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Sample records for satbamv rna vectors

  1. Construction of shRNA lentiviral vector

    Directory of Open Access Journals (Sweden)

    Hong Song

    2010-12-01

    Full Text Available Lentiviruses have been adapted as gene delivery vehicles. This article summarized shRNA lentiviral vector methods generally used in research laboratories. The main procedures of shRNA lentiviral vector include that (1 Target sequences screening and shRNA oligonucleotides designing, (2 insert designed oligonucleotides into lentiviral vectors, (3 using packaging cells to produce shRNA lentivirus, and (4 transducing target cells with shRNA lentivirus.

  2. Replicon RNA Viral Vectors as Vaccines

    Science.gov (United States)

    Lundstrom, Kenneth

    2016-01-01

    Single-stranded RNA viruses of both positive and negative polarity have been used as vectors for vaccine development. In this context, alphaviruses, flaviviruses, measles virus and rhabdoviruses have been engineered for expression of surface protein genes and antigens. Administration of replicon RNA vectors has resulted in strong immune responses and generation of neutralizing antibodies in various animal models. Immunization of mice, chicken, pigs and primates with virus-like particles, naked RNA or layered DNA/RNA plasmids has provided protection against challenges with lethal doses of infectious agents and administered tumor cells. Both prophylactic and therapeutic efficacy has been achieved in cancer immunotherapy. Moreover, recombinant particles and replicon RNAs have been encapsulated by liposomes to improve delivery and targeting. Replicon RNA vectors have also been subjected to clinical trials. Overall, immunization with self-replicating RNA viruses provides high transient expression levels of antigens resulting in generation of neutralizing antibody responses and protection against lethal challenges under safe conditions. PMID:27827980

  3. Neuron-specific RNA interference using lentiviral vectors

    DEFF Research Database (Denmark)

    Nielsen, Troels Tolstrup; Marion, Ingrid van; Hasholt, Lis

    2009-01-01

    BACKGROUND: Viral vectors have been used in several different settings for the delivery of small hairpin (sh) RNAs. However, most vectors have utilized ubiquitously-expressing polymerase (pol) III promoters to drive expression of the hairpin as a result of the strict requirement for precise...... transcriptional initiation and termination. Recently, pol II promoters have been used to construct vectors for RNA interference (RNAi). By embedding the shRNA into a micro RNA-context (miRNA) the endogenous miRNA processing machinery is exploited to achieve the mature synthetic miRNA (smiRNA), thereby expanding...... the possible promoter choices and eventually allowing cell type specific down-regulation of target genes. METHODS: In the present study, we constructed lentiviral vectors expressing smiRNAs under the control of pol II promoters to knockdown gene expression in cell culture and in the brain. RESULTS: We...

  4. Biodegradable Multiamine Polymeric Vector for siRNA Delivery.

    Science.gov (United States)

    Yuan, Yuanyuan; Gong, Faming; Cao, Yang; Chen, Weicai; Cheng, Du; Shuai, Xintao

    2015-04-01

    The gene silencing activity of small interfering RNA (siRNA) has led to their use as tools for target validation and as potential therapeutics for a variety of diseases. A major challenge is the development of vectors with high delivery efficiency and low toxicity. Although poly(ethylenimine) (PEI) has been regarded as the most promising polymeric vector for nucleic acid delivery, the nonbiodegradable structure greatly hinders its clinical application. In the present study, a diblock copolymer, PEG-PAsp(DIP-DETA), of poly(ethylene glycol) (PEG) and poly(L-aspartic acid) (PAsp) randomly grafted with pH-sensitive 2-(diisopropylamino)ethylamine (DIP) and diethylenetriamine (DETA) groups was synthesized via ring-opening polymerization and aminolysis reaction. Similar to polyethylenimine (PEI), the copolymer possesses a multiamine structure that not only allows effective siRNA complexation at neutral pH but also facilitates lysosomal release of siRNA via a proton buffering effect. Moreover, the poly(L-aspartic acid) backbone renders the vector biodegradability, which is not achievable with PEI. This novel polymeric vector can mediate effective intracellular siRNA delivery in various cancer cells. Consequently, the delivery of BCL-2 siRNA resulted in target gene silencing, inducing apoptosis and inhibiting the growth of cancer cells. These results show the potential of this non-PEI based polymeric vector with proton buffering capacity and biodegradability for siRNA delivery in cancer therapy.

  5. Inducing RNA interference in the arbovirus vector, Culicoides sonorensis.

    Science.gov (United States)

    Mills, M K; Nayduch, D; Michel, K

    2015-02-01

    Biting midges in the genus Culicoides are important vectors of arboviral diseases, including epizootic haemorrhagic disease, bluetongue and most likely Schmallenberg, which cause significant economic burdens worldwide. Research on these vectors has been hindered by the lack of a sequenced genome, the difficulty of consistent culturing of certain species and the absence of molecular techniques such as RNA interference (RNAi). Here, we report the establishment of RNAi as a research tool for the adult midge, Culicoides sonorensis. Based on previous research and transcriptome analysis, which revealed putative small interfering RNA pathway member orthologues, we hypothesized that adult C. sonorensis midges have the molecular machinery needed to perform RNA silencing. Injection of control double-stranded RNA targeting green fluorescent protein (dsGFP), into the haemocoel of 2-3-day-old adult female midges resulted in survival curves that support virus transmission. dsRNA injection targeting the newly identified C. sonorensis inhibitor of apoptosis protein 1 (CsIAP1) orthologue resulted in a 40% decrease of transcript levels and 73% shorter median survivals as compared with dsGFP-injected controls. These results reveal the conserved function of IAP1. Importantly, they also demonstrate the feasibility of RNAi by dsRNA injection in adult midges, which will greatly facilitate studies of the underlying mechanisms of vector competence in C. sonorensis.

  6. RNA Interference in Insect Vectors for Plant Viruses

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    Surapathrudu Kanakala

    2016-12-01

    Full Text Available Insects and other arthropods are the most important vectors of plant pathogens. The majority of plant pathogens are disseminated by arthropod vectors such as aphids, beetles, leafhoppers, planthoppers, thrips and whiteflies. Transmission of plant pathogens and the challenges in managing insect vectors due to insecticide resistance are factors that contribute to major food losses in agriculture. RNA interference (RNAi was recently suggested as a promising strategy for controlling insect pests, including those that serve as important vectors for plant pathogens. The last decade has witnessed a dramatic increase in the functional analysis of insect genes, especially those whose silencing results in mortality or interference with pathogen transmission. The identification of such candidates poses a major challenge for increasing the role of RNAi in pest control. Another challenge is to understand the RNAi machinery in insect cells and whether components that were identified in other organisms are also present in insect. This review will focus on summarizing success cases in which RNAi was used for silencing genes in insect vector for plant pathogens, and will be particularly helpful for vector biologists.

  7. RNA Interference in Insect Vectors for Plant Viruses.

    Science.gov (United States)

    Kanakala, Surapathrudu; Ghanim, Murad

    2016-12-12

    Insects and other arthropods are the most important vectors of plant pathogens. The majority of plant pathogens are disseminated by arthropod vectors such as aphids, beetles, leafhoppers, planthoppers, thrips and whiteflies. Transmission of plant pathogens and the challenges in managing insect vectors due to insecticide resistance are factors that contribute to major food losses in agriculture. RNA interference (RNAi) was recently suggested as a promising strategy for controlling insect pests, including those that serve as important vectors for plant pathogens. The last decade has witnessed a dramatic increase in the functional analysis of insect genes, especially those whose silencing results in mortality or interference with pathogen transmission. The identification of such candidates poses a major challenge for increasing the role of RNAi in pest control. Another challenge is to understand the RNAi machinery in insect cells and whether components that were identified in other organisms are also present in insect. This review will focus on summarizing success cases in which RNAi was used for silencing genes in insect vector for plant pathogens, and will be particularly helpful for vector biologists.

  8. Lentivirus-expressed siRNA vectors against Alzheimer disease.

    Science.gov (United States)

    Peng, Kevin A; Masliah, Eliezer

    2010-01-01

    Amyloid precursor protein (APP) has been implicated in the pathogenesis of Alzheimer disease, and the accumulation of APP products ultimately leads to the familiar histopathological and clinical manifestations associated with this most common form of dementia. A protein that has been shown to promote APP accumulation is beta-secretase (beta-site APP cleaving enzyme 1, or BACE1), which is increased in the cerebrospinal fluid in those affected with Alzheimer disease. Through in vivo studies using APP transgenic mice, we demonstrated that decreasing the expression of BACE1 via lentiviral vector delivery of BACE1 siRNA has the potential for significantly reducing the cleavage of APP, accumulation of these products, and consequent neurodegeneration. As such, lentiviral-expressed siRNA against BACE1 is a therapeutic possibility in the treatment of Alzheimer disease. We detail the use of lentivirus-expressed siRNA as a method to ameliorate Alzheimer disease neuropathology in APP transgenic mice.

  9. A simple and robust vector-based shRNA expression system used for RNA interference.

    Directory of Open Access Journals (Sweden)

    Xue-jun Wang

    Full Text Available BACKGROUND: RNA interference (RNAi mediated by small interfering RNAs (siRNAs or short hairpin RNAs (shRNAs has become a powerful genetic tool for conducting functional studies. Previously, vector-based shRNA-expression strategies capable of inducing RNAi in viable cells have been developed, however, these vector systems have some disadvantages, either because they were error-prone or cost prohibitive. RESULTS: In this report we described the development of a simple, robust shRNA expression system utilizing 1 long oligonucleotide or 2 short oligonucleotides for half the cost of conventional shRNA construction methods and with a >95% cloning success rate. The shRNA loop sequence and stem structure were also compared and carefully selected for better RNAi efficiency. Furthermore, an easier strategy was developed based on isocaudomers which permit rapid combination of the most efficient promoter-shRNA cassettes. Finally, using this method, the conservative target sites for hepatitis B virus (HBV knockdown were systemically screened and HBV antigen expression shown to be successfully suppressed in the presence of connected multiple shRNAs both in vitro and in vivo. CONCLUSION: This novel design describes an inexpensive and effective way to clone and express single or multiple shRNAs from the same vector with the capacity for potent and effective silencing of target genes.

  10. Packaging of HCV-RNA into lentiviral vector

    Energy Technology Data Exchange (ETDEWEB)

    Caval, Vincent [INSERM U966, Universite Francois Rabelais de Tours, Faculte de Medecine, 10 Bd. Tonnelle, 37000 Tours (France); Piver, Eric [INSERM U966, Universite Francois Rabelais de Tours, Faculte de Medecine, 10 Bd. Tonnelle, 37000 Tours (France); Service de Biochimie et Biologie Moleculaire, CHRU de Tours (France); Ivanyi-Nagy, Roland; Darlix, Jean-Luc [LaboRetro, ENS-Lyon INSERM, U758, 46 Allee d' Italie, 69364 Lyon (France); Pages, Jean-Christophe, E-mail: jean-christophe.pages@univ-tours.fr [INSERM U966, Universite Francois Rabelais de Tours, Faculte de Medecine, 10 Bd. Tonnelle, 37000 Tours (France); Service de Biochimie et Biologie Moleculaire, CHRU de Tours (France)

    2011-11-04

    Highlights: Black-Right-Pointing-Pointer Description of HCV-RNA Core-D1 interactions. Black-Right-Pointing-Pointer In vivo evaluation of the packaging of HCV genome. Black-Right-Pointing-Pointer Determination of the role of the three basic sub-domains of D1. Black-Right-Pointing-Pointer Heterologous system involving HIV-1 vector particles to mobilise HCV genome. Black-Right-Pointing-Pointer Full length mobilisation of HCV genome and HCV-receptor-independent entry. -- Abstract: The advent of infectious molecular clones of Hepatitis C virus (HCV) has unlocked the understanding of HCV life cycle. However, packaging of the genomic RNA, which is crucial to generate infectious viral particles, remains poorly understood. Molecular interactions of the domain 1 (D1) of HCV Core protein and HCV RNA have been described in vitro. Since compaction of genetic information within HCV genome has hampered conventional mutational approach to study packaging in vivo, we developed a novel heterologous system to evaluate the interactions between HCV RNA and Core D1. For this, we took advantage of the recruitment of Vpr fusion-proteins into HIV-1 particles. By fusing HCV Core D1 to Vpr we were able to package and transfer a HCV subgenomic replicon into a HIV-1 based lentiviral vector. We next examined how deletion mutants of basic sub-domains of Core D1 influenced HCV RNA recruitment. The results emphasized the crucial role of the first and third basic regions of D1 in packaging. Interestingly, the system described here allowed us to mobilise full-length JFH1 genome in CD81 defective cells, which are normally refractory to HCV infection. This finding paves the way to an evaluation of the replication capability of HCV in various cell types.

  11. One-oligonucleotide method for constructing vectors for RNA interference

    Institute of Scientific and Technical Information of China (English)

    Carlos Fabian FLORES-JASSO; Ines VELAZQUEZ-QUESADA; Carlos LANDA-SOLIS; Andres A GUTIERREZ; Luis VACA

    2005-01-01

    Aim: To develop an easy, fast, automated, and inexpensive method for constructing short-hairpin-RNA cassettes for RNAi studies. Methods: Using single oligonucleotides, a variety of DNA cassettes for RNAi vectors were constructed in only few minutes in an automated manner. The cassettes, targeting the eGFP,were cloned into plasmids driven by RNA polymerase Ⅲ promoter H 1. Then, the plasmids were transfected into HeLa cells that were later infected with a recombinant adenovirus encoding the eGFP gene. The level of eGFP fluorescence was evaluated by confocal imaging and flow cytometry. Results: The plasmids constructed with the DNA cassettes made by the one-oligonucleotide method inhibited eGFP with different potencies, ranging from 55% to 75%. Conclusion: By using the method reported here, it is possible to simultaneously construct hundreds of different DNA cassettes for RNAi experiments in an inexpensive, automated way. This method will facilitate functional genomics studies on mammalian cells.

  12. A Novel Vector for Abundant Expression of Antisense RNA, Triplex-forming RNA and Ribozyme in vivo

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    For abundant expression of antisense RNA, triplex-forming RNA and Ribozyme in vivo, a novel vector pBSKneorU6' was constructed by PCR cloning. This vector contains the intact human snRNA U6 gene expression unit, yet replacing the 61-nt-sequence in the middle of U6 snRNA coding region with three restriction enzyme sites. Hela nuclear extract in vitro transcription experiments demonstrated that this vector can effectively express U6 mutant RNA. Containing neor at the same time, stably transfected pBSKneorU6' can be selected easily.

  13. RNA Transferring Vector-pRNA%RNA转移载体-pRNA

    Institute of Scientific and Technical Information of China (English)

    杨燕; 张正茂; 杨东亮

    2005-01-01

    pRNA(packaging RNA)是枯草杆菌噬菌体ψ29前衣壳上分离出的一种小RNA分子,它作为一种效应分子的天然生物载体,可以保护效应分子不被核酸外切酶降解,防止效应分子在体内的错误折叠.pRNA能够形成二聚体、三聚体和六聚体,因此pRNA不仅可以携带效应分子,而且可以同时携带配体分子,使效应分子具有明确的靶向性.pRNA作为新一代基因转移载体,具有非常强大的应用前景.

  14. Inhibition of avian leukosis virus replication by vector-based RNA interference

    Science.gov (United States)

    RNAi has recently emerged as a promising antiviral technique in vertebrates. To date, most studies have used exogenous short interfering RNAs (siRNAs) to inhibit viral replication, though vectors expressing short hairpin RNAs (shRNA-mirs) in the context of a modified endogenous micro-RNA (miRNA) are...

  15. Inducing RNA interference in the arbovirus vector, Culicoides sonorensis

    Science.gov (United States)

    Biting midges in the genus Culicoides are important vectors of arboviral diseases, including Epizootic Hemorrhagic Disease, Bluetongue, and likely Schmallenberg, which cause significant economic burden worldwide. Research on these vectors has been hindered by the lack of a sequenced genome, the diff...

  16. The role of RNA interference (RNAi) in arbovirus-vector interactions.

    Science.gov (United States)

    Blair, Carol D; Olson, Ken E

    2015-02-17

    RNA interference (RNAi) was shown over 18 years ago to be a mechanism by which arbovirus replication and transmission could be controlled in arthropod vectors. During the intervening period, research on RNAi has defined many of the components and mechanisms of this antiviral pathway in arthropods, yet a number of unexplored questions remain. RNAi refers to RNA-mediated regulation of gene expression. Originally, the term described silencing of endogenous genes by introduction of exogenous double-stranded (ds)RNA with the same sequence as the gene to be silenced. Further research has shown that RNAi comprises three gene regulation pathways that are mediated by small RNAs: the small interfering (si)RNA, micro (mi)RNA, and Piwi-interacting (pi)RNA pathways. The exogenous (exo-)siRNA pathway is now recognized as a major antiviral innate immune response of arthropods. More recent studies suggest that the piRNA and miRNA pathways might also have important roles in arbovirus-vector interactions. This review will focus on current knowledge of the role of the exo-siRNA pathway as an arthropod vector antiviral response and on emerging research into vector piRNA and miRNA pathway modulation of arbovirus-vector interactions. Although it is assumed that arboviruses must evade the vector's antiviral RNAi response in order to maintain their natural transmission cycles, the strategies by which this is accomplished are not well defined. RNAi is also an important tool for arthropod gene knock-down in functional genomics studies and in development of arbovirus-resistant mosquito populations. Possible arbovirus strategies for evasion of RNAi and applications of RNAi in functional genomics analysis and arbovirus transmission control will also be reviewed.

  17. The Role of RNA Interference (RNAi in Arbovirus-Vector Interactions

    Directory of Open Access Journals (Sweden)

    Carol D. Blair

    2015-02-01

    Full Text Available RNA interference (RNAi was shown over 18 years ago to be a mechanism by which arbovirus replication and transmission could be controlled in arthropod vectors. During the intervening period, research on RNAi has defined many of the components and mechanisms of this antiviral pathway in arthropods, yet a number of unexplored questions remain. RNAi refers to RNA-mediated regulation of gene expression. Originally, the term described silencing of endogenous genes by introduction of exogenous double-stranded (dsRNA with the same sequence as the gene to be silenced. Further research has shown that RNAi comprises three gene regulation pathways that are mediated by small RNAs: the small interfering (siRNA, micro (miRNA, and Piwi-interacting (piRNA pathways. The exogenous (exo-siRNA pathway is now recognized as a major antiviral innate immune response of arthropods. More recent studies suggest that the piRNA and miRNA pathways might also have important roles in arbovirus-vector interactions. This review will focus on current knowledge of the role of the exo-siRNA pathway as an arthropod vector antiviral response and on emerging research into vector piRNA and miRNA pathway modulation of arbovirus-vector interactions. Although it is assumed that arboviruses must evade the vector’s antiviral RNAi response in order to maintain their natural transmission cycles, the strategies by which this is accomplished are not well defined. RNAi is also an important tool for arthropod gene knock-down in functional genomics studies and in development of arbovirus-resistant mosquito populations. Possible arbovirus strategies for evasion of RNAi and applications of RNAi in functional genomics analysis and arbovirus transmission control will also be reviewed.

  18. Efficient downregulation of multiple mRNA targets with a single shRNA-expressing lentiviral vector.

    Science.gov (United States)

    Chumakov, Stepan P; Kravchenko, Julia E; Prassolov, Vladimir S; Frolova, Elena I; Chumakov, Peter M

    2010-05-01

    Gene silencing based on RNA interference is widely used in fundamental research and in practical applications. However, a commonly incomplete functional suppression represents a serious drawback of this technology. We describe a series of lentiviral vectors each containing a single or multiple shRNA-expression cassette(s) driven by a RNA-polymerase III specific promoter and localized within the 3'-LTR of the lentiviral DNA backbone. The vectors also contain an antibiotic-resistance gene that allows positive selection of recipient cells. The combined expression of three different shRNAs specific to a single mRNA was shown to improve dramatically the level of mRNA inhibition, while the use of three different RNA-polymerase III specific promoters avoids the loss of shRNA-expression cassettes through the homologous recombination. The vector system was used for successful simultaneous suppression of three related SESN1, SESN2 and SESN3 genes, which suggests its particular value for testing phenotypes of functionally redundant genes.

  19. Development of non-defective recombinant densovirus vectors for microRNA delivery in the invasive vector mosquito, Aedes albopictus

    Science.gov (United States)

    Liu, Peiwen; Li, Xiaocong; Gu, Jinbao; Dong, Yunqiao; Liu, Yan; Santhosh, Puthiyakunnon; Chen, Xiaoguang

    2016-01-01

    We previously reported that mosquito densoviruses (MDVs) are potential vectors for delivering foreign nucleic acids into mosquito cells. However, considering existing expression strategies, recombinant viruses would inevitably become replication-defective viruses and lose their ability for secondary transmission. The packaging limitations of the virion represent a barrier for the development of MDVs for viral paratransgenesis or as high-efficiency bioinsecticides. Herein, we report the development of a non-defective recombinant Aedes aegypti densovirus (AaeDV) miRNA expression system, mediated by an artificial intron, using an intronic miRNA expression strategy. We demonstrated that this recombinant vector could be used to overexpress endogenous miRNAs or to decrease endogenous miRNAs by generating antisense sponges to explore the biological functions of miRNAs. In addition, the vector could express antisense-miRNAs to induce efficient gene silencing in vivo and in vitro. The recombinant virus effectively self-replicated and retained its secondary transmission ability, similar to the wild-type virus. The recombinant virus was also genetically stable. This study demonstrated the first construction of a non-defective recombinant MDV miRNA expression system, which represents a tool for the functional analysis of mosquito genes and lays the foundation for the application of viral paratransgenesis for dengue virus control. PMID:26879823

  20. Development of non-defective recombinant densovirus vectors for microRNA delivery in the invasive vector mosquito, Aedes albopictus.

    Science.gov (United States)

    Liu, Peiwen; Li, Xiaocong; Gu, Jinbao; Dong, Yunqiao; Liu, Yan; Santhosh, Puthiyakunnon; Chen, Xiaoguang

    2016-02-16

    We previously reported that mosquito densoviruses (MDVs) are potential vectors for delivering foreign nucleic acids into mosquito cells. However, considering existing expression strategies, recombinant viruses would inevitably become replication-defective viruses and lose their ability for secondary transmission. The packaging limitations of the virion represent a barrier for the development of MDVs for viral paratransgenesis or as high-efficiency bioinsecticides. Herein, we report the development of a non-defective recombinant Aedes aegypti densovirus (AaeDV) miRNA expression system, mediated by an artificial intron, using an intronic miRNA expression strategy. We demonstrated that this recombinant vector could be used to overexpress endogenous miRNAs or to decrease endogenous miRNAs by generating antisense sponges to explore the biological functions of miRNAs. In addition, the vector could express antisense-miRNAs to induce efficient gene silencing in vivo and in vitro. The recombinant virus effectively self-replicated and retained its secondary transmission ability, similar to the wild-type virus. The recombinant virus was also genetically stable. This study demonstrated the first construction of a non-defective recombinant MDV miRNA expression system, which represents a tool for the functional analysis of mosquito genes and lays the foundation for the application of viral paratransgenesis for dengue virus control.

  1. Reversal of MDR1 gene-dependent multidrug resistance using short hairpin RNA expression vectors

    Institute of Scientific and Technical Information of China (English)

    GAN Hui-zhu; ZHENG De-ming; ZHANG Gui-zhen; ZHAO Ji-sheng; ZHANG Feng-chun; BU Li-sha; YANG Shao-juan; PIAO Song-lan; DU Zhen-wu; GAO Shen

    2005-01-01

    Background RNA interference using short hairpin RNA (shRNA) can mediate sequence-specific inhibition of gene expression in mammalian cells. A vector-based approach for synthesizing shRNA has been developed recently. Overexpression of P-glycoprotein (P-gp), the MDR1 gene product, confers multidrug resistance (MDR) to cancer cells. In this study, we reversed MDR using shRNA expression vectors in a multidrug-resistant human breast cancer cell line (MCF-7/AdrR). Methods The two shRNA expression vectors were constructed and introduced into MCF-7/AdrR cells. Expression of MDR1 mRNA was assessed by RT-PCR, and P-gp expression was determined by Western Blot and immunocytochemistry. Apoptosis and sensitization of the breast cancer cells to doxorubicin were quantified by flow cytometry and methyl thiazolyl tetrazolium (MTT) assays, respectively. Cellular daunorubicin accumulation was assayed by laser confocal scanning microscopy (LCSM). Statistical significance of differences in mean values was evaluated by Student's t tests. P<0.05 was considered statistically significant.Results In MCF-7/AdrA cells transfected with MDR1-A and MDR1-B shRNA expression vectors, RT-PCR showed that MDR1 mRNA expression was reduced by 40.9% (P<0.05), 30.1% (P<0.01) (transient transfection) and 37.6 % (P<0.05), 28.0% (P<0.01) (stable transfection), respectively. Western Blot and immunocytochemistry showed that P-gp expression was significantly and specifically inhibited. Resistance against doxorubicin was decreased from 162-fold to 109-fold (P<0.05), 54-fold (P<0.01) (transient transfection) and to 108-fold (P<0.05), 50-fold (P<0.01) (stable transfection). Furthermore, shRNA vectors significantly enhanced the cellular daunorubicin accumulation. The combination of shRNA vectors and doxorubicin significantly induced apoptosis in MCF-7/AdrR cells. Conclusions shRNA expression vectors effectively reduce MDR expression in a sustained fashion and can restore the sensitivity of drug-resistant cancer

  2. Construction and expression of SET gene and siRNA recombinant adenovirus vectors

    Institute of Scientific and Technical Information of China (English)

    Xu Bo-qun; Lu Pin-hong; Li Ying; Xue Kai; Li Mei; Ma Xiang; Diao Fei-yan; Cui Yu-gui; Liu Jia-yin

    2010-01-01

    Objective: To construct SET gene recombinant adenovirus vector and SET gene small interfering RNA (SiRNA) recombinant adenovirus vector for over-expression or knock-down of SET levels.Methods: The cDNA sequence of SET was cloned by reverse transcriptive polymerase chain reaction (RT-PCR) and the SET gene fragment was subcloned into adenovirus shuttle plasmid pAdTrack-CMV to construct the shuttle plasmid pAdTrack-SET. The shuttle plasmid pAdtrack-SET was transformed into BJ5183 cells with the adenoviral backbone pAdEasy-1 to obtain the homologous recombinant Ad-CMV-SET and the recombinant Ad-CMV-SET was packaged and amplified in the AD293 cells. The expression of SET in AD293 cells was detected by Western blot. In addition, we constructed SET gene SiRNA recombinant adenovirus vector (Ad-H1-SiRNA/SET) and its efficacy of knockdown of SET protein was detected in infected GC-2spd(ts) cells by Western blot. Results: The recombinant adenovirus vectors, both SET gene recombinant adenovirus vector Ad-CMV-SET and SET gene SiRNA recombinant adenovirus vector Ad-H1-SiRNA/SET, were proven to be constructed successfully by the evidence of endonulease digestion and sequencing. AD293 cells infected with either recombinant adenovirus vector of Ad-CMV-SET or Ad-H1-SiRNA/SET were observed to express GFP. The expression of SET protein was up-regulated significantly in AD293 cells infected with SET gene recombinant adenovirus vector. On the contrast, SET protein was significantly down-regulated in the GC-2spd(ts) cells infected with Ad-H1-SiRNA/SET (P<0.05) and the knockdown efficiency was approximately 50%-70%. Conclusion: The recombinant adenovirus vector Ad-CMV-SET and Ad-H1-SiRNA/SET were successfully constructed and effectively expressed in germ cells and somatic cells. It provides an experimental tool for further study of SET gene in the physiological and pathophysiological mechanism of reproduction-related diseases.

  3. High-throughput construction of intron-containing hairpin RNA vectors for RNAi in plants.

    Directory of Open Access Journals (Sweden)

    Pu Yan

    Full Text Available With the wide use of double-stranded RNA interference (RNAi for the analysis of gene function in plants, a high-throughput system for making hairpin RNA (hpRNA constructs is in great demand. Here, we describe a novel restriction-ligation approach that provides a simple but efficient construction of intron-containing hpRNA (ihpRNA vectors. The system takes advantage of the type IIs restriction enzyme BsaI and our new plant RNAi vector pRNAi-GG based on the Golden Gate (GG cloning. This method requires only a single PCR product of the gene of interest flanked with BsaI recognition sequence, which can then be cloned into pRNAi-GG at both sense and antisense orientations simultaneously to form ihpRNA construct. The process, completed in one tube with one restriction-ligation step, produced a recombinant ihpRNA with high efficiency and zero background. We demonstrate the utility of the ihpRNA constructs generated with pRNAi-GG vector for the effective silencing of various individual endogenous and exogenous marker genes as well as two genes simultaneously. This method provides a novel and high-throughput platform for large-scale analysis of plant functional genomics.

  4. Adenovirus Vector-Derived VA-RNA-Mediated Innate Immune Responses

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    Hiroyuki Mizuguchi

    2011-07-01

    Full Text Available The major limitation of the clinical use of replication-incompetent adenovirus (Ad vectors is the interference by innate immune responses, including induction of inflammatory cytokines and interferons (IFN, following in vivo application of Ad vectors. Ad vector-induced production of inflammatory cytokines and IFNs also results in severe organ damage and efficient induction of acquired immune responses against Ad proteins and transgene products. Ad vector-induced innate immune responses are triggered by the recognition of Ad components by pattern recognition receptors (PRRs. In order to reduce the side effects by Ad vector-induced innate immune responses and to develop safer Ad vectors, it is crucial to clarify which PRRs and which Ad components are involved in Ad vector-induced innate immune responses. Our group previously demonstrated that myeloid differentiating factor 88 (MyD88 and toll-like receptor 9 (TLR9 play crucial roles in the Ad vector-induced inflammatory cytokine production in mouse bone marrow-derived dendritic cells. Furthermore, our group recently found that virus associated-RNAs (VA-RNAs, which are about 160 nucleotide-long non-coding small RNAs encoded in the Ad genome, are involved in IFN production through the IFN-β promoter stimulator-1 (IPS-1-mediated signaling pathway following Ad vector transduction. The aim of this review is to highlight the Ad vector-induced innate immune responses following transduction, especially VA-RNA-mediated innate immune responses. Our findings on the mechanism of Ad vector-induced innate immune responses should make an important contribution to the development of safer Ad vectors, such as an Ad vector lacking expression of VA-RNAs.

  5. Construction and identification of lentiviral RNA interference vector of rat leptin receptor gene

    Institute of Scientific and Technical Information of China (English)

    Zhengjuan LIU; Jie BIAN; Yuchuan WANG; Yongli ZHAO; Dong YAN; Xiaoxia WANG

    2009-01-01

    Leptin resistance is a main mechanism of acquired childhood obesity, and the suppression of long form of leptin receptor (OBRb) gene expression in diet-induced obese rats indicates that the down-regulation of OBRb gene expression plays a pivotal role in the mechanism of leptin resistance. The aim of the present study was to construct the lentiviral RNA interference (RNAi) vector of rat OBRb gene and evaluate the effects of siRNA on silencing OBRb gene expression. The target sequence of siRNA-OBRb was designed, and the com-plementary DNA containing both sense and antisense oligonucleotides was synthesized. After phosphorylation and annealing, these double-stranded DNA was cloned to pRNA-lentivector-VGFP to construct pRNA-Lenti-OBRb-VGFP recombinants with U6-containing promoter, target sequence and Poly Ⅲ terminator. Then, the products were confirmed by electrophoresis and sequencing analy-sis, and the effects of RNAi on reducing gene expression were further confirmed by real-time polymerase chain reaction in transfected rat glioma cells expressing OBRb. The target sequence of siRNA-OBRb was successfully cloned to pRNA-lentivector-VGFE and the RNAi protocol specifically reduced the expression of OBRb mRNA by approximately 80% compared with controls in transfected rat glioma cells. The successful construction of rat lentivirus vectors expressing OBRb-specific shRNA may be useful for further investigation in vivo.

  6. Adenovirus vectors lacking virus-associated RNA expression enhance shRNA activity to suppress hepatitis C virus replication

    Science.gov (United States)

    Pei, Zheng; Shi, Guoli; Kondo, Saki; Ito, Masahiko; Maekawa, Aya; Suzuki, Mariko; Saito, Izumu; Suzuki, Tetsuro; Kanegae, Yumi

    2013-12-01

    First-generation adenovirus vectors (FG AdVs) expressing short-hairpin RNA (shRNA) effectively downregulate the expressions of target genes. However, this vector, in fact, expresses not only the transgene product, but also virus-associated RNAs (VA RNAs) that disturb cellular RNAi machinery. We have established a production method for VA-deleted AdVs lacking expression of VA RNAs. Here, we showed that the highest shRNA activity was obtained when the shRNA was inserted not at the popularly used E1 site, but at the E4 site. We then compared the activities of shRNAs against hepatitis C virus (HCV) expressed from VA-deleted AdVs or conventional AdVs. The VA-deleted AdVs inhibited HCV production much more efficiently. Therefore, VA-deleted AdVs were more effective than the currently used AdVs for shRNA downregulation, probably because of the lack of competition between VA RNAs and the shRNAs. These VA-deleted AdVs might enable more effective gene therapies for chronic hepatitis C.

  7. Vectores

    OpenAIRE

    2016-01-01

    Documento que contiene la explicación sobre las temáticas de Sistemas coordenados, Cantidades vectoriales y escalares, Algunas propiedades de los vectores, Componentes de un vector y vectores unitarios

  8. Engineering Cowpea Mosaic Virus RNA-2 into a vector to express heterologous proteins in plants

    NARCIS (Netherlands)

    Kodetham Gopinath,; Wellink, J.; Porta, C.; Taylor, K.M.; Lomonossoff, G.P.; Kammen, van A.

    2000-01-01

    series of new cowpea mosaic virus (CPMV) RNA-2-based expression vectors were designed. The jellyfish green fluorescent protein (GFP) was introduced between the movement protein (MP) and the large (L) coat protein or downstream of the small (S) coat protein. Release of the GFP inserted between the MP

  9. Construction of permanently inducible miRNA-based expression vectors using site-specific recombinases

    Directory of Open Access Journals (Sweden)

    Garwick-Coppens Sara E

    2011-11-01

    Full Text Available Abstract Background RNA interference (RNAi is a conserved gene silencing mechanism mediated by small inhibitory microRNAs (miRNAs. Promoter-driven miRNA expression vectors have emerged as important tools for delivering natural or artificially designed miRNAs to eukaryotic cells and organisms. Such systems can be used to query the normal or pathogenic functions of natural miRNAs or messenger RNAs, or to therapeutically silence disease genes. Results As with any molecular cloning procedure, building miRNA-based expression constructs requires a time investment and some molecular biology skills. To improve efficiency and accelerate the construction process, we developed a method to rapidly generate miRNA expression vectors using recombinases instead of more traditional cut-and-paste molecular cloning techniques. In addition to streamlining the construction process, our cloning strategy provides vectors with added versatility. In our system, miRNAs can be constitutively expressed from the U6 promoter, or inducibly expressed by Cre recombinase. We also engineered a built-in mechanism to destroy the vector with Flp recombinase, if desired. Finally, to further simplify the construction process, we developed a software package that automates the prediction and design of optimal miRNA sequences using our system. Conclusions We designed and tested a modular system to rapidly clone miRNA expression cassettes. Our strategy reduces the hands-on time required to successfully generate effective constructs, and can be implemented in labs with minimal molecular cloning expertise. This versatile system provides options that permit constitutive or inducible miRNA expression, depending upon the needs of the end user. As such, it has utility for basic or translational applications.

  10. Adenovirus vector-mediated RNA interference for the inhibition of human parvovirus B19 replication.

    Science.gov (United States)

    Brandt, Marius R G; Kirste, Ariane G; Pozzuto, Tanja; Schubert, Steffen; Kandolf, Reinhard; Fechner, Henry; Bock, C-Thomas; Kurreck, Jens

    2013-09-01

    Human parvovirus B19 (B19V) has been considered to cause acute and chronic myocarditis, which is accompanied by endothelial dysfunction. Currently, no causative treatment option for B19V-infections is available. Since RNA interference (RNAi) has proven to be a highly potent antiviral approach, the aim of the current study was to develop an RNAi-based strategy to inhibit B19V replication. Three B19V-VP2-specific short hairpin RNAs (shRNAs) were designed and tested for their silencing activity in reporter assays and the expression cassette of the best one was introduced into an adenoviral shuttle vector (Ad5). B19V-permissive UT7/Epo-S1 cells were infected with B19V and the RNAi triggers were delivered by the adenoviral vector (Ad5shVP2) 24h thereafter. The shRNA targeting the B19V-VP2 gene significantly suppressed VP2 mRNA levels as determined by quantitative RT-PCR. Additionally, also the expression levels of the non-targeted non-structural B19V-NS1 mRNA were strongly reduced. Our results demonstrate that vector-mediated delivery of shRNA expression cassettes targeting the structural B19-VP2 gene is a suitable approach to inhibit B19V replication.

  11. [Construction and identification of small interfering RNA expression vector targeting ATF-2 gene].

    Science.gov (United States)

    Mao, Wei-wei; Xiong, Peng; Han, Feng; Hu, Zhi-jian

    2012-09-01

    To construct an eukaryotic expression vector for RNA interference targeting activating transcription factor 2 (ATF-2) gene, and explore its effect on proliferation and apoptosis of HepG2 cells. Two complementary oligonucleotides were synthesized based on ATF-2 mRNA sequence. The annealed fragment was inserted into the vector PBA-siU6. The recombinant plasmid PBA-siATF-2 was confirmed by DNA sequencing and transfected into HepG2 cells mediated by liposome. After transfection, ATF-2 protein was detected by Western blotting. The cellular growth activity and apoptosis rate were measured by MTT assay and flow cytometry, respectively. Recombinant plasmid expressing siRNA targeting ATF-2 gene was confirmed by DNA sequencing. Plasmid transfection down-regulated the level of ATF-2 protein in HepG2 cells, which blocked cellular growth and induced cell apoptosis. The eukaryotic expression vector for RNA interference targeting ATF-2 gene was constructed successfully, which inhibits HepG2 cell proliferation and induces cell apoptosis.

  12. Construction of an Artificial MicroRNA Expression Vector for Simultaneous Inhibition of Multiple Genes in Mammalian Cells

    Directory of Open Access Journals (Sweden)

    Deyin Guo

    2009-05-01

    Full Text Available Recently, artificial microRNA (amiRNA has become a promising RNA interference (RNAi technology. Here, we describe a flexible and reliable method for constructing both single- and multi-amiRNA expression vectors. Two universal primers, together with two specific primers carrying the encoding sequence of amiRNA were designed and utilized to synthesize the functional amiRNA cassette through a one-step PCR. With appropriate restriction sites, the synthesized amiRNA cassettes can be cloned into any site of different destination vectors. Using the method, we constructed both single- and multi-amiRNA expression vectors to target three reporter genes, which code firefly luciferase (Fluc, enhanced green fluorescent protein (EGFP and β-galactosidase (LacZ, respectively. The expressions of three genes were all specifically inhibited by either the corresponding single- or the multi-amiRNA expression vector in 293T cells. And the RNAi efficiency of each amiRNA produced by both single- and multi-amiRNA expression vectors was comparable.

  13. Construction of a vector generating both siRNA and a fluorescent reporter: a siRNA study in cultured neurons.

    Science.gov (United States)

    Yoon, Seung Yong; Choi, Jung Eun; Hwang, Onyou; Hong, Hea Nam; Lee, Heuiran; Kim, Yoo Kyum; Cho, Sung-Woo; Kim, Hyun; Kim, DongHou

    2004-08-31

    RNA interference is an important tool for gene silencing. However, its application to primary cultured cells has been limited by low transfection efficiencies. In this work we developed a vector which encodes both siRNA and red fluorescent protein. Using this vector we could markedly suppress green fluorescent protein (GFP) and bim an endogenous gene. Primary cultured cortical neurons transfected with siRNA against doublecortin showed that doublecortin expression was significantly inhibited in nearly all the transfected neurons. This vector identifies the transfected cells and should be useful for loss-of-gene function studies in neurons.

  14. Chitosan Hydrogel as siRNA vector for prolonged gene silencing

    Science.gov (United States)

    2014-01-01

    Background The periodontitis is one of the most prevalent diseases with alveolar resorption in adult people and is the main cause of the tooth loss. To investigate the possibility for protecting the loss of alveolar bone in periodontal diseases, a RNAi-based therapeutic strategy is applied for silencing RANK signaling using thermosensitive chitosan hydrogel as siRNA reservoir and vector. Results The thermosensitive chitosan hydrogel was formed from solution (PH = 7.2, at 4°C) at 37°C within 8 minutes. The degradation rates of hydrogel were ~50% and 5% (W remaining/W beginning) in the presence and absence of lysozyme, respectively, over a period of 20 days. The concurrent cumulative in vitro release of Cy3-labeled siRNA from the hydrogel was 50% and 17% over 14 days, with or without lysozyme digestion, respectively. High cell viability (>88%) was maintained for cells treated with hydrogel loaded with RANK specific siRNA and RANK knockdown was prolonged for up to 9 days when cells were incubated with siRNA/hydrogel complex. In vivo release of siRNA was investigated in a subcutaneous delivery setup in mice. The fluorescent signal from siRNA within hydrogel was remained for up to 14 days compared to less than one day for siRNA alone. Conclusions Chitosan hydrogel can potentially serve as a suitable reservoir and vector for local sustained delivery of siRNA in potential therapy. PMID:24946934

  15. Expression of IMP1 enhances production of murine leukemia virus vector by facilitating viral genomic RNA packaging.

    Directory of Open Access Journals (Sweden)

    Yun Mai

    Full Text Available Murine leukemia virus (MLV-based retroviral vector is widely used for gene transfer. Efficient packaging of the genomic RNA is critical for production of high-titer virus. Here, we report that expression of the insulin-like growth factor II mRNA binding protein 1 (IMP1 enhanced the production of infectious MLV vector. Overexpression of IMP1 increased the stability of viral genomic RNA in virus producer cells and packaging of the RNA into progeny virus in a dose-dependent manner. Downregulation of IMP1 in virus producer cells resulted in reduced production of the retroviral vector. These results indicate that IMP1 plays a role in regulating the packaging of MLV genomic RNA and can be used for improving production of retroviral vectors.

  16. Expression of IMP1 enhances production of murine leukemia virus vector by facilitating viral genomic RNA packaging.

    Science.gov (United States)

    Mai, Yun; Gao, Guangxia

    2010-12-29

    Murine leukemia virus (MLV)-based retroviral vector is widely used for gene transfer. Efficient packaging of the genomic RNA is critical for production of high-titer virus. Here, we report that expression of the insulin-like growth factor II mRNA binding protein 1 (IMP1) enhanced the production of infectious MLV vector. Overexpression of IMP1 increased the stability of viral genomic RNA in virus producer cells and packaging of the RNA into progeny virus in a dose-dependent manner. Downregulation of IMP1 in virus producer cells resulted in reduced production of the retroviral vector. These results indicate that IMP1 plays a role in regulating the packaging of MLV genomic RNA and can be used for improving production of retroviral vectors.

  17. Vectors

    DEFF Research Database (Denmark)

    Boeriis, Morten; van Leeuwen, Theo

    2017-01-01

    This article revisits the concept of vectors, which, in Kress and van Leeuwen’s Reading Images (2006), plays a crucial role in distinguishing between ‘narrative’, action-oriented processes and ‘conceptual’, state-oriented processes. The use of this concept in image analysis has usually focused...... on the most salient vectors, and this works well, but many images contain a plethora of vectors, which makes their structure quite different from the linguistic transitivity structures with which Kress and van Leeuwen have compared ‘narrative’ images. It can also be asked whether facial expression vectors...... should be taken into account in discussing ‘reactions’, which Kress and van Leeuwen link only to eyeline vectors. Finally, the question can be raised as to whether actions are always realized by vectors. Drawing on a re-reading of Rudolf Arnheim’s account of vectors, these issues are outlined...

  18. Cooler temperatures destabilize RNA interference and increase susceptibility of disease vector mosquitoes to viral infection.

    Directory of Open Access Journals (Sweden)

    Zach N Adelman

    Full Text Available BACKGROUND: The impact of global climate change on the transmission dynamics of infectious diseases is the subject of extensive debate. The transmission of mosquito-borne viral diseases is particularly complex, with climatic variables directly affecting many parameters associated with the prevalence of disease vectors. While evidence shows that warmer temperatures often decrease the extrinsic incubation period of an arthropod-borne virus (arbovirus, exposure to cooler temperatures often predisposes disease vector mosquitoes to higher infection rates. RNA interference (RNAi pathways are essential to antiviral immunity in the mosquito; however, few experiments have explored the effects of temperature on the RNAi machinery. METHODOLOGY/PRINCIPAL FINDINGS: We utilized transgenic "sensor" strains of Aedes aegypti to examine the role of temperature on RNA silencing. These "sensor" strains express EGFP only when RNAi is inhibited; for example, after knockdown of the effector proteins Dicer-2 (DCR-2 or Argonaute-2 (AGO-2. We observed an increase in EGFP expression in transgenic sensor mosquitoes reared at 18°C as compared with 28°C. Changes in expression were dependent on the presence of an inverted repeat with homology to a portion of the EGFP sequence, as transgenic strains lacking this sequence, the double stranded RNA (dsRNA trigger for RNAi, showed no change in EGFP expression when reared at 18°C. Sequencing small RNAs in sensor mosquitoes reared at low temperature revealed normal processing of dsRNA substrates, suggesting the observed deficiency in RNAi occurs downstream of DCR-2. Rearing at cooler temperatures also predisposed mosquitoes to higher levels of infection with both chikungunya and yellow fever viruses. CONCLUSIONS/SIGNIFICANCE: This data suggest that microclimates, such as those present in mosquito breeding sites, as well as more general climactic variables may influence the dynamics of mosquito-borne viral diseases by affecting

  19. Engineering and Validation of a Vector for Concomitant Expression of Rare Transfer RNA (tRNA) and HIV-1 nef Genes in Escherichia coli.

    Science.gov (United States)

    Mualif, Siti Aisyah; Teow, Sin-Yeang; Omar, Tasyriq Che; Chew, Yik Wei; Yusoff, Narazah Mohd; Ali, Syed A

    2015-01-01

    Relative ease in handling and manipulation of Escherichia coli strains make them primary candidate to express proteins heterologously. Overexpression of heterologous genes that contain codons infrequently used by E. coli is related with difficulties such as mRNA instability, early termination of transcription and/or translation, deletions and/or misincorporation, and cell growth inhibition. These codon bias -associated problems are addressed by co-expressing ColE1-compatible, rare tRNA expressing helper plasmids. However, this approach has inadequacies, which we have addressed by engineering an expression vector that concomitantly expresses the heterologous protein of interest, and rare tRNA genes in E. coli. The expression vector contains three (argU, ileY, leuW) rare tRNA genes and a useful multiple cloning site for easy in-frame cloning. To maintain the overall size of the parental plasmid vector, the rare tRNA genes replaced the non-essential DNA segments in the vector. The cloned gene is expressed under the control of T7 promoter and resulting recombinant protein has a C-terminal 6His tag for IMAC-mediated purification. We have evaluated the usefulness of this expression vector by expressing three HIV-1 genes namely HIV-1 p27 (nef), HIV-1 p24 (ca), and HIV-1 vif in NiCo21(DE3) E.coli and demonstrated the advantages of using expression vector that concomitantly expresses rare tRNA and heterologous genes.

  20. Multigenic lentiviral vectors for combined and tissue-specific expression of miRNA- and protein-based antiangiogenic factors

    DEFF Research Database (Denmark)

    Askou, Anne Louise; Aagaard, Lars; Kostic, Corinne

    2015-01-01

    Lentivirus-based gene delivery vectors carrying multiple gene cassettes are powerful tools in gene transfer studies and gene therapy, allowing coexpression of multiple therapeutic factors and, if desired, fluorescent reporters. Current strategies to express transgenes and microRNA (miRNA) clusters......-to-back RNApolII-driven expression cassettes. This configuration allows effective production of intron-embedded miRNAs that are released upon transduction of target cells. Exploiting such multigenic lentiviral vectors, we demonstrate robust miRNA-directed downregulation of vascular endothelial growth factor...... by the VMD2 promoter, verifying that multigenic lentiviral vectors can be produced with high titers sufficient for in vivo applications. Altogether, our results suggest the potential applicability of combined miRNA- and protein-encoding lentiviral vectors in antiangiogenic gene therapy, including new...

  1. Efficient production of superior dumbbell-shaped DNA minimal vectors for small hairpin RNA expression.

    Science.gov (United States)

    Yu, Han; Jiang, Xiaoou; Tan, Kar Tong; Hang, Liting; Patzel, Volker

    2015-10-15

    Genetic therapy holds great promise for the treatment of inherited or acquired genetic diseases; however, its breakthrough is hampered by the lack of suitable gene delivery systems. Dumbbell-shaped DNA minimal vectors represent an attractive, safe alternative to the commonly used viral vectors which are fraught with risk, but dumbbell generation appears to be costly and time-consuming. We developed a new PCR-based method for dumbbell production which comprises only two steps. First, PCR amplification of the therapeutic expression cassette using chemically modified primers to form a ready-to-ligate DNA structure; and second, a highly efficient intramolecular ligation reaction. Compared with conventional strategies, the new method produces dumbbell vectors more rapidly, with higher yields and purity, and at lower costs. In addition, such produced small hairpin RNA expressing dumbbells triggered superior target gene knockdown compared with conventionally produced dumbbells or plasmids. Our novel method is suitable for large-scale dumbbell production and can facilitate clinical applications of this vector system.

  2. Double-stranded RNA transcribed from vector-based oligodeoxynucleotide acts as transcription factor decoy

    Energy Technology Data Exchange (ETDEWEB)

    Xiao, Xiao [State Key Laboratory of Cancer Biology and Xijing Hospital of Digestive Diseases, Xijing Hospital, Fourth Military Medical University, Xi’an 710032, Shaanxi Province (China); Gang, Yi [State Key Laboratory of Cancer Biology and Xijing Hospital of Digestive Diseases, Xijing Hospital, Fourth Military Medical University, Xi’an 710032, Shaanxi Province (China); Department of Infectious Diseases, Tangdu Hospital, Fourth Military Medical University, Xi’an 710038, Shaanxi Province (China); Wang, Honghong [No. 518 Hospital of Chinese People’s Liberation Army, Xi’an 710043, Shaanxi Province (China); Wang, Jiayin [The Genome Institute, Washington University in St. Louis, St. Louis, MO 63108 (United States); Zhao, Lina [Department of Radiation Oncology, Xijing Hospital, Fourth Military Medical University, Xi’an 710032, Shaanxi Province (China); Xu, Li, E-mail: lxuhelen@163.com [State Key Laboratory of Cancer Biology and Xijing Hospital of Digestive Diseases, Xijing Hospital, Fourth Military Medical University, Xi’an 710032, Shaanxi Province (China); Liu, Zhiguo, E-mail: liuzhiguo@fmmu.edu.cn [State Key Laboratory of Cancer Biology and Xijing Hospital of Digestive Diseases, Xijing Hospital, Fourth Military Medical University, Xi’an 710032, Shaanxi Province (China)

    2015-02-06

    Highlights: • A shRNA vector based transcription factor decoy, VB-ODN, was designed. • VB-ODN for NF-κB inhibited cell viability in HEK293 cells. • VB-ODN inhibited expression of downstream genes of target transcription factors. • VB-ODN may enhance nuclear entry ratio for its feasibility of virus production. - Abstract: In this study, we designed a short hairpin RNA vector-based oligodeoxynucleotide (VB-ODN) carrying transcription factor (TF) consensus sequence which could function as a decoy to block TF activity. Specifically, VB-ODN for Nuclear factor-κB (NF-κB) could inhibit cell viability and decrease downstream gene expression in HEK293 cells without affecting expression of NF-κB itself. The specific binding between VB-ODN produced double-stranded RNA and NF-κB was evidenced by electrophoretic mobility shift assay. Moreover, similar VB-ODNs designed for three other TFs also inhibit their downstream gene expression but not that of themselves. Our study provides a new design of decoy for blocking TF activity.

  3. Construction of the human miRNA-451 expression vector and its expression in gastric carcinoma cell line SGC-7901*

    Institute of Scientific and Technical Information of China (English)

    Biao Chen; Ximing Xu

    2013-01-01

    Objective:The aim of the study was to construct miRNA-451 expression vector pLMP-miRNA-451 which could help identify the functions of miRNA-451 in SGC-7901 cel . Methods:Total RNA was extracted from SGC-7901 cel s to synthesized cDNA. The synthesized cDNA encoding pre-miRNA-451 was amplified by polymerase chain reaction (PCR). The PCR product was separated by electrophoresis on 1%agarose gel and then recovered and purified. The purified cDNA fragments of miRNA-451 precursor sequence was then ligated with vector pLMP for 1 h by using DNA ligase to form pLMP-miRNA-451 plasmid. After that, the pLMP-miRNA-451 plasmid was transformed into E. coli DH5αstrain expression system to clone and amplificate. The purified pLMP-miRNA-451 extracted from E. coli DH5αvia transformation and clone screening was identificatied with restriction enzyme digestion and DNA sequencing. At last, pLMP-miRNA-451 was transfected into SGC-7901 cel s with lip2000. Real-time PCR was used for detection of the miRNA-451, the transfection ef iciency was ob-served under fluorescence microscopy and cel counting kit-8 assay was conduced to evaluate the ef ect of miRNA-451 on SGC-7901 cel proliferation. Results:Our results showed that pLMP-miRNA-451 expression vector was not only constructed successful y and ef ectively infected SGC-7901 cel s, but also could repress the SGC-7901 cel proliferation. Conclusion:The constructed plasmid pLMP-miRNA-451 could used for further studies of miRNA-451 in SGC-7901 cel lines.

  4. miRNA genes of an invasive vector mosquito, Aedes albopictus.

    Directory of Open Access Journals (Sweden)

    Jinbao Gu

    Full Text Available Aedes albopictus, a vector of Dengue and Chikungunya viruses, is a robust invasive species in both tropical and temperate environments. MicroRNAs (miRNAs regulate gene expression and biological processes including embryonic development, innate immunity and infection. While a number of miRNAs have been discovered in some mosquitoes, no comprehensive effort has been made to characterize them from different developmental stages from a single species. Systematic analysis of miRNAs in Ae. albopictus will improve our understanding of its basic biology and inform novel strategies to prevent virus transmission. Between 10-14 million Illumina sequencing reads per sample were obtained from embryos, larvae, pupae, adult males, sugar-fed and blood-fed adult females. A total of 119 miRNA genes represented by 215 miRNA or miRNA star (miRNA* sequences were identified, 15 of which are novel. Eleven, two, and two of the newly-discovered miRNA genes appear specific to Aedes, Culicinae, and Culicidae, respectively. A number of miRNAs accumulate predominantly in one or two developmental stages and the large number that showed differences in abundance following a blood meal likely are important in blood-induced mosquito biology. Gene Ontology (GO analysis of the targets of all Ae. albopictus miRNAs provides a useful starting point for the study of their functions in mosquitoes. This study is the first systematic analysis of miRNAs based on deep-sequencing of small RNA samples of all developmental stages of a mosquito species. A number of miRNAs are related to specific physiological states, most notably, pre- and post-blood feeding. The distribution of lineage-specific miRNAs is consistent with mosquito phylogeny and the presence of a number of Aedes-specific miRNAs likely reflects the divergence between the Aedes and Culex genera.

  5. miRNA genes of an invasive vector mosquito, Aedes albopictus.

    Science.gov (United States)

    Gu, Jinbao; Hu, Wanqi; Wu, Jinya; Zheng, Peiming; Chen, Maoshan; James, Anthony A; Chen, Xiaoguang; Tu, Zhijian

    2013-01-01

    Aedes albopictus, a vector of Dengue and Chikungunya viruses, is a robust invasive species in both tropical and temperate environments. MicroRNAs (miRNAs) regulate gene expression and biological processes including embryonic development, innate immunity and infection. While a number of miRNAs have been discovered in some mosquitoes, no comprehensive effort has been made to characterize them from different developmental stages from a single species. Systematic analysis of miRNAs in Ae. albopictus will improve our understanding of its basic biology and inform novel strategies to prevent virus transmission. Between 10-14 million Illumina sequencing reads per sample were obtained from embryos, larvae, pupae, adult males, sugar-fed and blood-fed adult females. A total of 119 miRNA genes represented by 215 miRNA or miRNA star (miRNA*) sequences were identified, 15 of which are novel. Eleven, two, and two of the newly-discovered miRNA genes appear specific to Aedes, Culicinae, and Culicidae, respectively. A number of miRNAs accumulate predominantly in one or two developmental stages and the large number that showed differences in abundance following a blood meal likely are important in blood-induced mosquito biology. Gene Ontology (GO) analysis of the targets of all Ae. albopictus miRNAs provides a useful starting point for the study of their functions in mosquitoes. This study is the first systematic analysis of miRNAs based on deep-sequencing of small RNA samples of all developmental stages of a mosquito species. A number of miRNAs are related to specific physiological states, most notably, pre- and post-blood feeding. The distribution of lineage-specific miRNAs is consistent with mosquito phylogeny and the presence of a number of Aedes-specific miRNAs likely reflects the divergence between the Aedes and Culex genera.

  6. Design, Construction, and Validation of Artificial MicroRNA Vectors Using Agrobacterium-Mediated Transient Expression System.

    Science.gov (United States)

    Bhagwat, Basdeo; Chi, Ming; Han, Dianwei; Tang, Haifeng; Tang, Guiliang; Xiang, Yu

    2016-01-01

    Artificial microRNA (amiRNA) technology utilizes microRNA (miRNA) biogenesis pathway to produce artificially selected small RNAs using miRNA gene backbone. It provides a feasible strategy for inducing loss of gene function, and has been applied in functional genomics study, improvement of crop quality and plant virus disease resistance. A big challenge in amiRNA applications is the unpredictability of silencing efficacy of the designed amiRNAs and not all constructed amiRNA candidates would be expressed effectively in plant cells. We and others found that high efficiency and specificity in RNA silencing can be achieved by designing amiRNAs with perfect or almost perfect sequence complementarity to their targets. In addition, we recently demonstrated that Agrobacterium-mediated transient expression system can be used to validate amiRNA constructs, which provides a simple, rapid and effective method to select highly expressible amiRNA candidates for stable genetic transformation. Here, we describe the methods for design of amiRNA candidates with perfect or almost perfect base-pairing to the target gene or gene groups, incorporation of amiRNA candidates in miR168a gene backbone by one step inverse PCR amplification, construction of plant amiRNA expression vectors, and assay of transient expression of amiRNAs in Nicotiana benthamiana through agro-infiltration, small RNA extraction, and amiRNA Northern blot.

  7. Engineering and Validation of a Vector for Concomitant Expression of Rare Transfer RNA (tRNA and HIV-1 nef Genes in Escherichia coli.

    Directory of Open Access Journals (Sweden)

    Siti Aisyah Mualif

    Full Text Available Relative ease in handling and manipulation of Escherichia coli strains make them primary candidate to express proteins heterologously. Overexpression of heterologous genes that contain codons infrequently used by E. coli is related with difficulties such as mRNA instability, early termination of transcription and/or translation, deletions and/or misincorporation, and cell growth inhibition. These codon bias -associated problems are addressed by co-expressing ColE1-compatible, rare tRNA expressing helper plasmids. However, this approach has inadequacies, which we have addressed by engineering an expression vector that concomitantly expresses the heterologous protein of interest, and rare tRNA genes in E. coli. The expression vector contains three (argU, ileY, leuW rare tRNA genes and a useful multiple cloning site for easy in-frame cloning. To maintain the overall size of the parental plasmid vector, the rare tRNA genes replaced the non-essential DNA segments in the vector. The cloned gene is expressed under the control of T7 promoter and resulting recombinant protein has a C-terminal 6His tag for IMAC-mediated purification. We have evaluated the usefulness of this expression vector by expressing three HIV-1 genes namely HIV-1 p27 (nef, HIV-1 p24 (ca, and HIV-1 vif in NiCo21(DE3 E.coli and demonstrated the advantages of using expression vector that concomitantly expresses rare tRNA and heterologous genes.

  8. Boiler: lossy compression of RNA-seq alignments using coverage vectors.

    Science.gov (United States)

    Pritt, Jacob; Langmead, Ben

    2016-09-19

    We describe Boiler, a new software tool for compressing and querying large collections of RNA-seq alignments. Boiler discards most per-read data, keeping only a genomic coverage vector plus a few empirical distributions summarizing the alignments. Since most per-read data is discarded, storage footprint is often much smaller than that achieved by other compression tools. Despite this, the most relevant per-read data can be recovered; we show that Boiler compression has only a slight negative impact on results given by downstream tools for isoform assembly and quantification. Boiler also allows the user to pose fast and useful queries without decompressing the entire file. Boiler is free open source software available from github.com/jpritt/boiler.

  9. Constructionof the recombinant adenovirus vectors of CALB2 gene and small interfering RNA, and application in testicular Leydig cells

    Institute of Scientific and Technical Information of China (English)

    Luo Jian; Wang Jing; Liu Shan; Sun Xue-ping; Gao Chao; Gao Li; Yang Xiao-yu; Liu Jia-yin; Cui Yu-gui

    2011-01-01

    Objective:To construct the recombinant adenovirus vectors of calretinin (CALB2) gene and small interfering RNA (siRNA),for over-expression or knock-down of CALB2,as the basis of functional investigation of CALB2 in testicular Leydig cells.Methods:The cDNA sequence of CALB2 was cloned by the reverse transcriptive polymerase chain reaction (RT-PCR).A CALB2 gene fragment was sub-cloned into adenovirus shuttle plasmid pAdTrack-CMV to construct the shuttle plasmid pAdTrack-CALB2.Then it was transformed into BJ5183 cells with the adenoviral backbone pAdEasy-1 to obtain the homologous recombinant AdCMV-CALB2.The recombinant AdCMV-CALB2 was further packaged and amplificated in AD293 cells.The expression of CALB2 protein in AD293 cells was detected by Western blotting.CALB2 protein was over-expressed in mouse Leydig cell line (MLTC-1 cells) by the constructed AdCMVCALB2.CALB2 gene siRNA recombinant adenovirus vector (Ad-H1-siRNA/CALB2 was also constructed simultaneously.Its efficacy was detected in AD293 cells by Western blotting.Results:The CALB2 gene recombinant adenovirus vector AdCMV-CALB2 and the CALB2 gene siRNA recombinant adenovirus vector Ad-H1-siRNA/CALB2 were constructed successfully by endonulease digestion and sequencing.AD293 cells infected with AdCMV-CALB2 or Ad-H1-SiRNA/CALB2 significantly expressed GFP protein.The expression of CALB2 protein was significantly up-regulated in AD293 cells infected with AdCMV-CALB2 plasmids,while the expression of CALB2 protein was down-regulated by 60% in the CALB2 cells infected with Ad-H1SiRNA/CALB2.MLTC-1 cells did not markedly express CALLB2 protein,while MLTC-1 cells infected with AdCMV-CALB2 expressed CALB2 protein at a high level.Conclusions:The recombinant adenovirus vectors of AdCMV-CALB2 and Ad-H1-SiRNA/CALB2 were successfully constructed.Both vectors effectively expressed in AD293.CALB2 protein was over-expressed in the cultured MLTC-1 cells by AdCMV-CALB2.These vectors of CALB2 gene and Leydig cell line are

  10. A single-plasmid vector for transgene amplification using short hairpin RNA targeting the 3'-UTR of amplifiable dhfr.

    Science.gov (United States)

    Kang, Shin-Young; Kim, Yeon-Gu; Lee, Hong Weon; Lee, Eun Gyo

    2015-12-01

    Gene amplification using dihydrofolate reductase gene (dhfr) and methotrexate (MTX) is widely used for recombinant protein production in mammalian cells and is typically conducted in DHFR-deficient Chinese hamster ovary (CHO) cell lines. Generation of DHFR-deficient cells can be achieved by an expression vector incorporating short hairpin RNA (shRNA) that targets the 3'-untranslated region (UTR) of endogenous dhfr. Thus, shRNAs were designed to target the 3'-UTR of endogenous dhfr, and shRNA-2 efficiently down-regulated dhfr expression in CHO-K1 cells. A single gene copy of shRNA-2 also decreased the translational level of DHFR by 80% in Flp-In CHO cells. shRNA-2 was then incorporated into a plasmid vector expressing human erythropoietin (EPO) and an exogenous DHFR to develop EPO-producing cells in the Flp-In system. The specific EPO productivity (q EPO) was enhanced by stepwise increments of MTX concentration, and differences in the amplification rate were observed in Flp-In CHO cells that expressed shRNA-2. In addition, the q EPO increased by more than 2.5-fold in the presence of 500 nM MTX. The mRNA expression level and gene copy numbers of dhfr were correlated with increased productivity in the cells, which is influenced by inhibition of endogenous dhfr. This study reveals that an expression vector including shRNA that targets the 3'-UTR of endogenous dhfr can enhance the transgene amplification rate and productivity by generating DHFR-deficient cells. This approach may be applied for amplifying the foreign gene in wild-type cell lines as a versatile single-plasmid vector.

  11. Construction and Characterization of Lentiviral shRNA Expression Vector Targeting Rat CD40 Gene in Dendritic Cells

    Institute of Scientific and Technical Information of China (English)

    SUN Mei; LI Jin-dong; JIANG Rui; JIN Cheng-yan; GAO Nan; LUO Shu-li; WANG Chun-guang; WANG Bin; WANG Rong-you; ZHANG Xing-yi

    2009-01-01

    To construct a lentiviral shRNA vector targeting rat CD40 gene and detect its effectiveness of gene silencing in dendritic cells(DCs), specific siRNA targets with short hairpin frame were designed and synthesized according to the mRNA sequence of rat CD40 gene. DNA oligo was cloned into lentiviral expression vector, and then PCR and sequencing analyses were conducted to verify the constructs. The verified plasmids were transfected into 293T cells that over-express recombinant CD40 in order to select the most effective siRNA targets. shRNA lentivi-ruses from the selected constructs were propagated and harvested with a virus packaging system, and the virus titers were determined. Western blot and Real-time PCR were performed to determine CD40 expression level in the virus-infected dendritic cells. PCR and sequencing analyses reveal that shRNA plasmids of four targets were successfully constructed. The optimal interfering target was selected, and the virus with a titer of 5×10~7 TU/mL was successfully packaged. CD40 expression in rat DCs was knockdown at both mRNA and protein levels by virus infection. In comparison to that of control groups, CD40 mRNA expression and protein expression were decreased by 60.9% and 61.2%, respectively. We have successfully constructed recombinant lentiviral shRNA expression vector targeting rat CD40 gene that can effectively down-regulate CD40 gene expression at mRNA and protein levels in rat DC.

  12. Identification of MicroRNA Precursors with Support Vector Machine and String Kernel

    Institute of Scientific and Technical Information of China (English)

    Jian-Hua Xu; Fei Li; Qiu-Feng Sun

    2008-01-01

    MicroRNAs (miRNAs) are one family of short (21-23 nt) regulatory non-coding RNAs processed from long (70-110 nt) miRNA precursors (pre-miRNAs). Identifying true and false precursors plays an important role in computational identification of miRNAs. Some numerical features have been extracted from precursor sequences and their secondary structures to suit some classification methods; however, they may lose some usefully discriminative information hidden in sequences and structures. In this study, pre-miRNA sequences and their secondary structures are directly used to construct an exponential kernel based on weighted Levenshtein distance between two sequences. This string kernel is then combined with support vector machine (SVM) for detecting true and false pre-miRNAs. Based on 331 training samples of true and false human pre-miRNAs, 2 key parameters in SVM are selected by 5-fold cross validation and grid search, and 5 realizations with different 5-fold partitions are executed. Among 16 independent test sets from 3 human, 8 animal, 2 plant, 1 virus, and 2 artificially false human pre-miRNAs, our method statistically outperforms the previous SVM-based technique on 11 sets, including 3 human, 7 animal, and 1 false human pre-miRNAs. In particular, premiRNAs with multiple loops that were usually excluded in the previous work are correctly identified in this study with an accuracy of 92.66%.

  13. Prediction of hydrogen and carbon chemical shifts from RNA using database mining and support vector regression

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Joshua D.; Summers, Michael F. [University of Maryland Baltimore County, Howard Hughes Medical Institute (United States); Johnson, Bruce A., E-mail: bruce.johnson@asrc.cuny.edu [University of Maryland Baltimore County, Department of Chemistry and Biochemistry (United States)

    2015-09-15

    The Biological Magnetic Resonance Data Bank (BMRB) contains NMR chemical shift depositions for over 200 RNAs and RNA-containing complexes. We have analyzed the {sup 1}H NMR and {sup 13}C chemical shifts reported for non-exchangeable protons of 187 of these RNAs. Software was developed that downloads BMRB datasets and corresponding PDB structure files, and then generates residue-specific attributes based on the calculated secondary structure. Attributes represent properties present in each sequential stretch of five adjacent residues and include variables such as nucleotide type, base-pair presence and type, and tetraloop types. Attributes and {sup 1}H and {sup 13}C NMR chemical shifts of the central nucleotide are then used as input to train a predictive model using support vector regression. These models can then be used to predict shifts for new sequences. The new software tools, available as stand-alone scripts or integrated into the NMR visualization and analysis program NMRViewJ, should facilitate NMR assignment and/or validation of RNA {sup 1}H and {sup 13}C chemical shifts. In addition, our findings enabled the re-calibration a ring-current shift model using published NMR chemical shifts and high-resolution X-ray structural data as guides.

  14. Hsp90 interacts specifically with viral RNA and differentially regulates replication initiation of Bamboo mosaic virus and associated satellite RNA.

    Directory of Open Access Journals (Sweden)

    Ying Wen Huang

    Full Text Available Host factors play crucial roles in the replication of plus-strand RNA viruses. In this report, a heat shock protein 90 homologue of Nicotiana benthamiana, NbHsp90, was identified in association with partially purified replicase complexes from BaMV-infected tissue, and shown to specifically interact with the 3' untranslated region (3' UTR of BaMV genomic RNA, but not with the 3' UTR of BaMV-associated satellite RNA (satBaMV RNA or that of genomic RNA of other viruses, such as Potato virus X (PVX or Cucumber mosaic virus (CMV. Mutational analyses revealed that the interaction occurs between the middle domain of NbHsp90 and domain E of the BaMV 3' UTR. The knockdown or inhibition of NbHsp90 suppressed BaMV infectivity, but not that of satBaMV RNA, PVX, or CMV in N. benthamiana. Time-course analysis further revealed that the inhibitory effect of 17-AAG is significant only during the immediate early stages of BaMV replication. Moreover, yeast two-hybrid and GST pull-down assays demonstrated the existence of an interaction between NbHsp90 and the BaMV RNA-dependent RNA polymerase. These results reveal a novel role for NbHsp90 in the selective enhancement of BaMV replication, most likely through direct interaction with the 3' UTR of BaMV RNA during the initiation of BaMV RNA replication.

  15. Construction and detection of expression vectors of microRNA-9a in BmN cells

    Institute of Scientific and Technical Information of China (English)

    Yong HUANG; Quan ZOU; Sheng-peng WANG; Shun-ming TANG; Guo-zheng ZHANG; Xing-jia SHEN

    2011-01-01

    MicroRNAs (miRNAs) are small endogenous RNAs molecules,approximately 21-23 nucleotides in length,which regulate gene expression by base-pairing with 3' untranslated regions (UTRs) of target mRNAs.However,the functions of only a few miRNAs in organisms are known.Recently,the expression vector of artificial miRNA has become a promising tool for gene function studies.Here,a method for easy and rapid construction of eukaryotic miRNA expression vector was described.The cytoplasmic actin 3 (A3) promoter and flanked sequences of miRNA-9a (miR-9a)precursor were amplified from genomic DNA of the silkworm (Bombyx mori) and was inserted into pCDNA3.0 vector to construct a recombinant plasmid.The enhanced green fluorescent protein (EGFP) gene was used as reporter gene.The Bombyx mori N (BmN) cells were transfected with recombinant miR-9a expression plasmid and were harvested 48 h post transfection.Total RNAs of BmN cells transfected with recombinant vectors were extracted and the expression of miR-9a was evaluated by reverse transcriptase polymerase chain reaction (RT-PCR) and Northern blot.Tests showed that the recombinant miR-9a vector was successfully constructed and the expression of miR-9a with EGFP was detected.=miRNA-9a (miR-9a),EGFP gene,Bombyx mori N (BmN) Cells,Expression vector

  16. RNA interference-mediated silencing of SOCS-1 via lentiviral vector promotes apoptosis of alveolar epithelial cells in vitro.

    Science.gov (United States)

    Qian, Yan-Rong; Zhang, Qiu-Rui; Cheng, Ting; Wan, Huan-Ying; Zhou, Min

    2012-02-01

    Suppressor of cytokine signaling-1 (SOCS1) is a protein that negatively regulates cytokine and growth factor signaling. However, little is known regarding the precise role it plays in idiopathic pulmonary fibrosis. The aim of the present study was to construct a recombinant lentiviral vector for RNA interference targeting the SOCS1 gene and to detect the expression in human alveolar epithelial cells. A lentiviral vector-mediated RNA interference method was used to establish a SOCS1-negative cell line of alveolar origin (A549). Three pairs of complementary small hairpin RNA (shRNA) oligonucleotides targeting the SOCS1 gene were designed, synthesized and inserted into the pPll3.7 vector. Packaged lentivirus particles were obtained after 48 h, and the supernatant was used to transfect the human alveolar epithelial cell line A549. The expression of the SOCS1 protein was detected by Western blotting. MTT assay was used to detect the cell proliferation of alveolar epithelial cells with SOCS1 knockdown. The recombinant plasmids were confirmed by sequencing. The lentivirus-containing supernatant effectively infected the A549 cell line, and the expression of SOCS1 protein was inhibited, which was confirmed by Western blotting in the target cells. MTT assay indicated the inhibition effect for cell proliferation of A549 cells in the SOCS1-RNA interference group, compared to the control group with no interference-mediated silencing of the SOCS1 gene. A lentiviral vector for RNA interference targeting the SOCS1 gene was successfully constructed, and cell survival tests showed that knockdown of the SOCS1 gene promotes the apoptosis of alveolar cells.

