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Sample records for sars-cov gfp sars-cov

  1. Bioinformatics analysis of SARS-Cov M protein provides information for vaccine development

    Institute of Scientific and Technical Information of China (English)

    LIU Wanli; LU Yun; CHEN Yinghua

    2003-01-01

    The pathogen causing severe acute respiratory syndrome (SARS) is identified to be SARS-Cov. It is urgent to know more about SARS-Cov for developing an efficient SARS vaccine to prevent this epidemic disease. In this report, the homology of SARS-Cov M protein to other members of coronavirus is illustrated, and all amino acid changes in both S and M proteins among all available SARS-Cov isolates in GenBank are described. Furthermore, one topological trans-membrane secondary structure model of M protein is proposed, which is corresponded well with the accepted topology model of M proteins of other members of coronavirus. Hydrophilic profile analysis indicated that one region (aa150~210) on the cytoplasmic domain is fairly hydrophilic, suggesting its property of antigenicity. Based on the fact that cytoplasmic domain of the M protein of some other coronavirus could induce protective activities against virus infection, this region might be one potential target for SARS vaccine development.

  2. Receptor-binding domain of SARS-Cov spike protein: Soluble expression in purification and functional characterization

    Institute of Scientific and Technical Information of China (English)

    Jing Chen; Lin Miao; Jia-Ming Li; Yan-Ying Li; Qing-Yu Zhu; Chang-Lin Zhou; Hong-Qing Fang; Hui-Peng Chen

    2005-01-01

    AIM: To find a soluble and functional recombinant receptor-binding domain of severe acute respiratory syndrome-associated coronavirus (SARS-Cov), and to analyze its receptor binding ability.METHODS: Three fusion tags (glutathione S-transferase,GST; thioredoxin, Trx; maltose-binding protein, MBP),which preferably contributes to increasing solubility and to facilitating the proper folding of heteroprotein, were used to acquire the soluble and functional expression of RBD protein in Escherichia coli( BL21( DE3 ) and Rosetta-gamiB(DE3) strains). The receptor binding ability of the purified soluble RBD protein was then detected by ELISA and flow cytometry assay.RESULTS: RBD of SARS-Cov spike protein was expressed as inclusion body when fused as TrxA tag form in both BL21 (DE3) and Rosetta-gamiB (DE3) under many different cultures and induction conditions. And there was no visible expression band on SDS-PAGE when RBD was expressed as MBP tagged form. Only GST tagged RBD was soluble expressed in BL21(DE3), and the protein was purified by AKTA Prime Chromatography system. The ELISA data anti-RBD mouse monoclonal antibody 1A5. Further flow cytometry assay demonstrated the high efficiency of RBD's binding ability to ACE2 (angiotensin-converting enzyme 2)positive Vero E6 cell. And ACE2 was proved as a cellular receptor that meditated an initial-affinity interaction with SARS-Cov spike protein. The geometrical mean of GST and respectively.CONCLUSION: In this paper, we get sufficient soluble N terminal GST tagged RBD protein expressed in E. coli BL21(DE3); data from ELISA and flow cytometry assay demonstrate that the recombinant protein is functional and binding to ACE2 positive Vero E6 cell efficiently. And the recombinant RBD derived from E. coli can be used to developing subunit vaccine to block S protein binding with receptor and to neutralizing SARS-Cov infection.

  3. DNA Vaccine of SARS-Cov S Gene Induces Antibody Response in Mice

    Institute of Scientific and Technical Information of China (English)

    PingZHAO; Jin-ShanKE; Zhao-LinQIN; HaoREN; Lan-JuanZHAO; Jian-GuoYU

    2004-01-01

    The spike (S) protein, a main surface antigen of SARS-coronavirus (SARS-CoV), is one of the most important antigen candidates for vaccine design. In the present study, three fragments of the truncated S protein were expressed in E.coli, and analyzed with pooled sera of convalescence phase of SARS patients.The full length S gene DNA vaccine was constructed and used to immunize BALB/c mice. The mouse serum IgG antibody against SARS-CoV was measured by ELISA with E.coli expressed truncated S protein or SARS-CoV lysate as diagnostic antigen. The results showed that all the three fragments of S protein expressed by E.coli was able to react with sera of SARS patients and the S gene DNA candidate vaccine could induce the production of specific IgG antibody against SARS-CoV efficiently in mice with seroconversion ratio of 75% after 3 times of immunization. These findings lay some foundations for further understanding the immunology of SARS-CoV and developing SARS vaccines.

  4. DNA Vaccine of SARS-Cov S Gene Induces Antibody Response in Mice

    Institute of Scientific and Technical Information of China (English)

    Ping ZHAO; Jin-Shan KE; Zhao-Lin QIN; Hao REN; Lan-Juan ZHAO; Jian-Guo YU; Jun GAO; Shi-Ying ZHU; Zhong-Tian QI

    2004-01-01

    The spike (S) protein, a main surface antigen of SARS-coronavirus (SARS-CoV), is one of the most important antigen candidates for vaccine design. In the present study, three fragments of the truncated S protein were expressed in E. Coli, and analyzed with pooled sera of convalescence phase of SARS patients.The full length S gene DNA vaccine was constructed and used to immunize BALB/c mice. The mouse serum IgG antibody against SARS-CoV was measured by ELISA with E. Coli expressed truncated S protein or SARS-CoV lysate as diagnostic antigen. The results showed that all the three fragments of S protein expressed by E. Coli was able to react with sera of SARS patients and the S gene DNA candidate vaccine could induce the production of specific IgG antibody against SARS-CoV efficiently in mice with seroconversion ratio of 75% after 3 times of immunization. These findings lay some foundations for further understanding the immunology of SARS-CoV and developing SARS vaccines.

  5. CLONING SEGMENT SPIKE PROTEIN GENE OF SARS-COV AND ITS EXPRESSION IN ESCHERICHIA COLI

    Institute of Scientific and Technical Information of China (English)

    刘中华; 许文波; 毛乃颖; 张燕; 朱贞; 崔爱利; 杨建国; 胡海涛

    2004-01-01

    Objective Expressing and purifying the segment of SARS-CoV spike protein in E.Coli. Methods The target gene was obtained by RT-PCR. The PCR product was cloned into pEGM- T Easy Vector, sequencing and double restriction digestion ( BamHⅠ,PstⅠ) were performed. The target gene was subcloned into PQE30 expression vector. The gene was expressed in the E.coli strain M15 cells induced by IPTG. The protein was purified with a nickel HiTrap chelating metal affinity column. Results The recombinant expression plasmid was successfully constructed and the protein was well expressed in E. coli strain M15 cells. The ideal pure protein was obtained by purification. Western blotting analysis suggested the protein could act with the convalescent sera of lab confirmed SARS patients. Conclusion The segment of SARS-CoV spike protein was well expressed and purified, and can be applied in diagnosis and immunological research of SARS.

  6. Reconstruction of the most recent common ancestor sequences of SARS-Cov S gene and detection of adaptive evolution in the spike protein

    Institute of Scientific and Technical Information of China (English)

    ZHANG Yuan; ZHENG Nan; HAO Pei; ZHONG Yang

    2004-01-01

    @@ The genome organization and expression strategy of severe acute respiratory syndrome coronavirus (SARSCoV) have been described extensivelyl1- 10]. As a structural glycoprotein on the virion surface, the spike protein is responsible for binding to host cellular receptors and for the fusion between the viral envelope and the cellular membrane. It also induces neutralizing antibodies in the host and mediates cellular immunity[11]. Previous studies suggested that amino acid replacements in the spike protein could dramatically alter the pathogenesis and virulence of some coronaviruses[11]. It is therefore reasonable to test the hypothesis that radical amino acid replacements in the spike protein, favored by environmental selective pressure during the process of SARS-CoV interspecific transmission[10], might make this pathogen adapt to a new host. In this study, we investigated a total of 108complete sequences of the SARS-CoV S gene from GenBank (until March 23, 2004). After omission of those records containing frame-shift mutations or low quality sequences, e.g. ZJ01, and selection of one sequence for identical records, an alignment of 42 sequences was obtained using the program Clustal-X[13]. Then, we reconstructed the most recent common ancestor (MRCA) sequences of the SARS-CoV S gene and detected the adaptive evolution in the spike protein.

  7. GFP

    African Journals Online (AJOL)

    Esayas G

    2012-05-03

    May 3, 2012 ... localization as a green fluorescent protein (GFP) fusion in caco-2 cell line .... analyzed using Vector NTI software (Invitrogen Vector NTI. AdvanceTM10 ..... sequences of the sequenced four human Dectin-1 iso- form transcripts ...

  8. GFP as potential cellular viscosimeter

    Science.gov (United States)

    Visser, Antonie J. W. G.; Westphal, Adrie H.; Skakun, Victor V.; Borst, Jan Willem

    2016-09-01

    The molecular dimensions of proteins such as green fluorescent protein (GFP) are large as compared to the ones of solvents like water or glycerol. The microscopic viscosity, which determines the resistance to diffusion of, e.g. GFP, is then the same as that determined from the resistance of the solvent to flow, which is known as macroscopic viscosity. GFP in water/glycerol mixtures senses this macroscopic viscosity, because the translational and rotational diffusion coefficients are proportional to the reciprocal value of the viscosity as predicted by the Stokes-Einstein equations. To test this hypothesis, we have performed time-resolved fluorescence anisotropy (reporting on rotational diffusion) and fluorescence correlation spectroscopy (reporting on translational diffusion) experiments of GFP in water/glycerol mixtures. When the solvent also contains macromolecules of similar or larger dimensions as GFP, the microscopic and macroscopic viscosities can be markedly different and the Stokes-Einstein relations must be adapted. It was established from previous dynamic fluorescence spectroscopy observations of diffusing proteins with dextran polysaccharides as co-solvents (Lavalette et al 2006 Eur. Biophys. J. 35 517-22), that rotation and translation sense a different microscopic viscosity, in which the one arising from rotation is always less than that from translation. A microscopic viscosity parameter is defined that depends on scaling factors between GFP and its immediate environment. The direct consequence is discussed for two reported diffusion coefficients of GFP in living cells.

  9. [Prokaryotic expression of S2 extracellular domain of SARS coronavirus spike protein and its fusion with Hela cell membrane].

    Science.gov (United States)

    Liu, Yun; Liu, Ai-Hua; Deng, Peng; Wu, Xiang-Ling; Li, Tao; Liu, Ya-Wei; Xu, Jia; Jiang, Yong

    2009-03-01

    To construct the expression plasmid of S2 extracellular domain (S2ED) of SARS-coronavirus (SARS- Cov) spike protein (S protein) and enhanced green fluorescent protein (EGFP) to obtain the fusion protein expressed in prokaryotic cells. S2ED based on bioinformatics prediction and EGFP sequence were amplified by PCR and inserted into pET-14b plasmid. The recombinant protein His-S2ED-EGFP was expressed in E. coli by IPTG induction. After purification by Ni-NTA agarose beads, the soluble fractions of the fusion protein were collected and identified by SDS-PAGE and Western blotting. The fusion of S2ED with Hela cell membranes was observed with fluorescent microscope. The pET-14b-S2ED-EGFP plasmid was correctly constructed and highly expressed in BL21 (DE3). When incubated with Hela cells, the purified protein could not internalize through membrane fusion. The expression plasmid containing S2ED of SARS-Cov S protein and EGFP sequence is constructed successfully. Although the recombinant protein obtained has not shown the expected fusion effect with Hela cell membrane, this work may enrich the understanding of the process of membrane fusion mediated by S2 protein and lay the foundation for future study of targeting cell transport system based on cell-specific binding peptide.

  10. GFP Bunny: a coelhinha transgênica

    Directory of Open Access Journals (Sweden)

    Eduardo Kac

    2008-11-01

    Full Text Available GFP Bunny é um trabalho de arte transgênica que compreende a criação de um coelho verde fluorescente por meio da proteí­na que lhe confere essa cor, o diálogo público gerado pelo projeto e a integração social da coelha. GFP Bunny foi realizado em 2000 e apresentado publicamente pela primeira vez em Avignon, França. Esse trabalho foi proposto como uma nova forma de arte decorrente do uso de engenharia genéticana transferência de genes naturais ou sintéticos para um organismo com o objetivo de criar seres vivos únicos. Um trabalho que requer o máximo de cuidado, de consciência do grau de complexidade das questões que ele provoca e, acima de tudo, de compromisso para respeitar, cuidar e amar a vida criada.Abstract: GPF Bunny is a trasgenic artwork comprises the creation of a green fluorescent rabbit, its social integration, and the ensuing public debate. GFP Bunny was realized in 2000 and first presented publicity in Avignon, France. This work was proposed as a newart form based on the use of genetic engineering to transfer natural or synthetic genes to an organism, to create unique living beings. This must be done with great care, with acknowledgment of the complex issues thus raised and, above all, with a commitment to respect, nurture, and love the life thus created.

  11. Establishment of oct4:gfp transgenic zebrafish line for monitoring cellular multipotency by GFP fluorescence.

    Science.gov (United States)

    Kato, Hiroyuki; Abe, Kota; Yokota, Shinpei; Matsuno, Rinta; Mikekado, Tsuyoshi; Yokoi, Hayato; Suzuki, Tohru

    2015-01-01

    The establishment of induced pluripotent stem (iPS) cell technology in fish could facilitate the establishment of novel cryopreservation techniques for storing selected aquaculture strains as frozen cells. In order to apply iPS cell technology to fish, we established a transgenic zebrafish line, Tg(Tru.oct4:EGFP), using green fluorescent protein (GFP) expression under the control of the oct4 gene promoter as a marker to evaluate multipotency in iPS cell preparations. We used the oct4 promoter from fugu (Takifugu rubripes) due to the compact nature of the fugu genome and to facilitate future applications of this technology in marine fishes. During embryogenesis, maternal GFP fluorescence was observed at the cleavage stage and zygotic GFP expression was observed from the start of the shield stage until approximately 24 h after fertilization. gfp messenger RNA (mRNA) was expressed by whole embryonic cells at the shield stage, and then restricted to the caudal neural tube in the latter stages of embryogenesis. These observations showed that GFP fluorescence and the regulation of gfp mRNA expression by the exogenous fugu oct4 promoter are well suited for monitoring endogenous oct4 mRNA expression in embryos. Bisulfite sequencing revealed that the rate of CpG methylation in the transgenic oct4 promoter was high in adult cells (98%) and low in embryonic cells (37%). These findings suggest that, as with the endogenous oct4 promoter, demethylation and methylation both take place normally in the transgenic oct4 promoter during embryogenesis. The embryonic cells harvested at the shield stage formed embryonic body-like cellular aggregates and maintained GFP fluorescence for 6 d when cultured on Transwell-COL Permeable Supports or a feeder layer of adult fin cells. Loss of GFP fluorescence by cultured cells was correlated with cellular differentiation. We consider that the Tg(Tru.oct4:EGFP) zebrafish line established here is well suited for monitoring multipotency in

  12. Molecular and electrophysiological characterization of GFP-expressing CA1 interneurons in GAD65-GFP mice.

    Directory of Open Access Journals (Sweden)

    Corette J Wierenga

    Full Text Available The use of transgenic mice in which subtypes of neurons are labeled with a fluorescent protein has greatly facilitated modern neuroscience research. GAD65-GFP mice, which have GABAergic interneurons labeled with GFP, are widely used in many research laboratories, although the properties of the labeled cells have not been studied in detail. Here we investigate these cells in the hippocampal area CA1 and show that they constitute ∼20% of interneurons in this area. The majority of them expresses either reelin (70±2% or vasoactive intestinal peptide (VIP; 15±2%, while expression of parvalbumin and somatostatin is virtually absent. This strongly suggests they originate from the caudal, and not the medial, ganglionic eminence. GFP-labeled interneurons can be subdivided according to the (partially overlapping expression of neuropeptide Y (42±3%, cholecystokinin (25±3%, calbindin (20±2% or calretinin (20±2%. Most of these subtypes (with the exception of calretinin-expressing interneurons target the dendrites of CA1 pyramidal cells. GFP-labeled interneurons mostly show delayed onset of firing around threshold, and regular firing with moderate frequency adaptation at more depolarized potentials.

  13. Transferring gfp gene with ion implantation and transient expression of gfp in liliaceous pollen cells

    Institute of Scientific and Technical Information of China (English)

    YUAN Shibin; CHEN Qizhong; WANG Yugang; ZHAO Weijiang; XU An; YANG Gen; WANG Wenxian; WU Lijun

    2004-01-01

    Liliaceous pollen cells were implanted by 4.0 MeV C2+ ion beam or by 25.0 keV N+ ion beam. Laser confocal scanning microscopy (LCSM) of the implanted intact samples showed that parts of the implanted pollen cells could be stained by propidium iodide (PI). This indicated that energetic ion beam could directly act on cells beneath the pollen coats and made channels for entry of the molecules from outside of the cells. LCSM analysis of green fluorescent protein (GFP) showed that energetic ion beam could mediate transient expression of gfp in treated pollen cells. Compared with 25.0 keV N+ ion beam, implantation of 4.0 MeV C2+ ion beam greatly improved gene transfer efficiency in pollen cells.

  14. Constructing retroviral vector carrying green fluorescent protein (GFP) and investigating the expression of GFP in primary rat myoblast

    Institute of Scientific and Technical Information of China (English)

    Shuling Rong; Yongxin Lu; Yuhua Liao; Xiaolin Wang; Xiaoqing Li; Jiahua Zhang; Yanli He

    2006-01-01

    Objective: To construct green fluorescent protein (GFP) retroviral vector (pLgXSN), and to investigate the expression of GFP in primary rat myoblast. Methods: GFP cDNA was subcloned into the plasmid pLgXSN, and the recombinant vector was transfected into packaging cell PT67. G418 was used to select positive colony. Myoblasts were infected by a high-titer viral supernatant. The recombinant retroviral plasmid vector was identified by restriction endonuclease analysis and DNA sequence analysis. Confocal microscopy and flow cytometry were used to detect the expression of GFP. Results: The GFP cDNA sequence was identical to that of GenBank. Recombinant retroviral plasmid vector pLgGFPSN was constructed successfully. The titer of the packaged recombinant retrovirus was 1 × 106 cfu/ml. Bright green fluorescence of the transfected cells was observed under confocal microscope 48 h after transfection. The transfection rate was 33%. The effective expression of GFP in myoblast infected by recombinant retrovirus lasted for 6 weeks. Conclusion: GFP gene could be effectively and stably expressed in myoblast, which suggests that GFP could act as a marker for studies on myoblast.

  15. Simultaneous tracking of fly movement and gene expression using GFP

    Directory of Open Access Journals (Sweden)

    Tavaré Simon

    2008-12-01

    Full Text Available Abstract Background Green Fluorescent Protein (GFP is used extensively as a reporter for transgene expression in Drosophila and other organisms. However, GFP has not generally been used as a reporter for circadian patterns of gene expression, and it has not previously been possible to correlate patterns of reporter expression with 3D movement and behavior of transgenic animals. Results We present a video tracking system that allows tissue-specific GFP expression to be quantified and correlated with 3D animal movement in real time. eyeless/Pax6 reporter expression had a 12 hr period that correlated with fly activity levels. hsp70 and hsp22 gene reporters were induced during fly aging in circadian patterns (24 hr and 18 hr periods, respectively, and spiked in the hours preceding and overlapping the death of the animal. The phase of hsp gene reporter expression relative to fly activity levels was different for each fly, and remained the same throughout the life span. Conclusion These experiments demonstrate that GFP can readily be used to assay longitudinally fly movement and tissue-specific patterns of gene expression. The hsp22-GFP and hsp70-GFP expression patterns were found to reflect accurately the endogenous gene expression patterns, including induction during aging and circadian periodicity. The combination of these new tracking methods with the hsp-GFP reporters revealed additional information, including a spike in hsp22 and hsp70 reporter expression preceding death, and an intriguing fly-to-fly variability in the phase of hsp70 and hsp22 reporter expression patterns. These methods allow specific temporal patterns of gene expression to be correlated with temporal patterns of animal activity, behavior and mortality.

  16. Fluorescent labeling of antibody fragments using split GFP.

    Directory of Open Access Journals (Sweden)

    Fortunato Ferrara

    Full Text Available Antibody fragments are easily isolated from in vitro selection systems, such as phage and yeast display. Lacking the Fc portion of the antibody, they are usually labeled using small peptide tags recognized by antibodies. In this paper we present an efficient method to fluorescently label single chain Fvs (scFvs using the split green fluorescent protein (GFP system. A 13 amino acid tag, derived from the last beta strand of GFP (termed GFP11, is fused to the C terminus of the scFv. This tag has been engineered to be non-perturbing, and we were able to show that it exerted no effect on scFv expression or functionality when compared to a scFv without the GFP11 tag. Effective functional fluorescent labeling is demonstrated in a number of different assays, including fluorescence linked immunosorbant assays, flow cytometry and yeast display. Furthermore, we were able to show that this split GFP system can be used to determine the concentration of scFv in crude samples, as well an estimate of antibody affinity, without the need for antibody purification. We anticipate this system will be of widespread interest in antibody engineering and in vitro display systems.

  17. Expression Analysis of CB2-GFP BAC Transgenic Mice.

    Science.gov (United States)

    Schmöle, Anne-Caroline; Lundt, Ramona; Gennequin, Benjamin; Schrage, Hanna; Beins, Eva; Krämer, Alexandra; Zimmer, Till; Limmer, Andreas; Zimmer, Andreas; Otte, David-Marian

    2015-01-01

    The endocannabinoid system (ECS) is a retrograde messenger system, consisting of lipid signaling molecules that bind to at least two G-protein-coupled receptors, Cannabinoid receptor 1 and 2 (CB1 and 2). As CB2 is primarily expressed on immune cells such as B cells, T cells, macrophages, dendritic cells, and microglia, it is of great interest how CB2 contributes to immune cell development and function in health and disease. Here, understanding the mechanisms of CB2 involvement in immune-cell function as well as the trafficking and regulation of CB2 expressing cells are crucial issues. Up to now, CB2 antibodies produce unclear results, especially those targeting the murine protein. Therefore, we have generated BAC transgenic GFP reporter mice (CB2-GFPTg) to trace CB2 expression in vitro and in situ. Those mice express GFP under the CB2 promoter and display GFP expression paralleling CB2 expression on the transcript level in spleen, thymus and brain tissue. Furthermore, by using fluorescence techniques we show that the major sources for GFP-CB2 expression are B cells in spleen and blood and microglia in the brain. This novel CB2-GFP transgenic reporter mouse line represents a powerful resource to study CB2 expression in different cell types. Furthermore, it could be used for analyzing CB2-mediated mobilization and trafficking of immune cells as well as studying the fate of recruited immune cells in models of acute and chronic inflammation.

  18. Expression Analysis of CB2-GFP BAC Transgenic Mice.

    Directory of Open Access Journals (Sweden)

    Anne-Caroline Schmöle

    Full Text Available The endocannabinoid system (ECS is a retrograde messenger system, consisting of lipid signaling molecules that bind to at least two G-protein-coupled receptors, Cannabinoid receptor 1 and 2 (CB1 and 2. As CB2 is primarily expressed on immune cells such as B cells, T cells, macrophages, dendritic cells, and microglia, it is of great interest how CB2 contributes to immune cell development and function in health and disease. Here, understanding the mechanisms of CB2 involvement in immune-cell function as well as the trafficking and regulation of CB2 expressing cells are crucial issues. Up to now, CB2 antibodies produce unclear results, especially those targeting the murine protein. Therefore, we have generated BAC transgenic GFP reporter mice (CB2-GFPTg to trace CB2 expression in vitro and in situ. Those mice express GFP under the CB2 promoter and display GFP expression paralleling CB2 expression on the transcript level in spleen, thymus and brain tissue. Furthermore, by using fluorescence techniques we show that the major sources for GFP-CB2 expression are B cells in spleen and blood and microglia in the brain. This novel CB2-GFP transgenic reporter mouse line represents a powerful resource to study CB2 expression in different cell types. Furthermore, it could be used for analyzing CB2-mediated mobilization and trafficking of immune cells as well as studying the fate of recruited immune cells in models of acute and chronic inflammation.

  19. Coherent Neutron Scattering and Collective Dynamics in the Protein, GFP

    Science.gov (United States)

    Nickels, Jonathan D.; Perticaroli, Stefania; O’Neill, Hugh; Zhang, Qiu; Ehlers, Georg; Sokolov, Alexei P.

    2013-01-01

    Collective dynamics are considered to be one of the major properties of soft materials, including biological macromolecules. We present coherent neutron scattering studies of the low-frequency vibrations, the so-called boson peak, in fully deuterated green fluorescent protein (GFP). Our analysis revealed unexpectedly low coherence of the atomic motions in GFP. This result implies a low amount of in-phase collective motion of the secondary structural units contributing to the boson peak vibrations and fast conformational fluctuations on the picosecond timescale. These observations are in contrast to earlier studies of polymers and glass-forming systems, and suggest that random or out-of-phase motions of the β-strands contribute greater than two-thirds of the intensity to the low-frequency vibrational spectra of GFP. PMID:24209864

  20. Visualization of C. elegans transgenic arrays by GFP

    Directory of Open Access Journals (Sweden)

    Sternberg Paul W

    2006-06-01

    Full Text Available Abstract Background Targeting the green fluorescent protein (GFP via the E. coli lac repressor (LacI to a specific DNA sequence, the lac operator (lacO, allows visualization of chromosomes in yeast and mammalian cells. In principle this method of visualization could be used for genetic mosaic analysis, which requires cell-autonomous markers that can be scored easily and at single cell resolution. The C. elegans lin-3 gene encodes an epidermal growth factor family (EGF growth factor. lin-3 is expressed in the gonadal anchor cell and acts through LET-23 (transmembrane protein tyrosine kinase and ortholog of EGF receptor to signal the vulval precursor cells to generate vulval tissue. lin-3 is expressed in the vulval cells later, and recent evidence raises the possibility that lin-3 acts in the vulval cells as a relay signal during vulval induction. It is thus of interest to test the site of action of lin-3 by mosaic analysis. Results We visualized transgenes in living C. elegans by targeting the green fluorescent protein (GFP via the E. coli lac repressor (LacI to a specific 256 sequence repeat of the lac operator (lacO incorporated into transgenes. We engineered animals to express a nuclear-localized GFP-LacI fusion protein. C. elegans cells having a lacO transgene result in nuclear-localized bright spots (i.e., GFP-LacI bound to lacO. Cells with diffuse nuclear fluorescence correspond to unbound nuclear localized GFP-LacI. We detected chromosomes in living animals by chromosomally integrating the array of the lacO repeat sequence and visualizing the integrated transgene with GFP-LacI. This detection system can be applied to determine polyploidy as well as investigating chromosome segregation. To assess the GFP-LacI•lacO system as a marker for mosaic analysis, we conducted genetic mosaic analysis of the epidermal growth factor lin-3, expressed in the anchor cell. We establish that lin-3 acts in the anchor cell to induce vulva development

  1. Evaluation of different promoters driving the GFP reporter gene in seaweed Kappaphycus alvarezii

    OpenAIRE

    Muh. Alias L. Rajamuddin; Alimuddin A; Utut Widyastuti; Irvan Faizal

    2016-01-01

    Promoter regulates expression level of foreign gene in transgenic organism. This study was performed to select asuitable promoter as the fi rst step towards production of valuable trait-enhanced seaweed by transgenic technology. Greenfl uorescent protein (GFP) gene was used as a reporter to determine the activity of promoter in seaweed Kappaphycusalvarezii. GFP gene constructs driven by cytomegalovirus (pCMV-GFP), caulifl ower mosaic virus (pCaMV-GFP),medaka β-actin (pmBA-GFP) and Japanese fl...

  2. Optimization of membrane protein overexpression and purification using GFP fusions

    NARCIS (Netherlands)

    Drew, David; Lerch, Mirjam; Kunji, Edmund; Slotboom, Dirk-Jan; de Gier, Jan-Willem

    2006-01-01

    Optimizing conditions for the overexpression and purification of membrane proteins for functional and structural studies is usually a Laborious and time-consuming process. This process can be accelerated using membrane protein-GFP fusions(1-3), which allows direct monitoring and visualization of mem

  3. Are "g" and the General Factor of Personality (GFP) Correlated?

    Science.gov (United States)

    Irwing, Paul; Booth, Tom; Nyborg, Helmuth; Rushton, J. Philippe

    2012-01-01

    We examined whether the General Factor of Personality (GFP) is related to the "g" factor of cognitive ability using data from the Vietnam Experience Study which randomly sampled 4462 Vietnam War veterans from a total sample of about five million Vietnam era army veterans. Exclusionary criteria included passing a fitness test, achieving a…

  4. Mapping eGFP oligomer mobility in living cell nuclei.

    Science.gov (United States)

    Dross, Nicolas; Spriet, Corentin; Zwerger, Monika; Müller, Gabriele; Waldeck, Waldemar; Langowski, Jörg

    2009-01-01

    Movement of particles in cell nuclei can be affected by viscosity, directed flows, active transport, or the presence of obstacles such as the chromatin network. Here we investigate whether the mobility of small fluorescent proteins is affected by the chromatin density. Diffusion of inert fluorescent proteins was studied in living cell nuclei using fluorescence correlation spectroscopy (FCS) with a two-color confocal scanning detection system. We first present experiments exposing FCS-specific artifacts encountered in live cell studies as well as strategies to prevent them, in particular those arising from the choice of the fluorophore used for calibration of the focal volume, as well as temperature and acquisition conditions used for fluorescence fluctuation measurements. After defining the best acquisition conditions, we show for various human cell lines that the mobility of GFP varies significantly within the cell nucleus, but does not correlate with chromatin density. The intranuclear diffusional mobility strongly depends on protein size: in a series of GFP-oligomers, used as free inert fluorescent tracers, the diffusion coefficient decreased from the monomer to the tetramer much more than expected for molecules free in aqueous solution. Still, the entire intranuclear chromatin network is freely accessible for small proteins up to the size of eGFP-tetramers, regardless of the chromatin density or cell line. Even the densest chromatin regions do not exclude free eGFP-monomers or multimers.

  5. Mapping eGFP oligomer mobility in living cell nuclei.

    Directory of Open Access Journals (Sweden)

    Nicolas Dross

    Full Text Available Movement of particles in cell nuclei can be affected by viscosity, directed flows, active transport, or the presence of obstacles such as the chromatin network. Here we investigate whether the mobility of small fluorescent proteins is affected by the chromatin density. Diffusion of inert fluorescent proteins was studied in living cell nuclei using fluorescence correlation spectroscopy (FCS with a two-color confocal scanning detection system. We first present experiments exposing FCS-specific artifacts encountered in live cell studies as well as strategies to prevent them, in particular those arising from the choice of the fluorophore used for calibration of the focal volume, as well as temperature and acquisition conditions used for fluorescence fluctuation measurements. After defining the best acquisition conditions, we show for various human cell lines that the mobility of GFP varies significantly within the cell nucleus, but does not correlate with chromatin density. The intranuclear diffusional mobility strongly depends on protein size: in a series of GFP-oligomers, used as free inert fluorescent tracers, the diffusion coefficient decreased from the monomer to the tetramer much more than expected for molecules free in aqueous solution. Still, the entire intranuclear chromatin network is freely accessible for small proteins up to the size of eGFP-tetramers, regardless of the chromatin density or cell line. Even the densest chromatin regions do not exclude free eGFP-monomers or multimers.

  6. Cellular GFP Toxicity and Immunogenicity: Potential Confounders in in Vivo Cell Tracking Experiments.

    Science.gov (United States)

    Ansari, Amir Mehdi; Ahmed, A Karim; Matsangos, Aerielle E; Lay, Frank; Born, Louis J; Marti, Guy; Harmon, John W; Sun, Zhaoli

    2016-10-01

    Green Fluorescent protein (GFP), used as a cellular tag, provides researchers with a valuable method of measuring gene expression and cell tracking. However, there is evidence to suggest that the immunogenicity and cytotoxicity of GFP potentially confounds the interpretation of in vivo experimental data. Studies have shown that GFP expression can deteriorate over time as GFP tagged cells are prone to death. Therefore, the cells that were originally marked with GFP do not survive and cannot be accurately traced over time. This review will present current evidence for the immunogenicity and cytotoxicity of GFP in in vivo studies by characterizing these responses.

  7. Welfare assessment in transgenic pigs expressing green fluorescent protein (GFP)

    DEFF Research Database (Denmark)

    Huber, Reinhard C.; Remuge, Liliana; Carlisle, Ailsa

    2012-01-01

    Since large animal transgenesis has been successfully attempted for the first time about 25 years ago, the technology has been applied in various lines of transgenic pigs. Nevertheless one of the concerns with the technology—animal welfare—has not been approached through systematic assessment...... and statements regarding the welfare of transgenic pigs have been based on anecdotal observations during early stages of transgenic programs. The main aim of the present study was therefore to perform an extensive welfare assessment comparing heterozygous transgenic animals expressing GFP with wildtype animals...... months. The absence of significant differences between GFP and wildtype animals in the parameters observed suggests that the transgenic animals in question are unlikely to suffer from deleterious effects of transgene expression on their welfare and thus support existing anecdotal observations of pigs...

  8. Bioreporters: gfp versus lux revisited and single-cell response.

    Science.gov (United States)

    Kohlmeier, Stefanie; Mancuso, Matthew; Tecon, Robin; Harms, Hauke; van der Meer, Jan Roelof; Wells, Mona

    2007-03-15

    Genetically engineered organisms expressing spectroscopically active reporter molecules in response to chemical effectors display great potential as living transducers in sensing applications. Green fluorescent protein (gfp gene) bioreporters have distinct advantages over luminescent couterparts (lux gene), including applicability at the single-cell level, but are typically less sensitive. Here we describe a gfp-bearing bioreporter that is sensitive to naphthalene (a poorly water soluble pollutant behaving like a large class of hydrophobic compounds), is suitable for use in chemical assays and bioavailability studies, and has detection limits comparable to lux-bearing bioreporters for higher efficiency detection strategies. Simultaneously, we find that the exploitation of population response data from single-cell analysis is not an algorithmic conduit to enhanced signal detection and hence lower effector detection limits, as normally assumed. The assay reported functions to equal effect with or without biocide.

  9. Visualization of C. elegans transgenic arrays by GFP

    OpenAIRE

    Sternberg Paul W; Gonzalez-Serricchio Aidyl S

    2006-01-01

    Abstract Background Targeting the green fluorescent protein (GFP) via the E. coli lac repressor (LacI) to a specific DNA sequence, the lac operator (lacO), allows visualization of chromosomes in yeast and mammalian cells. In principle this method of visualization could be used for genetic mosaic analysis, which requires cell-autonomous markers that can be scored easily and at single cell resolution. The C. elegans lin-3 gene encodes an epidermal growth factor family (EGF) growth factor. lin-3...

  10. hNIS-IRES-eGFP Dual Reporter Gene Imaging

    Directory of Open Access Journals (Sweden)

    Jiantu Che

    2005-04-01

    Full Text Available The human and rodent sodium iodide symporters (NIS have recently been cloned and are being investigated as potential therapeutic and reporter genes. We have extended this effort by constructing an internal ribosomal entry site (IRES-linked human NIS (hNIS-enhanced green fluorescent protein (eGFP hybrid reporter gene for both nuclear and optical imaging. A self-inactivating retroviral vector, termed pQCNIG, containing hNIS-IRES-eGFP dual reporter gene, driven by a constitutive CMV promoter, was constructed and used to generate RG2-pQCNIG cells and RG2-pQCNIG tumors. 131I-iodide and 99mTcO4-pertechnetate accumulation studies plus fluorescence microscopy and intensity assays were performed in vitro, and gamma camera imaging studies in RG2-pQCNIG and RG2 tumor-bearing athymic rats were performed. RG2-pQCNIG cells expressed high levels of hNIS protein and showed high intensity of eGFP fluorescence compared with RG2 wild-type cells. RG2-pQCNIG cells accumulated Na131I and 99mTcO4– to a 50:1 and a 170:1 tissue/medium ratio at 10 min, compared with 0.8:1.2 tissue/medium ratio in wild-type RG2 cells. A significant correlation between radiotracer accumulation and eGFP fluorescence intensity was demonstrated. RG2-pQCNIG and RG2 tumors were readily differentiated by in vivo gamma camera imaging; radiotracer uptake increased in RG2-pQCNIG but declined in RG2 tumors over the 50-min imaging period. Stomach and thyroid were the major organs of radionuclide accumulation. The IRES-linked hNIS-eGFP dual reporter gene is functional and stable in transduced RG2-pQCNIG cells. Optical and nuclear imaging of tumors produced from these cell lines provides the opportunity to monitor tumor growth and response to therapy. These studies indicate the potential for a wider application of hNIS reporter imaging and translation into patient studies using radioisotopes that are currently available for human use for both SPECT and PET imaging.

  11. File list: Oth.Pup.05.GFP.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  12. File list: Oth.Epd.50.GFP.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  13. File list: Oth.Epd.05.GFP.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  14. File list: Oth.ALL.20.GFP.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  15. File list: Oth.Oth.05.GFP.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  17. File list: Oth.Adl.50.GFP.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  18. File list: Oth.ALL.50.GFP.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

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    Lifescience Database Archive (English)

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    Lifescience Database Archive (English)

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  1. File list: Oth.Neu.20.GFP.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  2. File list: Oth.ALL.20.GFP.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  3. File list: Oth.ALL.05.GFP.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  4. File list: Oth.Lar.20.GFP.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.Lar.20.GFP.AllCell ce10 TFs and others GFP Larvae SRX080088,SRX080082,SRX080078...5098,SRX015093 http://dbarchive.biosciencedbc.jp/kyushu-u/ce10/assembled/Oth.Lar.20.GFP.AllCell.bed ...

  5. File list: Oth.Adl.20.GFP.AllCell [Chip-atlas[Archive

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  6. File list: Oth.Adl.10.GFP.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  7. File list: Oth.Utr.10.GFP.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  8. File list: Oth.Kid.10.GFP.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  9. File list: Oth.Liv.05.GFP.AllCell [Chip-atlas[Archive

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  10. File list: Oth.Pan.10.GFP.AllCell [Chip-atlas[Archive

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  11. File list: Oth.Emb.05.GFP.AllCell [Chip-atlas[Archive

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  14. File list: Oth.Emb.05.GFP.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  15. File list: Oth.Emb.20.GFP.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  16. File list: Oth.Pup.50.GFP.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  17. File list: Oth.Pup.10.GFP.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  18. File list: Oth.Pup.20.GFP.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  19. Encapsulation of GFP in Complex Coacervate Core Micelles.

    Science.gov (United States)

    Nolles, Antsje; Westphal, Adrie H; de Hoop, Jacob A; Fokkink, Remco G; Kleijn, J Mieke; van Berkel, Willem J H; Borst, Jan Willem

    2015-05-11

    Protein encapsulation with polymers has a high potential for drug delivery, enzyme protection and stabilization. Formation of such structures can be achieved by the use of polyelectrolytes to generate so-called complex coacervate core micelles (C3Ms). Here, encapsulation of enhanced green fluorescent protein (EGFP) was investigated using a cationic-neutral diblock copolymer of two different sizes: poly(2-methyl-vinyl-pyridinium)41-b-poly(ethylene-oxide)205 and poly(2-methyl-vinyl-pyridinium)128-b-poly(ethylene-oxide)477. Dynamic light scattering and fluorescence correlation spectroscopy (FCS) revealed a preferred micellar composition (PMC) with a positive charge composition of 0.65 for both diblock copolymers and micellar hydrodynamic radii of approximately 34 nm. FCS data show that at the PMC, C3Ms are formed above 100 nM EGFP, independent of polymer length. Mixtures of EGFP and nonfluorescent GFP were used to quantify the amount of GFP molecules per C3M, resulting in approximately 450 GFPs encapsulated per micelle. This study shows that FCS can be successfully applied for the characterization of protein-containing C3Ms.

  20. Use of the Nanofitin Alternative Scaffold as a GFP-Ready Fusion Tag.

    Directory of Open Access Journals (Sweden)

    Simon Huet

    Full Text Available With the continuous diversification of recombinant DNA technologies, the possibilities for new tailor-made protein engineering have extended on an on-going basis. Among these strategies, the use of the green fluorescent protein (GFP as a fusion domain has been widely adopted for cellular imaging and protein localization. Following the lead of the direct head-to-tail fusion of GFP, we proposed to provide additional features to recombinant proteins by genetic fusion of artificially derived binders. Thus, we reported a GFP-ready fusion tag consisting of a small and robust fusion-friendly anti-GFP Nanofitin binding domain as a proof-of-concept. While limiting steric effects on the carrier, the GFP-ready tag allows the capture of GFP or its blue (BFP, cyan (CFP and yellow (YFP alternatives. Here, we described the generation of the GFP-ready tag from the selection of a Nanofitin variant binding to the GFP and its spectral variants with a nanomolar affinity, while displaying a remarkable folding stability, as demonstrated by its full resistance upon thermal sterilization process or the full chemical synthesis of Nanofitins. To illustrate the potential of the Nanofitin-based tag as a fusion partner, we compared the expression level in Escherichia coli and activity profile of recombinant human tumor necrosis factor alpha (TNFα constructs, fused to a SUMO or GFP-ready tag. Very similar expression levels were found with the two fusion technologies. Both domains of the GFP-ready tagged TNFα were proved fully active in ELISA and interferometry binding assays, allowing the simultaneous capture by an anti-TNFα antibody and binding to the GFP, and its spectral mutants. The GFP-ready tag was also shown inert in a L929 cell based assay, demonstrating the potent TNFα mediated apoptosis induction by the GFP-ready tagged TNFα. Eventually, we proposed the GFP-ready tag as a versatile capture and labeling system in addition to expected applications of anti-GFP

  1. Construction of the Recombinant Expression Plasmid pB1121-GFP-62390 and pB1121-GFP-51780 Contained Green Fluorescent Protein Gene%含绿色荧光蛋白(gfp)基因的植物重组表达载体pBI121-GFP-62390和pBI121-GFP-51780的构建

    Institute of Scientific and Technical Information of China (English)

    邓丽; 刘红; 杨万年

    2008-01-01

    [目的]构建含绿色荧光蛋白(gfp)基因的植物重组表达载体pB1121-GFP-62390和pB1121-GFP-51780.[方法]用PCR方法扩增psmGFP的GFP片段,BamH I和Sacl双酶切PCR产物,同时用BarnH I和SacI双酶切pB1121.从琼脂糖凝胶中回收纯化pB1121的大片段,经连接、转化、鉴定出改造后的质粒.[结果]用PCR方法扩增得到长度为740 bp的增强型的绿色荧光蛋白基因片段,克隆入pB1121表达载体后,获得了新的重组质粒pB1121-GFP.分别将编码拟南芥BAG7、BACA蛋白的基因At5g62390和At3g51780通过PCR方法扩增后,克隆入pB1121-GFP,构建了用于超量表达BAG蛋白基因的GFP融合蛋白双元表达载体pB1121-GFP-62390和pB1121-GFP-51780.利用细胞感受态法将该植物表达载体分别导入根癌农杆菌GV3101中.[结论]为进一步研究BAG蛋白在拟南芥抗性胁迫中的功能及其在细胞内的动态分布奠定了基础.

  2. Live imaging of GFP-labeled proteins in Drosophila oocytes.

    Science.gov (United States)

    Pokrywka, Nancy Jo

    2013-03-29

    The Drosophila oocyte has been established as a versatile system for investigating fundamental questions such as cytoskeletal function, cell organization, and organelle structure and function. The availability of various GFP-tagged proteins means that many cellular processes can be monitored in living cells over the course of minutes or hours, and using this technique, processes such as RNP transport, epithelial morphogenesis, and tissue remodeling have been described in great detail in Drosophila oocytes. The ability to perform video imaging combined with a rich repertoire of mutants allows an enormous variety of genes and processes to be examined in incredible detail. One such example is the process of ooplasmic streaming, which initiates at mid-oogenesis. This vigorous movement of cytoplasmic vesicles is microtubule and kinesin-dependent and provides a useful system for investigating cytoskeleton function at these stages. Here I present a protocol for time lapse imaging of living oocytes using virtually any confocal microscopy setup.

  3. Development of Neutralization Assay Using an eGFP Chikungunya Virus

    Directory of Open Access Journals (Sweden)

    Cheng-Lin Deng

    2016-06-01

    Full Text Available Chikungunya virus (CHIKV, a member of the Alphavirus genus, is an important human emerging/re-emerging pathogen. Currently, there are no effective antiviral drugs or vaccines against CHIKV infection. Herein, we construct an infectious clone of CHIKV and an eGFP reporter CHIKV (eGFP-CHIKV with an isolated strain (assigned to Asian lineage from CHIKV-infected patients. The eGFP-CHIKV reporter virus allows for direct visualization of viral replication through the levels of eGFP expression. Using a known CHIKV inhibitor, ribavirin, we confirmed that the eGFP-CHIKV reporter virus could be used to identify inhibitors against CHIKV. Importantly, we developed a novel and reliable eGFP-CHIKV reporter virus-based neutralization assay that could be used for rapid screening neutralizing antibodies against CHIKV.

  4. Dose-dependent Toxicity of Humanized Renilla reniformis GFP (hrGFP Limits Its Utility as a Reporter Gene in Mouse Muscle

    Directory of Open Access Journals (Sweden)

    Lindsay M Wallace

    2013-01-01

    Full Text Available Gene therapy has historically focused on delivering protein-coding genes to target cells or tissues using a variety of vectors. In recent years, the field has expanded to include gene-silencing strategies involving delivery of noncoding inhibitory RNAs, such as short hairpin RNAs or microRNAs (miRNAs. Often called RNA interference (RNAi triggers, these small inhibitory RNAs are difficult or impossible to visualize in living cells or tissues. To circumvent this detection problem and ensure efficient delivery in preclinical studies, vectors can be engineered to coexpress a fluorescent reporter gene to serve as a marker of transduction. In this study, we set out to optimize adeno-associated viral (AAV vectors capable of delivering engineered miRNAs and green fluorescent protein (GFP reporter genes to skeletal muscle. Although the more broadly utilized enhanced GFP (eGFP gene derived from the jellyfish, Aequorea victoria was a conventional choice, we were concerned about some previous studies suggesting this protein was myotoxic. We thus opted to test vectors carrying the humanized Renilla reniformis-derived GFP (hrGFP gene, which has not seen as extensive usage as eGFP but was purported to be a safer and less cytotoxic alternative. Employing AAV6 vector dosages typically used in preclinical gene transfer studies (3×1010 –1 × 1011 particles, we found that hrGFP caused dose-dependent myopathy when delivered to wild-type (wt mouse muscle, whereas identical titers of AAV6 carrying eGFP were relatively benign. Dose de-escalation at or below 8 × 109 AAV particles effectively reduced or eliminated hrGFP-associated myotoxicity, but also had dampening effects on green fluorescence and miRNA-mediated gene silencing in whole muscles. We conclude that hrGFP is impractical for use as a transduction marker in preclinical, AAV-based RNA interference therapy studies where adult mouse muscle is the target organ. Moreover, our data support that eGFP is superior

  5. Creation of Mice Bearing a Partial Duplication of HPRT Gene Marked with a GFP Gene and Detection of Revertant Cells In Situ as GFP-Positive Somatic Cells.

    Directory of Open Access Journals (Sweden)

    Asao Noda

    Full Text Available It is becoming clear that apparently normal somatic cells accumulate mutations. Such accumulations or propagations of mutant cells are thought to be related to certain diseases such as cancer. To better understand the nature of somatic mutations, we developed a mouse model that enables in vivo detection of rare genetically altered cells via GFP positive cells. The mouse model carries a partial duplication of 3' portion of X-chromosomal HPRT gene and a GFP gene at the end of the last exon. In addition, although HPRT gene expression was thought ubiquitous, the expression level was found insufficient in vivo to make the revertant cells detectable by GFP positivity. To overcome the problem, we replaced the natural HPRT-gene promoter with a CAG promoter. In such animals, termed HPRT-dup-GFP mouse, losing one duplicated segment by crossover between the two sister chromatids or within a single molecule of DNA reactivates gene function, producing hybrid HPRT-GFP proteins which, in turn, cause the revertant cells to be detected as GFP-positive cells in various tissues. Frequencies of green mutant cells were measured using fixed and frozen sections (liver and pancreas, fixed whole mount (small intestine, or by means of flow cytometry (unfixed splenocytes. The results showed that the frequencies varied extensively among individuals as well as among tissues. X-ray exposure (3 Gy increased the frequency moderately (~2 times in the liver and small intestine. Further, in two animals out of 278 examined, some solid tissues showed too many GFP-positive cells to score (termed extreme jackpot mutation. Present results illustrated a complex nature of somatic mutations occurring in vivo. While the HPRT-dup-GFP mouse may have a potential for detecting tissue-specific environmental mutagens, large inter-individual variations of mutant cell frequency cause the results unstable and hence have to be reduced. This future challenge will likely involve lowering the

  6. Evaluation of different promoters driving the GFP reporter gene in seaweed Kappaphycus alvarezii

    Directory of Open Access Journals (Sweden)

    Muh. Alias L. Rajamuddin

    2016-02-01

    Full Text Available Promoter regulates expression level of foreign gene in transgenic organism. This study was performed to select asuitable promoter as the fi rst step towards production of valuable trait-enhanced seaweed by transgenic technology. Greenfl uorescent protein (GFP gene was used as a reporter to determine the activity of promoter in seaweed Kappaphycusalvarezii. GFP gene constructs driven by cytomegalovirus (pCMV-GFP, caulifl ower mosaic virus (pCaMV-GFP,medaka β-actin (pmBA-GFP and Japanese fl ounder keratin (pJfKer-GFP promoters were introduced by electroporationmethod. Electroporation was performed using a gene pulser (BIORAD with voltage of 300 V, pulse length of 0.5 ms,pulse numbers of 4, and pulse interval of 0.1 s. Promoter activity was determined by analyzing GFP gene expressionlevel using a fl uorescent microscope. The results showed that CMV regulated highest number of fi lament callus(34.10%±1.49 expressing GFP at medium to strong fl uorescence levels. CaMV promoter had relatively similar activitywith CMV, but lower number of fi lament callus expressing GFP (10.48%±0.25. mBA promoter drove GFP expressionat medium level and similar number of fi lament callus (8.85%±2.31 expressing GFP with CaMV, while JfKer promoterhad lowest activity by means in number of fi lament callus expressing GFP (4.79%±0.26 and GFP expression level. PCRanalysis for transgenic confi rmation showed a DNA band of PCR product from pCMV-GFP and pCaMV-GFP expressingfi lament callus in the same size (about 0.6 kb with positive control of plasmid. Thus, CMV and CaMV promoters wasan appropriate promoter and foreign gene could be transferred to fi lament callus by electroporation method. Combiningthis achievement with developing a culture method of fi lament callus to be thallus, stable transgenic breeding in K.alvarezii can be feasible.

  7. Expression of GFP in nuclear transplants generated by transplantation of embryonic cell nuclei from GFP-transgenic fish into nonenucleated eggs of medaka, Oryzias latipes.

    Science.gov (United States)

    Niwa, K; Kani, S; Kinoshita, M; Ozato, K; Wakamatsu, Y

    2000-01-01

    In order to investigate whether foreign genes can be used as genetic markers of donor nuclei in fish nuclear transplantation, expression of the GFP gene derived from donor nuclei was examined in nuclear transplants in medaka (Oryzias latipes). Embryonic nuclei were obtained from blastula embryos produced by crossing of transgenic fish of the wild-type strain heterozygous for the GFP gene with nontransgenic ones or by mutual crossing between transgenic fish. The GFP gene was driven by the promoter of the medaka elongation factor gene, EF-1alpha-A, which is known to induce GFP expression in many tissues except for the muscle in the transgenic fish. The nuclei were transplanted into nonenucleated unfertilized eggs of the orange-red strain. Adult nuclear transplants were successfully obtained at the rate of about 2% of the operated eggs. They were triploid and had no reproductive potential. The GFP gene was expressed in embryos, fry, and adults of nuclear transplants in a pattern similar to that in the transgenic fish. These results indicate that GFP is useful as a foreign genetic marker of donor nuclei in fish nuclear transplantation.

  8. Generalization of Boolean Functions Properties to Functions Defined over GF(p

    Directory of Open Access Journals (Sweden)

    Saad Elmansori

    2012-01-01

    Full Text Available Problem statement: Traditionally, cryptographic applications designed on hardware have always tried to take advantage of the simplicity of implementation functions over GF(p, p = 2, to reduce costs and improve performance. On the contrast, functions defined over GF(p; p > 2, possess far better cryptographic properties than GF(2 functions. Approach: We generalize some of the previous results on cryptographic Boolean functions to functions defined over GF(p; p > 2. Results: We generalize Siegenthaler’s construction to functions defined over finite field. We characterize the linear structures of functions over GF(p in terms of their Walsh transform values. We then investigate the relation between the autocorrelation coefficients of functions over GF(p and their Walsh spectrum. We also derive an upper bound for the dimension of the linear space of the functions defined over GF(p. Finally, we present a method to construct a bent function from semi-bent functions. Conclusion: Functions defined over GF(p can achieve better cryptographic bounds than GF(2 functions. In this paper we gave a generalization of several of the GF(2 cryptographic properties to functions defined over GF(p, where p is an odd prime.

  9. Integration and Expression of gfp in the plastid of Medicago sativa L.

    Science.gov (United States)

    Xing, Shaochen; Wei, Zhengyi; Wang, Yunpeng; Liu, Yanzhi; Lin, Chunjing

    2014-01-01

    Here we describe a protocol of alfalfa (Medicago sativa L.) plastid transformation by which gfp, a gene encoding the green fluorescent protein (GFP), is inserted into plastid genome via particle bombardment and homoplastomic plant is obtained. Plastid engineering is likely to make a significant contribution to the genetic improvement of this crop and the production of vaccines and therapeutic proteins.

  10. Green fluorescent protein (GFP) transgenic pig produced by somatic cell nuclear transfer

    Institute of Scientific and Technical Information of China (English)

    LIU ZhongHua; SUN Shuang; LI YuTian; WANG HongBin; R S PRATHER; SONG Jun; WANG ZhenKun; TIAN JiangTian; KONG QingRan; ZHENG Zhong; YIN Zhi; GAO Li; MA HaiKun

    2008-01-01

    Transgenic somatic cell nuclear transfer is a very promising route for producing transgenic farm ani-mals. Research on GFP transgenic pigs can provide useful information for breeding transgenic pigs, human disease models and human organ xenotransplantation. In this study, a liposomal transfection system was screened and transgenic embryos were reconstructed by nuclear transfer of GFP positive cells into enucleated in vitro matured oocytes. The development of reconstructed embryos both in vitro and in vivo was observed, and GFP expression was determined. The results showed that porcine fe-tal-derived fibroblast cells cultured with 4.0 plJmL liposome and 1.6 pg/mL plasmid DNA for 6 h re-sulted in the highest transfection rate (3.6%). The percentage of GFP reconstructed embryos that de-veloped in vitro to the blastocyst stage was 10%. Of those the GFP positive percentage was 48%. Re-constructed transgenic embryos were transferred to 10 recipients. 5 of them were pregnant, and 3 de-livered 6 cloned piglets in which 4 piglets were transgenic for the GFP as verified by both GFP protein expression and GFP DNA sequence analysis. The percentage of reconstructed embryos that resulted in cloned piglets was 1.0%; while the percentage of piglets that were transgenic was 0.7%. This is the first group of transgenic cloned pigs born in China, marking a great progress in Chinese transgenic cloned pig research.

  11. The General Factor of Personality (GFP) and parental support: Testing a prediction from Life History Theory

    NARCIS (Netherlands)

    Linden, D. van der; Figueredo, A.J.; Leeuw, R.N.H. de; Scholte, R.H.J.; Engels, R.C.M.E.

    2012-01-01

    In the present study, we tested whether the General Factor of Personality (GFP) is related to the level of parental support. The GFP is assumed to occupy the apex of the hierarchy of human personality structure and is believed to reflect a socially and sexually selected aggregate of behavioral chara

  12. Isolation of progenitor cells from GFP-transgenic pigs and transplantation to the retina of allorecipients

    DEFF Research Database (Denmark)

    Klassen, Henry; Warfvinge, Karin; Schwartz, Philip H

    2008-01-01

    to survival as allografts and integrate into the host retinal architecture, we isolated donor cells from fetal green fluorescent protein (GFP)-transgenic pigs. Cultures were propagated from the brain, retina, and corneo-scleral limbus. GFP expression rapidly increased with time in culture, although lower......Work in rodents has demonstrated that progenitor transplantation can achieve limited photoreceptor replacement in the mammalian retina; however, replication of these findings on a clinically relevant scale requires a large animal model. To evaluate the ability of porcine retinal progenitor cells...... in conjunction with photoreceptor markers and glial fibrillary acid protein (GFAP), thus suggesting downregulation of GFP during differentiation. Following transplantation, GFP expression allowed histological visualization of integrated cells and extension of fine processes to adjacent plexiform layers. GFP...

  13. Expression characteristics of GFP driven by NAC1 promoter and its responses to auxin and gibberellin

    Institute of Scientific and Technical Information of China (English)

    WANG Youhua; DUAN Liusheng; LU Mengzhu; LI Zhaohu; WANG Minjie; ZHAI Zhixi

    2006-01-01

    A 1050 bp fragment upstream transcription start site of a transcription factor gene NAC1 in Arabidopsis thaliana was amplified and cloned into plasmid pRD420 to construct a green fluorescent protein(GFP) fusion system under the control of NAC1 promoter. Plasmids were introduced into tobacco by Agrobacterium mediated method to regenerate plants with NAC1-GFP gene, and expression pattern of NAC1-GFP and its responses to auxin and gibberellin (GA) were observed. GFP was found to accumulate specifically in root, and was detected after treatment of auxin, N-1-Naphthylphthalamic acid (NPA, an auxin antagonist) or GA3. It was indicated that the expression of GFP driven by NAC1 promoter was induced not only by auxin but also by GAs, suggesting that NAC1 mediated both the auxin signaling and the GAs signaling involved in lateral roots development.

  14. Prokaryotic expression and characterization of a pea actin isoform (PEAcl) fused to GFP

    Institute of Scientific and Technical Information of China (English)

    ZHANG Shaobin; REN Dongtao; XU Xiaojing; LIU Guoqin

    2004-01-01

    Actins widely exist in eukaryotic cells and play important roles in many living activities. As there are many kinds of actin isoforms in plant cells, it is difficult to purify each actin isoform in sufficient quantities for analyzing its physicochemical properties. In the present study, a pea(Pisum Sativum L.) actin isoform (PEAc1) fused to His-tag at its amino terminus and GFP (green fluorescent protein) at its Carboxyl terminus were expressed in E. Coli in inclusion bodies. The fusion protein (PEAc1-GFP) was highly purified with the yield of above 2 mg/L culture by dissolving inclusions in 8 mol/L urea, renaturing by dialysis in a gradient of urea, and affinity binding to Ni-resin. The purified mono meric PEAc1-GFP could efficiently bind on Dnase Ⅰ and inhibit the latter's enzyme activity. PEAc1-GFP could polymerize into green fluorescent filamentous structures (F-PEAc1-GFP), which could be labeled by TRITC-phalloidin, a specific agent for observing microfilaments. The PEAc1-GFP polymerization curve was identical with that of chicken skeletal muscle actin. The critical concentration for PEAc1-GFP to polymerize into filaments is 0.24 μmol/L. The F-PEAc1-GFP could stimulate myosin Mg-ATPase activity in a protein concentration dependant manner (about 4 folds at1 mg/mL F-PEAc1-GFP). The results above show that the PEAcl fused to GFP retained the assembly characteristic of actin, indicating that gene fusion, prokaryotic expression,denaturation and renaturation, and affinity chromatography is a useful strategy for obtaining plant actin isoform proteins in a large amount.

  15. Non-Target Effects of Green Fluorescent Protein (GFP-Derived Double-Stranded RNA (dsRNA-GFP Used in Honey Bee RNA Interference (RNAi Assays

    Directory of Open Access Journals (Sweden)

    Francis M. F. Nunes

    2013-01-01

    Full Text Available RNA interference has been frequently applied to modulate gene function in organisms where the production and maintenance of mutants is challenging, as in our model of study, the honey bee, Apis mellifera. A green fluorescent protein (GFP-derived double-stranded RNA (dsRNA-GFP is currently commonly used as control in honey bee RNAi experiments, since its gene does not exist in the A. mellifera genome. Although dsRNA-GFP is not expected to trigger RNAi responses in treated bees, undesirable effects on gene expression, pigmentation or developmental timing are often observed. Here, we performed three independent experiments using microarrays to examine the effect of dsRNA-GFP treatment (introduced by feeding on global gene expression patterns in developing worker bees. Our data revealed that the expression of nearly 1,400 genes was altered in response to dsRNA-GFP, representing around 10% of known honey bee genes. Expression changes appear to be the result of both direct off-target effects and indirect downstream secondary effects; indeed, there were several instances of sequence similarity between putative siRNAs generated from the dsRNA-GFP construct and genes whose expression levels were altered. In general, the affected genes are involved in important developmental and metabolic processes associated with RNA processing and transport, hormone metabolism, immunity, response to external stimulus and to stress. These results suggest that multiple dsRNA controls should be employed in RNAi studies in honey bees. Furthermore, any RNAi studies involving these genes affected by dsRNA-GFP in our studies should use a different dsRNA control.

  16. Properties of GluR3 receptors tagged with GFP at the amino or carboxyl terminus

    Science.gov (United States)

    Limon, Agenor; Reyes-Ruiz, Jorge Mauricio; Eusebi, Fabrizio; Miledi, Ricardo

    2007-01-01

    Anatomical visualization of neurotransmitter receptor localization is facilitated by tagging receptors, but this process can alter their functional properties. We have evaluated the distribution and properties of WT glutamate receptor 3 (GluR3) α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) receptors (WT GluR3) and two receptors in which GFP was tagged to the amino terminus (GFP-GluR3) or to the carboxyl terminus (GluR3-GFP). Although the fluorescence in Xenopus oocytes was stronger in the vegetal hemisphere because of localization of internal structures (probable sites of production, storage or recycling of receptors), the insertion of receptors into the plasma membrane was polarized to the animal hemisphere. The fluorescence intensity of oocytes injected with GluR3-GFP RNA was approximately double that of oocytes injected with GFP-GluR3 RNA. Accordingly, GluR3-GFP oocytes generated larger kainate-induced currents than GFP-GluR3 oocytes, with similar EC50 values. Currents elicited by glutamate, or AMPA coapplied with cyclothiazide, were also larger in GluR3-GFP oocytes. The glutamate- to kainate-current amplitude ratios differed, with GluR3-GFP being activated more efficiently by glutamate than the WT or GFP-GluR3 receptors. This pattern correlates with the slower decay of glutamate-induced currents generated by GluR3-GFP receptors. These changes were not observed when GFP was tagged to the amino terminus, and these receptors behaved like the WT. The antagonistic effects of 6-nitro-7-sulfamoylbenzo[f]quinoxaline-2,3-dione (NBQX) and 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX) were not altered in any of the tagged receptors. We conclude that GFP is a useful and convenient tag for visualizing these proteins. However, the effects of different sites of tag insertion on receptor characteristics must be taken into account in assessing the roles played by these receptor proteins. PMID:17881566

  17. Plasmids for C-terminal tagging in Saccharomyces cerevisiae that contain improved GFP proteins, Envy and Ivy.

    Science.gov (United States)

    Slubowski, Christian J; Funk, Alyssa D; Roesner, Joseph M; Paulissen, Scott M; Huang, Linda S

    2015-04-01

    Green fluorescent protein (GFP) has become an invaluable tool in biological research. Many GFP variants have been created that differ in brightness, photostability, and folding robustness. We have created two hybrid GFP variants, Envy and Ivy, which we placed in a vector for the C-terminal tagging of yeast proteins by PCR-mediated recombination. The Envy GFP variant combines mutations found in the robustly folding SuperfolderGFP and GFPγ, while the Ivy GFP variant is a hybrid of GFPγ and the yellow-green GFP variant, Clover. We compared Envy and Ivy to EGFP, SuperfolderGFP and GFPγ and found that Envy is brighter than the other GFP variants at both 30°C and 37°C, while Ivy is the most photostable. Envy and Ivy are recognized by a commonly used anti-GFP antibody, and both variants can be immunoprecipitated using the GFP TRAP Camelidae antibody nanotrap technology. Because Envy is brighter than the other GFP variants and is as photostable as GFPγ, we suggest that Envy should be the preferred GFP variant, while Ivy may be used in cases where photostability is of the utmost importance.

  18. Construction of Fusion Expression Vector Carrying GFP and ZmCIPK

    Institute of Scientific and Technical Information of China (English)

    TAI Fu-ju; WANG Qi; WANG Wei; SHEN Teng-fei; LI Xiao

    2011-01-01

    [Objective] The aim was to isolate the CBL-interacting protein kinases (CIPK) from maize (Zea mays L. ) and construct the fusion gene expression vector which consisted the ZmCIPK8 and GFP. [Method] The ZmClPK8 cDNA was successfully cloned by using RT-PCR method. And then, it was connected to the pBlueScript SK (pSK) plasmid, which contained the GFP gene. So that the fusion gene vector pSKCIPK-GFP was obtained. Then, the fusion gene was connected into the efficient plant expression vector PB1121 to construct the fusion gene expression vector PBI-ClPK-GFP. At last, the recombined expression vector was transformed to Agrobacterium tumefaciems LBA4404 to produce the engineering strain LBA4404-PBI-ClPK-GFP. [Result] The fusion gene expression vector which consisted of GFP and ZmCIPKB gene and engineering strain LBA4404-PBI-ClPK-GFP were successfully constructed. [Conclusion] The results lays a foundation for further study of subcellular localization of ZmCIPK8, which can help to clarify the molecular mechanism of regulation serious stresses, and also provides an important basis for the research on resistance stress engineering of maize.

  19. Photoinduced activation of GFP-like proteins in tissues of reef corals

    Science.gov (United States)

    Salih, Anya; Wiedenmann, Joerg; Matz, Mikhail; Larkum, Anthony W.; Cox, Guy

    2006-02-01

    A variety of fluorescent and chromophoric proteins homologous to the green fluorescent protein (GFP) has been recently discovered and cloned from non-bioluminescent marine animals, such as corals, and now provide a multitude of colors for use in fluorescence imaging applications. Recently, a novel fluorescence imaging methodology has emerged that utilizes the unique photoactivatory property of several GFP-like proteins, which respond to irradiation by altering their optical properties, thereby providing a new spatio-temporal capability to the GFP-based imaging applications. During our studies of GFP-like proteins from the Great Barrier Reef corals, several novel photoactivatable (PA) GFP-like proteins have been discovered. These include fluorescence photo-amplifiers and reversible photoswitchers, similar to PA jelly-fish derived PA-GFP and Dronpa, that greatly increase their emissions following ultraviolet-A (UVA) irradiation; the red-to-green (R-to-G) converters, similar to DsRed, that rapidly change to green color following single- or 2-photon irradiation; the green-to-red (G-to-R) converters, that acquire bright red fluorescence following UV-violet irradiation, similar to Kaede-like proteins; and the kindling GFP-like proteins, that are non fluorescent, but rapidly acquire bright fluorescence after green light irradiation. We report on the various optical characteristics of these coral PA proteins that may be used to expand the scope of the available fluorescence bio-imaging technologies.

  20. A family of GFP-like proteins with different spectral properties in lancelet Branchiostoma floridae

    Directory of Open Access Journals (Sweden)

    Mushegian Arcady

    2008-07-01

    Full Text Available Abstract Background Members of the green fluorescent protein (GFP family share sequence similarity and the 11-stranded β-barrel fold. Fluorescence or bright coloration, observed in many members of this family, is enabled by the intrinsic properties of the polypeptide chain itself, without the requirement for cofactors. Amino acid sequence of fluorescent proteins can be altered by genetic engineering to produce variants with different spectral properties, suitable for direct visualization of molecular and cellular processes. Naturally occurring GFP-like proteins include fluorescent proteins from cnidarians of the Hydrozoa and Anthozoa classes, and from copepods of the Pontellidae family, as well as non-fluorescent proteins from Anthozoa. Recently, an mRNA encoding a fluorescent GFP-like protein AmphiGFP, related to GFP from Pontellidae, has been isolated from the lancelet Branchiostoma floridae, a cephalochordate (Deheyn et al., Biol Bull, 2007 213:95. Results We report that the nearly-completely sequenced genome of Branchiostoma floridae encodes at least 12 GFP-like proteins. The evidence for expression of six of these genes can be found in the EST databases. Phylogenetic analysis suggests that a gene encoding a GFP-like protein was present in the common ancestor of Cnidaria and Bilateria. We synthesized and expressed two of the lancelet GFP-like proteins in mammalian cells and in bacteria. One protein, which we called LanFP1, exhibits bright green fluorescence in both systems. The other protein, LanFP2, is identical to AmphiGFP in amino acid sequence and is moderately fluorescent. Live imaging of the adult animals revealed bright green fluorescence at the anterior end and in the basal region of the oral cirri, as well as weaker green signals throughout the body of the animal. In addition, red fluorescence was observed in oral cirri, extending to the tips. Conclusion GFP-like proteins may have been present in the primitive Metazoa. Their

  1. The effect of amino acid deletions and substitutions in the longest loop of GFP

    Directory of Open Access Journals (Sweden)

    Gaytán Paul

    2007-06-01

    Full Text Available Abstract Background The effect of single and multiple amino acid substitutions in the green fluorescent protein (GFP from Aequorea victoria has been extensively explored, yielding several proteins of diverse spectral properties. However, the role of amino acid deletions in this protein -as with most proteins- is still unknown, due to the technical difficulties involved in generating combinatorial in-phase amino acid deletions on a target region. Results In this study, the region I129-L142 of superglo GFP (sgGFP, corresponding to the longest loop of the protein and located far away from the central chromophore, was subjected to a random amino acid deletion approach, employing an in-house recently developed mutagenesis method termed Codon-Based Random Deletion (COBARDE. Only two mutants out of 16384 possible variant proteins retained fluorescence: sgGFP-Δ I129 and sgGFP-Δ D130. Interestingly, both mutants were thermosensitive and at 30°C sgGFP-Δ D130 was more fluorescent than the parent protein. In contrast with deletions, substitutions of single amino acids from residues F131 to L142 were well tolerated. The substitution analysis revealed a particular importance of residues F131, G135, I137, L138, H140 and L142 for the stability of the protein. Conclusion The behavior of GFP variants with both amino acid deletions and substitutions demonstrate that this loop is playing an important structural role in GFP folding. Some of the amino acids which tolerated any substitution but no deletion are simply acting as "spacers" to localize important residues in the protein structure.

  2. Studies of patulin diffusion in apple using a gfp transformant of Penicillium expansum

    DEFF Research Database (Denmark)

    Jensen, Birgit; Nielsen, Per Væggemose; Jensen, Dan Funck

    To study whether patulin diffuses in front of the pathogen or vice versa, we have inserted a constitutively expressed gfp-construct into Penicillium expansum. Spores and hyphal growth of the transformant IBT21525gfp4 in apple tissue was visualized directly by fluorescence mocroscopy. Using HPLC....../UV, patulin was detected in apparently sound tissue more than 2 cm from the edge of lesions caused by P. expansum wildtypes....

  3. GFP tracking transcriptional activity endogenous p53: vector construction and application in genotoxicity detection

    Institute of Scientific and Technical Information of China (English)

    ZENG Wei-sen; LUO Chen; XIE Wei-bing; CHEN Han-yuan

    2001-01-01

    To establish a sensitive.and specific system for genotoxicity detection in vivo. Methods: Endogenous p53 tracer vector p53RE was constructed by using green fluorescent protein (GFP) as a reporter to trace p53 transcriptional activity under the control of base SV40 early promoter. The tracer cells 3T3-REG were established by transfecting NIH3T3 cells with tracer vector and treated with ultraviolet, H202 and adriamycin to induce DNA damage and the subsequent endogenous p53 expression. The GFP expression and its green fluorescence in the tracer cells were observed and measured with fluorescent microscope and FACS. Results: The GFP expression increased rapidly after various treatment and reached the maximum 1 h later, and decreased gradually afterwards. FACS analysis showed that GFP expression in 3T3-REG tracer cells was consistent with the concentration of H202, while that in 3T3-SVG cells, which were transfected with control vector pSV-GFP, hardly increased in response to the treatment. Conclusion: GFP tracing p53 transcriptional activity is a sensitive and specific method for genotoxicity detection.

  4. Generating of rice OsCENH3-GFP transgenic plants and their genetic applications

    Institute of Scientific and Technical Information of China (English)

    YU HengXiu; WANG Xin; GONG ZhiYun; TANG Ding; GU MingHong; CHENG ZhuKuan

    2008-01-01

    In order to investigate rice functional centromeres, OsCENH3-GFP chimeric gene was constructed and transformed into the indica rice variety, Zhongxian 3037, mediated by Agrobacturium. The integration of the exogenous genes in the transgenic plants was confirmed by PCR and Southern blotting. The transgenic plants grow normally during their whole life time, just like Zhongxian 3037. No significant defects were detected in either mitosis or meiosis of the transgenic plants. The overlapping of GFP signals and anti-CENH3 foci in both mitotic and meiotic cells from To and T1 generation plants indicated that GFP had been successfully fused with CENH3, so the GFP signals can well represent the CENH3 locations on each chromosome. To evaluate the applicability of the transgenic plants to other genetic studies, fluorescence in situ hybridization (FISH) using rice centromeric tandem repetitive sequence CentO as the probe was conducted on the zygotene chromosomes of pollen mother cells (PMCs). It has been revealed that the GFP signals are overlapping with CentO FISH signals, showing that CentO is one of the key elements constituting rice functional centromeres. Immunofluorescent staining using anti-α-tublin antibody and anti-PAIR2 antibody on the chromosomes during mitosis and meiosis stages of the transgenic plants further reveals that OsCENH3-GFP transgenic plants can be widely used for studying rice molecular biology, especially for tagging functional centromeres in both living cells and tissues.

  5. Soluble expression and characterization of a GFP-fused pea actin isoform(PEAc1)

    Institute of Scientific and Technical Information of China (English)

    Ai Xiao LIU; Shao Bin ZHANG; Xiao Jing XU; Dong Tao REN; Guo Qin LIU

    2004-01-01

    A pea actin isoform PEAc1 with green fluorescent protein (GFP) fusion to its C-terminus and His-tag to its Nterminus, was expressed in prokaryotic cells in soluble form, and highly purified with Ni-Chelating SepharoseTM Fast Flow column. The purified fusion protein (PEAc1-GFP) efficiently inhibited DNase I activities before polymerization,and activated the myosin Mg-ATPase activities after polymerization. The PEAc 1-GFP also polymerized into green fluorescent filamentous structures with a critical concentration of 0.75 μM. These filamentous structures were labeled by TRITC-phalloidin, a specific agent for staining actin microfilaments, and identified as having 9 nm diameters by negative staining. These results indicated that PEAc1 preserved the essential characteristics of actin even with His-tag and GFP fusion, suggesting a promising potential to use GFP fusion protein in obtainning soluble plant actin isoform to analyze its physical and biochemical properties in vitro. The PEAc 1-GFP was also expressed in tobacco BY2 cells,which offers a new pathway for further studying its distribution and function in vivo.

  6. Analysis of cytoskeleton dynamics and cell migration in drosophila ovaries using GFP-actin and E-cadherin-GFP fusion molecules

    Science.gov (United States)

    Verkhusha, Vladyslav V.; Tsukita, Shoichiro; Oda, Hiroki

    1999-06-01

    Coordination of cell migration and adhesion is essential for movement of tissues during morphogenesis. During Drosophila oogenesis so called border cells (BCs) break from an anterior epithelium of egg chamber, acquire a mesenchymal-like morphology, and migrate posteriorly between nurse cells to oocyte. The confocal microscopic observation of BCs has revealed well-developed forepart lamellipodium stained with Drosophila E-cadherin (DE-cadherin), PS2 integrin, cytoplasmic myosin and F-actin. To investigate mechanism of BC migration in vivo we have constructed a DE-cadherin-GFP and a GFP-actin fusion proteins and induced their expression BCs utilizing the UAS/GAL4 system. The DE-cadherin-GFP signal as well as immunostaining of PS2 integrin visualized a track of migrating BCs providing an evidence that adhesive molecules are pulled out and left behind on the surface of nurse cells. Our data suggest that two distinct adhesive systems, DE-cadherins and PS2 integrins simultaneously mediate the migration of BCs. Release of adhesive contacts in the tail region is a rate- limited event in BC migration. The spatial-temporal sequence of actin-based events visualized by the GFP-actin suggest a treadmilling model for actin behavior in BC lamellipodium. BC migration can be considered as simultaneous reiterating processes of lamellipodium extension and adhesive attachment, cytoskeletal contraction, and rear detachment.

  7. GFP facilitates native purification of recombinant perlucin derivatives and delays the precipitation of calcium carbonate.

    Directory of Open Access Journals (Sweden)

    Eva Weber

    Full Text Available Insolubility is one of the possible functions of proteins involved in biomineralization, which often limits their native purification. This becomes a major problem especially when recombinant expression systems are required to obtain larger amounts. For example, the mollusc shell provides a rich source of unconventional proteins, which can interfere in manifold ways with different mineral phases and interfaces. Therefore, the relevance of such proteins for biotechnological processes is still in its infancy. Here we report a simple and reproducible purification procedure for a GFP-tagged lectin involved in biomineralization, originally isolated from mother-of-pearl in abalone shells. An optimization of E. coli host cell culture conditions was the key to obtain reasonable yields and high degrees of purity by using simple one-step affinity chromatography. We identified a dual functional role for the GFP domain when it became part of a mineralizing system in vitro. First, the GFP domain improved the solubility of an otherwise insoluble protein, in this case recombinant perlucin derivatives. Second, GFP inhibited calcium carbonate precipitation in a concentration dependent manner. This was demonstrated here using a simple bulk assay over a time period of 400 seconds. At concentrations of 2 µg/ml and higher, the inhibitory effect was observed predominantly for HCO(3 (- as the first ionic interaction partner, but not necessarily for Ca(2+. The interference of GFP-tagged perlucin derivatives with the precipitation of calcium carbonate generated different types of GFP-fluorescent composite calcite crystals. GFP-tagging offers therefore a genetically tunable tool to gently modify mechanical and optical properties of synthetic biocomposite minerals.

  8. Cytoplasmically Retargeted HSV1-tk/GFP Reporter Gene Mutants for Optimization of Noninvasive Molecular-Genetic Imaging

    Directory of Open Access Journals (Sweden)

    Vladimir Ponomarev

    2003-05-01

    Full Text Available To optimize the sensitivity of imaging HSV1-tk/GFP reporter gene expression, a series of HSV1-tk/GFP mutants was developed with altered nuclear localization and better cellular enzymatic activity, compared to that of the native HSV1-tk/GFP fusion protein (HSVi-tk/GFP. Several modifications of HSV1-tk/GFP reporter gene were performed, including targeted inactivating mutations in the nuclear localization signal (NLS, the addition of a nuclear export signal (NES, a combination of both mutation types, and a truncation of the first 135 by of the native hsvl-tk coding sequence containing a “cryptic” testicular promoter and the NLS. A recombinant HSV1-tk/GFP protein and a highly sensitive sandwich enzyme-linked immunosorbent assay for HSV1-tk/GFP were developed to quantitate the amount of reporter gene product in different assays to allow normalization of the data. These different mutations resulted in various degrees of nuclear clearance, predominant cytoplasmic distribution, and increased total cellular enzymatic activity of the HSV1-tk/GFP mutants, compared to native HSV1-tk/GFP when expressed at the same levels. This appears to be the result of improved metabolic bioavailability of cytoplasmically retargeted mutant HSV1-tk/GFP enzymes for reaction with the radiolabeled probe (e.g., FIAU. The analysis of enzymatic properties of different HSV1-tk/GFP mutants using FIAU as a substrate revealed no significant differences from that of the native HSV1-tk/GFP. Improved total cellular enzymatic activity of cytoplasmically retargeted HSV1-tk/GFP mutants observed in vitro was confirmed by noninvasive imaging of transduced subcutaneous tumor xenografts bearing these reporters using [131I]FIAU and γ-camera.

