Science.gov

Sample records for genetically engineered animals

  1. Commercialising genetically engineered animal biomedical products.

    PubMed

    Sullivan, Eddie J; Pommer, Jerry; Robl, James M

    2008-01-01

    Research over the past two decades has increased the quality and quantity of tools available to produce genetically engineered animals. The number of potentially viable biomedical products from genetically engineered animals is increasing. However, moving from cutting-edge research to development and commercialisation of a biomedical product that is useful and wanted by the public has significant challenges. Even early stage development of genetically engineered animal applications requires consideration of many steps, including quality assurance and quality control, risk management, gap analysis, founder animal establishment, cell banking, sourcing of animals and animal-derived material, animal facilities, product collection facilities and processing facilities. These steps are complicated and expensive. Biomedical applications of genetically engineered animals have had some recent successes and many applications are well into development. As researchers consider applications for their findings, having a realistic understanding of the steps involved in the development and commercialisation of a product, produced in genetically engineered animals, is useful in determining the risk of genetic modification to the animal nu. the potential public benefit of the application. PMID:18154699

  2. Exogenous enzymes upgrade transgenesis and genetic engineering of farm animals.

    PubMed

    Bosch, Pablo; Forcato, Diego O; Alustiza, Fabrisio E; Alessio, Ana P; Fili, Alejandro E; Olmos Nicotra, María F; Liaudat, Ana C; Rodríguez, Nancy; Talluri, Thirumala R; Kues, Wilfried A

    2015-05-01

    Transgenic farm animals are attractive alternative mammalian models to rodents for the study of developmental, genetic, reproductive and disease-related biological questions, as well for the production of recombinant proteins, or the assessment of xenotransplants for human patients. Until recently, the ability to generate transgenic farm animals relied on methods of passive transgenesis. In recent years, significant improvements have been made to introduce and apply active techniques of transgenesis and genetic engineering in these species. These new approaches dramatically enhance the ease and speed with which livestock species can be genetically modified, and allow to performing precise genetic modifications. This paper provides a synopsis of enzyme-mediated genetic engineering in livestock species covering the early attempts employing naturally occurring DNA-modifying proteins to recent approaches working with tailored enzymatic systems. PMID:25636347

  3. Genetic Engineering

    ERIC Educational Resources Information Center

    Phillips, John

    1973-01-01

    Presents a review of genetic engineering, in which the genotypes of plants and animals (including human genotypes) may be manipulated for the benefit of the human species. Discusses associated problems and solutions and provides an extensive bibliography of literature relating to genetic engineering. (JR)

  4. Telos, conservation of welfare, and ethical issues in genetic engineering of animals.

    PubMed

    Rollin, Bernard E

    2015-01-01

    The most long-lived metaphysics or view of reality in the history of Western thought is Aristotle's teleology, which reigned for almost 2,000 years. Biology was expressed in terms of function or telos, and accorded perfectly with common sense. The rise of mechanistic, Newtonian science vanquished teleological explanations. Understanding and accommodating animal telos was essential to success in animal husbandry, which involved respect for telos, and was presuppositional to our "ancient contract" with domestic animals. Telos was further abandoned with the rise of industrial agriculture, which utilized "technological fixes" to force animal into environments they were unsuited for, while continuing to be productive. Loss of husbandry and respect for telos created major issues for farm animal welfare, and forced the creation of a new ethic demanding respect for telos. As genetic engineering developed, the notion arose of modifying animals to fit their environment in order to avoid animal suffering, rather than fitting them into congenial environments. Most people do not favor changing the animals, rather than changing the conditions under which they are reared. Aesthetic appreciation of husbandry and virtue ethics militate in favor of restoring husbandry, rather than radically changing animal teloi. One, however, does not morally wrong teloi by changing them-one can only wrong individuals. In biomedical research, we do indeed inflict major pain, suffering and disease on animals. And genetic engineering seems to augment our ability to create animals to model diseases, particularly more than 3,000 known human genetic diseases. The disease, known as Lesch-Nyhan's syndrome or HPRT deficiency, which causes self-mutilation and mental retardation, provides us with a real possibility for genetically creating "animal models" of this disease, animals doomed to a life of great and unalleviable suffering. This of course creates a major moral dilemma. Perhaps one can use the very genetic engineering which creates this dilemma to ablate consciousness in such animal models, thereby escaping a moral impasse. PMID:24496650

  5. Genetic Engineering of Dystroglycan in Animal Models of Muscular Dystrophy

    PubMed Central

    Sciandra, Francesca; Bigotti, Maria Giulia; Giardina, Bruno; Bozzi, Manuela; Brancaccio, Andrea

    2015-01-01

    In skeletal muscle, dystroglycan (DG) is the central component of the dystrophin-glycoprotein complex (DGC), a multimeric protein complex that ensures a strong mechanical link between the extracellular matrix and the cytoskeleton. Several muscular dystrophies arise from mutations hitting most of the components of the DGC. Mutations within the DG gene (DAG1) have been recently associated with two forms of muscular dystrophy, one displaying a milder and one a more severe phenotype. This review focuses specifically on the animal (murine and others) model systems that have been developed with the aim of directly engineering DAG1 in order to study the DG function in skeletal muscle as well as in other tissues. In the last years, conditional animal models overcoming the embryonic lethality of the DG knock-out in mouse have been generated and helped clarifying the crucial role of DG in skeletal muscle, while an increasing number of studies on knock-in mice are aimed at understanding the contribution of single amino acids to the stability of DG and to the possible development of muscular dystrophy. PMID:26380289

  6. Genetic Engineering of Dystroglycan in Animal Models of Muscular Dystrophy.

    PubMed

    Sciandra, Francesca; Bigotti, Maria Giulia; Giardina, Bruno; Bozzi, Manuela; Brancaccio, Andrea

    2015-01-01

    In skeletal muscle, dystroglycan (DG) is the central component of the dystrophin-glycoprotein complex (DGC), a multimeric protein complex that ensures a strong mechanical link between the extracellular matrix and the cytoskeleton. Several muscular dystrophies arise from mutations hitting most of the components of the DGC. Mutations within the DG gene (DAG1) have been recently associated with two forms of muscular dystrophy, one displaying a milder and one a more severe phenotype. This review focuses specifically on the animal (murine and others) model systems that have been developed with the aim of directly engineering DAG1 in order to study the DG function in skeletal muscle as well as in other tissues. In the last years, conditional animal models overcoming the embryonic lethality of the DG knock-out in mouse have been generated and helped clarifying the crucial role of DG in skeletal muscle, while an increasing number of studies on knock-in mice are aimed at understanding the contribution of single amino acids to the stability of DG and to the possible development of muscular dystrophy. PMID:26380289

  7. CRISPR/Cas9: a powerful genetic engineering tool for establishing large animal models of neurodegenerative diseases.

    PubMed

    Tu, Zhuchi; Yang, Weili; Yan, Sen; Guo, Xiangyu; Li, Xiao-Jiang

    2015-01-01

    Animal models are extremely valuable to help us understand the pathogenesis of neurodegenerative disorders and to find treatments for them. Since large animals are more like humans than rodents, they make good models to identify the important pathological events that may be seen in humans but not in small animals; large animals are also very important for validating effective treatments or confirming therapeutic targets. Due to the lack of embryonic stem cell lines from large animals, it has been difficult to use traditional gene targeting technology to establish large animal models of neurodegenerative diseases. Recently, CRISPR/Cas9 was used successfully to genetically modify genomes in various species. Here we discuss the use of CRISPR/Cas9 technology to establish large animal models that can more faithfully mimic human neurodegenerative diseases. PMID:26238861

  8. Myocardial and cerebral perfusion studies in animal models S65 In-vivo phenotyping of genetically engineered mouse models

    E-print Network

    of genetically engineered mouse models for amyotrophic lateral sclerosis is established by combining BT Endothelial Growth Factor gene(Vegf/ mice) develop motor neurodegeneration reminiscent for Amyotrophic Lateral Sclerosis (ALS)(1). Carmeliet et.al.(2)intercrossed mice expressing a SOD1G93A transgene (established mouse

  9. The new CRISPR-Cas system: RNA-guided genome engineering to efficiently produce any desired genetic alteration in animals.

    PubMed

    Seruggia, Davide; Montoliu, Lluis

    2014-10-01

    The CRISPR-Cas system is the newest targeted nuclease for genome engineering. In less than 1 year, the ease, robustness and efficiency of this method have facilitated an immense range of genetic modifications in most model organisms. Full and conditional gene knock-outs, knock-ins, large chromosomal deletions and subtle mutations can be obtained using combinations of clustered regularly interspaced short palindromic repeats (CRISPRs) and DNA donors. In addition, with CRISPR-Cas compounds, multiple genetic modifications can be introduced seamlessly in a single step. CRISPR-Cas not only brings genome engineering capacities to species such as rodents and livestock in which the existing toolbox was already large, but has also enabled precise genetic engineering of organisms with difficult-to-edit genomes such as zebrafish, and of technically challenging species such as non-human primates. The CRISPR-Cas system allows generation of targeted mutations in mice, even in laboratories with limited or no access to the complex, time-consuming standard technology using mouse embryonic stem cells. Here we summarize the distinct applications of CRISPR-Cas technology for obtaining a variety of genetic modifications in different model organisms, underlining their advantages and limitations relative to other genome editing nucleases. We will guide the reader through the many publications that have seen the light in the first year of CRISPR-Cas technology. PMID:25092533

  10. Engineering visualization utilizing advanced animation

    NASA Technical Reports Server (NTRS)

    Sabionski, Gunter R.; Robinson, Thomas L., Jr.

    1989-01-01

    Engineering visualization is the use of computer graphics to depict engineering analysis and simulation in visual form from project planning through documentation. Graphics displays let engineers see data represented dynamically which permits the quick evaluation of results. The current state of graphics hardware and software generally allows the creation of two types of 3D graphics. The use of animated video as an engineering visualization tool is presented. The engineering, animation, and videography aspects of animated video production are each discussed. Specific issues include the integration of staffing expertise, hardware, software, and the various production processes. A detailed explanation of the animation process reveals the capabilities of this unique engineering visualization method. Automation of animation and video production processes are covered and future directions are proposed.

  11. Genetically engineered foods

    MedlinePLUS

    ... corn, and soybeans have been genetically altered through biotechnology. Many more foods contain engineered ingredients and more ... FDA.gov. http://www.fda.gov/food/foodscienceresearch/biotechnology/ucm346030.htm. Last updated July 22, 2014. Accessed ...

  12. Genetic Engineering of a Mouse

    PubMed Central

    Jones, Dennis

    2011-01-01

    Genetic engineering is the process of modifying an organism’s genetic composition by adding foreign genes to produce desired traits or evaluate function. Dr. Jon W. Gordon and Sterling Professor Emeritus at Yale Dr. Frank H. Ruddle were pioneers in mammalian gene transfer research. Their research resulted in production of the first transgenic animals, which contained foreign DNA that was passed on to offspring. Transgenic mice have revolutionized biology, medicine, and biotechnology in the 21st century. In brief, this review revisits their creation of transgenic mice and discusses a few evolving applications of their transgenic technology used in biomedical research. PMID:21698043

  13. Genetically Engineered Cyanobacteria

    NASA Technical Reports Server (NTRS)

    Zhou, Ruanbao (Inventor); Gibbons, William (Inventor)

    2015-01-01

    The disclosed embodiments provide cyanobacteria spp. that have been genetically engineered to have increased production of carbon-based products of interest. These genetically engineered hosts efficiently convert carbon dioxide and light into carbon-based products of interest such as long chained hydrocarbons. Several constructs containing polynucleotides encoding enzymes active in the metabolic pathways of cyanobacteria are disclosed. In many instances, the cyanobacteria strains have been further genetically modified to optimize production of the carbon-based products of interest. The optimization includes both up-regulation and down-regulation of particular genes.

  14. Paper Genetic Engineering.

    ERIC Educational Resources Information Center

    MacClintic, Scott D.; Nelson, Genevieve M.

    Bacterial transformation is a commonly used technique in genetic engineering that involves transferring a gene of interest into a bacterial host so that the bacteria can be used to produce large quantities of the gene product. Although several kits are available for performing bacterial transformation in the classroom, students do not always…

  15. Selected Readings in Genetic Engineering

    ERIC Educational Resources Information Center

    Mertens, Thomas R.; Robinson, Sandra K.

    1973-01-01

    Describes different sources of readings for understanding issues and concepts of genetic engineering. Broad categories of reading materials are: concerns about genetic engineering; its background; procedures; and social, ethical and legal issues. References are listed. (PS)

  16. Safe genetically engineered plants

    NASA Astrophysics Data System (ADS)

    Rosellini, D.; Veronesi, F.

    2007-10-01

    The application of genetic engineering to plants has provided genetically modified plants (GMPs, or transgenic plants) that are cultivated worldwide on increasing areas. The most widespread GMPs are herbicide-resistant soybean and canola and insect-resistant corn and cotton. New GMPs that produce vaccines, pharmaceutical or industrial proteins, and fortified food are approaching the market. The techniques employed to introduce foreign genes into plants allow a quite good degree of predictability of the results, and their genome is minimally modified. However, some aspects of GMPs have raised concern: (a) control of the insertion site of the introduced DNA sequences into the plant genome and of its mutagenic effect; (b) presence of selectable marker genes conferring resistance to an antibiotic or an herbicide, linked to the useful gene; (c) insertion of undesired bacterial plasmid sequences; and (d) gene flow from transgenic plants to non-transgenic crops or wild plants. In response to public concerns, genetic engineering techniques are continuously being improved. Techniques to direct foreign gene integration into chosen genomic sites, to avoid the use of selectable genes or to remove them from the cultivated plants, to reduce the transfer of undesired bacterial sequences, and make use of alternative, safer selectable genes, are all fields of active research. In our laboratory, some of these new techniques are applied to alfalfa, an important forage plant. These emerging methods for plant genetic engineering are briefly reviewed in this work.

  17. Genetically Engineered Pig Models for Human Diseases

    PubMed Central

    Prather, Randall S.; Lorson, Monique; Ross, Jason W.; Whyte, Jeffrey J.; Walters, Eric

    2015-01-01

    Although pigs are used widely as models of human disease, their utility as models has been enhanced by genetic engineering. Initially, transgenes were added randomly to the genome, but with the application of homologous recombination, zinc finger nucleases, and transcription activator-like effector nuclease (TALEN) technologies, now most any genetic change that can be envisioned can be completed. To date these genetic modifications have resulted in animals that have the potential to provide new insights into human diseases for which a good animal model did not exist previously. These new animal models should provide the preclinical data for treatments that are developed for diseases such as Alzheimer's disease, cystic fibrosis, retinitis pigmentosa, spinal muscular atrophy, diabetes, and organ failure. These new models will help to uncover aspects and treatments of these diseases that were otherwise unattainable. The focus of this review is to describe genetically engineered pigs that have resulted in models of human diseases. PMID:25387017

  18. Moral Fantasy in Genetic Engineering.

    ERIC Educational Resources Information Center

    Boone, C. Keith

    1984-01-01

    Discusses the main ethical issues generated by the new genetics and suggests ways to think about them. Concerns include "playing God," violation of the natural order of the universe, and abuse of genetic technology. Critical distinctions for making difficult decisions about genetic engineering issues are noted. (DH)

  19. Animal Genetic Resource Trade Flows: Economic Assessment

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Throughout human history, livestock producers have relied on a vibrant international exchange of genetic resources to achieve improvements in the quality and productivity of their animals. In recent years, however, some observers have argued that changes in the legal, technological, and economic env...

  20. The Genetic Architecture of Domestication in Animals

    PubMed Central

    Wright, Dominic

    2015-01-01

    Domestication has been essential to the progress of human civilization, and the process itself has fascinated biologists for hundreds of years. Domestication has led to a series of remarkable changes in a variety of plants and animals, in what is termed the “domestication phenotype.” In domesticated animals, this general phenotype typically consists of similar changes in tameness, behavior, size/morphology, color, brain composition, and adrenal gland size. This domestication phenotype is seen in a range of different animals. However, the genetic basis of these associated changes is still puzzling. The genes for these different traits tend to be grouped together in clusters in the genome, though it is still not clear whether these clusters represent pleiotropic effects, or are in fact linked clusters. This review focuses on what is currently known about the genetic architecture of domesticated animal species, if genes of large effect (often referred to as major genes) are prevalent in driving the domestication phenotype, and whether pleiotropy can explain the loci underpinning these diverse traits being colocated. PMID:26512200

  1. Photothermal Genetic Engineering

    E-print Network

    Deisseroth, Karl

    Optical methods for manipulation of cellular function have enabled deconstruction of genetic and neural circuits in vitro and in vivo. Plasmonic gold nanomaterials provide an alternative platform for external optical ...

  2. Genetic engineering of Geobacillus spp.

    PubMed

    Kananavi?i?t?, R?ta; ?itavi?ius, Donaldas

    2015-04-01

    Members of the genus Geobacillus are thermophiles that are of great biotechnological importance, since they are sources of many thermostable enzymes. Because of their metabolic versatility, geobacilli can be used as whole-cell catalysts in processes such as bioconversion and bioremediation. The effective employment of Geobacillus spp. requires the development of reliable methods for genetic engineering of these bacteria. Currently, genetic manipulation tools and protocols are under rapid development. However, there are several convenient cloning vectors, some of which replicate autonomously, while others are suitable for the genetic modification of chromosomal genes. Gene expression systems are also intensively studied. Combining these tools together with proper techniques for DNA transfer, some Geobacillus strains were shown to be valuable producers of recombinant proteins and industrially important biochemicals, such as ethanol or isobutanol. This review encompasses the progress made in the genetic engineering of Geobacillus spp. and surveys the vectors and transformation methods that are available for this genus. PMID:25659824

  3. Genetic Engineering Workshop Report, 2010

    SciTech Connect

    Allen, J; Slezak, T

    2010-11-03

    The Lawrence Livermore National Laboratory (LLNL) Bioinformatics group has recently taken on a role in DTRA's Transformation Medical Technologies (TMT) program. The high-level goal of TMT is to accelerate the development of broad-spectrum countermeasures. To achieve this goal, there is a need to assess the genetic engineering (GE) approaches, potential application as well as detection and mitigation strategies. LLNL was tasked to coordinate a workshop to determine the scope of investments that DTRA should make to stay current with the rapid advances in genetic engineering technologies, so that accidental or malicious uses of GE technologies could be adequately detected and characterized. Attachment A is an earlier report produced by LLNL for TMT that provides some relevant background on Genetic Engineering detection. A workshop was held on September 23-24, 2010 in Springfield, Virginia. It was attended by a total of 55 people (see Attachment B). Twenty four (44%) of the attendees were academic researchers involved in GE or bioinformatics technology, 6 (11%) were from DTRA or the TMT program management, 7 (13%) were current TMT performers (including Jonathan Allen and Tom Slezak of LLNL who hosted the workshop), 11 (20%) were from other Federal agencies, and 7 (13%) were from industries that are involved in genetic engineering. Several attendees could be placed in multiple categories. There were 26 attendees (47%) who were from out of the DC area and received travel assistance through Invitational Travel Orders (ITOs). We note that this workshop could not have been as successful without the ability to invite experts from outside of the Beltway region. This workshop was an unclassified discussion of the science behind current genetic engineering capabilities. US citizenship was not required for attendance. While this may have limited some discussions concerning risk, we felt that it was more important for this first workshop to focus on the scientific state of the art. We also consciously chose to not dwell on matters of policy (for example, screening of commercial gene or oligo synthesis orders), as multiple other forums for policy discussion have taken place in recent years. We acknowledge that other workshops on topics relevant to genetic engineering should be held, some of which may need to take place at higher classification levels. The workshop moderators would like to acknowledge the enthusiastic participation of the attendees in the discussions. Special thanks are given to Sofi Ibrahim, for his extensive assistance on helping this report reach its final form. The genetic engineering workshop brought together a diverse mix of genetic engineering pioneers and experts, Federal agency representatives concerned with abuses of genetic engineering, TMT performers, bioinformatics experts, and representatives from industry involved with large-scale genetic engineering and synthetic biology. Several talks established the current range of genetic engineering capabilities and the relative difficulties of identifying and characterizing the results of their use. Extensive discussions established a number of recommendations to DTRA of how to direct future research investments so that any mis-use of genetic engineering techniques can be promptly identified and characterized.

  4. Naturalness and the genetic modification of animals.

    PubMed

    Verhoog, Henk

    2003-07-01

    In the past few years it has been recognised that so-called intrinsic concerns about genetic modification (GM) of plants and animals, for food in particular, have an important role in the public perception of GM. One of these concerns is the view that GM is 'unnatural'. This article gives an overview of the often conflicting views on the argument of unnaturalness in books and reports. The author gives a new direction to this discussion, by contrasting the common sense view of nature and animals, with the scientific concept of nature and what is natural. The view of nature and what is natural is always normative. This is illustrated by making explicit the concept of nature in organic farming, which explains why GM is rejected. PMID:12837612

  5. The Genetics of Deafness in Domestic Animals

    PubMed Central

    Strain, George M.

    2015-01-01

    Although deafness can be acquired throughout an animal’s life from a variety of causes, hereditary deafness, especially congenital hereditary deafness, is a significant problem in several species. Extensive reviews exist of the genetics of deafness in humans and mice, but not for deafness in domestic animals. Hereditary deafness in many species and breeds is associated with loci for white pigmentation, where the cochlear pathology is cochleo-saccular. In other cases, there is no pigmentation association and the cochlear pathology is neuroepithelial. Late onset hereditary deafness has recently been identified in dogs and may be present but not yet recognized in other species. Few genes responsible for deafness have been identified in animals, but progress has been made for identifying genes responsible for the associated pigmentation phenotypes. Across species, the genes identified with deafness or white pigmentation patterns include MITF, PMEL, KIT, EDNRB, CDH23, TYR, and TRPM1 in dog, cat, horse, cow, pig, sheep, ferret, mink, camelid, and rabbit. Multiple causative genes are present in some species. Significant work remains in many cases to identify specific chromosomal deafness genes so that DNA testing can be used to identify carriers of the mutated genes and thereby reduce deafness prevalence. PMID:26664958

  6. Applications of genetic engineering in veterinary medicine.

    PubMed

    Ciftci, K; Trovitch, P

    2000-09-15

    A mutation of just one gene will cause abnormal cell behavior leading to the synthesis of a dysfunctional protein. This mutation will inevitably result in the cell functioning only marginally or not at all. Other genetic mutations interfere with the cell's normal life cycle, especially the cell-division cycle. The goal behind recombinant DNA technology is to deliver the correct version of a mutated gene to the cell so that the expression will lead to the normal production of protein and the restoration of normal cell function. This can be considered qualitatively different from other conventional treatments due to genetic material being a putative therapeutic agent. By altering the genetic material of cells, gene therapy may correct, or one day cure, the specific disease pathophysiology. Genetic engineering has been used in veterinary medicine to diagnose, prevent and treat diseases, breed different species and produce transgenic animals for therapeutic proteins or xenografting. In this review the current status of recombinant DNA technology and its application in veterinary medicine together with the obstacles to, and applications of, genetic engineering in veterinary medicine are discussed. PMID:10967221

  7. "Genetically Engineered" Nanoelectronics

    NASA Technical Reports Server (NTRS)

    Klimeck, Gerhard; Salazar-Lazaro, Carlos H.; Stoica, Adrian; Cwik, Thomas

    2000-01-01

    The quantum mechanical functionality of nanoelectronic devices such as resonant tunneling diodes (RTDs), quantum well infrared-photodetectors (QWIPs), quantum well lasers, and heterostructure field effect transistors (HFETs) is enabled by material variations on an atomic scale. The design and optimization of such devices requires a fundamental understanding of electron transport in such dimensions. The Nanoelectronic Modeling Tool (NEMO) is a general-purpose quantum device design and analysis tool based on a fundamental non-equilibrium electron transport theory. NEW was combined with a parallelized genetic algorithm package (PGAPACK) to evolve structural and material parameters to match a desired set of experimental data. A numerical experiment that evolves structural variations such as layer widths and doping concentrations is performed to analyze an experimental current voltage characteristic. The genetic algorithm is found to drive the NEMO simulation parameters close to the experimentally prescribed layer thicknesses and doping profiles. With such a quantitative agreement between theory and experiment design synthesis can be performed.

  8. GENETIC ENGINEERING PRODUCER FACT SHEET 2 Methods to Maintain Genetic

    E-print Network

    Bradford, Kent

    GENETIC ENGINEERING PRODUCER FACT SHEET 2 Methods to Maintain Genetic Purity of Seed Stocks KENT J yield. Seeds carry the genetic traits incorporated by years of breeding and selection to create quality. The genetic purity of seeds (i.e., the percentage of contamination by seeds or genetic material

  9. Genetic Engineering and Crop Production.

    ERIC Educational Resources Information Center

    Jones, Helen C.; Frost, S.

    1991-01-01

    With a spotlight upon current agricultural difficulties and environmental dilemmas, this paper considers both the extant and potential applications of genetic engineering with respect to crop production. The nonagricultural factors most likely to sway the impact of this emergent technology upon future crop production are illustrated. (JJK)

  10. MILESTONES LEADING TO THE GENETIC ENGINEERING OF BACULOVIRUSES AS EXPRESSION

    E-print Network

    Summers, Max D.

    MILESTONES LEADING TO THE GENETIC ENGINEERING OF BACULOVIRUSES AS EXPRESSION VECTOR SYSTEMS and Infection VI. Genetically Engineered Viral Pesticides A. Development of Genetically Engineered Baculovirus, therapeutics, and diagnostics. The genetic engineering of the baculovirus polyhedrin gene promoter

  11. Genetically Engineered Mouse Models of Pituitary Tumors

    PubMed Central

    Cano, David A.; Soto-Moreno, Alfonso; Leal-Cerro, Alfonso

    2014-01-01

    Animal models constitute valuable tools for investigating the pathogenesis of cancer as well as for preclinical testing of novel therapeutics approaches. However, the pathogenic mechanisms of pituitary-tumor formation remain poorly understood, particularly in sporadic adenomas, thus, making it a challenge to model pituitary tumors in mice. Nevertheless, genetically engineered mouse models (GEMMs) of pituitary tumors have provided important insight into pituitary tumor biology. In this paper, we review various GEMMs of pituitary tumors, highlighting their contributions and limitations, and discuss opportunities for research in the field. PMID:25136513

  12. Genetic Programming Evolution of Controllers for 3D Character Animation

    E-print Network

    Fernandez, Thomas

    Genetic Programming Evolution of Controllers for 3­D Character Animation Larry Gritz James K. Hahn Pixar Animation Studios 1001 W. Cutting Blvd. Richmond, CA 94804 lg@pixar.com The George Washington character animation requires an animator to specify the values for all degrees of freedom of an articulated

  13. Genetically Engineered Microelectronic Infrared Filters

    NASA Technical Reports Server (NTRS)

    Cwik, Tom; Klimeck, Gerhard

    1998-01-01

    A genetic algorithm is used for design of infrared filters and in the understanding of the material structure of a resonant tunneling diode. These two components are examples of microdevices and nanodevices that can be numerically simulated using fundamental mathematical and physical models. Because the number of parameters that can be used in the design of one of these devices is large, and because experimental exploration of the design space is unfeasible, reliable software models integrated with global optimization methods are examined The genetic algorithm and engineering design codes have been implemented on massively parallel computers to exploit their high performance. Design results are presented for the infrared filter showing new and optimized device design. Results for nanodevices are presented in a companion paper at this workshop.

  14. [Ethical challenges of genetic manipulation and research with animals].

    PubMed

    Rodríguez Yunta, Eduardo

    2012-01-01

    Research with animals presents ethical questions both for being used as models of human diseases and for being a prerequisite for trials in humans, as in the introduction of genetic modifications. Some of these questions refer to the fact that, as models, they do not fully represent the human condition; that conducting toxicity tests causes great harm to animals; that their nature is altered by genetic modifications and that introducing genetically modified organisms is a risk. The use of animals in research for the benefit of humans imposes the moral responsibility to respect them, not making them suffer unnecessarily, since they are living beings capable of feeling. PMID:23338641

  15. Genetically Engineered Immunotherapy for Advanced Cancer

    Cancer.gov

    In this trial, doctors will collect T lymphocytes from patients with advanced mesothelin-expressing cancer and genetically engineer them to recognize mesothelin. The gene-engineered cells will be multiplied and infused into the patient to fight the cancer

  16. Engineering Microbiomes to Improve Plant and Animal Health.

    PubMed

    Mueller, U G; Sachs, J L

    2015-10-01

    Animal and plant microbiomes encompass diverse microbial communities that colonize every accessible host tissue. These microbiomes enhance host functions, contributing to host health and fitness. A novel approach to improve animal and plant fitness is to artificially select upon microbiomes, thus engineering evolved microbiomes with specific effects on host fitness. We call this engineering approach host-mediated microbiome selection, because this method selects upon microbial communities indirectly through the host and leverages host traits that evolved to influence microbiomes. In essence, host phenotypes are used as probes to gauge and manipulate those microbiome functions that impact host fitness. To facilitate research on host-mediated microbiome engineering, we explain and compare the principal methods to impose artificial selection on microbiomes; discuss advantages and potential challenges of each method; offer a skeptical appraisal of each method in light of these potential challenges; and outline experimental strategies to optimize microbiome engineering. Finally, we develop a predictive framework for microbiome engineering that organizes research around principles of artificial selection, quantitative genetics, and microbial community-ecology. PMID:26422463

  17. Enhanced Genetic Tools for Engineering Multigene Traits into Green Algae

    PubMed Central

    Rasala, Beth A.; Chao, Syh-Shiuan; Pier, Matthew; Barrera, Daniel J.; Mayfield, Stephen P.

    2014-01-01

    Transgenic microalgae have the potential to impact many diverse biotechnological industries including energy, human and animal nutrition, pharmaceuticals, health and beauty, and specialty chemicals. However, major obstacles to sophisticated genetic and metabolic engineering in algae have been the lack of well-characterized transformation vectors to direct engineered gene products to specific subcellular locations, and the inability to robustly express multiple nuclear-encoded transgenes within a single cell. Here we validate a set of genetic tools that enable protein targeting to distinct subcellular locations, and present two complementary methods for multigene engineering in the eukaryotic green microalga Chlamydomonas reinhardtii. The tools described here will enable advanced metabolic and genetic engineering to promote microalgae biotechnology and product commercialization. PMID:24710110

  18. Reproductive biotechnologies and management of animal genetic resources

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Global awareness has increased efforts to conserve animal genetic resources (AnGR). Ex-situ conservation and management of AnGR is exclusively dependent upon an array of reproductive and genetic biotechnologies. These technologies range from well established protocols, e.g., cryopreservation of sper...

  19. SEARCH ENGINE TUNING WITH GENETIC ALGORITHMS Jeffrey Kyle Elser

    E-print Network

    Dyer, Bill

    SEARCH ENGINE TUNING WITH GENETIC ALGORITHMS by Jeffrey Kyle Elser A project submitted in partial ........................................................................................................9 Genetic Algorithms Background....................................................................................................................14 Genetic Algorithm Configuration

  20. Review: domestic animal forensic genetics - biological evidence, genetic markers, analytical approaches and challenges.

    PubMed

    Kanthaswamy, S

    2015-10-01

    This review highlights the importance of domestic animal genetic evidence sources, genetic testing, markers and analytical approaches as well as the challenges this field is facing in view of the de facto 'gold standard' human DNA identification. Because of the genetic similarity between humans and domestic animals, genetic analysis of domestic animal hair, saliva, urine, blood and other biological material has generated vital investigative leads that have been admitted into a variety of court proceedings, including criminal and civil litigation. Information on validated short tandem repeat, single nucleotide polymorphism and mitochondrial DNA markers and public access to genetic databases for forensic DNA analysis is becoming readily available. Although the fundamental aspects of animal forensic genetic testing may be reliable and acceptable, animal forensic testing still lacks the standardized testing protocols that human genetic profiling requires, probably because of the absence of monetary support from government agencies and the difficulty in promoting cooperation among competing laboratories. Moreover, there is a lack in consensus about how to best present the results and expert opinion to comply with court standards and bear judicial scrutiny. This has been the single most persistent challenge ever since the earliest use of domestic animal forensic genetic testing in a criminal case in the mid-1990s. Crime laboratory accreditation ensures that genetic test results have the courts' confidence. Because accreditation requires significant commitments of effort, time and resources, the vast majority of animal forensic genetic laboratories are not accredited nor are their analysts certified forensic examiners. The relevance of domestic animal forensic genetics in the criminal justice system is undeniable. However, further improvements are needed in a wide range of supporting resources, including standardized quality assurance and control protocols for sample handling, evidence testing, statistical analysis and reporting that meet the rules of scientific acceptance, reliability and human forensic identification standards. PMID:26364867

  1. Positive Bioluminescence Imaging of MicroRNA Expression in Small Animal Models Using an Engineered Genetic-Switch Expression System, RILES.

    PubMed

    Baril, Patrick; Pichon, Chantal

    2016-01-01

    MicroRNAs (miRNAs) are a class of small, noncoding RNAs which regulate gene expression by directing their target mRNA for degradation or translational repression. Since their discovery in the early 1990s, miRNAs have emerged as key components in the posttranscriptional regulation of gene networks, shaping many biological processes from development, morphogenesis, differentiation, proliferation and apoptosis. Although understanding of the molecular basis of miRNA biology is improving, methods to monitor the dynamic and the spatiotemporal aspects of miRNA expression under physiopathological conditions are required. However, monitoring of miRNAs is difficult due to their small size, low abundance, high degree of sequence similarity, and their dynamic expression pattern which is subjected to tight transcriptional and post-transcriptional controls. Recently, we developed a miRNA monitoring system called RILES, standing for RNAi-inducible expression system, which relies on an engineered regulatable expression system, to switch on the expression of the luciferase gene when the targeted miRNA is expressed in cells. We demonstrated that RILES is a specific, sensitive, and robust method to determine the fine-tuning of miRNA expression during the development of an experimental pathological process in mice. Because RILES offers the possibility for longitudinal studies on individual subjects, sharper insights into miRNA regulation can be generated, with applications in physiology, pathophysiology and development of RNAi-based therapies. This chapter describes methods and protocols to monitor the expression of myomiR-206, -1, and -133 in the tibialis anterior muscle of mice. These protocols can be used and adapted to monitor the expression of other miRNAs in other biological processes. PMID:26530925

  2. Genetic Engineering: The Modification of Man

    ERIC Educational Resources Information Center

    Sinsheimer, Robert L.

    1970-01-01

    Describes somatic and genetic manipulations of individual genotypes, using diabetes control as an example of the first mode that is potentially realizable be derepression or viral transduction of genes. Advocates the use of genetic engineering of the second mode to remove man from his biological limitations, but offers maxims to ensure the…

  3. Pertussis toxins, other antigens become likely targets for genetic engineering

    SciTech Connect

    Marwick, C.

    1990-11-14

    Genetically engineered pertussis vaccines have yet to be fully tested clinically. But early human, animal, and in vitro studies indicate effectiveness in reducing toxic effects due to Bordetella pertussis. The licensed pertussis vaccines consists of inactivated whole cells of the organism. Although highly effective, they have been associated with neurologic complications. While the evidence continues to mount that these complications are extremely rare, if they occur at all, it has affected the public's acceptance of pertussis immunization.

  4. Genetic engineering and the use of bovine somatotropin

    SciTech Connect

    Grossman, C.J. Xavier Univ., Cincinnati, OH )

    1990-08-22

    During the last decade there has been an unfortunate reappearance in our society of an antitechnology and antiscience attitude. This is exemplified by those advocates who would ban all animals in research and block fetal tissue studies and by those who support creationism. An especially vocal group consists of those people who are against any form of genetic engineering regardless of the benefits or potential benefits that might be realized.

  5. POLICIES FOR THE MANAGEMENT OF ANIMAL GENETIC RESOURCES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The antagonism between national livestock sector economic growth and development and the in-situ/in-vivo conservation of animal genetic resources (AnGR) create a need for a policy framework that will promote both economic growth and AnGR conservation for future generations. It is suggested that poli...

  6. HYPERSPECTRAL IMAGING PHENOMENOLOGY OF GENETICALLY ENGINEERED PLANT SENTINELS

    E-print Network

    Kerekes, John

    HYPERSPECTRAL IMAGING PHENOMENOLOGY OF GENETICALLY ENGINEERED PLANT SENTINELS D. Simmonsa , J genetically engineered plants that display a visible reaction to chemical inducers in their environment Institute of Technology b Gitam Technologies, Inc., c Electrical Engineering Department, Wright State

  7. Genetic Animal Models of Parkinson’s Disease

    PubMed Central

    Dawson, Ted M.; Ko, Han Seok; Dawson, Valina L.

    2010-01-01

    Parkinson’s disease (PD) is a progressive neurodegenerative disorder that is characterized by the degeneration of dopamine (DA) and non-DA neurons, the almost uniform presence of Lewy bodies, and motor deficits. Although the majority of PD is sporadic, specific genetic defects in rare familial cases have provided unique insights into the pathogenesis of PD. Through the creation of animal and cellular models of mutations in LRRK2 and ?-synuclein, which are linked to autosomal dominant PD, and mutations in parkin, DJ-1, and PINK1, which are responsible for autosomal recessive PD, insight into the molecular mechanisms of this disorder are leading to new ideas about the pathogenesis of PD. In this review, we discuss the animal models for these genetic causes of PD, their limitations and value. Moreover, we discuss future directions and potential strategies for optimization of the genetic models. PMID:20547124

  8. Engineering Values Into Genetic Engineering: A Proposed Analytic Framework for Scientific Social Responsibility.

    PubMed

    Sankar, Pamela L; Cho, Mildred K

    2015-12-01

    Recent experiments have been used to "edit" genomes of various plant, animal and other species, including humans, with unprecedented precision. Furthermore, editing the Cas9 endonuclease gene with a gene encoding the desired guide RNA into an organism, adjacent to an altered gene, could create a "gene drive" that could spread a trait through an entire population of organisms. These experiments represent advances along a spectrum of technological abilities that genetic engineers have been working on since the advent of recombinant DNA techniques. The scientific and bioethics communities have built substantial literatures about the ethical and policy implications of genetic engineering, especially in the age of bioterrorism. However, recent CRISPr/Cas experiments have triggered a rehashing of previous policy discussions, suggesting that the scientific community requires guidance on how to think about social responsibility. We propose a framework to enable analysis of social responsibility, using two examples of genetic engineering experiments. PMID:26632356

  9. Genetically engineered nanocarriers for drug delivery

    PubMed Central

    Shi, Pu; Gustafson, Joshua A; MacKay, J Andrew

    2014-01-01

    Cytotoxicity, low water solubility, rapid clearance from circulation, and off-target side-effects are common drawbacks of conventional small-molecule drugs. To overcome these shortcomings, many multifunctional nanocarriers have been proposed to enhance drug delivery. In concept, multifunctional nanoparticles might carry multiple agents, control release rate, biodegrade, and utilize target-mediated drug delivery; however, the design of these particles presents many challenges at the stage of pharmaceutical development. An emerging solution to improve control over these particles is to turn to genetic engineering. Genetically engineered nanocarriers are precisely controlled in size and structure and can provide specific control over sites for chemical attachment of drugs. Genetically engineered drug carriers that assemble nanostructures including nanoparticles and nanofibers can be polymeric or non-polymeric. This review summarizes the recent development of applications in drug and gene delivery utilizing nanostructures of polymeric genetically engineered drug carriers such as elastin-like polypeptides, silk-like polypeptides, and silk-elastin-like protein polymers, and non-polymeric genetically engineered drug carriers such as vault proteins and viral proteins. PMID:24741309

  10. Genetic Engineering Strategies for Enhanced Biodiesel Production.

    PubMed

    Hegde, Krishnamoorthy; Chandra, Niharika; Sarma, Saurabh Jyoti; Brar, Satinder Kaur; Veeranki, Venkata Dasu

    2015-07-01

    The focus on biodiesel research has shown a tremendous growth over the last few years. Several microbial and plant sources are being explored for the sustainable biodiesel production to replace the petroleum diesel. Conventional methods of biodiesel production have several limitations related to yield and quality, which led to development of new engineering strategies to improve the biodiesel production in plants, and microorganisms. Substantial progress in utilizing algae, yeast, and Escherichia coli for the renewable production of biodiesel feedstock via genetic engineering of fatty acid metabolic pathways has been reported in the past few years. However, in most of the cases, the successful commercialization of such engineering strategies for sustainable biodiesel production is yet to be seen. This paper systematically presents the drawbacks in the conventional methods for biodiesel production and an exhaustive review on the present status of research in genetic engineering strategies for production of biodiesel in plants, and microorganisms. Further, we summarize the technical challenges need to be tackled to make genetic engineering technology economically sustainable. Finally, the need and prospects of genetic engineering technology for the sustainable biodiesel production and the recommendations for the future research are discussed. PMID:25902752

  11. Genetic Engineering: and the Law

    ERIC Educational Resources Information Center

    Australian Journal of Mental Retardation, 1977

    1977-01-01

    In a transcript from a radio show, Nobel Prize Winner Sir Macfarlane Burnet stresses the critical need for scientists to regulate their own activities in genetic research and cites the potential danger of creating a new form of polio which might escape. (CL)

  12. Recent developments in the genetic engineering of barley

    SciTech Connect

    Mannonen, L.; Kauppinen, V.; Enari, T.M. )

    1994-01-01

    Cereals are the most important group of plants for human nutrition and animal feed. Partially due to the commercial value of crop plants, there has been an ever-increasing interest in using modern biotechnological methods for the improvement of the characteristics of cereals during the past decade. The rapid progress in molecular biology, plant cell culture techniques, and gene transfer technology has resulted in successful transformations of all the major cereals--maize, rice, wheat, and barley. This brings the biotechnological methods closer to the routine also in barley breeding. In this article, the current status of barley genetic engineering, including the patent situation, is reviewed. The needs aims, and possible applications of genetic engineering in barley breeding are discussed. 179 refs.

  13. Molecular scissors and their application in genetically modified farm animals.

    PubMed

    Petersen, Bjoern; Niemann, Heiner

    2015-06-01

    Molecular scissors (MS), incl. Zinc Finger Nucleases (ZFN), Transcription-activator like endoncleases (TALENS) and meganucleases possess long recognition sites and are thus capable of cutting DNA in a very specific manner. These molecular scissors mediate targeted genetic alterations by enhancing the DNA mutation rate via induction of double-strand breaks at a predetermined genomic site. Compared to conventional homologous recombination based gene targeting, MS can increase the targeting rate 10,000-fold, and gene disruption via mutagenic DNA repair is stimulated at a similar frequency. The successful application of different MS has been shown in different organisms, including insects, amphibians, plants, nematodes, and mammals, including humans. Recently, another novel class of molecular scissors was described that uses RNAs to target a specific genomic site. The CRISPR/Cas9 system is capable of targeting even multiple genomic sites in one shot and thus could be superior to ZFNs or TALEN, especially by its easy design. MS can be successfully employed for improving the understanding of complex physiological systems, producing transgenic animals, incl. creating large animal models for human diseases, creating specific cell lines, and plants, and even for treating human genetic diseases. This review provides an update on molecular scissors, their underlying mechanism and focuses on new opportunities for generating genetically modified farm animals. PMID:25603988

  14. What Ideas Do Students Associate with "Biotechnology" and "Genetic Engineering"?

    ERIC Educational Resources Information Center

    Hill, Ruaraidh; Stanisstreet, Martin; Boyes, Edward

    2000-01-01

    Explores the ideas that students aged 16-19 associate with the terms 'biotechnology' and 'genetic engineering'. Indicates that some students see biotechnology as risky whereas genetic engineering was described as ethically wrong. (Author/ASK)

  15. Engineering large animal models of human disease.

    PubMed

    Whitelaw, C Bruce A; Sheets, Timothy P; Lillico, Simon G; Telugu, Bhanu P

    2016-01-01

    The recent development of gene editing tools and methodology for use in livestock enables the production of new animal disease models. These tools facilitate site-specific mutation of the genome, allowing animals carrying known human disease mutations to be produced. In this review, we describe the various gene editing tools and how they can be used for a range of large animal models of diseases. This genomic technology is in its infancy but the expectation is that through the use of gene editing tools we will see a dramatic increase in animal model resources available for both the study of human disease and the translation of this knowledge into the clinic. Comparative pathology will be central to the productive use of these animal models and the successful translation of new therapeutic strategies. © 2015 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland. PMID:26414877

  16. Genetic elements of plant viruses as tools for genetic engineering.

    PubMed Central

    Mushegian, A R; Shepherd, R J

    1995-01-01

    Viruses have developed successful strategies for propagation at the expense of their host cells. Efficient gene expression, genome multiplication, and invasion of the host are enabled by virus-encoded genetic elements, many of which are well characterized. Sequences derived from plant DNA and RNA viruses can be used to control expression of other genes in vivo. The main groups of plant virus genetic elements useful in genetic engineering are reviewed, including the signals for DNA-dependent and RNA-dependent RNA synthesis, sequences on the virus mRNAs that enable translational control, and sequences that control processing and intracellular sorting of virus proteins. Use of plant viruses as extrachromosomal expression vectors is also discussed, along with the issue of their stability. PMID:8531885

  17. Human genetic engineering demands more than a moratorium

    E-print Network

    Saha, Krishanu

    Human genetic engineering demands more than a moratorium Expert calls for a moratorium on germline; and ethical and social aspects of human genetic engineering. Decades later, these are precisely the issues we concerns by prohibiting the release of genetically engineered organisms into the environment. A few years

  18. Specific genetic modifications of domestic animals by gene targeting and animal cloning.

    PubMed

    Wang, Bin; Zhou, Jiangfeng

    2003-11-13

    The technology of gene targeting through homologous recombination has been extremely useful for elucidating gene functions in mice. The application of this technology was thought impossible in the large livestock species until the successful creation of the first mammalian clone "Dolly" the sheep. The combination of the technologies for gene targeting of somatic cells with those of animal cloning made it possible to introduce specific genetic mutations into domestic animals. In this review, the principles of gene targeting in somatic cells and the challenges of nuclear transfer using gene-targeted cells are discussed. The relevance of gene targeting in domestic animals for applications in bio-medicine and agriculture are also examined. PMID:14614774

  19. Genetic recombination between human and animal parasites creates novel strains of human pathogen.

    PubMed

    Gibson, Wendy; Peacock, Lori; Ferris, Vanessa; Fischer, Katrin; Livingstone, Jennifer; Thomas, James; Bailey, Mick

    2015-03-01

    Genetic recombination between pathogens derived from humans and livestock has the potential to create novel pathogen strains, highlighted by the influenza pandemic H1N1/09, which was derived from a re-assortment of swine, avian and human influenza A viruses. Here we investigated whether genetic recombination between subspecies of the protozoan parasite, Trypanosoma brucei, from humans and animals can generate new strains of human pathogen, T. b. rhodesiense (Tbr) responsible for sleeping sickness (Human African Trypanosomiasis, HAT) in East Africa. The trait of human infectivity in Tbr is conferred by a single gene, SRA, which is potentially transferable to the animal pathogen Tbb by sexual reproduction. We tracked the inheritance of SRA in crosses of Tbr and Tbb set up by co-transmitting genetically-engineered fluorescent parental trypanosome lines through tsetse flies. SRA was readily transferred into new genetic backgrounds by sexual reproduction between Tbr and Tbb, thus creating new strains of the human pathogen, Tbr. There was no evidence of diminished growth or transmissibility of hybrid trypanosomes carrying SRA. Although expression of SRA is critical to survival of Tbr in the human host, we show that the gene exists as a single copy in a representative collection of Tbr strains. SRA was found on one homologue of chromosome IV in the majority of Tbr isolates examined, but some Ugandan Tbr had SRA on both homologues. The mobility of SRA by genetic recombination readily explains the observed genetic variability of Tbr in East Africa. We conclude that new strains of the human pathogen Tbr are being generated continuously by recombination with the much larger pool of animal-infective trypanosomes. Such novel recombinants present a risk for future outbreaks of HAT. PMID:25816228

  20. Genetic and ecological studies of animals in Chernobyl and Fukushima.

    PubMed

    Mousseau, Timothy A; Møller, Anders P

    2014-01-01

    Recent advances in genetic and ecological studies of wild animal populations in Chernobyl and Fukushima have demonstrated significant genetic, physiological, developmental, and fitness effects stemming from exposure to radioactive contaminants. The few genetic studies that have been conducted in Chernobyl generally show elevated rates of genetic damage and mutation rates. All major taxonomic groups investigated (i.e., birds, bees, butterflies, grasshoppers, dragonflies, spiders, mammals) displayed reduced population sizes in highly radioactive parts of the Chernobyl Exclusion Zone. In Fukushima, population censuses of birds, butterflies, and cicadas suggested that abundances were negatively impacted by exposure to radioactive contaminants, while other groups (e.g., dragonflies, grasshoppers, bees, spiders) showed no significant declines, at least during the first summer following the disaster. Insufficient information exists for groups other than insects and birds to assess effects on life history at this time. The differences observed between Fukushima and Chernobyl may reflect the different times of exposure and the significance of multigenerational mutation accumulation in Chernobyl compared to Fukushima. There was considerable variation among taxa in their apparent sensitivity to radiation and this reflects in part life history, physiology, behavior, and evolutionary history. Interestingly, for birds, population declines in Chernobyl can be predicted by historical mitochondrial DNA base-pair substitution rates that may reflect intrinsic DNA repair ability. PMID:25124815

  1. Estimating genetic parameters in natural populations using the "animal model".

    PubMed Central

    Kruuk, Loeske E B

    2004-01-01

    Estimating the genetic basis of quantitative traits can be tricky for wild populations in natural environments, as environmental variation frequently obscures the underlying evolutionary patterns. I review the recent application of restricted maximum-likelihood "animal models" to multigenerational data from natural populations, and show how the estimation of variance components and prediction of breeding values using these methods offer a powerful means of tackling the potentially confounding effects of environmental variation, as well as generating a wealth of new areas of investigation. PMID:15306404

  2. Genetic algorithms applied to optics and engineering

    NASA Astrophysics Data System (ADS)

    Cuevas, Francisco; Gonzalez, Otoniel; Susuki, Yamily; Hernandez, Daniel; Rocha, Martha; Alcala, Noé

    2006-02-01

    In the last years, Soft computing techniques, such as Genetic Algorithms, Neural Networks and Fuzzy systems, have been applied in different science areas. In this work, two applications of Genetic Algorithms in engineering and optics are presented. The Genetic Algorithms are optimization, search and learning machine techniques, which work in a random way. To achieve the problem solution by using of Genetic Algorithms, an iterative process should be developed. First, the problem to solve is modelled in a mathematical way by establishing of a fitness or objective function. After, a random initial population of strings (chromosomes) codifying problem solutions is generated, which samples the search solution space of the fitness function. Then, offspring populations are generated from previous one by using genetic operators: selection, crossover and mutation. In the selection process, possible solutions are chosen depending on their fitness function value. Then, in the crossover procedure, string segments of pairs of solutions are exchanged to generate the next population. Finally, some parameters in the offspring population are changed by mutation with a low probability. Results of the application of Genetic Algorithms to solve fringe analysis and nesting in finite materials problems are presented.

  3. An animal model of differential genetic risk for methamphetamine intake

    PubMed Central

    Phillips, Tamara J.; Shabani, Shkelzen

    2015-01-01

    The question of whether genetic factors contribute to risk for methamphetamine (MA) use and dependence has not been intensively investigated. Compared to human populations, genetic animal models offer the advantages of control over genetic family history and drug exposure. Using selective breeding, we created lines of mice that differ in genetic risk for voluntary MA intake and identified the chromosomal addresses of contributory genes. A quantitative trait locus was identified on chromosome 10 that accounts for more than 50% of the genetic variance in MA intake in the selected mouse lines. In addition, behavioral and physiological screening identified differences corresponding with risk for MA intake that have generated hypotheses that are testable in humans. Heightened sensitivity to aversive and certain physiological effects of MA, such as MA-induced reduction in body temperature, are hallmarks of mice bred for low MA intake. Furthermore, unlike MA-avoiding mice, MA-preferring mice are sensitive to rewarding and reinforcing MA effects, and to MA-induced increases in brain extracellular dopamine levels. Gene expression analyses implicate the importance of a network enriched in transcription factor genes, some of which regulate the mu opioid receptor gene, Oprm1, in risk for MA use. Neuroimmune factors appear to play a role in differential response to MA between the mice bred for high and low intake. In addition, chromosome 10 candidate gene studies provide strong support for a trace amine-associated receptor 1 gene, Taar1, polymorphism in risk for MA intake. MA is a trace amine-associated receptor 1 (TAAR1) agonist, and a non-functional Taar1 allele segregates with high MA consumption. Thus, reduced TAAR1 function has the potential to increase risk for MA use. Overall, existing findings support the MA drinking lines as a powerful model for identifying genetic factors involved in determining risk for harmful MA use. Future directions include the development of a binge model of MA intake, examining the effect of withdrawal from chronic MA on MA intake, and studying potential Taar1 gene × gene and gene × environment interactions. These and other studies are intended to improve our genetic model with regard to its translational value to human addiction. PMID:26441502

  4. Genetic aspects of autism spectrum disorders: insights from animal models

    PubMed Central

    Banerjee, Swati; Riordan, Maeveen; Bhat, Manzoor A.

    2014-01-01

    Autism spectrum disorders (ASDs) are a complex neurodevelopmental disorder that display a triad of core behavioral deficits including restricted interests, often accompanied by repetitive behavior, deficits in language and communication, and an inability to engage in reciprocal social interactions. ASD is among the most heritable disorders but is not a simple disorder with a singular pathology and has a rather complex etiology. It is interesting to note that perturbations in synaptic growth, development, and stability underlie a variety of neuropsychiatric disorders, including ASD, schizophrenia, epilepsy, and intellectual disability. Biological characterization of an increasing repertoire of synaptic mutants in various model organisms indicates synaptic dysfunction as causal in the pathophysiology of ASD. Our understanding of the genes and genetic pathways that contribute toward the formation, stabilization, and maintenance of functional synapses coupled with an in-depth phenotypic analysis of the cellular and behavioral characteristics is therefore essential to unraveling the pathogenesis of these disorders. In this review, we discuss the genetic aspects of ASD emphasizing on the well conserved set of genes and genetic pathways implicated in this disorder, many of which contribute to synapse assembly and maintenance across species. We also review how fundamental research using animal models is providing key insights into the various facets of human ASD. PMID:24605088

  5. Designing and engineering evolutionary robust genetic circuits

    PubMed Central

    2010-01-01

    Background One problem with engineered genetic circuits in synthetic microbes is their stability over evolutionary time in the absence of selective pressure. Since design of a selective environment for maintaining function of a circuit will be unique to every circuit, general design principles are needed for engineering evolutionary robust circuits that permit the long-term study or applied use of synthetic circuits. Results We first measured the stability of two BioBrick-assembled genetic circuits propagated in Escherichia coli over multiple generations and the mutations that caused their loss-of-function. The first circuit, T9002, loses function in less than 20 generations and the mutation that repeatedly causes its loss-of-function is a deletion between two homologous transcriptional terminators. To measure the effect between transcriptional terminator homology levels and evolutionary stability, we re-engineered six versions of T9002 with a different transcriptional terminator at the end of the circuit. When there is no homology between terminators, the evolutionary half-life of this circuit is significantly improved over 2-fold and is independent of the expression level. Removing homology between terminators and decreasing expression level 4-fold increases the evolutionary half-life over 17-fold. The second circuit, I7101, loses function in less than 50 generations due to a deletion between repeated operator sequences in the promoter. This circuit was re-engineered with different promoters from a promoter library and using a kanamycin resistance gene (kanR) within the circuit to put a selective pressure on the promoter. The evolutionary stability dynamics and loss-of-function mutations in all these circuits are described. We also found that on average, evolutionary half-life exponentially decreases with increasing expression levels. Conclusions A wide variety of loss-of-function mutations are observed in BioBrick-assembled genetic circuits including point mutations, small insertions and deletions, large deletions, and insertion sequence (IS) element insertions that often occur in the scar sequence between parts. Promoter mutations are selected for more than any other biological part. Genetic circuits can be re-engineered to be more evolutionary robust with a few simple design principles: high expression of genetic circuits comes with the cost of low evolutionary stability, avoid repeated sequences, and the use of inducible promoters increases stability. Inclusion of an antibiotic resistance gene within the circuit does not ensure evolutionary stability. PMID:21040586

  6. Genetic engineering of cyanobacteria as biodiesel feedstock.

    SciTech Connect

    Ruffing, Anne M.; Trahan, Christine Alexandra; Jones, Howland D. T.

    2013-01-01

    Algal biofuels are a renewable energy source with the potential to replace conventional petroleum-based fuels, while simultaneously reducing greenhouse gas emissions. The economic feasibility of commercial algal fuel production, however, is limited by low productivity of the natural algal strains. The project described in this SAND report addresses this low algal productivity by genetically engineering cyanobacteria (i.e. blue-green algae) to produce free fatty acids as fuel precursors. The engineered strains were characterized using Sandia's unique imaging capabilities along with cutting-edge RNA-seq technology. These tools are applied to identify additional genetic targets for improving fuel production in cyanobacteria. This proof-of-concept study demonstrates successful fuel production from engineered cyanobacteria, identifies potential limitations, and investigates several strategies to overcome these limitations. This project was funded from FY10-FY13 through the President Harry S. Truman Fellowship in National Security Science and Engineering, a program sponsored by the LDRD office at Sandia National Laboratories.

  7. Reverse engineering gene networks: Integrating genetic perturbations with dynamical modeling

    E-print Network

    Hasty, Jeff

    Reverse engineering gene networks: Integrating genetic perturbations with dynamical modeling Jesper contained in the genetic circuit. A natural plan of attack is to use a forward engineering approach, wherebyDynamics and Department of Biomedical Engineering, Boston University, Boston, MA 02215; Division of Computational Biology

  8. Human Genetic Engineering: A Survey of Student Value Stances

    ERIC Educational Resources Information Center

    Wilson, Sara McCormack; And Others

    1975-01-01

    Assesses the values of high school and college students relative to human genetic engineering and recommends that biology educators explore instructional strategies merging human genetic information with value clarification techniques. (LS)

  9. Genetic engineering of microorganisms for biodiesel production

    PubMed Central

    Lin, Hui; Wang, Qun; Shen, Qi; Zhan, Jumei; Zhao, Yuhua

    2013-01-01

    Biodiesel, as one type of renewable energy, is an ideal substitute for petroleum-based diesel fuel and is usually made from triacylglycerides by transesterification with alcohols. Biodiesel production based on microbial fermentation aiming to establish more efficient, less-cost and sustainable biodiesel production strategies is under current investigation by various start-up biotechnology companies and research centers. Genetic engineering plays a key role in the transformation of microbes into the desired cell factories with high efficiency of biodiesel production. Here, we present an overview of principal microorganisms used in the microbial biodiesel production and recent advances in metabolic engineering for the modification required. Overexpression or deletion of the related enzymes for de novo synthesis of biodiesel is highlighted with relevant examples. PMID:23222170

  10. 76 FR 5780 - Determination of Regulated Status of Alfalfa Genetically Engineered for Tolerance to the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-02

    ...This notice advises the public of the Animal and Plant Health Inspection Service's (APHIS) record of decision and determination on the petition regarding the regulated status of alfalfa genetically engineered for tolerance to the herbicide glyphosate based on APHIS' final environmental impact...

  11. Can Man Control His Biological Evolution? A Symposium on Genetic Engineering. Genetic Engineering

    ERIC Educational Resources Information Center

    Ramsey, Paul

    1972-01-01

    Presented are issues related to genetic engineering. Increased knowledge of techniques to manipulate genes are apt to create confusion about moral values in relation to unborn babies and other living organisms on earth. Human beings may use this knowledge to disturb the balance maintained by nature. (PS)

  12. Natural and Genetically Engineered Proteins for Tissue Engineering

    PubMed Central

    Gomes, Sílvia; Leonor, Isabel B.; Mano, João F.; Reis, Rui L.

