleven reference genes were investigated in different peach samples using RT-qPCR with SYBR green. These genes are: actin 2/7 (ACT, cyclophilin (CYP2, RNA polymerase II (RP II, phospholipase A2 (PLA2, ribosomal protein L13 (RPL13, glyceraldehyde-3-phosphate dehydrogenase (GAPDH, 18S ribosomal RNA (18S rRNA, tubblin beta (TUB, tubblin alpha (TUA, translation elongation factor 2 (TEF2 and ubiquitin 10 (UBQ10. All eleven reference genes displayed a wide range of Cq values in all samples, indicating that they expressed variably. The stability of these genes except for RPL13 was determined by three different descriptive statistics, geNorm, NormFinder and BestKeeper, which produced highly comparable results. Conclusion Our study demonstrates that expression stability varied greatly between genes studied in peach. Based on the results from geNorm, NormFinder and BestKeeper analyses, for all the sample pools analyzed, TEF2, UBQ10 and RP II were found to be the most suitable reference genes with a very high statistical reliability, and TEF2 and RP II for the other sample series, while 18S rRNA, RPL13 and PLA2 were unsuitable as internal controls

  15. Expression of calcium/calAulin kinaseⅡα in fragile X mental retardation 1 gene knockout brain tissues in mice%CaMKⅡα在FMR1基因敲除小鼠脑组织中的表达

    Institute of Scientific and Technical Information of China (English)

    韦朝霞; 陈盛强; 陈希; 戴丽军

    2013-01-01

    目的 观察FMRI基因敲除型(KO)小鼠脑组织中钙/钙调素依赖蛋白激酶Ⅱα(CaMKⅡα)表达的改变,探讨CaMKⅡα是否为脆性X综合征相关蛋白(FMRP)的下调蛋白. 方法 PCR鉴定FVB近交系小鼠的基因型,按基因型的不同分为KO组和野生型(WT)组,每组10只.免疫组化染色检测KO及WT小鼠脑组织CaMKⅡα的表达与分布,用图像分析仪分别采集不同脑区免疫信号的吸光度(A)值进行比较. 结果 免疫组化染色检测显示KO与WT小鼠各个脑区普遍存在阳性信号;神经元胞浆尤其是靠近胞体的近端突起上信号呈强阳性,树突中亦有阳性信号,轴突上信号较弱;KO小鼠各脑区CaMKⅡα阳性信号的A值均较WT小鼠显著增高,差异有统计学意义(P<0.05). 结论 CaMKⅡα在成年KO小鼠各脑区的表达均显著增多,提示FMRP负性调节CaMKⅡα的表达.%Objective To observe the expression of calcium/calAulin kinaseⅡα (CaMKⅡα) in the brain tissues of fragile X mental retardation 1 (FMR1) gene knockout (KO) mice to investigate whether CaMKⅡα is regulated by fragile X mental retardation protein (FMRP).Methods According to the gene types of the FVB inbred mice identified by PCR,20 mice were divided into KO group and WT (wide type) group (n=10).The subcellular distribution and expression of CaMKⅡα were observed by immunohistochemical staining; the mean optical density (A) values of immunostaining signal of CaMKⅡα in various brain regions,including the motor cortex,temporal cortex,amygdala,hypothalamus and hippocampus,were determined by IBAS 2.0 image-analyzed system.Results CaMKⅡα immunoreactive cells were abundantly found in all brain subregions of KO and WT mice; especial positive signal was noted in the proximal processes of neurons,so as to those in the dendrite; week signcal was observed in the axon.No distributional difference was found between KO and WT mice.As compared with those in the WT mice,the A values were

  16. MicroRNA-134在FMR1基因敲除鼠脑组织中的表达及意义%Expression and significance of microRNA-134 in mouse brain tissue with FMR1 gene knockout

    Institute of Scientific and Technical Information of China (English)

    曾志涌; 邸伟; 肖都; 孙逊沙; 王玉良; 欧阳梅; 易咏红

    2010-01-01

    Objective To observe the expression ofmicroRNA-134 (miR-134) in the mouse brain tissue with FMR1 gene knockout during the different development periods and its expression characteristic, and explore whether the deficiency of fragile X mental retardation protein (FMRP) can induce the changes of miR-134 transcription. Methods FVB strain male mice, including FMR1 gene knockout (KO, n=15) and their wild type (WT, n=15) counterparts were chosen in the experiment. The expressions of miR-134 in the brain tissues of these KO mice that were 0 d, 4 and 6 w old and the age-matched WT mice were detected by qRT-PCR. Results The transcriptional level of miR-134 in the brain tissue of KO mice had no significant difference as compared with that of age-matched WT mice (P>0.05). The transcriptional levels of miR-134 in 6-w-old KO and WT mice were significantly decreased as compared with the newbom and 4-w-old same genotype mice (P<0.05). Conclusion The absence of FMRP does not influence the transcription of miR-134 and the transcriptional level of miR-134 in the brain tissues maintains a high level during the developmental stage of the nervous system and gradually decreases to a low level after grow-up, demonstrating its important role in regulating the development of nervous system.%目的 观察脆性X综合征(FXS)模型小鼠不同发育时期脑组织中microRNA-134(miR-134)的表达,明确miR-134的表达特点及脆性X智力低下蛋白(FMRP)缺失是否导致miR-134转录的改变. 方法 应用荧光实时定量PCR检测FVB近交系雄性0 d、4、6周(W)龄FMR1基因敲除型(KO)(KO0d、KO4w、KO6w)和同龄野生型(WT)(WT0d、WT4w、WT6w)小鼠脑组织中miR-134的表达(n=5). 结果同龄KO与WT小鼠miR-134的转录表达量差异无统计学意义(P>0.05);KO6w小鼠脑组织miR-134的转录表达量低于KO0d和KO2w小鼠,WT6w小鼠脑组织miR-134的转录表达量也低于WT0d和WT2w小鼠,差异均有统计学意义(P<0.05). 结论 FMRp

