Sample records for protoplasts summary progress

  1. Progress in plant protoplast research.

    PubMed

    Eeckhaut, Tom; Lakshmanan, Prabhu Shankar; Deryckere, Dieter; Van Bockstaele, Erik; Van Huylenbroeck, Johan

    2013-12-01

    In this review we focus on recent progress in protoplast regeneration, symmetric and asymmetric hybridization and novel technology developments. Regeneration of new species and improved culture techniques opened new horizons for practical breeding in a number of crops. The importance of protoplast sources and embedding systems is discussed. The study of reactive oxygen species effects and DNA (de)condensation, along with thorough phytohormone monitoring, are in our opinion the most promising research topics in the further strive for rationalization of protoplast regeneration. Following, fusion and fragmentation progress is summarized. Genomic, transcriptomic and proteomic studies have led to better insights in fundamental processes such as cell wall formation, cell development and chromosome rearrangements in fusion products, whether or not obtained after irradiation. Advanced molecular screening methods of both genome and cytoplasmome facilitate efficient screening of both symmetric and asymmetric fusion products. We expect that emerging technologies as GISH, high resolution melting and next generation sequencing will pay major contributions to our insights of genome creation and stabilization, mainly after asymmetric hybridization. Finally, we demonstrate agricultural valorization of somatic hybridization through enumerating recent introgression of diverse traits in a number of commercial crops.

  2. Polyamine levels as related to growth, differentiation and senescence in protoplast-derived cultures of Vigna aconitifolia and Avena sativa

    NASA Technical Reports Server (NTRS)

    Kaur Sawhney, R.; Shekhawat, N. S.; Galston, A. W.

    1985-01-01

    We have previously reported that aseptically cultured mesophyll protoplasts of Vigna divide rapidly and regenerate into complete plants, while mesophyll protoplasts of Avena divide only sporadically and senesce rapidly after isolation. We measured polyamine titers in such cultures of Vigna and Avena, to study possible correlations between polyamines and cellular behavior. We also deliberately altered polyamine titer by the use of selective inhibitors of polyamine biosynthesis, noting the effects on internal polyamine titer, cell division activity and regenerative events. In Vigna cultures, levels of free and bound putrescine and spermidine increased dramatically as cell division and differentiation progressed. The increase in bound polyamines was largest in embryoid-forming callus tissue while free polyamine titer was highest in root-forming callus. In Avena cultures, the levels of total polyamines decreased as the protoplast senesced. The presence of the inhibitors alpha-difluoromethyl-arginine (specific inhibitor of arginine decarboxylase), alpha-difluoromethylornithine (specific inhibitor of ornithine decarboxylase) and dicyclohexylamine (inhibitor of spermidine synthase) reduced cell division and organogenesis in Vigna cultures. Addition of low concentration of polyamines to such cultures containing inhibitors or removal of inhibitors from the culture medium restored the progress of growth and differentiation with concomitant increase in polyamine levels.

  3. A Lactuca universal hybridizer, and its use in creation of fertile interspecific somatic hybrids.

    PubMed

    Chupeau, M C; Maisonneuve, B; Bellec, Y; Chupeau, Y

    1994-10-28

    A Lactuca sativa cv. Ardente line heterozygous for a gene encoding resistance to kanamycin, a positive and dominant trait, was crossed with cv. Girelle, which is heterozygous for a recessive albinism marker. The resulting seeds yielded 25% albino seedlings, of which 50% were also resistant to kanamycin. Such plantlets (KR, a) grown in vitro were used for preparation of universal hybridizer protoplasts, since green buds that can develop on kanamycin containing-medium should result from fusion with any wild-type protoplast. To test the practicability of this selection scheme, we fused L. sativa KR, a protoplasts with protoplasts derived from various wild Lactuca as well as various other related species. Protoplast-derived cell colonies were selected for resistance to kanamycin at the regeneration stage. Green buds were regenerated after fusion with protoplasts of L. tatarica and of L. perennis. So far, 9 interspecific hybrid plants have been characterized morphologically. In addition, random amplified polymorphic DNA (RAPD) analysis with selected primers confirmed that these plants are indeed interspecific hybrids. Some plants are female-fertile and production of backcross progenies with L. sativa is in progress. Since many desirable traits such as resistances to viruses, bacteria and fungi (Bremia lactucae) have been characterized in wild Lactuca species, the use of somatic hybridization in breeding programmes now appears a practical possibility.

  4. [Restriction of virus infection by plants: Annual report, 1986

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bruening, G.

    1986-12-05

    This research concerns the strong resistance, or even immunity, against a specific virus that is exhibited by one or a few lines of a plant species, in contrast to the general susceptibility of most lines of that species. The contrast between the reactions to virus inoculation of different lines of one species implies that a single gene or a very few genes may mediate the resistance or immunity. The prospects for isolating, studying and transferring such a gene should be good for a system with these characteristics. Seedlings of a line Arlington of the cowpea (Vigna unguiculata) fail to supportmore » the replication of cowpea mosaic virus strain SB (CPMV-SB). Genetic crosses of Arlington cowpea to the systemic host Blackeye 5 cowpea show that the immunity is inherited as a simple dominant gene. In contrast to the seedlings, the protoplasts of the Arlington cowpea support CPMV-SB replication, but only to a very low level compared to protoplasts of Blackeye 5 cowpeas. From evidence reported earlier we concluded that Arlington cowpea protoplasts restrict the production of CPMV-SB proteins. We postulated, and obtained evidence for, a proteinase inhibitor that is specific for a CPMV-SB proteinase. This proteinase inhibitor is our prime candidate for the mediator of the resistance of Arlington protoplasts to CPMV-SB. Progress to date is described.« less

  5. (Restriction of virus infection by plants: Annual report, 1986)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bruening, G.

    1986-12-05

    This research concerns the strong resistance, or even immunity, against a specific virus that is exhibited by one or a few lines of a plant species, in contrast to the general susceptibility of most lines of that species. The contrast between the reactions to virus inoculation of different lines of one species implies that a single gene or a very few genes may mediate the resistance or immunity. The prospects for isolating, studying and transferring such a gene should be good for a system with these characteristics. Seedlings of a line Arlington of the cowpea (Vigna unguiculata) fail to supportmore » the replication of cowpea mosaic virus strain SB (CPMV-SB). Genetic crosses of Arlington cowpea to the systemic host Blackeye 5 cowpea show that the immunity is inherited as a simple dominant gene. In contrast to the seedlings, the protoplasts of the Arlington cowpea support CPMV-SB replication, but only to a very low level compared to protoplasts of Blackeye 5 cowpeas. From evidence reported earlier we concluded that Arlington cowpea protoplasts restrict the production of CPMV-SB proteins. We postulated, and obtained evidence for, a proteinase inhibitor that is specific for a CPMV-SB proteinase. This proteinase inhibitor is our prime candidate for the mediator of the resistance of Arlington protoplasts to CPMV-SB. Progress to date is described.« less

  6. Improvement of industrially important microbial strains by genome shuffling: Current status and future prospects.

    PubMed

    Magocha, Tinashe Archbold; Zabed, H; Yang, Miaomiao; Yun, Junhua; Zhang, Huanhuan; Qi, Xianghui

    2018-06-01

    The growing demand for biotechnological products against limited metabolic capacity of industrially used microorganisms has led to an increased interest on strain-improvement over the last several decades, which aimed to enhance metabolite yield, substrate uptake and tolerance of the strains. Among a few techniques of strain-improvement, genome shuffling is the most recent and promising approach used for rapid strain-improvement that can yield a new strain by combining whole genomes of multi-parental microorganisms using the principles of protoplast fusion. Genome shuffling has brought a major breakthrough in the strain-improvement concept as it is found to be effective and reliable for expressing complex phenotypes. This review will discuss the technical aspects and applications of genome shuffling for various industrial strains to present its current status and recent progress. In the concluding remarks, a summary will be presented focusing on the major challenges and future outlooks of this technology. Copyright © 2018 Elsevier Ltd. All rights reserved.

  7. Genetic transformation of the white-rot fungus Dichomitus squalens using a new commercial protoplasting cocktail.

    PubMed

    Daly, Paul; Slaghek, Gillian G; Casado López, Sara; Wiebenga, Ad; Hilden, Kristiina S; de Vries, Ronald P; Mäkelä, Miia R

    2017-12-01

    D. squalens, a white-rot fungus that efficiently degrades lignocellulose in nature, can be used in various biotechnological applications and has several strains with sequenced and annotated genomes. Here we present a method for the transformation of this basidiomycete fungus, using a recently introduced commercial ascomycete protoplasting enzyme cocktail, Protoplast F. In protoplasting of D. squalens mycelia, Protoplast F outperformed two other cocktails while releasing similar amounts of protoplasts to a third cocktail. The protoplasts released using Protoplast F had a regeneration rate of 12.5% (±6 SE). Using Protoplast F, the D. squalens monokaryon CBS464.89 was conferred with resistance to the antibiotics hygromycin and G418 via polyethylene glycol mediated protoplast transformation with resistance cassettes expressing the hygromycin phosphotransferase (hph) and neomycin phosphotransferase (nptII) genes, respectively. The hph gene was expressed in D. squalens using heterologous promoters from genes encoding β-tubulin or glyceraldehyde 3-phosphate dehydrogenase. A Southern blot confirmed integration of a resistance cassette into the D. squalens genome. An average of six transformants (±2 SE) were obtained when at least several million protoplasts were used (a transformation efficiency of 0.8 (±0.3 SE) transformants per μg DNA). Transformation of D. squalens demonstrates the suitability of the Protoplast F cocktail for basidiomycete transformation and furthermore can facilitate understanding of basidiomycete gene function and development of improved strains for biotechnological applications. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Protoplast isolation and genetically true-to-type plant regeneration from leaf- and callus-derived protoplasts of Albizia julibrissin

    Treesearch

    Mohammad-Shafie Rahmani; Paula M. Pijut; Naghi Shabanian

    2016-01-01

    Protoplast isolation and subsequent plant regeneration of Albizia julibrissin was achieved from leaf and callus explants. Leaf tissue from 4 to 5-week-old in vitro seedlings was the best source for high-yield protoplast isolation. This approach produced 7.77 × 105 protoplasts (Pp) per gram fresh weight with 94 % viability;...

  9. Functional Sieve Element Protoplasts1[OA

    PubMed Central

    Hafke, Jens B.; Furch, Alexandra C.U.; Reitz, Marco U.; van Bel, Aart J.E.

    2007-01-01

    Sieve element (SE) protoplasts were liberated by exposing excised phloem strands of Vicia faba to cell wall-degrading enzyme mixtures. Two types of SE protoplasts were found: simple protoplasts with forisome inclusions and composite twin protoplasts—two protoplasts intermitted by a sieve plate—of which one protoplast often includes a forisome. Forisomes are giant protein inclusions of SEs in Fabaceae. Membrane integrity of SE protoplasts was tested by application of CFDA, which was sequestered in the form of carboxyfluorescein. Further evidence for membrane intactness was provided by swelling of SE protoplasts and forisome dispersion in reaction to abrupt lowering of medium osmolarity. The absence of cell wall remnants as demonstrated by negative Calcofluor White staining allowed patch-clamp studies. At negative membrane voltages, the current-voltage relations of the SE protoplasts were dominated by a weak inward-rectifying potassium channel that was active at physiological membrane voltages of the SE plasma membrane. This channel had electrical properties that are reminiscent of those of the AKT2/3 channel family, localized in phloem cells of Arabidopsis (Arabidopsis thaliana). All in all, SE protoplasts promise to be a powerful tool in studying the membrane biology of SEs with inherent implications for the understanding of long-distance transport and signaling. PMID:17885083

  10. [Optimized condition for protoplast isolation from maize, wheat and rice leaves].

    PubMed

    Sun, He; Lang, Zhihong; Zhu, Li; Huang, Dafang

    2013-02-01

    Maize (Zea mays L.), wheat (Triticum aestivum L.) and rice (Oryza sativa L.) are three staple crops and accordingly it is very meaningful to optimize the condition of their protoplasts isolation. The concentration of the enzyme, the time of isolation and centrifugal force in protoplast isolation were investigated to find their effects on protoplast yield and viability using leaves of maize (Zong 3), wheat (Chinese Spring) and rice (Nipponbare). The results show that the concentration of the enzyme and the time of isolation affected the protoplast yield significantly. Although the yield of protoplast was increased with high concentration of enzyme and long incubated time, it led to too much cells breakdown. The orthogonal experimental design results show that the best condition of maize protoplast isolation was Cellulase R-10 1.5%, Macerozyme R-10 0.5%, 50 r/min 7 h, 100 x g 2 min and the protoplasts yield was 7x106 cells/g fresh weight (FW); the best condition of wheat protoplast isolation was Cellulase R-10 1.5%, Macerozyme R-10 0.5%, 50 r/min 5 h, 100 x g 2 min and the protoplasts yield was 6 x 10(6) cells/g FW; the best condition of rice protoplast isolation was Cellulase R-10 2.0%, Macerozyme R-10 0.7%, 50 r/min 7 h, 1 000 x g 2 min and the protoplasts yield was 6x10(6) cells/g FW. The vitalities were more than 90% using fluorescein diacetate staining method. 50%-80% transformation efficiency was obtained when protoplasts were transformed by green fluorescent protein using PEG-Ca2+ method.

  11. Rapid release of protoplasts from Eremothecium ashbyii in comparison with Trichoderma reesei and Penicillium chrysogenum using novozyme and funcelase.

    PubMed

    Lakshmi, B R; Chandra, T S

    1993-08-01

    Protoplast release in Eremothecium ashbyii, Trichoderma reesei, and Penicillium chrysogenum was achieved using commercially available enzymes, Novozyme 234 and Funcelase. A rapid release of protoplasts was observed in E. ashbyii, yielding nearly 4.0 x 10(7) protoplasts ml-1 in 10-35 min. The regeneration frequency of protoplasts from T. reesei, P. chrysogenum, and E. ashbyii using Funcelase was 51.77, 28.32, and 7.64%, respectively, and was higher in comparison with Novozyme-derived protoplasts.

  12. [Preparation and vitality detection of protoplast in Salvia miltiorrhiza Bunge].

    PubMed

    Zhu, Nan; Liu, Jun; Zhang, Xinyu; Dong, Juan'e

    2014-10-01

    We prepared protoplasts from Salvia miltiorrhiza Bunge suspension culture cells. Then, the protoplasts' vitality and functions were tested by fluorescein diacetate staining method and Fluo-3/AM flourescent probe. The optimal condition of protoplast isolation was Cellulase R-10 1.5%, Pectinase Y-23 0.3%, Macerozyme R-10 0.5%, 40 r/min 12 h, 600 r/min 5 min, and the protoplasts yield was 1.1x10(6) cells/g FW, the vitality was more than 95% by using fluorescein diacetate staining method. It has been confirmed that calcium fluorescent probe Fluo-3/AM can be successfully loaded into protoplasts.

  13. The retraction of the protoplast during PCD is an active, and interruptible, calcium-flux driven process.

    PubMed

    Kacprzyk, Joanna; Brogan, Niall P; Daly, Cara T; Doyle, Siamsa M; Diamond, Mark; Molony, Elizabeth M; McCabe, Paul F

    2017-07-01

    The protoplast retracts during apoptosis-like programmed cell death (AL-PCD) and, if this retraction is an active component of AL-PCD, it should be used as a defining feature for this type of programmed cell death. We used an array of pharmacological and genetic tools to test if the rates of protoplast retraction in cells undergoing AL-PCD can be modulated. Disturbing calcium flux signalling, ATP synthesis and mitochondrial permeability transition all inhibited protoplast retraction and often also the execution of the death programme. Protoplast retraction can precede loss of plasma membrane integrity and cell death can be interrupted after the protoplast retraction had already occurred. Blocking calcium influx inhibited the protoplast retraction, reduced DNA fragmentation and delayed death induced by AL-PCD associated stresses. At higher levels of stress, where cell death occurs without protoplast retraction, blocking calcium flux had no effect on the death process. The results therefore strongly suggest that retraction of the protoplast is an active biological process dependent on an early Ca 2+ -mediated trigger rather than cellular disintegration due to plasma membrane damage. Therefore this morphologically distinct cell type is a quantifiable feature, and consequently, reporter of AL-PCD. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Transformation of Clostridium acetobutylicum Protoplasts with Bacteriophage DNA

    PubMed Central

    Reid, Sharon J.; Allcock, Errol R.; Jones, David T.; Woods, David R.

    1983-01-01

    Techniques for the transformation of Clostridium acetobutylicum protoplasts with bacteriophage DNA are described. Transformation required regeneration of protoplasts and a 2-h eclipse period. PMID:16346174

  15. Dendrobium protoplast co-culture promotes phytochemical assemblage in vitro.

    PubMed

    Thomas, Abitha; Pujari, Ipsita; Shetty, Vasudeep; Joshi, Manjunath B; Rai, Padmalatha S; Satyamoorthy, Kapaettu; Babu, Vidhu Sankar

    2017-07-01

    The present study is intended to analyze the occurrence of potent, low produce, naturally occurring stilbenes in protoplasts of wild species and hybrids of Dendrobium. The wild species selected for the study was Dendrobium ovatum, endemic to Western Ghats of India. Protoplasts were isolated from leaves and tepal tissues of all the species and were cultured purely to generate homofusants and cross-cultured to raise heterofusants. Phytochemical composition of protoplast culture with atypical and pure microcolonies was performed using mass spectrometry. Enzyme cocktail of 4% pectinase together with 2% cellulase displayed the highest competence for protoplast isolations. Maximum protoplast density of 30.11 × 10 4 /ml was obtained from D. ovatum leaves in 2 h. Subcellular features such as the presence of partially formed cell wall, the position of the nucleus, chloroplast density, colony existence, and integrity of the plasma membrane were analyzed. Among the pure and cross-cultured protoplasts, the number of heterofusants and homofusants formed were enumerated. The spectral feature extraction of the mass spectrometry indicated the presence of five phenolic marker compounds, viz., tristin, confusarin, gigantol, moscatilin, and resveratrol, some of them in pure and others in assorted protoplast cultures raised from Dendrobium leaves and tepals. The study demonstrated that protoplast fusion technique enabled phytochemical assemblage in vitro as stilbenes tend to get restricted either in a tissue or species specific manner. This is the first report showing the presence of resveratrol, moscatilin, tristin, gigantol, and confusarin in wild and hybrid species from cultured Dendrobium protoplasts in vitro.

  16. Efficient production of Aschersonia placenta protoplasts for transformation using optimization algorithms.

    PubMed

    Wei, Xiuyan; Song, Xinyue; Dong, Dong; Keyhani, Nemat O; Yao, Lindan; Zang, Xiangyun; Dong, Lili; Gu, Zijian; Fu, Delai; Liu, Xingzhong; Qiu, Junzhi; Guan, Xiong

    2016-07-01

    The insect pathogenic fungus Aschersonia placenta is a highly effective pathogen of whiteflies and scale insects. However, few genetic tools are currently available for studying this organism. Here we report on the conditions for the production of transformable A. placenta protoplasts using an optimized protocol based on the response surface method (RSM). Critical parameters for protoplast production were modelled by using a Box-Behnken design (BBD) involving 3 levels of 3 variables that was subsequently tested to verify its ability to predict protoplast production (R(2) = 0.9465). The optimized conditions resulted in the highest yield of protoplasts ((4.41 ± 0.02) × 10(7) cells/mL of culture, mean ± SE) when fungal cells were treated with 26.1 mg/mL of lywallzyme for 4 h of digestion, and subsequently allowed to recover for 64.6 h in 0.7 mol/L NaCl-Tris buffer. The latter was used as an osmotic stabilizer. The yield of protoplasts was approximately 10-fold higher than that of the nonoptimized conditions. Generated protoplasts were transformed with vector PbarGPE containing the bar gene as the selection marker. Transformation efficiency was 300 colonies/(μg DNA·10(7) protoplasts), and integration of the vector DNA was confirmed by PCR. The results show that rational design strategies (RSM and BBD methods) are useful to increase the production of fungal protoplasts for a variety of downstream applications.

  17. Isoelectric Focusing of Cassava Protoplasts

    PubMed Central

    Santana, María Angélica; Villegas, Leopoldo

    1991-01-01

    Cassava (Manihot esculenta Crantz) protoplast was analyzed by using isoelectric focusing techniques. Two populations, representing 68 and 32% of the total sample, with mean isoelectric points of 4.48 and 4.60, were obtained using mesophyll protoplasts. The use of this technique allows demonstration of a discontinuous distribution of protoplast isoelectric point from one species according to their surface potential. Images Figure 1 PMID:16667975

  18. Gravity and light control of the developmental polarity of regenerating protoplasts isolated from prothallial cells of the fern Ceratopteris richardii

    NASA Technical Reports Server (NTRS)

    Edwards, E. S.; Roux, S. J.

    1998-01-01

    A procedure has been developed for isolating protoplasts from prothalli of Ceratopteris richardii which can be cultured and are capable of regeneration. Protoplasts were isolated from 2-week-old gametophytes in a medium containing wall-digesting enzymes in 0.5 M sucrose, followed by purification of the released protoplasts by floating them up into a 0.5 M sorbitol layer. Regeneration occurred over a period of 10-24 days, and, under optimal osmotic conditions, followed the developmental pattern seen during spore germination, in that the first division gave rise to a primary rhizoid. Thus, prothallial protoplasts are comparable to germinating spores as suitable models for studies of developmental polarity in single cells. As in germinating spores, the polarity of development in regenerating protoplasts is influenced by the vectors of gravity and unilateral light. However, the relative influence of light in fixing this polarity is greater in regenerating protoplasts, while in germinating spores, the influence of gravity is greater.

  19. Polyamine metabolism and osmotic stress. I. Relation to protoplast viability

    NASA Technical Reports Server (NTRS)

    Tiburcio, A. F.; Masdeu, M. A.; Dumortier, F. M.; Galston, A. W.

    1986-01-01

    Cereal leaves subjected to the osmotica routinely used for protoplast isolation show a rapid increase in arginine decarboxylase activity, a massive accumulation of putrescine, and slow conversion of putrescine to the higher polyamines, spermidine and spermine (HE Flores, AW Galston 1984 Plant Physiol 75: 102). Mesophyll protoplasts from these leaves, which have a high putrescine:polyamine ratio, do not undergo sustained division. By contrast, in Nicotiana, Capsicum, Datura, Trigonella, and Vigna, dicot genera that readily regenerate plants from mesophyll protoplasts, the response of leaves to osmotic stress is opposite to that in cereals. Putrescine titer as well as arginine and ornithine decarboxylase activities decline in these osmotically stressed dicot leaves, while spermidine and spermine titers increase. Thus, the putrescine:polyamine ratio in Vigna protoplasts, which divide readily, is 4-fold lower than in oat protoplasts, which divide poorly. We suggest that this differing response of polyamine metabolism to osmotic stress may account in part for the failure of cereal mesophyll protoplasts to develop readily in vitro.

  20. [Isolation and regeneration of the protoplasts of the streptomycete producers of actinomycins C and X].

    PubMed

    Orlova, T I; Masha, G G; Kliueva, N A

    1986-09-01

    Protoplasts of S. michiganensis, S. chrysomallus and Streptomyces sp. 26-115, organisms producing actinomycins C and X form in hypertonic salt solution under the action of 3-4,5 mg/ml of lysozyme on the mycelium suspension. For protoplasting, the streptomycetes were grown on the soybean medium in the presence of 0.2-0.8 per cent of glycine. The mycelium of the streptomycete exponential growth phase was more favourable for protoplast formation. Protoplast regeneration was studied on the medium described by Okanishi et al. The quantitative composition of this medium was not optimal for regeneration of protoplasts of the above streptomycetes. The level of their regeneration depended to various extents on concentration of phosphate, magnesium and calcium ions and sucrose in the regeneration medium.

  1. Microcalli Induction in Protoplasts Isolated from Embryogenic Callus of Date Palm.

    PubMed

    Titouh, Khayreddine; Boufis, Nazim; Khelifi, Lakhdar

    2017-01-01

    Date palm (Phoenix dactylifera L.) production is severely hampered due to several pests and diseases. Biotechnological tools such as protoplast fusion appear as an alternative to ensure rapid genetic improvement and multiplication of this species. However, establishment of an effective system of plant regeneration from protoplasts culture is a prerequisite for date palm somatic hybridization. In this chapter, we describe an effective protocol to induce microcalli in protoplasts isolated from nodular callus of important Algerian date palm cultivars. In this protocol, the main factors influencing the isolation (i.e., enzymatic solution, mannitol concentration, duration, and mode of maceration) of protoplasts from the calli of Algerian date palm cultivars were optimized. Purified protoplasts were cultured on a semisolid medium supplemented with a hormonal balance of auxin and cytokinin to obtain microcalli formation.

  2. Relationship between Respiration and Photosynthesis in Guard Cell and Mesophyll Cell Protoplasts of Commelina communis L

    PubMed Central

    Gautier, Hélène; Vavasseur, Alain; Gans, Pierre; Lascève, Gérard

    1991-01-01

    A mass spectrometric method combining 16O/18O and 12C/13C isotopes was used to quantify the unidirectional fluxes of O2 and CO2 during a dark to light transition for guard cell protoplasts and mesophyll cell protoplasts of Commelina communis L. In darkness, O2 uptake and CO2 evolution were similar on a protein basis. Under light, guard cell protoplasts evolved O2 (61 micromoles of O2 per milligram of chlorophyll per hour) almost at the same rate as mesophyll cell protoplasts (73 micromoles of O2 per milligram of chlorophyll per hour). However, carbon assimilation was totally different. In contrast with mesophyll cell protoplasts, guard cell protoplasts were able to fix CO2 in darkness at a rate of 27 micromoles of CO2 per milligram of chlorophyll per hour, which was increased by 50% in light. At the onset of light, a delay observed for guard cell protoplasts between O2 evolution and CO2 fixation and a time lag before the rate of saturation suggested a carbon metabolism based on phosphoenolpyruvate carboxylase activity. Under light, CO2 evolution by guard cell protoplasts was sharply decreased (37%), while O2 uptake was slowly inhibited (14%). A control of mitochondrial activity by guard cell chloroplasts under light via redox equivalents and ATP transfer in the cytosol is discussed. From this study on protoplasts, we conclude that the energy produced at the chloroplast level under light is not totally used for CO2 assimilation and may be dissipated for other purposes such as ion uptake. PMID:16668030

  3. A lower content of de-methylesterified homogalacturonan improves enzymatic cell separation and isolation of mesophyll protoplasts in Arabidopsis.

    PubMed

    Lionetti, Vincenzo; Cervone, Felice; De Lorenzo, Giulia

    2015-04-01

    Cell adhesion occurs primarily at the level of middle lamella which is mainly composed by pectin polysaccharides. These can be degraded by cell wall degrading enzymes (CWDEs) during developmental processes to allow a controlled separation of plant cells. Extensive cell wall degradation by CWDEs with consequent cell separation is performed when protoplasts are isolated from plant tissues by using mixtures of CWDEs. We have evaluated whether modification of pectin affects cell separation and protoplast isolation. Arabidopsis plants overexpressing the pectin methylesterase inhibitors AtPMEI-1 or AtPMEI-2, and Arabidopsis pme3 plants, mutated in the gene encoding pectin methylesterase 3, showed an increased efficiency of isolation of viable mesophyll protoplasts as compared with Wild Type Columbia-0 plants. The release of protoplasts was correlated with the reduced level of long stretches of de-methylesterified homogalacturonan (HGA) present in these plants. Response to elicitation, cell wall regeneration and efficiency of transfection in protoplasts from transgenic plants was comparable to those of wild type protoplasts. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Isolation and regeneration protoplast of an oil palm pathogen, Ganoderma boninense

    NASA Astrophysics Data System (ADS)

    Irene, Liza Isaac; Bakar, Farah Diba Abu; Idris, Abu Seman; Murad, Abdul Munir Abdul

    2015-09-01

    Ganoderma boninense is a known cause for basal stem rot (BSR) in oil palm. Thus, to curb the infection towards oil palm, the establishment of protoplast isolation and regeneration protocol is crucial to be studied. This will provide information on the functional genes especially those which leads towards infection and pathogenicity. In this study, a method was outlined to isolated protoplast in G. boninense by manipulating parameters such as mycelium age, concentration of lysing enzyme, and duration of mycelia incubation in lytic solution. The results shows that from 0.1 g of wet weight mycelia, the highest protoplast yield obtained was 5.5 × 108 protoplast/ml using 5th day old culture in a lytic mixture containing 2.0 % of lysing enzyme incubated for 4 hours at 30 °C with agitation of 80-100 rpm. The highest percentage of protoplast regeneration obtained from this study was 0.2 % using CYM medium supplemented with 0.6 M sorbitol. To date, this is the first report of protoplast isolation and regeneration for this phytopathogen.

  5. Myo-Inositol trisphosphate mobilizes calcium from fusogenic carrot (Daucus carota L. ) protoplasts

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rincon, M.; Boss, W.F.

    1987-02-01

    To determine whether or not inositol trisphosphate (IP/sub 3/) mobilizes calcium in higher plant cells; they investigated the effect of IP/sub 3/ on Ca/sup 2 +/ fluxes in fusogenic carrot (Daucus carota L.) protoplasts. The protoplasts were incubated in /sup 45/Ca/sup 2 +/-containing medium and the /sup 45/Ca/sup 2 +/ associated with the protoplasts was monitored with time. Addition of IP/sub 3/ (20 micromolar) caused a 17% net loss of the accumulated /sup 45/Ca/sup 2 +/ within 4 minutes. There was a reuptake of /sup 45/Ca/sup 2 +/ and the protoplasts recovered to their initial value by 10 minutes. Phyticmore » acid (IP/sub 6/), also stimulated /sup 45/Ca/sup 2 +/ efflux from the protoplasts. Both the IP/sub 3/- and the IP/sub 6/-induced /sup 45/Ca/sup 2 +/ efflux were inhibited by the calmodulin antagonist, trifluoperazine.« less

  6. Plant regeneration from protoplasts of embryogenic cell suspensions of Coffea arabica L. cv. caturra.

    PubMed

    Acuna, J R; de Pena, M

    1991-09-01

    Coffee plants were regenerated from protoplasts isolated from embryogenic cell suspension cultures derived from somatic embryos of Coffea arabica L. cv. caturra. Yields of viable protoplasts ranged from 1×10(5) to 6×10(5) protoplast/g fresh weight. Protoplast preparations usually contained no contaminating cells, and when present, the number of cells never exceeded 0.1% of the total. Plating efficiencies of protoplast ranged from 1 to 10%. Embryogenic protocolonies obtained after several subcultures in a medium supplemented with 0.5 mg/l each of benzylaminopurine, 2,4-dichlorophenoxyacetic acid and naphtaleneacetic acid, were transferred to a medium lacking plant growth regulators. Well differentiated embryos were formed in selected protocolonies that contained many embryos-like structures. Approximately 70% of the somatic embryos developed into green rooted plantlets which were succesfully transferred to vessels containing sterilized scoria. Plants grown for two months in scoria were finally transferred to greenhouse.

  7. Polypeptide synthesis induced in Nicotiana clevelandii protoplasts by infection with raspberry ringspot nepovirus.

    PubMed

    Acosta, O; Mayo, M A

    1993-01-01

    Infection of Nicotiana clevelandii protoplasts by raspberry ringspot nepovirus resulted in the accumulation of about 24 polypeptides that differed in M(r) and pI from polypeptides accumulating in mock-inoculated protoplasts. Similar polypeptides accumulated in protoplasts infected with the S and E strains of RRV but different infection-specific polypeptides were detected in protoplasts infected with tobacco ringspot nepovirus. The M(r) of RRV-specific polypeptides ranged from 210,000 to 18,000 and most are presumed to be derived from others by proteolytic cleavage. No evidence was found for marked changes in polypeptide abundance with time after inoculation or for any virus-specific polypeptide becoming disproportionately abundant in the medium during culture.

  8. Efficient transformation of oil palm protoplasts by PEG-mediated transfection and DNA microinjection.

    PubMed

    Masani, Mat Yunus Abdul; Noll, Gundula A; Parveez, Ghulam Kadir Ahmad; Sambanthamurthi, Ravigadevi; Prüfer, Dirk

    2014-01-01

    Genetic engineering remains a major challenge in oil palm (Elaeis guineensis) because particle bombardment and Agrobacterium-mediated transformation are laborious and/or inefficient in this species, often producing chimeric plants and escapes. Protoplasts are beneficial as a starting material for genetic engineering because they are totipotent, and chimeras are avoided by regenerating transgenic plants from single cells. Novel approaches for the transformation of oil palm protoplasts could therefore offer a new and efficient strategy for the development of transgenic oil palm plants. We recently achieved the regeneration of healthy and fertile oil palms from protoplasts. Therefore, we focused on the development of a reliable PEG-mediated transformation protocol for oil palm protoplasts by establishing and validating optimal heat shock conditions, concentrations of DNA, PEG and magnesium chloride, and the transfection procedure. We also investigated the transformation of oil palm protoplasts by DNA microinjection and successfully regenerated transgenic microcalli expressing green fluorescent protein as a visible marker to determine the efficiency of transformation. We have established the first successful protocols for the transformation of oil palm protoplasts by PEG-mediated transfection and DNA microinjection. These novel protocols allow the rapid and efficient generation of non-chimeric transgenic callus and represent a significant milestone in the use of protoplasts as a starting material for the development of genetically-engineered oil palm plants.

  9. Efficient Transformation of Oil Palm Protoplasts by PEG-Mediated Transfection and DNA Microinjection

    PubMed Central

    Masani, Mat Yunus Abdul; Noll, Gundula A.; Parveez, Ghulam Kadir Ahmad; Sambanthamurthi, Ravigadevi; Prüfer, Dirk

    2014-01-01

    Background Genetic engineering remains a major challenge in oil palm (Elaeis guineensis) because particle bombardment and Agrobacterium-mediated transformation are laborious and/or inefficient in this species, often producing chimeric plants and escapes. Protoplasts are beneficial as a starting material for genetic engineering because they are totipotent, and chimeras are avoided by regenerating transgenic plants from single cells. Novel approaches for the transformation of oil palm protoplasts could therefore offer a new and efficient strategy for the development of transgenic oil palm plants. Methodology/Principal Findings We recently achieved the regeneration of healthy and fertile oil palms from protoplasts. Therefore, we focused on the development of a reliable PEG-mediated transformation protocol for oil palm protoplasts by establishing and validating optimal heat shock conditions, concentrations of DNA, PEG and magnesium chloride, and the transfection procedure. We also investigated the transformation of oil palm protoplasts by DNA microinjection and successfully regenerated transgenic microcalli expressing green fluorescent protein as a visible marker to determine the efficiency of transformation. Conclusions/Significance We have established the first successful protocols for the transformation of oil palm protoplasts by PEG-mediated transfection and DNA microinjection. These novel protocols allow the rapid and efficient generation of non-chimeric transgenic callus and represent a significant milestone in the use of protoplasts as a starting material for the development of genetically-engineered oil palm plants. PMID:24821306

  10. Optimization of Production Conditions for Protoplasts and Polyethylene Glycol-Mediated Transformation of Gaeumannomyces tritici.

    PubMed

    Wang, Mei; Zhang, Jie; Wang, Lanying; Han, Lirong; Zhang, Xing; Feng, Juntao

    2018-05-24

    Take-all, caused by Gaeumannomyces tritici , is one of the most important wheat root diseases worldwide, as it results in serious yield losses. In this study, G. tritici was transformed to express the hygromycin B phosphotransferase using a combined protoplast and polyethylene glycol (PEG)-mediated transformation technique. Based on a series of single-factor experimental results, three major factors-temperature, enzyme lysis time, and concentration of the lysing enzyme-were selected as the independent variables, which were optimized using the response surface methodology. A higher protoplast yield of 9.83 × 10⁷ protoplasts/mL was observed, and the protoplast vitality was also high, reaching 96.27% after optimization. Protoplasts were isolated under the optimal conditions, with the highest transformation frequency (46⁻54 transformants/μg DNA). Polymerase chain reaction and Southern blotting detection indicated that the genes of hygromycin phosphotransferase were successfully inserted into the genome of G. tritici . An optimised PEG-mediated protoplast transformation system for G. tritici was established. The techniques and procedures described will lay the foundation for establishing a good mutation library of G. tritici and could be used to transform other fungi.

  11. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hahne, G.; Hoffmann, F.

    A serious problem in the technology of plant cell culture is that isolated protoplasts from many species are reluctant to divide. We have succeeded in inducing consecutive divisions in a naturally arrested system i.e., protoplasts from a hibiscus cell line, which do not divide under standard conditions and in an artificially arrested system i.e., colchicine-inhibited callus protoplasts of Nicotiana glutinosa, which do readily divide in the absence of colchicine. In both cases, the reinstallation of a net of cortical microtubules, which had been affected either by colchicine or by the protoplast isolation procedure, resulted in continuous divisions of the formerlymore » arrested protoplasts. Several compounds known to support microtubule assembly in vitro were tested for their ability to promote microtubule assembly in vivo. Best results were obtained by addition of dimethyl sulfoxide to the culture medium. Unlimited amounts of callus could be produced with the dimethyl sulfoxide method from protoplasts which never developed a single callus in control experiments. 30 references, 3 figures.« less

  12. A simplified Protocol to Induce Callogenesis in Protoplasts of Date Palm (Phoenix dactylifera L.) Cultivars.

    PubMed

    Titouh, Khayreddine; Khelifi, Lakhdar; Slaoui, Majda; Boufis, Nazim; Morsli, Abdelkader; Hadj Moussa, Khadidja Titouh; Makhzoum, Abdullah

    2015-03-01

    In Algeria, date palm is currently confronted to the Bayoud disease. Biotechnological tools such as protoplastsfusion can appear as an alternative to ensure rapid multiplication and improvement of this species. Callogenesis induction in protoplasts isolated from embryogenic callus of three date palm cultivars. Some factors influencing the isolation and culture of protoplasts segregated from the calli of three date palm ( Phoenix dactylifera L.) cultivars (Deglet Nour, Akerbouch and Degla Beida) were studied. Protoplasts of each cultivar were cultured on a semi-solid medium supplemented with various hormonal balances. Maceration with an enzymatic solution containing 1.5% cellulase and 1% macerozyme R10 in the presence of 0.5 M mannitol for more than 16 h with gentle agitation allows isolation of a great number of viable protoplasts. In addition, purification of protoplasts on a cushion of 21 or 25% sucrose was effective in cell debris removal and maximum recovery. The culture of isolated protoplasts on a semi-solidified Murashige and Skoog medium, with 0.3% agarose, 2 mg. L -1 2,4-D and 0.5 mg.L -1 BAP allowed good viable protoplast maintenance as well as cell wall regeneration. After more than two months of culture, cell divisions were still occurring and microcalli became visible to the naked eye, containing a large number of cells. The developed protocol can be useful for application of somatic hybridization to improve date palm cultivars.

  13. Expanding the Symbiodinium (Dinophyceae, Suessiales) Toolkit Through Protoplast Technology.

    PubMed

    Levin, Rachel A; Suggett, David J; Nitschke, Matthew R; van Oppen, Madeleine J H; Steinberg, Peter D

    2017-09-01

    Dinoflagellates within the genus Symbiodinium are photosymbionts of many tropical reef invertebrates, including corals, making them central to the health of coral reefs. Symbiodinium have therefore gained significant research attention, though studies have been constrained by technical limitations. In particular, the generation of viable cells with their cell walls removed (termed protoplasts) has enabled a wide range of experimental techniques for bacteria, fungi, plants, and algae such as ultrastructure studies, virus infection studies, patch clamping, genetic transformation, and protoplast fusion. However, previous studies have struggled to remove the cell walls from armored dinoflagellates, potentially due to the internal placement of their cell walls. Here, we produce the first Symbiodinium protoplasts from three genetically and physiologically distinct strains via incubation with cellulase and osmotic agents. Digestion of the cell walls was verified by a lack of Calcofluor White fluorescence signal and by cell swelling in hypotonic culture medium. Fused protoplasts were also observed, motivating future investigation into intra- and inter-specific somatic hybridization of Symbiodinium. Following digestion and transfer to regeneration medium, protoplasts remained photosynthetically active, regrew cell walls, regained motility, and entered exponential growth. Generation of Symbiodinium protoplasts opens exciting, new avenues for researching these crucial symbiotic dinoflagellates, including genetic modification. © 2017 The Author(s) Journal of Eukaryotic Microbiology © 2017 International Society of Protistologists.

  14. Inhibition of phenylpropanoid biosynthesis increases cell wall digestibility, protoplast isolation, and facilitates sustained cell division in American elm (Ulmus americana).

    PubMed

    Jones, A Maxwell P; Chattopadhyay, Abhishek; Shukla, Mukund; Zoń, Jerzy; Saxena, Praveen K

    2012-05-30

    Protoplast technologies offer unique opportunities for fundamental research and to develop novel germplasm through somatic hybridization, organelle transfer, protoclonal variation, and direct insertion of DNA. Applying protoplast technologies to develop Dutch elm disease resistant American elms (Ulmus americana L.) was proposed over 30 years ago, but has not been achieved. A primary factor restricting protoplast technology to American elm is the resistance of the cell walls to enzymatic degradation and a long lag phase prior to cell wall re-synthesis and cell division. This study suggests that resistance to enzymatic degradation in American elm was due to water soluble phenylpropanoids. Incubating tobacco (Nicotiana tabacum L.) leaf tissue, an easily digestible species, in aqueous elm extract inhibits cell wall digestion in a dose dependent manner. This can be mimicked by p-coumaric or ferulic acid, phenylpropanoids known to re-enforce cell walls. Culturing American elm tissue in the presence of 2-aminoindane-2-phosphonic acid (AIP; 10-150 μM), an inhibitor of phenylalanine ammonia lyase (PAL), reduced flavonoid content, decreased tissue browning, and increased isolation rates significantly from 11.8% (±3.27) in controls to 65.3% (±4.60). Protoplasts isolated from callus grown in 100 μM AIP developed cell walls by day 2, had a division rate of 28.5% (±3.59) by day 6, and proliferated into callus by day 14. Heterokaryons were successfully produced using electrofusion and fused protoplasts remained viable when embedded in agarose. This study describes a novel approach of modifying phenylpropanoid biosynthesis to facilitate efficient protoplast isolation which has historically been problematic for American elm. This isolation system has facilitated recovery of viable protoplasts capable of rapid cell wall re-synthesis and sustained cell division to form callus. Further, isolated protoplasts survived electrofusion and viable heterokaryons were produced. Together, these results provide the first evidence of sustained cell division, callus regeneration, and potential application of somatic cell fusion in American elm, suggesting that this source of protoplasts may be ideal for genetic manipulation of this species. The technological advance made with American elm in this study has potential implications in other woody species for fundamental and applied research which require availability of viable protoplasts.

  15. Inhibition of phenylpropanoid biosynthesis increases cell wall digestibility, protoplast isolation, and facilitates sustained cell division in American elm (Ulmus americana)

    PubMed Central

    2012-01-01

    Background Protoplast technologies offer unique opportunities for fundamental research and to develop novel germplasm through somatic hybridization, organelle transfer, protoclonal variation, and direct insertion of DNA. Applying protoplast technologies to develop Dutch elm disease resistant American elms (Ulmus americana L.) was proposed over 30 years ago, but has not been achieved. A primary factor restricting protoplast technology to American elm is the resistance of the cell walls to enzymatic degradation and a long lag phase prior to cell wall re-synthesis and cell division. Results This study suggests that resistance to enzymatic degradation in American elm was due to water soluble phenylpropanoids. Incubating tobacco (Nicotiana tabacum L.) leaf tissue, an easily digestible species, in aqueous elm extract inhibits cell wall digestion in a dose dependent manner. This can be mimicked by p-coumaric or ferulic acid, phenylpropanoids known to re-enforce cell walls. Culturing American elm tissue in the presence of 2-aminoindane-2-phosphonic acid (AIP; 10-150 μM), an inhibitor of phenylalanine ammonia lyase (PAL), reduced flavonoid content, decreased tissue browning, and increased isolation rates significantly from 11.8% (±3.27) in controls to 65.3% (±4.60). Protoplasts isolated from callus grown in 100 μM AIP developed cell walls by day 2, had a division rate of 28.5% (±3.59) by day 6, and proliferated into callus by day 14. Heterokaryons were successfully produced using electrofusion and fused protoplasts remained viable when embedded in agarose. Conclusions This study describes a novel approach of modifying phenylpropanoid biosynthesis to facilitate efficient protoplast isolation which has historically been problematic for American elm. This isolation system has facilitated recovery of viable protoplasts capable of rapid cell wall re-synthesis and sustained cell division to form callus. Further, isolated protoplasts survived electrofusion and viable heterokaryons were produced. Together, these results provide the first evidence of sustained cell division, callus regeneration, and potential application of somatic cell fusion in American elm, suggesting that this source of protoplasts may be ideal for genetic manipulation of this species. The technological advance made with American elm in this study has potential implications in other woody species for fundamental and applied research which require availability of viable protoplasts. PMID:22646730

  16. Use of protoplast, cell, and shoot tip culture in an elm germ plasm improvement program

    Treesearch

    R. Daniel Lineberger; M.B. Sticklen; P.M. Pijut; Mark A. Kroggel; C.V.M. Fink; S.C. Domir

    1990-01-01

    An elm germplasm improvement program was established using three distinct approaches: (1) development of protoplast regeneration protocols with the goal of attempting somatic hybridization between Ulmus americana and disease resistant hybrids; (2) evaluation of the extent of somaclonal variation in plants regenerated from protoplasts; and (3)...

  17. Osmotic Water Permeability of Isolated Protoplasts. Modifications during Development1

    PubMed Central

    Ramahaleo, Tiana; Morillon, Raphaël; Alexandre, Joël; Lassalles, Jean-Paul

    1999-01-01

    A transference chamber was developed to measure the osmotic water permeability coefficient (Pos) in protoplasts 40 to 120 μm in diameter. The protoplast was held by a micropipette and submitted to a steep osmotic gradient created in the transference chamber. Pos was derived from the changes in protoplast dimensions, as measured using a light microscope. Permeabilities were in the range 1 to 1000 μm s−1 for the various types of protoplasts tested. The precision for Pos was ≤40%, and within this limit, no asymmetry in the water fluxes was observed. Measurements on protoplasts isolated from 2- to 5-d-old roots revealed a dramatic increase in Pos during root development. A shift in Pos from 10 to 500 μm s−1 occurred within less than 48 h. This phenomenon was found in maize (Zea mays), wheat (Triticum aestivum), and rape (Brassica napus) roots. These results show that early developmental processes modify water-transport properties of the plasma membrane, and that the transference chamber is adapted to the study of water-transport mechanisms in native membranes. PMID:10069827

  18. STABILIZATION OF PROTOPLASTS AND SPHEROPLASTS BY SPERMINE AND OTHER POLYAMINES

    PubMed Central

    Tabor, Celia W.

    1962-01-01

    Tabor, Celia W. (National Institute of Arthritis and Metabolic Diseases, Bethesda, Md.). Stabilization of protoplasts and spheroplasts by spermine and other polyamines. J. Bacteriol. 83:1101–1111. 1962.—Spermine (10−3m) or spermidine prevents lysis of lysozyme-produced protoplasts of Escherichia coli W, E. coli B, and Micrococcus lysodeikticus in hypotonic media. Spheroplasts prepared by the action of penicillin are also stabilized by these concentrations of spermine and spermidine, but the protection is not as complete. Streptomycin, polylysine, and Ca++ are also effective or partially effective stabilizers, but 1,4-diaminobutane, 1,5-diaminopentane, ornithine, Mg++, and monovalent cations have no protective action at 10−3m concentration, and only a slight effect at higher concentrations. The osmotic stability conferred on protoplasts by spermine is irreversible. However, the protective effect of polyamines against lysis is not accompanied by restoration of viability to lysozyme protoplasts. There is a marked reduction in the loss of ultra-violet-absorbing material from the protoplasts to the medium when 10−3m spermine is present. PMID:16561942

  19. Magnetic field exposure stiffens regenerating plant protoplast cell walls.

    PubMed

    Haneda, Toshihiko; Fujimura, Yuu; Iino, Masaaki

    2006-02-01

    Single suspension-cultured plant cells (Catharanthus roseus) and their protoplasts were anchored to a glass plate and exposed to a magnetic field of 302 +/- 8 mT for several hours. Compression forces required to produce constant cell deformation were measured parallel to the magnetic field by means of a cantilever-type force sensor. Exposure of intact cells to the magnetic field did not result in any changes within experimental error, while exposure of regenerating protoplasts significantly increased the measured forces and stiffened regenerating protoplasts. The diameters of intact cells or regenerating protoplasts were not changed after exposure to the magnetic field. Measured forces for regenerating protoplasts with and without exposure to the magnetic field increased linearly with incubation time, with these forces being divided into components based on the elasticity of synthesized cell walls and cytoplasm. Cell wall synthesis was also measured using a cell wall-specific fluorescent dye, and no changes were noted after exposure to the magnetic field. Analysis suggested that exposure to the magnetic field roughly tripled the Young's modulus of the newly synthesized cell wall without any lag.

  20. Perianth bottom-specific blue color development in Tulip cv. Murasakizuisho requires ferric ions.

    PubMed

    Shoji, Kazuaki; Miki, Naoko; Nakajima, Noriyuki; Momonoi, Kazumi; Kato, Chiharu; Yoshida, Kumi

    2007-02-01

    The entire flower of Tulipa gesneriana cv. Murasakizuisho is purple, except the bottom, which is blue. To elucidate the mechanism of the different color development in the same petal, we prepared protoplasts from the purple and blue epidermal regions and measured the flavonoid composition by HPLC, the vacuolar pH by a proton-selective microelectrode, and element contents by the inductively coupled plasma (ICP) method. Chemical analyses revealed that the anthocyanin and flavonol compositions in both purple and blue colored protoplasts were the same; delphinidin 3-O-rutinoside (1) and major three flavonol glycosides, manghaslin (2), rutin (3) and mauritianin (4). The vacuolar pH values of the purple and blue protoplasts were 5.5 and 5.6, respectively, without any significant difference. However, the Fe(3+) content in the blue protoplast was approximately 9.5 mM, which was 25 times higher than that in the purple protoplasts. We could reproduce the purple solution by mixing 1 with two equimolar concentrations of flavonol with lambda(vismax) = 539 nm, which was identical to that of the purple protoplasts. Furthermore, addition of Fe(3+) to the mixture of 1-4 gave the blue solution with lambda(vismax) = 615 nm identical to that of the blue protoplasts. We have established that Fe(3+) is essential for blue color development in the tulip.

  1. Regeneration of viable oil palm plants from protoplasts by optimizing media components, growth regulators and cultivation procedures.

    PubMed

    Masani, Mat Yunus Abdul; Noll, Gundula; Parveez, Ghulam Kadir Ahmad; Sambanthamurthi, Ravigadevi; Prüfer, Dirk

    2013-09-01

    Oil palm protoplasts are suitable as a starting material for the production of oil palm plants with new traits using approaches such as somatic hybridization, but attempts to regenerate viable plants from protoplasts have failed thus far. Here we demonstrate, for the first time, the regeneration of viable plants from protoplasts isolated from cell suspension cultures. We achieved a protoplast yield of 1.14×10(6) per gram fresh weight with a viability of 82% by incubating the callus in a digestion solution comprising 2% cellulase, 1% pectinase, 0.5% cellulase onuzuka R10, 0.1% pectolyase Y23, 3% KCl, 0.5% CaCl2 and 3.6% mannitol. The regeneration of protoplasts into viable plants required media optimization, the inclusion of plant growth regulators and the correct culture technique. Microcalli derived from protoplasts were obtained by establishing agarose bead cultures using Y3A medium supplemented with 10μM naphthalene acetic acid, 2μM 2,4-dichlorophenoxyacetic acid, 2μM indole-3-butyric acid, 2μM gibberellic acid and 2μM 2-γ-dimethylallylaminopurine. Small plantlets were regenerated from microcalli by somatic embryogenesis after successive subculturing steps in medium with limiting amounts of growth regulators supplemented with 200mg/l ascorbic acid. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  2. Effect of Proteolytic Enzymes on Transfection and Transformation of Streptococcus lactis Protoplasts †

    PubMed Central

    Woskow, Steven A.; Kondo, Jeffery K.

    1987-01-01

    With both chymotrypsin and mutanolysin used to form protoplasts, consistent transformation frequencies of 104 to 105 transformants and transfectants per μg of DNA were achieved. The procedure was used to transform protoplasts of Streptococcus cremoris CS224 at low frequency (5 transformants per μg of DNA). Images PMID:16347474

  3. Improved efficiency of plant regeneration from protoplasts of eggplant Solanum melongena L.

    PubMed

    Guri, A; Izhar, S

    1984-12-01

    Eggplant (Solanum melongena L.) mesophyll protoplasts were obtained from in vitro growing plants of line 410 and cv. 'Classic'. Relatively high (15%) plating efficiency was achieved using petri dishes with alternate quadrants containing reservoir medium (R medium + 1% activated charcoal) and culture medium. Shoot regeneration occurred within 6 weeks following initiation of protoplast culture.

  4. The Plant Protoplast: A Useful Tool for Plant Research and Student Instruction

    ERIC Educational Resources Information Center

    Wagner, George J.; And Others

    1978-01-01

    A plant protoplast is basically a plant cell that lacks a cell wall. This article outlines some of the ways in which protoplasts may be used to advance understanding of plant cell biology in research and student instruction. Topics include high efficiency experimental virus infection, organelle isolation, and osmotic effects. (Author/MA)

  5. Protoplast isolation and plant regeneration of guava (Psidium guajava L.) using experiments in mixture-amount design

    USDA-ARS?s Scientific Manuscript database

    A protocol was established for plant regeneration from leaf protoplasts of guava (Psidium guajava L.) using mixture-amount (concentration) experiments. A protoplast yield of 3.7 × 106 (viability > 90 percent) was obtained when 1 g leaf strips were digested in a solution of approximately 0.75 M osmot...

  6. The Lettuce infectious yellows virus (LIYV)-encoded P26 is associated with plasmalemma deposits within LIYV-infected cells

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Medina, V.; Sudarshana, M.R.; Tian, T.

    2005-03-15

    Cytological, immunological, and mutagenesis approaches were used to identify the viral factors associated with the formation of plasmalemma deposits (PLDs) in whole plants and protoplasts infected by Lettuce infectious yellows virus (LIYV). Transmission electron microscopy and immunogold labeling using polyclonal antibodies to four of the five LIYV RNA 2-encoded large proteins, capsid protein (CP), minor capsid protein (CPm), HSP70 homolog (HSP70h), and P59, showed specific labeling of LIYV virions or virion aggregates around the vesiculated membranous inclusions, but not PLDs in LIYV-infected Nicotiana benthamiana, Nicotiana clevelandii, Lactuca sativa, and Chenopodium murale plants, and Nicotiana tabacum protoplasts. In contrast, antibodies tomore » the RNA 2-encoded P26 showed specific labeling of PLDs but not virions in both LIYV-infected plants and protoplasts. Virion-like particles (VLPs) were seen in protoplasts infected by all LIYV RNA 2 mutants except for the CP (major capsid protein) mutant. PLDs were more difficult to find in protoplasts, but were seen in protoplasts infected by the CP and CPm mutants, but not in protoplasts infected by the P26, HSP70h, or P59 mutants. Interestingly, although the CPm mutant showed VLPs and PLDs, the PLDs did not show associated virions/virion-like particles as was always observed for PLDs seen in protoplasts infected by wild-type LIYV. Immunoblot analyses performed on purified LIYV virions showed that P26 was not detected with purified virions, but was detected in the cell wall, 1000 g and 30,000 g pellet fractions of LIYV-infected plants. These data suggest that P26 is associated with the LIYV-induced PLDs, and in contrast to the other RNA 2-encoded large proteins, P26 is not a virion protein.« less

  7. Penicillium ochrochloron MTCC 517 chitinase: An effective tool in commercial enzyme cocktail for production and regeneration of protoplasts from various fungi

    PubMed Central

    Patil, Nilambari S.; Jadhav, Jyoti P.

    2014-01-01

    Penicillium ochrochloron MTCC 517 is a potent producer of chitinolytic enzymes. Novozyme 234, traditional enzyme cocktail for protoplast generation is not available in the market. So, new enzyme cocktail is prepared for protoplast formation from various filamentous fungi which consists of 5 mg ml−1 lysing enzymes from Trichoderma harzianum, 0.06 mg ml−1 β-glucuronidase from Helix pomatia and 1 mg ml−1P. ochrochloron chitinase. The greatest number of protoplasts could be produced from most of the fungi in 0.8 M sorbitol and by incubation for about 2 h at 37 °C, but the number was decreased by incubation for more than 3 h. About twice as many protoplasts were produced from different species of fungi by involvement of P. ochrochloron chitinase than with combined commercial enzymes. PMID:25737658

  8. Penicillium ochrochloron MTCC 517 chitinase: An effective tool in commercial enzyme cocktail for production and regeneration of protoplasts from various fungi.

    PubMed

    Patil, Nilambari S; Jadhav, Jyoti P

    2015-03-01

    Penicillium ochrochloron MTCC 517 is a potent producer of chitinolytic enzymes. Novozyme 234, traditional enzyme cocktail for protoplast generation is not available in the market. So, new enzyme cocktail is prepared for protoplast formation from various filamentous fungi which consists of 5 mg ml(-1) lysing enzymes from Trichoderma harzianum, 0.06 mg ml(-1) β-glucuronidase from Helix pomatia and 1 mg ml(-1) P. ochrochloron chitinase. The greatest number of protoplasts could be produced from most of the fungi in 0.8 M sorbitol and by incubation for about 2 h at 37 °C, but the number was decreased by incubation for more than 3 h. About twice as many protoplasts were produced from different species of fungi by involvement of P. ochrochloron chitinase than with combined commercial enzymes.

  9. Content and Vacuole/Extravacuole Distribution of Neutral Sugars, Free Amino Acids, and Anthocyanin in Protoplasts 1

    PubMed Central

    Wagner, George J.

    1979-01-01

    Neutral sugar, free amino acid, and anthocyanin levels and vacuole/extravacuole distribution were determined for Hippeastrum and Tulipa petal and Tulipa leaf protoplasts. Glucose and fructose, the predominant neutral monosaccharides observed, were primarily vacuolar in location. Glutamine, the predominant free amino acid found, was primarily extravacuolar. γ-Methyleneglutamate was identified as a major constituent of Tulipa protoplasts. Qualitative characterization of Hippeastrum petal and vacuole organic acids indicated the presence of oxalic, malic, citric, and isocitric acids. Data are presented which indicate that vacuoles obtained by gentle osmotic shock of protoplasts in dibasic phosphate have good purity and retain their contents. Images PMID:16660921

  10. Protoplast Volume:Water Potential Relationship and Bound Water Fraction in Spinach Leaves 1

    PubMed Central

    Santakumari, Mane; Berkowitz, Gerald A.

    1989-01-01

    Methods used to estimate the (nonosmotic) bound water fraction (BWF) (i.e. apoplast water) of spinach (Spinacia oleracea L.) leaves were evaluated. Studies using three different methods of pressure/volume (P/V) curve construction all resulted in a similar calculation of BWF; approximately 40%. The theoretically derived BWF, and the water potential (Ψw)/relative water content relationship established from P/V curves were used to establish the relationship between protoplast (i.e. symplast) volume and Ψw. Another method of establishing the protoplast volume/Ψw relationship in spinach leaves was compared with the results from P/V curve experiments. This second technique involved the vacuum infiltration of solutions at a range of osmotic potentials into discs cut from spinach leaves. These solutions contained radioactively labeled H2O and sorbitol. This dual label infiltration technique allowed for simultaneous measurement of the total and apoplast volumes in leaf tissue; the difference yielded the protoplast volume. The dual label infiltration experiments and the P/V curve constructions both showed that below −1 megapascals, protoplast volume decreases sharply with decreasing water potential; with 50% reduction in protoplast volume occurring at −1.8 megapascals leaf water potential. PMID:16666983

  11. Measuring the Osmotic Water Permeability of the Plant Protoplast Plasma Membrane: Implication of the Nonosmotic Volume

    PubMed Central

    2010-01-01

    Starting from the original theoretical descriptions of osmotically induced water volume flow in membrane systems, a convenient procedure to determine the osmotic water permeability coefficient (Pos) and the relative nonosmotic volume (β) of individual protoplasts is presented. Measurements performed on protoplasts prepared from pollen grains and pollen tubes of Lilium longiflorum cv. Thunb. and from mesophyll cells of Nicotiana tabacum L. and Arabidopsis thaliana revealed low values for the osmotic water permeability coefficient in the range 5–20 μm · s−1 with significant differences in Pos, depending on whether β is considered or not. The value of β was determined using two different methods: by interpolation from Boyle-van’t Hoff plots or by fitting a solution of the theoretical equation for water volume flow to the whole volume transients measured during osmotic swelling. The values determined with the second method were less affected by the heterogeneity of the protoplast samples and were around 30% of the respective isoosmotic protoplast volume. It is therefore important to consider nonosmotic volume in the calculation of Pos as plant protoplasts behave as nonideal osmometers. PMID:17568979

  12. Genome shuffling improves production of the low-temperature alkalophilic lipase by Acinetobacter johnsonii.

    PubMed

    Wang, HaiKuan; Zhang, Jie; Wang, XiaoJie; Qi, Wei; Dai, YuJie

    2012-01-01

    The production of a low-temperature alkalophilic lipase from Acinetobacter johnsonii was improved using genome shuffling. The starting populations, obtained by UV irradiation and diethyl sulfate mutagenesis, were subjected to recursive protoplast fusion. The optimal conditions for protoplast formation and regeneration were 0.15 mg lysozyme/ml for 45 min at 37°C. The protoplasts were inactivated under UV for 20 min or heated at 60°C for 60 min and a fusant probability of ~98% was observed. The positive colonies were created by fusing the inactivated protoplasts. After two rounds of genome shuffling, one strain, F22, with a lipase activity of 7 U/ml was obtained.

  13. Dual-frequency dielectrophoretic levitation of Canola protoplasts.

    PubMed

    Kaler, K V; Xie, J P; Jones, T B; Paul, R

    1992-07-01

    A novel dual-frequency excitation technique is introduced which permits investigation of the low-frequency dispersion of Canola plant protoplasts using feedback-controlled dielectrophoretic levitation. The upper and intermediate frequency spectra obtained using the new technique are generally consistent with previous work. However, below some cross-over frequency f(OL), the protoplasts exhibit an apparent positive dielectrophoretic response that is not predicted by conventional theory. This cross-over frequency is linearly related to suspension conductivity, virtually independent of the suspension pH, and inversely proportional to the square of the cell radius. Examination of the complex Clausius-Mossotti polarization coefficient reveals that the observed positive dielectrophoretic response can not be accounted for in terms of Maxwell-Wagner polarization associated with a conventional layered model for the protoplast. The failure of straightforward enhancements to the protoplast model in explaining the low frequency behavior may indicate the presence of an electrophoretic contribution to the net observable force on the particle. To account for such fluid mechanical effects, it will be necessary to modify the existing dielectrophoretic force formulation.