    2011-01-01

    To overcome the limitations of traditionally used autografts, allografts and, to a lesser extent, synthetic materials, there is the need to develop a new generation of scaffolds with adequate mechanical and structural support, control of cell attachment, migration, proliferation and differentiation and with bio-resorbable features. This suite of properties would allow the body to heal itself at the same rate as implant degradation. Genetic engineering offers a route to this level of control of biomaterial systems. The possibility of expressing biological components in nature and to modify or bioengineer them further, offers a path towards multifunctional biomaterial systems. This includes opportunities to generate new protein sequences, new self-assembling peptides or fusions of different bioactive domains or protein motifs. New protein sequences with tunable properties can be generated that can be used as new biomaterials. In this review we address some of the most frequently used proteins for tissue engineering and biomedical applications and describe the techniques most commonly used to functionalize protein-based biomaterials by combining them with bioactive molecules to enhance biological performance. We also highlight the use of genetic engineering, for protein heterologous expression and the synthesis of new protein-based biopolymers, focusing the advantages of these functionalized biopolymers when compared with their counterparts extracted directly from nature and modified by techniques such as physical adsorption or chemical modification. PMID:22058578

  13. Seeking perfection: a Kantian look at human genetic engineering.

    PubMed

    Gunderson, Martin

    2007-01-01

    It is tempting to argue that Kantian moral philosophy justifies prohibiting both human germ-line genetic engineering and non-therapeutic genetic engineering because they fail to respect human dignity. There are, however, good reasons for resisting this temptation. In fact, Kant's moral philosophy provides reasons that support genetic engineering-even germ-line and non-therapeutic. This is true of Kant's imperfect duties to seek one's own perfection and the happiness of others. It is also true of the categorical imperative. Kant's moral philosophy does, however, provide limits to justifiable genetic engineering. PMID:17516148

  14. Use of genetically-engineered pig donors in islet transplantation

    PubMed Central

    Bottino, Rita; Trucco, Massimo

    2015-01-01

    Type 1 diabetes (T1D) is an autoimmune disease wherein the pancreas does not produce enough insulin due to islet beta cell destruction. Despite improvements in delivering exogenous insulin to T1D patients, pancreas or islet transplantation remains the best way to regulate their glycaemia. Results from experimental islet transplantation have improved dramatically in the last 15 years, to the point where it can be comparable to pancreas transplantation, but without the accompanying morbidity associated with this procedure. As with other transplants, the limiting factor in islet allotransplantation is the relatively small number of organs made available by deceased human donors throughout the world. A strong case can be made for islet xenotransplantation to fill the gap between supply and demand; however, transplantation across species presents challenges that are unique to that setting. In the search for the most suitable animal for human xenotransplantation, the pig has many advantages that make it the likely animal of choice. Potentially one of the most beneficial advantages is the ability to genetically engineer porcine donors to be more compatible with human recipients. Several genetic manipulations have already proven useful in relation to hyperacute rejection and inflammation (instant blood mediated inflammatory reaction), with the potential of even further advancement in the near future. PMID:26722651

  15. Genetic engineering with T cell receptors?

    PubMed Central

    Zhang, Ling; Morgan, Richard A.

    2011-01-01

    In the past two decades, human gene transfer research has been translated from a laboratory technology to clinical evaluation. The success of adoptive transfer of tumor-reactive lymphocytes to treat the patients with metastatic melanoma has led to new strategies to redirect normal T cells to recognize tumor antigens by genetic engineering with tumor antigen-specific T cell receptor (TCR) genes. This new strategy can generate large numbers of defined antigen-specific cells for therapeutic application. Much progress has been made to TCR gene transfer systems by optimizing gene expression and gene transfer protocols. Vector and protein modifications have enabled excellent expression of introduced TCR chains in human lymphocytes with reduced mis-pairing between the introduced and endogenous TCR chains. Initial clinical studies have demonstrated that TCR gene-engineered T cells could mediate tumor regression in vivo. In this review, we discuss the progress and prospects of TCR gene-engineered T cells as a therapeutic strategy for treating patients with melanoma and other cancers. PMID:22178904

  16. Modularization of genetic elements promotes synthetic metabolic engineering.

    PubMed

    Qi, Hao; Li, Bing-Zhi; Zhang, Wen-Qian; Liu, Duo; Yuan, Ying-Jin

    2015-11-15

    In the context of emerging synthetic biology, metabolic engineering is moving to the next stage powered by new technologies. Systematical modularization of genetic elements makes it more convenient to engineer biological systems for chemical production or other desired purposes. In the past few years, progresses were made in engineering metabolic pathway using synthetic biology tools. Here, we spotlighted the topic of implementation of modularized genetic elements in metabolic engineering. First, we overviewed the principle developed for modularizing genetic elements and then discussed how the genetic modules advanced metabolic engineering studies. Next, we picked up some milestones of engineered metabolic pathway achieved in the past few years. Last, we discussed the rapid raised synthetic biology field of "building a genome" and the potential in metabolic engineering. PMID:25868805

  17. Genetic Engineering of Plants. Agricultural Research Opportunities and Policy Concerns.

    ERIC Educational Resources Information Center

    Roberts, Leslie

    Plant scientists and science policymakers from government, private companies, and universities met at a convocation on the genetic engineering of plants. During the convocation, researchers described some of the ways genetic engineering may be used to address agricultural problems. Policymakers delineated and debated changes in research funding…

  18. Conservation of Swine Genetics by the National Animal Germplasm Program (NAGP) after One Decade

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Given the continued threats to genetic diversity, and that this is the 10th year NAGP has been operating, it is useful to assess the progress made to date in securing animal genetic resources in general and swine genetic resources specifically. In 1999 the USDA-Agricultural Research Service (ARS) es...

  19. About making a CHO production cell line “research-friendly” by genetic engineering

    E-print Network

    2011-11-22

    About making a CHO production cell line “research-friendly” by genetic engineering Bernd Voedisch1*, Agnès Patoux1, Jildou Sterkenburgh2, Mirjam Buchs1, Emily Barry3, Cyril Allard1, Sabine Geisse1 From 22nd European Society for Animal Cell Technology... -P132 Cite this article as: Voedisch et al.: About making a CHO production cell line “research-friendly” by genetic engineering. BMC Proceedings 2011 5 (Suppl 8):P132. Submit your next manuscript to BioMed Central and take full advantage of...

  20. Geomorphological implications of engineering bed sediments by lotic animals

    NASA Astrophysics Data System (ADS)

    Statzner, Bernhard

    2012-07-01

    Recent developments in zoogeomorphology in combination with the increasing interest of ecologists in ecosystem engineering by organisms initiated considerable research on the impact of running water (i.e., lotic) animals (and other organisms) on fluvial bed sediments and the transport of solids. This research provided multiple evidence from field and laboratory observations and experiments that many species among mammals, amphibians, fish, insects, crustaceans, mollusks, and worms engineer bed sediments of running waters with diverse mechanistic "tools", thereby perturbing or consolidating the sediments in many types of running waters across continents, seasons, habitat types, particle sizes, and discharge levels (baseflow vs. flood). Furthermore, many animals modify the bed-sediment engineering by plants (algae, larger macrophytes, riparian vegetation). Modeling effects of bioturbating lotic animals across species and relatively simple environmental conditions (in mesocosms) provided highly significant results (P-range: < 10- 6- < 10- 15) for nine sediment variables describing baseflow and flood-induced sediment transport as well as sediment surface modifications. For example, bioturbator biomass and/or algal abundance in combination with physical variables, such as baseflow shear stress or gravel size, explained between ~ 70 and ~ 90% of the variability in sediment responses such as the overall baseflow sediment transport and, as a result of the baseflow sediment-surface engineering by the animals, the flood-induced gravel or sand transport. Confronting these seemingly encouraging experimental results with real world conditions, however, illustrates considerable problems to unravel the complexity of biotic and physical factors that vary temporally and interfere/interact non-linearly in a patchy pattern in small parts of real river beds, where baseflow bed-sediment engineering by lotic animals prevents or fosters mass erosion during subsequent floods. Despite these complications, these problems must be solved, as bioturbators such as crayfish and bioconsolidators such as silk-spinning caddisflies may locally modify (i) rates of transport of fluvial sediments over three orders of magnitude and (ii) frequencies of mass transport events over five orders of magnitude. The fastest way to identify promising subsequent research routes in this field would be through a variety of abundance manipulations of lotic organisms (animals and plants having different mechanistic sediment-engineering abilities) in real rivers in combination with a simple approach to assess the critical shear stress in situ for varying types of sediments. This would require joint research by fluvial geomorphologists, hydrologists, and ecologists.

  1. Facts and fiction of genetically engineered food.

    PubMed

    Batista, Rita; Oliveira, Maria Margarida

    2009-05-01

    The generation of genetically engineered (GE) foods has been raising several concerns and controversies that divide not only the general public but also the scientific community. The fear and importance of the new technology, as well as commercial interests, have supported many of the ongoing discussions. The recent increase in the number of GE foods approved for import into the European Union and the increasingly global commercial food trades justify revisiting the facts and fiction surrounding this technology with the aim of increasing public awareness for well-informed decisions. Techniques that have recently become available for assessing food quality and its impact on human health, as well as the wealth of scientific data previously generated, clearly support the safety of commercialized GE products. PMID:19324440

  2. Genetically engineered antibody molecules and their application.

    PubMed

    Morrison, S L; Wims, L; Wallick, S; Tan, L; Oi, V T

    1987-01-01

    Immunoglobulin genes can be efficiently expressed following transfection into myeloma cells. Using protoplast fusion, transfection frequencies greater than 10(-3) can be achieved. Compatible plasmids containing two different selectible markers are used to simultaneously deliver heavy and light chain genes to the same cell. To produce molecules with differing specificities the rearranged and expressed variable regions can be cloned from the appropriate hybridoma. In some cases, variable regions from cDNAs can be inserted into the expression vectors. It is possible to manipulate the immunoglobulin genes and produce novel antibody molecules. Antibodies have been produced in which the variable regions from mouse antibodies have been joined to human constant regions. In addition, antibodies with altered constant regions have been produced. These genetically engineered antibodies provide a unique set of reagents to study structure-function relationships within the molecule. They also can potentially be used in the diagnosis and therapy of human disease. PMID:3327412

  3. A comparative risk assessment of genetically engineered, mutagenic, and conventional wheat production systems

    E-print Network

    Peterson, Robert K. D.

    A comparative risk assessment of genetically engineered, mutagenic, and conventional wheat; accepted 27 July 2005 Key words: biotechnology, genetically engineered crops, GMO, herbicide exposure biotechnologies, such as genetic engineering and mutagenic techniques, have lagged behind other crop species

  4. 78 FR 13286 - Sharing Certain Business Information Regarding the Introduction of Genetically Engineered...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-27

    ...altered or produced through genetic engineering that are plant pests or that...Altered or Produced Through Genetic Engineering Which Are Plant Pests or...procedure, Biotechnology, Genetic engineering, Imports, Packaging...

  5. 76 FR 8707 - Syngenta Seeds, Inc.; Determination of Nonregulated Status for Corn Genetically Engineered To...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-15

    ...Corn Genetically Engineered To Produce an Enzyme That Facilitates Ethanol Production AGENCY...genetically engineered to produce a microbial enzyme that facilitates ethanol production...genetically engineered to produce a microbial enzyme that facilitates ethanol...

  6. Genospirituality: genetic engineering for spiritual and religious enhancement.

    PubMed

    Charlton, Bruce G

    2008-12-01

    The most frequently discussed role for genetic engineering is in relation to medicine, and a second area which provokes discussion is the use of genetic engineering as an enhancement technology. But one neglected area is the potential use of genetic engineering to increase human spiritual and religious experience - or genospirituality. If technologies are devised which can conveniently and safely engineer genes causal of spiritual and religious behaviours, then people may become able to choose their degree of religiosity or spiritual sensitivity. For instance, it may become possible to increase the likelihood of direct religious experience - i.e. 'revelation': the subjective experience of communication from the deity. Or, people may be able to engineer 'animistic' thinking, a mode of cognition in which the significant features of the world - such as large animals, trees, distinctive landscape features - are regarded as sentient and intentional beings; so that the individual experiences a personal relationship with the world. Another potentially popular spiritual ability would probably be shamanism; in which states of altered consciousness (e.g. trances, delirium or dreams) are induced and the shaman may undergo the experience of transformations, 'soul journeys' and contact with a spirit realm. Ideally, shamanistic consciousness could be modulated such that trances were self-induced only when wanted and when it was safe and convenient; and then switched-off again completely when full alertness and concentration are necessary. It seems likely that there will be trade-offs for increased spirituality; such as people becoming less 'driven' to seek status and monetary rewards - as a result of being more spiritually fulfilled people might work less hard and take more leisure. On the other hand, it is also possible that highly moral, altruistic, peaceable and principled behaviours might become more prevalent; and the energy and joyousness of the best churches might spread and be strengthened. Overall, genospirituality would probably be used by people who were unable to have the kind of spiritual or religious experiences which they wanted (or perhaps even needed) in order to lead the kind of life to which they aspired. PMID:18782654

  7. Agrobacterium: nature’s genetic engineer

    PubMed Central

    Nester, Eugene W.

    2015-01-01

    Agrobacterium was identified as the agent causing the plant tumor, crown gall over 100 years ago. Since then, studies have resulted in many surprising observations. Armin Braun demonstrated that Agrobacterium infected cells had unusual nutritional properties, and that the bacterium was necessary to start the infection but not for continued tumor development. He developed the concept of a tumor inducing principle (TIP), the factor that actually caused the disease. Thirty years later the TIP was shown to be a piece of a tumor inducing (Ti) plasmid excised by an endonuclease. In the next 20 years, most of the key features of the disease were described. The single-strand DNA (T-DNA) with the endonuclease attached is transferred through a type IV secretion system into the host cell where it is likely coated and protected from nucleases by a bacterial secreted protein to form the T-complex. A nuclear localization signal in the endonuclease guides the transferred strand (T-strand), into the nucleus where it is integrated randomly into the host chromosome. Other secreted proteins likely aid in uncoating the T-complex. The T-DNA encodes enzymes of auxin, cytokinin, and opine synthesis, the latter a food source for Agrobacterium. The genes associated with T-strand formation and transfer (vir) map to the Ti plasmid and are only expressed when the bacteria are in close association with a plant. Plant signals are recognized by a two-component regulatory system which activates vir genes. Chromosomal genes with pleiotropic functions also play important roles in plant transformation. The data now explain Braun’s old observations and also explain why Agrobacterium is nature’s genetic engineer. Any DNA inserted between the border sequences which define the T-DNA will be transferred and integrated into host cells. Thus, Agrobacterium has become the major vector in plant genetic engineering. PMID:25610442

  8. Genetic Engineering of Optical Properties of Biomaterials

    NASA Astrophysics Data System (ADS)

    Gourley, Paul; Naviaux, Robert; Yaffe, Michael

    2008-03-01

    Baker's yeast cells are easily cultured and can be manipulated genetically to produce large numbers of bioparticles (cells and mitochondria) with controllable size and optical properties. We have recently employed nanolaser spectroscopy to study the refractive index of individual cells and isolated mitochondria from two mutant strains. Results show that biomolecular changes induced by mutation can produce bioparticles with radical changes in refractive index. Wild-type mitochondria exhibit a distribution with a well-defined mean and small variance. In striking contrast, mitochondria from one mutant strain produced a histogram that is highly collapsed with a ten-fold decrease in the mean and standard deviation. In a second mutant strain we observed an opposite effect with the mean nearly unchanged but the variance increased nearly a thousand-fold. Both histograms could be self-consistently modeled with a single, log-normal distribution. The strains were further examined by 2-dimensional gel electrophoresis to measure changes in protein composition. All of these data show that genetic manipulation of cells represents a new approach to engineering optical properties of bioparticles.

  9. Genetically engineered mice in understanding the basis of neonatal lung disease.

    PubMed

    Glasser, Stephan W; Nogee, Lawrence M

    2006-12-01

    Advances in genetic engineering have allowed the creation of animals with additional or deleted genes. New genes may be inserted in mice, specific genes inactivated or "knocked out," and more complex animals created in which genes can be turned on or off at different times in development or in different tissues. These animal models allow for more detailed studies of the proteins encoded by the manipulated gene, an improved understanding of the pathophysiology of diseases resulting from the genetic alterations, and model organisms in which to study potential new therapies. Multiple mouse models involving genes important in surfactant production and regulation relevant to lung disease observed in human newborns have been created. This review will discuss the creation of such animals and illustrate their utility in understanding human disease. PMID:17142160

  10. Genetic Engineering and the Amelioration of Genetic Defect

    ERIC Educational Resources Information Center

    Lederberg, Joshua

    1970-01-01

    Discusses the claims for a brave new world of genetic manipulation" and concludes that if we could agree upon applying genetic (or any other effective) remedies to global problems we probably would need no rescourse to them. Suggests that effective methods of preventing genetic disease are prevention of mutations and detection and containment of…

  11. Towards Reverse Engineering of Genetic Regulatory Networks Zelmina Lubovac

    E-print Network

    Chang, Joseph T.

    1 Towards Reverse Engineering of Genetic Regulatory Networks Zelmina Lubovac , Björn Olsson understanding of reverse engineering of regulatory networks. One of the aspects that have not been considered to a great extent in the development of reverse engineering approaches is combinatorial regulation

  12. Natural genetic engineering: intelligence & design in evolution?

    PubMed Central

    2011-01-01

    There are many things that I like about James Shapiro's new book "Evolution: A View from the 21st Century" (FT Press Science, 2011). He begins the book by saying that it is the creation of novelty, and not selection, that is important in the history of life. In the presence of heritable traits that vary, selection results in the evolution of a population towards an optimal composition of those traits. But selection can only act on changes - and where does this variation come from? Historically, the creation of novelty has been assumed to be the result of random chance or accident. And yet, organisms seem 'designed'. When one examines the data from sequenced genomes, the changes appear NOT to be random or accidental, but one observes that whole chunks of the genome come and go. These 'chunks' often contain functional units, encoding sets of genes that together can perform some specific function. Shapiro argues that what we see in genomes is 'Natural Genetic Engineering', or designed evolution: "Thinking about genomes from an informatics perspective, it is apparent that systems engineering is a better metaphor for the evolutionary process than the conventional view of evolution as a select-biased random walk through limitless space of possible DNA configurations" (page 6). In this review, I will have a look at four topics: 1.) why I think genomics is not the whole story; 2.) my own perspective of E. coli genomics, and how I think it relates to this book; 3.) a brief discussion on "Intelligence, Design, and Evolution"; and finally, 4.) a section "in defense of the central dogma".

  13. The Genetic Engineering of Motor Proteins

    NASA Astrophysics Data System (ADS)

    Hartz, Rachael M.

    Molecular motors are a remarkable feature within living organisms that are responsible for directional mechanical motion, which is driven by adenosine triphosphate (ATP) hydrolysis. Actin-binding molecular motors are of specific interest in the field of nanotechnology as filamentous actin is capable of carrying cargo, such as quantum dots, while it is translocated along a motor coated surface. The binding regions of motor proteins, which are known to interact with actin, such as Myosin, have been thoroughly examined and identified. Rapid genetic engineering of the ATP-hydrolyzing enzyme, adenosine kinase, to incorporate these binding regions is possible through the use of site- directed mutagenesis. The sequences, which were mutated into the ADK wt gene, were incorporated in an unstructured loop region. During the phosphate transfer, the mutants switch between open and closed conformational states. The binding affinity of the sequences to the actin is altered during this conformational switch, thus causing the motor to move along actin filament. The ADK mutants and their interaction with filamentous actin was monitored by an in vitro motility assay. Two different mutants of ADK were found to have retained enzymatic functionality after the mutagenesis as well as function as actin-based motor proteins.

  14. Antimicrobial functionalized genetically engineered spider silk

    PubMed Central

    Gomes, Sílvia; Leonor, Isabel B.; Mano, João F.; Reis, Rui L.; Kaplan, David L.

    2011-01-01

    Genetically engineered fusion proteins offer potential as multifunctional biomaterials for medical use. Fusion or chimeric proteins can be formed using recombinant DNA technology by combining nucleotide sequences encoding different peptides or proteins that are otherwise not found together in nature. In the present study, three new fusion proteins were designed, cloned and expressed and assessed for function, by combining the consensus sequence of dragline spider silk with three different antimicrobial peptides. The human antimicrobial peptides human neutrophil defensin 2 (HNP-2), human neutrophil defensins 4 (HNP-4) and hepcidin were fused to spider silk through bioengineering. The spider silk domain maintained its self-assembly features, a key aspect of these new polymeric protein biomaterials, allowing the formation of ?-sheets to lock in structures via physical interactions without the need for chemical cross-linking. These new functional silk proteins were assessed for antimicrobial activity against Gram - Escherichia coli and Gram + Staphylococcus aureus and microbicidal activity was demonstrated. Dynamic light scattering was used to assess protein aggregation to clarify the antimicrobial patterns observed. Attenuated-total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) and circular dichroism (CD) were used to assess the secondary structure of the new recombinant proteins. In vitro cell studies with a human osteosarcoma cell line (SaOs-2) demonstrated the compatibility of these new proteins with mammalian cells. PMID:21458065

  15. Disentangling Genetic Variation for Resistance and Tolerance to Infectious Diseases in Animals 

    E-print Network

    Råberg, Lars; Sim, Derek; Read, Andrew F

    Hosts can in principle employ two different strategies to defend themselves against parasites: resistance and tolerance. Animals typically exhibit considerable genetic variation for resistance (the ability to limit parasite burden). However, little...

  16. Modeling the Diagnostic Criteria for Alcohol Dependence with Genetic Animal Models

    PubMed Central

    Kendler, Kenneth S.; Hitzemann, Robert J.

    2012-01-01

    A diagnosis of alcohol dependence (AD) using the DSM-IV-R is categorical, based on an individual’s manifestation of three or more symptoms from a list of seven. AD risk can be traced to both genetic and environmental sources. Most genetic studies of AD risk implicitly assume that an AD diagnosis represents a single underlying genetic factor. We recently found that the criteria for an AD diagnosis represent three somewhat distinct genetic paths to individual risk. Specifically, heavy use and tolerance versus withdrawal and continued use despite problems reflected separate genetic factors. However, some data suggest that genetic risk for AD is adequately described with a single underlying genetic risk factor. Rodent animal models for alcohol-related phenotypes typically target discrete aspects of the complex human AD diagnosis. Here, we review the literature derived from genetic animal models in an attempt to determine whether they support a single-factor or multiple-factor genetic structure. We conclude that there is modest support in the animal literature that alcohol tolerance and withdrawal reflect distinct genetic risk factors, in agreement with our human data. We suggest areas where more research could clarify this attempt to align the rodent and human data. PMID:21910077

  17. Genetically engineered phage fibers and coatings for antibacterial applications

    E-print Network

    Mao, Joan Y

    2009-01-01

    Multifunctionality can be imparted to protein-based fibers and coatings via either synthetic or biological approaches. Here, we demonstrate potent antimicrobial functionality of genetically engineered, phage-based fibers ...

  18. "Genetic Engineering" Gains Momentum (Science/Society Case Study).

    ERIC Educational Resources Information Center

    Moore, John W.; Moore, Elizabeth A., Eds.

    1980-01-01

    Reviews the benefits and hazards of genetic engineering, or "recombinant-DNA" research. Recent federal safety rules issued by NIH which ease the strict prohibitions on recombinant-DNA research are explained. (CS)

  19. Direct bioelectrocatalysis at the interfaces by genetically engineered dehydrogenase

    E-print Network

    Yucesoy, Deniz Tanil; Karaca, Banu Taktak; Cetinel, Sibel; Caliskan, Huseyin Burak; Adali, Esref; Gul-Karaguler, Nevin; Tamerler, Candan

    2014-12-13

    harvesting systems requires controlled orientation and organisation of the proteins at the inorganic interfaces. Herein, the authors take the initial steps towards designing multifunctional, enzyme-based platforms by genetically integrating the engineered...

  20. Virus resistant plums through genetic engineering - from lab to market

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Genetic engineering (GE) has the potential to revolutionize the genetic improvement of fruit trees and other specialty crops, to provide greater flexibility and speed in responding to changes in climate, production systems and market demands, and to maintain the competitiveness of American agricultu...

  1. New Constitutive Vectors: Useful Genetic Engineering Tools for Biocatalysis

    PubMed Central

    Xu, Youqiang; Tao, Fei; Xu, Ping

    2013-01-01

    Constitutive vectors are useful tools for genetic engineering. Two constitutive vectors with high levels of expression and broad host ranges were developed and used in a range of Pseudomonas hosts. The vectors showed superior characteristics compared to the inducible vectors as well as the potential to be used as improved genetic tools for biocatalysis. PMID:23416993

  2. The Utility of Genetically Modified Animals in Modeling OCD-Spectrum Disorders

    E-print Network

    Kalueff, Allan V.

    139 Chapter 7 The Utility of Genetically Modified Animals in Modeling OCD-Spectrum Disorders AmandaPorte, and Allan V. Kalueff Abstract Obsessive-compulsive disorder (OCD) inflicts uncontrollable, intrusive mechanisms responsible for this disorder. While its exact pathogenesis remains unknown, genetic factors also

  3. Teacher-to-Teacher: An Annotated Bibliography on DNA and Genetic Engineering.

    ERIC Educational Resources Information Center

    Mertens, Thomas R., Comp.

    1984-01-01

    Presented is an annotated bibliography of 24 books on DNA and genetic engineering. Areas considered in these books include: basic biological concepts to help understand advances in genetic engineering; applications of genetic engineering; social, legal, and moral issues of genetic engineering; and historical aspects leading to advances in…

  4. The ecological risks of genetically engineered organisms

    NASA Astrophysics Data System (ADS)

    Wolfenbarger, Lareesa

    2001-03-01

    Highly publicized studies have suggested environmental risks of releasing genetically engineered organisms (GEOs) and have renewed concerns over the evaluation and regulation of these products in domestic and international arenas. I present an overview of the risks of GEOs and the available evidence addressing these and discuss the challenges for risk assessment. Main categories of risk include non-target effects from GEOs, emergence of new viral diseases, and the spread of invasive (weedy) characteristics. Studies have detected non-target effects in some cases but not all; however, much less information exists on other risks, in part due to a lack of conceptual knowledge. For example, general models for predicting invasiveness are not well developed for any introduced organism. The risks of GEOs appear comparable to those for any introduced species or organism, but the magnitude of the risk or the pathway of exposure to the risk can differ among introduced organisms. Therefore, assessing the risks requires a case-by-case analysis so that any differences can be identified. Challenges to assessing risks to valued ecosystems include variability in effects and ecosystem complexity. Ecosystems are a dynamic and complex network of biological and physical interactions. Introducing a new biological entity, such as a GEO, may potentially alter any of these interactions, but evaluating all of these is unrealistic. Effects on a valued ecosystem could vary greatly depending on the geographical location of the experimental site, the GEO used, the plot size of the experiment (scaling effects), and the biological and physical parameters used in the experiment. Experiments that address these sources of variability will provide the most useful information for risk assessments.

  5. Chapter VIII. Contributions of propagation techniques and genetic modification to breeding - genetic engineering for disease resistance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Genetic engineering offers an opportunity to develop flower bulb crops with resistance to fungal, viral, and bacterial pathogens. Several of the flower bulb crops, Lilium spp., Gladiolus, Zantedeschia, Muscari, Hyacinthus, Narcissus, Ornithogalum, Iris, and Alstroemeria, have been transformed with t...

  6. Genetically Engineered Mouse Models for Studying Inflammatory Bowel Disease

    PubMed Central

    Mizoguchi, Atsushi; Takeuchi, Takahito; Himuro, Hidetomo; Okada, Toshiyuki; Mizoguchi, Emiko

    2015-01-01

    Inflammatory bowel disease (IBD) is a chronic intestinal inflammatory condition that is mediated by very complex mechanisms controlled by genetic, immune, and environmental factors. More than 74 kinds of genetically engineered mouse strains have been established since 1993 for studying IBD. Although mouse models cannot fully reflect human IBD, they have provided significant contributions for not only understanding the mechanism, but also developing new therapeutic means for IBD. Indeed, 20 kinds of genetically engineered mouse models carry the susceptibility genes identified in human IBD, and the functions of some other IBD susceptibility genes have also been dissected out using mouse models. Cutting-edge technologies such as cell-specific and inducible knockout systems, which were recently employed to mouse IBD models, have further enhanced the ability of investigators to provide important and unexpected rationales for developing new therapeutic strategies for IBD. In this review article, we briefly introduce 74 kinds of genetically engineered mouse models that spontaneously develop intestinal inflammation. PMID:26387641

  7. Xylitol Production by Genetically Engineered Trichoderma reesei Strains Using Barley Straw

    E-print Network

    Qin, Wensheng

    Xylitol Production by Genetically Engineered Trichoderma reesei Strains Using Barley Straw. The xylitol production by T. reesei can be enhanced by genetic engineering of blocking further xylitol and Microbiology, Institute of Chemical Engineering, Vienna University of Technology, Vienna, Austria e

  8. Perspective on Models in Theoretical and Practical Traditions of Knowledge: The Example of Otto Engine Animations

    ERIC Educational Resources Information Center

    Haglund, Jesper; Stromdahl, Helge

    2012-01-01

    Nineteen informants (n = 19) were asked to study and comment two computer animations of the Otto combustion engine. One animation was non-interactive and realistic in the sense of depicting a physical engine. The other animation was more idealised, interactive and synchronised with a dynamic PV-graph. The informants represented practical and…

  9. Reverse engineering of genetic networks through multicriterion optimization

    NASA Astrophysics Data System (ADS)

    van Someren, Eugene P.; Wessels, Lodewyk F. A.; Reinders, Marcel J. T.; Backer, Eric

    2002-06-01

    A major problem associated with the reverse engineering of genetic networks from micro-array data is how to reliably find genetic interactions when faced with a relatively small number of arrays compared to the number of genes. To cope with this dimensionality problem, it is imperative to employ additional (biological) knowledge about genetic networks, such as limited connectivity, redundancy, stability and robustness, to sensibly constrain the modeling process. Recently, we have shown that by applying single criteria, the inference of genetic interactions under realistic conditions can be significantly improved. In this paper, we study the problem of how to combine constraints by formulating it as a multi-criterion optimization problem.

  10. Prospects for Genetic Engineering in Plants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Genetically modified plants now constitute a significant portion of the worlds agricultural output. Genetically modified corn, soybean, canola, rice, and cotton are being adopted by growers in both industrialized and developing nations at an increasing rate. The most popular products have been eng...

  11. Genetic and somatic effects in animals maintained on tritiated water

    SciTech Connect

    Carsten, A.L.; Brooks, A.; Commerford, S.L.; Cronkite, E.P.

    1981-01-01

    The possible genetic (dominant lethal mutations (DLM) and cytogenetic changes in the regenerating liver) and somatic (hematopoietic stem cell changes, growth and nonspecific life time shortening) effects in mice maintained on tritiated water (HTO) over two generations was investigated. Results to date are summarized. (ACR)

  12. A molecular genetic approach for forensic animal species identification.

    PubMed

    Bellis, C; Ashton, K J; Freney, L; Blair, B; Griffiths, L R

    2003-07-01

    This study investigated potential markers within chromosomal, mitochondrial DNA (mtDNA) and ribosomal RNA (rRNA) with the aim of developing a DNA based method to allow differentiation between animal species. Such discrimination tests may have important applications in the forensic science, agriculture, quarantine and customs fields. DNA samples from five different animal individuals within the same species for 10 species of animal (including human) were analysed. DNA extraction and quantitation followed by PCR amplification and GeneScan visualisation formed the basis of the experimental analysis. Five gene markers from three different types of genes were investigated. These included genomic markers for the beta-actin and TP53 tumor suppressor gene. Mitochondrial DNA markers, designed by Bataille et al. [Forensic Sci. Int. 99 (1999) 165], examined the Cytochrome b gene and Hypervariable Displacement Loop (D-Loop) region. Finally, a ribosomal RNA marker for the 28S rRNA gene optimised by Naito et al. [J. Forensic Sci. 37 (1992) 396] was used as a possible marker for speciation. Results showed a difference of only several base pairs between all species for the beta-actin and 28S markers, with the exception of Sus scrofa (pig) beta-actin fragment length, which produced a significantly smaller fragment. Multiplexing of Cytochrome b and D-Loop markers gave limited species information, although positive discrimination of human DNA was evident. The most specific and discriminatory results were shown using the TP53 gene since this marker produced greatest fragment size differences between animal species studied. Sample differentiation for all species was possible following TP53 amplification, suggesting that this gene could be used as a potential animal species identifier. PMID:12850402

  13. Genetic Programming for Reverse Engineering Mark Harman, William B. Langdon and Westley Weimer

    E-print Network

    Harman, Mark

    Genetic Programming for Reverse Engineering Mark Harman, William B. Langdon and Westley Weimer of Genetic Programming (GP) and Genetic Improvement (GI) to reverse engineering. Section II presents that form part of a `GP4RE' research agenda; genetic programming applications for reverse engineering. II

  14. 76 FR 39812 - Scotts Miracle-Gro Co.; Regulatory Status of Kentucky Bluegrass Genetically Engineered for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-07

    ... Organisms and Products Altered or Produced Through Genetic Engineering Which Are Plant Pests or Which There... produced through genetic engineering that are plant pests or that there is reason to believe are plant...' GE Kentucky bluegrass was also genetically engineered using genetic material from rice (Oryza...

  15. TMTI Task 1.6 Genetic Engineering Methods and Detection

    SciTech Connect

    Slezak, T; Lenhoff, R; Allen, J; Borucki, M; Vitalis, E; Gardner, S

    2009-12-04

    A large number of GE techniques can be adapted from other microorganisms to biothreat bacteria and viruses. Detection of GE in a microorganism increases in difficulty as the size of the genetic change decreases. In addition to the size of the engineered change, the consensus genomic sequence of the microorganism can impact the difficulty of detecting an engineered change in genomes that are highly variable from strain to strain. This problem will require comprehensive databases of whole genome sequences for more genetically variable biothreat bacteria and viruses. Preliminary work with microarrays for detecting synthetic elements or virulence genes and analytic bioinformatic approaches for whole genome sequence comparison to detect genetic engineering show promise for attacking this difficult problem but a large amount of future work remains.

  16. [Research progress of genetic engineering on medicinal plants].

    PubMed

    Teng, Zhong-qiu; Shen, Ye

    2015-02-01

    The application of genetic engineering technology in modern agriculture shows its outstanding role in dealing with food shortage. Traditional medicinal plant cultivation and collection have also faced with challenges, such as lack of resources, deterioration of environment, germplasm of recession and a series of problems. Genetic engineering can be used to improve the disease resistance, insect resistance, herbicides resistant ability of medicinal plant, also can improve the medicinal plant yield and increase the content of active substances in medicinal plants. Thus, the potent biotechnology can play an important role in protection and large area planting of medicinal plants. In the development of medicinal plant genetic engineering, the safety of transgenic medicinal plants should also be paid attention to. A set of scientific safety evaluation and judgment standard which is suitable for transgenic medicinal plants should be established based on the recognition of the particularity of medicinal plants. PMID:26137675

  17. Genetic engineering of human pluripotent cells using TALE nucleases.

    PubMed

    Hockemeyer, Dirk; Wang, Haoyi; Kiani, Samira; Lai, Christine S; Gao, Qing; Cassady, John P; Cost, Gregory J; Zhang, Lei; Santiago, Yolanda; Miller, Jeffrey C; Zeitler, Bryan; Cherone, Jennifer M; Meng, Xiangdong; Hinkley, Sarah J; Rebar, Edward J; Gregory, Philip D; Urnov, Fyodor D; Jaenisch, Rudolf

    2011-08-01

    Targeted genetic engineering of human pluripotent cells is a prerequisite for exploiting their full potential. Such genetic manipulations can be achieved using site-specific nucleases. Here we engineered transcription activator-like effector nucleases (TALENs) for five distinct genomic loci. At all loci tested we obtained human embryonic stem cell (ESC) and induced pluripotent stem cell (iPSC) clones carrying transgenic cassettes solely at the TALEN-specified location. Our data suggest that TALENs employing the specific architectures described here mediate site-specific genome modification in human pluripotent cells with similar efficiency and precision as do zinc-finger nucleases (ZFNs). PMID:21738127

  18. Current development in genetic engineering strategies of Bacillus species.

    PubMed

    Dong, Huina; Zhang, Dawei

    2014-01-01

    The complete sequencing and annotation of the genomes of industrially-important Bacillus species has enhanced our understanding of their properties, and allowed advances in genetic manipulations in other Bacillus species. Post-genomic studies require simple and highly efficient tools to enable genetic manipulation. Here, we summarize the recent progress in genetic engineering strategies for Bacillus species. We review the available genetic tools that have been developed in Bacillus species, as well as methods developed in other species that may also be applicable in Bacillus. Furthermore, we address the limitations and challenges of the existing methods, and discuss the future research prospects in developing novel and useful tools for genetic modification of Bacillus species. PMID:24885003

  19. Current development in genetic engineering strategies of Bacillus species

    PubMed Central

    2014-01-01

    The complete sequencing and annotation of the genomes of industrially-important Bacillus species has enhanced our understanding of their properties, and allowed advances in genetic manipulations in other Bacillus species. Post-genomic studies require simple and highly efficient tools to enable genetic manipulation. Here, we summarize the recent progress in genetic engineering strategies for Bacillus species. We review the available genetic tools that have been developed in Bacillus species, as well as methods developed in other species that may also be applicable in Bacillus. Furthermore, we address the limitations and challenges of the existing methods, and discuss the future research prospects in developing novel and useful tools for genetic modification of Bacillus species. PMID:24885003

  20. Cryoconservation of animal genetic resources. Animal Production and Health Guidelines No. 12

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Livestock agriculture is in a period of tumultuous change and upheaval. General economic development, and population growth and mobility, have increased demand for livestock products, but have also placed pressures on the sustainability of rural environments and animal production systems. Livestock ...

  1. The animal genetic resource information network (AnimalGRIN) database: A database design and implementation case

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This manuscript presents a case study that is based on an actual project for the United States Department of Agriculture’s National Animal Germplasm Program (NAGP). The NAGP collects, preserves, and documents germplasm from various breeds of livestock in the United States, in order to preserve and e...

  2. The Animal Genetic Resource Information Network (AnimalGRIN) Database: A Database Design & Implementation Case

    ERIC Educational Resources Information Center

    Irwin, Gretchen; Wessel, Lark; Blackman, Harvey

    2012-01-01

    This case describes a database redesign project for the United States Department of Agriculture's National Animal Germplasm Program (NAGP). The case provides a valuable context for teaching and practicing database analysis, design, and implementation skills, and can be used as the basis for a semester-long team project. The case demonstrates the…

  3. GENETICALLY ENGINEERED CROPS WITH RESISTANCE TO INSECTS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Genetic transformation technology allows genes to be moved across species, greatly improving the opportunities to breed plants for insect control. The Cry1Ac protein in cotton, Gossypium hirsutum L., was registered by Monsanto as Bollgard, and targeted to tobacco budworm, Heliothis virescens (Fab),...

  4. Genetic engineering of sulfur-degrading Sulfolobus

    SciTech Connect

    Ho, N.W.Y.

    1991-01-01

    The objectives of the proposed research is to first establish a plasmid-mediated genetic transformation system for the sulfur degrading Sulfolobus, and then to clone and overexpress the genes encoding the organic-sulfur-degrading enzymes from Sulfolobus- as well as from other microorganisms, to develop a Sulfolobus-based microbial process for the removal of both organic and inorganic sulfur from coal.

  5. GENETIC ENGINEERING OF ENHANCED MICROBIAL NITRIFICATION

    EPA Science Inventory

    Experiments were conducted to introduce genetic information in the form of antibiotic or mercuric ion resistance genes into Nitrobacter hamburgensis strain X14. The resistance genes were either stable components of broad host range plasmids or transposable genes on methods for p...

  6. The use of whole food animal studies in the safety assessment of genetically modified crops: Limitations and recommendations

    PubMed Central

    Bartholomaeus, Andrew; Parrott, Wayne; Bondy, Genevieve

    2013-01-01

    There is disagreement internationally across major regulatory jurisdictions on the relevance and utility of whole food (WF) toxicity studies on GM crops, with no harmonization of data or regulatory requirements. The scientific value, and therefore animal ethics, of WF studies on GM crops is a matter addressable from the wealth of data available on commercialized GM crops and WF studies on irradiated foods. We reviewed available GM crop WF studies and considered the extent to which they add to the information from agronomic and compositional analyses. No WF toxicity study was identified that convincingly demonstrated toxicological concern or that called into question the adequacy, sufficiency, and reliability of safety assessments based on crop molecular characterization, transgene source, agronomic characteristics, and/or compositional analysis of the GM crop and its near-isogenic line. Predictions of safety based on crop genetics and compositional analyses have provided complete concordance with the results of well-conducted animal testing. However, this concordance is primarily due to the improbability of de novo generation of toxic substances in crop plants using genetic engineering practices and due to the weakness of WF toxicity studies in general. Thus, based on the comparative robustness and reliability of compositional and agronomic considerations and on the absence of any scientific basis for a significant potential for de novo generation of toxicologically significant compositional alterations as a sole result of transgene insertion, the conclusion of this review is that WF animal toxicity studies are unnecessary and scientifically unjustifiable. PMID:24164514

  7. Arsenite cocarcinogenesis: an animal model derived from genetic toxicology studies.

    PubMed Central

    Rossman, Toby G; Uddin, Ahmed N; Burns, Fredric J; Bosland, Maarten C

    2002-01-01

    Although epidemiologic evidence shows an association between inorganic arsenic in drinking water and increased risk of skin, lung, and bladder cancers, no animal model for arsenic carcinogenesis has been successful. This lack has hindered mechanistic studies of arsenic carcinogenesis. Previously, we and others found that low concentrations (< or =5 microm) of arsenite (the likely environmental carcinogen), which are not mutagenic, can enhance the mutagenicity of other agents, including ultraviolet radiation (UVR) and alkylating agents. This enhancing effect appears to result from inhibition of DNA repair by arsenite, but not via inhibition of DNA repair enzymes. Rather, low concentrations of arsenite disrupt p53 function and upregulate cyclin D1. Failure to find an animal model for arsenic carcinogenesis might be because arsenite is not a carcinogen per se but acts as an enhancing agent (cocarcinogen) with a genotoxic partner. We tested this hypothesis with solar UVR in hairless but immunocompetent Skh1 mice. Mice were given 10 mg/L sodium arsenite in drinking water (or not) and irradiated with 1.7 KJ/m(2) solar UVR 3 times weekly. As expected, no tumors appeared in any organs in control mice or in mice given arsenite alone. After 26 weeks irradiated mice given arsenite had a 2.4-fold increase in skin tumor yield compared with mice given UVR alone. The tumors were mostly squamous cell carcinomas, and those occurring in mice given UVR plus arsenite were much larger and more invasive. These results are consistent with the hypothesis that arsenic acts as a cocarcinogen with a second (genotoxic) agent by inhibiting DNA repair and/or enhancing positive growth signaling. Skin cancers in populations drinking water containing arsenic may be caused by the enhancement by arsenic compounds of carcinogenesis induced by UVR (or other environmental agents). It is possible that lung and bladder cancers associated with arsenic in drinking water may also require a carcinogenic partner. PMID:12426125

  8. Regulatory steps associated with use of value-added recombinant proteins and peptides screened in high-throughput for expression in genetically engineered starch and cellulosic fuel ethanol yeast strains

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Recombinant proteins expressed in animals have been a public concern as a perceived risk to the consumer. Animals are currently being treated with genetically engineered biologicals, such as growth hormone, or fed genetically modified plants. Similarly, various commercially-valuable proteins or pe...

  9. Grant Patents on Animals? An Ethical and Legal Battle Looms.

    ERIC Educational Resources Information Center

    Wheeler, David L.

    1987-01-01

    Rulings on applications for animal patents being considered by the U.S. Patent and Trademark Office could profoundly influence university patent and research income. Many animal-rights advocates have expressed philosophical objections to genetic engineering of animals. (MLW)

  10. Genetically Engineered Materials for Biofuels Production

    NASA Astrophysics Data System (ADS)

    Raab, Michael

    2012-02-01

    Agrivida, Inc., is an agricultural biotechnology company developing industrial crop feedstocks for the fuel and chemical industries. Agrivida's crops have improved processing traits that enable efficient, low cost conversion of the crops' cellulosic components into fermentable sugars. Currently, pretreatment and enzymatic conversion of the major cell wall components, cellulose and hemicellulose, into fermentable sugars is the most expensive processing step that prevents widespread adoption of biomass in biofuels processes. To lower production costs we are consolidating pretreatment and enzyme production within the crop. In this strategy, transgenic plants express engineered cell wall degrading enzymes in an inactive form, which can be reactivated after harvest. We have engineered protein elements that disrupt enzyme activity during normal plant growth. Upon exposure to specific processing conditions, the engineered enzymes are converted into their active forms. This mechanism significantly lowers pretreatment costs and enzyme loadings (>75% reduction) below those currently available to the industry.

  11. Genetic Improvement for Adaptive Software Engineering Mark Harman, Yue Jia, William B. Langdon, Justyna Petke, Iman Hemati Moghadam,

    E-print Network

    Fernandez, Thomas

    Genetic Improvement for Adaptive Software Engineering Mark Harman, Yue Jia, William B. Langdon Learning, Genetic Improve- ment, Search Based Software Engineering 1. INTRODUCTION Many Artificial Engineering approach called `genetic improvement' could be extended to provide online adaptivity. Search Based

  12. The role of genetically engineered pigs in xenotransplantation research.

    PubMed

    Cooper, David Kc; Ekser, Burcin; Ramsoondar, Jagdeece; Phelps, Carol; Ayares, David

    2016-01-01

    There is a critical shortage in the number of deceased human organs that become available for the purposes of clinical transplantation. This problem might be resolved by the transplantation of organs from pigs genetically engineered to protect them from the human immune response. The pathobiological barriers to successful pig organ transplantation in primates include activation of the innate and adaptive immune systems, coagulation dysregulation and inflammation. Genetic engineering of the pig as an organ source has increased the survival of the transplanted pig heart, kidney, islet and corneal graft in non-human primates (NHPs) from minutes to months or occasionally years. Genetic engineering may also contribute to any physiological barriers that might be identified, as well as to reducing the risks of transfer of a potentially infectious micro-organism with the organ. There are now an estimated 40 or more genetic alterations that have been carried out in pigs, with some pigs expressing five or six manipulations. With the new technology now available, it will become increasingly common for a pig to express even more genetic manipulations, and these could be tested in the pig-to-NHP models to assess their efficacy and benefit. It is therefore likely that clinical trials of pig kidney, heart and islet transplantation will become feasible in the near future. Copyright © 2015 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. PMID:26365762

  13. Genetic engineering of syringyl-enriched lignin in plants

    DOEpatents

    Chiang, Vincent Lee; Li, Laigeng

    2004-11-02

    The present invention relates to a novel DNA sequence, which encodes a previously unidentified lignin biosynthetic pathway enzyme, sinapyl alcohol dehydrogenase (SAD) that regulates the biosynthesis of syringyl lignin in plants. Also provided are methods for incorporating this novel SAD gene sequence or substantially similar sequences into a plant genome for genetic engineering of syringyl-enriched lignin in plants.

  14. Genetic Engineering--A Lesson on Bioethics for the Classroom.

    ERIC Educational Resources Information Center

    Armstrong, Kerri; Weber, Kurt

    1991-01-01

    A unit designed to cover the topic of genetic engineering and its ethical considerations is presented. Students are expected to learn the material while using a debate format. A list of objectives for the unit, the debate format, and the results from an opinion questionnaire are described. (KR)

  15. GENETIC ENGINEERING AND THE DEVELOPMENT OF NEW POLLUTION CONTROL TECHNOLOGIES

    EPA Science Inventory

    This report relates genetic engineering and biological waste treatment, so that opportunities for its improvement can be identified and evaluated. It describes the state of development of gene manipulation and natural limits to biodegradation as of early 1983. It identifies a num...

  16. A Simple Interactive Introduction to Teaching Genetic Engineering

    ERIC Educational Resources Information Center

    Child, Paula

    2013-01-01

    In the UK, at key stage 4, students aged 14-15 studying GCSE Core Science or Unit 1 of the GCSE Biology course are required to be able to describe the process of genetic engineering to produce bacteria that can produce insulin. The simple interactive introduction described in this article allows students to consider the problem, devise a model and…

  17. Genetically Engineered Nanofiber-Like Viruses For Tissue Regenerating

    E-print Network

    Lee, Seung-Wuk

    Genetically Engineered Nanofiber-Like Viruses For Tissue Regenerating Materials Anna Merzlyak matrices at the nanometer scale is of great importance to the functional design of tissue regenerating challenging medical problems, such as nerve tissue regeneration after spinal cord injuries, or as in vitro

  18. GENETIC ENGINEERING OF PEANUT FOR REDUCTION OF AFLATOXIN CONTAMINATION

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Through genetic engineering of peanut, we have focused mainly on two levels of protection against aflatoxin contamination: the entry of spores through insect-damaged tissues and the growth of the fungus after entry, although interfering with the aflatoxin biosynthetic pathway also is of interest. T...

  19. Current Progress of Genetically Engineered Pig Models for Biomedical Research

    PubMed Central

    Gün, Gökhan

    2014-01-01

    Abstract The first transgenic pigs were generated for agricultural purposes about three decades ago. Since then, the micromanipulation techniques of pig oocytes and embryos expanded from pronuclear injection of foreign DNA to somatic cell nuclear transfer, intracytoplasmic sperm injection-mediated gene transfer, lentiviral transduction, and cytoplasmic injection. Mechanistically, the passive transgenesis approach based on random integration of foreign DNA was developed to active genetic engineering techniques based on the transient activity of ectopic enzymes, such as transposases, recombinases, and programmable nucleases. Whole-genome sequencing and annotation of advanced genome maps of the pig complemented these developments. The full implementation of these tools promises to immensely increase the efficiency and, in parallel, to reduce the costs for the generation of genetically engineered pigs. Today, the major application of genetically engineered pigs is found in the field of biomedical disease modeling. It is anticipated that genetically engineered pigs will increasingly be used in biomedical research, since this model shows several similarities to humans with regard to physiology, metabolism, genome organization, pathology, and aging. PMID:25469311

  20. Options and legal requirements for national and regional animal genetic resources collections

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The contraction of animal genetic resources on a global scale has motivated countries to establish gene banks as a mechanism to conserve national resources. Gene banks should establish a set of policies that insure they are complying with national laws. The two primary areas of consideration are ho...

  1. Engineering Redox-Sensitive Linkers for Genetically Encoded FRET-Based

    E-print Network

    Kenis, Paul J. A.

    Engineering Redox-Sensitive Linkers for Genetically Encoded FRET-Based Biosensors VLADIMIR LPhysics, §Chemical & Biomolecular Engineering, jjPathobiology, { Division of Nutritional Sciences, and #Center tool for studying normal cell proliferation, differentiation, and apoptosis. Genet- ically encoded

  2. 78 FR 66891 - Monsanto Co.; Determination of Nonregulated Status of Soybean Genetically Engineered for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-07

    ...Organisms and Products Altered or Produced Through Genetic Engineering Which Are Plant Pests or Which There Is Reason to...organisms and products altered or produced through genetic engineering that are plant pests or that there is reason...

  3. 76 FR 78232 - Monsanto Co.; Determination of Nonregulated Status for Soybean Genetically Engineered To Have a...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-16

    ...Organisms and Products Altered or Produced Through Genetic Engineering Which Are Plant Pests or Which There Is Reason to...organisms and products altered or produced through genetic engineering that are plant pests or that there is reason...

  4. 78 FR 13302 - Syngenta Biotechnology, Inc.; Determination of Nonregulated Status of Corn Genetically Engineered...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-27

    ...Organisms and Products Altered or Produced Through Genetic Engineering Which Are Plant Pests or Which There Is Reason to...organisms and products altered or produced through genetic engineering that are plant pests or that there is reason...

  5. 76 FR 63279 - Monsanto Co.; Determination of Nonregulated Status for Soybean Genetically Engineered for Insect...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-12

    ...Organisms and Products Altered or Produced Through Genetic Engineering Which Are Plant Pests or Which There Is Reason to...organisms and products altered or produced through genetic engineering that are plant pests or that there is reason...

  6. 77 FR 41350 - Monsanto Co.; Determination of Nonregulated Status of Soybean Genetically Engineered To Produce...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-13

    ...Organisms and Products Altered or Produced Through Genetic Engineering Which Are Plant Pests or Which There Is Reason to...organisms and products altered or produced through genetic engineering that are plant pests or that there is reason...

  7. 76 FR 80869 - Monsanto Co.; Determination of Nonregulated Status of Corn Genetically Engineered for Drought...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-27

    ...Organisms and Products Altered or Produced Through Genetic Engineering Which Are Plant Pests or Which There Is Reason to...organisms and products altered or produced through genetic engineering that are plant pests or that there is reason...

  8. 76 FR 39812 - Scotts Miracle-Gro Co.; Regulatory Status of Kentucky Bluegrass Genetically Engineered for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-07

    ...Organisms and Products Altered or Produced Through Genetic Engineering Which Are Plant Pests or Which There Is Reason to...organisms and products altered or produced through genetic engineering that are plant pests or that there is reason...

  9. 76 FR 5780 - Determination of Regulated Status of Alfalfa Genetically Engineered for Tolerance to the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-02

    ...Organisms and Products Altered or Produced Through Genetic Engineering Which Are Plant Pests or Which There Is Reason to...organisms and products altered or produced through genetic engineering that are plant pests or that there is reason...

  10. Engineering design optimization using species-conserving genetic algorithms

    NASA Astrophysics Data System (ADS)

    Li, Jian-Ping; Balazs, M. E.; Parks, G. T.

    2007-03-01

    The species conservation technique described here, in which the population of a genetic algorithm is divided into several groups according to their similarity, is inspired by ecology. Each group with similar characteristics is called a species and is centred on a dominating individual, called the species seed. A genetic algorithm based on this species conservation technique, called the species-conserving genetic algorithm (SCGA), was established and has been proved to be effective in finding multiple solutions of multimodal optimization problems. In this article, the SCGA is used to solve engineering design optimization problems. Different distance measures (measures of similarity) are investigated to analyse the performance of the SCGA. It is shown that the Euclidean distance is not the only possible basis for defining a species and sometimes may not make sense in engineering applications. Two structural design problems are used to demonstrate how the choice of a meaningful measure of similarity will help the exploration for significant designs.

  11. Reversible Hydrogels from Self-Assembling Genetically Engineered Protein Block Copolymers

    E-print Network

    Breedveld, Victor

    Reversible Hydrogels from Self-Assembling Genetically Engineered Protein Block Copolymers Chunyu Xu-soluble polyelectrolyte segment flanked by two coiled-coil domains was synthesized by genetic engineering methods antibodies that can form complexes with antigens,20 and genetically engineered proteins containing coiled

  12. The pedestrian watchmaker: Genetic clocks from engineered oscillators Natalie A. Cookson a

    E-print Network

    Hasty, Jeff

    Review The pedestrian watchmaker: Genetic clocks from engineered oscillators Natalie A. Cookson and indus- trial pursuits that now includes all of genetic engineering. While the watchmaker analogy does the connection of engineered components in a controlled physical environment. Genetic circuits, on the other hand

  13. Engineering Applications of Artificial Intelligence 13 (2000) 611623 Genetic adaptive state estimation$

    E-print Network

    2000-01-01

    Engineering Applications of Artificial Intelligence 13 (2000) 611­623 Genetic adaptive state in a nonlinear jet engine. Our main conclusion is that the genetic adaptive state estimator has the potential Ltd. All rights reserved. Keywords: Estimation; Genetic algorithms; Jet engine surge=stall control 1

  14. Genetic engineering possibilities for CELSS: A bibliography and summary of techniques

    NASA Technical Reports Server (NTRS)

    Johnson, E. J.

    1982-01-01

    A bibliography of the most useful techniques employed in genetic engineering of higher plants, bacteria associated with plants, and plant cell cultures is provided. A resume of state-of-the-art genetic engineering of plants and bacteria is presented. The potential application of plant bacterial genetic engineering to CELSS (Controlled Ecological Life Support System) program and future research needs are discussed.

  15. Genetic Engineering of Algae for Enhanced Biofuel Production ?

    PubMed Central

    Radakovits, Randor; Jinkerson, Robert E.; Darzins, Al; Posewitz, Matthew C.

    2010-01-01

    There are currently intensive global research efforts aimed at increasing and modifying the accumulation of lipids, alcohols, hydrocarbons, polysaccharides, and other energy storage compounds in photosynthetic organisms, yeast, and bacteria through genetic engineering. Many improvements have been realized, including increased lipid and carbohydrate production, improved H2 yields, and the diversion of central metabolic intermediates into fungible biofuels. Photosynthetic microorganisms are attracting considerable interest within these efforts due to their relatively high photosynthetic conversion efficiencies, diverse metabolic capabilities, superior growth rates, and ability to store or secrete energy-rich hydrocarbons. Relative to cyanobacteria, eukaryotic microalgae possess several unique metabolic attributes of relevance to biofuel production, including the accumulation of significant quantities of triacylglycerol; the synthesis of storage starch (amylopectin and amylose), which is similar to that found in higher plants; and the ability to efficiently couple photosynthetic electron transport to H2 production. Although the application of genetic engineering to improve energy production phenotypes in eukaryotic microalgae is in its infancy, significant advances in the development of genetic manipulation tools have recently been achieved with microalgal model systems and are being used to manipulate central carbon metabolism in these organisms. It is likely that many of these advances can be extended to industrially relevant organisms. This review is focused on potential avenues of genetic engineering that may be undertaken in order to improve microalgae as a biofuel platform for the production of biohydrogen, starch-derived alcohols, diesel fuel surrogates, and/or alkanes. PMID:20139239

  16. Genetically engineered mouse models for studying inflammatory bowel disease.

    PubMed

    Mizoguchi, Atsushi; Takeuchi, Takahito; Himuro, Hidetomo; Okada, Toshiyuki; Mizoguchi, Emiko

    2016-01-01

    Inflammatory bowel disease (IBD) is a chronic intestinal inflammatory condition that is mediated by very complex mechanisms controlled by genetic, immune, and environmental factors. More than 74 kinds of genetically engineered mouse strains have been established since 1993 for studying IBD. Although mouse models cannot fully reflect human IBD, they have provided significant contributions for not only understanding the mechanism, but also developing new therapeutic means for IBD. Indeed, 20 kinds of genetically engineered mouse models carry the susceptibility genes identified in human IBD, and the functions of some other IBD susceptibility genes have also been dissected out using mouse models. Cutting-edge technologies such as cell-specific and inducible knockout systems, which were recently employed to mouse IBD models, have further enhanced the ability of investigators to provide important and unexpected rationales for developing new therapeutic strategies for IBD. In this review article, we briefly introduce 74 kinds of genetically engineered mouse models that spontaneously develop intestinal inflammation. Copyright © 2015 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. PMID:26387641

  17. Reactor engineering in large scale animal cell culture.

    PubMed

    Nienow, Alvin W

    2006-03-01

    This article mainly addresses the issues associated with the engineering of large-scale free suspension culture in agitated bioreactors >10,000 L because they have become the system of choice industrially. It is particularly concerned with problems that become increasingly important as the scale increases. However, very few papers have been written that are actually based on such large-scale studies and the few that do rarely address any of the issues quantitatively. Hence, it is necessary very often to extrapolate from small-scale work and this review tries to pull the two types of study together. It is shown that 'shear sensitivity' due to agitation and bursting bubbles is no longer considered a major problem. Homogeneity becomes increasingly important with respect to pH and nutrients at the largest scale and sub-surface feeding is recommended despite 'cleaning in place' concerns. There are still major questions with cell retention/recycle systems at these scales, either because of fouling, of capacity or of potential and different 'shear sensitivity' questions. Fed-batch operation gives rise to cell densities that have led to the use of oxygen and enriched air to meet oxygen demands. This strategy, in turn, gives rise to a CO(2) evolution rate that impacts on pH control, pCO(2) and osmolality. These interactions are difficult to resolve but if higher sparge and agitation intensities could be used to achieve the necessary oxygen transfer, the problem would largely disappear. Thus, the perception of 'shear sensitivity' is still impacting on the development of animal cell culture at the commercial scale. Microcarrier culture is also briefly addressed. Finally, some recommendations for bioreactor configuration and operating strategy are given. PMID:19003068

  18. Advances in genetic modification of farm animals using zinc-finger nucleases (ZFN).

    PubMed

    Petersen, Bjoern; Niemann, Heiner

    2015-02-01

    Genome editing tools (GET), including zinc-finger nucleases (ZFN), transcription activator-like endonucleases (TALENS), and meganucleases possess long recognition sites and are thus capable of cutting DNA in a very specific manner. These genome editing tools mediate targeted genetic alterations by enhancing DNA mutation frequency via induction of double-strand breaks at a predetermined genomic site. Compared to conventional homologous recombination based gene targeting, GETs can increase gene targeting and gene disruption via mutagenic DNA repair more than 10,000-fold. Recently, a novel class of genome editing tools was described that uses RNAs to target a specific genomic site. The CRISPR/Cas9 system is capable of targeting even multiple genomic sites in one shot and thus could be superior to ZFNs or TALEN. Current results indicate that these tools can be successfully employed in a broad range of organisms which renders them useful for improving the understanding of complex physiological systems, producing transgenic animals, including creating large animal models for human diseases, creating specific cell lines, and plants, and even for treating human genetic diseases. This review provides an update on the use of ZFNs to modify the genome of farm animals, summarizes current knowledge on the underlying mechanism, and discusses new opportunities for generating genetically modified farm animals. PMID:25596823

  19. Genetic Design Automation: engineering fantasy or scientific renewal?

    PubMed Central

    Lux, Matthew W.; Bramlett, Brian W.; Ball, David A.; Peccoud, Jean

    2013-01-01

    Synthetic biology aims to make genetic systems more amenable to engineering, which has naturally led to the development of Computer-Aided Design (CAD) tools. Experimentalists still primarily rely on project-specific ad-hoc workflows instead of domain-specific tools, suggesting that CAD tools are lagging behind the front line of the field. Here, we discuss the scientific hurdles that have limited the productivity gains anticipated from existing tools. We argue that the real value of efforts to develop CAD tools is the formalization of genetic design rules that determine the complex relationships between genotype and phenotype. PMID:22001068

  20. Animal Genetic Resource Trade Flows: The Utilization of Newly Imported Breeds and the Gene Flow of Imported Animals in the United States of America

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Animal germplasm exchange has recently received attention as a product of the FAO’s State of the World’s Animal Genetic Resources effort. Some have advocated a need to explore policies and regulations on the exchange of germplasm. However, there has been little comprehensive assessment of either th...

