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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Assessment of Murine Embryo Development Following Electroporation and Microinjection of a Green Fluorescent Protein DNA Construct

Schmotzer, Carolyn Anne 06 August 2001 (has links)
Transgenic techniques have rapidly evolved in recent years. However, the efficiency of these techniques to produce viable offspring is still disappointingly low. The purpose of this study was to assess in vitro development, transgene expression, and integration following pronuclear or cytoplasmic microinjection of condensed or linear green fluorescent protein DNA into murine embryos using electroporation. In experiment 1, the effect of embryo orientation (group or linear) within the electroporation chamber on development was evaluated using zygotes which received one pulse duration (10 msec), and one of two voltages (250 or 400 V). Zygotes that received 400 V had the lowest development score (Group, 2.06 ? 0.12; Linear, 1.97 ? 0.13), irrespective of orientation. Embryos that received 250 V had the highest development of the voltage treated groups (Group 3.42 ? 0.12; Linear 3.32 ? 0.12), irrespective of orientation, and development was lower than the control embryos (Control 4.28 ? 0.12; Mannitol control 4.36 ? 0.18). In experiment 2, the efficiency of utilization of the prepared enhanced green fluorescent protein (EGFP) construct as a visual marker of protein expression was evaluated using pronuclear microinjection. Embryo development and fluorescence were evaluated following pronuclear injection of EGFP at a concentration of 3 μg/ml and compared to an uninjected control. Embryos injected with the EGFP had lower development scores (3.85 ± 0.15) than uninjected control embryos (5.72 ± 0.2). Of the embryos injected, 32.4% fluoresced due to expression of EGFP. Experiment 3 evaluated the effect of combining cytoplasmic injection of EGFP (425 μg/ml) with electroporation at 250 V on EGFP expression. The non-manipulated control embryos had significantly higher (P < 0.01) 4 d development scores (5.57 ± 0.11) than manipulated control embryos (4.6 ± 0.18), where the injection needle was inserted into the cytoplasm and no DNA was injected. Combining cytoplasmic DNA injection and electroporation caused a significant (P < 0.01) decrease in development scores, irrespective of DNA construct, when compared to embryos injected with a DNA construct alone. The mechanical effects of needle insertion combined with electroporation were not significantly different (P > 0.05) from embryos injected with DNA alone, irrespective of construct injected. Cytoplasmic injection of condensed DNA (0.38%), linear DNA (0.38%), and condensed DNA combined with electroporation (0.36%) resulted in one fluorescent embryo respectively. Cytoplasmic injection of linear DNA when combined with electroporation (3.57%) resulted in 13 fluorescent embryos. Pronuclear injection of the prepared EGFP construct results in lower development than control embryos. Electrical stimulation of zygotes reduces early embryo development. However, low amounts of electrical stimulation may allow for enhancement of gene integration in transgenic embryos. / Master of Science
12

Self-assembly of temperature-responsive protein–polymer bioconjugates

Moatsou, D., Li, J., Ranji, A., Pitto-Barry, Anaïs, Ntai, I., Jewett, M.C., O'Reilley, R.K. 17 June 2016 (has links)
Yes / We report a simple temperature-responsive bioconjugate system comprising superfolder green fluorescent protein (sfGFP) decorated with poly[(oligo ethylene glycol) methyl ether methacrylate] (PEGMA) polymers. We used amber suppression to site-specifically incorporate the non-canonical azide-functional amino acid p-azidophenylalanine (pAzF) into sfGFP at different positions. The azide moiety on modified sfGFP was then coupled using copper-catalyzed “click” chemistry with the alkyne terminus of a PEGMA synthesized by reversible addition–fragmentation chain transfer (RAFT) polymerization. The protein in the resulting bioconjugate was found to remain functionally active (i.e., fluorescent) after conjugation. Turbidity measurements revealed that the point of attachment of the polymer onto the protein scaffold has an impact on the thermoresponsive behavior of the resultant bioconjugate. Furthermore, small-angle X-ray scattering analysis showed the wrapping of the polymer around the protein in a temperature-dependent fashion. Our work demonstrates that standard genetic manipulation combined with an expanded genetic code provides an easy way to construct functional hybrid biomaterials where the location of the conjugation site on the protein plays an important role in determining material properties. We anticipate that our approach could be generalized for the synthesis of complex functional materials with precisely defined domain orientation, connectivity, and composition. / Engineering and Physical Sciences Research Council (EPSRC), University of Warwick, National Science Foundation (U.S.) (NSF), United States. Defense Advanced Research Projects Agency (DARPA), Seventh Framework Programme (European Commission) (FP7), European Research Council (ERC)
13