  14. Cytoplasmic calcium levels in protoplasts from the cap and elongation zone of maize roots

    NASA Technical Reports Server (NTRS)

    Kiss, H. G.; Evans, M. L.; Johnson, J. D.

    1991-01-01

    Calcium has been implicated as a key component in the signal transduction process of root gravitropism. We measured cytoplasmic free calcium in protoplasts isolated from the elongation zone and cap of primary roots of light-grown, vertically oriented seedlings of Zea mays L. Protoplasts were loaded with the penta-potassium salts of fura-2 and indo-1 by incubation in acidic solutions of these calcium indicators. Loading increased with decreasing pH but the pH dependence was stronger for indo-1 than for fura-2. In the case of fura-2, loading was enhanced only at the lowest pH (4.5) tested. Dyes loaded in this manner were distributed predominantly in the cytoplasm as indicated by fluorescence patterns. As an alternative method of loading, protoplasts were incubated with the acetoxymethylesters of fura-2 and indo-1. Protoplasts loaded by this method exhibited fluorescence both in the cytoplasm and in association with various organelles. Cytoplasmic calcium levels measured using spectrofluorometry, were found to be 160 +/- 40 nM and 257 +/- 27 nM, respectively, in populations of protoplasts from the root cap and elongation zone. Cytoplasmic free calcium did not increase upon addition of calcium to the incubation medium, indicating that the passive permeability to calcium was low.

  15. Molecular characterization of intergeneric hybrid between Aspergillus oryzae and Trichoderma harzianum by protoplast fusion.

    PubMed

    Patil, N S; Patil, S M; Govindwar, S P; Jadhav, J P

    2015-02-01

    Protoplast fusion between Aspergillus oryzae and Trichoderma harzianum and application of fusant in degradation of shellfish waste. The filamentous chitinolytic fungal strains A. oryzae NCIM 1272 and T. harzianum NCIM 1185 were selected as parents for protoplast fusion. Viable protoplasts were released from fungal mycelium using enzyme cocktail containing 5 mg ml(-1) lysing enzymes from T. harzianum, 0.06 mg ml(-1) β-glucuronidase from Helix pomatia and 1 mg ml(-1) purified Penicillium ochrochloron chitinase in 0.8 mol l(-1) sorbitol as an osmotic stabilizer. Intergeneric protoplast fusion was carried out using 60% polyethylene glycol as a fusogen. At optimum conditions, the regeneration frequency of the fused protoplasts on colloidal chitin medium and fusion frequency were calculated. Fusant showed higher rate of growth pattern, chitinase activity and protein content than parents. Fusant formation was confirmed by morphological markers, viz. colony morphology and spore size and denaturation gradient gel electrophoresis (DGGE). This study revealed protoplast fusion between A. oryzae and T. harzianum significantly enhanced chitinase activity which ultimately provides potential strain for degradation of shellfish waste. Consistency in the molecular characterization results using DGGE is the major outcome of this study which can be emerged as a fundamental step in fusant identification. Now it is need to provide attention over effective chitin degradation to manage shrimp processing issues. In this aspect, ability of fusant to degrade shellfish waste efficiently in short incubation time revealed discovery of potential strain in the reclamation of seafood processing crustacean bio-waste. © 2014 The Society for Applied Microbiology.

  16. Establishment of transient gene expression systems in protoplasts from Liriodendron hybrid mesophyll cells

    PubMed Central

    Huo, Ailing; Chen, Zhenyu; Wang, Pengkai; Yang, Liming; Wang, Guangping; Wang, Dandan; Liao, Suchan; Cheng, Tielong; Chen, Jinhui; Shi, Jisen

    2017-01-01

    Liriodendron is a genus of the magnolia family comprised of two flowering tree species that produce hardwoods of great ecological and economic value. However, only a limited amount of genetic research has been performed on the Liriodendron genus partly because transient or stable transgenic trees have been difficult to produce. In general, transient expression systems are indispensable for rapid, high-throughput screening and systematic characterization of gene functions at a low cost; therefore, development of such a system for Liriodendron would provide a necessary step forward for research on Magnoliaceae and other woody trees. Herein, we describe an efficient and rapid protocol for preparing protoplasts from the leaf mesophyll tissue of a Liriodendron hybrid and an optimized system for polyethylene glycol–mediated transient transfection of the protoplasts. Because the leaves of the Liriodendron hybrid are waxy, we formulated an enzyme mix containing 1.5% (w/v) Cellulase R-10, 0.5% (w/v) Macerozyme R-10, and 0.1% (w/v) Pectolyase Y-23 to efficiently isolate protoplasts from the Liriodendron hybrid leaf mesophyll tissue in 3 h. We optimized Liriodendron protoplast transfection efficiency by including 20 μg plasmid DNA per 104 protoplasts, a transformation time of 20 min, and inclusion of 20% (w/v) polyethylene glycol 4000. After integrating the Liriodendron WOX1 gene into pJIT166-GFP to produce a WOX1-GFP fusion product and transfecting it into isolated protoplasts, LhWOX1-GFP was found to localize to the nucleus according to its green fluorescence. PMID:28323890

  17. Establishment of transient gene expression systems in protoplasts from Liriodendron hybrid mesophyll cells.

    PubMed

    Huo, Ailing; Chen, Zhenyu; Wang, Pengkai; Yang, Liming; Wang, Guangping; Wang, Dandan; Liao, Suchan; Cheng, Tielong; Chen, Jinhui; Shi, Jisen

    2017-01-01

    Liriodendron is a genus of the magnolia family comprised of two flowering tree species that produce hardwoods of great ecological and economic value. However, only a limited amount of genetic research has been performed on the Liriodendron genus partly because transient or stable transgenic trees have been difficult to produce. In general, transient expression systems are indispensable for rapid, high-throughput screening and systematic characterization of gene functions at a low cost; therefore, development of such a system for Liriodendron would provide a necessary step forward for research on Magnoliaceae and other woody trees. Herein, we describe an efficient and rapid protocol for preparing protoplasts from the leaf mesophyll tissue of a Liriodendron hybrid and an optimized system for polyethylene glycol-mediated transient transfection of the protoplasts. Because the leaves of the Liriodendron hybrid are waxy, we formulated an enzyme mix containing 1.5% (w/v) Cellulase R-10, 0.5% (w/v) Macerozyme R-10, and 0.1% (w/v) Pectolyase Y-23 to efficiently isolate protoplasts from the Liriodendron hybrid leaf mesophyll tissue in 3 h. We optimized Liriodendron protoplast transfection efficiency by including 20 μg plasmid DNA per 104 protoplasts, a transformation time of 20 min, and inclusion of 20% (w/v) polyethylene glycol 4000. After integrating the Liriodendron WOX1 gene into pJIT166-GFP to produce a WOX1-GFP fusion product and transfecting it into isolated protoplasts, LhWOX1-GFP was found to localize to the nucleus according to its green fluorescence.

  18. Highly efficient mesophyll protoplast isolation and PEG-mediated transient gene expression for rapid and large-scale gene characterization in cassava (Manihot esculenta Crantz).

    PubMed

    Wu, Jun-Zheng; Liu, Qin; Geng, Xiao-Shan; Li, Kai-Mian; Luo, Li-Juan; Liu, Jin-Ping

    2017-03-14

    Cassava (Manihot esculenta Crantz) is a major crop extensively cultivated in the tropics as both an important source of calories and a promising source for biofuel production. Although stable gene expression have been used for transgenic breeding and gene function study, a quick, easy and large-scale transformation platform has been in urgent need for gene functional characterization, especially after the cassava full genome was sequenced. Fully expanded leaves from in vitro plantlets of Manihot esculenta were used to optimize the concentrations of cellulase R-10 and macerozyme R-10 for obtaining protoplasts with the highest yield and viability. Then, the optimum conditions (PEG4000 concentration and transfection time) were determined for cassava protoplast transient gene expression. In addition, the reliability of the established protocol was confirmed for subcellular protein localization. In this work we optimized the main influencing factors and developed an efficient mesophyll protoplast isolation and PEG-mediated transient gene expression in cassava. The suitable enzyme digestion system was established with the combination of 1.6% cellulase R-10 and 0.8% macerozyme R-10 for 16 h of digestion in the dark at 25 °C, resulting in the high yield (4.4 × 10 7 protoplasts/g FW) and vitality (92.6%) of mesophyll protoplasts. The maximum transfection efficiency (70.8%) was obtained with the incubation of the protoplasts/vector DNA mixture with 25% PEG4000 for 10 min. We validated the applicability of the system for studying the subcellular localization of MeSTP7 (an H + /monosaccharide cotransporter) with our transient expression protocol and a heterologous Arabidopsis transient gene expression system. We optimized the main influencing factors and developed an efficient mesophyll protoplast isolation and transient gene expression in cassava, which will facilitate large-scale characterization of genes and pathways in cassava.

  19. Measurement of Mitochondrial Respiration in Isolated Protoplasts: Cytochrome and Alternative Pathways.

    PubMed

    Sunil, Bobba; Raghavendra, Agepati S

    2017-01-01

    The electron partitioning between COX and AOX pathways of mitochondria and their coordination is necessary to meet the energy demands as well as to maintain optimized redox status in plants under varying environmental conditions. The relative contribution of these two pathways to total respiration is an important measure during a given stress condition. We describe in detail the procedure that allows the measurement of the parameters of COX and AOX pathway of respiration in mesophyll protoplasts using Clark-type O 2 electrode. This chapter also lists the steps for rapid isolation procedure for mesophyll protoplasts from pea leaves. The advantages and limitations of the use of metabolic inhibitors and the protoplasts for measuring the respiration are also briefly discussed.

  20. Carbon transitions from either Calvin cycle or transitory starch to heteroglycans as revealed by (14) C-labeling experiments using protoplasts from Arabidopsis.

    PubMed

    Malinova, Irina; Steup, Martin; Fettke, Joerg

    2013-09-01

    Plants metabolize transitory starch by precisely coordinated plastidial and cytosolic processes. The latter appear to include the action of water-soluble heteroglycans (SHGin ) whose monosaccharide pattern is similar to that of apoplastic glycans (SHGex ) but, unlike SHGex , SHGin strongly interacts with glucosyl transferases. In this study, we analyzed starch metabolism using mesophyll protoplasts from wild-type plants and two knock-out mutants [deficient in the cytosolic transglucosidase, disproportionating isoenzyme 2 (DPE2) or the plastidial phosphoglucomutase (PGM1)] from Arabidopsis thaliana. Protoplasts prelabeled by photosynthetic (14) CO2 fixation were transferred to an unlabeled medium and were darkened or illuminated. Carbon transitions from the Calvin cycle or from starch to both SHGin and SHGex were analyzed. In illuminated protoplasts, starch turn-over was undetectable but darkened protoplasts continuously degraded starch. During illumination, neither the total (14) C content nor the labeling patterns of the sugar residues of SHGin were significantly altered but both the total amount and the labeling of the constituents of SHGex increased with time. In darkened protoplasts, the (14) C-content of most of the sugar residues of SHGin transiently and strongly increased and then declined. This effect was not observed in any SHGex constituent. In darkened DPE2-deficient protoplasts, none of the SHGin constituents exhibited an essential transient increase in labeling. In contrast, some residues of SHGin from the PGM1 mutant exhibited a transient increase in label but this effect significantly differed from that of the wild type. Two conclusions are reached: first, SHGin and SHGex exert different metabolic functions and second, SHGin is directly involved in starch degradation. © 2013 Scandinavian Plant Physiology Society.

  1. Protoplasts Obtained from Candida tropicalis Grown on Alkanes

    PubMed Central

    Lebeault, J. M.; Roche, B.; Duvnjak, Z.; Azoulay, E.

    1969-01-01

    A method for the preparation of protoplasts from Candida tropicalis cultivated on n-tetradecane is described. This essentially consists of replacing the mannitol-sorbitol solution of the classical helicase technique by 1 m magnesium sulfate and lowering the pH to 4.1 during incubation in the presence of helicase. The protoplasts thus prepared behave like intact cells and are capable of consuming oxygen in the presence of n-tetradecane, n-decane, 1-decanol, and glucose. Images PMID:5361212

  2. Surface Structure of Yeast Protoplasts

    PubMed Central

    Streiblová, Eva

    1968-01-01

    The fine structure of the yeast cell wall during protoplast formation was studied by means of phase-contrast microscopy and the freeze-etching technique. The freeze-etching results indicated that at least in some cases the entire wall substance was not removed from the surface of the protoplasts. After a treatment of 30 min to 3 hr with 2% snail enzymes, an innermost thin wall layer as well as remnants of the fibrillar middle layer sometimes could be demonstrated. Images PMID:4867751

  3. Plant regeneration from leaf protoplasts of Solanum torvum.

    PubMed

    Guri, A; Volokita, M; Sink, K C

    1987-07-01

    A protocol to obtain regenerated plants from protoplasts of Solanum torvum Sw a wild species of eggplant resistant to Verticillium wilt is reported. Leaf protoplasts were enzymatically isolated from six-week old seedlings grown in a controlled environment chamber. Protoplasts were plated on modified KM medium (0.4 M glucose)+(mg/l): 1.0 p-chlorophenoxyacetic acid (CPA)+1.0 naphthaleneacetic acid (NAA)+0.5 6-benzylaminopurine (BAP) and 0.02 abscisic acid (ABA). The protoplast density was 5×10(4) per ml with 5 ml placed in each of two quadrants in X-dishes (100×15 mm). The reservoir medium was modified KM+(mg/l): 0.1 NAA+0.5 BAP+0.1 M sucrose+0.1 M mannitol+0.6% washed agar+1% activated charcoal. Dishes were initially placed in the dark at 27°C. Protoplast division was initiated in 1-2 weeks and 4 weeks later p-calli were 1-3 mm. Plating efficiency was 11% when measured at 3 weeks. Six-week old p-calli were transferred individually onto Whatman No. 1 filter paper layered on modified KM (0.15 M sucrose)+mg/l: 2.0 indoleacetic acid (IAA)+2.0 zeatin+0.5% washed agar for 2 weeks. Subsequently, shoots occurred within 4 weeks at 70% efficiency on MS+30 g/l sucrose+2 mg/l zeatin. Shoots were rooted on half strength MS+10 g/l sucrose.

  4. Plant regeneration from cell suspension-derived protoplasts of Primula malacoides and Primula obconica.

    PubMed

    Mizuhiro, M; Kenichi, Y; Ito, K; Kadowaki, S; Ohashi, H; Mii, M

    2001-05-01

    Protoplasts were isolated from cell suspension cultures of Primula malacoides cv. 'Lovely Tokyo' and P. obconica cv. 'Aalsmeer Giant White'. P. obconica protoplasts were embedded in 0.1% (w/v) gellan gum-solidified discs comprising MS medium supplemented with 3 mg/l of 2,4-D or picloram, 0.1 mg/l of zeatin, 0.2 M glucose and 0.2 M mannitol, and surrounded by a liquid medium of the same composition except for the addition of 0.1% (w/v) activated charcoal. The protoplasts formed visible colonies, which were transferred to the regeneration medium containing 30 g/l of sucrose, 0.1 mg/l of picloram and 2 mg/l of zeatin for shoot induction. P. malacoides protoplasts formed visible colonies when cultured in disc culture using 0.1% (w/v) gellan gum-solidified MS medium containing 5 mg/l of 2,4-D, 1 mg/l of NAA, 0.1 mg/l of zeatin and 0.4 M glucose. Small calli were transferred to MS medium supplemented with 5 mg/l of zeatin for shoot regeneration. The shoots of both species readily rooted on plant growth regulator-free 1/2 MS medium and successfully acclimatized to greenhouse conditions. The protoplast-derived plants showed some alterations in morphological characteristics from those of the in-vitro-germinated control plants.

  5. Cellular distribution of calmodulin and calmodulin-binding proteins in Vicia faba L

    NASA Technical Reports Server (NTRS)

    Ling, V.; Assmann, S. M.

    1992-01-01

    The distribution of calmodulin (CaM) and CaM-binding proteins within Vicia faba was investigated. Both CaM and CaM-binding proteins were found to be differentially distributed among organs, tissues, and protoplast types. CaM levels, on a per protein basis, were found to be the highest in leaf epidermis, containing 3-fold higher levels of CaM than in total leaf. Similarly, guard cell and epidermal cell protoplasts were also found to have higher levels of CaM than mesophyll cell protoplasts. 125I-CaM blot overlay assays were performed to qualitatively examine CaM-binding proteins in these protoplast types as well as in whole tissues and organs. CaM-binding proteins with Mr 52,000, 78,000, and 115,000 were common in all metabolically active plant parts. Unique CaM-binding protein bands were detected in guard cell protoplasts (Mr 39,000, 88,000), stems (Mr 45,000, 60,000, 64,000), and roots (Mr 62,000), suggesting the presence of specialized CaM-dependent processes in these cells and organs.

  6. Dual-frequency dielectrophoretic levitation of Canola protoplasts

    PubMed Central

    Kaler, Karan V. I. S.; Xie, Jing-Ping; Jones, Thomas B.; Paul, Reginald

    1992-01-01

    A novel dual-frequency excitation technique is introduced which permits investigation of the low-frequency dispersion of Canola plant protoplasts using feedback-controlled dielectrophoretic levitation. The upper and intermediate frequency spectra obtained using the new technique are generally consistent with previous work. However, below some cross-over frequency fOL, the protoplasts exhibit an apparent positive dielectrophoretic response that is not predicted by conventional theory. This cross-over frequency is linearly related to suspension conductivity, virtually independent of the suspension pH, and inversely proportional to the square of the cell radius. Examination of the complex Clausius-Mossotti polarization coefficient reveals that the observed positive dielectrophoretic response can not be accounted for in terms of Maxwell-Wagner polarization associated with a conventional layered model for the protoplast. The failure of straightforward enhancements to the protoplast model in explaining the low frequency behavior may indicate the presence of an electrophoretic contribution to the net observable force on the particle. To account for such fluid mechanical effects, it will be necessary to modify the existing dielectrophoretic force formulation. PMID:19431842

  7. Nuclear RNA quantification in protoplast cell-cycle phases.

    PubMed

    Bergounioux, C; Perennes, C; Brown, S C; Gadal, P

    1988-01-01

    Using acridine orange staining and flow cytometry the DNA and RNA levels (arbitrary units) of individual cells may be established. Here, this method has been applied to nuclei isolated from plant protoplasts during culture. The specificity of the technique has been validated for such plant material; ribonuclease markedly reduced nuclear staining without modifying the DNA histogram; ribonuclease inhibitor prevented the action of released cell nucleases; and protoplasts cultivated with actinomycin D did not synthesize RNA. First RNA synthesis was evident 18 h after Petunia hybrida protoplasts had been put into culture. An increase of RNA above a critical level was required for cells to be able to initiate DNA replication from G1, termed G1B. G2 nuclei had an RNA:DNA ratio similar to that of G1 nuclei.

  8. Plant regeneration from haploid cell suspension-derived protoplasts of Mediterranean rice (Oryza sativa L. cv. Miara).

    PubMed

    Guiderdoni, E; Chaïr, H

    1992-11-01

    More than 750 plants were regenerated from protoplasts isolated from microspore callus-derived cell suspensions of the Mediterranean japonica rice Miara, using a nurse-feeder technique and N6-based culture medium. The mean plating efficiency and the mean regeneration ability of the protocalluses were 0.5% and 49% respectively. Flow cytometric evaluation of the DNA contents of 7 month old-cell and protoplast suspensions showed that they were still haploid. Contrastingly, the DNA contents of leaf cell nuclei of the regenerated protoclones ranged from 1C to 5C including 60% 2C plants. This was consistent with the morphological type and the fertility of the mature plants. These results and the absence of chimeric plants suggest that polyploidization occurred during the early phase of protoplast culture.

  9. [Establishment and optimization of systems for protoplasts isolation of soybean and chickpea that used in subcellular location].

    PubMed

    Shu, Yingjie; Huang, Liyan; Chen, Ming; Tao, Yuan; Wang, Zhankui; Ma, Hao

    2017-06-25

    Young leaves of Kabuli chickpea as well as soybean Xiangdou No.3, which are the current plants that studied in our laboratory were selected as materials. Effects on protoplasts yield and survival rate of different enzyme combination, concentration of D-Mannitol in enzyme combinations, pH of enzyme combinations and enzymolysis time are detected. The results showed that, the best condition for Xiangdou No.3 leaf protoplasts isolation is to rotate the cut materials for 6 hours in enyzme solution under temperature of 27 ℃ and rotate speed of 45 r/min for 6 h. Onozuka R-10 (0.5%), Hemicellulase (0.8%), Macerozyme R-10 (0.8%) in combination with Pectolyase Y-23 (0.4%) dissolving in CPW solution with MES (0.1%) and Mannitol (10%), pH 6.0 was found best for protoplasts isolation of Xiangdou No.3 leaves.The best condition for protoplasts isolation of Kabuli chickpea is to put the cut materials into enzymatic hydrolysate enzymolyse for 7 to 8 hours under temperature of 27 ℃ and rotate speed of 45 r/min on water bath shaker, the optimum combination of enzyme consists of Onozuka R-10 (0.5%), Hemicellulase (0.8%), Macerozyme R-10 (0.8%), MES (0.1%) and Mannitol (10%) dissolved in CPW solution with pH 4.8. The protoplasts prepared with the methods above are used in subcellular location and the effects show well.

  10. Efficient targeted multiallelic mutagenesis in tetraploid potato (Solanum tuberosum) by transient CRISPR-Cas9 expression in protoplasts.

    PubMed

    Andersson, Mariette; Turesson, Helle; Nicolia, Alessandro; Fält, Ann-Sofie; Samuelsson, Mathias; Hofvander, Per

    2017-01-01

    Altered starch quality with full knockout of GBSS gene function in potato was achieved using CRISPR-Cas9 technology, through transient transfection and regeneration from isolated protoplasts. Site-directed mutagenesis (SDM) has shown great progress in introducing precisely targeted mutations. Engineered CRISPR-Cas9 has received increased focus compared to other SDM techniques, since the method is easily adapted to different targets. Here, we demonstrate that transient application of CRISPR-Cas9-mediated genome editing in protoplasts of tetraploid potato (Solanum tuberosum) yielded mutations in all four alleles in a single transfection, in up to 2 % of regenerated lines. Three different regions of the gene encoding granule-bound starch synthase (GBSS) were targeted under different experimental setups, resulting in mutations in at least one allele in 2-12 % of regenerated shoots, with multiple alleles mutated in up to 67 % of confirmed mutated lines. Most mutations resulted in small indels of 1-10 bp, but also vector DNA inserts of 34-236 bp were found in 10 % of analysed lines. No mutations were found in an allele diverging one bp from a used guide sequence, verifying similar results found in other plants that high homology between guide sequence and target region near the protospacer adjacent motif (PAM) site is essential. To meet the challenge of screening large numbers of lines, a PCR-based high-resolution fragment analysis method (HRFA) was used, enabling identification of multiple mutated alleles with a resolution limit of 1 bp. Full knockout of GBSS enzyme activity was confirmed in four-allele mutated lines by phenotypic studies of starch. One remaining wild-type (WT) allele was shown sufficient to maintain enough GBSS enzyme activity to produce significant amounts of amylose.

  11. Early Studies on Protoplast Isolation of Ludisia discolor, A Wild Orchid

    PubMed Central

    Poobathy, Ranjetta; Zakaria, Rahmad; Hamzah, Syed Mohd. Edzham Syed; Subramaniam, Sreeramanan

    2016-01-01

    The terrestrial Ludisia discolor, also referred to as the jewel orchid is prized for the quality of its leaves. L. discolor is known as a medicinal herb and is touted for its heat- and pathogen-resisting qualities. L. discolor is valuable in the production of both flavonoids and anthocyanins, antioxidants that are exalted in the health industry. Plant cell cultures have emerged as alternative sources of anthocyanin production. Plant protoplast cultures are used frequently in transient gene expression studies and in the establishment of callus and cell suspension cultures. Benefits of plant protoplast system include similarity to cells found in plant tissues, reproduction under controlled conditions, and prevention of masking of stress responses to previous handling techniques. A study was conducted to assess the amenability of the stem and leaves of L. discolor to protoplast isolation. The stem and leaf segments were weighed, sliced into thin layers, immersed in a digestion medium, washed and then cultured onto a recovery medium. Results indicated that the production of plant protoplasts from L. discolor may be viewed as an alternative in the generation of cell cultures and ultimately in the production of anthocyanins from the cell cultures. PMID:27965736

  12. Isolation, culture, and plant regeneration from Echinacea purpurea protoplasts.

    PubMed

    Pan, Zeng-guang; Liu, Chun-zhao; Murch, Susan I; Saxena, Praveen K

    2006-01-01

    A plant regeneration system from the isolated protoplasts of Echinacea purpurea L. using an alginate solid/liquid culture is described in the chapter. Viable protoplasts were isolated rom 100 mg of young leaves of 4-wk-old seedlings in an isolation mixture containing 1.0% cellulase Onozuka R-10, 0.5% pectinase, and 0.3 mol/L mannitol. After isolation and purification, the mesophyll protoplasts were embedded into 0.6% Na-alginate at the density 1 x 10(-5) mL and cultured in modified Murashige and Skoog (MS) culture medium supplemented with 0.3 mol/L sucrose, 2.5 micromol/L benzylaminopurine (BA), and 5.0 micromol/L 2,4-dichlorophenoxyacetic acid (2,4-D). The visible colonies were present after 4 wk of culture. The protoplast-derived clones were transferred onto gellan gum-solidified basal medium supplemented with 1.0 micromol/L BA and 2.0 micromol/L indole-3-butyric acid (IBA) and formed compact and green calli. Shoot development was achieved by subculturing the calli onto the same basal medium supplemented with 5.0 micromol/L BA and 2.0 micromol/L IBA. Further subculture onto basal medium resulted in the regeneration of complete plantlets.

  13. Early Studies on Protoplast Isolation of Ludisia discolor, A Wild Orchid.

    PubMed

    Poobathy, Ranjetta; Zakaria, Rahmad; Hamzah, Syed Mohd Edzham Syed; Subramaniam, Sreeramanan

    2016-11-01

    The terrestrial Ludisia discolor , also referred to as the jewel orchid is prized for the quality of its leaves. L. discolor is known as a medicinal herb and is touted for its heat- and pathogen-resisting qualities. L. discolor is valuable in the production of both flavonoids and anthocyanins, antioxidants that are exalted in the health industry. Plant cell cultures have emerged as alternative sources of anthocyanin production. Plant protoplast cultures are used frequently in transient gene expression studies and in the establishment of callus and cell suspension cultures. Benefits of plant protoplast system include similarity to cells found in plant tissues, reproduction under controlled conditions, and prevention of masking of stress responses to previous handling techniques. A study was conducted to assess the amenability of the stem and leaves of L. discolor to protoplast isolation. The stem and leaf segments were weighed, sliced into thin layers, immersed in a digestion medium, washed and then cultured onto a recovery medium. Results indicated that the production of plant protoplasts from L. discolor may be viewed as an alternative in the generation of cell cultures and ultimately in the production of anthocyanins from the cell cultures.

  14. The use of flow cytometry to monitor chitin synthesis in regenerating protoplasts of Candida albicans.

    PubMed

    Hector, R F; Braun, P C; Hart, J T; Kamarck, M E

    1990-01-01

    Flow cytometry was used to monitor chitin synthesis in regenerating protoplasts of the yeast Candida albicans. Comparisons of cells stained with Calcofluor White, a fluorochrome with known affinity for chitin, and cells incubated in the presence of N-[3H]-acetylglucosamine, the precursor substrate for chitin, showed a linear relationship between fluorescence and incorporation of label over time. Changes in both the fluorescence and light scatter of regenerating protoplasts treated with inhibitors of fungal chitin synthase were also quantitated by flow cytometry.

  15. Aluminum ions induce oat protoplasts to produce an extracellular (1 yields 3). beta. -D-glucan

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Schaeffer, H.J.; Walton, J.D.

    1990-09-01

    Aluminum chloride induced mesophyll protoplasts of oat (Avena sativa) to produce an extracellular polysaccharide (EPS). EPS induced by AlCl{sub 3} appeared identical to that produced in response to the phytotoxin victorin. Al ions at 1 millimolar were toxic to protoplasts, but maximum EPS production occurred at a sublethal concentration of 200 micromolar, assayed at pH 6.0. As measured by incorporation of ({sup 14}C)glucose, AlCl{sub 3} stimulated EPS production 10- to 15-fold. Pretreatment of protoplasts with cycloheximide prevented EPS production but not cell death in response to AlCl{sub 3}, indicating that protein synthesis was necessary for EPS production but not formore » the phytotoxicity of Al ions. The trivalent salts of Y, Yb, Gd, and In also induced EPS production but those of Sc, Fe, Ga, Cr, and La did not. Mesophyll protoplasts from an acid-soil tolerant oat cultivar produced less EPS in response to AlCl{sub 3} than the acid-soil sensitive cultivar Fla 501. EPS was also produced by wheat (Triticum aestivum) and barley (Hordeum vulgare) protoplasts in response to AlCl{sub 3}. An Al-tolerant cultivar of wheat, Atlas, produced less EPS than an Al-sensitive cultivar, Scout, but an Al-tolerant cultivar of barley, Dayton, produced more than the Al-sensitive cultivar Kearney. Therefore, production of EPS by protoplasts in response to Al ions did not appear to be related to Al ion tolerance at the level of whole plants. EPS fluoresced in the presence of Calcofluor and Sirofluor and was degraded by purified laminarinase ((1{yields}3){beta}-D-glucanase) but did not pectinase (polygalacturonase). EPS was composed solely of glucose in 1{yields}3 linkages; hence it is a (1{yields}3){beta}-D-glucan (callose).« less

  16. Somatic hybridization in Citrus: navel orange (C. sinensis Osb.) and grapefruit (C. paradisi Macf.).

    PubMed

    Ohgawara, T; Kobayashi, S; Ishii, S; Yoshinaga, K; Oiyama, I

    1989-11-01

    Protoplasts of navel orange, isolated from embryogenic nucellar cell suspension culture, were fused with protoplasts of grapefruit isolated from leaf tissue. The fusion products were cultured in the hormone-free medium containing 0.6 M sucrose. Under the culture conditions, somatic embryogenesis of navel orange protoplasts was suppressed, while cell division of grapefruit mesophyll protoplasts was not induced. Six embryoids were obtained and three lines regenerated to complete plants through embryogenesis. Two of the regenerated lines exhibited intermediate morphological characteristics of the parents in the leaf shape. Chromosome counts showed that these regenerated plants had expected 36 chromosomes (2n=2x=18 for each parent). The rDNA analysis using biotin-labeled rRNA probes confirmed the presence of genomes from both parents in these plants. This somatic hybridization system would be useful for the practical Citrus breeding.

  17. Protoplast fusion enhances lignocellulolytic enzyme activities in Trichoderma reesei.

    PubMed

    Cui, Yu-xiao; Liu, Jia-jing; Liu, Yan; Cheng, Qi-yue; Yu, Qun; Chen, Xin; Ren, Xiao-dong

    2014-12-01

    Protoplast fusion was used to obtain a higher production of lignocellulolytic enzymes with protoplast fusion in Trichoderma reesei. The fusant strain T. reesei JL6 was obtained from protoplast fusion from T. reesei strains QM9414, MCG77, and Rut C-30. Filter paper activity of T. reesei JL6 increased by 18% compared with that of Rut C-30. β-Glucosidase, hemicellulase and pectinase activities of T. reesei JL6 were also higher. The former activity was 0.39 Uml(-1), while those of QM9414, MCG77, and Rut C-30 were 0.13, 0.11, and 0.16 Uml(-1), respectively. Pectinase and hemicellulase activities of JL6 were 5.4 and 15.6 Uml(-1), respectively, which were slightly higher than those of the parents. The effects of corn stover and wheat bran carbon sources on the cellulase production and growth curve of T. reesei JL6 were also investigated.

  18. Secretory production of cell wall components by Saccharomyces cerevisiae protoplasts in static liquid culture.

    PubMed

    Aoyagi, Hideki; Ishizaka, Mikiko; Tanaka, Hideo

    2012-04-01

    When protoplasts of Saccharomyces cerevisiae T7 and IFO 0309 are cultured in a static liquid culture at 2.5 × 10(6) protoplasts/ml, cell wall regeneration does not occur and cell wall components (CWC) are released into the culture broth. By using a specialized fluorometer, the concentrations of CWC could be measured on the basis of the fluorescence intensity of the CWC after staining with Fluostain I. The inoculum concentration, pH, and osmotic pressure of the medium were important factors for the production of CWC in culture. Under optimal culture conditions, S. cerevisiae T7 protoplasts produced 0.91 mg/ml CWC after 24 h. The CWC induced the tumor necrosis factor-α production about 1.3 times higher than that of the commercially available β-1,3/1,6-glucan from baker's yeast cells.

  19. PREPARATION AND REGENERATION OF PROTOPLASTS OF COLLETOTRICHUM GLEOSPORIODES F. SP. AESCHYNOMENE

    EPA Science Inventory

    Protoplasts were produced from conidia of Colletotrichum gloesporioides f. sp. aeschynomene, a fungal plant pathogen of Aeschynomene virginica, during treatment with Novozym 234 or a mixture of chitinase and B-glucuronidase after pretreatment with 2-mercaptoethanol. rotoplasts we...

  20. Transformation of Streptococcus lactis Protoplasts by Plasmid DNA †

    PubMed Central

    Kondo, Jeffery K.; McKay, Larry L.

    1982-01-01

    Polyethylene glycol-treated protoplasts prepared from Streptococcus lactis LM3302, a lactose-negative (Lac−) derivative of S. lactis ML3, were transformed to lactose-fermenting ability by a transductionally shortened plasmid (pLM2103) coding for lactose utilization. Images PMID:16346019

  1. Betaine synthesis in chenopods: localization in chloroplasts

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hanson, A.D.; May A.M.; Grumet, R.

    1985-06-01

    Plants from several families (Chenopodiaceae, Gramineae, Compositae) accumulate betaine (glycine betaine) in response to salt or water stress via the pathway: choline betainal (betaine aldehyde) betaine. Betaine accumulation is probably a metabolic adaptation to stress. Intact protoplasts from leaves of spinach (Spinacia oleracea) oxidized ( UC)choline to betainal and betaine, as did protoplast lysates. Upon differential centrifugation, the ( UC)choline-oxidizing activity of lysates sedimented with chloroplasts. Chloroplasts purified from protoplast lysates by a Percoll cushion procedure retained strong ( UC)choline-oxidizing activity, although the proportion of the intermediate, ( UC)betainal, in the reaction products was usually higher than for protoplasts. Isolatedmore » chloroplasts also readily oxidized ( UC)betainal to betaine. Light increased the oxidation of both ( UC)choline and ( UC)betainal by isolated chloroplasts. Similar results were obtained with another chenopod (Beta vulgaris) but not with pea (Pisum sativum), a species that accumulates no betaine. The chloroplast site for betaine synthesis in chenopods contrasts with the mitochondrial site in mammals.« less

  2. Cloning of Sucrose:Sucrose 1-Fructosyltransferase from Onion and Synthesis of Structurally Defined Fructan Molecules from Sucrose1

    PubMed Central

    Vijn, Irma; van Dijken, Anja; Lüscher, Marcel; Bos, Antoine; Smeets, Edward; Weisbeek, Peter; Wiemken, Andres; Smeekens, Sjef

    1998-01-01

    Sucrose (Suc):Suc 1-fructosyltransferase (1-SST) is the key enzyme in plant fructan biosynthesis, since it catalyzes de novo fructan synthesis from Suc. We have cloned 1-SST from onion (Allium cepa) by screening a cDNA library using acid invertase from tulip (Tulipa gesneriana) as a probe. Expression assays in tobacco (Nicotiana plumbaginifolia) protoplasts showed the formation of 1-kestose from Suc. In addition, an onion acid invertase clone was isolated from the same cDNA library. Protein extracts of tobacco protoplasts transformed with this clone showed extensive Suc-hydrolyzing activity. Conditions that induced fructan accumulation in onion leaves also induced 1-SST mRNA accumulation, whereas the acid invertase mRNA level decreased. Structurally different fructan molecules could be produced from Suc by a combined incubation of protein extract of protoplasts transformed with 1-SST and protein extract of protoplasts transformed with either the onion fructan:fructan 6G-fructosyltransferase or the barley Suc:fructan 6-fructosyltransferase. PMID:9701606

  3. Plant regeneration from protoplasts ofVicia narbonensis via somatic embryogenesis and shoot organogenesis.

    PubMed

    Tegeder, M; Kohn, H; Nibbe, M; Schieder, O; Pickardt, T

    1996-11-01

    Protoplasts ofVicia narbonensis isolated from epicotyls and shoot tips of etiolated seedlings were embedded in 1.4% sodium-alginate at a final density of 2.5×10(5) protoplasts/ml and cultivated in Kao and Michayluk-medium containing 0.5 mg/I of each of 2,4- dichlorophenoxyacetic acid, naphthylacetic acid and 6 -benzylaminopurine. A division frequency of 36% and a plating efficiency of 0.40-0.5% were obtained. Six weeks after embedding, protoplast-derived calluses were transferred onto gelrite-solidified Murashige and Skoog-media containing various growth regulators. Regeneration of plants was achieved via two morphologically distinguishable pathways. A two step protocol (initially on medium with a high auxin concentration followed by a culture phase with lowered auxin amount) was used to regenerate somatic embryos, whereas cultivation on medium containing thidiazuron and naphthylacetic acid resulted in shoot morphogenesis. Mature plants were recovered from both somatic embryos as well as from thidiazuron-induced shoots.

  4. Purified isolation of vacuoles from Sedum alfredii leaf-derived protoplasts.

    PubMed

    Gao, Xiao-Yu; Liao, Xing-Cheng; Wu, Ruo-Lai; Liu, Ting; Wang, Hai-Xing; Lu, Ling-Li

    This study aims to develop a method for isolating and purifying protoplasts/vacuoles from fresh leaves of the Cd hyperaccumulator plant species, Sedum alfredii. The results revealed that preheating cellulase and macerozyme at 50 °C for 5 min significantly accelerated the cell wall degradation. For the most optimal conditions for mesophyll protoplast isolation, the mixture of fresh leaves and cell lysates was followed by a 2-h-long vibration. The protoplast lysate for vacuole isolation was diluted, and 0.675 mmol/L was identified as the most appropriate 3-[(3-cholamidopropyl) dimethylammonio]-1-propanesulfonic acid (CHAPS) level, in which S. alfredii large vacuoles are characterized by a high metal and malic acid content. For the best vacuole purification results, we established that 0.8 mol/L was the most optimal mannitol level in the vacuole buffer in terms of vacuole protection during centrifugation, whereas a Ficoll concentration of 0.10 g/ml was adopted in the density-gradient centrifugation.

  5. Intergeneric somatic hybrid plants of Citrus sinensis cv. Hamlin and Poncirus trifoliata cv. Flying Dragon.

    PubMed

    Grosser, J W; Gmitter, F G; Chandler, J L

    1988-01-01

    Intergeneric somatic hybrid plants between 'Hamlin' sweet orange [Citrus sinensis (L.) Osbeck] and 'Flying Dragon' trifoliate orange (Poncirus trifoliata Raf.) were regenerated following protoplast fusion. 'Hamlin' protoplasts, isolated from an habituated embryogenic suspension culture, were fused chemically with 'Flying Dragon' protoplasts isolated from juvenile leaf tissue. The hybrid selection scheme was based on complementation of the regenerative ability of the 'Hamlin' protoplasts with the subsequent expression of the trifoliate leaf character of 'Flying Dragon.' Hybrid plants were regenerated via somatic embryogenesis and multiplied organogenically. Hybrid morphology was intermediate to that of the parents. Chromosome counts indicated that the hybrids were allotetraploids (2n=4x=36). Malate dehydrogenase (MDH) isozyme patterns confirmed the hybrid nature of the regenerated plants. These genetically unique somatic hybrid plants will be evaluated for citrus rootstock potential. The cell fusion, selection, and regeneration scheme developed herein should provide a general means to expand the germplasm base of cultivated Citrus by intergeneric hybridization with related sexually incompatible genera.

  6. Production of a full-length infectious GFP-tagged cDNA clone of Beet mild yellowing virus for the study of plant-polerovirus interactions.

    PubMed

    Stevens, Mark; Viganó, Felicita

    2007-04-01

    The full-length cDNA of Beet mild yellowing virus (Broom's Barn isolate) was sequenced and cloned into the vector pLitmus 29 (pBMYV-BBfl). The sequence of BMYV-BBfl (5721 bases) shared 96% and 98% nucleotide identity with the other complete sequences of BMYV (BMYV-2ITB, France and BMYV-IPP, Germany respectively). Full-length capped RNA transcripts of pBMYV-BBfl were synthesised and found to be biologically active in Arabidopsis thaliana protoplasts following electroporation or PEG inoculation when the protoplasts were subsequently analysed using serological and molecular methods. The BMYV sequence was modified by inserting DNA that encoded the jellyfish green fluorescent protein (GFP) into the P5 gene close to its 3' end. A. thaliana protoplasts electroporated with these RNA transcripts were biologically active and up to 2% of transfected protoplasts showed GFP-specific fluorescence. The exploitation of these cDNA clones for the study of the biology of beet poleroviruses is discussed.

  7. Transposition of a Ds element from a plasmid into the plant genome in Nicotiana plumbaginifolia protoplast-derived cells.

    PubMed

    Houba-Hérin, N; Domin, M; Pédron, J

    1994-07-01

    Nicotiana plumbaginifolia haploid protoplasts were co-transformed with two plasmids, one with a NPT-II/Ds element and one with a gene encoding an amino-terminal truncated Ac transposase. It is shown that Ds can efficiently transpose from extrachromosomal DNA to N. plumbaginifolia chromosomes when the Ac transposase gene is present in trans. Ds has been shown to have transposed into the plant genome in a limited number of copies (1.9 copies per genome), for 21/32 transgenic lines tested. The flanking sequences present in the original plasmid are missing in these 21 plants. In only two of 21 plants was part of the transposase construct integrated. By segregation analysis of transgenic progeny, Ds was shown to be present in the heterozygous state in 10 lines even though haploid protoplasts had been originally transformed. This observation could indicate that integration occurred after or during DNA replication that leads to protoplast diploidization.

  8. Protoplast isolation, transient transformation of leaf mesophyll protoplasts and improved Agrobacterium-mediated leaf disc infiltration of Phaseolus vulgaris: tools for rapid gene expression analysis.

    PubMed

    Nanjareddy, Kalpana; Arthikala, Manoj-Kumar; Blanco, Lourdes; Arellano, Elizabeth S; Lara, Miguel

    2016-06-24

    Phaseolus vulgaris is one of the most extensively studied model legumes in the world. The P. vulgaris genome sequence is available; therefore, the need for an efficient and rapid transformation system is more imperative than ever. The functional characterization of P. vulgaris genes is impeded chiefly due to the non-amenable nature of Phaseolus sp. to stable genetic transformation. Transient transformation systems are convenient and versatile alternatives for rapid gene functional characterization studies. Hence, the present work focuses on standardizing methodologies for protoplast isolation from multiple tissues and transient transformation protocols for rapid gene expression analysis in the recalcitrant grain legume P. vulgaris. Herein, we provide methodologies for the high-throughput isolation of leaf mesophyll-, flower petal-, hypocotyl-, root- and nodule-derived protoplasts from P. vulgaris. The highly efficient polyethylene glycol-mannitol magnesium (PEG-MMG)-mediated transformation of leaf mesophyll protoplasts was optimized using a GUS reporter gene. We used the P. vulgaris SNF1-related protein kinase 1 (PvSnRK1) gene as proof of concept to demonstrate rapid gene functional analysis. An RT-qPCR analysis of protoplasts that had been transformed with PvSnRK1-RNAi and PvSnRK1-OE vectors showed the significant downregulation and ectopic constitutive expression (overexpression), respectively, of the PvSnRK1 transcript. We also demonstrated an improved transient transformation approach, sonication-assisted Agrobacterium-mediated transformation (SAAT), for the leaf disc infiltration of P. vulgaris. Interestingly, this method resulted in a 90 % transformation efficiency and transformed 60-85 % of the cells in a given area of the leaf surface. The constitutive expression of YFP further confirmed the amenability of the system to gene functional characterization studies. We present simple and efficient methodologies for protoplast isolation from multiple P. vulgaris tissues. We also provide a high-efficiency and amenable method for leaf mesophyll transformation for rapid gene functional characterization studies. Furthermore, a modified SAAT leaf disc infiltration approach aids in validating genes and their functions. Together, these methods help to rapidly unravel novel gene functions and are promising tools for P. vulgaris research.

  9. Efficient gusA transient expression in Porphyra yezoensis protoplasts mediated by endogenous beta-tubulin flanking sequences

    NASA Astrophysics Data System (ADS)

    Gong, Qianhong; Yu, Wengong; Dai, Jixun; Liu, Hongquan; Xu, Rifu; Guan, Huashi; Pan, Kehou

    2007-01-01

    Endogenous tubulin promoter has been widely used for expressing foreign genes in green algae, but the efficiency and feasibility of endogenous tubulin promoter in the economically important Porphyra yezoensis (Rhodophyta) are unknown. In this study, the flanking sequences of beta-tubulin gene from P. yezoensis were amplified and two transient expression vectors were constructed to determine their transcription promoting feasibility for foreign gene gusA. The testing vector pATubGUS was constructed by inserting 5'-and 3'-flanking regions ( Tub5' and Tub3') up-and down-stream of β-glucuronidase (GUS) gene ( gusA), respectively, into pA, a derivative of pCAT®3-enhancer vector. The control construct, pAGUSTub3, contains only gusA and Tub3'. These constructs were electroporated into P. yezoensis protoplasts and the GUS activities were quantitatively analyzed by spectrometry. The results demonstrated that gusA gene was efficiently expressed in P. yezoensis protoplasts under the regulation of 5'-flanking sequence of the beta-tubulin gene. More interestingly, the pATubGUS produced stronger GUS activity in P. yezoensis protoplasts when compared to the result from pBI221, in which the gusA gene was directed by a constitutive CaMV 35S promoter. The data suggest that the integration of P. yezoensis protoplast and its endogenous beta-tubulin flanking sequences is a potential novel system for foreign gene expression.

  10. Uniformity of plants regenerated from orange (Citrus sinensis Osb.) protoplasts.

    PubMed

    Kobayashi, S

    1987-05-01

    Using 25 plants (protoclones) regenerated from orange (Citrus sinensis Osb.) protoplasts, several characters, including leaf and flower morphology, leaf oil, isozyme patterns and chromosome number, were examined. No significant variations in each character were recorded among the protoclones. Uniformity observed among protoclones was identical to that of nucellar seedlings.

  11. Genetic analysis of Bacillus stearothermophilus by protoplast fusion

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chen, Z.; Wojcik, S.F.; Welker, N.E.

    1986-03-01

    Efficient and reliable protoplasting, regeneration, and fusion techniques were established for the prototrophic strain Bacillus stearothermophilus NUB36. Auxotrophic mutants were isolated, and protoplast fusion was used to construct isogenic mutant strains and for chromosomal mapping. Markers were mapped using two-, three-, and four-factor crosses. The order of the markers was hom-1-thr-1-his-1-(gly-1 or gly-2)-pur-1-pur-2. These markers may be analogous to hom, thrA, hisA, glyC, and purA markers on the Bacillus subtilis chromosome. No analogous pur-1 marker has been reported in B. subtilis. The relative order of three of the markers (hom-1-thr-1-gly-1) was independently confirmed by transduction.

  12. Silencing GhNDR1 and GhMKK2 compromised cotton resistance to Verticillium wilt

    PubMed Central

    Gao, Xiquan; Wheeler, Terry; Li, Zhaohu; Kenerley, Charles M.; He, Ping; Shan, Libo

    2011-01-01

    SUMMARY Cotton is an important cash crop worldwide and serves as a significant source of fiber, feed, foodstuff, oil and biofuel products. Considerable effort in genetics and genomics has been expended to increase sustainable yield and quality through molecular breeding and genetic engineering of new cotton cultivars. With the effort of whole genome sequencing of cotton, it is essential to develop molecular tools and resources for large-scale analysis of gene functions at the genome-wide level. We have successfully established an Agrobacterium-mediated virus-induced gene silencing (VIGS) assay in several cotton cultivars with different genetic backgrounds. The genes of interest were potently and readily silenced within 2 weeks after inoculation at the seedling stage. Importantly, we showed that silencing GhNDR1 and GhMKK2 compromised cotton resistance to the infection by Verticillium dahliae, a fungal pathogen causing Verticillium wilt. Furthermore, we established a cotton protoplast system for transient gene expression to study gene functions by a gain-of-function approach. The viable protoplasts were isolated from green cotyledons, etiolated cotyledons, and true leaves, and responded to a wide range of pathogen elicitors and phytohormones. Remarkably, cotton plants possess conserved, but also distinct MAP kinase activation with Arabidopsis upon bacterial elicitor flagellin perception. Thus, we demonstrated that GhNDR1 and GhMKK2 are required for Verticillium resistance in cotton using gene silencing assays, and established the high throughput loss-of-function and gain-of-function assays for functional genomic studies in cotton. PMID:21219508

  13. Formation of Protoplasts from Resting Spores

    PubMed Central

    Fitz-James, Philip C.

    1971-01-01

    Coat-stripped spores suspended in hypertonic solutions and supplied with two essential cations can be converted into viable protoplasts by lysozyme digestion of both cortex and germ cell wall. Calcium ions are necessary to prevent membrane rupture, and magnesium ions are necessary for changes indicative of hydration of the core, particularily the nuclear mass. Since remnant spore coat covered such protoplasts of Bacillus subtilis and the germ cell wall of B. cereus spores is not lysozyme digestible, coatless spores of B. megaterium KM were more useful for these studies. Lysozyme digestion in cation-free environment produced a peculiar semi-refractile spore core free of a cortex but prone to rapid hydration and lytic changes on the addition of cations. Strontium could replace Ca2+ but Mn2+ could not replace Mg2+ in these digestions. When added to the spores, dipicolinic acid and other chelates appeared to compete with the membrane for the calcium needed for stabilization during lysozyme conversion to protoplasts. It is argued that calcium could function to stabilize the inner membrane anionic groups over the anhydrous dipicolinic acid-containing core of resting spores. Images PMID:4995380

  14. Polyamine metabolism and osmotic stress. II. Improvement of oat protoplasts by an inhibitor of arginine decarboxylase

    NASA Technical Reports Server (NTRS)

    Tiburcio, A. F.; Kaur-Sawhney, R.; Galston, A. W.

    1986-01-01

    We have attempted to improve the viability of cereal mesophyll protoplasts by pretreatment of leaves with DL-alpha-difluoromethylarginine (DFMA), a specific 'suicide' inhibitor of the enzyme (arginine decarboxylase) responsible for their osmotically induced putrescine accumulation. Leaf pretreatment with DFMA before a 6 hour osmotic shock caused a 45% decrease of putrescine and a 2-fold increase of spermine titer. After 136 hours of osmotic stress, putrescine titer in DFMA-pretreated leaves increased by only 50%, but spermidine and spermine titers increased dramatically by 3.2- and 6-fold, respectively. These increases in higher polyamines could account for the reduced chlorophyll loss and enhanced ability of pretreated leaves to incorporate tritiated thymidine, uridine, and leucine into macromolecules. Pretreatment with DFMA significantly improved the overall viability of the protoplasts isolated from these leaves. The results support the view that the osmotically induced rise in putrescine and blockage of its conversion to higher polyamines may contribute to the lack of sustained cell division in cereal mesophyll protoplasts, although other undefined factors must also play a major role.

  15. Regeneration and molecular characterization of an intergeneric hybrid between Graphium putredinis and Trichoderma harzianum by protoplasmic fusion.

    PubMed

    Savitha, S; Sadhasivam, S; Swaminathan, K

    2010-01-01

    The fungal strains Graphium putredinis and Trichoderma harzianum were selected as parents for fusant development. Protoplasts were isolated using the combination of lysing enzymes Novozym 234 and cellulase with 0.6M KCl as osmotic stabilizer. The optimum conditions for release of viable protoplasts from the fungal mycelium viz. age of the mycelium, lytic enzymes, osmotic stabilizers, pH, incubation period and regeneration medium were determined. Intergeneric protoplast fusion was carried out using 50% polyethylene glycol with calcium chloride (CaCl(2)) and glycine buffer and the conditions for effective protoplast fusion, viz. fusogen, osmotic stabilizer, pH, incubation period and regeneration medium were optimized. At optimum conditions, the regeneration frequency of the fused protoplasts on potato dextrose agar (PDA) medium and fusion frequency were calculated. The regeneration frequency on non-selective (PDA) and selective media (PDA amended with starch) was determined for the parental and fusant strains in which, fusant showed a higher rate of regeneration. Fusant formation was confirmed by morphological markers (colony morphology and spore size and shape) and genetical markers like, mycelial protein pattern, restriction digestion pattern and random amplified polymorphic DNA (RAPD) analysis. The efficiency of these parental strains and their intergeneric fusant in the production of hydrolytic enzymes - amylases (treatment plant for sago factory effluent), cellulases (bioethanol), xylanases (bleaching agents for waste paper pulp) and proteases (additives in commercial detergents) - have probable applications in various industrial processes. (c) 2010 Elsevier Inc. All rights reserved.

  16. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Berry, Elizabeth A.; Tran, Mai L.; Dimos, Christos S.

    In contrast to homeohydric vascular plants, mosses employ a poikilohydric strategy for surviving in the dry aerial environment. A detailed understanding of the structure, composition, and development of moss cell walls can contribute to our understanding of not only the evolution of overall cell wall complexity, but also the differences that have evolved in response to selection for different survival strategies. The model moss species Physcomitrella patens has a predominantly haploid lifecycle consisting of protonemal filaments that regenerate from protoplasts and enlarge by tip growth, and leafy gametophores composed of cells that enlarge by diffuse growth and differentiate into severalmore » different types. Advantages for genetic studies include methods for efficient targeted gene modification and extensive genomic resources. Immuno and affinity cytochemical labeling were used to examine the distribution of polysaccharides and proteins in regenerated protoplasts, protonemal filaments, rhizoids, and sectioned gametophores of P. patens. The cell wall composition of regenerated protoplasts was also characterized by flow cytometry. Crystalline cellulose was abundant in the cell walls of regenerating protoplasts and protonemal cells that developed on media of high osmolarity, whereas homogalactuonan was detected in the walls of protonemal cells that developed on low osmolarity media and not in regenerating protoplasts. Mannan was the major hemicellulose detected in all tissues tested. Arabinogalactan proteins were detected in different cell types by different probes, consistent with structural heterogneity. The results reveal developmental and cell type specific differences in cell wall composition and provide a basis for analyzing cell wall phenotypes in knockout mutants.« less

  17. Contributions of photosynthetic and non-photosynthetic cell types to leaf respiration in Vicia faba L. and their responses to growth temperature.

    PubMed

    Long, Benedict M; Bahar, Nur H A; Atkin, Owen K

    2015-11-01

    In intact leaves, mitochondrial populations are highly heterogeneous among contrasting cell types; how such contrasting populations respond to sustained changes in the environment remains, however, unclear. Here, we examined respiratory rates, mitochondrial protein composition and response to growth temperature in photosynthetic (mesophyll) and non-photosynthetic (epidermal) cells from fully expanded leaves of warm-developed (WD) and cold-developed (CD) broad bean (Vicia faba L.). Rates of respiration were significantly higher in mesophyll cell protoplasts (MCPs) than epidermal cell protoplasts (ECPs), with both protoplast types exhibiting capacity for cytochrome and alternative oxidase activity. Compared with ECPs, MCPs contained greater relative quantities of porin, suggesting higher mitochondrial surface area in mesophyll cells. Nevertheless, the relative quantities of respiratory proteins (normalized to porin) were similar in MCPs and ECPs, suggesting that ECPs have lower numbers of mitochondria yet similar protein complement to MCP mitochondria (albeit with lower abundance serine hydroxymethyltransferase). Several mitochondrial proteins (both non-photorespiratory and photorespiratory) exhibited an increased abundance in response to cold in both protoplast types. Based on estimates of individual protoplast respiration rates, combined with leaf cell abundance data, epidermal cells make a small but significant (2%) contribution to overall leaf respiration which increases twofold in the cold. Taken together, our data highlight the heterogeneous nature of mitochondrial populations in leaves, both among contrasting cell types and in how those populations respond to growth temperature. © 2015 John Wiley & Sons Ltd.

  18. Immuno and Affinity Cytochemical Analysis of Cell Wall Composition in the Moss Physcomitrella patens.

    PubMed

    Berry, Elizabeth A; Tran, Mai L; Dimos, Christos S; Budziszek, Michael J; Scavuzzo-Duggan, Tess R; Roberts, Alison W

    2016-01-01

    In contrast to homeohydric vascular plants, mosses employ a poikilohydric strategy for surviving in the dry aerial environment. A detailed understanding of the structure, composition, and development of moss cell walls can contribute to our understanding of not only the evolution of overall cell wall complexity, but also the differences that have evolved in response to selection for different survival strategies. The model moss species Physcomitrella patens has a predominantly haploid lifecycle consisting of protonemal filaments that regenerate from protoplasts and enlarge by tip growth, and leafy gametophores composed of cells that enlarge by diffuse growth and differentiate into several different types. Advantages for genetic studies include methods for efficient targeted gene modification and extensive genomic resources. Immuno and affinity cytochemical labeling were used to examine the distribution of polysaccharides and proteins in regenerated protoplasts, protonemal filaments, rhizoids, and sectioned gametophores of P. patens. The cell wall composition of regenerated protoplasts was also characterized by flow cytometry. Crystalline cellulose was abundant in the cell walls of regenerating protoplasts and protonemal cells that developed on media of high osmolarity, whereas homogalactuonan was detected in the walls of protonemal cells that developed on low osmolarity media and not in regenerating protoplasts. Mannan was the major hemicellulose detected in all tissues tested. Arabinogalactan proteins were detected in different cell types by different probes, consistent with structural heterogneity. The results reveal developmental and cell type specific differences in cell wall composition and provide a basis for analyzing cell wall phenotypes in knockout mutants.

  19. Basidiospore and Protoplast Regeneration from Raised Fruiting Bodies of Pathogenic Ganoderma boninense.

    PubMed

    Govender, Nisha T; Mahmood, Maziah; Seman, Idris A; Mui-Yun, Wong

    2016-08-26

    Ganoderma boninense, a phytopathogenic white rot fungus had sought minimal genetic characterizations despite huge biotechnological potentials. Thus, efficient collection of fruiting body, basidiospore and protoplast of G. boninense is described. Matured basidiocarp raised under the glasshouse conditions yielded a total of 8.3 × 104 basidiospores/ml using the low speed centrifugation technique. Mycelium aged 3-day-old treated under an incubation period of 3 h in lysing enzyme from Trichoderma harzianum (10 mg/ml) suspended in osmotic stabilizer (0.6 M potassium chloride and 20 mM dipotassium phosphate buffer) yielded the highest number of viable protoplasts (8.9 × 106 single colonies) among all possible combinations tested (regeneration media, age of mycelium, osmotic stabilizer, digestive enzyme and incubation period).

  20. Immuno and Affinity Cytochemical Analysis of Cell Wall Composition in the Moss Physcomitrella patens

    DOE PAGES

    Berry, Elizabeth A.; Tran, Mai L.; Dimos, Christos S.; ...

    2016-03-08

    In contrast to homeohydric vascular plants, mosses employ a poikilohydric strategy for surviving in the dry aerial environment. A detailed understanding of the structure, composition, and development of moss cell walls can contribute to our understanding of not only the evolution of overall cell wall complexity, but also the differences that have evolved in response to selection for different survival strategies. The model moss species Physcomitrella patens has a predominantly haploid lifecycle consisting of protonemal filaments that regenerate from protoplasts and enlarge by tip growth, and leafy gametophores composed of cells that enlarge by diffuse growth and differentiate into severalmore » different types. Advantages for genetic studies include methods for efficient targeted gene modification and extensive genomic resources. Immuno and affinity cytochemical labeling were used to examine the distribution of polysaccharides and proteins in regenerated protoplasts, protonemal filaments, rhizoids, and sectioned gametophores of P. patens. The cell wall composition of regenerated protoplasts was also characterized by flow cytometry. Crystalline cellulose was abundant in the cell walls of regenerating protoplasts and protonemal cells that developed on media of high osmolarity, whereas homogalactuonan was detected in the walls of protonemal cells that developed on low osmolarity media and not in regenerating protoplasts. Mannan was the major hemicellulose detected in all tissues tested. Arabinogalactan proteins were detected in different cell types by different probes, consistent with structural heterogneity. The results reveal developmental and cell type specific differences in cell wall composition and provide a basis for analyzing cell wall phenotypes in knockout mutants.« less

  1. Sodium Fluxes through Nonselective Cation Channels in the Plasma Membrane of Protoplasts from Arabidopsis Roots1

    PubMed Central

    Demidchik, Vadim; Tester, Mark

    2002-01-01

    The aim of the present work was to characterize Na+ currents through nonselective cation channels (NSCCs) in protoplasts derived from root cells of Arabidopsis. The procedure of the protoplast isolation was modified to increase the stability of Arabidopsis root protoplasts in low external Ca2+ by digesting tissue in elevated Ca2+. Experiments in whole-cell and outside-out modes were carried out. We found that Na+ currents in Arabidopsis root protoplasts were mediated by cation channels that were insensitive to externally applied tetraethylammonium+ and verapamil, had no time-dependent activation (permanently opened or completely activated within 1–2 ms), were voltage independent, and were weakly selective for monovalent cations. The selectivity sequence was as follows: K+ (1.49) > NH4+ (1.24) > Rb+ (1.15) ≈ Cs+ (1.10) ≈ Na+ (1.00) > Li+ (0.73) > tetraethylammonium+ (0.47). Arabidopsis root NSCCs were blocked by H+ (pK ≈ 6.0), Ca2+ (K1/2 ≈ 0.1 mm), Ba2+, Zn2+, La3+, Gd3+, quinine, and the His modifier diethylpyrocarbonate. They were insensitive to most organic blockers (nifedipine, verapamil, flufenamate, and amiloride) and to the SH-group modifier p-chloromercuriphenyl sulfonic acid. Voltage-insensitive, Ca2+-sensitive single channels were also resolved. Properties of Arabidopsis root NSCCs are discussed and compared with characteristics of similar conductances studied previously in plants and animals. It is suggested that NSCCs present a distinct group of plant ion channels, mediating toxic Na+ influx to the cell and probably having other important roles in physiological processes of plants. PMID:11842142

  2. Immuno and Affinity Cytochemical Analysis of Cell Wall Composition in the Moss Physcomitrella patens

    PubMed Central

    Berry, Elizabeth A.; Tran, Mai L.; Dimos, Christos S.; Budziszek, Michael J.; Scavuzzo-Duggan, Tess R.; Roberts, Alison W.