  17. Expressions of Drebrins and lcam-5 in mouse cerebral cortex with Fmr-1 gene knockout and their significance in fragile X syndrome%Drebrins和Icam-5在Fmr-1基因敲除鼠大脑皮层的表达和意义

    Institute of Scientific and Technical Information of China (English)

    徐琴; 竺智伟; 赵正言

    2012-01-01

    [Objective]To investigate and compare the changes of Drebrin A,Drebrin E and lcam-5 mRNA levels in the cerebral cortex of Frr-1 gene knockout mouse during brain development periods.[Methods]Fmr-1 gene knockout (KO) male mice and their wild type (WT) counterparts were chosen in our experiment (4≤n≤ 10);the levels of target mRNAs were detected by real time quantitative PCR;check points were set on the 7th,14th,21th and 28rh postnatal d.[Results] The mRNA level of Drebrin A in the KO group was significantly lower than that in the WT group on the 14th postnatal d,while that of Drebrin E was significantly higher than that in the WT group (P<0.05).The mRNA level of lcam-5 in the KO group was significantly higher than that in the WT group on the 14th and 21th postnatal d (P<0.05).[Conclusion] The delayed shift of Drebrin A to Drebrin E and transitional over-expression of lcam-5 in developmental cerebral cortex are the reasons for mental retardation in Fragile X Syndrome.%目的 观察脆性X综合征(FXS)模型小鼠不同发育时期大脑皮层中Drebrin A、Drebrin E及Icam-5 mRNA水平变化情况及意义.方法 应用荧光实时定量PCR(RT-PCR)法检测FmrJ基因敲除KO小鼠及野生健康对照小鼠H出生后第7天、第14天、第21天和第28天大脑皮层Drebrin A、Drebrin E及Icam-5 mRNA的表达(4≤n≤10).结果 KO组小鼠出生后第14天Drebrin A mRNA水平较健康对照组小鼠明显降低,而同时间Drebrin E mRNA水平较健康对照组小鼠明显增高,差异均有统计学意义(P<0.05);KO组小鼠Icam-5 mRNA水平在出生后第14和21天均明显高于健康对照组,差异均有统计学意义(P<0.05).结论 Drebrin A和Drebrin E在大脑皮层发育期的表达交替延迟及Icam-5的一过性过度表达是FXS智力低下的原因之一.

  18. Knockout of the vascular endothelial glucocorticoid receptor abrogates dexamethasone-induced hypertension

    Science.gov (United States)

    GOODWIN, Julie E.; ZHANG, Junhui; GONZALEZ, David; ALBINSSON, Sebastian; GELLER, David S.

    2012-01-01

    Glucocorticoid-mediated hypertension is incompletely understood. Recent studies have suggested the primary mechanism of this form of hypertension may be through the effects of glucocorticoids on vascular tissues and not to excess sodium and water reabsorption as traditionally believed. Objective The goal of this study was to better understand the role of the vasculature in the generation and maintenance of glucocorticoid-mediated hypertension. Methods We created a mouse model with a tissue-specific knockout of the glucocorticoid receptor in the vascular endothelium. Results We show that these mice are relatively resistant to dexamethasone-induced hypertension. After one week of dexamethasone treatment, control animals have a mean blood pressure increase of 13.1 mm Hg while knockout animals have only a 2.7 mm Hg increase (p<0.001). Interestingly, the knockout mice have slightly elevated baseline BP compared to the controls (112.2 ± 2.5 mm Hg vs. 104.6 ± 1.2 mm Hg, p = 0.04), a finding which is not entirely explained by our data. Furthermore, we demonstrate that the knockout resistance arterioles have a decreased contractile response to dexamethasone with only 6.6% contraction in knockout vessels compared to 13.4% contraction in control vessels (p=0.034). Finally, we show that in contrast to control animals, the knockout animals are able to recover a significant portion of their normal circadian blood pressure rhythm suggesting that the vascular endothelial glucocorticoid receptor may function as a peripheral circadian clock. Conclusions Our study highlights the importance of the vascular endothelial GR in several fundamental physiologic processes, namely blood pressure homeostasis and circadian rhythm. PMID:21659825

  19. MR histology of advanced atherosclerotic lesions of ApoE- knockout mice

    Science.gov (United States)

    Naumova, A.; Yarnykh, V.; Ferguson, M.; Rosenfeld, M.; Yuan, C.

    2016-02-01

    The purposes of this study were to examine the feasibility of determining the composition of advanced atherosclerotic plaques in fixed ApoE-knockout mice and to develop a time-efficient microimaging protocol for MR histological imaging on mice. Five formalin-fixed transgenic ApoE-knockout mice were imaged at the 9.4T Bruker BioSpec MR scanner using 3D spoiled gradient-echo sequence with an isotropic field of view of 24 mm3; TR 20.8 ms; TE 2.6 ms; flip angle 20°, resulted voxel size 47 × 63 × 94 pm3. MRI examination has shown that advanced atherosclerotic lesions of aorta, innominate and carotid arteries in ApoE-knockout mice are characterized by high calcification and presence of the large fibrofatty nodules. MRI quantification of atherosclerotic lesion components corresponded to histological assessment of plaque composition with a correlation coefficient of 0.98.

