WorldWideScience

Sample records for baculovirus-infected insect cells

  1. A Mathematical Model of Baculovirus Infection on Insect Cells at Low Multiplicity of Infection

    Institute of Scientific and Technical Information of China (English)

    You-Hong ZHANG; Josée C. MERCHUK

    2004-01-01

    The expression efficiency of the insect cells-baculovirus system used for insecticidal virus production and the expression of medically useful foreign genes is closely related with the dynamics of infection. The present studies develop a model of the dynamic process of insect cell infection with baculovirus at low multiplicity of infection (MOI), which is based on the multi-infection cycles of insect cell infection at low MOI. A mathematical model for the amount of viruses released from primary infected cells and the amount of free viruses before secondary infected cells release viruses has been developed. Comparison of the simulation results with the experimental data confirms qualitatively that this model is highly reasonable before secondary infected cells release viruses. This model is considered as a base for further modeling the entire complicated infection process.

  2. Expression of bovine vitamin K-dependent carboxylase activity in baculovirus-infected insect cells.

    Science.gov (United States)

    Roth, D A; Rehemtulla, A; Kaufman, R J; Walsh, C T; Furie, B; Furie, B C

    1993-09-15

    A vitamin K-dependent carboxylase has recently been purified from bovine liver microsomes and candidate cDNA clones have been isolated. Definitive identification of the carboxylase remains circumstantial since expression of candidate carboxylase cDNAs in mammalian cells is confounded by the presence of endogenous carboxylase activity. To overcome this problem, a recombinant strain of baculovirus (Autographa california nuclear polyhedrosis virus, AcMNPV) encoding a putative carboxylase (vbCbx/AcMNPV) was used to infect Sf9 insect cells, which we demonstrate have no endogenous carboxylase activity. Infection with vbCbx/AcMNPV conferred vitamin K-dependent carboxylase activity to Sf9 insect cells. Carboxylase activity was demonstrated to peak 2-3 days after infection with vbCbx/AcMNPV. Metabolic radiolabeling with L-[35S]methionine revealed that the 90-kDa recombinant protein is the major protein synthesized at the time of peak activity after infection. An anti-peptide antibody directed against residues 86-99 reacted with bovine liver carboxylase on Western blot analysis and immunoprecipitated recombinant carboxylase from infected Sf9 microsomal protein preparations. Since Sf9 insect cells lack endogenous vitamin K-dependent carboxylase activity, expression of carboxylase activity in Sf9 insect cells with recombinant baculovirus demonstrates that the protein encoded by this cDNA is a vitamin K-dependent gamma-glutamyl carboxylase. PMID:8378308

  3. A new theraphosid spider toxin causes early insect cell death by necrosis when expressed in vitro during recombinant baculovirus infection.

    Directory of Open Access Journals (Sweden)

    Daniel Mendes Pereira Ardisson-Araújo

    Full Text Available Baculoviruses are the most studied insect viruses in the world and are used for biological control of agricultural and forest insect pests. They are also used as versatile vectors for expression of heterologous proteins. One of the major problems of their use as biopesticides is their slow speed to kill insects. Thus, to address this shortcoming, insect-specific neurotoxins from arachnids have been introduced into the baculovirus genome solely aiming to improve its virulence. In this work, an insecticide-like toxin gene was obtained from a cDNA derived from the venom glands of the theraphosid spider Brachypelma albiceps. The mature form of the peptide toxin (called Ba3 has a high content of basic amino acid residues, potential for three possible disulfide bonds, and a predicted three-stranded β-sheetDifferent constructions of the gene were engineered for recombinant baculovirus Autographa californica multiple nuclepolyhedrovirus (AcMNPV expression. Five different forms of Ba3 were assessed; (1 the full-length sequence, (2 the pro-peptide and mature region, (3 only the mature region, and the mature region fused to an (4 insect or a (5 virus-derived signal peptide were inserted separately into the genome of the baculovirus. All the recombinant viruses induced cell death by necrosis earlier in infection relative to a control virus lacking the toxin gene. However, the recombinant virus containing the mature portion of the toxin gene induced a faster cell death than the other recombinants. We found that the toxin construct with the signal peptide and/or pro-peptide regions delayed the necrosis phenotype. When infected cells were subjected to ultrastructural analysis, the cells showed loss of plasma membrane integrity and structural changes in mitochondria before death. Our results suggest this use of baculovirus is a potential tool to help understand or to identify the effect of insect-specific toxic peptides when produced during infection of insect

  4. A new theraphosid spider toxin causes early insect cell death by necrosis when expressed in vitro during recombinant baculovirus infection.

    Science.gov (United States)

    Ardisson-Araújo, Daniel Mendes Pereira; Morgado, Fabrício Da Silva; Schwartz, Elisabeth Ferroni; Corzo, Gerardo; Ribeiro, Bergmann Morais

    2013-01-01

    Baculoviruses are the most studied insect viruses in the world and are used for biological control of agricultural and forest insect pests. They are also used as versatile vectors for expression of heterologous proteins. One of the major problems of their use as biopesticides is their slow speed to kill insects. Thus, to address this shortcoming, insect-specific neurotoxins from arachnids have been introduced into the baculovirus genome solely aiming to improve its virulence. In this work, an insecticide-like toxin gene was obtained from a cDNA derived from the venom glands of the theraphosid spider Brachypelma albiceps. The mature form of the peptide toxin (called Ba3) has a high content of basic amino acid residues, potential for three possible disulfide bonds, and a predicted three-stranded β-sheetDifferent constructions of the gene were engineered for recombinant baculovirus Autographa californica multiple nuclepolyhedrovirus (AcMNPV) expression. Five different forms of Ba3 were assessed; (1) the full-length sequence, (2) the pro-peptide and mature region, (3) only the mature region, and the mature region fused to an (4) insect or a (5) virus-derived signal peptide were inserted separately into the genome of the baculovirus. All the recombinant viruses induced cell death by necrosis earlier in infection relative to a control virus lacking the toxin gene. However, the recombinant virus containing the mature portion of the toxin gene induced a faster cell death than the other recombinants. We found that the toxin construct with the signal peptide and/or pro-peptide regions delayed the necrosis phenotype. When infected cells were subjected to ultrastructural analysis, the cells showed loss of plasma membrane integrity and structural changes in mitochondria before death. Our results suggest this use of baculovirus is a potential tool to help understand or to identify the effect of insect-specific toxic peptides when produced during infection of insect cells. PMID

  5. Temporal expression of HIV-1 envelope proteins in baculovirus-infected insect cells: Implications for glycosylation and CD4 binding

    International Nuclear Information System (INIS)

    Three different human immunodeficiency virus type I (HIV-1) envelope derived recombinant proteins and the full length human CD4 polypeptide were expressed in Spodoptera frugiperda (Sf9) cells. DNA constructs encoding CD4, gp120, gp160, and gp160 delta were cloned into the baculovirus expression vector pVL941 or a derivative and used to generate recombinant viruses in a cotransfection with DNA from Autographa californica nuclear polyhedrosis virus (AcMNPV). Western blotting of cell extracts of the recombinant HIV-1 proteins showed that for each construct two major bands specifically reacted with anti-HIV-1 envelope antiserum. These bands corresponded to glycosylated and nonglycosylated versions of the HIV proteins as determined by 3H-mannose labeling and tunicamycin treatment of infected cells. A time course of HIV envelope expression revealed that at early times post-infection (24 hours) the proteins were fully glycosylated and soluble in nonionic detergents. However, at later times postinfection (48 hours), expression levels of recombinant protein reached a maximum but most of the increase was due to a rise in the level of the nonglycosylated species, which was largely insoluble in nonionic detergents. Thus, it appears that Sf9 cells cannot process large amounts of glycosylated recombinant proteins efficiently. As a measure of biological activity, the CD4 binding ability of both glycosylated and nonglycosylated recombinant HIV envelope proteins was tested in a coimmunoprecipitation assay. The results showed that CD4 and the glycosylated versions of recombinant gp120 or gp160 delta specifically associated with one another in this analysis. Nonglycosylated gp120 or gp160 delta proteins from tunicamycin-treated cultures did immunoprecipitate with anti-HIV-1 antiserum but did not interact with CD4

  6. Enhanced recombinant protein production and differential expression of molecular chaperones in sf-caspase-1-repressed stable cells after baculovirus infection

    Directory of Open Access Journals (Sweden)

    Lai Yiu-Kay

    2012-11-01

    Full Text Available Abstract Background There are few studies that have examined the potential of RNA inference (RNAi to increase protein production in the baculovirus expression vector system (BEVS. Spodoptera frugiperda (fall armyworm (Sf-caspase-1-repressed stable cells exhibit resistance to apoptosis and enhancement of recombinant protein production. However, the mechanism of recombinant protein augmentation in baculovirus-infected Caspase-repressed insect cells has not been elucidated. Results In the current study, we utilized RNAi-mediated Sf-caspase-1-repressed stable cells to clarify how the resistance to apoptosis can enhance both intracellular (firefly luciferase and extracellular (secreted alkaline phosphatase [SEAP] recombinant protein production in BEVS. Since the expression of molecular chaperones is strongly associated with the maximal production of exogenous proteins in BEVS, the differential expression of molecular chaperones in baculovirus-infected stable cells was also analyzed in this study. Conclusion The data indicated that the retention of expression of molecular chaperones in baculovirus-infected Sf-caspase-1-repressed stable cells give the higher recombinant protein accumulation.

  7. Efficient, low-cost protein factories: expression of human adenosine deaminase in baculovirus-infected insect larvae.

    OpenAIRE

    Medin, J A; Hunt, L; Gathy, K; Evans, R K; Coleman, M S

    1990-01-01

    Human adenosine deaminase (EC 3.5.4.4), a key purine salvage enzyme essential for immune competence, has been overproduced in Spodoptera frugiperda cells and in Trichoplusia ni (cabbage looper) larvae infected with recombinant baculovirus. The coding sequence of human adenosine deaminase was recombined into a baculovirus immediately downstream from the strong polyhedrin gene promoter. Approximately 60 hr after infection of insect cells with the recombinant virus, maximal levels of intracellul...

  8. Spontaneous excision of BAC vector sequences from bacmid-derived baculovirus expression vectors upon passage in insect cells

    NARCIS (Netherlands)

    Pijlman, G.P.; Schijndel, van J.; Vlak, J.M.

    2003-01-01

    Repeated baculovirus infections in cultured insect cells lead to the generation of defective interfering viruses (DIs), which accumulate at the expense of the intact helper virus and compromise heterologous protein expression. In particular, Autographa californica multicapsid nucleopolyhedovirus (Ac

  9. Baculovirus infection of nondividing mammalian cells: mechanisms of entry and nuclear transport of capsids.

    NARCIS (Netherlands)

    N.D. van Loo; E. Fortunati (Elisabetta); E.M.E. Ehlert (Ehrich); M. Rabelink; F.G. Grosveld (Frank); B.J. Scholte (Bob)

    2001-01-01

    textabstractWe have studied the infection pathway of Autographa californica multinuclear polyhedrosis virus (baculovirus) in mammalian cells. By titration with a baculovirus containing a green fluorescent protein cassette, we found that several, but not all, mammalian c

  10. Enhanced expression of full-length human cytomegalovirus fusion protein in non-swelling baculovirus-infected cells with a minimal fed-batch strategy.

    Directory of Open Access Journals (Sweden)

    Marco Patrone

    Full Text Available Human cytomegalovirus congenital infection represents an unmet medical issue and attempts are ongoing to develop an effective vaccine. The virion fusion players of this enveloped virus are the natural targets to achieve this goal and to develop novel anti-viral therapies. The secreted ectodomain of the viral fusion factor glycoprotein B (gB has been exploited so far as an alternative to the cumbersome expression of the wild type trans-membrane protein. In the soluble form, gB showed encouraging but limited potential as antigen candidate calling for further efforts. Here, the exhaustive evaluation of the Baculovirus/insect cell expression system has been coupled to an orthogonal screening for expression additives to produce full-length gB. In detail, rapamycin was found to prolong gB intracellular accumulation while inhibiting the infection-induced cell swelling. Not obvious to predict, this inhibition did not affect Baculovirus growth, revealing that the virus-induced cell size increase is a dispensable side phenotype. In parallel, a feeding strategy for the limiting nutrient cysteine has been set up which improved gB stability. This multi-modal scheme allowed the production of full-length, mutation-free gB in the milligram scale. The recombinant full-length gB obtained was embedded into a stable mono-dispersed particle substantially larger than the protein trimer itself, according to the reported association of this protein with detergent-resistant lipid domains.

  11. Expression of the human interleukin-2 receptor gamma chain in insect cells using a baculovirus expression vector.

    Science.gov (United States)

    Raivio, E; Oetken, C; Oker-Blom, C; Engberg, C; Akerman, K; Lindqvist, C

    1995-04-01

    The gene encoding the gamma-chain of the human Interleukin-2 receptor was expressed in lepidopteran insect cells using the baculovirus expression vector system. The corresponding gene was inserted under the polyhedrin promoter of the Autographa californica nuclear polyhedrosis virus and expressed in the Spodoptera frugiperda insect cell line Sf9 during viral infection. The recombinant receptor protein was identified by immunoblotting in cell lysates, prepared from insect cells infected with the recombinant virus. At 40 h post infection the corresponding protein was detected as two major bands with apparent molecular weights of 50-60 kDa using a rabbit anti-human IL-2R gamma-receptor specific antiserum. Metabolic labelling with [35S]-methionine and SDS-PAGE analysis of the recombinant baculovirus infected insect cells verified the immunoblotting data. The expressed IL-2R gamma- protein could also be determined on the surface of infected insect cells by flow cytometer analysis. PMID:7899821

  12. Characterization of an Sf-rhabdovirus-negative Spodoptera frugiperda cell line as an alternative host for recombinant protein production in the baculovirus-insect cell system.

    Science.gov (United States)

    Maghodia, Ajay B; Geisler, Christoph; Jarvis, Donald L

    2016-06-01

    Cell lines derived from the fall armyworm, Spodoptera frugiperda (Sf), are widely used as hosts for recombinant protein production in the baculovirus-insect cell system (BICS). However, it was recently discovered that these cell lines are contaminated with a virus, now known as Sf-rhabdovirus [1]. The detection of this adventitious agent raised a potential safety issue that could adversely impact the BICS as a commercial recombinant protein production platform. Thus, we examined the properties of Sf-RVN, an Sf-rhabdovirus-negative Sf cell line, as a potential alternative host. Nested RT-PCR assays showed Sf-RVN cells had no detectable Sf-rhabdovirus over the course of 60 passages in continuous culture. The general properties of Sf-RVN cells, including their average growth rates, diameters, morphologies, and viabilities after baculovirus infection, were virtually identical to those of Sf9 cells. Baculovirus-infected Sf-RVN and Sf9 cells produced equivalent levels of three recombinant proteins, including an intracellular prokaryotic protein and two secreted eukaryotic glycoproteins, and provided similar N-glycosylation patterns. In fact, except for the absence of Sf-rhabdovirus, the only difference between Sf-RVN and Sf9 cells was SF-RVN produced higher levels of infectious baculovirus progeny. These results show Sf-RVN cells can be used as improved, alternative hosts to circumvent the potential safety hazard associated with the use of Sf-rhabdovirus-contaminated Sf cells for recombinant protein manufacturing with the BICS.

  13. Establishment of a highly efficient virus-inducible CRISPR/Cas9 system in insect cells.

    Science.gov (United States)

    Dong, Zhan-Qi; Chen, Ting-Ting; Zhang, Jun; Hu, Nan; Cao, Ming-Ya; Dong, Fei-Fan; Jiang, Ya-Ming; Chen, Peng; Lu, Cheng; Pan, Min-Hui

    2016-06-01

    Although current antiviral strategies can inhibit baculovirus infection and decrease viral DNA replication to a certain extent, novel tools are required for specific and accurate elimination of baculovirus genomes from infected insects. Using the newly developed clustered regularly interspaced short palindromic repeats/associated protein 9 nuclease (CRISPR/Cas9) technology, we disrupted a viral genome in infected insect cells in vitro as a defense against viral infection. We optimized the CRISPR/Cas9 system to edit foreign and viral genome in insect cells. Using Bombyx mori nucleopolyhedrovirus (BmNPV) as a model, we found that the CRISPR/Cas9 system was capable of cleaving the replication key factor ie-1 in BmNPV thus effectively inhibiting virus proliferation. Furthermore, we constructed a virus-inducible CRISPR/Cas9 editing system, which minimized the probability of off-target effects and was rapidly activated after viral infection. This is the first report describing the application of the CRISPR/Cas9 system in insect antiviral research. Establishment of a highly efficient virus-inducible CRISPR/Cas9 system in insect cells provides insights to produce virus-resistant transgenic strains for future. PMID:26979473

  14. Establishment of a highly efficient virus-inducible CRISPR/Cas9 system in insect cells.

    Science.gov (United States)

    Dong, Zhan-Qi; Chen, Ting-Ting; Zhang, Jun; Hu, Nan; Cao, Ming-Ya; Dong, Fei-Fan; Jiang, Ya-Ming; Chen, Peng; Lu, Cheng; Pan, Min-Hui

    2016-06-01

    Although current antiviral strategies can inhibit baculovirus infection and decrease viral DNA replication to a certain extent, novel tools are required for specific and accurate elimination of baculovirus genomes from infected insects. Using the newly developed clustered regularly interspaced short palindromic repeats/associated protein 9 nuclease (CRISPR/Cas9) technology, we disrupted a viral genome in infected insect cells in vitro as a defense against viral infection. We optimized the CRISPR/Cas9 system to edit foreign and viral genome in insect cells. Using Bombyx mori nucleopolyhedrovirus (BmNPV) as a model, we found that the CRISPR/Cas9 system was capable of cleaving the replication key factor ie-1 in BmNPV thus effectively inhibiting virus proliferation. Furthermore, we constructed a virus-inducible CRISPR/Cas9 editing system, which minimized the probability of off-target effects and was rapidly activated after viral infection. This is the first report describing the application of the CRISPR/Cas9 system in insect antiviral research. Establishment of a highly efficient virus-inducible CRISPR/Cas9 system in insect cells provides insights to produce virus-resistant transgenic strains for future.

  15. Ebola virus-like particles produced in insect cells exhibit dendritic cell stimulating activity and induce neutralizing antibodies

    International Nuclear Information System (INIS)

    Recombinant baculoviruses (rBV) expressing Ebola virus VP40 (rBV-VP40) or GP (rBV-GP) proteins were generated. Infection of Sf9 insect cells by rBV-VP40 led to assembly and budding of filamentous particles from the cell surface as shown by electron microscopy. Ebola virus-like particles (VLPs) were produced by coinfection of Sf9 cells with rBV-VP40 and rBV-GP, and incorporation of Ebola GP into VLPs was demonstrated by SDS-PAGE and Western blot analysis. Recombinant baculovirus infection of insect cells yielded high levels of VLPs, which were shown to stimulate cytokine secretion from human dendritic cells similar to VLPs produced in mammalian cells. The immunogenicity of Ebola VLPs produced in insect cells was evaluated by immunization of mice. Analysis of antibody responses showed that most of the GP-specific antibodies were of the IgG2a subtype, while no significant level of IgG1 subtype antibodies specific for GP was induced, indicating the induction of a Th1-biased immune response. Furthermore, sera from Ebola VLP immunized mice were able to block infection by Ebola GP pseudotyped HIV virus in a single round infection assay, indicating that a neutralizing antibody against the Ebola GP protein was induced. These results show that production of Ebola VLPs in insect cells using recombinant baculoviruses represents a promising approach for vaccine development against Ebola virus infection

  16. Expression of the mouse interleukin-2 receptor gamma chain in insect cells using a baculovirus expression vector--comparison with the human common gamma chain.

    Science.gov (United States)

    Stenroos, K; West, A; Raivio, E; Lindqvist, C

    1997-02-01

    The gene encoding the gamma-chain of the mouse Interleukin-2 receptor was expressed in lepidopteran insect cells using the baculovirus expression vector system. The corresponding gene was inserted under the polyhedrin promoter of the Autographa californica nuclear polyhedrosis virus and expressed in the Spodoptera frugiperda insect cell line Sf9 during viral infection. The recombinant receptor protein was identified by immunoblotting in cell lysates prepared from insect cells infected with the produced recombinant virus VL1392-mIL-2R gamma. Kinetic analysis demonstrated that the corresponding protein could be detected as an approximately 50 kDa protein already at 24 h post-infection. Intrinsic labelling with [35S]-methionine/cysteine and SDS-PAGE analysis of the recombinant baculovirus infected insect cells verified the immunoblotting data. The expressed IL-2R gamma protein could also be determined on the surface of infected insect cells by flow cytometric analysis. Comparison of the molecular weights between baculovirus expressed human and mouse IL-2R gamma chains indicated differences in the glycosylation pattern despite similar numbers of N-linked glycosylation sites. PMID:9042425

  17. Human μ—opioid receptor overexpressed in Sf9 insect cells functionally coupled to endogenous Gi/0 proteins

    Institute of Scientific and Technical Information of China (English)

    WEIQIANG; QINGXIANGSHEN; 等

    2000-01-01

    Human μ-opioid receptor(HμOR) with a tag of six consecutive histidines at its carboxyl terminus has been expressed in recombinant baculovirus infected Sf9 insect cells.The maximal binding capacity for the [3H] diprenorphine and [3H] ohmefentanyl (Ohm) were 9.1±0.7 and 6.52±0.23 nmol/g protein,respectively.The [3H] diprenorphine or [3H] Ohm binding to the receptor expressed in Sf9 cells was strongly inhibited by μ-selective agonists [D-Ala2,N-methyl-Phe4,glyol5] enkephalin(DAGO),Ohm,and morphine,but neither by δ nor by κ selective agonist.Na+ (100mM) and GTP(50μM) could reduce HμOR agonists etorphine and Ohm affinity binding to the overexpressed HμOR.μ-selective agonists DAGO and Ohm effectively stimulated [35S]GTP γS binding (EC50=2.7nM and 6.9 nM)and inhibited forskolin-stimulated cAMP accumulation(IC50=0.9 nM and 0.3 nM).The agonist-dependent effects could be blocked by opioid antagonist naloxone or by pretreatment of cells with pertussis toxin (PTX).These results demonstrated that HμOR overexpressed in Sf9 insect cells functionally coupled to endogenous Ci/o proteins.

  18. Insect Cell Culture and Biotechnology

    Institute of Scientific and Technical Information of China (English)

    Robert R.Granados; Guoxun Li; G.W.Blissard

    2007-01-01

    The continued development of new cell culture technology is essential for the future growth and application of insect cell and baculovirus biotechnology. The use of cell lines for academic research and for commercial applications is currently dominated by two cell lines; the Spodoptera frugiperda line, SF21 (and its clonal isolate, SF9), and the Trichoplusia ni line, BTI 5B1-4, commercially known as High Five cells. The long perceived prediction that the immense potential application of the baculovirus-insect cell system, as a tool in cell and molecular biology, agriculture, and animal health, has been achieved. The versatility and recent applications of this popular expression system has been demonstrated by both academia and industry and it is clear that this cell-based system has been widely accepted for biotechnological applications. Numerous small to midsize startup biotechnology companies in North America and the Europe are currently using the baculovirus-insect cell technology to produce custom recombinant proteins for research and commercial applications. The recent breakthroughs using the baculovirus-insect cell-based system for the development of several commercial products that will impact animal and human health will further enhance interest in this technology by pharma. Clearly, future progress in novel cell and engineering advances will lead to fundamental scientific discoveries and serve to enhance the utility and applications of this baculovirus-insect cell system.

  19. An economic approach to efficient isotope labeling in insect cells using homemade 15N-, 13C- and 2H-labeled yeast extracts

    International Nuclear Information System (INIS)

    Heterologous expression of proteins in insect cells is frequently used for crystallographic structural studies due to the high yields even for challenging proteins requiring the eukaryotic protein processing capabilities of the host. However for NMR studies, the need for isotope labeling poses extreme challenges in eukaryotic hosts. Here, we describe a robust method to achieve uniform protein 15N and 13C labeling of up to 90 % in baculovirus-infected insect cells. The approach is based on the production of labeled yeast extract, which is subsequently supplemented to insect cell growth media. The method also allows deuteration at levels of >60 % without decrease in expression yield. The economic implementation of the labeling procedures into a standard structural biology laboratory environment is described in a step-by-step protocol. Applications are demonstrated for a variety of NMR experiments using the Abelson kinase domain, GFP, and the beta-1 adrenergic receptor as examples. Deuterated expression of the latter provides spectra of very high quality of a eukaryotic G-protein coupled receptor

  20. An economic approach to efficient isotope labeling in insect cells using homemade {sup 15}N-, {sup 13}C- and {sup 2}H-labeled yeast extracts

    Energy Technology Data Exchange (ETDEWEB)

    Opitz, Christian; Isogai, Shin; Grzesiek, Stephan, E-mail: Stephan.Grzesiek@unibas.ch [University of Basel, Focal Area Structural Biology and Biophysics, Biozentrum (Switzerland)

    2015-07-15

    Heterologous expression of proteins in insect cells is frequently used for crystallographic structural studies due to the high yields even for challenging proteins requiring the eukaryotic protein processing capabilities of the host. However for NMR studies, the need for isotope labeling poses extreme challenges in eukaryotic hosts. Here, we describe a robust method to achieve uniform protein {sup 15}N and {sup 13}C labeling of up to 90 % in baculovirus-infected insect cells. The approach is based on the production of labeled yeast extract, which is subsequently supplemented to insect cell growth media. The method also allows deuteration at levels of >60 % without decrease in expression yield. The economic implementation of the labeling procedures into a standard structural biology laboratory environment is described in a step-by-step protocol. Applications are demonstrated for a variety of NMR experiments using the Abelson kinase domain, GFP, and the beta-1 adrenergic receptor as examples. Deuterated expression of the latter provides spectra of very high quality of a eukaryotic G-protein coupled receptor.

  1. An economic approach to efficient isotope labeling in insect cells using homemade 15N-, 13C- and 2H-labeled yeast extracts.

    Science.gov (United States)

    Opitz, Christian; Isogai, Shin; Grzesiek, Stephan

    2015-07-01

    Heterologous expression of proteins in insect cells is frequently used for crystallographic structural studies due to the high yields even for challenging proteins requiring the eukaryotic protein processing capabilities of the host. However for NMR studies, the need for isotope labeling poses extreme challenges in eukaryotic hosts. Here, we describe a robust method to achieve uniform protein (15)N and (13)C labeling of up to 90 % in baculovirus-infected insect cells. The approach is based on the production of labeled yeast extract, which is subsequently supplemented to insect cell growth media. The method also allows deuteration at levels of >60 % without decrease in expression yield. The economic implementation of the labeling procedures into a standard structural biology laboratory environment is described in a step-by-step protocol. Applications are demonstrated for a variety of NMR experiments using the Abelson kinase domain, GFP, and the beta-1 adrenergic receptor as examples. Deuterated expression of the latter provides spectra of very high quality of a eukaryotic G-protein coupled receptor. PMID:26070442

  2. Overcoming inefficient secretion of recombinant VEGF-C in baculovirus expression vector system by simple purification of the protein from cell lysate.

    Science.gov (United States)

    Klaus, Tomasz; Kulesza, Małgorzata; Bzowska, Monika; Wyroba, Barbara; Kilarski, Witold W; Bereta, Joanna

    2015-06-01

    The first reports about successfully expressed recombinant proteins with the use of a baculovirus vector were published over 30years ago. Despite the long time of refining this expression system, early problems with the production of baculovirus-derived secretory proteins are still not satisfactorily solved. The high expression level driven by baculoviral promoters often does not result in the desired yield of secreted recombinant proteins, which frequently accumulate inside insect cells and are only partially processed. During our attempts to produce vascular endothelial growth factor C (VEGF-C) with the use of a baculovirus vector we also faced an inefficient secretion of the recombinant protein to culture medium. We were not able to improve the outcome and obtain an acceptable concentration of VEGF-C in the medium by changing the culture conditions or utilizing different signal peptides. However, as a significant amount of native VEGF-C was detected inside the baculovirus-infected cells, we developed a simple method to purify recombinant, glycosylated VEGF-C from a lysate of the cells. The presented results indicate that the lack of a secretory protein in the insect cell culture medium after baculovirus infection does not necessarily signify failure in the production of the protein. As demonstrated by us and contrary to generally accepted views, the lysate of baculovirus-infected cells may constitute a valuable source of the biologically active, secretory protein.

  3. Human μ-opioid receptor overexpressed in Sf9 insect cells functionally coupled to endogenous Gi/o proteins

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Human μ-opioid receptor (HμOR) with a tag of six consecutive histidines at its carboxyl terminus had been expressed in recombinant baculovirus infected Sf9 insect cells.The maximal binding capacity for the [3H] diprenorphine and [3H]ohmefentanyl (Ohm) were 9.1 ± 0.7 and 6.52 ±0.23 nmol/g protein, respectively. The [3H] diprenorphine or [3H] Ohm binding to the receptor expressed in Sf9 cells was strongly inhibited by μ-selective agonists [D-Ala2, N-methyl-Phe4, glyol5]enkephalin (DAGO), Ohm, and morphine, but neither by δ nor by κ selective agonist. Na+ (100 mM) and GTP (50μM) could reduce HμOR agonists etorphine and Ohm affinity binding to the overexpressed HμOR.μ-selective agonists DAGO and Ohm effectively stimulated [35S]GTPγS binding (EC50 = 2.7nM and 6.9 nM) and inhibited forskolin- stimulated cAMP accumulation (IC50 = 0.9 nM and 0.3 nM). The agonist-dependent effects could be blocked by opioid antagonist naloxone or by pretreatment of cells with pertussis toxin (PTX). These results demonstrated that HμOR overexpressed in Sf9 insect cells functionally coupled to endogenous Gi/o proteins.Key words: Human μ-opioid receptor (Hμ OR), Sf9 insect cells, pertussis toxin (PTX), endogenous Gi/o proteins.

  4. Baculovirus Coinfection Strategy for Improved Galactosylation of Recombinant Glycoprotein Produced by Insect Cell Culture

    Science.gov (United States)

    Ney, Yap Wei; Rahman, Badarulhisam Abdul; Aziz, Azila Abdul

    Baculovirus Expression Vector System (BEVS) is widely used for the production of recombinant glycoproteins, but it is not ideal for pharmaceutical glycoprotein production due to incomplete glycosylation. The factors that ensure successful glycosylation are the presence of sufficient amount of glycosyltransferases, sugar nucleotides as the substrate donor and the recombinant protein as the substrate acceptor. In this study, we analyzed the galactosylation process by the introduction of ß-1,4galactosyltransferase (ß-1,4GalT) as the glycosyltransferase of interest and uridine-5`-diphosphogalactose (UDP-Gal) as the substrate donor. Recombinant human transferrin (rhTf) as a model protein was used as the substrate acceptor. Insect cell lines have been reported to produce a small amount of ß-1,4GalT and thus insufficient for effective galactosylation. In this study, we developed a method to produce galactosylated rhTf and optimized the expression of rhTf with better N-glycan quality. Recombinant ß-1,4GalT was introduced during protein expression by the coinfection of the BEVS with baculovirus carrying bovine ß-1,4GalT. To evaluate the extent of galactosylation by the coinfection strategy, a binding assay was established. In this binding assay, glycoprotein acceptor was absorbed onto ELISA plate surface. A lectin known as Ricinus communis agglutinin-I (RCA-I) labeled with peroxidase, was added and allowed to recognize Gal ß1>4GlcNAc group on the N-glycan of the glycoprotein, followed by appropriate color reaction measurements. Coexpression between rhTf and ß-1,4GalT did not show encouraging results due to the reduction of UDP-Gal upon baculovirus infection. This interesting finding suggested that the introduction of ß-1,4GalT alone was not sufficient for successful galactosylation. Alternatively, post harvest glycosylation method strategy seems to be a promising technique in the improvement of glycoprotein quality.

  5. Methods for Maintaining Insect Cell Cultures

    OpenAIRE

    Lynn, Dwight E.

    2002-01-01

    Insect cell cultures are now commonly used in insect physiology, developmental biology, pathology, and molecular biology. As the field has advanced from methods development to a standard procedure, so has the diversity of scientists using the technique. This paper describes methods that are effective for maintaining various insect cell lines. The procedures are differentiated between loosely or non-attached cell strains, attached cell strains, and strongly adherent cell strains.

  6. A ~35 kDa polypeptide from insect cells binds to yeast ACS like elements in the presence of ATP

    Directory of Open Access Journals (Sweden)

    Soni Rajesh K

    2002-08-01

    Full Text Available Abstract Background The S. cerevisiae origin recognition complex binds to the ARS consensus sequence in an ATP dependent fashion. Recently, the yeast Cdc6 has been reported to have DNA binding activity. Conservation of replication proteins among different species strongly supports their functional similarity. Here we report the results of an investigation into the DNA binding activity of human Cdc6 protein. Cdc6 was expressed and purified from baculovirus infected Sf9 (Spodoptera frugiperda insect cells as GST fusion protein (GST-Cdc6 and its DNA binding activity was tested. Results Partially purified fractions containing GSTCdc6 or GST showed an ACS binding activity in an ATP dependent manner. However, further purification revealed the presence of a putative 35 kDa insect cell protein (p35 which was found responsible for the DNA binding activity. A close match to the 9/11 bases of the ARS consensus sequence was sufficient for p35 binding activity. A DNA fragment from the human c-myc origin region containing yeast ACS like elements also showed p35 binding activity. Conclusions We have identified a Spodoptera frugiperda protein with ATP dependent DNA binding activity to ACS like elements. ACS like elements have been reported to be essential for ORC binding and replication initiation in yeast but their role in higher eukaryotes still remains elusive. Like the ARS consensus sequence elements of yeast, ACS like elements found in c-myc and lamin beta 2 origin regions may play similar roles in replication and indicate a conserved role for this DNA motif among eukaryotes.

  7. Internal ribosome entry site of Rhopalosiphum padi virus is functional in mammalian cells and has cryptic promoter activity in baculovirus-in fected Sf21 cells

    Institute of Scientific and Technical Information of China (English)

    Yi-jane WU; Chao-yi TENG; Yu-jie CHEN; Seng-chi CHEN; Ying-ju CHEN; Yi-ting LIN; Tzong-yuan WU

    2008-01-01

    Aim: To substantiate the in vitro translational studies of a cross-kingdom, inter- nal ribosome entry site (IRES), the 5"untranslated region of the Rhopalosiphum padi virus (RhPV), can function in mammalian cells and act as a shuttle IRES between insect cells and mammalian cells. Methods: Cytomegalovirus (CMV) promoter-based bicistronic mammalian cell expression vectors, either in plasmids or baculovirus vectors, were generated. Plasmid transient transfection and baculovirus transduction assays were performed to test whether the RhPV IRES can mediate translation activity in versatile mammalian cell lines. Results: Both plasmids and recombinant baculoviruses containing the CMV promoter and the RhPV IRES can mediate bicistronic gene expression in mammalian cells. However, in the CMV promoter containing recombinant baculovirus-infected insect Sf21 cells, only the second cistron gene expression was observed. Northern blot analysis and a promoterless assay demonstrated that the RhPV IRES exhibited cryptic promoter activity in baculovirus-infected insect cells. Conclusion: RhPV IRES can mediate gene expression in both insect cells and mammalian cells, and this characteristic of the RhPV IRES will facilitate the development of a bicistronic baculovirus gene therapy vectors.

  8. Insect cells for human food

    NARCIS (Netherlands)

    Verkerk, M.C.; Tramper, J.; Trijp, van J.C.M.; Martens, D.E.

    2007-01-01

    There is a need for novel protein sources. Insects are a possible interesting source of protein. They are nutritious in terms of protein (40-75 g/100g dry weight) and minerals. Insect protein is of high quality and has a high digestibility (77-98%) and concentration of essential amino acids (46-96%

  9. Insect biofuel cells using trehalose included in insect hemolymph leading to an insect-mountable biofuel cell.

    Science.gov (United States)

    Shoji, Kan; Akiyama, Yoshitake; Suzuki, Masato; Hoshino, Takayuki; Nakamura, Nobuhumi; Ohno, Hiroyuki; Morishima, Keisuke

    2012-12-01

    In this paper, an insect biofuel cell (BFC) using trehalose included in insect hemolymph was developed. The insect BFC is based on trehalase and glucose oxidase (GOD) reaction systems which oxidize β-glucose obtained by hydrolyzing trehalose. First, we confirmed by LC-MS that a sufficient amount of trehalose was present in the cockroach hemolymph (CHL). The maximum power density obtained using the insect BFC was 6.07 μW/cm(2). The power output was kept more than 10 % for 2.5 h by protecting the electrodes with a dialysis membrane. Furthermore, the maximum power density was increased to 10.5 μW/cm(2) by using an air diffusion cathode. Finally, we succeeded in driving a melody integrated circuit (IC) and a piezo speaker by connecting five insect BFCs in series. The results indicate that the insect BFC is a promising insect-mountable battery to power environmental monitoring micro-tools.

  10. Genome Scale Transcriptomics of Baculovirus-Insect Interactions

    Directory of Open Access Journals (Sweden)

    Steven Reid

    2013-11-01

    Full Text Available Baculovirus-insect cell technologies are applied in the production of complex proteins, veterinary and human vaccines, gene delivery vectors‚ and biopesticides. Better understanding of how baculoviruses and insect cells interact would facilitate baculovirus-based production. While complete genomic sequences are available for over 58 baculovirus species, little insect genomic information is known. The release of the Bombyx mori and Plutella xylostella genomes, the accumulation of EST sequences for several Lepidopteran species, and especially the availability of two genome-scale analysis tools, namely oligonucleotide microarrays and next generation sequencing (NGS, have facilitated expression studies to generate a rich picture of insect gene responses to baculovirus infections. This review presents current knowledge on the interaction dynamics of the baculovirus-insect system‚ which is relatively well studied in relation to nucleocapsid transportation, apoptosis, and heat shock responses, but is still poorly understood regarding responses involved in pro-survival pathways, DNA damage pathways, protein degradation, translation, signaling pathways, RNAi pathways, and importantly metabolic pathways for energy, nucleotide and amino acid production. We discuss how the two genome-scale transcriptomic tools can be applied for studying such pathways and suggest that proteomics and metabolomics can produce complementary findings to transcriptomic studies.

  11. Genome scale transcriptomics of baculovirus-insect interactions.

    Science.gov (United States)

    Nguyen, Quan; Nielsen, Lars K; Reid, Steven

    2013-11-01

    Baculovirus-insect cell technologies are applied in the production of complex proteins, veterinary and human vaccines, gene delivery vectors' and biopesticides. Better understanding of how baculoviruses and insect cells interact would facilitate baculovirus-based production. While complete genomic sequences are available for over 58 baculovirus species, little insect genomic information is known. The release of the Bombyx mori and Plutella xylostella genomes, the accumulation of EST sequences for several Lepidopteran species, and especially the availability of two genome-scale analysis tools, namely oligonucleotide microarrays and next generation sequencing (NGS), have facilitated expression studies to generate a rich picture of insect gene responses to baculovirus infections. This review presents current knowledge on the interaction dynamics of the baculovirus-insect system' which is relatively well studied in relation to nucleocapsid transportation, apoptosis, and heat shock responses, but is still poorly understood regarding responses involved in pro-survival pathways, DNA damage pathways, protein degradation, translation, signaling pathways, RNAi pathways, and importantly metabolic pathways for energy, nucleotide and amino acid production. We discuss how the two genome-scale transcriptomic tools can be applied for studying such pathways and suggest that proteomics and metabolomics can produce complementary findings to transcriptomic studies.

  12. A recombinant West Nile virus envelope protein vaccine candidate produced in Spodoptera frugiperda expresSF+ cells

    OpenAIRE

    Bonafé, Nathalie; Rininger, Joseph A.; Chubet, Richard G.; Foellmer, Harald G.; Fader, Stacey; Anderson, John F.; Bushmich, Sandra L.; Anthony, Karen; Ledizet, Michel; Fikrig, Erol; Koski, Raymond A.; Kaplan, Paul

    2008-01-01

    In this study, a recombinant truncated West Nile virus envelope protein antigen (rWNV-E) was produced in serum-free cultures of the expresSF+ insect cell line via baculovirus infection. This production system was selected based on its use in the production of candidate human and animal vaccine antigens. A defined fermentation and purification process for the rWNV-E antigen was established to control for purity and immunogenicity of each protein batch. The material formulated with aluminum hyd...

  13. Insect cells are superior to Escherichia coli in producing malaria proteins inducing IgG targeting PfEMP1 on infected erythrocytes

    Directory of Open Access Journals (Sweden)

    Joergensen Louise

    2010-11-01

    Full Text Available Abstract Background The PFD1235w Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1 antigen is associated with severe malaria in children and can be expressed on the surface of infected erythrocytes (IE adhering to ICAM1. However, the exact three-dimensional structure of this PfEMP1 and its surface-exposed epitopes are unknown. An insect cell and Escherichia coli based system was used to express single and double domains encoded by the pfd1235w var gene. The resulting recombinant proteins have been evaluated for yield and purity and their ability to induce rat antibodies, which react with the native PFD1235w PfEMP1 antigen expressed on 3D7PFD1235w-IE. Their recognition by human anti-malaria antibodies from previously infected Tanzanian donors was also analysed. Methods The recombinant proteins were run on SDS-PAGE and Western blots for quantification and size estimation. Insect cell and E. coli-produced recombinant proteins were coupled to a bead-based Luminex assay to measure the plasma antibody reactivity of 180 samples collected from Tanzanian individuals. The recombinant proteins used for immunization of rats and antisera were also tested by flow cytometry for their ability to surface label 3D7PFD1235w-IE. Results All seven pAcGP67A constructs were successfully expressed as recombinant protein in baculovirus-infected insect cells and subsequently produced to a purity of 60-97% and a yield of 2-15 mg/L. By comparison, only three of seven pET101/D-TOPO constructs expressed in the E. coli system could be produced at all with purity and yield ranging from 3-95% and 6-11 mg/L. All seven insect cell, but only two of the E. coli produced proteins induced antibodies reactive with native PFD1235w expressed on 3D7PFD1235w-IE. The recombinant proteins were recognized in an age- and transmission intensity-dependent manner by antibodies from 180 Tanzanian individuals in a bead-based Luminex assay. Conclusions The baculovirus based insect cell

  14. Insect cell culture in research: Indian scenario.

    Science.gov (United States)

    Sudeep, A B; Mourya, D T; Mishra, A C

    2005-06-01

    Insect cell cultures are widely used in viral diagnosis and biotechnology, for the production of recombinant proteins, viral pesticides and vaccines as well as in basic research in genetics, molecular biology, biochemistry, endocrinology and virology. Following KRP Singh's pioneering research in 1967, a large number of cell lines from diptera, hemiptera, and lepidopteran insects were established and characterized in India. With the availability of the modern tools in molecular biology and the advancements made in biotechnology, the indigenous cell lines may prove useful in creating a future without biohazardous chemical pesticides as well as producing life saving pharmaceuticals and vaccines for many diseases. This review summarizes information gathered regarding the insect cell lines established so far in India. It also covers the familiarization of the well characterized continuous cell lines and their potential applications. Special attention is given to virus susceptibility of the cell lines, the yield of virus with a comparative analysis with other conventional systems. The potential applications of dipteran and lepidopteran cell lines in agriculture and biotechnology are also briefly discussed for prospective studies.

  15. Recombinant Protein Production and Insect Cell Culture and Process

    Science.gov (United States)

    Spaulding, Glenn F. (Inventor); Goodwin, Thomas J. (Inventor); OConnor, Kim C. (Inventor); Francis, Karen M. (Inventor); Andrews, Angela D. (Inventor); Prewett, Tracey L. (Inventor)

    1997-01-01

    A process has been developed for recombinant production of selected polypeptides using transformed insect cells cultured in a horizontally rotating culture vessel modulated to create low shear conditions. A metabolically transformed insect cell line is produced using the culture procedure regardless of genetic transformation. The recombinant polypeptide can be produced by an alternative process using virtually infected or stably transformed insect cells containing a gene encoding the described polypeptide. The insect cells can also be a host for viral production.

  16. REPAT, a new family of proteins induced by bacterial toxins and baculovirus infection in Spodoptera exigua.

    NARCIS (Netherlands)

    Herrero, S.; Ansems, M.; Oers, M.M. van; Vlak, J.M.; Bakker, P.L.; Maagd, R.A. de

    2007-01-01

    Insect larvae spend most of their time eating and the digestive tract is the most crucial barrier for the entrance of many pathogens. In our study, suppression subtractive hybridization (SSH) was used to compare Spodoptera exigua midgut gene expression between larvae exposed to the Bacillus thuringi

  17. Radiosensitivity of cultured insect cells: I. Lepidoptera

    Energy Technology Data Exchange (ETDEWEB)

    Koval, T.M.

    1983-10-01

    The radiosensitivity of five lepidopteran insect cell lines representing five different genera has been investigated. These lines are: (1) TN-368, Trichoplusia ni; (2) IPLB-SF-1254, Spodoptera frugiperda; (3) IPLB-1075, Heliothis zea; (4) MRRL-CHl, clone GVl, Manduca sexta; and (5) IAL-PID2, Plodia interpunctella. The cell lines grew at different rates and had population doubling times that ranged from 19 to 52 hr. All of the lines are highly heteroploid and have approximate chromosome numbers near or above 100. The chromosomes are very small. All of the lines are extremely radioresistant; cell populations are able to recover from 260 kVp X-ray exposures up to and including 400 Gy, the highest dose examined. Cell survival curves were obtainable for only the TN-368 and IPLB-SF-1254 lines. The TN-368 cells displayed a biphasic survival response with D/sub 0/, d/sub q/, and n values of 65.7 and 130.2 Gy, 9.0 and -36.1 Gy, and 1.2 and 0.8, respectively, for the steep and shallow portions of the curve. The IPLB-SF-1254 cells had a D/sub 0/ of 63.9 Gy. D/sub q/ of 19.0 Gy, and n value of 1.4. These studies provide definitive evidence of the radioresistance of lepidopteran cells, and suggest that this radioresistance is a characteristic of lepidopteran insects.

  18. Insect cell transformation vectors that support high level expression and promoter assessment in insect cell culture

    Science.gov (United States)

    A somatic transformation vector, pDP9, was constructed that provides a simplified means of producing permanently transformed cultured insect cells that support high levels of protein expression of foreign genes. The pDP9 plasmid vector incorporates DNA sequences from the Junonia coenia densovirus th...

  19. Identified nerve cells and insect behavior.

    Science.gov (United States)

    Comer, C M; Robertson, R M

    2001-03-01

    Studies of insect identified neurons over the past 25 years have provided some of the very best data on sensorimotor integration; tracing information flow from sensory to motor networks. General principles have emerged that have increased the sophistication with which we now understand both sensory processing and motor control. Two overarching themes have emerged from studies of identified sensory interneurons. First, within a species, there are profound differences in neuronal organization associated with both the sex and the social experience of the individual. Second, single neurons exhibit some surprisingly rich examples of computational sophistication in terms of (a) temporal dynamics (coding superimposed upon circadian and shorter-term rhythms), and also (b) what Kenneth Roeder called "neural parsimony": that optimal information can be encoded, and complex acts of sensorimotor coordination can be mediated, by small ensembles of cells. Insect motor systems have proven to be relatively complex, and so studies of their organization typically have not yielded completely defined circuits as are known from some other invertebrates. However, several important findings have emerged. Analysis of neuronal oscillators for rhythmic behavior have delineated a profound influence of sensory feedback on interneuronal circuits: they are not only modulated by feedback, but may be substantially reconfigured. Additionally, insect motor circuits provide potent examples of neuronal restructuring during an organism's lifetime, as well as insights on how circuits have been modified across evolutionary time. Several areas where future advances seem likely to occur include: molecular genetic analyses, neuroecological syntheses, and neuroinformatics--the use of digital resources to organize databases with information on identified nerve cells and behavior. PMID:11163685

  20. Plasma membranes from insect midgut cells

    Directory of Open Access Journals (Sweden)

    Walter R. Terra

    2006-06-01

    Full Text Available Plasma membranes from insect midgut cells are separated into apical and basolateral domains. The apical domain is usually modified into microvilli with a molecular structure similar to other animals. Nevertheless, the microvillar structure should differ in some insects to permit the traffic inside them of secretory vesicles that may budd laterally or pinch-off from the tips of microvilli. Other microvillar modifications are associated with proton-pumping or with the interplay with an ensheathing lipid membrane (the perimicrovilllar membrane observed in the midgut cells of hemipterans (aphids and bugs. The perimicrovillar membranes are thought to be involved in amino acid absorption from diluted diets. The microvillar and perimicrovillar membranes have densities (and protein content that depend on the insect taxon. The role played by the microvillar and perimicrovillar proteins in insect midgut physiology is reviewed here trying to provide a coherent picture of data and highlighting further research areas.As membranas plasmáticas das células intestinais dos insetos apresentam um domínio apical e outro basal. O domínio apical é geralmente modificado em microvilosidades com organização molecular similar a de outros animais, embora possam diferir naqueles insetos que apresentam vesículas secretoras em trânsito que brotam lateralmente ou destacam-se das extremidades das microvilosidades. Outras modificações microvilares estão associadas a bombeamento de prótons ou a interrelações com uma membrana lipídica (a membrana perimicrovilar que reveste as microvilosidades de células intestinais de hemípteros (pulgões e percevejos. Admite-se que as membranas perimicrovilares estejam envolvidas na absorção de aminoácidos a partir de dietas diluídas. As membranas microvilares e perimicrovilares tem densidades distintas (e conteúdo protéico que dependem do táxon do inseto. O papel desempenhado pelas proteínas microvilares e

  1. Cytochrome c and insect cell apoptosis

    Institute of Scientific and Technical Information of China (English)

    Kai-Yu Liu; Hong Yang; Jian-Xin Peng; Hua-Zhu Hong

    2012-01-01

    The role ofcytochrome c in insect cell apoptosis has drawn considerable attention and has been subject to considerable controversy.In Drosophila,the majority of studies have demonstrated that cytochrome c may not be involved in apoptosis,although there are conflicting reports.Cytochrome c is not released from mitochondria into the cytosol and activation of the initiator caspase Dronc or effector caspase Drice is not associated with cytochrome c during apoptosis in Drosophila SL2 cells or BG2 cells.Cytochrome c failed to induce caspase activation and promote caspase activation in Drosophila cell lysates,but remarkably caused caspase activation in extracts from human cells.Knockdown of cytochrome c does not protect cells from apoptosis and over-expression of cytochrome c also does not promote apoptosis.Structural analysis has revealed that cytochrome c is not required for Dapaf-1 complex assembly.In Lepidoptera,the involvement of cytochrome c in apoptosis has been demonstrated by the accumulating evidence.Cytochrome c release from mitochondria into cytosol has been observed in different cell lines such as Spodoptera frugiperda Sf9,Spodoptera litura S1-1 and Lymantria dispar LdFB.Silencing of cytochrome c expression significantly affected apoptosis and activation of caspase and the addition of cytochrome c to cell-free extracts results in caspase activation,suggesting the activation of caspase is dependent on cytochrome c.Although Apaf- 1 has not been identified in Lepidoptera,the inhibitor of apoptosome formation can inhibit apoptosis and caspase activation.Cytochrome c may be exclusively required for Lepidoptera apoptosis.

  2. Functional expression of mammalian receptors and membrane channels in different cells.

    Science.gov (United States)

    Eifler, Nora; Duckely, Myriam; Sumanovski, Lazar T; Egan, Terrance M; Oksche, Alexander; Konopka, James B; Lüthi, Anita; Engel, Andreas; Werten, Paul J L

    2007-08-01

    In native tissues, the majority of medically important membrane proteins is only present at low concentrations, making their overexpression in recombinant systems a prerequisite for structural studies. Here, we explore the commonly used eukaryotic expression systems-yeast, baculovirus/insect cells (Sf9) and Semliki Forest Virus (SFV)/mammalian cells-for the expression of seven different eukaryotic membrane proteins from a variety of protein families. The expression levels, quality, biological activity, localization and solubility of all expressed proteins are compared in order to identify the advantages of one system over the other. SFV-transfected mammalian cell lines provide the closest to native environment for the expression of mammalian membrane proteins, and they exhibited the best overall performance. But depending on the protein, baculovirus-infected Sf9 cells performed almost as well as mammalian cells. The lowest expression levels for the proteins tested here were obtained in yeast.

  3. DNA content analysis of insect cell lines by flow cytometry

    OpenAIRE

    Léry, Xavier; Charpentier, Guy; Belloncik, Serge

    1999-01-01

    The DNA content of insect cell lines (6 lepidoptera, 1 coleoptera and 1 diptera) was determined by flow cytometry. The DNA profiles of the 8 cell lines tested were different. They were characterized by the presence of several peaks (2 to 7) corresponding to different ploidy levels, by differences in the fluorescence intensity of each peak and by the proportion of cells in each peak. Two cell lines (Cf124 and BmN) were constituted of 2 distinct populations of cells. The DNA profiles of the cel...

  4. Recombinant scorpion insectotoxin AaIT kills specifically insect cells but not human cells

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The nucleotide sequence deduced from the amino acid sequence of the scorpion insectotoxin AaIT was chemically synthesized and was expressed in Escherichia coli. The authenticity of this in vitro expressed peptide was confirmed by N-terminal peptide sequencing. Two groups of bioassays, artificial diet incorporation assay and contact insecticidal effect assay, were carried out separately to verify the toxicity of this recombinant toxin. At the end of a 24 h experimental period, more than 60% of the testing diamondback moth (Plutella xylostella) larvae were killed in both groups with LCs0 value of 18.4 uM and 0.70 μM respectively. Cytotoxicity assay using cultured Sf9 insect cells and MCF-7 human cells demonstrated that the toxin AaIT had specific toxicity against insect cells but not human cells. Only 0.13 μM recombinant toxin was needed to kill 50% of cultured insect cells while as much as 1.3μM toxin had absolutely no effect on human cells. Insect cells produced obvious intrusions from their plasma membrane before broken up. We infer that toxin AaIT bind to a putative sodium channel in these insect cells and open the channel persistently, which would result in Na+ influx and finally cause destruction of insect cells.

  5. Motoneurons, DUM cells, and sensory neurons in an insect thoracic ganglion: a tracing study in the stick insect Carausius morosus.

    Science.gov (United States)

    Goldammer, Jens; Büschges, Ansgar; Schmidt, Joachim

    2012-02-01

    Anatomical features of leg motoneurons, dorsal unpaired median (DUM) cells, and sensory neurons in stick insect mesothoracic ganglia were examined using fluorescent dye backfills of lateral nerves. Structures were analyzed in whole-mounts of ganglia and transverse sections. Numbers of motoneurons and details of their structure by far exceed previously published data. The general neuroanatomical layout of motoneurons matches the general orthopteran pattern. Cell bodies of excitatory motoneurons form clusters in the lateral cortex, dendrites branch mainly in the dorsal neuropil. We identified nine DUM cells, six of which have axons in nerve nl5. Most sensory fibers terminate in the ventral association center (VAC). Twenty-three small cell bodies located close to the soma of the fast extensor tibiae motoneuron likely belong to strand receptors. Labeled structures are compared with previously published data from stick insects and other orthopterous insects. PMID:21618233

  6. Biofuel cell backpacked insect and its application to wireless sensing.

    Science.gov (United States)

    Shoji, Kan; Akiyama, Yoshitake; Suzuki, Masato; Nakamura, Nobuhumi; Ohno, Hiroyuki; Morishima, Keisuke

    2016-04-15

    This study investigated an enzymatic biofuel cell (BFC) which can be backpacked by cockroaches. The BFC generates electric power from trehalose in insect hemolymph by the trehalase and glucose dehydrogenase (GDH) reaction systems which dehydrogenate β-glucose obtained by hydrolyzing trehalose. First, an insect-mountable BFC (imBFC) was designed and fabricated with a 3D printer. The electrochemical reaction of anode-modified poly-L-lysine, vitamin K3, diaphorase, nicotinamide adenine dinucleotide, GDH and poly(sodium 4-styrenesulfonate) in the imBFC was evaluated and an oxidation current of 1.18 mAcm(-2) (at +0.6 V vs. Ag|AgCl) was observed. Then, the performance of the imBFC was evaluated and a maximum power output of 333 μW (285 μW cm(-)(2)) (at 0.5 V) was obtained. Furthermore, driving of both an LED device and a wireless temperature and humidity sensor device were powered by the imBFC. These results indicate that the imBFC has sufficient potential as a battery for novel ubiquitous robots such as insect cyborgs.

  7. P220-S Dual-Purpose Insect Cell Expression Vector for Transient Transfection and Baculovirus Generation

    OpenAIRE

    Loomis, K.; ROCKWELL, C; Sternard, H.; Novy, R.

    2007-01-01

    Baculovirus-mediated expression has proven to be a robust method of generating recombinant proteins from insect cells. However, generating baculovirus recombinants using traditional techniques is time consuming and tedious. To accelerate the process of insect cell expression, EMD developed a rapid transient transfection-based approach, the InsectDirect System. This approach is well suited for the rapid generation of small to moderate amounts of recombinant protein. For situations that demand ...

  8. INFLUENCE OF MIXING DEVICE ON SERUM-FREE CULTIVATION OF INSECT CELLS IN SPINNER FLASKS

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    IntroductionThe cultivation of insect cells is presently gainingin popularity mainly for the expression of high-valueheterologous proteins using genetically engineeredbaculoviruseslll. Efficient production of these proteinsrequires a suitable insect cell culture system, includingthe improved cell line with high productivity, suitableculture media and favorable environment that couldstrongly support cell growth.Tn-SBI-4 (Tns ) is a novel cell line establishedfrom Tnt midgut tissue, This cell line proved topo...

  9. A Continuous-Exchange Cell-Free Protein Synthesis System Based on Extracts from Cultured Insect Cells

    OpenAIRE

    Marlitt Stech; Quast, Robert B.; Rita Sachse; Corina Schulze; Wüstenhagen, Doreen A.; Stefan Kubick

    2014-01-01

    In this study, we present a novel technique for the synthesis of complex prokaryotic and eukaryotic proteins by using a continuous-exchange cell-free (CECF) protein synthesis system based on extracts from cultured insect cells. Our approach consists of two basic elements: First, protein synthesis is performed in insect cell lysates which harbor endogenous microsomal vesicles, enabling a translocation of de novo synthesized target proteins into the lumen of the insect vesicles or, in the case ...

  10. Two-stage baculovirus production in insect-cell bioreactors.

    NARCIS (Netherlands)

    Lier, van F.L.J.

    1995-01-01

    Baculoviruses are insect-pathogenic viruses with a narrow host range. The viruses can be an alternative to chemical insecticides. From research aimed at improving the efficacy of the viruses in insect control another application evolved: the use of the baculovirus to express foreign proteins in inse

  11. COMPARATIVE ASPECTS OF PLANT-CELL WALL DIGESTION IN INSECTS

    NARCIS (Netherlands)

    PRINS, RA; KREULEN, DA

    1991-01-01

    Although many phytophagous and wood-eating invertibrates form their own cellulases, there is an overwhelming variety of symbioses between plant- and wood-utilising insects and microorganisms. In one type of symbiosis (endosymbiosis), insects (rhinoceros beetle, cockroach, lower termites) host cellul

  12. Production of human c-myc protein in insect cells infected with a baculovirus expression vector.

    OpenAIRE

    Miyamoto, C.; Smith, G. E.; Farrell-Towt, J; Chizzonite, R.; Summers, M D; Ju, G.

    1985-01-01

    A cDNA fragment coding for human c-myc was inserted into the genome of the baculovirus Autographa californica nuclear polyhedrosis virus adjacent to the strong polyhedrin promoter. Insect cells infected with the recombinant virus produced significant amounts of c-myc protein, which constituted the major phosphoprotein component in these cells. By immunoprecipitation and immunoblot analysis, two proteins of 61 and 64 kilodaltons were detected with c-myc-specific antisera. The insect-derived pr...

  13. A novel baculovirus vector for the production of nonfucosylated recombinant glycoproteins in insect cells

    OpenAIRE

    Mabashi-Asazuma, Hideaki; Kuo, Chu-Wei; Khoo, Kay-Hooi; Jarvis, Donald L

    2013-01-01

    Glycosylation is an important attribute of baculovirus-insect cell expression systems, but some insect cell lines produce core α1,3-fucosylated N-glycans, which are highly immunogenic and render recombinant glycoproteins unsuitable for human use. To address this problem, we exploited a bacterial enzyme, guanosine-5′-diphospho (GDP)-4-dehydro-6-deoxy-d-mannose reductase (Rmd), which consumes the GDP-l-fucose precursor. We expected this enzyme to block glycoprotein fucosylation by blocking the ...

  14. Modifying an Insect Cell N-Glycan Processing Pathway Using CRISPR-Cas Technology.

    Science.gov (United States)

    Mabashi-Asazuma, Hideaki; Kuo, Chu-Wei; Khoo, Kay-Hooi; Jarvis, Donald L

    2015-10-16

    Fused lobes (FDL) is an enzyme that simultaneously catalyzes a key trimming reaction and antagonizes elongation reactions in the insect N-glycan processing pathway. Accordingly, FDL function accounts, at least in part, for major differences in the N-glycosylation patterns of glycoproteins produced by insect and mammalian cells. In this study, we used the CRISPR-Cas9 system to edit the fdl gene in Drosophila melanogaster S2 cells. CRISPR-Cas9 editing produced a high frequency of site-specific nucleotide insertions and deletions, reduced the production of insect-type, paucimannosidic products (Man3GlcNAc2), and led to the production of partially elongated, mammalian-type complex N-glycans (GlcNAc2Man3GlcNAc2) in S2 cells. As CRISPR-Cas9 has not been widely used to analyze or modify protein glycosylation pathways or edit insect cell genes, these results underscore its broad utility as a tool for these purposes. Our results also confirm the key role of FDL at the major branch point distinguishing insect and mammalian N-glycan processing pathways. Finally, the new FDL-deficient S2 cell derivative produced in this study will enable future bottom-up glycoengineering efforts designed to isolate insect cell lines that can efficiently produce recombinant glycoproteins with chemically predefined oligosaccharide side-chain structures.

  15. Baculovirus as a highly efficient expression vector in insect and mammalian cells

    Institute of Scientific and Technical Information of China (English)

    Yu-chen HU

    2005-01-01

    Baculovirus has been widely used for the production of recombinant proteins in insect cells. Since the finding that baculovirus can efficiently transduce mammalian cells, the applications of baculovirus have been greatly expanded. The prospects and drawbacks of baculovirus-mediated gene expression, either in insect or in mammalian cells, are reviewed. Recent progresses in expanding the applications to studies of gene regulation, viral vector preparation, in vivo and ex vivo gene therapy studies, generation of vaccine vectors, etc are discussed and the efforts directed towards overcoming the existing bottlenecks are particularly emphasized.

  16. In vitro assay for HCV serine proteinase expressed in insect cells

    Institute of Scientific and Technical Information of China (English)

    Li-Hua Hou; Gui-Xin Du; Rong-Bin Guan; Yi-Gang Tong; Hai-Tao Wang

    2003-01-01

    AIM: To produce the recombinant NS3 protease of hepatitis C virus with enzymatic activity in insect cells.METHODS: The gene of HCV serine proteinase domain which encodes 181 amino acids was inserted into pFastBacHTc and the recombinant plasmid pFBCNS3N was transformed into DH10Bac competent cells for transposition.After the recombinant bacmids had been determined to be correct by both blue-white colonies and PCR analysis, the isolated bacmid DNAs were transfected into Sf9 insect cells.The bacmids DNA was verified to replicate in insect cells and packaged into baculovirus particles via PCR and electronic microscopic analysis. The insect cells infected with recombinant baculovirus were determined by SDS-PAGE and Western-blot assays. The recombinant protein was soluted in N-lauryl sarcosine sodium (NLS) and purifed by metalchelated-affinity chromatography, then the antigenicity of recombinant protease was determined by enzyme-linked immunoabsorbant assay and its enzymatic activity was detected.RESULTS: The HCV NS3 protease domain was expressed in insect cells at high level and it was partially solved in NLS.Totally 0.2 mg recombinant serine proteinase domain with high purity was obtained by metal-chelated-affinity chromatography from 5×107 cells, and both antigenicity and specificity of the protein were evaluated to be high when used as antigen to detect hepatitis C patients′ sera in indirect ELISA format. In vitro cleavage assay corroborated its enzymatic activity.CONCLUSION: The recombinant HCV NS3 proteinase expressed by insect cells is a membrane-binding protein with good antigenicity and enzymatic activity.