  1. Statistics of Scientific Procedures on Living Animals 2013: Experimentation continues to rise - the reliance on genetically-altered animals must be addressed.

    PubMed

    Hudson-Shore, Michelle

    2014-09-01

    The 2013 Statistics of Scientific Procedures on Living Animals reveal that the level of animal experimentation in Great Britain continues to rise, with 4.12 million procedures being conducted. The figures indicate that this is almost exclusively a result of the breeding and use of genetically-altered (GA) animals (i.e. genetically-modified animals, plus those with harmful genetic defects). The breeding of GA animals increased to over half (51%) of all the procedures, and GA animals were involved in 61% of all the procedures. Indeed, if these animals were removed from the statistics, the number of procedures would actually have declined by 4%. It is argued that the Coalition Government has failed to address this issue, and, as a consequence, will not be able to deliver its pledge to reduce animal use in science. Recent publications supporting the need to reassess the dominance of genetic alteration are also discussed, as well as the need to move away from the use of dogs as the default second species in safety testing. The general trends in the species used, and the numbers and types of procedures, are also reviewed. Finally, forthcoming changes to the statistics are discussed. PMID:25290946

  2. Assessing the Permeability of Landscape Features to Animal Movement: Using Genetic Structure to Infer Functional Connectivity

    PubMed Central

    Anderson, Sara J.; Kierepka, Elizabeth M.; Swihart, Robert K.; Latch, Emily K.; Rhodes, Olin E.

    2015-01-01

    Human-altered environments often challenge native species with a complex spatial distribution of resources. Hostile landscape features can inhibit animal movement (i.e., genetic exchange), while other landscape attributes facilitate gene flow. The genetic attributes of organisms inhabiting such complex environments can reveal the legacy of their movements through the landscape. Thus, by evaluating landscape attributes within the context of genetic connectivity of organisms within the landscape, we can elucidate how a species has coped with the enhanced complexity of human altered environments. In this research, we utilized genetic data from eastern chipmunks (Tamias striatus) in conjunction with spatially explicit habitat attribute data to evaluate the realized permeability of various landscape elements in a fragmented agricultural ecosystem. To accomplish this we 1) used logistic regression to evaluate whether land cover attributes were most often associated with the matrix between or habitat within genetically identified populations across the landscape, and 2) utilized spatially explicit habitat attribute data to predict genetically-derived Bayesian probabilities of population membership of individual chipmunks in an agricultural ecosystem. Consistency between the results of the two approaches with regard to facilitators and inhibitors of gene flow in the landscape indicate that this is a promising new way to utilize both landscape and genetic data to gain a deeper understanding of human-altered ecosystems. PMID:25719366

  3. Colonization genetics of an animal-dispersed plant (Vaccinium membranaceum) at Mount St Helens, Washington.

    PubMed

    Yang, S; Bishop, J G; Webster, M S

    2008-02-01

    Population founding and spatial spread may profoundly influence later population genetic structure, but their effects are difficult to quantify when population history is unknown. We examined the genetic effects of founder group formation in a recently founded population of the animal-dispersed Vaccinium membranaceum (black huckleberry) on new volcanic deposits at Mount St Helens (Washington, USA) 24 years post-eruption. Using amplified fragment length polymorphisms and assignment tests, we determined sources of the newly founded population and characterized genetic variation within new and source populations. Our analyses indicate that while founders were derived from many sources, about half originated from a small number of plants that survived the 1980 eruption in pockets of remnant soil embedded within primary successional areas. We found no evidence of a strong founder effect in the new population; indeed genetic diversity in the newly founded population tended to be higher than in some of the source regions. Similarly, formation of the new population did not increase among-population genetic variance, and there was no evidence of kin-structured dispersal in the new population. These results indicate that high gene flow among sources and long-distance dispersal were important processes shaping the genetic diversity in this young V. membranaceum population. Other species with similar dispersal abilities may also be able to colonize new habitats without significant reduction in genetic diversity or increase in differentiation among populations. PMID:18194163

  4. Genetic engineering of sulfur-degrading Sulfolobus

    SciTech Connect

    Ho, N.W.Y. . Lab. of Renewable Resources Engineering)

    1991-01-01

    Recent studies have shown that some microorganisms can play a significant role in removing the sulfur compound from coal. Sulfolobus acidocaldarius and related species are such microorganisms. The objective of this project is to develop a genetic transformation system for Sulfolobus species so that they could become the ideal host to overproduce homologous and heterologous enzymes that are most effective for the removal of sulfur from coal, particularly organic sulfur. Last quarter, we have identified three chemicals that can inhibit the growth of S. Acidocaldarius. These chemicals can be part of the selection system for the development of a transformation system for S. acidocaldarius. Due to the fact that Sulfolobus shibatae B12 becomes increasingly more attractive as a host for housing genes encoding desulfurization enzymes, in this period we also studied the affect of these three chemicals to growth of S. shibatae B12. We found that S. shibatae B12 is also sensitive to these chemicals. This quarter we succeeded in the isolation and purification of the double-stranded DNA virus from S. shibatae B12. Furthermore, the individual EcoRI and BamH1 fragments of the virus have also been cloned into pUC19 plasmid. These plasmids will be used for the construction of the final E. coli-Sulfolobus shuttle vector. 5 Flurouracil (5FU) is one of the chemicals that inhibit growth of Sulfolobus. Resistance strain of S. acidocaldarius to 5FU has also been isolated. DNA from the 5FU resistance strain has also been isolated. 2 figs.

  5. Genetically engineered luminescent proteins in biosensing

    NASA Astrophysics Data System (ADS)

    Rowe, Laura; Ensor, Mark; Scott, Daniel; Deo, Sapna; Daunert, Sylvia

    2006-02-01

    Luminescent proteins originally isolated from marine or terrestrial organisms have played a key role in the development of several biosensing systems. These proteins have been used in a variety of applications including, immunoassays, binding assays, cell-based sensing, high throughput screening, optical imaging, etc. Among the luminescent proteins isolated, the bioluminescent protein aequorin has been one of the proteins at the forefront in terms of its use in a vast number of biosensing systems. In our laboratory, we have employed aequorin as a label in the development of highly sensitive assays through chemical and genetic modifications from single step analysis of physiologically important molecules in biological fluids. An important aspect of optimizing these assays for clinical use involves understanding the stability of the various aequorin variants that are available. To this end we have designed several stability studies involving three important aequorin mutants, Mutant S, Mutant 5, and Mutant 53. The cysteine free aequorin, Mutant S, has been the most ubiquitously used aequorin variant in our laboratory because of its increased stability and activity as compared to native aequorin. Mutant 5 and Mutant 53 contain a single cyteine residue at position 5 and 53 in the protein, respectively. Because of the presence of a single cysteine residue, Mutant 5 and Mutant 53 both can be site-specifically conjugated. This site specific conjugation capability gives Mutant 5 and Mutant 53 an advantage over native aequorin when developing assays. Additional studies optimizing the expression, purification, and charging of aequorin Mutant S were also performed. A thorough understanding of the efficient expression, purification, and storage of these aequorin mutants will allow for the more practical utilization of these mutants in the development of future biosensing systems.

  6. Targeted drug delivery using genetically engineered diatom biosilica.

    PubMed

    Delalat, Bahman; Sheppard, Vonda C; Rasi Ghaemi, Soraya; Rao, Shasha; Prestidge, Clive A; McPhee, Gordon; Rogers, Mary-Louise; Donoghue, Jacqueline F; Pillay, Vinochani; Johns, Terrance G; Kröger, Nils; Voelcker, Nicolas H

    2015-01-01

    The ability to selectively kill cancerous cell populations while leaving healthy cells unaffected is a key goal in anticancer therapeutics. The use of nanoporous silica-based materials as drug-delivery vehicles has recently proven successful, yet production of these materials requires costly and toxic chemicals. Here we use diatom microalgae-derived nanoporous biosilica to deliver chemotherapeutic drugs to cancer cells. The diatom Thalassiosira pseudonana is genetically engineered to display an IgG-binding domain of protein G on the biosilica surface, enabling attachment of cell-targeting antibodies. Neuroblastoma and B-lymphoma cells are selectively targeted and killed by biosilica displaying specific antibodies sorbed with drug-loaded nanoparticles. Treatment with the same biosilica leads to tumour growth regression in a subcutaneous mouse xenograft model of neuroblastoma. These data indicate that genetically engineered biosilica frustules may be used as versatile 'backpacks' for the targeted delivery of poorly water-soluble anticancer drugs to tumour sites. PMID:26556723

  7. Genetic analysis of Down syndrome facilitated by mouse chromosome engineering

    PubMed Central

    Zhang, Li; Fu, Dawei; Belichenko, Pavel V.; Liu, Chunhong; Kleschevnikov, Alexander M.; Pao, Annie; Liang, Ping; Clapcote, Steven J.; Mobley, William C.; Yu, Y. Eugene

    2012-01-01

    Human trisomy 21 is the most frequent live-born human aneuploidy and causes a constellation of disease phenotypes classified as Down syndrome, which include heart defects, myeloproliferative disorder, cognitive disabilities and Alzheimer-type neurodegeneration. Because these phenotypes are associated with an extra copy of a human chromosome, the genetic analysis of Down syndrome has been a major challenge. To complement human genetic approaches, mouse models have been generated and analyzed based on evolutionary conservation between the human and mouse genomes. These efforts have been greatly facilitated by Cre/loxP-mediated mouse chromosome engineering, which may result in the establishment of minimal critical genomic regions and eventually new dosage-sensitive genes associated with Down syndrome phenotypes. The success in genetic analysis of Down syndrome will further enhance our understanding of this disorder and lead to better strategies in developing effective therapeutic interventions. PMID:22126738

  8. Eradication of malaria through genetic engineering: the current situation.

    PubMed

    Chong, Wing-Chui; Basir, Rusliza; Fei, Yam Mun

    2013-02-01

    Malaria is an intra-cellular parasitic protozoon responsible for millions of deaths annually. Host and parasite genetic factors are crucial in affecting susceptibility to malaria and progression of the disease. Recent increased deployment of vector controls and new artemisinin combination therapies have dramatically reduced the mortality and morbidity of malaria worldwide. However, the gradual emergence of parasite and mosquito resistance has raised alarm regarding the effectiveness of current artemisinin-based therapies. In this review, mechanisms of anti-malarial drug resistance in the Plasmodium parasite and new genetically engineered tools of research priorities are discussed. The complexity of the parasite lifecycle demands novel interventions to achieve global eradication. However, turning laboratory discovered transgenic interventions into functional products entails multiple experimental phases in addition to ethical and safety hurdles. Uncertainty over the regulatory status and public acceptance further discourage the implementation of genetically modified organisms. PMID:23339908

  9. A review on SNP and other types of molecular markers and their use in animal genetics

    PubMed Central

    Vignal, Alain; Milan, Denis; SanCristobal, Magali; Eggen, André

    2002-01-01

    During the last ten years, the use of molecular markers, revealing polymorphism at the DNA level, has been playing an increasing part in animal genetics studies. Amongst others, the microsatellite DNA marker has been the most widely used, due to its easy use by simple PCR, followed by a denaturing gel electrophoresis for allele size determination, and to the high degree of information provided by its large number of alleles per locus. Despite this, a new marker type, named SNP, for Single Nucleotide Polymorphism, is now on the scene and has gained high popularity, even though it is only a bi-allelic type of marker. In this review, we will discuss the reasons for this apparent step backwards, and the pertinence of the use of SNPs in animal genetics, in comparison with other marker types. PMID:12081799

  10. The use of genetic engineering techniques to improve the lipid composition in meat, milk and fish products: a review.

    PubMed

    ?wi?tkiewicz, S; ?wi?tkiewicz, M; Arczewska-W?osek, A; Józefiak, D

    2015-04-01

    The health-promoting properties of dietary long-chain n-3 polyunsaturated fatty acids (n-3 LCPUFAs) for humans are well-known. Products of animal-origin enriched with n-3 LCPUFAs can be a good example of functional food, that is food that besides traditionally understood nutritional value may have a beneficial influence on the metabolism and health of consumers, thus reducing the risk of various lifestyle diseases such as atherosclerosis and coronary artery disease. The traditional method of enriching meat, milk or eggs with n-3 LCPUFA is the manipulation of the composition of animal diets. Huge progress in the development of genetic engineering techniques, for example transgenesis, has enabled the generation of many kinds of genetically modified animals. In recent years, one of the aims of animal transgenesis has been the modification of the lipid composition of meat and milk in order to improve the dietetic value of animal-origin products. This article reviews and discusses the data in the literature concerning studies where techniques of genetic engineering were used to create animal-origin products modified to contain health-promoting lipids. These studies are still at the laboratory stage, but their results have demonstrated that the transgenesis of pigs, cows, goats and fishes can be used in the future as efficient methods of production of healthy animal-origin food of high dietetic value. However, due to high costs and a low level of public acceptance, the introduction of this technology to commercial animal production and markets seems to be a distant prospect. PMID:25500170

  11. Chromosome Y genetic variants: impact in animal models and on human disease.

    PubMed

    Prokop, J W; Deschepper, C F

    2015-11-01

    Chromosome Y (chrY) variation has been associated with many complex diseases ranging from cancer to cardiovascular disorders. Functional roles of chrY genes outside of testes are suggested by the fact that they are broadly expressed in many other tissues and correspond to regulators of basic cellular functions (such as transcription, translation, and protein stability). However, the unique genetic properties of chrY (including the lack of meiotic crossover and the presence of numerous highly repetitive sequences) have made the identification of causal variants very difficult. Despite the prior lack of reliable sequences and/or data on genetic polymorphisms, earlier studies with animal chrY consomic strains have made it possible to narrow down the phenotypic contributions of chrY. Some of the evidence so far indicates that chrY gene variants associate with regulatory changes in the expression of other autosomal genes, in part via epigenetic effects. In humans, a limited number of studies have shown associations between chrY haplotypes and disease traits. However, recent sequencing efforts have made it possible to greatly increase the identification of genetic variants on chrY, which promises that future association of chrY with disease traits will be further refined. Continuing studies (both in humans and in animal models) will be critical to help explain the many sex-biased disease states in human that are contributed to not only by the classical sex steroid hormones, but also by chrY genetics. PMID:26286457

  12. Versatile RNA-sensing transcriptional regulators for engineering genetic networks

    PubMed Central

    Lucks, Julius B.; Qi, Lei; Mutalik, Vivek K.; Wang, Denise; Arkin, Adam P.

    2011-01-01

    The widespread natural ability of RNA to sense small molecules and regulate genes has become an important tool for synthetic biology in applications as diverse as environmental sensing and metabolic engineering. Previous work in RNA synthetic biology has engineered RNA mechanisms that independently regulate multiple targets and integrate regulatory signals. However, intracellular regulatory networks built with these systems have required proteins to propagate regulatory signals. In this work, we remove this requirement and expand the RNA synthetic biology toolkit by engineering three unique features of the plasmid pT181 antisense-RNA-mediated transcription attenuation mechanism. First, because the antisense RNA mechanism relies on RNA-RNA interactions, we show how the specificity of the natural system can be engineered to create variants that independently regulate multiple targets in the same cell. Second, because the pT181 mechanism controls transcription, we show how independently acting variants can be configured in tandem to integrate regulatory signals and perform genetic logic. Finally, because both the input and output of the attenuator is RNA, we show how these variants can be configured to directly propagate RNA regulatory signals by constructing an RNA-meditated transcriptional cascade. The combination of these three features within a single RNA-based regulatory mechanism has the potential to simplify the design and construction of genetic networks by directly propagating signals as RNA molecules. PMID:21555549

  13. Genetic engineering of the chloroplast: novel tools and new applications.

    PubMed

    Bock, Ralph

    2014-04-01

    The plastid genome represents an attractive target of genetic engineering in crop plants. Plastid transgenes often give high expression levels, can be stacked in operons and are largely excluded from pollen transmission. Recent research has greatly expanded our toolbox for plastid genome engineering and many new proof-of-principle applications have highlighted the enormous potential of the transplastomic technology in both crop improvement and the development of plants as bioreactors for the sustainable and cost-effective production of biopharmaceuticals, enzymes and raw materials for the chemical industry. This review describes recent technological advances with plastid transformation in seed plants. It focuses on novel tools for plastid genome engineering and transgene expression and summarizes progress with harnessing the potential of plastid transformation in biotechnology. PMID:24679252

  14. Utilization of farm animal genetic resources in a changing agro-ecological environment in the Nordic countries

    PubMed Central

    Kantanen, Juha; Løvendahl, Peter; Strandberg, Erling; Eythorsdottir, Emma; Li, Meng-Hua; Kettunen-Præbel, Anne; Berg, Peer; Meuwissen, Theo

    2015-01-01

    Livestock production is the most important component of northern European agriculture and contributes to and will be affected by climate change. Nevertheless, the role of farm animal genetic resources in the adaptation to new agro-ecological conditions and mitigation of animal production’s effects on climate change has been inadequately discussed despite there being several important associations between animal genetic resources and climate change issues. The sustainability of animal production systems and future food security require access to a wide diversity of animal genetic resources. There are several genetic questions that should be considered in strategies promoting adaptation to climate change and mitigation of environmental effects of livestock production. For example, it may become important to choose among breeds and even among farm animal species according to their suitability to a future with altered production systems. Some animals with useful phenotypes and genotypes may be more useful than others in the changing environment. Robust animal breeds with the potential to adapt to new agro-ecological conditions and tolerate new diseases will be needed. The key issue in mitigation of harmful greenhouse gas effects induced by livestock production is the reduction of methane (CH4) emissions from ruminants. There are differences in CH4 emissions among breeds and among individual animals within breeds that suggest a potential for improvement in the trait through genetic selection. Characterization of breeds and individuals with modern genomic tools should be applied to identify breeds that have genetically adapted to marginal conditions and to get critical information for breeding and conservation programs for farm animal genetic resources. We conclude that phenotyping and genomic technologies and adoption of new breeding approaches, such as genomic selection introgression, will promote breeding for useful characters in livestock species. PMID:25767477

  15. Utilization of farm animal genetic resources in a changing agro-ecological environment in the Nordic countries.

    PubMed

    Kantanen, Juha; Løvendahl, Peter; Strandberg, Erling; Eythorsdottir, Emma; Li, Meng-Hua; Kettunen-Præbel, Anne; Berg, Peer; Meuwissen, Theo

    2015-01-01

    Livestock production is the most important component of northern European agriculture and contributes to and will be affected by climate change. Nevertheless, the role of farm animal genetic resources in the adaptation to new agro-ecological conditions and mitigation of animal production's effects on climate change has been inadequately discussed despite there being several important associations between animal genetic resources and climate change issues. The sustainability of animal production systems and future food security require access to a wide diversity of animal genetic resources. There are several genetic questions that should be considered in strategies promoting adaptation to climate change and mitigation of environmental effects of livestock production. For example, it may become important to choose among breeds and even among farm animal species according to their suitability to a future with altered production systems. Some animals with useful phenotypes and genotypes may be more useful than others in the changing environment. Robust animal breeds with the potential to adapt to new agro-ecological conditions and tolerate new diseases will be needed. The key issue in mitigation of harmful greenhouse gas effects induced by livestock production is the reduction of methane (CH4) emissions from ruminants. There are differences in CH4 emissions among breeds and among individual animals within breeds that suggest a potential for improvement in the trait through genetic selection. Characterization of breeds and individuals with modern genomic tools should be applied to identify breeds that have genetically adapted to marginal conditions and to get critical information for breeding and conservation programs for farm animal genetic resources. We conclude that phenotyping and genomic technologies and adoption of new breeding approaches, such as genomic selection introgression, will promote breeding for useful characters in livestock species. PMID:25767477

  16. Fall 1999 Biology 111 Final Exam Cancer, HIV, Genetic Engineering and Pseudo-Cumulative.

    E-print Network

    Campbell, A. Malcolm

    1 Fall 1999 Biology 111 Final Exam Cancer, HIV, Genetic Engineering and Pseudo occurring mechanism to produce two genetically identical cells. b) Although these two cells are genetically and protooncogenes. This work set the stage for our understanding of the human genetics behind cancer. What

  17. DOI: 10.1002/adma.200602262 Weaving Genetically Engineered Functionality into Mechanically

    E-print Network

    Van Vliet, Krystyn J.

    DOI: 10.1002/adma.200602262 Weaving Genetically Engineered Functionality into Mechanically Robust using M13 filamentous viruses (or bacter- iophages). This work applies genetic engineering, chemical, the production of functionalized fibers has posed a challenge in materials science and engineering. Here we

  18. REVERSE ENGINEERING BY MEANS OF GENETIC PROGRAMMING OF METABOLIC PATHWAYS FROM OBSERVED DATA

    E-print Network

    Fernandez, Thomas

    REVERSE ENGINEERING BY MEANS OF GENETIC PROGRAMMING OF METABOLIC PATHWAYS FROM OBSERVED DATA John R, to automatically reverse engineer the network from the data. Genetic programming (Koza, Bennett, Andre, and Keane. Koza Biomedical Informatics, Department of Medicine Department of Electrical Engineering Stanford

  19. Specific immunotherapy by genetically engineered APCs: the "guided missile" strategy.

    PubMed

    Wu, B; Wu, J M; Miagkov, A; Adams, R N; Levitsky, H I; Drachman, D B

    2001-04-01

    We tested the hypothesis that APCs genetically engineered to present an Ag and to express Fas ligand (FasL) simultaneously can target and eliminate Ag-specific T cells. Transgenic T cells specific for influenza hemagglutinin (HA) were used as targets. We prepared recombinant vaccinia virus vectors (VVV) to transfer the gene constructs individually or simultaneously into APCs. We prevented unwanted viral replication by attenuating the VVVs with psoralen-UV light treatment. For presentation of the HA Ag, APCs were transduced with cDNA for HA flanked by sequences of the lysosome-associated membrane protein that direct efficient processing and presentation of the Ag by APCs. As a "warhead" for the APCs, we transduced them with the gene for FasL, which induces apoptosis of Fas-expressing activated T cells. To protect the transduced APCs from self-destruction by FasL, we transferred cDNA for a truncated form of Fas-associated death domain, which inhibits Fas-mediated cell death. Our results show that the engineered APCs effectively expressed the genes of interest. APCs transduced with VVV carrying all three gene constructs specifically killed HA-transgenic T cells in culture. Coculture with T cells specific for an unrelated Ag (OVA) had no significant effect. Our in vitro findings show that APCs can be genetically engineered to target and kill Ag-specific T cells and represent a promising novel strategy for the specific treatment of autoimmune diseases. PMID:11254740

  20. Universal genetic assay for engineering extracellular protein expression.

    PubMed

    Haitjema, Charles H; Boock, Jason T; Natarajan, Aravind; Dominguez, Miguel A; Gardner, Jeffrey G; Keating, David H; Withers, Sydnor T; DeLisa, Matthew P

    2014-02-21

    A variety of strategies now exist for the extracellular expression of recombinant proteins using laboratory strains of Escherichia coli . However, secreted proteins often accumulate in the culture medium at levels that are too low to be practically useful for most synthetic biology and metabolic engineering applications. The situation is compounded by the lack of generalized screening tools for optimizing the secretion process. To address this challenge, we developed a genetic approach for studying and engineering protein-secretion pathways in E. coli . Using the YebF pathway as a model, we demonstrate that direct fluorescent labeling of tetracysteine-motif-tagged secretory proteins with the biarsenical compound FlAsH is possible in situ without the need to recover the cell-free supernatant. High-throughput screening of a bacterial strain library yielded superior YebF expression hosts capable of secreting higher titers of YebF and YebF-fusion proteins into the culture medium. We also show that the method can be easily extended to other secretory pathways, including type II and type III secretion, directly in E. coli . Thus, our FlAsH-tetracysteine-based genetic assay provides a convenient, high-throughput tool that can be applied generally to diverse secretory pathways. This platform should help to shed light on poorly understood aspects of these processes as well as to further assist in the construction of engineered E. coli strains for efficient secretory-protein production. PMID:24200127

  1. Genetic Engineering of Mesenchymal Stem Cells for Regenerative Medicine.

    PubMed

    Nowakowski, Adam; Walczak, Piotr; Janowski, Miroslaw; Lukomska, Barbara

    2015-10-01

    Mesenchymal stem cells (MSCs), which can be obtained from various organs and easily propagated in vitro, are one of the most extensively used types of stem cells and have been shown to be efficacious in a broad set of diseases. The unique and highly desirable properties of MSCs include high migratory capacities toward injured areas, immunomodulatory features, and the natural ability to differentiate into connective tissue phenotypes. These phenotypes include bone and cartilage, and these properties predispose MSCs to be therapeutically useful. In addition, MSCs elicit their therapeutic effects by paracrine actions, in which the metabolism of target tissues is modulated. Genetic engineering methods can greatly amplify these properties and broaden the therapeutic capabilities of MSCs, including transdifferentiation toward diverse cell lineages. However, cell engineering can also affect safety and increase the cost of therapy based on MSCs; thus, the advantages and disadvantages of these procedures should be discussed. In this review, the latest applications of genetic engineering methods for MSCs with regenerative medicine purposes are presented. PMID:26140302

  2. The delicate balance in genetically engineering live vaccines

    PubMed Central

    Galen, James E.; Curtiss, Roy

    2014-01-01

    Contemporary vaccine development relies less on empirical methods of vaccine construction, and now employs a powerful array of precise engineering strategies to construct immunogenic live vaccines. In this review, we will survey various engineering techniques used to create attenuated vaccines, with an emphasis on recent advances and insights. We will further explore the adaptation of attenuated strains to create multivalent vaccine platforms for immunization against multiple unrelated pathogens. These carrier vaccines are engineered to deliver sufficient levels of protective antigens to appropriate lymphoid inductive sites to elicit both carrier-specific and foreign antigen-specific immunity. Although many of these technologies were originally developed for use in Salmonella vaccines, application of the essential logic of these approaches will be extended to development of other enteric vaccines where possible. A central theme driving our discussion will stress that the ultimate success of an engineered vaccine rests on achieving the proper balance between attenuation and immunogenicity. Achieving this balance will avoid over-activation of inflammatory responses, which results in unacceptable reactogenicity, but will retain sufficient metabolic fitness to enable the live vaccine to reach deep tissue inductive sites and trigger protective immunity. The breadth of examples presented herein will clearly demonstrate that genetic engineering offers the potential for rapidly propelling vaccine development forward into novel applications and therapies which will significantly expand the role of vaccines in public health. PMID:24370705

  3. The Plant Genetic Engineering Laboratory For Desert Adaptation

    NASA Astrophysics Data System (ADS)

    Kemp, John D.; Phillips, Gregory C.

    1985-11-01

    The Plant Genetic Engineering Laboratory for Desert Adaptation (PGEL) is one of five Centers of Technical Excellence established as a part of the state of New Mexico's Rio Grande Research Corridor (RGRC). The scientific mission of PGEL is to bring innovative advances in plant biotechnology to bear on agricultural productivity in arid and semi-arid regions. Research activities focus on molecular and cellular genetics technology development in model systems, but also include stress physiology investigations and development of desert plant resources. PGEL interacts with the Los Alamos National Laboratory (LANL), a national laboratory participating in the RGRC. PGEL also has an economic development mission, which is being pursued through technology transfer activities to private companies and public agencies.

  4. NATURAL GENETIC ENGINEERING AND NATURAL GENOME EDITING Epigenetic Regulation of Mammalian

    E-print Network

    Jordan, King

    NATURAL GENETIC ENGINEERING AND NATURAL GENOME EDITING Epigenetic Regulation of Mammalian Genomes to the epigenetic mechanisms that regulate mammalian genomes, emphasizing nucleosome positioning and epigenetic histone modifications. A link between TEs and epigenetics rests on the fact that underlying genetic

  5. Genetic-evolution-based optimization methods for engineering design

    NASA Technical Reports Server (NTRS)

    Rao, S. S.; Pan, T. S.; Dhingra, A. K.; Venkayya, V. B.; Kumar, V.

    1990-01-01

    This paper presents the applicability of a biological model, based on genetic evolution, for engineering design optimization. Algorithms embodying the ideas of reproduction, crossover, and mutation are developed and applied to solve different types of structural optimization problems. Both continuous and discrete variable optimization problems are solved. A two-bay truss for maximum fundamental frequency is considered to demonstrate the continuous variable case. The selection of locations of actuators in an actively controlled structure, for minimum energy dissipation, is considered to illustrate the discrete variable case.

  6. Genetically engineered acidophilic heterotrophic bacteria by bacteriophage transduction

    SciTech Connect

    Ward, T.E.; Bruhn, D.F.; Bulmer, D.F.

    1989-05-10

    A bacteriophage capable of infecting acidophilic heterotrophic bacteria and processes for genetically engineering acidophilic bacteria for biomining or sulfur removal from coal are disclosed. The bacteriophage is capable of growth in cells existing at pH at or below 3.0. Lytic forms of the phage introduced into areas experiencing acid drainage kill the bacteria causing such drainage. Lysogenic forms of the phage having genes for selective removal of metallic or nonmetallic elements can be introduced into acidophilic bacteria to effect removal of the desired element from ore or coal. 1 fig., 1 tab.

  7. Cancer Regression in Patients After Transfer of Genetically Engineered Lymphocytes

    NASA Astrophysics Data System (ADS)

    Morgan, Richard A.; Dudley, Mark E.; Wunderlich, John R.; Hughes, Marybeth S.; Yang, James C.; Sherry, Richard M.; Royal, Richard E.; Topalian, Suzanne L.; Kammula, Udai S.; Restifo, Nicholas P.; Zheng, Zhili; Nahvi, Azam; de Vries, Christiaan R.; Rogers-Freezer, Linda J.; Mavroukakis, Sharon A.; Rosenberg, Steven A.

    2006-10-01

    Through the adoptive transfer of lymphocytes after host immunodepletion, it is possible to mediate objective cancer regression in human patients with metastatic melanoma. However, the generation of tumor-specific T cells in this mode of immunotherapy is often limiting. Here we report the ability to specifically confer tumor recognition by autologous lymphocytes from peripheral blood by using a retrovirus that encodes a T cell receptor. Adoptive transfer of these transduced cells in 15 patients resulted in durable engraftment at levels exceeding 10% of peripheral blood lymphocytes for at least 2 months after the infusion. We observed high sustained levels of circulating, engineered cells at 1 year after infusion in two patients who both demonstrated objective regression of metastatic melanoma lesions. This study suggests the therapeutic potential of genetically engineered cells for the biologic therapy of cancer.

  8. Applications of Population Genetics to Animal Breeding, from Wright, Fisher and Lush to Genomic Prediction

    PubMed Central

    Hill, William G.

    2014-01-01

    Although animal breeding was practiced long before the science of genetics and the relevant disciplines of population and quantitative genetics were known, breeding programs have mainly relied on simply selecting and mating the best individuals on their own or relatives’ performance. This is based on sound quantitative genetic principles, developed and expounded by Lush, who attributed much of his understanding to Wright, and formalized in Fisher’s infinitesimal model. Analysis at the level of individual loci and gene frequency distributions has had relatively little impact. Now with access to genomic data, a revolution in which molecular information is being used to enhance response with “genomic selection” is occurring. The predictions of breeding value still utilize multiple loci throughout the genome and, indeed, are largely compatible with additive and specifically infinitesimal model assumptions. I discuss some of the history and genetic issues as applied to the science of livestock improvement, which has had and continues to have major spin-offs into ideas and applications in other areas. PMID:24395822

  9. Genetic Variability of MicroRNA Genes in 15 Animal Species.

    PubMed

    Zorc, Minja; Obsteter, Jana; Dovc, Peter; Kunej, Tanja

    2015-01-01

    MicroRNAs (miRNA) are a class of non-coding RNAs important in posttranscriptional regulation of target genes. Previous studies have proven that genetic variability of miRNA genes (miR-SNP) has an impact on phenotypic variation and disease susceptibility in human, mice and some livestock species. MicroRNA gene polymorphisms could therefore represent biomarkers for phenotypic traits also in other animal species. We upgraded our previously developed tool miRNA SNiPer to the version 4.0 which enables the search of miRNA genetic variability in 15 animal genomes: http://www.integratomics-time.com/miRNA-SNiPer. Genome-wide in silico screening (GWISS) of 15 genomes revealed that based on the current database releases, miRNA genes are most polymorphic in cattle, followed by human, fruitfly, mouse, chicken, pig, horse, and sheep. The difference in the number of miRNA gene polymorphisms between species is most probably not due to a biological reason and lack of genetic variability in some species, but to different stage of sequencing projects and differences in development of genomic resource databases in different species. Genome screening revealed several interesting genomic hotspots. For instance, several multiple nucleotide polymorphisms (MNPs) are present within mature seed region in cattle. Among miR-SNPs 46 are present on commercial whole-genome SNP chips: 16 in cattle, 26 in chicken, two in sheep and two in pig. The update of the miRNA SNiPer tool and the generated catalogs will serve researchers as a starting point in designing projects dealing with the effects of genetic variability of miRNA genes. PMID:25874014

  10. Genetic Variability of MicroRNA Genes in 15 Animal Species

    PubMed Central

    Zorc, Minja; Obsteter, Jana; Dovc, Peter; Kunej, Tanja

    2015-01-01

    MicroRNAs (miRNA) are a class of non-coding RNAs important in posttranscriptional regulation of target genes. Previous studies have proven that genetic variability of miRNA genes (miR-SNP) has an impact on phenotypic variation and disease susceptibility in human, mice and some livestock species. MicroRNA gene polymorphisms could therefore represent biomarkers for phenotypic traits also in other animal species. We upgraded our previously developed tool miRNA SNiPer to the version 4.0 which enables the search of miRNA genetic variability in 15 animal genomes: http://www.integratomics-time.com/miRNA-SNiPer. Genome-wide in silico screening (GWISS) of 15 genomes revealed that based on the current database releases, miRNA genes are most polymorphic in cattle, followed by human, fruitfly, mouse, chicken, pig, horse, and sheep. The difference in the number of miRNA gene polymorphisms between species is most probably not due to a biological reason and lack of genetic variability in some species, but to different stage of sequencing projects and differences in development of genomic resource databases in different species. Genome screening revealed several interesting genomic hotspots. For instance, several multiple nucleotide polymorphisms (MNPs) are present within mature seed region in cattle. Among miR-SNPs 46 are present on commercial whole-genome SNP chips: 16 in cattle, 26 in chicken, two in sheep and two in pig. The update of the miRNA SNiPer tool and the generated catalogs will serve researchers as a starting point in designing projects dealing with the effects of genetic variability of miRNA genes. PMID:25874014

  11. Overcoming challenges in engineering the genetic code M.J. Lajoie, D. Soll, G.M. Church

    E-print Network

    Church, George M.

    ÔØ Å ÒÙ× Ö ÔØ Overcoming challenges in engineering the genetic code M.J. Lajoie, D. S¨oll, G in engineering the genetic code, Journal of Molecular Biology (2015), doi: 10.1016/j.jmb.2015 challenges in engineering the genetic code Lajoie MJ1,2, , Söll D3 , Church GM1,4 1. Department of Genetics

  12. Measuring genetic stability in bacteria of potential use in genetic engineering

    SciTech Connect

    Walter, M.V.; Porteous, A.; Seidler, R.J.

    1987-01-01

    Four commonly used conjugation techniques, colony cross streak (CCS), broth mating (BM), combined spread plate (CSP), and membrane filtration (MF), were compared with each other regarding reliability, sensitivity, and complexity in evaluating the transfer of conjugative plasmids. Five plasmids representing several incompatibility groups plus a variety of laboratory and environmental isolates were used as mating pairs. The suitability of each method was evaluated for use in a routine assessment of the genetic stability of genetically engineered microorganisms. By the CSP and MF techniques with laboratory strains such as Escherichia coli and Pseudomonas species as recipients, transconjugants were usually produced in 100% of the mating trials. However, when environmental strains isolated from plants and soil were used as recipients, transconjugants were detected in 100% of some crosses and in as little as 30% in other crosses depending on the plasmid and recipient used. In general, differences in the percentage of successful matings between the CSP and MF techniques compared with the BM and CCS techniques were not statistically significant. Occasionally, certain mating pairs consistently produced transconjugants by CCS or BM but not by CSP or MF. Since any single conjugation mating technique is not completely reliable in detecting transconjugants, a combined mating technique has been developed which integrate the CCS, CSP, BM, and MF methods as a single procedure to assess the mobility of plasmid DNA of genetically engineered microorganisms.

  13. Measuring genetic stability in bacteria of potential use in genetic engineering.

    PubMed

    Walter, M V; Porteous, A; Seidler, R J

    1987-01-01

    Four commonly used conjugation techniques, colony cross streak (CCS), broth mating (BM), combined spread plate (CSP), and membrane filtration (MF), were compared with each other regarding reliability, sensitivity, and complexity in evaluating the transfer of conjugative plasmids. Five plasmids representing several incompatibility groups plus a variety of laboratory and environmental isolates were used as mating pairs. The suitability of each method was evaluated for use in a routine assessment of the genetic stability of genetically engineered microorganisms. By the CSP and MF techniques with laboratory strains such as Escherichia coli and Pseudomonas species as recipients, transconjugants were usually produced in 100% of the mating trials. However, when environmental strains isolated from plants and soil were used as recipients, transconjugants were detected in 100% of some crosses and in as little as 30% in other crosses depending on the plasmid and recipient used. In general, differences in the percentage of successful matings between the CSP and MF techniques compared with the BM and CCS techniques were not statistically significant at the P less than or equal to 0.05 level. Occasionally, certain mating pairs consistently produced transconjugants by CCS or BM but not by CSP or MF. Since any single conjugation mating technique is not completely reliable in detecting transconjugants, we have developed a combined mating technique which integrates the CCS, CSP, BM, and MF methods as a single procedure to assess the mobility of plasmid DNA of genetically engineered microorganisms. PMID:3548588

  14. Genetic engineering and chemical conjugation of potato virus X.

    PubMed

    Lee, Karin L; Uhde-Holzem, Kerstin; Fischer, Rainer; Commandeur, Ulrich; Steinmetz, Nicole F

    2014-01-01

    Here we report the genetic engineering and chemical modification of potato virus X (PVX) for the presentation of various peptides, proteins, and fluorescent dyes, or other chemical modifiers. Three different ways of genetic engineering are described and by these means, peptides are successfully expressed not only when the foot and mouth disease virus (FMDV) 2A sequence or a flexible glycine-serine linker is included, but also when the peptide is fused directly to the PVX coat protein. When larger proteins or unfavorable peptide sequences are presented, a partial fusion via the FMDV 2A sequence is preferable. When these PVX chimeras retain the ability to assemble into viral particles and are thus able to infect plants systemically, they can be utilized to inoculate susceptible plants for isolation of sufficient amounts of virus particles for subsequent chemical modification. Chemical modification is required for the display of nonbiological ligands such as fluorophores, polymers, and small drug compounds. We present three methods of chemical bioconjugation. For direct conjugation of small chemical modifiers to solvent exposed lysines, N-hydroxysuccinimide chemistry can be applied. Bio-orthogonal reactions such as copper-catalyzed azide-alkyne cycloaddition or hydrazone ligation are alternatives to achieve more efficient conjugation (e.g., when working with high molecular weight or insoluble ligands). Furthermore, hydrazone ligation offers an attractive route for the introduction of pH-cleavable cargos (e.g., therapeutic molecules). PMID:24243237

  15. Prospects of genetic engineering for robust insect resistance.

    PubMed

    Birkett, Michael A; Pickett, John A

    2014-06-01

    Secondary plant metabolites are potentially of great value for providing robust resistance in plants against insect pests. Such metabolites often comprise small lipophilic molecules (SLMs), and can be similar also in terms of activity to currently used insecticides, for example, the pyrethroids, neonicotinoids and butenolides, which provide more effective pest management than the resistance traits exploited by breeding. Crop plants mostly lack the SLMs that provide their wild ancestors with resistance to pests. However, resistance traits based on the biosynthesis of SLMs present promising new opportunities for crop resistance to pests. Advances in genetic engineering of secondary metabolite pathways that produce insecticidal compounds and, more recently, SLMs involved in plant colonisation and development, for example, insect pheromones, offer specific new approaches but which are more demanding than the genetic engineering approaches adopted so far. In addition, nature also offers various opportunities for exploiting induction or priming for resistance metabolite generation. Thus, use of non-constitutively expressed resistance traits delivered via the seed is a more sustainable approach than previously achieved, and could underpin development of perennial arable crops protected by sentinel plant technologies. PMID:24747775

  16. Neurodevelopmental Malformations of the Cerebellar Vermis in Genetically Engineered Rats.

    PubMed

    Ramos, Raddy L; Van Dine, Sarah E; Gilbert, Mary E; Leheste, Joerg R; Torres, German

    2015-12-01

    The cerebellar vermis is particularly vulnerable to neurodevelopmental malformations in humans and rodents. Sprague-Dawley, and Long-Evans rats exhibit spontaneous cerebellar malformations consisting of heterotopic neurons and glia in the molecular layer of the vermis. Malformations are almost exclusively found along the primary fissure and are indicative of deficits of neuronal migration during cerebellar development. In the present report, we test the prediction that genetically engineered rats on Sprague-Dawley or Long-Evans backgrounds will also exhibit the same cerebellar malformations. Consistent with our hypothesis, we found that three different transgenic lines on two different backgrounds had cerebellar malformations. Heterotopia in transgenic rats had identical cytoarchitecture as that observed in wild-type rats including altered morphology of Bergmann glia. In light of the possibility that heterotopia could affect results from behavioral studies, these data suggest that histological analyses be performed in studies of cerebellar function or development when using genetically engineered rats on these backgrounds in order to have more careful interpretation of experimental findings. PMID:25700682

  17. Animator

    ERIC Educational Resources Information Center

    Tech Directions, 2008

    2008-01-01

    Art and animation work is the most significant part of electronic game development, but is also found in television commercials, computer programs, the Internet, comic books, and in just about every visual media imaginable. It is the part of the project that makes an abstract design idea concrete and visible. Animators create the motion of life in…

  18. Genetic characterization of Giardia duodenalis by sequence analysis in humans and animals in Pemba Island, Tanzania.

    PubMed

    Di Cristanziano, V; Santoro, M; Parisi, F; Albonico, M; Shaali, M A; Di Cave, D; Berrilli, F

    2014-04-01

    Giardia duodenalis represents one of the most widespread human enteric parasites: about 200million people in Asia, Africa and Latin America are infected. Giardia exerts a deep impact on public health because of high prevalence and possible effects on growth and cognitive functions in infected children. The major aim of this study was to detect and genetically characterize G. duodenalis in both human and animal fecal samples collected in Pemba Island, in the archipelago of Zanzibar (Tanzania), in order to deepen the knowledge of genotypes of Giardia in this area. Between October 2009 and October 2010, we collected 45 human fecal samples from children from 2 primary schools and 60 animal fecal samples: 19 from zebus (Bos primigenius indicus) and 41 from goats (Capra hircus). Detection and genetic identification were performed by multilocus analysis of ssu-rDNA and gdh genes. In humans we found a higher prevalence of assemblage B (sub-assemblage BIV), in goats of assemblage E and in zebus of assemblage A. Our study represents an important contribution to the epidemiological knowledge of G. duodenalis in this area of Tanzania. PMID:24269210

  19. Progress in genetic engineering of peanut (Arachis hypogaea L.)--a review.

    PubMed

    Krishna, Gaurav; Singh, Birendra K; Kim, Eun-Ki; Morya, Vivek K; Ramteke, Pramod W

    2015-02-01

    Peanut (Arachis hypogaea L.) is a major species of the family, Leguminosae, and economically important not only for vegetable oil but as a source of proteins, minerals and vitamins. It is widely grown in the semi-arid tropics and plays a role in the world agricultural economy. Peanut production and productivity is constrained by several biotic (insect pests and diseases) and abiotic (drought, salinity, water logging and temperature aberrations) stresses, as a result of which crop experiences serious economic losses. Genetic engineering techniques such as Agrobacterium tumefaciens and DNA-bombardment-mediated transformation are used as powerful tools to complement conventional breeding and expedite peanut improvement by the introduction of agronomically useful traits in high-yield background. Resistance to several fungal, virus and insect pest have been achieved through variety of approaches ranging from gene coding for cell wall component, pathogenesis-related proteins, oxalate oxidase, bacterial chloroperoxidase, coat proteins, RNA interference, crystal proteins etc. To develop transgenic plants withstanding major abiotic stresses, genes coding transcription factors for drought and salinity, cytokinin biosynthesis, nucleic acid processing, ion antiporter and human antiapoptotic have been used. Moreover, peanut has also been used in vaccine production for the control of several animal diseases. In addition to above, this study also presents a comprehensive account on the influence of some important factors on peanut genetic engineering. Future research thrusts not only suggest the use of different approaches for higher expression of transgene(s) but also provide a way forward for the improvement of crops. PMID:25626474

  20. Animal board invited review: genetic possibilities to reduce enteric methane emissions from ruminants.

    PubMed

    Pickering, N K; Oddy, V H; Basarab, J; Cammack, K; Hayes, B; Hegarty, R S; Lassen, J; McEwan, J C; Miller, S; Pinares-Patiño, C S; de Haas, Y

    2015-09-01

    Measuring and mitigating methane (CH4) emissions from livestock is of increasing importance for the environment and for policy making. Potentially, the most sustainable way of reducing enteric CH4 emission from ruminants is through the estimation of genomic breeding values to facilitate genetic selection. There is potential for adopting genetic selection and in the future genomic selection, for reduced CH4 emissions from ruminants. From this review it has been observed that both CH4 emissions and production (g/day) are a heritable and repeatable trait. CH4 emissions are strongly related to feed intake both in the short term (minutes to several hours) and over the medium term (days). When measured over the medium term, CH4 yield (MY, g CH4/kg dry matter intake) is a heritable and repeatable trait albeit with less genetic variation than for CH4 emissions. CH4 emissions of individual animals are moderately repeatable across diets, and across feeding levels, when measured in respiration chambers. Repeatability is lower when short term measurements are used, possibly due to variation in time and amount of feed ingested prior to the measurement. However, while repeated measurements add value; it is preferable the measures be separated by at least 3 to 14 days. This temporal separation of measurements needs to be investigated further. Given the above issue can be resolved, short term (over minutes to hours) measurements of CH4 emissions show promise, especially on systems where animals are fed ad libitum and frequency of meals is high. However, we believe that for short-term measurements to be useful for genetic evaluation, a number (between 3 and 20) of measurements will be required over an extended period of time (weeks to months). There are opportunities for using short-term measurements in standardised feeding situations such as breath 'sniffers' attached to milking parlours or total mixed ration feeding bins, to measure CH4. Genomic selection has the potential to reduce both CH4 emissions and MY, but measurements on thousands of individuals will be required. This includes the need for combined resources across countries in an international effort, emphasising the need to acknowledge the impact of animal and production systems on measurement of the CH4 trait during design of experiments. PMID:26055577

  1. Chemical and genetic engineering of selective ion channel-ligand interactions.

    PubMed

    Magnus, Christopher J; Lee, Peter H; Atasoy, Deniz; Su, Helen H; Looger, Loren L; Sternson, Scott M

    2011-09-01

    Ionic flux mediates essential physiological and behavioral functions in defined cell populations. Cell type-specific activators of diverse ionic conductances are needed for probing these effects. We combined chemistry and protein engineering to enable the systematic creation of a toolbox of ligand-gated ion channels (LGICs) with orthogonal pharmacologic selectivity and divergent functional properties. The LGICs and their small-molecule effectors were able to activate a range of ionic conductances in genetically specified cell types. LGICs constructed for neuronal perturbation could be used to selectively manipulate neuron activity in mammalian brains in vivo. The diversity of ion channel tools accessible from this approach will be useful for examining the relationship between neuronal activity and animal behavior, as well as for cell biological and physiological applications requiring chemical control of ion conductance. PMID:21885782

  2. Chemical and genetic engineering of selective ligand-ion channel interactions

    PubMed Central

    Magnus, Christopher J.; Lee, Peter H.; Atasoy, Deniz; Su, Helen H.; Looger, Loren L.; Sternson, Scott M.

    2011-01-01

    Ionic flux in defined cell populations mediates essential physiological and behavioral functions. Cell type-specific activators of diverse ionic conductances are needed for probing these relationships. We combined chemistry and protein engineering to enable systematic creation of a toolbox of ligand-gated ion channels (LGICs) with orthogonal pharmacologic selectivity and divergent functional properties. The LGICs and their small molecule effectors can activate a range of ionic conductances in genetically-specified cell types. LGICs constructed for neuronal perturbation can be used to selectively manipulate neuron activity in mammalian brains in vivo. The diversity of ion channel tools accessible from this approach will be useful for examining the relationship between neuronal activity and animal behavior, as well as for cell biological and physiological applications requiring chemical control of ion conductance. PMID:21885782

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

    PubMed

    Nelson, Nicole C

    2015-07-01

    In the early 1990s, a set of new techniques for manipulating mouse DNA allowed researchers to 'knock out' specific genes and observe the effects of removing them on a live mouse. In animal behaviour genetics, questions about how to deploy these techniques to study the molecular basis of behaviour became quite controversial, with a number of key methodological issues dissecting the interdisciplinary research field along disciplinary lines. This paper examines debates that took place during the 1990s between a predominately North American group of molecular biologists and animal behaviourists around how to design, conduct, and interpret behavioural knockout experiments. Drawing from and extending Harry Collins's work on how research communities negotiate what counts as a 'well-done experiment,' I argue that the positions practitioners took on questions of experimental skill reflected not only the experimental traditions they were trained in but also their differing ontological and epistemological commitments. Different assumptions about the nature of gene action, eg., were tied to different positions in the knockout mouse debates on how to implement experimental controls. I conclude by showing that examining representations of skill in the context of a community's knowledge commitments sheds light on some of the contradictory ways in which contemporary animal behaviour geneticists talk about their own laboratory work as a highly skilled endeavour that also could be mechanised, as easy to perform and yet difficult to perform well. PMID:26090739

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

    PubMed Central

    Nelson, Nicole C.

    2015-01-01

    In the early 1990s, a set of new techniques for manipulating mouse DNA allowed researchers to ‘knock out’ specific genes and observe the effects of removing them on a live mouse. In animal behaviour genetics, questions about how to deploy these techniques to study the molecular basis of behaviour became quite controversial, with a number of key methodological issues dissecting the interdisciplinary research field along disciplinary lines. This paper examines debates that took place during the 1990s between a predominately North American group of molecular biologists and animal behaviourists around how to design, conduct, and interpret behavioural knockout experiments. Drawing from and extending Harry Collins’s work on how research communities negotiate what counts as a ‘well-done experiment,’ I argue that the positions practitioners took on questions of experimental skill reflected not only the experimental traditions they were trained in but also their differing ontological and epistemological commitments. Different assumptions about the nature of gene action, eg., were tied to different positions in the knockout mouse debates on how to implement experimental controls. I conclude by showing that examining representations of skill in the context of a community’s knowledge commitments sheds light on some of the contradictory ways in which contemporary animal behaviour geneticists talk about their own laboratory work as a highly skilled endeavour that also could be mechanised, as easy to perform and yet difficult to perform well. PMID:26090739

  5. Field Cage Studies and Progressive Evaluation of Genetically-Engineered Mosquitoes

    E-print Network

    Lloyd, Alun

    Field Cage Studies and Progressive Evaluation of Genetically-Engineered Mosquitoes Luca Facchinelli mosquito vector Aedes aegypti, designated OX3604C, was evaluated in large outdoor cage trials for its an important part of the progressive, stepwise evaluation of genetically-engineered mosquitoes. Citation

  6. Genetic Engineering: A Matter that Requires Further Refinement in Spanish Secondary School Textbooks

    ERIC Educational Resources Information Center

    Martinez-Gracia, M. V.; Gil-Quylez, M. J.; Osada, J.

    2003-01-01

    Genetic engineering is now an integral part of many high school textbooks but little work has been done to assess whether it is being properly addressed. A checklist with 19 items was used to analyze how genetic engineering is presented in biology textbooks commonly used in Spanish high schools, including the content, its relationship with…

  7. Harnessing CRISPR-Cas9 immunity for genetic engineering

    PubMed Central

    2014-01-01

    Summary CRISPR-Cas encodes an adaptive immune system that defends prokaryotes against infectious viruses and plasmids. Immunity is mediated by Cas nucleases, which use small RNA guides (the crRNAs) to specify a cleavage site within the genome of invading nucleic acids. In type II CRISPR-Cas systems, the DNA-cleaving activity is performed by a single enzyme Cas9 guided by an RNA duplex. Using synthetic single RNA guides, Cas9 can be reprogrammed to create specific double-stranded DNA breaks in the genomes of a variety of organisms, ranging from human cells to bacteria, and thus constitutes a powerful tool for genetic engineering. Here we describe recent advancements in our understanding of type II CRISPR-Cas immunity and how these studies led to revolutionary genome editing applications. PMID:25048165

  8. Ordering of Quantum Dots Using Genetically Engineered Viruses

    NASA Astrophysics Data System (ADS)

    Lee, Seung-Wuk; Mao, Chuanbin; Flynn, Christine E.; Belcher, Angela M.

    2002-05-01

    A liquid crystal system was used for the fabrication of a highly ordered composite material from genetically engineered M13 bacteriophage and zinc sulfide (ZnS) nanocrystals. The bacteriophage, which formed the basis of the self-ordering system, were selected to have a specific recognition moiety for ZnS crystal surfaces. The bacteriophage were coupled with ZnS solution precursors and spontaneously evolved a self-supporting hybrid film material that was ordered at the nanoscale and at the micrometer scale into ~72-micrometer domains, which were continuous over a centimeter length scale. In addition, suspensions were prepared in which the lyotropic liquid crystalline phase behavior of the hybrid material was controlled by solvent concentration and by the use of a magnetic field.

  9. Efficient genetic engineering of human intestinal organoids using electroporation.

    PubMed

    Fujii, Masayuki; Matano, Mami; Nanki, Kosaku; Sato, Toshiro

    2015-10-01

    Gene modification in untransformed human intestinal cells is an attractive approach for studying gene function in intestinal diseases. However, because of the lack of practical tools, such studies have largely depended upon surrogates, such as gene-engineered mice or immortalized human cell lines. By taking advantage of the recently developed intestinal organoid culture method, we developed a methodology for modulating genes of interest in untransformed human colonic organoids via electroporation of gene vectors. Here we describe a detailed protocol for the generation of intestinal organoids by culture with essential growth factors in a basement membrane matrix. We also describe how to stably integrate genes via the piggyBac transposon, as well as precise genome editing using the CRISPR-Cas9 system. Beginning with crypt isolation from a human colon sample, genetically modified organoids can be obtained in 3 weeks. PMID:26334867

  10. Harnessing CRISPR-Cas9 immunity for genetic engineering.

    PubMed

    Charpentier, Emmanuelle; Marraffini, Luciano A

    2014-06-01

    CRISPR-Cas encodes an adaptive immune system that defends prokaryotes against infectious viruses and plasmids. Immunity is mediated by Cas nucleases, which use small RNA guides (the crRNAs) to specify a cleavage site within the genome of invading nucleic acids. In type II CRISPR-Cas systems, the DNA-cleaving activity is performed by a single enzyme Cas9 guided by an RNA duplex. Using synthetic single RNA guides, Cas9 can be reprogrammed to create specific double-stranded DNA breaks in the genomes of a variety of organisms, ranging from human cells to bacteria, and thus constitutes a powerful tool for genetic engineering. Here we describe recent advancements in our understanding of type II CRISPR-Cas immunity and how these studies led to revolutionary genome editing applications. PMID:25048165

  11. Optochemical control of genetically engineered neuronal nicotinic acetylcholine receptors

    NASA Astrophysics Data System (ADS)

    Tochitsky, Ivan; Banghart, Matthew R.; Mourot, Alexandre; Yao, Jennifer Z.; Gaub, Benjamin; Kramer, Richard H.; Trauner, Dirk

    2012-02-01

    Advances in synthetic chemistry, structural biology, molecular modelling and molecular cloning have enabled the systematic functional manipulation of transmembrane proteins. By combining genetically manipulated proteins with light-sensitive ligands, innately ‘blind’ neurobiological receptors can be converted into photoreceptors, which allows them to be photoregulated with high spatiotemporal precision. Here, we present the optochemical control of neuronal nicotinic acetylcholine receptors (nAChRs) with photoswitchable tethered agonists and antagonists. Using structure-based design, we produced heteromeric ?3?4 and ?4?2 nAChRs that can be activated or inhibited with deep-violet light, but respond normally to acetylcholine in the dark. The generation of these engineered receptors should facilitate investigation of the physiological and pathological functions of neuronal nAChRs and open a general pathway to photosensitizing pentameric ligand-gated ion channels.

  12. Recombineering: genetic engineering in bacteria using homologous recombination.

    PubMed

    Thomason, Lynn C; Sawitzke, James A; Li, Xintian; Costantino, Nina; Court, Donald L

    2014-01-01

    The bacterial chromosome and bacterial plasmids can be engineered in vivo by homologous recombination using PCR products and synthetic oligonucleotides as substrates. This is possible because bacteriophage-encoded recombination proteins efficiently recombine sequences with homologies as short as 35 to 50 bases. Recombineering allows DNA sequences to be inserted or deleted without regard to location of restriction sites. This unit first describes preparation of electrocompetent cells expressing the recombineering functions and their transformation with dsDNA or ssDNA. It then presents support protocols that describe several two-step selection/counter-selection methods of making genetic alterations without leaving any unwanted changes in the targeted DNA, and a method for retrieving onto a plasmid a genetic marker (cloning by retrieval) from the Escherichia coli chromosome or a co-electroporated DNA fragment. Additional protocols describe methods to screen for unselected mutations, removal of the defective prophage from recombineering strains, and other useful techniques. Curr. Protoc. Mol. Biol. 106:1.16.1-1.16.39. © 2014 by John Wiley & Sons, Inc. PMID:24733238

  13. A FIELD STUDY WITH GENETICALLY ENGINEERED ALFALFA INOCULATED WITH RECOMBINANT SINORHIZOBIUM MELILOTI: EFFECTS ON THE SOIL ECOSYSTEM

    EPA Science Inventory

    The agricultural use of genetically engineered plants and microorganisms has become increasingly common. Because genetically engineered plants and microorganisms can produce compounds foreign to their environment, there is concern that they may become established outside of thei...

  14. 78 FR 51706 - Bayer CropScience LP; Determination of Nonregulated Status of Soybean Genetically Engineered for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-21

    ...Organisms and Products Altered or Produced Through Genetic Engineering Which Are Plant Pests or Which There Is Reason to...organisms and products altered or produced through genetic engineering that are plant pests or that there is reason...

  15. 76 FR 63278 - Bayer CropScience LP; Determination of Nonregulated Status for Cotton Genetically Engineered for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-12

    ...Organisms and Products Altered or Produced Through Genetic Engineering Which Are Plant Pests or Which There Is Reason to...organisms and products altered or produced through genetic engineering that are plant pests or that there is reason...