  20. One-neutron knockout from {sup 24-28}Ne isotopes

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez-Tajes, C., E-mail: carme.rodriguez@usc.e [Departamento de Fisica de Particulas, Universidade de Santiago de Compostela, 15782 Santiago de Compostela (Spain); Cortina-Gil, D.; Alvarez-Pol, H. [Departamento de Fisica de Particulas, Universidade de Santiago de Compostela, 15782 Santiago de Compostela (Spain); Aumann, T. [GSI Helmholtzzentrum fuer Schwerionenforschung, 64291 Darmstadt (Germany); Benjamim, E.; Benlliure, J. [Departamento de Fisica de Particulas, Universidade de Santiago de Compostela, 15782 Santiago de Compostela (Spain); Borge, M.J.G. [Instituto de Estructura de la Materia, CSIC, 28006 Madrid (Spain); Caamano, M.; Casarejos, E. [Departamento de Fisica de Particulas, Universidade de Santiago de Compostela, 15782 Santiago de Compostela (Spain); Chatillon, A. [GSI Helmholtzzentrum fuer Schwerionenforschung, 64291 Darmstadt (Germany); Eppinger, K.; Faestermann, T. [Physik Department E12, Technische Universitaet Muenchen, 85748 Garching (Germany); Gascon, M. [Departamento de Fisica de Particulas, Universidade de Santiago de Compostela, 15782 Santiago de Compostela (Spain); Geissel, H. [GSI Helmholtzzentrum fuer Schwerionenforschung, 64291 Darmstadt (Germany); Gernhaeuser, R. [Physik Department E12, Technische Universitaet Muenchen, 85748 Garching (Germany); Jonson, B. [Fundamental Fysik, Chalmers Tekniska Hoegskola, 412 96 Goeteborg (Sweden); PH Department, CERN, 1211 Geneve 23 (Switzerland); Kanungo, R. [Astronomy and Physics Department, Saint Mary' s University, Halifax, NS B3H 3C3 (Canada); Kruecken, R. [Physik Department E12, Technische Universitaet Muenchen, 85748 Garching (Germany); Kurtukian, T. [Departamento de Fisica de Particulas, Universidade de Santiago de Compostela, 15782 Santiago de Compostela (Spain); Larsson, K. [Fundamental Fysik, Chalmers Tekniska Hoegskola, 412 96 Goeteborg (Sweden)

    2010-04-05

    One-neutron knockout reactions of {sup 24-28}Ne in a beryllium target have been studied in the Fragment Separator (FRS), at GSI. The results include inclusive one-neutron knockout cross-sections as well as longitudinal-momentum distributions of the knockout fragments. The ground-state structure of the neutron-rich neon isotopes was obtained from an analysis of the measured momentum distributions. The results indicate that the two heaviest isotopes, {sup 27}Ne and {sup 28}Ne, are dominated by a configuration in which a s{sub 1/2} neutron is coupled to an excited state of the {sup 26}Ne and {sup 27}Ne core, respectively.

  1. Two-neutron knockout from neutron-deficient $^{34}$Ar, $^{30}$S, and $^{26}$Si

    CERN Document Server

    Yoneda, K; Brown, B A; Campbell, C M; Cook, J M; Cottle, P D; Davies, A D; Dinca, D C; Gade, A; Glasmacher, T; Hansen, P G; Hoagland, T; Kemper, K W; Lecouey, J L; Müller, W F; Obertelli, A; Reynolds, R R; Terry, J R; Tostevin, J A; Zwahlen, H

    2006-01-01

    Two-neutron knockout reactions from nuclei in the proximity of the proton dripline have been studied using intermediate-energy beams of neutron-deficient $^{34}$Ar, $^{30}$S, and $^{26}$Si. The inclusive cross sections, and also the partial cross sections for the population of individual bound final states of the $^{32}$Ar, $^{28}$S and $^{24}$Si knockout residues, have been determined using the combination of particle and $\\gamma$-ray spectroscopy. Similar to the two-proton knockout mechanism on the neutron-rich side of the nuclear chart, these two-neutron removal reactions from already neutron-deficient nuclei are also shown to be consistent with a direct reaction mechanism.

  2. Assessment of Suitable Reference Genes for Quantitative Gene Expression Studies in Melon Fruits.

    Science.gov (United States)

    Kong, Qiusheng; Gao, Lingyun; Cao, Lei; Liu, Yue; Saba, Hameed; Huang, Yuan; Bie, Zhilong

    2016-01-01

    Melon (Cucumis melo L.) is an attractive model plant for investigating fruit development because of its morphological, physiological, and biochemical diversity. Quantification of gene expression by quantitative reverse transcription polymerase chain reaction (qRT-PCR) with stably expressed reference genes for normalization can effectively elucidate the biological functions of genes that regulate fruit development. However, the reference genes for data normalization in melon fruits have not yet been systematically validated. This study aims to assess the suitability of 20 genes for their potential use as reference genes in melon fruits. Expression variations of these genes were measured in 24 samples that represented different developmental stages of fertilized and parthenocarpic melon fruits by qRT-PCR analysis. GeNorm identified ribosomal protein L (CmRPL) and cytosolic ribosomal protein S15 (CmRPS15) as the best pair of reference genes, and as many as five genes including CmRPL, CmRPS15, TIP41-like family protein (CmTIP41), cyclophilin ROC7 (CmCYP7), and ADP ribosylation factor 1 (CmADP) were required for more reliable normalization. NormFinder ranked CmRPS15 as the best single reference gene, and RAN GTPase gene family (CmRAN) and TATA-box binding protein (CmTBP2) as the best combination of reference genes in melon fruits. Their effectiveness was further validated by parallel analyses on the activities of soluble acid invertase and sucrose phosphate synthase, and expression profiles of their respective encoding genes CmAIN2 and CmSPS1, as well as sucrose contents during melon fruit ripening. The validated reference genes will help to improve the accuracy of gene expression studies in melon fruits.