  17. Expression of multiple artificial microRNAs from a chicken miRNA126-based lentiviral vector.

    Directory of Open Access Journals (Sweden)

    Steve C-Y Chen

    Full Text Available BACKGROUND: The use of RNAi in both basic and translational research often requires expression of multiple siRNAs from the same vector. METHODS/PRINCIPAL FINDINGS: We have developed a novel chicken miR126-based artificial miRNA expression system that can express one, two or three miRNAs from a single cassette in a lentiviral vector. We show that each of the miRNAs expressed from the same lentiviral vector is capable of potent inhibition of reporter gene expression in transient transfection and stable integration assays in chicken fibroblast DF-1 cells. Transduction of Vero cells with lentivirus expressing two or three different anti-influenza miRNAs leads to inhibition of influenza virus production. In addition, the chicken miR126-based expression system effectively inhibits reporter gene expression in human, monkey, dog and mouse cells. These results demonstrate that the flanking regions of a single primary miRNA can support processing of three different stem-loops in a single vector. CONCLUSIONS/SIGNIFICANCE: This novel design expands the means to express multiple miRNAs from the same vector for potent and effective silencing of target genes and influenza virus.

  18. The Generation of Eukaryotic Expression Vectors of shRNA Specific for Stat6

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    1 Introduction Since RNA interference (RNAi) was first discovered in plant and the nematode Caenorhabditis elegans in 1998~([1]), it quickly became a powerful and indispensable tool in the molecular toolkit. Small interfering RNA (siRNA) that binds to specific endogenous mRNA and induce their degradation is now widely employed to inhibit protein expression at post-transcriptional level. Recently, RNAi techniques have employed short hairpin RNA (shRNA) instead of siRNA because shRNA can generate siRNA in cel...

  19. Transfection of infectious RNA and DNA/RNA layered vectors of semliki forest virus by the cell-penetrating peptide based reagent PepFect6.

    Directory of Open Access Journals (Sweden)

    Kalle Pärn

    Full Text Available Viral vectors have a wide variety of applications ranging from fundamental studies of viruses to therapeutics. Recombinant viral vectors are usually constructed using methods of reverse genetics to obtain the genetic material of the viral vector. The physicochemical properties of DNA and RNA make them unable to access cells by themselves, and they require assistance to achieve intracellular delivery. Non-viral delivery vectors can be used for this purpose if they enable efficient intracellular delivery without interfering with the viral life cycle. In this report, we utilize Semliki Forest virus (genus alphavirus based RNA and DNA vectors to study the transfection efficiency of the non-viral cell-penetrating peptide-based delivery vector PepFect6 in comparison with that of the cationic liposome-based Lipofectamine 2000, and assess their impact on viral replication. The optimal conditions for transfection were determined for both reagents. These results demonstrate, for the first time, the ability of PepFect6 to transport large (13-19 kbp constructs across the cell membrane. Curiously, DNA molecules delivered using the PepFect6 reagent were found to be transported to the cell nucleus approximately 1.5 hours later than DNA molecules delivered using the Lipofectamine 2000 reagent. Finally, although both PepFect6 and Lipofectamine 2000 reagents can be used for alphavirus research, PepFect6 is preferred because it does not induce changes in the normal cellular phenotype and it does not affect the normal replication-infection cycle of viruses in previously transfected cells.

  20. Characterization and vectorization of siRNA targeting RET/PTC1 in human papillary thyroid carcinoma cells

    Directory of Open Access Journals (Sweden)

    Massade L.

    2011-10-01

    Full Text Available RET/PTC1 fusion oncogene is the most common genetic alteration identified to date in thyroid papillary carcinomas (PTC and represents a good target for small interfering RNA (siRNA. Our aim was: i to target the RET/PTC1 oncogene by siRNAs, ii to assess the knockdown effects on cell growth and cell cycle regulation and iii to vectorize it in order to protect it from degradation. Methods. Human cell lines expressing RET/PTC1 were transfected by siRNA RET/PTC1, inhibition of the oncogene expression was assessed by qRT-PCR and by Western blot. Conjugation of siRNA RET/PTC1 to squalene was performed by coupling it to squalene. In vivo studies are performed in nude mice. Conclusion. In this short communication, we report the main published results obtained during last years.

  1. Design, synthesis and evaluation of VEGF-siRNA/CRS as a novel vector for gene delivery

    Directory of Open Access Journals (Sweden)

    Zhao W

    2016-11-01

    Full Text Available Wen Zhao, Yifan Zhang, Xueyun Jiang, Chunying Cui School of Chemical Biology and Pharmaceutical Sciences, Capital Medical University, Beijing, China Abstract: Small interfering RNA (siRNA delivery is a prospective method in gene therapy, but it has application limitations such as negative charge, water solubility and high molecular weight. In this study, a safe and efficient nano-vector, CRS, was designed and synthesized to facilitate siRNA delivery. Physical and chemical properties of VEGF-siRNA/CRS were characterized by methods including scanning electron microscopy (SEM, transmission electron microscopy, zeta potential (ζ measurement, drug-releasing rate measurement, gel electrophoresis and confocal microscopy. The biological activities were evaluated using cell viability assay, gene-silencing efficacy assay in vitro, real-time polymerase chain reaction, enzyme-linked immunosorbent assay (ELISA and antitumor tests in vivo. The mean nanoparticle size of VEGF-siRNA/CRS was 121.4±0.3 nm with positive ζ potential of 7.69±4.47 mV. The release rate of VEGF-siRNA from VEGF-siRNA/CRS was 82.50% sustained for 48 h in Tris-ethylenediaminetetraacetic acid buffer (pH 8.0. Real-time polymerase chain reaction was used to analyze the efficiency of the transfection, and the result showed that VEGF mRNA expression had been knocked down by 82.36%. The expression of VEGF protein was also recorded to be downregulated to 14.83% using ELISA. The results of cytotoxicity measured by Cell Counting Kit-8 assay showed that VEGF-siRNA/CRS had significant inhibitory effect on HeLa cells. The results of antitumor assays indicated that VEGF-siRNA/CRS exhibited tumor cell growth inhibition in vivo. The results demonstrated that VEGF-siRNA could be delivered and transported by the designed carrier, while siRNA could be released constantly and led to an increasing gene-silencing effect against VEGF gene. In conclusion, VEGF-siRNA/CRS is a promising carrier for siRNA

  2. Lentiviral vector-mediated siRNA knockdown of SR-PSOX inhibits foam cell formation in vitro

    Institute of Scientific and Technical Information of China (English)

    Li ZHANG; Hou-jia LIU; Tie-jun LI; Yang YANG; Xian-ling GUO; Meng-chao WU; Yao-cheng RUI; Li-xin WEI

    2008-01-01

    Aim: To investigate the expression of scavenger receptor that binds phosphatidylserine and oxidized lipoprotein (SR-PSOX)/CXC chemokine ligand 16 (CXCL16) in the human monocyte-derived cell line THP-1, and the effect of lentiviral vectors for the stable delivery of SR-PSOX/CXCL16 short hairpin RNA on foam cell formation. Methods: A lentiviral expression vector containing enhanced green fluorescence protein (GFP) and SR-PSOX small interfering RNA (siRNA) (Lenti-SR-PSOXsi), or the control siRNA (Lenti-NC) gene was constructed. A human monocyte-derived cell line THP-1 was transfected with a different multiplicity of infection (MOI) of Lenti-SR-PSOXsi or Lenti-NC, and cultured to obtain stably-transfected THP-1KD and THP-1NC cells. After incubation with oxidatively-modified, low-density lipoprotein (Ox-LDL), the expression of SR-PSOX/CXCL16 mRNA was determined by real-time PCR. The expression of the SR-PSOX/CXCL16 protein was detected by flow cytometry analysis. The effect of Lenti-SR-PSOXsi on foam cell formation was assessed by Oil red O-stain analysis. Results: Ox-LDL increased the expres-sion of SR-PSOX/CXCL 16 mRNA in a time- and dose-dependent manner in THP-1 cells. Four days after transfection with Lenti-SR-PSOXsi (MOI: 100), the percent-age of GFP expression cells was over 89.3%. The expression of the SR-PSOX/ CXCL 16 mRNA and protein in THP- 1KD cells significantly decreased compared with the parent cells, even the THP-1KD cells stimulated with 40 mg/L Ox-LDL. Ox-LDL uptake experiments in THP-1- and THP- 1KD-derived macrophages indi-cated that SR-PSOX/CXCL16 deficiency decreased the development of macroph-age-derived foam cell formation. Conclusion: The above data showed that SR-PSOX siRNA delivered by using lentiviral vectors in THP-1 cells was a powerful tool for studying the effect of SR-PSOX, and decreased the expression of the SR-PSOX gene by inhibiting macrophage-derived foam cell formation.

  3. Transfer of primer binding site-mutated simian immunodeficiency virus vectors by genetically engineered artificial and hybrid tRNA-like primers

    DEFF Research Database (Denmark)

    Hansen, A C; Grunwald, T; Lund, Anders Henrik

    2001-01-01

    could be obtained by cotransfection of a gene for an engineered tRNA(Pro)-tRNA hybrid with a match to PBS-Pro. The importance of tRNA backbone identity was further analyzed by complementing the PBS-X2 vector with a gene for a matching x2 primer with a tRNA backbone, which led to three- to fourfold...

  4. Hybrid cytomegalovirus-U6 promoter-based plasmid vectors improve efficiency of RNA interference in zebrafish.

    Science.gov (United States)

    Su, Jianguo; Zhu, Zuoyan; Xiong, Feng; Wang, Yaping

    2008-01-01

    Short hairpin RNA (shRNA) directed by RNA polymerase III (Pol III) or Pol II promoter was shown to be capable of silencing gene expression, which should permit analyses of gene functions or as a potential therapeutic tool. However, the inhibitory effect of shRNA remains problematic in fish. We demonstrated that silencing efficiency by shRNA produced from the hybrid construct composed of the CMV enhancer or entire CMV promoter placed immediately upstream of a U6 promoter. When tested the exogenous gene, silencing of an enhanced green fluorescent protein (EGFP) target gene was 89.18 +/- 5.06% for CMVE-U6 promoter group and 88.26 +/- 6.46% for CMV-U6 promoter group. To test the hybrid promoters driving shRNA efficiency against an endogenous gene, we used shRNA against no tail (NTL) gene. When vectorized in the zebrafish, the hybrid constructs strongly repressed NTL gene expression. The NTL phenotype occupied 52.09 +/- 3.06% and 51.56 +/- 3.68% for CMVE-U6 promoter and CMV-U6 promoter groups, respectively. The NTL gene expression reduced 82.17 +/- 2.96% for CMVE-U6 promoter group and 83.06 +/- 2.38% for CMV-U6 promoter group. We concluded that the CMV enhancer or entire CMV promoter locating upstream of the U6-promoter could significantly improve inhibitory effect induced by the shRNA for both exogenous and endogenous genes compared with the CMV promoter or U6 promoter alone. In contrast, the two hybrid promoter constructs had similar effects on driving shRNA.

  5. Reversal of Multi-Drug Resistance by Vector-Based-ShRNA-Mdr1 In Vitro and In Vivo

    Institute of Scientific and Technical Information of China (English)

    Shi LU; Qi HUANG; Zehua WANG; Yinfeng SONG; Lijun WANG

    2009-01-01

    In order to investigate the effects of vector-based hairpin small interference RNA (shRNA) on the reversal of multi-drug resistance (mdr) of A2780/Taxol cells, a novel vector pEGFP-H1/mdr1 containing mdr1-shRNA targeting at position 2943-2963 of mdr1 was designed and synthesized.Subsequently, A2780/Taxol cells were transfected with pEGFP-H1/mdrl, and the expression of mdr1 mRNA and P-gp was detected by using RT-PCR and Western blot respectively. MTT was used to measure the 50% inhibition concentration (1C50) of Taxol to A2780/Taxol cells. The results showed that at the 24th and 48th h after transfection, the expression of mdr1 mRNA was decreased to (52.1±1.0)% and (0.01+1.7)%, and that of P-gp decreased to (88.3±2.1)% and 0%, respectively. At the 48th h after transfection, the relative reversal rate of A2780/Taxol cells to Taxol was 69.54%. In vivo, the nude mice xenografts were injected with pEGFP-H1/mdrl, and then administrated Taxol.The tumor volume in pEGFP-H1/mdr1-transfected group was significantly reduced as compared with that in blank control group or pEGFP-H1-transfected group (807.20±103.16 vs 1563.78±210.54 or 1480.78±241.24 mm3, both P<0.01). These results suggested that transfection of pEGFP-H1/mdr1 could efficiently down-regulate the expression of mdr1 mRNA and P-gp in A2780/Taxol cells, and effectively restore the sensitivity of A2780/Taxol cells to Taxol both in vitro and in vivo.

  6. Construction and identification of an RNA interference lentivirus vector targeting the Ras homology C gene of melanoma cells

    Institute of Scientific and Technical Information of China (English)

    Wang Qiying; Wang Ximei; Zhai Xiaomei; Zhang Jianwen; Chen Minjing; Liu Linbo

    2014-01-01

    Background Melanoma has the highest mortality among all superficial malignant tumors.The poor prognosis is due to its high metastasis rate and the lack of therapeutic targets.As a molecular switch that controls tumor metastasis,Ras homology C (RhoC) has been correlated with tumor progression,especially tumor invasion and metastasis.However,little research has been done about the effects of RNA interference (RNAi) targeting RhoC on the invasion and metastasis of melanoma.In this study,we constructed an RNAi lentivirus vector targeting the RhoC gene of melanoma cells and identified its silencing effects on the RhoC gene.Methods Based on the RhoC gene encoding information,three pGPU6/GFP/Neo-short hairpin (shRNA) plasmids were constructed.After detecting their silencing effects on the RhoC gene of A375 cells,the most effective pGPU6/GFP/ Neo-shRNA plasmid was packed with lentivirus to construct the recombinant pLenti6.3-EGFP-453 targeting RhoC.The lentivirus vector was used to infect A375 cells,and then the expression of RhoC mRNA and protein were determined with real-time PCR and Western blotting.Results The plasmids pGPU6/GFP/Neo-shRNA 336,pGPU6/GFP/Neo-shRNA 453,and pGPU6/GFP/Neo-shRNA 680 were constructed.After they were transfected into A375 cells,the expressions of RhoC mRNA and protein were 1.47±0.26,1.13±0.16,1.39±0.11 and 70.98±9.21,50.67±6.06,65.77±4.06,respectively.pGPU6/GFP/Neo-shRNA 453 was the most effective sequence,and was used to successfully construct the pLenti6.3-EGFP-453 lentiviral vector targeting RhoC.pLenti6.3-EGFP-453 was used to infect A375 cells.The expression of RhoC mRNA and protein were 1.05±0.05 and 62.04±15.86 in the lentivirus group,4.21±0.24 and 220.86±24.07 in the negative lentivirus control group,and 4.63±0.32 and 257.39±12.30 in the normal control group respectively with the difference between the lentivirus group and the control groups being statistically significant (P <0.05).Conclusion The successfully constructed

  7. microRNA as a potential vector for the propagation of robustness in protein expression and oscillatory dynamics within a ceRNA network.

    Directory of Open Access Journals (Sweden)

    Claude Gérard

    Full Text Available microRNAs (miRNAs are small noncoding RNAs that are important post-transcriptional regulators of gene expression. miRNAs can induce thresholds in protein synthesis. Such thresholds in protein output can be also achieved by oligomerization of transcription factors (TF for the control of gene expression. First, we propose a minimal model for protein expression regulated by miRNA and by oligomerization of TF. We show that miRNA and oligomerization of TF generate a buffer, which increases the robustness of protein output towards molecular noise as well as towards random variation of kinetics parameters. Next, we extend the model by considering that the same miRNA can bind to multiple messenger RNAs, which accounts for the dynamics of a minimal competing endogenous RNAs (ceRNAs network. The model shows that, through common miRNA regulation, TF can control the expression of all proteins formed by the ceRNA network, even if it drives the expression of only one gene in the network. The model further suggests that the threshold in protein synthesis mediated by the oligomerization of TF can be propagated to the other genes, which can increase the robustness of the expression of all genes in such ceRNA network. Furthermore, we show that a miRNA could increase the time delay of a "Goodwin-like" oscillator model, which may favor the occurrence of oscillations of large amplitude. This result predicts important roles of miRNAs in the control of the molecular mechanisms leading to the emergence of biological rhythms. Moreover, a model for the latter oscillator embedded in a ceRNA network indicates that the oscillatory behavior can be propagated, via the shared miRNA, to all proteins formed by such ceRNA network. Thus, by means of computational models, we show that miRNAs could act as vectors allowing the propagation of robustness in protein synthesis as well as oscillatory behaviors within ceRNA networks.

  8. An MRI-visible non-viral vector for targeted Bcl-2 siRNA delivery to neuroblastoma

    Directory of Open Access Journals (Sweden)

    Shen M

    2012-07-01

    Full Text Available Min Shen,1,* Faming Gong,3,* Pengfei Pang,1,* Kangshun Zhu,1 Xiaochun Meng,1 Chun Wu,1 Jin Wang,1 Hong Shan,1,2 Xintao Shuai3,41Molecular Imaging Lab, Department of Radiology, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, China; 2Institute of Intervention Radiology, Sun Yat-sen University, Guangzhou, China; 3PCFM Lab of Ministry of Education, School of Chemistry and Chemical Engineering, Sun Yat-sen University, Guangzhou, China; 4Center of Biomedical Engineering, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, China*These authors contributed equally to this workAbstract: Polyethylene glycol-grafted polyethylenimine (PEG-g-PEI which was functionalized with a neuroblastoma cell-specific ligand, the GD2 single chain antibody (scAbGD2, was synthesized in order to effectively deliver Bcl-2 siRNA into neuroblastoma cells. This polymer was complexed first with superparamagnetic iron oxide nanoparticle (SPION to get a MRI-visible targeted non-viral vector (scAbGD2-PEG-g-PEI-SPION and then with Bcl-2 siRNA to form nanoparticles showing low cytotoxicity. The targeting capacity of scAbGD2-PEG-g-PEI-SPION was successfully verified in vivo and in vitro by magnetic resonance imaging. The single chain antibody encoded targeted polyplex was more effective in transferring Bcl-2 siRNA than the nontargeting one in SK-N-SH cells, a human neuroblastoma cell line, resulting in a 46.34% inhibition in the expression of Bcl-2 mRNA. Consequently, a high level of cell apoptosis up to 50.76% and a significant suppression of tumor growth were achieved, which indicates that scAbGD2-PEG-g-PEI-SPION is a promising magnetic resonance imaging-visible non-viral vector for targeted neuroblastoma siRNA therapy and diagnosis.Keywords: tumor targeting, GD2, non-viral vector, Bcl-2 small interfering RNA, magnetic resonance imaging

  9. Photoluminescent and biodegradable polycitrate-polyethylene glycol-polyethyleneimine polymers as highly biocompatible and efficient vectors for bioimaging-guided siRNA and miRNA delivery.

    Science.gov (United States)

    Wang, Min; Guo, Yi; Yu, Meng; Ma, Peter X; Mao, Cong; Lei, Bo

    2017-02-20

    Development of biodegradable and biocompatible non-viral vectors with intrinsical multifunctional properties such as bioimaging ability for highly efficient nucleic acids delivery still remains a challenge. Here, a biodegradable poly (1,8-octanedio-citric acid)-co-polyethylene glycol grafted with polyethyleneimine (PEI) (POCG-PEI) polymers with the photoluminescent capacity were synthesized for nucleic acids delivery (siRNA and miRNA). POCG-PEI polymers can efficiently bind various nucleic acids, protect them against enzymatic degradation and release the genes in the presence of polyanionic heparin. POCG-PEI also showed a significantly low cytotoxicity, enhanced cellular uptake and high transfection efficiency of nucleic acids, as compared to commercial transfection agents, lipofectamine 2000 (Lipo) and polyethylenimine (PEI 25K). POCG-PEI polymers demonstrate an excellent photostability, which allows for imaging the cells and real-time tracking the nucleic acids delivery. The photoluminescent property, low cytotoxicity, biodegradation, good gene binding and protection ability and high genes delivery efficiency make POCG-PEI highly competitive as a non-virus vector for genes delivery and real-time bioimaging applications. Our results may be also an important step for designing biodegradable biomaterials with multifunctional properties towards bioimaging-guided genes therapeutic applications.

  10. A facile lentiviral vector system for expression of doxycycline-inducible shRNAs: knockdown of the pre-miRNA processing enzyme Drosha

    DEFF Research Database (Denmark)

    Aagaard, Lars; Amarzguioui, Mohammed; Sun, Guihua

    2007-01-01

    RNA interference (RNAi) is a powerful genetic tool for loss-of-function studies in mammalian cells and is also considered a potentially powerful therapeutic modality for the treatment of a variety of human diseases. During the past 3 years a number of systems for conditional RNAi have been develo...... Drosha. Drosha is the core catalytic component of the "microprocessor complex" and cleaves the primary microRNA (miRNA) transcripts into their pre-miRNA hairpin intermediates. We anticipate that our vector will facilitate functional studies of miRNA biogenesis....

  11. [MicroRNA Target Prediction Based on Support Vector Machine Ensemble Classification Algorithm of Under-sampling Technique].

    Science.gov (United States)

    Chen, Zhiru; Hong, Wenxue

    2016-02-01

    Considering the low accuracy of prediction in the positive samples and poor overall classification effects caused by unbalanced sample data of MicroRNA (miRNA) target, we proposes a support vector machine (SVM)-integration of under-sampling and weight (IUSM) algorithm in this paper, an under-sampling based on the ensemble learning algorithm. The algorithm adopts SVM as learning algorithm and AdaBoost as integration framework, and embeds clustering-based under-sampling into the iterative process, aiming at reducing the degree of unbalanced distribution of positive and negative samples. Meanwhile, in the process of adaptive weight adjustment of the samples, the SVM-IUSM algorithm eliminates the abnormal ones in negative samples with robust sample weights smoothing mechanism so as to avoid over-learning. Finally, the prediction of miRNA target integrated classifier is achieved with the combination of multiple weak classifiers through the voting mechanism. The experiment revealed that the SVM-IUSW, compared with other algorithms on unbalanced dataset collection, could not only improve the accuracy of positive targets and the overall effect of classification, but also enhance the generalization ability of miRNA target classifier.

  12. Construction and Identification of a Vector Expressing RNA Interference Aimed at the Human CyclinD1 Gene and its Expression in Vitro

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    OBJECTIVE To construct a eukaryotic expression vector for RNA interference of the human cyclinD1 gene, and to detect its interference effect in human ovarian cancer cells (HO-8910).METHODS Four target gene segments were synthesized and cloned into the pSUPER vector respectively to construct four recombinant eukaryotic expression vectors, pSUPER-C1~4. The four recombinant vectors were identified by enzyme digestion analysis and DNA sequencing. Then HO-8910 cells were transfected with the pSUPER-C1~4 vectors and subjected to G418 selection. In G418-resistant cells, the interference effect was detected by RT-PCR.RESULTS Enzyme digestion analysis and DNA sequencing showed that the target segments were cloned into the pSUPER vector. The four recombinant vectors inhibited transcription of the cyclinD1 gene. The pSUPER-C2 vector had a better interference effect.CONCLUSION The sequence-specific siRNA effectively interfered with expression of the cyclinD1 gene that was selected. The transcription and expression of the cyclinD1 gene were inhibited effectively by the constructed RNAi eukaryotic expression vectors in the ovarian cancer cells. These results indicate that it is possible to search for a new tumor gene therapy method.

  13. Construction and Expression of Eukaryotic Expression Vector and Plasmid Expressing siRNA of Human Protection of Telomeres 1

    Institute of Scientific and Technical Information of China (English)

    Di-Nan HUANG; Ying-Hua JIANG; Hou GAN

    2005-01-01

    @@ 1 Introduction The POT1 (protection of telomeres 1 ) protein binds the single-stranded overhang at the ends of chromosomes in diverse eukaryocytes. It is essential for chromosome end-protection in the fission yeast Schizosaccharomyces pombe, and it is involved in regulation of telomere lengthin human cells. Human POT1 had been identified in 2001year. Its amino terminal is highly conservative in eukaryocytes. Since Pot1 can bind internal loops and directly adjacent DNA-binding sites, it is likely to fully coat and protect both G-strand overhangs and the displaced G strand of a T-loop. It also participates in the regulation of telomere maintenance by telomerase or of chromosome by other enzymes. But its biological function and mechanism are still unknown. hPOT eukaryotic expression vector(pcDNA3- hPOT1 ) and 3 kinds of siRNA expression vectors(pmU6-shDNA1, pmU6-shDNA2 and pmU6-shDNA3)had been constructed. And there were overexpression and RNA silence in HeLa cells.

  14. Development of a novel adenovirus-alphavirus hybrid vector with RNA replicon features for malignant hematopoietic cell transduction.

    Science.gov (United States)

    Yang, Y; Xiao, F; Lu, Z; Li, Z; Zuo, H; Zhang, Q; Li, Q; Wang, H; Wang, L-S

    2013-08-01

    To improve the expression levels of transgenes in malignant hematopoietic cells, we developed a novel adenoviral-alphavirus hybrid vector Ad5/F11p-SFV-GFP that contains a Semliki Forest Virus (SFV) replicon and chimeric fibers of Ad5 and Ad11p. Ad5/F11p-SFV-GFP infected >95% of K562, U937 or Jurkat cells and 23.65% of HL-60 cells, and led to moderate Enhanced Green Fluorescent Protein (EGFP) transgene expression intensity. The infection efficiency of Ad5/F11p-SFV-GFP in primary human leukemia cells ranged from 9.34-89.63% (median, 28.58%) at a multiplicity of infection (MOI) of 100, compared with only 3.37-44.54% (median, 10.42%) in cells infected by Ad5/F11p-GFP. Importantly, Ad5/F11p-SFV-GFP led to a significantly higher transgene expression level in primary leukemia cells, as indicated by the relative fluorescence intensity, compared to cells infected with Ad5/F11p-GFP. The increased expression of EGFP in Ad5/F11p-SFV-GFP-infected cells was associated with the accumulation of abundant subgenomic mRNA. Additionally, infection of K562, U937 or Jurkat cells by Ad5/F11p-SFV-GFP was significantly inhibited by blocking CD46 receptor; however, other factors may affect the gene-transfer efficiency of Ad5/F11p-SFV-GFP in primary leukemia cells. In conclusion, we successfully developed a novel adenoviral-alphavirus hybrid vector with RNA replicon features, which represents a promising vector for gene modifications during the production of cell-based vaccines for leukemia patients.

  15. siRNA-Mediated Silencing of doublesex during Female Development of the Dengue Vector Mosquito Aedes aegypti.

    Science.gov (United States)

    Mysore, Keshava; Sun, Longhua; Tomchaney, Michael; Sullivan, Gwyneth; Adams, Haley; Piscoya, Andres S; Severson, David W; Syed, Zainulabeuddin; Duman-Scheel, Molly

    2015-11-01

    The development of sex-specific traits, including the female-specific ability to bite humans and vector disease, is critical for vector mosquito reproduction and pathogen transmission. Doublesex (Dsx), a terminal transcription factor in the sex determination pathway, is known to regulate sex-specific gene expression during development of the dengue fever vector mosquito Aedes aegypti. Here, the effects of developmental siRNA-mediated dsx silencing were assessed in adult females. Targeting of dsx during A. aegypti development resulted in decreased female wing size, a correlate for body size, which is typically larger in females. siRNA-mediated targeting of dsx also resulted in decreased length of the adult female proboscis. Although dsx silencing did not impact female membrane blood feeding or mating behavior in the laboratory, decreased fecundity and fertility correlated with decreased ovary length, ovariole length, and ovariole number in dsx knockdown females. Dsx silencing also resulted in disruption of olfactory system development, as evidenced by reduced length of the female antenna and maxillary palp and the sensilla present on these structures, as well as disrupted odorant receptor expression. Female lifespan, a critical component of the ability of A. aegypti to transmit pathogens, was also significantly reduced in adult females following developmental targeting of dsx. The results of this investigation demonstrate that silencing of dsx during A. aegypti development disrupts multiple sex-specific morphological, physiological, and behavioral traits of adult females, a number of which are directly or indirectly linked to mosquito reproduction and pathogen transmission. Moreover, the olfactory phenotypes observed connect Dsx to development of the olfactory system, suggesting that A. aegypti will be an excellent system in which to further assess the developmental genetics of sex-specific chemosensation.

  16. siRNA-Mediated Silencing of doublesex during Female Development of the Dengue Vector Mosquito Aedes aegypti.

    Directory of Open Access Journals (Sweden)

    Keshava Mysore

    2015-11-01

    Full Text Available The development of sex-specific traits, including the female-specific ability to bite humans and vector disease, is critical for vector mosquito reproduction and pathogen transmission. Doublesex (Dsx, a terminal transcription factor in the sex determination pathway, is known to regulate sex-specific gene expression during development of the dengue fever vector mosquito Aedes aegypti. Here, the effects of developmental siRNA-mediated dsx silencing were assessed in adult females. Targeting of dsx during A. aegypti development resulted in decreased female wing size, a correlate for body size, which is typically larger in females. siRNA-mediated targeting of dsx also resulted in decreased length of the adult female proboscis. Although dsx silencing did not impact female membrane blood feeding or mating behavior in the laboratory, decreased fecundity and fertility correlated with decreased ovary length, ovariole length, and ovariole number in dsx knockdown females. Dsx silencing also resulted in disruption of olfactory system development, as evidenced by reduced length of the female antenna and maxillary palp and the sensilla present on these structures, as well as disrupted odorant receptor expression. Female lifespan, a critical component of the ability of A. aegypti to transmit pathogens, was also significantly reduced in adult females following developmental targeting of dsx. The results of this investigation demonstrate that silencing of dsx during A. aegypti development disrupts multiple sex-specific morphological, physiological, and behavioral traits of adult females, a number of which are directly or indirectly linked to mosquito reproduction and pathogen transmission. Moreover, the olfactory phenotypes observed connect Dsx to development of the olfactory system, suggesting that A. aegypti will be an excellent system in which to further assess the developmental genetics of sex-specific chemosensation.

  17. The Comparative and Functional Study between Two Construction Methods of shRNA Expression Vector Targeted LMP1 Gene Encoded by EBV

    Institute of Scientific and Technical Information of China (English)

    Yi-qin WANG; Yu-cheng YANG; Wen-lu ZHANG; Su-ling HONG

    2007-01-01

    To look for a more stable and convenient way of constructing short hairpin RNA expression vectors targeting the latent membrane protein-1(LMP-1) encoded by Epstein-Barr virus(pshLMP1), and to study the inhibition function of pshLMP1 expression vectors in HNE1 cells, we designed the pshLMP1 expression cassette and pshLMP1 expression vectors by both the annealing method and PCR method and then co-transfected with pEGFP-N1-1158 into HNE1 cells to observe the mRNA and protein levels of LMP-1 genes by green fluorescence analysis, RT-PCR and western blot. pshLMP1 expression vectors were successfully obtained by both methods but better cloning efficiency was achieved and fewer deletions and mutations of nucleotides were achieved with the PCR method. Furthermore, the mRNA and protein levels of LMP-1 genes were down-regulated by pshLMP1 expression vectors. According to our research, we found that the PCR method provides a more efficient way to construct pshLMP1 expression vectors which have the ability to inhibit the function of LMP-1 genes expressed in HNE1 cells, and also provides a novel application of RNA interference technology against-EBV.

  18. RNA viral vectors for improved Agrobacterium-mediated transient expression of heterologous proteins in Nicotiana benthamiana cell suspensions and hairy roots

    Directory of Open Access Journals (Sweden)

    Larsen Jeffrey S

    2012-05-01

    Full Text Available Abstract Background Plant cell suspensions and hairy root cultures represent scalable protein expression platforms. Low protein product titers have thus far limited the application of transient protein expression in these hosts. The objective of this work was to overcome this limitation by harnessing A. tumefaciens to deliver replicating and non-replicating RNA viral vectors in plant tissue co-cultures. Results Replicating vectors derived from Potato virus X (PVX and Tobacco rattle virus (TRV were modified to contain the reporter gene β-glucuronidase (GUS with a plant intron to prevent bacterial expression. In cell suspensions, a minimal PVX vector retaining only the viral RNA polymerase gene yielded 6.6-fold more GUS than an analogous full-length PVX vector. Transient co-expression of the minimal PVX vector with P19 of Tomato bushy stunt virus or HC-Pro of Tobacco etch virus to suppress post-transcriptional gene silencing increased GUS expression by 44 and 83%, respectively. A non-replicating vector containing a leader sequence from Cowpea mosaic virus (CPMV-HT modified for enhanced translation led to 70% higher transient GUS expression than a control treatment. In hairy roots, a TRV vector capable of systemic movement increased GUS accumulation by 150-fold relative to the analogous PVX vector. Histochemical staining for GUS in TRV-infected hairy roots revealed the capacity for achieving even higher productivity per unit biomass. Conclusions For the first time, replicating PVX vectors and a non-replicating CPMV-HT vector were successfully applied toward transient heterologous protein expression in cell suspensions. A replicating TRV vector achieved transient GUS expression levels in hairy roots more than an order of magnitude higher than the highest level previously reported with a viral vector delivered by A. tumefaciens.

  19. RNA viral vectors for improved Agrobacterium-mediated transient expression of heterologous proteins in Nicotiana benthamiana cell suspensions and hairy roots

    Science.gov (United States)

    2012-01-01

    Background Plant cell suspensions and hairy root cultures represent scalable protein expression platforms. Low protein product titers have thus far limited the application of transient protein expression in these hosts. The objective of this work was to overcome this limitation by harnessing A. tumefaciens to deliver replicating and non-replicating RNA viral vectors in plant tissue co-cultures. Results Replicating vectors derived from Potato virus X (PVX) and Tobacco rattle virus (TRV) were modified to contain the reporter gene β-glucuronidase (GUS) with a plant intron to prevent bacterial expression. In cell suspensions, a minimal PVX vector retaining only the viral RNA polymerase gene yielded 6.6-fold more GUS than an analogous full-length PVX vector. Transient co-expression of the minimal PVX vector with P19 of Tomato bushy stunt virus or HC-Pro of Tobacco etch virus to suppress post-transcriptional gene silencing increased GUS expression by 44 and 83%, respectively. A non-replicating vector containing a leader sequence from Cowpea mosaic virus (CPMV-HT) modified for enhanced translation led to 70% higher transient GUS expression than a control treatment. In hairy roots, a TRV vector capable of systemic movement increased GUS accumulation by 150-fold relative to the analogous PVX vector. Histochemical staining for GUS in TRV-infected hairy roots revealed the capacity for achieving even higher productivity per unit biomass. Conclusions For the first time, replicating PVX vectors and a non-replicating CPMV-HT vector were successfully applied toward transient heterologous protein expression in cell suspensions. A replicating TRV vector achieved transient GUS expression levels in hairy roots more than an order of magnitude higher than the highest level previously reported with a viral vector delivered by A. tumefaciens. PMID:22559055

  20. Improving model predictions for RNA interference activities that use support vector machine regression by combining and filtering features

    Directory of Open Access Journals (Sweden)

    Peek Andrew S

    2007-06-01

    Full Text Available Abstract Background RNA interference (RNAi is a naturally occurring phenomenon that results in the suppression of a target RNA sequence utilizing a variety of possible methods and pathways. To dissect the factors that result in effective siRNA sequences a regression kernel Support Vector Machine (SVM approach was used to quantitatively model RNA interference activities. Results Eight overall feature mapping methods were compared in their abilities to build SVM regression models that predict published siRNA activities. The primary factors in predictive SVM models are position specific nucleotide compositions. The secondary factors are position independent sequence motifs (N-grams and guide strand to passenger strand sequence thermodynamics. Finally, the factors that are least contributory but are still predictive of efficacy are measures of intramolecular guide strand secondary structure and target strand secondary structure. Of these, the site of the 5' most base of the guide strand is the most informative. Conclusion The capacity of specific feature mapping methods and their ability to build predictive models of RNAi activity suggests a relative biological importance of these features. Some feature mapping methods are more informative in building predictive models and overall t-test filtering provides a method to remove some noisy features or make comparisons among datasets. Together, these features can yield predictive SVM regression models with increased predictive accuracy between predicted and observed activities both within datasets by cross validation, and between independently collected RNAi activity datasets. Feature filtering to remove features should be approached carefully in that it is possible to reduce feature set size without substantially reducing predictive models, but the features retained in the candidate models become increasingly distinct. Software to perform feature prediction and SVM training and testing on nucleic acid

  1. Inhibition of avian tumor viruses by vector-based RNA interference

    Science.gov (United States)

    RNA interference (RNAi) has been shown to reduce the replication of certain animal viruses both in cell culture and in live animals. We developed RNAi-based anti-viral strategies against two important chicken pathogens: avian leukosis virus (ALV) and Marek’s Disease virus MDV). Entry plasmids conta...

  2. Suppression of leaky expression of adenovirus genes by insertion of microRNA-targeted sequences in the replication-incompetent adenovirus vector genome

    Directory of Open Access Journals (Sweden)

    Kahori Shimizu

    2014-01-01

    Full Text Available Leaky expression of adenovirus (Ad genes occurs following transduction with a conventional replication-incompetent Ad vector, leading to an induction of cellular immunity against Ad proteins and Ad protein-induced toxicity, especially in the late phase following administration. To suppress the leaky expression of Ad genes, we developed novel Ad vectors by incorporating four tandem copies of sequences with perfect complementarity to miR-122a or miR-142-3p into the 3′-untranslated region (UTR of the E2A, E4, or pIX gene, which were mainly expressed from the Ad vector genome after transduction. These Ad vectors easily grew to high titers comparable to those of a conventional Ad vector in conventional 293 cells. The leaky expression of these Ad genes in mouse organs was significantly suppressed by 2- to 100-fold, compared with a conventional Ad vector, by insertion of the miRNA-targeted sequences. Notably, the Ad vector carrying the miR-122a–targeted sequences into the 3′-UTR of the E4 gene expressed higher and longer-term transgene expression and more than 20-fold lower levels of all the Ad early and late genes examined in the liver than a conventional Ad vector. miR-122a–mediated suppression of the E4 gene expression in the liver significantly reduced the hepatotoxicity which an Ad vector causes via both adaptive and non-adaptive immune responses.

  3. [Construction and identification of a lentiviral vector for RNA interference of human GLUT3 gene].

    Science.gov (United States)

    Zheng, Chuanyi; Chen, Zhenggang; Bai, Enqi; Li, Zhengzheng; Yang, Kun

    2016-05-01

    目的:筛选出人GLUT3基因有效的RNA干扰(RNA interference,RNAi)序列,并构建出慢病毒RNAi载体。方法:根据GLUT3基因mRNA序列设计合成siRNA片段4个,分别定向克隆至pLV-shRNA载体上,并将构建的质粒转染HeLa细胞,运用实时荧光定量PCR(quantitative real-time PCR,qRT-PCR)检测GLUT3mRNA的表达量验证其干扰效果。筛选出其中有效的质粒与病毒包装质粒共转染293T细胞进行包装,收获并浓缩重组慢病毒颗粒,测定病毒颗粒滴度后,将病毒感染U251胶质瘤细胞以测定感染慢病毒干扰载体后胶质瘤细胞内GLUT3的表达情况。结果:重组RNAi质粒pLV-shRNA-GLUT3-1,pLV-shRNA-GLUT3-2,pLV-shRNA-GLUT3-3,pLV-shRNA- GLUT3-4经测序证实质粒载体构建成功;4个干扰质粒在HeLa细胞中均可以明显抑制GLUT3-mRNA的表达。pLV-shRNA-GLUT3可以在293T细胞中成功包装。收集293T细胞分泌的病毒上清浓缩后测定病毒颗粒LV-GLUT3滴度为1.5×109 TU/mL。与感染阴性对照慢病毒颗粒(0.3641±0.044)相比,胶质瘤U251细胞感染慢病毒颗粒LV- GLUT3后,GLUT3蛋白相对表达明显降低(0.108±0.016,t=16.267,P<0.001)。结论:成功构建了人GLUT3基因有效的慢病毒RNAi载体,为进一步研究GLUT3的生物学功能奠定了基础。.

  4. Down-regulation of STAT3 expression by vector-based small interfering RNA inhibits pancreatic cancer growth

    Institute of Scientific and Technical Information of China (English)

    Chen Huang; Guang Yang; Tao Jiang; Jun Cao; Ke-Jian Huang; Zheng-Jun Qiu

    2011-01-01

    AIM: To evaluate the effect of RNA interference (RNAi) mediated silence of signal transduction and activation of transcription (STAT)3 on the growth of human pancreatic cancer cells both in vitro and in vivo . METHODS: STAT3 specific shRNA was used to silence the expression of STAT3 in pancreatic cancer cell line SW1990. The anti-growth effects of RNAi against STAT3 were studied in vitro and in experimental cancer xenografts in nude mice. The potential pathways involved in STAT3 signaling were detected using reverse transcription polymerase chain reaction and western blotting. RESULTS: The expression of the STAT3 was inhibited using RNAi in SW1990 cells. RNAi against STAT3 inhibited cell proliferation, induced cell apoptosis and significantly reduced the levels of CyclinD1 and Bcl-xL when compared with parental and control vector-transfected cells. In vivo experiments showed that RNAi against STAT3 inhibited the tumorigenicity of SW1990 cells and significantly suppressed tumor growth when it was directly injected into tumors. CONCLUSION: STAT3 signaling pathway plays an important role in the progression of pancreatic cancer, and silence of STAT3 gene using RNAi technique may be a novel therapeutic option for treatment of pancreatic cancer.

  5. Mal de Río Cuarto Virus Infection Triggers the Production of Distinctive Viral-Derived siRNA Profiles in Wheat and Its Planthopper Vector

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    Luis A. de Haro

    2017-05-01

    Full Text Available Plant reoviruses are able to multiply in gramineae plants and delphacid vectors encountering different defense strategies with unique features. This study aims to comparatively assess alterations of small RNA (sRNA populations in both hosts upon virus infection. For this purpose, we characterized the sRNA profiles of wheat and planthopper vectors infected by Mal de Río Cuarto virus (MRCV, Fijivirus, Reoviridae and quantified virus genome segments by quantitative reverse transcription PCR We provide evidence that plant and insect silencing machineries differentially recognize the viral genome, thus giving rise to distinct profiles of virus-derived small interfering RNAs (vsiRNAs. In plants, most of the virus genome segments were targeted preferentially within their upstream sequences and vsiRNAs mapped with higher density to the smaller genome segments than to the medium or larger ones. This tendency, however, was not observed in insects. In both hosts, vsiRNAs were equally derived from sense and antisense RNA strands and the differences in vsiRNAs accumulation did not correlate with mRNAs accumulation. We also established that the piwi-interacting RNA (piRNA pathway was active in the delphacid vector but, contrary to what is observed in virus-infected mosquitoes, virus-specific piRNAs were not detected. This work contributes to the understanding of the silencing response in insect and plant hosts.

  6. Biodegradable Nanoparticles of mPEG-PLGA-PLL Triblock Copolymers as Novel Non-Viral Vectors for Improving siRNA Delivery and Gene Silencing

    Directory of Open Access Journals (Sweden)

    Qiu-Sheng Shi

    2012-01-01

    Full Text Available Degradation of mRNA by RNA interference is one of the most powerful and specific mechanisms for gene silencing. However, insufficient cellular uptake and poor stability have limited its usefulness. Here, we report efficient delivery of siRNA via the use of biodegradable nanoparticles (NPs made from monomethoxypoly(ethylene glycol-poly(lactic-co-glycolic acid-poly-l-lysine (mPEG-PLGA-PLL triblock copolymers. Various physicochemical properties of mPEG-PLGA-PLL NPs, including morphology, size, surface charge, siRNA encapsulation efficiency, and in vitro release profile of siRNA from NPs, were characterized by scanning electron microscope, particle size and zeta potential analyzer, and high performance liquid chromatography. The levels of siRNA uptake and targeted gene inhibition were detected in human lung cancer SPC-A1-GFP cells stably expressing green fluorescent protein. Examination of the cultured SPC-A1-GFP cells with fluorescent microscope and flow cytometry showed NPs loading Cy3-labeled siRNA had much higher intracellular siRNA delivery efficiencies than siRNA alone and Lipofectamine-siRNA complexes. The gene silencing efficiency of mPEG-PLGA-PLL NPs was higher than that of commercially available transfecting agent Lipofectamine while showing no cytotoxicity. Thus, the current study demonstrates that biodegradable NPs of mPEG-PLGA-PLL triblock copolymers can be potentially applied as novel non-viral vectors for improving siRNA delivery and gene silencing.

  7. Biodegradable nanoparticles of mPEG-PLGA-PLL triblock copolymers as novel non-viral vectors for improving siRNA delivery and gene silencing.

    Science.gov (United States)

    Du, Jing; Sun, Ying; Shi, Qiu-Sheng; Liu, Pei-Feng; Zhu, Ming-Jie; Wang, Chun-Hui; Du, Lian-Fang; Duan, You-Rong

    2012-01-01

    Degradation of mRNA by RNA interference is one of the most powerful and specific mechanisms for gene silencing. However, insufficient cellular uptake and poor stability have limited its usefulness. Here, we report efficient delivery of siRNA via the use of biodegradable nanoparticles (NPs) made from monomethoxypoly(ethylene glycol)-poly(lactic-co-glycolic acid)-poly-l-lysine (mPEG-PLGA-PLL) triblock copolymers. Various physicochemical properties of mPEG-PLGA-PLL NPs, including morphology, size, surface charge, siRNA encapsulation efficiency, and in vitro release profile of siRNA from NPs, were characterized by scanning electron microscope, particle size and zeta potential analyzer, and high performance liquid chromatography. The levels of siRNA uptake and targeted gene inhibition were detected in human lung cancer SPC-A1-GFP cells stably expressing green fluorescent protein. Examination of the cultured SPC-A1-GFP cells with fluorescent microscope and flow cytometry showed NPs loading Cy3-labeled siRNA had much higher intracellular siRNA delivery efficiencies than siRNA alone and Lipofectamine-siRNA complexes. The gene silencing efficiency of mPEG-PLGA-PLL NPs was higher than that of commercially available transfecting agent Lipofectamine while showing no cytotoxicity. Thus, the current study demonstrates that biodegradable NPs of mPEG-PLGA-PLL triblock copolymers can be potentially applied as novel non-viral vectors for improving siRNA delivery and gene silencing.

  8. Preintegration HIV-1 inhibition by a combination lentiviral vector containing a chimeric TRIM5 alpha protein, a CCR5 shRNA, and a TAR decoy.

    Science.gov (United States)

    Anderson, Joseph S; Javien, John; Nolta, Jan A; Bauer, Gerhard

    2009-12-01

    Human immunodeficiency virus (HIV) gene therapy offers a promising alternative approach to current antiretroviral treatments to inhibit HIV-1 infection. Various stages of the HIV life cycle including pre-entry, preintegration, and postintegration can be targeted by gene therapy to block viral infection and replication. By combining multiple highly potent anti-HIV transgenes in a single gene therapy vector, HIV-1 resistance can be achieved in transduced cells while prohibiting the generation of escape mutants. Here, we describe a combination lentiviral vector that encodes three highly effective anti-HIV genes functioning at separate stages of the viral life cycle including a CCR5 short hairpin RNA (shRNA) (pre-entry), a human/rhesus macaque chimeric TRIM5 alpha (postentry/preintegration), and a transactivation response element (TAR) decoy (postintegration). The major focus on designing this anti-HIV vector was to block productive infection of HIV-1 and to inhibit any formation of provirus that would maintain the viral reservoir. Upon viral challenge, potent preintegration inhibition of HIV-1 infection was achieved in combination vector-transduced cells in both cultured and primary CD34(+) hematopoietic progenitor cell (HPC)-derived macrophages. The generation of escape mutants was also blocked as evaluated by long-term culture of challenged cells. The ability of this combination anti-HIV lentiviral vector to prevent HIV-1 infection, in vitro, warrants further evaluation of its in vivo efficacy.

  9. Lentivirus vectors construction of SiRNA targeting interferenceGPC3 gene and its biological effects on liver cancer cell lines Huh-7

    Institute of Scientific and Technical Information of China (English)

    Chang-Jiang Lei; Chun Yao; Qing-Yun Pan; Hao-Cheng Long; Lei Li; Shu-Ping Zheng; Cheng Zeng; Jian-Bin Huang

    2014-01-01

    Objective:To buildGPC3 gene short hairpin interferenceRNA(shRNA) slow virus vector, observe expression ofHuh-7GPC3 gene in human liver cell line proliferation apoptosis and the effect ofGPC3 gene influencing on liver cancer cell growth, and provide theoretical basis for gene therapy of liver cancer.Methods:Hepatocellular carcinoma cell lineHuh-7 was transfected by aRNA interference technique.GPC3 gene expression in a variety of liver cancer cell lines was detected by fluorescence quantitativePCR.TargetedGPC3 gene sequences of small interfering RNA(siRNA)PGC-shRNA-GPC3 were restructured.Stable expression cell lines of siRNA were screened and established with the help of liposomes(lipofectamineTM2000) as carrier transfection of human liver cell lines.In order to validate siRNA interference efficiency,GPC3 siRNA mRNA expression was detected after transfection by usingRT-PCR andWestern blot.The absorbance value of the cells of blank group, untransfection group and transfection group, the cell cycle and cell apoptosis were calculated, and effects ofGPC3 gene onHuh-7 cell proliferation and apoptosis were observed.Results:In the liver cancer cell linesHuh-7,GPC3 gene showed high expression.PGC-shRNA-GPC3 recombinant plasmid was constructed successfully via sequencing validation.Stable recombinant plasmid transfected into liver cancer cell linesHuh-7 can obviously inhibitGPC3 mRNA expression level.Conclusions:The targetedGPC3 siRNA can effectively inhibit the expression ofGPC3.

  10. Effect of MSTN Propeptide and shRNA Co-expression Vector on Proliferation of Skeletal Muscle Satellite Cells

    Institute of Scientific and Technical Information of China (English)

    Feng Lin-he; Wang Xin; Lu Ming; Tong Hui-li; Li Shu-feng; Yan Yun-qin

    2014-01-01

    Myostatin (MSTN) is a negative regulator of skeletal muscle growth, in order to study the effect of inhibition MSTN expression on the proliferation of bovine skeletal muscle satellite cells, we constructed co-expression vector pcDNA3.1-Pro-MSTNshRNA, transfected it into muscle satellite cells by Liposome 2000, and detected cell proliferation changes by CCK-8 method and flow cytometry after 48 h. The expressions of P21 and CDK2 were detected by Western blot and real-time PCR. The results showed that the cell vitality of experimental groups significantly increased than that of the negative control, and cells in S phase also increased significantly (P<0.05). After knocked down MSTN gene, P21 expression decreased (P<0.05), but CDK2 gene expression increased (P<0.05). These results indicated that MSTN gene expression was associated with P21 and CDK2, the proliferation of skeletal muscle satellite cells could be promoted while MSTN was inhibited, which provided a theoretical basis for the study on transgenic cattle.

  11. HIV-1 resistance conferred by siRNA cosuppression of CXCR4 and CCR5 coreceptors by a bispecific lentiviral vector

    Directory of Open Access Journals (Sweden)

    Akkina Ramesh

    2005-01-01

    Full Text Available Abstract Background RNA interference (RNAi mediated by small interfering RNAs (siRNAs has proved to be a highly effective gene silencing mechanism with great potential for HIV/AIDS gene therapy. Previous work with siRNAs against cellular coreceptors CXCR4 and CCR5 had shown that down regulation of these surface molecules could prevent HIV-1 entry and confer viral resistance. Since monospecific siRNAs targeting individual coreceptors are inadequate in protecting against both T cell tropic (X4 and monocyte tropic (R5 viral strains simultaneously, bispecific constructs with dual specificity are required. For effective long range therapy, the bispecific constructs need to be stably transduced into HIV-1 target cells via integrating viral vectors. Results To achieve this goal, lentiviral vectors incorporating both CXCR4 and CCR5 siRNAs of short hairpin design were constructed. The CXCR4 siRNA was driven by a U6 promoter whereas the CCR5 siRNA was driven by an H1 promoter. A CMV promoter driven EGFP reporter gene is also incorporated in the bispecific construct. High efficiency transduction into coreceptor expressing Magi and Ghost cell lines with a concomitant down regulation of respective coreceptors was achieved with lentiviral vectors. When the siRNA expressing transduced cells were challenged with X4 and R5 tropic HIV-1, they demonstrated marked viral resistance. HIV-1 resistance was also observed in bispecific lentiviral vector transduced primary PBMCs. Conclusions Both CXCR4 and CCR5 coreceptors could be simultaneously targeted for down regulation by a single combinatorial lentiviral vector incorporating respective anti-coreceptor siRNAs. Stable down regulation of both the coreceptors protects cells against infection by both X4 and R5 tropic HIV-1. Stable down regulation of cellular molecules that aid in HIV-1 infection will be an effective strategy for long range HIV gene therapy.

  12. Structure-property relationship for in vitro siRNA delivery performance of cationic 2-hydroxypropyl-β-cyclodextrin: PEG-PPG-PEG polyrotaxane vectors.

    Science.gov (United States)

    Badwaik, Vivek D; Aicart, Emilio; Mondjinou, Yawo A; Johnson, Merrell A; Bowman, Valorie D; Thompson, David H

    2016-04-01

    Nanoparticle-mediated siRNA delivery is a promising therapeutic approach, however, the processes required for transport of these materials across the numerous extracellular and intracellular barriers are poorly understood. Efficient delivery of siRNA-containing nanoparticles would ultimately benefit from an improved understanding of how parameters associated with these barriers relate to the physicochemical properties of the nanoparticle vectors. We report the synthesis of three Pluronic(®)-based, cholesterol end-capped cationic polyrotaxanes (PR(+)) threaded with 2-hydroxypropyl-β-cyclodextrin (HPβCD) for siRNA delivery. The biological data showed that PR(+):siRNA complexes were well tolerated (∼90% cell viability) and produced efficient silencing (>80%) in HeLa-GFP and NIH 3T3-GFP cell lines. We further used a multi-parametric approach to identify relationships between the PR(+) structure, PR(+):siRNA complex physical properties, and biological activity. Small angle X-ray scattering and cryoelectron microscopy studies reveal periodicity and lamellar architectures for PR(+):siRNA complexes, whereas the biological assays, ζ potential measurements, and imaging studies suggest that silencing efficiency is influenced by the effective charge ratio (ρeff), polypropylene oxide (PO) block length, and central PO block coverage (i.e., rigidity) of the PR(+) core. We infer from our findings that more compact PR(+):siRNA nanostructures arising from lower molecular weight, rigid rod-like PR(+) polymer cores produce improved silencing efficiency relative to higher molecular weight, more flexible PR(+) vectors of similar effective charge. This study demonstrates that PR(+):siRNA complex formulations can be produced having higher performance than Lipofectamine(®) 2000, while maintaining good cell viability and siRNA sequence protection in cell culture.

  13. The promotion of functional recovery and nerve regeneration after spinal cord injury by lentiviral vectors encoding Lingo-1 shRNA delivered by Pluronic F-127.

    Science.gov (United States)

    Wu, Hong-Fu; Cen, Jing-Sheng; Zhong, Qian; Chen, Luming; Wang, Jue; Deng, David Y B; Wan, Yong

    2013-02-01

    Lingo-1 is selectively expressed on both oligodendrocytes and neurons in the central nervous system (CNS) and serves as a key negative regulator of nerve regeneration, implying a therapeutic target for spinal cord injury (SCI). Here we described a strategy to knock-down Lingo-1 expression in vivo using lentiviral vectors encoding Lingo-1 short harpin interfering RNA (shRNA) delivered by Pluronic F-127 (PF-127) gel, a non-cytotoxic scaffold and gene delivery carrier, after the complete transection of the T10 spinal cord in adult rats. We showed administration of PF-127 encapsulating Lingo-1 shRNA lentiviral vectors efficiently down-regulated the expression of Lingo-1, and exhibited transduction efficiency comparable to using vectors alone in oligodendrocyte culture in vitro. Furthermore, similar silencing effects and higher transfection efficiency were observed in vivo when Lingo-1 shRNA was co-delivered to the injured site by PF-127 gel with lower viral concentrations. Cografting of gel and Lingo-1 RNAi significantly promoted functional recovery and nerve regeneration, enhanced neurite outgrowth and synapses formation, preserved myelinated axons, and induced the proliferation of glial cells. In addition, the combined implantation also improved neuronal survival and inhibited cell apoptosis, which may be associated with the attenuation of endoplasmic reticulum (ER) stress after SCI. Together, our data indicated that delivering Lingo-1 shRNA by gel scaffold was a valuable treatment approach to SCI and PF-127 delivery of viral vectors to the spinal cord may provide strategy to study and develop therapies for SCI.

  14. The closterovirus-derived gene expression and RNA interference vectors as tools for research and plant biotechnology

    Science.gov (United States)

    Dolja, Valerian V.; Koonin, Eugene V.

    2013-01-01

    Important progress in understanding replication, interactions with host plants, and evolution of closteroviruses enabled engineering of several vectors for gene expression and virus-induced gene silencing. Due to the broad host range of closteroviruses, these vectors expanded vector applicability to include important woody plants such as citrus and grapevine. Furthermore, large closterovirus genomes offer genetic capacity and stability unrivaled by other plant viral vectors. These features provided immense opportunities for using closterovirus vectors for the functional genomics studies and pathogen control in economically valuable crops. This review briefly summarizes advances in closterovirus research during the last decade, explores the relationships between virus biology and vector design, and outlines the most promising directions for future application of closterovirus vectors. PMID:23596441

  15. Inhibition of cervical cancer cell growth in vitro and in vivo with lentiviral-vector delivered short hairpin RNA targeting human papillomavirus E6 and E7 oncogenes.

    Science.gov (United States)

    Gu, W; Putral, L; Hengst, K; Minto, K; Saunders, N A; Leggatt, G; McMillan, N A J

    2006-11-01

    In this study, we investigated the suppressive effect of a short hairpin RNA delivered by a lentiviral vector (LV-shRNA) against human papillomavirus (HPV) type 18 E6 on the expression of the oncogenes E6 and E7 in cervical cancer HeLa cells both in vitro and in vivo. The LV-shRNA effectively delivered the shRNA to HeLa cells and lead to a dose-dependent reduction of E7 protein and the stabilization of E6 target proteins, p53 and p21. Low-dose infection of HeLa cells with LV-shRNA caused reduced cell growth and the induction of senescence, whereas a high-dose infection resulted in specific cell death via apoptosis. Transplant of HeLa cells infected with a low dose of LV-shRNA into Rag-/- mice significantly reduced the tumor weight, whereas transplant of cells infected with a high dose resulted in a complete loss of tumor growth. Systemic delivery of LV-shRNA into mice with established HeLa cell lung metastases led to a significant reduction in the number of tumor nodules. Our data collectively suggest that lentiviral delivery is an effective way to achieve stable suppression of E6/E7 oncogene expression and induce inhibition of tumor growth both in vitro and in vivo. These results encourage further investigation of this form of RNA interference as a promising treatment for cervical cancer.

  16. Complementation of a primer binding site-impaired murine leukemia virus-derived retroviral vector by a genetically engineered tRNA-like primer

    DEFF Research Database (Denmark)

    Lund, Anders Henrik; Duch, M; Lovmand, J

    1997-01-01

    , but not with a noncomplementary tRNA-like molecule. The engineered primer was shown to be involved in both the initiation of first-strand synthesis and second-strand transfer. These results provide an in vivo demonstration that the retroviral replication machinery may recognize sequence complementarity rather than actual primer...... binding site and 3' primer sequences. Use of mutated primer binding site vectors replicating via engineered primers may add additional control features to retroviral gene transfer technology....

  17. A Comparison of Target Gene Silencing using Synthetically Modified siRNA and shRNA That Express Recombinant Lentiviral Vectors.

    Science.gov (United States)

    Spirin, P V; Baskaran, D; Rubtsov, P M; Zenkova, M A; Vlassov, V V; Chernolovskaya, E L; Prassolov, V S

    2009-07-01

    RNA-interference is an effective natural mechanism of post-transcriptional modulation of gene expression. RNA-interference mechanism exist as in high eukaryotes both animals and plants as well in lower eukaryotes and viruses. RNA-interference is now used as a powerful tool in study of functional gene activity and many essential for fundamental biology results was obtained with this approach. Also it's widely believed that RNA-interference could be used in working out of new therapeutic medicine against malignant, infectious and hereditary diseases. One of the main problems of these developments is search of effective methods of siRNA transfer into the target cells. At present time for these purpose different sorts of transfect ions or viral transduction are used. At present article the results of comparison of inhibition of expression of oncogene AML-ET O by synthetic siRNA and by recombinant lentiviruses coding for corresponding shRNA are presented.

  18. The development of an efficient multipurpose bean pod mottle virus viral vector set for foreign gene expression and RNA silencing.

    Science.gov (United States)

    Zhang, Chunquan; Bradshaw, Jeffrey D; Whitham, Steven A; Hill, John H

    2010-05-01

    Plant viral vectors are valuable tools for heterologous gene expression, and because of virus-induced gene silencing (VIGS), they also have important applications as reverse genetics tools for gene function studies. Viral vectors are especially useful for plants such as soybean (Glycine max) that are recalcitrant to transformation. Previously, two generations of bean pod mottle virus (BPMV; genus Comovirus) vectors have been developed for overexpressing and silencing genes in soybean. However, the design of the previous vectors imposes constraints that limit their utility. For example, VIGS target sequences must be expressed as fusion proteins in the same reading frame as the viral polyprotein. This requirement limits the design of VIGS target sequences to open reading frames. Furthermore, expression of multiple genes or simultaneous silencing of one gene and expression of another was not possible. To overcome these and other issues, a new BPMV-based vector system was developed to facilitate a variety of applications for gene function studies in soybean as well as in common bean (Phaseolus vulgaris). These vectors are designed for simultaneous expression of multiple foreign genes, insertion of noncoding/antisense sequences, and simultaneous expression and silencing. The simultaneous expression of green fluorescent protein and silencing of phytoene desaturase shows that marker gene-assisted silencing is feasible. These results demonstrate the utility of this BPMV vector set for a wide range of applications in soybean and common bean, and they have implications for improvement of other plant virus-based vector systems.

  19. Stable Delivery of CCR5-Directed shRNA into Human Primary Peripheral Blood Mononuclear Cells and Hematopoietic Stem/Progenitor Cells via a Lentiviral Vector

    Science.gov (United States)

    Shimizu, Saki; Yadav, Swati Seth; An, Dong Sung

    2016-01-01

    RNAi is a powerful tool to achieve suppression of a specific gene expression and therefore it has tremendous potential for gene therapy applications. A number of vector systems have been developed to express short-hairpin RNAs (shRNAs) to produce siRNAs within mammalian T-cells, primary hematopoietic stem/progenitor cells (HSPC), human peripheral blood mononuclear cells, and in animal model systems. Among these, vectors based on lentivirus backbones have significantly transformed our ability to transfer shRNAs into nondividing cells, such as HSPC, resulting in high transduction efficiencies. However, delivery and long-term expression of shRNAs should be carefully optimized for efficient knock down of target gene without causing cytotoxicity in mammalian cells. Here, we describe our protocols for the development of shRNA against a major HIV co-receptor/chemokine receptor CCR5 and the use of lentiviral vectors for stable shRNA delivery and expression in primary human PBMC and HSPC. PMID:26472455

  20. A novel method for the quantification of adeno-associated virus vectors for RNA interference applications using quantitative polymerase chain reaction and purified genomic adeno-associated virus DNA as a standard.

    Science.gov (United States)

    Wagner, Anke; Röhrs, Viola; Kedzierski, Radoslaw; Fechner, Henry; Kurreck, Jens

    2013-12-01

    Recombinant adeno-associated virus (rAAV) vectors are promising tools in gene therapy, but accurate quantification of the vector dose remains a critical issue for their successful application. We therefore aimed at the precise determination of the titer of self-complementary AAV (scAAV) vectors to improve the reliability of RNA interference (RNAi)-mediated knockdown approaches. Vector titers were initially determined by quantitative polymerase chain reaction (qPCR) using four primer sets targeting different regions within the AAV vector genome (VG) and either coiled or linearized plasmid standards. Despite very low variability between replicates in each assay, these quantification experiments revealed up to 20-fold variation in vector titers. Therefore, we developed a novel approach for the reproducible determination of titers of scAAV vectors based on the use of purified genomic vector DNA as a standard (scAAVStd). Consistent results were obtained in qPCR assays using the four primer sets mentioned above. RNAi-mediated silencing of human cyclophilin B (hCycB) by short hairpin RNA-expressing scAAV vectors was investigated in HeLa cells using two independent vector preparations. We found that the required vector titers for efficient knockdown differed by a factor of 3.5 between both preparations. Hence, we also investigated the number of internalized scAAV vectors, termed transduction units (TUs). TUs were determined by qPCR applying the scAAVStd. Very similar values for 80% hCycB knockdown were obtained for the two AAV vector preparations. Thus, only the determination of TUs, rather than vector concentration, allows for reproducible results in functional analyses using AAV vectors.

  1. Plant microRNA-target interaction identification model based on the integration of prediction tools and support vector machine.

    Directory of Open Access Journals (Sweden)

    Jun Meng

    Full Text Available Confident identification of microRNA-target interactions is significant for studying the function of microRNA (miRNA. Although some computational miRNA target prediction methods have been proposed for plants, results of various methods tend to be inconsistent and usually lead to more false positive. To address these issues, we developed an integrated model for identifying plant miRNA-target interactions.Three online miRNA target prediction toolkits and machine learning algorithms were integrated to identify and analyze Arabidopsis thaliana miRNA-target interactions. Principle component analysis (PCA feature extraction and self-training technology were introduced to improve the performance. Results showed that the proposed model outperformed the previously existing methods. The results were validated by using degradome sequencing supported Arabidopsis thaliana miRNA-target interactions. The proposed model constructed on Arabidopsis thaliana was run over Oryza sativa and Vitis vinifera to demonstrate that our model is effective for other plant species.The integrated model of online predictors and local PCA-SVM classifier gained credible and high quality miRNA-target interactions. The supervised learning algorithm of PCA-SVM classifier was employed in plant miRNA target identification for the first time. Its performance can be substantially improved if more experimentally proved training samples are provided.

  2. Preclinical safety and efficacy of an anti–HIV-1 lentiviral vector containing a short hairpin RNA to CCR5 and the C46 fusion inhibitor

    Directory of Open Access Journals (Sweden)

    Orit Wolstein

    2014-01-01

    Full Text Available Gene transfer has therapeutic potential for treating HIV-1 infection by generating cells that are resistant to the virus. We have engineered a novel self-inactivating lentiviral vector, LVsh5/C46, using two viral-entry inhibitors to block early steps of HIV-1 cycle. The LVsh5/C46 vector encodes a short hairpin RNA (shRNA for downregulation of CCR5, in combination with the HIV-1 fusion inhibitor, C46. We demonstrate here the effective delivery of LVsh5/C46 to human T cell lines, peripheral blood mononuclear cells, primary CD4+ T lymphocytes, and CD34+ hematopoietic stem/progenitor cells (HSPC. CCR5-targeted shRNA (sh5 and C46 peptide were stably expressed in the target cells and were able to effectively protect gene-modified cells against infection with CCR5- and CXCR4-tropic strains of HIV-1. LVsh5/C46 treatment was nontoxic as assessed by cell growth and viability, was noninflammatory, and had no adverse effect on HSPC differentiation. LVsh5/C46 could be produced at a scale sufficient for clinical development and resulted in active viral particles with very low mutagenic potential and the absence of replication-competent lentivirus. Based on these in vitro results, plus additional in vivo safety and efficacy data, LVsh5/C46 is now being tested in a phase 1/2 clinical trial for the treatment of HIV-1 disease.

  3. CCR5 Gene Disruption via Lentiviral Vectors Expressing Cas9 and Single Guided RNA Renders Cells Resistant to HIV-1 Infection

    OpenAIRE

    2014-01-01

    CCR5, a coreceptor for HIV-1 entry, is a major target for drug and genetic intervention against HIV-1. Genetic intervention strategies have knocked down CCR5 expression levels by shRNA or disrupted the CCR5 gene using zinc finger nucleases (ZFN) or Transcription activator-like effector nuclease (TALEN). In the present study, we silenced CCR5 via CRISPR associated protein 9 (Cas9) and single guided RNAs (sgRNAs). We constructed lentiviral vectors expressing Cas9 and CCR5 sgRNAs. We show that a...

  4. Viral Delivery of dsRNA for Control of Insect Agricultural Pests and Vectors of Human Disease: Prospects and Challenges

    Science.gov (United States)

    Kolliopoulou, Anna; Taning, Clauvis N. T.; Smagghe, Guy; Swevers, Luc

    2017-01-01

    RNAi is applied as a new and safe method for pest control in agriculture but efficiency and specificity of delivery of dsRNA trigger remains a critical issue. Various agents have been proposed to augment dsRNA delivery, such as engineered micro-organisms and synthetic nanoparticles, but the use of viruses has received relatively little attention. Here we present a critical view of the potential of the use of recombinant viruses for efficient and specific delivery of dsRNA. First of all, it requires the availability of plasmid-based reverse genetics systems for virus production, of which an overview is presented. For RNA viruses, their application seems to be straightforward since dsRNA is produced as an intermediate molecule during viral replication, but DNA viruses also have potential through the production of RNA hairpins after transcription. However, application of recombinant virus for dsRNA delivery may not be straightforward in many cases, since viruses can encode RNAi suppressors, and virus-induced silencing effects can be determined by the properties of the encoded RNAi suppressor. An alternative is virus-like particles that retain the efficiency and specificity determinants of natural virions but have encapsidated non-replicating RNA. Finally, the use of viruses raises important safety issues which need to be addressed before application can proceed. PMID:28659820

  5. A novel artificial microRNA expressing AAV vector for phospholamban silencing in cardiomyocytes improves Ca2+ uptake into the sarcoplasmic reticulum.

    Directory of Open Access Journals (Sweden)

    Tobias Gröβl

    Full Text Available In failing rat hearts, post-transcriptonal inhibition of phospholamban (PLB expression by AAV9 vector-mediated cardiac delivery of short hairpin RNAs directed against PLB (shPLBr improves both impaired SERCA2a controlled Ca2+ cycling and contractile dysfunction. Cardiac delivery of shPLB, however, was reported to cause cardiac toxicity in canines. Thus we developed a new AAV vector, scAAV6-amiR155-PLBr, expressing a novel engineered artificial microRNA (amiR155-PLBr directed against PLB under control of a heart-specific hybrid promoter. Its PLB silencing efficiency and safety were compared with those of an AAV vector expressing shPLBr (scAAV6-shPLBr from an ubiquitously active U6 promoter. Investigations were carried out in cultured neonatal rat cardiomyocytes (CM over a period of 14 days. Compared to shPLBr, amiR155-PLBr was expressed at a significantly lower level, resulting in delayed and less pronounced PLB silencing. Despite decreased knockdown efficiency of scAAV6-amiR155-PLBr, a similar increase of the SERCA2a-catalyzed Ca2+ uptake into sarcoplasmic reticulum (SR vesicles was observed for both the shPLBr and amiR155-PLBr vectors. Proteomic analysis confirmed PLB silencing of both therapeutic vectors and revealed that shPLBr, but not the amiR155-PLBr vector, increased the proinflammatory proteins STAT3, STAT1 and activated STAT1 phosphorylation at the key amino acid residue Tyr701. Quantitative RT-PCR analysis detected alterations in the expression of several cardiac microRNAs after treatment of CM with scAAV6-shPLBr and scAAV6-amiR155-PLBr, as well as after treatment with its related amiR155- and shRNAs-expressing control AAV vectors. The results demonstrate that scAAV6-amiR155-PLBr is capable of enhancing the Ca2+ transport function of the cardiac SR PLB/SERCA2a system as efficiently as scAAV6-shPLBr while offering a superior safety profile.