  16. Teaching Habitat and Animal Classification to Fourth Graders Using an Engineering-Design Model

    ERIC Educational Resources Information Center

    Marulcu, Ismail

    2014-01-01

    Background: The motivation for this work is built upon the premise that there is a need for research-based materials for design-based science instruction. In this paper, a small portion of our work investigating the impact of a LEGO[TM] engineering unit on fourth grade students' preconceptions and understanding of animals is presented.…

  17. Genetic engineering strategies to prevent the effects of antibody and complement on xenogeneic chondrocytes.

    PubMed

    Sommaggio, R; Bello-Gil, D; Pérez-Cruz, M; Brokaw, J L; Máñez, R; Costa, C

    2015-01-01

    Advances in animal transgenesis may allow using xenogeneic chondrocytes in tissue-engineering applications for clinical cartilage repair. Porcine cartilage is rejected by humoral and cellular mechanisms that could be overcome by identifying key molecules triggering rejection and developing effective genetic-engineering strategies. Accordingly, high expression of ?1,2-fucosyltransferase (HT) in xenogeneic cartilage protects from galactose ?1,3-galactose (Gal)-mediated antibody responses. Now, we studied whether expression of a complement inhibitor provides further protection. First, porcine articular chondrocytes (PAC) were isolated from non-transgenic, single and double transgenic pigs expressing HT and moderate levels of human CD59 (hCD59) and their response to human serum was assessed. High recombinant expression of human complement regulatory molecules hCD59 and hDAF was also attained by retroviral transduction of PAC for further analyses. Complement activation on PAC after exposure to 20 % human serum for 24 hours mainly triggered the release of pro-inflammatory cytokines IL-6 and IL-8. Transgenic expression of HT and hCD59 did not suffice to fully counteract this effect. Nevertheless, the combination of blocking anti-Gal antibodies (or C5a) and high hCD59 levels conferred very high protection. On the contrary, high hDAF expression attained the most dramatic reduction in IL-6/IL-8 secretion by a single strategy, but the additional inhibition of anti-Gal antibodies or C5a did not provide further improvement. Notably, we demonstrate that both hCD59 and hDAF inhibit anaphylatoxin release in this setting. In conclusion, our study identifies genetic-engineering approaches to prevent humoral rejection of xenogeneic chondrocytes for use in cartilage repair. PMID:26579969

  18. Genetic causes of transitions from sexual reproduction to asexuality in plants and animals.

    PubMed

    Neiman, M; Sharbel, T F; Schwander, T

    2014-07-01

    The persistence of sexual reproduction in the face of competition from asexual invaders is more likely if asexual lineages are produced infrequently or have low fitness. The generation rate and success of new asexual lineages will be influenced by the proximate mechanisms underlying transitions to asexuality. As such, characterization of these mechanisms can help explain the distribution of reproductive modes among natural populations. Here, we synthesize the literature addressing proximate causes of transitions from sexual to asexual reproduction in plants and animals. In cyclical and facultatively asexual taxa, individual mutations can cause obligate asexuality. The evolution of asexuality in obligately sexual groups is more complex, requiring the simultaneous acquisition of two traits generally controlled by different genetic factors: unreduced gamete formation and spontaneous development of unfertilized gametes. At least three 'pre-adaptations' could favour transitions to obligate asexuality in obligate sexuals. First, linkage among loci affecting separate key components of asexuality facilitates its spread, with evidence for these linkage blocks in plants. Second, asexuality should evolve more readily in haplodiploids; support for this hypothesis comes from two examples where a single locus causes transitions to asexuality. Third, standing genetic variation for the production of unreduced gametes could facilitate transitions to asexuality, but whether the ability to produce unreduced gametes contributes to the evolution of obligate asexuality remains unclear. We close by reviewing the associations between asexuality, hybridization and polyploidy, and argue that current data suggest that hybridization is more likely to play a causal role in transitions to asexuality than polyploidy. PMID:24666600

  19. Reward circuitry dysfunction in psychiatric and neurodevelopmental disorders and genetic syndromes: animal models and clinical findings

    PubMed Central

    2012-01-01

    This review summarizes evidence of dysregulated reward circuitry function in a range of neurodevelopmental and psychiatric disorders and genetic syndromes. First, the contribution of identifying a core mechanistic process across disparate disorders to disease classification is discussed, followed by a review of the neurobiology of reward circuitry. We next consider preclinical animal models and clinical evidence of reward-pathway dysfunction in a range of disorders, including psychiatric disorders (i.e., substance-use disorders, affective disorders, eating disorders, and obsessive compulsive disorders), neurodevelopmental disorders (i.e., schizophrenia, attention-deficit/hyperactivity disorder, autism spectrum disorders, Tourette’s syndrome, conduct disorder/oppositional defiant disorder), and genetic syndromes (i.e., Fragile X syndrome, Prader–Willi syndrome, Williams syndrome, Angelman syndrome, and Rett syndrome). We also provide brief overviews of effective psychopharmacologic agents that have an effect on the dopamine system in these disorders. This review concludes with methodological considerations for future research designed to more clearly probe reward-circuitry dysfunction, with the ultimate goal of improved intervention strategies. PMID:22958744

  20. Genetic Improvement for Adaptive Software Engineering Mark Harman, Yue Jia, William B. Langdon, Justyna Petke, Iman Hemati Moghadam,

    E-print Network

    Harman, Mark

    Genetic Improvement for Adaptive Software Engineering Mark Harman, Yue Jia, William B. Langdon engineer. In this paper we outline how a Search Based Software Engineering approach called `genetic ABSTRACT This paper1 presents a brief outline of an approach to online genetic improvement. We argue

  1. QUERY DRIVEN SIMULATION AS A TOOL FOR GENETIC ENGINEERS John A. Miller+, Jonathan Arnold#, Krys J. Kochut+,

    E-print Network

    Miller, John A.

    QUERY DRIVEN SIMULATION AS A TOOL FOR GENETIC ENGINEERS John A. Miller+, Jonathan Arnold#, Krys J simulation/object­oriented database system that can be used by genetic engineers to understand better a solid foundation for Computer­Aided Genetic Engineering (CAGE). 1. INTRODUCTION Storing genome mapping

  2. Exploring Dynamics of Molybdate in Living Animal Cells by a Genetically Encoded FRET Nanosensor

    PubMed Central

    Nakanishi, Yoichi; Iida, Syuntaro; Ueoka-Nakanishi, Hanayo; Niimi, Tomoaki; Tomioka, Rie; Maeshima, Masayoshi

    2013-01-01

    Molybdenum (Mo) is an essential trace element for almost all living organisms including animals. Mo is used as a catalytic center of molybdo-enzymes for oxidation/reduction reactions of carbon, nitrogen, and sulfur metabolism. Whilst living cells are known to import inorganic molybdate oxyanion from the surrounding environment, the in vivo dynamics of cytosolic molybdate remain poorly understood as no appropriate indicator is available for this trace anion. We here describe a genetically encoded Förester-resonance-energy-transfer (FRET)-based nanosensor composed of CFP, YFP and the bacterial molybdate-sensor protein ModE. The nanosensor MolyProbe containing an optimized peptide-linker responded to nanomolar-range molybdate selectively, and increased YFP:CFP fluorescence intensity ratio by up to 109%. By introduction of the nanosensor, we have been able to successfully demonstrate the real-time dynamics of molybdate in living animal cells. Furthermore, time course analyses of the dynamics suggest that novel oxalate-sensitive- and sulfate-resistant- transporter(s) uptake molybdate in a model culture cell. PMID:23472155

  3. Practical Training in Microalgae Utilization with Key Industry Engineering Group Key Industry Engineering Group s.r.o. has developed a biotechnology for the production of an animal

    E-print Network

    Practical Training in Microalgae Utilization with Key Industry Engineering Group Key Industry Engineering Group s.r.o. has developed a biotechnology for the production of an animal feed product based medium which is then applied directly to the animals during feeding. The use of this suspension has shown

  4. Non-genetic engineering of cells for drug delivery and cell-based therapy.

    PubMed

    Wang, Qun; Cheng, Hao; Peng, Haisheng; Zhou, Hao; Li, Peter Y; Langer, Robert

    2015-08-30

    Cell-based therapy is a promising modality to address many unmet medical needs. In addition to genetic engineering, material-based, biochemical, and physical science-based approaches have emerged as novel approaches to modify cells. Non-genetic engineering of cells has been applied in delivering therapeutics to tissues, homing of cells to the bone marrow or inflammatory tissues, cancer imaging, immunotherapy, and remotely controlling cellular functions. This new strategy has unique advantages in disease therapy and is complementary to existing gene-based cell engineering approaches. A better understanding of cellular systems and different engineering methods will allow us to better exploit engineered cells in biomedicine. Here, we review non-genetic cell engineering techniques and applications of engineered cells, discuss the pros and cons of different methods, and provide our perspectives on future research directions. PMID:25543006

  5. Genetic analysis of calving traits by the multi-trait individual animal model.

    PubMed

    Weller, J I; Ezra, E

    2016-01-01

    Five alternative models were applied for analysis of dystocia and stillbirth in first and second parities. Models 1 and 2 were included only to estimate the parameters required for model 4, and models 3 and 5 are included only as comparisons to the model 4 estimates. Variance components were estimated by multi-trait REML, including cows with valid calving records for both parities. For the effects of sire of calf on first and second parities, variance components were estimated including only calvings with the same sire of calf for both parities. All heritabilities for the cow effect were quite low, but higher for dystocia than for stillbirth and higher in first parity. The sire-of-calf heritabilities were higher than the cow effect heritabilities, except for stillbirth in parity 2. Unlike the effect of cow correlations, all sire of calf correlations were >0.6, and the correlations for the same trait in parities 1 and 2 were >0.9. Thus, a multi-trait analysis should yield a significant gain in accuracy with respect to the sire of calf effects for bulls not mated to virgin heifers. A multi-trait individual animal model algorithm was developed for joint analysis of dystocia and stillbirth in first and second parities. Relationships matrices were included both for the effects of cow and sire of calf. In addition, random herd-year-season and fixed sex of calf effects were included in the model. Records were preadjusted for calving month and age. A total of 899,223 Israeli Holstein cows with first calvings since 1985 were included in the complete analysis. Approximate reliabilities were computed for both sire of cow and sire of calf effects. Correlations between these reliabilities and reliabilities obtained by direct inversion of the coefficient matrix for a sire of cow-sire of calf model were all close to 0.99. Phenotypic trends for cows born from 1983 through 2007 were economically unfavorable for dystocia and favorable for stillbirth in both parities. Genetic trends were economically unfavorable for both dystocia and stillbirth in first parity. First-parity sire of calf trends were unfavorable for dystocia, but favorable for stillbirth. All environmental trends were nearly zero. Regressions of evaluations of the complete analysis on a model including only calvings before 2011 were all >0.8. All evaluations met the Interbull Method 3 criterion for unbiasedness. Model 4, which computed genetic evaluations for all animals for all 4 traits accounting for all known relationships and correlations among the traits, is recommended for routine genetic evaluation of calving traits. PMID:26547643

  6. Quantitative Assessment of In Vivo HIV Protease Activity Using Genetically Engineered QD-Based

    E-print Network

    Chen, Wilfred

    Quantitative Assessment of In Vivo HIV Protease Activity Using Genetically Engineered QD-Based FRET Department of Chemical and Environmental Engineering, University of California, Riverside, California 2 of Chemical and Biomolecular Engineering, University of Delaware, Newark, Delaware 19716; telephone: þ1

  7. 44 SCIENTIFIC AMERICAN JUNE 2006 lthough the term "genetic engineering" has been in

    E-print Network

    Robins, Gabriel

    44 SCIENTIFIC AMERICAN JUNE 2006 A lthough the term "genetic engineering" has been in use of an approach to biotechnology modeled on electronics engineering. Principles and practices learned from engineering successes can help transform biotechnology from a specialized craft into a mature industry

  8. Stochastic signaling in biochemical cascades and genetic systems in genetically engineered living cells

    NASA Astrophysics Data System (ADS)

    Daniel, Ramiz; Almog, Ronen; Shacham-Diamand, Yosi

    2010-04-01

    Living cells, either prokaryote or eukaryote, can be integrated within whole-cell biochips (WCBCs) for various applications. We investigate WCBCs where information is extracted from the cells via a cascade of biochemical reactions that involve gene expression. The overall biological signal is weak due to small sample volume, low intrinsic cell response, and extrinsic signal loss mechanisms. The low signal-to-noise ratio problem is aggravated during initial detection stages and limits the minimum detectable signal or, alternatively, the minimum detection time. Taking into account the stochastic nature of biochemical process, we find that the signal is accompanied by relatively large noise disturbances. In this work, we use genetically engineered microbe sensors as a model to study the biochips output signal stochastic behavior. In our model, the microbes are designed to express detectable reporter proteins under external induction. We present analytical approximated expressions and numerical simulations evaluating the fluctuations of the synthesized reporter proteins population based on a set of equations modeling a cascade of biochemical and genetic reactions. We assume that the reporter proteins decay more slowly than messenger RNA molecules. We calculate the relation between the noise of the input signal (extrinsic noise) and biochemical reaction statistics (intrinsic noise). We discuss in further details two cases: (1) a cascade with large decay rates of all biochemical reactions compared to the protein decay rate. We show that in this case, the noise amplitude has a positive linear correlation with the number of stages in the cascade. (2) A cascade which includes a stable enzymatic-binding reaction with slow decay rate. We show that in this case, the noise strongly depends on the protein decay rate. Finally, a general observation is presented stating that the noise in whole-cell biochip sensors is determined mainly by the first reactions in the genetic system with weak dependence on the number of stages in the cascade.

  9. Genetically-engineered Newcastle Disease Virus for malignant melanoma therapy

    PubMed Central

    Zamarin, Dmitriy; Vigil, Adam; Kelly, Kaitlyn; García-Sastre, Adolfo; Fong, Yuman

    2010-01-01

    SUMMARY Despite the advances in cancer therapies in the past century, malignant melanoma continues to present a significant clinical challenge due to lack of chemotherapeutic response. Systemic therapy with immunostimulatory agents such as interferon and interleukin-2 (IL-2) has shown some promise, though each is associated with significant side effects. Over the past 50 years, oncolytic Newcastle Disease Virus (NDV) has emerged as an alternative candidate for cancer therapy. The establishment of reverse-genetics systems for the virus has allowed us to further manipulate the virus to enhance its oncolytic activity. Introduction of immunomodulatory molecules, especially IL-2, into the NDV genome was shown to enhance the oncolytic potential of the virus in a murine syngeneic colon carcinoma model. We hypothesize that a recombinant NDV expressing IL-2 would be an effective agent for therapy of malignant melanoma. We show that recombinant NDV possesses a strong cytolytic activity against multiple melanoma cell lines, and is effective in clearing established syngeneic melanoma tumors in mice. Moreover, introduction of murine IL-2 into NDV significantly enhanced its activity against syngeneic melanomas, resulting in increased overall animal survival and generation of anti-tumor immunity. These findings warrant further investigations of IL-2-expressing NDV as an anti-melanoma agent in humans. PMID:19242529

  10. Genetic Animal Models of Depression Peter R. Canavello, Rupert J. Egan, Carisa L. Bergner, Peter C. Hart,

    E-print Network

    Kalueff, Allan V.

    191 Chapter 10 Genetic Animal Models of Depression Peter R. Canavello, Rupert J. Egan, Carisa L. Bergner, Peter C. Hart, Jonathan M. Cachat, and Allan V. Kalueff Abstract Depression, as part of a larger diseases. However, much remains to be discovered concerning depression, due to the daunting complexity

  11. A COMPARISON OF SIRE AND ANIMAL MODEL GENETIC PARAMETER ESTIMATES FROM HERDS WITH HIGH AND LOW WITHIN-HERD HERITABILITIES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objectives of this study were to determine if within-herd heritability (WHH) estimated with regression techniques accurately reflects heritability (h2) differences among herds and to compare sire and animal model genetic parameter estimates among herds varying in WHH. Milk, fat, and protein yiel...

  12. Genetically modified animals from life-science, socio-economic and ethical perspectives: examining issues in an EU policy context.

    PubMed

    Frewer, L J; Kleter, G A; Brennan, M; Coles, D; Fischer, A R H; Houdebine, L M; Mora, C; Millar, K; Salter, B

    2013-06-25

    The interdisciplinary EC consortium (the PEGASUS project) aimed to examine the issues raised by the development, implementation and commercialisation of genetically modified (GM) animals, and derivative foods and pharmaceutical products. The results integrated existing social (including existing public perception) environmental and economic knowledge regarding GM animals to formulate policy recommendations relevant to new developments and applications. The use of GM in farmed animals (aquatic, terrestrial and pharmaceutical) was mapped and reviewed. A foresight exercise was conducted to identity future developments. Three case studies (aquatic, terrestrial and pharmaceutical) were applied to identify the issues raised, including the potential risks and benefits of GM animals from the perspectives of the production chain (economics and agri-food sector) and the life sciences (human and animal health, environmental impact, animal welfare and sustainable production). Ethical and policy concerns were examined through application of combined ethical matrix method and policy workshops. The case studies were also used to demonstrate the utility of public engagement in the policy process. The results suggest that public perceptions, ethical issues, the competitiveness of EU animal production and risk-benefit assessments that consider human and animal health, environmental impact and sustainable production need to be considered in EU policy development. Few issues were raised with application in the pharmaceutical sector, assuming ethical and economic issues were addressed in policy, but the introduction of agricultural GM animal applications should be considered on a case-by-case basis. PMID:23567982

  13. Distributed Classifier Based on Genetically Engineered Bacterial Cell Cultures

    PubMed Central

    2015-01-01

    We describe a conceptual design of a distributed classifier formed by a population of genetically engineered microbial cells. The central idea is to create a complex classifier from a population of weak or simple classifiers. We create a master population of cells with randomized synthetic biosensor circuits that have a broad range of sensitivities toward chemical signals of interest that form the input vectors subject to classification. The randomized sensitivities are achieved by constructing a library of synthetic gene circuits with randomized control sequences (e.g., ribosome-binding sites) in the front element. The training procedure consists in reshaping of the master population in such a way that it collectively responds to the “positive” patterns of input signals by producing above-threshold output (e.g., fluorescent signal), and below-threshold output in case of the “negative” patterns. The population reshaping is achieved by presenting sequential examples and pruning the population using either graded selection/counterselection or by fluorescence-activated cell sorting (FACS). We demonstrate the feasibility of experimental implementation of such system computationally using a realistic model of the synthetic sensing gene circuits. PMID:25349924

  14. Genetically engineered protein in hydrogels tailors stimuli-responsive characteristics

    NASA Astrophysics Data System (ADS)

    Ehrick, Jason D.; Deo, Sapna K.; Browning, Tyler W.; Bachas, Leonidas G.; Madou, Marc J.; Daunert, Sylvia

    2005-04-01

    Certain proteins undergo a substantial conformational change in response to a given stimulus. This conformational change can manifest in different manners and result in an actuation, that is, catalytic or signalling event, movement, interaction with other proteins, and so on. In all cases, the sensing-actuation process of proteins is initiated by a recognition event that translates into a mechanical action. Thus, proteins are ideal components for designing new nanomaterials that are intelligent and can perform desired mechanical actions in response to target stimuli. A number of approaches have been undertaken to mimic nature's sensing-actuating process. We now report a new hybrid material that integrates genetically engineered proteins within hydrogels capable of producing a stimulus-responsive action mechanism. The mechanical effect is a result of an induced conformational change and binding affinities of the protein in response to a stimulus. The stimuli-responsive hydrogel exhibits three specific swelling stages in response to various ligands offering additional fine-tuned control over a conventional two-stage swelling hydrogel. The newly prepared material was used in the sensing, and subsequent gating and transport of biomolecules across a polymer network, demonstrating its potential application in microfluidics and miniaturized drug-delivery systems.

  15. Genetic engineering of yellow betalain pigments beyond the species barrier

    PubMed Central

    Nakatsuka, Takashi; Yamada, Eri; Takahashi, Hideyuki; Imamura, Tomohiro; Suzuki, Mariko; Ozeki, Yoshihiro; Tsujimura, Ikuko; Saito, Misa; Sakamoto, Yuichi; Sasaki, Nobuhiro; Nishihara, Masahiro

    2013-01-01

    Betalains are one of the major plant pigment groups found in some higher plants and higher fungi. They are not produced naturally in any plant species outside of the order Caryophyllales, nor are they produced by anthocyanin-accumulating Caryophyllales. Here, we attempted to reconstruct the betalain biosynthetic pathway as a self-contained system in an anthocyanin-producing plant species. The combined expressions of a tyrosinase gene from shiitake mushroom and a DOPA 4,5-dioxygenase gene from the four-o'clock plant resulted in successful betalain production in cultured cells of tobacco BY2 and Arabidopsis T87. Transgenic tobacco BY2 cells were bright yellow because of the accumulation of betaxanthins. LC-TOF-MS analyses showed that proline-betaxanthin (Pro-Bx) accumulated as the major betaxanthin in these transgenic BY2 cells. Transgenic Arabidopsis T87 cells also produced betaxanthins, but produced lower levels than transgenic BY2 cells. These results illustrate the success of a novel genetic engineering strategy for betalain biosynthesis. PMID:23760173

  16. Production and characterization of genetically engineered antibody molecules.

    PubMed

    Morrison, S L; Canfield, S; Porter, S; Tan, L K; Tao, M H; Wims, L A

    1988-09-01

    Expression of antibody heavy- and light-chain genes by transfection permits the production of monoclonal antibodies with improved biological and antigen-binding properties. The immunoglobulin genes are placed in vectors containing a gene for encoding a protein that provides a biochemically selectable function in eukaryotic cells; these vectors are transfected into myeloma and hybridoma cells. Selection of drug-resistant cells permits the efficient isolation of the rare cells that express the transfected DNA. By placing heavy and light chains on plasmids with different selectable markers, one can deliver heavy- and light-chain genes simultaneously to the same cell. The transfected immunoglobulin genes are efficiently expressed and the proteins produced are a faithful mirror of the genes that were introduced. Using the standard techniques of genetic engineering and gene transfection, we can now produce antibodies of widely varying structures, including chimeric antibodies with segments derived from different species. These antibodies provide useful reagents to study structure-function relationships within the antibody molecule. Ultimately it will be possible to produce a new generation of antibody molecules with improved antigen-binding properties and effector functions. PMID:3138036

  17. Genetically engineered protein in hydrogels tailors stimuli-responsive characteristics.

    PubMed

    Ehrick, Jason D; Deo, Sapna K; Browning, Tyler W; Bachas, Leonidas G; Madou, Marc J; Daunert, Sylvia

    2005-04-01

    Certain proteins undergo a substantial conformational change in response to a given stimulus. This conformational change can manifest in different manners and result in an actuation, that is, catalytic or signalling event, movement, interaction with other proteins, and so on. In all cases, the sensing-actuation process of proteins is initiated by a recognition event that translates into a mechanical action. Thus, proteins are ideal components for designing new nanomaterials that are intelligent and can perform desired mechanical actions in response to target stimuli. A number of approaches have been undertaken to mimic nature's sensing-actuating process. We now report a new hybrid material that integrates genetically engineered proteins within hydrogels capable of producing a stimulus-responsive action mechanism. The mechanical effect is a result of an induced conformational change and binding affinities of the protein in response to a stimulus. The stimuli-responsive hydrogel exhibits three specific swelling stages in response to various ligands offering additional fine-tuned control over a conventional two-stage swelling hydrogel. The newly prepared material was used in the sensing, and subsequent gating and transport of biomolecules across a polymer network, demonstrating its potential application in microfluidics and miniaturized drug-delivery systems. PMID:15765106

  18. Genetically engineered microorganisms for the detection of explosives’ residues

    PubMed Central

    Shemer, Benjamin; Palevsky, Noa; Yagur-Kroll, Sharon; Belkin, Shimshon

    2015-01-01

    The manufacture and use of explosives throughout the past century has resulted in the extensive pollution of soils and groundwater, and the widespread interment of landmines imposes a major humanitarian risk and prevents civil development of large areas. As most current landmine detection technologies require actual presence at the surveyed areas, thus posing a significant risk to personnel, diverse research efforts are aimed at the development of remote detection solutions. One possible means proposed to fulfill this objective is the use of microbial bioreporters: genetically engineered microorganisms “tailored” to generate an optical signal in the presence of explosives’ vapors. The use of such sensor bacteria will allow to pinpoint the locations of explosive devices in a minefield. While no study has yet resulted in a commercially operational system, significant progress has been made in the design and construction of explosives-sensing bacterial strains. In this article we review the attempts to construct microbial bioreporters for the detection of explosives, and analyze the steps that need to be undertaken for this strategy to be applicable for landmine detection. PMID:26579085

  19. An animal model for the study of the genetic bases of behaviour in men: the multiple marker strains (MMS).

    PubMed

    Clément, Y; Lepicard, E; Chapouthier, G

    2001-06-01

    Animal models are often used for preclinical research on the neurobiology of psychiatric disorders. Whereas many are employed to screen new therapeutic agents, few of them are used to study the genetic bases of psychiatric diseases, probably because of the complex genetic determinism underlying quantitative behavioral traits such as mood, personality or intelligence. The present article presents a short review introducing an analysis model using mice: the marker strains model. Using this model it is possible both to display genetic determinism data and to locate some of the chromosomal fragments involved in the regulation of anxiogenic processes. At present it cannot accurately determine the position of one or more genes, but it does provide a valuable means of 'scanning' the genome for an approximation. Through genetic analysis, using the model, an attempt will be made to identify autosomal fragments which may be involved in two behavioural traits: anxiety and chemical-induced seizures. In this paper, after reviewing theoretical aspects of looking for genes involved in behaviour, we will successively introduce studies in genetic topics in psychiatric human studies as well as appropriated behavioural animal studies. Then we will present a genetic model in mice which allows us to locate chromosomal fragments associated with a behavioural trait: multiple marker strains. PMID:11418276

  20. Genetic algorithm based optimization in engineering design using fuzzy constraints and fitness functions 

    E-print Network

    Vijayakumar, Bhuvaneshwaran

    2001-01-01

    The motivation for this work has been the use of tools, such as genetic algorithms and fuzzy sets, to address the various issues that are involved in an engineering design optimization problem. In order to address the variety, generality...

  1. The establishment of genetically engineered canola populations in the U.S.

    EPA Science Inventory

    Concerns regarding the commercial release of genetically engineered (GE) crops include naturalization, introgression to sexually compatible relatives and the transfer of beneficial traits to native and weedy species through hybridization. To date there have been few documented re...

  2. SURVIVAL DIFFERENCES AMONG FREEZE-DRIED GENETICALLY ENGINEERED AND WILD-TYPE BACTERIA

    EPA Science Inventory

    Spray application is often used to introduce genetically engineered microorganisms into the environment. he risk associated with the downwind transport and survival necessitates development of tools to assess the risk associated with their airborne transport. ecause the death mec...

  3. USE OF A NOVEL PLASMID TO MONITOR THE FATE OF A GENETICALLY ENGINEERED PSEUDOMONAS PUTIDA STRAIN

    EPA Science Inventory

    Plasmid pSI30 was constructed to increase the sensitivity of detection of a genetically engineered microorganism (GEM) and its recombinant DNA in environmental samples. his broad host-range, mobilizable plasmid contained chlorocatechol (clc) degradative genes, antibiotic resistan...

  4. Gene flow in genetically engineered perennial grasses: Lessons for modification of dedicated bioenergy crops

    EPA Science Inventory

    The potential ecological consequences of the commercialization of genetically engineered (GD) crops have been the subject of intense debate, particularly when the GE crops are perennial and capable of outcrossing to wild relatives. The essential ecological impact issues for engi...

  5. A 3D character animation engine for multimodal interaction on mobile devices

    NASA Astrophysics Data System (ADS)

    Sandali, Enrico; Lavagetto, Fabio; Pisano, Paolo

    2005-03-01

    Talking virtual characters are graphical simulations of real or imaginary persons that enable natural and pleasant multimodal interaction with the user, by means of voice, eye gaze, facial expression and gestures. This paper presents an implementation of a 3D virtual character animation and rendering engine, compliant with the MPEG-4 standard, running on Symbian-based SmartPhones. Real-time animation of virtual characters on mobile devices represents a challenging task, since many limitations must be taken into account with respect to processing power, graphics capabilities, disk space and execution memory size. The proposed optimization techniques allow to overcome these issues, guaranteeing a smooth and synchronous animation of facial expressions and lip movements on mobile phones such as Sony-Ericsson's P800 and Nokia's 6600. The animation engine is specifically targeted to the development of new "Over The Air" services, based on embodied conversational agents, with applications in entertainment (interactive story tellers), navigation aid (virtual guides to web sites and mobile services), news casting (virtual newscasters) and education (interactive virtual teachers).

  6. Genetic engineering of Ganoderma lucidum for the efficient production of ganoderic acids.

    PubMed

    Xu, Jun-Wei; Zhong, Jian-Jiang

    2015-11-01

    Ganoderma lucidum is a well-known traditional medicinal mushroom that produces ganoderic acids with numerous interesting bioactivities. Genetic engineering is an efficient approach to improve ganoderic acid biosynthesis. However, reliable genetic transformation methods and appropriate genetic manipulation strategies remain underdeveloped and thus should be enhanced. We previously established a homologous genetic transformation method for G. lucidum; we also applied the established method to perform the deregulated overexpression of a homologous 3-hydroxy-3-methyl-glutaryl coenzyme A reductase gene in G. lucidum. Engineered strains accumulated more ganoderic acids than wild-type strains. In this report, the genetic transformation systems of G. lucidum are described; current trends are also presented to improve ganoderic acid production through the genetic manipulation of G. lucidum. PMID:26588475

  7. Teaching Applied Genetics and Molecular Biology to Agriculture Engineers. Application of the European Credit Transfer System

    ERIC Educational Resources Information Center

    Weiss, J.; Egea-Cortines, M.

    2008-01-01

    We have been teaching applied molecular genetics to engineers and adapted the teaching methodology to the European Credit Transfer System. We teach core principles of genetics that are universal and form the conceptual basis of most molecular technologies. The course then teaches widely used techniques and finally shows how different techniques…

  8. Scientific and regulatory challenges of developing a genetically engineered virus resistant plum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Genetic engineering (GE) has the potential to revolutionize fruit tree breeding and is an important addition to the fruit breeder’s "toolbox". It is an approach that can specifically target genetic improvements and allow for the development of novel, useful traits. In spite of the potential utilit...

  9. Genetical Engineering of Handwriting Representations Alexandre Lemieux, Christian Gagne and Marc Parizeau

    E-print Network

    Fernandez, Thomas

    generation, and on the second hand, genetic operators that modify current solutions. The application of GPGenetical Engineering of Handwriting Representations Alexandre Lemieux, Christian Gagn´e and Marc}@gel.ulaval.ca Abstract This paper presents experiments with genetically engi- neered feature sets for recognition of on

  10. The Significance of Content Knowledge for Informal Reasoning regarding Socioscientific Issues: Applying Genetics Knowledge to Genetic Engineering Issues

    ERIC Educational Resources Information Center

    Sadler, Troy D.; Zeidler, Dana L.

    2005-01-01

    This study focused on informal reasoning regarding socioscientific issues. It sought to explore how content knowledge influenced the negotiation and resolution of contentious and complex scenarios based on genetic engineering. Two hundred and sixty-nine students drawn from undergraduate natural science and nonnatural science courses completed a…

  11. Genetically engineered ER?-positive breast cancer mouse models.

    PubMed

    Dabydeen, Sarah A; Furth, Priscilla A

    2014-06-01

    The majority of human breast cancers are estrogen receptor-positive (ER+), but this has proven challenging to model in genetically engineered mice. This review summarizes information on 21 mouse models that develop ER+ mammary cancer. Where available, information on cancer pathology and gene expression profiles is referenced to assist in understanding which histological subtype of ER+ human cancer each model might represent. ESR1, CCDN1, prolactin, TGF?, AIB1, ESPL1, and WNT1 overexpression, PIK3CA gain of function, as well as loss of P53 (Trp53) or STAT1 are associated with ER+ mammary cancer. Treatment with the PPAR? agonist efatutazone in a mouse with Brca1 and p53 deficiency and 7,12-dimethylbenz(a)anthracene exposure in combination with an activated myristoylated form of AKT1 also induce ER+ mammary cancer. A spontaneous mutant in nude mice that develops metastatic ER+ mammary cancer is included. Age of cancer development ranges from 3 to 26 months and the percentage of cancers that are ER+ vary from 21 to 100%. Not all models are characterized as to their estrogen dependency and/or response to anti-hormonal therapy. Strain backgrounds include C57Bl/6, FVB, BALB/c, 129S6/SvEv, CB6F1, and NIH nude. Most models have only been studied on one strain background. In summary, while a range of models are available for studies of pathogenesis and therapy of ER+ breast cancers, many could benefit from further characterization, and opportunity for development of new models remains. PMID:24481326

  12. The feasibility of ureteral tissue engineering using autologous veins: an orthotopic animal model with long term results

    PubMed Central

    2014-01-01

    Background In an earlier study we demonstrated the feasibility to create tissue engineered venous scaffolds in vitro and in vivo. In this study we investigated the use of tissue engineered constructs for ureteral replacement in a long term orthotopic minipig model. In many different projects well functional ureretal tissue was established using tissue engineering in animals with short-time follow up (12 weeks). Therefore urothelial cells were harvested from the bladder, cultured, expanded in vitro, labelled with fluorescence and seeded onto the autologous veins, which were harvested from animals during a second surgery. Three days after cell seeding the right ureter was replaced with the cell-seeded matrices in six animals, while further 6 animals received an unseeded vein for ureteral replacement. The animals were sacrificed 12, 24, and 48 weeks after implantation. Gross examination, intravenous pyelogram (IVP), H&E staining, Trichrome Masson’s Staining, and immunohistochemistry with pancytokeratin AE1/AE3, smooth muscle alpha actin, and von Willebrand factor were performed in retrieved specimens. Results The IVP and gross examination demonstrated that no animals with tissue engineered ureters and all animals of the control group presented with hydronephrosis after 12 weeks. In the 24-week group, one tissue engineered and one unseeded vein revealed hydronephrosis. After 48 weeks all tissue engineered animals and none of the control group showed hydronephrosis on the treated side. Histochemistry and immunohistochemistry revealed a multilayer of urothelial cells attached to the seeded venous grafts. Conclusions Venous grafts may be a potential source for ureteral reconstruction. The results of so far published ureteral tissue engineering projects reveal data up to 12 weeks after implantation. Even if the animal numbers of this study are small, there is an increasing rate of hydronephrosis revealing failure of ureteral tissue engineering with autologous matrices in time points longer than 3 months after implantation. Further investigations have to prove adequate clinical outcome and appropriate functional long-term results. PMID:25381044

  13. Generating Alternative Engineering Designs by Integrating Desktop VR with Genetic Algorithms

    ERIC Educational Resources Information Center

    Chandramouli, Magesh; Bertoline, Gary; Connolly, Patrick

    2009-01-01

    This study proposes an innovative solution to the problem of multiobjective engineering design optimization by integrating desktop VR with genetic computing. Although, this study considers the case of construction design as an example to illustrate the framework, this method can very much be extended to other engineering design problems as well.…

  14. Escherichia coli K5 heparosan fermentation and improvement by genetic engineering

    PubMed Central

    Wang, Zhenyu; Linhardt, Robert J

    2011-01-01

    N-acetyl heparosan is the precursor for the biosynthesis of the important anticoagulant drug heparin. The Escherichia coli K5 capsular heparosan polysaccharide provides a promising precursor for in vitro chemoenzymatic production of bioengineered heparin. This article explores the improvements of heparosan production for bioengineered heparin by fermentation process engineering and genetic engineering. PMID:21636991

  15. Genetically Engineered Elastin-Protein A Fusion as a Universal Platform for Homogeneous,

    E-print Network

    Chen, Wilfred

    Genetically Engineered Elastin-Protein A Fusion as a Universal Platform for Homogeneous, Phase and Environmental Engineering and Environmental Toxicology Graduate Program, University of California, Riverside, California 92521, and Hawaii Biotech Inc., Aiea, Hawaii 96701 A simple and universal platform for competitive

  16. Non-Standard Genetic Codes Define New Concepts for Protein Engineering.

    PubMed

    Bezerra, Ana R; Guimarães, Ana R; Santos, Manuel A S

    2015-01-01

    The essential feature of the genetic code is the strict one-to-one correspondence between codons and amino acids. The canonical code consists of three stop codons and 61 sense codons that encode 20% of the amino acid repertoire observed in nature. It was originally designated as immutable and universal due to its conservation in most organisms, but sequencing of genes from the human mitochondrial genomes revealed deviations in codon assignments. Since then, alternative codes have been reported in both nuclear and mitochondrial genomes and genetic code engineering has become an important research field. Here, we review the most recent concepts arising from the study of natural non-standard genetic codes with special emphasis on codon re-assignment strategies that are relevant to engineering genetic code in the laboratory. Recent tools for synthetic biology and current attempts to engineer new codes for incorporation of non-standard amino acids are also reviewed in this article. PMID:26569314

  17. DECOMPOSTION OF GENETICALLY ENGINEERED TOBACCO UNDER FIELD CONDITIONS: PERSISTENCE OF THE PROTEINASE INHIBITOR I PRODUCT AND EFFECTS OF SOIL MICROBIAL RESPIRATION AND PROTOZOA, NEMATODE AND MICROARTHR

    EPA Science Inventory

    1. To evaluate the potential effects of genetically engineered (transgenic) plants on soil ecosystems, litterbags containing leaves of non-engineered (parental) and transgenic tobacco plants were buried in field plots. The transgenic tobacco plants were genetically engineered to ...

  18. Genetic Engineering of Self-Assembled Protein Hydrogel Based on Elastin-like Sequences with Metal Binding Functionality

    E-print Network

    Chen, Wilfred

    Genetic Engineering of Self-Assembled Protein Hydrogel Based on Elastin-like Sequences with Metal genetic engineering.1,2 By preprogram- ming the coding information within a DNA template, precise control* Department of Chemical and Environmental Engineering, University of California, Riverside, California 92507

  19. Animal models of physiologic markers of male reproduction: genetically defined infertile mice

    SciTech Connect

    Chubb, C.

    1987-10-01

    The present report focuses on novel animal models of male infertility: genetically defined mice bearing single-gene mutations that induce infertility. The primary goal of the investigations was to identify the reproductive defects in these mutant mice. The phenotypic effects of the gene mutations were deciphered by comparing the mutant mice to their normal siblings. Initially testicular steroidogenesis and spermatogenesis were investigated. The physiologic markers for testicular steroidogenesis were steroid secretion by testes perifused in vitro, seminal vesicle weight, and Leydig cell histology. Spermatogenesis was evaluated by the enumeration of homogenization-resistant sperm/spermatids in testes and by morphometric analyses of germ cells in the seminiferous epithelium. If testicular function appeared normal, the authors investigated the sexual behavior of the mice. The parameters of male sexual behavior that were quantified included mount patency, mount frequency, intromission latency, thrusts per intromission, ejaculation latency, and ejaculation duration. Females of pairs breeding under normal circumstances were monitored for the presence of vaginal plugs and pregnancies. The patency of the ejaculatory process was determined by quantifying sperm in the female reproductive tract after sexual behavior tests. Sperm function was studied by quantitatively determining sperm motility during videomicroscopic observation. Also, the ability of epididymal sperm to function within the uterine environment was analyzed by determining sperm capacity to initiate pregnancy after artificial insemination. Together, the experimental results permitted the grouping of the gene mutations into three general categories. They propose that the same biological markers used in the reported studies can be implemented in the assessment of the impact that environmental toxins may have on male reproduction.

  20. Biotechnology, Genetic Engineering and Society. Monograph Series: III.

    ERIC Educational Resources Information Center

    Kieffer, George H.

    New techniques have expanded the field of biotechnology and awarded scientists an unprecedented degree of control over the genetic constitutions of living things. The knowledge of DNA science is the basis for this burgeoning industry which may be a major force in human existence. Just as it is possible to move genetic material from one organism to…

  1. N-acetylcysteineamide (NACA) prevents inflammation and oxidative stress in animals exposed to diesel engine exhaust.

    PubMed

    Banerjee, Atrayee; Trueblood, Max B; Zhang, Xinsheng; Manda, Kalyan Reddy; Lobo, Prem; Whitefield, Philip D; Hagen, Donald E; Ercal, Nuran

    2009-06-22

    Diesel exhaust particles (DEPs), a by-product of diesel engine exhaust (DEE), are one of the major components of air borne particulate matter (PM) in the urban environment. DEPs are composed of soot, polycyclic aromatic hydrocarbons (PAHs), redox active semi-quinones, and transition metals, which are known to produce pro-oxidative and pro-inflammatory effects, thereby leading to oxidative stress-induced damage in the lungs. The objective of this study was to determine if N-acetylcysteineamide (NACA), a novel thiol antioxidant, confers protection to animals exposed to DEPs from oxidative stress-induced damage to the lung. To study this, male C57BL/6 mice, pretreated with either NACA (250mg/kg body weight) or saline, were exposed to DEPs (15mg/m(3)) or filtered air (1.5-3h/day) for nine consecutive days. The animals were sacrificed 24h after the last exposure. NACA-treated animals exposed to DEP had significant decreases in the number of macrophages and the amount of mucus plug formation in the lungs, as compared to the DEP-only exposed animals. In addition, DEP-exposed animals, pretreated with NACA, also experienced significantly lower oxidative stress than the untreated group, as indicated by the glutathione (GSH), and malondialdehyde (MDA) levels and catalase (CAT) activity. Further, DEP-induced toxicity in the lungs was reversed in NACA-treated animals, as indicated by the lactate dehydrogenase levels. Taken together, these data suggest that the thiol-antioxidant, NACA, can protect the lungs from DEP-induced inflammation and oxidative stress related damage. PMID:19429263

  2. Dr. Campbell's Bio111 Exam #4 Fall 2001 Fall 2001 Biology 111 Exam #4 Genetic Engineering and Final Roundup

    E-print Network

    Campbell, A. Malcolm

    Dr. Campbell's Bio111 Exam #4 ­ Fall 2001 1 Fall 2001 Biology 111 Exam #4 ­ Genetic Engineering of genetic changes must be present in these genes in order for cancer to arise? 6 pts. 6) How does the long

  3. Physiology of SLC12 transporters: lessons from inherited human genetic mutations and genetically engineered mouse knockouts

    PubMed Central

    Gagnon, Kenneth B.

    2013-01-01

    Among the over 300 members of the solute carrier (SLC) group of integral plasma membrane transport proteins are the nine electroneutral cation-chloride cotransporters belonging to the SLC12 gene family. Seven of these transporters have been functionally described as coupling the electrically silent movement of chloride with sodium and/or potassium. Although in silico analysis has identified two additional SLC12 family members, no physiological role has been ascribed to the proteins encoded by either the SLC12A8 or the SLC12A9 genes. Evolutionary conservation of this gene family from protists to humans confirms their importance. A wealth of physiological, immunohistochemical, and biochemical studies have revealed a great deal of information regarding the importance of this gene family to human health and disease. The sequencing of the human genome has provided investigators with the capability to link several human diseases with mutations in the genes encoding these plasma membrane proteins. The availability of bacterial artificial chromosomes, recombination engineering techniques, and the mouse genome sequence has simplified the creation of targeting constructs to manipulate the expression/function of these cation-chloride cotransporters in the mouse in an attempt to recapitulate some of these human pathologies. This review will summarize the three human disorders that have been linked to the mutation/dysfunction of the Na-Cl, Na-K-2Cl, and K-Cl cotransporters (i.e., Bartter's, Gitleman's, and Andermann's syndromes), examine some additional pathologies arising from genetically modified mouse models of these cotransporters including deafness, blood pressure, hyperexcitability, and epithelial transport deficit phenotypes. PMID:23325410

  4. From microcarriers to hydrodynamics: introducing engineering science into animal cell culture.

    PubMed

    Croughan, Matthew S; Hu, Wei-Shou

    2006-10-01

    Professor Daniel I.C. Wang has conducted research in animal cell culture for approximately 40 years. Over that long time period and still to this day, he successfully addresses a multitude of engineering challenges, taking a unique, creative, systems-driven but still fundamental approach. As mammalian cell culture has become the predominant method of manufacturing therapeutic proteins, the impact of his leadership, not only in research but also student recruitment and education, has played a key role in the success of the bio/pharmaceutical industry. PMID:16933297

  5. The Information Value of Non-Genetic Inheritance in Plants and Animals

    PubMed Central

    English, Sinead; Pen, Ido; Shea, Nicholas; Uller, Tobias

    2015-01-01

    Parents influence the development of their offspring in many ways beyond the transmission of DNA. This includes transfer of epigenetic states, nutrients, antibodies and hormones, and behavioural interactions after birth. While the evolutionary consequences of such non-genetic inheritance are increasingly well understood, less is known about how inheritance mechanisms evolve. Here, we present a simple but versatile model to explore the adaptive evolution of non-genetic inheritance. Our model is based on a switch mechanism that produces alternative phenotypes in response to different inputs, including genes and non-genetic factors transmitted from parents and the environment experienced during development. This framework shows how genetic and non-genetic inheritance mechanisms and environmental conditions can act as cues by carrying correlational information about future selective conditions. Differential use of these cues is manifested as different degrees of genetic, parental or environmental morph determination. We use this framework to evaluate the conditions favouring non-genetic inheritance, as opposed to genetic determination of phenotype or within-generation plasticity, by applying it to two putative examples of adaptive non-genetic inheritance: maternal effects on seed germination in plants and transgenerational phase shift in desert locusts. Our simulation models show how the adaptive value of non-genetic inheritance depends on its mechanism, the pace of environmental change, and life history characteristics. PMID:25603120

  6. Monitoring for genetically engineered pseudomonas species in monterey county

    SciTech Connect

    Supkoff, D.; Opgenorth, D.; Lai, C.; Segawa, R.; Koehler, D.

    1987-01-01

    A field monitoring study was conducted to determine if genetically altered Pseudomonas fluorescens or P. syringae had been applied to sites in Monterey County. A series of diagnostic tests for antibiotic resistance, fluorescence ability, oxidase and arginine dihydrolase activities, hypersensitivity reaction and ice nucleation ability were conducted to screen bacteria isolated from field and control samples. No bacteria were detected from field samples which matched the expected test profiles of genetically altered bacterial products. In contrast, bacteria were consistently isolated from positive control samples with the expected characteristics of genetically altered bacteria.

  7. Genetic engineering: a matter that requires further refinement in Spanish secondary school textbooks

    NASA Astrophysics Data System (ADS)

    Martínez-Gracia, M. V.; Gil-Quýlez, M. J.

    2003-09-01

    Genetic engineering is now an integral part of many high school textbooks but little work has been done to assess whether it is being properly addressed. A checklist with 19 items was used to analyze how genetic engineering is presented in biology textbooks commonly used in Spanish high schools, including the content, its relationship with fundamental genetic principles, and how it aims to improve the genetic literacy of students. The results show that genetic engineering was normally introduced without a clear reference to the universal genetic code, protein expression or the genetic material shared by all species. In most cases it was poorly defined, without a clear explanation of all the relevant processes involved. Some procedures (such as vectors) were explained in detail without considering previous student knowledge or skills. Some books emphasized applications such as the human genome project without describing DNA sequencing. All books included possible repercussions, but in most cases only fashionable topics such as human cloning. There was an excess of information that was not always well founded and hence was unsuitable to provide a meaningful understanding of DNA technology required for citizens in the twenty-first century.

  8. Hybrid Neural-Network: Genetic Algorithm Technique for Aircraft Engine Performance Diagnostics Developed and Demonstrated

    NASA Technical Reports Server (NTRS)

    Kobayashi, Takahisa; Simon, Donald L.

    2002-01-01

    As part of the NASA Aviation Safety Program, a unique model-based diagnostics method that employs neural networks and genetic algorithms for aircraft engine performance diagnostics has been developed and demonstrated at the NASA Glenn Research Center against a nonlinear gas turbine engine model. Neural networks are applied to estimate the internal health condition of the engine, and genetic algorithms are used for sensor fault detection, isolation, and quantification. This hybrid architecture combines the excellent nonlinear estimation capabilities of neural networks with the capability to rank the likelihood of various faults given a specific sensor suite signature. The method requires a significantly smaller data training set than a neural network approach alone does, and it performs the combined engine health monitoring objectives of performance diagnostics and sensor fault detection and isolation in the presence of nominal and degraded engine health conditions.

  9. Vicariance and dispersal across an intermittent barrier: population genetic structure of marine animals across the Torres Strait land bridge

    NASA Astrophysics Data System (ADS)

    Mirams, A. G. K.; Treml, E. A.; Shields, J. L.; Liggins, L.; Riginos, C.

    2011-12-01

    Biogeographic barriers, some transitory in duration, are likely to have been important contributing factors to modern marine biodiversity in the Indo-Pacific region. One such barrier was the Torres Strait land bridge between continental Australia and New Guinea that persisted through much of the late Pleistocene and separated Indian and Pacific Ocean taxa. Here, we examine the patterns of mitochondrial DNA diversity for marine animals with present-day distributions spanning the Torres Strait. Specifically, we investigate whether there are concordant signatures across species, consistent with either vicariance or recent colonization from either ocean basin. We survey four species of reef fishes ( Apogon doederleini, Pomacentrus coelestis, Dascyllus trimaculatus, and Acanthurus triostegus) for mtDNA cytochrome oxidase 1 and control region variation and contrast these results to previous mtDNA studies in diverse marine animals with similar distributions. We find substantial genetic partitioning (estimated from F-statistics and coalescent approaches) between Indian and Pacific Ocean populations for many species, consistent with regional persistence through the late Pleistocene in both ocean basins. The species-specific estimates of genetic divergence, however, vary greatly and for reef fishes we estimate substantially different divergence times among species. It is likely that Indian and Pacific Ocean populations have been isolated for multiple glacial cycles for some species, whereas for other species genetic connections have been more recent. Regional estimates of genetic diversity and directionality of gene flow also vary among species. Thus, there is no apparent consistency among historical patterns across the Torres Strait for these co-distributed marine animals.

  10. On-chip whole-animal manipulation for high-throughput subcellular-resolution in-vivo drug/genetic screening

    E-print Network

    Yanik, Mehmet Fatih

    Techniques for rapid and automated small-animal manipulation and immobilization are necessary for high-throughput in vivo genetic/drug screens using cellular and sub-cellular features in multicellular organisms. We present ...

  11. Non-Genetic Engineering Approaches for Isolating and Generating Novel Yeasts for Industrial Applications

    NASA Astrophysics Data System (ADS)

    Chambers, P. J.; Bellon, J. R.; Schmidt, S. A.; Varela, C.; Pretorius, I. S.

    Generating novel yeast strains for industrial applications should be quite straightforward; after all, research into the genetics, biochemistry and physiology of Baker's Yeast, Saccharomyces cerevisiae, has paved the way for many advances in the modern biological sciences. We probably know more about this humble eukaryote than any other, and it is the most tractable of organisms for manipulation using modern genetic engineering approaches. In many countries, however, there are restrictions on the use of genetically-modified organisms (GMOs), particularly in foods and beverages, and the level of consumer acceptance of GMOs is, at best, variable. Thus, many researchers working with industrial yeasts use genetic engineering techniques primarily as research tools, and strain development continues to rely on non-GM technologies. This chapter explores the non-GM tools and strategies available to such researchers.

  12. Review of aerospace engineering cost modelling: The genetic causal approach

    NASA Astrophysics Data System (ADS)

    Curran, R.; Raghunathan, S.; Price, M.

    2004-11-01

    The primary intention of this paper is to review the current state of the art in engineering cost modelling as applied to aerospace. This is a topic of current interest and in addressing the literature, the presented work also sets out some of the recognised definitions of cost that relate to the engineering domain. The paper does not attempt to address the higher-level financial sector but rather focuses on the costing issues directly relevant to the engineering process, primarily those of design and manufacture. This is of more contemporary interest as there is now a shift towards the analysis of the influence of cost, as defined in more engineering related terms; in an attempt to link into integrated product and process development (IPPD) within a concurrent engineering environment. Consequently, the cost definitions are reviewed in the context of the nature of cost as applicable to the engineering process stages: from bidding through to design, to manufacture, to procurement and ultimately, to operation. The linkage and integration of design and manufacture is addressed in some detail. This leads naturally to the concept of engineers influencing and controlling cost within their own domain rather than trusting this to financers who have little control over the cause of cost. In terms of influence, the engineer creates the potential for cost and in a concurrent environment this requires models that integrate cost into the decision making process.

  13. A Hybrid Neural Network-Genetic Algorithm Technique for Aircraft Engine Performance Diagnostics

    NASA Technical Reports Server (NTRS)

    Kobayashi, Takahisa; Simon, Donald L.

    2001-01-01

    In this paper, a model-based diagnostic method, which utilizes Neural Networks and Genetic Algorithms, is investigated. Neural networks are applied to estimate the engine internal health, and Genetic Algorithms are applied for sensor bias detection and estimation. This hybrid approach takes advantage of the nonlinear estimation capability provided by neural networks while improving the robustness to measurement uncertainty through the application of Genetic Algorithms. The hybrid diagnostic technique also has the ability to rank multiple potential solutions for a given set of anomalous sensor measurements in order to reduce false alarms and missed detections. The performance of the hybrid diagnostic technique is evaluated through some case studies derived from a turbofan engine simulation. The results show this approach is promising for reliable diagnostics of aircraft engines.

  14. Standardization of functional reporter and antibiotic resistance cassettes to facilitate the genetic engineering of filamentous fungi.

    PubMed

    Sureka, Swati; Chakravorty, Arun; Holmes, Eric C; Spassibojko, Olga; Bhatt, Nupur; Wu, Dongliang; Turgeon, B Gillian

    2014-12-19

    The unique physiological properties of fungi are useful for a myriad of applications, which could greatly benefit from increased control of native pathways and introduction of recombinant genes. However, fungal genetic engineering is still limited in scope and accessibility, largely due to lack of standardization. To help standardize the genetic engineering of filamentous fungi, we created BioBricks of commonly used antibiotic resistance genes, neomycin phosphotransferase (nptII) and hygromycin phosphotransferase (hph), which confer resistance to G418 (Geneticin) and hygromycin B, respectively. Additionally, we created a BioBrick of the constitutive trpC promoter, from the tryptophan biosynthesis pathway of Aspergillus nidulans, and used it to create a composite part including the GFP gene. The functionality of these parts was demonstrated in the model fungal organism Cochliobolus heterostrophus, and as these tools are in modular BioBrick format, they can be easily used to facilitate genetic engineering of other fungal species. PMID:25524098

  15. (Co)variance components and genetic parameters for growth traits in Arabi sheep using different animal models.

    PubMed

    Shokrollahi, B; Baneh, H

    2012-01-01

    The objective of the present study was to estimate genetic parameters for body weight at different ages in Arabi sheep using data collected from 1999 to 2009. Investigated traits consisted of birth weight (N = 2776), weaning weight (N = 2002) and weight at six months of age (N = 1885). The data were analyzed using restricted maximum likelihood analysis, by fitting univariate and multivariate animal models. All three weight traits were significantly influenced by birth year, sex and birth type. Age of dam only significantly affected birth weight. Log-likelihood ratio tests were conducted to determine the most suitable model for each growth trait in univariate analyses. Direct and total heritability estimates for birth weight, weaning weight and weight at six months of age (based on the best model) were 0.42 and 0.16 (model 4), 0.38 and 0.13 (model 4) and 0.14 and 0.14 (model 1), respectively. Estimation of maternal heritability for birth weight and weaning weight was 0.22 and 0.18, respectively. Genetic and phenotypic correlations among these traits were positive. Phenotypic correlations among traits were low to moderate. Genetic correlations among traits were positive and higher than the corresponding phenotypic correlations. Weaning weight had a strong and significant correlation with weight at six months of age (0.99). We conclude that selection can be made in animals based on weaning weight instead of the present practice of selection based on weight at six months. PMID:22370932

  16. Genetic diversity of laboratory gray short-tailed opossums (Monodelphis domestica): effect of newly introduced wild-caught animals.

    PubMed

    van Oorschot, R A; Williams-Blangero, S; VandeBerg, J L

    1992-06-01

    The colony of gray, short-tailed opossums (Monodelphis domestica) at the Southwest Foundation for Biomedical Research, the primary supplier of this species for research purposes, was founded with nine animals trapped in 1978 in the state of Pernambuco, Brazil. Since 1984, 14 newly acquired founders from the state of Paraiba, Brazil have contributed to the gene pool of the colony. The animals from Paraiba and their descendants are significantly larger than the founders from Pernambuco and their descendants. The two groups also differ significantly in several measurements of morphologic traits. The changes in proportional contribution of each founder to the colony, and changes in inbreeding coefficients during the colony's history, are evaluated. Using previously established markers and three newly identified markers (ACP2, APRT, and DIA1), we show that the Paraiba-derived animals differ significantly from the original founders in allele frequencies and heterozygosity. The genetic diversity of the colony has been substantially increased by acquisition of the new founders from Paraiba. The colony is highly polymorphic, with 22.2% of loci surveyed by protein electrophoresis being variable. We conclude that the genetic differences between populations and among projects within the colony should be considered in future colony management procedures and in selection of experimental subjects. PMID:1320155

  17. Genetic Manipulation in Pigs

    PubMed Central

    Sachs, David H.; Galli, Cesare

    2009-01-01

    Purpose of Review Recent developments in the field of genetic engineering have made it possible to add, delete or exchange genes from one species to another. This technology has special relevance to the field of xenotransplantation, in which the elimination of a species-specific disparity could make the difference between success or failure of an organ transplant. This review focuses on developments in both the techniques and applications of genetically modified animals. Recent Findings Advances have been made using existing techniques for genetic modifications of swine and in the development of new, emerging technologies, including enzymatic engineering and the use of siRNA. Applications of the modified animals have provided evidence that genetically modified swine have the potential to overcome both physiologic and immunologic barriers that have previously impeded this field. Use of GalT-KO animals as donors have shown marked improvements in xenograft survivals. Summary Techniques for genetic engineering of swine have been directed toward avoiding naturally existing cellular and antibody responses to species-specific antigens. Organs from genetically engineered animals have enjoyed markedly improved survivals in non-human primates, especially in protocols directed toward the induction of tolerance, presumably by avoiding immunization to new antigens. PMID:19469029

  18. New method for preparing more stable microcapsules for the entrapment of genetically engineered cells.

    PubMed

    Wang, Man-Yan; Yu, Yao-Ting; Chang, T M S

    2005-01-01

    In this paper, we studied a new preparation method of microcapsules for entrapment of genetically engineered cells. Polyvinyl alcohol microcapsules having well defined shape, high mechanical strength, good biochemical and permeability properties were prepared by using low temperature physical cross-linking method. Comparing with currently used alginate-polylysine-alginate microcapsules, polyvinyl alcohol microcapsules have much higher mechanical strength. The low temperature physical crosslinking procedure of polyvinyl alcohol is nontoxic to the genetically engineered E. coli DH5alpha cell, which attained high activity in decomposing and metabolizing urea in vitro studies. PMID:16152691

  19. Genetic engineering of human ES and iPS cells using TALE nucleases

    PubMed Central

    Hockemeyer, Dirk; Wang, Haoyi; Kiani, Samira; Lai, Christine S; Gao, Qing; Cassady, John P; Cost, Gregory J; Zhang, Lei; Santiago, Yolanda; Miller, Jeffrey C; Zeitler, Bryan; Cherone, Jennifer M; Meng, Xiangdong; Hinkley, Sarah J; Rebar, Edward J; Gregory, Philip D; Urnov, Fyodor D; Jaenisch, Rudolf

    2011-01-01

    Targeted genetic engineering of human pluripotent cells is a prerequisite for exploiting their full potential. Such genetic manipulations can be achieved using site-specific nucleases. Here, we engineered Transcription Activation-Like Effector Nucleases (TALENs) for five distinct genomic loci. At all loci tested we obtained hESC and iPSC single-cell-derived clones carrying transgenic cassettes solely at the TALEN-specified location. Thus, TALENs mediate site-specific genome modifications in human pluripotent cells with comparable efficiency and precision as zinc finger nucleases (ZFNs). PMID:21738127

  20. Cellular computation and communications using engineered genetic regulatory networks

    E-print Network

    Weiss, Ron, 1970-

    2001-01-01

    In this thesis, I present an engineering discipline for obtaining complex, predictable, and reliable cell behaviors by embedding biochemical logic circuits and programmed intercellular communications into cells. To accomplish ...

  1. Using HexSim to link demography and genetics in animal and plant simulations

    EPA Science Inventory

    Simulation models are essential for understanding the effects of land management practices and environmental drivers, including landscape change, shape population genetic structure and persistence probabilities. The emerging field of eco-evolutionary modeling is beginning to dev...

  2. Adenosine deaminase-deficient mice generated using a two-stage genetic engineering strategy exhibit a combined immunodeficiency.

    PubMed

    Blackburn, M R; Datta, S K; Kellems, R E

    1998-02-27

    Adenosine deaminase (ADA) deficiency in humans leads to a combined immunodeficiency. The mechanisms involved in the lymphoid specificity of the disease are not fully understood due to the inaccessibility of human tissues for detailed analysis and the absence of an adequate animal model for the disease. We report the use of a two-stage genetic engineering strategy to generate ADA-deficient mice that retain many features associated with ADA deficiency in humans, including a combined immunodeficiency. Severe T and B cell lymphopenia was accompanied by a pronounced accumulation of 2'-deoxyadenosine and dATP in the thymus and spleen, and a marked inhibition of S-adenosylhomocysteine hydrolase in these organs. Accumulation of adenosine was widespread among all tissues examined. ADA-deficient mice also exhibited severe pulmonary insufficiency, bone abnormalities, and kidney pathogenesis. These mice have provided in vivo information into the metabolic basis for the immune phenotype associated with ADA deficiency. PMID:9478961

  3. 76 FR 63278 - Bayer CropScience LP; Determination of Nonregulated Status for Cotton Genetically Engineered for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-12

    ... Through Genetic Engineering Which Are Plant Pests or Which There Is Reason to Believe Are Plant Pests... environment) of organisms and products altered or produced through genetic engineering that are plant pests or... notice\\1\\ published in the Federal Register on June 28, 2011 (76 FR 37769-37770, Docket No....