  3. Exploring valid reference genes for gene expression studies in Brachypodium distachyon by real-time PCR

    Directory of Open Access Journals (Sweden)

    Xiang Fengning

    2008-11-01

    Full Text Available Abstract Background The wild grass species Brachypodium distachyon (Brachypodium hereafter is emerging as a new model system for grass crop genomics research and biofuel grass biology. A draft nuclear genome sequence is expected to be publicly available in the near future; an explosion of gene expression studies will undoubtedly follow. Therefore, stable reference genes are necessary to normalize the gene expression data. Results A systematic exploration of suitable reference genes in Brachypodium is presented here. Nine reference gene candidates were chosen, and their gene sequences were obtained from the Brachypodium expressed sequence tag (EST databases. Their expression levels were examined by quantitative real-time PCR (qRT-PCR using 21 different Brachypodium plant samples, including those from different plant tissues and grown under various growth conditions. Effects of plant growth hormones were also visualized in the assays. The expression stability of the candidate genes was evaluated using two analysis software packages, geNorm and NormFinder. In conclusion, the ubiquitin-conjugating enzyme 18 gene (UBC18 was validated as a suitable reference gene across all the plant samples examined. While the expression of the polyubiquitin genes (Ubi4 and Ubi10 was most stable in different plant tissues and growth hormone-treated plant samples, the expression of the S-adenosylmethionine decarboxylase gene (SamDC ranked was most stable in plants grown under various environmental stresses. Conclusion This study identified the reference genes that are most suitable for normalizing the gene expression data in Brachypodium. These reference genes will be particularly useful when stress-responsive genes are analyzed in order to produce transgenic plants that exhibit enhanced stress resistance.

  4. Assessment of Suitable Reference Genes for Quantitative Gene Expression Studies in Melon Fruits

    Science.gov (United States)

    Kong, Qiusheng; Gao, Lingyun; Cao, Lei; Liu, Yue; Saba, Hameed; Huang, Yuan; Bie, Zhilong

    2016-01-01

    Melon (Cucumis melo L.) is an attractive model plant for investigating fruit development because of its morphological, physiological, and biochemical diversity. Quantification of gene expression by quantitative reverse transcription polymerase chain reaction (qRT-PCR) with stably expressed reference genes for normalization can effectively elucidate the biological functions of genes that regulate fruit development. However, the reference genes for data normalization in melon fruits have not yet been systematically validated. This study aims to assess the suitability of 20 genes for their potential use as reference genes in melon fruits. Expression variations of these genes were measured in 24 samples that represented different developmental stages of fertilized and parthenocarpic melon fruits by qRT-PCR analysis. GeNorm identified ribosomal protein L (CmRPL) and cytosolic ribosomal protein S15 (CmRPS15) as the best pair of reference genes, and as many as five genes including CmRPL, CmRPS15, TIP41-like family protein (CmTIP41), cyclophilin ROC7 (CmCYP7), and ADP ribosylation factor 1 (CmADP) were required for more reliable normalization. NormFinder ranked CmRPS15 as the best single reference gene, and RAN GTPase gene family (CmRAN) and TATA-box binding protein (CmTBP2) as the best combination of reference genes in melon fruits. Their effectiveness was further validated by parallel analyses on the activities of soluble acid invertase and sucrose phosphate synthase, and expression profiles of their respective encoding genes CmAIN2 and CmSPS1, as well as sucrose contents during melon fruit ripening. The validated reference genes will help to improve the accuracy of gene expression studies in melon fruits. PMID:27536316

  5. Generation and characterisation of keratin 7 (K7 knockout mice.

    Directory of Open Access Journals (Sweden)

    Aileen Sandilands

    Full Text Available Keratin 7 (K7 is a Type II member of the keratin superfamily and despite its widespread expression in different types of simple and transitional epithelia, its functional role in vivo remains elusive, in part due to the lack of any appropriate mouse models or any human diseases that are associated with KRT7 gene mutations. Using conventional gene targeting in mouse embryonic stem cells, we report here the generation and characterisation of the first K7 knockout mouse. Loss of K7 led to increased proliferation of the bladder urothelium although this was not associated with hyperplasia. K18, a presumptive type I assembly partner for K7, showed reduced expression in the bladder whereas K20, a marker of the terminally differentiated superficial urothelial cells was transcriptionally up-regulated. No other epithelia were seen to be adversely affected by the loss of K7 and western blot and immunofluorescence microscopy analysis revealed that the expression of K8, K18, K19 and K20 were not altered in the absence of K7, with the exception of the kidney where there was reduced K18 expression.

  6. 磷酸烯醇式丙酮酸羧化酶基因的敲除对于谷氨酸棒杆菌V1生理代谢的影响%Effect of phosphoenolpyruvate carboxylase gene knock-out on physiological metabolism in Corynebacterium glutamicum V1

    Institute of Scientific and Technical Information of China (English)