  17. Arbovirus vaccines: opportunities for the baculovirus-insect cell expression system

    NARCIS (Netherlands)

    Metz, S.W.H.; Pijlman, G.P.

    2011-01-01

    The baculovirus-insect cell expression system is a well-established technology for the production of heterologous viral (glyco)proteins in cultured cells, applicable for basic scientific research as well as for the development and production of vaccines and diagnostics. Arboviruses form an emerging

  18. No requirement of HCV 5'NCR for HCV-like particles assembly in insect cells

    Institute of Scientific and Technical Information of China (English)

    Wei Zhao; Guo-Yang Liao; Yah-Jun Jiang; Shu-De Jiang

    2003-01-01

    AIM: To express all three HCV structural proteins in the presence or absence of HCV 5'NCR to investigate the requirement of 5'NCR for the assembly of HCV-like particles in insect cells.METHODS: HCV structural protein encoding sequences CE1E2 and 5'NCR-CE1E2 were amplified with PCR.Recombinant baculovirus were constructed with recombinant DNA techniques. HCV structural proteins expressed in insect cells were analyzed by immunofluorescence and SDS-PAGE.Immunoprecipitation experiment of insect cell lysates with anti-E2 monodonal antibody (Mab) was carried out and the immunoprecipitated proteins were subjected to SDS-PAGE and immunoblotting with anti-C, anti-E2 Mabs and HCV positive serum. The virus-like particles in insect cells were visualized by electron microscopy (EM). The HCV-like particles were purified by sucrose gradient centrifugation and identified by EM and immune aggregation EM.RESULTS: The recombinant baculovirus reBV/CE1E2containing HCV C, E1, E2 genes and reBV/CS containing the same structural protein genes plus 5'NCR were constructed. The insect cells infected with either reBV/CE1E2or reBV/CS expressed HCV C, E1 and E2 proteins with a molecular weight of 20 kD, 35 kD and 66 kD respectively.The results of immunoprecipitation and the immunoblotting revealed the coimmunoprecipitation of C, E1, and E2proteins, indicating the interaction of HCV structural proteins expressed in insect cells. Electron microscopy of insect cells infected with reBV/CE1E2 or reBV/CS demonstrated spherical particles (40 to 60 nm in diameter)similar to the HCV virions from sera or hepatic tissues of HCV infected humans. The HCV-like particles were partially purified by sucrose gradient centrifugation, and the purified VLPs showed immuno-reactivity with anti-HCV antibodies.CONCLUSION: HCV 5'NCR is not required for the assembly of HCV-like particles in insect cells, HCV core and envelope proteins are sufficient for viral particle formation.

  19. Baculovirus ETL promoter acts as a shuttle promoter between insect cells and mammalian cells

    Institute of Scientific and Technical Information of China (English)

    Yu-kou LIU; Chih-chieh CHU; Tzong-yuan WU

    2006-01-01

    Aim:To identify a shuttle promoter that can mediate gene expression in both insect cells and mammalian cells to facilitate the development of a baculovirus vector-based mammalian cell gene delivery vehicle.Methods:Recombinant baculoviruses carrying the β-galactosidase reporter gene under the control of an early to late(ETL)promoter of the Autographa califomica multiple nuclear polyhedrosis virus(AcMNPV)or a cytomegalovirus immediate early promoter (CMV promoter)were constructed.COS1,HeLa,CHO-K1,hFob1.19,and MCF-7 mammalian cells were tested for the expression of β-galactosidase.Results:ETL promoter activity was higher in bone-derived hFob1.19 than in COS1,HeLa,CHOK1,or MCF-7 mammalian cells.The transient plasmid transfection assay indicated that ETL promoter activity in mammalian cells was dependent on baculovirus gene expression.Conclusion:ETL promoter activity in mammalian cells is baculovirus gene expression-dependent,and the shuttle promoter will facilitate the application of baculovirus expression vectors in mammalian cell expression systems and for gene therapy.

  20. Development of Serum-Free Media for Lepidopteran Insect Cell Lines.

    Science.gov (United States)

    Chan, Leslie C L; Reid, Steven

    2016-01-01

    Baculovirus-based Insect Cell Technology (ICT) is widely used for the expression of recombinant heterologous proteins and baculovirus bioinsecticides, and has recently gained momentum as a commercial manufacturing platform for human and veterinary vaccines. The three key components of ICT are the Lepidopteran insect cell line, the baculovirus vector, and the growth medium. Insect cell growth media have evolved significantly in the past five decades, from basal media supplemented with hemolymph or animal serum, to highly optimized serum-free media and feeds (SFM and SFF) capable of supporting very high cell densities and recombinant protein yields. The substitution of animal sera with protein hydrolysates in SFM results in greatly reduced medium costs and much improved process scalability. However, both sera and hydrolysates share the disadvantage of lot-to-lot variability, which is detrimental to process reproducibility. Hence, the industrialization of ICT would benefit greatly from chemically defined media (CDM) for insect cells, which are not yet commercially available. On the other hand, applications such as baculovirus bioinsecticides would need truly low cost serum-free media and feeds (LC-SFM and LC-SFF) for economic viability, which require the substitution of a majority of expensive added amino acids with even higher levels of hydrolysates, hence increasing the risk of a variable process. CDM developments are anticipated to benefit both conventional and low cost ICT applications, by identifying key growth factors in hydrolysates for more targeted media and feed design. PMID:26820858

  1. Expression, purification and serological analysis of hepatocellular carcinoma associated antigen HCA587 in insect cells

    Institute of Scientific and Technical Information of China (English)

    Bing Li; Hong-Yan Wu; Xiao-Ping Qian; Yan Li; Wei-Feng Chen

    2003-01-01

    AIM: In order to assess hepatocellular carcinoma associated antigen HCA587 as a potential target for immunotherapy,the Bac-to-Bac expression system was used to express recombinant protein HCA587 in insect cells.METHODS: The cDNA encoding HCA587 gene was cloned into donor vector pFasBacHtb and recombinant pFasBac Htb587 was transformed into competent cells DH10Bac.Recombinant Bacmid-587 was transfected into Sf9 insect cells using CELLFECTIN, Recombinant HCA587 protein was produced in Sf9 insect cells after infection with recombinant baculovirus, and was purified using Ni-NTA resin. Sera from HCC patients were also screened using recombinant protein HCA587.RESULTS: The molecular weight of the recombinant protein HCA587 expressed in insect cells was approximately 43kd.Western blot results proved the recombinant protein HCA587had the similar antigenicity with its native counterpart.Serological analysis told that the rate of seroreactivity to HCA587 was not high in HCC patients.CONCLUSION: The recombinant protein HCA587 was successfully expressed and purified using Bac-to-Bac expression system. It paved the way for generation of specific antibody and investigation of immunohistochemical analysis and immune responses of HCC in the future.

  2. Adenylate kinase 2 (AK2 promotes cell proliferation in insect development

    Directory of Open Access Journals (Sweden)

    Chen Ru-Ping

    2012-09-01

    Full Text Available Abstract Background Adenylate kinase 2 (AK2 is a phosphotransferase that catalyzes the reversible reaction 2ADP(GDP ↔ ATP(GTP + AMP and influences cellular energy homeostasis. However, the role of AK2 in regulating cell proliferation remains unclear because AK2 has been reported to be involved in either cell proliferation or cell apoptosis in different cell types of various organisms. Results This study reports AK2 promotion of cell proliferation using the lepidopteran insect Helicoverpa armigera and its epidermal cell line HaEpi as models. Western blot analysis indicates that AK2 constitutively expresses in various tissues during larval development. Immunocytochemistry analysis indicates that AK2 localizes in the mitochondria. The recombinant expressed AK2 in E. coli promotes cell growth and viability of HaEpi cell line by 3-(4, 5-Dimethylthiazol-2-yl-2, 5-diphenyltetrazolium bromide (MTT assay. AK2 knockdown in larvae by RNA interference causes larval growth defects, including body weight decrease and development delay. AK2 knockdown in larvae also decreases the number of circulating haemocytes. The mechanism for such effects might be the suppression of gene transcription involved in insect development caused by AK2 knockdown. Conclusion These results show that AK2 regulates cell growth, viability, and proliferation in insect growth and development.

  3. A bacterial signal peptidase enhances processing of a recombinant single chain antibody fragment in insect cells

    NARCIS (Netherlands)

    Ailor, E; Pathmanathan, J; Jongbloed, JDH; Betenbaugh, MJ

    1999-01-01

    The production of an antibody single chain fragment (scFv) in insect cells was accompanied by the formation of an insoluble intracellular precursor even with the inclusion of the bee melittin signal peptide. The presence of the precursor polypeptide suggests a limitation in the processing of the sig

  4. Expression of the dyslexia candidate gene kiaa0319-like in insect cells

    NARCIS (Netherlands)

    Holster, S.; Oers, van M.M.; Roode, E.C.; Tsang, O.W.H.; Yeung, V.S.Y.; Vlak, J.M.; Waye, M.M.Y.

    2013-01-01

    The human kiaa0319-like gene is one of the candidate genes for developmental dyslexia, but the exact function of the encoded KIAA0319L (KL) protein is not known. To allow functional analysis a purified, biologically active KL protein is required. The kiaa0319-like gene was expressed in insect cells

  5. A re-usable wave bioreactor for protein production in insect cells.

    Science.gov (United States)

    Scholz, J; Suppmann, S

    2016-01-01

    Wave-mixed bioreactors have increasingly replaced stainless steel stirred tank reactors in seed inoculum productions and mammalian cell-based process developments. Pre-sterilized, single-use plastic bags are used for cultivation, eliminating the risk of cross-contamination and cleaning procedures. However, these advantages come with high consumable costs which is the main barrier to more uptakes of the technology by academic institutions. As an academic Core Facility that faces high demand in protein production from insect cells, we have therefore developed a cost-effective alternative to disposable wave bags. In our study we identified: •A re-usable wave shaken polycarbonate bioreactor for protein production in insect cells achieves protein yields comparable to disposable bags.•The advantages of this re-usable bioreactor are low costs, long life cycle, flexible configuration of accessories and convenient handling due to its rigid shape. PMID:27556015

  6. Clustering of adhesion receptors following exposure of insect blood cells to foreign surfaces.

    Science.gov (United States)

    Nardi, James B; Zhuang, Shufei; Pilas, Barbara; Bee, Charles Mark; Kanost, Michael R

    2005-05-01

    Cell-mediated immune responses of insects involve interactions of two main classes of blood cells (hemocytes) known as granular cells and plasmatocytes. In response to a foreign surface, these hemocytes suddenly transform from circulating, non-adherent cells to cells that interact and adhere to each other and the foreign surface. This report presents evidence that during this adhesive transformation the extracellular matrix (ECM) proteins lacunin and a ligand for peanut agglutinin (PNA) lectin are released by granular cells and bind to surfaces of both granular cells and plasmatocytes. ECM protein co-localizes on cell surfaces with the adhesive receptors integrin and neuroglian, a member of the immunoglobulin superfamily. The ECM protein(s) secreted by granular cells are hypothesized to interact with adhesion receptors such as neuroglian and integrin by cross linking and clustering them on hemocyte surfaces. This clustering of receptors is known to enhance the adhesiveness (avidity) of interacting mammalian immune cells. The formation of ring-shaped clusters of these adhesion receptors on surfaces of insect immune cells represents an evolutionary antecedent of the mammalian immunological synapse. PMID:15894002

  7. Construction and Characterization of Insect Cell-Derived Influenza VLP: Cell Binding, Fusion, and EGFP Incorporation

    Directory of Open Access Journals (Sweden)

    Yi-Shin Pan

    2010-01-01

    Full Text Available We have constructed virus-like particles (VLPs harboring hemagglutinin (HA, neuraminidase (NA, matrix protein 1 (M1 ,and proton channel protein (M2 using baculovirus as a vector in the SF9 insect cell. The size of the expressed VLP was estimated to be ~100 nm by light scattering experiment and transmission electron microscopy. Recognition of HA on the VLP surface by the HA2-specific monoclonal antibody IIF4 at acidic pH, as probed by surface plasmon resonance, indicated the pH-induced structural rearrangement of HA. Uptake of the particle by A549 mediated by HA-sialylose receptor interaction was visualized by the fluorescent-labeled VLP. The HA-promoted cell-virus fusion activity was illustrated by fluorescence imaging on the Jurkat cells incubated with rhodamine-loaded VLP performed at fusogenic pH. Furthermore, the green fluorescence protein (GFP was fused to NA to produce VLP with a pH-sensitive probe, expanding the use of VLP as an antigen carrier and a tool for viral tracking.

  8. Insect Growth Regulators for Insect Pest Control*

    OpenAIRE

    TUNAZ, Hasan

    2004-01-01

    Insecticides with growth regulating properties (IGR) may adversely affect insects by regulating or inhibiting specific biochemical pathways or processes essential for insect growth and development. Some insects exposed to such compounds may die due to abnormal regulation of hormone-mediated cell or organ development. Other insects may die either from a prolonged exposure at the developmental stage to other mortality factors (susceptibility to natural enemies, environmental conditions etc) or ...

  9. Long-term, large scale cryopreservation of insect cells at -80 °C.

    Science.gov (United States)

    Vyletova, Lucie; Rennalls, La'Verne P; Wood, Kirstin J L; Good, Valerie M

    2016-03-01

    Standard tissue culture methods advise freezing cells in small aliquots (≤1 × 10(7) cells in 1 mL), and storing in liquid nitrogen. This is inconvenient for laboratories culturing large quantities of insect cells for recombinant baculovirus expression, owing to the length of time taken to produce large scale cultures from small aliquots of cells. Liquid nitrogen storage requires use of specialized cryovials, personal protective equipment and oxygen monitoring systems. This paper describes the long-term, large scale cryopreservation of 8 × 10(8) insect cells at -80 °C, using standard 50 mL conical tubes to contain a 40 mL cell suspension. Sf9, Sf21 and High 5 cells were recovered with a viability > 90 % after storage for one year under these conditions, which compared favorably with the viability of cells stored in liquid nitrogen for the same length of time. Addition of green fluorescent protein encoding baculovirus demonstrated that cells were "expression ready" immediately post thaw. Our method enables large scale cultures to be recovered rapidly from stocks cryopreserved at -80 °C, thus avoiding the inconvenience, hazards and expense associated with liquid nitrogen.

  10. Effective chikungunya virus-like particle vaccine produced in insect cells.

    Directory of Open Access Journals (Sweden)

    Stefan W Metz

    Full Text Available The emerging arthritogenic, mosquito-borne chikungunya virus (CHIKV causes severe disease in humans and represents a serious public health threat in countries where Aedes spp mosquitoes are present. This study describes for the first time the successful production of CHIKV virus-like particles (VLPs in insect cells using recombinant baculoviruses. This well-established expression system is rapidly scalable to volumes required for epidemic responses and proved well suited for processing of CHIKV glycoproteins and production of enveloped VLPs. Herein we show that a single immunization with 1 µg of non-adjuvanted CHIKV VLPs induced high titer neutralizing antibody responses and provided complete protection against viraemia and joint inflammation upon challenge with the Réunion Island CHIKV strain in an adult wild-type mouse model of CHIKV disease. CHIKV VLPs produced in insect cells using recombinant baculoviruses thus represents as a new, safe, non-replicating and effective vaccine candidate against CHIKV infections.

  11. New PDMP analogues inhibit process outgrowth in an insect cell line.

    Science.gov (United States)

    Slavish, Jacob P; Friel, Donna K; Oland, Lynne A; Polt, Robin

    2004-03-22

    d-threo-1-Phenyl-2-aminodecanoyl-3-morpholinopropanol (d-threo-PDMP) has previously been shown to inhibit the biosynthesis of glycosphingolipids (GSLs) in mammals and mammalian cell lines by the inhibition of glucosylceramide synthase. New d-threo-PDMP analogues were synthesized from d-serine, and found to suppress neurite extension in an embryonic insect cell line from the moth Manduca sexta, and in explanted neural tissue from insect pupae. Inhibition occurred at lower concentrations than d-threo-PDMP. The observed suppression of neurite formation was found to be reversible after the removal of the compounds. Due to their small size and short life cycle, M. sexta is shown to be an ideal model organism for studies of GSL effects in cellular development, and for drug development studies. PMID:15006387

  12. Protein Expression in Insect and Mammalian Cells Using Baculoviruses in Wave Bioreactors.

    Science.gov (United States)

    Kadwell, Sue H; Overton, Laurie K

    2016-01-01

    Many types of disposable bioreactors for protein expression in insect and mammalian cells are now available. They differ in design, capacity, and sensor options, with many selections available for either rocking platform, orbitally shaken, pneumatically mixed, or stirred-tank bioreactors lined with an integral disposable bag (Shukla and Gottschalk, Trends Biotechnol 31(3):147-154, 2013). WAVE Bioreactors™ were among the first disposable systems to be developed (Singh, Cytotechnology 30:149-158, 1999). Since their commercialization in 1999, Wave Bioreactors have become routinely used in many laboratories due to their ease of operation, limited utility requirements, and protein expression levels comparability to traditional stirred-tank bioreactors. Wave Bioreactors are designed to use a presterilized Cellbag™, which is attached to a rocking platform and inflated with filtered air provided by the bioreactor unit. The Cellbag can be filled with medium and cells and maintained at a set temperature. The rocking motion, which is adjusted through angle and rock speed settings, provides mixing of oxygen (and CO2, which is used to control pH in mammalian cell cultures) from the headspace created in the inflated Cellbag with the cell culture medium and cells. This rocking motion can be adjusted to prevent cell shear damage. Dissolved oxygen and pH can be monitored during scale-up, and samples can be easily removed to monitor other parameters. Insect and mammalian cells grow very well in Wave Bioreactors (Shukla and Gottschalk, Trends Biotechnol 31(3):147-154, 2013). Combining Wave Bioreactor cell growth capabilities with recombinant baculoviruses engineered for insect or mammalian cell expression has proven to be a powerful tool for rapid production of a wide range of proteins.

  13. Nanofibers and nanoparticles from the insect-capturing adhesive of the Sundew (Drosera) for cell attachment

    OpenAIRE

    Zhang Mingjun; Lenaghan Scott C; Xia Lijin; Dong Lixin; He Wei; Henson William R; Fan Xudong

    2010-01-01

    Abstract Background The search for naturally occurring nanocomposites with diverse properties for tissue engineering has been a major interest for biomaterial research. In this study, we investigated a nanofiber and nanoparticle based nanocomposite secreted from an insect-capturing plant, the Sundew, for cell attachment. The adhesive nanocomposite has demonstrated high biocompatibility and is ready to be used with minimal preparation. Results Atomic force microscopy (AFM) conducted on the adh...

  14. Optimization of canine interleukin-12 production using a baculovirus insect cell expression system

    OpenAIRE

    de Pinheiro, Cristiane Garboggini Melo; Pedrosa, Mayara de Oliveira; Teixeira, Naiara Carvalho; Ano Bom, Ana Paula Dinis; van Oers, Monique M.; Oliveira, Geraldo Gileno de Sá

    2016-01-01

    Background Interleukin-12 is an important cytokine in mediating cellular immune responses. Results Recombinant single-chain canine IL-12 was produced in a baculovirus-insect cell system with the aim of conducting further studies on modulation of immune responses in dogs. To optimize the production of recombinant canine IL-12, a classical baculovirus and a modified vector (chitinase A and v-cathepsin knockout) were used containing a native or an optimized insert of canine IL-12. The optimized ...

  15. Expression and purification of recombinant vesicular glutamate transporter VGLUT1 using PC12 cells and High Five insect cells

    Directory of Open Access Journals (Sweden)

    Andersen Søren S.L.

    2004-01-01

    Full Text Available In synaptic vesicles, the estimated concentration of the excitatory amino acid glutamate is 100-150 mM. It was recently discovered that VGLUT1, previously characterized as an inorganic phosphate transporter (BNPI with 9-11 predicted transmembrane spanning domains, is capable of transporting glutamate. The expression and His-tag based purification of recombinant VGLUT1 from PC12 cells and High Five insect cells is described. Significantly better virus and protein expression was obtained using High Five rather than Sf9 insect cells. PC12 cell expressed VGLUT1 is functional but not the Baculovirus expressed protein. The lack of functionality of the Baculovirus expressed VGLUT1 is discussed. The data indicate that VGLUT1 readily oligomerizes/dimerizes. The data are discussed in the context of developing this system further in order to reconstitute vesicular glutamate uptake in vitro using lipid-detergent vesicles.

  16. Determination of Photoreceptor Cell Spectral Sensitivity in an Insect Model from In Vivo Intracellular Recordings.

    Science.gov (United States)

    McCulloch, Kyle J; Osorio, Daniel; Briscoe, Adriana D

    2016-01-01

    Intracellular recording is a powerful technique used to determine how a single cell may respond to a given stimulus. In vision research, intracellular recording has historically been a common technique used to study sensitivities of individual photoreceptor cells to different light stimuli that is still being used today. However, there remains a dearth of detailed methodology in the literature for researchers wishing to replicate intracellular recording experiments in the eye. Here we present the insect as a model for examining eye physiology more generally. Insect photoreceptor cells are located near the surface of the eye and are therefore easy to reach, and many of the mechanisms involved in vision are conserved across animal phyla. We describe the basic procedure for in vivo intracellular recording of photoreceptor cells in the eye of a butterfly, with the goal of making this technique more accessible to researchers with little prior experience in electrophysiology. We introduce the basic equipment needed, how to prepare a live butterfly for recording, how to insert a glass microelectrode into a single cell, and finally the recording procedure itself. We also explain the basic analysis of raw response data for determining spectral sensitivity of individual cell types. Although our protocol focuses on determining spectral sensitivity, other stimuli (e.g., polarized light) and variations of the method are applicable to this setup. PMID:26966935

  17. Mitochondrial response and calcium ion change in apoptotic insect cells induced by SfaMNPV

    Institute of Scientific and Technical Information of China (English)

    XIU Meihong; PENG Jianxin; HONG Huazhu

    2005-01-01

    Mitochondrial responses and changes of calcium ions in apoptotic insect SL-1 cells induced by Syngrapha falcifera multiple nuclear polyhedrosis virus (SfaMNPV) are reported in this paper. By using Rhodamine 123 as a fluorescent labeling probe, flow cytometry analysis and confocal laser scanning microscope observation we observed that the mitochondrial transmembrane potential (△Ψm) began to decrease in SL-1 cells at 4 h post infection and △Ψm reduced continuously with the extension of virus infection. Western blotting indicated that the Bcl-2 level in the mitochondria gradually declined and was down- regulated. Cells undergoing apoptosis were found to have an elevation of cytochrome c in the cytosol and a corresponding decrease in the mitochondria, which indicated that cytochrome c was released from mitochondria into cytosol. These results suggest that mitochondrion-mediated apoptotic signal transduction pathway exists in apoptotic insect cell induced by SfaMNPV. Cytosolic free calcium ([Ca2+]i) concentration rapidly increased after SfaMNPV infection and the elevated calcium was tested to come partly from extracelllular calcium ion influx. Flow cytometry analysis indicated that the apoptosis in SL-1 cells was not influenced by established cytosolic calcium clamped conditions and the EGTA inhibiting calcium influx. Therefore, neither the elevation of cytosolic calcium ion nor extracellular calcium entry was the inducing factor of apoptosis, which hinted that the depletion of ER Ca2+ store contributed to SL-1 cell apoptosis induced by SfaMNPV.

  18. Modification and secretion of human interleukin 2 produced in insect cells by a baculovirus expression vector.

    OpenAIRE

    Smith, G.E.; Ju, G; Ericson, B L; Moschera, J; Lahm, H W; Chizzonite, R; Summers, M D

    1985-01-01

    A cDNA coding for human interleukin 2 (IL-2) was inserted into the genome of Autographa californica nuclear polyhedrosis virus adjacent to the polyhedrin promoter. Cells infected with recombinant virus produced high levels of Mr 15,500 IL-2 polypeptide, the majority of which was secreted into the culture medium during infection. The recombinant IL-2 was able to stimulate the growth of an IL-2-dependent cell line. The N-terminal amino acid sequence of the insect-derived IL-2 was identical to t...

  19. Proteomics of the 26S proteasome in Spodoptera frugiperda cells infected with the nucleopolyhedrovirus, AcMNPV.

    Science.gov (United States)

    Lyupina, Yulia V; Zatsepina, Olga G; Serebryakova, Marina V; Erokhov, Pavel A; Abaturova, Svetlana B; Kravchuk, Oksana I; Orlova, Olga V; Beljelarskaya, Svetlana N; Lavrov, Andrey I; Sokolova, Olga S; Mikhailov, Victor S

    2016-06-01

    Baculoviruses are large DNA viruses that infect insect species such as Lepidoptera and are used in biotechnology for protein production and in agriculture as insecticides against crop pests. Baculoviruses require activity of host proteasomes for efficient reproduction, but how they control the cellular proteome and interact with the ubiquitin proteasome system (UPS) of infected cells remains unknown. In this report, we analyzed possible changes in the subunit composition of 26S proteasomes of the fall armyworm, Spodoptera frugiperda (Sf9), cells in the course of infection with the Autographa californica multiple nucleopolyhedrovirus (AcMNPV). 26S proteasomes were purified from Sf9 cells by an immune affinity method and subjected to 2D gel electrophoresis followed by MALDI-TOF mass spectrometry and Mascot search in bioinformatics databases. A total of 34 homologues of 26S proteasome subunits of eukaryotic species were identified including 14 subunits of the 20S core particle (7 α and 7 β subunits) and 20 subunits of the 19S regulatory particle (RP). The RP contained homologues of 11 of RPN-type and 6 of RPT-type subunits, 2 deubiquitinating enzymes (UCH-14/UBP6 and UCH-L5/UCH37), and thioredoxin. Similar 2D-gel maps of 26S proteasomes purified from uninfected and AcMNPV-infected cells at 48hpi confirmed the structural integrity of the 26S proteasome in insect cells during baculovirus infection. However, subtle changes in minor forms of some proteasome subunits were detected. A portion of the α5(zeta) cellular pool that presumably was not associated with the proteasome underwent partial proteolysis at a late stage in infection.

  20. Proteomics of the 26S proteasome in Spodoptera frugiperda cells infected with the nucleopolyhedrovirus, AcMNPV.

    Science.gov (United States)

    Lyupina, Yulia V; Zatsepina, Olga G; Serebryakova, Marina V; Erokhov, Pavel A; Abaturova, Svetlana B; Kravchuk, Oksana I; Orlova, Olga V; Beljelarskaya, Svetlana N; Lavrov, Andrey I; Sokolova, Olga S; Mikhailov, Victor S

    2016-06-01

    Baculoviruses are large DNA viruses that infect insect species such as Lepidoptera and are used in biotechnology for protein production and in agriculture as insecticides against crop pests. Baculoviruses require activity of host proteasomes for efficient reproduction, but how they control the cellular proteome and interact with the ubiquitin proteasome system (UPS) of infected cells remains unknown. In this report, we analyzed possible changes in the subunit composition of 26S proteasomes of the fall armyworm, Spodoptera frugiperda (Sf9), cells in the course of infection with the Autographa californica multiple nucleopolyhedrovirus (AcMNPV). 26S proteasomes were purified from Sf9 cells by an immune affinity method and subjected to 2D gel electrophoresis followed by MALDI-TOF mass spectrometry and Mascot search in bioinformatics databases. A total of 34 homologues of 26S proteasome subunits of eukaryotic species were identified including 14 subunits of the 20S core particle (7 α and 7 β subunits) and 20 subunits of the 19S regulatory particle (RP). The RP contained homologues of 11 of RPN-type and 6 of RPT-type subunits, 2 deubiquitinating enzymes (UCH-14/UBP6 and UCH-L5/UCH37), and thioredoxin. Similar 2D-gel maps of 26S proteasomes purified from uninfected and AcMNPV-infected cells at 48hpi confirmed the structural integrity of the 26S proteasome in insect cells during baculovirus infection. However, subtle changes in minor forms of some proteasome subunits were detected. A portion of the α5(zeta) cellular pool that presumably was not associated with the proteasome underwent partial proteolysis at a late stage in infection. PMID:26945516

  1. Manipulation of host plant cells and tissues by gall-inducing insects and adaptive strategies used by different feeding guilds.

    Science.gov (United States)

    Oliveira, D C; Isaias, R M S; Fernandes, G W; Ferreira, B G; Carneiro, R G S; Fuzaro, L

    2016-01-01

    Biologists who study insect-induced plant galls are faced with the overwhelming diversity of plant forms and insect species. A challenge is to find common themes amidst this diversity. We discuss common themes that have emerged from our cytological and histochemical studies of diverse neotropical insect-induced galls. Gall initiation begins with recognition of reactive plant tissues by gall inducers, with subsequent feeding and/or oviposition triggering a cascade of events. Besides, to induce the gall structure insects have to synchronize their life cycle with plant host phenology. We predict that reactive oxygen species (ROS) play a role in gall induction, development and histochemical gradient formation. Controlled levels of ROS mediate the accumulation of (poly)phenols, and phytohormones (such as auxin) at gall sites, which contributes to the new cell developmental pathways and biochemical alterations that lead to gall formation. The classical idea of an insect-induced gall is a chamber lined with a nutritive tissue that is occupied by an insect that directly harvests nutrients from nutritive cells via its mouthparts, which function mechanically and/or as a delivery system for salivary secretions. By studying diverse gall-inducing insects we have discovered that insects with needle-like sucking mouthparts may also induce a nutritive tissue, whose nutrients are indirectly harvested as the gall-inducing insects feeds on adjacent vascular tissues. Activity of carbohydrate-related enzymes across diverse galls corroborates this hypothesis. Our research points to the importance of cytological and histochemical studies for elucidating mechanisms of induced susceptibility and induced resistance. PMID:26620152

  2. Manipulation of host plant cells and tissues by gall-inducing insects and adaptive strategies used by different feeding guilds.

    Science.gov (United States)

    Oliveira, D C; Isaias, R M S; Fernandes, G W; Ferreira, B G; Carneiro, R G S; Fuzaro, L

    2016-01-01

    Biologists who study insect-induced plant galls are faced with the overwhelming diversity of plant forms and insect species. A challenge is to find common themes amidst this diversity. We discuss common themes that have emerged from our cytological and histochemical studies of diverse neotropical insect-induced galls. Gall initiation begins with recognition of reactive plant tissues by gall inducers, with subsequent feeding and/or oviposition triggering a cascade of events. Besides, to induce the gall structure insects have to synchronize their life cycle with plant host phenology. We predict that reactive oxygen species (ROS) play a role in gall induction, development and histochemical gradient formation. Controlled levels of ROS mediate the accumulation of (poly)phenols, and phytohormones (such as auxin) at gall sites, which contributes to the new cell developmental pathways and biochemical alterations that lead to gall formation. The classical idea of an insect-induced gall is a chamber lined with a nutritive tissue that is occupied by an insect that directly harvests nutrients from nutritive cells via its mouthparts, which function mechanically and/or as a delivery system for salivary secretions. By studying diverse gall-inducing insects we have discovered that insects with needle-like sucking mouthparts may also induce a nutritive tissue, whose nutrients are indirectly harvested as the gall-inducing insects feeds on adjacent vascular tissues. Activity of carbohydrate-related enzymes across diverse galls corroborates this hypothesis. Our research points to the importance of cytological and histochemical studies for elucidating mechanisms of induced susceptibility and induced resistance.

  3. Expression of Hantaan virus 26 Kd fragment of nucleocapsid protein in insect cells and prelimimary study on its immunogenicity

    Institute of Scientific and Technical Information of China (English)

    罗雯; 张芳琳; 阎岩; 吴兴安; 刘勇; 白文涛; 王海涛; 徐志凯

    2003-01-01

    Objective: To express the 26 kD fragment of Hantaan virus nucleocapsid protein that contains the major antigenic epitopes in insect cells, and make a preliminary analysis of its immunological characteristics. Methods: The recombinant baculovirus bac-S0.7 with the 700 bp fragment of S gene 5' terminal of Hantaan virus was constructed, and the antigenicity of the expression product was tested. Mice were injected with Sf9 cells infected by the recombinant baculovirus. The humoral and cellular immunological effects were identified by indirect immunofluorescence assay, micro-cell culture neutralization test and T lymphocytes stimulation test. Results: Immunized by bac-S0.7 infecting insect cells, specific antibody with the highest titer of 1∶1 600 was observed. The stimulation indexes of splenocytes of immunized mice to nucleocapsid protein of Hantaan virus was higher than the negative control. Conclusion: The expression product of S0.7 gene fragment in insect cells is immunogenic.

  4. Cell-Based Odorant Sensor Array for Odor Discrimination Based on Insect Odorant Receptors.

    Science.gov (United States)

    Termtanasombat, Maneerat; Mitsuno, Hidefumi; Misawa, Nobuo; Yamahira, Shinya; Sakurai, Takeshi; Yamaguchi, Satoshi; Nagamune, Teruyuki; Kanzaki, Ryohei

    2016-07-01

    The olfactory system of living organisms can accurately discriminate numerous odors by recognizing the pattern of activation of several odorant receptors (ORs). Thus, development of an odorant sensor array based on multiple ORs presents the possibility of mimicking biological odor discrimination mechanisms. Recently, we developed novel odorant sensor elements with high sensitivity and selectivity based on insect OR-expressing Sf21 cells that respond to target odorants by displaying increased fluorescence intensity. Here we introduce the development of an odorant sensor array composed of several Sf21 cell lines expressing different ORs. In this study, an array pattern of four cell lines expressing Or13a, Or56a, BmOR1, and BmOR3 was successfully created using a patterned polydimethylsiloxane film template and cell-immobilizing reagents, termed biocompatible anchor for membrane (BAM). We demonstrated that BAM could create a clear pattern of Sf21 sensor cells without impacting their odorant-sensing performance. Our sensor array showed odorant-specific response patterns toward both odorant mixtures and single odorant stimuli, allowing us to visualize the presence of 1-octen-3-ol, geosmin, bombykol, and bombykal as an increased fluorescence intensity in the region of Or13a, Or56a, BmOR1, and BmOR3 cell lines, respectively. Therefore, we successfully developed a new methodology for creating a cell-based odorant sensor array that enables us to discriminate multiple target odorants. Our method might be expanded into the development of an odorant sensor capable of detecting a large range of environmental odorants that might become a promising tool used in various applications including the study of insect semiochemicals and food contamination.

  5. Production of CCHF Virus-Like Particle by a Baculovirus-Insect Cell Expression System

    Institute of Scientific and Technical Information of China (English)

    Zhao-rui Zhou; Man-li Wang; Fei Deng; Tian-xian Li; Zhi-hong Hu; Hua-fin Wang

    2011-01-01

    Crimean-Congo Haemorrhagic Fever Virus(CCHFV)is a tick-born virus of the Nairovirus genus within the Bunyaviridae family,which is widespread and causes,high fatality. The nucleocapsid of CCHFV is comprised of N proteins that are encoded by the S segment. In this research,the N protein of CCHFV was expressed in insect cells using a recombinant baculovirus. Under an electron microscope,Virus-Like Particles (VLPs)with various size and morphology were observed in cytoplasmic vesicles in the infected cells.Sucrose-gradient purification of the cell lysate indicated that the VLPs were mainly located in the upper fraction after ultracentrifugation,which was confirmed by Western blot analysis and immuno-electron microscopy(IEM).

  6. The silk protein, sericin, protects against cell death caused by acute serum deprivation in insect cell culture.

    Science.gov (United States)

    Takahashi, Masakazu; Tsujimoto, Kazuhisa; Yamada, Hideyuki; Takagi, Hiroshi; Nakamori, Shigeru

    2003-11-01

    Sericin is the silk protein that covers fibroin fibers and functions as a 'glue' in the cocoons of silkworms, and its most abundant component, Ser1, contains repeats of Ser- and Thr-rich 38 amino acid residues. The viability of Sf9 insect cells was 20, 57 and 49% on the fifth day and 41, 91 and 70% on the ninth day after serum deprivation in the presence of no additives, 3000 microg sericin hydrolysate and 350 microg SerD (the peptide containing the two repetitive units) ml(-1), respectively. Thus, the sericin samples were useful in preventing cell death and promoting cellular growth after acute serum deprivation. PMID:14677702

  7. Enhanced protein expression in the baculovirus/insect cell system using engineered SUMO fusions.

    Science.gov (United States)

    Liu, Li; Spurrier, Joshua; Butt, Tauseef R; Strickler, James E

    2008-11-01

    Recombinant protein expression in insect cells varies greatly from protein to protein. A fusion tag that is not only a tool for detection and purification, but also enhances expression and/or solubility would greatly facilitate both structure/function studies and therapeutic protein production. We have shown that fusion of SUMO (small ubiquitin-related modifier) to several test proteins leads to enhanced expression levels in Escherichia coli. In eukaryotic expression systems, however, the SUMO tag could be cleaved by endogenous desumoylase. In order to adapt SUMO-fusion technology to these systems, we have developed an alternative SUMO-derived tag, designated SUMOstar, which is not processed by native SUMO proteases. In the present study, we tested the SUMOstar tag in a baculovirus/insect cell system with several proteins, i.e. mouse UBP43, human tryptase beta II, USP4, USP15, and GFP. Our results demonstrate that fusion to SUMOstar enhanced protein expression levels at least 4-fold compared to either the native or His(6)-tagged proteins. We isolated active SUMOstar tagged UBP43, USP4, USP15, and GFP. Tryptase was active following cleavage with a SUMOstar specific protease. The SUMOstar system will make significant impact in difficult-to-express proteins and especially to those proteins that require the native N-terminal residue for function.

  8. Immunogenicity of empty capsids of porcine circovius type 2 produced in insect cells.

    Science.gov (United States)

    Fan, H; Ju, C; Tong, T; Huang, H; Lv, J; Chen, H

    2007-05-01

    Porcine circovirus type 2 (PCV2), a single-stranded DNA virus, is associated with postweaning multisystemic wasting syndrome (PMWS). ORF2 protein (capsid) of PCV2 was recently demonstrated to be a major immunogenable to induce protection in pigs with a prime-boost protocol. In this study, the ORF2 gene of PCV2 was expressed in insect cells. The product self-assembled into particles that were structurally and antigenically indistinguishable from regular PCV2 capsids. To evaluated the immunogenicity of these virus-like particles, PCV2-free piglets were vaccinated with the crude lysate from recombinant baculovirus (Ac.ORF2)-infected insect cells, at doses of 0.1 ml (10(6) cells), 0.5 mL (5 x 10(6) cells) or 1.0 ml (10(7) cells). The immune response was monitored by an indirect enzyme-linked immunosorbent assay (ELISA) for PCV2 antibody and lymphocyte proliferation assay. The ELISA results indicated that primary immune response was elicited with 0.5 ml or 1.0 ml of crude lysate from Ac.ORF2. After boost immunization, relatively higher levels of PCV2 antibody were elicited in 0.5-ml or 1.0-ml vaccinated groups, compared to the 0.1-ml group. In addition, higher PCV2 specific lymphocyte proliferation response was developed in piglets vaccinated with 0.5 ml or 1.0 ml of crude lysate, especially in those vaccinated with with 1.0 ml of crude lysate. Thus, the expressed ORF2 protein has significant potential as a subunit vaccine against PCV2 infection. PMID:17225085

  9. Expression and Purification of E2 Glycoprotein from Insect Cells (Sf9) for Use in Serology.

    Science.gov (United States)

    Chua, Chong Long; Sam, I-Ching; Chan, Yoke Fun

    2016-01-01

    Chikungunya virus (CHIKV) is a mosquito-borne arbovirus which poses a major threat to global public health. Definitive CHIKV diagnosis is crucial, especially in distinguishing the disease from dengue virus, which co-circulates in endemic areas and shares the same mosquito vectors. Laboratory diagnosis is mainly based on serological or molecular approaches. The E2 glycoprotein is a good candidate for serological diagnosis since it is the immunodominant antigen during the course of infection, and reacts with seropositive CHIKV sera. In this chapter, we describe the generation of stable clone Sf9 (Spodoptera frugiperda) cells expressing secreted, soluble, and native recombinant CHIKV E2 glycoprotein. We use direct plasmid expression in insect cells, rather than the traditional technique of generating recombinant baculovirus. This recombinant protein is useful for serological diagnosis of CHIKV infection. PMID:27233260

  10. On-line near infrared bioreactor monitoring of cell density and concentrations of glucose and lactate during insect cell cultivation.

    Science.gov (United States)

    Qiu, Jiang; Arnold, Mark A; Murhammer, David W

    2014-03-10

    Near infrared spectroscopy is demonstrated as a suitable method for monitoring real time cell density and concentrations of glucose and lactate during insect cell cultivation. The utility of this approach is illustrated during the cultivation of Trichoplusia ni BTI-Tn-5B1-4 insect cells in a stirred-tank bioreactor. On-line near infrared measurements are made by passing unaltered culture medium through an autoclavable near infrared flow-through sample cell during the cultivation process. Single-beam near infrared spectra were collected over the combination spectral range (5000-4000cm(-1)) through a 1.5mm path length sample. Cell density calibration model was established by uni-variable linear regressions with measured mean absorbance values of on-line spectra collected during a cultivation run. Calibration models are generated for glucose and lactate by regression analysis of both off line and on line spectra collected during a series of pre-measurement cultivation runs. Analyte-specific calibration models are generated by using a combination of spectra from both natural, unaltered samples and samples spiked with known levels of glucose and lactate. Spiked samples are used to destroy concentration correlations between solutes, thereby enhancing the selectivity of the calibration models. Absorbance spectra are used to build partial least squares calibration models for glucose and lactate. The calibration model for cell density corresponds to a univariate linear regression calibration model based on the mean absorbance between 4750 and 4250cm(-1). The standard errors of prediction are 1.54mM, 0.83mM, and 0.38×10(6)cells/mL for the glucose, lactate, and cell density models, respectively.

  11. Expression of rice gall dwarf virus outer coat protein gene (S8) in insect cells.

    Science.gov (United States)

    Fan, Guo-cheng; Gao, Fang-luan; Wei, Tai-yun; Huang, Mei-ying; Xie, Li-yan; Wu, Zu-jian; Lin, Qi-ying; Xie, Lian-hui

    2010-12-01

    To obtain the P8 protein of Rice gall dwarf virus (RGDV) with biological activity, its outer coat protein gene S8 was expressed in Spodoptera frugiperda (Sf9) insect cells using the baculovirus expression system. The S8 gene was subcloned into the pFastBac™1 vector, to produce the recombinant baculovirus transfer vector pFB-S8. After transformation, pFB-S8 was introduced into the competent cells (E. coli DH10Bac) containing a shuttle vector, Bacmid, generating the recombinant bacmid rbpFB-S8. After being infected by recombinant baculovirus rvpFB-S8 at different multiplicities of infection, Sf9 cells were collected at different times and analyzed by SDS-PAGE, Western blotting and immunofluorescence microscopy. The expression level of the P8 protein was highest between 48-72 h after transfection of Sf9 cells. Immunofluorescence microscopy showed that P8 protein of RGDV formed punctate structures in the cytoplasm of Sf9 cells.

  12. Observing Insects.

    Science.gov (United States)

    Arbel, Ilil

    1991-01-01

    Describes how to observe and study the fascinating world of insects in public parks, backyards, and gardens. Discusses the activities and habits of several common insects. Includes addresses for sources of beneficial insects, seeds, and plants. (nine references) (JJK)

  13. Production of Chikungunya Virus-Like Particles and Subunit Vaccines in Insect Cells.

    Science.gov (United States)

    Metz, Stefan W; Pijlman, Gorben P

    2016-01-01

    Chikungunya virus is a reemerging human pathogen that causes debilitating arthritic disease in humans. Like dengue and Zika virus, CHIKV is transmitted by Aedes mosquitoes in an epidemic urban cycle, and is now rapidly spreading through the Americas since its introduction in the Caribbean in late 2013. There are no licensed vaccines or antiviral drugs available, and only a few vaccine candidates have passed Phase I human clinical trials. Using recombinant baculovirus expression technology, we have generated CHIKV glycoprotein subunit and virus-like particle (VLP) vaccines that are amenable to large scale production in insect cells. These vaccines, in particular the VLPs, have shown high immunogenicity and protection against CHIKV infection in different animal models of CHIKV-induced disease. Here, we describe the production, purification, and characterization of these potent CHIKV vaccine candidates. PMID:27233282

  14. Two isoforms of trimming glucosidase II exist in mammalian tissues and cell lines but not in yeast and insect cells.

    Science.gov (United States)

    Ziak, M; Meier, M; Etter, K S; Roth, J

    2001-01-12

    We previously cloned glucosidase II and provided in vivo evidence for its involvement in protein folding quality control. DNA-sequencing of different clones demonstrated the existence of two isoforms of glucosidase II which differed by 66 nucleotides due to alternative splicing. The existence of two enzyme isoforms in various organs of pig and rat as well as human, bovine, rat, and mouse cell lines could be demonstrated by RT-PCR and Western blotting. Furthermore, the two isoforms of glucosidase II could be detected in embryonic and postnatal rat kidney and liver. In yeast, Saccharomyces cerevisiae, and in insects, Drosophila S2 cells, only one isoforms of the enzyme was detectable. The ubiquitous occurrence of the two glucosidase II isoforms in mammalian tissues and cell lines might be indicative of a special function of each isoform.

  15. New model for the genesis and maturation of viroplasms induced by fijiviruses in insect vector cells.

    Science.gov (United States)

    Mao, Qianzhuo; Zheng, Shenglan; Han, Qingmei; Chen, Hongyan; Ma, Yuanyuan; Jia, Dongsheng; Chen, Qian; Wei, Taiyun

    2013-06-01

    Plant reoviruses are thought to replicate and assemble within cytoplasmic, nonmembranous structures called viroplasms. Here, we established continuous cell cultures of the white-backed planthopper (Sogatella furcifera Horváth) to investigate the mechanisms for the genesis and maturation of the viroplasm induced by Southern rice black-streaked dwarf virus (SRBSDV), a fijivirus in the family Reoviridae, during infection of its insect vector. Electron and confocal microscopy revealed that the viroplasm consisted of a granular region, where viral RNAs and nonstructural proteins P6 and P9-1 accumulated, and a filamentous region, where viral RNAs, progeny cores, viral particles, as well as nonstructural proteins P5 and P6 accumulated. Our results suggested that the filamentous viroplasm matrix was the site for the assembly of progeny virions. Because viral RNAs were produced by assembled core particles within the filamentous viroplasm matrix, we propose that these viral RNAs might be transported to the granular viroplasm matrix. P5 formed filamentous inclusions and P9-1 formed granular inclusions in the absence of viral infection, suggesting that the filamentous and granular viroplasm matrices were formed primarily by P5 and P9-1, respectively. P6 was apparently recruited in the whole viroplasm matrix by direct interaction with P9-1 and P5. Thus, the present results suggested that P5, P6, and P9-1 are collectively required for the genesis and maturation of the filamentous and granular viroplasm matrix induced by SRBSDV infection. Based on these results, we propose a new model to explain the genesis and maturation of the viroplasms induced by fijiviruses in insect vector cells.

  16. A novel method to study insect olfactory receptor function using HEK293 cells.

    Science.gov (United States)

    Corcoran, Jacob A; Jordan, Melissa D; Carraher, Colm; Newcomb, Richard D

    2014-11-01

    The development of rapid and reliable assays to characterize insect odorant receptors (ORs) and pheromone receptors (PRs) remains a challenge for the field. Typically ORs and PRs are functionally characterized either in vivo in transgenic Drosophila or in vitro through expression in Xenopus oocytes. While these approaches have succeeded, they are not well suited for high-throughput screening campaigns, primarily due to inherent characteristics that limit their ability to screen large quantities of compounds in a short period of time. The development of a practical, robust and consistent in vitro assay for functional studies on ORs and PRs would allow for high-throughput screening for ligands, as well as for compounds that could be used as novel olfactory-based pest management tools. Here we describe a novel method of utilizing human embryonic kidney cells (HEK293) transfected with inducible receptor constructs for the functional characterization of ORs in 96-well plates using a fluorescent spectrophotometer. Using EposOrco and EposOR3 from the pest moth, Epiphyas postvittana as an example, we generated HEK293 cell lines with robust and consistent responses to ligands in functional assays. Single-cell sorting of cell lines by FACS facilitated the selection of isogenic cell lines with maximal responses, and the addition of epitope tags on the N-termini allowed the detection of recombinant proteins in homogenates by western blot and in cells by immunocytochemistry. We thoroughly describe the methods used to generate these OR-expressing cell lines, demonstrating that they have all the necessary features required for use in high-throughput screening platforms.

  17. Recombinant GDNF: Tetanus toxin fragment C fusion protein produced from insect cells

    International Nuclear Information System (INIS)

    Glial cell line-derived neurotrophic factor (GDNF) has potent survival-promoting effects on CNS motor neurons in experimental animals. Its therapeutic efficacy in humans, however, may have been limited by poor bioavailability to the brain and spinal cord. With a view toward improving delivery of GDNF to CNS motor neurons in vivo, we generated a recombinant fusion protein comprised of rat GDNF linked to the non-toxic, neuron-binding fragment of tetanus toxin. Recombinant GDNF:TTC produced from insect cells was a soluble homodimer like wild-type GDNF and was bi-functional with respect to GDNF and TTC activity. Like recombinant rat GDNF, the fusion protein increased levels of immunoreactive phosphoAkt in treated NB41A3-hGFRα-1 neuroblastoma cells. Like TTC, GDNF:TTC bound to immobilized ganglioside GT1b in vitro with high affinity and selectivity. These results support further testing of recombinant GDNF:TTC as a non-viral vector to improve delivery of GDNF to brain and spinal cord in vivo.

  18. Recombinant GDNF: Tetanus toxin fragment C fusion protein produced from insect cells

    Energy Technology Data Exchange (ETDEWEB)

    Li, Jianhong; Chian, Ru-Ju; Ay, Ilknur; Celia, Samuel A.; Kashi, Brenda B.; Tamrazian, Eric; Matthews, Jonathan C. [Cecil B. Day Laboratory for Neuromuscular Research, Department of Neurology, Massachusetts General Hospital, Charlestown, MA 02129 (United States); Remington, Mary P. [Research Service, Baltimore Veterans Affairs Medical Center, Baltimore, MD 21201 (United States); Pepinsky, R. Blake [BiogenIdec, Inc., 14 Cambridge Center, Cambridge, MA 02142 (United States); Fishman, Paul S. [Research Service, Baltimore Veterans Affairs Medical Center, Baltimore, MD 21201 (United States); Department of Neurology, University of Maryland School of Medicine, Baltimore, MD 21201 (United States); Brown, Robert H. [Cecil B. Day Laboratory for Neuromuscular Research, Department of Neurology, Massachusetts General Hospital, Charlestown, MA 02129 (United States); Francis, Jonathan W., E-mail: jwfrancisby@gmail.com [Cecil B. Day Laboratory for Neuromuscular Research, Department of Neurology, Massachusetts General Hospital, Charlestown, MA 02129 (United States)

    2009-07-31

    Glial cell line-derived neurotrophic factor (GDNF) has potent survival-promoting effects on CNS motor neurons in experimental animals. Its therapeutic efficacy in humans, however, may have been limited by poor bioavailability to the brain and spinal cord. With a view toward improving delivery of GDNF to CNS motor neurons in vivo, we generated a recombinant fusion protein comprised of rat GDNF linked to the non-toxic, neuron-binding fragment of tetanus toxin. Recombinant GDNF:TTC produced from insect cells was a soluble homodimer like wild-type GDNF and was bi-functional with respect to GDNF and TTC activity. Like recombinant rat GDNF, the fusion protein increased levels of immunoreactive phosphoAkt in treated NB41A3-hGFR{alpha}-1 neuroblastoma cells. Like TTC, GDNF:TTC bound to immobilized ganglioside GT1b in vitro with high affinity and selectivity. These results support further testing of recombinant GDNF:TTC as a non-viral vector to improve delivery of GDNF to brain and spinal cord in vivo.

  19. The Role of Cytochrome c on Apoptosis Induced by Anagrapha falcifera Multiple Nuclear Polyhedrosis Virus in Insect Spodoptera litura Cells

    OpenAIRE

    Kaiyu Liu; Duanyang Shu; Na Song; Zhongchao Gai; Yuan Yuan; Juan Li; Min Li; Shuying Guo; Jianxin Peng; Huazhu Hong

    2012-01-01

    There are conflicting reports on the role of cytochrome c during insect apoptosis. Our previous studies have showed that cytochrome c released from the mitochondria was an early event by western blot analysis and caspase-3 activation was closely related to cytochrome c release during apoptosis induced by baculovirus in Spodoptera litura cells (Sl-1 cell line). In the present study, alteration in mitochondrial morphology was observed by transmission electron microscopy, and cytochrome c releas...

  20. Use of a stationary bed reactor and serum-free medium for the production of recombinant proteins in insect cells.

    Science.gov (United States)

    Kompier, R; Kislev, N; Segal, I; Kadouri, A

    1991-10-01

    Insect cells (Spodoptera frugiperda) have been cultured in a stationary bed reactor, packed with a fibrous polyester carrier. When the bioreactor was perfused with serum-supplemented medium, a cell density of 6 x 10(6) cells ml-1 packed carrier was reached. Scanning electron microscopy investigations have shown that the insect cells grew along the three-dimensionally oriented fibers of the Fibra-cel carrier. After infection of the logarithmically growing cells with a recombinant baculovirus (Autographa californica) containing the gene coding for beta-galactosidase, the medium in the bioreactor was changed to serum-free medium. At day 13 postinfection (p.i.), a beta-galactosidase level of 320 microgram ml-1 and, at day 17 p.i., a virus titer of 2.1 x 10(8) TCID50 units ml-1 (day 17 p.i.) were reached. In another bioreactor, operated in a similar way but with serum-containing medium, a beta-galactosidase concentration of 360 microgram ml-1 and a virus titer of 2.3 x 10(8) TCID50 units ml-1 were obtained. These results indicate the potential use of this production system for the production of recombinant protein and baculovirus in insect cells. PMID:1367637

  1. Nanofibers and nanoparticles from the insect-capturing adhesive of the Sundew (Drosera for cell attachment

    Directory of Open Access Journals (Sweden)

    Zhang Mingjun

    2010-08-01

    Full Text Available Abstract Background The search for naturally occurring nanocomposites with diverse properties for tissue engineering has been a major interest for biomaterial research. In this study, we investigated a nanofiber and nanoparticle based nanocomposite secreted from an insect-capturing plant, the Sundew, for cell attachment. The adhesive nanocomposite has demonstrated high biocompatibility and is ready to be used with minimal preparation. Results Atomic force microscopy (AFM conducted on the adhesive from three species of Sundew found that a network of nanofibers and nanoparticles with various sizes existed independent of the coated surface. AFM and light microscopy confirmed that the pattern of nanofibers corresponded to Alcian Blue staining for polysaccharide. Transmission electron microscopy identified a low abundance of nanoparticles in different pattern form AFM observations. In addition, energy-dispersive X-ray spectroscopy revealed the presence of Ca, Mg, and Cl, common components of biological salts. Study of the material properties of the adhesive yielded high viscoelasticity from the liquid adhesive, with reduced elasticity observed in the dried adhesive. The ability of PC12 neuron-like cells to attach and grow on the network of nanofibers created from the dried adhesive demonstrated the potential of this network to be used in tissue engineering, and other biomedical applications. Conclusions This discovery demonstrates how a naturally occurring nanofiber and nanoparticle based nanocomposite from the adhesive of Sundew can be used for tissue engineering, and opens the possibility for further examination of natural plant adhesives for biomedical applications.

  2. Human Papillomavirus Type16- L1 VLP Production in Insect Cells

    Directory of Open Access Journals (Sweden)

    Asghar Abdoli

    2013-08-01

    Full Text Available   Objective(s:  Infection by high-risk papillomavirus is regarded as the major risk factor in the development of cervical cancer. Recombinant DNA technology allows expression of the L1 major capsid protein of HPV in different expression systems, which has intrinsic capacity to self-assemble into viral-like particles (VLP. VLPS are non-infectious, highly immunogenic and can elicit neutralizing antibodies. VLP-based HPV vaccines can prevent persistent HPV infections and cervical cancer. In this study recombinant HPV-16 L1 protein was produced in Sf9 insect cells and VLP formation was confirmed. Materials and Methods: Complete HPV-16 L1 gene was inserted into pFast HTa plasmid and transformed into DH10BAC Escherichia coli containing bacmid and helper plasmid. The recombinant Bacmid colonies turned to white and non-recombinant colonies harboring L1 gene remained blue in the presence of X-gal and IPTG in colony selection strategy. To confirm the recombinant bacmid production, PCR was applied using specific L1 primers. To produce recombinant baculovirus, the recombinant bacmid DNA was extracted and transfected into Sf9 cells using Cellfectin. The expression of L1 in Sf9 cells was identified through SDS-PAGE and western blot analysis using specific L1 monoclonal antibody. Self-assembled HPV16L-VLPs in Sf9 cells was confirmed by electron microscopy. Results:The recombinant protein L1 was predominantly ~60 KD in SDS-PAGE with distinct immunoreactivity in western blot analysis and formed VLPS as confirmed by electron microscopy. Conclusion:Application of recombinant baculovirus containing HPV-16 L1 gene will certainly prove to be a constructive tool in production of VLPs for prophylactic vaccine development as well as diagnostic tests.

  3. The role of cytochrome c on apoptosis induced by Anagrapha falcifera multiple nuclear polyhedrosis virus in insect Spodoptera litura cells.

    Directory of Open Access Journals (Sweden)

    Kaiyu Liu

    Full Text Available There are conflicting reports on the role of cytochrome c during insect apoptosis. Our previous studies have showed that cytochrome c released from the mitochondria was an early event by western blot analysis and caspase-3 activation was closely related to cytochrome c release during apoptosis induced by baculovirus in Spodoptera litura cells (Sl-1 cell line. In the present study, alteration in mitochondrial morphology was observed by transmission electron microscopy, and cytochrome c release from mitochondria in apoptotic Sl-1 cells induced with Anagrapha falcifera multiple nuclear polyhedrosis virus (AfMNPV has further been confirmed by immunofluoresence staining protocol, suggesting that structural disruption of mitochondria and the release of cytochrome c are important events during Lepidoptera insect cell apoptosis. We also used Sl-1 cell-free extract system and the technique of RNA interference to further investigate the role of cytochrome c in apoptotic Sl-1 cells induced by AfMNPV. Caspase-3 activity in cell-free extracts supplemented with exogenous cytochrome c was determined and showed an increase with the extension of incubation time. DsRNA-mediated silencing of cytochrome c resulted in the inhibition of apoptosis and protected the cells from AfMNPV-induced cell death. Silencing of expression of cytochrome c had a remarkable effect on pro-caspase-3 and pro-caspase-9 activation and resulted in the reduction of caspase-3 and caspase-9 activity in Sl-1 cells undergoing apoptosis. Caspase-9 inhibitor could inhibit activation of pro-caspase-3, and the inhibition of the function of Apaf-1 with FSBA blocked apoptosis, hinting that Apaf-1 could be involved in Sl-1 cell apoptosis induced by AfMNPV. Taken together, these results strongly demonstrate that cytochrome c plays an important role in apoptotic signaling pathways in Lepidopteran insect cells.

  4. Expression, assembly, and proteolytic processing of Helminthosporium victoriae 190S totivirus capsid protein in insect cells.

    Science.gov (United States)

    Huang, S; Soldevila, A I; Webb, B A; Ghabrial, S A

    1997-07-21

    The dsRNA genome (5.2 kbp) of Helminthosporium victoriae 190S totivirus (Hv190SV) consists of two large overlapping open reading frames (ORFs). The 5' proximal ORF codes for the capsid protein (CP) and the 3' ORF codes for an RNA-dependent RNA polymerase. Although the capsid of Hv190SV is encoded by a single gene, it is composed of two major closely related polypeptides, either p88 and p83 or p88 and p78. Whereas p88 and p83 are phosphoproteins, p78 is nonphosphorylated. Expression of the CP ORF in insect cells generated both p78 and p88 which assembled into virus-like particles. The finding that p78, p83, and p88 share a common N-terminal amino acid sequence is consistent with the determination that N-terminal, but not C-terminal, CP deletions were incompetent for assembly. Evidence was obtained that p78 is derived from p88 via proteolytic cleavage at the C-terminus. Proteolytic processing may play a regulatory role in the virus life cycle since it leads to dephosphorylation of CP and a subsequent decrease in virion transcriptional activity.

  5. SweetBac: a new approach for the production of mammalianised glycoproteins in insect cells.

    Directory of Open Access Journals (Sweden)

    Dieter Palmberger

    Full Text Available Recombinant production of therapeutically active proteins has become a central focus of contemporary life science research. These proteins are often produced in mammalian cells, in order to obtain products with post-translational modifications similar to their natural counterparts. However, in cases where a fast and flexible system for recombinant production of proteins is needed, the use of mammalian cells is limited. The baculoviral insect cell system has proven to be a powerful alternative for the expression of a wide range of recombinant proteins in short time frames. The major drawback of baculoviral systems lies in the inability to perform mammalian-like glycosylation required for the production of therapeutic glycoproteins. In this study we integrated sequences encoding Caenorhabditis elegans N-acetylglucosaminyltransferase II and bovine β1,4-galactosyltransferase I into the backbone of a baculovirus genome. The thereby generated SweetBac virus was subsequently used for the production of the human HIV anti-gp41 antibody 3D6 by integrating heavy and light chain open reading frames into the SweetBac genome. The parallel expression of target genes and glycosyltransferases reduced the yield of secreted antibody. However, the overall expression rate, especially in the recently established Tnao38 cell line, was comparable to that of transient expression in mammalian cells. In order to evaluate the ability of SweetBac to generate mammalian-like N-glycan structures on 3D6 antibody, we performed SDS-PAGE and tested for the presence of terminal galactose using Riccinus communis agglutinin I. The mammalianised variants of 3D6 showed highly specific binding to the lectin, indicating proper functionality. To confirm these results, PNGase A released N-glycans were analyzed by MALDI-TOF-MS and shown to contain structures with mainly one or two terminal galactose residues. Since the presence of specific N-glycans has an impact on antibodies ability to

  6. Large scale production and downstream processing of a recombinant porcine parvovirus vaccine

    NARCIS (Netherlands)

    Maranga, L.; Rueda, P.; Antonis, A.F.G.; Vela, C.; Langeveld, J.P.M.; Casal, J.I.; Carrondo, M.J.T.

    2002-01-01

    Porcine parvovirus (PPV) virus-like particles (VLPs) constitute a potential vaccine for prevention of parvovirus-induced reproductive failure in gilts. Here we report the development of a large scale (25 l) production process for PPV-VLPs with baculovirus-infected insect cells. A low multiplicity of

  7. Characterization of the N-glycans of recombinant bee venom hyaluronidase (Api m 2) expressed in insect cells.

    Science.gov (United States)

    Soldatova, Lyudmila N; Tsai, Chaoming; Dobrovolskaia, Ekaterina; Marković-Housley, Zora; Slater, Jay E

    2007-01-01

    Honeybee venom hyaluronidase (Api m 2) is a major glycoprotein allergen. Previous studies have indicated that recombinant Api m 2 expressed in insect cells has enzyme activity and IgE binding comparable with that of native Api m 2. In contrast, Api m 2 expressed in Escherichia coli does not. In this study, we characterized the carbohydrate side chains of Api m 2 expressed in insect cells, and compared our data with the established carbohydrate structure of native Api m 2. We assessed both the monosaccharide and the oligosaccharide content of recombinant Api m 2 using fluorophore-assisted carbohydrate electrophoresis and HPLC. To identify the amino acid residues at which glycosylation occurs, we digested recombinant Api m 2 with endoproteinase Glu-C and identified the fragments that contained carbohydrate by specific staining. Recombinant Api m 2 expressed in insect cells contains N-acetylglucosamine, mannose, and fucose, as well as trace amounts of glucose and galactose, and the oligosaccharide analysis is consistent with heterogeneous oligosaccharide chains consisting of two to seven monosaccharides. No sialic acid or N-acetylgalactosamine were detected. These results are similar to published data for native Api m 2, although some monosaccharide components appear to be absent in the recombinant protein. Analysis of proteolytic digests indicates that of the four candidate N-glycosylation sites, carbohydrate chains are attached at asparagines 115 and 263. Recombinant Api m 2 expressed in insect cells has enzymic activity and IgE binding comparable with the native protein, and its carbohydrate composition is very similar. PMID:17479607

  8. Transcriptional control of fungal cell cycle and cellular events by Fkh2, a forkhead transcription factor in an insect pathogen

    OpenAIRE

    Wang, Juan-juan; Qiu, Lei; Cai, Qing; Ying, Sheng-Hua; Feng, Ming-Guang

    2015-01-01

    Transcriptional control of the cell cycle by forkhead (Fkh) transcription factors is likely associated with fungal adaptation to host and environment. Here we show that Fkh2, an ortholog of yeast Fkh1/2, orchestrates cell cycle and many cellular events of Beauveria bassiana, a filamentous fungal insect pathogen. Deletion of Fkh2 in B. bassiana resulted in dramatic down-regulation of the cyclin-B gene cluster and hence altered cell cycle (longer G2/M and S, but shorter G0/G1, phases) in unicel...