  4. Engineering Applications of Artificial Intelligence 14 (2001) 114 Genetic adaptive control for an inverted wedge: experiments and

    E-print Network

    2001-01-01

    Engineering Applications of Artificial Intelligence 14 (2001) 1­14 Genetic adaptive control. Passino* Department of Electrical Engineering, The Ohio State University, 2015 Neil Avenue, Columbus, OH and real-time implementation issues will be discussed and the genetic adaptive strategy will be compared

  5. 78 FR 51706 - Bayer CropScience LP; Determination of Nonregulated Status of Soybean Genetically Engineered for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-21

    ... part 340, ``Introduction of Organisms and Products Altered or Produced Through Genetic Engineering... and products altered or produced through genetic engineering that are plant pests or that there is...' regulations in 7 CFR part 340. In a notice \\1\\ published in the Federal Register on July 13, 2012 (77 FR...

  6. SURVIVAL AND ENUMERATION OF AEROSOLIZED AND FREEZE-DRIED GENETICALLY ENGINEERED E. COLI, UNDER CONTROLLED ENVIRONMENTAL CONDITIONS

    EPA Science Inventory

    Aerosol survival of a genetically engineered strain of Escherichia coli demonstrated a more rapid die-off (i.e., death rate) compared to its parental wildtype. p to 77% of a freeze-dried and air-exposed genetically engineered microorganism (GEM) and wildtype bacteria could be res...

  7. Turk J Elec Engin, VOL.9, NO.1 2001, c TUBITAK Meta-Genetic Programming: Co-evolving the

    E-print Network

    Fernandez, Thomas

    Turk J Elec Engin, VOL.9, NO.1 2001, c T¨UBITAK Meta-Genetic Programming: Co-evolving the Operators, Aytoun Street, Manchester, M1 3GH-UK Abstract The standard Genetic Programming approach is augmented by co-evolving the genetic operators. To do this the operators are coded as trees of indefinite length

  8. Gene therapy in dentistry: tool of genetic engineering. Revisited.

    PubMed

    Gupta, Khushboo; Singh, Saurabh; Garg, Kavita Nitish

    2015-03-01

    Advances in biotechnology have brought gene therapy to the forefront of medical research. The concept of transferring genes to tissues for clinical applications has been discussed nearly half a century, but the ability to manipulate genetic material via recombinant DNA technology has brought this goal to reality. The feasibility of gene transfer was first demonstrated using tumour viruses. This led to development of viral and nonviral methods for the genetic modification of somatic cells. Applications of gene therapy to dental and oral problems illustrate the potential impact of this technology on dentistry. Preclinical trial results regarding the same have been very promising. In this review we will discuss methods, vectors involved, clinical implication in dentistry and scientific issues associated with gene therapy. PMID:25540850

  9. An Ethical Study on the Uses of Enhancement Genetic Engineering

    NASA Astrophysics Data System (ADS)

    Kawakita, Koji

    A variety of biomedical technologies are being developed that can be used for purposes other than treating diseases. Such “enhancement technologies” can be used to improve our own and future generation's life-chances. While these technologies can help people in many ways, their use raises important ethical issues. Some arguments for anti-enhancement as well as pro-enhancement seem to rest, however, on shaky foundation. Both company engineers and the general public had better learn more from technological, economical and philosophical histories. For such subjects may provide engineers with less opportunities of technological misuses and more powers of self-esteem in addition to self-control.

  10. The significance of content knowledge for informal reasoning regarding socioscientific issues: Applying genetics knowledge to genetic engineering issues

    NASA Astrophysics Data System (ADS)

    Sadler, Troy D.; Zeidler, Dana L.

    2005-01-01

    This study focused on informal reasoning regarding socioscientific issues. It sought to explore how content knowledge influenced the negotiation and resolution of contentious and complex scenarios based on genetic engineering. Two hundred and sixty-nine students drawn from undergraduate natural science and nonnatural science courses completed a quantitative test of genetics concepts. Two subsets (n = 15 for each group) of the original sample representing divergent levels of content knowledge participated in individual interviews, during which they articulated positions, rationales, counterpositions, and rebuttals in response to three gene therapy scenarios and three cloning scenarios. A mixed-methods approach was used to examine the effects of content knowledge on the use of informal reasoning patterns and the quality of informal reasoning. Participants from both groups employed the same general patterns of informal reasoning. Data did indicate that differences in content knowledge were related to variations in informal reasoning quality. Participants, with more advanced understandings of genetics, demonstrated fewer instances of reasoning flaws, as defined by a priori criteria, and were more likely to incorporate content knowledge in their reasoning patterns than participants with more naïve understandings of genetics. Implications for instruction and future research are discussed.

  11. MICROCOSM FOR MEASURING SURVIVAL AND CONJUGATION OF GENETICALLY ENGINEERED BACTERIA IN RHIZOSPHERE ENVIRONMENTS

    EPA Science Inventory

    A microcosm is described to evaluate and measure bacterial conjugation in the rhizosphere of barley and radish with strains of Pseudomonas cepacia. he purpose was to describe a standard method useful for evaluating the propensity of genetically engineered microorganisms (GEMs) to...

  12. Engineering a genetic transformation system for Colletotrichum acutatum, the causal fungus of lime anthracnose

    E-print Network

    Burns, Jacqueline K.

    Engineering a genetic transformation system for Colletotrichum acutatum, the causal fungus of lime loss on most citrus cultivars. Isolates from Key lime anthracnose (KLA) cause that disease on the Mexican lime, but also cause PFD on sweet orange. Both PFD and KLA isolates exhibited resistance

  13. 'HoneySweet' plum - a valuable genetically engineered fruit-tree cultivar and germplasm resource

    Technology Transfer Automated Retrieval System (TEKTRAN)

    ‘HoneySweet’ is a plum variety developed through genetic engineering to be highly resistant to plum pox potyvirus (PPV), the causal agent of sharka disease, that threatens stone-fruit industries world-wide and most specifically, in Europe. Field testing for over 15 years in Europe has demonstrated ...

  14. Development of enzymes and enzyme systems by genetic engineering to convert biomass to sugars

    Technology Transfer Automated Retrieval System (TEKTRAN)

    TITLE Development of Enzymes and Enzyme Systems by Genetic Engineering to Convert Biomass to Sugars ABSTRACT Plant cellulosic material is one of the most viable renewable resources for the world’s fuel and chemical feedstock needs. Currently ethanol derived from corn starch is the most common li...

  15. Reactions to a New Technology: Students' Ideas about Genetically Engineered Foodstuffs.

    ERIC Educational Resources Information Center

    Hill, Ruaraidh; Stanisstreet, Martin; Boyes, Edward; O'Sullivan, Helen

    1998-01-01

    Explores the prevalence of ideas among 16 to 19 year-old students about the application of the rapidly expanding technology of genetic engineering to food production. Findings suggest that more females were cautious about these foodstuffs than were males. Contains 20 references. (DDR)

  16. IMPROVING PLANT GENETIC ENGINEERING BY MANIPULATING THE HOST. (R829479C001)

    EPA Science Inventory

    Agrobacterium-mediated transformation is a major technique for the genetic engineering of plants. However, there are many economically important crop and tree species that remain highly recalcitrant to Agrobacterium infection. Although attempts have been made to ...

  17. 76 FR 63279 - Monsanto Co.; Determination of Nonregulated Status for Soybean Genetically Engineered for Insect...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-12

    ... Products Altered or Produced Through Genetic Engineering Which Are Plant Pests or Which There Is Reason to... notice\\1\\ published in the Federal Register on June 28, 2011 (76 FR 37770-37771, Docket No. APHIS-2011... movement, or release into the environment) of organisms and products altered or produced through...

  18. Enhancing the Internationalisation of Distance Education in the Biological Sciences: The DUNE Project and Genetic Engineering.

    ERIC Educational Resources Information Center

    Leach, C. K.; And Others

    1997-01-01

    Describes the Distance Educational Network of Europe (DUNE) project that aims at enhancing the development of distance education in an international context. Highlights issues relating to the delivery of distance-learning courses in a transnational forum. Describes the genetic engineering course that aims at explaining the core techniques of…

  19. 76 FR 80869 - Monsanto Co.; Determination of Nonregulated Status of Corn Genetically Engineered for Drought...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-27

    ... Products Altered or Produced Through Genetic Engineering Which Are Plant Pests or Which There Is Reason to...\\ published in the Federal Register on May 11, 2011 (76 FR 27303-27304, Docket No. APHIS-2011-0023), APHIS..., 2011. On July 27, 2011, APHIS published in the Federal Register (76 FR 44891-44892, Docket No....

  20. 78 FR 66891 - Monsanto Co.; Determination of Nonregulated Status of Soybean Genetically Engineered for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-07

    ... and products altered or produced through genetic engineering that are plant pests or that there is.... In a notice \\2\\ published in the Federal Register on July 13, 2012, (77 FR 41354-41355, Docket No... (77 FR 13258-13260, Docket No. APHIS-2011-0129) a notice describing our public review process...

  1. METHODS TO MEASURE THE INFLUENCE OF GENETICALLY ENGINEERED BACTERIA ON ECOLOGICAL PROCESSES IN SOIL

    EPA Science Inventory

    The purpose of this document is to summarize the methods and concep s that have been developed and used by the author and his colleagues to study the potential effects of genetically engineered microorganisms (GEMs) introduced, deliberately or accidently, into soil on microbemedi...

  2. Challenges to IPM Advancement: Pesticides, Biocontrol, Genetic Engineering, and Invasive Species.

    E-print Network

    Hoddle, Mark S.

    77 Challenges to IPM Advancement: Pesticides, Biocontrol, Genetic Engineering, and Invasive Species management issues related to pesticide use, importation and utilization of exotic natural enemies, deployment(IPM)haditsgenesisin the mid to late 1950's when the detrimental effects of pesticide overuse became increasingly apparent

  3. Rapid engineering of versatile molecular logic gates using heterologous genetic transcriptional modules.

    PubMed

    Wang, Baojun; Buck, Martin

    2014-10-11

    We designed and constructed versatile modular genetic logic gates in bacterial cells. These function as digital logic 1-input Buffer gate, 2-input and 3-input AND gates with one inverted input and integrate multiple chemical input signals in customised logic manners. Such rapidly engineered devices serve to achieve increased sensing signal selectivity. PMID:25062273

  4. SURVIVAL OF GENETICALLY ENGINEERED MICROBES IN THE ENVIRONMENT: EFFECT OF HOST/VECTOR RELATIONSHIP

    EPA Science Inventory

    The fate and survival of genetically engineered microbes is dependent on the survival, establishment, and growth of the microbial host, as well as on the maintenance, replication, and segregation of the recombinant plasmids within the bacterial host population. The interactions o...

  5. Genetically encoded biosensors based on engineered fluorescent proteins Wolf B. Frommer, Michael W. Davidson, Robert Campbell

    E-print Network

    Campbell, Robert E.

    ,73 For imaging of protein activation and conformational changes Rho family GTPase activation Raichu-Ras, -Rap1Genetically encoded biosensors based on engineered fluorescent proteins Wolf B. Frommer, Michael W of metabolites various amino acids FLIP series; Arg sensor; GluSnFR 46,48-50 Protein kinase A ART; AKAR1-3 51

  6. Can Man Control His Biological Evolution? A Symposium on Genetic Engineering. Probabilities and Practicalities

    ERIC Educational Resources Information Center

    Djerassi, Carl

    1972-01-01

    Manipulation of genes in human beings on a large scale is not possible under present conditions because it lacks economic potential and other attractions for industry. However, preventive'' genetic engineering may be a field for vast research in the future and will perhaps be approved by governments, parishes, people and industry. (PS)

  7. Genetic Engineering of Mesenchymal Stem Cells and Its Application in Human Disease Therapy

    PubMed Central

    Hodgkinson, Conrad P.; Gomez, José A.; Mirotsou, Maria

    2010-01-01

    Abstract The use of stem cells for tissue regeneration and repair is advancing both at the bench and bedside. Stem cells isolated from bone marrow are currently being tested for their therapeutic potential in a variety of clinical conditions including cardiovascular injury, kidney failure, cancer, and neurological and bone disorders. Despite the advantages, stem cell therapy is still limited by low survival, engraftment, and homing to damage area as well as inefficiencies in differentiating into fully functional tissues. Genetic engineering of mesenchymal stem cells is being explored as a means to circumvent some of these problems. This review presents the current understanding of the use of genetically engineered mesenchymal stem cells in human disease therapy with emphasis on genetic modifications aimed to improve survival, homing, angiogenesis, and heart function after myocardial infarction. Advancements in other disease areas are also discussed. PMID:20825283

  8. A Candida albicans CRISPR system permits genetic engineering of essential genes and gene families

    PubMed Central

    Vyas, Valmik K.; Barrasa, M. Inmaculada; Fink, Gerald R.

    2015-01-01

    Candida albicans is a pathogenic yeast that causes mucosal and systematic infections with high mortality. The absence of facile molecular genetics has been a major impediment to analysis of pathogenesis. The lack of meiosis coupled with the absence of plasmids makes genetic engineering cumbersome, especially for essential functions and gene families. We describe a C. albicans CRISPR system that overcomes many of the obstacles to genetic engineering in this organism. The high frequency with which CRISPR-induced mutations can be directed to target genes enables easy isolation of homozygous gene knockouts, even without selection. Moreover, the system permits the creation of strains with mutations in multiple genes, gene families, and genes that encode essential functions. This CRISPR system is also effective in a fresh clinical isolate of undetermined ploidy. Our method transforms the ability to manipulate the genome of Candida and provides a new window into the biology of this pathogen. PMID:25977940

  9. On Natural Genetic Engineering: Structural Dynamism in Random Boolean Networks

    E-print Network

    Bull, Larry

    2012-01-01

    This short paper presents an abstract, tunable model of genomic structural change within the cell lifecycle and explores its use with simulated evolution. A well-known Boolean model of genetic regulatory networks is extended to include changes in node connectivity based upon the current cell state, e.g., via transposable elements. The underlying behaviour of the resulting dynamical networks is investigated before their evolvability is explored using a version of the NK model of fitness landscapes. Structural dynamism is found to be selected for in non-stationary environments and subsequently shown capable of providing a mechanism for evolutionary innovation when such reorganizations are inherited.

  10. SURVIVAL OF, AND GENETIC TRANSFER BY, GENETICALLY ENGINEERED BACTERIA IN NATURAL ENVIRONMENTS

    EPA Science Inventory

    The article reviews the few studies that have evaluated the survival of bacterial hosts and cloning vectors (e.g., phages) and the transfer of genetic information, by the processes of conjugation, transduction, and transformation, in aquatic and terrestrial environments and on pl...

  11. Genetic engineering of somatic cells to study and improve cardiac function

    PubMed Central

    Kirkton, Robert D.; Bursac, Nenad

    2012-01-01

    Aims To demonstrate the utility of genetically engineered excitable cells for studies of basic electrophysiology and cardiac cell therapy. Methods and results ‘Zig-zag’ networks of neonatal rat ventricular myocytes (NRVMs) were micropatterned onto thin elastomeric films to mimic the slow action potential (AP) conduction found in fibrotic myocardium. Addition of genetically engineered excitable human embryonic kidney cells (HEK-293 cells) (‘Ex-293’ cells stably expressing Kir2.1, Nav1.5, and Cx43 channels) increased both cardiac conduction velocity by 370% and twitch force amplitude by 64%. Furthermore, we stably expressed mutant Nav1.5 [A1924T (fast sodium channel mutant (substitution of alanine by threonine at amino acid 1924)] channels with hyperpolarized steady-state activation and showed that, despite a 71.6% reduction in peak INa, these cells propagated APs at the same velocity as the wild-type Nav1.5-expressing Ex-293 cells. Stable expression of Cav3.3 (T-type voltage-gated calcium) channels in Ex-293 cells (to generate an ‘ExCa-293’ line) significantly increased their AP duration and reduced repolarization gradients in cocultures of these cells and NRVMs. Additional expression of an optogenetic construct [ChIEF (light-gated Channelrhodopsin mutant)]enabled light-based control of AP firing in ExCa-293 cells. Conclusion We show that, despite being non-contractile, genetically engineered excitable cells can significantly improve both electrical and mechanical function of engineered cardiac tissues in vitro. We further demonstrate the utility of engineered cells for tissue-level studies of basic electrophysiology and cardiac channelopathies. In the future, this novel platform could be utilized in the high-throughput design of new genetically encoded indicators of cell electrical function, validation, and improvement of computer models of AP conduction, and development of novel engineered somatic cell therapies for the treatment of cardiac infarction and arrhythmias. PMID:23104914

  12. Risk Analysis, Vol. 26, No. 3, 2006 DOI: 10.1111/j.1539-6924.2006.00763.x Genetically Engineered Plants, Endangered Species,

    E-print Network

    Peterson, Robert K. D.

    Risk Analysis, Vol. 26, No. 3, 2006 DOI: 10.1111/j.1539-6924.2006.00763.x Genetically Engineered,3 and Paula M. Davis4 Genetically engineered maize (Zea mays) containing insecticidal endotoxin-of-ways, and managed forest lands (Swengel, 1995). Genetically engineered maize (Zea mays L.) con- taining insecticidal

  13. U.S. SWINE GENETIC RESOURCES AND THE NATIONAL ANIMAL GERMPLASM PROGRAM

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The National Animal Germplasm Program (NAGP) has begun to develop cryopreserved germplasm collection for all U.S. swine breeds. In developing these collections the inbreeding trends for pig breeds have been computed. As of 2004, average breed inbreeding levels ranged between 5% and 6% for Duroc, Yor...

  14. Revealing gene function and genetic diversity in plants and animals via TILLING and EcoTILLING

    Technology Transfer Automated Retrieval System (TEKTRAN)

    With the fairly recent advent of inexpensive, rapid sequencing technologies that continues to improve sequencing efficiency and accuracy, many species of animals, plants, and microbes have complete annotated genome information publicly available. The focus on genomics has thus been shifting from th...

  15. Genetically Engineered Poxviruses for Recombinant Gene Expression, Vaccination, and Safety

    NASA Astrophysics Data System (ADS)

    Moss, Bernard

    1996-10-01

    Vaccinia virus, no longer required for immunization against smallpox, now serves as a unique vector for expressing genes within the cytoplasm of mammalian cells. As a research tool, recombinant vaccinia viruses are used to synthesize and analyze the structure--function relationships of proteins, determine the targets of humoral and cell-mediated immunity, and investigate the types of immune response needed for protection against specific infectious diseases and cancer. The vaccine potential of recombinant vaccinia virus has been realized in the form of an effective oral wild-life rabies vaccine, although no product for humans has been licensed. A genetically altered vaccinia virus that is unable to replicate in mammalian cells and produces diminished cytopathic effects retains the capacity for high-level gene expression and immunogenicity while promising exceptional safety for laboratory workers and potential vaccine recipients.

  16. Knowledge-based engineering for mould design based on the use of genetic algorithm

    NASA Astrophysics Data System (ADS)

    Jiang, Peng; Hu, Jianjun; Xu, Hongbin

    2005-12-01

    The process of mould design depends on one's engineering knowledge and design experience. Knowledge-based engineering (KBE) adequately utilizes such knowledge and experience to design. KBE is a very important approach for increasing the intelligence and speed-up of the time of engineering design. In recent years, the use of genetic algorithms, as an optimization method, enables a rapid development. It searches the optimum solution for a problem using the principle of "survival of the fittest". In the process of mould design, constraint conditions for important parameters are set up. Then, a genetic algorithm is used to code these parameters and search for the optimum (or approximate optimum) solution of these parameters. Compared with general KBE, the KBE based on a genetic algorithm enhances the efficiency of design and the precision of solution. It not only makes use of the knowledge and experience of experts and designers, but also utilizes the great ability and generality of genetic algorithms in searching for an optimum solution.

  17. Environmental and genetic factors affecting the response of laboratory animals to drugs.

    PubMed

    Vesell, E S; Lang, C M; White, W J; Passananti, G T; Hill, R N; Clemens, T L; Liu, D K; Johnson, W D

    1976-04-01

    Only some of the diverse factors that can affect drug disposition and response in laboratory animals have been identified at the present time. These numerous factors contribute to large day-to-day variations that have become a major problem impeding investigation of drug disposition and response in laboratory animals. Although these variations render many experiments difficult to interpret and produce large discrepancies in the literature, few published investigations using laboratory animals provide sufficient details to permit replication of the studies under similar conditions with respect to these variables. Thus, the importance of these variables in affecting results is apparently insufficiently recognized at present. Two commonly overlooked variables affecting the activity of hepatic microsomal enzymes (HME) in rodents and hence the rate at which rodents eliminate from their bodies many foreign compounds are the bedding under the wire mesh cage and the relative cleanliness of the environment. Numerous chemicals present in relatively low concentrations in the environment of the animal room can significantly alter HME activity. Representative of these chemicals are aromatic hydrocarbons in cedarwood bedding, eucalyptol from aerosol sprays, and chlorinated hydrocarbon insecticides, each of which induces HME activity, whereas ammonia generated from feces and urine accumulated in unchanged pans under cages may inhibit HME activity. Chloroform, identified as an environmental contaminant of the water and air of certain cities, exhibits sex and strain differences with respect to toxicity (LD50) in mice. After intraperitoneal injection, twice as much chloroform accumulated in the kidneys of males from the sensitive strain (DBA/2J) as from the resistant (C57BL/6J) strain. First generation offspring were midway between parental strains both with respect to LD50 and renal accumulation of chloroform. PMID:1261707

  18. Exploration of the Hypothalamic-Pituitary-Adrenal Axis to Improve Animal Welfare by Means of Genetic Selection: Lessons from the South African Merino

    PubMed Central

    Hough, Denise; Swart, Pieter; Cloete, Schalk

    2013-01-01

    Simple Summary Breeding sheep that are robust and easily managed may be beneficial for both animal welfare and production. Sheep that are more readily able to adapt to stressful situations and a wide variety of environmental conditions are likely to have more resources available for a higher expression of their production potential. This review explores the utilization of one of the stress response pathways, namely the hypothalamic-pituitary-adrenal axis, to locate potential sites where genetic markers might be identified that contribute to sheep robustness. A South African Merino breeding programme is used to demonstrate the potential benefits of this approach. Abstract It is a difficult task to improve animal production by means of genetic selection, if the environment does not allow full expression of the animal’s genetic potential. This concept may well be the future for animal welfare, because it highlights the need to incorporate traits related to production and robustness, simultaneously, to reach sustainable breeding goals. This review explores the identification of potential genetic markers for robustness within the hypothalamic-pituitary-adrenal axis (HPAA), since this axis plays a vital role in the stress response. If genetic selection for superior HPAA responses to stress is possible, then it ought to be possible to breed robust and easily managed genotypes that might be able to adapt to a wide range of environmental conditions whilst expressing a high production potential. This approach is explored in this review by means of lessons learnt from research on Merino sheep, which were divergently selected for their multiple rearing ability. These two selection lines have shown marked differences in reproduction, production and welfare, which makes this breeding programme ideal to investigate potential genetic markers of robustness. The HPAA function is explored in detail to elucidate where such genetic markers are likely to be found. PMID:26487412

  19. Convergence of stem cell behaviors and genetic regulation between animals and plants: insights from the Arabidopsis thaliana stomatal lineage

    PubMed Central

    Matos, Juliana L.

    2014-01-01

    Plants and animals are two successful, but vastly different, forms of complex multicellular life. In the 1600 million years since they shared a common unicellular ancestor, representatives of these kingdoms have had ample time to devise unique strategies for building and maintaining themselves, yet they have both developed self-renewing stem cell populations. Using the cellular behaviors and the genetic control of stomatal lineage of Arabidopsis as a focal point, we find current data suggests convergence of stem cell regulation at developmental and molecular levels. Comparative studies between evolutionary distant groups, therefore, have the power to reveal the logic behind stem cell behaviors and benefit both human regenerative medicine and plant biomass production. PMID:25184043

  20. The WAG/Rij strain: a genetic animal model of absence epilepsy with comorbidity of depression [corrected].

    PubMed

    Sarkisova, Karine; van Luijtelaar, Gilles

    2011-06-01

    A great number of clinical observations show a relationship between epilepsy and depression. Idiopathic generalized epilepsy, including absence epilepsy, has a genetic basis. The review provides evidence that WAG/Rij rats can be regarded as a valid genetic animal model of absence epilepsy with comorbidity of depression. WAG/Rij rats, originally developed as an animal model of human absence epilepsy, share many EEG and behavioral characteristics resembling absence epilepsy in humans, including the similarity of action of various antiepileptic drugs. Behavioral studies indicate that WAG/Rij rats exhibit depression-like symptoms: decreased investigative activity in the open field test, increased immobility in the forced swimming test, and decreased sucrose consumption and preference (anhedonia). In addition, WAG/Rij rats adopt passive strategies in stressful situations, express some cognitive disturbances (reduced long-term memory), helplessness, and submissiveness, inability to make choice and overcome obstacles, which are typical for depressed patients. Elevated anxiety is not a characteristic (specific) feature of WAG/Rij rats; it is a characteristic for only a sub-strain of WAG/Rij rats susceptible to audiogenic seizures. Interestingly, WAG/Rij rats display a hyper-response to amphetamine similar to anhedonic depressed patients. WAG/Rij rats are sensitive only to chronic, but not acute, antidepressant treatments, suggesting that WAG/Rij rats fulfill a criterion of predictive validity for a putative animal model of depression. However, more and different antidepressant drugs still await evaluation. Depression-like behavioral symptoms in WAG/Rij rats are evident at baseline conditions, not exclusively after stress. Experiments with foot-shock stress do not point towards higher stress sensitivity at both behavioral and hormonal levels. However, freezing behavior (coping deficits) and blunted response of 5HT in the frontal cortex to uncontrollable sound stress, increased c-fos expression in the terminal regions of the meso-cortico-limbic brain systems and greater DA response of the mesolimbic system to forced swim stress suggest that WAG/Rij rats are vulnerable to some, but not to all types of stressors. We propose that genetic absence epileptic WAG/Rij rats have behavioral depression-like symptoms, are vulnerable to stress and might represent a model of chronic low-grade depression (dysthymia). Both 5HT and DAergic abnormalities detected in the brain of WAG/Rij rats are involved in modulation of vulnerability to stress and provocation of behavioral depression-like symptoms. The same neurotransmitter systems modulate SWDs as well. Recent studies suggest that the occurrence and repetition of absence seizures are a precipitant of depression-like behavior. Whether the neurochemical changes are primary to depression-like behavioral alterations remains to be determined. In conclusion, the WAG/Rij rats can be considered as a genetic animal model for absence epilepsy with comorbidity of dysthymia. This model can be used to investigate etiology, pathogenic mechanisms and treatment of a psychiatric comorbidity, such as depression in absence epilepsy, to reveal putative genes contributing to comorbid depressive disorder, and to screen novel psychotropic drugs with a selective and/or complex (dual) action on both pathologies. PMID:21093520

  1. Genetically engineered multivalent single chain antibody constructs for cancer therapy

    SciTech Connect

    Surinder Batra, Ph.D.

    2006-02-27

    Current therapeutic approaches against the advanced stages of human solid tumors are palliative rather than curative. Many modalities, including, surgery, radiation, and chemotherapy, either alone or in combination have met with only modest success for advanced metastatic cancers. Radioimmunotherapy (RIT) combines the specificity of monoclonal antibodies with cytotxic effects of radioisotopes. It is the ?smart? way of delivering radiation to the known and occult metastatic cancer cells and is independent of drug toxicity and/or hormone resistance. The tumor associated glycoprotein-72 (TAG-72) containing the unique disaccharide sialyl-Tn, is highly expressed in majority of adenocarcinomas, including carcinomas of the prostate, breast, ovaries, pancreas and colon (80-90%) compared to undetectable expression in normal tissues. Monoclonal antibody CC49, reactive with TAG-72, after conjugation to potent gamma- and beta-emitting radionuclides, has been useful in selective systemic radiolocalization of disease and therapy of primary and metastatic tumor sites. However, limited therapeutic responses were observed in patients. Limited success of antibody based delivery of radioisotopes can be attributed to several factors including undesirable pharmacokinetics, poor tumor uptake and high immunogenicity of intact antibodies (IgGs). The primary factors contributing towards the failure of RIT include: 1) longer serum half-lives of the intact IgG molecules resulting in the radiotoxicity, 2) generation of human antibodies against murine antibodies (HAMA) that limits the frequency of dose administration, 3) poor diffusion rates of intact IgG due to the large size and 4) high interstitial fluid pressures (IFP) encountered in solid tumors. The major goal of our multidisciplinary project was to develop specific novel radiopharmaceuticals, with desired pharmacokinetics, for the diagnosis and therapy of solid tumors. To overcome the low uptake of radioactivity by tumors and to increase its tumor: normal tissue ratio for improved therapeutic index, we engineered a variety antibody constructs. These constructs were evaluated using novel approaches like special radionuclides, pretargeting and optimization. Due to the smaller size, the engineered antibody molecules should penetrate better throughout a tumor mass, with less dose heterogeneity, than is the case with intact IgG. Multivalent scFvs with an appropriate radionuclide, therefore, hold promising prospects for cancer therapy and clinical imaging in MAb-based radiopharmaceuticals. In addition, the human anti-mouse antibodies (HAMA) responses in patients against antibody-based therapy are usually directed against the immunoglobulin constant regions; however, anti-idiotypic responses can also be detected. The HAMA responses reduce the efficacy of treatment by removing the circulating antibody molecules, fragments, and possibly scFvs by altering the pharmacokinetic properties of the antibody. HAMA responses against divalent IgG, divalent Ig fragments, and possibly multimeric scFvs could cause immune complex formation with hypersensitivity or allergic reactions that could be harmful to patients. The use of small molecules, such as scFvs (monomeric as well as multimeric), with their shorter biological half-lives and the lack of the constant regions and humanized variable (binding regions) performed in our studies should reduce the development of HAMA. The generation of humanized and fully human scFvs should further reduce the development of HAMA. Specific accomplishments on the project are the production of large amounts of recombinant antibodies as they are required in large amounts for cancer diagnosis and therapy. A variety of single-chain Fv (scFv) constructs were engineered for the desired pharmacokinetic properties. Tetrameric and dimeric scFvs showed a two-fold advantage: (1) there was a considerable gain in avidity as compared to smaller fragments, and (2) the biological half-life was more compatible with RIT and RIS requirements. For RIT, delivery for sc(Fv)2 and [sc(Fv)2]2 in a fr

  2. Phelan McDermid Syndrome: From Genetic Discoveries to Animal Models and Treatment.

    PubMed

    Harony-Nicolas, Hala; De Rubeis, Silvia; Kolevzon, Alexander; Buxbaum, Joseph D

    2015-12-01

    Phelan-McDermid syndrome or 22q13.3 deletion syndrome is a rare neurodevelopmental disorder characterized by generalized developmental delay, intellectual disability, absent or delayed speech, seizures, autism spectrum disorder, neonatal hypotonia, physical dysmorphic features, and recurrent medical comorbidities. Individuals with Phelan-McDermid syndrome have terminal deletions of the chromosomal region 22q13.3 encompassing SHANK3, a gene encoding a structural component of excitatory synapses indispensable for proper synaptogenesis and neuronal physiology, or point mutations within the gene. Here, we review the clinical aspects of the syndrome and the genetic findings shedding light onto the underlying etiology. We also provide an overview on the evidence from genetic studies and mouse models that supports SHANK3 haploinsufficiency as a major contributor of the neurobehavioral manifestations of Phelan-McDermid syndrome. Finally, we discuss how all these discoveries are uncovering the pathophysiology of Phelan-McDermid syndrome and are being translated into clinical trials for novel therapeutics ameliorating the core symptoms of the disorder. PMID:26350728

  3. Biosynthesis and characterization of CdS quantum dots in genetically engineered Escherichia coli

    PubMed Central

    Mi, Congcong; Wang, Yanyan; Zhang, Jingpu; Huang, Huaiqing; Xu, Linru; Wang, Shuo; Fang, Xuexun; Fang, Jin; Mao, Chuanbin; Xu, Shukun

    2011-01-01

    Quantum dots (QDs) were prepared in genetically engineered Escherichia coli (E. coli) through the introduction of foreign genes encoding a CdS binding peptide. The CdS QDs were successfully separated from the bacteria through two methods, lysis and freezing–thawing of cells, and purified with an anion-exchange resin. High-resolution transmission electron microscopy, X-ray diffraction, luminescence spectroscopy, and energy dispersive X-ray spectroscopy were applied to characterize the as-prepared CdS QDs. The effects of reactant concentrations, bacteria incubation times, and reaction times on QD growth were systematically investigated. Our work demonstrates that genetically engineered bacteria can be used to synthesize QDs. The biologically synthesized QDs are expected to be more biocompatible probes in bio-labeling and imaging. PMID:21458508

  4. Genetic engineering of woody plants: current and future targets in a stressful environment.

    PubMed

    Osakabe, Yuriko; Kajita, Shinya; Osakabe, Keishi

    2011-06-01

    Abiotic stress is a major factor in limiting plant growth and productivity. Environmental degradation, such as drought and salinity stresses, will become more severe and widespread in the world. To overcome severe environmental stress, plant biotechnologies, such as genetic engineering in woody plants, need to be implemented. The adaptation of plants to environmental stress is controlled by cascades of molecular networks including cross-talk with other stress signaling mechanisms. The present review focuses on recent studies concerning genetic engineering in woody plants for the improvement of the abiotic stress responses. Furthermore, it highlights the recent advances in the understanding of molecular responses to stress. The review also summarizes the basis of a molecular mechanism for cell wall biosynthesis and the plant hormone responses to regulate tree growth and biomass in woody plants. This would facilitate better understanding of the control programs of biomass production under stressful conditions. PMID:21288247

  5. Selection systems based on dominant-negative transcription factors for precise genetic engineering

    PubMed Central

    Dutoit, Raphaël; Dubois, Evelyne; Jacobs, Eric

    2010-01-01

    Diverse tools are available for performing genetic modifications of microorganisms. However, new methods still need to be developed for performing precise genomic engineering without introducing any undesirable side-alteration. Indeed for functional analyses of genomic elements, as well as for some industrial applications, only the desired mutation should be introduced at the locus considered. This article describes a new approach fulfilling these requirements, based on the use of selection systems consisting in truncated genes encoding dominant-negative transcription factors. We have demonstrated dominant-negative effects mediated by truncated Gal4p and Arg81p proteins in Saccharomyces cerevisiae, interfering with galactose and arginine metabolic pathways, respectively. These genes can be used as positive and negative markers, since they provoke both growth inhibition on substrates and resistance to specific drugs. These selection markers have been successfully used for precisely deleting HO and URA3 in wild yeasts. This genetic engineering approach could be extended to other microorganisms. PMID:20702421

  6. Genetically engineered theranostic mesenchymal stem cells for the evaluation of the anticancer efficacy of enzyme/prodrug systems.

    PubMed

    Nouri, Faranak Salman; Wang, Xing; Hatefi, Arash

    2015-02-28

    Over the past decade, various enzyme/prodrug systems such as thymidine kinase/ganciclovir (TK/GCV), yeast cytosine deaminase/5-fluorocytosine (yCD/5-FC) and nitroreductase/CB1954 (NTR/CB1954) have been used for stem cell mediated suicide gene therapy of cancer. Yet, no study has been conducted to compare and demonstrate the advantages and disadvantages of using one system over another. Knowing that each enzyme/prodrug system has its own strengths and weaknesses, we utilized mesenchymal stem cells (MSCs) as a medium to perform for the first time a comparative study that illustrated the impact of subtle differences among these systems on the therapeutic outcome. For therapeutic purposes, we first genetically modified MSCs to stably express a panel of four suicide genes including TK (TK007 and TK(SR39) mutants), yeast cytosine deaminase:uracil phosphoribosyltransferase (yCD:UPRT) and nitroreductase (NTR). Then, we evaluated the anticancer efficacies of the genetically engineered MSCs in vitro and in vivo by using SKOV3 cell line which is sensitive to all four enzyme/prodrug systems. In addition, all MSCs were engineered to stably express luciferase gene making them suitable for quantitative imaging and dose-response relationship studies in animals. Considering the limitations imposed by the prodrugs' bystander effects, our findings show that yCD:UPRT/5-FC is the most effective enzyme/prodrug system among the ones tested. Our findings also demonstrate that theranostic MSCs are a reliable medium for the side-by-side evaluation and screening of the enzyme/prodrug systems at the preclinical level. The results of this study could help scientists who utilize cell-based, non-viral or viral vectors for suicide gene therapy of cancer make more informed decisions when choosing enzyme/prodrug systems. PMID:25575867

  7. Chemical modifications and genetic engineering of food proteins.

    PubMed

    Richardson, T

    1985-10-01

    Relationships of structure to function of proteins can be studied using chemical modifications of amino-acid side chains and, more recently, recombinant deoxyribonucleic acid techniques to alter primary sequences. A wide array of chemical modifications are available to the food chemist for manipulating the functionality of food proteins. The esterification of side-chain carboxyl groups in proteins to yield polycationic polymers is emphasized in this review as an example of changing the functionality of a protein via chemical derivatization. However, chemical modifications of proteins generally suffer from a lack of control in the extent of derivatization attainable, oftentimes yielding polydisperse products. Recent advances in recombinant deoxyribonucleic acid technology offer the opportunity to relate systematically well-defined alterations in the primary sequence to changes in protein functionality. Using oligonucleotide-directed mutagenesis, one can now use synthetic oligodeoxynucleotides to prepare semisynthetic genes coding for specific changes in the primary sequence of proteins. Incorporation of the altered genes into an appropriate host can lead to the production of the modified protein for structure-function relationship studies. These recombinant deoxyribonucleic acid techniques may eventually provide the means to engineer proteins and enzymes. PMID:3864797

  8. Lipidomic analysis of Arabidopsis seed genetically engineered to contain DHA

    PubMed Central

    Zhou, Xue-Rong; Callahan, Damien L.; Shrestha, Pushkar; Liu, Qing; Petrie, James R.; Singh, Surinder P.

    2014-01-01

    Metabolic engineering of omega-3 long-chain (?C20) polyunsaturated fatty acids (?3 LC-PUFA) in oilseeds has been one of the key targets in recent years. By expressing a transgenic pathway for enhancing the synthesis of the ?3 LC-PUFA docosahexaenoic acid (DHA) from endogenous ?-linolenic acid (ALA), we obtained the production of fish oil-like proportions of DHA in Arabidopsis seed oil. Liquid chromatography-mass spectrometry (LC-MS) was used to characterize the triacylglycerol (TAG), diacylglycerol (DAG) and phospholipid (PL) lipid classes in the transgenic and wild type Arabidopsis seeds at both developing and mature stages. The analysis identified the appearance of several abundant DHA-containing phosphatidylcholine (PC), DAG and TAG molecular species in mature seeds. The relative abundances of PL, DAG, and TAG species showed a preferred combination of LC-PUFA with ALA in the transgenic seeds, where LC-PUFA were esterified in positions usually occupied by 20:1?9. Trace amounts of di-DHA PC and tri-DHA TAG were identified and confirmed by high resolution MS/MS. Studying the lipidome in transgenic seeds provided insights into where DHA accumulated and combined with other fatty acids of neutral and phospholipids from the developing and mature seeds. PMID:25225497

  9. Tipping Points in Seaweed Genetic Engineering: Scaling Up Opportunities in the Next Decade

    PubMed Central

    Lin, Hanzhi; Qin, Song

    2014-01-01

    Seaweed genetic engineering is a transgenic expression system with unique features compared with those of heterotrophic prokaryotes and higher plants. This study discusses several newly sequenced seaweed nuclear genomes and the necessity that research on vector design should consider endogenous promoters, codon optimization, and gene copy number. Seaweed viruses and artificial transposons can be applied as transformation methods after acquiring a comprehensive understanding of the mechanism of viral infections in seaweeds and transposon patterns in seaweed genomes. After cultivating transgenic algal cells and tissues in a photobioreactor, a biosafety assessment of genetically modified (GM) seaweeds must be conducted before open-sea application. We propose a set of programs for the evaluation of gene flow from GM seaweeds to local/geographical environments. The effective implementation of such programs requires fundamentally systematic and interdisciplinary studies on algal physiology and genetics, marine hydrology, reproductive biology, and ecology. PMID:24857961

  10. Tipping points in seaweed genetic engineering: scaling up opportunities in the next decade.

    PubMed

    Lin, Hanzhi; Qin, Song

    2014-05-01

    Seaweed genetic engineering is a transgenic expression system with unique features compared with those of heterotrophic prokaryotes and higher plants. This study discusses several newly sequenced seaweed nuclear genomes and the necessity that research on vector design should consider endogenous promoters, codon optimization, and gene copy number. Seaweed viruses and artificial transposons can be applied as transformation methods after acquiring a comprehensive understanding of the mechanism of viral infections in seaweeds and transposon patterns in seaweed genomes. After cultivating transgenic algal cells and tissues in a photobioreactor, a biosafety assessment of genetically modified (GM) seaweeds must be conducted before open-sea application. We propose a set of programs for the evaluation of gene flow from GM seaweeds to local/geographical environments. The effective implementation of such programs requires fundamentally systematic and interdisciplinary studies on algal physiology and genetics, marine hydrology, reproductive biology, and ecology. PMID:24857961

  11. Improved metal cluster deposition on a genetically engineered tobacco mosaic virus template.

    PubMed

    Lee, Sang-Yup; Royston, Elizabeth; Culver, James N; Harris, Michael T

    2005-07-01

    Improved depositions of various metal clusters onto a biomolecular template were achieved using a genetically engineered tobacco mosaic virus (TMV). Wild-type TMV was genetically altered to display multiple solid metal binding sites through the insertion of two cysteine residues within the amino-terminus of the virus coat protein. Gold, silver, and palladium clusters synthesized through in situ chemical reductions could be readily deposited onto the genetically modified template via the exposed cysteine-derived thiol groups. Metal cluster coatings on the cysteine-modified template were more densely deposited and stable than similar coatings on the unmodified wild-type template. Combined, these results confirm that the introduction of cysteine residues onto the outer surface of the TMV coat protein enhances the usefulness of this virus as a biotemplate for the deposition of metal clusters. PMID:21727464

  12. Improved metal cluster deposition on a genetically engineered tobacco mosaic virus template

    NASA Astrophysics Data System (ADS)

    Lee, Sang-Yup; Royston, Elizabeth; Culver, James N.; Harris, Michael T.

    2005-07-01

    Improved depositions of various metal clusters onto a biomolecular template were achieved using a genetically engineered tobacco mosaic virus (TMV). Wild-type TMV was genetically altered to display multiple solid metal binding sites through the insertion of two cysteine residues within the amino-terminus of the virus coat protein. Gold, silver, and palladium clusters synthesized through in situ chemical reductions could be readily deposited onto the genetically modified template via the exposed cysteine-derived thiol groups. Metal cluster coatings on the cysteine-modified template were more densely deposited and stable than similar coatings on the unmodified wild-type template. Combined, these results confirm that the introduction of cysteine residues onto the outer surface of the TMV coat protein enhances the usefulness of this virus as a biotemplate for the deposition of metal clusters.

  13. Review of animal models designed to predict the potential allergenicity of novel proteins in genetically modified crops.

    PubMed

    Ladics, G S; Knippels, L M J; Penninks, A H; Bannon, G A; Goodman, R E; Herouet-Guicheney, C

    2010-03-01

    The safety assessment of genetically modified crops involves the evaluation of the potential allergenicity of novel proteins by using several in silico and in vitro endpoints. In this publication, the variables and questions associated with the development of in vivo models are examined and several unpublished results are presented. Both rodent and non-rodent (dog and pig) models have been investigated using various routes of administration with purified proteins or food extracts, with or without the use of an adjuvant. The ideal model should be simple, reproducible across laboratories over time, specific and sensitive enough for distinguishing a threshold beyond which relevant allergenicity would be predicted and, for ranking proteins correlated with the allergic responses in humans, and acceptable under animal care. Preliminary data suggest that a few appear promising; however, further evaluation of these models is required. In particular, more extensive validation testing with additional allergenic and non-allergenic material should be performed before using them in the safety assessment of genetically modified crops. PMID:19800379

  14. Genetic threshold hypothesis of neocortical spike-and-wave discharges in the rat: An animal model of petit mal epilepsy

    SciTech Connect

    Vadasz, C.; Fleischer, A.; Carpi, D.; Jando, G.

    1995-02-27

    Neocortical high-voltage spike-and-wave discharges (HVS) in the rat are an animal model of petit mal epilepsy. Genetic analysis of total duration of HVS (s/12 hr) in reciprocal F1 and F2 hybrids of F344 and BN rats indicated that the phenotypic variability of HVS cannot be explained by simple, monogenic Mendelian model. Biometrical analysis suggested the presence of additive, dominance, and sex-linked-epistatic effects, buffering maternal influence, and heterosis. High correlation was observed between average duration (s/episode) and frequency of occurrence of spike-and-wave episodes (n/12 hr) in parental and segregating generations, indicating that common genes affect both duration and frequency of the spike-and-wave pattern. We propose that both genetic and developmental - environmental factors control an underlying quantitative variable, which, above a certain threshold level, precipitates HVS discharges. These findings, together with the recent availability of rat DNA markers for total genome mapping, pave the way to the identification of genes that control the susceptibility of the brain to spike-and-wave discharges. 67 refs., 3 figs., 5 tabs.

  15. Building Shape Surfactants: Creating rod-coil complexes using genetically engineered viruses

    NASA Astrophysics Data System (ADS)

    Huang, Phil; Fraden, Seth

    2006-03-01

    Complex self-assembled structures (micelles, lamellar phases) are often found in dispersions of amphiphilic molecules like surfactants. We genetically engineered M13 bacteriophage, a long filamentous particle that forms liquid crystalline phases, and coupled a 15 base pair oligonucleotide to one end of the virus. A plasmid DNA fragment was then ligated to the oligonucleotide to form a rod-coil particle. Based on the above complex conjugate, we are attempting to create supramolecular liquid crystalline structures.

  16. [Genetic engineering technologies of stimulating angiogenesis as an innovation trend in angiology and vascular surgery].

    PubMed

    Gavrilenko, A V; Voronov, D A

    2015-01-01

    Presented herein is a review of the principles, fundamental concepts, and possibilities of genetic engineering technologies of stimulating angiogenesis for treatment of patients with lower limb chronic ischaemia. This is followed by a detailed discussion of the structure and results of Russian and foreign studies on this direction, also considering the causes of differences of their results. Outlined is a circle of clinical situations in relation to which these technologies may be regarded as most promising. PMID:26035559

  17. Genetics

    MedlinePLUS

    Homozygous; Inheritance; Heterozygous; Inheritance patterns; Heredity and disease; Heritable; Genetic markers ... The chromosomes are made up of strands of genetic information called DNA. Each chromosome contains sections of ...

  18. A CRISPR-Cas9 System for Genetic Engineering of Filamentous Fungi

    PubMed Central

    Nødvig, Christina S.; Nielsen, Jakob B.; Kogle, Martin E.; Mortensen, Uffe H.

    2015-01-01

    The number of fully sequenced fungal genomes is rapidly increasing. Since genetic tools are poorly developed for most filamentous fungi, it is currently difficult to employ genetic engineering for understanding the biology of these fungi and to fully exploit them industrially. For that reason there is a demand for developing versatile methods that can be used to genetically manipulate non-model filamentous fungi. To facilitate this, we have developed a CRISPR-Cas9 based system adapted for use in filamentous fungi. The system is simple and versatile, as RNA guided mutagenesis can be achieved by transforming a target fungus with a single plasmid. The system currently contains four CRISPR-Cas9 vectors, which are equipped with commonly used fungal markers allowing for selection in a broad range of fungi. Moreover, we have developed a script that allows identification of protospacers that target gene homologs in multiple species to facilitate introduction of common mutations in different filamentous fungi. With these tools we have performed RNA-guided mutagenesis in six species of which one has not previously been genetically engineered. Moreover, for a wild-type Aspergillus aculeatus strain, we have used our CRISPR Cas9 system to generate a strain that contains an AACU_pyrG marker and demonstrated that the resulting strain can be used for iterative gene targeting. PMID:26177455

  19. A CRISPR-Cas9 System for Genetic Engineering of Filamentous Fungi.

    PubMed

    Nødvig, Christina S; Nielsen, Jakob B; Kogle, Martin E; Mortensen, Uffe H

    2015-01-01

    The number of fully sequenced fungal genomes is rapidly increasing. Since genetic tools are poorly developed for most filamentous fungi, it is currently difficult to employ genetic engineering for understanding the biology of these fungi and to fully exploit them industrially. For that reason there is a demand for developing versatile methods that can be used to genetically manipulate non-model filamentous fungi. To facilitate this, we have developed a CRISPR-Cas9 based system adapted for use in filamentous fungi. The system is simple and versatile, as RNA guided mutagenesis can be achieved by transforming a target fungus with a single plasmid. The system currently contains four CRISPR-Cas9 vectors, which are equipped with commonly used fungal markers allowing for selection in a broad range of fungi. Moreover, we have developed a script that allows identification of protospacers that target gene homologs in multiple species to facilitate introduction of common mutations in different filamentous fungi. With these tools we have performed RNA-guided mutagenesis in six species of which one has not previously been genetically engineered. Moreover, for a wild-type Aspergillus aculeatus strain, we have used our CRISPR Cas9 system to generate a strain that contains an AACU_pyrG marker and demonstrated that the resulting strain can be used for iterative gene targeting. PMID:26177455

  20. Use of bioluminescence for detection of genetically engineered microorganisms released into the environment. [Xanthomonas campestris

    SciTech Connect

    Shaw, J.J.; Dane, F.; Geiger, D.; Kloepper, J.W. )

    1992-01-01

    The persistence and movement of strain JS414 of Xanthomonas campestris pv. campestris, which was genetically engineered to bioluminesce, were monitored during a limited field introduction. Bioluminescence and traditional dilution plate counts were determined. Strain JS414 was applied to cabbage plants and surrounding soil by mist inoculation, by wound inoculation, by scattering infested debris among plants, and by incorporating bacteria into the soil. Bioluminescent X. campestris pv. campestris was detected in plant samples and in the rhizosphere up to 6 weeks after inoculation. Movement to uninoculated plants was detected on one occasion, but movement from the immediate release area was not detected. Strain JS414 was detected in soil samples beneath mist- and wound-inoculated plants only at intentionally infested locations and in aerial samples only on the day of inoculation. The authors bioluminescence methods proved to be as sensitive as plating methods for detecting the genetically engineered microorganisms in environmental samples. Their results demonstrate that transgenic incorporation of the luxCDABE operon provides a non-labor-intensive, sensitive detection method for monitoring genetically engineered microorganisms in nature.

  1. A portable expression resource for engineering cross-species genetic circuits and pathways

    PubMed Central

    Kushwaha, Manish; Salis, Howard M.

    2015-01-01

    Genetic circuits and metabolic pathways can be reengineered to allow organisms to process signals and manufacture useful chemicals. However, their functions currently rely on organism-specific regulatory parts, fragmenting synthetic biology and metabolic engineering into host-specific domains. To unify efforts, here we have engineered a cross-species expression resource that enables circuits and pathways to reuse the same genetic parts, while functioning similarly across diverse organisms. Our engineered system combines mixed feedback control loops and cross-species translation signals to autonomously self-regulate expression of an orthogonal polymerase without host-specific promoters, achieving nontoxic and tuneable gene expression in diverse Gram-positive and Gram-negative bacteria. Combining 50 characterized system variants with mechanistic modelling, we show how the cross-species expression resource's dynamics, capacity and toxicity are controlled by the control loops' architecture and feedback strengths. We also demonstrate one application of the resource by reusing the same genetic parts to express a biosynthesis pathway in both model and non-model hosts. PMID:26184393

  2. Small-scale field test of the genetically engineered lacZY marker

    SciTech Connect

    Hattemer-Frey, H.A.; Brandt, E.J.; Travis, C.C. )

    1990-06-01

    Commercial genetic engineering is advancing into areas that require the small-scale introduction of genetically engineered microorganisms (GEMs) to better quantify variables that affect microorganism distribution and survival and to document potential long-term consequences. A recombinant DNA marker system, the lacZY marker, developed by the Monsanto Agricultural Co., enables the distribution and fate of marked fluorescent pseudomonad organisms to be monitored under actual field conditions. Critical evaluation of GEMs under field conditions is imperative if plant-beneficial effects are to be correlated with organism release. This paper evaluates the effectiveness of this marker system and its ability to facilitate the assessment of risks associated with deliberate environmental introductions of genetically engineered microorganisms. Results of prerelease contained growth chamber and field experiments demonstrated that: (1) the scientific risk assessment methodology adopted by Monsanto and approved by the U.S. Environmental Protection Agency was appropriate and comprehensive; (2) the deliberate introduction of a GEM did not pose unacceptable or unforeseen risks to human health or the environment; (3) the lacZY marker is an effective environmental tracking tool; and (4) regulatory oversight should reflect the expected risk and not be excessively burdensome for all GEMs.

  3. A portable expression resource for engineering cross-species genetic circuits and pathways.

    PubMed

    Kushwaha, Manish; Salis, Howard M

    2015-01-01

    Genetic circuits and metabolic pathways can be reengineered to allow organisms to process signals and manufacture useful chemicals. However, their functions currently rely on organism-specific regulatory parts, fragmenting synthetic biology and metabolic engineering into host-specific domains. To unify efforts, here we have engineered a cross-species expression resource that enables circuits and pathways to reuse the same genetic parts, while functioning similarly across diverse organisms. Our engineered system combines mixed feedback control loops and cross-species translation signals to autonomously self-regulate expression of an orthogonal polymerase without host-specific promoters, achieving nontoxic and tuneable gene expression in diverse Gram-positive and Gram-negative bacteria. Combining 50 characterized system variants with mechanistic modelling, we show how the cross-species expression resource's dynamics, capacity and toxicity are controlled by the control loops' architecture and feedback strengths. We also demonstrate one application of the resource by reusing the same genetic parts to express a biosynthesis pathway in both model and non-model hosts. PMID:26184393

  4. Current status of genetic engineering in cotton (Gossypium hirsutum L): an assessment.

    PubMed

    Chakravarthy, Vajhala S K; Reddy, Tummala Papi; Reddy, Vudem Dashavantha; Rao, Khareedu Venkateswara

    2014-06-01

    Cotton is considered as the foremost commercially important fiber crop and is deemed as the backbone of the textile industry. The productivity of cotton crop, worldwide, is severely hampered by the occurrence of pests, weeds, pathogens apart from various environmental factors. Several beneficial agronomic traits, viz., early maturity, improved fiber quality, heat tolerance, etc. have been successfully incorporated into cotton varieties employing conventional hybridization and mutation breeding. Crop losses, due to biotic factors, are substantial and may be reduced through certain crop protection strategies. In recent years, pioneering success has been achieved through the adoption of modern biotechnological approaches. Genetically engineered cotton varieties, expressing Bacillus thuringiensis cry genes, proved to be highly successful in controlling the bollworm complex. Various other candidate genes responsible for resistance to insect pests and pathogens, tolerance to major abiotic stress factors such as temperature, drought and salinity, have been introduced into cotton via genetic engineering methods to enhance the agronomic performance of cotton cultivars. Furthermore, genes for improving the seed oil quality and fiber characteristics have been identified and introduced into cotton cultivars. This review provides a brief overview of the various advancements made in cotton through genetic engineering approaches. PMID:23190258

  5. [Study on the efficacy of genetically engineered vaccines against hepatitis B for interruption of perinatal transmission].

    PubMed

    Kang, P; Shen, X M; Yu, H M

    1995-07-01

    The infectivity rate of newborn babies who had been borne from HBsAG(+), HBeAg(+) and anti-HBc(+) mothers was very high (85%). 142 babies born in the hospital were divided into three groups, in this study. In the group 1, 57 babies were inoculated with 20 micrograms recombinant DNA vaccinia vaccines against hepatitis B. The injections were given at newborn, 1 month, and 6 months, respectively. In group 2, 41 babies were inoculated with 20 micrograms genetic engineering vaccines against hepatitis B at same time were intervals as group 1. In group 3, 44 newborn babies were inoculated with 10 micrograms as same vaccines as group 2 HBIG plus 1ml (200 U/ml), at same time intervals as group 1. The immune pretection rates of newborn babies in three groups were 88.2%, 85.9% and 100%, respectively. The anti-HBs pasitive conversion rates were 82%, 86% and 98%, respectively. The group 3 was compared with group 1 and 2. Statistical analysis showed the significant differences (P < 0.05). The result showed the immune program of group 3 was superior to that of group 1 and 2, and none of the 44 babies in group 3 were infected. The efficacy of immunization by genetic engineering vaccines were superior to that of blood-derived vaccine. The genetic engineering vaccines against hepatitis B would be more useful for interruption of perinatal transmission of HBV. PMID:8631089

  6. Threshold voltage control in organic thin film transistors with dielectric layer modified by a genetically engineered polypeptide

    E-print Network

    Dezieck, Alex; Acton, Orb; Leong, Kirsty; Oren, Ersin Emre; Ma, Hong; Tamerler, Candan; Sarikaya, Mehmet; Jen, Alex K.-Y.

    2010-01-01

    Precise control over the threshold voltage of pentacene-based organic thin film transistors was achieved by inserting a genetically engineered quartz-binding polypeptide at the semiconductor-dielectric interface. A 30 V range was accessed...

  7. Dr. Campbell's Bio111 Exam #4 Spring 2007 Biology 111 In-Class Exam #4 Cancer, HIV, & Genetic Engineering

    E-print Network

    Campbell, A. Malcolm

    Dr. Campbell's Bio111 Exam #4 ­ Spring 2007 1 Biology 111 In-Class Exam #4 ­ Cancer, HIV, & Genetic Engineering There is no time limit on this test, though I have tried to design one that you should be able

  8. A CAL Program to Teach the Basic Principles of Genetic Engineering--A Change from the Traditional Approach.

    ERIC Educational Resources Information Center

    Dewhurst, D. G.; And Others

    1989-01-01

    An interactive computer-assisted learning program written for the BBC microcomputer to teach the basic principles of genetic engineering is described. Discussed are the hardware requirements software, use of the program, and assessment. (Author/CW)

  9. FIELD CALIBRATION OF SOIL-CORE MICROCOSMS FOR EVALUATING FATE AND EFFECTS OF GENETICALLY ENGINEERED MICROORGANISMS IN TERRESTRIAL ECOSYSTEMS

    EPA Science Inventory

    Pacific Northwest Laboratory compared intact soil-core microcosms and the field for ecosystem structural and functional properties after the introduction of a model genetically engineered microorganism (GEM). This project used two distinct microbial types as model GEMs, Gram nega...

  10. INTACT SOIL-CORE MICROCOSMS FOR EVALUATING THE FATE AND ECOLOGICAL IMPACT OF THE RELEASE OF GENETICALLY ENGINEERED MICROORGANISMS

    EPA Science Inventory

    Intact soil-core microcosms were studied to determine their applicability for evaluating the transport, survival and potential ecosystem effects of genetically engineered microorganisms before they are released into the environment. oi1-core microcosms were planted with wheat and...

  11. EVALUATION OF METHODS FOR DETECTING ECOLOGICAL EFFECTS FROM GENETICALLY ENGINEERED MICROORGANISMS AND PEST CONTROL AGENTS IN TERRESTRIAL SYSTEMS

    EPA Science Inventory

    This report summarizes and evaluates research from several laboratories that deals with the detection of ecological effects induced through exposure of microbes or plants to genetically engineered microorganisms (GEMS) and microbial pest control agents (MPCAS) . The development o...

  12. Anatomical and genetic study of an ancient animal tooth showing brachyodont and hypsodont mixed taxonomical characteristics.

    PubMed

    Monteagudo, L V; Obón, J A; Whyte, A; Tejedor, M T; Whyte, J; Cisneros, A

    2013-05-01

    A non-human dental piece was found in a Roman Empire tomb dated the 3rd century A.C. in Zaragoza (Spain). The morphology of this piece showed mixed brachyodont (carnivores) and hypsodont (herbivores) characteristics. As a result, the taxonomical assignation of the piece was impossible. Therefore, a protocol based on the DNA sequence of the cytochrome c oxidase subunit 1 mitochondrial region (COI) was applied. For this purpose, a pair of primers able to amplify this region in a large variety of animals was designed. The results point to a species of the Genus Bos (Family Bovidae). This assignation was later confirmed by these quencing of a short fragment of the mitochondrial D-loop region. A complete morphological description of the tooth is presented together with the DNA sequence study and comparison protocol. PMID:23740506

  13. Bone Marrow Transplantation in Mice as a Tool to Generate Genetically Modified Animals

    NASA Astrophysics Data System (ADS)

    R?szer, Tamás; Pintye, Éva; Benk?, Ilona

    2008-12-01

    Transgenic mice can be used either as models of known inherited human diseases or can be applied to perform phenotypic tests of genes with unknown function. In some special applications of gene modification we have to create a tissue specific mutation of a given gene. In some cases however the gene modification can be lethal in the intrauterine life, therefore we should engraft the mutated cells in the postnatal life period. After total body irradiation transplantation of bone marrow cells can be a solution to introduce mutant hematopoietic stem cells into a mature animal. Bone marrow transplantation is a useful and novel tool to study the role of hematopoietic cells in the pathogenesis of inflammation, autoimmune syndromes and many metabolic alterations coupled recently to leukocyte functions.