    仇爱梅; 窦文芳; 李会; 许正宏

    2012-01-01

    [Objective] In order to optimize precursor supply for L-valine biosynthesis, a Corynebacterium glutamicum V1 mutant with phosphoenolpyruvate carboxylase gene (pepc) in-frame deletion was constructed through crossover PCR and homologous recombination. The effect of pepc knock-out on physiological characteristics of the mutant was investigated. [Methods] The upstream and downstream fragments of pepc were cloned from C. glutamicum V1 chromosome and ligated to integration vector. The mutant C. glutamicum V1-Δpepc was screened by homologous recombination. The physiological characteristics of the mutant were investigated by fermentation experiments and enzymes activity measurement of pyruvate carboxylase (PC), pyruvate dehydrogenase (PDH) and pyruvate kinase (PK). The mutant with pepc gene in-frame deletion was screened and confirmed by PCR and phosphoenolpyruvate carboxylase activity determination. [Results] The pepc knock-out resulted in L-argine accumulation to 7.48 g/L and no accumulation of L-valine, which accompanied by increase of PDH activity and PC activity in C. glutamicum V1-Δpepc. The knock-out of pepc gene affected the metabolism of the strain to some extent. [Conclusion] Blocking the anaplerotic pathway PEPC participated increased TCA cycle, leading to the increase of L-argine and decrease of amino acids with pyruvic acid as precursor , such as L-valine and alanine.%[目的]L-缬氨酸生物合成的前体物质是丙酮酸.为了增加磷酸烯醇式丙酮酸向丙酮酸的代谢流向,优化L-缬氨酸前体物质的供应,以一株积累L-缬氨酸的谷氨酸棒杆菌V1 (Corynebacterium glutamicum V1)为对象,构建磷酸烯醇式丙酮酸羧化酶(PEPC)基因敲除的重组菌株C.glutamicum V1-△pepc,并研究pepc敲除后菌株生理特性的改变.[方法]运用交叉PCR方法得到pepc基因内部缺失的同源片段△pepc,并构建敲除质粒pK18mobsacB-△pepc.利用同源重组技术获得pepc基因缺陷突变株C.glutamicum V1-△pepc

  7. Validation of housekeeping genes for studying differential gene expression in the bovine myometrium.

    Science.gov (United States)

    Rekawiecki, Robert; Kowalik, Magdalena K; Kotwica, Jan

    2013-12-01

    The aim of this study was to determine the steady-state expression of 13 selected housekeeping genes in the myometrium of cyclic and pregnant cows. Cells taken from bovine myometrium on days 1-5, 6-10, 11-16 and 17-20 of the oestrous cycle and in weeks 3-5, 6-8 and 9-12 of pregnancy were used. Reverse transcribed RNA was amplified in real-time PCR using designed primers. Reaction efficiency was determined with the Linreg programme. The geNorm and NormFinder programmes were used to select the best housekeeping genes. They calculate the expression stability factor for each used housekeeping gene with the smallest value for most stably expressed genes. According to geNorm, the most stable housekeeping genes in the myometrium were C2orf29, TPB and TUBB2B, while the least stably expressed genes were 18S RNA, HPRT1 and GAPDH. NormFinder identified the best genes in the myometrium as C2orf29, MRPL12 and TBP, while the worst genes were 18S RNA, B2M and SF3A1. Differences in stability factors between the two programmes may also indicate that the physiological status of the female, e.g. pregnancy, affects the stability of expression of housekeeping genes. The different expression stability of housekeeping genes did not affect progesterone receptor expression but it could be important if small differences in gene expression were measured between studies.

  8. Identification of reference genes in human myelomonocytic cells for gene expression studies in altered gravity.

    Science.gov (United States)

    Thiel, Cora S; Hauschild, Swantje; Tauber, Svantje; Paulsen, Katrin; Raig, Christiane; Raem, Arnold; Biskup, Josefine; Gutewort, Annett; Hürlimann, Eva; Unverdorben, Felix; Buttron, Isabell; Lauber, Beatrice; Philpot, Claudia; Lier, Hartwin; Engelmann, Frank; Layer, Liliana E; Ullrich, Oliver

    2015-01-01

    Gene expression studies are indispensable for investigation and elucidation of molecular mechanisms. For the process of normalization, reference genes ("housekeeping genes") are essential to verify gene expression analysis. Thus, it is assumed that these reference genes demonstrate similar expression levels over all experimental conditions. However, common recommendations about reference genes were established during 1 g conditions and therefore their applicability in studies with altered gravity has not been demonstrated yet. The microarray technology is frequently used to generate expression profiles under defined conditions and to determine the relative difference in expression levels between two or more different states. In our study, we searched for potential reference genes with stable expression during different gravitational conditions (microgravity, normogravity, and hypergravity) which are additionally not altered in different hardware systems. We were able to identify eight genes (ALB, B4GALT6, GAPDH, HMBS, YWHAZ, ABCA5, ABCA9, and ABCC1) which demonstrated no altered gene expression levels in all tested conditions and therefore represent good candidates for the standardization of gene expression studies in altered gravity.

  9. Effects of adhE Gene Knock-out on Hydrogen Evolution of Klebsiella oxytoca HP1%Klebsiella oxytoca HP1乙醇脱氢酶基因敲除对产氢的影响

    Institute of Scientific and Technical Information of China (English)

    徐方成; 洪华生

    2007-01-01

    Klebsiella oxytoca HP1是从温泉筛选得到的很有潜力的产氢菌株.为了进一步提高产氢能力,应用同源重组技术构建了乙醇途径缺少菌株,并分析和比较了野生菌和工程菌的代谢流量分布.%Klebsiella oxytoca HP1 is a potential H2-producing bacterium we screened from a hot spring. In the present study, metabolic engineering strategy was carried out to construct ethanol pathway mutants by homologous recombination, in order to improve hydrogen production yield. Metabolic fluxes of the wild and the mutants were analysed and compared.

  10. Nitrotyrosinylation, remodeling and endothelial-myocyte uncoupling in iNOS, cystathionine beta synthase (CBS) knockouts and iNOS/CBS double knockout mice.