  6. A Novel Artificial MicroRNA Expressing AAV Vector for Phospholamban Silencing in Cardiomyocytes Improves Ca2+ Uptake into the Sarcoplasmic Reticulum

    Science.gov (United States)

    Größl, Tobias; Hammer, Elke; Bien-Möller, Sandra; Geisler, Anja; Pinkert, Sandra; Röger, Carsten; Poller, Wolfgang; Kurreck, Jens; Völker, Uwe

    2014-01-01

    In failing rat hearts, post-transcriptonal inhibition of phospholamban (PLB) expression by AAV9 vector-mediated cardiac delivery of short hairpin RNAs directed against PLB (shPLBr) improves both impaired SERCA2a controlled Ca2+ cycling and contractile dysfunction. Cardiac delivery of shPLB, however, was reported to cause cardiac toxicity in canines. Thus we developed a new AAV vector, scAAV6-amiR155-PLBr, expressing a novel engineered artificial microRNA (amiR155-PLBr) directed against PLB under control of a heart-specific hybrid promoter. Its PLB silencing efficiency and safety were compared with those of an AAV vector expressing shPLBr (scAAV6-shPLBr) from an ubiquitously active U6 promoter. Investigations were carried out in cultured neonatal rat cardiomyocytes (CM) over a period of 14 days. Compared to shPLBr, amiR155-PLBr was expressed at a significantly lower level, resulting in delayed and less pronounced PLB silencing. Despite decreased knockdown efficiency of scAAV6-amiR155-PLBr, a similar increase of the SERCA2a-catalyzed Ca2+ uptake into sarcoplasmic reticulum (SR) vesicles was observed for both the shPLBr and amiR155-PLBr vectors. Proteomic analysis confirmed PLB silencing of both therapeutic vectors and revealed that shPLBr, but not the amiR155-PLBr vector, increased the proinflammatory proteins STAT3, STAT1 and activated STAT1 phosphorylation at the key amino acid residue Tyr701. Quantitative RT-PCR analysis detected alterations in the expression of several cardiac microRNAs after treatment of CM with scAAV6-shPLBr and scAAV6-amiR155-PLBr, as well as after treatment with its related amiR155- and shRNAs-expressing control AAV vectors. The results demonstrate that scAAV6-amiR155-PLBr is capable of enhancing the Ca2+ transport function of the cardiac SR PLB/SERCA2a system as efficiently as scAAV6-shPLBr while offering a superior safety profile. PMID:24670775

  7. Cloning of strawberry FaEtr2 gene and its plant expression vector construction for antisense RNA

    Institute of Scientific and Technical Information of China (English)

    Chunli SONG; Junlian MA; Xia TANG; Zide ZHANG; Pingping ZHOU; Zhixia HOU

    2009-01-01

    An ethylene receptor FaEtr2 gene was amplified by polymerase chain reaction (PCR) from ripening strawberry fruit. A 1049-bp PCR product (All Star-Etr2) was cloned. Sequence analysis showed that the All Star-Etr2 nucleotide sequence had 100% identity with Chandler-Etr2 from the GenBank. A pair of primers containing restriction enzyme sites were designed and used to amplify the sequenced plasmid. The PCR product was digested by the corresponding restricted enzymes and inserted between the CaMV 35S promoter and NOS terminator of expression vector pBI121 directionally. The constructed expression vector was transformed into Agrobacterium fumefeciens LBA4404 in the follow-up research to silence a ripening-related ethylene receptor FaEtr2 gene in strawberry fruits.

  8. Involvement of RNA2-encoded proteins in the specific transmission of Grapevine fanleaf virus by its nematode vector Xiphinema index.

    Science.gov (United States)

    Belin, C; Schmitt, C; Demangeat, G; Komar, V; Pinck, L; Fuchs, M

    2001-12-01

    The nepovirus Grapevine fanleaf virus (GFLV) is specifically transmitted by the nematode Xiphinema index. To identify the RNA2-encoded proteins involved in X. index-mediated spread of GFLV, chimeric RNA2 constructs were engineered by replacing the 2A, 2B(MP), and/or 2C(CP) sequences of GFLV with their counterparts in Arabis mosaic virus (ArMV), a closely related nepovirus which is transmitted by Xiphinema diversicaudatum but not by X. index. Among the recombinant viruses obtained from transcripts of GFLV RNA1 and chimeric RNA2, only those which contained the 2C(CP) gene (504 aa) and 2B(MP) contiguous 9 C-terminal residues of GFLV were transmitted by X. index as efficiently as natural and synthetic wild-type GFLV, regardless of the origin of the 2A and 2B(MP) genes. As expected, ArMV was not transmitted probably because it is not retained by X. index. These results indicate that the determinants responsible for the specific spread of GFLV by X. index are located within the 513 C-terminal residues of the polyprotein encoded by RNA2.

  9. USP22 ShRNA慢病毒载体的构建及鉴定%Construction and identification of ShRNA lentivirus vector in gene USP22

    Institute of Scientific and Technical Information of China (English)

    余宏伟; 廖志伟; 庄雅靖; 喻芳; 周同冲

    2014-01-01

    目的:构建并鉴定USP22基因ShRNA慢病毒载体,为进一步研究USP22基因在鼻咽癌中的作用机制奠定基础。方法针对USP22基因的编码序列设计并合成2条特异性干扰序列,序列两端含有限制性内切酶位点HpaⅠ和X hoⅠ。寡核苷酸链退火生成寡核苷酸双链,5'端磷酸化后将含有酶切位点的寡核苷酸双链克隆到pLL3.7慢病毒表达载体。连接产物经转化、培养,提取其质粒,提取出来的质粒经HpaⅠ和XhoⅠ酶切电泳鉴定,鉴定正确的质粒进行测序。构建成功的慢病毒表达载体pLL-USP22-shRNA与包装载体质粒混匀共转染于293T细胞。通过荧光显微镜下观察绿色荧光蛋白(GFP)情况,对病毒滴度和感染效率进行检测。结果成功构建慢病毒表达载体pLL-USP22-shRNA。与包装载体质粒共转染293T细胞后测定慢病毒滴度为4×107 TU/ml。结论本实验应用相关技术成功构建USP22 ShRNA慢病毒载体,为进一步研究USP22基因的生物学功能奠定了基础。%Objective To construct and identify ShRNA lentivirus vector in gene USP22,and lay the foundation for fur-ther study of gene USP22 on mechanism of nasopharyngeal carcinoma. Methods Two special interference sequences targeting on coded sequence of gene USP22 were designed and synthesized.HpaⅠand XhoⅠas two sites of restriction enzyme were included at both ends of the sequence.Oligodeoxynucleotides was annealed to generate double strands of oligodeoxynucleotides.After 5’end phosphorylation,double strands of oligodeoxynucleotides containing restriction enzyme cutting site was cloned to pLentiLox3.7 (PLL3.7) lentiviral expression vector.The connection product was transformed and cultivated in order to extract plasmid.The extracted plasmid was identified by restriction enzyme digestion and electrophoresis,and sequencing was carried on only for correct plasmid after identification.The successfully-constructed lentiviral expression vector of p

  10. Preparation of Inert Polystyrene Latex Particles as MicroRNA Delivery Vectors by Surfactant-Free RAFT Emulsion Polymerization.

    Science.gov (United States)

    Poon, Cheuk Ka; Tang, Owen; Chen, Xin-Ming; Pham, Binh T T; Gody, Guillaume; Pollock, Carol A; Hawkett, Brian S; Perrier, Sébastien

    2016-03-14

    We present the preparation of 11 nm polyacrylamide-stabilized polystyrene latex particles for conjugation to a microRNA model by surfactant-free RAFT emulsion polymerization. Our synthetic strategy involved the preparation of amphiphilic polyacrylamide-block-polystyrene copolymers, which were able to self-assemble into polymeric micelles and "grow" into polystyrene latex particles. The surface of these sterically stabilized particles was postmodified with a disulfide-bearing linker for the attachment of the microRNA model, which can be released from the latex particles under reducing conditions. These nanoparticles offer the advantage of ease of preparation via a scaleable process, and the versatility of their synthesis makes them adaptable to a range of applications.

  11. Silencing of hepatitis C virus replication by a non-viral vector based on solid lipid nanoparticles containing a shRNA targeted to the internal ribosome entry site (IRES).

    Science.gov (United States)

    Torrecilla, Josune; Del Pozo-Rodríguez, Ana; Solinís, María Ángeles; Apaolaza, Paola S; Berzal-Herranz, Beatriz; Romero-López, Cristina; Berzal-Herranz, Alfredo; Rodríguez-Gascón, Alicia

    2016-10-01

    Gene silencing mediated by RNAi has gained increasing interest as an alternative for the treatment of infectious diseases such as refractory hepatitis C virus (HCV) infection. In this work we have designed and evaluated a non-viral vector based on solid lipid nanoparticles (SLN) bearing hyaluronic acid, protamine and a short hairpin RNA (shRNA74) targeted to the Internal Ribosome Entry Site (IRES) of the HCV. The vector was able to inhibit the expression of the HCV IRES in Huh-7 cells, with the inhibition level dependent on the shRNA74 to SLN ratio and on the shRNA74 dose added to the culture cells. The nanocarrier was also able to inhibit the replication in human hepatoma cells supporting a subgenomic HCV replicon (Huh-7 NS3-3'). The vector was quickly and efficiently internalized by the cells, and endocytosis was the most productive uptake mechanism for silencing. Clathrin-mediated endocytosis and to a lesser extent caveolae/lipid raft-mediated endocytosis were identified as endocytic mechanisms involved in the cell uptake. Internalization via the CD44 receptor was also involved, although this entry route seems to be less productive for silencing than endocytosis. The vector did not induce either hemolysis or agglutination of red cells in vitro, which was indicative of good biocompatibility. In summary, we have shown for the first time the ability of a non-viral SLN-based vector to silence a HCV replicon.

  12. STAT3基因 siRNA 表达载体的构建及鉴定%The Building and Identification of siRNA STAT3 Gene Expression Vector

    Institute of Scientific and Technical Information of China (English)

    刘洋; 靳秋月; 段美庆; 樊淑珍; 陈立军

    2015-01-01

    Objective This study used RNA interference technology,selected STAT3 gene as the tar-get,and then design and construction a recombinant vector and then identification the gene sequence analy-sis.Methods Design a DNA sequence with a small hairpin structure,PCR amplification a siRNA expression cassettes,cloning vector to construct recombinants in psiLentGeneTM into E.coli DH5αstrain,extract plas-mid after enzyme digestion sequencing.Results Recombinant plasmid by EcoR Ⅴ enzyme,electrophoresis and Sequencing analysis showed that the inserted sequence is correct,the recombinant plasmids were success-fully constructed.Conclusion The successful construction of STAT3 targeted RNA interference recombi-nant,provides some new methods for gene therapy of cancer research at the molecular level,cellular level and the overall level of.%目的:利用RNA干扰技术,以信号转导和转录激活因子3(STAT3)为靶基因,设计构建重组体,并进行序列分析鉴定。方法设计一条有小发夹结构的 DNA 序列,聚合酶链反应( PCR)扩增合成 siRNA 表达框架(SECs)表达框架,克隆至载体 psiLentGeneTM 中构建重组体,转化 E.coli DH5α菌株,提取质粒进行酶切鉴定后测序分析。结果重组质粒经 EcoRⅤ酶切、电泳、测序分析表明插入序列正确,重组质粒构建成功。结论成功构建了 STAT3靶向 RNA 干扰重组体,为肿瘤的基因治疗在分子水平、细胞水平和整体水平的研究提供一些新方法。

  13. CCR5 gene disruption via lentiviral vectors expressing Cas9 and single guided RNA renders cells resistant to HIV-1 infection.

    Science.gov (United States)

    Wang, Weiming; Ye, Chaobaihui; Liu, Jingjing; Zhang, Di; Kimata, Jason T; Zhou, Paul

    2014-01-01

    CCR5, a coreceptor for HIV-1 entry, is a major target for drug and genetic intervention against HIV-1. Genetic intervention strategies have knocked down CCR5 expression levels by shRNA or disrupted the CCR5 gene using zinc finger nucleases (ZFN) or Transcription activator-like effector nuclease (TALEN). In the present study, we silenced CCR5 via CRISPR associated protein 9 (Cas9) and single guided RNAs (sgRNAs). We constructed lentiviral vectors expressing Cas9 and CCR5 sgRNAs. We show that a single round transduction of lentiviral vectors expressing Cas9 and CCR5 sgRNAs into HIV-1 susceptible human CD4+ cells yields high frequencies of CCR5 gene disruption. CCR5 gene-disrupted cells are not only resistant to R5-tropic HIV-1, including transmitted/founder (T/F) HIV-1 isolates, but also have selective advantage over CCR5 gene-undisrupted cells during R5-tropic HIV-1 infection. Importantly, using T7 endonuclease I assay we did not detect genome mutations at potential off-target sites that are highly homologous to these CCR5 sgRNAs in stably transduced cells even at 84 days post transduction. Thus we conclude that silencing of CCR5 via Cas9 and CCR5-specific sgRNAs could be a viable alternative strategy for engineering resistance against HIV-1.

  14. Enhancement of RNA-directed DNA methylation of a transgene by simultaneously downregulating a ROS1 orthologue using a virus vector in Nicotiana benthamiana

    Directory of Open Access Journals (Sweden)

    Shungo eOtagaki

    2013-04-01

    Full Text Available Cytosine methylation can be induced by double-stranded RNAs through the RNA-directed DNA methylation (RdDM pathway. A DNA glycosylase REPRESSOR OF SILENCING 1 (ROS1 participates in DNA demethylation in Arabidopsis and may possibly counteract RdDM. Here, we isolated an orthologue of ROS1 (NbROS1 from Nicotiana benthamiana and examined the antagonistic activity of NbROS1 against virus-induced RdDM by simultaneously inducing RdDM and NbROS1 knockdown using a vector based on Cucumber mosaic virus. Plants were inoculated with a virus that contained a portion of the CaMV 35S promoter, which induced RdDM of the promoter integrated in the plant genome and transcriptional silencing of the green fluorescent protein gene driven by the promoter. Plants were also inoculated with a virus that contained a portion of NbROS1, which induced downregulation of NbROS1. Simultaneous induction of RdDM and NbROS1 knockdown resulted in an increase in the level of cytosine methylation of the target promoter. These results provide evidence for the presence of antagonistic activity of NbROS1 against virus-induced RdDM and suggest that the simultaneous induction of promoter-targeting RdDM and NbROS1 knockdown by a virus vector is useful as a tool to enhance targeted DNA methylation.

  15. CCR5 gene disruption via lentiviral vectors expressing Cas9 and single guided RNA renders cells resistant to HIV-1 infection.

    Directory of Open Access Journals (Sweden)

    Weiming Wang

    Full Text Available CCR5, a coreceptor for HIV-1 entry, is a major target for drug and genetic intervention against HIV-1. Genetic intervention strategies have knocked down CCR5 expression levels by shRNA or disrupted the CCR5 gene using zinc finger nucleases (ZFN or Transcription activator-like effector nuclease (TALEN. In the present study, we silenced CCR5 via CRISPR associated protein 9 (Cas9 and single guided RNAs (sgRNAs. We constructed lentiviral vectors expressing Cas9 and CCR5 sgRNAs. We show that a single round transduction of lentiviral vectors expressing Cas9 and CCR5 sgRNAs into HIV-1 susceptible human CD4+ cells yields high frequencies of CCR5 gene disruption. CCR5 gene-disrupted cells are not only resistant to R5-tropic HIV-1, including transmitted/founder (T/F HIV-1 isolates, but also have selective advantage over CCR5 gene-undisrupted cells during R5-tropic HIV-1 infection. Importantly, using T7 endonuclease I assay we did not detect genome mutations at potential off-target sites that are highly homologous to these CCR5 sgRNAs in stably transduced cells even at 84 days post transduction. Thus we conclude that silencing of CCR5 via Cas9 and CCR5-specific sgRNAs could be a viable alternative strategy for engineering resistance against HIV-1.

  16. RNAi表达载体在哺乳动物中的研究进展%Research Progress of RNA Interference Expression Vector in Mammals

    Institute of Scientific and Technical Information of China (English)

    侯莹; 成志云; 王立强; 许瑞安; 唐明青

    2015-01-01

    This paper reviewed the non-biological and biological delivery systerms of RNA interference expression vector as well as the major applications,and cleared the application prospect in the area of gene regulation and gene therapy in the future,and also pointed out the limitation in the species-specificity and expression efficiency etc.This paper summa-rized and analyzed the structure composition and development evolution of the RNAi expression vector as well as the func-tion mechanism invivo,and proposed the classification based on the dual attributes of structure composition and process-ing mechanism.%对RNA干扰(RNAi)表达载体的非生物与生物递送系统及主流应用进行综述,明确其在基因调控及未来基因治疗领域的应用前景,并指出其在种属特异性及表达效率等方面存在的局限性。对RNAi 表达载体的结构组成、发展沿革及体内作用机制进行归纳分析,提出基于结构组成和加工机制双重属性的分类方法。

  17. Successful disabling of the 5' UTR of HCV using adeno-associated viral vectors to deliver modular multimeric primary microRNA mimics.

    Science.gov (United States)

    Bourhill, Tarryn; Arbuthnot, Patrick; Ely, Abdullah

    2016-09-01

    Chronic hepatitis C virus (HCV) infection is a major health concern and is strongly associated with cirrhosis, hepatocellular carcinoma and liver-related mortality. The HCV genome is the template for both protein translation and viral replication and, being RNA, is amenable to direct genetic silencing by RNA interference (RNAi). HCV is a highly mutable virus and is capable of escaping RNAi-mediated silencing. This has highlighted the importance of developing RNAi-based therapy that simultaneously targets multiple regions of the HCV genome. To develop a multi-targeting RNAi activator, a novel approach for the generation of anti-HCV gene therapy was investigated. Five artificial primary miRNA (pri-miR) were each designed to mimic the naturally occurring monomeric pri-miR-31. Potent knockdown of an HCV reporter was seen with four of the five constructs and were processed according to the intended design. The design of the individual pri-miR mimics enabled the modular assembly into multimeric mimics of any possible conformation. Consequently the four potent pri-miR mimics were used to generate polycistronic cassettes, which showed impressive silencing of an HCV target. To further their application as a gene therapy, recombinant adeno-associated viral (rAAV) vectors that express the polycistronic pri-miR mimics were generated. All AAV-delivered anti-HCV pri-miR mimics significantly knocked down the expression of an HCV target and showed inhibition of HCV replicon replication. Here we describe a protocol for the generation of therapeutic rAAVs that express modular polycistronic pri-miR cassettes allowing for rapid alteration and generation of tailored therapeutic constructs against HCV.

  18. Striatal modulation of BDNF expression using microRNA124a-expressing lentiviral vectors impairs ethanol-induced conditioned-place preference and voluntary alcohol consumption.

    Science.gov (United States)

    Bahi, Amine; Dreyer, Jean-Luc

    2013-07-01

    Alcohol abuse is a major health, economic and social concern in modern societies, but the exact molecular mechanisms underlying ethanol addiction remain elusive. Recent findings show that small non-coding microRNA (miRNA) signaling contributes to complex behavioral disorders including drug addiction. However, the role of miRNAs in ethanol-induced conditioned-place preference (CPP) and voluntary alcohol consumption has not yet been directly addressed. Here, we assessed the expression profile of miR124a in the dorsal striatum of rats upon ethanol intake. The results show that miR124a was downregulated in the dorso-lateral striatum (DLS) following alcohol drinking. Then, we identified brain-derived neurotrophic factor (BDNF) as a direct target of miR124a. In fact, BDNF mRNA was upregulated following ethanol drinking. We used lentiviral vector (LV) gene transfer technology to further address the role of miR124a and its direct target BDNF in ethanol-induced CPP and alcohol consumption. Results reveal that stereotaxic injection of LV-miR124a in the DLS enhances ethanol-induced CPP as well as voluntary alcohol consumption in a two-bottle choice drinking paradigm. Moreover, miR124a-silencer (LV-siR124a) as well as LV-BDNF infusion in the DLS attenuates ethanol-induced CPP as well as voluntary alcohol consumption. Importantly, LV-miR124a, LV-siR124a and LV-BDNF have no effect on saccharin and quinine intake. Our findings indicate that striatal miR124a and BDNF signaling have crucial roles in alcohol consumption and ethanol conditioned reward.

  19. Introducing Vectors.

    Science.gov (United States)

    Roche, John

    1997-01-01

    Suggests an approach to teaching vectors that promotes active learning through challenging questions addressed to the class, as opposed to subtle explanations. Promotes introducing vector graphics with concrete examples, beginning with an explanation of the displacement vector. Also discusses artificial vectors, vector algebra, and unit vectors.…

  20. 人TR基因真核表达载体的构建%Construction of eukaryotic expression vector of human telomerase RNA component and its function

    Institute of Scientific and Technical Information of China (English)

    营孙阳; 熊加秀; 麦洪旭; 林佳佳; 姜丽娜; 程龙; 叶棋浓

    2016-01-01

    目的 构建人端粒酶RNA组分( hTR)的真核表达载体,并对其生物学功能进行初步检测. 方法 以人胚肾293 T细胞RNA逆转录得到的cDNA为模板,采用PCR技术扩增出hTR编码序列,将其插入到pCDNA 3 .0载体中;将重组质粒与空载体分别转染293T细胞,实时荧光定量PCR(real-time quantitative PCR, qRT-PCR)检测其表达情况,在HepG2细胞中构建此基因的稳定细胞系并用qRT-PCR检测其效果,通过RNA结合免疫共沉淀( RIP )实验验证其和人端粒酶逆转录酶( hTERT )及角化不良蛋白( dyskerin )的相互作用,通过端粒酶重复序列扩增技术( telomerase repeat amplification protocol ,TRAP)检测过表达hTR后HepG2细胞的端粒酶活性. 结果 双酶切和测序结果表明,pCDNA3.0-hTR的真核表达载体构建成功;转染293T细胞用qRT-PCR证明成功表达;qRT-PCR证实HepG2 pCDNA3.0-hTR稳定细胞系筛选成功;RIP实验证实了hTR与hTERT和角化不良蛋白之间存在相互作用;TRAP实验发现过表达hTR并不影响HepG2细胞的端粒酶活性. 结论 成功构建了pCDNA 3.0-hTR真核表达载体,为进一步研究以针对hTR为靶标的癌症治疗奠定了基础.%Objective To construct the eukaryotic expression vector of human telomerase RNA component ( hTR) and study its biological function tentatively .Methods hTR Gene was obtained by PCR from cDNA template , which was reverse transcribed from 293T mRNA and cloned into pCDNA3.0 vector.The recombinant plasmid and empty vector were trans-fected into 293T cells, and hTR expression was identified by qRT-PCR.HepG2 cells that stably transfected with pCDNA3.0-hTR were constructed and identified by qRT-PCR.These cells were used to assess the interaction of hTR with human telomerase revese transcriptase ( hTERT ) and dyskerin .Telomerase activity was also detected in HepG 2 cells transfected with pCDNA3.0-hTR.Results pCDNA3.0-hTR eukaryotic expression vector was successfully constructed by double digestion

  1. 人神经菌毛素-1基因shRNA慢病毒载体的构建%Construction of recombinant lentiviral vector containing shRNA for human neuropilin-1 gene

    Institute of Scientific and Technical Information of China (English)

    郑见宝; 耿智敏; 陈强; 王林

    2012-01-01

    AIM; To construct and identify a recombi-nant lentiviral vector containing shRNA for human neuropilin-1 (NRP-1) gene. METHODS: Four shRNA targeting the NRP-1 mRNA were designed to construct the pGCSIL-RFP-shNRP1 lentivirus vectors. The positive clone was chosen and confirmed by PCR and DNA sequencing. 293T cells were cotransfected with pGCSIL-RFP-shNRP1, pHelperl.0 and pHelper 2.0 to package the lentivirus and the titer of the virus was tested. After lentivirus-shRNA and over-expression plasmid containing NRP-1 were transfected into 293T cells, Western blotting was used to determine the expression of Flag gene in order to observe the inhibited efficacy of relative NRP-1 expression. RESULTS: PCR analysis and DNA sequencing demonstrated that the shRNA sequence was consistent with the human NRP-1. The titer of the recombinant lentiviral vector was 1×10-9 Tu/mL The relative expression of NRP-1 protein in the transfected cells significantly decreased after treated with lentiviral-shRNA. CONCLUSION: We have constructed successfully the effective recombinant lentiviral vector containing shRNA for human NRP-1 gene.%目的:构建并鉴定靶向人神经菌毛素-1(NRP-1)基因的小发卡RNA的慢病毒载体.方法:针对NRP-1mRNA设计了4条shRNA,并构建pGCSIL-RFP-shNRP1慢病毒质粒,PCR扩增阳性克隆并测序鉴定.用pGCSIL-RFP-shNRP1、pHelper1.0和pHelper2.0质粒共转染293T细胞包装产生慢病毒,测定病毒滴度.将慢病毒干扰RNA及含有NRP-1过表达载体共转染293T细胞,Western blot法检测Flag表达,观察NRP-1蛋白相对表达抑制效果.结果:PCR和测序结果与设计的干扰序列一致,病毒滴度达1×109 Tu/mL.转染细胞中NRP-1蛋白相对表达显著降低.结论:成功构建了高效率的人NRP-1基因shRNA慢病毒载体.

  2. Construction of a microRNA expressing eukaryotic vector targeting vascular endothelial growth Factor%靶向血管内皮生长因子基因的微小RNA真核表达载体的构建

    Institute of Scientific and Technical Information of China (English)

    熊建宁; 孙建; 区应亮; 简志祥

    2012-01-01

    背景:有研究表明微小RNA 及潜在靶基因在肝癌中起重要作用,但具体机制仍不清楚.目的:构建靶向血管内皮生长因子基因微小RNA 真核表达载体,评估其转染人肝癌细胞株HepG2 后血管内皮生长因子基因的干扰效果.方法:根据血管内皮生长因子序列设计合成4 对微小RNA 不同干扰片段,克隆到pcDNA6.2-GW/EmGFP-微小RNA 真核表达载体上,测序分析鉴定插入序列的完整性;并将其转染至HepG-2 细胞株中.采用实时荧光定量聚合酶链式反应分析血管内皮生长因子微小RNA 干扰效果,蛋白印迹技术测定重组体对血管内皮生长因子基因蛋白表达情况.结果与结论:构建的4 组重组体插入片段的碱基序列完全正确,重组体能干扰肝癌细胞HepG2 细胞血管内皮因子基因的表达,4 组重组体基因的mRNA 的表达水平和蛋白表达水平与阴性对照组相比明显降低(P < 0.05),其中血管内皮生长因子微小RNA-3 表达水平最低,抑制率87%.结果证实,实验成功构建血管内皮生长因子微小RNA 表达载体,在体外能有效抑制HepG2 细胞血管内皮生长因子基因表达.%BACKGROUND: Studies have shown that the microRNA (miRNA) and its potential target gene play an important role in hepatocellular carcinoma, but the exact mechanism is still unclear. OBJECTIVE: To construct a vascular endothelial growth factor (VEGF) miRNA expressing eukaryotic vector and to identify biological activity of VEGF miRNA transfected into HepG-2 cells. METHODS: According to the sequence of VEGF mRNA, the VEGF miRNA was designed and synthesized, and then cloned into the pcDNA6.2-GW/EmGFP-miRNA vector and transfected into HepG-2 cell lines. The integrity of the insert fragment was detected using colony PCR and sequencing analysis. The biological activity of VEGF miRNA by way of real-time PCR and Western blot was determined. RESULTS AND CONCLUSION: Sequences of the inset fragment in the four miRNA

  3. Construction and expressing activity of microRNA-125a plasmid expression vectors%MicroRNA-125a质粒表达载体的构建及其表达活性

    Institute of Scientific and Technical Information of China (English)

    张涛; 李东; 李华; 高辉

    2012-01-01

    背景:pSuper是一种非编码RNA的真核表达载体,可在细胞质内表达miRNA前体,经过细胞自身的Dicer酶切后形成miRNA成熟体,其过程能够完全模仿细胞内源性miRNA形成过程.因此,利用pSuper表达载体构建一种肝癌抑制性miRNA:miR-125a的表达载体,为下一步研究其抗癌机制奠定了基础.目的:构建miR-125a的真核表达质粒pSuper-miR-125a,并验证其表达miR-125a的效率和特异性.方法:PCR扩增miR-125a前体(Pre-miR-125a)的目的片段,将其T-A克隆入pMD18-T过渡质粒载体,限制性内切酶切下目的片段,连接入pSuper质粒表达载体得到pSuper-miR-125a重组质粒;将重组质粒转染Hela细胞,miRNA定量PCR检测重组质粒表达miR-125a的效率和特异性.结果与结论:成功将miR-125a前体(Pre-miR-125a)片段克隆入真核表达质粒pSuper H1启动子下游,获得pSuper-miR-125a重组表达质粒,转染该质粒进入Hela细胞后能够在细胞内高效和特异的表达miR-125a,进一步证明 pSuper真核表达质粒适合miRNA的表达研究.%BACKGROUND: pSuper is a kind of eukaryotic expression vectors of non-coding RNA. It expresses the precursor of miRNA in plasma, and then the precursor is cut by Dicer enzyme to produce mature miRNA. This process completely imitates the formation process of endogenous miRNA. In this study, pSuper is utilized to construct an expression vector of miR-125a, which could inhibit liver cancer. It provides basis for the further investigation on antitumor mechanism. OBJECTIVE: To construct the eukaryotic plasmid pSuper-miR-125a expressing miR-125a and to confirm the expressing efficiency and specificity of miR-125a in the plasmid. METHODS: Target fragments in the precursor of miR-125a (Pre-miR-125a) were amplified by PCR. The fragments were cloned into pMD18-T transition plasmid using T-A cloning method. The target fragments were cut by restriction enzyme and then connected to pSuper plasmid to construct recombinant plasmid p

  4. 人AQP1-shRN A 表达质粒载体的构建与筛选%Construction and screening of human AQP1 shRNA expression vectors

    Institute of Scientific and Technical Information of China (English)

    李卓; 康炜; 辛娜; 田宇; 李建华

    2015-01-01

    Objective To construct and screen effective shRNA expression vectors targeting human AQP1 gene ,and evaluate the interference efficiency of the AQP1 shRNA recombinant plasmids ,thus provide basis for further exploration on the effect and mechanism of AQP1 gene on human breast cancer cells .Methods Four pairs of shRNA sequences targeting human AQP1 gene were designed and synthesized ,and then inserted into the GV115 vector .AQP1 shRNA and control shRNA plasmids were trans‐fected into human breast cancer MCF‐7 cells .The expression of AQP1 mRNA and protein were detected by real time PCR(RT‐PCR) and Western blot to evaluate the interfering efficiency .Results RT‐PCR demonstrated that AQP1 was expressed in human breast cancer MCF‐7 cells .Sequencing showed that the shRNA vectors targeting AQP1 were successfully constructed .48 h after the AQP1 shRNA transfection ,AQP1 mRNA and protein expression levels in MCF‐7 cells were reduced to a significant degree ,and the AQP1 shRNA 4 plasmid vector could inhibit the AQP1 most efficiently .Conclusion The AQP1 shRNA recombinant plasmids vectors were successfully constructed and can significantly inhibit the expression of AQP1 in MCF‐7 human breast cancer cells .%目的:构建针对人水通道蛋白1(AQP1)基因的shRNA表达质粒载体,并验证其干扰效果,为进一步探讨AQP1基因对人乳腺癌细胞的作用及机制建立基础。方法设计合成4对针对人AQP1基因不同位点的shRNA片段,通过DNA重组技术将其插入载体GV115中,构建AQP1‐shRNA重组质粒,转染人乳腺癌MCF‐7细胞,并通过实时荧光定量 PCR(RT‐PCR)和Western blot法检测干扰效率。结果 RT‐PCR法证实AQP1在乳腺癌 MCF‐7细胞中有表达。测序验证表明4对靶向AQP1‐shRNA表达载体均构建成功。4组干扰载体能够从基因和蛋白表达水平不同程度抑制 AQP1表达,其中以AQP1‐shRNA 4对AQP1的干扰效率最强。结论成功

  5. 靶向人原癌基因c-fos的shRNA表达质粒的构建及鉴定%Construction and Identification of Short Hairpin RNA Expression Vector Targeting to Human Proto-oncogene c-fos

    Institute of Scientific and Technical Information of China (English)

    景志杰; 刘田福; 师锐赞

    2011-01-01

    Objective To construct and identify a short hairpin RNA (shRNA) expression vector targeting to human protooncogene c-fos. Methods Recombinant shRNA expression vector Psilencer3.l-sic-fos targeting to human c-fos gene was constructed and transfected to breast cancer MCF-7 cells. The expression of c-fos mRNA in stably transfected cell was determined by RT-PCR.Results PCR, restriction analysis and sequencing proved that recombinant plasmid Psilencer3. 1-sic-fos was constructed correctly.The recombinant plasmid inhibited the expression of c-fos gene at mRNA level in MCF-7 cells significantly. Conclusion The recombinant shRNA expression vector for human c-fos gene was successfully constructed, which provided a technical tool for further study on the role of c-fos gene in genesis and progress of tumors.%目的 构建靶向人原癌基因c-los的短发夹RNA(Short hairpin RNA,shRNA)重组真核表达质粒,并进行鉴定.方法 构建靶向人c-fos基因的shRNA重组表达质粒Psilencer 3.1-sic-fos,转染乳腺癌MCF-7细胞,采用RT-PCR法检测稳定转染细胞中c-fos基因mRNA的表达.结果 重组表达质粒Psilencer 3.1-sic-fos经PCR、双酶切及测序证明构建正确;重组表达质粒在mRNA水平明显抑制了MCF-7细胞c-fos基因的表达(P<0.05).结论 已成功构建了人c-fos基因shRNA重组表达质粒,为深入研究c-fos基因在肿瘤发生、发展过程中的作用提供了技术手段.

  6. Combination of the somatic cell nuclear transfer method and RNAi technology for the production of a prion gene-knockdown calf using plasmid vectors harboring the U6 or tRNA promoter.

    Science.gov (United States)

    Wongsrikeao, Pimprapar; Sutou, Shizuyo; Kunishi, Miho; Dong, Ya Juan; Bai, Xuejin; Otoi, Takeshige

    2011-01-01

    By combining RNAi technology with SCNT method, we attempted to produce transgenic calves with knocked down bPRNP for technological assessments. The respective utilities of type II (tRNA) and type III (hU6) Pol III promoters in mediating plasmid vector-based RNAi for the production of a bPRNP-knockdown calf were compared. Plasmid harboring DNA for siRNA expression was introduced stably into the genome of primary cultured bovine cells. By inserting the transgenic cell into an enucleated bovine egg, SCNT embryos were produced. The ability for SCNT embryos to develop to blastocysts was higher in hU6 based vector groups (44-53%) than in a tRNA group (32%). In all, 30 hU6-embryos and 12 tRNA-embryos were transferred to 11 recipients. Only tRNA-embryos were able to impregnate recipients (6 out of 11 transfers), resulting in four aborted fetuses, one stillbirth, and one live-born calf. The expression of EGFP, a marker, was detected in all six. The bPRNP transcript levels in the nervous tissues (brain, cerebellum, spinal bulb, and spinal cord) from the calf, which was killed 20 days after birth, were reduced to 35% of those of the control calf on average, as determined by qRT-PCR. The PrPC levels, as estimated by western blot were reduced to 86% on average in the nervous tissues. These findings suggest that SCNT technology remains immature, that the tRNA promoter is useful, and that RNAi can significantly reduce PRNP mRNA levels, but insufficient reduction of PrPC levels exists in cattle under these conditions.

  7. Kunjin virus replicons: an RNA-based, non-cytopathic viral vector system for protein production, vaccine and gene therapy applications

    NARCIS (Netherlands)

    Pijlman, G.P.; Suhrbier, A.; Khromykh, A.A.

    2006-01-01

    The application of viral vectors for gene expression and delivery is rapidly evolving, with several entering clinical trials. However, a number of issues, including safety, gene expression levels, cell selectivity and antivector immunity, are driving the search for new vector systems. A number of re

  8. Construction of lentiviral vector of shRNA specific for rat PAX2 and the silencing effect%大鼠PAX2基因RNA干扰慢病毒载体的构建及沉默效果

    Institute of Scientific and Technical Information of China (English)

    李里; 吴玉斌

    2014-01-01

    Objective To observe the influence of lentiviral vector-mediated RNA interference on expression of rat PAX 2 gene in rat normal renal tubular epithelial cells (NRK52E).Methods The effective RNA interference sequence targeting PAX 2 gene was screened and determined according to previous study.The complementary DNA containing both sense and antisense Oligo DNA of the targeting sequence was designed,synthesized and cloned into pGCSIL-GFP vector to construct a lentiviral vector which expressed PAX 2 shRNA,subsequently confirmed by PCR and DNA sequencing analysis.293 T cells were co-transfected with the plasmids using liposome transfection methods ,and packaged to produce lentiviral particles.The recombinant lentiviruses were transfected into NRK52 E cells, and the PAX2 mRNA and protein expression were examined by RT-PCR and Western blot .The results were compared with those of the non-transfected and blank vector trans-fected NRK52E cells.Results PCR analysis and DNA sequencing confirmed that the PAX 2 shRNA sequences were successfully inserted in-to the lentiviral vectors.After transfection with PAX2 shRNA,the PAX2 expression in NRK52E cells was significantly inhibited at both mR-NA and protein levels compared with that in non-transfected and empty vector transfected NRK 52E cells.Conclusions The lentiviral RNAi vectors targeting PAX2 gene have been successfully constructed ,and can effectively inhibit the expression of PAX 2 gene in NRK52E cells.It paves a way for PAX2-targeted gene therapy of obstructive nephropathy.%目的:构建PAX2特异性shRNA 干扰慢病毒载体并观察其对大鼠肾小管上皮细胞( NRK52E)中PAX2基因的沉默效果。方法采用PAX2基因 RNAi靶点序列合成靶序列的 Oligo DNA,退火形成双链 DNA,与pGCSIL-GFP载体连接产生 shRNA慢病毒载体,经 PCR筛选阳性克隆进行 DNA 测序鉴定。用脂质体转染法将质粒共转染293T 细胞,将包装产生的慢病毒颗粒感染NRK52E

  9. Inhibition of HIV-1 in Vitro by Combination of Vpr and Tat Specific Short Hairpin RNA via Lentiviral Vectors%慢病毒介导双shRNA靶向于HIV的抑制作用研究

    Institute of Scientific and Technical Information of China (English)

    郝彦哲; 滕智平; 杨怡姝; 孙晓娜; 马晶; 金孝华; 曾毅

    2013-01-01

    RNA干扰可以有效地抑制特定基因的表达,在HIV基因治疗中成为一种重要的方法.为了防止病毒逃逸株的出现,本研究分别构建了靶向于HIV-1调控蛋白基因vpr和tat的shRNA重组慢病毒载体以及含有这两种shRNA的双表达重组慢病毒载体,分别由U6和H1两种启动子启动,通过与靶向基因tat和vpr表达质粒在293T细胞中进行共转染,采用荧光定量PCR方法测定细胞内靶向基因的表达丰度,结果显示双表达shRNA的重组慢病毒载体对vpr和tat的表达抑制率分别可以达到89.20%和62.00%.与pNL4-3病毒包装质粒共转染,P24ELISA显示plvx-vpr-tat shRNA对病毒包装产量的抑制率可以达到99.05%,比单个shRNA的抑制率都要强,HIV-1 NL4-3体外对MT4细胞攻毒实验表明双shRNA重组慢病毒载体具有很强的抑制病毒复制的能力.%Gene therapy offers the promise of curing the HIV-infected patients. Specific, potent, and sustained short hairpin RNA (shRNA)-mediated gene silencing is crucial for the successful application of RNA interference technology to therapeutic interventions. To reduce the probability of viral escape mutants, in this study, we constructed lentiviral vector containing vpr and tat shRNA, respectively, furthermore the bispecific lentiviral vector harboring vpr and tat shRNA expression cassettes from U6 pro-motor and H1 promotor was cotransfected with recombinant plasmid expressing the vpr and tat gene. The result showed that the bispecific lentiviral vector plvx-vpr-tatshRNA could inhibit the vpr and tat effectively, with ratios of 89. 20% and 62. 00% respectively. When cotransfected with pNL4-3 in 293T cell, plvx-vpr-tatshRNA showed higher efficacy in down regulating the HIV NL4-3 packaging production than the plvx-vprshRNA or plvx-tatshRNA individually. MT4 cell clones transduced with recombinant lentiviral vectors were screened and challenged with HIV NL4-3. P24 ELISA test showed that MT4 transduced with the

  10. Construction and identification of lentiviral vector of RNA interference of mouse Smad6 gene%小鼠Smad6基因RNAi慢病毒载体的构建与鉴定

    Institute of Scientific and Technical Information of China (English)

    刘铮; 代继宏; 符州; 冯琳琳

    2011-01-01

    构建小鼠Smad6基因RNA干扰(RNAi)慢病毒载体,有效沉默骨髓树突状细胞(BMDC)的Smad6基因表达,为构建骨髓致耐受DC用于哮喘等自身免疫疾病的研究.设计小鼠Smad6 shRNA序列,合成、退火,得到双链DNA,与经酶切后的Psih1-H1-copGFP shRNA Vector载体连接产生LV-shSmad6慢病毒载体,并测序鉴定.转染293TN细胞,包装产生慢病毒,测定滴度.感染小鼠骨髓树突细胞,检测Smad6基因的表达状况成功构建Smad6 shRNA的慢病毒载体LV-shSmad6.包装慢病毒,并显著抑制Smad6 mRNA水平及蛋白水平的表达.成功构建出小鼠Smad6基因shRNA慢病毒载体,为后期研究Smad6基因在哮喘发病机制及新治疗方法提供了稳定的转染细胞载体.%To construct a lentiviral vector of RNA interference ( RNAi) of mouse Smad6 gene and to effectively silence the Smad6 gene expression of bone marrow derived dendritic cells for construction the bone marrow tolerogenic dendritic cell for providing experimental foundation of athma of autoimmune disease, Smad6 shRNA sequence of mouse was designed by software. The complementary DNA containing both sence and antisence DNAs of the targeting sequence was designed, synthesized and cloned into the Psih1 -H1 -copGFP shRNA vector containing Smad6 shRNA named LV-shSmad6 which was confirmed sequencing. 293TN cells were cotransfected. PCR and DNA sequencing demonstrated that the lentivirus RNAi vector of Smad6 producing Smad6 shRNA was constructed successfully. Smad6 mRNA level and protein level express were kept down notability.

  11. About vectors

    CERN Document Server

    Hoffmann, Banesh

    1975-01-01

    From his unusual beginning in ""Defining a vector"" to his final comments on ""What then is a vector?"" author Banesh Hoffmann has written a book that is provocative and unconventional. In his emphasis on the unresolved issue of defining a vector, Hoffmann mixes pure and applied mathematics without using calculus. The result is a treatment that can serve as a supplement and corrective to textbooks, as well as collateral reading in all courses that deal with vectors. Major topics include vectors and the parallelogram law; algebraic notation and basic ideas; vector algebra; scalars and scalar p

  12. Vector analysis

    CERN Document Server

    Newell, Homer E

    2006-01-01

    When employed with skill and understanding, vector analysis can be a practical and powerful tool. This text develops the algebra and calculus of vectors in a manner useful to physicists and engineers. Numerous exercises (with answers) not only provide practice in manipulation but also help establish students' physical and geometric intuition in regard to vectors and vector concepts.Part I, the basic portion of the text, consists of a thorough treatment of vector algebra and the vector calculus. Part II presents the illustrative matter, demonstrating applications to kinematics, mechanics, and e

  13. Inhibition of cervical cancer cell growth in vitro and in vivo by lentiviral-vector mediated shRNA targeting the common promoter of HPV16 E6 and E7 oncogenes.

    Science.gov (United States)

    Zhou, Jiansong; Li, Baohua; Peng, Chanjuan; Wang, Fenfen; Fu, Zhiqin; Zhou, Caiyun; Hong, Die; Ye, Feng; Lü, Weiguo; Xie, Xing

    2013-05-01

    Deregulated expression of high-risk human papillomavirus oncogenes (E6 and E7) is a pivotal event for pathogenesis and progression in cervical cancer. Both viral oncogenes are therefore regarded as ideal therapeutic targets. Small interfering RNAs (siRNA) or double-stranded RNAs can knock down target genes effectively through siRNA-induced transcriptional gene silencing (TGS). Here, we established lentiviral-vector mediated shRNA (LV-shRNA) targeting common promoter of HPV16 E6/E7 and targeting E6 transcript, transduced the lentiviral construct into cervical HPV16-positive cell lines Siha and Caski, then selected and established stably transduced monoclonal cell lines. The results showed that LV-shRNA targeting promoter, as well as targeting E6 transcript, effectively knocked down E6 and E7 expression, resulted in accumulation of p53 and pRB protein and decrease of MCM7 and p16 protein, and consequently remarkably reduced the abilities of proliferation and invasiveness of cervical cancers cells in vitro. Then we inoculated subcutaneously those monoclonal cells into nude mice to establish the transplanted tumor animal models, and found dramatically inhibited tumorigenesis and growth, as well as prolonged survival time of mice incubated by cells with LV-shRNA targeting promoter and E6 transcript. Our results may provide evidence for application of LV-shRNA targeting HR-HPV key oncogenes, as a new treatment strategy, in cervical and other HPV-associated cancer therapy. Copyright © 2013 Elsevier B.V. All rights reserved.

  14. Construction of the AKT2 3′-UTR luciferase reporter gene vector and verification of the targeted relationship with miRNA-625%A KT23′-U TR荧光素酶报告基因载体构建及与miRNA-625靶向关系验证

    Institute of Scientific and Technical Information of China (English)

    魏斌; 邓霞; 卞秀娟; 钱粉红

    2016-01-01

    目的:通过构建荧光素酶报告基因重组质粒验证miRNA-625与AKT2基因的靶向调控关系。方法:通过生物信息学软件预测AKT2为miRNA-625靶基因;构建野生型AKT2基因3′端非翻译区荧光素酶报告基因载体及miR-NA-625靶序列突变型载体;将HEK-293T细胞株随机分为野生型+miRNA-625组、野生型+miRNA内参组、突变型+miRNA-625组、突变型+miRNA内参组;Lipofectamine 2000转染相应的质粒与miRNA,双荧光素酶报告基因系统检测荧光素酶活性。结果:构建野生型及突变型荧光素酶报告载体鉴定正确,双荧光素酶报告基因检测系统显示野生型+miRNA-625组相对荧光素酶活性较野生型+miRNA内参组明显降低(t=14.1764,P<0.05)。结论:miRNA-625对野生型AKT2重组质粒荧光活性有明显的抑制作用,证实miRNA-625能够靶向调控AKT2基因。%Objective:To identify the targeted-regulating relationship between miRNA-625 and AKT2 via constructing luciferase reporter gene vector.Methods:The AKT2 was predicted as miRNA-625 target gene by biological software.The 3′-untranslated regions(3′-UTR)of the wild type AKT2 and mutant AKT2 sequence were cloned into luciferase reporter vector pMIR-Report.The HEK-293T cells were divided into four groups randomly,wild-type plasmid +miRNA-625 group,wild-type plasmid +miRNA negative con-trol group,mutant plasmid +miRNA-625 group,mutant plasmid+miRNA negative control group.The rel-evant plasmids and miRNAs were transfected into groups by Lipofectamine 2000.The luciferase activity was detected by dual luciferase reporter gene system.Results:The recombinant plasmids were identified cor-rectly.Dual-luciferase reporter assay system revealed luciferase activity of wild-type plasmid+miRNA-625 group was significantly lower than that of wild-type plasmid+miRNA negative control group(P<0.05 ). Conclusion:The miRNA-625 inhibited the luciferase activity of AKT2 wild type

  15. TCF25干扰慢病毒载体的构建与鉴定%Construction and Characterization of a Lentiviral Vector for RNA Interference of TCF25

    Institute of Scientific and Technical Information of China (English)

    李佑锋; 彭浩; 高建芳; 高晶; 陈宇; 吴秀山; 李永青

    2016-01-01

    为构建一个针对TCF25(transcription factor 25)基因的慢病毒干扰载体,设计并合成3组针对TCF25的短发夹RNA序列(shRNA),通过基因重组技术连入pLL3.7载体,酶切鉴定及DNA测序后,重组正确的pLL3.7质粒与病毒包装质粒共转染293FT细胞,培养48 h后,分别收集细胞培养上清液,感染H9C2细胞,Western-blot检测TCF25在H9C2细胞中的表达.结果显示TCF25蛋白在H9C2细胞中的表达被抑制.这说明TCF25的慢病毒干扰载体构建成功.%Objective To construct a lentiviral vector for RNA interference of TCF25 (transcription factor 25)gene and identify it.Methods Three pairs of complementary short hairpin RNA (shRNA)oligonucleotides targeting the TCF25 gene were designed,synthesized,and then inserted into pLL3.7 vectors by gene recombination technology.The recombinant plasmid was identified by enzyme digestion and DNA sequencing.Correct recombi-nant plasmids were cotransfected with packaging plasmids into 293FT cells.The cell culture supernatant was ob-tained after 48 hours,and then applied to infect H9C2 cells.The expression of TCF25 in H9C2 cells was detected by western-blot.Results The recombinant plasmid was successfully constructed.The western-blot showed that the expression of TCF25 in H9C2 cells was inhibited after the cells were successfully infected with the lentiviral vector supernatant.Conclusion The lentiviral vector interfering TCF25 was constructed successfully.

  16. DNMT3B mRNA 3′untranslation region report vector construction and the relationship to atherosclerosis%DNMT3B mRNA 3′非编码区报告基因载体的构建与功能验证

    Institute of Scientific and Technical Information of China (English)

    曹成建; 杨晓玲; 王磊; 杨程; 蔡欣; 徐华; 王洁; 姜怡邓

    2014-01-01

    目的:构建用于鉴定microRNA(miRNA)靶基因的报告基因系统并进行功能验证,为研究动脉粥样硬化的发生发展机制奠定良好基础。方法在pGL3-control载体的荧光素酶基因下游克隆位点插入DNA甲基转移酶3B(DNMT3B)3′非编码区序列,经酶切、测序验证是否插入及正确性。生物信息学分析 DNMT3B与 miRNA-125b的靶向关系,并用 miRNA-125b过表达载体与所构建载体共转染人血管平滑肌细胞,双荧光素酶报告基因系统检测荧光素酶活性。结果成功构建了DNMT3 B 3′非编码区报告基因载体,经酶切和测序鉴定正确;共转染细胞24 h后,双荧光素酶报告基因系统检测荧光素酶活性,结果显示与空载体对照组相比,构建载体组荧光素酶活性下降了54.8%(P<0.01)。结论成功构建了DNMT3B mRNA 3′非编码区报告基因载体,且提示miRNA-125b靶向调控了DNMT3B。%Objective To construct a reporter gene system for the identification of microRNA target genes and verify its func-tion,and lays a good foundation for studying the mechanisms of the occurrence and development of atherosclerosis.Methods Put-ting the DNA methyltransferase 3B(DNMT3B)3′untranslation region into the cloning site downstream of the luciferase gene of the pGL3-Control vector,and the correctness was validated by restriction enzyme digestion and sequencing.The bioinformatics was used to analysis the relationship between DNMT3B and miRNA-125b and the miRNA-125b overexpression vector were co-transfected with the constructed vectors into the human vascular smooth muscle cells,and the luciferase activity was detected by dual luciferase reporter assay system.Results The DNMT3B 3′untranslation region reporter vector was built successfully,and the correctness was verified by the restriction enzyme digestion and sequencing;after co-transfected 24 h,compared with the empty vector control group,the luciferase activity

  17. Elementary vectors

    CERN Document Server

    Wolstenholme, E Œ

    1978-01-01

    Elementary Vectors, Third Edition serves as an introductory course in vector analysis and is intended to present the theoretical and application aspects of vectors. The book covers topics that rigorously explain and provide definitions, principles, equations, and methods in vector analysis. Applications of vector methods to simple kinematical and dynamical problems; central forces and orbits; and solutions to geometrical problems are discussed as well. This edition of the text also provides an appendix, intended for students, which the author hopes to bridge the gap between theory and appl

  18. Molecular interactions and immune responses between maize fine streak virus and the leafhopper vector G. nigrifrons through differential expression and RNA interference

    Science.gov (United States)

    Maize fine streak virus (MFSV) is an emerging virus of maize that is transmitted by an insect vector, the leafhopper called Graminella nigrifrons. Virus transmission by the leafhopper requires that the virus enter into and multiply in insect cells, tissues and organs before being transmitted to a ne...

  19. Carbohydrate-interactive pDNA and siRNA gene vectors based on boronic acid functionalized poly(amido amine)s

    NARCIS (Netherlands)

    Piest, Martin; Ankone, Martinus J.K.; Engbersen, Johannes F.J.

    2013-01-01

    In order to evaluate the influence of incorporation of boronic acid groups on the properties of poly(amido amine)s as gene vectors, a novel poly(amido amine) copolymer p(CBA-ABOL/2AMPBA) containing ortho-aminomethylphenylboronic acid (2AMPBA) moieties was prepared by Michael-type polyaddition of a m

  20. Construction of a short hairpin RNA interference lentiviral vector of SIRT1 gene and detection of interference effect%SIRT1基因shRNA慢病毒载体构建及干扰效应检测

    Institute of Scientific and Technical Information of China (English)

    邓昭玲; 王彦; 杜利清; 刘强; 赵辉; 陈乃耀

    2012-01-01

    BACKGROUND: SIRT1 gene plays a very important role in cell energy metabolism, apoptosis and ageing, while other studies have found that SIRT1 may play a regulatory role in the inflammatory response. OBJECTIVE: To construct short hairpin RNA interference lentiviral vector of SIRT1 gene and to evaluate their inhibitory effect in THP-1 cells. METHODS: The SIRI1 target specific oligonucleotide sequence was designed, synthesized and connected into the pGCSIL-GFP vector digested by Age I and EcoR I 293T cells were packaged to produce the lentivirus, and then transfected with THP-1 cells. The inhibitory effect on SIRT1 gene was tested by the real-time quantitative PCR and Western Blot. RESULTS AND CONCLUSION: The PCR and DNA sequencing of positive clones demonstrated that the lentivirus shRNA vector of SIRT1 gene was constructed successfully. The real-time quantitative PCR and Western Blot confirmed that the vector could suppress the expression level of SIRT1 at mRNA and protein levels.%背景:SIRT1基因在细胞能量代谢、凋亡及衰老过程中发挥极重要的作用,另有研究发现SIRT1可能在炎症反应方面起着调控作用.目的:构建SIRT1特异性的shRNA慢病毒载体,并初步检测其对THP-1细胞SIRT1基因的抑制效应.方法:设计SIRT1靶点特异性的寡核苷酸序列,连接到经Age Ⅰ和EcoR Ⅰ酶切线性化的pGCSIL-GFP载体,包装293T细胞产生慢病毒,再转染THP-1细胞,通过实时荧光定量PCR实验及Western Blot检测对SIRT1靶基因的抑制情况.结果与结论:阳性克隆PCR及测序证实SIRT1基因shRNA慢病毒载体构建成功,实时荧光定量PCR及Western Blot检测该载体在mRNA和蛋白水平能抑制THP-1细胞的SIRT1表达.

  1. Construction of Bcl-2 Antisense RNA Expressed by Defect Retroviral Vector%反义bcl-2基因逆转录病毒表达载体的构建

    Institute of Scientific and Technical Information of China (English)

    林祥华; 陈志哲; 杨婷; 吕联煌

    2001-01-01

    目的克隆bcl-2基因,构建其不同反义核酸的逆转录病毒表达载体。方法设计一对两端带有EcoRⅠ酶切位点的引物,RT-PCR克隆含bcl-2全部编码区的848 bp片段,并连接到T载体,测序正确后正反向亚克隆到pLXSN中EcoRⅠ位点;从pBluescriptⅡSK(-)bcl-2中用BamHⅠ切下含有bcl-2阅读框起始部位的部分编码区亚克隆到pLXSN BamHⅠ位点。结果构建带有正反向含bcl-2阅读框的全部编码区和部分编码区的逆转录病毒表达载体。结论在已知基因序列克隆中,联合RT-PCR和T载体是一个简单、快速、有效的方法,为基因转移和表达研究提供基础。%Objective To clone bcl-2 gene and develop two different bcl-2 antisense RNA expressed by defect retroviral vector. Methods Both upper and down primers with the end of EcoRⅠ site were designed to amplify 848 bp cDNA fragement including the whole bcl-2 exon by RT-PCR. After confirmation of the sequences of cloned bcl-2 exon by T vector, both forward and backward of bcl-2 cDNA were subcloned into the EcoRⅠ site of retroviral vector pLXSN. In the other way, 600 bp cDNA fragement with the beginning of coding bcl-2 exon was obtained by digestion of pBluescriptⅡ SK(-) bcl-2 with BamHⅠ restriction enzyme and also subcloned into the BamHⅠ site of retroviral vector pLXSN. Results Retroviral vectors with both forward and backward, whole and part of bcl-2 exon were successfully constructed. Conclusion Under the knowledge of targeting cDNA sequences, the approach for clonning of targeting gene by combination of RT-PCR with T vector is simple, rapid, effective, and offering the underlying bases of gene transfer and expression.

  2. The interference effects on UL29 shRNA expression vectors on HSV-2%单纯疱疹Ⅱ型病毒UL29基因shRNA表达载体的干扰效应

    Institute of Scientific and Technical Information of China (English)

    黄畅; 潘晓瑜; 袁俊杰; 吕延成

    2014-01-01

    目的:应用RNA干扰技术,针对单纯疱疹Ⅱ型病毒(HSV-2)UL29基因构建短发夹RNA重组表达载体,观察其对HSV-2的干扰效应。方法:针对HSV-2 UL29基因筛选出4条拟干扰靶位点序列,分别设计、合成4组靶向UL29基因shRNA的基因真核表达载体。通过脂质体转染到HEK293细胞。再将HSV-2接种到HEK293细胞中。采用终点滴定法检测病毒滴度,RT-PCR检测shRNA对转录水平的影响,Western-blot检测shRNA对蛋白质表达水平的影响。结果:终点滴定法结果显示UL29shRNA各组均可不同程度降低病毒感染滴度,与空白组(未转染重组表达载体)比较差异显著(P<0.01)。RT-PCR结果显示,与空白组比较,4组抑制率分别为28.80%、59.95%、66.08%、36.27%,差异均具有显著性(P<0.05),shRNANC(不针对任何基因的序列)与空白组相比差异无显著性,其中以UL29shRNA1461组效果为最佳。 Western-blot检测表明UL29shRNA各组ICP8蛋白表达水平比阴性对照组明显降低。结论:UL29shRNA能有效干扰HSV-2UL29基因的表达,抑制HSV-2在HEK293细胞中的复制。%Objective To construct short hairpin RNA (shRNA) recombinant expression vector for herpes simplex virus typeⅡ(HSV-2) UL29 gene and observe its inhibitory effect on HSV-2. Methods Four interference target sites of HSV-2UL29 gene were selected to construct 4 groups of small hairpin RNA respectively,named shRNA recombinant expression vector. The expression vectors were transfected into HEK293 cells with liposome. HEK293 cells were infected with HSV-2 after expression vector being transfected. The viral titer was estimated by end-point titration assay. The level of transcription was estimated by Real-Time PCR method. The expressing effect of protein was detected by Western-blot. Results Recombinant expression vector pGPU6/GFP/Neo-shRNA was constructed successfully. The result of end-point titration assay

  3. Vector analysis

    CERN Document Server

    Brand, Louis

    2006-01-01

    The use of vectors not only simplifies treatments of differential geometry, mechanics, hydrodynamics, and electrodynamics, but also makes mathematical and physical concepts more tangible and easy to grasp. This text for undergraduates was designed as a short introductory course to give students the tools of vector algebra and calculus, as well as a brief glimpse into these subjects' manifold applications. The applications are developed to the extent that the uses of the potential function, both scalar and vector, are fully illustrated. Moreover, the basic postulates of vector analysis are brou

  4. 小鼠 IL-35基因 shRNA 慢病毒载体构建与RNAi 效率的鉴定%Construction of shRNA Lentiviral Vector Targeting Mice IL-35 Gene and Identification of RNAi Efficiency

    Institute of Scientific and Technical Information of China (English)

    刘义帅; 王洪伟; 邸大琳; 付晓燕; 吴国庆; 王丽娜; 鞠吉雨

    2014-01-01

    目的:构建小鼠IL-35基因靶向shRNA干扰的慢病毒表达载体,抑制小鼠肝癌细胞Hepa1~6中IL-35的表达。方法设计合成IL-35EBI3亚基基因靶向shRNA序列,构建shRNA载体PLKO.1-IL-35 EBI3 shRNA-GFP,测序正确后,三质粒病毒包装系统(质粒载体+psPAX2+pMD2.G)包装成表达干扰IL-35 EBI3 shR-NA的慢病毒,慢病毒感染靶细胞Hepa1~6,荧光显微镜下观察感染效率,以实时定量RT-PCR分析对Hepa1~6细胞IL-35 EBI3基因表达的干扰效果。结果测序证实,成功构建了真核表达干扰载体PLKO.1-IL-35 EBI3 shRNA-GFP;并成功包装出表达干扰IL-35 EBI3 shRNA的慢病毒,以MOI值4.6pfu/细胞感染Hepa1~6细胞,镜下显示感染效率约90%;RT-PCR结果表明所构建的3个慢病毒载体PLKO.1-IL-35 EBI3 shRNA-GFP均可以有效干扰IL-35 EBI3的表达,其中E545干扰效率最高,为64%.结论成功构建IL-35EBI3亚基基因的shRNA慢病毒表达载体,该慢病毒表达载体能够在细胞水平有效沉默靶基因。%Objective To construct the shRNA lentiviral vectors targeting mice IL-35 gene and detect its effect of gene silence in Hepa1~6 cells.Methods The specific siRNA sequences targeting mice IL-35 gene were designed and cloned into eukaryotic expression vector PLKO.1-IL-35 EBI3 shRNA-GFP.After the correct sequencing identification ,the lentivirus particles targeting mice IL-35 gene were packaged with the three plasmid virus packaging system .The IL-35 gene specific shRNAs were infected into Hepa1~6 cells.Then,infection efficiency were observed by the fluorescence microscope .Real time reverse transcription PCR was performed to determine the expression level of IL-35 EBI3 mRNA.Results Sequencing results revealed that PLKO .1-IL-35 EBI3 shRNA-GFP plasmids were correctly constructed .The lentivirus particles targeting mice IL-35 gene were packaged successfully .The observed infection efficiency by the fluorescence

  5. Construction of a siRNA vector targeting Smad3 gene and gene-silencing effect%Smad3基因siRNA表达载体的构建及沉默效应

    Institute of Scientific and Technical Information of China (English)

    王爱丽; 吴志宏; 徐顺; 顾耀辉; 黄静; 陈波; 贾卿

    2011-01-01

    BACKGROUND: Previous studies demonstrated that inhibition of Smad3 can suppress fibroplasias or collagen over expression.OBJECTIVE: To construct an expression vector of siRNA targeting human Smad3 gene and observe its gene-silencing effect in hypertrophic scar (HS) fibroblasts METHODS: The siRNA sequences targeting Smad3 gene were designed and synthesized with two complementary oligonucleotide strands. The oligonucleotide strands were annealed and recombined into pRNAT-U6 vector, which was identified by sequencing following transformation and amplification. The siRNA expression vector pRNAT -U6- Smad3 was transfected into human HS fibroblasts. Smad3 expressions in mRNA and protein levels were examined by real-time-PCR and Western blotting.RESULTS AND CONCLUSION: The result of recombinant sequence was the same as aim sequence. Real-time RCR and Western blot showed that, compared to blank, the mRNA and protein levels of Smad3 were significantly decreased. Thereinto,the most effective siRNA sequence was AGA CAG ACT GTG ACC AGT A (1156). The gene-silent efficiency was 45%.Smad3-siRNA recombinant was constructed successfully and can be transfected into HS fibroblasts to inhibit the expression of Smad3 gene.%背景:研究提示抑制Smad3可望抑制纤维增生和胶原的大量产生.目的:构建针对Smad3基因的siRNA表达载体,观察RNA干扰对增生性瘢痕成纤维细胞Smad3基因表达的抑制作用.方法:根据siRNA设计原则,设计3条针对Smad3基因的siRNA靶序列,分别合成两条互补的寡核苷酸链,退火后与载体pRNAT-U6连接,然后进行酶切鉴定和DNA序列测定.用脂质体包裹转染增生性瘢痕成纤维细胞,荧光定量PCR和Western blot方法检测Smad3基因的表达情况.结果与结论:测序分析结果显示:克隆入pRNAT-U6载体的针对Smad3基因的siRNA的双链寡核苷酸片段插入正确;荧光定量PCR和Western blot检测显示:转染的增生性瘢痕成纤维细胞Smad3基因的表

  6. Construction and Identification of Expression Vector of siRNA Specific for Alpha-Fetoprotein%甲胎蛋白特异性小干扰RNA表达载体的构建及鉴定

    Institute of Scientific and Technical Information of China (English)

    郏雁飞; 胡安拉; 汪运山; 周芳; 马晓丽; 苏占涛

    2007-01-01

    目的:构建特异性抑制甲胎蛋白(AFP)的小干扰RNA(siRNA)表达载体,为进一步研究AFP基因功能及AFP相关肿瘤的基因治疗奠定基础.方法:设计并合成AFP特异性的短链寡核苷酸,退火形成双链DNA片段,通过与RNAi-ReadypSIREN-DNR-DsRed-Express Donor Vector连接、转化大肠杆菌、扩增、纯化得到所需质粒,用琼脂糖凝胶电泳及基因测序鉴定其分子量及插入片段的序列.结果:琼脂糖凝胶电泳证实纯化后的质粒大小约为6 740 bp,测序证实插入序列与合成的寡核苷酸序列完全符合.结论:构建了AFP特异性的siRNA表达质粒pSIREN-DNR-DsRed-Express Donor Vector-AFP.

  7. 大鼠野生型TRAF6基因和TRAF6shRNA表达质粒的构建及鉴定%Construction and identification of TRAF6 gene and its shRNA expression vector

    Institute of Scientific and Technical Information of China (English)

    邱文; 单锴; 庞蓉蓉; 季明德; 王迎伟

    2011-01-01

    Objective: To construct tumor necrosis factor receptor-associated factor 6 (TRAF6) and its small hair RNA (shRNA) expression vectors, and to assess their function on rat glomerular mesangial cell (CMC). Methods: The full-length TRAF6 CDS (HA tag) or three kinds of shRNAs targeting TRAF6 gene were synthesized and cloned into eukaryotic expression plasmid pcDNA3.1 and pGenesil-1/GFP,respectively. After confirmed by restriction endonuclease digestion and nucleotide sequencing,the recombinant plasmids were transfected into cultured rat GMC through Neon? Transfection system. Western blot assay was then used to confirm the expression of HA-TRAF6 and find out the optimal shRNA against TRAF6 gene. Results; It was verified by restriction endonuclease digestion and nucleotide sequencing that the constructed eukaryotic vectors were all correct. Western blot assay showed that the plasmids of pcDNA3.1-HA-TRAF6 could express HA-TRAF6 and the TRAF6 shRNA-1 (shTRAF6-l) was able to silence the target gene effectively. Conclusion; The expression plasmid of TRAF6 gene and its shRNA were constructed successfully, which provides essential experimental tools for studying biological functions of TRAF6 gene in the future.%目的:构建大鼠野生型肿瘤坏死因子受体相关因子6 (tumor necrosis factor receptor-associated factor 6,TRAF6)基因及其特异性短发卡状小干涉RNA (shRNA)真核表达质粒,并观察其在大鼠肾小球系膜细胞(GMC)中过表达和沉默TRAF6基因的情况.方法:用DNA重组技术将针对大鼠TRAF6基因的CDS区序列(加HA标签)和针对其不同位点所设计的3种shRNA序列分别克隆到pcDNA3.1及pGenesil- 1/GFP真核表达质粒中.在酶切鉴定及序列测定正确后,用NeonTM电转仪,将上述质粒分别转染入培养的大鼠GMC中,然后用Western blot检查HA-TRAF6融合蛋白的表达情况,同时筛选最有效的TRAF6shRNA.结果:限制性酶切及核酸序列分析确证,上述TRAF6基因过表达和shRNA

  8. Therapeutic and prophylactic applications of alphavirus vectors.

    Science.gov (United States)

    Atkins, Gregory J; Fleeton, Marina N; Sheahan, Brian J

    2008-11-11

    Alphavirus vectors are high-level, transient expression vectors for therapeutic and prophylactic use. These positive-stranded RNA vectors, derived from Semliki Forest virus, Sindbis virus and Venezuelan equine encephalitis virus, multiply and are expressed in the cytoplasm of most vertebrate cells, including human cells. Part of the genome encoding the structural protein genes, which is amplified during a normal infection, is replaced by a transgene. Three types of vector have been developed: virus-like particles, layered DNA-RNA vectors and replication-competent vectors. Virus-like particles contain replicon RNA that is defective since it contains a cloned gene in place of the structural protein genes, and thus are able to undergo only one cycle of expression. They are produced by transfection of vector RNA, and helper RNAs encoding the structural proteins. Layered DNA-RNA vectors express the Semliki Forest virus replicon from a cDNA copy via a cytomegalovirus promoter. Replication-competent vectors contain a transgene in addition to the structural protein genes. Alphavirus vectors are used for three main applications: vaccine construction, therapy of central nervous system disease, and cancer therapy.

  9. Research Area 14.3 Microbiology and Biodegradation: Development of RNA-based Vectors for in vivo Delivery of siRNAs

    Science.gov (United States)

    2014-09-08

    Viruses and Uses Thereof 5a: 5f-1a: 5f-c: 7 1     Title:  Final  Report:  Research  Area  14.3   Microbiology  and...tenOever.   Molecular   risk   mitigation   of   gain-­‐of-­‐ function  studies  with   influenza   viruses .  Nature  Biotechnology...like  vectors  (VLVs)  for  the  production  of  small  RNAs.    We   show  that  

  10. Interfering Satellite RNAs of Bamboo mosaic virus

    Directory of Open Access Journals (Sweden)

    Kuan-Yu Lin

    2017-05-01

    Full Text Available Satellite RNAs (satRNAs are sub-viral agents that may interact with their cognate helper virus (HV and host plant synergistically and/or antagonistically. SatRNAs totally depend on the HV for replication, so satRNAs and HV usually evolve similar secondary or tertiary RNA structures that are recognized by a replication complex, although satRNAs and HV do not share an appreciable sequence homology. The satRNAs of Bamboo mosaic virus (satBaMV, the only satRNAs of the genus Potexvirus, have become one of the models of how satRNAs can modulate HV replication and virus-induced symptoms. In this review, we summarize the molecular mechanisms underlying the interaction of interfering satBaMV and BaMV. Like other satRNAs, satBaMV mimics the secondary structures of 5′- and 3′-untranslated regions (UTRs of BaMV as a molecular pretender. However, a conserved apical hairpin stem loop (AHSL in the 5′-UTR of satBaMV was found as the key determinant for downregulating BaMV replication. In particular, two unique nucleotides (C60 and C83 in the AHSL of satBaMVs determine the satBaMV interference ability by competing for the replication machinery. Thus, transgenic plants expressing interfering satBaMV could confer resistance to BaMV, and interfering satBaMV could be used as biological-control agent. Unlike two major anti-viral mechanisms, RNA silencing and salicylic acid-mediated immunity, our findings in plants by in vivo competition assay and RNA deep sequencing suggested replication competition is involved in this transgenic satBaMV-mediated BaMV interference. We propose how a single nucleotide of satBaMV can make a great change in BaMV pathogenicity and the underlying mechanism.

  11. The effect of lentiviral vector-mediated RNA interference targeting hypoxia-inducible factor 1α on the uptake of fluorodeoxyglucose ((18)f) in the human pancreatic cancer cell line, patu8988.