  9. Expression and enzyme activity determination of human cyclooxygenase-1 and -2 in a baculovirus-insect cell system

    Institute of Scientific and Technical Information of China (English)

    Wei-yu ZHANG; Xin-ning YANG; Dao-zhong JIN; Xing-zu ZHU

    2004-01-01

    AIM: To develop an in vitro intact cell-based assay for screening selective cyclooxygenase inhibitors. METHODS:Human cyclooxygenase-1 (hCOX-1) and cyclooxygenase-2 (hCOX-2) genes were cloned from human monocyte cell line THP-1 cells and expressed in Spodopterafrugiperda (sf9) insect cell line by Bac-to-Bac baculovirus expression systems. Infected sr9 cells were harvested 24 h post-infection (hpi), and distributed to a 24-well plate,preincubated with various nonsteroidal anti-inflammatory drugs, and challenged with 10 mmol/L arachidonic acid;the cyclooxygenase activity was assessed indirectly by prostaglandin E2-specific radioimmunoassay. RESULTS:Polymerase chain reaction detection demonstrated that hCOX-1 and hCOX-2 were transposed to the bacmid.Western blot analysis showed that infected sf9 cells could express hCOX-1 and hCOX-2 proteins. Radioimmunoassay demonstrated that both recombinant proteins functioned well in sf9 cells. CONCLUSION: Human cyclooxygenase-1 and cyclooxygenase-2 were successfully expressed in sf9 insect cell line. It can be utilized for the identification of potent and selective inhibitors of hCOX- 1 and/or hCOX-2.

  10. Head-to-head comparison of three vaccination strategies based on DNA and raw insect-derived recombinant proteins against Leishmania.

    Science.gov (United States)

    Todolí, Felicitat; Rodríguez-Cortés, Alhelí; Núñez, María Del Carmen; Laurenti, Márcia D; Gómez-Sebastián, Silvia; Rodríguez, Fernando; Pérez-Martín, Eva; Escribano, José M; Alberola, Jordi

    2012-01-01

    Parasitic diseases plague billions of people among the poorest, killing millions annually, and causing additional millions of disability-adjusted life years lost. Leishmaniases affect more than 12 million people, with over 350 million people at risk. There is an urgent need for efficacious and cheap vaccines and treatments against visceral leishmaniasis (VL), its most severe form. Several vaccination strategies have been proposed but to date no head-to-head comparison was undertaken to assess which is the best in a clinical model of the disease. We simultaneously assayed three vaccination strategies against VL in the hamster model, using KMPII, TRYP, LACK, and PAPLE22 vaccine candidate antigens. Four groups of hamsters were immunized using the following approaches: 1) raw extracts of baculovirus-infected Trichoplusia ni larvae expressing individually one of the four recombinant proteins (PROT); 2) naked pVAX1 plasmids carrying the four genes individually (DNA); 3) a heterologous prime-boost (HPB) strategy involving DNA followed by PROT (DNA-PROT); and 4) a Control including empty pVAX1 plasmid followed by raw extract of wild-type baculovirus-infected T. ni larvae. Hamsters were challenged with L. infantum promastigotes and maintained for 20 weeks. While PROT vaccine was not protective, DNA vaccination achieved protection in spleen. Only DNA-PROT vaccination induced significant NO production by macrophages, accompanied by a significant parasitological protection in spleen and blood. Thus, the DNA-PROT strategy elicits strong immune responses and high parasitological protection in the clinical model of VL, better than its corresponding naked DNA or protein versions. Furthermore, we show that naked DNA coupled with raw recombinant proteins produced in insect larvae biofactories -the cheapest way of producing DNA-PROT vaccines- is a practical and cost-effective way for potential "off the shelf" supplying vaccines at very low prices for the protection against

  11. Head-to-head comparison of three vaccination strategies based on DNA and raw insect-derived recombinant proteins against Leishmania.

    Directory of Open Access Journals (Sweden)

    Felicitat Todolí

    Full Text Available Parasitic diseases plague billions of people among the poorest, killing millions annually, and causing additional millions of disability-adjusted life years lost. Leishmaniases affect more than 12 million people, with over 350 million people at risk. There is an urgent need for efficacious and cheap vaccines and treatments against visceral leishmaniasis (VL, its most severe form. Several vaccination strategies have been proposed but to date no head-to-head comparison was undertaken to assess which is the best in a clinical model of the disease. We simultaneously assayed three vaccination strategies against VL in the hamster model, using KMPII, TRYP, LACK, and PAPLE22 vaccine candidate antigens. Four groups of hamsters were immunized using the following approaches: 1 raw extracts of baculovirus-infected Trichoplusia ni larvae expressing individually one of the four recombinant proteins (PROT; 2 naked pVAX1 plasmids carrying the four genes individually (DNA; 3 a heterologous prime-boost (HPB strategy involving DNA followed by PROT (DNA-PROT; and 4 a Control including empty pVAX1 plasmid followed by raw extract of wild-type baculovirus-infected T. ni larvae. Hamsters were challenged with L. infantum promastigotes and maintained for 20 weeks. While PROT vaccine was not protective, DNA vaccination achieved protection in spleen. Only DNA-PROT vaccination induced significant NO production by macrophages, accompanied by a significant parasitological protection in spleen and blood. Thus, the DNA-PROT strategy elicits strong immune responses and high parasitological protection in the clinical model of VL, better than its corresponding naked DNA or protein versions. Furthermore, we show that naked DNA coupled with raw recombinant proteins produced in insect larvae biofactories -the cheapest way of producing DNA-PROT vaccines- is a practical and cost-effective way for potential "off the shelf" supplying vaccines at very low prices for the protection against

  12. A sericin-derived peptide protects sf9 insect cells from death caused by acute serum deprivation.

    Science.gov (United States)

    Takahashi, Masakazu; Tsujimoto, Kazuhisa; Kato, Youichi; Yamada, Hideyuki; Takagi, Hiroshi; Nakamori, Shigeru

    2005-07-01

    Sericin is the silk protein enveloping fibroin fibers in cocoons. Sericin hydrolysate protects cultured Sf9 insect cells from death caused by serum deprivation; the activity depends on the repeats of 38 amino acids. A partial peptide from the 38 residues, SGGSSTYGYS, inhibited serum-deprivation death as well. Cell viabilities in the presence of 10% (v/v) foetal calf serum, no additives and 1 mM: SGGSSTYGYS were 96, 12 and 31% on the third day after inoculation, respectively. Aromatic residues seemed to be important because SGGSSTWGWS had the same activity as SGGSSTYGYS but SGGSSTAGAS had no activity. PMID:16091882

  13. Microcarrier culture of lepidopteran cell lines: implications for growth and recombinant protein production.

    Science.gov (United States)

    Ikonomou, Laertis; Drugmand, Jean-Christophe; Bastin, Georges; Schneider, Yves-Jacques; Agathos, Spiros N

    2002-01-01

    Several microcarrier systems were screened with Sf-9 and High-Five cell lines as to their ability to support cell growth and recombinant (beta-galactosidase) protein production. Growth of both cell lines on compact microcarriers, such as Cytodex-1 and glass beads, was minimal, as cells detached easily from the microcarrier surface and grew as single cells in the medium. Cell growth was also problematic on Cytopore-1 and -2 porous microcarriers. Cells remained attached for several days inside the microcarrier pores, but no cell division and proliferation were observed. On the contrary, insect cells grew well in the interior of Fibra-Cel disks mainly as aggregates at points of fiber intersection, reaching final (plateau) densities of about 4 x 10(6) (Sf-9) and 2.7 x 10(6) (High-Five) cells mL(-1) (8 x 10(6) and 5.5 x 10(6) cells per cm(2) of projected disk area, respectively). Their growth was described well by the logistic equation, which takes into account possible inhibition effects. Beta-Galactosidase (beta-gal) production of Sf-9 cells on Fibra-Cel disks (infected at 3.3 x 10(6) cells mL(-1)) was prolonged (192 h), and specific protein production was similar to that of high-density free cell infection. Cultispher-S microcarriers were found to be a very efficient system for the growth of High-Five cells, whereas no growth of Sf-9 cells took place for the same system. Concentrations of about 9 x 10(6) cells mL(-1) were reached within 120 h, with cell growth in both microcarriers and aggregates, appearance of cellular bridges between microcarriers and aggregates, and eventual formation of macroaggregates incorporating several microcarriers. Specific protein productions after beta-gal baculovirus infection at increasing cell concentrations were almost constant, thus leading to elevated volumetric protein production: final beta-gal titers of 946, 1728, and 1484 U mL(-1) were obtained for infection densities of 3.4, 7.2, and 8.9 x 10(6) cells mL(-1), respectively

  14. Microcarrier culture of lepidopteran cell lines: implications for growth and recombinant protein production.

    Science.gov (United States)

    Ikonomou, Laertis; Drugmand, Jean-Christophe; Bastin, Georges; Schneider, Yves-Jacques; Agathos, Spiros N

    2002-01-01

    Several microcarrier systems were screened with Sf-9 and High-Five cell lines as to their ability to support cell growth and recombinant (beta-galactosidase) protein production. Growth of both cell lines on compact microcarriers, such as Cytodex-1 and glass beads, was minimal, as cells detached easily from the microcarrier surface and grew as single cells in the medium. Cell growth was also problematic on Cytopore-1 and -2 porous microcarriers. Cells remained attached for several days inside the microcarrier pores, but no cell division and proliferation were observed. On the contrary, insect cells grew well in the interior of Fibra-Cel disks mainly as aggregates at points of fiber intersection, reaching final (plateau) densities of about 4 x 10(6) (Sf-9) and 2.7 x 10(6) (High-Five) cells mL(-1) (8 x 10(6) and 5.5 x 10(6) cells per cm(2) of projected disk area, respectively). Their growth was described well by the logistic equation, which takes into account possible inhibition effects. Beta-Galactosidase (beta-gal) production of Sf-9 cells on Fibra-Cel disks (infected at 3.3 x 10(6) cells mL(-1)) was prolonged (192 h), and specific protein production was similar to that of high-density free cell infection. Cultispher-S microcarriers were found to be a very efficient system for the growth of High-Five cells, whereas no growth of Sf-9 cells took place for the same system. Concentrations of about 9 x 10(6) cells mL(-1) were reached within 120 h, with cell growth in both microcarriers and aggregates, appearance of cellular bridges between microcarriers and aggregates, and eventual formation of macroaggregates incorporating several microcarriers. Specific protein productions after beta-gal baculovirus infection at increasing cell concentrations were almost constant, thus leading to elevated volumetric protein production: final beta-gal titers of 946, 1728, and 1484 U mL(-1) were obtained for infection densities of 3.4, 7.2, and 8.9 x 10(6) cells mL(-1), respectively.

  15. High-Level Production of a Functional Recombinant Hepatitis B Virus Polymerase in Insect Cells with a Baculovirus Expression System

    Institute of Scientific and Technical Information of China (English)

    WANG Xiaoyan; GAO Linlin; DENG Fei; ZHANG Yanfang; LI Yan; LIN Jusheng

    2007-01-01

    HBV polymerase has intrinsic RNA-dependent reverse transcriptase, DNA-dependent DNA polymerase as well as RNaseH activity. Analysis of HBV polymerase has been hampered for many years due to the inability to express functional enzyme in a recombinant system. To obtain active polymerase at a high level, we have taken advantage of baculovirus expression system. The gene of HBV polymerase was amplified by PCR and cloned into pFastBac Dual to construct the recombinant plasmid pFastbac Dual-pol. The recombinant donor plasmid, pFastbac Dual-pol, was constructed by inserting HBV polymerase gene into EcoRI and PstI sites controlled by polyhedrin promoter. The recombinant donor plasmid was transformed into DH10Bac competent cells for transposition. Recombinant bacmid was constructed by inserting of the mini-Tn7 element from the donor plasmid into the mini-attTn7 attachment site on the bacmid. The recombinant bacmid DNA was isolated and transfected into the Sf9 cells to produce the recombinant virus, and healthy insect Sf9 cells were infected with the recombinant virus containing HBV polymerse gene to express the target protein. HBV polymerse expressed in insect cells was analyzed by SDS-PAGE. PCR results showed recombinant donor plasmid, pFastbac Dual-pol, was constructed successfully. The recombinant hepatitis B virus polymerase was expressed in insect cells at high level. The recombinant hepatitis B virus polymerase should facilitate the analysis of HBV polymerase biological characteristics, allow the investigation for new anti-HBV drugs specifically blocking HBV polymerase.

  16. Recombinant Outer Capsid Glycoprotein (VP7 of Rotavirus Expressed in Insect Cells Induces Neutralizing Antibodies in Rabbits

    Directory of Open Access Journals (Sweden)

    H Keyvani

    2012-04-01

    Full Text Available Background:Rotaviruses cause diarrhea in infants and young children worldwide. Rotavirus outer capsid protein, VP7 is major neutralizing antigen that is important component of subunit vaccine to prevent rotavirus infection.Many efforts have been done to produce recombinant VP7 that maintain native characteristics.We used baculovirus expression system to produce rotavirus VP7 protein and to study its immunogenicity. Methods: Simian rotavirus SA11 full-length VP7 ORF was cloned into a cloning plasmid and then the cloned gene was inserted into the linear DNA of baculovirus Autographa californica Nuclear Polyhedrosis Virus (AcNPV downstream of the polyhedrin promoter by in vitro recombination reactions. The expressed VP7 in the insect cells was recognized by rabbit hyperimmune serum raised against SA11 rotavirus by Immunofluorescence and western blotting assays. Rabbits were immunized subcutaneously by cell extracts expressing VP7 protein. Results: Reactivity with anti-rotavirus antibody suggested that expressed VP7 protein had native antigenic determinants.Injection of recombinant VP7 in rabbits elicited the production of serum antibodies,which were able to recognize VP7 protein from SA11 rotavirus by Western blotting test and neutralized SA11 rotavirus in cell culture.Conclusion: Recombinant outer capsid glycoprotein (VP7 of rotavirus expressed in insect cells induces neutralizing antibodies in rabbits and may be a candidate of rotavirus vaccine.

  17. Distribution and Spectroscopy of Green Fluorescent Protein and Acyl-CoA: Cholesterol Acytransferase in Sf21 Insect Cells

    Science.gov (United States)

    Richmond, R. C.; Mahtani, H.; Lu, X.; Chang, T. Y.; Malak, H.; Rose, M. Franklin (Technical Monitor)

    2001-01-01

    Acyl-CoA: cholesterol acyltransferase (ACAT) is thought to significantly participate in the pathway of cholesterol esterification that underlies the pathology of artherosclerosis. This enzyme is a membrane protein known to be preferentially bound within the endoplasmic reticulum of mammalian cells, from which location it esterifies cholesterol derived from low density lipoprotein. Cultures of insect cells were separately infected with baculovirus containing the gene for green fluroescent protein (GFP) and with baculovirus containing tandem genes for GFP and ACAT. These infected cultures expressed GFP and the fusion protein GCAT, respectively, with maximum expression occurring on the fourth day after infection. Extraction of GFP- and of GCAT-expressing cells with urea and detergent resulted in recovery of fluorescent protein in aqueous solution. Fluorescence spectra at neutral pH were identical for both GFP and GCAT extracts in aqueous solution, indicating unperturbed tertiary structure for the GFP moiety within GCAT. In a cholesterol esterification assay, GCAT demonstrated ACAT activity, but with less efficiency compared to native ACAT. It was hypothesized that the membrane protein ACAT would lead to differences in localization of GCAT compared to GFP within the respective expressing insect cells. The GFP marker directly and also within the fusion protein GCAT was accordingly used as the intracellular probe that was fluorescently analyzed by the new biophotonics technique of hyperspectral imaging. In that technique, fluorescence imaging was obtained from two dimensional arrays of cells, and regions of interest from within those images were then retrospectively analyzed for the emission spectra that comprises the image. Results of hyperspectral imaging of insect cells on day 4 postinfection showed that GCAT was preferentially localized to the cytoplasm of these cells compared to GFP. Furthermore, the emission spectra obtained for the localized GCAT displayed a peak

  18. Insect Allergy.

    Science.gov (United States)

    Lee, Hobart; Halverson, Sara; Mackey, Regina

    2016-09-01

    Insect bites and stings are common. Risk factors are mostly associated with environmental exposure. Most insect bites and stings result in mild, local, allergic reactions. Large local reactions and systemic reactions like anaphylaxis are possible. Common insects that bite or sting include mosquitoes, ticks, flies, fleas, biting midges, bees, and wasps. The diagnosis is made clinically. Identification of the insect should occur when possible. Management is usually supportive. For anaphylaxis, patients should be given epinephrine and transported to the emergency department for further evaluation. Venom immunotherapy (VIT) has several different protocols. VIT is highly effective in reducing systemic reactions and anaphylaxis. PMID:27545732

  19. Chromatin condensation and differential sensitivity of mammalian and insect cells to DNA strand breaks induced by bleomycin

    Energy Technology Data Exchange (ETDEWEB)

    Lopez-Larraza, Daniel M. [IMBICE, C.C. 403, 1900 La Plata (Argentina)]. E-mail: danielop@imbice.org.ar; Padron, Juan [IMBICE, C.C. 403, 1900 La Plata (Argentina); Ronci, Natalia E. [IMBICE, C.C. 403, 1900 La Plata (Argentina); Vidal Rioja, Lidia A. [IMBICE, C.C. 403, 1900 La Plata (Argentina)

    2006-08-30

    Bleomycin (BLM) induces DNA damage in living cells. In this report we analyzed the role of chromatin compactness in the differential response of mosquito (ATC-15) and mammalian (CHO) cells to DNA strand breaks induced by BLM. We used cells unexposed and exposed to sodium butyrate (NaB), which induces chromatin decondensation. By nucleoid sedimentation assay and digestions of nuclei with DNAse I, untreated mosquito cells (no BLM; no NaB) were shown to have more chromatin condensation than untreated CHO cells. By alkaline unwinding ATC-15 cells treated with NaB showed more BLM-induced DNA strand breaks than NaB-untreated CHO cells. The time-course of BLM-induced DNA damage to nuclear DNA was similar for NaB-untreated mammalian and insect cells, but with mosquito cells showing less DNA strand breaks, both at physiological temperatures and at 4 {sup o}C. However, when DNA repair was inhibited by low temperatures and chromatin was decondensed by NaB treatments, differences in BLM-induced DNA damage between these cells lines were no longer observed. In both cell lines, NaB did not affect BLM action on cell growth and viability. On the other hand, the low sensitivity of ATC-15 cells to BLM was reflected in their better growth efficiency. These cells exhibited a satisfactory growth at BLM doses that produced a permanent arrest of growth in CHO cells. The data suggest that mosquito cells might have linker DNAs shorter than those of mammalian cells, which would result in the observed both greater chromatin condensation and greater resistance to DNA damage induced by BLM as compared to CHO cells.

  20. A multipurpose vector system for the screening of libraries in bacteria, insect and mammalian cells and expression in vivo

    OpenAIRE

    Laitinen, Olli H.; Airenne, Kari J; Hytönen, Vesa P; Peltomaa, Erik; Mähönen, Anssi J.; Wirth, Thomas; Lind, Miia M.; Mäkelä, Kari A.; Toivanen, Pyry I.; Schenkwein, Diana; Heikura, Tommi; Nordlund, Henri R.; Kulomaa, Markku S.; Ylä-Herttuala, Seppo

    2005-01-01

    We have constructed a novel tetra-promoter vector (pBVboostFG) system that enables screening of gene/cDNA libraries for functional genomic studies. The vector enables an all-in-one strategy for gene expression in mammalian, bacterial and insect cells and is also suitable for direct use in vivo. Virus preparation is based on an improved mini Tn7 transpositional system allowing easy and fast production of recombinant baculoviruses with high diversity and negligible background. Cloning of the de...

  1. 昆虫细胞分类技术的应用与发展%The application and development of insect cell classification techniques

    Institute of Scientific and Technical Information of China (English)

    孙立影; 张占东

    2016-01-01

    Baculovirus-insect cell expression system as one of the four major expression systems has been widely used in biopharmaceutical industry.As the basis support of this expression system,insect cells begin to become another new cell matrix after mammalian cells,and are developed and applied in the field of vaccines and biotechnology products.However,there are significant differences between insect cells and mammalian cells in terms of cell characteristics,so establishment of a quality control method suiting characteristics of insect cells has become a problem which must be solved in biopharmaceutics.This article mainly reviews the research progress of insect cell identification methods,and provides reference for the development and establishment of individual identification methods of insect cells.%昆虫细胞杆状病毒表达系统作为四大表达系统之一,已经被广泛应用于生物制药领域,作为该表达系统的支撑基础,昆虫细胞开始成为继哺乳动物细胞之后的另一种新型细胞基质,在疫苗及生物技术产品领域得到开发应用.然而,昆虫细胞与哺乳动物细胞在细胞特性等方面存在显著差异,建立适合昆虫细胞特性的质量控制方法已经成为生物制药领域必须要解决的问题.此文仅就昆虫细胞鉴定方法研究进展做一综述,为开发及建立昆虫细胞个性化鉴别方法提供参考.

  2. Characterization of N-Glycan Structures on the Surface of Mature Dengue 2 Virus Derived from Insect Cells.

    Directory of Open Access Journals (Sweden)

    Y Lei

    Full Text Available DENV envelope glycoprotein (E is responsible for interacting with host cell receptors and is the main target for the development of a dengue vaccine based on an induction of neutralizing antibodies. It is well known that DENV E glycoprotein has two potential N-linked glycosylation sites at Asn67 and Asn153. The N-glycans of E glycoprotein have been shown to influence the proper folding of the protein, its cellular localization, its interactions with receptors and its immunogenicity. However, the precise structures of the N-glycans that are attached to E glycoprotein remain elusive, although the crystal structure of DENV E has been determined. This study characterized the structures of envelope protein N-linked glycans on mature DENV-2 particles derived from insect cells via an integrated method that used both lectin microarray and MALDI-TOF-MS. By combining these methods, a high heterogeneity of DENV N-glycans was found. Five types of N-glycan were identified on DENV-2, including mannose, GalNAc, GlcNAc, fucose and sialic acid; high mannose-type N-linked oligosaccharides and the galactosylation of N-glycans were the major structures that were found. Furthermore, a complex between a glycan on DENV and the carbohydrate recognition domain (CRD of DC-SIGN was mimicked with computational docking experiments. For the first time, this study provides a comprehensive understanding of the N-linked glycan profile of whole DENV-2 particles derived from insect cells.

  3. Insect Keepers

    Science.gov (United States)

    Moore, Virginia J.; Chessin, Debby A.; Theobald, Becky

    2010-01-01

    Insects are fascinating creatures--especially when you and your students get up close and personal with them! To that end, the authors facilitated an inquiry-based investigation with an emphasis on identification of the different types of insects found in the school yard, their characteristics, their habitat, and what they eat, while engaging the…

  4. Production of Hev b5 as a fluorescent biotin-binding tripartite fusion protein in insect cells

    International Nuclear Information System (INIS)

    The presented green fluorescent protein and streptavidin core-based tripartite fusion system provides a simple and efficient way for the production of proteins fused to it in insect cells. This fusion protein forms a unique tag, which serves as a multipurpose device enabling easy optimization of production, one-step purification via streptavidin-biotin interaction, and visualization of the fusion protein during downstream processing and in applications. In the present study, we demonstrate the successful production, purification, and detection of a natural rubber latex allergen Hev b5 with this system. We also describe the production of another NRL allergen with the system, Hev b1, which formed large aggregates and gave small yields in purification. The aggregates were detected at early steps by microscopical inspection of the infected insect cells producing this protein. Therefore, this fusion system can also be utilized as a fast indicator of the solubility of the expressed fusion proteins and may therefore be extremely useful in high-throughput expression approaches

  5. Respiratory syncytial virus fusion glycoprotein expressed in insect cells form protein nanoparticles that induce protective immunity in cotton rats.

    Directory of Open Access Journals (Sweden)

    Gale Smith

    Full Text Available Respiratory Syncytial Virus (RSV is an important viral agent causing severe respiratory tract disease in infants and children as well as in the elderly and immunocompromised individuals. The lack of a safe and effective RSV vaccine represents a major unmet medical need. RSV fusion (F surface glycoprotein was modified and cloned into a baculovirus vector for efficient expression in Sf9 insect cells. Recombinant RSV F was glycosylated and cleaved into covalently linked F2 and F1 polypeptides that formed homotrimers. RSV F extracted and purified from insect cell membranes assembled into 40 nm protein nanoparticles composed of multiple RSV F oligomers arranged in the form of rosettes. The immunogenicity and protective efficacy of purified RSV F nanoparticles was compared to live and formalin inactivated RSV in cotton rats. Immunized animals induced neutralizing serum antibodies, inhibited virus replication in the lungs, and had no signs of disease enhancement in the respiratory track of challenged animals. RSV F nanoparticles also induced IgG competitive for binding of palivizumab neutralizing monoclonal antibody to RSV F antigenic site II. Antibodies to this epitope are known to protect against RSV when passively administered in high risk infants. Together these data provide a rational for continued development a recombinant RSV F nanoparticle vaccine candidate.

  6. Multiorganismal Insects: Diversity and Function of Resident Microorganisms

    OpenAIRE

    Douglas, Angela E.

    2014-01-01

    All insects are colonized by microorganisms on the insect exoskeleton, in the gut and hemocoel, and within insect cells. The insect microbiota is generally different from microorganisms in the external environment, including ingested food. Specifically, certain microbial taxa are favored by the conditions and resources in the insect habitat, by their tolerance of insect immunity, and by specific mechanisms for their transmission. The resident microorganisms can promote insect fitness by contr...

  7. Saponins do not affect the ecdysteroid receptor complex but cause membrane permeation in insect culture cell lines.

    Science.gov (United States)

    De Geyter, Ellen; Swevers, Luc; Soin, Thomas; Geelen, Danny; Smagghe, Guy

    2012-01-01

    This project studied the effects of four saponins with a triterpenoid (Quillajasaponaria saponin and aescin) or steroid structure (digitonin and diosgenin which is the deglycosylated form of dioscin) on insect cells, namely Schneider S2 cells of Drosophila melanogaster (Diptera). A series of different experiments were performed to investigate potential mechanisms of action by saponins with regard to ecdysteroid receptor (EcR) responsiveness, cell viability, cell membrane permeation, and induction of apoptosis with DNA fragmentation and caspase-3 like activity. Major results were that (1) exposure of S2 cells containing an EcR-based reporter construct to a concentration series of each saponin scored no EcR activation, while (2) a loss of ecdysteroid signaling was observed with median inhibitory concentrations (IC(50)'s) of 3-50 μM, and in parallel (3) a concentration-dependent change in loss of cell numbers in an cell viability assay with median effective concentrations (EC(50)'s) of 8-699 μM. In continuation, it was of interest that (4) a trypan blue assay with Q. saponaria saponin confirmed the cell membrane permeation effect leading to cell toxicity with a median lethal concentration (LC(50)) value of 44 μM, and interestingly this effect was very rapid. Another three interesting observations were that (5) exposure to 20E at 500 nM as used in the EcR-based report assay induced caspase-3 like activities which may help to explain the discrepancies between loss of EcR-responsiveness and cell viability, (6) low concentrations of saponins induced DNA fragmentation and caspase-3 like activities, confirming their potential to induce apoptosis, and (7) the saponin effects were counteracted with addition of cholesterol to the culture medium. In general the data obtained provide evidence that the anti-ecdysteroid action by saponins is not based on a true antagonistic interaction with EcR signaling, but can be explained by a cytotoxic action due to permeation of the

  8. Oenocytes in insects

    Directory of Open Access Journals (Sweden)

    GF Martins

    2012-08-01

    Full Text Available Oenocytes are insect cells responsible for lipid processing and detoxification. Of ectodermic origin, they are found in close association with the insect epidermis, or fat body cells, or both depending on the insect species and developmental stage. They are easily distinguishable either by staining or by their ability to form cell clusters lined by a basal lamina, which makes it possible to isolate them from other cells. The most noticeable characteristic of the oenocytes ultrastructure is the presence of a well-developed smooth endoplasmic reticulum that can fill almost entire cell cytoplasm that for a long time was suggestive of lipid processing capacity. This capacity was confirmed lately through the usage of genetic, molecular and biochemistry approaches and other functions are also addressed to these cells, such as cuticular hydrocarbons and pheromones synthesis and detoxification. Additionally, oenocytes are considered analogous to mammalian hepatocytes based on their gene expression profiles and cell functions. In spite of the current knowledge about oenocytes, much about their protein expression profile remains unknown. In this review we provide a general overview of the state of the art related to oenocytes studies and certain morphological and biochemical aspects of such cells crucial for insect survival.

  9. Dissolved carbon dioxide determines the productivity of a recombinant hemagglutinin component of an influenza vaccine produced by insect cells.

    Science.gov (United States)

    Meghrous, Jamal; Khramtsov, Nikolai; Buckland, Barry C; Cox, Manon M J; Palomares, Laura A; Srivastava, Indresh K

    2015-11-01

    Dissolved carbon dioxide (dCO2 ) accumulation during cell culture has been recognized as an important parameter that needs to be controlled for successful scale-up of animal cell culture because above a certain concentration there are adverse effects on cell growth performance and protein production. We investigated the effect of accumulation of dCO2 in bioreactor cultures of expresSF+(®) insect cells infected with recombinant baculoviruses expressing recombinant influenza virus hemagglutinins (rHA). Different strategies for bioreactor cultures were used to obtain various ranges of concentrations of dCO2 (200 mmHg) and to determine their effects on recombinant protein production and cell metabolic activity. We show that the accumulation of dCO2 at levels > 100 mmHg resulted in reduced metabolic activity, slowed cell growth, prolonged culture viability after infection, and decreased infection kinetics. The reduced rHA yields were not caused by the decrease in the extracellular pH that resulted from dCO2 accumulation, but were most likely due to the effect of dCO2 accumulation in cells. The results obtained here at the 2 L scale have been used for the design of large-scale processes to manufacture the rHA based recombinant vaccine Flublok™ at the 2500 L scale Biotechnol. Bioeng. 2015;112: 2267-2275. © 2015 Wiley Periodicals, Inc.

  10. Characterization of oligosaccharide structures on a chimeric respiratory syncytial virus protein expressed in insect cell line Sf9

    Energy Technology Data Exchange (ETDEWEB)

    Wathen, M.W.; Aeed, P.A.; Elhammer, A.P. (Upjohn Co., Kalamazoo, MI (United States))

    1991-03-19

    The oligosaccharide structures added to a chimeric protein (FG) composed of the extracellular domains of respiratory syncytial virus F and G proteins, expressed in the insect cell line Sf9, were investigated. Cells were labeled in vivo with ({sup 3}H)glucosamine and infected wit a recombinant baculovirus containing the FG gene. The secreted chimeric protein was isolated by immunoprecipitation and subjected to oligosaccharide analysis. The FG protein contains two types of O-linked oligosaccharides: GalNAc and Gal{beta}1-3GalNAc constituting 17 and 66% of the total number of structures respectively. Only one type of N-linked oligosaccharide, constituting the remaining 17% of the structures on FG, was detected: a trimannosyl core structure with a fucose residue linked {alpha}1-6 to the asparagine-linked N-acetylglucosamine.

  11. Insect Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Records of past temperature and environment derived from beetle and other insect fossils. Parameter keywords describe what was measured in this data set. Additional...

  12. The key molecular events during Macrobrachium rosenbergii nodavirus (MrNV) infection and replication in Sf9 insect cells.

    Science.gov (United States)

    Somrit, Monsicha; Watthammawut, Atthaboon; Chotwiwatthanakun, Charoonroj; Weerachatyanukul, Wattana

    2016-09-01

    In this study we demonstrated that Macrobrachium rosenbergii nodavirus (MrNV) was able to internalize and replicate in Sf9 insect cells, with levels of infection altered by substances affecting the caveolin-(CAV) mediated endocytosis pathway. The use of Sf9 cells for efficient MrNV replication and propagation was demonstrated by confocal microscopy and PCR amplification, through which early viral binding and internalization were initially detectable at 30min post-infection; whereas at 72h, the distinguishable sign of late-MrNV infection was observable as the gradual accumulation of a cytopathic effect (CPE) in the cells, ultimately resulting in cellular disruption. Moreover, during the early period of infection, the MrNV signals were highly co-localized with CAV1 signals of the CAV-mediated endocytosis pathway. The use of genistein as an inhibitor of the CAV-mediated endocytosis pathway significantly reduced MrNV and CAV1 co-localization, and also reduced the levels of MrNV infection in Sf9 cells as shown by PCR and ELISA. Moreover, the addition of the pathway agonist okadaic acid not only recovered but also augmented both the levels of MrNV co-localization with CAV1 and of Sf9 infection in the presence of genistein inhibition; therefore demonstrating that MrNV infection in Sf9 cells was associated with the CAV-mediated endocytosis pathway machinery.

  13. Eicosanoids mediate insect hemocyte migration

    Science.gov (United States)

    Hemocyte chemotaxis toward infection and wound sites is an essential component of insect defense reactions, although the biochemical signal mechanisms responsible for mediating chemotaxis in insect cells are not well understood. Here we report on the outcomes of experiments designed to test the hyp...

  14. Binding affinity to and dependence on some opioidsin Sf9 insect cells expressing human μ-opioid receptor

    Institute of Scientific and Technical Information of China (English)

    LIUZhong-Hua; HEYou; JINWen-Qiao; CHENXin-Jian; ZHANGHong-Ping; SHENQing-Xiang; CHIZhi-Qiang

    2003-01-01

    AIM: To investigate the receptor binding affinity and naloxone-precipitated cAMP overshoot of dihydroetorphine,fentanyl, heroin, and pethidine in Sf9 insect cells expressing human μ-opioid receptor (Sf9-μ cells). METHODS:Competitive binding assay of [3H]ohmefentanyl was used to reveal the affinity for μ-opioid receptor in Sf9-μ cells.[3H]cAMP RIA was used to determine cAMP level. Antinociceptive activity was evaluated using 55℃ mouse hotplate test. Naloxone-precipitated withdrawal jumping was used to reflect physical dependence in mice. RESULTS:All drugs displayed antinociceptive activity and produced physical dependence in mice. The Ki values ofdihydroetorphine, fentanyl, heroin, and pethidine in competitive binding assay were (0.85±0.20)nmol, (59.1±11.7)nmol, (0.36±0.13)μmol, and (12.2±3.8) μmol respectively. The binding affinities of these drugs for μ-opioidreceptor in Sf9-μ cells were paralleled to their antinociceptive activities in mice. After chronic pretreatment withthese drugs, naloxone induced cAMP withdrawal overshoot in Sf9-μ cells. The dependence index in Sf9-μ cellswas calculated as Ki value in competitive binding assay over ECs0 value in naloxone-precipitated cAMP assay, Thephysical dependence index in mice was calculated as antinociceptive ED50/withdrawal jumping cumulative EDs0.There was a good linear correlation between dependence index in Sf9-μ cells and physical dependence index inmice. CONCLUSION: The Sf9-μ cells could be used as a cell model to evaluate the receptor binding affinity andphysical dependent liability of analgesic agents.

  15. Quinuclidine compounds differently act as agonists of Kenyon cell nicotinic acetylcholine receptors and induced distinct effect on insect ganglionic depolarizations.

    Science.gov (United States)

    Mathé-Allainmat, Monique; Swale, Daniel; Leray, Xavier; Benzidane, Yassine; Lebreton, Jacques; Bloomquist, Jeffrey R; Thany, Steeve H

    2013-12-01

    We have recently demonstrated that a new quinuclidine benzamide compound named LMA10203 acted as an agonist of insect nicotinic acetylcholine receptors. Its specific pharmacological profile on cockroach dorsal unpaired median neurons (DUM) helped to identify alpha-bungarotoxin-insensitive nAChR2 receptors. In the present study, we tested its effect on cockroach Kenyon cells. We found that it induced an inward current demonstrating that it bounds to nicotinic acetylcholine receptors expressed on Kenyon cells. Interestingly, LMA10203-induced currents were completely blocked by the nicotinic antagonist α-bungarotoxin. We suggested that LMA10203 effect occurred through the activation of α-bungarotoxin-sensitive receptors and did not involve α-bungarotoxin-insensitive nAChR2, previously identified in DUM neurons. In addition, we have synthesized two new compounds, LMA10210 and LMA10211, and compared their effects on Kenyon cells. These compounds were members of the 3-quinuclidinyl benzamide or benzoate families. Interestingly, 1 mM LMA10210 was not able to induce an inward current on Kenyon cells compared to LMA10211. Similarly, we did not find any significant effect of LMA10210 on cockroach ganglionic depolarization, whereas these three compounds were able to induce an effect on the central nervous system of the third instar M. domestica larvae. Our data suggested that these three compounds could bind to distinct cockroach nicotinic acetylcholine receptors. PMID:23884575

  16. Partial synchronization dynamics of coupled ultradian oscillators comprising an insect neurosecretory cell system.

    Science.gov (United States)

    Ichikawa, Toshio

    2009-12-01

    An insulin-related peptide, bombyxin, in the silkmoth Bombyx mori is secreted by four pairs of cerebral neurosecretory cells that form a weakly coupled oscillator system to produce a pulsatile pattern of hormone secretion. The activity of individual bombyxin-producing (BP) cells oscillated with different periods (20-70 min). The population of BP cells exhibited complex phase dynamics, including spontaneous synchronization and desynchronization of different combinations of cells. Statistical cross-correlation analyses of oscillation patterns between BP cells revealed that one cell usually correlated closely with a few particular cells of similar periodicity. Close investigation of the phase differences between individual active phases of the related cell pairs revealed that an inphase synchronous state was usually maintained for many cycles, whereas an antiphase state was transient, lasting for a few cycles. In contrast, antiphase synchronous states often occurred between several cell pairs when the brain containing the cerebral neurosecretory cell system was disconnected from the ventral nerve cord containing the neuronal mechanism that induced periodic heartbeat reversals at intervals of 80-110 min and exerted a periodic suppressive or phase-resetting effect on individual BP cells. These results suggest that the internal coupling mechanism in the BP cell system is not sufficient to maintain an in-phase synchronous state in the heterogeneous cell population, and that the external phase resetting mechanism may assist in-phase synchronization of many neurosecretory cells to generate an overall pulsatile pattern of bombyxin secretion.

  17. Toxicity and mode of action of insecticidal Cry1A proteins from Bacillus thuringiensis in an insect cell line, CF-1.

    Science.gov (United States)

    Portugal, Leivi; Gringorten, J Lawrence; Caputo, Guido F; Soberón, Mario; Muñoz-Garay, Carlos; Bravo, Alejandra

    2014-03-01

    Bacillus thuringiensis Cry toxins are insecticidal proteins used to control insect pests. The interaction of Cry toxins with the midgut of susceptible insects is a dynamic process involving activation of the toxin, binding to midgut receptors in the apical epithelium and conformational changes in the toxin molecule, leading to pore formation and cell lysis. An understanding of the molecular events underlying toxin mode of action is essential for the continued use of Cry toxins. In this work, we examined the mechanism of action of Cry1A toxins in the lepidopteran cell line CF-1, using native Cry1Ab and mutant forms of this protein that interfer with different steps in the mechanism of action, specifically, receptor binding, oligomerization or pore formation. These mutants lost activity against both Manduca sexta larvae and CF-1 cells. We also analyzed a mutation created in domain I of Cry1Ab, in which helix α-1 and part of helix α-2 were deleted (Cry1AbMod). Cry1AbMod is able to oligomerize in the absence of toxin receptors, and although it shows reduced activity against some susceptible insects, it kills insect pests that have developed resistance to native Cry1Ab. Cry1AbMod showed enhanced toxicity to CF-1, suggesting that oligomerization of native Cry1Ab may be a limiting step in its activity against CF-1 cells. The toxicity of Cry1Ac and Cry1AcMod were also analyzed. Our results suggest that some of the steps in the mode of action of Cry1A toxins are conserved in vivo in insect midgut cells and in vitro in an established cell line, CF-1. PMID:24189038

  18. Effects of long- and short-term passage of insect cells in different culture media on baculovirus replication.

    Science.gov (United States)

    Lynn, D E

    2000-10-01

    Two insect cell lines that had been maintained in both serum-free (SFM) and serum-containing (SCM) media for over 5 years were each tested for their ability to replicate baculovirus. The gypsy moth cell line, IPLB-LdEIta (Ld), produced similar (not statistically different) amounts of gypsy moth nucleopolyhedrovirus (LdMNPV) occlusion bodies (OBs) in the two media (serum-free Ex-Cell 400 and TC-100 with 9% (v/v) fetal bovine serum, SCM(1)) but produced more of the Autographa californica nucleopolyhedrovirus (AcMNPV) OBs in SFM than in SCM(1). When Ld cells normally grown in SCM(1) were switched to SFM, production of OBs from both viruses improved and, after three passages, reached higher levels of AcMNPV production than in cells normally maintained in that medium. Alternatively, cells switched from SFM to SCM(1) initially produced as much (in the case of LdMNPV) or higher (in the case of AcMNPV) levels of virus OBs than cells normally maintained in SCM(1) but productivity dropped off over subsequent passages such that after five passages in SCM(1), cells produced substantially fewer OBs of both viruses. A fall armyworm cell line (IPLB-SF21AE; Sf) showed slightly different effects from long- and short-term passage in SFM (Ex-Cell 400) or SCM(2) (TMN-FH). Cells maintained in SFM produced about 20 times more AcMNPV OBs than cells maintained long-term in SCM. Sf cells switched from SFM to SCM maintained the level of production of that seen in SFM at the first passage, but quickly dropped off OB production levels to that normally seen in SCM. Alternatively, SCM-maintained Sf cells produced higher levels at the first passage in SFM and, within five passages in SFM, reached levels found in cells maintained for long term in this medium. Under the conditions in which these two cell lines were infected, the highest levels of AcMNPV OB production in Ld cells were about five times that of Sf cells. In a separate series of experiments, cells normally grown in SFM were passaged

  19. Inhibition of protein kinase C decreases sensitivity of GABA receptor subtype to fipronil insecticide in insect neurosecretory cells.

    Science.gov (United States)

    Murillo, Laurence; Hamon, Alain; Es-Salah-Lamoureux, Zeineb; Itier, Valérie; Quinchard, Sophie; Lapied, Bruno

    2011-12-01

    Phosphorylation by serine/threonine kinases has been described as a new mechanism for regulating the effects of insecticides on insect neuronal receptors and channels. Although insect GABA receptors are commercially important targets for insecticides (e.g. fipronil), their modulation by kinases is poorly understood and the influence of phosphorylation on insecticide sensitivity is unknown. Using the whole-cell patch-clamp technique, we investigated the modulatory effect of PKC and CaMKinase II on GABA receptor subtypes (GABAR1 and GABAR2) in DUM neurons isolated from the terminal abdominal ganglion (TAG) of Periplaneta americana. Chloride currents through GABAR2 were selectively abolished by PMA and PDBu (the PKC activators) and potentiated by Gö6983, an inhibitor of PKC. Furthermore, using KN-62, a specific CaMKinase II inhibitor, we demonstrated that CaMKinase II activation was also involved in the regulation of GABAR2 function. In addition, using CdCl(2) (the calcium channel blocker) and LOE-908, a blocker of TRPγ, we revealed that calcium influx through TRPγ played an important role in kinase activations. Comparative studies performed with CACA, a selective agonist of GABAR1 in DUM neurons confirmed the involvement of these kinases in the specific regulation of GABAR2. Furthermore, our study reported that GABAR1 was less sensitive than GABAR2 to fipronil. This was demonstrated by the biphasic concentration-response curve and the current-voltage relationship established with both GABA and CACA. Finally, we demonstrated that GABAR2 was 10-fold less sensitive to fipronil following inhibition of PKC, whereas inhibition of CaMKinase II did not alter the effect of fipronil. PMID:21684305

  20. Identification of a transformer homolog in the acorn worm, Saccoglossus kowalevskii, and analysis of its activity in insect cells.

    Science.gov (United States)

    Suzuki, Masataka G; Tochigi, Mayuko; Sakaguchi, Honami; Aoki, Fugaku; Miyamoto, Norio

    2015-06-01

    The transformer (tra) gene is an intermediate component of the sex determination hierarchy in many insect species. The homolog of tra is also found in two branchiopod crustacean species but is not known outside arthropods. We have isolated a tra homolog in the acorn worm, Saccoglossus kowalevskii, which is a hemichordate belonging to the deuterostome superphylum. The full-length complementary DNA (cDNA) of the S. kowalevskii tra homolog (Sktra) has a 3786-bp open reading frame that encodes a 1261-amino acid sequence including a TRA-CAM domain and an arginine/serine (RS)-rich domain, both of which are characteristic of TRA orthologs. Reverse transcription PCR (RT-PCR) analyses demonstrated that Sktra showed no differences in expression patterns between testes and ovaries, but its expression level was approximately 7.5-fold higher in the testes than in the ovaries. TRA, together with the protein product of the transformer-2 (tra-2) gene, assembles on doublesex (dsx) pre-messenger RNA (mRNA) via the cis-regulatory element, enhancing female-specific splicing of dsx in Drosophila. To understand functional conservation of the SkTRA protein as a dsx-splicing activator, we investigated whether SkTRA is capable of inducing female-specific splicing of the Drosophila dsx. Ectopic expression of Sktra cDNA in insect cultured cells did not induce the female-specific splicing of dsx. On the other hand, forced expression of Sktra-2 (a tra-2 homolog of S. kowalevskii) was able to induce the female-specific dsx splicing. These results demonstrate that the function as a dsx-splicing activator is not conserved in SkTRA even though SkTRA-2 is capable of functionally replacing the Drosophila TRA-2. We have also found a tra homolog in an echinoderm genome. This study provides the first evidence that that tra is conserved not only in arthropods but also in basal species of deuterostoms.

  1. Nonviral Production of Human Interleukin-7 in Spodoptera Frugiperda Insect Cells as a Soluble Recombinant Protein

    OpenAIRE

    Maryam Mirzaei; Yan Xu; Elias, Cynthia B.; Satya Prakash

    2008-01-01

    Human interleukin-7 (hIL-7) is a cytokine secreted by the stromal cells of the red marrow. It is important for proliferation during certain stages of B-cell maturation and for T and NK cell survival, development, and homeostasis. It is a critical growth factor for enhancement and recovery of the immune T-cell. Because of its strong immunomodulatory effects, hIL-7 may become a valuable supplementary agent for immunotherapeutical treatments in patients with HIV infection or immunodeficiency. Hu...

  2. GFP-based evaluation system of recombinant expression through the secretory pathway in insect cells and its application to the extracellular domains of class C GPCRs

    OpenAIRE

    Ashikawa, Yuji; Ihara, Makoto; Matsuura, Noriko; Fukunaga, Yuko; Kusakabe, Yuko; Yamashita, Atsuko

    2011-01-01

    Applications of the GFP-fusion technique have greatly facilitated evaluations of the amounts and qualities of sample proteins used for structural analyses. In this study, we applied the GFP-based sample evaluation to secreted protein expression by insect cells. We verified that a GFP variant, GFPuv, retains proper folding and monodispersity within all expression spaces in Sf9 cells, such as the cytosol, organelles, and even the extracellular space after secretion, and thus can serve as a prop...

  3. Effects of food nutrient content, insect age and stage in the feeding cycle on the FMRFamide immunoreactivity of diffuse endocrine cells in the locust gut

    OpenAIRE

    Zudaire, E. (Enrique); Simpson, S J; Montuenga, L M

    1998-01-01

    We have studied the influence of variations in dietary protein and digestible carbohydrate content, of insect age and of time during the feeding cycle on the endocrine cells of the ampullar region of the midgut in the African migratory locust Locusta migratoria L. Morphometric analysis of FMRFamide-like immunoreactivity was used as an indirect measure of the amount of FMRFamide-related peptides (FaRPs) stored in the gut endocrine cells. There was a highly significant correlation between FaRP ...

  4. Establishment and characterization of insect cell lines from 10 lepidopteran species.

    Science.gov (United States)

    Goodman, C L; El Sayed, G N; McIntosh, A H; Grasela, J J; Stiles, B

    2001-06-01

    Cell lines from selected lepidopteran species were established for the overall purpose of use in baculovirus production. A total of 36 new cell lines from 10 lepidopteran species were generated, including cell lines from a pyralid, the European corn borer, Ostrinia nubilalis, a plutellid, the diamondback moth, Plutella xylostella, as well as eight noctuids: the black cutworm, Agrotis ipsilon, the celery looper, Anagrapha falcifera, the velvetbean caterpillar, Anticarsia gemmatalis, the corn earworm, Helicoverpa zea, the tobacco budworm, Heliothis virescens, the beet armyworm, Spodoptera exigua, the fall armyworm, Spodoptera frugiperda, and the cabbage looper, Trichoplusia ni. Tissues used for cell line establishment included fat bodies, ovaries, testes, or whole embryos/larvae/pupae. All the cell lines were subcultured numerous times, characterized by isoenzyme analysis and/or deoxyribonucleic acid amplification fingerprinting using polymerase chain reaction, and stored in liquid nitrogen. Many of the cell lines were adapted to grow in serum-free medium, with cell lines from A. ipsilon and H. virescens being adapted to suspension culture using shaker flasks. The potential use for these cell lines in baculovirus production is discussed. PMID:11515970

  5. [Expression of rice dwarf virus outer coat protein gene(S8) in insect cells].

    Science.gov (United States)

    Li, S; Liu, H; Chen, Z; Li, Y

    2001-04-01

    Outer coat protein gene(S8) of RDV was cloned into the transfer vector pVL 1393 to construct a recombinant vector pVL1393-S8. The recombinant vector pVL1393-S8 and the linear baculovirus RP23. LacZ were cotransfected into sf9 cells to produce the recombinant virus RP23-S8. RP23-S8 infected sf9 cells were collected and analysed by SDS-PAGE and Western-blot. The results showed that the S8 gene of RDV was expressed in sf9 cells and the expression level of sf9 cells was higher between 72-96 h after infected.

  6. Environmental RNAi in herbivorous insects.

    Science.gov (United States)

    Ivashuta, Sergey; Zhang, Yuanji; Wiggins, B Elizabeth; Ramaseshadri, Partha; Segers, Gerrit C; Johnson, Steven; Meyer, Steve E; Kerstetter, Randy A; McNulty, Brian C; Bolognesi, Renata; Heck, Gregory R

    2015-05-01

    Environmental RNAi (eRNAi) is a sequence-specific regulation of endogenous gene expression in a receptive organism by exogenous double-stranded RNA (dsRNA). Although demonstrated under artificial dietary conditions and via transgenic plant presentations in several herbivorous insects, the magnitude and consequence of exogenous dsRNA uptake and the role of eRNAi remains unknown under natural insect living conditions. Our analysis of coleopteran insects sensitive to eRNAi fed on wild-type plants revealed uptake of plant endogenous long dsRNAs, but not small RNAs. Subsequently, the dsRNAs were processed into 21 nt siRNAs by insects and accumulated in high quantities in insect cells. No accumulation of host plant-derived siRNAs was observed in lepidopteran larvae that are recalcitrant to eRNAi. Stability of ingested dsRNA in coleopteran larval gut followed by uptake and transport from the gut to distal tissues appeared to be enabling factors for eRNAi. Although a relatively large number of distinct coleopteran insect-processed plant-derived siRNAs had sequence complementarity to insect transcripts, the vast majority of the siRNAs were present in relatively low abundance, and RNA-seq analysis did not detect a significant effect of plant-derived siRNAs on insect transcriptome. In summary, we observed a broad genome-wide uptake of plant endogenous dsRNA and subsequent processing of ingested dsRNA into 21 nt siRNAs in eRNAi-sensitive insects under natural feeding conditions. In addition to dsRNA stability in gut lumen and uptake, dosage of siRNAs targeting a given insect transcript is likely an important factor in order to achieve measurable eRNAi-based regulation in eRNAi-competent insects that lack an apparent silencing amplification mechanism.

  7. Insect Pupil Mechanisms. II. Pigment Migration in Retinula Cells of Butterflies

    NARCIS (Netherlands)

    Stavenga, D.G.; Numan, J.A.J.; Tinbergen, J.; Kuiper, J.W.

    1977-01-01

    The hypothesis that the glow observable in dark adapted butterfly eyes is extinguished upon light adaptation by the action of migrating retinula cell pigment granules has been investigated. Experimental procedures applying optical methods to intact, living animals were similar to those used previous

  8. Affordable uniform isotope labeling with {sup 2}H, {sup 13}C and {sup 15}N in insect cells

    Energy Technology Data Exchange (ETDEWEB)

    Sitarska, Agnieszka; Skora, Lukasz; Klopp, Julia; Roest, Susan; Fernández, César; Shrestha, Binesh; Gossert, Alvar D., E-mail: alvar.gossert@novartis.com [Novartis Institutes for BioMedical Research (Switzerland)

    2015-06-15

    For a wide range of proteins of high interest, the major obstacle for NMR studies is the lack of an affordable eukaryotic expression system for isotope labeling. Here, a simple and affordable protocol is presented to produce uniform labeled proteins in the most prevalent eukaryotic expression system for structural biology, namely Spodoptera frugiperda insect cells. Incorporation levels of 80 % can be achieved for {sup 15}N and {sup 13}C with yields comparable to expression in full media. For {sup 2}H,{sup 15}N and {sup 2}H,{sup 13}C,{sup 15}N labeling, incorporation is only slightly lower with 75 and 73 %, respectively, and yields are typically twofold reduced. The media were optimized for isotope incorporation, reproducibility, simplicity and cost. High isotope incorporation levels for all labeling patterns are achieved by using labeled algal amino acid extracts and exploiting well-known biochemical pathways. The final formulation consists of just five commercially available components, at costs 12-fold lower than labeling media from vendors. The approach was applied to several cytosolic and secreted target proteins.

  9. Identification of a transformer homolog in the acorn worm, Saccoglossus kowalevskii, and analysis of its activity in insect cells.

    Science.gov (United States)

    Suzuki, Masataka G; Tochigi, Mayuko; Sakaguchi, Honami; Aoki, Fugaku; Miyamoto, Norio

    2015-06-01

    The transformer (tra) gene is an intermediate component of the sex determination hierarchy in many insect species. The homolog of tra is also found in two branchiopod crustacean species but is not known outside arthropods. We have isolated a tra homolog in the acorn worm, Saccoglossus kowalevskii, which is a hemichordate belonging to the deuterostome superphylum. The full-length complementary DNA (cDNA) of the S. kowalevskii tra homolog (Sktra) has a 3786-bp open reading frame that encodes a 1261-amino acid sequence including a TRA-CAM domain and an arginine/serine (RS)-rich domain, both of which are characteristic of TRA orthologs. Reverse transcription PCR (RT-PCR) analyses demonstrated that Sktra showed no differences in expression patterns between testes and ovaries, but its expression level was approximately 7.5-fold higher in the testes than in the ovaries. TRA, together with the protein product of the transformer-2 (tra-2) gene, assembles on doublesex (dsx) pre-messenger RNA (mRNA) via the cis-regulatory element, enhancing female-specific splicing of dsx in Drosophila. To understand functional conservation of the SkTRA protein as a dsx-splicing activator, we investigated whether SkTRA is capable of inducing female-specific splicing of the Drosophila dsx. Ectopic expression of Sktra cDNA in insect cultured cells did not induce the female-specific splicing of dsx. On the other hand, forced expression of Sktra-2 (a tra-2 homolog of S. kowalevskii) was able to induce the female-specific dsx splicing. These results demonstrate that the function as a dsx-splicing activator is not conserved in SkTRA even though SkTRA-2 is capable of functionally replacing the Drosophila TRA-2. We have also found a tra homolog in an echinoderm genome. This study provides the first evidence that that tra is conserved not only in arthropods but also in basal species of deuterostoms. PMID:25868907

  10. Induction, selection and antibacterial activity of the antibacterial peptides from lepldopteran insect cultured cell lines

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    We induced 3 cell lines that were in vitro cultured from Lepidoptera with heat inactivated Escherichia coil DH5α to stimulate the antibacterial peptide followed by antibacterial activity assay,induction dynamic research and Tricine sodium dodecyl sulfate-polyacrylamide gel electrophoresis (Tricine SDS-PAGE) experiment.The antibacterial activity of the induced BTI-Tn-5B1 cell line was the highest,and the antibacterial activity increased gradually to the highest level in 16 hours after stimulation.A new antibacterial peptide with a molecular weight of about 8000 Da was preferentially induced in Trichoplusia ni BTI-Tn-5B1 ceils in 16 hours after stimulation.Antibacterial activity assays indicated that it had inhibition against Staphylococcus aureus,Escherichia coli K12D31 and Salmonella derby.It has especially strong inhibition against Gram-negative bacteria such as Escherichia coli KI2D31 and Salmonella derby.

  11. Expression of hemagglutinin protein from the avian influenza virus H5N1 in a baculovirus/insect cell system significantly enhanced by suspension culture

    Directory of Open Access Journals (Sweden)

    Spencer Lynn

    2006-02-01

    Full Text Available Abstract Background Prevention of a possible avian influenza pandemic necessitates the development of rapid diagnostic tests and the eventual production of a vaccine. Results For vaccine production, hemagglutinin (HA1 from avian influenza H5N1 was expressed from a recombinant baculovirus. Recombinant HA1 was expressed in monolayer or suspension culture insect cells by infection with the recombinant baculovirus. The yield of rHA1 from the suspension culture was 68 mg/l, compared to 6 mg/l from the monolayer culture. Immunization of guinea pigs with 50 μg of rHA1 yielded hemagglutinin inhibition and virus neutralization titers of 1:160 after two times vaccination with rHA1 protein. Conclusion Thus, the production of rHA1 using an insect suspension cell system provides a promising basis for economical production of a H5 antigen.

  12. Fluorescence in insects

    Science.gov (United States)

    Welch, Victoria L.; Van Hooijdonk, Eloise; Intrater, Nurit; Vigneron, Jean-Pol

    2012-10-01

    Fluorescent molecules are much in demand for biosensors, solar cells, LEDs and VCSEL diodes, therefore, considerable efforts have been expended in designing and tailoring fluorescence to specific technical applications. However, naturally occurring fluorescence of diverse types has been reported from a wide array of living organisms: most famously, the jellyfish Aequorea victoria, but also in over 100 species of coral and in the cuticle of scorpions, where it is the rule, rather than the exception. Despite the plethora of known insect species, comparatively few quantitative studies have been made of insect fluorescence. Because of the potential applications of natural fluorescence, studies in this field have relevance to both physics and biology. Therefore, in this paper, we review the literature on insect fluorescence, before documenting its occurrence in the longhorn beetles Sternotomis virescens, Sternotomis variabilis var. semi rufescens, Anoplophora elegans and Stellognatha maculata, the tiger beetles Cicindela maritima and Cicindela germanica and the weevil Pachyrrhynchus gemmatus purpureus. Optical features of insect fluorescence, including emitted wavelength, molecular ageing and naturally occurring combinations of fluorescence with bioluminescence and colour-producing structures are discussed.

  13. Expression of two types of acetylcholinesterase gene from the silkworm, Bombyx mori, in insect cells

    Institute of Scientific and Technical Information of China (English)

    JIN-YAN SHANG; YA-MING SHAO; GUO-JUN LANG; GAN YUAN; ZHEN-HUA TANG; CHUAN-XI ZHANG

    2007-01-01

    Complementary DNAs encoding two types of acetylcholinesterase(AChE)were isolated from the silkworm, Bombyx mori. The type 1 (Bmace1) and type 2 (Bmace2) ORFs are 2052 and 1917 bp in length, respectively. Both the complete ORFs of the Bmaces and Cterminal truncated forms were recombined into the Bacmid baculovirus vector under the control of the polyhedrin promoter and expressed in Trichoplusia ni (Tn-5B 1-4) cells. The resulting products exhibited AChE activity and glycosylation of the expressed proteins. An inhibition assay indicated that the ace2-type enzyme was more sensitive than the acel-type enzyme to inhibition by eserine and paraoxon.

  14. Air-dried cells from the anhydrobiotic insect, Polypedilum vanderplanki, can survive long term preservation at room temperature and retain proliferation potential after rehydration.

    Science.gov (United States)

    Watanabe, Kazuyo; Imanishi, Shigeo; Akiduki, Gaku; Cornette, Richard; Okuda, Takashi

    2016-08-01

    Pv11, a cell line derived from the anhydrobiotic insect, Polypedilum vanderplanki, was preserved in a dry form (only 6% residual moisture) at room temperature for up to 251 days and restarted proliferating after rehydration. A previous study already reported survival of Pv11 cells after desiccation, but without subsequent proliferation. Here, the protocol was improved to increase survival and achieve proliferation of Pv11 cells after dry storage. The method basically included preincubation, desiccation and rehydration processes and each step was investigated. So far, preincubation in a 600 mM trehalose solution for 48 h before dehydration was the most favourable preconditioning to achieve successful dry preservation of Pv11 cells, allowing about 16% of survival after rehydration and subsequent cell proliferation. Although the simple air-dry method established for Pv11 cells here was not applicable for successful dry-preservation of other insect cell lines, Pv11 is the first dry-preservable animal cell line and will surely contribute not only to basic but also applied sciences. PMID:27207249

  15. [The expression of porcine circovirus type 2 ORF2 gene in insect cells and its character].

    Science.gov (United States)

    Fan, Hui-Ying; Chen, Huan-Chun; Tong, Tie-Zhu; Ju, Chun-Mei; Lu, Jian-Qiang; Huang, Hong-Liang

    2005-11-01

    To produce the recombinant baculovirus transfer plasmid pFast-ORF2, the ORF2 gene of Porcine Circovirus type 2 (PCV2) was subcloned into baculovirus transfer vector (pFastBac(TM1) ) using Bac-to-Bac baculovirus expression system. E. coli DH10Bac (Gibco BRL) containing baculovirus shutter vector (bacmid) and helper vector was transformed with recombinant plasmid pFast-ORF2. Within E. coli DH10Bac, the ORF2 gene was transposed into the bacmid. The colonies of E. coli containing recombinant bacmid (Bac. ORF2) were collected by blue/white selection. The Bac. ORF2 was transfected into sf9 cells to yield AcNPV carrying the PCV2 ORF2 gene, referred to as Ac. ORF2. Expression of the ORF2 gene of PCV2 was confirmed by indirect immunofluorescent assay (IIFA), SDS-PAGE and Western-blotting. The expressed ORF2 gene product had a molecular mass of 28kD and could be recognized by the positive serum of PCV2. The results indicated the ORF2 gene was properly expressed in sf9 cell. It was noteworthy that many self-assembled virus-like particles (VLPs) were found in purified and phosphotungstic acid (PTA) stained PCV2 ORF2 protein by electron microscope. The particles were of similar morphology to the PCV2 virion and some self-assembled virus-like particles had darkly stained centers that made them appear to be empty capsids. Both PCV2 particles and self-assembled particles were approximately 17 nm in diameter. PMID:16468356

  16. Insect cell entrapment, growth and recovering using a single-use fixed-bed bioreactor. Scaling up and recombinant protein production.