  9. Model system for plant cell biology: GFP imaging in living onion epidermal cells

    Science.gov (United States)

    Scott, A.; Wyatt, S.; Tsou, P. L.; Robertson, D.; Allen, N. S.

    1999-01-01

    The ability to visualize organelle localization and dynamics is very useful in studying cellular physiological events. Until recently, this has been accomplished using a variety of staining methods. However, staining can give inaccurate information due to nonspecific staining, diffusion of the stain or through toxic effects. The ability to target green fluorescent protein (GFP) to various organelles allows for specific labeling of organelles in vivo. The disadvantages of GFP thus far have been the time and money involved in developing stable transformants or maintaining cell cultures for transient expression. In this paper, we present a rapid transient expression system using onion epidermal peels. We have localized GFP to various cellular compartments (including the cell wall) to illustrate the utility of this method and to visualize dynamics of these compartments. The onion epidermis has large, living, transparent cells in a monolayer, making them ideal for visualizing GFP. This method is easy and inexpensive, and it allows for testing of new GFP fusion proteins in a living tissue to determine deleterious effects and the ability to express before stable transformants are attempted.

  10. A mRad51-GFP antimorphic allele affects homologous recombination and DNA damage sensitivity.

    Science.gov (United States)

    Uringa, Evert-Jan; Baldeyron, Céline; Odijk, Hanny; Wassenaar, Evelyne; van Cappellen, Wiggert A; Maas, Alex; Hoeijmakers, Jan H J; Baarends, Willy M; Kanaar, Roland; Essers, Jeroen

    2015-01-01

    Accurate DNA double-strand break repair through homologous recombination is essential for preserving genome integrity. Disruption of the gene encoding RAD51, the protein that catalyzes DNA strand exchange during homologous recombination, results in lethality of mammalian cells. Proteins required for homologous recombination, also play an important role during DNA replication. To explore the role of RAD51 in DNA replication and DSB repair, we used a knock-in strategy to express a carboxy-terminal fusion of green fluorescent protein to mouse RAD51 (mRAD51-GFP) in mouse embryonic stem cells. Compared to wild-type cells, heterozygous mRad51(+/wt-GFP) embryonic stem cells showed increased sensitivity to DNA damage induced by ionizing radiation and mitomycin C. Moreover, gene targeting was found to be severely impaired in mRad51(+/wt-GFP) embryonic stem cells. Furthermore, we found that mRAD51-GFP foci were not stably associated with chromatin. From these experiments we conclude that this mRad51-GFP allele is an antimorphic allele. When this allele is present in a heterozygous condition over wild-type mRad51, embryonic stem cells are proficient in DNA replication but display defects in homologous recombination and DNA damage repair. Copyright © 2014 Elsevier B.V. All rights reserved.

  11. Model system for plant cell biology: GFP imaging in living onion epidermal cells

    Science.gov (United States)

    Scott, A.; Wyatt, S.; Tsou, P. L.; Robertson, D.; Allen, N. S.

    1999-01-01

    The ability to visualize organelle localization and dynamics is very useful in studying cellular physiological events. Until recently, this has been accomplished using a variety of staining methods. However, staining can give inaccurate information due to nonspecific staining, diffusion of the stain or through toxic effects. The ability to target green fluorescent protein (GFP) to various organelles allows for specific labeling of organelles in vivo. The disadvantages of GFP thus far have been the time and money involved in developing stable transformants or maintaining cell cultures for transient expression. In this paper, we present a rapid transient expression system using onion epidermal peels. We have localized GFP to various cellular compartments (including the cell wall) to illustrate the utility of this method and to visualize dynamics of these compartments. The onion epidermis has large, living, transparent cells in a monolayer, making them ideal for visualizing GFP. This method is easy and inexpensive, and it allows for testing of new GFP fusion proteins in a living tissue to determine deleterious effects and the ability to express before stable transformants are attempted.

  12. Jellyifsh Green Fluorescent Protein (GFP) as a Reporter for Fusarium gramminearum Development on Wheat

    Institute of Scientific and Technical Information of China (English)

    QI Jun-xian; LIU Tai-guo; XU Ying; CHEN Huai-gu; GAO Li; LIU Bo; CHEN Wan-quan

    2014-01-01

    The plasmid pGPDGFP under the control of pgpdA promotor was used together with vector pAN7-1 containing the hygromycin resistance cassette to co-transform protoplasts of HG1, Fusarium graminearum from Hubei Province, China. Twelve out of 14 hygromycin-resistant transformants showed green signal under the UV light and contained one or several copies of gfp, as indicated by Southern analysis of genomic DNA digested with different restriction enzymes and hybridized to the gfp probe. A single gfp copy transformant (HG1C5) was selected for further evaluation of 80 Chinese wheat cultivars or advanced lines. The results showed different resistance type to F. graminearum were observed. GFP signals observed in the rachis and adjacent spikes of 70 Chinese wheat lines such as Chuanchongzu 104 indicated both type I (host resistance to the initial infection by the fungus) and type II (resistance to the spread of FHB symptoms within an infected spike) were not observed. While other 10 lines showed type II resistance to F. graminearum with GFP signals only in inoculated spikelets. Development of the mycelium can be intuitively observed and the resistance of wheat to F. graminearum can be identiifed at 7 days post inoculation (dpi) in this way. The results showed no differences were evaluated between the transformed HG1C5 and the non-transgene artiifcial inoculation by SAS paired chi-square test and McNemar’s test (P=0.0625).

  13. Development of a protease activity assay using heat-sensitive Tus-GFP fusion protein substrates.

    Science.gov (United States)

    Askin, Samuel P; Morin, Isabelle; Schaeffer, Patrick M

    2011-08-15

    Proteases are implicated in various diseases and several have been identified as potential drug targets or biomarkers. As a result, protease activity assays that can be performed in high throughput are essential for the screening of inhibitors in drug discovery programs. Here we describe the development of a simple, general method for the characterization of protease activity and its use for inhibitor screening. GFP was genetically fused to a comparatively unstable Tus protein through an interdomain linker containing a specially designed protease site, which can be proteolyzed. When this Tus-GFP fusion protein substrate is proteolyzed it releases GFP, which remains in solution after a short heat denaturation and centrifugation step used to eliminate uncleaved Tus-GFP. Thus, the increase in GFP fluorescence is directly proportional to protease activity. We validated the protease activity assay with three different proteases, i.e., trypsin, caspase 3, and neutrophil elastase, and demonstrated that it can be used to determine protease activity and the effect of inhibitors with small sample volumes in just a few simple steps using a fluorescence plate reader.

  14. Colonization of Madagascar periwinkle (Catharanthus roseus), by endophytes encoding gfp marker.

    Science.gov (United States)

    Torres, Adalgisa Ribeiro; Araújo, Welington Luiz; Cursino, Luciana; de Barros Rossetto, Priscilla; Mondin, Mateus; Hungria, Mariangela; Azevedo, João Lúcio

    2013-07-01

    This study reports the introduction of gfp marker in two endophytic bacterial strains (Pantoea agglomerans C33.1, isolated from cocoa, and Enterobacter cloacae PR2/7, isolated from citrus) to monitor the colonization in Madagascar perinwinkle (Catharanthus roseus). Stability of the plasmid encoding gfp was confirmed in vitro for at least 72 h of bacterial growth and after the colonization of tissues, under non-selective conditions. The colonization was observed using fluorescence microscopy and enumeration of culturable endophytes in inoculated perinwinkle plants that grew for 10 and 20 days. Gfp-expressing strains were re-isolated from the inner tissues of surface-sterilized roots and stems of inoculated plants, and the survival of the P. agglomerans C33:1gfp in plants 20 days after inoculation, even in the absence of selective pressure, suggests that is good colonizer. These results indicated that both gfp-tagged strains, especially P. agglomerans C33.1, may be useful tools to deliver enzymes or other proteins in plant.

  15. Efficient transformation and expression of gfp gene in the edible mushroom Pleurotus nebrodensis

    Institute of Scientific and Technical Information of China (English)

    Junfang Lin; Mingyao Zheng; Jie Wang; Wei Shu; Liqiong Guo

    2008-01-01

    An efficient transformation method mediated by PEG-protoplasts was developed for the newly commercial edible mushroom Pleu-rotus nebrodensis. Two plasmids were used to co-transform protoplasts of P. nebrodensis. One plasmid is pAN7-1 containing a positive selectable marker gene hph conferring hygromycin B resistance. Another plasmid is pBIue-GFP containing a reporter gene gfp conferring green fluorescent protein. PCR and Southern blot analysis showed that hph gene or/and gfp gene were integrated into the genome of P.nebrodensis transformants. The transformation efficiency of the positive selectable marker gene hph was 3 transformants per microgram of plasmid pAN7-1 DNA, which was about 30 times higher than that previously reported in thoroughly studied Pleurotus species such as Pleurotus ostreatus. The transformation efficiency of the reporter gene gfp was 9 transformants per microgram of plasmid pBlu-GFP DNA. The co-transformation efficiency was 23.68%. This is the first report that a "reporter" gene, green fluorescent protein gene can be successfully stably expressed in this Pleurotus species.

  16. The Influence of GFP Gene on Histology and Immunological Function of Nude Mouse with GFP%GFP转基因裸鼠脾脏组织学观察

    Institute of Scientific and Technical Information of China (English)

    方天; 赵志刚; 恽时锋; 尤金炜; 张立波; 陈涛; 田小芸; 刘彪; 吴正林; 许龙祥; 周森妹

    2012-01-01

    目的 探讨GFP基因导入对BALB/c荧光裸鼠脾脏组织学及免疫功能的影响.方法 取不同日龄(14日龄、28日龄、49日龄、70日龄)BALB/c荧光裸鼠及BALB/c普通裸鼠各32只,雌雄各半,处死取脾脏,对脾脏的绝对重量、脾脏指数进行测量分析,对脾脏的组织学改变进行观察,并对脾脏淋巴细胞数进行统计分析.结果 与14日龄荧光裸鼠相比,28日龄荧光裸鼠脾脏指数明显较高(P <0.05).与14日龄荧光裸鼠相比,49日龄、70日龄荧光裸鼠淋巴细胞数明显变少(P <0.05).与普通裸鼠(14日龄、28日龄、49日龄、70日龄)相比较,相同日龄荧光裸鼠(14日龄、28日龄、49日龄、70日龄)淋巴细胞数明显减少(P <0.05).结论 GFP基因对不同日龄荧光裸鼠的脾脏发育及其功能有一定影响.%Objective To explore the histological difference of spleen in BALB/c nude mouse with green fluorescent protein ( GFP) at different ages , and the effect of GFP gene on immune function . Method The spleens were gained, respectively, from 32 BALB/c nude mice with GFP and 32 BALB/c nude mice at assigned ages. The weight of spleen and spleen index were measured ; the histology changes of the spleen were observed under light microscope . The sum of lymphocyte cells were counted and analyzed . Results The spleen index of 28 days BALB/c nude mouse with GFP are higher significantly than 14 days. Compared with 14 days BALB/c nude mouse with GFP, the sum of lymphocyte cells of 49 days, 70 days are reduced significantly. The sum of lymphocyte cells of 14 days, 28 days, 49 days, 70 days BALB/ c nude mouse with GFP are higher significantly than 14 days, 28 days, 49 days, 70 days BALB/c nude mouse. Conclusion The GFP gene had some effect on the development and the immune function of the spleen in the BALB /c nude mouse with green fluorescent protein (GFP) at different ages.

  17. Experimental autoimmune uveoretinitis (EAU)-related tissue damage and angiogenesis is reduced in CCL2⁻/⁻CX₃CR1gfp/gfp mice.

    Science.gov (United States)

    Zhao, Jiawu; Chen, Mei; Xu, Heping

    2014-10-23

    To investigate the roles of the CCL2-CCR2 and CX₃CL1-CX₃CR1 pathways in experimental autoimmune uveoretinitis (EAU)-mediated retinal tissue damage and angiogenesis. The C57BL/6J wild-type (WT) and CCL2(-/-)CX₃CR1(gfp/gfp) (double knockout [DKO]) mice were immunized with IRBP₁₋₂₀. Retinal inflammation and tissue damage were evaluated clinically and histologically at different days postimmunization (p.i.). Retinal neovascular membranes were evaluated by confocal microscopy of retinal flat mounts, and immune cell infiltration by flow cytometry. At day 25 p.i., DKO mice had lower clinical and histological scores and fewer CD45(high)CD11b(+) infiltrating cells compared with WT mice. The F4/80(+) macrophages constitute 40% and 21% and CD11b(+)Gr-1(+)Ly6G(+) neutrophils constitute 10% and 22% of retinal infiltrating cells in WT and DKO mice, respectively. At the late stages of EAU (day 60-90 p.i.), DKO and WT mice had similar levels of inflammatory score. However, less structural damage and reduced angiogenesis were detected in DKO mice. Neutrophils were rarely detected in the inflamed retina in both WT and DKO mice. Macrophages and myeloid-derived suppressor cells (MDSCs) accounted for 8% and 3% in DKO EAU retina, and 19% and 10% in WT EAU retina; 71% of infiltrating cells were T/B-lymphocytes in DKO EAU retina and 50% in WT EAU retina. Experimental autoimmune uveoretinitis-mediated retinal tissue damage and angiogenesis is reduced in CCL2(-/-)CX₃CR1(gfp/gfp) mice. Retinal inflammation is dominated by neutrophils at the acute stage and lymphocytes at the chronic stage in these mice. Our results suggest that CCR2(+) and CX₃CR1(+) monocytes are both involved in tissue damage and angiogenesis in EAU. Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.

  18. Cocultures of GFP(+) -granule cells with GFP(-) -pyramidal cells and interneurons for the study of mossy fiber neurotransmission with paired recordings.

    Science.gov (United States)

    Osorio, Beatriz; León, Uriel; Galván, Emilio J; Gutiérrez, Rafael

    2013-04-01

    Synaptic transmission of the granule cells (GCs) via their axons, the mossy fibers (MFs), is traditionally studied on acutely prepared or cultured slices. Usually, extracellular, bulk or minimal stimulation is used to evoke transmitter release from MF terminals, while recording from their postsynaptic target cells, the pyramidal cells and interneurons of CA3. However, the ideal method to assess MF neurotransmission, the simultaneous recording of a presynaptic GC and one of its target cells, is extremely difficult to achieve using slices. Alternatively, cultures of GCs establishing autapses have been developed, but in these, GCs do not contact their natural targets. We developed cocultures of GCs, dissociated from transgenic GFP(+) rats, with pyramidal cells and interneurons of CA3, dissociated from wild-type rats, and confirmed the expression of cell-specific markers by immunofluorescence. We conducted recordings of GFP(+) -GCs synaptically connected with their GFP(-) -target cells, and demonstrate that synaptic transmission and its plasticity have the signature of transmission of MF. Besides being strongly depressed by activation of mGluRs, high frequency activation of GC-to-pyramidal cells synapses undergo LTP, while GC-to-interneuron synapses undergo LTD. This coculture method allows a high reproducibility of recording connected pairs of identified cells, constituting a valuable tool to study MF transmission, as well as different combinations of identifiable pre- and postsynaptic cells.

  19. HU-GFP and DAPI co-localize on the Escherichia coli nucleoid.

    Science.gov (United States)

    Wery, M; Woldringh, C L; Rouviere-Yaniv, J

    2001-02-01

    The heterodimeric HU protein, one of the most abundant DNA binding proteins, plays a pleiotropic role in bacteria. Among others, HU was shown to contribute to the maintenance of DNA superhelical density in Escherichia coli. By its properties HU shares some traits with histones and HMG proteins. More recently, its specific binding to DNA recombination and repair intermediates suggests that HU should be considered as a DNA damage sensor. For all these reasons, it will be of interest to follow the localization of HU within the living bacterial cells. To this end, we constructed HU-GFP fusion proteins and compared by microscopy the GFP green fluorescence with images of the nucleoid after DAPI staining. We show that DAPI and HU-GFP colocalize on the E. coli nucleoid. HU, therefore, can be considered as a natural tracer of DNA in the living bacterial cell.

  20. Establishment of Lactobacillus plantarum strain in honey bee digestive tract monitored using gfp fluorescence.

    Science.gov (United States)

    Javorský, P; Fecskeová, L Kolesár; Hrehová, L; Sabo, R; Legáth, J; Pristas, P

    2017-04-26

    Lactic acid bacteria are symbiotic bacteria that naturally reside in the gastrointestinal tract of honey bees. They serve a multitude of functions and are considered beneficial and completely harmless. In our experiments Lactobacillus plantarum strain B35, isolated from honey bee digestive tract, was modified using pAD43-25 plasmid carrying a functional GFP gene sequence (gfpmut3a) and used as a model for monitoring and optimisation of the mode of application. The establishment of this strain in honey bee digestive tract was monitored using GFP fluorescence. Three different modes of oral application of this strain were tested: water suspension of lyophilised bacteria, aerosol application of these bacteria and consumption of sugar honey paste containing the lyophilised lactobacilli. Two days after administration the L. plantarum B35-gfp was present throughout the honey bee digestive tract with 10(4)-10(5) cfu/bee with highest count observed for aerosol application.

  1. Protein-Protein Interaction Assays with Effector-GFP Fusions in Nicotiana benthamiana.

    Science.gov (United States)

    Petre, Benjamin; Win, Joe; Menke, Frank L H; Kamoun, Sophien

    2017-01-01

    Plant parasites secrete proteins known as effectors into host tissues to manipulate host cell structures and functions. One of the major goals in effector biology is to determine the host cell compartments and the protein complexes in which effectors accumulate. Here, we describe a five-step pipeline that we routinely use in our lab to achieve this goal, which consists of (1) Golden Gate assembly of pathogen effector-green fluorescent protein (GFP) fusions into binary vectors, (2) Agrobacterium-mediated heterologous protein expression in Nicotiana benthamiana leaf cells, (3) laser-scanning confocal microscopy assay, (4) anti-GFP coimmunoprecipitation-liquid chromatography-tandem mass spectrometry (coIP/MS) assay, and (5) anti-GFP western blotting. This pipeline is suitable for rapid, cost-effective, and medium-throughput screening of pathogen effectors in planta.

  2. Efficient expression of green fluorescent protein (GFP) mediated by a chimeric promoter in Chlamydomonas reinhardtii

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    To improve the expression efficiency of exogenous genes in Chlamydomonas reinhardtii, a high efficient expression vector was constructed. Green fluorescent protein (GFP) was expressed in C. Reinhardtii under the control of promoters: RBCS2 and HSP70A-RBCS2. Efficiency of transformation and expression were compared between two transgenic algae: RBCS2 mediated strain Tran-I and HSP70A-RBCS2 mediated strain Tran-II. Results show that HSP70A-RBCS2 could improve greatly the transformation efficiency by approximately eightfold of RBCS2, and the expression efficiency of GFP in Tran-II was at least double of that in Tran-I. In addition, a threefold increase of GFP in Tran-II was induced by heat shock at 40°C. All of the results demonstrated that HSP70A-RBCS2 was more efficient than RBCS2 in expressing exogenous gene in C. Reinhardtii.

  3. Rational Design of a GFP-Based Fluorogenic Caspase Reporter for Imaging Apoptosis In Vivo.

    Science.gov (United States)

    To, Tsz-Leung; Schepis, Antonino; Ruiz-González, Rubén; Zhang, Qiang; Yu, Dan; Dong, Zhiqiang; Coughlin, Shaun R; Shu, Xiaokun

    2016-07-21

    Fluorescence resonance energy transfer-based executioner caspase reporters using GFP are important tools for imaging apoptosis. While these reporters are useful for imaging apoptosis in cultured cells, their in vivo application has been handicapped by poor signal to noise. Here, we report the design and characterization of a GFP-based fluorogenic protease reporter, dubbed ZipGFP. ZipGFP-based TEV protease reporter increased fluorescence 10-fold after activation by protease. A ZipGFP-based executioner caspase reporter visualized apoptosis in live zebrafish embryos with spatiotemporal resolution. Thus, the ZipGFP-based caspase reporter may be useful for monitoring apoptosis during animal development and for designing reporters of proteases beyond the executioner caspases.

  4. Profiling of multiple signal pathway activities by multiplexing antibody and GFP-based translocation assays.

    Science.gov (United States)

    Henriksen, Ulla; Fog, Jacob; Loechel, Frosty; Praestegaard, Morten

    2008-08-01

    Multiplexing of GFP based and immunofluorescence translocation assays enables easy acquisition of multiple readouts from the same cell in a single assay run. Immunofluorescence assays monitor translocation, phosphorylation, and up/down regulation of endogenous proteins. GFP-based assays monitor translocation of stably expressed GFP-fusion proteins. Such assays may be multiplexed along (vertical), across (horizontal), and between (branch) signal pathways. Examples of these strategies are presented: 1) The MK2-GFP assay monitors translocation of MK2-GFP from the nucleus to the cytoplasm in response to stimulation of the p38 pathway. By applying different immunofluorescent assays to the MK2 assay, a multiplexed HCA system is created for deconvolution of p38 pathway activation including assay readouts for MK2, p38, NFkappaB, and c-Jun. 2) A method for evaluating GPCR activation and internalization in a single assay run has been established by multiplexing GFP-based internalization assays with immunofluorescence assays for downstream transducers of GPCR activity: pCREB (cAMP sensor), NFATc1 (Ca(2+) sensor), and ERK (G-protein activation). Activation of the AT1 receptor is given as an example. 3) Cell toxicity readouts can be linked to primary readouts of interest via acquisition of secondary parameters describing cellular morphology. This approach is used to flag cytotoxic compounds and deselect false positives. The ATF6 Redistribution assay is provided as an example. These multiplex strategies provide a unique opportunity to enhance HCA data quality and save time during drug discovery. From a single assay run, several assay readouts are obtained that help the user to deconvolute the mode of action of test compounds.

  5. Fusion to GFP blocks intercellular trafficking of the sucrose transporter SUT1 leading to accumulation in companion cells

    Directory of Open Access Journals (Sweden)

    Walsh Rama

    2003-12-01

    Full Text Available Abstract Background Plant phloem consists of an interdependent cell pair, the sieve element / companion cell complex. Sucrose transporters are localized to enucleate sieve elements (SE, despite being transcribed in companion cells (CC. Due to the high turnover of SUT1, sucrose transporter mRNA or protein must traffic from CC to SE via the plasmodesmata. Localization of SUT mRNA at plasmodesmatal orifices connecting CC and SE suggests RNA transport, potentially mediated by RNA binding proteins. In many organisms, polar RNA transport is mediated through RNA binding proteins interacting with the 3'-UTR and controlling localized protein synthesis. To study mechanisms for trafficking of SUT1, GFP-fusions with and without 3'-UTR were expressed in transgenic plants. Results In contrast to plants expressing GFP from the strong SUC2 promoter, in RolC-controlled expression GFP is retained in companion cells. The 3'-UTR of SUT1 affected intracellular distribution of GFP but was insufficient for trafficking of SUT1, GFP or their fusions to SEs. Fusion of GFP to SUT1 did however lead to accumulation of SUT1-GFP in the CC, indicating that trafficking was blocked while translational inhibition of SUT1 mRNA was released in CCs. Conclusion A fusion with GFP prevents targeting of the sucrose transporter SUT1 to the SE while leading to accumulation in the CC. The 3'-UTR of SUT1 is insufficient for mobilization of either the fusion or GFP alone. It is conceivable that SUT1-GFP protein transport through PD to SE was blocked due to the presence of GFP, resulting in retention in CC particles. Alternatively, SUT1 mRNA transport through the PD could have been blocked due to insertion of GFP between the SUT1 coding sequence and 3'-UTR.

  6. In Vivo Functional Brain Imaging Approach Based on Bioluminescent Calcium Indicator GFP-aequorin.

    Science.gov (United States)

    Lark, Arianna R; Kitamoto, Toshihiro; Martin, Jean-René

    2016-01-08

    Functional in vivo imaging has become a powerful approach to study the function and physiology of brain cells and structures of interest. Recently a new method of Ca(2+)-imaging using the bioluminescent reporter GFP-aequorin (GA) has been developed. This new technique relies on the fusion of the GFP and aequorin genes, producing a molecule capable of binding calcium and - with the addition of its cofactor coelenterazine - emitting bright light that can be monitored through a photon collector. Transgenic lines carrying the GFP-aequorin gene have been generated for both mice and Drosophila. In Drosophila, the GFP-aequorin gene has been placed under the control of the GAL4/UAS binary expression system allowing for targeted expression and imaging within the brain. This method has subsequently been shown to be capable of detecting both inward Ca(2+)-transients and Ca(2+)-released from inner stores. Most importantly it allows for a greater duration in continuous recording, imaging at greater depths within the brain, and recording at high temporal resolutions (up to 8.3 msec). Here we present the basic method for using bioluminescent imaging to record and analyze Ca(2+)-activity within the mushroom bodies, a structure central to learning and memory in the fly brain.

  7. Topology of Endoplasmic Reticulum-Associated Cellular and Viral Proteins Determined with Split-GFP.

    Science.gov (United States)

    Hyun, Seong-In; Maruri-Avidal, Liliana; Moss, Bernard

    2015-07-01

    The split green fluorescent protein (GFP) system was adapted for investigation of the topology of ER-associated proteins. A 215-amino acid fragment of GFP (S1-10) was expressed in the cytoplasm as a free protein or fused to the N-terminus of calnexin and in the ER as an intraluminal protein or fused to the C-terminus of calnexin. A 16-amino acid fragment of GFP (S11) was fused to the N- or C-terminus of the target protein. Fluorescence occurred when both GFP fragments were in the same intracellular compartment. After validation with the cellular proteins PDI and tapasin, we investigated two vaccinia virus proteins (L2 and A30.5) of unknown topology that localize to the ER and are required for assembly of the viral membrane. Our results indicated that the N- and C-termini of L2 faced the cytoplasmic and luminal sides of the ER, respectively. In contrast both the N- and C-termini of A30.5 faced the cytoplasm. The system offers advantages for quickly determining the topology of intracellular proteins: the S11 tag is similar in length to commonly used epitope tags; multiple options are available for detecting fluorescence in live or fixed cells; transfection protocols are adaptable to numerous expression systems and can enable high throughput applications.

  8. A Plasmodium falciparum strain expressing GFP throughout the parasite's life-cycle.

    Directory of Open Access Journals (Sweden)

    Arthur M Talman

    Full Text Available The human malaria parasite Plasmodium falciparum is responsible for the majority of malaria-related deaths. Tools allowing the study of the basic biology of P. falciparum throughout the life cycle are critical to the development of new strategies to target the parasite within both human and mosquito hosts. We here present 3D7HT-GFP, a strain of P. falciparum constitutively expressing the Green Fluorescent Protein (GFP throughout the life cycle, which has retained its capacity to complete sporogonic development. The GFP expressing cassette was inserted in the Pf47 locus. Using this transgenic strain, parasite tracking and population dynamics studies in mosquito stages and exo-erythrocytic schizogony is greatly facilitated. The development of 3D7HT-GFP will permit a deeper understanding of the biology of parasite-host vector interactions, and facilitate the development of high-throughput malaria transmission assays and thus aid development of new intervention strategies against both parasite and mosquito.

  9. Rapid induction of GFP expression by the nitrate reductase promoter in the diatom Phaeodactylum tricornutum

    Directory of Open Access Journals (Sweden)

    Lili Chu

    2016-08-01

    Full Text Available An essential prerequisite for a controlled transgene expression is the choice of a suitable promoter. In the model diatom Phaeodactylum tricornutum, the most commonly used promoters for trans-gene expression are the light dependent lhcf1 promoters (derived from two endogenous genes encoding fucoxanthin chlorophyll a/c binding proteins and the nitrate dependent nr promoter (derived from the endogenous nitrate reductase gene. In this study, we investigated the time dependent expression of the green fluorescent protein (GFP reporter under control of the nitrate reductase promoter in independently genetically transformed P. tricornutum cell lines following induction of expression by change of the nitrogen source in the medium via flow cytometry, microscopy and western blotting. In all investigated cell lines, GFP fluorescence started to increase 1 h after change of the medium, the fastest increase rates were observed between 2 and 3 h. Fluorescence continued to increase slightly for up to 7 h even after transfer of the cells to ammonium medium. The subsequent decrease of GFP fluorescence was much slower than the increase, probably due to the stability of GFP. The investigation of several cell lines transformed with nr based constructs revealed that, also in the absence of nitrate, the promoter may show residual activity. Furthermore, we observed a strong variation of gene expression between independent cell lines, emphasising the importance of a thorough characterisation of genetically modified cell lines and their individual expression patterns.

  10. Rosa26-GFP direct repeat (RaDR-GFP mice reveal tissue- and age-dependence of homologous recombination in mammals in vivo.

    Directory of Open Access Journals (Sweden)

    Michelle R Sukup-Jackson

    2014-06-01

    Full Text Available Homologous recombination (HR is critical for the repair of double strand breaks and broken replication forks. Although HR is mostly error free, inherent or environmental conditions that either suppress or induce HR cause genomic instability. Despite its importance in carcinogenesis, due to limitations in our ability to detect HR in vivo, little is known about HR in mammalian tissues. Here, we describe a mouse model in which a direct repeat HR substrate is targeted to the ubiquitously expressed Rosa26 locus. In the Rosa26 Direct Repeat-GFP (RaDR-GFP mice, HR between two truncated EGFP expression cassettes can yield a fluorescent signal. In-house image analysis software provides a rapid method for quantifying recombination events within intact tissues, and the frequency of recombinant cells can be evaluated by flow cytometry. A comparison among 11 tissues shows that the frequency of recombinant cells varies by more than two orders of magnitude among tissues, wherein HR in the brain is the lowest. Additionally, de novo recombination events accumulate with age in the colon, showing that this mouse model can be used to study the impact of chronic exposures on genomic stability. Exposure to N-methyl-N-nitrosourea, an alkylating agent similar to the cancer chemotherapeutic temozolomide, shows that the colon, liver and pancreas are susceptible to DNA damage-induced HR. Finally, histological analysis of the underlying cell types reveals that pancreatic acinar cells and liver hepatocytes undergo HR and also that HR can be specifically detected in colonic somatic stem cells. Taken together, the RaDR-GFP mouse model provides new understanding of how tissue and age impact susceptibility to HR, and enables future studies of genetic, environmental and physiological factors that modulate HR in mammals.

  11. Characterization of Annexin V Fusion with the Superfolder GFP in Liposomes Binding and Apoptosis Detection.

    Science.gov (United States)

    Abbady, Abdul Qader; Twair, Aya; Ali, Bouthaina; Murad, Hossam

    2017-01-01

    Programed cell death is a critical and unavoidable part of life. One of the most widely used markers for dying cells, by apoptosis or pyroptosis, is the redistribution of phosphatidylserine (PS) from the inner to the outer plasma membrane leaflet. Annexin V protein is a sensitive and specific probe to mark this event because of its high affinity to the exposed PS. Beyond that, annexin V can bind to any PS-containing phospholipid bilayer of almost all tiny forms of membranous vesicles like blood platelets, exosomes, or even nanostructured liposomes. In this work, recombinant human annexin V was produced as a fusion with a highly fluorescent superfolder derivative of the green fluorescent protein (sfGFP) in Escherichia coli. The fusion protein(sfGFP-ANXV, 64 kDa), annexin V (ANXV, 40 kDa), and sfGFP (27 kDa) were separately produced after cloning their encoding genes in pRSET plasmid, and all proteins were expressed in a soluble form, then purified in high yields because of their N-terminal 6× His tag (~150 mg of pure protein per 1 L culture). Superiority of this fluorescent fusion protein over fluorescein-conjugated annexin V was demonstrated in binding to phospholipids (and their liposomes), prepared from natural sources (soya bean and egg yolk) that have different content of PS, by using different methods including ELISA, dot-blotting, surface plasmon resonance, and flow cytometry. We also applied fluorescent annexin V in the detection of apoptotic cells by flow cytometry and fluorescent microscopy. Interestingly, sfGFP-ANXV fusion was more sensitive to early apoptotic stressed HeLa cells than fluorescein-conjugated-ANXV. This highly expressed and functional sfGFP-ANXV fusion protein provides a promising ready-to-use molecular tool for quantifying liposomes (or similarly exosomes) and detecting apoptosis in cells.

  12. Determination of the in vivo redox potential using roGFP and fluorescence spectra obtained from one-wavelength excitation

    Science.gov (United States)

    Wierer, S.; Elgass, K.; Bieker, S.; Zentgraf, U.; Meixner, A. J.; Schleifenbaum, F.

    2011-02-01

    The analysis of molecular processes in living (plant) cells such as signal transduction, DNA replication, carbon metabolism and senescence has been revolutionized by the use of green fluorescent protein (GFP) and its variants as specific cellular markers. Many cell biological processes are accompanied by changes in the intracellular redox potential. To monitor the redox potential, a redox-sensitive mutant of GFP (roGFP) was created, which shows changes in its optical properties in response to changes in the redox state of its surrounding medium. For a quantitative analysis in living systems, it is essential to know the optical properties of roGFP in vitro. Therefore, we applied spectrally resolved fluorescence spectroscopy on purified roGFP exposed to different redox potentials to determine shifts in both the absorption and the emission spectra of roGFP. Based on these in vitro findings, we introduce a new approach using one-wavelength excitation to use roGFP for the in vivo analysis of cell biological processes. We demonstrate the ability this technique by investigating chloroplast-located Grx1-roGFP2 expressing Arabidopsis thaliana cells as example for dynamically moving intracellular compartments. This is not possible with the two-wavelength excitation technique established so far, which hampers a quantitative analysis of highly mobile samples due to the time delay between the two measurements and the consequential displacement of the investigated area.

  13. Generation of Recombinant Rabies Virus CVS-11 Expressing eGFP Applied to the Rapid Virus Neutralization Test

    Directory of Open Access Journals (Sweden)

    Xianghong Xue

    2014-04-01

    Full Text Available The determination of levels of rabies virus-neutralizing antibody (VNA provides the foundation for the quantitative evaluation of immunity effects. The traditional fluorescent antibody virus neutralization test (FAVN using a challenge virus standard (CVS-11 strain as a detection antigen and staining infected cells with a fluorescein isothiocyanate (FITC-labeled monoclonal antibody, is expensive and high-quality reagents are often difficult to obtain in developing countries. Indeed, it is essential to establish a rapid, economical, and specific rabies virus neutralization test (VNT. Here, we describe a recombinant virus rCVS-11-eGFP strain that stably expresses enhanced green fluorescent protein (eGFP based on a reverse genetic system of the CVS-11 strain. Compared to the rCVS-11 strain, the rCVS-11-eGFP strain showed a similar growth property with passaging stability in vitro and pathogenicity in vivo. The rCVS-11-eGFP strain was utilized as a detection antigen to determine the levels of rabies VNAs in 23 human and 29 canine sera; this technique was termed the FAVN-eGFP method. The good reproducibility of FAVN-eGFP was tested with partial serum samples. Neutralization titers obtained from FAVN and FAVN-eGFP were not significantly different. The FAVN-eGFP method allows rapid economical, specific, and high-throughput assessment for the titration of rabies VNAs.

  14. Transient-state kinetic analysis of complex formation between photoprotein clytin and GFP from jellyfish Clytia gregaria

    NARCIS (Netherlands)

    Eremeeva, Elena V.; Berkel, Van Willem J.H.; Vysotski, Eugene S.

    2016-01-01

    Luminous organisms use different protein-mediated strategies to modulate light emission color. Here, we report the transient-state kinetic studies of the interaction between photoprotein clytin from Clytia gregaria and its antenna protein, cgreGFP. We propose that cgreGFP forms a transient comple

  15. Transient-state kinetic analysis of complex formation between photoprotein clytin and GFP from jellyfish Clytia gregaria

    NARCIS (Netherlands)

    Eremeeva, Elena V.; Berkel, Van Willem J.H.; Vysotski, Eugene S.

    2016-01-01

    Luminous organisms use different protein-mediated strategies to modulate light emission color. Here, we report the transient-state kinetic studies of the interaction between photoprotein clytin from Clytia gregaria and its antenna protein, cgreGFP. We propose that cgreGFP forms a transient

  16. Spontaneous silencing of humanized green fluorescent protein (hGFP) gene expression from a retroviral vector by DNA methylation

    DEFF Research Database (Denmark)

    Gram, G J; Nielsen, S D; Hansen, J E

    1998-01-01

    We have constructed a functional murine leukemia virus (MLV)-derived retroviral vector transducing two genes encoding the autofluorescent humanized green fluorescent protein (hGFP) and neomycin phosphotransferase (Neo). This was done to determine whether hGFP could function as a marker gene...... in a retroviral vector and to investigate the expression of genes in a retroviral vector. Surprisingly, clonal vector packaging cell lines showed variable levels of hGFP expression, and expression was detected in as few as 49% of the cells in a clonally derived culture. This indicated that hGFP expression...... was shown to increase the hGFP-expressing MT4 cells from either 10.4% to 11.6% or 3.7% to 4.8%, corresponding to an increase in observed transduction efficiencies of 12% and 30%, respectively. These results indicate that silencing of gene expression from a retroviral vector may result from DNA methylation...

  17. Agrobacterium-mediated transformation of creeping bentgrass using GFP as a reporter gene.

    Science.gov (United States)

    Yu, T T; Skinner, D Z; Liang, G H; Trick, H N; Huang, B; Muthukrishnan, S

    2000-01-01

    Creeping bentgrass (Agrostis palustris Huds.) is a cool season grass widely used on putting greens in golf courses. Transformation of creeping bentgrass has been conducted using microprojectile bombardment and protoplast electroporation. The objective of our study is to develop an alternative and more efficient approach in transforming the grass using Agrobacterium (strain EHA 101). This technique was effective in transforming 40-day old calli derived from mature seeds cultured on MS medium supplemented with 2,4-D, kinetin, and sucrose. Dozens of transgenic plants have been produced from two independent transformed calli. Presence of functional green fluorescence protein (GFP) was detected in leaves, stems, and roots of transgenic seedlings. Four putative transgenic plants and two control plants were randomly chosen and analyzed by Southern blot analysis. Bands corresponding to the GFP gene were clearly shown in transgenic plants. These results indicated that Agrobacterium transformation can successfully be applied to creeping bentgrass.

  18. IR-FEL-induced green fluorescence protein (GFP) gene transfer into plant cell

    CERN Document Server

    Awazu, K; Tamiya, E

    2002-01-01

    A Free Electron Laser (FEL) holds potential for various biotechnological applications due to its characteristics such as flexible wavelength tunability, short pulse and high peak power. We could successfully introduce the Green Fluorescent Protein (GFP) gene into tobacco BY2 cells by IR-FEL laser irradiation. The irradiated area of the solution containing BY2 cells and plasmid was about 0.1 mm sup 2. FEL irradiation at a wavelength of 5.75 and 6.1 mu m, targeting absorption by the ester bond of the lipid and the amide I bond of the protein, respectively, was shown to cause the introduction of the fluorescent dye into the cell. On the other hand, transient expression of the GFP fluorescence was only observed after irradiation at 5.75 mu m. The maximum transfer efficiency was about 0.5%.

  19. Evaluation of a GFP Report Gene Construct for Environmental Arsenic Detection

    Energy Technology Data Exchange (ETDEWEB)

    Roberto, F.F.; Barnes, J.M.; Bruhn, D.F.

    2002-03-28

    Detection of arsenic and other heavy metal contaminants in the environment is critical to ensuring safe drinking water and effective cleanup of historic activities that have led to widespread contamination of soil and groundwater. Biosensors have the potential to significantly reduce the costs associated with site characterization and long term environmental monitoring. By exploiting the highly selective and sensitive natural mechanisms by which bacteria and other living organisms respond to heavy metals, and fusing transcriptionally active components of these mechanisms to reporter genes, such as B-galactosidase, bacterial luciferase (lux), or green fluorescent protein (GFP) from marine jellyfish, it is possible to produce inexpensive, yet effective biosensors. This article describes the response to submicrogram quantities of arsenite and arsenate of a whole cell arsenic biosensor utilizing a GFP reporter gene.

  20. The hESC line Envy expresses high levels of GFP in all differentiated progeny.

    Science.gov (United States)

    Costa, Magdaline; Dottori, Mirella; Ng, Elizabeth; Hawes, Susan M; Sourris, Koula; Jamshidi, Pegah; Pera, Martin F; Elefanty, Andrew G; Stanley, Edouard G

    2005-04-01

    Human embryonic stem cells (hESCs) have been advanced as a potential source of cells for use in cell replacement therapies. The ability to identify hESCs and their differentiated progeny readily in transplantation experiments will facilitate the analysis of hESC potential and function in vivo. We have generated a hESC line designated 'Envy', in which robust levels of green fluorescent protein (GFP) are expressed in stem cells and all differentiated progeny.

  1. Cadophora finlandia and Phialocephala fortinii: Agrobacterium-mediated transformation and functional GFP expression.

    Science.gov (United States)

    Gorfer, Markus; Klaubauf, Sylvia; Bandian, Dragana; Strauss, Joseph

    2007-07-01

    Hygromycin B resistance was transferred to the sterile mycelia of Cadophora finlandia and Phialocephala fortinii by co-cultivation with Agrobacterium tumefaciens. Constitutively expressed green fluorescent protein (GFP) was also introduced using the same vector. Confocal laser scanning microscopy (CLSM) revealed strong fluorescence of transformants. Both traits were mitotically stable during one year of subculturing on non-selective growth medium. Southern blot analysis showed that the majority of the transformants contained single-copy integrations at random sites in the genome.

  2. Thermal stability of chemically denatured green fluorescent protein (GFP) A preliminary study

    Energy Technology Data Exchange (ETDEWEB)

    Nagy, Attila; Malnasi-Csizmadia, Andras; Somogyi, Bela; Lorinczy, Denes

    2004-02-09

    Green fluorescent protein (GFP) is a light emitter in the bioluminescence reaction of the jellyfish Aequorea victoria. The protein consist of 238 amino acids and produces green fluorescent light ({lambda}{sub max}=508 nm), when irradiated with near ultraviolet light. The fluorescence is due to the presence of chromophore consisting of an imidazolone ring, formed by a post-translational modification of the tripeptide -Ser{sup 65}-Tyr{sup 66}-Gly{sup 67}-, which buried into {beta}-barrel. GFP is extremely compact and heat stable molecule. In this work, we present data for the effect of chemical denaturing agent on the thermal stability of GFP. When denaturing agent is applied, global thermal stability and the melting point of the molecule is decreases, that can be monitored with differential scanning calorimetry. The results indicate, that in 1-6 M range of GuHCl the melting temperature is decreasing continuously from 83 to 38 deg. C. Interesting finding, that the calculated calorimetric enthalpy decreases with GuHCl concentration up to 3 M (5.6-0.2 kJ mol{sup -1}), but at 4 M it jumps to 8.4 and at greater concentration it is falling down to 1.1 kJ mol{sup -1}. First phenomena, i.e. the decrease of melting point with increasing GuHCl concentration can be easily explained by the effect of the extended chemical denaturation, when less and less amount of heat required to diminish the remaining hydrogen bonds in {beta}-barrel. The surprising increase of calorimetric enthalpy at 4 M concentration of GuHCl could be the consequence of a dimerization or a formation of stable complex between GFP and denaturing agent as well as a precipitation at an extreme GuHCl concentration. We are planning further experiments to elucidate fluorescent consequence of these processes.

  3. Development and validation of four Leishmania species constitutively expressing GFP protein. A model for drug discovery and disease pathogenesis studies.

    Science.gov (United States)

    Patel, Asha Parbhu; Deacon, Andrew; Getti, Giulia

    2014-04-01

    Green fluorescent protein (GFP)-parasite transfectants have been widely used as a tool for studying disease pathogenesis in several protozoan models and their application in drug screening assays has increased rapidly. In the past decade, the expression of GFP has been established in several Leishmania species, mostly for in vitro studies. The current work reports generation of four transgenic parasites constitutively expressing GFP (Leishmania mexicana, Leishmania aethiopica, Leishmania tropica and Leishmania major) and their validation as a representative model of infection. This is the first report where stable expression of GFP has been achieved in L. aethiopica and L. tropica. Integration of GFP was accomplished through homologous recombination of the expression construct, pRib1.2αNEOαGFP downstream of the 18S rRNA promoter in all species. A homogeneous and high level expression of GFP was detected in both the promastigote and the intracellular amastigote stages. All transgenic species showed the same growth pattern, ability to infect mammalian host cells and sensitivity to reference drugs as their wild type counterparts. All four transgenic Leishmania are confirmed as models for in vitro and possibly in vivo infections and represent an ideal tool for medium throughput testing of compound libraries.

  4. A novel binary T-vector with the GFP reporter gene for promoter characterization.

    Directory of Open Access Journals (Sweden)

    Shu-Ye Jiang

    Full Text Available Several strategies have been developed to clone PCR fragments into desired vectors. However, most of commercially available T-vectors are not binary vectors and cannot be directly used for Agrobacterium-mediated plant genetic transformation. In this study, a novel binary T-vector was constructed by integrating two AhdI restriction sites into the backbone vector pCAMBIA 1300. The T-vector also contains a GFP reporter gene and thus, can be used to analyze promoter activity by monitoring the reporter gene. On the other hand, identification and characterization of various promoters not only benefit the functional annotation of their genes but also provide alternative candidates to be used to drive interesting genes for plant genetic improvement by transgenesis. More than 1,000 putative pollen-specific rice genes have been identified in a genome-wide level. Among them, 67 highly expressed genes were further characterized. One of the pollen-specific genes LOC_Os10g35930 was further surveyed in its expression patterns with more details by quantitative real-time reverse-transcription PCR (qRT-PCR analysis. Finally, its promoter activity was further investigated by analyzing transgenic rice plants carrying the promoter::GFP cassette, which was constructed from the newly developed T-vector. The reporter GFP gene expression in these transgenic plants showed that the promoter was active only in mature but not in germinated pollens.

  5. Generation and characterization of neurogenin1-GFP transgenic medaka with potential for rapid developmental neurotoxicity screening

    Energy Technology Data Exchange (ETDEWEB)

    Fan Chunyang [Integrated Systems Toxicology and Toxicity Assessment Divisions, National Health and Environmental Effects Research Laboratory, US EPA, Research Triangle Park, NC 27711 (United States); Curriculum in Toxicology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599 (United States); Simmons, Steven O. [Integrated Systems Toxicology and Toxicity Assessment Divisions, National Health and Environmental Effects Research Laboratory, US EPA, Research Triangle Park, NC 27711 (United States); Law, Sheran H.W. [Environmental Sciences and Policy Division, Nicholas School of the Environment and Earth Sciences, Duke University, Durham, NC 27708 (United States); Jensen, Karl; Cowden, John [Integrated Systems Toxicology and Toxicity Assessment Divisions, National Health and Environmental Effects Research Laboratory, US EPA, Research Triangle Park, NC 27711 (United States); Hinton, David [Environmental Sciences and Policy Division, Nicholas School of the Environment and Earth Sciences, Duke University, Durham, NC 27708 (United States); Padilla, Stephanie [Integrated Systems Toxicology and Toxicity Assessment Divisions, National Health and Environmental Effects Research Laboratory, US EPA, Research Triangle Park, NC 27711 (United States); Ramabhadran, Ram, E-mail: Ram.Ramabhadran@gmail.com [Integrated Systems Toxicology and Toxicity Assessment Divisions, National Health and Environmental Effects Research Laboratory, US EPA, Research Triangle Park, NC 27711 (United States)

    2011-09-15

    Fish models such as zebrafish and medaka are increasingly used as alternatives to rodents in developmental and toxicological studies. These developmental and toxicological studies can be facilitated by the use of transgenic reporters that permit the real-time, noninvasive observation of the fish. Here we report the construction and characterization of transgenic medaka lines expressing green fluorescent protein (GFP) under the control of the zebrafish neurogenin 1 (ngn1) gene promoter. Neurogenin (ngn1) is a helix-loop-helix transcription factor expressed in proliferating neuronal progenitor cells early in neuronal differentiation and plays a crucial role in directing neurogenesis. GFP expression was detected from 24 h post-fertilization until hatching, in a spatial pattern consistent with the previously reported zebrafish ngn1 expression. Temporal expression of the transgene parallels the expression profile of the endogenous medaka ngn1 transcript. Further, we demonstrate that embryos from the transgenic line permit the non-destructive, real-time screening of ngn1 promoter-directed GFP expression in a 96-well format, enabling higher throughput studies of developmental neurotoxicants. This strain has been deposited with and maintained by the National BioResource Project and is available on request ( (http://www.shigen.nig.ac.jp/medaka/strainDetailAction.do?quickSearch=true and strainId=5660)).

  6. Interaction of PLP with GFP-MAL2 in the human oligodendroglial cell line HOG.

    Directory of Open Access Journals (Sweden)

    Raquel Bello-Morales

    Full Text Available The velocity of the nerve impulse conduction of vertebrates relies on the myelin sheath, an electrically insulating layer that surrounds axons in both the central and peripheral nervous systems, enabling saltatory conduction of the action potential. Oligodendrocytes are the myelin-producing glial cells in the central nervous system. A deeper understanding of the molecular basis of myelination and, specifically, of the transport of myelin proteins, will contribute to the search of the aetiology of many dysmyelinating and demyelinating diseases, including multiple sclerosis. Recent investigations suggest that proteolipid protein (PLP, the major myelin protein, could reach myelin sheath by an indirect transport pathway, that is, a transcytotic route via the plasma membrane of the cell body. If PLP transport relies on a transcytotic process, it is reasonable to consider that this myelin protein could be associated with MAL2, a raft protein essential for transcytosis. In this study, carried out with the human oligodendrocytic cell line HOG, we show that PLP colocalized with green fluorescent protein (GFP-MAL2 after internalization from the plasma membrane. In addition, both immunoprecipitation and immunofluorescence assays, indicated the existence of an interaction between GFP-MAL2 and PLP. Finally, ultrastructural studies demonstrated colocalization of GFP-MAL2 and PLP in vesicles and tubulovesicular structures. Taken together, these results prove for the first time the interaction of PLP and MAL2 in oligodendrocytic cells, supporting the transcytotic model of PLP transport previously suggested.

  7. Low-Cost Synthesis of Smart Biocompatible Graphene Oxide Reduced Species by Means of GFP.

    Science.gov (United States)

    Masullo, Tiziana; Armata, Nerina; Pendolino, Flavio; Colombo, Paolo; Lo Celso, Fabrizio; Mazzola, Salvatore; Cuttitta, Angela

    2016-02-01

    The aim of this work is focused on the engineering of biocompatible complex systems composed of an inorganic and bio part. Graphene oxide (GO) and/or graphite oxide (GtO) were taken into account as potential substrates to the linkage of the protein such as Anemonia sulcata recombinant green fluorescent protein (rAsGFP). The complex system is obtained through a reduction process between GO/GtO and rAsGFP archiving an environmentally friendly biosynthesis. Spectroscopic measurements support the formation of reduced species. In particular, photoluminescence shows a change in the activity of the protein when a bond is formed, highlighted by a loss of the maximum emission signal of rAsGFP and a redshift of the maximum absorption peak of the GO/GtO species. Moreover, the hemolysis assay reveals a lower value in the presence of less oxidized graphene species providing evidence for a biocompatible material. This singular aspect can be approached as a promising method for circulating pharmaceutical preparations via intravenous administration in the field of drug delivery.

  8. GFP-based fluorescence assay for CAG repeat instability in cultured human cells.

    Directory of Open Access Journals (Sweden)

    Beatriz A Santillan

    Full Text Available Trinucleotide repeats can be highly unstable, mutating far more frequently than point mutations. Repeats typically mutate by addition or loss of units of the repeat. CAG repeat expansions in humans trigger neurological diseases that include myotonic dystrophy, Huntington disease, and several spinocerebellar ataxias. In human cells, diverse mechanisms promote CAG repeat instability, and in mice, the mechanisms of instability are varied and tissue-dependent. Dissection of mechanistic complexity and discovery of potential therapeutics necessitates quantitative and scalable screens for repeat mutation. We describe a GFP-based assay for screening modifiers of CAG repeat instability in human cells. The assay exploits an engineered intronic CAG repeat tract that interferes with expression of an inducible GFP minigene. Like the phenotypes of many trinucleotide repeat disorders, we find that GFP function is impaired by repeat expansion, in a length-dependent manner. The intensity of fluorescence varies inversely with repeat length, allowing estimates of repeat tract changes in live cells. We validate the assay using transcription through the repeat and engineered CAG-specific nucleases, which have previously been reported to induce CAG repeat instability. The assay is relatively fast and should be adaptable to large-scale screens of chemical and shRNA libraries.

  9. Detection of Autophagy in Caenorhabditis elegans Using GFP::LGG-1 as an Autophagy Marker.

    Science.gov (United States)

    Palmisano, Nicholas J; Meléndez, Alicia

    2016-01-04

    In yeast and mammalian cells, the autophagy protein Atg8/LC3 (microtubule-associated proteins 1A/1B light chain 3B encoded by MAP1LC3B) has been the marker of choice to detect double-membraned autophagosomes that are produced during the process of autophagy. A lipid-conjugated form of Atg8/LC3B is localized to the inner and outer membrane of the early-forming structure known as the phagophore. During maturation of autophagosomes, Atg8/LC3 bound to the inner autophagosome membrane remains in situ as the autophagosomes fuse with lysosomes. The nematode Caenorhabditis elegans is thought to conduct a similar process, meaning that tagging the nematode ortholog of Atg8/LC3-known as LGG-1-with a fluorophore has become a widely accepted method to visualize autophagosomes. Under normal growth conditions, GFP-modified LGG-1 displays a diffuse expression pattern throughout a variety of tissues, whereas, when under conditions that induce autophagy, the GFP::LGG-1 tag labels positive punctate structures, and its overall level of expression increases. Here, we present a protocol for using fluorescent reporters of LGG-1 coupled to GFP to monitor autophagosomes in vivo. We also discuss the use of alternative fluorescent markers and the possible utility of the LGG-1 paralog LGG-2.

  10. Application of GFP technique for cytoskeleton visualization onboard the International Space Station.

    Science.gov (United States)

    Kordyum, E L; Shevchenko, G V; Yemets, A I; Nyporko, A I; Blume, Ya B

    2005-03-01

    Cytoskeleton recently attracted wide attention of cell and molecular biologists due to its crucial role in gravity sensing and trunsduction. Most of cytoskeletal research is conducted by the means of immunohistochemical reactions, different modifications of which are beneficial for the ground-based experiments. But for the performance onboard the space vehicles, they represent quite complicated technique which requires time and special skills for astronauts. In addition, immunocytochemistry provides only static images of the cytoskeleton arrangement in fixed cells while its localization in living cells is needed for the better understanding of cytoskeletal function. In this connection, we propose a new approach for cytoskeletal visualization onboard the ISS, namely, application of green fluorescent protein (GFP) from Aequorea victoria, which has the unique properties as a marker for protein localization in vivo. The creation of chimerical protein-GFP gene constructs, obtaining the transformed plant cells possessed protein-GFP in their cytoskeletal composition will allow receiving a simple and efficient model for screening of the cytoskeleton functional status in microgravity.

  11. Clonal and territorial development of the pancreas as revealed by eGFP-labelled mouse chimeras.

    Science.gov (United States)

    Eberhard, Daniel; Jockusch, Harald

    2010-10-01

    The clonal structure of the pancreas was analysed in neonatal and adult mouse chimeras in which one partner displayed cell patches expressing green fluorescent protein (eGFP). Coherent growth during pancreatic histogenesis was suggested by the presence of large eGFP-labelled acinar clusters rather than a scattered distribution of individual labelled acinar cells. The adult chimeric pancreas contained monophenotypic acini, whereas surprisingly 5% of acini in neonates were polyclonal. Monophenotypic acini presumably arose by coherent expansion leading to large 3D patches and may not be monoclonal. Islets of Langerhans were oligoclonal at both ages investigated. The proportion of eGFP positive cells within islets did not correlate with that of the surrounding acinar tissue indicating clonal independence of islets from their neighbourhood. The patterns observed argue against a secondary contribution of blood-borne progenitor/stem cells to the acinar compartment during tissue turnover. The different clonal origins of acini and islets are integrated into a model of pancreatic histogenesis.

  12. Structural stability and endonuclease activity of a PI-SceI GFP-fusion protein

    Directory of Open Access Journals (Sweden)

    Alireza G. Senejani, J. Peter Gogarten

    2007-01-01

    Full Text Available Homing endonucleases are site-specific and rare cutting endonucleases often encoded by intron or intein containing genes. They lead to the rapid spread of the genetic element that hosts them by a process termed 'homing'; and ultimately the allele containing the element will be fixed in the population. PI-SceI, an endonuclease encoded as a protein insert or intein within the yeast V-ATPase catalytic subunit encoding gene (vma1, is among the best characterized homing endonucleases. The structures of the Sce VMA1 intein and of the intein bound to its target site are known. Extensive biochemical studies performed on the PI-SceI enzyme provide information useful to recognize critical amino acids involved in self-splicing and endonuclease functions of the protein. Here we describe an insertion of the Green Fluorescence Protein (GFP into a loop which is located between the endonuclease and splicing domains of the Sce VMA1 intein. The GFP is functional and the additional GFP domain does not prevent intein excision and endonuclease activity. However, the endonuclease activity of the newly engineered protein was different from the wild-type protein in that it required the presence of Mn2+ and not Mg2+ metal cations for activity.

  13. Expression of Green Fluorescent Protein (GFP using In Vitro translation cell free system

    Directory of Open Access Journals (Sweden)

    M Mohamadipoor

    2009-03-01

    Full Text Available ABSTRACT Background and the purpose of the study: One of the major concerns about recombinant protein production is its possible toxicity for the organism. Purification of the recombinant protein is another challenge in this respect. Recently In Vitro translation cell free system that provides a coupled transcription-translation reaction for protein synthesis to overcome the above mentioned problems has been emerged. The aim of this study was expression of GFP as a marker for gene expression and protein in In Vitro translation system. Methods: pIVEX2.3-GFP plasmid was cloned to E. coli   and the plasmid DNA extracted. In Vitro translation was performed with RTS 100 E. coli Hy kit according to manufacture's instructions. Expression of recombinant fusion protein, His- GFP, was determined by SDS-PAGE, ELISA and western blot analysis. Results: Expected size of recombinant protein was detected in SDS-PAGE and further confirmed by western blot analysis and ELISA. Major conclusion: Results showed that In Vitro translation is suitable for expression of recombinant protein and fusion of the recombinant protein with His-tag facilitates the purification.

  14. Expression of Chlamydomonas actin-gfp fusion gene in to-bacco suspension cell and polymerization of the actin-gfp protein in vitro

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The fusion gene of actin (cDNA of Chlamydo- monas reinhardtii) and green fluorescence protein (gfp) had been constructed into two expression vectors which could be expressed in E. coli and tobacco suspension cells BY2. The correct expression was observed in E. coli and BY2 with a fluorescence microscopy. The fusion protein, which took part in the membrane skeleton, was mainly located peripherally along the membrane, specially the fusion protein was dis-tributed around nucleus and cell plate, while the fusion pro-tein also forms F-actin in the cell. The fusion protein was purified from Bl21plus by ammonium sulfate fractionation, ion exchange chromatography and hydrophobic interaction chromatography. The purified production could polymerize into F-actin when the actin polymerizing buffer was added. It was demonstrated that the characteristics and function of actin in Chlamydomonas was similar with those of animals and higher plants.

  15. Temperature Influences on the Expression of GFP Promoted by the Upstream Sequence of cpcB from Arthrospira platensis

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    In order to investigate the regulation mechanism of the phycocyanin gene, a series of functional analyses of the upstream sequence of cpcB gene from Arthrospira platensis were conducted in E. coli with green fluorescent protein encoding gene (gfp) as the reporter. Results showed that the gfp gene could express at a high level under the promotion of the upstream sequence, suggesting the existence of some strong promoter elements in it. The expression of GFP was influenced by temperature. Higher temperature led to higher expression level. The bioinformatics analyses followed by mutation analyses on the secondary structure of translation initiation region (TIR) revealed that RNA thermosensor might account for the temperature regulation.

  16. Temperature influences on the expression of GFP promoted by the upstream sequence of cpcB from Arthrospira platensis

    Science.gov (United States)

    Lu, Yongzhong; Zhang, Xuecheng

    2007-07-01

    In order to investigate the regulation mechanism of the phycocyanin gene, a series of functional analyses of the upstream sequence of cpcB gene from Arthrospira platensis were conducted in E. coli with green fluorescent protein encoding gene (gfp) as the reporter. Results showed that the gfp gene could express at a high level under the promotion of the upstream sequence, suggesting the existence of some strong promoter elements in it. The expression of GFP was influenced by temperature. Higher temperature led to higher expression level. The bioinformatics analyses followed by mutation analyses on the secondary structure of translation initiation region (TIR) revealed that RNA thermosensor might account for the temperature regulation.

  17. Assessment of GFP expression and viability using the tali image-based cytometer.

    Science.gov (United States)

    Remple, Krissy; Stone, Laurel

    2011-11-17

    Single-cell and population information are commonly obtained either by flow cytometry or fluorescence microscopy. However, these two methods provide different information. Flow cytometry gives quantitative multi-parametric information about physical characteristics and staining or expression, but doesn't allow for visualization. Stand-alone fluorescence microscopy provides visual data, but doesn't allow for straightforward quantitative measurements(1). Image-based cytometry bridges the gap between these two methods, enabling the quick visualization and simultaneous quantitative analysis of thousands of cells in heterogeneous populations(2). Here, we present a method for performing cell viability and green fluorescent protein (GFP) expression assays using the Tali Image-Based Cytometer(3). The Tali instrument is a 3-channel (bright field, green fluorescence, red fluorescence) benchtop assay platform that offers several advantages over flow cytometry and fluorescence microscopy. The Tali cytometer is less expensive, takes up less bench space, requires less maintenance, and the work flow has been simplified so that the operation and analysis is much simpler and quicker. The Tali cytometer is capable of performing a range of suspension cell-based assays, including GFP and red fluorescent protein (RFP) expression, apoptosis(4-6) and cell viability analysis with propidium iodide (PI)(7-11). Here, we demonstrate the use of the Tali instrument in performing a cell viability assay in cells expressing GFP. GFP-transduced cells are stained using the Tali Viability Kit - Dead Cell Red. The cells are then pipetted into a Tali Cellular Analysis Slide and loaded into the cytometer. Bright field, red fluorescence and green fluorescence images are captured and analyzed using assay specific algorithms. Histograms are then generated to display cell size, PI fluorescence intensity, and GFP fluorescence intensity. These parameters can then be thresholded to home in on a specific cell

  18. An intein with genetically selectable markers provides a new approach to internally label proteins with GFP

    Directory of Open Access Journals (Sweden)

    Davis Trisha N

    2011-06-01

    Full Text Available Abstract Background Inteins are proteins that catalyze their own removal from within larger precursor proteins. In the process they splice the flanking protein sequences, termed the N-and C-terminal exteins. Large inteins frequently have a homing endonuclease that is involved in maintaining the intein in the host. Splicing and nuclease activity are independent and distinct domains in the folded structure. We show here that other biochemical activities can be incorporated into an intein in place of the endonuclease without affecting splicing and that these activities can provide genetic selection for the intein. We have coupled such a genetically marked intein with GFP as the N-terminal extein to create a cassette to introduce GFP within the interior of a targeted protein. Results The Pch PRP8 mini-intein of Penicillium chrysogenum was modified to include: 1 aminoglycoside phosphotransferase; 2 imidazoleglycerol-phosphate dehydratase, His5 from S. pombe ; 3 hygromycin B phosphotransferase; and 4 the transcriptional activator LexA-VP16. The proteins were inserted at the site of the lost endonuclease. When expressed in E. coli, all of the modified inteins spliced at high efficiency. Splicing efficiency was also greater than 96% when expressed from a plasmid in S. cerevisiae. In addition the inteins conferred either G418 or hygromycin resistance, or histidine or leucine prototropy, depending on the inserted marker and the yeast genetic background. DNA encoding the marked inteins coupled to GFP as the N-terminal extein was PCR amplified with ends homologous to an internal site in the yeast calmodulin gene CMD1. The DNA was transformed into yeast and integrants obtained by direct selection for the intein's marker. The His5-marked intein yielded a fully functional calmodulin that was tagged with GFP within its central linker. Conclusions Inteins continue to show their flexibility as tools in molecular biology. The Pch PRP8 intein can successfully

  19. The Zebrafish Anillin-eGFP Reporter Marks Late Dividing Retinal Precursors and Stem Cells Entering Neuronal Lineages

    Science.gov (United States)

    Guglielmi, Luca; Patzel, Eva; Sel, Saadettin; Auffarth, Gerd U.; Carl, Matthias; Poggi, Lucia

    2017-01-01

    Monitoring cycling behaviours of stem and somatic cells in the living animal is a powerful tool to better understand tissue development and homeostasis. The tg(anillin:anillin-eGFP) transgenic line carries the full-length zebrafish F-actin binding protein Anillin fused to eGFP from a bacterial artificial chromosome (BAC) containing Anillin cis-regulatory sequences. Here we report the suitability of the Anillin-eGFP reporter as a direct indicator of cycling cells in the late embryonic and post-embryonic retina. We show that combining the anillin:anillin-eGFP with other transgenes such as ptf1a:dsRed and atoh7:gap-RFP allows obtaining spatial and temporal resolution of the mitotic potentials of specific retinal cell populations. This is exemplified by the analysis of the origin of the previously reported apically and non-apically dividing late committed precursors of the photoreceptor and horizontal cell layers. PMID:28107513

  20. A novel subset of enteric neurons revealed by ptf1a:GFP in the developing zebrafish enteric nervous system.

    Science.gov (United States)

    Uribe, Rosa A; Gu, Tiffany; Bronner, Marianne E

    2016-03-01

    The enteric nervous system, the largest division of the peripheral nervous system, is derived from vagal neural crest cells that invade and populate the entire length of the gut to form diverse neuronal subtypes. Here, we identify a novel population of neurons within the enteric nervous system of zebrafish larvae that express the transgenic marker ptf1a:GFP within the midgut. Genetic lineage analysis reveals that enteric ptf1a:GFP(+) cells are derived from the neural crest and that most ptf1a:GFP(+) neurons express the neurotransmitter 5HT, demonstrating that they are serotonergic. This transgenic line, Tg(ptf1a:GFP), provides a novel neuronal marker for a subpopulation of neurons within the enteric nervous system, and highlights the possibility that Ptf1a may act as an important transcription factor for enteric neuron development.

  1. Cloned s-Lap Gene Coding Area, Expression and Localizationof s-Lap/GFP Fusion Protein in Mammal Cells

    Institute of Scientific and Technical Information of China (English)

    SONG Yi-shu; SONG Zhi-yu; LI Hong-jun; Wu Yin; BAO Yong-li; TAN Da-peng; LI Yu-xin

    2005-01-01

    s-Lap is a new gene sequence from pig retinal pigment epithelial(RPE) cells, which was found and cloned in the early period of apoptosis of RPE cells damaged with visible light. We cloned the coding area sequence of the novel gene of s-Lap and constructed its recombinant eukaryotic plasmid pcDNA3.1-GFP/s-lap with the recombinant DNA technique. The expression and localization of s-lap/GFP fusion protein in CHO and B16 cell lines were studied with the instantaneously transfected pcDNA3.1-GFP/s-lap recombinant plasmid. s-Lap/GFP fusion protein can be expressed in CHO and B16 cells with a high rate expression in the nuclei.

  2. Screening Estrogenic Activities of Chemicals or Mixtures In Vivo Using Transgenic (cyp19a1b-GFP) Zebrafish Embryos

    OpenAIRE

    François Brion; Yann Le Page; Benjamin Piccini; Olivier Cardoso; Sok-Keng Tong; Bon-chu Chung; Olivier Kah

    2012-01-01

    International audience; The tg(cyp19a1b-GFP) transgenic zebrafish expresses GFP (green fluorescent protein) under the control of the cyp19a1b gene, encoding brain aromatase. This gene has two major characteristics: (i) it is only expressed in radial glial progenitors in the brain of fish and (ii) it is exquisitely sensitive to estrogens. Based on these properties, we demonstrate that natural or synthetic hormones (alone or in binary mixture), including androgens or progestagens, and industria...

  3. Matrix metalloproteinase 2 fused to GFP, expressed in E. coli, successfully tracked MMP-2 distribution in vivo.

    Science.gov (United States)

    Azevedo, A; Prado, A F; Issa, J P M; Gerlach, R F

    2016-08-01

    Matrix Metalloproteinases (MMPs) participate in many physiological and pathological processes. One major limitation to a better understanding of the role MMPs play in these processes is the lack of well-characterized chimeric proteins and characterization of their fluorescence. The specialized literature has reported on few constructs bearing MMPs fused to the sequence of the green fluorescent protein (GFP), but none of the described constructs have been intended for expression in bacteria or for purification and use in vivo. This work has tested a recombinant reporter protein containing the MMP-2 catalytic domain fused to GFP in terms of purification efficiency, degradation of substrates in solution and in zymograms, kinetic activity, GFP fluorescence, and GFP fluorescence in whole animals after injection of the purified and lyophilized fluorescent protein. This work has also characterized rhMMP-2 (recombinant human MMP-2) and inactive clones and used them as negative controls in experiments employing catMMP-2/GFP and rhMMP-2. To our knowledge, this is the first study that has fully characterized a chimeric protein with the MMP-2 catalytic domain fused to GFP, that has efficiently purified such protein from bacteria in a single-step, and that has obtained an adequate chimeric protein for injection in animals and tracking of MMP-2 fate and activity in vivo.

  4. Isolation, plant colonization potential, and phenanthrene degradation performance of the endophytic bacterium Pseudomonas sp. Ph6-gfp

    Science.gov (United States)

    Sun, Kai; Liu, Juan; Gao, Yanzheng; Jin, Li; Gu, Yujun; Wang, Wanqing

    2014-06-01

    This investigation provides a novel method of endophyte-aided removal of polycyclic aromatic hydrocarbons (PAHs) from plant bodies. A phenanthrene-degrading endophytic bacterium Pseudomonas sp. Ph6 was isolated from clover (Trifolium pratense L.) grown in a PAH-contaminated site. After being marked with the GFP gene, the colonization and distribution of strain Ph6-gfp was directly visualized in plant roots, stems, and leaves for the first time. After ryegrass (Lolium multiflorum Lam.) roots inoculation, strain Ph6-gfp actively and internally colonized plant roots and transferred vertically to the shoots. Ph6-gfp had a natural capacity to cope with phenanthrene in vitro and in planta. Ph6-gfp degraded 81.1% of phenanthrene (50 mg.L-1) in a culture solution within 15 days. The inoculation of plants with Ph6-gfp reduced the risks associated with plant phenanthrene contamination based on observations of decreased concentration, accumulation, and translocation factors of phenanthrene in ryegrass. Our results will have important ramifications in the assessment of the environmental risks of PAHs and in finding ways to circumvent plant PAH contamination.

  5. In Vivo Direct Molecular Imaging of Early Tumorigenesis and Malignant Progression Induced by Transgenic Expression of GFP-Met

    Directory of Open Access Journals (Sweden)

    Sharon Moshitch-Moshkovitz

    2006-05-01

    Full Text Available The tyrosine kinase receptor Met and its ligand, hepatocyte growth factor/scatter factor (HGF/SF, play an important role in normal developmental processes, as well as in tumorigenicity and metastasis. We constructed a green fluorescent protein (GFP Met chimeric molecule that functions similarly to the wild-type Met receptor and generated GFP-Met transgenic mice. These mice ubiquitously expressed GFP-Met in specific epithelial and endothelial cells and displayed enhanced GFP-Met fluorescence in sebaceous glands. Thirty-two percent of males spontaneously developed adenomas, adenocarcinomas, and angiosarcomas in their lower abdominal sebaceous glands. Approximately 70% of adenocarcinoma tumors metastasized to the kidneys, lungs, or liver. Quantitative subcellularresolution intravital imaging revealed very high levels of GFP-Met in tumor lesions and in single isolated cells surrounding them, relative to normal sebaceous glands. These single cells preceded the formation of local and distal metastases. Higher GFP-Met levels correlated with earlier tumor onset and aggressiveness, further demonstrating the role of Met-HGF/SF signaling in cellular transformation and acquisition of invasive and metastatic phenotypes. Our novel mouse model and high-resolution intravital molecular imaging create a powerful tool that enables direct realtime molecular imaging of receptor expression and localization during primary events of tumorigenicity and metastasis at single-cell resolution.

  6. No adverse effects of transgenic maize on population dynamics of endophytic Bacillus subtilis strain B916-gfp.

    Science.gov (United States)

    Sun, Chongsi; Geng, Lili; Wang, Meiling; Shao, Gaoxiang; Liu, Yongfeng; Shu, Changlong; Zhang, Jie

    2017-02-01

    Endophytic bacterial communities play a key role in promoting plant growth and combating plant diseases. However, little is known about their population dynamics in plant tissues and bulk soil, especially in transgenic crops. This study investigated the colonization of transgenic maize harboring the Bacillus thuringiensis (Bt) cry1Ah gene by Bacillus subtilis strain B916-gfp present in plant tissues and soil. Bt and nontransgenic maize were inoculated with B916-gfp by seed soaking, or root irrigation under both laboratory greenhouse and field conditions. During the growing season, B916-gfp colonized transgenic as well as nontransgenic plants by both inoculation methods. No differences were observed in B916-gfp population size between transgenic and nontransgenic plants, except at one or two time points in the roots and stems that did not persist over the examination period. Furthermore, planting transgenic maize did not affect the number of B916-gfp in bulk soil in either laboratory or field trials. These results indicate that transgenic modification of maize with the cry1Ah gene has no influence on colonization by the endophytic bacteria B916-gfp present in the plant and in bulk soil. © 2016 The Authors. MicrobiologyOpenpublished by John Wiley & Sons Ltd.

  7. PERFORMANCE AND PERSISTENCE OF GREEN FLUORESCENT PROTEIN (gfp) MARKED AZOTOBACTER CHROOCOCCUM IN STERILIZED AND UNSTERILIZED WHEAT RHIZOSPHERIC SOIL

    Institute of Scientific and Technical Information of China (English)

    SINGH R; KUMAR V; SHARMA S; BEHL RK; SINGH BP; NARULA N

    2005-01-01

    The persistence and performance (growth promoting potential) of green fluorescent protein (gfp) marked Azotobacter chroococcum strain ABR 4G were studied in sterilized and unsterilized wheat rhizospheric soil. The gfp was integrated via Tn 5 transposition into A. chroococcum chromosome and the resultant gfp marked colonies were identified by green fluorescent emission under UV light. The gfp was stably maintained in A. chroococcum and the gfp insertion had no apparent adverse effect on the growth promoting properties of the marked soil isolate ABR 4G. The growth promoting properties ( nitrogen fixation, ammonia excretion, phosphate solubilization and IAA production) of the parent soil isolate and the gfp marked strain were found to be almost the same. All the quantitative wheat plant traits were significantly influenced by inoculation of A. chroococcum ABR 4G strain in sterilized and unsterilized soil. Inoculated bacterial counts increased gradually in wheat rhizosphere, reached maximum on 60th d and declined on 80th d. Fertility levels also affected survival of marked strain and the survival was comparable in sterilized and unsterilized soil. The growth promoting properties were also determined from the marked strain reisolated from wheat rhizosphere in both types of soil. Fig 1, Tab 2, Ref 22

  8. Identification and characterization of proteins involved in nuclear organization using Drosophila GFP protein trap lines.

    Directory of Open Access Journals (Sweden)

    Margaret Rohrbaugh

    Full Text Available BACKGROUND: Strains from a collection of Drosophila GFP protein trap lines express GFP in the normal tissues where the endogenous protein is present. This collection can be used to screen for proteins distributed in the nucleus in a non-uniform pattern. METHODOLOGY/PRINCIPAL FINDINGS: We analyzed four lines that show peripheral or punctate nuclear staining. One of these lines affects an uncharacterized gene named CG11138. The CG11138 protein shows a punctate distribution in the nuclear periphery similar to that of Drosophila insulator proteins but does not co-localize with known insulators. Interestingly, mutations in Lamin proteins result in alterations in CG11138 localization, suggesting that this protein may be a novel component of the nuclear lamina. A second line affects the Decondensation factor 31 (Df31 gene, which encodes a protein with a unique nuclear distribution that appears to segment the nucleus into four different compartments. The X-chromosome of males is confined to one of these compartments. We also find that Drosophila Nucleoplasmin (dNlp is present in regions of active transcription. Heat shock leads to loss of dNlp from previously transcribed regions of polytene chromosome without redistribution to the heat shock genes. Analysis of Stonewall (Stwl, a protein previously found to be necessary for the maintenance of germline stem cells, shows that Stwl is present in a punctate pattern in the nucleus that partially overlaps with that of known insulator proteins. Finally we show that Stwl, dNlp, and Df31 form part of a highly interactive network. The properties of other components of this network may help understand the role of these proteins in nuclear biology. CONCLUSIONS/SIGNIFICANCE: These results establish screening of GFP protein trap alleles as a strategy to identify factors with novel cellular functions. Information gained from the analysis of CG11138 Stwl, dNlp, and Df31 sets the stage for future studies of these

  9. Construction of new GFP-tagged fusants for Trichoderma harzianum with enhanced biocontrol activity

    Directory of Open Access Journals (Sweden)

    Kowsari Mojegan

    2014-07-01

    Full Text Available Trichoderma is one of the most exploited biocontrol agents for the management of plant diseases. In biocontrol ecology, the critical factors are detection, and the monitoring and recovery of specific biocontrol agents either naturally present or deliberately released into the environment. Protoplast fusion is an appropriate tool for the improvement of biocontrol Trichoderma strains. Protoplast isolation from Trichoderma harzianum was achieved using 24 h culture age, 6.6 mg/ml Novazym L 1412 at 30°C which resulted the maximum protoplast yield of 5 × 108/ml. The self-fused protoplasts were regenerated and 12 fusants were selected based on their growth rate on 2% colloidal chitin medium. Next, a comparison was done for chitinase and antagonistic activity. Transcriptomic analysis based on quantitative real-time RT-PCR, demonstrated that T8-05 fusant expressed 1.5 fold of chit42 transcript as compared with the parental line. This fusant with 7.02±0.15U chitinase activity showed a higher growth inhibition rate (100% than the parent strain, against Rhizoctonia solani. To obtain a genetically marked fusant that can be used as a biomonitor, the fusant was cotransformed with the gfp and amdS genes. The morphology and viability of selected cotransformant (FT8-7MK-05-2 was similar to the parent. Green fluorescing conidia were observed within the first 2 days of incubation in the soil, and this was followed by the formation of chlamydopores after 60 days. The colonisation of the gfp-tagged fusant was also monitored visually on R. solani sclerotia by scanning electron microscopy. Production of gfp-tagged fusant of Trichoderma spp. provides a potentially useful tool for monitoring hyphal growth patterns and the population of biocontrol agent isolates introduced into environmental systems.

  10. Analysis of computational models for an accurate study of electronic excitations in GFP

    DEFF Research Database (Denmark)

    Schwabe, Tobias; Beerepoot, Maarten; Olsen, Jógvan Magnus Haugaard

    2015-01-01

    Using the chromophore of the green fluorescent protein (GFP), the performance of a hybrid RI-CC2 / polarizable embedding (PE) model is tested against a quantum chemical cluster pproach. Moreover, the effect of the rest of the protein environment is studied by systematically increasing the size...... that the treatment of only a small region around the chromophore is only by coincidence a good approximation. Therefore, such cluster approaches should be used with care. Based on our results, we suggest that polarizable embedding models, including a large part of the environment to describe its effect...