Crystallographic and spectroscopic studies of photoswitching in fluorescent proteins /

Henderson, Julius Nathan. January 2007 (has links)
Thesis (Ph. D.)--University of Oregon, 2007. / Typescript. Includes vita and abstract. Includes bibliographical references (leaves 143-151). Also available for download via the World Wide Web; free to University of Oregon users.
14

Subcellular localization of GFP fusions with the seven vacuolar sorting receptors of Arabidopsis thaliana to prevacuolar compartments in transgenic tobacco BY-2 cells.

January 2006 (has links)
Miao Yansong. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (leaves 78-83). / Abstracts in English and Chinese. / Thesis/Assessment Committee --- p.ii / Statement --- p.iii / 摘要 --- p.vi / Acknowledgements --- p.vii / List of Tables --- p.xi / List of Figures --- p.xii / List of Abbreviations --- p.xiv / Chapter Chapter 1 --- General Introduction --- p.1 / Chapter 1. --- The plant secretory pathway --- p.2 / Chapter 2. --- Two different types of vacuoles in plant cells --- p.2 / Chapter 3. --- Vacuolar sorting receptor (VSR) proteins --- p.3 / Chapter 4. --- BP-80 and prevacuolar compartment --- p.6 / Chapter 5. --- The Arabidopsis VSR proteins --- p.7 / Chapter 6. --- Research objectives --- p.8 / Chapter Chapter 2 --- Development of Transgenic Tobacco BY-2 Cell Lines Expressing GFP-AtVSR Fusions --- p.10 / Chapter 1. --- Introduction --- p.11 / Chapter 2. --- Materials and Methods --- p.12 / Chapter 2.1 --- Structure of Golgi marker and PVC marker --- p.12 / Chapter 2.2 --- Construction of GFP-VSR reporters --- p.14 / Chapter 2.3 --- Agrobacterium electroporation --- p.24 / Chapter 2.4 --- Transformation of tobacco BY-2 cells --- p.24 / Chapter 2.5 --- Screening of transgenic BY-2 cells expressing GFP-VSR fusions --- p.25 / Chapter 2.6 --- Chemicals --- p.27 / Chapter 3. --- Result.s --- p.28 / Chapter 3.1 --- Chimeric GFP reporters as tools to study subcellular localization of Arabidopsis vacuolar sorting receptor proteins in transgenic BY-2 cells --- p.28 / Chapter 3.2 --- Establishment of transgenic tobacco (Nicotiana tabacum) BY-2 cell lines stably expressing seven GFP-AtVSR reporters --- p.29 / Chapter 4. --- Conclusion --- p.38 / Chapter Chapter 3 --- Subcellular Localization of the Seven GFP-AtVSR Fusions to Prevacuolar Compartments in Transgenic Tobacco BY-2 Cells --- p.39 / Chapter 1. --- Introduction --- p.40 / Chapter 2. --- Materials and Methods --- p.41 / Chapter 2.1 --- Confocal immunofluorescence studies --- p.41 / Chapter 2.2 --- Antibodies for immunolabeling --- p.42 / Chapter 2.3 --- Wortmannin and brefeldin A treatment --- p.42 / Chapter 2.4 --- Electron microscopy of resin-embedded cells --- p.43 / Chapter 3. --- Results --- p.44 / Chapter 3.1 --- Vacuolar sorting receptor proteins in plants --- p.44 / Chapter 3.2 --- PVC localization of GFP-AtVSR fusions in transgenic tobacco BY-2 cells --- p.47 / Chapter 3.3 --- The spacer sequences did not affect PVC localization of GFP-AtVSR7 --- p.56 / Chapter 3.4 --- Wortmannin-induced vacuolated PVCs contained VSRs in tobacco BY-2 cells --- p.58 / Chapter 3.5 --- Wortmannin-induced vacuolation of PVCs is a general response in plant cells --- p.62 / Chapter 4. --- Conclusion --- p.65 / Chapter Chapter 4 --- Discussion and Future Perspectives --- p.66 / Chapter 1. --- The hypothesis in this study --- p.67 / Chapter 2. --- GFP and BY-2 cells --- p.67 / Chapter 3. --- A reporter system to study subcellular localization of VSR proteins in transgenic tobacco BY-2 cells --- p.68 / Chapter 4. --- PVC localization of the seven GFP-AtVSR fusions in transgenic BY-2 cells --- p.69 / Chapter 5. --- VSR spacer sequences did not affect PVC localization of GFP-AtVSR fusions in transgenic tobacco BY-2 cells --- p.71 / Chapter 6. --- PVC localization of GFP-PV72 and GFP-AtVSR 1 fusions in transgenic tobacco BY-2 cells --- p.73 / Chapter 7. --- Wortmannin-induced vacuolation of PVC is a general response in plant cells --- p.75 / Chapter 8. --- Future perspectives --- p.75 / References --- p.78
15