    Science.gov (United States)

    Ventini-Monteiro, D; Dubois, S; Astray, R M; Castillo, J; Pereira, C A

    2015-12-20

    Insect cells are largely used for industrial production of vaccines, viral vectors and recombinant proteins as well as in research and development as an important tool for biology and bioprocess studies. They grow in suspension and are semi-adherent cells. Among the cell culture systems enabling scalable bioprocess the single-use fixed-bed iCELLis(®) bioreactors offer great advantages. We have established the conditions for Drosophila melanogaster Schneider 2 (S2) and Spodoptera frugiperda (Sf9) cells entrapment into the fixed-bed, cell growth and recover from the fixed-bed once high cell densities were attained. Our established protocol allowed these cells, at a cell seeding of 2×1E5 cells/microfiber carriers (MC) (3.5×1E6cells/mL; 1.7×1E4cells/cm(2)), to grow inside a 4m(2)/200mL fixed-bed attaining a concentration of 5.3×1E6 cells/MC (9.5×1E7cells/mL; 4.7×1E5 cells/cm(2)) for S2 cells or 4.6×1E6 cells/MC (8×1E7cells/mL; 4.1×1E5cells/cm(2)) for Sf9 cells. By washing the fixed-bed, entrapped cells could then be recovered from the fixed-bed at a high rate (>85%) with high viability (>95%) by increasing the agitation to 1200/1500rpm. Although the cell yields in the fixed-bed bioreactor were comparable to those obtained in a stirred tank (respectively, 1.3×1E10 and 2.5×1E10 total cells), S2 cells stably transfected with a cDNA coding for the rabies virus glycoprotein (RVGP) showed a 30% higher preserved rRVGP production (2.5±0.1 and 1.9±0.1μg/1E7 cells), as evidenced by a conformational ELISA evaluation. These findings demonstrate not only the possibility to entrap, cultivate to high densities and recover insect cells using a single-use fixed-bed bioreactor, but also that this system provides suitable physiological conditions for the entrapped cells to produce a cell membrane associated recombinant protein with higher specific biological activity as compared to classical suspension cell cultures.

  17. Expression of the Acyl-Coenzyme A: Cholesterol Acyltransferase GFP Fusion Protein in Sf21 Insect Cells

    Science.gov (United States)

    Mahtani, H. K.; Richmond, R. C.; Chang, T. Y.; Chang, C. C. Y.; Rose, M. Franklin (Technical Monitor)

    2001-01-01

    The enzyme acyl-coenzyme A:cholesterol acyltransferase (ACAT) is an important contributor to the pathological expression of plaque leading to artherosclerosis n a major health problem. Adequate knowledge of the structure of this protein will enable pharmaceutical companies to design drugs specific to the enzyme. ACAT is a membrane protein located in the endoplasmic reticulum.t The protein has never been purified to homogeneity.T.Y. Chang's laboratory at Dartmouth College provided a 4-kb cDNA clone (K1) coding for a structural gene of the protein. We have modified the gene sequence and inserted the cDNA into the BioGreen His Baculovirus transfer vector. This was successfully expressed in Sf2l insect cells as a GFP-labeled ACAT protein. The advantage to this ACAT-GFP fusion protein (abbreviated GCAT) is that one can easily monitor its expression as a function of GFP excitation at 395 nm and emission at 509 nm. Moreover, the fusion protein GCAT can be detected on Western blots with the use of commercially available GFP antibodies. Antibodies against ACAT are not readily available. The presence of the 6xHis tag in the transfer vector facilitates purification of the recombinant protein since 6xHis fusion proteins bind with high affinity to Ni-NTA agarose. Obtaining highly pure protein in large quantities is essential for subsequent crystallization. The purified GCAT fusion protein can readily be cleaved into distinct GFP and ACAT proteins in the presence of thrombin. Thrombin digests the 6xHis tag linking the two protein sequences. Preliminary experiments have indicated that both GCAT and ACAT are expressed as functional proteins. The ultimate aim is to obtain large quantities of the ACAT protein in pure and functional form appropriate for protein crystal growth. Determining protein structure is the key to the design and development of effective drugs. X-ray analysis requires large homogeneous crystals that are difficult to obtain in the gravity environment of earth

  18. Expression and Purification of Active Recombinant Cathepsin C (Dipeptidyl Aminopeptidase I of Kuruma Prawn Marsupenaeus japonicus in Insect Cells

    Directory of Open Access Journals (Sweden)

    Gao-Feng Qiu

    2009-01-01

    Full Text Available Cathepsin C (CTSC is a lysosomal cysteine protease belonging to the papain superfamily. Our previous study showed that CTSC precursor (zymogen is localized exclusively in cortical rods (CRs of mature oocyte in the kuruma prawn Marsupenaeus japonicus, suggesting that CTSC might have roles on regulating release and/or formation of a jelly layer. In this study, enzymically active CTSC of the kuruma prawn was prepared by recombinant expression in the High Five insect cell line. The recombinant enzyme with a polyhistidine tag at its C-terminus was considered to be initially secreted into the culture medium as an inactive form of zymogen, because Western blot with anti-CTSC antibody detected a 51 kDa protein corresponding to CTSC precursor. After purification by affinity chromatography on nickel-iminodiacetic acid resin, the enzyme displayed three forms of 51, 31, and 30 kDa polypeptides. All of the forms can be recognized by antiserum raised against C-terminal polyhistidine tag, indicating that the 31 and 30 kDa forms were generated from 51 kDa polypeptide by removal of a portion of the N-terminus of propeptide. Following activation at pH 5.5 and 37∘C for 40 hours under native conditions, the recombinant CTSC (rCTSC exhibited increased activity against the synthetic substrate Gly-Phe-β-naphthylamide and optimal pH at around 5. The purified rCTSC will be useful for further characterization of its exact physiological role on CRs release and/or formation of a jelly layer in kuruma prawn.

  19. Allergies to Insect Venom

    Science.gov (United States)

    ... attracts these insects.  Use insect repellents and keep insecticide available. Treatment tips:  Venom immunotherapy (allergy shots to insect venom(s) is highly effective in preventing subsequent sting ...

  20. Prostaglandins A2 and E1 influence gene expression in an established insect cell line (BCIRL-HzAM-1 cells).

    Science.gov (United States)

    PGs and other eicosanoids exert important physiological actions in insects and other invertebrates, including influencing ion transport and mediating cellular immune defense functions. Although these actions are very well documented, we have no information on the mechanisms PGs action in insect cel...

  1. Production of Limonoids with Insect Antifeedant Activity in a Two-Stage Bioreactor Process with Cell Suspension Culture of Azadirachta indica.

    Science.gov (United States)

    Vásquez-Rivera, Andrés; Chicaiza-Finley, Diego; Hoyos, Rodrigo A; Orozco-Sánchez, Fernando

    2015-09-01

    Neem tree (Azadirachta indica) cell suspension culture is an alternative for the production of limonoids for insect control that overcomes limitations related to the supply of neem seeds. To establish conditions for cell growth and azadiracthin-related limonoid production, the effect of different sucrose concentrations, nitrate and phosphate in Murashige and Skoog (MS) medium, and the addition of one precursor and three elicitors was evaluated in shake flasks. The process was scaled up to a 3-l stirred tank bioreactor in one- and two-stage batch cultivation. In shake flasks, more than fivefold increase in the production of limonoids with the modified MS medium was observed (increase from 0.77 to 4.52 mg limonoids/g dry cell weight, DCW), while an increase of more than fourfold was achieved by adding the elicitors chitosan, salicylic acid, and jasmonic acid together (increase from 1.03 to 4.32 mg limonoids/g DCW). In the bioreactor, the volumetric production of limonoids was increased more than threefold with a two-stage culture in day 18 (13.82 mg limonoids/l in control single-stage process and 41.44 mg/l in two-stage process). The cultivation and operating mode of the bioreactor reported in this study may be adapted and used in optimization and process plant development for production of insect antifeedant limonoids with A. indica cell suspension cultures.

  2. Progress on Insect Cell Serum-free Media%昆虫细胞无血清培养基研究进展

    Institute of Scientific and Technical Information of China (English)

    马伟; 王家敏; 令世鑫; 马桂兰; 马花; 乔自林; 马忠仁; 冯玉萍

    2016-01-01

    随着昆虫杆状病毒表达载体系统的广泛应用,昆虫细胞大规模无血清培养已成为一种发展趋势。目前的昆虫细胞培养基中主要有糖类、维生素、氨基酸、脂类、无机盐、有机酸等基础成分,此外还需要添加血清或酵母提取物和水解乳蛋白等血清替代物。然而使用血清会带来诸多难以解决的问题,因此开发使用血清替代物和无血清培养基已成为生物制品行业关注的主要方向。论文综述了昆虫细胞无血清培养基的研究进展,包括研究历程、研究现状、基础成分和其他添加物等。%With the wide application of insect baculovirus expression vector system,the large scale of insect cell culture has become a developing trend.At present,there are some basic elements such as sugars,vita-mins,amino acids,lipids,inorganic salts and organic acids in the insect cell culture media,and it also needs to add serum or serum substitutes like yeastolate and lactalbumin hydrolysate.However,serum will bring many difficulties if being used,so developing and using the serum substitutes and serum-free media has become the main research direction of the biological product industry.This paper summarized the re-search progress on insect cell serum-free media,including the research history,research status,basic com-ponents and other additives,etc..

  3. Production of N-acetylgalactosaminyl-transferase 2 (GalNAc-T2) fused with secretory signal Igκ in insect cells.

    Science.gov (United States)

    Horynová, Milada; Takahashi, Kazuo; Hall, Stacy; Renfrow, Matthew B; Novak, Jan; Raška, Milan

    2012-02-01

    The human UDP-N-acetyl-α-d-galactosamine:polypeptide N-acetylgalactosaminyl-transferase 2 (GalNAc-T2) is one of the key enzymes that initiate synthesis of hinge-region O-linked glycans of human immunoglobulin A1 (IgA1). We designed secreted soluble form of human GalNAc-T2 as a fusion protein containing mouse immunoglobulin light chain kappa secretory signal and expressed it using baculovirus and mammalian expression vectors. The recombinant protein was secreted by insect cells Sf9 and human HEK 293T cells in the culture medium. The protein was purified from the media using affinity Ni-NTA chromatography followed by stabilization of purified protein in 50mM Tris-HCl buffer at pH 7.4. Although the purity of recombinant GalNAc-T2 was comparable in both expression systems, the yield was higher in Sf9 insect expression system (2.5mg of GalNAc-T2 protein per 1L culture medium). The purified soluble recombinant GalNAc-T2 had an estimated molecular mass of 65.8kDa and its amino-acid sequence was confirmed by mass-spectrometric analysis. The enzymatic activity of Sf9-produced recombinant GalNAc-T2 was determined by the quantification of enzyme-mediated attachment of GalNAc to synthetic IgA1 hinge-region peptide as the acceptor and UDP-GalNAc as the donor. In conclusion, murine immunoglobulin kappa secretory signal was used for production of secreted enzymatically active GalNAc-T2 in insect baculovirus expression system.

  4. Glycosylation of recombinant human thyroid peroxidase ectodomain of insect cell origin has little effect on recognition by serum thyroid peroxidase antibody

    Institute of Scientific and Technical Information of China (English)

    LIU Ming-ming; LI Qing; ZHAO Lan-lan; GAO Ying; HUANG You-yuan; LU Gui-zhi; GAO Yan-ming

    2013-01-01

    Background Thyroid peroxidase (TPO) is an important autoantigen in Hashimoto's thyroiditis (HT),and almost all epitopes are located in TPO ectodomain.The glycosylation of TPO might contribute to breaking self-tolerance,therefore,purified glycosylated recombinant TPO ectodomain is prerequisite of elucidating its role in the pathogenesis of HT.The aim of our study was to investigate whether the glycosylation has influence on the antigenic determinants of recombinant TPO.Methods Bac-to-Bac baculovirus expression system was used to generate recombinant human TPO ectodomain.The antigenicity was analyzed by antigen specific enzyme-linked immunosorbant assays (ELISAs).The glycosylation of recombinant human TPO ectodomain of High Five insect cell origin was detected by lectin-ELISAs.Results TPO ectodomain was recovered from the culture media as a soluble protein,and it was fused with a hexahistidine tag which allowed purification by nickel-affinity chromatography.The recombinant TPO ectodomain could be recognized by all the 54 HT patients and three TPO monoclonal antibodies.Fucose,sialic acid and galactose were all detected on the recombinant TPO ectodomain.Sera TPOAb binding decreased slightly after non-specific deglycosylation of TPO by periodic acid.Conclusions High Five insect cells derived recombinant human TPO ectodomain had N-glycosylation sites,which might have little effect on recognition by serum TPOAb.

  5. A nuclear insect appears

    International Nuclear Information System (INIS)

    This book is dairy of a nuclear insect in A. F. era. It consists of 6 parts, which have fun pictures and titles. The contents are the letter that is sent the Homo sapiens by insect, exodus of nuclear insect F 100 years latter. The time that a nuclear insect is attacked in F 101, the time that a nuclear dinosaur is beat in AF 102, the time that a nuclear insect struggles in AF 104 and the time that a nuclear insect drifts in AF 104.

  6. Insect Bites and Stings

    Science.gov (United States)

    Most insect bites are harmless, though they sometimes cause discomfort. Bee, wasp, and hornet stings and fire ant bites usually hurt. Mosquito and flea bites usually itch. Insects can also spread diseases. In the United States, ...

  7. Insects: An Interdisciplinary Unit

    Science.gov (United States)

    Leger, Heather

    2007-01-01

    The author talks about an interdisciplinary unit on insects, and presents activities that can help students practice communication skills (interpersonal, interpretive, and presentational) and learn about insects with hands-on activities.

  8. Flying insects and robots

    CERN Document Server

    Ellington, Charlie

    2009-01-01

    Understanding flight mechanics of insects can aid engineers in developing intelligent flying robots. In this seminal book, biologists and engineers detail the mechanics, technology, and intelligence of insects then discuss potential benefits of their research.

  9. Rice Reoviruses in Insect Vectors.

    Science.gov (United States)

    Wei, Taiyun; Li, Yi

    2016-08-01

    Rice reoviruses, transmitted by leafhopper or planthopper vectors in a persistent propagative manner, seriously threaten the stability of rice production in Asia. Understanding the mechanisms that enable viral transmission by insect vectors is a key to controlling these viral diseases. This review describes current understanding of replication cycles of rice reoviruses in vector cell lines, transmission barriers, and molecular determinants of vector competence and persistent infection. Despite recent breakthroughs, such as the discoveries of actin-based tubule motility exploited by viruses to overcome transmission barriers and mutually beneficial relationships between viruses and bacterial symbionts, there are still many gaps in our knowledge of transmission mechanisms. Advances in genome sequencing, reverse genetics systems, and molecular technologies will help to address these problems. Investigating the multiple interaction systems among the virus, insect vector, insect symbiont, and plant during natural infection in the field is a central topic for future research on rice reoviruses. PMID:27296147

  10. Neurosecretion: peptidergic systems in insects

    Science.gov (United States)

    Predel, R.; Eckert, Manfred

    Insect neuropeptides are produced in less than 1% of the cells of the central nervous system. Despite this, they are important messenger molecules which influence nearly all physiological processes, including behaviour. They can act as transmitters, modulators and classical hormones, and often exhibit pleiotropic functions when released into the haemolymph. The large number of neuropeptides that has been identified from some of the model organisms among insects underlines the complexity of the neurosecretory system; studies about the coordinated actions of these substances are in their preliminary stages. Recent advances in insect neuropeptide research will be reviewed here, concentrating on the distribution of multiple peptide forms in the central nervous system and adjacent neurohaemal organs, and the role of neuropeptides in eclosion behaviour.

  11. Insect Barcode Information System

    OpenAIRE

    Pratheepa, Maria; Jalali, Sushil Kumar; Arokiaraj, Robinson Silvester; Venkatesan, Thiruvengadam; Nagesh, Mandadi; Panda, Madhusmita; Pattar, Sharath

    2014-01-01

    Insect Barcode Information System called as Insect Barcode Informática (IBIn) is an online database resource developed by the National Bureau of Agriculturally Important Insects, Bangalore. This database provides acquisition, storage, analysis and publication of DNA barcode records of agriculturally important insects, for researchers specifically in India and other countries. It bridges a gap in bioinformatics by integrating molecular, morphological and distribution details of agriculturally ...

  12. Exploring Sound with Insects

    Science.gov (United States)

    Robertson, Laura; Meyer, John R.

    2010-01-01

    Differences in insect morphology and movement during singing provide a fascinating opportunity for students to investigate insects while learning about the characteristics of sound. In the activities described here, students use a free online computer software program to explore the songs of the major singing insects and experiment with making…

  13. Construction and Co-expression of Grass Carp Reovirus VP6 Protein and Enhanced Green Fluorescence Protein in the Insect Cells

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Grass carp reovirus (GCRV), a disaster agent to aquatic animals, belongs to Genus Aquareovirus of family Reoviridea. Sequence analysis revealed GCRV genome segment 8 (s8) was 1296 bp nucleotides in length encoding an inner capsid protein VP6 of about 43kDa. To obtain in vitro non-fusion expression of a GCRV VP6 protein containing a molecular of fluorescence reporter, the recombinant baculovirus, which contained the GCRVs8 and eGFP (enhanced green fluorescence protein)genes, was constructed by using the Bac-to-Bac insect expression system. In this study, the whole GCRVs8 and eGFP genes, amplified by PCR, were constructed into a pFastBacDual vector under polyhedron (PH) and p10 promoters, respectively. The constructed dual recombinant plasmid (pFbDGCRVs8/eGFP) was transformed into DH10Bac cells to obtain recombinant Bacmid (AcGCRVs8/eGFP) by transposition. Finally, the recombinant bacluovirus (vAcGCRVs8/eGFP) was obtained from transfected Sf9 insect cells. The green fluorescence that was expressed by transfected Sf9 cells was initially observed 3 days post transfection, and gradually enhanced and extended around 5days culture in P1(Passage1) stock. The stable high level expression of recombinant protein was observed in P2 and subsequent passage budding virus (BV) stock. Additionally, PCR amplification from P1 and amplified P2 BV stock further confirmed the validity of the dual-recombinant baculovirus. Our results provide a foundation for expression and assembly of the GCRV structural protein in vitro.

  14. Glycoprotein H of herpes simplex virus type 1 requires glycoprotein L for transport to the surfaces of insect cells

    NARCIS (Netherlands)

    Westra, DF; Glazenburg, KL; Harmsen, MC; Tiran, A; Scheffer, AJ; Welling, GW; The, TH; WellingWester, S

    1997-01-01

    In mammalian cells, formation of heterooligomers consisting of the glycoproteins H and L (gH and gL) of herpes simplex virus type 1 is essential for the cell-to-cell spread of virions and for the penetration of virions into cells. We examined whether formation of gH1/gL1 heterooligomers and cell sur

  15. Insect Barcode Information System

    Science.gov (United States)

    Pratheepa, Maria; Jalali, Sushil Kumar; Arokiaraj, Robinson Silvester; Venkatesan, Thiruvengadam; Nagesh, Mandadi; Panda, Madhusmita; Pattar, Sharath

    2014-01-01

    Insect Barcode Information System called as Insect Barcode Informática (IBIn) is an online database resource developed by the National Bureau of Agriculturally Important Insects, Bangalore. This database provides acquisition, storage, analysis and publication of DNA barcode records of agriculturally important insects, for researchers specifically in India and other countries. It bridges a gap in bioinformatics by integrating molecular, morphological and distribution details of agriculturally important insects. IBIn was developed using PHP/My SQL by using relational database management concept. This database is based on the client– server architecture, where many clients can access data simultaneously. IBIn is freely available on-line and is user-friendly. IBIn allows the registered users to input new information, search and view information related to DNA barcode of agriculturally important insects.This paper provides a current status of insect barcode in India and brief introduction about the database IBIn. Availability http://www.nabg-nbaii.res.in/barcode PMID:24616562

  16. Establishment of a Monarch Butterfly (Danaus plexippus, Lepidoptera: Danaidae) Cell Line and its Susceptibility to Insect Viruses

    Science.gov (United States)

    A cell line from the monarch butterfly Danaus plexippus designated BCIRL-DP-AM/JG was established from adult ovaries. The cell line consisted mainly of round cells and took a prolonged period of time in the growth medium ExCell 401 containing 10% fetal bovine serum and antibiotics before it could be...

  17. Applications of genome editing in insects.

    Science.gov (United States)

    Reid, William; O'Brochta, David A

    2016-02-01

    Insect genome editing was first reported 1991 in Drosophila melanogaster but the technology used was not portable to other species. Not until the recent development of facile, engineered DNA endonuclease systems has gene editing become widely available to insect scientists. Most applications in insects to date have been technical in nature but this is rapidly changing. Functional genomics and genetics-based insect control efforts will be major beneficiaries of the application of contemporary gene editing technologies. Engineered endonucleases like Cas9 make it possible to create powerful and effective gene drive systems that could be used to reduce or even eradicate specific insect populations. 'Best practices' for using Cas9-based editing are beginning to emerge making it easier and more effective to design and use but gene editing technologies still require traditional means of delivery in order to introduce them into somatic and germ cells of insects-microinjection of developing embryos. This constrains the use of these technologies by insect scientists. Insects created using editing technologies challenge existing governmental regulatory structures designed to manage genetically modified organisms. PMID:27436552

  18. Proteomics and insect immunity

    Directory of Open Access Journals (Sweden)

    L Shi

    2006-01-01

    Full Text Available Insect innate immunity is both a model for vertebrate immunity as well as a key system that impactsmedically important pathogens that are transmitted by insects. Recent developments in proteomics andprotein identification techniques combined with the completion of genome sequences for Anophelesgambiae and Drosophila melanogaster provided the tools for examining insect immunity at a new level ofmolecular detail. Application of proteomics to insect immunity resulted in predictions of new roles inimmunity for proteins already known in other contexts (e.g. ferritin, transferrin, Chi-lectins and helped totarget specific members of multi-gene families that respond to different pathogens (e.g. serine proteases,thioester proteins. In addition, proteomics studies verify that post-translational modifications play a keyrole in insect immunity since many of the identified proteins are modified in some way. These studiescomplement recent work on insect transcriptomes and provide new directions for further investigation ofinnate immunity.

  19. The insect repellent N,N-diethyl-m-toluamide (DEET) induces angiogenesis via allosteric modulation of the M3 muscarinic receptor in endothelial cells.

    Science.gov (United States)

    Legeay, Samuel; Clere, Nicolas; Hilairet, Grégory; Do, Quoc-Tuan; Bernard, Philippe; Quignard, Jean-François; Apaire-Marchais, Véronique; Lapied, Bruno; Faure, Sébastien

    2016-01-01

    The insect repellent N,N-diethyl-m-toluamide (DEET) has been reported to inhibit AChE (acetylcholinesterase) and to possess potential carcinogenic properties with excessive vascularization. In the present paper, we demonstrate that DEET specifically stimulates endothelial cells that promote angiogenesis which increases tumor growth. DEET activates cellular processes that lead to angiogenesis including proliferation, migration and adhesion. This is associated with an enhancement of NO production and VEGF expression in endothelial cells. M3 silencing or the use of a pharmacological M3 inhibitor abrogates all of these effects which reveals that DEET-induced angiogenesis is M3 sensitive. The experiments involving calcium signals in both endothelial and HEK cells overexpressing M3 receptors, as well as binding and docking studies demonstrate that DEET acts as an allosteric modulator of the M3 receptor. In addition, DEET inhibited AChE which increased acetylcholine bioavailability and binding to M3 receptors and also strengthened proangiogenic effects by an allosteric modulation. PMID:27345502

  20. Insect immune resistance to parasitoids

    Institute of Scientific and Technical Information of China (English)

    Yves Carton; Marylène Poirié; Anthony J. Nappi

    2008-01-01

    Insect host-parasitoid interactions involve complex physiological, biochemical and genetic interactions. Against endoparasitoids, immune-competent hosts initiate a blood cell-mediated response that quickly destroys the intruders and envelops them in a multilayered melanotic capsule. During the past decade, considerable progress has been made in identifying some of the critical components of the host response, mainly because of the use of efficient molecular tools. This review examines some of the components of the innate immune response of Drosophila, an insect that has served as an exceptionally good experimental model for studying non-self recognition processes and immune cell signaling mechanisms. Topics considered in this review include hematopoiesis, proliferation and adhesion of hemocytes, melanogenesis and associated cytotoxic molecules, and the genetic aspects of the host-parasitoid interaction.

  1. Compass Cells in the Brain of an Insect Are Sensitive to Novel Events in the Visual World.

    Science.gov (United States)

    Bockhorst, Tobias; Homberg, Uwe

    2015-01-01

    The central complex of the insect brain comprises a group of neuropils involved in spatial orientation and memory. In fruit flies it mediates place learning based on visual landmarks and houses neurons that encode the orientation for goal-directed locomotion, based on landmarks and self-motion cues for angular path-integration. In desert locusts, the central complex holds a compass-like representation of head directions, based on the polarization pattern of skylight. Through intracellular recordings from immobilized locusts, we investigated whether sky compass neurons of the central complex also represent the position or any salient feature of possible landmarks, in analogy to the observations in flies. Neurons showed strongest responses to the novel appearance of a small moving square, but we found no evidence for a topographic representation of object positions. Responses to an individual square were independent of direction of motion and trajectory, but showed rapid adaptation to successive stimulation, unaffected by changing the direction of motion. Responses reappeared, however, if the moving object changed its trajectory or if it suddenly reversed moving direction against the movement of similar objects that make up a coherent background-flow as induced by ego-motion. Response amplitudes co-varied with the precedent state of dynamic background activity, a phenomenon that has been related to attention-dependent saliency coding in neurons of the mammalian primary visual cortex. The data show that neurons of the central complex of the locust brain are visually bimodal, signaling sky compass direction and the novelty character of moving objects. These response properties might serve to attune compass-aided locomotor control to unexpected events in the environment. The difference to data obtained in fruit flies might relate to differences in the lifestyle of landmark learners (fly) and compass navigators (locust), point to the existence of parallel networks for

  2. Insect cell-derived cofactors become fully functional after proteinase K and heat treatment for high-fidelity amplification of glycosylphosphatidylinositol-anchored recombinant scrapie and BSE prion proteins.

    Science.gov (United States)

    Imamura, Morikazu; Kato, Nobuko; Okada, Hiroyuki; Yoshioka, Miyako; Iwamaru, Yoshifumi; Shimizu, Yoshihisa; Mohri, Shirou; Yokoyama, Takashi; Murayama, Yuichi

    2013-01-01

    The central event in prion infection is the conformational conversion of host-encoded cellular prion protein (PrP(C)) into the pathogenic isoform (PrP(Sc)). Diverse mammalian species possess the cofactors required for in vitro replication of PrP(Sc) by protein-misfolding cyclic amplification (PMCA), but lower organisms, such as bacteria, yeasts, and insects, reportedly lack the essential cofactors. Various cellular components, such as RNA, lipids, and other identified cofactor molecules, are commonly distributed in both eukaryotes and prokaryotes, but the reasons for the absence of cofactor activity in lower organisms remain to be elucidated. Previously, we reported that brain-derived factors were necessary for the in vitro replication of glycosylphosphatidylinositol-anchored baculovirus-derived recombinant PrP (Bac-PrP). Here, we demonstrate that following protease digestion and heat treatment, insect cell lysates had the functional cofactor activity required for Bac-PrP replication by PMCA. Mammalian PrP(Sc) seeds and Bac-PrP(Sc) generated by PMCA using Bac-PrP and insect cell-derived cofactors showed similar pathogenicity and produced very similar lesions in the brains of inoculated mice. These results suggested that the essential cofactors required for the high-fidelity replication of mammalian PrP(Sc) were present in the insect cells but that the cofactor activity was masked or inhibited in the native state. We suggest that not only RNA, but also DNA, are the key components of PMCA, although other cellular factors were necessary for the expression of the cofactor activity of nucleic acids. PMCA using only insect cell-derived substances (iPMCA) was highly useful for the ultrasensitive detection of PrP(Sc) of some prion strains.

  3. Insect sodium channels and insecticide resistance

    OpenAIRE

    Dong, Ke

    2007-01-01

    Voltage-gated sodium channels are essential for the generation and propagation of action potentials (i.e., electrical impulses) in excitable cells. Although most of our knowledge about sodium channels is derived from decades of studies of mammalian isoforms, research on insect sodium channels is revealing both common and unique aspects of sodium channel biology. In particular, our understanding of the molecular dynamics and pharmacology of insect sodium channels has advanced greatly in recent...

  4. Insect Repellents: Protect Your Child from Insect Bites

    Science.gov (United States)

    ... Text Size Email Print Share Choosing an Insect Repellent for Your Child Page Content Article Body Mosquitoes , ... protect your child from insect bites. Types of Repellents Insect repellents come in many forms, including aerosols, ...

  5. Insect-cell expression, crystallization and X-ray data collection of the bradyzoite-specific antigen BSR4 from Toxoplasma gondii

    Energy Technology Data Exchange (ETDEWEB)

    Grujic, Ognjen [Biochemistry and Microbiology, University of Victoria, PO Box 3055 STN CSC, Victoria, BC, V8W 3P6 (Canada); Grigg, Michael E. [Molecular Parasitology Unit, Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 4 Center Drive, Bethesda, MD 20892 (United States); Boulanger, Martin J., E-mail: mboulang@uvic.ca [Biochemistry and Microbiology, University of Victoria, PO Box 3055 STN CSC, Victoria, BC, V8W 3P6 (Canada)

    2008-05-01

    Preliminary X-ray diffraction studies of the bradyzoite-specific surface antigen BSR4 from T. gondii are described. Toxoplasma gondii is an important global pathogen that infects nearly one third of the world’s adult population. A family of developmentally expressed structurally related surface-glycoprotein adhesins (SRSs) mediate attachment to and are utilized for entry into host cells. The latent bradyzoite form of T. gondii persists for the life of the host and expresses a distinct family of SRS proteins, of which the bradyzoite-specific antigen BSR4 is a prototypical member. Structural studies of BSR4 were initiated by first recombinantly expressing BSR4 in insect cells, which was followed by crystallization and preliminary X-ray data collection to 1.95 Å resolution. Data processing showed that BSR4 crystallized with one molecule in the asymmetric unit of the P4{sub 1}2{sub 1}2 or P4{sub 3}2{sub 1}2 space group, with a solvent content of 60% and a corresponding Matthews coefficient of 2.98 Å{sup 3} Da{sup −1}.

  6. Heterologous expression of two FAD-dependent oxidases with (S)-tetrahydroprotoberberine oxidase activity from Arge mone mexicana and Berberis wilsoniae in insect cells.

    Science.gov (United States)

    Gesell, Andreas; Chávez, Maria Luisa Díaz; Kramell, Robert; Piotrowski, Markus; Macheroux, Peter; Kutchan, Toni M

    2011-06-01

    Berberine, palmatine and dehydrocoreximine are end products of protoberberine biosynthesis. These quaternary protoberberines are elicitor inducible and, like other phytoalexins, are highly oxidized. The oxidative potential of these compounds is derived from a diverse array of biosynthetic steps involving hydroxylation, intra-molecular C-C coupling, methylenedioxy bridge formation and a dehydrogenation reaction as the final step in the biosynthesis. For the berberine biosynthetic pathway, the identification of the dehydrogenase gene is the last remaining uncharacterized step in the elucidation of the biosynthesis at the gene level. An enzyme able to catalyze these reactions, (S)-tetrahydroprotoberberine oxidase (STOX, EC 1.3.3.8), was originally purified in the 1980s from suspension cells of Berberis wilsoniae and identified as a flavoprotein (Amann et al. 1984). We report enzymatic activity from recombinant STOX expressed in Spodoptera frugiperda Sf9 insect cells. The coding sequence was derived successively from peptide sequences of purified STOX protein. Furthermore, a recombinant oxidase with protoberberine dehydrogenase activity was obtained from a cDNA library of Argemone mexicana, a traditional medicinal plant that contains protoberberine alkaloids. The relationship of the two enzymes is discussed regarding their enzymatic activity, phylogeny and the alkaloid occurrence in the plants. Potential substrate binding and STOX-specific amino acid residues were identified based on sequence analysis and homology modeling.

  7. Insects and Bugs

    Science.gov (United States)

    Sutherland, Karen

    2009-01-01

    They have been around for centuries. They sting, they bite. They cause intense itching or painful sores. They even cause allergic reactions and sometimes death. There are two types of insects that are pests to humans--those that sting and those that bite. The insects that bite do so with their mouths and include mosquitoes, chiggers, and ticks.…

  8. Insects: Bugged Out!

    Science.gov (United States)

    Piehl, Kathy

    2011-01-01

    Insects really need no introduction. They have lived on earth much longer than humans and vastly outnumber people and all other animal species combined. People encounter them daily in their houses and yards. Yet, when children want to investigate insects, books can help them start their explorations. "Paleo Bugs" carries readers back to the time…

  9. Insect bites and stings

    Science.gov (United States)

    ... likely to cause itching than pain. Insect and spider bites cause more deaths from venom reactions than bites from snakes. ... are harmless. If possible, bring the insect or spider that bit you with you when you go for medical treatment so it can be identified.

  10. Reversing insect pollinator decline

    OpenAIRE

    Potts, Simon; Wentworth, Jonathan

    2013-01-01

    Pollination by insects enables the reproduction of flowering plants and is critical to UK agriculture.1 Insect pollinators have declined globally, with implications for food security and wild habitats. This POSTnote summarises the causes for the recent trends, gaps in knowledge and possible strategies for reversing pollinator decline.

  11. Sterile insect quality

    International Nuclear Information System (INIS)

    The sterile insect technique (SIT) depends greatly on the production of good quality sterile male insects that are released into target wild populations. Quality is assured through a system of bioassays of quality parameters that reflect the insect's ability to survive, interact with its environment, and locate, mate and fertilize females of the target population. The system was developed by compartmentalizing the essential survival and mating behaviours of the species involved, and then developing a series of tests to confirm that these behavioural traits are present in the mass-reared insects. The system also has a feedback loop to correct problems in the production portion of the system before they become evident. Nevertheless, regular implementation of field or field-cage tests under semi-natural conditions, where sterile males have to compete with wild males for wild females, is required to provide the ultimate assurance that the sterile insects have the ability to fulfil their mission after release. (author)

  12. Studies of the intermediary metabolism in cultured cells of the insect Spodoptera frugiperda using 13C- or 15N-labelled tracers

    Directory of Open Access Journals (Sweden)

    Bacher Adelbert

    2005-11-01

    Full Text Available Abstract Background Insect cells can serve as host systems for the recombinant expression of eukaryotic proteins. Using this platform, the controlled expression of 15N/13C labelled proteins requires the analysis of incorporation paths and rates of isotope-labelled precursors present in the medium into amino acids. For this purpose, Spodoptera frugiperda cells were grown in a complex medium containing [U-13C6]glucose. In a second experiment, cultures of S. frugiperda were grown in the presence of 15N-phenylalanine. Results Quantitative NMR analysis showed incorporation of the proffered [U-13C6]glucose into the ribose moiety of ribonucleosides (40 – 45% and into the amino acids, alanine (41%, glutamic acid/glutamine (C-4 and C-5, 30% and aspartate/asparagine (15%. Other amino acids and the purine ring of nucleosides were not formed from exogenous glucose in significant amounts (> 5%. Prior to the incorporation into protein the proffered 15N-phenylalanine lost about 70% of its label by transamination and the labelled compound was not converted into tyrosine to a significant extent. Conclusion Growth of S. frugiperda cells in the presence of [U-13C6]glucose is conducive to the fractional labelling of ribonucleosides, alanine, glutamic acid/glutamine and aspartic acid/asparagine. The isotopolog compositions of the ribonucleosides and of alanine indicate considerable recycling of carbohydrate intermediates in the reductive branch of the pentose phosphate pathway. The incorporation of 15N-labelled amino acids may be hampered by loss of the 15N-label by transamination.

  13. Endogenous chloride channels of insect sf9 cells. Evidence for coordinated activity of small elementary channel units

    DEFF Research Database (Denmark)

    Larsen, Erik Hviid; Gabriel, S. E.; Stutts, M. J.;

    1996-01-01

    -cell current fluctuations. Chloride channels exhibited multiple conductance states with similar Goldman-Hodgkin-Katz-type rectification. Single-channel permeabilities covered the range from approximately 0.6.10(-14) cm5/s to approximately 6.10(-14) cm3/s, corresponding to a limiting conductance (gamma 150...

  14. Two Novel 30K Proteins Overexpressed in Baculovirus System and Their Antiapoptotic Effect in Insect and Mammalian Cells

    Directory of Open Access Journals (Sweden)

    Wei Yu

    2013-01-01

    Full Text Available The 30K family of proteins is important in energy metabolism and may play a role in inhibiting cellular apoptosis in silkworms (Bombyx mori. Several 30K-family proteins have been identified. In this study, two new silkworm genes, referred to as Slp (NM 001126256 and Lsp-t (NM 001043443, were analyzed by a bioinformatics approach according to the sequences of 30K proteins previously reported in the silkworm. Both Slp and Lsp-t shared more than 41% amino acid sequence homology with the reported 30K proteins and displayed a conserved domain consistent with that of lipoprotein-11. Additionally, the cDNA sequences of both Slp and Lsp-t were obtained from the fat bodies of silkworm larvae by reverse transcription polymerase chain reaction. Both genes were expressed in BmN cells using the Bac-to-Bac system. Purified Slp and Lsp-t were added to cultured BmN and human umbilical vein endothelial cells (HUVEC that were treated with H2O2. Both Slp and Lsp-t significantly enhanced the viability and suppressed DNA fragmentation in H2O2 treated BmN and HUVEC cells. This study suggested that Slp and Lsp-t exhibit similar biological activities as their known 30K-protein counterparts and mediate an inhibitory effect against H2O2-induced apoptosis.

  15. Apolipophorins and insects immune response

    Directory of Open Access Journals (Sweden)

    A Zdybicka-Barabas

    2013-08-01

    Full Text Available Insect lipoproteins, called lipophorins, are non-covalent assemblies of lipids and proteins serving as lipid transport vehicles. The protein moiety of lipophorin comprises two glycosylated apolipoproteins, apolipophorin I (apoLp-I and apolipophorin II (apoLp-II, constantly present in a lipophorin particle, and an exchangeable protein, apolipophorin III (apoLp-III. ApoLp-III is an abundant protein occurring in hemolymph in lipid-free and lipid-bound state and playing an important role in lipid transport and insect innate immunity. In immune response apoLp-III serves as a pattern recognition molecule. It binds and detoxifies microbial cell wall components, i.e., lipopolysaccharide, lipoteichoic acid, and β-1,3-glucan. ApoLp-III activates expression of antimicrobial peptides and proteins, stimulates their antimicrobial activity, participates in regulation of the phenoloxidase system and in hemolymph clotting. In addition, the protein is involved in cellular immune response, influencing hemocyte adhesion, phagocytosis and nodule formation, and in gut immunity. Although apoLp-III is the best studied apolipophorin in insect immunity so far, a literature review suggests that all the three apolipoproteins, apoLp-I, apoLp-II and apoLp-III, function together in a coordinated defense against pathogens

  16. The insect cellular immune response

    Institute of Scientific and Technical Information of China (English)

    Michael R. Strand

    2008-01-01

    The innate immune system of insects is divided into humoral defenses that include the production of soluble effector molecules and cellular defenses like phagocytosis and encapsulation that are mediated by hemocytes. This review summarizes current understanding of the cellular immune response. Insects produce several terminally differentiated types of hemocytes that are distinguished by morphology, molecular and antigenic markers, and function. The differentiated hemocytes that circulate in larval or nymphal stage insects arise from two sources: progenitor cells produced during embryogenesis and mesodermally derived hematopoietic organs. Regulation of hematopoiesis and hemocyte differentiation also involves several different signaling pathways. Phagocytosis and encapsulation require that hemocytes first recognize a given target as foreign followed by activation of downstream signaling and effector responses. A number of humoral and cellular receptors have been identified that recognize different microbes and multicellular parasites. In turn, activation of these receptors stimulates a number of signaling pathways that regulate different hemocyte functions. Recent studies also identify hemocytes as important sources of a number of humoral effector molecules required for killing different foreign invaders.

  17. Expression of a bee venom phospholipase A2 from Apis cerana cerana in the baculovirus-insect cell*

    OpenAIRE

    Shen, Li-rong; Ding, Mei-hui; Li-wen ZHANG; Zhang, Wei-Guang; Liu, Liang; Li, Duo

    2010-01-01

    Bee venom phospholipase A2 (BvPLA2) is a lipolytic enzyme that catalyzes the hydrolysis of the sn-2 acyl bond of glycerophospholipids to liberate free fatty acids and lysophospholipids. In this work, a new BvPLA2 (AccPLA2) gene from the Chinese honeybee (Apis cerana cerana) venom glands was inserted into bacmid to construct a recombinant transfer vector. Tn-5B-4 (Tn) cells were transfected with the recombinant bacmid DNA for expression. Sodium dodecylsulfate-polyacrylamide gel electrophoresis...

  18. Large-scale production and purification of recombinant protein from an insect cell/baculovirus system in Erlenmeyer flasks: application to the chicken poly(ADP-ribose polymerase catalytic domain

    Directory of Open Access Journals (Sweden)

    Miranda E.A.

    1997-01-01

    Full Text Available A simple and inexpensive shaker/Erlenmeyer flask system for large-scale cultivation of insect cells is described and compared to a commercial spinner system. On the basis of maximum cell density, average population doubling time and overproduction of recombinant protein, a better result was obtained with a simpler and less expensive bioreactor consisting of Erlenmeyer flasks and an ordinary shaker waterbath. Routinely, about 90 mg of pure poly(ADP-ribose polymerase catalytic domain was obtained for a total of 3 x 109 infected cells in three liters of culture

  19. Roles of the Laodelphax striatellus Down syndrome cell adhesion molecule in Rice stripe virus infection of its insect vector.

    Science.gov (United States)

    Zhang, F; Li, Q; Chen, X; Huo, Y; Guo, H; Song, Z; Cui, F; Zhang, L; Fang, R

    2016-08-01

    The arthropod Down syndrome cell adhesion molecule (Dscam) mediates pathogen-specific recognition via an extensive protein isoform repertoire produced by alternative splicing. To date, most studies have focused on the subsequent pathogen-specific immune response, and few have investigated the entry into cells of viruses or endosymbionts. In the present study, we cloned and characterized the cDNA of Laodelphax striatellus Dscam (LsDscam) and investigated the function of LsDscam in rice stripe virus (RSV) infection and the influence on the endosymbiont Wolbachia. LsDscam displayed a typical Dscam domain architecture, including 10 immunoglobulin (Ig) domains, six fibronectin type III domains, one transmembrane domain and a cytoplasmic tail. Alternative splicing occurred at the N-termini of the Ig2 and Ig3 domains, the complete Ig7 domain, the transmembrane domain and the C-terminus, comprising 10, 51, 35, two and two variable exons, respectively. Potentially LsDscam could encode at least 71 400 unique isoforms and 17 850 types of extracellular regions. LsDscam was expressed in various L. striatellus tissues. Knockdown of LsDscam mRNA via RNA interference decreased the titres of both RSV and Wolbachia, but did not change the numbers of the extracellular symbiotic bacterium Acinetobacter rhizosphaerae. Specific Dscam isoforms may play roles in enhancing the infection of vector-borne viruses or endosymbionts. PMID:26991800

  20. Evolution of the Insects

    Science.gov (United States)

    Grimaldi, David; Engel, Michael S.

    2005-05-01

    This book chronicles the complete evolutionary history of insects--their living diversity and relationships as well as 400 million years of fossils. Introductory sections cover the living species diversity of insects, methods of reconstructing evolutionary relationships, basic insect structure, and the diverse modes of insect fossilization and major fossil deposits. Major sections then explore the relationships and evolution of each order of hexapods. The volume also chronicles major episodes in the evolutionary history of insects from their modest beginnings in the Devonian and the origin of wings hundreds of millions of years before pterosaurs and birds to the impact of mass extinctions and the explosive radiation of angiosperms on insects, and how they evolved into the most complex societies in nature. Whereas other volumes focus on either living species or fossils, this is the first comprehensive synthesis of all aspects of insect evolution. Illustrated with 955 photo- and electron- micrographs, drawings, diagrams, and field photos, many in full color and virtually all of them original, this reference will appeal to anyone engaged with insect diversity--professional entomologists and students, insect and fossil collectors, and naturalists. David Grimaldi and Michael S. Engel have collectively published over 200 scientific articles and monographs on the relationships and fossil record of insects, including 10 articles in the journals Science, Nature, and Proceedings of the National Academy of Sciences. David Grimaldi is curator in the Division of Invertebrate Zoology, American Museum of Natural History and adjunct professor at Cornell University, Columbia University, and the City University of New York. David Grimaldi has traveled in 40 countries on 6 continents, collecting and studying recent species of insects and conducting fossil excavations. He is the author of Amber: Window to the Past (Abrams, 2003). Michael S. Engel is an assistant professor in the

  1. INSECT FLIGHT - BIOACOUSTICAL APPROACH

    OpenAIRE

    Gopala Krishna, G.; Krishna Shankar, B.; Ahmad, A.

    1990-01-01

    Insect aerodynamics is drawing the attention of a number of researchers belonging to different disciplines with a view to understand its aerodynamic capabilities so as to revolutionise the aircraft technology. It is possible to understand, to some extent, the insect aerodynamics by experimentally determining the frequency of wing beat in its fethered state of flight by using flight sound technique and computing rate of mass flow, velocity, acceleration and mass of air induced in downward dire...

  2. Important Insect Pests of Fruit - Important Insect Pests of Nuts - Field Crop Insect Pests - Insect Pests of Vegetable Crops.

    Science.gov (United States)

    Gesell, Stanley G.; And Others

    This document consists of four agriculture extension service publications from Pennsylvania State University. The titles are: (1) Important Insect Pests of Fruit; (2) Important Insect Pests of Nuts; (3) Field Crop Insect Pests; and (4) Insect Pests of Vegetable Crops. The first publication gives the hosts, injury, and description of 22 insect…

  3. The promise of insect genomics

    DEFF Research Database (Denmark)

    Grimmelikhuijzen, Cornelis J P; Cazzamali, Giuseppe; Williamson, Michael;

    2007-01-01

    Insects are the largest animal group in the world and are ecologically and economically extremely important. This importance of insects is reflected by the existence of currently 24 insect genome projects. Our perspective discusses the state-of-the-art of these genome projects and the impacts...... that they have on basic insect science and pest control....

  4. Purification and characterization of recombinant sugarcane sucrose phosphate synthase expressed in E. coli and insect Sf9 cells: an importance of the N-terminal domain for an allosteric regulatory property.

    Science.gov (United States)

    Sawitri, Widhi Dyah; Narita, Hirotaka; Ishizaka-Ikeda, Etsuko; Sugiharto, Bambang; Hase, Toshiharu; Nakagawa, Atsushi

    2016-06-01

    Sucrose phosphate synthase (SPS) catalyses the transfer of glycosyl group of uridine diphosphate glucose to fructose-6-phosphate to form sucrose-6-phosphate. Plant SPS plays a key role in photosynthetic carbon metabolisms, which activity is modulated by an allosteric activator glucose-6-phosphate (G6P). We produced recombinant sugarcane SPS using Escherichia coli and Sf9 insect cells to investigate its structure-function relationship. When expressed in E. coli, two forms of SPS with different sizes appeared; the larger was comparable in size with the authentic plant enzyme and the shorter was trimmed the N-terminal 20 kDa region off. In the insect cells, only enzyme with the authentic size was produced. We purified the trimmed SPS and the full size enzyme from insect cells and found their enzymatic properties differed significantly; the full size enzyme was activated allosterically by G6P, while the trimmed one showed a high activity even without G6P. We further introduced a series of N-terminal truncations up to 171 residue and found G6P-independent activity was enhanced by the truncation. These combined results indicated that the N-terminal region of sugarcane SPS is crucial for the allosteric regulation by G6P and may function like a suppressor domain for the enzyme activity. PMID:26826371

  5. Analysis of the genome of the sexually transmitted insect virus Hz-2V

    Science.gov (United States)

    Hz-2V is an insect DNA virus closely related to the baculoviruses that grow to high titers in insect cells and produces high yields of virus progeny. The capacity of this virus to replicate to high titers in insect cells may allow the use of this virus for production of large amount of proteins. Th...

  6. Insect immunology and hematopoiesis.

    Science.gov (United States)

    Hillyer, Julián F

    2016-05-01

    Insects combat infection by mounting powerful immune responses that are mediated by hemocytes, the fat body, the midgut, the salivary glands and other tissues. Foreign organisms that have entered the body of an insect are recognized by the immune system when pathogen-associated molecular patterns bind host-derived pattern recognition receptors. This, in turn, activates immune signaling pathways that amplify the immune response, induce the production of factors with antimicrobial activity, and activate effector pathways. Among the immune signaling pathways are the Toll, Imd, Jak/Stat, JNK, and insulin pathways. Activation of these and other pathways leads to pathogen killing via phagocytosis, melanization, cellular encapsulation, nodulation, lysis, RNAi-mediated virus destruction, autophagy and apoptosis. This review details these and other aspects of immunity in insects, and discusses how the immune and circulatory systems have co-adapted to combat infection, how hemocyte replication and differentiation takes place (hematopoiesis), how an infection prepares an insect for a subsequent infection (immune priming), how environmental factors such as temperature and the age of the insect impact the immune response, and how social immunity protects entire groups. Finally, this review highlights some underexplored areas in the field of insect immunobiology. PMID:26695127

  7. Solubility as a limiting factor for expression of hepatitis A virus proteins in insect cell-baculovirus system.

    Science.gov (United States)

    Silva, Haroldo Cid da; Pestana, Cristiane Pinheiro; Galler, Ricardo; Medeiros, Marco Alberto

    2016-08-01

    The use of recombinant proteins may represent an alternative model to inactivated vaccines against hepatitis A virus (HAV). The present study aimed to express the VP1 protein of HAV in baculovirus expression vector system (BEVS). The VP1 was expressed intracellularly with molecular mass of 35 kDa. The VP1 was detected both in the soluble fraction and in the insoluble fraction of the lysate. The extracellular expression of VP1 was also attempted, but the protein remained inside the cell. To verify if hydrophobic characteristics would also be present in the HAV structural polyprotein, the expression of P1-2A protein was evaluated. The P1-2A polyprotein remained insoluble in the cellular extract, even in the early infection stages. These results suggest that HAV structural proteins are prone to form insoluble aggregates. The low solubility represents a drawback for production of large amounts of HAV proteins in BEVS. PMID:27581123

  8. Advances in the preservation of insect germplasm

    International Nuclear Information System (INIS)

    The current means of preserving insects that are freezing intolerant or have no dormancy capabilities for use in the laboratory or in management programmes is by continuous culture. Not only can continuous culture be a costly venture, but it can effect genetic drift and is subject to accidental loss of colonies, genetic strains and transformants. Further, the ability to be able to stockpile insects for later use in sterile insect technique and biocontrol programmes would be of tremendous benefit. Since preservation of mammalian embryos by low temperature technology has become a common procedure, researchers, insectary managers and those involved in control programmes have been looking to cryobiologists for assistance in solving the insect germplasm storage problem. The paper examines the concepts of the conventional methodology that is used for cryopreservation of cells and mammalian embryos. Also pointed out are several inherent barriers posed by embryos of insects such as muscoid flies which are incompatible with the use of the conventional techniques. Of the obstacles thus far identified, chilling intolerance and egg membrane impermeability have been given the most attention by researchers attempting to develop low temperature storage methods. Limited but promising success has been obtained using chemical dissolution of membrane waxes, infusion of embryos with multimoral cryoprotectants and avoidance of chilling injury by ultrarapid cooling and warming. The feasibility of incorporating techniques which facilitate natural insect cold hardiness into a cryopreservation protocol and alternatives to preservation of embryos are discussed. (author). 53 refs, 4 figs, 1 tab

  9. Are edible insects really green?

    OpenAIRE

    Caparros Megido, Rudy; Alabi, Taofic; Haubruge, Eric; Francis, Frédéric

    2015-01-01

    Edible insects are considered as one of the future and sustainable sources of animal protein. Insects for food or feed could have several origins. In Asia, Africa, South America or Oceania, the diversity of edible insects is very high (approximately 2000 species) and these insects are principally collected from the wild or semi-cultivated. However, in Western countries, entomophagy promoters rely on a few numbers of insect species (approximately 10 species) and on the development of industria...

  10. Damage signals in the insect immune response

    Directory of Open Access Journals (Sweden)

    Robert eKrautz

    2014-07-01

    Full Text Available Insects and mammals share an ancient innate immune system comprising both humoral and cellular responses. The insect immune system consists of the fat body, which secretes effector molecules into the hemolymph and several classes of hemocytes, which reside in the hemolymph and of protective border epithelia. Key features of wound- and immune responses are shared between insect and mammalian immune systems including the mode of activation by commonly shared microbial (nonself patterns and the recognition of these patterns by dedicated receptors. It is unclear how metazoan parasites in insects, which lack these shared motifs, are recognized. Research in recent years has demonstrated that during entry into the insect host, many eukaryotic pathogens leave traces that alert potential hosts of the damage they have afflicted. In accordance with terminology used in the mammalian immune systems, these signals have been dubbed danger- or damage-associated signals. Damage signals are necessary byproducts generated during entering hosts either by mechanical or proteolytic damage. Here, we briefly review the current stage of knowledge on how wound closure and wound healing during mechanical damage is regulated and how damage-related signals contribute to these processes. We also discuss how sensors of proteolytic activity induce insect innate immune responses. Strikingly damage-associated signals are also released from cells that have aberrant growth, including tumor cells. These signals may induce apoptosis in the damaged cells, the recruitment of immune cells to the aberrant tissue and even activate humoral responses. Thus, this ensures the removal of aberrant cells and compensatory proliferation to replace lost tissue. Several of these pathways may have been co-opted from wound healing and developmental processes.

  11. Insect bite reactions

    Directory of Open Access Journals (Sweden)

    Sanjay Singh

    2013-01-01

    Full Text Available Insects are a class of living creatures within the arthropods. Insect bite reactions are commonly seen in clinical practice. The present review touches upon the medically important insects and their places in the classification, the sparse literature on the epidemiology of insect bites in India, and different variables influencing the susceptibility of an individual to insect bites. Clinical features of mosquito bites, hypersensitivity to mosquito bites Epstein-Barr virus NK (HMB-EBV-NK disease, eruptive pseudoangiomatosis, Skeeter syndrome, papular pruritic eruption of HIV/AIDS, and clinical features produced by bed bugs, Mexican chicken bugs, assassin bugs, kissing bugs, fleas, black flies, Blandford flies, louse flies, tsetse flies, midges, and thrips are discussed. Brief account is presented of the immunogenic components of mosquito and bed bug saliva. Papular urticaria is discussed including its epidemiology, the 5 stages of skin reaction, the SCRATCH principle as an aid in diagnosis, and the recent evidence supporting participation of types I, III, and IV hypersensitivity reactions in its causation is summarized. Recent developments in the treatment of pediculosis capitis including spinosad 0.9% suspension, benzyl alcohol 5% lotion, dimethicone 4% lotion, isopropyl myristate 50% rinse, and other suffocants are discussed within the context of evidence derived from randomized controlled trials and key findings of a recent systematic review. We also touch upon a non-chemical treatment of head lice and the ineffectiveness of egg-loosening products. Knockdown resistance (kdr as the genetic mechanism making the lice nerves insensitive to permethrin is discussed along with the surprising contrary clinical evidence from Europe about efficacy of permethrin in children with head lice carrying kdr-like gene. The review also presents a brief account of insects as vectors of diseases and ends with discussion of prevention of insect bites and some

  12. Modeling and simulation of anion-exchange membrane chromatography for purification of Sf9 insect cell-derived virus-like particles.

    Science.gov (United States)

    Ladd Effio, Christopher; Hahn, Tobias; Seiler, Julia; Oelmeier, Stefan A; Asen, Iris; Silberer, Christine; Villain, Louis; Hubbuch, Jürgen

    2016-01-15

    Recombinant protein-based virus-like particles (VLPs) are steadily gaining in importance as innovative vaccines against cancer and infectious diseases. Multiple VLPs are currently evaluated in clinical phases requiring a straightforward and rational process design. To date, there is no generic platform process available for the purification of VLPs. In order to accelerate and simplify VLP downstream processing, there is a demand for novel development approaches, technologies, and purification tools. Membrane adsorbers have been identified as promising stationary phases for the processing of bionanoparticles due to their large pore sizes. In this work, we present the potential of two strategies for designing VLP processes following the basic tenet of 'quality by design': High-throughput experimentation and process modeling of an anion-exchange membrane capture step. Automated membrane screenings allowed the identification of optimal VLP binding conditions yielding a dynamic binding capacity of 5.7 mg/mL for human B19 parvovirus-like particles derived from Spodoptera frugiperda Sf9 insect cells. A mechanistic approach was implemented for radial ion-exchange membrane chromatography using the lumped-rate model and stoichiometric displacement model for the in silico optimization of a VLP capture step. For the first time, process modeling enabled the in silico design of a selective, robust and scalable process with minimal experimental effort for a complex VLP feedstock. The optimized anion-exchange membrane chromatography process resulted in a protein purity of 81.5%, a DNA clearance of 99.2%, and a VLP recovery of 59%. PMID:26718185

  13. Migration strategies of insects.

    Science.gov (United States)

    Dingle, H

    1972-03-24

    Physiological and ecological results from a variety of species are consistent with what seem to be valid general statements concerning insect migration. These are as follows: (i)During migration locomotory functions are enhanced and vegetative functions such as feeding and reproduction are suppressed. (ii) Migration usually occurs prereproductively in the life of the adult insect (the oogenesis-flight syndrome). (iii)Since migrant individuals are usually prereproductive, their reproductive values, and hence colonizing abilities, are at or near maximum. (iv) Migrants usually reside in temporary habitats. (v)Migrants have a high potential for population increase, r, which is also advantageous for colonizers. (vi)Both the physiological and ecological parameters of migration are modifiable by environmental factors (that is, phenotypically modifiable)to suit the prevailing conditions. Taken together, these criteria establish a comprehensive theory and adumbrate the basic strategy for migrant insects. This basic strategy is modified to suit the ecological requirements of individual species. Comparative studies of these modifications are of considerable theoretical and practical interest, the more so since most economically important insects are migrants. No satisfactory general statements can as yet be made with respect to the genotype and migration. Certainly we expect colonizing populiations to possess genotypes favoring a high r, but genotypic variation in r depends on the heritabilities of life table statistics, and such measurements are yet to be made (10, 53). The fact that flight duration can be increased by appropriate selection in Oncopeltus fasciatus, and the demonstration of additive genetic variance for this trait in Lygaeus kalmii, suggest that heritability studies of migratory behavior would also be worth pursuing. Most interesting of course, will be possible genetic correlations between migration and life history parameters. Also, migration often

  14. Palmitoylation of the GluR6 kainate receptor.

    OpenAIRE

    Pickering, D S; Taverna, F A; Salter, M W; Hampson, D.R.

    1995-01-01

    The G-protein-coupled metabotropic glutamate receptor mGluR1 alpha and the ionotropic glutamate receptor GluR6 were examined for posttranslational palmitoylation. Recombinant receptors were expressed in baculovirus-infected insect cells or in human embryonic kidney cells and were metabolically labeled with [3H]palmitic acid. The metabotropic mGluR1 alpha receptor was not labeled whereas the GluR6 kainate receptor was labeled after incubation with [3H]palmitate. The [3H]palmitate labeling of G...

  15. Distribution of the Primary Endosymbiont (Candidatus Uzinura Diaspidicola Within Host Insects from the Scale Insect Family Diaspididae

    Directory of Open Access Journals (Sweden)

    Katharina Dittmar

    2012-02-01

    Full Text Available It has long been known that armored scale insects harbor endosymbiotic bacteria inside specialized cells called bacteriocytes. Originally, these endosymbionts were thought to be fungal symbionts but they are now known to be bacterial and have been named Uzinura diaspidicola. Bacteriocyte and endosymbiont distribution patterns within host insects were visualized using in situ hybridization via 16S rRNA specific probes. Images of scale insect embryos, eggs and adult scale insects show patterns of localized bacteriocytes in embryos and randomly distributed bacteriocytes in adults. The symbiont pocket was not found in the armored scale insect eggs that were tested. The pattern of dispersed bacteriocytes in adult scale insects suggest that Uzinura and Blattabacteria may share some homologous traits that coincide with similar life style requirements, such as dispersal in fat bodies and uric acid recycling.

  16. Distribution of the Primary Endosymbiont (Candidatus Uzinura Diaspidicola) Within Host Insects from the Scale Insect Family Diaspididae.

    Science.gov (United States)

    Gruwell, Matthew E; Flarhety, Meghan; Dittmar, Katharina

    2012-01-01

    It has long been known that armored scale insects harbor endosymbiotic bacteria inside specialized cells called bacteriocytes. Originally, these endosymbionts were thought to be fungal symbionts but they are now known to be bacterial and have been named Uzinura diaspidicola. Bacteriocyte and endosymbiont distribution patterns within host insects were visualized using in situ hybridization via 16S rRNA specific probes. Images of scale insect embryos, eggs and adult scale insects show patterns of localized bacteriocytes in embryos and randomly distributed bacteriocytes in adults. The symbiont pocket was not found in the armored scale insect eggs that were tested. The pattern of dispersed bacteriocytes in adult scale insects suggest that Uzinura and Blattabacteria may share some homologous traits that coincide with similar life style requirements, such as dispersal in fat bodies and uric acid recycling.

  17. The Sterile Insect Technique

    International Nuclear Information System (INIS)

    Insect pests have caused an increasing problem in agriculture and human health through crop losses and disease transmission to man and livestock. Intervention to ensure food security and human health has relied on Integrated Pest Management (IPM) strategies to keep the pests population below economic injury levels. IPM integrate a variety of methods, but there has been over-reliance on chemical control following the discovery of insecticidal properties of DDT. It is now realized that, maintaining pest populations at controlled levels is unsustainable and eradication options is now being considered. Although the Sterile Insect Technique(SIT) could be used for insect suppression, it is gaining favour in the elimination (eradication) of the target pest population through Areawide-based IPM (Author)

  18. Behavioral Immunity in Insects

    Directory of Open Access Journals (Sweden)

    Thierry Lefèvre

    2012-08-01

    Full Text Available Parasites can dramatically reduce the fitness of their hosts, and natural selection should favor defense mechanisms that can protect hosts against disease. Much work has focused on understanding genetic and physiological immunity against parasites, but hosts can also use behaviors to avoid infection, reduce parasite growth or alleviate disease symptoms. It is increasingly recognized that such behaviors are common in insects, providing strong protection against parasites and parasitoids. We review the current evidence for behavioral immunity in insects, present a framework for investigating such behavior, and emphasize that behavioral immunity may act through indirect rather than direct fitness benefits. We also discuss the implications for host-parasite co-evolution, local adaptation, and the evolution of non-behavioral physiological immune systems. Finally, we argue that the study of behavioral immunity in insects has much to offer for investigations in vertebrates, in which this topic has traditionally been studied.

  19. Sterile insect technique and radiation in insect control

    International Nuclear Information System (INIS)

    Out of 39 papers and 6 summaries of the poster presentations published in this proceeding series, 23 respectively fall within the INIS subject scope. Four main topics were covered: a review of the sterile insect technique against various insect pests; its application to tsetse flies in eradication programmes; quality control of mass-reared insects for release; and the development of genetic approaches to insect mass rearing and control. Other topics emphasized integrated pest management, computer models and radioisotope labelling

  20. Insects, isotopes and radiations

    International Nuclear Information System (INIS)

    The IAEA activity on coordinating the IAEA member-state efforts in the field of pest control is considered. A complex program of agricultural pest control (IPM), applied in many parts of the world is developed. The program provides for the use of natural means of control and cases of critical pest numbers-the use of insecticides. When controlling certain types of insects it is advisable to apply the 'large area control' methods which provide for the insect destruction in places of their concentration prior to migration. Methods of pest control over large areas also include radiation sexual sterilization method (SSM), application of insect phoromons (sexual attractants) to prevent mating, other types of chemical attractants, traps, mass cultivation and reproduction of parasite plants and animals, destroying insects, as well as improvement of host-plant resistance. A great attention is paid to isotope and radiation application in pest control (labelling, sexual sterilization using ionising radiation, radiation application in genetic engineering, mutant plant cultivation)

  1. Broadening insect gastronomy

    DEFF Research Database (Denmark)

    Halloran, Afton Marina Szasz; Münke, Christopher; Vantomme, Paul;

    2015-01-01

    In recent years there has been a trend among chefs to diversify their ingredients and techniques, drawing inspiration from other cultures and creating new foods by blending this knowledge with the flavours of their local region. Edible insects, with their plethora of taste, aromatic, textural and...