  11. Impact of copy number of distinct SV40PolyA segments on expression of a GFP reporter gene

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The presence of Alu repeats downregulates the expression of the green fluorescent protein(GFP) gene.We found that SV40PolyA(PolyA,240 bp),in either orientation,eliminated the inhibition of GFP gene expression induced by Alu repeats when it was placed between the GFP gene and the Alu repeats.In this study,4 different segments(each 60 bp) were amplified from antisense PolyA(PolyAas) by PCR,and inserted upstream of Alu14 in pAlu14 plasmid(14 Alu repeats inserted downstream of the GFP gene in vector pEGFP-C1 in a head-tail tandem manner).Segments 1F1R(the first 60 bp segment at the 5’ end of PolyAas) and 4F4R(the fourth 60 bp segment from the 5’ end of PolyAas) did not activate GFP gene expression,whereas 2F2R and 3F3R(the middle two segments) did(as detected by Northern blot analysis and fluorescent microscopy).Different copy numbers of 2F2R and 3F3R segments,in a head and tail tandem manner,were inserted downstream of the GFP gene in pAlu14.p2F2R*4-Alu28,p3F3R*4-Alu18 and p3F3R*4-Alu28 were used as length controls to verify that the decrease in the expression of GFP was not due to the increased length of the inserted segment in the expression vectors.We found that 2 and 4 copies of 2F2R or 3F3R activated the GFP gene more strongly than one copy of them.However,more than 8 copies of 2F2R or 3F3R reduced the activation of the GFP gene.We concluded that SV40PolyAas contained at least two gene-activating elements(2F2R and 3F3R) and 2-4 copies of 2F2R or 3F3R were optimal for the expression of the GFP gene.

  12. Illuminating the Sites of Enterovirus Replication in Living Cells by Using a Split-GFP-Tagged Viral Protein.

    Science.gov (United States)

    van der Schaar, H M; Melia, C E; van Bruggen, J A C; Strating, J R P M; van Geenen, M E D; Koster, A J; Bárcena, M; van Kuppeveld, F J M

    2016-01-01

    Like all other positive-strand RNA viruses, enteroviruses generate new organelles (replication organelles [ROs]) with a unique protein and lipid composition on which they multiply their viral genome. Suitable tools for live-cell imaging of enterovirus ROs are currently unavailable, as recombinant enteroviruses that carry genes that encode RO-anchored viral proteins tagged with fluorescent reporters have not been reported thus far. To overcome this limitation, we used a split green fluorescent protein (split-GFP) system, comprising a large fragment [strands 1 to 10; GFP(S1-10)] and a small fragment [strand 11; GFP(S11)] of only 16 residues. The GFP(S11) (GFP with S11 fragment) fragment was inserted into the 3A protein of the enterovirus coxsackievirus B3 (CVB3), while the large fragment was supplied by transient or stable expression in cells. The introduction of GFP(S11) did not affect the known functions of 3A when expressed in isolation. Using correlative light electron microscopy (CLEM), we showed that GFP fluorescence was detected at ROs, whose morphologies are essentially identical to those previously observed for wild-type CVB3, indicating that GFP(S11)-tagged 3A proteins assemble with GFP(S1-10) to form GFP for illumination of bona fide ROs. It is well established that enterovirus infection leads to Golgi disintegration. Through live-cell imaging of infected cells expressing an mCherry-tagged Golgi marker, we monitored RO development and revealed the dynamics of Golgi disassembly in real time. Having demonstrated the suitability of this virus for imaging ROs, we constructed a CVB3 encoding GFP(S1-10) and GFP(S11)-tagged 3A to bypass the need to express GFP(S1-10) prior to infection. These tools will have multiple applications in future studies on the origin, location, and function of enterovirus ROs. IMPORTANCE Enteroviruses induce the formation of membranous structures (replication organelles [ROs]) with a unique protein and lipid composition specialized for

  13. A new GFP-tagged line reveals unexpected Otx2 protein localization in retinal photoreceptors

    Directory of Open Access Journals (Sweden)

    Godement Pierre

    2007-11-01

    Full Text Available Abstract Background Dynamic monitoring of protein expression and localization is fundamental to the understanding of biological processes. The paired-class homeodomain-containing transcription factor Otx2 is essential for normal head and brain development in vertebrates. Recent conditional knockout studies have pointed to multiple roles of this protein during late development and post-natal life. Yet, later expression and functions remain poorly characterized as specific reagents to detect the protein at any stage of development are still missing. Results We generated a new mouse line harbouring an insertion of the GFP gene within the Otx2 coding sequence to monitor the gene activity while preserving most of its functions. Our results demonstrate that this line represents a convenient tool to capture the dynamics of Otx2 gene expression from early embryonic stages to adulthood. In addition, we could visualize the intracellular location of Otx2 protein. In the retina, we reinterpret the former view of protein distribution and show a further level of regulation of intranuclear protein localization, which depends on the cell type. Conclusion The GFP-tagged Otx2 mouse line fully recapitulates previously known expression patterns and brings additional accuracy and easiness of detection of Otx2 gene activity. This opens up the way to live imaging of a highly dynamic actor of brain development and can be adapted to any mutant background to probe for genetic interaction between Otx2 and the mutated gene.

  14. Establishment of cells to monitor Microprocessor through fusion genes of microRNA and GFP.

    Science.gov (United States)

    Tsutsui, Motomu; Hasegawa, Hitoki; Adachi, Koichi; Miyata, Maiko; Huang, Peng; Ishiguro, Naoki; Hamaguchi, Michinari; Iwamoto, Takashi

    2008-08-08

    Microprocessor, the complex of Drosha and DGCR8, promotes the processing of primary microRNA to precursor microRNA, which is a crucial step for microRNA maturation. So far, no convenient assay systems have been developed for observing this step in vivo. Here we report the establishment of highly sensitive cellular systems where we can visually monitor the function of Microprocessor. During a series of screening of transfectants with fusion genes of the EGFP cDNA and primary microRNA genes, we have obtained certain cell lines where introduction of siRNA against DGCR8 or Drosha strikingly augments GFP signals. In contrast, these cells have not responded to Dicer siRNA; thus they have a unique character that GFP signals should be negatively and specifically correlated to the action of Microprocessor among biogenesis of microRNA. These cell lines can be useful tools for real-time analysis of Microprocessor action in vivo and identifying its novel modulators.

  15. Properties of baculovirus particles displaying GFP analyzed by fluorescence correlation spectroscopy.

    Science.gov (United States)

    Toivola, Jouni; Ojala, Kirsi; Michel, Patrik O; Vuento, Matti; Oker-Blom, Christian

    2002-12-01

    Recombinant baculovirus particles displaying green fluorescent protein (GFP) fused to the major envelope glycoprotein gp64 of the Autographa californica multicapsid nucleopolyhedrovirus (AcMNPV) were characterized by fluorescence correlation spectroscopy (FCS). FCS detected Brownian motion of single, intact recombinant baculovirus display particles with a diffusion coefficient (D) of (2.89 +/- 0.74) x 10(-8) cm2s(-1) and an apparent hydrodynamic radius of 83.35 +/- 21.22 nm. In the presence of sodium dodecyl sulfate (SDS), Triton X-100, and octylglucoside, the diffusion time was reduced to the 0.2 ms range (D = 7.57 x 10(-7) cm2s(-1)), showing that the fusion proteins were anchored in the viral envelope. This allowed for a calculation of the number of single gp64 fusion proteins incorporated in the viral membrane. A mean value of 3.2 fluorescent proteins per virus particle was obtained. Our results show that FCS is the method of choice for studying enveloped viruses such as a display virus with one component being GFP.

  16. Colonization and movement of GFP-labeled Clavibacter michiganensis subsp. michiganensis during tomato infection.

    Science.gov (United States)

    Chalupowicz, L; Zellermann, E-M; Fluegel, M; Dror, O; Eichenlaub, R; Gartemann, K-H; Savidor, A; Sessa, G; Iraki, N; Barash, I; Manulis-Sasson, S

    2012-01-01

    The vascular pathogen Clavibacter michiganensis subsp. michiganensis is responsible for bacterial wilt and canker of tomato. Pathogenicity of this bacterium is dependent on plasmid-borne virulence factors and serine proteases located on the chromosomal chp/tomA pathogenicity island (PAI). In this study, colonization patterns and movement of C. michiganensis subsp. michiganensis during tomato infection was examined using a green fluorescent protein (GFP)-labeled strain. A plasmid expressing GFP in C. michiganensis subsp. michiganensis was constructed and found to be stable in planta for at least 1 month. Confocal laser-scanning microscopy (CLSM) of inoculated stems showed that the pathogen extensively colonizes the lumen of xylem vessels and preferentially attaches to spiral secondary wall thickening of the protoxylem. Acropetal movement of the wild-type strain C. michiganensis subsp. michiganensis NCPPB382 (Cmm382) in tomato resulted in an extensive systemic colonization of the whole plant reaching the apical region after 15 days, whereas Cmm100 (lacking the plasmids pCM1 and pCM2) or Cmm27 (lacking the chp/tomA PAI) remained confined to the area surrounding of the inoculation site. Cmm382 formed biofilm-like structures composed of large bacterial aggregates on the interior of xylem walls as observed by CLSM and scanning electron microscopy. These findings suggest that virulence factors located on the chp/tomA PAI or the plasmids are required for effective movement of the pathogen in tomato and for the formation of cellular aggregates.

  17. In Vivo GFP Knockdown by Cationic Nanogel-siRNA Polyplexes

    Directory of Open Access Journals (Sweden)

    Arun R. Shrivats

    2015-07-01

    Full Text Available RNA interference (RNAi is a powerful tool to treat diseases and elucidate target gene function. Prior to clinical implementation, however, challenges including the safe, efficient and targeted delivery of siRNA must be addressed. Here, we report cationic nanogel nanostructured polymers (NSPs prepared by atom transfer radical polymerization (ATRP for in vitro and in vivo siRNA delivery in mammalian models. Outcomes from siRNA protection studies suggested that nanogel NSPs reduce enzymatic degradation of siRNA within polyplexes. Further, the methylation of siRNA may enhance nuclease resistance without compromising gene knockdown potency. NSP-mediated RNAi treatments against Gapdh significantly reduced GAPDH enzyme activity in mammalian cell culture models supplemented with 10% serum. Moreover, nanogel NSP-mediated siRNA delivery significantly inhibited in vivo GFP expression in a mouse model. GFP knockdown was siRNA sequence-dependent and facilitated by nanogel NSP carriers. Continued testing of NSP/siRNA compositions in disease models may produce important new therapeutic options for patient care.

  18. A GFP trap study uncovers the functions of Gilgamesh protein kinase in Drosophila melanogaster spermatogenesis.

    Science.gov (United States)

    Nerusheva, O O; Dorogova, N V; Gubanova, N V; Yudina, O S; Omelyanchuk, L V

    2009-05-01

    The function of the gene gilgamesh (89B9-12) encoding a casein kinase in Drosophila spermatogenesis was studied. The chimeric Gilgamesh-GFP protein in spermatocytes is cortically located. In the polar and apolar spermatocytes, it concentrates at the terminal ends of the fusome, the organelle that passes through the system of ring canals of the spermatocyte cyst. At the stage of spermatid elongation, the protein associates with the nucleus. A spot of the highest Gilgamesh-GFP concentration in the nucleus co-localizes with gamma-tubulin in the basal body. At later stages, Gilgamesh is localized to the individualization complex (IC), leaving the nuclei somewhat before the IC investment cones, as detected by actin binding. The sterile mutation due to the gilgamesh gene leads to the phenotype of scattered nuclei and altered structure of actin cones in the individualizing spermatid cyst. Ultrastructural evidence confirmed defective spermatid individualization due to the mutation. The phylogenetic origin of the protein, and the connection between vesicular trafficking and spermatid individualization, are discussed.

  19. Production of transgenic chickens expressing a tetracycline-inducible GFP gene.

    Science.gov (United States)

    Kwon, Mo Sun; Koo, Bon Chul; Roh, Ji Yeol; Kim, Minjee; Kim, Jin-Hoi; Kim, Teoan

    2011-07-15

    There is much interest in using farm animals as 'bioreactors' to produce large quantities of biopharmaceuticals. However, uncontrolled constitutive expression of foreign genes have been known to cause serious physiological disturbances in transgenic animals. The objective of this study was to test the feasibility of the controllable expression of an exogenous gene in the chicken. A retrovirus vector was designed to express GFP (green fluorescent protein) and rtTA (reverse tetracycline-controlled transactivator) under the control of the tetracycline-inducible promoter and the PGK (phosphoglycerate kinase) promoter, respectively. G0 founder chickens were produced by infecting the blastoderm of freshly laid eggs with concentrated retrovirus vector. Feeding the chickens obtained with doxycycline, a tetracycline derivative, resulted in emission of green body color under fluorescent light, and no apparent significant physiological dysfunctions. Successful germline transmission of the exogenous gene was also confirmed. Expression of the GFP gene reverted to the pre-induction levels when doxycycline was removed from the diet. The results showed that a tetracycline-inducible expression system in transgenic animals might be a promising solution to minimize physiological disturbances caused by the transgene. Copyright © 2011 Elsevier Inc. All rights reserved.

  20. Cloning, expression, purification, and characterization of LC-1 ScFv with GFP tag

    Institute of Scientific and Technical Information of China (English)

    LU Min; GONG Xing-guo; YU Hong; LI Jian-yong

    2005-01-01

    Total RNA was isolated from the hybridoma cell line (LC-1), which secretes anti-lung adenocarcinoma monoclonal antibody, and was transferred into cDNA. Based on the FR1 (framework region 1) and FR4 conserved regions of LC-I gene, the variable regions of heavy chain (Vh) and light chain (Vl) were amplified, and the Vh and modified Vl were connected to single chain Fv (ScFv) by SOE-PCR (splice overlap extension PCR). The modified ScFv was fused with green fluorescent protein (GFP)and introduced into E. coli JMi09. The fusion protein induced by IPTG (Isopropylthiogalactoside) was about 57000 on a 10%SDS-PAGE gel (10% Sds Polyacrylamide Gel Electrophoresis), and primarily manifested as inclusion bodies. The renatured protein purified by Ni-NTA Superflow resins showed ability to bind to antigen on SPC-A-1 lung adenocarcinoma. In addition, the induced host cells fluoresced bright green under 395 nm wavelength, which indicated that the expected protein with dual activity was expressed in the prokaryotic system. The ScFv with GFP tag used in this research can be applied as a new reagent to detect immunological dye, and provide a feasible way to detect adenocarcinoma in a clinical setting.

  1. Migration and Differentiation of GFP-transplanted Bone Marrow-derived Cells into Experimentally Induced Periodontal Polyp in Mice.

    Science.gov (United States)

    Matsuda, Saeka; Shoumura, Masahito; Osuga, Naoto; Tsujigiwa, Hidetsugu; Nakano, Keisuke; Okafuji, Norimasa; Ochiai, Takanaga; Hasegawa, Hiromasa; Kawakami, Toshiyuki

    2016-01-01

    Perforation of floor of the dental pulp is often encountered during root canal treatment in routine clinical practice of dental caries. If perforation were large, granulation tissue would grow to form periodontal polyp. Granulation tissue consists of proliferating cells however their origin is not clear. It was shown that the cells in granulation tissue are mainly from migration of undifferentiated mesenchymal cells of the bone marrow. Hence, this study utilized GFP bone marrow transplantation mouse model. The floor of the pulp chamber in maxillary first molar was perforated using ½ dental round bur. Morphological assessment was carried out by micro CT and microscopy and GFP cell mechanism was further assessed by immunohistochemistry using double fluorescent staining with GFP-S100A4; GFP-Runx2 and GFP-CD31. Results of micro CT revealed alveolar bone resorption and widening of periodontal ligament. Histopathological examination showed proliferation of fibroblasts with some round cells and blood vessels in the granulation tissue. At 2 weeks, the outermost layer of the granulation tissue was lined by squamous cells with distinct intercellular bridges. At 4 weeks, the granulation tissue became larger than the perforation and the outermost layer was lined by relatively typical stratified squamous epithelium. Double immunofluorescent staining of GFP and Runx2 revealed that both proteins were expressed in spindle-shaped cells. Double immunofluorescent staining of GFP and CD31 revealed that both proteins were expressed in vascular endothelial cells in morphologically distinct vessels. The results suggest that fibroblasts, periodontal ligament fibroblasts and blood vessels in granulation tissue were derived from transplanted-bone marrow cells. Thus, essential growth of granulation tissue in periodontal polyp was caused by the migration of undifferentiated mesenchymal cells derived from bone marrow, which differentiated into fibroblasts and later on differentiated into

  2. Correlative and integrated light and electron microscopy of in-resin GFP fluorescence, used to localise diacylglycerol in mammalian cells

    Energy Technology Data Exchange (ETDEWEB)

    Peddie, Christopher J.; Blight, Ken; Wilson, Emma [Electron Microscopy Unit, London Research Institute, Cancer Research UK, London WC2A 3LY (United Kingdom); Melia, Charlotte [Electron Microscopy Unit, London Research Institute, Cancer Research UK, London WC2A 3LY (United Kingdom); Cell Biophysics Laboratory, London Research Institute, Cancer Research UK, London WC2A 3LY (United Kingdom); Department of Molecular Cell Biology, Leiden University Medical Centre, 2300 RC Leiden (Netherlands); Marrison, Jo [Department of Biology, The University of York, Heslington, York (United Kingdom); Carzaniga, Raffaella [Electron Microscopy Unit, London Research Institute, Cancer Research UK, London WC2A 3LY (United Kingdom); Domart, Marie-Charlotte [Electron Microscopy Unit, London Research Institute, Cancer Research UK, London WC2A 3LY (United Kingdom); Cell Biophysics Laboratory, London Research Institute, Cancer Research UK, London WC2A 3LY (United Kingdom); O' Toole, Peter [Department of Biology, The University of York, Heslington, York (United Kingdom); Larijani, Banafshe [Cell Biophysics Laboratory, London Research Institute, Cancer Research UK, London WC2A 3LY (United Kingdom); Cell Biophysics Laboratory, Unidad de Biofísica (CSIC-UPV/EHU),Sarriena s/n, 48940 Leioa (Spain); IKERBASQUE, Basque Foundation for Science, Bilbao (Spain); Collinson, Lucy M. [Electron Microscopy Unit, London Research Institute, Cancer Research UK, London WC2A 3LY (United Kingdom)

    2014-08-01

    Fluorescence microscopy of GFP-tagged proteins is a fundamental tool in cell biology, but without seeing the structure of the surrounding cellular space, functional information can be lost. Here we present a protocol that preserves GFP and mCherry fluorescence in mammalian cells embedded in resin with electron contrast to reveal cellular ultrastructure. Ultrathin in-resin fluorescence (IRF) sections were imaged simultaneously for fluorescence and electron signals in an integrated light and scanning electron microscope. We show, for the first time, that GFP is stable and active in resin sections in vacuo. We applied our protocol to study the subcellular localisation of diacylglycerol (DAG), a modulator of membrane morphology and membrane dynamics in nuclear envelope assembly. We show that DAG is localised to the nuclear envelope, nucleoplasmic reticulum and curved tips of the Golgi apparatus. With these developments, we demonstrate that integrated imaging is maturing into a powerful tool for accurate molecular localisation to structure. - Highlights: • GFP and mCherry fluorescence are preserved in heavy-metal stained mammalian cells embedded in resin • Fluorophores are stable and intensity is sufficient for detection in ultrathin sections • Overlay of separate LM and EM images from the same ultrathin section improves CLEM protein localisation precision • GFP is stable and active in the vacuum of an integrated light and scanning EM • Integrated light and electron microscopy shows new subcellular locations of the lipid diacylglycerol.

  3. Tissue-specific expression of GFP reporter gene in germline driven by GATA-2 promoter and enhancers in zebrafish

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    GATA-2,a transcription factor,is expressed in several types of blood cells and in the central nervous system (CNS),and regulates the differentiation of these cells.We have obtained five zebrafish transgenic germlines that carry and express the green fluorescent protein (GFP) gene ligated to various 5′flanking sequences of zebrafish GATA-2 gene.The spatial pattern of GFP expression varies,mainly depending on which regulatory sequence is used,among the germlines.In some of the germlines,the expression of GFP is restricted to the CNS and the enveloping layer (EVL) cells,while in some other lines GFP is observed only in the CNS.It is noted that the intensity of GFP in the transgenic fish remain unchanged after a six-generation passage of the transgenes.The transgenic fish could find its uses in the future in generating tissue-specific,even cellspecific mutant fish and in functional study of related genes through transgenesis.

  4. Establishment of a preadipocyte cell line derived from mature adipocytes of GFP transgenic mice and formation of adipose tissue.

    Science.gov (United States)

    Nobusue, Hiroyuki; Endo, Tsuyoshi; Kano, Koichiro

    2008-06-01

    We established a preadipocyte cell line from mature adipocytes obtained from subcutaneous fat tissue of green fluorescent protein (GFP) transgenic mice. The floating top layer, containing mature adipocytes, was isolated from subcutaneous fat tissue by collagenase digestion and filtration. Fluorescence-activated cell sorting and microscopic analysis revealed that the floating cell fraction comprised a highly homogeneous adipocyte population with no adipose stromal-vascular cells. Isolated mature adipocytes dedifferentiated into fibroblast-like cells and actively proliferated in ceiling culture. In vitro studies showed that the cells could redifferentiate into mature adipocytes in an identical way to 3T3-L1 preadipocytes. No changes in the differentiation pattern were observed during the propagation of our cells. They were successfully maintained and differentiated for at least 22 passages. We named these cells dedifferentiated fat (DFAT-GFP) cells. When DFAT-GFP cells were implanted subcutaneously into C57BL/6N mice, they developed highly vascularized fat pads that morphologically resembled normal subcutaneous adipose tissue and consisted of GFP-positive cells; however, implanted 3T3-L1 cells did not have such an effect on the mice. We conclude that DFAT-GFP cells provide a model that should enable us to study the mechanisms of adipocyte differentiation and adipose tissue formation in vivo and in vitro.

  5. Fluorescent Leishmania species: development of stable GFP expression and its application for in vitro and in vivo studies.

    Science.gov (United States)

    Bolhassani, Azam; Taheri, Tahereh; Taslimi, Yasaman; Zamanilui, Soheila; Zahedifard, Farnaz; Seyed, Negar; Torkashvand, Fatemeh; Vaziri, Behrouz; Rafati, Sima

    2011-03-01

    Reporter genes have proved to be an excellent tool for studying disease progression. Recently, the green fluorescent protein (GFP) ability to quantitatively monitor gene expression has been demonstrated in different organisms. This report describes the use of Leishmania tarentolae (L. tarentolae) expression system (LEXSY) for high and stable levels of GFP production in different Leishmania species including L. tarentolae, L. major and L. infantum. The DNA expression cassette (pLEXSY-EGFP) was integrated into the chromosomal ssu locus of Leishmania strains through homologous recombination. Fluorescent microscopic image showed that GFP transgenes can be abundantly and stably expressed in promastigote and amastigote stages of parasites. Furthermore, flow cytometry analysis indicated a clear quantitative distinction between wild type and transgenic Leishmania strains at both promastigote and amastigote forms. Our data showed that the footpad lesions with GFP-transfected L. major are progressive over time by using fluorescence small-animal imaging system. Consequently, the utilization of stable GFP-transfected Leishmania species will be appropriate for in vitro and in vivo screening of anti-leishmanial drugs and vaccine development as well as understanding the biology of the host-parasite interactions at the cellular level.

  6. Development and characterization of a clinical strain of Coxsackievirus A16 and an eGFP infectious clone

    Institute of Scientific and Technical Information of China (English)

    Chenglin; Deng; Xiaodan; Li; Siqing; Liu; Linlin; Xu; Hanqing; Ye; Cheng-Feng; Qin; Bo; Zhang

    2015-01-01

    Coxsackievirus A16(CA16) is one of the major causes of hand, foot, and mouth disease(HFMD) worldwide, which is a common illness that affects children. The frequent occurrence of HFMD outbreaks has become a serious public health problem in Asia. Therefore, it is important to understand the pathogenesis and replication of CA16. In this study, a stable infectious c DNA clone of an epidemic strain of Coxsackievirus A16(CA16) was assembled, and subsequently a reporter virus(e GFP-CA16) was constructed by inserting the e GFP gene between the 5’-UTR and the N-terminus of VP4, with the addition of a 2A protease cleavage site(ITTLG) at its C-terminus. This was transfected into Vero cells to generate infectious recombinant viruses. The growth characteristics and plaque morphology, in vitro, in mammalian cells were found to be indistinguishable between the parental and recombinant viruses. Although the e GFP-CA16 showed smaller plaque size as compared to recombinant CA16, both were found to exhibit similar growth trends and EC50 of NITD008. In summary, this stable infectious c DNA clone should provide a valuable experimental system to study CA16 infection and host response. The e GFP-CA16 is expected to provide a powerful tool to monitor e GFP expression in infected cells and to evaluate the antiviral activity of potential antiviral agents in the treatment of CA16 infections.

  7. EXPRESSION IN VIVO DU GÈNE GFP SOUS LA FORME D’UNE PROTÉINE DE FUSION

    Directory of Open Access Journals (Sweden)

    Lucian Negura

    2006-08-01

    Full Text Available La protéine GFP (Green Fluorescent Protein se caractérise par sa capacité à émettre sous l’action des rayons UV une lumière verte de basse énergie, ce qui la rend particulièrement utile en biotechnologies. Nous avons procédé à la production de la GFP in vivo par Eschericha coli sous forme d’une protéine chimère de fusion avec le peptide de la –Galactosidase. Pour ce, nous avons cloné un fragment d’ADN comportant la phase codante de la GFP à partir d’un vecteur dans lequel il ne peut être exprimé vers un autre vecteur permettant lui cette expression.

  8. Assessment of GFP fluorescence in cells of Streptococcus gordonii under conditions of low pH and low oxygen concentration

    DEFF Research Database (Denmark)

    Hansen, M.C.; Palmer, R.J.; Udsen, C.

    2001-01-01

    . A lower limit of oxygen concentration for maturation of the GFP fluorophore was determined: fluorescence was emitted at 0.1 p.p.m. dissolved oxygen (in conventionally prepared anaerobic media lacking reducing agents), whereas no fluorescence was detected in the presence of 0.025 p.p.m. dissolved oxygen......Use of green fluorescent protein (GFP) as a molecular reporter is restricted by several environmental factors, such as its requirement for oxygen in the development of the fluorophore, and its poor fluorescence at low pH. There are conflicting data on these limitations, however, and systematic...... (lateral or vertical) within the >50 mum thick biofilm, and fluorescence development after the shift to aerobic conditions occurred throughout the biofilm (even at the substratum). This suggests that oxygen gradients, which might result in reduced GFP fluorescence, did not exist in the >50 mum thick...

  9. Dose-dependent fate of GFP-expressing Escherichia coli in the alimentary canal of adult house flies.

    Science.gov (United States)

    Kumar, N H V; Nayduch, D

    2016-06-01

    The adult house fly Musca domestica (L.) (Diptera: Muscidae) can disseminate bacteria from microbe-rich substrates to areas in which humans and domesticated animals reside. Because bacterial abundance fluctuates widely across substrates, flies encounter and ingest varying amounts of bacteria. This study investigated the dose-dependent survival of bacteria in house flies. Flies were fed four different 'doses' of green fluorescent protein (GFP)-expressing Escherichia coli (GFP E. coli) (very low, low, medium, high) and survival was determined at 1, 4, 10 and 22 h post-ingestion by culture and epifluorescent microscopy. Over 22 h, the decline in GFP E. coli was significant in all treatments (P house flies, may exist and is likely to be immune-mediated. Understanding dose-dependent bacterial survival in flies can help in predicting bacteria transmission potential.

  10. Transplantation of GFP-expressing blastomeres for live imaging of retinal and brain development in chimeric zebrafish embryos.

    Science.gov (United States)

    Zou, Jian; Wei, Xiangyun

    2010-07-19

    Cells change extensively in their locations and property during embryogenesis. These changes are regulated by the interactions between the cells and their environment. Chimeric embryos, which are composed of cells of different genetic background, are great tools to study the cell-cell interactions mediated by genes of interest. The embryonic transparency of zebrafish at early developmental stages permits direct visualization of the morphogenesis of tissues and organs at the cellular level. Here, we demonstrate a protocol to generate chimeric retinas and brains in zebrafish embryos and to perform live imaging of the donor cells. The protocol covers the preparation of transplantation needles, the transplantation of GFP-expressing donor blastomeres to GFP-negative hosts, and the examination of donor cell behavior under live confocal microscopy. With slight modifications, this protocol can also be used to study the embryonic development of other tissues and organs in zebrafish. The advantages of using GFP to label donor cells are also discussed.

  11. Genetic transformation with the gfp gene of Colletotrichum gloeosporioides isolates from coffee with blister spot.

    Science.gov (United States)

    Armesto, Cecilia; Maia, Fernanda Gonçalves Martins; de Abreu, Mário Sobral; Figueira, Antonia Dos Reis; da Silva, Bruno Marques; Monteiro, Fernando Pereira

    2012-07-01

    Blister spot (Colletotrichum gloeosporioides) is now widespread in most coffee producing states of Brazil, becoming a limiting factor for production. The lack of data relating to the reproduction of typical symptoms (light green, oily patches) leaves a gap within the pathosystem, forcing the search for new methodologies for monitoring the disease. Monitoring of genetically modified organisms has proven to be an effective tool in understanding the host × pathogen interactions. Thus, the present study was carried out to evaluate the effectiveness of two systems of genetic transformation in obtaining mutants using the gfp reporter gene. Using the two transformation systems (PEG and electroporation) revealed the efficiency of both, confirmed by fluorescence microscopy and resistance to the antibiotic hygromycin-B, when incorporated into the culture medium. The fungus maintained its cultural and morphological characteristics when compared to wild strains. When inoculated on coffee seedlings, it was found that the pathogenicity of the processed isolates had not changed.

  12. Genetic transformation with the gfp gene of Colletotrichum gloeosporioides isolates from coffee with blister spot

    Directory of Open Access Journals (Sweden)

    Cecilia Armesto

    2012-09-01

    Full Text Available Blister spot (Colletotrichum gloeosporioides is now widespread in most coffee producing states of Brazil, becoming a limiting factor for production. The lack of data relating to the reproduction of typical symptoms (light green, oily patches leaves a gap within the pathosystem, forcing the search for new methodologies for monitoring the disease. Monitoring of genetically modified organisms has proven to be an effective tool in understanding the host x pathogen interactions. Thus, the present study was carried out to evaluate the effectiveness of two systems of genetic transformation in obtaining mutants using the gfp reporter gene. Using the two transformation systems (PEG and electroporation revealed the efficiency of both, confirmed by fluorescence microscopy and resistance to the antibiotic hygromycin-B, when incorporated into the culture medium. The fungus maintained its cultural and morphological characteristics when compared to wild strains. When inoculated on coffee seedlings, it was found that the pathogenicity of the processed isolates had not changed.

  13. Impact of carbondiimide crosslinker used for magnetic carbon nanotube mediated GFP plasmid delivery

    Energy Technology Data Exchange (ETDEWEB)

    Hao Yuzhi; He Chuan; Yang Xiaoyan; Huang Min; Chen Jie [Department of Electrical and Computer Engineering, University of Alberta, Edmonton, AB (Canada); Xu Peng [National Institute of Nanotechnology, Edmonton, AB (Canada); Xing, James [IntelligentNano Incorporated, Edmonton, AB (Canada)

    2011-07-15

    1-ethyl-3-(3-dimethylaminopropyl) carbondiimide hydrochloride (EDC) is commonly used as a crosslinker to help bind biomolecules, such as DNA plasmids, with nanostructures. However, EDC often remains, after a crosslink reaction, in the micro-aperture of the nanostructure, e.g., carbon nanotube. The remaining EDC shows positive green fluorescent signals and makes a nanostructure with a strong cytotoxicity which induces cell death. The toxicity of EDC was confirmed on a breast cancer cell line (MCF-7) and two leukemic cell lines (THP-1 and KG-1). The MCF-7 cells mainly underwent necrosis after treatment with EDC, which was verified by fluorescein isothiocyanate (FITC) annexin V staining, video microscopy and scanning electronic microscopy (SEM). If the EDC was not removed completely, the nanostructures with remaining EDC produced a green fluorescent background that could interfere with flow cytometry (FACS) measurement and result in false information about GFP plasmid delivery. Effective methods to remove residual EDC on macromolecules were also developed.

  14. Dual Fluorescence in GFP Chromophore Analogues: Chemical Modulation of Charge Transfer and Proton Transfer Bands.

    Science.gov (United States)

    Chatterjee, Tanmay; Mandal, Mrinal; Das, Ananya; Bhattacharyya, Kalishankar; Datta, Ayan; Mandal, Prasun K

    2016-04-14

    Dual fluorescence of GFP chromophore analogues has been observed for the first time. OHIM (o-hydroxy imidazolidinone) shows only a charge transfer (CT) band, CHBDI (p-cyclicamino o-hydroxy benzimidazolidinone) shows a comparable intensity CT and PT (proton transfer) band, and MHBDI (p-methoxy o-hydroxy benzimidazolidinone) shows a higher intensity PT band. It could be shown that the differential optical behavior is not due to conformational variation in the solid or solution phase. Rather, control of the excited state electronic energy level and excited state acidity constant by functional group modification could be shown to be responsible for the differential optical behavior. Chemical modification-induced electronic control over the relative intensity of the charge transfer and proton transfer bands could thus be evidenced. Support from single-crystal X-ray structure, NMR, femtosecond to nanosecond fluorescence decay analysis, and TDDFT-based calculation provided important information and thus helped us understand the photophysics better.

  15. Versatile microsphere attachment of GFP-labeled motors and other tagged proteins with preserved functionality

    Directory of Open Access Journals (Sweden)

    Michael Bugiel

    2015-11-01

    Full Text Available Microspheres are often used as handles for protein purification or force spectroscopy. For example, optical tweezers apply forces on trapped particles to which motor proteins are attached. However, even though many attachment strategies exist, procedures are often limited to a particular biomolecule and prone to non-specific protein or surface attachment. Such interactions may lead to loss of protein functionality or microsphere clustering. Here, we describe a versatile coupling procedure for GFP-tagged proteins via a polyethylene glycol linker preserving the functionality of the coupled proteins. The procedure combines well-established protocols, is highly reproducible, reliable, and can be used for a large variety of proteins. The coupling is efficient and can be tuned to the desired microsphere-to-protein ratio. Moreover, microspheres hardly cluster or adhere to surfaces. Furthermore, the procedure can be adapted to different tags providing flexibility and a promising attachment strategy for any tagged protein.

  16. Peculiarities of the Super-Folder GFP Folding in a Crowded Milieu

    Directory of Open Access Journals (Sweden)

    Olesya V. Stepanenko

    2016-10-01

    Full Text Available The natural cellular milieu is crowded by large quantities of various biological macromolecules. This complex environment is characterized by a limited amount of unoccupied space, limited amounts of free water, and changed solvent properties. Obviously, such a tightly packed cellular environment is poorly mimicked by traditional physiological conditions, where low concentrations of a protein of interest are analyzed in slightly salted aqueous solutions. An alternative is given by the use of a model crowded milieu, where a protein of interest is immersed in a solution containing high concentrations of various polymers that serve as model crowding agents. An expected outcome of the presence of such macromolecular crowding agents is their ability to increase conformational stability of a globular protein due to the excluded volume effects. In line with this hypothesis, the behavior of a query protein should be affected by the hydrodynamic size and concentration of an inert crowder (i.e., an agent that does not interact with the protein, whereas the chemical nature of a macromolecular crowder should not play a role in its ability to modulate conformational properties. In this study, the effects of different crowding agents (polyethylene glycols (PEGs of various molecular masses (PEG-600, PEG-8000, and PEG-12000, Dextran-70, and Ficoll-70 on the spectral properties and unfolding–refolding processes of the super-folder green fluorescent protein (sfGFP were investigated. sfGFP is differently affected by different crowders, suggesting that, in addition to the expected excluded volume effects, there are some changes in the solvent properties.

  17. Interconversion of Anthozoa GFP-like fluorescent and non-fluorescent proteins by mutagenesis

    Directory of Open Access Journals (Sweden)

    Mudrik Nikolay N

    2002-04-01

    Full Text Available Abstract Background Within the family of green fluorescent protein (GFP homologs, one can mark two main groups, specifically, fluorescent proteins (FPs and non-fluorescent or chromoproteins (CPs. Structural background of differences between FPs and CPs are poorly understood to date. Results Here, we applied site-directed and random mutagenesis in order to to transform CP into FP and vice versa. A purple chromoprotein asCP (asFP595 from Anemonia sulcata and a red fluorescent protein DsRed from Discosoma sp. were selected as representatives of CPs and FPs, respectively. For asCP, some substitutions at positions 148 and 165 (numbering in accordance to GFP were found to dramatically increase quantum yield of red fluorescence. For DsRed, substitutions at positions 148, 165, 167, and 203 significantly decreased fluorescence intensity, so that the spectral characteristics of these mutants became more close to those of CPs. Finally, a practically non-fluorescent mutant DsRed-NF was generated. This mutant carried four amino acid substitutions, specifically, S148C, I165N, K167M, and S203A. DsRed-NF possessed a high extinction coefficient and an extremely low quantum yield ( Conclusions We located a novel point in asCP sequence (position 165 mutations at which can result in red fluorescence appearance. Probably, this finding could be applied onto other CPs to generate red and far-red fluorescent mutants. A possibility to transform an FP into CP was demonstrated. Key role of residues adjacent to chromophore's phenolic ring in fluorescent/non-fluorescent states determination was revealed.

  18. The expression of GFP under the control of fibroin promotor in primary ovarian cells of Antheraea pernyi

    Indian Academy of Sciences (India)

    Wenli Li; Liji Jin; Pengcheng Bu; Lijia An

    2003-12-01

    The fibroin promoter can stably express foreign gene in lepidopteran cells. Total RNA was extracted from the gland of silkworm, Antheraea pernyi and the transcription initiation site of fibroin gene of A. pernyi was identified by RNA ligase mediated rapid amplification of cDNA ends (RLM-RACE). The expression vector (pGFP-N2/Fib) was constructed by use of replacing the CMV promoter with the fibroin promoter. The results of visual screening under a fluorescent inverted microscope and Western blot analysis indicated that the GFP gene was expressed in the primary cells of ovary origins from A. pernyi.

  19. Flight muscle-specific expression of act88F: GFP in transgenic Culex quinquefasciatus Say (Diptera: Culicidae).

    Science.gov (United States)

    Allen, Margaret L; Christensen, Bruce M

    2004-12-01

    A strategy to engineer a strain of Culex mosquitoes refractory to filarial transmission is described. A requirement for success of the strategy is identification of a flight muscle-specific promoter that functions in the mosquito. A GFP marker gene under the control of the promoter region of the Drosophila melanogaster act88F gene was inserted into the genome of Culex quinquefasciatus. Transformation was confirmed by Mendelian genetics. Hybridization of a genomic Southern blot to a radiolabeled probe verified that the entire donor plasmid integrated into the mosquito genome. GFP expression in the transgenic mosquitoes was restricted to the flight muscles.

  20. ASD-GFP vectors for in vivo expression technology in Pseudomonas aeruginosa and other gram-negative bacteria.

    Science.gov (United States)

    Handfield, M; Schweizer, H P; Mahan, M J; Sanschagrin, F; Hoang, T; Levesque, R C

    1998-02-01

    We describe the construction of promoter probe vectors designed for identification of bacterial genes induced in vitro and/or in vivo and for measurement of gene expression levels for in vivo expression technology. These plasmids use the Pseudomonas aeruginosa aspartate beta-semialdehyde dehydrogenase (asd) gene as a selectable marker and beta-galactosidase (pIVPRO, 10.88 kb) or mutant green fluorescent protein with enhanced fluorescence properties (mut3GFP, pIVET-GFP, 5.48 kb) as reporter gene systems. The proposed strategies can be adapted for use in most Gram-negative bacteria.

  1. Tumor-selective, adenoviral-mediated GFP genetic labeling of human cancer in the live mouse reports future recurrence after resection

    OpenAIRE

    2011-01-01

    We have previously developed a telomerase-specific replicating adenovirus expressing GFP (OBP-401), which can selectively label tumors in vivo with GFP. Intraperitoneal (i.p.) injection of OBP-401 specifically labeled peritoneal tumors with GFP, enabling fluorescence visualization of the disseminated disease and real-time fluorescence surgical navigation. However, the technical problems with removing all cancer cells still remain, even with fluorescence-guided surgery. In this study, we repor...

  2. The role of bone marrow-derived cells during the bone healing process in the GFP mouse bone marrow transplantation model.

    Science.gov (United States)

    Tsujigiwa, Hidetsugu; Hirata, Yasuhisa; Katase, Naoki; Buery, Rosario Rivera; Tamamura, Ryo; Ito, Satoshi; Takagi, Shin; Iida, Seiji; Nagatsuka, Hitoshi

    2013-03-01

    Bone healing is a complex and multistep process in which the origin of the cells participating in bone repair is still unknown. The involvement of bone marrow-derived cells in tissue repair has been the subject of recent studies. In the present study, bone marrow-derived cells in bone healing were traced using the GFP bone marrow transplantation model. Bone marrow cells from C57BL/6-Tg (CAG-EGFP) were transplanted into C57BL/6 J wild mice. After transplantation, bone injury was created using a 1.0-mm drill. Bone healing was histologically assessed at 3, 7, 14, and 28 postoperative days. Immunohistochemistry for GFP; double-fluorescent immunohistochemistry for GFP-F4/80, GFP-CD34, and GFP-osteocalcin; and double-staining for GFP and tartrate-resistant acid phosphatase were performed. Bone marrow transplantation successfully replaced the hematopoietic cells into GFP-positive donor cells. Immunohistochemical analyses revealed that osteoblasts or osteocytes in the repair stage were GFP-negative, whereas osteoclasts in the repair and remodeling stages and hematopoietic cells were GFP-positive. The results indicated that bone marrow-derived cells might not differentiate into osteoblasts. The role of bone marrow-derived cells might be limited to adjustment of the microenvironment by differentiating into inflammatory cells, osteoclasts, or endothelial cells in immature blood vessels.

  3. Tracking Monocyte Recruitment and Macrophage Accumulation in Atherosclerotic Plaque Progression Using a Novel hCD68GFP/ApoE−/− Reporter Mouse—Brief Report

    Science.gov (United States)

    Iqbal, Asif J.; Jones, Daniel; Patel, Jyoti; Coutinho, Patricia; Taylor, Lewis; Greaves, David R.; Channon, Keith M.

    2017-01-01

    Objective— To create a model of atherosclerosis using green fluorescent protein (GFP)–targeted monocytes/macrophages, allowing analysis of both endogenous GFP+ and adoptively transferred GFP+ myeloid cells in arterial inflammation. Approach and Results— hCD68GFP reporter mice were crossed with ApoE−/− mice. Expression of GFP was localized to macrophages in atherosclerotic plaques and in angiotensin II–induced aortic aneurysms and correlated with galectin 3 and mCD68 expression. Flow cytometry confirmed GFP+ expression in CD11b+/CD64+, CD11c+/MHC-IIHI, and CD11b+/F4/80+ myeloid cells. Adoptive transfer of GFP+ monocytes demonstrated monocyte recruitment to both adventitia and atherosclerotic plaque, throughout the aortic root, within 72 hours. We demonstrated the biological utility of hCD68GFP monocytes by comparing the recruitment of wild-type and CCR2−/− monocytes to sites of inflammation. Conclusions— hCD68GFP/ApoE−/− mice provide a new approach to study macrophage accumulation in atherosclerotic plaque progression and to identify cells recruited from adoptively transferred monocytes. PMID:27908893

  4. Modification of superoxide dismutase 1 (SOD1 properties by a GFP tag--implications for research into amyotrophic lateral sclerosis (ALS.

    Directory of Open Access Journals (Sweden)

    James C Stevens

    Full Text Available BACKGROUND: Since the discovery that mutations in the enzyme SOD1 are causative in human amyotrophic lateral sclerosis (ALS, many strategies have been employed to elucidate the toxic properties of this ubiquitously expressed mutant protein, including the generation of GFP-SOD1 chimaeric proteins for studies in protein localization by direct visualization using fluorescence microscopy. However, little is known about the biochemical and physical properties of these chimaeric proteins, and whether they behave similarly to their untagged SOD1 counterparts. METHODOLOGY/PRINCIPAL FINDINGS: Here we compare the physicochemical properties of SOD1 and the effects of GFP-tagging on its intracellular behaviour. Immunostaining demonstrated that SOD1 alone and GFP-SOD1 have an indistinguishable intracellular distribution in PC12 cells. Cultured primary motor neurons expressing GFP or GFP-SOD1 showed identical patterns of cytoplasmic expression and of movement within the axon. However, GFP tagging of SOD1 was found to alter some of the intrinsic properties of SOD1, including stability and specific activity. Evaluation of wildtype and mutant SOD1, tagged at either the N- or C-terminus with GFP, in PC12 cells demonstrated that some chimaeric proteins were degraded to the individual proteins, SOD1 and GFP. CONCLUSIONS/SIGNIFICANCE: Our findings indicate that most, but not all, properties of SOD1 remain the same with a GFP tag.

  5. 嗜肺军团菌mip基因重组质粒GFP-mip的构建及表达%The Construction and Expression of Recombinant Plasmid GFP -mip of Legionella Pneumophila Macrophage Infectivity Potentiator Gene

    Institute of Scientific and Technical Information of China (English)

    惠英华; 曹秀琴; 杨志伟

    2011-01-01

    Objective To construct recombinant plasmid GFP - mip of Legionella pneumophila macrophage infectivity potentiator gene and observe its expression in the NIH3T3 cells. Methods The macrophage infectivity potentiator gene was amplified from DNA of Legionella pneumophila by polymerase chain reation ( PCR),then cloned into pEGFP - C1 vector. The recombinant plasmid was named as GFP - mip and was analyzed with restriction endonuclease XhoI and BarnHl digestion, PCR and DNA sequencing techniques. The NIH3T3 cell was transfected by recombinant plasmid GFP - mip with lipofection strategy. The stable expression products of macrophage infectivity petentiator gene were observed by the fluorescent microscope. Results 702bp mip gene was amplified . Under the fluorescent microscope, green fluorescent was observed in the cell cytoplasm and on the cell membrane. Conclusion The recombinant plasmid GFP - mip was constructed successfully and expressed in the NIH3T3 cells.%目的构建嗜肺军团菌mip基因的真核重组质粒GFP-mip,并观察其在NIH3T3细胞中的表达.方法 以嗜肺军团菌DNA为模版,通过PCR扩增获得mip基因,将其定向克隆到绿色荧光质粒pEGFP-C1中,构建真核重组质粒GFP-mip.经限制性核酸内切酶XhoI和BamHI酶切鉴定、PCR和核酸序列分析后,通过脂质体法转染到NIH3T3细胞中,利用荧光显微镜观察重组质粒的稳定表达.结果 扩增出了702bpmip基因,在细胞质和细胞膜观察到较强绿色荧光.结论 成功构建了真核重组质粒GFP-mip,并在NIH3T3细胞中得到了表达.

  6. Inhibitory Interneurons That Express GFP in the PrP-GFP Mouse Spinal Cord Are Morphologically Heterogeneous, Innervated by Several Classes of Primary Afferent and Include Lamina I Projection Neurons among Their Postsynaptic Targets.

    Science.gov (United States)

    Ganley, Robert P; Iwagaki, Noboru; del Rio, Patricia; Baseer, Najma; Dickie, Allen C; Boyle, Kieran A; Polgár, Erika; Watanabe, Masahiko; Abraira, Victoria E; Zimmerman, Amanda; Riddell, John S; Todd, Andrew J

    2015-05-13

    The superficial dorsal horn of the spinal cord contains numerous inhibitory interneurons, which regulate the transmission of information perceived as touch, pain, or itch. Despite the importance of these cells, our understanding of their roles in the neuronal circuitry is limited by the difficulty in identifying functional populations. One group that has been identified and characterized consists of cells in the mouse that express green fluorescent protein (GFP) under control of the prion protein (PrP) promoter. Previous reports suggested that PrP-GFP cells belonged to a single morphological class (central cells), received inputs exclusively from unmyelinated primary afferents, and had axons that remained in lamina II. However, we recently reported that the PrP-GFP cells expressed neuronal nitric oxide synthase (nNOS) and/or galanin, and it has been shown that nNOS-expressing cells are more diverse in their morphology and synaptic connections. We therefore used a combined electrophysiological, pharmacological, and anatomical approach to reexamine the PrP-GFP cells. We provide evidence that they are morphologically diverse (corresponding to "unclassified" cells) and receive synaptic input from a variety of primary afferents, with convergence onto individual cells. We also show that their axons project into adjacent laminae and that they target putative projection neurons in lamina I. This indicates that the neuronal circuitry involving PrP-GFP cells is more complex than previously recognized, and suggests that they are likely to have several distinct roles in regulating the flow of somatosensory information through the dorsal horn.

  7. Heavy water reduces GFP expression in prokaryotic cell-free assays at the translation level while stimulating its transcription.

    Science.gov (United States)

    Hohlefelder, Luisa S; Stögbauer, Tobias; Opitz, Madeleine; Bayerl, Thomas M; Rädler, Joachim O

    2013-01-01

    The in vitro proliferation of prokaryotic and eukaryotic cells is remarkably hampered in the presence of heavy water (D2O). Impairment of gene expression at the transcription or translation level can be the base for this effect. However, insights into the underlying mechanisms are lacking. Here, we employ a cell-free expression system for the quantitative analysis of the effect of increasing percentages of D2O on the kinetics of in-vitro GFP expression. Experiments are designed to discriminate the rates of transcription, translation, and protein folding using pDNA and mRNA vectors, respectively. We find that D2O significantly stimulates GFP expression at the transcription level but acts as a suppressor at translation and maturation (folding) in a linear dose-dependent manner. At a D2O concentration of 60%, the GFP expression rate was reduced to 40% of an undisturbed sample. We observed a similar inhibition of GFP expression by D2O in a recombinant Escherichia coli strain, although the inhibitory effect is less pronounced. These results demonstrate the suitability of cell-free systems for quantifying the impact of heavy water on gene expression and establish a platform to further assess the potential therapeutic use of heavy water as antiproliferative agent.

  8. Monitoring apoptosis of TK-GFP-expressing ACC-M cells induced by ACV using FRET technique

    Science.gov (United States)

    Xiong, Tao; Zhang, Zhihong; Lin, Juqiang; Yang, Jie; Zeng, Shaoqun; Luo, Qingming

    2006-09-01

    Apoptosis is an evolutionary conserved cellular process that plays an important role during development, but it is also involved in tissue homeostasis and in many diseases. To study the characteristics of suicide gene system of the herpes simplex virus thymidine kinase (HSV-tk) gene in tumor cells and explore the apoptosis phenomena in this system and its effect on the human adenoid cystic carcinoma line ACC-M cell, we detected apoptosis of CD3- (ECFP-CRS-DsRed) and TK-GFP-expressing ACC-M (ACC-M-TK-GFP-CD3) cells induced by acyclovir (ACV) using fluorescence resonance energy transfer (FRET) technique. CD3 is a FRET-based indicator for activity of caspase-3, which is composed of an enhanced cyan fluorescent protein, a caspase-3 sensitive linker, and a red fluorescent protein from Discosoma with efficient maturation property. FRET from ECFP to DsRed could be detected in normal ACC-M-TK-GFP-CD3 cells, and the FRET efficient was remarkably decreased and then disappeared during the cells apoptosis induced by ACV. It was due to the activated caspase-3 cleaved the CD3 fusion protein. In this study, the results suggested that the AVC-induced apoptosis of ACC-M-TK-GFP-CD3 cells was through caspase-3 pathway.

  9. Prox1 expression in the endolymphatic sac revealed by whole-mount fluorescent imaging of Prox1-GFP transgenic mice.

    Science.gov (United States)

    Miyashita, Takenori; Burford, James L; Hong, Young-Kwon; Gevorgyan, Haykanush; Lam, Lisa; Hoshikawa, Hiroshi; Mori, Nozomu; Peti-Peterdi, Janos

    2015-01-30

    This study describes a technical breakthrough in endolymphatic sac research, made possible by the use of the recently generated Prox1-GFP transgenic mouse model. Whole-mount imaging techniques through the decalcified temporal bone and three-dimensional observations of Prox1-GFP mouse tissue revealed the positive labeling of the endolymphatic sac in adult stage, and allowed, for the first time, the GFP-based identification of endolymphatic sac epithelial cells. Prox1 expression was observed in all parts of the endolymphatic sac epithelia. In intermediate portion of the endolymphatic sac, mitochondria-rich cells did not express Prox1, although ribosome-rich cells showed strong GFP labeling. The anatomical relationship between the endolymphatic sac and the surrounding vasculature was directly observed. In the endolymphatic sac, expression of Prox1 may suggest progenitor cell-like pluripotency or developmental similarity to systemic lymphatic vessels in other organs. This whole-mount imaging technique of the endolymphatic sac can be combined with other conventional histological, sectioning, and labeling techniques and will be very useful for future endolymphatic sac research.

  10. Screening estrogenic activities of chemicals or mixtures in vivo using transgenic (cyp19a1b-GFP zebrafish embryos.

    Directory of Open Access Journals (Sweden)

    François Brion

    Full Text Available The tg(cyp19a1b-GFP transgenic zebrafish expresses GFP (green fluorescent protein under the control of the cyp19a1b gene, encoding brain aromatase. This gene has two major characteristics: (i it is only expressed in radial glial progenitors in the brain of fish and (ii it is exquisitely sensitive to estrogens. Based on these properties, we demonstrate that natural or synthetic hormones (alone or in binary mixture, including androgens or progestagens, and industrial chemicals induce a concentration-dependent GFP expression in radial glial progenitors. As GFP expression can be quantified by in vivo imaging, this model presents a very powerful tool to screen and characterize compounds potentially acting as estrogen mimics either directly or after metabolization by the zebrafish embryo. This study also shows that radial glial cells that act as stem cells are direct targets for a large panel of endocrine disruptors, calling for more attention regarding the impact of environmental estrogens and/or certain pharmaceuticals on brain development. Altogether these data identify this in vivo bioassay as an interesting alternative to detect estrogen mimics in hazard and risk assessment perspective.

  11. Screening estrogenic activities of chemicals or mixtures in vivo using transgenic (cyp19a1b-GFP) zebrafish embryos.

    Science.gov (United States)

    Brion, François; Le Page, Yann; Piccini, Benjamin; Cardoso, Olivier; Tong, Sok-Keng; Chung, Bon-chu; Kah, Olivier

    2012-01-01

    The tg(cyp19a1b-GFP) transgenic zebrafish expresses GFP (green fluorescent protein) under the control of the cyp19a1b gene, encoding brain aromatase. This gene has two major characteristics: (i) it is only expressed in radial glial progenitors in the brain of fish and (ii) it is exquisitely sensitive to estrogens. Based on these properties, we demonstrate that natural or synthetic hormones (alone or in binary mixture), including androgens or progestagens, and industrial chemicals induce a concentration-dependent GFP expression in radial glial progenitors. As GFP expression can be quantified by in vivo imaging, this model presents a very powerful tool to screen and characterize compounds potentially acting as estrogen mimics either directly or after metabolization by the zebrafish embryo. This study also shows that radial glial cells that act as stem cells are direct targets for a large panel of endocrine disruptors, calling for more attention regarding the impact of environmental estrogens and/or certain pharmaceuticals on brain development. Altogether these data identify this in vivo bioassay as an interesting alternative to detect estrogen mimics in hazard and risk assessment perspective.

  12. Engineering color variants of green fluorescent protein (GFP) for thermostability, pH-sensitivity, and improved folding kinetics.

    Science.gov (United States)

    Aliye, Naser; Fabbretti, Attilio; Lupidi, Giulio; Tsekoa, Tsepo; Spurio, Roberto

    2015-02-01

    A number of studies have been conducted to improve chromophore maturation, folding kinetics, thermostability, and other traits of green fluorescent protein (GFP). However, no specific work aimed at improving the thermostability of the yellow fluorescent protein (YFP) and of the pH-sensitive, yet thermostable color variants of GFP has so far been done. The protein variants reported in this study were improved through rational multiple site-directed mutagenesis of GFP (ASV) by introducing up to ten point mutations including the mutations near and at the chromophore region. Therefore, we report the development and characterization of fast folder and thermo-tolerant green variant (FF-GFP), and a fast folder thermostable yellow fluorescent protein (FFTS-YFP) endowed with remarkably improved thermostability and folding kinetics. We demonstrate that the fluorescence intensity of this yellow variant is not affected by heating at 75 °C. Moreover, we have developed a pH-unresponsive cyan variant AcS-CFP, which has potential use as part of in vivo imaging irrespective of intracellular pH. The combined improved properties make these fluorescent variants ideal tools to study protein expression and function under different pH environments, in mesophiles and thermophiles. Furthermore, coupling of the FFTS-YFP and AcS-CFP could potentially serve as an ideal tool to perform functional analysis of live cells by multicolor labeling.

  13. Green fluorescent protein (GFP) as a vital marker for studying the interaction of Phytophthora sojae and soybean

    Institute of Scientific and Technical Information of China (English)

    CHEN XiaoRen; CHENG BaoPing; WANG XinLe; DONG SuoMeng; WANG YongLin; ZHENG XiaoBo; WANG YuanChao

    2009-01-01

    Transgenic Phytophthora sojae strains that produce green fluorescent protein (GFP) were obtained after stable DNA integration using the Hsp70 promoter and the Ham34 terminator of Bremia lactucae.The expression of GFP during different developmental stages of P.sojae was observed using fluorescent microscopy.Based on this reporter system,the histopathologic events caused by the pathogen in soybean leaves,hypocotyls and roots were monitored.Meanwhile,the difference in resistance between different soybean cultivars against P.sojae was analyzed microscopically in roots.The results indicate that GFP can be stably expressed in zoosporangia,zoospores,cysts,hyphae and oospores of .sojae.Using the GFP marker,the infecting pathogens in leaves,hypocotyls and roots of host could be distinctly visualized.The germ tube length of cysts germinating on the roots of resistant cultivar Nannong 8848 was longer than that on the roots of susceptible culUvar Hefeng 35.These results show for the first time that this eukaryotic reporter can be used in P.sojae as a stable and vital marker,allowing the study of genetics of this hemibiotrophic pathogen.

  14. Quantification of contamination of lettuce by GFP-expressing Escherichia coli O157:H7 and Salmonella enterica serovar Typhimurium

    NARCIS (Netherlands)

    Franz, E.; Visser, A.A.; Diepeningen, van A.D.; Klerks, M.M.; Termorshuizen, A.J.; Bruggen, van A.H.C.

    2007-01-01

    The primary objective of this study was to determine the possibility of internalization of GFP-expressing Escherichia coli O157:H7 and Salmonella enterica serovar Typhimurium (S. Typhimurium) strains MAE 110 (multi-cellular morphology) and 119 (wild type morphology) into lettuce seedlings (Lactuca

  15. Quantification of contamination of lettuce by GFP-expressing Escherichia coli O157:H7 and Salmonella enterica serovar Typhimurium

    NARCIS (Netherlands)

    Franz, Eelco; Visser, Anna A; Van Diepeningen, Anne D; Klerks, Michel M; Termorshuizen, Aad J; van Bruggen, Ariena H C

    The primary objective of this study was to determine the possibility of internalization of GFP-expressing Escherichia coli O157:H7 and Salmonella enterica serovar Typhimurium (S. Typhimurium) strains MAE 110 (multi-cellular morphology) and 119 (wild type morphology) into lettuce seedlings (Lactuca

  16. Deployment of a Prototype Plant GFP Imager at the Arthur Clarke Mars Greenhouse of the Haughton Mars Project.

    Science.gov (United States)

    Paul, Anna-Lisa; Bamsey, Matthew; Berinstain, Alain; Braham, Stephen; Neron, Philip; Murdoch, Trevor; Graham, Thomas; Ferl, Robert J

    2008-04-18

    The use of engineered plants as biosensors has made elegant strides in the past decades, providing keen insights into the health of plants in general and particularly in the nature and cellular location of stress responses. However, most of the analytical procedures involve laboratory examination of the biosensor plants. With the advent of the green fluorescence protein (GFP) as a biosensor molecule, it became at least theoretically possible for analyses of gene expression to occur telemetrically, with the gene expression information of the plant delivered to the investigator over large distances simply as properly processed fluorescence images. Spaceflight and other extraterrestrial environments provide unique challenges to plant life, challenges that often require changes at the gene expression level to accommodate adaptation and survival. Having previously deployed transgenic plant biosensors to evaluate responses to orbital spaceflight, we wished to develop the plants and especially the imaging devices required to conduct such experiments robotically, without operator intervention, within extraterrestrial environments. This requires the development of an autonomous and remotely operated plant GFP imaging system and concomitant development of the communications infrastructure to manage dataflow from the imaging device. Here we report the results of deploying a prototype GFP imaging system within the Arthur Clarke Mars Greenhouse (ACMG) an autonomously operated greenhouse located within the Haughton Mars Project in the Canadian High Arctic. Results both demonstrate the applicability of the fundamental GFP biosensor technology and highlight the difficulties in collecting and managing telemetric data from challenging deployment environments.

  17. Deployment of a Prototype Plant GFP Imager at the Arthur Clarke Mars Greenhouse of the Haughton Mars Project

    Directory of Open Access Journals (Sweden)

    Robert J. Ferl

    2008-04-01

    Full Text Available The use of engineered plants as biosensors has made elegant strides in the past decades, providing keen insights into the health of plants in general and particularly in the nature and cellular location of stress responses. However, most of the analytical procedures involve laboratory examination of the biosensor plants. With the advent of the green fluorescence protein (GFP as a biosensor molecule, it became at least theoretically possible for analyses of gene expression to occur telemetrically, with the gene expression information of the plant delivered to the investigator over large distances simply as properly processed fluorescence images. Spaceflight and other extraterrestrial environments provide unique challenges to plant life, challenges that often require changes at the gene expression level to accommodate adaptation and survival. Having previously deployed transgenic plant biosensors to evaluate responses to orbital spaceflight, we wished to develop the plants and especially the imaging devices required to conduct such experiments robotically, without operator intervention, within extraterrestrial environments. This requires the development of an autonomous and remotely operated plant GFP imaging system and concomitant development of the communications infrastructure to manage dataflow from the imaging device. Here we report the results of deploying a prototype GFP imaging system within the Arthur Clarke Mars Greenhouse (ACMG an autonomously operated greenhouse located within the Haughton Mars Project in the Canadian High Arctic. Results both demonstrate the applicability of the fundamental GFP biosensor technology and highlight the difficulties in collecting and managing telemetric data from challenging deployment environments.

  18. Quantification of contamination of lettuce by GFP-expressing Escherichia coli O157:H7 and Salmonella enterica serovar Typhimurium

    NARCIS (Netherlands)

    Franz, Eelco; Visser, Anna A; Van Diepeningen, Anne D; Klerks, Michel M; Termorshuizen, Aad J; van Bruggen, Ariena H C

    2007-01-01

    The primary objective of this study was to determine the possibility of internalization of GFP-expressing Escherichia coli O157:H7 and Salmonella enterica serovar Typhimurium (S. Typhimurium) strains MAE 110 (multi-cellular morphology) and 119 (wild type morphology) into lettuce seedlings (Lactuca s

  19. Green fluorescent protein (GFP) leakage from microbial biosensors provides useful information for the evaluation of the scale-down effect

    DEFF Research Database (Denmark)

    Delvigne, Frank; Brognaux, Alison; Francis, Frédéric

    2011-01-01

    -shift of the dilution rate in chemostat mode. Glucose limitation was accompanied by green fluorescent protein (GFP) leakage to the extracellular medium. In order to test the responsiveness of microbial biosensors to substrate fluctuations in large-scale, a scale-down reactor (SDR) experiment was performed. The glucose...

  20. Using of green fluorescent reporter gene (GFP) to monitor the fate of Fusarium moniliforme mycoparasitized by Trichoderma viride

    Institute of Scientific and Technical Information of China (English)

    ZHU Ting-heng; WANG Wei-xia; WANG Chang-chun; YANG Rui-qin; CAI Xin-zhong

    2004-01-01

    @@ Fusarium moniliforme Sheld. is a rice pathogenic fungus and causes the disease called Bakanae,which has increasingly damaged rice production in the recent years. Trichoderma spp. has been one of the most widely used biological control agent of plant disease. By geneticaly labelling F. moniliforme with the GFP reporter gene, we have studied the antagonistic action of Trichoderma viride against this pathogenic fungus.

  1. A new way to rapidly create functional, fluorescent fusion proteins: random insertion of GFP with an in vitro transposition reaction

    Directory of Open Access Journals (Sweden)

    Jakobsdottir Klara B

    2002-06-01

    Full Text Available Abstract Background The jellyfish green fluorescent protein (GFP can be inserted into the middle of another protein to produce a functional, fluorescent fusion protein. Finding permissive sites for insertion, however, can be difficult. Here we describe a transposon-based approach for rapidly creating libraries of GFP fusion proteins. Results We tested our approach on the glutamate receptor subunit, GluR1, and the G protein subunit, αs. All of the in-frame GFP insertions produced a fluorescent protein, consistent with the idea that GFP will fold and form a fluorophore when inserted into virtually any domain of another protein. Some of the proteins retained their signaling function, and the random nature of the transposition process revealed permissive sites for insertion that would not have been predicted on the basis of structural or functional models of how that protein works. Conclusion This technique should greatly speed the discovery of functional fusion proteins, genetically encodable sensors, and optimized fluorescence resonance energy transfer pairs.

  2. Medial prefrontal cortex neuronal activation and synaptic alterations after stress-induced reinstatement of palatable food seeking: a study using c-fos-GFP transgenic female rats.

    Science.gov (United States)

    Cifani, Carlo; Koya, Eisuke; Navarre, Brittany M; Calu, Donna J; Baumann, Michael H; Marchant, Nathan J; Liu, Qing-Rong; Khuc, Thi; Pickel, James; Lupica, Carl R; Shaham, Yavin; Hope, Bruce T

    2012-06-20

    Relapse to maladaptive eating habits during dieting is often provoked by stress and there is evidence for a role of ovarian hormones in stress responses and feeding. We studied the role of these hormones in stress-induced reinstatement of food seeking and medial prefrontal cortex (mPFC) neuronal activation in c-fos-GFP transgenic female rats, which express GFP in strongly activated neurons. Food-restricted ovariectomized or sham-operated c-fos-GFP rats were trained to lever-press for palatable food pellets. Subsequently, lever-pressing was extinguished and reinstatement of food seeking and mPFC neuronal activation was assessed after injections of the pharmacological stressor yohimbine (0.5-2 mg/kg) or pellet priming (1-4 noncontingent pellets). Estrous cycle effects on reinstatement were also assessed in wild-type rats. Yohimbine- and pellet-priming-induced reinstatement was associated with Fos and GFP induction in mPFC; both reinstatement and neuronal activation were minimally affected by ovarian hormones in both c-fos-GFP and wild-type rats. c-fos-GFP transgenic rats were then used to assess glutamatergic synaptic alterations within activated GFP-positive and nonactivated GFP-negative mPFC neurons following yohimbine-induced reinstatement of food seeking. This reinstatement was associated with reduced AMPA receptor/NMDA receptor current ratios and increased paired-pulse facilitation in activated GFP-positive but not GFP-negative neurons. While ovarian hormones do not appear to play a role in stress-induced relapse of food seeking in our rat model, this reinstatement was associated with unique synaptic alterations in strongly activated mPFC neurons. Our paper introduces the c-fos-GFP transgenic rat as a new tool to study unique synaptic changes in activated neurons during behavior.

  3. Cap analog and Potato virus A HC-Pro silencing suppressor improve GFP transient expression using an infectious virus vector in Nicotiana benthamiana.

    Science.gov (United States)

    Tahmasebi, Amin-Alah; Afsharifar, Alireza

    2017-06-01

    Transient expression of proteins in plants has become a choice to facilitate recombinant protein production with its fast and easy application. On the other hand, host defensive mechanisms have been reported to reduce the efficiency of transient expression in plants. Hence, this study was designed to evaluate the effect of cap analog and Potato virus A helper component proteinase (PVA HC-Pro) on green fluorescent protein (GFP) expression efficiency. N. benthamiana leaves were inoculated with capped or un-capped RNA transcripts of a Turnip crinkle virus (TCV) construct containing a green fluorescent protein reporter gene (TCV-sGFP) in place of its coat protein (CP) ORF. PVA HC-Pro as a viral suppressor of RNA silencing was infiltrated in trans by Agrobacterium tumefaciens, increased the GFP foci diameter to six and even more cells in both capped and un capped treatments. The expression level of GFP in inoculated plants with TCV-sGFP transcript pre-infiltrated with PVA HC-Pro was 12.97-fold higher than the GFP accumulation level in pre-infiltrated leaves with empty plasmid (EP) control. Also, the yield of GFP in inoculated N. benthamiana plants with capped TCV-sGFP transcript pre-infiltrated with EP and PVA HC-Pro was 1.54 and 1.2-fold respectively, greater than the level of GFP expressed without cap analog application at 5 days post inoculation (dpi). In addition, the movement of TCV-sGFP was increased in some cells of inoculated leaves with capped transcripts. Results of this study indicated that PVA HC-Pro and mRNA capping can increase GFP expression and its cell to cell movement in N. benthamiana.

  4. Following the infection process of vibriosis in Manila clam (Ruditapes philippinarum) larvae through GFP-tagged pathogenic Vibrio species.

    Science.gov (United States)

    Dubert, Javier; Nelson, David R; Spinard, Edward J; Kessner, Linda; Gomez-Chiarri, Marta; da Costa, Fiz; Prado, Susana; Barja, Juan L

    2016-01-01

    Vibriosis represents the main bottleneck for the larval production process in shellfish aquaculture. While the signs of this disease in bivalve larvae are well known, the infection process by pathogenic Vibrio spp. during episodes of vibriosis has not been elucidated. To investigate the infection process in bivalves, the pathogens of larvae as V. tubiashii subsp. europaensis, V. neptunius and V. bivalvicida were tagged with green fluorescent protein (GFP). Larvae of Manila clam (Ruditapes philippinarum) were inoculated with the GFP-labeled pathogens in different infection assays and monitored by microscopy. Manila clam larvae infected by distinct GFP-tagged Vibrio spp. in different challenges showed the same progression in the infection process, defining three infection stages. GFP-tagged Vibrio spp. were filtered by the larvae through the vellum and entered in the digestive system through the esophagus and stomach and colonized the digestive gland and particularly the intestine, where they proliferated during the first 2h of contact (Stage I), suggesting a chemotactic response. Then, GFP-tagged Vibrio spp. expanded rapidly to the surrounding organs in the body cavity from the dorsal to ventral region (Stage II; 6-8h), colonizing the larvae completely at the peak of infection (Stage III) (14-24h). Results demonstrated for the first time that the vibriosis is asymptomatic in Manila clam larvae during the early infection stages. Thus, the early colonization and the rapid proliferation of Vibrio pathogens within the body cavity supported the sudden and fatal effect of the vibriosis, since the larvae exhibited the first signs of disease when the infection process is advanced. As a first step in the elucidation of the potential mechanisms of bacterial pathogenesis in bivalve larvae the enzymatic activities of the extracellular products released from the wild type V. neptunius, V. tubiashii subsp. europaensis and V. bivalvicida were determined and their cytotoxicity was

  5. Variation in Growth, Colonization of Maize, and Metabolic Parameters of GFP- and DsRed-Labeled Fusarium verticillioides Strains.

    Science.gov (United States)

    Wu, Lei; Conner, R L; Wang, Xiaoming; Xu, Rongqi; Li, Hongjie

    2016-08-01

    Autofluorescent proteins are frequently applied as visual markers in the labeling of filamentous fungi. Genes gfp and DsRed were transformed into the genome of Fusarium verticillioides via the Agrobacterium tumefaciens-mediated transformation method. The selected transformants displayed a bright green or red fluorescence in all the organelles of the growing fungal mycelia and spores (except for the vacuoles) both in cultures and in the maize (Zea mays) roots they colonized. The results of gene-specific polymerase chain reaction (PCR) analysis and the thermal asymmetrical interlaced (TAIL)-PCR analysis demonstrated that gfp and DsRed were integrated on different chromosomes of the fungus. Reductions in the colony growth on the plates at pH 4.0 and 5.5 was observed for the green fluorescent protein (GFP)-transformant G3 and the DsRed-transformant R4, but transformants G4 and R1 grew as well as the wild-type strain at pH 4.0. The speed of growth of all the transformants was similar to the wild-type strain at pH ≥ 7. The insertion of gfp and DsRed did not alter the production of extracellular enzymes and fumonisin B by F. verticillioides. The transformants expressing GFP and DsRed proteins were able to colonize maize roots. However, the four transformants examined produced fewer CFU in the root samples than the wild-type strain during a sampling period of 7 to 28 days after inoculation.

  6. Transient and Stable GFP Expression in Germ Cells by the vasa Regulatory Sequences from the Red Seabream (Pagrus major

    Directory of Open Access Journals (Sweden)

    Fan Lin, Qinghua Liu, Mingyou Li, Zhendong Li, Ni Hong, Jun Li, Yunhan Hong

    2012-01-01

    Full Text Available Primordial germ cells (PGCs are the precursors of gametes responsible for genetic transmission to the next generation. They provide an ideal system for cryopreservation and restoration of biodiversity. Recently, considerable attention has been raised to visualize, isolate and transplant PGCs within and between species. In fish, stable PGC visualization in live embryo and individual has been limited to laboratory fish models such as medaka and zebrafish. One exception is the rainbow trout, which represents the only species with aquaculture importance and has GFP-labeled germ cells throughout development. PGCs can be transiently labeled by embryonic injection of mRNA containing green fluorescence protein gene (GFP and 3'-untranslated region (3'-UTR of a maternal germ gene such as vasa, nos1, etc. Stable PGC labeling can be achieved through production of transgenic animals by some transcriptional regulatory sequences from germ genes, such as the vasa promoter and 3'-UTR. In this study, we reported the functional analyses of the red seabream vasa (Pmvas regulatory sequences, using medaka as a model system. It was showed that injection of GFP-Pmvas3'UTR mRNA was able to label medaka PGCs during embryogenesis. Besides, we have constructed pPmvasGFP transgenic vector, and established a stable transgenic medaka line exhibiting GFP expression in germ cells including PGCs, mitotic and meiotic germ cells of both sexes, under control of the Pmvas transcriptional regulatory sequences. It is concluded that the Pmvas regulatory sequences examined in this study are sufficient for germ cell expression and labeling.

  7. Embryonic stem cells and mice expressing different GFP variants for multiple non-invasive reporter usage within a single animal

    Directory of Open Access Journals (Sweden)

    Macmaster Suzanne

    2002-06-01

    Full Text Available Abstract Background Non-invasive autofluorescent reporters have revolutionized lineage labeling in an array of different organisms. In recent years green fluorescent protein (GFP from the bioluminescent jellyfish Aequoria Victoria has gained popularity in mouse transgenic and gene targeting regimes 1. It offers several advantages over conventional gene-based reporters, such as lacZ and alkaline phosphatase, in that its visualization does not require a chromogenic substrate and can be realized in vivo. We have previously demonstrated the utility and developmental neutrality of enhanced green fluorescent protein (EGFP in embryonic stem (ES cells and mice 2. Results In this study we have used embryonic stem (ES cell-mediated transgenesis to test the enhanced cyan fluorescent protein (ECFP and enhanced yellow fluorescent protein (EYFP, two mutant and spectrally distinct color variants of wild type (wt GFP. We have also tested DsRed1, the novel red fluorescent protein reporter recently cloned from the Discostoma coral by virtue of its homology to GFP. To this end, we have established lines of ES cells together with viable and fertile mice having widespread expression of either the ECFP or EYFP GFP-variant reporters. However, we were unable to generate equivalent DsRed1 lines, suggesting that DsRed1 is not developmentally neutral or that transgene expression cannot be sustained constitutively. Balanced (diploid diploid and polarized (tetraploid diploid chimeras comprising combinations of the ECFP and EYFP ES cells and/or embryos, demonstrate that populations of cells expressing each individual reporter can be distinguished within a single animal. Conclusions GFP variant reporters are unique in allowing non-invasive multi-spectral visualization in live samples. The ECFP and EYFP-expressing transgenic ES cells and mice that we have generated provide sources of cells and tissues for combinatorial, double-tagged recombination experiments, chimeras or

  8. A mathematical analysis of nuclear intensity dynamics for Mig1-GFP under consideration of bleaching effects and background noise in Saccharomyces cerevisiae.

    Science.gov (United States)

    Frey, Simone; Sott, Kristin; Smedh, Maria; Millat, Thomas; Dahl, Peter; Wolkenhauer, Olaf; Goksör, Mattias

    2011-01-01

    Fluorescence microscopy is an imaging technique that provides insights into signal transduction pathways through the generation of quantitative data, such as the spatiotemporal distribution of GFP-tagged proteins in signaling pathways. The data acquired are, however, usually a composition of both the GFP-tagged proteins of interest and of an autofluorescent background, which both undergo photobleaching during imaging. We here present a mathematical model based on ordinary differential equations that successfully describes the shuttling of intracellular Mig1-GFP under changing environmental conditions regarding glucose concentration. Our analysis separates the different bleaching rates of Mig1-GFP and background, and the background-to-Mig1-GFP ratio. By applying our model to experimental data, we can thus extract the Mig1-GFP signal from the overall acquired signal and investigate the influence of kinase and phosphatase on Mig1. We found a stronger regulation of Mig1 through its kinase than through its phosphatase when controlled by the glucose concentration, with a constant (de)phosphorylation rate independent of the glucose concentration. By replacing the term for decreasing excited Mig1-GFP concentration with a constant, we were able to reconstruct the dynamics of Mig1-GFP, as it would occur without bleaching and background noise. Our model effectively demonstrates how data, acquired with an optical microscope, can be processed and used for a systems biology analysis of signal transduction pathways.

  9. Estrogenic activity of alkylphenols, bisphenol S, and their chlorinated derivatives using a GFP expression system.

    Science.gov (United States)

    Kuruto-Niwa, Ryoko; Nozawa, Ryushi; Miyakoshi, Takashi; Shiozawa, Tatsushi; Terao, Yoshiyasu

    2005-01-01

    Alkylphenol ethoxylates, widely used non-ionic surfactants, are biodegraded into alkylphenols such as nonylphenol (NP) and t-octylphenol (OP), short-chain ethoxylates such as NP-monoethoxylate (NP1EO) and NP-diethoxylate (NP2EO), and alkylphenoxy carboxylic acids such as 4-t-octylphenoxyacetic acid (OP1EC). Bisphenol S (BPS) is more heat-stable and photo-resistant than bisphenol A (BPA), and therefore replaces BPA. These chemicals could be chlorinated during wastewater treatment. We synthesized these compounds and their chlorinated derivatives to estimate their estrogenic activities using a GFP expression system. The EC(50) ranking of NP-related compounds was NP > ClNP > diClNP > NP1EO > ClNP1EO > NP2EO. The estrogenic activity of OP1EC was 10 times less potent than parent OP. Furthermore, BPS showed comparable estrogenic activity with BPA. The EC(50) ranking of BPS-related compounds was BPA ≥ BPS > triClBPS > diClBPS > ClBPS. Other tested BPS derivatives had no estrogenic activity. Chlorination of the tested chemicals did not enhance their estrogenic activity, in contrast to certain chlorinated BPAs. Thus, our results demonstrated that chlorinated derivatives of NP, OP, and BPS, even if artificially produced during wastewater processing, were less estrogenic than their parent chemicals, known as endocrine disruptors.

  10. Gas Replacements for GFP to Track Microbial Dynamics in Soils and Sediments

    Science.gov (United States)

    Cheng, Hsiao-Ying; Silberg, Jonathan; Masiello, Caroline

    2016-04-01

    Metagenomic analyses offer unprecedented views of soil microbial communities, and additionally provide a host of testable hypotheses about the biological mechanisms driving global biogeochemical fluxes. Outside the biogeosciences, hypotheses generated by metagenomics are often tested using biosensors, microbes programmed to respond in a detectable way to either changes in their metabolism or changes in the environment. A very large number of microbial behaviors can be monitored using biosensors, but these sensors typically report in ways that are undetectable in soils, e.g. by releasing green fluorescent protein (GFP). We are building a new class of biosensors that report by releasing easily-detected gases. We will provide an overview of the potential uses of gas-reporting biosensors in geobiology, and will report the current development these sensors. One goal in the development of these sensors is to make tractable the testing of gene expression hypotheses derived from metagenomics data. Examples of processes that could be tracked non-invasively with gas sensors include coordination of biofilm formation, nitrification, rhizobial infection of plant roots, and at least some forms of methanogenesis, all of which are managed by the easily-engineered acyl homoserine lactone cell-cell communication system. Another relatively simple process to track with gas sensors is horizontal gene transfer. We will report on the progress of these proof-of-concept examples.