    2016-01-01

    In contrast to homeohydric vascular plants, mosses employ a poikilohydric strategy for surviving in the dry aerial environment. A detailed understanding of the structure, composition, and development of moss cell walls can contribute to our understanding of not only the evolution of overall cell wall complexity, but also the differences that have evolved in response to selection for different survival strategies. The model moss species Physcomitrella patens has a predominantly haploid lifecycle consisting of protonemal filaments that regenerate from protoplasts and enlarge by tip growth, and leafy gametophores composed of cells that enlarge by diffuse growth and differentiate into several different types. Advantages for genetic studies include methods for efficient targeted gene modification and extensive genomic resources. Immuno and affinity cytochemical labeling were used to examine the distribution of polysaccharides and proteins in regenerated protoplasts, protonemal filaments, rhizoids, and sectioned gametophores of P. patens. The cell wall composition of regenerated protoplasts was also characterized by flow cytometry. Crystalline cellulose was abundant in the cell walls of regenerating protoplasts and protonemal cells that developed on media of high osmolarity, whereas homogalactuonan was detected in the walls of protonemal cells that developed on low osmolarity media and not in regenerating protoplasts. Mannan was the major hemicellulose detected in all tissues tested. Arabinogalactan proteins were detected in different cell types by different probes, consistent with structural heterogneity. The results reveal developmental and cell type specific differences in cell wall composition and provide a basis for analyzing cell wall phenotypes in knockout mutants. PMID:27014284

  3. Green fluorescent protein expression from recombinant lettuce infectious yellows virus-defective RNAs originating from RNA 2.

    PubMed

    Yeh, H H; Tian, T; Medina, V; Falk, B W

    2001-10-10

    Lettuce infectious yellows virus (LIYV) RNA 2 defective RNAs (D RNAs) were compared in protoplasts for their ability to replicate and to express the green fluorescent protein (GFP) from recombinant D RNA constructs. Initially four LIYV D RNAs of different genetic composition were compared, but only two (LIYV D RNA M5 and M18) replicated to high levels. Both of these contained at least two complete ORFs, one being the 3'-terminal ORF encoding P26. Northern hybridization analysis using probes corresponding to 3' regions of LIYV RNA 2 detected the P26 subgenomic RNA from protoplasts infected with LIYV RNAs 1 and 2 or protoplasts inoculated only with RNA 1 plus either the LIYV D RNA M5 or M18, suggesting that these LIYV D RNAs served as templates to generate the P26 subgenomic RNA. The GFP coding region was inserted as an in-frame insertion into the P26 coding region of the LIYV M5 and M18 D RNAs, yielding M5gfp and M18gfp. When transcripts of M5gfp and M18gfp were used to inoculate protoplasts, bright fluorescence was seen only when they were co-inoculated with LIYV RNA 1. The percentage of fluorescent protoplasts ranged from experiment to experiment, but was as high as 5.8%. Time course analyses showed that fluorescence was not detected before 48 h pi, and this correlated with the timing of LIYV RNA 2 and RNA 2 D RNA accumulation, but not with that of LIYV RNA 1. Copyright 2001 Academic Press.

  4. Ca2+ transport in plant cells and mechanisms of transformation of phytochrome-induced photosignals

    NASA Astrophysics Data System (ADS)

    Volotovski, Igor D.

    1995-01-01

    The recent data on the influence of phytochrome on the efficiency of Ca2+ translocation across the membranes of oat protoplasts are given. Ca2+ uptake in the protoplasts was shown to be influenced by the red light (R) illumination. This effect was reverted by the following far-red light (FR) illumination. To elucidate the sensitivity to phytochrome-controlling action the screening between the mechanisms of Ca2+ transport across the plasma membranes of oat protoplasts, Na+/Ca2+ and Ca2+/H+ exchangers, Ca2+-pump and Ca2+-channel was done. It was established that phytochrome modulated the activity of Na+/Ca2+-exchanger and Ca2+-pump. The light-mediated oscillations of cytoplasmic Ca2+ concentration in the oat protoplasts were demonstrated using fluorescence probe quin2 loaded into the cells and laser monitoring of fluorescence signal. The evidences were obtained that the oscillations were not the result of the elevation of cytoplasmic Ca2+ concentration and had no connection with Ca2+ pool of mitochondria. The possibility of the relation between the Ca2+ oscillations and phosphoinositide metabolism in plant cell membranes is analyzed. The mechanisms of transformation of primary phytochrome signal into biological effects were discussed.

  5. Plant regeneration from cell suspension-derived protoplasts of Phalaenopsis.

    PubMed

    Shrestha, B R; Tokuhara, K; Mii, M

    2007-06-01

    Protoplasts isolated from cell suspension culture of Phalaenopsis "Wataboushi" were cultured by (a) embedding in gellan gum-solidified hormone-free 1/2 New Dogashima medium (1/2 NDM) containing 0.44 M sorbitol, 0.06 M sucrose and 0.1 g/l L-glutamine (standard method) and (b) beads method using beads of gellan gum or sodium alginate as the gelling agents which were surrounded by liquid NDM. Although, the two beads methods gave less frequency of initial protoplast division than the standard method, the former finally resulted in higher frequency of microcolony formation than the latter. The highest frequency of microcolony formation (23%) was obtained when protoplasts were embedded in 1% Ca-alginate beads and subcultured every two weeks by replacing the surrounding liquid culture medium with a decrease in sorbitol concentration by 0.1 M. Colonies visible to the naked eyes were observed within 2 months of culture and the regenerated calluses were transferred onto hormone-free NDM supplemented with 10 g/l maltose and 0.3% (w/v) gellan gum, on which PLBs were formed and proliferated profusely. The PLBs were regenerated into plantlets after changing the carbon source to 10 g/l sorbitol and successfully acclimatized to greenhouse conditions.

  6. Strain improvement of Sporolactobacillus inulinus ATCC 15538 for acid tolerance and production of D-lactic acid by genome shuffling.

    PubMed

    Zheng, Huijie; Gong, Jixian; Chen, Tao; Chen, Xun; Zhao, Xueming

    2010-02-01

    Improvement of acid tolerance and production of D-lactic acid by Sporolactobacillus inulinus ATCC 15538 was performed by using recursive protoplast fusion in a genome shuffling format. The starting population was generated by ultraviolet irradiation, diethyl sulfate mutagenesis, and pH-gradient filter and then, subjected for the recursive protoplast fusion. The concentration of lysozyme, time, and temperature for enzyme treatment were optimized by response surface methodology based on the central composite design. Based on contour plots and variance analysis, the model predicted a maximum Y (multiply protoplasts formation ratio by protoplasts regeneration ratio), 60.4%, and the corresponding above used values were 7.75 mg/ml lysozyme, 1.59 h, and 38 degrees C. A pH-5-resistant recombinant, F3-4, was obtained after three rounds of genome shuffling and its production of D-lactic acid reached 93.4 g/l in a 5 L bioreactor, which was increased by 39.8% and 119% in comparison with that of UV generated strain and the original strain S. inulinus ATCC 15538, respectively. The subculture experiments indicated that F3-4 was genetically stable.

  7. In Vitro Synthesized RNA Generated from cDNA Clones of Both Genomic Components of Cucurbit yellow stunting disorder virus Replicates in Cucumber Protoplasts

    PubMed Central

    Owen, Carolyn A.; Moukarzel, Romy; Huang, Xiao; Kassem, Mona A.; Eliasco, Eleonora; Aranda, Miguel A.; Coutts, Robert H. A.; Livieratos, Ioannis C.

    2016-01-01

    Cucurbit yellow stunting disorder virus (CYSDV), a bipartite whitefly-transmitted virus, constitutes a major threat to commercial cucurbit production worldwide. Here, construction of full-length CYSDV RNA1 and RNA2 cDNA clones allowed the in vitro synthesis of RNA transcripts able to replicate in cucumber protoplasts. CYSDV RNA1 proved competent for replication; transcription of both polarities of the genomic RNA was detectable 24 h post inoculation. Hybridization of total RNA extracted from transfected protoplasts or from naturally CYSDV-infected cucurbits revealed high-level transcription of the p22 subgenomic RNA species. Replication of CYSDV RNA2 following co-transfection with RNA1 was also observed, with similar transcription kinetics. A CYSDV RNA2 cDNA clone (T3CM8Δ) comprising the 5′- and 3′-UTRs plus the 3′-terminal gene, generated a 2.8 kb RNA able to replicate to high levels in protoplasts in the presence of CYSDV RNA1. The clone T3CM8Δ will facilitate reverse genetics studies of CYSDV gene function and RNA replication determinants. PMID:27314380

  8. Somatic hybrid plants from sexually incompatible woody species: Citrus reticulata and Citropsis gilletiana.

    PubMed

    Grosser, J W; Gmitter, F G; Tusa, N; Chandler, J L

    1990-04-01

    Allotetraploid intergeneric somatic hybrid plants between Citrus reticulata Blanco cv. Cleopatra mandarin and Citropsis gilletiana Swing. & M. Kell. (common name Gillet's cherry orange) were regenerated following protoplast fusion. Cleopatra protoplasts were isolated from an ovule-derived embryogenic suspension culture and fused chemically with leaf-derived protoplasts of Citropsis gilletiana. Cleopatra mandarin and somatic hybrid plants were regenerated via somatic embryogenesis. Hybrid plant identification was based on differential leaf morphology, root-tip cell chromosome number, and electrophoretic analyses of phosphoglucose mutase (PGM) and phosphohexose isomerase (PHI) isozyme banding patterns. This is the first somatic hybrid within the Rutaceae reported that does not have Citrus sinensis (sweet orange) as a parent, and the first produced with a commercially important citrus rootstock and a complementary but sexually incompatible, related species.

  9. Interspecific somatic hybridization between lettuce (Lactuca sativa) and wild species L. virosa.

    PubMed

    Matsumoto, E

    1991-02-01

    Somatic hybrids between cultivated lettuce (Lactuca sativa) and a wild species L. virosa were produced by protoplast electrofusion. Hybrid selection was based on inactivation of L. sativa with 20mM iodoacetamide for 15 min, and the inability of L. virosa protoplasts to divide in the culture conditions used. Protoplasts were cultured in agarose beads in a revised MS media. In all 71 calli were formed and 21 of them differentiated shoots on LS medium containing 0.1mg/l NAA and 0.2mg/l BA. Most regenerated plants exhibited intermediate morphology. These plants were confirmed as hybrids by isoenzyme analysis. The majority of somatic hybrids had 2n=4x=36 chromosomes, and had more vigorous growth than either parent. Hybrids had normal flower morphology, but all were sterile.

  10. Hybridization and breeding of the benomyl resistant mutant, Trichoderma harziantum antagonized to phytopathogenic fungi by protoplast fusion.

    PubMed

    Ogawa, K; Yoshida, N; Gesnara, W; Omumasaba, C A; Chamuswarng, C

    2000-04-01

    A diploid strain obtained from heterokaryons of Trichoderma harzianum by protoplast fusion grew on minimal medium containing 100ppm benomyl. This strain inhibited the growth of the phytopathogenic fungus Fusarium oxysporum f. sp. raphani on paired cultures and also protected against radish yellows and a drop in germination induced by F. oxysporum f. sp. raphani.

  11. Large-scale gene expression profiling data for the model moss Physcomitrella patens aid understanding of developmental progression, culture and stress conditions.

    PubMed

    Hiss, Manuel; Laule, Oliver; Meskauskiene, Rasa M; Arif, Muhammad A; Decker, Eva L; Erxleben, Anika; Frank, Wolfgang; Hanke, Sebastian T; Lang, Daniel; Martin, Anja; Neu, Christina; Reski, Ralf; Richardt, Sandra; Schallenberg-Rüdinger, Mareike; Szövényi, Peter; Tiko, Theodhor; Wiedemann, Gertrud; Wolf, Luise; Zimmermann, Philip; Rensing, Stefan A

    2014-08-01

    The moss Physcomitrella patens is an important model organism for studying plant evolution, development, physiology and biotechnology. Here we have generated microarray gene expression data covering the principal developmental stages, culture forms and some environmental/stress conditions. Example analyses of developmental stages and growth conditions as well as abiotic stress treatments demonstrate that (i) growth stage is dominant over culture conditions, (ii) liquid culture is not stressful for the plant, (iii) low pH might aid protoplastation by reduced expression of cell wall structure genes, (iv) largely the same gene pool mediates response to dehydration and rehydration, and (v) AP2/EREBP transcription factors play important roles in stress response reactions. With regard to the AP2 gene family, phylogenetic analysis and comparison with Arabidopsis thaliana shows commonalities as well as uniquely expressed family members under drought, light perturbations and protoplastation. Gene expression profiles for P. patens are available for the scientific community via the easy-to-use tool at https://www.genevestigator.com. By providing large-scale expression profiles, the usability of this model organism is further enhanced, for example by enabling selection of control genes for quantitative real-time PCR. Now, gene expression levels across a broad range of conditions can be accessed online for P. patens. © 2014 The Authors The Plant Journal © 2014 John Wiley & Sons Ltd.

  12. Nonselective Currents and Channels in Plasma Membranes of Protoplasts from Coats of Developing Seeds of Bean1

    PubMed Central

    Zhang, Wen-Hao; Skerrett, Martha; Walker, N. Alan; Patrick, John W.; Tyerman, Stephen D.

    2002-01-01

    In developing bean (Phaseolus vulgaris) seeds, phloem-imported nutrients move in the symplast from sieve elements to the ground parenchyma cells where they are transported across the plasma membrane into the seed apoplast. To study the mechanisms underlying this transport, channel currents in ground parenchyma protoplasts were characterized using patch clamp. A fast-activating outward current was found in all protoplasts, whereas a slowly activating outward current was observed in approximately 25% of protoplasts. The two currents had low selectivity for univalent cations, but the slow current was more selective for K+ over Cl− (PK:PCl = 3.6–4.2) than the fast current (PK:PCl = 1.8–2.5) and also displayed Ca2+ selectivity. The slow current was blocked by Ba2+, whereas both currents were blocked by Gd3+ and La3+. Efflux of K+ from seed coat halves was inhibited 25% by Gd3+ and La3+ but was stimulated by Ba2+ and Cs+, suggesting that only the fast current may be a component in the pathway for K+ release. An “instantaneous” inward current observed in all protoplasts exhibited similar pharmacology and permeability for univalent cations to the fast outward current. In outside-out patches, two classes of depolarization-activated cation-selective channels were observed: one slowly activating of low conductance (determined from nonstationary noise to be 2.4 pS) and another with conductances 10-fold higher. Both channels occurred at high density. The higher conductance channel in 10 mm KCl had PK:PCl = 2.8. Such nonselective channels in the seed coat ground parenchyma cell could function to allow some of the efflux of phloem-imported univalent ions into the seed apoplast. PMID:11842143

  13. Influence of protoplast fusion between two Trichoderma spp. on extracellular enzymes production and antagonistic activity.

    PubMed

    Hassan, Mohamed M

    2014-11-02

    Biological control plays a crucial role in grapevine pathogens disease management. The cell-wall degrading enzymes chitinase, cellulase and β-glucanase have been suggested to be essential for the mycoparasitism activity of Trichoderma species against grapevine fungal pathogens. In order to develop a useful strain as a single source of these vital enzymes, it was intended to incorporate the characteristics of two parental fungicides tolerant mutants of Trichoderma belonging to the high chitinase producing species T. harzianum and the high cellulase producing species T. viride , by fusing their protoplasts. The phylogeny of the parental strains was carried out using a sequence of the 5.8S-ITS region. The BLAST of the obtained sequence identified these isolates as T. harzianum and T. viride . Protoplasts were isolated using lysing enzymes and were fused using polyethylene glycol. The fused protoplasts have been regenerated on protoplast regeneration minimal medium supplemented with two selective fungicides. Among the 40 fast growing fusants, 17 fusants were selected based on their enhanced growth on selective media for further studies. The fusant strains were growing 60%-70% faster than the parents up to third generation. All the 17 selected fusants exhibited morphological variations. Some fusant strains displayed threefold increased chitinase enzyme activity and twofold increase in β-glucanase enzyme activity compared to the parent strains. Most fusants showed powerful antagonistic activity against Macrophomin aphaseolina , Pythium ultimum and Sclerotium rolfsii pathogens. Fusant number 15 showed the highest inhibition percentage (92.8%) against M. phaseolina and P. ultimum, while fusant number 9 showed the highest inhibition percentage (98.2%) against the growth of S. rolfsii. A hyphal intertwining and degradation phenomenon was observed by scanning electron microscope. The Trichoderma antagonistic effect against pathogenic fungal mycelia was due to the mycoparasitism effect of the extracellular enzymes.

  14. Molecular Sieving by the Bacillus megaterium Cell Wall and Protoplast

    PubMed Central

    Scherrer, Rene; Gerhardt, Philipp

    1971-01-01

    Passive permeabilities of the cell wall and protoplast of Bacillus megaterium strain KM were characterized by use of 50 hydrophilic probing molecules (tritiated water, sugars, dextrans, glycols, and polyglycols) which varied widely in size. Weight per cent uptake values (Rw) were measured at diffusional equilibrium under conditions that negated the influences of adsorption or active transport. Plots of Rw for intact cells as a function of number-average molecular weight (¯Mn) or Einstein-Stokes hydrodynamic radius (¯rES) of the solutes showed three phases: a protoplast uptake phase with a polydisperse exclusion threshold of ¯Mn = 0.6 × 103 to 1.1 × 103, ¯rES = 0.6 to 1.1 nm; a cell wall uptake phase with a polydisperse exclusion threshold of ¯Mn = 0.7 × 105 to 1.2 × 105, ¯rES ≅ 8.3 nm; and a total exclusion phase. Isolated cell walls showed only the latter two phases. However, it became evident that the cell wall selectively passed only the smallest molecules in a heterodisperse polymer sample. When the molecular-weight distributions of polyglycol samples (¯Mn = 1,000, 1,450, and 3,350) were determined by analytical gel chromatography before and after uptake by intact cells or isolated cell walls, a quasi-monodisperse exclusion threshold was obtained corresponding to Mn = 1,200, rES = 1.1 nm. The permeability of isolated protoplasts was assessed by the relative ability of solutes to effect osmotic stabilization. An indefinite exclusion threshold, evident even with monodisperse sugars, was attributed to lengthwise orientation of the penetrating rod-shaped molecules. Altogether, the best estimate of the limiting equivalent porosity of the protoplast was 0.4 to 0.6 nm in radius and of the cell wall, 1.1 nm. PMID:4999413

  15. La3+ uptake and its effect on the cytoskeleton in root protoplasts of Zea mays L.

    PubMed

    Liu, Min; Hasenstein, Karl H

    2005-03-01

    La(3+) ions are known to antagonize Ca(2+) and are used as a Ca(2+) channel blocker but little is known on the direct effects of La(3+). Micromolar La(3+) concentrations promoted root growth while higher concentrations were inhibitory. The uptake of La(3+) in maize root protoplasts revealed a membrane binding component (0.14 and 0.44 pmol min(-1) protoplast(-1) for 100 and 1,000 microM La(3+)) followed by a slower concentration and time-dependent uptake. Uptake was reduced by Ca(2+), but had no substantial effect on other ions. La(3+) shifted microtubule organization from random to parallel but caused aggregation of microfilaments. Our data suggest that La(3+) is taken up into plant cells and affects growth via stabilization of the cytoskeleton.

  16. Intraspecific protoplast fusion of Brettanomyces anomalus for improved production of an extracellular β-glucosidase.

    PubMed

    Wu, Peng; Zhao, Xihong; Pan, Siyi

    2014-09-03

    Improvement of production of an extracellular β-glucosidase with high activity by Brettanomyces anomalus PSY-001 was performed by using recursive protoplast fusion in a genome-shuffling format. The initial population was generated by ultraviolet irradiation, ultrasonic mutagenesis and, then, subjected to recursive protoplast fusion. Mutant strains exhibiting significantly higher β-glucosidase activities in liquid media were isolated. The best mutant strain showed increased cell growth in a flask culture, as well as increased β-glucosidase production. A recombinant strain, F3-25, was obtained after three rounds of genome shuffling and its production of β-glucosidase activity reached 4790 U L -1 , which was a nearly eightfold increase compared to the original strain B. anomalus PSY-001. The subculture experiments indicated that F3-25 was genetically stable.

  17. Intraspecific protoplast fusion of Brettanomyces anomalus for improved production of an extracellular β-glucosidase

    PubMed Central

    Wu, Peng; Zhao, Xihong; Pan, Siyi

    2014-01-01

    Improvement of production of an extracellular β-glucosidase with high activity by Brettanomyces anomalus PSY-001 was performed by using recursive protoplast fusion in a genome-shuffling format. The initial population was generated by ultraviolet irradiation, ultrasonic mutagenesis and, then, subjected to recursive protoplast fusion. Mutant strains exhibiting significantly higher β-glucosidase activities in liquid media were isolated. The best mutant strain showed increased cell growth in a flask culture, as well as increased β-glucosidase production. A recombinant strain, F3-25, was obtained after three rounds of genome shuffling and its production of β-glucosidase activity reached 4790 U L−1, which was a nearly eightfold increase compared to the original strain B. anomalus PSY-001. The subculture experiments indicated that F3-25 was genetically stable. PMID:26019572

  18. Arabidopsis Regenerating Protoplast: A Powerful Model System for Combining the Proteomics of Cell Wall Proteins and the Visualization of Cell Wall Dynamics

    PubMed Central

    Yokoyama, Ryusuke; Kuki, Hiroaki; Kuroha, Takeshi; Nishitani, Kazuhiko

    2016-01-01

    The development of a range of sub-proteomic approaches to the plant cell wall has identified many of the cell wall proteins. However, it remains difficult to elucidate the precise biological role of each protein and the cell wall dynamics driven by their actions. The plant protoplast provides an excellent means not only for characterizing cell wall proteins, but also for visualizing the dynamics of cell wall regeneration, during which cell wall proteins are secreted. It therefore offers a unique opportunity to investigate the de novo construction process of the cell wall. This review deals with sub-proteomic approaches to the plant cell wall through the use of protoplasts, a methodology that will provide the basis for further exploration of cell wall proteins and cell wall dynamics. PMID:28248244

  19. Actin dynamics mediates the changes of calcium level during the pulvinus movement of Mimosa pudica

    PubMed Central

    Yao, Heng; Xu, Qiangyi

    2008-01-01

    The bending movement of the pulvinus of Mimosa pudica is caused by a rapid change in volume of the abaxial motor cells, in response to various environmental stimuli. We investigated the relationship between the actin cytoskeleton and changes in the level of calcium during rapid contractile movement of the motor cells that was induced by electrical stimulation. The bending of the pulvinus was retarded by treatments with actin-affecting reagents and calcium channel inhibitors. The actin filaments in the motor cells were fragmented in response to electrical stimulation. Further investigations were performed using protoplasts from the motor cells of M. pudica pulvini. Calcium-channel inhibitors and EGTA had an inhibitory effect on contractile movement of the protoplasts. The level of calcium increased and became concentrated in the tannin vacuole after electrical stimulation. Ruthenium Red inhibited the increase in the level of calcium in the tannin vacuole and the contractile movement of the protoplasts. However, treatment with latrunculin A abolished the inhibitory effect of Ruthenium Red. Phalloidin inhibited the contractile movement and the increase in the level of calcium in the protoplasts. Our study demonstrates that depolymerization of the actin cytoskeleton in pulvinus motor cells in response to electrical signals results in increased levels of calcium. PMID:19513198

  20. Cloning and expression of an alpha-1,3-glucanase gene from Bacillus circulans KA-304: the enzyme participates in protoplast formation of Schizophyllum commune.

    PubMed

    Yano, Shigekazu; Wakayama, Mamoru; Tachiki, Takashi

    2006-07-01

    A culture filtrate of Bacillus circulans KA-304 grown on a cell-wall preparation of Schizophyllum commune has an activity to form protoplasts from S. commune mycelia, and a combination of alpha-1,3-glucanase and chitinase I, which were isolated from the filtrate, brings about the protoplast-forming activity. The gene of alpha-1,3-glucanase was cloned from B. circulans KA-304. It consists of 3,879 nucleotides, which encodes 1,293 amino acids including a putative signal peptide (31 amino acid residues), and the molecular weight of alpha-1,3-glucanase without the putative signal peptide was calculated to be 132,184. The deduced amino acid sequence of alpha-1,3-glucanase of B. circulans KA-304 showed approximately 80% similarity to that of mutanase (alpha-1,3-glucanase) of Bacillus sp. RM1, but no significant similarity to those of fungal mutanases. The recombinant alpha-1,3-glucanase was expressed in Escherichia coli Rosetta-gami B (DE 3), and significant alpha-1,3-glucanase activity was detected in the cell-free extract of the organism treated with isopropyl-beta-D-thiogalactopyranoside. The recombinant alpha-1,3-glucanase showed protoplast-forming activity when the enzyme was combined with chitinase I.

  1. Mixing of maize and wheat genomic DNA by somatic hybridization in regenerated sterile maize plants.

    PubMed

    Szarka, B.; Göntér, I.; Molnár-Láng, M.; Mórocz, S.; Dudits, D.

    2002-07-01

    Intergeneric somatic hybridization was performed between albino maize ( Zea mays L.) protoplasts and mesophyll protoplasts of wheat ( Triticum aestivum L.) by polyethylene glycol (PEG) treatments. None of the parental protoplasts were able to produce green plants without fusion. The maize cells regenerated only rudimentary albino plantlets of limited viability, and the wheat mesophyll protoplasts were unable to divide. PEG-mediated fusion treatments resulted in hybrid cells with mixed cytoplasm. Six months after fusion green embryogenic calli were selected as putative hybrids. The first-regenerates were discovered as aborted embryos. Regeneration of intact, green, maize-like plants needed 6 months of further subcultures on hormone-free medium. These plants were sterile, although had both male and female flowers. The cytological analysis of cells from callus tissues and root tips revealed 56 chromosomes, but intact wheat chromosomes were not observed. Using total DNA from hybrid plants, three RAPD primer combinations produced bands resembling the wheat profile. Genomic in situ hybridization (GISH) using total wheat DNA as a probe revealed the presence of wheat DNA islands in the maize chromosomal background. The increased viability and the restored green color were the most-significant new traits as compared to the original maize parent. Other intermediate morphological traits of plants with hybrid origin were not found.

  2. IP/sub 3/ stimulates CA/sup + +/ efflux from fusogenic carrot protoplasts

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rincon, M.; Boss, W.F.

    1986-04-01

    Polyphosphoinositide breakdown plays an important role in signal transduction in animal cells (Berridge and Irvine, 1984, Nature, 312:315). Upon stimulation, phospholipase C hydrolyzes phosphatidylinositol 4,5-bisphosphate to inositol 1,4,5-trisphosphate (IP/sub 3/) and diacylglycerol both of which act as cellular second messengers. IP/sub 3/ mobilizes Ca/sup + +/ from internal stores, hence the cytosolic free Ca/sup + +/ concentration increases and those physiological activities regulated by Ca/sup + +/ are stimulated. To test if plant cells also responded to IP/sub 3/, Ca/sup + +/ efflux studies were done with fusogenic carrot protoplasts released in EGTA. The protoplasts were preloaded with /sup 45/Ca/supmore » + +/ placed in a Ca/sup + +/-free medium, and efflux determined as /sup 45/Ca/sup + +/ loss from the protoplasts. IP/sub 3/ (10-20..mu..M) caused enhanced /sup 45/Ca/sup + +/ efflux and the response was sustained for at least 15 min. In plants, as in animals, the observed IP/sub 3/-enhanced /sup 45/Ca/sup + +/ efflux suggested that IP/sub 3/ released Ca/sup + +/ from internal stores, and the increased free cytosolic Ca/sup + +/ activated Ca/sup + +/ pumping mechanisms which restored the Ca/sup + +/ concentration in the cytosol to the normal level.« less

  3. The Utilization of Plant Facilities on the International Space Station—The Composition, Growth, and Development of Plant Cell Walls under Microgravity Conditions

    PubMed Central

    Jost, Ann-Iren Kittang; Hoson, Takayuki; Iversen, Tor-Henning

    2015-01-01

    In the preparation for missions to Mars, basic knowledge of the mechanisms of growth and development of living plants under microgravity (micro-g) conditions is essential. Focus has centered on the g-effects on rigidity, including mechanisms of signal perception, transduction, and response in gravity resistance. These components of gravity resistance are linked to the evolution and acquisition of responses to various mechanical stresses. An overview is given both on the basic effect of hypergravity as well as of micro-g conditions in the cell wall changes. The review includes plant experiments in the US Space Shuttle and the effect of short space stays (8–14 days) on single cells (plant protoplasts). Regeneration of protoplasts is dependent on cortical microtubules to orient the nascent cellulose microfibrils in the cell wall. The space protoplast experiments demonstrated that the regeneration capacity of protoplasts was retarded. Two critical factors are the basis for longer space experiments: a. the effects of gravity on the molecular mechanisms for cell wall development, b. the availability of facilities and hardware for performing cell wall experiments in space and return of RNA/DNA back to the Earth. Linked to these aspects is a description of existing hardware functioning on the International Space Station. PMID:27135317

  4. Optical trapping inside living organisms

    NASA Astrophysics Data System (ADS)

    Hansen, Poul M.; Oddershede, Lene B.

    2005-08-01

    We use optical tweezers to investigate processes happening inside ving cells. In a previous study, we trapped naturally occurring lipid granules inside living yeast cells, and used them to probe the viscoelastic properties of the cytoplasm. However, we prefer to use probes which can be specifically attached to various organelles within the living cells in order to optically quantify the forces acting on these organelles. Therefore, we have chosen to use nanometer sized gold beads as probes. These gold beads can be conjugated and attached chemically to the organelles of interest. Only Rayleigh metallic particles can be optically trapped and for these it is the case that the larger the beads, the larger the forces which can be exerted and thus measured using optical tweezers. The gold nanoparticles are injected into the cytoplasm using micropipettes. The very rigid cell wall of the S. pombe yeast cells poses a serious obstacle to this injection. In order to be able to punch a hole in the cell, first, the cells have to be turned into protoplasts, where only a lipid bilayer separates the cytoplasm from the surrounding media. We show how to perform micropipette delivery into the protoplasts and also how the protoplasts can be ablated using the trapping laserlight. Finally, we demonstrate that we can transform the protoplasts back to normal yeast cells.

  5. The Utilization of Plant Facilities on the International Space Station-The Composition, Growth, and Development of Plant Cell Walls under Microgravity Conditions.

    PubMed

    Jost, Ann-Iren Kittang; Hoson, Takayuki; Iversen, Tor-Henning

    2015-01-20

    In the preparation for missions to Mars, basic knowledge of the mechanisms of growth and development of living plants under microgravity (micro-g) conditions is essential. Focus has centered on the g-effects on rigidity, including mechanisms of signal perception, transduction, and response in gravity resistance. These components of gravity resistance are linked to the evolution and acquisition of responses to various mechanical stresses. An overview is given both on the basic effect of hypergravity as well as of micro-g conditions in the cell wall changes. The review includes plant experiments in the US Space Shuttle and the effect of short space stays (8-14 days) on single cells (plant protoplasts). Regeneration of protoplasts is dependent on cortical microtubules to orient the nascent cellulose microfibrils in the cell wall. The space protoplast experiments demonstrated that the regeneration capacity of protoplasts was retarded. Two critical factors are the basis for longer space experiments: a. the effects of gravity on the molecular mechanisms for cell wall development, b. the availability of facilities and hardware for performing cell wall experiments in space and return of RNA/DNA back to the Earth. Linked to these aspects is a description of existing hardware functioning on the International Space Station.

  6. Naturally induced secretions of the potato cyst nematode co-stimulate the proliferation of both tobacco leaf protoplasts and human peripheral blood mononuclear cells.

    PubMed

    Goverse, A; Rouppe van der Voort, J; Roppe van der Voort, C; Kavelaars, A; Smant, G; Schots, A; Bakker, J; Helder, J

    1999-10-01

    Naturally induced secretions from infective juveniles of the potato cyst nematode Globodera rostochiensis co-stimulate the proliferation of tobacco leaf protoplasts in the presence of the synthetic phytohormones alpha-naphthaleneacetic acid (NAA) and 6-benzylaminopurine (BAP). With the use of a protoplast-based bioassay, a low-molecular-weight peptide(s) (< 3 kDa) was shown to be responsible for the observed effect. This mitogenic oligopeptide(s) is functionally dissimilar to auxin and cytokinin and, in addition, it does not change the sensitivity of the protoplasts toward these phytohormones. In combination with the mitogen phytohemagglutinin (PHA), cyst nematode secretions also co-stimulated mitogenesis in human peripheral blood mononuclear cells (PBMC). The stimulation of plant cells isolated from nontarget tissue--these nematodes normally invade the roots of potato plants--suggests the activation of a general signal transduction mechanism(s) by an oligopeptide(s) secreted by the nematode. Whether a similar oligopeptide-induced mechanism underlies human PBMC activation remains to be investigated. Reactivation of the cell cycle is a crucial event in feeding cell formation by cyst nematodes. The secretion of a mitogenic low-molecular-weight peptide(s) by infective juveniles of the potato cyst nematode could contribute to the redifferentiation of plant cells into such a feeding cell.

  7. Nondestructive Biophysical Probes of the Basis and Mechanism of Resistance in Microbial Spores.

    DTIC Science & Technology

    1983-05-10

    correlated with their water content, wet density, and protoplast/sporoplast volume ratio; (2) photometric immersion refractometry was used to show that the...immersion refractometry was used to determine if dehydration of the protoplast accounts for sporal resistance to heat. These and other approaches...in above). c. Gerhardt, P., T.C. Beaman, T.R. Corner, J.T. Greenamayer and L.S. Tisa. 1981. Photometric immersion Refractometry of Bacterial Spores

  8. Droplet-based microfluidic analysis and screening of single plant cells.

    PubMed

    Yu, Ziyi; Boehm, Christian R; Hibberd, Julian M; Abell, Chris; Haseloff, Jim; Burgess, Steven J; Reyna-Llorens, Ivan

    2018-01-01

    Droplet-based microfluidics has been used to facilitate high-throughput analysis of individual prokaryote and mammalian cells. However, there is a scarcity of similar workflows applicable to rapid phenotyping of plant systems where phenotyping analyses typically are time-consuming and low-throughput. We report on-chip encapsulation and analysis of protoplasts isolated from the emergent plant model Marchantia polymorpha at processing rates of >100,000 cells per hour. We use our microfluidic system to quantify the stochastic properties of a heat-inducible promoter across a population of transgenic protoplasts to demonstrate its potential for assessing gene expression activity in response to environmental conditions. We further demonstrate on-chip sorting of droplets containing YFP-expressing protoplasts from wild type cells using dielectrophoresis force. This work opens the door to droplet-based microfluidic analysis of plant cells for applications ranging from high-throughput characterisation of DNA parts to single-cell genomics to selection of rare plant phenotypes.

  9. Enhanced production of fructosyltransferase in Aspergillus oryzae by genome shuffling.

    PubMed

    Wang, Shenghai; Duan, Mengjie; Liu, Yalan; Fan, Sen; Lin, Xiaoshan; Zhang, Yi

    2017-03-01

    To breed Aspergillus oryzae strains with high fructosyltransferase (FTase) activity using intraspecific protoplast fusion via genome-shuffling. A candidate library was developed using UV/LiCl of the conidia of A. oryzae SBB201. By screening for enzyme activity and cell biomass, two mutants (UV-11 and UV-76) were chosen for protoplast fusion and subsequent genome shuffling. After three rounds of genome recombination, a fusion mutant RIII-7 was obtained. Its FTase activity was 180 U g -1 , approximately double that of the original strain, and RIII-7 was genetically stable. In fermentation culture, FTase activity of the genome-shuffled strain reached a maximum of 353 U g -1 using substrate-feeding method, and this value was approximately 3.4-times higher than that of the original strain A. oryzae SBB201. Intraspecific protoplast fusion of A. oryzae significantly enhanced FTase activity and generated a potentially useful strain for industrial production.

  10. Immunological properties of Micrococcus lysodeikticus membranes.

    PubMed

    Fukui, Y; Nachbar, M S; Salton, M R

    1971-01-01

    Membranes of Micrococcus lysodeikticus possess antigens which are distinct from other cellular components such as cytoplasm, ribosomes, and cell walls. Only a few (two to three) components are found when dissociated membranes are examined by immunodiffusion and immunoelectrophoresis techniques. Membranes treated with 0.3% sodium dodecyl sulfate, 0.3% Triton X-100, trypsin, phospholipase A or C, or by sonic oscillation at pH 9.0, all showed the same pattern (three major bands) when examined against membrane antisera by immunoelectrophoresis. Immunological analysis of fractions isolated by sucrose gradient centrifugation or by polyacrylamide gel electrophoresis suggests that individual components cross-react. Antibodies to adenosine triphosphatase (EC 3.6.1.3) and fast-moving component are not removed by absorption with protoplasts. Removal of antibody to one of the membrane antigens by protoplast absorption indicated a surface location. Glutaraldehyde fixation of protoplasts resulted in the loss of membrane antigens detectable by immunodiffusion.

  11. JPRS Report, Science & Technology China

    DTIC Science & Technology

    1989-02-23

    Protoplast Culture of Rice (Oryza sativa L.), Plant Regeneration From Protoplast-Derived Calli 40091011a Beijing YICHUAN XUEBAO [ACTA GENETICA ...YICHUAN XUEBAO [ACTA GENETICA SINICA] in Chinese Vol 15 No 5, Oct 88 pp 329-334 [English abstract of article by Tao Zirong [7118 5261 2837], et al...Chang, et al., ACTA GENETICA SINICA, Vol 7 No 3, 1980 pp 283-288. 7. Zhu Zhongchun, et al., ACTA GENETICA SINICA, Vol 8 No 1, 1981 pp 63-65, 8. Mix, G

  12. Chlorophyllase is a rate-limiting enzyme in chlorophyll catabolism and is posttranslationally regulated.

    PubMed

    Harpaz-Saad, Smadar; Azoulay, Tamar; Arazi, Tzahi; Ben-Yaakov, Eran; Mett, Anahit; Shiboleth, Yoel M; Hörtensteiner, Stefan; Gidoni, David; Gal-On, Amit; Goldschmidt, Eliezer E; Eyal, Yoram

    2007-03-01

    Chlorophyll is a central player in harvesting light energy for photosynthesis, yet the rate-limiting steps of chlorophyll catabolism and the regulation of the catabolic enzymes remain unresolved. To study the role and regulation of chlorophyllase (Chlase), the first enzyme of the chlorophyll catabolic pathway, we expressed precursor and mature versions of citrus (Citrus sinensis) Chlase in two heterologous plant systems: (1) squash (Cucurbita pepo) plants using a viral vector expression system; and (2) transiently transformed tobacco (Nicotiana tabacum) protoplasts. Expression of full-length citrus Chlase resulted in limited chlorophyll breakdown in protoplasts and no visible leaf phenotype in whole plants, whereas expression of a Chlase version lacking the N-terminal 21 amino acids (ChlaseDeltaN), which corresponds to the mature protein, led to extensive chlorophyll breakdown in both tobacco protoplasts and squash leaves. ChlaseDeltaN-expressing squash leaves displayed a dramatic chlorotic phenotype in plants grown under low-intensity light, whereas under natural light a lesion-mimic phenotype occurred, which was demonstrated to follow the accumulation of chlorophyllide, a photodynamic chlorophyll breakdown product. Full-length and mature citrus Chlase versions were localized to the chloroplast membrane fraction in expressing tobacco protoplasts, where processing of the N-terminal 21 amino acids appears to occur. Results obtained in both plant systems suggest that Chlase functions as a rate-limiting enzyme in chlorophyll catabolism controlled via posttranslational regulation.

  13. DNA-Free Genetically Edited Grapevine and Apple Protoplast Using CRISPR/Cas9 Ribonucleoproteins.

    PubMed

    Malnoy, Mickael; Viola, Roberto; Jung, Min-Hee; Koo, Ok-Jae; Kim, Seokjoong; Kim, Jin-Soo; Velasco, Riccardo; Nagamangala Kanchiswamy, Chidananda

    2016-01-01

    The combined availability of whole genome sequences and genome editing tools is set to revolutionize the field of fruit biotechnology by enabling the introduction of targeted genetic changes with unprecedented control and accuracy, both to explore emergent phenotypes and to introduce new functionalities. Although plasmid-mediated delivery of genome editing components to plant cells is very efficient, it also presents some drawbacks, such as possible random integration of plasmid sequences in the host genome. Additionally, it may well be intercepted by current process-based GMO regulations, complicating the path to commercialization of improved varieties. Here, we explore direct delivery of purified CRISPR/Cas9 ribonucleoproteins (RNPs) to the protoplast of grape cultivar Chardonnay and apple cultivar such as Golden delicious fruit crop plants for efficient targeted mutagenesis. We targeted MLO-7 , a susceptible gene in order to increase resistance to powdery mildew in grape cultivar and DIPM-1, DIPM-2 , and DIPM-4 in the apple to increase resistance to fire blight disease. Furthermore, efficient protoplast transformation, the molar ratio of Cas9 and sgRNAs were optimized for each grape and apple cultivar. The targeted mutagenesis insertion and deletion rate was analyzed using targeted deep sequencing. Our results demonstrate that direct delivery of CRISPR/Cas9 RNPs to the protoplast system enables targeted gene editing and paves the way to the generation of DNA-free genome edited grapevine and apple plants.

  14. Regeneration of asymmetric somatic hybrid plants from the fusion of two types of wheat with Russian wildrye.

    PubMed

    Li, Cuiling; Xia, Guangmin; Xiang, Fengning; Zhou, Chuanen; Cheng, Aixia

    2004-12-01

    Two types of protoplasts of wheat (Triticum aestivum L. cv. Jinan 177) were used in fusion experiments--cha9, with a high division frequency, and 176, with a high regeneration frequency. The fusion combination of either cha9 or 176 protoplasts with Russian wildrye protoplasts failed to produce regenerated calli. When a mixture of cha9 and 176 protoplasts were fused with those of Russian wildrye, 14 fusion-derived calli were produced, of which seven differentiated into green plants and two differentiated into albinos. The morphology of all hybrid plants strongly resembled that of the parental wheat type. The hybrid nature of the cell lines was confirmed by cytological, isozyme, random amplified polymorphic DNA (RAPD) and genomic in situ hybridization (GISH) analyses. GISH analysis revealed that only chromosome fragments of Russian wildrye were transferred to the wheat chromosomes of hybrid calli and plants. Simple sequence repeat (SSR) analysis of the chloroplast genome of the hybrids with seven pairs of wheat-specific chloroplast microsatellite primers indicated that all of the cell lines had band patterns identical to wheat. Our results show that highly asymmetric somatic hybrid calli and plants can be produced via symmetric fusion in a triparental fusion system. The dominant effect of two wheat cell lines on the exclusion of Russian wildrye chromosomes is discussed.

  15. Effect of microgravity environment on cell wall regeneration, cell divisions, growth, and differentiation of plants from protoplasts (7-IML-1)

    NASA Technical Reports Server (NTRS)

    Rasmussen, Ole

    1992-01-01

    The primary goal of this project is to investigate if microgravity has any influence on growth and differentiation of protoplasts. Formation of new cell walls on rapeseed protoplasts takes place within the first 24 hours after isolation. Cell division can be observed after 2-4 days and formation of cell aggregates after 5-7 days. Therefore, it is possible during the 7 day IML-1 Mission to investigate if cell wall formation, cell division, and cell differentiation are influenced by microgravity. Protoplasts of rapeseeds and carrot will be prepared shortly before launch and injected into 0.6 ml polyethylene bags. Eight bags are placed in an aluminum block inside the ESA Type 1 container. The containers are placed at 4 C in PTCU's and transferred to orbiter mid-deck. At 4 C all cell processes are slowed down, including cell wall formation. Latest access to the shuttle will be 12 hours before launch. In orbit the containers will be transferred from the PTC box to the 22 C Biorack incubator. The installation of a 1 g centrifuge in Biorack will make it possible to distinguish between effects of near weightlessness and effects caused by cosmic radiation and other space flight factors including vibrations. Parallel control experiments will be carried out on the ground. Other aspects of the experiment are discussed.

  16. D-alanine carboxypeptidase activity of Micrococcus lysodeikticus released into the protoplasting medium.

    PubMed

    Linder, R; Salton, M R

    1975-06-16

    Conversion of whole cells of Micrococcus lysodeikticus to protoplasts allowed the release of a soluble form of a D-alanine carboxypeptidase into the protoplasting medium. The enzyme cleaves the terminal D-alanine from the radioactively labelled UDP-N-acetylmuramyl-pentapeptide containing L-lysine as the diamino acid. However, the enzyme is only minimally active in this fraction so that it had to be enriched and partially purified before its properties could be studied. Chromatography on carboxymethyl-Sephadex removed the lysozyme used in the protoplasting of the cells. The material which was unadsorbed to the column was applied to an affinity chromatography column of Ampicillin-Sepharose. Most of the contaminating protein was washed from the column while the D-alanine carboxypeptidase adhered to the resin and could be eluted with 0.5 M Tris-HCl buffer pH 8.6. Some of the properties of the enzymic activity were studied using this preparation. The enzyme was activated by Mg2+ ions with a broad optimum from 15--35 mM. It was maximally active when NaCl at a concentrations of 0.06--0.08 M was added to the assay, and the pH curve was biphasic with an alkaline optimum. The Km for substrate was found to be 0.118 mM. Enzymic activity was completely inhibited by low concentrations of Ampicillin and penicillin G.

  17. Mechanism of Cytokinetic Contractile Ring Constriction in Fission Yeast

    PubMed Central

    Stachowiak, Matthew R.; Laplante, Caroline; Chin, Harvey F.; Guirao, Boris; Karatekin, Erdem; Pollard, Thomas D.; O’Shaughnessy, Ben

    2014-01-01

    SUMMARY Cytokinesis involves constriction of a contractile actomyosin ring. The mechanisms generating ring tension and setting the constriction rate remain unknown, since the organization of the ring is poorly characterized, its tension was rarely measured, and constriction is coupled to other processes. To isolate ring mechanisms we studied fission yeast protoplasts, where constriction occurs without the cell wall. Exploiting the absence of cell wall and actin cortex, we measured ring tension and imaged ring organization, which was dynamic and disordered. Computer simulations based on the amounts and biochemical properties of the key proteins showed that they spontaneously self-organize into a tension-generating bundle. Together with rapid component turnover, the self-organization mechanism continuously reassembles and remodels the constricting ring. Ring constriction depended on cell shape, revealing that the ring operates close to conditions of isometric tension. Thus, the fission yeast ring sets its own tension, but other processes set the constriction rate. PMID:24914559

  18. Novel sporophyte-like plants are regenerated from protoplasts fused between sporophytic and gametophytic protoplasts of Bryopsis plumosa.

    PubMed

    Yamagishi, Takahiro; Hishinuma, Tasuku; Kataoka, Hironao

    2004-06-01

    Protoplasts of the marine coenocytic macrophyte Bryopsis plumosa (Hudson) C. Agardh. [Caulerpales] can easily be obtained by cutting gametophytes or sporophytes with sharp scissors. When a protoplast isolated from a gametophyte was fused with a protoplast isolated from a sporophyte of this alga, it germinated and developed into either one of two completely different forms. One plant form, named Type G, appeared quite similar to a gametophyte, and the other, named Type S, looked similar to a sporophyte. While the Type G plant contained many small nuclei of gametophyte origin together with a single giant nucleus of sporophyte origin, the Type S plant contained many large nuclei of uniform size. These large nuclei in the Type S plant had metamorphosed from the gametophytic nuclei, and were not formed through division of the giant nucleus of sporophyte origin. Fragments of the Type S plant, each having such a large nucleus, developed into creeping filaments that look very similar to sporophytes. While cell walls of gametophytes and Type G plants were stained by Congo-red, those of the thalli of regenerated Type S plants and sporophytes were not stained by the dye. This indicated that the large nuclei of the Type S plant did not express genes for xylan synthesis, which are characteristic of gametophytes. Two-dimensional gel electrophoretic analysis revealed that most of the proteins synthesized in the Type S plant were identical to those of sporophytes. These results strongly suggest that in the Type S plant, the gametophytic nuclei are transformed into sporophyte-like nuclei by an unknown factor(s) produced by the giant nucleus of sporophyte origin and that the transformed nuclei express the set of genes characteristic of sporophytes. Despite morphological similarity, however, the regenerated Type S plant could not produce zoospores, because its large nuclei did not divide normally. The transformed large nuclei of gametophyte origin still seemed to be in the haploid state. Copyright 2004 Springer-Verlag

  19. Site-directed mutagenesis in Petunia × hybrida protoplast system using direct delivery of purified recombinant Cas9 ribonucleoproteins.

    PubMed

    Subburaj, Saminathan; Chung, Sung Jin; Lee, Choongil; Ryu, Seuk-Min; Kim, Duk Hyoung; Kim, Jin-Soo; Bae, Sangsu; Lee, Geung-Joo

    2016-07-01

    Site-directed mutagenesis of nitrate reductase genes using direct delivery of purified Cas9 protein preassembled with guide RNA produces mutations efficiently in Petunia × hybrida protoplast system. The clustered, regularly interspaced, short palindromic repeat (CRISPR)-CRISPR associated endonuclease 9 (CRISPR/Cas9) system has been recently announced as a powerful molecular breeding tool for site-directed mutagenesis in higher plants. Here, we report a site-directed mutagenesis method targeting Petunia nitrate reductase (NR) gene locus. This method could create mutations efficiently using direct delivery of purified Cas9 protein and single guide RNA (sgRNA) into protoplast cells. After transient introduction of RNA-guided endonuclease (RGEN) ribonucleoproteins (RNPs) with different sgRNAs targeting NR genes, mutagenesis at the targeted loci was detected by T7E1 assay and confirmed by targeted deep sequencing. T7E1 assay showed that RGEN RNPs induced site-specific mutations at frequencies ranging from 2.4 to 21 % at four different sites (NR1, 2, 4 and 6) in the PhNR gene locus with average mutation efficiency of 14.9 ± 2.2 %. Targeted deep DNA sequencing revealed mutation rates of 5.3-17.8 % with average mutation rate of 11.5 ± 2 % at the same NR gene target sites in DNA fragments of analyzed protoplast transfectants. Further analysis from targeted deep sequencing showed that the average ratio of deletion to insertion produced collectively by the four NR-RGEN target sites (NR1, 2, 4, and 6) was about 63:37. Our results demonstrated that direct delivery of RGEN RNPs into protoplast cells of Petunia can be exploited as an efficient tool for site-directed mutagenesis of genes or genome editing in plant systems.

  20. Influence of protoplast fusion between two Trichoderma spp. on extracellular enzymes production and antagonistic activity

    PubMed Central

    Hassan, Mohamed M.

    2014-01-01

    Biological control plays a crucial role in grapevine pathogens disease management. The cell-wall degrading enzymes chitinase, cellulase and β-glucanase have been suggested to be essential for the mycoparasitism activity of Trichoderma species against grapevine fungal pathogens. In order to develop a useful strain as a single source of these vital enzymes, it was intended to incorporate the characteristics of two parental fungicides tolerant mutants of Trichoderma belonging to the high chitinase producing species T. harzianum and the high cellulase producing species T. viride, by fusing their protoplasts. The phylogeny of the parental strains was carried out using a sequence of the 5.8S-ITS region. The BLAST of the obtained sequence identified these isolates as T. harzianum and T. viride. Protoplasts were isolated using lysing enzymes and were fused using polyethylene glycol. The fused protoplasts have been regenerated on protoplast regeneration minimal medium supplemented with two selective fungicides. Among the 40 fast growing fusants, 17 fusants were selected based on their enhanced growth on selective media for further studies. The fusant strains were growing 60%–70% faster than the parents up to third generation. All the 17 selected fusants exhibited morphological variations. Some fusant strains displayed threefold increased chitinase enzyme activity and twofold increase in β-glucanase enzyme activity compared to the parent strains. Most fusants showed powerful antagonistic activity against Macrophomin aphaseolina, Pythium ultimum and Sclerotium rolfsii pathogens. Fusant number 15 showed the highest inhibition percentage (92.8%) against M. phaseolina and P. ultimum, while fusant number 9 showed the highest inhibition percentage (98.2%) against the growth of S. rolfsii. A hyphal intertwining and degradation phenomenon was observed by scanning electron microscope. The Trichoderma antagonistic effect against pathogenic fungal mycelia was due to the mycoparasitism effect of the extracellular enzymes. PMID:26019588

  1. Soft material-based microculture system having air permeable cover sheet for the protoplast culture of Nicotiana tabacum.

    PubMed

    Ju, Jong Il; Ko, Jung-Moon; Kim, So Hyeon; Baek, Ju Yeoul; Cha, Hyeon-Cheol; Lee, Sang Hoon

    2006-08-01

    In plant cell culture, the delivery of nutrition and gas (mainly oxygen) to the cells is the most important factor for viability. In this paper, we propose a polydimethylsiloxane (PDMS)-based microculture system that is designed to have good aeration. PDMS is known to have excellent air permeability, and through the experimental method, we investigated the relation between the degree of air delivery and the thickness of the PDMS sheet covering the culture chamber. We determined the proper thickness of the cover sheet, and cultured protoplasts of Nicotiana tabacum in a culture chamber covered with a PDMS sheet having thickness of 400 microm. The cells were successfully divided, and lived well inside the culture chamber for 10 days. In addition, protoplasts were cultured inside the culture chambers covered with the cover glass and the PDMS sheet, respectively, and the microcolonies were formed well inside the PDMS covered chamber after 10 days.

  2. Targeted mutagenesis in Zea mays using TALENs and the CRISPR/Cas system.

    PubMed

    Liang, Zhen; Zhang, Kang; Chen, Kunling; Gao, Caixia

    2014-02-20

    Transcription activator-like effector nucleases (TALENs) and clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated (Cas) systems have emerged as powerful tools for genome editing in a variety of species. Here, we report, for the first time, targeted mutagenesis in Zea mays using TALENs and the CRISPR/Cas system. We designed five TALENs targeting 4 genes, namely ZmPDS, ZmIPK1A, ZmIPK, ZmMRP4, and obtained targeting efficiencies of up to 23.1% in protoplasts, and about 13.3% to 39.1% of the transgenic plants were somatic mutations. Also, we constructed two gRNAs targeting the ZmIPK gene in maize protoplasts, at frequencies of 16.4% and 19.1%, respectively. In addition, the CRISPR/Cas system induced targeted mutations in Z. mays protoplasts with efficiencies (13.1%) similar to those obtained with TALENs (9.1%). Our results show that both TALENs and the CRISPR/Cas system can be used for genome modification in maize. Copyright © 2013. Published by Elsevier Ltd.

  3. Laser microsurgery of higher plant cell walls permits patch-clamp access

    NASA Technical Reports Server (NTRS)

    Henriksen, G. H.; Taylor, A. R.; Brownlee, C.; Assmann, S. M.; Evans, M. L. (Principal Investigator)

    1996-01-01

    Plasma membranes of guard cells in epidermal peels of Vicia faba and Commelina communis can be made accessible to a patch-clamp pipet by removing a small portion (1-3 micrometers in diameter) of the guard cell wall using a microbeam of ultraviolet light generated by a nitrogen laser. Using this laser microsurgical technique, we have measured channel activity across plasma membranes of V. faba guard cells in both cell-attached and isolated patch configurations. Measurements made in the inside-out patch configuration revealed two distinct K(+)-selective channels. Major advantages of the laser microsurgical technique include the avoidance of enzymatic protoplast isolation, the ability to study cell types that have been difficult to isolate as protoplasts or for which enzymatic isolation protocols result in protoplasts not amenable to patch-clamp studies, the maintenance of positional information in single-channel measurements, reduced disruption of cell-wall-mediated signaling pathways, and the ability to investigate intercellular signaling through studies of cells remaining situated within tissue.

  4. Distinct abscisic acid signaling pathways for modulation of guard cell versus mesophyll cell potassium channels revealed by expression studies in Xenopus laevis oocytes

    NASA Technical Reports Server (NTRS)

    Sutton, F.; Paul, S. S.; Wang, X. Q.; Assmann, S. M.; Evans, M. L. (Principal Investigator)

    2000-01-01

    Regulation of guard cell ion transport by abscisic acid (ABA) and in particular ABA inhibition of a guard cell inward K(+) current (I(Kin)) is well documented. However, little is known concerning ABA effects on ion transport in other plant cell types. Here we applied patch clamp techniques to mesophyll cell protoplasts of fava bean (Vicia faba cv Long Pod) plants and demonstrated ABA inhibition of an outward K(+) current (I(Kout)). When mesophyll cell protoplast mRNA (mesophyll mRNA) was expressed in Xenopus laevis oocytes, I(Kout) was generated that displayed similar properties to I(Kout) observed from direct analysis of mesophyll cell protoplasts. I(Kout) expressed by mesophyll mRNA-injected oocytes was inhibited by ABA, indicating that the ABA signal transduction pathway observed in mesophyll cells was preserved in the frog oocytes. Co-injection of oocytes with guard cell protoplast mRNA and cRNA for KAT1, an inward K(+) channel expressed in guard cells, resulted in I(Kin) that was similarly inhibited by ABA. However, oocytes co-injected with mesophyll mRNA and KAT1 cRNA produced I(Kin) that was not inhibited by ABA. These results demonstrate that the mesophyll-encoded signaling mechanism could not substitute for the guard cell pathway. These findings indicate that mesophyll cells and guard cells use distinct and different receptor types and/or signal transduction pathways in ABA regulation of K(+) channels.

  5. Changing patterns of localization of the tobacco mosaic virus movement protein and replicase to the endoplasmic reticulum and microtubules during infection

    NASA Technical Reports Server (NTRS)

    Heinlein, M.; Padgett, H. S.; Gens, J. S.; Pickard, B. G.; Casper, S. J.; Epel, B. L.; Beachy, R. N.; Evans, M. L. (Principal Investigator)

    1998-01-01

    Tobacco mosaic virus (TMV) derivatives that encode movement protein (MP) as a fusion to the green fluorescent protein (MP:GFP) were used in combination with antibody staining to identify host cell components to which MP and replicase accumulate in cells of infected Nicotiana benthamiana leaves and in infected BY-2 protoplasts. MP:GFP and replicase colocalized to the endoplasmic reticulum (ER; especially the cortical ER) and were present in large, irregularly shaped, ER-derived structures that may represent "viral factories." The ER-derived structures required an intact cytoskeleton, and microtubules appeared to redistribute MP:GFP from these sites during late stages of infection. In leaves, MP:GFP accumulated in plasmodesmata, whereas in protoplasts, the MP:GFP was targeted to distinct, punctate sites near the plasma membrane. Treating protoplasts with cytochalasin D and brefeldin A at the time of inoculation prevented the accumulation of MP:GFP at these sites. It is proposed that the punctate sites anchor the cortical ER to plasma membrane and are related to sites at which plasmodesmata form in walled cells. Hairlike structures containing MP:GFP appeared on the surface of some of the infected protoplasts and are reminiscent of similar structures induced by other plant viruses. We present a model that postulates the role of the ER and cytoskeleton in targeting the MP and viral ribonucleoprotein from sites of virus synthesis to the plasmodesmata through which infection is spread.

  6. Somatic hybrid plants of Nicotiana x sanderae (+) N. debneyi with fungal resistance to Peronospora tabacina.

    PubMed

    Patel, Deval; Power, J Brian; Anthony, Paul; Badakshi, Farah; Pat Heslop-Harrison, J S; Davey, Michael R

    2011-10-01

    The genus Nicotiana includes diploid and tetraploid species, with complementary ecological, agronomic and commercial characteristics. The species are of economic value for tobacco, as ornamentals, and for secondary plant-product biosynthesis. They show substantial differences in disease resistance because of their range of secondary products. In the last decade, sexual hybridization and transgenic technologies have tended to eclipse protoplast fusion for gene transfer. Somatic hybridization was exploited in the present investigation to generate a new hybrid combination involving two sexually incompatible tetraploid species. The somatic hybrid plants were characterized using molecular, molecular cytogenetic and phenotypic approaches. Mesophyll protoplasts of the wild fungus-resistant species N. debneyi (2n = 4x = 48) were electrofused with those of the ornamental interspecific sexual hybrid N. × sanderae (2n = 2x = 18). From 1570 protoplast-derived cell colonies selected manually in five experiments, 580 tissues were sub-cultured to shoot regeneration medium. Regenerated plants were transferred to the glasshouse and screened for their morphology, chromosomal composition and disease resistance. Eighty-nine regenerated plants flowered; five were confirmed as somatic hybrids by their intermediate morphology compared with parental plants, cytological constitution and DNA-marker analysis. Somatic hybrid plants had chromosome complements of 60 or 62. Chromosomes were identified to parental genomes by genomic in situ hybridization and included all 18 chromosomes from N. × sanderae, and 42 or 44 chromosomes from N. debneyi. Four or six chromosomes of one ancestral genome of N. debneyi were eliminated during culture of electrofusion-treated protoplasts and plant regeneration. Both chloroplasts and mitochondria of the somatic hybrid plants were probably derived from N. debneyi. All somatic hybrid plants were fertile. In contrast to parental plants of N. × sanderae, the seed progeny of somatic hybrid plants were resistant to infection by Peronospora tabacina, a trait introgressed from the wild parent, N. debneyi. Sexual incompatibility between N. × sanderae and N. debneyi was circumvented by somatic hybridization involving protoplast fusion. Asymmetrical nuclear hybridity was seen in the hybrids with loss of chromosomes, although importantly, somatic hybrids were fertile and stable. Expression of fungal resistance makes these somatic hybrids extremely valuable germplasm in future breeding programmes in ornamental tobacco.

  7. Enhanced resistance to citrus canker in transgenic mandarin expressing Xa21 from rice.

    PubMed

    Omar, Ahmad A; Murata, Mayara M; El-Shamy, Hesham A; Graham, James H; Grosser, Jude W

    2018-04-01

    Genetic engineering approaches offer an alternative method to the conventional breeding of Citrus sp. 'W. Murcott' mandarin (a hybrid of 'Murcott' and an unknown pollen parent) is one of the most commercially important cultivars grown in many regions around the world. Transformation of 'W. Murcott' mandarin was achieved by direct DNA uptake using a protoplast transformation system. DNA construct (pAO3), encoding Green Fluorescent Protein (GFP) and the cDNA of Xa21, a Xanthomonas resistance gene from rice, was used to transform protoplasts of 'W. Murcott' mandarin. Following citrus protoplast culture and regeneration, transformed micro calli were microscopically designated via GFP expression, physically isolated from non-transformed tissue, and cultured on somatic embryogenesis induction medium. More than 150 transgenic embryos were recovered and from them, ten transgenic lines were regenerated and cultured on rooting medium for shoot elongation. Transgenic shoots were micrografted and established in the greenhouse with 3-5 replicates per line. The insertion of Xa21 and GFP was confirmed by PCR and southern blot analysis. GFP expression was verified by fluorescence microscopy and western blot analysis revealed expression of Xa21 although it was variable among transgenic lines, as shown by RT-qPCR. Transgenic plants challenged with the citrus canker pathogen by syringe inoculation showed a reduction in lesion number and bacterial populations within lesions compared to non-transgenic control plants. Transgenic 'W. Murcott' mandarin lines with improved canker resistance via protoplast transformation from embryogenic callus with the Xa21 gene from rice are being evaluated under field conditions to validate the level of resistance.

  8. The density of apical cells of dark-grown protonemata of the moss Ceratodon purpureus

    NASA Technical Reports Server (NTRS)

    Schwuchow, J. M.; Kern, V. D.; Wagner, T.; Sack, F. D.