Root colonization and environmental fate of the bioherbicide pseudomonas fluorescens

Hanson, Caressa 22 September 2008
<i>Pseudomonas fluorescens</i> BRG100 produces secondary metabolites with herbicidal activity to the grass weeds wild oat, Avena fatua, and green foxtail, Setaria viridis. The green fluorescence protein (gfp) gene was introduced into P. fluorescens BRG100 from Escherichia coli S17-1¥ë via a Tn5 mini transposon suicide vector system. Colony morphology, growth rate in liquid media, weed biocontrol efficacy (plant growth pouch), carbon utilization (Biolog GN) and root colonization of green foxtail by several P. fluorescens BRG100gfp transformants were determined to be the same as the wild type. <i>Pseudomonas fluorescens</i> BRGgfp-15 was found to be most similar to the wild-type in all of the above characteristics and was thus used in subsequent experiments. Note: all strains of Pseudomonas fluorescens will be referred to by only their strain throughout (ie. BRGgfp-15 and BRG100). <p>It was determined by population dynamics per section of root with spiral plating on culture medium, epi-fluorescence and confocal microscopy that BRGgfp-15 colonized all areas of the root, but showed a preference for the proximal 1/3 section and the seed. In the proximal section the mean number of viable cells per gram dry weight was log109.06 and log109.31, when applied as liquid inoculum and as the pesta granular formulation, respectively. With liquid inoculum there was only log107.53 viable cells/g in the middle 1/3 section and log107.01 viable cells/g in the distal 1/3 section. The number of viable cells/g with pesta granules was log107.61 and log107.34, for the middle and distal sections, respectively. The root hairs, root tip, and ventral portion of the seed were all areas of heavy colonization relative to the other areas of the root. <p>Survival of BRGgfp-15 in the pesta formulation was examined in 2 soil types, clay and clay loam, in a thermogradient plate apparatus by a factorial randomized design complete block experiment. The experiment included: 3-12 hour diurnal temperature regimes: 5-15¨¬C, 15-25¨¬C, and 25-35¨¬C and 3 moisture levels: 25, 50 and 75% of soil moisture holding capacity. Sampling was carried out after 0, 14, 28 and 42 days. The highest numbers of viable BRGgfp-15 cells/g were found in the pesta granules in soil subjected to the lowest diurnal temperature regime and moisture content. The lowest numbers of viable cells/g were found in the pesta granules incubated in the highest diurnal temperature and moisture. This suggests lower soil temperature and moisture enhances survival of BRGgfp-15 in pesta and/ or higher soil temperature and moisture enhances the release and dissemination of BRGgfp-15 from pesta granules. When subjected to a 5-15¨¬C-temperature regime the number of viable cells/g was log109.80. When subjected to 15-25¨¬C the viable cells/g was log108.96 and with 25-35¨¬C it was log107.33. The mean number of viable cells/g was log109.36, log108.86, and log107.87, for 25, 50, and 75% soil moisture holding capacity, respectively. There was also a significantly higher number of viable cells/g in the clay soil collected from Saskatoon, log109.00, as compared to the clay loam soil collected from Scott, which was log108.40. <p>These results suggest that Pseudomonas fluorescens BRG100 has considerable potential as a bioherbicide because of its successful root colonization of green foxtail and wheat. <i>Pseudomonas fluorescens</i> BRGgfp-15 survived well under various environmental conditions when formulated into pesta granules, proving the pesta formulation was an excellent formulation. In addition, gfp was shown to be an excellent conservative marker for monitoring the root colonization and survival of <i>P. fluorescens</i> BRG100.
16