  11. Using multiplexed regulation of luciferase activity and GFP translocation to screen for FOXO modulators

    Directory of Open Access Journals (Sweden)

    Carnero Amancio

    2009-02-01

    Full Text Available Abstract Background Independent luciferase reporter assays and fluorescent translocation assays have been successfully used in drug discovery for several molecular targets. We developed U2transLUC, an assay system in which luciferase and fluorescent read-outs can be multiplexed to provide a powerful cell-based high content screening method. Results The U2transLUC system is based on a stable cell line expressing a GFP-tagged FOXO transcription factor and a luciferase reporter gene under the control of human FOXO-responsive enhancers. The U2transLUC assay measures nuclear-cytoplasmic FOXO shuttling and FOXO-driven transcription, providing a means to analyze these two key features of FOXO regulation in the same experiment. We challenged the U2transLUC system with chemical probes with known biological activities and we were able to identify compounds with translocation and/or transactivation capacity. Conclusion Combining different biological read-outs in a single cell line offers significant advantages over conventional cell-based assays. The U2transLUC assay facilitates the maintenance and monitoring of homogeneous FOXO transcription factor expression and allows the reporter gene activity measured to be normalized with respect to cell viability. U2transLUC is suitable for high throughput screening and can identify small molecules that interfere with FOXO signaling at different levels.

  12. Two-photon microscopy imaging of thy1GFP-M transgenic mice: a novel animal model to investigate brain dendritic cell subsets in vivo.

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    Claudia Laperchia

    Full Text Available Transgenic mice expressing fluorescent proteins in specific cell populations are widely used for in vivo brain studies with two-photon fluorescence (TPF microscopy. Mice of the thy1GFP-M line have been engineered for selective expression of green fluorescent protein (GFP in neuronal populations. Here, we report that TPF microscopy reveals, at the brain surface of these mice, also motile non-neuronal GFP+ cells. We have analyzed the behavior of these cells in vivo and characterized in brain sections their immunophenotype.With TPF imaging, motile GFP+ cells were found in the meninges, subarachnoid space and upper cortical layers. The striking feature of these cells was their ability to move across the brain parenchyma, exhibiting evident shape changes during their scanning-like motion. In brain sections, GFP+ cells were immunonegative to antigens recognizing motile cells such as migratory neuroblasts, neuronal and glial precursors, mast cells, and fibroblasts. GFP+ non-neuronal cells exhibited instead the characteristic features and immunophenotype (CD11c and major histocompatibility complex molecule class II immunopositivity of dendritic cells (DCs, and were immunonegative to the microglial marker Iba-1. GFP+ cells were also identified in lymph nodes and blood of thy1GFP-M mice, supporting their identity as DCs. Thus, TPF microscopy has here allowed the visualization for the first time of the motile behavior of brain DCs in situ. The results indicate that the thy1GFP-M mouse line provides a novel animal model for the study of subsets of these professional antigen-presenting cells in the brain. Information on brain DCs is still very limited and imaging in thy1GFP-M mice has a great potential for analyses of DC-neuron interaction in normal and pathological conditions.

  13. Engraftment of retrovirally transduced Bet v 1-GFP expressing bone marrow cells leads to allergen-specific tolerance.

    Science.gov (United States)

    Gattringer, Martina; Baranyi, Ulrike; Pilat, Nina; Hock, Karin; Klaus, Christoph; Buchberger, Elisabeth; Ramsey, Haley; Iacomini, John; Valenta, Rudolf; Wekerle, Thomas

    2013-09-01

    Molecular chimerism is a promising strategy to induce tolerance to disease-causing antigens expressed on genetically modified haematopoietic stem cells. The approach was employed successfully in models of autoimmunity and organ transplantation. Recently, we demonstrated that molecular chimerism induces robust and lasting tolerance towards the major grass pollen allergen Phl p 5. Since allergens are a group of antigens differing widely in their function, origin and structure we further examined the effectiveness of molecular chimerism using the Phl p 5-unrelated major birch pollen allergen Bet v 1, co-expressed with the reporter GFP. Besides, inhibition of CD26 was used to promote engraftment of modified stem cells. Retrovirus VSV-Betv1-GFP was generated to transduce 5-FU-mobilized BALB/c hematopoietic cells to express membrane-bound Bet v 1 (VSV-GFP virus was used as control). Myeloablated BALB/c mice received Betv1-GFP or GFP expressing bone marrow cells, pre-treated with a CD26 inhibitor. Chimerism was followed by flow cytometry. Tolerance was assessed by measuring allergen-specific isotype levels in sera, RBL assays and T-cell proliferation assays. Mice transplanted with transduced BMC developed multi-lineage molecular chimerism which remained stable long-term (>8 months). After repeated immunizations with Bet v 1 and Phl p 5 serum levels of Bet v 1-specific antibodies (IgE, IgG1, IgG2a, IgG3 and IgA) remained undetectable in Betv1-GFP chimeras while high levels of Phl p 5-specific antibodies developed. Likewise, basophil degranulation was induced in response to Phl p 5 but not to Bet v 1 and specific non-responsiveness to Bet v 1 was observed in proliferation assays. These data demonstrate successful tolerization towards Bet v 1 by molecular chimerism. Stable long-term chimerism was achieved under inhibition of CD26. These results provide evidence for the broad applicability of molecular chimerism as tolerance strategy in allergy.

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

    Science.gov (United States)

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

    2001-01-01

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

  15. Nr4a1-eGFP is a marker of striosome-matrix architecture, development and activity in the extended striatum.

    Directory of Open Access Journals (Sweden)

    Margaret I Davis

    Full Text Available Transgenic mice expressing eGFP under population specific promoters are widely used in neuroscience to identify specific subsets of neurons in situ and as sensors of neuronal activity in vivo. Mice expressing eGFP from a bacterial artificial chromosome under the Nr4a1 promoter have high expression within the basal ganglia, particularly within the striosome compartments and striatal-like regions of the extended amygdala (bed nucleus of the stria terminalis, striatal fundus, central amygdaloid nucleus and intercalated cells. Grossly, eGFP expression is inverse to the matrix marker calbindin 28K and overlaps with mu-opioid receptor immunoreactivity in the striatum. This pattern of expression is similar to Drd1, but not Drd2, dopamine receptor driven eGFP expression in structures targeted by medium spiny neuron afferents. Striosomal expression is strong developmentally where Nr4a1-eGFP expression overlaps with Drd1, TrkB, tyrosine hydroxylase and phospho-ERK, but not phospho-CREB, immunoreactivity in "dopamine islands". Exposure of adolescent mice to methylphenidate resulted in an increase in eGFP in both compartments in the dorsolateral striatum but eGFP expression remained brighter in the striosomes. To address the role of activity in Nr4a1-eGFP expression, primary striatal cultures were prepared from neonatal mice and treated with forskolin, BDNF, SKF-83822 or high extracellular potassium and eGFP was measured fluorometrically in lysates. eGFP was induced in both neurons and contaminating glia in response to forskolin but SKF-83822, brain derived neurotrophic factor and depolarization increased eGFP in neuronal-like cells selectively. High levels of eGFP were primarily associated with Drd1+ neurons in vitro detected by immunofluorescence; however ∼15% of the brightly expressing cells contained punctate met-enkephalin immunoreactivity. The Nr4a1-GFP mouse strain will be a useful model for examining the connectivity, physiology, activity and

  16. Chromophore photophysics and dynamics in fluorescent proteins of the GFP family

    Science.gov (United States)

    Nienhaus, Karin; Nienhaus, G. Ulrich

    2016-11-01

    Proteins of the green fluorescent protein (GFP) family are indispensable for fluorescence imaging experiments in the life sciences, particularly of living specimens. Their essential role as genetically encoded fluorescence markers has motivated many researchers over the last 20 years to further advance and optimize these proteins by using protein engineering. Amino acids can be exchanged by site-specific mutagenesis, starting with naturally occurring proteins as templates. Optical properties of the fluorescent chromophore are strongly tuned by the surrounding protein environment, and a targeted modification of chromophore-protein interactions requires a profound knowledge of the underlying photophysics and photochemistry, which has by now been well established from a large number of structural and spectroscopic experiments and molecular-mechanical and quantum-mechanical computations on many variants of fluorescent proteins. Nevertheless, such rational engineering often does not meet with success and thus is complemented by random mutagenesis and selection based on the optical properties. In this topical review, we present an overview of the key structural and spectroscopic properties of fluorescent proteins. We address protein-chromophore interactions that govern ground state optical properties as well as processes occurring in the electronically excited state. Special emphasis is placed on photoactivation of fluorescent proteins. These light-induced reactions result in large structural changes that drastically alter the fluorescence properties of the protein, which enables some of the most exciting applications, including single particle tracking, pulse chase imaging and super-resolution imaging. We also present a few examples of fluorescent protein application in live-cell imaging experiments.

  17. Looking at the Green Fluorescent Protein (GFP) chromophore from a different perspective: a computational insight.

    Science.gov (United States)

    Paul, Bijan Kumar; Guchhait, Nikhil

    2013-02-15

    In the present contribution Density Functional Theory (DFT) has been applied to explore molecular dipole moment, frontier molecular orbital (FMO) features, chemical hardness, and the molecular electrostatic potential surface (MEPS) characteristics for optimized molecular geometry of the Green Fluorescent Protein (GFP) chromophore p-hydroxybenzylideneimidazolinone (HBDI) both in its protonated (neutral) and deprotonated (anion) forms. The distribution of atomic charges over the entire molecular framework as obtained from Natural Bond Orbital (NBO) analysis is found to faithfully replicate the predictions from the MEP map in respect of reactivity map of HBDI (neutral and anion) and possible sites for hydrogen bonding interactions etc. The three dimensional MEP map encompassing the entire molecule yields a reliable reactivity map of HBDI molecule also displaying the most probable regions for non-covalent interactions. The differential distribution of the electrostatic potential over the neutral and anionic species of HBDI is authentically reflected on MEP map and NBO charge distribution analysis. Thermodynamic properties such as heat capacity, thermal energy, enthalpy, entropy have been calculated and the correlation of the various thermodynamic functions with temperature has been established for neutral molecule. More importantly, however, the computational approach has been employed to unveil the nonlinear optical (NLO) properties of protonated (neutral) and deprotonated (anion) HBDI. Also in an endeavor to achieve a fuller understanding on this aspect the effect of basis set on the NLO properties of the title molecule has been investigated. Our computations delineate the discernible differences in NLO properties between the neutral and anionic species of HBDI whereby indicating the possibility of development of photoswitchable NLO device.

  18. Metallization and investigation of electrical properties of in vitro recrystallized mSbsC-eGFP assemblies

    Energy Technology Data Exchange (ETDEWEB)

    Korkmaz, Nuriye; Roedel, Gerhard [Institut fuer Genetik, Technische Universitaet Dresden, 01217 Dresden (Germany); Boerrnert, Felix; Mendes, Rafael G; Bachmatiuk, Alicja; Ruemmeli, Mark H; Buechner, Bernd [Leibniz-Institut fuer Festkoerper- und Werkstoffforschung Dresden, 01069 Dresden (Germany); Koehler, Denny; Eng, Lukas M, E-mail: korkmaz@yahoo.com, E-mail: f.boerrnert@ifw-dresden.de, E-mail: denny.koehler@iapp.de, E-mail: r.g.mendes@ifw-dresden.de, E-mail: a.bachmatiuk@ifw-dresden.de, E-mail: m.ruemmeli@ifw-dresden.de, E-mail: b.buechner@ifw-dresden.de, E-mail: lukas.eng@iapp.de, E-mail: gerhard.roedel@tu-dresden.de [Institut fuer Angewandte Photophysik, Technische Universitaet Dresden, 01062 Dresden (Germany)

    2011-09-16

    Surface layer (SL) proteins are self-assembling nanosized arrays which can be recrystallized in solution or on surfaces. In this paper, we investigate the metallization, contact potential difference and conductivity of in vitro recrystallized mSbsC-eGFP tube-like assemblies for possible applications in nanobiotechnology. Treatment of mSbsC-eGFP tube-like structures with 150 mM Pt salt solution resulted in the formation of metallized SL assemblies decorated with Pt nanoparticles (> 3 nm) which were closely packed and aggregated into metal clusters. Kelvin probe force microscopy (KPFM) measurements revealed that metallized and unmetallized SL templates showed different surface potential behaviours, demonstrating that the metal coating changes the electrostatic surface characteristics of SL assemblies. In situ conductivity measurements showed that unmetallized SL assemblies were not conductive. Metallized samples showed linear I-V dependence between - 1 and + 1 V with a conductivity of {approx} 10{sup 3} S m{sup -1}.

  19. Migration and Differentiation of GFP-transplanted Bone Marrow-derived Cells into Experimentally Induced Periodontal Polyp in Mice

    OpenAIRE

    MATSUDA, SAEKA; Shoumura, Masahito; Osuga, Naoto; Tsujigiwa, Hidetsugu; Nakano, Keisuke; Okafuji, Norimasa; OCHIAI, TAKANAGA; HASEGAWA, HIROMASA; Kawakami, Toshiyuki

    2016-01-01

    Perforation of floor of the dental pulp is often encountered during root canal treatment in routine clinical practice of dental caries. If perforation were large, granulation tissue would grow to form periodontal polyp. Granulation tissue consists of proliferating cells however their origin is not clear. It was shown that the cells in granulation tissue are mainly from migration of undifferentiated mesenchymal cells of the bone marrow. Hence, this study utilized GFP bone marrow transplantatio...

  20. The Subcellular Localization and Blue-Light-Induced Movement of Phototropin 1-GFP in Etiolated Seedlings of Arabidopsis thaliana

    Institute of Scientific and Technical Information of China (English)

    Ying-Lang Wan; William Eisinger; David Ehrhardt; Ulrich Kubitscheck; Frantisek Baluska; Winslow Briggs

    2008-01-01

    Phototropin 1 (phot1) is a photoreceptor for phototropism, chloroplast movement, stomatal opening, leaf expansion, and solar tracking in response to blue light. Following earlier work with PHOT1::GFP (Sakamoto and Briggs,2002), we investigated the pattern of cellular and subcellular localization of phot1 in 3-4 d old etiolated seedlings of Arabidopsis thalinana. As expressed from native upstream sequences, the PHOT1::GFP fusion protein is expressed strongly in the abaxial tissues of the cotyledons and in the elongating regions of the hypocotyl. It is moderately expressed in the shoot/root transition zone and in cells near the root apex. A fluorescence signal is undetectable in the root epidermis, root cap, and root apical meristem itself. The plasma membranes of mesophyll cells near the cotyledon margin appear labeled uniformly but cross-walls created by recent cell divisions are more strongly labeled. The pattern of labeling of individual cell types varies with cell type and developmental stage. Blue-light treatment causes PHOT1::GFP, initially relatively evenly distributed at the plasma membrane, to become reorganized into a distinct mosaic with strongly labeled punctate areas and other areas completely devoid of fluorescence-a phenomenon best observed in cortical cells in the hypocotyl elongation region. Concomitant with or following this reorganization, PHOT1::GFP moves into the cytoplasm in all cell types investigated except for guard cells. It disappears from the cytoplasm by an unidentified mechanism after several hours in darkness. Neither its appearance in the cytoplasm nor its eventual disappearance in darkness is prevented by the translation inhibitor cycloheximide, although the latter process is retarded. We hypothesize that blue-light-induced phot1 relocalization modulates blue-light-activated signal transduction.

  1. Fluorescent immortalized human adipose derived stromal cells (hASCs-TS/GFP+) for studying cell drug delivery mediated by microvesicles.

    Science.gov (United States)

    Coccè, Valentina; Balducci, Luigi; Falchetti, Maria Laura; Pascucci, Luisa; Ciusani, Emilio; Brini, Anna Teresa; Sisto, Francesca; Piovani, Giovanna; Alessandri, Giulio; Parati, Eugenio; Cabeza, Laura; Pessina, Augusto

    2017-03-27

    A new tool for the drug delivery is based on the use of Mesenchymal Stromal Cells (MSCs) loaded in vitro with anti-cancer drugs. Unfortunately, the restricted lifespan of MSCs represents a significant limitation to produce them in high amounts and for long time studies. Immortalized MSCs from adipose tissue (hASC) have been generated as good source of cells with stable features. These cells could improve the development of standardized procedures for both in vitro and preclinical studies. Furthermore they facilitate procedures for preparing large amounts of secretome containing microvesicles (MVs). We used human adipose tissue derived MSCs immortalized with hTERT+SV40 (TS) genes and transfected with GFP (hASCs-TS/GFP+). This line was investigate for its ability to uptake and release anticancer drugs. Microvesicles associated to paclitaxel (MVs/PTX) were isolated, quantified, and tested on pancreatic cancer cells. The line hASCs-TS/GFP+ maintained the main mesenchymal characters and was able to uptake and release, in active form, both paclitaxel and gemcitabine. From paclitaxel loaded hASCs-TS/GFP+ cells were isolated microvesicles in sufficient amount to inhibit "in vitro" the proliferation of pancreatic tumor cells. Our study suggests that human immortalized MSCs could be used for a large scale production of cells for mediated drug delivery. Moreover, the secretion of drug-associated MVs could represent a new way for producing new drug formulation by "biogenesis". In the context of the "advanced cell therapy procedure", the MVs/PTX production would be less resource and time consuming and it could possibly contribute to simplification of GMP procedures. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  2. Fluorescent labeling of newborn dentate granule cells in GAD67-GFP transgenic mice: a genetic tool for the study of adult neurogenesis.

    Directory of Open Access Journals (Sweden)

    Shengli Zhao

    Full Text Available Neurogenesis in the adult hippocampus is an important form of structural plasticity in the brain. Here we report a line of BAC transgenic mice (GAD67-GFP mice that selectively and transitorily express GFP in newborn dentate granule cells of the adult hippocampus. These GFP(+ cells show a high degree of colocalization with BrdU-labeled nuclei one week after BrdU injection and express the newborn neuron marker doublecortin and PSA-NCAM. Compared to mature dentate granule cells, these newborn neurons show immature morphological features: dendritic beading, fewer dendritic branches and spines. These GFP(+ newborn neurons also show immature electrophysiological properties: higher input resistance, more depolarized resting membrane potentials, small and non-typical action potentials. The bright labeling of newborn neurons with GFP makes it possible to visualize the details of dendrites, which reach the outer edge of the molecular layer, and their axon (mossy fiber terminals, which project to the CA3 region where they form synaptic boutons. GFP expression covers the whole developmental stage of newborn neurons, beginning within the first week of cell division and disappearing as newborn neurons mature, about 4 weeks postmitotic. Thus, the GAD67-GFP transgenic mice provide a useful genetic tool for studying the development and regulation of newborn dentate granule cells.

  3. Human pluripotent stem cell derived midbrain PITX3eGFP/w neurons: a versatile tool for pharmacological screening and neurodegenerative modelling

    Directory of Open Access Journals (Sweden)

    Bradley eWatmuff

    2015-03-01

    Full Text Available AbstractPITX3 expression is confined to adult midbrain dopaminergic neurons. In this study we describe the generation and basic functional characteristics of midbrain dopaminergic neurons derived from a human pluripotent stem cell line expressing eGFP under the control of the PITX3 promoter. Flow cytometry shows that eGFP is evident in 15% of the neuron population at day 12 of differentiation and this level is maintained until at least day 80. From day 20-80 of differentiation intracellular chloride decreases and throughout this period around ~20% of PITX3eGFP/w neurons exhibit spontaneous Ca2+ transients (from 3.3+/-0.3 to 5.0+/-0.1 min-1, respectively. These neurons also respond to any of ATP, glutamate, acetylcholine or noradrenaline with elevations of intracellular calcium. As neuronal cultures mature more dopamine is released and single PITX3eGFP/w neurons begin to respond to more than one neurotransmitter. MPP+ and tumor necrosis factor(TNF, but not prostaglandin E2, caused death of the ~50% of PITX3eGFP/w neurons (day 80. Tracking eGFP using time lapse confocal microscopy over 24 hours demonstrated significant TNF-mediated neurite retraction over time. These PITX3eGFP/w neurons are amenable to flow cytometry, release dopamine and respond to multiple neurotransmitters with elevations of intracellular calcium, we believe that they represent a versatile system for neuropharmacological and neurotoxicological studies.

  4. Plasmid Stability in Dried Cells of the Desert Cyanobacterium Chroococcidiopsis and its Potential for GFP Imaging of Survivors on Earth and in Space

    Science.gov (United States)

    Billi, Daniela

    2012-06-01

    Two GFP-based plasmids, namely pTTQ18-GFP-pDU1mini and pDUCA7-GFP, of about 7 kbp and 15 kbp respectively, able to replicate in Chroococcidiopsis sp. CCMEE 029 and CCMEE 123, were developed. Both plasmids were maintained in Chroococcidiopsis cells after 18 months of dry storage as demonstrated by colony PCR, plasmid restriction analysis, GFP imaging and colony-forming ability under selection of dried transformants; thus suggesting that strategies employed by this cyanobacterium to stabilize dried chromosomal DNA, must have protected plasmid DNA. The suitability of pDU1mini-plasmid for GFP tagging in Chroococcidiopsis was investigated by using the RecA homolog of Synechocystis sp. PCC 6803. After 2 months of dry storage, the presence of dried cells with a GFP-RecASyn distribution resembling that of hydrated cells, supported its capability of preventing desiccation-induced genome damage, whereas the rewetted cells with filamentous GFP-RecASyn structures revealed sub-lethal DNA damage. The long-term stability of plasmid DNA in dried Chroococcidiopsis has implication for space research, for example when investigating the recovery of dried cells after Martian and space simulations or when developing life support systems based on phototrophs with genetically enhanced stress tolerance and stored in the dry state for prolonged periods.

  5. EVALUACIÓN COMPORTAMENTAL DEL TRASPLANTE DE hMSC-GFP+ EN UN MODELO EXPERIMENTAL DE HEMIPARKINSON EN RATA WISTAR

    Directory of Open Access Journals (Sweden)

    Jéssica Paola ALCÁZAR ARZUZA

    2017-01-01

    Full Text Available Se evaluó el efecto del trasplante de hMSC-GFP+ en un modelo experimental de Enfermedad de Parkinson (EP en 27 ratas Wistar con tres grupos experimentales: control: animales sin cirugía, (CON n=7, lesionado: animales lesionados intracerebralmente con 6-OHDA a nivel de SNpc (LES n=10 y trasplantado: animales LES con trasplante de hMSC-GFP+ intraestriatalmente (LES-T n=10. Con el fin de evaluar la influencia del trasplante en el comportamiento motor, un mes después de la lesión, se desarrolló una batería comportamental compuesta por Test Neurológico (compuesto también por Pole Test y Test de Barra transversal, además, de inmunofluorescencia para células de SNpc con TH. Utilizando el test de Anova, se demostró una disminución en el número de giros en animales trasplantados ( p =0,005 , así como en el test neurológico ( p =0,0004 y en el Test de barra transversal, que colocan a este grupo en una posición intermedia con respecto a LES y CON. Existe una posible recuperación de la vía nigroestriatal mediada por el trasplante de hMSC-GFP+.

  6. A faster way to make GFP-based biosensors: Two new transposons for creating multicolored libraries of fluorescent fusion proteins

    Directory of Open Access Journals (Sweden)

    Hughes Thomas E

    2004-08-01

    Full Text Available Abstract Background There are now several ways to generate fluorescent fusion proteins by randomly inserting DNA encoding the Green Fluorescent Protein (GFP into another protein's coding sequence. These approaches can be used to map regions in a protein that are permissive for GFP insertion or to create novel biosensors. While remarkably useful, the current insertional strategies have two major limitations: (1 they only produce one kind, or color, of fluorescent fusion protein and (2 one half of all GFP insertions within the target coding sequence are in the wrong orientation. Results We have overcome these limitations by incorporating two different fluorescent proteins coding sequences in a single transposon, either in tandem or antiparallel. Our initial tests targeted two mammalian integral membrane proteins: the voltage sensitive motor, Prestin, and an ER ligand gated Ca2+ channel (IP3R. Conclusions These new designs increase the efficiency of random fusion protein generation in one of two ways: (1 by creating two different fusion proteins from each insertion or (2 by being independent of orientation.

  7. Correlative and integrated light and electron microscopy of in-resin GFP fluorescence, used to localise diacylglycerol in mammalian cells.

    Science.gov (United States)

    Peddie, Christopher J; Blight, Ken; Wilson, Emma; Melia, Charlotte; Marrison, Jo; Carzaniga, Raffaella; Domart, Marie-Charlotte; O'Toole, Peter; Larijani, Banafshe; Collinson, Lucy M

    2014-08-01

    Fluorescence microscopy of GFP-tagged proteins is a fundamental tool in cell biology, but without seeing the structure of the surrounding cellular space, functional information can be lost. Here we present a protocol that preserves GFP and mCherry fluorescence in mammalian cells embedded in resin with electron contrast to reveal cellular ultrastructure. Ultrathin in-resin fluorescence (IRF) sections were imaged simultaneously for fluorescence and electron signals in an integrated light and scanning electron microscope. We show, for the first time, that GFP is stable and active in resin sections in vacuo. We applied our protocol to study the subcellular localisation of diacylglycerol (DAG), a modulator of membrane morphology and membrane dynamics in nuclear envelope assembly. We show that DAG is localised to the nuclear envelope, nucleoplasmic reticulum and curved tips of the Golgi apparatus. With these developments, we demonstrate that integrated imaging is maturing into a powerful tool for accurate molecular localisation to structure. Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.

  8. A GFP-based bacterial biosensor with chromosomally integrated sensing cassette for quantitative detection of Hg(II) in environment

    Institute of Scientific and Technical Information of China (English)

    Himanshu Priyadarshi; Absar Alam; Gireesh-Babu P; Rekha Das; Pankaj Kishore; Shivendra Kumar; Aparna Chaudhari

    2012-01-01

    A mercury biosensor was constructed by integrating biosensor genetic elements into E.coli JM109 chromosome in a single copy number,using the attP/attB recombination mechanism of λ phage.The genetic elements used include a regulatory protein gene (merR) along with operator/promoter (O/P) derived from the mercury resistance operon from pDU1358 plasmid of Serratia marcescens.The expression of reporter gene gfp is also controlled by merR/O/P.Integration of the construct into the chromosome was done to increase the stability and precision of the biosensor.This biosensor could detect Hg(Ⅱ) ions in the concentration range of 100-1700 mnol/L,and manifest the result as the expression of GFP.The GFP expression was significantly different (P ≤ 0.05) for each concentration of inducing Hg(Ⅱ) ions in the detection range,which reduces the chances of misinterpretation of results.A model using regression method was also derived for the quantification of the concentration of Hg(Ⅱ) in water samples.

  9. Analysis of 75 marketed pharmaceuticals using the GADD45a-GFP 'GreenScreen HC' genotoxicity assay.

    Science.gov (United States)

    Hastwell, Paul W; Webster, Thomas W; Tate, Matthew; Billinton, Nicholas; Lynch, Anthony M; Harvey, James S; Rees, Robert W; Walmsley, Richard M

    2009-09-01

    The GADD45a-GFP (GreenScreen HC) reporter assay detects genotoxic damage in the human lymphoblastoid TK6 cell line and gives positive results for all classes of genotoxin, including mutagens, aneugens and clastogens. In this study, a collection of 75 marketed pharmaceuticals were tested in the assay. Compounds in the collection represent a broad range of chemical structures, pharmacologies and therapeutic indications, including neoplasia and viral infection where positive genotoxicity results are often associated with the pharmacological activity. Based on the results of this study, two main conclusions can be drawn: (i) the GreenScreen HC is more predictive of in vivo genotoxicity (88%) and genotoxic carcinogenicity (93%) data than the any of the other regulatory in vitro genotoxicity assay and (ii) no compounds were uniquely positive in the GADD45a-GFP assay. This analysis therefore provides additional evidence to support the use of the GADD45a-GFP assay as an effective tool either in early genotoxic liability identification or non-clinical safety assessment of candidate pharmaceuticals during development.

  10. Measuring E(GSH) and H2O2 with roGFP2-based redox probes.

    Science.gov (United States)

    Morgan, Bruce; Sobotta, Mirko C; Dick, Tobias P

    2011-12-01

    Redox biochemistry plays an important role in a wide range of cellular events. However, investigation of cellular redox processes is complicated by the large number of cellular redox couples, which are often not in equilibrium with one another and can vary significantly between subcellular compartments and cell types. Further, it is becoming increasingly clear that different redox systems convey different biological information; thus it makes little sense to talk of an overall "cellular redox state". To gain a more differentiated understanding of cellular redox biology, quantitative, redox couple-specific, in vivo measurements are necessary. Unfortunately our ability to investigate specific redox couples or redox-reactive molecules with the necessary degree of spatiotemporal resolution is very limited. The development of genetically encoded redox biosensors offers a promising new way to investigate redox biology. Recently developed redox-sensitive green fluorescent proteins (roGFPs), genetically fused to redox-active proteins, allow rapid equilibration of the roGFP moiety with a specific redox couple. Two probes based on this principle are now available: Grx1-roGFP2 for the measurement of glutathione redox potential (E(GSH)) and roGFP2-Orp1 for measuring changes in H(2)O(2) concentration. Here we provide a detailed protocol for the use of these probes in both yeast and mammalian systems using either plate-reader- or microscopy-based measurements. Copyright © 2011 Elsevier Inc. All rights reserved.

  11. Construction and use of a Cupriavidus necator H16 soluble hydrogenase promoter (PSH) fusion to gfp (green fluorescent protein).

    Science.gov (United States)

    Jugder, Bat-Erdene; Welch, Jeffrey; Braidy, Nady; Marquis, Christopher P

    2016-01-01

    Hydrogenases are metalloenzymes that reversibly catalyse the oxidation or production of molecular hydrogen (H2). Amongst a number of promising candidates for application in the oxidation of H2 is a soluble [Ni-Fe] uptake hydrogenase (SH) produced by Cupriavidus necator H16. In the present study, molecular characterisation of the SH operon, responsible for functional SH synthesis, was investigated by developing a green fluorescent protein (GFP) reporter system to characterise PSH promoter activity using several gene cloning approaches. A PSH promoter-gfp fusion was successfully constructed and inducible GFP expression driven by the PSH promoter under de-repressing conditions in heterotrophic growth media was demonstrated in the recombinant C. necator H16 cells. Here we report the first successful fluorescent reporter system to study PSH promoter activity in C. necator H16. The fusion construct allowed for the design of a simple screening assay to evaluate PSH activity. Furthermore, the constructed reporter system can serve as a model to develop a rapid fluorescent based reporter for subsequent small-scale process optimisation experiments for SH expression.

  12. Construction and use of a Cupriavidus necator H16 soluble hydrogenase promoter (PSH fusion to gfp (green fluorescent protein

    Directory of Open Access Journals (Sweden)

    Bat-Erdene Jugder

    2016-07-01

    Full Text Available Hydrogenases are metalloenzymes that reversibly catalyse the oxidation or production of molecular hydrogen (H2. Amongst a number of promising candidates for application in the oxidation of H2 is a soluble [Ni–Fe] uptake hydrogenase (SH produced by Cupriavidus necator H16. In the present study, molecular characterisation of the SH operon, responsible for functional SH synthesis, was investigated by developing a green fluorescent protein (GFP reporter system to characterise PSH promoter activity using several gene cloning approaches. A PSH promoter-gfp fusion was successfully constructed and inducible GFP expression driven by the PSH promoter under de-repressing conditions in heterotrophic growth media was demonstrated in the recombinant C. necator H16 cells. Here we report the first successful fluorescent reporter system to study PSH promoter activity in C. necator H16. The fusion construct allowed for the design of a simple screening assay to evaluate PSH activity. Furthermore, the constructed reporter system can serve as a model to develop a rapid fluorescent based reporter for subsequent small-scale process optimisation experiments for SH expression.

  13. Construction of HeLa/GFP-Plk1/Cherry-H2B Cells%HeLa/GFP-Plk1/Cherry-H2B稳定细胞系的构建

    Institute of Scientific and Technical Information of China (English)

    李伟; 胥全彬; 江其生; 刘萱; 李平; 曹诚

    2014-01-01

    Objective: To construct HeLa cells available for study of localization of Polo-like kinase1(Plk1). Methods: Plk1 gene was amplified by PCR and then inserted into vector pRex-EGFP-IRES-Hygro to construct pRex-EGFP-Plk1-IRES-Hygro plasmid. Through retroviral infection, the pRex-EGFP-Plk1-IRES-Hygro and pRex-Cherry-H2B-IRES-Hygro plasmids were transfected into HeLa cells in turn to construct HeLa/GFP-Plk1/Cherry-H2B stable cells. The localization of Plk1 in different mitotic phase was observed under confocal laser scanning microscope. Results: The vector pRex-EGFP-Plk1-IRES-Hygro was verified by enzyme digestion and sequencing. In constructed HeLa/GFP-Plk1/Cherry-H2B stable cells, Plk1 was observed in kinetochores and midbody respective-ly in metaphase and telophase. Conclusion: The constructed HeLa/GFP-Plk1/Cherry-H2B stable cells will benefit the further research on the regulation mechanism of Plk1 in mitosis.%目的:构建可研究Polo样激酶1(Plk1)定位的HeLa细胞系。方法:用PCR方法扩增Plk1基因,定向克隆到pRex-EGFP-IRES-Hygro载体中,构建pRex-EGFP-Plk1-IRES-Hygro表达载体;利用逆转录病毒感染的方法,向HeLa细胞系中依次转染pRex-EGFP-Plk1-IRES-Hygro、pRex-Cherry-H2B-IRES-Hygro,构建Hela/GFP-Plk1/Cher-ry-H2B稳定细胞系;激光共聚焦显微镜观察Hela/GFP-Plk1/Cherry-H2B稳定细胞系在不同有丝细胞分裂期时Plk1的定位。结果:质粒酶切及测序证明pRex-EGFP-Plk1-IRES-Hygro载体构建正确;在Hela/GFP-Plk1/Cherry-H2B稳定细胞系有丝分裂中期和末期时,观察到Plk1分别定位于着丝粒和中间体上。结论:构建了Hela/GFP-Plk1/Cherry-H2B稳定细胞系,为研究Plk1在有丝分裂不同时期的调控机制提供了细胞模型。

  14. Identifying interacting proteins of a Caenorhabditis elegans voltage-gated chloride channel CLH-1 using GFP-Trap and mass spectrometry.

    Science.gov (United States)

    Zhou, Zi-Liang; Jiang, Jing; Yin, Jiang-An; Cai, Shi-Qing

    2014-06-25

    Chloride channels belong to a superfamily of ion channels that permit passive passage of anions, mainly chloride, across cell membrane. They play a variety of important physiological roles in regulation of cytosolic pH, cell volume homeostasis, organic solute transport, cell migration, cell proliferation, and differentiation. However, little is known about the functional regulation of these channels. In this study, we generated an integrated transgenic worm strain expressing green fluorescence protein (GFP) fused CLC-type chloride channel 1 (CLH-1::GFP), a voltage-gated chloride channel in Caenorhabditis elegans (C. elegans). CLH-1::GFP was expressed in some unidentified head neurons and posterior intestinal cells of C. elegans. Interacting proteins of CLH-1::GFP were purified by GFP-Trap, a novel system for efficient isolation of GFP fusion proteins and their interacting factors. Mass spectrometry (MS) analysis revealed that a total of 27 high probability interacting proteins were co-trapped with CLHp-1::GFP. Biochemical evidence showed that eukaryotic translation elongation factor 1 (EEF-1), one of these co-trapped proteins identified by MS, physically interacted with CLH-1, in consistent with GFP-Trap experiments. Further immunostaining data revealed that the protein level of CLH-1 was significantly increased upon co-expression with EEF-1. These results suggest that the combination of GFP-Trap purification with MS is an excellent tool to identify novel interacting proteins of voltage-gated chloride channels in C. elegans. Our data also show that EEF-1 is a regulator of voltage-gated chloride channel CLH-1.

  15. Medial prefrontal cortex neuronal activation and synaptic alterations after stress-induced reinstatement of palatable food seeking: a study using c-fos-GFP transgenic female rats

    OpenAIRE

    2012-01-01

    Relapse to maladaptive eating habits during dieting is often provoked by stress and there is evidence for a role of ovarian hormones in stress responses and feeding. We studied the role of these hormones in stress-induced reinstatement of food seeking and medial prefrontal cortex (mPFC) neuronal activation in c-fos-GFP transgenic female rats, which express green fluorescent protein (GFP) in strongly activated neurons. Food-restricted ovariectomized or sham-operated c-fos-GFP rats were trained...

  16. Green fluorescent protein (GFP color reporter gene visualizes parvovirus B19 non-structural segment 1 (NS1 transfected endothelial modification.

    Directory of Open Access Journals (Sweden)

    Thomas Wurster

    Full Text Available BACKGROUND: Human Parvovirus B19 (PVB19 has been associated with myocarditis putative due to endothelial infection. Whether PVB19 infects endothelial cells and causes a modification of endothelial function and inflammation and, thus, disturbance of microcirculation has not been elucidated and could not be visualized so far. METHODS AND FINDINGS: To examine the PVB19-induced endothelial modification, we used green fluorescent protein (GFP color reporter gene in the non-structural segment 1 (NS1 of PVB19. NS1-GFP-PVB19 or GFP plasmid as control were transfected in an endothelial-like cell line (ECV304. The endothelial surface expression of intercellular-adhesion molecule-1 (CD54/ICAM-1 and extracellular matrix metalloproteinase inducer (EMMPRIN/CD147 were evaluated by flow cytometry after NS-1-GFP or control-GFP transfection. To evaluate platelet adhesion on NS-1 transfected ECs, we performed a dynamic adhesion assay (flow chamber. NS-1 transfection causes endothelial activation and enhanced expression of ICAM-1 (CD54: mean ± standard deviation: NS1-GFP vs. control-GFP: 85.3 ± 11.2 vs. 61.6 ± 8.1; P<0.05 and induces endothelial expression of EMMPRIN/CD147 (CD147: mean ± SEM: NS1-GFP vs. control-GFP: 114 ± 15.3 vs. 80 ± 0.91; P<0.05 compared to control-GFP transfected cells. Dynamic adhesion assays showed that adhesion of platelets is significantly enhanced on NS1 transfected ECs when compared to control-GFP (P<0.05. The transfection of ECs was verified simultaneously through flow cytometry, immunofluorescence microscopy and polymerase chain reaction (PCR analysis. CONCLUSIONS: GFP color reporter gene shows transfection of ECs and may help to visualize NS1-PVB19 induced endothelial activation and platelet adhesion as well as an enhanced monocyte adhesion directly, providing in vitro evidence of possible microcirculatory dysfunction in PVB19-induced myocarditis and, thus, myocardial tissue damage.

  17. Transgenic (cyp19a1b-GFP) zebrafish embryos as a tool for assessing combined effects of oestrogenic chemicals.

    Science.gov (United States)

    Petersen, Karina; Fetter, Eva; Kah, Olivier; Brion, François; Scholz, Stefan; Tollefsen, Knut Erik

    2013-08-15

    Endocrine disrupting chemicals and especially oestrogen receptor (ER) agonists have been extensively studied over the years due to their potential effects on sexual development and reproduction in vertebrates, notably fish. As ER agonists can exist as complex mixtures in the aquatic environment, evaluating the impact of combined exposure on oestrogenic effects has become increasingly important. Use of predictive models such as concentration addition (CA) and independent action (IA) has allowed assessment of combined estrogenic effects of complex multi-compound mixtures of ER agonists in various fish in vitro and in vivo experimental models. The present work makes use of a transgenic zebrafish strain, tg(cyp19a1b-GFP), which expresses the green fluorescent protein (GFP) under the control of the cyp19a1b (brain aromatase or aromatase B) gene to determine the oestrogenic potency of ER agonists alone or in mixtures. In these studies, tg(cyp19a1b-GFP) zebrafish embryos were exposed for four days (from one to five days post fertilization) to five different oestrogenic chemicals; 17α-ethinylestradiol (EE2), 17β-estradiol (E2), estrone (E1), bisphenol A (BPA) and 4-tert-octylphenol (OP), and three mixtures of up to four of these compounds. The mixture of BPA, OP and E2 was also tested with primary cultures of rainbow trout hepatocytes by analysing the ER-mediated induction of the oestrogenic biomarker vitellogenin in order to compare the performance of the two methods for assessing oestrogenic effects of complex mixtures. The three tested mixtures were predominantly acting in an additive manner on the expression of GFP. Additivity was indicated by the overlap of the 95% confidence interval of the concentration response curves for the observed data with the CA and IA prediction models, and model deviation ratios within a factor of two for a majority of the mixture concentrations. However, minor deviations determined as more than additive effects for the mixture of EE2, E1

  18. Genetic transformation of Drosophila willistoni using piggyBac transposon and GFP

    Directory of Open Access Journals (Sweden)

    Manuela Finokiet

    2007-01-01

    Full Text Available Studies were carried out on the use of piggyBac transposable element as vector and the green fluorescent protein (EGFP from the jellyfish, Aquorea victoria, as a genetic marker for the transformation of Drosophila willistoni. Preblastoderm embryos of D. willistoni white mutant were microinjected with a plasmid containing the EGFP marker and the piggyBac ITRs, together with a helper plasmid containing the piggyBac transposase placed under the control of the D. melanogaster hsp70 promoter. G0 adults transformants were recovered at a frequency of approximately 67%. Expression of EGFP in larvae, pupae and adults was observed up to the third generation, suggesting that this transposon was not stable in D. willistoni. Transformed individuals displayed high levels of EGFP expression during larvae and adult stages in the eye, abdomen, thorax and legs, suggesting a wide expression pattern in this species than reported to other species of Drosophilidae.Descrevemos neste trabalho a transformação genética de Drosophila willistoni empregando o elemento transponível piggyBac como vetor e o gene EGFP (green fluorescent protein retirado da água-viva Aquorea victoria, como marcador de transformação. Embriões de D. willistoni em estágio pré-blastoderme, mutantes para o gene white, foram microinjetados com plasmídio contendo o marcador EGFP e as regiões ITRs do transposon piggyBac concomitantemente com um plasmídio auxiliar possuindo o gene da transposase de piggyBac sobre o controle do promotor do gene hsp70 de Drosophila melanogaster. Adultos transformantes Go foram gerados em uma taxa de 67%. A expressão de GFP em larvas, pupas e adultos foi observada somente até a terceira geração, sugerindo que este transposon não é estável em D. willistoni. Os indivíduos transformados exigem um alto nível de expressão de EGFP durante os estágios de larva e, também em adultos o gene marcador é expresso nos olhos, abdome, tórax e patas, mostrando um

  19. ?????????? ?????????? ????????? ? ???????

    OpenAIRE

    2015-01-01

    ??????????? ?????? ?????????? ????????? ? ?????. ??????????? ???????? ???? ???????? ?????????? ????????? ? ???????. ?????????????? ??????? ??????? ?? ??????????? ?????????? (???????? GFP). ?????????? ?????????? ?????????? ????? ????????????? ?? ????????? ???? ???????, ????? ?? ???????? ?????????? ????????? ? ???????, ????? ?? ????????. ?????????????? ??????? ???????, ??? ? ????? ?????????? ?????????? ??????????. ???????? ??????? ??????? ??????, ??? ????????? ?? ???????? ? ???????? ????? ?????...

  20. Generation of a Stable Transgenic Swine Model Expressing a Porcine Histone 2B-eGFP Fusion Protein for Cell Tracking and Chromosome Dynamics Studies

    Science.gov (United States)

    Simpson, Sean; Collins, Bruce; Sommer, Jeff; Petters, Robert M.; Caballero, Ignacio; Platt, Jeff L.

    2017-01-01

    Transgenic pigs have become an attractive research model in the field of translational research, regenerative medicine, and stem cell therapy due to their anatomic, genetic and physiological similarities with humans. The development of fluorescent proteins as molecular tags has allowed investigators to track cell migration and engraftment levels after transplantation. Here we describe the development of two transgenic pig models via SCNT expressing a fusion protein composed of eGFP and porcine Histone 2B (pH2B). This fusion protein is targeted to the nucleosomes resulting a nuclear/chromatin eGFP signal. The first model (I) was generated via random insertion of pH2B-eGFP driven by the CAG promoter (chicken beta actin promoter and rabbit Globin poly A; pCAG-pH2B-eGFP) and protected by human interferon-β matrix attachment regions (MARs). Despite the consistent, high, and ubiquitous expression of the fusion protein pH2B-eGFP in all tissues analyzed, two independently generated Model I transgenic lines developed neurodegenerative symptoms including Wallerian degeneration between 3–5 months of age, requiring euthanasia. A second transgenic model (II) was developed via CRISPR-Cas9 mediated homology-directed repair (HDR) of IRES-pH2B-eGFP into the endogenous β-actin (ACTB) locus. Model II transgenic animals showed ubiquitous expression of pH2B-eGFP on all tissues analyzed. Unlike the pCAG-pH2B-eGFP/MAR line, all Model II animals were healthy and multiple pregnancies have been established with progeny showing the expected Mendelian ratio for the transmission of the pH2B-eGFP. Expression of pH2B-eGFP was used to examine the timing of the maternal to zygotic transition after IVF, and to examine chromosome segregation of SCNT embryos. To our knowledge this is the first viable transgenic pig model with chromatin-associated eGFP allowing both cell tracking and the study of chromatin dynamics in a large animal model. PMID:28081156

  1. Contrasting colonization and plant growth promoting capacity between wild type and gfp-derative of the endophyte Pseudomonas putida W619 in hybrid poplar

    Energy Technology Data Exchange (ETDEWEB)

    Weyens N.; van der Lelie D.; Boulet, J.; Adriaensen, D.; Timmermans, J.-P.; Prinsen, E.; Van Oevelen, S.; D" Haen, J.; Smeets, K.; Taghavi, S.; Vangronsveld, J.

    2011-06-09

    This study aims to investigate the colonization of poplar by the endophyte Pseudomonas putida W619 and its capacity to promote plant growth. Poplar cuttings were inoculated with P. putida W619 (wild-type or gfp-labelled). The colonization of both strains was investigated and morphological, physiological and biochemical parameters were analyzed to evaluate plant growth promotion. Inoculation with P. putida W619 (wild-type) resulted in remarkable growth promotion, decreased activities of antioxidative defence related enzymes, and reduced stomatal resistance, all indicative of improved plant health and growth in comparison with the non-inoculated cuttings. In contrast, inoculation with gfp-labelled P. putida W619 did not promote growth; it even had a negative effect on plant health and growth. Furthermore, compared to the wildtype strain, colonization by the gfp-labelled P. putida W619::gfp1 was much lower; it only colonized the rhizosphere and root cortex while the wild-type strain also colonized the root xylem vessels. Despite the strong plant growth promoting capacity of P. putida W619 (wild-type), after gfp labelling its growth promoting characteristics disappeared and its colonization capacity was strongly influenced; for these reasons gfp labelling should be applied with sufficient caution.

  2. Imaging long distance propagating calcium signals in intact plant leaves with the BRET-based GFP-Aequorin reporter

    Directory of Open Access Journals (Sweden)

    Tou Cheu eXiong

    2014-02-01

    Full Text Available Calcium (Ca2+ is a second messenger involved in many plant signalling processes. Biotic and abiotic stimuli induce Ca2+ signals within plant cells, which, when decoded, enable these cells to adapt in response to environmental stresses. Multiple examples of Ca2+ signals from plants containing the fluorescent yellow cameleon sensor (YC have contributed to the definition of the Ca2+ signature in some cell types such as root hairs, pollen tubes and guard cells. YC is, however, of limited use in highly autofluorescent plant tissues, in particular mesophyll cells. Alternatively, the bioluminescent reporter aequorin enables Ca2+ imaging in the whole plant, including mesophyll cells, but this requires specific devices capable of detecting the low amounts of emitted light. Another type of Ca2+ sensor, referred to as GFP-aequorin (G5A, has been engineered as a chimeric protein, which combines the two photoactive proteins from the jellyfish Aequorea victoria, the green fluorescent protein (GFP and the bioluminescent protein aequorin. The Ca2+-dependent light-emitting property of G5A is based on a bioluminescence resonance energy transfer (BRET between aequorin and GFP. G5A has been used for over 10 years for enhanced in vivo detection of Ca2+ signals in animal tissues.Here, we apply G5A in Arabidopsis and show that G5A greatly improves the imaging of Ca2+ dynamics in intact plants. We describe a simple method to image Ca2+ signals in autofluorescent leaves of plants with a cooled charge-coupled device (cooled CCD camera. We present data demonstrating how plants expressing the G5A probe can be powerful tools for imaging of Ca2+ signals. It is shown that Ca2+ signals propagating over long distances can be visualized in intact plant leaves and are visible mainly in the veins.

  3. Localization of the contacts between Kenyon cells and aminergic neurons in the Drosophila melanogaster brain using SplitGFP reconstitution.

    Science.gov (United States)

    Pech, Ulrike; Pooryasin, Atefeh; Birman, Serge; Fiala, André

    2013-12-01

    The mushroom body of the insect brain represents a neuronal circuit involved in the control of adaptive behavior, e.g., associative learning. Its function relies on the modulation of Kenyon cell activity or synaptic transmitter release by biogenic amines, e.g., octopamine, dopamine, or serotonin. Therefore, for a comprehensive understanding of the mushroom body, it is of interest not only to determine which modulatory neurons interact with Kenyon cells but also to pinpoint where exactly in the mushroom body they do so. To accomplish the latter, we made use of the GRASP technique and created transgenic Drosophila melanogaster that carry one part of a membrane-bound splitGFP in Kenyon cells, along with a cytosolic red fluorescent marker. The second part of the splitGFP is expressed in distinct neuronal populations using cell-specific Gal4 drivers. GFP is reconstituted only if these neurons interact with Kenyon cells in close proximity, which, in combination with two-photon microscopy, provides a very high spatial resolution. We characterize spatially and microstructurally distinct contact regions between Kenyon cells and dopaminergic, serotonergic, and octopaminergic/tyraminergic neurons in all subdivisions of the mushroom body. Subpopulations of dopaminergic neurons contact complementary lobe regions densely. Octopaminergic/tyraminergic neurons contact Kenyon cells sparsely and are restricted mainly to the calyx, the α'-lobes, and the γ-lobes. Contacts of Kenyon cells with serotonergic neurons are heterogeneously distributed over the entire mushroom body. In summary, the technique enables us to localize precisely a segmentation of the mushroom body by differential contacts with aminergic neurons.

  4. Validation of eGFP fluorescence intensity for testing in vitro cytotoxicity according to ISO 10993-5.

    Science.gov (United States)

    Miller, Felicitas; Hinze, Ulf; Chichkov, Boris; Leibold, Wolfgang; Lenarz, Thomas; Paasche, Gerrit

    2017-05-01

    ISO 10993-5 provides one of the accepted standards for testing the biotoxicity of new materials. All of the recommended test procedures rely upon the uptake or metabolism of dye by living cells. Results of direct contact tests can be potentially compromised by interaction or adsorption of the dye or its metabolic products. Therefore, the aim of the current study was to validate the use of the eGFP signal of transfected NIH-3T3 fibroblasts with the results of the MTT test in order to provide a test procedure that is very close to the ISO 10993-5 but has the advantage of not relying on the addition of dye. Our tests show that the MTT assay detects cytotoxicity in the eGFP NIH-3T3 cells at least as well as in the L929 cells. To facilitate the validation, we chose to integrate the fluorescence measurements into the MTT test procedure. To that end, an additional washing step was introduced. Additionally, medium without phenol red was used, resulting in a very high correlation of both measurements. Without these modifications, the fluorescence test was comparable to the MTT test in its ability to detect the cytotoxic potential of substances; however, it did result in slightly elevated IC50 concentrations. As the results of both tests correlated highly, measurement of the eGFP signal appears to present a reliable tool for detecting cytotoxicity of materials in line with the ISO 10993-5 norm with the advantage of avoiding the addition of dyes and the subsequent potential interaction with test materials. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 715-722, 2017. © 2015 Wiley Periodicals, Inc.

  5. Assessment of GFP fluorescence in cells of Streptococcus gordonii under conditions of low pH and low oxygen concentration

    DEFF Research Database (Denmark)

    Hansen, M.C.; Palmer, R.J.; Udsen, C.

    2001-01-01

    Use of green fluorescent protein (GFP) as a molecular reporter is restricted by several environmental factors, such as its requirement for oxygen in the development of the fluorophore, and its poor fluorescence at low pH. There are conflicting data on these limitations, however, and systematic...... biofilm of this organism. Production of lactic acid and the subsequent acidification in batch cultures of S. gordonii DL1 led to a decrease in fluorescence intensity. However, severe pH reduction was prevented when the bacterium was grown as a biofilm in a flowcell, and a homogeneous distribution...

  6. A vector carrying the GFP gene (Green fluorescent protein as a yeast marker for fermentation processes Um vetor com o gene da GFP (Green fluorescent protein para a marcação de leveduras em processos fermentativos

    Directory of Open Access Journals (Sweden)

    Luiz Humberto Gomes

    2000-12-01

    Full Text Available Contaminant yeasts spoil pure culture fermentations and cause great losses in quality and product yields. They can be detected by a variety of methods although none being so efficient for early detection of contaminant yeast cells that appear at low frequency. Pure cultures bearing genetic markers can ease the direct identification of cells and colonies among contaminants. Fast and easy detection are desired and morphological markers would even help the direct visualization of marked pure cultures among contaminants. The GFP gene for green fluorescent protein of Aquorea victoria, proved to be a very efficient marker to visualize transformed cells in mixed populations and tissues. To test this marker in the study of contaminated yeast fermentations, the GFP gene was used to construct a vector under the control of the ADH2 promoter (pYGFP3. Since ADH2 is repressed by glucose the expression of the protein would not interfere in the course of fermentation. The transformed yeasts with the vector pYGFP3 showed high stability and high bioluminescence to permit identification of marked cells among a mixed population of cells. The vector opens the possibility to conduct further studies aiming to develop an efficient method for early detection of spoilage yeasts in industrial fermentative processes.Leveduras contaminantes podem causar grandes perdas em processos fermentativos quando infectam culturas puras e degradam a qualidade do produto final. Estas leveduras podem ser detectadas por diversos métodos mas nenhum deles oferece resultados com a exatidão e precisão necessárias, quando os contaminantes estão em baixa freqüência. Culturas puras contendo um gene marcador podem ser utilizadas para a direta identificação de células e colônias contaminantes. Detecção rápida e fácil é desejada e marcadores morfológicos podem auxiliar na visualização da cultura marcada. O gene da GFP (green fluorescent protein extraído da Aequorea victoria

  7. Uncovering the role of the flexible C-terminal tail: A model study with Strep-tagged GFP

    Directory of Open Access Journals (Sweden)

    Michael W. Lassalle

    2016-06-01

    Full Text Available Recently, it has been recognized that, much like an electric current in an electric circuit, dynamic disruptions from flexible, unstructured regions distal to the active region are transferred through the contact network to the active site and influence protein stability and/or function. As transmembrane proteins frequently possess the β-barrel structure, studies of proteins with this topology are required. The unstructured lid segments of the β-barrel GFP protein are conserved and could play a role in the backbone stabilization required for chromophore function. A study of the disordered C-terminus and the function within the lid is necessary. In this study, we entirely truncated the flexible C-terminal tail and investigated the N-terminal Strep-tagged GFP by fluorescence spectroscopy, and the temperature- and GdnHCl-induced unfolding by circular dichroism. The introduction of the unstructured Strep-tag itself changed the unfolding pathway. Truncating the entire flexible tail did not decrease the fluorescence intensity to a large extent; however, the protein stability changed dramatically. The temperature for half-denaturation T1/2 changed significantly from 79 °C for the wild-type to 72.8 °C for the mutant. Unfolding kinetics at different temperatures have been induced by 4 M GdnHCl, and the apparent Arrhenius activation energy decreased by 40% as compared to the wild-type.

  8. Use of self-assembling GFP to determine protein topology and compartmentalisation in the Plasmodium falciparum-infected erythrocyte.

    Science.gov (United States)

    Külzer, Simone; Petersen, Wiebke; Baser, Avni; Mandel, Katharina; Przyborski, Jude M

    2013-02-01

    In recent years, and largely supported by the increasing use of transfection technology, much research attention has been given to protein trafficking in the Plasmodium falciparum infected red blood cell. By expression of fluorescent reporter proteins, much information has been gained on both the signals and mechanisms directing proteins to their correct sub-cellular localisation within the parasite and infected host cell. Generally however, verification of the observed fluorescent phenotype is carried out using more traditional techniques such as co-immunofluorescence, protease protection, and cell fractionation followed by Western blot. Here we apply a self-assembling split GFP (saGFP) system and show that this can be used to determine both membrane topology and compartmentalisation using transfection technology alone. As an example, we verify the topology of an ER membrane protein, hDer1-1, and of an exported parasite Hsp40 co-chaperone, PFE55. Additionally, we can demonstrate that this system has the potential to be applied to analysis of organellar proteins.

  9. The membrane skeleton in Paramecium: Molecular characterization of a novel epiplasmin family and preliminary GFP expression results.

    Science.gov (United States)

    Pomel, Sébastien; Diogon, Marie; Bouchard, Philippe; Pradel, Lydie; Ravet, Viviane; Coffe, Gérard; Viguès, Bernard

    2006-02-01

    Previous attempts to identify the membrane skeleton of Paramecium cells have revealed a protein pattern that is both complex and specific. The most prominent structural elements, epiplasmic scales, are centered around ciliary units and are closely apposed to the cytoplasmic side of the inner alveolar membrane. We sought to characterize epiplasmic scale proteins (epiplasmins) at the molecular level. PCR approaches enabled the cloning and sequencing of two closely related genes by amplifications of sequences from a macronuclear genomic library. Using these two genes (EPI-1 and EPI-2), we have contributed to the annotation of the Paramecium tetraurelia macronuclear genome and identified 39 additional (paralogous) sequences. Two orthologous sequences were found in the Tetrahymena thermophila genome. Structural analysis of the 43 sequences indicates that the hallmark of this new multigenic family is a 79 aa domain flanked by two Q-, P- and V-rich stretches of sequence that are much more variable in amino-acid composition. Such features clearly distinguish members of the multigenic family from epiplasmic proteins previously sequenced in other ciliates. The expression of Green Fluorescent Protein (GFP)-tagged epiplasmin showed significant labeling of epiplasmic scales as well as oral structures. We expect that the GFP construct described herein will prove to be a useful tool for comparative subcellular localization of different putative epiplasmins in Paramecium.

  10. PiggyBac Transposon Mediated Efficient eGFP Expression in Porcine Somatic Cells and Cloned Embryos

    Institute of Scientific and Technical Information of China (English)

    Luo Yi-bo; Zhang Li; Zhu Jiang; Wu Mei-ling; Huan Yan-jun; Yin Zhi; Mu Yan-shuang; Xia Ping; LiuZhong-hua

    2012-01-01

    PiggyBac transposon has demonstrated its long-term and stable transposition on genomes of various species but lacking of the evidence on farm animal genomes. In this study, we constructed a piggyBac transposon marked with enhanced green fluorescent protein (eGFP) and showed efficient transposition in porcine somatic cells and cloned embryos. Our results demonstrated that piggyBac transposase could efficiently catalyze transposition in porcine fetal fibroblast cells, as well as in embryos. PiggyBac transposition generated 18-fold more eGFP-positive cell colonies compared to pEGFP-C1 random insertion mutagenesis, but excessive transposase might affect the transfection rate. Also piggyBac mediated 4-fold more eGFP expression than random insertion in cells and 17-fold in cloned embryos at mRNA level. When the mutagenized cells were used for somatic cell nuclear transfer (SCNT), the cleavage rate and blastocyst rate of constructed embryos harboring piggyBac transposition had no difference with random insertion group. This study provides key information on the piggyBac transposon system as a tool for creating transgenic pigs.

  11. Quantifying phenotypic variation in isogenic Caenorhabditis elegans expressing Phsp-16.2::gfp by clustering 2D expression patterns.

    Directory of Open Access Journals (Sweden)

    Alexander K Seewald

    Full Text Available Isogenic populations of animals still show a surprisingly large amount of phenotypic variation between individuals. Using a GFP reporter that has been shown to predict longevity and resistance to stress in isogenic populations of the nematode Caenorhabditis elegans, we examined residual variation in expression of this GFP reporter. We found that when we separated the populations into brightest 3% and dimmest 3% we also saw variation in relative expression patterns that distinguished the bright and dim worms. Using a novel image processing method which is capable of directly analyzing worm images, we found that bright worms (after normalization to remove variation between bright and dim worms had expression patterns that correlated with other bright worms but that dim worms fell into two distinct expression patterns. We have analysed a small set of worms with confocal microscopy to validate these findings, and found that the activity loci in these clusters are caused by extremely bright intestine cells. We also found that the vast majority of the fluorescent signal for all worms came from intestinal cells as well, which may indicate that the activity of intestinal cells is responsible for the observed patterns. Phenotypic variation in C. elegans is still not well understood but our proposed novel method to analyze complex expression patterns offers a way to enable a better understanding.

  12. Reporter system for the detection of in vivo gene conversion: changing colors from blue to green using GFP variants.

    Science.gov (United States)

    Sommer, Jeffrey R; Alderson, Jon; Laible, Goetz; Petters, Robert M

    2006-06-01

    We have devised a system for the study of in vivo gene correction based on the detection of color variants of the green fluorescent protein (GFP) from the jellyfish Aequorea victoria. The intensity and spectra of the fluorescence emitted by the blue (BFP) and red-shifted (EGFP) variants of GFP differ from each other. We modified one nucleotide from an EGFP expression vector that we predicted would yield a blue variant (TAC-CAC, Tyr(66)-His(66)). Cells that were either transiently or stably transfected with the reporter system were used to test the functionality and feasibility of the detection of in vivo gene correction. A thio-protected single-stranded oligonucleotide designed to convert the genotype of the blue variant to that of the EGFP variant by the correction of a single base pair was delivered to the reporter cells using a variety of methodologies and strategies.Conversion events were easily observed using fluorescent microscopy because of the enhanced emission intensity and different spectra of the EGFP variant.

  13. [The effects of SV40 PolyA sequence and its AATAAA signal on upstream GFP gene expression and transcription termination].

    Science.gov (United States)

    Li, Shu-Ping; Feng, Jing-Jing; Wang, Hong-Gang; Wang, Xiu-Fang; Lv, Zhan-Jun

    2012-01-01

    SV40 PolyA (Simian virus 40 PolyA, also called PolyA) sequence is DNA sequence (240 bp) that possesses the activity of transcription termination and can add PolyA tail to mRNA. PolyA contains AATAAA hexanucleotide polyadenylation signal. Fourteen copies of Alu in sense orientation (Alu14) were inserted downstream of GFP in pEGFP-C1 to construct pAlu14 plasmid, and then HeLa cells were transiently transfected with pAlu14. Northern blot and fluorescence microscope were used to observe GFP RNA and protein expressions. Our results found that Alu tandem sequence inhibited remarkably GFP gene expression, but produced higher-molecular-mass GFP fusion RNA. PolyA and its sequence that was deleted AATAAA signal in sense or antisense orientation were inserted between GFP and Alu tandem sequence in pAlu14. The results showed that all the inserted PolyA sequences partly eliminated the inhibition induced by Alu14. PolyA sequences without AATAAA signal in sense or antisense orientation still induced transcription termination. Antisense PolyA (PolyAas) was divided into four fragments that all are 60 bp long and the middle two fragments were named 2F2R and 3F3R. 2F2R or 3F3R was inserted upstream of Alu tandem sequence in pAlu14. The molecular mass of GFP fusion RNA increased when the copy number of 2F2R increased. 2F2R can support transcription elongation when 2F2R is located upstream of other 2F2R. Nevertheless, 2F2R located upstream of Alu tandem sequence can induce transcription termination. Inserting one copy or 64 copies of 3F3R in upstream of Alu tandem sequence caused the production of lower-molecular-mass GFP RNA.

  14. Lack of organ specific commitment of vagal neural crest cell derivatives as shown by back-transplantation of GFP chicken tissues.

    Science.gov (United States)

    Freem, Lucy J; Delalande, Jean Marie; Campbell, Alison M; Thapar, Nikhil; Burns, Alan J

    2012-01-01

    Neural crest cells (NCC) are multipotent progenitors that migrate extensively throughout the developing embryo and generate a diverse range of cell types. Vagal NCC migrate from the hindbrain into the foregut and from there along the gastrointestinal tract to form the enteric nervous system (ENS), the intrinsic innervation of the gut, and into the developing lung buds to form the intrinsic innervation of the lungs. The aim of this study was to determine the developmental potential of vagal NCC that had already colonised the gut or the lungs. We used transgenic chicken embryos that ubiquitously express green fluorescent protein (GFP) to permanently mark and fate-map vagal NCC using intraspecies grafting. This was combined with back-transplantation of gut and lung segments, containing GFP-positive NCC, into the vagal region of a second recipient embryo to determine, using immunohistochemical staining, whether gut or lung NCC are competent of re-colonising both these organs, or whether their fate is restricted. Chick(GFP)-chick intraspecies grafting efficiently labelled NCC within the gut and lung of chick embryos. When segments of embryonic day (E)5.5 pre-umbilical midgut containing GFP-positive NCC were back-transplanted into the vagal region of E1.5 host embryos, the GFP-positive NCC remigrated to colonise both the gut and lungs and differentiated into neurons in stereotypical locations. However, GFP-positive lung NCC did not remigrate when back-transplanted. Our studies suggest that gut NCC are not restricted to colonising only this organ, since upon back-transplantation GFP-positive gut NCC colonised both the gut and the lung.

  15. Asparaginase II-GFP fusion as a tool for studying the secretion of the enzyme under nitrogen starvation Fusão asparaginase II-GFP como ferramenta para estudo da via secretora de enzima sobre depleção por nitrogênio

    Directory of Open Access Journals (Sweden)

    Adriana Sotero-Martins

    2003-12-01

    Full Text Available Production of asparaginase II of Saccharomyces cerevisiae is regulated by nitrogen and can be used as a model system for studying other secreted proteins in yeast. Green fluorescent protein (GFP from Aequorea victoria was fused to the carboxy-terminus of the enzyme by genomic integration to the locus ASP3 of S. cerevisiae. We determined asparaginase II activity, mRNA ASP3, mRNA ASP3-GFP and GFP fluorescence. Nitrogen starvation in cells carrying the chimera ASP3-GFP caused an increase in fluorescence and in the expression of ASP3. We have shown that cells producing the chimera Asp3-GFPp displayed the same response to nitrogen starvation as control cells. We demonstrated that Asp3-GFPp can be used for studying asparaginase II secretion under nitrogen starvation in vivo.A produção de asparaginase II de Saccharomyces cerevisiae é regulada por nitrogênio e pode ser utilizada como um sistema modelo para estudar outras proteínas secretadas, em leveduras. A proteína "green fluorescent protein" (GFP de Aequorea victoria foi fusionada à porção carboxi-terminal de Asp3p por integração genômica da sequência de GFP ao locus ASP3. Determinaram-se os níveis de atividade de asparaginase II, mRNA ASP3, mRNA ASP3-GFP e de fluorescência para GFP. A depleção para nitrogênio, em células portadoras do gene quimérico ASP3-GFP, fez aumentar a fluorescência, assim como a expressão de ASP3. Demonstramos que Asp3-GFPp pode ser utilizada para estudar a secreção de asparaginase II em células submetidas à privação de nitrogênio in vivo.

  16. AUTOCOUNTER, an ImageJ JavaScript to analyze LC3B-GFP expression dynamics in autophagy-induced astrocytoma cells.

    Science.gov (United States)

    Fassina, L; Magenes, G; Inzaghi, A; Palumbo, S; Allavena, G; Miracco, C; Pirtoli, L; Biggiogera, M; Comincini, S

    2012-10-11

    An ImageJ JavaScript, AUTOCOUNTER, was specifically developed to monitor and measure LC3B-GFP expression in living human astrocytoma cells, namely T98G and U373-MG. Discrete intracellular GFP fluorescent spots derived from transduction of a Baculovirus replication-defective vector (BacMam LC3B-GFP), followed by microscope examinations at different times. After viral transgene expression, autophagy was induced by Rapamycin administration and assayed in ph-p70S6K/p70S6K and LC3B immunoblotting expression as well as by electron microscopy examinations. A mutated transgene, defective in LC3B lipidation, was employed as a negative control to further exclude fluorescent dots derived from protein intracellular aggregation. The ImageJ JavaScript was then employed to evaluate and score the dynamics changes of the number and area of LC3B-GFP puncta per cell in time course assays and in complex microscope examinations. In conclusion, AUTOCOUNTER enabled to quantify LC3B-GFP expression and to monitor dynamics changes in number and shapes of autophagosomal-like vesicles: it might therefore represent a suitable algorithmic tool for in vitro autophagy modulation studies.

  17. Arabidopsis Gene Family Profiler (aGFP – user-oriented transcriptomic database with easy-to-use graphic interface

    Directory of Open Access Journals (Sweden)

    Reňák David

    2007-07-01

    Full Text Available Abstract Background Microarray technologies now belong to the standard functional genomics toolbox and have undergone massive development leading to increased genome coverage, accuracy and reliability. The number of experiments exploiting microarray technology has markedly increased in recent years. In parallel with the rapid accumulation of transcriptomic data, on-line analysis tools are being introduced to simplify their use. Global statistical data analysis methods contribute to the development of overall concepts about gene expression patterns and to query and compose working hypotheses. More recently, these applications are being supplemented with more specialized products offering visualization and specific data mining tools. We present a curated gene family-oriented gene expression database, Arabidopsis Gene Family Profiler (aGFP; http://agfp.ueb.cas.cz, which gives the user access to a large collection of normalised Affymetrix ATH1 microarray datasets. The database currently contains NASC Array and AtGenExpress transcriptomic datasets for various tissues at different developmental stages of wild type plants gathered from nearly 350 gene chips. Results The Arabidopsis GFP database has been designed as an easy-to-use tool for users needing an easily accessible resource for expression data of single genes, pre-defined gene families or custom gene sets, with the further possibility of keyword search. Arabidopsis Gene Family Profiler presents a user-friendly web interface using both graphic and text output. Data are stored at the MySQL server and individual queries are created in PHP script. The most distinguishable features of Arabidopsis Gene Family Profiler database are: 1 the presentation of normalized datasets (Affymetrix MAS algorithm and calculation of model-based gene-expression values based on the Perfect Match-only model; 2 the choice between two different normalization algorithms (Affymetrix MAS4 or MAS5 algorithms; 3 an intuitive

  18. Combined use of different Gfp reporters for monitoring single-cell activities of a genetically modified PCB degrader in the rhizosphere of alfalfa

    DEFF Research Database (Denmark)

    Boldt, T.S.; Sørensen, J.; Karlsson, U.

    2004-01-01

    of chlorinated biphenyl was constructed, using another gfp fusion with the meta-pathway Pin promoter from Pseudomonas putida (TOL plasmid). Expression of this promoter, which is strongly induced by the PCB-2 degradation product, 3-chlorobenzoate, was tested in vitro and subsequently monitored in vivo on alfalfa...... roots using the P. fluorescens F113rifpcb reporter. A small but distinct fraction of the introduced bacteria activated the Pm promoter and thus appeared to sense a PCB-2 degradation product in the alfalfa rhizosphere. The degrading cells, which by design were identical to the sensing cells, were located......Single-cell localization and activity of Pseudomonas,fluorescens F113, colonizing alfalfa roots, were monitored using fusions of the Escherichia coli rrnBP1 ribosomal promoter and gfp genes encoding green fluorescent protein (Gfp) of different stability. The monitoring systems permitted non...

  19. Combined use of different Gfp reporters for monitoring single-cell activities of a genetically modified PCB degrader in the rhizosphere of alfalfa

    DEFF Research Database (Denmark)

    Boldt, T.S.; Sørensen, J.; Karlsson, U.

    2004-01-01

    Single-cell localization and activity of Pseudomonas,fluorescens F113, colonizing alfalfa roots, were monitored using fusions of the Escherichia coli rrnBP1 ribosomal promoter and gfp genes encoding green fluorescent protein (Gfp) of different stability. The monitoring systems permitted non...... of chlorinated biphenyl was constructed, using another gfp fusion with the meta-pathway Pin promoter from Pseudomonas putida (TOL plasmid). Expression of this promoter, which is strongly induced by the PCB-2 degradation product, 3-chlorobenzoate, was tested in vitro and subsequently monitored in vivo on alfalfa...... roots using the P. fluorescens F113rifpcb reporter. A small but distinct fraction of the introduced bacteria activated the Pm promoter and thus appeared to sense a PCB-2 degradation product in the alfalfa rhizosphere. The degrading cells, which by design were identical to the sensing cells, were located...

  20. Antigen Uptake during Different Life Stages of Zebrafish (Danio rerio) Using a GFP-Tagged Yersinia ruckeri

    DEFF Research Database (Denmark)

    Korbut, Rozalia; Mehrdana, Foojan; Kania, Per Walter;

    2016-01-01

    Immersion-vaccines (bacterins) are routinely used for aquacultured rainbow trout to protect against Yersinia ruckeri (Yr). During immersion vaccination, rainbow trout take up and process the antigens, which induce protection. The zebrafish was used as a model organism to study uptake mechanisms...... the gut was consistently a major uptake site. Zebrafish and rainbow trout tend to have similar uptake mechanisms following immersion or bath vaccination, which points towards zebrafish as a suitable model organism for this aquacultured species....... and subsequent antigen transport in fish. A genetically modified Yr was developed to constitutively express green fluorescent protein (GFP) and was used for bacterin production. Larval, juvenile and adult transparent zebrafish (tra:nac mutant) received a bath in the bacterin for up to 30 minutes. Samples were...

  1. A nanobody:GFP bacterial platform that enables functional enzyme display and easy quantification of display capacity

    DEFF Research Database (Denmark)

    Wendel, Sofie; Christian Fischer, Emil; Martinez, Virginia;

    2016-01-01

    Background: Bacterial surface display is an attractive technique for the production of cell-anchored, functional proteins and engineering of whole-cell catalysts. Although various outer membrane proteins have been used for surface display, an easy and versatile high-throughput-compatible assay...... for evaluating and developing surface display systems is missing.Results: Using a single domain antibody (also called nanobody) with high affinity for green fluorescent protein (GFP), we constructed a system that allows for fast, fluorescence-based detection of displayed proteins. The outer membrane hybrid...... protein LppOmpA and the autotransporter C-IgAP exposed the nanobody on the surface of Escherichia coli with very different efficiency. Both anchors were capable of functionally displaying the enzyme Chitinase A as a fusion with the nanobody, and this considerably increased expression levels compared...

  2. Generation of GFP Reporter Human Induced Pluripotent Stem Cells Using AAVS1 Safe Harbor Transcription Activator-Like Effector Nuclease.

    Science.gov (United States)

    Luo, Yongquan; Rao, Mahendra; Zou, Jizhong

    2014-05-16

    Generation of a fluorescent GFP reporter line in human induced pluripotent stem cells (hiPSCs) provides enormous potentials in both basic stem cell research and regenerative medicine. A protocol for efficiently generating such an engineered reporter line by gene targeting is highly desired. Transcription activator-like effector nucleases (TALENs) are a new class of artificial restriction enzymes that have been shown to significantly promote homologous recombination by >1000-fold. The AAVS1 (adeno-associated virus integration site 1) locus is a "safe harbor" and has an open chromatin structure that allows insertion and stable expression of transgene. Here, we describe a step-by-step protocol from determination of TALENs activity, hiPSC culture, and delivery of a donor into AAVS1 targeting site, to validation of targeted integration by PCR and Southern blot analysis using hiPSC line, and a pair of open-source AAVS1 TALENs.

  3. A transgenic Plasmodium falciparum NF54 strain that expresses GFP-luciferase throughout the parasite life cycle.

    Science.gov (United States)

    Vaughan, Ashley M; Mikolajczak, Sebastian A; Camargo, Nelly; Lakshmanan, Viswanathan; Kennedy, Mark; Lindner, Scott E; Miller, Jessica L; Hume, Jen C C; Kappe, Stefan H I

    2012-12-01

    Plasmodium falciparum is the pathogenic agent of the most lethal of human malarias. Transgenic P. falciparum parasites expressing luciferase have been created to study drug interventions of both asexual and sexual blood stages but luciferase-expressing mosquito stage and liver stage parasites have not been created which has prevented the easy quantification of mosquito stage development (e.g. for transmission blocking interventions) and liver stage development (for interventions that prevent infection). To overcome this obstacle, we have created a transgenic P. falciparum NF54 parasite that expresses a GFP-luciferase transgene throughout the life cycle. Luciferase expression is robust and measurable at all life cycle stages, including midgut oocyst, salivary gland sporozoites and liver stages, where in vivo development is easily measurable using humanized mouse infections in conjunction with an in vivo imaging system. This parasite reporter strain will accelerate testing of interventions against pre-erythrocytic life cycle stages.

  4. Hippocampal neurogenesis in the APP/PS1/nestin-GFP triple transgenic mouse model of Alzheimer's disease.

    Science.gov (United States)

    Zeng, Q; Zheng, M; Zhang, T; He, G

    2016-02-09

    Alzheimer's disease (AD) is one of the most common causes of dementia. Although the exact mechanisms of AD are not entirely clear, the impairment in adult hippocampal neurogenesis has been reported to play a role in AD. To assess the relationship between AD and neurogenesis, we studied APP/PS1/nestin-green fluorescent protein (GFP) triple transgenic mice, a well-characterized mouse model of AD, which express GFP under the control of the nestin promoter. Different ages of AD mice and their wild-type littermates (WT) were used in our study. Immunofluorescent staining showed that neurogenesis occurred mainly in the subgranular zone (SGZ) of the dentate gyrus (DG) and subventricular zone (SVZ) of the lateral ventricles (LVs). The expression of neural stem cells (NSCs) (nestin) and neural precursors such as doublecortin (DCX) and GFAP in AD mice were decreased with age, as well as there being a reduction in 5-bromo-2-deoxyuridine (BrdU)-positive cells, when compared to WT. However, the number of maturate neurons (NeuN) was not significantly different between AD mice and wild-type controls, and NeuN changed only slightly with age. By Golgi-Cox staining, the morphologies of dendrites were observed, and significant differences existed between AD mice and wild-type controls. These results suggest that AD has a far-reaching influence on the regulation of adult hippocampal neurogenesis, leading to a gradual decrease in the generation of neural progenitors (NPCs), and inhibition of the differentiation and maturation of neurons.

  5. Use of the GFP reporter as a vital marker for Agrobacterium-mediated transformation of sugar beet (Beta vulgaris L.).

    Science.gov (United States)

    Zhang, C L; Chen, D F; McCormac, A C; Scott, N W; Elliott, M C; Slater, A

    2001-02-01

    Molecular approaches to sugar beet improvement will benefit from an efficient transformation procedure that does not rely upon exploitation of selectable marker genes such as those which confer antibiotic or herbicide resistance upon the transgenic plants. The expression of the green fluorescent protein (GFP) signal has been investigated during a program of research that was designed to address the need to increase the speed and efficiency of selection of sugar beet transformants. It was envisaged that the GFP reporter could be used initially as a supplement to current selection regimes in order to help eliminate "escapes" and perhaps eventually as a replacement marker in order to avoid the public disquiet associated with antibiotic/herbicide-resistance genes in field-released crops. The sgfp-S65T gene has been modified to have a plant-compatible codon usage, and a serine to threonine mutation at position 65 for enhanced fluorescence under blue light. This gene, under the control of the CaMV 35S promoter, was introduced into sugar beet via Agrobacterium-mediated transformation. Early gene expression in cocultivated sugar beet cultures was signified by green fluorescence several days after cocultivation. Stably transformed calli, which showed green fluorescence at a range of densities, were obtained at frequencies of 3-11% after transferring the inoculated cultures to selection media. Cocultivated shoot explants or embryogenic calli were regularly monitored under the microscope with blue light when they were transferred to media without selective agents. Green fluorescent shoots were obtained at frequencies of 2-5%. It was concluded that the sgfp-S65T gene can be used as a vital marker for noninvasive screening of cells and shoots for transformation, and that it has potential for the development of selectable marker-free transgenic sugar beet.