    Science.gov (United States)

    Fan, Guanglei; Bo, Jingli; Wan, Renming; Peng, Mingya; Luan, Yufen; Deng, Minbin; Xu, Longbao

    2015-05-01

    Hypoxia can stimulate (18)F-fluorodeoxyglucose ((18)F-FDG) uptake in cultured tumor cells. This study has investigated the effect of lentiviral vector-mediated RNA interference (RNAi) targeting hypoxia-inducible factor 1α (HIF-1α) on the changes in HIF-1 and glucose transporter 1 (Glut-1) expression, the cell growth, and the uptake of (18)F-FDG in the human pancreatic cancer cell line, Patu8988. Lentiviral RNAi vector targeting the HIF-1α gene (LV-HIF-1αRNAi) was constructed and used to treat cells at various concentrations (25-200 nM). The expression changes of HIF-1α and Glut-1 in hypoxic Patu8988 cells after RNAi treatment were determined using real time reverse transcription-polymerase chain reaction (real-time PCR). The inhibition rate of cell proliferation 48 hours after the addition of 10 μL of different concentrations of LV-HIF-1αRNAi (25-200 nM) was assayed using the MTT method. Meanwhile, the cell uptake of (18)F-FDG was also assessed. After RNAi transfection, the relative expression levels of HIF-1α mRNA and Glut-1 under hypoxia were reduced and the relative expression levels of HIF-1α protein also decreased. Compared with the control group, the inhibition rates of cell proliferation under different viral dosages were 5.98%, 15.65%, 26.42%, and 40.81%, respectively, positively correlated with the viral doses (r=0.558, p<0.05). Under hypoxia, Glut-1 mRNA expression in Patu8988 cells treated with 200 nM of LV-HIF-1αRNAi for 24, 48, and 72 hours, respectively, was positively correlated with the inhibition rate of cell proliferation (r=0.618, p<0.05) as well as the inhibition rate of (18)F-FDG uptake (r=0.664, p<0.05), while the latter two displayed a positive correlation with each other too (r=0.582, p<0.05). Under hypoxia, RNAi targeting HIF-1α significantly inhibited the expression of Glut-1 mRNA in Patu8988 pancreatic cancer cells and their uptake of (18)F-FDG. These results suggest that LV-HIF-1αRNAi may form a new treatment for

  12. Bunyavirus-vector interactions.

    Science.gov (United States)

    Beaty, B J; Bishop, D H

    1988-06-01

    Recent advances in the genetics and molecular biology of bunyaviruses have been applied to understanding bunyavirus-vector interactions. Such approaches have revealed which virus gene and gene products are important in establishing infections in vectors and in transmission of viruses. However, much more information is required to understand the molecular mechanisms of persistent infections of vectors which are lifelong but apparently exert no untoward effect. In fact, it seems remarkable that LAC viral antigen can be detected in almost every cell in an ovarian follicle, yet no untoward effect on fecundity and no teratology is seen. Similarly the lifelong infection of the vector would seem to provide ample opportunity for bunyavirus evolution by genetic drift and, under the appropriate circumstances, by segment reassortment. The potential for bunyavirus evolution by segment reassortment in vectors certainly exists. For example the Group C viruses in a small forest in Brazil seem to constitute a gene pool, with the 6 viruses related alternately by HI/NT and CF reactions, which assay respectively M RNA and S RNA gene products (Casals and Whitman, 1960; Shope and Causey, 1962). Direct evidence for naturally occurring reassortant bunyaviruses has also been obtained. Oligonucleotide fingerprint analyses of field isolates of LAC virus and members of the Patois serogroup of bunyaviruses have demonstrated that reassortment does occur in nature (El Said et al., 1979; Klimas et al., 1981; Ushijima et al., 1981). Determination of the genotypic frequencies of viruses selected by the biological interactions of viruses and vectors after dual infection and segment reassortment is an important issue. Should a virus result that efficiently interacts with alternate vector species, the virus could be expressed in different circumstances with serious epidemiologic consequences. Dual infection of vectors with different viruses is not unlikely, because many bunyaviruses are sympatric in

  13. A MicroRNA-regulated and GP64-pseudotyped Lentiviral Vector Mediates Stable Expression of FVIII in a Murine Model of Hemophilia A

    Science.gov (United States)

    Matsui, Hideto; Hegadorn, Carol; Ozelo, Margareth; Burnett, Erin; Tuttle, Angie; Labelle, Andrea; McCray, Paul B; Naldini, Luigi; Brown, Brian; Hough, Christine; Lillicrap, David

    2011-01-01

    The objective to use gene therapy to provide sustained, therapeutic levels of factor VIII (FVIII) for hemophilia A is compromised by the emergence of inhibitory antibodies that prevent FVIII from performing its essential function as a cofactor for factor IX (FIX). FVIII appears to be more immunogenic than FIX and an immune response is associated more frequently with FVIII than FIX gene therapy strategies. We have evaluated a modified lentiviral delivery strategy that facilitates liver-restricted transgene expression and prevents off-target expression in hematopoietic cells by incorporating microRNA (miRNA) target sequences. In contrast to outcomes using this strategy to deliver FIX, this modified delivery strategy was in and of itself insufficient to prevent an anti-FVIII immune response in treated hemophilia A mice. However, pseudotyping the lentivirus with the GP64 envelope glycoprotein, in conjunction with a liver-restricted promoter and a miRNA-regulated FVIII transgene resulted in sustained, therapeutic levels of FVIII. These modifications to the lentiviral delivery system effectively restricted FVIII transgene expression to the liver. Plasma levels of FVIII could be increased to around 9% that of normal levels when macrophages were depleted prior to treating the hemophilia A mice with the modified lentiviral FVIII delivery system. PMID:21285959

  14. 人Notch-1基因RNA干扰慢病毒载体的构建及鉴定%Construction and identification of a lentiviral vector of RNA interference containing human Notch-1 gene

    Institute of Scientific and Technical Information of China (English)

    张庆庆; 张森林; 朱迎兰; 董震; 曹罡; 陈伟

    2014-01-01

    目的:构建及鉴定人Notch-1基因的RNA干扰(RNAi)慢病毒载体,寻找最佳RNAi慢病毒载体。方法针对人Notch-1基因序列,按照RNAi序列设计原则,设计3段RNAi靶点序列(shRNA1~3),通过限制性内切酶BamHⅠ和EcoRⅠ双酶切、T4DNA连接酶连接,将Notch-1基因序列插入慢病毒载体pLenOR-THM,构建pLenOR-THM-Notch-1重组载体。质粒转化感受态DH5α细菌,筛选阳性克隆,经KpnⅠ和EcoRⅠ双酶切及测序鉴定正确后通过脂质体将慢病毒四质粒系统共转染293T细胞,进行慢病毒包装并测定病毒滴度,观察感染效率。各组病毒载体转染ACC-M细胞后,运用定量逆转录聚合酶链反应和Westernblot检测Notch-1基因mRNA和蛋白的表达水平。结果成功构建慢病毒载体pLenOR-THM-Notch-1,四质粒共转染293T细胞后可见大量绿色荧光;浓缩后的病毒滴度为5.8×108TU·mL-1;以复感染系数为1时感染293T细胞,感染效率在90%以上。QRT-PCR和Westernblot检测结果表明,pLenOR-Notch-1-shRNA3组受抑制程度最高。结论成功构建了人Notch-1RNAi慢病毒载体。%Objective To construct and identify a lentiviral vector of RNA interference targeting human Notch-1 gene. Methods To determine the Notch-1 gene sequences, three RNAi target sequences (shRNA1-3) were designed in accordance with the RNAi sequence design principles and cloned into the lentiviral vector pLenOR-THM by endonuclease BamHⅠres-triction, EcoRⅠdouble digestion, and T4 DNA-ligase ligation. After the transformation into competent DH5αbacteria, the candidate clones were identified by KpnⅠand EcoRⅠdouble digestion and DNA sequencing. The recombinant and three packaging plasmids were co-transfected into human embryonic kidney cell line 293T cells by lipofectamine to produce the lentiviral particles. The viral titer was determined. The 293T cells were infected by the lentiviral particles obtained, and trans-fection efficiency

  15. Cloning vector

    Science.gov (United States)

    Guilfoyle, R.A.; Smith, L.M.

    1994-12-27

    A vector comprising a filamentous phage sequence containing a first copy of filamentous phage gene X and other sequences necessary for the phage to propagate is disclosed. The vector also contains a second copy of filamentous phage gene X downstream from a promoter capable of promoting transcription in a bacterial host. In a preferred form of the present invention, the filamentous phage is M13 and the vector additionally includes a restriction endonuclease site located in such a manner as to substantially inactivate the second gene X when a DNA sequence is inserted into the restriction site. 2 figures.

  16. Cloning vector

    Science.gov (United States)

    Guilfoyle, Richard A.; Smith, Lloyd M.

    1994-01-01

    A vector comprising a filamentous phage sequence containing a first copy of filamentous phage gene X and other sequences necessary for the phage to propagate is disclosed. The vector also contains a second copy of filamentous phage gene X downstream from a promoter capable of promoting transcription in a bacterial host. In a preferred form of the present invention, the filamentous phage is M13 and the vector additionally includes a restriction endonuclease site located in such a manner as to substantially inactivate the second gene X when a DNA sequence is inserted into the restriction site.

  17. Alphavirus vectors for cancer gene therapy (review).

    Science.gov (United States)

    Yamanaka, Ryuya

    2004-04-01

    Alphaviruses have several characteristics that make them attractive as gene therapy vectors such as transient and high-level expression of a heterologous gene. Alphavirus vectors, Semliki Forest virus (SFV), Sindbis virus (SIN) and Venezuelan equine encephalitis virus (VEE) have been developed as gene expression vectors. Alphaviruses are positive-strand RNA viruses that can mediate efficient cytoplasmic gene expression in mammalian cells. The alphavirus RNA replication machinery has been engineered for high level heterologous gene expression. Since an RNA virus vector cannot integrate into chromosomal DNA, concerns about cell transformation are reduced. Alphavirus vectors demonstrate promise for the safe tumor-killing and tumor-specific immune responses. Recombinant alphavirus RNA replicons may facilitate gene therapy of cancer.

  18. Construction and Identification of Doxycycline-inducible shRNA Expressing Vector Targeting Porcine Nanog%猪Nanog基因四环素诱导干扰载体的构建和鉴定

    Institute of Scientific and Technical Information of China (English)

    张力; 罗一博; 牟彦双; 朱江; 李慧; 刘忠华

    2011-01-01

    , including inducible RNA polymerase Ⅲ ( polⅢ) promoters with embedded tetracycline operators (tetO) and co-expression of the tetracycline regulatory protein, TetR. In the absence of tetracycline or its derivative doxycycline, TetR homodimer binds tightly to the Tet operon ( s ) inserted within the promoter and acts to suppress transcription. Upon its addition, tetracycline binds with high affinity to the Tet repressor homodimer and causes a conformational change in the repressor that renders it unable to bind to tetO, allowing expression of the shRNA transcript. However, the process for generate stable cell line whose target gene knock-down is time-consuming multi-step process which limited transgenic animals' expansion. In addition, most shRNA expression units rely on polⅢ promoters such as the H1 or U6 promoter, but it is better to use RNA polymerase Ⅱ ( pol Ⅱ) promoters for tissue specific gene silencing. To overcome the limitation of shRNA expression systems in mammalian cells, a single vector which only incorporates tetO-hUbc promoter, tTS was used in this study. Firstly, five pGenesill. 0-shRNA plasmids were constructed and selected for the most effective shRNA target on porcine Nanog by Realtirae-PCR. In order to generate a single-vector harboring pol HI promoter allowing for rapid generation of stable cell lines for regulatable shRNA expression targets on porcine Nanog, the selected effective shRNA whose interference efficiency could reach 80% was inserted to a modified doxycycline-induced gene silencing vector TREsilencer. Realtime-PCR analysis demonstrates that efficiency of Nanog silencing could reach about 70% , with increasing concentration of doxycyline. It is a fundamental work for generating Nanog stably silenced porcine cell lines and further studying on Nanog genes* function.

  19. A method to assess target gene involvement in angiogenesis in vitro and in vivo using lentiviral vectors expressing shRNA.

    Directory of Open Access Journals (Sweden)

    Wayne Blosser

    Full Text Available Current methods to study angiogenesis in cancer growth and development can be difficult and costly, requiring extensive use of in vivo methodologies. Here, we utilized an in vitro adipocyte derived stem cell and endothelial colony forming cell (ADSC/ECFC co-culture system to investigate the effect of lentiviral-driven shRNA knockdown of target genes compared to a non-targeting shRNA control on cord formation using High Content Imaging. Cord formation was significantly reduced following knockdown of the VEGF receptor VEGFR2 in VEGF-driven cord formation and the FGF receptor FGFR1 in basic FGF (bFGF-driven cord formation. In addition, cord formation was significantly reduced following knockdown of the transcription factor forkhead box protein O1 (FOXO1, a protein with known positive effects on angiogenesis and blood vessel stabilization in VEGF- and bFGF-driven cord formation. Lentiviral shRNA also demonstrated utility for stable knockdown of VEGFR2 and FOXO1 in ECFCs, allowing for interrogation of protein knockdown effects on in vivo neoangiogenesis in a Matrigel plug assay. In addition to interrogating the effect of gene knockdown in endothelial cells, we utilized lentiviral shRNA to knockdown specificity protein 1 (SP1, a transcription factor involved in the expression of VEGF, in U-87 MG tumor cells to demonstrate the ability to analyze angiogenesis in vitro in a tumor-driven transwell cord formation system and in tumor angiogenesis in vivo. A significant reduction in tumor-driven cord formation, VEGF secretion, and in vivo tumor angiogenesis was observed upon SP1 knockdown. Therefore, evaluation of target gene knockdown effects in the in vitro co-culture cord formation assay in the ADSC/ECFC co-culture, ECFCs alone, and in tumor cells translated directly to in vivo results, indicating the in vitro method as a robust, cost-effective and efficient in vitro surrogate assay to investigate target gene involvement in endothelial or tumor cell

  20. 人Notch4基因RNAi慢病毒载体的构建及鉴定%Construction and identification of a lentiviral vector of RNA interference containing the human Notch4 gene

    Institute of Scientific and Technical Information of China (English)

    陈伟; 曹罡; 董震; 苏寒; 蒋勇; 张森林

    2013-01-01

    Objective Salivary adenoid cystic carcinoma (SACC) is a common malignancy in salivary glands, and the NotchA gene is involved in its development and metastasis. This stud)' aimed to construct and identify a lentiviral vector of RNA interference targeting human Notch4. Methods Based on the human NotchA gene sequences, RNAi target sequences were designed in accordance with RNAi sequence design principles, and cloned into the lentiviral vector pLenOR-THM by restriction endonuclease MIu 1 and Cla 1 double digestion and T4 DNA ligase ligation. After transformation into competent E. coll bacteria, the candidate clones were identified by DNA sequencing. The recombinant plasmid and the three packaging plasmids were co-transfected into the human embryonic kidney 293T cells by lipofectamine 2000 to produce the lentiviral particles, and the viral liter was determined. The 293T cells were infected with the lentiviral particles obtained and the transfection efficiency was assessed under the fluorescent microscope. Then the lentiviral vector particles were transfected into ACC-M cells and the expression of NotchA in the transfected cells was determined by QRT-PCR and Western blot. Results The lentiviral RNAi vector pLenOR-THM-Notch4 for the NotchA gene was constructed successfully. Strong green fluorescence was observed in the 293T cells under the fluorescent microscope after co-transfection of the cells with the 4 plasmids of the lentiviral vector. The virus in the supernatant reached a liter of 6. 2×108 TU/ml. The transfection efficiency of the collected virus exceeded 90% in the 293T cells with a multiplicity of infection of i. The second lentiviral vector significantly inhibited the expression of NotchA at both the mRNA and protein levels. Conclusion The lentiviral RNAi vector of NotchA has been successfully constructed and identified.%目的 涎腺腺样囊性癌(salivary adenoid cystic carcinoma,SACC)是涎腺常见的恶性肿瘤,Notch4基因与SACC的发生、

  1. Vector geometry

    CERN Document Server

    Robinson, Gilbert de B

    2011-01-01

    This brief undergraduate-level text by a prominent Cambridge-educated mathematician explores the relationship between algebra and geometry. An elementary course in plane geometry is the sole requirement for Gilbert de B. Robinson's text, which is the result of several years of teaching and learning the most effective methods from discussions with students. Topics include lines and planes, determinants and linear equations, matrices, groups and linear transformations, and vectors and vector spaces. Additional subjects range from conics and quadrics to homogeneous coordinates and projective geom

  2. Safety considerations in vector development.

    Science.gov (United States)

    Kappes, J C; Wu, X

    2001-11-01

    The inadvertent production of replication competent retrovirus (RCR) constitutes the principal safety concern for the use of lentiviral vectors in human clinical protocols. Because of limitations in animal models to evaluate lentiviral vectors for their potential to recombine and induce disease, the vector design itself should ensure against the emergence of RCR in vivo. Issues related to RCR generation and one approach to dealing with this problem are discussed in this chapter. To assess the risk of generating RCR, a highly sensitive biological assay was developed to specifically detect vector recombination in transduced cells. Analysis of lentiviral vector stocks has shown that recombination occurs during reverse transcription in primary target cells. Rejoining of viral protein-coding sequences of the packaging construct and cis-acting sequences of the vector was demonstrated to generate env-minus recombinants (LTR-gag-pol-LTR). Mobilization of recombinant lentiviral genomes was also demonstrated but was dependent on pseudotyping of the vector core with an exogenous envelope protein. 5' sequence analysis has demonstrated that recombinants consist of U3, R, U5, and the psi packaging signal joined with an open gag coding region. Analysis of the 3' end has mapped the point of vector recombination to the poly(A) tract of the packaging construct's mRNA. The state-of-the-art third generation packaging construct and SIN vector also have been shown to generate env-minus proviral recombinants capable of mobilizing retroviral DNA when pseudotyped with an exogenous envelope protein. A new class of HIV-based vector (trans-vector) was recently developed that splits the gag-pol component of the packaging construct into two parts: one that expresses Gag/Gag-Pro and another that expresses Pol (RT and IN) fused with Vpr. Unlike other lentiviral vectors, the trans-vector has not been shown to form recombinants capable of DNA mobilization. These results indicate the trans-vector

  3. 反义miRNA-21/ rAV-Tumstatin病毒载体对裸鼠膀胱癌生物学行为的影响%The biological behaviour influence of Anti-sense miRNA-21/ rAV- Tumstatin viral vector on nude mice bladder cancer

    Institute of Scientific and Technical Information of China (English)

    李然伟; 魏巍; 刘禄成; 温都苏; 陈秀玲

    2012-01-01

    目的 探讨反义miRNA-21/ rAV-Tumstatin病毒载体对裸鼠膀胱癌生长及转移的影响.方法 通过构建裸鼠原位膀胱癌移植瘤模型并灌注携带基因的腺病毒载体,观察肿瘤生长及盆腔淋巴结转移情况,同时采用免疫组化法检测肿瘤细胞增殖和凋亡指数.结果 肿瘤大小:治疗组为(14.60±5.31)mm2,对照组为(58.92±7.16)mm2,两组比较P<0.01;肿瘤细胞增殖率:治疗组为41.30%,对照组94.70%,两组相比P<0.05;凋亡指数治疗组和对照组分别是30.18和9.53,两者比较P<0.05;治疗组5只中无一只发生盆腔淋巴结转移,而对照组3只出现转移(60.0%),两组比较P<0.01.上述各项组间差异均有统计学意义.结论 反义miRNA-21/rAV-Tumstatin病毒载体对人膀胱癌裸鼠原位移植瘤具有良好的靶向性,能够通过抑制肿瘤细胞增殖和加速肿瘤细胞凋亡,遏制实验性裸鼠膀胱移植癌模型的生长转移,从而为该载体用于人类膀胱癌的治疗提供了一定的实验依据.%Objective To investigate the influence of anti-sense miRNA-21/ rAV-Tumstatin viral vector on nude mice bladder cancer growth and metastasis. Methods To establish nude mice situ bladder cancer model and pour into adenovirus vector with gene,observe the growth of tumor cell and transfer of pelvic cavity lymphaden, simultaneously use immunohistochemisty detecting proliferation and apoptotic index of tumor cell. Results Tumor size: treatment group(14. 60+5. 31)mm2, control group(58. 92 + 7. 16)mm2, two groups compare P<0. 01 ;proliferation rate of tumor cell: treatment group 41. 30% ,control group 94. 70% , two groups compare P<0. 05 ;apoptotic index of treatment and control group arc 30. 18 and 9. 53, two groups compare P<0. 05;no one happen pelvic cavity lymphaden metastasis in 5 treatment group,but control group 3 happen mctastasis(60. 0%),tow groups compare P<0. 01. The difference of a-bovc-mentioned each groups have statistical significance. Conclusion Anti

  4. Expression of microRNA-30c via lentivirus vector inhibits the proliferation and enhances the sensitivity of highly aggressive ccRCC Caki-1 cells to anticancer agents

    Science.gov (United States)

    Yang, Honglin; Song, Erlin; Shen, Guorong; Zhu, Tonghua; Jiang, Tingwang; Shen, Hao; Niu, Liping; Wang, Biao; Lu, Zhaoyang; Qian, Jianping

    2017-01-01

    The clear cell renal cell carcinoma (ccRCC) is one of the most fatal urologic tumors, and the prognosis remains very poor for advanced or metastatic ccRCC. This study reveals the roles of microRNA (miR)-30c in regulating a highly aggressive ccRCC cell line proliferation by targeting MTA-1, which is a key mediator for human cancer metastasis. Results from quantitative real-time polymerase chain reaction showed that the expression of MTA-1, the target of miR-30c, was significantly higher in metastatic ccRCC specimens than in nonmetastatic ccRCC or nontumor specimens. Accordingly, endogenous miR-30c is at a much lower level in highly aggressive ccRCC Caki-1 cells than nontumor or ccRCC cell lines. Expression of miR-30c via lentivirus vector inhibits the proliferation, anchorage-independent growth, in vitro invasion or migration, or in vivo growth of Caki-1 cells by repressing MTA-1 protein expression. miR-30c also enhances the sensitivity of Caki-1 cells to anticancer agents, including sorafenib and paclitaxel. These data reveal the potential application of miR-30c and that its targeting gene, MTA-1, would be a potential target in metastatic ccRCC treatment. PMID:28203091

  5. Vector velocimeter

    DEFF Research Database (Denmark)

    2012-01-01

    The present invention relates to a compact, reliable and low-cost vector velocimeter for example for determining velocities of particles suspended in a gas or fluid flow, or for determining velocity, displacement, rotation, or vibration of a solid surface, the vector velocimeter comprising a laser...... assembly for emission of a measurement beam for illumination of an object in a measurement volume with coherent light whereby a signal beam emanating from the object in the measurement volume is formed in response to illumination of the object by the measurement beam, a reference beam generator...... detector element signal when the fringe pattern formed by the interfering signal beam and reference beam moves across the first detector array; and a signal processor that is adapted for generation of a velocity signal corresponding to a first velocity component of movement of the object in the measurement...

  6. Vector velocimeter

    DEFF Research Database (Denmark)

    2012-01-01

    for generation of a reference beam, a detector system comprising a first detector arrangement arranged in such a way that the signal beam and the reference beam are incident upon the first detector arrangement with the reference beam propagating at an angle relative to a signal beam, and wherein the first......The present invention relates to a compact, reliable and low-cost vector velocimeter for example for determining velocities of particles suspended in a gas or fluid flow, or for determining velocity, displacement, rotation, or vibration of a solid surface, the vector velocimeter comprising a laser...... assembly for emission of a measurement beam for illumination of an object in a measurement volume with coherent light whereby a signal beam emanating from the object in the measurement volume is formed in response to illumination of the object by the measurement beam, a reference beam generator...

  7. Transcriptional Silencing of Retroviral Vectors

    DEFF Research Database (Denmark)

    Lund, Anders Henrik; Duch, M.; Pedersen, F.S.

    1996-01-01

    . Extinction of long-term vector expression has been observed after implantation of transduced hematopoietic cells as well as fibroblasts, myoblasts and hepatocytes. Here we review the influence of vector structure, integration site and cell type on transcriptional silencing. While down-regulation of proviral...... transcription is known from a number of cellular and animal models, major insight has been gained from studies in the germ line and embryonal cells of the mouse. Key elements for the transfer and expression of retroviral vectors, such as the viral transcriptional enhancer and the binding site for the t......RNA primer for reverse transcription may have a major influence on transcriptional silencing. Alterations of these elements of the vector backbone as well as the use of internal promoter elements from housekeeping genes may contribute to reduce transcriptional silencing. The use of cell culture and animal...

  8. Sindbis virus vectors for expression in animal cells.

    Science.gov (United States)

    Huang, H V

    1996-10-01

    Sindbis virus and other alphavirus gene expression vectors have recently been used to express and study the functions of proteins and RNA, to evaluate classical vaccine and novel antiviral approaches, and for nucleic acid immunization. The vectors will likely attract continuing, innovative applications that exploit their useful features: rapid and efficient gene expression, wide host range, and RNA genomes.

  9. Growth suppression effect of anti-sense miRNA-21/rAV-Tumstatin adenovirus vector on bladder cancer cell%反义miRNA-21/rAV-Tumstatin腺病毒载体对膀胱癌细胞生长的抑制作用

    Institute of Scientific and Technical Information of China (English)

    温都苏; 刘禄成; 魏巍; 李志; 郭航; 张明

    2012-01-01

    Objective To investigate the suppression effect of anti-sense miRNA-21/rAV-Tutnstatin adenovirus vector two-side target treatment on situ bladder transplanted tumor. Methods The anti-sense miRNA-21/rAV-Tumstatin was used on transplantation cancer by urethra irrigation of bladder, MTT way was applied to evaluate cell proliferation,TUNEL way was used to evaluate cell apoptosis. Results MTT way evaluating showed that nell growth rates of anti-sense miRNA-21, rAV-Tumstatin and combination groups were 48.7% ± 6. 2% 、 35.8% ±9.4% and 27. 8% ±3. 7%, which were obviously lower than those of control group(92. 8% ±7.4% ,P<0. 01). TUNEL way result showed that tumor cell apoptosis rates of 4 groups were in order:drug combination group(79. 3% ±4. 1% ) , anti-sense miRNA-21 group (51.2% ±7.5%), rAV-Tumstatin group(57.8% ±6.9%), control group(8.3% ±2. 6%),and the differences had statistical significance between the four groups (P < 0. 01). The tumor cell growth had been some more inhibited after vector treatment on 3 groups, but in combination group , the tumor cell growth was slowly, the difference had statistical significance ( P < 0.05) compared with the other two groups, furthermore, tumor cell growth was almost stasis state from 28 days. Conclusions Anti-sense miRNA-21 and rAV-Tumstatin alone applying could inhibit tumor cell proliferation and induce apoptosis, accordingly inhibit growth of bladder cancer cell, but two-side target drug which aim at carcinogene and anti-oncogene are significantly more useful than single drug, and more approach ideal treatment%目的 探讨反义miRNA-21/rAV-Tumstatin腺病毒载体双靶向治疗对裸鼠原位膀胱移植瘤生长的抑制作用.方法 应用携带反义miRNA-21/rAV-Tumstatin的载体经尿道膀胱灌注治疗移植癌.采用二苯基溴化四氮唑蓝(MTT)法测定瘤细胞的增殖,原位末端标记(TUNEL)法检测瘤细胞的凋亡.结果 MTI法检测结果显示,反义miRNA-21,rAV-Tumatin和联合应用组

  10. Vector nematicons

    CERN Document Server

    Horikis, Theodoros P

    2016-01-01

    Families of soliton pairs, namely vector solitons, are found within the context of a coupled nonlocal nonlinear Schrodinger system of equations, as appropriate for modeling beam propagation in nematic liquid crystals. In the focusing case, bright soliton pairs have been found to exist provided their amplitudes satisfy a specific condition. In our analytical approach, focused on the defocusing regime, we rely on a multiscale expansion methods, which reveals the existence of dark-dark and antidark-antidark solitons, obeying an effective Korteweg-de Vries equation, as well as dark-bright solitons, obeying an effective Mel'nikov system. These pairs are discriminated by the sign of a constant that links all physical parameters of the system to the amplitude of the stable continuous wave solutions, and, much like the focusing case, the solitons' amplitudes are linked leading to mutual guiding.

  11. Construction of CDH1 small interfering RNA enkaryotic vector ha rat immortalized neural progenitor cell and screening of the effective target site%大鼠永生化神经前体细胞CDH1小干扰RNA真核载体的构建

    Institute of Scientific and Technical Information of China (English)

    姚文龙; 张传汉; 柳璐; 祝畅; 邱瑾; 桂伶俐; 田玉科

    2008-01-01

    Objective To construct CDHI small interfering RNA eukaryofic vector in rat immortalized neural progenitor cell (INPC) and screen the effective target site. Methods Three hands of interfering sequences and one control sequence for CDHI small hairpin RNA were designed based on CDO1 coding sequence. Following the instructions on pENTR/H1/TO vector, the oligonuclcotides were synthesized, annealed and ligated into linearized pENTR/HI/TO vector, respectively. After confirmation by DNA sequencing, positive recombinant plasmids(CDO1 siRNAt, CDH1 siRNKz , CDH1 siRNA3 and CDH1 siRNA,)were transfected into INPCs respectively by the lipesome method. The pEGFP plasmid was transfected to evaluate the efficiency of transfection. Forty eight hours after transfection, total cellular RNA was extracted and the expression of CDH1 was analyzed by BT-PCR. Results The three eukaryotic vectors for CDHI siRNA and one control vector were successfully constructed and identified with DNA sequencing. The efficiency of cell transfection was (54 :t: 5) % at 24 h after transfection, (36 + 4) % at 48 h after transfection. The expression of CDH1 mRNA in INPC trandected with CDHI siRNA2 was lower than that of CDHI mRNA in INPC transfected with CDH1 siRNA~, and both the expression was lower than that of CDHI mRNA in INPC transfected with CDH1 siRNAs at 48 h after tmnsfectlon. Conclusion The effective small interfering RNA eukaryotic vector for CDH1 in INPC was successfully constructed and screened.%目的 构建大鼠永生化神经前体细胞(INPC)CDH1小干扰RNA(siRNA)真核载体.方法 根据大鼠CDH1基因的编码序列设计3个小发夹RNA(shRNA)干扰序列及1个阴性对照序列,根据pENTR/H1/TO中间载体说明书设计并合成相应的DNA单链,退火后分别连接到pENTR/H1/TO线性载体上,形成完整载体,提取CDH1 siRNA真核载体后(分别为CDH1 siRNA1、CDH1 siRNA2、CDH1siRNA3和CDH1 siRNA对照),进行DNA测序鉴定.采用Lipofectamine 2000

  12. 慢病毒载体介导RNA干扰体外抑制人胰腺癌细胞VIM基因的表达%Construction of a lentiviral vector for RNA interference of human VIM gene and its silencing effect in pancreatic cancer cells

    Institute of Scientific and Technical Information of China (English)

    Jianxin Jiang; Ming Shen; Renyi Qin; Rui Tian; Jing Li; Min Wang

    2009-01-01

    Objective: To construct a lentiviral expression vector for RNA interference (RNAi) of human VIM gene; and assess its gene silencing effect in pancreatic cancer cell line Panc-1. Methods: Three pairs of human VIM gene short hairpin RNA (shRNA) sequences were designed using a software available on-line and one pair came from document. After synthesis and annealing, four double-stranded oligonucleotides (dsOligo) were cloned into the pGCL-GFP/U6 plasmid, which were subsequently confirmed by polymerase chain reaction (PCR) and DNA sequencing analysis. Real-time PCR and Western blotting were used to screen the effective pGCL-GFP-shRNA plasmid in 293T cells, then the most effective one was packed into the recombinant lentivirus Lv-VIM-shRNA with lentiviral packing materials pHelper 1.0 and pHelper 2.0 in 293T cells.The titer of lentivirus was determined by hole-by-dilution titer assay. The silencing effect of Lv-VIM-shRNA in Panc-1 cells were validated by real-time PCR and Western-blotting. Results: An effective Lv-VIM-shRNA was successfully constructed.The titer of lentivirus was determined on 2×109TU/mL. The expressions of VIM mRNA and vimentin were down-regluated in the Panc-1 cells infected with Lv-VIM-shRNA. Conclusion: An effective Lv-VIM-shRNA could inhibit the expression of VIM gene in Panc-1 cells in vitro, which provides a tool for investigating the role of VIM gene in the signaling pathway involved in tumorigenesis and progression of pancreatic cancer and searching new therapeutic targets.

  13. Construction and identification of the reporter gene vectors of the 3’UTR region of insulin receptor mRNA including the wild or mutant miR-497 binding site%含miR-497野生及突变结合位点的胰岛素受体mRNA 3′UTR区报告基因载体的构建和鉴定

    Institute of Scientific and Technical Information of China (English)

    王美晨; 宁启兰; 李冬民; 王璇; 蓝茜; 李玥; 刘莉; 伊静; 李靖; 宋刘梅; 马莎蕊

    2014-01-01

    目的:利用 pmirGLO Dual-Luciferase miRNA Target Expression Vector(简称为pmirGLO 报告基因载体)构建并鉴定含 miR-497野生及突变结合位点的胰岛素受体 mRNA 3′UTR 区报告基因载体(pmir-Insr-3′UTR 及 pmir-mutant-Insr-3′UTR)。方法以大鼠肝脏 cDNA为模板,PCR 获取目的片段(即含 miR-497野生及突变结合位点的胰岛素受体 mRNA 3′UTR区);用PmeI、XbaI双酶切 pmirGLO 报告基因载体和含 miR-497野生及突变结合位点的胰岛素受体 mRNA 3′UTR区,用T4 DNA连接酶连接纯化后的酶切产物;连接产物转化DH5α大肠杆菌感受态细胞并挑选阳性克隆,并通过PCR、双酶切、DNA测序鉴定构建的重组质粒。结果 PCR和双酶切证实pmir-Insr-3′UTR及 pmir-mutant-Insr-3′UTR重组载体中均插入目的片段;DNA测序结果进一步证实 pmir-Insr-3′UTR重组载体中成功插入了胰岛素受体mRNA 3′UTR区,pmir-mutant-Insr-3′UTR重组载体中成功插入了在miR-497结合位点含有3个突变碱基的胰岛素受体 mRNA 3′UTR 片段。结论成功构建了含 miR-497野生及突变结合位点的胰岛素受体mRNA 3′UTR报告基因载体 pmir-Insr-3′UTR及 pmir-mutant-Insr-3′UTR。%Objective To construct and identify the reporter gene vectors of the 3′UTR region of insulin re-ceptor mRNA containing the wild or mutant miR-497 binding site (pmir-Insr-3′UTR and pmir-mutant-Insr-3′UTR) using pmirGLO dual-Luciferase miRNA target expression vector (pmirGLO report gene vector).Methods The target fragments,which were the 3′UTR region of rat insulin receptor mRNA,including wild or mutant miR-497 binding site,were obtained by PCR using rat liver cDNA as template.The target fragments and pmirGLO report gene vector were cut by PmeI and XbaI restriction endonucleases and then the purified enzyme-digested products were ligated together with a T4 DNA ligase.Subsequently,the ligation productions were used to transform DH5αcompetent cells

  14. Biosafety features of lentiviral vectors.

    Science.gov (United States)

    Schambach, Axel; Zychlinski, Daniela; Ehrnstroem, Birgitta; Baum, Christopher

    2013-02-01

    Over the past decades, lentiviral vectors have evolved as a benchmark tool for stable gene transfer into cells with a high replicative potential. Their relatively flexible genome and ability to transduce many forms of nondividing cells, combined with the potential for cell-specific pseudotyping, provides a rich resource for numerous applications in experimental platforms and therapeutic settings. Here, we give an overview of important biosafety features of lentiviral vectors, with detailed discussion of (i) the principles of the lentiviral split-genome design used for the construction of packaging cells; (ii) the relevance of modifications introduced into the lentiviral long terminal repeat (deletion of enhancer/promoter sequences and introduction of insulators); (iii) the basic features of mRNA processing, including the Rev/Rev-responsive element (RRE) interaction and the modifications of the 3' untranslated region of lentiviral vectors with various post-transcriptional regulatory elements affecting transcriptional termination, polyadenylation, and differentiation-specific degradation of mRNA; and (iv) the characteristic integration pattern with the associated risk of transcriptional interference with cellular genes. We conclude with considerations regarding the importance of cell targeting via envelope modifications. Along this course, we address canonical biosafety issues encountered with any type of viral vector: the risks of shedding, mobilization, germline transmission, immunogenicity, and insertional mutagenesis.

  15. Construction and effect of recombinant adenovirus vector containing siRNA targeting Raf-1 on cardiomyocyte hypertrophy in neonatal rats%Raf-1基因重组腺病毒 siRNA 载体构建及其对大鼠心肌细胞肥大的影响

    Institute of Scientific and Technical Information of China (English)

    郑亚萍; 刘春杰

    2016-01-01

    Objective To construct an adenovirus vector expressing small interfering RNA ( siRNA) targeting to rat Raf-1 gene and identify its function in cardiomyocytes.Methods The siRNA containing DNA sequence targeting to Raf-1 and its negative control sequence were designed, synthesized, annealed and subcloned into adenoviral shuttle vector pAdTrack-CMV.The recombinant adenovirus vector pAd-siRaf-1 was obtained by homologous recombination with pAdTrack-siRaf-1 linearized by PmeI and pAdeasy-1 in bacteria BJ5183, then transfected into HEK293 cells to package the adenovirus.Cardiomyocytes were infected with the adenovirus pAd-siRaf-1, and the expressions of Raf-1 and NF-κB protein were detected by Western blotting.[ 3 H ]-leu incorporation was evaluated by scintillation.The surface area of cardiomyocytes was measured using a HJ2000 image analysis system.Results The adenovirus vectors were verified by enzyme digestion and DNA sequencing.Compared with the Ang II group, Raf-1 and NF-κB expression, the surface area and [ 3 H]-leu incorporation of cardiomyocytes were significantly decreased in cardiomyocytes infected with the adenovirus PAd-siRaf-1.Conclusions A recombinant adenovirus vector containing rat siRaf-1 gene is successfully constructed.It can effectively reduce Raf-1 and NF-κB expression and cardiomyocyte hypertrophy induced by Ang II.%目的:构建特异性抑制大鼠Raf-1基因的重组腺病毒载体,并将其体外转导大鼠心肌细胞中进行功能鉴定。方法合成针对大鼠Raf-1的靶序列及阴性对照序列,经退火形成的DNA双链定向克隆到穿梭质粒pAdTrackCMV中获得pAdTrack-siRaf-1质粒,PmeI线性化后在BJ5183细菌中与pAdEasy-1骨架质粒进行同源重组获得pAd-siRaf-1质粒,后转染HEK293细胞,包装获得pAd-siRaf-1腺病毒颗粒,继而感染原代培养的心肌细胞,通过Western blot方法检测siRNA对Raf-1、NF-κB基因的抑制效率,液体闪烁计数仪测定3 H-亮氨酸([3 H

  16. Recombination of replicon and helper RNAs and the emergence of propagation-competent vectors upon Sindbis virus vector production.

    Science.gov (United States)

    Hyvärinen, Anna; Yongabi, Felicitas; Mäkinen, Kimmo; Wahlfors, Jarmo; Pellinen, Riikka

    2013-08-01

    Sindbis vectors have shown remarkable antitumor efficacy and tumor-targeting capacity in animal models and hold promise for cancer therapy. Different packaging systems are used to produce propagation-incompetent Sindbis vectors. However, the vectors produced using either DH-BB single helper RNA or split helper RNA can spread in permissive cell cultures. We investigated the mechanisms of vector spreading and show, here, that recombination occurs between the replicon and DH-BB helper RNA, leading to formation of the full-length virus genome. Split helper RNA may not completely prevent wild-type reversion, although the frequency is greatly reduced. Contrary to propagation of Sindbis DH-BB vectors, Sindbis split helper vectors were frequently able to spread without cytopathic effect (CPE), a feature that was linked to wild-type reversion. Our results support the hypothesis that the non-cytopathic local spreading constantly observed with Sindbis split helper vector results from unspecific packaging of helper RNAs into vector particles and co-infection with particles containing replicon and helper RNAs. Several malignant cell lines with defective interferon responses were found to be permissive for non-cytopathic spreading of the Sindbis split helper vector. Interferon-α suppressed the spreading providing a possible option to control the vector.

  17. RNA decay by messenger RNA interferases

    DEFF Research Database (Denmark)

    Christensen-Dalsgaard, Mikkel; Overgaard, Martin; Winther, Kristoffer Skovbo

    2008-01-01

    Two abundant toxin-antitoxin (TA) gene families, relBE and mazEF, encode mRNA cleaving enzymes whose ectopic overexpression abruptly inhibits translation and thereby induces a bacteriostatic condition. Here we describe and discuss protocols for the overproduction, purification, and analysis of mRNA...... cleaving enzymes such as RelE of Escherichia coli and the corresponding antitoxin RelB. In particular, we describe a set of plasmid vectors useful for the detailed analysis of cleavage sites in model mRNAs....

  18. Rotations with Rodrigues' Vector

    Science.gov (United States)

    Pina, E.

    2011-01-01

    The rotational dynamics was studied from the point of view of Rodrigues' vector. This vector is defined here by its connection with other forms of parametrization of the rotation matrix. The rotation matrix was expressed in terms of this vector. The angular velocity was computed using the components of Rodrigues' vector as coordinates. It appears…

  19. RNA helicases

    OpenAIRE

    Owttrim, George W.

    2013-01-01

    Similar to proteins, RNA molecules must fold into the correct conformation and associate with protein complexes in order to be functional within a cell. RNA helicases rearrange RNA secondary structure and RNA-protein interactions in an ATP-dependent reaction, performing crucial functions in all aspects of RNA metabolism. In prokaryotes, RNA helicase activity is associated with roles in housekeeping functions including RNA turnover, ribosome biogenesis, translation and small RNA metabolism. In...

  20. Construction and Identification of Transforming Growth Factor-β1 shRNA Expressing Vector%转化生长因子-β1 shRNA表达载体的构建与鉴定

    Institute of Scientific and Technical Information of China (English)

    张彪; 郭凌川; 董亮; 周赟; 吴淳; 胡欣; 潘展腾; 钟良君; 王守立

    2010-01-01

    目的 构建转化生长因子(TGF)-β1短发卡RNA(shRNA)表达载体,为肿瘤生物学研究奠定方法基础.方法 根据TGF-β1的mRNA序列,运用Ambion公司的Target Finder软件筛选TGF-β1shRNA的候选点,在BglⅡ和HindⅢ位点克隆到表达载体pSUPER gfp-neo上.重组的shRNA pSUPER gfp-neo在大肠杆菌DHSa上筛选和鉴定.分别用酶联免疫吸附法(ELISA)测定和免疫荧光筛选最佳TGF-β1shRNA靶点序列.结果 ELISA和免疫荧光染色结果显示,shRNA-a、shRNA-b和shRNA-c均在不同程度上降低了靶细胞TGF-β1蛋白质表达,以shRNA-b所引起的下降最为显著(P<0.05).结论 构建的TGF-β1shRNA在肿瘤细胞中产生较好的TGF-β1沉默效果,为肿瘤生物学研究提供了一种方法.

  1. RNA topology

    OpenAIRE

    Frank-Kamenetskii, Maxim D.

    2013-01-01

    A new variety on non-coding RNA has been discovered by several groups: circular RNA (circRNA). This discovery raises intriguing questions about the possibility of the existence of knotted RNA molecules and the existence of a new class of enzymes changing RNA topology, RNA topoisomerases.

  2. Concise vector analysis

    CERN Document Server

    Eliezer, C J; Maxwell, E A; Sneddon, I N

    1963-01-01

    Concise Vector Analysis is a five-chapter introductory account of the methods and techniques of vector analysis. These methods are indispensable tools in mathematics, physics, and engineering. The book is based on lectures given by the author in the University of Ceylon.The first two chapters deal with vector algebra. These chapters particularly present the addition, representation, and resolution of vectors. The next two chapters examine the various aspects and specificities of vector calculus. The last chapter looks into some standard applications of vector algebra and calculus.This book wil

  3. Light axial vector mesons

    CERN Document Server

    Chen, Kan; Liu, Xiang; Matsuki, Takayuki

    2015-01-01

    Inspired by the abundant experimental observation of axial vector states, we study whether the observed axial vector states can be categorized into the conventional axial vector meson family. In this paper we carry out analysis based on the mass spectra and two-body Okubo-Zweig-Iizuka-allowed decays. Besides testing the possible axial vector meson assignments, we also predict abundant information for their decays and the properties of some missing axial vector mesons, which are valuable to further experimental exploration of the observed and predicted axial vector mesons.

  4. 携带DNMT3b-shRNA干扰序列真核表达载体的构建及筛选%Construction and Selection of Eukaryotic Expression Vectors Carrying shRNA Targeting DNMT3b

    Institute of Scientific and Technical Information of China (English)

    张士龙; 曾甫清; 彭世波; 汪良

    2009-01-01

    目的:构建携带针对靶基因DNA甲基转移酶3b(DNA methyltransferase 3b,DNMT3b)mRNA的shRNA真核表达载体,并从构建成功的重组质粒中筛选出沉默效应最强的干扰质粒.方法:以基因DNMT3bmRNA为靶序列设计三条shRNA序列,应用基因重组技术将其克隆到真核表达载体pGensil-1中,构建重组质粒pGensil-1-DNMT3b-shRNA1、pGensil-1-DNMT3b-shRNA2、pGensil-1-DNMT3b-shRNA3;经酶切鉴定和测序分析后,将重组质粒分别转染T24细胞中,应用RT-PCR和Western-blot检测各组质粒对DNMT3bmRNA和蛋白的表达抑制情况,并筛选最有效的干扰序列.结果:各重组质粒经酶切鉴定和测序分析显示插入完全正确.RT-PCR结果经图像分析,shRNA1、shRNA2和shRNA3对DNMT3bmRNA的抑制率分别为20.44%、79.91%和54.48%;Western blot结果经图像分析,shRNA1、shRNA2和shRNA3对DNMT3b蛋白的抑制率分别为17.27%、77.74%和56.79%.结论:成功构建了质粒pGensi1-1-DNMT3b-shRNA(1,2,3),并筛选出pGensil-1-DNMT3b-shRNA2为沉默效应最强的质粒.

  5. Efficient than a Nonlentiviral Vector

    Directory of Open Access Journals (Sweden)

    Tao Yang

    2010-01-01

    Full Text Available Background. Lentiviral constructs reportedly can integrate into the genome of non-dividing, terminally differentiated cells and dividing cells, for long-term gene expression. This investigation tested whether a third generation lentiviral-mediated small interfering RNA (siRNA delivered into renal epithelial and fibroblast cells against type II transforming growth factor-beta receptor (siRNA-TBRII could better attenuate renal fibrogenesis in comparison with a non-lentiviral construct. Methods. HIV-derived lentiviral and non-lentiviral constructs were used to transfect cells with siRNA-TBRII or siRNA-EGFP control. Human embryonic kidney (HEK-293T, renal epithelial cells (NRK-52E and renal fibroblasts (NRK-49F were transfected and gene silencing quantified (fluorescence microscopy, Western blotting, fluorescence-activated cell sorting. Renal fibrogenesis was assessed using extracellular matrix protein synthesis (fibronectin and collagen-III; Western immunoblot, and α-smooth muscle actin (α-SMA was analysed as a marker of fibroblast activation and epithelial-to-mesenchymal transdifferentiation (EMT. Results. Lentiviral-mediated siRNA-TBRII significantly suppressed TBRII expression in all cell lines, and also significantly suppressed renal fibrogenesis. In comparison with the non-lentiviral construct, lentiviral-mediated siRNA-TBRII produced stronger and more persistent inhibition of collagen-III in NRK-49F cells, fibronectin in all renal cell lines, and α-SMA in renal epithelial cells. Conclusions. Lentiviral vector systems against TBRII can be delivered into renal cells to efficiently limit renal fibrogenesis by sequence-specific gene silencing.

  6. Cx43基因shRNA慢病毒载体的构建及其对大鼠心肌细胞Cx43基因的作用%Construction of a lentiviral vector for RNA interference targeting rat cardiac myocytes connexin 43 gene and its effect

    Institute of Scientific and Technical Information of China (English)

    陈立; 钟国强; 涂荣会; 黎庆捷; 何艳

    2013-01-01

    目的 构建缝隙连接蛋白(Cx)43基因shRNA慢病毒载体,并检测其对大鼠心肌细胞Cx43基因的作用.方法 针对Cx43基因序列,设计RNA干扰靶点序列,合成靶序列的双链DNA,接入pGCL-GFP载体,挑选阳性克隆行PCR鉴定及测序.用pHelper1.0和pHelper2.0质粒转染293T细胞,包装产生具备感染能力的慢病毒.以293T细胞中绿色荧光蛋白的细胞数量计算病毒滴度;以最适感染复数感染大鼠心肌细胞,通过荧光显微镜观察感染效率;应用real-time PCR和Western blot法检测大鼠心肌细胞.Cx43 mRNA及Cx43蛋白表达,并评价其抑制效果.结果 经PCR鉴定和测序证实,Cx43慢病毒载体构建正确,其病毒滴度为8×108 TU/mL、转染效率为82.59%.荧光定量real-time PCR法检测Cx43 mRNA的抑制率为96.10%,Western blot法检测Cx43蛋白的抑制率为77.16%.结论 成功构建了Cx43基因shRNA慢病毒载体,其能显著抑制大鼠心肌细胞Cx43基因的表达.%Objective To construct a lentiviral RNAi vector and to detect its effect on connexin 43 (Cx43) gene in rat cardiac myocytes.Methods Short hairpin RNA (shRNA) sequence targeting rat cardiac myocytes Cx43 gene was designed.After synthesis and annealing,the double-stranded oligonucleotides (ds oligo) were connecting to pGC-LV vectors.The positive clones were selected and conducted by PCR identification and sequencing.Then,The viral particles were gen erated by cotransfection of 293T cells with the pGC-lv-Cx43 and two packaging vector (pHelper1.0,pHelper2.0),and the virus titer was determined by counting the number of GFP positive cells.After transfection of lentiviral vector into rat cardiac myocytes with multiplicity of infection (MOI),the level of Cx43 mRNA in rat cardiac myocytes was determined by realtime PCR and the level of Cx43 protein was determined by Western blot assay.The inhibitory effect was evaluated.Results The construction of Cx43 lentiviral vector was confirmed by PCR identification

  7. VectorBase

    Data.gov (United States)

    U.S. Department of Health & Human Services — VectorBase is a Bioinformatics Resource Center for invertebrate vectors. It is one of four Bioinformatics Resource Centers funded by NIAID to provide web-based...

  8. Construction of short hairpin RNA eukaryotic expression vectors targeting peroxire- doxin Ⅰ and identification of their biological functions%靶向PeroxiredoxinⅠ基因的shRNA真核表达载体的构建及生物学功能鉴定

    Institute of Scientific and Technical Information of China (English)

    郭启帅; 黄曦; 张俊; 李少林

    2011-01-01

    Objective To construct short hairpin RNA (shRNA) eukaryotic expression vectors targeting peroxiredoxin Ⅰ ( Prx Ⅰ ) gene and investigate the effect of down-regulating Prx Ⅰ expression on the biological functions of breast carcinoma MCF-7 cells. Methods The eukaryotic expression vectors targeting Prx Ⅰ gene were constructed and then transfected into MCF-7 cells. Transfection efficiency was evaluated by flow cytometry. The mRNA and protein expressions of Prx Ⅰ in MCF-7 cells were detected by RT-PCR and Western blotting. The proliferation of MCF-7 cells was determined by MTT assay. The cell cycle and apoptosis were evaluated by flow cytometry. Results The eukaryotic expression vectors pGPU6-HK (negative control), pGPU6-Prxl, pGPU6-Prx2, pGPU6-Prx3 and pGPU6-Prx4 were successfully constructed and then transfected into MCF-7 cells respectively. Transfection efficiency was about 80%. The expression of Prx Ⅰ in MCF-7 cells transfected with 4 Prx vectors were inhibited significantly at both mRNA and protein levels, especially in the cells with pGPU6-Prx3, whose inhibitory rates were 82.6% and 80.5% respectively at mRNA and protein levels. When pGPU6-Prx3 group was compared with untransfected group and the group transfected with pGPU6HK, the cell proliferation was markedly delayed (P < 0. 05 ), the cell apoptosis rate was significantly increased, and the cells were arrested in G1 phase and S phase were significantly decreased (P < 0. 05 ).Conclusion Eukaryotic expression vectors of shRNA Prx Ⅰ is successfully constructed, and specifically downregulate the Prx Ⅰ expression at mRNA and protein levels. Transfection of pGPU6-Prx3 vector significantly inhibits cell proliferation, induces cell apoptosis, and regulates cell phase redistribution in MCF-7 cells.%目的 构建针对PeroxiredoxinⅠ(PrxⅠ)基因的短发夹RNA(short hairpin RNA, shRNA)真核表达载体,观察下调PrxⅠ基因表达后对乳腺癌MCF-7细胞生物学功能的影响.方法

  9. On Double Vector Bundles

    Institute of Scientific and Technical Information of China (English)

    Zhuo CHEN; Zhang Ju LIU; Yun He SHENG

    2014-01-01

    In this paper, we construct a category of short exact sequences of vector bundles and prove that it is equivalent to the category of double vector bundles. Moreover, operations on double vector bundles can be transferred to operations on the corresponding short exact sequences. In particular, we study the duality theory of double vector bundles in term of the corresponding short exact sequences. Examples including the jet bundle and the Atiyah algebroid are discussed.

  10. On Double Vector Bundles

    OpenAIRE

    Chen, Zhuo; Liu, Zhangju; Sheng, Yunhe

    2011-01-01

    In this paper, we construct a category of short exact sequences of vector bundles and prove that it is equivalent to the category of double vector bundles. Moreover, operations on double vector bundles can be transferred to operations on the corresponding short exact sequences. In particular, we study the duality theory of double vector bundles in term of the corresponding short exact sequences. Examples including the jet bundle and the Atiyah algebroid are discussed.

  11. Custodial vector model

    DEFF Research Database (Denmark)

    Becciolini, Diego; Franzosi, Diogo Buarque; Foadi, Roshan;

    2015-01-01

    We analyze the Large Hadron Collider (LHC) phenomenology of heavy vector resonances with a $SU(2)_L\\times SU(2)_R$ spectral global symmetry. This symmetry partially protects the electroweak S-parameter from large contributions of the vector resonances. The resulting custodial vector model spectrum...

  12. Custodial vector model

    DEFF Research Database (Denmark)

    Becciolini, Diego; Franzosi, Diogo Buarque; Foadi, Roshan

    2015-01-01

    We analyze the Large Hadron Collider (LHC) phenomenology of heavy vector resonances with a $SU(2)_L\\times SU(2)_R$ spectral global symmetry. This symmetry partially protects the electroweak S-parameter from large contributions of the vector resonances. The resulting custodial vector model spectrum...

  13. Construction of Retrovirus Expressing CTGF siRNA Mediated by PRS Retrovirus Vector%PRS载体介导的表达CTGF-SiRNA逆转录病毒载体的构建

    Institute of Scientific and Technical Information of China (English)

    肖力; 刘伏友; 彭佑铭; 袁芳; 陈俊香

    2006-01-01

    [目的]构建表达人结缔组织生长因子(CTGF)小分子干扰RNA(small interfering RNA,SiRNA)的PRS-CTGF-SiRNA逆转录病毒载体.[方法]根据SiRNA靶序列设计要求及PRS逆转录病毒载体特点分别设计含64 bp DNA序列的4对寡核苷酸,并在体外合成.PRS载体用BgⅡ、HindⅢ双酶切完全后,分别与退火的4对寡核苷酸进行连接,连接后去载体自连,构建成表达人CTGF小分子干扰RNA的PRS-CTGF-SiRNA逆转录病毒载体.[结果]经酶切、连接后构建成的质粒称之为PRS-CTGF-SiRNA1~4,经酶切与测序证实构建成功,无任何碱基突变.[结论]成功构建了能表达人CTGF-SiRNA的PRS-CTGF-SiRNA逆转录病毒载体,为腹膜透析腹膜纤维化防治的体内、外研究提供一种可能有效的方法.

  14. Construction of shRNA eukaryotic expression vectors targeting PERK gene and effect of PERK gene knockdown on apoptosis in endoplasmic reticulum stress-induced L02 hepatocytes%靶向PERK基因的shRNA真核表达载体的构建及对内质网应激状态下L02肝细胞凋亡的影响

    Institute of Scientific and Technical Information of China (English)

    曹洁; 杨朝霞; 沈薇; 姚隆

    2011-01-01

    AIM: To construct short hairpin RNA ( shRNA ) eukaryotic expression vectors targeting the gene of RNA - dependent protein kinase ( PKR ) - like endoplasmic reticulum kinase ( PERK ), and to observe the effect of PERK gene knockdown on apoptosis of human normal hepatic L02 cells treated with thapsigargin. METHODS: Three shRNA expression vectors targeting PERK gene, named PERK1 - shRNA, PERK2 - shRNA and PERKS - shRNA, and one non -homologous negative control expression vector ( HK - shRNA ) were constructed based on the nucleotide sequence of PERK and the criteria of designing small interfering RNA ( siRNA ), and were identified by enzyme digestion and DNA sequencing analysis. After L02 hepatocytes were transfected with the plasmids, the PERK expression was determined by RT - PCR and Western blotting, and the plasmid with the best inhibitory effect on PERK expression was screened. The cell viability and apoptotic rate of L02 hepatocytes transfected with PERK - shRNA under endoplasmic reticulum stress ( ERS ) were measured by the methods of MTT and flow cytometry,respectively. RESULTS: Four shRNA expression vectors were constructed. The mRNA and protein expression levels of PERK gene decreased significantly in L02 hepatocytes transfected with PERK1 - shRNA, PERK2 - shRNA and PERK3 - shRNA as compared with those in control cells ( P <0. 05 ). The inter-fering effect of PERK1 - shRNA on PERK gene expression was the best. PERK knockdown by PERK1 - shRNA increased the viability and inhibited the apoptosis of L02 cells under ERS. CONCLUSION: The shRNA expression vectors targeting PERK gene are constructed, and PERK gene knockdown may inhibit apoptosis in L02 hepatocytes under ERS.%目的:构建靶向RNA依赖的蛋白激酶样内质网激酶(PERK)基因的短发夹状RNA(shRNA)真核表达载体,观察其对内质网应激(ERS)状态下人正常肝细胞株L02凋亡的影响.方法:根据PERK基因核苷酸序列,按照小干扰RNA(siRNA)靶序列的设计原则,设

  15. PolI-driven integrative expression vectors for yeast.

    Science.gov (United States)

    Blancafort, P; Ferbeyre, G; Sariol, C; Cedergren, R

    1997-07-23

    A novel expression vector for yeast has been constructed from the regulatory elements present in the polI promoter and the enhancer/termination region (E/T) of rDNA. Under some conditions, this promoter/vector combination produces small RNAs such as the hammerhead RNA sequence at levels comparable to polII- and polIII-dependent systems. No stable transcription product can be demonstrated with this vector when the enhancer/termination sequence is less than 100 nucleotides downstream from the promoter. On the other hand, high expression of a stable, hammerhead RNA molecule can be obtained from this vector by inserting a 400-bp fragment containing the ADH1 transcription termination region upstream of the E/T. RNAs produced by this vector are polyadenylated and multiple copies of this plasmid can be stably integrated into the yeast chromosome.

  16. RNA interference and antiviral therapy

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    RNA interference (RNAi) is an evolutionally conserved gene silencing mechanism present in a variety of eukaryotic species. RNAi uses short double-stranded RNA (dsRNA) to trigger degradation or translation repression of homologous RNA targets in a sequence-specific manner. This system can be induced effectively in vitro and in vivo by direct application of small interfering RNAs (siRNAs), or by expression of short hairpin RNA (shRNA) with non-viral and viral vectors. To date, RNAi has been extensively used as a novel and effective tool for functional genomic studies, and has displayed great potential in treating human diseases, including human genetic and acquired disorders such as cancer and viral infections. In the present review, we focus on the recent development in the use of RNAi in the prevention and treatment of viral infections. The mechanisms,strategies, hurdles and prospects of employing RNAi in the pharmaceutical industry are also discussed.

  17. Vector Soliton Fiber Lasers

    CERN Document Server

    Zhang, Han

    2011-01-01

    Solitons, as stable localized wave packets that can propagate long distance in dispersive media without changing their shapes, are ubiquitous in nonlinear physical systems. Since the first experimental realization of optical bright solitons in the anomalous dispersion single mode fibers (SMF) by Mollenauer et al. in 1980 and optical dark solitons in the normal dispersion SMFs by P. Emplit et al. in 1987, optical solitons in SMFs had been extensively investigated. In reality a SMF always supports two orthogonal polarization modes. Taking fiber birefringence into account, it was later theoretically predicted that various types of vector solitons, including the bright-bright vector solitons, dark-dark vector solitons and dark-bright vector solitons, could be formed in SMFs. However, except the bright-bright type of vector solitons, other types of vector solitons are so far lack of clear experimental evidence. Optical solitons have been observed not only in the SMFs but also in mode locked fiber lasers. It has be...

  18. Vehicle Based Vector Sensor

    Science.gov (United States)

    2015-09-28

    300001 1 of 16 VEHICLE-BASED VECTOR SENSOR STATEMENT OF GOVERNMENT INTEREST [0001] The invention described herein may be manufactured and...unmanned underwater vehicle that can function as an acoustic vector sensor . (2) Description of the Prior Art [0004] It is known that a propagating...mechanics. An acoustic vector sensor measures the particle motion via an accelerometer and combines Attorney Docket No. 300001 2 of 16 the

  19. Implicit Real Vector Automata

    Directory of Open Access Journals (Sweden)

    Jean-François Degbomont

    2010-10-01

    Full Text Available This paper addresses the symbolic representation of non-convex real polyhedra, i.e., sets of real vectors satisfying arbitrary Boolean combinations of linear constraints. We develop an original data structure for representing such sets, based on an implicit and concise encoding of a known structure, the Real Vector Automaton. The resulting formalism provides a canonical representation of polyhedra, is closed under Boolean operators, and admits an efficient decision procedure for testing the membership of a vector.

  20. RNA Crystallization

    Science.gov (United States)

    Golden, Barbara L.; Kundrot, Craig E.

    2003-01-01

    RNA molecules may be crystallized using variations of the methods developed for protein crystallography. As the technology has become available to syntheisize and purify RNA molecules in the quantities and with the quality that is required for crystallography, the field of RNA structure has exploded. The first consideration when crystallizing an RNA is the sequence, which may be varied in a rational way to enhance crystallizability or prevent formation of alternate structures. Once a sequence has been designed, the RNA may be synthesized chemically by solid-state synthesis, or it may be produced enzymatically using RNA polymerase and an appropriate DNA template. Purification of milligram quantities of RNA can be accomplished by HPLC or gel electrophoresis. As with proteins, crystallization of RNA is usually accomplished by vapor diffusion techniques. There are several considerations that are either unique to RNA crystallization or more important for RNA crystallization. Techniques for design, synthesis, purification, and crystallization of RNAs will be reviewed here.

  1. Vectors and their applications

    CERN Document Server

    Pettofrezzo, Anthony J

    2005-01-01

    Geared toward undergraduate students, this text illustrates the use of vectors as a mathematical tool in plane synthetic geometry, plane and spherical trigonometry, and analytic geometry of two- and three-dimensional space. Its rigorous development includes a complete treatment of the algebra of vectors in the first two chapters.Among the text's outstanding features are numbered definitions and theorems in the development of vector algebra, which appear in italics for easy reference. Most of the theorems include proofs, and coordinate position vectors receive an in-depth treatment. Key concept

  2. Complex Polynomial Vector Fields

    DEFF Research Database (Denmark)

    Dias, Kealey

    vector fields. Since the class of complex polynomial vector fields in the plane is natural to consider, it is remarkable that its study has only begun very recently. There are numerous fundamental questions that are still open, both in the general classification of these vector fields, the decomposition...... or meromorphic (allowing poles as singularities) functions. There already exists a well-developed theory for iterative holomorphic dynamical systems, and successful relations found between iteration theory and flows of vector fields have been one of the main motivations for the recent interest in holomorphic...

  3. Construction of RNA Interference Vector of Coat Protein Gene of Grapevine Fanleaf Virus and the Effect Evaluation in Transgenic Nicotiana benthamiana%GFLVCP 基因 RNAi 载体构建及其在转基因烟草中的干涉效果

    Institute of Scientific and Technical Information of China (English)

    田莉莉; 牛良

    2014-01-01

    In order to probe the efficiency of the RNAi strategy in protection plants against GFLV ,we cloned a conserved segment of coat protein gene of GFLV (310 bp) by RT-PCR,constructed a RNAi plant expression vector by introducing this fragment into the destination vector of pHELLSGATE 12 by gateway technology ,and transformed into Nicotiana benthamiana by Agrobaterium mediated method .RT-PCR identification showed that the target gene fragment was integrated into the tobacco genome and showed expression in RNA level .We also evaluated the virus-resistance of the plants by virus inoculation.The results showed that the rate of disease occurrence in the transgenic positive lines was obviously lower than the control , indicating that the expressed dsRNAs in the transgenic plants may interfere the infection of this virus .%为探讨RNAi策略在抗GFLV基因工程中的效果,通过RT-PCR克隆获得了310 bp的GFLV外壳蛋白基因保守片段,采用Gateway技术将该基因片段连入目标载体pHELLSGATE12构建了RNAi植物表达载体,并通过农杆菌介导法转入烟草中,RT-PCR检测表明目的基因片段已整合到烟草基因组中并在RNA 水平上得到表达,病毒接种结果显示阳性植株的发病率明显低于对照,说明在转基因植株中dsRNA表达可干涉GFLV侵染过程。

  4. Construction of Cyclin D1 siRNA Vector and Effect on Proliferation of Human HepG2 Cancer Cells%Cyclin D1-siRNA真核质粒的构建及对HepG2肝癌细胞增殖的影响

    Institute of Scientific and Technical Information of China (English)

    王一; 连小云; 张玎; 王晖; 王岐山

    2011-01-01

    Objective To explore the effect of cyclinDl gene blocking by siRNA on proliferation and cell cycle of HepG2 liver caicenoma cells. Methods Four pairs of DNA templates coding siRNA,synthesized against cyclinDl and cloned into the vector PGE-l?were identified by restriction ndonuclease digestion analysis,PCR and DNA sequencing cells were then transfected with these four PGE-1-siRNAs and the negative control. After G418 selection,RT-PCR and Western blot were used to detect the expression of cyclinDl gene. Cell growth curve were drived by MTT assays. Results Restriction en-donuclease digestion analysis and DNA sequencing results all showed that the target segments were cloned PGE-1 vector respectively after the postive-siRNA was chosen to transfected into HepG2 cells,the expression of cyclinDlmRNA and protein was marketly decreased. The results showed that after interfering,the HepG2 cells cell growth were signifencantly inhibited. Conclusion The cyclinDl-specific siRNA mediated by PGE-1 could effectively knockdown the expression of gene and inhibits the proliferation potential ability of HepG2 cells.%目的 利用PGE-1建立针对抑制cyclinD1功能的siRNA 真核表达载体以及对肝癌HepG2细胞增殖和周期的影响.方法 针对cyclinD1 mRNA序列设计合成4对寡核苷酸,退火后连接到PGE-1质粒中,PCR及测序鉴定.用脂质体将重组质粒转染到HepG2中,RT-PCR cyclinD1 mRNA的表达,G418筛选后用RT-PCR和Westernblot技术分别检测cyclinD1 mRNA和蛋白质水平;流式细胞仪测定细胞周期的变化;MTT法测定细胞的生长.结果 在设计的4条靶序列中有一序列重组成质粒后,可明显抑制cyclinD1的表达;目的 序列表达载体转染HepG2细胞后,可以明显减少G2-M期细胞的比例,当HepG2细胞稳定转染针对cyclinD1的干扰质粒后,mRNA和蛋白质的表达也明显降低;HepG2细胞cyclinD1表达降低后,其生长也受到明显抑制.结论 成功构建针对siRNA-cyclinD1真核质粒,在体

  5. HIF-1α基因RNA干扰质粒在胃癌细胞中的构建与鉴定%Construction of a vector carrying a small hairpin RNA targeting the HIF-1α gene and its expression in gastric cancer cells

    Institute of Scientific and Technical Information of China (English)

    龚青; 方淑环; 高国全

    2012-01-01

    AIM: To construct a plasmid carrying a small hairpin RNA (shRNA) targeting the HIF-lct gene and to observe its expression in gastric cancer SGC-7901 cells. METHODS: SHIF-la-specific shRNA sequence was designed, synthesized and cloned into the expression vector pSilencer 1.0-U6. The recombi-nants were identified by double digestion with EcoR I + Apa I and DNA sequencing, and then transfected into SGC-7901 cells under hypoxia. Forty-eight hours after transfection, HIF-la expression was detected by Western blotting. RESULTS: Restriction enzyme digestion and DNA sequencing confirmed that the shRNA was correctly inserted into the plasmid pSilenc-er 1.0-U6. The recombinant plasmid carrying the shRNA targeting HIF-la was successfully transfected into SGC-7901 cells. Western blot analysis suggested that HIF-la expression was knocked down in transfected cells compared to control cells. CONCLUSION: A plasmid carrying a shRNA targeting HIF-la has been constructed successfully, and SGC-7901 cells stably transfected with this recombinant vector have been obtained. These will offer favorable tools for studying HIF-la-targeted gene therapy.%目的:构建转录因子HIF-1α表达的RNA干扰(RNA interference,RNAi)质粒,为研究HIF-1α参与的细胞信号通路及以HIF-1α为靶点的基因治疗提供稳定转染细胞的RNAi.方法:选取HIF-1α基因的19nt特异性序列,设计针对HIF-1α的shRNA序列,应用基因重组技术克隆到pSilencer 1.0-U6表达载体中,利用EcoRⅠ和paⅠ双酶切和DNA测序鉴定重组克隆.低氧条件下,将包含HIF-1α基因RNAi序列的重组载体转染人胃癌细胞SGC-7901,转染48 h后,收集细胞裂解液,Western blotting分析低氧条件下对照组与转染组HIF-1α蛋白的表达水平.结果:双酶切证实shRNA插入pSilencer 1.0-U6质粒,DNA测序证实插入的序列正确;HIF-1α基因RNAi质粒转染胃癌细胞SGC-7901成功;Western blotting结果显示与空质粒对照组比转染组细胞HIF-1α表达下

  6. Constructing and identifying a lentiviral vector of RNA interference targeting matrix metalloproteinases-3 gene in human degenerative nucleus pulposus cells%人基质金属蛋白酶3基因RNA慢病毒载体构建及在人退变髓核细胞中的鉴定

    Institute of Scientific and Technical Information of China (English)

    曹进; 傅培荣; 房晶; 杨建坤; 位华卫; 李思源; 高峰; 西永明

    2016-01-01

    BACKGROUND: Inhibiting the degradation of extracellular matrix in the intervertebral disc can delay the degenerative process of intervertebral disc. Matrix metalloproteinases-3 (MMP3) is considered as a key enzyme for degradation of extracelular matrix components such as type II collagen and aggrecan. OBJECTIVE:To construct the short hairpin RNA lentiviral vector targeting human MMP3 gene and to detect its efficiency of gene silence by infecting human degenerative nucleus pulposus cells. METHODS:According to the human MMP3 mRNA (NM_002422.4) sequence, four groups of the short hairpin RNA gene sequences targeting MMP3 were designed, synthesized and annealed to form double stranded DNA fragments, which were connected with the LV3 vectors digested by BamHI andEcoRI enzymes, and then transfected into the competent cels. The positive clones were identified by PCR, and analyzed by sequencing. The packaging and titer of lentivirus were determined after transfecting 293T cells. Human degenerative nucleus pulposus cels were infected with lentivirus vector, and the transfection efficiency of each group was observed under inverted fluorescence microscope. The interfering efficiency was detected by real time-PCR and western blot at 72 and 96 hours. RESULTS AND CONCLUSION:The ds-oligo DNA was successfully inserted into the lentiviral vector as confirmed by electrophoresis and sequence analysis. The recombinant lentivirus was harvested from 293T cels with a viral titer of 1-5 ×108 TU/mL. RNA interference targeting the GCC AGG CTT TCC CAA GCA AAT sequences with the highest interfering efficiency in MMP3 gene at 72 and 96 hours resulted in suppression of MMP3 mRNA expression by 98% and 72%, respectively; and at 96 hours, the interfering efficiency of protein expression was 57.2%. The recombinant lentivirus vector containing RNA interference targeting MMP3 gene is successfuly constructed, which lays a foundation for further studies on the MMP3 function and gene therapy.%背景:

  7. Construction and identification of replication recombinent adenovirus vector of mice LINGO-1 shRNA%含鼠LINGO-1 shRNA重组腺病毒载体的构建和鉴定

    Institute of Scientific and Technical Information of China (English)

    高峰; 孙红辉; 杨有庚

    2009-01-01

    目的 构建含鼠LINGO-1短发夹RNA(short hairpin RNA,shRNA)的复制缺陷型腺病毒载体.方法 通过PCR法将带有LINGO-1 shRNA序列构建至U6启动子(U6sh LINGO-1)下游,与T载体连接,将质粒转化入大肠杆菌.将U6sh LINGO-1连到穿梭质粒pDC316上,与腺病毒基因组质粒pBHGlox△E1、3Cre共转染293T细胞,得到重组腺病毒载体(rAd LINGO-1).经PCR鉴定正确后,进行扩增、纯化、滴度测定及感染性鉴定.结果 PCR法得到U6sh LINGO-1,rAd LINGO-1具有良好的感染性,腺病毒滴度可达109TCID50/ml.双引物PCR法鉴定Ad LINGO-1可扩增出Ad及特异性片段U6sh LINGO-1.结论 成功构建了能表达LINGO-1 shRNA的重组腺病毒载体rAd LINGO-1,可能为临床应用RNA干涉技术促进脊髓损伤的恢复提供新的方法.

  8. PRS-CTGF-SiRNA逆转录病毒载体及包装细胞株的构建%Construction of retrovirus expressing CTGF siRNA and its steady packaging cell line mediated by PRS retrovirus vector

    Institute of Scientific and Technical Information of China (English)

    肖力; 刘伏友; 肖平; 彭佑铭; 段绍斌; 刘虹; 刘映红

    2007-01-01

    目的 用PRS逆转录病毒载体构建介导人结缔组织生长因子(CTGF)小分子干扰RNA(small interfering RNA,sRNA)表达的PRS-CTGF-SiRNA逆转录病毒载体,并建立高效、稳定表达CTGF-SiRNA的包装细胞株.方法 根据siRNA靶序列设计要求及PRS逆转录病毒载体特点分别设计含64bp DNA序列的4对寡核苷酸,并在体外合成.PRS载体用BglⅡ、HindⅢ双酶切完全后,分别与退火的4对寡核苷酸进行连接,构建成表达CTGF小分子干扰RNA的pRS-CTGF-SiRNA逆转录病毒载体.用脂质体2000介导转染PT67包装细胞,经抗性筛选,挑单克隆,扩大培养,用NIH3T3细胞测定病毒滴度,筛选出高效产毒细胞株.结果 经酶切、连接后构建成的质粒称之为PRS-CTGF-SiRNA1~4,经酶切与测序证实构建成功,无任何碱基突变.经脂质体介导转染包装细胞、抗性筛选和NIH3T3测定病毒滴度,筛选出具有高病毒滴度的细胞集落,扩大培养后建立CTGF-SiRNA高效表达的包装细胞株.结论 成功构建了能表达CTGFsiRNA的PRS-CTGF-SiRNA逆转录病毒载体,并建立了稳定、高效生产有活性的的CTGF-SiRNA产毒包装细胞株.

  9. Construction of eukaryotic vector expressing shRNA of ovarian cancer associated antigen CD147%CD147 shRNA真核表达质粒的构建及鉴定

    Institute of Scientific and Technical Information of China (English)

    邹伟; 辛晓燕; 杨红; 侯向华

    2005-01-01

    目的针对CD147基因的不同部位,构建不同CD147 shRNA表达质粒载体,在转录后水平抑制CD147的表达,对其克隆进行鉴定并挑选出抑制效率最高的克隆.方法用DNA重组技术将针对人CD147基因的不同部位所设计的3对shRNA序列克隆到真核表达质粒pGE-1中,构建CD147 shRNA表达质粒载体pGE-1 CD147shRNA1、2、3.用阳离子脂质体介导转染人卵巢癌高转移细胞系HO-8910pm,经G418筛选后获得克隆进行鉴定.结果3个CD147 shRNA表达载体pGE-1CD147shRNA1、2、3经PCR、限制性酶切及部分序列分析证明基因插入正确.半定量RT-PCR、Western blotting均证实:转染细胞8910 pm/pGE-1 CD147shRNA,与亲本细胞相比,CD147的表达在mRNA和蛋白水平均明显下降.结论成功构建了CD147 shRNA表达载体pGE-1 CD147shRNA,并筛选出特异而高效地阻断CD147表达的克隆.此实验结果为进一步研究CD147蛋白分子的生物学功能及应用奠定了基础,并对shRNA设计靶序列的选择有一定指导意义.