  2. Olfactory signaling in insects.

    Science.gov (United States)

    Wicher, Dieter

    2015-01-01

    The detection of volatile chemical information in insects is performed by three types of olfactory receptors, odorant receptors (ORs), specific gustatory receptor (GR) proteins for carbon dioxide perception, and ionotropic receptors (IRs) which are related to ionotropic glutamate receptors. All receptors form heteromeric assemblies; an OR complex is composed of an odor-specific OrX protein and a coreceptor (Orco). ORs and GRs have a 7-transmembrane topology as for G protein-coupled receptors, but they are inversely inserted into the membrane. Ligand-gated ion channels (ionotropic receptors) and ORs operate as IRs activated by volatile chemical cues. ORs are evolutionarily young receptors, and they first appear in winged insects and seem to be evolved to allow an insect to follow sparse odor tracks during flight. In contrast to IRs, the ORs can be sensitized by repeated subthreshold odor stimulation. This process involves metabotropic signaling. Pheromone receptors are especially sensitive and require an accessory protein to detect the lipid-derived pheromone molecules. Signaling cascades involved in pheromone detection depend on intensity and duration of stimuli and underlie a circadian control. Taken together, detection and processing of volatile information in insects involve ionotropic as well as metabotropic mechanisms. Here, I review the cellular signaling events associated with detection of cognate ligands by the different types of odorant receptors.

  3. Recycled Insect Models

    Science.gov (United States)

    Rule, Audrey C.; Meyer, Mary Ann

    2007-01-01

    This article presents an engaging activity in which high school students use a dichotomous key to guide the creation and classification of model insects from recycled plastic lids and containers. Besides teaching the use of a dichotomous key and the effect of evolutionary descent upon groupings of organisms, this activity focuses on an…

  4. Colour constancy in insects.

    Science.gov (United States)

    Chittka, Lars; Faruq, Samia; Skorupski, Peter; Werner, Annette

    2014-06-01

    Colour constancy is the perceptual phenomenon that the colour of an object appears largely unchanged, even if the spectral composition of the illuminating light changes. Colour constancy has been found in all insect species so far tested. Especially the pollinating insects offer a remarkable opportunity to study the ecological significance of colour constancy since they spend much of their adult lives identifying and choosing between colour targets (flowers) under continuously changing ambient lighting conditions. In bees, whose colour vision is best studied among the insects, the compensation provided by colour constancy is only partial and its efficiency depends on the area of colour space. There is no evidence for complete 'discounting' of the illuminant in bees, and the spectral composition of the light can itself be used as adaptive information. In patchy illumination, bees adjust their spatial foraging to minimise transitions between variously illuminated zones. Modelling allows the quantification of the adaptive benefits of various colour constancy mechanisms in the economy of nature. We also discuss the neural mechanisms and cognitive operations that might underpin colour constancy in insects. PMID:24647930

  5. Insect Resistant Maize 5307

    OpenAIRE

    Directorate, Issued by Health Canada's Food

    2014-01-01

    Health Canada has notified Syngenta Seeds Canada Inc. that it has no objection to the sale of food derived from Insect Resistant Maize 5307. The Department conducted a comprehensive assessment of this corn event according to its Guidelines for the Safety Assessment of Novel Foods. These Guidelines are based upon internationally accepted principles for establishing the safety of foods with novel traits.

  6. Sterol metabolism of insects

    NARCIS (Netherlands)

    Ritter, F.J.; Wientjens, W.H.J.M.

    1967-01-01

    This article surveys the present knowledge of the sterol metabolism of insects. It is emphasized that a high degree of purity of the dietary sterols and the climination of the influence of symbionts are essential to present ambiguity in interpreting results. It is pointed out that a sharp distinctio

  7. Resistance to Insecticides in Insects

    OpenAIRE

    ÇAKIR, Şükran; Şengül YAMANEL

    2005-01-01

    In recent years, the frequent usage of insecticides in struggle aganist insects, has caused development of resistance to those chemicals in insects. The increase in dosage of insecticide used due to development of resistance in insects, causes important problems in terms of environment and human health. This study includes topics such as insecticides which are used frequently in insect struggle, insecticide resistant types, genetic changes posing resistance, enzymes of resistance and resistan...

  8. Two conditional tsA mutant simian virus 40 T antigens display marked differences in thermal inactivation.

    OpenAIRE

    Reynisdóttir, I; Prives, C

    1992-01-01

    We have characterized the simian virus 40 (SV40) origin-containing DNA (ori-DNA) replication functions of two SV40 conditional mutant T antigens: tsA438 A-V (tsA58) and tsA357 R-K (tsA30). Both tsA mutant T antigens, immunopurified from recombinant baculovirus-infected insect cells, mediated replication of SV40 ori-DNA in vitro to similar extents as did wild-type T antigen in reactions at 33 degrees C. However, at 41 degrees C, the restrictive temperature, while tsA438 T antigen still generat...

  9. Silencing structural and nonstructural genes in baculovirus by RNA interference.

    Science.gov (United States)

    Flores-Jasso, C Fabian; Valdes, Victor Julian; Sampieri, Alicia; Valadez-Graham, Viviana; Recillas-Targa, Felix; Vaca, Luis

    2004-06-01

    We review several aspects of RNAi and gene silencing with baculovirus. We show that the potency of RNAi in Spodoptera frugiperda (Sf21) insect cells correlates well with the efficiency of transfection of the siRNA. Using a fluorescein-labeled siRNA we found that the siRNA localized in areas surrounding the endoplasmic reticulum (ER). Both long (700 nucleotides long) and small ( approximately 25 nucleotides long) interfering RNAs were equally effective in initiating RNA interference (RNAi), and the duration of the interfering effect was indistinguishable. Even though RNAi in Sf21 cells is very effective, in vitro experiments show that these cells fragment the long dsRNA into siRNA poorly, when compared to HEK cells. Finally, we show that in vivo inhibition of baculovirus infection with dsRNA homologous to genes that are essential for baculovirus infectivity depends strongly on the amount of dsRNA used in the assays. Five hundred nanogram of dsRNA directly injected into the haemolymph of insects prevent animal death to over 95%. In control experiments, over 96% of insects not injected with dsRNA or injected with an irrelevant dsRNA died within a week. These results demonstrate the efficiency of dsRNA for in vivo prevention of a viral infection by virus that is very cytotoxic and lytic in animals.

  10. Stick insects in kindergarten

    OpenAIRE

    Vodeb, Špela

    2014-01-01

    In the graduate thesis, the way of cultivating animals in the kindergarten is presented, the importance of preparation and maintenance of living corner, also the fundamental characteristics of stick insects are listed. In the empirical part, there are results of the questionnaire, which had been answered by 100 kindergarten teachers, mainly about the prevalence of use of living corner in kindergartens; do the teachers choose to use them and why, which animals are most commonly cultivated, and...

  11. [Protection against insects].

    Science.gov (United States)

    Rudin, W

    2005-11-01

    Successful protection against haematophagous insects and ticks, especially in areas where transmission of diseases occurs, requires a consistent application of a combination of appropriate measures. However, this can never substitute a chemoprophylaxis. Which measures have to be used depends on the circumstances under which they have to work. Indoor, physical means such as mosquito-screens on doors and windows, air-conditioners, and bed nets can be used to keep the insects away. These measures can be supplemented or supported by insecticides used as knock-down sprays, by electrical evaporation or for the treatment of screens and bed nets. In the field, if it is not possible to avoid mosquito-areas during phases of activity, appropriate clothing and repellents must provide the protection. Bright, wide pants and shirts of dense weaving covering as much skin as bearable should be preferred. Repellents are sprays, lotions, milks or creams which are evenly applied to the skin to prevent insects from biting. They contain synthetic or natural active substances of substantially varying effectiveness. The gold standard since about 60 years is diethylbenzamine (DEET). There are a few other active substances with a lower risk of side effects, however, combined with a lower effectiveness mainly on people with a high attractiveness for mosquitoes. Products containing an extract of Eucalyptus citriodora provide the best protection amongst those with natural active substances. Wearing bracelets or necklaces treated with repellents, acoustic devices (buzzers), electrocuters, topical or systemic Vitamin B1 or eating garlic are useless measures to prevent insects from biting. PMID:16350532

  12. Undergraduates' mental models about insect anatomy and insect life cycles

    Science.gov (United States)

    Diaz, Arlene Edith

    Educational studies focused on students' alternative conceptions have shown the importance of developing strategies to correct understanding. Identifying and comprehending student mental models are important since they may reflect alternate conceptions about scientific concepts. Mental models have been identified in various science education studies, but little is known about mental models undergraduates hold about insects. This research is significant because it identified mental models undergraduates have about insect anatomy and insect life cycles, exposed students to cognitive conflict by having them complete an online insect tutorial, and analyzed the effectiveness of this insect tutorial in correcting student understanding. An insect assessment was developed and administered pre- and post-instruction to probe students' mental models about insects. Different numbers of undergraduate students participated in different parts of the assessment; 276, 249, 166, and 58 students participated in the listing, drawing. definition, and life cycle parts of the assessment, respectively. The tutorial contained a variety of manipulated insect and non-insect images that challenged the students' understanding and generated cognitive conflict. This intervention guided students in replacing alternate conceptions with correct understanding. It was hypothesized that the tutorial would have a positive impact on student learning about insects. The results suggest that the tutorial had a positive impact on learning.

  13. Molecular evolution of the insect-specific flaviviruses.

    Science.gov (United States)

    Cook, Shelley; Moureau, Gregory; Kitchen, Andrew; Gould, Ernest A; de Lamballerie, Xavier; Holmes, Edward C; Harbach, Ralph E

    2012-02-01

    There has been an explosion in the discovery of 'insect-specific' flaviviruses and/or their related sequences in natural mosquito populations. Herein we review all 'insect-specific' flavivirus sequences currently available and conduct phylogenetic analyses of both the 'insect-specific' flaviviruses and available sequences of the entire genus Flavivirus. We show that there is no statistical support for virus-mosquito co-divergence, suggesting that the 'insect-specific' flaviviruses may have undergone multiple introductions with frequent host switching. We discuss potential implications for the evolution of vectoring within the family Flaviviridae. We also provide preliminary evidence for potential recombination events in the history of cell fusing agent virus. Finally, we consider priorities and guidelines for future research on 'insect-specific' flaviviruses, including the vast potential that exists for the study of biodiversity within a range of potential hosts and vectors, and its effect on the emergence and maintenance of the flaviviruses.

  14. Cleptobiosis in Social Insects

    Directory of Open Access Journals (Sweden)

    Michael D. Breed

    2012-01-01

    Full Text Available In this review of cleptobiosis, we not only focus on social insects, but also consider broader issues and concepts relating to the theft of food among animals. Cleptobiosis occurs when members of a species steal food, or sometimes nesting materials or other items of value, either from members of the same or a different species. This simple definition is not universally used, and there is some terminological confusion among cleptobiosis, cleptoparasitism, brood parasitism, and inquilinism. We first discuss the definitions of these terms and the confusion that arises from varying usage of the words. We consider that cleptobiosis usually is derived evolutionarily from established foraging behaviors. Cleptobionts can succeed by deception or by force, and we review the literature on cleptobiosis by deception or force in social insects. We focus on the best known examples of cleptobiosis, the ectatommine ant Ectatomma ruidum, the harvester ant Messor capitatus, and the stingless bee Lestrimellita limão. Cleptobiosis is facilitated either by deception or physical force, and we discuss both mechanisms. Part of this discussion is an analysis of the ecological implications (competition by interference and the evolutionary effects of cleptobiosis. We conclude with a comment on how cleptobiosis can increase the risk of disease or parasite spread among colonies of social insects.

  15. Eicosanoids: Exploiting Insect Immunity to Improve Biological Control Programs

    Directory of Open Access Journals (Sweden)

    David Stanley

    2012-05-01

    Full Text Available Insects, like all invertebrates, express robust innate, but not adaptive, immune reactions to infection and invasion. Insect immunity is usually resolved into three major components. The integument serves as a physical barrier to infections. Within the hemocoel, the circulating hemocytes are the temporal first line of defense, responsible for clearing the majority of infecting bacterial cells from circulation. Specific cellular defenses include phagocytosis, microaggregation of hemocytes with adhering bacteria, nodulation and encapsulation. Infections also stimulate the humoral component of immunity, which involves the induced expression of genes encoding antimicrobial peptides and activation of prophenoloxidase. These peptides appear in the hemolymph of challenged insects 6–12 hours after the challenge. Prostaglandins and other eicosanoids are crucial mediators of innate immune responses. Eicosanoid biosynthesis is stimulated by infection in insects. Inhibition of eicosanoid biosynthesis lethally renders experimental insects unable to clear bacterial infection from hemolymph. Eicosanoids mediate specific cell actions, including phagocytosis, microaggregation, nodulation, hemocyte migration, hemocyte spreading and the release of prophenoloxidase from oenocytoids. Some invaders have evolved mechanisms to suppress insect immunity; a few of them suppress immunity by targeting the first step in the eicosanoid biosynthesis pathways, the enzyme phospholipase A2. We proposed research designed to cripple insect immunity as a technology to improve biological control of insects. We used dsRNA to silence insect genes encoding phospholipase A2, and thereby inhibited the nodulation reaction to infection. The purpose of this article is to place our view of applying dsRNA technologies into the context of eicosanoid actions in insect immunity. The long-term significance of research in this area lies in developing new pest management

  16. Preparation, characterization and immunogenicity analysis of Chikungunya virus-like particles produced in insect cells%基孔肯雅病毒样颗粒的制备及免疫原性研究

    Institute of Scientific and Technical Information of China (English)

    李建东; 张全福; 张硕; 李川; 刘琴芝; 梁米芳; 李德新

    2015-01-01

    目的 评价基孔肯雅病毒(CHIKV)病毒样颗粒(VLPs)免疫原性.方法 通过构建CHIKV结构蛋白编码基因C-E3-E2-6K-E1昆虫细胞表达载体,然后与杆状病毒线性DNA共转染SF9昆虫细胞制备重组杆状病毒,感染悬浮培养的SF9细胞制备VLPs.IFA、SDS-PAGE和Western-Blot法对表达产物进行鉴定分析,用纯化VLPs免疫BALB/c小鼠,评价免疫原性.结果 CHIKV结构蛋白装配形成病毒样球形颗粒,免疫小鼠可诱导CHIKV特异性抗体,能够有效中和CHIKV感染Vero细胞.结论 CHIKV VLPs能够通过杆状病毒系统在昆虫细胞中有效分泌表达,并具有较强免疫原性,为基于CHIKV VLPs的免疫学检测试剂乃至疫苗的研制奠定了基础.%Objective To prepare the virus-like particles (VLPs) of Chikungunya virus (CHIKV) and evaluate the immunogenicity.Method CHIKV structural protein C-E3-E2-6K-E1 encoding gene were amplified by fusion PCR,and cloned into an insect cell expression vector.The recombinant Baculovirus were recovered by co-transfection of the expression plasmid with baculovirus linear DNA into SF9 insect cells,and CHIKV VLPs were prepared from suspension culture SF9 cells.Structural proteins expression were analyzed using IFA,SDS-PAGE and Western-Blot,and morphological analysis via electron microscopy.Result Which showed that CHIKV structural proteins were secreted into the cell culture supernatant and assembled into virus-like spherical particles.BALB /c mice were immunized with the VLPs,high levels of CHIKV specific antibodies were detected in the sera,and CHIKV infection of Vero cells could be effectively neutralized.Couclusion The results showed that CHIKV VLPs can be efficiently produced by the baculovirus expression system in insect cells,and specific IgG and neutralization antibodies could be induced in mice after VLPs immunization.This research laid the foundation for the development of CHIKV VLPs based on immunological detection reagents and even vaccines.

  17. Edible insects are the future?

    Science.gov (United States)

    van Huis, Arnold

    2016-08-01

    The global increase in demand for meat and the limited land area available prompt the search for alternative protein sources. Also the sustainability of meat production has been questioned. Edible insects as an alternative protein source for human food and animal feed are interesting in terms of low greenhouse gas emissions, high feed conversion efficiency, low land use, and their ability to transform low value organic side streams into high value protein products. More than 2000 insect species are eaten mainly in tropical regions. The role of edible insects in the livelihoods and nutrition of people in tropical countries is discussed, but this food source is threatened. In the Western world, there is an increasing interest in edible insects, and examples are given. Insects as feed, in particular as aquafeed, have a large potential. Edible insects have about the same protein content as conventional meat and more PUFA. They may also have some beneficial health effects. Edible insects need to be processed and turned into palatable dishes. Food safety may be affected by toxicity of insects, contamination with pathogens, spoilage during conservation and allergies. Consumer attitude is a major issue in the Western world and a number of strategies are proposed to encourage insect consumption. We discuss research pathways to make insects a viable sector in food and agriculture: an appropriate disciplinary focus, quantifying its importance, comparing its nutritional value to conventional protein sources, environmental benefits, safeguarding food safety, optimising farming, consumer acceptance and gastronomy.

  18. Edible insects are the future?

    Science.gov (United States)

    van Huis, Arnold

    2016-08-01

    The global increase in demand for meat and the limited land area available prompt the search for alternative protein sources. Also the sustainability of meat production has been questioned. Edible insects as an alternative protein source for human food and animal feed are interesting in terms of low greenhouse gas emissions, high feed conversion efficiency, low land use, and their ability to transform low value organic side streams into high value protein products. More than 2000 insect species are eaten mainly in tropical regions. The role of edible insects in the livelihoods and nutrition of people in tropical countries is discussed, but this food source is threatened. In the Western world, there is an increasing interest in edible insects, and examples are given. Insects as feed, in particular as aquafeed, have a large potential. Edible insects have about the same protein content as conventional meat and more PUFA. They may also have some beneficial health effects. Edible insects need to be processed and turned into palatable dishes. Food safety may be affected by toxicity of insects, contamination with pathogens, spoilage during conservation and allergies. Consumer attitude is a major issue in the Western world and a number of strategies are proposed to encourage insect consumption. We discuss research pathways to make insects a viable sector in food and agriculture: an appropriate disciplinary focus, quantifying its importance, comparing its nutritional value to conventional protein sources, environmental benefits, safeguarding food safety, optimising farming, consumer acceptance and gastronomy. PMID:26908196

  19. Continuous evolution of Bacillus thuringiensis toxins overcomes insect resistance.

    Science.gov (United States)

    Badran, Ahmed H; Guzov, Victor M; Huai, Qing; Kemp, Melissa M; Vishwanath, Prashanth; Kain, Wendy; Nance, Autumn M; Evdokimov, Artem; Moshiri, Farhad; Turner, Keith H; Wang, Ping; Malvar, Thomas; Liu, David R

    2016-05-01

    The Bacillus thuringiensis δ-endotoxins (Bt toxins) are widely used insecticidal proteins in engineered crops that provide agricultural, economic, and environmental benefits. The development of insect resistance to Bt toxins endangers their long-term effectiveness. Here we have developed a phage-assisted continuous evolution selection that rapidly evolves high-affinity protein-protein interactions, and applied this system to evolve variants of the Bt toxin Cry1Ac that bind a cadherin-like receptor from the insect pest Trichoplusia ni (TnCAD) that is not natively bound by wild-type Cry1Ac. The resulting evolved Cry1Ac variants bind TnCAD with high affinity (dissociation constant Kd = 11-41 nM), kill TnCAD-expressing insect cells that are not susceptible to wild-type Cry1Ac, and kill Cry1Ac-resistant T. ni insects up to 335-fold more potently than wild-type Cry1Ac. Our findings establish that the evolution of Bt toxins with novel insect cell receptor affinity can overcome insect Bt toxin resistance and confer lethality approaching that of the wild-type Bt toxin against non-resistant insects. PMID:27120167

  20. Continuous evolution of Bacillus thuringiensis toxins overcomes insect resistance.

    Science.gov (United States)

    Badran, Ahmed H; Guzov, Victor M; Huai, Qing; Kemp, Melissa M; Vishwanath, Prashanth; Kain, Wendy; Nance, Autumn M; Evdokimov, Artem; Moshiri, Farhad; Turner, Keith H; Wang, Ping; Malvar, Thomas; Liu, David R

    2016-05-01

    The Bacillus thuringiensis δ-endotoxins (Bt toxins) are widely used insecticidal proteins in engineered crops that provide agricultural, economic, and environmental benefits. The development of insect resistance to Bt toxins endangers their long-term effectiveness. Here we have developed a phage-assisted continuous evolution selection that rapidly evolves high-affinity protein-protein interactions, and applied this system to evolve variants of the Bt toxin Cry1Ac that bind a cadherin-like receptor from the insect pest Trichoplusia ni (TnCAD) that is not natively bound by wild-type Cry1Ac. The resulting evolved Cry1Ac variants bind TnCAD with high affinity (dissociation constant Kd = 11-41 nM), kill TnCAD-expressing insect cells that are not susceptible to wild-type Cry1Ac, and kill Cry1Ac-resistant T. ni insects up to 335-fold more potently than wild-type Cry1Ac. Our findings establish that the evolution of Bt toxins with novel insect cell receptor affinity can overcome insect Bt toxin resistance and confer lethality approaching that of the wild-type Bt toxin against non-resistant insects.

  1. Plant Defense against Insect Herbivores

    OpenAIRE

    Søren Bak; Joel Fürstenberg-Hägg; Mika Zagrobelny

    2013-01-01

    Plants have been interacting with insects for several hundred million years, leading to complex defense approaches against various insect feeding strategies. Some defenses are constitutive while others are induced, although the insecticidal defense compound or protein classes are often similar. Insect herbivory induce several internal signals from the wounded tissues, including calcium ion fluxes, phosphorylation cascades and systemic- and jasmonate signaling. These are perceived in undamaged...

  2. Insect bite prevention.

    Science.gov (United States)

    Moore, Sarah J; Mordue Luntz, Anne Jennifer; Logan, James G

    2012-09-01

    Protection from the bites of arthropod (insect and acarine) vectors of disease is the first line of defense against disease transmission and should be advised in all cases when traveling abroad. Details are described of the main approaches for the prevention of bites, including topical or skin repellents, impregnated clothing, bed nets, and spatial or aerial repellents and aerosols. The bionomics of the main arthropod vectors of disease are described along with photographic plates and tabulated advice to give the traveler. An in-depth treatment of the different protection methodologies provides an up-to-date overview of the technologies involved. PMID:22963776

  3. The Research of Electroporation Transfect Restructured Baculovirus Genome into Insects Cells%电穿孔转染重组杆状病毒到昆虫细胞的研究

    Institute of Scientific and Technical Information of China (English)

    陈卫东; 杨靖佳; 井申荣; 曾韦锟; 黄芬

    2013-01-01

    目前转染细胞时常用阳离子脂质体如Cellfectin,这种方法成本高,效果不稳定,而用电穿孔转染外源基因到昆虫细胞的文献报道极为少见.构建重组杆状病毒基因组GFP/BAC,用电穿孔法和脂质体法转染到昆虫细胞Sf9中,比较两种方法的转染效率.研究发现,两者转染效率分别为86.14%和86.53%.两种转染方法的子代重组杆状病毒能够继续转染Sf9细胞,荧光强度无明显差异.电穿孔转染效率与脂质体转染接近,但电穿孔法操作简便,周期较短,成本很低.%The basic ion liposome, such as Cellfectin, is usually used to transfect cell at present. The shortage of this method is expensive and instable. While the literature report that transfect exogenous gene into insects cells by electroporation is very rare. Construct the restructured baculovirus genome GFP/BAC and transfect into the insects cells Sf9 by electroporation and liposome Cellfectin, then compare the transfection efficiency of these two methods. The result show that the transfection efficiency of the two methods respectively is 86.14% and 86.53%, and the filial generation restructured baculovirus continue transfect Sf9 cell and the fluorescence intensity of these two methods was not obviously distinct. The transfection efficiency of electroporation is compared with liposome Cellfectin, while the advantages of electroporation is simple operation, short cycle and low cost.

  4. Insect inducible antimicrobial peptides and their applications.

    Science.gov (United States)

    Ezzati-Tabrizi, Reyhaneh; Farrokhi, Naser; Talaei-Hassanloui, Reza; Alavi, Seyed Mehdi; Hosseininaveh, Vahid

    2013-12-01

    Antimicrobial peptides (AMPs) are found as important components of the innate immune system (host defense) of all invertebrates. These peptides can be constitutively expressed or induced in response to microbial infections. Indeed, they vary in their amino acid sequences, potency and antimicrobial activity spectra. The smaller AMPs act greatly by disrupting the structure or function of microbial cell membranes. Here, the insect innate immune system with emphasis on inducible antimicrobial peptide properties against microbial invaders has been discussed.

  5. 1977 Kansas Field Crop Insect Control Recommendations.

    Science.gov (United States)

    Brooks, Leroy; Gates, Dell E.

    This publication is prepared to aid producers in selecting methods of insect population management that have proved effective under Kansas conditions. Topics covered include insect control on alfalfa, soil insects attacking corn, insects attacking above-ground parts of corn, and sorghum, wheat, and soybean insect control. The insecticides…

  6. Insect symbionts as hidden players in insect-plant interactions

    NARCIS (Netherlands)

    Frago, E.; Dicke, M.; Godfray, H.C.J.

    2012-01-01

    There is growing evidence of the importance of microbial mutualistic symbioses in insect-plant interactions. Mutualists may affect host plant range and enable insects to manipulate plant physiology for their own benefit. The plant can also be a route for the horizontal transfer of mutualistic microo

  7. CIRCADIAN GENES AND REGULATION OF DIAPAUSE IN INSECT

    OpenAIRE

    Bajgar, Adam

    2013-01-01

    This thesis considers various roles of circadian clock genes in insect physiology. Application of molecular-biology methods in Pyrrhocoris apterus, non-model insect species, enable us to investigate involvement of circadian clock genes in photoperiod induced physiological responses. We discover involvement of neuroendocrine cells, and a role of Juvenile hormone (JH) signalization in transduction of photoperiodic signalization to peripheral tissues. We found new principles of JH signal diversi...

  8. Eicosanoids: Exploiting Insect Immunity to Improve Biological Control Programs

    OpenAIRE

    David Stanley; Eric Haas; Jon Miller

    2012-01-01

    Insects, like all invertebrates, express robust innate, but not adaptive, immune reactions to infection and invasion. Insect immunity is usually resolved into three major components. The integument serves as a physical barrier to infections. Within the hemocoel, the circulating hemocytes are the temporal first line of defense, responsible for clearing the majority of infecting bacterial cells from circulation. Specific cellular defenses include phagocytosis, microaggregation of hemocytes with...

  9. Could insect phagocytic avoidance by entomogenous fungi have evolved via selection against soil amoeboid predators?

    Science.gov (United States)

    Bidochka, Michael J; Clark, David C; Lewis, Mike W; Keyhani, Nemat O

    2010-07-01

    The entomopathogenic fungi Metarhizium anisopliae and Beauveria bassiana are ubiquitously distributed in soils. As insect pathogens they adhere to the insect cuticle and penetrate through to the insect haemocoel using a variety of cuticle-hydrolysing enzymes. Once in the insect haemocoel they are able to survive and replicate within, and/or evade, phagocytic haemocyte cells circulating in the haemolymph. The mechanism by which these soil fungi acquire virulence factors for insect infection and insect immune avoidance is unknown. We hypothesize that insect phagocytic cell avoidance in M. anisopliae and B. bassiana is the consequence of a survival strategy against soil-inhabiting predatory amoebae. Microscopic examination, phagocytosis assays and amoeba mortality assays showed that these insect pathogenic fungi are phagocytosed by the soil amoeba Acanthamoeba castellanii and can survive and grow within the amoeba, resulting in amoeba death. Mammalian fungal and bacterial pathogens, such as Cryptococcus neoformans and Legionella pneumophila, respectively, show a remarkable overlap between survival against soil amoebae and survival against human macrophages. The insect immune system, particularly phagocytic haemocytes, is analogous to the mammalian macrophage. Our data suggest that the ability of the fungal insect pathogens M. anisopliae and B. bassiana to survive insect phagocytic haemocytes may be a consequence of adaptations that have evolved in order to avoid predation by soil amoebae.

  10. Mosquitoes feeding on insect larvae.

    Science.gov (United States)

    Harris, P; Riordan, D F; Cooke, D

    1969-04-11

    Caged Aedes aegypti and Culex tarsalis are attracted to insect larvae, engorge on their body fluids, and produce viable eggs. Attractiveness of the larvae is related to their size, shape, and color but not to their movement. The possibility that wild mosquitoes substitute insect hemolymph for vertebrate blood is discussed. PMID:5774191

  11. Insect Immunity to Entomopathogenic Fungi.

    Science.gov (United States)

    Lu, H-L; St Leger, R J

    2016-01-01

    The study of infection and immunity in insects has achieved considerable prominence with the appreciation that their host defense mechanisms share many fundamental characteristics with the innate immune system of vertebrates. Studies on the highly tractable model organism Drosophila in particular have led to a detailed understanding of conserved innate immunity networks, such as Toll. However, most of these studies have used opportunistic human pathogens and may not have revealed specialized immune strategies that have arisen through evolutionary arms races with natural insect pathogens. Fungi are the commonest natural insect pathogens, and in this review, we focus on studies using Metarhizium and Beauveria spp. that have addressed immune system function and pathogen virulence via behavioral avoidance, the use of physical barriers, and the activation of local and systemic immune responses. In particular, we highlight studies on the evolutionary genetics of insect immunity and discuss insect-pathogen coevolution. PMID:27131327

  12. Sorghum Insect Problems and Management

    Institute of Scientific and Technical Information of China (English)

    Chunshan Guo; Wei Cui; Xue Feng; Jianzhou Zhao; Guihua Lu

    2011-01-01

    Sorghum (Sorghum bicolor) has high levels of starch, sugar, and fiber and is one of the most important energy crops in the world. Insect damage is one of the challenges that impacts sorghum biomass production. There are at least 150 insect species that can infest sorghum varieties worldwide. These insects can complete several generations within a growing season, they target various parts of sorghum plants at devel- opmental stages, and they cause significant biomass losses. Genetic research has revealed the existence of resistant genetics in sorghum and insect tolerant sorghum varieties have been identified. Various control methods have been developed, yet more effective management is needed for increasing sorghum biomass production. Although there are no transgenic sorghum products on the market yet, biotechnology has been recognized as an important tool for controlling insect pests and increasing sorghum production.

  13. Flying insects and Campylobacter

    DEFF Research Database (Denmark)

    Hald, Birthe; Sommer, Helle Mølgaard; Skovgård, Henrik

    Campylobacter in flies Flies of the Muscidae family forage on all kind of faeces – various fly species have different preferences. M domestica prefer pigs, horses and cattle faeces, animals which are all known to frequently excrete Campylobacter. As a result, the insects pick up pathogenic micro...... organisms, which may collect on their bodies or survive passage through the fly gut. Campylobacter and other pathogens are then easily transferred to other surfaces, for instance peoples food – or to broiler houses where they may be swallowed by chickens or contaminate the environment. On a large material...... of several species of flies collected outside broiler houses, merely ~1% of the flies were found Campylobacter positive. However, the prevalence varied considerably with fly species, time of the year, and availability of Campylobacter sources. Influx of flies to broiler houses As the influx of flies...

  14. Plant defense against insect herbivores

    DEFF Research Database (Denmark)

    Fürstenberg-Hägg, Joel; Zagrobelny, Mika; Bak, Søren

    2013-01-01

    , defense compounds. These bioactive specialized plant defense compounds may repel or intoxicate insects, while defense proteins often interfere with their digestion. Volatiles are released upon herbivory to repel herbivores, attract predators or for communication between leaves or plants, and to induce...... defense responses. Plants also apply morphological features like waxes, trichomes and latices to make the feeding more difficult for the insects. Extrafloral nectar, food bodies and nesting or refuge sites are produced to accommodate and feed the predators of the herbivores. Meanwhile, herbivorous insects...

  15. Insect symbionts in food webs.

    Science.gov (United States)

    McLean, Ailsa H C; Parker, Benjamin J; Hrček, Jan; Henry, Lee M; Godfray, H Charles J

    2016-09-01

    Recent research has shown that the bacterial endosymbionts of insects are abundant and diverse, and that they have numerous different effects on their hosts' biology. Here we explore how insect endosymbionts might affect the structure and dynamics of insect communities. Using the obligate and facultative symbionts of aphids as an example, we find that there are multiple ways that symbiont presence might affect food web structure. Many symbionts are now known to help their hosts escape or resist natural enemy attack, and others can allow their hosts to withstand abiotic stress or affect host plant use. In addition to the direct effect of symbionts on aphid phenotypes there may be indirect effects mediated through trophic and non-trophic community interactions. We believe that by using data from barcoding studies to identify bacterial symbionts, this extra, microbial dimension to insect food webs can be better elucidated.This article is part of the themed issue 'From DNA barcodes to biomes'. PMID:27481779

  16. Radar Observation of Insects - Mosquitoes

    Science.gov (United States)

    Frost, E.; Downing, J.

    1979-01-01

    Tests were conducted at several sites over the coastal lowlands of New Jersey and over a region of high plains and low mountains in Oklahoma. In one area, a salt marsh in New Jersey, extensive ground tests were combined with laboratory data on expected insect backscatter to arrive at an extremely convincing model of the insect origin of most Dot Angels. A great deal of insight was studied from radar on the buildup and dispersal of insect swarms, since radar can follow where other means of trapping and observation cannot. Data on large-scale behavior as a function of wind and topography are presented. Displayed techniques which show individual or small swarm motion within some larger cloud or mass, or which can show the overall motion over great distances were developed. The influence of wind and terrain on insect motion and dispersal is determined from radar data.

  17. Learning and cognition in insects.

    Science.gov (United States)

    Giurfa, Martin

    2015-01-01

    Insects possess small brains but exhibit sophisticated behavioral performances. Recent works have reported the existence of unsuspected cognitive capabilities in various insect species, which go beyond the traditional studied framework of simple associative learning. In this study, I focus on capabilities such as attention, social learning, individual recognition, concept learning, and metacognition, and discuss their presence and mechanistic bases in insects. I analyze whether these behaviors can be explained on the basis of elemental associative learning or, on the contrary, require higher-order explanations. In doing this, I highlight experimental challenges and suggest future directions for investigating the neurobiology of higher-order learning in insects, with the goal of uncovering l architectures underlying cognitive processing.

  18. Insect symbionts in food webs

    Science.gov (United States)

    Henry, Lee M.

    2016-01-01

    Recent research has shown that the bacterial endosymbionts of insects are abundant and diverse, and that they have numerous different effects on their hosts' biology. Here we explore how insect endosymbionts might affect the structure and dynamics of insect communities. Using the obligate and facultative symbionts of aphids as an example, we find that there are multiple ways that symbiont presence might affect food web structure. Many symbionts are now known to help their hosts escape or resist natural enemy attack, and others can allow their hosts to withstand abiotic stress or affect host plant use. In addition to the direct effect of symbionts on aphid phenotypes there may be indirect effects mediated through trophic and non-trophic community interactions. We believe that by using data from barcoding studies to identify bacterial symbionts, this extra, microbial dimension to insect food webs can be better elucidated. This article is part of the themed issue ‘From DNA barcodes to biomes’. PMID:27481779

  19. Clinical Application of Insect Drugs

    Institute of Scientific and Technical Information of China (English)

    钟洪; 赵洁

    2003-01-01

    @@ Chinese insect drugs are drastic in nature, capable ofclearing channels and collaterals to promote a freeflow of qi and blood, and effective in someintractable and obstinate diseases due to long-termstagnation of phlegm and blood, which are hard to betreated by ordinary Chinese drugs. In clinic, properuse of insect drugs can often help raise thetherapeutic effects. Some commonly used pairs ofinsect drugs are introduced in the following.

  20. Encapsulation and nodulation in insects

    OpenAIRE

    Dubovskiy IM; Kryukova NA; Glupov VV; Ratcliffe NA

    2016-01-01

    Evolution of the insect immune system led to the creation of a comprehensive cellular defense system, not only involving phagocytosis, but also encapsulation and nodulation (both often referred to as capsule formation) allowing the isolation and neutralization of invading pathogens and parasites. Such reactions are closely related to the anatomical and physiological characteristics in insects with their external skeleton and open circulatory blood system. Encapsulation and nodulat...

  1. How Do Insects Help the Environment?

    Science.gov (United States)

    Hevel, Gary

    2005-01-01

    There are some 5 to 30 million insect species estimated in the world--and the majority of these have yet to be collected or named by science! Of course, the most well known insects are those that cause disease or compete for human agricultural products, but these insects represent only a small fraction of the world's insect population. In reality,…

  2. Evolutionary conservation and changes in insect TRP channels

    Directory of Open Access Journals (Sweden)

    Tominaga Makoto

    2009-09-01

    Full Text Available Abstract Background TRP (Transient Receptor Potential channels respond to diverse stimuli and thus function as the primary integrators of varied sensory information. They are also activated by various compounds and secondary messengers to mediate cell-cell interactions as well as to detect changes in the local environment. Their physiological roles have been primarily characterized only in mice and fruit flies, and evolutionary studies are limited. To understand the evolution of insect TRP channels and the mechanisms of integrating sensory inputs in insects, we have identified and compared TRP channel genes in Drosophila melanogaster, Bombyx mori, Tribolium castaneum, Apis mellifera, Nasonia vitripennis, and Pediculus humanus genomes as part of genome sequencing efforts. Results All the insects examined have 2 TRPV, 1 TRPN, 1 TRPM, 3 TRPC, and 1 TRPML subfamily members, demonstrating that these channels have the ancient origins in insects. The common pattern also suggests that the mechanisms for detecting mechanical and visual stimuli and maintaining lysosomal functions may be evolutionarily well conserved in insects. However, a TRPP channel, the most ancient TRP channel, is missing in B. mori, A. mellifera, and N. vitripennis. Although P. humanus and D. melanogaster contain 4 TRPA subfamily members, the other insects have 5 TRPA subfamily members. T. castaneum, A. mellifera, and N. vitripennis contain TRPA5 channels, which have been specifically retained or gained in Coleoptera and Hymenoptera. Furthermore, TRPA1, which functions for thermotaxis in Drosophila, is missing in A. mellifera and N. vitripennis; however, they have other Hymenoptera-specific TRPA channels (AmHsTRPA and NvHsTRPA. NvHsTRPA expressed in HEK293 cells is activated by temperature increase, demonstrating that HsTRPAs function as novel thermal sensors in Hymenoptera. Conclusion The total number of insect TRP family members is 13-14, approximately half that of mammalian TRP

  3. Modeling resistance to genetic control of insects

    OpenAIRE

    Alphey, Nina; Bonsall, Michael B.; Alphey, Luke

    2011-01-01

    Abstract The sterile insect technique is an area-wide pest control method that reduces pest populations by releasing mass-reared sterile insects which compete for mates with wild insects. Modern molecular tools have created possibilities for improving and extending the sterile insect technique. As with any new insect control method, questions arise about potential resistance. Genetic RIDL?RIDL? is a registered trademark of Oxitec Limited, UKRIDL? is a registered trademark of Oxitec...

  4. Herbivory increases diversification across insect clades

    OpenAIRE

    John J Wiens; Lapoint, Richard T.; Whiteman, Noah K.

    2015-01-01

    Insects contain more than half of all living species, but the causes of their remarkable diversity remain poorly understood. Many authors have suggested that herbivory has accelerated diversification in many insect clades. However, others have questioned the role of herbivory in insect diversification. Here, we test the relationships between herbivory and insect diversification across multiple scales. We find a strong, positive relationship between herbivory and diversification among insect o...

  5. Induction of Intracellular Ca2+ and pH Changes in Sf9 Insect Cells by Rhodojaponin-III, A Natural Botanic Insecticide Isolated from Rhododendron molle

    Directory of Open Access Journals (Sweden)

    Yan-Bo Zhang

    2011-04-01

    Full Text Available Many studies on intracellular calcium ([Ca2+]i and intracellular pH (pHi have been carried out due to their importance in regulation of different cellular functions. However, most of the previous studies are focused on human or mammalian cells. The purpose of the present study was to characterize the effect of Rhodojaponin-III (R-III on [Ca2+]i and pHi and the proliferation of Sf9 cells. R-III strongly inhibited Sf9 cells proliferation with a time- and dose-dependent manner. Flow cytometry established that R-III interfered with Sf9 cells division and arrested them in G2/M. By using confocal scanning technique, effects of R-III on intracellular free calcium ([Ca2+]i and intracellular pH (pHi in Sf9 cells were determined. R-III induced a significant dose-dependent (1, 10, 100, 200 μg/mL increase in [Ca2+]i and pHi of Sf9 cells in presence of Ca2+-containing solution (Hanks and an irreversible decrease in the absence of extra cellular Ca2+. We also found that both extra cellular Ca2+ and intracellular Ca2+ stores contributed to the increase of [Ca2+]i, because completely treating Sf9 cells with CdCl2 (5 mM, a Ca2+ channels blocker, R-III (100 μg/mL induced a transient elevation of [Ca2+]i in case of cells either in presence of Ca2+ containing or Ca2+ free solution. In these conditions, pHi showed similar changes with that of [Ca2+]i on the whole. Accordingly, we supposed that there was a certain linkage for change of [Ca2+]i, cell cycle arrest, proliferation inhibition in Sf9 cells induced by R-III.

  6. Can insects develop resistance to insect pathogenic fungi?

    Directory of Open Access Journals (Sweden)

    Ivan M Dubovskiy

    Full Text Available Microevolutionary adaptations and mechanisms of fungal pathogen resistance were explored in a melanic population of the Greater wax moth, Galleria mellonella. Under constant selective pressure from the insect pathogenic fungus Beauveria bassiana, 25(th generation larvae exhibited significantly enhanced resistance, which was specific to this pathogen and not to another insect pathogenic fungus, Metarhizium anisopliae. Defense and stress management strategies of selected (resistant and non-selected (susceptible insect lines were compared to uncover mechanisms underpinning resistance, and the possible cost of those survival strategies. We hypothesize that the insects developed a transgenerationally primed resistance to the fungus B. bassiana, a costly trait that was achieved not by compromising life-history traits but rather by prioritizing and re-allocating pathogen-species-specific augmentations to integumental front-line defenses that are most likely to be encountered by invading fungi. Specifically during B. bassiana infection, systemic immune defenses are suppressed in favour of a more limited but targeted repertoire of enhanced responses in the cuticle and epidermis of the integument (e.g. expression of the fungal enzyme inhibitor IMPI, and cuticular phenoloxidase activity. A range of putative stress-management factors (e.g. antioxidants is also activated during the specific response of selected insects to B. bassiana but not M. anisopliae. This too occurs primarily in the integument, and probably contributes to antifungal defense and/or helps ameliorate the damage inflicted by the fungus or the host's own immune responses.

  7. Insect peptide CopA3-induced protein degradation of p27Kip1 stimulates proliferation and protects neuronal cells from apoptosis

    Energy Technology Data Exchange (ETDEWEB)

    Nam, Seung Taek; Kim, Dae Hong; Lee, Min Bum; Nam, Hyo Jung; Kang, Jin Ku; Park, Mi Jung; Lee, Ik Hwan [Department of Life Science, College of Natural Science, Daejin University, Pocheon, Gyeonggido 487-711 (Korea, Republic of); Seok, Heon [Department of Biomedical Science, Jungwon University, Goesan, Chungcheongbukdo 367-700 (Korea, Republic of); Lee, Dong Gun [School of Life Sciences and Biotechnology, College of Natural Sciences, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Hwang, Jae Sam [Department of Agricultural Biology, National Academy of Agricultural Science, RDA, Suwon 441-707 (Korea, Republic of); Kim, Ho, E-mail: hokim@daejin.ac.kr [Department of Life Science, College of Natural Science, Daejin University, Pocheon, Gyeonggido 487-711 (Korea, Republic of)

    2013-07-19

    Highlights: •CopA3 peptide isolated from the Korean dung beetle has antimicrobial activity. •Our study reported that CopA3 has anticancer and immunosuppressive effects. •We here demonstrated that CopA3 has neurotropic and neuroprotective effects. •CopA3 degrades p27Kip1 protein and this mediates effects of CopA3 on neuronal cells. -- Abstract: We recently demonstrated that the antibacterial peptide, CopA3 (a D-type disulfide dimer peptide, LLCIALRKK), inhibits LPS-induced macrophage activation and also has anticancer activity in leukemia cells. Here, we examined whether CopA3 could affect neuronal cell proliferation. We found that CopA3 time-dependently increased cell proliferation by up to 31 ± 2% in human neuroblastoma SH-SY5Y cells, and up to 29 ± 2% in neural stem cells isolated from neonatal mouse brains. In both cell types, CopA3 also significantly inhibited the apoptosis and viability losses caused by 6-hydroxy dopamine (a Parkinson disease-mimicking agent) and okadaic acid (an Alzheimer’s disease-mimicking agent). Immunoblotting revealed that the p27Kip1 protein (a negative regulator of cell cycle progression) was markedly degraded in CopA3-treated SH-SY5Y cells. Conversely, an adenovirus expressing p27Kip1 significantly inhibited the antiapoptotic effects of CopA3 against 6-hydroxy dopamine- and okadaic acid-induced apoptosis, and decreased the neurotropic effects of CopA3. These results collectively suggest that CopA3-mediated protein degradation of p27Kip1 may be the main mechanism through which CopA3 exerts neuroprotective and neurotropic effects.

  8. Radiations: tool for insect pest management

    International Nuclear Information System (INIS)

    The discovery that X-rays or gamma radiation could cause sufficient genetic damage to insect reproductive systems to induce sterility resulted from work conducted by H.J. Muller starting in the 1920s. The sterilizing effect of radiation was noted by scientists of the US Department of Agriculture who had been seeking a method to sterilize insects for many years. These scientists had theorized that if large numbers of the target insect species were reared, sterilized, and released into the field, the sterile insects would mate with the wild insects. These mating would result in no offspring and thus a decline in the population would be obtained. They calculated that if sufficient numbers of sterile insects were released, reproductive rate for the wild population would rapidly decline and reach zero. In simple language, birth control of insects. Radiation sterilization was the answer. In a SIT operation, radiation is used to sexually sterilize insects. Since the SIT is species specific, the selection the insect pest or group of pests on which to work is of primary importance. The Joint Division of the IAEA Food and Agriculture Organization (FAO) has been involved in the use of isotopes and radiation in insect control since 1964. Isotopes are used as tags or markers, for instance, of chemical molecules, insects, or plants. For example, with these tags one can follow the fate of insecticides within insects and the environment; the incorporation of nutrients into the insect; and the movements of insects under field conditions. They also can plants on which insects feed so that the quantity of consumed food can be measured and directly correlated with plant resistance. They can be used as well to follow parasites and predators of insects - for example, their movements, numbers, and ability to help control insect pests. Radiations therefore have come as a novel tool to combat insect pest problem and in future could be very helpful in various other ways, of be it be cost

  9. Insects, infestations and nutrient fluxes

    Science.gov (United States)

    Michalzik, B.

    2012-04-01

    Forest ecosystems are characterized by a high temporal and spatial variability in the vertical transfer of energy and matter within the canopy and the soil compartment. The mechanisms and controlling factors behind canopy processes and system-internal transfer dynamics are imperfectly understood at the moment. Seasonal flux diversities and inhomogeneities in throughfall composition have been reported from coniferous and deciduous forests, and in most cases leaf leaching has been considered as principle driver for differences in the amount and quality of nutrients and organic compounds (Tukey and Morgan 1963). Since herbivorous insects and the processes they initiate received less attention in past times, ecologists now emphasize the need for linking biological processes occurring in different ecosystem strata to explain rates and variability of nutrient cycling (Bardgett et al. 1998, Wardle et al. 2004). Consequently, herbivore insects in the canopies of forests are increasingly identified to play an important role for the (re)cycling and availability of nutrients, or, more generally, for the functioning of ecosystems not only in outbreak situations but also at endemic (non-outbreak) density levels (Stadler et al. 2001, Hunter et al. 2003). Before, little attention was paid to insect herbivores when quantifying element and energy fluxes through ecosystems, although the numerous and different functions insects fulfill in ecosystems (e.g. as pollinators, herbivores or detritivores) were unanimously recognized (Schowalter 2000). Amongst the reasons for this restraint was the argument that the total biomass of insects tends to be relatively low compared to the biomass of trees or the pool of soil organic matter (Ohmart et al. 1983). A second argument which was put forward to justify the inferior role of insects in nutrient cycling were the supposed low defoliation losses between 5-10% of the annual leaf biomass, or net primary production, due to insect herbivory under

  10. Production of biologically active recombinant bovine interferon-gamma by two different baculovirus gene expression systems using insect cells and silkworm larvae.

    Science.gov (United States)

    Murakami, K; Uchiyama, A; Kokuho, T; Mori, Y; Sentsui, H; Yada, T; Tanigawa, M; Kuwano, A; Nagaya, H; Ishiyama, S; Kaki, H; Yokomizo, Y; Inumaru, S

    2001-01-01

    The full-length bovine interferon-gamma (bIFN-gamma) cDNA, including the secretion signal peptide coding region was recloned into baculovirus transfer vectors pAcYM1 and pBm050. These vectors were co-transfected with Autographa californica nuclear polyhedrosis virus (AcNPV) or Bombyx mori nuclear polyhedrosis virus (BmNPV) DNA into Spodoptera frugiperda cells (SF21AE) and Bombyx mori cells (BmN), respectively. The recombinant viruses, named AcBIFN-gamma and BmBIFN-gamma, were then recovered. Recombinant bIFN-gamma (rbIFN-gamma) was accumulated in the culture fluid of AcBIFN-gamma-infected Trichoplusia ni cells and BmBIFN-gamma-infected silkworm larvae. These rbIFN-gamma forms were shown to be glycosylated 20 and 22 kDa proteins as confirmed by SDS-PAGE and tunicamycin treatment. These products were sensitive to cystein proteinase. Both rbIFN-gamma proteins, showed high-level biological activities by plaque reduction assay using vesicular stomatitis virus, and MHC class II antigen induction on bovine macrophage cells. PMID:11145838

  11. NIR detects, destroys insect pests

    International Nuclear Information System (INIS)

    What’s good for Georgia peanuts may also be good for Kansas wheat. An electric eye that scans all food-grade peanuts for visual defects could one day do the same for wheat kernels. For peanuts, it’s a proven method for monitoring quality. In wheat, scanning with near-infrared (NIR) energy can reveal hidden insect infestations that lower wheat quality. ARS entomologists James E. Throne and James E. Baker and ARS agricultural engineer Floyd E. Dowell are the first to combine NIR with an automated grain-handling system to rapidly detect insects hidden in single wheat kernels

  12. Spectral organization of ommatidia in flower-visiting insects

    NARCIS (Netherlands)

    Wakakuwa, Motohiro; Stavenga, Doekele G.; Arikawa, Kentaro

    2007-01-01

    This article reviews recent advances of studies on the spectral organization of the compound eye in lepidopteran and hymenopteran insects. The compound eyes consist of ommatidia, which contain a set of photoreceptor cells. The common feature is that the ommatidia can be divided into three types, acc

  13. The biosynthetic products of chinese insect medicine, Aspongopus chinensis

    Science.gov (United States)

    Luo, Xiao-Hong; Wang, Xiao-Zheng; Jiang, Hai-Long; Yang, Jun-Li; Crews, Phillip; Valeriote, Frederick A.; Wu, Quan-Xiang

    2012-01-01

    A new oxazole (1) was obtained from chinese insect medicine Aspongopus chinensis, along with three known N-acetyldopamine derivatives (2–4). Their structures were determined on the basis of NMR and ESI-MS analyses. The possible biosynthetic pathways of the isolated compounds are discussed. Cytotoxicities of those compounds against 10 selected cancer cells were measured in vitro. PMID:22430116

  14. Codon bias and gene ontology in holometabolous and hemimetabolous insects.

    Science.gov (United States)

    Carlini, David B; Makowski, Matthew

    2015-12-01

    The relationship between preferred codon use (PCU), developmental mode, and gene ontology (GO) was investigated in a sample of nine insect species with sequenced genomes. These species were selected to represent two distinct modes of insect development, holometabolism and hemimetabolism, with an aim toward determining whether the differences in developmental timing concomitant with developmental mode would be mirrored by differences in PCU in their developmental genes. We hypothesized that the developmental genes of holometabolous insects should be under greater selective pressure for efficient translation, manifest as increased PCU, than those of hemimetabolous insects because holometabolism requires abundant protein expression over shorter time intervals than hemimetabolism, where proteins are required more uniformly in time. Preferred codon sets were defined for each species, from which the frequency of PCU for each gene was obtained. Although there were substantial differences in the genomic base composition of holometabolous and hemimetabolous insects, both groups exhibited a general preference for GC-ending codons, with the former group having higher PCU averaged across all genes. For each species, the biological process GO term for each gene was assigned that of its Drosophila homolog(s), and PCU was calculated for each GO term category. The top two GO term categories for PCU enrichment in the holometabolous insects were anatomical structure development and cell differentiation. The increased PCU in the developmental genes of holometabolous insects may reflect a general strategy to maximize the protein production of genes expressed in bursts over short time periods, e.g., heat shock proteins. J. Exp. Zool. (Mol. Dev. Evol.) 324B: 686-698, 2015. © 2015 Wiley Periodicals, Inc. PMID:26498580

  15. Insects as a Nitrogen Source for Plants.

    Science.gov (United States)

    Behie, Scott W; Bidochka, Michael J

    2013-01-01

    Many plants have evolved adaptations in order to survive in low nitrogen environments. One of the best-known adaptations is that of plant symbiosis with nitrogen-fixing bacteria; this is the major route by which nitrogen is incorporated into plant biomass. A portion of this plant-associated nitrogen is then lost to insects through herbivory, and insects represent a nitrogen reservoir that is generally overlooked in nitrogen cycles. In this review we show three specialized plant adaptations that allow for the recovery of insect nitrogen; that is, plants gaining nitrogen from insects. First, we show specialized adaptations by carnivorous plants in low nitrogen habitats. Insect carnivorous plants such as pitcher plants and sundews (Nepenthaceae/Sarraceniaceae and Drosera respectively) are able to obtain substantial amounts of nitrogen from the insects that they capture. Secondly, numerous plants form associations with mycorrhizal fungi that can provide soluble nitrogen from the soil, some of which may be insect-derived nitrogen, obtained from decaying insects or insect frass. Finally, a specialized group of endophytic, insect-pathogenic fungi (EIPF) provide host plants with insect-derived nitrogen. These soil-inhabiting fungi form a remarkable symbiosis with certain plant species. They can infect a wide range of insect hosts and also form endophytic associations in which they transfer insect-derived nitrogen to the plant. Root colonizing fungi are found in disparate fungal phylogenetic lineages, indicating possible convergent evolutionary strategies between taxa, evolution potentially driven by access to carbon-containing root exudates. PMID:26462427

  16. Insects as a Nitrogen Source for Plants

    Directory of Open Access Journals (Sweden)

    Michael J. Bidochka

    2013-07-01

    Full Text Available Many plants have evolved adaptations in order to survive in low nitrogen environments. One of the best-known adaptations is that of plant symbiosis with nitrogen-fixing bacteria; this is the major route by which nitrogen is incorporated into plant biomass. A portion of this plant-associated nitrogen is then lost to insects through herbivory, and insects represent a nitrogen reservoir that is generally overlooked in nitrogen cycles. In this review we show three specialized plant adaptations that allow for the recovery of insect nitrogen; that is, plants gaining nitrogen from insects. First, we show specialized adaptations by carnivorous plants in low nitrogen habitats. Insect carnivorous plants such as pitcher plants and sundews (Nepenthaceae/Sarraceniaceae and Drosera respectively are able to obtain substantial amounts of nitrogen from the insects that they capture. Secondly, numerous plants form associations with mycorrhizal fungi that can provide soluble nitrogen from the soil, some of which may be insect-derived nitrogen, obtained from decaying insects or insect frass. Finally, a specialized group of endophytic, insect-pathogenic fungi (EIPF provide host plants with insect-derived nitrogen. These soil-inhabiting fungi form a remarkable symbiosis with certain plant species. They can infect a wide range of insect hosts and also form endophytic associations in which they transfer insect-derived nitrogen to the plant. Root colonizing fungi are found in disparate fungal phylogenetic lineages, indicating possible convergent evolutionary strategies between taxa, evolution potentially driven by access to carbon-containing root exudates.

  17. Expression of biologically active recombinant equine interferon-gamma by two different baculovirus gene expression systems using insect cells and silkworm larvae.

    Science.gov (United States)

    Wu, Donglai; Murakami, Kenji; Liu, Nihong; Inoshima, Yasuo; Yokoyama, Takashi; Kokuho, Takehiro; Inumaru, Shigeki; Matsumura, Tomio; Kondo, Takashi; Nakano, Katsushige; Sentsui, Hiroshi

    2002-10-21

    The full-length equine interferon-gamma (eIFN-gamma) cDNA, including the secretion signal peptide coding region, was recloned into baculovirus transfer vector pAcYM1. This vector was co-transfected with Autographa californica nuclear polyhedrosis virus DNA or hybrid nuclear polyhedrosis virus DNA into Spodoptera frugiperda cells. The recombinant viruses, named AcEIFN-gamma and HyEIFN-gamma, were then recovered. Recombinant eIFN-gamma (reIFN-gamma) was accumulated in the culture fluid of the AcEIFN-gamma or HyEIFN-gamma infected Tricoplusia ni -derived cell line, BTI TN 5B1-4, and hemolymph of HyEIFN-gamma infected silkworm larvae. These reIFN-gamma forms were shown to be 14, 16, 18 and 20kDa proteins, and glycosylated as confirmed by SDS-PAGE and tunicamycin treatment. Both reIFN-gamma proteins, showed high-level biological activities to vesicular stomatitis virus by cytopathic effect reduction assay, and MHC class II antigen induction on the equine fetal kidney-78 cell line. PMID:12445800

  18. Using Pitfall Traps to Monitor Insect Activity

    OpenAIRE

    Laub, Curtis A., 1955-; Youngman, R. R. (Roger Ray); Love, Kenner; Mize, Timothy

    2009-01-01

    Discusses the use of pitfall traps to monitor insect populations. Describes how to install the traps, and how to process and store insect specimens. Notes some concerns about killing and preserving agents used in the pitfall traps.

  19. FAQ: Insect Repellent Use and Safety

    Science.gov (United States)

    ... Surveillance Software Health Education Public Service Videos Insect Repellent Use & Safety Recommend on Facebook Tweet Share Compartir ... insect repellent products? What is permethrin? Which mosquito repellents work best? CDC recommends the use of products ...

  20. The Curious Connection Between Insects and Dreams

    Directory of Open Access Journals (Sweden)

    Barrett A. Klein

    2011-12-01

    Full Text Available A majority of humans spend their waking hours surrounded by insects, so it should be no surprise that insects also appear in humans’ dreams as we sleep. Dreaming about insects has a peculiar history, marked by our desire to explain a dream’s significance and by the tactic of evoking emotions by injecting insects in dream-related works of art, film, music, and literature. I surveyed a scattered literature for examples of insects in dreams, first from the practices of dream interpretation, psychiatry, and scientific study, then from fictional writings and popular culture, and finally in the etymology of entomology by highlighting insects with dream-inspired Latinate names. A wealth of insects in dreams, as documented clinically and culturally, attests to the perceived relevance of dreams and to the ubiquity of insects in our lives.

  1. The Curious Connection Between Insects and Dreams.

    Science.gov (United States)

    Klein, Barrett A

    2011-01-01

    A majority of humans spend their waking hours surrounded by insects, so it should be no surprise that insects also appear in humans' dreams as we sleep. Dreaming about insects has a peculiar history, marked by our desire to explain a dream's significance and by the tactic of evoking emotions by injecting insects in dream-related works of art, film, music, and literature. I surveyed a scattered literature for examples of insects in dreams, first from the practices of dream interpretation, psychiatry, and scientific study, then from fictional writings and popular culture, and finally in the etymology of entomology by highlighting insects with dream-inspired Latinate names. A wealth of insects in dreams, as documented clinically and culturally, attests to the perceived relevance of dreams and to the ubiquity of insects in our lives. PMID:26467945

  2. 7 CFR 51.2122 - Insect injury.

    Science.gov (United States)

    2010-01-01

    ... Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE REGULATIONS AND STANDARDS UNDER THE AGRICULTURAL MARKETING ACT OF 1946... insect, web, or frass is present or there is definite evidence of insect feeding....

  3. Edible insects are the future?

    NARCIS (Netherlands)

    Huis, van Arnold

    2016-01-01

    The global increase in demand for meat and the limited land area available prompt the search for alternative protein sources. Also the sustainability of meat production has been questioned. Edible insects as an alternative protein source for human food and animal feed are interesting in terms of

  4. Insects Affecting Man. MP-21.

    Science.gov (United States)

    Lawson, Fred A.; Spackman, Everett

    The insects discussed in this document are those which have a direct effect upon humans either through a permanent association, as with lice, or a temporary association in the case of flies, bees, wasps, and spiders. In each case, life cycles and identifying characteristics are presented with remarks about the specific effect incurred by man. (CS)

  5. Making Connections with Insect Royalty.

    Science.gov (United States)

    Hobbie, Ann

    2000-01-01

    Describes a one-month sixth grade class activity with monarch butterflies called Monarch in the Classroom. Students learn about insects, especially the class material butterflies, including their life cycle, eating habits, migration, and how they overwinter. The lesson plan covers sorting animals, focusing on features, analyzing the community for…

  6. Enhanced methanol production in plants provides broad spectrum insect resistance.

    Directory of Open Access Journals (Sweden)

    Sameer Dixit

    Full Text Available Plants naturally emit methanol as volatile organic compound. Methanol is toxic to insect pests; but the quantity produced by most of the plants is not enough to protect them against invading insect pests. In the present study, we demonstrated that the over-expression of pectin methylesterase, derived from Arabidopsis thaliana and Aspergillus niger, in transgenic tobacco plants enhances methanol production and resistance to polyphagous insect pests. Methanol content in the leaves of transgenic plants was measured using proton nuclear spectroscopy (1H NMR and spectra showed up to 16 fold higher methanol as compared to control wild type (WT plants. A maximum of 100 and 85% mortality in chewing insects Helicoverpa armigera and Spodoptera litura larvae was observed, respectively when fed on transgenic plants leaves. The surviving larvae showed less feeding, severe growth retardation and could not develop into pupae. In-planta bioassay on transgenic lines showed up to 99 and 75% reduction in the population multiplication of plant sap sucking pests Myzus persicae (aphid and Bemisia tabaci (whitefly, respectively. Most of the phenotypic characters of transgenic plants were similar to WT plants. Confocal microscopy showed no deformities in cellular integrity, structure and density of stomata and trichomes of transgenic plants compared to WT. Pollen germination and tube formation was also not affected in transgenic plants. Cell wall enzyme transcript levels were comparable with WT. This study demonstrated for the first time that methanol emission can be utilized for imparting broad range insect resistance in plants.

  7. High plasticity in epithelial morphogenesis during insect dorsal closure

    Directory of Open Access Journals (Sweden)

    Kristen A. Panfilio

    2013-09-01

    Insect embryos complete the outer form of the body via dorsal closure (DC of the epidermal flanks, replacing the transient extraembryonic (EE tissue. Cell shape changes and morphogenetic behavior are well characterized for DC in Drosophila, but these data represent a single species with a secondarily reduced EE component (the amnioserosa that is not representative across the insects. Here, we examine DC in the red flour beetle, Tribolium castaneum, providing the first detailed, functional analysis of DC in an insect with complete EE tissues (distinct amnion and serosa. Surprisingly, we find that differences between Drosophila and Tribolium DC are not restricted to the EE tissue, but also encompass the dorsal epidermis, which differs in cellular architecture and method of final closure (zippering. We then experimentally manipulated EE tissue complement via RNAi for Tc-zen1, allowing us to eliminate the serosa and still examine viable DC in a system with a single EE tissue (the amnion. We find that the EE domain is particularly plastic in morphogenetic behavior and tissue structure. In contrast, embryonic features and overall kinetics are robust to Tc-zen1RNAi manipulation in Tribolium and conserved with a more distantly related insect, but remain substantially different from Drosophila. Although correct DC is essential, plasticity and regulative, compensatory capacity have permitted DC to evolve within the insects. Thus, DC does not represent a strong developmental constraint on the nature of EE development, a property that may have contributed to the reduction of the EE component in the fly lineage.