  14. Bone Marrow Transplantation in Mice as a Tool to Generate Genetically Modified Animals

    SciTech Connect

    Roszer, Tamas; Pintye, Eva; Benko', Ilona

    2008-12-08

    Transgenic mice can be used either as models of known inherited human diseases or can be applied to perform phenotypic tests of genes with unknown function. In some special applications of gene modification we have to create a tissue specific mutation of a given gene. In some cases however the gene modification can be lethal in the intrauterine life, therefore we should engraft the mutated cells in the postnatal life period. After total body irradiation transplantation of bone marrow cells can be a solution to introduce mutant hematopoietic stem cells into a mature animal. Bone marrow transplantation is a useful and novel tool to study the role of hematopoietic cells in the pathogenesis of inflammation, autoimmune syndromes and many metabolic alterations coupled recently to leukocyte functions.

  15. The apoptotic initiator caspase-8: its functional ubiquity and genetic diversity during animal evolution.

    PubMed

    Sakamaki, Kazuhiro; Shimizu, Kouhei; Iwata, Hiroaki; Imai, Kenichiro; Satou, Yutaka; Funayama, Noriko; Nozaki, Masami; Yajima, Mamiko; Nishimura, Osamu; Higuchi, Mayura; Chiba, Kumiko; Yoshimoto, Michi; Kimura, Haruna; Gracey, Andrew Y; Shimizu, Takashi; Tomii, Kentaro; Gotoh, Osamu; Akasaka, Koji; Sawasaki, Tatsuya; Miller, David J

    2014-12-01

    The caspases, a family of cysteine proteases, play multiple roles in apoptosis, inflammation, and cellular differentiation. Caspase-8 (Casp8), which was first identified in humans, functions as an initiator caspase in the apoptotic signaling mediated by cell-surface death receptors. To understand the evolution of function in the Casp8 protein family, casp8 orthologs were identified from a comprehensive range of vertebrates and invertebrates, including sponges and cnidarians, and characterized at both the gene and protein levels. Some introns have been conserved from cnidarians to mammals, but both losses and gains have also occurred; a new intron arose during teleost evolution, whereas in the ascidian Ciona intestinalis, the casp8 gene is intronless and is organized in an operon with a neighboring gene. Casp8 activities are near ubiquitous throughout the animal kingdom. Exogenous expression of a representative range of nonmammalian Casp8 proteins in cultured mammalian cells induced cell death, implying that these proteins possess proapoptotic activity. The cnidarian Casp8 proteins differ considerably from their bilaterian counterparts in terms of amino acid residues in the catalytic pocket, but display the same substrate specificity as human CASP8, highlighting the complexity of spatial structural interactions involved in enzymatic activity. Finally, it was confirmed that the interaction with an adaptor molecule, Fas-associated death domain protein, is also evolutionarily ancient. Thus, despite structural diversity and cooption to a variety of new functions, the ancient origins and near ubiquitous distribution of this activity across the animal kingdom emphasize the importance and utility of Casp8 as a central component of the metazoan molecular toolkit. PMID:25205508

  16. Environmental concerns associated with the design of genetic engineering facilities.

    PubMed

    Watt, J C; Wroniewicz, V S; Ioli, D F

    1988-01-01

    Recombinant DNA technology is being used to produce a wide spectrum of products, such as vaccines, interferon, insulin, and growth hormones. In the design of facilities employing this technology, critical consideration must be given to the protection of the environment, both in the prevention of releases of recombinant DNA organisms into the environment and in the treatment of wastes originating from the production facilities. The design requirements for containment of large-scale systems are complex and require detailed analysis to insure that the containment system can handle both the normal and emergency releases of recombinant DNA organisms. This must include the prevention of releases through either liquid discharges or air emissions. The "killing" method used in the process for either the cells (extracellular product) or the broth (intracellular product) is an important step and can have significant implications in downstream treatment of wastewaters. Since fermentation is the primary process used in the production of recombinant DNA products, wastewater characteristics from this area of the process are basically similar to those of other fermentation processes. They differ, however, because of the "killing" step in the process, which can introduce compounds not normally found in fermentation wastewaters. This can complicate the treatment process by requiring additional treatment operations. Characteristics of wastewaters from other areas of the process can be very diverse, and no general characterization can be made. Techniques for recovery and purification can vary from product to product or even from plant to plant, making characterization difficult. It is important, therefore, that each process be examined in detail so that waste characterization is meaningful and useful in the design of treatment facilities. Because of the complex nature of the processes involved in the production of recombinant DNA products, wastewater treatment can also become a very complex problem. Systems to treat these wastewaters can include many diverse unit operations, from pretreatment of selected streams to tertiary treatment of the combined streams to meet stringent effluent criteria. While biological treatment is almost always applicable, waste loads are very high, and multiple-stage systems could be required. Early and ongoing interface between the process development scientists and engineers and the environmental disciplines allows for the early recognition of potential environmental problems. With early recognition, many of these problems can be economically and efficiently addressed in the design of the facility.(ABSTRACT TRUNCATED AT 400 WORDS) PMID:3178641

  17. Markstein et al. (2008) Nature Genetics Supplementary PDF Exploiting position effects and the gypsy retrovirus insulator to engineer

    E-print Network

    Perrimon, Norbert

    2008-01-01

    Markstein et al. (2008) Nature Genetics Supplementary PDF Exploiting position effects and the gypsy retrovirus insulator to engineer precisely expressed transgenes Michele Markstein1 , Chrysoula Pitsouli1 , Christians Villalta1 , Susan E. Celniker2 , and Norbert Perrimon1 1 Department of Genetics and Howard Hughes

  18. Self-association and modification of a genetically engineered polypeptide

    NASA Astrophysics Data System (ADS)

    Top, Ayben

    A genetically synthesized polypeptide and polyethylene glycol (5 kDa or 10 kDa) functionalized forms of its alanine-rich helical domain were characterized. The polypeptide composed of an N-terminal histidine tag, and an alanine-rich domain, denoted as 17H6, has a sequence of: MGH10 SSGHIHM(AAAQEAAAAQAAAQAEAAQAAQ)6AGGYGGMG. 17H6 was originally designed as a scaffold to investigate multivalent interactions after glycosylation through reactive glutamic acid residues. We speculated that the protonation of the glutamic acid residues in these sequences would afford facile opportunities to manipulate their folding and assembly behavior considering the beta-sheet propensities of similar polypeptides at acidic pH. Thus, in the first part of this study, thermal unfolding, reversible self-association, and irreversible aggregation of 17H6 were investigated. Dynamic light scattering, and thermal unfolding measurements indicate that 17H6 spontaneously and reversibly self-associates at an acidic pH and ambient temperature. The resulting multimers have an average hydrodynamic radius of ˜ 10-20 nm and reversibly dissociate to monomers upon an increase to pH 7.4. Both free monomer and 17H6 chains within the multimers are beta-helical and folded at ambient and sub-ambient temperatures. Reversible unfolding of the monomer occurs upon heating of solutions at pH 7.4. At pH 2.3, heating first causes incomplete dissociation and unfolding of the constituent chains. Further incubation at an elevated temperature (80°C) induces additional structural and morphological changes and results in fibrils with a beta-sheet structure and a width of 5-10 nm (7 nm mean) as observed via transmission electron microscopy (TEM). In the second part, the histidine tag, which imparts solubility to the alanine-rich domain at acidic pH was cleaved. Propionaldehyde-functionalized poly(ethylene glycol) (PEG) molecules (5 kDa or 10 kDa) were attached to the N-terminus of the cleaved polypeptide, c17H6, as a hydrophilic block to compare the effect of these solubility tags on the aggregation and conformation behavior of the alanine-rich domain. Circular dichroic spectroscopy showed that the alpha-helical conformation of the alanine-rich domain was conserved in the conjugates below and near ambient temperatures independent of pH. Similarly, no significant difference between the thermal denaturation behavior of the polypeptide and that of the conjugates was observed at neutral pH. At acidic pH, on the other hand, 17H6 exhibited ˜ 25% loss in the initial alpha-helical structure upon incubation at 80°C for 3 hours followed by the refolding experiments, whereas the initial alpha-helical content of the conjugates did not change. Comparison of the apparent melting temperatures (˜ 54°C for 17H6 and PEG5K-c17H6 and ˜ 51°C for PEG10K-c17H6) indicated that high temperature stability of the conjugates is not due to the stabilization of the native alpha-helical conformation upon PEGylation. Kinetic experiments at 80 ¡aC for prolonged intervals indicated that PEGylation slowed down the rate of beta-sheet formation and reduced apparent cooperativity. These findings suggest that improved stability of the conjugates at acidic pH is due to the stabilization of the intermediate structures (which is likely to be random coil or early stage of beta-sheet structures) that form prior to the aggregation by reducing the interactions between these intermediates. In contrast to the polypeptide fibrils with ˜ 7 nm width, TEM images of the conjugates incubated at 80°C for 18 hours showed fibrillar structures with a width of ˜ 20-30 nm. Thus, it is likely that PEG conjugation also interferes to the arrangement of the polypeptide chains during or prior to the fibril formation. In the third part of this study, the aggregates of the polypeptide and the PEG-polypeptide conjugates that form at the physiological or sub-physiological temperatures and an acidic pH were characterized in detail via dynamic light scattering (DLS), small angle neutron scattering (SANS) and cryogenic transmission electro

  19. Whole-body multicolor spectrally resolved fluorescence imaging for development of target-specific optical contrast agents using genetically engineered probes

    NASA Astrophysics Data System (ADS)

    Kobayashi, Hisataka; Hama, Yukihiro; Koyama, Yoshinori; Barrett, Tristan; Urano, Yasuteru; Choyke, Peter L.

    2007-02-01

    Target-specific contrast agents are being developed for the molecular imaging of cancer. Optically detectable target-specific agents are promising for clinical applications because of their high sensitivity and specificity. Pre clinical testing is needed, however, to validate the actual sensitivity and specificity of these agents in animal models, and involves both conventional histology and immunohistochemistry, which requires large numbers of animals and samples with costly handling. However, a superior validation tool takes advantage of genetic engineering technology whereby cell lines are transfected with genes that induce the target cell to produce fluorescent proteins with characteristic emission spectra thus, identifying them as cancer cells. Multicolor fluorescence imaging of these genetically engineered probes can provide rapid validation of newly developed exogenous probes that fluoresce at different wavelengths. For example, the plasmid containing the gene encoding red fluorescent protein (RFP) was transfected into cell lines previously developed to either express or not-express specific cell surface receptors. Various antibody-based or receptor ligand-based optical contrast agents with either green or near infrared fluorophores were developed to concurrently target and validate cancer cells and their positive and negative controls, such as ?-D-galactose receptor, HER1 and HER2 in a single animal/organ. Spectrally resolved fluorescence multicolor imaging was used to detect separate fluorescent emission spectra from the exogenous agents and RFP. Therefore, using this in vivo imaging technique, we were able to demonstrate the sensitivity and specificity of the target-specific optical contrast agents, thus reducing the number of animals needed to conduct these experiments.

  20. Genetic and pathological taste variation: what can we learn from animal models and human disease?

    PubMed

    Bartoshuk, L M

    1993-01-01

    The study of patients with taste disorders (i.e. 'experiments of nature') suggests that the old tongue maps (e.g. sweet on the tip, bitter on the back) that often appear in textbooks are wrong. If they were correct, severing the taste nerves that innervate the front of the tongue would result in a loss of the ability to taste sweet, etc. This does not occur. Severing these nerves has little effect on everyday taste experience because taste nerves inhibit one another. Damaging one nerve abolishes its ability to inhibit others and the release-of-inhibition compensates for the damage. There is sometimes a clinical cost for this redundancy; release-of-inhibition can produce taste phantoms. Genetic variation in taste ability occurs across and within species. For example, about 25% of humans are relatively unresponsive to a variety of sweet and bitter compounds (non-tasters) while another 25% are unusually responsive (supertasters). Supertasters have about four times as many taste buds as non-tasters and have smaller and more densely packed fungiform papillae. Since there are pain fibres associated with taste buds, supertasters are unusually responsive to the oral burn of spices. PMID:8168379

  1. Genetic and phenotypic evidence of the Salmonella enterica serotype Enteritidis human-animal interface in Chile

    PubMed Central

    Retamal, Patricio; Fresno, Marcela; Dougnac, Catherine; Gutierrez, Sindy; Gornall, Vanessa; Vidal, Roberto; Vernal, Rolando; Pujol, Myriam; Barreto, Marlen; González-Acuña, Daniel; Abalos, Pedro

    2015-01-01

    Salmonella enterica serotype Enteritidis is a worldwide zoonotic agent that has been recognized as a very important food-borne bacterial pathogen, mainly associated with consumption of poultry products. The aim of this work was to determine genotypic and phenotypic evidence of S. Enteritidis transmission among seabirds, poultry and humans in Chile. Genotyping was performed using PCR-based virulotyping, pulse-field gel electrophoresis (PFGE) and multi-locus sequence typing (MLST). Pathogenicity-associated phenotypes were determined with survival to free radicals, acidic pH, starvation, antimicrobial resistance, and survival within human dendritic cells. As result of PCR and PFGE assays, some isolates from the three hosts showed identical genotypic patterns, and through MLST it was determined that all of them belong to sequence type 11. Phenotypic assays show diversity of bacterial responses among isolates. When results were analyzed according to bacterial host, statistical differences were identified in starvation and dendritic cells survival assays. In addition, isolates from seabirds showed the highest rates of resistance to gentamycin, tetracycline, and ampicillin. Overall, the very close genetic and phenotypic traits shown by isolates from humans, poultry, and seabirds suggest the inter-species transmission of S. Enteritidis bacteria between hosts, likely through anthropogenic environmental contamination that determines infection of seabirds with bacteria that are potentially pathogenic for other susceptible organism, including humans. PMID:26029196

  2. Genetic and phenotypic evidence of the Salmonella enterica serotype Enteritidis human-animal interface in Chile.

    PubMed

    Retamal, Patricio; Fresno, Marcela; Dougnac, Catherine; Gutierrez, Sindy; Gornall, Vanessa; Vidal, Roberto; Vernal, Rolando; Pujol, Myriam; Barreto, Marlen; González-Acuña, Daniel; Abalos, Pedro

    2015-01-01

    Salmonella enterica serotype Enteritidis is a worldwide zoonotic agent that has been recognized as a very important food-borne bacterial pathogen, mainly associated with consumption of poultry products. The aim of this work was to determine genotypic and phenotypic evidence of S. Enteritidis transmission among seabirds, poultry and humans in Chile. Genotyping was performed using PCR-based virulotyping, pulse-field gel electrophoresis (PFGE) and multi-locus sequence typing (MLST). Pathogenicity-associated phenotypes were determined with survival to free radicals, acidic pH, starvation, antimicrobial resistance, and survival within human dendritic cells. As result of PCR and PFGE assays, some isolates from the three hosts showed identical genotypic patterns, and through MLST it was determined that all of them belong to sequence type 11. Phenotypic assays show diversity of bacterial responses among isolates. When results were analyzed according to bacterial host, statistical differences were identified in starvation and dendritic cells survival assays. In addition, isolates from seabirds showed the highest rates of resistance to gentamycin, tetracycline, and ampicillin. Overall, the very close genetic and phenotypic traits shown by isolates from humans, poultry, and seabirds suggest the inter-species transmission of S. Enteritidis bacteria between hosts, likely through anthropogenic environmental contamination that determines infection of seabirds with bacteria that are potentially pathogenic for other susceptible organism, including humans. PMID:26029196

  3. Activation of the macroautophagic system in scrapie-infected experimental animals and human genetic prion diseases

    PubMed Central

    Xu, Yin; Tian, Chan; Wang, Shao-Bin; Xie, Wu-Ling; Guo, Yan; Zhang, Jin; Shi, Qi; Chen, Cao; Dong, Xiao-Ping

    2012-01-01

    Macroautophagy is an important process for removing misfolded and aggregated protein in cells, the dysfunction of which has been directly linked to an increasing number of neurodegenerative disorders. However, the details of macroautophagy in prion diseases remain obscure. Here we demonstrated that in the terminal stages of scrapie strain 263K-infected hamsters and human genetic prion diseases, the microtubule-associated protein 1 light chain 3 (LC3) was converted from the cytosolic form to the autophagosome-bound membrane form. Macroautophagy substrate sequestosome 1 (SQSTM1) and polyubiquitinated proteins were downregulated in the brains of sick individuals, indicating enhanced macroautophagic protein degradation. The levels of mechanistic target of rapamycin (MTOR) and phosphorylated MTOR (p-MTOR) were significantly decreased, which implies that this enhancement of the macroautophagic response is likely through the MTOR pathway which is a negative regulator for the initiation of macroautophagy. Dynamic assays of the autophagic system in the brains of scrapie experimental hamsters after inoculation showed that alterations of the autophagic system appeared along with the deposits of PrPSc in the infected brains. Immunofluorescent assays revealed specific staining of autophagosomes in neurons that were not colocalized with deposits of PrPSc in the brains of scrapie infected hamsters, however, autophagosome did colocalize with PrPSc in a prion-infected cell line after treatment with bafilomycin A1. These results suggest that activation of macroautophagy in brains is a disease-correlative phenomenon in prion diseases. PMID:22874564

  4. Isolation-induced behavioural changes in a genetic animal model of depression.

    PubMed

    Fischer, Christina W; Liebenberg, Nico; Elfving, Betina; Lund, Sten; Wegener, Gregers

    2012-04-21

    Depression is a heterogeneous disorder displaying a range of symptoms including feelings of despair and social withdrawal. Social isolation may complicate the progression of depression and have effects on both behaviour and physiology. The aim of this study was to investigate the effects of social isolation on behavioural and metabolic parameters in a genetic rat model of depression, the Flinders Sensitive and Resistant Line (FSL/FRL) rats. Rats were housed either individually (social isolation) or pair-housed for 5weeks, and subjected to behavioural testing and metabolic evaluation. We found that social isolation erased the characteristic difference in depressive-like behaviour, measured as immobility in the forced swim test, between the FSL and FRL rats. Social isolation affected both strains equally in impairing object recognition memory, while leading to an increased explorative behaviour in the elevated plus maze test. Surprisingly, single-housed FRL rats showed an increased food intake compared to pair-housed FRL rats, whereas no difference in food intake or body weight was evident in FSL rats. Our results indicate that social isolation for 5weeks causes behavioural alterations, independent of strain. As the changes in appetite were only observed in the FRL rats, this may suggest that this strain responds to the stress of isolation by a change in feeding behaviour. PMID:22321459

  5. common in animals (for example, see ref. 17); the lack of functional transfer may reect a stringent barrier imposed by genetic code

    E-print Network

    Kreiman, Gabriel

    ¯ect a stringent barrier imposed by genetic code incompatibilities in animals but not plants. Multiple, probably, or cloned using the TA cloning kit (Invitrogen) followed by sequencing of multiple clones. Maximum precursor proteins were synthesized from cDNA clones and imported into the isolated mitochondria in vitro25

  6. Automated, quantitative cognitive/behavioral screening of mice: for genetics, pharmacology, animal cognition and undergraduate instruction.

    PubMed

    Gallistel, C R; Balci, Fuat; Freestone, David; Kheifets, Aaron; King, Adam

    2014-01-01

    We describe a high-throughput, high-volume, fully automated, live-in 24/7 behavioral testing system for assessing the effects of genetic and pharmacological manipulations on basic mechanisms of cognition and learning in mice. A standard polypropylene mouse housing tub is connected through an acrylic tube to a standard commercial mouse test box. The test box has 3 hoppers, 2 of which are connected to pellet feeders. All are internally illuminable with an LED and monitored for head entries by infrared (IR) beams. Mice live in the environment, which eliminates handling during screening. They obtain their food during two or more daily feeding periods by performing in operant (instrumental) and Pavlovian (classical) protocols, for which we have written protocol-control software and quasi-real-time data analysis and graphing software. The data analysis and graphing routines are written in a MATLAB-based language created to simplify greatly the analysis of large time-stamped behavioral and physiological event records and to preserve a full data trail from raw data through all intermediate analyses to the published graphs and statistics within a single data structure. The data-analysis code harvests the data several times a day and subjects it to statistical and graphical analyses, which are automatically stored in the "cloud" and on in-lab computers. Thus, the progress of individual mice is visualized and quantified daily. The data-analysis code talks to the protocol-control code, permitting the automated advance from protocol to protocol of individual subjects. The behavioral protocols implemented are matching, autoshaping, timed hopper-switching, risk assessment in timed hopper-switching, impulsivity measurement, and the circadian anticipation of food availability. Open-source protocol-control and data-analysis code makes the addition of new protocols simple. Eight test environments fit in a 48 in x 24 in x 78 in cabinet; two such cabinets (16 environments) may be controlled by one computer. PMID:24637442

  7. Genetic modification of hypoxia signaling in animal models and its effect on cancer.

    PubMed

    García-Heredia, J M; Felipe-Abrio, B; Cano, D A; Carnero, A

    2015-02-01

    Conditions that cause hypoxemia or generalized tissue hypoxia, which can last for days, months, or even years, are very common in the human population and are among the leading causes of morbidity, disability, and mortality. Therefore, the molecular pathophysiology of hypoxia and its potential deleterious effects on human health are important issues at the forefront of biomedical research. Generalized hypoxia is a consequence of highly prevalent medical disorders that can severely reduce the capacity for O2 exchange between the air and pulmonary capillaries. In recent years, some of the key O2-dependent signaling pathways have been characterized at the molecular level. In particular, the prolyl hydroxylase (PHD)-hypoxia-inducible factor (HIF) cascade has emerged as the master regulator of a general gene expression program involved in cell/tissue/organ adaptation to hypoxia. Hypoxia has emerged as a critical factor in cancer because it can promote tumor initiation, progression, and resistance to therapy. Beyond its role in neovascularization as a mechanism of tumor adaptation to nutrient and O2 deprivation, hypoxia has been linked to prolonged cellular lifespan and immortalization, the generation of "oncometabolites", deregulation of stem cell proliferation, and inflammation, among other tumor hallmarks. Hypoxia may contribute to cancer through several independent pathways, the inter-connections of which have yet to be elucidated. Furthermore, the relevance of chronic hypoxemia in the initiation and progression of cancer has not been studied in depth in the whole organism. Therefore, we explore here the contributions of hypoxia to the whole organism by reviewing studies on genetically modified mice with alterations in the key molecular factors regulating hypoxia. PMID:25351170

  8. Open Field Release of Genetically Engineered Sterile Male Aedes aegypti in Malaysia

    PubMed Central

    Raduan, Norzahira; Kwee Wee, Lim; Hong Ming, Wong; Guat Ney, Teoh; Rahidah A.A., Siti; Salman, Sawaluddin; Subramaniam, Selvi; Nordin, Oreenaiza; Hanum A.T., Norhaida; Angamuthu, Chandru; Marlina Mansor, Suria; Lees, Rosemary S.; Naish, Neil; Scaife, Sarah; Gray, Pam; Labbé, Geneviève; Beech, Camilla; Nimmo, Derric; Alphey, Luke; Vasan, Seshadri S.; Han Lim, Lee; Wasi A., Nazni; Murad, Shahnaz

    2012-01-01

    Background Dengue is the most important mosquito-borne viral disease. In the absence of specific drugs or vaccines, control focuses on suppressing the principal mosquito vector, Aedes aegypti, yet current methods have not proven adequate to control the disease. New methods are therefore urgently needed, for example genetics-based sterile-male-release methods. However, this requires that lab-reared, modified mosquitoes be able to survive and disperse adequately in the field. Methodology/Principal Findings Adult male mosquitoes were released into an uninhabited forested area of Pahang, Malaysia. Their survival and dispersal was assessed by use of a network of traps. Two strains were used, an engineeredgenetically sterile’ (OX513A) and a wild-type laboratory strain, to give both absolute and relative data about the performance of the modified mosquitoes. The two strains had similar maximum dispersal distances (220 m), but mean distance travelled of the OX513A strain was lower (52 vs. 100 m). Life expectancy was similar (2.0 vs. 2.2 days). Recapture rates were high for both strains, possibly because of the uninhabited nature of the site. Conclusions/Significance After extensive contained studies and regulatory scrutiny, a field release of engineered mosquitoes was safely and successfully conducted in Malaysia. The engineered strain showed similar field longevity to an unmodified counterpart, though in this setting dispersal was reduced relative to the unmodified strain. These data are encouraging for the future testing and implementation of genetic control strategies and will help guide future field use of this and other engineered strains. PMID:22970102

  9. Genetic engineering of plants for improved crop production. (Latest citations from the Biobusiness data base). Published Search

    SciTech Connect

    Not Available

    1992-05-01

    The bibliography contains citations concerning the use of genetic engineering to improve crop production. Genetic alterations of plants to provide insect protection, herbicide resistance, disease resistance, improved quality, and higher yield are discussed. Methods used to develop environmentally tolerant crops that are able to withstand extremes of temperature, reduced water consumption, and reduced fertilizer requirements are examined. Genetic engineering of microorganisms that are beneficial to plants is discussed in a separate bibliography. (Contains 250 citations and includes a subject term index and title list.)

  10. Immobilization of the Glucose-Galactose Receptor Protein onto a Au Electrode Through a Genetically Engineered Cysteine

    E-print Network

    Suni, Ian Ivar

    Immobilization of the Glucose-Galactose Receptor Protein onto a Au Electrode Through a Genetically Engineered Cysteine Residue Jianbin Wang,a Linda A. Luck,b,c and Ian I. Sunia, *,z a Department of Chemical and Biomolecular Engineering, and b Department of Chemistry and Biomolecular Science, Center for Advanced Materials

  11. Field application of a genetically engineered microorganism for polycyclic aromatic hydrocarbon bioremediation process monitoring and control

    SciTech Connect

    Sayler, G.S.; Cox, C.D.; Ripp, S.; Nivens, D.E.; Werner, C.; Ahn, Y.; Matrubutham, U.; Burlage, R.

    1998-11-01

    On October 30, 1996, the US Environmental Protection Agency (EPA) commenced the first test release of genetically engineered microorganisms (GEMs) for use in bioremediation. The specific objectives of the investigation were multifaceted and include (1) testing the hypothesis that a GEM can be successfully introduced and maintained in a bioremediation process, (2) testing the concept of using, at the field scale, reporter organisms for direct bioremediation process monitoring and control, and (3) acquiring data that can be used in risk assessment decision making and protocol development for future field release applications of GEMs. The genetically engineered strain under investigation is Pseudomonas fluorescens strain HK44 (King et al., 1990). The original P. fluorescens parent strain was isolated from polycyclic aromatic hydrocarbon (PAH) contaminated manufactured gas plant soil. Thus, this bacterium is able to biodegrade naphthalene (as well as other substituted naphthalenes and other PAHs) and is able to function as a living bioluminescent reporter for the presence of naphthalene contamination, its bioavailability, and the functional process of biodegradation. A unique component of this field investigation was the availability of an array of large subsurface soil lysimeters. This article describes the experience associated with the release of a genetically modified microorganism, the lysimeter facility and its associated instrumentation, as well as representative data collected during the first eighteen months of operation.

  12. Genetic engineering of crops: a ray of hope for enhanced food security

    PubMed Central

    Gill, Sarvajeet Singh; Gill, Ritu; Tuteja, Renu; Tuteja, Narendra

    2014-01-01

    Crop improvement has been a basic and essential chase since organized cultivation of crops began thousands of years ago. Abiotic stresses as a whole are regarded as the crucial factors restricting the plant species to reach their full genetic potential to deliver desired productivity. The changing global climatic conditions are making them worse and pointing toward food insecurity. Agriculture biotechnology or genetic engineering has allowed us to look into and understand the complex nature of abiotic stresses and measures to improve the crop productivity under adverse conditions. Various candidate genes have been identified and transformed in model plants as well as agriculturally important crop plants to develop abiotic stress-tolerant plants for crop improvement. The views presented here are an attempt toward realizing the potential of genetic engineering for improving crops to better tolerate abiotic stresses in the era of climate change, which is now essential for global food security. There is great urgency in speeding up crop improvement programs that can use modern biotechnological tools in addition to current breeding practices for providing enhanced food security. PMID:24686131

  13. Engineering modular and tunable genetic amplifiers for scaling transcriptional signals in cascaded gene networks

    PubMed Central

    Wang, Baojun; Barahona, Mauricio; Buck, Martin

    2014-01-01

    Synthetic biology aims to control and reprogram signal processing pathways within living cells so as to realize repurposed, beneficial applications. Here we report the design and construction of a set of modular and gain-tunable genetic amplifiers in Escherichia coli capable of amplifying a transcriptional signal with wide tunable-gain control in cascaded gene networks. The devices are engineered using orthogonal genetic components (hrpRS, hrpV and PhrpL) from the hrp (hypersensitive response and pathogenicity) gene regulatory network in Pseudomonas syringae. The amplifiers can linearly scale up to 21-fold the transcriptional input with a large output dynamic range, yet not introducing significant time delay or significant noise during signal amplification. The set of genetic amplifiers achieves different gains and input dynamic ranges by varying the expression levels of the underlying ligand-free activator proteins in the device. As their electronic counterparts, these engineered transcriptional amplifiers can act as fundamental building blocks in the design of biological systems by predictably and dynamically modulating transcriptional signal flows to implement advanced intra- and extra-cellular control functions. PMID:25030903

  14. Engineering modular and tunable genetic amplifiers for scaling transcriptional signals in cascaded gene networks.

    PubMed

    Wang, Baojun; Barahona, Mauricio; Buck, Martin

    2014-08-01

    Synthetic biology aims to control and reprogram signal processing pathways within living cells so as to realize repurposed, beneficial applications. Here we report the design and construction of a set of modular and gain-tunable genetic amplifiers in Escherichia coli capable of amplifying a transcriptional signal with wide tunable-gain control in cascaded gene networks. The devices are engineered using orthogonal genetic components (hrpRS, hrpV and PhrpL) from the hrp (hypersensitive response and pathogenicity) gene regulatory network in Pseudomonas syringae. The amplifiers can linearly scale up to 21-fold the transcriptional input with a large output dynamic range, yet not introducing significant time delay or significant noise during signal amplification. The set of genetic amplifiers achieves different gains and input dynamic ranges by varying the expression levels of the underlying ligand-free activator proteins in the device. As their electronic counterparts, these engineered transcriptional amplifiers can act as fundamental building blocks in the design of biological systems by predictably and dynamically modulating transcriptional signal flows to implement advanced intra- and extra-cellular control functions. PMID:25030903

  15. Genetic variation changes the interactions between the parasitic plant-ecosystem engineer Rhinanthus and its hosts

    PubMed Central

    Rowntree, Jennifer K.; Cameron, Duncan D.; Preziosi, Richard F.

    2011-01-01

    Within-species genetic variation is a potent factor influencing between-species interactions and community-level structure. Species of the hemi-parasitic plant genus Rhinanthus act as ecosystem engineers, significantly altering above- and below-ground community structure in grasslands. Here, we show the importance of genotypic variation within a single host species (barley—Hordeum vulgare), and population-level variation among two species of parasite (Rhinanthus minor and Rhinanthus angustifolius) on the outcome of parasite infection for both partners. We measured host fitness (number of seeds) and calculated parasite virulence as the difference in seed set between infected and uninfected hosts (the inverse of host tolerance). Virulence was determined by genetic variation within the host species and among the parasite species, but R. angustifolius was consistently more virulent than R. minor. The most tolerant host had the lowest inherent fitness and did not gain a fitness advantage over other infected hosts. We measured parasite size as a proxy for transmission ability (ability to infect further hosts) and host resistance. Parasite size depended on the specific combination of host genotype, parasite species and parasite population, and no species was consistently larger. We demonstrate that the outcome of infection by Rhinanthus depends not only on the host species, but also on the underlying genetics of both host and parasite. Thus, genetic variations within host and parasite are probably essential components of the ecosystem-altering effects of Rhinanthus. PMID:21444312

  16. Genetic variation changes the interactions between the parasitic plant-ecosystem engineer Rhinanthus and its hosts.

    PubMed

    Rowntree, Jennifer K; Cameron, Duncan D; Preziosi, Richard F

    2011-05-12

    Within-species genetic variation is a potent factor influencing between-species interactions and community-level structure. Species of the hemi-parasitic plant genus Rhinanthus act as ecosystem engineers, significantly altering above- and below-ground community structure in grasslands. Here, we show the importance of genotypic variation within a single host species (barley-Hordeum vulgare), and population-level variation among two species of parasite (Rhinanthus minor and Rhinanthus angustifolius) on the outcome of parasite infection for both partners. We measured host fitness (number of seeds) and calculated parasite virulence as the difference in seed set between infected and uninfected hosts (the inverse of host tolerance). Virulence was determined by genetic variation within the host species and among the parasite species, but R. angustifolius was consistently more virulent than R. minor. The most tolerant host had the lowest inherent fitness and did not gain a fitness advantage over other infected hosts. We measured parasite size as a proxy for transmission ability (ability to infect further hosts) and host resistance. Parasite size depended on the specific combination of host genotype, parasite species and parasite population, and no species was consistently larger. We demonstrate that the outcome of infection by Rhinanthus depends not only on the host species, but also on the underlying genetics of both host and parasite. Thus, genetic variations within host and parasite are probably essential components of the ecosystem-altering effects of Rhinanthus. PMID:21444312

  17. Genetic engineering of bio-nanoparticles for drug delivery: a review.

    PubMed

    Nishimura, Yuya; Ishii, Jun; Ogino, Chiaki; Kondo, Akihiko

    2014-09-01

    Techniques using nanotechnology in the detection and treatment of cancers have made great progress in multidisciplinary fields. The advances in drug delivery systems (DDSs) have been supported mainly by the development of varied nanoparticles (NPs). Although the NPs based on organic and inorganic materials are integral parts in DDSs, bio-nanoparticles containing biopolymer and virus-like particles (VLPs) are attractive biomaterials for DDSs because of their unique features originating in bio-based materials, such as biocompatibility, biodegradability and low immunogenicity. It is notable that these NPs additionally have a great advantage to enable the easy and flexible alteration of their features by genetic engineering approaches. Controlling the sequence and oligomeric process of polypeptide genes permits a variety of choices in type or size of biopolymeric NPs (e.g., elastin-like polypeptide NPs). In contrast, the functional genes are often inserted into the coding sequences for self-assembled proteins to give the VLPs (e.g., hemagglutinating virus of Japan, adeno-associated virus, human immunodeficiency virus-1, simian virus 40 and hepatitis B virus) additional functions. Thus, genetic engineering readily allow alterations of the properties of NPs (e.g., particle shape, size and stability) and grant of new abilities (e.g., cell-specificity and drug loading and release). In this review, we introduce recent advances in bio-nanoparticles from the standpoint of engineering. PMID:25992449

  18. Genetic and metabolic engineering of microorganisms for the development of new flavor compounds from terpenic substrates.

    PubMed

    Bution, Murillo L; Molina, Gustavo; Abrahão, Meissa R E; Pastore, Gláucia M

    2015-01-01

    Throughout human history, natural products have been the basis for the discovery and development of therapeutics, cosmetic and food compounds used in industry. Many compounds found in natural organisms are rather difficult to chemically synthesize and to extract in large amounts, and in this respect, genetic and metabolic engineering are playing an increasingly important role in the production of these compounds, such as new terpenes and terpenoids, which may potentially be used to create aromas in industry. Terpenes belong to the largest class of natural compounds, are produced by all living organisms and play a fundamental role in human nutrition, cosmetics and medicine. Recent advances in systems biology and synthetic biology are allowing us to perform metabolic engineering at the whole-cell level, thus enabling the optimal design of microorganisms for the efficient production of drugs, cosmetic and food additives. This review describes the recent advances made in the genetic and metabolic engineering of the terpenes pathway with a particular focus on systems biotechnology. PMID:24494701

  19. Genetically engineering cyanobacteria to convert CO?, water, and light into the long-chain hydrocarbon farnesene.

    PubMed

    Halfmann, Charles; Gu, Liping; Gibbons, William; Zhou, Ruanbao

    2014-12-01

    Genetically engineered cyanobacteria offer a shortcut to convert CO2 and H2O directly into biofuels and high value chemicals for societal benefits. Farnesene, a long-chained hydrocarbon (C15H24), has many applications in lubricants, cosmetics, fragrances, and biofuels. However, a method for the sustainable, photosynthetic production of farnesene has been lacking. Here, we report the photosynthetic production of farnesene by the filamentous cyanobacterium Anabaena sp. PCC 7120 using only CO2, mineralized water, and light. A codon-optimized farnesene synthase gene was chemically synthesized and then expressed in the cyanobacterium, enabling it to synthesize farnesene through its endogenous non-mevalonate (MEP) pathway. Farnesene excreted from the engineered cyanobacterium volatilized into the flask head space and was recovered by adsorption in a resin column. The maximum photosynthetic productivity of farnesene was 69.1?±?1.8 ?g·L(-1)·O.D.(-1)·d(-1). Compared to the wild type, the farnesene-producing cyanobacterium also exhibited a 60 % higher PSII activity under high light, suggesting increased farnesene productivity in such conditions. We envision genetically engineered cyanobacteria as a bio-solar factory for photosynthetic production of a wide range of biofuels and commodity chemicals. PMID:25301585

  20. Phytosequestration: Carbon biosequestration by plants and the prospects of genetic engineering

    SciTech Connect

    Jansson, C.; Wullschleger, S.D.; Kalluri, U.C.; Tuskan, G.A.

    2010-07-15

    Photosynthetic assimilation of atmospheric carbon dioxide by land plants offers the underpinnings for terrestrial carbon (C) sequestration. A proportion of the C captured in plant biomass is partitioned to roots, where it enters the pools of soil organic C and soil inorganic C and can be sequestered for millennia. Bioenergy crops serve the dual role of providing biofuel that offsets fossil-fuel greenhouse gas (GHG) emissions and sequestering C in the soil through extensive root systems. Carbon captured in plant biomass can also contribute to C sequestration through the deliberate addition of biochar to soil, wood burial, or the use of durable plant products. Increasing our understanding of plant, microbial, and soil biology, and harnessing the benefits of traditional genetics and genetic engineering, will help us fully realize the GHG mitigation potential of phytosequestration.

  1. Natural plant genetic engineer Agrobacterium rhizogenes: role of T-DNA in plant secondary metabolism.

    PubMed

    Chandra, Sheela

    2012-03-01

    Agrobacterium rhizogenes is a natural plant genetic engineer. It is a gram-negative soil bacterium that induces hairy root formation. Success has been obtained in exploring the molecular mechanisms of transferred DNA (T-DNA) transfer, interaction with host plant proteins, plant defense signaling and integration to plant genome for successful plant genetic transformation. T-DNA and corresponding expression of rol genes alter morphology and plant host secondary metabolism. During transformation, there is a differential loss of a few T-DNA genes. Loss of a few ORFs drastically affect the growth and morphological patterns of hairy roots, expression pattern of biosynthetic pathway genes and accumulation of specific secondary metabolites. PMID:22048847

  2. Engineering antigen-specific T cells from genetically modified human hematopoietic stem cells in immunodeficient mice.

    PubMed

    Kitchen, Scott G; Bennett, Michael; Gali?, Zoran; Kim, Joanne; Xu, Qing; Young, Alan; Lieberman, Alexis; Joseph, Aviva; Goldstein, Harris; Ng, Hwee; Yang, Otto; Zack, Jerome A

    2009-01-01

    There is a desperate need for effective therapies to fight chronic viral infections. The immune response is normally fastidious at controlling the majority of viral infections and a therapeutic strategy aimed at reestablishing immune control represents a potentially powerful approach towards treating persistent viral infections. We examined the potential of genetically programming human hematopoietic stem cells to generate mature CD8+ cytotoxic T lymphocytes that express a molecularly cloned, "transgenic" human anti-HIV T cell receptor (TCR). Anti-HIV TCR transduction of human hematopoietic stem cells directed the maturation of a large population of polyfunctional, HIV-specific CD8+ cells capable of recognizing and killing viral antigen-presenting cells. Thus, through this proof-of-concept we propose that genetic engineering of human hematopoietic stem cells will allow the tailoring of effector T cell responses to fight HIV infection or other diseases that are characterized by the loss of immune control. PMID:19997617

  3. Evaluation of terrestrial microcosms for detection, fate, and survival analysis of genetically engineered microorganisms and their recombinant genetic material

    SciTech Connect

    Fredrickson, J.K.; Seidler, R.J.

    1989-02-01

    The research included in this document represents the current scientific information available regarding the applicability of terrestrial microcosms and related methodologies for evaluating detection methods and the fate and survival of microorganisms in the environment. The three terrestrial microcosms described in this document were used to evaluate the survival and fate of recombinant bacteria in soils and in association with plant surfaces and insects and their transport through soil with percolating water and root systems, and to test new methods and procedures to improve detection and enumeration of bacteria in soil. Simple (potting soil composed of peat mix and perlite, lacking environmental control and monitoring) and complex microcosms (agricultural soil with partial control and monitoring of environmental conditions) were demonstrated to be useful tools for preliminary assessments of microbial viability in terrestrial ecosystems. These studies evaluated the survival patterns of Enterobacter cloacae (pBR322) in soil and on plant surfaces and the ingestion of this same microorganism by cutworms and survival in the foregut and frass. The Versacore microcosm design was used to monitor the fate and competitiveness of genetically engineered bacteria in soil. Both selective media and gene probes were used successfully to follow the fate of two recombinant Pseudomonas sp. introduced into Versacore microcosms. Intact soil-core microcosms were employed to evaluate the fate and transport of genetically altered Azospirillum sp. and Pseudomonas sp. in soil and the plant rhizosphere. The usefulness of these various microcosms as a tool for risk assessment is underscored by the ease in obtaining soil from a proposed field release site to evaluate subsequent GEM fate and survival.

  4. Is genetic engineering ever going to take off in forage, turf and bioenergy crop breeding?

    PubMed Central

    Wang, Zeng-Yu; Brummer, E. Charles

    2012-01-01

    Background Genetic engineering offers the opportunity to generate unique genetic variation that is either absent in the sexually compatible gene pool or has very low heritability. The generation of transgenic plants, coupled with breeding, has led to the production of widely used transgenic cultivars in several major cash crops, such as maize, soybean, cotton and canola. The process for regulatory approval of genetically engineered crops is slow and subject to extensive political interference. The situation in forage grasses and legumes is more complicated. Scope Most widely grown forage, turf and bioenergy species (e.g. tall fescue, perennial ryegrass, switchgrass, alfalfa, white clover) are highly self-incompatible and outcrossing. Compared with inbreeding species, they have a high potential to pass their genes to adjacent plants. A major biosafety concern in these species is pollen-mediated transgene flow. Because human consumption is indirect, risk assessment of transgenic forage, turf and bioenergy species has focused on their environmental or ecological impacts. Although significant progress has been made in genetic modification of these species, commercialization of transgenic cultivars is very limited because of the stringent and costly regulatory requirements. To date, the only transgenic forage crop deregulated in the US is ‘Roundup Ready’ (RR) alfalfa. The approval process for RR alfalfa was complicated, involving several rounds of regulation, deregulation and re-regulation. Nevertheless, commercialization of RR alfalfa is an important step forward in regulatory approval of a perennial outcrossing forage crop. As additional transgenic forage, turf and bioenergy crops are generated and tested, different strategies have been developed to meet regulatory requirements. Recent progress in risk assessment and deregulation of transgenic forage and turf species is summarized and discussed. PMID:22378838

  5. Transcriptomic classification of genetically engineered mouse models of breast cancer identifies human subtype counterparts

    PubMed Central

    2013-01-01

    Background Human breast cancer is a heterogeneous disease consisting of multiple molecular subtypes. Genetically engineered mouse models are a useful resource for studying mammary cancers in vivo under genetically controlled and immune competent conditions. Identifying murine models with conserved human tumor features will facilitate etiology determinations, highlight the effects of mutations on pathway activation, and should improve preclinical drug testing. Results Transcriptomic profiles of 27 murine models of mammary carcinoma and normal mammary tissue were determined using gene expression microarrays. Hierarchical clustering analysis identified 17 distinct murine subtypes. Cross-species analyses using three independent human breast cancer datasets identified eight murine classes that resemble specific human breast cancer subtypes. Multiple models were associated with human basal-like tumors including TgC3(1)-Tag, TgWAP-Myc and Trp53-/-. Interestingly, the TgWAPCre-Etv6 model mimicked the HER2-enriched subtype, a group of human tumors without a murine counterpart in previous comparative studies. Gene signature analysis identified hundreds of commonly expressed pathway signatures between linked mouse and human subtypes, highlighting potentially common genetic drivers of tumorigenesis. Conclusions This study of murine models of breast carcinoma encompasses the largest comprehensive genomic dataset to date to identify human-to-mouse disease subtype counterparts. Our approach illustrates the value of comparisons between species to identify murine models that faithfully mimic the human condition and indicates that multiple genetically engineered mouse models are needed to represent the diversity of human breast cancers. The reported trans-species associations should guide model selection during preclinical study design to ensure appropriate representatives of human disease subtypes are used. PMID:24220145

  6. Genetic Engineering of Trypanosoma (Dutonella) vivax and In Vitro Differentiation under Axenic Conditions

    PubMed Central

    D'Archivio, Simon; Medina, Mathieu; Cosson, Alain; Chamond, Nathalie; Rotureau, Brice; Minoprio, Paola; Goyard, Sophie

    2011-01-01

    Trypanosoma vivax is one of the most common parasites responsible for animal trypanosomosis, and although this disease is widespread in Africa and Latin America, very few studies have been conducted on the parasite's biology. This is in part due to the fact that no reproducible experimental methods had been developed to maintain the different evolutive forms of this trypanosome under laboratory conditions. Appropriate protocols were developed in the 1990s for the axenic maintenance of three major animal Trypanosoma species: T. b. brucei, T. congolense and T. vivax. These pioneer studies rapidly led to the successful genetic manipulation of T. b. brucei and T. congolense. Advances were made in the understanding of these parasites' biology and virulence, and new drug targets were identified. By contrast, challenging in vitro conditions have been developed for T. vivax in the past, and this per se has contributed to defer both its genetic manipulation and subsequent gene function studies. Here we report on the optimization of non-infective T. vivax epimastigote axenic cultures and on the process of parasite in vitro differentiation into metacyclic infective forms. We have also constructed the first T. vivax specific expression vector that drives constitutive expression of the luciferase reporter gene. This vector was then used to establish and optimize epimastigote transfection. We then developed highly reproducible conditions that can be used to obtain and select stably transfected mutants that continue metacyclogenesis and are infectious in immunocompetent rodents. PMID:22216367

  7. The genetic and metabolic determinants of cardiovascular complications in type 2 diabetes: recent insights from animal models and clinical investigations.

    PubMed

    Kohen Avramoglu, Rita; Laplante, Marc-André; Le Quang, Khai; Deshaies, Yves; Després, Jean-Pierre; Larose, Eric; Mathieu, Patrick; Poirier, Paul; Pérusse, Louis; Vohl, Marie-Claude; Sweeney, Gary; Ylä-Herttuala, Seppo; Laakso, Markku; Uusitupa, Matti; Marette, André

    2013-10-01

    Cardiovascular complications (CVC) are the most common causes of death in patients with type 2 diabetes (T2D). However the pathophysiological determinants and molecular mechanisms involved in the progression of CVC in T2D are poorly understood. We have undertaken the challenging task of identifying some of the genetic and clinical determinants of CVC through a unique multidisciplinary approach involving Canadian and Finnish investigators. We are studying novel animal models combining atherosclerosis, diet-induced obesity and T2D to understand the molecular basis of CVC in obesity-linked T2D. We are also conducting clinical studies to identify key determinants of CVC in T2D patients and to determine whether a lifestyle modification program targeting loss of visceral adipose tissue/ectopic fat could be associated with clinical benefits in these patients. Together, we strongly believe that we can fill some gaps in our understanding of the CVC pathogenesis in T2D and identify novel therapeutic targets and hope that this new knowledge may be translated into the design of effective clinical interventions to optimally reduce cardiovascular risk in T2D subjects. PMID:24500564

  8. Field Cage Studies and Progressive Evaluation of Genetically-Engineered Mosquitoes

    PubMed Central

    Facchinelli, Luca; Valerio, Laura; Ramsey, Janine M.; Gould, Fred; Walsh, Rachael K.; Bond, Guillermo; Robert, Michael A.; Lloyd, Alun L.; James, Anthony A.; Alphey, Luke; Scott, Thomas W.

    2013-01-01

    Background A genetically-engineered strain of the dengue mosquito vector Aedes aegypti, designated OX3604C, was evaluated in large outdoor cage trials for its potential to improve dengue prevention efforts by inducing population suppression. OX3604C is engineered with a repressible genetic construct that causes a female-specific flightless phenotype. Wild-type females that mate with homozygous OX3604C males will not produce reproductive female offspring. Weekly introductions of OX3604C males eliminated all three targeted Ae. aegypti populations after 10–20 weeks in a previous laboratory cage experiment. As part of the phased, progressive evaluation of this technology, we carried out an assessment in large outdoor field enclosures in dengue endemic southern Mexico. Methodology/Principal Findings OX3604C males were introduced weekly into field cages containing stable target populations, initially at 10?1 ratios. Statistically significant target population decreases were detected in 4 of 5 treatment cages after 17 weeks, but none of the treatment populations were eliminated. Mating competitiveness experiments, carried out to explore the discrepancy between lab and field cage results revealed a maximum mating disadvantage of up 59.1% for OX3604C males, which accounted for a significant part of the 97% fitness cost predicted by a mathematical model to be necessary to produce the field cage results. Conclusions/Significance Our results indicate that OX3604C may not be effective in large-scale releases. A strain with the same transgene that is not encumbered by a large mating disadvantage, however, could have improved prospects for dengue prevention. Insights from large outdoor cage experiments may provide an important part of the progressive, stepwise evaluation of genetically-engineered mosquitoes. PMID:23350003

  9. 18F-FDG-PET/CT imaging of drug-induced metabolic changes in genetically engineered mouse lung cancer models.

    PubMed

    Wang, Yuchuan; Kung, Andrew L

    2015-02-01

    The most commonly used radiotracer for cancer imaging in humans and mice is 2-deoxy-2-((18)F)fluoro-d-glucose ((18)F-FDG). We have used FDG coupled with positron-emission tomography (PET) to assess the pharmacodynamic efficacy of a number of therapeutics in genetically engineered mouse lung cancer models. In this protocol, we present our approach for FDG-PET imaging of early tumor metabolic changes induced by drug treatment. Special consideration is given to animal preparation, anesthesia, and PET/computed tomography (CT) imaging of mice with lung tumors. Specifically, we recommend fasting the mice overnight to reduce background, using sevoflurane anesthesia and a "conscious" uptake period to minimize cardiac FDG uptake, adopting a relatively short duration of CT and PET scanning to facilitate serial imaging, and quantifying the comparison between the maximum standardized uptake values (SUVs) of lung tumors before and after treatment to determine treatment effects. Used in this manner, FDG-PET can rapidly assess tumor metabolism before and after treatment with an experimental therapeutic. In many cases, metabolic changes are apparent after just a single dose of treatment, helping to show target engagement and modulation by the drug (pharmacodynamic efficacy) within days of starting therapy. PMID:25646497

  10. Crystals of Serum Albumin for Use in Genetic Engineering and Rational Drug Design

    NASA Technical Reports Server (NTRS)

    Carter, Daniel C. (Inventor)

    1996-01-01

    Serum albumin crystal forms have been produced which exhibit superior x-ray diffraction quality. The crystals are produced from both recombinant and wild-type human serum albumin, canine, and baboon serum albumin and allow the performance of drug-binding studies as well as genetic engineering studies. The crystals are grown from solutions of polyethylene glycol or ammonium sulphate within prescribed limits during growth times from one to several weeks and include the following space groups: P2(sub 1), C2, P1.

  11. Experimental therapy of human glioma by means of a genetically engineered virus mutant

    SciTech Connect

    Martuza, R.L.; Malick, A.; Markert, J.M.; Ruffner, K.L.; Coen, D.M. )

    1991-05-10

    Malignant gliomas are the most common malignant brain tumors and are almost always fatal. A thymidine kinase-negative mutant of herpes simplex virus-1 (dlsptk) that is attenuated for neurovirulence was tested as a possible treatment for gliomas. In cell culture, dlsptk killed two long-term human glioma lines and three short-term human glioma cell populations. In nude mice with implanted subcutaneous and subrenal U87 human gliomas, intraneoplastic inoculation of dlsptk caused growth inhibition. In nude mice with intracranial U87 gliomas, intraneoplastic inoculation of dlsptk prolonged survival. Genetically engineered viruses such as dlsptk merit further evaluation as novel antineoplastic agents.

  12. Mitogen-activated protein kinase-regulated AZI1 – an attractive candidate for genetic engineering

    PubMed Central

    Pitzschke, Andrea; Datta, Sneha; Persak, Helene

    2014-01-01

    Mitogen-activated protein kinases and their targets have been in the limelight of plant stress research. Signaling pathways mediating the responses to multiple stresses deserve particular attention. In a recent study, we reported AZI1, a member of the lipid transfer protein family, to play a role in MPK3-mediated responses to salt stress in Arabidopsis thaliana. MPK3 controls AZI1 at the transcriptional and posttranslational level. The AZI1 protein has several properties that make it very attractive for genetic engineering. A model of multi-level control of AZI1 by MPK3 is proposed, and strategies toward optimizing AZI1 protein properties are briefly discussed. PMID:24518841

  13. Predicting genetic engineering targets with Elementary Flux Mode Analysis: a review of four current methods.

    PubMed

    Ruckerbauer, David E; Jungreuthmayer, Christian; Zanghellini, Jürgen

    2015-12-25

    Elementary flux modes (EFMs) are a well-established tool in metabolic modeling. EFMs are minimal, feasible, steady state pathways through a metabolic network. They are used in various approaches to predict targets for genetic interventions in order to increase production of a molecule of interest via a host cell. Here we give an introduction to the concept of EFMs, present an overview of four methods which use EFMs in order to predict engineering targets and lastly use a toy model and a small-scale metabolic model to demonstrate and compare the capabilities of these methods. PMID:25917465

  14. Expanding the Scope of Site-Specific Recombinases for Genetic and Metabolic Engineering

    PubMed Central

    Gaj, Thomas; Sirk, Shannon J.; Barbas, Carlos F.

    2014-01-01

    Site-specific recombinases are tremendously valuable tools for basic research and genetic engineering. By promoting high-fidelity DNA modifications, site-specific recombination systems have empowered researchers with unprecedented control over diverse biological functions, enabling countless insights into cellular structure and function. The rigid target specificities of many sites-specific recombinases, however, have limited their adoption in fields that require highly flexible recognition abilities. As a result, intense effort has been directed toward altering the properties of site-specific recombination systems by protein engineering. Here, we review key developments in the rational design and directed molecular evolution of site-specific recombinases, highlighting the numerous applications of these enzymes across diverse fields of study. PMID:23982993

  15. Design and testing of a synthetic biology framework for genetic engineering of Corynebacterium glutamicum

    PubMed Central

    2012-01-01

    Background Synthetic biology approaches can make a significant contribution to the advance of metabolic engineering by reducing the development time of recombinant organisms. However, most of synthetic biology tools have been developed for Escherichia coli. Here we provide a platform for rapid engineering of C. glutamicum, a microorganism of great industrial interest. This bacteria, used for decades for the fermentative production of amino acids, has recently been developed as a host for the production of several economically important compounds including metabolites and recombinant proteins because of its higher capacity of secretion compared to traditional bacterial hosts like E. coli. Thus, the development of modern molecular platforms may significantly contribute to establish C. glutamicum as a robust and versatile microbial factory. Results A plasmid based platform named pTGR was created where all the genetic components are flanked by unique restriction sites to both facilitate the evaluation of regulatory sequences and the assembly of constructs for the expression of multiple genes. The approach was validated by using reporter genes to test promoters, ribosome binding sites, and for the assembly of dual gene operons and gene clusters containing two transcriptional units. Combinatorial assembly of promoter (tac, cspB and sod) and RBS (lacZ, cspB and sod) elements with different strengths conferred clear differential gene expression of two reporter genes, eGFP and mCherry, thus allowing transcriptional “fine-tuning”of multiple genes. In addition, the platform allowed the rapid assembly of operons and genes clusters for co-expression of heterologous genes, a feature that may assist metabolic pathway engineering. Conclusions We anticipate that the pTGR platform will contribute to explore the potential of novel parts to regulate gene expression, and to facilitate the assembly of genetic circuits for metabolic engineering of C. glutamicum. The standardization provided by this approach may provide a means to improve the productivity of biosynthetic pathways in microbial factories for the production of novel compounds. PMID:23134565

  16. Independent Neuronal Origin of Seizures and Behavioral Comorbidities in an Animal Model of a Severe Childhood Genetic Epileptic Encephalopathy

    PubMed Central

    Asinof, Samuel K.; Sukoff Rizzo, Stacey J.; Buckley, Alexandra R.; Beyer, Barbara J.; Letts, Verity A.; Frankel, Wayne N.; Boumil, Rebecca M.

    2015-01-01

    The childhood epileptic encephalopathies (EE’s) are seizure disorders that broadly impact development including cognitive, sensory and motor progress with severe consequences and comorbidities. Recently, mutations in DNM1 (dynamin 1) have been implicated in two EE syndromes, Lennox-Gastaut Syndrome and Infantile Spasms. Dnm1 encodes dynamin 1, a large multimeric GTPase necessary for activity-dependent membrane recycling in neurons, including synaptic vesicle endocytosis. Dnm1Ftfl or “fitful” mice carry a spontaneous mutation in the mouse ortholog of DNM1 and recapitulate many of the disease features associated with human DNM1 patients, providing a relevant disease model of human EE’s. In order to examine the cellular etiology of seizures and behavioral and neurological comorbidities, we engineered a conditional Dnm1Ftfl mouse model of DNM1 EE. Observations of Dnm1Ftfl/flox mice in combination with various neuronal subpopulation specific cre strains demonstrate unique seizure phenotypes and clear separation of major neurobehavioral comorbidities from severe seizures associated with the germline model. This demonstration of pleiotropy suggests that treating seizures per se may not prevent severe comorbidity observed in EE associated with dynamin-1 mutations, and is likely to have implications for other genetic forms of EE. PMID:26125563

  17. Formation mechanism of chalcogenide nanocrystals confined inside genetically engineered virus-like particles

    NASA Astrophysics Data System (ADS)

    Zhou, Ziyou; Bedwell, Gregory J.; Li, Rui; Prevelige, Peter E.; Gupta, Arunava

    2014-01-01

    Engineered virus-like particles (VLP) are attractive for fabricating nanostructured materials for applications in diverse areas such as catalysis, drug delivery, biomedicine, composites, etc. Basic understanding of the interaction between the inorganic guest and biomolecular host is thus important for the controlled synthesis of inorganic nanoparticles inside VLP and rational assembly of ordered VLP-based hierarchical nanostructures. We have investigated in detail the formation mechanism and growth kinetics of semiconducting nanocrystals confined inside genetically engineered bacteriophage P22 VLP using semiconducting CdS as a prototypical example. The selective nucleation and growth of CdS at the engineered sites is found to be uniform during the early stage, followed by a more stochastic growth process. Furthermore, kinetic studies reveal that the presence of an engineered biotemplate helps in significantly retarding the reaction rate. These findings provide guidance for the controlled synthesis of a wide range of other inorganic materials confined inside VLP, and are of practical importance for the rational design of VLP-based hierarchical nanostuctures.