    2000-01-01

    Determinations of plant or algal cell density (cell mass divided by volume) have rarely accounted for the extracellular matrix or shrinkage during isolation. Three techniques were used to indirectly estimate the density of intact apical cells from protonemata of the moss Ceratodon purpureus. First, the volume fraction of each cell component was determined by stereology, and published values for component density were used to extrapolate to the entire cell. Second, protonemal tips were immersed in bovine serum albumin solutions of different densities, and then the equilibrium density was corrected for the mass of the cell wall. Third, apical cell protoplasts were centrifuged in low-osmolarity gradients, and values were corrected for shrinkage during protoplast isolation. Values from centrifugation (1.004 to 1.015 g/cm3) were considerably lower than from other methods (1.046 to 1.085 g/cm3). This work appears to provide the first corrected estimates of the density of any plant cell. It also documents a method for the isolation of protoplasts specifically from apical cells of protonemal filaments.

  9. Polyamine binding to proteins in oat and Petunia protoplasts

    NASA Technical Reports Server (NTRS)

    Mizrahi, Y.; Applewhite, P. B.; Galston, A. W.

    1989-01-01

    Previous work (A Apelbaum et al. [1988] Plant Physiol 88: 996-998) has demonstrated binding of labeled spermidine (Spd) to a developmentally regulated 18 kilodalton protein in tobacco tissue cultures derived from thin surface layer explants. To assess the general importance of such Spd-protein complexes, we attempted bulk isolation from protoplasts of Petunia and oat (Avena sativa). In Petunia, as in tobacco, fed radioactive Spd is bound to protein, but in oat, Spd is first converted to 1,3,-diaminopropane (DAP), probably by polyamine oxidase action. In oat, binding of DAP to protein depends on age of donor leaf and conditions of illumination and temperature, and the extraction of the DAP-protein complex depends upon buffer and pH. The yield of the DAP-protein complex was maximized by extraction of frozen-thawed protoplasts with a pH 8.8 carbonate buffer containing SDS. Its molecular size, based on Sephacryl column fractionation of ammonium sulfate precipitated material, exceeded 45 kilodaltons. Bound Spd or DAP can be released from their complexes by the action of Pronase, but not DNAse, RNAse, or strong salt solutions, indicating covalent attachment to protein.

  10. Analysis of Microbe-Associated Molecular Pattern-Responsive Synthetic Promoters with the Parsley Protoplast System.

    PubMed

    Kanofsky, Konstantin; Lehmeyer, Mona; Schulze, Jutta; Hehl, Reinhard

    2016-01-01

    Plants recognize pathogens by microbe-associated molecular patterns (MAMPs) and subsequently induce an immune response. The regulation of gene expression during the immune response depends largely on cis-sequences conserved in promoters of MAMP-responsive genes. These cis-sequences can be analyzed by constructing synthetic promoters linked to a reporter gene and by testing these constructs in transient expression systems. Here, the use of the parsley (Petroselinum crispum) protoplast system for analyzing MAMP-responsive synthetic promoters is described. The synthetic promoter consists of four copies of a potential MAMP-responsive cis-sequence cloned upstream of a minimal promoter and the uidA reporter gene. The reporter plasmid contains a second reporter gene, which is constitutively expressed and hence eliminates the requirement of a second plasmid used as a transformation control. The reporter plasmid is transformed into parsley protoplasts that are elicited by the MAMP Pep25. The MAMP responsiveness is validated by comparing the reporter gene activity from MAMP-treated and untreated cells and by normalizing reporter gene activity using the constitutively expressed reporter gene.

  11. Properties of Single K+ and Cl− Channels in Asclepias tuberosa Protoplasts 1

    PubMed Central

    Schauf, Charles L.; Wilson, Kathryn J.

    1987-01-01

    Potassium and chloride channels were characterized in Asclepias tuberosa suspension cell derived protoplasts by patch voltage-clamp. Whole-cell currents and single channels in excised patches had linear instantaneous current-voltage relations, reversing at the Nernst potentials for K+ and Cl−, respectively. Whole cell K+ currents activated exponentially during step depolarizations, while voltage-dependent Cl− channels were activated by hyperpolarizations. Single K+ channel conductance was 40 ± 5 pS with a mean open time of 4.5 milliseconds at 100 millivolts. Potassium channels were blocked by Cs+ and tetraethylammonium, but were insensitive to 4-aminopyridine. Chloride channels had a single-channel conductance of 100 ± 17 picosiemens, mean open time of 8.8 milliseconds, and were blocked by Zn2+ and ethacrynic acid. Whole-cell Cl− currents were inhibited by abscisic acid, and were unaffected by indole-3-acetic acid and 2,4-dichlorophenoxyacetic acid. Since internal and external composition can be controlled, patch-clamped protoplasts are ideal systems for studying the role of ion channels in plant physiology and development. Images Fig. 5 PMID:16665712

  12. Polyamine binding to proteins in oat and Petunia protoplasts.

    PubMed

    Mizrahi, Y; Applewhite, P B; Galston, A W

    1989-01-01

    Previous work (A Apelbaum et al. [1988] Plant Physiol 88: 996-998) has demonstrated binding of labeled spermidine (Spd) to a developmentally regulated 18 kilodalton protein in tobacco tissue cultures derived from thin surface layer explants. To assess the general importance of such Spd-protein complexes, we attempted bulk isolation from protoplasts of Petunia and oat (Avena sativa). In Petunia, as in tobacco, fed radioactive Spd is bound to protein, but in oat, Spd is first converted to 1,3,-diaminopropane (DAP), probably by polyamine oxidase action. In oat, binding of DAP to protein depends on age of donor leaf and conditions of illumination and temperature, and the extraction of the DAP-protein complex depends upon buffer and pH. The yield of the DAP-protein complex was maximized by extraction of frozen-thawed protoplasts with a pH 8.8 carbonate buffer containing SDS. Its molecular size, based on Sephacryl column fractionation of ammonium sulfate precipitated material, exceeded 45 kilodaltons. Bound Spd or DAP can be released from their complexes by the action of Pronase, but not DNAse, RNAse, or strong salt solutions, indicating covalent attachment to protein.

  13. Performance of a kinetic model for intracellular ice formation based on the extent of supercooling.

    PubMed

    Pitt, R E; Chandrasekaran, M; Parks, J E

    1992-06-01

    Cryomicroscopy was used to study the incidence of intracellular ice formation (IIF) in protoplasts isolated from rye (Secale cereale) leaves during subfreezing isothermal periods and in in vitro mature bovine oocytes during cooling at constant rates. IIF in protoplasts occurred at random times during isothermal periods, and the kinetics of IIF were faster as isothermal temperature decreased. Mean IIF times decreased from approximately 1700 s at -4.0 degrees C to less than 1 s at -18.5 degrees C. Total incidence of IIF after 200 s increased from 4% at -4.0 degrees C to near 100% at -15.5 degrees C. IIF behavior in protoplasts was qualitatively similar to that for Drosophila melanogaster embryos over the same temperature ranges (Myers et al., Cryobiology 26, 472-484, 1989), but the kinetics of IIF were about five times faster in protoplasts. IIF observations in linear cooling of bovine oocytes indicated a median IIF temperature of -11 degrees C at 16 degrees C/min and total incidences of 97%, 50%, and 19% at 16, 8, and 4 degrees C/min, respectively. A stochastic model of IIF was developed which preserved certain features of an earlier model (Pitt et al. Cryobiology 28, 72-86, 1991), namely Weibull behavior in IIF temperatures during rapid linear cooling, but with a departure from the concept of a supercooling tolerance. Instead, the new model uses the osmotic state of the cell, represented by the extent of supercooling, as the independent variable governing the kinetics of IIF. Two kinetic parameters are needed for the model: a scale factor tau 0 dictating the sensitivity to supercooling, and an exponent rho dictating the strength of time dependency. The model was fit to the data presented in this study as well as those from Myers et al. and Pitt et al. for D. melanogaster embryos with and without cryoprotectant, and from Toner et al. (Cryobiology 28, 55-71, 1991) for mouse oocytes. In protoplasts, D. melanogaster embryos, and mouse oocytes, the parameters were estimated from IIF times in the early stages of isothermal periods, while the osmotic state of the cell was relatively constant. In bovine oocytes, the parameters were estimated from linear cooling data. Without further calibration, the model was used to predict total IIF incidence under different cooling regimes. For protoplasts, D. melanogaster embryos, and bovine oocytes, the model's predictions were quite accurate compared to the actual data. In mouse oocytes, adjustment of the hydraulic permeability coefficient (Lp) at 0 degree C was required to yield realistic behavior.(ABSTRACT TRUNCATED AT 400 WORDS)

  14. Hanford Works monthly report, October 1952

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1952-11-20

    this document presents a summary of work and progress at the Hanford Engineer works for October 1952. The report is divided into sections by department. A plant wide general summary is included at the beginning of the report, after which the departmental summaries begin. The Manufacturing Department reports plant statistics, and summaries for the Metal Preparation, Reactor and Separation sections. The Engineering Department`s section summaries work for the Technical, Design, and Project Sections. Costs for the various departments are presented in the Financial Department`s summary. The Medical, Radiological Sciences, Utilities and General Services, Employee and Public Relations, and Community Realmore » Estate and Services departments have sections presenting their monthly statistics, work, progress, and summaries.« less

  15. Hanford Works monthly report, February 1953

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1953-03-18

    This document presents a summary of work and progress at the Hanford Engineer Works for February 1953. The report is divided into sections by department. A plant wide general summary is included at the beginning of the report, after which the departmental summaries begin. The Manufacturing Department reports plant statistics, and summaries for the Metal Preparation, Reactor and Separation sections. The Engineering Department`s section summaries work for the Technical, Design, and Project Sections. Costs for the various departments are presented in the Financial Department`s summary. The Medical, Radiological Sciences, Utilities and General Services, Employee and Public Relations, and Community Realmore » Estate and Service departments have sections presenting their monthly statistics, work, progress, and summaries.« less

  16. Hanford Works monthly report, August 1952

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1952-09-24

    This document presents a summary of work and progress at the Hanford Engineer Works for August 1952. The report is divided into sections by department. A plant wide general summary is included at the beginning of the report, after which the departmental summaries begin. The Manufacturing Department reports plant statistics, and summaries for the Metal Preparation, Reactor and Separation sections. The Engineering Department` section summaries work for the Technical, Design, and Project Sections. Costs for the various departments are presented in the Financial Department`s summary. The Medical,Radiological Sciences, Utilities and General Services, Employee and Public Relations, and Community Real Estatemore » and Services departments have sections presenting their monthly statistics, work, progress, and summaries.« less

  17. Hanford Works monthly report, September 1952

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1952-10-20

    This document presents a summary of work and progress at the Hanford Engineer Works for September 1952. The report is divided into sections by department. A plant wide general summary is included at the beginning of the report, after which the departmental summaries begin. The Manufacturing Department reports plant statistics, and summaries for the Metal Preparation, Reactor and Separation sections. The Engineering Department`s section summaries work for the Technical Design, and Project Sections. Costs for the various departments are presented in the Financial Department`s summary. The Medical, Radiological Sciences, Utilities and General Services, Employee and Public Relations, and Community Realmore » Estate and Services departments have sections presenting their monthly statistics, work, progress, and summaries.« less

  18. How do secretory products cross the plant cell wall to be released? A new hypothesis involving cyclic mechanical actions of the protoplast

    PubMed Central

    Paiva, Elder Antônio Sousa

    2016-01-01

    Background In plants, the products of secretory activity leave the protoplast and cross the plasma membrane by means of transporters, fusion with membranous vesicles or, less commonly, as result of disintegration of the cell. These mechanisms do not address an intriguing question: How do secretory products cross the cell wall? Furthermore, how do these substances reach the external surface of the plant body? Such diverse substances as oils, polysaccharides or nectar are forced to cross the cell wall and, in fact, do so. How are chemical materials that are repelled by the cell wall or that are sufficiently viscous to not cross passively released from plant cells? Scope and Conclusions I propose a cell-cycle model developed based on observations of different secreting systems, some unpublished results and an extensive literature review, aiming to understand the processes involved in both the secretory process and the release of secretion products. In the absence of facilitated diffusion, a mechanical action of the protoplast is necessary to ensure that some substances can cross the cell wall. The mechanical action of the protoplast, in the form of successive cycles of contraction and expansion, causes the material accumulated in the periplasmic space to cross the cell wall and the cuticle. This action is particularly relevant for the release of lipids, resins and highly viscous hydrophilic secretions. The proposed cell-cycle model and the statements regarding exudate release will also apply to secretory glands not elaborated upon here. Continuous secretion of several days, as observed in extrafloral nectaries, salt glands and some mucilage-producing glands, is only possible because the process is cyclical. PMID:26929201

  19. Covisualization by computational optical-sectioning microscopy of integrin and associated proteins at the cell membrane of living onion protoplasts

    NASA Technical Reports Server (NTRS)

    Gens, J. S.; Reuzeau, C.; Doolittle, K. W.; McNally, J. G.; Pickard, B. G.; Evans, M. L. (Principal Investigator)

    1996-01-01

    Using higher-resolution wide-field computational optical-sectioning fluorescence microscopy, the distribution of antigens recognized by antibodies against animal beta 1 integrin, fibronectin, and vitronectin has been visualized at the outer surface of enzymatically protoplasted onion epidermis cells and in depectinated cell wall fragments. On the protoplast all three antigens are colocalized in an array of small spots, as seen in raw images, in Gaussian filtered images, and in images restored by two different algorithms. Fibronectin and vitronectin but not beta 1 integrin antigenicities colocalize as puncta in comparably prepared and processed images of the wall fragments. Several control visualizations suggest considerable specifity of antibody recognition. Affinity purification of onion cell extract with the same anti-integrin used for visualization has yielded protein that separates in SDS-PAGE into two bands of about 105-110 and 115-125 kDa. These bands are again recognized by the visualization antibody, which was raised against the extracellular domain of chicken beta 1 integrin, and are also recognized by an antibody against the intracellular domain of chicken beta 1 integrin. Because beta 1 integrin is a key protein in numerous animal adhesion sites, it appears that the punctate distribution of this protein in the cell membranes of onion epidermis represents the adhesion sites long known to occur in cells of this tissue. Because vitronectin and fibronection are matrix proteins that bind to integrin in animals, the punctate occurrence of antigenically similar proteins both in the wall (matrix) and on enzymatically prepared protoplasts reinforces the concept that onion cells have adhesion sites with some similarity to certain kinds of adhesion sites in animals.

  20. Somatic hybrid plants between Lycopersicon esculentum and Solanum lycopersicoides.

    PubMed

    Handley, L W; Nickels, R L; Cameron, M W; Moore, P P; Sink, K C

    1986-02-01

    Leaf mesophyll protoplasts of Lycopersicon esculentum (2n=2x=24) were fused with suspension culture-derived protoplasts of Solanum lycopersicoides (2n=2x=24) and intergeneric somatic hybrid plants were regenerated following selective conditions. A two phase selection system was based on the inability of S. lycopersicoides protoplasts to divide in culture in modified medium 8E and the partial inhibition of L. esculentum protoplasts by the PEG/DMSO fusion solution. At the p-calli stage, putative hybrids were visually selected based on their hybrid vigor and lime-green coloration in contrast to slower growing parental calli characterized by a watery, whitish-brown coloration. Early identification of the eight hybrid plants studied was facilitated by isozyme analysis of leaf tissue samples taken from plants in vitro at the rooting stage. Regenerated plants growing in planting medium were further verified for hybridity by 5 isozymes marking 7 loci on 5 chromosomes in tomato. These included Skdh-1 mapped to chromosome 1 of tomato, Pgm-2 on chromosome 4, Got-2 and Got-3 on chromosome 7, Got-4 on chromosome 8, and Pgi-1 and Pgdh-2 both on chromosome 12. Fraction I protein small subunits further confirmed the hybrid nature of the plants with bands of both parents expressed in all hybrids. The parental chloroplasts could not be differentiated by the isoelectric points of the large subunit. Seven of the eight somatic hybrids had a chromosome number ranging from the expected 2n=4x=48 to 2n=68. Mixoploid root-tip cells containing 48, 53, 54 or 55 chromosomes for two of the hybrids were also observed.

  1. Hanford Atomic Products Operation monthly report, March 1954

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1954-04-23

    This document presents a summary of work and progress at the Hanford Engineer Works for March 1954. The report is divided into sections by department. A plant wide general summary is included at the beginning of the report, after which the departmental summaries begin. The Manufacturing Department reports plant statistics, and summaries for the Metal Preparation, Reactor and Separation sections. The Engineering Department`s section summaries work for the Technical, Design, and Project Sections. Costs for the various departments are presented in the Financial Department`s summary. The Medical, Radiological Sciences, Utilities and General Services, Employee and Public Relations, and Community Realmore » Estate and Service departments have sections presenting their monthly statistics, work, progress, and summaries.« less

  2. Hanford Atomic Products Operation monthly report, June 1954

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1954-07-26

    This document presents a summary of work and progress at the Hanford Engineer Works for June 1954. The report is divided into sections by department. A plant wide general summary is included at the beginning of the report, after which the departmental summaries begin. The Manufacturing Department reports plant statistics, and summaries for the Metal Preparation, Reactor and Separation sections. The Engineering Department`s section summaries work for the Technical, Design, and Project Sections. Costs for the various departments are presented in the Financial Department`s summary. The Medical, Radiological Sciences, Utilities and General Services, Employee and Public Relations, and Community Realmore » Estate and Services departments have sections presenting their monthly statistics, work, progress, and summaries.« less

  3. Hanford Atomic Products Operation monthly report, May 1954

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1954-06-22

    This document presents a summary of work and progress at the Hanford Engineer Works for May 1954. The report is divided into sections by department. A plant wide general summary is included at the beginning of the report, after which the departmental summaries begin. The Manufacturing Department reports plant statistics, and summaries for the Metal Preparation, Reactor and Separation sections. The Engineering Department`s section summaries work for the Technical, Design, and Project Sections. Costs for the various departments are presented in the Financial Department`s summary. The Medical, Radiological Science, Utilities and General Services, Employee and Public Relations, and Community Realmore » Estate and Services departments have sections presenting their monthly statistics, work, progress, and summaries.« less

  4. Hanford Atomic Products Operation monthly report, October 1953

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1953-11-20

    This document presents a summary of work and progress at the Hanford Engineer Works for October 1953. The report is divided into sections by department. A plant wide general summary is included at the beginning of the report, after which the departmental summaries begin. The Manufacturing Department reports plant statistics, and summaries for the Metal Preparation, Reactor and Separation sections. The Engineering Department`s section summaries work for the Technical, Design, and Project Sections. Costs for the various departments are presented in the Financial Department`s summary. The Medical, Radiological Sciences, Utilities and General Services. Employee and Public Relations, and Community Realmore » Estate and Service departments have sections presenting their monthly statistics, work, progress, and summaries.« less

  5. Hanford Atomic Products Operation monthly report, May 1953

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    This document presents a summary of work and progress at the Hanford Engineer Works for May 1953. The report is divided into sections by department. A plant wide general summary is included at the beginning of the report, after which the departmental summaries begin. The Manufacturing Department reports plant statistics, and summaries for the Metal Preparation, Reactor and Separation sections. The Engineering Department`s section summaries work for the Technical, Design, and Project Sections. Costs for the various departments are presented in the Financial Department`s summary. The Medical, Radiological Sciences, Utilities and General Services, Employee and Public Relations, and Community Realmore » Estate and Services departments have sections presenting their monthly statistics, work, progress, and summaries.« less

  6. Hanford Atomic Products Operation monthly report, July 1953

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1953-08-20

    This document presents a summary of work and progress at the Hanford Engineer Works for July 1953. The report is divided into sections by department. A plant wide general summary is included at the beginning of the report, after which the departmental summaries begin. The Manufacturing Department reports plant statistics, and summaries for the Metal Preparation, Reactor and Separation sections. The Engineering Department`s section summaries work for the Technical, Design, and Project Sections. Costs for the various departments are presented in the Financial Department`s summary. The Medical, Radiological Sciences, Utilities and General Services, Employee and Public Relations, and Community Realmore » Estate and Services departments have sections presenting their monthly statistics, work, progress, and summaries.« less

  7. Hanford Atomic Products Operation monthly report for September 1954

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1954-10-25

    This document presents a summary of work and progress at the Hanford Engineer Works for September 1954. The report is divided into sections by department. A plant wide general summary is included at the beginning of the report, after which the departmental summaries begin. The Manufacturing Department reports plant statistics, and summaries for the Metal Preparation, Reactor and Separation sections. The Engineering Department`s section summaries work for the Technical, Design, and Project Sections. Costs for the various departments are presented in the Financial Department`s summary. The Medical, Radiological Sciences, Utilities and General Services, Employee and Public Relations, and Community Realmore » Estate and Services departments have sections presenting their monthly statistics, work, progress, and summaries.« less

  8. Hanford Atomic Products Operation monthly report, June 1953

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1953-07-22

    This document presents a summary of work and progress at the Hanford Engineer Works for June 1953. The report is divided into sections by department. A plant wide general summary is included at the beginning of the report, after which the departmental summaries begin. The Manufacturing Department reports plant statistics, and summaries for the Metal Preparation, Reactor and Separation sections. The Engineering Department`s section summaries work the Technical, Design, and Project Sections. Costs for the various departments are presented in the Financial Department`s summary. The Medical, Radiological Sciences, Utilities and General Services, Employee and Public Relations, and Community Real Estatemore » and Services departments have sections presenting their monthly statistics, work, progress, and summaries.« less

  9. Hanford Atomic Products Operation monthly report, December 1953

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1954-01-22

    This document presents a summary of work and progress at the Hanford Engineer Works for December 1953. The report is divided into sections by department. A plant wide general summary is included at the beginning of the report, after which the departmental summaries begin. The Manufacturing Department reports plant statistics, and summaries for the Metal Preparation, Reactor and Separation sections. The Engineering Department`s section summaries work for the Technical, Design, and Project Sections. Costs for the various departments are presented in the Financial Department`s summary. The Medical, Radiological Sciences, Utilities and General Services, Employee and Public Relations, and Community Realmore » Estate and Services departments have sections presenting their monthly statistics, work, progress, and summaries.« less

  10. [In vitro regeneration and applications using vegetable cell and tissue culture].

    PubMed

    Jordán, M

    1990-10-01

    Plant cells by means of their totipotency and aided by in vitro culture techniques can be induced to perform morphogenesis leading to somatic embryoids and massive clonal multiplication; microspores or pollen can be triggered to recover haploid plants, then characters expressed via haploidy can be selected and fixed. Protoplasts from different species can lead to recombinations. We report here work done on Carica pubescens, where somatic embryoids were obtained from cells; in Prunus avium androgenesis leading to pollen calli was triggered, while plants were recovered from Nicotiana tabacum anthers. Fusion products were obtained using C. pubescens and C. papaya protoplasts, leading up to calli and shoots.

  11. Protoplast formation and yeast cell-wall structure. The action of the enzymes of the snail, Helix pomatia

    PubMed Central

    Anderson, F. B.; Millbank, J. W.

    1966-01-01

    1. The digestive juice of the snail Helix pomatia was used in the study of the degradation of isolated cell-wall preparations from a strain of Saccharomyces carlsbergensis. 2. The crude enzyme system was fractionated by gel filtration and the activities of the more specific fractions thus obtained were examined. 3. Results are discussed with respect to (a) the nature of various factors that are essential for protoplast formation and cell-wall dissolution and (b) structures envisaged in yeast cell walls that are responsible for the observed variations in susceptibility to attack by snail juice. PMID:5964965

  12. Uncapped mRNA introduced into tobacco protoplasts can be imported into the nucleus and is trapped by leptomycin B.

    PubMed

    Stuger, Rogier; Forreiter, Christoph

    2004-08-01

    The mechanism of nuclear export of RNAs in yeast and animal cells is rapidly being uncovered, but RNA export in plants has received little attention. We introduced capped and uncapped fluorescent mRNAs into tobacco (Nicotiana plumbaginifolia) protoplasts and studied their cellular localization. Following insertion, capped transcripts were found in the cytoplasm, while uncapped messengers transiently appeared in the nucleus in about one-quarter to one-third of the cells. These mRNAs were trapped by the nuclear export-inhibiting drug leptomycin B, pointing to an export mechanism in plants similar to Rev-NES-mediated RNP export in other organisms.

  13. Effect of the Specific Toxin in Helminthosporium victoriae on Host Cell Membranes 1

    PubMed Central

    Samaddar, K. R.; Scheffer, R. P.

    1968-01-01

    Helminthosporium victoriae toxin, which affects only hosts of the toxin-producing fungus, causes loss of electrolytes from roots, leaves, and coleoptiles of treated plants. Root hair cells lost the ability to plasmolyze after 20 minutes exposure to toxin in solution; comparable resistant cells retained plasmolytic ability during 3 hours exposure. Toxin stopped uptake of exogenous amino acids and Pi by susceptible but not by resistant tissue. Incorporation of 32P into organic-P and 14C-amino acids into protein was blocked in susceptible but not in resistant tissue. Apparent free space increased in susceptible but not in resistant roots. The increase was evident within 30 minutes, and reached 80% free space after 2 hours exposure to toxin. When cell wall-free protoplasts were exposed to 0.16 μg toxin/ml, protoplasmic streaming stopped and all plasma membranes of susceptible protoplasts broke within 1 hour. Resistant protoplasts were not affected significantly. Data support the hypothesis of a primary lesion of toxin in the plasma membrane. Effects on synthesis could result from lack of transport of exogenous solutes to sites of synthesis. It is possible that all other observed effects of toxin are secondary to membrane damage. PMID:16656731

  14. Cre-lox Univector acceptor vectors for functional screening in protoplasts: analysis of Arabidopsis donor cDNAs encoding ABSCISIC ACID INSENSITIVE1-Like protein phosphatases

    PubMed Central

    Jia, Fan; Gampala, Srinivas S.L.; Mittal, Amandeep; Luo, Qingjun; Rock, Christopher D.

    2009-01-01

    The 14,200 available full length Arabidopsis thaliana cDNAs in the Universal Plasmid System (UPS) donor vector pUNI51 should be applied broadly and efficiently to leverage a “functional map-space” of homologous plant genes. We have engineered Cre-lox UPS host acceptor vectors (pCR701- 705) with N-terminal epitope tags in frame with the loxH site and downstream from the maize Ubiquitin promoter for use in transient protoplast expression assays and particle bombardment transformation of monocots. As an example of the utility of these vectors, we recombined them with several Arabidopsis cDNAs encoding Ser/Thr protein phosphatase type 2C (PP2Cs) known from genetic studies or predicted by hierarchical clustering meta-analysis to be involved in ABA and stress responses. Our functional results in Zea mays mesophyll protoplasts on ABA-inducible expression effects on the Late Embryogenesis Abundant promoter ProEm:GUS reporter were consistent with predictions and resulted in identification of novel activities of some PP2Cs. Deployment of these vectors can facilitate functional genomics and proteomics and identification of novel gene activities. PMID:19499346

  15. Factors affecting the efficient transformation of Colletotrichum species

    USGS Publications Warehouse

    Redman, Regina S.; Rodriguez, Rusty J.

    1994-01-01

    Factors affecting the efficient transformation of Colletotrichum species. Experimental Mycology, 18, 230-246. Twelve isolates representing four species of Colletotrichum were transformed either by enhanced protoplast, restriction enzyme-mediated integration (REMI), or electroporation-mediated protocols. The enhanced protoplast transformation protocol resulted in 100- and 50-fold increases in the transformation efficiencies of Colletotrichum lindemuthianum and C. magna , respectively. REMI transformation involved the use of Hin dIII and vector DNA linearized with HindIII to increase the number of integration events and potential gene disruptions in the fungal genome. Combining the enhanced protoplast and the REMI protocols resulted in a 22-fold increase in the number of hygromycin/nystatin-resistant mutants in C. lindemuthianum . Electroporation-mediated transformation was performed on mycelial fragments and spores of four Colletotrichum species, resulting in efficiencies of up to 1000 transformants/μg DNA. The pHA1.3 vector which confers hygromycin resistance contains telomeric sequences from Fusarium oxysporum , transforms by autonomous replication and genomic integration, and was essential for elevated transformation efficiencies of 100 to 10,000 transformants/μg DNA. Modifications of pHA1.3 occurred during bacterial amplification and post fungal transformation resulting in plasmids capable of significantly elevated transformation efficiencies in C. lindemuthianum.

  16. Somatic hybrid plants of Nicotiana × sanderae (+) N. debneyi with fungal resistance to Peronospora tabacina

    PubMed Central

    Patel, Deval; Power, J. Brian; Anthony, Paul; Badakshi, Farah; (Pat) Heslop-Harrison, J. S.; Davey, Michael R.

    2011-01-01

    Background and Aims The genus Nicotiana includes diploid and tetraploid species, with complementary ecological, agronomic and commercial characteristics. The species are of economic value for tobacco, as ornamentals, and for secondary plant-product biosynthesis. They show substantial differences in disease resistance because of their range of secondary products. In the last decade, sexual hybridization and transgenic technologies have tended to eclipse protoplast fusion for gene transfer. Somatic hybridization was exploited in the present investigation to generate a new hybrid combination involving two sexually incompatible tetraploid species. The somatic hybrid plants were characterized using molecular, molecular cytogenetic and phenotypic approaches. Methods Mesophyll protoplasts of the wild fungus-resistant species N. debneyi (2n = 4x = 48) were electrofused with those of the ornamental interspecific sexual hybrid N. × sanderae (2n = 2x = 18). From 1570 protoplast-derived cell colonies selected manually in five experiments, 580 tissues were sub-cultured to shoot regeneration medium. Regenerated plants were transferred to the glasshouse and screened for their morphology, chromosomal composition and disease resistance. Key Results Eighty-nine regenerated plants flowered; five were confirmed as somatic hybrids by their intermediate morphology compared with parental plants, cytological constitution and DNA-marker analysis. Somatic hybrid plants had chromosome complements of 60 or 62. Chromosomes were identified to parental genomes by genomic in situ hybridization and included all 18 chromosomes from N. × sanderae, and 42 or 44 chromosomes from N. debneyi. Four or six chromosomes of one ancestral genome of N. debneyi were eliminated during culture of electrofusion-treated protoplasts and plant regeneration. Both chloroplasts and mitochondria of the somatic hybrid plants were probably derived from N. debneyi. All somatic hybrid plants were fertile. In contrast to parental plants of N. × sanderae, the seed progeny of somatic hybrid plants were resistant to infection by Peronospora tabacina, a trait introgressed from the wild parent, N. debneyi. Conclusions Sexual incompatibility between N. × sanderae and N. debneyi was circumvented by somatic hybridization involving protoplast fusion. Asymmetrical nuclear hybridity was seen in the hybrids with loss of chromosomes, although importantly, somatic hybrids were fertile and stable. Expression of fungal resistance makes these somatic hybrids extremely valuable germplasm in future breeding programmes in ornamental tobacco. PMID:21880657

  17. Light-enhanced dark respiration in leaves, isolated cells and protoplasts of various types of C4 plants.

    PubMed

    Parys, Eugeniusz; Jastrzebski, Hubert

    2006-04-01

    The rate of respiratory CO2 evolution from the leaves of Zea mays, Panicum miliaceum, and Panicum maximum, representing NADP-ME, NAD-ME, and PEP-CK types of C4 plants, respectively, was increased by approximately two to four times after a period of photosynthesis. This light-enhanced dark respiration (LEDR) was a function of net photosynthetic rate specific to plant species, and was depressed by 1% O2. When malate, aspartate, oxaloacetate or glycine solution at 50 mM concentration was introduced into the leaves instead of water, the rate of LEDR was enhanced, far less in Z. mays (by 10-25%) than in P. miliaceum (by 25-35%) or P. maximum (by 40-75%). The enhancement of LEDR under glycine was relatively stable over a period of 1 h, whereas the remaining metabolites caused its decrease following a transient increase. The metabolites reduced the net photosynthesis rate in the two Panicum species, but not in Z. mays, where this process was stimulated by glycine. The bundle sheath cells from P. miliaceum exhibited a higher rate of LEDR than those of Z. mays and P. maximum. Glycine had no effect on the respiration rate of the cells, but malate increased in cells of Z. mays and P. miliaceum by about 50% and 30%, respectively. With the exception of aspartate, which stimulated both the O2 evolution and O2 uptake in P. maximum, the remaining metabolites reduced photosynthetic O2 evolution from bundle sheath cells in Panicun species. The net O2 exchange in illuminated cells of Z. mays did not respond to CO2 or metabolites. Leaf mesophyll protoplasts of Z. mays and P. miliaceum, and bundle sheath protoplasts of Z. mays, which are unable to fix CO2 photosynthetically, also produced LEDR, but the mesophyll protoplasts, compared with bundle sheath protoplasts, required twice the time of illumination to obtain the maximal rate. The results suggest that the substrates for LEDR in C4 plants are generated during a period of illumination not only via the Calvin cycle reactions, but also by the conversion of endogenous compounds present in leaf cells. The stimulation of LEDR under glycine is discussed in relation to its direct or indirect effect on mitochondrial respiration.

  18. Hanford Works monthly report, December 1952

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1953-01-23

    This document presents a summary of work and progress at the Hanford Engineer Works for December 1952. The report is divided into sections by department. A plant wide general summary is included at the beginning of the report, after which the departmental summaries begin. The Manufacturing Department reports plant statistics, and summaries for the Metal Preparation, Reactor and Separation sections. The Engineering Department`s section summarizes work for the Technical, Design, and Project Sections. Costs for the various departments are presented in the Financial Department`s summary. The Medical, Radiological Sciences, Utilities and General Services, Employee and Public Relations, and Community Realmore » Estate and Services departments have sections presenting their monthly statistics, work, progress, and summaries.« less

  19. Hanford Atomic Products Operation monthly report, January 1955

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1955-02-21

    This document presents a summary of work and progress at the Hanford Engineer Works for January 1955. The report is divided into sections by department. A plant wide general summary is included at the beginning of the report, after which the departmental summaries begin. The Manufacturing Department reports plant statistics, and summaries for the Metal Preparation, Reactor and Separation sections. The Engineering Department`s section summarizes work for the Technical Design, and Project Sections. Costs for the various departments are presented in the Financial department`s summary. The Medical, Radiological Sciences, Utilities and General Services, Employee and Public Relations, and Community Realmore » Estate and Services departments have sections presenting their monthly statistics, work, progress, and summaries.« less

  20. Hanford Atomic Products Operation monthly report for April 1955

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1955-05-23

    This document presents a summary of work and progress at the Hanford Engineer Works for April 1955. The report is divided into sections by department. A plant wide general summary is included at the beginning of the report, after which the departmental summaries begin. The Manufacturing Department reports plant statistics, and summaries for the Metal Preparation, Reactor and Separation sections. The Engineering Department`s section summarizes work for the Technical, Design, and Project Sections. Costs for the various departments are presented in the Financial Department`s summary. The Medical, Radiological Sciences, Utilities and General Services, Employee and Public Relations, and Community Realmore » Estate and Services departments have sections presenting their monthly statistics, work, progress, and summaries.« less

  1. Monthly report Hanford Atomic Products Operation, July 1954

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1954-08-20

    This document presents a summary of work and progress at the Hanford Engineer Works for July 1954. The report is divided into sections by department. A plant wide general summary is included at the beginning of the report, after which the departmental summaries begin. The Manufacturing Department reports plant statistics, and summaries for the Metal Preparation, Reactor and Separation sections. The Engineering Department`s section summarizes work for the Technical, Design, and Project sections. Costs for the various departments are presented in the Financial Department`s summary. The Medical, Radiological Sciences, Utilities and General Services, Employee and Public Relations, and Community Realmore » Estate and Services Departments have sections presenting their monthly statistics, work, progress, and summaries.« less

  2. Hanford Atomic Products Operation monthly report, August 1956

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1956-09-28

    This document presents a summary of work and progress at the Hanford Engineer Works for August 1956. The report is divided into sections by department. A plant wide general summary is included at the beginning of the report, after which the departmental summaries begin. The Manufacturing Department reports plant statistics, and summaries for the Metal Preparation, Reactor and Separation sections. The Engineering Department`s section summarizes work for the Technical, Design, and Project Sections. Costs for the various departments are presented in the Financial Department`s summary. The Medical, Radiological Sciences, Utilities and General Sciences, Employee and Public Relations, and Community Realmore » Estate and Services departments have sections presenting their monthly statistics, work, progress, and summaries.« less

  3. Hanford Atomic Products Operation monthly report for May 1956

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1956-06-21

    This document presents a summary of work and progress at the Hanford Engineer Works for May, 1956. The report is divided into sections by department. A plant wide general summary is included at the beginning of the report, after which the departmental summaries begin. The Manufacturing department reports plant statistics, and summaries for the Metal Preparation, Reactor and Separation sections. The Engineering Department`s section summarizes work for the Technical, Design, and Project Sections. Costs for the various departments are presented in the financial Department`s summary. The Medical, Radiological Sciences, Utilities and General Services, Employee and Public Relations, and Community Realmore » Estate and Services departments have sections presenting their monthly statistics, work, progress, and summaries.« less

  4. Hanford Atomic Products Operation monthly report, September 1955

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1955-10-27

    This document presents a summary of work and progress at the Hanford Engineer Works for September 1955. The report is divided into sections by department. A plant wide general summary is included at the beginning of the report, after which the departmental summaries begin. The Manufacturing Department reports plant statistics, and summaries for the Metal Preparation, Reactor and Separation sections. The Engineering Department`s section summarizes work for the Technical, Design, and Project Sections. Costs for the various departments are presented in the Financial Department`s summary. The Medical, Radiological Sciences, Utilities and General Services, Employee and Public Relations, and Community Realmore » Estate and Services departments have sections presenting their monthly statistics, work, progress, and summaries.« less

  5. Hanford Atomic Products Operation monthly report, March 1955

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1955-04-20

    This document presents a summary of work and progress at the Hanford Engineer Works for March 1955. The report is divided into sections by department. A plant wide general summary is included at the beginning of the report, after which the departmental summaries begin. The Manufacturing Department reports plant statistics, and summaries for the Metal Preparation, Reactor and Separation sections. The Engineering Department`s section summarizes work for the Technical, Design, and Project Sections. Costs for the various departments are presented in the Financial Department`s summary. The Medical, Radiological Sciences, Utilities and General Services, Employee and Public Relations, and Community Realmore » Estate and Services departments have sections presenting their monthly statistics, work, progress, and summaries.« less

  6. Hanford Atomic Products Operation monthly report, November 1955

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1955-12-30

    This document presents a summary of work and progress at the Hanford Engineer Works for November 1955. The report is divided into sections by department. A plant wide general summary is included at the beginning of the report, after which the departmental summaries begin. The Manufacturing Department reports plant statistics, and summaries for the Metal Preparation, Reactor and Separation sections. The Engineering Department`s section summarizes work for the Technical, Design, and Project Sections. Costs for the various departments are presented in the Financial Department`s summary. The Medical, Radiological Sciences, Utilities and General Services, Employee and Public Relations, and Community Realmore » Estate and Services departments have sections presenting their monthly statistics, work, progress, and summaries.« less

  7. Hanford Atomic Products Operation monthly report, August 1955

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1955-09-27

    This document presents a summary of work and progress at the Hanford Engineer Works for August 1955. The report is divided into sections by department. A plant wide general summary is included at the beginning of the report, after which the departmental summaries begin. The Manufacturing Department reports plant statistics, and summaries for the Metal Preparation, Reactor and Separation sections. The Engineering Department`s section summarizes work for the Technical, Design, and Project Sections. Costs for the various departments are presented in the Financial Department`s summary. The Medical, Radiological Sciences, Utilities and General Sciences, Employee and Public Relations, and Community Realmore » Estate and Services departments have sections presenting their monthly statistics, work, progress, and summaries.« less

  8. Hanford Atomic Products Operation monthly report for December 1955

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1956-01-30

    This document presents a summary of work and progress at the Hanford Engineer Works for December 1955. The report is divided into sections by department. A plant wide general summary is included at the beginning of the report, after which the departmental summaries begin. The Manufacturing Department reports plant statistics, and summaries for the Metal Preparation, Reactor and Separation sections. The Engineering Department`s section summarizes work for the Technical, Design, and Project Sections. Costs for the various departments are presented in the Financial Department`s summary. The Medical, Radiological Sciences, Utilities and General Services, Employee and Public Relations, and Community Realmore » Estate and Services departments have sections presenting their monthly statistics, work, progress, and summaries.« less

  9. Hanford Atomic Products Operation monthly report, October 1955

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1955-11-30

    This document presents a summary of work and progress at the Hanford Engineer works for October, 1955. The report is divided into sections by department. A plant wide general summary is included at the beginning of the report, after which the departmental summaries begin. The Manufacturing Department reports plant statistics, and summaries for the Metal Preparation, Reactor and Separation sections. The Engineering Department`s section summarizes work for the Technical, Design, and Project Sections. Costs for the various departments are presented in the Financial Department`s summary. The Medical, Radiological Sciences, Utilities and General Services, Employee and Public Relations, and community Realmore » Estate and Services departments have sections presenting their monthly statistics, work, progress, and summaries.« less

  10. Hanford Atomic Products for Operation monthly report, February 1955

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1955-03-18

    This document presents a summary of work and progress at the Hanford Engineer Works for February 1955. The report is divided into sections by department. A plant wide general summary is included at the beginning of the report, after which the departmental summaries begin. The Manufacturing Department reports plant statistics, and summaries for the Metal Preparation, Reactor and Separation sections. The Engineering Department`s section summarizes work for the Technical, Design, and Project Sections. Costs for the various departments are presented in the Financial Department`s summary. The Medical, Radiological Sciences, Utilities and General Services, Employee and Public Relations, and Community Realmore » Estate and Services departments have sections presenting their monthly statistics, work, progress, and summaries.« less

  11. Hanford Atomic Products Operation monthly report, May 1955

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1955-06-23

    This document presents a summary of work and progress at the Hanford Engineer Works for May 1955. The report is divided into sections by department. A plant wide general summary is included at the beginning of the report, after which the departmental summaries begin. The Manufacturing Department reports plant statistics, and summaries for the Metal Preparation, Reactor and Separation sections. The Engineering Department`s section summarizes work for the Technical, Design, and Project Sections. Costs for the various departments are presented in the Financial Department`s summary. The Medical, Radiological Sciences, Utilities and General Services, Employee and Public Relations, and Community Realmore » Estate and Services departments have sections presenting their monthly statistics, work, progress, and summaries.« less

  12. Hanford Atomic Products Operation monthly report, July 1955

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1955-08-26

    This document presents a summary of work and progress at the Hanford Engineer Works for July 1955. The report is divided into sections by department. A plant wide general summary is included at the beginning of the report, after which the departmental summaries begin. The Manufacturing Department reports plant statistics, and summaries for the Metal Preparation, Reactor and Separation sections. The Engineering Department`s section summarizes work for the Technical, Design, and Project sections. Costs for the various departments are presented in the Financial Department`s summary. The Medical, Radiological Sciences, Utilities and General Services, Employee and Public Relations, and Community Realmore » Estate and services departments have sections presenting their monthly statistics, work, progress, and summaries.« less

  13. Hanford Atomic Products Operation monthly report, October 1954

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1954-11-24

    This document presents a summary of work and progress at the Hanford Engineer Works for October 1954. The report is divided into sections by department. A plant wide general summary is included at the beginning of the report, after which the departmental summaries begin. The Manufacturing Department reports plant statistics, and summaries for the Metal Preparation, Reactor and Separation sections. The Engineering Department`s section summarizes work for the Technical, Design, and Project Sections. Costs for the various departments are presented in the Financial Department`s summary. The Medical, Radiological Sciences, Utilities and General Services, Employee and Public Relations, and Community Realmore » Estate and Services departments have sections presenting their monthly statistics, work, progress, and summaries.« less

  14. Hanford Atomic Products Operation monthly report, December 1954

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1955-01-25

    This document presents a summary of work and progress at the Hanford Engineer Works for December 1954. The report is divided into sections by department. A plant wide general summary is included at the beginning of the report, after which the departmental summaries begin. The Manufacturing Department reports plant statistics, and summaries for the Metal Preparation, Reactor and Separation sections. The Engineering Department`s section summarizes work for the Technical, Design, and Project Sections. Costs for the various departments are presented in the Financial Department`s summary. The Medical, Radiological Sciences, Utilities and General Services, Employee and Public Relations, and Community Realmore » Estate and Services departments have sections presenting their monthly statistics, work, progress, and summaries.« less

  15. Hanford Atomic Products Operation monthly report, August 1954

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1954-09-17

    This document presents a summary of work and progress at the Hanford Engineer Works for August 1954. The report is divided into sections by department. A plant wide general summary is included at the beginning of the report, after which the departmental summaries begin. The Manufacturing Department report plant statistics, and summaries for the Metal Preparation, Reactor and Separation sections. The Engineering Department`s section summarizes work for the Technical, Design, and Project Sections. Costs for the various departments are presented in the Financial Department`s summary. The Medical, Radiological Sciences, Utilities, and General Services, Employee and Public Relations, and Community Realmore » Estate and Services departments have sections presenting their monthly statistics, work, progress, and summaries.« less

  16. Hanford Atomic Products Operation monthly report, August 1953

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1953-09-18

    This document presents a summary of work and progress at the Hanford Engineer Works for August, 1953. The report is divided into sections by department. A plant wide general summary is included at the beginning of the report, after which the departmental summaries begin. The Manufacturing Department reports plant statistics, and summaries for the Metal Preparation, Reactor and Separation sections. The Engineering Department`s section summarizes work for the Technical, Design, and Project Sections. Costs for the various departments are presented in the Financial Department`s summary. The Medical, Radiological Sciences, Utilities and General Services, Employee and Public Relations, and Community Realmore » Estate and Services departments have sections presenting their monthly statistics, work, progress, and summaries.« less

  17. Moving California Ahead: An Executive Summary Concerning Two Commission Higher Education Long-Range Planning Reports, Providing for Progress and Policy for Progress.

    ERIC Educational Resources Information Center

    California State Postsecondary Education Commission, Sacramento.

    This is an executive summary of two long-range higher education planning reports completed at the outset of the 21st century by the California Postsecondary Education Commission. They are "Providing for Progress: California Higher Education Enrollment Demand and Resources into the 21st Century" and the companion "Policy for…

  18. 45 CFR 1307.2 - Definitions.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... progress of the children it serves that have been combined to provide summary information about groups of... other groups of children such as dual language learners, or to provide summary information by specific... children's status and progress across domains of language and literacy development, cognition and general...

  19. 45 CFR 1307.2 - Definitions.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... progress of the children it serves that have been combined to provide summary information about groups of... other groups of children such as dual language learners, or to provide summary information by specific... children's status and progress across domains of language and literacy development, cognition and general...

  20. 45 CFR 1307.2 - Definitions.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... progress of the children it serves that have been combined to provide summary information about groups of... other groups of children such as dual language learners, or to provide summary information by specific... children's status and progress across domains of language and literacy development, cognition and general...

  1. Subcellular Distribution of O-Acetylserine(thiol)lyase in Cauliflower (Brassica oleracea L.) Inflorescence.

    PubMed

    Rolland, N; Droux, M; Douce, R

    1992-03-01

    The subcellular localization of O-acetyiserine(thiol)lyase (EC 4.2.99.8) in nongreen tissue from higher plants has been studied using purified proplastids, mitochondria, and protoplasts from cauliflower (Brassica oleracea L.) buds as a source of subcellular fractions. O-Acetylserine(thiol)lyase has been detected in both organelles (proplastids and mitochondria) and a cytosolic extract obtained by protoplast fractionation. We confirmed these observations, demonstrating that a form of the enzyme different in global charge and separated from others by anion-exchange chromatography corresponded to each subcellular location. Our observations are consistent with the need for cysteine biosynthesis in each subcellular compartment where the synthesis of proteins occurs.

  2. Subcellular Distribution of O-Acetylserine(thiol)lyase in Cauliflower (Brassica oleracea L.) Inflorescence

    PubMed Central

    Rolland, Norbert; Droux, Michel; Douce, Roland

    1992-01-01

    The subcellular localization of O-acetyiserine(thiol)lyase (EC 4.2.99.8) in nongreen tissue from higher plants has been studied using purified proplastids, mitochondria, and protoplasts from cauliflower (Brassica oleracea L.) buds as a source of subcellular fractions. O-Acetylserine(thiol)lyase has been detected in both organelles (proplastids and mitochondria) and a cytosolic extract obtained by protoplast fractionation. We confirmed these observations, demonstrating that a form of the enzyme different in global charge and separated from others by anion-exchange chromatography corresponded to each subcellular location. Our observations are consistent with the need for cysteine biosynthesis in each subcellular compartment where the synthesis of proteins occurs. ImagesFigure 1 PMID:16668766

  3. An Efficient PEG/CaCl₂-Mediated Transformation Approach for the Medicinal Fungus Wolfiporia cocos.

    PubMed

    Sun, Qiao; Wei, Wei; Zhao, Juan; Song, Jia; Peng, Fang; Zhang, Shaopeng; Zheng, Yonglian; Chen, Ping; Zhu, Wenjun

    2015-09-01

    Sclerotia of Wolfiporia cocos are of medicinal and culinary value. The genes and molecular mechanisms involved in W. cocos sclerotial formation are poorly investigated because of the lack of a suitable and reproducible transformation system for W. cocos. In this study, a PEG/ CaCl₂-mediated genetic transformation system for W. cocos was developed. The promoter Pgpd from Ganoderma lucidum effectively drove expression of the hygromycin B phosphotransferase gene in W. cocos, and approximately 30 transformants were obtained per 10 μg DNA when the protoplast suspension density was 10(6) protoplasts/ml. However, no transformants were obtained under the regulation of the PtrpC promoter from Aspergillus nidulans.

  4. Laboratory course on Streptomyces genetics and secondary metabolism.

    PubMed

    Siitonen, Vilja; Räty, Kaj; Metsä-Ketelä, Mikko

    2016-09-10

    The "Streptomyces genetics and secondary metabolism" laboratory course gives an introduction to the versatile soil dwelling Gram-positive bacteria Streptomyces and their secondary metabolism. The course combines genetic modification of Streptomyces; growing of the strain and protoplast preparation, plasmid isolation by alkaline lysis and phenol precipitation, digestions, and ligations prior to protoplast transformation, as well as investigating the secondary metabolites produced by the strains. Thus, the course is a combination of microbiology, molecular biology, and chemistry. After the course the students should understand the relationship between genes, proteins, and the produced metabolites. © 2016 by The International Union of Biochemistry and Molecular Biology, 44(5):492-499, 2016. © 2016 The International Union of Biochemistry and Molecular Biology.

  5. Differential effects of human and plant N-acetylglucosaminyltransferase I (GnTI) in plants.

    PubMed

    Henquet, Maurice; Heinhuis, Bas; Borst, Jan Willem; Eigenhuijsen, Jochem; Schreuder, Mariëlle; Bosch, Dirk; van der Krol, Alexander

    2010-08-01

    In plants and animals, the first step in complex type N-glycan formation on glycoproteins is catalyzed by N-acetylglucosaminyltransferase I (GnTI). We show that the cgl1-1 mutant of Arabidopsis, which lacks GnTI activity, is fully complemented by YFP-labeled plant AtGnTI, but only partially complemented by YFP-labeled human HuGnTI and that this is due to post-transcriptional events. In contrast to AtGnTI-YFP, only low levels of HuGnTI-YFP protein was detected in transgenic plants. In protoplast co-transfection experiments all GnTI-YFP fusion proteins co-localized with a Golgi marker protein, but only limited co-localization of AtGnTI and HuGnTI in the same plant protoplast. The partial alternative targeting of HuGnTI in plant protoplasts was alleviated by exchanging the membrane-anchor domain with that of AtGnTI, but in stably transformed cgl1-1 plants this chimeric GnTI still did not lead to full complementation of the cgl1-1 phenotype. Combined, the results indicate that activity of HuGnTI in plants is limited by a combination of reduced protein stability, alternative protein targeting and possibly to some extend to lower enzymatic performance of the catalytic domain in the plant biochemical environment.

  6. The effect of the external medium on the gravity-induced polarity of cytoplasmic streaming in Chara corallina (Characeae).

    PubMed

    Staves, M P; Wayne, R; Leopold, A C

    1997-11-01

    Gravity induces a polarity of cytoplasmic streaming in vertical internodal cells of Chara such that the downwardly directed stream moves faster than the upwardly directed stream. In order to determine whether the statolith theory (in which intracellular sedimenting particles are responsible for gravity sensing) or the gravitational pressure theory (in which the entire protoplast acts as the gravity sensor) best explain the gravity response in Chara internodal cells, we controlled the physical properties of the external medium, including density and osmolarity, with impermeant solutes and examined the effect on the polarity of cytoplasmic streaming. As the density of the external medium is increased, the polarity of cytoplasmic streaming decreases and finally disappears when the density of the external medium is equal to that of the cell (1015 kg/m3). A further increase in the density of the external medium causes a reversal of the gravity response. These results are consistent with the gravitational pressure theory of gravity sensing since the buoyancy of the protoplast is dependent on the difference between the density of the protoplast and the external medium, and are inconsistent with the statolith theory since the buoyancy of intracellular particles are unaffected by changes in the external medium.

  7. The effect of the external medium on the gravity-induced polarity of cytoplasmic streaming in Chara corallina (Characeae)

    NASA Technical Reports Server (NTRS)

    Staves, M. P.; Wayne, R.; Leopold, A. C.

    1997-01-01

    Gravity induces a polarity of cytoplasmic streaming in vertical internodal cells of Chara such that the downwardly directed stream moves faster than the upwardly directed stream. In order to determine whether the statolith theory (in which intracellular sedimenting particles are responsible for gravity sensing) or the gravitational pressure theory (in which the entire protoplast acts as the gravity sensor) best explain the gravity response in Chara internodal cells, we controlled the physical properties of the external medium, including density and osmolarity, with impermeant solutes and examined the effect on the polarity of cytoplasmic streaming. As the density of the external medium is increased, the polarity of cytoplasmic streaming decreases and finally disappears when the density of the external medium is equal to that of the cell (1015 kg/m3). A further increase in the density of the external medium causes a reversal of the gravity response. These results are consistent with the gravitational pressure theory of gravity sensing since the buoyancy of the protoplast is dependent on the difference between the density of the protoplast and the external medium, and are inconsistent with the statolith theory since the buoyancy of intracellular particles are unaffected by changes in the external medium.

  8. Evidence of the Insensitivity of the α-inc Allele to the Function of the Homothallic Genes in Saccharomyces Yeasts

    PubMed Central

    Takano, Isamu; Arima, Kenji

    1979-01-01

    The possible function of the α-inc allele (an α mating-type allele that is insensitive to the function of the homothallic gene system) was investigated by means of protoplast fusion. The fusion of protoplasts prepared from haploid strains of α-inc HO HMα HMa and α ho hmα HMa gave rise mainly to nonmating clones (58 of 64 isolates) and a few clones (six of 64 isolates) showing α mating type. Thirty of the 58 nonmating clones showed the diploid cell size and 28 clones had a larger cell size. Tetrad analysis of the nonmating clones with diploid cell size indicated that they were a/α-inc diploid; the normal α allele in α/α-inc cells was preferentially switched to an a allele. This observation further indicated that the HO/ho HMα/hmα HMa/HMa genotype is effective for the conversion of the α to a and that the inconvertibility of the α-inc allele is due to the insensitivity of the mating-type allele to the functional combination of the homothallic genes. It was suspected that fusion products larger than diploid cells might have been caused by multiple fusion of protoplasts. PMID:17248884

  9. Gravitropism and gravimorphism during regeneration from protoplasts of the moss Ceratodon purpureus (Hedw.) Brid

    NASA Technical Reports Server (NTRS)

    Wagner, T. A.; Sack, F. D.

    1998-01-01

    Wild-type (WT) protonemata of the moss Ceratodon purpureus grow upwards in darkness (negative gravitropism), whereas protonemata of the mutant, wrong-way response (wwr-1) grow down. Since Ceratodon protoplasts regenerate to form new protonemata, we analyzed whether the direction of filament emergence was influenced by gravity (gravimorphism) and determined the cytological events that correlated with the onset of gravitropism in WT and wwr-1 filaments formed de novo. In the WT the direction of filament emergence appeared to be gravimorphic as more than 66% of the new filaments emerged above the horizontal. In contrast, the direction of filament emergence was random in wwr-1. Tip-growing cells of both genotypes became gravitropic within a total of one to two cell divisions. Gravitropic curvature in wwr-1 was opposite in direction to that of WT, and the timing of curvature was comparable, indicating that the wwr-1 mutation acts during the onset of gravitropic competence. In time-lapse studies of both genotypes, neither a plastid-free zone nor obvious and extensive plastid sedimentation characteristic of mature dark-grown protonemata was observed in the new filaments prior to gravitropic curvature. Thus, it appears that these latter two features are not required for gravitropism in new protonemal filaments from protoplasts.

  10. Tagging potato leafroll virus with the jellyfish green fluorescent protein gene.

    PubMed

    Nurkiyanova, K M; Ryabov, E V; Commandeur, U; Duncan, G H; Canto, T; Gray, S M; Mayo, M A; Taliansky, M E

    2000-03-01

    A full-length cDNA corresponding to the RNA genome of Potato leafroll virus (PLRV) was modified by inserting cDNA that encoded the jellyfish green fluorescent protein (GFP) into the P5 gene near its 3' end. Nicotiana benthamiana protoplasts electroporated with plasmid DNA containing this cDNA behind the 35S RNA promoter of Cauliflower mosaic virus became infected with the recombinant virus (PLRV-GFP). Up to 5% of transfected protoplasts showed GFP-specific fluorescence. Progeny virus particles were morphologically indistinguishable from those of wild-type PLRV but, unlike PLRV particles, they bound to grids coated with antibodies to GFP. Aphids fed on extracts of these protoplasts transmitted PLRV-GFP to test plants, as shown by specific fluorescence in some vascular tissue and epidermal cells and subsequent systemic infection. In plants agroinfected with PLRV-GFP cDNA in pBIN19, some cells became fluorescent and systemic infections developed. However, after either type of inoculation, fluorescence was mostly restricted to single cells and the only PLRV genome detected in systemically infected tissues lacked some or all of the inserted GFP cDNA, apparently because of naturally occurring deletions. Thus, intact PLRV-GFP was unable to move from cell to cell. Nevertheless, PLRV-GFP has novel potential for exploring the initial stages of PLRV infection.

  11. The assembly of cellulose microfibrils in Valonia macrophysa Kütz.

    PubMed

    Itoh, T; Brown, R M

    1984-03-01

    The assembly of cellulose microfibrils was investigated in artificially induced protoplasts of the alga, Valonia macrophysa (Siphonocladales). Primary-wall microfibrills, formed within 72 h of protoplast induction, are randomly oriented. Secondary-wall lamellae, which are produced within 96 h after protoplast induction, have more than three orientations of highly ordered microfibrils. The innermost, recently deposited micofibrils are not parallel with the cortical microtubules, thus indicating a more indirect role of microtubules in the orientation of microfibrils. Fine filamentous structures with a periodicity of 5.0-5.5 nm and the dimensions of actin were observed adjacent to the plasma membrane. Linear cellulose-terminal synthesizing complexes (TCs) consisting of three rows, each with 30-40 particles, were observed not only on the E fracture (EF) but also on P fracture (PF) faces of the plasma membrane. The TC appears to span both faces of the bimolecular leaflet. The average length of the TC is 350 nm, and the number of TCs per unit area during primary-wall synthesis is 1 per μm(2). Neither paired TCs nor granule bands characteristic of Oocystis were observed. Changes in TC structure and distribution during the conversion from primary- to secondary-wall formation have been described. Cellulose microfibril assembly in Valonia is discussed in relation to the process among other eukaryotic systems.

  12. Uptake, sequestration and tolerance of cadmium at cellular levels in the hyperaccumulator plant species Sedum alfredii

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tian, Shengke; Xie, Ruohan; Wang, Haixin

    Sedum alfredii is one of a few plant species known to hyperaccumulate cadmium (Cd). Uptake, localization, and tolerance of Cd at cellular levels in shoots were compared in hyperaccumulating (HE) and non-hyperaccumulating (NHE) ecotypes of Sedum alfredii. X-ray fluorescence images of Cd in stems and leaves showed only a slight Cd signal restricted within vascular bundles in the NHEs, while enhanced localization of Cd, with significant tissue- and age-dependent variations, was detected in HEs. In contrast to the vascular-enriched Cd in young stems, parenchyma cells in leaf mesophyll, stem pith and cortex tissues served as terminal storage sites for Cdmore » sequestration in HEs. Kinetics of Cd transport into individual leaf protoplasts of the two ecotypes showed little difference in Cd accumulation. However, far more efficient storage of Cd in vacuoles was apparent in HEs. Subsequent analysis of cell viability and hydrogen peroxide levels suggested that HE protoplasts exhibited higher resistance to Cd than those of NHE protoplasts. These results suggest that efficient sequestration into vacuoles, as opposed to rapid transport into parenchyma cells, is a pivotal process in Cd accumulation and homeostasis in shoots of HE S. alfredii. This is in addition to its efficient root-to-shoot translocation of Cd.« less

  13. Pregnancy and HIV disease progression: a systematic review and meta-analysis.

    PubMed

    Calvert, Clara; Ronsmans, Carine

    2015-02-01

    To assess whether pregnancy accelerates HIV disease progression. Studies comparing progression to HIV-related illness, low CD4 count, AIDS-defining illness, HIV-related death, or any death in HIV-infected pregnant and non-pregnant women were included. Relative risks (RR) for each outcome were combined using random effects meta-analysis and were stratified by antiretroviral therapy (ART) availability. 15 studies met the inclusion criteria. Pregnancy was not associated with progression to HIV-related illness [summary RR: 1.32, 95% confidence interval (CI): 0.66-2.61], AIDS-defining illness (summary RR: 0.97, 95% CI: 0.74-1.25) or mortality (summary RR: 0.97, 95% CI: 0.62-1.53), but there was an association with low CD4 counts (summary RR: 1.41, 95% CI: 0.99-2.02) and HIV-related death (summary RR: 1.65, 95% CI: 1.06-2.57). In settings where ART was available, there was no evidence that pregnancy accelerated progress to HIV/AIDS-defining illnesses, death and drop in CD4 count. In settings without ART availability, effect estimates were consistent with pregnancy increasing the risk of progression to HIV/AIDS-defining illnesses and HIV-related or all-cause mortality, but there were too few studies to draw meaningful conclusions. In the absence of ART, pregnancy is associated with small but appreciable increases in the risk of several negative HIV outcomes, but the evidence is too weak to draw firm conclusions. When ART is available, the effects of pregnancy on HIV disease progression are attenuated and there is little reason to discourage healthy HIV-infected women who desire to become pregnant from doing so. © 2014 John Wiley & Sons Ltd.

  14. Educational Model for Social Service Administration and Management. Summary Progress Report.

    ERIC Educational Resources Information Center

    Wright, Marjorie Brown

    This paper constitutes a summary progress report on a short-term training course designed to provide social work bachelor's degree practitioners with the knowledge and skills necessary for administrative and managerial positions. Increasingly, social work graduates have reported moving into social service administration and managerial positions…

  15. Zinc compartmentation in root, transport into xylem, and absorption into leaf cells in the hyperaccumulating species of Sedum alfredii Hance.