  8. In vivo subcellular localization of Mal de Rio Cuarto virus (MRCV) non-structural proteins in insect cells reveals their putative functions

    Energy Technology Data Exchange (ETDEWEB)

    Maroniche, Guillermo A.; Mongelli, Vanesa C.; Llauger, Gabriela; Alfonso, Victoria; Taboga, Oscar [Instituto de Biotecnologia, CICVyA, Instituto Nacional de Tecnologia Agropecuaria (IB-INTA), Las cabanas y Los Reseros s/n. Hurlingham Cp 1686, Buenos Aires (Argentina); Vas, Mariana del, E-mail: mdelvas@cnia.inta.gov.ar [Instituto de Biotecnologia, CICVyA, Instituto Nacional de Tecnologia Agropecuaria (IB-INTA), Las cabanas y Los Reseros s/n. Hurlingham Cp 1686, Buenos Aires (Argentina)

    2012-09-01

    The in vivo subcellular localization of Mal de Rio Cuarto virus (MRCV, Fijivirus, Reoviridae) non-structural proteins fused to GFP was analyzed by confocal microscopy. P5-1 showed a cytoplasmic vesicular-like distribution that was lost upon deleting its PDZ binding TKF motif, suggesting that P5-1 interacts with cellular PDZ proteins. P5-2 located at the nucleus and its nuclear import was affected by the deletion of its basic C-termini. P7-1 and P7-2 also entered the nucleus and therefore, along with P5-2, could function as regulators of host gene expression. P6 located in the cytoplasm and in perinuclear cloud-like inclusions, was driven to P9-1 viroplasm-like structures and co-localized with P7-2, P10 and {alpha}-tubulin, suggesting its involvement in viroplasm formation and viral intracellular movement. Finally, P9-2 was N-glycosylated and located at the plasma membrane in association with filopodia-like protrusions containing actin, suggesting a possible role in virus cell-to-cell movement and spread.

  9. Insect pests of stored grain products

    International Nuclear Information System (INIS)

    The presence of insects in stored products is a worldwide recognized problem. In this report chemical and physical methods to control insect infestations in stored products are discussed. Special attention is given to the use of ionizing radiation to control insect pests in stored grains. The radiosensitivity of the most common insect pests at their different developmental stages is presented and discussed. The conclusions of this review are compiled in an executive summary. 62 refs

  10. Modern Stored-Product Insect Pest Management

    OpenAIRE

    Hagstrum David William; Flinn Paul Whitney

    2014-01-01

    Stored-product entomologists have a variety of new monitoring, decision-making, biological, chemical, and physical pest management tools available to them. Two types of stored-product insect populations are of interest: insects of immediate economic importance infesting commodities, and insects that live in food residues in equipment and facilities. The sampling and control methods change as grain and grain products move from field to consumer. There are also some changes in the major insect ...

  11. Symbiont-mediated functions in insect hosts

    OpenAIRE

    Su, Qi; Zhou, Xiaomao; Zhang, Youjun

    2013-01-01

    The bacterial endosymbionts occur in a diverse array of insect species and are usually rely within the vertical transmission from mothers to offspring. In addition to primary symbionts, plant sap-sucking insects may also harbor several diverse secondary symbionts. Bacterial symbionts play a prominent role in insect nutritional ecology by aiding in digestion of food or supplementing nutrients that insect hosts can’t obtain sufficient amounts from a restricted diet of plant phloem. Currently, s...

  12. Buckling failures in insect exoskeletons.

    Science.gov (United States)

    Parle, Eoin; Herbaj, Simona; Sheils, Fiona; Larmon, Hannah; Taylor, David

    2016-02-01

    Thin walled tubes are often used for load-bearing structures, in nature and in engineering, because they offer good resistance to bending and torsion at relatively low weight. However, when loaded in bending they are prone to failure by buckling. It is difficult to predict the loading conditions which cause buckling, especially for tubes whose cross sections are not simple shapes. Insights into buckling prevention might be gained by studying this phenomenon in the exoskeletons of insects and other arthropods. We investigated the leg segments (tibiae) of five different insects: the locust (Schistocerca gergaria), American cockroach (Periplaneta americana), death's head cockroach (Blaberus discoidalis), stick insect (Parapachymorpha zomproi) and bumblebee (Bombus terrestris audax). These were tested to failure in cantilever bending and modelled using finite element analysis (FEA). The tibiae of the locust and the cockroaches were found to be approximately circular in shape. Their buckling loads were well predicted by linear elastic FEA, and also by one of the analytical solutions available in the literature for elastic buckling. The legs of the stick insect are also circular in cross section but have several prominent longitudinal ridges. We hypothesised that these ridges might protect the legs against buckling but we found that this was not the case: the loads necessary for elastic buckling were not reached in practice because yield occurred in the material, causing plastic buckling. The legs of bees have a non-circular cross section due to a pollen-carrying feature (the corbicula). We found that this did not significantly affect their resistance to buckling. Our results imply that buckling is the dominant failure mode in the tibia of insects; it likely to be a significant consideration for other arthropods and any organisms with stiff exoskeletons. The interactions displayed here between material properties and cross sectional geometry may provide insights for the

  13. Buckling failures in insect exoskeletons.

    Science.gov (United States)

    Parle, Eoin; Herbaj, Simona; Sheils, Fiona; Larmon, Hannah; Taylor, David

    2016-02-01

    Thin walled tubes are often used for load-bearing structures, in nature and in engineering, because they offer good resistance to bending and torsion at relatively low weight. However, when loaded in bending they are prone to failure by buckling. It is difficult to predict the loading conditions which cause buckling, especially for tubes whose cross sections are not simple shapes. Insights into buckling prevention might be gained by studying this phenomenon in the exoskeletons of insects and other arthropods. We investigated the leg segments (tibiae) of five different insects: the locust (Schistocerca gergaria), American cockroach (Periplaneta americana), death's head cockroach (Blaberus discoidalis), stick insect (Parapachymorpha zomproi) and bumblebee (Bombus terrestris audax). These were tested to failure in cantilever bending and modelled using finite element analysis (FEA). The tibiae of the locust and the cockroaches were found to be approximately circular in shape. Their buckling loads were well predicted by linear elastic FEA, and also by one of the analytical solutions available in the literature for elastic buckling. The legs of the stick insect are also circular in cross section but have several prominent longitudinal ridges. We hypothesised that these ridges might protect the legs against buckling but we found that this was not the case: the loads necessary for elastic buckling were not reached in practice because yield occurred in the material, causing plastic buckling. The legs of bees have a non-circular cross section due to a pollen-carrying feature (the corbicula). We found that this did not significantly affect their resistance to buckling. Our results imply that buckling is the dominant failure mode in the tibia of insects; it likely to be a significant consideration for other arthropods and any organisms with stiff exoskeletons. The interactions displayed here between material properties and cross sectional geometry may provide insights for the

  14. Reducing the maladaptive attractiveness of solar panels to polarotactic insects.

    Science.gov (United States)

    Horváth, Gábor; Blahó, Miklós; Egri, Adám; Kriska, György; Seres, István; Robertson, Bruce

    2010-12-01

    Human-made objects (e.g., buildings with glass surfaces) can reflect horizontally polarized light so strongly that they appear to aquatic insects to be bodies of water. Insects that lay eggs in water are especially attracted to such structures because these insects use horizontal polarization of light off bodies of water to find egg-laying sites. Thus, these sources of polarized light can become ecological traps associated with reproductive failure and mortality in organisms that are attracted to them and by extension with rapid population declines or collapse. Solar panels are a new source of polarized light pollution. Using imaging polarimetry, we measured the reflection-polarization characteristics of different solar panels and in multiple-choice experiments in the field we tested their attractiveness to mayflies, caddis flies, dolichopodids, and tabanids. At the Brewster angle, solar panels polarized reflected light almost completely (degree of polarization d ≈ 100%) and substantially exceeded typical polarization values for water (d ≈ 30-70%). Mayflies (Ephemeroptera), stoneflies (Trichoptera), dolichopodid dipterans, and tabanid flies (Tabanidae) were the most attracted to solar panels and exhibited oviposition behavior above solar panels more often than above surfaces with lower degrees of polarization (including water), but in general they avoided solar cells with nonpolarizing white borders and white grates. The highly and horizontally polarizing surfaces that had nonpolarizing, white cell borders were 10- to 26-fold less attractive to insects than the same panels without white partitions. Although solar panels can act as ecological traps, fragmenting their solar-active area does lessen their attractiveness to polarotactic insects. The design of solar panels and collectors and their placement relative to aquatic habitats will likely affect populations of aquatic insects that use polarized light as a behavioral cue.

  15. Reducing the maladaptive attractiveness of solar panels to polarotactic insects.

    Science.gov (United States)

    Horváth, Gábor; Blahó, Miklós; Egri, Adám; Kriska, György; Seres, István; Robertson, Bruce

    2010-12-01

    Human-made objects (e.g., buildings with glass surfaces) can reflect horizontally polarized light so strongly that they appear to aquatic insects to be bodies of water. Insects that lay eggs in water are especially attracted to such structures because these insects use horizontal polarization of light off bodies of water to find egg-laying sites. Thus, these sources of polarized light can become ecological traps associated with reproductive failure and mortality in organisms that are attracted to them and by extension with rapid population declines or collapse. Solar panels are a new source of polarized light pollution. Using imaging polarimetry, we measured the reflection-polarization characteristics of different solar panels and in multiple-choice experiments in the field we tested their attractiveness to mayflies, caddis flies, dolichopodids, and tabanids. At the Brewster angle, solar panels polarized reflected light almost completely (degree of polarization d ≈ 100%) and substantially exceeded typical polarization values for water (d ≈ 30-70%). Mayflies (Ephemeroptera), stoneflies (Trichoptera), dolichopodid dipterans, and tabanid flies (Tabanidae) were the most attracted to solar panels and exhibited oviposition behavior above solar panels more often than above surfaces with lower degrees of polarization (including water), but in general they avoided solar cells with nonpolarizing white borders and white grates. The highly and horizontally polarizing surfaces that had nonpolarizing, white cell borders were 10- to 26-fold less attractive to insects than the same panels without white partitions. Although solar panels can act as ecological traps, fragmenting their solar-active area does lessen their attractiveness to polarotactic insects. The design of solar panels and collectors and their placement relative to aquatic habitats will likely affect populations of aquatic insects that use polarized light as a behavioral cue. PMID:20455911

  16. Radar, Insect Population Ecology, and Pest Management

    Science.gov (United States)

    Vaughn, C. R. (Editor); Wolf, W. (Editor); Klassen, W. (Editor)

    1979-01-01

    Discussions included: (1) the potential role of radar in insect ecology studies and pest management; (2) the potential role of radar in correlating atmospheric phenomena with insect movement; (3) the present and future radar systems; (4) program objectives required to adapt radar to insect ecology studies and pest management; and (5) the specific action items to achieve the objectives.

  17. 21 CFR 1250.95 - Insect control.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Insect control. 1250.95 Section 1250.95 Food and... SANITATION Sanitation Facilities and Conditions on Vessels § 1250.95 Insect control. Vessels shall be... generally accepted methods of insect control....

  18. Radioisotopes and food preservation against insects

    International Nuclear Information System (INIS)

    The book describes how to preserve food from harmful insects by using radioisotopes. It focusses on the impact of ionized radiation on the different stages of insect growth and on its metabolism and immunity. It also discusses the relationship between radiation doses and insect reproduction. It explains the various methods to detect the irradiated foods

  19. Insect stereopsis demonstrated using a 3D insect cinema

    OpenAIRE

    Vivek Nityananda; Ghaith Tarawneh; Ronny Rosner; Judith Nicolas; Stuart Crichton; Jenny Read

    2016-01-01

    Stereopsis - 3D vision – has become widely used as a model of perception. However, all our knowledge of possible underlying mechanisms comes almost exclusively from vertebrates. While stereopsis has been demonstrated for one invertebrate, the praying mantis, a lack of techniques to probe invertebrate stereopsis has prevented any further progress for three decades. We therefore developed a stereoscopic display system for insects, using miniature 3D glasses to present separate images to each ey...

  20. Insect diversity in the fossil record

    Science.gov (United States)

    Labandeira, C. C.; Sepkoski, J. J. Jr; Sepkoski JJ, J. r. (Principal Investigator)

    1993-01-01

    Insects possess a surprisingly extensive fossil record. Compilation of the geochronologic ranges of insect families demonstrates that their diversity exceeds that of preserved vertebrate tetrapods through 91 percent of their evolutionary history. The great diversity of insects was achieved not by high origination rates but rather by low extinction rates comparable to the low rates of slowly evolving marine invertebrate groups. The great radiation of modern insects began 245 million years ago and was not accelerated by the expansion of angiosperms during the Cretaceous period. The basic trophic machinery of insects was in place nearly 100 million years before angiosperms appeared in the fossil record.

  1. The Curious Connection Between Insects and Dreams

    OpenAIRE

    Klein, Barrett A.

    2011-01-01

    A majority of humans spend their waking hours surrounded by insects, so it should be no surprise that insects also appear in humans’ dreams as we sleep. Dreaming about insects has a peculiar history, marked by our desire to explain a dream’s significance and by the tactic of evoking emotions by injecting insects in dream-related works of art, film, music, and literature. I surveyed a scattered literature for examples of insects in dreams, first from the practices of dream interpretation, psyc...

  2. The α1,6-fucosyltransferase gene (fut8) from the Sf9 lepidopteran insect cell line: insights into fut8 evolution.

    Science.gov (United States)

    Juliant, Sylvie; Harduin-Lepers, Anne; Monjaret, François; Catieau, Béatrice; Violet, Marie-Luce; Cérutti, Pierre; Ozil, Annick; Duonor-Cérutti, Martine

    2014-01-01

    The core alpha1,6-fucosyltransferase (FUT8) catalyzes the transfer of a fucosyl moiety from GDP-fucose to the innermost asparagine-linked N-acetylglucosamine residue of glycoproteins. In mammals, this glycosylation has an important function in many fundamental biological processes and although no essential role has been demonstrated yet in all animals, FUT8 amino acid (aa) sequence and FUT8 activity are very well conserved throughout the animal kingdom. We have cloned the cDNA and the complete gene encoding the FUT8 in the Sf9 (Spodoptera frugiperda) lepidopteran cell line. As in most animal genomes, fut8 is a single-copy gene organized in different exons. The open reading frame contains 12 exons, a characteristic that seems to be shared by all lepidopteran fut8 genes. We chose to study the gene structure as a way to characterize the evolutionary relationships of the fut8 genes in metazoans. Analysis of the intron-exon organization in 56 fut8 orthologs allowed us to propose a model for fut8 evolution in metazoans. The presence of a highly variable number of exons in metazoan fut8 genes suggests a complex evolutionary history with many intron gain and loss events, particularly in arthropods, but not in chordata. Moreover, despite the high conservation of lepidoptera FUT8 sequences also in vertebrates and hymenoptera, the exon-intron organization of hymenoptera fut8 genes is order-specific with no shared exons. This feature suggests that the observed intron losses and gains may be linked to evolutionary innovations, such as the appearance of new orders. PMID:25333276

  3. Pyrrhocoricin, a proline-rich antimicrobial peptide derived from insect, inhibits the translation process in the cell-free Escherichia coli protein synthesis system.

    Science.gov (United States)

    Taniguchi, Masayuki; Ochiai, Akihito; Kondo, Hiroshi; Fukuda, Shun; Ishiyama, Yohei; Saitoh, Eiichi; Kato, Tetsuo; Tanaka, Takaaki

    2016-05-01

    Previous studies have shown that pyrrhocoricin, a proline-rich antimicrobial peptide (PrAMP), killed sensitive species in a dose-dependent manner by specifically binding to DnaK. Here, on the basis of the finding that DnaK-deficient Escherichia coli strains are susceptible to PrAMPs, we used pyrrhocoricin to investigate internal targets other than DnaK. Using conventional antibiotics (bleomycin, streptomycin, and fosfomycin) that have known modes of action, first, we validated the availability of an assay using a cell-free rapid translation system (RTS), which is an in vitro protein synthesis system based on E. coli lysate, for evaluating inhibition of protein synthesis. We found that, similarly to bleomycin and streptomycin, pyrrhocoricin inhibited GFP synthesis in RTS in a concentration-dependent manner. In addition, blockage of transcription and translation steps in RTS was individually estimated using RT-PCR after gene expression to determine mRNA products and using sodium dodecyl sulfate-polyacrylamide gel electrophoresis to determine the amounts of GFP expressed from purified mRNA, respectively. The results demonstrated that this inhibition of GFP synthesis by pyrrhocoricin did not occur at the transcription step but rather at the translation step, in a manner similar to that of GFP synthesis by streptomycin, an inhibitor of the translation step by causing misreading of tRNA. These results suggest that RTS is a powerful assay system for determining if antimicrobial peptides inhibit protein synthesis and its transcription and/or translation steps. This is the first study to have shown that pyrrhocoricin inhibited protein synthesis by specifically repressing the translation step. PMID:26472128

  4. The α1,6-fucosyltransferase gene (fut8 from the Sf9 lepidopteran insect cell line: insights into fut8 evolution.

    Directory of Open Access Journals (Sweden)

    Sylvie Juliant

    Full Text Available The core alpha1,6-fucosyltransferase (FUT8 catalyzes the transfer of a fucosyl moiety from GDP-fucose to the innermost asparagine-linked N-acetylglucosamine residue of glycoproteins. In mammals, this glycosylation has an important function in many fundamental biological processes and although no essential role has been demonstrated yet in all animals, FUT8 amino acid (aa sequence and FUT8 activity are very well conserved throughout the animal kingdom. We have cloned the cDNA and the complete gene encoding the FUT8 in the Sf9 (Spodoptera frugiperda lepidopteran cell line. As in most animal genomes, fut8 is a single-copy gene organized in different exons. The open reading frame contains 12 exons, a characteristic that seems to be shared by all lepidopteran fut8 genes. We chose to study the gene structure as a way to characterize the evolutionary relationships of the fut8 genes in metazoans. Analysis of the intron-exon organization in 56 fut8 orthologs allowed us to propose a model for fut8 evolution in metazoans. The presence of a highly variable number of exons in metazoan fut8 genes suggests a complex evolutionary history with many intron gain and loss events, particularly in arthropods, but not in chordata. Moreover, despite the high conservation of lepidoptera FUT8 sequences also in vertebrates and hymenoptera, the exon-intron organization of hymenoptera fut8 genes is order-specific with no shared exons. This feature suggests that the observed intron losses and gains may be linked to evolutionary innovations, such as the appearance of new orders.

  5. Fungal allelochemicals in insect pest management.

    Science.gov (United States)

    Holighaus, Gerrit; Rohlfs, Marko

    2016-07-01

    Interactions between insects and fungi are widespread, and important mediators of these interactions are fungal chemicals that can therefore be considered as allelochemicals. Numerous studies suggest that fungal chemicals can affect insects in many different ways. Here, we apply the terminology established by insect-plant ecologists for categorizing the effect of fungal allelochemicals on insects and for evaluating the application potential of these chemicals in insect pest management. Our literature survey shows that fungal volatile and non-volatile chemicals have an enormous potential to influence insect behavior and fitness. Many of them still remain to be discovered, but some recent examples of repellents and toxins could open up new ways for developing safe insect control strategies. However, we also identified shortcomings in our understanding of the chemical ecology of insect-fungus interactions and the way they have been investigated. In particular, the mode-of-action of fungal allelochemicals has often not been appropriately designated or examined, and the way in which induction by insects affects fungal chemical diversity is poorly understood. This review should raise awareness that in-depth ecological studies of insect-fungus interactions can reveal novel allelochemicals of particular benefit for the development of innovative insect pest management strategies. PMID:27147531

  6. Insects as alternative hosts for phytopathogenic bacteria.

    Science.gov (United States)

    Nadarasah, Geetanchaly; Stavrinides, John

    2011-05-01

    Phytopathogens have evolved specialized pathogenicity determinants that enable them to colonize their specific plant hosts and cause disease, but their intimate associations with plants also predispose them to frequent encounters with herbivorous insects, providing these phytopathogens with ample opportunity to colonize and eventually evolve alternative associations with insects. Decades of research have revealed that these associations have resulted in the formation of bacterial-vector relationships, in which the insect mediates dissemination of the plant pathogen. Emerging research, however, has highlighted the ability of plant pathogenic bacteria to use insects as alternative hosts, exploiting them as they would their primary plant host. The identification of specific bacterial genetic determinants that mediate the interaction between bacterium and insect suggests that these interactions are not incidental, but have likely arisen following the repeated association of microorganisms with particular insects over evolutionary time. This review will address the biology and ecology of phytopathogenic bacteria that interact with insects, including the traditional role of insects as vectors, as well as the newly emerging paradigm of insects serving as alternative primary hosts. Also discussed is one case where an insect serves as both host and vector, which may represent a transitionary stage in the evolution of insect-phytopathogen associations. PMID:21251027

  7. 人胰岛素原的N-糖基化修饰及在昆虫细胞中的表达%N-glycosylation and Expression of Human Proinsulin in Insect Cells

    Institute of Scientific and Technical Information of China (English)

    车凤玉; 刘子瑜; 张业顺; 张国政; 韦亚东

    2013-01-01

    Human insulin is a non-glycosylated protein hormone.Its in vivo biological half-life is very short.Since N-glycosylation can enhance a protein's biological activity and prolong its biological half-life,human proinsulin gene was reconstructed through DNA recombination,in which a conservative N-glycosylation site was added to the N-terminus of its B chain.The recombinant gene was cloned into ph/sp plasmid and transformed into E.coli AcDH10Bac to prepare recombinant baculoviral plasmid Bacmid-lg,which was subsequently used to transfect Sf21 cells to obtain the recombinant baculovirus carrying human proinsulin gene (Ig) with N-glycosylation sites.Western blotting displayed an N-glycosylated human proinsulin protein of approximately 20 kD molecular mass in Sf21 cells infected with recombinant virus.Moreover,a reduced molecular mass was detected in cellular expression product after adding tunicamycin.These research results showed that human proinsulin gene had been expressed and glycosylated successfully in insect cells.%人胰岛素为非糖基化修饰的蛋白质类激素,在生物体内的半衰期非常短.利用蛋白质经N-糖基化修饰后可以增强生物活性并延长其生物半衰期的特点,对人胰岛素原基因进行DNA重组改造,在其B链的N端添加保守性的N-糖基化位点后,克隆入ph/sp质粒,并转化至E coli AcDH10Bac细胞,获得重组杆状病毒质粒Bacmid-Ig,然后转染Sf21细胞,获得含有N-糖基化位点的人胰岛素原基因(Ig)的重组杆状病毒.用Western blotting方法在感染此重组病毒的Sf21细胞中检测到分子质量约20 kD的经过N-糖基化修饰的人胰岛素原蛋白,并且在添加衣霉素的细胞表达产物中检测到该蛋白质的分子质量变小.研究结果表明,人胰岛素原在昆虫细胞中获得了表达并且被糖基化修饰.

  8. Insect Protected Soybean MON 87701

    OpenAIRE

    Directorate, Issued by Health Canada's Food

    2014-01-01

    Health Canada has notified Monsanto Canada Inc. that it has no objection to the food use of Insect Protected Soybean MON 87701. The Department conducted a comprehensive assessment of this variety according to its Guidelines for the Safety Assessment of Novel Foods. These Guidelines are based upon internationally accepted principles for establishing the safety of foods with novel traits. The following provides a summary of the notification from Monsanto Canada Inc. a...

  9. Insect Pest Control Newsletter, No. 81, July 2013

    International Nuclear Information System (INIS)

    In response to requests from our readers, this introduction is mainly dedicated to the ongoing efforts to develop alternatives for insect reproductive sterilization and blood sterilization for their use in insect pest control programmes with a sterile insect technique (SIT) component. Radioisotope irradiators that are loaded with either cobalt-60 or caesium-137 producing gamma rays have been routinely used for many decades and have proven to be extremely reliable and safe for these purposes in successful area-wide insect eradication or suppression programmes. These include industrial panoramic-type irradiators in larger programmes, all the way to smaller self-contained irradiators. Nevertheless, the transboundary shipment of self-contained gamma irradiators or radioactive material has become logistically more complex due to security issues. This situation was exacerbated when the production of the Gamma Cell 220 (GC220), the source most commonly used for irradiating insects for sterilization purposes, was discontinued. These events may have created the impression that the use of gamma radiation has become a less viable option, unattainable for insect pest control programmes that want to integrate the SIT. Nevertheless, some of the biggest SIT operational programmes have in recent years been equipped with new self-contained cobalt-60 sources, including the SIT programme against the pink bollworm in Phoenix, Arizona; El Pino Mediterranean fruit fly facility in Guatemala; and the screwworm programme in Panama. Thus these larger and more expensive irradiators, together with panoramic units (that are also costlier than self-contained gamma irradiators) have remained over the years a valid option, especially for larger operational programmes. In addition, the reloading of smaller units with new cobalt or the purchase of refurbished used self-contained irradiators remain viable alternatives

  10. Gut immunity in Lepidopteran insects.

    Science.gov (United States)

    Wu, Kai; Yang, Bing; Huang, Wuren; Dobens, Leonard; Song, Hongsheng; Ling, Erjun

    2016-11-01

    Lepidopteran insects constitute one of the largest fractions of animals on earth, but are considered pests in their relationship with man. Key to the success of this order of insects is its ability to digest food and absorb nutrition, which takes place in the midgut. Because environmental microorganisms can easily enter Lepidopteran guts during feeding, the innate immune response guards against pathogenic bacteria, virus and microsporidia that can be devoured with food. Gut immune responses are complicated by both resident gut microbiota and the surrounding peritrophic membrane and are distinct from immune responses in the body cavity, which depend on the function of the fat body and hemocytes. Due to their relevance to agricultural production, studies of Lepidopteran insect midgut and immunity are receiving more attention, and here we summarize gut structures and functions, and discuss how these confer immunity against different microorganisms. It is expected that increased knowledge of Lepidopteran gut immunity may be utilized for pest biological control in the future. PMID:26872544

  11. Emergent dynamics of laboratory insect swarms

    Science.gov (United States)

    Kelley, Douglas H.; Ouellette, Nicholas T.

    2013-01-01

    Collective animal behaviour occurs at nearly every biological size scale, from single-celled organisms to the largest animals on earth. It has long been known that models with simple interaction rules can reproduce qualitative features of this complex behaviour. But determining whether these models accurately capture the biology requires data from real animals, which has historically been difficult to obtain. Here, we report three-dimensional, time-resolved measurements of the positions, velocities, and accelerations of individual insects in laboratory swarms of the midge Chironomus riparius. Even though the swarms do not show an overall polarisation, we find statistical evidence for local clusters of correlated motion. We also show that the swarms display an effective large-scale potential that keeps individuals bound together, and we characterize the shape of this potential. Our results provide quantitative data against which the emergent characteristics of animal aggregation models can be benchmarked.

  12. A new family of insect tyramine receptors

    DEFF Research Database (Denmark)

    Cazzamali, Giuseppe; Klærke, Dan Arne; Grimmelikhuijzen, Cornelis J P

    2005-01-01

    The Drosophila Genome Project database contains a gene, CG7431, annotated to be an "unclassifiable biogenic amine receptor." We have cloned this gene and expressed it in Chinese hamster ovary cells. After testing various ligands for G protein-coupled receptors, we found that the receptor was...... specifically activated by tyramine (EC(50), 5x10(-7)M) and that it showed no cross-reactivity with beta-phenylethylamine, octopamine, dopa, dopamine, adrenaline, noradrenaline, tryptamine, serotonin, histamine, and a library of 20 Drosophila neuropeptides (all tested in concentrations up to 10(-5) or 10(-4)M......-like receptor genes in the genomic databases from the malaria mosquito Anopheles gambiae and the honeybee Apis mellifera. These four tyramine or tyramine-like receptors constitute a new receptor family that is phylogenetically distinct from the previously identified insect octopamine/tyramine receptors. The...

  13. Effects of ionizing radiations on insects

    International Nuclear Information System (INIS)

    The most traditional effects caused by irradiation are development and morphogenesis disorders since on the whole the sensitivity of the developing organism to ionizing radiations is all the greater as the growth rate is faster. During the development of higher insects two categories of cell divide: larval cells on the one hand, which differentiate immediately after segmentation and give rise to larval organisms, and embryonic cells on the other which divide actively to form various islets or imaginal discs destined, each to its own extent, to provide the organs of the adult. Two cell categories thus coexist in the larva, one undergoing differentiation and the other multiplication, the radiosensitivity of which will be quite different for this very reason and will account at least partly, where the lethal effect of ionizing radiations is concerned, for the results observed. Three chapters deal in turn with effects on longevity, on regeneration and restoration and on morphogenesis and development. Strong doses give rise beyond a certain threshold to the appearance of acute radiodermatitis; their clinical signs and different degrees of seriousness liken them to burns of a special type

  14. Impacts of urbanization process on insect diversity

    Directory of Open Access Journals (Sweden)

    Shuisong Ye

    2013-05-01

    Full Text Available Rapid worldwide urbanization during the last century has led to more than half the world’s population living in urban regions. Studies of how urbanization affects insect diversity have focused on the following: insect abundance, distribution, extinction, food habits and ecosystem services. Native insect populations have declined greatly in urban areas, where studies of their spatial distribution have revealed that abundance decreases along what is termed the rural–city center gradient (RCG, many native insects even extinct with urbanization process. Most specialist insect communities have declined in abundance due to urbanization, while some generalist species, such as aphids, cockroaches and termites, have increased slightly in abundance. It is also the case that herbivorous, parasitic, saprophagous and flower-visiting insects are much more negatively influenced by urbanization than predator insects. This has a significant effect on the ecosystem services of insects. The decline of many insects due to urbanization can be attributed to environmental pollution (including air pollution, water pollution, light pollution, and heat pollution, habitat fragmentation, road hardening, clustering of buildings, and occurrence of introduced invasive species. As urbanization continues, measures should be taken to protect insects in urban areas. This will entail improving basic scientific research on the problem, construction of suitable habitats, and informing the general public of the benefits of environmental protection.

  15. Calcium signaling mediates cold sensing in insect tissues.

    Science.gov (United States)

    Teets, Nicholas M; Yi, Shu-Xia; Lee, Richard E; Denlinger, David L

    2013-05-28

    The ability to rapidly respond to changes in temperature is a critical adaptation for insects and other ectotherms living in thermally variable environments. In a process called rapid cold hardening (RCH), insects significantly enhance cold tolerance following brief (i.e., minutes to hours) exposure to nonlethal chilling. Although the ecological relevance of RCH is well-established, the underlying physiological mechanisms that trigger RCH are poorly understood. RCH can be elicited in isolated tissues ex vivo, suggesting cold-sensing and downstream hardening pathways are governed by brain-independent signaling mechanisms. We previously provided preliminary evidence that calcium is involved in RCH, and here we firmly establish that calcium signaling mediates cold sensing in insect tissues. In tracheal cells of the freeze-tolerant goldenrod gall fly, Eurosta solidaginis, chilling to 0 °C evoked a 40% increase in intracellular calcium concentration as determined by live-cell confocal imaging. Downstream of calcium entry, RCH conditions significantly increased the activity of calcium/calmodulin-dependent protein kinase II (CaMKII) while reducing phosphorylation of the inhibitory Thr306 residue. Pharmacological inhibitors of calcium entry, calmodulin activation, and CaMKII activity all prevented ex vivo RCH in midgut and salivary gland tissues, indicating that calcium signaling is required for RCH to occur. Similar results were obtained for a freeze-intolerant species, adults of the flesh fly, Sarcophaga bullata, suggesting that calcium-mediated cold sensing is a general feature of insects. Our results imply that insect tissues use calcium signaling to instantly detect decreases in temperature and trigger downstream cold-hardening mechanisms.

  16. Disruption of insect isoprenoid biosynthesis with pyridinium bisphosphonates.

    Science.gov (United States)

    Sen, Stephanie E; Wood, Lyndsay; Jacob, Reshma; Xhambazi, Alisa; Pease, Britanny; Jones, Alexis; Horsfield, Taylor; Lin, Alice; Cusson, Michel

    2015-08-01

    Farnesyl diphosphate synthase (FPPS) catalyzes the condensation of the non-allylic diphosphate, isopentenyl diphosphate (IPP; C5), with the allylic diphosphate primer dimethylallyl diphosphate (DMAPP; C5) to generate the C15 prenyl chain (FPP) used for protein prenylation as well as sterol and terpene biosynthesis. Here, we designed and prepared a series of pyridinium bisphosphonate (PyrBP) compounds, with the aim of selectively inhibiting FPPS of the lepidopteran insect order. FPPSs of Drosophila melanogaster and the spruce budworm, Choristoneura fumiferana, were inhibited by several PyrBPs, and as hypothesized, larger bisphosphonates were more selective for the lepidopteran protein and completely inactive towards dipteran and vertebrate FPPSs. Cell growth of a D. melanogaster cell line was adversely affected by exposure to PyrPBs that were strongly inhibitory to insect FPPS, although their effect was less pronounced than that observed upon exposure to the electron transport disrupter, chlorfenapyr. To assess the impact of PyrBPs on lepidopteran insect growth and development, we performed feeding and topical studies, using the tobacco hornworm, Manduca sexta, as our insect model. The free acid form of a PyrBP and a known bisphosphonate inhibitor of vertebrate FPPS, alendronate, had little to no effect on larval M. sexta; however, the topical application of more lipophilic ester PyrBPs caused decreased growth, incomplete larval molting, cuticle darkening at the site of application, and for those insects that survived, the formation of larval-pupal hybrids. To gain a better understanding of the structural differences that produce selective lepidopteran FPPS inhibition, homology models of C. fumiferana and D. melanogaster FPPS (CfFPPS2, and DmFPPS) were prepared. Docking of substrates and PyrBPs demonstrates that differences at the -3 and -4 positions relative to the first aspartate rich motif (FARM) are important factors in the ability of the lepidopteran enzyme to

  17. Herbivory increases diversification across insect clades.

    Science.gov (United States)

    Wiens, John J; Lapoint, Richard T; Whiteman, Noah K

    2015-09-24

    Insects contain more than half of all living species, but the causes of their remarkable diversity remain poorly understood. Many authors have suggested that herbivory has accelerated diversification in many insect clades. However, others have questioned the role of herbivory in insect diversification. Here, we test the relationships between herbivory and insect diversification across multiple scales. We find a strong, positive relationship between herbivory and diversification among insect orders. However, herbivory explains less variation in diversification within some orders (Diptera, Hemiptera) or shows no significant relationship with diversification in others (Coleoptera, Hymenoptera, Orthoptera). Thus, we support the overall importance of herbivory for insect diversification, but also show that its impacts can vary across scales and clades. In summary, our results illuminate the causes of species richness patterns in a group containing most living species, and show the importance of ecological impacts on diversification in explaining the diversity of life.

  18. Insect stereopsis demonstrated using a 3D insect cinema.

    Science.gov (United States)

    Nityananda, Vivek; Tarawneh, Ghaith; Rosner, Ronny; Nicolas, Judith; Crichton, Stuart; Read, Jenny

    2016-01-01

    Stereopsis - 3D vision - has become widely used as a model of perception. However, all our knowledge of possible underlying mechanisms comes almost exclusively from vertebrates. While stereopsis has been demonstrated for one invertebrate, the praying mantis, a lack of techniques to probe invertebrate stereopsis has prevented any further progress for three decades. We therefore developed a stereoscopic display system for insects, using miniature 3D glasses to present separate images to each eye, and tested our ability to deliver stereoscopic illusions to praying mantises. We find that while filtering by circular polarization failed due to excessive crosstalk, "anaglyph" filtering by spectral content clearly succeeded in giving the mantis the illusion of 3D depth. We thus definitively demonstrate stereopsis in mantises and also demonstrate that the anaglyph technique can be effectively used to deliver virtual 3D stimuli to insects. This method opens up broad avenues of research into the parallel evolution of stereoscopic computations and possible new algorithms for depth perception. PMID:26740144

  19. Impacts of urbanization process on insect diversity

    OpenAIRE

    Shuisong Ye; Yan Fang; Kai Li

    2013-01-01

    Rapid worldwide urbanization during the last century has led to more than half the world’s population living in urban regions. Studies of how urbanization affects insect diversity have focused on the following: insect abundance, distribution, extinction, food habits and ecosystem services. Native insect populations have declined greatly in urban areas, where studies of their spatial distribution have revealed that abundance decreases along what is termed the rural–city center gradient (RCG), ...

  20. Forests and climate change - lessons from insects

    OpenAIRE

    Battisti A

    2008-01-01

    The climate change may indirectly affects the forest ecosystems through the activity of phytophagous insects. The climate change has been claimed to be responsible of the range expansion northward and upward of several insect species of northern temperate forests, as well as of changes in the seasonal phenology. Several papers have dealt with the prediction of the most likely consequences of the climate change on the phytophagous insects, including some of the most important forest pests. Inc...

  1. Arbuscular mycorrhizal fungi affect phytophagous insect specialism

    OpenAIRE

    Gange, Alan; Stagg, P.G.; Ward, L. K.

    2002-01-01

    The majority of phytophagous insects eat very few plant species, yet the ecological and evolutionary forces that have driven such specialism are not entirely understood. The hypothesis that arbuscular mycorrhizal (AM) fungi can determine phytophagous insect specialism, through differential effects on insect growth, was tested using examples from the British flora. In the UK, plant families and species in the family Lamiaceae that are strongly mycorrhizal have higher proportions of specialist ...

  2. Social-insect fungus farming

    DEFF Research Database (Denmark)

    Aanen, Duur Kornelis; Boomsma, Jacobus Jan

    2006-01-01

    basidiomycete genus Termitomyces - whereas the ants are associated with a larger diversity of fungal lineages (all basidiomycetes). The ants and termites forage for plant material to provision their fungus gardens. Their crops convert this carbon-rich plant material into nitrogen-rich fungal biomass to provide...... the farming insects with most of their food ( Figure 1 ). No secondary reversals to the ancestral life style are known in either group, which suggests that the transitions to farming were as drastically innovative and irreversible as when humans made this step about 10,000 years ago....

  3. Insect control by using sterile male technique

    International Nuclear Information System (INIS)

    The sterile male technique used in insect control is presented as an alternative for chemical control of pest insect. Description and effects of sterile male technique on morphology and physiology of different classes of pest insects are given. Prerequisite conditions necessary to work out SMT are presented. As an example of the application of this technique: control of Ephestia Cartella is studied. Gamma radiation effects on deformation, sterilization and longevity of the male insect as well as fecondity and fertility with respects of gamma irradiation are presented. 11 refs. 3 tabs

  4. Noise in an insect outbreak model

    CERN Document Server

    Bao Quan; Wang Xian Ju; Liu Guo Tao; We De Hua; Xie Hui Zhang; Liu Liang Gang

    2003-01-01

    We study the steady state properties of an insect (spruce budworm) outbreak model in the presence of Gaussian white noise. Based on the corresponding Fokker-Planck equation the steady state solution of the probability distribution function and its extrema have been investigated. It was found that fluctuations of the insect birth rate reduces the population of the insects while fluctuations of predation rate and the noise correlation can prevent the population of the insects from going into extinction. Noise in the model can induce a phase transition.

  5. Review on Nutritive Value of Edible Insects

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    As an importam bio-resource, insect resources have not been put into full play as healthy food. Based on study and analysis, the nutritive value of edible insects was reviewed. The results showed that insects have rich protein (20%-70%), amino acid (30%-60%),fat (10%-50%),fatty acid, carbonhydrate (2%-10%), mineral elements, vitamins and other activated elements which are good for human 's health. As protein resources, the nutritive value of edible insects is as good as animal and plant resources. Insec...

  6. Insect Flight: Aerodynamics, Efficiency, and Evolution

    Science.gov (United States)

    Wang, Z. Jane

    2007-11-01

    Insects, like birds and fish, locomote via interactions between fluids and flapping wings. Their motion is governed by the Navier-Stokes equation coupled to moving boundaries. In this talk, I will first describe how dragonflies fly: their wing motions and the flows and forces they generate. I will then consider insects in several species and discuss three questions: 1) Is insect flight optimal? 2) How does the efficiency of flapping flight compare to classical fixed-wing flight? 3) How might aerodynamic effects have influenced the evolution of insect flight?

  7. Protocol for Heterologous Expression of Insect Odourant Receptors in Drosophila

    OpenAIRE

    Gonzalez, Francisco; Witzgall, Peter; Walker, William B.

    2016-01-01

    Insect olfactory receptors (ORs) are tuned to volatile chemicals, they are expressed in the membrane of olfactory sensory neurons (OSNs), housed in sensilla on the antenna. The olfactory apparatus is under strong selection and ORs are tuned to vital chemical signals, mediating social communication, feeding and oviposition, and avoidance of predators and pathogens. An emerging technique to reliably and efficiently identify the key ligands of ORs is to express single ORs in heterologous cell sy...

  8. Ovariole structure of the cochineal scale insect, Dactylophis coccus.

    Science.gov (United States)

    Ramírez-Cruz, A; Llanderal-Cázares, C; Racotta, R

    2008-01-01

    The ovaries of the adult cochineal scale insect, Dactylopius coccus Costa (Hemiptera: Coccoidea: Dactylopiidae) are made up of more than 400 short ovarioles of the telotrophic type. The ovarioles develop asynchronously. The ovarioles consist of a germarium with six or seven nurse cells, a vitellarium with an oocyte, and pedicel. A terminal filament is lacking. A maturing oocyte was attached to the trophic core by the trophic cord during previtellogenesis and most of vitellogenesis. PMID:20337555

  9. Large-scale recoding of an arbovirus genome to rebalance its insect versus mammalian preference.

    Science.gov (United States)

    Shen, Sam H; Stauft, Charles B; Gorbatsevych, Oleksandr; Song, Yutong; Ward, Charles B; Yurovsky, Alisa; Mueller, Steffen; Futcher, Bruce; Wimmer, Eckard

    2015-04-14

    The protein synthesis machineries of two distinct phyla of the Animal kingdom, insects of Arthropoda and mammals of Chordata, have different preferences for how to best encode proteins. Nevertheless, arboviruses (arthropod-borne viruses) are capable of infecting both mammals and insects just like arboviruses that use insect vectors to infect plants. These organisms have evolved carefully balanced genomes that can efficiently use the translational machineries of different phyla, even if the phyla belong to different kingdoms. Using dengue virus as an example, we have undone the genome encoding balance and specifically shifted the encoding preference away from mammals. These mammalian-attenuated viruses grow to high titers in insect cells but low titers in mammalian cells, have dramatically increased LD50s in newborn mice, and induce high levels of protective antibodies. Recoded arboviruses with a bias toward phylum-specific expression could form the basis of a new generation of live attenuated vaccine candidates.

  10. Activation of mammalian retinoid X receptors by the insect growth regulator methoprene.

    OpenAIRE

    Harmon, M A; Boehm, M F; Heyman, R A; Mangelsdorf, D J

    1995-01-01

    We report that methoprene and its derivatives can stimulate gene transcription in vertebrates by acting through the retinoic acid-responsive transcription factors, the retinoid X receptors (RXRs). Methoprene is an insect growth regulator in domestic and agricultural use as a pesticide. At least one metabolite of methoprene, methoprene acid, directly binds to RXR and is a transcriptional activator in both insect and mammalian cells. Unlike the endogenous RXR ligand, 9-cis-retinoic acid, this a...

  11. Mode of action of Bacillus thuringiensis Cry and Cyt toxins and their potential for insect control

    OpenAIRE

    Bravo, Alejandra; Gill, Sarjeet S.; Soberón, Mario

    2006-01-01

    Bacillus thuringiensis Cry and Cyt protein families are a diverse group of proteins with activity against insects of different orders - Lepidoptera, Coleoptera, Diptera and also against other invertebrates such as nematodes. Their primary action is to lyse midgut epithelial cells by inserting into the target membrane and forming pores. Among this group of proteins, members of the 3-Domain Cry family are used worldwide for insect control, and their mode of action has been characterized in some...

  12. Postembryonic RNAi in Heterorhabditis bacteriophora: a nematode insect parasite and host for insect pathogenic symbionts

    Directory of Open Access Journals (Sweden)

    Sternberg Paul W

    2007-09-01

    Full Text Available Abstract Background Heterorhabditis bacteriophora is applied throughout the world for the biological control of insects and is an animal model to study interspecies interactions, e.g. mutualism, parasitism and vector-borne disease. H. bacteriophora nematodes are mutually associated with the insect pathogen, Photorhabdus luminescens. The developmentally arrested infective juvenile (IJ stage nematode (vector specifically transmits Photorhabdus luminescens bacteria (pathogen in its gut mucosa to the haemocoel of insects (host. The nematode vector and pathogen alone are not known to cause insect disease. RNA interference is an excellent reverse genetic tool to study gene function in C. elegans, and it would be useful in H. bacteriophora to exploit the H. bacteriophora genome project, currently in progress. Results Soaking L1 stage H. bacteriophora with seven dsRNAs of genes whose C. elegans orthologs had severe RNAi phenotypes resulted in highly penetrant and obvious developmental and reproductive abnormalities. The efficacy of postembryonic double strand RNA interference (RNAi was evident by abnormal gonad morphology and sterility of adult H. bacteriophora and C. elegans presumable due to defects in germ cell proliferation and gonad development. The penetrance of RNAi phenotypes in H. bacteriophora was high for five genes (87–100%; Hba-cct-2, Hba-daf-21, Hba-icd-1; Hba-nol-5, and Hba-W01G7.3 and moderate for two genes (usually 30–50%; Hba-rack-1 and Hba-arf-1. RNAi of three additional C. elegans orthologs for which RNAi phenotypes were not previously detected in C. elegans, also did not result in any apparent phenotypes in H. bacteriophora. Specific and severe reduction in transcript levels in RNAi treated L1s was determined by quantitative real-time RT-PCR. These results suggest that postembryonic RNAi by soaking is potent and specific. Conclusion Although RNAi is conserved in animals and plants, RNAi using long dsRNA is not. These results

  13. Insects diversity in lima bean (Phaseolus lunatus

    Directory of Open Access Journals (Sweden)

    WIWIN SETIAWATI

    2005-10-01

    Full Text Available Lima bean (Phaseolus lunatus is a vegetable which usually made as a home yard plant for Indonesian people to fulfill their daily needs. This plant has not been produced in the large number by the farmer. So it is hard to find in the market. Lima bean is light by many kind of insect. Inventory, identification and the study of insect taxon to this plant is being done to collect some information about the insect who life in the plant. The research was done in Balitsa experiment garden in the district of Lembang in Bandung regency on November 2003-February 2004, the experiment start at 4 weeks age, at the height of 1260 m over the sea level. The observation was made systematically by absolute method (D-vac macine and relative method (sweeping net. The research so that there were 26 species of phytofagous insect, 9 species of predator insect, 6 species of parasitoid insect, 4 species of pollinator and 14 species of scavenger insect. According to the research the highest species number was got in the 8th week (3rd sampling, which had 27 variety of species, so the highest diversity was also got in this with 2,113 point. Aphididae and Cicadellidae was the most insect found in roay plant. The research also had high number of species insect so the diversity of insect and evenness become high. A community will have the high stability if it is a long with the high diversity. High evenness in community that has low species dominance and high species number of insect so the high of species richness.

  14. Social insect symbionts: evolution in homeostatic fortresses

    DEFF Research Database (Denmark)

    Hughes, David P; Pierce, Naomi E; Boomsma, Jacobus J

    2008-01-01

    The massive environmentally buffered nests of some social insects can contain millions of individuals and a wide variety of parasites, commensals and mutualists. We suggest that the ways in which these homeostatic fortress environments affect the evolution of social insect symbionts are relevant...

  15. Insect and pest control newsletter. No. 56

    International Nuclear Information System (INIS)

    This Newsletter announces research coordination meetings, status of existing research coordinated research programmes on the use of nuclear applications such as the sterile insect technique (SIT) in insect and pest control. Training courses as well as new coordinated research programmes in the pipeline are also highlighted

  16. Insect and pest control newsletter. No. 55

    International Nuclear Information System (INIS)

    This Newsletter announces research coordination meetings, status of existing research coordinated research programmes on the use of nuclear applications such as the sterile insect technique (SIT) in insect and pest control. Training courses as well as new coordinated research programmes in the pipeline are also highlighted

  17. Insect and pest control newsletter. No. 53

    International Nuclear Information System (INIS)

    This Newsletter announces research coordination meetings, status of existing research coordinated research programmes on the use of nuclear applications such as the sterile insect technique (SIT) in insect and pest control. Training courses as well as new coordinated research programmes in the pipeline are also highlighted

  18. 7 CFR 51.2290 - Insect injury.

    Science.gov (United States)

    2010-01-01

    ... Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE REGULATIONS AND STANDARDS UNDER THE AGRICULTURAL MARKETING ACT OF 1946... means that the insect, web, frass or other evidence of insects is present on the portion of kernel....

  19. Insect and pest control newsletter. No. 50

    International Nuclear Information System (INIS)

    This Newsletter announces research coordination meetings, status of existing research coordinated research programmes on the use of nuclear applications such as the sterile insect technique (SIT) in insect and pest control. Training courses as well as new coordinated research programmes in the pipeline are also highlighted

  20. Insect and pest control newsletter. No. 51

    International Nuclear Information System (INIS)

    This Newsletter announces research coordination meetings, status of existing research coordinated research programmes on the use of nuclear applications such as the sterile insect technique (SIT) in insect and pest control. Training courses as well as new coordinated research programmes in the pipeline are also highlighted

  1. Insects and Spiders. Environmental Education Curriculum.

    Science.gov (United States)

    Topeka Public Schools, KS.

    This unit is designed to provide information on insects and spiders that special education students are capable of understanding. The activities are aimed at level 2 and level 3 educable mentally retarded classes. There are four topics: (1) Characteristics and Life Cycles of Insects; (2) Characteristics of Spiders; (3) Habitats and Food Sources of…

  2. Applications of genome editing in insects

    Science.gov (United States)

    Insect genome editing was first reported 1991 in Drosophila melanogaster but the technology used was not portable to other species. Not until the recent development of facile, engineered DNA endonuclease systems has gene editing become widely available to insect scientists. Most applications in inse...

  3. Testing mechanistic models of growth in insects.

    Science.gov (United States)

    Maino, James L; Kearney, Michael R

    2015-11-22

    Insects are typified by their small size, large numbers, impressive reproductive output and rapid growth. However, insect growth is not simply rapid; rather, insects follow a qualitatively distinct trajectory to many other animals. Here we present a mechanistic growth model for insects and show that increasing specific assimilation during the growth phase can explain the near-exponential growth trajectory of insects. The presented model is tested against growth data on 50 insects, and compared against other mechanistic growth models. Unlike the other mechanistic models, our growth model predicts energy reserves per biomass to increase with age, which implies a higher production efficiency and energy density of biomass in later instars. These predictions are tested against data compiled from the literature whereby it is confirmed that insects increase their production efficiency (by 24 percentage points) and energy density (by 4 J mg(-1)) between hatching and the attainment of full size. The model suggests that insects achieve greater production efficiencies and enhanced growth rates by increasing specific assimilation and increasing energy reserves per biomass, which are less costly to maintain than structural biomass. Our findings illustrate how the explanatory and predictive power of mechanistic growth models comes from their grounding in underlying biological processes.

  4. What Do Elementary Students Know about Insects?

    Science.gov (United States)

    Barrow, Lloyd H.

    2002-01-01

    Presents an interview-based study of (n=56) elementary school students. Determines students' understanding about insect characteristics, life cycles, environmental conditions, and impact on humans. Suggests building units of instruction based on students' personal questions about insects. (Contains 16 references.) (Author/YDS)

  5. Estimating Aquatic Insect Populations. Introduction to Sampling.

    Science.gov (United States)

    Chihuahuan Desert Research Inst., Alpine, TX.

    This booklet introduces high school and junior high school students to the major groups of aquatic insects and to population sampling techniques. Chapter 1 consists of a short field guide which can be used to identify five separate orders of aquatic insects: odonata (dragonflies and damselflies); ephemeroptera (mayflies); diptera (true flies);…

  6. Insect and pest control newsletter. No. 52

    International Nuclear Information System (INIS)

    This Newsletter announces research coordination meetings, status of existing research coordinated research programmes on the use of nuclear applications such as the sterile insect technique (SIT) in insect and pest control. Training courses as well as new coordinated research programmes in the pipeline are also highlighted

  7. Insect and pest control newsletter. No. 54

    International Nuclear Information System (INIS)

    This Newsletter announces research coordination meetings, status of existing research coordinated research programmes on the use of nuclear applications such as the sterile insect technique (SIT) in insect and pest control. Training courses as well as new coordinated research programmes in the pipeline are also highlighted

  8. Diversity in protein glycosylation among insect species.

    Directory of Open Access Journals (Sweden)

    Gianni Vandenborre

    Full Text Available BACKGROUND: A very common protein modification in multicellular organisms is protein glycosylation or the addition of carbohydrate structures to the peptide backbone. Although the Class of the Insecta is the largest animal taxon on Earth, almost all information concerning glycosylation in insects is derived from studies with only one species, namely the fruit fly Drosophila melanogaster. METHODOLOGY/PRINCIPAL FINDINGS: In this report, the differences in glycoproteomes between insects belonging to several economically important insect orders were studied. Using GNA (Galanthus nivalis agglutinin affinity chromatography, different sets of glycoproteins with mannosyl-containing glycan structures were purified from the flour beetle (Tribolium castaneum, the silkworm (Bombyx mori, the honeybee (Apis mellifera, the fruit fly (D. melanogaster and the pea aphid (Acyrthosiphon pisum. To identify and characterize the purified glycoproteins, LC-MS/MS analysis was performed. For all insect species, it was demonstrated that glycoproteins were related to a broad range of biological processes and molecular functions. Moreover, the majority of glycoproteins retained on the GNA column were unique to one particular insect species and only a few glycoproteins were present in the five different glycoprotein sets. Furthermore, these data support the hypothesis that insect glycoproteins can be decorated with mannosylated O-glycans. CONCLUSIONS/SIGNIFICANCE: The results presented here demonstrate that oligomannose N-glycosylation events are highly specific depending on the insect species. In addition, we also demonstrated that protein O-mannosylation in insect species may occur more frequently than currently believed.

  9. Notes on collecting flower-visiting insects

    NARCIS (Netherlands)

    Willemstein, S.C.

    1974-01-01

    Flower-visiting insects may play a role in the pollination of the flowers they visit. An important indication for this is the pollen they carry on their body. The transport of pollen does not prove pollination without observations of the behaviour of the insects on the flowers, but at least it offer

  10. Feeding Studies of Irradiated Foods with Insects

    International Nuclear Information System (INIS)

    Insects are of value to man in many scientific studies. Microsomal detoxication systems exist in both insects and mammals. In the preliminary investigations it was found that irradiated cocoa beans and white and red kidney beans (Phaseolus spp.) did not significantly change the percentage of egg-hatch in the insects tested. In more detailed investigations food samples that are susceptible to insect spoilage and are representatives of widely consumed human foods were fed to various insect species. The development, sex distortion and reproductivity of the insects were investigated. Cytogenetic aberrations as related to dominant lethality were studied in insects with reasonably clear chromosomal patterns. The meiosis stage was examined, using the squash technique and Aceto-orcein staining. Black beans, Phaseolus spp., irradiated with up to 200 krad of gamma rays did not apparently change the percentage of survival and the sex ratio of the bean weevil, Zabrotes subfasciatus. Dominant lethality in the German cockroach, Blatella germanica, fed on irradiated black beans did not apparently occur when considering the results of cytological investigation and the number of offspring obtained. Dried sardine samples irradiated with up to 400 krad of gamma rays neither apparently affected the survival nor caused sex distortion in the cheese skipper, Piophila casei. This irradiated product apparently did not induce dominant lethality in the German cockroach as tested. Coffee processed from coffee beans that had been irradiated with up to 100 krad of gamma rays did not apparently cause adverse effects on the experimental insects. (author)

  11. Turfgrass Cultural Practices and Insect Pest Management

    OpenAIRE

    Alston, Diane; Kopp, Kelly

    2010-01-01

    There are a number of insects that can cause aesthetic and economic loss to turfgrass in Utah – in home lawns as well as in athletic fields and on recreational lands. Good turfgrass cultural practices are the primary way to prevent insect infestation and turfgrass damage.

  12. Perspectives on the state of insect transgenics

    Science.gov (United States)

    Genetic transformation is a critical component to the fundamental genetic analysis of insect species, and holds great promise for establishing strains that improve population control and behavior for practical application. This is especially so for insects that are disease vectors, many of which a...

  13. Modern insect control: Nuclear techniques and biotechnology

    International Nuclear Information System (INIS)

    The Symposium dealt primarily with genetic methods of insect control, including sterile insect technique (SIT), F1 sterility, compound chromosomes, translocations and conditional lethals. Research and development activities on various aspects of these control technologies were reported by participants during the Symposium. Of particular interest was development of F1 sterility as a practical method of controlling pest Lepidoptera. Genetic methods of insect control are applicable only on an area wide basis. They are species specific and thus do not reduce populations of beneficial insects or cause other environmental problems. Other papers presented reported on the potential use of radiation as a quarantine treatment for commodities in international trade and the use of radioisotopes as ''tags'' in studying insects

  14. A call to insect scientists: Challenges and opportunities of managing insect communities under climate change

    Science.gov (United States)

    Hellmann, Jessica J.; Grundel, Ralph; Hoving, Chris; Schuurman, Gregor W.

    2016-01-01

    As climate change moves insect systems into uncharted territory, more knowledge about insect dynamics and the factors that drive them could enable us to better manage and conserve insect communities. Climate change may also require us revisit insect management goals and strategies and lead to a new kind of scientific engagement in management decision-making. Here we make five key points about the role of insect science in aiding and crafting management decisions, and we illustrate those points with the monarch butterfly and the Karner blue butterfly, two species undergoing considerable change and facing new management dilemmas. Insect biology has a strong history of engagement in applied problems, and as the impacts of climate change increase, a reimagined ethic of entomology in service of broader society may emerge. We hope to motivate insect biologists to contribute time and effort toward solving the challenges of climate change.

  15. Converting pest insects into food

    DEFF Research Database (Denmark)

    Offenberg, Hans Joachim; Wiwatwittaya, Decha

    2010-01-01

    by pest insects, problematic pests are converted into food and additional earnings. To assess the profitability of providing additional food for the ants, O. smaragdina food conversion efficiency (ECI) was estimated in the laboratory. This estimate suggests the feeding of weaver ants in ant farms......Canopy dwelling weaver ants (Oecophylla spp.) are used to control a variety of pests in a number of tropical tree crops. What is less familiar is the existence of commercial markets where these ants and their brood are sold for (i) human consumption, (ii) pet food or (iii) traditional medicine...... on management, 32-115 kg ant brood (mainly new queens) was harvested per ha per year without detrimental effect on colony survival and worker ant densities. This suggest that ant biocontrol and ant harvest can be sustainable integrated in plantations and double benefits derived. As ant production is fuelled...

  16. Energy scavenging from insect flight

    Science.gov (United States)

    Erkan Aktakka, Ethem; Kim, Hanseup; Najafi, Khalil

    2011-09-01

    This paper reports the design, fabrication and testing of an energy scavenger that generates power from the wing motion of a Green June Beetle (Cotinis nitida) during its tethered flight. The generator utilizes non-resonant piezoelectric bimorphs operated in the d31 bending mode to convert mechanical vibrations of a beetle into electrical output. The available deflection, force, and power output from oscillatory movements at different locations on a beetle are measured with a meso-scale piezoelectric beam. This way, the optimum location to scavenge energy is determined, and up to ~115 µW total power is generated from body movements. Two initial generator prototypes were fabricated, mounted on a beetle, and harvested 11.5 and 7.5 µW in device volumes of 11.0 and 5.6 mm3, respectively, from 85 to 100 Hz wing strokes during the beetle's tethered flight. A spiral generator was designed to maximize the power output by employing a compliant structure in a limited area. The necessary technology needed to fabricate this prototype was developed, including a process to machine high-aspect ratio devices from bulk piezoelectric substrates with minimum damage to the material using a femto-second laser. The fabricated lightweight spiral generators produced 18.5-22.5 µW on a bench-top test setup mimicking beetles' wing strokes. Placing two generators (one on each wing) can result in more than 45 µW of power per insect. A direct connection between the generator and the flight muscles of the insect is expected to increase the final power output by one order of magnitude.

  17. Development of insect resistant maize plants expressing a chitinase gene from the cotton leaf worm, Spodoptera littoralis.

    Science.gov (United States)

    Osman, Gamal H; Assem, Shireen K; Alreedy, Rasha M; El-Ghareeb, Doaa K; Basry, Mahmoud A; Rastogi, Anshu; Kalaji, Hazem M

    2015-01-01

    Due to the importance of chitinolytic enzymes for insect, nematode and fungal growth, they are receiving attention concerning their development as biopesticides or chemical defense proteins in transgenic plants and as microbial biocontrol agents. Targeting chitin associated with the extracellular matrices or cell wall by insect chitinases may be an effective approach for controlling pest insects and pathogenic fungi. The ability of chitinases to attack and digest chitin in the peritrophic matrix or exoskeleton raises the possibility to use them as insect control method. In this study, an insect chitinase cDNA from cotton leaf worm (Spodoptera littoralis) has been synthesized. Transgenic maize plant system was used to improve its tolerance against insects. Insect chitinase transcripts and proteins were expressed in transgenic maize plants. The functional integrity and expression of chitinase in progenies of the transgenic plants were confirmed by insect bioassays. The bioassays using transgenic corn plants against corn borer (Sesamia cretica) revealed that ~50% of the insects reared on transgenic corn plants died, suggesting that transgenic maize plants have enhanced resistance against S. cretica. PMID:26658494

  18. [Insect antimicrobial peptides: structures, properties and gene regulation].

    Science.gov (United States)

    Wang, Yi-Peng; Lai, Ren

    2010-02-01

    Insect antimicrobial peptides (AMPs) are an important group of insect innate immunity effectors. Insect AMPs are cationic and contain less than 100 amino acid residues. According to structure, insect AMPs can be divided into a limited number of families. The diverse antimicrobial spectrum of insect AMPs may indicate different modes of action. Research on the model organism Drosophila indicate that insect AMPs gene regulation involves multiple signaling pathways and a large number of signaling molecules.