  6. Expression patterns of the native Shrunken-2 promoter in Sorghum bicolor visualised through use of the GFP reporter gene.

    Science.gov (United States)

    Lamont, Kyle C; Mudge, Stephen R; Liu, Guoquan; Godwin, Ian D

    2017-07-18

    The AGPase large subunit (shrunken-2) promoter was demonstrated to be active in the placentochalaza and endosperm of developing grain as well as the root tips in transgenic sorghum. The temporal and spatial expression patterns of the Sorghum bicolor Shrunken-2 (Sh2) promoter were evaluated using the green fluorescence protein reporter gene (gfp) in transgenic sorghum, within the context of upregulating starch biosynthesis in the developing grain. GFP fluorescence was analysed throughout development in various tissue types using confocal laser scanning microscopy techniques. Sh2 promoter activity was first detected in the placentochalaza region of the developing caryopsis and apoplasm adjacent to the nucellar epidermis at 7 days post anthesis (dpa) where fluorescence remained relatively constant until 17 dpa. Fluorescence in this region weakened by 20 dpa and disappeared by 25 dpa. Expression was also detected in the developing endosperm, but not until 12 dpa, continuing until 25 dpa. Whilst the endosperm expression was expected, the fluorescence detected in the placentochalaza was completely unexpected. Although transcript presence does not mean the resulting biochemistry is also present, these preliminary findings may suggest alternate spatial activity of ADP-glucose pyrophosphorylase prior to uptake by the developing grain. Sh2 promoter activity was also unexpectedly detected in the root tips at all developmental time points. Sh2 promoter activity was not detected in any reproductive floral tissue (both pre and post anthesis) or in pollen. Similarly, no expression was detected in leaf tissue at any stage.

  7. A Mason-Pfizer Monkey virus Gag-GFP fusion vector allows visualization of capsid transport in live cells and demonstrates a role for microtubules.

    Directory of Open Access Journals (Sweden)

    Jasmine Clark

    Full Text Available Immature capsids of the Betaretrovirus, Mason-Pfizer Monkey virus (M-PMV, are assembled in the pericentriolar region of the cell, and are then transported to the plasma membrane for budding. Although several studies, utilizing mutagenesis, biochemistry, and immunofluorescence, have defined the role of some viral and host cells factors involved in these processes, they have the disadvantage of population analysis, rather than analyzing individual capsid movement in real time. In this study, we created an M-PMV vector in which the enhanced green fluorescent protein, eGFP, was fused to the carboxyl-terminus of the M-PMV Gag polyprotein, to create a Gag-GFP fusion that could be visualized in live cells. In order to express this fusion protein in the context of an M-PMV proviral backbone, it was necessary to codon-optimize gag, optimize the Kozak sequence preceding the initiating methionine, and mutate an internal methionine codon to one for alanine (M100A to prevent internal initiation of translation. Co-expression of this pSARM-Gag-GFP-M100A vector with a WT M-PMV provirus resulted in efficient assembly and release of capsids. Results from fixed-cell immunofluorescence and pulse-chase analyses of wild type and mutant Gag-GFP constructs demonstrated comparable intracellular localization and release of capsids to untagged counterparts. Real-time, live-cell visualization and analysis of the GFP-tagged capsids provided strong evidence for a role for microtubules in the intracellular transport of M-PMV capsids. Thus, this M-PMV Gag-GFP vector is a useful tool for identifying novel virus-cell interactions involved in intracellular M-PMV capsid transport in a dynamic, real-time system.

  8. Immunogenicity and Efficacy of Live L. tarentolae Expressing KMP11-NTGP96-GFP Fusion as a Vaccine Candidate against Experimental Visceral Leishmaniasis Caused by L. infantum

    Directory of Open Access Journals (Sweden)

    Vahid NASIRI

    2016-10-01

    Full Text Available Background: The aim of present study was to evaluate the protective efficacy of live recombinant L. tarentolae expressing KMP11-NTGP96-GFP fusion as candidates for live engineered recombinant vaccine against visceral leishmaniasis in BALB/c mice.Methods: KMP-11 and NT-GP96 genes cloned into the pJET1.2/blunt cloning vector and then into pEGFP-N1 expression vector. The KMP-11, NT-GP96 and GFP fused in pEGFP-N1 and subcloned into Leishmanian pLEXSY-neo vector. Finally this construct was transferred to L. tarentolae by electroporation. Tranfection was confirmed by SDS-PAGE, WESTERN blot, flowcytometry and RT-PCR. Protective efficacy of this construct was evaluated as a vaccine candidate against visceral leishmaniasis. Parasite burden, humoral and cellular immune responses were assessed before and at 4 weeks after challenge.Results: KMP- NT-Gp96-GFP Fusion was cloned successfully into pLEXSY -neo vector and this construct successfully transferred to L. tarentolae. Finding indicated that immunization with L. tarentolae tarentolae-KMP11-NTGP96-GFP provides significant protection against visceral leishmaniasis and was able to induce an increased expression of IFN-γ and IgG2a. Following challenge, a reduced parasite load in the spleen of the KMP11-NTGP96-GFP immunized group was detected.Conclusion: The present study is the first to use a combination of a Leishmania antigen with an immunologic antigen in live recombinant L. tarentolae and results suggest that L. tarentolae-KMP11-NTGP96-GFP could be considered as a potential tool in vaccination against visceral leishmaniasis and this vaccination strategy could provide a potent rout for future vaccine development. 

  9. Transduction and oncolytic profile of a potent replication-competent adenovirus 11p vector (RCAd11pGFP in colon carcinoma cells.

    Directory of Open Access Journals (Sweden)

    Jim Silver

    Full Text Available Replication-competent adenovirus type 5 (Ad5 vectors promise to be more efficient gene delivery vehicles than their replication-deficient counterparts, and chimeric Ad5 vectors that are capable of targeting CD46 are more effective than Ad5 vectors with native fibers. Although several strategies have been used to improve gene transduction and oncolysis, either by modifying their tropism or enhancing their replication capacity, some tumor cells are still relatively refractory to infection by chimeric Ad5. The oncolytic effects of the vectors are apparent in certain tumors but not in others. Here, we report the biological and oncolytic profiles of a replication-competent adenovirus 11p vector (RCAd11pGFP in colon carcinoma cells. CD46 was abundantly expressed in all cells studied; however, the transduction efficiency of RCAd11pGFP varied. RCAd11pGFP efficiently transduced HT-29, HCT-8, and LS174T cells, but it transduced T84 cells, derived from a colon cancer metastasis in the lung, less efficiently. Interestingly, RCAd11p replicated more rapidly in the T84 cells than in HCT-8 and LS174T cells and as rapidly as in HT-29 cells. Cell toxicity and proliferation assays indicated that RCAd11pGFP had the highest cell-killing activities in HT29 and T84 cells, the latter of which also expressed the highest levels of glycoproteins of the carcinoma embryonic antigen (CEA family. In vivo experiments showed significant growth inhibition of T84 and HT-29 tumors in xenograft mice treated with either RCAd11pGFP or Ad11pwt compared to untreated controls. Thus, RCAd11pGFP has a potent cytotoxic effect on colon carcinoma cells.

  10. LDL receptor-GFP fusion proteins: new tools for the characterization of disease-causing mutations in the LDL receptor gene

    DEFF Research Database (Denmark)

    Holst, Henrik Uffe; Dagnæs-Hansen, Frederik; Corydon, Thomas Juhl;

    2001-01-01

    The function of a series of LDL receptor GFP fusion proteins with different, flexible, unstructured spacer regions was analysed. An optimised version of the fusion protein was used to analyse the effect of a LDL receptor mutation (W556S) found in FH patients and characterized as transport defective....... In cultured liver cells this mutation was found to inhibit the transport of LDL receptor GFP fusion protein to the cell surface, thus leading to impaired internalisation of fluorescent labelled LDL. Co-locallisation studies confirmed the retention of the mutant protein in the endoplasmic reticulum....

  11. Comparison of label-free and GFP multiphoton imaging of hair follicle-associated pluripotent (HAP) stem cells in mouse whiskers.

    Science.gov (United States)

    Uchugonova, Aisada; Cao, Wenluo; Hoffman, Robert M; Koenig, Karsten

    2015-01-01

    Hair-follicle-associated pluripotent (HAP) stem cells can differentiate into many cell types, including neurons and heart muscle cells, and have been shown to repair peripheral nerves and the spinal cord in mice. HAP stem cells can be obtained from each individual patient for regenerative medicine which overcomes problems with immune rejection. Previously, we have demonstrated that genetically-encoded protein markers such as GFP in transgenic mice can be used to visualize HAP stem cells in vivo by multiphoton tomography. Detection and visualization of stem cells in vivo without exogenous labels such as GFP would be important for human application. In the present report, we demonstrate label-free visualization of hair follicle stem cells in mouse whiskers by multiphoton tomography due to the intrinsic fluorophores such as NAD(P)H/flavins. We compared multiphoton tomography of GFP-labeled HAP stem cells and unlabeled stem cells in isolated mouse whiskers. We show that observation of HAP stem cells by label-free multiphoton tomography is comparable to detection using GFP-labeled stem cells. The results described here have important implications for detection and isolation of human HAP stem cells for regenerative medicine.

  12. Confocal/TEM overlay microscopy: a simple method for correlating confocal and electron microscopy of cells expressing GFP/YFP fusion proteins.

    Science.gov (United States)

    Keene, Douglas R; Tufa, Sara F; Lunstrum, Gregory P; Holden, Paul; Horton, William A

    2008-08-01

    Genetic manipulation allows simultaneous expression of green fluorescent protein (GFP) and its derivatives with a wide variety of cellular proteins in a variety of living systems. Epifluorescent and confocal laser scanning microscopy (confocal) localization of GFP constructs within living tissue and cell cultures has become routine, but correlation of light microscopy and high resolution transmission electron microscopy (TEM) on components within identical cells has been problematic. In this study, we describe an approach that specifically localizes the position of GFP/yellow fluorescent protein (YFP) constructs within the same cultured cell imaged in the confocal and transmission electron microscopes. We present a simplified method for delivering cell cultures expressing fluorescent fusion proteins into LR White embedding media, which allows excellent GFP/YFP detection and also high-resolution imaging in the TEM. Confocal images from 0.5-microm-thick sections are overlaid atop TEM images of the same cells collected from the next serial ultrathin section. The overlay is achieved in Adobe Photoshop by making the confocal image somewhat transparent, then carefully aligning features within the confocal image over the same features visible in the TEM image. The method requires no specialized specimen preparation equipment; specimens are taken from live cultures to embedding within 8 h, and confocal transmission overlay microscopy can be completed within a few hours.

  13. Optimizing expression and purification of an ATP-binding gene gsiA from Escherichia coli k-12 by using GFP fusion

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    Zhongshan Wang

    2011-01-01

    Full Text Available The cloning, expression and purification of the glutathione (sulfur import system ATP-binding protein (gsiA was carried out. The coding sequence of Escherichia coli gsiA, which encodes the ATP-binding protein of a glutathione importer, was amplified by PCR, and then inserted into a prokaryotic expression vector pWaldo-GFPe harboring green fluorescent protein (GFP reporter gene. The resulting recombinant plasmid pWaldo-GFP-GsiA was transformed into various E. coli strains, and expression conditions were optimized. The effect of five E. coli expression strains on the production of the recombinant gsiA protein was evaluated. E. coli BL21 (DE3 was found to be the most productive strain for GsiA-GFP fusion-protein expression, most of which was insoluble fraction. However, results from in-gel and Western blot analysis suggested that expression of recombinant GsiA in Rosetta (DE3 provides an efficient source in soluble form. By using GFP as reporter, the most suitable host strain was conveniently obtained, whereby optimizing conditions for overexpression and purification of the proteins for further functional and structural studies, became, not only less laborious, but also time-saving.

  14. Use of GFP-tagged strains of Penicillium digitatum and Penicillium expansum to study host-pathogen interactions in oranges and apples.

    Science.gov (United States)

    Buron-Moles, G; López-Pérez, M; González-Candelas, L; Viñas, I; Teixidó, N; Usall, J; Torres, R

    2012-11-15

    Penicillium digitatum and Penicillium expansum are responsible for green and blue molds in citrus and pome fruits, respectively, which result in major monetary losses worldwide. In order to study their infection process in fruits, we successfully introduced a green fluorescent protein (GFP) encoding gene into wild type P. digitatum and P. expansum isolates, using Agrobacterium tumefaciens-mediated transformation (ATMT), with hygromycin B resistance as the selectable marker. To our knowledge, this is the first report describing the transformation of these two important postharvest pathogens with GFP and the use of transformed strains to study compatible and non-host pathogen interactions. Transformation did not affect the pathogenicity or the ecophysiology of either species compared to their respective wild type strains. The GFP-tagged strains were used for in situ analysis of compatible and non-host pathogen interactions on oranges and apples. Knowledge of the infection process of apples and oranges by these pathogens will facilitate the design of novel strategies to control these postharvest diseases and the use of the GFP-tagged strains will help to determine the response of P. digitatum and P. expansum on/in plant surface and tissues to different postharvest treatments.

  15. Simultaneous tracking of movement and gene expression in multiple Drosophila melanogaster flies using GFP and DsRED fluorescent reporter transgenes

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    Tavaré Simon

    2009-04-01

    Full Text Available Abstract Background Fluorescent proteins such as GFP (Green Fluorescent Protein and DsRED (Discosoma sp.Red Fluorescent Protein are often used as reporter molecules for transgene expression in Drosophila and other species. We have recently reported methods that allow simultaneous tracking of animal movement and GFP expression in real time, however the assay was limited to single animals and a single transgene. Numerous studies would be facilitated by methods that allow for assay of multiple animals and multiple transgenes. Findings Here we report an improved fly video tracking system that allows multiple transgenic flies to be tracked simultaneously using visible light, GFP fluorescence and DsRED fluorescence. The movement of multiple flies could be accurately tracked at real time rates, while simultaneously assaying the expression level of two different transgenes marked with GFP and DsRED. The individual flies could be accurately tracked and distinguished even during periods when transgene fluorescence was undetected. For example, characteristic patterns of hsp70 and hsp22 transgene induction could be simultaneously quantified and correlated with animal movement in aging flies, and as groups of flies died due to dessication/starvation. Conclusion The improved methods allow for more efficient assay of the correlation between gene expression, behavior, aging and mortality: multiple animals can be assayed with simultaneous quantification of multiple transgenes using GFP and DsRED fluorescence. These methods should allow for increased flexibility in experimental designs. For example, in the future it should be possible to use gene expression levels to predict remaining life span more accurately, and to quantify gene expression changes caused by interactions between animals in real time.

  16. BCL10GFP fusion protein as a substrate for analysis of determinants required for Mucosa-Associated Lymphoid Tissue 1 (MALT1-mediated cleavage

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    Jou Shin-Yi

    2012-10-01

    Full Text Available Abstract Background MALT1 belongs to a family of paracaspase and modulates NF-κB signaling pathways through its scaffolding function and proteolytic activity. MALT1 cleaves protein substrates after a positively charged Arginine residue. BCL10, a 233 amino acids polypeptide, is identified as one of the MALT1 proteolytic substrates. MALT1 cleaves BCL10 at the C-terminal end of Arg228. A mere 5 amino acids difference between the substrate and the proteolytic product made it difficult to tell whether the cleavage event took place by using a simple western blot analysis. Here, BCL10GFP was constructed and utilized to examine the specificity and domain determinants for MALT1 cleavage in cells. Methods Various BCL10GFP constructs were transfected into HEK293T cell with MALT1 construct by using calcium phosphate-DNA precipitation method. Lysates of transfectants were resolved by SDS/PAGE and analyzed by western blot analysis. Results BCL10GFP was proteolytically processed by MALT1 as BCL10. The integrity of caspase recruitment domain (CARD and MALT1-interacting domain on BCL10 were required for MALT1 proteolytic activity. Besides the invariant P1 cleavage site Arg228, P4 Leu225 played a role in defining BCL10 as a good substrate for MALT1. Conclusions We offered a way of monitoring the catalytic activity of MALT1 in HEK293T cells using BCL10GFP as a substrate. BCL10GFP can be utilized as a convenient tool for studying the determinants for efficient MALT1 cleavage in HEK293T cells

  17. In vitro developmental competence of pig nuclear transferred embryos: effects of GFP transfection, refrigeration, cell cycle synchronization and shapes of donor cells.

    Science.gov (United States)

    Zhang, Yun-Hai; Pan, Deng-Ke; Sun, Xiu-Zhu; Sun, Guo-Jie; Liu, Xiao-Hui; Wang, Xiao-Bo; Tian, Xing-Hua; Li, Yan; Dai, Yun-Ping; Li, Ning

    2006-08-01

    The present study was designed to evaluate the feasibility of producing pig transgenic blastocysts expressing enhanced green fluorescent protein (GFP) and to examine the effects of shape and preparation methods of donor cells on in vitro developmental ability of pig nuclear transferred embryos (NTEs). In experiment 1, the effect of GFP transfection on development of pig NTEs was evaluated. The cleavage and blastocyst rates showed no significant difference between NTEs derived from transfected and non-transfected donors. In experiment 2, the effect of different nuclear donor preparation methods on in vitro development of NTEs was examined. The cleavage rate showed no statistically significant differences among three preparation methods. The blastocyst rates of donor cells treated once at -4 degrees C and those of freshly digested cells were similar to each other (26.3% vs 17.9%). The lowest blastocyst rates (5.88%) were observed when cells cryopreserved at -196 degrees C were used as donors. In experiment 3, the effect of different cell cycle synchronization methods on the in vitro development potential of pig NTEs was evaluated. The cleavage rate of NTEs derived from cycling cells was much better than that of NTEs derived from serum-starved cells (64.4% vs 50.5%, p refrigerated pig GFP-transfected cells could be used as donors in nuclear transfer and these NTEs could be effectively developed to blastocyst stage; (ii) serum starvation of GFP-transfected cells is not required for preimplantation development of pig NTEs; and (iii) a rough surface of GFP-transfected donor cells affects fusion rate negatively but has no influence on the cleavage rate or blastocyst rate of pig NTEs.

  18. Therapeutic Effect and Location of GFP-Labeled Placental Mesenchymal Stem Cells on Hepatic Fibrosis in Rats

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    Jiong Yu

    2017-01-01

    Full Text Available Background. Liver fibrosis is a chronic progressive liver disease, but no established effective treatment exists except for liver transplantation. The present study was designed to investigate the effect of human placenta mesenchymal stem cells (hPMSCs expressing green fluorescent protein (GFP on carbon tetrachloride- (CCl4- induced liver fibrosis in rats. Methods. Liver fibrosis was induced by subcutaneous injection with CCl4; hPMSCs were directly transplanted into rats through the caudal vein. The therapeutic efficacy of hPMSCs on liver fibrosis was measured by liver function tests, liver elastography, histopathology, Masson’s trichrome and Sirius red staining, and immunohistochemical studies. The expression levels of fibrotic markers, transforming growth factor β1 (TGF-β1 and α-smooth muscle actin (α-SMA, were assessed using real-time polymerase chain reaction. Results. We demonstrated that liver fibrosis was significantly dampened in the hPMSC transplantation group according to the Laennec fibrosis scoring system and histological data. The Sirius red-stained collagen area and the elastography score were significantly reduced in the hPMSC-treated group. Meanwhile, hPMSC administration significantly decreased TGF-β1 and α-SMA expression and enhanced liver functions in CCl4-induced fibrotic rats. Conclusion. This study indicates that transplantation of hPMSCs could repair liver fibrosis induced by CCl4 in rats, which may serve as a valuable therapeutic approach to treat liver diseases.

  19. Potential utility of eGFP-expressing NOG mice (NOG-EGFP as a high purity cancer sampling system

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    Shima Kentaro

    2012-06-01

    Full Text Available Abstract Purpose It is still technically difficult to collect high purity cancer cells from tumor tissues, which contain noncancerous cells. We hypothesized that xenograft models of NOG mice expressing enhanced green fluorescent protein (eGFP, referred to as NOG-EGFP mice, may be useful for obtaining such high purity cancer cells for detailed molecular and cellular analyses. Methods Pancreato-biliary cancer cell lines were implanted subcutaneously to compare the tumorigenicity between NOG-EGFP mice and nonobese diabetic/severe combined immunodeficiency (NOD/SCID mice. To obtain high purity cancer cells, the subcutaneous tumors were harvested from the mice and enzymatically dissociated into single-cell suspensions. Then, the cells were sorted by fluorescence-activated cell sorting (FACS for separation of the host cells and the cancer cells. Thereafter, the contamination rate of host cells in collected cancer cells was quantified by using FACS analysis. The viability of cancer cells after FACS sorting was evaluated by cell culture and subsequent subcutaneous reimplantation in NOG-EGFP mice. Results The tumorigenicity of NOG-EGFP mice was significantly better than that of NOD/SCID mice in all of the analyzed cell lines (p  Conclusions This method provides a novel cancer sampling system for molecular and cellular analysis with high accuracy and should contribute to the development of personalized medicine.

  20. Using a GFP-gene fusion technique to study the cell cycle-dependent distribution of calmodulin in living cells

    Institute of Scientific and Technical Information of China (English)

    李朝军; 吕品; 张东才

    1999-01-01

    In this study, a green fluorescent protein (GFP)-calmodulin (CaM) fusion gene method was used to examine the distribution of calmodulin during various stages of cell cycle. First, it was found that the distribution of CaM in living cells changes with the cell cycle. CaM was found mainly in the cytoplasm during G1 phase. It began to move into the nucleus when the cell entered S phase. At G2 phase, CaM became more concentrated in the nucleus than in cytoplasm. Second, the accumulation of CaM in the nucleus during G2 phase appeared to be related to the onset of mitosis, since inhibiting the activation of CaM at this stage resulted in blocking the nuclear membrane breakdown and chromatin condensation. Finally, after the cell entered mitosis, a high concentration of CaM was found at the polar regions of the mitotic spindle. At this time, inhibiting the activity of CaM would cause a disruption of the spindle structure. The relationship between the stage-specific distribution of CaM and its function in regulat

  1. pIRES-GFP-前脑啡肽原载体在体内外的表达及生物学效应%Biological effect and expression of pIRES-GFP-preproenkephalin vector in vivo and vitro

    Institute of Scientific and Technical Information of China (English)

    刘雪琴; 胡伊乐; 郭绍芳; 任亚丽

    2013-01-01

    Objective To detect the expression of pIRES-GFP-preproenkephalin(PENK) vector in vivo and vitro in order to research the biological effect and the feasibility of clinical application of enkephalin gene.Methods Recombinant plasmid was constructed by connecting green fluorescence protein eukaryotic plasmid with the prepro-enkephalin gene of rats,and then the organism cells were transfected in vitro.The synthesis and expression of recombinant plasmid were observed by the expression level of the green fluorescence in positive cells and the radioimmunoassay of the content of enkephalin in the cell supernatants.The change of the rats' heat and pain threshold was observed by injecting recombinant plasmid of enkephalin in subarachnoid space of the rats to determine its biological activity of synthetic exogenous enkephalin in the body cells.Results The experiment in vitro showed green fluorescence of COS-7 cell expressed 24 hours after recombinant plasmidit transfection,reached peak in 48 hours and weakened in 27 days.The change of heat and pain threshold of the rats in animal experiment matched the effect of the vitro study.Conclusion The exogenous enkephalin,which is synthesized by recombinant plasmid in organism cells,possesses identical biological effect of endogenous enkephalin and can be used as a gene analgesic method of long-term in clinical application.%目的 检测pIRES-GFP-前脑啡肽原载体在体内外的表达,以探索脑啡肽基因镇痛的生物学效应与临床应用的可行性.方法 将大鼠前脑啡肽原基因与绿色荧光蛋白真核质粒连接构建重组质粒,体外转染机体细胞,通过阳性细胞绿色荧光表达的强弱与细胞上清液脑啡肽水平的放射免疫测定,观察重组质粒在细胞内的合成与表达;大鼠蛛网膜下腔注射重组质粒,观察大鼠热痛阈值的变化,确定重组质粒在机体细胞内合成外源性脑啡肽的生物学活性.结果 体外试验表明重组质粒转染24 h后COS-7

  2. A VIN1 GUS::GFP fusion reveals activated sucrose metabolism programming occurring in interspersed cells during tomato fruit ripening.

    Science.gov (United States)

    Estornell, Leandro Hueso; Pons, Clara; Martínez, Alicia; O'Connor, José Enrique; Orzaez, Diego; Granell, Antonio

    2013-08-15

    The tomato is a model for fleshy fruit development and ripening. Here we report on the identification of a novel unique cell autonomous/cellular pattern of expression that was detected in fruits of transgenic tomato lines carrying a GFP GUS driven by the fruit specific vacuolar invertase promoter VIN1. The VIN1 promoter sequence faithfully reproduced the global endogenous VIN expression by conferring a biphasic pattern of expression with a second phase clearly associated to fruit ripening. A closer view revealed a salt and pepper pattern of expression characterized by individual cells exhibiting a range of expression levels (from high to low) surrounded by cells with no expression. This type of pattern was detected across different fruit tissues and cell types with some preferences for vascular, sub-epidermal layer and the inner part of the fruit. Cell ability to show promoter activity was neither directly associated with overall ripening - as we find VIN+ and - VIN- cells at all stages of ripening, nor with cell size. Nevertheless the number of cells with active VIN-driven expression increased with ripening and the activity of the VIN promoter seems to be inversely correlated with cell size in VIN+ cells. Gene expression analysis of FACS-sorted VIN+ cells revealed a transcriptionally distinct subpopulation of cells defined by increased expression of genes related to sucrose metabolism, and decreased activity in protein synthesis and chromatin remodeling. This finding suggests that local micro heterogeneity may underlie some aspects (i.e. the futile cycles involving sucrose metabolism) of an otherwise more uniform looking ripening program.

  3. A GFP-Tagged Gross Deletion on Chromosome 1 Causes Malignant Peripheral Nerve Sheath Tumors and Carcinomas in Zebrafish.

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    Matteo Astone

    Full Text Available Malignant peripheral nerve sheath tumors (MPNSTs are highly aggressive soft-tissue sarcomas, characterized by complex karyotypes. The molecular bases of such malignancy are poorly understood and efficient targeted molecular therapies are currently lacking. Here we describe a novel zebrafish model of MPNSTs, represented by the transgenic mutant line Tg(-8.5nkx2.2a:GFPia2. ia2 homozygous animals displayed embryonic lethality by 72 hpf, while the heterozygotes develop visible tumor masses with high frequency in adulthood. Histological and immunohistochemical examination revealed aggressive tumors with either mesenchymal or epithelial features. The former (54% of the cases arose either in the abdominal cavity, or as intrathecal/intraspinal lesions and is composed of cytokeratin-negative spindle cells with fascicular/storiform growth pattern consistent with zebrafish MPNSTs. The second histotype was composed by polygonal or elongated cells, immunohistochemically positive for the pan-cytokeratin AE1/AE3. The overall histologic and immunohistochemical features were consistent with a malignant epithelial neoplasm of possible gastrointestinal/pancreatic origin. With an integrated approach, based on microsatellite (VNTR and STS markers, we showed that ia2 insertion, in Tg(-8.5nkx2.2a:GFPia2 embryos, is associated with a deletion of 15.2 Mb in the telomeric portion of chromosome 1. Interestingly, among ia2 deleted genes we identified the presence of the 40S ribosomal protein S6 gene that may be one of the possible drivers for the MPNSTs in ia2 mutants. Thanks to the peculiar features of zebrafish as animal model of human cancer (cellular and genomic similarity, transparency and prolificacy and the GFP tag, the Tg(-8.5nkx2.2a:GFPia2 line provides a manageable tool to study in vivo with high frequency MPNST biology and genetics, and to identify, in concert with the existing zebrafish MPNST models, conserved relevant mechanisms in zebrafish and human cancer

  4. Development of a new "GFP hop-on assay" system for insertion sequence transposition in Bacillus subtilis 168 using IS4Bsu1 from B. subtilis (natto).

    Science.gov (United States)

    Takahashi, Kiwamu; Chibazakura, Taku; Sekine, Yasuhiko; Yoshikawa, Hirofumi

    2007-04-06

    While most studies involving transposition have focused on analyzing the detailed mechanisms of transposition, the cellular conditions under which transposition occurs remain to be elucidated. In Escherichia coli, papillation assay is a powerful tool for transpositional analysis and the isolation of mutants affecting transposition. On the other hand, while our assay system based on the E. coli papillation assay can detect transpositional events in Bacillus subtilis 168, it is not suitable for quantitating transposition frequency because blue papillae on the transposant colonies of B. subtilis are not countable. We succeeded in developing a new "GFP hop-on assay" system that facilitates quantitative detection of the transposition of the FACS-optimized GFP mutant gene. Our assay system is a step forward in understanding the cellular conditions under which transposition occurs.

  5. A set of GFP-based organelle marker lines combined with DsRed-based gateway vectors for subcellular localization study in rice (Oryza sativa L.).

    Science.gov (United States)

    Wu, Tsung-Meng; Lin, Ke-Chun; Liau, Wei-Shiang; Chao, Yun-Yang; Yang, Ling-Hung; Chen, Szu-Yun; Lu, Chung-An; Hong, Chwan-Yang

    2016-01-01

    In the post-genomic era, many useful tools have been developed to accelerate the investigation of gene functions. Fluorescent proteins have been widely used as protein tags for studying the subcellular localization of proteins in plants. Several fluorescent organelle marker lines have been generated in dicot plants; however, useful and reliable fluorescent organelle marker lines are lacking in the monocot model rice. Here, we developed eight different GFP-based organelle markers in transgenic rice and created a set of DsRed-based gateway vectors for combining with the marker lines. Two mitochondrial-localized rice ascorbate peroxidase genes fused to DsRed and successfully co-localized with mitochondrial-targeted marker lines verified the practical use of this system. The co-localization of GFP-fusion marker lines and DsRed-fusion proteins provide a convenient platform for in vivo or in vitro analysis of subcellular localization of rice proteins.

  6. POTENTIAL APPLICATIONS OF SOS-GFP BIOSENSOR TO IN VITRO RAPID SCREENING OF CYTOTOXIC AND GENOTOXIC EFFECT OF ANTICANCER AND ANTIDIABETIC PHARMACIST RESIDUES IN SURFACE WATER

    Directory of Open Access Journals (Sweden)

    Marzena Matejczyk

    2014-12-01

    Full Text Available Escherichia coli K-12 GFP-based bacterial biosensors allowed the detection of cytotoxic and genotoxic effect of anticancer drug– cyclophosphamide and antidiabetic drug – metformin in PBS buffer and surface water. Experimental data indicated that recA::gfpmut2 genetic system was sensitive to drugs and drugs mixture applied in experiment. RecA promoter was a good bioindicator in cytotoxic and genotoxic effect screening of cyclophosphamide, metformin and the mixture of the both drugs in PBS buffer and surface water. The results indicated that E. coli K-12 recA::gfp mut2 strain could be potentially useful for first-step screening of cytotoxic and genotoxic effect of anticancer and antidiabetic pharmacist residues in water. Next steps in research will include more experimental analysis to validate recA::gfpmut2 genetic system in E. coli K-12 on different anticancer drugs.

  7. Shh pathway in wounds in non-diabetic Shh-Cre-eGFP/Ptch1-LacZ mice treated with MAA beads.

    Science.gov (United States)

    Lisovsky, Alexandra; Sefton, Michael V

    2016-09-01

    Previously, poly(methacrylic acid-co-methyl methacrylate) (MAA) beads were shown to improve vessel formation with a concomitant increase in the expression of the sonic hedgehog (Shh) gene, a pleiotropic factor implicated in vascularization. The aim of this study was to follow up on this observation in the absence of the confounding factors of diabetes in non-diabetic Shh-Cre-eGFP/Ptch1-LacZ mice; in this mouse, expression of GFP and β-Gal is consistent with the transcription patterns of Shh and its receptor patched 1 (Ptch1), respectively. In agreement with studies in diabetic males, MAA beads improved vascularization in large (15 mm × 15 mm) wounds in non-diabetic males at day 7. Shh pathway activation was suggested, as the numbers of GFP+ (Shh) and β-Gal+ (Ptch1, a target of the pathway) cells increased in the granulation tissue. Shh signaling pathway modulation was also suggested in the healthy skin surrounding the wound bed, as evidenced by an increase in the number of GFP+ and β-Gal+ cells in males at day 4. Gene expression analysis of the wounds confirmed increase in Ptch1 and showed the upregulation of a downstream transcription factor Gli3, involved in the vascular effect of the Shh pathway, implicating the pathway in the effect of MAA beads. The efficacy of MAA beads was also investigated in females; MAA beads modulated the Shh pathway within granulation tissue similarly as in males, but had no enhancement effect on the healthy skin and on vascularization. We believe that understanding the molecular and cellular mechanisms of MAA-based biomaterials and testing the efficacy of therapeutics in both sexes will inform the development of novel therapeutic biomaterials.

  8. Quantification of induced resistance against Phytophthora species expressing GFP as a vital marker: beta-aminobutyric acid but not BTH protects potato and Arabidopsis from infection.

    Science.gov (United States)

    Si-Ammour, Azeddine; Mauch-Mani, Brigitte; Mauch, Felix

    2003-07-01

    SUMMARY Induced resistance was studied in the model pathosystem Arabidopsis-Phytophthora brassicae (formerly P. porri) in comparison with the agronomically important late blight disease of potato caused by Phytophthora infestans. For the quantification of disease progress, both Phytophthora species were transformed with the vector p34GFN carrying the selectable marker gene neomycine phosphotransferase (nptII) and the reporter gene green fluorescent protein (gfp). Eighty five per cent of the transformants of P. brassicae and P. infestans constitutively expressed GFP at high levels at all developmental stages both in vitro and in planta. Transformants with high GFP expression and normal in vitro growth and virulence were selected to quantify pathogen growth by measuring the in planta emitted GFP fluorescence. This non-destructive monitoring of the infection process was applied to analyse the efficacy of two chemical inducers of disease resistance, a functional SA-analogue, benzothiadiazole (BTH), and beta-aminobutyric acid (BABA) which is involved in priming mechanisms of unknown nature. BABA pre-treatment (300 microm) via soil drench applied 24 h before inoculation completely protected the susceptible Arabidopsis accession Landsberg erecta (Ler) from infection with P. brassicae. A similar treatment with BTH (330 microm) did not induce resistance. Spraying the susceptible potato cultivar Bintje with BABA (1 mm) 2 days before inoculation resulted in a phenocopy of the incompatible interaction shown by the resistant potato cultivar Matilda while BTH (1.5 mm) did not protect Bintje from severe infection. Thus, in both pathosystems, the mechanisms of induced resistance appeared to be similar, suggesting that the Arabidopsis-P. brassicae pathosystem is a promising model for the molecular analysis of induced resistance mechanisms of potato against the late blight disease.

  9. Generation of GFAP::GFP astrocyte reporter lines from human adult fibroblast-derived iPS cells using zinc-finger nuclease technology.

    Science.gov (United States)

    Zhang, Ping-Wu; Haidet-Phillips, Amanda M; Pham, Jacqueline T; Lee, Youngjin; Huo, Yuqing; Tienari, Pentti J; Maragakis, Nicholas J; Sattler, Rita; Rothstein, Jeffrey D

    2016-01-01

    Astrocytes are instrumental to major brain functions, including metabolic support, extracellular ion regulation, the shaping of excitatory signaling events and maintenance of synaptic glutamate homeostasis. Astrocyte dysfunction contributes to numerous developmental, psychiatric and neurodegenerative disorders. The generation of adult human fibroblast-derived induced pluripotent stem cells (iPSCs) has provided novel opportunities to study mechanisms of astrocyte dysfunction in human-derived cells. To overcome the difficulties of cell type heterogeneity during the differentiation process from iPSCs to astroglial cells (iPS astrocytes), we generated homogenous populations of iPS astrocytes using zinc-finger nuclease (ZFN) technology. Enhanced green fluorescent protein (eGFP) driven by the astrocyte-specific glial fibrillary acidic protein (GFAP) promoter was inserted into the safe harbor adeno-associated virus integration site 1 (AAVS1) locus in disease and control-derived iPSCs. Astrocyte populations were enriched using Fluorescence Activated Cell Sorting (FACS) and after enrichment more than 99% of iPS astrocytes expressed mature astrocyte markers including GFAP, S100β, NFIA and ALDH1L1. In addition, mature pure GFP-iPS astrocytes exhibited a well-described functional astrocytic activity in vitro characterized by neuron-dependent regulation of glutamate transporters to regulate extracellular glutamate concentrations. Engraftment of GFP-iPS astrocytes into rat spinal cord grey matter confirmed in vivo cell survival and continued astrocytic maturation. In conclusion, the generation of GFAP::GFP-iPS astrocytes provides a powerful in vitro and in vivo tool for studying astrocyte biology and astrocyte-driven disease pathogenesis and therapy.

  10. Modification of Superoxide Dismutase 1 (SOD1) Properties by a GFP Tag – Implications for Research into Amyotrophic Lateral Sclerosis (ALS)

    OpenAIRE

    Stevens, James C.; Ruth Chia; Hendriks, William T.; Virginie Bros-Facer; Jan van Minnen; Joanne E Martin; Jackson, Graham S.; Linda Greensmith; Giampietro Schiavo; Elizabeth M. C. Fisher

    2010-01-01

    BACKGROUND: Since the discovery that mutations in the enzyme SOD1 are causative in human amyotrophic lateral sclerosis (ALS), many strategies have been employed to elucidate the toxic properties of this ubiquitously expressed mutant protein, including the generation of GFP-SOD1 chimaeric proteins for studies in protein localization by direct visualization using fluorescence microscopy. However, little is known about the biochemical and physical properties of these chimaeric proteins, and whet...

  11. Design and Construction of ctxB-gfp-stxB Gene Cassette and Investigation of Its Expression in E. coli Bl21 (DE3

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    Aghil Esmaeili

    2013-06-01

    Full Text Available Background & Objective: In order to enhance the expression of soluble proteins and facilitate their purification and development of multi-functional polypeptide , chimerical recombinant proteins have been invented . The purpose of this study was to construct ctxB-gfp-stxB gene cassette to measure the uptake and excretion of chimerical antigen in future studies.   Materials & Methods: After preparation of primers for gfp gene as a reporter gene , ctxB and stxB, attempts were made to amplify the genes via the PCR techniques . The amplified genes were clone d in the pGEM vector; and after confirmation of the gene fragments, they were fused as ctxB-gfp-stxB. The gene cassette was thereafter sub-cloned in the pET28a(+ expression vector. E. coli Bl21 (DE3 was transformed by the recombinant vector pET28a(+, and the expression of the recombinant protein was investigated by IPTG induction and SDS-PAGEelectrophoresis.   Results: The amplified genes were cloned in the pGEM vector, and were confirmed via PCR, restriction enzymes, and sequence analyzing system. The confirmed gene fragments were mixed together as ctxB-gfp-stxB . The existence of the gene cassette was confirmed after sub-cloning. The expression was not observed for this gene cassette in E . coli.   Conclusion: The presence of a large number of E. coli rare codons in ctxB and stxB gene sequences precluded the expression of the gene cassette in E. coli; it, therefore, requires the discovery of a suitable host cell for its expression and optimization. Given the gene cassette structure and position of restriction enzymes on the constructed fragment, this gene can be replaced with different genes and can produce a variety of gene fragments.

  12. A germline GFP transgenic axolotl and its use to track cell fate: dual origin of the fin mesenchyme during development and the fate of blood cells during regeneration.

    Science.gov (United States)

    Sobkow, Lidia; Epperlein, Hans-Henning; Herklotz, Stephan; Straube, Werner L; Tanaka, Elly M

    2006-02-15

    The development of transgenesis in axolotls is crucial for studying development and regeneration as it would allow for long-term cell fate tracing as well as gene expression analysis. We demonstrate here that plasmid injection into the one-cell stage axolotl embryo generates mosaic transgenic animals that display germline transmission of the transgene. The inclusion of SceI meganuclease in the injections (Thermes, V., Grabher, C., Ristoratore, F., Bourrat, F., Choulika, A., Wittbrodt, J., Joly, J.S., 2002. I-SceI meganuclease mediates highly efficient transgenesis in fish. Mech. Dev. 118, 91-98) resulted in a higher percentage of F0 animals displaying strong expression throughout the body. This represents the first demonstration in the axolotl of germline transmission of a transgene. Using this technique we have generated a germline transgenic animal expressing GFP ubiquitously in all tissues examined. We have used this animal to study cell fate in the dorsal fin during development. We have uncovered a contribution of somite cells to dorsal fin mesenchyme in the axolotl, which was previously assumed to derive solely from neural crest. We have also studied the role of blood during tail regeneration by transplanting the ventral blood-forming region from GFP+ embryos into unlabeled hosts. During tail regeneration, we do not observe GFP+ cells contributing to muscle or nerve, suggesting that during tail regeneration blood stem cells do not undergo significant plasticity.

  13. Detection and characterization of N-acyl-l-homoserine lactones using GFP-based biosensors in conjunction with thin-layer chromatography.

    Science.gov (United States)

    Charlesworth, James; Kimyon, Onder; Manefield, Michael; Burns, Brendan P

    2015-11-01

    Many microorganisms use quorum sensing to regulate several complex phenotypes, and this is accomplished by the release of a signal molecule(s) into the environment. N-acyl-homoserine lactones (AHLs) are a common class of signalling molecule utilized by a range of microorganisms (primarily Gram negative bacteria but most recently also archaea) and are often detected through the use of bacterial biosensors. Biosensors can be limited by both their specificity and sensitivity, and the aim of this study was to modify and improve current AHL detection strategies. The biosensor employed in the present study was Escherichia coli MT102 harbouring a plasmid containing a LuxR based biosensor, which produces green fluorescent protein (GFP) as a reporting mechanism. A new method of visualizing the GFP based biosensor overlaid on silica sheets for the purpose of thin-layer chromatography (TLC) is presented. This new method vastly improves sensitivity of AHL detection by a GFP biosensor than previously reported and as such represents a powerful new tool in AHL research. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. Early Identification of Stable Transformation Events by Combined Use of Antibiotic Selection and Vital Detection of Green Fluorescent Protein (GFP) in Carrot (Daucus carota L.) Callus

    Institute of Scientific and Technical Information of China (English)

    Yuan-Yeu Yau; Seth J Davis; Ahmet Ipek; Philipp W Simon

    2008-01-01

    Genetic transformation is a useful technique to complement conventional breeding in crop improvement. Although carrot has been a model organism for in vitro embryogenesis study, genetic transformation of carrot is still lengthy and labor intensive. An efficient transformation and detection system is desirable. Direct infection of Agrobacterium to carrot calli has provided an easy way for carrot genetic transformation. To improve the efficiency of antibiotic selection in this method, we report the combined use of an improved green-fluorescent protein, referred to as smGFP, to establish a versatile selection method for carrot callus transformation system. By combining antibiotic selection with the bright fluorescence observed in the callus tissue, we were able to easily identify stable transformants in early stage of the transformation process. In addition to the GFP expression of the callus cells, the transgenic nature of callus cells was confirmed with Southern and Western analysis. We found we can link the simplicity of carrot-callus-cell transformation, early detection of stable transformants with antibiotic selection, visualization of GFP fluorescence, and molecular analysis (Southern and Western) of callus tissue (non-photosynthetic tissue) to provide a more efficient way in identifying stable transformants at early stage of carrot transformation.

  15. Diffusion behavior of the fluorescent proteins eGFP and Dreiklang in solvents of different viscosity monitored by fluorescence correlation spectroscopy

    Science.gov (United States)

    Junghans, Cornelia; Schmitt, Franz-Josef; Vukojević, Vladana; Friedrich, Thomas

    2016-12-01

    Fluorescence correlation spectroscopy relies on temporal autocorrelation analysis of fluorescence intensity fluctuations that spontaneously arise in systems at equilibrium due to molecular motion and changes of state that cause changes in fluorescence, such as triplet state transition, photoisomerization and other photophysical transformations, to determine the rates of these processes. The stability of a fluorescent molecule against dark state conversion is of particular concern for chromophores intended to be used as reference tags for comparing diffusion processes on multiple time scales. In this work, we analyzed properties of two fluorescent proteins, the photoswitchable Dreiklang and its parental eGFP, in solvents of different viscosity to vary the diffusion time through the observation volume element by several orders of magnitude. In contrast to eGFP, Dreiklang undergoes a dark-state conversion on the time scale of tens to hundreds of microseconds under conditions of intense fluorescence excitation, which results in artificially shortened diffusion times if the diffusional motion through the observation volume is sufficiently slowed down. Such photophysical quenching processes have also been observed in FCS studies on other photoswitchable fluorescent proteins including Citrine, from which Dreiklang was derived by genetic engineering. This property readily explains the discrepancies observed previously between the diffusion times of eGFP- and Dreiklang-labeled plasma membrane protein complexes.

  16. Toward a rationale for the PTC124 (Ataluren) promoted readthrough of premature stop codons: a computational approach and GFP-reporter cell-based assay.

    Science.gov (United States)

    Lentini, Laura; Melfi, Raffaella; Di Leonardo, Aldo; Spinello, Angelo; Barone, Giampaolo; Pace, Andrea; Palumbo Piccionello, Antonio; Pibiri, Ivana

    2014-03-03

    The presence in the mRNA of premature stop codons (PTCs) results in protein truncation responsible for several inherited (genetic) diseases. A well-known example of these diseases is cystic fibrosis (CF), where approximately 10% (worldwide) of patients have nonsense mutations in the CF transmembrane regulator (CFTR) gene. PTC124 (3-(5-(2-fluorophenyl)-1,2,4-oxadiazol-3-yl)-benzoic acid), also known as Ataluren, is a small molecule that has been suggested to allow PTC readthrough even though its target has yet to be identified. In the lack of a general consensus about its mechanism of action, we experimentally tested the ability of PTC124 to promote the readthrough of premature termination codons by using a new reporter. The reporter vector was based on a plasmid harboring the H2B histone coding sequence fused in frame with the green fluorescent protein (GFP) cDNA, and a TGA stop codon was introduced in the H2B-GFP gene by site-directed mutagenesis. Additionally, an unprecedented computational study on the putative supramolecular interaction between PTC124 and an 11-codon (33-nucleotides) sequence corresponding to a CFTR mRNA fragment containing a central UGA nonsense mutation showed a specific interaction between PTC124 and the UGA codon. Altogether, the H2B-GFP-opal based assay and the molecular dynamics (MD) simulation support the hypothesis that PTC124 is able to promote the specific readthrough of internal TGA premature stop codons.

  17. Chitosan-gelatin scaffolds for tissue engineering: physico-chemical properties and biological response of buffalo embryonic stem cells and transfectant of GFP-buffalo embryonic stem cells.

    Science.gov (United States)

    Thein-Han, W W; Saikhun, J; Pholpramoo, C; Misra, R D K; Kitiyanant, Y

    2009-11-01

    The favorable cellular response of newly developed cell line, buffalo embryonic stem (ES) cells to three-dimensional biodegradable chitosan-gelatin composite scaffolds with regard to stem-cell-based tissue engineering is described. Chitosan-gelatin composites were characterized by a highly porous structure with interconnected pores, and the mechanical properties were significantly enhanced. Furthermore, X-ray diffraction study indicated increased amorphous content in the scaffold on the addition of gelatin to chitosan. To develop a transfectant of green fluorescence protein (GFP)-buffalo ES cell, transfection of GFP plasmid to the cell was carried out via the electroporation procedure. In comparison with pure chitosan, cell spreading and proliferation were greater in highly visualized GFP-expressing cell-chitosan-gelatin scaffold constructs. The relative comparison of biological response involving cell proliferation and viability on the scaffolds suggests that blending of gelatin in chitosan improved cellular efficiency. Studies involving scanning electron and fluorescence microscopy, histological observations and flow cytometer analysis of the constructs implied that the polygonal cells attached to and penetrated the pores, and proliferated well, while maintaining their pluripotency during the culture period for 28days. Chitosan-gelatin scaffolds were cytocompatible with respect to buffalo ES cells. The study underscores for the first time that chitosan-gelatin scaffolds are promising candidates for ES-cell-based tissue engineering.

  18. Transformation of Arabidopsis by Rice OsWRKY78:: GFP Fusion Gene and Subcellular Localization of OsWRKY78 Protein

    Institute of Scientific and Technical Information of China (English)

    Shunzhi LIU; Mei ZHANG; Xin TANG; Xiaolan WANG

    2012-01-01

    [Objective] The study was to understand the subcellular localization of OsWRKY78 protein in plants. [Method] Primers specific for OsWRKY78 gene were designed according to the OsWRKY78 full length sequence in Genbank. The gene was cloned by RT-PCR method. The gene was then recombined into a plasmid ex- pression vector carrying green fluorescent protein (GFP) gene, pBinGFP. The re- combinant was confirmed by PCR and enzyme digestion. The recombinant plasmid pBinGFP-OsWRKY was transformed into Arabidopsis through Agrobacterium tume- faciens strain GV3101 and transgenic plants were obtained. [Result] Measured by fluorescence microscopy, the expression of OsWRKY78 and GFP fusion protein in root tip cells was localized in the nucleus. [Conclusion] This study laid the foundation for further investigating the function of OsWRKY78 gene and its role in related sig- nal transduction and provided theoretical basis for exploring the relation between OsWRKY78 gene and brown planthoppers.

  19. Construction and Application of a Gateway Entry Vector pEN-L4*-PrbcS-*T-gfp-L3*%通路克隆入门载体pEN-L4*-PrbcS-*T-gfp-L3*的构建及其应用

    Institute of Scientific and Technical Information of China (English)

    肖素勤; 孙振; 王莎莎; 梁锋; 李莉; 年洪娟; 李昆志; 陈丽梅

    2011-01-01

    In order to construct the plant expression vector that contains two expression cassettes for two target genes through a Gateway LR recombination reaction and allows the expressed proteins encoded by the target genes to be localized to the chloroplasts of transgenic plants, Hind III and Xho I sites were generated in the Gateway entry vector, pEN-L4-2-L3, through a quickChange site-directed mutagenesis technology. Then a DNA fragment containing the tomato Rubisco small subunit 3C promoter (PrbcS) and its transit pep-tide sequence (*T) as well as a GFP (Green fluorescent protein) reporter gene (gfp) was inserted in the modified entry vector between the Hind III and Xho I sites to develop the entry vector pEN-L4*-PrbcS-*T-gfp-L3*. The plant expression vector pKm-35S-PrbcS-*T-gfp-PROLD-PrbcS-*T-gus containing the expression cassettes of gfp and gus genes could be constructed successfully with the developed entry vector pEN-L4*-PrbcS-*T-gfp-L3* and another Gateway entry vector (pENTR*-PrbcS-*T-gus) that contains attLl and attL2recombination sites as well as the plant destination vector pK7 m34GW2-8 m21GW3 through a Gateway LR reaction. Gfp and gus genes could be inserted in the genome of the transgenic plants and transcribed normally after the pKm-35S-PrbcS-*T-gfp-PROLD-PrbcS-*T-gus vector was used to transform tobacco. The analysis of GUS staining and GFP localization indicated that the GUS protein was expressed in the transgenic tobacco leaves and the expressed GFP protein was targeted to the chloroplasts of the leaves. Using the expression vector can not only complete the genetic manipulation of two target genes through one transformation but also locate the expressed proteins regulated by PrbcS promoter to the transgenic plant chloroplasts via the transit peptide sequence (*T). As a result, the construction and application of pEN-LA*-PibcS-*T-gfp-L3* entry vector establishes a technique platform and provides the convenience for chloroplast genetic engineering.%为

  20. クミカエ GFP リョクショク ケイコウ タンパクシツ オ モチイタ タンパクシツ ノ ガクシュウ プログラム ノ カイハツ

    OpenAIRE

    石澤, 公明; 知識, 麻友子

    2009-01-01

    Green Fluorescent Protein (GFP) is a protein purified from the jellyfish, Aequorea victoria. The modifiedGFP gene has been inserted into pGLO plasmid and now is available from Bio-Rad Laboratories for educationalapplication of studies on biotechnology or molecular biology. Recombinant GFP expressed in E.coli transformedwith pGLO is a highly potent tool for "protein literacy". We proposed an experimental protocol constituted of afew GFP purification methods, which are useful for high-school st...

  1. Evaluation of the effects of ethinylestradiol on sexual differentiation in the olvas-GFP/STII-YI medaka (transgenic Oryzias latipes) strain as estimated by proliferative activity of germ cells

    Energy Technology Data Exchange (ETDEWEB)

    Hano, Takeshi [National Research Institute of Fisheries and Environment of Inland Sea, Fisheries Research Agency, 2-17-5 Maruishi, Hatsukaichi, Hiroshima 739-0452 (Japan); Laboratory of Marine Environmental Science, Faculty of Agriculture, Kyushu University, Hakozaki 6-10-1, Higashi-ku, Fukuoka 812-8581 (Japan); Oshima, Yuji, E-mail: yoshima@agr.kyushu-u.ac.jp [Laboratory of Marine Environmental Science, Faculty of Agriculture, Kyushu University, Hakozaki 6-10-1, Higashi-ku, Fukuoka 812-8581 (Japan); Kinoshita, Masato [Division of Applied Biosciences, Graduate School of Agriculture, Kyoto University, Kitashirakawa-Oiwake-cho, Sakyo-ku, Kyoto 606-8502 (Japan); Tanaka, Minoru [Laboratory of Molecular Genetics for Reproduction, National Institute for Basic Biology, Nishigonaka 38, Myodaiji, Okazaki 444-8585 Aichi (Japan); Mishima, Noriko; Wakamatsu, Yuko; Ozato, Kenjiro [Laboratory of Freshwater Fish Stocks, Bioscience and Biotechnology Center, Nagoya University Furo-cho, Chikusa-ku, Nagoya 464-8601 (Japan); Shimasaki, Yohei; Honjo, Tsuneo [Laboratory of Marine Environmental Science, Faculty of Agriculture, Kyushu University, Hakozaki 6-10-1, Higashi-ku, Fukuoka 812-8581 (Japan)

    2011-08-15

    We evaluated the effects of 17(-ethinylestradiol (EE{sub 2}) on sexual differentiation in transgenic olvas-GFP/STII-YI medaka (Oryzias latipes) in terms of the proliferative activity of germ cells. This strain contains the green fluorescent protein (GFP) gene fused to the regulatory region of the medaka vasa gene, and germ cell-specific expression of GFP can be visualized in living (transparent) individuals. From 0 days post-hatch (0 dph) onwards, juveniles were exposed to graded concentrations of EE{sub 2} (25.2-1710 ng/L) for 35 days. The gonads of live specimens were monitored by measuring their size and calculating their GFP-fluorescence area. GFP-fluorescent area in control females was about 10 times that in control males at 10 days posthatch (dph) whereas the gonadal size of 10 dph males that had been exposed to 158 ng/L of EE{sub 2} significantly increased up to twice the size of control males, indicating that abnormal sexual differentiation towards female might occur in these individuals. Histological examination and identification of the sex-linked marker SL1 indicated that male to female sex reversal occurred at EE{sub 2} exposure {>=}45.1 ng/L at 35 dph. These results suggest that observation of proliferative activity of germ cells in the olvas-GFP/STII-YI strain could be applied to facilitated screening fish model to detect adverse effects on sexual differentiation as early as 10 dph juveniles.

  2. Overexpression of the Synthetic Chimeric Native-T-phylloplanin-GFP Genes Optimized for Monocot and Dicot Plants Renders Enhanced Resistance to Blue Mold Disease in Tobacco (N. tabacum L.

    Directory of Open Access Journals (Sweden)

    Dipak K. Sahoo

    2014-01-01

    Full Text Available To enhance the natural plant resistance and to evaluate the antimicrobial properties of phylloplanin against blue mold, we have expressed a synthetic chimeric native-phylloplanin-GFP protein fusion in transgenic Nicotiana tabacum cv. KY14, a cultivar that is highly susceptible to infection by Peronospora tabacina. The coding sequence of the tobacco phylloplanin gene along with its native signal peptide was fused with GFP at the carboxy terminus. The synthetic chimeric gene (native-phylloplanin-GFP was placed between the modified Mirabilis mosaic virus full-length transcript promoter with duplicated enhancer domains and the terminator sequence from the rbcSE9 gene. The chimeric gene, expressed in transgenic tobacco, was stably inherited in successive plant generations as shown by molecular characterization, GFP quantification, and confocal fluorescent microscopy. Transgenic plants were morphologically similar to wild-type plants and showed no deleterious effects due to transgene expression. Blue mold-sensitivity assays of tobacco lines were performed by applying P. tabacina sporangia to the upper leaf surface. Transgenic lines expressing the fused synthetic native-phyllopanin-GFP gene in the leaf apoplast showed resistance to infection. Our results demonstrate that in vivo expression of a synthetic fused native-phylloplanin-GFP gene in plants can potentially achieve natural protection against microbial plant pathogens, including P. tabacina in tobacco.

  3. Unveiling how an archetypal fluorescent protein operates: theoretical perspective on the ultrafast excited state dynamics of GFP variant S65T/H148D.

    Science.gov (United States)

    Armengol, Pau; Gelabert, Ricard; Moreno, Miquel; Lluch, José M

    2015-02-12

    Green fluorescent protein variant S65T/H148D has been reported to host a photocycle involving the photoinduced proton transfer reaction between the chromophore and residue Asp148 under 50 fs and without a measurable kinetic isotope effect, and experimental evidence is suggestive of the existence of a highly delocalized proton between these residues. The blinding speed at which this biological system undergoes proton transfer has been ascribed to the extreme increase of acidity of the GFP chromophore in the electronic excited state where proton transfer takes place. This work strives to present a coherent, complete, and balanced description of the dynamics of this specific variant of GFP in which it will be shown that this increase of acidity is insufficient to explain the behavior observed. This study tracks the behavior of this photosystem to the delicate interplay between structure and dynamics shown in the presence of solvent. In this way, it has been found that the dynamics of this protein intertwines its structure with the intervening solvent to give rise to effectively degenerate situations in what concerns the reactants and products of the proton transfer reaction in ground and, most importantly, photoexcited state, in terms of potential energy profiles associated with the proton migration. Under these conditions, proton transfer can occur in accordance with the experimental data available. This set of characteristics is possibly common to a host of other proton transfer based fluorescent proteins, and helps promoting GFP S65T/H148D to a case of archetypal significance. Thus, our results can be useful to understand the way many fluorescent proteins work and, more generally, the molecular basis for proton transfer reactions in proteins.

  4. Use of RNAlater in fluorescence-activated cell sorting (FACS reduces the fluorescence from GFP but not from DsRed

    Directory of Open Access Journals (Sweden)

    Epstein Miles L

    2010-12-01

    Full Text Available Abstract Background Flow cytometry utilizes signals from fluorescent markers to separate targeted cell populations for gene expression studies. However, the stress of the FACS process could change normal gene expression profiles. RNAlater could be used to stop such changes in original gene expression profiles through its ability to denature RNase and other proteins. The normal conformational structure of fluorescent proteins must be maintained in order to fluoresce. Whether or not RNAlater would affect signals from different types of intrinsic fluorescent proteins is crucial to its use in flow cytometry; this question has not been investigated in detail. Findings To address this question, we analyzed the effect of RNAlater on fluorescence intensity of GFP, YFP, DsRed and small fluorescent molecules attached to secondary antibodies (Cy2 and Texas-Red when used in flow cytometry. FACS results were confirmed with fluorescence microscopy. Our results showed that exposure of YFP and GFP containing cells to RNAlater reduces the intensity of their fluorescence to such an extent that separation of such labeled cells is difficult if not impossible. In contrast, signals from DsRed2, Cy2 and Texas-Red were not affected by RNAlater treatment. In addition, the background fluorescence and clumping of dissociated cells are altered by RNAlater treatment. Conclusions When considering gene expression studies using cell sorting with RNAlater, DsRed is the fluorescent protein of choice while GFP/YFP have severe limitations because of their reduced fluorescence. It is necessary to examine the effects of RNAlater on signals from fluorescent markers and the physical properties (e.g., clumping of the cells before considering its use in cell sorting.

  5. Identification of the MUC2 Promoter as a Strong Promoter for Intestinal Gene Expression through Generation of Transgenic Quail Expressing GFP in Gut Epithelial Cells

    Directory of Open Access Journals (Sweden)

    Rachel M. Woodfint

    2017-01-01

    Full Text Available Identification of tissue- and stage-specific gene promoters is valuable for delineating the functional roles of specific genes in genetically engineered animals. Here, through the comparison of gene expression in different tissues by analysis of a microarray database, the intestinal specificity of mucin 2 (MUC2 expression was identified in mice and humans, and further confirmed in chickens by RT-PCR (reverse transcription-PCR analysis. An analysis of cis-acting elements in avian MUC2 gene promoters revealed conservation of binding sites, within a 2.9 kb proximal promoter region, for transcription factors such as caudal type homeobox 2 (CDX2, GATA binding protein 4 (GATA4, hepatocyte nuclear factor 4 α (HNF4A, and transcription factor 4 (TCF4 that are important for maintaining intestinal homeostasis and functional integrity. By generating transgenic quail, we demonstrated that the 2.9 kb chicken MUC2 promoter could drive green fluorescent protein (GFP reporter expression exclusively in the small intestine, large intestine, and ceca. Fluorescence image analysis further revealed GFP expression in intestine epithelial cells. The GFP expression was barely detectable in the embryonic intestine, but increased during post-hatch development. The spatiotemporal expression pattern of the reporter gene confirmed that the 2.9 kb MUC2 promoter could retain the regulatory element to drive expression of target genes in intestinal tissues after hatching. This new transgene expression system, using the MUC2 promoter, will provide a new method of overexpressing target genes to study gene function in the avian intestine.

  6. Identification of the MUC2 Promoter as a Strong Promoter for Intestinal Gene Expression through Generation of Transgenic Quail Expressing GFP in Gut Epithelial Cells

    Science.gov (United States)

    Woodfint, Rachel M.; Chen, Paula R.; Ahn, Jinsoo; Suh, Yeunsu; Hwang, Seongsoo; Lee, Sang Suk; Lee, Kichoon

    2017-01-01

    Identification of tissue- and stage-specific gene promoters is valuable for delineating the functional roles of specific genes in genetically engineered animals. Here, through the comparison of gene expression in different tissues by analysis of a microarray database, the intestinal specificity of mucin 2 (MUC2) expression was identified in mice and humans, and further confirmed in chickens by RT-PCR (reverse transcription-PCR) analysis. An analysis of cis-acting elements in avian MUC2 gene promoters revealed conservation of binding sites, within a 2.9 kb proximal promoter region, for transcription factors such as caudal type homeobox 2 (CDX2), GATA binding protein 4 (GATA4), hepatocyte nuclear factor 4 α (HNF4A), and transcription factor 4 (TCF4) that are important for maintaining intestinal homeostasis and functional integrity. By generating transgenic quail, we demonstrated that the 2.9 kb chicken MUC2 promoter could drive green fluorescent protein (GFP) reporter expression exclusively in the small intestine, large intestine, and ceca. Fluorescence image analysis further revealed GFP expression in intestine epithelial cells. The GFP expression was barely detectable in the embryonic intestine, but increased during post-hatch development. The spatiotemporal expression pattern of the reporter gene confirmed that the 2.9 kb MUC2 promoter could retain the regulatory element to drive expression of target genes in intestinal tissues after hatching. This new transgene expression system, using the MUC2 promoter, will provide a new method of overexpressing target genes to study gene function in the avian intestine. PMID:28106824

  7. Development of an agroinoculation system for full-length and GFP-tagged cDNA clones of cucumber green mottle mosaic virus.

    Science.gov (United States)

    Zheng, Hongying; Xiao, Caili; Han, Kelei; Peng, Jiejun; Lin, Lin; Lu, Yuwen; Xie, Li; Wu, Xiaohua; Xu, Pei; Li, Guojing; Chen, Jianping; Yan, Fei

    2015-11-01

    The complete 6243-nucleotide sequence of a cucumber green mottle mosaic virus (CGMMV) isolate from bottle gourd in Zhejiang province, China, was determined. A full-length cDNA clone of this isolate was constructed by inserting the cDNA between the 35S promoter and the ribozyme in the binary plasmid pCB301-CH. A suspension of an Agrobacterium tumefaciens EHA105 clone carrying this construct was highly infectious in Nicotiana benthamiana and bottle gourd. Another infectious clone containing the green fluorescence protein (GFP) reporter gene was also successfully constructed. This study is the first report of the efficient use of agroinoculation for generating CGMMV infections.

  8. Monitoring the diffusion behavior of Na,K-ATPase by fluorescence correlation spectroscopy (FCS) upon fluorescence labelling with eGFP or Dreiklang

    Science.gov (United States)

    Junghans, Cornelia; Schmitt, Franz-Josef; Vukojević, Vladana; Friedrich, Thomas

    2016-02-01

    Measurement of lateral mobility of membraneembedded proteins in living cells with high spatial and temporal precision is a challenging task of optofluidics. Biological membranes are complex structures, whose physico-chemical properties depend on the local lipid composition, cholesterol content and the presence of integral or peripheral membrane proteins, which may be involved in supramolecular complexes or are linked to cellular matrix proteins or the cytoskeleton. The high proteinto- lipid ratios in biomembranes indicate that membrane proteins are particularly subject to molecular crowding, making it difficult to follow the track of individual molecules carrying a fluorescence label. Novel switchable fluorescence proteins such as Dreiklang [1], are, in principle, promising tools to study the diffusion behavior of individual molecules in situations of molecular crowding due to excellent spectral control of the ON- and OFF-switching process. In this work, we expressed an integral membrane transport protein, the Na,K-ATPase comprising the human α2-subunit carrying an N-terminal eGFP or Dreiklang tag and human β1-subunit, in HEK293T cells and measured autocorrelation curves by fluorescence correlation spectroscopy (FCS). Furthermore,we measured diffusion times and diffusion constants of eGFP and Dreiklang by FCS, first, in aqueous solution after purification of the proteins upon expression in E. coli, and, second, upon expression as soluble proteins in the cytoplasm of HEK293T cells. Our data show that the diffusion behavior of the purified eGFP and Dreiklang in solution as well as the properties of the proteins expressed in the cytoplasm are very similar. However, the autocorrelation curves of eGFP- and Dreiklanglabeled Na,K-ATPase measured in the plasma membrane exhibit marked differences, with the Dreiklang-labeled construct showing shorter diffusion times. This may be related to an additional, as yet unrecognized quenching process that occurs on the same time

  9. Isolation, Culture, and Immunostaining of Skeletal Muscle Myofibers from Wildtype and Nestin-GFP Mice as a Means to Analyze Satellite Cell.

    Science.gov (United States)

    Stuelsatz, Pascal; Keire, Paul; Yablonka-Reuveni, Zipora

    2017-01-01

    Multinucleated myofibers, the functional contractile units of adult skeletal muscle, harbor mononuclear Pax7(+) myogenic progenitors on their surface between the myofiber basal lamina and plasmalemma. These progenitors, known as satellite cells, are the primary myogenic stem cells in adult muscle. This chapter describes our laboratory protocols for isolating, culturing, and immunostaining intact myofibers from mouse skeletal muscle as a means for studying satellite cell dynamics. The first protocol discusses myofiber isolation from the flexor digitorum brevis (FDB) muscle. These short myofibers are plated in dishes coated with PureCol collagen (formerly known as Vitrogen) and maintained in a mitogen-poor medium (± supplemental growth factors). Employing such conditions, satellite cells remain at the surface of the parent myofiber while synchronously undergoing a limited number of proliferative cycles and rapidly differentiate. The second protocol discusses the isolation of longer myofibers from the extensor digitorum longus (EDL) muscle. These EDL myofibers are routinely plated individually as adherent myofibers in wells coated with Matrigel and maintained in a mitogen-rich medium, conditions in which satellite cells migrate away from the parent myofiber, proliferate extensively, and generate numerous differentiating progeny. Alternatively, these EDL myofibers can be plated as non-adherent myofibers in uncoated wells and maintained in a mitogen-poor medium (± supplemental growth factors), conditions that retain satellite cell progeny at the myofiber niche similar to the FDB myofiber cultures. However, the adherent myofiber format is our preferred choice for monitoring satellite cells in freshly isolated (Time 0) myofibers. We conclude this chapter by promoting the Nestin-GFP transgenic mouse as an efficient tool for direct analysis of satellite cells in isolated myofibers. While satellite cells have been often detected by their expression of the Pax7 protein or

  10. Antigen Uptake during Different Life Stages of Zebrafish (Danio rerio) Using a GFP-Tagged Yersinia ruckeri

    DEFF Research Database (Denmark)

    Korbut, Rozalia; Mehrdana, Foojan; Kania, Per Walter;

    2016-01-01

    and subsequent antigen transport in fish. A genetically modified Yr was developed to constitutively express green fluorescent protein (GFP) and was used for bacterin production. Larval, juvenile and adult transparent zebrafish (tra:nac mutant) received a bath in the bacterin for up to 30 minutes. Samples were......Immersion-vaccines (bacterins) are routinely used for aquacultured rainbow trout to protect against Yersinia ruckeri (Yr). During immersion vaccination, rainbow trout take up and process the antigens, which induce protection. The zebrafish was used as a model organism to study uptake mechanisms...

  11. 腺病毒穿梭质粒pShuttle CMV-BMP2+-IRES-hrGFP-1的构建和鉴定%Construction and Identification of Recombinant Adenovirus Shuttle Plasimid pShuttle CMV-BMP2 +-IRES-GFP-1

    Institute of Scientific and Technical Information of China (English)

    张正; 刘丹平; 蒲勤; 郭韬; 张男

    2005-01-01

    目的构建腺病毒穿梭质粒pShuttle CMV-BMP2+-IRES-hrGFP-1,为构建表达具有抗原表位标记的骨形态发生蛋白2(bone morpbogenetic protein 2,BMP-2),并同时表达绿色荧光蛋白(green fluorescent protein,GFP)报告分子的腺病毒真核细胞表达载体打下基础.方法对目的基因供体质粒pcDNA3-BMP2携带的BMP2基因测序和序列内部存在的限制性内切酶识别位点进行分析,利用PCR(polymeras chain reaction,PCR)技术对pcDNA3-BMP2携带的BMP2基因突变,以去除翻译终止密码子后的基因序列并添加新的酶切识别位点Xho Ⅰ.测序检测突变情况,将突变后的BMP2基因(BMP2+基因)定向连入腺病毒穿梭质粒pShuttleCMV-IRES-hrGFP-1,通过限制性内切酶酶切图谱分析鉴定获得的重组质粒.结果重组质粒经双酶切鉴定图谱正确.结论成功构建了pShuttle CMV-BMP2+-IRES-hrGFP-1.

  12. 稳定表达PAcGFP1-Golgi质粒的中国仓鼠卵巢细胞株的构建%Construction of China Hamster Ovary Cell Line with Stable Expression of PAcGFP1-Golgi

    Institute of Scientific and Technical Information of China (English)

    刘城霞; 凌云; 舒瑛; 王纯; 雷清华; 余从年

    2009-01-01

    目的:将质粒PAcGFP1-Golgi转染到中国仓鼠卵巢细胞(CHO细胞)并进行筛选纯化,得到单一克隆细胞株,从而构建能很好显示高尔基体形态、分布和功能的新模型.方法:将质粒PAcGFP1-Golgi以脂质体法转染CHO细胞,稳定后用G418筛选、平板稀释法克隆细胞;克隆完成后以激光共聚焦显微镜观察高尔基体形态及分布,动态监测荧光表达率,MTT法检测细胞增殖活性.结果:成功获得稳定表达质粒PAcGFP1-Golgi的CHO细胞株,激光共聚焦显微镜下高尔基体显示清晰,荧光表达率高达(99.31±0.26)%且表达稳定,细胞增殖活性与空白CHO细胞无异.结论:稳定表达PAcGFP1-Golgi质粒的CHO细胞株构建成功,为进一步研究高尔基体、COG复合体及其与遗传性糖基化障碍疾病之间的关系打下基础.

  13. Intravital FRAP Imaging using an E-cadherin-GFP Mouse Reveals Disease- and Drug-Dependent Dynamic Regulation of Cell-Cell Junctions in Live Tissue

    Directory of Open Access Journals (Sweden)

    Zahra Erami

    2016-01-01

    Full Text Available E-cadherin-mediated cell-cell junctions play a prominent role in maintaining the epithelial architecture. The disruption or deregulation of these adhesions in cancer can lead to the collapse of tumor epithelia that precedes invasion and subsequent metastasis. Here we generated an E-cadherin-GFP mouse that enables intravital photobleaching and quantification of E-cadherin mobility in live tissue without affecting normal biology. We demonstrate the broad applications of this mouse by examining E-cadherin regulation in multiple tissues, including mammary, brain, liver, and kidney tissue, while specifically monitoring E-cadherin mobility during disease progression in the pancreas. We assess E-cadherin stability in native pancreatic tissue upon genetic manipulation involving Kras and p53 or in response to anti-invasive drug treatment and gain insights into the dynamic remodeling of E-cadherin during in situ cancer progression. FRAP in the E-cadherin-GFP mouse, therefore, promises to be a valuable tool to fundamentally expand our understanding of E-cadherin-mediated events in native microenvironments.

  14. Green fluorescent protein (GFP)-based overexpression screening and characterization of AgrC, a Receptor protein of quorum sensing in Staphylococcus aureus.

    Science.gov (United States)

    Wang, Lina; Quan, Chunshan; Liu, Baoquan; Xu, Yongbin; Zhao, Pengchao; Xiong, Wen; Fan, Shengdi

    2013-09-06

    Staphylococcus aureus AgrC is an important component of the agr quorum-sensing system. AgrC is a membrane-embedded histidine kinase that is thought to act as a sensor for the recognition of environmental signals and the transduction of signals into the cytoplasm. However, the difficulty of expressing and purifying functional membrane proteins has drastically hindered in-depth understanding of the molecular structures and physiological functions of these proteins. Here, we describe the high-yield expression and purification of AgrC, and analyze its kinase activity. A C-terminal green fluorescent protein (GFP) fusion to AgrC served as a reporter for monitoring protein expression levels in real time. Protein expression levels were analyzed by the microscopic assessment of the whole-cell fluorescence. The expressed AgrC-GFP protein with a C-terminal His-tagged was purified using immobilized metal affinity chromatography (IMAC) and size exclusion chromatography (SEC) at yields of ≥ 10 mg/L, following optimization. We also assessed the effects of different detergents on membrane solubilization and AgrC kinase activity, and polyoxyethylene-(23)-lauryl-ether (Brij-35) was identified as the most suitable detergent. Furthermore, the secondary structural stability of purified AgrC was analyzed using circular dichroism (CD) spectroscopy. This study may serve as a general guide for improving the yields of other membrane protein preparations and selecting the appropriate detergent to stabilize membrane proteins for biophysical and biochemical analyses.

  15. Intravital FRAP Imaging using an E-cadherin-GFP Mouse Reveals Disease- and Drug-Dependent Dynamic Regulation of Cell-Cell Junctions in Live Tissue

    Science.gov (United States)

    Erami, Zahra; Herrmann, David; Warren, Sean C.; Nobis, Max; McGhee, Ewan J.; Lucas, Morghan C.; Leung, Wilfred; Reischmann, Nadine; Mrowinska, Agata; Schwarz, Juliane P.; Kadir, Shereen; Conway, James R.W.; Vennin, Claire; Karim, Saadia A.; Campbell, Andrew D.; Gallego-Ortega, David; Magenau, Astrid; Murphy, Kendelle J.; Ridgway, Rachel A.; Law, Andrew M.; Walters, Stacey N.; Grey, Shane T.; Croucher, David R.; Zhang, Lei; Herzog, Herbert; Hardeman, Edna C.; Gunning, Peter W.; Ormandy, Christopher J.; Evans, T.R. Jeffry; Strathdee, Douglas; Sansom, Owen J.; Morton, Jennifer P.; Anderson, Kurt I.; Timpson, Paul

    2015-01-01

    Summary E-cadherin-mediated cell-cell junctions play a prominent role in maintaining the epithelial architecture. The disruption or deregulation of these adhesions in cancer can lead to the collapse of tumor epithelia that precedes invasion and subsequent metastasis. Here we generated an E-cadherin-GFP mouse that enables intravital photobleaching and quantification of E-cadherin mobility in live tissue without affecting normal biology. We demonstrate the broad applications of this mouse by examining E-cadherin regulation in multiple tissues, including mammary, brain, liver, and kidney tissue, while specifically monitoring E-cadherin mobility during disease progression in the pancreas. We assess E-cadherin stability in native pancreatic tissue upon genetic manipulation involving Kras and p53 or in response to anti-invasive drug treatment and gain insights into the dynamic remodeling of E-cadherin during in situ cancer progression. FRAP in the E-cadherin-GFP mouse, therefore, promises to be a valuable tool to fundamentally expand our understanding of E-cadherin-mediated events in native microenvironments. PMID:26725115

  16. Fine processes of Nestin-GFP-positive radial glia-like stem cells in the adult dentate gyrus ensheathe local synapses and vasculature.

    Science.gov (United States)

    Moss, Jonathan; Gebara, Elias; Bushong, Eric A; Sánchez-Pascual, Irene; O'Laoi, Ruadhan; El M'Ghari, Imane; Kocher-Braissant, Jacqueline; Ellisman, Mark H; Toni, Nicolas

    2016-05-03

    Adult hippocampal neurogenesis relies on the activation of neural stem cells in the dentate gyrus, their division, and differentiation of their progeny into mature granule neurons. The complex morphology of radial glia-like (RGL) stem cells suggests that these cells establish numerous contacts with the cellular components of the neurogenic niche that may play a crucial role in the regulation of RGL stem cell activity. However, the morphology of RGL stem cells remains poorly described. Here, we used light microscopy and electron microscopy to examine Nestin-GFP transgenic mice and provide a detailed ultrastructural reconstruction analysis of Nestin-GFP-positive RGL cells of the dentate gyrus. We show that their primary processes follow a tortuous path from the subgranular zone through the granule cell layer and ensheathe local synapses and vasculature in the inner molecular layer. They share the ensheathing of synapses and vasculature with astrocytic processes and adhere to the adjacent processes of astrocytes. This extensive interaction of processes with their local environment could allow them to be uniquely receptive to signals from local neurons, glia, and vasculature, which may regulate their fate.

  17. Locally-excited (LE) versus charge-transfer (CT) excited state competition in a series of para-substituted neutral green fluorescent protein (GFP) chromophore models.

    Science.gov (United States)

    Olsen, Seth

    2015-02-12

    In this paper, I provide a characterization of the low-energy electronic structure of a series of para-substituted neutral green fluorescent protein (GFP) chromophore models using a theoretical approach that blends linear free energy relationships (LFERs) with state-averaged complete-active-space self-consistent field (SA-CASSCF) theory. The substituents are chosen to sample the Hammett σ(p) scale from R = F to NH2, and a model of the neutral GFP chromophore structure (R = OH) is included. I analyze the electronic structure for different members of the series in a common complete-active-space valence-bond (CASVB) representation, exploiting an isolobal analogy between active-space orbitals for different members of the series. I find that the electronic structure of the lowest adiabatic excited state is a strong mixture of weakly coupled states with charge-transfer (CT) or locally excited (LE) character and that the dominant character changes as the series is traversed. Chromophores with strongly electron-donating substituents have a CT-like excited state such as expected for a push-pull polyene or asymmetric cyanine. Chromophores with weakly electron-donating (or electron-withdrawing) substituents have an LE-like excited state with an ionic biradicaloid structure localized to the ground-state bridge π bond.