    Science.gov (United States)

    Kundu, Soumi; Kumar, Munish; Sen, Utpal; Mishra, Paras K; Tyagi, Neetu; Metreveli, Naira; Lominadze, David; Rodriguez, Walter; Tyagi, Suresh C

    2009-01-01

    Increased levels of homocysteine (Hcy), recognized as hyperhomocysteinemia (HHcy), were associated with cardiovascular diseases. There was controversy regarding the detrimental versus cardio protective role of inducible nitric oxide synthase (iNOS) in ischemic heart disease. The aim of this study was to test the hypothesis that the Hcy generated nitrotyrosine by inducing the endothelial nitric oxide synthase, causing endothelial-myocyte (E-M) coupling. To differentiate the role of iNOS versus constitutive nitric oxide synthase (eNOS and nNOS) in Hcy-mediated nitrotyrosine generation and matrix remodeling in cardiac dysfunction, left ventricular (LV) tissue was analyzed from cystathionine beta synthase (CBS) heterozygote knockout, iNOS homozygote knockout, CBS-/+/iNOS-/- double knockout, and wild-type (WT) mice. The levels of nitrotyrosine, MMP-2 and -9 (zymographic analysis), and fibrosis (by trichrome stain) were measured. The endothelial-myocyte function was determined in cardiac rings. In CBS-/+ mice, homocysteine was elevated and in iNOS-/- mice, nitric oxide was significantly reduced. The nitrotyrosine and matrix metalloproteinase-9 (MMP-9) levels were elevated in double knockout and CBS-/+ as compared to WT mice. Although MMP-2 levels were similar in CBS-/+, iNOS-/-, and CBS-/+/iNOS-/-, the levels were three- to fourfold higher than WT. The levels of collagen were similar in CBS-/+ and iNOS-/-, but they were threefold higher than WT. Interesting, the levels of collagen increased sixfold in double knockouts, compared to WT, suggesting synergism between high Hcy and lack of iNOS. Left ventricular hypertrophy was exaggerated in the iNOS-/- and double knockout, and mildly increased in the CBS-/+, compared to WT mice. The endothelial-dependent relaxation was attenuated to the same extent in the CBS-/+ and iNOS-/-, compared to WT, but it was robustly blunted in double knockouts. The results concluded that homocysteine generated nitrotyrosine in the vicinity of

  11. Nitrotyrosinylation, Remodeling and Endothelial-Myocyte Uncoupling in iNOS, Cystathionine Beta Synthase (CBS) Knockouts and iNOS/CBS Double Knockout Mice

    Science.gov (United States)

    Kundu, Soumi; Kumar, Munish; Sen, Utpal; Mishra, Paras K.; Tyagi, Neetu; Metreveli, Naira; Lominadze, David; Rodriguez, Walter; Tyagi, Suresh C.

    2009-01-01

    Increased levels of homocysteine (Hcy), recognized as hyperhomocysteinemia (HHcy), were associated with cardiovascular diseases. There was controversy regarding the detrimental versus cardio protective role of inducible nitric oxide synthase (iNOS) in ischemic heart disease. The aim of this study was to test the hypothesis that the Hcy generated nitrotyrosine by inducing the endothelial nitric oxide synthase, causing endothelial-myocyte (E–M) coupling. To differentiate the role of iNOS versus constitutive nitric oxide synthase (eNOS and nNOS) in Hcy-mediated nitrotyrosine generation and matrix remodeling in cardiac dysfunction, left ventricular (LV) tissue was analyzed from cystathionine beta synthase (CBS) heterozygote knockout, iNOS homozygote knockout, CBS−/+/iNOS−/− double knockout, and wild-type (WT) mice. The levels of nitrotyrosine, MMP-2 and -9 (zymographic analysis), and fibrosis (by trichrome stain) were measured. The endothelial-myocyte function was determined in cardiac rings. In CBS−/+ mice, homocysteine was elevated and in iNOS−/− mice, nitric oxide was significantly reduced. The nitrotyrosine and matrix metalloproteinase-9 (MMP-9) levels were elevated in double knockout and CBS−/+ as compared to WT mice. Although MMP-2 levels were similar in CBS−/+, iNOS−/−, and CBS−/+/iNOS−/−, the levels were three- to fourfold higher than WT. The levels of collagen were similar in CBS−/+ and iNOS−/−, but they were threefold higher than WT. Interesting, the levels of collagen increased sixfold in double knockouts, compared to WT, suggesting synergism between high Hcy and lack of iNOS. Left ventricular hypertrophy was exaggerated in the iNOS−/− and double knockout, and mildly increased in the CBS−/+, compared to WT mice. The endothelial-dependent relaxation was attenuated to the same extent in the CBS−/+ and iNOS−/−, compared to WT, but it was robustly blunted in double knockouts. The results concluded that homocysteine

  12. Generation of germline ablated male pigs by CRISPR/Cas9 editing of the NANOS2 gene.

    Science.gov (United States)

    Park, Ki-Eun; Kaucher, Amy V; Powell, Anne; Waqas, Muhammad Salman; Sandmaier, Shelley E S; Oatley, Melissa J; Park, Chi-Hun; Tibary, Ahmed; Donovan, David M; Blomberg, Le Ann; Lillico, Simon G; Whitelaw, C Bruce A; Mileham, Alan; Telugu, Bhanu P; Oatley, Jon M

    2017-01-10

    Genome editing tools have revolutionized the generation of genetically modified animals including livestock. In particular, the domestic pig is a proven model of human physiology and an agriculturally important species. In this study, we utilized the CRISPR/Cas9 system to edit the NANOS2 gene in pig embryos to generate offspring with mono-allelic and bi-allelic mutations. We found that NANOS2 knockout pigs phenocopy knockout mice with male specific germline ablation but other aspects of testicular development are normal. Moreover, male pigs with one intact NANOS2 allele and female knockout pigs are fertile. From an agriculture perspective, NANOS2 knockout male pigs are expected to serve as an ideal surrogate for transplantation of donor spermatogonial stem cells to expand the availability of gametes from genetically desirable sires.