  19. Distal-less homeobox genes of insects and spiders: genomic organization, function, regulation and evolution.

    Science.gov (United States)

    Chen, Bin; Piel, William H; Monteiro, Antónia

    2016-06-01

    The Distal-less (Dll) genes are homeodomain transcription factors that are present in most Metazoa and in representatives of all investigated arthropod groups. In Drosophila, the best studied insect, Dll plays an essential role in forming the proximodistal axis of the legs, antennae and analia, and in specifying antennal identity. The initiation of Dll expression in clusters of cells in mid-lateral regions of the Drosophila embryo represents the earliest genetic marker of limbs. Dll genes are involved in the development of the peripheral nervous system and sensitive organs, and they also function as master regulators of black pigmentation in some insect lineages. Here we analyze the complete genomes of six insects, the nematode Caenorhabditis elegans and Homo sapiens, as well as multiple Dll sequences available in databases in order to examine the structure and protein features of these genes. We also review the function, expression, regulation and evolution of arthropod Dll genes with emphasis on insects and spiders. PMID:26898323

  20. Genetic basis of the sterile insect technique

    International Nuclear Information System (INIS)

    The use of the sterile insect technique for insect control relies on the introduction of sterility in the females of the wild population. This sterility is produced following the mating of these females with released males carrying, in their sperm, dominant lethal mutations that have been induced by ionizing radiation. As well as radiation-induced sterility, natural mechanisms can be recruited, especially the use of hybrid sterility. Radiation is usually one of the last procedures that insects undergo before leaving mass-rearing facilities for release in the field. It is essential that the dosimetry of the radiation source be checked to ensure that all the insects receive the required minimum dose. A dose should be chosen that maximizes the level of introduced sterility in the wild females in the field. Irradiation in nitrogen can provide protection against the detrimental somatic effects of radiation. Currently, the development of molecular methods to sterilize pest insects in the field, by the release of fertile insects carrying trans genes, is very much in vogue. It is concluded that using a physical process, such as radiation, will always have significant advantages over genetic and other methods of sterilization for the large-scale application of the sterile insect technique. (author)

  1. Insect prophenoloxidase: the view beyond immunity

    Directory of Open Access Journals (Sweden)

    Anrui eLu

    2014-07-01

    Full Text Available Insect prophenoloxidase (PPO is an important innate immunity protein due to its involvement in cellular and humoral defense. It belongs to a group of type-3 copper-containing proteins that occurs in almost all organisms. Insect PPO has been studied for over a century, and the PPO activation cascade is becoming clearer. The insect PPO activation pathway incorporates several important proteins, including pattern-recognition receptors (PGRP, βGRP and C-type lectins, serine proteases, and serine protease inhibitors (serpins. Due to their complexity, PPO activation mechanisms vary among insect species. Activated phenoloxidase (PO oxidizes phenolic molecules to produce melanin around invading pathogens and wounds. The crystal structure of Manduca sexta PPO shows that a conserved amino acid, phenylalanine (F, can block the active site pocket. During activation, this blocker must be dislodged or even cleaved at the N-terminal sequence to expose the active site pockets and allow substrates to enter. Thanks to the crystal structure of M. sexta PPO, some domains and specific amino acids that affect PPO activities have been identified. Further studies of the relationship between PPO structure and enzyme activities will provide an opportunity to examine other type-3 copper proteins, and trace when and why their various physiological functions evolved. Recent researches show that insect PPO has a relationship with neuron activity, longevity, feces melanization (phytophagous insects and development, which suggests that it is time for us to look back on insect PPO beyond the view of immunity in this review.

  2. Forests and climate change - lessons from insects

    Directory of Open Access Journals (Sweden)

    Battisti A

    2004-01-01

    Full Text Available The climate change may indirectly affects the forest ecosystems through the activity of phytophagous insects. The climate change has been claimed to be responsible of the range expansion northward and upward of several insect species of northern temperate forests, as well as of changes in the seasonal phenology. Several papers have dealt with the prediction of the most likely consequences of the climate change on the phytophagous insects, including some of the most important forest pests. Increased levels of CO2 in the atmosphere involve an increase of the C/N balance of the plant tissues, which in turn results in a lower food quality for many defoliating insects. Some insects respond by increasing the level of leaf consumption and consequently the damage to the tree, whereas others show higher mortality and lower performance. The level of plant chemical defenses may also be affected by a change of CO2. The temperature is affecting either the survival of the insects which are active during the cold period, such as the pine processionary moth, or the synchronization mechanism between the host and the herbivores, as in the case of the larch bud moth. An increase of temperature may alter the mechanism by which the insects adjust their cycles to the local climate (diapause, resulting in faster development and higher feeding rate, as in the case of the spruce webspinning sawfly outbreaks in the Southern Alps.

  3. Forests and climate change - lessons from insects

    Directory of Open Access Journals (Sweden)

    Battisti A

    2008-02-01

    Full Text Available The climate change may indirectly affects the forest ecosystems through the activity of phytophagous insects. The climate change has been claimed to be responsible of the range expansion northward and upward of several insect species of northern temperate forests, as well as of changes in the seasonal phenology. Several papers have dealt with the prediction of the most likely consequences of the climate change on the phytophagous insects, including some of the most important forest pests. Increased levels of CO2 in the atmosphere involve an increase of the C/N balance of the plant tissues, which in turn results in a lower food quality for many defoliating insects. Some insects respond by increasing the level of leaf consumption and consequently the damage to the tree, whereas others show higher mortality and lower performance. The level of plant chemical defences may also be affected by a change of CO2. The temperature is affecting either the survival of the insects which are active during the cold period, such as the pine processionary moth, or the synchronization mechanism between the host and the herbivores, as in the case of the larch bud moth. An increase of temperature may alter the mechanism by which the insects adjust their cycles to the local climate (diapause, resulting in faster development and higher feeding rate, as in the case of the spruce web-spinning sawfly outbreaks in the Southern Alps.

  4. Modern Stored-Product Insect Pest Management

    Directory of Open Access Journals (Sweden)

    Hagstrum David William

    2014-07-01

    Full Text Available Stored-product entomologists have a variety of new monitoring, decision-making, biological, chemical, and physical pest management tools available to them. Two types of stored-product insect populations are of interest: insects of immediate economic importance infesting commodities, and insects that live in food residues in equipment and facilities. The sampling and control methods change as grain and grain products move from field to consumer. There are also some changes in the major insect pest species to take into consideration. In this review, we list the primary insect pests at each point of the marketing system, and indicate which sampling methods and control strategies are most appropriate. Economic thresholds for insect infestation levels developed for raw commodity storage, processing plants, and retail business allow sampling-based pest management to be done before insect infestations cause economic injury. Taking enough samples to have a representative sample (20-30 samples will generally provide enough information to classify a population as above or below an economic threshold.

  5. Resilience in social insect infrastructure systems.

    Science.gov (United States)

    Middleton, Eliza J T; Latty, Tanya

    2016-03-01

    Both human and insect societies depend on complex and highly coordinated infrastructure systems, such as communication networks, supply chains and transportation networks. Like human-designed infrastructure systems, those of social insects are regularly subject to disruptions such as natural disasters, blockages or breaks in the transportation network, fluctuations in supply and/or demand, outbreaks of disease and loss of individuals. Unlike human-designed systems, there is no deliberate planning or centralized control system; rather, individual insects make simple decisions based on local information. How do these highly decentralized, leaderless systems deal with disruption? What factors make a social insect system resilient, and which factors lead to its collapse? In this review, we bring together literature on resilience in three key social insect infrastructure systems: transportation networks, supply chains and communication networks. We describe how systems differentially invest in three pathways to resilience: resistance, redirection or reconstruction. We suggest that investment in particular resistance pathways is related to the severity and frequency of disturbance. In the final section, we lay out a prospectus for future research. Human infrastructure networks are rapidly becoming decentralized and interconnected; indeed, more like social insect infrastructures. Human infrastructure management might therefore learn from social insect researchers, who can in turn make use of the mature analytical and simulation tools developed for the study of human infrastructure resilience. PMID:26962030

  6. Prostaglandins and their receptors in insect biology

    Directory of Open Access Journals (Sweden)

    David eStanley

    2011-12-01

    Full Text Available We treat the biological significance of prostaglandins (PGs and their known receptors in insect biology. PGs and related eicosanoids are oxygenated derivatives of arachidonic acid (AA and two other C20 polyunsaturated fatty acids. PGs are mostly appreciated in the context of biomedicine, but a growing body of literature indicates the biological significance of these compounds extends throughout the animal kingdom, and possibly beyond. PGs act in several crucial areas of insect biology. In reproduction, a specific PG, PGE2, releases oviposition behavior in most crickets and a few other insect species; PGs also mediate events in egg development in some species, which may represent all insects. PGs play major roles in modulating fluid secretion in Malpighian tubules, rectum and salivary glands, although, again, this has been studied in only a few insect species that may represent the Class. Insect immunity is a very complex defense system. PGs and other eicosanoids mediate a large number of immune reactions to infection and invasion. The actions of most PGs are mediated by specific receptors. Biomedical research has discovered a great deal of knowledge about PG receptors in mammals, including their structures, pharmacology, molecular biology and cellular locations. Studies of PG receptors in insects lag behind the biomedical background, however, recent results hold the promise of accelerated research in this area. A PG receptor has been identified in a class of lepidopteran hemocytes and experimentally linked to the release of prophenoloxidase. We conclude that research into PGs and their receptors in insects will lead to important advances in our understanding of insect biology.

  7. An Automated Flying-Insect Detection System

    Science.gov (United States)

    Vann, Timi; Andrews, Jane C.; Howell, Dane; Ryan, Robert

    2007-01-01

    An automated flying-insect detection system (AFIDS) was developed as a proof-of-concept instrument for real-time detection and identification of flying insects. This type of system has use in public health and homeland-security decision support, agriculture and military pest management, and/or entomological research. Insects are first lured into the AFIDS integrated sphere by insect attractants. Once inside the sphere, the insect s wing beats cause alterations in light intensity that is detected by a photoelectric sensor. Following detection, the insects are encouraged (with the use of a small fan) to move out of the sphere and into a designated insect trap where they are held for taxonomic identification or serological testing. The acquired electronic wing-beat signatures are preprocessed (Fourier transformed) in real time to display a periodic signal. These signals are sent to the end user where they are graphically. All AFIDS data are preprocessed in the field with the use of a laptop computer equipped with LabVIEW. The AFIDS software can be programmed to run continuously or at specific time intervals when insects are prevalent. A special DC-restored transimpedance amplifier reduces the contributions of low-frequency background light signals, and affords approximately two orders of magnitude greater AC gain than conventional amplifiers. This greatly increases the signal-to-noise ratio and enables the detection of small changes in light intensity. The AFIDS light source consists of high-intensity Al-GaInP light-emitting diodes (LEDs). The AFIDS circuitry minimizes brightness fluctuations in the LEDs and when integrated with an integrating sphere, creates a diffuse uniform light field. The insect wing beats isotropically scatter the diffuse light in the sphere and create wing-beat signatures that are detected by the sensor. This configuration minimizes variations in signal associated with insect flight orientation. Preliminary data indicate that AFIDS has

  8. Expression of the movement protein of tomato spotted wilt virus in the insect vector Frankliniella occidentalis.

    NARCIS (Netherlands)

    Storms, M.; Nagata, T.; Kormelink, R.; Lent, van J.W.M.; Goldbach, R.W.

    2002-01-01

    Tomato spotted wilt virus (TSWV) is able to infect both its botanical hosts and its insect vector (thrips). In plant tissue the NSM protein of TSWV functions as viral movement protein (MP), aggregating into plasmodesma-penetrating tubules to establish cell-to-cell movement. As upon heterologous expr

  9. Differential scaling within an insect compound eye.

    Science.gov (United States)

    Perl, Craig D; Niven, Jeremy E

    2016-03-01

    Environmental and genetic influences cause individuals of a species to differ in size. As they do so, organ size and shape are scaled to available resources whilst maintaining function. The scaling of entire organs has been investigated extensively but scaling within organs remains poorly understood. By making use of the structure of the insect compound eye, we show that different regions of an organ can respond differentially to changes in body size. Wood ant (Formica rufa) compound eyes contain facets of different diameters in different regions. When the animal body size changes, lens diameters from different regions can increase or decrease in size either at the same rate (a 'grade' shift) or at different rates (a 'slope' shift). These options are not mutually exclusive, and we demonstrate that both types of scaling apply to different regions of the same eye. This demonstrates that different regions within a single organ can use different rules to govern their scaling, responding differently to their developmental environment. Thus, the control of scaling is more nuanced than previously appreciated, diverse responses occurring even among homologous cells within a single organ. Such fine control provides a rich substrate for the diversification of organ morphology. PMID:26979561

  10. TRANSGENIC PLANTS RESISTANT TO INSECTS

    Directory of Open Access Journals (Sweden)

    S. Kereša

    2009-09-01

    Full Text Available Proteinase inhibitors are secondary metabolites present in all plants and it seems that their major role is protection of plants against attacks of animals, insects and microorganisms. One of the family of proteinase inhibitors are squash inhibitors of serine proteinases purified from seeds belonging to genera Cucurbita, Cucumis and Momordica. Squash inhibitors consist of 29-32 amino acid residues and are considered to be the smallest inhibitors of the serine proteinases known. Because of shortness, genes for these inhibitors could be synthesised and modified at different ways. Modifications could lead to changes in inhibitor activity. Tobacco as a model plant was transformed with 12 different genes of squash inhibitors. Stable integration of transgenes in putative transgenic plants was determined by PCR analysis using genomic DNA and primers that anneal to promoter and terminator region. The first step of proteinase inhibitor gene expression in transgenic plants was revealed by RT-PCR analysis. In entomological tests where larvae were fed with leaves, influence of transgenic T0 plants, as well as non-transgenic control plants on retardation of larval growth of S. littoralis was examined. Results of entomological tests showed that it is possible to express squash proteinase inhibitors in plants at level that significantly reduces S. littoralis larval growth.

  11. Discovery of insect and human dengue virus host factors.

    Science.gov (United States)

    Sessions, October M; Barrows, Nicholas J; Souza-Neto, Jayme A; Robinson, Timothy J; Hershey, Christine L; Rodgers, Mary A; Ramirez, Jose L; Dimopoulos, George; Yang, Priscilla L; Pearson, James L; Garcia-Blanco, Mariano A

    2009-04-23

    Dengue fever is the most frequent arthropod-borne viral disease of humans, with almost half of the world's population at risk of infection. The high prevalence, lack of an effective vaccine, and absence of specific treatment conspire to make dengue fever a global public health threat. Given their compact genomes, dengue viruses (DENV-1-4) and other flaviviruses probably require an extensive number of host factors; however, only a limited number of human, and an even smaller number of insect host factors, have been identified. Here we identify insect host factors required for DENV-2 propagation, by carrying out a genome-wide RNA interference screen in Drosophila melanogaster cells using a well-established 22,632 double-stranded RNA library. This screen identified 116 candidate dengue virus host factors (DVHFs). Although some were previously associated with flaviviruses (for example, V-ATPases and alpha-glucosidases), most of the DVHFs were newly implicated in dengue virus propagation. The dipteran DVHFs had 82 readily recognizable human homologues and, using a targeted short-interfering-RNA screen, we showed that 42 of these are human DVHFs. This indicates notable conservation of required factors between dipteran and human hosts. This work suggests new approaches to control infection in the insect vector and the mammalian host.

  12. A new family of insect muscarinic acetylcholine receptors.

    Science.gov (United States)

    Xia, R-Y; Li, M-Q; Wu, Y-S; Qi, Y-X; Ye, G-Y; Huang, J

    2016-08-01

    Most currently used insecticides are neurotoxic chemicals that target a limited number of sites and insect cholinergic neurotransmission is the major target. A potential target for insecticide development is the muscarinic acetylcholine receptor (mAChR), which is a metabotropic G-protein-coupled receptor. Insects have A- and B-type mAChRs and the five mammalian mAChRs are close to the A-type. We isolated a cDNA (CG12796) from the fruit fly, Drosophila melanogaster. After heterologous expression in Chinese hamster ovary K1 cells, CG12796 could be activated by acetylcholine [EC50 (half maximal effective concentration), 73 nM] and the mAChR agonist oxotremorine M (EC50 , 48.2 nM) to increase intracellular Ca(2+) levels. Thus, the new mAChR is coupled to Gq/11 but not Gs and Gi/o . The classical mAChR antagonists atropine and scopolamine N-butylbromide at 100 μM completely blocked the acetylcholine-induced responses. The orthologues of CG12796 can also be found in the genomes of other insects, but not in the genomes of the honeybee or parasitoid wasps. Knockdown of CG12796 in the central nervous system had no effect on male courtship behaviours. We suggest that CG12796 represents the first recognized member of a novel mAChR class. PMID:27003873

  13. The centriole adjunct of insects: Need to update the definition.

    Science.gov (United States)

    Dallai, Romano; Paoli, Francesco; Mercati, David; Lupetti, Pietro

    2016-04-01

    The ancestral eukaryotes presumably had an MTOC (microtubule organizing center) which late gave origin to the centriole and the flagellar axoneme. The centrosome of insect early spermatids is in general composed of two components: a single centriole and a cloud of electron-dense pericentriolar material (PCM). During spermiogenesis, the centriole changes its structure and gives rise to a flagellar axoneme, while the proteins of PCM, gamma tubulin in particular, are involved in the production of microtubules for the elongation and shaping of spermatid components. At the end of spermiogenesis, in many insects, additional material is deposited beneath the nucleus to form the centriole adjunct (ca). This material can also extend along the flagellum in two accessory bodies (ab) flanking the axoneme. Among Homoptera Sternorrhyncha, a progressive modification of their sperm flagella until complete disappearance has been verified. In the Archaeococcidae Matsucoccus feytaudi, however, a motile sperm flagellum-like structure is formed by an MTOC activity. This finding gives support to the hypothesis that an evolutionary reversal has occurred in the group and that the cell, when a non-functional centriole is present, activates an ancestral structure, an MTOC, to form a polarized motile bundle of microtubules restoring sperm motility. The presence and extension of the centriole adjunct in the different insect orders is also enlisted. PMID:26899558

  14. Cathepsins of lepidopteran insects: Aspects and prospects.

    Science.gov (United States)

    Saikhedkar, Nidhi; Summanwar, Aarohi; Joshi, Rakesh; Giri, Ashok

    2015-09-01

    Molecular understanding of lepidopteran physiology has revealed that proteases consist of one of the central regulatory/reacting system for insect growth and survival. Among the various proteases, cathepsins are the most crucial cellular proteases, which play vital roles during insect development. In the present review, we have discussed various aspects of the lepidopteran insect cathepsins, emphasizing their roles in processes like development, growth, metamorphosis, apoptosis and immunity. Cathepsins are categorized into different types on the basis of their sequence diversification, leading to variation in structure and catalytic function. Cathepsins exhibit tissue and stage specific expression pattern which is fine-tuned by a delicate balance of expression, compartmentalization, zymogen activation, inhibition by protein inhibitors and degradation. The indispensability of cathepsins as cellular proteases in the above mentioned processes proposes them as novel targets for designing effective and specific insect controlling strategies.

  15. The Evolution of Agriculture in Insects

    DEFF Research Database (Denmark)

    Mueller, Ulrich G.; Gerardo, Nicole M.; Aanen, Duur Kornelis;

    2005-01-01

    Agriculture has evolved independently in three insect orders: once in ants, once in termites, and seven times in ambrosia beetles. Although these insect farmers are in some ways quite different from each other, in many more ways they are remarkably similar, suggesting convergent evolution. All...... propagate their cultivars as clonal monocultures within their nests and, in most cases, clonally across many farmer generations as well. Long-term clonal monoculture presents special problems for disease control, but insect farmers have evolved a combination of strategies to manage crop diseases: They (a......, in addition to the primary cultivars, an array of "auxiliary" microbes providing disease suppression and other services. Rather than growing a single cultivar solely for nutrition, insect farmers appear to cultivate, and possibly "artificially select" for, integrated crop-microbe consortia. Indeed, crop...

  16. Middle-scale navigation: the insect case

    OpenAIRE

    Wehner, R

    1996-01-01

    What is the large-scale spatial representation that insect foragers such as bees and ants form of their wider nest environs? This is the principal question which the following contributions aim to answer.

  17. Insect food aiming at Mars emigration

    Science.gov (United States)

    Katayama, Naomi; Yamashita, Masamichi; Hashimoto, Hirofumi; Nagasaka, Sanako; Kuwayama, Akemi; Sofue, Megumi

    2012-07-01

    We study insect food aiming at Mars emigration.In space agriculture, insect is the important creature which we cannot miss.It is necessary for the pollination of the plant, and it is rich to protein and lipid as food.I reported that silkworm is an insect necessary for astroponics in particular last time.We make clothes using silk thread, and the pupa becomes the food.In addition, the clothes can make food as protein when we need not to use it. The bee is a very important insect in the space agriculture,too.We examined nutrition of silkworm, bee, grasshopper, snail and the white ant which are necessary for Mars emigration.We will introduce of good balance space foods.We will report many meal menu for Mars emigration.

  18. Insect trypanosomatids: the need to know more

    Directory of Open Access Journals (Sweden)

    Sergei A Podlipaev

    2000-08-01

    Full Text Available Of ten recognized trypanosomatid genera, only two -- pathogenic Trypanosoma and Leishmania -- have been actively investigated for any length of time while the plant flagellates -- Phytomonas -- have recently begun to attract attention due to their role as agricultural parasites. The remaining genera that comprise parasites associated with insects have been largely neglected except for two or three containing popular isolates. This publication reviews current knowledge of trypanosomatids from insects.

  19. Minor lipophilic compounds in edible insects

    OpenAIRE

    Monika Sabolová; Anna Adámková; Lenka Kouřimská; Diana Chrpová; Jan Pánek

    2016-01-01

    Contemporary society is faced with the question how to ensure suffiecient nutrition (quantity and quality) for rapidly growing population. One solution can be consumption of edible insect, which can have very good nutritional value (dietary energy, protein, fatty acids, fibers, dietary minerals and vitamins composition). Some edible insects species, which contains a relatively large amount of fat, can have a potential to be a „good" (interesting, new) source of minor lipophilic compound...

  20. Immune response inhibits associative learning in insects.

    OpenAIRE

    Mallon, Eamonn B.; Brockmann, Axel; Schmid-Hempel, Paul

    2003-01-01

    In vertebrates, it is well established that there are many intricate interactions between the immune system and the nervous system, and vice versa. Regarding insects, until now little has been known about the link between these two systems. Here, we present behavioural evidence indicating a link between the immune system and the nervous system in insects. We show that otherwise non-infected honeybees whose immune systems are challenged by a non-pathogenic immunogenic elicitor lipopolysacchari...

  1. Insects as a Nitrogen Source for Plants

    OpenAIRE

    Bidochka, Michael J.; Behie, Scott W.

    2013-01-01

    Many plants have evolved adaptations in order to survive in low nitrogen environments. One of the best-known adaptations is that of plant symbiosis with nitrogen-fixing bacteria; this is the major route by which nitrogen is incorporated into plant biomass. A portion of this plant-associated nitrogen is then lost to insects through herbivory, and insects represent a nitrogen reservoir that is generally overlooked in nitrogen cycles. In this review we show three specialized plant adaptations th...

  2. Potential applications of insect symbionts in biotechnology

    OpenAIRE

    Berasategui, A.; Shukla, S; Salem, H; Kaltenpoth, M.

    2015-01-01

    Symbiotic interactions between insects and microorganisms are widespread in nature and are often the source of ecological innovations. In addition to supplementing their host with essential nutrients, microbial symbionts can produce enzymes that help degrade their food source as well as small molecules that defend against pathogens, parasites, and predators. As such, the study of insect ecology and symbiosis represents an important source of chemical compounds and enzymes with potential biote...

  3. Synthesis of model compounds derived from natural clerodane insect antifeedants

    NARCIS (Netherlands)

    Klein Gebbinck, E.A.

    1999-01-01

    Insect antifeedants are compounds with the ability to reduce or inhibit insect feeding without directly killing the insect. Such compounds offer a number of properties that are highly desirable in environmentally friendly crop protection agents. Although the principle of insect control using antifee

  4. Genetics and Biochemistry of Insect Resistance in Maize

    Science.gov (United States)

    Insects are a major concern for maize production worldwide. Host plant resistance to insects involves a number of chemical and biochemical factors that limit but rarely eliminate insect damage. Most chemical and many biochemical factors involved in resistance to insects are synthesized independent...

  5. Insect-specific flaviviruses, a worldwide widespread group of viruses only detected in insects.

    Science.gov (United States)

    Calzolari, Mattia; Zé-Zé, Líbia; Vázquez, Ana; Sánchez Seco, Mari Paz; Amaro, Fátima; Dottori, Michele

    2016-06-01

    Several flaviviruses are important pathogens for humans and animals (Dengue viruses, Japanese encephalitis virus, Yellow-fever virus, Tick-borne encephalitis virus, West Nile virus). In recent years, numerous novel and related flaviviruses without known pathogenic capacity have been isolated worldwide in the natural mosquito population. However, phylogenetic studies have shown that genomic sequences of these viruses diverge from other flaviviruses. Moreover, these viruses seem to be exclusive of insects (they do not seem to grow on vertebrate cell lines), and were already defined as mosquito-only flaviviruses or insect-specific flaviviruses. At least eleven of these viruses were isolated worldwide, and sequences ascribable to other eleven putative viruses were detected in several mosquito species. A large part of the cycle of these viruses is not well known, and their persistence in the environment is poorly understood. These viruses are detected in a wide variety of distinct mosquito species and also in sandflies and chironomids worldwide; a single virus, or the genetic material ascribable to a virus, was detected in several mosquito species in different countries, often in different continents. Furthermore, some of these viruses are carried by invasive mosquitoes, and do not seem to have a depressive action on their fitness. The global distribution and the continuous detection of new viruses in this group point out the likely underestimation of their number, and raise interesting issues about their possible interactions with the pathogenic flaviviruses, and their influence on the bionomics of arthropod hosts. Some enigmatic features, as their integration in the mosquito genome, the recognition of their genetic material in DNA forms in field-collected mosquitoes, or the detection of the same virus in both mosquitoes and sandflies, indicate that the cycle of these viruses has unknown characteristics that could be of use to reach a deeper understanding of the cycle

  6. Linking energetics and overwintering in temperate insects.

    Science.gov (United States)

    Sinclair, Brent J

    2015-12-01

    Overwintering insects cannot feed, and energy they take into winter must therefore fuel energy demands during autumn, overwintering, warm periods prior to resumption of development in spring, and subsequent activity. Insects primarily consume lipids during winter, but may also use carbohydrate and proteins as fuel. Because they are ectotherms, the metabolic rate of insects is temperature-dependent, and the curvilinear nature of the metabolic rate-temperature relationship means that warm temperatures are disproportionately important to overwinter energy use. This energy use may be reduced physiologically, by reducing the slope or elevation of the metabolic rate-temperature relationship, or because of threshold changes, such as metabolic suppression upon freezing. Insects may also choose microhabitats or life history stages that reduce the impact of overwinter energy drain. There is considerable capacity for overwinter energy drain to affect insect survival and performance both directly (via starvation) or indirectly (for example, through a trade-off with cryoprotection), but this has not been well-explored. Likewise, the impact of overwinter energy drain on growing-season performance is not well understood. I conclude that overwinter energetics provides a useful lens through which to link physiology and ecology and winter and summer in studies of insect responses to their environment.

  7. Extracellular ice phase transitions in insects.

    Science.gov (United States)

    Hawes, T C

    2014-01-01

    At temperatures below their temperature of crystallization (Tc), the extracellular body fluids of insects undergo a phase transition from liquid to solid. Insects that survive the transition to equilibrium (complete freezing of the body fluids) are designated as freeze tolerant. Although this phenomenon has been reported and described in many Insecta, current nomenclature and theory does not clearly delineate between the process of transition (freezing) and the final solid phase itself (the frozen state). Thus freeze tolerant insects are currently, by convention, described in terms of the temperature at which the crystallization of their body fluids is initiated, Tc. In fact, the correct descriptor for insects that tolerate freezing is the temperature of equilibrium freezing, Tef. The process of freezing is itself a separate physical event with unique physiological stresses that are associated with ice growth. Correspondingly there are a number of insects whose physiological cryo-limits are very specifically delineated by this transitional envelope. The distinction also has considerable significance for our understanding of insect cryobiology: firstly, because the ability to manage endogenous ice growth is a fundamental segregator of cryotype; and secondly, because our understanding of internal ice management is still largely nascent.

  8. Wetting Characteristics of Insect Wing Surfaces

    Institute of Scientific and Technical Information of China (English)

    Doyoung Byun; Jongin Hong; Saputra; Jin Hwan Ko; Young Jong Lee; Hoon Cheol Park; Bong-Kyu Byun; Jennifer R. Lukes

    2009-01-01

    Biological tiny structures have been observed on many kinds of surfaces such as lotus leaves, which have an effect on the coloration of Morpho butterflies and enhance the hydrophobicity of natural surfaces. We investigated the micro-scale and nano-scale structures on the wing surfaces of insects and found that the hierarchical multiple roughness structures help in enhancing the hydrophobicity. After examining 10 orders and 24 species of flying Pterygotan insects, we found that micro-scale and nano-scale structures typically exist on both the upper and lower wing surfaces of flying insects. The tiny structures such as denticle or setae on the insect wings enhance the hydrophobicity, thereby enabling the wings to be cleaned more easily. And the hydrophobic insect wings undergo a transition from Cassie to Wenzel states at pitch/size ratio of about 20. In order to examine the wetting characteristics on a rough surface, a biomimetic surface with micro-scale pillars is fabricated on a silicon wafer,which exhibits the same behavior as the insect wing, with the Cassie-Wenzel transition occurring consistently around a pitch/width value of 20.

  9. Linking energetics and overwintering in temperate insects.

    Science.gov (United States)

    Sinclair, Brent J

    2015-12-01

    Overwintering insects cannot feed, and energy they take into winter must therefore fuel energy demands during autumn, overwintering, warm periods prior to resumption of development in spring, and subsequent activity. Insects primarily consume lipids during winter, but may also use carbohydrate and proteins as fuel. Because they are ectotherms, the metabolic rate of insects is temperature-dependent, and the curvilinear nature of the metabolic rate-temperature relationship means that warm temperatures are disproportionately important to overwinter energy use. This energy use may be reduced physiologically, by reducing the slope or elevation of the metabolic rate-temperature relationship, or because of threshold changes, such as metabolic suppression upon freezing. Insects may also choose microhabitats or life history stages that reduce the impact of overwinter energy drain. There is considerable capacity for overwinter energy drain to affect insect survival and performance both directly (via starvation) or indirectly (for example, through a trade-off with cryoprotection), but this has not been well-explored. Likewise, the impact of overwinter energy drain on growing-season performance is not well understood. I conclude that overwinter energetics provides a useful lens through which to link physiology and ecology and winter and summer in studies of insect responses to their environment. PMID:26615721

  10. International Symposium on Insect Physiology, Biochemistry and Molecular Biology

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ We are building on the success of the Sixth Chinese Insect Physiology, Biochemistry and Molecular Biology Symposium, Beijing, held in 2005. The 2005 symposium saw many Chinese and international authorities share their expertise in a broad range of insect science, including analyses of insect genomes and proteomes, functional gene expression and regulation during development, insect immunity, insect neurobiology, insect-host interactions and insect chemical communication. The coming symposium, which will be held in Shandong University,Jinan, Shandong province, September 19-22, 2007, will offer material along similar lines.

  11. Evolution of the insect desaturase gene family with an emphasis on social Hymenoptera.

    Science.gov (United States)

    Helmkampf, Martin; Cash, Elizabeth; Gadau, Jürgen

    2015-02-01

    Desaturase genes are essential for biological processes, including lipid metabolism, cell signaling, and membrane fluidity regulation. Insect desaturases are particularly interesting for their role in chemical communication, and potential contribution to speciation, symbioses, and sociality. Here, we describe the acyl-CoA desaturase gene families of 15 insects, with a focus on social Hymenoptera. Phylogenetic reconstruction revealed that the insect desaturases represent an ancient gene family characterized by eight subfamilies that differ strongly in their degree of conservation and frequency of gene gain and loss. Analyses of genomic organization showed that five of these subfamilies are represented in a highly microsyntenic region conserved across holometabolous insect taxa, indicating an ancestral expansion during early insect evolution. In three subfamilies, ants exhibit particularly large expansions of genes. Despite these expansions, however, selection analyses showed that desaturase genes in all insect lineages are predominantly undergoing strong purifying selection. Finally, for three expanded subfamilies, we show that ants exhibit variation in gene expression between species, and more importantly, between sexes and castes within species. This suggests functional differentiation of these genes and a role in the regulation of reproductive division of labor in ants. The dynamic pattern of gene gain and loss of acyl-CoA desaturases in ants may reflect changes in response to ecological diversification and an increased demand for chemical signal variability. This may provide an example of how gene family expansions can contribute to lineage-specific adaptations through structural and regulatory changes acting in concert to produce new adaptive phenotypes. PMID:25425561

  12. Climate change will exacerbate California’s insect pest problems

    OpenAIRE

    Trumble, John; Butler, Casey

    2009-01-01

    The elevated carbon dioxide concentrations and increasing temperatures associated with climate change will have substantial impacts on plant-insect interactions, integrated pest management programs and the movement of nonnative insect species into California. Natural ecosystems will also be affected by the expected changes in insect diversity. Many insects will alter how much they eat in response to changing plant nutrition. Also, we can expect increased problems with many pest insects as the...

  13. Applying the sterile insect technique to the control of insect pests

    International Nuclear Information System (INIS)

    The sterile insect technique (SIT) is basically a novel twentieth century approach to insect birth control. It is species specific and exploits the mate seeking behaviour of the insect. The basic principle is simple. Insects are mass reared in 'factories' and sexually sterilized by gamma rays from a 60Co source. The sterile insects are then released in a controlled fashion into nature. Matings between the sterile insects released and native insects produced no progeny. If enough of these matings take place, reproduction of the pest population decreases. With continued release, the pest population can be controlled and in some cases eradicated. In the light of the many important applications of the SIT worldwide and the great potential that SIT concepts hold for insect and pest control in developing countries, two special benefits should be stressed. Of greatest significance is the fact that the SIT permits suppression and eradication of insect pests in an environmentally harmless manner. It combines nuclear techniques with genetic approaches and, in effect, replaces intensive use of chemicals in pest control. Although chemicals are used sparingly at the outset in some SIT programmes to reduce the size of the pest population before releases of sterilized insects are started, the total amount of chemicals used in an SIT programme is a mere fraction of what would be used without the SIT. It is also of great importance that the SIT is not designed strictly for the eradication of pest species but can readily be used in the suppression of insect populations. In fact, the SIT is ideally suited for use in conjunction with other agricultural pest control practices such as the use of parasites and predators, attractants and cultural controls (e.g. ploughing under or destruction of crop residues) in integrated pest management programmes to achieve control at the lowest possible price and with a minimum of chemical contamination of the environment

  14. Molecular identification of the first insect proctolin receptor

    DEFF Research Database (Denmark)

    Egerod, Kristoffer; Reynisson, Eyjólfur; Hauser, Frank;

    2003-01-01

    The website of the Drosophila Genome Project (www.flybase.org) contains the sequence of an annotated gene CG6986, which is predicted to code for a G protein-coupled receptor. We cloned the cDNA of this gene and expressed it in Chinese hamster ovary cells. Screening of a neuropeptide library revea...... revealed that the expressed receptor was specific for the neuropeptide proctolin (EC(50), 6x10(-10)M). Proctolin (RYLPT) was the first invertebrate neuropeptide to be fully sequenced (already in 1975) and occurs with identical structure in both crustaceans and insects, where it has myo...

  15. Agricultural production - Phase 2. Indonesia. Insect ecology studies and insect pest control

    International Nuclear Information System (INIS)

    This document reviews the activities of the Pest Control Research Group in Indonesia. Pests under study are the diamondback moth (Plutella xylostella), the rice stem borer (Chilo suppressalis), the sugar cane borer (Chilo auricilius), bean flies (Agromyza spp.), tobacco insects (Heliothis armigera and Spodoptera litura) and cotton insects, especially the pink bollworm

  16. 昆虫细胞(Sf21)悬浮培养过程中生长限制性基质 间歇补加技术的应用%Application of Intermittent-feeding of Growth-limiting Nutrients in Suspension Culture of Insect Cells(Sf21)

    Institute of Scientific and Technical Information of China (English)

    赵佼; 谭文松; 周燕; 周利; 俞俊棠

    2000-01-01

    On the basis of the growth and metabolism behavior inherent in suspended Sf21 insect cells,the intermittent feeding of growth-limiting nutrients(glucose and protein hydrolysates)was employed in the regulation of cellular growth during the cultivation by using the residual glucose concentration as a reference point. It was shown that as compared with the batch cultivation, the intermittent-feeding of growth-limiting nutrients effectively prolonged the growth and stationary phase for Sf21 insect cells grown in two representative culture medium(TC-100 and IPL-41). The maximum cell density was increased from 3.0×106 cells/ml to 6.5×106 cells/mL in TC-100 medium, and in IPL-41 medium, the maximum cell density was increased from 7.05×106 cells/mL to 9.0×106 cells/mL. As the defined nutrient solution was used for feeding in lieu of the complicated and expensive base medium, the technique would find prospects in large scale high-density cultivation of insect cells.%基于Sf21昆虫细胞在悬浮培养过程中所表现出的生长代谢特征,提出以培养液中残糖浓度作为控制参数,并利用限制性基质(葡萄糖和蛋白水解物)的间歇补加技术调控细胞生长的方案。实际控制表明:与批培养相比,Sf21细胞在两种具代表性的昆虫细胞培养基(IPL-41和TC-100)中的生长期和稳定期都得到了有效的延长。TC-100培养液中最高细胞培养密度由3.0×106 cells/mL提高到6.5×106 cells/mL;IPL-41培养液中最高细胞培养密度则由7.05×106 cells/mL提高到9.0×106cells/mL。由于限制性基质的间歇补加技术是利用较确定的营养成分来代替复杂昂贵的补料培养基,因此更适合于昆虫细胞的大规模高密度培养。

  17. Biological basis of the sterile insect technique

    International Nuclear Information System (INIS)

    In principle, the sterile insect technique (SIT) is applicable to controlling a wide variety of insect pests, but biological factors, interacting with socio-economic and political forces, restrict its practical use to a narrower set of pest species and situations. This chapter reviews how the biology and ecology of a given pest affect the feasibility and logistics of developing and using the SIT against that pest insect. The subjects of pest abundance, distribution, and population dynamics are discussed in relation to producing and delivering sufficient sterile insects to control target populations. Pest movement and distribution are considered as factors that influence the feasibility and design of SIT projects, including the need for population- or area-wide management approaches. Biological characteristics, that affect the ability of sterile insects to interact with wild populations, are presented, including the nature of mating systems of pests, behavioural and physiological consequences of mass production and sterilization, and mechanisms that males use to block a female's acquisition and/or use of sperm from other males. An adequate knowledge of the biology of the pest species and potential target populations is needed, both for making sound decisions on whether integration of the SIT into an area-wide integrated pest management (AW-IPM) programme is appropriate, and for the efficient and effective application of the technique. (author)

  18. Recombinant DNA technology and insect control

    International Nuclear Information System (INIS)

    In the past, the most successful avenue for the use of genetics in insect control has been the employment of the sterile insect technique, in which huge numbers of a species are produced in a factory, sterilized by exposure to ionizing radiation and released into the native habitat. this method is suitable for some species, but for logistical, economical, and biological reasons this control technique is not suitable for many economically important species. Our ability to use genetic approaches to cope with the myriad of insect pests will improve in the near future because of progress in the biochemical manipulation of genes. Molecular geneticists have created bacteria, plants, animals, and fungi that have useful new properties, and many of these are being used or tested for commercial use. A reasonable forecast is that a virtual revolution will occur in the way that we currently practice and perceive the genetic control of insects. Using genetic engineering manipulations to develop control techniques for insects of agricultural and public health importance is an exciting prospect and a highly desirable goal

  19. Veins improve fracture toughness of insect wings.

    Directory of Open Access Journals (Sweden)

    Jan-Henning Dirks

    Full Text Available During the lifetime of a flying insect, its wings are subjected to mechanical forces and deformations for millions of cycles. Defects in the micrometre thin membranes or veins may reduce the insect's flight performance. How do insects prevent crack related material failure in their wings and what role does the characteristic vein pattern play? Fracture toughness is a parameter, which characterises a material's resistance to crack propagation. Our results show that, compared to other body parts, the hind wing membrane of the migratory locust S. gregaria itself is not exceptionally tough (1.04±0.25 MPa√m. However, the cross veins increase the wing's toughness by 50% by acting as barriers to crack propagation. Using fracture mechanics, we show that the morphological spacing of most wing veins matches the critical crack length of the material (1132 µm. This finding directly demonstrates how the biomechanical properties and the morphology of locust wings are functionally correlated in locusts, providing a mechanically 'optimal' solution with high toughness and low weight. The vein pattern found in insect wings thus might inspire the design of more durable and lightweight artificial 'venous' wings for micro-air-vehicles. Using the vein spacing as indicator, our approach might also provide a basis to estimate the wing properties of endangered or extinct insect species.

  20. Uncontrolled Stability in Freely Flying Insects

    Science.gov (United States)

    Melfi, James, Jr.; Wang, Z. Jane

    2015-11-01

    One of the key flight modes of a flying insect is longitudinal flight, traveling along a localized two-dimensional plane from one location to another. Past work on this topic has shown that flying insects, unless stabilized by some external stimulus, are typically unstable to a well studied pitching instability. In our work, we examine this instability in a computational study to understand whether it is possible for either evolution or an aero-vehicle designer to stabilize longitudinal flight through changes to insect morphology, kinematics, or aerodynamic quantities. A quasi-steady wingbeat averaged flapping flight model is used to describe the insect. From this model, a number of non-dimensional parameters are identified. The effect of these parameters was then quantified using linear stability analysis, applied to various translational states of the insect. Based on our understanding of these parameters, we demonstrate how to find an intrinsically stable flapping flight sequence for a dragonfly-like flapping flier in an instantaneous flapping flight model.

  1. Acoustic communication in insect disease vectors

    Directory of Open Access Journals (Sweden)

    Felipe de Mello Vigoder

    2013-01-01

    Full Text Available Acoustic signalling has been extensively studied in insect species, which has led to a better understanding of sexual communication, sexual selection and modes of speciation. The significance of acoustic signals for a blood-sucking insect was first reported in the XIX century by Christopher Johnston, studying the hearing organs of mosquitoes, but has received relatively little attention in other disease vectors until recently. Acoustic signals are often associated with mating behaviour and sexual selection and changes in signalling can lead to rapid evolutionary divergence and may ultimately contribute to the process of speciation. Songs can also have implications for the success of novel methods of disease control such as determining the mating competitiveness of modified insects used for mass-release control programs. Species-specific sound “signatures” may help identify incipient species within species complexes that may be of epidemiological significance, e.g. of higher vectorial capacity, thereby enabling the application of more focussed control measures to optimise the reduction of pathogen transmission. Although the study of acoustic communication in insect vectors has been relatively limited, this review of research demonstrates their value as models for understanding both the functional and evolutionary significance of acoustic communication in insects.

  2. Insect pest management in forest ecosystems

    Science.gov (United States)

    Dahlsten, Donald L.; Rowney, David L.

    1983-01-01

    Understanding the role of insects in forest ecosystems is vital to the development of environmentally and economically sound pest management strategies in forestry Most of the research on forest insects has been confined to phytophagous species associated with economically important tree species The roles of most other insects in forest environments have generally been ignored, including the natural enemies and associates of phytophagous species identified as being important In the past few years several investigations have begun to reevaluate the role of phytophagous species responsible for perturbation in forest ecosystems, and it appears that these species may be playing an important role in the primary productivity of those ecosystems Also, there is an increasing awareness that forest pest managers have been treating the symptoms and not the causes of the problems in the forest Many insect problems are associated with poor sites or sites where trees are growing poorly because of crowding As a result, there is considerable emphasis on the hazard rating of stands of trees for their susceptibility to various phytophagous insects The next step is to manipulate forest stands to make them less susceptible to forest pest complexes A thinning study in California is used as an example and shows that tree mortality in ponderosa pine ( Pinus ponderosa) attributable to the western pine beetle ( Dendroctonus brevicomis) can be reduced by commercial thinning to reduce stocking

  3. 蝙蝠SARS样冠状病毒S蛋白受体结合域在昆虫细胞中的表达和纯化%Expression and purification of receptor binding domain of bat SARS-like coronavirus spike proteins in insect cells

    Institute of Scientific and Technical Information of China (English)

    谢天炽; 肖洪广; 林勇平; 高俊

    2011-01-01

    Objective:To express the receptor binding domain ( RBD) of bat SARS-like coronavirus spike proteins in the expression system of insect cells, and to explore its dynamics of expression and purification conditions. Methods Gene amplification of RBD located in the spike gene of bat SARS-like coronavirus was completed with PCR. The PCR products were connected to the pMD-T vector, which was then subcloned into pFastBacHTB donor plasmid. After confirmed by DNA sequencing, the recombinant plasmid was further transferred into Bacmid and expressed in insect Sf9 cell line. The proteins products of recombinant gene expression were analyzed by using SDS-PAGE and Western blotting, then purified with the nickel chelating resins. Results: The receptor binding domain of bat SARS-like coronavirus spike protein was expressed in the expression system of insect cells,at 56 hours after infection with recombinant virus at a multiplicity of infection 2, the peak expression of the recombinant protein was obtained. Conclusion; The receptor binding domain of bat SARS-like coronavirus spike protein may could be effectively expressed in insect cell expression system,and the recombinant proteins may be purified using nickel chelating resins.%目的:在昆虫细胞表达系统中表达蝙蝠SARS样冠状病毒Spike蛋白的受体结合域,并探讨其表达动力学和纯化条件.方法:以PCR扩增蝙蝠SARS样冠状病毒Spike基因的受体结合域片段,产物连接到pMD-T载体,再亚克隆至供体质粒pFAST-HTB,经序列测定确认基因正确克隆,进一步将其转座入Bacmid中,在昆虫细胞Sf9中进行表达,采用SDS-PAGE和Western blotting对表达产物进行分析,并通过镍离子螯合树脂纯化重组蛋白.结果:在昆虫细胞表达系统中表达出蝙蝠SARS样冠状病毒Spike蛋白的受体结合城片段,当感染复数( multiplicity of infectiin,MOI)为2时,重组病毒感染细胞56 h后,重组蛋白的表达量达到峰值.结论:蝙蝠SAPS样冠状病

  4. Transgenic arthropods and the sterile insect technique

    International Nuclear Information System (INIS)

    The Sterile Insect Technique can benefit from transgenesis in three ways by creating; (1) genetically marked strains, (2) genetic sexing strains and (3) strains that induce molecular sterility in the field. Experience with the development of genetic sexing strains based on indicates that caution is required during the experimental evaluation of any potential transgenic strain. Two major scientific concerns involve the overall fitness of transgenic strains and their stability over time. The latter being very important especially when the extremely large numbers of insects that are mass reared is taken into account. Currently transformation events are random and it will probably be necessary to select suitable strains from many that are induced. The success of transformation itself in many insect species will enable many new strategies to be developed and tested. (author)

  5. Agricultural applications of insect ecological genomics.

    Science.gov (United States)

    Poelchau, Monica F; Coates, Brad S; Childers, Christopher P; Peréz de León, Adalberto A; Evans, Jay D; Hackett, Kevin; Shoemaker, DeWayne

    2016-02-01

    Agricultural entomology is poised to benefit from the application of ecological genomics, particularly the fields of biofuels generation and pest control. Metagenomic methods can characterize microbial communities of termites, wood-boring beetles and livestock pests, and transcriptomic approaches reveal molecular bases behind wood-digesting capabilities of these insects, leading to potential mechanisms for biofuel generation. Genome sequences are being exploited to develop new pest control methods, identify candidate antigens to vaccinate livestock, and discover RNAi target sequences and potential non-target effects in other insects. Gene content analyses of pest genome sequences and their endosymbionts suggest metabolic interdependencies between organisms, exposing potential gene targets for insect control. Finally, genome-wide association studies and genotyping by high-throughput sequencing promise to improve management of pesticide resistance. PMID:27436554

  6. Insect societies and the social brain.

    Science.gov (United States)

    Farris, Sarah M

    2016-06-01

    The 'social brain hypothesis,' the relationship between social behavior and brain size, does not apply to insects. In social insects, especially those of the Order Hymenoptera (ants, bees and wasps), sociality has not always increased individual behavioral repertoires and is associated with only subtle variation in the size of a higher brain center, the mushroom bodies. Rather than sociality, selection for novel visual behavior, perhaps spatial learning, has led to the acquisition of novel visual inputs and profound increases in mushroom body size. This occurred in nonsocial ancestors suggesting that the sensory and cognitive advantages of large mushroom bodies may be preadaptations to sociality. Adaptations of the insect mushroom bodies are more reliably associated with sensory ecology than social behavior. PMID:27436726

  7. Nonstructural protein Pns4 of rice dwarf virus is essential for viral infection in its insect vector

    OpenAIRE

    CHEN, Qian; Zhang, Linghua; Chen, Hongyan; Xie, Lianhui; Wei, Taiyun

    2015-01-01

    Background Rice dwarf virus (RDV), a plant reovirus, is mainly transmitted by the green rice leafhopper, Nephotettix cincticeps, in a persistent-propagative manner. Plant reoviruses are thought to replicate and assemble within cytoplasmic structures called viroplasms. Nonstructural protein Pns4 of RDV, a phosphoprotein, is localized around the viroplasm matrix and forms minitubules in insect vector cells. However, the functional role of Pns4 minitubules during viral infection in insect vector...

  8. RNA interference: Applications and advances in insect toxicology and insect pest management.

    Science.gov (United States)

    Kim, Young Ho; Soumaila Issa, Moustapha; Cooper, Anastasia M W; Zhu, Kun Yan

    2015-05-01

    Since its discovery, RNA interference (RNAi) has revolutionized functional genomic studies due to its sequence-specific nature of post-transcriptional gene silencing. In this paper, we provide a comprehensive review of the recent literature and summarize the current knowledge and advances in the applications of RNAi technologies in the field of insect toxicology and insect pest management. Many recent studies have focused on identification and validation of the genes encoding insecticide target proteins, such as acetylcholinesterases, ion channels, Bacillus thuringiensis receptors, and other receptors in the nervous system. RNAi technologies have also been widely applied to reveal the role of genes encoding cytochrome P450 monooxygenases, carboxylesterases, and glutathione S-transferases in insecticide detoxification and resistance. More recently, studies have focused on understanding the mechanism of insecticide-mediated up-regulation of detoxification genes in insects. As RNAi has already shown great potentials for insect pest management, many recent studies have also focused on host-induced gene silencing, in which several RNAi-based transgenic plants have been developed and tested as proof of concept for insect pest management. These studies indicate that RNAi is a valuable tool to address various fundamental questions in insect toxicology and may soon become an effective strategy for insect pest management. PMID:25987228

  9. Aerodynamics of the Smallest Flying Insects

    CERN Document Server

    Miller, Laura A; Hedrick, Ty; Robinson, Alice; Santhanakrishnan, Arvind; Lowe, Audrey

    2011-01-01

    We present fluid dynamics videos of the flight of some of the smallest insects including the jewel wasp, \\textit{Ampulex compressa}, and thrips, \\textit{Thysanoptera} spp. The fruit fly, \\textit{Drosophila melanogaster}, is large in comparison to these insects. While the fruit fly flies at $Re \\approx 120$, the jewel wasp flies at $Re \\approx 60$, and thrips flies at $Re \\approx 10$. Differences in the general structures of the wakes generated by each species are observed. The differences in the wakes correspond to changes in the ratio of lift forces (vertical component) to drag forces (horizontal component) generated.

  10. Studying insect diversity in the tropics.

    OpenAIRE

    Godfray, H. C.; Lewis, T; Memmott, J

    1999-01-01

    Understanding the extent and causes of insect diversity in the humid tropics is one of the major challenges in modern ecology. We review some of the current approaches to this problem, and discuss how future progress may be made. Recent calculations that there may be more than 30 million species of insect on earth have focused attention on the magnitude of this problem and stimulated several new lines of research (although the true figure is now widely thought to be between five and ten milli...

  11. Chemistry and biology of insect bioluminescence

    International Nuclear Information System (INIS)

    Basic aspects on the Chemistry and Biology of bioluminescence are reviewed, with emphasis on insects. Data from the investigation of Lampyridae (fireflies) are collected from literature. With regard to Elateridae (click beetles) and Phengodidae (rail road worms), the least explored families of luminescent insects, new data are presented on the following aspects: (i) 'in vivo' emission spectra, (ii) chemical nature of the luciferin, (iii) conection between bioluminescence and 'oxygen toxicity' as a result of molecular oxygen storage and (iv) the role of light emission by larvae and pupae. (Author)

  12. A non-autonomous insect piggyBac trasposable element is mobile in tobacco

    Science.gov (United States)

    The piggyBac transposable element, originally isolated from a virus in an insect cell line, is a valuable molecular tool for transgenesis and mutagenesis of invertebrates. For heterologous transgenesis in a variety of mammals, transfer of the piggyBac transposable element from an ectopic plasmid onl...

  13. Shrinkage of body size of small insects: A possible link to global warming?

    Energy Technology Data Exchange (ETDEWEB)

    He Jihuan [College of Science, Donghua University, 1882 Yan' an Xilu Road, Shanghai 200051 (China)]. E-mail: jhhe@dhu.edu.cn

    2007-11-15

    The increase of global mean surface temperature leads to the increase of metabolic rate. This might lead to an unexpected threat from the small insect world. Global warming shrinks cell size, shorten lifespan, and accelerate evolution. The present note speculates on possible connections between allometry and E-infinity theory.

  14. The Comet assay in insects--Status, prospects and benefits for science.

    Science.gov (United States)

    Augustyniak, Maria; Gladysz, Marcin; Dziewięcka, Marta

    2016-01-01

    The Comet assay has been recently adapted to investigate DNA damage in insects. The first reports of its use in Drosophila melanogaster appeared in 2002. Since then, the interest in the application of the Comet assay to studies of insects has been rapidly increasing. Many authors see substantial potential in the use of the Comet assay in D. melanogaster for medical toxicology studies. This application could allow the testing of drugs and result in an understanding of the mechanisms of action of toxins, which could significantly influence the limited research that has been performed on vertebrates. The possible perspectives and benefits for science are considered in this review. In the last decade, the use of the Comet assay has been described in insects other than D. melanogaster. Specifically, methods to prepare a cell suspension from insect tissues, which is a difficult task, were analyzed and compared in detail. Furthermore, attention was paid to any differences and modifications in the research protocols, such as the buffer composition and electrophoresis conditions. Various scientific fields in addition to toxicological and ecotoxicological research were considered. We expect the Comet assay to be used in environmental risk assessments and to improve our understanding of many important phenomena of insect life, such as metamorphosis, molting, diapause and quiescence. The use of this method to study species that are of key importance to humans, such as pests and beneficial insects, appears to be highly probable and very promising. The use of the Comet assay for DNA stability testing in insects will most likely rapidly increase in the future.

  15. Diseases in insects produced for food and feed

    DEFF Research Database (Denmark)

    Eilenberg, Jørgen; Vlak, J.M.; Nielsen-Leroux, C.;

    2015-01-01

    Increased production of insects on a large scale for food and feed will likely lead to many novel challenges, including problems with diseases. We provide an overview of important groups of insect pathogens, which can cause disease in insects produced for food and feed. Main characteristics of each...... pathogen group (viruses, bacteria, fungi, protists and nematodes) are described and illustrated, with a selection of examples from the most commonly produced insect species for food and feed. Honeybee and silkworm are mostly produced for other reasons than as human food, yet we can still use them...... as examples to learn about emergence of new diseases in production insects. Results from a 2014 survey about insect diseases in current insect production systems are presented for the first time. Finally, we give some recommendations for the prevention and control of insect diseases. Key words: disease...

  16. Acquisition of full-length viral helicase domains by insect retrotransposon-encoded polypeptides

    Directory of Open Access Journals (Sweden)

    Ekaterina eLazareva

    2015-12-01

    Full Text Available Recent metagenomic studies in insects identified many sequences unexpectedly closely related to plant virus genes. Here we describe a new example of this kind, insect R1 LINEs with an additional C-terminal domain in their open reading frame 2. This domain is similar to NTPase/helicase (SF1H domains, which are found in replicative proteins encoded by plant viruses of the genus Tobamovirus. We hypothesize that the SF1H domain could be acquired by LINEs, directly or indirectly, upon insect feeding on virus-infected plants. Possible functions of this domain in LINE transposition and involvement in LINEs counteraction the silencing-based cell defense against retrotransposons are discussed.

  17. The effect of gamma irradiation on insect pest of rice in storage

    International Nuclear Information System (INIS)

    This study was conducted to determine the effect of gamma irradiation on insect pest of rice, stored for a period of 24 months, and packed in four different packaging materials. They were then exposed to gamma radiation using Gamma Cell 220, in a 60Co source. Samples were randomly sampled at the initial storage period and there after at 3 months interval. At each sampling time the grain weight loss and insect count, both dead and alive, were determined. The increasing dosages of irradiation did not show any consistent effect on the insect population in all the four packaging materials which indicated that the rice was already infested even before it was irradiated. The range of percentage weight loss for all the dosages of irradiation in all of the four packaging materials is 0.99 to 2.02. (A.J.)

  18. Learning pattern recognition and decision making in the insect brain

    Science.gov (United States)

    Huerta, R.

    2013-01-01

    We revise the current model of learning pattern recognition in the Mushroom Bodies of the insects using current experimental knowledge about the location of learning, olfactory coding and connectivity. We show that it is possible to have an efficient pattern recognition device based on the architecture of the Mushroom Bodies, sparse code, mutual inhibition and Hebbian leaning only in the connections from the Kenyon cells to the output neurons. We also show that despite the conventional wisdom that believes that artificial neural networks are the bioinspired model of the brain, the Mushroom Bodies actually resemble very closely Support Vector Machines (SVMs). The derived SVM learning rules are situated in the Mushroom Bodies, are nearly identical to standard Hebbian rules, and require inhibition in the output. A very particular prediction of the model is that random elimination of the Kenyon cells in the Mushroom Bodies do not impair the ability to recognize odorants previously learned.

  19. EXPRESSION OF CHICKEN INTERLEUKIN - 18 MATURATION PROTEIN GENE IN INSECT CELLS AND IDENTIFICATION OF BIOACTIVITY OF ITS EXPRESSED PROTEIN%鸡白细胞介素18成熟蛋白在昆虫杆状病毒系统中的表达及其活性检测

    Institute of Scientific and Technical Information of China (English)

    范忠玲; 王婷婷; 马凤龙; 胡敬东

    2011-01-01

    To obtain the recombinant Bacmid,the mature chicken interleukin - 18 protein (mChIL - 18) gene was subcloned into the baculovirus transfer vector pFastBac HTb and the recombinant plasmid was transformed into competent DH10BacTME. Coli cells containing bacu - lovirus shuttle vector bacmid. Then the purified recombinant bacmid was transfected into sf9 insect cells by the method of using lipofectin for producing integrated recombinant baculo - virus. Infected the sf9 with the higher baculoviral stock for expressing protein and harvested the supernatant and cells in different times. The expressed mChIL -18 protein was analyzed by SDS - PACE, detected by Western blotting and IFA.and the results demonstrated that recombinant protein of 23kDa in molecular mass was expressed successfully in insect cells. The experiment of VSV inhibition showed that the expression of mChIL- 18 protein have relativity high bioacti - vity. In summary, the active mChIL - 18 protein was expressed successfully in baculovirus ex - pression system.%首先将鸡白细胞介素18成熟蛋白(mature chicken interleukin - 18,mChIL - 18)基因亚克隆至杆状病毒转移载体pFastBac HTb上,然后转化至含穿梭载体Bacmid的受体菌E.coli DH10BacTM中,构建重组Bacmid (rBacmid).通过脂质体介导法将纯化的rBacmid转染sf9细胞,获得完整重组杆状病毒,将达到一定滴度的重组杆状病毒感染sf9,收获感染后不同时间段的培养上清和细胞,经SDS - PAGE分析、Westem - blotting和间接免疫荧光(IFA)检测,结果表明,分子量约为23KDa的重组蛋白在昆虫细胞中获得了表达;鸡淋巴细胞转化试验和水疱性口炎病毒( VSV)抑制试验表明,表达产物具有良好的生物学活性.结论:在杆状病毒表达系统中成功表达了有活性的mChIL - 18蛋白.

  20. Insect Pests of Field Crops. MP-28.

    Science.gov (United States)

    Burkhardt, Chris C.

    This document addresses the principles of field crop insect control through biological, mechanical, and chemical processes. Identification, life history, damage, pesticides, pesticide use and environmental considerations are presented for the major pests of corn, alfalfa, beans, small grains, sugar beets, and potatoes. Each section is accompanied…

  1. Measuring Asymmetry in Insect-Plant Networks

    International Nuclear Information System (INIS)

    In this work we focus on interaction networks between insects and plants and in the characterization of insect plant asymmetry, an important issue in coevolution and evolutionary biology. We analyze in particular the asymmetry in the interaction matrix of animals (herbivorous insects) and plants (food resource for the insects). Instead of driving our attention to the interaction matrix itself we derive two networks associated to the bipartite network: the animal network, D1, and the plant network, D2. These networks are constructed according to the following recipe: two animal species are linked once if they interact with the same plant. In a similar way, in the plant network, two plants are linked if they interact with the same animal. To explore the asymmetry between D2 and D1 we test for a set of 23 networks from the ecologic literature networks: the difference in size, ΔL, clustering coefficient difference, ΔC, and mean connectivity difference, Δ. We used a nonparametric statistical test to check the differences in ΔL, ΔC and Δ. Our results indicate that ΔL and Δ show a significative asymmetry.

  2. Measuring Asymmetry in Insect-Plant Networks

    Energy Technology Data Exchange (ETDEWEB)

    Cruz, Claudia P T [Programa de Pos-Graduacao em Fisica, Universidade Federal do Rio Grande do Norte, UFRN - Campus Universitario, Lagoa Nova, CEP 59078 972, Natal, RN (Brazil); De Almeida, Adriana M [Departamento de Botanica, Ecologia e Zoologia, Centro de Biociencias, Universidade Federal do Rio Grande do Norte, UFRN - Campus Universitario, Lagoa Nova, CEP 59078 972, Natal, RN (Brazil); Corso, Gilberto, E-mail: claudia@dfte.ufrn.br, E-mail: adrianam@ufrn.br, E-mail: corso@cb.ufrn.br [Departamento de Biofisica e Farmacologia, Centro de Biociencias, Universidade Federal do Rio Grande do Norte, UFRN - Campus Universitario, Lagoa Nova, CEP 59078 972, Natal, RN (Brazil)

    2011-03-01

    In this work we focus on interaction networks between insects and plants and in the characterization of insect plant asymmetry, an important issue in coevolution and evolutionary biology. We analyze in particular the asymmetry in the interaction matrix of animals (herbivorous insects) and plants (food resource for the insects). Instead of driving our attention to the interaction matrix itself we derive two networks associated to the bipartite network: the animal network, D{sub 1}, and the plant network, D{sub 2}. These networks are constructed according to the following recipe: two animal species are linked once if they interact with the same plant. In a similar way, in the plant network, two plants are linked if they interact with the same animal. To explore the asymmetry between D{sub 2} and D{sub 1} we test for a set of 23 networks from the ecologic literature networks: the difference in size, {Delta}L, clustering coefficient difference, {Delta}C, and mean connectivity difference, {Delta}. We used a nonparametric statistical test to check the differences in {Delta}L, {Delta}C and {Delta}. Our results indicate that {Delta}L and {Delta} show a significative asymmetry.

  3. Insects of war, terror and torture

    Science.gov (United States)

    From plagues to malaria transmission, insects and other arthropods have been natural or intentional health and agricultural threats to military and civilian populations throughout human history. The success or failure of military operations frequently has been determined by correctly anticipating in...

  4. Hunting for insect pathogens: A genomics approach

    Science.gov (United States)

    Emerging methods within the field of genomics have increased the number of insect pathogens being discovered and characterized each year. These pathogens provide a rich resource for biological control agents, gene expression systems, and other molecular tools. Using Metagenomics, and gene expression...

  5. Insects: Little Things That Run the World

    Science.gov (United States)

    Tilley, Luke

    2014-01-01

    Insects are easily the most abundant and diverse group of animals, with over 24,000 species in the UK alone. They can be found in almost every habitat on Earth and are fundamentally important to ecology, conservation, food production, animal and human health, and biodiversity. They are a prominent feature of almost every food web in the UK and…

  6. Natural products from microbes associated with insects

    DEFF Research Database (Denmark)

    Beemelmanns, Christine; Guo, Huijuan; Rischer, Maja;

    2016-01-01

    Here we review discoveries of secondary metabolites from microbes associated with insects. We mainly focus on natural products, where the ecological role has been at least partially elucidated, and/or the pharmaceutical properties evaluated, and on compounds with unique structural features. We...

  7. Pathogenesis induced by (recombinant) baculoviruses in insects.

    NARCIS (Netherlands)

    Flipsen, J.Th.M.