    PubMed

    Yang, Xiaoe; Li, Tingqiang; Yang, Juncheng; He, Zhenli; Lu, Lingli; Meng, Fanhua

    2006-06-01

    Sedum alfredii Hance can accumulate Zn in shoots over 2%. Leaf and stem Zn concentrations of the hyperaccumulating ecotype (HE) were 24- and 28-fold higher, respectively, than those of the nonhyperaccumulating ecotype (NHE), whereas 1.4-fold more Zn was accumulated in the roots of the NHE. Approximately 2.7-fold more Zn was stored in the root vacuoles of the NHE, and thus became unavailable for loading into the xylem and subsequent translocation to shoot. Long-term efflux of absorbed 65Zn indicated that 65Zn activity was 6.8-fold higher in shoots but 3.7-fold lower in roots of the HE. At lower Zn levels (10 and 100 microM), there were no significant differences in 65Zn uptake by leaf sections and intact leaf protoplasts between the two ecotypes except that 1.5-fold more 65Zn was accumulated in leaf sections of the HE than in those of the NHE after exposure to 100 microM for 48 h. At 1,000 microM Zn, however, approximately 2.1-fold more Zn was taken up by the HE leaf sections and 1.5-fold more 65Zn taken up by the HE protoplasts as compared to the NHE at exposure times >16 h and >10 min, respectively. Treatments with carbonyl cyanide m-chlorophenylhydrazone (CCCP) or ruptured protoplasts strongly inhibited 65Zn uptake into leaf protoplasts for both ecotypes. Citric acid and Val concentrations in leaves and stems significantly increased for the HE, but decreased or had minimal changes for the NHE in response to raised Zn levels. These results indicate that altered Zn transport across tonoplast in the root and stimulated Zn uptake in the leaf cells are the major mechanisms involved in the strong Zn hyperaccumulation observed in S. alfredii H.

  16. A new approach for breeding low-temperature-resistant Volvariella volvacea strains: Genome shuffling in edible fungi.

    PubMed

    Zhu, Ziping; Wu, Xiao; Lv, Beibei; Wu, Guogan; Wang, Jinbin; Jiang, Wei; Li, Peng; He, Jianhua; Chen, Jianzhong; Chen, Mingjie; Bao, Dapeng; Zhang, Jinsong; Tan, Qi; Tang, Xueming

    2016-09-01

    Volvariella volvacea is difficult to store fresh because of the lack of low-temperature resistance. Many traditional mutagenic strategies have been applied in order to select out strains resistant to low temperature, but few commercially efficient strains have been produced. In order to break through the bottleneck of traditional breeding and significantly improve low-temperature resistance of the edible fungus V. volvacea, strains resistant to low temperature were constructed by genome shuffling. The optimum conditions of V. volvacea strain mutation, protoplast regeneration, and fusion were determined. After protoplasts were treated with 1% (v/v) ethylmethylsulfonate (EMS), 40 Sec of ultraviolet (UV) irradiation, 600 Gy electron beam implantation, and 750 Gy 60 Co-γ irradiation, separately, the lethality was within 70%-80%, which favored generating protoplasts being used in following forward mutation. Under these conditions, 16 strains of V. volvacea mutated by EMS, electron beam, UV irradiation, and 60 Co-γ irradiation were obtained. The 16 mutated protoplasts were selected to serve as the shuffling pool based on their excellent low-temperature resistance. After four rounds of genome shuffling and low-temperature resistance testing, three strains (VF 1 , VF 2 , and VF 3 ) with high genetic stability were screened. VF 1 , VF 2 , and VF 3 significantly enhanced fruit body shelf life to 20, 28, and 28 H at 10 °C, respectively, which exceeded 25%, 75%, and 75%, respectively, compared with the storage time of V23, the most low-temperature-resistant strain. Genome shuffling greatly improved the low-temperature resistance of V. volvacea, and shortened the course of screening required to generate desirable strains. To our knowledge, this is the first paper to apply genome shuffling to breeding new varieties of mushroom, and offers a new approach for breeding edible fungi with optimized phenotype. © 2015 International Union of Biochemistry and Molecular Biology, Inc.

  17. Betaine aldehyde dehydrogenase isozymes of spinach

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hanson, A.D.; Weretilnyk, E.A.; Weigel, P.

    1986-04-01

    Betaine is synthesized in spinach chloroplasts via the pathway Choline ..-->.. Betaine Aldehyde ..-->.. Betaine; the second step is catalyzed by betaine aldehyde dehydrogenase (BADH). The subcellular distribution of BADH was determined in leaf protoplast lysates; BADH isozymes were separated by 6-9% native PAGE. The chloroplast stromal fraction contains a single BADH isozyme (number1) that accounts for > 80% of the total protoplast activity; the extrachloroplastic fraction has a minor isozyme (number2) which migrates more slowly than number1. Both isozymes appear specific for betaine aldehyde, are more active with NAD than NADP, and show a ca. 3-fold activity increase inmore » salinized leaves. The phenotype of a natural variant of isozyme number1 suggests that the enzyme is a dimer.« less

  18. Problems and potentialities of cultured plant cells in retrospect and prospect

    NASA Technical Reports Server (NTRS)

    Steward, F. C.; Krikorian, A. D.

    1979-01-01

    The past, present and expected future accomplishments and limitations of plant cell and tissue culture are reviewed. Consideration is given to the pioneering insights of Haberlandt in 1902, the development of culture techniques, and past work on cell division, cell and tissue growth and development, somatic embryogenesis, and metabolism and respiration. Current activity in culture media and technique development for plant regions, organs, tissues, cells, protoplasts, organelles and embryos, totipotency, somatic embryogenesis and clonal propagation under normal and space conditions, biochemical potentialities, and genetic engineering is surveyed. Prospects for the investigation of the induced control of somatic cell division, the division of isolated protoplasts, the improvement of haploid cell cultures, liquid cultures for somatic embryogenesis, and the genetic control of development are outlined.

  19. From Cytosol to the Apoplast: The Hygromycin Phosphotransferase (HYG(R)) Model in Arabidopsis.

    PubMed

    Zhang, Haiyan; Li, Jinjin

    2016-01-01

    The process by which proteins are secreted via endoplasmic reticulum (ER)/Golgi-independent mechanism is conveniently called unconventional protein secretion. Recent studies have revealed that unconventional protein secretion operates in plants, but little is known about its underlying mechanism and function. This chapter provides methods we have used to analyze unconventional character of hygromycin phosphotransferase (HYG(R)) secretion in plant cells. Following isolation of protoplasts from HYG (R) -GFP-transgenic plants and incubation with brefeldin A (BFA), an inhibitor of conventional secretory pathway, we easily obtain protein extracts from protoplasts and culture medium separately. These proteins are separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), followed by Western blot analysis with anti-GFP antibodies.

  20. Allotetraploid hybrids between citrus and seven related genera produced by somatic hybridization.

    PubMed

    Grosser, J W; Mourao-Fo, F A; Gmitter, F G; Louzada, E S; Jiang, J; Baergen, K; Quiros, A; Cabasson, C; Schell, J L; Chandler, J L

    1996-04-01

    We have developed an efficient protoplast-fusion method to produce somatic hybrid allopolyploid plants that combine Citrus with seven related genera, including four that are sexually incompatible. In this paper we report the creation of 18 new allotetraploid hybrids of Citrus, including ten among sexually incompatible related genera, that may have direct cultivar potential as improved citrus rootstocks. All hybrids were confirmed by cytological and RAPD analyses. If fertile, the attributes of these hybrids may be amenable to further genetic manipulation by breeding at the tetraploid level. Wide somatic hybridization of Citrus via protoplast fusion bypasses biological barriers to the natural allopolyploidization of Citrus, and creates new evolutionary opportunities that would be difficult or impossible to achieve by natural or conventional hybridization.

  1. Expression of human growth hormone by the eukaryotic alga, Chlorella.

    PubMed

    Hawkins, R L; Nakamura, M

    1999-06-01

    A method to use Chlorella to express a recombinant heterologous protein that can be recovered from the extracellular medium has been developed. Plasmids are constructed with an extracellular secretion signal sequence inserted between a promoter region and a gene for human growth hormone (hGH). The plasmids also contain a Kanr region which confers resistance to the antibiotic G418. Protoplasts are prepared by enzymatic treatment, and the plasmid is introduced by incubation of the protoplasts with polyethylene glycol and dimethyl sulfoxide. Cells are then grown in the presence of G418, and the medium is collected from 6 days after transfection. hGH is measured by immunoassay, and values for expressed hGH of about 200-600 ng/ml are obtained.

  2. Progress Report 2013. Turnaround Arts Initiative

    ERIC Educational Resources Information Center

    Stoelinga, Sara Ray; Joyce, Katie; Silk, Yael

    2013-01-01

    This interim progress report provides a look at Turnaround Arts schools in their first year, including: (1) a summary of the evaluation design and research questions; (2) a preliminary description of strategies used to introduce the arts in Turnaround Arts schools; and (3) a summary of school reform indicators and student achievement data at…

  3. Methods for suspension culture, protoplast extraction, and transformation of high-biomass yielding perennial grass Arundo donax.

    PubMed

    Pigna, Gaia; Dhillon, Taniya; Dlugosz, Elizabeth M; Yuan, Joshua S; Gorman, Connor; Morandini, Piero; Lenaghan, Scott C; Stewart, C Neal

    2016-12-01

    Arundo donax L. is a promising biofuel feedstock in the Mediterranean region. Despite considerable interest in its genetic improvement, Arundo tissue culture and transformation remains arduous. The authors developed methodologies for cell- and tissue culture and genetic engineering in Arundo. A media screen was conducted, and a suspension culture was established using callus induced from stem axillary bud explants. DBAP medium, containing 9 µM 2,4-D and 4.4 µM BAP, was found to be the most effective medium among those tested for inducing cell suspension cultures, which resulted in a five-fold increase in tissue mass over 14 days. In contrast, CIM medium containing 13 µM 2,4-D, resulted in just a 1.4-fold increase in mass over the same period. Optimized suspension cultures were superior to previously-described solidified medium-based callus culture methods for tissue mass increase. Suspension cultures proved to be very effective for subsequent protoplast isolation. Protoplast electroporation resulted in a 3.3 ± 1.5% transformation efficiency. A dual fluorescent reporter gene vector enabled the direct comparison of the CAMV 35S promoter with the switchgrass ubi2 promoter in single cells of Arundo. The switchgrass ubi2 promoter resulted in noticeably higher reporter gene expression compared with that conferred by the 35S promoter in Arundo. Copyright © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Exploration of jasmonate signalling via automated and standardized transient expression assays in tobacco cells.

    PubMed

    De Sutter, Valerie; Vanderhaeghen, Rudy; Tilleman, Sofie; Lammertyn, Freya; Vanhoutte, Isabelle; Karimi, Mansour; Inzé, Dirk; Goossens, Alain; Hilson, Pierre

    2005-12-01

    Although sequence information and genome annotation are improving at an impressive pace, functional ontology is still non-existent or rudimentary for most genes. In this regard, transient expression assays are very valuable for identification of short functional segments in particular pathways, because they can be performed rapidly and at a scale unattainable in stably transformed tissues. Vectors were constructed and protocols developed for systematic transient assays in plant protoplasts. To enhance throughput and reproducibility, protoplast treatments were performed entirely by a liquid-handling robot in multiwell plates, including polyethylene glycol/Ca2+ cell transfection with plasmid mixtures, washes and lysis. All transcriptional readouts were measured using a dual firefly/Renilla luciferase assay, in which the former was controlled by a reporter promoter and the latter by the 35S CaMV promoter, which served as internal normalization standard. The automated protocols were suitable for transient assays in protoplasts prepared from cell cultures of Nicotiana tabacum Bright Yellow-2 and Arabidopsis thaliana. They were implemented in a screen to discover potential regulators of genes coding for key enzymes in nicotine biosynthesis. Two novel tobacco transcription factors were found, NtORC1 and NtJAP1, that positively regulate the putrescine N-methyltransferase (PMT) promoter. In addition, combinatorial tests showed that these two factors act synergistically to induce PMT transcriptional activity. The development and use of high-throughput plant transient expression assays are discussed.

  5. New evidence about the relationship between water channel activity and calcium in salinity-stressed pepper plants.

    PubMed

    Cabañero, Francisco J; Martínez-Ballesta, M Carmen; Teruel, José A; Carvajal, Micaela

    2006-02-01

    This study, of how Ca2+ availability (intracellular, extracellular or linked to the membrane) influences the functionality of aquaporins of pepper (Capsicum annuum L.) plants grown under salinity stress, was carried out in plants treated with NaCl (50 mM), CaCl2 (10 mM), and CaCl2 (10 mM) + NaCl (50 mM). For this, water transport through the plasma membrane of isolated protoplasts, and the involvement of aquaporins and calcium (extracellular, intracellular and linked to the membrane) has been determined. After these treatments, it could be seen that the calcium concentration was reduced in the apoplast, in the cells and on the plasma membrane of roots of pepper plants grown under saline conditions; these concentrations were increased or restored when extra calcium was added to the nutrient solution. Protoplasts extracted from plants grown under Ca2+ starvation showed no aquaporin functionality. However, for the protoplasts to which calcium was added, an increase of aquaporin functionality of the plasma membrane was observed [osmotic water permeability (Pf) inhibition after Hg addition]. Interestingly, when verapamil (a Ca2+ channel blocker) was added, no functionality was observed, even when Ca2+ was added with verapamil. Therefore, calcium seems to be involved in plasma membrane aquaporin regulation via a chain of processes within the cell but not by alteration of the stability of the plasma membrane.

  6. Organization of cytoskeleton controls the changes in cytosolic calcium of cold-shocked Nicotiana plumbaginifolia protoplasts.

    PubMed

    Mazars, C; Thion, L; Thuleau, P; Graziana, A; Knight, M R; Moreau, M; Ranjeva, R

    1997-11-01

    Using Nicotiana plumbaginifolia constitutively expressing the recombinant bioluminescent calcium indicator, aequorin, it has been previously demonstrated that plant cells react to cold-shock by an immediate rise in cytosolic calcium. Such an opportune system has been exploited to address the regulatory pathway involved in the calcium response. For this purpose, we have used protoplasts derived from N. plumbaginifolia leaves that behave as the whole plant but with a better reproducibility. By both immunodetecting cytoskeletal components on membrane ghosts and measuring the relative change in cytosolic calcium, we demonstrate that the organization of the cytoskeleton has profound influences on the calcium response. The disruption of the microtubule meshwork by various active drugs, such as colchicin, oryzalin and vinblastin, leads to an important increase in the cytosolic calcium (up to 400 nM) in cold-shocked protoplasts over control. beta-Lumicolchicin, an inactive analogue of colchicin, is ineffective either on cytoplasmic calcium increase or on microtubule organization. A microfilament disrupting drug, cytochalasin D, exerts a slight stimulatory effect, whereas the simultaneous disruption of microtubule and microfilament meshworks results in a dramatic increase in the calcium response to cold-shock. The results described in the present paper illustrate the role of the intracellular organization and, more specifically, the role of cytoskeleton in controlling the intensity of calcium response to an extracellular stimulus.

  7. Synthesis of viral DNA forms in Nicotiana plumbaginifolia protoplasts inoculated with cassava latent virus (CLV); evidence for the independent replication of one component of the CLV genome.

    PubMed Central

    Townsend, R; Watts, J; Stanley, J

    1986-01-01

    Totipotent leaf mesophyll protoplasts of Nicotiana plumbaginifolia, Viviani were inoculated with cassava latent virus (CLV) or with full length copies of CLV genomic DNAs 1 and 2 excised from replicative forms of M13 clones. Virus specific DNAs began to appear 48-72h after inoculation with virus or cloned DNAs, coincident with the onset of host cell division. Infected cells accumulated supercoiled forms of DNAs 1 and 2 as well as progeny single-stranded (ss) virion (+) sense DNAs representing each component of the genome. Both supercoiled and ss molecules were synthesised by cells inoculated with cloned DNA 1 alone but DNA 2 failed to replicate independently. Images PMID:3951986

  8. A Summary Report of Iowa's Review of PreK-6 Reading Assessments for Universal Screening and Progress

    ERIC Educational Resources Information Center

    Iowa Department of Education, 2013

    2013-01-01

    This document contains summary information for the Iowa Department of Education's review of PreK-6th grade reading assessments for the purposes of Universal Screening and Progress Monitoring. It is intended to provide general information to help inform decisions about selecting assessments for use as a part of Iowa's Response to Intervention…

  9. The Genetic Programming of Industrial Microorganisms.

    ERIC Educational Resources Information Center

    Hopwood, David A.

    1981-01-01

    Traces the development of the field of industrial microbial genetics, describing a range of techniques for genetic programing. Includes a discussion of site-directed mutagenesis, protoplast fusion, and recombinant DNA manipulations. (CS)

  10. The cyclic nucleotide gated cation channel AtCNGC10 traffics from the ER via Golgi vesicles to the plasma membrane of Arabidopsis root and leaf cells.

    PubMed

    Christopher, David A; Borsics, Tamas; Yuen, Christen Y L; Ullmer, Wendy; Andème-Ondzighi, Christine; Andres, Marilou A; Kang, Byung-Ho; Staehelin, L Andrew

    2007-09-19

    The cyclic nucleotide-gated ion channels (CNGCs) maintain cation homeostasis essential for a wide range of physiological processes in plant cells. However, the precise subcellular locations and trafficking of these membrane proteins are poorly understood. This is further complicated by a general deficiency of information about targeting pathways of membrane proteins in plants. To investigate CNGC trafficking and localization, we have measured Atcngc5 and Atcngc10 expression in roots and leaves, analyzed AtCNGC10-GFP fusions transiently expressed in protoplasts, and conducted immunofluorescence labeling of protoplasts and immunoelectron microscopic analysis of high pressure frozen leaves and roots. AtCNGC10 mRNA and protein levels were 2.5-fold higher in roots than leaves, while AtCNGC5 mRNA and protein levels were nearly equal in these tissues. The AtCNGC10-EGFP fusion was targeted to the plasma membrane in leaf protoplasts, and lightly labeled several intracellular structures. Immunofluorescence microscopy with affinity purified CNGC-specific antisera indicated that AtCNGC5 and AtCNGC10 are present in the plasma membrane of protoplasts. Immunoelectron microscopy demonstrated that AtCNGC10 was associated with the plasma membrane of mesophyll, palisade parenchyma and epidermal cells of leaves, and the meristem, columella and cap cells of roots. AtCNCG10 was also observed in the endoplasmic reticulum and Golgi cisternae and vesicles of 50-150 nm in size. Patch clamp assays of an AtCNGC10-GFP fusion expressed in HEK293 cells measured significant cation currents. AtCNGC5 and AtCNGC10 are plasma membrane proteins. We postulate that AtCNGC10 traffics from the endoplasmic reticulum via the Golgi apparatus and associated vesicles to the plasma membrane. The presence of the cation channel, AtCNGC10, in root cap meristem cells, cell plate, and gravity-sensing columella cells, combined with the previously reported antisense phenotypes of decreased gravitropic and cell enlargement responses, suggest roles of AtCNGC10 in modulating cation balance required for root gravitropism, cell division and growth.

  11. A Framework for Monitoring Progress Using Summary Measures of Health.

    PubMed

    Madans, Jennifer H; Weeks, Julie D

    2016-10-01

    Initiatives designed to monitor health typically incorporate numerous specific measures of health and the health system to assess improvements, or lack thereof, for policy and program purposes. The addition of summary measures provides overarching information which is essential for determining whether the goals of such initiatives are met. Summary measures are identified that relate to the individual indicators but that also reflect movement in the various parts of the system. A hierarchical framework that is conceptually consistent and which utilizes a succinct number of summary measures incorporating indicators of functioning and participation is proposed. While a large set of individual indicators can be useful for monitoring progress, these individual indicators do not provide an overall evaluation of health, defined broadly, at the population level. A hierarchical framework consisting of summary measures is important for monitoring the success of health improvement initiatives. © The Author(s) 2016.

  12. Glutathione and fungal elicitor regulation of a plant defense gene promoter in electroporated protoplasts

    PubMed Central

    Dron, Michel; Clouse, Steven D.; Dixon, Richard A.; Lawton, Michael A.; Lamb, Christopher J.

    1988-01-01

    To investigate the mechanisms underlying activation of plant defenses against microbial attack we have studied elicitor regulation of a chimeric gene comprising the 5′ flanking region of a defense gene encoding the phytoalexin biosynthetic enzyme chalcone synthase fused to a bacterial chloramphenicol acetyltransferase gene. Glutathione or fungal elicitor caused a rapid, marked but transient expression of the chimeric gene electroporated into soybean protoplasts. The response closely resembled that of endogenous chalcone synthase genes in suspension cultured cells. Functional analysis of 5′ deletions suggests that promoter activity is determined by an elicitor-regulated activator located between the “TATA box” and nucleotide position -173 and an upstream silencer between -173 and -326. These cis-acting elements function in the transduction of the elicitation signal to initiate elaboration of an inducible defense response. Images PMID:16593981

  13. Differential compartmentation of sucrose and gentianose in the cytosol and vacuoles of storage root protoplasts from Gentiana Lutea L.

    PubMed

    Keller, F; Wiemken, A

    1982-12-01

    The storage roots of perennial Gentiana lutea L.plants contain several sugars. The predominant carbohydrate reserve is gentianose (β-D-glucopyranosyl-(1 → 6)-α-D-glucopyranosyl-(1 ↔ 2)-β-D-fructofuranoside). Vacuoles were isolated from root protoplasts and purified through a betaine density gradient. The yield was about 75%. Gentianose and gentiobiose were localized to 100% in the vacuoles, fructose and glucose to about 80%, and sucrose to only about 50%. Taking the volumes of the vacuolar and extravacuolar (cytosolic) compartments into account it is inferred that gentianose is located exclusively in the vacuoles, whilst sucrose is much more concentrated in the cytosol where it may play a role as a cryoprotectant. The concentration of fructose and glucose appeared to be similar on both sides of the tonoplast.

  14. Duplications created by transformation in Sordaria macrospora are not inactivated during meiosis.

    PubMed

    Le Chevanton, L; Leblon, G; Lebilcot, S

    1989-09-01

    We present here the first report of a transformation system developed for the filamentous fungus Sordaria macrospora. Protoplasts from a ura-5 strain were transformed using the cloned Sordaria gene at a frequency of 2 x 10(-5) transformants per viable protoplast (10 per microgram of DNA). Transformation occurred by integration of the donor sequences in the chromosomes of the recipient strain. In 71 cases out of 74, integration occurred outside the ura5 locus; frequently several (two to four) copies were found at a unique integration site. Using the advantage of the spore colour phenotype of the ura5-1 marker, we have shown that the transformed phenotype is stable through mitosis and meiosis in all transformants analysed. No methylation of the duplicated sequences could be observed during meiotic divisions in the transformants.

  15. Replication of plant RNA virus genomes in a cell-free extract of evacuolated plant protoplasts

    PubMed Central

    Komoda, Keisuke; Naito, Satoshi; Ishikawa, Masayuki

    2004-01-01

    The replication of eukaryotic positive-strand RNA virus genomes occurs through a complex process involving multiple viral and host proteins and intracellular membranes. Here we report a cell-free system that reproduces this process in vitro. This system uses a membrane-containing extract of uninfected plant protoplasts from which the vacuoles had been removed by Percoll gradient centrifugation. We demonstrate that the system supported translation, negative-strand RNA synthesis, genomic RNA replication, and subgenomic RNA transcription of tomato mosaic virus and two other plant positive-strand RNA viruses. The RNA synthesis, which depended on translation of the genomic RNA, produced virus-related RNA species similar to those that are generated in vivo. This system will aid in the elucidation of the mechanisms of genome replication in these viruses. PMID:14769932

  16. Apparent Inhibition of β-Fructosidase Secretion by Tunicamycin May Be Explained by Breakdown of the Unglycosylated Protein during Secretion 1

    PubMed Central

    Faye, Loïc; Chrispeels, Maarten J.

    1989-01-01

    Suspension-cultured carrot (Daucus carota) cells synthesize and secrete β-fructosidase, a glycoprotein with asparagine-linked glycans. Treatment of the cells with tunicamycin completely inhibits the apparent secretion of β-fructosidase as measured by the accumulation of the radioactive protein in the cell wall or the culture medium. In the past, such a result has been interpreted as an inhibition of secretion by tunicamycin, but we suggest another explanation based on the following results. In the presence of tunicamycin, unglycosylated β-fructosidase is synthesized and is associated with an endoplasmic-reticulum-rich microsomal fraction. Pulse-chase experiments show that the unglycosylated β-fructosidase does not remain in the cells and appears to be secreted in the same way as glycosylated β-fructosidase; however, no radioactive, unglycosylated β-fructosidase accumulates extracellularly (cell wall or medium). Protoplasts obtained from carrot cells secrete β-fructosidase protein and activity, and treatment of the protoplasts with tunicamycin results in the synthesis of unglycosylated β-fructosidase. In the presence of tunicamycin, there is no accumulation of β-fructosidase activity or unglycosylated β-fructosidase polypeptide in the protoplast incubation medium. These results are consistent with the interpretation that the glycans of β-fructosidase are necessary for its stability, and that in these suspension-cultured cells, the unglycosylated enzyme is degraded during the last stage(s) of secretion, or immediately after its arrival in the wall. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:16666631

  17. Involvement of Ethylene in Stress-Induced Expression of the TLC1.1 Retrotransposon from Lycopersicon chilense Dun.1[w

    PubMed Central

    Tapia, Gerardo; Verdugo, Isabel; Yañez, Mónica; Ahumada, Iván; Theoduloz, Cristina; Cordero, Cecilia; Poblete, Fernando; González, Enrique; Ruiz-Lara, Simón

    2005-01-01

    The TLC1 family is one of the four families of long terminal repeat (LTR) retrotransposons identified in the genome of Lycopersicon chilense. Here, we show that this family of retroelements is transcriptionally active and its expression is induced in response to diverse stress conditions such as wounding, protoplast preparation, and high salt concentrations. Several stress-associated signaling molecules, including ethylene, methyl jasmonate, salicylic acid, and 2,4-dichlorophenoxyacetic acid, are capable of inducing TLC1 family expression in vivo. A representative of this family, named TLC1.1, was isolated from a genomic library from L. chilense. Transient expression assays in leaf protoplasts and stably transformed tobacco (Nicotiana tabacum) plants demonstrate that the U3 domain of the 5′-LTR region of this element can drive stress-induced transcriptional activation of the β-glucuronidase reporter gene. Two 57-bp tandem repeated sequences are found in this region, including an 8-bp motif, ATTTCAAA, previously identified as an ethylene-responsive element box in the promoter region of ethylene-induced genes. Expression analysis of wild-type LTR and single and double ethylene-responsive element box mutants fused to the β-glucuronidase gene shows that these elements are required for ethylene-responsive gene expression in protoplasts and transgenic plants. We suggest that ethylene-dependent signaling is the main signaling pathway involved in the regulation of the expression of the TLC1.1 element from L. chilense. PMID:16040666

  18. Apparent inhibition of. beta. -fructosidase secretion by tunicamycin may be explained by breakdown of the unglycosylated protein during secretion. [Daucus carota

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Faye, L.; Chrispeels, M.J.

    1989-03-01

    Suspension-cultured carrot (Daucus carota) cells synthesize and secrete {beta}-fructosidase, a glycoprotein with asparagine-linked glycans. Treatment of the cells with tunicamycin completely inhibits the apparent secretion of {beta}-fructosidase as measured by the accumulation of the {sup 35}S-labelled protein in the cell wall or the culture medium. In the past, such a result has been interpreted as an inhibition of secretion by tunicamycin, but we suggest another explanation based on the following results. In the presence of tunicamycin, unglycosylated {beta}-fructosidase is synthesized and is associated with an endoplasmic-reticulum-rich microsomal fraction. Pulse-chase experiments show that the unglycosylated {beta}-fructosidase does not remain in themore » cells and appears to be secreted in the same way as glycosylated {beta}-fructosidase; however, no radioactive, unglycosylated {beta}-fructosidase accumulates extracellularly (cell wall or medium). Protoplasts obtained from carrot cells secrete {beta}-fructosidase protein and activity, and treatment of the protoplasts with tunicamycin results in the synthesis of unglycosylated {beta}-fructosidase. In the presence of tunicamycin, there is no accumulation of {beta}-fructosidase activity or unglycosylated {beta}-fructosidase polypeptide in the protoplast incubation medium. These results are consistent with the interpretation that the glycans of {beta}-fructosidase are necessary for its stability, and that in these suspension-cultured cells, the unglycosylated enzyme is degraded during the last stage(s) of secretion, or immediately after its arrival in the wall.« less

  19. Introduction of transformed chloroplasts from tobacco into petunia by asymmetric cell fusion.

    PubMed

    Sigeno, Asako; Hayashi, Sugane; Terachi, Toru; Yamagishi, Hiroshi

    2009-11-01

    Plastid engineering technique has been established only in Nicotiana tabacum, and the widespread application is severely limited so far. In order to exploit a method to transfer the genetically transformed plastomes already obtained in tobacco into other plant species, somatic cell fusion was conducted between a plastome transformant of tobacco and a cultivar of petunia (Petunia hybrida). A tobacco strain whose plastids had been transformed with aadA (a streptomycin/spectinomycin adenylyltransferase gene) and mdar [a gene for monodehydroascorbate reductase (MDAR)] and a petunia variety, 'Telstar', were used as cell fusion partners. An efficient regeneration system from the protoplasts of both the parents, and effectiveness of selection for the aadA gene with spectinomycin were established before the cell fusion. In addition, the influence of UV irradiation on the callus development from the protoplasts and shoot regeneration of tobacco was investigated. Protoplasts were cultured after cell fusion treatment with polyethylene glycol, and asymmetric somatic cybrids were selected using the aadA gene as a marker. Although many shoots of tobacco that had escaped the UV irradiation regenerated, several shoots possessing the morphology of petunia and the resistance to spectinomycin were obtained. Molecular analyses of the petunia type regenerants demonstrated that they had the nuclear and mitochondrial genomes derived from petunia besides the chloroplasts of tobacco transformed with aadA and mdar. Furthermore, it was ascertained that mdar was transcribed in the somatic cybrids. The results indicate the success in intergeneric transfer of transformed plastids of tobacco into petunia.

  20. Introgression of Swertia mussotii gene into Bupleurum scorzonerifolium via somatic hybridization

    PubMed Central

    2011-01-01

    Background The wild herb Swertia mussotii is a source of the anti-hepatitis compounds swertiamarin, mangiferin and gentiopicroside. Its over-exploitation has raised the priority of producing these compounds heterologously. Somatic hybridization represents a novel approach for introgressing Swertia mussotii genes into a less endangered species. Results Protoplasts derived from calli of Bupleurum scorzonerifolium and S. mussotii were fused to produce 194 putative hybrid cell lines, of which three (all derived from fusions where the S. mussotii protoplasts were pre-treated for 30 s with UV light) later differentiated into green plants. The hybridity of the calli was confirmed by a combination of isozyme, RAPD and chromosomal analysis. The hybrid calli genomes were predominantly B. scorzonerifolium. GISH analysis of mitotic chromosomes confirmed that the irradiation of donor protoplasts increased the frequency of chromosome elimination and fragmentation. RFLP analysis of organellar DNA revealed that mitochondrial and chloroplast DNA of both parents coexisted and recombined in some hybrid cell lines. Some of the hybrid calli contained SmG10H from donor, and produced swertiamarin, mangiferin and certain volatile compounds characteristic of S. mussotii. The expression of SmG10H (geraniol 10-hydroxylase) was associated with the heterologous accumulation of swertiamarin. Conclusions Somatic hybrids between B. scorzonerifolium and S. mussotii were obtained, hybrids selected all contained introgressed nuclear and cytoplasmic DNA from S. mussotii; and some produced more mangiferin than the donor itself. The introgression of SmG10H was necessary for the accumulation of swertiamarin. PMID:21513581

  1. 76 FR 57012 - Progress Reports Rules Revision

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-15

    ... Reports Rules Revision AGENCY: Bureau of Prisons, Justice. ACTION: Proposed rule. SUMMARY: In this... progress reports: Transfer reports and triennial reports. DATES: Comments are due by November 14, 2011... progress reports: Transfer reports and triennial reports. Section 524.41, entitled ``Types of progress...

  2. Crop improvement and conservation through tissue culture techniques

    USDA-ARS?s Scientific Manuscript database

    Crop improvement through classic breeding and/or genetic engineering methods is possible in the majority of cultivated crops. However, gene manipulations, chromosome duplication, protoplast fusion, bioassays, interspecific cross recovery involve tissue culture techniques. For vegetatively propagated...

  3. Highly Efficient Electroporation-mediated Transformation into Edible Mushroom Flammulina velutipes

    PubMed Central

    Kim, Jong Kun; Park, Young Jin; Kong, Won Sik

    2010-01-01

    In this study, we developed an efficient electroporation-mediated transformation system featuring Flammulina velutipes. The flammutoxin (ftx) gene of F. velutipes was isolated by reverse transcription-PCR. pFTXHg plasmid was constructed using the partial ftx gene (410 bp) along with the hygromycin B phosphotransferase gene (hygB) downstream of the glyceraldehydes-3-phosphate dehydrogenase (gpd) promoter. The plasmid was transformed into protoplasts of monokaryotic strain 4019-20 of F. velutipes by electroporation. High transformation efficiency was obtained with an electric-pulse of 1.25 kV/cm by using 177 transformants/µg of DNA in 1 × 107 protoplasts. PCR and Southern blot hybridization indicated that a single copy of the plasmid DNA was inserted at different locations in the F. velutipes genome by non-homologous recombination. Therefore, this transformation system could be used as a useful tool for gene function analysis of F. velutipes. PMID:23956676

  4. Highly Efficient Electroporation-mediated Transformation into Edible Mushroom Flammulina velutipes.

    PubMed

    Kim, Jong Kun; Park, Young Jin; Kong, Won Sik; Kang, Hee Wan

    2010-12-01

    In this study, we developed an efficient electroporation-mediated transformation system featuring Flammulina velutipes. The flammutoxin (ftx) gene of F. velutipes was isolated by reverse transcription-PCR. pFTXHg plasmid was constructed using the partial ftx gene (410 bp) along with the hygromycin B phosphotransferase gene (hygB) downstream of the glyceraldehydes-3-phosphate dehydrogenase (gpd) promoter. The plasmid was transformed into protoplasts of monokaryotic strain 4019-20 of F. velutipes by electroporation. High transformation efficiency was obtained with an electric-pulse of 1.25 kV/cm by using 177 transformants/µg of DNA in 1 × 10(7) protoplasts. PCR and Southern blot hybridization indicated that a single copy of the plasmid DNA was inserted at different locations in the F. velutipes genome by non-homologous recombination. Therefore, this transformation system could be used as a useful tool for gene function analysis of F. velutipes.

  5. ( sup 14 C)-Sucrose uptake by guard cell protoplasts of pisum sativum, argenteum mutant

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rohrig, K.; Raschke, K.

    1991-05-01

    Guard cells rely on import for their supply with reduced carbon. The authors tested by silicone oil centrifugation the ability of guard cell protoplasts to accumulated ({sup 14}C)-sucrose. Uptake rates were corrected after measurement of {sup 14}C-sorbitol and {sup 3}H{sub 2}O spaces. Sucrose uptake followed biphasic kinetics, with a high-affinity component below 1 mM external sucrose (apparent K{sub m} 0.8 mM at 25C) and a low-affinity nonsaturable component above. Uptake depended on pH (optimum at pH 5.0). Variations in the concentrations of external KCl, CCCP, and valinomycin indicated that about one-half of the sucrose uptake rate could be related tomore » an electrochemical gradient across the plasmalemma. Total uptake rates measured at 5 mM external sucrose seem to be sufficient to replenish emptied plastids with starch within a few hours.« less

  6. Genetic transformation of the plant pathogens Phytophthora capsici and Phytophthora parasitica.

    PubMed Central

    Bailey, A M; Mena, G L; Herrera-Estrella, L

    1991-01-01

    Phytophthora capsici and P.parasitica were transformed to hygromycin B resistance using plasmids pCM54 and pHL1, which contain the bacterial hygromycin B phosphotransferase gene (hph) fused to promoter elements of the Ustilago maydis heat shock hsp70 gene. Enzymes Driselase and Novozyme 234 were used to generate protoplasts which were then transformed following exposure to plasmid DNA and polyethylene glycol 6000. Transformation frequencies of over 500 transformants per micrograms of DNA per 1 x 10(6) protoplasts were obtained. Plasmid pCM54 appears to be transmitted in Phytophthora spp. as an extra-chromosomal element through replication, as shown by Southern blot hybridization and by the loss of plasmid methylation. In addition, transformed strains retained their capacity of infecting Serrano pepper seedlings and Mc. Intosh apple fruits, the host plants for P.capsici and P.parasitica, respectively. Images PMID:1651483

  7. Induced parasexual processes in Claviceps sp. strain SD58.

    PubMed Central

    Brauer, K L; Robbers, J E

    1987-01-01

    A homokaryotic, clavine alkaloid-producing strain of ergot, Claviceps sp. strain SD 58, was used in an attempt to demonstrate parasexuality. Genetically marked auxotrophic strains were produced by mutation with N-methyl-N'-nitro-N-nitrosoguanidine. Protoplast fusion of pairs of unlike doubly auxotrophic strains and isolation of stable prototrophic fusion products were carried out. By growth of the fusion products on complete medium, selective pressure for prototrophy was removed and auxotrophic segregants were allowed to form. Analysis of these and recovery of segregants with nonleaky, non-parent-type combinations of auxotrophic characteristics has provided strong evidence that a parasexual cycle can function in Claviceps sp. strain SD 58. Preliminary work suggests that the genetics of ergot might be studied by mitotic analysis and that protoplast fusion and selection procedures might be useful for the enhancement of favorable characteristics in Claviceps strains. PMID:3827250

  8. Construction and evaluation of an exopolysaccharide-producing engineered bacterial strain by protoplast fusion for microbial enhanced oil recovery.

    PubMed

    Sun, Shanshan; Luo, Yijing; Cao, Siyuan; Li, Wenhong; Zhang, Zhongzhi; Jiang, Lingxi; Dong, Hanping; Yu, Li; Wu, Wei-Min

    2013-09-01

    Enterobacter cloacae strain JD, which produces water-insoluble biopolymers at optimal temperature of 30°C, and a thermophilic Geobacillus strain were used to construct an engineered strain for exopolysaccharide production at high temperatures by protoplast fusion. The obtained fusant strain ZR3 produced exopolysaccharides at up to 45°C with optimal growth temperature at 35°C. The fusant produced exopolysaccharides of approximately 7.5 g/L or more at pH between 7.0 and 9.0. The feasibility of the enhancement of crude oil recovery with the fusant was tested in a sand-packed column at 40°C. The results demonstrated that bioaugmentation of the fusant was promising approach for MEOR. Mass growth of the fusant was confirmed in fermentor tests. Copyright © 2013 Elsevier Ltd. All rights reserved.

  9. Somatic hybridization of sexually incompatible petunias: Petunia parodii, Petunia parviflora.

    PubMed

    Power, J B; Berry, S F; Chapman, J V; Cocking, E C

    1980-01-01

    Somatic hybrid plants were regenerated following the fusion of leaf mesophyll protoplasts of P. parodii with those isolated from a nuclear-albino mutant of P. parviflora. Attempts at sexual hybridization of these two species repeatedly failed thus confirming their previously established cross-incompatibility. Selection of somatic hybrid plants was possible since protoplasts of P. parodii would not develop beyond the cell colony stage, whilst those of the somatic hybrid and albino P. parviflora produced calluses. Green somatic hybrid calluses were visible against a background of albino cells/calluses, and upon transfer to regeneration media gave rise to shoots. Shoots and the resultant flowering plants were confirmed as somatic hybrids based on their growth habit, floral pigmentation and morphology, leaf hair structure, chromosome number and Fraction 1 protein profiles. The relevance of such hybrid material for the development of new, and extensively modified cultivars, is discussed.

  10. Replication of alfalfa mosaic virus RNA 3 with movement and coat protein genes replaced by corresponding genes of Prunus necrotic ringspot ilarvirus.

    PubMed

    Sánchez-Navarro, J A; Reusken, C B; Bol, J F; Pallás, V

    1997-12-01

    Alfalfa mosaic virus (AMV) and Prunus necrotic ringspot virus (PNRSV) are tripartite positive-strand RNA plant viruses that encode functionally similar translation products. Although the two viruses are phylogenetically closely related, they infect a very different range of natural hosts. The coat protein (CP) gene, the movement protein (MP) gene or both genes in AMV RNA 3 were replaced by the corresponding genes of PNRSV. The chimeric viruses were tested for heterologous encapsidation, replication in protoplasts from plants transformed with AMV replicase genes P1 and P2 (P12 plants) and for cell-to-cell transport in P12 plants. The chimeric viruses exhibited basic competence for encapsidation and replication in P12 protoplasts and for a low level of cell-to-cell movement in P12 plants. The potential involvement of the MP gene in determining host specificity in ilarviruses is discussed.

  11. 78 FR 60755 - Hazardous Materials: Enhanced Enforcement Procedures-Resumption of Transportation

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-02

    .... Summary of MAP-21 and Final Rule V. Summary Review of Amendments VI. Regulatory Analyses and Notices A.... Executive Summary On July 6, 2012, the President signed the Moving Ahead for Progress in the 21st Century Act, or the MAP-21, which included the Hazardous Materials Transportation Safety Improvement Act of...

  12. The nature and origin of nucleus-like intracellular inclusions in Paleoproterozoic eukaryote microfossils.

    PubMed

    Pang, K; Tang, Q; Schiffbauer, J D; Yao, J; Yuan, X; Wan, B; Chen, L; Ou, Z; Xiao, S

    2013-11-01

    The well-known debate on the nature and origin of intracellular inclusions (ICIs) in silicified microfossils from the early Neoproterozoic Bitter Springs Formation has recently been revived by reports of possible fossilized nuclei in phosphatized animal embryo-like fossils from the Ediacaran Doushantuo Formation of South China. The revisitation of this discussion prompted a critical and comprehensive investigation of ICIs in some of the oldest indisputable eukaryote microfossils-the ornamented acritarchs Dictyosphaera delicata and Shuiyousphaeridium macroreticulatum from the Paleoproterozoic Ruyang Group of North China-using a suite of characterization approaches: scanning electron microscopy (SEM), transmission electron microscopy (TEM), and focused ion beam scanning electron microscopy (FIB-SEM). Although the Ruyang acritarchs must have had nuclei when alive, our data suggest that their ICIs represent neither fossilized nuclei nor taphonomically condensed cytoplasm. We instead propose that these ICIs likely represent biologically contracted and consolidated eukaryotic protoplasts (the combination of the nucleus, surrounding cytoplasm, and plasma membrane). As opposed to degradational contraction of prokaryotic cells within a mucoidal sheath-a model proposed to explain the Bitter Springs ICIs-our model implies that protoplast condensation in the Ruyang acritarchs was an in vivo biologically programmed response to adverse conditions in preparation for encystment. While the discovery of bona fide nuclei in Paleoproterozoic acritarchs would be a substantial landmark in our understanding of eukaryote evolution, the various processes (such as degradational and biological condensation of protoplasts) capable of producing nuclei-mimicking structures require that interpretation of ICIs as fossilized nuclei be based on comprehensive investigations. © 2013 John Wiley & Sons Ltd.

  13. Optimized Methods for the Isolation of Arabidopsis Female Central Cells and Their Nuclei

    PubMed Central

    Park, Kyunghyuk; Frost, Jennifer M.; Adair, Adam James; Kim, Dong Min; Yun, Hyein; Brooks, Janie S.; Fischer, Robert L.; Choi, Yeonhee

    2016-01-01

    The Arabidopsis female gametophyte contains seven cells with eight haploid nuclei buried within layers of sporophytic tissue. Following double fertilization, the egg and central cells of the gametophyte develop into the embryo and endosperm of the seed, respectively. The epigenetic status of the central cell has long presented an enigma due both to its inaccessibility, and the fascinating epigenome of the endosperm, thought to have been inherited from the central cell following activity of the DEMETER demethylase enzyme, prior to fertilization. Here, we present for the first time, a method to isolate pure populations of Arabidopsis central cell nuclei. Utilizing a protocol designed to isolate leaf mesophyll protoplasts, we systematically optimized each step in order to efficiently separate central cells from the female gametophyte. We use initial manual pistil dissection followed by the derivation of central cell protoplasts, during which process the central cell emerges from the micropylar pole of the embryo sac. Then, we use a modified version of the Isolation of Nuclei TAgged in specific Cell Types (INTACT) protocol to purify central cell nuclei, resulting in a purity of 75–90% and a yield sufficient to undertake downstream molecular analyses. We find that the process is highly dependent on the health of the original plant tissue used, and the efficiency of protoplasting solution infiltration into the gametophyte. By isolating pure central cell populations, we have enabled elucidation of the physiology of this rare cell type, which in the future will provide novel insights into Arabidopsis reproduction. PMID:27788573

  14. Multiple Xanthomonas euvesicatoria Type III Effectors Inhibit flg22-Triggered Immunity.

    PubMed

    Popov, Georgy; Fraiture, Malou; Brunner, Frederic; Sessa, Guido

    2016-08-01

    Xanthomonas euvesicatoria is the causal agent of bacterial spot disease in pepper and tomato. X. euvesicatoria bacteria interfere with plant cellular processes by injecting effector proteins into host cells through the type III secretion (T3S) system. About 35 T3S effectors have been identified in X. euvesicatoria 85-10, and a few of them were implicated in suppression of pattern-triggered immunity (PTI). We used an Arabidopsis thaliana pathogen-free protoplast-based assay to identify X. euvesicatoria 85-10 effectors that interfere with PTI signaling induced by the bacterial peptide flg22. Of 33 tested effectors, 17 inhibited activation of a PTI-inducible promoter. Among them, nine effectors also interfered with activation of an abscisic acid-inducible promoter. However, effectors that inhibited flg22-induced signaling did not affect phosphorylation of mitogen-activated protein (MAP) kinases acting downstream of flg22 perception. Further investigation of selected effectors revealed that XopAJ, XopE2, and XopF2 inhibited activation of a PTI-inducible promoter by the bacterial peptide elf18 in Arabidopsis protoplasts and by flg22 in tomato protoplasts. The effectors XopF2, XopE2, XopAP, XopAE, XopH, and XopAJ inhibited flg22-induced callose deposition in planta and enhanced disease symptoms caused by attenuated Pseudomonas syringae bacteria. Finally, selected effectors were found to localize to various plant subcellular compartments. These results indicate that X. euvesicatoria bacteria utilize multiple T3S effectors to suppress flg22-induced signaling acting downstream or in parallel to MAP kinase cascades and suggest they act through different molecular mechanisms.

  15. Laboratory Course on "Streptomyces" Genetics and Secondary Metabolism

    ERIC Educational Resources Information Center

    Siitonen, Vilja; Räty, Kaj; Metsä-Ketelä, Mikko

    2016-01-01

    The "'Streptomyces' genetics and secondary metabolism" laboratory course gives an introduction to the versatile soil dwelling Gram-positive bacteria "Streptomyces" and their secondary metabolism. The course combines genetic modification of "Streptomyces"; growing of the strain and protoplast preparation, plasmid…

  16. Gypsy moth larval defense mechanisms against pathogenic microorganisms

    Treesearch

    Kathleen S. Shields; Tariq M. Butt

    1991-01-01

    We investigated the response of gypsy moth, Lymantria dispar, larval hemocytes to L. dispar nuclear polyhedrosis virus (LdMNPV) administered per os and by injection, and to injected hyphal bodies and natural protoplasts of some entomopathogenic, entomophthoralean fungi.

  17. Transmembrane potential measurements on plant cells using the voltage-sensitive dye ANNINE-6.

    PubMed

    Flickinger, Bianca; Berghöfer, Thomas; Hohenberger, Petra; Eing, Christian; Frey, Wolfgang

    2010-11-01

    The charging of the plasma membrane is a necessary condition for the generation of an electric-field-induced permeability increase of the plasmalemma, which is usually explained by the creation and the growth of aqueous pores. For cells suspended in physiological buffers, the time domain of membrane charging is in the submicrosecond range. Systematic measurements using Nicotiana tabacum L. cv. Bright Yellow 2 (BY-2) protoplasts stained with the fast voltage-sensitive fluorescence dye ANNINE-6 have been performed using a pulsed laser fluorescence microscopy setup with a time resolution of 5 ns. A clear saturation of the membrane voltage could be measured, caused by a strong membrane permeability increase, commonly explained by enhanced pore formation, which prevents further membrane charging by external electric field exposure. The field strength dependence of the protoplast's transmembrane potential V (M) shows strong asymmetric saturation characteristics due to the high resting potential of the plants plasmalemma. At the pole of the hyperpolarized hemisphere of the cell, saturation starts at an external field strength of 0.3 kV/cm, resulting in a measured transmembrane voltage shift of ∆V(M) = -150 mV, while on the cathodic (depolarized) cell pole, the threshold for enhanced pore formation is reached at a field strength of approximately 1.0 kV/cm and ∆V(M) = 450 mV, respectively. From this asymmetry of the measured maximum membrane voltage shifts, the resting potential of BY-2 protoplasts at the given experimental conditions can be determined to V(R) = -150 mV. Consequently, a strong membrane permeability increase occurs when the membrane voltage diverges |V(M)| = 300 mV from the resting potential of the protoplast. The largest membrane voltage change at a given external electric field occurs at the cell poles. The azimuthal dependence of the transmembrane potential, measured in angular intervals of 10° along the circumference of the cell, shows a flattening and a slight decrease at higher fields at the pole region due to enhanced pore formation. Additionally, at the hyperpolarized cell pole, a polarization reversal could be observed at an external field range around 1.0 kV/cm. This behavior might be attributed to a fast charge transfer through the membrane at the hyperpolarized pole, e.g., by voltage-gated channels.

  18. Altered gene expression changes in Arabidopsis leaf tissues and protoplasts in response to Plum pox virus infection

    PubMed Central

    Babu, Mohan; Griffiths, Jonathan S; Huang, Tyng-Shyan; Wang, Aiming

    2008-01-01

    Background Virus infection induces the activation and suppression of global gene expression in the host. Profiling gene expression changes in the host may provide insights into the molecular mechanisms that underlie host physiological and phenotypic responses to virus infection. In this study, the Arabidopsis Affymetrix ATH1 array was used to assess global gene expression changes in Arabidopsis thaliana plants infected with Plum pox virus (PPV). To identify early genes in response to PPV infection, an Arabidopsis synchronized single-cell transformation system was developed. Arabidopsis protoplasts were transfected with a PPV infectious clone and global gene expression changes in the transfected protoplasts were profiled. Results Microarray analysis of PPV-infected Arabidopsis leaf tissues identified 2013 and 1457 genes that were significantly (Q ≤ 0.05) up- (≥ 2.5 fold) and downregulated (≤ -2.5 fold), respectively. Genes associated with soluble sugar, starch and amino acid, intracellular membrane/membrane-bound organelles, chloroplast, and protein fate were upregulated, while genes related to development/storage proteins, protein synthesis and translation, and cell wall-associated components were downregulated. These gene expression changes were associated with PPV infection and symptom development. Further transcriptional profiling of protoplasts transfected with a PPV infectious clone revealed the upregulation of defence and cellular signalling genes as early as 6 hours post transfection. A cross sequence comparison analysis of genes differentially regulated by PPV-infected Arabidopsis leaves against uniEST sequences derived from PPV-infected leaves of Prunus persica, a natural host of PPV, identified orthologs related to defence, metabolism and protein synthesis. The cross comparison of genes differentially regulated by PPV infection and by the infections of other positive sense RNA viruses revealed a common set of 416 genes. These identified genes, particularly the early responsive genes, may be critical in virus infection. Conclusion Gene expression changes in PPV-infected Arabidopsis are the molecular basis of stress and defence-like responses, PPV pathogenesis and symptom development. The differentially regulated genes, particularly the early responsive genes, and a common set of genes regulated by infections of PPV and other positive sense RNA viruses identified in this study are candidates suitable for further functional characterization to shed lights on molecular virus-host interactions. PMID:18613973

  19. Geological Survey research 1981

    USGS Publications Warehouse

    ,

    1982-01-01

    This U.S. Geological Survey activities report includes a summary of 1981 fiscal year scientific and economic results accompanied by a list of geologic, hydrologic, and cartographic investigations in progress. The summary of results includes: (1) Mineral, (2) Water resources, (3) Engineering geology and hydrology, (4) Regional geology, (5) Principles and processes, (6) Laboratory and field methods, (7) Topographic surveys and mapping, (8) Management of resources on public lands, (9) Land information and analysis, and (10) Investigations in other countries. Also included are lists of investigations in progress.

  20. Contracts for field projects and supporting research on enhanced oil recovery. Progress review number 83, quarter ending June 30, 1995

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    NONE

    Summaries of 41 research projects on enhanced recovery are presented under the following sections: (1) chemical flooding; (2) gas displacement; (3) thermal recovery; (4) geoscience technology; (5) resource assessment technology; and (6) reservoir classes. Each presentation gives the title of the project, contract number, research facility, contract date, expected completion data, amount of the award, principal investigator, and DOE program manager, and describes the objectives of the project and a summary of the technical progress.

  1. Summary Tables | Cancer Trends Progress Report

    Cancer.gov

    The Cancer Trends Progress Report, first issued in 2001, summarizes our nation's advances against cancer in relation to Healthy People targets set forth by the Department of Health and Human Services.

  2. Prevention Summary Tables | Cancer Trends Progress Report

    Cancer.gov

    The Cancer Trends Progress Report, first issued in 2001, summarizes our nation's advances against cancer in relation to Healthy People targets set forth by the Department of Health and Human Services.

  3. Treatment Summary Tables | Cancer Trends Progress Report

    Cancer.gov

    The Cancer Trends Progress Report, first issued in 2001, summarizes our nation's advances against cancer in relation to Healthy People targets set forth by the Department of Health and Human Services.

  4. 48 CFR 2452.242-71 - Contract management system.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ..., concise summary of technical progress made and the costs incurred for each task during the reporting... technical progress made for each task during the reporting period; and (B) Identifies problems, or potential... and progress reporting as described herein. (b) The contract management system shall consist of two...

  5. Diet - Prevention Summary Table | Cancer Trends Progress Report

    Cancer.gov

    The Cancer Trends Progress Report, first issued in 2001, summarizes our nation's advances against cancer in relation to Healthy People targets set forth by the Department of Health and Human Services.

  6. Tobacco Use - Prevention Summary Table | Cancer Trends Progress Report

    Cancer.gov

    The Cancer Trends Progress Report, first issued in 2001, summarizes our nation's advances against cancer in relation to Healthy People targets set forth by the Department of Health and Human Services.

  7. Chemical Exposures - Prevention Summary Table | Cancer Trends Progress Report

    Cancer.gov

    The Cancer Trends Progress Report, first issued in 2001, summarizes our nation's advances against cancer in relation to Healthy People targets set forth by the Department of Health and Human Services.

  8. Secondhand Smoke - Prevention Summary Table | Cancer Trends Progress Report

    Cancer.gov

    The Cancer Trends Progress Report, first issued in 2001, summarizes our nation's advances against cancer in relation to Healthy People targets set forth by the Department of Health and Human Services.

  9. HPV Immunization - Prevention Summary Table | Cancer Trends Progress Report

    Cancer.gov

    The Cancer Trends Progress Report, first issued in 2001, summarizes our nation's advances against cancer in relation to Healthy People targets set forth by the Department of Health and Human Services.

  10. Life After Cancer Summary Tables | Cancer Trends Progress Report

    Cancer.gov

    The Cancer Trends Progress Report, first issued in 2001, summarizes our nation's advances against cancer in relation to Healthy People targets set forth by the Department of Health and Human Services.

  11. Smoking Cessation - Prevention Summary Table | Cancer Trends Progress Report

    Cancer.gov

    The Cancer Trends Progress Report, first issued in 2001, summarizes our nation's advances against cancer in relation to Healthy People targets set forth by the Department of Health and Human Services.

  12. Enhanced Transgene Expression in Sugarcane by Co-Expression of Virus-Encoded RNA Silencing Suppressors

    PubMed Central

    Park, Jong-Won; Beyene, Getu; Buenrostro-Nava, Marco T.; Molina, Joe; Wang, Xiaofeng; Ciomperlik, Jessica J.; Manabayeva, Shuga A.; Alvarado, Veria Y.; Rathore, Keerti S.; Scholthof, Herman B.; Mirkov, T. Erik

    2013-01-01

    Post-transcriptional gene silencing is commonly observed in polyploid species and often poses a major limitation to plant improvement via biotechnology. Five plant viral suppressors of RNA silencing were evaluated for their ability to counteract gene silencing and enhance the expression of the Enhanced Yellow Fluorescent Protein (EYFP) or the β-glucuronidase (GUS) reporter gene in sugarcane, a major sugar and biomass producing polyploid. Functionality of these suppressors was first verified in Nicotiana benthamiana and onion epidermal cells, and later tested by transient expression in sugarcane young leaf segments and protoplasts. In young leaf segments co-expressing a suppressor, EYFP reached its maximum expression at 48–96 h post-DNA introduction and maintained its peak expression for a longer time compared with that in the absence of a suppressor. Among the five suppressors, Tomato bushy stunt virus-encoded P19 and Barley stripe mosaic virus-encoded γb were the most efficient. Co-expression with P19 and γb enhanced EYFP expression 4.6-fold and 3.6-fold in young leaf segments, and GUS activity 2.3-fold and 2.4-fold in protoplasts compared with those in the absence of a suppressor, respectively. In transgenic sugarcane, co-expression of GUS and P19 suppressor showed the highest accumulation of GUS levels with an average of 2.7-fold more than when GUS was expressed alone, with no detrimental phenotypic effects. The two established transient expression assays, based on young leaf segments and protoplasts, and confirmed by stable transgene expression, offer a rapid versatile system to verify the efficiency of RNA silencing suppressors that proved to be valuable in enhancing and stabilizing transgene expression in sugarcane. PMID:23799071

  13. Effect of 1-aminocyclopropane-1-carboxylic acid on the production of ethylene in senescing flowers of Ipomoea tricolor Cav

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Konze, J.R.; Jones, J.F.; Boller, T.

    1980-10-01

    Application of 1-aminocyclopropane-1-carboxylic acid (ACC) to rib segments excised from flowers of Ipomoea tricolor Cav. resulted in the formation of C/sub 2/H/sub 4/ in greater quantities than produced under natural conditions. The ability of ACC to enhance C/sub 2/H/sub 4/ production was independent of the physiological age of the tissue and its capacity to synthesize C/sub 2/H/sub 4/ without applied ACC. When ACC was fed to rib segments that had been treated with (/sup 14/C)methionine, incorporation of radioactivity into C/sub 2/H/sub 4/ was reduced by 80%. Aminoethoxyvinylglycine and aminooxyacetic acid inhibited C/sub 2/H/sub 4/ production in rib segments of I.more » tricolor but had no effect on ACC-enhanced C/sub 2/H/sub 4/ production. Protoplasts obtained from flower tissue of I. tricolor did not form C/sub 2/H/sub 4/, even when incubated with methionine or selenomethionine. They produced C/sub 2/H/sub 4/ upon incubation with ACC, however. ACC-dependent C/sub 2/H/sub 4/ production in protoplasts was inhibited by n-propyl gallate, AgCl, CoCl/sub 2/, KCN, Na/sub 2/S, and NaN/sub 3/. ACC-dependent C/sub 2/H/sub 4/ synthesis in rib segments and protoplasts was dependent on O/sub 2/, the K/sub m/ for O/sub 2/ being 1.0 to 1.4% (v/v). These results confirm the following pathway for C/sub 2/H/sub 4/ biosynthesis in I. tricolor: methionine (selenomethionine) ..-->..S-adenosylmethionine (selenoadenosylmethionine) ..-->.. ACC ..-->.. C/sub 2/H/sub 4/.« less

  14. Interspecific somatic hybrid plants between eggplant (Solanum melongena) and Solanum torvum.

    PubMed

    Guri, A; Sink, K C

    1988-10-01

    Mesophyll protoplasts of eggplant (cv Black Beauty) and of Solanum torvum (both 2n=2x=24) were fused using a modification of the Menczel and Wolfe PEG/DMSO procedure. Protoplasts post-fusion were plated at 1 × 10(5)/ml in modified KM medium, which inhibited division of S. torvum protoplasts. One week prior to shoot regeneration, ten individual calluses had a unique light-green background and were verified as cell hybrids by the presence of the dimer isozyme patterns for phosphoglucoisomerase (PGI) and glutamate oxaloacetate transaminase (GOT). Hybridity was also confirmed at the plant stage by DNA-DNA hybridization to a pea 45S ribosomal RNA gene probe. The ten somatic hybrid plants were established in the greenhouse and exhibited intermediate morphological characteristics such as leaf size and shape, flower size, shape, color and plant stature. Their chromosome number ranged from 46-48 (expected 2n=4x=48) and pollen viability was 5%-70%. In vitro shoots taken from the ten hybrid plants exhibited resistance to a verticillium wilt extract. Total DNA from the ten hybrids was restricted and hybridized with a 5.9 kb Oenothera chloroplast cytochrome f gene probe, a 2.4 kb EcoRI clone encoding mitochondrial cytochrome oxidase subunit II from maize and a 22.1 kb Sal I mitochondrial clone from Nicotiana sylvestris. Southern blot hybridization patterns showed that eight of ten somatic hybrids contained the eggplant cpDNA, while two plants contained the cpDNA hybridization patterns of both parents. The mtDNA analysis revealed the presence of novel bands, loss of some specific parental bands and mixture of specific bands from both parents in the restriction hybridization profiles of the hybrids.

  15. Efficient callus formation and plant regeneration of goosegrass [Eleusine indica (L.) Gaertn.].

    PubMed

    Yemets, A I; Klimkina, L A; Tarassenko, L V; Blume, Y B

    2003-02-01

    Efficient methods in totipotent callus formation, cell suspension culture establishment and whole-plant regeneration have been developed for the goosegrass [ Eleusine indica (L.) Gaertn.] and its dinitroaniline-resistant biotypes. The optimum medium for inducing morphogenic calli consisted of N6 basal salts and B5 vitamins supplemented with 1-2 mg l(-1) 2,4-dichlorophenoxyacetic acid (2,4-D), 2 mg l(-1) glycine, 100 mg l(-1) asparagine, 100 mg l(-1) casein hydrolysate, 30 g l(-1) sucrose and 0.6% agar, pH 5.7. The presence of organogenic and embryogenic structures in these calli was histologically documented. Cell suspension cultures derived from young calli were established in a liquid medium with the same composition. Morphogenic structures of direct shoots and somatic embryos were grown into rooted plantlets on medium containing MS basal salts, B5 vitamins, 1 mg l(-1) kinetin (Kn) and 0.1 mg l(-1) indole-3-acetic acid (IAA), 3% sucrose, 0.6% agar, pH 5.7. Calli derived from the R-biotype of E. indica possessed a high resistance to trifluralin (dinitroaniline herbicide) and cross-resistance to a structurally non-related herbicide, amiprophosmethyl (phosphorothioamidate herbicide), as did the original resistant plants. Embryogenic cell suspension culture was a better source of E. indica protoplasts than callus or mesophyll tissue. The enzyme solution containing 1.5% cellulase Onozuka R-10, 0.5% driselase, 1% pectolyase Y-23, 0.5% hemicellulase and N(6) mineral salts with an additional 0.2 M KCl and 0.1 M CaCl(2) (pH 5.4-5.5) was used for protoplast isolation. The purified protoplasts were cultivated in KM8p liquid medium supplemented with 2 mg l(-1) 2,4-D and 0.2 mg l(-1) Kn.