  13. Generation of germline ablated male pigs by CRISPR/Cas9 editing of the NANOS2 gene

    Science.gov (United States)

    Park, Ki-Eun; Kaucher, Amy V.; Powell, Anne; Waqas, Muhammad Salman; Sandmaier, Shelley E.S.; Oatley, Melissa J.; Park, Chi-Hun; Tibary, Ahmed; Donovan, David M.; Blomberg, Le Ann; Lillico, Simon G.; Whitelaw, C. Bruce A.; Mileham, Alan; Telugu, Bhanu P.; Oatley, Jon M.

    2017-01-01

    Genome editing tools have revolutionized the generation of genetically modified animals including livestock. In particular, the domestic pig is a proven model of human physiology and an agriculturally important species. In this study, we utilized the CRISPR/Cas9 system to edit the NANOS2 gene in pig embryos to generate offspring with mono-allelic and bi-allelic mutations. We found that NANOS2 knockout pigs phenocopy knockout mice with male specific germline ablation but other aspects of testicular development are normal. Moreover, male pigs with one intact NANOS2 allele and female knockout pigs are fertile. From an agriculture perspective, NANOS2 knockout male pigs are expected to serve as an ideal surrogate for transplantation of donor spermatogonial stem cells to expand the availability of gametes from genetically desirable sires. PMID:28071690

  14. Transient in utero knockout (TIUKO of C-MYC affects late lung and intestinal development in the mouse

    Directory of Open Access Journals (Sweden)

    Zhou Pengbo

    2004-04-01

    Full Text Available Abstract Background Developmentally important genes often result in early lethality in knockout animals. Thus, the direct role of genes in late gestation organogenesis cannot be assessed directly. In utero delivery of transgenes was shown previously to result in high efficiency transfer to pulmonary and intestinal epithelial stem cells. Thus, this technology can be used to evaluate late gestation development. Results In utero gene transfer was used to transfer adenovirus with either an antisense c-myc or a C-MYC ubiquitin targeting protein to knockout out c-myc expression in late gestation lung and intestines. Using either antisense or ubiquitin mediated knockout of C-MYC levels in late gestation resulted in similar effects. Decreased complexity was observed in both intestines and lungs. Stunted growth of villi was evident in the intestines. In the lung, hypoplastic lungs with disrupted aveolarization were observed. Conclusions These data demonstrated that C-MYC was required for cell expansion and complexity in late gestation lung and intestinal development. In addition they demonstrate that transient in utero knockout of proteins may be used to determine the role of developmentally important genes in the lungs and intestines.

  15. Sympathetic hyperinnervation of the uterus in the estrogen receptor alpha knock-out mouse.

    Science.gov (United States)

    Zoubina, E V; Smith, P G

    2001-01-01

    Uterine innervation undergoes cyclical remodeling in the adult virgin rat. Previous studies showed that ovariectomy leads to increased uterine sympathetic nerve density, and this can be reduced by estrogen administration. However, the receptor mechanism by which estrogen modulates sympathetic innervation is unknown. The present study assessed the role of the estrogen receptor alpha in establishing levels of uterine innervation by comparing the nerve abundance in mice with a null mutation of the estrogen receptor alpha with those of the wild-type cycling mouse. Immunostaining for total uterine innervation using antibodies against the pan-neuronal marker protein gene product 9.5 showed that nerve numbers in normally cycling wild-type mice were high in diestrus when circulating estrogen is at its nadir, and low at estrus, coincident with high plasma estrogen. Uteri of the estrogen receptor alpha knock-out mice were smaller than those of wild-type mice, but even when corrected for differences in size, total innervation was 188% and 355% greater than that of wild-type mice at diestrus and estrus, respectively. This hyperinnervation is associated with increased numbers of nerves immunoreactive for the noradrenergic enzyme dopamine beta-hydroxylase, without obvious differences in those containing calcitonin gene-related peptide or the vesicular acetylcholine transporter. While estrogen supplementation of the ovariectomized wild-type mice significantly reduced total uterine innervation, neither ovariectomy nor estrogen supplementation affected uterine nerve density in estrogen receptor alpha knock-out mice.We conclude that estrogen acting through the estrogen receptor alpha determines the number of sympathetic nerve terminal branches within uterine smooth muscle target. In mice with low circulating estrogen, or high estrogen but lacking the functional estrogen receptor alpha, the uterus contains abundant sympathetic nerves, whereas estrogen acts via the estrogen receptor

  16. Brain response to traumatic brain injury in wild-type and interleukin-6 knockout mice: a microarray analysis

    DEFF Research Database (Denmark)

    Poulsen, Christian Bjørn; Penkowa, Milena; Borup, Rehannah

    2005-01-01

    Traumatic injury to the brain is one of the leading causes of injury-related death or disability. Brain response to injury is orchestrated by cytokines, such as interleukin (IL)-6, but the full repertoire of responses involved is not well known. We here report the results obtained with microarrays...... in the initial tissue injury and later regeneration of the parenchyma. IL-6 deficiency showed a dramatic effect in the expression of many genes, especially in the 1 day post-lesion timing, which presumably underlies the poor capacity of IL-6 knockout mice to cope with brain damage. The results highlight...... the importance of IL-6 controlling the response of the brain to injury as well as the suitability of microarrays for identifying specific targets worthy of further study....