    1995-01-01

    Infection of insect larvae by a baculovirus leads to cessation of feeding and finally to the death of the larva. Under optimal conditions this process may take as little as five days during which the virus multiplies approximately a billion times and transforms 30% of the larval weight into viral pr

  8. Mode of action of insect repellents

    Science.gov (United States)

    The mode of action of DEET and other insect repellents has been a topic of interest since the discovery of DEET in the mid twentieth century. Nearly 60 years have passed since DEET applied topically to the skin was shown to be effective in preventing mosquito bites. With the discovery and characte...

  9. Insect Resistant Cotton COT67B

    OpenAIRE

    Directorate, Issued by Health Canada's Food

    2014-01-01

    Health Canada has notified Syngenta Seeds Canada Inc. that it has no objection to the sale of food derived from Insect Resistant Cotton COT67B. The Department conducted a comprehensive assessment of this cotton event according to its Guidelines for the Safety Assessment of Novel Foods. These Guidelines are based upon internationally accepted principles for establishing the safety of foods with novel traits.

  10. Riparian forestry management and adult stream insects

    Directory of Open Access Journals (Sweden)

    R. A. Briers

    2004-01-01

    Full Text Available The impacts of coniferous plantation forestry on the biology of upland streams in the UK are firmly established. Whilst benthic communities have been well studied, very little research has considered the impacts of riparian forestry management on adult stream insects, yet the essentially terrestrial adult (reproductive phase may be important in determining the abundance and distribution of larval stages. Riparian vegetation has a potentially strong impact on survival and success of adult stages through alteration of microclimate, habitat structure and potential food sources, in addition to effects carried over from larval stages. Here, current riparian management strategies are analysed in the light of available information on the ecology of adult stream insects. On the whole, management practices appear to favour adult stream insects, although an increase in tree cover in riparian areas could be beneficial, by providing more favourable microclimatic conditions for adults. This conclusion is drawn based on rather limited information, and the need for further research into the effects of riparian forestry management on adult stream insects is highlighted. Keywords: microclimate, plantation, life history, riparian vegetation

  11. Biomimetic visual detection based on insect neurobiology

    Science.gov (United States)

    O'Carroll, David C.

    2001-11-01

    With a visual system that accounts for as much as 30% of the lifted mass, flying insects such as dragonflies and hoverflies invest more in vision than any other animal. Impressive visual performance is subserved by a surprisingly simple visual system. In a typical insect eye, between 2,000 and 30,000 pixels in the image are analyzed by fewer than 200,000 neurons in underlying neural circuits. The combination of sophisticated visual processing with an approachable level of complexity has made the insect visual system a leading model for biomimetic approaches to computer vision. Much neurobiological research has focused on neural circuits used for detection of moving patterns (e.g. optical flow during flight) and moving targets (e.g. prey). Research from several labs has led to great advances in our understanding of the neural mechanisms involved, and has spawned neuromorphic hardware based on key processes identified in neurobiological experiments. Despite its attractions, the highly non-linear nature of several key stages in insect visual processing presents a challenge to understanding. I will describe examples of adaptive elements of neural circuits in the fly visual system which analyze the direction and velocity of wide-field optical flow patterns and the result of experiments that suggest that these non-linearities may contribute to robust responses to natural image motion.

  12. The adaptation of insects to protease inhibitors

    NARCIS (Netherlands)

    Jongsma, M.A.; Bolter, C.J.

    1997-01-01

    Plants and herbivores have been co-evolving for thousands of years, and as a result, plants have defence mechanisms that offer protection against many herbivores such as nematodes, insects, birds and mammals. Only when a herbivore has managed to adapt to these defence mechanisms does it have the pot

  13. Wolbachia symbiosis and insect immune response

    Institute of Scientific and Technical Information of China (English)

    Stefanos Siozios; Panagiotis Sapountzis; Panagiotis Ioannidis; Kostas Bourtzis

    2008-01-01

    Bacterial intracellular symbiosis is very common in insects, having significant consequences in promoting the evolution of life and biodiversity. The bacterial group that has recently attracted particular attention is Wolbachia pipientis which probably represents the most ubiquitous endosymbiont on the planet. W. pipientis is a Gram-negative obligatory intracellular and maternally transmitted α-proteobacterium, that is able to establish symbiotic associations with arthropods and nematodes. In arthropods, Wolbachia pipientis infections have been described in Arachnida, in Isopoda and mainly in Insecta. They have been reported in almost all major insect orders including Diptera, Coleoptera, Hemiptera,Hymenoptera, Orthoptera and Lepidoptera. To enhance its transmission, W. pipientis can manipulate host reproduction by inducing parthenogenesis, feminization, male killing and cytoplasmic incompatibility. Several polymerase chain reaction surveys have indicated that up to 70% of all insect species may be infected with W. pipientis. How does W. pipientis manage to get established in diverse insect host species? How is this intracellular bacterial symbiont species so successful in escaping the host immune response? The present review presents recent advances and ongoing scientific efforts in the field. The current body of knowledge in the field is summarized, revelations from the available genomic information are presented and as yet unanswered questions are discussed in an attempt to present a comprehensive picture of the unique ability of W. pipientis to establish symbiosis and to manipulate reproduction while evading the host's immune system.

  14. Insect pest control newsletter. No. 65

    International Nuclear Information System (INIS)

    The concept of Area-wide Integrated Pest Management (AW-IPM) is defined as IPM applied against an entire pest population within a delimited geographic area. Area-wide intervention strategies require more planning and ecological understanding, longer-term commitment, a minimum infrastructure and a coordinated implementation by farmers and all other stakeholders. The spatial distribution of the pest population has to be considered not only in surrounding cultivated areas, but also in non-cultivated areas. It also involves considering the temporal distribution of the pest to determine the periods when the pest is most susceptible to preventive, rather than remedial, interventions. In 1998 FAO and the Agency sponsored the First International Conference on 'Area-Wide Control of Insect Pests, Integrating the Sterile Insect and Related Nuclear and other Techniques' in Penang, Malaysia. This Conference greatly increased the interest and awareness concerning the AW-IPM approach to insect pest control. Since then, many new technical innovations have been introduced; a better regulatory framework is being developed to encourage the involvement of the private sector, and more FAO and Agency Member States are integrating insect pest control methods on an areawide basis. Over the past months we have been heavily involved in preparing for the Second FAO/IAEA International Conference on 'Area-Wide Control of Insect Pests: Integrating the Sterile Insect and Related Nuclear and Other Techniques', which was held from 9-13 May in Vienna. The response and interest of scientists and governments, as well as the private sector and sponsors were once more very encouraging. The conference took place with the participation of over 300 delegates from 86 countries, nine international organization, and eight exhibitors. It covered the area-wide approach again in a very broad sense, including the development and integration of many non-SIT technologies, as well as genetic research on cytoplasmic

  15. The sterile insect technique [videorecording]: An environment-friendly method of insect pest suppression and eradication

    International Nuclear Information System (INIS)

    Using graphic displays and clips of actual laboratory and field activities related to the sterile insect technique (SIT), the video covers various topics on the principles and applications of this technique

  16. Obligate symbiont involved in pest status of host insect

    OpenAIRE

    Hosokawa, Takahiro; Kikuchi, Yoshitomo; Shimada, Masakazu; Fukatsu, Takema

    2007-01-01

    The origin of specific insect genotypes that enable efficient use of agricultural plants is an important subject not only in applied fields like pest control and management but also in basic disciplines like evolutionary biology. Conventionally, it has been presupposed that such pest-related ecological traits are attributed to genes encoded in the insect genomes. Here, however, we report that pest status of an insect is principally determined by symbiont genotype rather than by insect genotyp...

  17. Who's the pest? Imagining human–insect futures beyond antagonism

    OpenAIRE

    Last, Angela

    2014-01-01

    Joining the effort to reimagine our relationships with insects, the Wellcome Collection's ‘Who's the Pest?’ programme attempts to challenge the stigma of insects as ill-disposed ‘bugs’. The article reviews two events in the series, the workshop ‘Insects au gratin’ and the debate ‘Insects vs. humans’, and places them in the context of recent engagements with ‘pests’ in the public realm.

  18. Effect of light and botanical species richness on insect diversity

    OpenAIRE

    De Cauwer, Benny; Reheul, Dirk; De Laethauwer, Sarah; Nijs, Ivan; Milbau, Ann

    2006-01-01

    International audience Composition and diversity of flying insects was assessed within and along one-year-old sown/unsown field margin strips installed along both the shaded and unshaded side of an old lane of beeches. Investigated factors were light regime, plant community and monitoring position. Both insect composition and spatial preference of insect families was strongly dependent on light regime, field margin type and monitoring position. The number of insect families preferring the ...

  19. Evolution of SUMO Function and Chain Formation in Insects

    OpenAIRE

    Ureña, Enric; Pirone, Lucia; Chafino, Silvia; Pérez, Coralia; Sutherland, James D.; Lang, Valérie; Rodriguez, Manuel S; Lopitz-Otsoa, Fernando; Francisco J Blanco; Barrio, Rosa; Martín, David

    2015-01-01

    SUMOylation, the covalent binding of Small Ubiquitin-like Modifier (SUMO) to target proteins, is a posttranslational modification that regulates critical cellular processes in eukaryotes. In insects, SUMOylation has been studied in holometabolous species, particularly in the dipteran Drosophila melanogaster, which contains a single SUMO gene (smt3). This has led to the assumption that insects contain a single SUMO gene. However, the analysis of insect genomes shows that basal insects contain ...

  20. Insect diversity of Bukit Hampuan Forest Reserve, Sabah, Malaysia

    OpenAIRE

    A.Y.C. Chung; S.K.F. Chew; R. Majapun; R. Nilus

    2013-01-01

    An insect diversity survey was carried out at Bukit Hampuan Forest Reserve, adjacent to Kinabalu Park in Sabah, Malaysia. The nocturnal insect diversity was very high, with a mean of 113 species recorded from one square metre of light-trapping cloth. Diurnal insects were sampled using sweep nets and fine forceps. A total of 19 Bornean endemic insect species were recorded, comprising 15 moth and four beetle species. A few of the endemic moths are confined to Sabah, namely Buzara saikehi, Cyan...

  1. Selenium assimilation and loss by an insect predator and its relationship to Se subcellular partitioning in two prey types

    International Nuclear Information System (INIS)

    Subcellular selenium (Se) distributions in the oligochaete Tubifex tubifex and in the insect Chironomus riparius did not vary with Se exposure duration, which was consistent with the observations that the duration of prey Se exposure had little influence on either Se assimilation or loss by a predatory insect (the alderfly Sialis velata). However, these two prey types differed in how Se was distributed in their cells. Overall, the predator assimilated a mean of 66% of the Se present in its prey, which was similar to the mean percentage of Se in prey cells (62%) that was theoretically available for uptake (that is, Se in the protein and organelle fractions). Likewise, data for cadmium, nickel and thallium suggest that predictions of trace element transfer between prey and predator are facilitated by considering the subcellular partitioning of these contaminants in prey cells. - Selenium assimilation by a predatory aquatic insect depends on Se availability in the cells of its prey

  2. Similarities between decapod and insect neuropeptidomes

    Science.gov (United States)

    2016-01-01

    Background. Neuropeptides are important regulators of physiological processes and behavior. Although they tend to be generally well conserved, recent results using trancriptome sequencing on decapod crustaceans give the impression of significant differences between species, raising the question whether such differences are real or artefacts. Methods. The BLAST+ program was used to find short reads coding neuropeptides and neurohormons in publicly available short read archives. Such reads were then used to find similar reads in the same archives, and the DNA assembly program Trinity was employed to construct contigs encoding the neuropeptide precursors as completely as possible. Results. The seven decapod species analyzed in this fashion, the crabs Eriocheir sinensis, Carcinus maenas and Scylla paramamosain, the shrimp Litopenaeus vannamei, the lobster Homarus americanus, the fresh water prawn Macrobrachium rosenbergii and the crayfish Procambarus clarkii had remarkably similar neuropeptidomes. Although some neuropeptide precursors could not be assembled, in many cases individual reads pertaining to the missing precursors show unambiguously that these neuropeptides are present in these species. In other cases, the tissues that express those neuropeptides were not used in the construction of the cDNA libraries. One novel neuropeptide was identified: elongated PDH (pigment dispersing hormone), a variation on PDH that has a two-amino-acid insertion in its core sequence. Hyrg is another peptide that is ubiquitously present in decapods and is likely a novel neuropeptide precursor. Discussion. Many insect species have lost one or more neuropeptide genes, but apart from elongated PDH and hyrg all other decapod neuropeptides are present in at least some insect species, and allatotropin is the only insect neuropeptide missing from decapods. This strong similarity between insect and decapod neuropeptidomes makes it possible to predict the receptors for decapod neuropeptides

  3. Similarities between decapod and insect neuropeptidomes.

    Science.gov (United States)

    Veenstra, Jan A

    2016-01-01

    Background. Neuropeptides are important regulators of physiological processes and behavior. Although they tend to be generally well conserved, recent results using trancriptome sequencing on decapod crustaceans give the impression of significant differences between species, raising the question whether such differences are real or artefacts. Methods. The BLAST+ program was used to find short reads coding neuropeptides and neurohormons in publicly available short read archives. Such reads were then used to find similar reads in the same archives, and the DNA assembly program Trinity was employed to construct contigs encoding the neuropeptide precursors as completely as possible. Results. The seven decapod species analyzed in this fashion, the crabs Eriocheir sinensis, Carcinus maenas and Scylla paramamosain, the shrimp Litopenaeus vannamei, the lobster Homarus americanus, the fresh water prawn Macrobrachium rosenbergii and the crayfish Procambarus clarkii had remarkably similar neuropeptidomes. Although some neuropeptide precursors could not be assembled, in many cases individual reads pertaining to the missing precursors show unambiguously that these neuropeptides are present in these species. In other cases, the tissues that express those neuropeptides were not used in the construction of the cDNA libraries. One novel neuropeptide was identified: elongated PDH (pigment dispersing hormone), a variation on PDH that has a two-amino-acid insertion in its core sequence. Hyrg is another peptide that is ubiquitously present in decapods and is likely a novel neuropeptide precursor. Discussion. Many insect species have lost one or more neuropeptide genes, but apart from elongated PDH and hyrg all other decapod neuropeptides are present in at least some insect species, and allatotropin is the only insect neuropeptide missing from decapods. This strong similarity between insect and decapod neuropeptidomes makes it possible to predict the receptors for decapod neuropeptides

  4. ERK signaling couples nutrient status to antiviral defense in the insect gut.

    Science.gov (United States)

    Xu, Jie; Hopkins, Kaycie; Sabin, Leah; Yasunaga, Ari; Subramanian, Harry; Lamborn, Ian; Gordesky-Gold, Beth; Cherry, Sara

    2013-09-10

    A unique facet of arthropod-borne virus (arbovirus) infection is that the pathogens are orally acquired by an insect vector during the taking of a blood meal, which directly links nutrient acquisition and pathogen challenge. We show that the nutrient responsive ERK pathway is both induced by and restricts disparate arboviruses in Drosophila intestines, providing insight into the molecular determinants of the antiviral "midgut barrier." Wild-type flies are refractory to oral infection by arboviruses, including Sindbis virus and vesicular stomatitis virus, but this innate restriction can be overcome chemically by oral administration of an ERK pathway inhibitor or genetically via the specific loss of ERK in Drosophila intestinal epithelial cells. In addition, we found that vertebrate insulin, which activates ERK in the mosquito gut during a blood meal, restricts viral infection in Drosophila cells and against viral invasion of the insect gut epithelium. We find that ERK's antiviral signaling activity is likely conserved in Aedes mosquitoes, because genetic or pharmacologic manipulation of the ERK pathway affects viral infection of mosquito cells. These studies demonstrate that ERK signaling has a broadly antiviral role in insects and suggest that insects take advantage of cross-species signals in the meal to trigger antiviral immunity.

  5. Les épreuves d'insectes en Amazonie - Insect Ordeals in Amazonia

    OpenAIRE

    Césard, Nicolas

    2005-01-01

    International audience; People from the Amazon make use of insects such as ants and wasps, on different occasions, such as the early-reported “ant ordeals” initiation rites. Travel stories and more ethnographic journeys describe cruel and often spectacular practices in which men, women and children, bravely endure bites from a dozen to hundreds of insects. However the meanings given to those practices leave out most of the time the ontological concepts of the groups described, as well as thei...

  6. Exploring the Insect World, An Outdoor Teaching Technique.

    Science.gov (United States)

    Rillo, Thomas J.

    Information about the insect world and its advantages for the elementary classroom teacher is given in this paper, along with activities which can teach students about insects. The insect world tends to be noticed by the average person only when the small creatures become pests or inhabit man's abode. However, young students have a sharp sense of…

  7. Coconut leaf bioactivity toward generalist maize insect pests

    Science.gov (United States)

    Tropical plants are often more resistant to insects than temperate plants due to evolution of robust defenses to cope with a more constant insect threat. Coconut (Cocos nucifera L.) has very few chewing leaf feeding insect pests and was tested against two omnivorous leaf feeding caterpillar species,...

  8. Job Grading Standard for Insects Production Worker WG-5031.

    Science.gov (United States)

    Civil Service Commission, Washington, DC. Bureau of Policies and Standards.

    The standard is for grading nonsupervisory jobs involved in reproducing, collecting, and caring for insect collections. The work requires practical knowledge of the characteristics of insects and their needs, and skill in observing and handling them. The levels of insects production worker WG-3, WG-4, and WG-5 are differentiated by describing the…

  9. Diseases in insects produced for food and feed

    NARCIS (Netherlands)

    Eilenberg, J.; Vlak, J.M.; Nielsen-LeRoux, C.; Capellozza, S.; Jensen, A.B.

    2015-01-01

    Increased production of insects on a large scale for food and feed will likely lead to many novel challenges, including problems with diseases. We provide an overview of important groups of insect pathogens, which can cause disease in insects produced for food and feed. Main characteristics of each

  10. Social insects: from selfish genes to self organisation and beyond

    DEFF Research Database (Denmark)

    Boomsma, Jacobus Jan; Franks, Nigel R.

    2006-01-01

    Selfish gene and self-organisation approaches have revolutionised the study of social insects and have provided unparalleled insights into the highly sophisticated nature of insect social evolution. Here, we briefly review the core programs and interfaces with communication and recognition studies...... that characterise these fields today, and offer an interdisciplinary future perspective for the study of social insect evolutionary biology....

  11. Converting insect colony waste into a potting susbstrate.

    Science.gov (United States)

    Rearing insect generates both a solid and semisolid waste that is generally discarded in landfills. A study was initiated to determine if the semi-solid insect colony waste product and vermiculite used in insect rearing could be combined and used as a growth substrate for plants. The semi-solid larv...

  12. The insect cookbook : food for a sustainable planet

    NARCIS (Netherlands)

    Huis, van A.; Gurp, van H.; Dicke, M.

    2014-01-01

    In The Insect Cookbook, two entomologists and a chef make the case for insects as a sustainable source of protein for humans and a necessary part of our future diet. They provide consumers and chefs with the essential facts about insects for culinary use, with recipes simple enough to make at home y

  13. Grain sorghum hybrid resistance to insect and bird damage-2014

    Science.gov (United States)

    Thirty seven grain sorghum hybrids were evaluated for resistance to insect and bird damage in 2014 in Tifton, and a total of 10 insect pests were observed. While sorghum midge and bird damage was relatively low, sorghum webworm and aphid damage was high. Those insects in order of importance are: sug...

  14. 25 CFR 163.31 - Insect and disease control.

    Science.gov (United States)

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Insect and disease control. 163.31 Section 163.31 Indians... Management and Operations § 163.31 Insect and disease control. (a) The Secretary is authorized to protect and preserve Indian forest land from disease or insects (Sept. 20, 1922, Ch. 349, 42 Stat. 857). The...

  15. Insect-attracting and antimicrobial properties of antifreeze for monitoring insect pests and natural enemies in stored corn

    Science.gov (United States)

    Insect infestations in stored grain cause extensive damage worldwide. Storage insect pests including the Indianmeal moth, Plodia interpunctella (Hübner) (Lepidoptera: Pyralidae), Sitophilus spp. (Coleoptera: Curculionidae) and their natural enemies [e.g., Cephalonomia tarsalis (Ashmead) (Hymenopter...

  16. 干扰水稻瘤矮病毒(RGDV)非结构蛋白(Pns12)的表达抑制病毒在介体昆虫培养细胞内的复制%Knockdown of Nonstructural Protein(Pns12) of Rice gall dwarf virus (RGDV) Inhibits Viral Replication in Insect Vector Cells

    Institute of Scientific and Technical Information of China (English)

    郑立敏; 刘华敏; 陈红燕; 贾东升; 谢联辉; 魏太云

    2014-01-01

    水稻瘤矮病毒(Rice gall dwarf virus, RGDV)属呼肠孤病毒科(Reoviridae)植物呼肠孤病毒属(Phytoreovirus),由介体电光叶蝉(Recilia dorsalis)以持久增殖型方式传播,其基因组第12条片段编码的非结构蛋白(nonstructural protein, Pns12)是提供病毒复制和子代病毒粒体装配场所——病毒原质(viroplasm)的组分之一。为了明确Pns12在RGDV侵染介体电光叶蝉培养细胞中的功能,本研究通过原核表达的Pns12蛋白免疫注射兔(Oryctolagus cuniculus),制备Pns12抗体,并应用免疫荧光标记和RNA干扰(RNA interference, RNAi)技术研究Pns12在介体培养细胞内的定位和参与病毒原质形成的过程。共聚焦显微镜观察到,病毒侵染的细胞中,与荧光素交联的Pns12抗体特异地标记在病毒原质上。干扰Pns12蛋白表达后,可有效地阻碍病毒原质的形成、子代病毒粒体的组装和病毒非结构蛋白Pns12和外壳蛋白P8蛋白的表达,表明Pns12作为病毒原质的组分参与了RGDV在介体培养细胞内的复制。也表明,Pns12可作为理想的靶标用于阻断电光叶蝉携带和传播RGDV。%Rice gall dwarf virus(RGDV), the genus Phytoreovirus in the family Reoviridae, is transmitted by the leafhopper vector(Recilia dorsalis) in a persistent-propagative manner. Nonstructural protein(Pns12), encoded by segment 12 of RGDV, is one of the components of viroplasm which is the site for viral replication and assembly of progeny virons during viral infection in its insect vector cells. In this study, to investigate the functional role of Pns12 in the formation of viroplasm in its insect vector cells, the polyclonal antibody against Pns12 was prepared and purified, then conjugated to fluorescein isothiocyanate. The immunoglobulin G(IgG) of P8 was purified and conjugated to rhadamine. Immunofluorescence microscopy demonstrated that Pns12 antibodies specifically distributed in the viroplasm matrix during RGDV infection

  17. A Review on the Fascinating World of Insect Resources: Reason for Thoughts

    OpenAIRE

    Lokeshwari, R. K.; Shantibala, T.

    2010-01-01

    Insect resources are vast and diverse due to their enormous diversity. The exploitation and utilization of insect resources is broadly classified into four different categories. The first category is the insects of industrial resources. This level includes the utilization of silk worm, honeybee, lac insect, dye insect, and aesthetic insect. The second category is the utilization of insects for edible and therapeutic purposes. Insects are high in protein and many are rich sources of vitamins a...

  18. Selectable markers with potential activity against insects, plus other insect-oriented strategies for mycotoxin reduction in Midwest corn

    Science.gov (United States)

    Reduction of insect damage has the potential to greatly reduce the levels of mycotoxins in corn, as studies with Bt corn have shown. However, the large number of insect species involved necessitates the development of comprehensive insect control to most effectively utilize this strategy. One stra...

  19. External Insect Morphology: A Negative Factor in Attitudes toward Insects and Likelihood of Incorporation in Future Science Education Settings

    Science.gov (United States)

    Wagler, Ron; Wagler, Amy

    2012-01-01

    This study investigated if the external morphology of an insect had a negative effect on United States (US) preservice elementary teacher's attitudes toward insects and beliefs concerning the likelihood of incorporating insects into future science education settings. 270 US kindergarten through sixth grade preservice elementary teachers…

  20. Spectral composition of light sources and insect phototaxis, with an evaluation of existing spectral response models. Journal of Insect Conservation

    NARCIS (Netherlands)

    Grunsven, van R.H.A.; Donners, M.; Boekee, K.; Tichelaar, I.; Geffen, van K.G.; Groenendijk, D.; Berendse, F.; Veenendaal, E.M.

    2014-01-01

    Artificial illumination attracts insects, but to what extent light attracts insects, depends on the spectral composition of the light. Response models have been developed to predict the attractiveness of artificial light sources. In this study we compared attraction of insects by existing light sour

  1. Multi-factor climate change effects on insect herbivore performance

    DEFF Research Database (Denmark)

    Scherber, Christoph; Gladbach, David J; Stevnbak, Karen;

    2013-01-01

    The impact of climate change on herbivorous insects can have far-reaching consequences for ecosystem processes. However, experiments investigating the combined effects of multiple climate change drivers on herbivorous insects are scarce. We independently manipulated three climate change drivers (CO......, nitrogen, and water content. Overall, drought was the most important factor for this insect herbivore. Our study shows that weight and survival of insect herbivores may decline under future climate. The complexity of insect herbivore responses increases with the number of combined climate change drivers....

  2. Post-irradiation protection from infestation by insect resistant packaging

    International Nuclear Information System (INIS)

    Foods that are susceptible to insect infestation can be irradiated to destroy the infestation; however, the food must be kept insect-free until consumed, or it must be disinfested again, perhaps repeatedly. Insect-resistant packages can be used to prevent infestation, but certain requirements must be fulfilled before a package can be made insect resistant. These include the use of insect tight construction and packaging materials that resist boring insects. The relative insect resistance of various packages and packaging materials is discussed, as are behaviour traits such as egressive boring that enables insects to escape from packages, and the ability of insects to climb on to various packaging materials. Successful and unsuccessful attempts to make various types of package insect resistant are discussed, as are factors that must be considered in the selection or development of insect resistant packages for radiation-disinfested foods. The latter factors include the biological and physical environments, the length of storage periods, the stress on packages during shipment, the types of storage facility, the governmental regulations, health requirements, etc. (author). 21 refs

  3. Emerging strategies for RNA interference (RNAi) applications in insects.

    Science.gov (United States)

    Nandety, Raja Sekhar; Kuo, Yen-Wen; Nouri, Shahideh; Falk, Bryce W

    2015-01-01

    RNA interference (RNAi) in insects is a gene regulatory process that also plays a vital role in the maintenance and in the regulation of host defenses against invading viruses. Small RNAs determine the specificity of the RNAi through precise recognition of their targets. These small RNAs in insects comprise small interfering RNAs (siRNAs), micro RNAs (miRNAs) and Piwi interacting RNAs (piRNAs) of various lengths. In this review, we have explored different forms of the RNAi inducers that are presently in use, and their applications for an effective and efficient fundamental and practical RNAi research with insects. Further, we reviewed trends in next generation sequencing (NGS) technologies and their importance for insect RNAi, including the identification of novel insect targets as well as insect viruses. Here we also describe a rapidly emerging trend of using plant viruses to deliver the RNAi inducer molecules into insects for an efficient RNAi response.

  4. Ionizing radiation for insect control in grain and grain products

    International Nuclear Information System (INIS)

    A technical review summarizes and discusses information on various aspects of the use of ionizing radiation for the control of insect infestation in grains and grain products. Topics include: the effects of ionizing radiation on insects infesting stored-grain products; the 2 main types of irradiators (electron accelerators; radioisotopes (e.g.: Co-60; Cs-137); dosimetry systems and methodology; variations in radiation resistance by stored-product pests; the proper selection of radiation dose; the effects of combining various treatments (temperature, infrared/microwave radiation, hypoxia, chemicals) with ionizing radiation; sublethal radiation for controlling bulk grain insects; the feeding capacity of irradiated insects; the susceptibility of insecticide-resistant insects to ionizing radiation; and the possible resistance of insects to ionizing radiation. Practical aspects of removing insects from irradiated grain also are discussed

  5. Insects in the human food chain: global status and opportunities

    DEFF Research Database (Denmark)

    Halloran, Afton Marina Szasz; Muenke, Christopher; Vantomme, Paul;

    2014-01-01

    Insects are part of the traditional diets of approximately 2 billion people worldwide. Insects can contribute to food security and be a part of the solution to protein shortages, given their high nutritional value, low emissions of greenhouse gases, low requirements for land and water, and the high...... efficiency at which they can convert feed into food. This article outlines the potential of insects as a food for humans as well as a feedstock for animals and fish. The majority of insects consumed in developing countries today are harvested in nature from wild populations. In Western countries, the disgust...... factor in considering insects as food, combined currently with their limited availability on the market, and a lack of regulations governing insects as food and feed, are major barriers for their further expansion. However, the biggest opportunity may well lie in the production of insect biomass...

  6. Mode of action of Bacillus thuringiensis Cry and Cyt toxins and their potential for insect control.

    Science.gov (United States)

    Bravo, Alejandra; Gill, Sarjeet S; Soberón, Mario

    2007-03-15

    Bacillus thuringiensis Crystal (Cry) and Cytolitic (Cyt) protein families are a diverse group of proteins with activity against insects of different orders--Lepidoptera, Coleoptera, Diptera and also against other invertebrates such as nematodes. Their primary action is to lyse midgut epithelial cells by inserting into the target membrane and forming pores. Among this group of proteins, members of the 3-Domain Cry family are used worldwide for insect control, and their mode of action has been characterized in some detail. Phylogenetic analyses established that the diversity of the 3-Domain Cry family evolved by the independent evolution of the three domains and by swapping of domain III among toxins. Like other pore-forming toxins (PFT) that affect mammals, Cry toxins interact with specific receptors located on the host cell surface and are activated by host proteases following receptor binding resulting in the formation of a pre-pore oligomeric structure that is insertion competent. In contrast, Cyt toxins directly interact with membrane lipids and insert into the membrane. Recent evidence suggests that Cyt synergize or overcome resistance to mosquitocidal-Cry proteins by functioning as a Cry-membrane bound receptor. In this review we summarize recent findings on the mode of action of Cry and Cyt toxins, and compare them to the mode of action of other bacterial PFT. Also, we discuss their use in the control of agricultural insect pests and insect vectors of human diseases. PMID:17198720

  7. Detection methods for irradiated mites and insects

    International Nuclear Information System (INIS)

    Results of the study on the following tests for separation of irradiated pests from untreated ones are reported: (a) test for identification of irradiated mites (Acaridae) based on lack of fecundity of treated females; (b) test for identification of irradiated beetles based on their locomotor activity; (c) test for identification of irradiated pests based on electron spin resonance (ESR) signal derived from treated insects; (d) test for identification of irradiated pests based on changes in the midgut induced by gamma radiation; and (e) test for identification of irradiated pests based on the alterations in total proteins of treated adults. Of these detection methods, only the test based on the pathological changes induced by irradiation in the insect midgut may identify consistently either irradiated larvae or adults. This test is simple and convenient when a rapid processing technique for dehydrating and embedding the midgut is used. (author)

  8. Velocity correlations in laboratory insect swarms

    Science.gov (United States)

    Ni, R.; Ouellette, N. T.

    2015-12-01

    In contrast to animal groups such as bird flocks or migratory herds that display net, directed motion, insect swarms do not possess global order. Without such order, it is difficult to define and characterize the transition to collective behavior in swarms; nevertheless, visual observation of swarms strongly suggests that swarming insects do behave collectively. It has recently been suggested that correlation rather than order is the hallmark of emergent collective behavior. Here, we report measurements of spatial velocity correlation functions in laboratory mating swarms of the non-biting midge Chironomus riparius. Although we find some correlation at short distances, our swarms are in general only weakly correlated, in contrast to what has been observed in field studies. Our results hint at the potentially important role of environmental conditions on collective behavior, and suggest that general indicators of the collective nature of swarming are still needed.

  9. Insects as vectors: systematics and biology.

    Science.gov (United States)

    Rodhain, F

    2015-04-01

    Among the many complex relationships between insects and microorganisms such as viruses, bacteria and parasites, some have resulted in the establishment of biological systems within which the insects act as a biological vector for infectious agents. It is therefore advisable to understand the identity and biology of these vectors in depth, in order to define procedures for epidemiological surveillance and anti-vector control. The following are successively reviewed in this article: Anoplura (lice), Siphonaptera (fleas), Heteroptera (bugs: Cimicidae, Triatoma, Belostomatidae), Psychodidae (sandflies), Simuliidae (black flies), Ceratopogonidae (biting midges), Culicidae (mosquitoes), Tabanidae (horseflies) and Muscidae (tsetse flies, stable flies and pupipara). The authors provide a rapid overview of the morphology, systematics, development cycle and bio-ecology of each of these groups of vectors. Finally, their medical and veterinary importance is briefly reviewed.

  10. Remote radio control of insect flight

    Directory of Open Access Journals (Sweden)

    Hirotaka Sato

    2009-10-01

    Full Text Available We demonstrated the remote control of insects in free flight via an implantable radio-equipped miniature neural stimulating system. The pronotum mounted system consisted of neural stimulators, muscular stimulators, a radio transceiver-equipped microcontroller and a microbattery. Flight initiation, cessation and elevation control were accomplished through neural stimulus of the brain which elicited, suppressed or modulated wing oscillation. Turns were triggered through the direct muscular stimulus of either of the basalar muscles. We characterized the response times, success rates, and free-flight trajectories elicited by our neural control systems in remotely-controlled beetles. We believe this type of technology will open the door to in-flight perturbation and recording of insect flight responses.

  11. Managing social insects of urban importance.

    Science.gov (United States)

    Rust, Michael K; Su, Nan-Yao

    2012-01-01

    Social insects have a tremendous economic and social impact on urban communities. The rapid urbanization of the world has dramatically increased the incidence of urban pests. Human commerce has resulted in the spread of urban invasive species worldwide such that various species are now common to many major urban centers. We aim to highlight those social behaviors that can be exploited to control these pests with the minimal use of pesticides. Their cryptic behavior often prohibits the direct treatment of colonies. However, foraging and recruitment are essential aspects of their social behavior and expose workers to traps, baits, and pesticide applications. The advent of new chemistries has revolutionized the pest management strategies used to control them. In recent years, there has been an increased environmental awareness, especially in the urban community. Advances in molecular and microbial agents promise additional tools in developing integrated pest management programs against social insects. PMID:21942844

  12. Insects as vectors: systematics and biology.

    Science.gov (United States)

    Rodhain, F

    2015-04-01

    Among the many complex relationships between insects and microorganisms such as viruses, bacteria and parasites, some have resulted in the establishment of biological systems within which the insects act as a biological vector for infectious agents. It is therefore advisable to understand the identity and biology of these vectors in depth, in order to define procedures for epidemiological surveillance and anti-vector control. The following are successively reviewed in this article: Anoplura (lice), Siphonaptera (fleas), Heteroptera (bugs: Cimicidae, Triatoma, Belostomatidae), Psychodidae (sandflies), Simuliidae (black flies), Ceratopogonidae (biting midges), Culicidae (mosquitoes), Tabanidae (horseflies) and Muscidae (tsetse flies, stable flies and pupipara). The authors provide a rapid overview of the morphology, systematics, development cycle and bio-ecology of each of these groups of vectors. Finally, their medical and veterinary importance is briefly reviewed. PMID:26470450

  13. Insect Pathogenic Bacteria in Integrated Pest Management

    OpenAIRE

    Luca Ruiu

    2015-01-01

    The scientific community working in the field of insect pathology is experiencing an increasing academic and industrial interest in the discovery and development of new bioinsecticides as environmentally friendly pest control tools to be integrated, in combination or rotation, with chemicals in pest management programs. In this scientific context, market data report a significant growth of the biopesticide segment. Acquisition of new technologies by multinational Ag-tech companies is the cent...

  14. Sterile insect technique in codling moth control

    International Nuclear Information System (INIS)

    Exposure of mature pupae or adult codling moths, Cydia pomonella (L.), to 30-40 krad of gamma radiation induces a high level of sterility in the male and complete sterility in the female without seriously affecting behaviour except for sperm competitiveness which is drastically reduced. Substerilizing doses (below about 25 krad) have very little adverse effect and induces higher level of sterility in the F1 male than in the irradiated male parent. The most satisfactory method of measuring the population density of native moths is by examining fruit for larval exit holes. Population increase per generation depends largely on evening temperatures during the moth's reproductive period. The codling moth is a sedentary species, and its distribution is very uneven in commercial orchards. Neglected host trees must be sprayed or destroyed to avoid reinfestation of sterile insect release orchards with immigrant moths. Laboratory-reared moths may be marked externally with fluorescent powders or internally with calco oil red without adverse effects. Mass rearing is still unreliable and expensive, and prolonged colonization affects the insects' behaviour. Successful codling moth suppression was achieved in North America and/or Europe by release of sterile males, sterile females or sterile mixed sexes; by substerile males; and by F1 male progeny (released as diapausing larvae) of substerile males X untreated females. Arthropod predators and parasites held aphids and spider mites at noninjurious levels in most insect release orchards, but leafrollers eventually built up to damaging numbers. The sterile insect technique for commercial control of the codling moth is not feasible at this time because of high costs. (author)

  15. Potent limonoid insect antifeedant from Melia azedarach.

    Science.gov (United States)

    Carpinella, Cecilia; Ferrayoli, Carlos; Valladares, Graciela; Defago, Maria; Palacios, Sara

    2002-08-01

    Systematic fractionation of a fruit extract from Argentine Melia azedarach L., which was monitored by an insect antifeedant bioassay, led to the isolation of meliartenin, a limonoid antifeedant, which existed as a mixture of two interchangeable isomers. At 4 microg/cm2 and 1 microg/cm2, the isomeric mixture was as active as azadirachtin in strongly inhibiting the larval feeding of Epilachna paenulata Germ. (Coleoptera: Coccinellidae) and the polyphagous pest, Spodoptera eridania (Lepidoptera: Noctuidae), respectively. PMID:12353636

  16. Insects as food - something for the future?

    OpenAIRE

    Jansson, Anna; Berggren, Åsa

    2015-01-01

    Increased world population, greater pressure on the environment, increased use of land resources globally and increased demand for nutrients and non-renewable energy are predicted for coming decades. Livestock production accounts for 70% of all agricultural land use and, as the global demand for livestock products is expected to almost double by 2050, innovative production solutions are needed. Insect farming has been suggested as a good alternative to conventional livestock farming for futur...

  17. Exotic Forest Insects and Residential Property Values

    OpenAIRE

    Holmes, Thomas P.; Murphy, Elizabeth A; Kathleen P. Bell

    2006-01-01

    This paper presents a case study of the economic damages to homeowners in a northern New Jersey community due to an exotic forest insect--the hemlock woolly adelgid. Hedonic property value methods are used to estimate the effect of hemlock health on property values. A statistically significant relationship between hemlock health and residential property values is established. Moreover, there are some signs of spillover impacts from hemlock decline, as negative effects are realized on the parc...

  18. Climate Change Effects Overwintering of Insects

    DEFF Research Database (Denmark)

    Vukasinovic, Dragana

    Climate change is modifying winter conditions rapidly and predicting species’ reactions to global warming has been the “the holy grail” of climate sciences, especially for managed systems, like agro-ecosystems. Intuitively, increased winter temperatures should release insects from coldinduced...... of a rapid, contemporary evolution, optimal formeasuring species response under constant selection pressure, including organismal physiology.Thus, the methodological approach applied in this study, could prove a valuable tool for improving predictability of field population dynamics during climate change....

  19. Syntheses of Allelochemicals for Insect Control

    OpenAIRE

    Smitt, Olof

    2002-01-01

    This thesis describes the synthetic preparation of somecompounds, which can serve as chemical signals for use in thedevelopment of control methods for pest insects. The compoundssynthesised are of the isoprenoid type and of two kinds:carvone derivatives and germacranes. The derivatives of carvoneare based on modifications of this compound, by reactions ofeither its endocyclic or its exocyclic double bond. One type ofmodifications was accomplished by chemoselective additions ofthiophenol. The ...

  20. Minor lipophilic compounds in edible insects

    Directory of Open Access Journals (Sweden)

    Monika Sabolová

    2016-07-01

    Full Text Available Contemporary society is faced with the question how to ensure suffiecient nutrition (quantity and quality for rapidly growing population. One solution can be consumption of edible insect, which can have very good nutritional value (dietary energy, protein, fatty acids, fibers, dietary minerals and vitamins composition. Some edible insects species, which contains a relatively large amount of fat, can have a potential to be a „good" (interesting, new source of minor lipophilic compounds such as sterols (cholesterol and phytosterols and tocopherols in our diet. For this reason, the objective of this work was to characterize the sterols and tocopherols composition of fat from larvae of edible insect Zophobas morio L. and Tenebrio mollitor L. Cholesterol and three phytosterols (campesterol, stigmasterol and β-sitosterol were reliably identified and quantified after hot saponification and derivatization by GC-MS. Other steroid compounds, including 5,6-trans-cholecalciferol were identified only according to the NIST library. Cholesterol was the predominant sterol in all analysed samples. Both types of larvae also contained high amount of phytosterols. Different region of origin had a no significant impact on sterols composition, while the effect of beetle genus was crucial. Tocopherols were analysed by reverse phase HPLC coupled with amperometric detection. Tocopherols content in mealworm larvae was lower than content in edible oils, but important from the nutritional point of view. Change of tocopherols composition was not observed during the storage under different conditions. Larvae of edible insect can be a potential good dietary source of cholesterol, but also vitamin D3 isomers, phytosterols and tocopherols.  

  1. Radioisotope Study of Tegumentary Pigmentation in Insects

    International Nuclear Information System (INIS)

    The nature of insect cuticle, which is made up in large part of scleroproteins, calls for the use of labelled isotopes to obtain answers to certain questions regarding pigmentation. The following method, which has the advantage of being quick and easy to apply, has been developed. The labelled substance chosen is injected into the animal at various phases of its skin-shedding cycle: before secretion of the cuticular proteins, i. e. when the cuticle is at rest; at the time these proteins are deposited; and, lastly, at the time their sclerification begins. After a suitable interval the cuticle is removed, suitably treated, and subjected to full autoradiography. Photographic comparison of the results then indicates whether or not the substance chosen has been used for any formation of pigment, due account being taken of prior chemical processes involving the substance. The findings presented in the paper relate to three labelled substances: two carbon-14 amino-acids - tyrosine and tryptophane - and inorganic sulphur-35 in the form of sodium sulphate. It has thus been possible to give direct proof of the origin of variously-coloured cuticular pigments and to discuss the role of tryptophane and sulphur in forming pigments in insect integument. All cuticular pigments spring from the metabolism of tyrosine, thus confirming the term ''melanic'' hitherto applied to them without direct proof. Tryptophane, exceptionally integrated in the cuticle, is the substratum of the ommochromic red and black pigments in the hypodermis. Inorganic sulphur plays no regular specific role in the formation of cuticular pigments, contrary to what has been suggested by various hypotheses on the role of the sulpbydryl group. From the standpoint of comparative biochemistry, the melanins appear to be purely cuticular among insects, granular melanins being confined to the vertebrates. Dark hypodermic granules in insects are ommochromic, derived from tryptophane, and not melanic. (author)

  2. Insect and Pest Control Newsletter. No. 46

    International Nuclear Information System (INIS)

    This newsletter lists the FAO/IAEA meetings in the field of pest control held between September 1990 and February 1991 and provides very brief summaries of their contents. It also features a special report on the New World Screwworm in North Africa. An eradication programme, organized by the IAEA and the FAO and based on the sterile insect technique, was implemented, and as a result it is expected that the area will be declared free of the pest during autumn 1991

  3. Phase Coherence Analysis of Insect Flight

    CERN Document Server

    Shchekinova, E Y

    2009-01-01

    During insect flight a high--frequency wing oscillatory motion is generated. Here we present analysis of kinematic data of tethered Drosophila melanogaster flight. For a reliable detection of specific regimes of frequency variation we propose phase coherence method. The approach is generic and can be applied to nonstationary biological signals that feature multi- scale frequency variations. Our analysis reveals existence of distinct oscillatory modes.

  4. Insect and pest control newsletter. No. 58

    International Nuclear Information System (INIS)

    This issue of the Newsletter announces the development of a draft international standard to facilitate the transboundary shipment of sterile insects stands out. This was developed in response to requests from Member States and the private sector for regulation of the shipping of sterile insects. The draft standard will be considered, reviewed and hopefully endorsed over the next years by the Interim Commission on Phytosanitary Measures (ICPM), the governing body of the International Plant protection Convention (IPPC). Also of significance are the Fruit Fly Trapping Guidelines that have been developed to support the harmonization of monitoring procedures for these pest insects in view of the increasing fruit fly related transboundary interactions resulting from the rapidly growing trade in agricultural commodities, as well as travel, transport and tourism. An upcoming event also in the normative area is an FAO/IAEA Expert Meeting on 'Risk Assessment of Transgenic Arthropods' to be held at FAO, Rome from 8-12 April, 2002. The objective of the meeting are to a) assess current status of transgenesis in pest arthropods; b) to assess biosafety concerns for transgenic arthropod release; c) to provide guidance for future risk assessment protocols for case by case analysis; and d) to assess the possibility of establishing a working group under IPPC for setting guidelines for development and use of transgenic insect technology. An important event at the end of 2001 was the Resolution on the Pan African Tsetse and Trypanosomosis Eradication Campaign (PATTEC) adopted by the FAO Conference held in Rome, 2-13 November 2001 (for the full text of the resolution see page 39).. The resolution acknowledges the severity of the trypanosomosis problem in sub-Saharan Africa, and the potential benefits of tsetse elimination, and calls upon affected member nations to include tsetse eradication in their Poverty Reduction Strategy Papers and for the FAO to support them in their efforts to

  5. Dynamic flight stability of hovering insects

    Institute of Scientific and Technical Information of China (English)

    Mao Sun; Jikang Wang; Yan Xiong

    2007-01-01

    The equations of motion of an insect with flapping wings are derived and then simplified to that of a flying body using the "rigid body" assumption. On the basis of the simplified equations of motion, the longitudinal dynamic flight stability of four insects (hoverfly, cranefly, dronefly and hawkmoth) in hovering flight is studied (the mass of the insects ranging from 11 to 1,648 mg and wingbeat frequency from 26 to 157Hz). The method of computational fluid dynamics is used to compute the aerodynamic derivatives and the techniques of eigenvalue and eigenvector analysis are used to solve the equations of motion. The validity of the "rigid body" assumption is tested and how differencesin size and wing kinematics influence the applicability of the "rigid body" assumption is investigated. The primary findings are: (1) For insects considered in the present study and those with relatively high wingbeat frequency (hover-fly, drone fly and bumblebee), the "rigid body" assumptionis reasonable, and for those with relatively low wingbeatfrequency (cranefly and howkmoth), the applicability of the"rigid body" assumption is questionable. (2) The same three natural modes of motion as those reported recently for a bumblebee are identified, i.e., one unstable oscillatory mode,one stable fast subsidence mode and one stable slow subsidence mode. (3) Approximate analytical expressions of the eigenvalues, which give physical insight into the genesis of the natural modes of motion, are derived. The expressions identify the speed derivative Mu (pitching moment produced by unit horizontal speed) as the primary source of the unstable oscillatory mode and the stable fast subsidence mode and Zw (vertical force produced by unit vertical speed) as the primary source of the stable slow subsidence mode.

  6. The risk of insecticides to pollinating insects

    OpenAIRE

    Connolly, Christopher N.

    2013-01-01

    A key new risk to our pollinators has been identified as exposure to neonicotinoid insecticides. These discoveries have refuelled the debate over whether or not the neonicotinoid insecticides should be banned and conflicting evidence is used in this battle. However, the issue is not black or white, but gray. It is not an issue of whether the neonicotinoids are toxic to insects or not. Clearly, all insecticides were designed and optimized for this attribute. The real question is, or at least s...

  7. BUSINESS PLAN FOR BOKE INSECT RESTAURANT

    OpenAIRE

    Nguyen, Duc Van

    2015-01-01

    The economy in Vietnam has been growing quite considerably since the past two decades. Different business fields have been developed very widely and strongly such as culinary industry particularly in Ho Chi Minh City, the largest city in Vietnam. Many restaurants with various styles and cuisines are being established and invested due to the increase of customers’ demand. However, there are some areas in this business field which have not been exploited recently, for example insect food, so bu...

  8. Insect Resistant Corn Event MIR 162

    OpenAIRE

    Directorate, Issued by Health Canada's Food

    2014-01-01

    Health Canada has notified Syngenta Seeds Canada Inc. that it has no objection to the sale of food derived from Insect Resistant Corn Event MIR 162. The Department conducted a comprehensive assessment of this corn event hybrid according to its Guidelines for the Safety Assessment of Novel Foods. These Guidelines are based upon internationally accepted principles for establishing the safety of foods with novel traits.

  9. Advantages and trends in managing insect pests

    International Nuclear Information System (INIS)

    Although many different insect control methods are currently in use, there has been a heavy reliance on conventional insecticides for more than forty years. Because of the development of insecticide resistance, the public concern about environmental and health risks, and the high cost of development, approvals for specific insecticide uses are now being removed at a faster rate than they are being replaced. Alternative insect management technologies will be required, and a strategy for their use should be selected based on the characteristics of the technology to be used and the pest involved. Most insect problems can best be dealt with by a pest management programme that includes integration of two or more suppression methods with the aid of a strong population dynamics knowledge base, decision support systems, economic analyses and environmental assessments. Although trends cannot be predicted with certainty, the market for conventional insecticides probably will decline and the market for biologically based products probably will increase. Thus, an increased number of biological suppression methods will probably be available in the future. Additional emphasis should also be placed on the development of non-product oriented, biologically based control methods. 43 refs, 1 fig., 2 tabs

  10. Genitalia-associated microbes in insects.

    Science.gov (United States)

    Otti, Oliver

    2015-03-01

    In sexual reproduction different types of symbiotic relationships between insects and microbes have become established. For example, some bacteria have evolved almost exclusive vertical transmission and even define the compatibility of insect mating partners. Many strictly sexually transmitted diseases have also been described in insects. Apart from such rather specific relationships the role of opportunistic infections in the reproductive process has been widely neglected. Opportunistic microbes transmitted passively during mating might impose an energetic cost, as the immune system will need to be alert and will use resources to fight potential intruders. Through mating wounds and contaminated reproductive organs opportunistic microbes might be transferred to mating partners and even enter the body cavity. Females as the "receiving" sex are particularly likely to have evolved adaptations to avoid or reduce opportunistic infections. Males of several species show highly complex seminal fluids, which as well as containing components that influence a males' fertilization success, also possess antimicrobial substances. The role of antimicrobials in the reproductive process is not well understood. Some evidence hints at the protection of sperm against microbes, indicating a role for natural selection in shaping the evolution of reproductive traits. By highlighting the potential importance of microbes in sexual selection and their role in reproduction in general I will make a case for studies in sexual selection, especially the ones investigating postcopulatory processes, that should incorporate environmental, as well as genotypic variation, in reproductive traits.

  11. Insect habitat management in pasture systems

    Science.gov (United States)

    Martin, P. B.

    1983-01-01

    Two important habitat management strategies in pasture systems involve controlled burning and effective grazing manipulation schemes to maintain native climax grassland vegetation These climax grasslands have historically suffered less insect pest pressure than imported systems However, these types of grasslands are difficult to reestablish after relatively severe disruption by man Also, the proper diversity and stability is difficult to capture in developing imported systems. Imported pastures can exhibit substantial yields per land unit but are often composed of vegetation that rapidly mines nutrients stored by the native vegetation, and often need considerable inputs of fossil fuel, manufactured fertilizers and pesticides, because they are or become very susceptible to pestiferous insects. Habitat manipulation efforts can be effective in regulating forage pest populations below economic levels in imported pasture systems Such efforts include: 1) land use (coupled with plant diversity, grazing, and harvest manipulations), 2) sanitation (including controlled burning), 3) planting dates and harvest times (including grazing manipulations), 4) tillage methods, 5) fertilization, 6) trap crops, 7) water management, and 8) fire management for insect pest suppression and augmentation of natural enemies.

  12. Insect gas exchange patterns: a phylogenetic perspective.

    Science.gov (United States)

    Marais, Elrike; Klok, C Jaco; Terblanche, John S; Chown, Steven L

    2005-12-01

    Most investigations of insect gas exchange patterns and the hypotheses proposed to account for their evolution have been based either on small-scale, manipulative experiments, or comparisons of a few closely related species. Despite their potential utility, no explicit, phylogeny-based, broad-scale comparative studies of the evolution of gas exchange in insects have been undertaken. This may be due partly to the preponderance of information for the endopterygotes, and its scarcity for the apterygotes and exopterygotes. Here we undertake such a broad-scale study. Information on gas exchange patterns for the large majority of insects examined to date (eight orders, 99 species) is compiled, and new information on 19 exemplar species from a further ten orders, not previously represented in the literature (Archaeognatha, Zygentoma, Ephemeroptera, Odonata, Mantodea, Mantophasmatodea, Phasmatodea, Dermaptera, Neuroptera, Trichoptera), is provided. These data are then used in a formal, phylogeny-based parsimony analysis of the evolution of gas exchange patterns at the order level. Cyclic gas exchange is likely to be the ancestral gas exchange pattern at rest (recognizing that active individuals typically show continuous gas exchange), and discontinuous gas exchange probably originated independently a minimum of five times in the Insecta. PMID:16339869

  13. Ecological interaction between insect pests, climatic factors and plant traits on abundance of beneficial insects in paddy field

    Directory of Open Access Journals (Sweden)

    Norazliza, R.

    2016-04-01

    Full Text Available The presences of beneficial insects in the paddy field are very important for the ecological systems of paddy field as those insects could help managing the population of the pests. Hence, it will reduce the dependence on pesticides usage to combat the population of insect pests. This study was aimed to study on ecological interaction between environmental factors such as insect pests, plant height, rainfall, temperature and humidity with abundance of beneficial insects in paddy field of Sungai Burong, Tanjung Karang, Selangor for two seasons of paddy planting. Low number of insects composition were recorded in paddy field at Sungai Burong during the vegetative phase and highest during the reproductive and maturity phases for two seasons of paddy planting. The trend of mean composition of insects were gradually increasing from vegetative to maturity phases while, the ecological interaction between insect pests, climatic factors and plant traits were acceptable as good predictor for all beneficial insects collected in this study namely Zygoptera, Gerridae, Coccinellidae and Staphylinidae except for Anisoptera. Therefore, consideration on several stated factors by maintaining or conserving ecology and controlling practices in good manner in paddy field has high potential and more reliable to control insect pests effectively using beneficial insects.

  14. Applying the sterile insect technique to the control of insect pests

    International Nuclear Information System (INIS)

    The sterile insect technique involves the mass-rearing of insects, which are sterilized by gamma rays from a 60Co source before being released in a controlled fashion into nature. Matings between the sterile insects released and native insects produce no progeny, and so if enough of these matings occur the pest population can be controlled or even eradicated. A modification of the technique, especially suitable for the suppression of the moths and butterflies, is called the F, or inherited sterility method. In this, lower radiation doses are used such that the released males are only partially sterile (30-60%) and the females are fully sterile. When released males mate with native females some progeny are produced, but they are completely sterile. Thus, full expression of the sterility is delayed by one generation. This article describes the use of the sterile insect technique in controlling the screwworm fly, the tsetse fly, the medfly, the pink bollworm and the melon fly, and of the F1 sterility method in the eradication of local gypsy moth infestations. 18 refs, 5 figs, 1 tab

  15. Monitoring the agricultural landscape for insect resistance

    Science.gov (United States)

    Casas, Joseph; Glaser, J. A.; Copenhaver, Ken

    Farmers in 25 countries on six continents are using plant biotechnology to solve difficult crop production challenges and conserve the environment. In fact, 13.3 million farmers, which include 90 percent of the farming in developing countries, choose to plant biotech crops. Over the past decade, farmers increased area planted in genetically modified (GM) crops by more than 10 percent each year, thus increasing their farm income by more than 44 billion US dollars (1996-2007), and achieved economic, environmental and social benefits in crops such as soybeans, canola, corn and cotton. To date, total acres of biotech crops harvested exceed more than 2 billion with a proven 13-year history of safe use. Over the next decade, expanded adoption combined with current research on 57 crops in 63 countries will broaden the advantages of genetically modified foods for growers, consumers and the environment. Genetically modified (GM) crops with the ability to produce toxins lethal to specific insect pests are covering a larger percentage of the agricultural landscape every year. The United States department of Agriculture (USDA) estimated that 63 percent of corn and 65 percent of cotton contained these specific genetic traits in 2009. The toxins could protect billions of dollars of loss from insect damage for crops valued at greater than 165 billion US dollars in 2008. The stable and efficient production of these crops has taken on even more importance in recent years with their use, not only as a food source, but now also a source of fuel. It is in the best interest of the United States Environmental Protection Agency (USEPA) to ensure the continued efficacy of toxin producing GM crops as their use reduces pesticides harmful to humans and animals. However, population genetics models have indicated the risk of insect pests developing resistance to these toxins if a high percentage of acreage is grown in these crops. The USEPA is developing methods to monitor the agricultural

  16. Insect cuticle, an in vivo model of protein trafficking.

    Science.gov (United States)

    Csikós, G; Molnár, K; Borhegyi, N H; Talián, G C; Sass, M

    1999-07-01

    In the course of this study more than 20 proteins have been isolated from the larval cuticle of Manduca sexta. Synthesis, secretion, transport and accumulation of four particular proteins, representative members of four characteristic groups, were followed during metamorphosis by immunoblot and immuncytochemical methods and are described in detail in this paper. We established that only some of the proteins of the soft cuticle of Lepidopteran larvae are synthesized in epidermal cells at the beginning of the larval stages and are digested during the moulting period (MsCP29). Other proteins (MsCP30/11) are secreted into the cuticle by the epidermal cells in different forms during various developmental stages. Some proteins are secreted apically during the feeding period, but before ecdysis they are then taken up by epidermal cells and transported in a basolateral direction back into the hemolymph and saved in an immunologically intact form by the fat body cells (MsCP12.3). Some cuticle proteins have a non-epidermal origin. They are transported from the hemolymph into the cuticle. Before and during ecdysis these molecules reappear in the hemolymph and are detectable again in the pupal cuticle (MsCP78). Our data prove that the cuticle is not a non-living part of the insect body: it is not only an inert, protective armor, but maintains a continuous and dynamic metabolic connection with the other organs of the organism. PMID:10362541

  17. Genomics of adaptation to host-plants in herbivorous insects.

    Science.gov (United States)

    Simon, Jean-Christophe; d'Alençon, Emmanuelle; Guy, Endrick; Jacquin-Joly, Emmanuelle; Jaquiéry, Julie; Nouhaud, Pierre; Peccoud, Jean; Sugio, Akiko; Streiff, Réjane

    2015-11-01

    Herbivorous insects represent the most species-rich lineages of metazoans. The high rate of diversification in herbivorous insects is thought to result from their specialization to distinct host-plants, which creates conditions favorable for the build-up of reproductive isolation and speciation. These conditions rely on constraints against the optimal use of a wide range of plant species, as each must constitute a viable food resource, oviposition site and mating site for an insect. Utilization of plants involves many essential traits of herbivorous insects, as they locate and select their hosts, overcome their defenses and acquire nutrients while avoiding intoxication. Although advances in understanding insect-plant molecular interactions have been limited by the complexity of insect traits involved in host use and the lack of genomic resources and functional tools, recent studies at the molecular level, combined with large-scale genomics studies at population and species levels, are revealing the genetic underpinning of plant specialization and adaptive divergence in non-model insect herbivores. Here, we review the recent advances in the genomics of plant adaptation in hemipterans and lepidopterans, two major insect orders, each of which includes a large number of crop pests. We focus on how genomics and post-genomics have improved our understanding of the mechanisms involved in insect-plant interactions by reviewing recent molecular discoveries in sensing, feeding, digesting and detoxifying strategies. We also present the outcomes of large-scale genomics approaches aimed at identifying loci potentially involved in plant adaptation in these insects.

  18. Glucosinolate breakdown products as insect fumigants and their effect on carbon dioxide emission of insects

    Directory of Open Access Journals (Sweden)

    Coats Joel R

    2002-03-01

    Full Text Available Abstract Background Glucosinolate breakdown products are volatile, therefore good candidates for insect fumigants. However, although they are insecticidal, the mode of action of such natural products is not clear. We studied the insecticidal effect of these compounds as fumigants, and monitored the production of carbon dioxide by the insects as a probe to the understanding of their mode of action. Results The fumigation 24-h LC50 against the house fly (Musca domestica L. of allyl thiocyanate, allyl isothiocyanate, allyl cyanide, and l-cyano-2-hydroxy-3-butene was 0.1, 0.13, 3.66, and 6.2 μg cm-3, respectively; they were 0.55, 1.57, 2.8, and > 19.60 μg cm-3, respectively, against the lesser grain borer (Rhyzopertha dominica Fabricius. The fumigation toxicity of some of the glucosinolate products was very close to or better than that of the commercial insect fumigants such as chloropicrin (LC50: 0.08 and 1.3 μg cm-3 against M. domestica and R. dominica, respectively and dichlorovos (LC50: -3 against M. domestica and R. dominica, respectively in our laboratory tests. Significantly increased CO2 expiration was found in insects exposed to the vapor of allyl isothiocyanate, allyl thiocyanate and allyl isocyanate. Allyl isothiocyanate was also found to increase the CO2 expiration of the American cockroach (Periplaneta americana L.. Conclusions Glucosinolate breakdown products have potential as biodegradable and safe insect fumigants. They may act on the insect respiratory system in their mode of action.

  19. Insect-specific viruses detected in laboratory mosquito colonies and their potential implications for experiments evaluating arbovirus vector competence.

    Science.gov (United States)

    Bolling, Bethany G; Vasilakis, Nikos; Guzman, Hilda; Widen, Steven G; Wood, Thomas G; Popov, Vsevolod L; Thangamani, Saravanan; Tesh, Robert B

    2015-02-01

    Recently, there has been a dramatic increase in the detection and characterization of insect-specific viruses in field-collected mosquitoes. Evidence suggests that these viruses are ubiquitous in nature and that many are maintained by vertical transmission in mosquito populations. Some studies suggest that the presence of insect-specific viruses may inhibit replication of a super-infecting arbovirus, thus altering vector competence of the mosquito host. Accordingly, we screened our laboratory mosquito colonies for insect-specific viruses. Pools of colony mosquitoes were homogenized and inoculated into cultures of Aedes albopictus (C6/36) cells. The infected cells were examined by electron microscopy and deep sequencing was performed on RNA extracts. Electron micrograph images indicated the presence of three different viruses in three of our laboratory mosquito colonies. Potential implications of these findings for vector competence studies are discussed.

  20. Identification of irradiated insects: changes in the midgut of the confused flour beetle, Tribolium confusum Duv., induced by gamma radiation

    International Nuclear Information System (INIS)

    The radiation doses applied for quarantine treatment does not generally cause immediate death of insects and mites. Alive pests may be present in the agricultural commodities for several days. This can be a disadvantage if the product is for immediate export and there is a nil insect requirement. A simple test is needed to ensure the quarantine personnel that a pest of quarantine importance has been irradiated and it does not pose a quarantine risk. Development of a practical technique for identification of irradiated pests was recommended by the ICGFI Task Force Meeting on Irradiation as Quarantine Treatment. The midgut, metabolically very active tissue, is the main site for digestion and absorption of the products of digestion. The old epithelium is replaced by new cells produced by the regenerative nidi. Regenerative cells are very sensitive to radiation. Its damage results in loss of the midgut epithelium in irradiated insects. The following changes in the midgut structure of the confused flour beetle were observed: 1. destruction of the regenerative nidi; 2. elongation and enlargement of epithelial cells; 3. vacuolization of the epithelial cells; 4. fading of cells boundaries in the epithelium; 5. damage of the nuclei (chromatin grains scattered throughout the cytoplasm of epithelial cells); 6. loss of the brush border; 7. disintegration and further loss of epithelium. The most expressed effect of the irradiation treatment was the destruction of regenerative cells of the midgut. Their destruction prevented the replacement of the secretory cells of the epithelium. As a result the epithelium disappeared and the gut lumen enlarged. Causes other than ionizing radiation resulting in disintegration of the midgut epithelium of insects are unknown. Since the degenerative changes in the midgut are positively correlated with both dose and time elapsed after irradiation exposure, a pathological syndrome of irradiation effects on the midgut may be used for a rapid and