  16. Polyamines Interact with Hydroxyl Radicals in Activating Ca2+ and K+ Transport across the Root Epidermal Plasma Membranes1[W

    PubMed Central

    Zepeda-Jazo, Isaac; Velarde-Buendía, Ana María; Enríquez-Figueroa, René; Bose, Jayakumar; Shabala, Sergey; Muñiz-Murguía, Jesús; Pottosin, Igor I.

    2011-01-01

    Reactive oxygen species (ROS) are integral components of the plant adaptive responses to environment. Importantly, ROS affect the intracellular Ca2+ dynamics by activating a range of nonselective Ca2+-permeable channels in plasma membrane (PM). Using patch-clamp and noninvasive microelectrode ion flux measuring techniques, we have characterized ionic currents and net K+ and Ca2+ fluxes induced by hydroxyl radicals (OH•) in pea (Pisum sativum) roots. OH•, but not hydrogen peroxide, activated a rapid Ca2+ efflux and a more slowly developing net Ca2+ influx concurrent with a net K+ efflux. In isolated protoplasts, OH• evoked a nonselective current, with a time course and a steady-state magnitude similar to those for a K+ efflux in intact roots. This current displayed a low ionic selectivity and was permeable to Ca2+. Active OH•-induced Ca2+ efflux in roots was suppressed by the PM Ca2+ pump inhibitors eosine yellow and erythrosine B. The cation channel blockers gadolinium, nifedipine, and verapamil and the anionic channel blockers 5-nitro-2(3-phenylpropylamino)-benzoate and niflumate inhibited OH•-induced ionic currents in root protoplasts and K+ efflux and Ca2+ influx in roots. Contrary to expectations, polyamines (PAs) did not inhibit the OH•-induced cation fluxes. The net OH•-induced Ca2+ efflux was largely prolonged in the presence of spermine, and all PAs tested (spermine, spermidine, and putrescine) accelerated and augmented the OH•-induced net K+ efflux from roots. The latter effect was also observed in patch-clamp experiments on root protoplasts. We conclude that PAs interact with ROS to alter intracellular Ca2+ homeostasis by modulating both Ca2+ influx and efflux transport systems at the root cell PM. PMID:21980172

  17. Do phosphoinositides regulate membrane water permeability of tobacco protoplasts by enhancing the aquaporin pathway?

    PubMed

    Ma, Xiaohong; Shatil-Cohen, Arava; Ben-Dor, Shifra; Wigoda, Noa; Perera, Imara Y; Im, Yang Ju; Diminshtein, Sofia; Yu, Ling; Boss, Wendy F; Moshelion, Menachem; Moran, Nava

    2015-03-01

    Enhancing the membrane content of PtdInsP 2 , the already-recognized protein-regulating lipid, increased the osmotic water permeability of tobacco protoplasts, apparently by increasing the abundance of active aquaporins in their membranes. While phosphoinositides are implicated in cell volume changes and are known to regulate some ion channels, their modulation of aquaporins activity has not yet been reported for any organism. To examine this, we compared the osmotic water permeability (P f) of protoplasts isolated from tobacco (Nicotiana tabacum) cultured cells (NT1) with different (genetically lowered or elevated relative to controls) levels of inositol trisphosphate (InsP3) and phosphatidyl inositol [4,5] bisphosphate (PtdInsP2). To achieve this, the cells were transformed with, respectively, the human InsP3 5-phosphatase ('Ptase cells') or human phosphatidylinositol (4) phosphate 5-kinase ('PIPK cells'). The mean P f of the PIPK cells was several-fold higher relative to that of controls and Ptase cells. Three results favor aquaporins over the membrane matrix as underlying this excessive P f: (1) transient expression of the maize aquaporin ZmPIP2;4 in the PIPK cells increased P f by 12-30 μm s(-1), while in the controls only by 3-4 μm s(-1). (2) Cytosol acidification-known to inhibit aquaporins-lowered the P f in the PIPK cells down to control levels. (3) The transcript of at least one aquaporin was elevated in the PIPK cells. Together, the three results demonstrate the differences between the PIPK cells and their controls, and suggest a hitherto unobserved regulation of aquaporins by phosphoinositides, which could occur through direct interaction or indirect phosphoinositides-dependent cellular effects.

  18. Regeneration of somatic hybrids in relation to the nuclear and cytoplasmic genomes of wheat and Setaria italica.

    PubMed

    Xiang, Fengning; Xia, Guangmin; Zhi, Daying; Wang, Jing; Nie, Hui; Chen, Huimin

    2004-08-01

    Somatic hybridization via PEG (Polyethylene 6000)-mediated protoplast fusion was achieved between two different wheat culture lines (Triticum aestivum L., "Jinan"177, T1 and T2) and Setaria italica (L.) P. Beauv. The T1 recipient originated from non-regenerable long-term cell suspensions, while T2 was derived from embryogenic calli with a high regeneration capacity. Donor protoplasts were obtained from embryogenic calli of S. italica (S) (with low regeneration capacity) irradiated with different doses of ultraviolet light. Twenty-three putative hybrid cell lines were produced in fusion combinations with the donor protoplasts treated with UV light for 30 s (combination I) and 1 min (combination II), but only one (from combination II) differentiated into green plants. Three cell lines from combination I and five cell lines from combination II possessed the nuclear genomes of T1, T2, and S. italica as revealed by cytological, isozyme, RAPD, and 5S rDNA spacer sequence analyses. Genomic in situ hybridization (GISH) analysis showed that most hybrid cell lines had 22-36 wheat chromosomes, 0-2 S. italica chromosomes, and 1-6 wheat - S. italica recombinant chromosomes, whereas the regenerable cell line had 44-56 wheat chromosomes and 3-6 recombinant chromosomes, but no intact S. italica chromosomes. RFLP analysis of organellar DNA revealed that mitochondrial and chloroplast DNA of both parents coexisted in all hybrid cell lines and recombined in most hybrid cell lines. These results indicate that the regeneration of hybrid plants involves not only the integration of S. italica nuclear and organellar DNA, but also the genome complementation of T1 and T2.

  19. Micropropagation, genetic engineering, and molecular biology of Populus

    Treesearch

    N. B. Klopfenstein; Y. W. Chun; M. -S. Kim; M. A. Ahuja; M. C. Dillon; R. C. Carman; L. G. Eskew

    1997-01-01

    Thirty-four Populus biotechnology chapters, written by 85 authors, are comprised in 5 sections: 1) in vitro culture (micropropagation, somatic embryogenesis, protoplasts, somaclonal variation, and germplasm preservation); 2) transformation and foreign gene expression; 3) molecular biology (molecular/genetic characterization); 4) biotic and abiotic resistance (disease,...

  20. Construction and Analysis of High-Ethanol-Producing Fusants with Co-Fermentation Ability through Protoplast Fusion and Double Labeling Technology

    PubMed Central

    Ge, Jingping; Zhao, Jingwen; Zhang, Luyan; Zhang, Mengyun; Ping, Wenxiang

    2014-01-01

    Double labeling of resistance markers and report genes can be used to breed engineered Saccharomyces cerevisiae strains that can assimilate xylose and glucose as a mixed carbon source for ethanol fermentation and increased ethanol production. In this study Saccharomyces cerevisiae W5 and Candida shehatae 20335 were used as parent strains to conduct protoplast fusion and the resulting fusants were screened by double labeling. High performance liquid chromatography (HPLC) was used to assess the ethanol yield following the fermentation of xylose and glucose, as both single and mixed carbon sources, by the fusants. Interestingly, one fusant (ZLYRHZ7) was demonstrated to have an excellent fermentation performance, with an ethanol yield using the mixed carbon source of 0.424 g g−1, which compares with 0.240 g g−1 (W5) and 0.353 g g−1 (20335) for the parent strains. This indicates an improvement in the ethanol yield of 43.4% and 16.7%, respectively. PMID:25268957

  1. [The effect of dexamethoxin on the integrity of cytoplasmic membrane in gram-positive and gram-negative microorganisms].

    PubMed

    Shchetina, V N; Belanov, E F; Starobinets, Z G; Volianskiĭ, Iu L

    1990-01-01

    Decamethoxin is shown to be able to increase membrane permeability of Pseudomonas aeruginosa, Escherichia coli and Micrococcus lysodeikticus, that is confirmed by a loss of compounds with the absorption maximum at 260 nm by cells. Parallel with this the number of viable individuals has fallen and activity of dehydrogenases has been inhibited. The aspartate and alanine aminotransferase activity was not inhibited by decamethoxin and even increased. Decamethoxin lysed the protoplasts of the tested microorganisms. At high decamethoxin concentrations (over 500 micrograms/ml for P. aeruginosa and over 200 mu/ml--for E. coli) the outflow of components from the cells of gram-negative bacteria ceased, that may be associated with the coagulation changes in the cytoplasm. A loss of the low-molecular components by M. lysodeikticus cells and lysis of protoplasts proceeded less intensely than the same processes in the gram-negative microorganisms, that is explained by a less resistance of M. lysodeikticus to decamethoxin and earlier coagulation of the cytoplasm preventing lysis.

  2. Crown gall transformation of tobacco callus cells by cocultivation with Agrobacterium tumefaciens

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Muller, A.; Manzara, T.; Lurquin, P.F.

    1984-09-17

    Incubation of cells from squashed tobacco callus tissue with virulent Agrobacterium tumefaciens leads to the production of cells displaying a crown gall phenotype. In vitro crown gall transformation of dicotyledonous plant cells has been demonstrated after cocultivation of cell-wall regenerating mesophyll protoplasts with Agrobacterium tumefaciens cells. In addition, it has been shown that protoplasts freshly isolated from suspension cultures, when treated with A. tumefaciens spheroplasts and a fusogen, also generated cells displaying a typical crown gall phenotype, i.e., phytohormone-independent growth and opine synthesis. Subsequently, both techniques were used to transfer and express foreign genes in plant cells via A. tumefaciensmore » T-DNA integration. For practical purposes, it would be advantageous to be able to perform crown gall transformation of plant cells in tissue culture. The authors report here for the first time the production of Nicotiana tabacum crown gall cells after cocultivation of callus tissue with A. tumefaciens A136 cells. 11 references, 1 figure, 1 table.« less

  3. Dielectrophoretic spectra of single cells determined by feedback-controlled levitation.

    PubMed Central

    Kaler, K V; Jones, T B

    1990-01-01

    In this paper we have utilized the principle of dielectrophoresis (DEP) to develop an apparatus to stably levitate single biological cells using a digital feedback control scheme. Using this apparatus, the positive DEP spectra of both Canola plant protoplast and ligament fibroblast cells have been measured over a wide range of frequencies (1 kHz to 50 MHz) and suspending medium conductivities (11-800 muS/cm). The experimental data thus obtained have been interpreted in terms of a simple spherical cell model. Furthermore, utilizing such a model, we have shown that various cellular parameters of interest can be readily obtained from the measured DEP levitation spectrum. Specifically, the effective membrane capacitance of single cells has been determined. Values of 0.47 +/- 0.03 muF/cm2 for Canola protoplasts and 1.52 +/- 0.26 muF/cm2 for ligament fibroblasts thus obtained are consistent with those determined by other existing electrical methods. Images FIGURE A1 PMID:2317544

  4. Polyploidization facilitates biotechnological in vitro techniques in the genus Cucumis.

    PubMed

    Skálová, Dagmar; Ondřej, Vladan; Doležalová, Ivana; Navrátilová, Božena; Lebeda, Aleš

    2010-01-01

    Prezygotic interspecific crossability barrier in the genus Cucumis is related to the ploidy level of the species (cucumber (C. sativus), x = 7; muskmelon (C. melo) and wild Cucumis species, x = 12). Polyploidization of maternal plants helps hybridization among other Cucumis species by overcoming prezygotic genetic barriers. The main objective of this paper is to compare the results of several methods supporting interspecific crosses in cucumber without and with polyploidization (comparison between diploid (2x) and mixoploid (2x/4x) cucumber maternal plants). Mixoploid plants were obtained after in vivo and in vitro polyploidization by colchicine and oryzalin. Ploidy level was estimated by flow cytometry. Embryo rescue, in vitro pollination, and isolation of mesophyll protoplast were tested and compared. Positive effect of polyploidization was observed during all experiments presented by higher regeneration capacity of cultivated mixoploid cucumber embryos, ovules, and protoplasts. Nevertheless, the hybrid character of putative hybrid accessions obtained after cross in vivo and in vitro pollination was not confirmed.

  5. Polyploidization Facilitates Biotechnological In Vitro Techniques in the Genus Cucumis

    PubMed Central

    Skálová, Dagmar; Ondřej, Vladan; Doležalová, Ivana; Navrátilová, Božena; Lebeda, Aleš

    2010-01-01

    Prezygotic interspecific crossability barrier in the genus Cucumis is related to the ploidy level of the species (cucumber (C. sativus), x = 7; muskmelon (C. melo) and wild Cucumis species, x = 12). Polyploidization of maternal plants helps hybridization among other Cucumis species by overcoming prezygotic genetic barriers. The main objective of this paper is to compare the results of several methods supporting interspecific crosses in cucumber without and with polyploidization (comparison between diploid (2x) and mixoploid (2x/4x) cucumber maternal plants). Mixoploid plants were obtained after in vivo and in vitro polyploidization by colchicine and oryzalin. Ploidy level was estimated by flow cytometry. Embryo rescue, in vitro pollination, and isolation of mesophyll protoplast were tested and compared. Positive effect of polyploidization was observed during all experiments presented by higher regeneration capacity of cultivated mixoploid cucumber embryos, ovules, and protoplasts. Nevertheless, the hybrid character of putative hybrid accessions obtained after cross in vivo and in vitro pollination was not confirmed. PMID:21234406

  6. Production of Trichoderma strains with pesticide-polyresistance by mutagenesis and protoplast fusion.

    PubMed

    Hatvani, Lóránt; Manczinger, László; Kredics, László; Szekeres, András; Antal, Zsuzsanna; Vágvölgyi, Csaba

    2006-01-01

    The sensitivity of two cold-tolerant Trichoderma strains belonging to the species T. harzianum and T. atroviride was determined to a series of pesticides widely used in agriculture. From the 16 pesticides tested, seven fungicides: copper sulfate, carbendazim, mancozeb, tebuconazole, imazalil, captan and thiram inhibited colony growth of the test strains significantly with minimal inhibitory concentrations of 300, 0.4, 50, 100, 100, 100 and 50 microg/ml, respectively. Mutants resistant to carbendazim and tebuconazole were produced from both wild type strains by means of UV-mutagenesis. The cross-resistance capabilities and in vitro antagonistic properties of the mutants were determined. Carbendazim-resistant mutants showed total cross-resistance to benomyl and thiabendazole at a concentration of 20 microg/ml. Intraspecific protoplast fusion was carried out between carbendazim- and tebuconazole-resistant mutants of both parental strains, and putative haploid recombinants with stable resistance to both pesticides were produced in the case of T. atroviride. These pesticide-polyresistant progenies are potential candidates for application in an integrated pest management system.

  7. In Vitro Formation of Plant RNA-Induced Silencing Complexes Using an Extract of Evacuolated Tobacco Protoplasts.

    PubMed

    Iki, Taichiro; Ishikawa, Masayuki; Yoshikawa, Manabu

    2017-01-01

    Small RNA-mediated gene silencing is involved in a variety of biological processes among many eukaryotic organisms. The silencing effector, generally referred to as RNA-induced silencing complex (RISC), comprises an ARGONAUTE (AGO) protein and a small single-stranded guide RNA in its core. RISCs recognize target genes containing sequences complementary to the guide RNA and repress their expression transcriptionally or posttranscriptionally. In vitro systems that recapitulate RISC assembly are useful not only to decipher the molecular mechanisms underlying the assembly process itself but also to dissect the downstream silencing pathways mediated by RISCs. Here, we describe a method for in vitro plant RISC assembly, which relies on an extract of evacuolated protoplasts derived from Nicotiana tabacum BY-2 suspension-cultured cells. In this extract, synthetic duplexes of small RNAs are incorporated into AGO proteins that are synthesized by in vitro translation, and then duplex unwinding and selective strand elimination result in formation of mature RISCs.

  8. In vitro synthesis of cellulose microfibrils by a membrane protein from protoplasts of the non-vascular plant Physcomitrella patens.

    PubMed

    Cho, Sung Hyun; Du, Juan; Sines, Ian; Poosarla, Venkata Giridhar; Vepachedu, Venkata; Kafle, Kabindra; Park, Yong Bum; Kim, Seong H; Kumar, Manish; Nixon, B Tracy

    2015-09-01

    Plant cellulose synthases (CesAs) form a family of membrane proteins that are associated with hexagonal structures in the plasma membrane called CesA complexes (CSCs). It has been difficult to purify plant CesA proteins for biochemical and structural studies. We describe CesA activity in a membrane protein preparation isolated from protoplasts of Physcomitrella patens overexpressing haemagglutinin (HA)-tagged PpCesA5. Incubating the membrane preparation with UDP-glucose predominantly produced cellulose. Negative-stain EM revealed microfibrils. Cellulase bound to and degraded these microfibrils. Vibrational sum frequency generation (SFG) spectroscopic analysis detected the presence of crystalline cellulose in the microfibrils. Putative CesA proteins were frequently observed attached to the microfibril ends. Combined cross-linking and gradient centrifugation showed bundles of cellulose microfibrils with larger particle aggregates, possibly CSCs. These results suggest that P. patens is a useful model system for biochemical and structural characterization of plant CSCs and their components. © 2015 Authors; published by Portland Press Limited.

  9. Transient GFP expression in Nicotiana plumbaginifolia suspension cells: the role of gene silencing, cell death and T-DNA loss.

    PubMed

    Weld, R; Heinemann, J; Eady, C

    2001-03-01

    The transient nature of T-DNA expression was studied with a gfp reporter gene transferred to Nicotiana plumbaginifolia suspension cells from Agrobacterium tumefaciens. Individual GFP-expressing protoplasts were isolated after 4 days' co-cultivation. The protoplasts were cultured without selection and 4 weeks later the surviving proto-calluses were again screened for GFP expression. Of the proto-calluses initially expressing GFP, 50% had lost detectable GFP activity during the first 4 weeks of culture. Multiple T-DNA copies of the gfp gene were detected in 10 of 17 proto-calluses lacking visible GFP activity. The remaining 7 cell lines contained no gfp sequences. Our results confirm that transiently expressed T-DNAs can be lost during growth of somatic cells and demonstrate that transiently expressing cells frequently integrate multiple T-DNAs that become silenced. In cells competent for DNA uptake, cell death and gene silencing were more important barriers to the recovery of stably expressing transformants than lack of T-DNA integration.

  10. Targeted Gene Deletion in Cordyceps militaris Using the Split-Marker Approach.

    PubMed

    Lou, HaiWei; Ye, ZhiWei; Yun, Fan; Lin, JunFang; Guo, LiQiong; Chen, BaiXiong; Mu, ZhiXian

    2018-05-01

    The macrofungus Cordyceps militaris contains many kinds of bioactive ingredients that are regulated by functional genes, but the functions of many genes in C. militaris are still unknown. In this study, to improve the frequency of homologous integration, a genetic transformation system based on a split-marker approach was developed for the first time in C. militaris to knock out a gene encoding a terpenoid synthase (Tns). The linear and split-marker deletion cassettes were constructed and introduced into C. militaris protoplasts by PEG-mediated transformation. The transformation of split-marker fragments resulted in a higher efficiency of targeted gene disruption than the transformation of linear deletion cassettes did. The color phenotype of the Tns gene deletion mutants was different from that of wild-type C. militaris. Moreover, a PEG-mediated protoplast transformation system was established, and stable genetic transformants were obtained. This method of targeted gene deletion represents an important tool for investigating the role of C. militaris genes.

  11. Quantitative characterization of genetic parts and circuits for plant synthetic biology.

    PubMed

    Schaumberg, Katherine A; Antunes, Mauricio S; Kassaw, Tessema K; Xu, Wenlong; Zalewski, Christopher S; Medford, June I; Prasad, Ashok

    2016-01-01

    Plant synthetic biology promises immense technological benefits, including the potential development of a sustainable bio-based economy through the predictive design of synthetic gene circuits. Such circuits are built from quantitatively characterized genetic parts; however, this characterization is a significant obstacle in work with plants because of the time required for stable transformation. We describe a method for rapid quantitative characterization of genetic plant parts using transient expression in protoplasts and dual luciferase outputs. We observed experimental variability in transient-expression assays and developed a mathematical model to describe, as well as statistical normalization methods to account for, this variability, which allowed us to extract quantitative parameters. We characterized >120 synthetic parts in Arabidopsis and validated our method by comparing transient expression with expression in stably transformed plants. We also tested >100 synthetic parts in sorghum (Sorghum bicolor) protoplasts, and the results showed that our method works in diverse plant groups. Our approach enables the construction of tunable gene circuits in complex eukaryotic organisms.

  12. Construction and analysis of high-ethanol-producing fusants with co-fermentation ability through protoplast fusion and double labeling technology.

    PubMed

    Ge, Jingping; Zhao, Jingwen; Zhang, Luyan; Zhang, Mengyun; Ping, Wenxiang

    2014-01-01

    Double labeling of resistance markers and report genes can be used to breed engineered Saccharomyces cerevisiae strains that can assimilate xylose and glucose as a mixed carbon source for ethanol fermentation and increased ethanol production. In this study Saccharomyces cerevisiae W5 and Candida shehatae 20335 were used as parent strains to conduct protoplast fusion and the resulting fusants were screened by double labeling. High performance liquid chromatography (HPLC) was used to assess the ethanol yield following the fermentation of xylose and glucose, as both single and mixed carbon sources, by the fusants. Interestingly, one fusant (ZLYRHZ7) was demonstrated to have an excellent fermentation performance, with an ethanol yield using the mixed carbon source of 0.424 g g-1, which compares with 0.240 g g-1 (W5) and 0.353 g g-1 (20335) for the parent strains. This indicates an improvement in the ethanol yield of 43.4% and 16.7%, respectively.

  13. Protoplast transformation in coryneform bacteria and introduction of an alpha-amylase gene from Bacillus amyloliquefaciens into Brevibacterium lactofermentum.

    PubMed Central

    Smith, M D; Flickinger, J L; Lineberger, D W; Schmidt, B

    1986-01-01

    The goal of this study was to investigate the likelihood of developing useful transformation systems for coryneform bacteria. Two species of coryneform bacteria, Brevibacterium lactofermentum and Corynebacterium lilium, were transformed with chimeras constructed from pUB110 and a cryptic coryneform plasmid (pGX1901). C. lilium protoplasts were also efficiently transfected with phage CS1 DNA. High transformation and transfection frequencies were obtained after only 2 min of lysozyme treatment of lysozyme-sensitive mutants. A series of experiments was also conducted to determine whether DNA from other species of important industrial microbes from the genus Bacillus could be expressed in coryneform bacteria. Evidence of restriction of Bacillus subtilis DNA by B. lactofermentum was observed but could be overcome. A Bacillus amyloliquefaciens alpha-amylase gene (amyEBamP) was subcloned onto a plasmid able to replicate in B. lactofermentum. B. lactofermentum transformants for this plasmid expressed amylase activity and produced material cross-reactive to amylase antibody. Images PMID:3008649

  14. Tobacco Policy/Regulatory Factors - Prevention Summary Table | Cancer Trends Progress Report

    Cancer.gov

    The Cancer Trends Progress Report, first issued in 2001, summarizes our nation's advances against cancer in relation to Healthy People targets set forth by the Department of Health and Human Services.

  15. Bladder, Breast, and Colorectal Cancer- Treatment Summary Table | Cancer Trends Progress Report

    Cancer.gov

    The Cancer Trends Progress Report, first issued in 2001, summarizes our nation's advances against cancer in relation to Healthy People targets set forth by the Department of Health and Human Services.

  16. Incidence and Stage at Diagnosis - Diagnosis Summary Table | Cancer Trends Progress Report

    Cancer.gov

    The Cancer Trends Progress Report, first issued in 2001, summarizes our nation's advances against cancer in relation to Healthy People targets set forth by the Department of Health and Human Services.

  17. Weight and Physical Activity - Prevention Summary Table | Cancer Trends Progress Report

    Cancer.gov

    The Cancer Trends Progress Report, first issued in 2001, summarizes our nation's advances against cancer in relation to Healthy People targets set forth by the Department of Health and Human Services.

  18. Research and Technology Objectives and Plans Summary (RTOPS)

    NASA Technical Reports Server (NTRS)

    1982-01-01

    A compilation of summary portions of each of the Research and Technology Objectives and Plans (RTOPS) used for management review and control of research currently in progress throughout NASA is presented. Subject, technical monitors, responsible NASA organization, and RTOP number indexes are included.

  19. Research and Technology Objectives and Plans Summary (RTOPS)

    NASA Technical Reports Server (NTRS)

    1981-01-01

    A compilation of the summary portions of each of the Research and Technology Objective Plans (RTOP) used for management review and control of research currently in progress throughout NASA is presented. Indexes include: subject, technical monitor, responsible NASA organization, and RTOP number.

  20. Research and Technology Objectives and Plans (RTOP), summary

    NASA Technical Reports Server (NTRS)

    1982-01-01

    A compilation of summary portions of each of the Research and Technology Operating Plans (RTOPS) used for management review and control of research currently in progress throughout NASA is presented. Subject, technical monitor, responsible NASA organization, and RTOP number indexes are included.

  1. Research and Technology Objectives and Plans Summary (RTOPS)

    NASA Technical Reports Server (NTRS)

    1980-01-01

    A compilation of the summary portions of each of the Research and Technology Objectives and Plans (RTOPS) used for management review and control research currently in progress throughout NASA is presented. Indexes include: subject, technical monitor, responsible NASA organization, and RTOP number.

  2. Biology Division. Progress report, August 1, 1982-September 30, 1983

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1984-01-01

    The Biology Division is the component of the Oak Ridge National Laboratory that investigates the potential adverse health effects of energy-related substances. The body of this report provides summaries of the aims, scope and progress of the research of groups of investigators in the Division during the period of August 1, 1982, through September 30, 1983. At the end of each summary is a list of publications covering the same period (published or accepted for publication). For convenience, the summaries are assembled under Sections in accordance with the current organizational structure of the Biology Division; each Section begins with anmore » overview. It will be apparent, however, that currents run throughout the Division and that the various programs support and interact with each other.« less

  3. Site-specific accumulation and dynamic change of flavonoids in Apocyni Veneti Folium.

    PubMed

    Chen, Cui-Hua; Xu, Hu; Liu, Xun-Hong; Zou, Li-Si; Wang, Mei; Liu, Zi-Xiu; Fu, Xing-Sheng; Zhao, Hui; Yan, Ying

    2017-12-01

    Site-specific accumulation of flavonoids in Apocyni Veneti Folium was determined by laser scanning confocal microscope (LSCM) and the localization of catechins also was observed via vanillin-HCl staining under the conventional optical microscope. The contents of five flavonoids in Apocyni Veneti Folium from different harvest times and growth parts were measured using HPLC method. LSCM observation showed that flavonoids are accumulated in cuticle of epidermal cells and vessel walls, especially in protoplasts and nucleolus of the collenchyma cells and the epidermal cells. Catechins are localized in the palisade parenchyma cells and vessel walls, particularly in the laticifers found in the phloem. On the basis of the difference of the maximal emission wavelength between quercetin and kaempferol derivatives which have fluorescence behavior by appropriate treatment, kaempferol and its derivatives are localized exclusively in the cuticle. Results showed that the content of astragalin in Apocyni Veneti Folium from different parts revealed the decreasing trend, while hyperin and isoquercitrin were higher in June and July analyzed by HPLC. In summary, the site-specific accumulation of flavonoids in Apocyni Veneti Folium can be determined by LSCM and vanillin-HCl staining. The contents of flavonoids in Apocyni Veneti Folium are correlated with harvest times and growth parts. © 2017 Wiley Periodicals, Inc.

  4. Financial Burden of Cancer Care - Life After Cancer Summary Table | Cancer Trends Progress Report

    Cancer.gov

    The Cancer Trends Progress Report, first issued in 2001, summarizes our nation's advances against cancer in relation to Healthy People targets set forth by the Department of Health and Human Services.

  5. Breast, Cervical, and Colorectal Cancers - Early Detection Summary Table | Cancer Trends Progress Report

    Cancer.gov

    The Cancer Trends Progress Report, first issued in 2001, summarizes our nation's advances against cancer in relation to Healthy People targets set forth by the Department of Health and Human Services.

  6. Kidney, Lung, Ovarian, and Prostate Cancer - Treatment Summary Table | Cancer Trends Progress Report

    Cancer.gov

    The Cancer Trends Progress Report, first issued in 2001, summarizes our nation's advances against cancer in relation to Healthy People targets set forth by the Department of Health and Human Services.

  7. UV Exposure and Sun-Protective Behavior - Prevention Summary Table | Cancer Trends Progress Report

    Cancer.gov

    The Cancer Trends Progress Report, first issued in 2001, summarizes our nation's advances against cancer in relation to Healthy People targets set forth by the Department of Health and Human Services.

  8. Cybridization of grapefruit with 'Dancy' mandarin leads to improved fruit characteristics

    USDA-ARS?s Scientific Manuscript database

    In cybridization, new combinations of nuclear and cytoplasmic genes result in a unique genotype that may bring cellular, physical, physiological and biochemical changes to the plant. This has been demonstrated in unexpected cybrids generated from the fusion of citrus protoplasts in two independent e...

  9. Research and Technology Operating Plan Summary, Fiscal Year 1972 Research and Technology Program

    NASA Technical Reports Server (NTRS)

    1971-01-01

    The NASA Research and Technology program for FY 1972 is presented. It is a compilation of the summary portions of each of the RTOPs (Research and Technology Operating Plan) used for management review and control of research currently in progress throughout NASA. The RTOP Summary is designed to facilitate communication and coordination among concerned technical personnel in government, in industry, and in universities.

  10. FNS Research Corner: Summary of Research

    ERIC Educational Resources Information Center

    Gola, Alice Ann H.; Burdg, Jinee

    2018-01-01

    The FNS Research Corner provides a continuing series to summarize recently completed and current research conducted by the U.S. Department of Agriculture's Food and Nutrition Service (FNS) in the area of child nutrition. Summaries of recently completed research projects and in-progress research are provided in this article.

  11. DIVISION OF ISOTOPES DEVELOPMENT RESEARCH AND DEVELOPMENT PROJECTS: 1968. Progress Reports on Sponsored Work.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    None

    1969-01-01

    This is the second edition of the Division of Isotopes Development project summaries. It presents a short summary of objectives, results, and future plans for each research or development project sponsored by the Division within each of eight program areas.

  12. Prototype solar heating and cooling systems

    NASA Technical Reports Server (NTRS)

    1979-01-01

    A combination of monthly progress reports are presented. It contains a summary of activities and progress made from November 1, 1978, to February 28, 1979. The effort calls for the development, manufacture, test, system installation, maintenance, problem resolution, and performance evaluation.

  13. Amarillo National Resource Center for Plutonium. Quarterly technical progress report, May 1, 1997--July 31, 1997

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    NONE

    Progress summaries are provided from the Amarillo National Center for Plutonium. Programs include the plutonium information resource center, environment, public health, and safety, education and training, nuclear and other material studies.

  14. Mortality and Person-Years of Life Lost - End of Life Summary Table | Cancer Trends Progress Report

    Cancer.gov

    The Cancer Trends Progress Report, first issued in 2001, summarizes our nation's advances against cancer in relation to Healthy People targets set forth by the Department of Health and Human Services.

  15. Survival, Smoking, Physical Activity, and Obesity - Life After Cancer Summary Table | Cancer Trends Progress Report

    Cancer.gov

    The Cancer Trends Progress Report, first issued in 2001, summarizes our nation's advances against cancer in relation to Healthy People targets set forth by the Department of Health and Human Services.

  16. Rapid deletion plasmid construction methods for protoplast and Agrobacterium based fungal transformation systems

    USDA-ARS?s Scientific Manuscript database

    Increasing availability of genomic data and sophistication of analytical methodology in fungi has elevated the need for functional genomics tools in these organisms. Gene deletion is a critical tool for functional analysis. The targeted deletion of genes requires both a suitable method for the trans...

  17. Children's Services Report Card, 1996: Measuring Minnesota's Progress for Children. Summary Report.

    ERIC Educational Resources Information Center

    Fong, Richard

    This report was developed by Minnesota Planning to help counties measure their progress toward meeting the Minnesota Milestones goals for social and educational services for children. The report card is composed of 21 indicators of children's well-being. Since the 1994 report card was released, Minnesota has made progress in eight areas (1) abused…

  18. Research and Technology Objectives and Plans Summary (RTOPS)

    NASA Technical Reports Server (NTRS)

    1979-01-01

    A compilation of the summary portions of each of the Research and Technology Operating Plans (RTOP) used for management review and control of research currently in progress throughout NASA is presented along with citations and abstracts of the RTOPs. Indexes include: subject; technical monitor; responsible NASA organization; and RTOP number.

  19. Research and Technology Operating Plan Summary: Fiscal Year 1973 Research and Technology Program

    NASA Technical Reports Server (NTRS)

    1972-01-01

    Abstracts are presented of each of the Research and Technology Operating Plans (RTOP) used for management review and control of research currently in progress throughout NASA. This RTOP Summary is designed to facilitate communication and coordination among concerned technical personnel in government, industry, and universities. The summary is arranged in five sections consisting of citations and abstracts of the RTOPs and subject, technical monitor, responsible NASA organization, and RTOP number indexes.

  20. 2010 Summary of Advances in Autism Spectrum Disorder Research

    ERIC Educational Resources Information Center

    Interagency Autism Coordinating Committee, 2010

    2010-01-01

    As part of the Combating Autism Act of 2006, the members of the Interagency Autism Coordinating Committee (IACC) are required to develop an annual "Summary of Advances" to describe each year's top advances in autism spectrum disorder (ASD) research. These advances represent significant progress in the early diagnosis of ASD, understanding the…

  1. Students Training for Academic Readiness (STAR): Year Three Evaluation Report. Executive Summary

    ERIC Educational Resources Information Center

    Texas Center for Educational Research, 2010

    2010-01-01

    This executive summary presents findings from the Year 3 evaluation of Texas' state-level Gaining Early Awareness and Readiness for Undergraduate Programs, or GEAR UP, grant. GEAR UP grant requirements include an evaluation component designed to assess program effectiveness and to measure progress toward project goals. To this end, the evaluation…

  2. The African American Education Data Book. Volume I: Higher and Adult Education. Executive Summary.

    ERIC Educational Resources Information Center

    Nettles, Michael T.; Perna, Laura W.

    This executive summary presents highlights drawn from the data compiled in "The African American Education Data Book, Volume I: Higher and Adult Education," the first broad national survey of the educational status, performance, progress, and financial support of African Americans in higher education and adult education. The report…

  3. Proteome reference maps of Medicago truncatula embryogenic cell cultures generated from single protoplasts.

    PubMed

    Imin, Nijat; De Jong, Femke; Mathesius, Ulrike; van Noorden, Giel; Saeed, Nasir A; Wang, Xin-Ding; Rose, Ray J; Rolfe, Barry G

    2004-07-01

    Using a combination of two-dimensional gel electrophoresis (2-DE) protein mapping and mass spectrometry (MS) analysis, we have established proteome reference maps of Medicago truncatula embryogenic tissue culture cells. The cultures were generated from single protoplasts, which provided a relatively homogeneous cell population. We used these to analyze protein expression at the globular stages of somatic embryogenesis, which is the earliest morphogenetic embryonic stage. Over 3000 proteins could reproducibly be resolved over a pI range of 4-11. Three hundred and twelve protein spots were extracted from colloidal Coomassie Blue-stained 2-DE gels and analyzed by matrix-assisted laser desorption/ionization-time of flight MS analysis and tandem MS sequencing. This enabled the identification of 169 protein spots representing 128 unique gene products using a publicly available expressed sequence tag database and the MASCOT search engine. These reference maps will be valuable for the investigation of the molecular events which occur during somatic embryogenesis in M. truncatula. The proteome reference maps and supplementary materials will be available and updated for public access at http://semele.anu.edu.au/.

  4. Molecular Breeding Algae For Improved Traits For The Conversion Of Waste To Fuels And Commodities.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bagwell, C.

    This Exploratory LDRD aimed to develop molecular breeding methodology for biofuel algal strain improvement for applications in waste to energy / commodity conversion technologies. Genome shuffling technologies, specifically protoplast fusion, are readily available for the rapid production of genetic hybrids for trait improvement and have been used successfully in bacteria, yeast, plants and animals. However, genome fusion has not been developed for exploiting the remarkable untapped potential of eukaryotic microalgae for large scale integrated bio-conversion and upgrading of waste components to valued commodities, fuel and energy. The proposed molecular breeding technology is effectively sexual reproduction in algae; though compared tomore » traditional breeding, the molecular route is rapid, high-throughput and permits selection / improvement of complex traits which cannot be accomplished by traditional genetics. Genome fusion technologies are the cutting edge of applied biotechnology. The goals of this Exploratory LDRD were to 1) establish reliable methodology for protoplast production among diverse microalgal strains, and 2) demonstrate genome fusion for hybrid strain production using a single gene encoded trait as a proof of the concept.« less

  5. Distribution of Metabolites between Chloroplast and Cytoplasm during the Induction Phase of Photosynthesis in Leaf Protoplasts 1

    PubMed Central

    Robinson, Simon P.; Walker, David A.

    1980-01-01

    A method for rapid separation of the chloroplast and cytoplasmic fractions from isolated leaf protoplasts of wheat and spinach has been used to determine the distribution of 14C-labeled products during photosynthesis. In the dark, CO2 fixation was only 1 to 2% of that in the light and the products were mainly in the cytoplasmic fraction suggesting fixation by phosphoenolpyruvate carboxylase. Label appeared rapidly in the chloroplast fraction following illumination but the amount leveled off after 4 to 5 minutes reflecting the buildup of intermediates to steady state levels. There was only a slight lag before label appeared in the cytoplasmic fraction and it continued to increase at a constant rate reflecting synthesis of neutral products. In the light, the percentage of label in the chloroplast fraction decreased rapidly in the first minute of illumination and was only 10 to 20% in the steady-state. It is suggested that the chloroplast phosphate transporter promotes a rapid transfer of sugar phosphates from the chloroplast to the cytoplasm, even during the induction phase of photosynthesis. PMID:16661305

  6. Phospholipid composition of chlorophyll-free mitochondria isolated via protoplasts from oat mesophyll cells.

    PubMed

    Fuchs, R; Haas, R; Wrage, K; Heinz, E

    1981-08-01

    Mitochondria were isolated from oat primary leaves via mesophyll protoplasts and subjected to phospholipid analysis. In mesophyll cells mitochondria account for only small proportions of cellular phospholipids (in the order of 5%) and proteins (in the order of 2%). Contamination by lipids from other membranes was insignificant as indicated by the absence or very low levels of chlorophyll, galactolipids and steryl glycosides. The absence of 3-trans-hexadecenoic acid in phosphatidylglycerol from mitochondria of green cells serves an an additional criterion of purity. The phospholipid mixture extracted from these mitochondria resembles phospholipids in mitochondria from non-green tissues regarding composition as well as fatty acid profiles. Therefore, mitochondria maintain a rather constant lipid profile and in contrast to plastids do not respond at this level to differences in the physiological status of their housing cell. Palmitic acid in mitochondrial phosphatidylcholine and phosphatidylethanolamine is primarily localized at the C-1 position of the glycerol moiety. Two enzymatic activities so far not described in mitochondria, formation of acylgalactosyl diacylglycerol and hydrolysis of acyl-CoA, were found in the purified mitochondrial fraction.

  7. Molecular transformation, gene cloning, and gene expression systems for filamentous fungi

    USGS Publications Warehouse

    Gold, Scott E.; Duick, John W.; Redman, Regina S.; Rodriguez, Rusty J.

    2001-01-01

    This chapter discusses the molecular transformation, gene cloning, and gene expression systems for filamentous fungi. Molecular transformation involves the movement of discrete amounts of DNA into cells, the expression of genes on the transported DNA, and the sustainable replication of the transforming DNA. The ability to transform fungi is dependent on the stable replication and expression of genes located on the transforming DNA. Three phenomena observed in bacteria, that is, competence, plasmids, and restriction enzymes to facilitate cloning, were responsible for the development of molecular transformation in fungi. Initial transformation success with filamentous fungi, involving the complementation of auxotrophic mutants by exposure to sheared genomic DNA or RNA from wt isolates, occurred with low transformation efficiencies. In addition, it was difficult to retrieve complementing DNA fragments and isolate genes of interest. This prompted the development of transformation vectors and methods to increase efficiencies. The physiological studies performed with fungi indicated that the cell wall could be removed to generate protoplasts. It was evident that protoplasts could be transformed with significantly greater efficiencies than walled cells.

  8. Genome editing in the mushroom-forming basidiomycete Coprinopsis cinerea, optimized by a high-throughput transformation system.

    PubMed

    Sugano, Shigeo S; Suzuki, Hiroko; Shimokita, Eisuke; Chiba, Hirofumi; Noji, Sumihare; Osakabe, Yuriko; Osakabe, Keishi

    2017-04-28

    Mushroom-forming basidiomycetes produce a wide range of metabolites and have great value not only as food but also as an important global natural resource. Here, we demonstrate CRISPR/Cas9-based genome editing in the model species Coprinopsis cinerea. Using a high-throughput reporter assay with cryopreserved protoplasts, we identified a novel promoter, CcDED1 pro , with seven times stronger activity in this assay than the conventional promoter GPD2. To develop highly efficient genome editing using CRISPR/Cas9 in C. cinerea, we used the CcDED1 pro to express Cas9 and a U6-snRNA promoter from C. cinerea to express gRNA. Finally, CRISPR/Cas9-mediated GFP mutagenesis was performed in a stable GFP expression line. Individual genome-edited lines were isolated, and loss of GFP function was detected in hyphae and fruiting body primordia. This novel method of high-throughput CRISPR/Cas9-based genome editing using cryopreserved protoplasts should be a powerful tool in the study of edible mushrooms.

  9. Feeding infants and toddlers study 2008: progress, continuing concerns, and implications

    USDA-ARS?s Scientific Manuscript database

    The Feeding Infants and Toddlers Survey (FITS) 2008 reveals both progress and some continuing concerns about feeding American infants and toddlers in the 21st century. This summary integrates these findings and suggests possible implications for re-evaluating or clarifying dietary recommendations....

  10. Project Fire Model: Summary Progress Report - II, Period May 1, 1960 to April 30, 1962

    Treesearch

    W.L. Fons; H.B. Clements; E.R. Elliott; P.M. George

    1962-01-01

    This publication is included in a four part series. The other parts of the series can be found through the following links:Progress Report #1: http://www.fs.fed.us/psw/publications/fons/psw_1960_fons001.pdf...

  11. How to Get Information on Several Proven Programs for Accelerating the Progress of Low-Achieving Children (Literacy for All Children).

    ERIC Educational Resources Information Center

    Allington, Richard L.

    1992-01-01

    Offers summaries of three proven programs (Reading Recovery, Success for All, and Accelerated Schools) for accelerating the reading and writing progress of low-achieving, low-income children. Provides addresses for more information. (SR)

  12. External pH effects on the depolarization-activated K channels in guard cell protoplasts of Vicia faba

    PubMed Central

    1994-01-01

    Previous studies reveal that the pH of the apoplastic solution in the guard cell walls may vary between 7.2 and 5.1 in closed and open stomata, respectively. During these aperture and pH changes, massive K+ fluxes cross the cellular plasma membrane driving the osmotic turgor and volume changes of guard cells. Therefore, we examined the effect of extracellular pH on the depolarization-activated K channels (KD channels), which constitute the K+ efflux pathway, in the plasma membrane of Vicia faba guard cell protoplasts. We used patch clamp, both in whole cells as well as in excised outside-out membrane patches. Approximately 500 KD channels, at least, could be activated by depolarization in one protoplast (density: approximately 0.6 micron-2). Acidification from ph 8.1 to 4.4 decreased markedly the whole-cell conductance, GK, of the KD channels, shifted its voltage dependence, GK- EM, to the right on the voltage axis, slowed the rate of activation and increased the rate of deactivation, whereas the single channel conductance was not affected significantly. Based on the GK-EM shifts, the estimated average negative surface charge spacing near the KD channel is 39 A. To quantify the effects of protons on the rates of transitions between the hypothesized conformational states of the channels, we fitted the experimental macroscopic steady state conductance-voltage relationship and the voltage dependence of time constants of activation and deactivation, simultaneously, with a sequential three-state model CCO. In terms of this model, protonation affects the voltage-dependent properties via a decrease in localized, rather than homogeneous, surface charge sensed by the gating moieties. In terms of either the CO or CCO model, the protonation of a site with a pKa of 4.8 decreases the voltage-independent number of channels, N, that are available for activation by depolarization. PMID:8035163

  13. Characterization of mutant tobacco mosaic virus coat protein that interferes with virus cell-to-cell movement.

    PubMed

    Bendahmane, Mohammed; Szecsi, Judit; Chen, Iju; Berg, R Howard; Beachy, Roger N

    2002-03-19

    Expression of tobacco mosaic virus (TMV) coat protein (CP) in plants confers resistance to infection by TMV and related tobamoviruses. Certain mutants of the CP (CP(T42W)) provide much greater levels of resistance than wild-type (wt) CP. In the present work, infection induced by RNA transcripts of TMV clones that contain wt CP or mutant CP(T42W) fused to the green fluorescent protein (GFP) (TMV-CP:GFP, TMV-CP(T42W):GFP) and clones harboring TMV movement protein (MP):GFP were followed in nontransgenic and transgenic tobacco BY-2 protoplasts and Nicotiana tabaccum Xanthi-nn plants that express wt CP or CP(T42W). On nontransgenic and wt CP transgenic plants, TMV-CP:GFP produced expanding, highly fluorescent disk-shaped areas. On plants expressing CP(T42W), infection by TMV-CP:GFP or TMV-MP:GFP-CP produced infection sites of smaller size that were characterized by low fluorescence, reflecting reduced levels of virus spread and reduced accumulation of both CP:GFP and MP:GFP. TMV-CP(T42W):GFP failed to produce visible infection sites on nontransgenic plants, yet produced normal infection sites on MP-transgenic plants that produce MP. TMV infection of transgenic BY-CP(T42W) protoplasts resulted in very low levels of MP accumulation, whereas on BY-CP protoplasts (containing wt CP), infection produced higher levels of MP than in nontransgenic BY-2 cells. The results suggest that wt CP has a positive effect on the production of MP, whereas the CP(T42W) has a negative effect on MP accumulation and/or function. This effect results in very high levels of resistance to TMV infection in plants containing CP(T42W). This report shows that the CP of a plant virus regulates production of the MP, and that a mutant CP interferes with MP accumulation and cell-to-cell movement of infection.

  14. Chemical Technology Division: Progress report, January 1, 1987--June 30, 1988

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1989-02-01

    This progress report summarizes the research and development efforts conducted in the Chemical Technology Division (Chem Tech) during the period January 1, 1987, to June 30, 1988. The following major areas are covered: waste management and environmental programs, radiochemical and reactor engineering programs, basic science and technology, Nuclear Regulatory Commission programs, and administrative resources and facilities. The Administrative Summary, an appendix, presents a comprehensive listing of publications, oral presentations, awards and recognitions, and patents of Chem Tech staff members during this period. A staffing level and financial summary and lists of seminars and Chem Tech consultants for the period aremore » also included.« less

  15. Research and Technology Objectives and Plans Summary (RTOPS)

    NASA Technical Reports Server (NTRS)

    1990-01-01

    The NASA research and technology program for FY 1990 is presented. The summary portions is compiled of each of the RTOPs (Research and Technology Objectives and Plans) used for management review and control of research currently in progress throughout NASA. The RTOP summary is designed to facilitate communication and coordination among concerned technical personnel in government, industry, and universities. The first section containing citations and abstracts of the RTOPs is followed by four indices: Subject; Technical Monitor; Responsible NASA Organization; and RTOP number.

  16. Testing the Importance of Individual Growth Curves in Predicting Performance on a High-Stakes Reading Comprehension Test in Florida. Summary. REL 2014-006

    ERIC Educational Resources Information Center

    Petscher, Yaacov; Kershaw, Sarah; Koon, Sharon; Foorman, Barbara R.

    2014-01-01

    Districts and schools use progress monitoring to assess student progress, to identify students who fail to respond to intervention, and to further adapt instruction to student needs. Researchers and practitioners often use progress monitoring data to estimate student achievement growth (slope) and evaluate changes in performance over time for…

  17. 78 FR 63875 - Progress Reports Rules Revision

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-25

    ... Reports Rules Revision AGENCY: Bureau of Prisons, Justice. ACTION: Final rule. SUMMARY: In this document, the Bureau of Prisons (Bureau) removes from regulations and/or modifies two types of progress reports: transfer reports and triennial reports. DATES: This rule is effective on November 25, 2013. FOR FURTHER...

  18. Advances in nonlinear optical materials and devices

    NASA Technical Reports Server (NTRS)

    Byer, Robert L.

    1991-01-01

    The recent progress in the application of nonlinear techniques to extend the frequency of laser sources has come from the joint progress in laser sources and in nonlinear materials. A brief summary of the progress in diode pumped solid state lasers is followed by an overview of progress in nonlinear frequency extension by harmonic generation and parametric processes. Improved nonlinear materials including bulk crystals, quasiphasematched interactions, guided wave devices, and quantum well intersubband studies are discussed with the idea of identifying areas of future progress in nonlinear materials and devices.

  19. Research and Technology Objectives and Plans Summary (RTOPS)

    NASA Technical Reports Server (NTRS)

    1976-01-01

    A compilation of the summary portion of each of the Research and Technology Operating Plans (RTOP) used for management review and control of research currently in progress throughout NASA is presented along with citations and abstracts of the RTOPs. Four indexes are included: (1) subject; (2) technical monitor; (3) responsible NASA organization; and (4) RTOP number.

  20. Race to the Top. Florida Report. Year 2: School Year 2011-2012. [State-Specific Summary Report

    ERIC Educational Resources Information Center

    US Department of Education, 2013

    2013-01-01

    This State-specific summary report serves as an assessment of Florida's Year 2 Race to the Top implementation, highlighting successes and accomplishments, identifying challenges, and providing lessons learned from implementation from approximately September 2011 through September 2012. In Year 2, the State made progress in executing contracts and…

  1. State geothermal commercialization programs in seven Rocky Mountain States. Semi-annual progress report, January-June 1980

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tuttle, J.; Coe, B.A.; Gertsch, W.D.

    The following are included: a summary of the state projects, a summary of findings, public outreach, and a description of the major conclusions and recommendations. The commercialization activities carried out by the state teams are described for Colorado, Montana, New Mexico, North Dakota, South Dakota, Utah, and Wyoming. (MHR)

  2. Children Achieving: Philadelphia's Education Reform. A Second-Year Evaluation. Executive Summary. Progress Report Series 1996-97.

    ERIC Educational Resources Information Center

    Consortium for Policy Research in Education, Philadelphia, PA.

    The 1996-97 school year was the second year of the Children Achieving reform initiative in Philadelphia (Pennsylvania). This summary describes findings from this second-year evaluation. The evaluation team conducted interviews and observations in 21 schools and 14 clusters, interviewing education reform leaders in the school district and…

  3. Getting Personal: Progress and Pitfalls in HIV Prevention among Latinas

    ERIC Educational Resources Information Center

    Amaro, Hortensia; Raj, Anita; Reed, Elizabeth; Ulibarri, Monica

    2011-01-01

    This article first presents the political, personal, and epidemiological context of Hortensia Amaro's 1988 publication in "Psychology of Women Quarterly" ("PWQ"), "Considerations for Prevention of HIV Infection Among Hispanic Women" (Amaro, 1988). Second, it provides a brief summary of progress in HIV prevention with Latinas. The third section…

  4. Biology Division annual progress report for period ending December 31, 1968

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    None

    1969-07-01

    Brief summaries are presented of research in progress in the fields of radiobiology, genetics, hematology, immunology, physsiology, biochemistry, bacteriology, enzymology, microbiology, photosynthesis, biophysics, radiation protection, and related fields. A list is included of 212 publications in the world literature that report results of completed studies. (CH)

  5. Cybrids between Dancy tangerine (Citrus reticulata Blanca) and Ruby Red grapefruit (C. paradisi Mafc.) for improvement of citrus fruit traits [abstract

    USDA-ARS?s Scientific Manuscript database

    In cybridization, new combinations of nuclear and cytoplasmic genes result in a unique genotype that may bring cellular, physical, physiological and biochemical changes to the plant. This has been demonstrated in cybrids generated from the fusion of citrus protoplasts in two independent experiments....

  6. A homokaryotic derivative of a Phanerochaete chrysosporium strain and its use in genomic analysis of repetitive elements

    Treesearch

    Philip Stewart; Jill Gaskell; Daniel Cullen

    2000-01-01

    Analysis of complex gene families in the lignin-degrading basidiomycete Phanerochaete chrysosporium has been hampered by the dikaryotic nuclear condition. To facilitate genetic investigations in P. chrysosporium strain BRM-F-1767, we isolated a homokaryon from regenerated protoplasts. The nuclear condition was established by PCR amplification of five unlinked genes...

  7. Imaging and Spectroscopy of Natural Fluorophores in Pine Needles

    PubMed Central

    Williams, Nari

    2018-01-01

    Many plant tissues fluoresce due to the natural fluorophores present in cell walls or within the cell protoplast or lumen. While lignin and chlorophyll are well-known fluorophores, other components are less well characterized. Confocal fluorescence microscopy of fresh or fixed vibratome-cut sections of radiata pine needles revealed the presence of suberin, lignin, ferulate, and flavonoids associated with cell walls as well as several different extractive components and chlorophyll within tissues. Comparison of needles in different physiological states demonstrated the loss of chlorophyll in both chlorotic and necrotic needles. Necrotic needles showed a dramatic change in the fluorescence of extractives within mesophyll cells from ultraviolet (UV) excited weak blue fluorescence to blue excited strong green fluorescence associated with tissue browning. Comparisons were made among fluorophores in terms of optimal excitation, relative brightness compared to lignin, and the effect of pH of mounting medium. Fluorophores in cell walls and extractives in lumens were associated with blue or green emission, compared to the red emission of chlorophyll. Autofluorescence is, therefore, a useful method for comparing the histology of healthy and diseased needles without the need for multiple staining techniques, potentially aiding visual screening of host resistance and disease progression in needle tissue. PMID:29393922

  8. Biotechnological applications in in vitro plant regeneration studies of broccoli (Brassica oleracea L. var. italica), an important vegetable crop.

    PubMed

    Kumar, Pankaj; Srivastava, Dinesh Kumar

    2016-04-01

    Biotechnology holds promise for genetic improvement of important vegetable crops. Broccoli (Brassica oleracea L. var. italica) is an important vegetable crop of the family Brassicaceae. However, various biotic and abiotic stresses cause enormous crop yield losses during commercial cultivation of broccoli. Establishment of a reliable, reproducible and efficient in vitro plant regeneration system with cell and tissue culture is a vital prerequisite for biotechnological application of crop improvement programme. An in vitro plant regeneration technique refers to culturing, cell division, cell multiplication, de-differentiation and differentiation of cells, protoplasts, tissues and organs on defined liquid/solid medium under aseptic and controlled environment. Recent progress in the field of plant tissue culture has made this area one of the most dynamic and promising in experimental biology. There are many published reports on in vitro plant regeneration studies in broccoli including direct organogenesis, indirect organogenesis and somatic embryogenesis. This review summarizes those plant regeneration studies in broccoli that could be helpful in drawing the attention of the researchers and scientists to work on it to produce healthy, biotic and abiotic stress resistant plant material and to carry out genetic transformation studies for the production of transgenic plants.

  9. Post-Translational Modification and Secretion of Azelaic Acid Induced 1 (AZI1), a Hybrid Proline-Rich Protein from Arabidopsis

    PubMed Central

    Pitzschke, Andrea; Xue, Hui; Persak, Helene; Datta, Sneha; Seifert, Georg J.

    2016-01-01

    Arabidopsis EARLI-type hybrid proline-rich proteins (HyPRPs) consist of a putative N-terminal secretion signal, a proline-rich domain (PRD), and a characteristic eight-cysteine-motif (8-CM). They have been implicated in biotic and abiotic stress responses. AZI1 is required for systemic acquired resistance and it has recently been identified as a target of the stress-induced mitogen-activated protein kinase MPK3. AZI1 gel migration properties strongly indicate AZI1 to undergo major post-translational modifications. These occur in a stress-independent manner and are unrelated to phosphorylation by MAPKs. As revealed by transient expression of AZI1 in Nicotiana benthamiana and Tropaeolum majus, the Arabidopsis protein is similarly modified in heterologous plant species. Proline-rich regions, resembling arabinogalactan proteins point to a possible proline hydroxylation and subsequent O-glycosylation of AZI1. Consistently, inhibition of prolyl hydroxylase reduces its apparent protein size. AZI1 secretion was examined using Arabidopsis protoplasts and seedling exudates. Employing Agrobacterium-mediated leaf infiltration of N. benthamiana, we attempted to assess long-distance movement of AZI1. In summary, the data point to AZI1 being a partially secreted protein and a likely new member of the group of hydroxyproline-rich glycoproteins. Its dual location suggests AZI1 to exert both intra- and extracellular functions. PMID:26771603

  10. Post-Translational Modification and Secretion of Azelaic Acid Induced 1 (AZI1), a Hybrid Proline-Rich Protein from Arabidopsis.

    PubMed

    Pitzschke, Andrea; Xue, Hui; Persak, Helene; Datta, Sneha; Seifert, Georg J

    2016-01-12

    Arabidopsis EARLI-type hybrid proline-rich proteins (HyPRPs) consist of a putative N-terminal secretion signal, a proline-rich domain (PRD), and a characteristic eight-cysteine-motif (8-CM). They have been implicated in biotic and abiotic stress responses. AZI1 is required for systemic acquired resistance and it has recently been identified as a target of the stress-induced mitogen-activated protein kinase MPK3. AZI1 gel migration properties strongly indicate AZI1 to undergo major post-translational modifications. These occur in a stress-independent manner and are unrelated to phosphorylation by MAPKs. As revealed by transient expression of AZI1 in Nicotiana benthamiana and Tropaeolum majus, the Arabidopsis protein is similarly modified in heterologous plant species. Proline-rich regions, resembling arabinogalactan proteins point to a possible proline hydroxylation and subsequent O-glycosylation of AZI1. Consistently, inhibition of prolyl hydroxylase reduces its apparent protein size. AZI1 secretion was examined using Arabidopsis protoplasts and seedling exudates. Employing Agrobacterium-mediated leaf infiltration of N. benthamiana, we attempted to assess long-distance movement of AZI1. In summary, the data point to AZI1 being a partially secreted protein and a likely new member of the group of hydroxyproline-rich glycoproteins. Its dual location suggests AZI1 to exert both intra- and extracellular functions.

  11. Directly transforming PCR-amplified DNA fragments into plant cells is a versatile system that facilitates the transient expression assay.

    PubMed

    Lu, Yuming; Chen, Xi; Wu, Yuxuan; Wang, Yanping; He, Yuqing; Wu, Yan

    2013-01-01

    A circular plasmid containing a gene coding sequence has been broadly used for studying gene regulation in cells. However, to accommodate a quick screen plasmid construction and preparation can be time consuming. Here we report a PCR amplified dsDNA fragments (PCR-fragments) based transient expression system (PCR-TES) for suiting in the study of gene regulation in plant cells. Instead of transforming plasmids into plant cells, transient expression of PCR-fragments can be applicable. The transformation efficiency and expression property of PCR-fragments are comparable to transformation using plasmids. We analyzed the transformation efficiency in PCR-TES at transcription and protein levels. Our results indicate that the PCR-TES is as versatile as the conventional transformation system using plasmid DNA. Through reconstituting PYR1-mediated ABA signaling pathway in Arabidopsis mesophyll protoplasts, we were not only validating the practicality of PCR-TES but also screening potential candidates of CDPK family members which might be involved in the ABA signaling. Moreover, we determined that phosphorylation of ABF2 by CPK4 could be mediated by ABA-induced PYR1 and ABI1, demonstrating a crucial role of CDPKs in the ABA signaling. In summary, PCR-TES can be applicable to facilitate analyzing gene regulation and for the screen of putative regulatory molecules at the high throughput level in plant cells.

  12. Spatially and temporally restricted expression of PtrMYB021 regulates secondary cell wall formation in Arabidopsis

    DOE PAGES

    Wang, Wei; Li, Eryang; Porth, Ilga; ...