  10. Advancing vector biology research

    NARCIS (Netherlands)

    Kohl, Alain; Pondeville, Emilie; Schnettler, Esther; Crisanti, Andrea; Supparo, Clelia; Christophides, George K.; Kersey, Paul J.; Maslen, Gareth L.; Takken, Willem; Koenraadt, Constantianus J.M.; Oliva, Clelia F.; Busquets, Núria; Abad, F.X.; Failloux, Anna Bella; Levashina, Elena A.; Wilson, Anthony J.; Veronesi, Eva; Pichard, Maëlle; Arnaud Marsh, Sarah; Simard, Frédéric; Vernick, Kenneth D.

    2016-01-01

    Vector-borne pathogens impact public health, animal production, and animal welfare. Research on arthropod vectors such as mosquitoes, ticks, sandflies, and midges which transmit pathogens to humans and economically important animals is crucial for development of new control measures that target t

  11. Complex Polynomial Vector Fields

    DEFF Research Database (Denmark)

    Dias, Kealey

    or meromorphic (allowing poles as singularities) functions. There already exists a well-developed theory for iterative holomorphic dynamical systems, and successful relations found between iteration theory and flows of vector fields have been one of the main motivations for the recent interest in holomorphic...... vector fields. Since the class of complex polynomial vector fields in the plane is natural to consider, it is remarkable that its study has only begun very recently. There are numerous fundamental questions that are still open, both in the general classification of these vector fields, the decomposition...... of parameter spaces into structurally stable domains, and a description of the bifurcations. For this reason, the talk will focus on these questions for complex polynomial vector fields....

  12. Complex Polynomial Vector Fields

    DEFF Research Database (Denmark)

    The two branches of dynamical systems, continuous and discrete, correspond to the study of differential equations (vector fields) and iteration of mappings respectively. In holomorphic dynamics, the systems studied are restricted to those described by holomorphic (complex analytic) functions...... vector fields. Since the class of complex polynomial vector fields in the plane is natural to consider, it is remarkable that its study has only begun very recently. There are numerous fundamental questions that are still open, both in the general classification of these vector fields, the decomposition...... of parameter spaces into structurally stable domains, and a description of the bifurcations. For this reason, the talk will focus on these questions for complex polynomial vector fields....

  13. Complex Polynomial Vector Fields

    DEFF Research Database (Denmark)

    Dias, Kealey

    The two branches of dynamical systems, continuous and discrete, correspond to the study of differential equations (vector fields) and iteration of mappings respectively. In holomorphic dynamics, the systems studied are restricted to those described by holomorphic (complex analytic) functions...... or meromorphic (allowing poles as singularities) functions. There already exists a well-developed theory for iterative holomorphic dynamical systems, and successful relations found between iteration theory and flows of vector fields have been one of the main motivations for the recent interest in holomorphic...... vector fields. Since the class of complex polynomial vector fields in the plane is natural to consider, it is remarkable that its study has only begun very recently. There are numerous fundamental questions that are still open, both in the general classification of these vector fields, the decomposition...

  14. 携带TRAIL基因的条件复制型腺病毒载体的构建及其辐射诱导表达%Construction of conditionally replicative adenovirus vector carrying TRAIL gene and its mRNA and protein expressions induced by ionizing radiation

    Institute of Scientific and Technical Information of China (English)

    王宏芳; 吴嘉慧; 刘纯岩; 刘威武; 孙延红; 龚守良; 王志成; 刘扬

    2014-01-01

    Objective To construct the conditionally replicative adenovirus vector pAd-Egr1-TRAIL-hTERT-E1A-E1Bp-E1B55K carrying early growth response gene-1 (Egr1)promoter and tumor necrosis factor related apoptosis inducing ligand (TRAIL)gene, and to observe the effects of the vector combined with 2 Gy irradiation on the TRAIL expression in MDA-MB-231 cells.Methods Egr-1 promotor sequence was cloned from pMD18 T-Egr1, TRAIL was constructed the downstream of Egr1 promoter, pShuttle-Egr1-TRAIL-hTERT-E1A-E1Bp-E1B55K (CRAd.pEgr1-TRAIL)was constructed,after the adenovirus vector was packaged successfully,MDA-MB-231 cells were infected with them and irradiated with X-rays.Real time PCR method and ELISA were used to detect the expression levels of TRAIL mRNA and protein, respectively. Six groups in the experiment were set up:control, 2 Gy,CRAd.p,CRAd.pEgr1-TRAIL,CRAd.p + 2 Gy and CRAd.pEgr1-TRAIL + 2 Gy. Results The recombinant adenovirus vector pAd-Egr1-TRAIL-hTERT-E1A-E1Bp-E1B55K was constructed and packaged successfully.The expression level of TRAIL mRNA in MDA-MB-231 cells transfected with the vector of 5 MOI for 24 h following 2.0 Gy X-rays irradiation began to increase and arrived to the top 8 h later in various groups,then declined.The expression level of TRAIL protein in MDA-MB-231 cells began to increase 6 h after irradiation and reached to the peak 24 h later,then declined 48 h later.There were significant differences in the expression levels of TRAIL protein between CRAd.pEgr1-TRAIL + 2.0 Gy and other groups at the same time point (P<0.01). Conclusion The recombinant adenovirus vector is obtained successfully, and the TRAIL mRNA and protein expression levels in MDA-MB-231 cells can be increased significantly by the vector combined with 2.0 Gy X-rays irradiation.%目的:构建携带早期生长反应基因-1(Egr-1)启动子和肿瘤坏死因子相关的凋亡诱导配体(TRAIL)基因的条件复制型腺病毒载体 pAd-Egr1-TRAIL-hTERT-E1A-E1Bp-E1B55K

  15. Construction of miRNA expression vector dual-targeting on HIF-1α/ survivin genes and its effects on proliferation of pancreatic cancer Panc-1 cell line%抗HIF-1α和survivin基因双靶位miR-RNAi载体的构建及其对胰腺癌细胞的作用

    Institute of Scientific and Technical Information of China (English)

    徐孙兵; 朱一平; 牟一平; 朱玲华

    2012-01-01

    目的:构建抗HIF-1α单靶位(anti-H)、抗Survivin单靶位(anti-S)以及抗HIF-1α和Survivin基因双靶位微小RNA表达载体(anti-H+S),观察和比较这3种载体对胰腺癌Panc-1细胞增殖的影响.方法:设计4组靶向HIF-1α和Survivin基因的寡核苷酸序列,连接至pcDNA6.2-GW/EmGFP-miR质粒,构建两组共8个载体,依次为anti-H(Ⅰ)、anti-H(Ⅱ)、anti-H(Ⅲ)、anti-H(Ⅳ)和anti-S(Ⅰ)、anti-S(Ⅱ)、anti-S(Ⅲ)、anti-S(Ⅳ).实时定量RT-PCR检测靶基因mRNA的表达水平,将两组中mRNA下调作用最强的质粒串联,构建anti-H+S.用anti-H+S及mRNA下调作用最强的anti-H和anti-S转染胰腺癌Panc-1细胞,Western blot测定靶蛋白表达情况,MTT法检测细胞增殖活性.结果:经测序鉴定,所有anti-H、anti-S及双靶位质粒anti-H+S装载位点核苷酸序列与设计序列完全相符.anti-H的靶基因mRNA沉默效率依次为48%、2%、44%和30%;anti-S的靶基因mRNA沉默效率依次为72%、75%、58%和59%.由anti-H(Ⅰ)和anti-S(Ⅱ)串联得到双靶位质粒anti-H+S.anti-H+S的靶基因mRNA沉默效率为53% (HIF-1α)和42%(survivin).anti-H(Ⅰ)、anti-S(Ⅱ)及anti-H+S与对照质粒相比均使靶基因蛋白的表达明显下降,细胞增殖受到明显抑制(P<0.05).其中anti-H+S对细胞的增殖抑制作用强于anti-H(Ⅰ)和anti-S(Ⅱ),72h后差异有统计学意义(P<0.05).结论:本研究成功构建了抗HIF-1α和Survivin的单靶位质粒和双靶位质粒;其中,anti-H+S抑制胰腺癌Panc-1细胞增殖作用强于anti-H(Ⅰ)和anti-S(Ⅱ).%Objective:To design and construct miRNA expression vector dual-targeting on HIF-1αand survivin genes and to investigate its effects on proliferation of human pancreatic cancer cells. Methods; The specific pre-miRNA single strand DNA oligos for HIF-1α and survivin genes were designed and synthesized,then via annealing and ligating with pcDNA6. 2-GW/EmGFP-miR plasmids in order,two kinds (eight in total) of miRNA

  16. RNAi沉默Fas受体表达的腺病毒载体构建%Construction of Recombinant Adenovirus Vector expressing Two Fas-Targeted shRNA

    Institute of Scientific and Technical Information of China (English)

    刘明社; 赵中夫; 王兰; 张国英; 张芸; 封江南

    2006-01-01

    目的:利用pEGFP6-1和pGenesil-1质粒构建针对小鼠Fas的2个短发卡状RNA (short hairpin RNA,shRNA) 串联表达的载体pEGFP6-1-siFas1+siFas2,进一步通过BD Adeno-X系统构建腺病毒表达Fas-shRNA载体.方法:设计表达2个短发卡状RNA结构的互补DNA序列分别克隆至质粒载体pEGFP6-1和pGenesil-1中,酶切pEGFP6-1-siFas1大片段和酶切pGenesil-1-siFas2小片段,经T4 DNA Ligase连接得到pEGFP6-1-siFas1+siFas2重组质粒.双酶切重组质粒和pShuttle2穿梭质粒,经T4 DNA连接酶连接得到pShuttle2-siFas1+siFas2质粒.双酶切重组穿梭质粒,连接酶切产物和腺病毒转化感受态E.coil DH5а,PCR筛选鉴定阳性克隆,进一步线性化重组腺病毒pAdeno-siFas1+siFas2质粒,经脂质体转染HEK 293A细胞;收细胞进行裂解收病毒. 结果:构建的重组质粒载体经酶切鉴定和测序分析,shRNA编码序列与设计的片段完全一致;重组腺病毒载体经酶切鉴定和PCR分析正确;经HEK293A细胞包装成功,能够表达绿色荧光蛋白.结论:成功构建Fas-shRNA腺病毒串联表达载体.

  17. 猪CART mRNA全CDS区序列的克隆与表达载体的构建%Cloning of the sequence of CDS region of pig CART mRNA and construction of the expression vector

    Institute of Scientific and Technical Information of China (English)

    李鹏飞; 李富禄; 于秀菊; 吕丽华

    2011-01-01

    选用猪为研究对象,以可卡因苯异丙胺调控转录肽(CART)作为影响猪繁殖机能的多肽,依据NCBI上登录的CARTmRNA序列设计3对特异性引物,用RT-PCR方法从下丘脑内扩增出CART mRNA的部分序列并进行序列分析;再根据扩增出的序列设计一对带酶切位点的特异性引物,用PCR方法扩增出含EcoR Ⅰ/HindⅢ酶切位点的CART mRNA的全编码序列(CDS)区序列.结果表明:猪下丘脑CART mRNA的CDS区全长367 bp,CART基因在下丘脑上有表达,并成功构建pEG-32a-CART原核表达载体.%Designing three pain specific primers based on the CART mRNA sequence included in NCBI GenBank, CART tnRNA sequences were amplified via RT-PCR from porcine hypothalamus tissue, and were analyzed. According to the amplified sequence, we designed a pair of expressing primers, amplified the whole coding sequence ( CDS) domain of CART including EcoR Ⅰ/Hind Ⅲ digestion sites. The results showed that; the length of CDS in porcine hypothalamus CART mRNA is 367 bp, CART gene can express in the hypothalamus, and it had successfully constructed prokaryotic expression vector of pEG-32a-CART.

  18. Construction and identification of lentiviral vector containing human ILK-shRNA and mda7 gene%整合素连接激酶基因敲降和黑色素瘤分化相关基因过表达慢病毒载体构建和鉴定

    Institute of Scientific and Technical Information of China (English)

    杨幼萍; 应荣彪; 丁燕; 王继荣; 曾玲晖; 林红霞; 朱杨丽; 吴宏卫; 王若燕; 张建民

    2014-01-01

    目的:建立整合素相关激酶( ILK)基因敲降和黑色素瘤分化相关基因( mda7)过表达慢病毒包装表达系统。方法:针对人ILK基因序列,设计基因敲降靶点序列(A、B、C),通过限制性内切酶HpaⅠ和XhoⅠ双酶切、T4 DNA连接酶连接,将ILK插入慢病毒载体pSicoR-eGFP,构建siILK-pSicoR-eGFP重组质粒;根据人mda7基因序列,设计引物扩增mda7全长,并插入慢病毒载体pLVX-Puro,构建mda7-pLVX-Puro重组质粒。经双酶切及测序鉴定正确后通过脂质体将慢病毒四质粒系统共转染人胚肾细胞系293 T细胞,进行慢病毒包装并测定病毒滴度、观察感染效率。各组病毒载体转染PC-3细胞后,用定量PCR和蛋白质印迹法检测ILK基因和mda7 mRNA转录水平及蛋白表达水平。通过MTT法和Transwell实验考察ILK和mda7对PC-3细胞增殖和迁移的影响。结果:成功构建ILK基因敲降及mda7过表达的慢病毒载体,四质粒系统共转染293 T细胞后可见大量绿色荧光染色阳性细胞。浓缩病毒后293 T细胞的感染效率在90%以上,并能高效率感染PC-3前列腺癌细胞。 ILK-A-pSicoR-eGFP和ILK-B-pSicoR-eGFP组ILK干扰效果最佳(P<0.05),mda7的表达水平远高于对照组(P<0.05),且持续稳定表达至少1个月。 ILK和mda7对PC-3细胞的增殖在96 h内有明显抑制作用,并对其迁移亦有显著抑制(均P<0.05)。结论:成功构建并鉴定人ILK 基因敲降和mda7过表达慢病毒载体,可为探讨ILK和mda7基因在肿瘤细胞中的生物学功能提供良好工具,也为探索安全、高效的肿瘤治疗途径奠定实验基础。%Objective: To construct and identify lentiviral vector containing human ILK-shRNA and mda7 gene.Methods:Based on the human ILK gene sequences , RNAi target sequences were designed and cloned into the lentiviral vector pSicoR -eGFP by restriction endonuclease HpaⅠand Xho

  19. RNA Origami

    DEFF Research Database (Denmark)

    Sparvath, Steffen Lynge

    2017-01-01

    for biosensorer,  der kan spore enten microRNA’er eller små molekyler, eksemplificeret ved S-adenosylmethionin (SAM). Slutteligt indikerer foreløbige resultater, at apta-FRET SAM sensoren kan udtrykkes i Escherichia coli-celler, hvilket viser, at RNA-origami arkitekturen muliggør cotransskriptionel foldning af......RNA-nanoteknologi feltet har demonstreret alsidigheden af RNA som byggemateriale, og rationelt designede RNA-nanostrukturer er blevet brugt i udviklingen af strukturelle platforme og dynamiske anordninger med anvendelser både in vitro og in vivo. Naturlige RNA-strukturer foldes cotransskriptionelt...... fra en enkelt RNA-streng, og udfører en lang række komplekse cellulære funktioner. Mange af funktionerne er blevet udnyttet til at skabe funktionelle RNA-baserede nanoapparater, men den nuværende litteratur giver kun få eksempler på cotranskriptionel produktion af RNA-nanostrukturer. I 2014...

  20. RNA granules

    OpenAIRE

    Anderson, Paul; Kedersha, Nancy

    2006-01-01

    Cytoplasmic RNA granules in germ cells (polar and germinal granules), somatic cells (stress granules and processing bodies), and neurons (neuronal granules) have emerged as important players in the posttranscriptional regulation of gene expression. RNA granules contain various ribosomal subunits, translation factors, decay enzymes, helicases, scaffold proteins, and RNA-binding proteins, and they control the localization, stability, and translation of their RNA cargo. We review the relationshi...

  1. 靶向Ang2的RNAi慢病毒载体的构建及其对恶性黑色素瘤细胞中Ang2基因表达的影响%Construction of Recombinant Lentiviral Vector of siRNA for Ang2 and the Effect of the Expression of Ang2 Gene in Malignant Melanoma Cells

    Institute of Scientific and Technical Information of China (English)

    刘照亮; 王彪; 郭国祥; 单秀英; 王美水; 庄福连; 蔡传书; 张明凤; 张彦定

    2011-01-01

    vector systems of three plasmids were constituted using pNL-EGFP-U6-Ang2- I ( pNL-EGFP-U6-Ang2- Ⅱ ), pVSVG and pHelper. The lentiviral vector system was transfected into 293T cell to produce pNL-EGFP-U6-Ang2- I and pNL-EGFP-U6-Ang2- Ⅱ lentivirus. Supernatant was collected to determine the titer. Malignant melanoma cells were transduced with both lentiviruses. Realtime RT-PCR was conducted to examine inhibitory efficiency. Results The recombinant lentiviral vectors of Ang2-RNAi were constructed successfully, as confirmed by restriction enzyme digestion and sequencing. Lentiviral titer was up to 8. 0 x l03/ml. Real-time RT-PCR demonstrated that the lentiviral vectors of Ang2-RNAi infect malignant melanoma cells and inhibit the expression of Ang2 genes in malignant melanoma cells ( P < 0. 05 ) . Conclusion Lentivector carrying Ang2-siRNA was constructed successfully and it was able to inhibit the expression of Ang2 gene in vitro significantly. The study established preliminary research on the inhibition of the growth of malignant melanoma xenografts in nude mice and provides the experimental evidence for tumor gene therapy in future.

  2. RNA interference of influenza A virus replication by microRNA-adapted lentiviral loop short hairpin RNA.

    Science.gov (United States)

    Xu, Fang; Liu, Guanqun; Liu, Qiang; Zhou, Yan

    2015-10-01

    Limitations of the current vaccines and antivirals against influenza A virus (IAV) pandemic underscore the urgent need for developing novel anti-influenza strategies. RNA interference (RNAi) induced by small interfering RNA (siRNA) has become a powerful new means to inhibit viral infection in a gene-specific manner. However, the efficacy of the siRNA delivery platform and the relatively high cost of administration have hindered widespread application of siRNA. In this study, we developed a microRNA (miRNA)-30-based lentivirus delivery system by embedding a synthetic short hairpin RNA (shRNA) stem into the context of endogenous precursor of miRNA-30 (shRNAmir) to express a silencer of the influenza gene. We showed that the miRNA-based lentivirus vector was able to express and process a single nucleoprotein (NP)-targeting shRNAmir, which could potently inhibit IAV replication. We further showed that miRNA-based lentivirus vector carrying tandemly linked NP and polymerase PB1 shRNAmirs could express and process double shRNAmirs. Despite the relatively low levels of NP and PB1 miRNAs produced in the stably transduced cells, the combination of two miRNAs exerted a great degree of inhibition on influenza infection. Given the advantage of combinatorial RNAi in preventing emergence of mutant virus, miRNA-based lentiviral vectors are valuable tools for anitiviral activities. To the best of our knowledge, this is the first study demonstrating that a miRNA-based RNAi strategy can be applied for better control of influenza virus infection.

  3. RNA genetics

    Energy Technology Data Exchange (ETDEWEB)

    Domingo, E. (Instituto de Biologia Molecular, Facultad de Ciencias, Universidad Autonoma de Madrid, Canto Blanco, Madrid (ES)); Holland, J.J. (California Univ., San Diego, La Jolla, CA (USA). Dept. of Biology); Ahlquist, P. (Wisconsin Univ., Madison, WI (USA). Dept. of Plant Pathology)

    1988-01-01

    This book contains the proceedings on RNA genetics: RNA-directed virus replication Volume 1. Topics covered include: Replication of the poliovirus genome; Influenza viral RNA transcription and replication; and Relication of the reoviridal: Information derived from gene cloning and expression.

  4. ON VECTOR NETWORK EQUILIBRIUM PROBLEMS

    Institute of Scientific and Technical Information of China (English)

    Guangya CHEN

    2005-01-01

    In this paper we define a concept of weak equilibrium for vector network equilibrium problems.We obtain sufficient conditions of weak equilibrium points and establish relation with vector network equilibrium problems and vector variational inequalities.

  5. RNA epigenetics

    OpenAIRE

    Liu, Nian; Pan, Tao

    2014-01-01

    Mammalian messenger and long non-coding RNA contain tens of thousands of post-transcriptional chemical modifications. Among these, the N6-methyl-adenosine (m6A) modification is the most abundant and can be removed by specific mammalian enzymes. M6A modification is recognized by families of RNA binding proteins that affect many aspects of mRNA function. mRNA/lncRNA modification represents another layer of epigenetic regulation of gene expression, analogous to DNA methylation and histone modifi...

  6. An method for small hairpin RNA expression vector reconstruction for easy single restriction endonuclease identification%一种方便酶切鉴定的shRNA表达载体改建方法

    Institute of Scientific and Technical Information of China (English)

    单志新; 林秋雄; 符永恒; 邓春玉; 余细勇

    2007-01-01

    目的 建立一种用单限制性内切酶酶切来快速筛选重组小发夹RNA(shRNA)表达载体的方法.方法 制备包含单一限制性内切酶Cta Ⅰ识别序列的双链DNA插入片段(Cla Ⅰ位点两侧碱基序列不互补).与BamH Ⅰ和Hind Ⅲ线性化的shRNA表达载体pSilencer-4.1(不含Cla Ⅰ识别序列)构建载体pSilencer-4.1-Cla Ⅰ.用BamH Ⅰ和Hind Ⅲ酶切pSilencer-4.1-Cla Ⅰ,将酶切产物与表达绿色荧光蛋白(GFP)shRNA的DNA模板(不含Cla Ⅰ识别序列)做连接反应.构建GFP shRNA表达质粒.提取阳性克隆质粒DNA,行Cla Ⅰ单酶切鉴定,对未被Cla Ⅰ线性化的质粒行DNA测序鉴定.结果 DNA测序表明正确构建了shRNA表达载体pSilencer-4.1-Cla Ⅰ,以pSilencer-4.1-Cla Ⅰ为载体构建的GFPshRNA候选重组子中,不能被Cla Ⅰ线性化的均为GFP shRNA表达质粒.结论 构建了可用于制备shRNA表达质粒的通用载体pSilencer-4.1-Cla Ⅰ,所引入的单一的Cla Ⅰ识别位点可以用来快速地筛选重组shRNA表达质粒.

  7. Light composite vector bosons

    CERN Document Server

    Kosower, David A.

    1993-01-01

    In gauge theories with slowly-running coupling constants, it may be possible for four-fermion operators to be nearly marginal. Such operators can possess asymptotically weak couplings, and can plausibly give rise to light composite vector mesons.

  8. GAP Land Cover - Vector

    Data.gov (United States)

    Minnesota Department of Natural Resources — This vector dataset is a detailed (1-acre minimum), hierarchically organized vegetation cover map produced by computer classification of combined two-season pairs of...

  9. Tagged Vector Contour (TVC)

    Data.gov (United States)

    Kansas Data Access and Support Center — The Kansas Tagged Vector Contour (TVC) dataset consists of digitized contours from the 7.5 minute topographic quadrangle maps. Coverage for the state is incomplete....

  10. A Modified Replicon Expression Vector Derived from RNA Replicon of Semliki Forest Virus%一种基于塞姆利基森林病毒复制子的新型复制子载体

    Institute of Scientific and Technical Information of China (English)

    仇华吉; 罗玉子; 李娜; 童光志

    2004-01-01

    RNA复制子是能自主复制的病毒RNA.基于RNA复制子的表达载体和基因疫苗比常规真核表达载体和DNA疫苗具有更大的优越性.以塞姆利基森林病毒RNA复制子衍生的真核表达载体pSFV1为骨架,插入CMV立即早期启动子和SV40晚期Poly(A)信号,构建了一种完全基于DNA的复制型表达载体pSFV1CS,将增强型绿色荧光蛋白基因EGFP插入其中,构建了重组质粒pSFV1CS-EGFP,通过转染293T细胞,证实外源基因能在其中高效表达.该载体可用于表达真核蛋白和构建复制子载体疫苗.

  11. [Agrobacterium-mediated sunflower transformation (Helianthus annuus L.) in vitro and in Planta using strain of LBA4404 harboring binary vector pBi2E with dsRNA-suppressor proline dehydrogenase gene].

    Science.gov (United States)

    Tishchenko, E N; Komisarenko, A G; Mikhal'skaia, S I; Sergeeva, L E; Adamenko, N I; Morgun, B V; Kochetov, A V

    2014-01-01

    To estimate the efficiency of proline dehydrogenase gene suppression towards increasing of sunflower (Helianthus annuus L.) tolerance level to water deficit and salinity, we employed strain LBA4404 harboring pBi2E with double-stranded RNA-suppressor, which were prepared on basis arabidopsis ProDH1 gene. The techniques of Agrobacterium-mediated transformation in vitro and in planta during fertilization sunflower have been proposed. There was shown the genotype-depended integration of T-DNA in sunflower genome. PCR-analysis showed that ProDH1 presents in genome of inbred lines transformed in planta, as well as in T1- and T2-generations. In trans-genic regenerants the essential accumulation of free L-proline during early stages of in vitro cultivation under normal conditions was shown. There was established the essential accumulation of free proline in transgenic regenerants during cultivation under lethal stress pressure (0.4 M mannitol and 2.0% sea water salts) and its decline upon the recovery period. These data are declared about effectiveness of suppression of sunflower ProDH and gene participation in processes connected with osmotolerance.

  12. Vector Lattice Vortex Solitons

    Institute of Scientific and Technical Information of China (English)

    WANG Jian-Dong; YE Fang-Wei; DONG Liang-Wei; LI Yong-Ping

    2005-01-01

    @@ Two-dimensional vector vortex solitons in harmonic optical lattices are investigated. The stability properties of such solitons are closely connected to the lattice depth Vo. For small Vo, vector vortex solitons with the total zero-angular momentum are more stable than those with the total nonzero-angular momentum, while for large Vo, this case is inversed. If Vo is large enough, both the types of such solitons are stable.

  13. Support vector machines applications

    CERN Document Server

    Guo, Guodong

    2014-01-01

    Support vector machines (SVM) have both a solid mathematical background and good performance in practical applications. This book focuses on the recent advances and applications of the SVM in different areas, such as image processing, medical practice, computer vision, pattern recognition, machine learning, applied statistics, business intelligence, and artificial intelligence. The aim of this book is to create a comprehensive source on support vector machine applications, especially some recent advances.

  14. The Vector Curvaton

    CERN Document Server

    Navarro, Andres A

    2013-01-01

    We analyze a massive vector field with a non-canonical kinetic term in the action, minimally coupled to gravity, where the mass and kinetic function of the vector field vary as functions of time during inflation. The vector field is introduced following the same idea of a scalar curvaton, which must not affect the inflationary dynamics since its energy density during inflation is negligible compared to the total energy density in the Universe. Using this hypothesis, the vector curvaton will be solely responsible for generating the primordial curvature perturbation \\zeta. We have found that the spectra of the vector field perturbations are scale-invariant in superhorizon scales due to the suitable choice of the time dependence of the kinetic function and the effective mass during inflation. The preferred direction, generated by the vector field, makes the spectrum of \\zeta depend on the wavevector, i.e. there exists statistical anisotropy in \\zeta. This is discussed principally in the case where the mass of th...

  15. Nonviral Vectors for Gene Delivery

    Science.gov (United States)

    Baoum, Abdulgader Ahmed

    2011-12-01

    The development of nonviral vectors for safe and efficient gene delivery has been gaining considerable attention recently. An ideal nonviral vector must protect the gene against degradation by nuclease in the extracellular matrix, internalize the plasma membrane, escape from the endosomal compartment, unpackage the gene at some point and have no detrimental effects. In comparison to viruses, nonviral vectors are relatively easy to synthesize, less immunogenic, low in cost, and have no limitation in the size of a gene that can be delivered. Significant progress has been made in the basic science and applications of various nonviral gene delivery vectors; however, the majority of nonviral approaches are still inefficient and often toxic. To this end, two nonviral gene delivery systems using either biodegradable poly(D,L-lactide- co-glycolide) (PLG) nanoparticles or cell penetrating peptide (CPP) complexes have been designed and studied using A549 human lung epithelial cells. PLG nanoparticles were optimized for gene delivery by varying particle surface chemistry using different coating materials that adsorb to the particle surface during formation. A variety of cationic coating materials were studied and compared to more conventional surfactants used for PLG nanoparticle fabrication. Nanoparticles (˜200 nm) efficiently encapsulated plasmids encoding for luciferase (80-90%) and slowly released the same for two weeks. After a delay, moderate levels of gene expression appeared at day 5 for certain positively charged PLG particles and gene expression was maintained for at least two weeks. In contrast, gene expression mediated by polyethyleneimine (PEI) ended at day 5. PLG particles were also significantly less cytotoxic than PEI suggesting the use of these vehicles for localized, sustained gene delivery to the pulmonary epithelium. On the other hand, a more simple method to synthesize 50-200 nm complexes capable of high transfection efficiency or high gene knockdown was

  16. RNA疫苗%RNA vaccines

    Institute of Scientific and Technical Information of China (English)

    吴浩飞; 罗丹

    2013-01-01

    Nucleic acid vaccines consist of plasmid DNA,viral vectors and RNA vaccines.Since the nucleic acid vaccines combine the benefits of live-attenuated vaccines,and avoid the problems of complication related to live-attenuated vaccine safety and production,they may change the way that next generation vaccines are produced.RNA vaccines,including those based on messenger RNA (mRNA) and self-amplifying RNA replicons,have the potential to break through the limitations of plasmid DNA and viral vectors.With solving the issue of cost and manufacturing feasibility,the commercialization of RNA vaccines has become promising.The concept of RNA vaccines has been demonstrated in humans,and the prospects for further development into commercial products are very encouraging.%核酸疫苗包括质粒DNA、病毒载体和RNA疫苗,极有可能促成新一代疫苗生产方式的变革,因为它既综合了减毒活疫苗的优势,又避免了减毒活疫苗的安全性及生产复杂性等问题.RNA疫苗,包括基于信使RNA(mRNA)和自我扩增RNA复制子的疫苗,能克服质粒DNA和病毒载体的局限性.随着RNA疫苗的生产可行性及成本问题的解决,RNA疫苗商业化的曙光已经显现.RNA疫苗概念在人体中已得到验证,其进一步开发为商业化产品的前景令人鼓舞.

  17. Use of human MAR elements to improve retroviral vector production.

    Science.gov (United States)

    Buceta, M; Galbete, J L; Kostic, C; Arsenijevic, Y; Mermod, N

    2011-01-01

    Retroviral vectors have many favorable properties for gene therapies, but their use remains limited by safety concerns and/or by relatively lower titers for some of the safer self-inactivating (SIN) derivatives. In this study, we evaluated whether increased production of SIN retroviral vectors can be achieved from the use of matrix attachment region (MAR) epigenetic regulators. Two MAR elements of human origin were found to increase and to stabilize the expression of the green fluorescent protein transgene in stably transfected HEK-293 packaging cells. Introduction of one of these MAR elements in retroviral vector-producing plasmids yielded higher expression of the viral vector RNA. Consistently, viral titers obtained from transient transfection of MAR-containing plasmids were increased up to sixfold as compared with the parental construct, when evaluated in different packaging cell systems and transfection conditions. Thus, use of MAR elements opens new perspectives for the efficient generation of gene therapy vectors.

  18. Vector cross product in n-dimensional vector space

    OpenAIRE

    Tian, Xiu-Lao; Yang, Chao; Hu, Yang; Tian, Chao

    2013-01-01

    The definition of vector cross product (VCP) introduced by Eckmann only exists in thethree- and the seven- dimensional vector space. In this paper, according to the orthogonal completeness, magnitude of basis vector cross product and all kinds of combinations of basis vector $\\hat{e}_i$, the generalized definition of VCP in the odd n-dimensional vector space is given by introducing a cross term $X_{AB}$. In addition, the definition is validated by reducing the generalization definition to the...

  19. RNA oxidation

    DEFF Research Database (Denmark)

    Kjaer, L. K.; Cejvanovic, V.; Henriken, T.

    2015-01-01

    in diabetes resulting from the diabetic state, a dysfunction that includes increased production of hydrogen peroxide. We suggest that the intracellular RNA oxidation is compartmentalized from the traditional biomarkers in the extracellular compartment, and therefore provides independent prognostic value...... diabetes. In agreement with our previous finding, DNA oxidation did not show any prognostic value. RNA oxidation represents oxidative stress intracellularly, presumably predominantly in the cytosol. The mechanism of RNA oxidation is not clear, but hypothesized to result from mitochondrial dysfunction...

  20. Construction of eukaryotic expression vectors of siRNA against TNF-α gene and their silencing effects on TNF-α and TGF-β1 in A549 cells%TNF-α基因siRNA真核表达载体的构建及其对A549细胞TNF-α和TGF-β1表达的影响

    Institute of Scientific and Technical Information of China (English)

    张立英; 刘绍霞; 赵国强; 张国俊

    2012-01-01

    目的:构建靶向肿瘤坏死因子α(TNF-α)基因的小干扰RNA(siRNA)真核表达载体,观察其对人肺腺癌A549细胞中TNF-α和转化生长因子-β1(TGF-β1)表达的影响.方法:依据GenBank中人TNF-α(NM_000594)序列和siRNA靶序列设计原则,设计并合成一对针对TNF-α的特异性序列(siTNF-α)和一对无关序列(siCon).退火合成DNA双链,再分别重组入pRNAT-U6.1载体,经过PCR和DNA测序鉴定.将构建好的重组载体pRNAT-U6.1-siTNF-α、pRNAT-U6.1-siCon及空载体pRNAT-U6.1用脂质体介导转染A549细胞株,分别采用Real time PCR和Western blot方法检测细胞中TNF-α和TGF-β1 mRNA和蛋白的表达水平.结果:PCR和DNA测序鉴定证实载体构建成功;转染pRNAT-U6.1-siTNF-α的A549细胞中TNF-α和TGF-β1 mRNA和蛋白表达水平均低于其他3组(FmRNA=478.663,4.081;F蛋白=123.420,6.312,P均<0.05).结论:成功构建了靶向TNF-α基因的siRNA真核表达载体,该载体能够有效沉默A549细胞中TNF-α的表达,TGF-β1基因表达亦受到抑制.%Aim: To clone the eukaryotic expression vectors of small interfering RNA ( siRNA ) against TNF-a gene and to evaluate their silencing effects on TNF-a and TGF-β1 in A549 cells. Methods: According to TNF-a gene ( NM_ 000594 ) sequence of GenBank, using RNAi Designer software to design the siRNA specific target sequence ( siTNF-α ) and the unrelated control sequence ( siCon ) for TNF-α. The annealing products were recombined into pRNAT-U6. 1, PCR and DNA sequencing confirmed the insertion sequence. The recombinant plasmids ( pRNAT-U6. l-siTNF-a,pRNAT-U6. 1-siCon ) were transfected to the A549 cells with lipofectamine,and the expressions of TNF-α, TGF-β1 mRNA and protein in cells detected by Real time PCR and Western blot methods. Results: PCR and DNA sequencing confirmed the vectors were consistent;the expressions of TNF-α, TGF-β1 mRNA and protein in the cells transfected pRNAT-U6. 1-siTNF-a were markedly lower than the other three

  1. Construction of RNA Interfering Lentivirus Vector Targeting Uncoupling Protein 2%解偶联蛋白-2RNA干扰慢病毒载体的构建

    Institute of Scientific and Technical Information of China (English)

    万赤丹; 程锐; 王春友; 王宏博; 王帅; 刘涛

    2008-01-01

    目的:构建解偶联蛋白-2(UCP-2)基因的RNA干扰慢病毒载体.方法:根据RNA干扰序列设计原则,针对UCP-2mRNA(NM_011671)设计3个RNA干扰靶点序列,合成含干扰序列的DNA双链,酶切后连入慢病毒转移质粒pGCL-GFP中.连接产物转化感受态细胞,所获克隆行PCR鉴定和序列测定.构建成功的RNA干扰质粒与UCP-2表达质粒共转染293T细胞,荧光显微镜下观测转染效果,Western blot检测UCP-2蛋白表达,筛选出干扰效果最好RNA干扰质粒.将该质粒与两种辅助包装原件载体质粒pHelper 1.0(gag/pol元件)载体,Helper 2.0(VSVG元件)共转染293T细胞包装成慢病毒并检测滴度.结果:PCR和测序结果显示针对3个靶点的RNA干扰质粒均构建成功;通过Western blot检测获得最优干扰靶点,并成功包装成滴度为5×108TU/ml的慢病毒.结论:成功构建可供感染的解偶联蛋白-2 RNA干扰慢病毒载体,为后续靶向抑制该基因表达以提高脂肪肝移植成功率的研究莫定物质基础.

  2. Construction of TLR4 gene-specific RNA interference recombinant vectors and comparison on their silence effects%TLR4基因RNA干扰载体的构建及其抑制效率比较

    Institute of Scientific and Technical Information of China (English)

    姜泓; 王平忠; 张野; 徐哲; 王九平; 彭梅娟; 黄长形; 白雪帆

    2009-01-01

    目的 构建含有Toll样受体4(TLR4)基因特异性RNA干扰序列的pSliencer4.1-CMV neo载体,比较其对TLR4的抑制效率.方法 通过Ambion公司的在线软件设计TLR4基因(GenBank:NM138554)的RNA干扰(RNAi)序列,按siRNA设计的优化原则筛选靶序列,再选取其中部分序列进行合成,经退火、连接,构建含有TLR4基因特异性RNA干扰序列的pSliencer4.1-CMVneo载体.用脂质体SPort XP-1分别将载体及阳性和阴性对照质粒转染血管内皮细胞系EVC-304细胞,提取细胞总RNA,进行RT-PCR反应,筛选抑制效率较高的载体.结果 共设计出可供选择的序列228条,经BLAST比对后,有30条序列有较好的序列特异性,并根据其在基因中的相对位置选择9条作为siRNA靶序列.RT-PCR结果表明其中有5个载体具有较高的抑制效率,以TS4,TS6,TS8抑制效率最高,分别为89%,90%,88%,其余siRNA的抑制效率均未超过50%.抑制效果较好的5条序列在TLR4基因中的位置分别为444、1 203、1 389、2 774、3 409nt处.结论 成功构建了抑制效率较高的TLR4基因特异性RNA干扰序列的pSliencer4.1-CMV neo载体,筛选出特异性抑制TLR4表达的序列,为TLR4信号转导的研究奠定了基础.

  3. Extended Mixed Vector Equilibrium Problems

    Directory of Open Access Journals (Sweden)

    Mijanur Rahaman

    2014-01-01

    Full Text Available We study extended mixed vector equilibrium problems, namely, extended weak mixed vector equilibrium problem and extended strong mixed vector equilibrium problem in Hausdorff topological vector spaces. Using generalized KKM-Fan theorem (Ben-El-Mechaiekh et al.; 2005, some existence results for both problems are proved in noncompact domain.

  4. Scalable motion vector coding

    Science.gov (United States)

    Barbarien, Joeri; Munteanu, Adrian; Verdicchio, Fabio; Andreopoulos, Yiannis; Cornelis, Jan P.; Schelkens, Peter

    2004-11-01

    Modern video coding applications require transmission of video data over variable-bandwidth channels to a variety of terminals with different screen resolutions and available computational power. Scalable video coding is needed to optimally support these applications. Recently proposed wavelet-based video codecs employing spatial domain motion compensated temporal filtering (SDMCTF) provide quality, resolution and frame-rate scalability while delivering compression performance comparable to that of the state-of-the-art non-scalable H.264-codec. These codecs require scalable coding of the motion vectors in order to support a large range of bit-rates with optimal compression efficiency. Scalable motion vector coding algorithms based on the integer wavelet transform followed by embedded coding of the wavelet coefficients were recently proposed. In this paper, a new and fundamentally different scalable motion vector codec (MVC) using median-based motion vector prediction is proposed. Extensive experimental results demonstrate that the proposed MVC systematically outperforms the wavelet-based state-of-the-art solutions. To be able to take advantage of the proposed scalable MVC, a rate allocation mechanism capable of optimally dividing the available rate among texture and motion information is required. Two rate allocation strategies are proposed and compared. The proposed MVC and rate allocation schemes are incorporated into an SDMCTF-based video codec and the benefits of scalable motion vector coding are experimentally demonstrated.

  5. Vector Fields on Product Manifolds

    CERN Document Server

    Kurz, Stefan

    2011-01-01

    This short report establishes some basic properties of smooth vector fields on product manifolds. The main results are: (i) On a product manifold there always exists a direct sum decomposition into horizontal and vertical vector fields. (ii) Horizontal and vertical vector fields are naturally isomorphic to smooth families of vector fields defined on the factors. Vector fields are regarded as derivations of the algebra of smooth functions.

  6. 携带ROCK2基因siRNA有效片段的慢病毒载体的筛选%Screening lentiviral vectors carrying effective siRNA of the ROCK2 gene

    Institute of Scientific and Technical Information of China (English)

    彭强; 马福年; 姜睿; 陈枫

    2014-01-01

    目的:筛选能够显著抑制自发性高血压大鼠(SHR)阴茎海绵体平滑肌细胞内ROCK2基因表达的携带ROCK2基因siRNA的慢病毒载体. 方法:设计并合成4个靶向ROCK2的siRNA片段,构建并包装成慢病毒载体.随机将5只SHR阴茎海绵体平滑肌细胞分为6组,每组每个样本3×104个细胞,每组5个样本,分别为:A组(未转染对照组)、B组(携带慢病毒转染组)、C~F组(分别携带靶向ROCK2基因siRNA 1~4号靶点的慢病毒转染组),以感染复(MOI)=80转染SHR阴茎海绵体平滑肌细胞,转染后48 h荧光显微镜下观察细胞GFP表达情况,并用RT-PCR检测各组被转染细胞ROCK2mRNA的表达. 结果:荧光显微镜下观察各组细胞转染效率均>50%.与A组相比,B组ROCK2mRNA的表达无明显改变(P>0.05);C、D、F组SHR阴茎海绵体平滑肌细胞ROCK2基因mRNA的表达较A组极显著下降(P<0.01),抑制效率分别达到(43.91 ±8.19)%、(47.15±6.64)%、(25.7±6.03)%;E组SHR阴茎海绵体平滑肌细胞ROCK2基因mRNA的表达较A组显著下降(P<0.05),抑制效率为(16.81 ±5.94)%. 结论:本研究构建的4种携带ROCK2基因的siRNA慢病毒载体均能够显著抑制SHR阴茎海绵体平滑肌细胞内ROCK2基因的表达,其中有1种慢病毒载体抑制作用最强.

  7. DDX3 DEAD-Box RNA Helicase Is Required for Hepatitis C Virus RNA Replication▿

    OpenAIRE

    2007-01-01

    DDX3, a DEAD-box RNA helicase, binds to the hepatitis C virus (HCV) core protein. However, the role(s) of DDX3 in HCV replication is still not understood. Here we demonstrate that the accumulation of both genome-length HCV RNA (HCV-O, genotype 1b) and its replicon RNA were significantly suppressed in HuH-7-derived cells expressing short hairpin RNA targeted to DDX3 by lentivirus vector transduction. As well, RNA replication of JFH1 (genotype 2a) and release of the core into the culture supern...

  8. Robustifying Vector Median Filter

    Directory of Open Access Journals (Sweden)

    Valentín Gregori

    2011-08-01

    Full Text Available This paper describes two methods for impulse noise reduction in colour images that outperform the vector median filter from the noise reduction capability point of view. Both methods work by determining first the vector median in a given filtering window. Then, the use of complimentary information from componentwise analysis allows to build robust outputs from more reliable components. The correlation among the colour channels is taken into account in the processing and, as a result, a more robust filter able to process colour images without introducing colour artifacts is obtained. Experimental results show that the images filtered with the proposed method contain less noisy pixels than those obtained through the vector median filter. Objective measures demonstrate the goodness of the achieved improvement.

  9. Boosting Support Vector Machines

    Directory of Open Access Journals (Sweden)

    Elkin Eduardo García Díaz

    2006-11-01

    Full Text Available En este artículo, se presenta un algoritmo de clasificación binaria basado en Support Vector Machines (Máquinas de Vectores de Soporte que combinado apropiadamente con técnicas de Boosting consigue un mejor desempeño en cuanto a tiempo de entrenamiento y conserva características similares de generalización con un modelo de igual complejidad pero de representación más compacta./ In this paper we present an algorithm of binary classification based on Support Vector Machines. It is combined with a modified Boosting algorithm. It run faster than the original SVM algorithm with a similar generalization error and equal complexity model but it has more compact representation.

  10. RNA. Introduction.

    Science.gov (United States)

    Bao, Marie Z; Kruger, Robert P; Rivas, Fabiola; Smith, Orla; Szewczak, Lara

    2009-02-20

    Two scientists walk into a bar. After a pint and an exchange of pleasantries, one says to the other, "Where do you come from? Scientifically, I mean." The queried scientist responds, "Out of the RNA world." "Don't we all," the asker responds chuckling. Fifteen years ago, the joke would have been made with a nod to the notion that life arose from an RNA-based precursor, the so-called "RNA world." Yet had this conversation happened last week, the scientists would also be grinning in appreciation of the extent to which contemporary cellular biology is steeped in all things RNA. Ours is truly an RNA world.In this year's special review issue, the Cell editorial team has brought together articles focused on RNA in the modern world, providing perspectives on classical and emerging areas of inquiry. We extend our thanks to the many distinguished experts who contributed their time and effort as authors and reviewers to make the issue informative, thought-provoking, and timely. We hope that this collection of articles, written as we stand on the verge of a new wave of RNA biology, edifies and inspires by revealing the inner workings of these versatile molecules and by highlighting the next key questions that need to be addressed as we strive to understand the full functional scope of RNA in cells.

  11. Scalar-Vector Bootstrap

    CERN Document Server

    Rejon-Barrera, Fernando

    2015-01-01

    We work out all of the details required for implementation of the conformal bootstrap program applied to the four-point function of two scalars and two vectors in an abstract conformal field theory in arbitrary dimension. This includes a review of which tensor structures make appearances, a construction of the projectors onto the required mixed symmetry representations, and a computation of the conformal blocks for all possible operators which can be exchanged. These blocks are presented as differential operators acting upon the previously known scalar conformal blocks. Finally, we set up the bootstrap equations which implement crossing symmetry. Special attention is given to the case of conserved vectors, where several simplifications occur.

  12. Scalar-vector bootstrap

    Energy Technology Data Exchange (ETDEWEB)

    Rejon-Barrera, Fernando [Institute for Theoretical Physics, University of Amsterdam,Science Park 904, Postbus 94485, 1090 GL, Amsterdam (Netherlands); Robbins, Daniel [Department of Physics, Texas A& M University,TAMU 4242, College Station, TX 77843 (United States)

    2016-01-22

    We work out all of the details required for implementation of the conformal bootstrap program applied to the four-point function of two scalars and two vectors in an abstract conformal field theory in arbitrary dimension. This includes a review of which tensor structures make appearances, a construction of the projectors onto the required mixed symmetry representations, and a computation of the conformal blocks for all possible operators which can be exchanged. These blocks are presented as differential operators acting upon the previously known scalar conformal blocks. Finally, we set up the bootstrap equations which implement crossing symmetry. Special attention is given to the case of conserved vectors, where several simplifications occur.

  13. Topological vector spaces

    CERN Document Server

    Narici, Lawrence

    2011-01-01

    BackgroundTopology Valuation Theory Algebra Linear Functionals Hyperplanes Measure Theory Normed SpacesCommutative Topological GroupsElementary ConsiderationsSeparation and Compactness Bases at 0 for Group Topologies Subgroups and Products Quotients S-Topologies Metrizability CompletenessCompleteness Function Groups Total BoundednessCompactness and Total Boundedness Uniform Continuity Extension of Uniformly Continuous Maps CompletionTopological Vector SpacesAbsorbent and Balanced Sets Convexity-AlgebraicBasic PropertiesConvexity-Topological Generating Vector Topologies A Non-Locally Convex Spa

  14. Matrix vector analysis

    CERN Document Server

    Eisenman, Richard L

    2005-01-01

    This outstanding text and reference applies matrix ideas to vector methods, using physical ideas to illustrate and motivate mathematical concepts but employing a mathematical continuity of development rather than a physical approach. The author, who taught at the U.S. Air Force Academy, dispenses with the artificial barrier between vectors and matrices--and more generally, between pure and applied mathematics.Motivated examples introduce each idea, with interpretations of physical, algebraic, and geometric contexts, in addition to generalizations to theorems that reflect the essential structur

  15. Free topological vector spaces

    OpenAIRE

    Gabriyelyan, Saak S.; Morris, Sidney A.

    2016-01-01

    We define and study the free topological vector space $\\mathbb{V}(X)$ over a Tychonoff space $X$. We prove that $\\mathbb{V}(X)$ is a $k_\\omega$-space if and only if $X$ is a $k_\\omega$-space. If $X$ is infinite, then $\\mathbb{V}(X)$ contains a closed vector subspace which is topologically isomorphic to $\\mathbb{V}(\\mathbb{N})$. It is proved that if $X$ is a $k$-space, then $\\mathbb{V}(X)$ is locally convex if and only if $X$ is discrete and countable. If $X$ is a metrizable space it is shown ...

  16. Duality in vector optimization

    CERN Document Server

    Bot, Radu Ioan

    2009-01-01

    This book presents fundamentals and comprehensive results regarding duality for scalar, vector and set-valued optimization problems in a general setting. After a preliminary chapter dedicated to convex analysis and minimality notions of sets with respect to partial orderings induced by convex cones a chapter on scalar conjugate duality follows. Then investigations on vector duality based on scalar conjugacy are made. Weak, strong and converse duality statements are delivered and connections to classical results from the literature are emphasized. One chapter is exclusively consecrated to the s

  17. Analysis in Vector Spaces

    CERN Document Server

    Akcoglu, Mustafa A; Ha, Dzung Minh

    2011-01-01

    A rigorous introduction to calculus in vector spaces The concepts and theorems of advanced calculus combined with related computational methods are essential to understanding nearly all areas of quantitative science. Analysis in Vector Spaces presents the central results of this classic subject through rigorous arguments, discussions, and examples. The book aims to cultivate not only knowledge of the major theoretical results, but also the geometric intuition needed for both mathematical problem-solving and modeling in the formal sciences. The authors begin with an outline of key concepts, ter

  18. Is TNF-a-targeted short hairpin RNA (shRNA) a novel potential therapeutic tool in psoriasis treatment?

    DEFF Research Database (Denmark)

    Stenderup, Karin; Jakobsen, Maria; Rosada, Cecilia

    2008-01-01

      TNF-α is a well known target in psoriasis treatment and biological treatments targeting TNF-a are already clinically used against psoriasis and psoriasis arthritis. Attention is however given to a novel therapeutic tool: RNA interference that controls gene silencing. This study investigates...... the efficiency of targeting TNF-a with specific short hairpin RNA (shRNA) and explores its potential in treating psoriasis. ShRNAs targeting human TNF-α mRNA were generated. Their efficiency in down-regulating TNF-a protein expression was evaluated using a Renilla luciferase screening-assay and a transient co......-transfection assay. The expression cassette encoding the most efficient TNF-a shRNA was inserted into a lentiviral vector, allowing proficient gene delivery. The lentiviral vector is integrated into the host genome and establishes life-long infection and persistent shRNA expression. The lentiviral vector expressing...

  19. Alphavirus vectors: applications for DNA vaccine production and gene expression.

    Science.gov (United States)

    Lundstrom, K

    2000-01-01

    Replication-deficient alphavirus vectors have been developed for efficient high-level transgene expression. The broad host range of alphaviruses has allowed infection of a wide variety of mammalian cell lines and primary cultures. Particularly, G protein-coupled receptors have been expressed at high levels and subjected to binding and functional studies. Expression in suspension cultures has greatly facilitated production of large quantities of recombinant proteins for structural studies. Injection of recombinant alphavirus vectors into rodent brain resulted in local reporter gene expression. Highly neuron-specific expression was obtained in hippocampal slice cultures in vivo. Additionally, preliminary studies in animal models suggest that alphavirus vectors can be attractive candidates for gene therapy applications. Traditionally alphavirus vectors, either attenuated strains or replication-deficient particles, have been used to elicit efficient immune responses in animals. Recently, the application of alphaviruses has been extended to naked nucleic acids. Injection of DNA as well as RNA vectors has demonstrated efficient antigen production. In many cases, protection against lethal challenges has been obtained after immunization with alphavirus particles or nucleic acid vectors. Alphavirus vectors can therefore be considered as potentially promising vectors for vaccine production.

  20. Estimation of vector velocity

    DEFF Research Database (Denmark)

    2000-01-01

    Using a pulsed ultrasound field, the two-dimensional velocity vector can be determined with the invention. The method uses a transversally modulated ultrasound field for probing the moving medium under investigation. A modified autocorrelation approach is used in the velocity estimation. The new...

  1. Vectors Point Toward Pisa

    Science.gov (United States)

    Dean, Richard A.

    1971-01-01

    The author shows that the set of all sequences in which each term is the sum of the two previous terms forms a vector space of dimension two. He uses this result to obtain the formula for the Fibonacci sequence and applies the same technique to other linear recursive relations. (MM)

  2. Support Vector Components Analysis

    NARCIS (Netherlands)

    van der Ree, Michiel; Roerdink, Johannes; Phillips, Christophe; Garraux, Gaetan; Salmon, Eric; Wiering, Marco

    2017-01-01

    In this paper we propose a novel method for learning a distance metric in the process of training Support Vector Machines (SVMs) with the radial basis function kernel. A transformation matrix is adapted in such a way that the SVM dual objective of a classification problem is optimized. By using a wi

  3. Synthetic Space Vector Modulation

    Science.gov (United States)

    2013-06-01

    Modulation RF Radio Frequency SVM Space Vector Modulation VCO Voltage Controlled Oscillator VSI Voltage Source Inverter xvi THIS PAGE...examining the literature, an NE566 voltage controlled oscillator ( VCO ) chip as seen in Figure 10 was used to design a circuit that produced the

  4. Production of lentiviral vectors

    Directory of Open Access Journals (Sweden)

    Otto-Wilhelm Merten

    2016-01-01

    Full Text Available Lentiviral vectors (LV have seen considerably increase in use as gene therapy vectors for the treatment of acquired and inherited diseases. This review presents the state of the art of the production of these vectors with particular emphasis on their large-scale production for clinical purposes. In contrast to oncoretroviral vectors, which are produced using stable producer cell lines, clinical-grade LV are in most of the cases produced by transient transfection of 293 or 293T cells grown in cell factories. However, more recent developments, also, tend to use hollow fiber reactor, suspension culture processes, and the implementation of stable producer cell lines. As is customary for the biotech industry, rather sophisticated downstream processing protocols have been established to remove any undesirable process-derived contaminant, such as plasmid or host cell DNA or host cell proteins. This review compares published large-scale production and purification processes of LV and presents their process performances. Furthermore, developments in the domain of stable cell lines and their way to the use of production vehicles of clinical material will be presented.

  5. Vector-borne Infections

    Centers for Disease Control (CDC) Podcasts

    2011-04-18

    This podcast discusses emerging vector-borne pathogens, their role as prominent contributors to emerging infectious diseases, how they're spread, and the ineffectiveness of mosquito control methods.  Created: 4/18/2011 by National Center for Emerging Zoonotic and Infectious Diseases (NCEZID).   Date Released: 4/27/2011.

  6. What is a vector?

    Science.gov (United States)

    Wilson, Anthony James; Morgan, Eric René; Booth, Mark; Norman, Rachel; Perkins, Sarah Elizabeth; Hauffe, Heidi Christine; Mideo, Nicole; Antonovics, Janis; McCallum, Hamish; Fenton, Andy

    2017-05-05

    Many important and rapidly emerging pathogens of humans, livestock and wildlife are 'vector-borne'. However, the term 'vector' has been applied to diverse agents in a broad range of epidemiological systems. In this perspective, we briefly review some common definitions, identify the strengths and weaknesses of each and consider the functional differences between vectors and other hosts from a range of ecological, evolutionary and public health perspectives. We then consider how the use of designations can afford insights into our understanding of epidemiological and evolutionary processes that are not otherwise apparent. We conclude that from a medical and veterinary perspective, a combination of the 'haematophagous arthropod' and 'mobility' definitions is most useful because it offers important insights into contact structure and control and emphasizes the opportunities for pathogen shifts among taxonomically similar species with similar feeding modes and internal environments. From a population dynamics and evolutionary perspective, we suggest that a combination of the 'micropredator' and 'sequential' definition is most appropriate because it captures the key aspects of transmission biology and fitness consequences for the pathogen and vector itself. However, we explicitly recognize that the value of a definition always depends on the research question under study.This article is part of the themed issue 'Opening the black box: re-examining the ecology and evolution of parasite transmission'. © 2017 The Authors.

  7. Calculus with vectors

    CERN Document Server

    Treiman, Jay S

    2014-01-01

    Calculus with Vectors grew out of a strong need for a beginning calculus textbook for undergraduates who intend to pursue careers in STEM. fields. The approach introduces vector-valued functions from the start, emphasizing the connections between one-variable and multi-variable calculus. The text includes early vectors and early transcendentals and includes a rigorous but informal approach to vectors. Examples and focused applications are well presented along with an abundance of motivating exercises. All three-dimensional graphs have rotatable versions included as extra source materials and may be freely downloaded and manipulated with Maple Player; a free Maple Player App is available for the iPad on iTunes. The approaches taken to topics such as the derivation of the derivatives of sine and cosine, the approach to limits, and the use of "tables" of integration have been modified from the standards seen in other textbooks in order to maximize the ease with which students may comprehend the material. Additio...

  8. Estimation of vector velocity

    DEFF Research Database (Denmark)

    2000-01-01

    Using a pulsed ultrasound field, the two-dimensional velocity vector can be determined with the invention. The method uses a transversally modulated ultrasound field for probing the moving medium under investigation. A modified autocorrelation approach is used in the velocity estimation. The new...

  9. Retrotransposon vectors for gene delivery in plants

    Directory of Open Access Journals (Sweden)

    Hou Yi

    2010-08-01

    Full Text Available Abstract Background Retrotransposons are abundant components of plant genomes, and although some plant retrotransposons have been used as insertional mutagens, these mobile genetic elements have not been widely exploited for plant genome manipulation. In vertebrates and yeast, retrotransposons and retroviruses are routinely altered to carry additional genes that are copied into complementary (cDNA through reverse transcription. Integration of cDNA results in gene delivery; recombination of cDNA with homologous chromosomal sequences can create targeted gene modifications. Plant retrotransposon-based vectors, therefore, may provide new opportunities for plant genome engineering. Results A retrotransposon vector system was developed for gene delivery in plants based on the Tnt1 element from Nicotiana tabacum. Mini-Tnt1 transfer vectors were constructed that lack coding sequences yet retain the 5' and 3' long terminal repeats (LTRs and adjacent cis sequences required for reverse transcription. The internal coding region of Tnt1 was replaced with a neomycin phosphotransferase gene to monitor replication by reverse transcription. Two different mini-Tnt1 s were developed: one with the native 5' LTR and the other with a chimeric 5' LTR that had the first 233 bp replaced by the CaMV 35 S promoter. After transfer into tobacco protoplasts, both vectors undergo retrotransposition using GAG and POL proteins provided in trans by endogenous Tnt1 elements. The transposition frequencies of mini-Tnt1 vectors are comparable with native Tnt1 elements, and like the native elements, insertion sites are within or near coding sequences. In this paper, we provide evidence that template switching occurs during mini-Tnt1 reverse transcription, indicating that multiple copies of Tnt1 mRNA are packaged into virus-like particles. Conclusions Our data demonstrate that mini-Tnt1 vectors can replicate efficiently in tobacco cells using GAG and POL proteins provided in trans by

  10. VECTOR BUNDLE, KILLING VECTOR FIELD AND PONTRYAGIN NUMBERS

    Institute of Scientific and Technical Information of China (English)

    周建伟

    1991-01-01

    Let E be a vector bundle over a compact Riemannian manifold M. We construct a natural metric on the bundle space E and discuss the relationship between the killing vector fields of E and M. Then we give a proof of the Bott-Baum-Cheeger Theorem for vector bundle E.

  11. Construction of pSiRNA-Shh recombinant retroviral vector and its application in malignant glioma cells in vitro%pSiRNA-Shh逆转录病毒载体的构建及对恶性脑胶质瘤细胞作用的离体实验研究

    Institute of Scientific and Technical Information of China (English)

    尹昌林; 吕胜青; 黄轶; 李光辉; 唐莉; 杨辉

    2007-01-01

    目的 建立逆转录病毒介导的人Shh基因RNA干扰体外表达体系并观察对恶性脑胶质瘤细胞的作用.方法 将人Shh基因RNA干扰双链转录DNA片段重组到逆转录病毒质粒Psilencer 5.1-H1 Retro中,构建成携带人Shh基因RNA干扰逆转录病毒载体pSiRNA-Shh,经PT67细胞包装后,产生的重组逆转录病毒感染恶性脑胶质瘤细胞株U251和CHG-5细胞,用WST-8、RT-PCR和Western Blotting分别检测对转染细胞活性、人Shh mRNA和蛋白表达的影响.结果 重组pSiRNA-Shh质粒经测序鉴定正确.重组逆转录病毒滴度可达210×104 CFU/ml,感染U251和CHG-5恶性脑胶质瘤细胞株后3 d能明显抑制细胞生长,RT-PCR和Western Blotting检测人Shh mRNA和蛋白表达水平明显低于阴性对照组和未干扰组.结论 携带人Shh基因RNA干扰双链转录DNA片段的逆转录病毒体现出明显的抑制恶性脑胶质瘤细胞生长作用,为下一步开展基因治疗恶性脑胶质瘤奠定了基础.

  12. Flavivirus RNAi suppression: decoding non-coding RNA

    NARCIS (Netherlands)

    Pijlman, G.P.

    2014-01-01

    Flaviviruses are important human pathogens that are transmitted by invertebrate vectors, mostly mosquitoes and ticks. During replication in their vector, flaviviruses are subject to a potent innate immune response known as antiviral RNA interference (RNAi). This defense mechanism is associated with

  13. Flavivirus RNAi suppression: decoding non-coding RNA

    NARCIS (Netherlands)

    Pijlman, G.P.

    2014-01-01

    Flaviviruses are important human pathogens that are transmitted by invertebrate vectors, mostly mosquitoes and ticks. During replication in their vector, flaviviruses are subject to a potent innate immune response known as antiviral RNA interference (RNAi). This defense mechanism is associated with

  14. On Generalized Vector Equilibrium Problems

    Institute of Scientific and Technical Information of China (English)

    An-hua Wan; Jun-yi Fu; Wei-hua Mao

    2006-01-01

    A new generalized vector equilibrium problem involving set-valued mappings and the proper quasi-concavity of set-valued mappings in topological vector spaces are introduced; its existence theorems and the convexity of the solution sets are established.

  15. Vector grammars and PN machines

    Institute of Scientific and Technical Information of China (English)

    蒋昌俊

    1996-01-01

    The concept of vector grammars under the string semantic is introduced.The dass of vector grammars is given,which is similar to the dass of Chomsky grammars.The regular vector grammar is divided further.The strong and weak relation between the vector grammar and scalar grammar is discussed,so the spectrum system graph of scalar and vector grammars is made.The equivalent relation between the regular vector grammar and Petri nets (also called PN machine) is pointed.The hybrid PN machine is introduced,and its language is proved equivalent to the language of the context-free vector grammar.So the perfect relation structure between vector grammars and PN machines is formed.

  16. Vector mesons in matter

    Indian Academy of Sciences (India)

    Gy Wolf

    2006-04-01

    One consequence of the chiral restoration is the mixing of parity partners. We look for a possible signature of the mixing of vector and axial vector mesons in heavy-ion collisions. We suggest an experimental method for its observation. The dynamical evolution of the heavy-ion collision is described by a transport equation of QMD-type evolving nucleons, * and resonances, ’s and $\\sum$ baryons, and furthermore, ’s, ’s ’s ’s ’s and kaons with their isospin degrees of freedom. The input cross-sections and resonance parameters of the model are fitted to the available nucleon–nucleon and pion–nucleon cross-sections.

  17. Vector fields in cosmology

    CERN Document Server

    Davydov, Evgeny

    2011-01-01

    Vector fields can arise in the cosmological context in different ways, and we discuss both abelian and nonabelian sector. In the abelian sector vector fields of the geometrical origin (from dimensional reduction and Einstein-Eddington modification of gravity) can provide a very non-trivial dynamics, which can be expressed in terms of the effective dilaton-scalar gravity with the specific potential. In the non-abelian sector we investigate the Yang-Mills SU(2) theory which admits isotropic and homogeneous configuration. Provided the non-linear dependence of the lagrangian on the invariant F*F(dual), one can obtain the inflationary regime with the exponential growth of the scale factor. The effective amplitudes of the 'electric' and 'magnetic' components behave like slowly varying scalars at this regime, what allows the consideration of some realistic models with non-linear terms in the Yang-Mills lagrangian.

  18. Helices and vector bundles

    CERN Document Server

    Rudakov, A N

    1990-01-01

    This volume is devoted to the use of helices as a method for studying exceptional vector bundles, an important and natural concept in algebraic geometry. The work arises out of a series of seminars organised in Moscow by A. N. Rudakov. The first article sets up the general machinery, and later ones explore its use in various contexts. As to be expected, the approach is concrete; the theory is considered for quadrics, ruled surfaces, K3 surfaces and P3(C).

  19. Decay Constants of Vector Mesons

    Institute of Scientific and Technical Information of China (English)

    LI Heng-Mei; WAN Shao-Long

    2008-01-01

    @@ The light vector mesons are studied within the framework of the Bethe-Salpeter equation with the vector-vectortype flat-bottom potential The Bethe-Salpeter wavefunctions and the decay constants of the vector mesons are obtained. All the obtained results, fρ, fφ, and fΚ* , are in agreement with the experimental values, respectively.

  20. Student Preconceptions about Vector Kinematics.

    Science.gov (United States)

    Aguirre, Jose M.

    1988-01-01

    Examines preconceptions regarding several implicit vector characteristics that 15- to 17-year-old students possess just before taking their first physics course. Shows seven vector characteristics and three tasks for interviewing students. Presents the most common student preconceptions regarding each of the implicit vector characteristics. (YP)

  1. Interpolation of Vector Measures

    Institute of Scientific and Technical Information of China (English)

    Ricardo del CAMPO; Antonio FERN(A)NDEZ; Fernando MAYORAL; Francisco NARANJO; Enrique A. S(A)NCHEZ-P(E)REZ

    2011-01-01

    Let (Ω, ∑) be a measurable space and m0: ∑→ X0 and m1: ∑ -→ X1 be positive vector measures with values in the Banach K(o)the function spaces X0 and X1. If 0 < α < 1, we define a X10-αXα1 and we analyze the space of integrable functions with respect to measure [m0, m1]α in order to prove suitable extensions of the classical Stein-Weiss formulas that hold for the complex interpolation of Lp-spaces.Since each p-convex order continuous K(o)the function space with weak order unit can be represented as a space of p-integrable functions with respect to a vector measure, we provide in this way a technique to obtain representations of the corresponding complex interpolation spaces. As applications, we provide a Riesz-Thorin theorem for spaces of p-integrable functions with respect to vector measures and a formula for representing the interpolation of the injective tensor product of such spaces.

  2. Retrovirus-delivered siRNA

    Directory of Open Access Journals (Sweden)

    Devroe Eric

    2002-08-01

    Full Text Available Abstract Background The ability of transfected synthetic small interfering (si RNAs to suppress the expression of specific transcripts has proved a useful technique to probe gene function in mammalian cells. However, high production costs limit this technology's utility for many laboratories and experimental situations. Recently, several DNA-based plasmid vectors have been developed that direct transcription of small hairpin RNAs, which are processed into functional siRNAs by cellular enzymes. Although these vectors provide certain advantages over chemically synthesized siRNAs, numerous disadvantages remain including merely transient siRNA expression and low and variable transfection efficiency. Results To overcome several limitations of plasmid-based siRNA, a retroviral siRNA delivery system was developed based on commerically available vectors. As a pilot study, a vector was designed to target the human Nuclear Dbf2-Related (NDR kinase. Cells infected with the anti-NDR siRNA virus dramatically downregulate NDR expression, whereas control viruses have no effect on total NDR levels. To confirm and extend these findings, an additional virus was constructed to target a second gene, transcriptional coactivator p75. Conclusion The experiments presented here demonstrate that retroviruses are efficient vectors for delivery of siRNA into mammalian cells. Retrovirus-delivered siRNA provides significant advancement over previously available methods by providing efficient, uniform delivery and immediate selection of stable "knock-down" cells. This development should provide a method to rapidly assess gene function in established cell lines, primary cells, or animals.

  3. Non-viral vectors for gene-based therapy.

    Science.gov (United States)

    Yin, Hao; Kanasty, Rosemary L; Eltoukhy, Ahmed A; Vegas, Arturo J; Dorkin, J Robert; Anderson, Daniel G

    2014-08-01

    Gene-based therapy is the intentional modulation of gene expression in specific cells to treat pathological conditions. This modulation is accomplished by introducing exogenous nucleic acids such as DNA, mRNA, small interfering RNA (siRNA), microRNA (miRNA) or antisense oligonucleotides. Given the large size and the negative charge of these macromolecules, their delivery is typically mediated by carriers or vectors. In this Review, we introduce the biological barriers to gene delivery in vivo and discuss recent advances in material sciences, nanotechnology and nucleic acid chemistry that have yielded promising non-viral delivery systems, some of which are currently undergoing testing in clinical trials. The diversity of these systems highlights the recent progress of gene-based therapy using non-viral approaches.

  4. siRNA-mediated inhibition of HBV replication and expression

    Institute of Scientific and Technical Information of China (English)

    Xiao-Nan Zhang; Wei Xiong; Jia-Dong Wang; Yun-Wen Hu; Li Xiang; Zheng-Hong Yuan

    2004-01-01

    AIM: RNA interference (RNAi) is a newly discovered phenomenon provoked by dsRNA. The dsRNA is initially cleaved by Dicer into 21-23 nt small interfering RNA (siRNA)and can then specifically target homologous mRNA for degradation by cellular ribonucleases. RNAi has been successfully utilized to down-regulate the endogenous gene expression or suppress the replication of various pathogens in mammalian cells. In this study, we investigated whether vector-based siRNA promoted by U6 (pSilencer1.0-U6)could efficiently inhibit HBV replication in cell culture.METHODS: pSilencer vectors with inserts targeting on different regions of HBV genome were constructed. These plasmids were co-transfected with pHBV3.8 into Huh-7 cells via lipofection and viral antigens were measured by ELISA.Viral RNA was analyzed by Northern blot. The mRNA of MxA and 2′-5′OAS was reverse transcribed and quantified by real-time PCR.RESULTS: Vector-based siRNA could potently reduce hepatitis B virus antigen expression in transient replicative cell culture. Furthermore, Northern blot analysis showed that viral RNA was effectively degraded, thus eliminating the messengers for protein expression as well as template for reverse transcription. Real-time PCR analysis of cellular MxA and 2′-5′OAS gene expression revealed that vectorbased siRNA did not provoke the interferon pathway which reassured the specificity of the vector-based RNA interference technique.CONCLUSION: Our results indicate that RNA interference may be a potential tool to control HBV infection.

  5. Live bacterial vaccine vectors: An overview

    Directory of Open Access Journals (Sweden)

    Adilson José da Silva

    2014-12-01

    Full Text Available Genetically attenuated microorganisms, pathogens, and some commensal bacteria can be engineered to deliver recombinant heterologous antigens to stimulate the host immune system, while still offering good levels of safety. A key feature of these live vectors is their capacity to stimulate mucosal as well as humoral and/or cellular systemic immunity. This enables the use of different forms of vaccination to prevent pathogen colonization of mucosal tissues, the front door for many infectious agents. Furthermore, delivery of DNA vaccines and immune system stimulatory molecules, such as cytokines, can be achieved using these special carriers, whose adjuvant properties and, sometimes, invasive capacities enhance the immune response. More recently, the unique features and versatility of these vectors have also been exploited to develop anti-cancer vaccines, where tumor-associated antigens, cytokines, and DNA or RNA molecules are delivered. Different strategies and genetic tools are constantly being developed, increasing the antigenic potential of agents delivered by these systems, opening fresh perspectives for the deployment of vehicles for new purposes. Here we summarize the main characteristics of the different types of live bacterial vectors and discuss new applications of these delivery systems in the field of vaccinology.