  18. Formation mechanism of chalcogenide nanocrystals confined inside genetically engineered virus-like particles.

    PubMed

    Zhou, Ziyou; Bedwell, Gregory J; Li, Rui; Prevelige, Peter E; Gupta, Arunava

    2014-01-01

    Engineered virus-like particles (VLP) are attractive for fabricating nanostructured materials for applications in diverse areas such as catalysis, drug delivery, biomedicine, composites, etc. Basic understanding of the interaction between the inorganic guest and biomolecular host is thus important for the controlled synthesis of inorganic nanoparticles inside VLP and rational assembly of ordered VLP-based hierarchical nanostructures. We have investigated in detail the formation mechanism and growth kinetics of semiconducting nanocrystals confined inside genetically engineered bacteriophage P22 VLP using semiconducting CdS as a prototypical example. The selective nucleation and growth of CdS at the engineered sites is found to be uniform during the early stage, followed by a more stochastic growth process. Furthermore, kinetic studies reveal that the presence of an engineered biotemplate helps in significantly retarding the reaction rate. These findings provide guidance for the controlled synthesis of a wide range of other inorganic materials confined inside VLP, and are of practical importance for the rational design of VLP-based hierarchical nanostuctures. PMID:24452221

  19. Formation mechanism of chalcogenide nanocrystals confined inside genetically engineered virus-like particles

    PubMed Central

    Zhou, Ziyou; Bedwell, Gregory J.; Li, Rui; Prevelige, Peter E.; Gupta, Arunava

    2014-01-01

    Engineered virus-like particles (VLP) are attractive for fabricating nanostructured materials for applications in diverse areas such as catalysis, drug delivery, biomedicine, composites, etc. Basic understanding of the interaction between the inorganic guest and biomolecular host is thus important for the controlled synthesis of inorganic nanoparticles inside VLP and rational assembly of ordered VLP-based hierarchical nanostructures. We have investigated in detail the formation mechanism and growth kinetics of semiconducting nanocrystals confined inside genetically engineered bacteriophage P22 VLP using semiconducting CdS as a prototypical example. The selective nucleation and growth of CdS at the engineered sites is found to be uniform during the early stage, followed by a more stochastic growth process. Furthermore, kinetic studies reveal that the presence of an engineered biotemplate helps in significantly retarding the reaction rate. These findings provide guidance for the controlled synthesis of a wide range of other inorganic materials confined inside VLP, and are of practical importance for the rational design of VLP-based hierarchical nanostuctures. PMID:24452221

  20. The morality of socioscientific issues: Construal and resolution of genetic engineering dilemmas

    NASA Astrophysics Data System (ADS)

    Sadler, Troy D.; Zeidler, Dana L.

    2004-01-01

    The ability to negotiate and resolve socioscientific issues has been posited as integral components of scientific literacy. Although philosophers and science educators have argued that socioscientific issues inherently involve moral and ethical considerations, the ultimate arbiters of morality are individual decision-makers. This study explored the extent to which college students construe genetic engineering issues as moral problems. Twenty college students participated in interviews designed to elicit their ideas, reactions, and feelings regarding a series of gene therapy and cloning scenarios. Qualitative analyses revealed that moral considerations were significant influences on decision-making, indicating a tendency for students to construe genetic engineering issues as moral problems. Students engaged in moral reasoning based on utilitarian analyses of consequences as well as the application of principles. Issue construal was also influenced by affective features such as emotion and intuition. In addition to moral considerations, a series of other factors emerged as important dimensions of socioscientific decision-making. These factors included personal experiences, family biases, background knowledge, and the impact of popular culture. The implications for classroom science instruction and future research are discussed.

  1. Recent advances to improve fermentative butanol production: genetic engineering and fermentation technology.

    PubMed

    Zheng, Jin; Tashiro, Yukihiro; Wang, Qunhui; Sonomoto, Kenji

    2015-01-01

    Butanol has recently attracted attention as an alternative biofuel because of its various advantages over other biofuels. Many researchers have focused on butanol fermentation with renewable and sustainable resources, especially lignocellulosic materials, which has provided significant progress in butanol fermentation. However, there are still some drawbacks in butanol fermentation in terms of low butanol concentration and productivity, high cost of feedstock and product inhibition, which makes butanol fermentation less competitive than the production of other biofuels. These hurdles are being resolved in several ways. Genetic engineering is now available for improving butanol yield and butanol ratio through overexpression, knock out/down, and insertion of genes encoding key enzymes in the metabolic pathway of butanol fermentation. In addition, there are also many strategies to improve fermentation technology, such as multi-stage continuous fermentation, continuous fermentation integrated with immobilization and cell recycling, and the inclusion of additional organic acids or electron carriers to change metabolic flux. This review focuses on the most recent advances in butanol fermentation especially from the perspectives of genetic engineering and fermentation technology. PMID:25027723

  2. Improvements of tolerance to stress conditions by genetic engineering in Saccharomyces cerevisiae during ethanol production.

    PubMed

    Do?an, Ay?egül; Demirci, Selami; Aytekin, Ali Özhan; ?ahin, Fikrettin

    2014-09-01

    Saccharomyces cerevisiae, industrial yeast isolate, has been of great interest in recent years for fuel ethanol production. The ethanol yield and productivity depend on many inhibitory factors during the fermentation process such as temperature, ethanol, compounds released as the result of pretreatment procedures, and osmotic stress. An ideal strain should be able to grow under different stress conditions occurred at different fermentation steps. Development of tolerant yeast strains can be achieved by reprogramming pathways supporting the ethanol metabolism by regulating the energy balance and detoxicification processes. Complex gene interactions should be solved for an in-depth comprehension of the yeast stress tolerance mechanism. Genetic engineering as a powerful biotechnological tool is required to design new strategies for increasing the ethanol fermentation performance. Upregulation of stress tolerance genes by recombinant DNA technology can be a useful approach to overcome inhibitory situations. This review presents the application of several genetic engineering strategies to increase ethanol yield under different stress conditions including inhibitor tolerance, ethanol tolerance, thermotolerance, and osmotolerance. PMID:24908051

  3. Engineering modular and orthogonal genetic logic gates for robust digital-like synthetic biology

    PubMed Central

    Wang, Baojun; Kitney, Richard I; Joly, Nicolas; Buck, Martin

    2011-01-01

    Modular and orthogonal genetic logic gates are essential for building robust biologically based digital devices to customize cell signalling in synthetic biology. Here we constructed an orthogonal AND gate in Escherichia coli using a novel hetero-regulation module from Pseudomonas syringae. The device comprises two co-activating genes hrpR and hrpS controlled by separate promoter inputs, and a ?54-dependent hrpL promoter driving the output. The hrpL promoter is activated only when both genes are expressed, generating digital-like AND integration behaviour. The AND gate is demonstrated to be modular by applying new regulated promoters to the inputs, and connecting the output to a NOT gate module to produce a combinatorial NAND gate. The circuits were assembled using a parts-based engineering approach of quantitative characterization, modelling, followed by construction and testing. The results show that new genetic logic devices can be engineered predictably from novel native orthogonal biological control elements using quantitatively in-context characterized parts. PMID:22009040

  4. Lentivectors Encoding Immunosuppressive Proteins Genetically Engineer Pancreatic ? Cells to Correct Diabetes in Allogeneic Mice

    PubMed Central

    Kojaoghlanian, Tsoline; Joseph, Aviva; Follenzi, Antonia; Zheng, Jian Hua; Leiser, Margarita; Fleischer, Norman; Horwitz, Marshall S.; DiLorenzo, Teresa P.; Goldstein, Harris

    2010-01-01

    The effectiveness of genetic engineering with lentivectors to protect transplanted cells from allogeneic rejection was examined using, as a model, type 1 diabetes treatment with ? cell transplantation, whose widespread use has been limited by the requirement for sustained immunosuppressive treatment to prevent graft rejection. We examined whether lentivectors expressing select immunosuppressive proteins encoded by the adenoviral genome early region 3 (AdE3) would protect transplanted ? cells from an alloimmune attack. The insulin-producing ? cell line ?TC-tet (C3HeB/FeJ-derived) was transduced with lentiviruses encoding the AdE3 proteins gp19K and RID?/?. The efficiency of lentiviral transduction of ?TC-tet cells exceeded 85%. Lentivector expression of gp19K decreased surface class I MHC expression by over 90%, while RID?/? expression inhibited cytokine-induced Fas upregulation by over 75%. ?TC-tet cells transduced with gp19K and RID?/? lentivectors, but not with a control lentivector, provided prolonged correction of hyperglycemia after transplantation into diabetic BALB/c SCID mice reconstituted with allogeneic immune effector cells or into diabetic allogeneic BALB/c mice. Thus, genetic engineering of ? cells using gp19K and RID?/? expressing lentiviral vectors may provide an alternative that has the potential to eliminate or reduce treatment with the potent immunosuppressive agents currently necessary for prolonged engraftment with transplanted islets. PMID:19112449

  5. Induction of erythropoiesis using human vascular networks genetically engineered for controlled erythropoietin release

    PubMed Central

    Lin, Ruei-Zeng; Dreyzin, Alexandra; Aamodt, Kristie; Li, Dan; Jaminet, Shou-Ching S.; Dudley, Andrew C.

    2011-01-01

    For decades, autologous ex vivo gene therapy has been postulated as a potential alternative to parenteral administration of recombinant proteins. However, achieving effective cellular engraftment of previously retrieved patient cells is challenging. Recently, our ability to engineer vasculature in vivo has allowed for the introduction of instructions into tissues by genetically modifying the vascular cells that build these blood vessels. In the present study, we genetically engineered human blood–derived endothelial colony-forming cells (ECFCs) to express erythropoietin (EPO) under the control of a tetracycline-regulated system, and generated subcutaneous vascular networks capable of systemic EPO release in immunodeficient mice. These ECFC-lined vascular networks formed functional anastomoses with the mouse vasculature, allowing direct delivery of recombinant human EPO into the bloodstream. After activation of EPO expression, erythropoiesis was induced in both normal and anemic mice, a process that was completely reversible. This approach could relieve patients from frequent EPO injections, reducing the medical costs associated with the management of anemia. We propose this ECFC-based gene-delivery strategy as a viable alternative technology when routine administration of recombinant proteins is needed. PMID:21937702

  6. Genetically engineered mice demonstrate that adenosine deaminase is essential for early postimplantation development.

    PubMed

    Blackburn, M R; Knudsen, T B; Kellems, R E

    1997-08-01

    Adenosine deaminase (ADA) is an essential enzyme of purine metabolism that is enriched at the maternal-fetal interface of mice throughout postimplantation development. During early postimplantation stages Ada is highly expressed in both maternally derived decidual cells and zygotically derived trophoblast cells. For the current study we utilized genetically modified mice to delineate the relative contribution and importance of decidual and trophoblast ADA at the maternal-fetal interface. In females genetically engineered to lack decidual ADA a striking pattern of expression was revealed in giant trophoblast cells that surround the early postimplantation embryo. Embryos within gestation sites lacking both decidual and trophoblast ADA died during the early postimplantation period, whereas expression in trophoblast cells alone was sufficient for survival through this period. Severe disturbances in purine metabolism were observed in gestation sites lacking decidual ADA, including the accumulation of the potentially toxic ADA substrates adenosine and 2'-deoxyadenosine. These experiments provide genetic evidence that Ada expression at the maternal-fetal interface is essential for early postimplantation development in mice. PMID:9272950

  7. How can plant genetic engineering contribute to cost-effective fish vaccine development for promoting sustainable aquaculture?

    PubMed

    Clarke, Jihong Liu; Waheed, Mohammad Tahir; Lössl, Andreas G; Martinussen, Inger; Daniell, Henry

    2013-09-01

    Aquaculture, the fastest growing food-producing sector, now accounts for nearly 50 % of the world's food fish (FAO in The state of world fisheries and aquaculture. FAO, Rome, 2010). The global aquaculture production of food fish reached 62.7 million tonnes in 2011 and is continuously increasing with an estimated production of food fish of 66.5 million tonnes in 2012 (a 9.4 % increase in 1 year, FAO, www.fao.org/fishery/topic/16140 ). Aquaculture is not only important for sustainable protein-based food fish production but also for the aquaculture industry and economy worldwide. Disease prevention is the key issue to maintain a sustainable development of aquaculture. Widespread use of antibiotics in aquaculture has led to the development of antibiotic-resistant bacteria and the accumulation of antibiotics in the environment, resulting in water and soil pollution. Thus, vaccination is the most effective and environmentally-friendly approach to combat diseases in aquaculture to manage fish health. Furthermore, when compared to >760 vaccines against human diseases, there are only about 30 fish vaccines commercially available, suggesting the urgent need for development and cost-effective production of fish vaccines for managing fish health, especially in the fast growing fish farming in Asia where profit is minimal and therefore given high priority. Plant genetic engineering has made significant contributions to production of biotech crops for food, feed, valuable recombinant proteins etc. in the past three decades. The use of plants for vaccine production offers several advantages such as low cost, safety and easy scaling up. To date a large number of plant-derived vaccines, antibodies and therapeutic proteins have been produced for human health, of which a few have been made commercially available. However, the development of animal vaccines in plants, especially fish vaccines by genetic engineering, has not yet been addressed. Therefore, there is a need to exploit plant biotechnology for cost effective fish vaccine development in plants, in particular, edible crops for oral fish vaccines. This review provides insight into (1) the current status of fish vaccine and vaccination in aquaculture, (2) plant biotechnology and edible crops for fish vaccines for oral administration, (3) regulatory constraints and (4) conclusions and future perspectives. PMID:23729352

  8. Targeted genetic manipulations of neuronal subtypes using promoter-specific combinatorial AAVs in wild-type animals

    PubMed Central

    Gompf, Heinrich S.; Budygin, Evgeny A.; Fuller, Patrick M.; Bass, Caroline E.

    2015-01-01

    Techniques to genetically manipulate the activity of defined neuronal subpopulations have been useful in elucidating function, however applicability to translational research beyond transgenic mice is limited. Subtype targeted transgene expression can be achieved using specific promoters, but often currently available promoters are either too large to package into many vectors, in particular adeno-associated virus (AAV), or do not drive expression at levels sufficient to alter behavior. To permit neuron subtype specific gene expression in wildtype animals, we developed a combinatorial AAV targeting system that drives, in combination, subtype specific Cre-recombinase expression with a strong but non-specific Cre-conditional transgene. Using this system we demonstrate that the tyrosine hydroxylase promoter (TH-Cre-AAV) restricted expression of channelrhodopsin-2 (EF1?-DIO-ChR2-EYFP-AAV) to the rat ventral tegmental area (VTA), or an activating DREADD (hSyn-DIO-hM3Dq-mCherry-AAV) to? the? rat? locus? coeruleus? (LC). High expression levels were achieved in both regions. Immunohistochemistry (IHC) showed the majority of ChR2+ neurons (>93%) colocalized with TH in the VTA, and optical stimulation evoked striatal dopamine release. Activation of TH neurons in the LC produced sustained EEG and behavioral arousal. TH-specific hM3Dq expression in the LC was further compared with: (1) a Cre construct driven by a strong but non-specific promoter (non-targeting); and (2) a retrogradely-transported WGA-Cre delivery mechanism (targeting a specific projection). IHC revealed that the area of c-fos activation after CNO treatment in the LC and peri-LC neurons appeared proportional to the resulting increase in wakefulness (non-targeted > targeted > ACC to LC projection restricted). Our dual AAV targeting system effectively overcomes the large size and weak activity barrier prevalent with many subtype specific promoters by functionally separating subtype specificity from promoter strength. PMID:26190981

  9. Genetic engineering: Baculoviruses as expression vectors. (Latest citations from the Life Sciences Collection data base). Published Search

    SciTech Connect

    Not Available

    1992-05-01

    The bibliography contains citations concerning the use of baculoviruses in genetic engineering. Baculoviruses produce large quantities of a specific gene. Topics include genetic replication, expression of selected genes in host cells, and protein expression using baculoviruses. Baculovirus introduction into mammals causing antibody expression is considered, and implications on vaccine programs are briefly discussed. (Contains a minimum of 112 citations and includes a subject term index and title list.)

  10. Mice fed on a diet enriched with genetically engineered multivitamin corn show no sub-acute toxic effects and no sub-chronic toxicity.

    PubMed

    Arjó, Gemma; Capell, Teresa; Matias-Guiu, Xavier; Zhu, Changfu; Christou, Paul; Piñol, Carme

    2012-12-01

    Multivitamin corn is a novel genetically engineered variety that simultaneously produces high levels of ?-carotene, ascorbate and folate, and therefore has the potential to address simultaneously multiple micronutrient deficiencies caused by the lack of vitamins A, B9 and C in developing country populations. As part of the development process for genetically engineered crops and following European Food Safety Authority (EFSA) recommendations, multivitamin corn must be tested in whole food/feed sub-chronic animal feeding studies to ensure there are no adverse effects, and potential allergens must be identified. We carried out a 28-day toxicity assessment in mice, which showed no short-term sub-acute evidence of diet-related adverse health effects and no difference in clinical markers (food consumption, body weight, organ/tissue weight, haematological and biochemical blood parameters and histopathology) compared to mice fed on a control diet. A subsequent 90-day sub-chronic feeding study again showed no indications of toxicity compared to mice fed on control diets. Our data confirm that diets enriched with multivitamin corn have no adverse effects on mice, do not induce any clinical signs of toxicity and do not contain known allergens. PMID:22928600

  11. Draft genome sequence of Xanthomonas axonopodis pv. glycines 8ra possessing transcription activator-like effectors used for genetic engineering.

    PubMed

    Lee, Ju-Hoon; Shin, Hakdong; Park, Hye-Jee; Ryu, Sangryeol; Han, Sang-Wook

    2014-06-10

    Xanthomonas axonopodis pv. glycines 8ra is a causal agent of bacterial pustule disease in soybean. This bacterium possesses transcription activator-like (TAL) effectors which are useful for genetic/protein engineering applications in higher organisms including plants and humans. Here, we report that the draft genome sequence consists of 5,337,885-bp double-stranded DNA encoding 4674 open reading frames (ORFs) in 13 different contigs. This genome sequence would be useful in applications of TAL effectors in genetic engineering and in elucidating virulence factors against plants. PMID:24657734

  12. Genetic engineering of a Ca(2+) dependent chemical switch into the linear biomotor kinesin.

    PubMed

    Konishi, Kaoru; Uyeda, Taro Q P; Kubo, Tai

    2006-06-26

    Kinesin is a linear motor protein driven by energy released by ATP hydrolysis. In the present work, we genetically installed an M13 peptide sequence into Loop 12 of kinesin, which is one of the major microtubule binding regions of the protein. Because the M13 sequence has high affinity for Ca(2+)-calmodulin, the association of the engineered kinesin with microtubules showed a steep Ca(2+)-dependency in ATPase activity at Ca(2+) concentrations of pCa 6.5-8. The calmodulin-binding domain of plant kinesin-like calmodulin-binding protein is also known to confer Ca(2+)-calmodulin regulation to kinesins. Unlike this plant kinesin, however, our novel engineered kinesin achieves this regulation while maintaining the interaction between kinesin and microtubules. The engineered kinesin is switched on/off reversibly by an external signal (i.e., Ca(2+)-calmodulin) and, thus, can be used as a model system for a bio/nano-actuator. PMID:16753152

  13. Production of Engineered Fabrics Using Artificial Neural Network-Genetic Algorithm Hybrid Model

    NASA Astrophysics Data System (ADS)

    Mitra, Ashis; Majumdar, Prabal Kumar; Banerjee, Debamalya

    2014-11-01

    The process of fabric engineering which is generally practised in most of the textile mills is very complicated, repetitive, tedious and time consuming. To eliminate this trial and error approach, a new approach of fabric engineering has been attempted in this work. Data sets of construction parameters [comprising of ends per inch, picks per inch, warp count and weft count] and three fabric properties (namely drape coefficient, air permeability and thermal resistance) of 25 handloom cotton fabrics have been used. The weights and biases of three artificial neural network (ANN) models developed for the prediction of drape coefficient, air permeability and thermal resistance were used to formulate the fitness or objective function and constraints of the optimization problem. The optimization problem was solved using genetic algorithm (GA). In both the fabrics which were attempted for engineering, the target and simulated fabric properties were very close. The GA was able to search the optimum set of fabric construction parameters with reasonably good accuracy except in case of EPI. However, the overall result is encouraging and can be improved further by using larger data sets of handloom fabrics by hybrid ANN-GA model.

  14. A Pseudomonas putida Strain Genetically Engineered for 1,2,3-Trichloropropane Bioremediation

    PubMed Central

    Samin, Ghufrana; Pavlova, Martina; Arif, M. Irfan; Postema, Christiaan P.; Damborsky, Jiri

    2014-01-01

    1,2,3-Trichloropropane (TCP) is a toxic compound that is recalcitrant to biodegradation in the environment. Attempts to isolate TCP-degrading organisms using enrichment cultivation have failed. A potential biodegradation pathway starts with hydrolytic dehalogenation to 2,3-dichloro-1-propanol (DCP), followed by oxidative metabolism. To obtain a practically applicable TCP-degrading organism, we introduced an engineered haloalkane dehalogenase with improved TCP degradation activity into the DCP-degrading bacterium Pseudomonas putida MC4. For this purpose, the dehalogenase gene (dhaA31) was cloned behind the constitutive dhlA promoter and was introduced into the genome of strain MC4 using a transposon delivery system. The transposon-located antibiotic resistance marker was subsequently removed using a resolvase step. Growth of the resulting engineered bacterium, P. putida MC4-5222, on TCP was indeed observed, and all organic chlorine was released as chloride. A packed-bed reactor with immobilized cells of strain MC4-5222 degraded >95% of influent TCP (0.33 mM) under continuous-flow conditions, with stoichiometric release of inorganic chloride. The results demonstrate the successful use of a laboratory-evolved dehalogenase and genetic engineering to produce an effective, plasmid-free, and stable whole-cell biocatalyst for the aerobic bioremediation of a recalcitrant chlorinated hydrocarbon. PMID:24973068

  15. Practical animal breeding as the key to an integrated view of genetics, eugenics and evolutionary theory: Arend L. Hagedoorn (1885-1953).

    PubMed

    Theunissen, Bert

    2014-06-01

    In the history of genetics Arend Hagedoorn (1885-1953) is mainly known for the 'Hagedoorn effect', which states that part of the changes in variability that populations undergo over time are due to chance effects. Leaving this contribution aside, Hagedoorn's work has received scarcely any attention from historians. This is mainly due to the fact that Hagedoorn was an expert in animal breeding, a field that historians have only recently begun to explore. His work provides an example of how a prominent geneticist envisaged animal breeding to be reformed by the new science of heredity. Hagedoorn, a pupil of Hugo de Vries, tried to integrate his insights as a Mendelian geneticist and an animal breeding expert in a unified view of heredity, eugenics and evolution. In this paper I aim to elucidate how these fields were connected in Hagedoorn's work. PMID:24747808

  16. Multidisciplinary Design Optimization for Aeropropulsion Engines and Solid Modeling/Animation via the Integrated Forced Methods

    NASA Technical Reports Server (NTRS)

    2004-01-01

    The grant closure report is organized in the following four chapters: Chapter describes the two research areas Design optimization and Solid mechanics. Ten journal publications are listed in the second chapter. Five highlights is the subject matter of chapter three. CHAPTER 1. The Design Optimization Test Bed CometBoards. CHAPTER 2. Solid Mechanics: Integrated Force Method of Analysis. CHAPTER 3. Five Highlights: Neural Network and Regression Methods Demonstrated in the Design Optimization of a Subsonic Aircraft. Neural Network and Regression Soft Model Extended for PX-300 Aircraft Engine. Engine with Regression and Neural Network Approximators Designed. Cascade Optimization Strategy with Neural network and Regression Approximations Demonstrated on a Preliminary Aircraft Engine Design. Neural Network and Regression Approximations Used in Aircraft Design.

  17. How Not to Be a BlackBox: Evolution and GeneticEngineering of HighLevel Behaviours \\Lambda Swiss Federal Institute of Technology (EPFL)

    E-print Network

    Fernandez, Thomas

    How Not to Be a Black­Box: Evolution and Genetic­Engineering of High­Level Behaviours \\Lambda Ik thalmann@lig.di.epfl.ch Abstract In spite of many success stories in various do­ mains, Genetic Algorithm and Genetic Program­ ming still suffer from some significant pitfalls. Those evolved programs often lack

  18. How Not to Be a Black-Box: Evolution and Genetic-Engineering of High-Level Behaviours Swiss Federal Institute of Technology (EPFL)

    E-print Network

    Fernandez, Thomas

    How Not to Be a Black-Box: Evolution and Genetic-Engineering of High-Level Behaviours Ik Soo Lim thalmann@lig.di.epfl.ch Abstract In spite of many success stories in various do- mains, Genetic Algorithm and Genetic Program- ming still suffer from some significant pitfalls. Those evolved programs often lack

  19. Intelligent Computing in Engineering -ICE08 Resolving Incorrect Occlusion in Augmented Reality Animations

    E-print Network

    Kamat, Vineet R.

    Intelligent Computing in Engineering - ICE08 24 Resolving Incorrect Occlusion in Augmented Reality Arbor, MI 48109, USA abehzada@umich.edu Abstract. Augmented Reality (AR) visualization offers operations. Following this approach, Augmented Reality (AR) is used to create mixed views of real existing

  20. Automated Generation of Dynamic Walk-Through Animations of Simulated Engineering Operations in Augmented Reality Environments

    E-print Network

    Kamat, Vineet R.

    in Augmented Reality Environments Amir H. Behzadan Department of Construction Management and Civil Engineering lifecycle. This paper presents ARVISCOPE, an Augmented Reality (AR) visualization tool capable of creating in recent years is Augmented Reality (AR). The main difference between an AR-based and a VR

  1. Biochemical and genetic engineering of diatoms for polyunsaturated fatty acid biosynthesis.

    PubMed

    Li, Hong-Ye; Lu, Yang; Zheng, Jian-Wei; Yang, Wei-Dong; Liu, Jie-Sheng

    2014-01-01

    The role of diatoms as a source of bioactive compounds has been recently explored. Diatom cells store a high amount of fatty acids, especially certain polyunsaturated fatty acids (PUFAs). However, many aspects of diatom metabolism and the production of PUFAs remain unclear. This review describes a number of technical strategies, such as modulation of environmental factors (temperature, light, chemical composition of culture medium) and culture methods, to influence the content of PUFAs in diatoms. Genetic engineering, a newly emerging field, also plays an important role in controlling the synthesis of fatty acids in marine microalgae. Several key points in the biosynthetic pathway of PUFAs in diatoms as well as recent progresses are also a critical part and are summarized here. PMID:24402175

  2. Biochemical and Genetic Engineering of Diatoms for Polyunsaturated Fatty Acid Biosynthesis

    PubMed Central

    Li, Hong-Ye; Lu, Yang; Zheng, Jian-Wei; Yang, Wei-Dong; Liu, Jie-Sheng

    2014-01-01

    The role of diatoms as a source of bioactive compounds has been recently explored. Diatom cells store a high amount of fatty acids, especially certain polyunsaturated fatty acids (PUFAs). However, many aspects of diatom metabolism and the production of PUFAs remain unclear. This review describes a number of technical strategies, such as modulation of environmental factors (temperature, light, chemical composition of culture medium) and culture methods, to influence the content of PUFAs in diatoms. Genetic engineering, a newly emerging field, also plays an important role in controlling the synthesis of fatty acids in marine microalgae. Several key points in the biosynthetic pathway of PUFAs in diatoms as well as recent progresses are also a critical part and are summarized here. PMID:24402175

  3. Over production of lignocellulosic enzymes of Coriolus versicolor by genetic engineering methodology. Final report

    SciTech Connect

    Williams, A.L.

    1998-07-01

    The project seeks to understand the biological and chemical processes involved in the secretion of the enzyme polyphenol oxidase (PPO) by the hyphae, the basic unit of the filamentous fungus Coriolus versicolor. These studies are made to determine rational strategies for enhanced secretion of PPO, both with the use of recombinant DNA techniques and without. This effort focuses on recombinant DNA techniques to enhance enzyme production. The major thrust of this project was two-fold: to mass produce C. versicolor tyrosinase (polyphenol oxidase) by genetic engineering as well as cultural manipulations; and to utilize PPO as a biocatalyst in the processing of lignocellulose as a renewable energy resource. In this study, the assessment of genomic and cDNA recombinant clones with regards to the overproduction of PPO continued. Further, immunocytochemical techniques were employed to assess the mechanism(s) involved in the secretion of PPO by the hyphae. Also, factors influencing PPO secretion were examined.

  4. The function of herpes simplex virus genes: a primer for genetic engineering of novel vectors.

    PubMed Central

    Roizman, B

    1996-01-01

    Herpes simplex virus vectors are being developed for delivery and expression of human genes to the central nervous system, selective destruction of cancer cells, and as carriers for genes encoding antigens that induce protective immunity against infectious agents. Vectors constructed to meet these objectives must differ from wild-type virus with respect to host range, reactivation from latency, and expression of viral genes. The vectors currently being developed are (i) helper free amplicons, (ii) replication defective viruses, and (iii) genetically engineered replication competent viruses with restricted host range. Whereas the former two types of vectors require stable, continuous cell lines expressing viral genes for their replication, the replication competent viruses will replicate on approved primary human cell strains. PMID:8876131

  5. Heritable Multiplex Genetic Engineering in Rats Using CRISPR/Cas9

    PubMed Central

    Zhang, Xu; Lu, Yingdong; Chen, Wei; Ma, Jing; Huang, Xingxu; Zhang, Lianfeng

    2014-01-01

    The CRISPR/Cas9 system has been proven to be an efficient gene-editing tool for genome modification of cells and organisms. Multiplex genetic engineering in rat holds a bright future for the study of complex disease. Here, we show that this system enables the simultaneous disruption of four genes (ApoE, B2m, Prf1, and Prkdc) in rats in one-step, by co-injection of Cas9 mRNA and sgRNAs into fertilized eggs. We further observed the gene modifications are germline transmittable, and confirmed the off-target mutagenesis and mosaicism are rarely detected by comprehensive analysis. Thus, the CRISPR/Cas9 system makes it possible to efficiently and reliably generate gene knock-out rats. PMID:24598943

  6. Can we build it better? Using BAC genetics to engineer more effective cytomegalovirus vaccines

    PubMed Central

    Schleiss, Mark R.

    2010-01-01

    The magnitude and durability of immunity to human cytomegalovirus (HCMV) following natural infection is compromised by the presence of immune modulation genes that appear to promote evasion of host clearance mechanisms. Since immunity to HCMV offers limited protection, rational design of effective vaccines has been challenging. In this issue of the JCI, Slavuljica and colleagues employ techniques to genetically modify the highly related mouse CMV (MCMV), in the process generating a virus that was rapidly cleared by NK cells. The virus functioned as a safe and highly effective vaccine. Demonstration of the ability to engineer a safe and highly effective live virus vaccine in a relevant rodent model of CMV infection may open the door to clinical trials of safer and more immunogenic HCMV vaccines. PMID:21099107

  7. Can we build it better? Using BAC genetics to engineer more effective cytomegalovirus vaccines.

    PubMed

    Schleiss, Mark R

    2010-12-01

    The magnitude and durability of immunity to human cytomegalovirus (HCMV) following natural infection is compromised by the presence of immune modulation genes that appear to promote evasion of host clearance mechanisms. Since immunity to HCMV offers limited protection, rational design of effective vaccines has been challenging. In this issue of the JCI, Slavuljica and colleagues employ techniques to genetically modify the highly related mouse CMV (MCMV), in the process generating a virus that was rapidly cleared by NK cells. The virus functioned as a safe and highly effective vaccine. Demonstration of the ability to engineer a safe and highly effective live virus vaccine in a relevant rodent model of CMV infection may open the door to clinical trials of safer and more immunogenic HCMV vaccines. PMID:21099107

  8. Stem cells in genetically-engineered mouse models of prostate cancer.

    PubMed

    Shibata, Maho; Shen, Michael M

    2015-12-01

    The cancer stem cell model proposes that tumors have a hierarchical organization in which tumorigenic cells give rise to non-tumorigenic cells, with only a subset of stem-like cells able to propagate the tumor. In the case of prostate cancer, recent analyses of genetically engineered mouse (GEM) models have provided evidence supporting the existence of cancer stem cells in vivo. These studies suggest that cancer stem cells capable of tumor propagation exist at various stages of tumor progression from prostatic intraepithelial neoplasia (PIN) to advanced metastatic and castration-resistant disease. However, studies of stem cells in prostate cancer have been limited by available approaches for evaluating their functional properties in cell culture and transplantation assays. Given the role of the tumor microenvironment and the putative cancer stem cell niche, future studies using GEM models to analyze cancer stem cells in their native tissue microenvironment are likely to be highly informative. PMID:26341780

  9. Genetically Engineered Mice as Experimental Tools to Dissect the Critical Events in Breast Cancer

    PubMed Central

    Menezes, Mitchell E.; Das, Swadesh K.; Emdad, Luni; Windle, Jolene J.; Wang, Xiang-Yang; Sarkar, Devanand; Fisher, Paul B.

    2015-01-01

    Elucidating the mechanism of pathogenesis of breast cancer has greatly benefited from breakthrough advances in both genetically engineered mouse (GEM) models and xenograft transplantation technologies. The vast array of breast cancer mouse models currently available is testimony to the complexity of mammary tumorigenesis and attempts by investigators to accurately portray the heterogeneity and intricacies of this disease. Distinct molecular changes that drive various aspects of tumorigenesis, such as alterations in tumor cell proliferation and apoptosis, invasion and metastasis, angiogenesis, and drug resistance have been evaluated using the currently available GEM breast cancer models. GEM breast cancer models are also being exploited to evaluate and validate the efficacy of novel therapeutics, vaccines, and imaging modalities for potential use in the clinic. This review provides a synopsis of the various GEM models that are expanding our knowledge of the nuances of breast cancer development and progression and can be instrumental in the development of novel prevention and therapeutic approaches for this disease. PMID:24889535

  10. Biochemical, genetic, and metabolic engineering strategies to enhance coproduction of 1-propanol and ethanol in engineered Escherichia coli.

    PubMed

    Srirangan, Kajan; Liu, Xuejia; Westbrook, Adam; Akawi, Lamees; Pyne, Michael E; Moo-Young, Murray; Chou, C Perry

    2014-11-01

    We recently reported the heterologous production of 1-propanol in Escherichia coli via extended dissimilation of succinate under anaerobic conditions through expression of the endogenous sleeping beauty mutase (Sbm) operon. In the present work, we demonstrate high-level coproduction of 1-propanol and ethanol by developing novel engineered E. coli strains with effective cultivation strategies. Various biochemical, genetic, metabolic, and physiological factors affecting relative levels of acidogenesis and solventogenesis during anaerobic fermentation were investigated. In particular, CPC-PrOH3, a plasmid-free propanogenic E. coli strain derived by activating the Sbm operon on the genome, showed high levels of solventogenesis accounting for up to 85 % of dissimilated carbon. Anaerobic fed-batch cultivation of CPC-PrOH3 with glycerol as the major carbon source produced high titers of nearly 7 g/L 1-propanol and 31 g/L ethanol, implying its potential industrial applicability. The activated Sbm pathway served as an ancillary channel for consuming reducing equivalents upon anaerobic dissimilation of glycerol, resulting in an enhanced glycerol dissimilation and a major metabolic shift from acidogenesis to solventogenesis. PMID:25301579

  11. Evaluating Learning and Attitudes on Tissue Engineering: A Study of Children Viewing Animated Digital Dome Shows Detailing the Biomedicine of Tissue Engineering

    PubMed Central

    Wilson, Anna C.; Gonzalez, Laura L.

    2012-01-01

    Informal science education creates opportunities for the general public to learn about complex health and science topics. Tissue engineering is a fast-growing field of medical science that combines advanced chemistries to create synthetic scaffolds, stem cells, and growth factors that individually or in combination can support the bodies own healing powers to remedy a range of maladies. Health literacy about this topic is increasingly important as our population ages and as treatments become more technologically advanced. We are using a science center planetarium as a projection space to engage and educate the public about the science and biomedical research that supports tissue engineering. The purpose of this study was to test the effectiveness of the films that we have produced for part of the science center planetarium demographic, specifically children ranging in age from 7 to 16 years. A two-group pre- and post-test design was used to compare children's learning and attitude changes in response to the two versions of the film. One version uses traditional voice-over narration; the other version uses dialog between two animated characters. The results of this study indicate that children demonstrated increases in knowledge of the topic with either film format, but preferred the animated character version. The percentage change in children's scores on the knowledge questions given before and after viewing the show exhibited an improvement from 23% correct to 61% correct on average. In addition, many of the things that the children reported liking were part of the design process of the art–science collaboration. Other results indicated that before viewing the shows 77% of the children had not even heard about tissue engineering and only 17% indicated that they were very interested in it, whereas after viewing the shows, 95% indicated that tissue engineering was a good idea. We also find that after viewing the show, 71% of the children reported that the show made them think, 75% enjoyed it, and 89% felt that they learned something. We discuss the potential impact the films might have on public knowledge, health literacy, and attitudes toward the science of tissue engineering. PMID:21943030

  12. Evaluating learning and attitudes on tissue engineering: a study of children viewing animated digital dome shows detailing the biomedicine of tissue engineering.

    PubMed

    Wilson, Anna C; Gonzalez, Laura L; Pollock, John A

    2012-03-01

    Informal science education creates opportunities for the general public to learn about complex health and science topics. Tissue engineering is a fast-growing field of medical science that combines advanced chemistries to create synthetic scaffolds, stem cells, and growth factors that individually or in combination can support the bodies own healing powers to remedy a range of maladies. Health literacy about this topic is increasingly important as our population ages and as treatments become more technologically advanced. We are using a science center planetarium as a projection space to engage and educate the public about the science and biomedical research that supports tissue engineering. The purpose of this study was to test the effectiveness of the films that we have produced for part of the science center planetarium demographic, specifically children ranging in age from 7 to 16 years. A two-group pre- and post-test design was used to compare children's learning and attitude changes in response to the two versions of the film. One version uses traditional voice-over narration; the other version uses dialog between two animated characters. The results of this study indicate that children demonstrated increases in knowledge of the topic with either film format, but preferred the animated character version. The percentage change in children's scores on the knowledge questions given before and after viewing the show exhibited an improvement from 23% correct to 61% correct on average. In addition, many of the things that the children reported liking were part of the design process of the art-science collaboration. Other results indicated that before viewing the shows 77% of the children had not even heard about tissue engineering and only 17% indicated that they were very interested in it, whereas after viewing the shows, 95% indicated that tissue engineering was a good idea. We also find that after viewing the show, 71% of the children reported that the show made them think, 75% enjoyed it, and 89% felt that they learned something. We discuss the potential impact the films might have on public knowledge, health literacy, and attitudes toward the science of tissue engineering. PMID:21943030

  13. Development of New Modular Genetic Tools for Engineering the Halophilic Archaeon Halobacterium salinarum

    PubMed Central

    Silva-Rocha, Rafael; Pontelli, Marjorie Cornejo; Furtado, Gilvan Pessoa; Zaramela, Livia Soares; Koide, Tie

    2015-01-01

    Our ability to genetically manipulate living organisms is usually constrained by the efficiency of the genetic tools available for the system of interest. In this report, we present the design, construction and characterization of a set of four new modular vectors, the pHsal series, for engineering Halobacterium salinarum, a model halophilic archaeon widely used in systems biology studies. The pHsal shuttle vectors are organized in four modules: (i) the E. coli’s specific part, containing a ColE1 origin of replication and an ampicillin resistance marker, (ii) the resistance marker and (iii) the replication origin, which are specific to H. salinarum and (iv) the cargo, which will carry a sequence of interest cloned in a multiple cloning site, flanked by universal M13 primers. Each module was constructed using only minimal functional elements that were sequence edited to eliminate redundant restriction sites useful for cloning. This optimization process allowed the construction of vectors with reduced sizes compared to currently available platforms and expanded multiple cloning sites. Additionally, the strong constitutive promoter of the fer2 gene was sequence optimized and incorporated into the platform to allow high-level expression of heterologous genes in H. salinarum. The system also includes a new minimal suicide vector for the generation of knockouts and/or the incorporation of chromosomal tags, as well as a vector for promoter probing using a GFP gene as reporter. This new set of optimized vectors should strongly facilitate the engineering of H. salinarum and similar strategies could be implemented for other archaea. PMID:26061363

  14. Development of New Modular Genetic Tools for Engineering the Halophilic Archaeon Halobacterium salinarum.

    PubMed

    Silva-Rocha, Rafael; Pontelli, Marjorie Cornejo; Furtado, Gilvan Pessoa; Zaramela, Livia Soares; Koide, Tie

    2015-01-01

    Our ability to genetically manipulate living organisms is usually constrained by the efficiency of the genetic tools available for the system of interest. In this report, we present the design, construction and characterization of a set of four new modular vectors, the pHsal series, for engineering Halobacterium salinarum, a model halophilic archaeon widely used in systems biology studies. The pHsal shuttle vectors are organized in four modules: (i) the E. coli's specific part, containing a ColE1 origin of replication and an ampicillin resistance marker, (ii) the resistance marker and (iii) the replication origin, which are specific to H. salinarum and (iv) the cargo, which will carry a sequence of interest cloned in a multiple cloning site, flanked by universal M13 primers. Each module was constructed using only minimal functional elements that were sequence edited to eliminate redundant restriction sites useful for cloning. This optimization process allowed the construction of vectors with reduced sizes compared to currently available platforms and expanded multiple cloning sites. Additionally, the strong constitutive promoter of the fer2 gene was sequence optimized and incorporated into the platform to allow high-level expression of heterologous genes in H. salinarum. The system also includes a new minimal suicide vector for the generation of knockouts and/or the incorporation of chromosomal tags, as well as a vector for promoter probing using a GFP gene as reporter. This new set of optimized vectors should strongly facilitate the engineering of H. salinarum and similar strategies could be implemented for other archaea. PMID:26061363

  15. Examining strategies to facilitate vitamin B1 biofortification of plants by genetic engineering

    PubMed Central

    Pourcel, Lucille; Moulin, Michael; Fitzpatrick, Teresa B.

    2013-01-01

    Thiamin (vitamin B1) is made by plants and microorganisms but is an essential micronutrient in the human diet. All organisms require it as a cofactor in its form as thiamin pyrophosphate (TPP) for the activity of key enzymes of central metabolism. In humans, deficiency is widespread particularly in populations where polished rice is a major component of the diet. Considerable progress has been made on the elucidation of the biosynthesis pathway within the last few years enabling concrete strategies for biofortification purposes to be devised, with a particular focus here on genetic engineering. Furthermore, the vitamin has been shown to play a role in both abiotic and biotic stress responses. The precursors for de novo biosynthesis of thiamin differ between microorganisms and plants. Bacteria use intermediates derived from purine and isoprenoid biosynthesis, whereas the pathway in yeast involves the use of compounds from the vitamin B3 and B6 groups. Plants on the other hand use a combination of the bacterial and yeast pathways and there is subcellular partitioning of the biosynthesis steps. Specifically, thiamin biosynthesis occurs in the chloroplast of plants through the separate formation of the pyrimidine and thiazole moieties, which are then coupled to form thiamin monophosphate (TMP). Phosphorylation of thiamin to form TPP occurs in the cytosol. Therefore, thiamin (or TMP) must be exported from the chloroplast to the cytosol for the latter step to be executed. The regulation of biosynthesis is mediated through riboswitches, where binding of the product TPP to the pre-mRNA of a biosynthetic gene modulates expression. Here we examine and hypothesize on genetic engineering approaches attempting to increase the thiamin content employing knowledge gained with the model plant Arabidopsis thaliana. We will discuss the regulatory steps that need to be taken into consideration and can be used a prerequisite for devising such strategies in crop plants. PMID:23755056

  16. Initial In Vitro Investigation of the Human Immune Response to Corneal Cells from Genetically Engineered Pigs

    PubMed Central

    Koike, Naoko; Long, Cassandra; Piluek, Jordan; Roh, Danny S.; SundarRaj, Nirmala; Funderburgh, James L.; Mizuguchi, Yoshiaki; Isse, Kumiko; Phelps, Carol J.; Ball, Suyapa F.; Ayares, David L.; Cooper, David K. C.

    2011-01-01

    Purpose. To compare the in vitro human humoral and cellular immune responses to wild-type (WT) pig corneal endothelial cells (pCECs) with those to pig aortic endothelial cells (pAECs). These responses were further compared with CECs from genetically engineered pigs (?1,3-galactosyltransferase gene-knockout [GTKO] pigs and pigs expressing a human complement-regulatory protein [CD46]) and human donors. Methods. The expression of Gal?1,3Gal (Gal), swine leukocyte antigen (SLA) class I and class II on pCECs and pAECs, with or without activation by porcine IFN-?, was tested by flow cytometry. Pooled human serum was used to measure IgM/IgG binding to and complement-dependent cytotoxicity (CDC) to cells from WT, GTKO, and GTKO/CD46 pigs. The human CD4+ T-cell response to cells from WT, GTKO, GTKO/CD46 pigs and human was tested by mixed lymphocyte reaction (MLR). Results. There was a lower level of expression of the Gal antigen and of SLA class I and II on the WT pCECs than on the WT pAECs, resulting in less antibody binding and reduced human CD4+ T-cell proliferation. However, lysis of the WT pCECs was equivalent to that of the pAECs, suggesting more susceptibility to injury. There were significantly weaker humoral and cellular responses to the pCECs from GTKO/CD46 pigs compared with the WT pCECs, although the cellular response to the GTKO/CD46 pCECs was greater than to the human CECs. Conclusions. These data provide the first report of in vitro investigations of CECs from genetically engineered pigs and suggest that pig corneas may provide an acceptable alternative to human corneas for clinical transplantation. PMID:21596821

  17. Efficacy of Sunitinib and Radiotherapy in Genetically Engineered Mouse Model of Soft-Tissue Sarcoma

    SciTech Connect

    Yoon, Sam S. Stangenberg, Lars; Lee, Yoon-Jin; Rothrock, Courtney; Dreyfuss, Jonathan M.; Baek, Kwan-Hyuck; Waterman, Peter R.; Nielsen, G. Petur; Weissleder, Ralph; Mahmood, Umar; Park, Peter J.; Jacks, Tyler

    2009-07-15

    Purpose: Sunitinib (SU) is a multitargeted receptor tyrosine kinase inhibitor of the vascular endothelial growth factor and platelet-derived growth factor receptors. The present study examined SU and radiotherapy (RT) in a genetically engineered mouse model of soft tissue sarcoma (STS). Methods and Materials: Primary extremity STSs were generated in genetically engineered mice. The mice were randomized to treatment with SU, RT (10 Gy x 2), or both (SU+RT). Changes in the tumor vasculature before and after treatment were assessed in vivo using fluorescence-mediated tomography. The control and treated tumors were harvested and extensively analyzed. Results: The mean fluorescence in the tumors was not decreased by RT but decreased 38-44% in tumors treated with SU or SU+RT. The control tumors grew to a mean of 1378 mm{sup 3} after 12 days. SU alone or RT alone delayed tumor growth by 56% and 41%, respectively, but maximal growth inhibition (71%) was observed with the combination therapy. SU target effects were confirmed by loss of target receptor phosphorylation and alterations in SU-related gene expression. Cancer cell proliferation was decreased and apoptosis increased in the SU and RT groups, with a synergistic effect on apoptosis observed in the SU+RT group. RT had a minimal effect on the tumor microvessel density and endothelial cell-specific apoptosis, but SU alone or SU+RT decreased the microvessel density by >66% and induced significant endothelial cell apoptosis. Conclusion: SU inhibited STS growth by effects on both cancer cells and tumor vasculature. SU also augmented the efficacy of RT, suggesting that this combination strategy could improve local control of STS.

  18. Lentivectors encoding immunosuppressive proteins genetically engineer pancreatic beta-cells to correct diabetes in allogeneic mice.

    PubMed

    Kojaoghlanian, T; Joseph, A; Follenzi, A; Zheng, J H; Leiser, M; Fleischer, N; Horwitz, M S; DiLorenzo, T P; Goldstein, H

    2009-03-01

    The effectiveness of genetic engineering with lentivectors to protect transplanted cells from allogeneic rejection was examined using, as a model, type 1 diabetes treatment with beta-cell transplantation, whose widespread use has been limited by the requirement for sustained immunosuppressive treatment to prevent graft rejection. We examined whether lentivectors expressing select immunosuppressive proteins encoded by the adenoviral genome early region 3 (AdE3) would protect transplanted beta-cells from an alloimmune attack. The insulin-producing beta-cell line beta TC-tet (C3HeB/FeJ-derived) was transduced with lentiviruses encoding the AdE3 proteins gp19K and RID alpha/beta. The efficiency of lentiviral transduction of beta TC-tet cells exceeded 85%. Lentivector expression of gp19K decreased surface class I major histocompatibility complex expression by over 90%, whereas RID alpha/beta expression inhibited cytokine-induced Fas upregulation by over 75%. beta TC-tet cells transduced with gp19K and RID alpha/beta lentivectors, but not with a control lentivector, provided prolonged correction of hyperglycemia after transplantation into diabetic BALB/c severe combined immunodeficient mice reconstituted with allogeneic immune effector cells or into diabetic allogeneic BALB/c mice. Thus, genetic engineering of beta-cells using gp19K- and RID alpha/beta-expressing lentiviral vectors may provide an alternative that has the potential to eliminate or reduce treatment with the potent immunosuppressive agents necessary at present for prolonged engraftment with transplanted islets. PMID:19112449

  19. Blue Tigers, Black Tapirs, & the Pied Raven of the Faroe Islands: Teaching Genetic Drift Using Real-Life Animal Examples

    ERIC Educational Resources Information Center

    Robischon, Marcel

    2015-01-01

    Genetic drift is a concept of population genetics that is central to understanding evolutionary processes and aspects of conservation biology. It is frequently taught using rather abstract representations. I introduce three real-life zoological examples, based on historical and recent color morphs of tigers, tapirs, and ravens, that can complement…

  20. Synthesis of magnetite nanoparticles for bio- and nanotechnology: genetic engineering and biomimetics of bacterial magnetosomes.

    PubMed

    Lang, Claus; Schüler, Dirk; Faivre, Damien

    2007-02-12

    Magnetotactic bacteria (MTB) have the ability to navigate along the Earth's magnetic field. This so-called magnetotaxis is a result of the presence of magnetosomes, organelles which comprise nanometer-sized intracellular crystals of magnetite (Fe(3)O(4)) enveloped by a membrane. Because of their unique characteristics, magnetosomes have a high potential for nano- and biotechnological applications, which require a specifically designed particle surface. The functionalization of magnetosomes is possible either by chemical modification of purified particles or by genetic engineering of magnetosome membrane proteins. The second approach is potentially superior to chemical approaches as a large variety of biological functions such as protein tags, fluorophores, and enzymes may be directly incorporated in a site-specific manner during magnetosome biomineralization. An alternative to the bacterial production of magnetosomes are biomimetic approaches, which aim to mimic the bacterial biomineralization pathway in vitro. In MTB a number of magnetosome proteins with putative functions in the biomineralization of the nanoparticles have been identified by genetic and biochemical approaches. The initial results obtained by several groups indicate that some of these proteins have an impact on nanomagnetite properties in vitro. In this article the key features of magnetosomes are discussed, an overview of their potential applications are given, and different strategies are proposed for the functionalization of magnetosome particles and for the biomimetism of their biomineralization pathway. PMID:17295401

  1. Criteria for Identifying and Evaluating Candidate Sites for Open-Field Trials of Genetically Engineered Mosquitoes

    PubMed Central

    Brown, David M.; Alphey, Luke S.; McKemey, Andrew; Beech, Camilla

    2014-01-01

    Abstract Recent laboratory successes in the development of genetically engineered mosquitoes for controlling pathogen transmission have fostered the need for standardized procedures for advancing the technical achievements to practical tools. It is incumbent in many cases for the same scientists doing the in-laboratory discovery research to also take on the initial challenges of developing the pathway that will move the technologies to the field. One of these challenges is having a set of criteria for selecting collaborators and sites for efficacy and safety field trials that combine rigorous science with good ethical and legal practices. Specific site-selection criteria were developed in four categories—Scientific, Regulatory, Community Engagement, and Resources—in anticipation of open-field releases of a transgenic mosquito strain designed to suppress populations of the dengue vector mosquito, Aedes aegypti. The criteria are derived from previous published material, discussions, and personal experiences with the expectation of providing guidance to laboratory scientists for addressing the conceptual and operational considerations for identifying partner researchers and countries with whom to collaborate. These criteria are not intended to be prescriptive nor can they be applied to every circumstance where genetic approaches are proposed for deployment. However, we encourage those involved in the discovery phase of research to consider each criterion during project planning activities, and where appropriate, incorporate them into a “go/no-go” decision-making process for further development and testing of the technologies. PMID:24689963

  2. Rifampicin-resistance, rpoB polymorphism and RNA polymerase genetic engineering.

    PubMed

    Alifano, Pietro; Palumbo, Carla; Pasanisi, Daniela; Talà, Adelfia

    2015-05-20

    Following its introduction in 1967, rifampicin has become a mainstay of therapy in the treatment of tuberculosis, leprosy and many other widespread diseases. Its potent antibacterial activity is due to specific inhibition of bacterial RNA polymerase. However, resistance to rifampicin was reported shortly after its introduction in the medical practice. Studies in the model organism Escherichia coli helped to define the molecular mechanism of rifampicin-resistance demonstrating that resistance is mostly due to chromosomal mutations in rpoB gene encoding the RNA polymerase ? chain. These studies also revealed the amazing potential of the molecular genetics to elucidate the structure-function relationships in bacterial RNA polymerase. The scope of this paper is to illustrate how rifampicin-resistance has been recently exploited to better understand the regulatory mechanisms that control bacterial cell physiology and virulence, and how this information has been used to maneuver, on a global scale, gene expression in bacteria of industrial interest. In particular, we reviewed recent literature regarding: (i) the effects of rpoB mutations conferring rifampicin-resistance on transcription dynamics, bacterial fitness, physiology, metabolism and virulence; (ii) the occurrence in nature of "mutant-type" or duplicated rifampicin-resistant RNA polymerases; and (iii) the RNA polymerase genetic engineering method for strain improvement and drug discovery. PMID:25481100

  3. Camelina as a sustainable oilseed crop: contributions of plant breeding and genetic engineering.

    PubMed

    Vollmann, Johann; Eynck, Christina

    2015-04-01

    Camelina is an underutilized Brassicaceae oilseed plant with a considerable agronomic potential for biofuel and vegetable oil production in temperate regions. In contrast to most Brassicaceae, camelina is resistant to alternaria black spot and other diseases and pests. Sequencing of the camelina genome revealed an undifferentiated allohexaploid genome with a comparatively large number of genes and low percentage of repetitive DNA. As there is a close relationship between camelina and the genetic model plant Arabidopsis, this review aims at exploring the potential of translating basic Arabidopsis results into a camelina oilseed crop for food and non-food applications. Recently, Arabidopsis genes for drought resistance or increased photosynthesis and overall productivity have successfully been expressed in camelina. In addition, gene constructs affecting lipid metabolism pathways have been engineered into camelina for synthesizing either long-chain polyunsaturated fatty acids, hydroxy fatty acids or high-oleic oils in particular camelina strains, which is of great interest in human food, industrial or biofuel applications, respectively. These results confirm the potential of camelina to serve as a biotechnology platform in biorefinery applications thus justifying further investment in breeding and genetic research for combining agronomic potential, unique oil quality features and biosafety into an agricultural production system. PMID:25706640

  4. Frontiers of torenia research: innovative ornamental traits and study of ecological interaction networks through genetic engineering

    PubMed Central

    2013-01-01

    Advances in research in the past few years on the ornamental plant torenia (Torenia spps.) have made it notable as a model plant on the frontier of genetic engineering aimed at studying ornamental characteristics and pest control in horticultural ecosystems. The remarkable advantage of torenia over other ornamental plant species is the availability of an easy and high-efficiency transformation system for it. Unfortunately, most of the current torenia research is still not very widespread, because this species has not become prominent as an alternative to other successful model plants such as Arabidopsis, snapdragon and petunia. However, nowadays, a more global view using not only a few selected models but also several additional species are required for creating innovative ornamental traits and studying horticultural ecosystems. We therefore introduce and discuss recent research on torenia, the family Scrophulariaceae, for secondary metabolite bioengineering, in which global insights into horticulture, agriculture and ecology have been advanced. Floral traits, in torenia particularly floral color, have been extensively studied by manipulating the flavonoid biosynthetic pathways in flower organs. Plant aroma, including volatile terpenoids, has also been genetically modulated in order to understand the complicated nature of multi-trophic interactions that affect the behavior of predators and pollinators in the ecosystem. Torenia would accordingly be of great use for investigating both the variation in ornamental plants and the infochemical-mediated interactions with arthropods. PMID:23803155

  5. Site-specific genetic engineering of the Anopheles gambiae Y chromosome.

    PubMed

    Bernardini, Federica; Galizi, Roberto; Menichelli, Miriam; Papathanos, Philippos-Aris; Dritsou, Vicky; Marois, Eric; Crisanti, Andrea; Windbichler, Nikolai

    2014-05-27

    Despite its function in sex determination and its role in driving genome evolution, the Y chromosome remains poorly understood in most species. Y chromosomes are gene-poor, repeat-rich and largely heterochromatic and therefore represent a difficult target for genetic engineering. The Y chromosome of the human malaria vector Anopheles gambiae appears to be involved in sex determination although very little is known about both its structure and function. Here, we characterize a transgenic strain of this mosquito species, obtained by transposon-mediated integration of a transgene construct onto the Y chromosome. Using meganuclease-induced homologous repair we introduce a site-specific recombination signal onto the Y chromosome and show that the resulting docking line can be used for secondary integration. To demonstrate its utility, we study the activity of a germ-line-specific promoter when located on the Y chromosome. We also show that Y-linked fluorescent transgenes allow automated sex separation of this important vector species, providing the means to generate large single-sex populations. Our findings will aid studies of sex chromosome function and enable the development of male-exclusive genetic traits for vector control. PMID:24821795

  6. Site-specific genetic engineering of the Anopheles gambiae Y chromosome

    PubMed Central

    Bernardini, Federica; Galizi, Roberto; Menichelli, Miriam; Papathanos, Philippos-Aris; Dritsou, Vicky; Marois, Eric; Crisanti, Andrea; Windbichler, Nikolai

    2014-01-01

    Despite its function in sex determination and its role in driving genome evolution, the Y chromosome remains poorly understood in most species. Y chromosomes are gene-poor, repeat-rich and largely heterochromatic and therefore represent a difficult target for genetic engineering. The Y chromosome of the human malaria vector Anopheles gambiae appears to be involved in sex determination although very little is known about both its structure and function. Here, we characterize a transgenic strain of this mosquito species, obtained by transposon-mediated integration of a transgene construct onto the Y chromosome. Using meganuclease-induced homologous repair we introduce a site-specific recombination signal onto the Y chromosome and show that the resulting docking line can be used for secondary integration. To demonstrate its utility, we study the activity of a germ-line–specific promoter when located on the Y chromosome. We also show that Y-linked fluorescent transgenes allow automated sex separation of this important vector species, providing the means to generate large single-sex populations. Our findings will aid studies of sex chromosome function and enable the development of male-exclusive genetic traits for vector control. PMID:24821795

  7. Criteria for identifying and evaluating candidate sites for open-field trials of genetically engineered mosquitoes.

    PubMed

    Brown, David M; Alphey, Luke S; McKemey, Andrew; Beech, Camilla; James, Anthony A

    2014-04-01

    Recent laboratory successes in the development of genetically engineered mosquitoes for controlling pathogen transmission have fostered the need for standardized procedures for advancing the technical achievements to practical tools. It is incumbent in many cases for the same scientists doing the in-laboratory discovery research to also take on the initial challenges of developing the pathway that will move the technologies to the field. One of these challenges is having a set of criteria for selecting collaborators and sites for efficacy and safety field trials that combine rigorous science with good ethical and legal practices. Specific site-selection criteria were developed in four categories-Scientific, Regulatory, Community Engagement, and Resources-in anticipation of open-field releases of a transgenic mosquito strain designed to suppress populations of the dengue vector mosquito, Aedes aegypti. The criteria are derived from previous published material, discussions, and personal experiences with the expectation of providing guidance to laboratory scientists for addressing the conceptual and operational considerations for identifying partner researchers and countries with whom to collaborate. These criteria are not intended to be prescriptive nor can they be applied to every circumstance where genetic approaches are proposed for deployment. However, we encourage those involved in the discovery phase of research to consider each criterion during project planning activities, and where appropriate, incorporate them into a "go/no-go" decision-making process for further development and testing of the technologies. PMID:24689963

  8. Surrogate species selection for assessing potential adverse environmental impacts of genetically engineered plants on non-target organisms

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Most regulatory authorities require that developers of genetically engineered insect-resistant (GEIR) crops evaluate the potential for these crops to have adverse impacts on valued non-target organisms (NTOs), i.e., organisms not intended to be controlled by the trait. In many cases, impacts to NTOs...

  9. Recommendations for the design of laboratory studies on non-target arthropods for risk assessment of genetically engineered plants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This paper provides recommendations on experimental design for early-tier laboratory studies used in the risk assessment process to evaluate potential adverse impacts of arthropod-resistant genetically-engineered plants on non-target arthropods. While we rely heavily on the currently used proteins f...

  10. Use of a risk communication model to evaluate dietetics professionals' viewpoints on genetically engineered foods and crops.