    2016-02-02

    Among the R2R3 MYB transcription factors that involve in the regulation of secondary cell wall formation in Arabidopsis, MYB46 alone is sufficient to induce the entire secondary cell wall biosynthesis program. PtrMYB021, the poplar homolog of MYB46, has been reported to regulate secondary cell wall formation when expressed in Arabidopsis. We report here that spatially and temporally restricted expression of PtrMYB021 is critical for its function in regulating secondary cell wall formation. By using quantitative RT-PCR, we found that PtrMYB021 was expressed primarily in xylem tissues. When expressed in Arabidopsis under the control of PtrCesA8, but not the 35S promoter,more » PtrMYB021 increased secondary cell wall thickness, which is likely caused by increased lignification as well as changes in cell wall carbohydrate composition. Consistent with this, elevated expression of lignin and cellulose biosynthetic genes were observed in the transgenic plants. Finally, when expressed in Arabidopsis protoplasts as fusion proteins to the Gal4 DNA binding domain, PtrMYB021 activated the reporter gene Gal4-GUS. In summary, our results suggest that PtrMYB021 is a transcriptional activator, and spatially and temporally restricted expression of PtrMYB021 in Arabidopsis regulates secondary cell wall formation by activating a subset of secondary cell wall biosynthesis genes.« less

  13. Spatially and temporally restricted expression of PtrMYB021 regulates secondary cell wall formation in Arabidopsis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wang, Wei; Li, Eryang; Porth, Ilga

    Among the R2R3 MYB transcription factors that involve in the regulation of secondary cell wall formation in Arabidopsis, MYB46 alone is sufficient to induce the entire secondary cell wall biosynthesis program. PtrMYB021, the poplar homolog of MYB46, has been reported to regulate secondary cell wall formation when expressed in Arabidopsis. We report here that spatially and temporally restricted expression of PtrMYB021 is critical for its function in regulating secondary cell wall formation. By using quantitative RT-PCR, we found that PtrMYB021 was expressed primarily in xylem tissues. When expressed in Arabidopsis under the control of PtrCesA8, but not the 35S promoter,more » PtrMYB021 increased secondary cell wall thickness, which is likely caused by increased lignification as well as changes in cell wall carbohydrate composition. Consistent with this, elevated expression of lignin and cellulose biosynthetic genes were observed in the transgenic plants. Finally, when expressed in Arabidopsis protoplasts as fusion proteins to the Gal4 DNA binding domain, PtrMYB021 activated the reporter gene Gal4-GUS. In summary, our results suggest that PtrMYB021 is a transcriptional activator, and spatially and temporally restricted expression of PtrMYB021 in Arabidopsis regulates secondary cell wall formation by activating a subset of secondary cell wall biosynthesis genes.« less

  14. Directly Transforming PCR-Amplified DNA Fragments into Plant Cells Is a Versatile System That Facilitates the Transient Expression Assay

    PubMed Central

    Lu, Yuming; Chen, Xi; Wu, Yuxuan; Wang, Yanping; He, Yuqing; Wu, Yan

    2013-01-01

    A circular plasmid containing a gene coding sequence has been broadly used for studying gene regulation in cells. However, to accommodate a quick screen plasmid construction and preparation can be time consuming. Here we report a PCR amplified dsDNA fragments (PCR-fragments) based transient expression system (PCR-TES) for suiting in the study of gene regulation in plant cells. Instead of transforming plasmids into plant cells, transient expression of PCR-fragments can be applicable. The transformation efficiency and expression property of PCR-fragments are comparable to transformation using plasmids. We analyzed the transformation efficiency in PCR-TES at transcription and protein levels. Our results indicate that the PCR-TES is as versatile as the conventional transformation system using plasmid DNA. Through reconstituting PYR1-mediated ABA signaling pathway in Arabidopsis mesophyll protoplasts, we were not only validating the practicality of PCR-TES but also screening potential candidates of CDPK family members which might be involved in the ABA signaling. Moreover, we determined that phosphorylation of ABF2 by CPK4 could be mediated by ABA-induced PYR1 and ABI1, demonstrating a crucial role of CDPKs in the ABA signaling. In summary, PCR-TES can be applicable to facilitate analyzing gene regulation and for the screen of putative regulatory molecules at the high throughput level in plant cells. PMID:23468926

  15. Deficiencies in FY 1998 DOD Financial Statements and Progress Toward Improved Financial Reporting

    DTIC Science & Technology

    1999-11-26

    DEFICIENCIES IN FY 1998 DOD FINANCIAL STATEMENTS AND PROGRESS TOWARD IMPROVED FINANCIAL REPORTING Report No. D-2000-041 November 26, 1999 Office... Financial Reporting (Report No. D-2000-041) We are providing this audit report for information and use. It identifies and summarizes the major...8FI-2025.02) Deficiencies in FY 1998 DoD Financial Statements and Progress Toward Improved Financial Reporting Executive Summary Introduction

  16. Measuring disease progression in early Parkinson disease: the National Institutes of Health Exploratory Trials in Parkinson Disease (NET-PD) experience.

    PubMed

    Parashos, Sotirios A; Luo, Sheng; Biglan, Kevin M; Bodis-Wollner, Ivan; He, Bo; Liang, Grace S; Ross, G Webster; Tilley, Barbara C; Shulman, Lisa M

    2014-06-01

    Optimizing assessments of rate of progression in Parkinson disease (PD) is important in designing clinical trials, especially of potential disease-modifying agents. To examine the value of measures of impairment, disability, and quality of life in assessing progression in early PD. Inception cohort analysis of data from 413 patients with early, untreated PD who were enrolled in 2 multicenter, randomized, double-blind clinical trials. Participants were randomly assigned to 1 of 5 treatments (67 received creatine, 66 received minocycline, 71 received coenzyme Q10, 71 received GPI-1485, and 138 received placebo). We assessed the association between the rates of change in measures of impairment, disability, and quality of life and time to initiation of symptomatic treatment. Time between baseline assessment and need for the initiation of symptomatic pharmaceutical treatment for PD was the primary indicator of disease progression. After adjusting for baseline confounding variables with regard to the Unified Parkinson's Disease Rating Scale (UPDRS) Part II score, the UPDRS Part III score, the modified Rankin Scale score, level of education, and treatment group, we assessed the rate of change for the following measurements: the UPDRS Part II score; the UPDRS Part III score; the Schwab and England Independence Scale score (which measures activities of daily living); the Total Functional Capacity scale; the 39-item Parkinson's Disease Questionnaire, summary index, and activities of daily living subscale; and version 2 of the 12-item Short Form Health Survey Physical Summary and Mental Summary. Variables reaching the statistical threshold in univariate analysis were entered into a multivariable Cox proportional hazards model using time to symptomatic treatment as the dependent variable. More rapid change (ie, worsening) in the UPDRS Part II score (hazard ratio, 1.15 [95% CI, 1.08-1.22] for 1 scale unit change per 6 months), the UPDRS Part III score (hazard ratio, 1.09 [95% CI, 1.06-1.13] for 1 scale unit change per 6 months), and the Schwab and England Independence Scale score (hazard ratio, 1.29 [95% CI, 1.12-1.48] for 5 percentage point change per 6 months) was associated with earlier need for symptomatic therapy. AND RELEVANCE In early PD, the UPDRS Part II score and Part III score and the Schwab and England Independence Scale score can be used to measure disease progression, whereas the 39-item Parkinson's Disease Questionnaire and summary index, Total Functional Capacity scale, and the 12-item Short Form Health Survey Physical Summary and Mental Summary are not sensitive to change. clinicaltrials.gov Identifiers: NCT00063193 and NCT00076492.

  17. The Grid Analysis and Display System (GrADS)

    NASA Technical Reports Server (NTRS)

    Kinter, James L., III

    1994-01-01

    During the period 1 September 1993 - 31 August 1994, further development of the Grid Analysis and Display System (GrADS) was conducted at the Center for Ocean-Land-Atmosphere Studies (COLA) of the Institute of Global Environment and Society, Inc. (IGES) under subcontract 5555-31 from the University Space Research Association (USRA) administered by The Center of Excellence in Space Data and Information Sciences (CESDIS). This final report documents progress made under this subcontract and provides directions on how to access the software and documentation developed therein. A short description of GrADS is provided followed by summary of progress completed and a summary of the distribution of the software to date and the establishment of research collaborations.

  18. SCES2016 Summary: Experiment

    DOE PAGES

    Thompson, Joe David

    2016-08-03

    Experimental results presented during the 2016 International Conference on Strongly Correlated Electron Systems (SECS2016) not only reflect the breadth of topics being explored in the field of strongly correlated systems but also the remarkable progress in discovery and understanding that is being made from their study. Lastly, this brief summary highlights just a few of the exciting experimental developments discussed at SCES2016.

  19. Race to the Top. Hawaii Report. Year 4: School Year 2013-2014. [State-Specific Summary Report

    ERIC Educational Resources Information Center

    US Department of Education, 2015

    2015-01-01

    This State-specific summary report serves as an assessment of Hawaii's Year 4 Race to the Top implementation. Hawaii made tremendous progress over the course of the grant period in implementing its Strategic Plan and six priority strategies and creating an aligned organization focused on increasing student outcomes. Among some of the other…

  20. Research and Technology Objectives and Plans Summary (RTOPS)

    NASA Technical Reports Server (NTRS)

    1992-01-01

    This publication represents the NASA research and technology program for FY92. It is a compilation of the Summary portions of each of the RTOP's (Research and Technology Objectives and Plans) used for management review and control of research currently in progress throughout NASA. The RTOP Summary is designed to facilitate communication and coordination among concerned technical personnel in government, in industry, and in universities. The first section containing citations and abstracts of the RTOP's is followed by four indexes: Subject, Technical Monitor, Responsible NASA Organization, and RTOP Number.

  1. Research and technology objectives and plans: Summary fiscal year 1991

    NASA Technical Reports Server (NTRS)

    1991-01-01

    This publication represents the NASA research and technology program for FY 1991. It is a compilation of the Summary portions of each of the RTOP's (Research and Technology Objectives and Plans) used for management review and control of research currently in progress throughout NASA. The RTOP Summary is designed to facilitate communication and coordination among concerned technical personnel in government, industry, and in universities. The first section contains citations and abstracts of the RTOP's and is followed by four indexes: Subject, Technical Monitor, Responsible NASA Organization, and RTOP Number.

  2. Research and Technology Objectives and Plans Summary (RTOPS)

    NASA Technical Reports Server (NTRS)

    1993-01-01

    This publication represents the NASA research and technology program for FY-93. It is a compilation of the Summary portions of each of the RTOP's (Research and Technology Objectives and Plans) used for management review and control of research currently in progress throughout NASA. The RTOP Summary is designed to facilitate communication and coordination among concerned technical personnel in government, in industry, and in universities. The first section containing citations and abstracts of the RTOP's is followed by four indexes: Subject, Technical Monitor, Responsible NASA Organization, and RTOP Number.

  3. Research and Technology Objectives and Plans Summary (RTOPS)

    NASA Technical Reports Server (NTRS)

    1988-01-01

    This publication represents the NASA research and technology program for FY88. It is a compilation of the Summary portions of each of the RTOPs (Research and Technology Objectives and Plans) used for management review and control of research currently in progress throughout NASA. The RTOP Summary is designed to facilitate communication and coordination among concerned technical personnel in government, in industry, and in universities. The first section containing citations and abstracts of the RTOPs is followed by four indexes: Subject, Technical Monitor, Responsible NASA Organization, and RTOP Number.

  4. Research and Technology Objectives and Plans Summary (RTOPS)

    NASA Technical Reports Server (NTRS)

    1989-01-01

    This publication represents the NASA research and technology program for FY89. It is a compilation of the Summary portions of each of the RTOPs (Research and Technology Objectives and Plans) used for management review and control of research currently in progress throughout NASA. The RTOP Summary is designed to facilitate communication and coordination among concerned technical personnel in government, in industry, and in universities. The first section containing citations and abstracts of the RTOPs is followed by four indexes: Subject, Technical Monitor, Responsible NASA Organization, and RTOP Number.

  5. Research and Technology Objectives and Plans Summary (RTOPS)

    NASA Technical Reports Server (NTRS)

    1985-01-01

    This publication represents the NASA research and technology program for FY 1985. It is a compilation of the Summary portions of each of the RTOPs (Research and Technology Objectives and Plans) used for management review and control of research currently in progress throughout NASA. The RTOP summary is designed to facilitate communication and coordination among concerned technical personnel in government, in industry, and in universities. The first section containing citations and abstracts of the RTOPs is followed by four indexes: Subject, Technical Monitor, Responsible NASA Organization, and RTOP number.

  6. Research and Technology Objectives and Plans Summary (RTOPS)

    NASA Technical Reports Server (NTRS)

    1987-01-01

    This publication represents the NASA research and technology program for FY87. It is a compilation of the Summary portions of each of the RTOPs (Research and Technology Objectives and Plans) used for management review and control of research currently in progress throughout NASA. The RTOP Summary is designed to facilitate communication and coordination among concerned technical personnel in government, in industry, and in universities. The first section containing citations and abstracts of the RTOPs is followed by four indexes: Subject, Technical Monitor, Responsible NASA Organization, and RTOP Number.

  7. Predictors and Outcomes of Health–Related Quality of Life in Adults with CKD

    PubMed Central

    Lash, James P.; Xie, Dawei; Pan, Qiang; DeLuca, Jennifer; Kanthety, Radhika; Kusek, John W.; Lora, Claudia M.; Nessel, Lisa; Ricardo, Ana C.; Wright Nunes, Julie; Fischer, Michael J.

    2016-01-01

    Background and objectives Low health–related quality of life is associated with increased mortality in patients with ESRD. However, little is known about demographic and clinical factors associated with health–related quality of life or its effect on outcomes in adults with CKD. Design, settings, participants, & measurements Data from 3837 adult participants with mild to severe CKD enrolled in the prospective observational Chronic Renal Insufficiency Cohort and Hispanic Chronic Renal Insufficiency Cohort Studies were analyzed. Health–related quality of life was assessed at baseline with the Kidney Disease Quality of Life-36 and its five subscales: mental component summary, physical component summary, burden of kidney disease (burden), effects of kidney disease (effects), and symptoms and problems of kidney disease (symptoms). Low health–related quality of life was defined as baseline score >1 SD below the mean. Using Cox proportional hazards analysis, the relationships between low health–related quality of life and the following outcomes were examined: (1) CKD progression (50% eGFR loss or incident ESRD), (2) incident cardiovascular events, and (3) all-cause death. Results Younger age, women, low education, diabetes, vascular disease, congestive heart failure, obesity, and lower eGFR were associated with low baseline health–related quality of life (P<0.05). During a median follow-up of 6.2 years, there were 1055 CKD progression events, 841 cardiovascular events, and 694 deaths. Significantly higher crude rates of CKD progression, incident cardiovascular events, and all-cause death were observed among participants with low health–related quality of life in all subscales (P<0.05). In fully adjusted models, low physical component summary, effects, and symptoms subscales were independently associated with a higher risk of incident cardiovascular events and death, whereas low mental component summary was independently associated with a higher risk of death (P<0.05). Low health–related quality of life was not associated with CKD progression. Conclusions Low health–related quality of life across several subscales was independently associated with a higher risk of incident cardiovascular events and death but not associated with CKD progression. PMID:27246012

  8. Development and operations of the astrophysics data system

    NASA Technical Reports Server (NTRS)

    Murray, S. S.

    1996-01-01

    Monthly progress reports are given for the period April 1994 through September 1994. Each month's progress includes a general summary and overviews of Administrative functions, Systems Engineering, User Committee, User Support, Test and QA, System Integration, Development, Operations, and Suppliers of Data. These overviews include user and query statistics for the month.

  9. Steering Committee Progress Report on Hydrogen Sensor Performance Testing and Evaluation under the Memorandum of Agreement between NREL, U.S. DOE and JRC-IET, EC

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Buttner, W.; Post, M.; Burgess, R.

    This progress report is a programmatic summary of a formal MOA between NREL and the European Union Joint Research Center, Institute for Energy and Transport to be presented at the Steering Committee Meeting, December 3, 2012.

  10. Progress Report on Rural Development for Fiscal Year 1970.

    ERIC Educational Resources Information Center

    Department of Agriculture, Washington, DC.

    Rural development progress relative to State-U.S. Department of Agriculture (USDA) committees is presented via exemplary citation in this 1970 report. Summaries are given for: (1) Status of State-USDA Organization for Rural Development, (2) Functional Relationships of USDA Committees on Rural Development, (3) Activities and Projects Underway, (4)…

  11. Development and operations of the astrophysics data system

    NASA Technical Reports Server (NTRS)

    Murray, S. S.

    1996-01-01

    Monthly progress reports are given for the period October 1993 through March 1994. Each month's progress includes a general summary and overviews of Administrative functions, Systems Engineering, User Committee, User Support, Test and QA, System Integration, Development, Operations, and Suppliers of Data. These overviews include user and query statistics for the month.

  12. Gravisensing in roots

    NASA Astrophysics Data System (ADS)

    Perbal, G.

    1999-01-01

    The mode of gravisensing in higher plants is not yet elucidated. Although, it is generally accepted that the amyloplasts (statoliths) in the root cap cells (statocytes) are responsible for susception of gravity. However, the hypothesis that the whole protoplast acts as gravisusceptor cannot be dismissed. The nature of the sensor that is able to transduce and amplify the mechanical energy into a biochemical factor is even more controversial. Several cell structures could potentially serve as gravireceptors: the endoplasmic reticulum, the actin network, the plasma membrane, or the cytoskeleton associated with this membrane. The nature of the gravisusceptors and gravisensors is discussed by taking into account the characteristics of the gravitropic reaction with respect to the presentation time, the threshold acceleration, the reciprocity rule, the deviation from the sine rule, the movement of the amyloplasts, the pre-inversion effect, the response of starch free and intermediate mutants and the effects of cytochalasin treatment. From this analysis, it can be concluded that both the amyloplasts and the protoplast could be the gravisusceptors, the former being more efficient than the latter since they can focus pressure on limited areas. The receptor should be located in the plasma membrane and could be a stretch-activated ion channel.

  13. [Comparisons of different methods for virus-elimination of edible fungi].

    PubMed

    Zhang, Chao-hui; Liu, Ying-miao; Qi, Yuan-cheng; Gao, Yu-qian; Shen, Jin-wen; Qiu, Li-you

    2010-05-01

    Four dsRNA bands were extracted from Pleurotus ostreatus TD300 by the dsRNA isolation technique with sizes of 8.2 kb, 2.5 kb, 2.1 kb, and 1.1 kb, respectively. Four virus-eliminated methods, i. e. hyphal tips cut (HTC), protoplast regeneration (PR), single spore hybridization (SSH), and frozen and lyophilized (FL), were applied to prepare virus-eliminated strains, and one virus-eliminated strain was selected for each virus-elimination method. The virus-eliminated strains were named as HTC8, PR15, FL01, and SSH11, respectively. There were low concentration of 8.2 kb dsRNA remained in HTC8, as well as low concentration of 8.2 kb and 2.5 kb dsRNA remained in FL01. However, no dsRNA remained in PR15 and SSH11. The hyphal growth rate and laccase activity of the virus-eliminated strains increased, especially HTC8 and PR15, whose hyphal growth rate was higher by 22.73% and 18.18%, and laccase activities higher by 145.83% and 134.38% than that of the original strain, respectively. The conclusion is that hyphal tips cut and protoplast regeneration are suitable to prepare virus-eliminated strains of edible fungi.

  14. Isolation and properties of mesosomal membrane fractions from Micrococcus lysodeikticus

    PubMed Central

    Owen, Peter; Freer, John H.

    1972-01-01

    1. A method is described for the isolation of pure mesosomal membrane fractions from Micrococcus lysodeikticus. 2. Plasmolysis of cells, before wall digestion, was necessary for effective mesosome release. 3. The effect of mild shearing forces, temperature and time upon the release of mesosomal membrane from protoplasts was investigated. 4. The optimum yield of mesosomal membranes from stable protoplasts was achieved at 10mm-Mg2+. 5. Mesosomal membrane vesicle fractions prepared at differing Mg2+ concentrations above 10mm were similar in chemical composition. 6. Comparison of the properties of peripheral and mesosomal membrane fractions revealed major differences in the distribution of protein components, membrane phosphorus, mannose and dehydrogenase activities between the two fractions. 7. Only cytochrome b556 was detected in mesosomal membranes, whereas peripheral membranes contained a full complement of cytochromes. 8. Preliminary investigations suggested the localization of an autolytic enzyme(s) in the mesosomal vesicles. 9. The anatomy of mesosomal and peripheral membrane have been compared by the negative-staining and freeze-fracture technique. 10. The results are discussed in relation to a plausible role for the mesosome. ImagesPLATE 1PLATE 2PLATE 3PLATE 4 PMID:4655825

  15. Function of Oxidative Cross-Linking of Cell Wall Structural Proteins in Plant Disease Resistance.

    PubMed

    Brisson, L. F.; Tenhaken, R.; Lamb, C.

    1994-12-01

    Elicitation of soybean cells causes a rapid insolubilization of two cell wall structural proteins, p33 and p100. Likewise, a short elicitation of 30 min rendered cell walls more refractory to enzyme digestion as assayed by the yield of protoplasts released. This effect could be ascribed to protein cross-linking because of its insensitivity to inhibitors of transcription (actinomycin D) and translation (cycloheximide) and its induction by exogenous H2O2. Moreover, the induced loss of protoplasts could be prevented by preincubation with DTT, which also blocks peroxidase-mediated oxidative cross-linking. The operation of protein insolubilization in plant defense was also demonstrated by its occurrence in the incompatible interaction but not in the compatible interaction between soybean and Pseudomonas syringae pv glycinea. Likewise, protein insolubilization was observed in bean during non-host hypersensitive resistance to the tobacco pathogen P. s. pv tabaci mediated by the hypersensitive resistance and pathogenicity (Hrp) gene cluster. Our data strongly suggest that rapid protein insolubilization leads to a strengthened cell wall, and this mechanism functions as a rapid defense in the initial stages of the hypersensitive response prior to deployment of transcription-dependent defenses.

  16. A rapid, highly efficient and economical method of Agrobacterium-mediated in planta transient transformation in living onion epidermis.

    PubMed

    Xu, Kedong; Huang, Xiaohui; Wu, Manman; Wang, Yan; Chang, Yunxia; Liu, Kun; Zhang, Ju; Zhang, Yi; Zhang, Fuli; Yi, Liming; Li, Tingting; Wang, Ruiyue; Tan, Guangxuan; Li, Chengwei

    2014-01-01

    Transient transformation is simpler, more efficient and economical in analyzing protein subcellular localization than stable transformation. Fluorescent fusion proteins were often used in transient transformation to follow the in vivo behavior of proteins. Onion epidermis, which has large, living and transparent cells in a monolayer, is suitable to visualize fluorescent fusion proteins. The often used transient transformation methods included particle bombardment, protoplast transfection and Agrobacterium-mediated transformation. Particle bombardment in onion epidermis was successfully established, however, it was expensive, biolistic equipment dependent and with low transformation efficiency. We developed a highly efficient in planta transient transformation method in onion epidermis by using a special agroinfiltration method, which could be fulfilled within 5 days from the pretreatment of onion bulb to the best time-point for analyzing gene expression. The transformation conditions were optimized to achieve 43.87% transformation efficiency in living onion epidermis. The developed method has advantages in cost, time-consuming, equipment dependency and transformation efficiency in contrast with those methods of particle bombardment in onion epidermal cells, protoplast transfection and Agrobacterium-mediated transient transformation in leaf epidermal cells of other plants. It will facilitate the analysis of protein subcellular localization on a large scale.

  17. Detection of Oil Palm Root Penetration by Agrobacterium-Mediated Transformed Ganoderma boninense, Expressing Green Fluorescent Protein.

    PubMed

    Govender, Nisha; Wong, Mui-Yun

    2017-04-01

    A highly efficient and reproducible Agrobacterium-mediated transformation protocol for Ganoderma boninense was developed to facilitate observation of the early stage infection of basal stem rot (BSR). The method was proven amenable to different explants (basidiospore, protoplast, and mycelium) of G. boninense. The transformation efficiency was highest (62%) under a treatment combination of protoplast explant and Agrobacterium strain LBA4404, with successful expression of an hyg marker gene and gus-gfp fusion gene under the control of heterologous p416 glyceraldehyde 3-phosphate dehydrogenase promoter. Optimal transformation conditions included a 1:100 Agrobacterium/explant ratio, induction of Agrobacterium virulence genes in the presence of 250 μm acetosyringone, co-cultivation at 22°C for 2 days on nitrocellulose membrane overlaid on an induction medium, and regeneration of transformants on potato glucose agar prepared with 0.6 M sucrose and 20 mM phosphate buffer. Evaluated transformants were able to infect root tissues of oil palm plantlets with needle-like microhyphae during the penetration event. The availability of this model pathogen system for BSR may lead to a better understanding of the pathogenicity factors associated with G. boninense penetration into oil palm roots.

  18. Photoprotection by foliar anthocyanins mitigates effects of boron toxicity in sweet basil (Ocimum basilicum).

    PubMed

    Landi, Marco; Guidi, Lucia; Pardossi, Alberto; Tattini, Massimiliano; Gould, Kevin S

    2014-11-01

    Boron (B) toxicity is an important agricultural problem in arid environments. Excess edaphic B compromises photosynthetic efficiency, limits growth and reduces crop yield. However, some purple-leafed cultivars of sweet basil (Ocimum basilicum) exhibit greater tolerance to high B concentrations than do green-leafed cultivars. We hypothesised that foliar anthocyanins protect basil leaf mesophyll from photo-oxidative stress when chloroplast function is compromised by B toxicity. Purple-leafed 'Red Rubin' and green-leafed 'Tigullio' cultivars, grown with high or negligible edaphic B, were given a photoinhibitory light treatment. Possible effects of photoabatement by anthocyanins were simulated by superimposing a purple polycarbonate filter on the green leaves. An ameliorative effect of light filtering on photosynthetic quantum yield and on photo-oxidative load was observed in B-stressed plants. In addition, when green protoplasts from both cultivars were treated with B and illuminated through a screen of anthocyanic protoplasts or a polycarbonate film which approximated cyanidin-3-O-glucoside optical properties, the degree of photoinhibition, hydrogen peroxide production, and malondialdehyde content were reduced. The data provide evidence that anthocyanins exert a photoprotective role in purple-leafed basil mesophyll cells, thereby contributing to improved tolerance to high B concentrations.

  19. Is the virulence of HIV changing? A meta-analysis of trends in prognostic markers of HIV disease progression and transmission

    PubMed Central

    Herbeck, Joshua T.; Müller, Viktor; Maust, Brandon S.; Ledergerber, Bruno; Torti, Carlo; Di Giambenedetto, Simona; Gras, Luuk; Günthard, Huldrych F.; Jacobson, Lisa P.; Mullins, James I.; Gottlieb, Geoffrey S.

    2013-01-01

    Objective The potential for changing HIV-1 virulence has significant implications for the AIDS epidemic, including changing HIV transmission rates, rapidity of disease progression, and timing of ART. Published data to date have provided conflicting results. Design We conducted a meta-analysis of changes in baseline CD4+ T-cell counts and set point plasma viral RNA load over time in order to establish whether summary trends are consistent with changing HIV-1 virulence. Methods We searched PubMed for studies of trends in HIV-1 prognostic markers of disease progression and supplemented findings with publications referenced in epidemiological or virulence studies. We identified 12 studies of trends in baseline CD4+ T-cell counts (21 052 total individuals), and eight studies of trends in set point viral loads (10 785 total individuals), spanning the years 1984–2010. Using random-effects meta-analysis, we estimated summary effect sizes for trends in HIV-1 plasma viral loads and CD4+ T-cell counts. Results Baseline CD4+ T-cell counts showed a summary trend of decreasing cell counts [effect=−4.93 cells/µl per year, 95% confidence interval (CI) −6.53 to −3.3]. Set point viral loads showed a summary trend of increasing plasma viral RNA loads (effect=0.013 log10 copies/ml per year, 95% CI −0.001 to 0.03). The trend rates decelerated in recent years for both prognostic markers. Conclusion Our results are consistent with increased virulence of HIV-1 over the course of the epidemic. Extrapolating over the 30 years since the first description of AIDS, this represents a CD4+ T cells loss of approximately 148 cells/µl and a gain of 0.39 log10 copies/ml of viral RNA measured during early infection. These effect sizes would predict increasing rates of disease progression, and need for ART as well as increasing transmission risk. PMID:22089381

  20. The deep space network

    NASA Technical Reports Server (NTRS)

    1975-01-01

    Summaries are given of Deep Space Network progress in flight project support, tracking and data acquisition research and technology, network engineering, hardware and software implementation, and operations.

  1. Where the Girls Are: The Facts about Gender Equity in Education. Executive Summary

    ERIC Educational Resources Information Center

    Corbett, Christianne; Hill, Catherine; St. Rose, Andresse

    2008-01-01

    This document summarizes the full report, which presents a comprehensive look at girls' educational achievement during the past 35 years, paying special attention to the relationship between girls' and boys' progress. Analyses of results from national standardized tests such as the National Assessment of Educational Progress (NAEP) and the SAT and…

  2. Putting Children First: A Progressive Family Policy for the 1990s.

    ERIC Educational Resources Information Center

    Kamarck, Elaine Ciulla; Galston, William A.

    Four policy papers delineate a progressive family policy for the 1990s that makes the family central among social issues and children central in families. An extensive introduction delineates the split between leaders' and ordinary citizens' views on the family and provides a summary of the papers. The first paper offers an economic review of the…

  3. The Resource-Infrastructure-Environment Index for Measuring Progress: An Application to Australia, Mexico and the US

    ERIC Educational Resources Information Center

    Natoli, Riccardo; Zuhair, Segu

    2013-01-01

    The resource-infrastructure-environment (RIE) index was proposed as an alternative measure of progress which was then employed to: (1) compare the aggregate (single summary) index findings between Australia (mid-industrialised nation), Mexico (emerging economy), and the US (highly industrialised nation); and (2) compare the RIE index against the…

  4. Research And Development Contributions to Aviation Progress (RADCAP): Executive summary

    NASA Technical Reports Server (NTRS)

    1972-01-01

    Positive contributions of military aeronautical research and development programs to civil aviation are reviewed and some possible future contributions of those military programs are assessed. A summary is presented of detailed results concerned with: (1) review of the progress that has been made in aviation since 1925 and the significant technological advances that have been made; (2) an examination of current and planned military aeronautical research and technology programs and an assessment of their relevancy to the aeronautical R and D needs of civil aviation; (3) the relationship of the development base generated by military programs to the needs of civil airliner design, development, and production; (4) information on aeronautical R and D funding; and (5) the findings and observations of the RADCAP study.

  5. Dissecting the genetics of complex traits using summary association statistics.

    PubMed

    Pasaniuc, Bogdan; Price, Alkes L

    2017-02-01

    During the past decade, genome-wide association studies (GWAS) have been used to successfully identify tens of thousands of genetic variants associated with complex traits and diseases. These studies have produced extensive repositories of genetic variation and trait measurements across large numbers of individuals, providing tremendous opportunities for further analyses. However, privacy concerns and other logistical considerations often limit access to individual-level genetic data, motivating the development of methods that analyse summary association statistics. Here, we review recent progress on statistical methods that leverage summary association data to gain insights into the genetic basis of complex traits and diseases.

  6. Dissecting the genetics of complex traits using summary association statistics

    PubMed Central

    Pasaniuc, Bogdan; Price, Alkes L.

    2017-01-01

    During the past decade, genome-wide association studies (GWAS) have successfully identified tens of thousands of genetic variants associated with complex traits and diseases. These studies have produced extensive repositories of genetic variation and trait measurements across large numbers of individuals, providing tremendous opportunities for further analyses. However, privacy concerns and other logistical considerations often limit access to individual-level genetic data, motivating the development of methods that analyze summary association statistics. Here we review recent progress on statistical methods that leverage summary association data to gain insights into the genetic basis of complex traits and diseases. PMID:27840428

  7. Multi-Photon Micro-Spectroscopy of Biological Specimens

    DTIC Science & Technology

    2000-07-01

    Micro-spectroscopy, multi-photon fluorescence spectroscopy, second harmonic generation, plant tissues, stem, chloroplast, protoplast, maize, Arabidopsis...harmonic generation (SHG) in the plant cell 5wall. In this case, micro-spectroscopy provides a means of verification that, indeed, SHG occurs in plant ...fluorescence microscopy -the response of plant cells to high intensity illumination," Micron (in press) 2000. 3. H.-C. Huang and C. -C Chen, "Genome

  8. Protoplast-Esculin Assay as a New Method to Assay Plant Sucrose Transporters: Characterization of AtSUC6 and AtSUC7 Sucrose Uptake Activity in Arabidopsis Col-0 Ecotype.

    PubMed

    Rottmann, Theresa M; Fritz, Carolin; Lauter, Anja; Schneider, Sabine; Fischer, Cornelia; Danzberger, Nina; Dietrich, Petra; Sauer, Norbert; Stadler, Ruth

    2018-01-01

    The best characterized function of sucrose transporters of the SUC family in plants is the uptake of sucrose into the phloem for long-distance transport of photoassimilates. This important step is usually performed by one specific SUC in every species. However, plants possess small families of several different SUCs which are less well understood. Here, we report on the characterization of AtSUC6 and AtSUC7, two members of the SUC family in Arabidopsis thaliana . Heterologous expression in yeast ( Saccharomyces cerevisiae ) revealed that AtSUC6 Col-0 is a high-affinity H + -symporter that mediates the uptake of sucrose and maltose across the plasma membrane at exceptionally low pH values. Reporter gene analyses revealed a strong expression of AtSUC6 Col-0 in reproductive tissues, where the protein product might contribute to sugar uptake into pollen tubes and synergid cells. A knockout of AtSUC6 did not interfere with vegetative development or reproduction, which points toward physiological redundancy of AtSUC6 Col-0 with other sugar transporters. Reporter gene analyses showed that AtSUC7 Col-0 is expressed in roots and pollen tubes and that this sink specific expression of AtSUC7 Col-0 is regulated by intragenic regions. Transport activity of AtSUC7 Col-0 could not be analyzed in baker's yeast or Xenopus oocytes because the protein was not correctly targeted to the plasma membrane in both heterologous expression systems. Therefore, a novel approach to analyze sucrose transporters in planta was developed. Plasma membrane localized SUCs including AtSUC6 Col-0 and also sucrose specific SWEETs were able to mediate transport of the fluorescent sucrose analog esculin in transformed mesophyll protoplasts. In contrast, AtSUC7 Col-0 is not able to mediate esculin transport across the plasma membrane which implicates that AtSUC7 Col-0 might be a non-functional pseudogene. The novel protoplast assay provides a useful tool for the quick and quantitative analysis of sucrose transporters in an in planta expression system.

  9. Protoplast-Esculin Assay as a New Method to Assay Plant Sucrose Transporters: Characterization of AtSUC6 and AtSUC7 Sucrose Uptake Activity in Arabidopsis Col-0 Ecotype

    PubMed Central

    Rottmann, Theresa M.; Fritz, Carolin; Lauter, Anja; Schneider, Sabine; Fischer, Cornelia; Danzberger, Nina; Dietrich, Petra; Sauer, Norbert; Stadler, Ruth

    2018-01-01

    The best characterized function of sucrose transporters of the SUC family in plants is the uptake of sucrose into the phloem for long-distance transport of photoassimilates. This important step is usually performed by one specific SUC in every species. However, plants possess small families of several different SUCs which are less well understood. Here, we report on the characterization of AtSUC6 and AtSUC7, two members of the SUC family in Arabidopsis thaliana. Heterologous expression in yeast (Saccharomyces cerevisiae) revealed that AtSUC6Col-0 is a high-affinity H+-symporter that mediates the uptake of sucrose and maltose across the plasma membrane at exceptionally low pH values. Reporter gene analyses revealed a strong expression of AtSUC6Col-0 in reproductive tissues, where the protein product might contribute to sugar uptake into pollen tubes and synergid cells. A knockout of AtSUC6 did not interfere with vegetative development or reproduction, which points toward physiological redundancy of AtSUC6Col-0 with other sugar transporters. Reporter gene analyses showed that AtSUC7Col-0 is expressed in roots and pollen tubes and that this sink specific expression of AtSUC7Col-0 is regulated by intragenic regions. Transport activity of AtSUC7Col-0 could not be analyzed in baker’s yeast or Xenopus oocytes because the protein was not correctly targeted to the plasma membrane in both heterologous expression systems. Therefore, a novel approach to analyze sucrose transporters in planta was developed. Plasma membrane localized SUCs including AtSUC6Col-0 and also sucrose specific SWEETs were able to mediate transport of the fluorescent sucrose analog esculin in transformed mesophyll protoplasts. In contrast, AtSUC7Col-0 is not able to mediate esculin transport across the plasma membrane which implicates that AtSUC7Col-0 might be a non-functional pseudogene. The novel protoplast assay provides a useful tool for the quick and quantitative analysis of sucrose transporters in an in planta expression system. PMID:29740457

  10. Membrane Asymmetry and Expression of Cell Surface Antigens of Micrococcus lysodeikticus Established by Crossed Immunoelectrophoresis

    PubMed Central

    Owen, Peter; Salton, Milton R. J.

    1977-01-01

    Crossed immunoelectrophoresis of Triton X-100-solubilized plasma membranes of Micrococcus lysodeikticus established the presence of 27 discrete antigens. Individual antigens were identified as membrane components possessing enzyme activity by zymogram staining procedures and by reactivity of certain antigens with a selection of four lectins in the crossed-immunoelectrophoresis (immunoaffinoelectrophoresis) system. Absorption experiments with intact, stable protoplasts and isolated membranes established the asymmetric nature of the M. lysodeikticus plasma membranes. Of the 14 antigens with determinants accessible solely on the cytoplasmic face of the membrane, four possessed individual dehydrogenase activities, and a fifth was identifiable as a component possessing adenosine triphosphatase (EC 3.6.1.3) activity. Evidence from absorption studies with isolated membranes suggested that antigens such as the adenosine triphosphatase complex were more readily accessible to reaction with antibodies than was succinate dehydrogenase (EC 1.3.99.1), for example. Twelve antigens were located on the protoplast surface as determined by antibody absorption, and the succinylated lipomannan was identified as a major antigen. At least five other antigens possessed sugar residues that interacted with concanavalin A. With the antisera generated to isolated membranes, there was no evidence suggesting that any of these antigens was not detectable on either surface of the plasma membrane. From absorption experiments with washed, whole cells of M. lysodeikticus, it was concluded that the immunogens on the protoplast surface were also detectable on the surface of the intact cell. However, some of the components such as the succinylated lipomannan appeared to be exposed to a greater extent than others. The cytoplasmic fraction from M. lysodeikticus was used as an antigen source to generate antibodies, and 97 immunoprecipitates were resolvable by crossed immunoelectrophoresis. In the cytoplasm-anticytoplasm reference immunoelectrophoresis pattern of precipitates, three of the immunoprecipitates unique to the cytoplasmic fraction were identifiable by zymogram staining procedures as catalase (EC 1.11.1.6), isocitrate dehydrogenase (EC 1.1.1.42), and polynucleotide phosphorylase (EC 2.3.7.8). The identification of membrane and cytoplasmic antigens (including the above-mentioned enzymes) provides a sensitive analytical system for monitoring cross-contamination and antigen distribution in cellular fractions. Images PMID:144722

  11. Membrane asymmetry and expression of cell surface antigens of Micrococcus lysodeikticus established by crossed immunoelectrophoresis.

    PubMed

    Owen, P; Salton, M R

    1977-12-01

    Crossed immunoelectrophoresis of Triton X-100-solubilized plasma membranes of Micrococcus lysodeikticus established the presence of 27 discrete antigens. Individual antigens were identified as membrane components possessing enzyme activity by zymogram staining procedures and by reactivity of certain antigens with a selection of four lectins in the crossed-immunoelectrophoresis (immunoaffinoelectrophoresis) system. Absorption experiments with intact, stable protoplasts and isolated membranes established the asymmetric nature of the M. lysodeikticus plasma membranes. Of the 14 antigens with determinants accessible solely on the cytoplasmic face of the membrane, four possessed individual dehydrogenase activities, and a fifth was identifiable as a component possessing adenosine triphosphatase (EC 3.6.1.3) activity. Evidence from absorption studies with isolated membranes suggested that antigens such as the adenosine triphosphatase complex were more readily accessible to reaction with antibodies than was succinate dehydrogenase (EC 1.3.99.1), for example. Twelve antigens were located on the protoplast surface as determined by antibody absorption, and the succinylated lipomannan was identified as a major antigen. At least five other antigens possessed sugar residues that interacted with concanavalin A. With the antisera generated to isolated membranes, there was no evidence suggesting that any of these antigens was not detectable on either surface of the plasma membrane. From absorption experiments with washed, whole cells of M. lysodeikticus, it was concluded that the immunogens on the protoplast surface were also detectable on the surface of the intact cell. However, some of the components such as the succinylated lipomannan appeared to be exposed to a greater extent than others. The cytoplasmic fraction from M. lysodeikticus was used as an antigen source to generate antibodies, and 97 immunoprecipitates were resolvable by crossed immunoelectrophoresis. In the cytoplasm-anticytoplasm reference immunoelectrophoresis pattern of precipitates, three of the immunoprecipitates unique to the cytoplasmic fraction were identifiable by zymogram staining procedures as catalase (EC 1.11.1.6), isocitrate dehydrogenase (EC 1.1.1.42), and polynucleotide phosphorylase (EC 2.3.7.8). The identification of membrane and cytoplasmic antigens (including the above-mentioned enzymes) provides a sensitive analytical system for monitoring cross-contamination and antigen distribution in cellular fractions.

  12. Research and Technology Operating Plan. Summary: Fiscal year 1976 research and technology program

    NASA Technical Reports Server (NTRS)

    1976-01-01

    A compilation of the summary portions of each of the Research and Technology Operating Plans (RTOP) used for management review and control of research currently in progress throughout NASA was presented. The document is arranged in five sections. The first one contains citations and abstracts of the RTOP. This is followed by four indexes: subject, technical monitor, responsible NASA organization, and RTOP number.

  13. Adaptive harvest management for the Svalbard population of pink-footed geese: briefing summary

    USGS Publications Warehouse

    Johnson, Fred A.

    2013-01-01

    The African-Eurasian Waterbird Agreement (AEWA; http://www.unep-aewa.org/) calls for means to manage populations which cause conflicts with certain human economic activities. The Svalbard population of the pink-footed goose has been selected as the first test case for such an international species management plan to be developed. This document describes progress to date on the development of an adaptive harvest management (AHM) strategy for maintaining pink-footed goose abundance near their target level by providing for sustainable harvasts in Norway and Denmark. This briefing supplements material provided in the Progress Summary distributed to the International Working Group on February 1, 2013. We emphasize that peer review is an essential aspect of the process of developing and implementing an AHM program for pink-footed geese, and we will continue to solicit reviews by the International Working Group and their staff, as well as scientists not engaged in this effort. We wish to make the Working Group aware the the following two manuscripts have been submitted recently to refereed journals and are available upon request from the senior authors: Jensen, G.H., J. Madsen, F.A. Johnson, and M. Tamstorf. Snow conditions as an estimator of the breeding output in high-Arctic pink-footed geese Anser brachyrhynchus. Polar Biology: In review. Johnson, F.A., G.H. Jensen, J. Madsen, and B.K. Williams. Uncertainity, robustness, and the value of information in managing an expanding Arctic goose population. Ecological Modeling: In review. In addition to these manuscripts, the Progress Summary (February 1, 2013), and this Briefing Summary (April 23, 2013) an annual report will be produced in August 2013 and every summer thereafter. Additional manuscripts for journal publication are also anticipated.

  14. Cracow clean fossil fuels and energy efficiency program. Progress report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    NONE

    1998-10-01

    Since 1990 the US Department of Energy has been involved in a program aimed at reducing air pollution caused by small, coal-fired sources in Poland. The program focuses on the city of Cracow and is designed so that results will be applicable and extendable to the entire region. This report serves both as a review of the progress which has been made to date in achieving the program objectives and a summary of work still in progress.

  15. CRACOW CLEAN FOSSIL FUELS AND ENERGY EFFICIENCY PROGRAM. PROGRESS REPORT, OCTOBER 1998

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    PIERCE,B.

    1998-10-01

    Since 1990 the US Department of Energy has been involved in a program aimed at reducing air pollution caused by small, coal-fired sources in Poland. The program focuses on the city of Cracow and is designed so that results will be applicable and extendable to the entire region. This report serves both as a review of the progress which has been made to date in achieving the program objectives and a summary of work still in progress.

  16. The Amarillo National Resource Center for Plutonium. Quarterly progress detailed report, 1 November 1996--31 January 1997

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    NONE

    Progress for this quarter is given for each of the following Center programs: (1) plutonium information resource; (2) advisory function (DOE and state support); (3) environmental, public health and safety; (3) communication, education, and training; and (4) nuclear and other material studies. Both summaries of the activities and detailed reports are included.

  17. Improved radioimmunotherapy of hematologic malignancies. Progress report, November 1, 1993--October 31, 1994

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Press, O.W.

    1994-08-04

    This report summaries progress made during the time interval between November 1, 1993 and October 31, 1994 and briefly describes studies on the metabolism of antibodies targeting B cell antigens, retention of labeled antibodies by human B cell lymphocytes, and tissue distribution of Chloramine T and tyramine cellobiose labeled antibodies in mice harboring a human erythroleukemia tumor transplant.

  18. Making Schools Work for Children in Poverty. A New Framework Prepared by the Commission on Chapter 1. Summary.

    ERIC Educational Resources Information Center

    Commission on Chapter 1, Baltimore, MD.

    This document summarizes the following eight-component framework of the Commission on Chapter 1 for restructuring the Chapter 1 program: (1) have states set clear, high standards for all students; (2) devise new systems for schools to assess progress toward standards; (3) inform parents about how well their children are progressing toward…

  19. COSMIC monthly progress report

    NASA Technical Reports Server (NTRS)

    1994-01-01

    Activities of the Computer Software Management and Information Center (COSMIC) are summarized for the month of January 1994. Tables showing the current inventory of programs available from COSMIC are presented and program processing and evaluation activities are discussed. Marketing and customer service activities in this period are presented as is the progress report of NASTRAN maintenance and support. Tables of disseminations and budget summary conclude the report.

  20. Understanding Statistics - Cancer Statistics

    Cancer.gov

    Annual reports of U.S. cancer statistics including new cases, deaths, trends, survival, prevalence, lifetime risk, and progress toward Healthy People targets, plus statistical summaries for a number of common cancer types.

  1. Meeting summary: A 2017 view of Active Galactic Nuclei

    NASA Astrophysics Data System (ADS)

    Netzer, Hagai

    2018-05-01

    The topics covered in this summary review reflect the major areas discussed in the Padova meeting, in April 2017. They are divided into general categories: those areas where large progress has been made leading to a real new understanding (what we are doing "right"), and those where we are still in the dark (what we are doing "wrong"). The division reflects the status of the field as well as my subjective opinion.

  2. Therapeutic Targeting of Lipid Droplets as Disease Markers in Ovarian Cancer

    DTIC Science & Technology

    2016-03-01

    COVERED (From - To) 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 5d. PROJECT NUMBER 5e. TASK NUMBER 5f...CONTENTS Page # INTRODUCTION 2 KEYWORDS 2 PROJECT SUMMARY 2-9 KEY RESEARCH ACCOMPLISHMENTS 10 CONCLUSION AND FUTIRE PLANS 10 PUBLICATION/ABSTRACTS...Time to Recurrence, PFS- Progression Free Survival, OS-Overall Survival 3. OVERALL PROJECT SUMMARY: Milestone 1: Animal Use Approval-Prepare IACUC

  3. Democratization in the Arab World: A Summary of Lessons from Around the Globe

    DTIC Science & Technology

    2013-01-01

    key’s democratization experience together with several southern European cases . Democratization in the Arab World: A Summary of Lessons 3 termed the...examined democratization patterns in each of the following regions and focused in-depth on the cases noted in parentheses: South- ern Europe (Portugal...quickly, while in Turkey progress was more halting. In the Portuguese, Greek, and Spanish cases and, to a lesser extent, later in Turkey, the pull

  4. Comparative expression profiling reveals gene functions in female meiosis and gametophyte development in Arabidopsis.

    PubMed

    Zhao, Lihua; He, Jiangman; Cai, Hanyang; Lin, Haiyan; Li, Yanqiang; Liu, Renyi; Yang, Zhenbiao; Qin, Yuan

    2014-11-01

    Megasporogenesis is essential for female fertility, and requires the accomplishment of meiosis and the formation of functional megaspores. The inaccessibility and low abundance of female meiocytes make it particularly difficult to elucidate the molecular basis underlying megasporogenesis. We used high-throughput tag-sequencing analysis to identify genes expressed in female meiocytes (FMs) by comparing gene expression profiles from wild-type ovules undergoing megasporogenesis with those from the spl mutant ovules, which lack megasporogenesis. A total of 862 genes were identified as FMs, with levels that are consistently reduced in spl ovules in two biological replicates. Fluorescence-assisted cell sorting followed by RNA-seq analysis of DMC1:GFP-labeled female meiocytes confirmed that 90% of the FMs are indeed detected in the female meiocyte protoplast profiling. We performed reverse genetic analysis of 120 candidate genes and identified four FM genes with a function in female meiosis progression in Arabidopsis. We further revealed that KLU, a putative cytochrome P450 monooxygenase, is involved in chromosome pairing during female meiosis, most likely by affecting the normal expression pattern of DMC1 in ovules during female meiosis. Our studies provide valuable information for functional genomic analyses of plant germline development as well as insights into meiosis. © 2014 The Authors The Plant Journal © 2014 John Wiley & Sons Ltd.

  5. Progressive multiple sclerosis, cognitive function, and quality of life.

    PubMed

    Højsgaard Chow, Helene; Schreiber, Karen; Magyari, Melinda; Ammitzbøll, Cecilie; Börnsen, Lars; Romme Christensen, Jeppe; Ratzer, Rikke; Soelberg Sørensen, Per; Sellebjerg, Finn

    2018-02-01

    Patients with progressive multiple sclerosis (MS) often have cognitive impairment in addition to physical impairment. The burden of cognitive and physical impairment progresses over time, and may be major determinants of quality of life. The aim of this study was to assess to which degree quality of life correlates with physical and cognitive function in progressive MS. This is a retrospective study of 52 patients with primary progressive ( N  = 18) and secondary progressive MS ( N  = 34). Physical disability was assessed using the Expanded Disability Status Scale, Timed 25 Foot Walk (T25FW) test and 9-Hole Peg Test (9HPT). Cognitive function was assessed using Symbol Digit Modalities Test (SDMT), Paced Auditory Serial Addition Test, and Trail Making Test B (TRAIL-B). In addition, quality of life was assessed by the Short Form 36 (SF-36) questionnaire. Only measures of cognitive function correlated with the overall SF-36 quality of life score and the Mental Component Summary score from the SF-36. The only physical measure that correlated with a measure of quality of life was T25FW test, which correlated with the Physical Component Summary from the SF-36. We found no other significant correlations between the measures of cognitive function and the overall physical measures but interestingly, we found a possible relationship between the 9HPT score for the nondominant hand and the SDMT and TRAIL-B. Our findings support inclusion of measures of cognitive function in the assessment of patients with progressive MS as these correlated closer with quality of life than measures of physical impairment.

  6. Bibliography of Technical Publications and Papers, October 1979 - September 1980

    DTIC Science & Technology

    1980-11-01

    technological procedures affecting quality of radappertized chicken rolls. Institute of Food Technolo- gists, New Orleans, LA, 9-11 June 1980. 93...temperature survey of ginger beef pot roast production at a Central Food Preparation Facility. J. Food Prot., 43(4): 292-294 (1980). 180. REESE, E. T...low-dose irradiated chicken skins. Interagency Botulism Research Coordinating Coummittee, Milford, CT, 8-9 October 1980. 207. CALLO, B. Protoplast

  7. The thiol compounds glutathione and homoglutathione differentially affect cell development in alfalfa (Medicago sativa L.).

    PubMed

    Pasternak, Taras; Asard, Han; Potters, Geert; Jansen, Marcel A K

    2014-01-01

    Glutathione (GSH) is an important scavenger of Reactive Oxygen Species (ROS), precursor of metal chelating phytochelatins, xenobiotic defence compound and regulator of cell proliferation. Homoglutathione (hGSH) is a GSH homologue that is present in several taxa in the family of Fabaceae. It is thought that hGSH performs many of the stress-defence roles typically ascribed to GSH, yet little is known about the potential involvement of hGSH in controlling cell proliferation. Here we show that hGSH/GSH ratios vary across organs and cells and that these changes in hGSH/GSH ratio occur during dedifferentiation and/or cell cycle activation events. The use of a GSH/hGSH biosynthesis inhibitor resulted in impaired cytokinesis in isolated protoplasts, showing the critical importance of these thiol-compounds for cell division. However, exposure of isolated protoplasts to exogenous GSH accelerated cytokinesis, while exogenous hGSH was found to inhibit the same process. We conclude that GSH and hGSH have distinct functional roles in cell cycle regulation in Medicago sativa L. GSH is associated with meristemic cells, and promotes cell cycle activation and induction of somatic embryogenesis, while hGSH is associated with differentiated cells and embryo proliferation. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  8. Mechanical forces in plant growth and development

    NASA Technical Reports Server (NTRS)

    Fisher, D. D.; Cyr, R. J.

    2000-01-01

    Plant cells perceive forces that arise from the environment and from the biophysics of plant growth. These forces provide meaningful cues that can affect the development of the plant. Seedlings of Arabidopsis thaliana were used to examine the cytoplasmic tensile character of cells that have been implicated in the gravitropic response. Laser-trapping technology revealed that the starch-containing statoliths of the central columella cells in root caps are held loosely within the cytoplasm. In contrast, the peripheral cells have starch granules that are relatively resistant to movement. The role of the actin cytoskeleton in affecting the tensile character of these cells is discussed. To explore the role that biophysical forces might play in generating developmental cues, we have developed an experimental model system in which protoplasts, embedded in a synthetic agarose matrix, are subjected to stretching or compression. We have found that protoplasts subjected to these forces from five minutes to two hours will subsequently elongate either at right angles or parallel to the tensive or compressive force vector. Moreover, the cortical microtubules are found to be organized either at right angles or parallel to the tensive or compressive force vector. We discuss these results in terms of an interplay of information between the extracellular matrix and the underlying cytoskeleton.

  9. Rice yellow stunt rhabdovirus protein 6 suppresses systemic RNA silencing by blocking RDR6-mediated secondary siRNA synthesis.

    PubMed

    Guo, Hongyan; Song, Xiaoguang; Xie, Chuanmiao; Huo, Yan; Zhang, Fujie; Chen, Xiaoying; Geng, Yunfeng; Fang, Rongxiang

    2013-08-01

    The P6 protein of Rice yellow stunt rhabdovirus (RYSV) is a virion structural protein that can be phosphorylated in vitro. However its exact function remains elusive. We found that P6 enhanced the virulence of Potato virus X (PVX) in Nicotiana benthamiana and N. tabacum plants, suggesting that it might function as a suppressor of RNA silencing. We examined the mechanism of P6-mediated silencing suppression by transiently expressing P6 in both N. benthamiana leaves and rice protoplasts. Our results showed that P6 could repress the production of secondary siRNAs and inhibit systemic green fluorescent protein RNA silencing but did not interfere with local RNA silencing in N. benthamiana plants or in rice protoplasts. Intriguingly, P6 and RDR6 had overlapping subcellular localization and P6 bound both rice and Arabidopsis RDR6 in vivo. Furthermore, transgenic rice plants expressing P6 showed enhanced susceptibility to infection by Rice stripe virus. Hence, we propose that P6 is part of the RYSV's counter-defense machinery against the plant RNA silencing system and plays a role mainly in affecting RDR6-mediated secondary siRNA synthesis. Our work provides a new perspective on how a plant-infecting nucleorhabdovirus may counteract host RNA silencing-mediated antiviral defense.

  10. The plant cytoskeleton controls regulatory volume increase.

    PubMed

    Liu, Qiong; Qiao, Fei; Ismail, Ahmed; Chang, Xiaoli; Nick, Peter

    2013-09-01

    The ability to adjust cell volume is required for the adaptation to osmotic stress. Plant protoplasts can swell within seconds in response to hypoosmotic shock suggesting that membrane material is released from internal stores. Since the stability of plant membranes depends on submembraneous actin, we asked, whether this regulatory volume control depends on the cytoskeleton. As system we used two cell lines from grapevine which differ in their osmotic tolerance and observed that the cytoskeleton responded differently in these two cell lines. To quantify the ability for regulatory volume control, we used hydraulic conductivity (Lp) as readout and demonstrated a role of the cytoskeleton in protoplast swelling. Chelation of calcium, inhibition of calcium channels, or manipulation of membrane fluidity, did not significantly alter Lp, whereas direct manipulation of the cytoskeleton via specific chemical reagents, or indirectly, through the bacterial elicitor Harpin or activation of phospholipase D, was effective. By optochemical engineering of actin using a caged form of the phytohormone auxin we can break the symmetry of actin organisation resulting in a localised deformation of cell shape indicative of a locally increased Lp. We interpret our findings in terms of a model, where the submembraneous cytoskeleton controls the release of intracellular membrane stores during regulatory volume change. Copyright © 2013 Elsevier B.V. All rights reserved.

  11. Choline oxidation by intact spinach chloroplasts. [Spinacia oleracea L

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Weigel, P.; Lerma, C.; Hanson, A.D.

    1988-01-01

    Plants synthesize betaine by a two-step oxidation of choline (choline ..-->.. betaine aldehyde ..-->.. betaine). Protoplast-derived chloroplasts of spinach (Spinacia oleracea L.) carry out both reactions, more rapidly in light than in darkness. We investigated the light-stimulated oxidation of choline, using spinach chloroplasts isolated directly from leaves. The rates of choline oxidation obtained (dark and light rates: 10-50 and 100-300 nanomoles per hour per milligram chlorophyll, respectively) were approximately 20-fold higher than for protoplast-derived chloroplasts. Betaine aldehyde was the main product. Choline oxidation in darkness and light was suppressed by hypoxia. Neither uncouplers not the Calvin cycle inhibitor glyceraldehyde greatlymore » affected choline oxidation in the light, and maximal choline oxidation was attained far below light saturation of CO/sub 2/ fixation. The light stimulation of choline oxidation was abolished by the PSII inhibitors DCMU and dibromothymoquinone, and was partially restored by adding reduced diaminodurene, an electron donor to PSI. Both methyl viologen and phenazine methosulfate prevented choline oxidation. Adding dihydroxyacetone phosphate, which can generate NADPH in organello, doubled the dark rate of choline oxidation. These results indicate that choline oxidation in chloroplasts requires oxygen, and reducing power generated from PSI. Enzymic reactions consistent with these requirements are discussed.« less

  12. Localization of a bacterial group II intron-encoded protein in eukaryotic nuclear splicing-related cell compartments.

    PubMed

    Nisa-Martínez, Rafael; Laporte, Philippe; Jiménez-Zurdo, José Ignacio; Frugier, Florian; Crespi, Martin; Toro, Nicolás

    2013-01-01

    Some bacterial group II introns are widely used for genetic engineering in bacteria, because they can be reprogrammed to insert into the desired DNA target sites. There is considerable interest in developing this group II intron gene targeting technology for use in eukaryotes, but nuclear genomes present several obstacles to the use of this approach. The nuclear genomes of eukaryotes do not contain group II introns, but these introns are thought to have been the progenitors of nuclear spliceosomal introns. We investigated the expression and subcellular localization of the bacterial RmInt1 group II intron-encoded protein (IEP) in Arabidopsis thaliana protoplasts. Following the expression of translational fusions of the wild-type protein and several mutant variants with EGFP, the full-length IEP was found exclusively in the nucleolus, whereas the maturase domain alone targeted EGFP to nuclear speckles. The distribution of the bacterial RmInt1 IEP in plant cell protoplasts suggests that the compartmentalization of eukaryotic cells into nucleus and cytoplasm does not prevent group II introns from invading the host genome. Furthermore, the trafficking of the IEP between the nucleolus and the speckles upon maturase inactivation is consistent with the hypothesis that the spliceosomal machinery evolved from group II introns.

  13. Localization of a Bacterial Group II Intron-Encoded Protein in Eukaryotic Nuclear Splicing-Related Cell Compartments

    PubMed Central

    Nisa-Martínez, Rafael; Laporte, Philippe; Jiménez-Zurdo, José Ignacio; Frugier, Florian; Crespi, Martin; Toro, Nicolás

    2013-01-01

    Some bacterial group II introns are widely used for genetic engineering in bacteria, because they can be reprogrammed to insert into the desired DNA target sites. There is considerable interest in developing this group II intron gene targeting technology for use in eukaryotes, but nuclear genomes present several obstacles to the use of this approach. The nuclear genomes of eukaryotes do not contain group II introns, but these introns are thought to have been the progenitors of nuclear spliceosomal introns. We investigated the expression and subcellular localization of the bacterial RmInt1 group II intron-encoded protein (IEP) in Arabidopsis thaliana protoplasts. Following the expression of translational fusions of the wild-type protein and several mutant variants with EGFP, the full-length IEP was found exclusively in the nucleolus, whereas the maturase domain alone targeted EGFP to nuclear speckles. The distribution of the bacterial RmInt1 IEP in plant cell protoplasts suggests that the compartmentalization of eukaryotic cells into nucleus and cytoplasm does not prevent group II introns from invading the host genome. Furthermore, the trafficking of the IEP between the nucleolus and the speckles upon maturase inactivation is consistent with the hypothesis that the spliceosomal machinery evolved from group II introns. PMID:24391881

  14. Split luciferase complementation assay to detect regulated protein-protein interactions in rice protoplasts in a large-scale format

    PubMed Central

    2014-01-01

    Background The rice interactome, in which a network of protein-protein interactions has been elucidated in rice, is a useful resource to identify functional modules of rice signal transduction pathways. Protein-protein interactions occur in cells in two ways, constitutive and regulative. While a yeast-based high-throughput method has been widely used to identify the constitutive interactions, a method to detect the regulated interactions is rarely developed for a large-scale analysis. Results A split luciferase complementation assay was applied to detect the regulated interactions in rice. A transformation method of rice protoplasts in a 96-well plate was first established for a large-scale analysis. In addition, an antibody that specifically recognizes a carboxyl-terminal fragment of Renilla luciferase was newly developed. A pair of antibodies that recognize amino- and carboxyl- terminal fragments of Renilla luciferase, respectively, was then used to monitor quality and quantity of interacting recombinant-proteins accumulated in the cells. For a proof-of-concept, the method was applied to detect the gibberellin-dependent interaction between GIBBERELLIN INSENSITIVE DWARF1 and SLENDER RICE 1. Conclusions A method to detect regulated protein-protein interactions was developed towards establishment of the rice interactome. PMID:24987490

  15. Targeted mutagenesis in cotton (Gossypium hirsutum L.) using the CRISPR/Cas9 system

    PubMed Central

    Chen, Xiugui; Lu, Xuke; Shu, Na; Wang, Shuai; Wang, Junjuan; Wang, Delong; Guo, Lixue; Ye, Wuwei

    2017-01-01

    The CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats)/Cas9 system has been widely used for genome editing in various plants because of its simplicity, high efficiency and design flexibility. However, to our knowledge, there is no report on the application of CRISPR/Cas9-mediated targeted mutagenesis in cotton. Here, we report the genome editing and targeted mutagenesis in upland cotton (Gossypium hirsutum L., hereafter cotton) using the CRISPR/Cas9 system. We designed two guide RNAs to target distinct sites of the cotton Cloroplastos alterados 1 (GhCLA1) and vacuolar H+-pyrophosphatase (GhVP) genes. Mutations in these two genes were detected in cotton protoplasts. Most of the mutations were nucleotide substitutions, with one nucleotide insertion and one substitution found in GhCLA1 and one deletion found in GhVP in cotton protoplasts. Subsequently, the two vectors were transformed into cotton shoot apexes through Agrobacterium-mediated transformation, resulting in efficient target gene editing. Most of the mutations were nucleotide deletions, and the mutation efficiencies were 47.6–81.8% in transgenic cotton plants. Evaluation using restriction-enzyme-PCR assay and sequence analysis detected no off-target mutations. Our results indicated that the CRISPR/Cas9 system was an efficient and specific tool for targeted mutagenesis of the cotton genome. PMID:28287154

  16. Targeted mutagenesis in cotton (Gossypium hirsutum L.) using the CRISPR/Cas9 system.

    PubMed

    Chen, Xiugui; Lu, Xuke; Shu, Na; Wang, Shuai; Wang, Junjuan; Wang, Delong; Guo, Lixue; Ye, Wuwei

    2017-03-13

    The CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats)/Cas9 system has been widely used for genome editing in various plants because of its simplicity, high efficiency and design flexibility. However, to our knowledge, there is no report on the application of CRISPR/Cas9-mediated targeted mutagenesis in cotton. Here, we report the genome editing and targeted mutagenesis in upland cotton (Gossypium hirsutum L., hereafter cotton) using the CRISPR/Cas9 system. We designed two guide RNAs to target distinct sites of the cotton Cloroplastos alterados 1 (GhCLA1) and vacuolar H + -pyrophosphatase (GhVP) genes. Mutations in these two genes were detected in cotton protoplasts. Most of the mutations were nucleotide substitutions, with one nucleotide insertion and one substitution found in GhCLA1 and one deletion found in GhVP in cotton protoplasts. Subsequently, the two vectors were transformed into cotton shoot apexes through Agrobacterium-mediated transformation, resulting in efficient target gene editing. Most of the mutations were nucleotide deletions, and the mutation efficiencies were 47.6-81.8% in transgenic cotton plants. Evaluation using restriction-enzyme-PCR assay and sequence analysis detected no off-target mutations. Our results indicated that the CRISPR/Cas9 system was an efficient and specific tool for targeted mutagenesis of the cotton genome.