  6. Construction of Cannabinoid Receptor 1 Gene(CNR1)siRNA Expression Vector and Screening of CNR1-interference Positive L6 Cell Clones%大麻素Ⅰ型受体基因(CNR1)特异性siRNA表达载体的构建及稳定干扰阳性L6细胞克隆的筛选

    Institute of Scientific and Technical Information of China (English)

    徐娥; 任阳; 朱琳娜; 伍婷; 袁章琴; 黄艳娜; 汪以真

    2012-01-01

    The cannabinoid receptor type 1 (CNR1) is a key component of the endocannabinoid system, which has been reported to play a pivotal role in modulating feeding behavior and energy balance. In order to further study on gene function of CNR1, this study was conducted to construct and identify CNR1 gene small interfering (siRNA) expression vectors and screened the stable CNR1- interference positive L6 cell clones. Three pairs of CNR 1-specific double-strand siRNAs were designed and inserted into the pYr-1.1 vector. The CNR1 gene siRNA expression vectors were identified by restriction enzyme digestion and sequencing. After that siRNAs were transfected with L6 cells by LipofectamineTM(Lip)2000. Then, the transfection efficiency was detected by EGFP and FCM. CNR1 gene expression was determined by Real-time PCR and the stable transgenic L6 cell clones were screened by G418. The results revealed that the CNR1 gene siRNA expression vectors have been constructed successfully. The transient transfection efficiencies of L6 cells were 10.45% (P<0.01), 8.57%(P<0.01)and 8.71% (P<0.01) respectively, and the silencing efficacies of the transient transfected L6 cells were 39%(P<0.05), 64%(P<0.01) and 68%(P<0.01), respectively. The optimal selection concentration of G418 for stable transfected L6 cell clones was 800 μg/mL. The silencing efficacies of CNR-1-positive transgenic cell clones were 43%(P<0.05), 18%(P<0.01) and 91%(P<0.01), respectively. The results showed that CNR1-3 expression vector was optimal silencing vector and CNR1-3 stable transgenic cell clones were best silencing cell line. This study successfully provides CNR1 gene silencing method by siRNA and the screening of CNR1-interference positive L6 cell clones renders basic tools for further studying the functions of CNR1 gene.%大麻素Ⅰ型受体(CNR1)是介导内源性大麻素发挥作用的关键分子,在食欲和能量代谢调控中发挥着重要作用.为了更深入研究CNR1的基因功能,本实验旨在

  7. Shortcomings of short hairpin RNA-based transgenic RNA interference in mouse oocytes

    Directory of Open Access Journals (Sweden)

    Sedlacek Radislav

    2010-10-01

    Full Text Available Abstract Background RNA interference (RNAi is a powerful approach to study a gene function. Transgenic RNAi is an adaptation of this approach where suppression of a specific gene is achieved by expression of an RNA hairpin from a transgene. In somatic cells, where a long double-stranded RNA (dsRNA longer than 30 base-pairs can induce a sequence-independent interferon response, short hairpin RNA (shRNA expression is used to induce RNAi. In contrast, transgenic RNAi in the oocyte routinely employs a long RNA hairpin. Transgenic RNAi based on long hairpin RNA, although robust and successful, is restricted to a few cell types, where long double-stranded RNA does not induce sequence-independent responses. Transgenic RNAi in mouse oocytes based on a shRNA offers several potential advantages, including simple cloning of the transgenic vector and an ability to use the same targeting construct in any cell type. Results Here we report our experience with shRNA-based transgenic RNAi in mouse oocytes. Despite optimal starting conditions for this experiment, we experienced several setbacks, which outweigh potential benefits of the shRNA system. First, obtaining an efficient shRNA is potentially a time-consuming and expensive task. Second, we observed that our transgene, which was based on a common commercial vector, was readily silenced in transgenic animals. Conclusions We conclude that, the long RNA hairpin-based RNAi is more reliable and cost-effective and we recommend it as a method-of-choice when a gene is studied selectively in the oocyte.

  8. Números, vectores y funciones

    OpenAIRE

    1992-01-01

    El texto Números, Vectores y Funciones que han elaborado los profesores Asociados Omar Evelio Ospina y Bernardo Acevedo, responden a esta necesidad con sobresalientes cualidades pedagógicas, entre las cuales se destacan el desarrollo detallado de los temas y la proliferación de ejercicios resueltos, lo cual genera un diálogo directo con el lector que puede así aprovechar totalmente su lectura. El material presentado es el fruto de un cuidadoso análisis de los autores, sobre las experiencias d...

  9. Vector polarimetry at MAMI

    Energy Technology Data Exchange (ETDEWEB)

    Nillius, Fabian; Aulenbacher, Kurt [Institut fuer Kernphysik, Johannes Gutenberg-Universitaet Mainz (Germany)

    2013-07-01

    Electron/photon tensor-correlation coefficients may allow to design a polarimeter that can measure all components of beam polarisation simultaneously (''vector polarimeter''). Besides its purpose as a beam diagnostic device this would also allow to test theoretical predictions for the correlation coefficients at energies between 1 and 3.5 MeV. As a first step we have set up a measurement of the helicity transfer to the photon as a function of energy which is based on the Compton absorption method. Apparative developments in order to measure photon emission asymmetries caused by transverse and longitudinal electron polarisation are presented.

  10. Vector-borne diseases

    DEFF Research Database (Denmark)

    More, Simon J.; Bicout, Dominique; Bøtner, Anette

    2017-01-01

    After a request from the Europea n Commission, EFSA’s Panel on Animal Health and Welfaresummarised the main characteristics of 36 vector-borne disease s (VBDs) in 36 web-based storymaps.The risk of introduction in the EU through movement of livestock or pets was assessed for eac h of the36 VBDs...... new information becomesavailable. Since this risk assessment was carried out for large regions in the EU for many VBD-agents,it should be considered as a first screening. If a more detailed risk assessment for a specificVBDiswished for on a national or subnational level, the EFSA...

  11. Relativistic Rotating Vector Model

    CERN Document Server

    Lyutikov, Maxim

    2016-01-01

    The direction of polarization produced by a moving source rotates with the respect to the rest frame. We show that this effect, induced by pulsar rotation, leads to an important correction to polarization swings within the framework of rotating vector model (RVM); this effect has been missed by previous works. We construct relativistic RVM taking into account finite heights of the emission region that lead to aberration, time-of-travel effects and relativistic rotation of polarization. Polarizations swings at different frequencies can be used, within the assumption of the radius-to-frequency mapping, to infer emission radii and geometry of pulsars.

  12. Vector potential photoelectron microscopy.

    Science.gov (United States)

    Browning, R

    2011-10-01

    A new class of electron microscope has been developed for the chemical microanalysis of a wide range of real world samples using photoelectron spectroscopy. Highly structured, three-dimensional samples, such as fiber mats and fracture surfaces can be imaged, as well as insulators and magnetic materials. The new microscope uses the vector potential field from a solenoid magnet as a spatial reference for imaging. A prototype instrument has demonstrated imaging of uncoated silk, magnetic steel wool, and micron-sized single strand tungsten wires.

  13. Transfer and Expression of Small Interfering RNAs in Mammalian Cells Using Lentiviral Vectors.

    Science.gov (United States)

    Lebedev, T D; Spirin, P V; Prassolov, V S

    2013-04-01

    RNA interference is a convenient tool for modulating gene expression. The widespread application of RNA interference is made difficult because of the imperfections of the methods used for efficient target cell delivery of whatever genes are under study. One of the most convenient and efficient gene transfer and expression systems is based on the use of lentiviral vectors, which direct the synthesis of small hairpin RNAs (shRNAs), the precursors of siRNAs. The application of these systems enables one to achieve sustainable and long-term shRNA expression in cells. This review considers the adaptation of the processing of artificial shRNA to the mechanisms used by cellular microRNAs and simultaneous expression of several shRNAs as potential approaches for producing lentiviral vectors that direct shRNA synthesis. Approaches to using RNA interference for the treatment of cancer, as well as hereditary and viral diseases, are under active development today. The improvement made to the methods for constructing lentiviral vectors and the investigation into the mechanisms of processing of small interfering RNA allow one to now consider lentiviral vectors that direct shRNA synthesis as one of the most promising tools for delivering small interfering RNAs.

  14. Lentiviral vectors in neurodegenrative disorders - Aspects in gene therapy and disease models

    DEFF Research Database (Denmark)

    Nielsen, Troels Tolstrup

    2009-01-01

    , which is most often only satisfactory in the initial phase of the disease. Gene therapy is a novel treatment strategy intended to treat or alleviate disease by genetically modifying cells by introducing nucleic acids into the cells. Lentiviral vectors hold great promise as gene transfer vectors...... and are able to transduce post-mitotic cells e.g. terminally differentiated neurons, making them ideal candidates for gene transfer to the brain and as experimental tools. In this study vectors expressing miRNA embedded shRNA from pol II-promoters were constructed for RNA interference (RNAi) in vitro...... and in vivo. Robust gene knock-down was shown using a ubiquitous promoter (CMV) and for the first time neuron specific RNAi was obtained using a neuron specific promoter (NSE). Furthermore, optimization of lentiviral vectors was conducted using an insulator element (cHS4) in order to enhance transgene...

  15. Retroviral vector production under serum deprivation: The role of lipids.

    Science.gov (United States)

    Rodrigues, A F; Carmo, M; Alves, P M; Coroadinha, A S

    2009-12-15

    The use of retroviral vectors for gene therapy applications demands high titer preparations and stringent quality standards. However, the manufacturing of these vectors still represents a highly challenging task due to the low productivity of the cell lines and reduced stability of the vector infectivity, particularly under serum-free conditions. With the objective of understanding the major limitations of retroviral vector production under serum deprivation, a thorough study of viral production kinetics, vector characterization and cell growth and metabolic behavior was conducted, for 293 FLEX 18 and Te Fly Ga 18 producer cell lines using different serum concentrations. The reduction of serum supplementation in the culture medium resulted in pronounced decreases in cell productivity of infectious vector, up to ninefold in 293 FLEX 18 cells and sevenfold in Te Fly Ga 18 cells. Total particles productivity was maintained, as assessed by measuring viral RNA; therefore, the decrease in infectious vector production could be attributed to higher defective particles output. The absence of the serum lipid fraction was found to be the major cause for this decrease in cell viral productivity. The use of delipidated serum confirmed the requirement of serum lipids, particularly cholesterol, as its supplementation not only allowed the total recovery of viral titers as well as additional production increments in both cell lines when comparing with the standard 10% (v/v) FBS supplementation. This work identified lower production ratios of infectious particles/total particles as the main restraint of retroviral vector production under serum deprivation; this is of the utmost importance concerning the clinical efficacy of the viral preparations. Lipids were confirmed as the key serum component correlated with the production of infective retroviral vectors and this knowledge can be used to efficiently design medium supplementation strategies for serum-free production. Biotechnol

  16. Stabilization of Clostridium perfringens collagenase mRNA by VR-RNA-dependent cleavage in 5' leader sequence.

    Science.gov (United States)

    Obana, Nozomu; Shirahama, Yu; Abe, Kimihiro; Nakamura, Kouji

    2010-09-01

    The small RNA (sRNA), VR-RNA that is directly regulated by the VirR/VirS two-component system, regulates many genes including toxin genes such as collagenase (colA) and phospholipase C (plc) in Clostridium perfringens. Although the VR-RNA 3' region is sufficient to regulate the colA and plc genes, the molecular mechanism of toxin gene regulation by VR-RNA remains unclear. Here, we found that colA mRNA is cleaved at position -79 and -78 from the A of the first codon (ATG) in the presence of VR-RNA. The processed transcripts were stable compared with longer intact transcripts. On the other hand, colA mRNA was labile in a VR-RNA-deficient strain, and processed transcripts were undetectable. The stability and processing of colA mRNA were restored by transformation of the 3' region of VR-RNA-expression vector. The 3' region of VR-RNA and colA mRNA had significant complementation and interacted in vitro. These results show that VR-RNA base pairs with colA mRNA and induces cleavage in the 5' untranslated region (UTR) of colA mRNA, which leads to the stabilization of colA mRNA and the activation of colA expression. © 2010 Blackwell Publishing Ltd.

  17. Alphavirus transducing system: tools for visualizing infection in mosquito vectors.

    Science.gov (United States)

    Phillips, Aaron; Mossel, Eric; Sanchez-Vargas, Irma; Foy, Brian; Olson, Ken

    2010-11-24

    Alphavirus transducing systems (ATSs) are important tools for expressing genes of interest (GOI) during infection. ATSs are derived from cDNA clones of mosquito-borne RNA viruses (genus Alphavirus; family Togaviridae). The Alphavirus genus contains about 30 different mosquito-borne virus species. Alphaviruses are enveloped viruses and contain single-stranded RNA genomes (~11.7 Kb). Alphaviruses transcribe a subgenomic mRNA that encodes the structural proteins of the virus required for encapsidation of the genome and maturation of the virus. Alphaviruses are usually highly lytic in vertebrate cells, but persistently infect susceptible mosquito cells with minimal cytopathology. These attributes make them excellent tools for gene expression in mosquito vectors. The most common ATSs in use are derived from Sindbis virus (SINV). The broad species tropism of SINV allows for infection of insect, avian, and mammalian cells8. However, ATSs have been derived from other alphaviruses as well. Foreign gene expression is made possible by the insertion of an additional viral subgenomic RNA initiation site or promoter. ATSs in which an exogenous gene sequence is positioned 5' to the viral structural genes is used for stable protein expression in insects. ATSs, in which a gene sequence is positioned 3' to the structural genes, is used to trigger RNAi and silence expression of that gene in the insect. ATSs have proven to be valuable tools for understanding vector-pathogen interactions, molecular details of viral replication and maintenance infectious cycles. In particular, the expression of fluorescent and bioluminescent reporters has been instrumental tracking the viral infection in the vector and virus transmission. Additionally, the vector immune response has been described using two strains of SINV engineered to express GFP(2,9). Here, we present a method for the production of SINV containing a fluorescent reporter (GFP) from the cDNA infectious clone. Infectious, full

  18. Extended vector-tensor theories

    Science.gov (United States)

    Kimura, Rampei; Naruko, Atsushi; Yoshida, Daisuke

    2017-01-01

    Recently, several extensions of massive vector theory in curved space-time have been proposed in many literatures. In this paper, we consider the most general vector-tensor theories that contain up to two derivatives with respect to metric and vector field. By imposing a degeneracy condition of the Lagrangian in the context of ADM decomposition of space-time to eliminate an unwanted mode, we construct a new class of massive vector theories where five degrees of freedom can propagate, corresponding to three for massive vector modes and two for massless tensor modes. We find that the generalized Proca and the beyond generalized Proca theories up to the quartic Lagrangian, which should be included in this formulation, are degenerate theories even in curved space-time. Finally, introducing new metric and vector field transformations, we investigate the properties of thus obtained theories under such transformations.

  19. Semitopological Vector Spaces and Hyperseminorms

    Directory of Open Access Journals (Sweden)

    Mark Burgin

    2013-11-01

    Full Text Available In this paper, we introduce and study semitopological vector spaces. The goal is to provide an efficient base for developing the theory of extrafunction spaces in an abstract setting of algebraic systems and topological spaces. Semitopological vector spaces are more general than conventional topological vector spaces, which proved to be very useful for solving many problems in functional analysis. To study semitopological vector spaces, hypermetrics and hyperpseudometrics are introduced and it is demonstrated that hyperseminorms, studied in previous works of the author, induce hyperpseudometrics, while hypernorms induce hypermetrics. Sufficient and necessary conditions for a hyperpseudometric (hypermetric to be induced by a hyperseminorm (hypernorm are found. We also show that semitopological vector spaces are closely related to systems of hyperseminorms. Then defining boundedness and continuity relative to associated systems of hyperseminorms, we study relations between relative boundedness and relative continuity for mappings of vector spaces with systems of hyperseminorms and systems of hypernorms.

  20. Engineering Structurally Interacting RNA (sxRNA)

    Science.gov (United States)

    Doyle, Francis; Lapsia, Sameer; Spadaro, Salvatore; Wurz, Zachary E.; Bhaduri-McIntosh, Sumita; Tenenbaum, Scott A.

    2017-01-01

    RNA-based three-way junctions (3WJs) are naturally occurring structures found in many functional RNA molecules including rRNA, tRNA, snRNA and ribozymes. 3WJs are typically characterized as resulting from an RNA molecule folding back on itself in cis but could also form in trans when one RNA, for instance a microRNA binds to a second structured RNA, such as a mRNA. Trans-3WJs can influence the final shape of one or both of the RNA molecules and can thus provide a means for modulating the availability of regulatory motifs including potential protein or microRNA binding sites. Regulatory 3WJs generated in trans represent a newly identified regulatory category that we call structurally interacting RNA or sxRNA for convenience. Here we show that they can be rationally designed using familiar cis-3WJ examples as a guide. We demonstrate that an sxRNA “bait” sequence can be designed to interact with a specific microRNA “trigger” sequence, creating a regulatable RNA-binding protein motif that retains its functional activity. Further, we show that when placed downstream of a coding sequence, sxRNA can be used to switch “ON” translation of that sequence in the presence of the trigger microRNA and the amount of translation corresponded with the amount of microRNA present. PMID:28350000

  1. RNA Replicons - A New Approach for Influenza Virus Immunoprophylaxis

    Directory of Open Access Journals (Sweden)

    Gert Zimmer

    2010-01-01

    Full Text Available RNA replicons are derived from either positive- or negative-strand RNA viruses. They represent disabled virus vectors that are not only avirulent, but also unable to revert to virulence. Due to autonomous RNA replication, RNA replicons are able to drive high level, cytosolic expression of recombinant antigens stimulating both the humoral and the cellular branch of the immune system. This review provides an update on the available literature covering influenza virus vaccines based on RNA replicons. The pros and cons of these vaccine strategies will be discussed and future perspectives disclosed.

  2. VLSI Processor For Vector Quantization

    Science.gov (United States)

    Tawel, Raoul

    1995-01-01

    Pixel intensities in each kernel compared simultaneously with all code vectors. Prototype high-performance, low-power, very-large-scale integrated (VLSI) circuit designed to perform compression of image data by vector-quantization method. Contains relatively simple analog computational cells operating on direct or buffered outputs of photodetectors grouped into blocks in imaging array, yielding vector-quantization code word for each such block in sequence. Scheme exploits parallel-processing nature of vector-quantization architecture, with consequent increase in speed.

  3. Vectors in a Box

    CERN Document Server

    Buchin, Kevin; Moser, Robin A; Pálvölgyi, Dömötör

    2009-01-01

    For an integer d>=1, let tau(d) be the smallest integer with the following property: If v1,v2,...,vt is a sequence of t>=2 vectors in [-1,1]^d with v1+v2+...+vt in [-1,1]^d, then there is a subset S of {1,2,...,t} of indices, 2= d^{d/2-o(d)}. These results contribute to understanding the master equality polyhedron with multiple rows defined by Dash et al., which is a "universal" polyhedron encoding valid cutting planes for integer programs (this line of research was started by Gomory in the late 1960s). In particular, the upper bound on tau(d) implies a pseudo-polynomial running time for an algorithm of Dash et al. for integer programming with a fixed number of constraints. The algorithm consists in solving a linear program, and it provides an alternative to a 1981 dynamic programming algorithm of Papadimitriou.

  4. Entangled vector vortex beams

    Science.gov (United States)

    D'Ambrosio, Vincenzo; Carvacho, Gonzalo; Graffitti, Francesco; Vitelli, Chiara; Piccirillo, Bruno; Marrucci, Lorenzo; Sciarrino, Fabio

    2016-09-01

    Light beams having a vectorial field structure, or polarization, that varies over the transverse profile and a central optical singularity are called vector vortex (VV) beams and may exhibit specific properties such as focusing into "light needles" or rotation invariance. VV beams have already found applications in areas ranging from microscopy to metrology, optical trapping, nano-optics, and quantum communication. Individual photons in such beams exhibit a form of single-particle quantum entanglement between different degrees of freedom. On the other hand, the quantum states of two photons can be also entangled with each other. Here, we combine these two concepts and demonstrate the generation of quantum entanglement between two photons that are both in VV states: a form of entanglement between two complex vectorial fields. This result may lead to quantum-enhanced applications of VV beams as well as to quantum information protocols fully exploiting the vectorial features of light.

  5. Solar imaging vector magnetograph

    Science.gov (United States)

    Canfield, Richard C.

    1993-01-01

    This report describes an instrument which has been constructed at the University of Hawaii to make observations of the magnetic field in solar active regions. Detailed knowledge of active region magnetic structures is crucial to understanding many solar phenomena, because the magnetic field both defines the morphology of structures seen in the solar atmosphere and is the apparent energy source for solar flares. The new vector magnetograph was conceived in response to a perceived discrepancy between the capabilities of X ray imaging telescopes to be operating during the current solar maximum and those of existing magnetographs. There were no space-based magnetographs planned for this period; the existing ground-based instruments variously suffered from lack of sensitivity, poor time resolution, inadequate spatial resolution or unreliable sites. Yet the studies of flares and their relationship to the solar corona planned for the 1991-1994 maximum absolutely required high quality vector magnetic field measurements. By 'vector' measurements we mean that the observation attempts to deduce the complete strength and direction of the field at the measurement site, rather than just the line of sight component as obtained by a traditional longitudinal magnetograph. Knowledge of the vector field permits one to calculate photospheric electric currents, which might play a part in heating the corona, and to calculate energy stored in coronal magnetic fields as the result of such currents. Information about the strength and direction of magnetic fields in the solar atmosphere can be obtained in a number of ways, but quantitative data is best obtained by observing Zeeman-effect polarization in solar spectral lines. The technique requires measuring the complete state of polarization at one or more wavelengths within a magnetically sensitive line of the solar spectrum. This measurement must be done for each independent spatial point for which one wants magnetic field data. All the

  6. Resonance vector mode locking

    CERN Document Server

    Kolpakov, Stanislav A; Loika, Yuri; Tarasov, Nikita; Kalashnikov, Vladimir; Agrawal, Govind P

    2015-01-01

    A mode locked fibre laser as a source of ultra-stable pulse train has revolutionised a wide range of fundamental and applied research areas by offering high peak powers, high repetition rates, femtosecond range pulse widths and a narrow linewidth. However, further progress in linewidth narrowing seems to be limited by the complexity of the carrier-envelope phase control. Here for the first time we demonstrate experimentally and theoretically a new mechanism of resonance vector self-mode locking where tuning in-cavity birefringence leads to excitation of the longitudinal modes sidebands accompanied by the resonance phase locking of sidebands with the adjacent longitudinal modes. An additional resonance with acoustic phonons provides the repetition rate tunability and linewidth narrowing down to Hz range that drastically reduces the complexity of the carrier-envelope phase control and so will open the way to advance lasers in the context of applications in metrology, spectroscopy, microwave photonics, astronomy...

  7. DDX3 DEAD-box RNA helicase is required for hepatitis C virus RNA replication.

    Science.gov (United States)

    Ariumi, Yasuo; Kuroki, Misao; Abe, Ken-ichi; Dansako, Hiromichi; Ikeda, Masanori; Wakita, Takaji; Kato, Nobuyuki

    2007-12-01

    DDX3, a DEAD-box RNA helicase, binds to the hepatitis C virus (HCV) core protein. However, the role(s) of DDX3 in HCV replication is still not understood. Here we demonstrate that the accumulation of both genome-length HCV RNA (HCV-O, genotype 1b) and its replicon RNA were significantly suppressed in HuH-7-derived cells expressing short hairpin RNA targeted to DDX3 by lentivirus vector transduction. As well, RNA replication of JFH1 (genotype 2a) and release of the core into the culture supernatants were suppressed in DDX3 knockdown cells after inoculation of the cell culture-generated HCVcc. Thus, DDX3 is required for HCV RNA replication.

  8. Vector-Tensor and Vector-Vector Decay Amplitude Analysis of B0->phi K*0

    CERN Document Server

    Aubert, B; Abrams, G S; Adye, T; Ahmed, S; Alam, M S; Albert, J; Aleksan, R; Allen, M T; Allison, J; Altenburg, D D; Andreotti, M; Angelini, C; Anulli, F; Arnaud, N; Asgeirsson, D J; Aston, D; Azzolini, V; Baak, M A; Back, J J; Baldini-Ferroli, R; Band, H R; Banerjee, Sw; Bard, D J; Barlow, N R; Barlow, R J; Barrett, M; Bartoldus, R; Batignani, G; Battaglia, M; Bauer, J M; Bechtle, P; Beck, T W; Behera, P K; Bellini, F; Benayoun, M; Benelli, G; Berger, N; Bernard, D; Berryhill, J W; Best, D S; Bettarini, S; Bettoni, D; Bevan, A J; Bhimji, W; Bhuyan, B; Bianchi, F; Biasini, M; Biesiada, J; Blanc, F; Blaylock, G; Blinov, V E; Bloom, P C; Blount, N L; Bomben, M; Bondioli, M; Bonneaud, G R; Bosisio, L; Boutigny, D; Bowerman, D A; Boyd, J T; Bozzi, C; Brandenburg, G; Brandt, T; Brau, J E; Briand, H; Brown, C M; Brown, D N; Bruinsma, M; Brunet, S; Bucci, F; Buchanan, C; Bugg, W; Bukin, A D; Bula, R; Burchat, P R; Burke, J P; Button-Shafer, J; Buzzo, A; Bóna, M; Cahn, R N; Calabrese, R; Calcaterra, A; Calderini, G; Campagnari, C; Carpinelli, M; Cartaro, C; Cavallo, N; Cavoto, G; Cenci, R; Chai, X; Chaisanguanthum, K S; Chao, M; Charles, E; Charles, M J; Chauveau, J; Chavez, C A; Chen, A; Chen, C; Chen, E; Chen, J C; Chen, S; Chen, X; Chen, X R; Cheng, B; Cheng, C H; Chia, Y M; Cibinetto, G; Clark, P J; Clarke, C K; Claus, R; Cochran, J; Coleman, J P; Contri, R; Convery, M R; Corwin, L A; Cossutti, F; Cottingham, W N; Couderc, F; Covarelli, R; Cowan, G; Cowan, R; Crawley, H B; Cremaldi, L; Cunha, A; Curry, S; Côté, D; D'Orazio, A; Dahmes, B; Dallapiccola, C; Danielson, N; Dasu, S; Datta, M; Dauncey, P D; David, P; Davier, M; Davis, C L; De Nardo, Gallieno; De Sangro, R; Del Amo-Sánchez, P; Del Buono, L; Del Re, D; Della Ricca, G; Denig, A G; Di Lodovico, F; Di Marco, E; Dingfelder, J C; Dittongo, S; Dong, L; Dorfan, J; Druzhinin, V P; Dubitzky, R S; Dubois-Felsmann, G P; Dujmic, D; Dunwoodie, W M; Dvoretskii, A; Ebert, M; Eckhart, E A; Eckmann, R; Edgar, C L; Edwards, A J; Egede, U; Eigen, G; Eisner, A M; Elmer, P; Emery, S; Ernst, J A; Eschenburg, V; Eschrich, I; Eyges, V; Fabozzi, F; Faccini, R; Fang, F; Feltresi, E; Ferrarotto, F; Ferroni, F; Field, R C; Finocchiaro, G; Flacco, C J; Flack, R L; Flächer, H U; Flood, K T; Ford, K E; Ford, W T; Forster, I J; Forti, F; Fortin, D; Foulkes, S D; Franek, B; Frey, R; Fritsch, M; Fry, J R; Fulsom, B G; Gabathuler, E; Gaidot, A; Gallo, F; Gamba, D; Gamet, R; Gan, K K; Ganzhur, S F; Gao, Y; Gary, J W; Gaspero, M; Gatto, C; Gaz, A; George, K A; Gill, M S; Giorgi, M A; Gladney, L; Glanzman, T; Godang, R; Golubev, V B; Gowdy, S J; Gradl, W; Graham, M T; Graugès-Pous, E; Grenier, P; Gritsan, A V; Grosdidier, G; Groysman, Y; Guo, Z J; Hadavand, H K; Haire, M; Halyo, V; Hamano, K; Hamel de Monchenault, G; Hamon, O; Harrison, P F; Harrison, T J; Hart, A J; Hartfiel, B L; Hast, C; Hauke, A; Hawkes, C M; Hearty, C; Held, T; Hertzbach, S S; Heusch, C A; Hill, E J; Hirschauer, J F; Hitlin, D G; Hollar, J J; Hong, T M; Honscheid, K; Hopkins, D A; Hrynóva, T; Hufnagel, D; Hulsbergen, W D; Hutchcroft, D E; Höcker, A; Igonkina, O; Innes, W R; Izen, J M; Jackson, P D; Jackson, P S; Jacobsen, R G; Jain, V; Jasper, H; Jawahery, A; Jessop, C P; Judd, D; Kadyk, J A; Kagan, H; Karyotakis, Yu; Kass, R; Kelsey, M H; Kerth, L T; Khan, A; Kim, H; Kim, P; Kirkby, D; Klose, V; Knecht, N S; Koch, H; Kolb, J A; Kolomensky, Yu G; Kovalskyi, D; Kowalewski, R V; Kozanecki, Witold; Kreisel, A; Krishnamurthy, M; Kroeger, R; Kroseberg, J; Kukartsev, G; Kutter, P E; Kyberd, P; La Vaissière, C de; Lacker, H M; Lae, C K; Lafferty, G D; Lanceri, L; Lange, D J; Lankford, A J; Latham, T E; Latour, E; Lau, Y P; Lazzaro, A; Le Diberder, F R; Lee, C L; Lees, J P; Legendre, M; Leith, D W G S; Lepeltier, V; Leruste, P; Lewandowski, B; Li Gioi, L; Li, S; Li, X; Lista, L; Liu, H; Lo Vetere, M; LoSecco, J M; Lockman, W S; Lombardo, V; Long, O; Lopes-Pegna, D; Lopez-March, N; Lou, X C; Lu, M; Luitz, S; Lund, P; Luppi, E; Lusiani, A; Lutz, A M; Lynch, G; Lynch, H L; Lü, C; Lüth, V; MacFarlane, D B; Macri, M M; Mader, W F; Majewski, S A; Malcles, J; Mallik, U; Mancinelli, G; Mandelkern, M A; Marchiori, G; Margoni, M; Marks, J; Marsiske, H; Martínez-Vidal, F; Mattison, T S; Mazur, M A; Mazzoni, M A; McKenna, J A; McMahon, T R; Mclachlin, S E; Meadows, B T; Mellado, B; Menges, W; Merkel, J; Messner, R; Meyer, N T; Meyer, W T; Mihályi, A; Mir, L M; Mishra, K; Mohanty, G B; Monge, M R; Monorchio, D; Moore, T B; Morandin, M; Morganti, M; Morganti, S; Morii, M; Muheim, F; Müller, D R; Nagel, M; Naisbit, M T; Narsky, I; Nash, J A; Nauenberg, U; Neal, H; Negrini, M; Neri, N; Nesom, G; Nicholson, H; Nikolich, M B; Nogowski, R; Nugent, I M; O'Grady, C P; Ocariz, J; Ofte, I; Olaiya, E O; Olivas, A; Olsen, J; Onuchin, A P; Orimoto, T J; Oyanguren, A; Ozcan, V E; Paar, H P; Pacetti, S; Palano, A; Palombo, F; Pan, B; Pan, Y; Panduro, W; Paoloni, E; Paolucci, P; Pappagallo, M; Park, W; Passaggio, S; Patel, P M; Patrignani, C; Patteri, P; Payne, D J; Pelizaeus, M; Perazzo, A; Perl, M; Peruzzi, I M; Peters, K; Petersen, B A; Petrella, A; Petzold, A; Piatenko, T; Piccolo, D; Piccolo, M; Piemontese, L; Pierini, M; Piredda, G; Playfer, S; Poireau, V; Polci, F; Pompili, A; Porter, F C; Posocco, M; Potter, C T; Prell, S; Prencipe, E; Prepost, R; Pripstein, M; Pruvot, S; Pulliam, T; Purohit, M V; Qi, N D; Rahatlou, S; Rahimi, A M; Rahmat, R; Rama, M; Ratcliff, B N; Raven, G; Regensburger, J J; Ricciardi, S; Richman, J D; Ritchie, J L; Rizzo, G; Roberts, D A; Robertson, A I; Robertson, S H; Robutti, E; Rodier, S; Roe, N A; Ronan, M T; Roney, J M; Rong, G; Roodman, A; Roos, L; Rosenberg, E I; Rotondo, M; Roudeau, P; Rubin, A E; Ruddick, W O; Röthel, W; Sacco, R; Saeed, M A; Safai-Tehrani, F; Saleem, M; Salnikov, A A; Salvatore, F; Sanders, D A; Santroni, A; Saremi, S; Satpathy, A; Schalk, T; Schenk, S; Schilling, C J; Schindler, R H; Schofield, K C; Schott, G; Schröder, T; Schröder, H; Schubert, J; Schubert, K R; Schumm, B A; Schune, M H; Schwiening, J; Schwierz, R; Schwitters, R F; Sciacca, C; Sciolla, G; Seiden, A; Sekula, S J; Serednyakov, S I; Serrano, J; Sharma, V; Shen, B C; Sherwood, D J; Simard, M; Simi, G; Simonetto, F; Sinev, N B; Skovpen, Yu I; Smith, A J S; Smith, J G; Snoek, H L; Snyder, A; Sobie, R J; Soffer, A; Sokoloff, M D; Solodov, E P; Spaan, B; Spanier, S M; Spitznagel, M; Spradlin, P; Steinke, M; Stelzer, J; Stocchi, A; Stoker, D P; Stroili, R; Strom, D; Strube, J; Stugu, B; Stängle, H; Su, D; Sullivan, M K; Summers, D J; Sundermann, J E; Suzuki, K; Swain, S K; Taras, P; Taylor, F; Telnov, A V; Teodorescu, L; Ter-Antonian, R; Therin, G; Thiebaux, C; Thompson, J M; Tisserand, V; Todyshev, Y K; Toki, W H; Torrence, E; Tosi, S; Touramanis, C; Ulmer, K A; Uwer, U; Van Bakel, N; Vasseur, G; Vavra, J; Vazquez, A; Verderi, M; Viaud, F B; Vitale, L; Voci, C; Voena, C; Volk, A; Wagner, A P; Wagner, S R; Wagoner, D E; Waldi, R; Walker, D; Walsh, J J; Wang, K; Wang, P; Wang, W F; Wappler, F R; Watson, A T; Weaver, M; Weinstein, A J R; Wenzel, W A; Wilden, L; Williams, D C; Williams, J C; Wilson, F F; Wilson, J R; Wilson, M G; Wilson, R J; Winklmeier, F; Wisniewski, W J; Wittgen, M; Wong, Q K; Wormser, G; Wren, A C; Wright, D H; Wright, D M; Wu, J; Wu, S L; Wulsin, H W; Xie, Y; Yamamoto, R K; Yarritu, A K; Ye, S; Yi, J I; Yi, K; Young, C C; Yu, Z; Yéche, C; Zain, S B; Zallo, A; Zeng, Q; Zghiche, A; Zhang, J; Zhang, L; Zhao, H W; Zhu, Y S; Ziegler, V; Zito, M; Çuhadar-Dönszelmann, T; al, et

    2007-01-01

    We perform an amplitude analysis of the decays B0->phi K^*_2(1430)0, phi K^*(892)0, and phi(K pi)^0_S-wave with a sample of about 384 million BBbar pairs recorded with the BABAR detector. The fractions of longitudinal polarization f_L of the vector-tensor and vector-vector decay modes are measured to be 0.853 +0.061-0.069 +-0.036 and 0.506 +-0.040 +-0.015, respectively. Overall, twelve parameters are measured for the vector-vector decay and seven parameters for the vector-tensor decay, including the branching fractions and parameters sensitive to CP-violation.

  9. Construction of RNAi lentiviral vector targeting mouse Islet-1 gene

    Directory of Open Access Journals (Sweden)

    Shen-shen ZHI

    2011-02-01

    Full Text Available Objective To construct and select RNAi lentiviral vectors that can silence mouse Islet-1 gene effectively.Methods Three groups of RNAi-target of mouse Islet-1 gene were designed,and corresponding shRNA oligo(sh1,sh2 and sh3 were synthesized,and then they were respectively inserted to the PLVTHM vector that had been digested by endonuclease.Agarose gel electrophoresis and sequencing were used to select and indentify the positive clones.The positive clones were extracted and then mixed with E.coli to amplify positive clones.The amplified clones were then infected into 293T along with the other 3 helper plasmids to produce lentiviral vector.After the construction of the lentiviral vector,plaque formation test was performed to determine the titer of lentiviral vector.The lentiviral vectors were then infected into C3H10T1/2 cells.The transfect efficiency of the lentiviral vectors was determined with flow cytometry with detection of green fluorescent protein(GFP.Q-PCR was employed to detect the RNAi efficiency of the lentiviral vectors.Results Agarose gel electrophoresis analysis showed that the clones with right gene at the target size were successfully established;gene sequencing showed that the right DNA fragments had been inserted;plaque formation test showed that the titer of the virus solution was 3.87×108TU/ml;the transfect efficiency of the lentiviral vector infected into C3H10T1/2 cells was 90.36%.All the 3 groups of shRNA targets(sh1,sh2 and sh3 showed an inhibitory effect on Islet-1 gene,and the sh1 showed the highest inhibitory effect(76.8%,as compared with that of normal cells(P < 0.05.Conclusion The RNAi lentiviral vector that can effectively silence the mouse Islet-1 gene has been constructed successfully,which may lay a foundation for further investigation of Islet-1 gene.

  10. siRNA release from pri-miRNA scaffolds is controlled by the sequence and structure of RNA.

    Science.gov (United States)

    Galka-Marciniak, Paulina; Olejniczak, Marta; Starega-Roslan, Julia; Szczesniak, Michal W; Makalowska, Izabela; Krzyzosiak, Wlodzimierz J

    2016-04-01

    shmiRs are pri-miRNA-based RNA interference triggers from which exogenous siRNAs are expressed in cells to silence target genes. These reagents are very promising tools in RNAi in vivo applications due to their good activity profile and lower toxicity than observed for other vector-based reagents such as shRNAs. In this study, using high-resolution northern blotting and small RNA sequencing, we investigated the precision with which RNases Drosha and Dicer process shmiRs. The fidelity of siRNA release from the commonly used pri-miRNA shuttles was found to depend on both the siRNA insert and the pri-miR scaffold. Then, we searched for specific factors that may affect the precision of siRNA release and found that both the structural features of shmiR hairpins and the nucleotide sequence at Drosha and Dicer processing sites contribute to cleavage site selection and cleavage precision. An analysis of multiple shRNA intermediates generated from several reagents revealed the complexity of shmiR processing by Drosha and demonstrated that Dicer selects substrates for further processing. Aside from providing new basic knowledge regarding the specificity of nucleases involved in miRNA biogenesis, our results facilitate the rational design of more efficient genetic reagents for RNAi technology.

  11. Execution of vector operations for Intel 860

    Energy Technology Data Exchange (ETDEWEB)

    Khaletskii, D.A.

    1995-03-01

    When designing a portable setup compiler from the C[] language, the compiler setup problem is solved for various SIMD computers. A vector and vector operations are defined in C[]. A map of vector operations is trivial for computers with vector registers. Some problems appear when mapping them to computers without vector registers. It is shown how to effectively perform vector operations for the 1860 microcomputer as an example of one without vector registers.

  12. Simian virus 40 vectors for pulmonary gene therapy

    Directory of Open Access Journals (Sweden)

    Oppenheim Ariella

    2007-10-01

    Full Text Available Abstract Background Sepsis remains the leading cause of death in critically ill patients. One of the primary organs affected by sepsis is the lung, presenting as the Acute Respiratory Distress Syndrome (ARDS. Organ damage in sepsis involves an alteration in gene expression, making gene transfer a potential therapeutic modality. This work examines the feasibility of applying simian virus 40 (SV40 vectors for pulmonary gene therapy. Methods Sepsis-induced ARDS was established by cecal ligation double puncture (2CLP. SV40 vectors carrying the luciferase reporter gene (SV/luc were administered intratracheally immediately after sepsis induction. Sham operated (SO as well as 2CLP rats given intratracheal PBS or adenovirus expressing luciferase served as controls. Luc transduction was evaluated by in vivo light detection, immunoassay and luciferase mRNA detection by RT-PCR in tissue harvested from septic rats. Vector abundance and distribution into alveolar cells was evaluated using immunostaining for the SV40 VP1 capsid protein as well as by double staining for VP1 and for the surfactant protein C (proSP-C. Immunostaining for T-lymphocytes was used to evaluate the cellular immune response induced by the vector. Results Luc expression measured by in vivo light detection correlated with immunoassay from lung tissue harvested from the same rats. Moreover, our results showed vector presence in type II alveolar cells. The vector did not induce significant cellular immune response. Conclusion In the present study we have demonstrated efficient uptake and expression of an SV40 vector in the lungs of animals with sepsis-induced ARDS. These vectors appear to be capable of in vivo transduction of alveolar type II cells and may thus become a future therapeutic tool.

  13. Genetic engineering of human embryonic stem cells with lentiviral vectors.

    Science.gov (United States)

    Xiong, Chen; Tang, Dong-Qi; Xie, Chang-Qing; Zhang, Li; Xu, Ke-Feng; Thompson, Winston E; Chou, Wayne; Gibbons, Gary H; Chang, Lung-Ji; Yang, Li-Jun; Chen, Yuqing E

    2005-08-01

    Human embryonic stem (hES) cells present a valuable source of cells with a vast therapeutic potential. However, the low efficiency of directed differentiation of hES cells remains a major obstacle in their uses for regenerative medicine. While differentiation may be controlled by the genetic manipulation, effective and efficient gene transfer into hES cells has been an elusive goal. Here, we show stable and efficient genetic manipulations of hES cells using lentiviral vectors. This method resulted in the establishment of stable gene expression without loss of pluripotency in hES cells. In addition, lentiviral vectors were effective in conveying the expression of an U6 promoter-driven small interfering RNA (siRNA), which was effective in silencing its specific target. Taken together, our results suggest that lentiviral gene delivery holds great promise for hES cell research and application.

  14. Vectors on the Basketball Court

    Science.gov (United States)

    Bergman, Daniel

    2010-01-01

    An Idea Bank published in the April/May 2009 issue of "The Science Teacher" describes an experiential physics lesson on vectors and vector addition (Brown 2009). Like its football predecessor, the basketball-based investigation presented in this Idea Bank addresses National Science Education Standards Content B, Physical Science, 9-12 (NRC 1996)…

  15. Simplified Representation of Vector Fields

    NARCIS (Netherlands)

    Telea, Alexandru; Wijk, Jarke J. van

    1999-01-01

    Vector field visualization remains a difficult task. Although many local and global visualization methods for vector fields such as flow data exist, they usually require extensive user experience on setting the visualization parameters in order to produce images communicating the desired insight. We

  16. The Neural Support Vector Machine

    NARCIS (Netherlands)

    Wiering, Marco; van der Ree, Michiel; Embrechts, Mark; Stollenga, Marijn; Meijster, Arnold; Nolte, A; Schomaker, Lambertus

    2013-01-01

    This paper describes a new machine learning algorithm for regression and dimensionality reduction tasks. The Neural Support Vector Machine (NSVM) is a hybrid learning algorithm consisting of neural networks and support vector machines (SVMs). The output of the NSVM is given by SVMs that take a

  17. Testing identifiablility of cointegrating vectors

    NARCIS (Netherlands)

    H.P. Boswijk

    1996-01-01

    This article analyzes the identification and normalization of cointegrating vectors. Normalizing a cointegrating relation with respect to one of the relevant variables is with loss of generality; and restrictions that are supposed to identify a vector may fail to do so for particular parameter value

  18. The Neural Support Vector Machine

    NARCIS (Netherlands)

    Wiering, Marco; van der Ree, Michiel; Embrechts, Mark; Stollenga, Marijn; Meijster, Arnold; Nolte, A; Schomaker, Lambertus

    2013-01-01

    This paper describes a new machine learning algorithm for regression and dimensionality reduction tasks. The Neural Support Vector Machine (NSVM) is a hybrid learning algorithm consisting of neural networks and support vector machines (SVMs). The output of the NSVM is given by SVMs that take a centr

  19. Estimation of Motion Vector Fields

    DEFF Research Database (Denmark)

    Larsen, Rasmus

    1993-01-01

    This paper presents an approach to the estimation of 2-D motion vector fields from time varying image sequences. We use a piecewise smooth model based on coupled vector/binary Markov random fields. We find the maximum a posteriori solution by simulated annealing. The algorithm generate sample...

  20. Simplified Representation of Vector Fields

    NARCIS (Netherlands)

    Telea, Alexandru; Wijk, Jarke J. van

    1999-01-01

    Vector field visualization remains a difficult task. Although many local and global visualization methods for vector fields such as flow data exist, they usually require extensive user experience on setting the visualization parameters in order to produce images communicating the desired insight. We

  1. GPU Accelerated Vector Median Filter

    Science.gov (United States)

    Aras, Rifat; Shen, Yuzhong

    2011-01-01

    Noise reduction is an important step for most image processing tasks. For three channel color images, a widely used technique is vector median filter in which color values of pixels are treated as 3-component vectors. Vector median filters are computationally expensive; for a window size of n x n, each of the n(sup 2) vectors has to be compared with other n(sup 2) - 1 vectors in distances. General purpose computation on graphics processing units (GPUs) is the paradigm of utilizing high-performance many-core GPU architectures for computation tasks that are normally handled by CPUs. In this work. NVIDIA's Compute Unified Device Architecture (CUDA) paradigm is used to accelerate vector median filtering. which has to the best of our knowledge never been done before. The performance of GPU accelerated vector median filter is compared to that of the CPU and MPI-based versions for different image and window sizes, Initial findings of the study showed 100x improvement of performance of vector median filter implementation on GPUs over CPU implementations and further speed-up is expected after more extensive optimizations of the GPU algorithm .

  2. 3-D Vector Flow Imaging

    DEFF Research Database (Denmark)

    Holbek, Simon

    For the last decade, the field of ultrasonic vector flow imaging has gotten an increasingly attention, as the technique offers a variety of new applications for screening and diagnostics of cardiovascular pathologies. The main purpose of this PhD project was therefore to advance the field of 3-D...... ultrasonic vector flow estimation and bring it a step closer to a clinical application. A method for high frame rate 3-D vector flow estimation in a plane using the transverse oscillation method combined with a 1024 channel 2-D matrix array is presented. The proposed method is validated both through phantom......, if this significant reduction in the element count can still provide precise and robust 3-D vector flow estimates in a plane. The study concludes that the RC array is capable of estimating precise 3-D vector flow both in a plane and in a volume, despite the low channel count. However, some inherent new challenges...

  3. Listeria monocytogenes as a vector for anti-cancer therapies.

    LENUS (Irish Health Repository)

    Tangney, Mark

    2012-01-31

    The intracellular pathogen Listeria monocytogenes represents a promising therapeutic vector for the delivery of DNA, RNA or protein to cancer cells or to prime immune responses against tumour-specific antigens. A number of biological properties make L. monocytogenes a promising platform for development as a vector for either gene therapy or as an anti-cancer vaccine vector. L. monocytogenes is particularly efficient in mediating internalization into host cells. Once inside cells, the bacterium produces specific virulence factors which lyse the vaculolar membrane and allow escape into the cytoplasm. Once in the cytosol, L. monocytogenes is capable of actin-based motility and cell-to-cell spread without an extracellular phase. The cytoplasmic location of L. monocytogenes is significant as this potentiates entry of antigens into the MHC Class I antigen processing pathway leading to priming of specific CD8(+) T cell responses. The cytoplasmic location is also beneficial for the delivery of DNA (bactofection) by L. monocytogenes whilst cell-to-cell spread may facilitate access of the vector to cells throughout the tumour. Several preclinical studies have demonstrated the ability of L. monocytogenes for intracellular gene or protein delivery in vitro and in vivo, and this vector has also displayed safety and efficacy in clinical trial. Here, we review the features of the L. monocytogenes host-pathogen interaction that make this bacterium such an attractive candidate with which to induce appropriate therapeutic responses. We focus primarily upon work that has led to attenuation of the pathogen, demonstrated DNA, RNA or protein delivery to tumour cells as well as research that shows the efficacy of L. monocytogenes as a vector for tumour-specific vaccine delivery.

  4. Emerging vector borne diseases – incidence through vectors

    Directory of Open Access Journals (Sweden)

    Sara eSavic

    2014-12-01

    Full Text Available Vector borne diseases use to be a major public health concern only in tropical and subtropical areas, but today they are an emerging threat for the continental and developed countries also. Nowdays, in intercontinetal countries, there is a struggle with emerging diseases which have found their way to appear through vectors. Vector borne zoonotic diseases occur when vectors, animal hosts, climate conditions, pathogens and susceptible human population exist at the same time, at the same place. Global climate change is predicted to lead to an increase in vector borne infectious diseases and disease outbreaks. It could affect the range and popultion of pathogens, host and vectors, transmission season, etc. Reliable surveilance for diseases that are most likely to emerge is required. Canine vector borne diseases represent a complex group of diseases including anaplasmosis, babesiosis, bartonellosis, borreliosis, dirofilariosis, erlichiosis, leishmaniosis. Some of these diseases cause serious clinical symptoms in dogs and some of them have a zoonotic potential with an effect to public health. It is expected from veterinarians in coordination with medical doctors to play a fudamental role at primeraly prevention and then treatment of vector borne diseases in dogs. The One Health concept has to be integrated into the struggle against emerging diseases.During a four year period, from 2009-2013, a total number of 551 dog samples were analysed for vector borne diseases (borreliosis, babesiosis, erlichiosis, anaplasmosis, dirofilariosis and leishmaniasis in routine laboratory work. The analysis were done by serological tests – ELISA for borreliosis, dirofilariosis and leishmaniasis, modified Knott test for dirofilariosis and blood smear for babesiosis, erlichiosis and anaplasmosis. This number of samples represented 75% of total number of samples that were sent for analysis for different diseases in dogs. Annually, on avarege more then half of the samples

  5. Predicting siRNA efficacy based on multiple selective siRNA representations and their combination at score level

    Science.gov (United States)

    He, Fei; Han, Ye; Gong, Jianting; Song, Jiazhi; Wang, Han; Li, Yanwen

    2017-03-01

    Small interfering RNAs (siRNAs) may induce to targeted gene knockdown, and the gene silencing effectiveness relies on the efficacy of the siRNA. Therefore, the task of this paper is to construct an effective siRNA prediction method. In our work, we try to describe siRNA from both quantitative and qualitative aspects. For quantitative analyses, we form four groups of effective features, including nucleotide frequencies, thermodynamic stability profile, thermodynamic of siRNA-mRNA interaction, and mRNA related features, as a new mixed representation, in which thermodynamic of siRNA-mRNA interaction is introduced to siRNA efficacy prediction for the first time to our best knowledge. And then an F-score based feature selection is employed to investigate the contribution of each feature and remove the weak relevant features. Meanwhile, we encode the siRNA sequence and existed empirical design rules as a qualitative siRNA representation. These two kinds of siRNA representations are combined to predict siRNA efficacy by supported Vector Regression (SVR) at score level. The experimental results indicate that our method may select the features with powerful discriminative ability and make the two kinds of siRNA representations work at full capacity. The prediction results also demonstrate that our method can outperform other popular siRNA efficacy prediction algorithms.

  6. Chikungunya virus and its mosquito vectors.

    Science.gov (United States)

    Higgs, Stephen; Vanlandingham, Dana

    2015-04-01

    Chikungunya virus (CHIKV), a mosquito-borne alphavirus of increasing public health significance, has caused large epidemics in Africa and the Indian Ocean basin; now it is spreading throughout the Americas. The primary vectors of CHIKV are Aedes (Ae.) aegypti and, after the introduction of a mutation in the E1 envelope protein gene, the highly anthropophilic and geographically widespread Ae. albopictus mosquito. We review here research efforts to characterize the viral genetic basis of mosquito-vector interactions, the use of RNA interference and other strategies for the control of CHIKV in mosquitoes, and the potentiation of CHIKV infection by mosquito saliva. Over the past decade, CHIKV has emerged on a truly global scale. Since 2013, CHIKV transmission has been reported throughout the Caribbean region, in North America, and in Central and South American countries, including Brazil, Columbia, Costa Rica, El Salvador, French Guiana, Guatemala, Guyana, Nicaragua, Panama, Suriname, and Venezuela. Closing the gaps in our knowledge of driving factors behind the rapid geographic expansion of CHIKV should be considered a research priority. The abundance of multiple primate species in many of these countries, together with species of mosquito that have never been exposed to CHIKV, may provide opportunities for this highly adaptable virus to establish sylvatic cycles that to date have not been seen outside of Africa. The short-term and long-term ecological consequences of such transmission cycles, including the impact on wildlife and people living in these areas, are completely unknown.

  7. Chikungunya Virus–Vector Interactions

    Directory of Open Access Journals (Sweden)

    Lark L. Coffey

    2014-11-01

    Full Text Available Chikungunya virus (CHIKV is a mosquito-borne alphavirus that causes chikungunya fever, a severe, debilitating disease that often produces chronic arthralgia. Since 2004, CHIKV has emerged in Africa, Indian Ocean islands, Asia, Europe, and the Americas, causing millions of human infections. Central to understanding CHIKV emergence is knowledge of the natural ecology of transmission and vector infection dynamics. This review presents current understanding of CHIKV infection dynamics in mosquito vectors and its relationship to human disease emergence. The following topics are reviewed: CHIKV infection and vector life history traits including transmission cycles, genetic origins, distribution, emergence and spread, dispersal, vector competence, vector immunity and microbial interactions, and co-infection by CHIKV and other arboviruses. The genetics of vector susceptibility and host range changes, population heterogeneity and selection for the fittest viral genomes, dual host cycling and its impact on CHIKV adaptation, viral bottlenecks and intrahost diversity, and adaptive constraints on CHIKV evolution are also discussed. The potential for CHIKV re-emergence and expansion into new areas and prospects for prevention via vector control are also briefly reviewed.

  8. Stable piecewise polynomial vector fields

    Directory of Open Access Journals (Sweden)

    Claudio Pessoa

    2012-09-01

    Full Text Available Let $N={y>0}$ and $S={y<0}$ be the semi-planes of $mathbb{R}^2$ having as common boundary the line $D={y=0}$. Let $X$ and $Y$ be polynomial vector fields defined in $N$ and $S$, respectively, leading to a discontinuous piecewise polynomial vector field $Z=(X,Y$. This work pursues the stability and the transition analysis of solutions of $Z$ between $N$ and $S$, started by Filippov (1988 and Kozlova (1984 and reformulated by Sotomayor-Teixeira (1995 in terms of the regularization method. This method consists in analyzing a one parameter family of continuous vector fields $Z_{epsilon}$, defined by averaging $X$ and $Y$. This family approaches $Z$ when the parameter goes to zero. The results of Sotomayor-Teixeira and Sotomayor-Machado (2002 providing conditions on $(X,Y$ for the regularized vector fields to be structurally stable on planar compact connected regions are extended to discontinuous piecewise polynomial vector fields on $mathbb{R}^2$. Pertinent genericity results for vector fields satisfying the above stability conditions are also extended to the present case. A procedure for the study of discontinuous piecewise vector fields at infinity through a compactification is proposed here.

  9. Chikungunya Virus–Vector Interactions

    Science.gov (United States)

    Coffey, Lark L.; Failloux, Anna-Bella; Weaver, Scott C.

    2014-01-01

    Chikungunya virus (CHIKV) is a mosquito-borne alphavirus that causes chikungunya fever, a severe, debilitating disease that often produces chronic arthralgia. Since 2004, CHIKV has emerged in Africa, Indian Ocean islands, Asia, Europe, and the Americas, causing millions of human infections. Central to understanding CHIKV emergence is knowledge of the natural ecology of transmission and vector infection dynamics. This review presents current understanding of CHIKV infection dynamics in mosquito vectors and its relationship to human disease emergence. The following topics are reviewed: CHIKV infection and vector life history traits including transmission cycles, genetic origins, distribution, emergence and spread, dispersal, vector competence, vector immunity and microbial interactions, and co-infection by CHIKV and other arboviruses. The genetics of vector susceptibility and host range changes, population heterogeneity and selection for the fittest viral genomes, dual host cycling and its impact on CHIKV adaptation, viral bottlenecks and intrahost diversity, and adaptive constraints on CHIKV evolution are also discussed. The potential for CHIKV re-emergence and expansion into new areas and prospects for prevention via vector control are also briefly reviewed. PMID:25421891

  10. Vector control of induction machines

    CERN Document Server

    Robyns, Benoit

    2012-01-01

    After a brief introduction to the main law of physics and fundamental concepts inherent in electromechanical conversion, ""Vector Control of Induction Machines"" introduces the standard mathematical models for induction machines - whichever rotor technology is used - as well as several squirrel-cage induction machine vector-control strategies. The use of causal ordering graphs allows systematization of the design stage, as well as standardization of the structure of control devices. ""Vector Control of Induction Machines"" suggests a unique approach aimed at reducing parameter sensitivity for

  11. Vector fields on nonorientable surfaces

    Directory of Open Access Journals (Sweden)

    Dorin Ghisa

    2003-01-01

    Full Text Available A one-to-one correspondence is established between the germs of functions and tangent vectors on a NOS X and the bi-germs of functions, respectively, elementary fields of tangent vectors (EFTV on the orientable double cover of X. Some representation theorems for the algebra of germs of functions, the tangent space at an arbitrary point of X, and the space of vector fields on X are proved by using a symmetrisation process. An example related to the normal derivative on the border of the Möbius strip supports the nontriviality of the concepts introduced in this paper.

  12. On the Witt vector Frobenius

    DEFF Research Database (Denmark)

    Davis, Christopher James; Kedlaya, Kiran

    2014-01-01

    We study the kernel and cokernel of the Frobenius map on the p-typical Witt vectors of a commutative ring, not necessarily of characteristic p. We give many equivalent conditions to surjectivity of the Frobenius map on both finite and infinite length Witt vectors. In particular, surjectivity...... on finite Witt vectors turns out to be stable under certain integral extensions; this provides a clean formulation of a strong generalization of Faltings’s almost purity theorem from p-adic Hodge theory, incorporating recent improvements by Kedlaya–Liu and by Scholze....

  13. Vector boson scattering at CLIC

    Energy Technology Data Exchange (ETDEWEB)

    Kilian, Wolfgang; Fleper, Christian [Department Physik, Universitaet Siegen, 57068 Siegen (Germany); Reuter, Juergen [DESY Theory Group, 22603 Hamburg (Germany); Sekulla, Marco [Institut fuer Theoretische Physik, Karlsruher Institut fuer Technologie, 76131 Karlsruhe (Germany)

    2016-07-01

    Linear colliders operating in a range of multiple TeV are able to investigate the details of vector boson scattering and electroweak symmetry breaking. We calculate cross sections with the Monte Carlo generator WHIZARD for vector boson scattering processes at the future linear e{sup +} e{sup -} collider CLIC. By finding suitable cuts, the vector boson scattering signal processes are isolated from the background. Finally, we are able to determine exclusion sensitivities on the non-Standard Model parameters of the relevant dimension eight operators.

  14. Synthetic Aperture Vector Flow Imaging

    DEFF Research Database (Denmark)

    Oddershede, Niels

    2008-01-01

    of the thesis considers a method for estimating the two-dimensional velocity vector within the image plane. This method, called synthetic aperture vector flow imaging, is first shortly reviewed. The main contribution of this work is partly an analysis of the method with respect to focusing effects, motion...... estimation. The method can be used for increasing the frame rate of color flow maps or alternatively for a new imaging modality entitled quadroplex imaging, featuring a color flow map and two independent spectrograms at a high frame rate. The second is an alternative method for ultrasonic vector velocity...

  15. On the Witt vector Frobenius

    DEFF Research Database (Denmark)

    Davis, Christopher James; Kedlaya, Kiran

    2014-01-01

    We study the kernel and cokernel of the Frobenius map on the p-typical Witt vectors of a commutative ring, not necessarily of characteristic p. We give many equivalent conditions to surjectivity of the Frobenius map on both finite and infinite length Witt vectors. In particular, surjectivity...... on finite Witt vectors turns out to be stable under certain integral extensions; this provides a clean formulation of a strong generalization of Faltings’s almost purity theorem from p-adic Hodge theory, incorporating recent improvements by Kedlaya–Liu and by Scholze....

  16. RNA Interference Targeting Leptin Gene Effect on Hepatic Stellate Cells

    Institute of Scientific and Technical Information of China (English)

    XUE Xiulan; LIN Jusheng; SONG Yuhu; SUN Xuemei; ZHOU Hejun

    2005-01-01

    To construct the specific siRNA expression vectors and investigate their effect on leptin and collagen I in HSC, which provide a new approach to the prevent and treat hepatic fibrosis. The five siRNAs against leptin gene were transcript synthesized intracellularly by expression templates of plasmid vector psiRNA-hH1neo. The recombinant leptin siRNA plasmid vectors could express in eukaryocyte , and then to evaluate them by using enzyme cutting and sequencing. The recombinant plasmids were transfected into HSCs using Lipofectamine methods respectively. The cells were selected after growing in DMEM containing 300 μg/mL G418 for about 4 weeks. Gene expression of leptin and collagen I were showed by Western blot analysis and reverse transcription polymerase chain reaction (RT-PCR). Identification by enzyme cutting and sequencing showed that the leptin siRNA expression vectors were constructed successfully, and leptin siRNA could inhibit the leptin and collagen I gene expression effectively. It was concluded that RNA interference-mediated silencing of leptin gene diminished leptin and collagen I gene expression in HSCs. Furthermore, attenuated the extracellular matrix over-deposition at the same time. Leptin gene is ideal targets of gene therapy for liver fibrosis.

  17. In vitro and in vivo characterization of microRNA-targeted alphavirus replicon and helper RNAs.

    Science.gov (United States)

    Kamrud, Kurt I; Coffield, V McNeil; Owens, Gary; Goodman, Christin; Alterson, Kim; Custer, Max; Murphy, Michael A; Lewis, Whitney; Timberlake, Sarah; Wansley, Elizabeth K; Berglund, Peter; Smith, Jonathan

    2010-08-01

    Alphavirus-based replicon vector systems (family Togaviridae) have been developed as expression vectors with demonstrated potential in vaccine development against both infectious diseases and cancer. The single-cycle nature of virus-like replicon particles (VRP), generated by supplying the structural proteins from separate replicable helper RNAs, is an attractive safety component of these systems. MicroRNAs (miRNAs) have emerged as important cellular RNA regulation elements. Recently, miRNAs have been employed as a mechanism to attenuate or restrict cellular tropism of replication-competent viruses, such as oncolytic adenoviruses, vesicular stomatitis virus, and picornaviruses as well as nonreplicating lentiviral and adenoviral vectors. Here, we describe the incorporation of miRNA-specific target sequences into replicable alphavirus helper RNAs that are used in trans to provide the structural proteins required for VRP production. VRP were found to be efficiently produced using miRNA-targeted helper RNAs if miRNA-specific inhibitors were introduced into cells during VRP production. In the absence of such inhibitors, cellular miRNAs were capable of downregulating helper RNA replication in vitro. When miRNA targets were incorporated into a replicon RNA, cellular miRNAs were capable of downregulating replicon RNA replication upon delivery of VRP into animals, demonstrating activity in vivo. These data provide the first example of miRNA-specific repression of alphavirus replicon and helper RNA replication and demonstrate the feasibility of miRNA targeting of expression vector helper functions that are provided in trans.

  18. Triggering of RNA interference with RNA-RNA, RNA-DNA, and DNA-RNA nanoparticles.

    Science.gov (United States)

    Afonin, Kirill A; Viard, Mathias; Kagiampakis, Ioannis; Case, Christopher L; Dobrovolskaia, Marina A; Hofmann, Jen; Vrzak, Ashlee; Kireeva, Maria; Kasprzak, Wojciech K; KewalRamani, Vineet N; Shapiro, Bruce A

    2015-01-27

    Control over cellular delivery of different functionalities and their synchronized activation is a challenging task. We report several RNA and RNA/DNA-based nanoparticles designed to conditionally activate the RNA interference in various human cells. These nanoparticles allow precise control over their formulation, stability in blood serum, and activation of multiple functionalities. Importantly, interferon and pro-inflammatory cytokine activation assays indicate the significantly lower responses for DNA nanoparticles compared to the RNA counterparts, suggesting greater potential of these molecules for therapeutic use.

  19. Alternative RNA splicing of KSHV ORF57 produces two different RNA isoforms.

    Science.gov (United States)

    Majerciak, Vladimir; Zheng, Zhi-Ming

    2016-01-15

    In lytically infected B cells Kaposi sarcoma-associated herpesvirus (KSHV) ORF57 gene encodes two RNA isoforms by alternative splicing of its pre-mRNA, which contains a small, constitutive intron in its 5' half and a large, suboptimal intron in its 3's half. The RNA1 isoform encodes full-length ORF57 and is a major isoform derived from splicing of the constitutive small intron, but retaining the suboptimal large intron as the coding region. A small fraction (splicing to produce a smaller non-coding RNA2 due to lack of a translational termination codon. Both RNAs are cleaved and polyadenylated at the same cleavage site CS83636. The insertion of ORF57 RNA1 into a restriction cutting site in certain mammalian expression vectors activates splicing of the subopitmal intron and produces a truncated ORF57 protein.

  20. HER-2/neu·siRNA表达载体的构建及对人乳腺癌细胞株的影响%Vector construction and silencing effects of siRNA to HER-2/neu gene of human breast cancer cell line SK-BR-3

    Institute of Scientific and Technical Information of China (English)

    万光霞; 林辉; 刘浔阳

    2010-01-01

    目的:探讨siRNA 对人乳腺癌细胞株SK-BR-3 的HER-2/neu基因表达的影响.方法:以HER-2/neu mRNA 序列为模板设计合成2对siRNA 序列,构建pGenesil-1-HER-2/neu siRNA 重组质粒,转化感受态的大肠杆菌,质粒酶切、测序鉴定.转染SK-BR-3 细胞48 h后,提取RNA 进行RT-PCR,采用方差分析(ANOVA),分析RNA 干扰效应.结果:成功构建了pGenesil-1-HER-2/neu siRNA 重组质粒,成功转染SK-BR-3 细胞.重组质粒抑制HER-2/neu基因的表达接近54.45 %( P =0.000).结论: HER-2/neu siRNA 重组质粒明显下调HER-2/neu 基因在乳腺癌细胞中的表达.

  1. Acoustic vector sensor signal processing

    Institute of Scientific and Technical Information of China (English)

    SUN Guiqing; LI Qihu; ZHANG Bin

    2006-01-01

    Acoustic vector sensor simultaneously, colocately and directly measures orthogonal components of particle velocity as well as pressure at single point in acoustic field so that is possible to improve performance of traditional underwater acoustic measurement devices or detection systems and extends new ideas for solving practical underwater acoustic engineering problems. Although acoustic vector sensor history of appearing in underwater acoustic area is no long, but with huge and potential military demands, acoustic vector sensor has strong development trend in last decade, it is evolving into a one of important underwater acoustic technology. Under this background, we try to review recent progress in study on acoustic vector sensor signal processing, such as signal detection, DOA estimation, beamforming, and so on.

  2. Introduction to matrices and vectors

    CERN Document Server

    Schwartz, Jacob T

    2001-01-01

    In this concise undergraduate text, the first three chapters present the basics of matrices - in later chapters the author shows how to use vectors and matrices to solve systems of linear equations. 1961 edition.

  3. GRE Enzymes for Vector Analysis

    Data.gov (United States)

    U.S. Environmental Protection Agency — Microbial enzyme data that were collected during the 2004-2006 EMAP-GRE program. These data were then used by Moorhead et al (2016) in their ecoenzyme vector...

  4. All optical vector magnetometer Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This Phase I research project will investigate a novel method of operating an atomic magnetometer to simultaneously measure total magnetic fields and vector magnetic...

  5. Unsupervised learning of binary vectors

    Science.gov (United States)

    Copelli Lopes da Silva, Mauro

    In this thesis, unsupervised learning of binary vectors from data is studied using methods from Statistical Mechanics of disordered systems. In the model, data vectors are distributed according to a single symmetry-breaking direction. The aim of unsupervised learning is to provide a good approximation to this direction. The difference with respect to previous studies is the knowledge that this preferential direction has binary components. It is shown that sampling from the posterior distribution (Gibbs learning) leads, for general smooth distributions, to an exponentially fast approach to perfect learning in the asymptotic limit of large number of examples. If the distribution is non-smooth, then first order phase transitions to perfect learning are expected. In the limit of poor performance, a second order phase transition ("retarded learning") is predicted to occur if the data distribution is not biased. Using concepts from Bayesian inference, the center of mass of the Gibbs ensemble is shown to have maximal average (Bayes-optimal) performance. This upper bound for continuous vectors is extended to a discrete space, resulting in the clipped center of mass of the Gibbs ensemble having maximal average performance among the binary vectors. To calculate the performance of this best binary vector, the geometric properties of the center of mass of binary vectors are studied. The surprising result is found that the center of mass of infinite binary vectors which obey some simple constraints, is again a binary vector. When disorder is taken into account in the calculation, however, a vector with continuous components is obtained. The performance of the best binary vector is calculated and shown to always lie above that of Gibbs learning and below the Bayes-optimal performance. Making use of a variational approach under the replica symmetric ansatz, an optimal potential is constructed in the limits of zero temperature and mutual overlap 1. Minimization of this potential

  6. RAID: a comprehensive resource for human RNA-associated (RNA-RNA/RNA-protein) interaction.

    Science.gov (United States)

    Zhang, Xiaomeng; Wu, Deng; Chen, Liqun; Li, Xiang; Yang, Jinxurong; Fan, Dandan; Dong, Tingting; Liu, Mingyue; Tan, Puwen; Xu, Jintian; Yi, Ying; Wang, Yuting; Zou, Hua; Hu, Yongfei; Fan, Kaili; Kang, Juanjuan; Huang, Yan; Miao, Zhengqiang; Bi, Miaoman; Jin, Nana; Li, Kongning; Li, Xia; Xu, Jianzhen; Wang, Dong

    2014-07-01

    Transcriptomic analyses have revealed an unexpected complexity in the eukaryote transcriptome, which includes not only protein-coding transcripts but also an expanding catalog of noncoding RNAs (ncRNAs). Diverse coding and noncoding RNAs (ncRNAs) perform functions through interaction with each other in various cellular processes. In this project, we have developed RAID (http://www.rna-society.org/raid), an RNA-associated (RNA-RNA/RNA-protein) interaction database. RAID intends to provide the scientific community with all-in-one resources for efficient browsing and extraction of the RNA-associated interactions in human. This version of RAID contains more than 6100 RNA-associated interactions obtained by manually reviewing more than 2100 published papers, including 4493 RNA-RNA interactions and 1619 RNA-protein interactions. Each entry contains detailed information on an RNA-associated interaction, including RAID ID, RNA/protein symbol, RNA/protein categories, validated method, expressing tissue, literature references (Pubmed IDs), and detailed functional description. Users can query, browse, analyze, and manipulate RNA-associated (RNA-RNA/RNA-protein) interaction. RAID provides a comprehensive resource of human RNA-associated (RNA-RNA/RNA-protein) interaction network. Furthermore, this resource will help in uncovering the generic organizing principles of cellular function network.

  7. Decays of the vector glueball

    CERN Document Server

    Giacosa, Francesco; Janowski, Stanislaus

    2016-01-01

    We calculate two- and three-body decays of the (lightest) vector glueball into (pseudo)scalar, (axial-)vector, as well as pseudovector and excited vector mesons. By setting the mass of this yet hypothetical vector glueball to 3.8 GeV as predicted by Lattice QCD, many branching ratios can be computed and represent a parameter-free prediction of our approach. We find that the decay mode $\\omega\\pi\\pi$ should be one of the largest (both through the decay chain $\\mathcal{O}\\rightarrow b_{1}\\pi\\rightarrow$ $\\omega\\pi\\pi$ and through the direct coupling $\\mathcal{O}\\rightarrow\\omega\\pi\\pi$)$.$ Similarly, the (direct and indirect) decay into $\\pi KK^{\\ast}(892)$ is sizable. Moreover, the decays into $\\rho\\pi$ and $K^{\\ast}(892)K$ are, although subleading, possible and could play a role in explaining the $\\rho\\pi$ puzzle of the charmonium state $\\psi(2S)$ thank to a (small) mixing with the vector glueball. The vector glueball can be directly formed at the ongoing BESIII experiment as well as at the future PANDA exper...

  8. Handling S/MAR vectors.

    Science.gov (United States)

    Hagedorn, Claudia; Baiker, Armin; Postberg, Jan; Ehrhardt, Anja; Lipps, Hans J

    2012-06-01

    Nonviral episomal vectors represent attractive alternatives to currently used virus-based expression systems. In the late 1990s, it was shown that a plasmid containing an expression cassette linked to a scaffold/matrix attached region (S/MAR) replicates as a low copy number episome in all cell lines tested, as well as primary cells, and can be used for the genetic modification of higher animals. Once established in the cell, the S/MAR vector replicates early during S-phase and, in the absence of selection, is stably retained in the cells for an unlimited period of time. This vector can therefore be regarded as a minimal model system for studying the epigenetic regulation of replication and functional nuclear architecture. In theory, this construct represents an almost "ideal" expression system for gene therapy. In practice, S/MAR-based vectors stably modify mammalian cells with efficiencies far below those of virus-based constructs. Consequently, they have not yet found application in gene therapy trials. Furthermore, S/MAR vector systems are not trivial to handle and several critical technical issues have to be considered when modifying these vectors for various applications.

  9. Recent innovations in mRNA vaccines.

    Science.gov (United States)

    Ulmer, Jeffrey B; Geall, Andrew J

    2016-08-01

    Nucleic acid-based vaccines are being developed as a means to combine the positive attributes of both live-attenuated and subunit vaccines. Viral vectors and plasmid DNA vaccines have been extensively evaluated in human clinical trials and have been shown to be safe and immunogenic, although none have yet been licensed for human use. Recently, mRNA based vaccines have emerged as an alternative approach. They promise the flexibility of plasmid DNA vaccines, without the need for electroporation, but with enhanced immunogenicity and safety. In addition, they avoid the limitations of anti-vector immunity seen with viral vectors, and can be dosed repeatedly. This review highlights the key papers published over the past few years and summarizes prospects for the near future.