  18. Green Fluorescent Protein (GFP-Based Overexpression Screening and Characterization of AgrC, a Receptor Protein of Quorum Sensing in Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Shengdi Fan

    2013-09-01

    Full Text Available Staphylococcus aureus AgrC is an important component of the agr quorum-sensing system. AgrC is a membrane-embedded histidine kinase that is thought to act as a sensor for the recognition of environmental signals and the transduction of signals into the cytoplasm. However, the difficulty of expressing and purifying functional membrane proteins has drastically hindered in-depth understanding of the molecular structures and physiological functions of these proteins. Here, we describe the high-yield expression and purification of AgrC, and analyze its kinase activity. A C-terminal green fluorescent protein (GFP fusion to AgrC served as a reporter for monitoring protein expression levels in real time. Protein expression levels were analyzed by the microscopic assessment of the whole-cell fluorescence. The expressed AgrC-GFP protein with a C-terminal His-tagged was purified using immobilized metal affinity chromatography (IMAC and size exclusion chromatography (SEC at yields of ≥10 mg/L, following optimization. We also assessed the effects of different detergents on membrane solubilization and AgrC kinase activity, and polyoxyethylene-(23-lauryl-ether (Brij-35 was identified as the most suitable detergent. Furthermore, the secondary structural stability of purified AgrC was analyzed using circular dichroism (CD spectroscopy. This study may serve as a general guide for improving the yields of other membrane protein preparations and selecting the appropriate detergent to stabilize membrane proteins for biophysical and biochemical analyses.

  19. Detection of a Putative TetR-Like Gene Related to Mycobacterium bovis BCG Growth in Cholesterol Using a gfp-Transposon Mutagenesis System

    Science.gov (United States)

    Otal, Isabel; Pérez-Herrán, Esther; Garcia-Morales, Lazaro; Menéndez, María C.; Gonzalez-y-Merchand, Jorge A.; Martín, Carlos; García, María J.

    2017-01-01

    In vitro transposition is a powerful genetic tool for identifying mycobacterial virulence genes and studying virulence factors in relation to the host. Transposon shuttle mutagenesis is a method for constructing stable insertions in the genome of different microorganisms including mycobacteria. Using an IS1096 derivative, we have constructed the Tngfp, a transposon containing a promoterless green fluorescent protein (gfp) gene. This transposon was able to transpose randomly in Mycobacterium bovis BCG. Bacteria with a single copy of the gfp gene per chromosome from an M. bovis BCG::Tngfp library were analyzed and cells exhibiting high levels of fluorescence were detected by flow cytometry. Application of this approach allowed for the selection of a mutant, BCG_2177c::Tngfp (BCG-Tn), on the basis of high level of long-standing fluorescence at stationary phase. This BCG-Tn mutant showed some particular phenotypic features compared to the wild type strain, mainly during stationary phase, when cholesterol was used as a sole carbon source, thus supporting the relationships of the targeted gene with the regulation of cholesterol metabolism in this bacteria. This approach showed that Tngfp is a potentially useful tool for studying the involvement of the targeted loci in metabolic pathways of mycobacteria. PMID:28321208

  20. Rescue of recombinant peste des petits ruminants virus: creation of a GFP-expressing virus and application in rapid virus neutralization test

    Directory of Open Access Journals (Sweden)

    Hu Qianqian

    2012-06-01

    Full Text Available Abstract Peste des petits ruminants virus (PPRV causes high mortality in goats and sheep and the disease has shown a greatly increased geographic distribution over the last 15 years. It is responsible for serious socioeconomic problems in some of the poorest developing countries. The ability to create recombinant PPRV would provide a useful tool for investigating the biology of the virus and the pathology of disease, as well as for developing new vaccines and diagnostic methods. Here we report the first successful rescue of recombinant PPRV from a full-length cDNA clone of the virus genome. Successful recovery of PPRV was achieved by using a RNA polymerase II promoter to drive transcription of the full-length virus antigenome. We have used this technique to construct a virus expressing a tracer protein (green fluorescent protein, GFP. The recombinant virus replicated as well as the parental virus and could stably express GFP during at least 10 passages. The newly established reverse genetics system for PPRV provides a novel method for constructing a vaccine using PPRV as a vector, and will also prove valuable for fundamental research on the biology of the virus. We found that our recombinant virus allowed more rapid and higher throughput assessment of PPRV neutralization antibody titer via the virus neutralization test (VNT compared with the traditional method.

  1. Mucosal healing and fibrosis after acute or chronic inflammation in wild type FVB-N mice and C57BL6 procollagen α1(I-promoter-GFP reporter mice.

    Directory of Open Access Journals (Sweden)

    Shengli Ding

    Full Text Available BACKGROUND: Injury and intestinal inflammation trigger wound healing responses that can restore mucosal architecture but if chronic, can promote intestinal fibrosis. Intestinal fibrosis is a major complication of Crohn's disease. The cellular and molecular basis of mucosal healing and intestinal fibrosis are not well defined and better understanding requires well characterized mouse models. METHODS: FVB-N wild type mice and C57BL6 procollagen α1(I-GFP reporter mice were given one (DSS1 or two (DSS2 cycles of 3% DSS (5 days/cycle followed by 7 days recovery. Histological scoring of inflammation and fibrosis were performed at DSS1, DSS1+3, DSS1+7, DSS2, DSS2+3, and DSS2+7. Procollagen α1(I-GFP activation was assessed in DSS and also TNBS models by whole colon GFP imaging and fluorescence microscopy. Colocalization of GFP with α-smooth muscle actin (α-SMA or vimentin was examined. GFP mRNA levels were tested for correlation with endogenous collagen α1(I mRNA. RESULTS: Males were more susceptible to DSS-induced disease and mortality than females. In FVB-N mice one DSS cycle induced transient mucosal inflammation and fibrosis that resolved by 7 days of recovery. Two DSS cycles induced transmural inflammation and fibrosis in a subset of FVB-N mice but overall, did not yield more consistent, severe or sustained fibrosis. In C57BL6 mice, procollagen α1(I-GFP reporter was activated at the end of DSS1 and through DSS+7 with more dramatic and transmural activation at DSS2 through DSS2+7, and in TNBS treated mice. In DSS and TNBS models GFP reporter expression localized to vimentin(+ cells and much fewer α-SMA(+ cells. GFP mRNA strongly correlated with collagen α1(I mRNA. CONCLUSIONS: One DSS cycle in FVB-N mice provides a model to study mucosal injury and subsequent mucosal healing. The procollagen α1(I-GFP transgenic provides a useful model to study activation of a gene encoding a major extracellular matrix protein during acute or chronic

  2. Dynamics of GFP-Fusion p110α and p110β Isoforms of PI3K Signaling Pathway in Normal and Cancer Cells.

    Science.gov (United States)

    Singh, Paramjeet; Dar, Mohd Saleem; Singh, Gurjinder; Jamwal, Gayatri; Sharma, Parduman Raj; Ahmad, Muzamil; Dar, Mohd Jamal

    2016-12-01

    Cancer therapeutics is a hot subject and PI3K class 1A isoforms (p110α and p110β) are pursued as major targets. Genetic analysis, biochemical approaches, and structural studies have demonstrated crucial roles for these isoforms in several physiological processes. p110α is critical for insulin signaling, whereas p110β is essential for the growth and differs from p110α in many ways. Here, we have generated GFP-fusion clones of wildtype and mutant version of p110α and p110β and expressed them in HEK293 and cancer cells to examine their subcellular localization and their impact on downstream signaling. In HEK293 cells, p110β GFP-fusion protein is translocated into the nucleus, whereas p110α-GFP stays exclusively in the cytoplasm. This study demonstrates that p110α and p110β oncogenecity, kinase activity, and interaction with p85 regulatory subunit does not have any impact on their subcellular localization. PI3K pathway specific inhibitor, LY294002, abrogated PI3K signaling by reducing pAkt levels, however, the subcellular localization of p110α and p110β remained unchanged. Furthermore, we analyzed the expression of recombinant p110α and p110β in a panel of human cancer cells and observed remarkable differences in their expression levels. The differential expression of recombinant p110α and p110β was observed to be mainly regulated by the endogenous levels of pAkt. Unlike in HEK293, p110α showed nuclear localization in cancer cells in a similar fashion to p110β. Moreover, we observed the PI3K signaling activities in low pAkt expressing cells are mediated by PDK1 and S6K proteins. Finally, p110α and p110β were seen to play an essential role in promoting the cell cycle progression in MCF-7 and HCT-116 cells. J. Cell. Biochem. 117: 2864-2874, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  3. Processus ultra-rapides associés à la dynamique d'émission de la protéine GFP

    Science.gov (United States)

    Didier, P.; Guidoni, L.; Schwalbach, G.; Bigot, J.-Y.

    2002-06-01

    La protéine GFP (Green Fluorescent Protein) est un marqueur très efficace, utilisable en milieu vivant. La spectroscopie femtoseconde est particulièrement bien adaptée pour comprendre les mécanismes d'émission de cette protéine, étant donné la rapidité des processus de transfert mis en jeu. Nous-présentons des résultats sur la dynamique spectro-temporelle d'émission du mutant GFPuv résolue à l'échelle de la centaine de femtosecondes. Une transition Raman à 3300 cm^{-1} ainsi que la dynamique d'etablissement du gain avec un temps caractéristique d'environ 1.5 ps ont été mis en évidence.

  4. Study of action of cyclophosphamide and extract of mycelium of Pleurotus ostreatus in vivo on mice, bearing melanoma B16-F0-GFP

    Science.gov (United States)

    Meerovich, Irina G.; Yang, Meng; Jiang, Ping; Hoffman, Robert M.; Gerasimenya, Valery P.; Orlov, Alexander E.; Savitsky, Alexander P.; Popov, Vladimir O.

    2005-04-01

    In this work we studied in vivo the combined action of cyclophosphamide and the extract of mycelium of Pleurotus ostreatus on mice bearing melanoma B16-F0, expressing green fluorescent protein (GFP). This model allows to recognize small-size tumors and metastases, unrecognizable by other methods. It was found that combined administration of cyclophosphamide (300 mg/kg) and the extract of mycelium of Pleurotus ostreatus (100 mg/kg), administered for 10 days after cyclophosphamide injection, as well administration of cyclophosphamide alone, cause inhibition of tumor growth about 97%. It was shown that administration of the extract of mycelium of Pleurotus ostreatus alone leads to inhibition of tumor growth of 61%. It was found that in case of combined administration of cyclophosphamide and the extract of mycelium of Pleurotus ostreatus, leucopenia was less expressed than in case of administration of cyclophosphamide alone.

  5. Identification of Putative ORF5 Protein of Porcine Circovirus Type 2 and Functional Analysis of GFP-Fused ORF5 Protein.

    Directory of Open Access Journals (Sweden)

    Qizhuang Lv

    Full Text Available Porcine circovirus type 2 (PCV2 is the essential infectious agent responsible for causing porcine circovirus-associated diseases in pigs. To date, eleven RNAs and five viral proteins of PCV2 have been detected. Here, we identified a novel viral gene within the PCV2 genome, termed ORF5, that exists at both the transcriptional and translational level during productive infection of PCV2 in porcine alveolar macrophages 3D4/2 (PAMs. Northern blot analysis was used to demonstrate that the ORF5 gene measures 180 bp in length and overlaps completely with ORF1 when read in the same direction. Site-directed mutagenesis was used to show that the ORF5 protein is not essential for PCV2 replication. To investigate the biological functions of the novel protein, we constructed a recombinant eukaryotic expression plasmid capable of expressing PCV2 ORF5. The results show that the GFP-tagged PCV2 ORF5 protein localizes to the endoplasmic reticulum (ER, is degraded via the proteasome, inhibits PAM growth and prolongs the S-phase of the cell cycle. Further studies show that the GFP-tagged PCV2 ORF5 protein induces ER stress and activates NF-κB, which was further confirmed by a significant upregulation in IL-6, IL-8 and COX-2 expression. In addition, five cellular proteins (GPNMB, CYP1A1, YWHAB, ZNF511 and SRSF3 were found to interact with ORF5 via yeast two-hybrid assay. These findings provide novel information on the identification and functional analysis of the PCV2 ORF5 protein and are likely to be of benefit in elucidating the molecular mechanisms of PCV2 pathogenicity. However, additional experiments are needed to validate the expression and function of the ORF5 protein during PCV2 infection in vitro before any definitive conclusion can be drawn.

  6. In vivo functional calcium imaging of induced or spontaneous activity in the fly brain using a GFP-apoaequorin-based bioluminescent approach.

    Science.gov (United States)

    Minocci, Daiana; Carbognin, Elena; Murmu, Meena Sriti; Martin, Jean-René

    2013-07-01

    Different optical imaging techniques have been developed to study neuronal activity with the goal of deciphering the neural code underlying neurophysiological functions. Because of several constraints inherent in these techniques as well as difficulties interpreting the results, the majority of these studies have been dedicated more to sensory modalities than to the spontaneous activity of the central brain. Recently, a novel bioluminescence approach based on GFP-aequorin (GA) (GFP: Green fluorescent Protein), has been developed, allowing us to functionally record in-vivo neuronal activity. Taking advantage of the particular characteristics of GA, which does not require light excitation, we report that we can record induced and/or the spontaneous Ca(2+)-activity continuously over long periods. Targeting GA to the mushrooms-bodies (MBs), a structure implicated in learning/memory and sleep, we have shown that GA is sensitive enough to detect odor-induced Ca(2+)-activity in Kenyon cells (KCs). It has been possible to reveal two particular peaks of spontaneous activity during overnight recording in the MBs. Other peaks of spontaneous activity have been recorded in flies expressing GA pan-neurally. Similarly, expression in the glial cells has revealed that these cells exhibit a cell-autonomous Ca(2+)-activity. These results demonstrate that bioluminescence imaging is a useful tool for studying Ca(2+)-activity in neuronal and/or glial cells and for functional mapping of the neurophysiological processes in the fly brain. These findings provide a framework for investigating the biological meaning of spontaneous neuronal activity. This article is part of a Special Issue entitled: 12th European Symposium on Calcium.

  7. Using multi-channel level sets to measure the cytoplasmic localization of HCMV pUL97 in GFP-B-gal fusion constructs.

    Science.gov (United States)

    Held, Christian; Webel, Rike; Palmisano, Ralf; Hutterer, Corina; Marschall, Manfred; Wittenberg, Thomas

    2014-04-01

    Human cytomegalovirus UL97-encoded protein kinase (pUL97) phosphorylates cellular and viral proteins and is critical for viral replication. To quantify the efficiency of nuclear translocation and to elucidate the role of putative nuclear localization signal (NLS) elements, immunofluorescence analysis of different pUL97 expression constructs was performed. Since manual quantitation of respective expression levels lacks objectivity and reproducibility, and is time-consuming as well, a computer-based model is established. This model enables objective quantitation of the degree of cytoplasmic localization λ. To determine the degree of cytoplasmic localization of different pUL97-GFP-β-gal fusion proteins automatically, a multi-channel segmentation of the nucleus and cytoplasm of transfected HeLa cells is performed in DAPI and GFP micrographs. A watershed transform-based segmentation scheme is used for the segmentation of the cell nuclei. Subsequently, the cytoplasm is segmented using a fast marching level set method. Based on the segmentation of cell nuclei and cytoplasm, λ can be determined for each HeLa cell by quantitation of the ratio of average signal intensity outside and inside the nucleus. The degree of cytoplasmic localization of an individual construct is then determined by evaluating the average and standard deviation of λ for the corresponding HeLa cells. Evaluation demonstrates that nuclear transport of pUL97 is a multilayered mechanism resulting in different efficiencies of nuclear translocation between a small and a large isoform and objective quantitation of the cytoplasmic localization is possible with a high accuracy (96.7% and 94.3%). Copyright © 2013 Elsevier B.V. All rights reserved.

  8. Identification of the avian RBP7 gene as a new adipose-specific gene and RBP7 promoter-driven GFP expression in adipose tissue of transgenic quail.

    Science.gov (United States)

    Ahn, Jinsoo; Shin, Sangsu; Suh, Yeunsu; Park, Ju Yeon; Hwang, Seongsoo; Lee, Kichoon

    2015-01-01

    The discovery of an increasing number of new adipose-specific genes has significantly contributed to our understanding of adipose tissue biology and the etiology of obesity and its related diseases. In the present study, comparison of gene expression profiles among various tissues was performed by analysis of chicken microarray data, leading to identification of RBP7 as a novel adipose-specific gene in chicken. Adipose-specific expression of RBP7 in the avian species was further confirmed at the protein and mRNA levels. Examination of the transcription factor binding sites within the chicken RBP7 promoter by Matinspector software revealed potential binding sites for adipogenic transcription factors. This led to the hypothesis that the RBP7 promoter can be utilized to overexpress a transgene in adipose tissue in order to further investigate the function of a transgene in adipose tissue. Several lines of transgenic quail containing a green fluorescent protein (GFP) gene under the control of the RBP7 promoter were generated using lentivirus-mediated gene transfer. The GFP expression in transgenic quail was specific to adipose tissue and increased after adipocyte differentiation. This expression pattern was consistent with endogenous RBP7 expression, suggesting the RBP7 promoter is sufficient to overexpress a gene of interest in adipose tissue at later developmental stages. These findings will lead to the establishment of a novel RBP7 promoter cassette which can be utilized for overexpressing genes of interest in adipose tissue in vivo to study the function of genes in adipose tissue development and lipid metabolism.

  9. Gateway技术构建转基因重组质粒pRP.EX3d-EF1A-LRP16-His-IRES-eGFP%Application of gateway technology in construction of recombinant transgenic vector pRP. EX3d-EF1A-LRP16-His-IRES-eGFP

    Institute of Scientific and Technical Information of China (English)

    柏苗苗; 王春萌; 伍志强; 梅倩; 李小雷; 李祥; 赵亚力; 韩为东

    2014-01-01

    Objective To lay the foundation for establishing transgenic mice by constructing recombinant transgenic vector pRP. EX3d-EF1A-LRP16-His-IRES-eGFP. Methods The attB1- LRP16-His-attB2 was amplified by overlap PCR. The LRP16 gene was cloned into pDown vector via BP reaction and transmitted into pRP.EX3d vector via LR reaction with pDown-LRP16-His, pUp-EF1A, pTail-IRES-eGFP and PRP. Des3d. The recombinant plasmid was transformed into Stbl3 cells and screened using the ampicillin (AMP) resistance gene. Positive clones were confirmed by PCR and DNA sequencing, respectively. Results Sequencing and restriction endonuclease showed that the recombinant vector pRP.EX3d-EF1A-LRP16-His-IRES-eGFP was successfully constructed. Conclusion The successfully constructed recombinant vector pRP.EX3d-EF1A-LRP16-His-IRES-eGFP can be used in establishing LRP16 transgenic mice.%目的:构建转基因重组质粒pRP.EX3d-EF1A-LRP16-His-IRES-eGFP,为转基因鼠的建立奠定基础。方法利用重叠PCR技术扩增attB1-LRP16-His-attB2,经BP反应,将LRP16基因插入到载体pDown上,pUp-EF1A、pDown-LRP16-His、pTail-IRES-eGFP和PRP.Des3d经LR反应,将LRP16转移到pRP.EX3d上,转化Stbl3细胞,用氨苄西林进行抗性筛选,经PCR鉴定后将阳性克隆送测序。结果测序及酶切结果验证获得正确的pRP.EX3d-EF1A-LRP16-His-IRES-eGFP重组质粒。结论成功构建pRP.EX3d-EF1A-LRP16-His-IRES-eGFP重组质粒,可用于下一步LRP16转基因小鼠的构建。

  10. Establishment and dynamic in vivo imaging of a radioresistant,GFP-labelled xenograft tumor model of human nasopharyngeal carcinoma in mouse%绿色荧光蛋白标记的鼻咽癌放射抗拒性裸鼠移植瘤模型的建立及其活体成像观察

    Institute of Scientific and Technical Information of China (English)

    黄小鹏; 马慧; 朱小东; 葛莲英; 曲颂; 李龄; 郭亚; 赵伟; 黎丹戎

    2013-01-01

    Objective To establish a GFP-labelled radioresistant xenograft tumor model of human nasopharyngeal carcinoma(NPC) and build the foundation for further study. Methods Lentivirus was used to establish a stable,radioresistant human NPC cell line expressing GFP(GFP-CNE-2R)and a corresponding non-radioresistant cell line(GFP-CNE-2).Both lines were subcutaneously implanted into BALB/c-nu nude mice;when the tumors had reached 1 cm in size,the animals were irradiated with 10 Gy in 1 fraction.Tumor proliferation and metastasis were analyzed in vivo using dynamic imaging technology. Results GFP-CNE-2R and GFP-CNE-2 lines were successfully established,and clone formation assays showed GFP-CNE-2R cells to be radioresistant.Xenograft tumors were grown from GFP-CNE-2R and GFP-CNE-2 cells,and growth of GFP-CNE-2R tumors was not significantly inhibited by radiation. Conclusion GFP-CNE-2R xenograft tumors are more radioresistant than GFP-CNE-2 xenograft tumors.%目的:建立绿色荧光蛋白(green fluorescent protein,GFP)标记的鼻咽癌放射抗拒性裸鼠移植瘤模型,为后续研究奠定基础。方法将以慢病毒转染的方法建立稳定表达GFP标记的人鼻咽低分化鳞癌细胞株GFP-CNE-2和放射抗拒性细胞株GFP-CNE-2R接种至裸鼠体内,建立皮下移植的肿瘤模型。待肿瘤直径约为1 cm时给予相同剂量10 Gy的X射线一次性照射,通过小动物活体成像仪观察移植瘤的生长和转移情况。结果成功建立了稳定表达GFP标记的放射抗拒性及放射敏感的人鼻咽低分化鳞癌细胞株GFP-CNE-2R和GFP-CNE-2。克隆形成实验显示GFP-CNE-2R细胞株具有放射抗拒性。GFP-CNE-2R和GFP-CNE-2细胞的皮下成瘤率均为100%,证实建模成功。相对于GFP-CNE-2裸鼠移植瘤, GFP-CNE-2R移植瘤的生长受照射抑制不明显。结论相对于GFP-CNE-2裸鼠移植瘤,GFP-CNE-2R裸鼠移植瘤具有更强的放射抗拒性。

  11. A single amino acid change resulting in loss of fluorescence of eGFP in a viral fusion protein confers fitness and growth advantage to the recombinant vesicular stomatitis virus

    Energy Technology Data Exchange (ETDEWEB)

    Dinh, Phat X.; Panda, Debasis; Das, Phani B.; Das, Subash C.; Das, Anshuman [School of Veterinary Medicine and Biomedical Sciences, University of Nebraska-Lincoln, Lincoln, Nebraska 68583-0900 (United States); The Nebraska Center for Virology, University of Nebraska-Lincoln, Lincoln, Nebraska 68583-0900 (United States); Pattnaik, Asit K., E-mail: apattnaik2@unl.edu [School of Veterinary Medicine and Biomedical Sciences, University of Nebraska-Lincoln, Lincoln, Nebraska 68583-0900 (United States); The Nebraska Center for Virology, University of Nebraska-Lincoln, Lincoln, Nebraska 68583-0900 (United States)

    2012-10-25

    Using a recombinant vesicular stomatitis virus encoding eGFP fused in-frame with an essential viral replication protein, the phosphoprotein P, we show that during passage in culture, the virus mutates the nucleotide C289 within eGFP of the fusion protein PeGFP to A or T, resulting in R97S/C amino acid substitution and loss of fluorescence. The resultant non-fluorescent virus exhibits increased fitness and growth advantage over its fluorescent counterpart. The growth advantage of the non-fluorescent virus appears to be due to increased transcription and replication activities of the PeGFP protein carrying the R97S/C substitution. Further, our results show that the R97S/C mutation occurs prior to accumulation of mutations that can result in loss of expression of the gene inserted at the G-L gene junction. These results suggest that fitness gain is more important for the recombinant virus than elimination of expression of the heterologous gene.

  12. The effect of MEP pathway and other inhibitors on the intracellular localization of a plasma membrane-targeted, isoprenylable GFP reporter protein in tobacco BY-2 cells [v1; ref status: indexed, http://f1000r.es/yx

    Directory of Open Access Journals (Sweden)

    Michael Hartmann

    2013-08-01

    Full Text Available We have established an in vivo visualization system for the geranylgeranylation of proteins in a stably transformed tobacco BY-2 cell line, based on the expression of a dexamethasone-inducible GFP fused to the carboxy-terminal basic domain of the rice calmodulin CaM61, which naturally bears a CaaL geranylgeranylation motif (GFP-BD-CVIL. By using pathway-specific inhibitors it was demonstrated that inhibition of the methylerythritol phosphate (MEP pathway with known inhibitors like oxoclomazone and fosmidomycin, as well as inhibition of the protein geranylgeranyltransferase type 1 (PGGT-1, shifted the localization of the GFP-BD-CVIL protein from the membrane to the nucleus. In contrast, the inhibition of the mevalonate (MVA pathway with mevinolin did not affect the localization. During the present work, this test system has been used to examine the effect of newly designed inhibitors of the MEP pathway and inhibitors of sterol biosynthesis such as squalestatin, terbinafine and Ro48-8071. In addition, we also studied the impact of different post-prenylation inhibitors or those suspected to affect the transport of proteins to the plasma membrane on the localization of the geranylgeranylable fusion protein GFP-BD-CVIL.

  13. Use of sperm plasmid DNA lipofection combined with REMI (restriction enzyme-mediated insertion) for production of transgenic chickens expressing eGFP (enhanced green fluorescent protein) or human follicle-stimulating hormone.

    Science.gov (United States)

    Harel-Markowitz, Eliane; Gurevich, Michael; Shore, Laurence S; Katz, Adi; Stram, Yehuda; Shemesh, Mordechai

    2009-05-01

    Linearized p-eGFP (plasmid-enhanced green fluorescent protein) or p-hFSH (plasmid human FSH) sequences with the corresponding restriction enzyme were lipofected into sperm genomic DNA. Sperm transfected with p-eGFP were used for artificial insemination in hens, and in 17 out of 19 of the resultant chicks, the exogenous DNA was detected in their lymphocytes as determined by PCR and expressed in tissues as determined by (a) PCR, (b) specific emission of green fluorescence by the eGFP, and (c) Southern blot analysis. A complete homology was found between the Aequorea Victoria eGFP DNA and a 313-bp PCR product of extracted DNA from chick blood cells. Following insemination with sperm lipofected with p-hFSH, transgenic offspring were obtained for two generations as determined by detection of the transgene for human FSH (PCR) and expression of the gene (RT-PCR and quantitative real-time PCR) and the presence of the protein in blood (radioimmunoassay). Data demonstrate that lipofection of plasmid DNA with restriction enzyme is a highly efficient method for the production of transfected sperm to produce transgenic offspring by direct artificial insemination.

  14. 重组质粒pMG36e-nisI-gfp在乳酸菌中的应用%Application of Recombined Plasmid pMG36e-nisI-gfp in Lactic Acid Bacteria

    Institute of Scientific and Technical Information of China (English)

    代伟丽; 王艳萍; 王菁蕊; 白小佳

    2012-01-01

    本研究将带有nisI和gfp(绿色荧光蛋白)基因的乳酸菌表达栽体pMG36e-nisI-gfp转化至乳酸菌中,观察其在宿主内的稳定性.对重组菌进行了菌体形态、传代培养、质粒验证等研究,考察了该质粒的稳定性.结果显示:重组菌在不含抗生素的培养基中连续传代20代后,质粒丢失率低;菌体大小和形态基本不变;质粒经HindⅢ酶切后大小不变;GFP在第0、5、10、15和20代宿主菌中都可以表达,表达量没有明显差别,在SDS-PAGE中的带型一致;初步的动物实验验证了该质粒作为遗传标记的应用效果.说明该质粒在宿主菌中具有良好的稳定性.%A constitutive expression vector for lactic acid bacteria,named pMG36e-rnisl-gfp,was constructed first,using nisl as the selection marker and GFP as the reporter protein. In this work, the expression vector was electroporated into some LABs and its plasmid stability was evaluated. The results showed that the loss rate of the plasmid strains harboring pMG36e-nisl-gfp was still low even after 20 generations during the subculture in a liquid culture medium without antibiotics. The size and shape of the recombined strain did not change before and after subculture. The expression of GFP in the 0th, 5th, 10th, 15th and 20th generations showed no significant difference. The effect of pMG36e-isl-gfp as a reporter protein was proved in animal experiments. It was concluded that the plasmid pMG36e-nisl-gfp had good stability.

  15. Chromosomal Location and Expression of Green Fluorescent Protein (gfp) Gene in Microspore Derived Transgenic Barley (Hordeum vulgare L.)%转基因大麦中gfp基因的染色体位置及其表达

    Institute of Scientific and Technical Information of China (English)

    陈建民; Carlson A R; 万建民; Kasha K J

    2003-01-01

    通过对大麦小孢子进行基因枪轰击获得4株转绿色荧光蛋白基因(gfp)的植株(A、C、D、E),以gfp基因为探针进行荧光原位杂交(FISH)研究转化植株中转基因插入位置和基因表达.4个株系在染色体7L(5HL)的不同位置都有一个插入点,而E株系在染色体5S(7HS)还有第2个插入点.所有的转基因T0代植株都是半合子并在T1、T2代发生分离.D株系GFP未表达,但FISH和PCR分析表明gfp基因已成功插入其染色体.各株系在根尖和花粉中的GFP表达水平不同:C株系在花粉表达强而在根尖表达中等;A株系在花粉中等表达而在根尖表达较淡;E株系则在根尖高表达,花粉中等表达.A和C株系在根尖和花粉的GFP分离都表现单位点特性,而E株系的根尖分离表现重叠作用(15∶1)特征,但在花粉中表达GFP的频率低.PCR结果和3个分离株系的根尖表达结果一致.D和E株系的GFP表达不正常可能和gfp基因插入位置或基因的结构有关.%Four doubled haploid barley lines (A,C,D,E) derived from gfp (green fluorescent protein) transformation and selection following particle bombardment of microspores were studied for gene expression pattern and the location of genome inserts.The integration sites were detected by fluorescence in situ hybridization (FISH) using the gfp plasmid DNA as a probe.Plants from events A,C,D and E all have a single insert site on chromosome 7L(5HL) at different locations while line E has a second insert site on chromosome 5S(7HS).All original transgenic plants were hemizygous for the transgenes and segregated in the T1 and T2 generations.Although line D had no GFP expression,FISH and PCR could detect gfp gene on its chromosome in transformed plants.Expression levels of GFP varied with lines and tissues examined.Plants from line C showed good expression in pollen and an intermediate level in root tips.Plants from A have intermediate expression of GFP in the pollen and light expression in the

  16. Preparation of metallochelating microbubbles and study on their site-specific interaction with rGFP-HisTag as a model protein.

    Science.gov (United States)

    Lukáč, Róbert; Kauerová, Zuzana; Mašek, Josef; Bartheldyová, Eliška; Kulich, Pavel; Koudelka, Štěpán; Korvasová, Zina; Plocková, Jana; Papoušek, František; Kolář, František; Schmidt, Roland; Turánek, Jaroslav

    2011-04-19

    The histidine-metallochelating lipid complex is one of the smallest high affinity binding units used as tools for rapid noncovalent binding of histidine tagged molecules, especially recombinant proteins. The advantage of metallochelating complex over protein-ligand complexes (e.g., streptavidine-biotin, glutathiontransferase-glutathion) consists in its very low immunogenicity, if any. This concept for the construction of surface-modified metallochelating microbubbles was proved with recombinant green fluorescent protein (rGFP) containing 6His-tag. This protein is easy to be detected by various fluorescence techniques as flow cytometry and confocal microscopy. Microbubbles (MB) composed of DPPC with various contents of metallochelating lipid DOGS-NTA-Ni were prepared by intensive shaking of the liposome suspension under the atmosphere of sulfur hexafluoride. For this purpose, the instrument 3M ESPE CapMix was used. Various techniques (static light scattering, flow cytometry, and optical microscopy) were compared and used for the measurements of the size distribution of MB. All three methods demonstrated that the prepared MB were homogeneous in their size, and the mean diameter of the MB in various batches was within the range of 2.1-2.8 μm (the size range of 1-10 μm). The presence of large MB (8-10 μm) was marginal. Counting of MB revealed that the average amount of MB prepared of 10 mg of phospholipid equaled approximately 10(9) MB/mL. Lyophilized MB were prepared with saccharose as a cryoprotectant. These MB were shown to be stable both in vitro (the estimated half-live of the MB in bovine serum at 37 °C was 3-7 min) and in vivo (mouse). The stability of the MB was affected by molar content of DOGS-NTA-Ni. DPPC-based metallochelating MB provided a clear and very contrast image of the ventricular cavity soon after the injection. Site selective and stable binding of rGFP-HisTag (as a model of His-tagged protein) onto the surface of metallochelating MB was

  17. Combination therapy and evaluation of therapeutic effect in hepatocellular carcinoma cell using triple reporter genes; containing for NIS, HSV1-sr39tk and GFP

    Energy Technology Data Exchange (ETDEWEB)

    Lee, You La; Lee, Yong Jin; Ahn, Sohn Joo; Ahn, Byeong Cheol; Lee, Sang Woo; Yoo, Jeong Soo; Lee, Jae Tae [Kyungpook National University, Daegu (Korea, Republic of)

    2007-07-01

    To identify therapeutic effect after combine Sodium Iodine Symporter (NIS) and Mutant Herpes-simplex virus type 1 sr39tk (HSV1-sr39tk) expression in hepatocellular carcinoma cell, we transfected triple gene and investigated the properties of these gene ability in hepatocellular carcinoma cell line. After making vector with gene encoding a fusion protein comprised of HSV1-sr39tk and green florescence protein (GFP), to make triple reporter genes NIS gene was further fused to the vector using IRES vector. The vector expressing triple reporter gene was transfected to the Huh-7 cell line using liposome. Functions of hNIS and HSV1-sr39tk expression were confirmed by radio iodine uptake with and without perchlorate and [3H]-penciclovir (3-H PCV) uptake, respectively. To evaluate therapeutic effect in vitro, GCV and I-131 was treated in Huh-7/NTG cell and dual therapy performed. An animal imaging acquired using Optix and microPET in vivo. I-125 uptake was increased up to 100-fold compare to that of non-transfected cells. The transfected cell accumulated H-3 PCV up to 53 times higher at 2 hour than that of non-transfected cells. With fluorescence microscopy, green fluorescence was detected in the transfected cell. In cytotoxic studies, the cell viability of Huh-7/NTG cell was decreased to 41 % of control cell at 10ug/ml GCV concentrations. The survival rate of the Huh-7/NTG cell treated with I-131 decreased up to 16%. In I-131 and GCV dual therapy, Huh-7/NTG cell survival rate decreased up to 4%. In animal studies, Huh-7/NTG tumors showed higher uptake of 18F-FHBG and I-124 than Huh-7 tumors. GFP signal is also higher in Huh-7/NTG tumor than control. We successfully constructed a vector with delivery two therapeutic genes and one reporter gene and transfected the vector to a Huh-7 cell. The hepatocellular carcinoma cell transfected with the vector can be treated with GCV and I-131. The effect of dual gene therapy could be easily assessed by the optical reporter gene imaging.

  18. Validation of chemical compound library screening for transcriptional co-activator with PDZ-binding motif inhibitors using GFP-fused transcriptional co-activator with PDZ-binding motif.

    Science.gov (United States)

    Nagashima, Shunta; Maruyama, Junichi; Kawano, Shodai; Iwasa, Hiroaki; Nakagawa, Kentaro; Ishigami-Yuasa, Mari; Kagechika, Hiroyuki; Nishina, Hiroshi; Hata, Yutaka

    2016-06-01

    Transcriptional co-activator with PDZ-binding motif (TAZ) plays versatile roles in cell proliferation and differentiation. It is phosphorylated by large tumor suppressor kinases, the core kinases of the tumor-suppressive Hippo pathway. Phosphorylation induces the cytoplasmic accumulation of TAZ and its degradation. In human cancers, the deregulation of the Hippo pathway and gene amplification enhance TAZ activity. TAZ interacts with TEA domain family members (TEAD), and upregulates genes implicated in epithelial-mesenchymal transition. It also confers stemness to cancer cells. Thus, TAZ activation provides cancer cells with malignant properties and worsens the clinical prognosis. Therefore, TAZ attracts attention as a therapeutic target in cancer therapy. We applied 18 606 small chemical compounds to human osteosarcoma U2OS cells expressing GFP-fused TAZ (GFP-TAZ), monitored the subcellular localization of GFP-TAZ, and selected 33 compounds that shifted GFP-TAZ to the cytoplasm. Unexpectedly, only a limited number of compounds suppressed TAZ-mediated enhancement of TEAD-responsive reporter activity. Moreover, the compounds that weakened TEAD reporter activity did not necessarily decrease the unphosphorylated TAZ. In this study, we focused on three compounds that decreased both TEAD reporter activity and unphosphorylated TAZ, and treated several human cancer cells with these compounds. One compound did not show a remarkable effect, whereas the other two compounds compromised the cell viability in certain cancer cells. In conclusion, the GFP-TAZ-based assay can be used as the first screening for compounds that inhibit TAZ and show anticancer properties. To develop anticancer drugs, we need additional assays to select the compounds.

  19. Binding of PLCδ1PH-GFP to Ptdlns(4,5)P2 prevents inhibition of phospholipase C-mediated hydrolysis of Ptdlns(4,5)P2 by neomycin

    Institute of Scientific and Technical Information of China (English)

    Chuan WANG; Xiao-na DU; Qing-zhong JIA; Hai-lin ZHANG

    2005-01-01

    Aim: To investigate the effects of the pleckstrin homology (PH) domain of phospholipase Cδ1 (PLCδ1PH) on inhibition of phospholipase C (PLC)-mediated hydrolysis of phosphatidylinositol 4,5-bisphosphate [PtdIns(4,5)P2] by neomycin.Methods: A fusion construct of green fluorescent protein (GFP) and PLCδ1PH (PLCδ1PH-GFP), which is known to bind Ptdlns(4,5)P2 specifically, together with laser-scanning confocal microscopy, was used to trace PtdIns(4,5)P2 translocation.Results: Stimulation of the type 1 muscarinic receptor and the bradykinin 2 receptor induced a reversible PLCδ1PH-GFP translocation from the membrane to the cytosol in COS-7 cells. PLC inhibitor U73122 blocked the translocation.Wortmannin, a known PtdIns kinase inhibitor, did not affect the translocation induced by ACh, but blocked recovery after translocation, indicating that PtdIns(4,5)P2 hydrolysis occurs through receptor-mediated PLC activation.Neomycin, a commonly used phospholipase C blocker, failed to block the receptor-induced PLCδ1PH-GFP translocation, indicating that neomycin is unable to block PLC-mediated PtdIns(4,5)P2 hydrolysis. However, in the absence of PLCδ1PH-GFP expression, neomycin abolished the receptor-induced hydrolysis of PtdIns(4,5)P2 by PLC. Conclusion: Although PLCδ1PH and neomycin bind to PtdIns(4,5)P2 in a similar way, they have distinct effects on receptor-mediated activation of PLC and PtdIns(4,5)P2 hydrolysis.

  20. The use of a viral 2A sequence for the simultaneous over-expression of both the vgf gene and enhanced green fluorescent protein (eGFP) in vitro and in vivo

    Science.gov (United States)

    Lewis, Jo E.; Brameld, John M.; Hill, Phil; Barrett, Perry; Ebling, Francis J.P.; Jethwa, Preeti H.

    2015-01-01

    Introduction The viral 2A sequence has become an attractive alternative to the traditional internal ribosomal entry site (IRES) for simultaneous over-expression of two genes and in combination with recombinant adeno-associated viruses (rAAV) has been used to manipulate gene expression in vitro. New method To develop a rAAV construct in combination with the viral 2A sequence to allow long-term over-expression of the vgf gene and fluorescent marker gene for tracking of the transfected neurones in vivo. Results Transient transfection of the AAV plasmid containing the vgf gene, viral 2A sequence and eGFP into SH-SY5Y cells resulted in eGFP fluorescence comparable to a commercially available reporter construct. This increase in fluorescent cells was accompanied by an increase in VGF mRNA expression. Infusion of the rAAV vector containing the vgf gene, viral 2A sequence and eGFP resulted in eGFP fluorescence in the hypothalamus of both mice and Siberian hamsters, 32 weeks post infusion. In situ hybridisation confirmed that the location of VGF mRNA expression in the hypothalamus corresponded to the eGFP pattern of fluorescence. Comparison with old method The viral 2A sequence is much smaller than the traditional IRES and therefore allowed over-expression of the vgf gene with fluorescent tracking without compromising viral capacity. Conclusion The use of the viral 2A sequence in the AAV plasmid allowed the simultaneous expression of both genes in vitro. When used in combination with rAAV it resulted in long-term over-expression of both genes at equivalent locations in the hypothalamus of both Siberian hamsters and mice, without any adverse effects. PMID:26300182

  1. pIRES2-AcGFP1-CD真核表达载体构建及其在骨髓间充质干细胞中的表达%Construction of pIRES2-AcGFP1-CD eukaryotic expression plasmid and its expression in bone marrow mesenchymal stem cells

    Institute of Scientific and Technical Information of China (English)

    宋飞; 陈一曲; 马学虎; 葛丹; 刘天庆; 马郁芳; 崔占峰

    2008-01-01

    BACKGROUND: Bone marrow mesenchymal stem cells (BMSCs) are easily isolated and amplified, and facilitate the exogenous gene transfer and expression. In the human medicine, it is believed that BMSCs are ideal therapeutic cells and target cells in the gene therapy.OBJECTIVE: To investigate liposome-mediated cytosine deaminase (CD) gene transfecting rabbit BMSCs and its gene expression. DESIGN: A single sample observation. SETTING: Dalian Research and Development Center for Stem Cell and Tissue Engineering; Department of Biochemistry, College of Basic Medical Science, Dalian Medical University.MATERIALS: This study was performed at in the Dalian Research and Development Center for Stem Cell and Tissue Engineering; Department of Biochemistry, College of Basic Medical Science, Dalian Medical University from March 2006 to June 2007. New Zealand big-ear white rabbits of either gender, weighing 2.0-2.5 kg, with the age of 5 months old, were included in this study. METHODS: The CD gene was obtained from E.coli JM109 DNA by polymerase chain reaction (PCR). The fragment was cloned into pMD19-T vector. After restriction enzyme BamHI/XhoI digestion analysis and DNA sequence analysis, pIRES2-AcGFP1-CD eukaryotic expression plasmid was constructed. Meanwhile, BMSCs were harvested, cultured and identified. After enzyme digestion of eukaryotic expression plasmid, the rabbit BMSCs were transfected by Lipofectamine 2000-mediated method. Twenty-four hours after transfection, expression of green fluorescent protein was observed under an inverted fluorescent microscope. MAIN OUTCOME MEASURES: Construction of eukaryotic expression plasmid and identification of CD gene-transferred BMSCs. RESULTS: CD gene was cloned and connected to eukaryotic expression plasmid with green fluorescence. Twenty-four hours after transfecting rabbit BMSCs, it was found under an inverted microscope that under the excitation of 488 nm blue light, green fluorescence appeared in the pIRES2-AcGFP1-CD and pIRES2-AcGFP

  2. Prospective separation and transcriptome analyses of cortical projection neurons and interneurons based on lineage tracing by Tbr2 (Eomes)-GFP/Dcx-mRFP reporters.

    Science.gov (United States)

    Liu, Jiancheng; Wu, Xiwei; Zhang, Heying; Qiu, Runxiang; Yoshikawa, Kazuaki; Lu, Qiang

    2016-06-01

    In the cerebral cortex, projection neurons and interneurons work coordinately to establish neural networks for normal cortical functions. While the specific mechanisms that control productions of projection neurons and interneurons are beginning to be revealed, a global characterization of the molecular differences between these two neuron types is crucial for a more comprehensive understanding of their developmental specifications and functions. In this study, using lineage tracing power of combining Tbr2(Eomes)-GFP and Dcx-mRFP reporter mice, we prospectively separated intermediate progenitor cell (IPC)-derived neurons (IPNs) from non-IPC-derived neurons (non-IPNs) of the embryonic cerebral cortex. Molecular characterizations revealed that IPNs and non-IPNs were enriched with projection neurons and interneurons, respectively. Expression profiling documented cell-specific genes including differentially expressed transcriptional regulators that might be involved in cellular specifications, for instance, our data found that SOX1 and SOX2, which were known for important functions in neural stem/progenitor cells, continued to be expressed by interneurons but not by projection neurons. Transcriptome analyses of cortical neurons isolated at different stages of neurogenesis revealed distinct temporal patterns of expression of genes involved in early-born or late-born neuron specification. These data present a resource useful for further investigation of the molecular regulations and functions of projection neurons and interneurons.

  3. OBP-401-GFP telomerase-dependent adenovirus illuminates and kills high-metastatic more effectively than low-metastatic triple-negative breast cancer in vitro.

    Science.gov (United States)

    Yano, S; Takehara, K; Kishimoto, H; Tazawa, H; Urata, Y; Kagawa, S; Bouvet, M; Fujiwara, T; Hoffman, R M

    2017-02-01

    We previously described the development of a highly-invasive, triple-negative breast cancer (TNBC) variant using serial orthotopic implantation of MDA-MB-231 human breast cancer in nude mice. The isolated variant is highly invasive in the mammary gland and metastasized to lymph nodes in 10 of 12 mice compared with 2 of 12 of the parental cell line. OBP-401 is a telomerase-dependent cancer-specific, green fluorescent protein (GFP)-expressing adenovirus. OBP-401 was used to infect parental MDA-MB-231P cells and high-metastatic MDA-MB-231H and MDA-MB-231HLN isolated from a lymph node metastasis and MDA-MB-231HLM isolated from a lung metastasis. Time-course imaging showed that OBP-401 labeled MDA-MB-231HP, MDA-MB-231HLN, and MDA-MB-231HLM cells more brightly than MDA-MB-231 parental cells. OBP-401 killed MDA-MB-231H, MDA-MB-231HLN, and MDA-MB-231HLM cells more efficiently than MDA-MB-231P parental cells. These results indicate that OBP-401 could infect, label and then kill high-metastatic MDA-MB-231 more efficiently than low-metastatic MDA-MB-231.

  4. FIB/SEM technology and high-throughput 3D reconstruction of dendritic spines and synapses in GFP-labeled adult-generated neurons.

    Science.gov (United States)

    Bosch, Carles; Martínez, Albert; Masachs, Nuria; Teixeira, Cátia M; Fernaud, Isabel; Ulloa, Fausto; Pérez-Martínez, Esther; Lois, Carlos; Comella, Joan X; DeFelipe, Javier; Merchán-Pérez, Angel; Soriano, Eduardo

    2015-01-01

    The fine analysis of synaptic contacts is usually performed using transmission electron microscopy (TEM) and its combination with neuronal labeling techniques. However, the complex 3D architecture of neuronal samples calls for their reconstruction from serial sections. Here we show that focused ion beam/scanning electron microscopy (FIB/SEM) allows efficient, complete, and automatic 3D reconstruction of identified dendrites, including their spines and synapses, from GFP/DAB-labeled neurons, with a resolution comparable to that of TEM. We applied this technology to analyze the synaptogenesis of labeled adult-generated granule cells (GCs) in mice. 3D reconstruction of dendritic spines in GCs aged 3-4 and 8-9 weeks revealed two different stages of dendritic spine development and unexpected features of synapse formation, including vacant and branched dendritic spines and presynaptic terminals establishing synapses with up to 10 dendritic spines. Given the reliability, efficiency, and high resolution of FIB/SEM technology and the wide use of DAB in conventional EM, we consider FIB/SEM fundamental for the detailed characterization of identified synaptic contacts in neurons in a high-throughput manner.

  5. FIB/SEM technology and high-throughput 3D reconstruction of dendritic spines and synapses in GFP-labeled adult-generated neurons

    Science.gov (United States)

    Bosch, Carles; Martínez, Albert; Masachs, Nuria; Teixeira, Cátia M.; Fernaud, Isabel; Ulloa, Fausto; Pérez-Martínez, Esther; Lois, Carlos; Comella, Joan X.; DeFelipe, Javier; Merchán-Pérez, Angel; Soriano, Eduardo

    2015-01-01

    The fine analysis of synaptic contacts is usually performed using transmission electron microscopy (TEM) and its combination with neuronal labeling techniques. However, the complex 3D architecture of neuronal samples calls for their reconstruction from serial sections. Here we show that focused ion beam/scanning electron microscopy (FIB/SEM) allows efficient, complete, and automatic 3D reconstruction of identified dendrites, including their spines and synapses, from GFP/DAB-labeled neurons, with a resolution comparable to that of TEM. We applied this technology to analyze the synaptogenesis of labeled adult-generated granule cells (GCs) in mice. 3D reconstruction of dendritic spines in GCs aged 3–4 and 8–9 weeks revealed two different stages of dendritic spine development and unexpected features of synapse formation, including vacant and branched dendritic spines and presynaptic terminals establishing synapses with up to 10 dendritic spines. Given the reliability, efficiency, and high resolution of FIB/SEM technology and the wide use of DAB in conventional EM, we consider FIB/SEM fundamental for the detailed characterization of identified synaptic contacts in neurons in a high-throughput manner. PMID:26052271

  6. Appearance of actin microfilament 'twin peaks' in mitosis and their function in cell plate formation, as visualized in tobacco BY-2 cells expressing GFP-fimbrin.

    Science.gov (United States)

    Sano, Toshio; Higaki, Takumi; Oda, Yoshihisa; Hayashi, Tomomi; Hasezawa, Seiichiro

    2005-11-01

    The actin cytoskeleton of higher plants plays an essential role in plant morphogenesis and in maintaining various cellular activities. In this study we established a tobacco BY-2 cell line, stably transformed with a GFP-fimbrin actin-binding domain (ABD) 2 construct, that allows visualization of actin microfilaments (MFs) in living cells. Using this cell line, designated BY-GF11, we performed time-sequential observations of MF dynamics during cell-cycle progression. Detailed analyses revealed the appearance of a broad MF band in the late G2 phase that separated to form a structure corresponding to the so-called actin-depleted zone (ADZ) in mitosis. In BY-GF11, the MF structure at the cell cortex in mitosis appeared to form two bands rather than the ADZ. Measurements of fluorescent intensities of the cell cortex indicated an MF distribution that resembled two peaks, and we therefore named the structure MF 'twin peaks' (MFTP). The cell plate formed exactly within the valley between the MFTP at cytokinesis, and this cell-plate guidance was distorted by disruption of the MFTP by an inhibitor of actin polymerization. These results suggest that the MFTP originates from the broad MF band in the G2 phase and functions as a marker of cytokinesis.

  7. Marking Embryonic Stem Cells with a 2A Self-Cleaving Peptide: A NKX2-5 Emerald GFP BAC Reporter

    Science.gov (United States)

    Hsiao, Edward C.; Yoshinaga, Yuko; Nguyen, Trieu D.; Musone, Stacy L.; Kim, Judy E.; Swinton, Paul; Espineda, Isidro; Manalac, Carlota; deJong, Pieter J.; Conklin, Bruce R.

    2008-01-01

    Background Fluorescent reporters are useful for assaying gene expression in living cells and for identifying and isolating pure cell populations from heterogeneous cultures, including embryonic stem (ES) cells. Multiple fluorophores and genetic selection markers exist; however, a system for creating reporter constructs that preserve the regulatory sequences near a gene's native ATG start site has not been widely available. Methodology Here, we describe a series of modular marker plasmids containing independent reporter, bacterial selection, and eukaryotic selection components, compatible with both Gateway recombination and lambda prophage bacterial artificial chromosome (BAC) recombineering techniques. A 2A self-cleaving peptide links the reporter to the native open reading frame. We use an emerald GFP marker cassette to create a human BAC reporter and ES cell reporter line for the early cardiac marker NKX2-5. NKX2-5 expression was detected in differentiating mouse ES cells and ES cell-derived mice. Conclusions Our results describe a NKX2-5 ES cell reporter line for studying early events in cardiomyocyte formation. The results also demonstrate that our modular marker plasmids could be used for generating reporters from unmodified BACs, potentially as part of an ES cell reporter library. PMID:18596956

  8. A system for the measurement of gene targeting efficiency in human cell lines using an antibiotic resistance-GFP fusion gene.

    Science.gov (United States)

    Konishi, Yuko; Karnan, Sivasundaram; Takahashi, Miyuki; Ota, Akinobu; Damdindorj, Lkhagvasuren; Hosokawa, Yoshitaka; Konishi, Hiroyuki

    2012-09-01

    Gene targeting in a broad range of human somatic cell lines has been hampered by inefficient homologous recombination. To improve this technology and facilitate its widespread application, it is critical to first have a robust and efficient research system for measuring gene targeting efficiency. Here, using a fusion gene consisting of hygromycin B phosphotransferase and 3'-truncated enhanced GFP (HygR-5' EGFP) as a reporter gene, we created a molecular system monitoring the ratio of homologous to random integration (H/R ratio) of targeting vectors into the genome. Cell clones transduced with a reporter vector containing HygR-5' EGFP were efficiently established from two human somatic cell lines. Established HygR-5' EGFP reporter clones retained their capacity to monitor gene targeting efficiency for a longer duration than a conventional reporter system using an unfused 5' EGFP gene. With the HygR-5' EGFP reporter system, we reproduced previous findings of gene targeting frequency being up-regulated by the use of an adeno-associated viral (AAV) backbone, a promoter-trap system, or a longer homology arm in a targeting vector, suggesting that this system accurately monitors H/R ratio. Thus, our HygR-5' EGFP reporter system will assist in the development of an efficient AAV-based gene targeting technology.

  9. Ketamine alters cortical integration of GABAergic interneurons and induces long-term sex-dependent impairments in transgenic Gad67-GFP mice

    Science.gov (United States)

    Aligny, C; Roux, C; Dourmap, N; Ramdani, Y; Do-Rego, J-C; Jégou, S; Leroux, P; Leroux-Nicollet, I; Marret, S; Gonzalez, B J

    2014-01-01

    Ketamine, a non-competitive N-methyl-D-aspartate (NMDA) antagonist, widely used as an anesthetic in neonatal pediatrics, is also an illicit drug named Super K or KitKat consumed by teens and young adults. In the immature brain, despite several studies indicating that NMDA antagonists are neuroprotective against excitotoxic injuries, there is more and more evidence indicating that these molecules exert a deleterious effect by suppressing a trophic function of glutamate. In the present study, we show using Gad67-GFP mice that prenatal exposure to ketamine during a time-window in which GABAergic precursors are migrating results in (i) strong apoptotic death in the ganglionic eminences and along the migratory routes of GABAergic interneurons; (ii) long-term deficits in interneuron density, dendrite numbers and spine morphology; (iii) a sex-dependent deregulation of γ-aminobutyric acid (GABA) levels and GABA transporter expression; (iv) sex-dependent changes in the response to glutamate-induced calcium mobilization; and (v) the long-term sex-dependent behavioral impairment of locomotor activity. In conclusion, using a preclinical approach, the present study shows that ketamine exposure during cortical maturation durably affects the integration of GABAergic interneurons by reducing their survival and differentiation. The resulting molecular, morphological and functional modifications are associated with sex-specific behavioral deficits in adults. In light of the present data, it appears that in humans, ketamine could be deleterious for the development of the brain of preterm neonates and fetuses of addicted pregnant women. PMID:24991763

  10. FIB/SEM technology and high-throughput 3D reconstruction of dendritic spines and synapses in GFP-labeled adult-generated neurons

    Directory of Open Access Journals (Sweden)

    Carles eBosch

    2015-05-01

    Full Text Available The fine analysis of synaptic contacts is usually performed using transmission electron microscopy (TEM and its combination with neuronal labeling techniques. However, the complex 3D architecture of neuronal samples calls for their reconstruction from serial sections. Here we show that focused ion beam/scanning electron microscopy (FIB/SEM allows efficient, complete, and automatic 3D reconstruction of identified dendrites, including their spines and synapses, from GFP/DAB-labeled neurons, with a resolution comparable to that of TEM. We applied this technology to analyze the synaptogenesis of labeled adult-generated granule cells (GCs in mice. 3D reconstruction of spines in GCs aged 3–4 and 8–9 weeks revealed two different stages of spine development and unexpected features of synapse formation, including vacant and branched spines and presynaptic terminals establishing synapses with up to 10 spines. Given the reliability, efficiency, and high resolution of FIB/SEM technology and the wide use of DAB in conventional EM, we consider FIB/SEM fundamental for the detailed characterization of identified synaptic contacts in neurons in a high-throughput manner.

  11. Construction and identification of the PTEN expression plasmid GFP-PTEN%PTEN基因真核表达载体的构建及在MG63中表达

    Institute of Scientific and Technical Information of China (English)

    徐生林; 胡勇; 金问森; 王明明; 王京; 王娟

    2012-01-01

    目的 构建PTEN基因真核表达载体,为PTEN基因功能研究提供工具.方法 从人淋巴细胞中提取总RNA,采用反转录-聚合酶链反应扩增PTEN基因编码区,将其克隆入pEGFP-N1载体中.通过聚合酶链反应、酶切和DNA测序鉴定所构建的载体.脂质体包裹重组载体转染骨肉瘤MG63细胞,RT-PCR和Western blot检测转染后的骨肉瘤MG63细胞中PTEN基因mRNA和蛋白质表达情况.结果 经过限制性酶切和测序鉴定得到重组子GFP-PTEN大小符合,序列与GenBank中人DNA的PTEN基因(NM_000314)完全一致.转染GFP-PTEN基因的骨肉瘤MG63细胞中PTEN基因mRNA和蛋白高水平表达.结论 成功地构建了PTEN基因真核表达载体.%Objective To construct an eukaryotic expression vector for phosphatase and tensin homology deletedon chromosome ten( PTEN ) gene lymphocytes and provide a tool for studying of PTEN gene function. Methods The total RNAs were isolated from human lymphocytes. The cDNA of PTEN gene was amplified by reverse transcription polymerase chain reaction( RT-PCR ). After purification, the gene was cloned into pEGFP-Nl vector. The recombi-nant plasmid was identified by enzyme digestion and DNA sequencing. Then GFP and GFP-PTEN were respectively transfected into the osteosaocoma cell line( MG63 )with Lipofectamine 2000. The mRNA and protein expression level of PTEN gene in each cell group was detected by fluorescent quantitative RT-PCR and Western blot. Results Re-combinant vector of GFP-PTEN was constructed successfully. After transfection with GFP-PTEN, the mRNA and protein expression level of PTEN rose in MG63 cells. There were significant differences between transfected group and control group. Conclusion The eukaryotic expression vector of PTEN gene has been successfully constructed, which may provide a basis for further researches.

  12. Study on the roles of HLA-A gene polymorphism in the susceptibility and symptom of SARS-Coronavirus infection%HLA-A基因多态性与SARS易感性及症状关系的研究

    Institute of Scientific and Technical Information of China (English)

    何丽; 魏茂提; 王世鑫; 胡役兰

    2011-01-01

    Objective:To study the association between HLA-A gene polym orphsm and the susceptibility and symptom of SARS-Coroavirus infection in Northern Chinese Han ethnics.Methods:HLA-A were typed in 53 SARS cases,44 high risks and 77 controls using PCR-SBT m ethods in two case-control studies.Data were analyzed using SPSS version 11.5 and chisquares and OR were used to show the differences and association .Results:The frequency of HLA-A * 2453 allele in SARS patients was markedly higher than that of the high risk care workers(P=0.039,0R=4.479,95%CI 0.95-21.015).How ever,the frequency of HLA-A * 2444 allele in SARS patients was lower than that of the health control( P=0.029 ) .There was no significant difference of the distribution of HLA-A allele frequency in mild cases and severe cases.Conclusion :Genotype of HLA-A * 2453 may be one risk factor for infection of SARS-Cov ,how ever,HLA-A * 2444 may be protect factor for it infection .The severity of SARS may not relate with the genotype of HLA-A.%目的:研究中国北方汉族人群HLA-A基因多态性与SARS-Cov易感性及症状的关系.方法:采用病例-对照研究设计,应用PCR-SBT的研究方法对53例SARS患者、44例高危人群和77例健康人员的HLA-A位点等位基因型分布进行研究,运用SPSS11.5软件包进行统计分析,组间比较采用χ2检验,计算比值比(OR)及其95%可信区间(95%CI).结果:与高危人群比较,SARS病人 HLA-A*2453(P=0.039,OR=4.479,95%CI 0.955~21.015)基因型出现频率较高,两者有统计学意义;与健康人群比较,SARS病人HLA-A*2444(P=0.029)基因型频率显著减低;SARS患者轻症组和重症组的HLA-A位点的等位基因频率分布相比较未发现统计学差异(P>0.05).结论:我国华北地区汉族人群中HLA-A*2453可能与SARS的易感性相关,而等位基因HLA-A*2444可能具有保护作用.HLA-A基因多态性与SARS患者病情严重程度可能无关.

  13. Deciphering the Niches of Colonisation of Vitis vinifera L. by the Esca-Associated Fungus Phaeoacremonium aleophilum Using a gfp Marked Strain and Cutting Systems

    Science.gov (United States)

    Pierron, Romain; Gorfer, Markus; Berger, Harald; Jacques, Alban; Sessitsch, Angela; Strauss, Joseph; Compant, Stéphane

    2015-01-01

    Introduction Esca disease has become a major threat for viticulture. Phaeoacremonium aleophilum is considered a pioneer of the esca complex pathosystem, but its colonisation behaviour inside plants remains poorly investigated. Material and Methods In this study, P. aleophilum::gfp7 colonisation was assessed six and twelve weeks post-inoculation in two different types of tissues: in the node and the internode of one year-old rooted cuttings of Cabernet Sauvignon. These processes of colonisation were compared with the colonisation by the wild-type strain using a non-specific lectin probe Alexa Fluor 488-WGA. Results Data showed that six weeks post-inoculation of the internode, the fungus had colonised the inoculation point, the bark and xylem fibres. Bark, pith and xylem fibres were strongly colonised by the fungus twelve weeks post-inoculation and it can progress up to 8 mm from the point of inoculation using pith, bark and fibres. P. aleophilum was additionally detected in the lumen of xylem vessels in which tyloses blocked its progression. Different plant responses in specific tissues were additionally visualised. Inoculation of nodes led to restricted colonisation of P. aleophilum and this colonisation was associated with a plant response six weeks post-inoculation. The fungus was however detected in xylem vessels, bark and inside the pith twelve weeks post-inoculation. Conclusions These results demonstrate that P. aleophilum colonisation can vary according to the type of tissues and the type of spread using pith, bark and fibres. Woody tissues can respond to the injury and to the presence of this fungus, and xylem fibres play a key role in the early colonisation of the internode by P. aleophilum before the fungus can colonise xylem vessels. PMID:26061034

  14. Deciphering the Niches of Colonisation of Vitis vinifera L. by the Esca-Associated Fungus Phaeoacremonium aleophilum Using a gfp Marked Strain and Cutting Systems.

    Directory of Open Access Journals (Sweden)

    Romain Pierron

    Full Text Available Esca disease has become a major threat for viticulture. Phaeoacremonium aleophilum is considered a pioneer of the esca complex pathosystem, but its colonisation behaviour inside plants remains poorly investigated.In this study, P. aleophilum::gfp7 colonisation was assessed six and twelve weeks post-inoculation in two different types of tissues: in the node and the internode of one year-old rooted cuttings of Cabernet Sauvignon. These processes of colonisation were compared with the colonisation by the wild-type strain using a non-specific lectin probe Alexa Fluor 488-WGA.Data showed that six weeks post-inoculation of the internode, the fungus had colonised the inoculation point, the bark and xylem fibres. Bark, pith and xylem fibres were strongly colonised by the fungus twelve weeks post-inoculation and it can progress up to 8 mm from the point of inoculation using pith, bark and fibres. P. aleophilum was additionally detected in the lumen of xylem vessels in which tyloses blocked its progression. Different plant responses in specific tissues were additionally visualised. Inoculation of nodes led to restricted colonisation of P. aleophilum and this colonisation was associated with a plant response six weeks post-inoculation. The fungus was however detected in xylem vessels, bark and inside the pith twelve weeks post-inoculation.These results demonstrate that P. aleophilum colonisation can vary according to the type of tissues and the type of spread using pith, bark and fibres. Woody tissues can respond to the injury and to the presence of this fungus, and xylem fibres play a key role in the early colonisation of the internode by P. aleophilum before the fungus can colonise xylem vessels.

  15. Is salamander limb regeneration really perfect? Anatomical and morphogenetic analysis of forelimb muscle regeneration in GFP-transgenic axolotls as a basis for regenerative, developmental, and evolutionary studies.

    Science.gov (United States)

    Diogo, R; Nacu, E; Tanaka, E M

    2014-06-01

    The axolotl Ambystoma mexicanum is one of the most commonly used model organisms in developmental and regenerative studies because it can reconstitute what is believed to be a completely normal anatomical and functional forelimb/hindlimb after amputation. However, to date it has not been confirmed whether each regenerated forelimb muscle is really a "perfect" copy of the original muscle. This study describes the regeneration of the arm, forearm, hand, and some pectoral muscles (e.g., coracoradialis) in transgenic axolotls that express green fluorescent protein (GFP) in muscle fibers. The observations found that: (1) there were muscle anomalies in 43% of the regenerated forelimbs; (2) however, on average in each regenerated forelimb there are anomalies in only 2.5% of the total number of muscles examined, and there were no significant differences observed in the specific insertion and origin of the other muscles analyzed; (3) one of the most notable and common anomalies (seen in 35% of the regenerated forelimbs) was the presence of a fleshy coracoradialis at the level of the arm; this is a particularly outstanding configuration because in axolotls and in urodeles in general this muscle only has a thin tendon at the level of the arm, and the additional fleshy belly in the regenerated arms is strikingly similar to the fleshy biceps brachii of amniotes, suggesting a remarkable parallel between a regeneration defect and a major phenotypic change that occurred during tetrapod limb evolution; (4) during forelimb muscle regeneration there was a clear proximo-distal and radio-ulnar morphogenetic gradient, as seen in normal development, but also a ventro-dorsal gradient in the order of regeneration, which was not previously described in the literature. These results have broader implications for regenerative, evolutionary, developmental and morphogenetic studies. Copyright © 2014 Wiley Periodicals, Inc.

  16. Development of an efficient genetic manipulation strategy for sequential gene disruption and expression of different heterologous GFP genes in Candida tropicalis.

    Science.gov (United States)

    Zhang, Lihua; Chen, Xianzhong; Chen, Zhen; Wang, Zezheng; Jiang, Shan; Li, Li; Pötter, Markus; Shen, Wei; Fan, You

    2016-11-01

    The diploid yeast Candida tropicalis, which can utilize n-alkane as a carbon and energy source, is an attractive strain for both physiological studies and practical applications. However, it presents some characteristics, such as rare codon usage, difficulty in sequential gene disruption, and inefficiency in foreign gene expression, that hamper strain improvement through genetic engineering. In this work, we present a simple and effective method for sequential gene disruption in C. tropicalis based on the use of an auxotrophic mutant host defective in orotidine monophosphate decarboxylase (URA3). The disruption cassette, which consists of a functional yeast URA3 gene flanked by a 0.3 kb gene disruption auxiliary sequence (gda) direct repeat derived from downstream or upstream of the URA3 gene and of homologous arms of the target gene, was constructed and introduced into the yeast genome by integrative transformation. Stable integrants were isolated by selection for Ura(+) and identified by PCR and sequencing. The important feature of this construct, which makes it very attractive, is that recombination between the flanking direct gda repeats occurs at a high frequency (10(-8)) during mitosis. After excision of the URA3 marker, only one copy of the gda sequence remains at the recombinant locus. Thus, the resulting ura3 strain can be used again to disrupt a second allelic gene in a similar manner. In addition to this effective sequential gene disruption method, a codon-optimized green fluorescent protein-encoding gene (GFP) was functionally expressed in C. tropicalis. Thus, we propose a simple and reliable method to improve C. tropicalis by genetic manipulation.

  17. TRH-receptor mobility and function in intact and cholesterol-depleted plasma membrane of HEK293 cells stably expressing TRH-R-eGFP.

    Science.gov (United States)

    Brejchová, Jana; Sýkora, Jan; Ostašov, Pavel; Merta, Ladislav; Roubalová, Lenka; Janáček, Jiří; Hof, Martin; Svoboda, Petr

    2015-03-01

    Here we investigated the effect of disruption of plasma membrane integrity by cholesterol depletion on thyrotropin-releasing hormone receptor (TRH-R) surface mobility in HEK293 cells stably expressing TRH-R-eGFP fusion protein (VTGP cells). Detailed analysis by fluorescence recovery after photobleaching (FRAP) in bleached spots of different sizes indicated that cholesterol depletion did not result in statistically significant alteration of mobile fraction of receptor molecules (Mf). The apparent diffusion coefficient (Dapp) was decreased, but this decrease was detectable only under the special conditions of screening and calculation of FRAP data. Analysis of mobility of receptor molecules by raster image correlation spectroscopy (RICS) did not indicate any significant difference between control and cholesterol-depleted cells. Results of our FRAP and RICS experiments may be collectively interpreted in terms of a "membrane fence" model which regards the plasma membrane of living cells as compartmentalized plane where lateral diffusion of membrane proteins is limited to restricted areas by cytoskeleton constraints. Hydrophobic interior of plasma membrane, studied by steady-state and time-resolved fluorescence anisotropy of hydrophobic membrane probe DPH, became substantially more "fluid" and chaotically organized in cholesterol-depleted cells. Decrease of cholesterol level impaired the functional coupling between the receptor and the cognate G proteins of Gq/G11 family. the presence of an unaltered level of cholesterol in the plasma membrane represents an obligatory condition for an optimum functioning of TRH-R signaling cascade. The decreased order and increased fluidity of hydrophobic membrane interior suggest an important role of this membrane area in TRH-R-Gq/G11α protein coupling. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. Gene expression in tumor cells and stroma in dsRed 4T1 tumors in eGFP-expressing mice with and without enhanced oxygenation

    Directory of Open Access Journals (Sweden)

    Moen Ingrid

    2012-01-01

    Full Text Available Abstract Background The tumor microenvironment is pivotal in tumor progression. Thus, we aimed to develop a mammary tumor model to elucidate molecular characteristics in the stroma versus the tumor cell compartment by global gene expression. Secondly, since tumor hypoxia influences several aspects of tumor pathophysiology, we hypothesized that hyperoxia might have an inhibitory effect on tumor growth per se. Finally, we aimed to identify differences in gene expression and key molecular mechanisms, both in the native state and following treatment. Methods 4T1 dsRed breast cancer cells were injected into eGFP expressing NOD/SCID mice. Group 1 was exposed to 3 intermittent HBO treatments (Day 1, 4 and 7, Group 2 to 7 daily HBO treatments (both 2.5bar, 100% O2, à 90 min, whereas the controls were exposed to a normal atmosphere. Tumor growth, histology, vascularisation, cell proliferation, cell death and metastasis were assessed. Fluorescence-activated cell sorting was used to separate tumor cells from stromal cells prior to gene expression analysis. Results The purity of sorted cells was verified by fluorescence microscopy. Gene expression profiling demonstrated that highly expressed genes in the untreated tumor stroma included constituents of the extracellular matrix and matrix metalloproteinases. Tumor growth was significantly inhibited by HBO, and the MAPK pathway was found to be significantly reduced. Immunohistochemistry indicated a significantly reduced microvessel density after intermittent HBO, whereas daily HBO did not show a similar effect. The anti-angiogenic response was reflected in the expression trends of angiogenic factors. Conclusions The present in vivo mammary tumor model enabled us to separate tumor and stromal cells, and demonstrated that the two compartments are characterized by distinct gene expressions, both in the native state and following HBO treatments. Furthermore, hyperoxia induced a significant tumor growth

  19. 绿色荧光蛋白探针标记的 MIM-I-BAR 基因构建和表达%Construction and expression of GFP conjugated MIM-I-BAR

    Institute of Scientific and Technical Information of China (English)

    曹萌; 常维维; 许阳; 方琳静; 刘袁; 顾宁

    2015-01-01

    为制备可视化的转移消失蛋白(MIM)的 I-BAR 结构域重组体,克隆了顺联绿色荧光蛋白(GFP)探针编码序列的 MIM-I-BAR 基因.在6xHis 标签原核表达质粒上成功构建了 DNA 序列.同时,实现了未标记荧光探针基因的 MIM-I-BAR 质粒的构建以作实验对照.成功转染至 BL21(DE3)大肠杆菌细胞后,GFP 偶联的 MIM-I-BAR (MIM-I-BAR-GFP)蛋白表现出很强的可视荧光,该表达产物可方便的通过目测、荧光显微镜、免疫印迹和紫外可见分光光度计等多种手段进行检测.此外,在考察不同条件下的蛋白表达效率过程中发现,带有 GFP 探针的 MIM-I-BAR 重组蛋白在温度为10℃时产率最高,而并非37℃.这一特征与非荧光标记的 MIM-I-BAR 明显不同.研究证实该最佳表达温度条件适用于重组蛋白产品中量制备.所开发的带有荧光探针的 MIM-I-BAR 蛋白产品及其制备工艺在科学研究、生物医学应用以及药物开发过程中均有较高的应用价值.%To achieve a visible inverse Bin-amphiphysin-Rvs (I-BAR)domain recombinant of missing in metastasis (MIM) protein,the green fluorescent protein (GFP)encoding gene was cloned at the terminal of MIM-I-BAR as a probe.The DNA was successfully constructed on a 6xHis-tagged prokaryotic expression plasmid.The non-GFP labeled MIM-I-BAR encoding plasmid was also constructed as a control. Being successfully transformed into BL21 (DE3 )cells,the GFP-conjugated MIM-I-BAR (MIM-I-BAR-GFP ) exhibits strong visible fluorescence,and the expression product can be easily detected by visual inspection, a fluorescence microscope, Western blot or ultraviolet and visible spectrophotometer. Moreover, examination of expression efficiency under various culture conditions revealed that the MIM-I-BAR-GFP gene has a high protein yield at 10 ℃,but not at the culture temperature of 37 ℃.This property is much different from that of the non

  20. FOXN1 (GFP/w) reporter hESCs enable identification of integrin-β4, HLA-DR, and EpCAM as markers of human PSC-derived FOXN1(+) thymic epithelial progenitors.

    Science.gov (United States)

    Soh, Chew-Li; Giudice, Antonietta; Jenny, Robert A; Elliott, David A; Hatzistavrou, Tanya; Micallef, Suzanne J; Kianizad, Korosh; Seach, Natalie; Zúñiga-Pflücker, Juan Carlos; Chidgey, Ann P; Trounson, Alan; Nilsson, Susan K; Haylock, David N; Boyd, Richard L; Elefanty, Andrew G; Stanley, Edouard G

    2014-06-01

    Thymic epithelial cells (TECs) play a critical role in T cell maturation and tolerance induction. The generation of TECs from in vitro differentiation of human pluripotent stem cells (PSCs) provides a platform on which to study the mechanisms of this interaction and has implications for immune reconstitution. To facilitate analysis of PSC-derived TECs, we generated hESC reporter lines in which sequences encoding GFP were targeted to FOXN1, a gene required for TEC development. Using this FOXN1 (GFP/w) line as a readout, we developed a reproducible protocol for generating FOXN1-GFP(+) thymic endoderm cells. Transcriptional profiling and flow cytometry identified integrin-β4 (ITGB4, CD104) and HLA-DR as markers that could be used in combination with EpCAM to selectively purify FOXN1(+) TEC progenitors from differentiating cultures of unmanipulated PSCs. Human FOXN1(+) TEC progenitors generated from PSCs facilitate the study of thymus biology and are a valuable resource for future applications in regenerative medicine.

  1. FOXN1GFP/w Reporter hESCs Enable Identification of Integrin-β4, HLA-DR, and EpCAM as Markers of Human PSC-Derived FOXN1+ Thymic Epithelial Progenitors

    Directory of Open Access Journals (Sweden)

    Chew-Li Soh

    2014-06-01

    Full Text Available Thymic epithelial cells (TECs play a critical role in T cell maturation and tolerance induction. The generation of TECs from in vitro differentiation of human pluripotent stem cells (PSCs provides a platform on which to study the mechanisms of this interaction and has implications for immune reconstitution. To facilitate analysis of PSC-derived TECs, we generated hESC reporter lines in which sequences encoding GFP were targeted to FOXN1, a gene required for TEC development. Using this FOXN1GFP/w line as a readout, we developed a reproducible protocol for generating FOXN1-GFP+ thymic endoderm cells. Transcriptional profiling and flow cytometry identified integrin-β4 (ITGB4, CD104 and HLA-DR as markers that could be used in combination with EpCAM to selectively purify FOXN1+ TEC progenitors from differentiating cultures of unmanipulated PSCs. Human FOXN1+ TEC progenitors generated from PSCs facilitate the study of thymus biology and are a valuable resource for future applications in regenerative medicine.

  2. Treatment of optic nerve injury by transplanting hBDNF-GFP gene transfected neural stem cells%人脑源性神经营养因子基因转染神经干细胞治疗大鼠视神经损伤

    Institute of Scientific and Technical Information of China (English)

    刘勇; 陈二涛; 冯东福; 潘栋超; 汪洋

    2009-01-01

    目的 探讨转染人脑源性神经营养因子(brain-derived neurotrophic factor,hBDNF)-绿色荧光蛋白(GFP)基因神经干细胞体内移植后在视神经损伤大鼠视网膜内的存活、迁移和分化情况,以及其对视神经损伤后视网膜神经节细胞(retinal ganglion cells,RGCs)存活的影响.方法 (1)取30只SD大鼠制作右眼视神经部分损伤模型,采用随机数字表法随机均分成两组,分别于玻璃体腔内移植GFP基因转染神经干细胞(GFP-NSCs)、hBDNF和GFP双基因转染神经干细胞(hBDNF-GFP-NSCs).8周后处死大鼠,取右眼眼球做冰冻切片,然后分别用胸腺细胞表面糖蛋白(Thy1.1)、胶质纤维酸性蛋白(GFAP)、β-微管蛋白(β-tubulin)、视紫红质(rhodopsin)抗体进行免疫标记,观察移植细胞的迁移分化情况.(2)取30只SD大鼠制作右眼视神经部分损伤模型,随机均分为三组:损伤组、GFP组、BDNF组.损伤组大鼠玻璃体腔内注射等渗盐水,而GFP组、BDNF组则分别于玻璃体腔内移植GFP-NSCs和hBDNF-GFP-NSCs,每只眼球玻璃体腔内移植5×104个细胞.8周后处死大鼠,取右侧眼球视网膜铺片,行Thy1.1免疫荧光染色后,荧光显微镜下观察计数RGCs细胞数量.结果 (1)移植后,两组细胞均可在视网膜内存活、迁移,并产生细胞分化,两组细胞均可以分化成胶质细胞、神经元.移植hBDNF-GFP-NSCs组少量细胞分化为节细胞样细胞(Thy1.1+),而GFP-NSCs组未发现有分化为Thy1.1阳性细胞.(2)视网膜铺片Thy1.1免疫荧光染色后计数发现,移植hBDNF-GFP-NSCs的视网膜神经节细胞为(1461±154)个/mm2,明显多于移植GFP-NSCs组(1 244±187)个/mm2(P<0.05).结论 移植后的hBDNF-GFP-NSCs可以分化为神经元和神经胶质细胞,少数可分化为视网膜神经节样细胞.hBDNF-GFP-NSCs移植可以增加RGCs的存活数量,有助于视神经损伤后的修复.%Objective To explore the survival, migration and differentiation of neural stem cells

  3. 用小双链RNA抑制转化入HUVEC中绿色荧光蛋白基因的表达%siRNA suppresses the green fluorescent protein (GFP) gene expression in human umbilical vein endothelial cells

    Institute of Scientific and Technical Information of China (English)

    单志新; 林秋雄; 余细勇; 邓春玉; 郑猛; 谭虹虹; 符永恒; 杨敏; 林曙光

    2006-01-01

    目的:建立稳定表达绿色荧光蛋白(GFP)的人脐静脉血管内皮细胞(HUVECs),研究小干扰RNA(siR-NA)对HUVECs中GFP表达的抑制作用.方法:用lipofectamine2000将编码GFP的质粒pN3-EGFP转入HUVECs中.用G418筛选并维持已转化pN3-EGFP的HUVEC(HUVEC-GFP).利用T7RNA转录试剂盒,制备可抑制GFP基因表达的siRNA(GFPsiRNA)和无关对照的RNA(control siRNA).用oligofectamine将siRNA转入HUVEC-GFP中.继续培养48 h后,检测HUVEC-GFP中GFP蛋白和mRNA表达水平.结果:用G418筛选获得了HUVEC-GFP细胞株,可以观察到GFP的稳定表达.HUVEC-GFP转化siRNA后48 h,GFP的荧光强度明显下降,而对照组的荧光强度无明显下降.半定量RT-PCR检测显示,GFPsiRNA对GFP mRNA表达有较强的抑制作用,抑制率达40%,而control siRNA对GFPmuRNA表达水平无明显的抑制作用.结论:利用体外转录合成的siRNA能有效地抑制HUVECs中GFP的表达.