    PubMed

    Roberts, Kathy S; Struble, Marie Boyle; McCullum-Gomez, Christine; Wilkins, Jennifer L

    2006-05-01

    The complex issues surrounding the application of genetic engineering to food and agriculture have generated a contentious debate among diverse interest groups. One pervasive dimension in the resultant discourse is the varying perceptions of the risks and benefits of genetically engineered foods and crops. In the risk communication model, technical information is evaluated within the context of an individual's values and perceptions. The purpose of this study was to explore how dietetics professionals respond to a complex set of interrelated issues associated with genetically engineered foods and crops and to identify what varying viewpoints may exist. Participants were asked to sort a total of 48 statements distributed across eight issue areas according to level of agreement and disagreement. Using Q methodology, a total of 256 sortings were analyzed using the centroid method and varimax rotation in factor analysis. Three distinct viewpoints emerged: Precautionary (R(2)=43%), Discerning Supporter (R(2)=11%), and Promoting (R(2)=5%). Across all viewpoints, respondents agreed that dietetics professionals should employ critical thinking skills to communicate the social, economic, environmental, ethical, and technical aspects of genetically engineered foods and crops. The findings have implications for how dietetics professionals can foster an open interchange of information among diverse groups. PMID:16647331

  11. Draft Genome Sequence of the Polycyclic Aromatic Hydrocarbon-Degrading, Genetically Engineered Bioluminescent Bioreporter Pseudomonas fluorescens HK44

    SciTech Connect

    Chauhan, Archana; Layton, Alice; Williams, Daniel W; Smart, Abby E.; Ripp, Steven Anthony; Karpinets, Tatiana V; Brown, Steven D; Sayler, Gary Steven

    2011-01-01

    Pseudomonas fluorescens strain HK44 (DSM 6700) is a genetically engineered lux-based bioluminescent bioreporter. Here we report the draft genome sequence of strain HK44. Annotation of {approx}6.1 Mb sequence indicates that 30% of the traits are unique and distributed over 5 genomic islands, a prophage and two plasmids.

  12. Meeting of Bioenergy and Industrial Biotechnology research theme Public perception and regulation of biotechnology and genetic engineering

    E-print Network

    Spoel, Steven

    4th Meeting of Bioenergy and Industrial Biotechnology research theme Public perception and regulation of biotechnology and genetic engineering Morning ­ student presentations Like the previous of biotechnology considered controversial. Each topic is centred on paper(s) provided. Pairs: Amy and Ben Pierra

  13. Genetic mechanisms of antimicrobial resistance identified in Salmonella enterica, Escherichia coli, and Enteroccocus spp. isolated from U.S. food animals

    PubMed Central

    Frye, Jonathan G.; Jackson, Charlene R.

    2013-01-01

    The prevalence of antimicrobial resistance (AR) in bacteria isolated from U.S. food animals has increased over the last several decades as have concerns of AR foodborne zoonotic human infections. Resistance mechanisms identified in U.S. animal isolates of Salmonella enterica included resistance to aminoglycosides (e.g., alleles of aacC, aadA, aadB, ant, aphA, and StrAB), ?-lactams (e.g., blaCMY?2, TEM?1, PSE?1), chloramphenicol (e.g., floR, cmlA, cat1, cat2), folate pathway inhibitors (e.g., alleles of sul and dfr), and tetracycline [e.g., alleles of tet(A), (B), (C), (D), (G), and tetR]. In the U.S., multi-drug resistance (MDR) mechanisms in Salmonella animal isolates were associated with integrons, or mobile genetic elements (MGEs) such as IncA/C plasmids which can be transferred among bacteria. It is thought that AR Salmonella originates in food animals and is transmitted through food to humans. However, some AR Salmonella isolated from humans in the U.S. have different AR elements than those isolated from food animals, suggesting a different etiology for some AR human infections. The AR mechanisms identified in isolates from outside the U.S. are also predominantly different. For example the extended spectrum ?-lactamases (ESBLs) are found in human and animal isolates globally; however, in the U.S., ESBLs thus far have only been found in human and not food animal isolates. Commensal bacteria in animals including Escherichia coli and Enterococcus spp. may be reservoirs for AR mechanisms. Many of the AR genes and MGEs found in E. coli isolated from U.S. animals are similar to those found in Salmonella. Enterococcus spp. isolated from animals frequently carry MGEs with AR genes, including resistances to aminoglycosides (e.g., alleles of aac, ant, and aph), macrolides [e.g., erm(A), erm(B), and msrC], and tetracyclines [e.g., tet(K), (L), (M), (O), (S)]. Continuing investigations are required to help understand and mitigate the impact of AR bacteria on human and animal health. PMID:23734150

  14. Cell sheet-engineered bones used for the reconstruction of mandibular defects in an animal model

    PubMed Central

    DU, CHUNHUA; YAO, CHAO; LI, NINGYI; WANG, SHUANGYI; FENG, YUANYONG; YANG, XUECAI

    2015-01-01

    The aim of the present study was to investigate the generation of cell sheet-engineered bones used for the reconstruction of mandibular defects. Bone marrow stem cells (BMSCs) were cultured and induced to generate osteoblasts. Poly(lactic-co-glycolic acid) (PLGA) scaffolds were wrapped with or without cell sheets and then implanted into dogs with mandibular defects in the right side (experimental group) or the left side (control group), respectively. Subsequently, X-ray analyses, and hematoxylin and eosin staining were performed at various time points (at 4, 8, 12 or 16 weeks post-implantation; n=4 at each time point). The osteogenesis in the experimental group was significantly improved compared with that in the control group. At 16 weeks after implantation, numerous Haversian systems and a few lamellar bones were observed at the periphery. In the control group, the engineered bone (without BMSC sheets) presented fewer Haversian systems and no lamellar bones. The optical density of the fresh bone in the experimental group was significantly higher compared with that in the control group (P<0.05). In conclusion, tissue-engineered bone with the structure of lamellar bones can be generated using BMSC sheets and implantation of these bones had an improved effects compared with the control group. Cell sheet transplantation was found to enhance bone formation at the reconstruction site of the mandibular defects. PMID:26668619

  15. Release of genetically engineered insects: a framework to identify potential ecological effects

    PubMed Central

    David, Aaron S; Kaser, Joe M; Morey, Amy C; Roth, Alexander M; Andow, David A

    2013-01-01

    Genetically engineered (GE) insects have the potential to radically change pest management worldwide. With recent approvals of GE insect releases, there is a need for a synthesized framework to evaluate their potential ecological and evolutionary effects. The effects may occur in two phases: a transitory phase when the focal population changes in density, and a steady state phase when it reaches a new, constant density. We review potential effects of a rapid change in insect density related to population outbreaks, biological control, invasive species, and other GE organisms to identify a comprehensive list of potential ecological and evolutionary effects of GE insect releases. We apply this framework to the Anopheles gambiae mosquito – a malaria vector being engineered to suppress the wild mosquito population – to identify effects that may occur during the transitory and steady state phases after release. Our methodology reveals many potential effects in each phase, perhaps most notably those dealing with immunity in the transitory phase, and with pathogen and vector evolution in the steady state phase. Importantly, this framework identifies knowledge gaps in mosquito ecology. Identifying effects in the transitory and steady state phases allows more rigorous identification of the potential ecological effects of GE insect release. PMID:24198955

  16. Release of genetically engineered insects: a framework to identify potential ecological effects.

    PubMed

    David, Aaron S; Kaser, Joe M; Morey, Amy C; Roth, Alexander M; Andow, David A

    2013-10-01

    Genetically engineered (GE) insects have the potential to radically change pest management worldwide. With recent approvals of GE insect releases, there is a need for a synthesized framework to evaluate their potential ecological and evolutionary effects. The effects may occur in two phases: a transitory phase when the focal population changes in density, and a steady state phase when it reaches a new, constant density. We review potential effects of a rapid change in insect density related to population outbreaks, biological control, invasive species, and other GE organisms to identify a comprehensive list of potential ecological and evolutionary effects of GE insect releases. We apply this framework to the Anopheles gambiae mosquito - a malaria vector being engineered to suppress the wild mosquito population - to identify effects that may occur during the transitory and steady state phases after release. Our methodology reveals many potential effects in each phase, perhaps most notably those dealing with immunity in the transitory phase, and with pathogen and vector evolution in the steady state phase. Importantly, this framework identifies knowledge gaps in mosquito ecology. Identifying effects in the transitory and steady state phases allows more rigorous identification of the potential ecological effects of GE insect release. PMID:24198955

  17. Kinetics of the persistence of chromosomal DNA from genetically engineered Escherichia coli introduced into soil.

    PubMed Central

    Recorbet, G; Picard, C; Normand, P; Simonet, P

    1993-01-01

    Investigations to quantify bacterial survival and DNA persistence of a genetically engineered population of Escherichia coli introduced into soil microcosms were carried out. The survival of E. coli was monitored by plate counting and immunofluorescence methods, whereas the persistence of the DNA was evaluated by using a most-probable-number-polymerase chain reaction method. Whereas the E. coli population density declined below the plate-counting-technique detection threshold (10(2) CFU.g-1) after 15 days, 10(3) extracellular and 5 x 10(5) total DNA target sequences were still detected after 40 days. Additionally, the E. coli cell counts fell below the detection limit of the immunofluorescence method (10(5) cells.g-1) before the end of the experiment. Colony hybridizations did not reveal gene transfer to the indigenous microflora. These results confirm the persistence of residual E. coli target sequences that could not be detected by the classical cell counting method and offer promising applications for the environmental detection of microorganisms, either engineered, pathogenic, or released for beneficial effects. Images PMID:8285718

  18. A genetic replacement system for selection-based engineering of essential proteins

    PubMed Central

    2012-01-01

    Background Essential genes represent the core of biological functions required for viability. Molecular understanding of essentiality as well as design of synthetic cellular systems includes the engineering of essential proteins. An impediment to this effort is the lack of growth-based selection systems suitable for directed evolution approaches. Results We established a simple strategy for genetic replacement of an essential gene by a (library of) variant(s) during a transformation. The system was validated using three different essential genes and plasmid combinations and it reproducibly shows transformation efficiencies on the order of 107 transformants per microgram of DNA without any identifiable false positives. This allowed for reliable recovery of functional variants out of at least a 105-fold excess of non-functional variants. This outperformed selection in conventional bleach-out strains by at least two orders of magnitude, where recombination between functional and non-functional variants interfered with reliable recovery even in recA negative strains. Conclusions We propose that this selection system is extremely suitable for evaluating large libraries of engineered essential proteins resulting in the reliable isolation of functional variants in a clean strain background which can readily be used for in vivo applications as well as expression and purification for use in in vitro studies. PMID:22898007

  19. Genetic engineering and metabolite profiling for overproduction of polyhydroxybutyrate in cyanobacteria.

    PubMed

    Hondo, Sayaka; Takahashi, Masatoshi; Osanai, Takashi; Matsuda, Mami; Hasunuma, Tomohisa; Tazuke, Akio; Nakahira, Yoichi; Chohnan, Shigeru; Hasegawa, Morifumi; Asayama, Munehiko

    2015-11-01

    Genetic engineering and metabolite profiling for the overproduction of polyhydroxybutyrate (PHB), which is a carbon material in biodegradable plastics, were examined in the unicellular cyanobacterium Synechocystis sp. PCC 6803. Transconjugants harboring cyanobacterial expression vectors that carried the pha genes for PHB biosynthesis were constructed. The overproduction of PHB by the engineering cells was confirmed through microscopic observations using Nile red, transmission electron microscopy (TEM), or nuclear magnetic resonance (NMR). We successfully recovered PHB from transconjugants prepared from nitrogen-depleted medium without sugar supplementation in which PHB reached approximately 7% (w/w) of the dry cell weight, showing a value of 12-fold higher productivity in the transconjugant than that in the control strain. We also measured the intracellular levels of acetyl-CoA, acetoacetyl-CoA, and 3-hydroxybutyryl-CoA (3HB-CoA), which are intermediate products for PHB. The results obtained indicated that these products were absent or at markedly low levels when cells were subjected to the steady-state growth phase of cultivation under nitrogen depletion for the overproduction of bioplastics. Based on these results, efficient factors were discussed for the overproduction of PHB in recombinant cyanobacteria. PMID:26055446

  20. A prototype stable RNA identification cassette for monitoring plasmids of genetically engineered microorganisms

    NASA Technical Reports Server (NTRS)

    Hedenstierna, K. O.; Lee, Y. H.; Yang, Y.; Fox, G. E.

    1993-01-01

    A prototype stable RNA identification cassette for monitoring genetically engineered plasmids carried by strains of Escherichia coli has been developed. The cassette consists of a Vibrio proteolyticus 5S ribosomal RNA (rRNA) gene surrounded by promoters and terminators from the rrnB operon of Escherischia coli. The identifier RNA is expressed and successfully processed so that approximately 30% of the 5S rRNA isolated from either whole cells or 70S ribosomes is of the V. proteolyticus type. Cells carrying the identifier are readily detectable by hybridization. Accurate measurements show that the identification cassette has little effect on fitness compared to a strain containing an analogous plasmid carrying wild type E. coli 5S rRNA, and the V. proteolyticus 5S rRNA gene is not inactivated after prolonged growth. These results demonstrate the feasibility of developing small standardized identification cassettes that can utilize already existing highly sensitive rRNA detection methods. Cassettes of this type could in principle be incorporated into either the engineered regions of recombinant plasmids or their hosts.

  1. Different methods of selecting animals for genotyping to maximize the amount of genetic information known in the population

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A simulation study was carried out to develop and compare different methods of sampling animals to be genotyped. The simulated pedigrees included 5,000 animals and were assigned genotypes based on assumed allelic frequencies (favorable/unfavorable) of 0.3/0.7, 0.5/0.5, and 0.8/0.2. A real beef cat...

  2. Investigation of genetically-engineered beta-sheet polypeptides for nanoelectronics

    NASA Astrophysics Data System (ADS)

    Rana, Narender

    2007-12-01

    Ongoing miniaturization in integrated circuit (IC) device fabrication via conventional lithography faces increasing technical challenges and imposes significant performance limitations on devices and interconnects stemming from the fundamental physics of electron transport. This drives the need to explore other nanofabrication approaches, such as self-assembly, and alternate device or interconnect structures with novel electron transport mechanisms, such as ballistic electron transport. Molecular self-assembly, ubiquitous in biology and bio-inspired materials, might have tremendous potential for nanoelectronic applications. Specifically, genetically-engineered beta-sheet polypeptides offer certain key attributes for nanoelectronic applications. These attributes include: controllable self-assembly, potential to form one dimensional quantum channels for ballistic electron transport, and substrate-specific interactions for interfacial engineering. This dissertation explores and evaluates the nanowire self-assembly characteristics of several de novo genetically-engineered beta-sheet polypeptides (synthesized by our group) on various substrates for applications in nanoelectronic interconnect schemes. In addition, substrate-attachment of the beta-sheet polypeptide nanowire structures is investigated and preliminary electrical testing of a polypeptide nanowire fibril is presented. Chapters 1 and 2 provide an overall introduction and discuss the characterization techniques utilized in the experimental work. Chapter 3 describes a detailed self-assembly study of various polypeptides and documents the formulation and deposition of controlled, linear self-assemblies of polypeptides. It was determined that control of the concentration and deposition-time enables the deposition of linear ordered polypeptide assemblies on substrates. A predominance of bilayer stacking of polypeptide sheets in the solution-formed linear assemblies has been observed. Template-directed self-assembly of linear polypeptide assemblies has also been documented on graphite surfaces. This has demonstrated the potential for epitaxial or template-directed ordering of polypeptides on substrates for potential nanoelectronic applications. Chapter 4 describes an adhesion study of polypeptide nanostructures on various substrates. A forced-scanning methodology based on atomic force microscopy was employed and used to identify specific (covalent) and non-specific (physisorbed) interactions of the polypeptide to a variety of substrates. This information is important for substrate and electrode attachment of polypeptides for nanoelectronic applications. Chapter 5 presents the results of scanning tunneling microscopy of polypeptide monolayers on graphite and theoretical charge density calculations. These results confirm that this polypeptide exhibits a beta-sheet conformation on the graphite substrate.

  3. Demographic and genetic status of an isolated population of bog turtles (Glyptemys muhlenbergii): Implications for managing small populations of long-lived animals

    USGS Publications Warehouse

    Pittman, Shannon E.; King, T.L.; Faurby, S.; Dorcas, M.E.

    2011-01-01

    In this study, we sought to determine the population stability and genetic diversity of one isolated population of the federally-threatened bog turtle (Glyptemys muhlenbergii) in North Carolina. Using capture-recapture data, we estimated adult survival and population growth rate from 1992 to 2007. We found that the population decreased from an estimated 36 adult turtles in 1994 to approximately 11 adult turtles in 2007. We found a constant adult survival of 0. 893 (SE = 0. 018, 95% confidence interval, 0. 853-0. 924) between 1992 and 2007. Using 18 microsatellite markers, we compared the genetic status of this population with five other bog turtle populations. The target population displayed allelic richness (4. 8 ?? 0. 5) and observed heterozygosity (0. 619 ?? 0. 064) within the range of the other bog turtle populations. Coalescent analysis of population growth rate, effective population size, and timing of population structuring event also indicated the genetics of the target population were comparable to the other populations studied. Estimates of effective population size were a proportion of the census size in all populations except the target population, in which the effective population size was larger than the census size (30 turtles vs. 11 turtles). We attribute the high genetic diversity in the target population to the presence of multiple generations of old turtles. This study illustrates that the demographic status of populations of long-lived species may not be reflected genetically if a decline occurred recently. Consequently, the genetic integrity of populations of long-lived animals experiencing rapid demographic bottlenecks may be preserved through conservation efforts effective in addressing demographic problems. ?? 2011 Springer Science+Business Media B.V.

  4. Animal Watching: Outdoors and In.

    ERIC Educational Resources Information Center

    McLure, John W.

    2001-01-01

    Describes using domesticated, wild, or feral animals to teach students about nature and animal behavior. Connections can be made with psychology, economics, genetics, history, art, and other disciplines. The study of animal behavior provides opportunities for harmless student experimentation. (SAH)

  5. Genetics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The genus Capsicum represents one of several well characterized Solanaceous genera. A wealth of classical and molecular genetics research is available for the genus. Information gleaned from its cultivated relatives, tomato and potato, provide further insight for basic and applied studies. Early ...

  6. Genetics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Maintaining genetic variation in wild populations of Arctic organisms is fundamental to the long-term persistence of high latitude biodiversity. Variability is important because it provides options for species to respond to changing environmental conditions and novel challenges such as emerging path...

  7. Animal welfare: an animal science approach.

    PubMed

    Koknaroglu, H; Akunal, T

    2013-12-01

    Increasing world population and demand for animal-derived protein puts pressure on animal production to meet this demand. For this purpose animal breeding efforts were conducted to obtain the maximum yield that the genetic makeup of the animals permits. Under the influence of economics which is the driving force behind animal production, animal farming became more concentrated and controlled which resulted in rearing animals under confinement. Since more attention was given on economics and yield per animal, animal welfare and behavior were neglected. Animal welfare which can be defined as providing environmental conditions in which animals can display all their natural behaviors in nature started gaining importance in recent years. This does not necessarily mean that animals provided with good management practices would have better welfare conditions as some animals may be distressed even though they are in good environmental conditions. Consumers are willing to pay more for welfare-friendly products (e.g.: free range vs caged egg) and this will change the animal production practices in the future. Thus animal scientists will have to adapt themselves for the changing animal welfare rules and regulations that differ for farm animal species and countries. In this review paper, animal welfare is discussed from an animal science standpoint. PMID:23664009

  8. A Compendium of the Mouse Mammary Tumor Biologist: From the Initial Observations in the House Mouse to the Development of Genetically Engineered Mice

    PubMed Central

    Cardiff, Robert D.; Kenney, Nicholas

    2011-01-01

    For over a century, mouse mammary tumor biology and the associated mouse mammary tumor virus (MMTV) have served as the foundation for experimental cancer research, in general, and, in particular, experimental breast cancer research. Spontaneous mouse mammary tumors were the basis for studies of the natural history of neoplasia, oncogenic viruses, host responses, endocrinology and neoplastic progression. However, lacking formal proof of a human mammary tumor virus, the preeminence of the mouse model faded in the 1980s. Since the late 1980s, genetically engineered mice (GEM) have proven extremely useful for studying breast cancer and have become the animal model for human breast cancer. Hundreds of mouse models of human breast cancer have been developed since the first demonstration in 1984. The GEM have attracted a new generation of molecular and cellular biologists eager to apply their skill sets to these surrogates of the human disease. Newcomers often enter the field without an appreciation of the origins of mouse mammary tumor biology and the basis for many of the prevailing concepts. Our purpose in writing this compendium is to extend an “olive branch” while simultaneously deepen the knowledge of the novice mouse mammary tumor biologist as they journey into a field rich in pathology and genetics spanning several centuries. PMID:20961975

  9. Monitoring and identifying genetically-engineered microorganisms in the environment by time-resolved laser fluorometry

    SciTech Connect

    Basile, F.

    1992-01-01

    A large percentage of the applications of Genetically Engineered Microorganisms (GEMs) involve their release into the environment. At the present time there is no rapid analytical method that can accurately identify and quantify the number of microorganisms and their foreign genes. In the past several years the author's laboratory has used successfully laser-based enzymatic assays to identify and differentiate pathogens, microorganisms, and genetically modified microorganisms. This work focused on the use of the above technology to track and identify agricultural beneficially GEMs that have been released into the environment. The first stage of this work dealt with the detection of the marker gene, the lactose operon. It was successfully demonstrated that the laser-based enzymatic assay can detect enzymatic activity in E. coli after 5 minutes of induction. Moreover, the author has achieved quantitation of GEMs in the laboratory down to 10[sup 4] cells with only a 30 minute incubation time. The second stage of this work dealt with the characterization of the analytical blank present in environmental samples. Strategies were devised to circumvent this interference and new substrates were synthesized that improved the S/B of the analysis. The last stage of this research dealt with devising new instrumental methods to detect small number (single cell) of microorganisms. These included incorporation of time-resolved detection in flow cytometry, Capillary Electrophoresis of microorganisms, and two-photon spectroscopy of centrosymmetric probes. The results found here will complement the large array of techniques available for monitoring and identifying GEMs in the environment. Ultimately, the technique chosen will depend heavily on the type of gene being monitored, the sensitivity required, and the environmental conditions.

  10. Generation and Genetic Engineering of Human Induced Pluripotent Stem Cells Using Designed Zinc Finger Nucleases

    PubMed Central

    Ramalingam, Sivaprakash; London, Viktoriya; Kandavelou, Karthikeyan; Cebotaru, Liudmila; Guggino, William; Civin, Curt

    2013-01-01

    Zinc finger nucleases (ZFNs) have become powerful tools to deliver a targeted double-strand break at a pre-determined chromosomal locus in order to insert an exogenous transgene by homology-directed repair. ZFN-mediated gene targeting was used to generate both single-allele chemokine (C-C motif) receptor 5 (CCR5)-modified human induced pluripotent stem cells (hiPSCs) and biallele CCR5-modified hiPSCs from human lung fibroblasts (IMR90 cells) and human primary cord blood mononuclear cells (CBMNCs) by site-specific insertion of stem cell transcription factor genes flanked by LoxP sites into the endogenous CCR5 locus. The Oct4 and Sox2 reprogramming factors, in combination with valproic acid, induced reprogramming of human lung fibroblasts to form CCR5-modified hiPSCs, while 5 factors, Oct4/Sox2/Klf4/Lin28/Nanog, induced reprogramming of CBMNCs. Subsequent Cre recombinase treatment of the CCR5-modified IMR90 hiPSCs resulted in the removal of the Oct4 and Sox2 transgenes. Further genetic engineering of the single-allele CCR5-modified IMR90 hiPSCs was achieved by site-specific addition of the large CFTR transcription unit to the remaining CCR5 wild-type allele, using CCR5-specific ZFNs and a donor construct containing tdTomato and CFTR transgenes flanked by CCR5 homology arms. CFTR was expressed efficiently from the endogenous CCR5 locus of the CCR5-modified tdTomato/CFTR hiPSCs. These results suggest that it might be feasible to use ZFN-evoked strategies to (1) generate precisely targeted genetically well-defined patient-specific hiPSCs, and (2) then to reshape their function by targeted addition and expression of therapeutic genes from the CCR5 chromosomal locus for autologous cell-based transgene-correction therapy to treat various recessive monogenic human diseases in the future. PMID:22931452

  11. Nontoxic Genetic Engineering of Mesenchymal Stem Cells Using Serum-Compatible Pullulan-Spermine/DNA Anioplexes

    PubMed Central

    Thakor, Devang K.; Obata, Hideaki; Nagane, Kentaro; Saito, Shigeru

    2011-01-01

    Genetic modification of stem cells could be applied to initiate/enhance their secretion of therapeutic molecules, alter their biological properties, or label them for in vivo tracking. We recently developed a negatively charged gene carrier (“anioplex”) based on pullulan-spermine, a conjugate prepared from a natural polysaccharide and polyamine. In rat mesenchymal stem cells (MSCs), anioplex-derived reporter gene activity was comparable to or exceeded that obtained using a commercial cationic lipid reagent. Transfection in the growth medium with 15% serum and antibiotics was approximately sevenfold more effective than in serum-free conditions. Cytotoxicity was essentially indiscernible after 24?h of anioplex transfection with 20??g/mL DNA, in contrast to cationic lipid transfection that resulted in 40%–60% death of target MSCs. Anioplex-derived reporter gene activity persisted throughout the entire 3-week study, with post-transfection MSCs appearing to maintain osteogenic, adipogenic, and chondrogenic multipotency. In particular, chondrogenic pellet formation of differentiating human MSCs was significantly inhibited after lipofection but not after aniofection, which further indicates the biological inertness of pullulan-spermine/DNA anioplexes. Collectively, these data introduce a straightforward technology for genetic engineering of adult stem/progenitor cells under physiological niche-like conditions. Moreover, reporter gene activity was observed in rat spinal cords after minimally invasive intrathecal implantation, suggesting effective engraftment of donor MSCs. It is therefore plausible that anioplex-transfected MSCs or other stem/progenitor cells with autologous potential could be applied to disorders such as neurotrauma or neuropathic pain that involve the spinal cord and brain. PMID:20698746

  12. Animal Models for Neural Diseases

    PubMed Central

    Gary, W. J; Demattos, Ronald B.; Weinstein, Edward J.; Philbert, Martin A.; Pardo, Ingrid D.; Brown, Tom P.

    2015-01-01

    Animal Models of Neural Disease” was the focus of General Session 5 at a 2010 scientific symposium that was sponsored jointly by the Society of Toxicologic Pathology (STP) and the International Federation of Societies of Toxicologic Pathologists (IFSTP). The objective was to consider issues that dictate the choice of animal models for neuropathology-based studies used to investigate neurological diseases and novel therapeutic agents to treat them. In some cases, no animal model exists that recapitulates the attributes of the human disease (e.g., fibromyalgia syndrome). Alternatively, numerous animal models are available for other conditions, so an essential consideration is selecting the most appropriate experimental system (e.g., Alzheimer’s disease). New technologies (e.g., genetically engineered rodent models) promise the opportunity to generate suitable animal models for syndromes that currently lack any in vivo animal model, while in vitro models offer the opportunity to evaluate xenobiotic effects in specific neural cell populations. The complex nature of neurological disease requires regular reassessment of available and potential options to ensure that animal-derived data sets support translational medicine efforts to improve public health. PMID:21119053

  13. A genetically engineered live-attenuated simian-human immunodeficiency virus that co-expresses the RANTES gene improves the magnitude of cellular immunity in rhesus macaques

    SciTech Connect

    Shimizu, Yuya; Inaba, Katsuhisa; Kaneyasu, Kentaro; Ibuki, Kentaro; Himeno, Ai; Okoba, Masashi; Goto, Yoshitaka; Hayami, Masanori; Miura, Tomoyuki; Haga, Takeshi . E-mail: a0d518u@cc.miyazaki-u.ac.jp

    2007-04-25

    Regulated-on-activation-normal-T-cell-expressed-and-secreted (RANTES), a CC-chemokine, enhances antigen-specific T helper (Th) type-1 responses against HIV-1. To evaluate the adjuvant effects of RANTES against HIV vaccine candidate in SHIV-macaque models, we genetically engineered a live-attenuated SHIV to express the RANTES gene (SHIV-RANTES) and characterized the virus's properties in vivo. After the vaccination, the plasma viral loads were same in the SHIV-RANTES-inoculated monkeys and the parental nef-deleted SHIV (SHIV-NI)-inoculated monkeys. SHIV-RANTES provided some immunity in monkeys by remarkably increasing the antigen-specific CD4{sup +} Th cell-proliferative response and by inducing an antigen-specific IFN-{gamma} ELISpot response. The magnitude of the immunity in SHIV-RANTES-immunized animals, however, failed to afford greater protection against a heterologous pathogenic SHIV (SHIV-C2/1) challenge compared to control SHIV-NI-immunized animals. SHIV-RANTES immunized monkeys, elicited robust cellular CD4{sup +} Th responses and IFN-{gamma} ELISpot responses after SHIV-C2/1 challenge. These findings suggest that the chemokine RANTES can augment vaccine-elicited, HIV-specific CD4{sup +} T cell responses.

  14. Genetic engineering of Pyrococcus furiosus to use chitin as a carbon source

    PubMed Central

    2013-01-01

    Background Bioinformatic analysis of the genes coding for the chitinase in Pyrococcus furiosus and Thermococcus kodakarensis revealed that most likely a one nucleotide insertion in Pyrococcus caused a frame shift in the chitinase gene. This splits the enzyme into two separate genes, PF1233 and PF1234, in comparison to Thermococcus kodakarensis. Furthermore, our attempts to grow the wild type strain of Pyrococcus furiosus on chitin were negative. From these data we assume that Pyrococcus furiosus is most likely unable to use chitin as a carbon source. The aim of this study was to analyze in vivo if the one nucleotide insertion is responsible for the inability to grow on chitin, using a recently described genetic system for Pyrococcus furiosus. Results A marker-less genetic system for Pyrococcus furiosus was developed using simvastatin for positive selection and 6-methylpurine for negative selection. Resistance against simvastatin was achieved by overexpression of the hydroxymethylglutaryl coenzyme A reductase gene. For the resistance to 6-methylpurine the hypoxanthine-guanine phosphoribosyltransferase gene was deleted. This system was used to delete the additional nucleotide at position 1006 in PF1234. The resulting chitinase in the mutant strain was a single subunit enzyme and aligns perfectly to the enzyme from Thermococcus kodakarensis. A detailed analysis of the wild type and the mutant using counted cell numbers as well as ATP and acetate production as growth indicators revealed that only the mutant is able to use chitin as a carbon source. An additional mutant strain containing a reduced chitinase version containing just one catalytic and one chitin-binding domain showed diminished growth on chitin in comparison to the mutant containing the single large enzyme. Conclusions Wild type Pyrococcus furiosus is most likely unable to grow on chitin in the natural biotope due to a nucleotide insertion which separates the chitinase gene into two ORFs, whereas a genetically engineered strain with the deleted nucleotide is able to grow on chitin. The overall high sequence identity of the two chitinases between P. furiosus and T. kodakarensis indicates that this mutation occurred very recently or there is still some kind of selection pressure for a functional enzyme using programmed +/?1 frameshifting. PMID:23391022

  15. A Cell Lysis and Protein Purification - Single Molecule Assay Devices for Evaluation of Genetically Engineered Proteins

    NASA Astrophysics Data System (ADS)

    Nakyama, Tetsuya; Tabata, Kazuhito; Noji, Hiroyuki; Yokokawa, Ryuji

    We have developed two devices applicable to evaluate genetically engineered proteins in single molecule assay: on-chip cell lysis device, and protein purification - assay device. A motor protein, F1-ATPase expressed in E.coli, was focused in this report as a target protein. Cell lysis was simply performed by applying pulse voltage between Au electrodes patterned by photolithography, and its efficiency was determined by absorptiometry. The subsequent processes, purification and assay of extracted proteins, were demonstrated in order to detect F1-ATPase and to evaluate its activity. The specific bonding between his-tag in F1-ATPase and Ni-NTA coated on a glass surface was utilized for the purification process. After immobilization of F1-ATPase, avidin-coated microspheres and adenosine tri-phosphate (ATP) solution were infused sequentially to assay the protein. Microsphere rotation was realized by activity of F1-ATPase corresponding to ATP hydrolysis. Results show that the cell lysis device, at the optimum condition, extracts enough amount of protein for single molecule assay. Once cell lysate was injected to the purification - assay device, proteins were diffused in the lateral direction in a Y-shape microchannel. The gradient of protein concentratioin provides an optimal concentration for the assay i.e. the highest density of rotating beads. Density of rotating beads is also affected by the initial concentration of protein injected to the device. The optimum concentration was achieved by our cell lysis device not by the conventional method by ultrasonic wave. Rotation speed was analyzed for several microspheres assayed in the purification - assay device, and the results were compatible to that of conventional assay in which F1-ATPase was purified in bulk scale. In conclusion, we have demonstrated on-chip cell lysis and assay appropriate for the sequential analysis without any pretreatment. On-chip devices replacing conventional bioanalytical methods will be integrated a total analysis system to evaluate engineered protein and DNA.

  16. Genetic diversity and antimicrobial resistance of Escherichia coli from human and animal sources uncovers multiple resistances from human sources

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Escherichia coli are widely used as indicators of fecal contamination, and in some cases to identify host sources of fecal contamination in surface water. Prevalence, genetic diversity and antimicrobial susceptibility were determined for 600 generic E. coli isolates obtained from surface water and s...

  17. Perspectives on genetic animal models of serotonin toxicity Allan V. Kalueff *, Justin L. LaPorte, Dennis L. Murphy

    E-print Network

    Kalueff, Allan V.

    of some recreational drugs, such as 3,4-methylenedioxymethamphetamine (MDMA) (Demirkiran et al., 1996 administration of serotonergic drugs. In addition to pharmacological stimulation, some genetic and other factors psychotropic drugs, including selective serotonin reuptake inhibitors (SSRIs) (Blakely, 2001; D.L. Murphy et al

  18. Reveal, A General Reverse Engineering Algorithm for Inference of Genetic Network Architectures

    NASA Technical Reports Server (NTRS)

    Liang, Shoudan; Fuhrman, Stefanie; Somogyi, Roland

    1998-01-01

    Given the immanent gene expression mapping covering whole genomes during development, health and disease, we seek computational methods to maximize functional inference from such large data sets. Is it possible, in principle, to completely infer a complex regulatory network architecture from input/output patterns of its variables? We investigated this possibility using binary models of genetic networks. Trajectories, or state transition tables of Boolean nets, resemble time series of gene expression. By systematically analyzing the mutual information between input states and output states, one is able to infer the sets of input elements controlling each element or gene in the network. This process is unequivocal and exact for complete state transition tables. We implemented this REVerse Engineering ALgorithm (REVEAL) in a C program, and found the problem to be tractable within the conditions tested so far. For n = 50 (elements) and k = 3 (inputs per element), the analysis of incomplete state transition tables (100 state transition pairs out of a possible 10(exp 15)) reliably produced the original rule and wiring sets. While this study is limited to synchronous Boolean networks, the algorithm is generalizable to include multi-state models, essentially allowing direct application to realistic biological data sets. The ability to adequately solve the inverse problem may enable in-depth analysis of complex dynamic systems in biology and other fields.

  19. Behavior of pollutant-degrading microorganisms in aquifers: Predictions for genetically engineered organisms

    USGS Publications Warehouse

    Krumme, M.L.; Smith, R.L.; Egestorff, J.; Thiem, S.M.; Tiedje, J.M.; Timmis, K.N.; Dwyer, D.F.

    1994-01-01

    Bioremediation via environmental introductions of degradative microorganisms requires that the microbes survive in substantial numbers and effect an increase in the rate and extent of pollutant removal. Combined field and microcosm studies were used to assess these abilities for laboratory-grown bacteria. Following introduction into a contaminated aquifer, viable cells of Pseudomonas sp. B13 were present in the contaminant plume for 447 days; die-off was rapid in pristine areas. In aquifer microcosms, survival of B13 and FR120, a genetically engineered derivative of B13 having enhanced catabolic capabilities for substituted aromatics, was comparable to B13 field results; both bacteria degraded target pollutants in microcosms made with aquifer samples from the aerobic zone of the pollutant plume. Results suggest that field studies with nonrecombinant microorganisms may be coupled to laboratory studies with derivative strains to estimate their bioremediative efficacy. Furthermore, laboratory strains of bacteria can survive for extended periods of time in nature and thus may have important bioremediative applications. ?? 1994 American Chemical Society.

  20. Genetic Network Inference: From Co-Expression Clustering to Reverse Engineering

    NASA Technical Reports Server (NTRS)

    Dhaeseleer, Patrik; Liang, Shoudan; Somogyi, Roland

    2000-01-01

    Advances in molecular biological, analytical, and computational technologies are enabling us to systematically investigate the complex molecular processes underlying biological systems. In particular, using high-throughput gene expression assays, we are able to measure the output of the gene regulatory network. We aim here to review datamining and modeling approaches for conceptualizing and unraveling the functional relationships implicit in these datasets. Clustering of co-expression profiles allows us to infer shared regulatory inputs and functional pathways. We discuss various aspects of clustering, ranging from distance measures to clustering algorithms and multiple-duster memberships. More advanced analysis aims to infer causal connections between genes directly, i.e., who is regulating whom and how. We discuss several approaches to the problem of reverse engineering of genetic networks, from discrete Boolean networks, to continuous linear and non-linear models. We conclude that the combination of predictive modeling with systematic experimental verification will be required to gain a deeper insight into living organisms, therapeutic targeting, and bioengineering.

  1. The first crop plant genetically engineered to release an insect pheromone for defence.

    PubMed

    Bruce, Toby J A; Aradottir, Gudbjorg I; Smart, Lesley E; Martin, Janet L; Caulfield, John C; Doherty, Angela; Sparks, Caroline A; Woodcock, Christine M; Birkett, Michael A; Napier, Johnathan A; Jones, Huw D; Pickett, John A

    2015-01-01

    Insect pheromones offer potential for managing pests of crop plants. Volatility and instability are problems for deployment in agriculture but could be solved by expressing genes for the biosynthesis of pheromones in the crop plants. This has now been achieved by genetically engineering a hexaploid variety of wheat to release (E)-?-farnesene (E?f), the alarm pheromone for many pest aphids, using a synthetic gene based on a sequence from peppermint with a plastid targeting amino acid sequence, with or without a gene for biosynthesis of the precursor farnesyl diphosphate. Pure E?f was produced in stably transformed wheat lines with no other detectable phenotype but requiring targeting of the gene produced to the plastid. In laboratory behavioural assays, three species of cereal aphids were repelled and foraging was increased for a parasitic natural enemy. Although these studies show considerable potential for aphid control, field trials employing the single and double constructs showed no reduction in aphids or increase in parasitism. Insect numbers were low and climatic conditions erratic suggesting the need for further trials or a closer imitation, in the plant, of alarm pheromone release. PMID:26108150

  2. Establishment of the mathematical model for diagnosing the engine valve faults by genetic programming

    NASA Astrophysics Data System (ADS)

    Yang, Wen-Xian

    2006-05-01

    Available machine fault diagnostic methods show unsatisfactory performances on both on-line and intelligent analyses because their operations involve intensive calculations and are labour intensive. Aiming at improving this situation, this paper describes the development of an intelligent approach by using the Genetic Programming (abbreviated as GP) method. Attributed to the simple calculation of the mathematical model being constructed, different kinds of machine faults may be diagnosed correctly and quickly. Moreover, human input is significantly reduced in the process of fault diagnosis. The effectiveness of the proposed strategy is validated by an illustrative example, in which three kinds of valve states inherent in a six-cylinders/four-stroke cycle diesel engine, i.e. normal condition, valve-tappet clearance and gas leakage faults, are identified. In the example, 22 mathematical functions have been specially designed and 8 easily obtained signal features are used to construct the diagnostic model. Different from existing GPs, the diagnostic tree used in the algorithm is constructed in an intelligent way by applying a power-weight coefficient to each feature. The power-weight coefficients vary adaptively between 0 and 1 during the evolutionary process. Moreover, different evolutionary strategies are employed, respectively for selecting the diagnostic features and functions, so that the mathematical functions are sufficiently utilized and in the meantime, the repeated use of signal features may be fully avoided. The experimental results are illustrated diagrammatically in the following sections.

  3. The first crop plant genetically engineered to release an insect pheromone for defence

    PubMed Central

    Bruce, Toby J.A.; Aradottir, Gudbjorg I.; Smart, Lesley E.; Martin, Janet L.; Caulfield, John C.; Doherty, Angela; Sparks, Caroline A.; Woodcock, Christine M.; Birkett, Michael A.; Napier, Johnathan A.; Jones, Huw D.; Pickett, John A.

    2015-01-01

    Insect pheromones offer potential for managing pests of crop plants. Volatility and instability are problems for deployment in agriculture but could be solved by expressing genes for the biosynthesis of pheromones in the crop plants. This has now been achieved by genetically engineering a hexaploid variety of wheat to release (E)-?-farnesene (E?f), the alarm pheromone for many pest aphids, using a synthetic gene based on a sequence from peppermint with a plastid targeting amino acid sequence, with or without a gene for biosynthesis of the precursor farnesyl diphosphate. Pure E?f was produced in stably transformed wheat lines with no other detectable phenotype but requiring targeting of the gene produced to the plastid. In laboratory behavioural assays, three species of cereal aphids were repelled and foraging was increased for a parasitic natural enemy. Although these studies show considerable potential for aphid control, field trials employing the single and double constructs showed no reduction in aphids or increase in parasitism. Insect numbers were low and climatic conditions erratic suggesting the need for further trials or a closer imitation, in the plant, of alarm pheromone release. PMID:26108150

  4. [Decoloration and bioaugmentation on azo dye by immobilized genetically engineered strain].

    PubMed

    Jin, Ruo-Fei; Zhou, Ji-Ti; Wang, Jing; Cao, Tong-Chuan

    2007-11-01

    Decoloration and bioaugmentation on azo dye are investigated by using immobilized genetically engineered strain Escherichia coli JM109 (pGEX-AZR) on marcroporous foam carriers. The kinetics of the acid red GR decolorization by the immobilized E. coli JM109 (pGEX-AZR) accords with Andrews model proved by our experiments, and the kinetic parameters, mu(max,c), K(c) and K(ic), are found to be 49.2 mg x (g x h)(-1), 710.43 mg x L(-1) and 681.62 mg x L(-1) respectively. For continuous operating in the anaerobic SBRs with 10% inoculation of Escherichia coli JM109 (pGEX-AZR) on marcroporous foam carriers for 32 d, both the tolerance to red GR concentration shock and the colorific removal in the bioaugmented anaerobic SBRs are higher than the control system, and the acid red GR decoloration rate reached 90%. Changes in microbial community have been detected by the RISA, in which the introduced immobilized GEM and preponderant mixed culture were subsisted steadily in sludge systems. PMID:18290489

  5. Genetic engineering activates biosynthesis of aromatic fumaric acid amides in the human pathogen Aspergillus fumigatus.

    PubMed

    Kalb, Daniel; Heinekamp, Thorsten; Lackner, Gerald; Scharf, Daniel H; Dahse, Hans-Martin; Brakhage, Axel A; Hoffmeister, Dirk

    2015-03-01

    The Aspergillus fumigatus nonribosomal peptide synthetase FtpA is among the few of this species whose natural product has remained unknown. Both FtpA adenylation domains were characterized in vitro. Fumaric acid was identified as preferred substrate of the first and both l-tyrosine and l-phenylalanine as preferred substrates of the second adenylation domain. Genetically engineered A. fumigatus strains expressed either ftpA or the regulator gene ftpR, encoded in the same cluster of genes, under the control of the doxycycline-inducible tetracycline-induced transcriptional activation (tet-on) cassette. These strains produced fumaryl-l-tyrosine and fumaryl-l-phenylalanine which were identified by liquid chromatography and high-resolution mass spectrometry. Modeling of the first adenylation domain in silico provided insight into the structural requirements to bind fumaric acid as peptide synthetase substrate. This work adds aromatic fumaric acid amides to the secondary metabolome of the important human pathogen A. fumigatus which was previously not known as a producer of these compounds. PMID:25527545

  6. Controlled field release of a bioluminescent genetically engineered microorganism for bioremediation process monitoring and control

    SciTech Connect

    Ripp, S.; Nivens, D.E.; Ahn, Y.; Werner, C.; Jarrell, J. IV; Easter, J.P.; Cox, C.D.; Burlage, R.S.; Sayler, G.S.

    2000-03-01

    Pseudomonas fluorescens HK44 represents the first genetically engineered microorganism approved for field testing in the United States for bioremediation purposes. Strain HK44 harbors an introduced lux gene fused within a naphthalene degradative pathway, thereby allowing this recombinant microbe to bioluminescent as it degrades specific polyaromatic hydrocarbons such as naphthalene. The bioremediation process can therefore be monitored by the detection of light. P. fluorescens HK44 was inoculated into the vadose zone of intermediate-scale, semicontained soil lysimeters contaminated with naphthalene, anthracene, and phenanthrene, and the population dynamics were followed over an approximate 2-year period in order to assess the long-term efficacy of using strain HK44 for monitoring and controlling bioremediation processes. Results showed that P. fluorescens HK44 was capable of surviving initial inoculation into both hydrocarbon contaminated and uncontaminated soils and was recoverable from these soils 660 days post inoculation. It was also demonstrated that strain HK44 was capable of generating bioluminescence in response to soil hydrocarbon bioavailability. Bioluminescence approaching 166,000 counts/s was detected in fiber optic-based biosensor devices responding to volatile polyaromatic hydrocarbons, while a portable photomultiplier module detected bioluminescence at an average of 4300 counts/s directly from soil-borne HK44 cells within localized treatment areas. The utilization of lux-based bioreporter microorganisms therefore promises to be a viable option for in situ determination of environmental contaminant bioavailability and biodegradation process monitoring and control.

  7. Advances in homology directed genetic engineering of human pluripotent and adult stem cells

    PubMed Central

    Ramamoorthi, Kalpith; Curtis, Donald; Asuri, Prashanth

    2013-01-01

    The ability to introduce precise genomic modifications in human cells has profound implications for both basic and applied research in stem cells, ranging from identification of genes regulating stem cell self-renewal and multilineage differentiation to therapeutic gene correction and creation of in vitro models of human diseases. However, the overall efficiency of this process is challenged by several factors including inefficient gene delivery into stem cells and low rates of homology directed site-specific targeting. Recent studies report the development of novel techniques to improve gene targeting efficiencies in human stem cells; these methods include molecular engineering of viral vectors to efficiently deliver episomal genetic sequences that can participate in homology directed targeting, as well as the design of synthetic proteins that can introduce double-stranded breaks in DNA to initiate such recombination events. This review focuses on the potential of these new technologies to precisely alter the human stem cell genome and also highlights the possibilities offered by the combination of these complementary strategies. PMID:24179598

  8. Genetic Engineering Activates Biosynthesis of Aromatic Fumaric Acid Amides in the Human Pathogen Aspergillus fumigatus

    PubMed Central

    Kalb, Daniel; Heinekamp, Thorsten; Lackner, Gerald; Scharf, Daniel H.; Dahse, Hans-Martin; Brakhage, Axel A.

    2014-01-01

    The Aspergillus fumigatus nonribosomal peptide synthetase FtpA is among the few of this species whose natural product has remained unknown. Both FtpA adenylation domains were characterized in vitro. Fumaric acid was identified as preferred substrate of the first and both l-tyrosine and l-phenylalanine as preferred substrates of the second adenylation domain. Genetically engineered A. fumigatus strains expressed either ftpA or the regulator gene ftpR, encoded in the same cluster of genes, under the control of the doxycycline-inducible tetracycline-induced transcriptional activation (tet-on) cassette. These strains produced fumaryl-l-tyrosine and fumaryl-l-phenylalanine which were identified by liquid chromatography and high-resolution mass spectrometry. Modeling of the first adenylation domain in silico provided insight into the structural requirements to bind fumaric acid as peptide synthetase substrate. This work adds aromatic fumaric acid amides to the secondary metabolome of the important human pathogen A. fumigatus which was previously not known as a producer of these compounds. PMID:25527545

  9. Biotechnology and genetic engineering in the new drug development. Part I. DNA technology and recombinant proteins.

    PubMed

    Stryjewska, Agnieszka; Kiepura, Katarzyna; Librowski, Tadeusz; Lochy?ski, Stanis?aw

    2013-01-01

    Pharmaceutical biotechnology has a long tradition and is rooted in the last century, first exemplified by penicillin and streptomycin as low molecular weight biosynthetic compounds. Today, pharmaceutical biotechnology still has its fundamentals in fermentation and bioprocessing, but the paradigmatic change affected by biotechnology and pharmaceutical sciences has led to an updated definition. The biotechnology revolution redrew the research, development, production and even marketing processes of drugs. Powerful new instruments and biotechnology related scientific disciplines (genomics, proteomics) make it possible to examine and exploit the behavior of proteins and molecules. Recombinant DNA (rDNA) technologies (genetic, protein, and metabolic engineering) allow the production of a wide range of peptides, proteins, and biochemicals from naturally nonproducing cells. This technology, now approximately 25 years old, is becoming one of the most important technologies developed in the 20(th) century. Pharmaceutical products and industrial enzymes were the first biotech products on the world market made by means of rDNA. Despite important advances regarding rDNA applications in mammalian cells, yeasts still represent attractive hosts for the production of heterologous proteins. In this review we describe these processes. PMID:24399704

  10. A novel approach for monitoring genetically engineered microorganisms by using artificial, stable RNAs

    NASA Technical Reports Server (NTRS)

    Pitulle, C.; Hedenstierna, K. O.; Fox, G. E.

    1995-01-01

    Further improvements in technology for efficient monitoring of genetically engineered microorganisms (GEMs) in the environment are needed. Technology for monitoring rRNA is well established but has not generally been applicable to GEMs because of the lack of unique rRNA target sequences. In the work described herein, it is demonstrated that a deletion mutant of a plasmid-borne Vibrio proteolyticus 5S rRNA gene continues to accumulate to high levels in Escherichia coli although it is no longer incorporated into 70S ribosomes. This deletion construct was subsequently modified by mutagenesis to create a unique recognition site for the restriction endonuclease BstEII, into which new sequences could be readily inserted. Finally, a novel 17-nucleotide identifier sequence from Pennisetum purpureum was embedded into the construct to create an RNA identification cassette. The artificial identifier RNA, expressed from this cassette in vivo, accumulated in E. coli to levels comparable to those of wild-type 5S rRNA without being seriously detrimental to cell survival in laboratory experiments and without entering the ribosomes. These results demonstrate that artificial, stable RNAs containing sequence segments remarkably different from those present in any known rRNA can be designed and that neither the deleted sequence segment nor ribosome incorporation is essential for accumulation of an RNA product.

  11. Tracking genetically engineered bacteria: monoclonal antibodies against surface determinants of the soil bacterium Pseudomonas putida 2440.

    PubMed Central

    Ramos-González, M I; Ruiz-Cabello, F; Brettar, I; Garrido, F; Ramos, J L

    1992-01-01

    Assessment of potential risks involved in the release of genetically engineered microorganisms is facilitated by the availability of monoclonal antibodies (MAbs), a tool potentially able to monitor specific organisms. We raised a bank of MAbs against the soil bacterium Pseudomonas putida 2440, which is a host for modified TOL plasmids and other recombinant plasmids. Three MAbs, 7.3B, 7.4D, and 7.5D, were highly specific and recognized only P. putida bacteria. Furthermore, we developed a semiquantitative dot blot assay that allowed us to detect as few as 100 cells per spot. A 40-kDa cell surface protein was the target for MAbs 7.4D and 7.5D. Detection of the cell antigen depended on the bacterial growth phase and culture medium. The O antigen of lipopolysaccharide seems to be the target for MAb 7.3B, and its in vivo detection was independent of the bacterial growth phase and culture medium. MAb 7.3B was used successfully to track P. putida (pWW0) released in unsterile lake mesocosms. Images PMID:1373718

  12. Genetically engineered trees for plantation forests: key considerations for environmental risk assessment

    PubMed Central

    Häggman, Hely; Raybould, Alan; Borem, Aluizio; Fox, Thomas; Handley, Levis; Hertzberg, Magnus; Lu, Meng-Zu; Macdonald, Philip; Oguchi, Taichi; Pasquali, Giancarlo; Pearson, Les; Peter, Gary; Quemada, Hector; Séguin, Armand; Tattersall, Kylie; Ulian, Eugênio; Walter, Christian; McLean, Morven

    2013-01-01

    Forests are vital to the world's ecological, social, cultural and economic well-being yet sustainable provision of goods and services from forests is increasingly challenged by pressures such as growing demand for wood and other forest products, land conversion and degradation, and climate change. Intensively managed, highly productive forestry incorporating the most advanced methods for tree breeding, including the application of genetic engineering (GE), has tremendous potential for producing more wood on less land. However, the deployment of GE trees in plantation forests is a controversial topic and concerns have been particularly expressed about potential harms to the environment. This paper, prepared by an international group of experts in silviculture, forest tree breeding, forest biotechnology and environmental risk assessment (ERA) that met in April 2012, examines how the ERA paradigm used for GE crop plants may be applied to GE trees for use in plantation forests. It emphasizes the importance of differentiating between ERA for confined field trials of GE trees, and ERA for unconfined or commercial-scale releases. In the case of the latter, particular attention is paid to characteristics of forest trees that distinguish them from shorter-lived plant species, the temporal and spatial scale of forests, and the biodiversity of the plantation forest as a receiving environment. PMID:23915092

  13. Chemical and genetic engineering strategies to improve the potency of pharmaceutical proteins and enzymes.

    PubMed

    Platis, Dimitris; Labrou, Nikolaos E

    2008-01-01

    Over the last decade there has been significant progress in understanding the molecular basis of disease processes. At the same time the technological advances in the area of genomics and the efforts in proteomics research have increased the possibility of discovering many proteins with defined therapeutic functions. A large number of these proteins have found clinical application. Despite the importance of proteins as therapeutic agents, they have a number of disadvantages in comparison to small-molecule drugs, including immunogenicity and antigenicity, poor efficacy and oral bioavailability as well as, in many cases, short serum half-lives. To date, the most promising approaches for improving protein therapeutics rely on the use of genetic engineering and site-specific chemical synthesis/modification techniques. Improving the potency of protein drugs by employing modern recombinant DNA technologies and novel chemical synthesis techniques is of primary importance, not only because of the enormous medicinal benefit but also because of the significant economic edge an improved drug can provide in today's competitive market. PMID:18691050

  14. Obesity increases tumor aggressiveness in a genetically engineered mouse model of serous ovarian cancer?

    PubMed Central

    Makowski, Liza; Zhou, Chunxiao; Zhong, Yan; Kuan, Pei Fen; Fan, Cheng; Sampey, Brante P.; Difurio, Megan; Bae-Jump, Victoria L.

    2014-01-01

    Objectives Obesity is associated with increased risk and worse outcomes for ovarian cancer. Thus, we examined the effects of obesity on ovarian cancer progression in a genetically engineered mouse model of serous ovarian cancer. Methods We utilized a unique serous ovarian cancer mouse model that specifically deletes the tumor suppressor genes, Brca1 and p53, and inactivates the retinoblastoma (Rb) proteins in adult ovarian surface epithelial cells, via injection of an adenoviral vector expressing Cre (AdCre) into the ovarian bursa cavity of adult female mice (KpB mouse model). KpB mice were subjected to a 60% calories-derived from fat in a high fat diet (HFD) versus 10% calories from fat in a low fat diet (LFD) to mimic diet-induced obesity. Tumors were isolated at 6 months after AdCre injection and evaluated histologically. Untargeted metabolomic and gene expression profiling was performed to assess differences in the ovarian tumors from obese versus non-obese KpB mice. Results At sacrifice, mice on the HFD (obese) were twice the weight of mice on the LFD (non-obese) (51 g versus 31 g, p = 0.0003). Ovarian tumors were significantly larger in the obese versus non-obese mice (3.7 cm2 versus 1.2 cm2, p = 0.0065). Gene expression and metabolomic profiling indicated statistically significant differences between the ovarian tumors from the obese versus non-obese mice, including metabolically relevant pathways. PMID:24680597

  15. Intact soil-core microcosms for evaluating the fate and ecological impact of the release of genetically engineered microorganisms

    SciTech Connect

    Fredrickson, J.K.; Van Voris, P.; Li, S.W. ); Bentjen, S.A. )

    1989-01-01

    Intact soil-core microcosms were studied to determine their applicability for evaluating the transport, survival, and potential ecosystem effects of genetically engineered microorganisms before they are released into the environment. Soil-core microcosms were planted with wheat and maize seeds and inoculated with Azospirillum lipoferum SpBr17 and SpRG20a Tn5 mutants, respectively. Microcosm leachate, rhizosphere soil, plant endorhizosphere, insects, and xylem exudate were sampled for A. lipoferum Tn5 mutant populations. A. lipoferum TN5 populations, determined by most-probable-number technique-DNA hybridization, varied from bellow detection to 10{sup 6} g of dry root{sup {minus}1} in the rhizosphere, with smaller populations detected in the endorhizosphere. Intact soil-core microcosms were found to maintain some of the complexities of the natural ecosystem and should be particularly useful for initial evaluations of the fate of plant-associated genetically engineered bacteria.

  16. Characterization of the most abundant Lactobacillus species in chicken gastrointestinal tract and potential use as probiotics for genetic engineering.

    PubMed

    Wang, Lei; Fang, Mingjian; Hu, Yanping; Yang, Yuxin; Yang, Mingming; Chen, Yulin

    2014-07-01

    The count and diffusion of Lactobacilli species in the different gastrointestinal tract (GI) regions of broilers were investigated by quantitative real-time polymerase chain reaction, and the probiotic characteristics of six L. reuteri species isolated from broilers' GI tract were also investigated to obtain the potential target for genetic engineering. Lactobacilli had the highest diversity in the crop and the lowest one in the cecum. Compared with the lower GI tract, more Lactobacilli were found in the upper GI tract. Lactobacillus reuteri, L. johnsonii, L. acidophilus, L. crispatus, L. salivarius, and L. aviarius were the predominant Lactobacillus species and present throughout the GI tract of chickens. Lactobacillus reuteri was the most abundant Lactobacillus species. Lactobacillus reuteri XC1 had good probiotic characteristics that would be a potential and desirable target for genetic engineering. PMID:24850302

  17. Multiple amino acid-excluded genetic codes for protein engineering using multiple sets of tRNA variants.

    PubMed

    Amikura, Kazuaki; Sakai, Yoko; Asami, Shun; Kiga, Daisuke

    2014-03-21

    A "simplified genetic code", with only 19 amino acids assigned to the sense codons, was recently developed. In this study, we describe novel simplified codes in which multiple amino acids are simultaneously excluded from the universal code. In the simplest code, tryptophan, cysteine, tyrosine, and asparagine codons are assigned to serine by using four kinds of tRNA (Ser) variants. The results revealed that various sets of amino acids can easily be excluded from the universal code, using our strategy for genetic code simplification. A simplified genetic code is useful as an engineering tool for the improvement of industrial enzymes and pharmaceuticals, and also provides new insights into the assessment of protein evolution. Simplified codes in which multiple amino acids are simultaneously excluded from the code can be more effective tools than codes excluding only one amino acid. PMID:24256181

  18. Biocatalytic Lactone Generation in Genetically Engineered Escherichia coli and Identification of Products by Gas Chromatography-Mass Spectroscopy

    NASA Astrophysics Data System (ADS)

    Slawson, Chad; Stewart, Jon; Potter, Robert

    2001-11-01

    Genetically altered Escherichia coli are used as biocatalysts to produce optically pure lactones from a variety of cyclic ketones as a biotechnology experiment for a biochemistry laboratory. The genetically engineered E. coli bacteria express large amounts of the enzyme cyclohexanone monooxygenase and are therefor capable of converting a variety of ketones into optically pure lactones. Separation by organic extraction and analysis by thin layer chromatography and gas chromatography-mass spectroscopy allows for the direct identification of products. Yield calculations and evaluation of the cost effectiveness of various substrates give students an opportunity to make recommendations and model industrial decision-making. Evaluation of the synthetic process for its environmental impact allows students to consider problems of cost versus environmental concerns. Use of bacterial biocatalysts offers chemistry students an opportunity to work with microorganisms and directly see the utility of genetically altered bacteria for synthetic chemistry.

  19. Engineered sensors and genetic regulatory networks for control of cellular metabolism

    E-print Network

    Moser, Felix, Ph. D. Massachusetts Institute of Technology

    2013-01-01

    Complex synthetic genetic programs promise unprecedented control over cellular metabolism and behavior. In this thesis, I describe the design and development of a synthetic genetic program to detect conditions underlying ...

  20. Can Man Control His Biological Evolution? A Symposium on Genetic Engineering. Man's Responsibility to His Future

    ERIC Educational Resources Information Center

    Hoagland, Hudson

    1972-01-01

    Biological evolution can be carried out in the laboratory. With new knowledge available in genetics, possibilities are raised that genetic characters can be transferred in the future to embryos according to a predetermined plan. (PS)