  10. Tubular structure induced by a plant virus facilitates viral spread in its vector insect.

    Directory of Open Access Journals (Sweden)

    Qian Chen

    Full Text Available Rice dwarf virus (RDV replicates in and is transmitted by a leafhopper vector in a persistent-propagative manner. Previous cytopathologic and genetic data revealed that tubular structures, constructed by the nonstructural viral protein Pns10, contain viral particles and are directly involved in the intercellular spread of RDV among cultured leafhopper cells. Here, we demonstrated that RDV exploited these virus-containing tubules to move along actin-based microvilli of the epithelial cells and muscle fibers of visceral muscle tissues in the alimentary canal, facilitating the spread of virus in the body of its insect vector leafhoppers. In cultured leafhopper cells, the knockdown of Pns10 expression due to RNA interference (RNAi induced by synthesized dsRNA from Pns10 gene strongly inhibited tubule formation and prevented the spread of virus among insect vector cells. RNAi induced after ingestion of dsRNA from Pns10 gene strongly inhibited formation of tubules, preventing intercellular spread and transmission of the virus by the leafhopper. All these results, for the first time, show that a persistent-propagative virus exploits virus-containing tubules composed of a nonstructural viral protein to traffic along actin-based cellular protrusions, facilitating the intercellular spread of the virus in the vector insect. The RNAi strategy and the insect vector cell culture provide useful tools to investigate the molecular mechanisms enabling efficient transmission of persistent-propagative plant viruses by vector insects.

  11. 3' Noncoding Region Construction of GHR Gene-luciferase Report Vector and Valuation

    Institute of Scientific and Technical Information of China (English)

    Jie Jing; Men Jing; Wang Chun-mei; Gao Xue-jun; Li Qing-zhang

    2012-01-01

    To analyze miR-139 target sites in 3' UTR of GHR gene in dairy cow mammary gland, a GHR 3' UTR- luciferase reporter vector was constructed and the effect of miRNA on its activity was evaluated in dairy cow mammary gland epithelial cells (DCMECs). The miR-139 targeting GHR 3' UTR was predicted by Target Scan 5.1 software, 3' UTR fragment of GHR was amplified by PCR from RNA of DCMECs. PCR products were cloned into Spe Ⅰ/Hind Ⅱ modified pMIR-Report vector. The luciferase reporter vector and miRNA eukaryotic expression vector were transferred into DCMECs using lipofectamine 2000 transfection reagent. The dualluciferase reporter assay system was used to quantitiate the reporter activity. The results showed that a 107 bp 3' UTR fragment of GHR gene was successfully cloned into the pMIR-Report vector, which authenticated by Spe Ⅰ/Hind Ⅲ digestion and DNA sequencing. The luciferase activity of reporter construction treated with miR-139 decreased 20.87% compared with the control group. It was concluded that the GHR3' UTR-luciferase reporter vector had been successfully constructed. The luciferase activity of the reporter could be suppressed by miR- 139.

  12. Are Bred Vectors The Same As Lyapunov Vectors?

    Science.gov (United States)

    Kalnay, E.; Corazza, M.; Cai, M.

    Regional loss of predictability is an indication of the instability of the underlying flow, where small errors in the initial conditions (or imperfections in the model) grow to large amplitudes in finite times. The stability properties of evolving flows have been studied using Lyapunov vectors (e.g., Alligood et al, 1996, Ott, 1993, Kalnay, 2002), singular vectors (e.g., Lorenz, 1965, Farrell, 1988, Molteni and Palmer, 1993), and, more recently, with bred vectors (e.g., Szunyogh et al, 1997, Cai et al, 2001). Bred vectors (BVs) are, by construction, closely related to Lyapunov vectors (LVs). In fact, after an infinitely long breeding time, and with the use of infinitesimal ampli- tudes, bred vectors are identical to leading Lyapunov vectors. In practical applications, however, bred vectors are different from Lyapunov vectors in two important ways: a) bred vectors are never globally orthogonalized and are intrinsically local in space and time, and b) they are finite-amplitude, finite-time vectors. These two differences are very significant in a dynamical system whose size is very large. For example, the at- mosphere is large enough to have "room" for several synoptic scale instabilities (e.g., storms) to develop independently in different regions (say, North America and Aus- tralia), and it is complex enough to have several different possible types of instabilities (such as barotropic, baroclinic, convective, and even Brownian motion). Bred vectors share some of their properties with leading LVs (Corazza et al, 2001a, 2001b, Toth and Kalnay, 1993, 1997, Cai et al, 2001). For example, 1) Bred vectors are independent of the norm used to define the size of the perturba- tion. Corazza et al. (2001) showed that bred vectors obtained using a potential enstro- phy norm were indistinguishable from bred vectors obtained using a streamfunction squared norm, in contrast with singular vectors. 2) Bred vectors are independent of the length of the rescaling period as long as the

  13. Newcastle disease virus vectored vaccines as bivalent or antigen delivery vaccines

    Science.gov (United States)

    2017-01-01

    Recent advances in reverse genetics techniques make it possible to manipulate the genome of RNA viruses such as Newcastle disease virus (NDV). Several NDV vaccine strains have been used as vaccine vectors in poultry, mammals, and humans to express antigens of different pathogens. The safety, immunogenicity, and protective efficacy of these NDV-vectored vaccines have been evaluated in pre-clinical and clinical studies. The vaccines are safe in mammals, humans, and poultry. Bivalent NDV-vectored vaccines against pathogens of economic importance to the poultry industry have been developed. These bivalent vaccines confer solid protective immunity against NDV and other foreign antigens. In most cases, NDV-vectored vaccines induce strong local and systemic immune responses against the target foreign antigen. This review summarizes the development of NDV-vectored vaccines and their potential use as a base for designing other effective vaccines for veterinary and human use. PMID:28775971

  14. Dual-function vector for protein expression in both mammalian cells and Xenopus laevis oocytes

    DEFF Research Database (Denmark)

    Jespersen, Thomas; Grunnet, M; Angelo, K;

    2002-01-01

    will often engage both oocytes and mammalian cells. Efficient expression of a protein in both systems have thus far only been possible by subcloning the cDNA into two different vectors because several different molecular requirements should be fulfilled to obtain a high protein level in both mammalian cells...... and oocytes. To address this problem, we have constructed a plasmid vector, pXOOM, that can function as a template for expression in both oocytes and mammalian cells. By including all the necessary RNA stability elements for oocyte expression in a standard mammalian expression vector, we have obtained a dual......-function vector capable of supporting protein production in both Xenopus oocytes and CHO-K1 cells at an expression level equivalent to the levels obtained with vectors optimized for either oocyte or mammalian expression. Our functional studies have been performed with hERGI, KCNQ4, and Kv1.3 potassium channels....

  15. Properties and use of novel replication-competent vectors based on Semliki Forest virus

    Directory of Open Access Journals (Sweden)

    Lulla Valeria

    2009-03-01

    Full Text Available Abstract Background Semliki Forest virus (SFV has a positive strand RNA genome and infects different cells of vertebrates and invertebrates. The 5' two-thirds of the genome encodes non-structural proteins that are required for virus replication and synthesis of subgenomic (SG mRNA for structural proteins. SG-mRNA is generated by internal initiation at the SG-promoter that is located at the complementary minus-strand template. Different types of expression systems including replication-competent vectors, which represent alphavirus genomes with inserted expression units, have been developed. The replication-competent vectors represent useful tools for studying alphaviruses and have potential therapeutic applications. In both cases, the properties of the vector, such as its genetic stability and expression level of the protein of interest, are important. Results We analysed 14 candidates of replication-competent vectors based on the genome of an SFV4 isolate that contained a duplicated SG promoter or an internal ribosomal entry site (IRES-element controlled marker gene. It was found that the IRES elements and the minimal -21 to +5 SG promoter were non-functional in the context of these vectors. The efficient SG promoters contained at least 26 residues upstream of the start site of SG mRNA. The insertion site of the SG promoter and its length affected the genetic stability of the vectors, which was always higher when the SG promoter was inserted downstream of the coding region for structural proteins. The stability also depended on the conditions used for vector propagation. A procedure based on the in vitro transcription of ligation products was used for generation of replication-competent vector-based expression libraries that contained hundreds of thousands of different genomes, and maintained genetic diversity and the ability to express inserted genes over five passages in cell culture. Conclusion The properties of replication-competent vectors

  16. GrowthinhibitioninducedbyshorthairpinRNA tosilencesurvivingeneinhumanpancreatic cancercells

    Institute of Scientific and Technical Information of China (English)

    Yong-Mei Shen; Xiao-Chun Yang; Miao-Li Song; Chen-Hao Qin; Chen Yang; Yi-Hui Sun

    2010-01-01

    BACKGROUND: Survivin is known to be overexpressed in various human malignancies, including pancreatic cancer, and mediates cancer cell proliferation and tumor growth, so the regulation of this molecule could be a new strategy for treating pancreatic cancer. In this study, short hairpin RNAs (shRNAs) speciifc to survivin were introduced into human pancreatic cancer Patu8988 cells to investigate the inhibitory effects on survivin expression and cell proliferation in vitro and in vivo. METHODS: Three kinds of shRNA speciifc to the survivin gene were designed and cloned into eukaryotic expression plasmid pGenesil-1 vector. Subsequently the recombinant plasmids were transfected into human pancreatic cancer Patu8988 cells with lipfectamineTM 2000 reagent. The mRNA and protein expressions of survivin in the transiently transfected Patu8988 cells were determined by RT-PCR, lfow cytometry, and Western blotting analysis. The proliferation inhibition rates of stably transfected Patu8988 cells were determined by MTT assay. The antitumor activities of the three kinds of survivin-shRNA plasmids were evaluated in BALB/c nude mice inoculated with Patu8988 cells and bearing human pancreatic cancer. RESULTS: The three survivin-shRNA plasmids named pGenesil-1-survivin-1, pGenesil-1-survivin-2 and pGenesil-1-survivin-1+2 (with double interfering RNA sites) were successfully constructed, and were conifrmed by restriction enzyme cutting and sequencing. At 48 hours after transfection, the expression of survivin mRNA and protein was inhibited in Patu8988 cells transfected with pGenesil-1-survivin-1, pGenesil-1-survivin-2, and pGenesil-1-survivin-1+2 when compared with that of either pGenesil-1-NC (with scrambled small interfering RNA) transfected cells or control cells (P CONCLUSIONS: shRNAs speciifc to survivin have gene silencing effects and inhibit pancreatic cancer cell proliferation. shRNA activity against survivin could be of potential value in gene therapy for pancreatic

  17. RNA chaperones encoded by RNA viruses

    Institute of Scientific and Technical Information of China (English)

    Jie Yang; Hongjie Xia; Qi Qian; Xi Zhou

    2015-01-01

    RNAs are functionally diverse macromolecules whose proper functions rely strictly upon their correct tertiary structures. However, because of their high structural flexibility, correct folding of RNAs is challenging and slow. Therefore, cells and viruses encode a variety of RNA remodeling proteins, including helicases and RNA chaperones. In RNA viruses, these proteins are believed to play pivotal roles in all the processes involving viral RNAs during the life cycle. RNA helicases have been studied extensively for decades, whereas RNA chaperones, particularly virus-encoded RNA chaperones, are often overlooked. This review describes the activities of RNA chaperones encoded by RNA viruses, particularly the ones identified and characterized in recent years, and the functions of these proteins in different steps of viral life cycles, and presents an overview of this unique group of proteins.

  18. Extracellular RNA Communication (ExRNA)

    Data.gov (United States)

    Federal Laboratory Consortium — Until recently, scientists believed RNA worked mostly inside the cell that produced it. Some types of RNA help translate genes into proteins that are necessary for...

  19. Short hairpin RNA targeting NP mRNA inhibiting Newcastle disease virus production and other viral structural mRNA transcription.

    Science.gov (United States)

    Yue, Hua; Deng, Shu; Yang, Fa-Long; Li, Ding-Fei; Fu, An-Jing; Yang, Fan; Tang, Cheng

    2009-02-01

    Newcastle disease virus (NDV), formally recognized as avian paramyxovirus 1 (APMV-1), is the etiological agent of Newcastle disease (ND), an affliction which can cause severe losses in the poultry industry. Better understanding of the molecular basis of viral structural genes involved with production should contribute significantly toward the development of improved prophylactic and therapeutic reagents to control the infection. Here we show that a short hairpin RNA (shRNA) eukaryotic expression vector targeting nucleocapsid (NP) gene of NDV can potently inhibit NDV production in both primary cells and embryonated chicken eggs. Moreover, shRNA specific for NP abolished the accumulation of not only the corresponding mRNA but also P, HN, F, M gene mRNA. The findings reveal that newly synthesized NP mRNA is essential for NDV transcription and replication, and provide a basis for the development of shRNAs as a prophylaxis and therapy for NDV infection in poultry.

  20. Containment of arthropod disease vectors.

    Science.gov (United States)

    Scott, Thomas W

    2005-01-01

    Effective containment of arthropod vectors of infectious diseases is necessary to prevent transmission of pathogens by released, infected vectors and to prevent vectors that escape from establishing populations that subsequently contribute to increased disease. Although rare, past releases illustrate what can go wrong and justify the need for guidelines that minimize risks. An overview of recommendations for insectary facilities, practices, and equipment is provided, and features of four recently published and increasingly rigorous arthropod containment levels (ACLs 1-4) are summarized. ACL-1 is appropriate for research that constitutes the lowest risk level, including uninfected arthropods or vectors that are infected with micro-organisms that do not cause disease in humans, domestic animals, or wildlife. ACL-2 is appropriate for indigenous and exotic arthropods that represent a moderate risk, including vectors infected or suspected of being infected with biosafety level (BSL)-2 infectious agents and arthropods that have been genetically modified in ways that do not significantly affect their fecundity, survival, host preference, or vector competence. ACL-3 is recommended for arthropods that are or may be infected with BSL-3 infectious agents. ACL-3 places greater emphasis on pathogen containment and more restricted access to the insectary than ACL-2. ACL-4 is intended for arthropods that are infected with the most dangerous BSL-4 infectious agents, which can cause life-threatening illness by aerosol or arthropod bite. Adherence to these guidelines will result in laboratory-based arthropod vector research that minimizes risks and results in important new contributions to applied and basic science.

  1. Black holes with vector hair

    Science.gov (United States)

    Fan, Zhong-Ying

    2016-09-01

    In this paper, we consider Einstein gravity coupled to a vector field, either minimally or non-minimally, together with a vector potential of the type V = 2{Λ}_0+1/2{m}^2{A}^2 + {γ}_4{A}^4 . For a simpler non-minimally coupled theory with Λ0 = m = γ4 = 0, we obtain both extremal and non-extremal black hole solutions that are asymptotic to Minkowski space-times. We study the global properties of the solutions and derive the first law of thermodynamics using Wald formalism. We find that the thermodynamical first law of the extremal black holes is modified by a one form associated with the vector field. In particular, due to the existence of the non-minimal coupling, the vector forms thermodynamic conjugates with the graviton mode and partly contributes to the one form modifying the first law. For a minimally coupled theory with Λ0 ≠ 0, we also obtain one class of asymptotically flat extremal black hole solutions in general dimensions. This is possible because the parameters ( m 2 , γ4) take certain values such that V = 0. In particular, we find that the vector also forms thermodynamic conjugates with the graviton mode and contributes to the corresponding first law, although the non-minimal coupling has been turned off. Thus all the extremal black hole solutions that we obtain provide highly non-trivial examples how the first law of thermodynamics can be modified by a either minimally or non-minimally coupled vector field. We also study Gauss-Bonnet gravity non-minimally coupled to a vector and obtain asymptotically flat black holes and Lifshitz black holes.

  2. Decays of the vector glueball

    Science.gov (United States)

    Giacosa, Francesco; Sammet, Julia; Janowski, Stanislaus

    2017-06-01

    We calculate two- and three-body decays of the (lightest) vector glueball into (pseudo)scalar, (axial-)vector, as well as pseudovector and excited vector mesons in the framework of a model of QCD. While absolute values of widths cannot be predicted because the corresponding coupling constants are unknown, some interesting branching ratios can be evaluated by setting the mass of the yet hypothetical vector glueball to 3.8 GeV as predicted by quenched lattice QCD. We find that the decay mode ω π π should be one of the largest (both through the decay chain O →b1π →ω π π and through the direct coupling O →ω π π ). Similarly, the (direct and indirect) decay into π K K*(892 ) is sizable. Moreover, the decays into ρ π and K*(892 )K are, although subleading, possible and could play a role in explaining the ρ π puzzle of the charmonium state ψ (2 S ) thanks to a (small) mixing with the vector glueball. The vector glueball can be directly formed at the ongoing BESIII experiment as well as at the future PANDA experiment at the FAIR facility. If the width is sufficiently small (≲100 MeV ) it should not escape future detection. It should be stressed that the employed model is based on some inputs and simplifying assumptions: the value of glueball mass (at present, the quenched lattice value is used), the lack of mixing of the glueball with other quarkonium states, and the use of few interaction terms. It then represents a first step toward the identification of the main decay channels of the vector glueball, but shall be improved when corresponding experimental candidates and/or new lattice results will be available.

  3. Low cytotoxicity fluorescent PAMAM dendrimer as gene carriers for monitoring the delivery of siRNA

    Energy Technology Data Exchange (ETDEWEB)

    Guan, Lingmei [Sichuan University, State Key Laboratory of Bio-resources and Eco-environment, The Ministry of Education, College of Life Sciences (China); Huang, Saipeng [Chinese Academy of Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Center for Molecular Sciences, Institute of Chemistry (China); Chen, Zhao [Xi’an Jiaotong University, School of Science (China); Li, Yanchao [Chinese Academy of Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Center for Molecular Sciences, Institute of Chemistry (China); Liu, Ke [Sichuan University, State Key Laboratory of Bio-resources and Eco-environment, The Ministry of Education, College of Life Sciences (China); Liu, Yang, E-mail: yliu@iccas.ac.cn; Du, Libo, E-mail: dulibo@iccas.ac.cn [Chinese Academy of Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Center for Molecular Sciences, Institute of Chemistry (China)

    2015-09-15

    Visual detection of gene vectors has attracted a great deal of attention due to the application of these vectors in monitoring and evaluating the effect of gene carriers in living cells. A non-viral vector, the fluorescent PAMAM dendrimer (F-PAMAM), was synthesized through conjugation of PAMAM dendrimers and fluorescein. In vitro and ex vivo experiments show that F-PAMAM exhibits superphotostability, low cytotoxicity and facilitates endocytosis by A549 cells. The vector has a high siRNA binding affinity and it increases the efficiency of cy5-siRNA delivery in A549 cells, in comparison with a cy5-siRNA monomer. Our results provide a new method for simultaneously monitoring the delivery of siRNA and its non-viral carriers in living cells.

  4. A NOTE ON VECTOR CASCADE ALGORITHM

    Institute of Scientific and Technical Information of China (English)

    Qiu-hui Chen; Jin-zhao Liu; Wen-sheng Zhang

    2002-01-01

    The focus of this paper is on the relationship between accuracy of multivariate refinable vector and vector cascade algorithm. We show that, if the vector cascade algorithm (1.5) with isotropic dilation converges to a vector-valued function with regularity, then the initial function must satisfy the Strang-Fix conditions.

  5. Project Physics Programmed Instruction, Vectors 1.

    Science.gov (United States)

    Harvard Univ., Cambridge, MA. Harvard Project Physics.

    This programmed instruction booklet is an interim version of instructional materials being developed by Harvard Project Physics. It is the first in a series of three booklets on vectors and covers the definitions of vectors and scalars, drawing vector quantities to scale, and negative vectors. For others in this series, see SE 015 550 and SE 015…

  6. Project Physics Programmed Instruction, Vectors 2.

    Science.gov (United States)

    Harvard Univ., Cambridge, MA. Harvard Project Physics.

    This is the second of a series of three programmed instruction booklets on vectors developed by Harvard Project Physics. It covers adding two or more vectors together, and finding a third vector that could be added to two given vectors to make a sum of zero. For other booklets in this series, see SE 015 549 and SE 015 551. (DT)

  7. The Duality on Vector Optimization Problems

    Institute of Scientific and Technical Information of China (English)

    HUANG Long-guang

    2012-01-01

    Duality framework on vector optimization problems in a locally convex topological vector space are established by using scalarization with a cone-strongly increasing function.The dualities for the scalar convex composed optimization problems and for general vector optimization problems are studied.A general approach for studying duality in vector optimization problems is presented.

  8. The biological control of disease vectors.

    Science.gov (United States)

    Okamoto, Kenichi W; Amarasekare, Priyanga

    2012-09-21

    Vector-borne diseases are common in nature and can have a large impact on humans, livestock and crops. Biological control of vectors using natural enemies or competitors can reduce vector density and hence disease transmission. However, the indirect interactions inherent in host-vector disease systems make it difficult to use traditional pest control theory to guide biological control of disease vectors. This necessitates a conceptual framework that explicitly considers a range of indirect interactions between the host-vector disease system and the vector's biological control agent. Here we conduct a comparative analysis of the efficacy of different types of biological control agents in controlling vector-borne diseases. We report three key findings. First, highly efficient predators and parasitoids of the vector prove to be effective biological control agents, but highly virulent pathogens of the vector also require a high transmission rate to be effective. Second, biocontrol agents can successfully reduce long-term host disease incidence even though they may fail to reduce long-term vector densities. Third, inundating a host-vector disease system with a natural enemy of the vector has little or no effect on reducing disease incidence, but inundating the system with a competitor of the vector has a large effect on reducing disease incidence. The comparative framework yields predictions that are useful in developing biological control strategies for vector-borne diseases. We discuss how these predictions can inform ongoing biological control efforts for host-vector disease systems.

  9. Vector-valued automorphic forms and vector bundles

    CERN Document Server

    Saber, Hicham

    2013-01-01

    For an arbitrary discrete group $\\Gamma$ and an $n$-dimensional complex representation $R$ of $\\Gamma$, we prove the existence of $n$ linearly independent vector-valued automorphic forms for $\\Gamma$ with multiplier $R$. To this end, we realize these automorphic forms as sections of a rank $n$ vector bundle attached to a 1-cocycle with coefficients in the sheaf $\\mbox{GL}(n,{\\mathcal O}_X)$, $X$ being the quotient of the Poincar\\'e half-plane by $\\Gamma$ completed with the cusps of $\\Gamma$.

  10. Implementing Bayesian Vector Autoregressions Implementing Bayesian Vector Autoregressions

    Directory of Open Access Journals (Sweden)

    Richard M. Todd

    1988-03-01

    Full Text Available Implementing Bayesian Vector Autoregressions This paper discusses how the Bayesian approach can be used to construct a type of multivariate forecasting model known as a Bayesian vector autoregression (BVAR. In doing so, we mainly explain Doan, Littermann, and Sims (1984 propositions on how to estimate a BVAR based on a certain family of prior probability distributions. indexed by a fairly small set of hyperparameters. There is also a discussion on how to specify a BVAR and set up a BVAR database. A 4-variable model is used to iliustrate the BVAR approach.

  11. Vector Encoding in Biochemical Networks

    Science.gov (United States)

    Potter, Garrett; Sun, Bo

    Encoding of environmental cues via biochemical signaling pathways is of vital importance in the transmission of information for cells in a network. The current literature assumes a single cell state is used to encode information, however, recent research suggests the optimal strategy utilizes a vector of cell states sampled at various time points. To elucidate the optimal sampling strategy for vector encoding, we take an information theoretic approach and determine the mutual information of the calcium signaling dynamics obtained from fibroblast cells perturbed with different concentrations of ATP. Specifically, we analyze the sampling strategies under the cases of fixed and non-fixed vector dimension as well as the efficiency of these strategies. Our results show that sampling with greater frequency is optimal in the case of non-fixed vector dimension but that, in general, a lower sampling frequency is best from both a fixed vector dimension and efficiency standpoint. Further, we find the use of a simple modified Ornstein-Uhlenbeck process as a model qualitatively captures many of our experimental results suggesting that sampling in biochemical networks is based on a few basic components.

  12. Ensemble Dynamics and Bred Vectors

    CERN Document Server

    Balci, Nusret; Restrepo, Juan M; Sell, George R

    2011-01-01

    We introduce the new concept of an EBV to assess the sensitivity of model outputs to changes in initial conditions for weather forecasting. The new algorithm, which we call the "Ensemble Bred Vector" or EBV, is based on collective dynamics in essential ways. By construction, the EBV algorithm produces one or more dominant vectors. We investigate the performance of EBV, comparing it to the BV algorithm as well as the finite-time Lyapunov Vectors. We give a theoretical justification to the observed fact that the vectors produced by BV, EBV, and the finite-time Lyapunov vectors are similar for small amplitudes. Numerical comparisons of BV and EBV for the 3-equation Lorenz model and for a forced, dissipative partial differential equation of Cahn-Hilliard type that arises in modeling the thermohaline circulation, demonstrate that the EBV yields a size-ordered description of the perturbation field, and is more robust than the BV in the higher nonlinear regime. The EBV yields insight into the fractal structure of th...

  13. Flavivirus RNAi suppression: decoding non-coding RNA.

    Science.gov (United States)

    Pijlman, Gorben P

    2014-08-01

    Flaviviruses are important human pathogens that are transmitted by invertebrate vectors, mostly mosquitoes and ticks. During replication in their vector, flaviviruses are subject to a potent innate immune response known as antiviral RNA interference (RNAi). This defense mechanism is associated with the production of small interfering (si)RNA that lead to degradation of viral RNA. To what extent flaviviruses would benefit from counteracting antiviral RNAi is subject of debate. Here, the experimental evidence to suggest the existence of flavivirus RNAi suppressors is discussed. I will highlight the putative role of non-coding, subgenomic flavivirus RNA in suppression of RNAi in insect and mammalian cells. Novel insights from ongoing research will reveal how arthropod-borne viruses modulate innate immunity including antiviral RNAi. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. Gauge Theories of Vector Particles

    Science.gov (United States)

    Glashow, S. L.; Gell-Mann, M.

    1961-04-24

    The possibility of generalizing the Yang-Mills trick is examined. Thus we seek theories of vector bosons invariant under continuous groups of coordinate-dependent linear transformations. All such theories may be expressed as superpositions of certain "simple" theories; we show that each "simple theory is associated with a simple Lie algebra. We may introduce mass terms for the vector bosons at the price of destroying the gauge-invariance for coordinate-dependent gauge functions. The theories corresponding to three particular simple Lie algebras - those which admit precisely two commuting quantum numbers - are examined in some detail as examples. One of them might play a role in the physics of the strong interactions if there is an underlying super-symmetry, transcending charge independence, that is badly broken. The intermediate vector boson theory of weak interactions is discussed also. The so-called "schizon" model cannot be made to conform to the requirements of partial gauge-invariance.

  15. 3D vector flow imaging

    DEFF Research Database (Denmark)

    Pihl, Michael Johannes

    The main purpose of this PhD project is to develop an ultrasonic method for 3D vector flow imaging. The motivation is to advance the field of velocity estimation in ultrasound, which plays an important role in the clinic. The velocity of blood has components in all three spatial dimensions, yet...... conventional methods can estimate only the axial component. Several approaches for 3D vector velocity estimation have been suggested, but none of these methods have so far produced convincing in vivo results nor have they been adopted by commercial manufacturers. The basis for this project is the Transverse...... on the TO fields are suggested. They can be used to optimize the TO method. In the third part, a TO method for 3D vector velocity estimation is proposed. It employs a 2D phased array transducer and decouples the velocity estimation into three velocity components, which are estimated simultaneously based on 5...

  16. 3-D Vector Flow Imaging

    DEFF Research Database (Denmark)

    Holbek, Simon

    studies and in vivo. Phantom measurements are compared with their corresponding reference value, whereas the in vivo measurement is validated against the current golden standard for non-invasive blood velocity estimates, based on magnetic resonance imaging (MRI). The study concludes, that a high precision......, if this significant reduction in the element count can still provide precise and robust 3-D vector flow estimates in a plane. The study concludes that the RC array is capable of estimating precise 3-D vector flow both in a plane and in a volume, despite the low channel count. However, some inherent new challenges......For the last decade, the field of ultrasonic vector flow imaging has gotten an increasingly attention, as the technique offers a variety of new applications for screening and diagnostics of cardiovascular pathologies. The main purpose of this PhD project was therefore to advance the field of 3-D...

  17. Skyrmions with vector mesons revisited

    CERN Document Server

    Oh, Yongseok

    2014-01-01

    In order to develop a model that can describe both a single baryon and multi-baryon systems on the same footing, we re-investigate the Skyrme model in a chiral Lagrangian derived from the hidden local symmetry (HLS) up to $O(p^4)$ including the homogeneous Wess-Zumino terms. We use the master formulas that connect the parameters of the HLS Lagrangian and a class of holographic QCD models, which provides a controllable way to determine the low-energy constants of the Lagrangian once the pion decay constant and the vector meson mass are given. Therefore, this model allows us to study the role of vector mesons in the skyrmion structure. We find that the $\\rho$ and $\\omega$ vector mesons have different roles in the skyrmion structure and that the $\\omega$ meson has an important role in the properties of the nucleon.

  18. Quantum contextuality for rational vectors

    CERN Document Server

    Cabello, Adan

    2010-01-01

    The Kochen-Specker theorem states that noncontextual hidden variable models are inconsistent with the quantum predictions for every yes-no question on a qutrit, corresponding to every projector in three dimensions. It has been suggested [D. A. Meyer, Phys. Rev. Lett. 83, 3751 (1999)] that the inconsistency would disappear when we are restricted to projectors on unit vectors with rational components; that noncontextual hidden variables could reproduce the quantum predictions for rational vectors. Here we show that a qutrit state with rational components violates an inequality valid for noncontextual hidden-variable models [A. A. Klyachko et al., Phys. Rev. Lett. 101, 020403 (2008)] using rational projectors. This shows that the inconsistency remains even when using only rational vectors.

  19. Vector bundles on toric varieties

    CERN Document Server

    Gharib, Saman

    2011-01-01

    Following Sam Payne's work, we study the existence problem of nontrivial vector bundles on toric varieties. The first result we prove is that every complete fan admits a nontrivial conewise linear multivalued function. Such functions could potentially be the Chern classes of toric vector bundles. Then we use the results of Corti\\~nas, Haesemeyer, Walker and Weibel to show that the (non-equivariant) Grothendieck group of the toric 3-fold studied by Payne is large, so the variety has a nontrivial vector bundle. Using the same computation, we show that every toric 3-fold X either has a nontrivial line bundle, or there is a finite surjective toric morphism from Y to X, such that Y has a large Grothendieck group.

  20. Quantum contextuality for rational vectors

    Energy Technology Data Exchange (ETDEWEB)

    Cabello, Adan, E-mail: adan@us.e [Departamento de Fisica Aplicada II, Universidad de Sevilla, E-41012 Sevilla (Spain); Larsson, Jan-Ake, E-mail: jan-ake.larsson@liu.s [Institutionen foer Systemteknik, Linkoepings Universitet, SE-581 83 Linkoeping (Sweden)

    2010-12-01

    The Kochen-Specker theorem states that noncontextual hidden variable models are inconsistent with the quantum predictions for every yes-no question on a qutrit, corresponding to every projector in three dimensions. It has been suggested [D.A. Meyer, Phys. Rev. Lett. 83 (1999) 3751] that the inconsistency would disappear when restricting to projectors on unit vectors with rational components; that noncontextual hidden variables could reproduce the quantum predictions for rational vectors. Here we show that a qutrit state with rational components violates an inequality valid for noncontextual hidden-variable models [A.A. Klyachko et al., Phys. Rev. Lett. 101 (2008) 020403] using rational projectors. This shows that the inconsistency remains even when using only rational vectors.

  1. Learning with Support Vector Machines

    CERN Document Server

    Campbell, Colin

    2010-01-01

    Support Vectors Machines have become a well established tool within machine learning. They work well in practice and have now been used across a wide range of applications from recognizing hand-written digits, to face identification, text categorisation, bioinformatics, and database marketing. In this book we give an introductory overview of this subject. We start with a simple Support Vector Machine for performing binary classification before considering multi-class classification and learning in the presence of noise. We show that this framework can be extended to many other scenarios such a

  2. Requirements for airborne vector gravimetry

    Science.gov (United States)

    Schwarz, K. P.; Colombo, O.; Hein, G.; Knickmeyer, E. T.

    1992-01-01

    The objective of airborne vector gravimetry is the determination of the full gravity disturbance vector along the aircraft trajectory. The paper briefly outlines the concept of this method using a combination of inertial and GPS-satellite data. The accuracy requirements for users in geodesy and solid earth geophysics, oceanography and exploration geophysics are then specified. Using these requirements, accuracy specifications for the GPS subsystem and the INS subsystem are developed. The integration of the subsystems and the problems connected with it are briefly discussed and operational methods are indicated that might reduce some of the stringent accuracy requirements.

  3. Vector Theory in Relativistic Thermodynamics

    Institute of Scientific and Technical Information of China (English)

    刘泽文

    1994-01-01

    It is pointed out that five defects occur in Planck-Einstein’s relativistic thermodynamics (P-E theory). A vector theory in relativistic thermodynamics (VTRT) is established. Defining the internal energy as a 4-vector, and supposing the entropy and the number of. particles to be invariants we have derived the transformations of all quantities, and subsequently got the Lagrangian and 4-D forms of thermodynamic laws. In order to test the new theory, several exact solutions with classical limits are given. The VTRT is free from the defects of the P-E theory.

  4. High-level expressing YAC vector for transgenic animal bioreactors.

    Science.gov (United States)

    Fujiwara, Y; Miwa, M; Takahashi, R; Kodaira, K; Hirabayashi, M; Suzuki, T; Ueda, M

    1999-04-01

    The position effect is one major problem in the production of transgenic animals as mammary gland bioreactors. In the present study, we introduced the human growth hormone (hGH) gene into 210-kb human alpha-lactalbumin position-independent YAC vectors using homologous recombination and produced transgenic rats via microinjection of YAC DNA into rat embryos. The efficiency of producing transgenic rats with the YAC vector DNA was the same as that using plasmid constructs. All analyzed transgenic rats had one copy of the transgene and produced milk containing a high level of hGH (0.25-8.9 mg/ml). In transgenic rats with the YAC vector in which the human alpha-lactalbumin gene was replaced with the hGH gene, tissue specificity of hGH mRNA was the same as that of the endogenous rat alpha-lactalbumin gene. Thus, the 210-kb human alpha-lactalbumin YAC is a useful vector for high-level expression of foreign genes in the milk of transgenic animals.

  5. Regulation of U6 Promoter Activity by Transcriptional Interference in Viral Vector-Based RNAi

    Institute of Scientific and Technical Information of China (English)

    Linghu Nie; Meghna Das Thakur; Yumei Wang; Qin Su; Yongliang Zhao; Yunfeng Feng

    2010-01-01

    The direct negative impact of the transcriptional activity of one component on the second one in c/s is referred to as transcriptional interference (TI).U6 is a type Ⅲ RNA polymerase Ⅲ promoter commonly used for driving small hairpin RNA (shRNA) expression in vector-based RNAi.In the design and construction of viral vectors,multiple transcription units may be arranged in close proximity in a space-limited vector.Determining if U6 promoter activity can be affected by TI is critical for the expression of target shRNA in gene therapy or loss-of-function studies.In this research,we designed and implemented a modified retroviral system where shRNA and exogenous gene expressions were driven by two independent transcriptional units.We arranged U6 promoter driving.shRNA expression and UbiC promoter in two promoter arrangements.In primary macrophages,we found U6 promoter activity was inhibited by UbiC promoter when in the divergent arrangement but not in tandem.In contrast,PKG promoter had no such negative impact.Instead of enhancing U6 promoter activity,CMV enhancer had significant negative impact on U6 promoter activity in the presence of UbiC promoter.Our results indicate that U6 promoter activity can be affected by TI in a proximal promoter-specific and arrangement-dependent manner.

  6. Construct Hairpin RNA to Fight Against Rice Dwarf Virus

    Institute of Scientific and Technical Information of China (English)

    MAZhong-Liang; YANGHuai-Yi; WANGRong; TIENPo

    2004-01-01

    Hairpin RNA (hpRNA) can induce post-transcriptional gene silencing, and was constructed with128-754 bp of segment 8 of rice dwarf virus then placed under the control of the CaMV35S promoter andused to transform rice cultivar "Zhonghua 11" via Agrobacterium tumefaciens. A total of 12 independentlines containing hpRNA were obtained as demonstrated by Southern blotting analysis. Challenge inocula-tion with rice dwarf virus (RDV) viruliferous leafhoppers (Nephotettix cincticeps) showed that T1 plantscontaining the hpRNA transgene displayed high resistance or delayed and attenuated viral symptoms. Incontrast, transgenic lines expressing sense RNA showed severe symptoms similar to control plants trans-formed with the vector alone. These results suggest that hpRNA confers high resistance to RDV intransgenic rice.

  7. Self-replicating alphavirus RNA vaccines.

    Science.gov (United States)

    Ljungberg, Karl; Liljeström, Peter

    2015-02-01

    Recombinant nucleic acids are considered as promising next-generation vaccines. These vaccines express the native antigen upon delivery into tissue, thus mimicking live attenuated vaccines without having the risk of reversion to pathogenicity. They also stimulate the innate immune system, thus potentiating responses. Nucleic acid vaccines are easy to produce at reasonable cost and are stable. During the past years, focus has been on the use of plasmid DNA for vaccination. Now mRNA and replicon vaccines have come into focus as promising technology platforms for vaccine development. This review discusses self-replicating RNA vaccines developed from alphavirus expression vectors. These replicon vaccines can be delivered as RNA, DNA or as recombinant virus particles. All three platforms have been pre-clinically evaluated as vaccines against a number of infectious diseases and cancer. Results have been very encouraging and propelled the first human clinical trials, the results of which have been promising.

  8. Production of Recombinant Vector Containing the Coding Sequence of Human Hepcidin

    Directory of Open Access Journals (Sweden)

    Keyhanvar, N.

    2013-01-01

    Full Text Available Background and objective: Hepcidin is a cystein-rich antimicrobial peptide,which is secreted by the liver. It fights against wide spectrum of bacteria, virusesand fungi and it is a major regulator of iron homeostasis. Today, scientists havemade many efforts on the production of hepcidin. Baculovirus expression systemis one of the best eukaryotic expression systems for production of recombinanthepcidin and production of the recombinant vector is one of the most importantsteps in this expression system.Material & Methods: First, the total RNA was separated from HepG2 cell lineas a source of hepcidin expression. Then, after synthesis of total cDNA, humanhepcidin sequence was amplified, using specific primers by PCR method. Next,hepcidin sequence was cloned into pTZ57R/T vector. After digestion ofrecombinant vector using ECoRI and BamHI restriction enzymes, recombinantpFastBac HT B vector containing human hepcidin cDNA was produced.Results: Coding sequence of human hepcidin is correctly cloned into pTZ57R/Tvector and sub cloning into pFastBac HT B vector is performed successfully. Thepresence of a clear band near 274 bp resulted from PCR amplification andrestriction enzyme are the confirmation of the cloning of human hepcidin.Conclusion: According to our knowledge, the present study is the first work thatfocuses on recombinant vector containing coding sequence of human prohepcidin.This recombinant vector can be used for human hepcidin production.Keywords: Vector; Hepcidin; Iron

  9. Newcastle Disease Virus as a Vaccine Vector for Development of Human and Veterinary Vaccines.

    Science.gov (United States)

    Kim, Shin-Hee; Samal, Siba K

    2016-07-04

    Viral vaccine vectors have shown to be effective in inducing a robust immune response against the vaccine antigen. Newcastle disease virus (NDV), an avian paramyxovirus, is a promising vaccine vector against human and veterinary pathogens. Avirulent NDV strains LaSota and B1 have long track records of safety and efficacy. Therefore, use of these strains as vaccine vectors is highly safe in avian and non-avian species. NDV replicates efficiently in the respiratory track of the host and induces strong local and systemic immune responses against the foreign antigen. As a vaccine vector, NDV can accommodate foreign sequences with a good degree of stability and as a RNA virus, there is limited possibility for recombination with host cell DNA. Using NDV as a vaccine vector in humans offers several advantages over other viral vaccine vectors. NDV is safe in humans due to host range restriction and there is no pre-existing antibody to NDV in the human population. NDV is antigenically distinct from common human pathogens. NDV replicates to high titer in a cell line acceptable for human vaccine development. Therefore, NDV is an attractive vaccine vector for human pathogens for which vaccines are currently not available. NDV is also an attractive vaccine vector for animal pathogens.

  10. Role of microRNAs in arbovirus/vector interactions.

    Science.gov (United States)

    Asgari, Sassan

    2014-09-23

    The role of microRNAs (miRNAs) as small non-coding RNAs in regulation of gene expression has been recognized. They appear to be involved in regulation of a wide range of cellular pathways that affect several biological processes such as development, the immune system, survival, metabolism and host-pathogen interactions. Arthropod-borne viruses impose great economic and health risks around the world. Recent advances in miRNA biology have shed some light on the role of these small RNAs in vector-virus interactions. In this review, I will reflect on our current knowledge on the role of miRNAs in arbovirus-vector interactions and the potential avenues for their utilization in limiting virus replication and/or transmission.

  11. Foamy virus biology and its application for vector development.

    Science.gov (United States)

    Lindemann, Dirk; Rethwilm, Axel

    2011-05-01

    Spuma- or foamy viruses (FV), endemic in most non-human primates, cats, cattle and horses, comprise a special type of retrovirus that has developed a replication strategy combining features of both retroviruses and hepadnaviruses. Unique features of FVs include an apparent apathogenicity in natural hosts as well as zoonotically infected humans, a reverse transcription of the packaged viral RNA genome late during viral replication resulting in an infectious DNA genome in released FV particles and a special particle release strategy depending capsid and glycoprotein coexpression and specific interaction between both components. In addition, particular features with respect to the integration profile into the host genomic DNA discriminate FV from orthoretroviruses. It appears that some inherent properties of FV vectors set them favorably apart from orthoretroviral vectors and ask for additional basic research on the viruses as well as on the application in Gene Therapy. This review will summarize the current knowledge of FV biology and the development as a gene transfer system.

  12. Vector-meson dominance revisited

    Directory of Open Access Journals (Sweden)

    Terschlüsen Carla

    2012-12-01

    Full Text Available The interaction of mesons with electromagnetism is often well described by the concept of vector-meson dominance (VMD. However, there are also examples where VMD fails. A simple chiral Lagrangian for pions, rho and omega mesons is presented which can account for the respective agreement and disagreement between VMD and phenomenology in the sector of light mesons.

  13. Parallel Sparse Matrix - Vector Product

    DEFF Research Database (Denmark)

    Alexandersen, Joe; Lazarov, Boyan Stefanov; Dammann, Bernd

    This technical report contains a case study of a sparse matrix-vector product routine, implemented for parallel execution on a compute cluster with both pure MPI and hybrid MPI-OpenMP solutions. C++ classes for sparse data types were developed and the report shows how these class can be used...

  14. The consequences of poor vectorization

    CERN Document Server

    CERN. Geneva

    2016-01-01

    This talk briefly discusses the vectorization problem and how it impacts scientific and engineering systems. A simple cost model of designing such system in context of different phases of software lifetime is considered. Finally a concept for scalable solution is presented.

  15. Sparse Matrix Vector Processing Formats

    NARCIS (Netherlands)

    Stathis, P.T.

    2004-01-01

    In this dissertation we have identified vector processing shortcomings related to the efficient storing and processing of sparse matrices. To alleviate existent problems we propose two storage formats denoted as Block Based Compression Storage (BBCS) format and Hierarchical Sparse Matrix (HiSM) stor

  16. Bifurcations of optimal vector fields

    NARCIS (Netherlands)

    Kiseleva, T.; Wagener, F.

    2015-01-01

    We study the structure of the solution set of a class of infinite-horizon dynamic programming problems with one-dimensional state spaces, as well as their bifurcations, as problem parameters are varied. The solutions are represented as the integral curves of a multivalued optimal vector field on sta

  17. Portfolio Analysis for Vector Calculus

    Science.gov (United States)

    Kaplan, Samuel R.

    2015-01-01

    Classic stock portfolio analysis provides an applied context for Lagrange multipliers that undergraduate students appreciate. Although modern methods of portfolio analysis are beyond the scope of vector calculus, classic methods reinforce the utility of this material. This paper discusses how to introduce classic stock portfolio analysis in a…

  18. Phlebotomine Vectors of Human Disease.

    Science.gov (United States)

    1983-12-30

    different. We refrain from naming this specimen until more material becomes available. 12. Lutzomyia olmeca bicolor Fairchild and Theodor 1971...Castillo (1958) and Arzube (1960). Lutzomyia olmeca bicolor is the suspected vector of Leishmania mexicana aristedesi among rodents and marsupials in

  19. Phase transitions in Vector Quantization

    NARCIS (Netherlands)

    Witoelar, Aree; Ghosh, Anarta; Biehl, Michael; Verleysen, Michel

    2008-01-01

    We study Winner-Takes-All and rank based Vector Quantization along the lines of the statistical physics of off-line learning. Typical behavior of the system is obtained within a model where high-dimensional training data are drawn from a mixture of Gaussians. The analysis becomes exact in the simpli

  20. Portfolio Analysis for Vector Calculus

    Science.gov (United States)

    Kaplan, Samuel R.

    2015-01-01

    Classic stock portfolio analysis provides an applied context for Lagrange multipliers that undergraduate students appreciate. Although modern methods of portfolio analysis are beyond the scope of vector calculus, classic methods reinforce the utility of this material. This paper discusses how to introduce classic stock portfolio analysis in a…

  1. SCALAR AND VECTOR IN COMPULATION

    Directory of Open Access Journals (Sweden)

    Valery F. Ochkov

    2013-01-01

    Full Text Available The article deals with two fundamental data types – scalar and vector (array, without the ability of working with them one cannot solve using computer school or university tasks in mathematics, physics, chemistry and other technical training courses. Some fundamentals of teaching computer science at school and university are covered as well. 

  2. Vector-valued fuzzy multifunctions

    Directory of Open Access Journals (Sweden)

    Ismat Beg

    2001-01-01

    Full Text Available Some of the properties of vector-valued fuzzy multifunctions are studied. The notion of sum fuzzy multifunction, convex hull fuzzy multifunction, close convex hull fuzzy multifunction, and upper demicontinuous are given, and some of the properties of these fuzzy multifunctions are investigated.

  3. Scalar Calibration of Vector Magnetometers

    DEFF Research Database (Denmark)

    Merayo, José M.G.; Brauer, Peter; Primdahl, Fritz;

    2000-01-01

    The calibration parameters of a vector magnetometer are estimated only by the use of a scalar reference magnetometer. The method presented in this paper differs from those previously reported in its linearized parametrization. This allows the determination of three offsets or signals in the absence...

  4. Vector ecology of equine piroplasmosis

    Science.gov (United States)

    Equine piroplasmosis (EP) is a disease of equidae including horses, donkeys, mules and zebras caused by either of two protozoan parasites, Theileria equi or Babesia caballi. These parasites are biologically transmitted between hosts via tick-vectors and although they have inherent differences, they ...

  5. Parallel Sparse Matrix - Vector Product

    DEFF Research Database (Denmark)

    Alexandersen, Joe; Lazarov, Boyan Stefanov; Dammann, Bernd

    This technical report contains a case study of a sparse matrix-vector product routine, implemented for parallel execution on a compute cluster with both pure MPI and hybrid MPI-OpenMP solutions. C++ classes for sparse data types were developed and the report shows how these class can be used...

  6. Vector Bundles over Elliptic Fibrations

    CERN Document Server

    Friedman, R; Witten, Edward; Friedman, Robert; Morgan, John W.; Witten, Edward

    1997-01-01

    This paper gives various methods for constructing vector bundles over elliptic curves and more generally over families of elliptic curves. We construct universal families over generalized elliptic curves via spectral cover methods and also by extensions, and then give a relative version of the construction in families. We give various examples and make Chern class computations.

  7. Large N Expansion. Vector Models

    CERN Document Server

    Nissimov, E; Nissimov, Emil; Pacheva, Svetlana

    2006-01-01

    Preliminary version of a contribution to the "Quantum Field Theory. Non-Perturbative QFT" topical area of "Modern Encyclopedia of Mathematical Physics" (SELECTA), eds. Aref'eva I, and Sternheimer D, Springer (2007). Consists of two parts - "main article" (Large N Expansion. Vector Models) and a "brief article" (BPHZL Renormalization).

  8. Inhibiting avian influenza virus shedding using a novel RNAi antiviral vector technology: proof of concept in an avian cell model.

    Science.gov (United States)

    Linke, Lyndsey M; Wilusz, Jeffrey; Pabilonia, Kristy L; Fruehauf, Johannes; Magnuson, Roberta; Olea-Popelka, Francisco; Triantis, Joni; Landolt, Gabriele; Salman, Mo

    2016-03-01

    Influenza A viruses pose significant health and economic threats to humans and animals. Outbreaks of avian influenza virus (AIV) are a liability to the poultry industry and increase the risk for transmission to humans. There are limitations to using the AIV vaccine in poultry, creating barriers to controlling outbreaks and a need for alternative effective control measures. Application of RNA interference (RNAi) techniques hold potential; however, the delivery of RNAi-mediating agents is a well-known obstacle to harnessing its clinical application. We introduce a novel antiviral approach using bacterial vectors that target avian mucosal epithelial cells and deliver (small interfering RNA) siRNAs against two AIV genes, nucleoprotein (NP) and polymerase acidic protein (PA). Using a red fluorescent reporter, we first demonstrated vector delivery and intracellular expression in avian epithelial cells. Subsequently, we demonstrated significant reductions in AIV shedding when applying these anti-AIV vectors prophylactically. These antiviral vectors provided up to a 10,000-fold reduction in viral titers shed, demonstrating in vitro proof-of-concept for using these novel anti-AIV vectors to inhibit AIV shedding. Our results indicate this siRNA vector technology could represent a scalable and clinically applicable antiviral technology for avian and human influenza and a prototype for RNAi-based vectors against other viruses.

  9. Generation of a human induced pluripotent stem cell line CERAi001-A-6 using episomal vectors

    Directory of Open Access Journals (Sweden)

    Raymond C.B. Wong

    2017-07-01

    Full Text Available We report the generation of the hiPSC line CERAi001-A-6 from primary human dermal fibroblasts. Reprogramming was performed using episomal vector delivery of OCT4, SOX2, KLF4, L-MYC, LIN28 and shRNA for p53.

  10. Non-essential viral proteins of orbiviruses are essential for vector-borne spread by midges

    Science.gov (United States)

    Members of the Reoviridae family are non-enveloped multi-layered viruses with a double stranded RNA genome consisting of 9-12 genome segments. The Orbivirus genus contains vector borne virus species with 10 genome segments such as bluetongue virus (BTV) with about 30 serotypes, and African horse sic...

  11. Combinatorics of RNA-RNA interaction

    DEFF Research Database (Denmark)

    Li, Thomas J X; Reidys, Christian

    2012-01-01

    RNA-RNA binding is an important phenomenon observed for many classes of non-coding RNAs and plays a crucial role in a number of regulatory processes. Recently several MFE folding algorithms for predicting the joint structure of two interacting RNA molecules have been proposed. Here joint structure...... means that in a diagram representation the intramolecular bonds of each partner are pseudoknot-free, that the intermolecular binding pairs are noncrossing, and that there is no so-called "zigzag" configuration. This paper presents the combinatorics of RNA interaction structures including...

  12. Predicting RNA-Protein Interactions Using Only Sequence Information

    Directory of Open Access Journals (Sweden)

    Muppirala Usha K

    2011-12-01

    Full Text Available Abstract Background RNA-protein interactions (RPIs play important roles in a wide variety of cellular processes, ranging from transcriptional and post-transcriptional regulation of gene expression to host defense against pathogens. High throughput experiments to identify RNA-protein interactions are beginning to provide valuable information about the complexity of RNA-protein interaction networks, but are expensive and time consuming. Hence, there is a need for reliable computational methods for predicting RNA-protein interactions. Results We propose RPISeq, a family of classifiers for predicting RNA-protein interactions using only sequence information. Given the sequences of an RNA and a protein as input, RPIseq predicts whether or not the RNA-protein pair interact. The RNA sequence is encoded as a normalized vector of its ribonucleotide 4-mer composition, and the protein sequence is encoded as a normalized vector of its 3-mer composition, based on a 7-letter reduced alphabet representation. Two variants of RPISeq are presented: RPISeq-SVM, which uses a Support Vector Machine (SVM classifier and RPISeq-RF, which uses a Random Forest classifier. On two non-redundant benchmark datasets extracted from the Protein-RNA Interface Database (PRIDB, RPISeq achieved an AUC (Area Under the Receiver Operating Characteristic (ROC curve of 0.96 and 0.92. On a third dataset containing only mRNA-protein interactions, the performance of RPISeq was competitive with that of a published method that requires information regarding many different features (e.g., mRNA half-life, GO annotations of the putative RNA and protein partners. In addition, RPISeq classifiers trained using the PRIDB data correctly predicted the majority (57-99% of non-coding RNA-protein interactions in NPInter-derived networks from E. coli, S. cerevisiae, D. melanogaster, M. musculus, and H. sapiens. Conclusions Our experiments with RPISeq demonstrate that RNA-protein interactions can be

  13. Vector variational inequalities and their relations with vector optimization

    Directory of Open Access Journals (Sweden)

    Surjeet Kaur Suneja

    2014-01-01

    Full Text Available In this paper, K- quasiconvex, K- pseudoconvex and other related functions have been introduced in terms of their Clarke subdifferentials, where is an arbitrary closed convex, pointed cone with nonempty interior. The (strict, weakly -pseudomonotonicity, (strict K- naturally quasimonotonicity and K- quasimonotonicity of Clarke subdifferential maps have also been defined. Further, we introduce Minty weak (MVVIP and Stampacchia weak (SVVIP vector variational inequalities over arbitrary cones. Under regularity assumption, we have proved that a weak minimum solution of vector optimization problem (VOP is a solution of (SVVIP and under the condition of K- pseudoconvexity we have obtained the converse for MVVIP (SVVIP. In the end we study the interrelations between these with the help of strict K-naturally quasimonotonicity of Clarke subdifferential map.

  14. Vector-Boson Fusion and Vector-Boson Scattering

    CERN Document Server

    Rauch, Michael

    2016-01-01

    Vector-boson fusion and vector-boson scattering are an important class of processes for the Large Hadron Collider at CERN. It is characterized by two high-energetic jets in the forward regions of the detector and reduced jet activity in the central region. The higher center-of-mass energy during the current and subsequent runs strongly boosts the sensitivity in these processes and allows to test the predictions of the Standard Model to a high precision. In this review, we first present the main phenomenological features of vector-boson fusion and scattering processes. Then we discuss the effects of higher-order corrections, which are available at NLO QCD for all processes and up to N3LO QCD and NLO electro-weak for VBF-H production. An additional refinement is the addition of parton-shower effects, where recently a lot of progress has been made. The appearance of triple and quartic gauge vertices in the production processes enables us to probe anomalous gauge couplings. We introduce and compare the different ...

  15. Determinants of effective lentivirus-driven microRNA expression in vivo.

    Science.gov (United States)

    Mishima, Takuya; Sadovsky, Elena; Gegick, Margaret E; Sadovsky, Yoel

    2016-09-15

    Manipulation of microRNA (miRNA) levels, including overexpression of mature species, has become an important biological tool, even motivating miRNA-based therapeutics. To assess key determinants of miRNA overexpression in a mammalian system in vivo, we sought to bypass the laborious generation of a transgenic animal by exploiting placental trophoblast-specific gene manipulation using lentiviral vectors, which has been instrumental in elucidating trophoblast biology. We examined the impact of several key components of miRNA stem loops and their flanking sequences on the efficiency of mature miRNA expression in vivo. By combining established and novel approaches for miRNA expression, we engineered lentivirus-driven miRNA expression plasmids, which we tested in the mouse placenta. We found that reverse sense inserts minimized single-strand splicing and degradation, and that maintaining longer, poly-A-containing arms flanking the miRNA stem-loop markedly enhanced transgenic miRNA expression. Additionally, we accomplished overexpression of diverse mammalian, drosophila, or C. elegans miRNAs, either based on native context or using a "cassette" replacement of the mature miRNA sequence. Together, we have identified primary miRNA sequences that are paramount for effective expression of mature miRNAs, and validated their role in mice. Principles established by our findings may guide the design of efficient miRNA vectors for in vivo use.

  16. Selection of functional tRNA primers and primer binding site sequences from a retroviral combinatorial library: identification of new functional tRNA primers in murine leukemia virus replication

    DEFF Research Database (Denmark)

    Lund, Anders Henrik; Duch, M; Pedersen, F S

    2000-01-01

    . While most of the selected primer binding sites are complementary to the 3'-end of tRNA((Pro)), we also retrieved PBS sequences matching four other tRNA molecules and demonstrate that Akv murine leukemia virus vectors may efficiently replicate using tRNA(Arg(CCU)), tRNA(Phe(GAA))and a hitherto unknown......Retroviral reverse transcription is initiated from a cellular tRNA molecule and all known exogenous isolates of murine leukemia virus utilise a tRNA(Pro)molecule. While several studies suggest flexibility in murine leukemia virus primer utilisation, studies on human immunodeficiency virus and avian...... retro-viruses have revealed evidence of molecular adapt-ation towards the specific tRNA isoacceptor used as replication primer. In this study, murine leukemia virus tRNA utilisation is investigated by in vivo screening of a retroviral vector combinatorial library with randomised primer binding sites...

  17. Symbolic Vector Analysis in Plasma Physics

    Energy Technology Data Exchange (ETDEWEB)

    Qin, H.; Tang, W.M.; Rewoldt, G.

    1997-10-09

    Many problems in plasma physics involve substantial amounts of analytical vector calculation. The complexity usually originates from both the vector operations themselves and the choice of underlying coordinate system. A computer algebra package for symbolic vector analysis in general coordinate systems, General Vector Analysis (GVA), is developed using Mathematica. The modern viewpoint for 3D vector calculus, differential forms on 3-manifolds, is adopted to unify and systematize the vector calculus operations in general coordinate systems. This package will benefit physicists and applied mathematicians in their research where complicated vector analysis is required. It will not only save a huge amount of human brain-power and dramatically improve accuracy, but this package will also be an intelligent tool to assist researchers in finding the right approaches to their problems. Several applications of this symbolic vector analysis package to plasma physics are also given.

  18. Symbolic Vector Analysis in Plasma Physics

    Energy Technology Data Exchange (ETDEWEB)

    Qin, H.; Rewoldt, G.; Tang, W.M.

    1997-10-01

    Many problems in plasma physics involve substantial amounts of analytical vector calculation. The complexity usually originates from both the vector operations themselves and the choice of underlying coordinate system. A computer algebra package for symbolic vector analysis in general coordinate systems, GeneralVectorAnalysis (GVA), is developed using Mathematica. The modern viewpoint for 3D vector calculus, differential forms on 3-manifolds, is adopted to unify and systematize the vector calculus operations in general coordinate systems. This package will benefit physicists and applied mathematicians in their research where complicated vector analysis is required. It will not only save a huge amount of human brain-power and dramatically improve accuracy, but this package will also be an intelligent tool to assist researchers in finding the right approaches to their problems. Several applications of this symbolic vector analysis package to plasma physics are also given.

  19. On third order integrable vector Hamiltonian equations

    Science.gov (United States)

    Meshkov, A. G.; Sokolov, V. V.

    2017-03-01

    A complete list of third order vector Hamiltonian equations with the Hamiltonian operator Dx having an infinite series of higher conservation laws is presented. A new vector integrable equation on the sphere is found.

  20. SYSTEM OF GENERALIZED VECTOR VARIATIONAL INEQUALITIES

    Institute of Scientific and Technical Information of China (English)

    Fang Yaping; Huang Nanjing

    2005-01-01

    In this paper, the authors introduce and study system of generalized vector variational inequalities. Under suitable conditions, the existence of solutions for system of generalized vector variational inequalities is presented by Kakutani-Fan-Glicksberg fixed point theorem.

  1. 双基因shRNA干扰乙酰肝素酶在卵巢癌细胞中表达的实验研究%Inhibition of heparanase gene expression by double shRNA expressing vector in ovarian carcinoma cells

    Institute of Scientific and Technical Information of China (English)

    刘玉; 辛晓燕; 毛敬; 张潍

    2006-01-01

    目的:采用编码2条短发卡式RNA(shRNA)的抗乙酰肝素酶(heparanase,Hpa)特异性载体干扰卵巢癌细胞中Hpa的表达,观察其对肿瘤生长转移的抑制作用.方法:以脂质体介导的方法将自行设计和构建的抗Hpa短发卡式RNA(Hpa-shRNA)基因真核表达载体稳定转染人卵巢癌细胞SKOV3;流式细胞仪鉴定转染效率,免疫组化和实时定量RT-PCR检测转染前后卵巢癌细胞中Hpa蛋白和mRNA表达,Boyden小室观测细胞增殖和侵袭能力的变化,透射电镜观察卵巢癌细胞超微结构改变.结果:Hpa mRNA表达在SKOVa-Hpa(转染Hpa)明显升高(P<0.01),SKOV3-Hpa shRNA(转染Hpash RNA)显著降低(P<0.01),SKOV3 DZ-shRNA(转染非特异性sh RNA片段)和SKOV3无显著性差异(P>0.05).电镜下,SKOV3-Hpa组Hpa蛋白表达最为明显,SKOV3-Hpa shRNA Hpa蛋白则最低,各组间比较差别有显著性意义(P<0.01).SKOV3-Hpa细胞器发达,细胞表面绒毛丰富,细胞间连接稀少.SKOV3 Hpa-shRNA以变形为主,细胞表面绒毛少,细胞器不发达,部分见线粒体皱缩,肿胀和空泡样改变.SKOV3-Hpa、SKOV3-DZ-shRNA和SKOV3-Hpa-shRNA 3种细胞穿过人工基底膜的细胞数分别为82.3±9.16,36.1±8.73和18.6±10.5,各组间比较有显著性差异(P<0.01).结论:双基因Hpa特异性shRNA可显著抑制卵巢癌细胞Hpa表达,降低细胞侵袭能力.

  2. The Vienna RNA Websuite

    Science.gov (United States)

    Gruber, Andreas R.; Lorenz, Ronny; Bernhart, Stephan H.; Neuböck, Richard; Hofacker, Ivo L.

    2008-01-01

    The Vienna RNA Websuite is a comprehensive collection of tools for folding, design and analysis of RNA sequences. It provides a web interface to the most commonly used programs of the Vienna RNA package. Among them, we find folding of single and aligned sequences, prediction of RNA–RNA interactions, and design of sequences with a given structure. Additionally, we provide analysis of folding landscapes using the barriers program and structural RNA alignments using LocARNA. The web server together with software packages for download is freely accessible at http://rna.tbi.univie.ac.at/. PMID:18424795

  3. NEVILLE-TYPE VECTOR VALUED RATIONAL INTERPOLANTS

    Institute of Scientific and Technical Information of China (English)

    陈之兵; 顾传青; 徐晨

    2004-01-01

    A new kind of vector valued rational interpolants is established by means of Samelson inverse, with scalar numerator and vector valued denominator. It is essen tially different from that of Graves-Morris(1983), where the interpolants are constructed by Thiele-type continued fractions with vector valued numerator and scalar denominator. The new approach is more suitable to calculate the value of a vector valued function for a given point. And an error formula is also given and proven.

  4. Vectors and translations in mathematics and physics

    OpenAIRE

    Dorier, Jean-Luc

    2016-01-01

    In mathematics, students learn about vectors and translation, in physics they model forces, speed, acceleration, etc. with vectors and study movements of translation. Do they make the connection between these concepts introduced in different disciplines or do they put things in separate boxes? In this paper we will start with some partial considerations on the history of vectors and we will give some references. Then we will show some examples of naïve illustrations of vectors from physics in...

  5. Diffractive Leptoproduction of Vector Mesons in QCD

    OpenAIRE

    Brodsky, Stanley J.; Frankfurt, L.; Gunion, J. F.; Mueller, A.H.; Strikman, M.

    1994-01-01

    We demonstrate that the distinctive features of the forward differential cross section of diffractive leptoproduction of a vector meson can be legitimately calculated in perturbative QCD in terms of the light-cone $q \\bar q$ wave function of the vector meson and the gluon distribution of the target. In particular, we calculate the $Q^2$ and nuclear dependence of the diffractive leptoproduction of vector mesons and estimate the cross section. The production of longitudinally polarized vector m...

  6. Medium Modification of Vector Mesons

    Energy Technology Data Exchange (ETDEWEB)

    Chaden Djalali, Michael Paolone, Dennis Weygand, Michael H. Wood, Rakhsha Nasseripour

    2011-03-01

    The theory of the strong interaction, Quantum Chromodynamics (QCD), has been remarkably successful in describing high-energy and short-distance-scale experiments involving quarks and gluons. However, applying QCD to low energy and large-distance scale experiments has been a major challenge. Various QCD-inspired models predict a partial restoration of chiral symmetry in nuclear matter with modifications of the properties of hadrons from their free-space values. Measurable changes such as a shift in mass and/or a change of width are predicted at normal nuclear density. Photoproduction of vector mesons off nuclei have been performed at different laboratories. The properties of the ρ, ω and φ mesons are investigated either directly by measuring their mass spectra or indirectly through transparency ratios. The latest results regarding medium modifications of the vector mesons in the nuclear medium will be discussed.

  7. Lentiviral vectors in cancer immunotherapy.

    Science.gov (United States)

    Oldham, Robyn Aa; Berinstein, Elliot M; Medin, Jeffrey A

    2015-01-01

    Basic science advances in cancer immunotherapy have resulted in various treatments that have recently shown success in the clinic. Many of these therapies require the insertion of genes into cells to directly kill them or to redirect the host's cells to induce potent immune responses. Other analogous therapies work by modifying effector cells for improved targeting and enhanced killing of tumor cells. Initial studies done using γ-retroviruses were promising, but safety concerns centered on the potential for insertional mutagenesis have highlighted the desire to develop other options for gene delivery. Lentiviral vectors (LVs) have been identified as potentially more effective and safer alternative delivery vehicles. LVs are now in use in clinical trials for many different types of inherited and acquired disorders, including cancer. This review will discuss current knowledge of LVs and the applications of this viral vector-based delivery vehicle to cancer immunotherapy.

  8. Clinical applications of power vectors.

    Science.gov (United States)

    Miller, Joseph M

    2009-06-01

    The study of infant vision is closely coupled to the study of the refraction, change in refraction over time, and the effect of spectacle correction on visual development. Frequently, reports are limited to descriptions of spherical equivalent or cylinder power without regard to axis, as data are frequently collected in the clinical format of sphere, cylinder, and axis (S, C, A). Conversion from clinical notation to a power vector representation of refraction allows unambiguous description of how refractions change over time and differ between repeated measurements. This article presents a series of examples of Microsoft Excel spreadsheet formulas that make the conversion from clinical notation to power vector format, and provides examples of useful applications of these methods.

  9. Gene targeting with retroviral vectors

    Energy Technology Data Exchange (ETDEWEB)

    Ellis, J.; Bernstein, A. (Toronto Univ., ON (Canada))

    1989-04-01

    The authors have designed and constructed integration-defective retroviral vectors to explore their potential for gene targeting in mammalian cells. Two nonoverlapping deletion mutants of the bacterial neomycin resistance (neo) gene were used to detect homologous recombination events between viral and chromosomal sequences. Stable neo gene correction events were selected at a frequency of approximately 1 G418/sup r/ cell per 3 x 10/sup 6/ infected cells. Analysis of the functional neo gene in independent targeted cell clones indicated that unintegrated retroviral linear DNA recombined with the target by gene conversion for variable distances into regions of nonhomology. In addition, transient neo gene correction events which were associated with the complete loss of the chromosomal target sequences were observed. These results demonstrated that retroviral vectors can recombine with homologous chromosomal sequences in rodent and human cells.

  10. ELVIS - ELectromagnetic Vector Information Sensor

    CERN Document Server

    Bergman, J E S; Thidé, B; Ananthakrishnan, S; Wahlund, J E; Karlsson, R L; Puccio, W; Carozzi, T D; Kale, P

    2005-01-01

    The ELVIS instrument was recently proposed by the authors for the Indian Chandrayaan-1 mission to the Moon and is presently under consideration by the Indian Space Research Organisation (ISRO). The scientific objective of ELVIS is to explore the electromagnetic environment of the moon. ELVIS samples the full three-dimensional (3D) electric field vector, E(x,t), up to 18 MHz, with selective Nyqvist frequency bandwidths down to 5 kHz, and one component of the magnetic field vector, B(x,t), from a few Hz up to 100 kHz.As a transient detector, ELVIS is capable of detecting pulses with a minimum pulse width of 5 ns. The instrument comprises three orthogonal electric dipole antennas, one magnetic search coil antenna and a four-channel digital sampling system, utilising flexible digital down conversion and filtering together with state-of-the-art onboard digital signal processing.

  11. Vector monitoring at Belgian outbreak sites during the bluetongue epidemic of 2006.

    Science.gov (United States)

    De Deken, G; Madder, M; Deblauwe, I; De Clercq, K; Fassotte, C; Losson, B; Haubruge, E; De Deken, R

    2008-10-15

    In response to the first bluetongue outbreak in Belgium a monitoring programme was started at the end of August 2006 to identify possible vectors transmitting the disease. Black light traps were deployed at 36 outbreak sites and captured 1959 Culicoides specimens belonging to 16 different species. Eighty four percent of the biting midges captured belonged to the C. obsoletus complex, among them C. obsoletus s.s., C. dewulfi and C. scoticus, three suspected bluetongue vectors. The Veterinary and Agrochemical Research Centre detected viral RNA in pools of individuals belonging to this complex. Culicoides pulicaris, a potential bluetongue vector in Italy, should yet not be excluded as a possible vector in Belgium as this species was frequently found around outbreak sites, notwithstanding this species is not easily captured with the trapping techniques used during this survey.

  12. GAPS IN SUPPORT VECTOR OPTIMIZATION

    Energy Technology Data Exchange (ETDEWEB)

    STEINWART, INGO [Los Alamos National Laboratory; HUSH, DON [Los Alamos National Laboratory; SCOVEL, CLINT [Los Alamos National Laboratory; LIST, NICOLAS [Los Alamos National Laboratory

    2007-01-29

    We show that the stopping criteria used in many support vector machine (SVM) algorithms working on the dual can be interpreted as primal optimality bounds which in turn are known to be important for the statistical analysis of SVMs. To this end we revisit the duality theory underlying the derivation of the dual and show that in many interesting cases primal optimality bounds are the same as known dual optimality bounds.

  13. Ultrasonic Dynamic Vector Stress Sensor

    Science.gov (United States)

    Heyman, Joseph S.; Froggatt, Mark

    1992-01-01

    Stress inferred from measurements in specimens rather than in bonded gauges. Ultrasonic dynamic vector stress sensor (UDVSS) measures changes in dynamic directional stress occurring in material or structure at location touched by device when material or structure put under cyclic load. Includes phase-locked loop, synchronous amplifier, and contact probe. Useful among manufacturers of aerospace and automotive structures for stress testing and evaluation of designs.

  14. A ocean bottom vector magnetometer

    Science.gov (United States)

    Wang, Xiaomei; Teng, Yuntian; Wang, Chen; Ma, Jiemei

    2017-04-01

    The new development instrument with a compact spherical coil system and Overhauser magnetometer for measuring the total strength of the magnetic field and the vectors of strength, Delta inclination - Delta declination, meanwhile we also use a triaxial fluxgate instrument of the traditional instrument for geomagnetic vector filed measurement. The advantages of this method are be calibrated by each other and get good performances with automatic operation, good stability and high resolution. Firstly, a brief description of the instrument measurement principles and the key technologies are given. The instrument used a spherical coil system with 34 coils to product the homogeneous volume inside the coils which is large enough to accommodate the sensor of Overhauser total field sensor; the rest of the footlocker-sized ocean-bottom vector magnetometer consists of equipment to run the sensors and records its data (batteries and a data logger), weight to sink it to the sea floor, a remote-controlled acoustic release and flotation to bring the instrument back to the surface. Finally, the accuracy of the instrument was tested in the Geomagnetic station, and the measurement accuracies of total strength and components were better than 0.2nT and 1nT respectively. The figure 1 shows the development instrument structure. it includes six thick glass spheres which protect the sensor, data logger and batteries from the pressures of the deep sea, meanwhile they also provide recycling positive buoyancy; To cushion the glass, the spheres then go inside yellow plastic "hardhats". The triaxial fluxgate is inside No.1 glass spheres, data logger and batteries are inside No.2 glass spheres, the new vector sensor is inside No.3 glass spheres, acoustic communication unit is inside No.4 glass spheres, No.5 and No.6 glass spheres are empty which only provide recycling positive buoyancy. The figure 2 shows the development instrument Physical photo.

  15. Biological rhythms and vector insects

    Directory of Open Access Journals (Sweden)

    Mirian David Marques

    2013-01-01

    Full Text Available The adjustment of all species, animals and plants, to the Earth’s cyclic environments is ensured by their temporal organisation. The relationships between parasites, vectors and hosts rely greatly upon the synchronisation of their biological rhythms, especially circadian rhythms. In this short note, parasitic infections by Protozoa and by microfilariae have been chosen as examples of the dependence of successful transmission mechanisms on temporal components.

  16. Complementarity between the mRNA 5' untranslated region and 18S ribosomal RNA can inhibit translation.

    Science.gov (United States)

    Verrier, S B; Jean-Jean, O

    2000-04-01

    In eubacteria, base pairing between the 3' end of 16S rRNA and the ribosome-binding site of mRNA is required for efficient initiation of translation. An interaction between the 18S rRNA and the mRNA was also proposed for translation initiation in eukaryotes. Here, we used an antisense RNA approach in vivo to identify the regions of 18S rRNA that might interact with the mRNA 5' untranslated region (5' UTR). Various fragments covering the entire mouse 18S rRNA gene were cloned 5' of a cat reporter gene in a eukaryotic vector, and translation products were analyzed after transient expression in human cells. For the largest part of 18S rRNA, we show that the insertion of complementary fragments in the mRNA 5' UTR do not impair translation of the downstream open reading frame (ORF). When translation inhibition is observed, reduction of the size of the complementary sequence to less than 200 nt alleviates the inhibitory effect. A single fragment complementary to the 18S rRNA 3' domain retains its inhibitory potential when reduced to 100 nt. Deletion analyses show that two distinct sequences of approximately 25 nt separated by a spacer sequence of 50 nt are required for the inhibitory effect. Sucrose gradient fractionation of polysomes reveals that mRNAs containing the inhibitory sequences accumulate in the fractions with 40S ribosomal subunits, suggesting that translation is blocked due to stalling of initiation complexes. Our results support an mRNA-rRNA base pairing to explain the translation inhibition observed and suggest that this region of 18S rRNA is properly located for interacting with mRNA.