  4. TALEN/CRISPR-mediated eGFP knock-in add-on at the OCT4 locus does not impact differentiation of human embryonic stem cells towards endoderm.

    Directory of Open Access Journals (Sweden)

    Nicole A J Krentz

    Full Text Available Human embryonic stem cells (hESCs have great promise as a source of unlimited transplantable cells for regenerative medicine. However, current progress on producing the desired cell type for disease treatment has been limited due to an insufficient understanding of the developmental processes that govern their differentiation, as well as a paucity of tools to systematically study differentiation in the lab. In order to overcome these limitations, cell-type reporter hESC lines will be required. Here we outline two strategies using Transcription Activator Like Effector Nucleases (TALENs and Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR-CRISPR-Associated protein (Cas to create OCT4-eGFP knock-in add-on hESC lines. Thirty-one and forty-seven percent of clones were correctly modified using the TALEN and CRISPR-Cas9 systems, respectively. Further analysis of three correctly targeted clones demonstrated that the insertion of eGFP in-frame with OCT4 neither significantly impacted expression from the wild type allele nor did the fusion protein have a dramatically different biological stability. Importantly, the OCT4-eGFP fusion was easily detected using microscopy, flow cytometry and western blotting. The OCT4 reporter lines remained equally competent at producing CXCR4+ definitive endoderm that expressed a panel of endodermal genes. Moreover, the genomic modification did not impact the formation of NKX6.1+/SOX9+ pancreatic progenitor cells following directed differentiation. In conclusion, these findings demonstrate for the first time that CRISPR-Cas9 can be used to modify OCT4 and highlight the feasibility of creating cell-type specific reporter hESC lines utilizing genome-editing tools that facilitate homologous recombination.

  5. Assessing the regulation of leaf redox status under water stress conditions in Arabidopsis thaliana: Col-0 ecotype (wild-type and vtc-2), expressing mitochondrial and cytosolic roGFP1.

    Science.gov (United States)

    Brossa, Ricard; Pintó-Marijuan, Marta; Jiang, Keni; Alegre, Leonor; Feldman, Lewis J

    2013-07-01

    Using Arabidopsis plants Col-0 and vtc2 transformed with a redox sensitive green fluorescent protein, (c-roGFP) and (m-roGFP), we investigated the effects of a progressive water stress and re-watering on the redox status of the cytosol and the mitochondria. Our results establish that water stress affects redox status differently in these two compartments, depending on phenotype and leaf age, furthermore we conclude that ascorbate plays a pivotal role in mediating redox status homeostasis and that Col-0 Arabidopsis subjected to water stress increase the synthesis of ascorbate suggesting that ascorbate may play a role in buffering changes in redox status in the mitochondria and the cytosol, with the presumed buffering capacity of ascorbate being more noticeable in young compared with mature leaves. Re-watering of water-stressed plants was paralleled by a return of both the redox status and ascorbate to the levels of well-watered plants. In contrast to the effects of water stress on ascorbate levels, there were no significant changes in the levels of glutathione, thereby suggesting that the regeneration and increase in ascorbate in water-stressed plants may occur by other processes in addition to the regeneration of ascorbate via the glutathione. Under water stress in vtc2 lines it was observed stronger differences in redox status in relation to leaf age, than due to water stress conditions compared with Col-0 plants. In the vtc2 an increase in DHA was observed in water-stressed plants. Furthermore, this work confirms the accuracy and sensitivity of the roGFP1 biosensor as a reporter for variations in water stress-associated changes in redox potentials.

  6. Non-invasive imaging of GFP-luciferase labeled orthotopic prostate cancer model in nude mice using bioluminescence system%可发光可连续检测原位前列腺癌模型的建立

    Institute of Scientific and Technical Information of China (English)

    宋超; 廖文彪; 杨嗣星; 王玲珑

    2012-01-01

    Objective To develop preclinical orthotopic model in nude mice for sensitive prostate cancer cell tracking during tumor progression using bioluminescent technique.Methods The human prostate cancer cell line PC3 cells were transduced with green fluorescent protein (GFP) -luciferase fusion gene by a lentivirus vector which can express high activity of luciferase and GFP.Stably transduced GFP-LucPC3 monoclonal cells were got with Blasticidin selection.Labeled or normal tumor cells ( 5 × 106 ) were implanted into the flanks of 6 animals to build up an intradermal xenograft prostate cancer model,which provided prostate cancer graft to build the orthotopic prostate tumor model,and to confirm the tumorigenesis ablitiy of GFP-Luc-PC3.Tumor tissue from the either PC3 or GFP-Luc-PC3 line tumors was harvested and cut into pieces of about 2 mm3.These were grafted into the anterior prostates of 24 male animals which were randomly divided into two groups.The tumor growth was monitored by both WIS 200 and ex vivo tumor weight analysis 2,4,6 and 8 weeks after tumor tissue grafting.The bioluminescent signal values as well as tumor weight was measured,and their relationship was analyzed accordingly.Results A GFP-LucPC3 cell line was established which had the same growth pattern as well as tumorigenesis ability as normal PC3 cells.There was a positive linear correlation between bioluminescent signal and cell number with the coefficient factor r =0.997.In orthotopic prostate cancer model,all 12 mice in GFP-Luc-PC3 group developed prostate tumor,from which the bioluminescent signal could be recorded.In normal PC3 group,there was no significant bioluminescent signal.The bioluminescent values (photons/second) in vivo were (69.13298±2.07900) E+05,(82.66208±1.231 00) E+05,(91.94257±2.321 00) E+05 and ( 130.643 40 ± 3.247 00) E + 05 respectively 2,4,6 and 8 weeks after tumor tissue implantation.The tumor weight ex vivo was ( 9.67 ± 1.07 ),( 12.47 ± 2.12),( 16.45 ± 2.57 ),and ( 21

  7. Spread from the Sink to the Patient: In Situ Study Using Green Fluorescent Protein (GFP)-Expressing Escherichia coli To Model Bacterial Dispersion from Hand-Washing Sink-Trap Reservoirs.

    Science.gov (United States)

    Kotay, Shireen; Chai, Weidong; Guilford, William; Barry, Katie; Mathers, Amy J

    2017-04-15

    There have been an increasing number of reports implicating Gammaproteobacteria as often carrying genes of drug resistance from colonized sink traps to vulnerable hospitalized patients. However, the mechanism of transmission from the wastewater of the sink P-trap to patients remains poorly understood. Herein we report the use of a designated hand-washing sink lab gallery to model dispersion of green fluorescent protein (GFP)-expressing Escherichia coli from sink wastewater to the surrounding environment. We found no dispersion of GFP-expressing E. coli directly from the P-trap to the sink basin or surrounding countertop with coincident water flow from a faucet. However, when the GFP-expressing E. coli cells were allowed to mature in the P-trap under conditions similar to those in a hospital environment, a GFP-expressing E. coli-containing putative biofilm extended upward over 7 days to reach the strainer. This subsequently resulted in droplet dispersion to the surrounding areas (dispersion rather than dispersion directly from the P-trap. This work helps to further define the mode of transmission of bacteria from a P-trap reservoir to a vulnerable hospitalized patient.IMPORTANCE Many recent reports demonstrate that sink drain pipes become colonized with highly consequential multidrug-resistant bacteria, which then results in hospital-acquired infections. However, the mechanism of dispersal of bacteria from the sink to patients has not been fully elucidated. Through establishment of a unique sink gallery, this work found that a staged mode of transmission involving biofilm growth from the lower pipe to the sink strainer and subsequent splatter to the bowl and surrounding area occurs rather than splatter directly from the water in the lower pipe. We have also demonstrated that bacterial transmission can occur via connections in wastewater plumbing to neighboring sinks. This work helps to more clearly define the mechanism and risk of transmission from a wastewater

  8. 绿色荧光蛋白基因作为报告基因在水稻基因转化中的应用研究%The Applications of GFP as a Reporter Gene in Rice Genetic Transformation

    Institute of Scientific and Technical Information of China (English)

    程在全; WURAY; 等

    2002-01-01

    本研究中,构建了含有编码绿色荧光蛋白的改进型基因质粒 pJPM5.用基因枪法分别把pJPM5 和另一带有绿色荧光蛋白基因的质粒pSBG700转入水稻TNG67愈伤组织.用Southern杂交法证实了转基因的存在,而且表明多数转基因植株含有1 到8个拷贝的转基因.取2个月的转基因植株上的叶片用于分析绿色荧光蛋白基因表达.用SL M-8000荧光分析仪定量测定绿色荧光蛋白.多数转基因植株具有很高的绿色荧光蛋白信号. 虽然水稻植株有少量自发荧光,但是绿色荧光蛋白基因表达出的绿色荧光蛋白信号比植株的自发荧光强得多,其测定不会受自发荧光的太大影响.在荧光显微镜下观察到了绿色荧光蛋白基因的表达.借助观察分析绿色荧光蛋白基因的瞬时表达,本研究还发现基因枪法转化中 ,如果两枪的气压为900psi & 1350 psi,比两枪的气压都为900psi或者1350psi更好,因其能使质粒进入更多的细胞.研究结果表明,绿色荧光蛋白基因可以作为水稻(甚至小麦、玉米)转基因研究中的报告基因.研究还显示,MAR序列能明显增强绿色荧光蛋白基因的表达能力(这一结果在另文讨论).%In this study,a plasmid pJPM5 containing modified G FP gene which encode the green fluorescent protein (GFP) was constructed.Micropr ojectile bombardment was used to separately introduce two plasmids pJPM5 and pSB G700 into rice TNG67 calli.The transgenic plants were confirmed by Southern blot .Most of the transgenic plants contain 1 to 8 copies of transgene.GFP gene expre ssion was measured in the extracts from rice leaf of two-month-old transgenic plants.And the quantification of gfp expression is carried by the SLM-8000 F luorescence Analyzer. Most of the transgenic plants have showed significant GFP signal. Even though the rice plant has auto-fluorescence, the expression of GFP is high enough to give out much higher fluorescence signal compared with auto

  9. Noninvasive and real-time monitoring of molecular targeting therapy for lymph node and peritoneal metastasis in nude mice bearing xenografts of human colorectal cancer cells tagged with GFP and DsRed

    Science.gov (United States)

    Nakanishi, Hayao; Hara, Masayasu; Ikehara, Yuzuru; Tatematsu, Masae

    2007-02-01

    We have developed an in vivo imaging system consisting of GFP- and DsRed-tagged human colonic cancer cell line, which has peritoneal and lymph node metastatic potential and show high sensitivity to EGFR targeting drugs, and convenient detection devices for GFP and DsRed. The latter includes a small handy fluorescence detection device for external monitoring of the therapeutic effect of the drug and a convenient stereo fluorescent microscope for internal visualization of micrometastases. We applied this imaging system to investigate anti-metastatic effects of EGFR targeting drugs such as gefitinib (Iressa). This system allowed sensitive detection of the development of peritoneal and lymph node metastases from the micrometastasis stage at the cellular level and also permited noninvasive, non-anesthetic monitoring of anti-metastatic effect of the drug in an animal facility without any pretreatment. Significant decreases in the intraabdominal metastatic tumor growth and prevention of inguinal lymph node metastasis by gefitinib treatment could be clearly monitored. These results suggest that convenient, low-cost, true real-time monitoring of therapeutic effect using such a fluorescence-mediated whole body imaging system seems to enhance the speed of preclinical study for novel anti-cancer agents and will allow us to understand the action mechanism of molecular targeting drugs.

  10. Expression of both N- and C-terminal GFP tagged huCD36 and their discrepancy in OxLDL and pRBC binding on CHO cells

    Directory of Open Access Journals (Sweden)

    Crandall Ian

    2007-09-01

    Full Text Available Abstract CD36, an 88 kDa membrane glycoprotein, is found in several cell types and it has been characterized to have two hydrophobic domains at their N- and C-termini which are essential for protein folding and targeting. In this study, we first tagged the green fluorescent protein (GFP to both the N- and C-termini of huCD36 and investigated their cellular expression and influences on lipoprotein and plasmodium falciparium parasitized erythrocytes (pRBC binding. Our work revealed that huCD36 proteins are expressed normally irrespective of the GFP tag presence at either the N- or C-termini. However, the two recombinant proteins showed discrepancy in uptake and surface-binding of OxLDL but they did not affect pRBC binding. These results suggested that the interaction between oxLDL and CD36 could be blocked using recombinant proteins and this may be useful in potential control of the trafficking of modified lipoproteins into monocytes leading to atherogenesis.

  11. Targeting of GFP-Cre to the mouse Cyp11a1 locus both drives cre recombinase expression in steroidogenic cells and permits generation of Cyp11a1 knock out mice.

    Directory of Open Access Journals (Sweden)

    Laura O'Hara

    Full Text Available To permit conditional gene targeting of floxed alleles in steroidogenic cell-types we have generated a transgenic mouse line that expresses Cre Recombinase under the regulation of the endogenous Cytochrome P450 side chain cleavage enzyme (Cyp11a1 promoter. Mice Carrying the Cyp11a1-GC (GFP-Cre allele express Cre Recombinase in fetal adrenal and testis, and adrenal cortex, testicular Leydig cells (and a small proportion of Sertoli cells, theca cells of the ovary, and the hindbrain in postnatal life. Circulating testosterone concentration is unchanged in Cyp11(+/GC males, suggesting steroidogenesis is unaffected by loss of one allele of Cyp11a1, mice are grossly normal, and Cre Recombinase functions to recombine floxed alleles of both a YFP reporter gene and the Androgen Receptor (AR in steroidogenic cells of the testis, ovary, adrenal and hindbrain. Additionally, when bred to homozygosity (Cyp11a1(GC/GC , knock-in of GFP-Cre to the endogenous Cyp11a1 locus results in a novel mouse model lacking endogenous Cyp11a1 (P450-SCC function. This unique dual-purpose model has utility both for those wishing to conditionally target genes within steroidogenic cell types and for studies requiring mice lacking endogenous steroid hormone production.

  12. Cloning and expression of recombinant human β2m-GFP protein containing a pentameric domain%含五聚结构域的重组人β2m-GFP蛋白的构建

    Institute of Scientific and Technical Information of China (English)

    丁洁; 王燕

    2011-01-01

    本研究的目的是为得到表达人MHCⅠ类分子轻链蛋白β2m、β2m的C-末端与一段五聚体(penta)序列相连、且共价结合一段荧光索编码序列(GFP)的五聚重组人β2m-GFP蛋白.采用PCR扩增GFP基因及β2m基因片段,将其克隆到原核表达载体,并通过IPTG诱导目的基因在大肠杆菌中表达融合蛋白.提纯重组蛋白,并用SDS-PAGE和蛋白印迹法鉴定.结果表明,成功将GFP基因或人β2m基因片段插入含五聚结构域的PVT2载体.转化菌经诱导后,SDS-PAGE显示有新生的蛋白表达条带,分子量与预期的大小基本一致.重组蛋白用Ni-NTA柱提纯,纯化蛋白的蛋白质经SDS-PAGE分析可见单一条带.Western blot显示重组蛋白具有良好的免疫活性.因此,我们获得了含五聚结构域的人β2m-GFP在原核系统中的稳定表达,为后续深入研究含五聚结构域的重组MHCⅠ类分子的功能及应用奠定了基础.%The aim of this study is to construct a prokaryotic expression vector for human β2 m-GFP gene containing a pentameric domain and to analyze the characteristics of the expressed fusion protein. The recombinant protein had many characters, such as expression of human β2 m, binding to a pentameric domain and containing GFP acting as the tag to label the protein. Human β2m was obtained through PCR, and then cloned into the vector PVT2 containing a pentameric domain. This recombinant protein was achieved in E. coli through IPTG induction. The expressed product was purified with Ni-NTA column, while the immunological activity of the expressed product was detected by Western blotting. The results showed that the human β2 m gene fragment with length of approximately 300 bp was amplified and cloned into plasmid PVT2. The GFP fragment was also cloned into the plasmid. The purified expressed product reached a high purity in band with a relative molecular weight which was consistent with the expectation. Western blot method showed that the

  13. fos-GFP转基因小鼠学习记忆能力的变化%THE CHANGES OF LEARNING AND MEMORY ABILITY IN fos-GFP TRANSGENIC MICE

    Institute of Scientific and Technical Information of China (English)

    肖克伟; 刘天蔚; 马泽刚; 周宇

    2013-01-01

    目的 研究fos-GFP转基因小鼠学习记忆能力的变化.方法 转基因组和对照组小鼠分别采用高架十字迷宫、旷场实验、水迷宫测试、条件性场景恐惧记忆测试方法进行小鼠的自发活动、焦虑状态及学习记忆能力测试.结果 fos-GFP转基因小鼠与正常小鼠旷场内运动距离、运动速度、在旷场边缘区逗留的时间及在十字迷宫中开放臂探究的时间比较差异无显著性(P>0.05);两组小鼠水迷宫训练中各时间点找到平台的潜伏期比较差异无显著性(P>0.05);两组小鼠水迷宫测试中在各象限时间百分比比较,差异无显著性(P>0.05).fos-GFP转基因小鼠在无特定场景提前接触的条件恐惧测试中的僵立时间与正常小鼠比较差异有显著性(t=9.48,P<0.001).结论 fos-GFP转基因小鼠海马依赖性的联合型学习记忆能力有所提高.%Objective To study the changes of the ability on learning and memory in fos-GFP transgenic mice.Methods The mice in the fos-GFP group and the control were tested by using overhead cross maze,open field,and Morris Water Maze.The spontaneous activity,anxiety state,the ability of learning and memory were tested as well.Results The differences between fos-GFP mice and the controls were not significant in terms of distance of motion within the field,velocity,duration of stay at the marginal zone,and duration of open arm in the maze (P>0.05).The difference between the mice in the two groups was not significant with regard to latency of finding the flat at each time point (P>0.05),and the percentage of duration in target quadrant in Morris Water Maze (P>0.05),and similar freezing time in contextual fear conditioning test (P>0.05).The fos-GFP mice showed higher freezing level than normal controls in no-exposed fear conditioning (t=9.48,P<0.001).Conclusion The ability of hippocampus-dependent associative learning and memory in fos-GFP transgenic mice was somewhat improved.

  14. Transformation and Expression of gfp Gene into Escherich coli K88%动物病原大肠杆菌K88的绿色荧光蛋白基因标记及其稳定性研究

    Institute of Scientific and Technical Information of China (English)

    车建美; 刘波; 蓝江林

    2010-01-01

    成功地将gfp/luxAB双标记基因整合到K88染色体上,得到绿色荧光蛋白基因标记的大肠杆菌K88:gfp/lux,其菌体和菌落形态与原始菌株K88完全一致,引入的新质粒不影响菌株的基本形态.从含gfp基因的质粒DNA和K88:gfp/lux基因组DNA上均可扩增出大小约700 bp的gfp基因片段.大肠杆菌特异性基因检测结果表明,从大肠杆菌K88和K88:gfp/lux基因组DNA上均扩增出大小约260 bp的大肠杆菌特异性基因片段,说明gfp基因标记后的菌株均为大肠杆菌.在相同的培养条件下,K88:gfp/lux和K88的生长曲线的变化趋势基本相同.通过检测肠毒性基因(estA)发现,从大肠杆菌K88和K88:gfp/lux基因组DNA上均扩增出大小约158 bp的肠毒性基因片段,说明gfp基因标记后的菌株在肠毒性方面未发生变化.在无选择压力条件下将K88:gfp/lux菌株每隔12 h连续转接10次后,所有菌落均保持着均匀并且强烈的绿色荧光,说明标记基因在K88:gfp/lux中的表达稳定性很高.K88:gfp/lux和K88在中性偏酸性的环境中生长较好,当初始pH值偏碱性时,生长较差.

  15. 电激转化GFP基因在小麦合子和早期原胚中的高频表达%High Frequency of GFP Gene Transient Expression in Electroporated Zygotes and Early Proembryos of Wheat

    Institute of Scientific and Technical Information of China (English)

    王丽萍; 赵洁

    2003-01-01

    用电激法将GFP基因成功转入分离的小麦(Triticum aestivum L.)合子及早期原胚中.在电场强度150 V/cm、电容25 μF、线性DNA浓度200 μg/mL、电激缓冲液pH 7.2的条件下,得到GFP基因在早期原胚中的高频瞬间表达(46.7%).与开花后5 d胚胎的最适电场强度相比,合子和早期原胚因较幼嫩而最适电场强度较低.电激后的一些早期原胚可以在KM8p培养基中培养并继续分裂,分裂后的细胞中也能观察到GFP基因的表达.此外,电激后的合子及2细胞、4细胞和8细胞原胚中没有看到基因表达的嵌合现象.%Green fluorescent protein (GFP) gene was successfully transferred into the isolated zygotes and early proembryos of wheat (Triticum aestivum L.) by electroporation. A frequency, as high as 46.7% of GFP gene transient expression in early proembryos, was achieved under 150 V/cm electric field strength, 25 μF capacitor, 200 μg/mL of linear plasmid DNA and an electroporation buffer at pH 7.2. Compared with five-day-old proembryos, the zygotes and early proembryos needed lower optimum strength of electric field. After culturing in KM8p medium, the electroporated early proembryos divided and GFP gene expression was observed in daughter cells and subsequent divisions. There was no mosaicism of gene expression in the zygotes and 2-, 4- and 8-celled proembryos.

  16. 溶杆菌SNNU513基因gfp标记及在玉米根部定殖%Colonization of gfp-tagged Lysobacter sp. SNNU513 on Maize’s Root

    Institute of Scientific and Technical Information of China (English)

    武坤毅; 王斐斐; 崔浪军; 章华伟; 白成科

    2014-01-01

    Lysobacter sp. SNNU513 isolated from Radix polygalae rhizospher could inhibit pathogenic fungus. In this study, the preparation of the efficient competent cells were screened out and pGLO plasmid was introduced into the competent cells by electroporation and transformation. The results showed that the recombinant strain SNNU513-pGLO could efficiently and stably express the green fluorescent protein gene (gfp) when the electric field strength was 20 kV/cm and the electric pulse time was 5 ms. The percent of the green cells was 100%when the strain SNNU513-pGLO was recirculated in the non-selective medium for 20 times. Both strains SNNU513-pGLO and SNNU513 showed the same growth characteristics and the same inhibition of Rhizotonia cerealis in vivo. The gene gfp was transferred into original strain Lysobacter sp. SNNU513 by electroporation successfully. The gfp-tagged strain adhering more tightly to the velamen than the phloem could colonize on the surface and interior of maize’s root.%溶杆菌属细菌在植物病害生物防治中有着广阔的应用潜力。本文以本实验室从中药材远志分离筛选的溶杆菌属新菌株Lysobacter sp. SNNU513为材料,筛选出高效制备该菌株感受态细胞Inoue法,电击转化条件为场强20 kV/cm、电脉冲时间5 ms时可将含绿色荧光蛋白基因gfp的质粒pGLO导入该菌株感受态细胞中,重组菌SNNU513-pGLO能高效、稳定表达绿色荧光蛋白基因,与出发菌株的生长特性、抑菌活性等生物学特性差异不显著。将成功构建的重组菌SNNU513-pGLO用于检测该菌株在玉米根部的定殖规律,结果表明,定殖量从表皮到韧皮部有明显减少趋势。

  17. Study on A GFP Expression System for Detecting Estrogenic Compounds%利用GFP表达系统检测雌激素类化合物的研究

    Institute of Scientific and Technical Information of China (English)

    雷卫祺; 马海蓉; 孙怡; 曹旭

    2006-01-01

    根据雌激素类化合物的转录调节原理,构建受雌激素应答元件(ERE)调控的3×EREEGFP-N1重组报告基因载体,转染雌激素受体阳性的MCF-7乳腺癌细胞,分离出稳定转染的细胞克隆ERE-GFP-MCF7,将不同浓度的雌二醇(E2)及其他化合物加入稳定转染的细胞后检测GFP表达水平的变化.雌二醇(E2)以剂量依赖的方式诱导稳定转染细胞ERE-GFP-MCF7表达GFP,最大效应浓度为1×10-10mol/L,EC50为1.5×10-11mol/L;已知的植物雌激素大豆甙元和白藜芦醇同样以剂量依赖的方式诱导GFP的表达,EC50分别为2.4×10-7mol/L和6.2×10-6mol/L,而葡萄籽多酚没有明显的雌激素样活性.雌激素拮抗剂他莫西芬以剂量依赖的方式抑制雌二醇诱导GFP的表达,最大抑制浓度为1×10-7mol/L.利用此细胞模型检测不同化合物诱导的GFP表达强度可快速检测雌激素受体的配体.

  18. Biological features of human mesenchymal stem cells and labelling with Ad-GFP transfection%人骨髓间充质干细胞生物学特性及腺病毒介导的GFP标记

    Institute of Scientific and Technical Information of China (English)

    谭云鹤; 种铁; 杨平; 郭子宽; 甘为民; 陈长虹; 翟宇强; 石硕文; 彭秀君

    2012-01-01

    Objective To establish a method for isolating, culturing and identifying human mesenchymal stem cells (hMSCs) so as to investigate the transient expression by using Ad-GFP transfection. Methods hMSCs were isolated and purified from human bone marrow with Ficoll density gradient centrifugation and by adhering to the culture plastic. The proliferation ability was evaluated by MTT assay. ALP Kit and red oil O staining were used to prove the differentiation ability of osteoblasts and adipoblasts, respectively. The potential to differentiate into smooth muscle cells (SMCs) was assayed with α-SMA monoclonal antibody. Surface markers in hMSCs were detected by flow cytometry (FCM). Then Ad-GFP was transfected into hMSCs and the transient expression was examined with fluorescence microscope and FCM. Results hMSCs were fibroblast-like in morphology with a high proliferation, and homogenously expressed CD44, CD73, CD106 and PDGFRP were negative for CD14, CD31, and CD45. After induction, the cells were ALP and a-SMA positive and red oil O staining was positive, too. At 48-h culture, the transient expression was up to 99.81% when transfected at an MO! of 200. Conclusion Highly purified hMSCs can be obtained with Ficoll density gradient centrifugation. Ad-GFP is a preferable method to label cells and can be used as a source for tissue engineering in vivo.%目的 建立人骨髓间充质干细胞(hMSCs)分离、培养以及鉴定的方法,同时应用腺病毒介导的绿色荧光蛋白(Ad-GFP)检测细胞转染的效率.方法 应用人淋巴细胞分离液(Ficoll)对hMSCs进行分离,经贴壁纯化后用MTT法检测增殖能力;并对其成骨、成脂、成平滑肌诱导分别进行碱性磷酸酶(ALP)、油红O染色及α-SMA免疫细胞化学检测;采用流式细胞仪(FCM)检测细胞表面标志的表达.用Ad-GFP转染,并应用荧光显微镜与FCM检测转染效率.结果 hMSCs镜下为成纤维样形态,约在第4天进入对数增长

  19. EFEKTIVITAS PROMOTER b-ACTIN IKAN MEDAKA (Oryzias latipes DENGAN PENANDA GEN hrGFP (HUMANIZED Renilla reniformis GREEN FLUORESCENT PROTEIN PADA IKAN LELE (Clarias gariepinus KETURUNAN F0

    Directory of Open Access Journals (Sweden)

    Muhammad Hunaina Fariduddin Ath-thar

    2016-11-01

    Full Text Available Promoter merupakan salah satu faktor penentu dalam teknologi transgenesis. Pada penelitian ini efektivitas promoter b-actin ikan medaka diuji pada telur ikan lele fase 1 sel dan 2 sel. Penelitian dilakukan di Laboratorium Pengembangbiakan dan Genetika Ikan, Fakultas Perikanan dan Ilmu Kelautan, Institut Pertanian Bogor. Penelitian ini berlangsung selama 3 bulan. Insersi promoter dilakukan dengan cara menginjeksi telur hasil pemijahan buatan dengan plasmid DNA pmb-actin–hrGFP pada fase telur 1 sel dan 2 sel. Konsentrasi DNA yang digunakan adalah 20 µg/mL. Perkembangan embrio diamati pada 8, 12, 16, 20, 24 jam setelah gen disuntikkan serta 4 dan 8 jam setelah telur menetas. Derajat sintasan embrio (DKH, derajat penetasan (DP, dan persentase embrio mengekspresikan transgen (PEMT dicatat selama pengamatan. Hasil yang diperoleh menunjukkan bahwa promoter b-actin ikan medaka aktif pada ikan lele, dengan adanya ekspresi gen hrGFP pada embrio setelah 8, 12, 16, 20, 24 jam setelah penyuntikan serta 4 dan 8 jam setelah telur menetas. Nilai DKHkontrol pada jam ke-24 adalah 97,1% dan untuk DKHinjeksi pada jam ke-24 adalah 85,7%. Untuk PEMT pada telur yang disuntik pada fase 1 sel mempunyai persentase yang lebih tinggi (66,7% dibanding telur yang disuntik pada fase 2 sel (50,0%. Derajat penetasan memperlihatkan bahwa jumlah telur untuk penyuntikan pada fase 1 sel lebih tinggi (93,3% dibanding dengan yang disuntik pada fase 2 sel (55,0%. Total jumlah telur yang berhasil disuntik adalah 35 butir dan yang terekspresi sebanyak 20 butir (57,1%. Promoter is one of the most important factors in transgenic. In this study, effectiveness of b-actine of medaka (Oryzias latipes was examined in the eggs of walking catfish at the first cleavage and two cell stage. The experiment was carried out in the Laboratory of Fish Genetic, Fac. of Fisheries, Bogor Agricultural University for three months. Promoter was inserted by injecting artificial fertilization eggs with DNA

  20. Construction and identification of recombinant adenovirus shuttle plasimid expressing FLAG labeled BMP2 and traced by GFP%GFP示踪FLAG抗原表位标记BMP2转基因腺病毒穿梭质粒的构建

    Institute of Scientific and Technical Information of China (English)

    张正; 李谌; 陈峻江; 刘丹平

    2011-01-01

    Objective To construct a novel recombinant adenovirus shuttle plasimid expressing the BMP2 fused to FLAG epitope and green fluorescent protein(GFP) as a tracer protein of the recombinant adenovirus on the same transcript.Methods The base pairs behind the translation stop codon TAG were removed and a Xho I restriction site was added following the 3'end of the mutant through PCR. After being tested through sequencing , the mutant of BMP2 gene ( BMP2+ gene)was ligated into the multiple cloning sites of the adenovirus shuttle plasmid pShuttle CMV-IRES-hrGFP-1 by the directional cloning method. The analysis of restricion map was adopted to identify the correct recombinants to monitor the expression of BMP2 and GFP in the MSCs and the HEK293A, the recombinants were transfected, fluorescence microscope and immunol histochemistry were employed. Rsults The plasimid (pShutfle CMV-BMP2 + -IRES-hrGFP-1 ) was centrcted correctly by two kinds of rectriction endnoucleases and sequence of the recombinant. The GFP and BMP2 were expressed in HEK293A and MSCs. Conclusion The adenovirus shuttle plasmid pShuttle CMV-BMP2+-IRES-hrGFP-1 is constructed successfully.%目的 构建同时表达具有抗原表位FLAG标记的重组人骨形态发生蛋白2(rhBMP2)目的蛋白和示踪绿色荧光蛋白(GFP)报告分子的腺病毒穿梭质粒pShuttle CMV-BMP2+-IRES-hrGFP-1.方法 采用PCR技术对pcDNA3-BMP2携带的BMP2基因诱变,去除翻译终止密码子后的基因序列并添加新的酶切识别位点XhoⅠ.测序检测诱变情况,将诱变后的BMP2基因定向导入pShuttle CMV-IRES-hrGFP-1,将质粒分别转染人胚肾细胞HEK293A和兔骨髓间充质干细胞(MSCs).通过限制性内切酶酶切图谱分析该质粒;采用荧光显微镜检查和免疫组化SP法测定HEK293A中的GFP和MSCs中的BMP2,行重组腺病毒穿梭质粒鉴定.结果 质粒pShuttle CMV-BMP2+-IRES-hrGFP-1经双酶切鉴定图谱分析构建正确,HEK293A、MSCs中均有GFP和BMP2表达.结论 p

  1. hBDNF-GFP基因转染神经干细胞对视神经损伤大鼠视网膜BDNF表达的影响%Effects of hBDNF-GFP gene-transfected neural stem cell transplantation on BDNF expression in the retina of rats following optic nerve crush injury

    Institute of Scientific and Technical Information of China (English)

    刘勇; 陈二涛; 冯东福; 潘栋超; 汪洋

    2009-01-01

    目的 探讨移植hBDNF-GFP基因转染神经干细胞后对视神经损伤大鼠视网膜BDNF表达的影响.方法 ①78只SD大鼠随机分为正常对照组(n=6)、视神经夹伤组(n=72).视神经夹伤组动物行右侧视神经夹伤后随机平均分为三个亚组:分别于玻璃体腔内注射0.01 mol/L PBS(PBS组),GFP基因转染神经干细胞(GFP-NSCs组)和hBDNF-GFP基因转染神经干细胞(hBDNF-GFP-NSCs组).各组动物单纯暴露左侧视神经作为假损伤组.分别于移植后3 d,7 d,14 d和28 d处死动物取视网膜,ELISA法检测各组视网膜中BDNF含量.②另取6只视神经损伤大鼠移植hBDNF-GFP-NSCs,分别于2周、4周和8周各处死2只大鼠,取眼球做冰冻切片观察移植细胞存活、迁移情况.③35只sD大鼠随机分为4组:正常对照组(n=5)、右眼视神经损伤NSCs治疗组(n=10)、GFP-NSCs治疗组(n=10)及hBDNF-GFP-NSCs治疗组(n=10).④各组于术后4周和8周分别处死5只大鼠,West-era-blot法检测视网膜组织中BDNF表达.结果 ①ELISA结果显示,正常对照组BDNF含量与假损伤组间比较差异无统计学意义(P>0.05),移植手术后第3天时,三个损伤亚组视网膜匀浆上清中hBDNF含量明显增加(与假损伤组比较P0.05);7 d时,GFP-NSCs组与假损伤组比较差异具有统计学意义(P0.05),PBS组与GFP-NSCs组间及hBDNF-GFP-NSCs组与GFP-NSCs组间差异具有统计学意义(P0.05). Three days after NSC transplantation, BDNF expression increased significantly in the three injured sub-groups compared with the sham-injury group, (P 0.05). Seven days after transplantation, there was a significant difference in BDNF expression between the GFP-NSC group and the sham-injury groups (P 0.05). Fourteen and 28 days after transplantation, BDNF expressions decreased in the PBS group and the GFP-NSC groups, while BDNF expressions in the hBDNF-GFP-NSC group increased significant-ly compared with the other three groups (P < 0.05); ②Frozen section showed that

  2. The effect of MEP pathway and other inhibitors on the intracellular localization of a plasma membrane-targeted, isoprenylable GFP reporter protein in tobacco BY-2 cells [v2; ref status: indexed, http://f1000r.es/2af

    Directory of Open Access Journals (Sweden)

    Michael Hartmann

    2013-11-01

    Full Text Available We have established an in vivo visualization system for the geranylgeranylation of proteins in a stably transformed tobacco BY-2 cell line, based on the expression of a dexamethasone-inducible GFP fused to the carboxy-terminal basic domain of the rice calmodulin CaM61, which naturally bears a CaaL geranylgeranylation motif (GFP-BD-CVIL. By using pathway-specific inhibitors it was demonstrated that inhibition of the methylerythritol phosphate (MEP pathway with known inhibitors like oxoclomazone and fosmidomycin, as well as inhibition of the protein geranylgeranyltransferase type 1 (PGGT-1, shifted the localization of the GFP-BD-CVIL protein from the membrane to the nucleus. In contrast, the inhibition of the mevalonate (MVA pathway with mevinolin did not affect the localization. During the present work, this test system has been used to examine the effect of newly designed inhibitors of the MEP pathway and inhibitors of sterol biosynthesis such as squalestatin, terbinafine and Ro48-8071. In addition, we also studied the impact of different post-prenylation inhibitors or those suspected to affect the transport of proteins to the plasma membrane on the localization of the geranylgeranylable fusion protein GFP-BD-CVIL.

  3. Efficiency of Iepsilon promoter-directed switch recombination in GFP expression-based switch constructs works synergistically with other promoter and/or enhancer elements but is not tightly linked to the strength of transcription.

    Science.gov (United States)

    Zhang, Ke; Zhang, Ling; Yamada, Takechiyo; Vu, Michael; Lee, Anna; Saxon, Andrew

    2002-02-01

    One key unresolved issue in immunoglobulin class switch recombination (CSR) is how the accessibility of the switch region for CSR is controlled. To better understand the nature of accessibility control for human Ig CSR, we developed a novel inducible switch recombination assay based on expression of green fluorescence protein (GFP) from switch constructs undergoing substrate switch recombination (SSR). Efficient SSR depends on the cytokine-inducible Iepsilon promoter and co-stimulation with IL-4+anti-CD40. Characterization of SSR reveals that both S-S deletional recombination and S-S inversion occur. We show that the IL-4-inducible Iepsilon promoter (pIepsilon) selectively determines the efficiency of the accessibility for SSR. However, the pIepsilon-induced transcription, by itself,is not sufficient to direct efficient SSR. For efficient SSR, both pIepsilon-driven transcriptional activity and an additional promoter/enhancer-derived activity are required. The efficiency of SSR is not tightly correlated with the strength of the combined transcriptional activity. Our results suggest that the mechanism(s) underlying the transcriptional activity, e.g. DNA modification is important for controlling the accessibility for efficient switch recombination.

  4. Quantitative Analysis of Human T-Lymphotropic Virus Type 1 (HTLV-1) Infection Using Co-Culture with Jurkat LTR-Luciferase or Jurkat LTR-GFP Reporter Cells.

    Science.gov (United States)

    Alais, Sandrine; Dutartre, Hélène; Mahieux, Renaud

    2017-01-01

    Unlike HIV-1, HTLV-1 viral transmission requires cell-to-cell contacts, while cell-free virions are poorly infectious and almost absent from body fluids. Though the virus uses three nonexclusive mechanisms to infect new target cells: (1) MTOC polarization followed by formation of a virological synapse and viral transfer into a synaptic cleft, (2) genesis of a viral biofilm and its transfer of embedded viruses, or (3) HTLV-1 transmission using conduits. The Tax transactivator and the p8 viral proteins are involved in virological synapse and nanotube formation respectively.HTLV-1 transcription from the viral promoter (i.e., LTR) requires the Tax protein that is absent from the viral particle and is expressed after productive infection. The present chapter focuses on a series of protocols used to quantify HTLV-1 de novo infection of target cells. These techniques do not discriminate between the different modes of transmission, but allow an accurate measure of productive infection. We used cell lines that are stably transfected with LTR-GFP or LTR-luciferase plasmids and quantified Green Fluorescent Protein expression or luciferase activity, since both of them reflect Tax expression.

  5. 绿色荧光蛋白在胚胎干细胞研究中的应用%Applications of Green Fluorescent Protein(GFP) in the Research of Embryonic Stem Cells

    Institute of Scientific and Technical Information of China (English)

    杨玉艾; 华进联; 窦忠英

    2004-01-01

    绿色荧光蛋白(green fluorescent protein,GFP)作为一种方便、有效的活性标记物,无需外源反应底物,无需进行细胞或组织的固定和渗透处理,使检测更加方便.是细胞生物学和分子生物学研究的一个重要工具,已得到了广泛的应用.胚胎干细胞(Embryonic Stem Cell,ES cell)是从早期胚胎中分离得到的多能细胞,在胚胎发育、细胞移植、组织器官构建、药物研制、基因治疗等研究方面发挥着巨大的作用.本文就GFP的特性及其在ES细胞研究中的应用作一简述.

  6. siRNA抑制外源绿色荧光蛋白在neuro-2a细胞株中的表达%siRNAs interference exogenous GFP gene expression in neuro-2a cells

    Institute of Scientific and Technical Information of China (English)

    张小勤; 李峰; 赵艳; 彭映基; 潘玉春; 孟和; 崔芳岩

    2007-01-01

    目的:用RNAi技术抑制哺乳动物神经元中外源报告基因的表达,并探讨该过程中RNAi的时间及剂量效应,为利用RNAi技术研究神经元基因功能提供参考.方法:采用神经细胞来源的细胞系neuro-2a小鼠神经瘤细胞为模型,将外源绿色荧光蛋白(GFP)基因转染到neuro-2a细胞内,利用体外转录法合成siRNA,分为3个剂量组对其进行干扰.结果:Neuro-2a细胞可以被有效地转染,而且siRNA在neuro-2a细胞内可以有效发挥干扰作用.这种干扰作用呈现出一定的剂量效应.结论:RNAi技术可以成功用于neuro-2a细胞抑制基因的表达,这种对GFP表达规律及RNAi剂量效应的研究为利用RNAi技术研究神经元基因功能提供了一定的理论参考和依据.

  7. Integration and expression of GFP gene directed by the erythroid-specific element in transgenic mice%红系特异的GFP基因在转基因小鼠中的整合和表达

    Institute of Scientific and Technical Information of China (English)

    颜景斌; 肖艳萍; 陈美珏; 黄淑帧; 曾溢滔

    2004-01-01

    应用荧光定量PCR技术对由位点控制区LCR的HS2元件和β-珠蛋白基因启动子指导的红系特异表达绿色荧光蛋白(GFP)基因的转基因小鼠中外源基因拷贝数进行测定,使用荧光显微镜和流式细胞仪检测小鼠外周血中GFP的表达水平,并运用荧光原位杂交技术(FISH)确定了其中两只转基因小鼠中外源基因的整合位点,结果表明:在转基因小鼠中外源基因的拷贝数各不相同且相差较大,而且拷贝数与GFP基因的表达量之间未呈现出相关性;FISH分析确定出两只转基因小鼠的外源基因整合于不同的染色体上;杂交信号的强弱与拷贝数的多少相一致[动物学报50(2):263-268,2004].

  8. Improving the production of transgenic fish germlines: in vivo evaluation of mosaicism in zebrafish (Danio rerio using a green fluorescent protein (GFP and growth hormone cDNA transgene co-injection strategy

    Directory of Open Access Journals (Sweden)

    Márcio de Azevedo Figueiredo

    2007-01-01

    Full Text Available In fish, microinjection is the method most frequently used for gene transfer. However, due to delayed transgene integration this technique almost invariably produces mosaic individuals and if the gene is not integrated into germ cells its transmission to descendants is difficult or impossible. We evaluated the degree of in vivo mosaicism using a strategy where a reporter transgene is co-injected with a transgene of interest so that potential germline founders can be easily identified. Transgenic zebrafish (Danio rerio were produced using two transgenes, both comprised of the carp beta-actin promoter driving the expression of either the green fluorescent protein (GFP reporter gene or the growth hormone cDNA from the marine silverside fish Odonthestes argentinensis. The methodology applied allowed a rapid identification of G0 transgenic fish and also detected which fish were transmitting transgenes to the next generation. This strategy also allowed inferences to be made about genomic transgene integration events in the six lineages produced and allowed the identification of one lineage transmitting both transgenes linked on the same chromosome. These results represent a significant advance in the reduction of the effort invested in producing a stable genetically modified fish lineage.

  9. Colonization of Potato Rhizosphere by GFP-Tagged Bacillus subtilis MB73/2, Pseudomonas sp. P482 and Ochrobactrum sp. A44 Shown on Large Sections of Roots Using Enrichment Sample Preparation and Confocal Laser Scanning Microscopy

    Directory of Open Access Journals (Sweden)

    Sylwia Jafra

    2012-12-01

    Full Text Available The ability to colonize the host plants’ rhizospheres is a crucial feature to study in the case of Plant Growth Promoting Rhizobacteria (PGPRs with potential agricultural applications. In this work, we have created GFP-tagged derivatives of three candidate PGPRs: Bacillus subtilis MB73/2, Pseudomonas sp. P482 and Ochrobactrum sp. A44. The presence of these strains in the rhizosphere of soil-grown potato (Solanum tuberosum L. was detected with a classical fluorescence microscope and a confocal laser scanning microscope (CLSM. In this work, we have used a broad-field-of-view CLMS device, dedicated to in vivo analysis of macroscopic objects, equipped with an automated optical zoom system and tunable excitation and detection spectra. We show that features of this type of CLSM microscopes make them particularly well suited to study root colonization by microorganisms. To facilitate the detection of small and scattered bacterial populations, we have developed a fast and user-friendly enrichment method for root sample preparation. The described method, thanks to the in situ formation of mini-colonies, enables visualization of bacterial colonization sites on large root fragments. This approach can be easily modified to study colonization patterns of other fluorescently tagged strains. Additionally, dilution plating of the root extracts was performed to estimate the cell number of MB73/2, P482 and A44 in the rhizosphere of the inoculated plants.

  10. GFP与水稻条纹病毒病害特异蛋白的融合基因在sf9昆虫细胞中的表达%Expression of fusionprotein of GFP and Rice stripe virus disease-specific protein in insect cells sf9

    Institute of Scientific and Technical Information of China (English)

    林董; 郑璐平; 谢荔岩; 吴祖建; 林奇英; 谢联辉

    2008-01-01

    用重叠延伸PCR(overlap Polymerase Chain Reaction,overlap-PCR)方法获得了含有绿色荧光蛋白(Green fluores-cence protein,GFP)和水稻条纹病毒(Rice stripe virus,RSV)病害特异性蛋白SP(Disease-specific protein)两者的融合基因(GFP-SP),并将其克隆至载体pMD18-T,得到的重组质粒pMD18-T-GFP-SP经Xba Ⅰ/Hind Ⅲ双酶切后与经相同方法处理过的杆状病毒转移载体pFastBacHTb相连接构建成重组转移质粒pFastBacHTb-GFP-P.酶切和测序鉴定证明了其序列的正确性并且无移码现象发生.将此质粒转化人含穿梭载体Bacmid的感受态细胞DHIOBac,得到含有目的基因片段的重组杆状病毒穿梭质粒rb-GFP-SP.以之转染草地贪夜蛾(Spodoptera frugiperda,st9)细胞,24~48 h后在显微镜200倍可见光视野下观察到被感染细胞发生了细胞和细胞核变大、细胞内颗粒物增多、细胞脱落甚至裂解等一系列与正常的sf9昆虫细胞形态有明显区别的变化.荧光显微镜下可见部分细胞发出清晰的绿色荧光,且大部分荧光集中在细胞质部分.这些结果表明,GFP-SP融合蛋白在sf9昆虫细胞内成功表达.

  11. Localization of Two GFP-tagged Tobacco Plastid DivisionProtein NtFtsZs in Escherichia coli%烟草质体分裂蛋白NtFtsZs在大肠杆菌中的定位分析

    Institute of Scientific and Technical Information of China (English)

    王东; 孔冬冬; 鞠传丽; 胡勇; 何奕昆; 孙敬三

    2002-01-01

    Two plastid division genes, NtFtsZ1 and NtFtsZ2 isolated from Nicotiana tabacum L. were fused with gfp and expressed in Escherichia coli filamentous bacteria indicated that the NtFtsZs could recognize the potential division sites in E. coli and be polymerized with heterogeneous division of host strain cells and resulted in the long filamentous bacterial morphology. These results suggested that eukaryotic ftsZs have similar function to their prokaryotic homologs. Meanwhile, the different deletions of motifs of NtFtsZs are also employed to investigate the functions of these proteins in E. coli . The results showed that the C-terminal domains of NtFtsZs were related to the correct localization of NtFtsZs in E. coli and the N-terminal domains of NtFtsZs were responsible for the polymerization of homogeneous and heterogeneous FtsZ proteins. The significance of these results in understanding the functions of NtFtsZs in plastid division were discussed.%分别构建了两个烟草(Nicotiana tabacum L.)质体分裂基因NtFtsZ1和NtFtsZ2与编码绿色荧光蛋白的gfpS65A、V68L、S72A基因相融合的原核表达载体,并导入大肠杆菌( Escherichia coli ) JM109菌株中进行表达.全长NtFtsZs∶GFP融合蛋白在菌体中有规律地定位,暗示NtFtsZs能识别大肠杆菌潜在的分裂位点,并能与大肠杆菌的内源FtsZ发生聚合作用;融合蛋白的诱导表达抑制了宿主菌的分裂,形成了明显的丝状菌体,证明真核生物的 ftsZ 基因与大肠杆菌的 ftsZ 基因有相似的作用.同时构建了NtFtsZs不同缺失的原核表达载体,对这两个基因所编码蛋白不同结构域的功能做了初步分析.实验结果表明,烟草FtsZ蛋白的C端结构域与其在大肠杆菌细胞中的正确定位有关;而N端结构域与NtFtsZs∶GFP融合蛋白的聚合有关.

  12. Ex vivo, microelectrode analysis of conduction through the AV node of wild-type and Nkx2-5 mutant mouse hearts as guided by a Cx40-eGFP transgenic reporter.

    Science.gov (United States)

    Gazit, Avihu Z; Li, Alex; Choi, Jacob S; Miquerol, Lucile; Jay, Patrick Y

    2014-01-01

    Abstract Mutations of the cardiac transcription factor NKX2-5 cause hypoplastic development of the AV node and conduction block. How the anatomy of the mutant AV node relates to its function is unknown. We thus studied conduction through the AV nodal region in ex vivo preparations of wild-type and Nkx2-5(+/-) mouse hearts in which the central conduction system was highlighted by a transgenic Cx40-eGFP reporter. Fluorescence imaging guided electrode placement and pacing of the inferior and superior approaches to the AV node. Nkx2-5(+/-) hearts had a prolonged atrio-His interval compared to the wild type, consistent with previous in vivo observations. The conduction time to the His bundle from the Cx40(-) AV nodal region that is superior to and immediately adjacent to the Cx40(+) lower node is slightly, but not significantly greater in Nkx2-5(+/-) than wild-type hearts. A novel phenotype was also observed. Pacing the Cx40(-) inferior approach to the AV node with increasing stimulus strength led to progressive shortening of the stimulus-to-His conduction interval in wild-type but not Nkx2-5(+/-) hearts. The strength of pacing at the Cx40(-) superior approach had no effect on the conduction interval in either group. The prolonged AV delay in the Nkx2-5(+/-) heart appears to arise before the Cx40(+) lower node. Whether the pacing phenotype explains the mutant's conduction defect is uncertain, but the observation adds to a number of unique properties of the inferior approach to the AV node.

  13. APLIKASI MUTAN BERFLUORESENS UNTUK MEMPELAJARI KETAHANAN HIDUP, KOLONISASI DAN PENETRASI ISOLAT Cronobacter sakazakii SELAMA PENGERINGAN JAGUNG [Use of GFP Mutant to Study the Survival, Colonization and Penetration of Cronobacter sakazakii Isolates During Maize Drying

    Directory of Open Access Journals (Sweden)

    Siti Nurjanah*

    2013-12-01

    Full Text Available Cronobacter sakazakii is a Gram-negative emerging pathogen regarded as causative agent of meningitis and necrotizing enterocolitis in certain groups of infants. In the previous research, thirty-two local isolates of C. sakazakii were obtained from various dried food products such as from corn starch, suggesting that they are able to survive drying. Some of the isolates were toxic. Green Fluorescent Protein (GFP have been inserted to C. sakazakii and used as a marker for selective enumeration due to the ability of this protein to fluoresce under UV and to tolerate in ampicillin containing media. The objective of this study was to evaluate the survival, colonization and penetration of two isolates of C. sakazakii from dried food product during maize drying. The maize was challenged with mutants at a concentration of 105-106 CFU/g before drying. Maize drying was performed at temperature of 40, 45 and 50ºC for 4, 6 and 8 days until the moisture content reached 14%. The totals of resistant drying mutants were counted every day onto ampicillin containing media by observing under UV light. The survival rate of C. sakazakii during drying was determined by the slope of linier regression from C. sakazakii survival curve. Isolates of FWHd16, the toxic strain of C. sakazakii, were more resistant to heat treatments in comparison to isolates of YRt2a, or the non toxic strain of C. sakazakii. Following fluorescence and scanning electron microscope observation, it is concluded that both isolates were colonizing on maize surface. These mutants were able to penetrate to the inner side of the grain by entering injured surface or pores at the tip cap of maize.

  14. Construction and Transfection of Sheep Myostatin Expression Vector pAcGFP-MSTN in Sheep Fibroblasts%绵羊Myostatin基因真核表达载体的构建及在其原代成纤维细胞中的瞬时表达

    Institute of Scientific and Technical Information of China (English)

    陆健; 杜立新; 宋正海; 吕延飞; 赵福平; 张莉; 魏彩虹; 范广习; 丁家桐; 李碧春

    2012-01-01

    Myostatin(MSTN)基因是胚胎期肌肉形成和出生后骨骼肌生长的主要调控因子之一,通过抑制肌细胞的扩增和分化而调控肌肉的生长和发育.为了进一步揭示MSTN在绵羊成纤维细胞中的生物学功能,采用RT-PCR从绵羊肌肉组织中扩增MSTN基因,将其cDNA终止密码子TGA删除,采用定向克隆技术连接到带有水母绿色荧光蛋白(AcGFP)报告基因的真核表达载体pAcGFP-N1中,构建融合蛋白重组质粒,经Xho Ⅰ/SacⅡ双酶切、测序鉴定后,用脂质体介导质粒转染绵羊原代成纤维细胞,观测荧光表达及用RT-PCR和Western blotting方法检测基因转录、蛋白质表达情况.结果表明,成功克隆绵羊MSTN基因,通过PCR方法在MSTN阅读框两端引入了XhoⅠ和SacⅡ克隆位点,成功构建pAcGFP-MSTN融合蛋白真核表达载体,重组质粒转染绵羊成纤维细胞24 h后在荧光显微镜下观察到绿色荧光,通过RT-PCR扩增出1138 bp的转录产物,并用Western blotting检测到78 ku目的蛋白的表达.本试验为研究MSTN基因在成纤维细胞和脂肪分化调控中的具体机制奠定基础.%Myostatin(MSTN), an important regulator of embryonic myogenesis and adult skeletal muscle growth, regulated the muscle development by controlling the proliferation and differentiation of myoblast. To explore the biological function of MSTN in sheep fibroblasts, we had amplified the MSTN gene from sheep skeletal muscle by reverse transcription PCR (RT-PCR), deleted the stop codons TGA and cloned into the eukaryotic expression vector pAcGFP-N1 by directional clone. So, the fusion protein recombinant plasmid pAcGFP-MSTN had been constructed. After the restriction enzyme digestion of Xho I /SacⅡ and sequencing, the plasmid had been transfected into the sheep fibroblasts by lipofectamine. We also observed the fluorescence expression under the microscope, examined the transcription and translation of the expression vector pAcGFP-MSTN by RT-PCR and

  15. Root and Leaf Infection as Revealed by Autofluorescent Reporter Protein GFP Labeled Bipolaris sorokiniana in Wheat%利用绿色荧光蛋白报告基因标记研究麦根腐平脐孺孢对小麦根和叶片的侵染

    Institute of Scientific and Technical Information of China (English)

    闫立敏; 王晓鸣; 徐荣旗; 东方阳; 李洪杰

    2012-01-01

    [Objective] The objective of this study is to label Bipolaris sorokiniana, which is the causal agent of common root rot and leaf spot blotch of wheat (Triticum aestivum L.), with green fluorescent protein (GFP) for studying infection of B. sorokiniana on wheat roots and leaves, and to establish a direct and non-destructive method for in vivo observing interaction between pathogen and host plant. [Method] Gene gfp was transferred into B. sorokiniana strain Bs-1 via Agrobacterium tumefaciens-mediated transformation (ATMT). Based on analysis of fluorescence expression, PCR verification, genetic stability, growth parameters, and metabolism of extra cellular enzymes, a transformed strain Bs-GFP that resembled its wild-type strain, was chosen to investigate infection of B. sorokiniana on roots and leaves of wheat cultivar Aikang 58. [Result] Bright green fluorescence was observed in hyphae and conidia of the transformant Bs-GFP. The amplification of the diagnostic bands with the gene-specific markers indicated that gfp was integrated into the genome of B. sorokiniana. Analysis of genetic stability and growth parameters demonstrated that gfp was inherited normally, and the growth rate and metabolism of extracellular enzymes were comparable to the wild type strain. The GFP-labeled strain Bs-GFP was able to incite symptoms on both underground and upperground parts of wheat plants, and the quantities of colonization (in terms of colony forming unit) in roots and basal stem tissues of wheat plants by Bs-GFP was similar as those by Bs-1. [Conclusion]The B. sorokiniana strain expressing GFP obtained via ATMT can be used to directly monitor infection and colonization of the fungus on wheat. The results from this study will facilitate better understanding of the interactions between B. sorokiniana and wheat, as well other cereal crops.%[目的]利用绿色荧光蛋白标记研究麦根腐平脐孺孢(Bipolaris sorokiniana,引起小麦根腐病和叶枯病)对小麦根系和叶

  16. The Study of the Targeting Selectivity and Binding the Surface of Breast Cancer Cells with the Fusion Protein Anti-HER2-ScFv-GFP in vitro Experiments%Anti-HER2-ScFv-GFP融合蛋白靶向结合体外乳腺癌细胞表面受体的研究

    Institute of Scientific and Technical Information of China (English)

    高国辉; 黄奇迪; 王金丹; 杨纪锋; 包兵兵; 胡孝渠

    2011-01-01

    为了研究不同表达系统获得的携带绿色荧光抗HER2单链抗体(Anti-HER2-ScFv-GFP)是否既可靶向结合HER2阳性乳腺癌细胞表面,也可通过观察绿色荧光变化直接判断抗体结合乳腺癌细胞表面后细胞的动态变化,在前期成功构建两种表达系统的基础上,利用Ni2+-NTA亲和层析法纯化来源于真核表达系统pFAST Bac to Bac HTA/Tn-5B1-4和原核表达系统pBAD His B/TOP10的融合蛋白Anti-HER2-ScFv-GFP,设置HER2阳性细胞SKBR3为实验组、HER2阴性细胞MCF7为对照组,分别与之混合24 h后,1×PBS洗脱细胞3次,激光共聚焦显微镜观察到两种不同表达系统获得的融合蛋白在HER2阳性细胞SKBR3 表面分布均有绿色荧光,真核表达的蛋白结合效率明显高于原核表达的蛋白,SKBR3结合高浓度的融合蛋白后细胞表现出皱缩,绿色荧光明显增强,而两种不同来源的融合蛋白与HER2阴性MCF7混合后均易被洗脱.GFP标准品与SKBR3混合后也容易被洗脱.实验表明构建的携带绿色荧光抗HER2单链抗体同时具有靶向结合和报告作用两方面的功能.%The goal of this study was to test the targeting binding efficiency of the fusion protein Anti-HER2-ScFv-GFP on the surface of breast cancer cells. We constructed the eukaryotic expression system pFAST Bac to Bac HT A/Anti-HER2-ScFv-GFP/Tn-5Bl-4 and the prokaryotic system pBAD His B/Anti-HER2-ScFv-GFP/TOP10. And then the fusion protein Anti-HER2-ScFv-GFP was separated to get the purification with Ni2+-NTA argrose from the eukaryotic expression system pFAST Bac to Bac HT A/Tn-5Bl-4 and the prokaryotic expression system pBAD His B/TOP10. Then we incubated SKBR3 (HER2+ cell) and MCF7(HER2-cell) containing the purification of the fusion proteins in 24 h, eluted these cells with 1×PBS three times, examined the targeting binding efficiency of the fusion protein Anti-HER2-ScFv-GFP on the surface of breast cancer cells with laser confocal microscopy system

  17. Evolving trends in biosciences: Multi-purpose proteins - GFP and GFP-like proteins

    Digital Repository Service at National Institute of Oceanography (India)

    Krishna, K.; Ingole, B.S.

    -tagged Rab GTPases have allowed documentation of the dynamics of membrane trafficking. Investigation of virus infection has progressed significantly with the aid of fluorescent protein-tagged virus proteins 27 . Fluorescent proteins can provide...

  18. 绿荧光蛋白基因修饰的大鼠骨髓间充质干细胞复合聚丙交酯-乙交酯膜的形态学观察%Morphological observation of GFP gene-modified mesenchymal stem cells cultured with PLGA substrate

    Institute of Scientific and Technical Information of China (English)

    刘文革; 林海淋

    2010-01-01

    目的 观察绿荧光蛋白(GFP)基因修饰的大鼠骨髓间充质干细胞(rMSCa)与聚丙交酯-乙交酯(PLGA)膜材料复合培养,为后续种子细胞.基因-支架材料-神经营养因子复合方法构建组织工程化脊髓的可行性提供依据.方法 GFP的过表达慢病毒载体(lv-GFP)转染的rMSCs-GFP按8000个细胞/cm2与PLGA膜材料复合培养,以普通培养板上的rMSC-GFP作为对照;荧光显微镜下观察细胞的形态学特性,噻唑蓝法测定每天细胞的生长增殖情况;流式细胞仪测定PLGA膜材料上第3天rMSCs-GFP的细胞周期,用FTTC标记的抗体CD34、CD90和用PE标记的抗CD44、CD106、CD45、CD11b对在膜材料上培养的第3天rMSCs-GFP进行流式细胞鉴定.结果 rMSCs-GFP在PLGA膜上贴壁生长,绝大多数MSCs可见绿色荧光,为成纤维细胞样形态,散在分布,第3天时细胞增多,开始变为多角形,第7天时细胞基本铺满膜,多为多角形和短梭形,与普通培养板上细胞相似,细胞的生长增殖在PLGA膜上与培养板上大致相同,细胞周期也大致相同[G1期细胞占89.7%,132期细胞占3.3%,S期细胞占7.0%,差异无统计学意义(P>0.05)],细胞在PLGA膜上高表达CDg0(99.48%)、CD44(95.25%)、CDl06(77.12%).结论 骨髓间充质干细胞是脊髓组织工程适宜的种子细胞,重组GFP的过表达慢病毒感染的后的MSCs与PLGA膜材料具有良好的组织相容性,可进一步复合方法体外构建组织工程脊髓.%Objective To investigate the feasibility of using PLGA loaded with SD rats' mesenchymal stem cells(rMSCs) transfected with green fluorescent protein (GFP) gene as scaffolds for combinations of molecular, cellular, and tissue-level treatments of spinal cord tissue engineering. Methods rMSCs infected with lentiviral vectors (lv-GFP) were seeded onto PLGA at 8000 cell/cm2, rMSCs-GFP grown under similar conditions on tissue culture plastic as control. The morphology of rMSC-GFP was examined by fluorescence microscopic. The

  19. The effects of SV40 PolyA sequence and its AATAAA signal on upstream GFP gene expression and transcription termination%SV40PolyA序列及其AATAAA信号对上游GFP基因表达及转录终止的影响

    Institute of Scientific and Technical Information of China (English)

    李书平; 冯晶晶; 王红钢; 王秀芳; 吕占军

    2012-01-01

    SV40 PolyA (Simian virus 40 PolyA, also called Poly A) sequence is DNA sequence (240 bp) that possesses the activity of transcription termination and" can add PolyA tail to mRNA. PolyA contains AATAAA hexanucleotide polyadenylation signal. Fourteen copies of Alu in sense orientation (Alul4) were inserted downstream of GFP in pEGFP-Cl to construct pAlul4 plasmid, and then HeLa cells were transiently transfected with pAlul4. Northern blot and fluorescence microscope were used to observe GFP RNA and protein expressions. Our results found that Alu tandem sequence inhibited remarkably GFP gene expression, but produced higher-molecular-mass GFP fusion RNA. PolyA and its sequence that was deleted AATAAA signal in sense or antisense orientation were inserted between GFP and Alu tandem sequence in pAlul4. The results showed that all the inserted PolyA sequences partly eliminated the inhibition induced by Alul4. PolyA sequences without AATAAA signal in sense or antisense orientation still induced transcription termination. Antisense PolyA (PolyAas) was divided into four fragments that all are 60 bp long and the middle two fragments were named 2F2R and 3F3R. 2F2R or 3F3R was inserted upstream of Alu tandem sequence in pAlul4. The molecular mass of GFP fusion RNA increased when the copy number of 2F2R increased. 2F2R can support transcription elongation when 2F2R is located upstream of other 2F2R. Nevertheless, 2F2R located upstream of Alu tandem sequence can induce transcription termination. Inserting one copy or 64 copies of 3F3R in upstream of Alu tandem sequence caused the production., of lower-molecular-mass GFP RNA.%SV40 PolyA(猴空泡病毒PolyA,简称PolyA)序列是有转录终止作用和使转录的mRNA添加PolyA尾的DNA序列(240 bp),含有AATAAA六核苷酸多腺苷化信号(Polyadenylation signal).在pEGFP-C1质粒的GFP基因下游插入14个同向串联的Alu序列(Alu14),构建pAlul4质粒,瞬时转染HeLa细胞,用Northern blot检测和荧光显微镜观察GFP

  20. Mouse bone marrow mesenchymal stem cells(MSCs) transfected with GFP gene by Lentiviral vector%慢病毒介导的GFP转染对小鼠骨髓间充质干细胞表型、增殖和分化能力的影响

    Institute of Scientific and Technical Information of China (English)

    李燕; 陆伟; 竺丽梅; 邵燕; 陈诚; 刘巧; 韩晓冬

    2014-01-01

    The obj ect of this study is to construct the green fluorescent protein(GFP)transfection system by lentiviral vector in mouse bone marrow mesenchymal stem cells(MSCs)invitro.We detected the biological characteristics of mesenchymal stem cells (MSCs ),inclouding cell phenotype,proliferation ability and differentiation ability of mesenchymal stem cells after lentiviral-GFP transfection.Then we observed the myoblasts differentiation ability of mesenchymal stem cells(MSCs)after we confirmed the expression of green fluorescent protein.Bone marrow cell suspensions from mice bone were adherent cultured after erythrocyte broken.We detect the cell surface marker (CD44,CD90,CD105,CD34,CD45 and CD188)of MSCs to identify the purity of mesenchymal stem cells by flow cy-tometry analysis.We transfected mesenchymal stem cells (MSCs)with Lentivirus-GFP for 48 hours,with the multiplicity of infection (MOI)of 1,10,50 and 100,respectively.The transfection efficiency and fluorescence expression were detected by both flow cytometry and immunofluorescence.We evaluated the cell viability by the 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT)test after lentiviral-GFP transfection.MSCs-GFP were induced into myoblasts after the transfection were completed,and the expression of myoblast specific protein desmin andα-SMA were detected by western blot(WB)method.The results of flow cytometry analysis are shown:In accordance with the characteristics of stem cells surface markers,our cultured mesenchymal stem cells (MSCs)expressed CD44,CD90 and CD105,but did not express CD34,CD45 and CD188.The transfection efficiency were 23.45%,93.51%,95.44% and 95.55%,while the transfect MOI were 1,10,50 and 100,respectively.At transfect MOI 10,the transfection efficiency of mesenchymal stem cells (MSCs)was the best,and there was no obvious effect on cell activity observed.After myoblast differentiation invitro,the MSCs-GFP could express desmin andα-SMA.In this study,we constructed the green

  1. 阳离子脂质体介导BFGF/GFP基因对药物性耳蜗损害的防治作用%Protective and rescue effects of cationic liposome - mediated bFGF/GFP on Gentamicin - induced ototoxicity in guinea pig

    Institute of Scientific and Technical Information of China (English)

    尹金淑; 翟所强; 郭维; 胡吟燕; 时利

    2003-01-01

    目的探讨阳离子脂质体(天然碱性脂SA)携带碱性成纤维细胞生长因子/绿色荧光蛋白(bFGF/GFP)基因在豚鼠耳蜗中的表达,以及对庆大霉素所致耳蜗损害的防治作用.方法将36只豚鼠分为3组,预防组右耳园窗注入SA-bFGF/GFP复合物后次日肌肉注射庆大霉素150mg.kg-1.d-18天,治疗组先用庆大霉素8 d后次日右耳给药,对照组单用庆大霉素8 d.分别于实验前后及处死前行听觉脑干诱发电位(ABR)测试.荧光显微镜下观察耳蜗GFP的表达;用耳蜗琥珀酸脱氢酶染色铺片,扫描电镜观察毛细胞的缺失情况.结果荧光显微镜下见双侧耳蜗均有GFP表达.预防和治疗组处死前的双耳ABR阈值与对照组比较差异有显著意义(P<0.01,P<0.05),耳蜗内外毛细胞缺失数与对照组比较差异有显著意义(P<0.01,P<0.05).结论SA脂质体介导的bFGF/GFP基因单耳给药双侧耳蜗均有高效表达,并对庆大霉素所致的耳蜗损害有防治作用.%Objectiye To observe the expression of cationic liposome (Stearylamine SA) mediated bFGF/GFP gene, and evaluate the efficacy of bFGF against the damage of Gentamicin in guinea pig cochlea. Methods 36 guinea pigs were divided into 3 groups. The guinea pigs in the preventive group were inoculated SA- bFGF/GFP complexes into cochleae via round window of the right ear, and were subsequently injected with Gentamicin 150mg. Kg-1 .d-1 for 8 days. The animals in the remedial group were previously administrated Gentamicin for 8 days and then received infusion of SA- bFGF/GFP complexes from nextday. The animals in the control group were only injected with Gentamicin for 8 days. Auditory brainstem response (ABR) was measured preceding test, after test and before the animals were sacrificed, respectively. ~ expression of GFP in cochlea was observed by a fluorescent microscope. The surface preparation of cochlea was made and stained with NBT for counting the absent outer and inner hair cells

  2. Establishment of a transgenic zebrafish model with tetracycline-induced GFP expression in the liver%四环素诱导肝脏特异表达绿色荧光蛋白转基因斑马鱼模型建立

    Institute of Scientific and Technical Information of China (English)

    张力; 刘超; 周昕; 谢英; 刘树锋; 徐增年

    2015-01-01

    目的 探索tet-on四环素诱导表达系统在斑马鱼体内应用策略与技术路线,构建四环素诱导肝脏特异表达绿色荧光蛋白的转基因斑马鱼,为条件型功能基因研究及组织特异转基因斑马鱼疾病模型的建立奠定基础.方法 构建肝脏特异启动子fabp10启动rtTA蛋白表达的重组质粒pfabp10-rtTA,联合pTRE-Tight-BI-AcGFP1质粒转染HeLa细胞后给予doxycycline诱导,Western blot法验证;pfabpl0-rtTA联合pTRE-Tight-BI-AcGFP1质粒注射斑马鱼1-细胞期受精卵后,30 μg/mL doxycycline诱导,荧光筛选稳定整合个体.结果 共转染pfabp10-rtTA与pTRE-Tight-BI-AcGFP1的HeLa细胞经1μg/mL浓度doxycycline诱导培养液诱导,GFP表达量显著高于不加doxy-cycline培养液对照组;筛选获得的稳定整合斑马鱼幼鱼,在浓度为30 μg/mL doxycycline条件下,肝脏明显有绿色荧光表达,对照组幼鱼肝脏位置未有明显绿色荧光.结论 Tet-On四环素诱导表达系统可用于建立四环素调控斑马鱼肝脏特异表达外源基因;利用该技术可建立诱导肝脏表达GFP建立转基因斑马鱼品系,为建立条件型转基因斑马鱼疾病模型、探索肝脏器官发生发育等研究提供良好的模式动物工具.

  3. Effect of mini Ad-ATP7B-GFP on the copper metabolism of skin fibroblasts of Wilson′s disease patients%重组微小腺病毒载体对 Wilson 病患者皮肤成纤维细胞铜代谢的影响

    Institute of Scientific and Technical Information of China (English)

    刘磊磊; 汤其强; 朱迎春

    2016-01-01

    Objective To explore the effect of miniAd-ATP7B-GFP on the copper metabolism of skin fibroblasts of Wilson′s disease ( WD ) patients under high concentration copper medium.Methods Firstly, mini-adenovirus carrier containing human ATP7B gene was built and the mutations of 8 WD patients were detected.Fibroblasts from primary culture of skin of WD patients and normal human were cultivated 72 h in basic medium and medium with the copper concentration of C1(22.3μmol/L), C2(89.2μmol/L), C3 (156.1 μmol/L), C4 (245.3 μmol/L).Then the concentration of copper and protein was detected and copper/protein ratio was calculated.Secondly, miniAd-GFP ( miniAd-GFP group) and miniAd-ATP7B-GFP ( miniAd-ATP7B-GFP group ) were added into WD patients skin fibroblasts respectively, Wilson non-transfection group and normal group were set up as control, and C4 medium was used to culture the cells of four groups for 72 h and 96 h.Then the concentration of copper and protein was detected and copper/protein ratio was calculated.Results Five kinds of mutations were detected from 8 WD patients.The copper/protein ratio of WD patients and normal human in basic medium and the C1 -C3 groups had no statistically significant difference, but in C4 group (WD (1 871.6 ±209.2) ng/mg, normal group (1 267.2 ±188.3) ng/mg) the difference was statistically significant (t=6.075, P<0.01).C3((816.3 ±113.9) ng/mg) and C4 groups had statistically significant difference compared with the basic medium group ( ( 159.2 ± 38.6) ng/mg;WD:χ2 =31.493, normal group:χ2 =30.708, both P<0.01).The copper/protein ratio of 96 h group was higher than 72 h group.Compared with WD non-transfection (96 h:(2 731.2 ±188.7) ng/mg,72 h:(1 901.7 ±219.5) ng/mg) and normal groups, miniAd-ATP7B-GFP group had statistically significant difference both in 96 h ( ( 2 071.0 ±171.8 ) ng/mg ) and 72 h groups ( ( 1 495.5 ±161.4 ) ng/mg;72 h:F=20.130, 96 h: F=51.496,P<0.01).Conclusion MiniAd-ATP7B-GFP has partial improvement on

  4. 鼻粘膜内分泌表达大分子蛋白沿"鼻-脑"通路入脑的研究%The delivery of macromolecular proteins to the brain via"nose-brain"pathway by expressive"NT4-GFP-Ant"re-combinant gene in vivo

    Institute of Scientific and Technical Information of China (English)

    吴昊; 吴江; 孙珉丹; 孙欣; 杨宇

    2010-01-01

    目的 利用分子生物学技术寻求将大分子蛋白类药物沿"鼻-脑"通路长期稳定导入脑内的方法.方法 昆明小鼠8只,随机分为两组,每组4只.分别滴鼻给予小鼠已构建成功的PSSHG/NT4-GFP-Ant穿膜肽重组腺相关病毒和对照组PSSHG/GFP重组腺相关病毒,每次每只鼻孔滴入10μl病毒液,每日1次,连续滴鼻5d.10d后处死小鼠,脑组织冰冻切片,共聚焦显微镜观测脑组织内绿色荧光表达情况.结果 滴鼻PSSHG/NT4-GFP-Ant重组腺相关病毒小鼠组可在鼻粘膜、嗅球、海马观测到绿色荧光表达,其余脑组织内未见荧光表达.而对照组PSSHG/GFP重组腺相关病毒小鼠组鼻粘膜上可见绿色荧光表达,嗅球、海马、其他脑组织未见荧光表达.结论 两种重组腺相关病毒均能感染鼻粘膜细胞,并在鼻粘膜处表达目的 蛋白;用腺相关病毒介导体内分泌表达的单纯大分子蛋白不能沿鼻-脑途径入脑;用腺相关病毒介导体内分泌表达经穿膜肽修饰的大分子的报告蛋白可沿鼻.脑途径入脑.

  5. Single-cell bioluminescence and GFP in biofilm research

    Energy Technology Data Exchange (ETDEWEB)

    Palmer, R.J. Jr, Sayler, G., White, D.C. [Tennessee Univ., Knoxville, TN (United States), Ctr. Env. Biotech; Phiefer, C. [Oak Ridge National Lab., TN (United States), Environmental Sciences Div.

    1996-12-31

    Using flow cells and a combination of microscopy techniques, we can unequivocally identify single bacterial cells that express bioluminescent and fluorescent bioreporters. We have shown that, for attached cells, bioluminescence output within a bacterial strain can vary greatly from cell to cell.

  6. Highly fluorescent benzofuran derivatives of the GFP chromophore

    DEFF Research Database (Denmark)

    Christensen, Mikkel Andreas; Jennum, Karsten Stein; Abrahamsen, Peter Bæch

    2012-01-01

    Intramolecular cyclization reactions of Green Fluorescent Protein chromophores (GFPc) containing an arylethynyl ortho-substituent at the phenol ring provide new aryl-substituted benzofuran derivatives of the GFPc. Some of these heteroaromatic compounds exhibit significantly enhanced fluorescence...

  7. Measuring intracellular redox conditions using GFP-based sensors

    DEFF Research Database (Denmark)

    Björnberg, Olof; Ostergaard, Henrik; Winther, Jakob R

    2006-01-01

    Recent years have seen the development of methods for analyzing the redox conditions in specific compartments in living cells. These methods are based on genetically encoded sensors comprising variants of Green Fluorescent Protein in which vicinal cysteine residues have been introduced at solvent......-exposed positions. Several mutant forms have been identified in which formation of a disulfide bond between these cysteine residues results in changes of their fluorescence properties. The redox sensors have been characterized biochemically and found to behave differently, both spectroscopically and in terms...... of redox properties. As genetically encoded sensors they can be expressed in living cells and used for analysis of intracellular redox conditions; however, which parameters are measured depends on how the sensors interact with various cellular redox components. Results of both biochemical and cell...