Root colonization and environmental fate of the bioherbicide pseudomonas fluorescens

Hanson, Caressa 22 September 2008 (has links)
<i>Pseudomonas fluorescens</i> BRG100 produces secondary metabolites with herbicidal activity to the grass weeds wild oat, Avena fatua, and green foxtail, Setaria viridis. The green fluorescence protein (gfp) gene was introduced into P. fluorescens BRG100 from Escherichia coli S17-1¥ë via a Tn5 mini transposon suicide vector system. Colony morphology, growth rate in liquid media, weed biocontrol efficacy (plant growth pouch), carbon utilization (Biolog GN) and root colonization of green foxtail by several P. fluorescens BRG100gfp transformants were determined to be the same as the wild type. <i>Pseudomonas fluorescens</i> BRGgfp-15 was found to be most similar to the wild-type in all of the above characteristics and was thus used in subsequent experiments. Note: all strains of Pseudomonas fluorescens will be referred to by only their strain throughout (ie. BRGgfp-15 and BRG100). <p>It was determined by population dynamics per section of root with spiral plating on culture medium, epi-fluorescence and confocal microscopy that BRGgfp-15 colonized all areas of the root, but showed a preference for the proximal 1/3 section and the seed. In the proximal section the mean number of viable cells per gram dry weight was log109.06 and log109.31, when applied as liquid inoculum and as the pesta granular formulation, respectively. With liquid inoculum there was only log107.53 viable cells/g in the middle 1/3 section and log107.01 viable cells/g in the distal 1/3 section. The number of viable cells/g with pesta granules was log107.61 and log107.34, for the middle and distal sections, respectively. The root hairs, root tip, and ventral portion of the seed were all areas of heavy colonization relative to the other areas of the root. <p>Survival of BRGgfp-15 in the pesta formulation was examined in 2 soil types, clay and clay loam, in a thermogradient plate apparatus by a factorial randomized design complete block experiment. The experiment included: 3-12 hour diurnal temperature regimes: 5-15¨¬C, 15-25¨¬C, and 25-35¨¬C and 3 moisture levels: 25, 50 and 75% of soil moisture holding capacity. Sampling was carried out after 0, 14, 28 and 42 days. The highest numbers of viable BRGgfp-15 cells/g were found in the pesta granules in soil subjected to the lowest diurnal temperature regime and moisture content. The lowest numbers of viable cells/g were found in the pesta granules incubated in the highest diurnal temperature and moisture. This suggests lower soil temperature and moisture enhances survival of BRGgfp-15 in pesta and/ or higher soil temperature and moisture enhances the release and dissemination of BRGgfp-15 from pesta granules. When subjected to a 5-15¨¬C-temperature regime the number of viable cells/g was log109.80. When subjected to 15-25¨¬C the viable cells/g was log108.96 and with 25-35¨¬C it was log107.33. The mean number of viable cells/g was log109.36, log108.86, and log107.87, for 25, 50, and 75% soil moisture holding capacity, respectively. There was also a significantly higher number of viable cells/g in the clay soil collected from Saskatoon, log109.00, as compared to the clay loam soil collected from Scott, which was log108.40. <p>These results suggest that Pseudomonas fluorescens BRG100 has considerable potential as a bioherbicide because of its successful root colonization of green foxtail and wheat. <i>Pseudomonas fluorescens</i> BRGgfp-15 survived well under various environmental conditions when formulated into pesta granules, proving the pesta formulation was an excellent formulation. In addition, gfp was shown to be an excellent conservative marker for monitoring the root colonization and survival of <i>P. fluorescens</i> BRG100.
17

Establishment of GFP-expressing porcine embryonic stem cell lines and application there of in the rat Parkinson¡¦s disease model