  17. Vector Fields and Flows on Differentiable Stacks

    DEFF Research Database (Denmark)

    A. Hepworth, Richard

    2009-01-01

    This paper introduces the notions of vector field and flow on a general differentiable stack. Our main theorem states that the flow of a vector field on a compact proper differentiable stack exists and is unique up to a uniquely determined 2-cell. This extends the usual result on the existence...... of vector fields....

  18. Project Physics Programmed Instruction, Vectors 3.

    Science.gov (United States)

    Harvard Univ., Cambridge, MA. Harvard Project Physics.

    This is the third of a series of three programmed instruction booklets on vectors developed by Harvard Project Physics. Separating vectors into components and obtaining a vector from its components are the topics covered. For other booklets in this series, see SE 015 549 and SE 015 550. (DT)

  19. Vector and tensor analysis with applications

    CERN Document Server

    Borisenko, A I; Silverman, Richard A

    1979-01-01

    Concise and readable, this text ranges from definition of vectors and discussion of algebraic operations on vectors to the concept of tensor and algebraic operations on tensors. It also includes a systematic study of the differential and integral calculus of vector and tensor functions of space and time. Worked-out problems and solutions. 1968 edition.

  20. Some Remarks on a Generalized Vector Product

    CERN Document Server

    Acosta-Humánez, Primitivo B; Núñez, Reinaldo

    2011-01-01

    In this paper we use a generalized vector product to construct an exterior form $\\wedge :(\\mathbb{R}^{n}) ^{k}\\to \\mathbb{R}^{\\binom{n}{k}}$, where $\\binom{n}{k}=\\frac{n!}{(n-k)!k!}$, $k\\leq n$. Finally, for $n=k-1$ we introduce the reversing operation to study this generalized vector product over palindromic and antipalindromic vectors.

  1. DNA甲基转移酶3b催化区保守序列shRNA真核表达载体构建%Construction of the eukaryotic expression vector carrying double shRNA sequence targeting the conserved domain of gene DNMT3b

    Institute of Scientific and Technical Information of China (English)

    张士龙; 曾甫清; 朱朝辉; 彭世波; 汪良; 董继华

    2008-01-01

    目的 构建针对基因DNA甲基转移酶3bmRNA催化区保守序列的shRNA真核表达载体,并对其克隆进行鉴定.方法 以DNMT3bmRNA序列为靶基因设计3条shRNA和一条阴性对照HK,应用基因重组技术将其克隆到真核表达载体Pgensil-1中,构建真核表达载体P-DNMT3b-shRNA1、P-DNMT3b-shRNA2、P-DNMT3b-shRNA3、P-HK.将重组质粒转化到大肠杆菌DH5α中,接种于LB平板后分别挑取5个单克隆菌落进行扩增,经筛选后对提取质粒进行测序鉴定.结果 重组质粒经SalⅠ酶切鉴定得到大小2个基因片段,大片段约为4.55kb,小片段约为440bp,与设计相同;四组重组质粒经测序鉴定显示插入完全正确.结论 成功构建了P-DNMT3b-shRNA(1、2、3)及HK真核表达载体,为下一步实验奠定了基础.

  2. On the Distribution of Norm of Vector Projection and Rejection of Two Complex Normal Random Vectors

    Directory of Open Access Journals (Sweden)

    Mehdi Maleki

    2015-01-01

    Full Text Available Vector projection and vector rejection are highly common and useful operations in mathematics, information theory, and signal processing. In this paper, we find the distribution of the norm of projection and rejection vectors when the original vectors are standard complex normally distributed.

  3. Vectors and Rotations in 3-Dimensions: Vector Algebra for the C++ Programmer

    Science.gov (United States)

    2016-12-01

    ARL-TR-7894•DEC 2016 US Army Research Laboratory Vectors and Rotations in 3-Dimensions:Vector Algebra for the C++ Programmer by Richard Saucier...Army Research Laboratory Vectors and Rotations in 3-Dimensions:Vector Algebra for the C++ Programmer by Richard Saucier Survivability/Lethality...

  4. RNA modifications by oxidation

    DEFF Research Database (Denmark)

    Poulsen, Henrik E; Specht, Elisabeth; Broedbaek, Kasper

    2012-01-01

    The past decade has provided exciting insights into a novel class of central (small) RNA molecules intimately involved in gene regulation. Only a small percentage of our DNA is translated into proteins by mRNA, yet 80% or more of the DNA is transcribed into RNA, and this RNA has been found...... to encompass various classes of novel regulatory RNAs, including, e.g., microRNAs. It is well known that DNA is constantly oxidized and repaired by complex genome maintenance mechanisms. Analogously, RNA also undergoes significant oxidation, and there are now convincing data suggesting that oxidation......, and the consequent loss of integrity of RNA, is a mechanism for disease development. Oxidized RNA is found in a large variety of diseases, and interest has been especially devoted to degenerative brain diseases such as Alzheimer disease, in which up to 50-70% of specific mRNA molecules are reported oxidized, whereas...

  5. New vectors for simple and streamlined CRISPR-Cas9 genome editing in Saccharomyces cerevisiae.

    Science.gov (United States)

    Laughery, Marian F; Hunter, Tierra; Brown, Alexander; Hoopes, James; Ostbye, Travis; Shumaker, Taven; Wyrick, John J

    2015-12-01

    Clustered regularly interspaced short palindromic repeats (CRISPR)-Cas9 technology is an important tool for genome editing because the Cas9 endonuclease can induce targeted DNA double-strand breaks. Targeting of the DNA break is typically controlled by a single-guide RNA (sgRNA), a chimeric RNA containing a structural segment important for Cas9 binding and a 20mer guide sequence that hybridizes to the genomic DNA target. Previous studies have demonstrated that CRISPR-Cas9 technology can be used for efficient, marker-free genome editing in Saccharomyces cerevisiae. However, introducing the 20mer guide sequence into yeast sgRNA expression vectors often requires cloning procedures that are complex, time-consuming and/or expensive. To simplify this process, we have developed a new sgRNA expression cassette with internal restriction enzyme sites that permit rapid, directional cloning of 20mer guide sequences. Here we describe a flexible set of vectors based on this design for cloning and expressing sgRNAs (and Cas9) in yeast using different selectable markers. We anticipate that the Cas9-sgRNA expression vector with the URA3 selectable marker (pML104) will be particularly useful for genome editing in yeast, since the Cas9 machinery can be easily removed by counter-selection using 5-fluoro-orotic acid (5-FOA) following successful genome editing. The availability of new vectors that simplify and streamline the technical steps required for guide sequence cloning should help accelerate the use of CRISPR-Cas9 technology in yeast genome editing.

  6. Coordinate enhancement of transgene transcription and translation in a lentiviral vector

    Directory of Open Access Journals (Sweden)

    Fernandez Soledad

    2006-02-01

    Full Text Available Abstract Background Coordinate enhancement of transgene transcription and translation would be a potent approach to significantly improve protein output in a broad array of viral vectors and nonviral expression systems. Many vector transgenes are complementary DNA (cDNA. The lack of splicing can significantly reduce the efficiency of their translation. Some retroviruses contain a 5' terminal post-transcriptional control element (PCE that facilitates translation of unspliced mRNA. Here we evaluated the potential for spleen necrosis virus PCE to stimulate protein production from HIV-1 based lentiviral vector by: 1 improving translation of the internal transgene transcript; and 2 functionally synergizing with a transcriptional enhancer to achieve coordinate increases in RNA synthesis and translation. Results Derivatives of HIV-1 SIN self-inactivating lentiviral vector were created that contain PCE and cytomegalovirus immediate early enhancer (CMV IE. Results from transfected cells and four different transduced cell types indicate that: 1 PCE enhanced transgene protein synthesis; 2 transcription from the internal promoter is enhanced by CMV IE; 3 PCE and CMV IE functioned synergistically to significantly increase transgene protein yield; 4 the magnitude of translation enhancement by PCE was similar in transfected and transduced cells; 5 differences were observed in steady state level of PCE vector RNA in transfected and transduced cells; 6 the lower steady state was not attributable to reduced RNA stability, but to lower cytoplasmic accumulation in transduced cells. Conclusion PCE is a useful tool to improve post-transcriptional expression of lentiviral vector transgene. Coordinate enhancement of transcription and translation is conferred by the combination of PCE with CMV IE transcriptional enhancer and increased protein yield up to 11 to 17-fold in transfected cells. The incorporation of the vector provirus into chromatin correlated with reduced

  7. Overcoming HIV-1 resistance to RNA interference.

    Science.gov (United States)

    Boden, Daniel; Pusch, Oliver; Ramratnam, Bharat

    2007-05-01

    RNAi refers to the sequence-specific degradation of RNA that follows the cellular introduction of homologous short interfering (si) RNA. RNAi has emerged as a powerful tool to probe the function of genes of known sequence in vitro and in vivo. Advances in vector design permit the effective expression of siRNA in human cells. Numerous recent investigations have described the ability of RNAi to decrease the replication of human immunodeficiency virus type 1 (HIV-1) in lymphocytic cells using siRNA targeting viral (e.g. tat, gag, rev) and host (e.g. CCR5, CD4) proteins. Can RNAi be used as a form of genetic therapy for HIV-1 infection? Recent data indicate that the dynamic replication kinetics of HIV-1 pose a considerable barrier to achieving durable virus suppression by RNAi with the rapid emergence of HIV-1 mutants resistant to siRNA. This review summarizes recent work on HIV-1 specific RNAi with a focus on potential strategies to overcome HIV-1 resistance to RNAi.

  8. Target-cell-derived tRNA-like primers for reverse transcription support retroviral infection at low efficiency

    DEFF Research Database (Denmark)

    Schmitz, Alexander; Lund, Anders H; Hansen, Anette C

    2002-01-01

    by cases of correction of single mismatches between Akv-MLV vectors and complementary tRNA primers toward the primer sequence in the integrated vector. Thus, target-cell-derived tRNA-like primers are able to initiate first-strand cDNA synthesis and plus-strand transfer leading to a complete provirus......RNA primers derived from the target cell can sustain reverse transcription during murine leukemia virus (MLV) infection. Transduction efficiencies were 4-5 orders of magnitude below those of comparable producer-cell complementations. However, successful usage of a target-cell-derived tRNA primer was proven...

  9. Augmenting CRISPR applications in Drosophila with tRNA-flanked sgRNAs.

    Science.gov (United States)

    Port, Fillip; Bullock, Simon L

    2016-10-01

    We present tRNA-based vectors for producing multiple clustered regularly interspaced short palindromic repeats (CRISPR) single guide RNAs (sgRNAs) from a single RNA polymerase II or III transcript in Drosophila. The system, which is based on liberation of sgRNAs by processing flanking tRNAs, permits highly efficient multiplexing of Cas9-based mutagenesis. We also demonstrate that the tRNA-sgRNA system markedly increases the efficacy of conditional gene disruption by Cas9 and can promote editing by the recently discovered RNA-guided endonuclease Cpf1.

  10. Problems and worked solutions in vector analysis

    CERN Document Server

    Shorter, LR

    2014-01-01

    ""A handy book like this,"" noted The Mathematical Gazette, ""will fill a great want."" Devoted to fully worked out examples, this unique text constitutes a self-contained introductory course in vector analysis for undergraduate and graduate students of applied mathematics.Opening chapters define vector addition and subtraction, show how to resolve and determine the direction of two or more vectors, and explain systems of coordinates, vector equations of a plane and straight line, relative velocity and acceleration, and infinitely small vectors. The following chapters deal with scalar and vect

  11. Working with RNA

    DEFF Research Database (Denmark)

    Nielsen, Henrik

    2011-01-01

    Working with RNA is not a special discipline in molecular biology. However, RNA is chemically and structurally different from DNA and a few simple work rules have to be implemented to maintain the integrity of the RNA. Alkaline pH, high temperatures, and heavy metal ions should be avoided when po...

  12. RNA self-assembly and RNA nanotechnology.

    Science.gov (United States)

    Grabow, Wade W; Jaeger, Luc

    2014-06-17

    CONSPECTUS: Nanotechnology's central goal involves the direct control of matter at the molecular nanometer scale to build nanofactories, nanomachines, and other devices for potential applications including electronics, alternative fuels, and medicine. In this regard, the nascent use of nucleic acids as a material to coordinate the precise arrangements of specific molecules marked an important milestone in the relatively recent history of nanotechnology. While DNA served as the pioneer building material in nucleic acid nanotechnology, RNA continues to emerge as viable alternative material with its own distinct advantages for nanoconstruction. Several complementary assembly strategies have been used to build a diverse set of RNA nanostructures having unique structural attributes and the ability to self-assemble in a highly programmable and controlled manner. Of the different strategies, the architectonics approach uniquely endeavors to understand integrated structural RNA architectures through the arrangement of their characteristic structural building blocks. Viewed through this lens, it becomes apparent that nature routinely uses thermodynamically stable, recurrent modular motifs from natural RNA molecules to generate unique and more complex programmable structures. With the design principles found in natural structures, a number of synthetic RNAs have been constructed. The synthetic nanostructures constructed to date have provided, in addition to affording essential insights into RNA design, important platforms to characterize and validate the structural self-folding and assembly properties of RNA modules or building blocks. Furthermore, RNA nanoparticles have shown great promise for applications in nanomedicine and RNA-based therapeutics. Nevertheless, the synthetic RNA architectures achieved thus far consist largely of static, rigid particles that are still far from matching the structural and functional complexity of natural responsive structural elements such

  13. Noncoding Subgenomic Flavivirus RNA Is Processed by the Mosquito RNA Interference Machinery and Determines West Nile Virus Transmission by Culex pipiens Mosquitoes.

    Science.gov (United States)

    Göertz, G P; Fros, J J; Miesen, P; Vogels, C B F; van der Bent, M L; Geertsema, C; Koenraadt, C J M; van Rij, R P; van Oers, M M; Pijlman, G P

    2016-11-15

    Flaviviruses, such as Zika virus, yellow fever virus, dengue virus, and West Nile virus (WNV), are a serious concern for human health. Flaviviruses produce an abundant noncoding subgenomic flavivirus RNA (sfRNA) in infected cells. sfRNA results from stalling of the host 5'-3' exoribonuclease XRN1/Pacman on conserved RNA structures in the 3' untranslated region (UTR) of the viral genomic RNA. sfRNA production is conserved in insect-specific, mosquito-borne, and tick-borne flaviviruses and flaviviruses with no known vector, suggesting a pivotal role for sfRNA in the flavivirus life cycle. Here, we investigated the function of sfRNA during WNV infection of Culex pipiens mosquitoes and evaluated its role in determining vector competence. An sfRNA1-deficient WNV was generated that displayed growth kinetics similar to those of wild-type WNV in both RNA interference (RNAi)-competent and -compromised mosquito cell lines. Small-RNA deep sequencing of WNV-infected mosquitoes indicated an active small interfering RNA (siRNA)-based antiviral response for both the wild-type and sfRNA1-deficient viruses. Additionally, we provide the first evidence that sfRNA is an RNAi substrate in vivo Two reproducible small-RNA hot spots within the 3' UTR/sfRNA of the wild-type virus mapped to RNA stem-loops SL-III and 3' SL, which stick out of the three-dimensional (3D) sfRNA structure model. Importantly, we demonstrate that sfRNA-deficient WNV displays significantly decreased infection and transmission rates in vivo when administered via the blood meal. Finally, we show that transmission and infection rates are not affected by sfRNA after intrathoracic injection, thereby identifying sfRNA as a key driver to overcome the mosquito midgut infection barrier. This is the first report to describe a key biological function of sfRNA for flavivirus infection of the arthropod vector, providing an explanation for the strict conservation of sfRNA production. Understanding the flavivirus transmission

  14. DBSC-Based Grayscale Line Image Vectorization

    Institute of Scientific and Technical Information of China (English)

    Konstantin Melikhov; Feng Tian; Jie Qiu; Quan Chen; Hock Soon Seah

    2006-01-01

    Vector graphics plays an important role in computer animation and imaging technologies. However present techniques and tools cannot fully replace traditional pencil and paper. Additionally, vector representation of an image is not always available. There is not yet a good solution for vectorizing a picture drawn on a paper. This work attempts to solve the problem of vectorizing grayscale line drawings. The solution proposed uses Disk B-Spline curves to represent strokes of an image in vector form. The algorithm builds a vector representation from a grayscale raster image, which can be a scanned picture for instance. The proposed method uses a Gaussian sliding window to calculate skeleton and perceptive width of a stroke. As a result of vectorization, the given image is represented by a set of Disk B-Spline curves.

  15. Transversals of Complex Polynomial Vector Fields

    DEFF Research Database (Denmark)

    Dias, Kealey

    , an important step was proving that the transversals possessed a certain characteristic. Understanding transversals might be the key to proving other polynomial vector fields are generic, and they are important in understanding bifurcations of polynomial vector fields in general. We consider two important......Vector fields in the complex plane are defined by assigning the vector determined by the value P(z) to each point z in the complex plane, where P is a polynomial of one complex variable. We consider special families of so-called rotated vector fields that are determined by a polynomial multiplied...... a concrete polynomial, it seems to take quite a bit of work to prove that it is generic, i.e. structurally stable. This has been done for a special class of degree d polynomial vector fields having simple equilibrium points at the d roots of unity, d odd. In proving that such vector fields are generic...

  16. Transversals of Complex Polynomial Vector Fields

    DEFF Research Database (Denmark)

    Dias, Kealey

    by rotational constants. Transversals are a certain class of curves for such a family of vector fields that represent the bifurcation states for this family of vector fields. More specifically, transversals are curves that coincide with a homoclinic separatrix for some rotation of the vector field. Given......Vector fields in the complex plane are defined by assigning the vector determined by the value P(z) to each point z in the complex plane, where P is a polynomial of one complex variable. We consider special families of so-called rotated vector fields that are determined by a polynomial multiplied...... examples of rotated families to argue this. There will be discussed several open questions concerning the number of transversals that can appear for a certain degree d of a polynomial vector field, and furthermore how transversals are analyzed with respect to bifurcations around multiple equilibrium points....

  17. The vector algebra war: A historical perspective

    CERN Document Server

    Chappell, James M; Hartnett, John G; Abbott, Derek

    2015-01-01

    There are a wide variety of different vector formalisms currently utilized in science. For example, Gibbs three-vectors, spacetime four-vectors, complex spinors for quantum mechanics, quaternions used for rigid body rotations and Clifford multivectors. With such a range of vector formalisms in use, it thus appears that there is as yet no general agreement on a vector formalism suitable for the whole of science. This surprising situation exists today, despite the fact that one of the main goals of nineteenth century science was to correctly describe vectors and the algebra of three-dimensional space. This situation has also had the unfortunate consequence of fragmenting knowledge across many disciplines and requiring a very significant amount of time and effort in learning the different formalisms. We thus review historically the development of our various vector systems and conclude that the Clifford algebra multivector fulfills the goal of correctly describing vectorial quantities in three dimensions.

  18. Culex pipiens quinquefasciatus: a potential vector to transmit Zika virus.

    Science.gov (United States)

    Guo, Xiao-Xia; Li, Chun-Xiao; Deng, Yong-Qiang; Xing, Dan; Liu, Qin-Mei; Wu, Qun; Sun, Ai-Juan; Dong, Yan-de; Cao, Wu-Chun; Qin, Cheng-Feng; Zhao, Tong-Yan

    2016-09-07

    Zika virus (ZIKV) has become a threat to global health since the outbreak in Brazil in 2015. Although ZIKV is generally considered an Aedes-transmitted pathogen, new evidence has shown that parts of the virus closely resemble Culex-transmitted viruses. Therefore, it is important to evaluate the competence of Culex species for ZIKV to understand their potential as vectors. In this study, female Culex pipiens quinquefasciatus were orally exposed to ZIKV. Mosquito midguts, salivary glands and ovaries were tested for ZIKV to measure infection and dissemination at 2, 4, 6, 8, 12, 16 and 18 days post exposure (pe). In addition, saliva was collected from mosquitoes after infection and infant mice were bitten by infected mosquitoes to measure the transmission ability of Cx. p. quinquefasciatus. The results showed that the peak time of virus appearance in the salivary glands was day 8 pe, with 90% infection rate and an estimated virus titer of 3.92±0.49 lg RNA copies/mL. Eight of the nine infant mice had positive brains after being bitten by infected mosquitoes, which meant that Cx. p. quinquefasciatus could be infected with and transmit ZIKV following oral infection. These laboratory results clearly demonstrate the potential role of Cx. p. quinquefasciatus as a vector of ZIKV in China. Because there are quite different vector management strategies required to control Aedes (Stegomyia) species and Cx. p. quinquefasciatus, an integrated approach may be required should a Zika epidemic occur.

  19. Modified gateway system for double shRNA expression and Cre/lox based gene expression

    Directory of Open Access Journals (Sweden)

    Leung Lisa

    2011-03-01

    Full Text Available Abstract Background The growing need for functional studies of genes has set the stage for the development of versatile tools for genetic manipulations. Results Aiming to provide tools for high throughput analysis of gene functions, we have developed a modified short hairpin RNA (shRNA and gene expression system based on Gateway Technology. The system contains a series of entry and destination vectors that enables easy transfer of shRNA or cDNA into lentiviral expression systems with a variety of selection or marker genes (i.e. puromycin, hygromycin, green fluorescent protein-EGFP, yellow fluorescent protein-YFP and red fluorescent protein-dsRed2. Our shRNA entry vector pENTR.hU6.hH1 containing two tandem human shRNA expression promoters, H1 and U6, was capable of co-expressing two shRNA sequences simultaneously. The entry vector for gene overexpression, pENTR.CMV.ON was constructed to contain CMV promoter with a multiple cloning site flanked by loxP sites allowing for subsequent Cre/lox recombination. Both shRNA and cDNA expression vectors also contained attL sites necessary for recombination with attR sites in our destination expression vectors. As proof of principle we demonstrate the functionality and efficiency of this system by testing expression of several cDNA and shRNA sequences in a number of cell lines. Conclusion Our system is a valuable addition to already existing library of Gateway based vectors and can be an essential tool for many aspects of gene functional studies.

  20. Some theoretical comparisons of refined Ritz vectors and Ritz vectors

    Institute of Scientific and Technical Information of China (English)

    JIA Zhongxiao

    2004-01-01

    Refined projection methods proposed by the author have received attention internationally. We are concerned with a conventional projection method and its refined counterpart for computing approximations to a simple eigenpair (λ,x)of a large matrix A. Given a subspace w that contains anapproximation to x, these two methods compute approximations(μ(x~)) and (μ(x^)) to (λ,x),respectively. We establish three results. First, the refinedeigenvector approximation or simply the refined Ritz vector (x^) is unique as the deviation of x from w approaches zero if λ is simple. Second, interms of residual norm of the refined approximate eigenpair (μ,(x^)), we derive lower and upper bounds for the sine of the angle betweenthe Ritz vector (x~) and the refined eigenvector approximation (x^), and we prove that (x~)≠(x^) unless (x^)=x. Third, we establish relationships between theresidual norm ‖A(x~)-μ(x^)‖ of the conventionalmethods and the residual norm ‖A(x^)-μ(x^)‖ of therefined methods, and we show that the latter is always smallerthan the former if (μ,(x^)) is not an exact eigenpair ofA, indicating that the refined projection method is superiorto the corresponding conventional counterpart.

  1. Some theoretical comparisons of refined Ritz vectors and Ritz vectors

    Institute of Scientific and Technical Information of China (English)

    JIA; Zhongxiao

    2004-01-01

    Refined projection methods proposed by the author have received attention internationally. We are concerned with a conventional projection method and its refined counterpart for computing approximations to a simple eigenpair (λ,x)of a large matrix A. Given a subspace w that contains anapproximation to x, these two methods compute approximations(μ(x~)) and (μ(x)) to (λ,x),respectively. We establish three results. First, the refinedeigenvector approximation or simply the refined Ritz vector (x) is unique as the deviation of x from w approaches zero if λ is simple. Second, interms of residual norm of the refined approximate eigenpair (μ,(x)), we derive lower and upper bounds for the sine of the angle betweenthe Ritz vector (x~) and the refined eigenvector approximation (x), and we prove that (x~)≠(x) unless (x)=x. Third, we establish relationships between theresidual norm ‖A(x~)-μ(x)‖ of the conventionalmethods and the residual norm ‖A(x)-μ(x)‖ of therefined methods, and we show that the latter is always smallerthan the former if (μ,(x)) is not an exact eigenpair ofA, indicating that the refined projection method is superiorto the corresponding conventional counterpart.

  2. Combinatorics of RNA-RNA interaction.

    Science.gov (United States)

    Li, Thomas J X; Reidys, Christian M

    2012-02-01

    RNA-RNA binding is an important phenomenon observed for many classes of non-coding RNAs and plays a crucial role in a number of regulatory processes. Recently several MFE folding algorithms for predicting the joint structure of two interacting RNA molecules have been proposed. Here joint structure means that in a diagram representation the intramolecular bonds of each partner are pseudoknot-free, that the intermolecular binding pairs are noncrossing, and that there is no so-called "zigzag" configuration. This paper presents the combinatorics of RNA interaction structures including their generating function, singularity analysis as well as explicit recurrence relations. In particular, our results imply simple asymptotic formulas for the number of joint structures.

  3. Combinatorics of RNA-RNA interaction

    CERN Document Server

    Li, Thomas J X

    2010-01-01

    RNA-RNA binding is an important phenomenon observed for many classes of non-coding RNAs and plays a crucial role in a number of regulatory processes. Recently several MFE folding algorithms for predicting the joint structure of two interacting RNA molecules have been proposed. Here joint structure means that in a diagram representation the intramolecular bonds of each partner are pseudoknot-free, that the intermolecular binding pairs are noncrossing, and that there is no so-called ``zig-zag'' configuration. This paper presents the combinatorics of RNA interaction structures including their generating function, singularity analysis as well as explicit recurrence relations. In particular, our results imply simple asymptotic formulas for the number of joint structures.

  4. Vector meson electroproduction in QCD

    Institute of Scientific and Technical Information of China (English)

    LU Juan; CAI Xian-Hao; ZHOU Li-Juan

    2012-01-01

    Based on the generalized QCD vector meson dominance model,we study the electroproduction of a vector meson off a proton in the QCD inspired eikonalized model.Numerical calculations for the total cross section σtot and differential cross section dσ/dt are performed for p,ω and φ meson electroproduction in this paper.Since gluons interact among themselves (self-interaction),two gluons can form a glueball with quantum numbers IG,JPC =0+,2++,decay width Γt ≈ 100 MeV,and mass of mG=2.23 GeV.The three gluons can form a three-gluon colorless bound state with charge conjugation quantum number C =-1,called the Odderon.The mediators of interactions between projectiles (the quark and antiquark pair fluctuated from the virtual photon) and the proton target (a three-quark system) are the tensor glueball and the Odderon.Our calculated results in the tensor glueball and Odderon exchange model fit to the existing data successfully,which evidently shows that our present QCD mechanism is a good description of meson electroproduction off a proton.It should be emphasized that our mechanism is different from the theoretical framework of Block et al.We also believe that the present study and its success are important for the investigation of other vector meson electro- and photoproduction at high energies,as well as for searching for new particles such as tensor glueballs and Odderons,which have been predicted by QCD and the color glass condensate model (CGC).Therefore,in return,it can test the validity of QCD and the CGC model.

  5. Vector meson electroproduction in QCD

    Science.gov (United States)

    Lu, Juan; Cai, Xian-Hao; Zhou, Li-Juan

    2012-08-01

    Based on the generalized QCD vector meson dominance model, we study the electroproduction of a vector meson off a proton in the QCD inspired eikonalized model. Numerical calculations for the total cross section σtot and differential cross section dσ/dt are performed for ρ, ω and varphi meson electroproduction in this paper. Since gluons interact among themselves (self-interaction), two gluons can form a glueball with quantum numbers IG, JPC = 0+,2++, decay width Γt ≈ 100 MeV, and mass of mG = 2.23 GeV. The three gluons can form a three-gluon colorless bound state with charge conjugation quantum number C = -1, called the Odderon. The mediators of interactions between projectiles (the quark and antiquark pair fluctuated from the virtual photon) and the proton target (a three-quark system) are the tensor glueball and the Odderon. Our calculated results in the tensor glueball and Odderon exchange model fit to the existing data successfully, which evidently shows that our present QCD mechanism is a good description of meson electroproduction off a proton. It should be emphasized that our mechanism is different from the theoretical framework of Block et al. We also believe that the present study and its success are important for the investigation of other vector meson electro- and photoproduction at high energies, as well as for searching for new particles such as tensor glueballs and Odderons, which have been predicted by QCD and the color glass condensate model (CGC). Therefore, in return, it can test the validity of QCD and the CGC model.

  6. Lentiviral Vector Mediated Claudin1 Silencing Inhibits Epithelial to Mesenchymal Transition in Breast Cancer Cells

    Directory of Open Access Journals (Sweden)

    Xianqi Zhao

    2015-06-01

    Full Text Available Breast cancer has a high incidence and mortality rate worldwide. Several viral vectors including lentiviral, adenoviral and adeno-associated viral vectors have been used in gene therapy for various forms of human cancer, and have shown promising effects in controlling tumor development. Claudin1 (CLDN1 is a member of the tetraspan transmembrane protein family that plays a major role in tight junctions and is associated with tumor metastasis. However, the role of CLDN1 in breast cancer is largely unexplored. In this study, we tested the therapeutic potential of silencing CLDN1 expression in two breast cancer (MDA-MB-231 and MCF7 cell lines using lentiviral vector mediated RNA interference. We found that a CLDN1 short hairpin (shRNA construct efficiently silenced CLDN1 expression in both breast cancer cell lines, and CLDN1 knockdown resulted in reduced cell proliferation, survival, migration and invasion. Furthermore, silencing CLDN1 inhibited epithelial to mesenchymal transition (EMT by upregulating the epithelial cell marker, E-cadherin, and downregulating mesenchymal markers, smooth muscle cell alpha-actin (SMA and Snai2. Our data demonstrated that lentiviral vector mediated CLDN1 RNA interference has great potential in breast cancer gene therapy by inhibiting EMT and controlling tumor cell growth.

  7. On Weighted Support Vector Regression

    DEFF Research Database (Denmark)

    Han, Xixuan; Clemmensen, Line Katrine Harder

    2014-01-01

    We propose a new type of weighted support vector regression (SVR), motivated by modeling local dependencies in time and space in prediction of house prices. The classic weights of the weighted SVR are added to the slack variables in the objective function (OF‐weights). This procedure directly...... the differences and similarities of the two types of weights by demonstrating the connection between the Least Absolute Shrinkage and Selection Operator (LASSO) and the SVR. We show that an SVR problem can be transformed to a LASSO problem plus a linear constraint and a box constraint. We demonstrate...

  8. Probability Ranking in Vector Spaces

    CERN Document Server

    Melucci, Massimo

    2011-01-01

    The Probability Ranking Principle states that the document set with the highest values of probability of relevance optimizes information retrieval effectiveness given the probabilities are estimated as accurately as possible. The key point of the principle is the separation of the document set into two subsets with a given level of fallout and with the highest recall. The paper introduces the separation between two vector subspaces and shows that the separation yields a more effective performance than the optimal separation into subsets with the same available evidence, the performance being measured with recall and fallout. The result is proved mathematically and exemplified experimentally.

  9. Cytoplasmic Z-RNA

    Energy Technology Data Exchange (ETDEWEB)

    Zarling, D.A.; Calhoun, C.J.; Hardin, C.C.; Zarling, A.H.

    1987-09-01

    Specific immunochemical probes for Z-RNA were generated and characterized to search for possible Z-RNA-like double helices in cells. Z-RNA was detected in the cytoplasm of fixed protozoan cells by immunofluorescence microscopy using these anti-Z-RNA IgCs. In contrast, autoimmune or experimentally elicited anti-DNA antibodies, specifically reactive with B-DNA or Z-DNA, stained the nuclei. Pre-or nonimmune IgGs did not bind to the cells. RNase A or T1 digestion eliminated anti-Z-RNA IgG binding to cytoplasmic determinants; however, DNase I or mung bean nuclease had no effect. Doxorubicin and ethidium bromide prevented anti-Z-RNA antibody binding; however, actinomycin D, which does not bind double-stranded RNA, did not. Anti-Z-RNA immunofluorescence was specifically blocked in competition assays by synthetic Z-RNA but not Z-DNA, A-RNA, or single-stranded RNAs. Thus, some cytoplasmic sequences in fixed cells exist in the left-handed Z-RNA conformation.

  10. Raman crystallography of RNA.

    Science.gov (United States)

    Gong, Bo; Chen, Jui-Hui; Yajima, Rieko; Chen, Yuanyuan; Chase, Elaine; Chadalavada, Durga M; Golden, Barbara L; Carey, Paul R; Bevilacqua, Philip C

    2009-10-01

    Raman crystallography is the application of Raman spectroscopy to single crystals. This technique has been applied to a variety of protein molecules where it has provided unique information about biopolymer folding, substrate binding, and catalysis. Here, we describe the application of Raman crystallography to functional RNA molecules. RNA represents unique opportunities and challenges for Raman crystallography. One issue that confounds studies of RNA is its tendency to adopt multiple non-functional folds. Raman crystallography has the advantage that it isolates a single state of the RNA within the crystal and can evaluate its fold, metal ion binding properties (ligand identity, stoichiometry, and affinity), proton binding properties (identity, stoichiometry, and affinity), and catalytic potential. In particular, base-specific stretches can be identified and then associated with the binding of metal ions and protons. Because measurements are carried out in the hanging drop at ambient, rather than cryo, conditions and because RNA crystals tend to be approximately 70% solvent, RNA dynamics and conformational changes become experimentally accessible. This review focuses on experimental setup and procedures, acquisition and interpretation of Raman data, and determination of physicochemical properties of the RNA. Raman crystallographic and solution biochemical experiments on the HDV RNA enzyme are summarized and found to be in excellent agreement. Remarkably, characterization of the crystalline state has proven to help rather than hinder functional characterization of functional RNA, most likely because the tendency of RNA to fold heterogeneously is limited in a crystalline environment. Future applications of Raman crystallography to RNA are briefly discussed.

  11. Methods for RNA Analysis

    DEFF Research Database (Denmark)

    Olivarius, Signe

    of the transcriptome, 5’ end capture of RNA is combined with next-generation sequencing for high-throughput quantitative assessment of transcription start sites by two different methods. The methods presented here allow for functional investigation of coding as well as noncoding RNA and contribute to future......While increasing evidence appoints diverse types of RNA as key players in the regulatory networks underlying cellular differentiation and metabolism, the potential functions of thousands of conserved RNA structures encoded in mammalian genomes remain to be determined. Since the functions of most...... RNAs rely on interactions with proteins, the establishment of protein-binding profiles is essential for the characterization of RNAs. Aiming to facilitate RNA analysis, this thesis introduces proteomics- as well as transcriptomics-based methods for the functional characterization of RNA. First, RNA...

  12. Gene Cloning of Murine α-Fetoprotein Gene and Construction of Its Eukaryotic Expression Vector and Expression in CHO Cells

    Institute of Scientific and Technical Information of China (English)

    易继林; 田耕

    2003-01-01

    To clone the murine α-fetoprotein (AFP) gene, construct the eukaryotic expression vector of AFP and express in CHO cells, total RNA were extracted from Hepa 1-6 cells, and then the murine α-fetoprotein gene was amplified by RT-PCR and cloned into the eukaryotic expression vector pcDNA3.1. The recombinant of vector was identified by restriction enzyme analysis and sequencing. A fter transient transfection of CHO cells with the vector, Western blotting was used to detect the expression of AFP. It is concluded that the 1.8kb murine α-fetoprotein gene was successfully cloned and its eukaryotic expression vector was successfully constructed.

  13. Vector-tensor and vector-vector decay amplitude analysis of B0-->phiK*0.

    Science.gov (United States)

    Aubert, B; Bona, M; Boutigny, D; Couderc, F; Karyotakis, Y; Lees, J P; Poireau, V; Tisserand, V; Zghiche, A; Grauges, E; Palano, A; Chen, J C; Qi, N D; Rong, G; Wang, P; Zhu, Y S; Eigen, G; Ofte, I; Stugu, B; Abrams, G S; Battaglia, M; Brown, D N; Button-Shafer, J; Cahn, R N; Charles, E; Gill, M S; Groysman, Y; Jacobsen, R G; Kadyk, J A; Kerth, L T; Kolomensky, Yu G; Kukartsev, G; Pegna, D Lopes; Lynch, G; Mir, L M; Orimoto, T J; Pripstein, M; Roe, N A; Ronan, M T; Wenzel, W A; Sanchez, P del Amo; Barrett, M; Ford, K E; Harrison, T J; Hart, A J; Hawkes, C M; Watson, A T; Held, T; Koch, H; Lewandowski, B; Pelizaeus, M; Peters, K; Schroeder, T; Steinke, M; Boyd, J T; Burke, J P; Cottingham, W N; Walker, D; Asgeirsson, D J; Cuhadar-Donszelmann, T; Fulsom, B G; Hearty, C; Knecht, N S; Mattison, T S; McKenna, J A; Khan, A; Kyberd, P; Saleem, M; Sherwood, D J; Teodorescu, L; Blinov, V E; Bukin, A D; Druzhinin, V P; Golubev, V B; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Todyshev, K Yu; Best, D S; Bondioli, M; Bruinsma, M; Chao, M; Curry, S; Eschrich, I; Kirkby, D; Lankford, A J; Lund, P; Mandelkern, M; Roethel, W; Stoker, D P; Abachi, S; Buchanan, C; Foulkes, S D; Gary, J W; Long, O; Shen, B C; Wang, K; Zhang, L; Hadavand, H K; Hill, E J; Paar, H P; Rahatlou, S; Sharma, V; Berryhill, J W; Campagnari, C; Cunha, A; Dahmes, B; Hong, T M; Kovalskyi, D; Richman, J D; Beck, T W; Eisner, A M; Flacco, C J; Heusch, C A; Kroseberg, J; Lockman, W S; Nesom, G; Schalk, T; Schumm, B A; Seiden, A; Spradlin, P; Williams, D C; Wilson, M G; Albert, J; Chen, E; Cheng, C H; Dvoretskii, A; Fang, F; Hitlin, D G; Narsky, I; Piatenko, T; Porter, F C; Mancinelli, G; Meadows, B T; Mishra, K; Sokoloff, M D; Blanc, F; Bloom, P C; Chen, S; Ford, W T; Hirschauer, J F; Kreisel, A; Nagel, M; Nauenberg, U; Olivas, A; Ruddick, W O; Smith, J G; Ulmer, K A; Wagner, S R; Zhang, J; Chen, A; Eckhart, E A; Soffer, A; Toki, W H; Wilson, R J; Winklmeier, F; Zeng, Q; Altenburg, D D; Feltresi, E; Hauke, A; Jasper, H; Merkel, J; Petzold, A; Spaan, B; Brandt, T; Klose, V; Lacker, H M; Mader, W F; Nogowski, R; Schubert, J; Schubert, K R; Schwierz, R; Sundermann, J E; Volk, A; Bernard, D; Bonneaud, G R; Latour, E; Thiebaux, Ch; Verderi, M; Clark, P J; Gradl, W; Muheim, F; Playfer, S; Robertson, A I; Xie, Y; Andreotti, M; Bettoni, D; Bozzi, C; Calabrese, R; Cibinetto, G; Luppi, E; Negrini, M; Petrella, A; Piemontese, L; Prencipe, E; Anulli, F; Baldini-Ferroli, R; Calcaterra, A; de Sangro, R; Finocchiaro, G; Pacetti, S; Patteri, P; Peruzzi, I M; Piccolo, M; Rama, M; Zallo, A; Buzzo, A; Contri, R; Vetere, M Lo; Macri, M M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Brandenburg, G; Chaisanguanthum, K S; Lee, C L; Morii, M; Wu, J; Dubitzky, R S; Marks, J; Schenk, S; Uwer, U; Bard, D J; Bhimji, W; Bowerman, D A; Dauncey, P D; Egede, U; Flack, R L; Nash, J A; Nikolich, M B; Vazquez, W Panduro; Behera, P K; Chai, X; Charles, M J; Mallik, U; Meyer, N T; Ziegler, V; Cochran, J; Crawley, H B; Dong, L; Eyges, V; Meyer, W T; Prell, S; Rosenberg, E I; Rubin, A E; Gao, Y; Gritsan, A V; Guo, Z J; Denig, A G; Fritsch, M; Schott, G; Arnaud, N; Davier, M; Grosdidier, G; Höcker, A; Lepeltier, V; Diberder, F Le; Lutz, A M; Oyanguren, A; Pruvot, S; Rodier, S; Roudeau, P; Schune, M H; Serrano, J; Stocchi, A; Wang, W F; Wormser, G; Lange, D J; Wright, D M; Chavez, C A; Forster, I J; Fry, J R; Gabathuler, E; Gamet, R; George, K A; Hutchcroft, D E; Payne, D J; Schofield, K C; Touramanis, C; Bevan, A J; Clarke, C K; Lodovico, F Di; Menges, W; Sacco, R; Cowan, G; Flaecher, H U; Hopkins, D A; Jackson, P S; McMahon, T R; Salvatore, F; Wren, A C; Brown, D N; Davis, C L; Allison, J; Barlow, N R; Barlow, R J; Chia, Y M; Edgar, C L; Lafferty, G D; Naisbit, M T; Williams, J C; Yi, J I; Chen, C; Hulsbergen, W D; Jawahery, A; Lae, C K; Roberts, D A; Simi, G; Blaylock, G; Dallapiccola, C; Hertzbach, S S; Li, X; Moore, T B; Saremi, S; Staengle, H; Cowan, R; Sciolla, G; Sekula, S J; Spitznagel, M; Taylor, F; Yamamoto, R K; Kim, H; McLachlin, S E; Patel, P M; Robertson, S H; Lazzaro, A; Lombardo, V; Palombo, F; Bauer, J M; Cremaldi, L; Eschenburg, V; Godang, R; Kroeger, R; Sanders, D A; Summers, D J; Zhao, H W; Brunet, S; Côté, D; Simard, M; Taras, P; Viaud, F B; Nicholson, H; Cavallo, N; Nardo, G De; Fabozzi, F; Gatto, C; Lista, L; Monorchio, D; Paolucci, P; Piccolo, D; Sciacca, C; Baak, M A; Raven, G; Snoek, H L; Jessop, C P; Losecco, J M; Benelli, G; Corwin, L A; Gan, K K; Honscheid, K; Hufnagel, D; Jackson, P D; Kagan, H; Kass, R; Rahimi, A M; Regensburger, J J; Ter-Antonyan, R; Wong, Q K; Blount, N L; Brau, J; Frey, R; Igonkina, O; Kolb, J A; Lu, M; Potter, C T; Rahmat, R; Sinev, N B; Strom, D; Strube, J; Torrence, E; Gaz, A; Margoni, M; Morandin, M; Pompili, A; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Voci, C; Benayoun, M; Briand, H; Chauveau, J; David, P; Buono, L Del; de la Vaissière, Ch; Hamon, O; Hartfiel, B L; Leruste, Ph; Malclès, J; Ocariz, J; Roos, L; Therin, G; Gladney, L; Biasini, M; Covarelli, R; Angelini, C; Batignani, G; Bettarini, S; Bucci, F; Calderini, G; Carpinelli, M; Cenci, R; Forti, F; Giorgi, M A; Lusiani, A; Marchiori, G; Mazur, M A; Morganti, M; Neri, N; Paoloni, E; Rizzo, G; Walsh, J J; Haire, M; Judd, D; Wagoner, D E; Biesiada, J; Danielson, N; Elmer, P; Lau, Y P; Lu, C; Olsen, J; Smith, A J S; Telnov, A V; Bellini, F; Cavoto, G; D'Orazio, A; del Re, D; Marco, E Di; Faccini, R; Ferrarotto, F; Ferroni, F; Gaspero, M; Gioi, L Li; Mazzoni, M A; Morganti, S; Piredda, G; Polci, F; Tehrani, F Safai; Voena, C; Ebert, M; Schröder, H; Waldi, R; Adye, T; Franek, B; Olaiya, E O; Ricciardi, S; Wilson, F F; Aleksan, R; Emery, S; Gaidot, A; Ganzhur, S F; de Monchenault, G Hamel; Kozanecki, W; Legendre, M; Vasseur, G; Yèche, Ch; Zito, M; Chen, X R; Liu, H; Park, W; Purohit, M V; Wilson, J R; Allen, M T; Aston, D; Bartoldus, R; Bechtle, P; Berger, N; Claus, R; Coleman, J P; Convery, M R; Dingfelder, J C; Dorfan, J; Dubois-Felsmann, G P; Dujmic, D; Dunwoodie, W; Field, R C; Glanzman, T; Gowdy, S J; Graham, M T; Grenier, P; Halyo, V; Hast, C; Hryn'ova, T; Innes, W R; Kelsey, M H; Kim, P; Leith, D W G S; Li, S; Luitz, S; Luth, V; Lynch, H L; Macfarlane, D B; Marsiske, H; Messner, R; Muller, D R; O'Grady, C P; Ozcan, V E; Perazzo, A; Perl, M; Pulliam, T; Ratcliff, B N; Roodman, A; Salnikov, A A; Schindler, R H; Schwiening, J; Snyder, A; Stelzer, J; Su, D; Sullivan, M K; Suzuki, K; Swain, S K; Thompson, J M; Va'vra, J; van Bakel, N; Wagner, A P; Weaver, M; Weinstein, A J R; Wisniewski, W J; Wittgen, M; Wright, D H; Wulsin, H W; Yarritu, A K; Yi, K; Young, C C; Burchat, P R; Edwards, A J; Majewski, S A; Petersen, B A; Wilden, L; Ahmed, S; Alam, M S; Bula, R; Ernst, J A; Jain, V; Pan, B; Saeed, M A; Wappler, F R; Zain, S B; Bugg, W; Krishnamurthy, M; Spanier, S M; Eckmann, R; Ritchie, J L; Satpathy, A; Schilling, C J; Schwitters, R F; Izen, J M; Lou, X C; Ye, S; Bianchi, F; Gallo, F; Gamba, D; Bomben, M; Bosisio, L; Cartaro, C; Cossutti, F; Ricca, G Della; Dittongo, S; Lanceri, L; Vitale, L; Azzolini, V; Lopez-March, N; Martinez-Vidal, F; Banerjee, Sw; Bhuyan, B; Brown, C M; Fortin, D; Hamano, K; Kowalewski, R; Nugent, I M; Roney, J M; Sobie, R J; Back, J J; Harrison, P F; Latham, T E; Mohanty, G B; Pappagallo, M; Band, H R; Chen, X; Cheng, B; Dasu, S; Datta, M; Flood, K T; Hollar, J J; Kutter, P E; Mellado, B; Mihalyi, A; Pan, Y; Pierini, M; Prepost, R; Wu, S L; Yu, Z; Neal, H

    2007-02-02

    We perform an amplitude analysis of the decays B(0)-->phiK*(2)(1430)(0), phiK*(892)(0), and phi(Kpi)(0)(S-wave) with a sample of about 384x10(6) BB[over ] pairs recorded with the BABAR detector. The fractions of longitudinal polarization f(L) of the vector-tensor and vector-vector decay modes are measured to be 0.853(-0.069+0.061)+/-0.036 and 0.506+/-0.040+/-0.015, respectively. Overall, twelve parameters are measured for the vector-vector decay and seven parameters for the vector-tensor decay, including the branching fractions and parameters sensitive to CP violation.

  14. Current progress of polymeric gene vectors

    Institute of Scientific and Technical Information of China (English)

    ZENG Xuan; SUN YunXia; ZHUO RenXi; ZHANG XianZheng

    2011-01-01

    After over 40 years ot progress,gene therapy provides great opportunities for treating diseases from various genetic disorders,infections and cancers.The success of gene therapy largely depends on the availability of suitable gene vectors.As an attractive alternative to virus-based gene therapy,non-viral gene delivery system has been developed and investigated due to their merits including low immunogenecity,convenient operability,and large-scale manufacturability [1].Because polycations can condense with DNA as a result of electrostatic interactions,form nanosize polyplexes,and protect DNA from degradation by DNase,cationic polymer becomes a major type of non-viral gene delivery vectors (Figure 1) [2].A wide range of polymeric vectors have been developed and investigated in the past decade,such as polyethylenimine (PEI)-based vectors,poly(L-lysine) (PLL)-based vectors,dendrimer-based vectors,polypeptide-based vectors,and chitosan-based vectors [3].However,unlike viral vectors that have the ability to infect host cells and overcome cellular barriers through the course of evolution,nonviral gene vectors exhibit Significantly reduced transfection efficiency as they are obstructed by various extra- and intracellular barriers,including serum proteins in blood stream,cell membrane,endosomal compartment and nuclear membrane [4].

  15. The silent role of AIF short hairpin RNA interference recombinant vector targeting neuroblastoma cells SHSY5Y%AIF靶向短发夹RNA干扰重组载体对神经母细胞瘤细胞SHSY5Y的沉默作用

    Institute of Scientific and Technical Information of China (English)

    王占强; 李叶丹; 李春宇; 张极星; 王全才; 贾春红; 张鸿

    2010-01-01

    目的 探讨AIF基因短发夹RNA(shRNA)表达质粒对神经母细胞瘤细胞(SHSY5YAIF)基因的干扰作用.方法 根据siRNA设计原则,构建靶向AIF基因的短发夹RNA干扰质粒(pGPU6/GFP/AIF),使用脂质体法转染人神经母细胞瘤细胞,通过RT-PCR和Wester blot印迹检测神经母细胞瘤细胞AIF基因mRNA和蛋白表达水平.结果 pGPU6/GFP/AIF重组质粒经限制性内切酶酶切及测序证明基因插入正确.质粒成功转染SHSY5Y细胞后,该细胞的AIFmRNA和蛋白表达明显下降(P<0.05).结论 成功构建靶向AIF基因的shRNA表达载体转染神经母细胞瘤细胞,有效抑制AIFmRNA和蛋白表达,为AIF基因靶向治疗提供前期的实验依据.

  16. Vector-Resonance-Multimode Instability

    Science.gov (United States)

    Sergeyev, S. V.; Kbashi, H.; Tarasov, N.; Loiko, Yu.; Kolpakov, S. A.

    2017-01-01

    The modulation and multimode instabilities are the main mechanisms which drive spontaneous spatial and temporal pattern formation in a vast number of nonlinear systems ranging from biology to laser physics. Using an Er-doped fiber laser as a test bed, here for the first time we demonstrate both experimentally and theoretically a new type of a low-threshold vector-resonance-multimode instability which inherits features of multimode and modulation instabilities. The same as for the multimode instability, a large number of longitudinal modes can be excited without mode synchronization. To enable modulation instability, we modulate the state of polarization of the lasing signal with the period of the beat length by an adjustment of the in-cavity birefringence and the state of polarization of the pump wave. As a result, we show the regime's tunability from complex oscillatory to periodic with longitudinal mode synchronization in the case of resonance matching between the beat and cavity lengths. Apart from the interest in laser physics for unlocking the tunability and stability of dynamic regimes, the proposed mechanism of the vector-resonance-multimode instability can be of fundamental interest for the nonlinear dynamics of various distributed systems.

  17. The vector BPS Skyrme model

    CERN Document Server

    Adam, C; Sanchez-Guillen, J; Wereszczynski, A

    2012-01-01

    We analyze the vector meson formulation of the BPS Skyrme model in (3+1) dimensions, where the term of sixth power in first derivatives characteristic for the original, integrable BPS Skyrme model (the topological or baryon current squared) is replaced by a coupling between the vector meson $\\omega_\\mu$ and the baryon current. We find that the model remains integrable in the sense of generalized integrability and almost solvable (reducible to a set of two first order ODEs) for any value of the baryon charge. Further, we analyze the appearance of topological solitons for two one-parameter families of one vacuum potentials: the old Skyrme potentials and the so-called BPS potentials. Depending on the value of the parameters we find several qualitatively different possibilities. In the massless case we have a parameter region with no skyrmions, a unique compact skyrmion with a discontinuous first derivative at the boundary (equivalently, with a source term located at the boundary, which screens the topological ch...

  18. Functional genomics studies on the innate immunity of disease vectors

    Institute of Scientific and Technical Information of China (English)

    Luke A. Baton; Lindsey Garver; Zhiyong Xi; George Dimopoulos

    2008-01-01

    The increasing availability of genome sequences and the development of high-throughput techniques for gene expression profiling and functional characterization are transforming the study of innate immunity and other areas of insect biology. Already,functional genomic approaches have enabled a quantum advance in the characterization of mosquito immune responses to malaria parasite infection, and similar high-throughput functional genomic studies of other vector-pathogen interactions can be expected in the near future. The application of microarray-based and other expression analyses provide genomewide transcriptional profiles that can be used to identify insect immune system components that are differentially regulated upon exposure to various classes of pathogens, including many important etiologic agents of human and animal diseases. The role of infection-responsive or other candidate immune genes identified through comparative genomic approaches can then be functionally characterized, either in vivo, for instance in adult mosquitoes, or in vitro using cell lines. In most insect vectors of human pathogens, germ-line transgenesis is still technically difficult and maintenance of multiple transgenic lines logistically demanding.Consequently, transient RNA interference (RNAi)-mediated gene-silencing has rapidly become the method of choice for functional characterization of candidate innate immune genes. The powerful combination of transcriptional profiling in conjunction with assays using RNAi to determine gene function, and identify regulatory pathways, together with downstream cell biological approaches to determine protein localization and interactions,will continue to provide novel insights into the role of insect innate immunity in a variety of vector-pathogen interactions. Here we review advances in functional genomics studies of innate immunity in the insect disease vectors, over the past decade, with a particular focus on the Anopheles mosquito and its

  19. P19 of Tomato Bushy Stunt Virus Suppresses RNA Silencing Induced by Short Hairpin RNA in Mammal Cells

    Institute of Scientific and Technical Information of China (English)

    Wei-xian CHEN; Juan CHEN; Zhen-zhen ZHANG; Ai-long HUANG

    2007-01-01

    To counteract the immune system in parasitic hosts, some viruses encode proteins to suppress the RNA interference (RNAi) effect. In this report, we established two RNAi systems to be easily observed with strong and obvious effect. The function of the P19 of tomato bushy stunt virus, which suppresses RNAi in mammal cells, was then studied using these two systems. Short hairpin RNAs targeting green fluorescence protein (pshRNA-GFP) and firefly luciferase (pshRNA-luc) were designed and inserted into a eukaryotic transcriptional vector pTZU6+1, respectively. The shRNA expressing vectors were co-transfected with plasmids containing the target gene with or without P19. The GFP expression level was assayed by fluorescence microscopy, Western blotting and RT-PCR. The luciferase expression level was analyzed by the dual-luciferase assay system. pshRNA designed in this study down-regulated the target gene specifically and efficiently, with a decrease of expression of both genes of about 70%, respectively. When P19 was introduced into the RNAi systems, the expression of both GFP and the luciferase were mostly recovered compared with the control groups. The RNAi systems of GFP and luciferase were constructed successfully, demonstrating that P19 of tomato bushy stunt virus has the ability to counteract the RNAi effect induced by shRNA in mammal cells.

  20. A Modified Moist Ageostrophic Q Vector

    Institute of Scientific and Technical Information of China (English)

    YUE Caijun; SHOU Shaowen

    2008-01-01

    The quasi-geostrophic Q vector is an important diagnostic tool for studying development of surface rainfall associated with large-scale weather systems and is calculated using data at single vertical level. When ageostrophic Q vector was introduced, it required data at two vertical levels. In this study, moist ageostrophic Q vector is modified so that it can be calculated using data at a single vertical level. The comparison study between the original and modified moist ageostrophic Q vectors is conducted using the data from 5 to 6 July 1991 during the torrential rainfall event associated with the Changjiang-Huaihe mei-yu front in China. The results reveal that divergences of original and modified moist ageostrophic Q vectors have similar horizontal distributions and their centers are almost located in the precipitation centers. This indicates that modified moist ageostrophic Q vector can be used to diagnose convective development with reasonable accuracy.

  1. Vector assembly of colloids on monolayer substrates

    Science.gov (United States)

    Jiang, Lingxiang; Yang, Shenyu; Tsang, Boyce; Tu, Mei; Granick, Steve

    2017-06-01

    The key to spontaneous and directed assembly is to encode the desired assembly information to building blocks in a programmable and efficient way. In computer graphics, raster graphics encodes images on a single-pixel level, conferring fine details at the expense of large file sizes, whereas vector graphics encrypts shape information into vectors that allow small file sizes and operational transformations. Here, we adapt this raster/vector concept to a 2D colloidal system and realize `vector assembly' by manipulating particles on a colloidal monolayer substrate with optical tweezers. In contrast to raster assembly that assigns optical tweezers to each particle, vector assembly requires a minimal number of optical tweezers that allow operations like chain elongation and shortening. This vector approach enables simple uniform particles to form a vast collection of colloidal arenes and colloidenes, the spontaneous dissociation of which is achieved with precision and stage-by-stage complexity by simply removing the optical tweezers.

  2. An efficient viral vector for functional genomic studies of Prunus fruit trees and its induced resistance to Plum pox virus via silencing of a host factor gene

    OpenAIRE

    Cui, Hongguang; Wang, Aiming

    2016-01-01

    Summary RNA silencing is a powerful technology for molecular characterization of gene functions in plants. A commonly used approach to the induction of RNA silencing is through genetic transformation. A potent alternative is to use a modified viral vector for virus?induced gene silencing (VIGS) to degrade RNA molecules sharing similar nucleotide sequence. Unfortunately, genomic studies in many allogamous woody perennials such as peach are severely hindered because they have a long juvenile pe...

  3. Integrated epidemiology for vector-borne zoonoses

    OpenAIRE

    2016-01-01

    The development and application of interventions for the control of vector-borne zoonoses requires broad understanding of epidemiological linkages between vector, animal infection and human infection. However, there are significant gaps in our understanding of these linkages and a lack of appropriate data poses a considerable barrier to addressing this issue. A move towards strengthened surveillance of vectors and disease in both animal and human hosts, in combination with linked human-animal...

  4. Higgs Decays and Brane Gravi-vectors

    OpenAIRE

    Clark, T. E.; Liu, B. Y.; Love, S. T.; Xiong, C.; ter Veldhuis, T.

    2008-01-01

    Higgs boson decays in flexible brane world models with stable, massive gravi-vectors are considered. Such vectors couple bilinearly to the Standard Model fields through either the Standard Model energy-momentum tensor, the weak hypercharge field strength or the Higgs scalar. The role of the coupling involving the extrinsic curvature is highlighted. It is found that within the presently allowed parameter space, the decay rate of the Higgs into two gravi-vectors (which would appear as an invisi...

  5. [Research progress on malaria vector control].

    Science.gov (United States)

    Zhu, Guo-Ding; Cao, Jun; Zhou, Hua-Yun; Gao, Qi

    2013-06-01

    Vector control plays a crucial role in the stages of malaria control and elimination. Currently, it mainly relies on the chemical control methods for adult mosquitoes in malaria endemic areas, however, it is undergoing the serious threat by insecticide resistance. In recent years, the transgenic technologies of malaria vectors have made a great progress in the laboratory. This paper reviews the challenges of the traditional methods and the rapid developed genetic modified technology in the application of vector control.

  6. iRNA-seq

    DEFF Research Database (Denmark)

    Madsen, Jesper Grud Skat; Schmidt, Søren Fisker; Larsen, Bjørk Ditlev;

    2015-01-01

    RNA-seq is a sensitive and accurate technique to compare steady-state levels of RNA between different cellular states. However, as it does not provide an account of transcriptional activity per se, other technologies are needed to more precisely determine acute transcriptional responses. Here, we...... have developed an easy, sensitive and accurate novel computational method, IRNA-SEQ: , for genome-wide assessment of transcriptional activity based on analysis of intron coverage from total RNA-seq data. Comparison of the results derived from iRNA-seq analyses with parallel results derived using...... current methods for genome-wide determination of transcriptional activity, i.e. global run-on (GRO)-seq and RNA polymerase II (RNAPII) ChIP-seq, demonstrate that iRNA-seq provides similar results in terms of number of regulated genes and their fold change. However, unlike the current methods that are all...

  7. Strategies and advances in nanomedicine for targeted siRNA delivery.

    Science.gov (United States)

    Nimesh, Surendra; Gupta, Nidhi; Chandra, Ramesh

    2011-06-01

    siRNA are a rapidly emerging class of new therapeutic molecules for the treatment of inherited and acquired diseases. However, poor cellular uptake and instability in physiological conditions limits its therapeutic potential, hence a need to develop a delivery system that can protect and efficiently transport siRNA to the target cells has arisen. Nanoparticles have been proposed as suitable delivery vectors with reduced cytotoxicity and enhanced efficacy. These delivery vectors form condensed complexes with siRNA which, in turn, provides protection to siRNA against enzymatic degradation and further leads to tissue and cellular targeting. Nanoparticles derived from polymers, such as chitosan and polyethylenimine have found numerous applications owing to ease of manipulation, high stability, low cost and high gene carrying capability. This article focuses on various aspects of nanomedicine based siRNA delivery with emphasis on targeted delivery to tumors.

  8. RNA interference-mediated gene silencing of vascular endothelial growth factor in colon cancer cells

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    AIM: To inhibit the expression of vascular endothelial growth factor (VEGF) in colon cancer cell line by RNA interference (RNAi). METHODS: Followed the service of E-RNAi, we designed and constructed two kinds of shRNA expression vectors aiming at the VEGF gene, then transfected them into colon cancer HT29 cells by lipofectamineTM 2000. The level of VEGF mRNA was investigated by RT-PCR and Northern blotting. The protein expression of VEGF was observed by immunofluoresence staining and Western blotting. RESULTS: We got two kinds of VEGF specific shRNA expression vectors which could efficiently inhibit the expression of VEGF in HT29 cells. RT-PCR, Northern blotting, immunofluoresence staining and Western blotting showed that inhibition rate for VEGF expression was up to 42%, 89%, 73% and 82%, respectively. CONCLUSION: The expression of VEGF can be inhibited by RNA interference in HT29 cells.

  9. Genetic manipulation of endosymbionts to control vector and vector borne diseases

    Directory of Open Access Journals (Sweden)

    Jay Prakash Gupta

    Full Text Available Vector borne diseases (VBD are on the rise because of failure of the existing methods of control of vector and vector borne diseases and the climate change. A steep rise of VBDs are due to several factors like selection of insecticide resistant vector population, drug resistant parasite population and lack of effective vaccines against the VBDs. Environmental pollution, public health hazard and insecticide resistant vector population indicate that the insecticides are no longer a sustainable control method of vector and vector-borne diseases. Amongst the various alternative control strategies, symbiont based approach utilizing endosymbionts of arthropod vectors could be explored to control the vector and vector borne diseases. The endosymbiont population of arthropod vectors could be exploited in different ways viz., as a chemotherapeutic target, vaccine target for the control of vectors. Expression of molecules with antiparasitic activity by genetically transformed symbiotic bacteria of disease-transmitting arthropods may serve as a powerful approach to control certain arthropod-borne diseases. Genetic transformation of symbiotic bacteria of the arthropod vector to alter the vector’s ability to transmit pathogen is an alternative means of blocking the transmission of VBDs. In Indian scenario, where dengue, chikungunya, malaria and filariosis are prevalent, paratransgenic based approach can be used effectively. [Vet World 2012; 5(9.000: 571-576

  10. Pro jective vector fields on Finsler manifolds

    Institute of Scientific and Technical Information of China (English)

    TIAN Huang-jia

    2014-01-01

    In this paper, we give the equation that characterizes projective vector fields on a Finsler manifold by the local coordinate. Moreover, we obtain a feature of the projective fields on the compact Finsler manifold with non-positive flag curvature and the non-existence of projective vector fields on the compact Finsler manifold with negative flag curvature. Furthermore, we deduce some expectable, but non-trivial relationships between geometric vector fields such as projective, affine, conformal, homothetic and Killing vector fields on a Finsler manifold.

  11. A New Incremental Support Vector Machine Algorithm

    Directory of Open Access Journals (Sweden)

    Wenjuan Zhao

    2012-10-01

    Full Text Available Support vector machine is a popular method in machine learning. Incremental support vector machine algorithm is ideal selection in the face of large learning data set. In this paper a new incremental support vector machine learning algorithm is proposed to improve efficiency of large scale data processing. The model of this incremental learning algorithm is similar to the standard support vector machine. The goal concept is updated by incremental learning. Each training procedure only includes new training data. The time complexity is independent of whole training set. Compared with the other incremental version, the training speed of this approach is improved and the change of hyperplane is reduced.

  12. Vector perturbations of galaxy number counts

    Science.gov (United States)

    Durrer, Ruth; Tansella, Vittorio

    2016-07-01

    We derive the contribution to relativistic galaxy number count fluctuations from vector and tensor perturbations within linear perturbation theory. Our result is consistent with the the relativistic corrections to number counts due to scalar perturbation, where the Bardeen potentials are replaced with line-of-sight projection of vector and tensor quantities. Since vector and tensor perturbations do not lead to density fluctuations the standard density term in the number counts is absent. We apply our results to vector perturbations which are induced from scalar perturbations at second order and give numerical estimates of their contributions to the power spectrum of relativistic galaxy number counts.

  13. Vector perturbations of galaxy number counts

    CERN Document Server

    Durrer, Ruth

    2016-01-01

    We derive the contribution to relativistic galaxy number count fluctuations from vector and tensor perturbations within linear perturbation theory. Our result is consistent with the the relativistic corrections to number counts due to scalar perturbation, where the Bardeen potentials are replaced with line-of-sight projection of vector and tensor quantities. Since vector and tensor perturbations do not lead to density fluctuations the standard density term in the number counts is absent. We apply our results to vector perturbations which are induced from scalar perturbations at second order and give numerical estimates of their contributions to the power spectrum of relativistic galaxy number counts.

  14. RNA-modifying enzymes.

    Science.gov (United States)

    Ferré-D'Amaré, Adrian R

    2003-02-01

    A bewildering number of post-transcriptional modifications are introduced into cellular RNAs by enzymes that are often conserved among archaea, bacteria and eukaryotes. The modifications range from those with well-understood functions, such as tRNA aminoacylation, to widespread but more mysterious ones, such as pseudouridylation. Recent structure determinations have included two types of RNA nucleobase modifying enzyme: pseudouridine synthases and tRNA guanine transglycosylases.

  15. APPLICATION OF BIOTECHNOLOGY TO THE STUDY OF FILARIAL PARASITES AND THEIR VECTORS

    Directory of Open Access Journals (Sweden)

    A. C. Vickery

    2012-09-01

    Full Text Available Over 200 species of filarial parasites have been described, although the life cycle and nature of their obligate intermediate arthropod vectors have been identified for only about a quarter of them. Traditional methods of studying phylogenetic relationships between closely related parasite species have utilized morphologic, biochemical and biologic characteristics, usually of the microfilarial stage. Identification of competent vectors from among complexes of sibling species, has employed similar techniques, despite the fact that differences between geographical isolates may reflect environmental rather than genetically controlled factors. Studies of the prevalence and transmission of animal, human and zoonotic filarids, so important for vector identification and control, has lead to the examination of filarial parasites at the genetic level. Genomic DNA libraries are being constructed and screened for clones which are species specific. From this work, DNA probes which can accurately enumerate larval stages in vector squash preparations, and monoclonal antibodies specific for defined filarial antigens, are being prepared. The nucleotide sequences of rRNA are also being defined. The application of these technologies to the study of filarial parasites and their vectors, promises to not only allow the construction of accurate phylogenetic trees, but also to provide the data necessary for the identification and control of the vectors of filarial pathogens of animals and man.

  16. Development of avian sarcoma and leukosis virus-based vector-packaging cell lines

    Energy Technology Data Exchange (ETDEWEB)

    Stoker, A.W.; Bissell, M.J. (Univ. of California, Berkeley (USA))

    1988-03-01

    The authors have constructed an avian leukosis virus derivative with a 5{prime} deletion extending from within the tRNA primer binding site to a SacI site in the leader region. The aim was to remove cis-acting replicative and/or encapsidation sequences and to use this derivative, RAV-1{Psi}{sup {minus}}, to develop vector-packaging cell lines. They show that RAV-1{Psi}{sup {minus}} can be stably expressed in the quail cell line QT6 and chicken embryo fibroblasts and that it is completely replication deficient in both cell types. Moreover, they have demonstrated that QT6-derived lines expressing RAV-1{Psi}{sup {minus}} can efficiently package four structurally different replication-defective v-src expression vectors into infectious virus, with very low or undetectable helper virus release. These RAV-{Psi}{sup {minus}}-expressing cell lines comprise the first prototype avian sarcoma and leukosis virus-based vector-packaging system. The construction of our vectors has also shown us that a sequence present within gag, thought to facilitate virus packaging, is not necessary for efficient vector expression and high virus production. They show that quantitation and characterization of replication-defective viruses can be achieved with a sensitive immunocytochemical procedure, presenting an alternative to internal selectable vector markers.

  17. APPLICATION OF BIOTECHNOLOGY TO THE STUDY OF FILARIAL PARASITES AND THEIR VECTORS

    Directory of Open Access Journals (Sweden)

    A. C. Vickery

    2012-09-01

    Full Text Available Over 200 species of filarial parasites have been described, although the life cycle and nature of their obligate intermediate arthropod vectors have been identified for only about a quarter of them. Traditional methods of studying phylogenetic relationships between closely related parasite species have utilized morphologic, biochemical and biologic characteristics, usually of the microfilarial stage. Identification of competent vectors from among complexes of sibling species, has employed similar techniques, despite the fact that differences between geographical isolates may reflect environmental rather than genetically controlled factors. Studies of the prevalence and transmission of animal, human and zoonotic filarids, so important for vector identification and control, has lead to the examination of filarial parasites at the genetic level. Genomic DNA libraries are being constructed and screened for clones which are species specific. From this work, DNA probes which can accurately enumerate larval stages in vector squash preparations, and monoclonal antibodies specific for defined filarial antigens, are being prepared. The nucleotide sequences of rRNA are also being defined. The application of these technologies to the study of filarial parasites and their vectors, promises to not only allow the construction of accurate phylogenetic trees, but also to provide the data necessary for the identification and control of the vectors of filarial pathogens of animals and man.

  18. Development and use of an efficient DNA-based viral gene silencing vector for soybean.

    Science.gov (United States)

    Zhang, Chunquan; Yang, Chunling; Whitham, Steven A; Hill, John H

    2009-02-01

    Virus-induced gene silencing (VIGS) is increasingly being used as a reverse genetics tool to study functions of specific plant genes. It is especially useful for plants, such as soybean, that are recalcitrant to transformation. Previously, Bean pod mottle virus (BPMV) was shown to be an effective VIGS vector for soybean. However, the reported BPMV vector requires in vitro RNA transcription and inoculation, which is not reliable or amenable to high-throughput applications. To increase the efficiency of the BPMV vector for soybean functional genomics, a DNA-based version was developed. Reported here is the construction of a Cauliflower mosaic virus 35S promoter-driven BPMV vector that is efficient for the study of soybean gene function. The selection of a mild rather than a severe BPMV strain greatly reduced the symptom interference caused by virus infection. The DNA-based BPMV vector was used to silence soybean homologues of genes involved in plant defense, translation, and the cytoskeleton in shoots and in roots. VIGS of the Actin gene resulted in reduced numbers of Soybean mosaic virus infection foci. The results demonstrate the utility of this new vector as an efficient tool for a wide range of applications for soybean functional genomics.

  19. Live-Attenuated Bacterial Vectors: Tools for Vaccine and Therapeutic Agent Delivery

    Directory of Open Access Journals (Sweden)

    Ivan Y. C. Lin

    2015-11-01

    Full Text Available Genetically attenuated microorganisms, including pathogenic and commensal bacteria, can be engineered to carry and deliver heterologous antigens to elicit host immunity against both the vector as well as the pathogen from which the donor gene is derived. These live attenuated bacterial vectors have been given much attention due to their capacity to induce a broad range of immune responses including localized mucosal, as well as systemic humoral and/or cell-mediated immunity. In addition, the unique tumor-homing characteristics of these bacterial vectors has also been exploited for alternative anti-tumor vaccines and therapies. In such approach, tumor-associated antigen, immunostimulatory molecules, anti-tumor drugs, or nucleotides (DNA or RNA are delivered. Different potential vectors are appropriate for specific applications, depending on their pathogenic routes. In this review, we survey and summarize the main features of the different types of live bacterial vectors and discussed the clinical applications in the field of vaccinology. In addition, different approaches for using live attenuated bacterial vectors for anti-cancer therapy is discussed, and some promising pre-clinical and clinical studies in this field are outlined.

  20. An elusive vector dark matter

    Directory of Open Access Journals (Sweden)

    Chuan-Ren Chen

    2015-02-01

    Full Text Available Even though the sensitivity of direct dark matter search experiments reaches the level of about 10−45 cm2, no confident signal of dark matter has been observed. We point out that, if dark matter is a vector boson, the null result in direct dark matter search experiments may be due to the destructive effects in dark-matter–nucleon elastic scattering. We illustrate the scenario using a modified Higgs portal model that includes exotic quarks. The significant cancellation can occur for a certain mass gap between new heavy quark and dark matter. As a result, the spin-independent dark-matter–nucleon elastic scattering is so suppressed that the future direct search experiments will hardly observe the signal of dark matter.