  8. 携带GFP绿色荧光标记的重组BAC-HSV-1HF株的构建及其子代病毒的特性研究%Construction of a Recombinant BAC-HSV-1 Strain HF with a GFP Reporter Gene and Characterization of Its Infectious Progeny Virus

    Institute of Scientific and Technical Information of China (English)

    刘新静; 宋波; 卢甲盟; 王青志; 韩志强; 许予明

    2011-01-01

    本研究旨在构建由细菌人工染色体(Bacteria artificial chromosome,BAC)携带的单纯疱疹I型病毒质粒及携带绿色荧光蛋白(Green fluorescent protein,GFP)的重组型BAC-HSV-1感染性子代病毒.构建了携带HSV-1同源臂的质粒C223-UL43左臂-UL47右臂.将该质粒线性化后与HSV-1基因组共转染至Vero细胞,通过真核细胞内同源重组产生了含有GFP报告基因的BAC-HSV-1重组病毒,噬斑纯化筛选出阳性重组病毒,并再次感染Vero细胞,Hirt法提取BAC-HSV-1环形基因组并将其电穿孔入DH10B感受态细胞,由PCR和酶切法鉴定BAC-HSV-1质粒.为研究BAC-HSV-1子代病毒的生物学特性,将实验组和对照组细胞分别给予BAC-HSV-1质粒和HSV-1基因组DNA,收取病变细胞的上清液,以MOI=0.1再次感染Vero细胞,半数组织培养感染剂量(50%tis-sue culture infective dose,TCID50)法测定两组的病毒滴度.PCR和酶切法分别鉴定BAC-HSV-1,结果示BAC-HSV-1构建成功.TCID50法测定实验组和对照组病毒滴度,经统计学分析两组病毒滴度间差异无统计学意义(P>0.05).本研究成功地构建了真核细胞和原核细胞间穿梭的HSV-1-BAC重组病毒/质粒.%To construct the plasmid of BAC-HSV-1 with GFP reporter gene and research the biological property of its infectious progeny virus. We constructed the plasmid C223-UL43-left-arms-UL47-rightarms which carried the homologous sequences of HSV-1. Liposome embedding method was used to transfect HSV-1 genome and the plasmid C223-UL43-left-arms-UL47-right-arms linearized by Mlu I digestion into Vero cells. After the successful homologous recombination in the eukaryotic cells, the recombinant BAC-HSV-1 with GFP reporter gene was generated. Then, the positive CPE were taken by plaque purification and by hirt extraction during the moment of the circularization of HSV-1 DNA, and the plasmid of BAC -HSV-1 was acquired. Electroporation was used to transfect the BAC -HSV-1 into DH10B, and then the

  9. Increased cardiogenesis in P19-GFP teratocarcinoma cells expressing the propeptide IGF-1Ea

    Energy Technology Data Exchange (ETDEWEB)

    Poudel, Bhawana [Heart Science Centre, National Heart and Lung Institute, Imperial College, London (United Kingdom); Bilbao, Daniel [EMBL, Mouse Biology Unit, Monterotondo (Italy); Sarathchandra, Padmini; Germack, Renee [Heart Science Centre, National Heart and Lung Institute, Imperial College, London (United Kingdom); Rosenthal, Nadia [Heart Science Centre, National Heart and Lung Institute, Imperial College, London (United Kingdom); Australian Regenerative Medicine Institute, Monash University, Melbourne (Australia); Santini, Maria Paola, E-mail: m.santini@imperial.ac.uk [Heart Science Centre, National Heart and Lung Institute, Imperial College, London (United Kingdom)

    2011-12-16

    Highlights: Black-Right-Pointing-Pointer In this study, we explored the function of IGF-1Ea propeptide in inducing cardiogenesis of stem cells. Black-Right-Pointing-Pointer IGF-1Ea promoted cardiac mesodermal induction in uncommitted cells. Black-Right-Pointing-Pointer Under differentiation condition, IGF-1Ea increased expression of cardiac differentiation markers. Black-Right-Pointing-Pointer Furthermore, it promoted formation of finely organized sarcomeric structure. Black-Right-Pointing-Pointer IGF-1Ea propeptide may be a good candidate to improve production of cardiomyocytes from pluripotent cells. -- Abstract: The mechanism implicated in differentiation of endogenous cardiac stem cells into cardiomyocytes to regenerate the heart tissue upon an insult remains elusive, limiting the therapeutical goals to exogenous cell injection and/or gene therapy. We have shown previously that cardiac specific overexpression of the insulin-like growth factor 1 propeptide IGF-1Ea induces beneficial myocardial repair after infarct. Although the mechanism is still under investigation, the possibility that this propeptide may be involved in promoting stem cell differentiation into the cardiac lineage has yet to be explored. To investigate whether IGF-1Ea promote cardiogenesis, we initially modified P19 embryonal carcinoma cells to express IGF-1Ea. Taking advantage of their cardiomyogenic nature, we analyzed whether overexpression of this propeptide affected cardiac differentiation program. The data herein presented showed for the first time that constitutively overexpressed IGF-1Ea increased cardiogenic differentiation program in both undifferentiated and DMSO-differentiated cells. In details, IGF-1Ea overexpression promoted localization of alpha-actinin in finely organized sarcomeric structure compared to control cells and upregulated the cardiac mesodermal marker NKX-2.5 and the ventricular structural protein MLC2v. Furthermore, activated IGF-1 signaling promoted cardiac mesodermal induction in undifferentiated cells independently of cell proliferation. This analysis suggests that IGF-1Ea may be a good candidate to improve both in vitro production of cardiomyocytes from pluripotent stem cells and in vivo activation of the differentiation program of cardiac progenitor cells.

  10. A novel model of demyelination and remyelination in a GFP-transgenic zebrafish

    Directory of Open Access Journals (Sweden)

    Yangwu Fang

    2014-12-01

    Full Text Available Demyelinating diseases consist of a variety of autoimmune conditions in which the myelin sheath is damaged due to genetic and/or environmental factors. During clinical treatment, some patients undergo partial remyelination, especially during the early disease stages. However, the mechanisms that regulate demyelination remain unclear. The myelin structure, myelin formation and myelin-related gene expression are highly conserved between mammals and zebrafish. Therefore, the zebrafish is an ideal model organism to study myelination. In this study, we generated a transgenic zebrafish Tg(mbp:nfsB-egfp expressing a fusion protein composed of enhanced green fluorescent protein (EGFP and NTR from the myelin basic protein (mbp promoter. Tg(mbp:nfsB-egfp expressed NTR-EGFP reproducibly and hereditarily in oligodendrocytes along the spinal cord. Treatment of zebrafish larvae Tg(mbp:nfsB-egfp with metronidazole (Mtz resulted in the selective ablation of oligodendrocytes and led to demyelination, accompanied by behavioral changes, including decreased total movement distance, velocity, total movement time and fast movement time. After withdrawal of Mtz for a seven day recovery period, the expression of EGFP and MBP protein was observed again which indicates remyelination. Additionally, locomotor capacity was restored. Collectively, Tg(mbp:nfsB-egfp, a heritable and stable transgenic line, provides a novel, powerful tool to study the mechanisms of demyelination and remyelination.

  11. How far can a single hydrogen bond tune the spectral properties of the GFP chromophore?

    DEFF Research Database (Denmark)

    Kiefer, Hjalte; Lattouf, Elie; Persen, Natascha Wardinghus;

    2015-01-01

    absorption spectrum is measured. Our theoretical account of the spectral shape reveals that the anionic 0–0 transition (464 nm) is blue-shifted compared to that of the wild-type protein (478 nm) due to the stronger H-bond in the dimer, and represents an upper bound for that of the isolated anion. At the same...

  12. Stochastic dynamic study of optical transition properties of single GFP-like molecules.

    Science.gov (United States)

    Lin, Hanbing; Yuan, Jian-Min

    2016-03-01

    Due to high fluctuations and quantum uncertainty, the processes of single-molecules should be treated by stochastic methods. To study fluorescence time series and their statistical properties, we have applied two stochastic methods, one of which is an analytic method to study the off-time distributions of certain fluorescence transitions and the other is Gillespie's method of stochastic simulations. These methods have been applied to study the optical transition properties of two single-molecule systems, GFPmut2 and a Dronpa-like molecule, to yield results in approximate agreement with experimental observations on these systems. Rigorous oscillatory time series of GFPmut2 before it unfolds in the presence of denaturants have not been obtained based on the stochastic method used, but, on the other hand, the stochastic treatment puts constraints on the conditions under which such oscillatory behavior is possible. Furthermore, a sensitivity analysis is carried out on GFPmut2 to assess the effects of transition rates on the observables, such as fluorescence intensities.

  13. Endocytosis of a functionally enhanced GFP-tagged transferrin receptor in CHO cells.

    Directory of Open Access Journals (Sweden)

    Qi He

    Full Text Available The endocytosis of transferrin receptor (TfR has served as a model to study the receptor-targeted cargo delivery system for cancer therapy for many years. To accurately evaluate and optically measure this TfR targeting delivery in vitro, a CHO cell line with enhanced green fluorescent protein (EGFP-tagged human TfR was established. A chimera of the hTfR and EGFP was engineered by fusing EGFP to the amino terminus of hTfR. Data were provided to demonstrate that hTfR-EGFP chimera was predominantly localized on the plasma membrane with some intracellular fluorescent structures on CHO cells and the EGFP moiety did not affect the endocytosis property of hTfR. Receptor internalization occurred similarly to that of HepG2 cells expressing wild-type hTfR. The internalization percentage of this chimeric receptor was about 81 ± 3% of wild type. Time-dependent co-localization of hTfR-EGFP and PE-conjugated anti-hTfR mAb in living cells demonstrated the trafficking of mAb-receptor complexes through the endosomes followed by segregation of part of the mAb and receptor at the late stages of endocytosis. The CHO-hTfR cells preferentially took up anti-hTfR mAb conjugated nanoparticles. This CHO-hTfR cell line makes it feasible for accurate evaluation and visualization of intracellular trafficking of therapeutic agents conjugated with transferrin or Abs targeting the hTfRs.

  14. Targeted expression of GFP in the hair follicle using ex vivo viral transduction.

    Science.gov (United States)

    Hoffman, Robert M; Li, Lingna

    2008-03-17

    There are many cell types in the hair follicle, including hair matrix cells which form the hair shaft and stem cells which can initiate the hair shaft during early anagen, the growth phase of the hair cycle, as well as pluripotent stem cells that play a role in hair follicle growth but have the potential to differentiate to non-follicle cells such as neurons. These properties of the hair follicle are discussed. The various cell types of the hair follicle are potential targets for gene therapy. Gene delivery system for the hair follicle using viral vectors or liposomes for gene targeting to the various cell types in the hair follicle and the results obtained are also discussed [corrected].

  15. Targeted Expression of GFP in the Hair Follicle Using Ex Vivo Viral Transduction

    OpenAIRE

    Hoffman, Robert M.; Li, Lingna

    2008-01-01

    The hair follicle is a highly complex appendage of the skin containing a multiplicity of cell types. The follicle undergoes constant cycling through the life of the organism including growth and resorption with growth dependent on specific stem cells. The targeting of the follicle by genes and stem cells to change its properties, in particular, the nature of the hair shaft is, discussed. Hair follicle delivery systems are described, such as liposomes and viral vectors for gene therapy. The na...

  16. Dynamic behavior of GFP-CLIP-170 reveals fast protein turnover on microtubule plus ends.

    NARCIS (Netherlands)

    K.A. Drägestein (Katharina Asja); W.A. van Cappellen (Gert); J.A.J. van Haren (Jeffrey); G.D. Tsibidis (George); A.S. Akhmanova (Anna); T.A. Knoch (Tobias); F.G. Grosveld (Frank); N.J. Galjart (Niels)

    2008-01-01

    textabstractMicrotubule (MT) plus end – tracking proteins (+TIPs) specifi cally recognize the ends of growing MTs. +TIPs are involved in diverse cellular processes such as cell division, cell migration, and cell polarity. Although +TIP tracking is important for these processes, the mechanisms underl

  17. Fast VLSI Implementation of Modular Inversion in Galois Field GF(p)

    Institute of Scientific and Technical Information of China (English)

    周涛; 吴行军; 白国强; 陈弘毅

    2003-01-01

    Modular inversion is one of the key arithmetic operations in public key cryptosystems, so low-cost, high-speed hardware implementation is absolutely necessary. This paper presents an algorithm for prime fields for hardware implementation. The algorithm involves only ordinary addition/subtraction and does not need any modular operations, multiplications or divisions. All of the arithmetic operations in the algorithm can be accomplished by only one adder, so it is very suitable for fast very large scale integration (VLSI) implementation. The VLSI implementation of the algorithm is also given with good performance and low silicon penalty.

  18. Simultaneous imaging of GFP, CFP and collagen in tumors in vivo using multiphoton microscopy

    Directory of Open Access Journals (Sweden)

    Segall Jeffrey E

    2005-05-01

    Full Text Available Abstract Background The development of multiphoton laser scanning microscopy has greatly facilitated the imaging of living tissues. However, the use of genetically encoded fluorescent proteins to distinguish different cell types in living animals has not been described at single cell resolution using multiphoton microscopy. Results Here we describe a method for the simultaneous imaging, by multiphoton microscopy, of Green Fluorescent Protein, Cyan Fluorescent Protein and collagen in vivo in living tumors. This novel method enables: 1 the simultaneous visualization of overall cell shape and sub-cellular structures such as the plasma membrane or proteins of interest in cells inside living animals, 2 direct comparison of the behavior of single cells from different cell lines in the same microenvironment in vivo. Conclusion Using this multi-fluor, multiphoton technique, we demonstrate that motility and metastatic differences between carcinoma cells of differing metastatic potential can be imaged in the same animal simultaneously at sub-cellular resolution.

  19. A sperm-mediated GFP gene transfer in amphioxus (Branchiostoma belcheri tsingtaoense)

    Institute of Scientific and Technical Information of China (English)

    YU Dan; ZHANG Peijun

    2005-01-01

    @@ The cephalochordate amphioxus is the closest living invertebrate relative of the vertebrate and has emerged as an important animal model for evolutionary developmental biology research[1]. Many insights into the evolution of the vertebrate body plan can be gained by comparing vertebrate embryogenesis with that of the amphioxus. Investigation of the gene regulation during amphioxus embryogenesis will provide us clues to clarify how changes of gene regulation affect the body plan evolution at this turning point and thus will throw light on the origin and evolution of the vertebrate.

  20. Generation of eGFP and Cre knockin rats by CRISPR/Cas9.

    Science.gov (United States)

    Ma, Yuanwu; Ma, Jing; Zhang, Xu; Chen, Wei; Yu, Lei; Lu, Yingdong; Bai, Lin; Shen, Bin; Huang, Xingxu; Zhang, Lianfeng

    2014-09-01

    The type II bacterial CRISPR/Cas [clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated (Cas)] system is a very valuable genome engineering tool, which has been widely used in genome editing of a variety of organisms. Previously, we generated floxed alleles in rats by CRISPR/Cas9. Here, we successfully use a two-cut strategy with one circular vector, which contains the exogenous cDNAs with homology arm regions, in generating knockin rats at the Trdmt1, Nestin and Cck loci. The efficiency of CRISPR/Cas9-mediated knockin was up to 54%. Furthermore, by crossing the Nestin-Cre rat with the Dnmt3b floxed rat and Cck-Cre with the Dnmt1 floxed rat, we detected Cre/loxP-mediated recombination in the F1 generation of rats. We also show that the knockin alleles were germline transmitted. These results provided a simple and flexible engineering strategy for the establishment of knockin rats.

  1. Co-transfer of gfp, CHS and hptII genes into Oncidium Sharry Baby ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-08-04

    Aug 4, 2008 ... PLB, concentration of DNA, age of PLB, spermidine and. CaCl2 in ... DC 200) was attached to the fluorescence microscope to capture the image in ..... Liau CH, You SJ, Prasad V, Hsiao, HH, Lu JC, Yang NS, Chan MT. (2003).

  2. A Linked Series of Laboratory Exercises in Molecular Biology Utilizing Bioinformatics and GFP

    Science.gov (United States)

    Medin, Carey L.; Nolin, Katie L.

    2011-01-01

    Molecular biologists commonly use bioinformatics to map and analyze DNA and protein sequences and to align different DNA and protein sequences for comparison. Additionally, biologists can create and view 3D models of protein structures to further understand intramolecular interactions. The primary goal of this 10-week laboratory was to introduce…

  3. A Linked Series of Laboratory Exercises in Molecular Biology Utilizing Bioinformatics and GFP

    Science.gov (United States)

    Medin, Carey L.; Nolin, Katie L.

    2011-01-01

    Molecular biologists commonly use bioinformatics to map and analyze DNA and protein sequences and to align different DNA and protein sequences for comparison. Additionally, biologists can create and view 3D models of protein structures to further understand intramolecular interactions. The primary goal of this 10-week laboratory was to introduce…

  4. Tracing human mitochondrial complex I assembly by use of GFP-tagged subunits

    NARCIS (Netherlands)

    Dieteren, C.E.J.; Koopman, W.J.H.; Nijtmans, L.G.J.

    2009-01-01

    Disturbances in the assembly of mitochondrial complex I (CI) are a frequent cause of mitochondrial disorders. Several lines of evidence hint at a semi-sequential assembly pathway, in which the 45 individual subunits that form the holoenzyme are pieced together by means of smaller intermediates. To u

  5. Photophysics, Dynamics, and Energy Transfer in Rigid Mimics of GFP-based Systems.

    Science.gov (United States)

    Dolgopolova, Ekaterina A; Rice, Allison M; Smith, Mark D; Shustova, Natalia B

    2016-08-01

    Engineering of novel systems capable of efficient energy capture and transfer in a predesigned pathway could potentially boost applications varying from organic photovoltaics to catalytic platforms and have implications for energy sustainability and green chemistry. While light-harvesting properties of different materials have been studied for decades, recently, there has been great progress in the understanding and modeling of short- and long-range energy transfer processes through utilization of metal-organic frameworks (MOFs). In this Forum Article, the recent advances in efficient multiple-chromophore coupling in well-defined metal-organic materials through mimicking a protein system possessing near 100% energy transfer are discussed. Utilization of a MOF as an efficient replica of a protein β-barrel to maintain chromophore emission was also demonstrated. Furthermore, we established a novel dependence of a photophysical response on an electronic configuration for chromophores with the benzylidene imidazolinone core. For that, we prepared 16 chromophores, in which the benzylidene imidazolinone core was modified with electron-donating and electron-withdrawing substituents. To establish the structure-dependent photophysical properties of the prepared chromophores, 11 novel molecular structures were determined by single-crystal X-ray diffraction. These findings allow one to predict the chromophore emission profile inside a rigid framework as a function of the substituent, a key parameter for achieving the spectral overlap necessary to study and increase resonance energy transfer efficiency in MOF-based materials.

  6. Analysis of nuclear export using photoactivatable GFP fusion proteins and interspecies heterokaryons.

    Science.gov (United States)

    Nakrieko, Kerry-Ann; Ivanova, Iordanka A; Dagnino, Lina

    2010-01-01

    In this chapter, we review protocols for the analysis of nucleocytoplasmic shuttling of transcription factors and nuclear proteins, using two different approaches. The first involves the use of photoactivatable forms of the protein of interest by fusion to photoactivatable green fluorescent protein to follow its movement out of the nucleus by live-cell confocal microscopy. This methodology allows for the kinetic characterization of protein movements as well as measurement of steady-state levels. In a second procedure to assess the ability of a nuclear protein to move into and out of the nucleus, we describe the use of interspecies heterokaryon assays, which provide a measurement of steady-state distribution. These technologies are directly applicable to the analysis of nucleocytoplasmic movements not only of transcription factors, but also other nuclear proteins.

  7. In vivo analysis of interactions between GFP-labeled microfilaments and plastid stromules

    Directory of Open Access Journals (Sweden)

    Kwok Ernest Y

    2004-02-01

    Full Text Available Abstract Background Plastid stromules are stroma-filled tubules that extend from the surface of plastids in higher plants and allow the exchange of protein molecules between plastids. These structures are highly dynamic; stromules change both their shape and position in the cytoplasm very rapidly. Previous studies with microfilament inhibitors indicated that stromule shape and movement are dependent on the actin cytoskeleton. To learn more about the nature of the interactions of stromules and the cytoskeleton, we imaged fluorescently-labeled microfilaments and plastids. Results We have used Arabidopsis thaliana plants expressing green fluorescent protein fused to the human actin-binding protein talin to observe microfilaments and their relationship to stromules in vivo. Microfilaments were observed in close contact with stromules and plastid bodies of hypocotyl epidermis. Time-lapse confocal microscopy revealed that microfilament rearrangements were associated with changes in plastid and stromule morphology and position. We also observed close interactions between mitochondria and stromules in double-labeled cells. Conclusion Our results indicate a correlation between the rearrangement of microfilaments and changes in the shape and position of plastids and stromules. Stromules interact with microfilaments that may also be utilized by mitochondria and other organelles. The interaction of microfilaments and plastids is likely to be mediated by actin-binding proteins on the plastid envelope membrane.

  8. Construction of recombinant ZNF230/GFP fused plasmids and their expression and cellular localization

    DEFF Research Database (Denmark)

    Xu, Wen-Ming; Zhang, Si-Zhong; Qiu, Wei-Min

    2004-01-01

    To use green fluorescent protein as a marker to study the localization of the fusion protein, the mutant full length cDNAs of human ZNF230 and mouse znf230 with their stop codon TGA changed to TGG were obtained by PCR amplification, and then cloned into pGEM-Teasy vector. After the double enzyme...... with high efficiency. When transfected with the constructed recombinant pEGFP-ZNF230 vector, the ZNF230 protein localizes mainly on the nucleus....

  9. gfp-based N-acyl homoserine-lactone sensor systems for detection of bacterial communication

    DEFF Research Database (Denmark)

    Andersen, Jens Bo; Heydorn, Arne; Hentzer, Morten

    2001-01-01

    In order to perform single-cell analysis and online studies of N-acyl homoserine lactone (AHL)-mediated communication among bacteria, components of the Vibrio fischeri quorum sensor encoded by luxR-P-luxI have been fused to modified versions of gfpmut3* genes encoding unstable green fluorescent...... detection at the single-cell level and allowed for real-time measurements of fluctuations in AHL concentrations. This green fluorescent AHL sensor provides a state-of-the art tool for studies of communication between the individuals present in mixed bacterial communities....... proteins. Bacterial strains harboring this green fluorescent sensor detected a broad spectrum of AHL molecules and were capable of sensing the presence of 5 nM N-3-oxohexanoyl-L-homoserine lactone in the surroundings. In combination with epifluorescent microscopy, the sensitivity of the sensor enabled AHL...

  10. Glutamic acid decarboxylase isoform distribution in transgenic mouse septum: an anti-GFP immunofluorescence study.

    Science.gov (United States)

    Verimli, Ural; Sehirli, Umit S

    2016-09-01

    The septum is a basal forebrain region located between the lateral ventricles in rodents. It consists of lateral and medial divisions. Medial septal projections regulate hippocampal theta rhythm whereas lateral septal projections are involved in processes such as affective functions, memory formation, and behavioral responses. Gamma-aminobutyric acidergic neurons of the septal region possess the 65 and 67 isoforms of the enzyme glutamic acid decarboxylase. Although data on the glutamic acid decarboxylase isoform distribution in the septal region generally appears to indicate glutamic acid decarboxylase 67 dominance, different studies have given inconsistent results in this regard. The aim of this study was therefore to obtain information on the distributions of both of these glutamic acid decarboxylase isoforms in the septal region in transgenic mice. Two animal groups of glutamic acid decarboxylase-green fluorescent protein knock-in transgenic mice were utilized in the experiment. Brain sections from the region were taken for anti-green fluorescent protein immunohistochemistry in order to obtain estimated quantitative data on the number of gamma-aminobutyric acidergic neurons. Following the immunohistochemical procedures, the mean numbers of labeled cells in the lateral and medial septal nuclei were obtained for the two isoform groups. Statistical analysis yielded significant results which indicated that the 65 isoform of glutamic acid decarboxylase predominates in both lateral and medial septal nuclei (unpaired two-tailed t-test p glutamic acid decarboxylase isoform 65 in the septal region in glutamic acid decarboxylase-green fluorescent protein transgenic mice.

  11. Fluorescence fluctuation analysis of BACE1-GFP fusion protein in cultured HEK293 cells

    Science.gov (United States)

    Gardeen, Spencer; Johnson, Joseph L.; Heikal, Ahmed A.

    2016-10-01

    Beta-site APP cleaving enzyme 1 (BACE1) is a type I transmembrane aspartyl protease. In the amyloidogenic pathway, BACE1 provides β-secretase activity that cleaves the amyloid precursor protein (APP) that leads to amyloid beta (Aβ) peptides. The aggregation of these Aβ will ultimately results in amyloid plaque formation, a hallmark of Alzheimer's disease (AD). Amyloid aggregation leads to progressive memory impairment and neural loss. Recent detergent protein extraction studies suggest that the untreated BACE1 protein forms a dimer that has significantly higher catalytic activity than its monomeric counterpart. Here, we examine the dimerization hypothesis of BACE1 in cultured HEK293 cells using fluorescence correlation spectroscopy (FCS). Cells were transfected with a BACE1-EGFP fusion protein construct and imaged using confocal and DIC microscopy to monitor labeled BACE1 localization and distribution within the cell. Our one-photon fluorescence fluctuation autocorrelation of BACE1- EGFP on the plasma membrane of HEK cells is modeled using two diffusing species on the plasma membrane with estimated diffusion coefficients of 1.39 x 10-7 cm2/sec and 2.8 x 10-8 cm2/sec under resting conditions and STA-200 inhibition, respectively. Anomalous diffusion model also provided adequate description of the observed autocorrelation function of BACE1- EGFP on the plasma membrane with an estimate exponent (α) of 0.8 and 0.5 for resting and STA-200 treated cells, respectively. The corresponding hydrodynamic radius of this transmembrane fusion protein was estimated using the measured diffusion coefficients assuming both Stokes-Einstein and Saffman-Delbruck models. Our results suggest a complex diffusion pattern of BACE1-EGFP on the plasma membrane of HEK cells with the possibility for dimer formation, especially under STA-200 inhibition.

  12. Safe sorting of GFP-transduced live cells for subsequent culture using a modified FACS vantage

    DEFF Research Database (Denmark)

    Sørensen, T U; Gram, G J; Nielsen, S D

    1999-01-01

    BACKGROUND: A stream-in-air cell sorter enables rapid sorting to a high purity, but it is not well suited for sorting of infectious material due to the risk of airborne spread to the surroundings. METHODS: A FACS Vantage cell sorter was modified for safe use with potentially HIV infected cells. S...... culture. CONCLUSIONS: Sorting of live infected cells can be performed safely and with no deleterious effects on vector expression using the modified FACS Vantage instrument.......BACKGROUND: A stream-in-air cell sorter enables rapid sorting to a high purity, but it is not well suited for sorting of infectious material due to the risk of airborne spread to the surroundings. METHODS: A FACS Vantage cell sorter was modified for safe use with potentially HIV infected cells...... culture. RESULTS: The bacteriophage sorting showed that the biologically active material was confined to the sorting chamber. A failure mode simulating a nozzle blockage resulted in detectable droplets inside the sorting chamber, but no droplets could be detected when an additional air suction from...

  13. Comparison of mouse mammary gland imaging techniques and applications: Reflectance confocal microscopy, GFP Imaging, and ultrasound

    Directory of Open Access Journals (Sweden)

    Cotarla Ion

    2008-01-01

    Full Text Available Abstract Background Genetically engineered mouse models of mammary gland cancer enable the in vivo study of molecular mechanisms and signaling during development and cancer pathophysiology. However, traditional whole mount and histological imaging modalities are only applicable to non-viable tissue. Methods We evaluated three techniques that can be quickly applied to living tissue for imaging normal and cancerous mammary gland: reflectance confocal microscopy, green fluorescent protein imaging, and ultrasound imaging. Results In the current study, reflectance confocal imaging offered the highest resolution and was used to optically section mammary ductal structures in the whole mammary gland. Glands remained viable in mammary gland whole organ culture when 1% acetic acid was used as a contrast agent. Our application of using green fluorescent protein expressing transgenic mice in our study allowed for whole mammary gland ductal structures imaging and enabled straightforward serial imaging of mammary gland ducts in whole organ culture to visualize the growth and differentiation process. Ultrasound imaging showed the lowest resolution. However, ultrasound was able to detect mammary preneoplastic lesions 0.2 mm in size and was used to follow cancer growth with serial imaging in living mice. Conclusion In conclusion, each technique enabled serial imaging of living mammary tissue and visualization of growth and development, quickly and with minimal tissue preparation. The use of the higher resolution reflectance confocal and green fluorescent protein imaging techniques and lower resolution ultrasound were complementary.

  14. Visualization of symbiotic tissue in intact root nodules of Vicia tetrasperma using GFP-marked Rhizobium leguminosarum bv. viciae

    National Research Council Canada - National Science Library

    Chovanec, P; Hovorka, O; Novák, K

    2008-01-01

    In rhizobial symbiosis with legume plant hosts, the symbiotic tissue in the root nodules of indeterminate type is localized to the basal part of the nodule where the symbiotic zones contain infected cells (IC...

  15. Brassica juncea Lines with Substituted Chimeric GFP-CENH3 Give Haploid and Aneuploid Progenies on Crossing with Other Lines

    OpenAIRE

    Watts, Anshul; Singh, Sunil K.; Bhadouria, Jyoti; Naresh, Vasupalli; Bishoyi, Ashok K.; K.A. Geetha; Chamola, Rohit; Pattanayak, Debasis; Bhat, Shripad R.

    2017-01-01

    Haploids and doubled haploids are invaluable for basic genetic studies and in crop improvement. A novel method of haploid induction through genetic engineering of the Centromere Histone Protein gene, CENH3, has been demonstrated in Arabidopsis. The present study was undertaken to develop haploid inducer (HI) lines of Brassica juncea based on the principles elaborated in Arabidopsis. B. juncea was found to carry three copies of CENH3 which generated five different transcripts, of which three t...

  16. X-Ray Crystal Structure and Properties of Phanta, a Weakly Fluorescent Photochromic GFP-Like Protein.

    Directory of Open Access Journals (Sweden)

    Craig Don Paul

    Full Text Available Phanta is a reversibly photoswitching chromoprotein (ΦF, 0.003, useful for pcFRET, that was isolated from a mutagenesis screen of the bright green fluorescent eCGP123 (ΦF, 0.8. We have investigated the contribution of substitutions at positions His193, Thr69 and Gln62, individually and in combination, to the optical properties of Phanta. Single amino acid substitutions at position 193 resulted in proteins with very low ΦF, indicating the importance of this position in controlling the fluorescence efficiency of the variant proteins. The substitution Thr69Val in Phanta was important for supressing the formation of a protonated chromophore species observed in some His193 substituted variants, whereas the substitution Gln62Met did not significantly contribute to the useful optical properties of Phanta. X-ray crystal structures for Phanta (2.3 Å, eCGP123T69V (2.0 Å and eCGP123H193Q (2.2 Å in their non-photoswitched state were determined, revealing the presence of a cis-coplanar chromophore. We conclude that changes in the hydrogen-bonding network supporting the cis-chromophore, and its contacts with the surrounding protein matrix, are responsible for the low fluorescence emission of eCGP123 variants containing a His193 substitution.

  17. X-Ray Crystal Structure and Properties of Phanta, a Weakly Fluorescent Photochromic GFP-Like Protein.

    Science.gov (United States)

    Don Paul, Craig; Traore, Daouda A K; Olsen, Seth; Devenish, Rodney J; Close, Devin W; Bell, Toby D M; Bradbury, Andrew; Wilce, Matthew C J; Prescott, Mark

    2015-01-01

    Phanta is a reversibly photoswitching chromoprotein (ΦF, 0.003), useful for pcFRET, that was isolated from a mutagenesis screen of the bright green fluorescent eCGP123 (ΦF, 0.8). We have investigated the contribution of substitutions at positions His193, Thr69 and Gln62, individually and in combination, to the optical properties of Phanta. Single amino acid substitutions at position 193 resulted in proteins with very low ΦF, indicating the importance of this position in controlling the fluorescence efficiency of the variant proteins. The substitution Thr69Val in Phanta was important for supressing the formation of a protonated chromophore species observed in some His193 substituted variants, whereas the substitution Gln62Met did not significantly contribute to the useful optical properties of Phanta. X-ray crystal structures for Phanta (2.3 Å), eCGP123T69V (2.0 Å) and eCGP123H193Q (2.2 Å) in their non-photoswitched state were determined, revealing the presence of a cis-coplanar chromophore. We conclude that changes in the hydrogen-bonding network supporting the cis-chromophore, and its contacts with the surrounding protein matrix, are responsible for the low fluorescence emission of eCGP123 variants containing a His193 substitution.

  18. GFP-specific CD8 T cells enable targeted cell depletion and visualization of T-cell interactions.

    Science.gov (United States)

    Agudo, Judith; Ruzo, Albert; Park, Eun Sook; Sweeney, Robert; Kana, Veronika; Wu, Meng; Zhao, Yong; Egli, Dieter; Merad, Miriam; Brown, Brian D

    2015-12-01

    There are numerous cell types with scarcely understood functions, whose interactions with the immune system are not well characterized. To facilitate their study, we generated a mouse bearing enhanced green fluorescent protein (EGFP)-specific CD8(+) T cells. Transfer of the T cells into EGFP reporter animals can be used to kill EGFP-expressing cells, allowing selective depletion of desired cell types, or to interrogate T-cell interactions with specific populations. Using this system, we eliminate a rare EGFP-expressing cell type in the heart and demonstrate its role in cardiac function. We also show that naive T cells are recruited into the mouse brain by antigen-expressing microglia, providing evidence of an immune surveillance pathway in the central nervous system. The just EGFP death-inducing (Jedi) T cells enable visualization of a T-cell antigen. They also make it possible to utilize hundreds of existing EGFP-expressing mice, tumors, pathogens and other tools, to study T-cell interactions with many different cell types, to model disease states and to determine the functions of poorly characterized cell populations.

  19. Hardware Realization of Fast Multi-Scalar Elliptic Curve Point Multiplication by Reducing the Hamming Weights Over GF(p

    Directory of Open Access Journals (Sweden)

    Nagaraja Shylashree

    2014-09-01

    Full Text Available We present a new hardware realization of fast elliptic curve Multi-Scalar Point Multiplication (MSPM using the sum of products expansion of the scalars. In Elliptic curve point Multiplication latency depends on the number of one’s (Hamming Weight in the binary representation of the scalar multiplier. By reducing the effective number of one’s in the multiplier, the multiplication speed is automatically increased. Therefore we describe a new method of effectively reducing the Hamming weight of the scalar multipliers thereby reduces the number of Point Adders when multi scalar multiplication is needed. The increase in speed achieved outweighs the hardware cost and complexity.

  20. Studies on the colonization of axenically grown tomato plants by a GFP-tagged strain of Clavibacter michiganensis subsp. michiganensis

    NARCIS (Netherlands)

    Vieira Lelis, F.M.; Czajkowski, R.L.; Souza, de R.M.; Ribeiro, D.H.; Wolf, van der J.M.

    2014-01-01

    In this study, colonization and disease development of axenically-grown tomato plants by Clavibacter michiganensis subsp. michiganensis (Cmm), the causative agent of bacterial wilt and canker, was investigated. For this, a spontaneous rifampicin resistant strain of Cmm was tagged with a marker that

  1. Stability and tick transmission phenotype of gfp-transformed Anaplasma marginale through a complete in vivo infection cycle

    Science.gov (United States)

    We tested the stability of transformed Anaplasma marginale during a complete in vivo infection cycle. Similar to wild-type, the transformed A. marginale established infection in cattle, a natural reservoir host, and persisted in immune competent animals. The tick infection rate was indistinguishab...

  2. Differentiation of Apical Bud Cells in a Newly Developed Apical Bud Transplantation Model Using GFP Transgenic Mice as Donor

    Science.gov (United States)

    Sakagami, Ryuji; Yoshinaga, Yasunori; Okamura, Kazuhiko

    2016-01-01

    Rodent mandibular incisors have a unique anatomical structure that allows teeth to grow throughout the lifetime of the rodent. This report presents a novel transplantation technique for studying the apical bud differentiation of rodent mandibular incisors. Incisal apical end tissue with green fluorescent protein from transgenic mouse was transplanted to wild type mice, and the development of the transplanted cells were immunohistologically observed for 12 weeks after the transplantation. Results indicate that the green fluorescent apical end tissue replaced the original tissue, and cells from the apical bud differentiated and extended toward the incisal edge direction. The immunostaining with podoplanin also showed that the characteristics of the green fluorescent tissue were identical to those of the original. The green fluorescent cells were only found in the labial side of the incisor up to 4 weeks. After 12 weeks, however, they were also found in the lingual side. Here the green fluorescent cementocyte-like cells were only present in the cementum close to the dentin surface. This study suggests that some of the cells that form the cellular cementum come from the apical tissue including the apical bud in rodent incisors. PMID:26978064

  3. Differentiation of Apical Bud Cells in a Newly Developed Apical Bud Transplantation Model Using GFP Transgenic Mice as Donor.

    Directory of Open Access Journals (Sweden)

    Naoki Maruo

    Full Text Available Rodent mandibular incisors have a unique anatomical structure that allows teeth to grow throughout the lifetime of the rodent. This report presents a novel transplantation technique for studying the apical bud differentiation of rodent mandibular incisors. Incisal apical end tissue with green fluorescent protein from transgenic mouse was transplanted to wild type mice, and the development of the transplanted cells were immunohistologically observed for 12 weeks after the transplantation. Results indicate that the green fluorescent apical end tissue replaced the original tissue, and cells from the apical bud differentiated and extended toward the incisal edge direction. The immunostaining with podoplanin also showed that the characteristics of the green fluorescent tissue were identical to those of the original. The green fluorescent cells were only found in the labial side of the incisor up to 4 weeks. After 12 weeks, however, they were also found in the lingual side. Here the green fluorescent cementocyte-like cells were only present in the cementum close to the dentin surface. This study suggests that some of the cells that form the cellular cementum come from the apical tissue including the apical bud in rodent incisors.

  4. Performance of Popular XC-Functionals for the Description of Excitation Energies in GFP-Like Chromophore Models

    DEFF Research Database (Denmark)

    List, Nanna Holmgaard; Olsen, Jógvan Magnus Haugaard; Rocha-Rinza, Tomás

    2012-01-01

    are found to give the overall best performance. The Coulomb-attenuated CAM-B3LYP functional systematically overestimates the excitation energies of the charged states; however, its error has the attractive feature of being size-independent and almost identical for the considered anionic and cationic systems...

  5. Study of the effects of MCM downregulation in vivo using a murine MCM3 GFP-Luciferase model

    OpenAIRE

    Álvarez Náñez, Silvia

    2014-01-01

    Tesis doctoral inédita leída en la Universidad Autónoma, Facultad de Ciencias, Departamento de Biología Molecular. Fecha de lectura: 11-07-2014 Defective DNA replication is linked to several forms of human disease including developmental defects and cancer. The process of genomic duplication is controlled by the frequency of activation of replication origins, which are ‘licensed’ by the assembly of the pre-replication complexes (pre-RCs) during the G1 phase of the cell cycle. T...

  6. Microbial nar-GFP cell sensors reveal oxygen limitations in highly agitated and aerated laboratory-scale fermentors

    Directory of Open Access Journals (Sweden)

    Rao Govind

    2009-01-01

    Full Text Available Abstract Background Small-scale microbial fermentations are often assumed to be homogeneous, and oxygen limitation due to inadequate micromixing is often overlooked as a potential problem. To assess the relative degree of micromixing, and hence propensity for oxygen limitation, a new cellular oxygen sensor has been developed. The oxygen responsive E. coli nitrate reductase (nar promoter was used to construct an oxygen reporter plasmid (pNar-GFPuv which allows cell-based reporting of oxygen limitation. Because there are greater than 109 cells in a fermentor, one can outfit a vessel with more than 109 sensors. Our concept was tested in high density, lab-scale (5 L, fed-batch, E. coli fermentations operated with varied mixing efficiency – one verses four impellers. Results In both cases, bioreactors were maintained identically at greater than 80% dissolved oxygen (DO during batch phase and at approximately 20% DO during fed-batch phase. Trends for glucose consumption, biomass and DO showed nearly identical behavior. However, fermentations with only one impeller showed significantly higher GFPuv expression than those with four, indicating a higher degree of fluid segregation sufficient for cellular oxygen deprivation. As the characteristic time for GFPuv expression (approx 90 min. is much larger than that for mixing (approx 10 s, increased specific fluorescence represents an averaged effect of oxygen limitation over time and by natural extension, over space. Conclusion Thus, the pNar-GFPuv plasmid enabled bioreactor-wide oxygen sensing in that bacterial cells served as individual recirculating sensors integrating their responses over space and time. We envision cell-based oxygen sensors may find utility in a wide variety of bioprocessing applications.

  7. Dose-dependent fate of GFP-E. coli in the alimentary canal of adult house flies

    Science.gov (United States)

    Adult house flies (Diptera: Muscidae; Musca domestica L.) disseminate bacteria from microbe-rich substrates to areas where humans and domesticated animals reside. Because bacterial abundance fluctuates widely across substrates, flies encounter and ingest varying amounts of bacteria. We investigated ...

  8. Evaluation and comparison of the GUS, LUC and GFP reporter system for gene expression studies in plants

    NARCIS (Netherlands)

    Ruijter, de N.C.A.; Verhees, J.A.; Leeuwen, van W.; Krol, van der A.R.

    2003-01-01

    The detailed analysis of the expression pattern of a plant gene can give important clues about its function in plant development, cell differentiation and defence reactions. Gene expression studies have been greatly facilitated by the employment of proteins like beta-glucuronidase (GUS), green fluor

  9. Structural interaction between GFP-labeled diazotrophic endophytic bacterium Herbaspirillum seropedicae RAM10 and pineapple plantlets 'Vitória'

    Directory of Open Access Journals (Sweden)

    Lílian Estrela Borges Baldotto

    2011-03-01

    Full Text Available The events involved in the structural interaction between the diazotrophic endophytic bacterium Herbaspirillum seropedicae, strain RAM10, labeled with green fluorescent protein, and pineapple plantlets 'Vitória' were evaluated by means of bright-field and fluorescence microscopy, combined with scanning electron microscopy for 28 days after inoculation. After 6 hours of inoculation, H. seropedicae was already adhered to the roots, colonizing mainly root hair surface and bases, followed by epidermal cell wall junctions. Bacteria adherence in the initial periods occurred mainly in the form of solitary cells and small aggregates with pleomorphic cells. Bacteria infection of root tissue occurred through the cavities caused by the disruption of epidermal cells during the emergence of lateral roots and the endophytic establishment by the colonization of intercellular spaces of the cortical parenchyma. Moreover, within 1 day after inoculation the bacteria were colonizing the shoots. In this region, the preferred sites of epiphytic colonization were epidermal cell wall junctions, peltate scutiform trichomes and non-glandular trichomes. Subsequently, the bacteria occupied the outer periclinal walls of epidermal cells and stomata. The penetration into the shoot occurred passively through stoma aperture followed by the endophytic establishment on the substomatal chambers and spread to the intercellular spaces of spongy chlorenchyma. After 21 days of inoculation, bacterial biofilm were seen at the root hair base and on epidermal cell wall surface of root and leaf, also confirming the epiphytic nature of H. seropedicae.

  10. The uptake of Texas Red-BSA in the excretory system of schistosomes and its colocalisation with ER60 promoter-induced GFP in transiently transformed adult males.

    Science.gov (United States)

    Wippersteg, Volker; Ribeiro, Fabio; Liedtke, Stefanie; Kusel, John R; Grevelding, Christoph G

    2003-09-30

    The excretory system of schistosomes has focused some attention during the last years since accumulating evidence suggests that it plays an important role in the host-parasite interaction. Signalling molecules such as phosphatases, but also proteases have been localised in the excretory system. To some extent, however, localisation studies are limited by the fact that sections of fixed specimens are used. In this study, we tested the fluorescent molecules FITC-dextran and Texas Red-BSA for their ability to enter the excretory system of living Schistosoma mansoni males. It is demonstrated that the dyes selectively stain the excretory tubules which are widely distributed along the worm body. This finding was used to investigate whether the staining of worms with Texas Red-BSA can help to localise transgene activity in worms which were transiently transformed by particle bombardment. A vector was used for transformation which contained the green fluorescent protein gene, under the control of the regulatory elements of the cysteine protease ER60 gene. After transformation and staining, confocal laser scanning microscopy revealed that ER60-induced green fluorescent protein activity colocalises with Texas Red-BSA in the excretory tubules. The results suggest a role for ER60 during the host-parasite interaction. Furthermore, the colocalisation approach introduced here opens further perspectives to characterise gene-expression profiles in this parasite.

  11. Characterization of functionally active interleukin-18/eGFP fusion protein expression during cell cycle phases in recombinant chicken DF1 Cells.

    Science.gov (United States)

    Wu, Hsing Chieh; Chen, Yu San; Shien, Jui Hung; Shen, Pin Chun; Lee, Long Huw

    2016-05-01

    The dependence of foreign gene expression on cell cycle phases in mammalian cells has been described. In this study, a DF1/chIL-18a cell line that stably expresses the fusion protein chIL-18 was constructed and the enhanced green fluorescence protein connected through a (G4 S)3 linker sequence investigated the relationship between cell cycle phases and fusion protein production. DF1/chIL-18a cells (1 × 10(5) ) were inoculated in 60-mm culture dishes containing 5 mL of media to achieve 50%-60% confluence and were cultured in the presence of the cycle-specific inhibitors 10058-F4, aphidicolin, and colchicine for 24 and 48 h. The percentage of cell density and mean fluorescence intensity in each cell cycle phase were assessed using flow cytometry. The inhibitors effectively arrested cell growth. The fusion protein production rate was higher in the S phase than in the G0/G1 and G2/M phases. When cell cycle progression was blocked in the G0/G1, S, and G2/M phases by the addition of 10058-F4, aphidicolin, and colchicine, respectively, the aphidicolin-induced single cells showed higher fusion protein levels than did the 10058-F4- or colchicine-induced phase cells and the uninduced control cells. Although the cells did not proliferate after the drug additions, the amount of total fusion protein accumulated in aphidicolin-treated cells was similar to that in the untreated cultures. Fusion protein is biologically active because it induces IFN-γ production in splenocyte cultures of chicken. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:581-591, 2016.

  12. Tracking contamination through ground beef production and identifying points of recontamination using a novel green fluorescent protein (GFP) expressing, E. coli O103, non-pathogenic surrogate

    Science.gov (United States)

    Introduction: Commonly, ground beef processors conduct studies to model contaminant flow through their production systems using surrogate organisms. Typical surrogate organisms may not behave as Escherichia coli O157:H7 during grinding and are not easy to detect at very low levels. Purpose: Develop...

  13. GUS and GFP transformation of the biocontrol strain Clonostachys rosea IK726 and the use of these marker genes in ecological studies

    DEFF Research Database (Denmark)

    Lübeck, M.; Knudsen, I.M.B.; Jensen, B.;

    2002-01-01

    directly in soil, vermiculite, on carrot seed and roots, and on barley leaves. It was shown that C. rosea can thrive in very different niches. Conidia germination, colonization and conidiogenesis were demonstrated in vivo in all four environments. This is the first report on transformation of Clonostachys...

  14. Quantitative evaluation of morpholino-mediated protein knockdown of GFP, MSX1, and PAX7 during tail regeneration in Ambystoma mexicanum.

    Science.gov (United States)

    Schnapp, Esther; Tanaka, Elly M; Tamaka, Elly M

    2005-01-01

    Vertebrate regeneration is a fascinating but poorly understood biological phenomena. Urodele amphibians such as Ambystoma mexicanum (the axolotl) can functionally regenerate complex body structures such as the limb and tail, including the spinal cord, throughout life. So far, molecular studies on regeneration have been limited due to the paucity of tools for knocking-down gene and protein function. In this article, we quantitatively assessed the ability of morpholinos to specifically down-regulate protein expression in both cultured urodele cells and in vivo. We focused on the down-regulation of green fluorescent protein and two axolotl proteins, MSX1 and PAX7. Our data show that the expression of these proteins can be efficiently reduced by morpholinos. MSX1 has been hypothesized to be involved in muscle dedifferentiation based on experiments using cultured myotubes. Our studies in in vivo muscle fibers so far have shown no influence of overexpressing or down-regulating MSX1 on the dedifferentiation process.

  15. A flow cytometry-optimized assay using an SOS-green fluorescent protein (SOS-GFP) whole-cell biosensor for the detection of genotoxins in complex environments

    DEFF Research Database (Denmark)

    Norman, Anders; Hansen, Lars H.; Sørensen, Søren Johannes

    2006-01-01

    Whole-cell biosensors have become popular tools for detection of ecotoxic compounds in environmental samples. We have developed an assay optimized for flow cytometry with detection of genotoxic compounds in mind. The assay features extended pre-incubation and a cell density of only 106-107 cells/......-contaminated soil particles when using flow cytometry, and induction of the biosensor by mitomycin C was detectable at concentrations as low as 2.5 ng/g of soil....

  16. pBaSysBioll : an integrative plasmid generating gfp transcriptional fusions for high-throughput analysis of gene expression in Bacillus subtilis

    NARCIS (Netherlands)

    Botella, Eric; Fogg, Mark; Jules, Matthieu; Piersma, Sjouke; Doherty, Geoff; Hansen, Annette; Denham, Emma. L.; Le Chat, Ludovic; Veiga, Patrick; Bailey, Kirra; Lewis, Peter J.; van Dijl, Jan Maarten; Aymerich, Stephane; Wilkinson, Anthony J.; Devine, Kevin M.

    Plasmid pBaSysBioll was constructed for high-throughput analysis of gene expression in Bacillus subtilis. It is an integrative plasmid with a ligation-independent cloning (LIC) site, allowing the generation of transcriptional gfpmut3 fusions with desired promoters. Integration is by a Campbell-type

  17. A native promoter and inclusion of an intron is necessary for efficient expression of GFP or mRFP in Armillaria mellea

    Science.gov (United States)

    Armillaria mellea is a significant pathogen that causes Armillaria root disease on numerous hosts in forests, gardens and agricultural environments worldwide. Using a yeast-adapted pCAMBIA0380 Agrobacterium vector, we have constructed a series of vectors for transformation of A. mellea, assembled u...

  18. pBaSysBioll : an integrative plasmid generating gfp transcriptional fusions for high-throughput analysis of gene expression in Bacillus subtilis

    NARCIS (Netherlands)

    Botella, Eric; Fogg, Mark; Jules, Matthieu; Piersma, Sjouke; Doherty, Geoff; Hansen, Annette; Denham, Emma. L.; Le Chat, Ludovic; Veiga, Patrick; Bailey, Kirra; Lewis, Peter J.; van Dijl, Jan Maarten; Aymerich, Stephane; Wilkinson, Anthony J.; Devine, Kevin M.

    2010-01-01

    Plasmid pBaSysBioll was constructed for high-throughput analysis of gene expression in Bacillus subtilis. It is an integrative plasmid with a ligation-independent cloning (LIC) site, allowing the generation of transcriptional gfpmut3 fusions with desired promoters. Integration is by a Campbell-type

  19. Procurement and persistence of GFP-expressing Escherichia coli and Salmonella Typhimurium in male and female house flies exposed to cattle manure

    Science.gov (United States)

    Introduction: Adult house flies, Musca domestica L., are associated with animal manure and other microbe-rich substrates. Consequently, both sexes can acquire and potentially disseminate pathogenic bacteria to surrounding environments, including residential areas, via contaminated body parts and/or ...

  20. Adenovirus replication-competent vectors (KD1, KD3) complement the cytotoxicity and transgene expression from replication-defective vectors (Ad-GFP, Ad-Luc).

    Science.gov (United States)

    Habib, Nagy A; Mitry, Ragai; Seth, Prem; Kuppuswamy, Mohan; Doronin, Konstantin; Toth, Karoly; Krajcsi, Peter; Tollefson, Ann E; Wold, William S M

    2002-08-01

    The successful clinical application of adenovirus (Ad) in cancer control has been of limited success because of the current inability to infect the majority of cancer cells with a large amount of vector. In this study, we show that when human lung tumors growing in immunodeficient nude mice were coinfected with a replication-defective (RD) Ad vector expressing green fluorescent protein and a replication-competent (RC) Ad vector named KD3, KD3 enhanced the expression of green fluorescent protein throughout the tumor. Also, KD3 and another RC vector named KD1 complemented the expression of luciferase from a RD vector in a human liver tumor xenotransplant in nude mice. Altogether, these results suggest that the combination of a RD vector with a RC vector might be a more effective treatment for cancer than either vector alone due to more widespread dissemination of the virus.

  1. Development and application of a green fluorescent protein (GFP) expressing E. coli O103 surrogate for tracking contamination through grinding and identifying persistent points of contamination

    Science.gov (United States)

    Objective: To 1.) develop and validate an easily trackable E. coli O157:H7/non-O157 STEC surrogate that can be detected to the same level of sensitivity as E. coli O157:H7; and 2.) apply the trackable surrogate to model contamination passage through grinding and identify points where contamination ...

  2. Archive of digital chirp subbottom profile data collected during USGS Cruise 13GFP01, Brownlee Dam and Hells Canyon Reservoir, Idaho and Oregon, 2013

    Science.gov (United States)

    Forde, Arnell S.; Dadisman, Shawn V.; Flocks, James G.; Fosness, Ryan L.; Welcker, Chris; Kelso, Kyle W.

    2014-01-01

    From March 16 - 31, 2013, the U.S. Geological Survey in cooperation with the Idaho Power Company conducted a geophysical survey to investigate sediment deposits and long-term sediment transport within the Snake River from Brownlee Dam to Hells Canyon Reservoir, along the Idaho and Oregon border; this effort will help the USGS to better understand geologic processes. This report serves as an archive of unprocessed digital chirp subbottom data, trackline maps, navigation files, Geographic Information System (GIS) files, Field Activity Collection System (FACS) logs, and formal Federal Geographic Data Committee (FGDC) metadata. Gained (showing a relative increase in signal amplitude) digital images of the seismic profiles are also provided. Refer to the Acronyms page for expansions of acronyms and abbreviations used in this report.

  3. GFP内核加速LAN/SAN协议在SONET中的传输%GFP Core Speeds up the Transporting of LAN/SAN Protocol in SONET

    Institute of Scientific and Technical Information of China (English)

    Tom Fischaber; Krista Marks; Hamish Fallside

    2004-01-01

    在电信行业中,SONET网络无处不在,被广泛应用于语音和数据传输。目前的标准协议主要针对传输层,如针对语音和数据的ATM协议以及针对数据传输的HDLC或PPP协议。然而,因为这些协议都不是专门针对通过SONET/SDH网络进行数据传输而开发的,所以都会引起带宽效率的降低。

  4. A fungal biofilm reactor based on metal structured packing improves the quality of a Gla::GFP fusion protein produced by Aspergillus oryzae

    NARCIS (Netherlands)

    Zune, Q.; Delepierre, A.; Gofflot, S.; Bauwens, J.; Twizere, J.C.; Punt, P.J.; Francis, F.; Toye, D.; Bawin, T.; Delvigne, F.

    2015-01-01

    Fungal biofilm is known to promote the excretion of secondary metabolites in accordance with solid-staterelated physiological mechanisms. This work is based on the comparative analysis of classical submerged fermentation with a fungal biofilmreactor for the production of a Gla::green fluorescent pro

  5. Comparative analysis of twin-arginine (Tat)-dependent protein secretion of a heterologous model protein (GFP) in three different Gram-positive bacteria

    NARCIS (Netherlands)

    Meissner, Daniel; Vollstedt, Angela; van Dijl, Jan Maarten; Freudl, Roland

    2007-01-01

    In contrast to the general protein secretion (Sec) system, the twin-arginine translocation (Tat) export pathway allows the translocation of proteins across the bacterial plasma membrane in a fully folded conformation. Due to this feature, the Tat pathway provides an attractive alternative to the sec

  6. 转KAP6.1-GFP-蜘蛛拖丝蛋白基因核心序列4S绵羊成纤维细胞株的筛选%Filtration of Transgenic Sheep Skin Fibroblasts with KAP6.1-GFP-polymerized Spider Dragline Silk Protein Gene(4S)

    Institute of Scientific and Technical Information of China (English)

    王春生; 原璐; 宁方勇; 吴治昊; 朴善花; 安铁洙

    2011-01-01

    [目的]通过体细胞核移植为获得皮肤特异表达蜘蛛拖丝蛋白的绵羊莫定基础.[方法]将pcDNA3.1和带有角蛋白结合蛋白启动子质粒pGM-T-KAP6.1分别用Bg1 Ⅱ和Hin d Ⅲ双酶切后连接,再与蜘蛛拖丝蛋白基因核心序列4S连接,最后通过酶切与pIRES2-EGFP质粒连接后构建真核表达载体pIRES2-EGFP-4S;将此载体线性化后,采用脂质体法转染绵羊皮肤成纤维细胞,通过G418筛选获得转基因阳性细胞.[结果]筛选得到转pIRES2-EGFP-4S的阳性细胞.对阳性细胞经体外培养后的检测显示:(1)细胞形态(长梭形)、细胞生长曲线(呈S形)、群体倍增时间(随培养时间增加逐渐缩短)和细胞接种率(细胞贴壁率及存活率在24 h内逐渐升高,并达到最高值125%)等均具有正常绵羊成纤维细胞的生物学特征;(2)阳性细胞经冷冻复苏后具有与新鲜阳性细胞相似的生物学特征;(3)PCR检测结果显示,pIRES2-EGFP-4S在阳性细胞的基因组中整合.[结论]获得具有在绵羊皮肤特异表达,且便于检测的转蜘蛛拖丝蛋白4S的绵羊成纤维细胞株.%[Objective] This study aims to establish transgenic sheep fibroblast cell line and lay a foundation for transgenic sheep with expression spider dragline silk protein gene in hair follicle by nuclear transplantation. [Method] pcDNA3.1 and pGM-T-KAP6.1(hair follicle-specific promoter) were digested by 5g/Ⅱand Hind Ⅲ, and linked each other. The recombinant plasmid was linked with spider dragline silk protein gene and then linked with pIRES2-EGFP by a series of molecular methods. The eukaryotic expression vector pIRES2-EGFP-4S was constructed. Sheep fibroblasts were transfected with the plasmid by cationic liposome method and G418 was used to filtrate them. After identified, transgenic cell line with spider dragline silk protein gene was established. [Result] The G418 positive cells were detected in vitro. The results showed that cellular morphology was similar with normal fibroblast, cell growth curve was "S" shape, population doubling time (PDT) shorten gradually along with culture time increase, plating efficiency was gradually increasing in 24h. These biological analyses showed the transgenic cells were similar with normal sheep fibroblast. Biological characters of the transgenic cells after freezing-thawing were similar with fresh sheep fibroblast. The PCR result showed that the vector constructed was integrated into sheep genome. [Conclusion] The transgenic cells with polymerized spider dragline silk protein gene were filtrated, and thus laid a foundation for the transgenic sheep with expression spider dragline silk protein in hair follicle.

  7. Experiment list: SRX023655 [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available noma cell line || cell line=HeLa Kyoto cell line || sample type=Antibody GFP (custom GFP antibody generously...ibody=anti-GFP || antibody manufacturer=custom GFP antibody generously provided by Ina Poser || transfection

  8. In vivo measurement of cytosolic and mitochondrial pH using a pH-sensitive GFP derivative in Saccharomyces cerevisiae reveals a relation between intracellular pH and growth

    National Research Council Canada - National Science Library

    Orij, Rick; Postmus, Jarne; Ter Beek, Alex; Brul, Stanley; Smits, Gertien J

    2009-01-01

    ...), University of Amsterdam, The Netherlands Correspondence Gertien J. Smits g.j.smits{at}uva.nl The specific pH values of cellular compartments affect virtually all biochemical processes, including enzyme activity, protein folding and redox state...

  9. 生防菌株336x 在小麦内部的定殖研究%Endophytic Colonization of GFP-tagged Biocontrol Bacterium Strain 336x in Wheat

    Institute of Scientific and Technical Information of China (English)

    王淼; 张颖; 柴沆镇; 王刚

    2013-01-01

    变形斑沙雷氏菌(Serratia p roteamaculans )336x是一株对小麦全蚀病具有生防作用的小麦内生细菌。为研究336 x在小麦内部的定殖及分布,将336 x基因组酶切片段与携带绿色荧光蛋白基因(g f p)的质粒pAD123进行连接,筛选产生荧光的质粒并转化336x菌株,获得336x的荧光标记菌株336x gfpa。对比336x gfpa与野生型菌株在小麦中的定殖能力及对小麦全蚀病的生防能力,发现二者无显著差异;荧光显微镜观察结果表明,336x gfpa主要定殖于小麦根部细胞间隙和维管组织。%Serratia proteamaculans strain 336x isolated from wheat roots is an endophytic bacte-rium and has biological control activity against take-all of wheat induced by Gaeumannomyces graminis var .tritici .To elucidate colonization pattern of 336x in wheat ,the genomic DNA frag-ments of 336x were inserted into pAD123 to construct pAD123-336x ,in which the gf p gene was expressed under the control of 336x gene promoter .The plasmid pAD123-336x was transferred in-to 336x wild type strain by electroporation ,and one mutant designated as 336x-gfpa was acquired . Colonization study and biocontrol assay revealed that 336x-gfpa had comparatively equal biocon-trol activity and colonization ability to 336x .Observation under fluorescent microscope revealed that 336x-gfpa was mainly colonized in intercellular space and vascular tissue of wheat root .

  10. Is salamander hindlimb regeneration similar to that of the forelimb? Anatomical and morphogenetic analysis of hindlimb muscle regeneration in GFP-transgenic axolotls as a basis for regenerative and developmental studies

    Science.gov (United States)

    Diogo, R; Murawala, P; Tanaka, E M

    2014-01-01

    The axolotl Ambystoma mexicanum is one of the most used model organisms in developmental and regenerative studies because it is commonly said that it can reconstitute a normal and fully functional forelimb/hindlimb after amputation. However, there is not a publication that has described in detail the regeneration of the axolotl hindlimb muscles. Here we describe and illustrate, for the first time, the regeneration of the thigh, leg and foot muscles in transgenic axolotls that express green fluorescent protein in muscle fibers and compare our results with data obtained by us and by other authors about axolotl forelimb regeneration and about fore-and hindlimb ontogeny in axolotls, frogs and other tetrapods. Our observations and comparisons point out that: (1) there are no muscle anomalies in any regenerated axolotl hindlimbs, in clear contrast to our previous study of axolotl forelimb regeneration, where we found muscle anomalies in 43% of the regenerated forelimbs; (2) during axolotl hindlimb regeneration there is a proximo-distal and a tibio-fibular morphogenetic gradient in the order of muscle regeneration and differentiation, but not a ventro-dorsal gradient, whereas our previous studies showed that in axolotl forelimb muscle regeneration there are proximo-distal, radio-ulnar and ventro-dorsal morphogenetic gradients. We discuss the broader implications of these observations for regenerative, evolutionary, developmental and morphogenetic studies. PMID:24325444

  11. Is salamander hindlimb regeneration similar to that of the forelimb? Anatomical and morphogenetic analysis of hindlimb muscle regeneration in GFP-transgenic axolotls as a basis for regenerative and developmental studies.

    Science.gov (United States)

    Diogo, R; Murawala, P; Tanaka, E M

    2014-04-01

    The axolotl Ambystoma mexicanum is one of the most used model organisms in developmental and regenerative studies because it is commonly said that it can reconstitute a normal and fully functional forelimb/hindlimb after amputation. However, there is not a publication that has described in detail the regeneration of the axolotl hindlimb muscles. Here we describe and illustrate, for the first time, the regeneration of the thigh, leg and foot muscles in transgenic axolotls that express green fluorescent protein in muscle fibers and compare our results with data obtained by us and by other authors about axolotl forelimb regeneration and about fore- and hindlimb ontogeny in axolotls, frogs and other tetrapods. Our observations and comparisons point out that: (1) there are no muscle anomalies in any regenerated axolotl hindlimbs, in clear contrast to our previous study of axolotl forelimb regeneration, where we found muscle anomalies in 43% of the regenerated forelimbs; (2) during axolotl hindlimb regeneration there is a proximo-distal and a tibio-fibular morphogenetic gradient in the order of muscle regeneration and differentiation, but not a ventro-dorsal gradient, whereas our previous studies showed that in axolotl forelimb muscle regeneration there are proximo-distal, radio-ulnar and ventro-dorsal morphogenetic gradients. We discuss the broader implications of these observations for regenerative, evolutionary, developmental and morphogenetic studies. © 2013 Anatomical Society.

  12. Gateway技术构建转基因重组质粒pRP.EX3d-EF1A-LRP16-His-IRES-eGFP

    Institute of Scientific and Technical Information of China (English)

    柏苗苗; 王春萌; 伍志强; 梅倩; 李小雷; 李祥; 赵亚力; 韩为东

    2014-01-01

    目的:构建转基因重组质粒pRP.EX3d-EF1A-LRP16-His-IRES-eGFP,为转基因鼠的建立奠定基础。方法利用重叠PCR技术扩增attB1-LRP16-His-attB2,经BP反应,将LRP16基因插入到载体pDown上,pUp-EF1A、pDown-LRP16-His、pTail-IRES-eGFP和PRP.Des3d经LR反应,将LRP16转移到pRP.EX3d上,转化Stbl3细胞,用氨苄西林进行抗性筛选,经PCR鉴定后将阳性克隆送测序。结果测序及酶切结果验证获得正确的pRP.EX3d-EF1A-LRP16-His-IRES-eGFP重组质粒。结论成功构建pRP.EX3d-EF1A-LRP16-His-IRES-eGFP重组质粒,可用于下一步LRP16转基因小鼠的构建。

  13. Robust expression of the human neonatal Fc receptor in a truncated soluble form and as a full-length membrane-bound protein in fusion with eGFP.

    Directory of Open Access Journals (Sweden)

    Johan Seijsing

    Full Text Available Studies on the neonatal Fc receptor (FcRn have revealed a multitude of important functions in mammals, including protection of IgG and serum albumin (SA from lysosomal degradation. The pharmacokinetic behavior of therapeutic antibodies, IgG-Fc- and SA-containing drugs is therefore influenced by their interaction with FcRn. Pre-clinical development of such drugs is facilitated if their interaction with FcRn can be studied in vitro. For this reason we have developed a robust system for production of the soluble extracellular domain of human FcRn as well as the full-length receptor as fusion to green fluorescent protein, taking advantage of a lentivirus-based gene delivery system where stable over-expressing cells are easily and rapidly generated. Production of the extracellular domain in multiple-layered culture flasks, followed by affinity purification using immobilized IgG, resulted in capture of milligram amounts of soluble receptor per liter cell culture with retained IgG binding. The receptor was further characterized by SDS-PAGE, western blotting, circular dichroism spectroscopy, ELISA, surface plasmon resonance and a temperature stability assay showing a functional and stable protein of high purity. The full-length receptor was found to be successfully over-expressed in a membrane-bound form with retained pH-dependent IgG- and SA-binding.

  14. 根癌农杆菌介导绿色荧光蛋白基因转化印度酸桔的研究%The Transformation of gfp in Cleopatra (Citrus reticulata ) Mediated by Agrobacterium tumefaciens

    Institute of Scientific and Technical Information of China (English)

    石玮; 李东栋; 邓秀新; 伊华林

    2002-01-01

    通过根癌农杆菌介导将绿色荧光蛋白基因转入印度酸桔的胚性愈伤组织中,经潮霉素筛选,获得抗性愈伤组织,并再生植株.对这些植株进行GUS染色、PCR分析、绿色荧光检测和Sourthem杂交验证,结果表明绿色荧光蛋白已经在转基因植株中表达.

  15. Experiment list: SRX023660 [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available a cell line || cell line=HeLa Kyoto cell line || sample type=Antibody GFP (custom GFP antibody generously pr...y=anti-GFP || antibody manufacturer=custom GFP from Ina Poser || transfection=N-PAC-GFP BAC http://dbarchive

  16. Fertility and pregnancy-associated ß-cell proliferation in mice deficient in proglucagon-derived peptides.

    Directory of Open Access Journals (Sweden)

    Chisato Sugiyama

    Full Text Available Proglucagon, which is encoded by the glucagon gene (Gcg, is the precursor of several peptide hormones, including glucagon and glucagon-like peptide 1 (GLP-1. Whereas glucagon stimulates hepatic glycogenolysis and gluconeogenesis, GLP-1 stimulates insulin secretion to lower blood glucose and also supports ß-cell proliferation and protection from apoptotic stimuli. Pregnancy is a strong inducer of change in islet function, however the roles of proglucagon-derived peptides in pregnancy are only partially understood. In the present study, we analyzed fertility and pregnancy-associated changes in homozygous glucagon-green fluorescent protein (gfp knock-in mice (Gcg(gfp/gfp, which lack all the peptides derived from proglucagon. Female Gcg(gfp/gfp mice could deliver and raise Gcg(gfp/gfp pups to weaning and Gcg(gfp/gfp pups from Gcg(gfp/gfp dams were viable and fertile. Pregnancy induced ß-cell proliferation in Gcg(gfp/gfp mice as well as in control mice. However, serum insulin levels in pregnant Gcg(gfp/gfp females were lower than those in control pregnant females under ad libitum feeding, and blood glucose levels in pregnant Gcg(gfp/gfp females were higher after gestational day 12. Gcg(gfp/gfp females showed a decreased pregnancy rate and smaller litter size. The rate of successful breeding was significantly lower in Gcg(gfp/gfp females and was not improved by experience of breeding. Taken together, proglucagon-derived peptides are not required for pregnancy-associated ß-cell proliferation, however, are required for regulation of blood glucose levels and normal reproductive capacity. Gcg(gfp/gfp mice may serve as a novel model to analyze the effect of mild hyperglycemia during late gestational periods.

  17. Recombination-stable multimeric green fluorescent protein for characterization of weak promoter outputs inSaccharomyces cerevisiae

    DEFF Research Database (Denmark)

    Rugbjerg, Peter; Knuf, Christoph; Förster, Jochen;

    2015-01-01

    functions well in translational fusions, the use of tandem GFPs to amplify fluorescence signals is currently avoided in Saccharomyces cerevisiae and many other microorganisms due to the risk of loop-out by direct-repeat recombination. We increased GFP fluorescence by translationally fusing three different...... GFP variants, yeast-enhanced GFP, GFP+ and superfolder GFP to yield a sequence-diverged triple GFP molecule 3vGFP with 74–84% internal repeat identity. Unlike a single GFP, the brightness of 3vGFP allowed characterization of a weak promoter in S. cerevisiae. Utilizing 3vGFP, we further engineered...... a less leaky Cu2+-inducible promoter based on CUP1. The basal expression level of the new promoter was approx. 61% below the wild-type CUP1 promoter, thus expanding the absolute range of Cu2+-based gene control. The stability of 3vGFP towards direct-repeat recombination was assayed in S. cerevisiae...

  18. Localization and Differential Expression of the Krüppel-Associated Box Zinc Finger Proteins 1 and 54 in Early Mouse Development

    DEFF Research Database (Denmark)

    Albertsen, Maria; Teperek, Marta; Elholm, Grethe;

    2010-01-01

    -fused reporter gene into zygotes demonstrated the intracellular distribution of ZFP1-green fluorescent protein (GFP) and ZFP54-GFP colocalized with a DNA marker in the two-cell embryo. The KRAB domain was essential to colocalize with DNA, and deletion of the KRAB domain in ZFP1-GFP and ZFP54-GFP localized...

  19. Intracellular distribution of cowpea mosaic virus movement protein as visualised by green fluorescent protein fusions

    NARCIS (Netherlands)

    Gopinath, K.; Bertens, P.; Pouwels, J.; Marks, H.; Lent, van J.W.M.; Wellink, J.E.; Kammen, van A.

    2003-01-01

    Cowpea mosaic virus (CPMV) derivatives expressing movement protein (MP) green fluorescent protein (GFP) fusions (MP:GFP) were used to study the intracellular targeting and localization of the MP in cowpea protoplasts and plants. In protoplasts, a virus coding for a wild type MP:GFP (MPfGFP) induced

  20. Recombination-stable multimeric green fluorescent protein for characterization of weak promoter outputs in Saccharomyces cerevisiae

    DEFF Research Database (Denmark)

    Rugbjerg, Peter; Knuf, Christoph; Förster, Jochen

    2015-01-01

    Green fluorescent proteins (GFPs) are widely used for visualization of proteins to track localization and expression dynamics. However, phenotypically important processes can operate at too low expression levels for routine detection, i.e. be overshadowed by autofluorescence noise. While GFP...... GFP variants, yeast-enhanced GFP, GFP+ and superfolder GFP to yield a sequence-diverged triple GFP molecule 3vGFP with 74–84% internal repeat identity. Unlike a single GFP, the brightness of 3vGFP allowed characterization of a weak promoter in S. cerevisiae. Utilizing 3vGFP, we further engineered...... cultured for 25 generations under strong and slightly toxic expression after which only limited reduction in fluorescence was detectable. Such non-recombinogenic GFPs can help quantify intracellular responses operating a low copy number in recombination-prone organisms....

  1. Recombination-stable multimeric green fluorescent protein for characterization of weak promoter outputs in Saccharomyces cerevisiae

    DEFF Research Database (Denmark)

    Rugbjerg, Peter; Knuf, Christoph; Förster, Jochen;

    2015-01-01

    GFP variants, yeast-enhanced GFP, GFP+ and superfolder GFP to yield a sequence-diverged triple GFP molecule 3vGFP with 74–84% internal repeat identity. Unlike a single GFP, the brightness of 3vGFP allowed characterization of a weak promoter in S. cerevisiae. Utilizing 3vGFP, we further engineered...... a less leaky Cu2+-inducible promoter based on CUP1. The basal expression level of the new promoter was approx. 61% below the wild-type CUP1 promoter, thus expanding the absolute range of Cu2+-based gene control. The stability of 3vGFP towards direct-repeat recombination was assayed in S. cerevisiae...

  2. A new cell-based assay to evaluate myogenesis in mouse myoblast C2C12 cells

    Energy Technology Data Exchange (ETDEWEB)

    Kodaka, Manami [Department of Medical Biochemistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo (Japan); Yang, Zeyu [Department of Medical Biochemistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo (Japan); Department of Ultrasound, Shengjing Hospital of China Medical University, Shenyang (China); Nakagawa, Kentaro; Maruyama, Junichi [Department of Medical Biochemistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo (Japan); Xu, Xiaoyin [Department of Medical Biochemistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo (Japan); Department of Breast Surgery, The Second Affiliated Hospital of Wenzhou Medical University, Wenzhou (China); Sarkar, Aradhan; Ichimura, Ayana [Department of Medical Biochemistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo (Japan); Nasu, Yusuke [Department of Breast Surgery, The Second Affiliated Hospital of Wenzhou Medical University, Wenzhou (China); Ozawa, Takeaki [Department of Chemistry, School of Science, The University of Tokyo, Tokyo (Japan); Iwasa, Hiroaki [Department of Medical Biochemistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo (Japan); Ishigami-Yuasa, Mari [Chemical Biology Screening Center, Tokyo Medical and Dental University, Tokyo (Japan); Ito, Shigeru [Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University, Tokyo (Japan); Kagechika, Hiroyuki [Chemical Biology Screening Center, Tokyo Medical and Dental University, Tokyo (Japan); Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University, Tokyo (Japan); and others

    2015-08-15

    The development of the efficient screening system of detecting compounds that promote myogenesis and prevent muscle atrophy is important. Mouse C2C12 cells are widely used to evaluate myogenesis but the procedures of the assay are not simple and the quantification is not easy. We established C2C12 cells expressing the N-terminal green fluorescence protein (GFP) and the C-terminal GFP (GFP1–10 and GFP11 cells). GFP1–10 and GFP11 cells do not exhibit GFP signals until they are fused. The signal intensity correlates with the expression of myogenic markers and myofusion. Myogenesis-promoting reagents, such as insulin-like growth factor-1 (IGF1) and β-guanidinopropionic acid (GPA), enhance the signals, whereas the poly-caspase inhibitor, z-VAD-FMK, suppresses it. GFP signals are observed when myotubes formed by GFP1–10 cells are fused with single nuclear GFP11 cells, and enhanced by IGF1, GPA, and IBS008738, a recently-reported myogenesis-promoting reagent. Fusion between myotubes formed by GFP1–10 and GFP11 cells is associated with the appearance of GFP signals. IGF1 and GPA augment these signals, whereas NSC23766, Rac inhibitor, decreases them. The conditioned medium of cancer cells suppresses GFP signals during myogenesis and reduces the width of GFP-positive myotubes after differentiation. Thus the novel split GFP-based assay will provide the useful method for the study of myogenesis, myofusion, and atrophy. - Highlights: • C2C12 cells expressing split GFP proteins show GFP signals when mix-cultured. • The GFP signals correlate with myogenesis and myofusion. • The GFP signals attenuate under the condition that muscle atrophy is induced.

  3. 结合GAL4/UAS系统与CyO-GFP平衡子获取表达RNA干扰序列果蝇幼虫并有效干扰Tis11表达%Combining GAL4/UAS System and CyO-GFP Balancer to Obtain RNA Interference Sequences-expressing Drosophila Larvae in Which Tis11 is Down-regulated

    Institute of Scientific and Technical Information of China (English)

    张梅超; 刘勇; 韦有恒; 马维骏

    2014-01-01

    TIS11是转录后调控因子TTP在果蝇中的同源物,在果蝇幼虫免疫、发育和代谢等多种生理过程中都发挥重要作用.为研究TIS11的功能,需要利用GAL4/UAS系统获得整体高干扰效率的Tis11 RNAi果蝇幼虫.为平衡GAL4转基因果蝇高活性启动子的致死效应,需要使用带有成蝇卷翅标记CyO的第二染色体的平衡子,但CyO标记在幼虫中无可见表型,因此无法区分杂交幼虫的基因型.为解决这一问题,引入了带有CyO-GFP标记的平衡子.携带CyO-GFP平衡子的G-Actin果蝇与携带Tis11 RNAi序列的101765果蝇杂交,杂交幼虫可以通过GFP标记进行区分,剔除带有CyO-GFP平衡子的幼虫,从而挑选出表达Tis11 RNAi序列的幼虫,最后经real-time PCR检测所得幼虫具有整体高干扰效率.

  4. Three Landmarks During the Research of the Green Fluorescent Protein (GFP): A Brief Introduction to the 2008 Nobel Prize in Chemistry%绿色荧光蛋白研究的三个里程碑——2008年诺贝尔化学奖简介

    Institute of Scientific and Technical Information of China (English)

    崔志芳; 邹玉红; 季爱云

    2008-01-01

    2008年10月8日,美国科学家下村修、马丁·查尔非以及钱永健因为在绿色荧光蛋白的发现以及改造方面的突出成就而获得2008年度诺贝尔化学奖.笔者拟对绿色荧光蛋白的研究历程以及应用领域做一些粗浅介绍.

  5. Preparation of North American Type II PRRSV Infectious Clone Expressing Green Fluorescent Protein

    Directory of Open Access Journals (Sweden)

    Liyue Wang

    2014-01-01

    Full Text Available Porcine reproductive and respiratory syndrome virus (PRRSV is still one of the most important infectious diseases threatening the swine industry. To construct North American type II PRRSV infectious clone containing green fluorescent protein (GFP gene, we amplify gfp gene, flanked by PRRSV Nsp2 gene fragments upstream and downstream, using overlap PCR method from pcDNA-EF1-GFP plasmid and FL12 plasmid containing PRRSV infectious genome as the templates. The Nsp2 fragment-flanked gfp gene was inserted into Nsp2 gene of the FL12 plasmid by Spe I and Xho I sites to generate PRRSV infectious recombinant plasmid (FL12-GFP containing gfp gene. The recombinant PRRSV expressing GFP (PRRSV-GFP was rescued in baby hamster kidney-21 (BHK-21 cells by transfecting PRRSV mRNA synthesized in vitro and amplified in Marc-145 cells. The PRRSV-GFP infectivity and replication capacity were identified. Results showed that, by adopting overlap PCR strategy, the gfp gene was successfully inserted into and fused with PRRSV Nsp2 gene in the PRRSV infectious clone plasmid FL-12 to generate FL12-GFP plasmid. The recombinant PRRSV-GFP was generated through transfecting PRRSV mRNA in BHK-2 cells. Like its parental virus, the recombinant PRRSV-GFP maintains its infectivity to Marc-145 cells and porcine alveolar macrophages (PAMs. This study provides essential conditions for further investigation on PRRSV.

  6. GETDB: 113388 [GETDB

    Lifescience Database Archive (English)

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    Lifescience Database Archive (English)

    Full Text Available NP3591 NP line. Received from the National Institute of Genetics. - - 1 - - 0 - cns uniform epi uni epi, hg ...onic Expression cns Larval GFP uniform epi Larval X-gal uni epi, hg Adult GFP ant

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    Full Text Available 1381 1 Request - leg disc? stripes in abdomenal epi, sg ch organ, PNS, internal ...c Expression leg disc? stripes in abdomenal epi, Larval GFP sg Larval X-gal ch organ, PNS, Adult GFP interna

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    Lifescience Database Archive (English)

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    Lifescience Database Archive (English)

    Full Text Available equest - mixed? one in posterior midgut. other in epidermal stripes. muscle. sh. ...r midgut. other in epidermal stripes. Larval GFP muscle. Larval X-gal sh. Not in disc. Adult GFP - Lethality

  13. Experiment list: SRX092301 [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available escription=This data represents a control being compared to experiments using ant...ibody eGFP-JunD || control=Control_eGFP-JunD || control description=This data represents a control being compare

  14. Experiment list: SRX092300 [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  15. Experiment list: SRX092306 [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available tion=This data represents a control being compared to experiments using antibody ...eGFP-FOS || control=Control_eGFP-FOS || control description=This data represents a control being compared to

  16. GETDB: 112760 [GETDB

    Lifescience Database Archive (English)

    Full Text Available table 1741 1 Request - epi, oenocyte, muscle subset pns tr, epi wing veins - - -...rval GFP pns Larval X-gal tr, epi Adult GFP wing veins Lethality - Also known as - Original Comments - Disc

  17. Yeast Interacting Proteins Database: YDL089W, YML008C [Yeast Interacting Proteins Database

    Lifescience Database Archive (English)

    Full Text Available rDNA repeat stability; null mutant causes increase in unequal sister-chromatid exchange; GFP-fusion protein...peat stability; null mutant causes increase in unequal sister-chromatid exchange; GFP-fusion protein localiz

  18. Gclust Server: 35602 [Gclust Server