  17. A viable model for the study of GABAergic neurons in fmr1 knockout mice%fmr1基因敲除小鼠中间神经元发育研究的新方法

    Institute of Scientific and Technical Information of China (English)

    欧阳梅; 徐明明; 卢韬; 黄越玲; 易咏红

    2011-01-01

    目的:通过杂交技术获得能表达GAD67 -GFP的fmr1基因敲除小鼠模型.方法:fmr1基因敲除(fmr1-ko)雌性小鼠(X-X-)和GAD67-GFP敲入基因杂合雄性小鼠(2+2-)杂交.鼠尾巴提取基因组DNA,用PCR方法鉴定所有子代基因型.对杂交后代小鼠进行行为学观察,并行脑组织切片观察绿色荧光蛋白在γ-氨基丁酸能神经元的表达.结果:PCR方法证实通过杂交繁殖出四种基因型小鼠:同时带有杂合fmr1 ko及GAD67-GFP位点的雌性小鼠(X+ X-/2 +2-)、带有纯合fmr1-ko及GAD67-GFP位点的雄性小鼠(X-Y/2 +2-)、不带有GAD67-GFP的雌性和雄性小鼠(X+X-/2-2-,X-Y/2-2-).观察发现X-Y/2+2-小鼠具有fmr1 -ko小鼠类似的行为学表现,同时在显微镜下观察到X-Y/2+2-小鼠脑组织切片有发绿色荧光的GABA神经元.结论:该杂交小鼠成功表达了GAD67-GFP,为研究γ-氨基丁酸能神经元在脆性X综合征发病机制中的作用提供一种可靠的模型.%Objective: To obtain Fragile X syndrome rat models with GAD67-GFP expression by hybridization technique. Methods; One fmrl-knockout female (X~X~) rat was mated with GAD67-CFP heterozygous male (2 + 2-). All hybrid offspring were genotyped by polymerase chain reaction ( PCR) according to genomic DNA extracted from the tail. The behaviors and the expression of GFP on GABAergic neurons of brain slice were also observed. Results: Four genotypes of mice have been generated: the heterozygous female mice with both the fmrl-gfp-ko and GAD67-GFP locus (X+XV2-2-) , fmrl-ko male mice heterozygous with GAD67-GFP locus (X-Y/2+2-) .female and male mice without GAD67-GFP locus(X+ X/-2-2-,X-Y/2-2-). Mice X-Y2+2-were noted to have similar behaviors with fmrl ko mice. Morphological observation of GABAergic neuron had a good match between the mice X-Y/2+2~and fmrl ko mice. Conclusions:The hybrid mice X-Y/2-2- successfully expressed the GAD67-GFP protein, which provides a viable model for the study on the pathogenetic effect of

  18. 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

  19. Supernova: A Versatile Vector System for Single-Cell Labeling and Gene Function Studies in vivo.

    Science.gov (United States)

    Luo, Wenshu; Mizuno, Hidenobu; Iwata, Ryohei; Nakazawa, Shingo; Yasuda, Kosuke; Itohara, Shigeyoshi; Iwasato, Takuji

    2016-10-24

    Here we describe "Supernova" series of vector systems that enable single-cell labeling and labeled cell-specific gene manipulation, when introduced by in utero electroporation (IUE) or adeno-associated virus (AAV)-mediated gene delivery. In Supernova, sparse labeling relies on low TRE leakage. In a small population of cells with over-threshold leakage, initial tTA-independent weak expression is enhanced by tTA/TRE-positive feedback along with a site-specific recombination system (e.g., Cre/loxP, Flpe/FRT). Sparse and bright labeling by Supernova with little background enables the visualization of the morphological details of individual neurons in densely packed brain areas such as the cortex and hippocampus, both during development and in adulthood. Sparseness levels are adjustable. Labeled cell-specific gene knockout was accomplished by introducing Cre/loxP-based Supernova vectors into floxed mice. Furthermore, by combining with RNAi, TALEN, and CRISPR/Cas9 technologies, IUE-based Supernova achieved labeled cell-specific gene knockdown and editing/knockout without requiring genetically altered mice. Thus, Supernova system is highly extensible and widely applicable for single-cell analyses in complex organs, such as the mammalian brain.

  20. Supernova: A Versatile Vector System for Single-Cell Labeling and Gene Function Studies in vivo

    Science.gov (United States)

    Luo, Wenshu; Mizuno, Hidenobu; Iwata, Ryohei; Nakazawa, Shingo; Yasuda, Kosuke; Itohara, Shigeyoshi; Iwasato, Takuji

    2016-01-01

    Here we describe “Supernova” series of vector systems that enable single-cell labeling and labeled cell-specific gene manipulation, when introduced by in utero electroporation (IUE) or adeno-associated virus (AAV)-mediated gene delivery. In Supernova, sparse labeling relies on low TRE leakage. In a small population of cells with over-threshold leakage, initial tTA-independent weak expression is enhanced by tTA/TRE-positive feedback along with a site-specific recombination system (e.g., Cre/loxP, Flpe/FRT). Sparse and bright labeling by Supernova with little background enables the visualization of the morphological details of individual neurons in densely packed brain areas such as the cortex and hippocampus, both during development and in adulthood. Sparseness levels are adjustable. Labeled cell-specific gene knockout was accomplished by introducing Cre/loxP-based Supernova vectors into floxed mice. Furthermore, by combining with RNAi, TALEN, and CRISPR/Cas9 technologies, IUE-based Supernova achieved labeled cell-specific gene knockdown and editing/knockout without requiring genetically altered mice. Thus, Supernova system is highly extensible and widely applicable for single-cell analyses in complex organs, such as the mammalian brain. PMID:27775045