  17. Construction of Potent Recombinant Strain Through Intergeneric Protoplast Fusion in Endophytic Fungi for Anticancerous Enzymes Production Using Rice Straw.

    PubMed

    El-Gendy, Mervat Morsy Abbas Ahmed; Al-Zahrani, Salha Hassan Mastour; El-Bondkly, Ahmed Mohamed Ahmed

    2017-09-01

    Among all fungal endophytes isolates derived from different ethno-medical plants, the hyper-yield L-asparaginase and L-glutaminase wild strains Trichoderma sp. Gen 9 and Cladosporium sp. Gen 20 using rice straw under solid-state fermentation (SSF) were selected. The selected strains were used as parents for the intergeneric protoplast fusion program to construct recombinant strain for prompt improvement production of these enzymes in one recombinant strain. Among 21 fusants obtained, the recombinant strain AYA 20-1, with 2.11-fold and 2.58-fold increase in L-asparaginase and L-glutaminase activities more than the parental isolates Trichoderma sp. Gen 9 and Cladosporium sp. Gen 20, respectively, was achieved using rice straw under SSF. Both therapeutic enzymes L-asparaginase and L-glutaminase were purified and characterized from the culture supernatant of the recombinant AYA 20-1 strain with molecular weights of 50.6 and 83.2 kDa, respectively. Both enzymes were not metalloenzymes. Whereas thiol group blocking reagents such as p-chloromercurybenzoate and iodoacetamide totally inhibited L-asparaginase activity, which refer to sulfhydryl groups and cysteine residues involved in its catalytic activity, they have no effect toward L-glutaminase activity. Interestingly, potent anticancer, antioxidant, and antimicrobial activities were detected for both enzymes.

  18. Expression of CLAVATA3 fusions indicates rapid intracellular processing and a role of ERAD.

    PubMed

    De Marchis, Francesca; Colanero, Sara; Klein, Eva M; Mainieri, Davide; Prota, Viviana M; Bellucci, Michele; Pagliuca, Giampiero; Zironi, Elisa; Gazzotti, Teresa; Vitale, Alessandro; Pompa, Andrea

    2018-06-01

    The 12 amino acid peptide derived from the Arabidopsis soluble secretory protein CLAVATA3 (CLV3) acts at the cell surface in a signalling system that regulates the size of apical meristems. The subcellular pathway involved in releasing the peptide from its precursor is unknown. We show that a CLV3-GFP fusion expressed in transfected tobacco protoplasts or transgenic tobacco plants has very short intracellular half-life that cannot be extended by the secretory traffic inhibitors brefeldin A and wortmannin. The fusion is biologically active, since the incubation medium of protoplasts from CLV3-GFP-expressing tobacco contains the CLV3 peptide and inhibits root growth. The rapid disappearance of intact CLV3-GFP requires the signal peptide and is inhibited by the proteasome inhibitor MG132 or coexpression with a mutated CDC48 that inhibits endoplasmic reticulum-associated protein degradation (ERAD). The synthesis of CLV3-GFP is specifically supported by the endoplasmic reticulum chaperone endoplasmin in an in vivo assay. Our results indicate that processing of CLV3 starts intracellularly in an early compartment of the secretory pathway and that ERAD could play a regulatory or direct role in the active peptide synthesis. Copyright © 2018 Elsevier B.V. All rights reserved.

  19. A Rapid, Highly Efficient and Economical Method of Agrobacterium-Mediated In planta Transient Transformation in Living Onion Epidermis

    PubMed Central

    Xu, Kedong; Huang, Xiaohui; Wu, Manman; Wang, Yan; Chang, Yunxia; Liu, Kun; Zhang, Ju; Zhang, Yi; Zhang, Fuli; Yi, Liming; Li, Tingting; Wang, Ruiyue; Tan, Guangxuan; Li, Chengwei

    2014-01-01

    Transient transformation is simpler, more efficient and economical in analyzing protein subcellular localization than stable transformation. Fluorescent fusion proteins were often used in transient transformation to follow the in vivo behavior of proteins. Onion epidermis, which has large, living and transparent cells in a monolayer, is suitable to visualize fluorescent fusion proteins. The often used transient transformation methods included particle bombardment, protoplast transfection and Agrobacterium-mediated transformation. Particle bombardment in onion epidermis was successfully established, however, it was expensive, biolistic equipment dependent and with low transformation efficiency. We developed a highly efficient in planta transient transformation method in onion epidermis by using a special agroinfiltration method, which could be fulfilled within 5 days from the pretreatment of onion bulb to the best time-point for analyzing gene expression. The transformation conditions were optimized to achieve 43.87% transformation efficiency in living onion epidermis. The developed method has advantages in cost, time-consuming, equipment dependency and transformation efficiency in contrast with those methods of particle bombardment in onion epidermal cells, protoplast transfection and Agrobacterium-mediated transient transformation in leaf epidermal cells of other plants. It will facilitate the analysis of protein subcellular localization on a large scale. PMID:24416168

  20. Interaction of Bacillus subtilis spores with sodium hypochlorite, sodium dichloroisocyanurate and chloramine-T.

    PubMed

    Bloomfield, S F; Arthur, M

    1992-02-01

    Solutions of chlorine-releasing agents (CRAs) show varying activity against Bacillus subtilis spores; sodium hypochlorite (NaOCl) shows higher activity than sodium dichloroisocyanurate (NaDCC) which is more active than chloramine-T. Investigations with coat- and cortex-extracted spores indicate that resistance to CRAs depends not only on the spore coat but also the cortex. Whereas extraction of alkali-soluble coat protein increased sensitivity to NaOCl and NaDCC, degradation of coat and cortex material was required to achieve significant activity with chloramine-T. NaOCl (in the presence and absence of NaOH) and NaDCC (in the presence of NaOH only) produced degradation of spore coat and cortex material which may be related to their rapid sporicidal action at low concentrations under these conditions. By contrast, chloramine-T produced no degradation of cortex peptidoglycan and was only effective against normal and alkali-treated spores at high concentrations, requiring extraction of peptidoglycan with urea/dithiothreitol/sodium lauryl sulphate (UDS) or UDS/lysozyme to achieve significant activity at low concentrations. Results suggest that the sporicidal action of CRAs is associated with spore coat and cortex degradation causing rehydration of the protoplast allowing diffusion to the site of action on the underlying protoplast.

  1. Two different effects of calcium on aquaporins in salinity-stressed pepper plants.

    PubMed

    Martínez-Ballesta, M Carmen; Cabañero, Francisco; Olmos, Enrique; Periago, Paula María; Maurel, Christophe; Carvajal, Micaela

    2008-06-01

    Two different effects of calcium were studied, respectively, in plasma membrane vesicles and in protoplasts isolated from roots of control pepper plants (Capsicum annuum L cv. California) or of plants treated with 50 mM NaCl, 10 mM CaCl(2) or 10 mM CaCl(2) + 50 mM NaCl. Under saline conditions, osmotic water permeability (P ( f )) values decreased in protoplasts and plasma membrane vesicles, and the same reduction was observed in the PIP1 aquaporin abundance, indicating inhibitory effects of NaCl on aquaporin functionality and protein abundance. The cytosolic Ca(2+) concentration, [Ca(2+)](cyt), was reduced by salinity, as observed by confocal microscope analysis. Two different actions of Ca(2+) were observed. On the one hand, increase in free cytosolic calcium concentrations associated with stress perception may lead to aquaporin closure. On the other hand, when critical requirements of Ca(2+) were reduced (by salinity), and extra-calcium would lead to an upregulation of aquaporins, indicating that a positive role of calcium at whole plant level combined with an inhibitory mechanism at aquaporin level may work in the regulation of pepper root water transport under salt stress. However, a link between these observations and other cell signalling in relation to water channel gating remains to be established.

  2. Ten Years Old & Competent. The Fourth Stage of the Competent Children Project: A Summary of the Main Findings.

    ERIC Educational Resources Information Center

    Wylie, Cathy

    The Competent Children Project is following a group of about 500 children in the Wellington region of New Zealand from around the age of 5 until they leave school. The main aims of the project are to describe children's progress over time and to chart contributions to their progress made by family resources, early childhood education, school…

  3. Project Fire Model: Summary Progress Report, Period November 1, 1958 to April 30, 1960

    Treesearch

    W.L. Fons; H.D. Bruce; W.Y. Pong; S.S. Richards

    1960-01-01

    This report summarizes progress from November 1, 1958, to April 30, 1960, in a study conducted by the Pacific Southwest Forest and Range Experiment Station of the Forest Service in cooperation with the Office of Civil and Defense Mobilization. Called PROJECT FIRE MODEL for convenience, the project sought to develop and study a laboratory-scale fire which would...

  4. Neutron Physics Division progress report for period ending February 28, 1977

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Maienschein, F.C.

    1977-05-01

    Summaries are given of research progress in the following areas: (1) measurements of cross sections and related quantities, (2) cross section evaluations and theory, (3) cross section processing, testing, and sensitivity analysis, (4) integral experiments and their analyses, (5) development of methods for shield and reactor analyses, (6) analyses for specific systems or applications, and (7) information analysis and distribution. (SDF)

  5. Pieces of the Puzzle: Factors in the Improvement of Urban School Districts on the National Assessment of Educational Progress. Abstract

    ERIC Educational Resources Information Center

    Casserly, Michael; Price-Baugh, Ricki; Corcoran, Amanda; Lewis, Sharon; Uzzell, Renata; Simon, Candace; Heppen, Jessica; Leinwand, Steve; Salinger, Terry; de Mello, Victor Bandeira; Dogan, Enis; Novotny, Laura

    2011-01-01

    This is an abridged, summary report of selected findings from "Pieces of the Puzzle: Factors in the Improvement of Urban School Districts on the National Assessment of Educational Progress"--a comprehensive study prepared by the Council of the Great City Schools in collaboration with the American Institutes for Research (AIR) and with…

  6. Fundamental studies in geodynamics

    NASA Technical Reports Server (NTRS)

    Anderson, D. L.; Hager, B. H.; Kanamori, H.

    1981-01-01

    Research in fundamental studies in geodynamics continued in a number of fields including seismic observations and analysis, synthesis of geochemical data, theoretical investigation of geoid anomalies, extensive numerical experiments in a number of geodynamical contexts, and a new field seismic volcanology. Summaries of work in progress or completed during this report period are given. Abstracts of publications submitted from work in progress during this report period are attached as an appendix.

  7. Inflammation in Acute and Chronic Pancreatitis

    PubMed Central

    Habtezion, Aida

    2015-01-01

    Summary Immune cell contribution to the pathogenesis of acute and chronic pancreatitis is gaining more appreciation and further understanding in immune signaling presents potential therapeutic targets that can alter disease progression. PMID:26107390

  8. 77 FR 5258 - Agency Information Collection Activities: Proposed Collection; Comment Request

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-02

    ... interested stakeholders the progress and obstacles experienced by the grantees. The grantees are the... publishing the following summary of proposed collections for public comment. Interested persons are invited...

  9. Extremely Low Frequency (ELF) Communications System Ecological Monitoring Program: Plan and Summary of 1982 Progress.

    DTIC Science & Technology

    1983-08-01

    Program Acquisition Schedule A-8 LIST OF TABLES TABLE TITLE Page 1 Evolution of the ELF Communications Ecological 2 Moni tori ng Program 2 Summary of...performed on plots in maple-dominant, mixed hardwood stands in Michigan. NATIVE BEES Bees are important pollinators of flowering plants and are...SMALL MAMMALS AND NESTING BIRDS Small mammals and nesting birds represent an ecological level inter- mediate between plants and strict carnivores

  10. Cervical spondylotic myelopathy: methodological approaches to evaluate the literature and establish best evidence.

    PubMed

    Skelly, Andrea C; Hashimoto, Robin E; Norvell, Daniel C; Dettori, Joseph R; Fischer, Dena J; Wilson, Jefferson R; Tetreault, Lindsay A; Fehlings, Michael G

    2013-10-15

    Review of methods. To provide a detailed description of the methods undertaken in the articles in this focus issue pertaining to cervical spondylotic myelopathy (CSM) and ossification of the posterior longitudinal ligament (OPLL) and to describe the process used to develop summary statements and clinical recommendations regarding factors associated with the mechanisms, diagnosis, progression, and treatment of CSM and OPLL. We present methods used in conducting the systematic, evidence-based reviews and development of expert panel summary statements and clinical recommendations of the mechanisms, diagnosis, progression, and treatment of CSM and OPLL. Our intent is that clinicians will combine the information from these systematic reviews, narrative reviews, and primary research studies with an understanding of their own capacities and experience to better manage patients with CSM or OPLL and consider future research for the diagnosis and treatment of these diseases. For the systematic reviews, which make up the bulk of the studies in this focus issue, a systematic search and critical review of the English language literature was undertaken for articles published on the mechanisms, diagnosis, progression, and treatment of CSM and OPLL. Articles were screened for relevance using a priori criteria and relevant articles were critically reviewed. Whether an article was included for review depended on whether the study question was descriptive, one of therapy, or one of prognosis. The strength of evidence for the overall body of literature in each topic area was determined by 2 independent reviewers considering risk of bias, consistency, directness, and precision of results using a modification of the Grading of Recommendation Assessment, Development and Evaluation criteria. Disagreements were resolved by consensus. Findings from articles meeting inclusion criteria were summarized. From these summaries, summary statements or clinical recommendations were formulated among subject experts through a modified Delphi process using the Grading of Recommendation Assessment, Development and Evaluation approach. Methods for the 2 primary research studies and the narrative reviews are also reviewed. Because of the nature of questions that needed to be addressed, not all studies in this focus issue were amenable to systematic review. As a result, this focus issue consists of several different article types, including 1 research protocol, 2 primary research studies, 2 narrative literature reviews, 7 systematic reviews, and 3 articles that combine a systematic review component with either a narrative section (n = 2) or a provider survey (n = 1). In general, the strength of evidence ratings ranged from insufficient to moderate. Summary statements or clinical recommendations were made according to available evidence and study type: 16 summary statements were made across 8 articles, and 17 clinical recommendations were made across 9 articles. Three articles had both summary statements and clinical recommendations, 5 had summary statements only, 6 had clinical recommendations only, and 1 (the research protocol) was not amenable to either. Systematic reviews, narrative reviews, and primary research studies were undertaken to understand the mechanisms, diagnosis, progression, and treatment of CSM and OPLL and to provide summary statements and clinical recommendations. This article reports the methods used in the studies in this focus issue. SUMMARY STATEMENTS: The objectives of this focus issue were met using a variety of article and study designs, each of which has some unique methodological aspects associated with it. The reader should refer to the full article in this issue for additional details specific to that topic. The methods for systematic review follow accepted standards for rigor and, together with the application of Grading of Recommendation Assessment, Development and Evaluation, are intended to allow for transparency in the process for creating the clinical recommendation.

  11. Summary of research in progress at ICASE

    NASA Technical Reports Server (NTRS)

    1993-01-01

    This report summarizes research conducted at the Institute for Computer Applications in Science and Engineering in applied mathematics, fluid mechanics, and computer science during the period October 1, 1992 through March 31, 1993.

  12. Pomalidomide for Multiple Myeloma

    Cancer.gov

    A summary of results from a phase III trial that compared the combination of pomalidomide (Pomalyst®) and low-dose dexamethasone versus high-dose dexamethasone alone in patients with multiple myeloma that has progressed despite other treatments.

  13. For operation of the Computer Software Management and Information Center (COSMIC)

    NASA Technical Reports Server (NTRS)

    Carmon, J. L.

    1983-01-01

    Progress report on current status of computer software management and information center (COSMIC) includes the following areas: inventory, evaluation and publication, marketing, customer service, maintenance and support, and budget summary.

  14. 7 CFR 3405.19 - Monitoring progress of funded projects.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... thereafter during the life of the grant. Generally, the Annual Performance Reports should include a summary... director(s), the institution, and the food and agricultural sciences higher education system; and data on...

  15. 7 CFR 3405.19 - Monitoring progress of funded projects.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... thereafter during the life of the grant. Generally, the Annual Performance Reports should include a summary... director(s), the institution, and the food and agricultural sciences higher education system; and data on...

  16. 7 CFR 3405.19 - Monitoring progress of funded projects.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... thereafter during the life of the grant. Generally, the Annual Performance Reports should include a summary... director(s), the institution, and the food and agricultural sciences higher education system; and data on...

  17. 7 CFR 3405.19 - Monitoring progress of funded projects.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... thereafter during the life of the grant. Generally, the Annual Performance Reports should include a summary... director(s), the institution, and the food and agricultural sciences higher education system; and data on...

  18. Chemical and biological nonproliferation program. FY99 annual report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    NONE

    2000-03-01

    This document is the first of what will become an annual report documenting the progress made by the Chemical and Biological Nonproliferation Program (CBNP). It is intended to be a summary of the program's activities that will be of interest to both policy and technical audiences. This report and the annual CBNP Summer Review Meeting are important vehicles for communication with the broader chemical and biological defense and nonproliferation communities. The Chemical and Biological Nonproliferation Program Strategic Plan is also available and provides additional detail on the program's context and goals. The body of the report consists of an overviewmore » of the program's philosophy, goals and recent progress in the major program areas. In addition, an appendix is provided with more detailed project summaries that will be of interest to the technical community.« less

  19. Design and application of electromechanical actuators for deep space missions

    NASA Technical Reports Server (NTRS)

    Haskew, Tim A.; Wander, John

    1994-01-01

    This progress report documents research and development efforts performed from August 16, 1993 through August 15, 1994 on NASA Grant NAG8-240, 'Design and Application of Electromechanical Actuators for Deep Space Missions.' Since the submission of our last progress report in February 1994, our efforts have been almost entirely focused on final construction of the test stand and experiment design. Hence, this report is dedicated solely to these topics. However, updates on our research personnel and our health monitoring and fault management efforts are provided in this summary. Following this executive summary are two report sections. The first is devoted to the motor drive being constructed for the test stand. The thrust of the next section is the mechanical and hydraulic design and construction based on the planned experimental requirements. Following both major sections are three appendices.

  20. FY2016 Advanced Batteries R&D Annual Progress Report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    None, None

    The Advanced Batteries research and development (R&D) subprogram within the DOE Vehicle Technologies Office (VTO) provides support and guidance for projects focusing on batteries for plug-in electric vehicles. Program targets focus on overcoming technical barriers to enable market success including: (1) significantly reducing battery cost, (2) increasing battery performance (power, energy, durability), (3) reducing battery weight & volume, and (4) increasing battery tolerance to abusive conditions such as short circuit, overcharge, and crush. This report describes the progress made on the research and development projects funded by the Battery subprogram in 2016. This section covers the Vehicle Technologies Office overview;more » the Battery subprogram R&D overview; Advanced Battery Development project summaries; and Battery Testing, Analysis, and Design project summaries. It also includes the cover and table of contents.« less

  1. Plant cell pH-static circuit mediated by fusicoccin-binding proteins.

    PubMed

    Drabkin, A V; Trofimova, M S; Smolenskaya, I N; Klychnikov, O I; Chelysheva, V V; Babakov, A V

    1997-03-24

    On sugar beet protoplasts that carry two types of fusicoccin-binding sites, a pH downshift in a physiological range (7.0-6.6) markedly enhanced the efficiency of fusicoccin (FC) binding, mainly owing to increased avidity of low-affinity FC-binding sites. This may allow the FC-binding proteins to act as pH-sensitive modulators of cell activity, for instance, via plasma membrane H+-ATPase or potassium channels.

  2. U.C. Davis high energy particle physics research: Technical progress report -- 1990

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    NONE

    Summaries of progress made for this period is given for each of the following areas: (1) Task A--Experiment, H1 detector at DESY; (2) Task C--Experiment, AMY detector at KEK; (3) Task D--Experiment, fixed target detectors at Fermilab; (4) Task F--Experiment, PEP detector at SLAC and pixel detector; (5) Task B--Theory, particle physics; and (6) Task E--Theory, particle physics.

  3. Twenty-third Semiannual Report of the Commission to the Congress, January 1958. Progress in peaceful uses of atomic energy July - December 1957

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Strauss, Lewis L.

    1958-01-31

    The document represents the twenty-third semiannual Atomic Energy Commission (AEC) report to Congress. The report sums up the major activities and developments in the national atomic energy program covering the period July - December 1957. A special part one of this semiannual report is titled ''Progress in the Peaceful Uses of Atomic Energy - A 3-year Summary.

  4. Annual Progress Report FY-92. Volume 2

    DTIC Science & Technology

    1992-01-01

    OBJECTIVE To measure the effect of methotrexate on interleukin-l ( IL - 1 ) induced ICAN-l expression in cultured human fibroblasts and adenocarcinoma cells...SUMMARY SHEET TITLE: Effect of IL - 1 on Glucocorticoid Inhibition of Wound Healing KEYWORDS: IL - 1 , wound healing PRINCIPAL INVESTIGATOR: Schoenfeld, Phil CPT...PROGRESS Cultured cells were incubated with IL -l to stimulate ICAM-l expression. In general, the cells responded well. ICAM- 1 was readily detectable

  5. Summary of Progress on SIG Ft. Ord ESTCP DemVal

    DTIC Science & Technology

    2007-04-01

    We report on progress under an ESTCP demonstration plan dedicated to demonstrating active learning - based UXO detection on an actual former UXO site...Ft. Ord), using EMI data. In addition to describing the details of the active - learning algorithm, we discuss techniques that were required when...terms of two dipole-moment magnitudes and two resonant frequencies. Information-theoretic active learning is then conducted on all anomalies to

  6. Measuring software development characteristics in the local environment. [considering project requirements for spacecraft control

    NASA Technical Reports Server (NTRS)

    Basili, V. R.; Zelkowitz, M. V.

    1978-01-01

    In a brief evaluation of software-related considerations, it is found that suitable approaches for software development depend to a large degree on the characteristics of the particular project involved. An analysis is conducted of development problems in an environment in which ground support software is produced for spacecraft control. The amount of work involved is in the range from 6 to 10 man-years. Attention is given to a general project summary, a programmer/analyst survey, a component summary, a component status report, a resource summary, a change report, a computer program run analysis, aspects of data collection on a smaller scale, progress forecasting, problems of overhead, and error analysis.

  7. Summary of the Advanced Reactor Design Criteria (ARDC) Phase 2 Activities

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Holbrook, Mark Raymond

    This report provides an end-of-year summary reflecting the progress and status of proposed regulatory design criteria for advanced non-LWR designs in accordance with the Level 3 milestone in M3AT-15IN2001017 in work package AT-15IN200101. These criteria have been designated as ARDC, and they provide guidance to future applicants for addressing the GDC that are currently applied specifically to LWR designs. The report provides a summary of Phase 2 activities related to the various tasks associated with ARDC development and the subsequent development of example adaptations of ARDC for Sodium Fast Reactor (SFR) and modular High Temperature Gas-cooled Reactor (HTGR) designs.

  8. Research and technology operating plan summary: Fiscal year 1975 research and technology program. [space programs, energy technology, and aerospace sciences

    NASA Technical Reports Server (NTRS)

    1975-01-01

    Summaries are presented of Research and Technology Operating Plans currently in progress throughout NASA. Citations and abstracts of the operating plans are presented along with a subject index, technical monitor index, and responsible NASA organization index. Research programs presented include those carried out in the Office of Aeronautics and Space Technology, Office of Energy Programs, Office of Applications, Office of Space Sciences, Office of Tracking and Data Acquisition, and the Office of Manned Space Flight.

  9. Walter Reed Army Medical Center, Washington, DC Annual Progress Report FY-89. Volume 2. Part 1

    DTIC Science & Technology

    1990-01-02

    recurrent head and neck cancer who meet the eligibility requirements and consent to the protocol will have central venous catheter placed (if one is...DATE: 06/29/89 WORK UNIT # 6220 DETAIL SUMMARY SHEET TITLE: Epidemiology of HIV In Pediatric and Perinatal Patients - A Natural History Study...of HIV in clinical samples. 16 I I REPORT DATE: 04/04/89 WORK UNIT # 8804 DETAIL SUMMARY SHEET TITLE: The Natural History of HIV Infection and Disease

  10. Enzalutamide Improves Survival in Patients with Metastatic Prostate Cancer

    Cancer.gov

    A summary of results from an international phase III trial that compared enzalutamide (Xtandi®) and placebo for the treatment of metastatic prostate cancer that had progressed during treatment with androgen deprivation therapy.

  11. Rituximab Retreatment for Low-Tumor Burden Follicular Lymphoma

    Cancer.gov

    A summary of results from a randomized clinical trial of patients with low–tumor burden follicular lymphoma that compared maintenance therapy with rituximab versus retreatment with rituximab only when there was evidence of disease progression.

  12. IMPLEMENTATION REVIEW LETTERS, 2002

    EPA Science Inventory

    The following letters provide a summary of the Environmental Protection Agencys comments regarding 2002 Implementation Review of nineteen estuary programs in the National Estuary Program. Various strengths within the programs included use of implementation progress and tracking s...

  13. Guaranteed Time Observations Support for Goddard High Resolution Spectrograph (GHRS) on HST

    NASA Technical Reports Server (NTRS)

    Beaver, Edward

    1998-01-01

    We assemble this final grant report by combining our previously submitted progress reports with the last year's progress report. Section 2 is the progress report for the June 1, 1991 to Nov. 14, 1995 period. Section 4 is the progress report for the Nov. 14, 1996 to Dec. 31, 1996 period. Section 5 is the progress report for the Nov. 14 to Aug. 31, 1997 period. Section 6 is the new progress report for the Sept. 15, 1997 to Nov. 14, 1998 final period. Section 3 is a summary of our spare detector high voltage transient tests activity in 1992 in support of the renewed safe operation of the GHRS HST D1 detector. Note that we have left the format of each progress report the same as originally sent out. The slight differences in format presentation are thus intended.

  14. UTD at TREC 2014: Query Expansion for Clinical Decision Support

    DTIC Science & Technology

    2014-11-01

    Description: A 62-year-old man sees a neurologist for progressive memory loss and jerking movements of the lower ex- tremities. Neurologic examination confirms...infiltration. Summary: 62-year-old man with progressive memory loss and in- voluntary leg movements. Brain MRI reveals cortical atrophy, and cortical...latent topics produced by the Latent Dirichlet Allocation (LDA) on the TREC-CDS corpus of scientific articles. The position of words “ loss ” and “ memory

  15. Recent Progress in Electromagnetic Absorption and Dosimetry in Biological Systems.

    DTIC Science & Technology

    1978-12-21

    AEROSPACE M!DICAL RESEARCH LABORATORY NAVAL AIR STATION PENSACOLA, FLORIDA 32508 L4 oj6L I SUMMARY PAGE Ti9(PROSLEM Dosimetry , as a subset of research In...absonce of sound dosimetry design, lacks credibility. This study provides a usable orientation in present and future dosimetric technology through a...leading experiment; while at other times experimental results lead the way. Progress In absorption and dosimetry Is still urderway, and higher degrees

  16. Highlights of 1980 activities

    NASA Technical Reports Server (NTRS)

    1980-01-01

    Progress in the Space Transportation System is reported. A review of the Voyager 1 mission is presented along with a summary of facts gathered on its Saturn encounter. Research and development in energy technology, space tracking, and data systems is described.

  17. Publisher Correction: Measuring progress from nationally determined contributions to mid-century strategies

    NASA Astrophysics Data System (ADS)

    Iyer, Gokul; Ledna, Catherine; Clarke, Leon; Edmonds, James; McJeon, Haewon; Kyle, Page; Williams, James H.

    2018-03-01

    In the version of this Article previously published, technical problems led to the wrong summary appearing on the homepage, and an incorrect Supplementary Information file being uploaded. Both errors have now been corrected.

  18. Atmospheric planetary-wave response to external forcing

    NASA Technical Reports Server (NTRS)

    Stevens, D. E.; Reiter, E. R.

    1983-01-01

    A summary of the progress report is given, covering the following areas: atmospheric circulation, planetary waves, adaption of the model to the Cyber 205, continental heat flux anomalies, and nonlinear evolution of inertial instabilities in the tropics.

  19. Near-Term Electric Vehicle Program. Phase II: Mid-Term Summary Report.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    None

    1978-08-01

    The Near Term Electric Vehicle (NTEV) Program is a constituent elements of the overall national Electric and Hybrid Vehicle Program that is being implemented by the Department of Energy in accordance with the requirements of the Electric and Hybrid Vehicle Research, Development, and Demonstration Act of 1976. Phase II of the NTEV Program is focused on the detailed design and development, of complete electric integrated test vehicles that incorporate current and near-term technology, and meet specified DOE objectives. The activities described in this Mid-Term Summary Report are being carried out by two contractor teams. The prime contractors for these contractormore » teams are the General Electric Company and the Garrett Corporation. This report is divided into two discrete parts. Part 1 describes the progress of the General Electric team and Part 2 describes the progress of the Garrett team.« less

  20. Quadruple Burden of HIV/AIDS, Tuberculosis, Chronic Intestinal Parasitoses, and Multiple Micronutrient Deficiency in Ethiopia: A Summary of Available Findings

    PubMed Central

    Amare, Bemnet; Moges, Beyene; Mulu, Andargachew; Yifru, Sisay; Kassu, Afework

    2015-01-01

    Human immunodeficiency virus (HIV), tuberculosis (TB), and helminthic infections are among the commonest public health problems in the sub-Saharan African countries like Ethiopia. Multiple micronutrient deficiencies also known as the “hidden hunger” are common in people living in these countries either playing a role in their pathogenesis or as consequences. This results in a vicious cycle of multiple micronutrient deficiencies and infection/disease progression. As infection is profoundly associated with nutritional status resulting from decreased nutrient intake, decreased nutrient absorption, and nutrient losses, micronutrient deficiencies affect immune system and impact infection and diseases progression. As a result, micronutrients, immunity, and infection are interrelated. The goal of this review is therefore to provide a summary of available findings regarding the “quadruple burden trouble” of HIV, TB, intestinal parasitic infections, and multiple micronutrient deficiencies to describe immune-modulating effects related to disorders. PMID:25767808

  1. Quadruple burden of HIV/AIDS, tuberculosis, chronic intestinal parasitoses, and multiple micronutrient deficiency in ethiopia: a summary of available findings.

    PubMed

    Amare, Bemnet; Moges, Beyene; Mulu, Andargachew; Yifru, Sisay; Kassu, Afework

    2015-01-01

    Human immunodeficiency virus (HIV), tuberculosis (TB), and helminthic infections are among the commonest public health problems in the sub-Saharan African countries like Ethiopia. Multiple micronutrient deficiencies also known as the "hidden hunger" are common in people living in these countries either playing a role in their pathogenesis or as consequences. This results in a vicious cycle of multiple micronutrient deficiencies and infection/disease progression. As infection is profoundly associated with nutritional status resulting from decreased nutrient intake, decreased nutrient absorption, and nutrient losses, micronutrient deficiencies affect immune system and impact infection and diseases progression. As a result, micronutrients, immunity, and infection are interrelated. The goal of this review is therefore to provide a summary of available findings regarding the "quadruple burden trouble" of HIV, TB, intestinal parasitic infections, and multiple micronutrient deficiencies to describe immune-modulating effects related to disorders.

  2. Effects of Mn2+ Levels on the Resistance Properties of Bacillus cereus Spores

    DTIC Science & Technology

    2013-01-01

    In contrast, Bacillus subtilis spores with over a 200-fold range of protoplast Mn levels exhibited no significant differences in resistance to... Bacillus subtilis . J. Bacteriol. 189:8458-8466. Coleman WH, Zhang P, Li YQ, Setlow P (2010). Mechanism of killing of spores of Bacillus cereus and...Gaidamakova EK, Matrosova VY, Daly MJ, Setlow P (2011). Effects of levels of Mn and Fe on Bacillus subtilis spore resistance, and effects of Mn 2

  3. Inactivation of the indole-diterpene biosynthetic gene cluster of Claviceps paspali by Agrobacterium-mediated gene replacement.

    PubMed

    Kozák, László; Szilágyi, Zoltán; Vágó, Barbara; Kakuk, Annamária; Tóth, László; Molnár, István; Pócsi, István

    2018-04-01

    The hypocrealean fungus Claviceps paspali is a parasite of wild grasses. This fungus is widely utilized in the pharmaceutical industry for the manufacture of ergot alkaloids, but also produces tremorgenic and neurotoxic indole-diterpene (IDT) secondary metabolites such as paspalitrems A and B. IDTs cause significant losses in agriculture and represent health hazards that threaten food security. Conversely, IDTs may also be utilized as lead compounds for pharmaceutical drug discovery. Current protoplast-mediated transformation protocols of C. paspali are inadequate as they suffer from inefficiencies in protoplast regeneration, a low frequency of DNA integration, and a low mitotic stability of the nascent transformants. We adapted and optimized Agrobacterium tumefaciens-mediated transformation (ATMT) for C. paspali and validated this method with the straightforward creation of a mutant strain of this fungus featuring a targeted replacement of key genes in the putative IDT biosynthetic gene cluster. Complete abrogation of IDT production in isolates of the mutant strain proved the predicted involvement of the target genes in the biosynthesis of IDTs. The mutant isolates continued to produce ergot alkaloids undisturbed, indicating that equivalent mutants generated in industrial ergot producers may have a better safety profile as they are devoid of IDT-type mycotoxins. Meanwhile, ATMT optimized for Claviceps spp. may open the door for the facile genetic engineering of these industrially and ecologically important organisms.

  4. Maize Elongin C interacts with the viral genome-linked protein, VPg, of Sugarcane mosaic virus and facilitates virus infection

    PubMed Central

    Zhu, Min; Chen, Yuting; Ding, Xin Shun; Webb, Stephen L; Zhou, Tao; Nelson, Richard S; Fan, Zaifeng

    2014-01-01

    The viral genome-linked protein, VPg, of potyviruses is involved in viral genome replication and translation. To determine host proteins that interact with Sugarcane mosaic virus (SCMV) VPg, a yeast two-hybrid screen was used and a maize (Zea mays) Elongin C (ZmElc) protein was identified. ZmELC transcript was observed in all maize organs, but most highly in leaves and pistil extracts, and ZmElc was present in the cytoplasm and nucleus of maize cells in the presence or absence of SCMV. ZmELC expression was increased in maize tissue at 4 and 6 d post SCMV inoculation. When ZmELC was transiently overexpressed in maize protoplasts the accumulation of SCMV RNA was approximately doubled compared with the amount of virus in control protoplasts. Silencing ZmELC expression using a Brome mosaic virus-based gene silencing vector (virus-induced gene silencing) did not influence maize plant growth and development, but did decrease RNA accumulation of two isolates of SCMV and host transcript encoding ZmeIF4E during SCMV infection. Interestingly, Maize chlorotic mottle virus, from outside the Potyviridae, was increased in accumulation after silencing ZmELC expression. Our results describe both the location of ZmElc expression in maize and a new activity associated with an Elc: support of potyvirus accumulation. PMID:24954157

  5. Maize Elongin C interacts with the viral genome-linked protein, VPg, of Sugarcane mosaic virus and facilitates virus infection.

    PubMed

    Zhu, Min; Chen, Yuting; Ding, Xin Shun; Webb, Stephen L; Zhou, Tao; Nelson, Richard S; Fan, Zaifeng

    2014-09-01

    The viral genome-linked protein, VPg, of potyviruses is involved in viral genome replication and translation. To determine host proteins that interact with Sugarcane mosaic virus (SCMV) VPg, a yeast two-hybrid screen was used and a maize (Zea mays) Elongin C (ZmElc) protein was identified. ZmELC transcript was observed in all maize organs, but most highly in leaves and pistil extracts, and ZmElc was present in the cytoplasm and nucleus of maize cells in the presence or absence of SCMV. ZmELC expression was increased in maize tissue at 4 and 6 d post SCMV inoculation. When ZmELC was transiently overexpressed in maize protoplasts the accumulation of SCMV RNA was approximately doubled compared with the amount of virus in control protoplasts. Silencing ZmELC expression using a Brome mosaic virus-based gene silencing vector (virus-induced gene silencing) did not influence maize plant growth and development, but did decrease RNA accumulation of two isolates of SCMV and host transcript encoding ZmeIF4E during SCMV infection. Interestingly, Maize chlorotic mottle virus, from outside the Potyviridae, was increased in accumulation after silencing ZmELC expression. Our results describe both the location of ZmElc expression in maize and a new activity associated with an Elc: support of potyvirus accumulation. © 2014 The Authors. New Phytologist © 2014 New Phytologist Trust.

  6. A Method for Characterizing Phenotypic Changes in Highly Variable Cell Populations and its Application to High Content Screening of Arabidopsis thaliana Protoplastsa

    PubMed Central

    Johnson, Gregory R.; Kangas, Joshua D.; Dovzhenko, Alexander; Trojok, Rüdiger; Voigt, Karsten; Majarian, Timothy D.; Palme, Klaus; Murphy, Robert F.

    2017-01-01

    Quantitative image analysis procedures are necessary for the automated discovery of effects of drug treatment in large collections of fluorescent micrographs. When compared to their mammalian counterparts, the effects of drug conditions on protein localization in plant species are poorly understood and underexplored. To investigate this relationship, we generated a large collection of images of single plant cells after various drug treatments. For this, protoplasts were isolated from six transgenic lines of A. thaliana expressing fluorescently tagged proteins. Nine drugs at three concentrations were applied to protoplast cultures followed by automated image acquisition. For image analysis, we developed a cell segmentation protocol for detecting drug effects using a Hough-transform based region of interest detector and a novel cross-channel texture feature descriptor. In order to determine treatment effects, we summarized differences between treated and untreated experiments with an L1 Cramér-von Mises statistic. The distribution of these statistics across all pairs of treated and untreated replicates was compared to the variation within control replicates to determine the statistical significance of observed effects. Using this pipeline, we report the dose dependent drug effects in the first high-content Arabidopsis thaliana drug screen of its kind. These results can function as a baseline for comparison to other protein organization modeling approaches in plant cells. PMID:28245335

  7. A laser microsurgical method of cell wall removal allows detection of large-conductance ion channels in the guard cell plasma membrane

    NASA Technical Reports Server (NTRS)

    Miedema, H.; Henriksen, G. H.; Assmann, S. M.; Evans, M. L. (Principal Investigator)

    1999-01-01

    Application of patch clamp techniques to higher-plant cells has been subject to the limitation that the requisite contact of the patch electrode with the cell membrane necessitates prior enzymatic removal of the plant cell wall. Because the wall is an integral component of plant cells, and because cell-wall-degrading enzymes can disrupt membrane properties, such enzymatic treatments may alter ion channel behavior. We compared ion channel activity in enzymatically isolated protoplasts of Vicia faba guard cells with that found in membranes exposed by a laser microsurgical technique in which only a tiny portion of the cell wall is removed while the rest of the cell remains intact within its tissue environment. "Laser-assisted" patch clamping reveals a new category of high-conductance (130 to 361 pS) ion channels not previously reported in patch clamp studies on plant plasma membranes. These data indicate that ion channels are present in plant membranes that are not detected by conventional patch clamp techniques involving the production of individual plant protoplasts isolated from their tissue environment by enzymatic digestion of the cell wall. Given the large conductances of the channels revealed by laser-assisted patch clamping, we hypothesize that these channels play a significant role in the regulation of ion content and electrical signalling in guard cells.

  8. Suppression of xylan endotransglycosylase PtxtXyn10A affects cellulose microfibril angle in secondary wall in aspen wood.

    PubMed

    Derba-Maceluch, Marta; Awano, Tatsuya; Takahashi, Junko; Lucenius, Jessica; Ratke, Christine; Kontro, Inkeri; Busse-Wicher, Marta; Kosik, Ondrej; Tanaka, Ryo; Winzéll, Anders; Kallas, Åsa; Leśniewska, Joanna; Berthold, Fredrik; Immerzeel, Peter; Teeri, Tuula T; Ezcurra, Ines; Dupree, Paul; Serimaa, Ritva; Mellerowicz, Ewa J

    2015-01-01

    Certain xylanases from family GH10 are highly expressed during secondary wall deposition, but their function is unknown. We carried out functional analyses of the secondary-wall specific PtxtXyn10A in hybrid aspen (Populus tremula × tremuloides). PtxtXyn10A function was analysed by expression studies, overexpression in Arabidopsis protoplasts and by downregulation in aspen. PtxtXyn10A overexpression in Arabidopsis protoplasts resulted in increased xylan endotransglycosylation rather than hydrolysis. In aspen, the enzyme was found to be proteolytically processed to a 68 kDa peptide and residing in cell walls. Its downregulation resulted in a corresponding decrease in xylan endotransglycosylase activity and no change in xylanase activity. This did not alter xylan molecular weight or its branching pattern but affected the cellulose-microfibril angle in wood fibres, increased primary growth (stem elongation, leaf formation and enlargement) and reduced the tendency to form tension wood. Transcriptomes of transgenic plants showed downregulation of tension wood related genes and changes in stress-responsive genes. The data indicate that PtxtXyn10A acts as a xylan endotransglycosylase and its main function is to release tensional stresses arising during secondary wall deposition. Furthermore, they suggest that regulation of stresses in secondary walls plays a vital role in plant development. © 2014 The Authors. New Phytologist © 2014 New Phytologist Trust.

  9. Identification and Characterization of Cell Wall Proteins of a Toxic Dinoflagellate Alexandrium catenella Using 2-D DIGE and MALDI TOF-TOF Mass Spectrometry

    PubMed Central

    Wang, Da-Zhi; Dong, Hong-Po; Li, Cheng; Xie, Zhang-Xian; Lin, Lin; Hong, Hua-Sheng

    2011-01-01

    The cell wall is an important subcellular component of dinoflagellate cells with regard to various aspects of cell surface-associated ecophysiology, but the full range of cell wall proteins (CWPs) and their functions remain to be elucidated. This study identified and characterized CWPs of a toxic dinoflagellate, Alexandrium catenella, using a combination of 2D fluorescence difference gel electrophoresis (DIGE) and MALDI TOF-TOF mass spectrometry approaches. Using sequential extraction and temperature shock methods, sequentially extracted CWPs and protoplast proteins, respectively, were separated from A. catenella. From the comparison between sequentially extracted CWPs labeled with Cy3 and protoplast proteins labeled with Cy5, 120 CWPs were confidently identified in the 2D DIGE gel. These proteins gave positive identification of protein orthologues in the protein database using de novo sequence analysis and homology-based search. The majority of the prominent CWPs identified were hypothetical or putative proteins with unknown function or no annotation, while cell wall modification enzymes, cell wall structural proteins, transporter/binding proteins, and signaling and defense proteins were tentatively identified in agreement with the expected role of the extracellular matrix in cell physiology. This work represents the first attempt to investigate dinoflagellate CWPs and provides a potential tool for future comprehensive characterization of dinoflagellate CWPs and elucidation of their physiological functions. PMID:21904561

  10. Mechanism of Aluminum Inhibition of Net 45Ca2+ Uptake by Amaranthus Protoplasts 1

    PubMed Central

    Rengel, Zdenko; Elliott, Daphne C.

    1992-01-01

    Calcium ions serve as a second messenger in signal transduction and metabolic regulation. Effects of Al on calcium homeostasis remain to be elucidated. Short-term net 45Ca2+ uptake by Amaranthus tricolor protoplasts was monitored from uptake media prepared to test the influence of pH, Al, and various inhibitors. Accumulation of 45Ca2+ increased during the first 3 to 6 minutes and then leveled off or declined. Al and Ca2+ channel blockers (verapamil and bepridil) decreased net 45Ca2+ uptake. This decrease was more pronounced when Al and bepridil were both present in uptake media, but Al did not aggravate verapamil-induced reduction of net 45Ca2+ uptake. Erythrosin B and calmidazolium each increased net 45Ca2+ uptake, probably by interfering with Ca2+ efflux. This effect was undetectable in the presence of Al. Mycophenolic acid decreased net 45Ca2+ uptake; guanosine alleviated this effect. Al-induced reduction of net 45Ca2+ uptake was not aggravated by mycophenolic acid. Net 45Ca2+ uptake was generally less at pH 4.5 than at 5.5 for all treatments. It is concluded that Al ions affect net 45Ca2+ uptake by binding to the verapamil-specific channel site that is different from the bepridil-specific one, as well as by interfering with the action of guanosine 5′-triphosphate-binding proteins. PMID:16668688

  11. Selective Regulation of Maize Plasma Membrane Aquaporin Trafficking and Activity by the SNARE SYP121[W

    PubMed Central

    Besserer, Arnaud; Burnotte, Emeline; Bienert, Gerd Patrick; Chevalier, Adrien S.; Errachid, Abdelmounaim; Grefen, Christopher; Blatt, Michael R.; Chaumont, François

    2012-01-01

    Plasma membrane intrinsic proteins (PIPs) are aquaporins facilitating the diffusion of water through the cell membrane. We previously showed that the traffic of the maize (Zea mays) PIP2;5 to the plasma membrane is dependent on the endoplasmic reticulum diacidic export motif. Here, we report that the post-Golgi traffic and water channel activity of PIP2;5 are regulated by the SNARE (for soluble N-ethylmaleimide-sensitive factor protein attachment protein receptor) SYP121, a plasma membrane resident syntaxin involved in vesicle traffic, signaling, and regulation of K+ channels. We demonstrate that the expression of the dominant-negative SYP121-Sp2 fragment in maize mesophyll protoplasts or epidermal cells leads to a decrease in the delivery of PIP2;5 to the plasma membrane. Protoplast and oocyte swelling assays showed that PIP2;5 water channel activity is negatively affected by SYP121-Sp2. A combination of in vitro (copurification assays) and in vivo (bimolecular fluorescence complementation, Förster resonance energy transfer, and yeast split-ubiquitin) approaches allowed us to demonstrate that SYP121 and PIP2;5 physically interact. Together with previous data demonstrating the role of SYP121 in regulating K+ channel trafficking and activity, these results suggest that SYP121 SNARE contributes to the regulation of the cell osmotic homeostasis. PMID:22942383

  12. Selective regulation of maize plasma membrane aquaporin trafficking and activity by the SNARE SYP121.

    PubMed

    Besserer, Arnaud; Burnotte, Emeline; Bienert, Gerd Patrick; Chevalier, Adrien S; Errachid, Abdelmounaim; Grefen, Christopher; Blatt, Michael R; Chaumont, François

    2012-08-01

    Plasma membrane intrinsic proteins (PIPs) are aquaporins facilitating the diffusion of water through the cell membrane. We previously showed that the traffic of the maize (Zea mays) PIP2;5 to the plasma membrane is dependent on the endoplasmic reticulum diacidic export motif. Here, we report that the post-Golgi traffic and water channel activity of PIP2;5 are regulated by the SNARE (for soluble N-ethylmaleimide-sensitive factor protein attachment protein receptor) SYP121, a plasma membrane resident syntaxin involved in vesicle traffic, signaling, and regulation of K(+) channels. We demonstrate that the expression of the dominant-negative SYP121-Sp2 fragment in maize mesophyll protoplasts or epidermal cells leads to a decrease in the delivery of PIP2;5 to the plasma membrane. Protoplast and oocyte swelling assays showed that PIP2;5 water channel activity is negatively affected by SYP121-Sp2. A combination of in vitro (copurification assays) and in vivo (bimolecular fluorescence complementation, Förster resonance energy transfer, and yeast split-ubiquitin) approaches allowed us to demonstrate that SYP121 and PIP2;5 physically interact. Together with previous data demonstrating the role of SYP121 in regulating K(+) channel trafficking and activity, these results suggest that SYP121 SNARE contributes to the regulation of the cell osmotic homeostasis.

  13. A comparison of Agrobacterium-mediated transformation and protoplast-mediated transformation with CRISPR-Cas9 and bipartite gene targeting substrates, as effective gene targeting tools for Aspergillus carbonarius.

    PubMed

    Weyda, István; Yang, Lei; Vang, Jesper; Ahring, Birgitte K; Lübeck, Mette; Lübeck, Peter S

    2017-04-01

    In recent years, versatile genetic tools have been developed and applied to a number of filamentous fungi of industrial importance. However, the existing techniques have limitations when it comes to achieve the desired genetic modifications, especially for efficient gene targeting. In this study, we used Aspergillus carbonarius as a host strain due to its potential as a cell factory, and compared three gene targeting techniques by disrupting the ayg1 gene involved in the biosynthesis of conidial pigment in A. carbonarius. The absence of the ayg1 gene leads to phenotypic change in conidia color, which facilitated the analysis on the gene targeting frequency. The examined transformation techniques included Agrobacterium-mediated transformation (AMT) and protoplast-mediated transformation (PMT). Furthermore, the PMT for the disruption of the ayg1 gene was carried out with bipartite gene targeting fragments and the recently adapted CRISPR-Cas9 system. All three techniques were successful in generating Δayg1 mutants, but showed different efficiencies. The most efficient method for gene targeting was AMT, but further it was shown to be dependent on the choice of Agrobacterium strain. However, there are different advantages and disadvantages of all three gene targeting methods which are discussed, in order to facilitate future approaches for fungal strain improvements. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Surveying Florida MPO readiness to incorporate innovative technologies into long range transportation plans [summary].

    DOT National Transportation Integrated Search

    2016-08-01

    In this project, researchers from the University of Florida : Transportation Institute (UFTI) surveyed MPOs throughout Florida to gain an understanding of : their progress and their needs in incorporating AV into their LRTPs.

  15. Statistical and operational summaries

    NASA Technical Reports Server (NTRS)

    Disalvo, J.

    1972-01-01

    Statistical progress indicator forms are presented on the financial management of the research allocations. Promotional activities, conference participants, and services are tabulated. The staffing and activity levels are also discussed, as well as the fee schedule revision and the standard interest profile offerings.

  16. DOE Office of Scientific and Technical Information (OSTI.GOV)

    None

    Brief summaries are presented of research in progress in the fields of radiobiology, genetics, hematology, immunology physiology. biochemistry, bacteriology, enzymology, microbiology, photosynthesis, biophysics, radiation protection, and related fields. A list is included of 240 publications in the world literature that report results of completed studies. (CH)

  17. Control of embankment settlement field verification on PCPT prediction methods : tech summary.

    DOT National Transportation Integrated Search

    2011-07-01

    Depending on loading and embankment height, the magnitude and progression of settlement can signifi cantly impact the safety and : serviceability of the infrastructures that are constructed on saturated fi ne-grained soils. Therefore, the constructio...

  18. Intelligent Transportation Systems : a summary of progress and results, November 2008.

    DOT National Transportation Integrated Search

    2008-11-01

    The Federal Intelligent Transportation Systems (ITS) Program began in response to a directive from Congress to employ advanced technologies in transportation in order to keep the transportation industry in lockstep with the nations move toward use...

  19. ECOLOGICAL INDICATORS IN RISK ASSESSMENT WORKSHOP SUMMARY

    EPA Science Inventory

    Ecological indicators can be defined as relatively simple measurements that relay scientific information about complex ecosystems. Such indicators are used to characterize risk in ecological risk assessment (ERA) and to mark progress toward resource management goals. In late 1997...

  20. ECOLOGICAL INDICATORS IN RISK ASSESSMENT: WORKSHOP SUMMARY

    EPA Science Inventory

    Ecological indicators can be defined as relatively simple measurements that relay scientific information about complex ecosystems. Such indicators are used to characterize risk in ecological risk assessment and to mark progress toward resource management goals. In late 1997 scien...

  1. 2013 Reading Assessment Report Card: Summary Data Tables for National and State Sample Sizes, Participation Rates, and Proportions of SD and ELL Students Identified. [Technical Appendix. NCES 2014-451

    ERIC Educational Resources Information Center

    National Center for Education Statistics, 2013

    2013-01-01

    This document represents one of three appendices associated with "The Nation's Report Card: A First Look--2013 Mathematics and Reading. National Assessment of Educational Progress at Grade 4 and 8. NCES 2014-451." It includes tabular data relating to the reading portion of the National Assessment of Education Progress at Grade 4 and 8.…

  2. Olympic Fisher Reintroduction Project- 2009 Progress Report

    USGS Publications Warehouse

    Lewis, Jeffrey C.; Happe, Patti J.; Jenkins, Kurt J.; Manson, David J.

    2009-01-01

    The 2009 progress report is a summary of the reintroduction, monitoring, and research efforts undertaken during the first two years of the Olympic fisher reintroduction project. Jeffrey C. Lewis of Washington Department of Fish and Wildlife, Patti J. Happe of Olympic National Park, and Kurt J. Jenkins of U. S. Geological Survey are the principal investigators of the monitoring and research program associated with the reintroduction. David J. Manson of Olympic National Park is the lead biological

  3. Olympic Fisher Reintroduction Project: 2010 Progress Report

    USGS Publications Warehouse

    Lewis, Jeffrey C.; Happe, Patti J.; Jenkins, Kurt J.; Manson, David J.

    2010-01-01

    The 2010 progress report is a summary of the reintroduction, monitoring, and research efforts undertaken during the third year of the Olympic fisher reintroduction project. Jeffrey C. Lewis of Washington Department of Fish and Wildlife, Patti J. Happe of Olympic National Park, and Kurt J. Jenkins of U. S. Geological Survey are the principal investigators of the monitoring and research program associated with the reintroduction. David J. Manson of Olympic National Park is the lead biological technician.

  4. State geothermal commercialization programs in ten Rocky Mountain states. Semi-annual progress report, July-December 1979

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Griffith, J.L.

    The activities and findings of the ten state teams participating in the Rocky Mountain Basin and Range Regional Hydrothermal Commercialization Program for the period are described. A summary of the state projects, compilation of project accomplishments, summary of findings, and a description of the major conclusions and recommendations are presented. Also included are chapters on the commercialization activities carried out by individual teams in each state: Arizona, Colorado, Idaho, Montana, Nevada, New-Mexico, North Dakota, South Dakota, Utah, and Wyoming. (MHR)

  5. Microwave and millimeter wave monolithic integrated circuits (MIMIC) program. MIMIC briefs: Summaries of phase 3 technology support programs

    NASA Astrophysics Data System (ADS)

    Kramer, Warner

    1993-01-01

    This publication contains technical and contractual summaries of the MIMIC program's Phase 3 technology support programs. Each project description includes a discussion of the objectives of the effort, the approach pursued, and recent progress. Also identified are the performing organization(s), principal investigator and/or other key personnel, contract number, program funding and duration, and program monitor/COTR. Concluding the document is a directory of the personnel associated with these projects, from whom more information may be requested.

  6. Hybridization and Polyploidization of Saccharomyces cerevisiae Strains by Transformation-Associated Cell Fusion

    PubMed Central

    Takagi, Atsuko; Harashima, Satoshi; Oshima, Yasuji

    1985-01-01

    Hybrid or polyploid clones of Saccharomyces cerevisiae produced by protoplast fusion were easily isolated by selecting transformants with the plasmid phenotype because the transformation was directly associated with cell fusion. When haploid cells were used as the original strain, the transformants were mostly diploids with a significant fraction of polyploids (triploids or tetraploids). Repeated transformation after curing the plasmid gave rise to clones with higher ploidy, but the frequency of cell fusion was severely reduced as ploidy increased. Images PMID:16346702

  7. Platform for immobilization and observation of subcellular processes

    DOEpatents

    McKnight, Timothy E.; Kalluri, Udaya C.; Melechko, Anatoli V.

    2014-08-26

    A method of immobilizing matter for imaging that includes providing an array of nanofibers and directing matter to the array of the nanofibers. The matter is immobilized when contacting at least three nanofibers of the array of nanofibers simultaneously. Adjacent nanofibers in the array of nanofibers may be separated by a pitch as great as 100 microns. The immobilized matter on the array of nanofibers may then be imaged. In some examples, the matter may be cell matter, such as protoplasts.

  8. Genetic Transformation of the Biocontrol Fungus Gliocladium virens to Benomyl Resistance

    PubMed Central

    Ossanna, Nina; Mischke, Sue

    1990-01-01

    Methodology was developed to isolate and regenerate protoplasts from the biocontrol fungus Gliocladium virens and to transform them to benomyl resistance with a Neurospora crassa β-tubulin gene. Southern blots demonstrated that multiple copies of the vector integrated into the chromosomal DNA of stable biotypes but not of abortive transformants. Analysis of nuclear condition in vegetative and asexual structures demonstrated that no structure of G. virens is dependably uninucleate and thus preferentially suitable for transformation. Images PMID:16348312

  9. Acoustics Discipline Overview

    NASA Technical Reports Server (NTRS)

    Envia, Edmane; Thomas, Russell

    2007-01-01

    As part of the Fundamental Aeronautics Program Annual Review, a summary of the progress made in 2007 in acoustics research under the Subsonic Fixed Wing project is given. The presentation describes highlights from in-house and external activities including partnerships and NRA-funded research with industry and academia. Brief progress reports from all acoustics Phase 1 NRAs are also included as are outlines of the planned activities for 2008 and all Phase 2 NRAs. N+1 and N+2 technology paths outlined for Subsonic Fixed Wing noise targets. NRA Round 1 progressing with focus on prediction method advancement. NRA Round 2 initiating work focused on N+2 technology, prediction methods, and validation. Excellent partnerships in progress supporting N+1 technology targets and providing key data sets.

  10. Sensing and capture of toxic and hazardous gases and vapors by metal–organic frameworks

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wang, Hao; Lustig, William P.; Li, Jing

    This review summaries recent progress in the luminescent detection and adsorptive removal of harmful gases and vapors by metal–organic frameworks, as well as the principles and strategies guiding the design of these materials.

  11. Project UCARE : Uniform Commuter Assistance Reporting and Evaluation for transportation demand management programs, [summary].

    DOT National Transportation Integrated Search

    2013-09-01

    The federal transportation reauthorization called : Moving Ahead for Progress in the 21st Century Act : (MAP-21) creates a program that addresses many : challenges facing the U.S. transportation system. : These challenges include improving safety, : ...

  12. Sensing and capture of toxic and hazardous gases and vapors by metal–organic frameworks

    DOE PAGES

    Wang, Hao; Lustig, William P.; Li, Jing

    2018-01-01

    This review summaries recent progress in the luminescent detection and adsorptive removal of harmful gases and vapors by metal–organic frameworks, as well as the principles and strategies guiding the design of these materials.

  13. Fuel Cell Buses in U.S. Transit Fleets: Current Status 2017

    DOT National Transportation Integrated Search

    2017-11-01

    This report, published annually, summarizes the progress of fuel cell electric bus (FCEB) development in the United States and discusses the achievements and challenges of introducing fuel cell propulsion in transit. The report provides a summary of ...

  14. Fuel Cell Buses in U.S. Transit Fleets: Current Status 2016

    DOT National Transportation Integrated Search

    2016-11-01

    This report, published annually, summarizes the progress of fuel cell electric bus (FCEB) development in the United States and discusses the achievements and challenges of introducing fuel cell propulsion in transit. The report provides a summary of ...

  15. SPod Progress Summary Slides

    EPA Science Inventory

    This presentation describes the draft “open source” design package for the SPod fenceline sensor. The SPod is a low cost, solar-powered system that combines wind field and air pollutant concentration measurements to detect emission plumes and help locate the source of emissions....

  16. Fuel Cell Buses in U.S. Transit Fleets : Current Status 2015

    DOT National Transportation Integrated Search

    2015-12-01

    This report, published annually, summarizes the progress of fuel cell electric bus (FCEB) development in the United States and discusses the achievements and challenges of introducing fuel cell propulsion in transit. The report provides a summary of ...

  17. Particle Physics at the University of Pittsburgh Summary Report for Proposal Period FY'09-11

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Boudreau, Joe; Dytman, Steven; Mueller, James

    Presented is the final summary report for grant DOE-FG02-91ER40646. The HEP group at the University consists of three tasks: B,D and L. Task B supports Pitt's CDF group at the energy frontier which includes Joe Boudreau and Paul Shepard. Work of the group includes Hao Song's thesis on the measurement of the B_c lifetime using exclusive J/psi+pion decays, and an update of the previous B_c semi-leptonic analyses under the supervision of Paul Shepard. Task D supports Pitt's neutrino group at the intensity frontier which includes PIs Dytman, Naples and Paolone. The group also includes postdoctoral research associate Danko, and thesismore » students Isvan (MINOS), Eberly (Minerva ), Ren (Minerva )and Hansen (T2K). This report summarizes their progress on ongoing experiments which are designed to make significant contributions to a detailed understanding of the neutrino mixing matrix. Task L supports Pitt's ATLAS group at the energy frontier and includes investigators Vladimir Savinov, James Mueller and Joe Boudreau. This group contributed both to hardware (calorimeter electronics, Savinov) and to software (Simulation, Detector Description, and Visualization: Boudreau and Mueller; MC generators: Savinov) and a summary of their progress is presented.« less

  18. Metals and Ceramics Division progress report for period ending June 30, 1984

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Brogden, I.

    1984-09-01

    This progress report covers the research and development activities of the Metals and Ceramics Division from January 1, 1983, through June 30, 1984. The format of the report follows the organizational structure of the division. Short summaries of technical work in progress in the various experimental groups are presented in six parts. Chapter 1 deals with the research and development activities of the Engineering Materials Section, Chapter 2 with the Processing Science and Technology Section, Chapter 3 with the Materials Science Section, Chapter 4 with Project Activities, Chapter 5 with Specialized Research Facilities and Equipment, and Chapter 6 with Miscellaneousmore » Activities.« less

  19. Solid State Division progress report for period ending March 31, 1997

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Green, P.H.; Hinton, L.W.

    1997-12-01

    This report covers research progress in the Solid State Division from April 1, 1995, through March 31, 1997. During this period, the division conducted a broad, interdisciplinary materials research program in support of Department of Energy science and technology missions. The report includes brief summaries of research activities in condensed matter theory, neutron scattering, synthesis and characterization of materials, ion beam and laser processing, and the structure of solids and surfaces. An addendum includes listings of division publications and professional activities.

  20. The Progress and Promise of Title V in the South. A Synopsis of Progress Reports on Title V Rural Development Programs in the Southern States. SRDC Series Publication No. 9.

    ERIC Educational Resources Information Center

    Southern Rural Development Center, State College, MS.

    More than 60 successful programs and projects developed specifically under Title V of the Rural Development Act of 1972 by 13 southern states and Puerto Rico are reported in this synopsis of Title V achievements in the southern region. A summary of benefits to people in 82 pilot counties of the rural South lists improved job opportunities, homes,…

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