Yang, Jenn-rong 16 June 2009 (has links)
Stem cells have the ability to reproduce themselves for a long period and differentiate into specific morphological and functional cells. The stem cells are an important material in the developmental biology, genomics, and transgenic methods, as well as in potential clinical applications, gene therapy and tissue engineering. The pluripotent stem cells will be a valuable source in numerous functional degenerated pathologies. Therefore, the objective of this research program was to establish transgenic porcine embryonic stem (pES) cell lines which can express green fluorescent protein (GFP) report gene stably for tracking after transplantation. We also developed a directed differentiation of pES into neural lineages and applied in rat Parkinson¡¦s disease model. Although the establishment of pluripotent ES cell lines from domestic species is much more difficult than that in murine species, our results had successfully isolated and established pES cell lines from pre-implantation blastocysts. Furthermore, we established the novel GFP-expressing pES cell lines (pES/GFP+), which were obtained by electroporation- mediated transfection with exogenous GFP gene. These pES/GFP+ cells exhibited pluripotent markers including Oct-4, AP, SSEA-4, TRA-1-60, and TRA-1-81 as that of human ES cells. The strategy of directed neural differentiation was to culture pES with neurogenic stimulators such as retinoic acid (RA), sonic hedgehog (SHH), and fibroblast growth factor (FGF). Upon directed differentiation toward neural differentiation, these pES-derived cells exhibited typical neuronal morphology and expressed neural lineage-specific markers such as nestin, NFL, MAP2, GFAP, A2B5, TH, ChAT, and GABA. These results showed the pES cells had the potential to differentiate into neural lineages. When pES/GFP+ cells were transplanted into the SD rat¡¦s brain, and their survival and development was determined by the non-invasive In Vivo Imaging System (IVIS 50), and the invasive fibered confocal Cellvizio® Imaging System (Cellvizio®). The results showed that fluorescent signals from pES/GFP+ cells on the injection site of SD rats¡¦ brain could be detected through the experimental period of 3 months. The level of fluorescent signals detected in treatment groups was two folds above that of the control group. Besides, the functional behavior recovery analysis by amphetamine-induced rotation test indicated the PD rat grafted with pES/GFP+ cells and their derived neural progenitors showed no significant recovery of rotation rate in these two treatments because a progressively increased relative rotation through 3 months duration. However, the relative rotation of PD rats grafted with the pES/GFP+-derived mature neurons, showed a stably decrease relative rotation and resulted in a functional recovery from Parkinsonian behavioral defects. Following 3 months completion of behavioral analyses, PD rats were sacrificed for immunohistochemical analysis. In the section of injected site without tumorgenesis and showed the survival and dopaminergic differentiation of grafted pES/GFP+ derived cells when stained with anti-TH and anti-DA. To our knowledge, there have been no reports of establishing GFP-expressing pES cell lines. These novel pES/GFP+ cell lines established in this study might serve as a non-rodent model and could benefit to the studies involving ES cell transplantation, cell replacement therapy, tissue regeneration, and actual approach for pre-clinical research due to their traceable capacity.
18

Synthesis, photophysics, and application of fluorescent protein chromophore analogs

Baldridge, Anthony Owen 19 May 2011 (has links)
The green fluorescent protein chromophore exhibits remarkably different properties upon removal from the protective beta-barrel. This work focuses on the synthesis of these chromophores as wells studying the photophysics as to why they readily deactivate. Following these initial discoveries, these chromophores can be applied to many different environments providing a fluorescence "turn-on" and thus proving to be applicable in a number of different environments and fields.
19

Chloroplast GFP expression in tobacco plants agroinfiltrated with tobacco mosaic virus based vectors

Tah, Tapashree. Schoelz, James E. January 2009 (has links)
Title from PDF of title page (University of Missouri--Columbia, viewed on Feb 19, 2010). The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Thesis advisor: Dr. James E. Schoelz. Includes bibliographical references.
20

Photophysics of emission color in flourescent proteins /

Shu, Xiaokun. January 2007 (has links)
Thesis (Ph. D.)--University of Oregon, 2007. / Typescript. Includes vita and abstract. Includes bibliographical references (leaves 176-185). Also available for download via the World Wide Web; free to University of Oregon users.

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